The following changes since commit 9514f2648ca05b38e852b490a12b8cd98d5808c1: Merge remote-tracking branch 'remotes/gkurz/tags/for-upstream' into staging (2017-02-28 17:39:49 +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 b2c2832c6140cfe3ddc0de2d77eeb0b77dea8fd3: block: Add Error parameter to bdrv_append() (2017-02-28 20:47:51 +0100) ---------------------------------------------------------------- Block layer patches ---------------------------------------------------------------- Kevin Wolf (44): block: Add op blocker permission constants block: Add Error argument to bdrv_attach_child() block: Let callers request permissions when attaching a child node block: Involve block drivers in permission granting block: Default .bdrv_child_perm() for filter drivers block: Request child permissions in filter drivers block: Default .bdrv_child_perm() for format drivers block: Request child permissions in format drivers vvfat: Implement .bdrv_child_perm() block: Require .bdrv_child_perm() with child nodes block: Request real permissions in bdrv_attach_child() block: Add permissions to BlockBackend block: Add permissions to blk_new() block: Add error parameter to blk_insert_bs() block: Add BDRV_O_RESIZE for blk_new_open() block: Request real permissions in blk_new_open() block: Allow error return in BlockDevOps.change_media_cb() hw/block: Request permissions hw/block: Introduce share-rw qdev property blockjob: Add permissions to block_job_create() block: Add BdrvChildRole.get_parent_desc() block: Include details on permission errors in message block: Add BdrvChildRole.stay_at_node blockjob: Add permissions to block_job_add_bdrv() commit: Use real permissions in commit block job commit: Use real permissions for HMP 'commit' backup: Use real permissions in backup block job block: Fix pending requests check in bdrv_append() block: BdrvChildRole.attach/detach() callbacks block: Allow backing file links in change_parent_backing_link() blockjob: Factor out block_job_remove_all_bdrv() mirror: Use real permissions in mirror/active commit block job stream: Use real permissions in streaming block job mirror: Add filter-node-name to blockdev-mirror commit: Add filter-node-name to block-commit hmp: Request permissions in qemu-io migration/block: Use real permissions nbd/server: Use real permissions for NBD exports tests: Remove FIXME comments block: Pass BdrvChild to bdrv_aligned_preadv/pwritev and copy-on-read block: Assertions for write permissions block: Assertions for resize permission block: Add Error parameter to bdrv_set_backing_hd() block: Add Error parameter to bdrv_append() Markus Armbruster (1): option: Tweak invalid size error message and unbreak iotest 049 Peter Lieven (1): qemu-img: make convert async block.c | 583 ++++++++++++++++++++++++++++++++++----- block/backup.c | 22 +- block/blkdebug.c | 2 + block/blkreplay.c | 1 + block/blkverify.c | 1 + block/block-backend.c | 116 +++++++- block/bochs.c | 1 + block/cloop.c | 1 + block/commit.c | 176 ++++++++++-- block/crypto.c | 1 + block/dmg.c | 1 + block/io.c | 41 +-- block/mirror.c | 237 ++++++++++++++-- block/parallels.c | 4 +- block/qcow.c | 4 +- block/qcow2.c | 19 +- block/qed.c | 4 +- block/quorum.c | 11 +- block/raw-format.c | 1 + block/replication.c | 3 +- block/sheepdog.c | 2 +- block/stream.c | 47 +++- block/vdi.c | 4 +- block/vhdx.c | 4 +- block/vmdk.c | 7 +- block/vpc.c | 4 +- block/vvfat.c | 24 +- blockdev.c | 74 ++++- blockjob.c | 62 ++++- hmp.c | 33 ++- hw/block/block.c | 24 +- hw/block/fdc.c | 28 +- hw/block/m25p80.c | 8 + hw/block/nand.c | 7 + hw/block/nvme.c | 8 +- hw/block/onenand.c | 7 + hw/block/pflash_cfi01.c | 18 +- hw/block/pflash_cfi02.c | 19 +- hw/block/virtio-blk.c | 8 +- hw/core/qdev-properties-system.c | 9 +- hw/ide/core.c | 2 +- hw/ide/qdev.c | 9 +- hw/nvram/spapr_nvram.c | 8 + hw/scsi/scsi-disk.c | 12 +- hw/sd/sd.c | 8 +- hw/usb/dev-storage.c | 6 +- include/block/block.h | 46 ++- include/block/block_int.h | 126 ++++++++- include/block/blockjob.h | 14 +- include/block/blockjob_int.h | 4 +- include/hw/block/block.h | 8 +- include/qemu-io.h | 1 + include/sysemu/block-backend.h | 9 +- migration/block.c | 21 +- nbd/server.c | 16 +- qapi/block-core.json | 16 +- qemu-img-cmds.hx | 4 +- qemu-img.c | 334 +++++++++++++++------- qemu-img.texi | 16 +- qemu-io-cmds.c | 28 ++ tests/qemu-iotests/049.out | 14 +- tests/qemu-iotests/051.pc.out | 6 +- tests/qemu-iotests/055 | 11 +- tests/qemu-iotests/085.out | 2 +- tests/qemu-iotests/141 | 2 +- tests/qemu-iotests/141.out | 4 +- tests/qemu-iotests/172.out | 53 ++++ tests/test-blockjob-txn.c | 6 +- tests/test-blockjob.c | 10 +- tests/test-throttle.c | 7 +- util/qemu-option.c | 2 +- 71 files changed, 2039 insertions(+), 392 deletions(-) From: Peter Lieven <pl@kamp.de> the convert process is currently completely implemented with sync operations. That means it reads one buffer and then writes it. No parallelism and each sync request takes as long as it takes until it is completed. This can be a big performance hit when the convert process reads and writes to devices which do not benefit from kernel readahead or pagecache. In our environment we heavily have the following two use cases when using qemu-img convert. a) reading from NFS and writing to iSCSI for deploying templates b) reading from iSCSI and writing to NFS for backups In both processes we use libiscsi and libnfs so we have no kernel cache. This patch changes the convert process to work with parallel running coroutines which can significantly improve performance for network storage devices: qemu-img (master) nfs -> iscsi 22.8 secs nfs -> ram 11.7 secs ram -> iscsi 12.3 secs qemu-img-async (8 coroutines, in-order write disabled) nfs -> iscsi 11.0 secs nfs -> ram 10.4 secs ram -> iscsi 9.0 secs This patches introduces 2 new cmdline parameters. The -m parameter to specify the number of coroutines running in parallel (defaults to 8). And the -W parameter to allow qemu-img to write to the target out of order rather than sequential. This improves performance as the writes do not have to wait for each other to complete. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- qemu-img-cmds.hx | 4 +- qemu-img.c | 322 ++++++++++++++++++++++++++++++++++++++----------------- qemu-img.texi | 16 ++- 3 files changed, 243 insertions(+), 99 deletions(-) diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx index XXXXXXX..XXXXXXX 100644 --- a/qemu-img-cmds.hx +++ b/qemu-img-cmds.hx @@ -XXX,XX +XXX,XX @@ STEXI ETEXI DEF("convert", img_convert, - "convert [--object objectdef] [--image-opts] [-c] [-p] [-q] [-n] [-f fmt] [-t cache] [-T src_cache] [-O output_fmt] [-o options] [-s snapshot_id_or_name] [-l snapshot_param] [-S sparse_size] filename [filename2 [...]] output_filename") + "convert [--object objectdef] [--image-opts] [-c] [-p] [-q] [-n] [-f fmt] [-t cache] [-T src_cache] [-O output_fmt] [-o options] [-s snapshot_id_or_name] [-l snapshot_param] [-S sparse_size] [-m num_coroutines] [-W] filename [filename2 [...]] output_filename") STEXI -@item convert [--object @var{objectdef}] [--image-opts] [-c] [-p] [-q] [-n] [-f @var{fmt}] [-t @var{cache}] [-T @var{src_cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [--object @var{objectdef}] [--image-opts] [-c] [-p] [-q] [-n] [-f @var{fmt}] [-t @var{cache}] [-T @var{src_cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-S @var{sparse_size}] [-m @var{num_coroutines}] [-W] @var{filename} [@var{filename2} [...]] @var{output_filename} ETEXI DEF("dd", img_dd, 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 void QEMU_NORETURN help(void) " kinds of errors, with a higher risk of choosing the wrong fix or\n" " hiding corruption that has already occurred.\n" "\n" + "Parameters to convert subcommand:\n" + " '-m' specifies how many coroutines work in parallel during the convert\n" + " process (defaults to 8)\n" + " '-W' allow to write to the target out of order rather than sequential\n" + "\n" "Parameters to snapshot subcommand:\n" " 'snapshot' is the name of the snapshot to create, apply or delete\n" " '-a' applies a snapshot (revert disk to saved state)\n" @@ -XXX,XX +XXX,XX @@ enum ImgConvertBlockStatus { BLK_BACKING_FILE, }; +#define MAX_COROUTINES 16 + typedef struct ImgConvertState { BlockBackend **src; int64_t *src_sectors; - int src_cur, src_num; - int64_t src_cur_offset; + int src_num; int64_t total_sectors; int64_t allocated_sectors; + int64_t allocated_done; + int64_t sector_num; + int64_t wr_offs; enum ImgConvertBlockStatus status; int64_t sector_next_status; BlockBackend *target; bool has_zero_init; bool compressed; bool target_has_backing; + bool wr_in_order; int min_sparse; size_t cluster_sectors; size_t buf_sectors; + int num_coroutines; + int running_coroutines; + Coroutine *co[MAX_COROUTINES]; + int64_t wait_sector_num[MAX_COROUTINES]; + CoMutex lock; + int ret; } ImgConvertState; -static void convert_select_part(ImgConvertState *s, int64_t sector_num) +static void convert_select_part(ImgConvertState *s, int64_t sector_num, + int *src_cur, int64_t *src_cur_offset) { - assert(sector_num >= s->src_cur_offset); - while (sector_num - s->src_cur_offset >= s->src_sectors[s->src_cur]) { - s->src_cur_offset += s->src_sectors[s->src_cur]; - s->src_cur++; - assert(s->src_cur < s->src_num); + *src_cur = 0; + *src_cur_offset = 0; + while (sector_num - *src_cur_offset >= s->src_sectors[*src_cur]) { + *src_cur_offset += s->src_sectors[*src_cur]; + (*src_cur)++; + assert(*src_cur < s->src_num); } } static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) { - int64_t ret; - int n; + int64_t ret, src_cur_offset; + int n, src_cur; - convert_select_part(s, sector_num); + convert_select_part(s, sector_num, &src_cur, &src_cur_offset); assert(s->total_sectors > sector_num); n = MIN(s->total_sectors - sector_num, BDRV_REQUEST_MAX_SECTORS); if (s->sector_next_status <= sector_num) { BlockDriverState *file; - ret = bdrv_get_block_status(blk_bs(s->src[s->src_cur]), - sector_num - s->src_cur_offset, + ret = bdrv_get_block_status(blk_bs(s->src[src_cur]), + sector_num - src_cur_offset, n, &n, &file); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) /* Check block status of the backing file chain to avoid * needlessly reading zeroes and limiting the iteration to the * buffer size */ - ret = bdrv_get_block_status_above(blk_bs(s->src[s->src_cur]), NULL, - sector_num - s->src_cur_offset, + ret = bdrv_get_block_status_above(blk_bs(s->src[src_cur]), NULL, + sector_num - src_cur_offset, n, &n, &file); if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) return n; } -static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors, - uint8_t *buf) +static int coroutine_fn convert_co_read(ImgConvertState *s, int64_t sector_num, + int nb_sectors, uint8_t *buf) { - int n; - int ret; + int n, ret; + QEMUIOVector qiov; + struct iovec iov; assert(nb_sectors <= s->buf_sectors); while (nb_sectors > 0) { BlockBackend *blk; - int64_t bs_sectors; + int src_cur; + int64_t bs_sectors, src_cur_offset; /* In the case of compression with multiple source files, we can get a * nb_sectors that spreads into the next part. So we must be able to * read across multiple BDSes for one convert_read() call. */ - convert_select_part(s, sector_num); - blk = s->src[s->src_cur]; - bs_sectors = s->src_sectors[s->src_cur]; - - n = MIN(nb_sectors, bs_sectors - (sector_num - s->src_cur_offset)); - ret = blk_pread(blk, - (sector_num - s->src_cur_offset) << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS); + convert_select_part(s, sector_num, &src_cur, &src_cur_offset); + blk = s->src[src_cur]; + bs_sectors = s->src_sectors[src_cur]; + + n = MIN(nb_sectors, bs_sectors - (sector_num - src_cur_offset)); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_preadv( + blk, (sector_num - src_cur_offset) << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, 0); if (ret < 0) { return ret; } @@ -XXX,XX +XXX,XX @@ static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors, return 0; } -static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, - const uint8_t *buf) + +static int coroutine_fn convert_co_write(ImgConvertState *s, int64_t sector_num, + int nb_sectors, uint8_t *buf, + enum ImgConvertBlockStatus status) { int ret; + QEMUIOVector qiov; + struct iovec iov; while (nb_sectors > 0) { int n = nb_sectors; - - switch (s->status) { + switch (status) { case BLK_BACKING_FILE: /* If we have a backing file, leave clusters unallocated that are * unallocated in the source image, so that the backing file is @@ -XXX,XX +XXX,XX @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, break; } - ret = blk_pwrite_compressed(s->target, - sector_num << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_pwritev(s->target, sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, + BDRV_REQ_WRITE_COMPRESSED); if (ret < 0) { return ret; } @@ -XXX,XX +XXX,XX @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, if (!s->min_sparse || is_allocated_sectors_min(buf, n, &n, s->min_sparse)) { - ret = blk_pwrite(s->target, sector_num << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS, 0); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_pwritev(s->target, sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, 0); if (ret < 0) { return ret; } @@ -XXX,XX +XXX,XX @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, if (s->has_zero_init) { break; } - ret = blk_pwrite_zeroes(s->target, sector_num << BDRV_SECTOR_BITS, - n << BDRV_SECTOR_BITS, 0); + ret = blk_co_pwrite_zeroes(s->target, + sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, 0); if (ret < 0) { return ret; } @@ -XXX,XX +XXX,XX @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, return 0; } -static int convert_do_copy(ImgConvertState *s) +static void coroutine_fn convert_co_do_copy(void *opaque) { + ImgConvertState *s = opaque; uint8_t *buf = NULL; - int64_t sector_num, allocated_done; - int ret; - int n; + int ret, i; + int index = -1; + + for (i = 0; i < s->num_coroutines; i++) { + if (s->co[i] == qemu_coroutine_self()) { + index = i; + break; + } + } + assert(index >= 0); + + s->running_coroutines++; + buf = blk_blockalign(s->target, s->buf_sectors * BDRV_SECTOR_SIZE); + + while (1) { + int n; + int64_t sector_num; + enum ImgConvertBlockStatus status; + + qemu_co_mutex_lock(&s->lock); + if (s->ret != -EINPROGRESS || s->sector_num >= s->total_sectors) { + qemu_co_mutex_unlock(&s->lock); + goto out; + } + n = convert_iteration_sectors(s, s->sector_num); + if (n < 0) { + qemu_co_mutex_unlock(&s->lock); + s->ret = n; + goto out; + } + /* save current sector and allocation status to local variables */ + sector_num = s->sector_num; + status = s->status; + if (!s->min_sparse && s->status == BLK_ZERO) { + n = MIN(n, s->buf_sectors); + } + /* increment global sector counter so that other coroutines can + * already continue reading beyond this request */ + s->sector_num += n; + qemu_co_mutex_unlock(&s->lock); + + if (status == BLK_DATA || (!s->min_sparse && status == BLK_ZERO)) { + s->allocated_done += n; + qemu_progress_print(100.0 * s->allocated_done / + s->allocated_sectors, 0); + } + + if (status == BLK_DATA) { + ret = convert_co_read(s, sector_num, n, buf); + if (ret < 0) { + error_report("error while reading sector %" PRId64 + ": %s", sector_num, strerror(-ret)); + s->ret = ret; + goto out; + } + } else if (!s->min_sparse && status == BLK_ZERO) { + status = BLK_DATA; + memset(buf, 0x00, n * BDRV_SECTOR_SIZE); + } + + if (s->wr_in_order) { + /* keep writes in order */ + while (s->wr_offs != sector_num) { + if (s->ret != -EINPROGRESS) { + goto out; + } + s->wait_sector_num[index] = sector_num; + qemu_coroutine_yield(); + } + s->wait_sector_num[index] = -1; + } + + ret = convert_co_write(s, sector_num, n, buf, status); + if (ret < 0) { + error_report("error while writing sector %" PRId64 + ": %s", sector_num, strerror(-ret)); + s->ret = ret; + goto out; + } + + if (s->wr_in_order) { + /* reenter the coroutine that might have waited + * for this write to complete */ + s->wr_offs = sector_num + n; + for (i = 0; i < s->num_coroutines; i++) { + if (s->co[i] && s->wait_sector_num[i] == s->wr_offs) { + /* + * A -> B -> A cannot occur because A has + * s->wait_sector_num[i] == -1 during A -> B. Therefore + * B will never enter A during this time window. + */ + qemu_coroutine_enter(s->co[i]); + break; + } + } + } + } + +out: + qemu_vfree(buf); + s->co[index] = NULL; + s->running_coroutines--; + if (!s->running_coroutines && s->ret == -EINPROGRESS) { + /* the convert job finished successfully */ + s->ret = 0; + } +} + +static int convert_do_copy(ImgConvertState *s) +{ + int ret, i, n; + int64_t sector_num = 0; /* Check whether we have zero initialisation or can get it efficiently */ s->has_zero_init = s->min_sparse && !s->target_has_backing @@ -XXX,XX +XXX,XX @@ static int convert_do_copy(ImgConvertState *s) if (s->compressed) { if (s->cluster_sectors <= 0 || s->cluster_sectors > s->buf_sectors) { error_report("invalid cluster size"); - ret = -EINVAL; - goto fail; + return -EINVAL; } s->buf_sectors = s->cluster_sectors; } - buf = blk_blockalign(s->target, s->buf_sectors * BDRV_SECTOR_SIZE); - /* Calculate allocated sectors for progress */ - s->allocated_sectors = 0; - sector_num = 0; while (sector_num < s->total_sectors) { n = convert_iteration_sectors(s, sector_num); if (n < 0) { - ret = n; - goto fail; + return n; } if (s->status == BLK_DATA || (!s->min_sparse && s->status == BLK_ZERO)) { @@ -XXX,XX +XXX,XX @@ static int convert_do_copy(ImgConvertState *s) } /* Do the copy */ - s->src_cur = 0; - s->src_cur_offset = 0; s->sector_next_status = 0; + s->ret = -EINPROGRESS; - sector_num = 0; - allocated_done = 0; - - while (sector_num < s->total_sectors) { - n = convert_iteration_sectors(s, sector_num); - if (n < 0) { - ret = n; - goto fail; - } - if (s->status == BLK_DATA || (!s->min_sparse && s->status == BLK_ZERO)) - { - allocated_done += n; - qemu_progress_print(100.0 * allocated_done / s->allocated_sectors, - 0); - } - - if (s->status == BLK_DATA) { - ret = convert_read(s, sector_num, n, buf); - if (ret < 0) { - error_report("error while reading sector %" PRId64 - ": %s", sector_num, strerror(-ret)); - goto fail; - } - } else if (!s->min_sparse && s->status == BLK_ZERO) { - n = MIN(n, s->buf_sectors); - memset(buf, 0, n * BDRV_SECTOR_SIZE); - s->status = BLK_DATA; - } - - ret = convert_write(s, sector_num, n, buf); - if (ret < 0) { - error_report("error while writing sector %" PRId64 - ": %s", sector_num, strerror(-ret)); - goto fail; - } + qemu_co_mutex_init(&s->lock); + for (i = 0; i < s->num_coroutines; i++) { + s->co[i] = qemu_coroutine_create(convert_co_do_copy, s); + s->wait_sector_num[i] = -1; + qemu_coroutine_enter(s->co[i]); + } - sector_num += n; + while (s->ret == -EINPROGRESS) { + main_loop_wait(false); } - if (s->compressed) { + if (s->compressed && !s->ret) { /* signal EOF to align */ ret = blk_pwrite_compressed(s->target, 0, NULL, 0); if (ret < 0) { - goto fail; + return ret; } } - ret = 0; -fail: - qemu_vfree(buf); - return ret; + return s->ret; } static int img_convert(int argc, char **argv) @@ -XXX,XX +XXX,XX @@ static int img_convert(int argc, char **argv) QemuOpts *sn_opts = NULL; ImgConvertState state; bool image_opts = false; + bool wr_in_order = true; + long num_coroutines = 8; fmt = NULL; out_fmt = "raw"; @@ -XXX,XX +XXX,XX @@ static int img_convert(int argc, char **argv) {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS}, {0, 0, 0, 0} }; - c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qn", + c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qnm:W", long_options, NULL); if (c == -1) { break; @@ -XXX,XX +XXX,XX @@ static int img_convert(int argc, char **argv) case 'n': skip_create = 1; break; + case 'm': + if (qemu_strtol(optarg, NULL, 0, &num_coroutines) || + num_coroutines < 1 || num_coroutines > MAX_COROUTINES) { + error_report("Invalid number of coroutines. Allowed number of" + " coroutines is between 1 and %d", MAX_COROUTINES); + ret = -1; + goto fail_getopt; + } + break; + case 'W': + wr_in_order = false; + break; case OPTION_OBJECT: opts = qemu_opts_parse_noisily(&qemu_object_opts, optarg, true); @@ -XXX,XX +XXX,XX @@ static int img_convert(int argc, char **argv) goto fail_getopt; } + if (!wr_in_order && compress) { + error_report("Out of order write and compress are mutually exclusive"); + ret = -1; + goto fail_getopt; + } + /* Initialize before goto out */ if (quiet) { progress = 0; @@ -XXX,XX +XXX,XX @@ static int img_convert(int argc, char **argv) .min_sparse = min_sparse, .cluster_sectors = cluster_sectors, .buf_sectors = bufsectors, + .wr_in_order = wr_in_order, + .num_coroutines = num_coroutines, }; ret = convert_do_copy(&state); diff --git a/qemu-img.texi b/qemu-img.texi index XXXXXXX..XXXXXXX 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -XXX,XX +XXX,XX @@ Parameters to convert subcommand: @item -n Skip the creation of the target volume +@item -m +Number of parallel coroutines for the convert process +@item -W +Allow out-of-order writes to the destination. This option improves performance, +but is only recommended for preallocated devices like host devices or other +raw block devices. @end table Parameters to dd subcommand: @@ -XXX,XX +XXX,XX @@ Error on reading data @end table -@item convert [-c] [-p] [-n] [-f @var{fmt}] [-t @var{cache}] [-T @var{src_cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [-c] [-p] [-n] [-f @var{fmt}] [-t @var{cache}] [-T @var{src_cache}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_id_or_name}] [-l @var{snapshot_param}] [-m @var{num_coroutines}] [-W] [-S @var{sparse_size}] @var{filename} [@var{filename2} [...]] @var{output_filename} Convert the disk image @var{filename} or a snapshot @var{snapshot_param}(@var{snapshot_id_or_name} is deprecated) to disk image @var{output_filename} using format @var{output_fmt}. It can be optionally compressed (@code{-c} @@ -XXX,XX +XXX,XX @@ skipped. This is useful for formats such as @code{rbd} if the target volume has already been created with site specific options that cannot be supplied through qemu-img. +Out of order writes can be enabled with @code{-W} to improve performance. +This is only recommended for preallocated devices like host devices or other +raw block devices. Out of order write does not work in combination with +creating compressed images. + +@var{num_coroutines} specifies how many coroutines work in parallel during +the convert process (defaults to 8). + @item dd [-f @var{fmt}] [-O @var{output_fmt}] [bs=@var{block_size}] [count=@var{blocks}] [skip=@var{blocks}] if=@var{input} of=@var{output} Dd copies from @var{input} file to @var{output} file converting it from -- 1.8.3.1 From: Markus Armbruster <armbru@redhat.com> Commit 75cdcd1 neglected to update tests/qemu-iotests/049.out, and made the error message for negative size worse. Fix that. Reported-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/049.out | 14 +++++++++----- util/qemu-option.c | 2 +- 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/049.out +++ b/tests/qemu-iotests/049.out @@ -XXX,XX +XXX,XX @@ qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1024 qemu-img: Image size must be less than 8 EiB! qemu-img create -f qcow2 -o size=-1024 TEST_DIR/t.qcow2 -qemu-img: Parameter 'size' expects a non-negative number below 2^64 +qemu-img: Value '-1024' is out of range for parameter 'size' qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2' qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- -1k qemu-img: Image size must be less than 8 EiB! qemu-img create -f qcow2 -o size=-1k TEST_DIR/t.qcow2 -qemu-img: Parameter 'size' expects a non-negative number below 2^64 +qemu-img: Value '-1k' is out of range for parameter 'size' qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2' qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- 1kilobyte @@ -XXX,XX +XXX,XX @@ qemu-img: Invalid image size specified! You may use k, M, G, T, P or E suffixes qemu-img: kilobytes, megabytes, gigabytes, terabytes, petabytes and exabytes. qemu-img create -f qcow2 -o size=1kilobyte TEST_DIR/t.qcow2 -Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16 +qemu-img: Parameter 'size' expects a non-negative number below 2^64 +Optional suffix k, M, G, T, P or E means kilo-, mega-, giga-, tera-, peta- +and exabytes, respectively. +qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2' qemu-img create -f qcow2 TEST_DIR/t.qcow2 -- foobar qemu-img: Invalid image size specified! You may use k, M, G, T, P or E suffixes for qemu-img: kilobytes, megabytes, gigabytes, terabytes, petabytes and exabytes. qemu-img create -f qcow2 -o size=foobar TEST_DIR/t.qcow2 -qemu-img: Parameter 'size' expects a size -You may use k, M, G or T suffixes for kilobytes, megabytes, gigabytes and terabytes. +qemu-img: Parameter 'size' expects a non-negative number below 2^64 +Optional suffix k, M, G, T, P or E means kilo-, mega-, giga-, tera-, peta- +and exabytes, respectively. qemu-img: TEST_DIR/t.qcow2: Invalid options for file format 'qcow2' == Check correct interpretation of suffixes for cluster size == 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 @@ void parse_option_size(const char *name, const char *value, err = qemu_strtosz(value, NULL, &size); if (err == -ERANGE) { - error_setg(errp, "Value '%s' is too large for parameter '%s'", + error_setg(errp, "Value '%s' is out of range for parameter '%s'", value, name); return; } -- 1.8.3.1 This patch defines the permission categories that will be used by the new op blocker system. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- include/block/block.h | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) 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 enum BlockOpType { BLOCK_OP_TYPE_MAX, } BlockOpType; +/* Block node permission constants */ +enum { + /** + * A user that has the "permission" of consistent reads is guaranteed that + * their view of the contents of the block device is complete and + * self-consistent, representing the contents of a disk at a specific + * point. + * + * For most block devices (including their backing files) this is true, but + * the property cannot be maintained in a few situations like for + * intermediate nodes of a commit block job. + */ + BLK_PERM_CONSISTENT_READ = 0x01, + + /** This permission is required to change the visible disk contents. */ + BLK_PERM_WRITE = 0x02, + + /** + * This permission (which is weaker than BLK_PERM_WRITE) is both enough and + * required for writes to the block node when the caller promises that + * the visible disk content doesn't change. + */ + BLK_PERM_WRITE_UNCHANGED = 0x04, + + /** This permission is required to change the size of a block node. */ + BLK_PERM_RESIZE = 0x08, + + /** + * This permission is required to change the node that this BdrvChild + * points to. + */ + BLK_PERM_GRAPH_MOD = 0x10, + + BLK_PERM_ALL = 0x1f, +}; + /* disk I/O throttling */ void bdrv_init(void); void bdrv_init_with_whitelist(void); -- 1.8.3.1 It will have to return an error soon, so prepare the callers for it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 16 +++++++++++++--- block/quorum.c | 9 ++++++++- include/block/block.h | 3 ++- 3 files changed, 23 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 @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, BlockDriverState *child_bs, const char *child_name, - const BdrvChildRole *child_role) + const BdrvChildRole *child_role, + Error **errp) { BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role, parent_bs); @@ -XXX,XX +XXX,XX @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) bs->backing = NULL; goto out; } - bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing); + /* FIXME Error handling */ + bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, + &error_abort); bs->open_flags &= ~BDRV_O_NO_BACKING; pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename); pstrcpy(bs->backing_format, sizeof(bs->backing_format), @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_open_child(const char *filename, const BdrvChildRole *child_role, bool allow_none, Error **errp) { + BdrvChild *c; BlockDriverState *bs; bs = bdrv_open_child_bs(filename, options, bdref_key, parent, child_role, @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_open_child(const char *filename, return NULL; } - return bdrv_attach_child(parent, bs, bdref_key, child_role); + c = bdrv_attach_child(parent, bs, bdref_key, child_role, errp); + if (!c) { + bdrv_unref(bs); + return NULL; + } + + return c; } static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, 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, /* We can safely add the child now */ bdrv_ref(child_bs); - child = bdrv_attach_child(bs, child_bs, indexstr, &child_format); + + child = bdrv_attach_child(bs, child_bs, indexstr, &child_format, errp); + if (child == NULL) { + s->next_child_index--; + bdrv_unref(child_bs); + goto out; + } s->children = g_renew(BdrvChild *, s->children, s->num_children + 1); s->children[s->num_children++] = child; +out: bdrv_drained_end(bs); } 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 @@ void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, BlockDriverState *child_bs, const char *child_name, - const BdrvChildRole *child_role); + const BdrvChildRole *child_role, + Error **errp); bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); -- 1.8.3.1 When attaching a node as a child to a new parent, the required and shared permissions for this parent are checked against all other parents of the node now, and an error is returned if there is a conflict. This allows error returns to a function that previously always succeeded, and the same is true for quite a few callers and their callers. Converting all of them within the same patch would be too much, so for now everyone tells that they don't need any permissions and allow everyone else to do anything. This way we can use &error_abort initially and convert caller by caller to pass actual permission requirements and implement error handling. All these places are marked with FIXME comments and it will be the job of the next patches to clean them up again. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 66 +++++++++++++++++++++++++++++++++++++++++------ block/block-backend.c | 8 ++++-- include/block/block_int.h | 15 ++++++++++- 3 files changed, 78 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 @@ static int bdrv_fill_options(QDict **options, const char *filename, return 0; } +static int bdrv_check_update_perm(BlockDriverState *bs, uint64_t new_used_perm, + uint64_t new_shared_perm, + BdrvChild *ignore_child, Error **errp) +{ + BdrvChild *c; + + /* There is no reason why anyone couldn't tolerate write_unchanged */ + assert(new_shared_perm & BLK_PERM_WRITE_UNCHANGED); + + QLIST_FOREACH(c, &bs->parents, next_parent) { + if (c == ignore_child) { + continue; + } + + if ((new_used_perm & c->shared_perm) != new_used_perm || + (c->perm & new_shared_perm) != c->perm) + { + const char *user = NULL; + if (c->role->get_name) { + user = c->role->get_name(c); + if (user && !*user) { + user = NULL; + } + } + error_setg(errp, "Conflicts with %s", user ?: "another operation"); + return -EPERM; + } + } + + return 0; +} + static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs) { BlockDriverState *old_bs = child->bs; @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs) BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, const char *child_name, const BdrvChildRole *child_role, - void *opaque) + uint64_t perm, uint64_t shared_perm, + void *opaque, Error **errp) { - BdrvChild *child = g_new(BdrvChild, 1); + BdrvChild *child; + int ret; + + ret = bdrv_check_update_perm(child_bs, perm, shared_perm, NULL, errp); + if (ret < 0) { + return NULL; + } + + child = g_new(BdrvChild, 1); *child = (BdrvChild) { - .bs = NULL, - .name = g_strdup(child_name), - .role = child_role, - .opaque = opaque, + .bs = NULL, + .name = g_strdup(child_name), + .role = child_role, + .perm = perm, + .shared_perm = shared_perm, + .opaque = opaque, }; bdrv_replace_child(child, child_bs); @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, const BdrvChildRole *child_role, Error **errp) { - BdrvChild *child = bdrv_root_attach_child(child_bs, child_name, child_role, - parent_bs); + BdrvChild *child; + + /* FIXME Use real permissions */ + child = bdrv_root_attach_child(child_bs, child_name, child_role, + 0, BLK_PERM_ALL, parent_bs, errp); + if (child == NULL) { + return NULL; + } + QLIST_INSERT_HEAD(&parent_bs->children, child, next); return 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 @@ BlockBackend *blk_new_open(const char *filename, const char *reference, return NULL; } - blk->root = bdrv_root_attach_child(bs, "root", &child_root, blk); + /* FIXME Use real permissions */ + blk->root = bdrv_root_attach_child(bs, "root", &child_root, + 0, BLK_PERM_ALL, blk, &error_abort); return blk; } @@ -XXX,XX +XXX,XX @@ void blk_remove_bs(BlockBackend *blk) void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) { bdrv_ref(bs); - blk->root = bdrv_root_attach_child(bs, "root", &child_root, blk); + /* FIXME Use real permissions */ + blk->root = bdrv_root_attach_child(bs, "root", &child_root, + 0, BLK_PERM_ALL, blk, &error_abort); notifier_list_notify(&blk->insert_bs_notifiers, blk); if (blk->public.throttle_state) { 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 @@ struct BdrvChild { char *name; const BdrvChildRole *role; void *opaque; + + /** + * Granted permissions for operating on this BdrvChild (BLK_PERM_* bitmask) + */ + uint64_t perm; + + /** + * Permissions that can still be granted to other users of @bs while this + * BdrvChild is still attached to it. (BLK_PERM_* bitmask) + */ + uint64_t shared_perm; + QLIST_ENTRY(BdrvChild) next; QLIST_ENTRY(BdrvChild) next_parent; }; @@ -XXX,XX +XXX,XX @@ void hmp_drive_add_node(Monitor *mon, const char *optstr); BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, const char *child_name, const BdrvChildRole *child_role, - void *opaque); + uint64_t perm, uint64_t shared_perm, + void *opaque, Error **errp); void bdrv_root_unref_child(BdrvChild *child); const char *bdrv_get_parent_name(const BlockDriverState *bs); -- 1.8.3.1 In many cases, the required permissions of one node on its children depend on what its parents require from it. For example, the raw format or most filter drivers only need to request consistent reads if that's something that one of their parents wants. In order to achieve this, this patch introduces two new BlockDriver callbacks. The first one lets drivers first check (recursively) whether the requested permissions can be set; the second one actually sets the new permission bitmask. Also add helper functions that drivers can use in their implementation of the callbacks to update their permissions on a specific child. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 206 +++++++++++++++++++++++++++++++++++++++++++++- include/block/block_int.h | 61 ++++++++++++++ 2 files changed, 263 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 @@ static int bdrv_fill_options(QDict **options, const char *filename, return 0; } +/* + * Check whether permissions on this node can be changed in a way that + * @cumulative_perms and @cumulative_shared_perms are the new cumulative + * permissions of all its parents. This involves checking whether all necessary + * permission changes to child nodes can be performed. + * + * A call to this function must always be followed by a call to bdrv_set_perm() + * or bdrv_abort_perm_update(). + */ +static int bdrv_check_perm(BlockDriverState *bs, uint64_t cumulative_perms, + uint64_t cumulative_shared_perms, Error **errp) +{ + BlockDriver *drv = bs->drv; + BdrvChild *c; + int ret; + + /* Write permissions never work with read-only images */ + if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && + bdrv_is_read_only(bs)) + { + error_setg(errp, "Block node is read-only"); + return -EPERM; + } + + /* Check this node */ + if (!drv) { + return 0; + } + + if (drv->bdrv_check_perm) { + return drv->bdrv_check_perm(bs, cumulative_perms, + cumulative_shared_perms, errp); + } + + /* Drivers may not have .bdrv_child_perm() */ + if (!drv->bdrv_child_perm) { + return 0; + } + + /* Check all children */ + QLIST_FOREACH(c, &bs->children, next) { + uint64_t cur_perm, cur_shared; + drv->bdrv_child_perm(bs, c, c->role, + cumulative_perms, cumulative_shared_perms, + &cur_perm, &cur_shared); + ret = bdrv_child_check_perm(c, cur_perm, cur_shared, errp); + if (ret < 0) { + return ret; + } + } + + return 0; +} + +/* + * Notifies drivers that after a previous bdrv_check_perm() call, the + * permission update is not performed and any preparations made for it (e.g. + * taken file locks) need to be undone. + * + * This function recursively notifies all child nodes. + */ +static void bdrv_abort_perm_update(BlockDriverState *bs) +{ + BlockDriver *drv = bs->drv; + BdrvChild *c; + + if (!drv) { + return; + } + + if (drv->bdrv_abort_perm_update) { + drv->bdrv_abort_perm_update(bs); + } + + QLIST_FOREACH(c, &bs->children, next) { + bdrv_child_abort_perm_update(c); + } +} + +static void bdrv_set_perm(BlockDriverState *bs, uint64_t cumulative_perms, + uint64_t cumulative_shared_perms) +{ + BlockDriver *drv = bs->drv; + BdrvChild *c; + + if (!drv) { + return; + } + + /* Update this node */ + if (drv->bdrv_set_perm) { + drv->bdrv_set_perm(bs, cumulative_perms, cumulative_shared_perms); + } + + /* Drivers may not have .bdrv_child_perm() */ + if (!drv->bdrv_child_perm) { + return; + } + + /* Update all children */ + QLIST_FOREACH(c, &bs->children, next) { + uint64_t cur_perm, cur_shared; + drv->bdrv_child_perm(bs, c, c->role, + cumulative_perms, cumulative_shared_perms, + &cur_perm, &cur_shared); + bdrv_child_set_perm(c, cur_perm, cur_shared); + } +} + +static void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, + uint64_t *shared_perm) +{ + BdrvChild *c; + uint64_t cumulative_perms = 0; + uint64_t cumulative_shared_perms = BLK_PERM_ALL; + + QLIST_FOREACH(c, &bs->parents, next_parent) { + cumulative_perms |= c->perm; + cumulative_shared_perms &= c->shared_perm; + } + + *perm = cumulative_perms; + *shared_perm = cumulative_shared_perms; +} + +/* + * Checks whether a new reference to @bs can be added if the new user requires + * @new_used_perm/@new_shared_perm as its permissions. If @ignore_child is set, + * this old reference is ignored in the calculations; this allows checking + * permission updates for an existing reference. + * + * Needs to be followed by a call to either bdrv_set_perm() or + * bdrv_abort_perm_update(). */ static int bdrv_check_update_perm(BlockDriverState *bs, uint64_t new_used_perm, uint64_t new_shared_perm, BdrvChild *ignore_child, Error **errp) { BdrvChild *c; + uint64_t cumulative_perms = new_used_perm; + uint64_t cumulative_shared_perms = new_shared_perm; /* There is no reason why anyone couldn't tolerate write_unchanged */ assert(new_shared_perm & BLK_PERM_WRITE_UNCHANGED); @@ -XXX,XX +XXX,XX @@ static int bdrv_check_update_perm(BlockDriverState *bs, uint64_t new_used_perm, error_setg(errp, "Conflicts with %s", user ?: "another operation"); return -EPERM; } + + cumulative_perms |= c->perm; + cumulative_shared_perms &= c->shared_perm; } + return bdrv_check_perm(bs, cumulative_perms, cumulative_shared_perms, errp); +} + +/* Needs to be followed by a call to either bdrv_child_set_perm() or + * bdrv_child_abort_perm_update(). */ +int bdrv_child_check_perm(BdrvChild *c, uint64_t perm, uint64_t shared, + Error **errp) +{ + return bdrv_check_update_perm(c->bs, perm, shared, c, errp); +} + +void bdrv_child_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared) +{ + uint64_t cumulative_perms, cumulative_shared_perms; + + c->perm = perm; + c->shared_perm = shared; + + bdrv_get_cumulative_perm(c->bs, &cumulative_perms, + &cumulative_shared_perms); + bdrv_set_perm(c->bs, cumulative_perms, cumulative_shared_perms); +} + +void bdrv_child_abort_perm_update(BdrvChild *c) +{ + bdrv_abort_perm_update(c->bs); +} + +int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, + Error **errp) +{ + int ret; + + ret = bdrv_child_check_perm(c, perm, shared, errp); + if (ret < 0) { + bdrv_child_abort_perm_update(c); + return ret; + } + + bdrv_child_set_perm(c, perm, shared); + return 0; } -static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs) +static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, + bool check_new_perm) { BlockDriverState *old_bs = child->bs; + uint64_t perm, shared_perm; if (old_bs) { if (old_bs->quiesce_counter && child->role->drained_end) { child->role->drained_end(child); } QLIST_REMOVE(child, next_parent); + + /* Update permissions for old node. This is guaranteed to succeed + * because we're just taking a parent away, so we're loosening + * restrictions. */ + bdrv_get_cumulative_perm(old_bs, &perm, &shared_perm); + bdrv_check_perm(old_bs, perm, shared_perm, &error_abort); + bdrv_set_perm(old_bs, perm, shared_perm); } child->bs = new_bs; @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs) if (new_bs->quiesce_counter && child->role->drained_begin) { child->role->drained_begin(child); } + + bdrv_get_cumulative_perm(new_bs, &perm, &shared_perm); + if (check_new_perm) { + bdrv_check_perm(new_bs, perm, shared_perm, &error_abort); + } + bdrv_set_perm(new_bs, perm, shared_perm); } } @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, ret = bdrv_check_update_perm(child_bs, perm, shared_perm, NULL, errp); if (ret < 0) { + bdrv_abort_perm_update(child_bs); return NULL; } @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, .opaque = opaque, }; - bdrv_replace_child(child, child_bs); + /* This performs the matching bdrv_set_perm() for the above check. */ + bdrv_replace_child(child, child_bs, false); return child; } @@ -XXX,XX +XXX,XX @@ static void bdrv_detach_child(BdrvChild *child) child->next.le_prev = NULL; } - bdrv_replace_child(child, NULL); + bdrv_replace_child(child, NULL, false); g_free(child->name); g_free(child); @@ -XXX,XX +XXX,XX @@ static void change_parent_backing_link(BlockDriverState *from, assert(c->role != &child_backing); bdrv_ref(to); - bdrv_replace_child(c, to); + /* FIXME Are we sure that bdrv_replace_child() can't run into + * &error_abort because of permissions? */ + bdrv_replace_child(c, to, true); bdrv_unref(from); } } 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 @@ struct BlockDriver { void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, Error **errp); + /** + * Informs the block driver that a permission change is intended. The + * driver checks whether the change is permissible and may take other + * preparations for the change (e.g. get file system locks). This operation + * is always followed either by a call to either .bdrv_set_perm or + * .bdrv_abort_perm_update. + * + * Checks whether the requested set of cumulative permissions in @perm + * can be granted for accessing @bs and whether no other users are using + * permissions other than those given in @shared (both arguments take + * BLK_PERM_* bitmasks). + * + * If both conditions are met, 0 is returned. Otherwise, -errno is returned + * and errp is set to an error describing the conflict. + */ + int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, + uint64_t shared, Error **errp); + + /** + * Called to inform the driver that the set of cumulative set of used + * permissions for @bs has changed to @perm, and the set of sharable + * permission to @shared. The driver can use this to propagate changes to + * its children (i.e. request permissions only if a parent actually needs + * them). + * + * This function is only invoked after bdrv_check_perm(), so block drivers + * may rely on preparations made in their .bdrv_check_perm implementation. + */ + void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); + + /* + * Called to inform the driver that after a previous bdrv_check_perm() + * call, the permission update is not performed and any preparations made + * for it (e.g. taken file locks) need to be undone. + * + * This function can be called even for nodes that never saw a + * bdrv_check_perm() call. It is a no-op then. + */ + void (*bdrv_abort_perm_update)(BlockDriverState *bs); + + /** + * Returns in @nperm and @nshared the permissions that the driver for @bs + * needs on its child @c, based on the cumulative permissions requested by + * the parents in @parent_perm and @parent_shared. + * + * If @c is NULL, return the permissions for attaching a new child for the + * given @role. + */ + void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t parent_perm, uint64_t parent_shared, + uint64_t *nperm, uint64_t *nshared); + QLIST_ENTRY(BlockDriver) list; }; @@ -XXX,XX +XXX,XX @@ BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, void *opaque, Error **errp); void bdrv_root_unref_child(BdrvChild *child); +int bdrv_child_check_perm(BdrvChild *c, uint64_t perm, uint64_t shared, + Error **errp); +void bdrv_child_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared); +void bdrv_child_abort_perm_update(BdrvChild *c); +int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, + Error **errp); + + const char *bdrv_get_parent_name(const BlockDriverState *bs); void blk_dev_change_media_cb(BlockBackend *blk, bool load); bool blk_dev_has_removable_media(BlockBackend *blk); -- 1.8.3.1 Most filters need permissions related to read and write for their children, but only if the node has a parent that wants to use the same operation on the filter. The same is true for resize. This adds a default implementation that simply forwards all necessary permissions to all children of the node and leaves the other permissions unchanged. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 23 +++++++++++++++++++++++ include/block/block_int.h | 8 ++++++++ 2 files changed, 31 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_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, return 0; } +#define DEFAULT_PERM_PASSTHROUGH (BLK_PERM_CONSISTENT_READ \ + | BLK_PERM_WRITE \ + | BLK_PERM_WRITE_UNCHANGED \ + | BLK_PERM_RESIZE) +#define DEFAULT_PERM_UNCHANGED (BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH) + +void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + if (c == NULL) { + *nperm = perm & DEFAULT_PERM_PASSTHROUGH; + *nshared = (shared & DEFAULT_PERM_PASSTHROUGH) | DEFAULT_PERM_UNCHANGED; + return; + } + + *nperm = (perm & DEFAULT_PERM_PASSTHROUGH) | + (c->perm & DEFAULT_PERM_UNCHANGED); + *nshared = (shared & DEFAULT_PERM_PASSTHROUGH) | + (c->shared_perm & DEFAULT_PERM_UNCHANGED); +} + static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, bool check_new_perm) { 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 @@ void bdrv_child_abort_perm_update(BdrvChild *c); int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, Error **errp); +/* Default implementation for BlockDriver.bdrv_child_perm() that can be used by + * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to + * all children */ +void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared); + const char *bdrv_get_parent_name(const BlockDriverState *bs); void blk_dev_change_media_cb(BlockBackend *blk, bool load); -- 1.8.3.1 All callers will have to request permissions for all of their child nodes. Block drivers that act as simply filters can use the default implementation of .bdrv_child_perm(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/blkdebug.c | 2 ++ block/blkreplay.c | 1 + block/blkverify.c | 1 + block/quorum.c | 2 ++ block/raw-format.c | 1 + block/replication.c | 1 + 6 files changed, 8 insertions(+) diff --git a/block/blkdebug.c b/block/blkdebug.c index XXXXXXX..XXXXXXX 100644 --- a/block/blkdebug.c +++ b/block/blkdebug.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_blkdebug = { .bdrv_file_open = blkdebug_open, .bdrv_close = blkdebug_close, .bdrv_reopen_prepare = blkdebug_reopen_prepare, + .bdrv_child_perm = bdrv_filter_default_perms, + .bdrv_getlength = blkdebug_getlength, .bdrv_truncate = blkdebug_truncate, .bdrv_refresh_filename = blkdebug_refresh_filename, diff --git a/block/blkreplay.c b/block/blkreplay.c index XXXXXXX..XXXXXXX 100755 --- a/block/blkreplay.c +++ b/block/blkreplay.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_blkreplay = { .bdrv_file_open = blkreplay_open, .bdrv_close = blkreplay_close, + .bdrv_child_perm = bdrv_filter_default_perms, .bdrv_getlength = blkreplay_getlength, .bdrv_co_preadv = blkreplay_co_preadv, diff --git a/block/blkverify.c b/block/blkverify.c index XXXXXXX..XXXXXXX 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_blkverify = { .bdrv_parse_filename = blkverify_parse_filename, .bdrv_file_open = blkverify_open, .bdrv_close = blkverify_close, + .bdrv_child_perm = bdrv_filter_default_perms, .bdrv_getlength = blkverify_getlength, .bdrv_refresh_filename = blkverify_refresh_filename, 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 BlockDriver bdrv_quorum = { .bdrv_add_child = quorum_add_child, .bdrv_del_child = quorum_del_child, + .bdrv_child_perm = bdrv_filter_default_perms, + .is_filter = true, .bdrv_recurse_is_first_non_filter = quorum_recurse_is_first_non_filter, }; 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 @@ BlockDriver bdrv_raw = { .bdrv_reopen_abort = &raw_reopen_abort, .bdrv_open = &raw_open, .bdrv_close = &raw_close, + .bdrv_child_perm = bdrv_filter_default_perms, .bdrv_create = &raw_create, .bdrv_co_preadv = &raw_co_preadv, .bdrv_co_pwritev = &raw_co_pwritev, 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 @@ BlockDriver bdrv_replication = { .bdrv_open = replication_open, .bdrv_close = replication_close, + .bdrv_child_perm = bdrv_filter_default_perms, .bdrv_getlength = replication_getlength, .bdrv_co_readv = replication_co_readv, -- 1.8.3.1 Almost all format drivers have the same characteristics as far as permissions are concerned: They have one or more children for storing their own data and, more importantly, metadata (can be written to and grow even without external write requests, must be protected against other writers and present consistent data) and optionally a backing file (this is just data, so like for a filter, it only depends on what the parent nodes need). This provides a default implementation that can be shared by most of our format drivers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ include/block/block_int.h | 8 ++++++++ 2 files changed, 52 insertions(+) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, (c->shared_perm & DEFAULT_PERM_UNCHANGED); } +void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + bool backing = (role == &child_backing); + assert(role == &child_backing || role == &child_file); + + if (!backing) { + /* Apart from the modifications below, the same permissions are + * forwarded and left alone as for filters */ + bdrv_filter_default_perms(bs, c, role, perm, shared, &perm, &shared); + + /* Format drivers may touch metadata even if the guest doesn't write */ + if (!bdrv_is_read_only(bs)) { + perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE; + } + + /* bs->file always needs to be consistent because of the metadata. We + * can never allow other users to resize or write to it. */ + perm |= BLK_PERM_CONSISTENT_READ; + shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); + } else { + /* We want consistent read from backing files if the parent needs it. + * No other operations are performed on backing files. */ + perm &= BLK_PERM_CONSISTENT_READ; + + /* If the parent can deal with changing data, we're okay with a + * writable and resizable backing file. */ + /* TODO Require !