The following changes since commit b2f7a038bb4c4fc5ce6b8486e8513dfd97665e2a: Merge remote-tracking branch 'remotes/rth/tags/pull-softfloat-20181104' into staging (2018-11-05 10:32:49 +0000) are available in the Git repository at: git://repo.or.cz/qemu/kevin.git tags/for-upstream for you to fetch changes up to 1240ac558d348f6c7a5752b1a57c1da58e4efe3e: include: Add a comment to explain the origin of sizes' lookup table (2018-11-05 15:29:59 +0100) ---------------------------------------------------------------- Block layer patches: - auto-read-only option to fix commit job when used with -blockdev - Fix help text related qemu-iotests failure (by improving the help text and updating the reference output) - quorum: Add missing checks when adding/removing child nodes - Don't take address of fields in packed structs - vvfat: Fix crash when reporting error about too many files in directory ---------------------------------------------------------------- Alberto Garcia (7): block: replace "discard" literal with BDRV_OPT_DISCARD macro qcow2: Get the request alignment for encrypted images from QCryptoBlock quorum: Remove quorum_err() quorum: Return an error if the blkverify mode has invalid settings iotest: Test the blkverify mode of the Quorum driver quorum: Forbid adding children in blkverify mode iotest: Test x-blockdev-change on a Quorum Cleber Rosa (1): iotests: make 083 specific to raw Daniel P. Berrangé (1): crypto: initialize sector size even when opening with no IO flag Kevin Wolf (12): vpc: Don't leak opts in vpc_open() block: Update flags in bdrv_set_read_only() block: Add auto-read-only option rbd: Close image in qemu_rbd_open() error path block: Require auto-read-only for existing fallbacks nbd: Support auto-read-only option file-posix: Support auto-read-only option curl: Support auto-read-only option gluster: Support auto-read-only option iscsi: Support auto-read-only option block: Make auto-read-only=on default for -drive qemu-iotests: Test auto-read-only with -drive and -blockdev Leonid Bloch (2): vdi: Use a literal number of bytes for DEFAULT_CLUSTER_SIZE include: Add a comment to explain the origin of sizes' lookup table Li Qiang (1): block: change some function return type to bool Max Reitz (5): option: Make option help nicer to read chardev: Indent list of chardevs qdev-monitor: Make device options help nicer object: Make option help nicer to read fw_cfg: Drop newline in @file description Peter Maydell (5): block/qcow2: Don't take address of fields in packed structs block/qcow: Don't take address of fields in packed structs block/qcow2-bitmap: Don't take address of fields in packed structs block/vhdx: Don't take address of fields in packed structs block/vdi: Don't take address of fields in packed structs Stefan Weil (1): qemu-io-cmds: Fix two format strings Thomas Huth (1): block/vvfat: Fix crash when reporting error about too many files in directory qapi/block-core.json | 7 + block/vhdx.h | 12 +- include/block/block.h | 5 +- include/qemu/option.h | 2 +- include/qemu/units.h | 18 + include/sysemu/block-backend.h | 6 +- block.c | 60 ++- block/block-backend.c | 8 +- block/bochs.c | 17 +- block/cloop.c | 16 +- block/curl.c | 8 +- block/dmg.c | 16 +- block/file-posix.c | 19 +- block/gluster.c | 12 +- block/iscsi.c | 8 +- block/nbd-client.c | 10 +- block/qcow.c | 18 +- block/qcow2-bitmap.c | 24 +- block/qcow2.c | 66 +-- block/quorum.c | 45 +- block/rbd.c | 14 +- block/vdi.c | 68 +-- block/vhdx-endian.c | 118 ++--- block/vhdx-log.c | 4 +- block/vhdx.c | 18 +- block/vpc.c | 2 + block/vvfat.c | 15 +- blockdev.c | 3 +- chardev/char.c | 2 +- crypto/block-qcow.c | 2 + qdev-monitor.c | 13 +- qemu-img.c | 4 +- qemu-io-cmds.c | 4 +- util/qemu-option.c | 32 +- vl.c | 15 +- tests/qemu-iotests/081 | 116 +++++ tests/qemu-iotests/081.out | 70 +++ tests/qemu-iotests/082.out | 956 ++++++++++++++++++++--------------------- tests/qemu-iotests/083 | 2 +- tests/qemu-iotests/232 | 147 +++++++ tests/qemu-iotests/232.out | 59 +++ tests/qemu-iotests/group | 1 + 42 files changed, 1266 insertions(+), 776 deletions(-) create mode 100755 tests/qemu-iotests/232 create mode 100644 tests/qemu-iotests/232.out From: Thomas Huth <thuth@redhat.com> When using the vvfat driver with a directory that contains too many files, QEMU currently crashes. This can be triggered like this for example: mkdir /tmp/vvfattest cd /tmp/vvfattest for ((x=0;x<=513;x++)); do mkdir $x; done qemu-system-x86_64 -drive \ file.driver=vvfat,file.dir=.,read-only=on,media=cdrom Seems like read_directory() is changing the mapping->path variable. Make sure we use the right pointer instead. Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vvfat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/vvfat.c b/block/vvfat.c index XXXXXXX..XXXXXXX 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -XXX,XX +XXX,XX @@ static int init_directories(BDRVVVFATState* s, mapping = array_get(&(s->mapping), i); if (mapping->mode & MODE_DIRECTORY) { + char *path = mapping->path; mapping->begin = cluster; if(read_directory(s, i)) { - error_setg(errp, "Could not read directory %s", - mapping->path); + error_setg(errp, "Could not read directory %s", path); return -1; } mapping = array_get(&(s->mapping), i); -- 2.19.1 From: Alberto Garcia <berto@igalia.com> Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ QemuOptsList bdrv_runtime_opts = { .help = "try to optimize zero writes (off, on, unmap)", }, { - .name = "discard", + .name = BDRV_OPT_DISCARD, .type = QEMU_OPT_STRING, .help = "discard operation (ignore/off, unmap/on)", }, @@ -XXX,XX +XXX,XX @@ static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, } } - discard = qemu_opt_get(opts, "discard"); + discard = qemu_opt_get(opts, BDRV_OPT_DISCARD); if (discard != NULL) { if (bdrv_parse_discard_flags(discard, &bs->open_flags) != 0) { error_setg(errp, "Invalid discard option"); @@ -XXX,XX +XXX,XX @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, update_flags_from_options(&reopen_state->flags, opts); - discard = qemu_opt_get_del(opts, "discard"); + discard = qemu_opt_get_del(opts, BDRV_OPT_DISCARD); if (discard != NULL) { if (bdrv_parse_discard_flags(discard, &reopen_state->flags) != 0) { error_setg(errp, "Invalid discard option"); -- 2.19.1 From: Stefan Weil <sw@weilnetz.de> Use %zu instead of %zd for unsigned numbers. This fixes two error messages from the LSTM static code analyzer: This argument should be of type 'ssize_t' but is of type 'unsigned long' Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- qemu-io-cmds.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c index XXXXXXX..XXXXXXX 100644 --- a/qemu-io-cmds.c +++ b/qemu-io-cmds.c @@ -XXX,XX +XXX,XX @@ static int readv_f(BlockBackend *blk, int argc, char **argv) memset(cmp_buf, pattern, qiov.size); if (memcmp(buf, cmp_buf, qiov.size)) { printf("Pattern verification failed at offset %" - PRId64 ", %zd bytes\n", offset, qiov.size); + PRId64 ", %zu bytes\n", offset, qiov.size); ret = -EINVAL; } g_free(cmp_buf); @@ -XXX,XX +XXX,XX @@ static void aio_read_done(void *opaque, int ret) memset(cmp_buf, ctx->pattern, ctx->qiov.size); if (memcmp(ctx->buf, cmp_buf, ctx->qiov.size)) { printf("Pattern verification failed at offset %" - PRId64 ", %zd bytes\n", ctx->offset, ctx->qiov.size); + PRId64 ", %zu bytes\n", ctx->offset, ctx->qiov.size); } g_free(cmp_buf); } -- 2.19.1 From: Peter Maydell <peter.maydell@linaro.org> Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. This patch was produced with the following spatch script (and hand-editing to fold a few resulting overlength lines): @@ expression E; @@ -be16_to_cpus(&E); +E = be16_to_cpu(E); @@ expression E; @@ -be32_to_cpus(&E); +E = be32_to_cpu(E); @@ expression E; @@ -be64_to_cpus(&E); +E = be64_to_cpu(E); @@ expression E; @@ -cpu_to_be16s(&E); +E = cpu_to_be16(E); @@ expression E; @@ -cpu_to_be32s(&E); +E = cpu_to_be32(E); @@ expression E; @@ -cpu_to_be64s(&E); +E = cpu_to_be64(E); Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Tested-by: John Snow <jsnow@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2.c | 64 +++++++++++++++++++++++++++------------------------ 1 file changed, 34 insertions(+), 30 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -XXX,XX +XXX,XX @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, "pread fail from offset %" PRIu64, offset); return 1; } - be32_to_cpus(&ext.magic); - be32_to_cpus(&ext.len); + ext.magic = be32_to_cpu(ext.magic); + ext.len = be32_to_cpu(ext.len); offset += sizeof(ext); #ifdef DEBUG_EXT printf("ext.magic = 0x%x\n", ext.magic); @@ -XXX,XX +XXX,XX @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, "Unable to read CRYPTO header extension"); return ret; } - be64_to_cpus(&s->crypto_header.offset); - be64_to_cpus(&s->crypto_header.length); + s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset); + s->crypto_header.length = be64_to_cpu(s->crypto_header.length); if ((s->crypto_header.offset % s->cluster_size) != 0) { error_setg(errp, "Encryption header offset '%" PRIu64 "' is " @@ -XXX,XX +XXX,XX @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, return -EINVAL; } - be32_to_cpus(&bitmaps_ext.nb_bitmaps); - be64_to_cpus(&bitmaps_ext.bitmap_directory_size); - be64_to_cpus(&bitmaps_ext.bitmap_directory_offset); + bitmaps_ext.nb_bitmaps = be32_to_cpu(bitmaps_ext.nb_bitmaps); + bitmaps_ext.bitmap_directory_size = + be64_to_cpu(bitmaps_ext.bitmap_directory_size); + bitmaps_ext.bitmap_directory_offset = + be64_to_cpu(bitmaps_ext.bitmap_directory_offset); if (bitmaps_ext.nb_bitmaps > QCOW2_MAX_BITMAPS) { error_setg(errp, @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, error_setg_errno(errp, -ret, "Could not read qcow2 header"); goto fail; } - be32_to_cpus(&header.magic); - be32_to_cpus(&header.version); - be64_to_cpus(&header.backing_file_offset); - be32_to_cpus(&header.backing_file_size); - be64_to_cpus(&header.size); - be32_to_cpus(&header.cluster_bits); - be32_to_cpus(&header.crypt_method); - be64_to_cpus(&header.l1_table_offset); - be32_to_cpus(&header.l1_size); - be64_to_cpus(&header.refcount_table_offset); - be32_to_cpus(&header.refcount_table_clusters); - be64_to_cpus(&header.snapshots_offset); - be32_to_cpus(&header.nb_snapshots); + header.magic = be32_to_cpu(header.magic); + header.version = be32_to_cpu(header.version); + header.backing_file_offset = be64_to_cpu(header.backing_file_offset); + header.backing_file_size = be32_to_cpu(header.backing_file_size); + header.size = be64_to_cpu(header.size); + header.cluster_bits = be32_to_cpu(header.cluster_bits); + header.crypt_method = be32_to_cpu(header.crypt_method); + header.l1_table_offset = be64_to_cpu(header.l1_table_offset); + header.l1_size = be32_to_cpu(header.l1_size); + header.refcount_table_offset = be64_to_cpu(header.refcount_table_offset); + header.refcount_table_clusters = + be32_to_cpu(header.refcount_table_clusters); + header.snapshots_offset = be64_to_cpu(header.snapshots_offset); + header.nb_snapshots = be32_to_cpu(header.nb_snapshots); if (header.magic != QCOW_MAGIC) { error_setg(errp, "Image is not in qcow2 format"); @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, header.refcount_order = 4; header.header_length = 72; } else { - be64_to_cpus(&header.incompatible_features); - be64_to_cpus(&header.compatible_features); - be64_to_cpus(&header.autoclear_features); - be32_to_cpus(&header.refcount_order); - be32_to_cpus(&header.header_length); + header.incompatible_features = + be64_to_cpu(header.incompatible_features); + header.compatible_features = be64_to_cpu(header.compatible_features); + header.autoclear_features = be64_to_cpu(header.autoclear_features); + header.refcount_order = be32_to_cpu(header.refcount_order); + header.header_length = be32_to_cpu(header.header_length); if (header.header_length < 104) { error_setg(errp, "qcow2 header too short"); @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, goto fail; } for(i = 0;i < s->l1_size; i++) { - be64_to_cpus(&s->l1_table[i]); + s->l1_table[i] = be64_to_cpu(s->l1_table[i]); } } @@ -XXX,XX +XXX,XX @@ int qcow2_update_header(BlockDriverState *bs) /* Full disk encryption header pointer extension */ if (s->crypto_header.offset != 0) { - cpu_to_be64s(&s->crypto_header.offset); - cpu_to_be64s(&s->crypto_header.length); + s->crypto_header.offset = cpu_to_be64(s->crypto_header.offset); + s->crypto_header.length = cpu_to_be64(s->crypto_header.length); ret = header_ext_add(buf, QCOW2_EXT_MAGIC_CRYPTO_HEADER, &s->crypto_header, sizeof(s->crypto_header), buflen); - be64_to_cpus(&s->crypto_header.offset); - be64_to_cpus(&s->crypto_header.length); + s->crypto_header.offset = be64_to_cpu(s->crypto_header.offset); + s->crypto_header.length = be64_to_cpu(s->crypto_header.length); if (ret < 0) { goto fail; } -- 2.19.1 From: Peter Maydell <peter.maydell@linaro.org> Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. This patch was produced with the following spatch script: @@ expression E; @@ -be16_to_cpus(&E); +E = be16_to_cpu(E); @@ expression E; @@ -be32_to_cpus(&E); +E = be32_to_cpu(E); @@ expression E; @@ -be64_to_cpus(&E); +E = be64_to_cpu(E); @@ expression E; @@ -cpu_to_be16s(&E); +E = cpu_to_be16(E); @@ expression E; @@ -cpu_to_be32s(&E); +E = cpu_to_be32(E); @@ expression E; @@ -cpu_to_be64s(&E); +E = cpu_to_be64(E); Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Tested-by: John Snow <jsnow@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/block/qcow.c b/block/qcow.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -XXX,XX +XXX,XX @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, if (ret < 0) { goto fail; } - be32_to_cpus(&header.magic); - be32_to_cpus(&header.version); - be64_to_cpus(&header.backing_file_offset); - be32_to_cpus(&header.backing_file_size); - be32_to_cpus(&header.mtime); - be64_to_cpus(&header.size); - be32_to_cpus(&header.crypt_method); - be64_to_cpus(&header.l1_table_offset); + header.magic = be32_to_cpu(header.magic); + header.version = be32_to_cpu(header.version); + header.backing_file_offset = be64_to_cpu(header.backing_file_offset); + header.backing_file_size = be32_to_cpu(header.backing_file_size); + header.mtime = be32_to_cpu(header.mtime); + header.size = be64_to_cpu(header.size); + header.crypt_method = be32_to_cpu(header.crypt_method); + header.l1_table_offset = be64_to_cpu(header.l1_table_offset); if (header.magic != QCOW_MAGIC) { error_setg(errp, "Image not in qcow format"); @@ -XXX,XX +XXX,XX @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags, } for(i = 0;i < s->l1_size; i++) { - be64_to_cpus(&s->l1_table[i]); + s->l1_table[i] = be64_to_cpu(s->l1_table[i]); } /* alloc L2 cache (max. 64k * 16 * 8 = 8 MB) */ -- 2.19.1 From: Peter Maydell <peter.maydell@linaro.org> Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. This patch was produced with the following spatch script: @@ expression E; @@ -be16_to_cpus(&E); +E = be16_to_cpu(E); @@ expression E; @@ -be32_to_cpus(&E); +E = be32_to_cpu(E); @@ expression E; @@ -be64_to_cpus(&E); +E = be64_to_cpu(E); @@ expression E; @@ -cpu_to_be16s(&E); +E = cpu_to_be16(E); @@ expression E; @@ -cpu_to_be32s(&E); +E = cpu_to_be32(E); @@ expression E; @@ -cpu_to_be64s(&E); +E = cpu_to_be64(E); Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Tested-by: John Snow <jsnow@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2-bitmap.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -XXX,XX +XXX,XX @@ static inline void bitmap_table_to_be(uint64_t *bitmap_table, size_t size) size_t i; for (i = 0; i < size; ++i) { - cpu_to_be64s(&bitmap_table[i]); + bitmap_table[i] = cpu_to_be64(bitmap_table[i]); } } @@ -XXX,XX +XXX,XX @@ static int bitmap_table_load(BlockDriverState *bs, Qcow2BitmapTable *tb, } for (i = 0; i < tb->size; ++i) { - be64_to_cpus(&table[i]); + table[i] = be64_to_cpu(table[i]); ret = check_table_entry(table[i], s->cluster_size); if (ret < 0) { goto fail; @@ -XXX,XX +XXX,XX @@ fail: static inline void bitmap_dir_entry_to_cpu(Qcow2BitmapDirEntry *entry) { - be64_to_cpus(&entry->bitmap_table_offset); - be32_to_cpus(&entry->bitmap_table_size); - be32_to_cpus(&entry->flags); - be16_to_cpus(&entry->name_size); - be32_to_cpus(&entry->extra_data_size); + entry->bitmap_table_offset = be64_to_cpu(entry->bitmap_table_offset); + entry->bitmap_table_size = be32_to_cpu(entry->bitmap_table_size); + entry->flags = be32_to_cpu(entry->flags); + entry->name_size = be16_to_cpu(entry->name_size); + entry->extra_data_size = be32_to_cpu(entry->extra_data_size); } static inline void bitmap_dir_entry_to_be(Qcow2BitmapDirEntry *entry) { - cpu_to_be64s(&entry->bitmap_table_offset); - cpu_to_be32s(&entry->bitmap_table_size); - cpu_to_be32s(&entry->flags); - cpu_to_be16s(&entry->name_size); - cpu_to_be32s(&entry->extra_data_size); + entry->bitmap_table_offset = cpu_to_be64(entry->bitmap_table_offset); + entry->bitmap_table_size = cpu_to_be32(entry->bitmap_table_size); + entry->flags = cpu_to_be32(entry->flags); + entry->name_size = cpu_to_be16(entry->name_size); + entry->extra_data_size = cpu_to_be32(entry->extra_data_size); } static inline int calc_dir_entry_size(size_t name_size, size_t extra_data_size) -- 2.19.1 From: Daniel P. Berrangé <berrange@redhat.com> The qcow2 block driver expects to see a valid sector size even when it has opened the crypto layer with QCRYPTO_BLOCK_OPEN_NO_IO. Signed-off-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- crypto/block-qcow.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/crypto/block-qcow.c b/crypto/block-qcow.c index XXXXXXX..XXXXXXX 100644 --- a/crypto/block-qcow.c +++ b/crypto/block-qcow.c @@ -XXX,XX +XXX,XX @@ qcrypto_block_qcow_open(QCryptoBlock *block, Error **errp) { if (flags & QCRYPTO_BLOCK_OPEN_NO_IO) { + block->sector_size = QCRYPTO_BLOCK_QCOW_SECTOR_SIZE; + block->payload_offset = 0; return 0; } else { if (!options->u.qcow.key_secret) { -- 2.19.1 From: Alberto Garcia <berto@igalia.com> This doesn't have any practical effect at the moment because the values of BDRV_SECTOR_SIZE, QCRYPTO_BLOCK_LUKS_SECTOR_SIZE and QCRYPTO_BLOCK_QCOW_SECTOR_SIZE are all the same (512 bytes), but future encryption methods could have different requirements. Signed-off-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/qcow2.c b/block/qcow2.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -XXX,XX +XXX,XX @@ static void qcow2_refresh_limits(BlockDriverState *bs, Error **errp) if (bs->encrypted) { /* Encryption works on a sector granularity */ - bs->bl.request_alignment = BDRV_SECTOR_SIZE; + bs->bl.request_alignment = qcrypto_block_get_sector_size(s->crypto); } bs->bl.pwrite_zeroes_alignment = s->cluster_size; bs->bl.pdiscard_alignment = s->cluster_size; -- 2.19.1 From: Li Qiang <liq3ea@163.com> Signed-off-by: Li Qiang <liq3ea@163.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/sysemu/block-backend.h | 6 +++--- block/block-backend.c | 8 ++++---- 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/include/sysemu/block-backend.h b/include/sysemu/block-backend.h index XXXXXXX..XXXXXXX 100644 --- a/include/sysemu/block-backend.h +++ b/include/sysemu/block-backend.h @@ -XXX,XX +XXX,XX @@ BlockErrorAction blk_get_error_action(BlockBackend *blk, bool is_read, int error); void blk_error_action(BlockBackend *blk, BlockErrorAction action, bool is_read, int error); -int blk_is_read_only(BlockBackend *blk); -int blk_is_sg(BlockBackend *blk); -int blk_enable_write_cache(BlockBackend *blk); +bool blk_is_read_only(BlockBackend *blk); +bool blk_is_sg(BlockBackend *blk); +bool blk_enable_write_cache(BlockBackend *blk); void blk_set_enable_write_cache(BlockBackend *blk, bool wce); void blk_invalidate_cache(BlockBackend *blk, Error **errp); bool blk_is_inserted(BlockBackend *blk); diff --git a/block/block-backend.c b/block/block-backend.c index XXXXXXX..XXXXXXX 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -XXX,XX +XXX,XX @@ void blk_error_action(BlockBackend *blk, BlockErrorAction action, } } -int blk_is_read_only(BlockBackend *blk) +bool blk_is_read_only(BlockBackend *blk) { BlockDriverState *bs = blk_bs(blk); @@ -XXX,XX +XXX,XX @@ int blk_is_read_only(BlockBackend *blk) } } -int blk_is_sg(BlockBackend *blk) +bool blk_is_sg(BlockBackend *blk) { BlockDriverState *bs = blk_bs(blk); if (!bs) { - return 0; + return false; } return bdrv_is_sg(bs); } -int blk_enable_write_cache(BlockBackend *blk) +bool blk_enable_write_cache(BlockBackend *blk) { return blk->enable_write_cache; } -- 2.19.1 From: Cleber Rosa <crosa@redhat.com> While testing the Python 3 changes which touch the 083 test, I noticed that it would fail with qcow2. Expanding the testing, I noticed it had nothing to do with the Python 3 changes, and in fact, it would not pass on anything but raw: raw: pass bochs: not generic cloop: not generic parallels: fail qcow: fail qcow2: fail qed: fail vdi: fail vhdx: fail vmdk: fail vpc: fail luks: fail The errors are a mixture I/O and "image not in xxx format", such as: === Check disconnect before data === Unexpected end-of-file before all bytes were read -read failed: Input/output error +can't open device nbd+tcp://127.0.0.1:PORT/foo: Could not open 'nbd://127.0.0.1:PORT/foo': Input/output error === Check disconnect after data === -read 512/512 bytes at offset 0 -512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +can't open device nbd+tcp://127.0.0.1:PORT/foo: Image not in qcow format I'm not aware if there's a quick fix, so, for the time being, it looks like the honest approach is to make the test known to work on raw only. Signed-off-by: Cleber Rosa <crosa@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/083 | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tests/qemu-iotests/083 b/tests/qemu-iotests/083 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/083 +++ b/tests/qemu-iotests/083 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 . ./common.rc . ./common.filter -_supported_fmt generic +_supported_fmt raw _supported_proto nbd _supported_os Linux -- 2.19.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> --- block/vpc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/vpc.c b/block/vpc.c index XXXXXXX..XXXXXXX 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -XXX,XX +XXX,XX @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags, } qemu_co_mutex_init(&s->lock); + qemu_opts_del(opts); return 0; fail: + qemu_opts_del(opts); qemu_vfree(s->pagetable); #ifdef CACHE g_free(s->pageentry_u8); -- 2.19.1 From: Peter Maydell <peter.maydell@linaro.org> Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. Patch produced with scripts/coccinelle/inplace-byteswaps.cocci. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vhdx.h | 12 ++--- block/vhdx-endian.c | 118 ++++++++++++++++++++++---------------------- block/vhdx-log.c | 4 +- block/vhdx.c | 18 +++---- 4 files changed, 76 insertions(+), 76 deletions(-) diff --git a/block/vhdx.h b/block/vhdx.h index XXXXXXX..XXXXXXX 100644 --- a/block/vhdx.h +++ b/block/vhdx.h @@ -XXX,XX +XXX,XX @@ int vhdx_log_write_and_flush(BlockDriverState *bs, BDRVVHDXState *s, static inline void leguid_to_cpus(MSGUID *guid) { - le32_to_cpus(&guid->data1); - le16_to_cpus(&guid->data2); - le16_to_cpus(&guid->data3); + guid->data1 = le32_to_cpu(guid->data1); + guid->data2 = le16_to_cpu(guid->data2); + guid->data3 = le16_to_cpu(guid->data3); } static inline void cpu_to_leguids(MSGUID *guid) { - cpu_to_le32s(&guid->data1); - cpu_to_le16s(&guid->data2); - cpu_to_le16s(&guid->data3); + guid->data1 = cpu_to_le32(guid->data1); + guid->data2 = cpu_to_le16(guid->data2); + guid->data3 = cpu_to_le16(guid->data3); } void vhdx_header_le_import(VHDXHeader *h); diff --git a/block/vhdx-endian.c b/block/vhdx-endian.c index XXXXXXX..XXXXXXX 100644 --- a/block/vhdx-endian.c +++ b/block/vhdx-endian.c @@ -XXX,XX +XXX,XX @@ void vhdx_header_le_import(VHDXHeader *h) { assert(h != NULL); - le32_to_cpus(&h->signature); - le32_to_cpus(&h->checksum); - le64_to_cpus(&h->sequence_number); + h->signature = le32_to_cpu(h->signature); + h->checksum = le32_to_cpu(h->checksum); + h->sequence_number = le64_to_cpu(h->sequence_number); leguid_to_cpus(&h->file_write_guid); leguid_to_cpus(&h->data_write_guid); leguid_to_cpus(&h->log_guid); - le16_to_cpus(&h->log_version); - le16_to_cpus(&h->version); - le32_to_cpus(&h->log_length); - le64_to_cpus(&h->log_offset); + h->log_version = le16_to_cpu(h->log_version); + h->version = le16_to_cpu(h->version); + h->log_length = le32_to_cpu(h->log_length); + h->log_offset = le64_to_cpu(h->log_offset); } void vhdx_header_le_export(VHDXHeader *orig_h, VHDXHeader *new_h) @@ -XXX,XX +XXX,XX @@ void vhdx_log_desc_le_import(VHDXLogDescriptor *d) { assert(d != NULL); - le32_to_cpus(&d->signature); - le64_to_cpus(&d->file_offset); - le64_to_cpus(&d->sequence_number); + d->signature = le32_to_cpu(d->signature); + d->file_offset = le64_to_cpu(d->file_offset); + d->sequence_number = le64_to_cpu(d->sequence_number); } void vhdx_log_desc_le_export(VHDXLogDescriptor *d) { assert(d != NULL); - cpu_to_le32s(&d->signature); - cpu_to_le32s(&d->trailing_bytes); - cpu_to_le64s(&d->leading_bytes); - cpu_to_le64s(&d->file_offset); - cpu_to_le64s(&d->sequence_number); + d->signature = cpu_to_le32(d->signature); + d->trailing_bytes = cpu_to_le32(d->trailing_bytes); + d->leading_bytes = cpu_to_le64(d->leading_bytes); + d->file_offset = cpu_to_le64(d->file_offset); + d->sequence_number = cpu_to_le64(d->sequence_number); } void vhdx_log_data_le_import(VHDXLogDataSector *d) { assert(d != NULL); - le32_to_cpus(&d->data_signature); - le32_to_cpus(&d->sequence_high); - le32_to_cpus(&d->sequence_low); + d->data_signature = le32_to_cpu(d->data_signature); + d->sequence_high = le32_to_cpu(d->sequence_high); + d->sequence_low = le32_to_cpu(d->sequence_low); } void vhdx_log_data_le_export(VHDXLogDataSector *d) { assert(d != NULL); - cpu_to_le32s(&d->data_signature); - cpu_to_le32s(&d->sequence_high); - cpu_to_le32s(&d->sequence_low); + d->data_signature = cpu_to_le32(d->data_signature); + d->sequence_high = cpu_to_le32(d->sequence_high); + d->sequence_low = cpu_to_le32(d->sequence_low); } void vhdx_log_entry_hdr_le_import(VHDXLogEntryHeader *hdr) { assert(hdr != NULL); - le32_to_cpus(&hdr->signature); - le32_to_cpus(&hdr->checksum); - le32_to_cpus(&hdr->entry_length); - le32_to_cpus(&hdr->tail); - le64_to_cpus(&hdr->sequence_number); - le32_to_cpus(&hdr->descriptor_count); + hdr->signature = le32_to_cpu(hdr->signature); + hdr->checksum = le32_to_cpu(hdr->checksum); + hdr->entry_length = le32_to_cpu(hdr->entry_length); + hdr->tail = le32_to_cpu(hdr->tail); + hdr->sequence_number = le64_to_cpu(hdr->sequence_number); + hdr->descriptor_count = le32_to_cpu(hdr->descriptor_count); leguid_to_cpus(&hdr->log_guid); - le64_to_cpus(&hdr->flushed_file_offset); - le64_to_cpus(&hdr->last_file_offset); + hdr->flushed_file_offset = le64_to_cpu(hdr->flushed_file_offset); + hdr->last_file_offset = le64_to_cpu(hdr->last_file_offset); } void vhdx_log_entry_hdr_le_export(VHDXLogEntryHeader *hdr) { assert(hdr != NULL); - cpu_to_le32s(&hdr->signature); - cpu_to_le32s(&hdr->checksum); - cpu_to_le32s(&hdr->entry_length); - cpu_to_le32s(&hdr->tail); - cpu_to_le64s(&hdr->sequence_number); - cpu_to_le32s(&hdr->descriptor_count); + hdr->signature = cpu_to_le32(hdr->signature); + hdr->checksum = cpu_to_le32(hdr->checksum); + hdr->entry_length = cpu_to_le32(hdr->entry_length); + hdr->tail = cpu_to_le32(hdr->tail); + hdr->sequence_number = cpu_to_le64(hdr->sequence_number); + hdr->descriptor_count = cpu_to_le32(hdr->descriptor_count); cpu_to_leguids(&hdr->log_guid); - cpu_to_le64s(&hdr->flushed_file_offset); - cpu_to_le64s(&hdr->last_file_offset); + hdr->flushed_file_offset = cpu_to_le64(hdr->flushed_file_offset); + hdr->last_file_offset = cpu_to_le64(hdr->last_file_offset); } @@ -XXX,XX +XXX,XX @@ void vhdx_region_header_le_import(VHDXRegionTableHeader *hdr) { assert(hdr != NULL); - le32_to_cpus(&hdr->signature); - le32_to_cpus(&hdr->checksum); - le32_to_cpus(&hdr->entry_count); + hdr->signature = le32_to_cpu(hdr->signature); + hdr->checksum = le32_to_cpu(hdr->checksum); + hdr->entry_count = le32_to_cpu(hdr->entry_count); } void vhdx_region_header_le_export(VHDXRegionTableHeader *hdr) { assert(hdr != NULL); - cpu_to_le32s(&hdr->signature); - cpu_to_le32s(&hdr->checksum); - cpu_to_le32s(&hdr->entry_count); + hdr->signature = cpu_to_le32(hdr->signature); + hdr->checksum = cpu_to_le32(hdr->checksum); + hdr->entry_count = cpu_to_le32(hdr->entry_count); } void vhdx_region_entry_le_import(VHDXRegionTableEntry *e) @@ -XXX,XX +XXX,XX @@ void vhdx_region_entry_le_import(VHDXRegionTableEntry *e) assert(e != NULL); leguid_to_cpus(&e->guid); - le64_to_cpus(&e->file_offset); - le32_to_cpus(&e->length); - le32_to_cpus(&e->data_bits); + e->file_offset = le64_to_cpu(e->file_offset); + e->length = le32_to_cpu(e->length); + e->data_bits = le32_to_cpu(e->data_bits); } void vhdx_region_entry_le_export(VHDXRegionTableEntry *e) @@ -XXX,XX +XXX,XX @@ void vhdx_region_entry_le_export(VHDXRegionTableEntry *e) assert(e != NULL); cpu_to_leguids(&e->guid); - cpu_to_le64s(&e->file_offset); - cpu_to_le32s(&e->length); - cpu_to_le32s(&e->data_bits); + e->file_offset = cpu_to_le64(e->file_offset); + e->length = cpu_to_le32(e->length); + e->data_bits = cpu_to_le32(e->data_bits); } @@ -XXX,XX +XXX,XX @@ void vhdx_metadata_header_le_import(VHDXMetadataTableHeader *hdr) { assert(hdr != NULL); - le64_to_cpus(&hdr->signature); - le16_to_cpus(&hdr->entry_count); + hdr->signature = le64_to_cpu(hdr->signature); + hdr->entry_count = le16_to_cpu(hdr->entry_count); } void vhdx_metadata_header_le_export(VHDXMetadataTableHeader *hdr) { assert(hdr != NULL); - cpu_to_le64s(&hdr->signature); - cpu_to_le16s(&hdr->entry_count); + hdr->signature = cpu_to_le64(hdr->signature); + hdr->entry_count = cpu_to_le16(hdr->entry_count); } void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e) @@ -XXX,XX +XXX,XX @@ void vhdx_metadata_entry_le_import(VHDXMetadataTableEntry *e) assert(e != NULL); leguid_to_cpus(&e->item_id); - le32_to_cpus(&e->offset); - le32_to_cpus(&e->length); - le32_to_cpus(&e->data_bits); + e->offset = le32_to_cpu(e->offset); + e->length = le32_to_cpu(e->length); + e->data_bits = le32_to_cpu(e->data_bits); } void vhdx_metadata_entry_le_export(VHDXMetadataTableEntry *e) { assert(e != NULL); cpu_to_leguids(&e->item_id); - cpu_to_le32s(&e->offset); - cpu_to_le32s(&e->length); - cpu_to_le32s(&e->data_bits); + e->offset = cpu_to_le32(e->offset); + e->length = cpu_to_le32(e->length); + e->data_bits = cpu_to_le32(e->data_bits); } diff --git a/block/vhdx-log.c b/block/vhdx-log.c index XXXXXXX..XXXXXXX 100644 --- a/block/vhdx-log.c +++ b/block/vhdx-log.c @@ -XXX,XX +XXX,XX @@ static void vhdx_log_raw_to_le_sector(VHDXLogDescriptor *desc, /* 8 + 4084 + 4 = 4096, 1 log sector */ memcpy(&desc->leading_bytes, data, 8); data += 8; - cpu_to_le64s(&desc->leading_bytes); + desc->leading_bytes = cpu_to_le64(desc->leading_bytes); memcpy(sector->data, data, 4084); data += 4084; memcpy(&desc->trailing_bytes, data, 4); - cpu_to_le32s(&desc->trailing_bytes); + desc->trailing_bytes = cpu_to_le32(desc->trailing_bytes); data += 4; sector->sequence_high = (uint32_t) (seq >> 32); diff --git a/block/vhdx.c b/block/vhdx.c index XXXXXXX..XXXXXXX 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -XXX,XX +XXX,XX @@ uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) memset(buf + crc_offset, 0, sizeof(crc)); crc = crc32c(0xffffffff, buf, size); - cpu_to_le32s(&crc); + crc = cpu_to_le32(crc); memcpy(buf + crc_offset, &crc, sizeof(crc)); return crc; @@ -XXX,XX +XXX,XX @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) goto exit; } - le32_to_cpus(&s->params.block_size); - le32_to_cpus(&s->params.data_bits); + s->params.block_size = le32_to_cpu(s->params.block_size); + s->params.data_bits = le32_to_cpu(s->params.data_bits); /* We now have the file parameters, so we can tell if this is a @@ -XXX,XX +XXX,XX @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) goto exit; } - le64_to_cpus(&s->virtual_disk_size); - le32_to_cpus(&s->logical_sector_size); - le32_to_cpus(&s->physical_sector_size); + s->virtual_disk_size = le64_to_cpu(s->virtual_disk_size); + s->logical_sector_size = le32_to_cpu(s->logical_sector_size); + s->physical_sector_size = le32_to_cpu(s->physical_sector_size); if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || s->params.block_size > VHDX_BLOCK_SIZE_MAX) { @@ -XXX,XX +XXX,XX @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, /* endian convert, and verify populated BAT field file offsets against * region table and log entries */ for (i = 0; i < s->bat_entries; i++) { - le64_to_cpus(&s->bat[i]); + s->bat[i] = le64_to_cpu(s->bat[i]); if (payblocks--) { /* payload bat entries */ if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == @@ -XXX,XX +XXX,XX @@ static int vhdx_create_new_metadata(BlockBackend *blk, mt_file_params->block_size = cpu_to_le32(block_size); if (type == VHDX_TYPE_FIXED) { mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; - cpu_to_le32s(&mt_file_params->data_bits); + mt_file_params->data_bits = cpu_to_le32(mt_file_params->data_bits); } vhdx_guid_generate(&mt_page83->page_83_data); @@ -XXX,XX +XXX,XX @@ static int vhdx_create_bat(BlockBackend *blk, BDRVVHDXState *s, sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); vhdx_update_bat_table_entry(blk_bs(blk), s, &sinfo, &unused, &unused, block_state); - cpu_to_le64s(&s->bat[sinfo.bat_idx]); + s->bat[sinfo.bat_idx] = cpu_to_le64(s->bat[sinfo.bat_idx]); sector_num += s->sectors_per_block; } ret = blk_pwrite(blk, file_offset, s->bat, length, 0); -- 2.19.1 From: Peter Maydell <peter.maydell@linaro.org> Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. Patch produced with scripts/coccinelle/inplace-byteswaps.cocci. There are other places where we take the address of a packed member in this file for other purposes than passing it to a byteswap function (all the calls to qemu_uuid_*()); we leave those for now. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vdi.c | 64 ++++++++++++++++++++++++++--------------------------- 1 file changed, 32 insertions(+), 32 deletions(-) diff --git a/block/vdi.c b/block/vdi.c index XXXXXXX..XXXXXXX 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -XXX,XX +XXX,XX @@ typedef struct { static void vdi_header_to_cpu(VdiHeader *header) { - le32_to_cpus(&header->signature); - le32_to_cpus(&header->version); - le32_to_cpus(&header->header_size); - le32_to_cpus(&header->image_type); - le32_to_cpus(&header->image_flags); - le32_to_cpus(&header->offset_bmap); - le32_to_cpus(&header->offset_data); - le32_to_cpus(&header->cylinders); - le32_to_cpus(&header->heads); - le32_to_cpus(&header->sectors); - le32_to_cpus(&header->sector_size); - le64_to_cpus(&header->disk_size); - le32_to_cpus(&header->block_size); - le32_to_cpus(&header->block_extra); - le32_to_cpus(&header->blocks_in_image); - le32_to_cpus(&header->blocks_allocated); + header->signature = le32_to_cpu(header->signature); + header->version = le32_to_cpu(header->version); + header->header_size = le32_to_cpu(header->header_size); + header->image_type = le32_to_cpu(header->image_type); + header->image_flags = le32_to_cpu(header->image_flags); + header->offset_bmap = le32_to_cpu(header->offset_bmap); + header->offset_data = le32_to_cpu(header->offset_data); + header->cylinders = le32_to_cpu(header->cylinders); + header->heads = le32_to_cpu(header->heads); + header->sectors = le32_to_cpu(header->sectors); + header->sector_size = le32_to_cpu(header->sector_size); + header->disk_size = le64_to_cpu(header->disk_size); + header->block_size = le32_to_cpu(header->block_size); + header->block_extra = le32_to_cpu(header->block_extra); + header->blocks_in_image = le32_to_cpu(header->blocks_in_image); + header->blocks_allocated = le32_to_cpu(header->blocks_allocated); qemu_uuid_bswap(&header->uuid_image); qemu_uuid_bswap(&header->uuid_last_snap); qemu_uuid_bswap(&header->uuid_link); @@ -XXX,XX +XXX,XX @@ static void vdi_header_to_cpu(VdiHeader *header) static void vdi_header_to_le(VdiHeader *header) { - cpu_to_le32s(&header->signature); - cpu_to_le32s(&header->version); - cpu_to_le32s(&header->header_size); - cpu_to_le32s(&header->image_type); - cpu_to_le32s(&header->image_flags); - cpu_to_le32s(&header->offset_bmap); - cpu_to_le32s(&header->offset_data); - cpu_to_le32s(&header->cylinders); - cpu_to_le32s(&header->heads); - cpu_to_le32s(&header->sectors); - cpu_to_le32s(&header->sector_size); - cpu_to_le64s(&header->disk_size); - cpu_to_le32s(&header->block_size); - cpu_to_le32s(&header->block_extra); - cpu_to_le32s(&header->blocks_in_image); - cpu_to_le32s(&header->blocks_allocated); + header->signature = cpu_to_le32(header->signature); + header->version = cpu_to_le32(header->version); + header->header_size = cpu_to_le32(header->header_size); + header->image_type = cpu_to_le32(header->image_type); + header->image_flags = cpu_to_le32(header->image_flags); + header->offset_bmap = cpu_to_le32(header->offset_bmap); + header->offset_data = cpu_to_le32(header->offset_data); + header->cylinders = cpu_to_le32(header->cylinders); + header->heads = cpu_to_le32(header->heads); + header->sectors = cpu_to_le32(header->sectors); + header->sector_size = cpu_to_le32(header->sector_size); + header->disk_size = cpu_to_le64(header->disk_size); + header->block_size = cpu_to_le32(header->block_size); + header->block_extra = cpu_to_le32(header->block_extra); + header->blocks_in_image = cpu_to_le32(header->blocks_in_image); + header->blocks_allocated = cpu_to_le32(header->blocks_allocated); qemu_uuid_bswap(&header->uuid_image); qemu_uuid_bswap(&header->uuid_last_snap); qemu_uuid_bswap(&header->uuid_link); -- 2.19.1 From: Alberto Garcia <berto@igalia.com> This is a static function with only one caller, so there's no need to keep it. Inlining the code in quorum_compare() makes it much simpler. Signed-off-by: Alberto Garcia <berto@igalia.com> Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/quorum.c | 24 +++++------------------- 1 file changed, 5 insertions(+), 19 deletions(-) diff --git a/block/quorum.c b/block/quorum.c index XXXXXXX..XXXXXXX 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -XXX,XX +XXX,XX @@ static bool quorum_iovec_compare(QEMUIOVector *a, QEMUIOVector *b) return true; } -static void GCC_FMT_ATTR(2, 3) quorum_err(QuorumAIOCB *acb, - const char *fmt, ...) -{ - va_list ap; - - va_start(ap, fmt); - fprintf(stderr, "quorum: offset=%" PRIu64 " bytes=%" PRIu64 " ", - acb->offset, acb->bytes); - vfprintf(stderr, fmt, ap); - fprintf(stderr, "\n"); - va_end(ap); - exit(1); -} - -static bool quorum_compare(QuorumAIOCB *acb, - QEMUIOVector *a, - QEMUIOVector *b) +static bool quorum_compare(QuorumAIOCB *acb, QEMUIOVector *a, QEMUIOVector *b) { BDRVQuorumState *s = acb->bs->opaque; ssize_t offset; @@ -XXX,XX +XXX,XX @@ static bool quorum_compare(QuorumAIOCB *acb, if (s->is_blkverify) { offset = qemu_iovec_compare(a, b); if (offset != -1) { - quorum_err(acb, "contents mismatch at offset %" PRIu64, - acb->offset + offset); + fprintf(stderr, "quorum: offset=%" PRIu64 " bytes=%" PRIu64 + " contents mismatch at offset %" PRIu64 "\n", + acb->offset, acb->bytes, acb->offset + offset); + exit(1); } return true; } -- 2.19.1 From: Alberto Garcia <berto@igalia.com> The blkverify mode of Quorum can only be enabled if the number of children is exactly two and the value of vote-threshold is also two. If the user tries to enable it but the other settings are incorrect then QEMU simply prints an error message to stderr and carries on disabling the blkverify setting. This patch makes quorum_open() fail and return an error in this case. Signed-off-by: Alberto Garcia <berto@igalia.com> Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/quorum.