(perm & BLK_PERM_CONSISTENT_READ), too? */ + if (shared & BLK_PERM_WRITE) { + shared = BLK_PERM_WRITE | BLK_PERM_RESIZE; + } else { + shared = 0; + } + + shared |= BLK_PERM_CONSISTENT_READ | BLK_PERM_GRAPH_MOD | + BLK_PERM_WRITE_UNCHANGED; + } + + *nperm = perm; + *nshared = shared; +} + static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, bool check_new_perm) { 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 @@ void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, uint64_t perm, uint64_t shared, uint64_t *nperm, uint64_t *nshared); +/* Default implementation for BlockDriver.bdrv_child_perm() that can be used by + * (non-raw) image formats: Like above for bs->backing, but for bs->file it + * requires WRITE | RESIZE for read-write images, always requires + * CONSISTENT_READ and doesn't share WRITE. */ +void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared); const char *bdrv_get_parent_name(const BlockDriverState *bs); void blk_dev_change_media_cb(BlockBackend *blk, bool load); -- 1.8.3.1 This makes use of the .bdrv_child_perm() implementation for formats that we just added. All format drivers expose the permissions they actually need nows, so that they can be set accordingly and updated when parents are attached or detached. The only format not included here is raw, which was already converted with the other filter drivers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/bochs.c | 1 + block/cloop.c | 1 + block/crypto.c | 1 + block/dmg.c | 1 + block/parallels.c | 1 + block/qcow.c | 1 + block/qcow2.c | 1 + block/qed.c | 1 + block/vdi.c | 1 + block/vhdx.c | 1 + block/vmdk.c | 1 + block/vpc.c | 1 + 12 files changed, 12 insertions(+) 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 BlockDriver bdrv_bochs = { .instance_size = sizeof(BDRVBochsState), .bdrv_probe = bochs_probe, .bdrv_open = bochs_open, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_refresh_limits = bochs_refresh_limits, .bdrv_co_preadv = bochs_co_preadv, .bdrv_close = bochs_close, 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 BlockDriver bdrv_cloop = { .instance_size = sizeof(BDRVCloopState), .bdrv_probe = cloop_probe, .bdrv_open = cloop_open, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_refresh_limits = cloop_refresh_limits, .bdrv_co_preadv = cloop_co_preadv, .bdrv_close = cloop_close, 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 @@ BlockDriver bdrv_crypto_luks = { .bdrv_probe = block_crypto_probe_luks, .bdrv_open = block_crypto_open_luks, .bdrv_close = block_crypto_close, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_create = block_crypto_create_luks, .bdrv_truncate = block_crypto_truncate, .create_opts = &block_crypto_create_opts_luks, 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 BlockDriver bdrv_dmg = { .bdrv_probe = dmg_probe, .bdrv_open = dmg_open, .bdrv_refresh_limits = dmg_refresh_limits, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_co_preadv = dmg_co_preadv, .bdrv_close = dmg_close, }; 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 BlockDriver bdrv_parallels = { .bdrv_probe = parallels_probe, .bdrv_open = parallels_open, .bdrv_close = parallels_close, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_co_get_block_status = parallels_co_get_block_status, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_flush_to_os = parallels_co_flush_to_os, 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 BlockDriver bdrv_qcow = { .bdrv_probe = qcow_probe, .bdrv_open = qcow_open, .bdrv_close = qcow_close, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_reopen_prepare = qcow_reopen_prepare, .bdrv_create = qcow_create, .bdrv_has_zero_init = bdrv_has_zero_init_1, 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 @@ BlockDriver bdrv_qcow2 = { .bdrv_reopen_commit = qcow2_reopen_commit, .bdrv_reopen_abort = qcow2_reopen_abort, .bdrv_join_options = qcow2_join_options, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_create = qcow2_create, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_get_block_status = qcow2_co_get_block_status, 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 BlockDriver bdrv_qed = { .bdrv_open = bdrv_qed_open, .bdrv_close = bdrv_qed_close, .bdrv_reopen_prepare = bdrv_qed_reopen_prepare, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_create = bdrv_qed_create, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_get_block_status = bdrv_qed_co_get_block_status, 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 BlockDriver bdrv_vdi = { .bdrv_open = vdi_open, .bdrv_close = vdi_close, .bdrv_reopen_prepare = vdi_reopen_prepare, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_create = vdi_create, .bdrv_has_zero_init = bdrv_has_zero_init_1, .bdrv_co_get_block_status = vdi_co_get_block_status, 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 BlockDriver bdrv_vhdx = { .bdrv_open = vhdx_open, .bdrv_close = vhdx_close, .bdrv_reopen_prepare = vhdx_reopen_prepare, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_co_readv = vhdx_co_readv, .bdrv_co_writev = vhdx_co_writev, .bdrv_create = vhdx_create, 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 BlockDriver bdrv_vmdk = { .bdrv_open = vmdk_open, .bdrv_check = vmdk_check, .bdrv_reopen_prepare = vmdk_reopen_prepare, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_co_preadv = vmdk_co_preadv, .bdrv_co_pwritev = vmdk_co_pwritev, .bdrv_co_pwritev_compressed = vmdk_co_pwritev_compressed, 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 BlockDriver bdrv_vpc = { .bdrv_open = vpc_open, .bdrv_close = vpc_close, .bdrv_reopen_prepare = vpc_reopen_prepare, + .bdrv_child_perm = bdrv_format_default_perms, .bdrv_create = vpc_create, .bdrv_co_preadv = vpc_co_preadv, -- 1.8.3.1 vvfat is the last remaining driver that can have children, but doesn't implement .bdrv_child_perm() yet. The default handlers aren't suitable here, so let's implement a very simple driver-specific one that protects the internal child from being used by other users as good as our permissions permit. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 2 +- block/vvfat.c | 22 ++++++++++++++++++++++ include/block/block_int.h | 1 + 3 files changed, 24 insertions(+), 1 deletion(-) 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_backing_options(int *child_flags, QDict *child_options, *child_flags = flags; } -static const BdrvChildRole child_backing = { +const BdrvChildRole child_backing = { .inherit_options = bdrv_backing_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, 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 @@ err: return ret; } +static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + BDRVVVFATState *s = bs->opaque; + + assert(c == s->qcow || role == &child_backing); + + if (c == s->qcow) { + /* This is a private node, nobody should try to attach to it */ + *nperm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE; + *nshared = BLK_PERM_WRITE_UNCHANGED; + } else { + /* The backing file is there so 'commit' can use it. vvfat doesn't + * access it in any way. */ + *nperm = 0; + *nshared = BLK_PERM_ALL; + } +} + static void vvfat_close(BlockDriverState *bs) { BDRVVVFATState *s = bs->opaque; @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_vvfat = { .bdrv_file_open = vvfat_open, .bdrv_refresh_limits = vvfat_refresh_limits, .bdrv_close = vvfat_close, + .bdrv_child_perm = vvfat_child_perm, .bdrv_co_preadv = vvfat_co_preadv, .bdrv_co_pwritev = vvfat_co_pwritev, 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 @@ struct BdrvChildRole { extern const BdrvChildRole child_file; extern const BdrvChildRole child_format; +extern const BdrvChildRole child_backing; struct BdrvChild { BlockDriverState *bs; -- 1.8.3.1 All block drivers that can have child nodes implement .bdrv_child_perm() now. Make this officially a requirement by asserting that only drivers without children can omit .bdrv_child_perm(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 6 ++++-- 1 file changed, 4 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 int bdrv_check_perm(BlockDriverState *bs, uint64_t cumulative_perms, cumulative_shared_perms, errp); } - /* Drivers may not have .bdrv_child_perm() */ + /* Drivers that never have children can omit .bdrv_child_perm() */ if (!drv->bdrv_child_perm) { + assert(QLIST_EMPTY(&bs->children)); return 0; } @@ -XXX,XX +XXX,XX @@ static void bdrv_set_perm(BlockDriverState *bs, uint64_t cumulative_perms, drv->bdrv_set_perm(bs, cumulative_perms, cumulative_shared_perms); } - /* Drivers may not have .bdrv_child_perm() */ + /* Drivers that never have children can omit .bdrv_child_perm() */ if (!drv->bdrv_child_perm) { + assert(QLIST_EMPTY(&bs->children)); return; } -- 1.8.3.1 Now that all block drivers with children tell us what permissions they need from each of their children, bdrv_attach_child() can use this information and make the right requirements while trying to attach new children. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 10 ++++++++-- 1 file changed, 8 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 @@ BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, Error **errp) { BdrvChild *child; + uint64_t perm, shared_perm; + + bdrv_get_cumulative_perm(parent_bs, &perm, &shared_perm); + + assert(parent_bs->drv); + parent_bs->drv->bdrv_child_perm(parent_bs, NULL, child_role, + perm, shared_perm, &perm, &shared_perm); - /* FIXME Use real permissions */ child = bdrv_root_attach_child(child_bs, child_name, child_role, - 0, BLK_PERM_ALL, parent_bs, errp); + perm, shared_perm, parent_bs, errp); if (child == NULL) { return NULL; } -- 1.8.3.1 The BlockBackend can now store the permissions that its user requires. This is necessary because nodes can be ejected from or inserted into a BlockBackend and all of these operations must make sure that the user still gets what it requested initially. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/block-backend.c | 27 +++++++++++++++++++++++++++ include/sysemu/block-backend.h | 2 ++ 2 files changed, 29 insertions(+) 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 @@ struct BlockBackend { bool iostatus_enabled; BlockDeviceIoStatus iostatus; + uint64_t perm; + uint64_t shared_perm; + bool allow_write_beyond_eof; NotifierList remove_bs_notifiers, insert_bs_notifiers; @@ -XXX,XX +XXX,XX @@ BlockBackend *blk_new(void) blk = g_new0(BlockBackend, 1); blk->refcnt = 1; + blk->perm = 0; + blk->shared_perm = BLK_PERM_ALL; blk_set_enable_write_cache(blk, true); qemu_co_queue_init(&blk->public.throttled_reqs[0]); @@ -XXX,XX +XXX,XX @@ void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) } } +/* + * Sets the permission bitmasks that the user of the BlockBackend needs. + */ +int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, + Error **errp) +{ + int ret; + + if (blk->root) { + ret = bdrv_child_try_set_perm(blk->root, perm, shared_perm, errp); + if (ret < 0) { + return ret; + } + } + + blk->perm = perm; + blk->shared_perm = shared_perm; + + return 0; +} + static int blk_do_attach_dev(BlockBackend *blk, void *dev) { if (blk->dev) { @@ -XXX,XX +XXX,XX @@ void blk_detach_dev(BlockBackend *blk, void *dev) blk->dev_ops = NULL; blk->dev_opaque = NULL; blk->guest_block_size = 512; + blk_set_perm(blk, 0, BLK_PERM_ALL, &error_abort); blk_unref(blk); } 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 @@ void blk_remove_bs(BlockBackend *blk); void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs); bool bdrv_has_blk(BlockDriverState *bs); bool bdrv_is_root_node(BlockDriverState *bs); +int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, + Error **errp); void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow); void blk_iostatus_enable(BlockBackend *blk); -- 1.8.3.1 We want every user to be specific about the permissions it needs, so we'll pass the initial permissions as parameters to blk_new(). A user only needs to call blk_set_perm() if it wants to change the permissions after the fact. The permissions are stored in the BlockBackend and applied whenever a BlockDriverState should be attached in blk_insert_bs(). This does not include actually choosing the right set of permissions everywhere yet. Instead, the usual FIXME comment is added to each place and will be addressed in individual patches. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 2 +- block/backup.c | 3 ++- block/block-backend.c | 21 ++++++++++++++------- block/commit.c | 12 ++++++++---- block/mirror.c | 3 ++- block/qcow2.c | 2 +- blockdev.c | 4 ++-- blockjob.c | 3 ++- hmp.c | 3 ++- hw/block/fdc.c | 3 ++- hw/core/qdev-properties-system.c | 3 ++- hw/ide/qdev.c | 3 ++- hw/scsi/scsi-disk.c | 3 ++- include/sysemu/block-backend.h | 2 +- migration/block.c | 3 ++- nbd/server.c | 3 ++- tests/test-blockjob.c | 3 ++- tests/test-throttle.c | 7 ++++--- 18 files changed, 53 insertions(+), 30 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static BlockDriverState *bdrv_open_inherit(const char *filename, goto fail; } if (file_bs != NULL) { - file = blk_new(); + file = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); blk_insert_bs(file, file_bs); bdrv_unref(file_bs); diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, goto error; } - job->target = blk_new(); + /* FIXME Use real permissions */ + job->target = blk_new(0, BLK_PERM_ALL); blk_insert_bs(job->target, target); job->on_source_error = on_source_error; 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 const BdrvChildRole child_root = { /* * Create a new BlockBackend with a reference count of one. - * Store an error through @errp on failure, unless it's null. + * + * @perm is a bitmasks of BLK_PERM_* constants which describes the permissions + * to request for a block driver node that is attached to this BlockBackend. + * @shared_perm is a bitmask which describes which permissions may be granted + * to other users of the attached node. + * Both sets of permissions can be changed later using blk_set_perm(). + * * Return the new BlockBackend on success, null on failure. */ -BlockBackend *blk_new(void) +BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm) { BlockBackend *blk; blk = g_new0(BlockBackend, 1); blk->refcnt = 1; - blk->perm = 0; - blk->shared_perm = BLK_PERM_ALL; + blk->perm = perm; + blk->shared_perm = shared_perm; blk_set_enable_write_cache(blk, true); qemu_co_queue_init(&blk->public.throttled_reqs[0]); @@ -XXX,XX +XXX,XX @@ BlockBackend *blk_new_open(const char *filename, const char *reference, BlockBackend *blk; BlockDriverState *bs; - blk = blk_new(); + blk = blk_new(0, BLK_PERM_ALL); bs = bdrv_open(filename, reference, options, flags, errp); if (!bs) { blk_unref(blk); @@ -XXX,XX +XXX,XX @@ void blk_remove_bs(BlockBackend *blk) void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) { bdrv_ref(bs); - /* FIXME Use real permissions */ + /* FIXME Error handling */ blk->root = bdrv_root_attach_child(bs, "root", &child_root, - 0, BLK_PERM_ALL, blk, &error_abort); + blk->perm, blk->shared_perm, blk, + &error_abort); notifier_list_notify(&blk->insert_bs_notifiers, blk); if (blk->public.throttle_state) { 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 @@ void commit_start(const char *job_id, BlockDriverState *bs, block_job_add_bdrv(&s->common, overlay_bs); } - s->base = blk_new(); + /* FIXME Use real permissions */ + s->base = blk_new(0, BLK_PERM_ALL); blk_insert_bs(s->base, base); - s->top = blk_new(); + /* FIXME Use real permissions */ + s->top = blk_new(0, BLK_PERM_ALL); blk_insert_bs(s->top, top); s->active = bs; @@ -XXX,XX +XXX,XX @@ int bdrv_commit(BlockDriverState *bs) } } - src = blk_new(); + /* FIXME Use real permissions */ + src = blk_new(0, BLK_PERM_ALL); blk_insert_bs(src, bs); - backing = blk_new(); + /* FIXME Use real permissions */ + backing = blk_new(0, BLK_PERM_ALL); blk_insert_bs(backing, bs->backing->bs); length = blk_getlength(src); diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, return; } - s->target = blk_new(); + /* FIXME Use real permissions */ + s->target = blk_new(0, BLK_PERM_ALL); blk_insert_bs(s->target, target); s->replaces = g_strdup(replaces); 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_amend_options(BlockDriverState *bs, QemuOpts *opts, } if (new_size) { - BlockBackend *blk = blk_new(); + BlockBackend *blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL); blk_insert_bs(blk, bs); ret = blk_truncate(blk, new_size); blk_unref(blk); 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, if ((!file || !*file) && !qdict_size(bs_opts)) { BlockBackendRootState *blk_rs; - blk = blk_new(); + blk = blk_new(0, BLK_PERM_ALL); blk_rs = blk_get_root_state(blk); blk_rs->open_flags = bdrv_flags; blk_rs->read_only = read_only; @@ -XXX,XX +XXX,XX @@ void qmp_block_resize(bool has_device, const char *device, goto out; } - blk = blk_new(); + blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL); blk_insert_bs(blk, bs); /* complete all in-flight operations before resizing the device */ diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, } } - blk = blk_new(); + /* FIXME Use real permissions */ + blk = blk_new(0, BLK_PERM_ALL); blk_insert_bs(blk, bs); job = g_malloc0(driver->instance_size); diff --git a/hmp.c b/hmp.c index XXXXXXX..XXXXXXX 100644 --- a/hmp.c +++ b/hmp.c @@ -XXX,XX +XXX,XX @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict) if (!blk) { BlockDriverState *bs = bdrv_lookup_bs(NULL, device, &err); if (bs) { - blk = local_blk = blk_new(); + /* FIXME Use real permissions */ + blk = local_blk = blk_new(0, BLK_PERM_ALL); blk_insert_bs(blk, bs); } else { goto fail; diff --git a/hw/block/fdc.c b/hw/block/fdc.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -XXX,XX +XXX,XX @@ static int floppy_drive_init(DeviceState *qdev) if (!dev->conf.blk) { /* Anonymous BlockBackend for an empty drive */ - dev->conf.blk = blk_new(); + /* FIXME Use real permissions */ + dev->conf.blk = blk_new(0, BLK_PERM_ALL); ret = blk_attach_dev(dev->conf.blk, qdev); assert(ret == 0); } diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c index XXXXXXX..XXXXXXX 100644 --- a/hw/core/qdev-properties-system.c +++ b/hw/core/qdev-properties-system.c @@ -XXX,XX +XXX,XX @@ static void parse_drive(DeviceState *dev, const char *str, void **ptr, if (!blk) { BlockDriverState *bs = bdrv_lookup_bs(NULL, str, NULL); if (bs) { - blk = blk_new(); + /* FIXME Use real permissions */ + blk = blk_new(0, BLK_PERM_ALL); blk_insert_bs(blk, bs); blk_created = true; } diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c index XXXXXXX..XXXXXXX 100644 --- a/hw/ide/qdev.c +++ b/hw/ide/qdev.c @@ -XXX,XX +XXX,XX @@ static int ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind) return -1; } else { /* Anonymous BlockBackend for an empty drive */ - dev->conf.blk = blk_new(); + /* FIXME Use real permissions */ + dev->conf.blk = blk_new(0, BLK_PERM_ALL); } } diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index XXXXXXX..XXXXXXX 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -XXX,XX +XXX,XX @@ static void scsi_cd_realize(SCSIDevice *dev, Error **errp) SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, dev); if (!dev->conf.blk) { - dev->conf.blk = blk_new(); + /* FIXME Use real permissions */ + dev->conf.blk = blk_new(0, BLK_PERM_ALL); } s->qdev.blocksize = 2048; 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 @@ typedef struct BlockBackendPublic { QLIST_ENTRY(BlockBackendPublic) round_robin; } BlockBackendPublic; -BlockBackend *blk_new(void); +BlockBackend *blk_new(uint64_t perm, uint64_t shared_perm); BlockBackend *blk_new_open(const char *filename, const char *reference, QDict *options, int flags, Error **errp); int blk_get_refcnt(BlockBackend *blk); diff --git a/migration/block.c b/migration/block.c index XXXXXXX..XXXXXXX 100644 --- a/migration/block.c +++ b/migration/block.c @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) } bmds = g_new0(BlkMigDevState, 1); - bmds->blk = blk_new(); + /* FIXME Use real permissions */ + bmds->blk = blk_new(0, BLK_PERM_ALL); bmds->blk_name = g_strdup(bdrv_get_device_name(bs)); bmds->bulk_completed = 0; bmds->total_sectors = sectors; 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 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size, BlockBackend *blk; NBDExport *exp = g_malloc0(sizeof(NBDExport)); - blk = blk_new(); + /* FIXME Use real permissions */ + blk = blk_new(0, BLK_PERM_ALL); blk_insert_bs(blk, bs); blk_set_enable_write_cache(blk, !writethrough); diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-blockjob.c +++ b/tests/test-blockjob.c @@ -XXX,XX +XXX,XX @@ static BlockJob *do_test_id(BlockBackend *blk, const char *id, * BlockDriverState inserted. */ static BlockBackend *create_blk(const char *name) { - BlockBackend *blk = blk_new(); + /* FIXME Use real permissions */ + BlockBackend *blk = blk_new(0, BLK_PERM_ALL); BlockDriverState *bs; bs = bdrv_open("null-co://", NULL, NULL, 0, &error_abort); diff --git a/tests/test-throttle.c b/tests/test-throttle.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-throttle.c +++ b/tests/test-throttle.c @@ -XXX,XX +XXX,XX @@ static void test_groups(void) BlockBackend *blk1, *blk2, *blk3; BlockBackendPublic *blkp1, *blkp2, *blkp3; - blk1 = blk_new(); - blk2 = blk_new(); - blk3 = blk_new(); + /* FIXME Use real permissions */ + blk1 = blk_new(0, BLK_PERM_ALL); + blk2 = blk_new(0, BLK_PERM_ALL); + blk3 = blk_new(0, BLK_PERM_ALL); blkp1 = blk_get_public(blk1); blkp2 = blk_get_public(blk2); -- 1.8.3.1 Now that blk_insert_bs() requests the BlockBackend permissions for the node it attaches to, it can fail. Instead of aborting, pass the errors to the callers. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 5 ++++- block/backup.c | 5 ++++- block/block-backend.c | 13 ++++++++----- block/commit.c | 38 ++++++++++++++++++++++++++++++-------- block/mirror.c | 15 ++++++++++++--- block/qcow2.c | 10 ++++++++-- blockdev.c | 11 +++++++++-- blockjob.c | 7 ++++++- hmp.c | 6 +++++- hw/core/qdev-properties-system.c | 7 ++++++- include/sysemu/block-backend.h | 2 +- migration/block.c | 2 +- nbd/server.c | 6 +++++- tests/test-blockjob.c | 2 +- 14 files changed, 100 insertions(+), 29 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static BlockDriverState *bdrv_open_inherit(const char *filename, } if (file_bs != NULL) { file = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); - blk_insert_bs(file, file_bs); + blk_insert_bs(file, file_bs, &local_err); bdrv_unref(file_bs); + if (local_err) { + goto fail; + } qdict_put(options, "file", qstring_from_str(bdrv_get_node_name(file_bs))); diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, /* FIXME Use real permissions */ job->target = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(job->target, target); + ret = blk_insert_bs(job->target, target, errp); + if (ret < 0) { + goto error; + } job->on_source_error = on_source_error; job->on_target_error = on_target_error; 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_remove_bs(BlockBackend *blk) /* * Associates a new BlockDriverState with @blk. */ -void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs) +int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp) { - bdrv_ref(bs); - /* FIXME Error handling */ blk->root = bdrv_root_attach_child(bs, "root", &child_root, - blk->perm, blk->shared_perm, blk, - &error_abort); + blk->perm, blk->shared_perm, blk, errp); + if (blk->root == NULL) { + return -EPERM; + } + bdrv_ref(bs); notifier_list_notify(&blk->insert_bs_notifiers, blk); if (blk->public.throttle_state) { throttle_timers_attach_aio_context( &blk->public.throttle_timers, bdrv_get_aio_context(bs)); } + + return 0; } /* 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 @@ void commit_start(const char *job_id, BlockDriverState *bs, BlockDriverState *iter; BlockDriverState *overlay_bs; Error *local_err = NULL; + int ret; assert(top != bs); if (top == base) { @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, bdrv_reopen_multiple(bdrv_get_aio_context(bs), reopen_queue, &local_err); if (local_err != NULL) { error_propagate(errp, local_err); - block_job_unref(&s->common); - return; + goto fail; } } @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, /* FIXME Use real permissions */ s->base = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(s->base, base); + ret = blk_insert_bs(s->base, base, errp); + if (ret < 0) { + goto fail; + } /* FIXME Use real permissions */ s->top = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(s->top, top); + ret = blk_insert_bs(s->top, top, errp); + if (ret < 0) { + goto fail; + } s->active = bs; @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, trace_commit_start(bs, base, top, s); block_job_start(&s->common); + return; + +fail: + if (s->base) { + blk_unref(s->base); + } + if (s->top) { + blk_unref(s->top); + } + block_job_unref(&s->common); } @@ -XXX,XX +XXX,XX @@ int bdrv_commit(BlockDriverState *bs) /* FIXME Use real permissions */ src = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(src, bs); - - /* FIXME Use real permissions */ backing = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(backing, bs->backing->bs); + + ret = blk_insert_bs(src, bs, NULL); + if (ret < 0) { + goto ro_cleanup; + } + + ret = blk_insert_bs(backing, bs->backing->bs, NULL); + if (ret < 0) { + goto ro_cleanup; + } length = blk_getlength(src); if (length < 0) { diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) bdrv_replace_in_backing_chain(to_replace, target_bs); bdrv_drained_end(target_bs); - /* We just changed the BDS the job BB refers to */ + /* We just changed the BDS the job BB refers to, so switch the BB back + * so the cleanup does the right thing. We don't need any permissions + * any more now. */ blk_remove_bs(job->blk); - blk_insert_bs(job->blk, src); + blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort); + blk_insert_bs(job->blk, src, &error_abort); } if (s->to_replace) { bdrv_op_unblock_all(s->to_replace, s->replace_blocker); @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, bool auto_complete) { MirrorBlockJob *s; + int ret; if (granularity == 0) { granularity = bdrv_get_default_bitmap_granularity(target); @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, /* FIXME Use real permissions */ s->target = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(s->target, target); + ret = blk_insert_bs(s->target, target, errp); + if (ret < 0) { + blk_unref(s->target); + block_job_unref(&s->common); + return; + } s->replaces = g_strdup(replaces); s->on_source_error = on_source_error; 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_amend_options(BlockDriverState *bs, QemuOpts *opts, uint64_t cluster_size = s->cluster_size; bool encrypt; int refcount_bits = s->refcount_bits; + Error *local_err = NULL; int ret; QemuOptDesc *desc = opts->list->desc; Qcow2AmendHelperCBInfo helper_cb_info; @@ -XXX,XX +XXX,XX @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, if (new_size) { BlockBackend *blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL); - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, &local_err); + if (ret < 0) { + error_report_err(local_err); + blk_unref(blk); + return ret; + } + ret = blk_truncate(blk, new_size); blk_unref(blk); - if (ret < 0) { return ret; } diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ static void qmp_blockdev_insert_anon_medium(BlockBackend *blk, BlockDriverState *bs, Error **errp) { bool has_device; + int ret; /* For BBs without a device, we can exchange the BDS tree at will */ has_device = blk_get_attached_dev(blk); @@ -XXX,XX +XXX,XX @@ static void qmp_blockdev_insert_anon_medium(BlockBackend *blk, return; } - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + return; + } if (!blk_dev_has_tray(blk)) { /* For tray-less devices, blockdev-close-tray is a no-op (or may not be @@ -XXX,XX +XXX,XX @@ void qmp_block_resize(bool has_device, const char *device, } blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL); - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + goto out; + } /* complete all in-flight operations before resizing the device */ bdrv_drain_all(); diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, { BlockBackend *blk; BlockJob *job; + int ret; if (bs->job) { error_setg(errp, QERR_DEVICE_IN_USE, bdrv_get_device_name(bs)); @@ -XXX,XX +XXX,XX @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, /* FIXME Use real permissions */ blk = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + blk_unref(blk); + return NULL; + } job = g_malloc0(driver->instance_size); error_setg(&job->blocker, "block device is in use by block job: %s", diff --git a/hmp.c b/hmp.c index