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/block/quorum.c b/block/quorum.c index XXXXXXX..XXXXXXX 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -XXX,XX +XXX,XX @@ static int quorum_open(BlockDriverState *bs, QDict *options, int flags, s->read_pattern = ret; if (s->read_pattern == QUORUM_READ_PATTERN_QUORUM) { - /* is the driver in blkverify mode */ - if (qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false) && - s->num_children == 2 && s->threshold == 2) { - s->is_blkverify = true; - } else if (qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false)) { - fprintf(stderr, "blkverify mode is set by setting blkverify=on " - "and using two files with vote_threshold=2\n"); + s->is_blkverify = qemu_opt_get_bool(opts, QUORUM_OPT_BLKVERIFY, false); + if (s->is_blkverify && (s->num_children != 2 || s->threshold != 2)) { + error_setg(&local_err, "blkverify=on can only be set if there are " + "exactly two files and vote-threshold is 2"); + ret = -EINVAL; + goto exit; } s->rewrite_corrupted = qemu_opt_get_bool(opts, QUORUM_OPT_REWRITE, -- 2.19.1 From: Alberto Garcia <berto@igalia.com> Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/081 | 30 ++++++++++++++++++++++++++++++ tests/qemu-iotests/081.out | 16 ++++++++++++++++ 2 files changed, 46 insertions(+) diff --git a/tests/qemu-iotests/081 b/tests/qemu-iotests/081 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/081 +++ b/tests/qemu-iotests/081 @@ -XXX,XX +XXX,XX @@ echo "== checking that quorum is broken ==" $QEMU_IO -c "open -o $quorum" -c "read -P 0x32 0 $size" | _filter_qemu_io +echo +echo "== checking the blkverify mode with broken content ==" + +quorum="driver=raw,file.driver=quorum,file.vote-threshold=2,file.blkverify=on" +quorum="$quorum,file.children.0.file.filename=$TEST_DIR/1.raw" +quorum="$quorum,file.children.1.file.filename=$TEST_DIR/2.raw" +quorum="$quorum,file.children.0.driver=raw" +quorum="$quorum,file.children.1.driver=raw" + +$QEMU_IO -c "open -o $quorum" -c "read -P 0x32 0 $size" | _filter_qemu_io + +echo +echo "== writing the same data to both files ==" + +$QEMU_IO -c "write -P 0x32 0 $size" "$TEST_DIR/1.raw" | _filter_qemu_io +$QEMU_IO -c "write -P 0x32 0 $size" "$TEST_DIR/2.raw" | _filter_qemu_io + +echo +echo "== checking the blkverify mode with valid content ==" + +$QEMU_IO -c "open -o $quorum" -c "read -P 0x32 0 $size" | _filter_qemu_io + +echo +echo "== checking the blkverify mode with invalid settings ==" + +quorum="$quorum,file.children.2.file.filename=$TEST_DIR/3.raw" +quorum="$quorum,file.children.2.driver=raw" + +$QEMU_IO -c "open -o $quorum" | _filter_qemu_io + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/081.out b/tests/qemu-iotests/081.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/081.out +++ b/tests/qemu-iotests/081.out @@ -XXX,XX +XXX,XX @@ wrote 10485760/10485760 bytes at offset 0 == checking that quorum is broken == read failed: Input/output error + +== checking the blkverify mode with broken content == +quorum: offset=0 bytes=10485760 contents mismatch at offset 0 + +== writing the same data to both files == +wrote 10485760/10485760 bytes at offset 0 +10 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 10485760/10485760 bytes at offset 0 +10 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +== checking the blkverify mode with valid content == +read 10485760/10485760 bytes at offset 0 +10 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) + +== checking the blkverify mode with invalid settings == +can't open: blkverify=on can only be set if there are exactly two files and vote-threshold is 2 *** done -- 2.19.1 From: Alberto Garcia <berto@igalia.com> The blkverify mode of Quorum only works when the number of children is exactly two, so any attempt to add a new one must return an error. quorum_del_child() on the other hand doesn't need any additional check because decreasing the number of children would make it go under the vote threshold. Signed-off-by: Alberto Garcia <berto@igalia.com> Reported-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/quorum.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/block/quorum.c b/block/quorum.c index XXXXXXX..XXXXXXX 100644 --- a/block/quorum.c +++ b/block/quorum.c @@ -XXX,XX +XXX,XX @@ static void quorum_add_child(BlockDriverState *bs, BlockDriverState *child_bs, char indexstr[32]; int ret; + if (s->is_blkverify) { + error_setg(errp, "Cannot add a child to a quorum in blkverify mode"); + return; + } + assert(s->num_children <= INT_MAX / sizeof(BdrvChild *)); if (s->num_children == INT_MAX / sizeof(BdrvChild *) || s->next_child_index == UINT_MAX) { @@ -XXX,XX +XXX,XX @@ static void quorum_del_child(BlockDriverState *bs, BdrvChild *child, return; } + /* We know now that num_children > threshold, so blkverify must be false */ + assert(!s->is_blkverify); + bdrv_drained_begin(bs); /* We can safely remove this child now */ -- 2.19.1 From: Alberto Garcia <berto@igalia.com> This patch tests that you can add and remove drives from a Quorum using the x-blockdev-change command. Signed-off-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/081 | 86 ++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/081.out | 54 ++++++++++++++++++++++++ 2 files changed, 140 insertions(+) diff --git a/tests/qemu-iotests/081 b/tests/qemu-iotests/081 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/081 +++ b/tests/qemu-iotests/081 @@ -XXX,XX +XXX,XX @@ quorum="$quorum,file.children.2.driver=raw" $QEMU_IO -c "open -o $quorum" | _filter_qemu_io +echo +echo "== dynamically adding a child to a quorum ==" + +for verify in false true; do + run_qemu <<EOF + { "execute": "qmp_capabilities" } + { "execute": "blockdev-add", + "arguments": { + "driver": "quorum", + "node-name": "drive0-quorum", + "vote-threshold": 2, + "blkverify": ${verify}, + "children": [ + { + "driver": "$IMGFMT", + "file": { + "driver": "file", + "filename": "$TEST_DIR/1.raw" + } + }, + { + "driver": "$IMGFMT", + "file": { + "driver": "file", + "filename": "$TEST_DIR/2.raw" + } + } + ] + } + } + { "execute": "blockdev-add", + "arguments": { + "node-name": "drive3", + "driver": "$IMGFMT", + "file": { + "driver": "file", + "filename": "$TEST_DIR/2.raw" + } + } + } + { "execute": "x-blockdev-change", + "arguments": { "parent": "drive0-quorum", + "node": "drive3" } } + { "execute": "quit" } +EOF +done + +echo +echo "== dynamically removing a child from a quorum ==" + +for verify in false true; do + for vote_threshold in 1 2; do + run_qemu <<EOF + { "execute": "qmp_capabilities" } + { "execute": "blockdev-add", + "arguments": { + "driver": "quorum", + "node-name": "drive0-quorum", + "vote-threshold": ${vote_threshold}, + "blkverify": ${verify}, + "children": [ + { + "driver": "$IMGFMT", + "file": { + "driver": "file", + "filename": "$TEST_DIR/1.raw" + } + }, + { + "driver": "$IMGFMT", + "file": { + "driver": "file", + "filename": "$TEST_DIR/2.raw" + } + } + ] + } + } + { "execute": "x-blockdev-change", + "arguments": { "parent": "drive0-quorum", + "child": "children.1" } } + { "execute": "quit" } +EOF + done +done + # success, all done echo "*** done" rm -f $seq.full diff --git a/tests/qemu-iotests/081.out b/tests/qemu-iotests/081.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/081.out +++ b/tests/qemu-iotests/081.out @@ -XXX,XX +XXX,XX @@ read 10485760/10485760 bytes at offset 0 == checking the blkverify mode with invalid settings == can't open: blkverify=on can only be set if there are exactly two files and vote-threshold is 2 + +== dynamically adding a child to a quorum == +Testing: +QMP_VERSION +{"return": {}} +{"return": {}} +{"return": {}} +{"return": {}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + +Testing: +QMP_VERSION +{"return": {}} +{"return": {}} +{"return": {}} +{"error": {"class": "GenericError", "desc": "Cannot add a child to a quorum in blkverify mode"}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + + +== dynamically removing a child from a quorum == +Testing: +QMP_VERSION +{"return": {}} +{"return": {}} +{"return": {}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + +Testing: +QMP_VERSION +{"return": {}} +{"return": {}} +{"error": {"class": "GenericError", "desc": "The number of children cannot be lower than the vote threshold 2"}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + +Testing: +QMP_VERSION +{"return": {}} +{"error": {"class": "GenericError", "desc": "blkverify=on can only be set if there are exactly two files and vote-threshold is 2"}} +{"error": {"class": "GenericError", "desc": "Cannot find device=drive0-quorum nor node_name=drive0-quorum"}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + +Testing: +QMP_VERSION +{"return": {}} +{"return": {}} +{"error": {"class": "GenericError", "desc": "The number of children cannot be lower than the vote threshold 2"}} +{"return": {}} +{"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false}} + *** done -- 2.19.1 To fully change the read-only state of a node, we must not only change bs->read_only, but also update bs->open_flags. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> --- block.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp) } bs->read_only = read_only; + + if (read_only) { + bs->open_flags &= ~BDRV_O_RDWR; + } else { + bs->open_flags |= BDRV_O_RDWR; + } + return 0; } -- 2.19.1 If a management application builds the block graph node by node, the protocol layer doesn't inherit its read-only option from the format layer any more, so it must be set explicitly. Backing files should work on read-only storage, but at the same time, a block job like commit should be able to reopen them read-write if they are on read-write storage. However, without option inheritance, reopen only changes the read-only option for the root node (typically the format layer), but not the protocol layer, so reopening fails (the format layer wants to get write permissions, but the protocol layer is still read-only). A simple workaround for the problem in the management tool would be to open the protocol layer always read-write and to make only the format layer read-only for backing files. However, sometimes the file is actually stored on read-only storage and we don't know whether the image can be opened read-write (for example, for NBD it depends on the server we're trying to connect to). This adds an option that makes QEMU try to open the image read-write, but allows it to degrade to a read-only mode without returning an error. The documentation for this option is consciously phrased in a way that allows QEMU to switch to a better model eventually: Instead of trying when the image is first opened, making the read-only flag dynamic and changing it automatically whenever the first BLK_PERM_WRITE user is attached or the last one is detached would be much more useful behaviour. Unfortunately, this more useful behaviour is also a lot harder to implement, and libvirt needs a solution now before it can switch to -blockdev, so let's start with this easier approach for now. Instead of adding a new auto-read-only option, turning the existing read-only into an enum (with a bool alternate for compatibility) was considered, but it complicated the implementation to the point that it didn't seem to be worth it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- qapi/block-core.json | 7 +++++++ include/block/block.h | 2 ++ block.c | 17 +++++++++++++++++ block/vvfat.c | 1 + blockdev.c | 2 +- 5 files changed, 28 insertions(+), 1 deletion(-) diff --git a/qapi/block-core.json b/qapi/block-core.json index XXXXXXX..XXXXXXX 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -XXX,XX +XXX,XX @@ # either generally or in certain configurations. In this case, # the default value does not work and the option must be # specified explicitly. +# @auto-read-only: if true and @read-only is false, QEMU may automatically +# decide not to open the image read-write as requested, but +# fall back to read-only instead (and switch between the modes +# later), e.g. depending on whether the image file is writable +# or whether a writing user is attached to the node +# (default: false, since 3.1) # @detect-zeroes: detect and optimize zero writes (Since 2.1) # (default: off) # @force-share: force share all permission on added nodes. @@ -XXX,XX +XXX,XX @@ '*discard': 'BlockdevDiscardOptions', '*cache': 'BlockdevCacheOptions', '*read-only': 'bool', + '*auto-read-only': 'bool', '*force-share': 'bool', '*detect-zeroes': 'BlockdevDetectZeroesOptions' }, 'discriminator': 'driver', diff --git a/include/block/block.h b/include/block/block.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -XXX,XX +XXX,XX @@ typedef struct HDGeometry { select an appropriate protocol driver, ignoring the format layer */ #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ +#define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */ #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) @@ -XXX,XX +XXX,XX @@ typedef struct HDGeometry { #define BDRV_OPT_CACHE_DIRECT "cache.direct" #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" #define BDRV_OPT_READ_ONLY "read-only" +#define BDRV_OPT_AUTO_READ_ONLY "auto-read-only" #define BDRV_OPT_DISCARD "discard" #define BDRV_OPT_FORCE_SHARE "force-share" diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_inherited_options(int *child_flags, QDict *child_options, /* Inherit the read-only option from the parent if it's not set */ qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); + qdict_copy_default(child_options, parent_options, BDRV_OPT_AUTO_READ_ONLY); /* Our block drivers take care to send flushes and respect unmap policy, * so we can default to enable both on lower layers regardless of the @@ -XXX,XX +XXX,XX @@ static void bdrv_backing_options(int *child_flags, QDict *child_options, /* backing files always opened read-only */ qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "on"); + qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); flags &= ~BDRV_O_COPY_ON_READ; /* snapshot=on is handled on the top layer */ @@ -XXX,XX +XXX,XX @@ static void update_flags_from_options(int *flags, QemuOpts *opts) *flags |= BDRV_O_RDWR; } + assert(qemu_opt_find(opts, BDRV_OPT_AUTO_READ_ONLY)); + if (qemu_opt_get_bool_del(opts, BDRV_OPT_AUTO_READ_ONLY, false)) { + *flags |= BDRV_O_AUTO_RDONLY; + } } static void update_options_from_flags(QDict *options, int flags) @@ -XXX,XX +XXX,XX @@ static void update_options_from_flags(QDict *options, int flags) if (!qdict_haskey(options, BDRV_OPT_READ_ONLY)) { qdict_put_bool(options, BDRV_OPT_READ_ONLY, !(flags & BDRV_O_RDWR)); } + if (!qdict_haskey(options, BDRV_OPT_AUTO_READ_ONLY)) { + qdict_put_bool(options, BDRV_OPT_AUTO_READ_ONLY, + flags & BDRV_O_AUTO_RDONLY); + } } static void bdrv_assign_node_name(BlockDriverState *bs, @@ -XXX,XX +XXX,XX @@ QemuOptsList bdrv_runtime_opts = { .type = QEMU_OPT_BOOL, .help = "Node is opened in read-only mode", }, + { + .name = BDRV_OPT_AUTO_READ_ONLY, + .type = QEMU_OPT_BOOL, + .help = "Node can become read-only if opening read-write fails", + }, { .name = "detect-zeroes", .type = QEMU_OPT_STRING, @@ -XXX,XX +XXX,XX @@ BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp) qdict_set_default_str(qdict, BDRV_OPT_CACHE_DIRECT, "off"); qdict_set_default_str(qdict, BDRV_OPT_CACHE_NO_FLUSH, "off"); qdict_set_default_str(qdict, BDRV_OPT_READ_ONLY, "off"); + qdict_set_default_str(qdict, BDRV_OPT_AUTO_READ_ONLY, "off"); + } bs = bdrv_open_inherit(NULL, reference, qdict, 0, NULL, NULL, errp); diff --git a/block/vvfat.c b/block/vvfat.c index XXXXXXX..XXXXXXX 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -XXX,XX +XXX,XX @@ static void vvfat_qcow_options(int *child_flags, QDict *child_options, int parent_flags, QDict *parent_options) { qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "off"); + qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); } diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_change_medium(bool has_device, const char *device, bdrv_flags = blk_get_open_flags_from_root_state(blk); bdrv_flags &= ~(BDRV_O_TEMPORARY | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | - BDRV_O_PROTOCOL); + BDRV_O_PROTOCOL | BDRV_O_AUTO_RDONLY); if (!has_read_only) { read_only = BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN; -- 2.19.1 Commit e2b8247a322 introduced an error path in qemu_rbd_open() after calling rbd_open(), but neglected to close the image again in this error path. The error path should contain everything that the regular close function qemu_rbd_close() contains. This adds the missing rbd_close() call. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- block/rbd.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/rbd.c b/block/rbd.c index XXXXXXX..XXXXXXX 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, "automatically marking the image read-only."); r = bdrv_set_read_only(bs, true, &local_err); if (r < 0) { + rbd_close(s->image); error_propagate(errp, local_err); goto failed_open; } -- 2.19.1 Some block drivers have traditionally changed their node to read-only mode without asking the user. This behaviour has been marked deprecated since 2.11, expecting users to provide an explicit read-only=on option. Now that we have auto-read-only=on, enable these drivers to make use of the option. This is the only use of bdrv_set_read_only(), so we can make it a bit more specific and turn it into a bdrv_apply_auto_read_only() that is more convenient for drivers to use. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- include/block/block.h | 3 ++- block.c | 42 +++++++++++++++++++++++++++--------------- block/bochs.c | 17 ++++++----------- block/cloop.c | 16 +++++----------- block/dmg.c | 16 +++++----------- block/rbd.c | 15 ++++----------- block/vvfat.c | 10 ++-------- 7 files changed, 51 insertions(+), 68 deletions(-) diff --git a/include/block/block.h b/include/block/block.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -XXX,XX +XXX,XX @@ int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, bool bdrv_is_read_only(BlockDriverState *bs); int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, bool ignore_allow_rdw, Error **errp); -int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp); +int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, + Error **errp); bool bdrv_is_writable(BlockDriverState *bs); bool bdrv_is_sg(BlockDriverState *bs); bool bdrv_is_inserted(BlockDriverState *bs); diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, return 0; } -/* TODO Remove (deprecated since 2.11) - * Block drivers are not supposed to automatically change bs->read_only. - * Instead, they should just check whether they can provide what the user - * explicitly requested and error out if read-write is requested, but they can - * only provide read-only access. */ -int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp) +/* + * Called by a driver that can only provide a read-only image. + * + * Returns 0 if the node is already read-only or it could switch the node to + * read-only because BDRV_O_AUTO_RDONLY is set. + * + * Returns -EACCES if the node is read-write and BDRV_O_AUTO_RDONLY is not set + * or bdrv_can_set_read_only() forbids making the node read-only. If @errmsg + * is not NULL, it is used as the error message for the Error object. + */ +int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, + Error **errp) { int ret = 0; - ret = bdrv_can_set_read_only(bs, read_only, false, errp); - if (ret < 0) { - return ret; + if (!(bs->open_flags & BDRV_O_RDWR)) { + return 0; + } + if (!(bs->open_flags & BDRV_O_AUTO_RDONLY)) { + goto fail; } - bs->read_only = read_only; - - if (read_only) { - bs->open_flags &= ~BDRV_O_RDWR; - } else { - bs->open_flags |= BDRV_O_RDWR; + ret = bdrv_can_set_read_only(bs, true, false, NULL); + if (ret < 0) { + goto fail; } + bs->read_only = true; + bs->open_flags &= ~BDRV_O_RDWR; + return 0; + +fail: + error_setg(errp, "%s", errmsg ?: "Image is read-only"); + return -EACCES; } void bdrv_get_full_backing_filename_from_filename(const char *backed, diff --git a/block/bochs.c b/block/bochs.c index XXXXXXX..XXXXXXX 100644 --- a/block/bochs.c +++ b/block/bochs.c @@ -XXX,XX +XXX,XX @@ static int bochs_open(BlockDriverState *bs, QDict *options, int flags, struct bochs_header bochs; int ret; + /* No write support yet */ + ret = bdrv_apply_auto_read_only(bs, NULL, errp); + if (ret < 0) { + return ret; + } + bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, errp); if (!bs->file) { return -EINVAL; } - if (!bdrv_is_read_only(bs)) { - error_report("Opening bochs images without an explicit read-only=on " - "option is deprecated. Future versions will refuse to " - "open the image instead of automatically marking the " - "image read-only."); - ret = bdrv_set_read_only(bs, true, errp); /* no write support yet */ - if (ret < 0) { - return ret; - } - } - ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs)); if (ret < 0) { return ret; diff --git a/block/cloop.c b/block/cloop.c index XXXXXXX..XXXXXXX 100644 --- a/block/cloop.c +++ b/block/cloop.c @@ -XXX,XX +XXX,XX @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags, uint32_t offsets_size, max_compressed_block_size = 1, i; int ret; + ret = bdrv_apply_auto_read_only(bs, NULL, errp); + if (ret < 0) { + return ret; + } + bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, errp); if (!bs->file) { return -EINVAL; } - if (!bdrv_is_read_only(bs)) { - error_report("Opening cloop images without an explicit read-only=on " - "option is deprecated. Future versions will refuse to " - "open the image instead of automatically marking the " - "image read-only."); - ret = bdrv_set_read_only(bs, true, errp); - if (ret < 0) { - return ret; - } - } - /* read header */ ret = bdrv_pread(bs->file, 128, &s->block_size, 4); if (ret < 0) { diff --git a/block/dmg.c b/block/dmg.c index XXXXXXX..XXXXXXX 100644 --- a/block/dmg.c +++ b/block/dmg.c @@ -XXX,XX +XXX,XX @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags, int64_t offset; int ret; + ret = bdrv_apply_auto_read_only(bs, NULL, errp); + if (ret < 0) { + return ret; + } + bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file, false, errp); if (!bs->file) { return -EINVAL; } - if (!bdrv_is_read_only(bs)) { - error_report("Opening dmg images without an explicit read-only=on " - "option is deprecated. Future versions will refuse to " - "open the image instead of automatically marking the " - "image read-only."); - ret = bdrv_set_read_only(bs, true, errp); - if (ret < 0) { - return ret; - } - } - block_module_load_one("dmg-bz2"); s->n_chunks = 0; diff --git a/block/rbd.c b/block/rbd.c index XXXXXXX..XXXXXXX 100644 --- a/block/rbd.c +++ b/block/rbd.c @@ -XXX,XX +XXX,XX @@ static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags, /* If we are using an rbd snapshot, we must be r/o, otherwise * leave as-is */ if (s->snap != NULL) { - if (!bdrv_is_read_only(bs)) { - error_report("Opening rbd snapshots without an explicit " - "read-only=on option is deprecated. Future versions " - "will refuse to open the image instead of " - "automatically marking the image read-only."); - r = bdrv_set_read_only(bs, true, &local_err); - if (r < 0) { - rbd_close(s->image); - error_propagate(errp, local_err); - goto failed_open; - } + r = bdrv_apply_auto_read_only(bs, "rbd snapshots are read-only", errp); + if (r < 0) { + rbd_close(s->image); + goto failed_open; } } diff --git a/block/vvfat.c b/block/vvfat.c index XXXXXXX..XXXXXXX 100644 --- a/block/vvfat.c +++ b/block/vvfat.c @@ -XXX,XX +XXX,XX @@ static int vvfat_open(BlockDriverState *bs, QDict *options, int flags, "Unable to set VVFAT to 'rw' when drive is read-only"); goto fail; } - } else if (!bdrv_is_read_only(bs)) { - error_report("Opening non-rw vvfat images without an explicit " - "read-only=on option is deprecated. Future versions " - "will refuse to open the image instead of " - "automatically marking the image read-only."); - /* read only is the default for safety */ - ret = bdrv_set_read_only(bs, true, &local_err); + } else { + ret = bdrv_apply_auto_read_only(bs, NULL, errp); if (ret < 0) { - error_propagate(errp, local_err); goto fail; } } -- 2.19.1 If read-only=off, but auto-read-only=on is given, open a read-write NBD connection if the server provides a read-write export, but instead of erroring out for read-only exports, just degrade to read-only. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- block/nbd-client.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/block/nbd-client.c b/block/nbd-client.c index XXXXXXX..XXXXXXX 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -XXX,XX +XXX,XX @@ int nbd_client_init(BlockDriverState *bs, logout("Failed to negotiate with the NBD server\n"); return ret; } - if (client->info.flags & NBD_FLAG_READ_ONLY && - !bdrv_is_read_only(bs)) { - error_setg(errp, - "request for write access conflicts with read-only export"); - return -EACCES; + if (client->info.flags & NBD_FLAG_READ_ONLY) { + ret = bdrv_apply_auto_read_only(bs, "NBD export is read-only", errp); + if (ret < 0) { + return ret; + } } if (client->info.flags & NBD_FLAG_SEND_FUA) { bs->supported_write_flags = BDRV_REQ_FUA; -- 2.19.1 If read-only=off, but auto-read-only=on is given, open the file read-write if we have the permissions, but instead of erroring out for read-only files, just degrade to read-only. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- block/file-posix.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/block/file-posix.c b/block/file-posix.c index XXXXXXX..XXXXXXX 100644 --- a/block/file-posix.c +++ b/block/file-posix.c @@ -XXX,XX +XXX,XX @@ static int raw_open_common(BlockDriverState *bs, QDict *options, s->fd = -1; fd = qemu_open(filename, s->open_flags, 0644); - if (fd < 0) { - ret = -errno; - error_setg_errno(errp, errno, "Could not open '%s'", filename); + ret = fd < 0 ? -errno : 0; + + if (ret == -EACCES || ret == -EROFS) { + /* Try to degrade to read-only, but if it doesn't work, still use the + * normal error message. */ + if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { + bdrv_flags &= ~BDRV_O_RDWR; + raw_parse_flags(bdrv_flags, &s->open_flags); + assert(!(s->open_flags & O_CREAT)); + fd = qemu_open(filename, s->open_flags); + ret = fd < 0 ? -errno : 0; + } + } + + if (ret < 0) { + error_setg_errno(errp, -ret, "Could not open '%s'", filename); if (ret == -EROFS) { ret = -EACCES; } -- 2.19.1 If read-only=off, but auto-read-only=on is given, just degrade to read-only. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- block/curl.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/block/curl.c b/block/curl.c index XXXXXXX..XXXXXXX 100644 --- a/block/curl.c +++ b/block/curl.c @@ -XXX,XX +XXX,XX @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags, const char *protocol_delimiter; int ret; - - if (flags & BDRV_O_RDWR) { - error_setg(errp, "curl block device does not support writes"); - return -EROFS; + ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes", + errp); + if (ret < 0) { + return ret; } if (!libcurl_initialized) { -- 2.19.1 If read-only=off, but auto-read-only=on is given, open the file read-write if we have the permissions, but instead of erroring out for read-only files, just degrade to read-only. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Niels de Vos <ndevos@redhat.com> --- block/gluster.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/block/gluster.c b/block/gluster.c index XXXXXXX..XXXXXXX 100644 --- a/block/gluster.c +++ b/block/gluster.c @@ -XXX,XX +XXX,XX @@ static int qemu_gluster_open(BlockDriverState *bs, QDict *options, qemu_gluster_parse_flags(bdrv_flags, &open_flags); s->fd = glfs_open(s->glfs, gconf->path, open_flags); - if (!s->fd) { - ret = -errno; + ret = s->fd ? 0 : -errno; + + if (ret == -EACCES || ret == -EROFS) { + /* Try to degrade to read-only, but if it doesn't work, still use the + * normal error message. */ + if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { + open_flags = (open_flags & ~O_RDWR) | O_RDONLY; + s->fd = glfs_open(s->glfs, gconf->path, open_flags); + ret = s->fd ? 0 : -errno; + } } s->supports_seek_data = qemu_gluster_test_seek(s->fd); -- 2.19.1 If read-only=off, but auto-read-only=on is given, open the volume read-write if we have the permissions, but instead of erroring out for read-only volumes, just degrade to read-only. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- block/iscsi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/block/iscsi.c b/block/iscsi.c index XXXXXXX..XXXXXXX 100644 --- a/block/iscsi.c +++ b/block/iscsi.c @@ -XXX,XX +XXX,XX @@ static int iscsi_open(BlockDriverState *bs, QDict *options, int flags, /* Check the write protect flag of the LUN if we want to write */ if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) && iscsilun->write_protected) { - error_setg(errp, "Cannot open a write protected LUN as read-write"); - ret = -EACCES; - goto out; + ret = bdrv_apply_auto_read_only(bs, "LUN is write protected", errp); + if (ret < 0) { + goto out; + } + flags &= ~BDRV_O_RDWR; } iscsi_readcapacity_sync(iscsilun, &local_err); -- 2.19.1 While we want machine interfaces like -blockdev and QMP blockdev-add to add as little auto-detection as possible so that management tools are explicit about their needs, -drive is a convenience option for human users. Enabling auto-read-only=on by default there enables users to use read-only images for read-only guest devices without having to specify read-only=on explicitly. If they try to attach the image to a read-write device, they will still get an error message. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- blockdev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ static BlockBackend *blockdev_init(const char *file, QDict *bs_opts, qdict_set_default_str(bs_opts, BDRV_OPT_CACHE_NO_FLUSH, "off"); qdict_set_default_str(bs_opts, BDRV_OPT_READ_ONLY, read_only ? "on" : "off"); + qdict_set_default_str(bs_opts, BDRV_OPT_AUTO_READ_ONLY, "on"); assert((bdrv_flags & BDRV_O_CACHE_MASK) == 0); if (runstate_check(RUN_STATE_INMIGRATE)) { -- 2.19.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> --- tests/qemu-iotests/232 | 147 +++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/232.out | 59 +++++++++++++++ tests/qemu-iotests/group | 1 + 3 files changed, 207 insertions(+) create mode 100755 tests/qemu-iotests/232 create mode 100644 tests/qemu-iotests/232.out diff --git a/tests/qemu-iotests/232 b/tests/qemu-iotests/232 new file mode 100755 index XXXXXXX..XXXXXXX --- /dev/null +++ b/tests/qemu-iotests/232 @@ -XXX,XX +XXX,XX @@ +#!/bin/bash +# +# Test for auto-read-only +# +# Copyright (C) 2018 Red Hat, Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. +# + +# creator +owner=kwolf@redhat.com + +seq=`basename $0` +echo "QA output created by $seq" + +here=`pwd` +status=1 # failure is the default! + +_cleanup() +{ + _cleanup_test_img + rm -f $TEST_IMG.snap +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common.rc +. ./common.filter + +_supported_fmt generic +_supported_proto file +_supported_os Linux + +function do_run_qemu() +{ + echo Testing: "$@" + ( + if ! test -t 0; then + while read cmd; do + echo $cmd + done + fi + echo quit + ) | $QEMU -nographic -monitor stdio -nodefaults "$@" + echo +} + +function run_qemu() +{ + do_run_qemu "$@" 2>&1 | _filter_testdir | _filter_qemu | _filter_hmp | + _filter_generated_node_ids | _filter_imgfmt +} + +function run_qemu_info_block() +{ + echo "info block -n" | run_qemu "$@" | grep -e "(file" -e "QEMU_PROG" +} + +size=128M + +_make_test_img $size + +echo +echo "=== -drive with read-write image: read-only/auto-read-only combinations ===" +echo + +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on +echo +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off +echo +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none + +echo +echo "=== -drive with read-only image: read-only/auto-read-only combinations ===" +echo + +chmod a-w $TEST_IMG + +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=on +echo +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,read-only=off +echo +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,auto-read-only=off +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none,auto-read-only=on +run_qemu_info_block -drive driver=file,file="$TEST_IMG",if=none + +echo +echo "=== -blockdev with read-write image: read-only/auto-read-only combinations ===" +echo + +chmod a+w $TEST_IMG + +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on +echo +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off +echo +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0 + +echo +echo "=== -blockdev with read-only image: read-only/auto-read-only combinations ===" +echo + +chmod a-w $TEST_IMG + +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=on +echo +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,read-only=off +echo +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,auto-read-only=off +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0,auto-read-only=on +run_qemu_info_block -blockdev driver=file,filename="$TEST_IMG",node-name=node0 + +# success, all done +echo "*** done" +rm -f $seq.full +status=0 diff --git a/tests/qemu-iotests/232.out b/tests/qemu-iotests/232.out new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/tests/qemu-iotests/232.out @@ -XXX,XX +XXX,XX @@ +QA output created by 232 +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 + +=== -drive with read-write image: read-only/auto-read-only combinations === + +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) + +NODE_NAME: TEST_DIR/t.IMGFMT (file) +NODE_NAME: TEST_DIR/t.IMGFMT (file) +NODE_NAME: TEST_DIR/t.IMGFMT (file) + +NODE_NAME: TEST_DIR/t.IMGFMT (file) +NODE_NAME: TEST_DIR/t.IMGFMT (file) +NODE_NAME: TEST_DIR/t.IMGFMT (file) + +=== -drive with read-only image: read-only/auto-read-only combinations === + +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) + +QEMU_PROG: -drive driver=file,file=TEST_DIR/t.IMGFMT,if=none,read-only=off,auto-read-only=off: Could not open 'TEST_DIR/t.IMGFMT': Permission denied +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) + +QEMU_PROG: -drive driver=file,file=TEST_DIR/t.IMGFMT,if=none,auto-read-only=off: Could not open 'TEST_DIR/t.IMGFMT': Permission denied +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) +NODE_NAME: TEST_DIR/t.IMGFMT (file, read-only) + +=== -blockdev with read-write image: read-only/auto-read-only combinations === + +node0: TEST_DIR/t.IMGFMT (file, read-only) +node0: TEST_DIR/t.IMGFMT (file, read-only) +node0: TEST_DIR/t.IMGFMT (file, read-only) + +node0: TEST_DIR/t.IMGFMT (file) +node0: TEST_DIR/t.IMGFMT (file) +node0: TEST_DIR/t.IMGFMT (file) + +node0: TEST_DIR/t.IMGFMT (file) +node0: TEST_DIR/t.IMGFMT (file) +node0: TEST_DIR/t.IMGFMT (file) + +=== -blockdev with read-only image: read-only/auto-read-only combinations === + +node0: TEST_DIR/t.IMGFMT (file, read-only) +node0: TEST_DIR/t.IMGFMT (file, read-only) +node0: TEST_DIR/t.IMGFMT (file, read-only) + +QEMU_PROG: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=node0,read-only=off,auto-read-only=off: Could not open 'TEST_DIR/t.IMGFMT': Permission denied +node0: TEST_DIR/t.IMGFMT (file, read-only) +QEMU_PROG: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=node0,read-only=off: Could not open 'TEST_DIR/t.IMGFMT': Permission denied + +QEMU_PROG: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=node0,auto-read-only=off: Could not open 'TEST_DIR/t.IMGFMT': Permission denied +node0: TEST_DIR/t.IMGFMT (file, read-only) +QEMU_PROG: -blockdev driver=file,filename=TEST_DIR/t.IMGFMT,node-name=node0: Could not open 'TEST_DIR/t.IMGFMT': Permission denied +*** done diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/group +++ b/tests/qemu-iotests/group @@ -XXX,XX +XXX,XX @@ 227 auto quick 229 auto quick 231 auto quick +232 auto quick -- 2.19.1 From: Max Reitz <mreitz@redhat.com> This adds some whitespace into the option help (including indentation) and puts angle brackets around the type names. Furthermore, the list name is no longer printed as part of every line, but only once in advance, and only if the caller did not print a caption already. This patch also restores the description alignment we had before commit 9cbef9d68ee1d8d0, just at 24 instead of 16 characters like we used to. This increase is because now we have the type and two spaces of indentation before the description, and with a usual type name length of three chracters, this sums up to eight additional characters -- which means that we now need 24 characters to get the same amount of padding for most options. Also, 24 is a third of 80, which makes it kind of a round number in terminal terms. Finally, this patch amends the reference output of iotest 082 to match the changes (and thus makes it pass again). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/qemu/option.h | 2 +- qemu-img.c | 4 +- util/qemu-option.c | 32 +- tests/qemu-iotests/082.out | 956 ++++++++++++++++++------------------- 4 files changed, 507 insertions(+), 487 deletions(-) diff --git a/include/qemu/option.h b/include/qemu/option.h index XXXXXXX..XXXXXXX 100644 --- a/include/qemu/option.h +++ b/include/qemu/option.h @@ -XXX,XX +XXX,XX @@ typedef int (*qemu_opts_loopfunc)(void *opaque, QemuOpts *opts, Error **errp); int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque, Error **errp); void qemu_opts_print(QemuOpts *opts, const char *sep); -void qemu_opts_print_help(QemuOptsList *list); +void qemu_opts_print_help(QemuOptsList *list, bool print_caption); void qemu_opts_free(QemuOptsList *list); QemuOptsList *qemu_opts_append(QemuOptsList *dst, QemuOptsList *list); diff --git a/qemu-img.c b/qemu-img.c index XXXXXXX..XXXXXXX 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -XXX,XX +XXX,XX @@ static int print_block_option_help(const char *filename, const char *fmt) } printf("Supported options:\n"); - qemu_opts_print_help(create_opts); + qemu_opts_print_help(create_opts, false); qemu_opts_free(create_opts); return 0; } @@ -XXX,XX +XXX,XX @@ static int print_amend_option_help(const char *format) assert(drv->create_opts); printf("Creation options for '%s':\n", format); - qemu_opts_print_help(drv->create_opts); + qemu_opts_print_help(drv->create_opts, false); printf("\nNote that not all of these options may be amendable.\n"); return 0; } diff --git a/util/qemu-option.c b/util/qemu-option.c index XXXXXXX..XXXXXXX 100644 --- a/util/qemu-option.c +++ b/util/qemu-option.c @@ -XXX,XX +XXX,XX @@ static const char *opt_type_to_string(enum QemuOptType type) g_assert_not_reached(); } -void qemu_opts_print_help(QemuOptsList *list) +/** + * Print the list of options available in the given list. If + * @print_caption is true, a caption (including the list name, if it + * exists) is printed. The options itself will be indented, so + * @print_caption should only be set to false if the caller prints its + * own custom caption (so that the indentation makes sense). + */ +void qemu_opts_print_help(QemuOptsList *list, bool print_caption) { QemuOptDesc *desc; int i; @@ -XXX,XX +XXX,XX @@ void qemu_opts_print_help(QemuOptsList *list) desc = list->desc; while (desc && desc->name) { GString *str = g_string_new(NULL); - if (list->name) { - g_string_append_printf(str, "%s.", list->name); - } - g_string_append_printf(str, "%s=%s", desc->name, + g_string_append_printf(str, " %s=<%s>", desc->name, opt_type_to_string(desc->type)); if (desc->help) { + if (str->len < 24) { + g_string_append_printf(str, "%*s", 24 - (int)str->len, ""); + } g_string_append_printf(str, " - %s", desc->help); } g_ptr_array_add(array, g_string_free(str, false)); @@ -XXX,XX +XXX,XX @@ void qemu_opts_print_help(QemuOptsList *list) } g_ptr_array_sort(array, (GCompareFunc)qemu_pstrcmp0); + if (print_caption && array->len > 0) { + if (list->name) { + printf("%s options:\n", list->name); + } else { + printf("Options:\n"); + } + } else if (array->len == 0) { + if (list->name) { + printf("There are no options for %s.\n", list->name); + } else { + printf("No options available.\n"); + } + } for (i = 0; i < array->len; i++) { printf("%s\n", (char *)array->pdata[i]); } @@ -XXX,XX +XXX,XX @@ QemuOpts *qemu_opts_parse_noisily(QemuOptsList *list, const char *params, opts = opts_parse(list, params, permit_abbrev, false, &invalidp, &err); if (err) { if (invalidp && has_help_option(params)) { - qemu_opts_print_help(list); + qemu_opts_print_help(list, true); error_free(err); } else { error_report_err(err); diff --git a/tests/qemu-iotests/082.out b/tests/qemu-iotests/082.