XXXXXXX..XXXXXXX 100644 --- a/hmp.c +++ b/hmp.c @@ -XXX,XX +XXX,XX @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict) const char* device = qdict_get_str(qdict, "device"); const char* command = qdict_get_str(qdict, "command"); Error *err = NULL; + int ret; blk = blk_by_name(device); if (!blk) { @@ -XXX,XX +XXX,XX @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict) if (bs) { /* FIXME Use real permissions */ blk = local_blk = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, &err); + if (ret < 0) { + goto fail; + } } else { goto fail; } diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c index XXXXXXX..XXXXXXX 100644 --- a/hw/core/qdev-properties-system.c +++ b/hw/core/qdev-properties-system.c @@ -XXX,XX +XXX,XX @@ static void parse_drive(DeviceState *dev, const char *str, void **ptr, { BlockBackend *blk; bool blk_created = false; + int ret; blk = blk_by_name(str); if (!blk) { @@ -XXX,XX +XXX,XX @@ static void parse_drive(DeviceState *dev, const char *str, void **ptr, if (bs) { /* FIXME Use real permissions */ blk = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(blk, bs); blk_created = true; + + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + goto fail; + } } } if (!blk) { 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 @@ BlockBackend *blk_by_public(BlockBackendPublic *public); BlockDriverState *blk_bs(BlockBackend *blk); void blk_remove_bs(BlockBackend *blk); -void blk_insert_bs(BlockBackend *blk, BlockDriverState *bs); +int blk_insert_bs(BlockBackend *blk, BlockDriverState *bs, Error **errp); bool bdrv_has_blk(BlockDriverState *bs); bool bdrv_is_root_node(BlockDriverState *bs); int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, diff --git a/migration/block.c b/migration/block.c index XXXXXXX..XXXXXXX 100644 --- a/migration/block.c +++ b/migration/block.c @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) BlockDriverState *bs = bmds_bs[i].bs; if (bmds) { - blk_insert_bs(bmds->blk, bs); + blk_insert_bs(bmds->blk, bs, &error_abort); alloc_aio_bitmap(bmds); error_setg(&bmds->blocker, "block device is in use by migration"); 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 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size, { BlockBackend *blk; NBDExport *exp = g_malloc0(sizeof(NBDExport)); + int ret; /* FIXME Use real permissions */ blk = blk_new(0, BLK_PERM_ALL); - blk_insert_bs(blk, bs); + ret = blk_insert_bs(blk, bs, errp); + if (ret < 0) { + goto fail; + } blk_set_enable_write_cache(blk, !writethrough); exp->refcount = 1; diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-blockjob.c +++ b/tests/test-blockjob.c @@ -XXX,XX +XXX,XX @@ static BlockBackend *create_blk(const char *name) bs = bdrv_open("null-co://", NULL, NULL, 0, &error_abort); g_assert_nonnull(bs); - blk_insert_bs(blk, bs); + blk_insert_bs(blk, bs, &error_abort); bdrv_unref(bs); if (name) { -- 1.8.3.1 blk_new_open() is a convenience function that processes flags rather than QDict options as a simple way to just open an image file. In order to keep it convenient in the future, it must automatically request the necessary permissions. This can easily be inferred from the flags for read and write, but we need another flag that tells us whether to get the resize permission. We can't just always request it because that means that no block jobs can run on the resulting BlockBackend (which is something that e.g. qemu-img commit wants to do), but we also can't request it never because most of the .bdrv_create() implementations call blk_truncate(). The solution is to introduce another flag that is passed by all users that want to resize the image. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block/parallels.c | 3 ++- block/qcow.c | 3 ++- block/qcow2.c | 6 ++++-- block/qed.c | 3 ++- block/sheepdog.c | 2 +- block/vdi.c | 3 ++- block/vhdx.c | 3 ++- block/vmdk.c | 6 ++++-- block/vpc.c | 3 ++- include/block/block.h | 1 + qemu-img.c | 2 +- 11 files changed, 23 insertions(+), 12 deletions(-) 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 parallels_create(const char *filename, QemuOpts *opts, Error **errp) } file = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (file == NULL) { error_propagate(errp, local_err); return -EIO; 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_create(const char *filename, QemuOpts *opts, Error **errp) } qcow_blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (qcow_blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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_create2(const char *filename, int64_t total_size, } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); return -EIO; @@ -XXX,XX +XXX,XX @@ static int qcow2_create2(const char *filename, int64_t total_size, options = qdict_new(); qdict_put(options, "driver", qstring_from_str("qcow2")); blk = blk_new_open(filename, NULL, options, - BDRV_O_RDWR | BDRV_O_NO_FLUSH, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_NO_FLUSH, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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 qed_create(const char *filename, uint32_t cluster_size, } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); return -EIO; diff --git a/block/sheepdog.c b/block/sheepdog.c index XXXXXXX..XXXXXXX 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -XXX,XX +XXX,XX @@ static int sd_prealloc(const char *filename, Error **errp) int ret; blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, errp); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, errp); if (blk == NULL) { ret = -EIO; goto out_with_err_set; 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 vdi_create(const char *filename, QemuOpts *opts, Error **errp) } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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 vhdx_create(const char *filename, QemuOpts *opts, Error **errp) } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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 vmdk_create_extent(const char *filename, int64_t filesize, } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); ret = -EIO; @@ -XXX,XX +XXX,XX @@ static int vmdk_create(const char *filename, QemuOpts *opts, Error **errp) } new_blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (new_blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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_create(const char *filename, QemuOpts *opts, Error **errp) } blk = blk_new_open(filename, NULL, NULL, - BDRV_O_RDWR | BDRV_O_PROTOCOL, &local_err); + BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL, + &local_err); if (blk == NULL) { error_propagate(errp, local_err); ret = -EIO; 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 { } HDGeometry; #define BDRV_O_RDWR 0x0002 +#define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 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 img_resize(int argc, char **argv) qemu_opts_del(param); blk = img_open(image_opts, filename, fmt, - BDRV_O_RDWR, false, quiet); + BDRV_O_RDWR | BDRV_O_RESIZE, false, quiet); if (!blk) { ret = -1; goto out; -- 1.8.3.1 We can figure out the necessary permissions from the flags that the caller passed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/block-backend.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) 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 @@ BlockBackend *blk_new_open(const char *filename, const char *reference, { BlockBackend *blk; BlockDriverState *bs; + uint64_t perm; + + /* blk_new_open() is mainly used in .bdrv_create implementations and the + * tools where sharing isn't a concern because the BDS stays private, so we + * just request permission according to the flags. + * + * The exceptions are xen_disk and blockdev_init(); in these cases, the + * caller of blk_new_open() doesn't make use of the permissions, but they + * shouldn't hurt either. We can still share everything here because the + * guest devices will add their own blockers if they can't share. */ + perm = BLK_PERM_CONSISTENT_READ; + if (flags & BDRV_O_RDWR) { + perm |= BLK_PERM_WRITE; + } + if (flags & BDRV_O_RESIZE) { + perm |= BLK_PERM_RESIZE; + } - blk = blk_new(0, BLK_PERM_ALL); + blk = blk_new(perm, BLK_PERM_ALL); bs = bdrv_open(filename, reference, options, flags, errp); if (!bs) { blk_unref(blk); return NULL; } - /* FIXME Use real permissions */ blk->root = bdrv_root_attach_child(bs, "root", &child_root, - 0, BLK_PERM_ALL, blk, &error_abort); + perm, BLK_PERM_ALL, blk, &error_abort); return blk; } -- 1.8.3.1 Some devices allow a media change between read-only and read-write media. They need to adapt the permissions in their .change_media_cb() implementation, which can fail. So add an Error parameter to the function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/block-backend.c | 20 +++++++++++++++----- blockdev.c | 19 +++++++++++++++---- hw/block/fdc.c | 2 +- hw/ide/core.c | 2 +- hw/scsi/scsi-disk.c | 2 +- hw/sd/sd.c | 2 +- include/block/block_int.h | 2 +- include/sysemu/block-backend.h | 2 +- 8 files changed, 36 insertions(+), 15 deletions(-) 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_set_dev_ops(BlockBackend *blk, const BlockDevOps *ops, /* * Notify @blk's attached device model of media change. - * If @load is true, notify of media load. - * Else, notify of media eject. + * + * If @load is true, notify of media load. This action can fail, meaning that + * the medium cannot be loaded. @errp is set then. + * + * If @load is false, notify of media eject. This can never fail. + * * Also send DEVICE_TRAY_MOVED events as appropriate. */ -void blk_dev_change_media_cb(BlockBackend *blk, bool load) +void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp) { if (blk->dev_ops && blk->dev_ops->change_media_cb) { bool tray_was_open, tray_is_open; + Error *local_err = NULL; assert(!blk->legacy_dev); tray_was_open = blk_dev_is_tray_open(blk); - blk->dev_ops->change_media_cb(blk->dev_opaque, load); + blk->dev_ops->change_media_cb(blk->dev_opaque, load, &local_err); + if (local_err) { + assert(load == true); + error_propagate(errp, local_err); + return; + } tray_is_open = blk_dev_is_tray_open(blk); if (tray_was_open != tray_is_open) { @@ -XXX,XX +XXX,XX @@ void blk_dev_change_media_cb(BlockBackend *blk, bool load) static void blk_root_change_media(BdrvChild *child, bool load) { - blk_dev_change_media_cb(child->opaque, load); + blk_dev_change_media_cb(child->opaque, load, NULL); } /* diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ static int do_open_tray(const char *blk_name, const char *qdev_id, } if (!locked || force) { - blk_dev_change_media_cb(blk, false); + blk_dev_change_media_cb(blk, false, &error_abort); } if (locked && !force) { @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_close_tray(bool has_device, const char *device, Error **errp) { BlockBackend *blk; + Error *local_err = NULL; device = has_device ? device : NULL; id = has_id ? id : NULL; @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_close_tray(bool has_device, const char *device, return; } - blk_dev_change_media_cb(blk, true); + blk_dev_change_media_cb(blk, true, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } } void qmp_x_blockdev_remove_medium(bool has_device, const char *device, @@ -XXX,XX +XXX,XX @@ void qmp_x_blockdev_remove_medium(bool has_device, const char *device, * called at all); therefore, the medium needs to be ejected here. * Do it after blk_remove_bs() so blk_is_inserted(blk) returns the @load * value passed here (i.e. false). */ - blk_dev_change_media_cb(blk, false); + blk_dev_change_media_cb(blk, false, &error_abort); } out: @@ -XXX,XX +XXX,XX @@ out: static void qmp_blockdev_insert_anon_medium(BlockBackend *blk, BlockDriverState *bs, Error **errp) { + Error *local_err = NULL; bool has_device; int ret; @@ -XXX,XX +XXX,XX @@ static void qmp_blockdev_insert_anon_medium(BlockBackend *blk, * slot here. * Do it after blk_insert_bs() so blk_is_inserted(blk) returns the @load * value passed here (i.e. true). */ - blk_dev_change_media_cb(blk, true); + blk_dev_change_media_cb(blk, true, &local_err); + if (local_err) { + error_propagate(errp, local_err); + blk_remove_bs(blk); + return; + } } } diff --git a/hw/block/fdc.c b/hw/block/fdc.