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/082.out +++ b/tests/qemu-iotests/082.out @@ -XXX,XX +XXX,XX @@ cluster_size: 8192 Testing: create -f qcow2 -o help TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o ? TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2 128M Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -f qcow2 -u -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 128M Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2,,help cluster_size=65536 lazy_refcounts=off refcount_bits=16 @@ -XXX,XX +XXX,XX @@ qemu-img: Invalid option list: ,, Testing: create -f qcow2 -o help Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: create -o help Supported options: -size Virtual disk size + size=<size> - Virtual disk size Testing: create -f bochs -o help qemu-img: Format driver 'bochs' does not support image creation @@ -XXX,XX +XXX,XX @@ cluster_size: 8192 Testing: convert -O qcow2 -o help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o ? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits -nocow Turn off copy-on-write (valid only on btrfs) + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + nocow=<bool (on/off)> - Turn off copy-on-write (valid only on btrfs) + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -O qcow2 -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base qemu-img: Could not open 'TEST_DIR/t.qcow2.base': Could not open backing file: Could not open 'TEST_DIR/t.qcow2,help': No such file or directory @@ -XXX,XX +XXX,XX @@ qemu-img: Invalid option list: ,, Testing: convert -O qcow2 -o help Supported options: -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Testing: convert -o help Supported options: -size Virtual disk size + size=<size> - Virtual disk size Testing: convert -O bochs -o help qemu-img: Format driver 'bochs' does not support image creation @@ -XXX,XX +XXX,XX @@ cluster_size: 65536 Testing: amend -f qcow2 -o help TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o ? TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o cluster_size=4k,help TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o cluster_size=4k,? TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o help,cluster_size=4k TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o ?,cluster_size=4k TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o cluster_size=4k -o help TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: amend -f qcow2 -o cluster_size=4k -o ? TEST_DIR/t.qcow2 Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. @@ -XXX,XX +XXX,XX @@ qemu-img: Invalid option list: ,, Testing: amend -f qcow2 -o help Creation options for 'qcow2': -size Virtual disk size -compat Compatibility level (0.10 or 1.1) -backing_file File name of a base image -backing_fmt Image format of the base image -encryption Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) -encrypt.format Encrypt the image, format choices: 'aes', 'luks' -encrypt.key-secret ID of secret providing qcow AES key or LUKS passphrase -encrypt.cipher-alg Name of encryption cipher algorithm -encrypt.cipher-mode Name of encryption cipher mode -encrypt.ivgen-alg Name of IV generator algorithm -encrypt.ivgen-hash-alg Name of IV generator hash algorithm -encrypt.hash-alg Name of encryption hash algorithm -encrypt.iter-time Time to spend in PBKDF in milliseconds -cluster_size qcow2 cluster size -preallocation Preallocation mode (allowed values: off, metadata, falloc, full) -lazy_refcounts Postpone refcount updates -refcount_bits Width of a reference count entry in bits + backing_file=<str> - File name of a base image + backing_fmt=<str> - Image format of the base image + cluster_size=<size> - qcow2 cluster size + compat=<str> - Compatibility level (0.10 or 1.1) + encrypt.cipher-alg=<str> - Name of encryption cipher algorithm + encrypt.cipher-mode=<str> - Name of encryption cipher mode + encrypt.format=<str> - Encrypt the image, format choices: 'aes', 'luks' + encrypt.hash-alg=<str> - Name of encryption hash algorithm + encrypt.iter-time=<num> - Time to spend in PBKDF in milliseconds + encrypt.ivgen-alg=<str> - Name of IV generator algorithm + encrypt.ivgen-hash-alg=<str> - Name of IV generator hash algorithm + encrypt.key-secret=<str> - ID of secret providing qcow AES key or LUKS passphrase + encryption=<bool (on/off)> - Encrypt the image with format 'aes'. (Deprecated in favor of encrypt.format=aes) + lazy_refcounts=<bool (on/off)> - Postpone refcount updates + preallocation=<str> - Preallocation mode (allowed values: off, metadata, falloc, full) + refcount_bits=<num> - Width of a reference count entry in bits + size=<size> - Virtual disk size Note that not all of these options may be amendable. Testing: convert -o help Supported options: -size Virtual disk size + size=<size> - Virtual disk size Testing: amend -f bochs -o help qemu-img: Format driver 'bochs' does not support option amendment -- 2.19.1 From: Max Reitz <mreitz@redhat.com> Following the example of qemu_opts_print_help(), indent all entries in the list of character devices. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- chardev/char.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/chardev/char.c b/chardev/char.c index XXXXXXX..XXXXXXX 100644 --- a/chardev/char.c +++ b/chardev/char.c @@ -XXX,XX +XXX,XX @@ help_string_append(const char *name, void *opaque) { GString *str = opaque; - g_string_append_printf(str, "\n%s", name); + g_string_append_printf(str, "\n %s", name); } static const char *chardev_alias_translate(const char *name) -- 2.19.1 From: Max Reitz <mreitz@redhat.com> Just like in qemu_opts_print_help(), print the device name as a caption instead of on every single line, indent all options, add angle brackets around types, and align the descriptions after 24 characters. Also, separate the descriptions with " - " instead of putting them in parentheses, because that is what we do everywhere else. This does look a bit funny here because basically all bits have the description "on/off", but funny does not mean it is less readable. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- qdev-monitor.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/qdev-monitor.c b/qdev-monitor.c index XXXXXXX..XXXXXXX 100644 --- a/qdev-monitor.c +++ b/qdev-monitor.c @@ -XXX,XX +XXX,XX @@ int qdev_device_help(QemuOpts *opts) goto error; } + if (prop_list) { + out_printf("%s options:\n", driver); + } else { + out_printf("There are no options for %s.\n", driver); + } for (prop = prop_list; prop; prop = prop->next) { - out_printf("%s.%s=%s", driver, prop->value->name, prop->value->type); + int len; + out_printf(" %s=<%s>%n", prop->value->name, prop->value->type, &len); if (prop->value->has_description) { - out_printf(" (%s)\n", prop->value->description); + if (len < 24) { + out_printf("%*s", 24 - len, ""); + } + out_printf(" - %s\n", prop->value->description); } else { out_printf("\n"); } -- 2.19.1 From: Max Reitz <mreitz@redhat.com> Just like in qemu_opts_print_help(), print the object name as a caption instead of on every single line, indent all options, add angle brackets around types, and align the descriptions after 24 characters. Also, indent every object name in the list of available objects. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- vl.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/vl.c b/vl.c index XXXXXXX..XXXXXXX 100644 --- a/vl.c +++ b/vl.c @@ -XXX,XX +XXX,XX @@ static bool object_create_initial(const char *type, QemuOpts *opts) list = object_class_get_list_sorted(TYPE_USER_CREATABLE, false); for (l = list; l != NULL; l = l->next) { ObjectClass *oc = OBJECT_CLASS(l->data); - printf("%s\n", object_class_get_name(oc)); + printf(" %s\n", object_class_get_name(oc)); } g_slist_free(list); exit(0); @@ -XXX,XX +XXX,XX @@ static bool object_create_initial(const char *type, QemuOpts *opts) } str = g_string_new(NULL); - g_string_append_printf(str, "%s.%s=%s", type, - prop->name, prop->type); + g_string_append_printf(str, " %s=<%s>", prop->name, prop->type); if (prop->description) { + if (str->len < 24) { + g_string_append_printf(str, "%*s", 24 - (int)str->len, ""); + } g_string_append_printf(str, " - %s", prop->description); } g_ptr_array_add(array, g_string_free(str, false)); } g_ptr_array_sort(array, (GCompareFunc)qemu_pstrcmp0); + if (array->len > 0) { + printf("%s options:\n", type); + } else { + printf("There are no options for %s.\n", type); + } for (i = 0; i < array->len; i++) { printf("%s\n", (char *)array->pdata[i]); } -- 2.19.1 From: Max Reitz <mreitz@redhat.com> There is no good reason why there should be a newline in this description, so remove it. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- vl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/vl.c b/vl.c index XXXXXXX..XXXXXXX 100644 --- a/vl.c +++ b/vl.c @@ -XXX,XX +XXX,XX @@ static QemuOptsList qemu_fw_cfg_opts = { }, { .name = "file", .type = QEMU_OPT_STRING, - .help = "Sets the name of the file from which\n" + .help = "Sets the name of the file from which " "the fw_cfg blob will be loaded", }, { .name = "string", -- 2.19.1 From: Leonid Bloch <lbloch@janustech.com> If an expression is used to define DEFAULT_CLUSTER_SIZE, when compiled, it will be embedded as a literal expression in the binary (as the default value) because it is stringified to mark the size of the default value. Now this is fixed by using a defined number to define this value. Signed-off-by: Leonid Bloch <lbloch@janustech.com> Reviewed-by: Stefan Weil <sw@weilnetz.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vdi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/vdi.c b/block/vdi.c index XXXXXXX..XXXXXXX 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -XXX,XX +XXX,XX @@ #define BLOCK_OPT_STATIC "static" #define SECTOR_SIZE 512 -#define DEFAULT_CLUSTER_SIZE (1 * MiB) +#define DEFAULT_CLUSTER_SIZE S_1MiB #if defined(CONFIG_VDI_DEBUG) #define VDI_DEBUG 1 @@ -XXX,XX +XXX,XX @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } else if (header.block_size != DEFAULT_CLUSTER_SIZE) { error_setg(errp, "unsupported VDI image (block size %" PRIu32 - " is not %" PRIu64 ")", + " is not %" PRIu32 ")", header.block_size, DEFAULT_CLUSTER_SIZE); ret = -ENOTSUP; goto fail; -- 2.19.1 From: Leonid Bloch <lbloch@janustech.com> The lookup table for power-of-two sizes was added in commit 540b8492618eb for the purpose of having convenient shortcuts for these sizes in cases when the literal number has to be present at compile time, and expressions as '(1 * KiB)' can not be used. One such case is the stringification of sizes. Beyond that, it is convenient to use these shortcuts for all power-of-two sizes, even if they don't have to be literal numbers. Despite its convenience, this table introduced 55 lines of "dumb" code, the purpose and origin of which are obscure without reading the message of the commit which introduced it. This patch fixes that by adding a comment to the code itself with a brief explanation for the reasoning behind this table. This comment includes the short AWK script that generated the table, so that anyone who's interested could make sure that the values in it are correct (otherwise these values look as if they were typed manually). Signed-off-by: Leonid Bloch <lbloch@janustech.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/qemu/units.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/include/qemu/units.h b/include/qemu/units.h index XXXXXXX..XXXXXXX 100644 --- a/include/qemu/units.h +++ b/include/qemu/units.h @@ -XXX,XX +XXX,XX @@ #define PiB (INT64_C(1) << 50) #define EiB (INT64_C(1) << 60) +/* + * The following lookup table is intended to be used when a literal string of + * the number of bytes is required (for example if it needs to be stringified). + * It can also be used for generic shortcuts of power-of-two sizes. + * This table is generated using the AWK script below: + * + * BEGIN { + * suffix="KMGTPE"; + * for(i=10; i<64; i++) { + * val=2**i; + * s=substr(suffix, int(i/10), 1); + * n=2**(i%10); + * pad=21-int(log(n)/log(10)); + * printf("#define S_%d%siB %*d\n", n, s, pad, val); + * } + * } + */ + #define S_1KiB 1024 #define S_2KiB 2048 #define S_4KiB 4096 -- 2.19.1 The following changes since commit 5204b499a6cae4dfd9fe762d5e6e82224892383b: mailmap: Fix Stefan Weil author email (2022-12-13 15:56:57 -0500) are available in the Git repository at: https://repo.or.cz/qemu/kevin.git tags/for-upstream for you to fetch changes up to 2ad19e5dc950d4b340894846b9e71c0b20f9a1cc: block: GRAPH_RDLOCK for functions only called by co_wrappers (2022-12-14 13:13:07 +0100) ---------------------------------------------------------------- Block layer patches - Code cleanups around block graph modification - Simplify drain - coroutine_fn correctness fixes, including splitting generated coroutine wrappers into co_wrapper (to be called only from non-coroutine context) and co_wrapper_mixed (both coroutine and non-coroutine context) - Introduce a block graph rwlock ---------------------------------------------------------------- Emanuele Giuseppe Esposito (21): block-io: introduce coroutine_fn duplicates for bdrv_common_block_status_above callers block-copy: add coroutine_fn annotations nbd/server.c: add coroutine_fn annotations block-backend: replace bdrv_*_above with blk_*_above block/vmdk: add coroutine_fn annotations block: avoid duplicating filename string in bdrv_create block: distinguish between bdrv_create running in coroutine and not block: bdrv_create_file is a coroutine_fn block: rename generated_co_wrapper in co_wrapper_mixed block-coroutine-wrapper.py: introduce co_wrapper block-coroutine-wrapper.py: support functions without bs arg block-coroutine-wrapper.py: support also basic return types block: convert bdrv_create to co_wrapper block/dirty-bitmap: convert coroutine-only functions to co_wrapper graph-lock: Implement guard macros async: Register/unregister aiocontext in graph lock list block: wrlock in bdrv_replace_child_noperm block: remove unnecessary assert_bdrv_graph_writable() block: assert that graph read and writes are performed correctly block-coroutine-wrapper.py: introduce annotations that take the graph rdlock block: use co_wrapper_mixed_bdrv_rdlock in functions taking the rdlock Kevin Wolf (25): qed: Don't yield in bdrv_qed_co_drain_begin() test-bdrv-drain: Don't yield in .bdrv_co_drained_begin/end() block: Revert .bdrv_drained_begin/end to non-coroutine_fn block: Remove drained_end_counter block: Inline bdrv_drain_invoke() block: Fix locking for bdrv_reopen_queue_child() block: Drain individual nodes during reopen block: Don't use subtree drains in bdrv_drop_intermediate() stream: Replace subtree drain with a single node drain block: Remove subtree drains block: Call drain callbacks only once block: Remove ignore_bds_parents parameter from drain_begin/end. block: Drop out of coroutine in bdrv_do_drained_begin_quiesce() block: Don't poll in bdrv_replace_child_noperm() block: Remove poll parameter from bdrv_parent_drained_begin_single() block: Factor out bdrv_drain_all_begin_nopoll() Import clang-tsa.h clang-tsa: Add TSA_ASSERT() macro clang-tsa: Add macros for shared locks configure: Enable -Wthread-safety if present test-bdrv-drain: Fix incorrrect drain assumptions block: Fix locking in external_snapshot_prepare() graph-lock: TSA annotations for lock/unlock functions Mark assert_bdrv_graph_readable/writable() GRAPH_RD/WRLOCK block: GRAPH_RDLOCK for functions only called by co_wrappers Paolo Bonzini (1): graph-lock: Introduce a lock to protect block graph operations Vladimir Sementsov-Ogievskiy (4): block: Inline bdrv_detach_child() block: drop bdrv_remove_filter_or_cow_child block: bdrv_refresh_perms(): allow external tran block: refactor bdrv_list_refresh_perms to allow any list of nodes docs/devel/block-coroutine-wrapper.rst | 6 +- configure | 1 + block/block-gen.h | 11 +- block/coroutines.h | 21 +- include/block/aio.h | 9 + include/block/block-common.h | 27 ++- include/block/block-copy.h | 5 +- include/block/block-global-state.h | 15 +- include/block/block-io.h | 136 +++++------ include/block/block_int-common.h | 49 ++-- include/block/block_int-global-state.h | 17 -- include/block/block_int-io.h | 12 - include/block/block_int.h | 1 + include/block/dirty-bitmap.h | 10 +- include/block/graph-lock.h | 280 +++++++++++++++++++++++ include/qemu/clang-tsa.h | 114 ++++++++++ include/sysemu/block-backend-io.h | 77 ++++--- block.c | 404 ++++++++++++++++++--------------- block/block-backend.c | 25 +- block/block-copy.c | 21 +- block/commit.c | 4 +- block/crypto.c | 2 +- block/dirty-bitmap.c | 88 +------ block/graph-lock.c | 275 ++++++++++++++++++++++ block/io.c | 367 ++++++++++-------------------- block/parallels.c | 2 +- block/qcow.c | 2 +- block/qcow2.c | 4 +- block/qed.c | 28 ++- block/raw-format.c | 2 +- block/replication.c | 6 - block/stream.c | 26 ++- block/throttle.c | 8 +- block/vdi.c | 2 +- block/vhdx.c | 2 +- block/vmdk.c | 38 ++-- block/vpc.c | 2 +- blockdev.c | 17 +- blockjob.c | 2 +- nbd/server.c | 47 ++-- stubs/graph-lock.c | 10 + tests/unit/test-bdrv-drain.c | 387 +++++++++---------------------- util/async.c | 4 + scripts/block-coroutine-wrapper.py | 133 ++++++++--- block/meson.build | 2 + stubs/meson.build | 1 + 46 files changed, 1575 insertions(+), 1127 deletions(-) create mode 100644 include/block/graph-lock.h create mode 100644 include/qemu/clang-tsa.h create mode 100644 block/graph-lock.c create mode 100644 stubs/graph-lock.c From: Vladimir Sementsov-Ogievskiy <vladimir.sementsov-ogievskiy@openvz.org> The only caller is bdrv_root_unref_child(), let's just do the logic directly in it. It simplifies further conversion of bdrv_root_unref_child() to transaction actions. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107163558.618889-2-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 46 +++++++++++++++++++--------------------------- 1 file changed, 19 insertions(+), 27 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static BdrvChild *bdrv_attach_child_noperm(BlockDriverState *parent_bs, tran, errp); } -static void bdrv_detach_child(BdrvChild *child) -{ - BlockDriverState *old_bs = child->bs; - - GLOBAL_STATE_CODE(); - bdrv_replace_child_noperm(child, NULL); - bdrv_child_free(child); - - if (old_bs) { - /* - * Update permissions for old node. We're just taking a parent away, so - * we're loosening restrictions. Errors of permission update are not - * fatal in this case, ignore them. - */ - bdrv_refresh_perms(old_bs, NULL); - - /* - * When the parent requiring a non-default AioContext is removed, the - * node moves back to the main AioContext - */ - bdrv_try_change_aio_context(old_bs, qemu_get_aio_context(), NULL, NULL); - } -} - /* * This function steals the reference to child_bs from the caller. * That reference is later dropped by bdrv_root_unref_child(). @@ -XXX,XX +XXX,XX @@ out: /* Callers must ensure that child->frozen is false. */ void bdrv_root_unref_child(BdrvChild *child) { - BlockDriverState *child_bs; + BlockDriverState *child_bs = child->bs; GLOBAL_STATE_CODE(); + bdrv_replace_child_noperm(child, NULL); + bdrv_child_free(child); + + if (child_bs) { + /* + * Update permissions for old node. We're just taking a parent away, so + * we're loosening restrictions. Errors of permission update are not + * fatal in this case, ignore them. + */ + bdrv_refresh_perms(child_bs, NULL); + + /* + * When the parent requiring a non-default AioContext is removed, the + * node moves back to the main AioContext + */ + bdrv_try_change_aio_context(child_bs, qemu_get_aio_context(), NULL, + NULL); + } - child_bs = child->bs; - bdrv_detach_child(child); bdrv_unref(child_bs); } -- 2.38.1 From: Vladimir Sementsov-Ogievskiy <vladimir.sementsov-ogievskiy@openvz.org> Drop this simple wrapper used only in one place. We have too many graph modifying functions even without it. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107163558.618889-3-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 15 +-------------- 1 file changed, 1 insertion(+), 14 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static bool bdrv_recurse_has_child(BlockDriverState *bs, static void bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs); static void bdrv_remove_child(BdrvChild *child, Transaction *tran); -static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs, - Transaction *tran); static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, @@ -XXX,XX +XXX,XX @@ static void bdrv_remove_child(BdrvChild *child, Transaction *tran) tran_add(tran, &bdrv_remove_child_drv, child); } -/* - * A function to remove backing-chain child of @bs if exists: cow child for - * format nodes (always .backing) and filter child for filters (may be .file or - * .backing) - */ -static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs, - Transaction *tran) -{ - bdrv_remove_child(bdrv_filter_or_cow_child(bs), tran); -} - static int bdrv_replace_node_noperm(BlockDriverState *from, BlockDriverState *to, bool auto_skip, Transaction *tran, @@ -XXX,XX +XXX,XX @@ static int bdrv_replace_node_common(BlockDriverState *from, } if (detach_subchain) { - bdrv_remove_filter_or_cow_child(to_cow_parent, tran); + bdrv_remove_child(bdrv_filter_or_cow_child(to_cow_parent), tran); } found = g_hash_table_new(NULL, NULL); -- 2.38.1 From: Vladimir Sementsov-Ogievskiy <vladimir.sementsov-ogievskiy@openvz.org> Allow passing external Transaction pointer, stop creating extra Transaction objects. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107163558.618889-4-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ char *bdrv_perm_names(uint64_t perm) } -static int bdrv_refresh_perms(BlockDriverState *bs, Error **errp) +/* @tran is allowed to be NULL. In this case no rollback is possible */ +static int bdrv_refresh_perms(BlockDriverState *bs, Transaction *tran, + Error **errp) { int ret; - Transaction *tran = tran_new(); + Transaction *local_tran = NULL; g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); GLOBAL_STATE_CODE(); + if (!tran) { + tran = local_tran = tran_new(); + } + ret = bdrv_list_refresh_perms(list, NULL, tran, errp); - tran_finalize(tran, ret); + + if (local_tran) { + tran_finalize(local_tran, ret); + } return ret; } @@ -XXX,XX +XXX,XX @@ int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, bdrv_child_set_perm(c, perm, shared, tran); - ret = bdrv_refresh_perms(c->bs, &local_err); + ret = bdrv_refresh_perms(c->bs, tran, &local_err); tran_finalize(tran, ret); @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, goto out; } - ret = bdrv_refresh_perms(child_bs, errp); + ret = bdrv_refresh_perms(child_bs, tran, errp); out: tran_finalize(tran, ret); @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, goto out; } - ret = bdrv_refresh_perms(parent_bs, errp); + ret = bdrv_refresh_perms(parent_bs, tran, errp); if (ret < 0) { goto out; } @@ -XXX,XX +XXX,XX @@ void bdrv_root_unref_child(BdrvChild *child) * we're loosening restrictions. Errors of permission update are not * fatal in this case, ignore them. */ - bdrv_refresh_perms(child_bs, NULL); + bdrv_refresh_perms(child_bs, NULL, NULL); /* * When the parent requiring a non-default AioContext is removed, the @@ -XXX,XX +XXX,XX @@ int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, goto out; } - ret = bdrv_refresh_perms(bs, errp); + ret = bdrv_refresh_perms(bs, tran, errp); out: tran_finalize(tran, ret); @@ -XXX,XX +XXX,XX @@ int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, goto out; } - ret = bdrv_refresh_perms(bs_new, errp); + ret = bdrv_refresh_perms(bs_new, tran, errp); out: tran_finalize(tran, ret); @@ -XXX,XX +XXX,XX @@ int bdrv_activate(BlockDriverState *bs, Error **errp) */ if (bs->open_flags & BDRV_O_INACTIVE) { bs->open_flags &= ~BDRV_O_INACTIVE; - ret = bdrv_refresh_perms(bs, errp); + ret = bdrv_refresh_perms(bs, NULL, errp); if (ret < 0) { bs->open_flags |= BDRV_O_INACTIVE; return ret; @@ -XXX,XX +XXX,XX @@ static int bdrv_inactivate_recurse(BlockDriverState *bs) * We only tried to loosen restrictions, so errors are not fatal, ignore * them. */ - bdrv_refresh_perms(bs, NULL); + bdrv_refresh_perms(bs, NULL, NULL); /* Recursively inactivate children */ QLIST_FOREACH(child, &bs->children, next) { -- 2.38.1 From: Vladimir Sementsov-Ogievskiy <vladimir.sementsov-ogievskiy@openvz.org> We are going to increase usage of collecting nodes in a list to then update, and calling bdrv_topological_dfs() each time is not convenient, and not correct as we are going to interleave graph modifying with filling the node list. So, let's switch to a function that takes any list of nodes, adds all their subtrees and do topological sort. And finally, refresh permissions. While being here, make the function public, as we'll want to use it from blockdev.c in near future. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107163558.618889-5-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 51 ++++++++++++++++++++++++++++++++------------------- 1 file changed, 32 insertions(+), 19 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static int bdrv_node_refresh_perm(BlockDriverState *bs, BlockReopenQueue *q, return 0; } -static int bdrv_list_refresh_perms(GSList *list, BlockReopenQueue *q, - Transaction *tran, Error **errp) +/* + * @list is a product of bdrv_topological_dfs() (may be called several times) - + * a topologically sorted subgraph. + */ +static int bdrv_do_refresh_perms(GSList *list, BlockReopenQueue *q, + Transaction *tran, Error **errp) { int ret; BlockDriverState *bs; @@ -XXX,XX +XXX,XX @@ static int bdrv_list_refresh_perms(GSList *list, BlockReopenQueue *q, return 0; } +/* + * @list is any list of nodes. List is completed by all subtrees and + * topologically sorted. It's not a problem if some node occurs in the @list + * several times. + */ +static int bdrv_list_refresh_perms(GSList *list, BlockReopenQueue *q, + Transaction *tran, Error **errp) +{ + g_autoptr(GHashTable) found = g_hash_table_new(NULL, NULL); + g_autoptr(GSList) refresh_list = NULL; + + for ( ; list; list = list->next) { + refresh_list = bdrv_topological_dfs(refresh_list, found, list->data); + } + + return bdrv_do_refresh_perms(refresh_list, q, tran, errp); +} + void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, uint64_t *shared_perm) { @@ -XXX,XX +XXX,XX @@ static int bdrv_refresh_perms(BlockDriverState *bs, Transaction *tran, tran = local_tran = tran_new(); } - ret = bdrv_list_refresh_perms(list, NULL, tran, errp); + ret = bdrv_do_refresh_perms(list, NULL, tran, errp); if (local_tran) { tran_finalize(local_tran, ret); @@ -XXX,XX +XXX,XX @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) BlockReopenQueueEntry *bs_entry, *next; AioContext *ctx; Transaction *tran = tran_new(); - g_autoptr(GHashTable) found = NULL; g_autoptr(GSList) refresh_list = NULL; assert(qemu_get_current_aio_context() == qemu_get_aio_context()); @@ -XXX,XX +XXX,XX @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) bs_entry->prepared = true; } - found = g_hash_table_new(NULL, NULL); QTAILQ_FOREACH(bs_entry, bs_queue, entry) { BDRVReopenState *state = &bs_entry->state; - refresh_list = bdrv_topological_dfs(refresh_list, found, state->bs); + refresh_list = g_slist_prepend(refresh_list, state->bs); if (state->old_backing_bs) { - refresh_list = bdrv_topological_dfs(refresh_list, found, - state->old_backing_bs); + refresh_list = g_slist_prepend(refresh_list, state->old_backing_bs); } if (state->old_file_bs) { - refresh_list = bdrv_topological_dfs(refresh_list, found, - state->old_file_bs); + refresh_list = g_slist_prepend(refresh_list, state->old_file_bs); } } @@ -XXX,XX +XXX,XX @@ static int bdrv_replace_node_common(BlockDriverState *from, Error **errp) { Transaction *tran = tran_new(); - g_autoptr(GHashTable) found = NULL; g_autoptr(GSList) refresh_list = NULL; BlockDriverState *to_cow_parent = NULL; int ret; @@ -XXX,XX +XXX,XX @@ static int bdrv_replace_node_common(BlockDriverState *from, bdrv_remove_child(bdrv_filter_or_cow_child(to_cow_parent), tran); } - found = g_hash_table_new(NULL, NULL); - - refresh_list = bdrv_topological_dfs(refresh_list, found, to); - refresh_list = bdrv_topological_dfs(refresh_list, found, from); + refresh_list = g_slist_prepend(refresh_list, to); + refresh_list = g_slist_prepend(refresh_list, from); ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, { int ret; Transaction *tran = tran_new(); - g_autoptr(GHashTable) found = NULL; g_autoptr(GSList) refresh_list = NULL; BlockDriverState *old_bs = child->bs; @@ -XXX,XX +XXX,XX @@ int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, bdrv_replace_child_tran(child, new_bs, tran); - found = g_hash_table_new(NULL, NULL); - refresh_list = bdrv_topological_dfs(refresh_list, found, old_bs); - refresh_list = bdrv_topological_dfs(refresh_list, found, new_bs); + refresh_list = g_slist_prepend(refresh_list, old_bs); + refresh_list = g_slist_prepend(refresh_list, new_bs); ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); -- 2.38.1 We want to change .bdrv_co_drained_begin() back to be a non-coroutine callback, so in preparation, avoid yielding in its implementation. Because we increase bs->in_flight and bdrv_drained_begin() polls, the behaviour is unchanged. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-2-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qed.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/block/qed.c b/block/qed.c index XXXXXXX..XXXXXXX 100644 --- a/block/qed.c +++ b/block/qed.c @@ -XXX,XX +XXX,XX @@ static void coroutine_fn qed_unplug_allocating_write_reqs(BDRVQEDState *s) qemu_co_mutex_unlock(&s->table_lock); } -static void coroutine_fn qed_need_check_timer_entry(void *opaque) +static void coroutine_fn qed_need_check_timer(BDRVQEDState *s) { - BDRVQEDState *s = opaque; int ret; trace_qed_need_check_timer_cb(s); @@ -XXX,XX +XXX,XX @@ static void coroutine_fn qed_need_check_timer_entry(void *opaque) (void) ret; } +static void coroutine_fn qed_need_check_timer_entry(void *opaque) +{ + BDRVQEDState *s = opaque; + + qed_need_check_timer(opaque); + bdrv_dec_in_flight(s->bs); +} + static void qed_need_check_timer_cb(void *opaque) { + BDRVQEDState *s = opaque; Coroutine *co = qemu_coroutine_create(qed_need_check_timer_entry, opaque); + + bdrv_inc_in_flight(s->bs); qemu_coroutine_enter(co); } @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_qed_co_drain_begin(BlockDriverState *bs) * header is flushed. */ if (s->need_check_timer && timer_pending(s->need_check_timer)) { + Coroutine *co; + qed_cancel_need_check_timer(s); - qed_need_check_timer_entry(s); + co = qemu_coroutine_create(qed_need_check_timer_entry, s); + bdrv_inc_in_flight(bs); + aio_co_enter(bdrv_get_aio_context(bs), co); } } -- 2.38.1 We want to change .bdrv_co_drained_begin/end() back to be non-coroutine callbacks, so in preparation, avoid yielding in their implementation. This does almost the same as the existing logic in bdrv_drain_invoke(), by creating and entering coroutines internally. However, since the test case is by far the heaviest user of coroutine code in drain callbacks, it is preferable to have the complexity in the test case rather than the drain core, which is already complicated enough without this. The behaviour for bdrv_drain_begin() is unchanged because we increase bs->in_flight and this is still polled. However, bdrv_drain_end() doesn't wait for the spawned coroutine to complete any more. This is fine, we don't rely on bdrv_drain_end() restarting all operations immediately before the next aio_poll(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-3-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/unit/test-bdrv-drain.c | 64 ++++++++++++++++++++++++++---------- 1 file changed, 46 insertions(+), 18 deletions(-) diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ typedef struct BDRVTestState { bool sleep_in_drain_begin; } BDRVTestState; +static void coroutine_fn sleep_in_drain_begin(void *opaque) +{ + BlockDriverState *bs = opaque; + + qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000); + bdrv_dec_in_flight(bs); +} + static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs) { BDRVTestState *s = bs->opaque; s->drain_count++; if (s->sleep_in_drain_begin) { - qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000); + Coroutine *co = qemu_coroutine_create(sleep_in_drain_begin, bs); + bdrv_inc_in_flight(bs); + aio_co_enter(bdrv_get_aio_context(bs), co); } } @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_replace_test_co_preadv(BlockDriverState *bs, return 0; } +static void coroutine_fn bdrv_replace_test_drain_co(void *opaque) +{ + BlockDriverState *bs = opaque; + BDRVReplaceTestState *s = bs->opaque; + + /* Keep waking io_co up until it is done */ + while (s->io_co) { + aio_co_wake(s->io_co); + s->io_co = NULL; + qemu_coroutine_yield(); + } + s->drain_co = NULL; + bdrv_dec_in_flight(bs); +} + /** * If .drain_count is 0, wake up .io_co if there is one; and set * .was_drained. @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_replace_test_co_drain_begin(BlockDriverState *bs) BDRVReplaceTestState *s = bs->opaque; if (!s->drain_count) { - /* Keep waking io_co up until it is done */ - s->drain_co = qemu_coroutine_self(); - while (s->io_co) { - aio_co_wake(s->io_co); - s->io_co = NULL; - qemu_coroutine_yield(); - } - s->drain_co = NULL; - + s->drain_co = qemu_coroutine_create(bdrv_replace_test_drain_co, bs); + bdrv_inc_in_flight(bs); + aio_co_enter(bdrv_get_aio_context(bs), s->drain_co); s->was_drained = true; } s->drain_count++; } +static void coroutine_fn bdrv_replace_test_read_entry(void *opaque) +{ + BlockDriverState *bs = opaque; + char data; + QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1); + int ret; + + /* Queue a read request post-drain */ + ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0); + g_assert(ret >= 0); + bdrv_dec_in_flight(bs); +} + /** * Reduce .drain_count, set .was_undrained once it reaches 0. * If .drain_count reaches 0 and the node has a backing file, issue a @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_replace_test_co_drain_end(BlockDriverState *bs) g_assert(s->drain_count > 0); if (!--s->drain_count) { - int ret; - s->was_undrained = true; if (bs->backing) { - char data; - QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1); - - /* Queue a read request post-drain */ - ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0); - g_assert(ret >= 0); + Coroutine *co = qemu_coroutine_create(bdrv_replace_test_read_entry, + bs); + bdrv_inc_in_flight(bs); + aio_co_enter(bdrv_get_aio_context(bs), co); } } } -- 2.38.1 Polling during bdrv_drained_end() can be problematic (and in the future, we may get cases for bdrv_drained_begin() where polling is forbidden, and we don't care about already in-flight requests, but just want to prevent new requests from arriving). The .bdrv_drained_begin/end callbacks running in a coroutine is the only reason why we have to do this polling, so make them non-coroutine callbacks again. None of the callers actually yield any more. This means that bdrv_drained_end() effectively doesn't poll any more, even if AIO_WAIT_WHILE() loops are still there (their condition is false from the beginning). This is generally not a problem, but in test-bdrv-drain, some additional explicit aio_poll() calls need to be added because the test case wants to verify the final state after BHs have executed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-4-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block_int-common.h | 10 ++++--- block.c | 4 +-- block/io.c | 49 +++++--------------------------- block/qed.c | 6 ++-- block/throttle.c | 8 +++--- tests/unit/test-bdrv-drain.c | 18 ++++++------ 6 files changed, 32 insertions(+), 63 deletions(-) diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BlockDriver { void (*bdrv_io_unplug)(BlockDriverState *bs); /** - * bdrv_co_drain_begin is called if implemented in the beginning of a + * bdrv_drain_begin is called if implemented in the beginning of a * drain operation to drain and stop any internal sources of requests in * the driver. - * bdrv_co_drain_end is called if implemented at the end of the drain. + * bdrv_drain_end is called if implemented at the end of the drain. * * They should be used by the driver to e.g. manage scheduled I/O * requests, or toggle an internal state. After the end of the drain new * requests will continue normally. + * + * Implementations of both functions must not call aio_poll(). */ - void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs); - void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs); + void (*bdrv_drain_begin)(BlockDriverState *bs); + void (*bdrv_drain_end)(BlockDriverState *bs); bool (*bdrv_supports_persistent_dirty_bitmap)(BlockDriverState *bs); bool coroutine_fn (*bdrv_co_can_store_new_dirty_bitmap)( diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static int bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv, assert(is_power_of_2(bs->bl.request_alignment)); for (i = 0; i < bs->quiesce_counter; i++) { - if (drv->bdrv_co_drain_begin) { - drv->bdrv_co_drain_begin(bs); + if (drv->bdrv_drain_begin) { + drv->bdrv_drain_begin(bs); } } diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ typedef struct { int *drained_end_counter; } BdrvCoDrainData; -static void coroutine_fn bdrv_drain_invoke_entry(void *opaque) -{ - BdrvCoDrainData *data = opaque; - BlockDriverState *bs = data->bs; - - if (data->begin) { - bs->drv->bdrv_co_drain_begin(bs); - } else { - bs->drv->bdrv_co_drain_end(bs); - } - - /* Set data->done and decrement drained_end_counter before bdrv_wakeup() */ - qatomic_mb_set(&data->done, true); - if (!data->begin) { - qatomic_dec(data->drained_end_counter); - } - bdrv_dec_in_flight(bs); - - g_free(data); -} - -/* Recursively call BlockDriver.bdrv_co_drain_begin/end callbacks */ +/* Recursively call BlockDriver.bdrv_drain_begin/end callbacks */ static void bdrv_drain_invoke(BlockDriverState *bs, bool begin, int *drained_end_counter) { - BdrvCoDrainData *data; - - if (!bs->drv || (begin && !bs->drv->bdrv_co_drain_begin) || - (!begin && !bs->drv->bdrv_co_drain_end)) { + if (!bs->drv || (begin && !bs->drv->bdrv_drain_begin) || + (!begin && !bs->drv->bdrv_drain_end)) { return; } - data = g_new(BdrvCoDrainData, 1); - *data = (BdrvCoDrainData) { - .bs = bs, - .done = false, - .begin = begin, - .drained_end_counter = drained_end_counter, - }; - - if (!begin) { - qatomic_inc(drained_end_counter); + if (begin) { + bs->drv->bdrv_drain_begin(bs); + } else { + bs->drv->bdrv_drain_end(bs); } - - /* Make sure the driver callback completes during the polling phase for - * drain_begin. */ - bdrv_inc_in_flight(bs); - data->co = qemu_coroutine_create(bdrv_drain_invoke_entry, data); - aio_co_schedule(bdrv_get_aio_context(bs), data->co); } /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */ diff --git a/block/qed.c b/block/qed.c index XXXXXXX..XXXXXXX 100644 --- a/block/qed.c +++ b/block/qed.c @@ -XXX,XX +XXX,XX @@ static bool coroutine_fn qed_plug_allocating_write_reqs(BDRVQEDState *s) assert(!s->allocating_write_reqs_plugged); if (s->allocating_acb != NULL) { /* Another allocating write came concurrently. This cannot happen - * from bdrv_qed_co_drain_begin, but it can happen when the timer runs. + * from bdrv_qed_drain_begin, but it can happen when the timer runs. */ qemu_co_mutex_unlock(&s->table_lock); return false; @@ -XXX,XX +XXX,XX @@ static void bdrv_qed_attach_aio_context(BlockDriverState *bs, } } -static void coroutine_fn bdrv_qed_co_drain_begin(BlockDriverState *bs) +static void bdrv_qed_drain_begin(BlockDriverState *bs) { BDRVQEDState *s = bs->opaque; @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_qed = { .bdrv_co_check = bdrv_qed_co_check, .bdrv_detach_aio_context = bdrv_qed_detach_aio_context, .bdrv_attach_aio_context = bdrv_qed_attach_aio_context, - .bdrv_co_drain_begin = bdrv_qed_co_drain_begin, + .bdrv_drain_begin = bdrv_qed_drain_begin, }; static void bdrv_qed_init(void) diff --git a/block/throttle.c b/block/throttle.c index XXXXXXX..XXXXXXX 100644 --- a/block/throttle.c +++ b/block/throttle.c @@ -XXX,XX +XXX,XX @@ static void throttle_reopen_abort(BDRVReopenState *reopen_state) reopen_state->opaque = NULL; } -static void coroutine_fn throttle_co_drain_begin(BlockDriverState *bs) +static void throttle_drain_begin(BlockDriverState *bs) { ThrottleGroupMember *tgm = bs->opaque; if (qatomic_fetch_inc(&tgm->io_limits_disabled) == 0) { @@ -XXX,XX +XXX,XX @@ static void coroutine_fn throttle_co_drain_begin(BlockDriverState *bs) } } -static void coroutine_fn throttle_co_drain_end(BlockDriverState *bs) +static void throttle_drain_end(BlockDriverState *bs) { ThrottleGroupMember *tgm = bs->opaque; assert(tgm->io_limits_disabled); @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_throttle = { .bdrv_reopen_commit = throttle_reopen_commit, .bdrv_reopen_abort = throttle_reopen_abort, - .bdrv_co_drain_begin = throttle_co_drain_begin, - .bdrv_co_drain_end = throttle_co_drain_end, + .bdrv_drain_begin = throttle_drain_begin, + .bdrv_drain_end = throttle_drain_end, .is_filter = true, .strong_runtime_opts = throttle_strong_runtime_opts, diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ static void coroutine_fn sleep_in_drain_begin(void *opaque) bdrv_dec_in_flight(bs); } -static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs) +static void bdrv_test_drain_begin(BlockDriverState *bs) { BDRVTestState *s = bs->opaque; s->drain_count++; @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_test_co_drain_begin(BlockDriverState *bs) } } -static void coroutine_fn bdrv_test_co_drain_end(BlockDriverState *bs) +static void bdrv_test_drain_end(BlockDriverState *bs) { BDRVTestState *s = bs->opaque; s->drain_count--; @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_test = { .bdrv_close = bdrv_test_close, .bdrv_co_preadv = bdrv_test_co_preadv, - .bdrv_co_drain_begin = bdrv_test_co_drain_begin, - .bdrv_co_drain_end = bdrv_test_co_drain_end, + .bdrv_drain_begin = bdrv_test_drain_begin, + .bdrv_drain_end = bdrv_test_drain_end, .bdrv_child_perm = bdrv_default_perms, @@ -XXX,XX +XXX,XX @@ static void test_blockjob_commit_by_drained_end(void) bdrv_drained_begin(bs_child); g_assert(!job_has_completed); bdrv_drained_end(bs_child); + aio_poll(qemu_get_aio_context(), false); g_assert(job_has_completed); bdrv_unref(bs_parents[0]); @@ -XXX,XX +XXX,XX @@ static void test_drop_intermediate_poll(void) g_assert(!job_has_completed); ret = bdrv_drop_intermediate(chain[1], chain[0], NULL); + aio_poll(qemu_get_aio_context(), false); g_assert(ret == 0); g_assert(job_has_completed); @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_replace_test_drain_co(void *opaque) * .was_drained. * Increment .drain_count. */ -static void coroutine_fn bdrv_replace_test_co_drain_begin(BlockDriverState *bs) +static void bdrv_replace_test_drain_begin(BlockDriverState *bs) { BDRVReplaceTestState *s = bs->opaque; @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_replace_test_read_entry(void *opaque) * If .drain_count reaches 0 and the node has a backing file, issue a * read request. */ -static void coroutine_fn bdrv_replace_test_co_drain_end(BlockDriverState *bs) +static void bdrv_replace_test_drain_end(BlockDriverState *bs) { BDRVReplaceTestState *s = bs->opaque; @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_replace_test = { .bdrv_close = bdrv_replace_test_close, .bdrv_co_preadv = bdrv_replace_test_co_preadv, - .bdrv_co_drain_begin = bdrv_replace_test_co_drain_begin, - .bdrv_co_drain_end = bdrv_replace_test_co_drain_end, + .bdrv_drain_begin = bdrv_replace_test_drain_begin, + .bdrv_drain_end = bdrv_replace_test_drain_end, .bdrv_child_perm = bdrv_default_perms, }; -- 2.38.1 drained_end_counter is unused now, nobody changes its value any more. It can be removed. In cases where we had two almost identical functions that only differed in whether the caller passes drained_end_counter, or whether they would poll for a local drained_end_counter to reach 0, these become a single function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20221118174110.55183-5-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 24 -------- include/block/block_int-common.h | 6 +- block.c | 5 +- block/block-backend.c | 4 +- block/io.c | 98 ++++++++------------------------ blockjob.c | 2 +- 6 files changed, 30 insertions(+), 109 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_copy_range(BdrvChild *src, int64_t src_offset, int64_t bytes, BdrvRequestFlags read_flags, BdrvRequestFlags write_flags); -/** - * bdrv_drained_end_no_poll: - * - * Same as bdrv_drained_end(), but do not poll for the subgraph to - * actually become unquiesced. Therefore, no graph changes will occur - * with this function. - * - * *drained_end_counter is incremented for every background operation - * that is scheduled, and will be decremented for every operation once - * it settles. The caller must poll until it reaches 0. The counter - * should be accessed using atomic operations only. - */ -void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); - - /* * "I/O or GS" API functions. These functions can run without * the BQL, but only in one specific iothread/main loop. @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); * bdrv_parent_drained_end_single: * * End a quiesced section for the parent of @c. - * - * This polls @bs's AioContext until all scheduled sub-drained_ends - * have settled, which may result in graph changes. */ void bdrv_parent_drained_end_single(BdrvChild *c); @@ -XXX,XX +XXX,XX @@ void bdrv_subtree_drained_begin(BlockDriverState *bs); * bdrv_drained_end: * * End a quiescent section started by bdrv_drained_begin(). - * - * This polls @bs's AioContext until all scheduled sub-drained_ends - * have settled. On one hand, that may result in graph changes. On - * the other, this requires that the caller either runs in the main - * loop; or that all involved nodes (@bs and all of its parents) are - * in the caller's AioContext. */ void bdrv_drained_end(BlockDriverState *bs); diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BdrvChildClass { * These functions must not change the graph (and therefore also must not * call aio_poll(), which could change the graph indirectly). * - * If drained_end() schedules background operations, it must atomically - * increment *drained_end_counter for each such operation and atomically - * decrement it once the operation has settled. - * * Note that this can be nested. If drained_begin() was called twice, new * I/O is allowed only after drained_end() was called twice, too. */ void (*drained_begin)(BdrvChild *child); - void (*drained_end)(BdrvChild *child, int *drained_end_counter); + void (*drained_end)(BdrvChild *child); /* * Returns whether the parent has pending requests for the child. This diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static bool bdrv_child_cb_drained_poll(BdrvChild *child) return bdrv_drain_poll(bs, false, NULL, false); } -static void bdrv_child_cb_drained_end(BdrvChild *child, - int *drained_end_counter) +static void bdrv_child_cb_drained_end(BdrvChild *child) { BlockDriverState *bs = child->opaque; - bdrv_drained_end_no_poll(bs, drained_end_counter); + bdrv_drained_end(bs); } static int bdrv_child_cb_inactivate(BdrvChild *child) diff --git a/block/block-backend.c b/block/block-backend.c index XXXXXXX..XXXXXXX 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -XXX,XX +XXX,XX @@ static void blk_root_inherit_options(BdrvChildRole role, bool parent_is_format, } static void blk_root_drained_begin(BdrvChild *child); static bool blk_root_drained_poll(BdrvChild *child); -static void blk_root_drained_end(BdrvChild *child, int *drained_end_counter); +static void blk_root_drained_end(BdrvChild *child); static void blk_root_change_media(BdrvChild *child, bool load); static void blk_root_resize(BdrvChild *child); @@ -XXX,XX +XXX,XX @@ static bool blk_root_drained_poll(BdrvChild *child) return busy || !!blk->in_flight; } -static void blk_root_drained_end(BdrvChild *child, int *drained_end_counter) +static void blk_root_drained_end(BdrvChild *child) { BlockBackend *blk = child->opaque; assert(blk->quiesce_counter); diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore, } } -static void bdrv_parent_drained_end_single_no_poll(BdrvChild *c, - int *drained_end_counter) +void bdrv_parent_drained_end_single(BdrvChild *c) { + IO_OR_GS_CODE(); + assert(c->parent_quiesce_counter > 0); c->parent_quiesce_counter--; if (c->klass->drained_end) { - c->klass->drained_end(c, drained_end_counter); + c->klass->drained_end(c); } } -void bdrv_parent_drained_end_single(BdrvChild *c) -{ - int drained_end_counter = 0; - AioContext *ctx = bdrv_child_get_parent_aio_context(c); - IO_OR_GS_CODE(); - bdrv_parent_drained_end_single_no_poll(c, &drained_end_counter); - AIO_WAIT_WHILE(ctx, qatomic_read(&drained_end_counter) > 0); -} - static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore, - bool ignore_bds_parents, - int *drained_end_counter) + bool ignore_bds_parents) { BdrvChild *c; @@ -XXX,XX +XXX,XX @@ static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore, if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) { continue; } - bdrv_parent_drained_end_single_no_poll(c, drained_end_counter); + bdrv_parent_drained_end_single(c); } } @@ -XXX,XX +XXX,XX @@ typedef struct { bool poll; BdrvChild *parent; bool ignore_bds_parents; - int *drained_end_counter; } BdrvCoDrainData; /* Recursively call BlockDriver.bdrv_drain_begin/end callbacks */ -static void bdrv_drain_invoke(BlockDriverState *bs, bool begin, - int *drained_end_counter) +static void bdrv_drain_invoke(BlockDriverState *bs, bool begin) { if (!bs->drv || (begin && !bs->drv->bdrv_drain_begin) || (!begin && !bs->drv->bdrv_drain_end)) { @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, BdrvChild *parent, bool ignore_bds_parents, bool poll); static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents, - int *drained_end_counter); + BdrvChild *parent, bool ignore_bds_parents); static void bdrv_co_drain_bh_cb(void *opaque) { @@ -XXX,XX +XXX,XX @@ static void bdrv_co_drain_bh_cb(void *opaque) aio_context_acquire(ctx); bdrv_dec_in_flight(bs); if (data->begin) { - assert(!data->drained_end_counter); bdrv_do_drained_begin(bs, data->recursive, data->parent, data->ignore_bds_parents, data->poll); } else { assert(!data->poll); bdrv_do_drained_end(bs, data->recursive, data->parent, - data->ignore_bds_parents, - data->drained_end_counter); + data->ignore_bds_parents); } aio_context_release(ctx); } else { @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, bool begin, bool recursive, BdrvChild *parent, bool ignore_bds_parents, - bool poll, - int *drained_end_counter) + bool poll) { BdrvCoDrainData data; Coroutine *self = qemu_coroutine_self(); @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, .parent = parent, .ignore_bds_parents = ignore_bds_parents, .poll = poll, - .drained_end_counter = drained_end_counter, }; if (bs) { @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, } bdrv_parent_drained_begin(bs, parent, ignore_bds_parents); - bdrv_drain_invoke(bs, true, NULL); + bdrv_drain_invoke(bs, true); } static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, if (qemu_in_coroutine()) { bdrv_co_yield_to_drain(bs, true, recursive, parent, ignore_bds_parents, - poll, NULL); + poll); return; } @@ -XXX,XX +XXX,XX @@ void bdrv_subtree_drained_begin(BlockDriverState *bs) /** * This function does not poll, nor must any of its recursively called - * functions. The *drained_end_counter pointee will be incremented - * once for every background operation scheduled, and decremented once - * the operation settles. Therefore, the pointer must remain valid - * until the pointee reaches 0. That implies that whoever sets up the - * pointee has to poll until it is 0. - * - * We use atomic operations to access *drained_end_counter, because - * (1) when called from bdrv_set_aio_context_ignore(), the subgraph of - * @bs may contain nodes in different AioContexts, - * (2) bdrv_drain_all_end() uses the same counter for all nodes, - * regardless of which AioContext they are in. + * functions. */ static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents, - int *drained_end_counter) + BdrvChild *parent, bool ignore_bds_parents) { BdrvChild *child; int old_quiesce_counter; - assert(drained_end_counter != NULL); - if (qemu_in_coroutine()) { bdrv_co_yield_to_drain(bs, false, recursive, parent, ignore_bds_parents, - false, drained_end_counter); + false); return; } assert(bs->quiesce_counter > 0); /* Re-enable things in child-to-parent order */ - bdrv_drain_invoke(bs, false, drained_end_counter); - bdrv_parent_drained_end(bs, parent, ignore_bds_parents, - drained_end_counter); + bdrv_drain_invoke(bs, false); + bdrv_parent_drained_end(bs, parent, ignore_bds_parents); old_quiesce_counter = qatomic_fetch_dec(&bs->quiesce_counter); if (old_quiesce_counter == 1) { @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, assert(!ignore_bds_parents); bs->recursive_quiesce_counter--; QLIST_FOREACH(child, &bs->children, next) { - bdrv_do_drained_end(child->bs, true, child, ignore_bds_parents, - drained_end_counter); + bdrv_do_drained_end(child->bs, true, child, ignore_bds_parents); } } } void bdrv_drained_end(BlockDriverState *bs) { - int drained_end_counter = 0; IO_OR_GS_CODE(); - bdrv_do_drained_end(bs, false, NULL, false, &drained_end_counter); - BDRV_POLL_WHILE(bs, qatomic_read(&drained_end_counter) > 0); -} - -void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter) -{ - IO_CODE(); - bdrv_do_drained_end(bs, false, NULL, false, drained_end_counter); + bdrv_do_drained_end(bs, false, NULL, false); } void bdrv_subtree_drained_end(BlockDriverState *bs) { - int drained_end_counter = 0; IO_OR_GS_CODE(); - bdrv_do_drained_end(bs, true, NULL, false, &drained_end_counter); - BDRV_POLL_WHILE(bs, qatomic_read(&drained_end_counter) > 0); + bdrv_do_drained_end(bs, true, NULL, false); } void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent) @@ -XXX,XX +XXX,XX @@ void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent) void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent) { - int drained_end_counter = 0; int i; IO_OR_GS_CODE(); for (i = 0; i < old_parent->recursive_quiesce_counter; i++) { - bdrv_do_drained_end(child->bs, true, child, false, - &drained_end_counter); + bdrv_do_drained_end(child->bs, true, child, false); } - - BDRV_POLL_WHILE(child->bs, qatomic_read(&drained_end_counter) > 0); } void bdrv_drain(BlockDriverState *bs) @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) GLOBAL_STATE_CODE(); if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(NULL, true, false, NULL, true, true, NULL); + bdrv_co_yield_to_drain(NULL, true, false, NULL, true, true); return; } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) void bdrv_drain_all_end_quiesce(BlockDriverState *bs) { - int drained_end_counter = 0; GLOBAL_STATE_CODE(); g_assert(bs->quiesce_counter > 0); g_assert(!bs->refcnt); while (bs->quiesce_counter) { - bdrv_do_drained_end(bs, false, NULL, true, &drained_end_counter); + bdrv_do_drained_end(bs, false, NULL, true); } - BDRV_POLL_WHILE(bs, qatomic_read(&drained_end_counter) > 0); } void bdrv_drain_all_end(void) { BlockDriverState *bs = NULL; - int drained_end_counter = 0; GLOBAL_STATE_CODE(); /* @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void) AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - bdrv_do_drained_end(bs, false, NULL, true, &drained_end_counter); + bdrv_do_drained_end(bs, false, NULL, true); aio_context_release(aio_context); } assert(qemu_get_current_aio_context() == qemu_get_aio_context()); - AIO_WAIT_WHILE(NULL, qatomic_read(&drained_end_counter) > 0); - assert(bdrv_drain_all_count > 0); bdrv_drain_all_count--; } diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ static bool child_job_drained_poll(BdrvChild *c) } } -static void child_job_drained_end(BdrvChild *c, int *drained_end_counter) +static void child_job_drained_end(BdrvChild *c) { BlockJob *job = c->opaque; job_resume(&job->job); -- 2.38.1 bdrv_drain_invoke() has now two entirely separate cases that share no code any more and are selected depending on a bool parameter. Each case has only one caller. Just inline the function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-6-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/io.c | 23 ++++++----------------- 1 file changed, 6 insertions(+), 17 deletions(-) diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ typedef struct { bool ignore_bds_parents; } BdrvCoDrainData; -/* Recursively call BlockDriver.bdrv_drain_begin/end callbacks */ -static void bdrv_drain_invoke(BlockDriverState *bs, bool begin) -{ - if (!bs->drv || (begin && !bs->drv->bdrv_drain_begin) || - (!begin && !bs->drv->bdrv_drain_end)) { - return; - } - - if (begin) { - bs->drv->bdrv_drain_begin(bs); - } else { - bs->drv->bdrv_drain_end(bs); - } -} - /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */ bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, BdrvChild *ignore_parent, bool ignore_bds_parents) @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, } bdrv_parent_drained_begin(bs, parent, ignore_bds_parents); - bdrv_drain_invoke(bs, true); + if (bs->drv && bs->drv->bdrv_drain_begin) { + bs->drv->bdrv_drain_begin(bs); + } } static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, assert(bs->quiesce_counter > 0); /* Re-enable things in child-to-parent order */ - bdrv_drain_invoke(bs, false); + if (bs->drv && bs->drv->bdrv_drain_end) { + bs->drv->bdrv_drain_end(bs); + } bdrv_parent_drained_end(bs, parent, ignore_bds_parents); old_quiesce_counter = qatomic_fetch_dec(&bs->quiesce_counter); -- 2.38.1 Callers don't agree whether bdrv_reopen_queue_child() should be called with the AioContext lock held or not. Standardise on holding the lock (as done by QMP blockdev-reopen and the replication block driver) and fix bdrv_reopen() to do the same. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-7-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static bool bdrv_recurse_has_child(BlockDriverState *bs, * bs_queue, or the existing bs_queue being used. * * bs must be drained between bdrv_reopen_queue() and bdrv_reopen_multiple(). + * + * To be called with bs->aio_context locked. */ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, BlockDriverState *bs, @@ -XXX,XX +XXX,XX @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, return bs_queue; } +/* To be called with bs->aio_context locked */ BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, BlockDriverState *bs, QDict *options, bool keep_old_opts) @@ -XXX,XX +XXX,XX @@ int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, GLOBAL_STATE_CODE(); bdrv_subtree_drained_begin(bs); + queue = bdrv_reopen_queue(NULL, bs, opts, keep_old_opts); + if (ctx != qemu_get_aio_context()) { aio_context_release(ctx); } - - queue = bdrv_reopen_queue(NULL, bs, opts, keep_old_opts); ret = bdrv_reopen_multiple(queue, errp); if (ctx != qemu_get_aio_context()) { -- 2.38.1 bdrv_reopen() and friends use subtree drains as a lazy way of covering all the nodes they touch. Turns out that this lazy way is a lot more complicated than just draining the nodes individually, even not accounting for the additional complexity in the drain mechanism itself. Simplify the code by switching to draining the individual nodes that are already managed in the BlockReopenQueue anyway. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-8-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 16 +++++++++------- block/replication.c | 6 ------ blockdev.c | 13 ------------- 3 files changed, 9 insertions(+), 26 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static bool bdrv_recurse_has_child(BlockDriverState *bs, * returns a pointer to bs_queue, which is either the newly allocated * bs_queue, or the existing bs_queue being used. * - * bs must be drained between bdrv_reopen_queue() and bdrv_reopen_multiple(). + * bs is drained here and undrained by bdrv_reopen_queue_free(). * * To be called with bs->aio_context locked. */ @@ -XXX,XX +XXX,XX @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, int flags; QemuOpts *opts; - /* Make sure that the caller remembered to use a drained section. This is - * important to avoid graph changes between the recursive queuing here and - * bdrv_reopen_multiple(). */ - assert(bs->quiesce_counter > 0); GLOBAL_STATE_CODE(); + bdrv_drained_begin(bs); + if (bs_queue == NULL) { bs_queue = g_new0(BlockReopenQueue, 1); QTAILQ_INIT(bs_queue); @@ -XXX,XX +XXX,XX @@ void bdrv_reopen_queue_free(BlockReopenQueue *bs_queue) if (bs_queue) { BlockReopenQueueEntry *bs_entry, *next; QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { + AioContext *ctx = bdrv_get_aio_context(bs_entry->state.bs); + + aio_context_acquire(ctx); + bdrv_drained_end(bs_entry->state.bs); + aio_context_release(ctx); + qobject_unref(bs_entry->state.explicit_options); qobject_unref(bs_entry->state.options); g_free(bs_entry); @@ -XXX,XX +XXX,XX @@ int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, GLOBAL_STATE_CODE(); - bdrv_subtree_drained_begin(bs); queue = bdrv_reopen_queue(NULL, bs, opts, keep_old_opts); if (ctx != qemu_get_aio_context()) { @@ -XXX,XX +XXX,XX @@ int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, if (ctx != qemu_get_aio_context()) { aio_context_acquire(ctx); } - bdrv_subtree_drained_end(bs); return ret; } diff --git a/block/replication.c b/block/replication.c index XXXXXXX..XXXXXXX 100644 --- a/block/replication.c +++ b/block/replication.c @@ -XXX,XX +XXX,XX @@ static void reopen_backing_file(BlockDriverState *bs, bool writable, s->orig_secondary_read_only = bdrv_is_read_only(secondary_disk->bs); } - bdrv_subtree_drained_begin(hidden_disk->bs); - bdrv_subtree_drained_begin(secondary_disk->bs); - if (s->orig_hidden_read_only) { QDict *opts = qdict_new(); qdict_put_bool(opts, BDRV_OPT_READ_ONLY, !writable); @@ -XXX,XX +XXX,XX @@ static void reopen_backing_file(BlockDriverState *bs, bool writable, aio_context_acquire(ctx); } } - - bdrv_subtree_drained_end(hidden_disk->bs); - bdrv_subtree_drained_end(secondary_disk->bs); } static void backup_job_cleanup(BlockDriverState *bs) diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ fail: void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp) { BlockReopenQueue *queue = NULL; - GSList *drained = NULL; - GSList *p; /* Add each one of the BDS that we want to reopen to the queue */ for (; reopen_list != NULL; reopen_list = reopen_list->next) { @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp) ctx = bdrv_get_aio_context(bs); aio_context_acquire(ctx); - bdrv_subtree_drained_begin(bs); queue = bdrv_reopen_queue(queue, bs, qdict, false); - drained = g_slist_prepend(drained, bs); aio_context_release(ctx); } @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_reopen(BlockdevOptionsList *reopen_list, Error **errp) fail: bdrv_reopen_queue_free(queue); - for (p = drained; p; p = p->next) { - BlockDriverState *bs = p->data; - AioContext *ctx = bdrv_get_aio_context(bs); - - aio_context_acquire(ctx); - bdrv_subtree_drained_end(bs); - aio_context_release(ctx); - } - g_slist_free(drained); } void qmp_blockdev_del(const char *node_name, Error **errp) -- 2.38.1 Instead of using a subtree drain from the top node (which also drains child nodes of base that we're not even interested in), use a normal drain for base, which automatically drains all of the parents, too. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-9-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, GLOBAL_STATE_CODE(); bdrv_ref(top); - bdrv_subtree_drained_begin(top); + bdrv_drained_begin(base); if (!top->drv || !base->drv) { goto exit; @@ -XXX,XX +XXX,XX @@ int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, ret = 0; exit: - bdrv_subtree_drained_end(top); + bdrv_drained_end(base); bdrv_unref(top); return ret; } -- 2.38.1 The subtree drain was introduced in commit b1e1af394d9 as a way to avoid graph changes between finding the base node and changing the block graph as necessary on completion of the image streaming job. The block graph could change between these two points because bdrv_set_backing_hd() first drains the parent node, which involved polling and can do anything. Subtree draining was an imperfect way to make this less likely (because with it, fewer callbacks are called during this window). Everyone agreed that it's not really the right solution, and it was only committed as a stopgap solution. This replaces the subtree drain with a solution that simply drains the parent node before we try to find the base node, and then call a version of bdrv_set_backing_hd() that doesn't drain, but just asserts that the parent node is already drained. This way, any graph changes caused by draining happen before we start looking at the graph and things stay consistent between finding the base node and changing the graph. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-10-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-global-state.h | 3 +++ block.c | 17 ++++++++++++++--- block/stream.c | 26 ++++++++++++++++---------- 3 files changed, 33 insertions(+), 13 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -XXX,XX +XXX,XX @@ int bdrv_open_file_child(const char *filename, BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, Error **errp); +int bdrv_set_backing_hd_drained(BlockDriverState *bs, + BlockDriverState *backing_hd, + Error **errp); int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, const char *bdref_key, Error **errp); BlockDriverState *bdrv_open(const char *filename, const char *reference, diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static int bdrv_set_backing_noperm(BlockDriverState *bs, return bdrv_set_file_or_backing_noperm(bs, backing_hd, true, tran, errp); } -int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, - Error **errp) +int bdrv_set_backing_hd_drained(BlockDriverState *bs, + BlockDriverState *backing_hd, + Error **errp) { int ret; Transaction *tran = tran_new(); GLOBAL_STATE_CODE(); - bdrv_drained_begin(bs); + assert(bs->quiesce_counter > 0); ret = bdrv_set_backing_noperm(bs, backing_hd, tran, errp); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, ret = bdrv_refresh_perms(bs, tran, errp); out: tran_finalize(tran, ret); + return ret; +} +int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, + Error **errp) +{ + int ret; + GLOBAL_STATE_CODE(); + + bdrv_drained_begin(bs); + ret = bdrv_set_backing_hd_drained(bs, backing_hd, errp); bdrv_drained_end(bs); return ret; diff --git a/block/stream.c b/block/stream.c index XXXXXXX..XXXXXXX 100644 --- a/block/stream.c +++ b/block/stream.c @@ -XXX,XX +XXX,XX @@ static int stream_prepare(Job *job) bdrv_cor_filter_drop(s->cor_filter_bs); s->cor_filter_bs = NULL; - bdrv_subtree_drained_begin(s->above_base); + /* + * bdrv_set_backing_hd() requires that unfiltered_bs is drained. Drain + * already here and use bdrv_set_backing_hd_drained() instead because + * the polling during drained_begin() might change the graph, and if we do + * this only later, we may end up working with the wrong base node (or it + * might even have gone away by the time we want to use it). + */ + bdrv_drained_begin(unfiltered_bs); base = bdrv_filter_or_cow_bs(s->above_base); - if (base) { - bdrv_ref(base); - } - unfiltered_base = bdrv_skip_filters(base); if (bdrv_cow_child(unfiltered_bs)) { @@ -XXX,XX +XXX,XX @@ static int stream_prepare(Job *job) } } - bdrv_set_backing_hd(unfiltered_bs, base, &local_err); + bdrv_set_backing_hd_drained(unfiltered_bs, base, &local_err); + + /* + * This call will do I/O, so the graph can change again from here on. + * We have already completed the graph change, so we are not in danger + * of operating on the wrong node any more if this happens. + */ ret = bdrv_change_backing_file(unfiltered_bs, base_id, base_fmt, false); if (local_err) { error_report_err(local_err); @@ -XXX,XX +XXX,XX @@ static int stream_prepare(Job *job) } out: - if (base) { - bdrv_unref(base); - } - bdrv_subtree_drained_end(s->above_base); + bdrv_drained_end(unfiltered_bs); return ret; } -- 2.38.1 Subtree drains are not used any more. Remove them. After this, BdrvChildClass.attach/detach() don't poll any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-11-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 18 +-- include/block/block_int-common.h | 1 - include/block/block_int-io.h | 12 -- block.c | 20 +-- block/io.c | 121 +++----------- tests/unit/test-bdrv-drain.c | 261 ++----------------------------- 6 files changed, 44 insertions(+), 389 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_end_single(BdrvChild *c); /** * bdrv_drain_poll: * - * Poll for pending requests in @bs, its parents (except for @ignore_parent), - * and if @recursive is true its children as well (used for subtree drain). + * Poll for pending requests in @bs and its parents (except for @ignore_parent). * * If @ignore_bds_parents is true, parents that are BlockDriverStates must * ignore the drain request because they will be drained separately (used for @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_end_single(BdrvChild *c); * * This is part of bdrv_drained_begin. */ -bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, - BdrvChild *ignore_parent, bool ignore_bds_parents); +bool bdrv_drain_poll(BlockDriverState *bs, BdrvChild *ignore_parent, + bool ignore_bds_parents); /** * bdrv_drained_begin: @@ -XXX,XX +XXX,XX @@ void bdrv_drained_begin(BlockDriverState *bs); void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent, bool ignore_bds_parents); -/** - * Like bdrv_drained_begin, but recursively begins a quiesced section for - * exclusive access to all child nodes as well. - */ -void bdrv_subtree_drained_begin(BlockDriverState *bs); - /** * bdrv_drained_end: * @@ -XXX,XX +XXX,XX @@ void bdrv_subtree_drained_begin(BlockDriverState *bs); */ void bdrv_drained_end(BlockDriverState *bs); -/** - * End a quiescent section started by bdrv_subtree_drained_begin(). - */ -void bdrv_subtree_drained_end(BlockDriverState *bs); - #endif /* BLOCK_IO_H */ diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BlockDriverState { /* Accessed with atomic ops. */ int quiesce_counter; - int recursive_quiesce_counter; unsigned int write_gen; /* Current data generation */ diff --git a/include/block/block_int-io.h b/include/block/block_int-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-io.h +++ b/include/block/block_int-io.h @@ -XXX,XX +XXX,XX @@ void bdrv_bsc_invalidate_range(BlockDriverState *bs, */ void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes); - -/* - * "I/O or GS" API functions. These functions can run without - * the BQL, but only in one specific iothread/main loop. - * - * See include/block/block-io.h for more information about - * the "I/O or GS" API. - */ - -void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); -void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); - #endif /* BLOCK_INT_IO_H */ diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_drained_begin(BdrvChild *child) static bool bdrv_child_cb_drained_poll(BdrvChild *child) { BlockDriverState *bs = child->opaque; - return bdrv_drain_poll(bs, false, NULL, false); + return bdrv_drain_poll(bs, NULL, false); } static void bdrv_child_cb_drained_end(BdrvChild *child) @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_attach(BdrvChild *child) assert(!bs->file); bs->file = child; } - - bdrv_apply_subtree_drain(child, bs); } static void bdrv_child_cb_detach(BdrvChild *child) @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_detach(BdrvChild *child) bdrv_backing_detach(child); } - bdrv_unapply_subtree_drain(child, bs); - assert_bdrv_graph_writable(bs); QLIST_REMOVE(child, next); if (child == bs->backing) { @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, } if (old_bs) { - /* Detach first so that the recursive drain sections coming from @child - * are already gone and we only end the drain sections that came from - * elsewhere. */ if (child->klass->detach) { child->klass->detach(child); } @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent); /* - * Detaching the old node may have led to the new node's - * quiesce_counter having been decreased. Not a problem, we - * just need to recognize this here and then invoke - * drained_end appropriately more often. + * Polling in bdrv_parent_drained_begin_single() may have led to the new + * node's quiesce_counter having been decreased. Not a problem, we just + * need to recognize this here and then invoke drained_end appropriately + * more often. */ assert(new_bs->quiesce_counter <= new_bs_quiesce_counter); drain_saldo += new_bs->quiesce_counter - new_bs_quiesce_counter; - /* Attach only after starting new drained sections, so that recursive - * drain sections coming from @child don't get an extra .drained_begin - * callback. */ if (child->klass->attach) { child->klass->attach(child); } diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ typedef struct { BlockDriverState *bs; bool done; bool begin; - bool recursive; bool poll; BdrvChild *parent; bool ignore_bds_parents; } BdrvCoDrainData; /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */ -bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, - BdrvChild *ignore_parent, bool ignore_bds_parents) +bool bdrv_drain_poll(BlockDriverState *bs, BdrvChild *ignore_parent, + bool ignore_bds_parents) { - BdrvChild *child, *next; IO_OR_GS_CODE(); if (bdrv_parent_drained_poll(bs, ignore_parent, ignore_bds_parents)) { @@ -XXX,XX +XXX,XX @@ bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, return true; } - if (recursive) { - assert(!ignore_bds_parents); - QLIST_FOREACH_SAFE(child, &bs->children, next, next) { - if (bdrv_drain_poll(child->bs, recursive, child, false)) { - return true; - } - } - } - return false; } -static bool bdrv_drain_poll_top_level(BlockDriverState *bs, bool recursive, +static bool bdrv_drain_poll_top_level(BlockDriverState *bs, BdrvChild *ignore_parent) { - return bdrv_drain_poll(bs, recursive, ignore_parent, false); + return bdrv_drain_poll(bs, ignore_parent, false); } -static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents, - bool poll); -static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents); +static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, + bool ignore_bds_parents, bool poll); +static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, + bool ignore_bds_parents); static void bdrv_co_drain_bh_cb(void *opaque) { @@ -XXX,XX +XXX,XX @@ static void bdrv_co_drain_bh_cb(void *opaque) aio_context_acquire(ctx); bdrv_dec_in_flight(bs); if (data->begin) { - bdrv_do_drained_begin(bs, data->recursive, data->parent, - data->ignore_bds_parents, data->poll); + bdrv_do_drained_begin(bs, data->parent, data->ignore_bds_parents, + data->poll); } else { assert(!data->poll); - bdrv_do_drained_end(bs, data->recursive, data->parent, - data->ignore_bds_parents); + bdrv_do_drained_end(bs, data->parent, data->ignore_bds_parents); } aio_context_release(ctx); } else { @@ -XXX,XX +XXX,XX @@ static void bdrv_co_drain_bh_cb(void *opaque) } static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, - bool begin, bool recursive, + bool begin, BdrvChild *parent, bool ignore_bds_parents, bool poll) @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, .bs = bs, .done = false, .begin = begin, - .recursive = recursive, .parent = parent, .ignore_bds_parents = ignore_bds_parents, .poll = poll, @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, } } -static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents, - bool poll) +static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, + bool ignore_bds_parents, bool poll) { - BdrvChild *child, *next; - if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, true, recursive, parent, ignore_bds_parents, - poll); + bdrv_co_yield_to_drain(bs, true, parent, ignore_bds_parents, poll); return; } bdrv_do_drained_begin_quiesce(bs, parent, ignore_bds_parents); - if (recursive) { - assert(!ignore_bds_parents); - bs->recursive_quiesce_counter++; - QLIST_FOREACH_SAFE(child, &bs->children, next, next) { - bdrv_do_drained_begin(child->bs, true, child, ignore_bds_parents, - false); - } - } - /* * Wait for drained requests to finish. * @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, bool recursive, */ if (poll) { assert(!ignore_bds_parents); - BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, recursive, parent)); + BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, parent)); } } void bdrv_drained_begin(BlockDriverState *bs) { IO_OR_GS_CODE(); - bdrv_do_drained_begin(bs, false, NULL, false, true); -} - -void bdrv_subtree_drained_begin(BlockDriverState *bs) -{ - IO_OR_GS_CODE(); - bdrv_do_drained_begin(bs, true, NULL, false, true); + bdrv_do_drained_begin(bs, NULL, false, true); } /** * This function does not poll, nor must any of its recursively called * functions. */ -static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, - BdrvChild *parent, bool ignore_bds_parents) +static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, + bool ignore_bds_parents) { - BdrvChild *child; int old_quiesce_counter; if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, false, recursive, parent, ignore_bds_parents, - false); + bdrv_co_yield_to_drain(bs, false, parent, ignore_bds_parents, false); return; } assert(bs->quiesce_counter > 0); @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, bool recursive, if (old_quiesce_counter == 1) { aio_enable_external(bdrv_get_aio_context(bs)); } - - if (recursive) { - assert(!ignore_bds_parents); - bs->recursive_quiesce_counter--; - QLIST_FOREACH(child, &bs->children, next) { - bdrv_do_drained_end(child->bs, true, child, ignore_bds_parents); - } - } } void bdrv_drained_end(BlockDriverState *bs) { IO_OR_GS_CODE(); - bdrv_do_drained_end(bs, false, NULL, false); -} - -void bdrv_subtree_drained_end(BlockDriverState *bs) -{ - IO_OR_GS_CODE(); - bdrv_do_drained_end(bs, true, NULL, false); -} - -void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent) -{ - int i; - IO_OR_GS_CODE(); - - for (i = 0; i < new_parent->recursive_quiesce_counter; i++) { - bdrv_do_drained_begin(child->bs, true, child, false, true); - } -} - -void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent) -{ - int i; - IO_OR_GS_CODE(); - - for (i = 0; i < old_parent->recursive_quiesce_counter; i++) { - bdrv_do_drained_end(child->bs, true, child, false); - } + bdrv_do_drained_end(bs, NULL, false); } void bdrv_drain(BlockDriverState *bs) @@ -XXX,XX +XXX,XX @@ static bool bdrv_drain_all_poll(void) while ((bs = bdrv_next_all_states(bs))) { AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - result |= bdrv_drain_poll(bs, false, NULL, true); + result |= bdrv_drain_poll(bs, NULL, true); aio_context_release(aio_context); } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) GLOBAL_STATE_CODE(); if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(NULL, true, false, NULL, true, true); + bdrv_co_yield_to_drain(NULL, true, NULL, true, true); return; } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - bdrv_do_drained_begin(bs, false, NULL, true, false); + bdrv_do_drained_begin(bs, NULL, true, false); aio_context_release(aio_context); } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end_quiesce(BlockDriverState *bs) g_assert(!bs->refcnt); while (bs->quiesce_counter) { - bdrv_do_drained_end(bs, false, NULL, true); + bdrv_do_drained_end(bs, NULL, true); } } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void) AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - bdrv_do_drained_end(bs, false, NULL, true); + bdrv_do_drained_end(bs, NULL, true); aio_context_release(aio_context); } diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ static void call_in_coroutine(void (*entry)(void)) enum drain_type { BDRV_DRAIN_ALL, BDRV_DRAIN, - BDRV_SUBTREE_DRAIN, DRAIN_TYPE_MAX, }; @@ -XXX,XX +XXX,XX @@ static void do_drain_begin(enum drain_type drain_type, BlockDriverState *bs) switch (drain_type) { case BDRV_DRAIN_ALL: bdrv_drain_all_begin(); break; case BDRV_DRAIN: bdrv_drained_begin(bs); break; - case BDRV_SUBTREE_DRAIN: bdrv_subtree_drained_begin(bs); break; default: g_assert_not_reached(); } } @@ -XXX,XX +XXX,XX @@ static void do_drain_end(enum drain_type drain_type, BlockDriverState *bs) switch (drain_type) { case BDRV_DRAIN_ALL: bdrv_drain_all_end(); break; case BDRV_DRAIN: bdrv_drained_end(bs); break; - case BDRV_SUBTREE_DRAIN: bdrv_subtree_drained_end(bs); break; default: g_assert_not_reached(); } } @@ -XXX,XX +XXX,XX @@ static void test_drv_cb_drain(void) test_drv_cb_common(BDRV_DRAIN, false); } -static void test_drv_cb_drain_subtree(void) -{ - test_drv_cb_common(BDRV_SUBTREE_DRAIN, true); -} - static void test_drv_cb_co_drain_all(void) { call_in_coroutine(test_drv_cb_drain_all); @@ -XXX,XX +XXX,XX @@ static void test_drv_cb_co_drain(void) call_in_coroutine(test_drv_cb_drain); } -static void test_drv_cb_co_drain_subtree(void) -{ - call_in_coroutine(test_drv_cb_drain_subtree); -} - static void test_quiesce_common(enum drain_type drain_type, bool recursive) { BlockBackend *blk; @@ -XXX,XX +XXX,XX @@ static void test_quiesce_drain(void) test_quiesce_common(BDRV_DRAIN, false); } -static void test_quiesce_drain_subtree(void) -{ - test_quiesce_common(BDRV_SUBTREE_DRAIN, true); -} - static void test_quiesce_co_drain_all(void) { call_in_coroutine(test_quiesce_drain_all); @@ -XXX,XX +XXX,XX @@ static void test_quiesce_co_drain(void) call_in_coroutine(test_quiesce_drain); } -static void test_quiesce_co_drain_subtree(void) -{ - call_in_coroutine(test_quiesce_drain_subtree); -} - static void test_nested(void) { BlockBackend *blk; @@ -XXX,XX +XXX,XX @@ static void test_nested(void) blk_unref(blk); } -static void test_multiparent(void) -{ - BlockBackend *blk_a, *blk_b; - BlockDriverState *bs_a, *bs_b, *backing; - BDRVTestState *a_s, *b_s, *backing_s; - - blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); - bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR, - &error_abort); - a_s = bs_a->opaque; - blk_insert_bs(blk_a, bs_a, &error_abort); - - blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); - bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR, - &error_abort); - b_s = bs_b->opaque; - blk_insert_bs(blk_b, bs_b, &error_abort); - - backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort); - backing_s = backing->opaque; - bdrv_set_backing_hd(bs_a, backing, &error_abort); - bdrv_set_backing_hd(bs_b, backing, &error_abort); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 0); - g_assert_cmpint(bs_b->quiesce_counter, ==, 0); - g_assert_cmpint(backing->quiesce_counter, ==, 0); - g_assert_cmpint(a_s->drain_count, ==, 0); - g_assert_cmpint(b_s->drain_count, ==, 0); - g_assert_cmpint(backing_s->drain_count, ==, 0); - - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 1); - g_assert_cmpint(bs_b->quiesce_counter, ==, 1); - g_assert_cmpint(backing->quiesce_counter, ==, 1); - g_assert_cmpint(a_s->drain_count, ==, 1); - g_assert_cmpint(b_s->drain_count, ==, 1); - g_assert_cmpint(backing_s->drain_count, ==, 1); - - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 2); - g_assert_cmpint(bs_b->quiesce_counter, ==, 2); - g_assert_cmpint(backing->quiesce_counter, ==, 2); - g_assert_cmpint(a_s->drain_count, ==, 2); - g_assert_cmpint(b_s->drain_count, ==, 2); - g_assert_cmpint(backing_s->drain_count, ==, 2); - - do_drain_end(BDRV_SUBTREE_DRAIN, bs_b); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 1); - g_assert_cmpint(bs_b->quiesce_counter, ==, 1); - g_assert_cmpint(backing->quiesce_counter, ==, 1); - g_assert_cmpint(a_s->drain_count, ==, 1); - g_assert_cmpint(b_s->drain_count, ==, 1); - g_assert_cmpint(backing_s->drain_count, ==, 1); - - do_drain_end(BDRV_SUBTREE_DRAIN, bs_a); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 0); - g_assert_cmpint(bs_b->quiesce_counter, ==, 0); - g_assert_cmpint(backing->quiesce_counter, ==, 0); - g_assert_cmpint(a_s->drain_count, ==, 0); - g_assert_cmpint(b_s->drain_count, ==, 0); - g_assert_cmpint(backing_s->drain_count, ==, 0); - - bdrv_unref(backing); - bdrv_unref(bs_a); - bdrv_unref(bs_b); - blk_unref(blk_a); - blk_unref(blk_b); -} - -static void test_graph_change_drain_subtree(void) -{ - BlockBackend *blk_a, *blk_b; - BlockDriverState *bs_a, *bs_b, *backing; - BDRVTestState *a_s, *b_s, *backing_s; - - blk_a = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); - bs_a = bdrv_new_open_driver(&bdrv_test, "test-node-a", BDRV_O_RDWR, - &error_abort); - a_s = bs_a->opaque; - blk_insert_bs(blk_a, bs_a, &error_abort); - - blk_b = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL); - bs_b = bdrv_new_open_driver(&bdrv_test, "test-node-b", BDRV_O_RDWR, - &error_abort); - b_s = bs_b->opaque; - blk_insert_bs(blk_b, bs_b, &error_abort); - - backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort); - backing_s = backing->opaque; - bdrv_set_backing_hd(bs_a, backing, &error_abort); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 0); - g_assert_cmpint(bs_b->quiesce_counter, ==, 0); - g_assert_cmpint(backing->quiesce_counter, ==, 0); - g_assert_cmpint(a_s->drain_count, ==, 0); - g_assert_cmpint(b_s->drain_count, ==, 0); - g_assert_cmpint(backing_s->drain_count, ==, 0); - - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a); - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a); - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_a); - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b); - do_drain_begin(BDRV_SUBTREE_DRAIN, bs_b); - - bdrv_set_backing_hd(bs_b, backing, &error_abort); - g_assert_cmpint(bs_a->quiesce_counter, ==, 5); - g_assert_cmpint(bs_b->quiesce_counter, ==, 5); - g_assert_cmpint(backing->quiesce_counter, ==, 5); - g_assert_cmpint(a_s->drain_count, ==, 5); - g_assert_cmpint(b_s->drain_count, ==, 5); - g_assert_cmpint(backing_s->drain_count, ==, 5); - - bdrv_set_backing_hd(bs_b, NULL, &error_abort); - g_assert_cmpint(bs_a->quiesce_counter, ==, 3); - g_assert_cmpint(bs_b->quiesce_counter, ==, 2); - g_assert_cmpint(backing->quiesce_counter, ==, 3); - g_assert_cmpint(a_s->drain_count, ==, 3); - g_assert_cmpint(b_s->drain_count, ==, 2); - g_assert_cmpint(backing_s->drain_count, ==, 3); - - bdrv_set_backing_hd(bs_b, backing, &error_abort); - g_assert_cmpint(bs_a->quiesce_counter, ==, 5); - g_assert_cmpint(bs_b->quiesce_counter, ==, 5); - g_assert_cmpint(backing->quiesce_counter, ==, 5); - g_assert_cmpint(a_s->drain_count, ==, 5); - g_assert_cmpint(b_s->drain_count, ==, 5); - g_assert_cmpint(backing_s->drain_count, ==, 5); - - do_drain_end(BDRV_SUBTREE_DRAIN, bs_b); - do_drain_end(BDRV_SUBTREE_DRAIN, bs_b); - do_drain_end(BDRV_SUBTREE_DRAIN, bs_a); - do_drain_end(BDRV_SUBTREE_DRAIN, bs_a); - do_drain_end(BDRV_SUBTREE_DRAIN, bs_a); - - g_assert_cmpint(bs_a->quiesce_counter, ==, 0); - g_assert_cmpint(bs_b->quiesce_counter, ==, 0); - g_assert_cmpint(backing->quiesce_counter, ==, 0); - g_assert_cmpint(a_s->drain_count, ==, 0); - g_assert_cmpint(b_s->drain_count, ==, 0); - g_assert_cmpint(backing_s->drain_count, ==, 0); - - bdrv_unref(backing); - bdrv_unref(bs_a); - bdrv_unref(bs_b); - blk_unref(blk_a); - blk_unref(blk_b); -} - static void test_graph_change_drain_all(void) { BlockBackend *blk_a, *blk_b; @@ -XXX,XX +XXX,XX @@ static void test_iothread_drain(void) test_iothread_common(BDRV_DRAIN, 1); } -static void test_iothread_drain_subtree(void) -{ - test_iothread_common(BDRV_SUBTREE_DRAIN, 0); - test_iothread_common(BDRV_SUBTREE_DRAIN, 1); -} - typedef struct TestBlockJob { BlockJob common; @@ -XXX,XX +XXX,XX @@ enum test_job_result { enum test_job_drain_node { TEST_JOB_DRAIN_SRC, TEST_JOB_DRAIN_SRC_CHILD, - TEST_JOB_DRAIN_SRC_PARENT, }; static void test_blockjob_common_drain_node(enum drain_type drain_type, @@ -XXX,XX +XXX,XX @@ static void test_blockjob_common_drain_node(enum drain_type drain_type, case TEST_JOB_DRAIN_SRC_CHILD: drain_bs = src_backing; break; - case TEST_JOB_DRAIN_SRC_PARENT: - drain_bs = src_overlay; - break; default: g_assert_not_reached(); } @@ -XXX,XX +XXX,XX @@ static void test_blockjob_common(enum drain_type drain_type, bool use_iothread, TEST_JOB_DRAIN_SRC); test_blockjob_common_drain_node(drain_type, use_iothread, result, TEST_JOB_DRAIN_SRC_CHILD); - if (drain_type == BDRV_SUBTREE_DRAIN) { - test_blockjob_common_drain_node(drain_type, use_iothread, result, - TEST_JOB_DRAIN_SRC_PARENT); - } } static void test_blockjob_drain_all(void) @@ -XXX,XX +XXX,XX @@ static void test_blockjob_drain(void) test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_SUCCESS); } -static void test_blockjob_drain_subtree(void) -{ - test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_SUCCESS); -} - static void test_blockjob_error_drain_all(void) { test_blockjob_common(BDRV_DRAIN_ALL, false, TEST_JOB_FAIL_RUN); @@ -XXX,XX +XXX,XX @@ static void test_blockjob_error_drain(void) test_blockjob_common(BDRV_DRAIN, false, TEST_JOB_FAIL_PREPARE); } -static void test_blockjob_error_drain_subtree(void) -{ - test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_FAIL_RUN); - test_blockjob_common(BDRV_SUBTREE_DRAIN, false, TEST_JOB_FAIL_PREPARE); -} - static void test_blockjob_iothread_drain_all(void) { test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_SUCCESS); @@ -XXX,XX +XXX,XX @@ static void test_blockjob_iothread_drain(void) test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_SUCCESS); } -static void test_blockjob_iothread_drain_subtree(void) -{ - test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_SUCCESS); -} - static void test_blockjob_iothread_error_drain_all(void) { test_blockjob_common(BDRV_DRAIN_ALL, true, TEST_JOB_FAIL_RUN); @@ -XXX,XX +XXX,XX @@ static void test_blockjob_iothread_error_drain(void) test_blockjob_common(BDRV_DRAIN, true, TEST_JOB_FAIL_PREPARE); } -static void test_blockjob_iothread_error_drain_subtree(void) -{ - test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_FAIL_RUN); - test_blockjob_common(BDRV_SUBTREE_DRAIN, true, TEST_JOB_FAIL_PREPARE); -} - typedef struct BDRVTestTopState { BdrvChild *wait_child; @@ -XXX,XX +XXX,XX @@ static void do_test_delete_by_drain(bool detach_instead_of_delete, bdrv_drain(child_bs); bdrv_unref(child_bs); break; - case BDRV_SUBTREE_DRAIN: - /* Would have to ref/unref bs here for !detach_instead_of_delete, but - * then the whole test becomes pointless because the graph changes - * don't occur during the drain any more. */ - assert(detach_instead_of_delete); - bdrv_subtree_drained_begin(bs); - bdrv_subtree_drained_end(bs); - break; case BDRV_DRAIN_ALL: bdrv_drain_all_begin(); bdrv_drain_all_end(); @@ -XXX,XX +XXX,XX @@ static void test_detach_by_drain(void) do_test_delete_by_drain(true, BDRV_DRAIN); } -static void test_detach_by_drain_subtree(void) -{ - do_test_delete_by_drain(true, BDRV_SUBTREE_DRAIN); -} - struct detach_by_parent_data { BlockDriverState *parent_b; @@ -XXX,XX +XXX,XX @@ static void test_detach_indirect(bool by_parent_cb) g_assert(acb != NULL); /* Drain and check the expected result */ - bdrv_subtree_drained_begin(parent_b); + bdrv_drained_begin(parent_b); + bdrv_drained_begin(a); + bdrv_drained_begin(b); + bdrv_drained_begin(c); g_assert(detach_by_parent_data.child_c != NULL); @@ -XXX,XX +XXX,XX @@ static void test_detach_indirect(bool by_parent_cb) g_assert(QLIST_NEXT(child_a, next) == NULL); g_assert_cmpint(parent_a->quiesce_counter, ==, 1); - g_assert_cmpint(parent_b->quiesce_counter, ==, 1); + g_assert_cmpint(parent_b->quiesce_counter, ==, 3); g_assert_cmpint(a->quiesce_counter, ==, 1); - g_assert_cmpint(b->quiesce_counter, ==, 0); + g_assert_cmpint(b->quiesce_counter, ==, 1); g_assert_cmpint(c->quiesce_counter, ==, 1); - bdrv_subtree_drained_end(parent_b); + bdrv_drained_end(parent_b); + bdrv_drained_end(a); + bdrv_drained_end(b); + bdrv_drained_end(c); bdrv_unref(parent_b); blk_unref(blk); @@ -XXX,XX +XXX,XX @@ int main(int argc, char **argv) g_test_add_func("/bdrv-drain/driver-cb/drain_all", test_drv_cb_drain_all); g_test_add_func("/bdrv-drain/driver-cb/drain", test_drv_cb_drain); - g_test_add_func("/bdrv-drain/driver-cb/drain_subtree", - test_drv_cb_drain_subtree); g_test_add_func("/bdrv-drain/driver-cb/co/drain_all", test_drv_cb_co_drain_all); g_test_add_func("/bdrv-drain/driver-cb/co/drain", test_drv_cb_co_drain); - g_test_add_func("/bdrv-drain/driver-cb/co/drain_subtree", - test_drv_cb_co_drain_subtree); - g_test_add_func("/bdrv-drain/quiesce/drain_all", test_quiesce_drain_all); g_test_add_func("/bdrv-drain/quiesce/drain", test_quiesce_drain); - g_test_add_func("/bdrv-drain/quiesce/drain_subtree", - test_quiesce_drain_subtree); g_test_add_func("/bdrv-drain/quiesce/co/drain_all", test_quiesce_co_drain_all); g_test_add_func("/bdrv-drain/quiesce/co/drain", test_quiesce_co_drain); - g_test_add_func("/bdrv-drain/quiesce/co/drain_subtree", - test_quiesce_co_drain_subtree); g_test_add_func("/bdrv-drain/nested", test_nested); - g_test_add_func("/bdrv-drain/multiparent", test_multiparent); - g_test_add_func("/bdrv-drain/graph-change/drain_subtree", - test_graph_change_drain_subtree); g_test_add_func("/bdrv-drain/graph-change/drain_all", test_graph_change_drain_all); g_test_add_func("/bdrv-drain/iothread/drain_all", test_iothread_drain_all); g_test_add_func("/bdrv-drain/iothread/drain", test_iothread_drain); - g_test_add_func("/bdrv-drain/iothread/drain_subtree", - test_iothread_drain_subtree); g_test_add_func("/bdrv-drain/blockjob/drain_all", test_blockjob_drain_all); g_test_add_func("/bdrv-drain/blockjob/drain", test_blockjob_drain); - g_test_add_func("/bdrv-drain/blockjob/drain_subtree", - test_blockjob_drain_subtree); g_test_add_func("/bdrv-drain/blockjob/error/drain_all", test_blockjob_error_drain_all); g_test_add_func("/bdrv-drain/blockjob/error/drain", test_blockjob_error_drain); - g_test_add_func("/bdrv-drain/blockjob/error/drain_subtree", - test_blockjob_error_drain_subtree); g_test_add_func("/bdrv-drain/blockjob/iothread/drain_all", test_blockjob_iothread_drain_all); g_test_add_func("/bdrv-drain/blockjob/iothread/drain", test_blockjob_iothread_drain); - g_test_add_func("/bdrv-drain/blockjob/iothread/drain_subtree", - test_blockjob_iothread_drain_subtree); g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain_all", test_blockjob_iothread_error_drain_all); g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain", test_blockjob_iothread_error_drain); - g_test_add_func("/bdrv-drain/blockjob/iothread/error/drain_subtree", - test_blockjob_iothread_error_drain_subtree); g_test_add_func("/bdrv-drain/deletion/drain", test_delete_by_drain); g_test_add_func("/bdrv-drain/detach/drain_all", test_detach_by_drain_all); g_test_add_func("/bdrv-drain/detach/drain", test_detach_by_drain); - g_test_add_func("/bdrv-drain/detach/drain_subtree", test_detach_by_drain_subtree); g_test_add_func("/bdrv-drain/detach/parent_cb", test_detach_by_parent_cb); g_test_add_func("/bdrv-drain/detach/driver_cb", test_detach_by_driver_cb); -- 2.38.1 We only need to call both the BlockDriver's callback and the parent callbacks when going from undrained to drained or vice versa. A second drain section doesn't make a difference for the driver or the parent, they weren't supposed to send new requests before and after the second drain. One thing that gets in the way is the 'ignore_bds_parents' parameter in bdrv_do_drained_begin_quiesce() and bdrv_do_drained_end(): It means that bdrv_drain_all_begin() increases bs->quiesce_counter, but does not quiesce the parent through BdrvChildClass callbacks. If an additional drain section is started now, bs->quiesce_counter will be non-zero, but we would still need to quiesce the parent through BdrvChildClass in order to keep things consistent (and unquiesce it on the matching bdrv_drained_end(), even though the counter would not reach 0 yet as long as the bdrv_drain_all() section is still active). Instead of keeping track of this, let's just get rid of the parameter. It was introduced in commit 6cd5c9d7b2d as an optimisation so that during bdrv_drain_all(), we wouldn't recursively drain all parents up to the root for each node, resulting in quadratic complexity. As it happens, calling the callbacks only once solves the same problem, so as of this patch, we'll still have O(n) complexity and ignore_bds_parents is not needed any more. This patch only ignores the 'ignore_bds_parents' parameter. It will be removed in a separate patch. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-12-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block_int-common.h | 8 ++++---- block.c | 25 +++++++------------------ block/io.c | 30 ++++++++++++++++++------------ tests/unit/test-bdrv-drain.c | 16 ++++++++++------ 4 files changed, 39 insertions(+), 40 deletions(-) diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BdrvChild { bool frozen; /* - * How many times the parent of this child has been drained + * True if the parent of this child has been drained by this BdrvChild * (through klass->drained_*). - * Usually, this is equal to bs->quiesce_counter (potentially - * reduced by bdrv_drain_all_count). It may differ while the + * + * It is generally true if bs->quiesce_counter > 0. It may differ while the * child is entering or leaving a drained section. */ - int parent_quiesce_counter; + bool quiesced_parent; QLIST_ENTRY(BdrvChild) next; QLIST_ENTRY(BdrvChild) next_parent; diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, { BlockDriverState *old_bs = child->bs; int new_bs_quiesce_counter; - int drain_saldo; assert(!child->frozen); assert(old_bs != new_bs); @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)); } - new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); - drain_saldo = new_bs_quiesce_counter - child->parent_quiesce_counter; - /* * If the new child node is drained but the old one was not, flush * all outstanding requests to the old child node. */ - while (drain_saldo > 0 && child->klass->drained_begin) { + new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); + if (new_bs_quiesce_counter && !child->quiesced_parent) { bdrv_parent_drained_begin_single(child, true); - drain_saldo--; } if (old_bs) { @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, if (new_bs) { assert_bdrv_graph_writable(new_bs); QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent); - - /* - * Polling in bdrv_parent_drained_begin_single() may have led to the new - * node's quiesce_counter having been decreased. Not a problem, we just - * need to recognize this here and then invoke drained_end appropriately - * more often. - */ - assert(new_bs->quiesce_counter <= new_bs_quiesce_counter); - drain_saldo += new_bs->quiesce_counter - new_bs_quiesce_counter; - if (child->klass->attach) { child->klass->attach(child); } @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, /* * If the old child node was drained but the new one is not, allow * requests to come in only after the new node has been attached. + * + * Update new_bs_quiesce_counter because bdrv_parent_drained_begin_single() + * polls, which could have changed the value. */ - while (drain_saldo < 0 && child->klass->drained_end) { + new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); + if (!new_bs_quiesce_counter && child->quiesced_parent) { bdrv_parent_drained_end_single(child); - drain_saldo++; } } diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_end_single(BdrvChild *c) { IO_OR_GS_CODE(); - assert(c->parent_quiesce_counter > 0); - c->parent_quiesce_counter--; + assert(c->quiesced_parent); + c->quiesced_parent = false; + if (c->klass->drained_end) { c->klass->drained_end(c); } @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll) { AioContext *ctx = bdrv_child_get_parent_aio_context(c); IO_OR_GS_CODE(); - c->parent_quiesce_counter++; + + assert(!c->quiesced_parent); + c->quiesced_parent = true; + if (c->klass->drained_begin) { c->klass->drained_begin(c); } @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, /* Stop things in parent-to-child order */ if (qatomic_fetch_inc(&bs->quiesce_counter) == 0) { aio_disable_external(bdrv_get_aio_context(bs)); - } - bdrv_parent_drained_begin(bs, parent, ignore_bds_parents); - if (bs->drv && bs->drv->bdrv_drain_begin) { - bs->drv->bdrv_drain_begin(bs); + /* TODO Remove ignore_bds_parents, we don't consider it any more */ + bdrv_parent_drained_begin(bs, parent, false); + if (bs->drv && bs->drv->bdrv_drain_begin) { + bs->drv->bdrv_drain_begin(bs); + } } } @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, assert(bs->quiesce_counter > 0); /* Re-enable things in child-to-parent order */ - if (bs->drv && bs->drv->bdrv_drain_end) { - bs->drv->bdrv_drain_end(bs); - } - bdrv_parent_drained_end(bs, parent, ignore_bds_parents); - old_quiesce_counter = qatomic_fetch_dec(&bs->quiesce_counter); if (old_quiesce_counter == 1) { + if (bs->drv && bs->drv->bdrv_drain_end) { + bs->drv->bdrv_drain_end(bs); + } + /* TODO Remove ignore_bds_parents, we don't consider it any more */ + bdrv_parent_drained_end(bs, parent, false); + aio_enable_external(bdrv_get_aio_context(bs)); } } diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ static void test_quiesce_common(enum drain_type drain_type, bool recursive) do_drain_begin(drain_type, bs); - g_assert_cmpint(bs->quiesce_counter, ==, 1); + if (drain_type == BDRV_DRAIN_ALL) { + g_assert_cmpint(bs->quiesce_counter, ==, 2); + } else { + g_assert_cmpint(bs->quiesce_counter, ==, 1); + } g_assert_cmpint(backing->quiesce_counter, ==, !!recursive); do_drain_end(drain_type, bs); @@ -XXX,XX +XXX,XX @@ static void test_nested(void) for (outer = 0; outer < DRAIN_TYPE_MAX; outer++) { for (inner = 0; inner < DRAIN_TYPE_MAX; inner++) { - int backing_quiesce = (outer != BDRV_DRAIN) + - (inner != BDRV_DRAIN); + int backing_quiesce = (outer == BDRV_DRAIN_ALL) + + (inner == BDRV_DRAIN_ALL); g_assert_cmpint(bs->quiesce_counter, ==, 0); g_assert_cmpint(backing->quiesce_counter, ==, 0); @@ -XXX,XX +XXX,XX @@ static void test_nested(void) do_drain_begin(outer, bs); do_drain_begin(inner, bs); - g_assert_cmpint(bs->quiesce_counter, ==, 2); + g_assert_cmpint(bs->quiesce_counter, ==, 2 + !!backing_quiesce); g_assert_cmpint(backing->quiesce_counter, ==, backing_quiesce); - g_assert_cmpint(s->drain_count, ==, 2); - g_assert_cmpint(backing_s->drain_count, ==, backing_quiesce); + g_assert_cmpint(s->drain_count, ==, 1); + g_assert_cmpint(backing_s->drain_count, ==, !!backing_quiesce); do_drain_end(inner, bs); do_drain_end(outer, bs); -- 2.38.1 ignore_bds_parents is now ignored during drain_begin and drain_end, so we can just remove it there. It is still a valid optimisation for drain_all in bdrv_drained_poll(), so leave it around there. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-13-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 3 +-- block.c | 2 +- block/io.c | 58 +++++++++++++++------------------------- 3 files changed, 24 insertions(+), 39 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ void bdrv_drained_begin(BlockDriverState *bs); * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already * running requests to complete. */ -void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, - BdrvChild *parent, bool ignore_bds_parents); +void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent); /** * bdrv_drained_end: diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static char *bdrv_child_get_parent_desc(BdrvChild *c) static void bdrv_child_cb_drained_begin(BdrvChild *child) { BlockDriverState *bs = child->opaque; - bdrv_do_drained_begin_quiesce(bs, NULL, false); + bdrv_do_drained_begin_quiesce(bs, NULL); } static bool bdrv_child_cb_drained_poll(BdrvChild *child) diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static void bdrv_parent_cb_resize(BlockDriverState *bs); static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes, BdrvRequestFlags flags); -static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore, - bool ignore_bds_parents) +static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore) { BdrvChild *c, *next; QLIST_FOREACH_SAFE(c, &bs->parents, next_parent, next) { - if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) { + if (c == ignore) { continue; } bdrv_parent_drained_begin_single(c, false); @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_end_single(BdrvChild *c) } } -static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore, - bool ignore_bds_parents) +static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore) { BdrvChild *c; QLIST_FOREACH(c, &bs->parents, next_parent) { - if (c == ignore || (ignore_bds_parents && c->klass->parent_is_bds)) { + if (c == ignore) { continue; } bdrv_parent_drained_end_single(c); @@ -XXX,XX +XXX,XX @@ typedef struct { bool begin; bool poll; BdrvChild *parent; - bool ignore_bds_parents; } BdrvCoDrainData; /* Returns true if BDRV_POLL_WHILE() should go into a blocking aio_poll() */ @@ -XXX,XX +XXX,XX @@ static bool bdrv_drain_poll_top_level(BlockDriverState *bs, } static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, - bool ignore_bds_parents, bool poll); -static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, - bool ignore_bds_parents); + bool poll); +static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent); static void bdrv_co_drain_bh_cb(void *opaque) { @@ -XXX,XX +XXX,XX @@ static void bdrv_co_drain_bh_cb(void *opaque) aio_context_acquire(ctx); bdrv_dec_in_flight(bs); if (data->begin) { - bdrv_do_drained_begin(bs, data->parent, data->ignore_bds_parents, - data->poll); + bdrv_do_drained_begin(bs, data->parent, data->poll); } else { assert(!data->poll); - bdrv_do_drained_end(bs, data->parent, data->ignore_bds_parents); + bdrv_do_drained_end(bs, data->parent); } aio_context_release(ctx); } else { @@ -XXX,XX +XXX,XX @@ static void bdrv_co_drain_bh_cb(void *opaque) static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, bool begin, BdrvChild *parent, - bool ignore_bds_parents, bool poll) { BdrvCoDrainData data; @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, .done = false, .begin = begin, .parent = parent, - .ignore_bds_parents = ignore_bds_parents, .poll = poll, }; @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, } } -void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, - BdrvChild *parent, bool ignore_bds_parents) +void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) { IO_OR_GS_CODE(); assert(!qemu_in_coroutine()); @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, /* Stop things in parent-to-child order */ if (qatomic_fetch_inc(&bs->quiesce_counter) == 0) { aio_disable_external(bdrv_get_aio_context(bs)); - - /* TODO Remove ignore_bds_parents, we don't consider it any more */ - bdrv_parent_drained_begin(bs, parent, false); + bdrv_parent_drained_begin(bs, parent); if (bs->drv && bs->drv->bdrv_drain_begin) { bs->drv->bdrv_drain_begin(bs); } @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, } static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, - bool ignore_bds_parents, bool poll) + bool poll) { if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, true, parent, ignore_bds_parents, poll); + bdrv_co_yield_to_drain(bs, true, parent, poll); return; } - bdrv_do_drained_begin_quiesce(bs, parent, ignore_bds_parents); + bdrv_do_drained_begin_quiesce(bs, parent); /* * Wait for drained requests to finish. @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, * nodes. */ if (poll) { - assert(!ignore_bds_parents); BDRV_POLL_WHILE(bs, bdrv_drain_poll_top_level(bs, parent)); } } @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, void bdrv_drained_begin(BlockDriverState *bs) { IO_OR_GS_CODE(); - bdrv_do_drained_begin(bs, NULL, false, true); + bdrv_do_drained_begin(bs, NULL, true); } /** * This function does not poll, nor must any of its recursively called * functions. */ -static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, - bool ignore_bds_parents) +static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent) { int old_quiesce_counter; if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, false, parent, ignore_bds_parents, false); + bdrv_co_yield_to_drain(bs, false, parent, false); return; } assert(bs->quiesce_counter > 0); @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, if (bs->drv && bs->drv->bdrv_drain_end) { bs->drv->bdrv_drain_end(bs); } - /* TODO Remove ignore_bds_parents, we don't consider it any more */ - bdrv_parent_drained_end(bs, parent, false); - + bdrv_parent_drained_end(bs, parent); aio_enable_external(bdrv_get_aio_context(bs)); } } @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_end(BlockDriverState *bs, BdrvChild *parent, void bdrv_drained_end(BlockDriverState *bs) { IO_OR_GS_CODE(); - bdrv_do_drained_end(bs, NULL, false); + bdrv_do_drained_end(bs, NULL); } void bdrv_drain(BlockDriverState *bs) @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) GLOBAL_STATE_CODE(); if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(NULL, true, NULL, true, true); + bdrv_co_yield_to_drain(NULL, true, NULL, true); return; } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - bdrv_do_drained_begin(bs, NULL, true, false); + bdrv_do_drained_begin(bs, NULL, false); aio_context_release(aio_context); } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end_quiesce(BlockDriverState *bs) g_assert(!bs->refcnt); while (bs->quiesce_counter) { - bdrv_do_drained_end(bs, NULL, true); + bdrv_do_drained_end(bs, NULL); } } @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_end(void) AioContext *aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); - bdrv_do_drained_end(bs, NULL, true); + bdrv_do_drained_end(bs, NULL); aio_context_release(aio_context); } -- 2.38.1 The next patch adds a parent drain to bdrv_attach_child_common(), which shouldn't be, but is currently called from coroutines in some cases (e.g. .bdrv_co_create implementations generally open new nodes). Therefore, the assertion that we're not in a coroutine doesn't hold true any more. We could just remove the assertion because there is nothing in the function that should be in conflict with running in a coroutine, but just to be on the safe side, we can reverse the caller relationship between bdrv_do_drained_begin() and bdrv_do_drained_begin_quiesce() so that the latter also just drops out of coroutine context and we can still be certain in the future that any drain code doesn't run in coroutines. As a nice side effect, the structure of bdrv_do_drained_begin() is now symmetrical with bdrv_do_drained_end(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-14-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/io.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static void coroutine_fn bdrv_co_yield_to_drain(BlockDriverState *bs, } } -void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) +static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, + bool poll) { IO_OR_GS_CODE(); - assert(!qemu_in_coroutine()); + + if (qemu_in_coroutine()) { + bdrv_co_yield_to_drain(bs, true, parent, poll); + return; + } /* Stop things in parent-to-child order */ if (qatomic_fetch_inc(&bs->quiesce_counter) == 0) { @@ -XXX,XX +XXX,XX @@ void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) bs->drv->bdrv_drain_begin(bs); } } -} - -static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, - bool poll) -{ - if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(bs, true, parent, poll); - return; - } - - bdrv_do_drained_begin_quiesce(bs, parent); /* * Wait for drained requests to finish. @@ -XXX,XX +XXX,XX @@ static void bdrv_do_drained_begin(BlockDriverState *bs, BdrvChild *parent, } } +void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, BdrvChild *parent) +{ + bdrv_do_drained_begin(bs, parent, false); +} + void bdrv_drained_begin(BlockDriverState *bs) { IO_OR_GS_CODE(); -- 2.38.1 In order to make sure that bdrv_replace_child_noperm() doesn't have to poll any more, get rid of the bdrv_parent_drained_begin_single() call. This is possible now because we can require that the parent is already drained through the child in question when the function is called and we don't call the parent drain callbacks more than once. The additional drain calls needed in callers cause the test case to run its code in the drain handler too early (bdrv_attach_child() drains now), so modify it to only enable the code after the test setup has completed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-15-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 8 +++ block.c | 103 ++++++++++++++++++++++++++++++----- block/io.c | 2 +- tests/unit/test-bdrv-drain.c | 10 ++++ 4 files changed, 108 insertions(+), 15 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); */ void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); +/** + * bdrv_parent_drained_poll_single: + * + * Returns true if there is any pending activity to cease before @c can be + * called quiesced, false otherwise. + */ +bool bdrv_parent_drained_poll_single(BdrvChild *c); + /** * bdrv_parent_drained_end_single: * diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_abort(void *opaque) GLOBAL_STATE_CODE(); /* old_bs reference is transparently moved from @s to @s->child */ + if (!s->child->bs) { + /* + * The parents were undrained when removing old_bs from the child. New + * requests can't have been made, though, because the child was empty. + * + * TODO Make bdrv_replace_child_noperm() transactionable to avoid + * undraining the parent in the first place. Once this is done, having + * new_bs drained when calling bdrv_replace_child_tran() is not a + * requirement any more. + */ + bdrv_parent_drained_begin_single(s->child, false); + assert(!bdrv_parent_drained_poll_single(s->child)); + } + assert(s->child->quiesced_parent); bdrv_replace_child_noperm(s->child, s->old_bs); bdrv_unref(new_bs); } @@ -XXX,XX +XXX,XX @@ static TransactionActionDrv bdrv_replace_child_drv = { * * Note: real unref of old_bs is done only on commit. * + * Both @child->bs and @new_bs (if non-NULL) must be drained. @new_bs must be + * kept drained until the transaction is completed. + * * The function doesn't update permissions, caller is responsible for this. */ static void bdrv_replace_child_tran(BdrvChild *child, BlockDriverState *new_bs, Transaction *tran) { BdrvReplaceChildState *s = g_new(BdrvReplaceChildState, 1); + + assert(child->quiesced_parent); + assert(!new_bs || new_bs->quiesce_counter); + *s = (BdrvReplaceChildState) { .child = child, .old_bs = child->bs, @@ -XXX,XX +XXX,XX @@ uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm) return permissions[qapi_perm]; } +/* + * Replaces the node that a BdrvChild points to without updating permissions. + * + * If @new_bs is non-NULL, the parent of @child must already be drained through + * @child. + * + * This function does not poll. + */ static void bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs) { @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, int new_bs_quiesce_counter; assert(!child->frozen); + + /* + * If we want to change the BdrvChild to point to a drained node as its new + * child->bs, we need to make sure that its new parent is drained, too. In + * other words, either child->quiesce_parent must already be true or we must + * be able to set it and keep the parent's quiesce_counter consistent with + * that, but without polling or starting new requests (this function + * guarantees that it doesn't poll, and starting new requests would be + * against the invariants of drain sections). + * + * To keep things simple, we pick the first option (child->quiesce_parent + * must already be true). We also generalise the rule a bit to make it + * easier to verify in callers and more likely to be covered in test cases: + * The parent must be quiesced through this child even if new_bs isn't + * currently drained. + * + * The only exception is for callers that always pass new_bs == NULL. In + * this case, we obviously never need to consider the case of a drained + * new_bs, so we can keep the callers simpler by allowing them not to drain + * the parent. + */ + assert(!new_bs || child->quiesced_parent); assert(old_bs != new_bs); GLOBAL_STATE_CODE(); @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)); } - /* - * If the new child node is drained but the old one was not, flush - * all outstanding requests to the old child node. - */ - new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); - if (new_bs_quiesce_counter && !child->quiesced_parent) { - bdrv_parent_drained_begin_single(child, true); - } - if (old_bs) { if (child->klass->detach) { child->klass->detach(child); @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, } /* - * If the old child node was drained but the new one is not, allow - * requests to come in only after the new node has been attached. - * - * Update new_bs_quiesce_counter because bdrv_parent_drained_begin_single() - * polls, which could have changed the value. + * If the parent was drained through this BdrvChild previously, but new_bs + * is not drained, allow requests to come in only after the new node has + * been attached. */ new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); if (!new_bs_quiesce_counter && child->quiesced_parent) { @@ -XXX,XX +XXX,XX @@ static BdrvChild *bdrv_attach_child_common(BlockDriverState *child_bs, } bdrv_ref(child_bs); + /* + * Let every new BdrvChild start with a drained parent. Inserting the child + * in the graph with bdrv_replace_child_noperm() will undrain it if + * @child_bs is not drained. + * + * The child was only just created and is not yet visible in global state + * until bdrv_replace_child_noperm() inserts it into the graph, so nobody + * could have sent requests and polling is not necessary. + * + * Note that this means that the parent isn't fully drained yet, we only + * stop new requests from coming in. This is fine, we don't care about the + * old requests here, they are not for this child. If another place enters a + * drain section for the same parent, but wants it to be fully quiesced, it + * will not run most of the the code in .drained_begin() again (which is not + * a problem, we already did this), but it will still poll until the parent + * is fully quiesced, so it will not be negatively affected either. + */ + bdrv_parent_drained_begin_single(new_child, false); bdrv_replace_child_noperm(new_child, child_bs); BdrvAttachChildCommonState *s = g_new(BdrvAttachChildCommonState, 1); @@ -XXX,XX +XXX,XX @@ static void bdrv_remove_child(BdrvChild *child, Transaction *tran) } if (child->bs) { + BlockDriverState *bs = child->bs; + bdrv_drained_begin(bs); bdrv_replace_child_tran(child, NULL, tran); + bdrv_drained_end(bs); } tran_add(tran, &bdrv_remove_child_drv, child); } +static void undrain_on_clean_cb(void *opaque) +{ + bdrv_drained_end(opaque); +} + +static TransactionActionDrv undrain_on_clean = { + .clean = undrain_on_clean_cb, +}; + static int bdrv_replace_node_noperm(BlockDriverState *from, BlockDriverState *to, bool auto_skip, Transaction *tran, @@ -XXX,XX +XXX,XX @@ static int bdrv_replace_node_noperm(BlockDriverState *from, GLOBAL_STATE_CODE(); + bdrv_drained_begin(from); + bdrv_drained_begin(to); + tran_add(tran, &undrain_on_clean, from); + tran_add(tran, &undrain_on_clean, to); + QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { assert(c->bs == from); if (!should_update_child(c, to)) { diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore) } } -static bool bdrv_parent_drained_poll_single(BdrvChild *c) +bool bdrv_parent_drained_poll_single(BdrvChild *c) { if (c->klass->drained_poll) { return c->klass->drained_poll(c); diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ static void test_drop_intermediate_poll(void) typedef struct BDRVReplaceTestState { + bool setup_completed; bool was_drained; bool was_undrained; bool has_read; @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_test_drain_begin(BlockDriverState *bs) { BDRVReplaceTestState *s = bs->opaque; + if (!s->setup_completed) { + return; + } + if (!s->drain_count) { s->drain_co = qemu_coroutine_create(bdrv_replace_test_drain_co, bs); bdrv_inc_in_flight(bs); @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_test_drain_end(BlockDriverState *bs) { BDRVReplaceTestState *s = bs->opaque; + if (!s->setup_completed) { + return; + } + g_assert(s->drain_count > 0); if (!--s->drain_count) { s->was_undrained = true; @@ -XXX,XX +XXX,XX @@ static void do_test_replace_child_mid_drain(int old_drain_count, bdrv_ref(old_child_bs); bdrv_attach_child(parent_bs, old_child_bs, "child", &child_of_bds, BDRV_CHILD_COW, &error_abort); + parent_s->setup_completed = true; for (i = 0; i < old_drain_count; i++) { bdrv_drained_begin(old_child_bs); -- 2.38.1 All callers of bdrv_parent_drained_begin_single() pass poll=false now, so we don't need the parameter any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-16-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 5 ++--- block.c | 4 ++-- block/io.c | 8 ++------ 3 files changed, 6 insertions(+), 11 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); /** * bdrv_parent_drained_begin_single: * - * Begin a quiesced section for the parent of @c. If @poll is true, wait for - * any pending activity to cease. + * Begin a quiesced section for the parent of @c. */ -void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); +void bdrv_parent_drained_begin_single(BdrvChild *c); /** * bdrv_parent_drained_poll_single: diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_abort(void *opaque) * new_bs drained when calling bdrv_replace_child_tran() is not a * requirement any more. */ - bdrv_parent_drained_begin_single(s->child, false); + bdrv_parent_drained_begin_single(s->child); assert(!bdrv_parent_drained_poll_single(s->child)); } assert(s->child->quiesced_parent); @@ -XXX,XX +XXX,XX @@ static BdrvChild *bdrv_attach_child_common(BlockDriverState *child_bs, * a problem, we already did this), but it will still poll until the parent * is fully quiesced, so it will not be negatively affected either. */ - bdrv_parent_drained_begin_single(new_child, false); + bdrv_parent_drained_begin_single(new_child); bdrv_replace_child_noperm(new_child, child_bs); BdrvAttachChildCommonState *s = g_new(BdrvAttachChildCommonState, 1); diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore) if (c == ignore) { continue; } - bdrv_parent_drained_begin_single(c, false); + bdrv_parent_drained_begin_single(c); } } @@ -XXX,XX +XXX,XX @@ static bool bdrv_parent_drained_poll(BlockDriverState *bs, BdrvChild *ignore, return busy; } -void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll) +void bdrv_parent_drained_begin_single(BdrvChild *c) { - AioContext *ctx = bdrv_child_get_parent_aio_context(c); IO_OR_GS_CODE(); assert(!c->quiesced_parent); @@ -XXX,XX +XXX,XX @@ void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll) if (c->klass->drained_begin) { c->klass->drained_begin(c); } - if (poll) { - AIO_WAIT_WHILE(ctx, bdrv_parent_drained_poll_single(c)); - } } static void bdrv_merge_limits(BlockLimits *dst, const BlockLimits *src) -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> bdrv_common_block_status_above() is a g_c_w, and it is being called by many "wrapper" functions like bdrv_is_allocated(), bdrv_is_allocated_above() and bdrv_block_status_above(). Because we want to eventually split the coroutine from non-coroutine case in g_c_w, create duplicate wrappers that take care of directly calling the same coroutine functions called in the g_c_w. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-2-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-io.h | 15 +++++++++++ block/io.c | 58 +++++++++++++++++++++++++++++++++++++--- 2 files changed, 70 insertions(+), 3 deletions(-) diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); int bdrv_block_status(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file); + +int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, + BlockDriverState **file); int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file); + +int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t offset, + int64_t bytes, int64_t *pnum); int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum); + +int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, + BlockDriverState *base, + bool include_base, int64_t offset, + int64_t bytes, int64_t *pnum); int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, bool include_base, int64_t offset, int64_t bytes, int64_t *pnum); + int coroutine_fn bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, int64_t bytes); diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs, return ret; } +int coroutine_fn bdrv_co_block_status_above(BlockDriverState *bs, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, + BlockDriverState **file) +{ + IO_CODE(); + return bdrv_co_common_block_status_above(bs, base, false, true, offset, + bytes, pnum, map, file, NULL); +} + int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, int64_t offset, int64_t bytes, int64_t *pnum, int64_t *map, BlockDriverState **file) @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, return (pnum == bytes) && (ret & BDRV_BLOCK_ZERO); } +int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t offset, + int64_t bytes, int64_t *pnum) +{ + int ret; + int64_t dummy; + IO_CODE(); + + ret = bdrv_co_common_block_status_above(bs, bs, true, false, offset, + bytes, pnum ? pnum : &dummy, NULL, + NULL, NULL); + if (ret < 0) { + return ret; + } + return !!(ret & BDRV_BLOCK_ALLOCATED); +} + int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, int64_t *pnum) { @@ -XXX,XX +XXX,XX @@ int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, return !!(ret & BDRV_BLOCK_ALLOCATED); } +/* See bdrv_is_allocated_above for documentation */ +int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top, + BlockDriverState *base, + bool include_base, int64_t offset, + int64_t bytes, int64_t *pnum) +{ + int depth; + int ret; + IO_CODE(); + + ret = bdrv_co_common_block_status_above(top, base, include_base, false, + offset, bytes, pnum, NULL, NULL, + &depth); + if (ret < 0) { + return ret; + } + + if (ret & BDRV_BLOCK_ALLOCATED) { + return depth; + } + return 0; +} + /* * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP] * @@ -XXX,XX +XXX,XX @@ int bdrv_is_allocated_above(BlockDriverState *top, int64_t bytes, int64_t *pnum) { int depth; - int ret = bdrv_common_block_status_above(top, base, include_base, false, - offset, bytes, pnum, NULL, NULL, - &depth); + int ret; IO_CODE(); + + ret = bdrv_common_block_status_above(top, base, include_base, false, + offset, bytes, pnum, NULL, NULL, + &depth); if (ret < 0) { return ret; } -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> These functions end up calling bdrv_common_block_status_above(), a generated_co_wrapper function. In addition, they also happen to be always called in coroutine context, meaning all callers are coroutine_fn. This means that the g_c_w function will enter the qemu_in_coroutine() case and eventually suspend (or in other words call qemu_coroutine_yield()). Therefore we can mark such functions coroutine_fn too. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-3-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-copy.h | 5 +++-- block/block-copy.c | 21 ++++++++++++--------- 2 files changed, 15 insertions(+), 11 deletions(-) diff --git a/include/block/block-copy.h b/include/block/block-copy.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-copy.h +++ b/include/block/block-copy.h @@ -XXX,XX +XXX,XX @@ void block_copy_set_progress_meter(BlockCopyState *s, ProgressMeter *pm); void block_copy_state_free(BlockCopyState *s); void block_copy_reset(BlockCopyState *s, int64_t offset, int64_t bytes); -int64_t block_copy_reset_unallocated(BlockCopyState *s, - int64_t offset, int64_t *count); +int64_t coroutine_fn block_copy_reset_unallocated(BlockCopyState *s, + int64_t offset, + int64_t *count); int coroutine_fn block_copy(BlockCopyState *s, int64_t offset, int64_t bytes, bool ignore_ratelimit, uint64_t timeout_ns, diff --git a/block/block-copy.c b/block/block-copy.c index XXXXXXX..XXXXXXX 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -XXX,XX +XXX,XX @@ static coroutine_fn int block_copy_task_entry(AioTask *task) return ret; } -static int block_copy_block_status(BlockCopyState *s, int64_t offset, - int64_t bytes, int64_t *pnum) +static coroutine_fn int block_copy_block_status(BlockCopyState *s, + int64_t offset, + int64_t bytes, int64_t *pnum) { int64_t num; BlockDriverState *base; @@ -XXX,XX +XXX,XX @@ static int block_copy_block_status(BlockCopyState *s, int64_t offset, base = NULL; } - ret = bdrv_block_status_above(s->source->bs, base, offset, bytes, &num, - NULL, NULL); + ret = bdrv_co_block_status_above(s->source->bs, base, offset, bytes, &num, + NULL, NULL); if (ret < 0 || num < s->cluster_size) { /* * On error or if failed to obtain large enough chunk just fallback to @@ -XXX,XX +XXX,XX @@ static int block_copy_block_status(BlockCopyState *s, int64_t offset, * Check if the cluster starting at offset is allocated or not. * return via pnum the number of contiguous clusters sharing this allocation. */ -static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset, - int64_t *pnum) +static int coroutine_fn block_copy_is_cluster_allocated(BlockCopyState *s, + int64_t offset, + int64_t *pnum) { BlockDriverState *bs = s->source->bs; int64_t count, total_count = 0; @@ -XXX,XX +XXX,XX @@ static int block_copy_is_cluster_allocated(BlockCopyState *s, int64_t offset, assert(QEMU_IS_ALIGNED(offset, s->cluster_size)); while (true) { - ret = bdrv_is_allocated(bs, offset, bytes, &count); + ret = bdrv_co_is_allocated(bs, offset, bytes, &count); if (ret < 0) { return ret; } @@ -XXX,XX +XXX,XX @@ void block_copy_reset(BlockCopyState *s, int64_t offset, int64_t bytes) * @return 0 when the cluster at @offset was unallocated, * 1 otherwise, and -ret on error. */ -int64_t block_copy_reset_unallocated(BlockCopyState *s, - int64_t offset, int64_t *count) +int64_t coroutine_fn block_copy_reset_unallocated(BlockCopyState *s, + int64_t offset, + int64_t *count) { int ret; int64_t clusters, bytes; -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> These functions end up calling bdrv_*() implemented as generated_co_wrapper functions. In addition, they also happen to be always called in coroutine context, meaning all callers are coroutine_fn. This means that the g_c_w function will enter the qemu_in_coroutine() case and eventually suspend (or in other words call qemu_coroutine_yield()). Therefore we can mark such functions coroutine_fn too. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-4-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- nbd/server.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index XXXXXXX..XXXXXXX 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -XXX,XX +XXX,XX @@ static int nbd_extent_array_add(NBDExtentArray *ea, return 0; } -static int blockstatus_to_extents(BlockDriverState *bs, uint64_t offset, - uint64_t bytes, NBDExtentArray *ea) +static int coroutine_fn blockstatus_to_extents(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + NBDExtentArray *ea) { while (bytes) { uint32_t flags; int64_t num; - int ret = bdrv_block_status_above(bs, NULL, offset, bytes, &num, - NULL, NULL); + int ret = bdrv_co_block_status_above(bs, NULL, offset, bytes, &num, + NULL, NULL); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int blockstatus_to_extents(BlockDriverState *bs, uint64_t offset, return 0; } -static int blockalloc_to_extents(BlockDriverState *bs, uint64_t offset, - uint64_t bytes, NBDExtentArray *ea) +static int coroutine_fn blockalloc_to_extents(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, + NBDExtentArray *ea) { while (bytes) { int64_t num; - int ret = bdrv_is_allocated_above(bs, NULL, false, offset, bytes, - &num); + int ret = bdrv_co_is_allocated_above(bs, NULL, false, offset, bytes, + &num); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int nbd_co_send_extents(NBDClient *client, uint64_t handle, } /* Get block status from the exported device and send it to the client */ -static int nbd_co_send_block_status(NBDClient *client, uint64_t handle, - BlockDriverState *bs, uint64_t offset, - uint32_t length, bool dont_fragment, - bool last, uint32_t context_id, - Error **errp) +static int +coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle, + BlockDriverState *bs, uint64_t offset, + uint32_t length, bool dont_fragment, + bool last, uint32_t context_id, + Error **errp) { int ret; unsigned int nb_extents = dont_fragment ? 1 : NBD_MAX_BLOCK_STATUS_EXTENTS; -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Avoid mixing bdrv_* functions with blk_*, so create blk_* counterparts for bdrv_block_status_above and bdrv_is_allocated_above. Note that since blk_co_block_status_above only calls the g_c_w function bdrv_common_block_status_above and is marked as coroutine_fn, call directly bdrv_co_common_block_status_above() to avoid using a g_c_w. Same applies to blk_co_is_allocated_above. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-5-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/sysemu/block-backend-io.h | 9 +++++++++ block/block-backend.c | 21 ++++++++++++++++++++ block/commit.c | 4 ++-- nbd/server.c | 32 +++++++++++++++---------------- 4 files changed, 48 insertions(+), 18 deletions(-) diff --git a/include/sysemu/block-backend-io.h b/include/sysemu/block-backend-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/sysemu/block-backend-io.h +++ b/include/sysemu/block-backend-io.h @@ -XXX,XX +XXX,XX @@ int coroutine_fn blk_co_copy_range(BlockBackend *blk_in, int64_t off_in, int64_t bytes, BdrvRequestFlags read_flags, BdrvRequestFlags write_flags); +int coroutine_fn blk_co_block_status_above(BlockBackend *blk, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, + BlockDriverState **file); +int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk, + BlockDriverState *base, + bool include_base, int64_t offset, + int64_t bytes, int64_t *pnum); /* * "I/O or GS" API functions. These functions can run without diff --git a/block/block-backend.c b/block/block-backend.c index XXXXXXX..XXXXXXX 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -XXX,XX +XXX,XX @@ int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, return blk_co_pwritev_part(blk, offset, bytes, qiov, 0, flags); } +int coroutine_fn blk_co_block_status_above(BlockBackend *blk, + BlockDriverState *base, + int64_t offset, int64_t bytes, + int64_t *pnum, int64_t *map, + BlockDriverState **file) +{ + IO_CODE(); + return bdrv_co_block_status_above(blk_bs(blk), base, offset, bytes, pnum, + map, file); +} + +int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk, + BlockDriverState *base, + bool include_base, int64_t offset, + int64_t bytes, int64_t *pnum) +{ + IO_CODE(); + return bdrv_co_is_allocated_above(blk_bs(blk), base, include_base, offset, + bytes, pnum); +} + typedef struct BlkRwCo { BlockBackend *blk; int64_t offset; diff --git a/block/commit.c b/block/commit.c index XXXXXXX..XXXXXXX 100644 --- a/block/commit.c +++ b/block/commit.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn commit_run(Job *job, Error **errp) break; } /* Copy if allocated above the base */ - ret = bdrv_is_allocated_above(blk_bs(s->top), s->base_overlay, true, - offset, COMMIT_BUFFER_SIZE, &n); + ret = blk_co_is_allocated_above(s->top, s->base_overlay, true, + offset, COMMIT_BUFFER_SIZE, &n); copy = (ret > 0); trace_commit_one_iteration(s, offset, n, ret); if (copy) { diff --git a/nbd/server.c b/nbd/server.c index XXXXXXX..XXXXXXX 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn nbd_co_send_structured_error(NBDClient *client, } /* Do a sparse read and send the structured reply to the client. - * Returns -errno if sending fails. bdrv_block_status_above() failure is + * Returns -errno if sending fails. blk_co_block_status_above() failure is * reported to the client, at which point this function succeeds. */ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client, @@ -XXX,XX +XXX,XX @@ static int coroutine_fn nbd_co_send_sparse_read(NBDClient *client, while (progress < size) { int64_t pnum; - int status = bdrv_block_status_above(blk_bs(exp->common.blk), NULL, - offset + progress, - size - progress, &pnum, NULL, - NULL); + int status = blk_co_block_status_above(exp->common.blk, NULL, + offset + progress, + size - progress, &pnum, NULL, + NULL); bool final; if (status < 0) { @@ -XXX,XX +XXX,XX @@ static int nbd_extent_array_add(NBDExtentArray *ea, return 0; } -static int coroutine_fn blockstatus_to_extents(BlockDriverState *bs, +static int coroutine_fn blockstatus_to_extents(BlockBackend *blk, uint64_t offset, uint64_t bytes, NBDExtentArray *ea) { while (bytes) { uint32_t flags; int64_t num; - int ret = bdrv_co_block_status_above(bs, NULL, offset, bytes, &num, - NULL, NULL); + int ret = blk_co_block_status_above(blk, NULL, offset, bytes, &num, + NULL, NULL); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn blockstatus_to_extents(BlockDriverState *bs, return 0; } -static int coroutine_fn blockalloc_to_extents(BlockDriverState *bs, +static int coroutine_fn blockalloc_to_extents(BlockBackend *blk, uint64_t offset, uint64_t bytes, NBDExtentArray *ea) { while (bytes) { int64_t num; - int ret = bdrv_co_is_allocated_above(bs, NULL, false, offset, bytes, - &num); + int ret = blk_co_is_allocated_above(blk, NULL, false, offset, bytes, + &num); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int nbd_co_send_extents(NBDClient *client, uint64_t handle, /* Get block status from the exported device and send it to the client */ static int coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle, - BlockDriverState *bs, uint64_t offset, + BlockBackend *blk, uint64_t offset, uint32_t length, bool dont_fragment, bool last, uint32_t context_id, Error **errp) @@ -XXX,XX +XXX,XX @@ coroutine_fn nbd_co_send_block_status(NBDClient *client, uint64_t handle, g_autoptr(NBDExtentArray) ea = nbd_extent_array_new(nb_extents); if (context_id == NBD_META_ID_BASE_ALLOCATION) { - ret = blockstatus_to_extents(bs, offset, length, ea); + ret = blockstatus_to_extents(blk, offset, length, ea); } else { - ret = blockalloc_to_extents(bs, offset, length, ea); + ret = blockalloc_to_extents(blk, offset, length, ea); } if (ret < 0) { return nbd_co_send_structured_error( @@ -XXX,XX +XXX,XX @@ static coroutine_fn int nbd_handle_request(NBDClient *client, if (client->export_meta.base_allocation) { ret = nbd_co_send_block_status(client, request->handle, - blk_bs(exp->common.blk), + exp->common.blk, request->from, request->len, dont_fragment, !--contexts_remaining, @@ -XXX,XX +XXX,XX @@ static coroutine_fn int nbd_handle_request(NBDClient *client, if (client->export_meta.allocation_depth) { ret = nbd_co_send_block_status(client, request->handle, - blk_bs(exp->common.blk), + exp->common.blk, request->from, request->len, dont_fragment, !--contexts_remaining, -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> These functions end up calling bdrv_create() implemented as generated_co_wrapper functions. In addition, they also happen to be always called in coroutine context, meaning all callers are coroutine_fn. This means that the g_c_w function will enter the qemu_in_coroutine() case and eventually suspend (or in other words call qemu_coroutine_yield()). Therefore we can mark such functions coroutine_fn too. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-6-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index XXXXXXX..XXXXXXX 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -XXX,XX +XXX,XX @@ exit: return ret; } -static int vmdk_create_extent(const char *filename, int64_t filesize, - bool flat, bool compress, bool zeroed_grain, - BlockBackend **pbb, - QemuOpts *opts, Error **errp) +static int coroutine_fn vmdk_create_extent(const char *filename, + int64_t filesize, bool flat, + bool compress, bool zeroed_grain, + BlockBackend **pbb, + QemuOpts *opts, Error **errp) { int ret; BlockBackend *blk = NULL; @@ -XXX,XX +XXX,XX @@ static int filename_decompose(const char *filename, char *path, char *prefix, * non-split format. * idx >= 1: get the n-th extent if in a split subformat */ -typedef BlockBackend *(*vmdk_create_extent_fn)(int64_t size, - int idx, - bool flat, - bool split, - bool compress, - bool zeroed_grain, - void *opaque, - Error **errp); +typedef BlockBackend * coroutine_fn (*vmdk_create_extent_fn)(int64_t size, + int idx, + bool flat, + bool split, + bool compress, + bool zeroed_grain, + void *opaque, + Error **errp); static void vmdk_desc_add_extent(GString *desc, const char *extent_line_fmt, @@ -XXX,XX +XXX,XX @@ typedef struct { QemuOpts *opts; } VMDKCreateOptsData; -static BlockBackend *vmdk_co_create_opts_cb(int64_t size, int idx, +static BlockBackend * coroutine_fn vmdk_co_create_opts_cb(int64_t size, int idx, bool flat, bool split, bool compress, bool zeroed_grain, void *opaque, Error **errp) @@ -XXX,XX +XXX,XX @@ exit: return ret; } -static BlockBackend *vmdk_co_create_cb(int64_t size, int idx, - bool flat, bool split, bool compress, - bool zeroed_grain, void *opaque, - Error **errp) +static BlockBackend * coroutine_fn vmdk_co_create_cb(int64_t size, int idx, + bool flat, bool split, + bool compress, + bool zeroed_grain, + void *opaque, Error **errp) { int ret; BlockDriverState *bs; -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> We know that the string will stay around until the function returns, and the parameter of drv->bdrv_co_create_opts is const char*, so it must not be modified either. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-7-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int bdrv_create(BlockDriver *drv, const char* filename, Coroutine *co; CreateCo cco = { .drv = drv, - .filename = g_strdup(filename), + .filename = filename, .opts = opts, .ret = NOT_DONE, .err = NULL, @@ -XXX,XX +XXX,XX @@ int bdrv_create(BlockDriver *drv, const char* filename, if (!drv->bdrv_co_create_opts) { error_setg(errp, "Driver '%s' does not support image creation", drv->format_name); - ret = -ENOTSUP; - goto out; + return -ENOTSUP; } if (qemu_in_coroutine()) { @@ -XXX,XX +XXX,XX @@ int bdrv_create(BlockDriver *drv, const char* filename, } } -out: - g_free(cco.filename); return ret; } -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Call two different functions depending on whether bdrv_create is in coroutine or not, following the same pattern as generated_co_wrapper functions. This allows to also call the coroutine function directly, without using CreateCo or relying in bdrv_create(). Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-8-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 69 ++++++++++++++++++++++++++++----------------------------- 1 file changed, 34 insertions(+), 35 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ typedef struct CreateCo { Error *err; } CreateCo; -static void coroutine_fn bdrv_create_co_entry(void *opaque) +static int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, + QemuOpts *opts, Error **errp) { - Error *local_err = NULL; int ret; + GLOBAL_STATE_CODE(); + ERRP_GUARD(); + if (!drv->bdrv_co_create_opts) { + error_setg(errp, "Driver '%s' does not support image creation", + drv->format_name); + return -ENOTSUP; + } + + ret = drv->bdrv_co_create_opts(drv, filename, opts, errp); + if (ret < 0 && !*errp) { + error_setg_errno(errp, -ret, "Could not create image"); + } + + return ret; +} + +static void coroutine_fn bdrv_create_co_entry(void *opaque) +{ CreateCo *cco = opaque; - assert(cco->drv); GLOBAL_STATE_CODE(); - ret = cco->drv->bdrv_co_create_opts(cco->drv, - cco->filename, cco->opts, &local_err); - error_propagate(&cco->err, local_err); - cco->ret = ret; + cco->ret = bdrv_co_create(cco->drv, cco->filename, cco->opts, &cco->err); + aio_wait_kick(); } int bdrv_create(BlockDriver *drv, const char* filename, QemuOpts *opts, Error **errp) { - int ret; - GLOBAL_STATE_CODE(); - Coroutine *co; - CreateCo cco = { - .drv = drv, - .filename = filename, - .opts = opts, - .ret = NOT_DONE, - .err = NULL, - }; - - if (!drv->bdrv_co_create_opts) { - error_setg(errp, "Driver '%s' does not support image creation", drv->format_name); - return -ENOTSUP; - } - if (qemu_in_coroutine()) { /* Fast-path if already in coroutine context */ - bdrv_create_co_entry(&cco); + return bdrv_co_create(drv, filename, opts, errp); } else { + Coroutine *co; + CreateCo cco = { + .drv = drv, + .filename = filename, + .opts = opts, + .ret = NOT_DONE, + .err = NULL, + }; + co = qemu_coroutine_create(bdrv_create_co_entry, &cco); qemu_coroutine_enter(co); while (cco.ret == NOT_DONE) { aio_poll(qemu_get_aio_context(), true); } + error_propagate(errp, cco.err); + return cco.ret; } - - ret = cco.ret; - if (ret < 0) { - if (cco.err) { - error_propagate(errp, cco.err); - } else { - error_setg_errno(errp, -ret, "Could not create image"); - } - } - - return ret; } /** -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> It is always called in coroutine_fn callbacks, therefore it can directly call bdrv_co_create(). Rename it to bdrv_co_create_file too. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-9-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-global-state.h | 3 ++- block.c | 5 +++-- block/crypto.c | 2 +- block/parallels.c | 2 +- block/qcow.c | 2 +- block/qcow2.c | 4 ++-- block/qed.c | 2 +- block/raw-format.c | 2 +- block/vdi.c | 2 +- block/vhdx.c | 2 +- block/vmdk.c | 2 +- block/vpc.c | 2 +- 12 files changed, 16 insertions(+), 14 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -XXX,XX +XXX,XX @@ BlockDriver *bdrv_find_protocol(const char *filename, BlockDriver *bdrv_find_format(const char *format_name); int bdrv_create(BlockDriver *drv, const char* filename, QemuOpts *opts, Error **errp); -int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); +int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts, + Error **errp); BlockDriverState *bdrv_new(void); int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ out: return ret; } -int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp) +int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts, + Error **errp) { QemuOpts *protocol_opts; BlockDriver *drv; @@ -XXX,XX +XXX,XX @@ int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp) goto out; } - ret = bdrv_create(drv, filename, protocol_opts, errp); + ret = bdrv_co_create(drv, filename, protocol_opts, errp); out: qemu_opts_del(protocol_opts); qobject_unref(qdict); diff --git a/block/crypto.c b/block/crypto.c index XXXXXXX..XXXXXXX 100644 --- a/block/crypto.c +++ b/block/crypto.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn block_crypto_co_create_opts_luks(BlockDriver *drv, } /* Create protocol layer */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto fail; } diff --git a/block/parallels.c b/block/parallels.c index XXXXXXX..XXXXXXX 100644 --- a/block/parallels.c +++ b/block/parallels.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn parallels_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto done; } diff --git a/block/qcow.c b/block/qcow.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow.c +++ b/block/qcow.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto fail; } diff --git a/block/qcow2.c b/block/qcow2.c index XXXXXXX..XXXXXXX 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto finish; } @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv, /* Create and open an external data file (protocol layer) */ val = qdict_get_try_str(qdict, BLOCK_OPT_DATA_FILE); if (val) { - ret = bdrv_create_file(val, opts, errp); + ret = bdrv_co_create_file(val, opts, errp); if (ret < 0) { goto finish; } diff --git a/block/qed.c b/block/qed.c index XXXXXXX..XXXXXXX 100644 --- a/block/qed.c +++ b/block/qed.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_qed_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto fail; } diff --git a/block/raw-format.c b/block/raw-format.c index XXXXXXX..XXXXXXX 100644 --- a/block/raw-format.c +++ b/block/raw-format.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn raw_co_create_opts(BlockDriver *drv, QemuOpts *opts, Error **errp) { - return bdrv_create_file(filename, opts, errp); + return bdrv_co_create_file(filename, opts, errp); } static int raw_open(BlockDriverState *bs, QDict *options, int flags, diff --git a/block/vdi.c b/block/vdi.c index XXXXXXX..XXXXXXX 100644 --- a/block/vdi.c +++ b/block/vdi.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn vdi_co_create_opts(BlockDriver *drv, qdict = qemu_opts_to_qdict_filtered(opts, NULL, &vdi_create_opts, true); /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto done; } diff --git a/block/vhdx.c b/block/vhdx.c index XXXXXXX..XXXXXXX 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn vhdx_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto fail; } diff --git a/block/vmdk.c b/block/vmdk.c index XXXXXXX..XXXXXXX 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn vmdk_create_extent(const char *filename, int ret; BlockBackend *blk = NULL; - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto exit; } diff --git a/block/vpc.c b/block/vpc.c index XXXXXXX..XXXXXXX 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -XXX,XX +XXX,XX @@ static int coroutine_fn vpc_co_create_opts(BlockDriver *drv, } /* Create and open the file (protocol layer) */ - ret = bdrv_create_file(filename, opts, errp); + ret = bdrv_co_create_file(filename, opts, errp); if (ret < 0) { goto fail; } -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> In preparation to the incoming new function specifiers, rename g_c_w with a more meaningful name and document it. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-10-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- docs/devel/block-coroutine-wrapper.rst | 6 +-- block/coroutines.h | 4 +- include/block/block-common.h | 11 +++-- include/block/block-io.h | 44 ++++++++--------- include/sysemu/block-backend-io.h | 68 +++++++++++++------------- scripts/block-coroutine-wrapper.py | 6 +-- 6 files changed, 71 insertions(+), 68 deletions(-) diff --git a/docs/devel/block-coroutine-wrapper.rst b/docs/devel/block-coroutine-wrapper.rst index XXXXXXX..XXXXXXX 100644 --- a/docs/devel/block-coroutine-wrapper.rst +++ b/docs/devel/block-coroutine-wrapper.rst @@ -XXX,XX +XXX,XX @@ called ``bdrv_foo(<same args>)``. In this case the script can help. To trigger the generation: 1. You need ``bdrv_foo`` declaration somewhere (for example, in - ``block/coroutines.h``) with the ``generated_co_wrapper`` mark, + ``block/coroutines.h``) with the ``co_wrapper_mixed`` mark, like this: .. code-block:: c - int generated_co_wrapper bdrv_foo(<some args>); + int co_wrapper_mixed bdrv_foo(<some args>); 2. You need to feed this declaration to block-coroutine-wrapper script. For this, add the .h (or .c) file with the declaration to the @@ -XXX,XX +XXX,XX @@ Links 1. The script location is ``scripts/block-coroutine-wrapper.py``. -2. Generic place for private ``generated_co_wrapper`` declarations is +2. Generic place for private ``co_wrapper_mixed`` declarations is ``block/coroutines.h``, for public declarations: ``include/block/block.h`` diff --git a/block/coroutines.h b/block/coroutines.h index XXXXXXX..XXXXXXX 100644 --- a/block/coroutines.h +++ b/block/coroutines.h @@ -XXX,XX +XXX,XX @@ nbd_co_do_establish_connection(BlockDriverState *bs, bool blocking, * the "I/O or GS" API. */ -int generated_co_wrapper +int co_wrapper_mixed bdrv_common_block_status_above(BlockDriverState *bs, BlockDriverState *base, bool include_base, @@ -XXX,XX +XXX,XX @@ bdrv_common_block_status_above(BlockDriverState *bs, int64_t *map, BlockDriverState **file, int *depth); -int generated_co_wrapper +int co_wrapper_mixed nbd_do_establish_connection(BlockDriverState *bs, bool blocking, Error **errp); #endif /* BLOCK_COROUTINES_H */ diff --git a/include/block/block-common.h b/include/block/block-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -XXX,XX +XXX,XX @@ #include "qemu/transactions.h" /* - * generated_co_wrapper + * co_wrapper{*}: Function specifiers used by block-coroutine-wrapper.py * - * Function specifier, which does nothing but mark functions to be + * Function specifiers, which do nothing but mark functions to be * generated by scripts/block-coroutine-wrapper.py * - * Read more in docs/devel/block-coroutine-wrapper.rst + * Usage: read docs/devel/block-coroutine-wrapper.rst + * + * co_wrapper_mixed functions can be called by both coroutine and + * non-coroutine context. */ -#define generated_co_wrapper +#define co_wrapper_mixed /* block.c */ typedef struct BlockDriver BlockDriver; diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ * to catch when they are accidentally called by the wrong API. */ -int generated_co_wrapper bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, - int64_t bytes, - BdrvRequestFlags flags); +int co_wrapper_mixed bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, + int64_t bytes, + BdrvRequestFlags flags); int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); -int generated_co_wrapper bdrv_pread(BdrvChild *child, int64_t offset, - int64_t bytes, void *buf, - BdrvRequestFlags flags); -int generated_co_wrapper bdrv_pwrite(BdrvChild *child, int64_t offset, - int64_t bytes, const void *buf, - BdrvRequestFlags flags); -int generated_co_wrapper bdrv_pwrite_sync(BdrvChild *child, int64_t offset, - int64_t bytes, const void *buf, - BdrvRequestFlags flags); +int co_wrapper_mixed bdrv_pread(BdrvChild *child, int64_t offset, + int64_t bytes, void *buf, + BdrvRequestFlags flags); +int co_wrapper_mixed bdrv_pwrite(BdrvChild *child, int64_t offset, + int64_t bytes, const void *buf, + BdrvRequestFlags flags); +int co_wrapper_mixed bdrv_pwrite_sync(BdrvChild *child, int64_t offset, + int64_t bytes, const void *buf, + BdrvRequestFlags flags); int coroutine_fn bdrv_co_pwrite_sync(BdrvChild *child, int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags); @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_copy_range(BdrvChild *src, int64_t src_offset, void bdrv_drain(BlockDriverState *bs); -int generated_co_wrapper +int co_wrapper_mixed bdrv_truncate(BdrvChild *child, int64_t offset, bool exact, PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); -int generated_co_wrapper bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, - BdrvCheckMode fix); +int co_wrapper_mixed bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, + BdrvCheckMode fix); /* Invalidate any cached metadata used by image formats */ -int generated_co_wrapper bdrv_invalidate_cache(BlockDriverState *bs, - Error **errp); -int generated_co_wrapper bdrv_flush(BlockDriverState *bs); -int generated_co_wrapper bdrv_pdiscard(BdrvChild *child, int64_t offset, - int64_t bytes); -int generated_co_wrapper +int co_wrapper_mixed bdrv_invalidate_cache(BlockDriverState *bs, + Error **errp); +int co_wrapper_mixed bdrv_flush(BlockDriverState *bs); +int co_wrapper_mixed bdrv_pdiscard(BdrvChild *child, int64_t offset, + int64_t bytes); +int co_wrapper_mixed bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); -int generated_co_wrapper +int co_wrapper_mixed bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); /** diff --git a/include/sysemu/block-backend-io.h b/include/sysemu/block-backend-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/sysemu/block-backend-io.h +++ b/include/sysemu/block-backend-io.h @@ -XXX,XX +XXX,XX @@ int coroutine_fn blk_co_is_allocated_above(BlockBackend *blk, * the "I/O or GS" API. */ -int generated_co_wrapper blk_pread(BlockBackend *blk, int64_t offset, - int64_t bytes, void *buf, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_pread(BlockBackend *blk, int64_t offset, + int64_t bytes, void *buf, + BdrvRequestFlags flags); int coroutine_fn blk_co_pread(BlockBackend *blk, int64_t offset, int64_t bytes, void *buf, BdrvRequestFlags flags); -int generated_co_wrapper blk_preadv(BlockBackend *blk, int64_t offset, - int64_t bytes, QEMUIOVector *qiov, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_preadv(BlockBackend *blk, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags); int coroutine_fn blk_co_preadv(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags); -int generated_co_wrapper blk_preadv_part(BlockBackend *blk, int64_t offset, - int64_t bytes, QEMUIOVector *qiov, - size_t qiov_offset, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_preadv_part(BlockBackend *blk, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, + size_t qiov_offset, + BdrvRequestFlags flags); int coroutine_fn blk_co_preadv_part(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags); -int generated_co_wrapper blk_pwrite(BlockBackend *blk, int64_t offset, - int64_t bytes, const void *buf, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_pwrite(BlockBackend *blk, int64_t offset, + int64_t bytes, const void *buf, + BdrvRequestFlags flags); int coroutine_fn blk_co_pwrite(BlockBackend *blk, int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags); -int generated_co_wrapper blk_pwritev(BlockBackend *blk, int64_t offset, - int64_t bytes, QEMUIOVector *qiov, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_pwritev(BlockBackend *blk, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, + BdrvRequestFlags flags); int coroutine_fn blk_co_pwritev(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, BdrvRequestFlags flags); -int generated_co_wrapper blk_pwritev_part(BlockBackend *blk, int64_t offset, - int64_t bytes, QEMUIOVector *qiov, - size_t qiov_offset, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_pwritev_part(BlockBackend *blk, int64_t offset, + int64_t bytes, QEMUIOVector *qiov, + size_t qiov_offset, + BdrvRequestFlags flags); int coroutine_fn blk_co_pwritev_part(BlockBackend *blk, int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags); -int generated_co_wrapper blk_pwrite_compressed(BlockBackend *blk, - int64_t offset, int64_t bytes, - const void *buf); +int co_wrapper_mixed blk_pwrite_compressed(BlockBackend *blk, + int64_t offset, int64_t bytes, + const void *buf); int coroutine_fn blk_co_pwrite_compressed(BlockBackend *blk, int64_t offset, int64_t bytes, const void *buf); -int generated_co_wrapper blk_pwrite_zeroes(BlockBackend *blk, int64_t offset, - int64_t bytes, - BdrvRequestFlags flags); +int co_wrapper_mixed blk_pwrite_zeroes(BlockBackend *blk, int64_t offset, + int64_t bytes, + BdrvRequestFlags flags); int coroutine_fn blk_co_pwrite_zeroes(BlockBackend *blk, int64_t offset, int64_t bytes, BdrvRequestFlags flags); -int generated_co_wrapper blk_pdiscard(BlockBackend *blk, int64_t offset, - int64_t bytes); +int co_wrapper_mixed blk_pdiscard(BlockBackend *blk, int64_t offset, + int64_t bytes); int coroutine_fn blk_co_pdiscard(BlockBackend *blk, int64_t offset, int64_t bytes); -int generated_co_wrapper blk_flush(BlockBackend *blk); +int co_wrapper_mixed blk_flush(BlockBackend *blk); int coroutine_fn blk_co_flush(BlockBackend *blk); -int generated_co_wrapper blk_ioctl(BlockBackend *blk, unsigned long int req, - void *buf); +int co_wrapper_mixed blk_ioctl(BlockBackend *blk, unsigned long int req, + void *buf); int coroutine_fn blk_co_ioctl(BlockBackend *blk, unsigned long int req, void *buf); -int generated_co_wrapper blk_truncate(BlockBackend *blk, int64_t offset, - bool exact, PreallocMode prealloc, - BdrvRequestFlags flags, Error **errp); +int co_wrapper_mixed blk_truncate(BlockBackend *blk, int64_t offset, + bool exact, PreallocMode prealloc, + BdrvRequestFlags flags, Error **errp); int coroutine_fn blk_co_truncate(BlockBackend *blk, int64_t offset, bool exact, PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index XXXXXXX..XXXXXXX 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -XXX,XX +XXX,XX @@ """Generate coroutine wrappers for block subsystem. The program parses one or several concatenated c files from stdin, -searches for functions with the 'generated_co_wrapper' specifier +searches for functions with the 'co_wrapper_mixed' specifier and generates corresponding wrappers on stdout. Usage: block-coroutine-wrapper.py generated-file.c FILE.[ch]... @@ -XXX,XX +XXX,XX @@ def gen_block(self, format: str) -> str: return '\n'.join(format.format_map(arg.__dict__) for arg in self.args) -# Match wrappers declared with a generated_co_wrapper mark -func_decl_re = re.compile(r'^int\s*generated_co_wrapper\s*' +# Match wrappers declared with a co_wrapper_mixed mark +func_decl_re = re.compile(r'^int\s*co_wrapper_mixed\s*' r'(?P<wrapper_name>[a-z][a-z0-9_]*)' r'\((?P<args>[^)]*)\);$', re.MULTILINE) -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> This new annotation starts just a function wrapper that creates a new coroutine. It assumes the caller is not a coroutine. It will be the default annotation to be used in the future. This is much better as c_w_mixed, because it is clear if the caller is a coroutine or not, and provides the advantage of automating the code creation. In the future all c_w_mixed functions will be substituted by co_wrapper. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-11-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- docs/devel/block-coroutine-wrapper.rst | 6 +- include/block/block-common.h | 8 +- scripts/block-coroutine-wrapper.py | 110 +++++++++++++++++-------- 3 files changed, 86 insertions(+), 38 deletions(-) diff --git a/docs/devel/block-coroutine-wrapper.rst b/docs/devel/block-coroutine-wrapper.rst index XXXXXXX..XXXXXXX 100644 --- a/docs/devel/block-coroutine-wrapper.rst +++ b/docs/devel/block-coroutine-wrapper.rst @@ -XXX,XX +XXX,XX @@ called ``bdrv_foo(<same args>)``. In this case the script can help. To trigger the generation: 1. You need ``bdrv_foo`` declaration somewhere (for example, in - ``block/coroutines.h``) with the ``co_wrapper_mixed`` mark, + ``block/coroutines.h``) with the ``co_wrapper`` mark, like this: .. code-block:: c - int co_wrapper_mixed bdrv_foo(<some args>); + int co_wrapper bdrv_foo(<some args>); 2. You need to feed this declaration to block-coroutine-wrapper script. For this, add the .h (or .c) file with the declaration to the @@ -XXX,XX +XXX,XX @@ Links 1. The script location is ``scripts/block-coroutine-wrapper.py``. -2. Generic place for private ``co_wrapper_mixed`` declarations is +2. Generic place for private ``co_wrapper`` declarations is ``block/coroutines.h``, for public declarations: ``include/block/block.h`` diff --git a/include/block/block-common.h b/include/block/block-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -XXX,XX +XXX,XX @@ * * Usage: read docs/devel/block-coroutine-wrapper.rst * - * co_wrapper_mixed functions can be called by both coroutine and - * non-coroutine context. + * There are 2 kind of specifiers: + * - co_wrapper functions can be called by only non-coroutine context, because + * they always generate a new coroutine. + * - co_wrapper_mixed functions can be called by both coroutine and + * non-coroutine context. */ +#define co_wrapper #define co_wrapper_mixed /* block.c */ diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index XXXXXXX..XXXXXXX 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -XXX,XX +XXX,XX @@ """Generate coroutine wrappers for block subsystem. The program parses one or several concatenated c files from stdin, -searches for functions with the 'co_wrapper_mixed' specifier +searches for functions with the 'co_wrapper' specifier and generates corresponding wrappers on stdout. Usage: block-coroutine-wrapper.py generated-file.c FILE.[ch]... @@ -XXX,XX +XXX,XX @@ def __init__(self, param_decl: str) -> None: class FuncDecl: - def __init__(self, return_type: str, name: str, args: str) -> None: + def __init__(self, return_type: str, name: str, args: str, + variant: str) -> None: self.return_type = return_type.strip() self.name = name.strip() + self.struct_name = snake_to_camel(self.name) self.args = [ParamDecl(arg.strip()) for arg in args.split(',')] + self.create_only_co = 'mixed' not in variant + + subsystem, subname = self.name.split('_', 1) + self.co_name = f'{subsystem}_co_{subname}' + + t = self.args[0].type + if t == 'BlockDriverState *': + bs = 'bs' + elif t == 'BdrvChild *': + bs = 'child->bs' + else: + bs = 'blk_bs(blk)' + self.bs = bs def gen_list(self, format: str) -> str: return ', '.join(format.format_map(arg.__dict__) for arg in self.args) @@ -XXX,XX +XXX,XX @@ def gen_block(self, format: str) -> str: return '\n'.join(format.format_map(arg.__dict__) for arg in self.args) -# Match wrappers declared with a co_wrapper_mixed mark -func_decl_re = re.compile(r'^int\s*co_wrapper_mixed\s*' +# Match wrappers declared with a co_wrapper mark +func_decl_re = re.compile(r'^int\s*co_wrapper' + r'(?P<variant>(_[a-z][a-z0-9_]*)?)\s*' r'(?P<wrapper_name>[a-z][a-z0-9_]*)' r'\((?P<args>[^)]*)\);$', re.MULTILINE) @@ -XXX,XX +XXX,XX @@ def func_decl_iter(text: str) -> Iterator: for m in func_decl_re.finditer(text): yield FuncDecl(return_type='int', name=m.group('wrapper_name'), - args=m.group('args')) + args=m.group('args'), + variant=m.group('variant')) def snake_to_camel(func_name: str) -> str: @@ -XXX,XX +XXX,XX @@ def snake_to_camel(func_name: str) -> str: return ''.join(words) +def create_mixed_wrapper(func: FuncDecl) -> str: + """ + Checks if we are already in coroutine + """ + name = func.co_name + struct_name = func.struct_name + return f"""\ +int {func.name}({ func.gen_list('{decl}') }) +{{ + if (qemu_in_coroutine()) {{ + return {name}({ func.gen_list('{name}') }); + }} else {{ + {struct_name} s = {{ + .poll_state.bs = {func.bs}, + .poll_state.in_progress = true, + +{ func.gen_block(' .{name} = {name},') } + }}; + + s.poll_state.co = qemu_coroutine_create({name}_entry, &s); + + return bdrv_poll_co(&s.poll_state); + }} +}}""" + + +def create_co_wrapper(func: FuncDecl) -> str: + """ + Assumes we are not in coroutine, and creates one + """ + name = func.co_name + struct_name = func.struct_name + return f"""\ +int {func.name}({ func.gen_list('{decl}') }) +{{ + {struct_name} s = {{ + .poll_state.bs = {func.bs}, + .poll_state.in_progress = true, + +{ func.gen_block(' .{name} = {name},') } + }}; + assert(!qemu_in_coroutine()); + + s.poll_state.co = qemu_coroutine_create({name}_entry, &s); + + return bdrv_poll_co(&s.poll_state); +}}""" + + def gen_wrapper(func: FuncDecl) -> str: assert not '_co_' in func.name assert func.return_type == 'int' assert func.args[0].type in ['BlockDriverState *', 'BdrvChild *', 'BlockBackend *'] - subsystem, subname = func.name.split('_', 1) - - name = f'{subsystem}_co_{subname}' + name = func.co_name + struct_name = func.struct_name - t = func.args[0].type - if t == 'BlockDriverState *': - bs = 'bs' - elif t == 'BdrvChild *': - bs = 'child->bs' - else: - bs = 'blk_bs(blk)' - struct_name = snake_to_camel(name) + creation_function = create_mixed_wrapper + if func.create_only_co: + creation_function = create_co_wrapper return f"""\ /* @@ -XXX,XX +XXX,XX @@ def gen_wrapper(func: FuncDecl) -> str: aio_wait_kick(); }} -int {func.name}({ func.gen_list('{decl}') }) -{{ - if (qemu_in_coroutine()) {{ - return {name}({ func.gen_list('{name}') }); - }} else {{ - {struct_name} s = {{ - .poll_state.bs = {bs}, - .poll_state.in_progress = true, - -{ func.gen_block(' .{name} = {name},') } - }}; - - s.poll_state.co = qemu_coroutine_create({name}_entry, &s); - - return bdrv_poll_co(&s.poll_state); - }} -}}""" +{creation_function(func)}""" def gen_wrappers(input_code: str) -> str: -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Right now, we take the first parameter of the function to get the BlockDriverState to pass to bdrv_poll_co(), that internally calls functions that figure in which aiocontext the coroutine should run. However, it is useless to pass a bs just to get its own AioContext, so instead pass it directly, and default to the main loop if no BlockDriverState is passed as parameter. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-12-eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/block-gen.h | 6 +++--- scripts/block-coroutine-wrapper.py | 16 ++++++++-------- 2 files changed, 11 insertions(+), 11 deletions(-) diff --git a/block/block-gen.h b/block/block-gen.h index XXXXXXX..XXXXXXX 100644 --- a/block/block-gen.h +++ b/block/block-gen.h @@ -XXX,XX +XXX,XX @@ /* Base structure for argument packing structures */ typedef struct BdrvPollCo { - BlockDriverState *bs; + AioContext *ctx; bool in_progress; int ret; Coroutine *co; /* Keep pointer here for debugging */ @@ -XXX,XX +XXX,XX @@ static inline int bdrv_poll_co(BdrvPollCo *s) { assert(!qemu_in_coroutine()); - bdrv_coroutine_enter(s->bs, s->co); - BDRV_POLL_WHILE(s->bs, s->in_progress); + aio_co_enter(s->ctx, s->co); + AIO_WAIT_WHILE(s->ctx, s->in_progress); return s->ret; } diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index XXXXXXX..XXXXXXX 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -XXX,XX +XXX,XX @@ def __init__(self, return_type: str, name: str, args: str, t = self.args[0].type if t == 'BlockDriverState *': - bs = 'bs' + ctx = 'bdrv_get_aio_context(bs)' elif t == 'BdrvChild *': - bs = 'child->bs' + ctx = 'bdrv_get_aio_context(child->bs)' + elif t == 'BlockBackend *': + ctx = 'blk_get_aio_context(blk)' else: - bs = 'blk_bs(blk)' - self.bs = bs + ctx = 'qemu_get_aio_context()' + self.ctx = ctx def gen_list(self, format: str) -> str: return ', '.join(format.format_map(arg.__dict__) for arg in self.args) @@ -XXX,XX +XXX,XX @@ def create_mixed_wrapper(func: FuncDecl) -> str: return {name}({ func.gen_list('{name}') }); }} else {{ {struct_name} s = {{ - .poll_state.bs = {func.bs}, + .poll_state.ctx = {func.ctx}, .poll_state.in_progress = true, { func.gen_block(' .{name} = {name},') } @@ -XXX,XX +XXX,XX @@ def create_co_wrapper(func: FuncDecl) -> str: int {func.name}({ func.gen_list('{decl}') }) {{ {struct_name} s = {{ - .poll_state.bs = {func.bs}, + .poll_state.ctx = {func.ctx}, .poll_state.in_progress = true, { func.gen_block(' .{name} = {name},') } @@ -XXX,XX +XXX,XX @@ def create_co_wrapper(func: FuncDecl) -> str: def gen_wrapper(func: FuncDecl) -> str: assert not '_co_' in func.name assert func.return_type == 'int' - assert func.args[0].type in ['BlockDriverState *', 'BdrvChild *', - 'BlockBackend *'] name = func.co_name struct_name = func.struct_name -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Extend the regex to cover also return type, pointers included. This implies that the value returned by the function cannot be a simple "int" anymore, but the custom return type. Therefore remove poll_state->ret and instead use a per-function custom "ret" field. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-13-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/block-gen.h | 5 +---- scripts/block-coroutine-wrapper.py | 19 +++++++++++-------- 2 files changed, 12 insertions(+), 12 deletions(-) diff --git a/block/block-gen.h b/block/block-gen.h index XXXXXXX..XXXXXXX 100644 --- a/block/block-gen.h +++ b/block/block-gen.h @@ -XXX,XX +XXX,XX @@ typedef struct BdrvPollCo { AioContext *ctx; bool in_progress; - int ret; Coroutine *co; /* Keep pointer here for debugging */ } BdrvPollCo; -static inline int bdrv_poll_co(BdrvPollCo *s) +static inline void bdrv_poll_co(BdrvPollCo *s) { assert(!qemu_in_coroutine()); aio_co_enter(s->ctx, s->co); AIO_WAIT_WHILE(s->ctx, s->in_progress); - - return s->ret; } #endif /* BLOCK_BLOCK_GEN_H */ diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index XXXXXXX..XXXXXXX 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -XXX,XX +XXX,XX @@ def gen_block(self, format: str) -> str: # Match wrappers declared with a co_wrapper mark -func_decl_re = re.compile(r'^int\s*co_wrapper' +func_decl_re = re.compile(r'^(?P<return_type>[a-zA-Z][a-zA-Z0-9_]* [\*]?)' + r'\s*co_wrapper' r'(?P<variant>(_[a-z][a-z0-9_]*)?)\s*' r'(?P<wrapper_name>[a-z][a-z0-9_]*)' r'\((?P<args>[^)]*)\);$', re.MULTILINE) @@ -XXX,XX +XXX,XX @@ def gen_block(self, format: str) -> str: def func_decl_iter(text: str) -> Iterator: for m in func_decl_re.finditer(text): - yield FuncDecl(return_type='int', + yield FuncDecl(return_type=m.group('return_type'), name=m.group('wrapper_name'), args=m.group('args'), variant=m.group('variant')) @@ -XXX,XX +XXX,XX @@ def create_mixed_wrapper(func: FuncDecl) -> str: name = func.co_name struct_name = func.struct_name return f"""\ -int {func.name}({ func.gen_list('{decl}') }) +{func.return_type} {func.name}({ func.gen_list('{decl}') }) {{ if (qemu_in_coroutine()) {{ return {name}({ func.gen_list('{name}') }); @@ -XXX,XX +XXX,XX @@ def create_mixed_wrapper(func: FuncDecl) -> str: s.poll_state.co = qemu_coroutine_create({name}_entry, &s); - return bdrv_poll_co(&s.poll_state); + bdrv_poll_co(&s.poll_state); + return s.ret; }} }}""" @@ -XXX,XX +XXX,XX @@ def create_co_wrapper(func: FuncDecl) -> str: name = func.co_name struct_name = func.struct_name return f"""\ -int {func.name}({ func.gen_list('{decl}') }) +{func.return_type} {func.name}({ func.gen_list('{decl}') }) {{ {struct_name} s = {{ .poll_state.ctx = {func.ctx}, @@ -XXX,XX +XXX,XX @@ def create_co_wrapper(func: FuncDecl) -> str: s.poll_state.co = qemu_coroutine_create({name}_entry, &s); - return bdrv_poll_co(&s.poll_state); + bdrv_poll_co(&s.poll_state); + return s.ret; }}""" def gen_wrapper(func: FuncDecl) -> str: assert not '_co_' in func.name - assert func.return_type == 'int' name = func.co_name struct_name = func.struct_name @@ -XXX,XX +XXX,XX @@ def gen_wrapper(func: FuncDecl) -> str: typedef struct {struct_name} {{ BdrvPollCo poll_state; + {func.return_type} ret; { func.gen_block(' {decl};') } }} {struct_name}; @@ -XXX,XX +XXX,XX @@ def gen_wrapper(func: FuncDecl) -> str: {{ {struct_name} *s = opaque; - s->poll_state.ret = {name}({ func.gen_list('s->{name}') }); + s->ret = {name}({ func.gen_list('s->{name}') }); s->poll_state.in_progress = false; aio_wait_kick(); -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> This function is never called in coroutine context, therefore instead of manually creating a new coroutine, delegate it to the block-coroutine-wrapper script, defining it as co_wrapper. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-14-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-global-state.h | 8 ++++-- block.c | 41 ++---------------------------- 2 files changed, 8 insertions(+), 41 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -XXX,XX +XXX,XX @@ BlockDriver *bdrv_find_protocol(const char *filename, bool allow_protocol_prefix, Error **errp); BlockDriver *bdrv_find_format(const char *format_name); -int bdrv_create(BlockDriver *drv, const char* filename, - QemuOpts *opts, Error **errp); + +int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, + QemuOpts *opts, Error **errp); +int co_wrapper bdrv_create(BlockDriver *drv, const char *filename, + QemuOpts *opts, Error **errp); + int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts, Error **errp); diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ typedef struct CreateCo { Error *err; } CreateCo; -static int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, - QemuOpts *opts, Error **errp) +int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, + QemuOpts *opts, Error **errp) { int ret; GLOBAL_STATE_CODE(); @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, return ret; } -static void coroutine_fn bdrv_create_co_entry(void *opaque) -{ - CreateCo *cco = opaque; - GLOBAL_STATE_CODE(); - - cco->ret = bdrv_co_create(cco->drv, cco->filename, cco->opts, &cco->err); - aio_wait_kick(); -} - -int bdrv_create(BlockDriver *drv, const char* filename, - QemuOpts *opts, Error **errp) -{ - GLOBAL_STATE_CODE(); - - if (qemu_in_coroutine()) { - /* Fast-path if already in coroutine context */ - return bdrv_co_create(drv, filename, opts, errp); - } else { - Coroutine *co; - CreateCo cco = { - .drv = drv, - .filename = filename, - .opts = opts, - .ret = NOT_DONE, - .err = NULL, - }; - - co = qemu_coroutine_create(bdrv_create_co_entry, &cco); - qemu_coroutine_enter(co); - while (cco.ret == NOT_DONE) { - aio_poll(qemu_get_aio_context(), true); - } - error_propagate(errp, cco.err); - return cco.ret; - } -} - /** * Helper function for bdrv_create_file_fallback(): Resize @blk to at * least the given @minimum_size. -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> bdrv_can_store_new_dirty_bitmap and bdrv_remove_persistent_dirty_bitmap check if they are running in a coroutine, directly calling the coroutine callback if it's the case. Except that no coroutine calls such functions, therefore that check can be removed, and function creation can be offloaded to c_w. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-15-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-common.h | 5 +- include/block/block-io.h | 10 +++- include/block/dirty-bitmap.h | 10 +++- block/dirty-bitmap.c | 88 +----------------------------------- block/meson.build | 1 + 5 files changed, 22 insertions(+), 92 deletions(-) diff --git a/include/block/block-common.h b/include/block/block-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -XXX,XX +XXX,XX @@ #include "qemu/iov.h" #include "qemu/coroutine.h" #include "block/accounting.h" -#include "block/dirty-bitmap.h" -#include "block/blockjob.h" #include "qemu/hbitmap.h" #include "qemu/transactions.h" @@ -XXX,XX +XXX,XX @@ #define co_wrapper #define co_wrapper_mixed +#include "block/dirty-bitmap.h" +#include "block/blockjob.h" + /* block.c */ typedef struct BlockDriver BlockDriver; typedef struct BdrvChild BdrvChild; diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ AioContext *child_of_bds_get_parent_aio_context(BdrvChild *c); void bdrv_io_plug(BlockDriverState *bs); void bdrv_io_unplug(BlockDriverState *bs); -bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, - uint32_t granularity, Error **errp); +bool coroutine_fn bdrv_co_can_store_new_dirty_bitmap(BlockDriverState *bs, + const char *name, + uint32_t granularity, + Error **errp); +bool co_wrapper bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, + const char *name, + uint32_t granularity, + Error **errp); /** * diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -XXX,XX +XXX,XX @@ int bdrv_dirty_bitmap_check(const BdrvDirtyBitmap *bitmap, uint32_t flags, Error **errp); void bdrv_release_dirty_bitmap(BdrvDirtyBitmap *bitmap); void bdrv_release_named_dirty_bitmaps(BlockDriverState *bs); -int bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs, const char *name, - Error **errp); + +int coroutine_fn bdrv_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, + const char *name, + Error **errp); +int co_wrapper bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs, + const char *name, + Error **errp); + void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap); void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap); void bdrv_enable_dirty_bitmap_locked(BdrvDirtyBitmap *bitmap); diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index XXXXXXX..XXXXXXX 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -XXX,XX +XXX,XX @@ void bdrv_release_named_dirty_bitmaps(BlockDriverState *bs) * not fail. * This function doesn't release corresponding BdrvDirtyBitmap. */ -static int coroutine_fn +int coroutine_fn bdrv_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, const char *name, Error **errp) { @@ -XXX,XX +XXX,XX @@ bdrv_co_remove_persistent_dirty_bitmap(BlockDriverState *bs, const char *name, return 0; } -typedef struct BdrvRemovePersistentDirtyBitmapCo { - BlockDriverState *bs; - const char *name; - Error **errp; - int ret; -} BdrvRemovePersistentDirtyBitmapCo; - -static void coroutine_fn -bdrv_co_remove_persistent_dirty_bitmap_entry(void *opaque) -{ - BdrvRemovePersistentDirtyBitmapCo *s = opaque; - - s->ret = bdrv_co_remove_persistent_dirty_bitmap(s->bs, s->name, s->errp); - aio_wait_kick(); -} - -int bdrv_remove_persistent_dirty_bitmap(BlockDriverState *bs, const char *name, - Error **errp) -{ - if (qemu_in_coroutine()) { - return bdrv_co_remove_persistent_dirty_bitmap(bs, name, errp); - } else { - Coroutine *co; - BdrvRemovePersistentDirtyBitmapCo s = { - .bs = bs, - .name = name, - .errp = errp, - .ret = -EINPROGRESS, - }; - - co = qemu_coroutine_create(bdrv_co_remove_persistent_dirty_bitmap_entry, - &s); - bdrv_coroutine_enter(bs, co); - BDRV_POLL_WHILE(bs, s.ret == -EINPROGRESS); - - return s.ret; - } -} - bool bdrv_supports_persistent_dirty_bitmap(BlockDriverState *bs) { @@ -XXX,XX +XXX,XX @@ bdrv_supports_persistent_dirty_bitmap(BlockDriverState *bs) return false; } -static bool coroutine_fn +bool coroutine_fn bdrv_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, uint32_t granularity, Error **errp) { @@ -XXX,XX +XXX,XX @@ bdrv_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, return drv->bdrv_co_can_store_new_dirty_bitmap(bs, name, granularity, errp); } -typedef struct BdrvCanStoreNewDirtyBitmapCo { - BlockDriverState *bs; - const char *name; - uint32_t granularity; - Error **errp; - bool ret; - - bool in_progress; -} BdrvCanStoreNewDirtyBitmapCo; - -static void coroutine_fn bdrv_co_can_store_new_dirty_bitmap_entry(void *opaque) -{ - BdrvCanStoreNewDirtyBitmapCo *s = opaque; - - s->ret = bdrv_co_can_store_new_dirty_bitmap(s->bs, s->name, s->granularity, - s->errp); - s->in_progress = false; - aio_wait_kick(); -} - -bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, - uint32_t granularity, Error **errp) -{ - IO_CODE(); - if (qemu_in_coroutine()) { - return bdrv_co_can_store_new_dirty_bitmap(bs, name, granularity, errp); - } else { - Coroutine *co; - BdrvCanStoreNewDirtyBitmapCo s = { - .bs = bs, - .name = name, - .granularity = granularity, - .errp = errp, - .in_progress = true, - }; - - co = qemu_coroutine_create(bdrv_co_can_store_new_dirty_bitmap_entry, - &s); - bdrv_coroutine_enter(bs, co); - BDRV_POLL_WHILE(bs, s.in_progress); - - return s.ret; - } -} - void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap) { bdrv_dirty_bitmaps_lock(bitmap->bs); diff --git a/block/meson.build b/block/meson.build index XXXXXXX..XXXXXXX 100644 --- a/block/meson.build +++ b/block/meson.build @@ -XXX,XX +XXX,XX @@ block_gen_c = custom_target('block-gen.c', output: 'block-gen.c', input: files( '../include/block/block-io.h', + '../include/block/dirty-bitmap.h', '../include/block/block-global-state.h', '../include/sysemu/block-backend-io.h', 'coroutines.h' -- 2.38.1 Provide a separate function that just quiesces the users of a node to prevent new requests from coming in, but without waiting for the already in-flight I/O to complete. This function can be used in contexts where polling is not allowed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-2-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-global-state.h | 1 + block/io.c | 19 +++++++++++++------ 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/include/block/block-global-state.h b/include/block/block-global-state.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-global-state.h +++ b/include/block/block-global-state.h @@ -XXX,XX +XXX,XX @@ int bdrv_inactivate_all(void); int bdrv_flush_all(void); void bdrv_close_all(void); void bdrv_drain_all_begin(void); +void bdrv_drain_all_begin_nopoll(void); void bdrv_drain_all_end(void); void bdrv_drain_all(void); diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ static bool bdrv_drain_all_poll(void) * NOTE: no new block jobs or BlockDriverStates can be created between * the bdrv_drain_all_begin() and bdrv_drain_all_end() calls. */ -void bdrv_drain_all_begin(void) +void bdrv_drain_all_begin_nopoll(void) { BlockDriverState *bs = NULL; GLOBAL_STATE_CODE(); - if (qemu_in_coroutine()) { - bdrv_co_yield_to_drain(NULL, true, NULL, true); - return; - } - /* * bdrv queue is managed by record/replay, * waiting for finishing the I/O requests may @@ -XXX,XX +XXX,XX @@ void bdrv_drain_all_begin(void) bdrv_do_drained_begin(bs, NULL, false); aio_context_release(aio_context); } +} + +void bdrv_drain_all_begin(void) +{ + BlockDriverState *bs = NULL; + + if (qemu_in_coroutine()) { + bdrv_co_yield_to_drain(NULL, true, NULL, true); + return; + } + + bdrv_drain_all_begin_nopoll(); /* Now poll the in-flight requests */ AIO_WAIT_WHILE(NULL, bdrv_drain_all_poll()); -- 2.38.1 From: Paolo Bonzini <pbonzini@redhat.com> Block layer graph operations are always run under BQL in the main loop. This is proved by the assertion qemu_in_main_thread() and its wrapper macro GLOBAL_STATE_CODE. However, there are also concurrent coroutines running in other iothreads that always try to traverse the graph. Currently this is protected (among various other things) by the AioContext lock, but once this is removed, we need to make sure that reads do not happen while modifying the graph. We distinguish between writer (main loop, under BQL) that modifies the graph, and readers (all other coroutines running in various AioContext), that go through the graph edges, reading ->parents and->children. The writer (main loop) has "exclusive" access, so it first waits for any current read to finish, and then prevents incoming ones from entering while it has the exclusive access. The readers (coroutines in multiple AioContext) are free to access the graph as long the writer is not modifying the graph. In case it is, they go in a CoQueue and sleep until the writer is done. If a coroutine changes AioContext, the counter in the original and new AioContext are left intact, since the writer does not care where the reader is, but only if there is one. As a result, some AioContexts might have a negative reader count, to balance the positive count of the AioContext that took the lock. This also means that when an AioContext is deleted it may have a nonzero reader count. In that case we transfer the count to a global shared counter so that the writer is always aware of all readers. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-3-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/aio.h | 9 ++ include/block/block_int.h | 1 + include/block/graph-lock.h | 139 ++++++++++++++++++++ block/graph-lock.c | 261 +++++++++++++++++++++++++++++++++++++ block/meson.build | 1 + 5 files changed, 411 insertions(+) create mode 100644 include/block/graph-lock.h create mode 100644 block/graph-lock.c diff --git a/include/block/aio.h b/include/block/aio.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/aio.h +++ b/include/block/aio.h @@ -XXX,XX +XXX,XX @@ #include "qemu/event_notifier.h" #include "qemu/thread.h" #include "qemu/timer.h" +#include "block/graph-lock.h" typedef struct BlockAIOCB BlockAIOCB; typedef void BlockCompletionFunc(void *opaque, int ret); @@ -XXX,XX +XXX,XX @@ struct AioContext { /* Used by AioContext users to protect from multi-threaded access. */ QemuRecMutex lock; + /* + * Keep track of readers and writers of the block layer graph. + * This is essential to avoid performing additions and removal + * of nodes and edges from block graph while some + * other thread is traversing it. + */ + BdrvGraphRWlock *bdrv_graph; + /* The list of registered AIO handlers. Protected by ctx->list_lock. */ AioHandlerList aio_handlers; diff --git a/include/block/block_int.h b/include/block/block_int.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -XXX,XX +XXX,XX @@ #include "block_int-global-state.h" #include "block_int-io.h" +#include "block/graph-lock.h" /* DO NOT ADD ANYTHING IN HERE. USE ONE OF THE HEADERS INCLUDED ABOVE */ diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/include/block/graph-lock.h @@ -XXX,XX +XXX,XX @@ +/* + * Graph lock: rwlock to protect block layer graph manipulations (add/remove + * edges and nodes) + * + * Copyright (c) 2022 Red Hat + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + */ +#ifndef GRAPH_LOCK_H +#define GRAPH_LOCK_H + +#include "qemu/osdep.h" + +#include "qemu/coroutine.h" + +/** + * Graph Lock API + * This API provides a rwlock used to protect block layer + * graph modifications like edge (BdrvChild) and node (BlockDriverState) + * addition and removal. + * Currently we have 1 writer only, the Main loop, and many + * readers, mostly coroutines running in other AioContext thus other threads. + * + * We distinguish between writer (main loop, under BQL) that modifies the + * graph, and readers (all other coroutines running in various AioContext), + * that go through the graph edges, reading + * BlockDriverState ->parents and->children. + * + * The writer (main loop) has an "exclusive" access, so it first waits for + * current read to finish, and then prevents incoming ones from + * entering while it has the exclusive access. + * + * The readers (coroutines in multiple AioContext) are free to + * access the graph as long the writer is not modifying the graph. + * In case it is, they go in a CoQueue and sleep until the writer + * is done. + * + * If a coroutine changes AioContext, the counter in the original and new + * AioContext are left intact, since the writer does not care where is the + * reader, but only if there is one. + * As a result, some AioContexts might have a negative reader count, to + * balance the positive count of the AioContext that took the lock. + * This also means that when an AioContext is deleted it may have a nonzero + * reader count. In that case we transfer the count to a global shared counter + * so that the writer is always aware of all readers. + */ +typedef struct BdrvGraphRWlock BdrvGraphRWlock; + +/* + * register_aiocontext: + * Add AioContext @ctx to the list of AioContext. + * This list is used to obtain the total number of readers + * currently running the graph. + */ +void register_aiocontext(AioContext *ctx); + +/* + * unregister_aiocontext: + * Removes AioContext @ctx to the list of AioContext. + */ +void unregister_aiocontext(AioContext *ctx); + +/* + * bdrv_graph_wrlock: + * Start an exclusive write operation to modify the graph. This means we are + * adding or removing an edge or a node in the block layer graph. Nobody else + * is allowed to access the graph. + * + * Must only be called from outside bdrv_graph_co_rdlock. + * + * The wrlock can only be taken from the main loop, with BQL held, as only the + * main loop is allowed to modify the graph. + * + * This function polls. Callers must not hold the lock of any AioContext other + * than the current one. + */ +void bdrv_graph_wrlock(void); + +/* + * bdrv_graph_wrunlock: + * Write finished, reset global has_writer to 0 and restart + * all readers that are waiting. + */ +void bdrv_graph_wrunlock(void); + +/* + * bdrv_graph_co_rdlock: + * Read the bs graph. This usually means traversing all nodes in + * the graph, therefore it can't happen while another thread is + * modifying it. + * Increases the reader counter of the current aiocontext, + * and if has_writer is set, it means that the writer is modifying + * the graph, therefore wait in a coroutine queue. + * The writer will then wake this coroutine once it is done. + * + * This lock should be taken from Iothreads (IO_CODE() class of functions) + * because it signals the writer that there are some + * readers currently running, or waits until the current + * write is finished before continuing. + * Calling this function from the Main Loop with BQL held + * is not necessary, since the Main Loop itself is the only + * writer, thus won't be able to read and write at the same time. + * The only exception to that is when we can't take the lock in the + * function/coroutine itself, and need to delegate the caller (usually main + * loop) to take it and wait that the coroutine ends, so that + * we always signal that a reader is running. + */ +void coroutine_fn bdrv_graph_co_rdlock(void); + +/* + * bdrv_graph_rdunlock: + * Read terminated, decrease the count of readers in the current aiocontext. + * If the writer is waiting for reads to finish (has_writer == 1), signal + * the writer that we are done via aio_wait_kick() to let it continue. + */ +void coroutine_fn bdrv_graph_co_rdunlock(void); + +/* + * bdrv_graph_rd{un}lock_main_loop: + * Just a placeholder to mark where the graph rdlock should be taken + * in the main loop. It is just asserting that we are not + * in a coroutine and in GLOBAL_STATE_CODE. + */ +void bdrv_graph_rdlock_main_loop(void); +void bdrv_graph_rdunlock_main_loop(void); + +#endif /* GRAPH_LOCK_H */ + diff --git a/block/graph-lock.c b/block/graph-lock.c new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/block/graph-lock.c @@ -XXX,XX +XXX,XX @@ +/* + * Graph lock: rwlock to protect block layer graph manipulations (add/remove + * edges and nodes) + * + * Copyright (c) 2022 Red Hat + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "qemu/main-loop.h" +#include "block/graph-lock.h" +#include "block/block.h" +#include "block/block_int.h" + +/* Protects the list of aiocontext and orphaned_reader_count */ +static QemuMutex aio_context_list_lock; + +/* Written and read with atomic operations. */ +static int has_writer; + +/* + * A reader coroutine could move from an AioContext to another. + * If this happens, there is no problem from the point of view of + * counters. The problem is that the total count becomes + * unbalanced if one of the two AioContexts gets deleted. + * The count of readers must remain correct, so the AioContext's + * balance is transferred to this glboal variable. + * Protected by aio_context_list_lock. + */ +static uint32_t orphaned_reader_count; + +/* Queue of readers waiting for the writer to finish */ +static CoQueue reader_queue; + +struct BdrvGraphRWlock { + /* How many readers are currently reading the graph. */ + uint32_t reader_count; + + /* + * List of BdrvGraphRWlock kept in graph-lock.c + * Protected by aio_context_list_lock + */ + QTAILQ_ENTRY(BdrvGraphRWlock) next_aio; +}; + +/* + * List of BdrvGraphRWlock. This list ensures that each BdrvGraphRWlock + * can safely modify only its own counter, avoid reading/writing + * others and thus improving performances by avoiding cacheline bounces. + */ +static QTAILQ_HEAD(, BdrvGraphRWlock) aio_context_list = + QTAILQ_HEAD_INITIALIZER(aio_context_list); + +static void __attribute__((__constructor__)) bdrv_init_graph_lock(void) +{ + qemu_mutex_init(&aio_context_list_lock); + qemu_co_queue_init(&reader_queue); +} + +void register_aiocontext(AioContext *ctx) +{ + ctx->bdrv_graph = g_new0(BdrvGraphRWlock, 1); + QEMU_LOCK_GUARD(&aio_context_list_lock); + assert(ctx->bdrv_graph->reader_count == 0); + QTAILQ_INSERT_TAIL(&aio_context_list, ctx->bdrv_graph, next_aio); +} + +void unregister_aiocontext(AioContext *ctx) +{ + QEMU_LOCK_GUARD(&aio_context_list_lock); + orphaned_reader_count += ctx->bdrv_graph->reader_count; + QTAILQ_REMOVE(&aio_context_list, ctx->bdrv_graph, next_aio); + g_free(ctx->bdrv_graph); +} + +static uint32_t reader_count(void) +{ + BdrvGraphRWlock *brdv_graph; + uint32_t rd; + + QEMU_LOCK_GUARD(&aio_context_list_lock); + + /* rd can temporarly be negative, but the total will *always* be >= 0 */ + rd = orphaned_reader_count; + QTAILQ_FOREACH(brdv_graph, &aio_context_list, next_aio) { + rd += qatomic_read(&brdv_graph->reader_count); + } + + /* shouldn't overflow unless there are 2^31 readers */ + assert((int32_t)rd >= 0); + return rd; +} + +void bdrv_graph_wrlock(void) +{ + GLOBAL_STATE_CODE(); + assert(!qatomic_read(&has_writer)); + + /* Make sure that constantly arriving new I/O doesn't cause starvation */ + bdrv_drain_all_begin_nopoll(); + + /* + * reader_count == 0: this means writer will read has_reader as 1 + * reader_count >= 1: we don't know if writer read has_writer == 0 or 1, + * but we need to wait. + * Wait by allowing other coroutine (and possible readers) to continue. + */ + do { + /* + * has_writer must be 0 while polling, otherwise we get a deadlock if + * any callback involved during AIO_WAIT_WHILE() tries to acquire the + * reader lock. + */ + qatomic_set(&has_writer, 0); + AIO_WAIT_WHILE(qemu_get_aio_context(), reader_count() >= 1); + qatomic_set(&has_writer, 1); + + /* + * We want to only check reader_count() after has_writer = 1 is visible + * to other threads. That way no more readers can sneak in after we've + * determined reader_count() == 0. + */ + smp_mb(); + } while (reader_count() >= 1); + + bdrv_drain_all_end(); +} + +void bdrv_graph_wrunlock(void) +{ + GLOBAL_STATE_CODE(); + QEMU_LOCK_GUARD(&aio_context_list_lock); + assert(qatomic_read(&has_writer)); + + /* + * No need for memory barriers, this works in pair with + * the slow path of rdlock() and both take the lock. + */ + qatomic_store_release(&has_writer, 0); + + /* Wake up all coroutine that are waiting to read the graph */ + qemu_co_enter_all(&reader_queue, &aio_context_list_lock); +} + +void coroutine_fn bdrv_graph_co_rdlock(void) +{ + BdrvGraphRWlock *bdrv_graph; + bdrv_graph = qemu_get_current_aio_context()->bdrv_graph; + + /* Do not lock if in main thread */ + if (qemu_in_main_thread()) { + return; + } + + for (;;) { + qatomic_set(&bdrv_graph->reader_count, + bdrv_graph->reader_count + 1); + /* make sure writer sees reader_count before we check has_writer */ + smp_mb(); + + /* + * has_writer == 0: this means writer will read reader_count as >= 1 + * has_writer == 1: we don't know if writer read reader_count == 0 + * or > 0, but we need to wait anyways because + * it will write. + */ + if (!qatomic_read(&has_writer)) { + break; + } + + /* + * Synchronize access with reader_count() in bdrv_graph_wrlock(). + * Case 1: + * If this critical section gets executed first, reader_count will + * decrease and the reader will go to sleep. + * Then the writer will read reader_count that does not take into + * account this reader, and if there's no other reader it will + * enter the write section. + * Case 2: + * If reader_count() critical section gets executed first, + * then writer will read reader_count >= 1. + * It will wait in AIO_WAIT_WHILE(), but once it releases the lock + * we will enter this critical section and call aio_wait_kick(). + */ + WITH_QEMU_LOCK_GUARD(&aio_context_list_lock) { + /* + * Additional check when we use the above lock to synchronize + * with bdrv_graph_wrunlock(). + * Case 1: + * If this gets executed first, has_writer is still 1, so we reduce + * reader_count and go to sleep. + * Then the writer will set has_writer to 0 and wake up all readers, + * us included. + * Case 2: + * If bdrv_graph_wrunlock() critical section gets executed first, + * then it will set has_writer to 0 and wake up all other readers. + * Then we execute this critical section, and therefore must check + * again for has_writer, otherwise we sleep without any writer + * actually running. + */ + if (!qatomic_read(&has_writer)) { + return; + } + + /* slow path where reader sleeps */ + bdrv_graph->reader_count--; + aio_wait_kick(); + qemu_co_queue_wait(&reader_queue, &aio_context_list_lock); + } + } +} + +void coroutine_fn bdrv_graph_co_rdunlock(void) +{ + BdrvGraphRWlock *bdrv_graph; + bdrv_graph = qemu_get_current_aio_context()->bdrv_graph; + + /* Do not lock if in main thread */ + if (qemu_in_main_thread()) { + return; + } + + qatomic_store_release(&bdrv_graph->reader_count, + bdrv_graph->reader_count - 1); + /* make sure writer sees reader_count before we check has_writer */ + smp_mb(); + + /* + * has_writer == 0: this means reader will read reader_count decreased + * has_writer == 1: we don't know if writer read reader_count old or + * new. Therefore, kick again so on next iteration + * writer will for sure read the updated value. + */ + if (qatomic_read(&has_writer)) { + aio_wait_kick(); + } +} + +void bdrv_graph_rdlock_main_loop(void) +{ + GLOBAL_STATE_CODE(); + assert(!qemu_in_coroutine()); +} + +void bdrv_graph_rdunlock_main_loop(void) +{ + GLOBAL_STATE_CODE(); + assert(!qemu_in_coroutine()); +} diff --git a/block/meson.build b/block/meson.build index XXXXXXX..XXXXXXX 100644 --- a/block/meson.build +++ b/block/meson.build @@ -XXX,XX +XXX,XX @@ block_ss.add(files( 'blkverify.c', 'block-backend.c', 'block-copy.c', + 'graph-lock.c', 'commit.c', 'copy-on-read.c', 'preallocate.c', -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Similar to the implementation in lockable.h, implement macros to automatically take and release the rdlock. Create the empty GraphLockable and GraphLockableMainloop structs only to use it as a type for G_DEFINE_AUTOPTR_CLEANUP_FUNC. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-4-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/graph-lock.h | 66 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -XXX,XX +XXX,XX @@ void coroutine_fn bdrv_graph_co_rdunlock(void); void bdrv_graph_rdlock_main_loop(void); void bdrv_graph_rdunlock_main_loop(void); +typedef struct GraphLockable { } GraphLockable; + +/* + * In C, compound literals have the lifetime of an automatic variable. + * In C++ it would be different, but then C++ wouldn't need QemuLockable + * either... + */ +#define GML_OBJ_() (&(GraphLockable) { }) + +static inline GraphLockable *graph_lockable_auto_lock(GraphLockable *x) +{ + bdrv_graph_co_rdlock(); + return x; +} + +static inline void graph_lockable_auto_unlock(GraphLockable *x) +{ + bdrv_graph_co_rdunlock(); +} + +G_DEFINE_AUTOPTR_CLEANUP_FUNC(GraphLockable, graph_lockable_auto_unlock) + +#define WITH_GRAPH_RDLOCK_GUARD_(var) \ + for (g_autoptr(GraphLockable) var = graph_lockable_auto_lock(GML_OBJ_()); \ + var; \ + graph_lockable_auto_unlock(var), var = NULL) + +#define WITH_GRAPH_RDLOCK_GUARD() \ + WITH_GRAPH_RDLOCK_GUARD_(glue(graph_lockable_auto, __COUNTER__)) + +#define GRAPH_RDLOCK_GUARD(x) \ + g_autoptr(GraphLockable) \ + glue(graph_lockable_auto, __COUNTER__) G_GNUC_UNUSED = \ + graph_lockable_auto_lock(GML_OBJ_()) + + +typedef struct GraphLockableMainloop { } GraphLockableMainloop; + +/* + * In C, compound literals have the lifetime of an automatic variable. + * In C++ it would be different, but then C++ wouldn't need QemuLockable + * either... + */ +#define GMLML_OBJ_() (&(GraphLockableMainloop) { }) + +static inline GraphLockableMainloop * +graph_lockable_auto_lock_mainloop(GraphLockableMainloop *x) +{ + bdrv_graph_rdlock_main_loop(); + return x; +} + +static inline void +graph_lockable_auto_unlock_mainloop(GraphLockableMainloop *x) +{ + bdrv_graph_rdunlock_main_loop(); +} + +G_DEFINE_AUTOPTR_CLEANUP_FUNC(GraphLockableMainloop, + graph_lockable_auto_unlock_mainloop) + +#define GRAPH_RDLOCK_GUARD_MAINLOOP(x) \ + g_autoptr(GraphLockableMainloop) \ + glue(graph_lockable_auto, __COUNTER__) G_GNUC_UNUSED = \ + graph_lockable_auto_lock_mainloop(GMLML_OBJ_()) + #endif /* GRAPH_LOCK_H */ -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Add/remove the AioContext in aio_context_list in graph-lock.c when it is created/destroyed. This allows using the graph locking operations from this AioContext. In order to allow linking util/async.c with binaries that don't include the block layer, introduce stubs for (un)register_aiocontext(). Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-5-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- stubs/graph-lock.c | 10 ++++++++++ util/async.c | 4 ++++ stubs/meson.build | 1 + 3 files changed, 15 insertions(+) create mode 100644 stubs/graph-lock.c diff --git a/stubs/graph-lock.c b/stubs/graph-lock.c new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/stubs/graph-lock.c @@ -XXX,XX +XXX,XX @@ +#include "qemu/osdep.h" +#include "block/graph-lock.h" + +void register_aiocontext(AioContext *ctx) +{ +} + +void unregister_aiocontext(AioContext *ctx) +{ +} diff --git a/util/async.c b/util/async.c index XXXXXXX..XXXXXXX 100644 --- a/util/async.c +++ b/util/async.c @@ -XXX,XX +XXX,XX @@ #include "qapi/error.h" #include "block/aio.h" #include "block/thread-pool.h" +#include "block/graph-lock.h" #include "qemu/main-loop.h" #include "qemu/atomic.h" #include "qemu/rcu_queue.h" @@ -XXX,XX +XXX,XX @@ aio_ctx_finalize(GSource *source) qemu_rec_mutex_destroy(&ctx->lock); qemu_lockcnt_destroy(&ctx->list_lock); timerlistgroup_deinit(&ctx->tlg); + unregister_aiocontext(ctx); aio_context_destroy(ctx); } @@ -XXX,XX +XXX,XX @@ AioContext *aio_context_new(Error **errp) ctx->thread_pool_min = 0; ctx->thread_pool_max = THREAD_POOL_MAX_THREADS_DEFAULT; + register_aiocontext(ctx); + return ctx; fail: g_source_destroy(&ctx->source); diff --git a/stubs/meson.build b/stubs/meson.build index XXXXXXX..XXXXXXX 100644 --- a/stubs/meson.build +++ b/stubs/meson.build @@ -XXX,XX +XXX,XX @@ stub_ss.add(files('error-printf.c')) stub_ss.add(files('fdset.c')) stub_ss.add(files('gdbstub.c')) stub_ss.add(files('get-vm-name.c')) +stub_ss.add(files('graph-lock.c')) if linux_io_uring.found() stub_ss.add(files('io_uring.c')) endif -- 2.38.1 This defines macros that allow clang to perform Thread Safety Analysis based on function and variable annotations that specify the locking rules. On non-clang compilers, the annotations are ignored. Imported tsa.h from the original repository with the pthread_mutex_t wrapper removed: https://github.com/jhi/clang-thread-safety-analysis-for-c.git Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-6-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/qemu/clang-tsa.h | 101 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 include/qemu/clang-tsa.h diff --git a/include/qemu/clang-tsa.h b/include/qemu/clang-tsa.h new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/include/qemu/clang-tsa.h @@ -XXX,XX +XXX,XX @@ +#ifndef CLANG_TSA_H +#define CLANG_TSA_H + +/* + * Copyright 2018 Jarkko Hietaniemi <jhi@iki.fi> + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without + * limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY + * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +/* http://clang.llvm.org/docs/ThreadSafetyAnalysis.html + * + * TSA is available since clang 3.6-ish. + */ +#ifdef __clang__ +# define TSA(x) __attribute__((x)) +#else +# define TSA(x) /* No TSA, make TSA attributes no-ops. */ +#endif + +/* TSA_CAPABILITY() is used to annotate typedefs: + * + * typedef pthread_mutex_t TSA_CAPABILITY("mutex") tsa_mutex; + */ +#define TSA_CAPABILITY(x) TSA(capability(x)) + +/* TSA_GUARDED_BY() is used to annotate global variables, + * the data is guarded: + * + * Foo foo TSA_GUARDED_BY(mutex); + */ +#define TSA_GUARDED_BY(x) TSA(guarded_by(x)) + +/* TSA_PT_GUARDED_BY() is used to annotate global pointers, the data + * behind the pointer is guarded. + * + * Foo* ptr TSA_PT_GUARDED_BY(mutex); + */ +#define TSA_PT_GUARDED_BY(x) TSA(pt_guarded_by(x)) + +/* The TSA_REQUIRES() is used to annotate functions: the caller of the + * function MUST hold the resource, the function will NOT release it. + * + * More than one mutex may be specified, comma-separated. + * + * void Foo(void) TSA_REQUIRES(mutex); + */ +#define TSA_REQUIRES(...) TSA(requires_capability(__VA_ARGS__)) + +/* TSA_EXCLUDES() is used to annotate functions: the caller of the + * function MUST NOT hold resource, the function first acquires the + * resource, and then releases it. + * + * More than one mutex may be specified, comma-separated. + * + * void Foo(void) TSA_EXCLUDES(mutex); + */ +#define TSA_EXCLUDES(...) TSA(locks_excluded(__VA_ARGS__)) + +/* TSA_ACQUIRE() is used to annotate functions: the caller of the + * function MUST NOT hold the resource, the function will acquire the + * resource, but NOT release it. + * + * More than one mutex may be specified, comma-separated. + * + * void Foo(void) TSA_ACQUIRE(mutex); + */ +#define TSA_ACQUIRE(...) TSA(acquire_capability(__VA_ARGS__)) + +/* TSA_RELEASE() is used to annotate functions: the caller of the + * function MUST hold the resource, but the function will then release it. + * + * More than one mutex may be specified, comma-separated. + * + * void Foo(void) TSA_RELEASE(mutex); + */ +#define TSA_RELEASE(...) TSA(release_capability(__VA_ARGS__)) + +/* TSA_NO_TSA is used to annotate functions. Use only when you need to. + * + * void Foo(void) TSA_NO_TSA; + */ +#define TSA_NO_TSA TSA(no_thread_safety_analysis) + +#endif /* #ifndef CLANG_TSA_H */ -- 2.38.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-7-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/qemu/clang-tsa.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/qemu/clang-tsa.h b/include/qemu/clang-tsa.h index XXXXXXX..XXXXXXX 100644 --- a/include/qemu/clang-tsa.h +++ b/include/qemu/clang-tsa.h @@ -XXX,XX +XXX,XX @@ */ #define TSA_NO_TSA TSA(no_thread_safety_analysis) +/* + * TSA_ASSERT() is used to annotate functions: This function will assert that + * the lock is held. When it returns, the caller of the function is assumed to + * already hold the resource. + * + * More than one mutex may be specified, comma-separated. + */ +#define TSA_ASSERT(...) TSA(assert_capability(__VA_ARGS__)) + #endif /* #ifndef CLANG_TSA_H */ -- 2.38.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-8-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/qemu/clang-tsa.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/qemu/clang-tsa.h b/include/qemu/clang-tsa.h index XXXXXXX..XXXXXXX 100644 --- a/include/qemu/clang-tsa.h +++ b/include/qemu/clang-tsa.h @@ -XXX,XX +XXX,XX @@ * void Foo(void) TSA_REQUIRES(mutex); */ #define TSA_REQUIRES(...) TSA(requires_capability(__VA_ARGS__)) +#define TSA_REQUIRES_SHARED(...) TSA(requires_shared_capability(__VA_ARGS__)) /* TSA_EXCLUDES() is used to annotate functions: the caller of the * function MUST NOT hold resource, the function first acquires the @@ -XXX,XX +XXX,XX @@ * void Foo(void) TSA_ACQUIRE(mutex); */ #define TSA_ACQUIRE(...) TSA(acquire_capability(__VA_ARGS__)) +#define TSA_ACQUIRE_SHARED(...) TSA(acquire_shared_capability(__VA_ARGS__)) /* TSA_RELEASE() is used to annotate functions: the caller of the * function MUST hold the resource, but the function will then release it. @@ -XXX,XX +XXX,XX @@ * void Foo(void) TSA_RELEASE(mutex); */ #define TSA_RELEASE(...) TSA(release_capability(__VA_ARGS__)) +#define TSA_RELEASE_SHARED(...) TSA(release_shared_capability(__VA_ARGS__)) /* TSA_NO_TSA is used to annotate functions. Use only when you need to. * @@ -XXX,XX +XXX,XX @@ * More than one mutex may be specified, comma-separated. */ #define TSA_ASSERT(...) TSA(assert_capability(__VA_ARGS__)) +#define TSA_ASSERT_SHARED(...) TSA(assert_shared_capability(__VA_ARGS__)) #endif /* #ifndef CLANG_TSA_H */ -- 2.38.1 This enables clang's thread safety analysis (TSA), which we'll use to statically check the block graph locking. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-9-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- configure | 1 + 1 file changed, 1 insertion(+) diff --git a/configure b/configure index XXXXXXX..XXXXXXX 100755 --- a/configure +++ b/configure @@ -XXX,XX +XXX,XX @@ add_to warn_flags -Wnested-externs add_to warn_flags -Wendif-labels add_to warn_flags -Wexpansion-to-defined add_to warn_flags -Wimplicit-fallthrough=2 +add_to warn_flags -Wthread-safety nowarn_flags= add_to nowarn_flags -Wno-initializer-overrides -- 2.38.1 The test case assumes that a drain only happens in one specific place where it drains explicitly. This assumption happened to hold true until now, but block layer functions may drain interally (any graph modifications are going to do that through bdrv_graph_wrlock()), so this is incorrect. Make sure that the test code in .drained_begin only runs where we actually want it to run. When scheduling a BH from .drained_begin, we also need to increase the in_flight counter to make sure that the operation is actually completed in time before the node that it works on goes away. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-10-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/unit/test-bdrv-drain.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c index XXXXXXX..XXXXXXX 100644 --- a/tests/unit/test-bdrv-drain.c +++ b/tests/unit/test-bdrv-drain.c @@ -XXX,XX +XXX,XX @@ struct detach_by_parent_data { BlockDriverState *c; BdrvChild *child_c; bool by_parent_cb; + bool detach_on_drain; }; static struct detach_by_parent_data detach_by_parent_data; @@ -XXX,XX +XXX,XX @@ static void detach_indirect_bh(void *opaque) { struct detach_by_parent_data *data = opaque; + bdrv_dec_in_flight(data->child_b->bs); bdrv_unref_child(data->parent_b, data->child_b); bdrv_ref(data->c); @@ -XXX,XX +XXX,XX @@ static void detach_by_parent_aio_cb(void *opaque, int ret) g_assert_cmpint(ret, ==, 0); if (data->by_parent_cb) { + bdrv_inc_in_flight(data->child_b->bs); detach_indirect_bh(data); } } static void detach_by_driver_cb_drained_begin(BdrvChild *child) { + struct detach_by_parent_data *data = &detach_by_parent_data; + + if (!data->detach_on_drain) { + return; + } + data->detach_on_drain = false; + + bdrv_inc_in_flight(data->child_b->bs); aio_bh_schedule_oneshot(qemu_get_current_aio_context(), detach_indirect_bh, &detach_by_parent_data); child_of_bds.drained_begin(child); @@ -XXX,XX +XXX,XX @@ static void test_detach_indirect(bool by_parent_cb) detach_by_driver_cb_class = child_of_bds; detach_by_driver_cb_class.drained_begin = detach_by_driver_cb_drained_begin; + detach_by_driver_cb_class.drained_end = NULL; + detach_by_driver_cb_class.drained_poll = NULL; } + detach_by_parent_data = (struct detach_by_parent_data) { + .detach_on_drain = false, + }; + /* Create all involved nodes */ parent_a = bdrv_new_open_driver(&bdrv_test, "parent-a", BDRV_O_RDWR, &error_abort); @@ -XXX,XX +XXX,XX @@ static void test_detach_indirect(bool by_parent_cb) .child_b = child_b, .c = c, .by_parent_cb = by_parent_cb, + .detach_on_drain = true, }; acb = blk_aio_preadv(blk, 0, &qiov, 0, detach_by_parent_aio_cb, NULL); g_assert(acb != NULL); -- 2.38.1 bdrv_img_create() polls internally (when calling bdrv_create(), which is a co_wrapper), so it can't be called while holding the lock of any AioContext except the current one without causing deadlocks. Drop the lock around the call in external_snapshot_prepare(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-11-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 4 ++++ blockdev.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ bool bdrv_op_blocker_is_empty(BlockDriverState *bs) return true; } +/* + * Must not be called while holding the lock of an AioContext other than the + * current one. + */ void bdrv_img_create(const char *filename, const char *fmt, const char *base_filename, const char *base_fmt, char *options, uint64_t img_size, int flags, bool quiet, diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ static void external_snapshot_prepare(BlkActionState *common, goto out; } bdrv_refresh_filename(state->old_bs); + + aio_context_release(aio_context); bdrv_img_create(new_image_file, format, state->old_bs->filename, state->old_bs->drv->format_name, NULL, size, flags, false, &local_err); + aio_context_acquire(aio_context); + if (local_err) { error_propagate(errp, local_err); goto out; -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Protect the main function where graph is modified. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-12-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm) * * If @new_bs is non-NULL, the parent of @child must already be drained through * @child. - * - * This function does not poll. */ static void bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs) @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child_noperm(BdrvChild *child, assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)); } + /* TODO Pull this up into the callers to avoid polling here */ + bdrv_graph_wrlock(); if (old_bs) { if (child->klass->detach) { child->klass->detach(child); } - assert_bdrv_graph_writable(old_bs); QLIST_REMOVE(child, next_parent); } child->bs = new_bs; if (new_bs) { - assert_bdrv_graph_writable(new_bs); QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent); if (child->klass->attach) { child->klass->attach(child); } } + bdrv_graph_wrunlock(); /* * If the parent was drained through this BdrvChild previously, but new_bs -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> We don't protect bdrv->aio_context with the graph rwlock, so these assertions are not needed Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-13-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_detach_aio_context(BlockDriverState *bs) if (bs->quiesce_counter) { aio_enable_external(bs->aio_context); } - assert_bdrv_graph_writable(bs); bs->aio_context = NULL; } @@ -XXX,XX +XXX,XX @@ static void bdrv_attach_aio_context(BlockDriverState *bs, aio_disable_external(new_context); } - assert_bdrv_graph_writable(bs); bs->aio_context = new_context; if (bs->drv && bs->drv->bdrv_attach_aio_context) { @@ -XXX,XX +XXX,XX @@ static void bdrv_set_aio_context_commit(void *opaque) BlockDriverState *bs = (BlockDriverState *) state->bs; AioContext *new_context = state->new_ctx; AioContext *old_context = bdrv_get_aio_context(bs); - assert_bdrv_graph_writable(bs); /* * Take the old AioContex when detaching it from bs. -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Remove the old assert_bdrv_graph_writable, and replace it with the new version using graph-lock API. See the function documentation for more information. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-14-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block_int-global-state.h | 17 ----------------- include/block/graph-lock.h | 15 +++++++++++++++ block.c | 4 ++-- block/graph-lock.c | 11 +++++++++++ 4 files changed, 28 insertions(+), 19 deletions(-) diff --git a/include/block/block_int-global-state.h b/include/block/block_int-global-state.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-global-state.h +++ b/include/block/block_int-global-state.h @@ -XXX,XX +XXX,XX @@ void bdrv_remove_aio_context_notifier(BlockDriverState *bs, */ void bdrv_drain_all_end_quiesce(BlockDriverState *bs); -/** - * Make sure that the function is running under both drain and BQL. - * The latter protects from concurrent writings - * from the GS API, while the former prevents concurrent reads - * from I/O. - */ -static inline void assert_bdrv_graph_writable(BlockDriverState *bs) -{ - /* - * TODO: this function is incomplete. Because the users of this - * assert lack the necessary drains, check only for BQL. - * Once the necessary drains are added, - * assert also for qatomic_read(&bs->quiesce_counter) > 0 - */ - assert(qemu_in_main_thread()); -} - #endif /* BLOCK_INT_GLOBAL_STATE_H */ diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -XXX,XX +XXX,XX @@ void coroutine_fn bdrv_graph_co_rdunlock(void); void bdrv_graph_rdlock_main_loop(void); void bdrv_graph_rdunlock_main_loop(void); +/* + * assert_bdrv_graph_readable: + * Make sure that the reader is either the main loop, + * or there is at least a reader helding the rdlock. + * In this way an incoming writer is aware of the read and waits. + */ +void assert_bdrv_graph_readable(void); + +/* + * assert_bdrv_graph_writable: + * Make sure that the writer is the main loop and has set @has_writer, + * so that incoming readers will pause. + */ +void assert_bdrv_graph_writable(void); + typedef struct GraphLockable { } GraphLockable; /* diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_attach(BdrvChild *child) { BlockDriverState *bs = child->opaque; - assert_bdrv_graph_writable(bs); + assert_bdrv_graph_writable(); QLIST_INSERT_HEAD(&bs->children, child, next); if (bs->drv->is_filter || (child->role & BDRV_CHILD_FILTERED)) { /* @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_detach(BdrvChild *child) bdrv_backing_detach(child); } - assert_bdrv_graph_writable(bs); + assert_bdrv_graph_writable(); QLIST_REMOVE(child, next); if (child == bs->backing) { assert(child != bs->file); diff --git a/block/graph-lock.c b/block/graph-lock.c index XXXXXXX..XXXXXXX 100644 --- a/block/graph-lock.c +++ b/block/graph-lock.c @@ -XXX,XX +XXX,XX @@ void bdrv_graph_rdunlock_main_loop(void) GLOBAL_STATE_CODE(); assert(!qemu_in_coroutine()); } + +void assert_bdrv_graph_readable(void) +{ + assert(qemu_in_main_thread() || reader_count()); +} + +void assert_bdrv_graph_writable(void) +{ + assert(qemu_in_main_thread()); + assert(qatomic_read(&has_writer)); +} -- 2.38.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-15-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/graph-lock.h | 80 +++++++++++++++++++++++++++++++++----- block/graph-lock.c | 3 ++ 2 files changed, 73 insertions(+), 10 deletions(-) diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -XXX,XX +XXX,XX @@ #define GRAPH_LOCK_H #include "qemu/osdep.h" +#include "qemu/clang-tsa.h" #include "qemu/coroutine.h" @@ -XXX,XX +XXX,XX @@ */ typedef struct BdrvGraphRWlock BdrvGraphRWlock; +/* Dummy lock object to use for Thread Safety Analysis (TSA) */ +typedef struct TSA_CAPABILITY("graph-lock") BdrvGraphLock { +} BdrvGraphLock; + +extern BdrvGraphLock graph_lock; + +/* + * clang doesn't check consistency in locking annotations between forward + * declarations and the function definition. Having the annotation on the + * definition, but not the declaration in a header file, may give the reader + * a false sense of security because the condition actually remains unchecked + * for callers in other source files. + * + * Therefore, as a convention, for public functions, GRAPH_RDLOCK and + * GRAPH_WRLOCK annotations should be present only in the header file. + */ +#define GRAPH_WRLOCK TSA_REQUIRES(graph_lock) +#define GRAPH_RDLOCK TSA_REQUIRES_SHARED(graph_lock) + +/* + * TSA annotations are not part of function types, so checks are defeated when + * using a function pointer. As a workaround, annotate function pointers with + * this macro that will require that the lock is at least taken while reading + * the pointer. In most cases this is equivalent to actually protecting the + * function call. + */ +#define GRAPH_RDLOCK_PTR TSA_GUARDED_BY(graph_lock) +#define GRAPH_WRLOCK_PTR TSA_GUARDED_BY(graph_lock) + /* * register_aiocontext: * Add AioContext @ctx to the list of AioContext. @@ -XXX,XX +XXX,XX @@ void unregister_aiocontext(AioContext *ctx); * This function polls. Callers must not hold the lock of any AioContext other * than the current one. */ -void bdrv_graph_wrlock(void); +void bdrv_graph_wrlock(void) TSA_ACQUIRE(graph_lock) TSA_NO_TSA; /* * bdrv_graph_wrunlock: * Write finished, reset global has_writer to 0 and restart * all readers that are waiting. */ -void bdrv_graph_wrunlock(void); +void bdrv_graph_wrunlock(void) TSA_RELEASE(graph_lock) TSA_NO_TSA; /* * bdrv_graph_co_rdlock: @@ -XXX,XX +XXX,XX @@ void bdrv_graph_wrunlock(void); * loop) to take it and wait that the coroutine ends, so that * we always signal that a reader is running. */ -void coroutine_fn bdrv_graph_co_rdlock(void); +void coroutine_fn TSA_ACQUIRE_SHARED(graph_lock) TSA_NO_TSA +bdrv_graph_co_rdlock(void); /* * bdrv_graph_rdunlock: @@ -XXX,XX +XXX,XX @@ void coroutine_fn bdrv_graph_co_rdlock(void); * If the writer is waiting for reads to finish (has_writer == 1), signal * the writer that we are done via aio_wait_kick() to let it continue. */ -void coroutine_fn bdrv_graph_co_rdunlock(void); +void coroutine_fn TSA_RELEASE_SHARED(graph_lock) TSA_NO_TSA +bdrv_graph_co_rdunlock(void); /* * bdrv_graph_rd{un}lock_main_loop: @@ -XXX,XX +XXX,XX @@ void coroutine_fn bdrv_graph_co_rdunlock(void); * in the main loop. It is just asserting that we are not * in a coroutine and in GLOBAL_STATE_CODE. */ -void bdrv_graph_rdlock_main_loop(void); -void bdrv_graph_rdunlock_main_loop(void); +void TSA_ACQUIRE_SHARED(graph_lock) TSA_NO_TSA +bdrv_graph_rdlock_main_loop(void); + +void TSA_RELEASE_SHARED(graph_lock) TSA_NO_TSA +bdrv_graph_rdunlock_main_loop(void); /* * assert_bdrv_graph_readable: @@ -XXX,XX +XXX,XX @@ void assert_bdrv_graph_readable(void); */ void assert_bdrv_graph_writable(void); +/* + * Calling this function tells TSA that we know that the lock is effectively + * taken even though we cannot prove it (yet) with GRAPH_RDLOCK. This can be + * useful in intermediate stages of a conversion to using the GRAPH_RDLOCK + * macro. + */ +static inline void TSA_ASSERT_SHARED(graph_lock) TSA_NO_TSA +assume_graph_lock(void) +{ +} + typedef struct GraphLockable { } GraphLockable; /* @@ -XXX,XX +XXX,XX @@ typedef struct GraphLockable { } GraphLockable; */ #define GML_OBJ_() (&(GraphLockable) { }) -static inline GraphLockable *graph_lockable_auto_lock(GraphLockable *x) +/* + * This is not marked as TSA_ACQUIRE() because TSA doesn't understand the + * cleanup attribute and would therefore complain that the graph is never + * unlocked. TSA_ASSERT() makes sure that the following calls know that we + * hold the lock while unlocking is left unchecked. + */ +static inline GraphLockable * TSA_ASSERT(graph_lock) TSA_NO_TSA +graph_lockable_auto_lock(GraphLockable *x) { bdrv_graph_co_rdlock(); return x; } -static inline void graph_lockable_auto_unlock(GraphLockable *x) +static inline void TSA_NO_TSA +graph_lockable_auto_unlock(GraphLockable *x) { bdrv_graph_co_rdunlock(); } @@ -XXX,XX +XXX,XX @@ typedef struct GraphLockableMainloop { } GraphLockableMainloop; */ #define GMLML_OBJ_() (&(GraphLockableMainloop) { }) -static inline GraphLockableMainloop * +/* + * This is not marked as TSA_ACQUIRE() because TSA doesn't understand the + * cleanup attribute and would therefore complain that the graph is never + * unlocked. TSA_ASSERT() makes sure that the following calls know that we + * hold the lock while unlocking is left unchecked. + */ +static inline GraphLockableMainloop * TSA_ASSERT(graph_lock) TSA_NO_TSA graph_lockable_auto_lock_mainloop(GraphLockableMainloop *x) { bdrv_graph_rdlock_main_loop(); return x; } -static inline void +static inline void TSA_NO_TSA graph_lockable_auto_unlock_mainloop(GraphLockableMainloop *x) { bdrv_graph_rdunlock_main_loop(); diff --git a/block/graph-lock.c b/block/graph-lock.c index XXXXXXX..XXXXXXX 100644 --- a/block/graph-lock.c +++ b/block/graph-lock.c @@ -XXX,XX +XXX,XX @@ #include "block/block.h" #include "block/block_int.h" +/* Dummy lock object to use for Thread Safety Analysis (TSA) */ +BdrvGraphLock graph_lock; + /* Protects the list of aiocontext and orphaned_reader_count */ static QemuMutex aio_context_list_lock; -- 2.38.1 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-16-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block_int-common.h | 4 ++-- include/block/graph-lock.h | 4 ++-- block.c | 4 ++-- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BdrvChildClass { void (*activate)(BdrvChild *child, Error **errp); int (*inactivate)(BdrvChild *child); - void (*attach)(BdrvChild *child); - void (*detach)(BdrvChild *child); + void GRAPH_WRLOCK_PTR (*attach)(BdrvChild *child); + void GRAPH_WRLOCK_PTR (*detach)(BdrvChild *child); /* * Notifies the parent that the filename of its child has changed (e.g. diff --git a/include/block/graph-lock.h b/include/block/graph-lock.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/graph-lock.h +++ b/include/block/graph-lock.h @@ -XXX,XX +XXX,XX @@ bdrv_graph_rdunlock_main_loop(void); * or there is at least a reader helding the rdlock. * In this way an incoming writer is aware of the read and waits. */ -void assert_bdrv_graph_readable(void); +void GRAPH_RDLOCK assert_bdrv_graph_readable(void); /* * assert_bdrv_graph_writable: * Make sure that the writer is the main loop and has set @has_writer, * so that incoming readers will pause. */ -void assert_bdrv_graph_writable(void); +void GRAPH_WRLOCK assert_bdrv_graph_writable(void); /* * Calling this function tells TSA that we know that the lock is effectively diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static void bdrv_inherited_options(BdrvChildRole role, bool parent_is_format, *child_flags = flags; } -static void bdrv_child_cb_attach(BdrvChild *child) +static void GRAPH_WRLOCK bdrv_child_cb_attach(BdrvChild *child) { BlockDriverState *bs = child->opaque; @@ -XXX,XX +XXX,XX @@ static void bdrv_child_cb_attach(BdrvChild *child) } } -static void bdrv_child_cb_detach(BdrvChild *child) +static void GRAPH_WRLOCK bdrv_child_cb_detach(BdrvChild *child) { BlockDriverState *bs = child->opaque; -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Add co_wrapper_bdrv_rdlock and co_wrapper_mixed_bdrv_rdlock option to the block-coroutine-wrapper.py script. This "_bdrv_rdlock" option takes and releases the graph rdlock when a coroutine function is created. This means that when used together with "_mixed", the function marked with co_wrapper_mixed_bdrv_rdlock will support both coroutine and non-coroutine case, and in the latter case it will create a coroutine that takes and releases the rdlock. When called from a coroutine, the caller must already hold the graph lock. Example: void co_wrapper_mixed_bdrv_rdlock bdrv_f1(); Becomes static void bdrv_co_enter_f1() { bdrv_graph_co_rdlock(); bdrv_co_function(); bdrv_graph_co_rdunlock(); } void bdrv_f1() { if (qemu_in_coroutine) { assume_graph_lock(); bdrv_co_function(); } else { qemu_co_enter(bdrv_co_enter_f1); ... } } When used alone, the function will not work in coroutine context, and when called in non-coroutine context it will create a new coroutine that takes care of taking and releasing the rdlock automatically. Example: void co_wrapper_bdrv_rdlock bdrv_f1(); Becomes static void bdrv_co_enter_f1() { bdrv_graph_co_rdlock(); bdrv_co_function(); bdrv_graph_co_rdunlock(); } void bdrv_f1() { assert(!qemu_in_coroutine()); qemu_co_enter(bdrv_co_enter_f1); ... } About their usage: - co_wrapper does not take the rdlock, so it can be used also outside the block layer. - co_wrapper_mixed will be used by many blk_* functions, since the coroutine function needs to call blk_wait_while_drained() and the rdlock *must* be taken afterwards, otherwise it's a deadlock. In the future this annotation will go away, and blk_* will use co_wrapper directly. - co_wrapper_bdrv_rdlock will be used by BlockDriver callbacks, ideally by all of them in the future. - co_wrapper_mixed_bdrv_rdlock will be used by the remaining functions that are still called by coroutine and non-coroutine context. In the future this annotation will go away, as we will split such mixed functions. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-17-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block-common.h | 9 ++++++++- scripts/block-coroutine-wrapper.py | 12 ++++++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/include/block/block-common.h b/include/block/block-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-common.h +++ b/include/block/block-common.h @@ -XXX,XX +XXX,XX @@ * * Usage: read docs/devel/block-coroutine-wrapper.rst * - * There are 2 kind of specifiers: + * There are 4 kind of specifiers: * - co_wrapper functions can be called by only non-coroutine context, because * they always generate a new coroutine. * - co_wrapper_mixed functions can be called by both coroutine and * non-coroutine context. + * - co_wrapper_bdrv_rdlock are co_wrapper functions but automatically take and + * release the graph rdlock when creating a new coroutine + * - co_wrapper_mixed_bdrv_rdlock are co_wrapper_mixed functions but + * automatically take and release the graph rdlock when creating a new + * coroutine. */ #define co_wrapper #define co_wrapper_mixed +#define co_wrapper_bdrv_rdlock +#define co_wrapper_mixed_bdrv_rdlock #include "block/dirty-bitmap.h" #include "block/blockjob.h" diff --git a/scripts/block-coroutine-wrapper.py b/scripts/block-coroutine-wrapper.py index XXXXXXX..XXXXXXX 100644 --- a/scripts/block-coroutine-wrapper.py +++ b/scripts/block-coroutine-wrapper.py @@ -XXX,XX +XXX,XX @@ def __init__(self, return_type: str, name: str, args: str, self.struct_name = snake_to_camel(self.name) self.args = [ParamDecl(arg.strip()) for arg in args.split(',')] self.create_only_co = 'mixed' not in variant + self.graph_rdlock = 'bdrv_rdlock' in variant subsystem, subname = self.name.split('_', 1) self.co_name = f'{subsystem}_co_{subname}' @@ -XXX,XX +XXX,XX @@ def create_mixed_wrapper(func: FuncDecl) -> str: """ name = func.co_name struct_name = func.struct_name + graph_assume_lock = 'assume_graph_lock();' if func.graph_rdlock else '' + return f"""\ {func.return_type} {func.name}({ func.gen_list('{decl}') }) {{ if (qemu_in_coroutine()) {{ + {graph_assume_lock} return {name}({ func.gen_list('{name}') }); }} else {{ {struct_name} s = {{ @@ -XXX,XX +XXX,XX @@ def gen_wrapper(func: FuncDecl) -> str: name = func.co_name struct_name = func.struct_name + graph_lock='' + graph_unlock='' + if func.graph_rdlock: + graph_lock=' bdrv_graph_co_rdlock();' + graph_unlock=' bdrv_graph_co_rdunlock();' + creation_function = create_mixed_wrapper if func.create_only_co: creation_function = create_co_wrapper @@ -XXX,XX +XXX,XX @@ def gen_wrapper(func: FuncDecl) -> str: {{ {struct_name} *s = opaque; +{graph_lock} s->ret = {name}({ func.gen_list('s->{name}') }); +{graph_unlock} s->poll_state.in_progress = false; aio_wait_kick(); -- 2.38.1 From: Emanuele Giuseppe Esposito <eesposit@redhat.com> Take the rdlock already, before we add the assertions. All these functions either read the graph recursively, or call BlockDriver callbacks that will eventually need to be protected by the graph rdlock. Do it now to all functions together, because many of these recursively call each other. For example, bdrv_co_truncate calls BlockDriver->bdrv_co_truncate, and some driver callbacks implement their own .bdrv_co_truncate by calling bdrv_flush inside. So if bdrv_flush asserts but bdrv_truncate does not take the rdlock yet, the assertion will always fail. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-18-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/coroutines.h | 2 +- include/block/block-io.h | 53 +++++++++++++++++++++++----------------- 2 files changed, 32 insertions(+), 23 deletions(-) diff --git a/block/coroutines.h b/block/coroutines.h index XXXXXXX..XXXXXXX 100644 --- a/block/coroutines.h +++ b/block/coroutines.h @@ -XXX,XX +XXX,XX @@ nbd_co_do_establish_connection(BlockDriverState *bs, bool blocking, * the "I/O or GS" API. */ -int co_wrapper_mixed +int co_wrapper_mixed_bdrv_rdlock bdrv_common_block_status_above(BlockDriverState *bs, BlockDriverState *base, bool include_base, diff --git a/include/block/block-io.h b/include/block/block-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block-io.h +++ b/include/block/block-io.h @@ -XXX,XX +XXX,XX @@ * to catch when they are accidentally called by the wrong API. */ -int co_wrapper_mixed bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, - int64_t bytes, - BdrvRequestFlags flags); +int co_wrapper_mixed_bdrv_rdlock +bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, int64_t bytes, + BdrvRequestFlags flags); + int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); -int co_wrapper_mixed bdrv_pread(BdrvChild *child, int64_t offset, - int64_t bytes, void *buf, - BdrvRequestFlags flags); -int co_wrapper_mixed bdrv_pwrite(BdrvChild *child, int64_t offset, - int64_t bytes, const void *buf, - BdrvRequestFlags flags); -int co_wrapper_mixed bdrv_pwrite_sync(BdrvChild *child, int64_t offset, - int64_t bytes, const void *buf, - BdrvRequestFlags flags); + +int co_wrapper_mixed_bdrv_rdlock +bdrv_pread(BdrvChild *child, int64_t offset, int64_t bytes, void *buf, + BdrvRequestFlags flags); + +int co_wrapper_mixed_bdrv_rdlock +bdrv_pwrite(BdrvChild *child, int64_t offset,int64_t bytes, + const void *buf, BdrvRequestFlags flags); + +int co_wrapper_mixed_bdrv_rdlock +bdrv_pwrite_sync(BdrvChild *child, int64_t offset, int64_t bytes, + const void *buf, BdrvRequestFlags flags); + int coroutine_fn bdrv_co_pwrite_sync(BdrvChild *child, int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags); @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_copy_range(BdrvChild *src, int64_t src_offset, void bdrv_drain(BlockDriverState *bs); -int co_wrapper_mixed +int co_wrapper_mixed_bdrv_rdlock bdrv_truncate(BdrvChild *child, int64_t offset, bool exact, PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); -int co_wrapper_mixed bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, - BdrvCheckMode fix); +int co_wrapper_mixed_bdrv_rdlock +bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); /* Invalidate any cached metadata used by image formats */ -int co_wrapper_mixed bdrv_invalidate_cache(BlockDriverState *bs, - Error **errp); -int co_wrapper_mixed bdrv_flush(BlockDriverState *bs); -int co_wrapper_mixed bdrv_pdiscard(BdrvChild *child, int64_t offset, - int64_t bytes); -int co_wrapper_mixed +int co_wrapper_mixed_bdrv_rdlock +bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); + +int co_wrapper_mixed_bdrv_rdlock bdrv_flush(BlockDriverState *bs); + +int co_wrapper_mixed_bdrv_rdlock +bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); + +int co_wrapper_mixed_bdrv_rdlock bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); -int co_wrapper_mixed + +int co_wrapper_mixed_bdrv_rdlock bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); /** -- 2.38.1 The generated coroutine wrappers already take care to take the lock in the non-coroutine path, and assume that the lock is already taken in the coroutine path. The only thing we need to do for the wrapped function is adding the GRAPH_RDLOCK annotation. Doing so also allows us to mark the corresponding callbacks in BlockDriver as GRAPH_RDLOCK_PTR. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-19-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/coroutines.h | 17 ++++++++++------- include/block/block_int-common.h | 20 +++++++++----------- block.c | 2 ++ block/io.c | 2 ++ 4 files changed, 23 insertions(+), 18 deletions(-) diff --git a/block/coroutines.h b/block/coroutines.h index XXXXXXX..XXXXXXX 100644 --- a/block/coroutines.h +++ b/block/coroutines.h @@ -XXX,XX +XXX,XX @@ * the I/O API. */ -int coroutine_fn bdrv_co_check(BlockDriverState *bs, - BdrvCheckResult *res, BdrvCheckMode fix); -int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp); +int coroutine_fn GRAPH_RDLOCK +bdrv_co_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); + +int coroutine_fn GRAPH_RDLOCK +bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp); int coroutine_fn bdrv_co_common_block_status_above(BlockDriverState *bs, @@ -XXX,XX +XXX,XX @@ bdrv_co_common_block_status_above(BlockDriverState *bs, BlockDriverState **file, int *depth); -int coroutine_fn bdrv_co_readv_vmstate(BlockDriverState *bs, - QEMUIOVector *qiov, int64_t pos); -int coroutine_fn bdrv_co_writev_vmstate(BlockDriverState *bs, - QEMUIOVector *qiov, int64_t pos); +int coroutine_fn GRAPH_RDLOCK +bdrv_co_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); + +int coroutine_fn GRAPH_RDLOCK +bdrv_co_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); int coroutine_fn nbd_co_do_establish_connection(BlockDriverState *bs, bool blocking, diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -XXX,XX +XXX,XX @@ struct BlockDriver { /* * Invalidate any cached meta-data. */ - void coroutine_fn (*bdrv_co_invalidate_cache)(BlockDriverState *bs, - Error **errp); + void coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_invalidate_cache)( + BlockDriverState *bs, Error **errp); /* * Flushes all data for all layers by calling bdrv_co_flush for underlying @@ -XXX,XX +XXX,XX @@ struct BlockDriver { Error **errp); BlockStatsSpecific *(*bdrv_get_specific_stats)(BlockDriverState *bs); - int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs, - QEMUIOVector *qiov, - int64_t pos); - int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs, - QEMUIOVector *qiov, - int64_t pos); + int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_save_vmstate)( + BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); + + int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_load_vmstate)( + BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); /* removable device specific */ bool (*bdrv_is_inserted)(BlockDriverState *bs); @@ -XXX,XX +XXX,XX @@ struct BlockDriver { * Returns 0 for completed check, -errno for internal errors. * The check results are stored in result. */ - int coroutine_fn (*bdrv_co_check)(BlockDriverState *bs, - BdrvCheckResult *result, - BdrvCheckMode fix); + int coroutine_fn GRAPH_RDLOCK_PTR (*bdrv_co_check)( + BlockDriverState *bs, BdrvCheckResult *result, BdrvCheckMode fix); void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event); diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix) { IO_CODE(); + assert_bdrv_graph_readable(); if (bs->drv == NULL) { return -ENOMEDIUM; } @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp) IO_CODE(); assert(!(bs->open_flags & BDRV_O_INACTIVE)); + assert_bdrv_graph_readable(); if (bs->drv->bdrv_co_invalidate_cache) { bs->drv->bdrv_co_invalidate_cache(bs, &local_err); diff --git a/block/io.c b/block/io.c index XXXXXXX..XXXXXXX 100644 --- a/block/io.c +++ b/block/io.c @@ -XXX,XX +XXX,XX @@ bdrv_co_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) BlockDriverState *child_bs = bdrv_primary_bs(bs); int ret; IO_CODE(); + assert_bdrv_graph_readable(); ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ bdrv_co_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos) BlockDriverState *child_bs = bdrv_primary_bs(bs); int ret; IO_CODE(); + assert_bdrv_graph_readable(); ret = bdrv_check_qiov_request(pos, qiov->size, qiov, 0, NULL); if (ret < 0) { -- 2.38.1