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -XXX,XX +XXX,XX @@ static void fd_revalidate(FDrive *drv) } } -static void fd_change_cb(void *opaque, bool load) +static void fd_change_cb(void *opaque, bool load, Error **errp) { FDrive *drive = opaque; diff --git a/hw/ide/core.c b/hw/ide/core.c index XXXXXXX..XXXXXXX 100644 --- a/hw/ide/core.c +++ b/hw/ide/core.c @@ -XXX,XX +XXX,XX @@ static void ide_cfata_metadata_write(IDEState *s) } /* called when the inserted state of the media has changed */ -static void ide_cd_change_cb(void *opaque, bool load) +static void ide_cd_change_cb(void *opaque, bool load, Error **errp) { IDEState *s = opaque; uint64_t nb_sectors; diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index XXXXXXX..XXXXXXX 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -XXX,XX +XXX,XX @@ static void scsi_disk_resize_cb(void *opaque) } } -static void scsi_cd_change_media_cb(void *opaque, bool load) +static void scsi_cd_change_media_cb(void *opaque, bool load, Error **errp) { SCSIDiskState *s = opaque; diff --git a/hw/sd/sd.c b/hw/sd/sd.c index XXXXXXX..XXXXXXX 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -XXX,XX +XXX,XX @@ static bool sd_get_readonly(SDState *sd) return sd->wp_switch; } -static void sd_cardchange(void *opaque, bool load) +static void sd_cardchange(void *opaque, bool load, Error **errp) { SDState *sd = opaque; DeviceState *dev = DEVICE(sd); 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 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, uint64_t *nperm, uint64_t *nshared); const char *bdrv_get_parent_name(const BlockDriverState *bs); -void blk_dev_change_media_cb(BlockBackend *blk, bool load); +void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); bool blk_dev_has_removable_media(BlockBackend *blk); bool blk_dev_has_tray(BlockBackend *blk); void blk_dev_eject_request(BlockBackend *blk, bool force); 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 @@ typedef struct BlockDevOps { * changes. Sure would be useful if it did. * Device models with removable media must implement this callback. */ - void (*change_media_cb)(void *opaque, bool load); + void (*change_media_cb)(void *opaque, bool load, Error **errp); /* * Runs when an eject request is issued from the monitor, the tray * is closed, and the medium is locked. -- 1.8.3.1 This makes all device emulations with a qdev drive property request permissions on their BlockBackend. The only thing we block at this point is resizing images for some devices that can't support it. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- hw/block/block.c | 22 +++++++++++++++++++++- hw/block/fdc.c | 25 +++++++++++++++++++++++-- hw/block/m25p80.c | 8 ++++++++ hw/block/nand.c | 7 +++++++ hw/block/nvme.c | 8 +++++++- hw/block/onenand.c | 7 +++++++ hw/block/pflash_cfi01.c | 18 ++++++++++++------ hw/block/pflash_cfi02.c | 19 +++++++++++++------ hw/block/virtio-blk.c | 8 +++++++- hw/core/qdev-properties-system.c | 1 - hw/ide/qdev.c | 8 ++++++-- hw/nvram/spapr_nvram.c | 8 ++++++++ hw/scsi/scsi-disk.c | 9 +++++++-- hw/sd/sd.c | 6 ++++++ hw/usb/dev-storage.c | 6 +++++- include/hw/block/block.h | 3 ++- tests/qemu-iotests/051.pc.out | 6 +++--- 17 files changed, 142 insertions(+), 27 deletions(-) diff --git a/hw/block/block.c b/hw/block/block.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/block.c +++ b/hw/block/block.c @@ -XXX,XX +XXX,XX @@ void blkconf_blocksizes(BlockConf *conf) } } -void blkconf_apply_backend_options(BlockConf *conf) +void blkconf_apply_backend_options(BlockConf *conf, bool readonly, + bool resizable, Error **errp) { BlockBackend *blk = conf->blk; BlockdevOnError rerror, werror; + uint64_t perm, shared_perm; bool wce; + int ret; + + perm = BLK_PERM_CONSISTENT_READ; + if (!readonly) { + perm |= BLK_PERM_WRITE; + } + + /* TODO Remove BLK_PERM_WRITE unless explicitly configured so */ + shared_perm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | + BLK_PERM_GRAPH_MOD | BLK_PERM_WRITE; + if (resizable) { + shared_perm |= BLK_PERM_RESIZE; + } + + ret = blk_set_perm(blk, perm, shared_perm, errp); + if (ret < 0) { + return; + } switch (conf->wce) { case ON_OFF_AUTO_ON: wce = true; break; diff --git a/hw/block/fdc.c b/hw/block/fdc.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -XXX,XX +XXX,XX @@ typedef enum FDiskFlags { struct FDrive { FDCtrl *fdctrl; BlockBackend *blk; + BlockConf *conf; /* Drive status */ FloppyDriveType drive; /* CMOS drive type */ uint8_t perpendicular; /* 2.88 MB access mode */ @@ -XXX,XX +XXX,XX @@ static void fd_revalidate(FDrive *drv) static void fd_change_cb(void *opaque, bool load, Error **errp) { FDrive *drive = opaque; + Error *local_err = NULL; + + if (!load) { + blk_set_perm(drive->blk, 0, BLK_PERM_ALL, &error_abort); + } else { + blkconf_apply_backend_options(drive->conf, + blk_is_read_only(drive->blk), false, + &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } + } drive->media_changed = 1; drive->media_validated = false; @@ -XXX,XX +XXX,XX @@ static int floppy_drive_init(DeviceState *qdev) FloppyDrive *dev = FLOPPY_DRIVE(qdev); FloppyBus *bus = FLOPPY_BUS(qdev->parent_bus); FDrive *drive; + Error *local_err = NULL; int ret; if (dev->unit == -1) { @@ -XXX,XX +XXX,XX @@ static int floppy_drive_init(DeviceState *qdev) if (!dev->conf.blk) { /* Anonymous BlockBackend for an empty drive */ - /* FIXME Use real permissions */ dev->conf.blk = blk_new(0, BLK_PERM_ALL); ret = blk_attach_dev(dev->conf.blk, qdev); assert(ret == 0); @@ -XXX,XX +XXX,XX @@ static int floppy_drive_init(DeviceState *qdev) * blkconf_apply_backend_options(). */ dev->conf.rerror = BLOCKDEV_ON_ERROR_AUTO; dev->conf.werror = BLOCKDEV_ON_ERROR_AUTO; - blkconf_apply_backend_options(&dev->conf); + + blkconf_apply_backend_options(&dev->conf, blk_is_read_only(dev->conf.blk), + false, &local_err); + if (local_err) { + error_report_err(local_err); + return -1; + } /* 'enospc' is the default for -drive, 'report' is what blk_new() gives us * for empty drives. */ @@ -XXX,XX +XXX,XX @@ static int floppy_drive_init(DeviceState *qdev) return -1; } + drive->conf = &dev->conf; drive->blk = dev->conf.blk; drive->fdctrl = bus->fdc; diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/m25p80.c +++ b/hw/block/m25p80.c @@ -XXX,XX +XXX,XX @@ static void m25p80_realize(SSISlave *ss, Error **errp) { Flash *s = M25P80(ss); M25P80Class *mc = M25P80_GET_CLASS(s); + int ret; s->pi = mc->pi; @@ -XXX,XX +XXX,XX @@ static void m25p80_realize(SSISlave *ss, Error **errp) s->dirty_page = -1; if (s->blk) { + uint64_t perm = BLK_PERM_CONSISTENT_READ | + (blk_is_read_only(s->blk) ? 0 : BLK_PERM_WRITE); + ret = blk_set_perm(s->blk, perm, BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } + DB_PRINT_L(0, "Binding to IF_MTD drive\n"); s->storage = blk_blockalign(s->blk, s->size); diff --git a/hw/block/nand.c b/hw/block/nand.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/nand.c +++ b/hw/block/nand.c @@ -XXX,XX +XXX,XX @@ static void nand_realize(DeviceState *dev, Error **errp) { int pagesize; NANDFlashState *s = NAND(dev); + int ret; + s->buswidth = nand_flash_ids[s->chip_id].width >> 3; s->size = nand_flash_ids[s->chip_id].size << 20; @@ -XXX,XX +XXX,XX @@ static void nand_realize(DeviceState *dev, Error **errp) error_setg(errp, "Can't use a read-only drive"); return; } + ret = blk_set_perm(s->blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE, + BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } if (blk_getlength(s->blk) >= (s->pages << s->page_shift) + (s->pages << s->oob_shift)) { pagesize = 0; diff --git a/hw/block/nvme.c b/hw/block/nvme.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/nvme.c +++ b/hw/block/nvme.c @@ -XXX,XX +XXX,XX @@ static int nvme_init(PCIDevice *pci_dev) int i; int64_t bs_size; uint8_t *pci_conf; + Error *local_err = NULL; if (!n->conf.blk) { return -1; @@ -XXX,XX +XXX,XX @@ static int nvme_init(PCIDevice *pci_dev) return -1; } blkconf_blocksizes(&n->conf); - blkconf_apply_backend_options(&n->conf); + blkconf_apply_backend_options(&n->conf, blk_is_read_only(n->conf.blk), + false, &local_err); + if (local_err) { + error_report_err(local_err); + return -1; + } pci_conf = pci_dev->config; pci_conf[PCI_INTERRUPT_PIN] = 1; diff --git a/hw/block/onenand.c b/hw/block/onenand.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/onenand.c +++ b/hw/block/onenand.c @@ -XXX,XX +XXX,XX @@ static int onenand_initfn(SysBusDevice *sbd) OneNANDState *s = ONE_NAND(dev); uint32_t size = 1 << (24 + ((s->id.dev >> 4) & 7)); void *ram; + Error *local_err = NULL; s->base = (hwaddr)-1; s->rdy = NULL; @@ -XXX,XX +XXX,XX @@ static int onenand_initfn(SysBusDevice *sbd) error_report("Can't use a read-only drive"); return -1; } + blk_set_perm(s->blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE, + BLK_PERM_ALL, &local_err); + if (local_err) { + error_report_err(local_err); + return -1; + } s->blk_cur = s->blk; } s->otp = memset(g_malloc((64 + 2) << PAGE_SHIFT), diff --git a/hw/block/pflash_cfi01.c b/hw/block/pflash_cfi01.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/pflash_cfi01.c +++ b/hw/block/pflash_cfi01.c @@ -XXX,XX +XXX,XX @@ static void pflash_cfi01_realize(DeviceState *dev, Error **errp) sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem); if (pfl->blk) { + uint64_t perm; + pfl->ro = blk_is_read_only(pfl->blk); + perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE); + ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } + } else { + pfl->ro = 0; + } + + if (pfl->blk) { /* read the initial flash content */ ret = blk_pread(pfl->blk, 0, pfl->storage, total_len); @@ -XXX,XX +XXX,XX @@ static void pflash_cfi01_realize(DeviceState *dev, Error **errp) } } - if (pfl->blk) { - pfl->ro = blk_is_read_only(pfl->blk); - } else { - pfl->ro = 0; - } - /* Default to devices being used at their maximum device width. This was * assumed before the device_width support was added. */ diff --git a/hw/block/pflash_cfi02.c b/hw/block/pflash_cfi02.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/pflash_cfi02.c +++ b/hw/block/pflash_cfi02.c @@ -XXX,XX +XXX,XX @@ static void pflash_cfi02_realize(DeviceState *dev, Error **errp) vmstate_register_ram(&pfl->orig_mem, DEVICE(pfl)); pfl->storage = memory_region_get_ram_ptr(&pfl->orig_mem); pfl->chip_len = chip_len; + + if (pfl->blk) { + uint64_t perm; + pfl->ro = blk_is_read_only(pfl->blk); + perm = BLK_PERM_CONSISTENT_READ | (pfl->ro ? 0 : BLK_PERM_WRITE); + ret = blk_set_perm(pfl->blk, perm, BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } + } else { + pfl->ro = 0; + } + if (pfl->blk) { /* read the initial flash content */ ret = blk_pread(pfl->blk, 0, pfl->storage, chip_len); @@ -XXX,XX +XXX,XX @@ static void pflash_cfi02_realize(DeviceState *dev, Error **errp) pfl->rom_mode = 1; sysbus_init_mmio(SYS_BUS_DEVICE(dev), &pfl->mem); - if (pfl->blk) { - pfl->ro = blk_is_read_only(pfl->blk); - } else { - pfl->ro = 0; - } - pfl->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, pflash_timer, pfl); pfl->wcycle = 0; pfl->cmd = 0; diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/virtio-blk.c +++ b/hw/block/virtio-blk.c @@ -XXX,XX +XXX,XX @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp) } blkconf_serial(&conf->conf, &conf->serial); - blkconf_apply_backend_options(&conf->conf); + blkconf_apply_backend_options(&conf->conf, + blk_is_read_only(conf->conf.blk), true, + &err); + if (err) { + error_propagate(errp, err); + return; + } s->original_wce = blk_enable_write_cache(conf->conf.blk); blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, &err); if (err) { diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c index XXXXXXX..XXXXXXX 100644 --- a/hw/core/qdev-properties-system.c +++ b/hw/core/qdev-properties-system.c @@ -XXX,XX +XXX,XX @@ static void parse_drive(DeviceState *dev, const char *str, void **ptr, if (!blk) { BlockDriverState *bs = bdrv_lookup_bs(NULL, str, NULL); if (bs) { - /* FIXME Use real permissions */ blk = blk_new(0, BLK_PERM_ALL); blk_created = true; diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c index XXXXXXX..XXXXXXX 100644 --- a/hw/ide/qdev.c +++ b/hw/ide/qdev.c @@ -XXX,XX +XXX,XX @@ static int ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind) return -1; } else { /* Anonymous BlockBackend for an empty drive */ - /* FIXME Use real permissions */ dev->conf.blk = blk_new(0, BLK_PERM_ALL); } } @@ -XXX,XX +XXX,XX @@ static int ide_dev_initfn(IDEDevice *dev, IDEDriveKind kind) return -1; } } - blkconf_apply_backend_options(&dev->conf); + blkconf_apply_backend_options(&dev->conf, kind == IDE_CD, kind != IDE_CD, + &err); + if (err) { + error_report_err(err); + return -1; + } if (ide_init_drive(s, dev->conf.blk, kind, dev->version, dev->serial, dev->model, dev->wwn, diff --git a/hw/nvram/spapr_nvram.c b/hw/nvram/spapr_nvram.c index XXXXXXX..XXXXXXX 100644 --- a/hw/nvram/spapr_nvram.c +++ b/hw/nvram/spapr_nvram.c @@ -XXX,XX +XXX,XX @@ static void rtas_nvram_store(PowerPCCPU *cpu, sPAPRMachineState *spapr, static void spapr_nvram_realize(VIOsPAPRDevice *dev, Error **errp) { sPAPRNVRAM *nvram = VIO_SPAPR_NVRAM(dev); + int ret; if (nvram->blk) { nvram->size = blk_getlength(nvram->blk); + + ret = blk_set_perm(nvram->blk, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE, + BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } } else { nvram->size = DEFAULT_NVRAM_SIZE; } diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index XXXXXXX..XXXXXXX 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -XXX,XX +XXX,XX @@ static void scsi_realize(SCSIDevice *dev, Error **errp) return; } } - blkconf_apply_backend_options(&dev->conf); + blkconf_apply_backend_options(&dev->conf, + blk_is_read_only(s->qdev.conf.blk), + dev->type == TYPE_DISK, &err); + if (err) { + error_propagate(errp, err); + return; + } if (s->qdev.conf.discard_granularity == -1) { s->qdev.conf.discard_granularity = @@ -XXX,XX +XXX,XX @@ static void scsi_cd_realize(SCSIDevice *dev, Error **errp) SCSIDiskState *s = DO_UPCAST(SCSIDiskState, qdev, dev); if (!dev->conf.blk) { - /* FIXME Use real permissions */ dev->conf.blk = blk_new(0, BLK_PERM_ALL); } diff --git a/hw/sd/sd.c b/hw/sd/sd.c index XXXXXXX..XXXXXXX 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -XXX,XX +XXX,XX @@ static void sd_instance_finalize(Object *obj) static void sd_realize(DeviceState *dev, Error **errp) { SDState *sd = SD_CARD(dev); + int ret; if (sd->blk && blk_is_read_only(sd->blk)) { error_setg(errp, "Cannot use read-only drive as SD card"); @@ -XXX,XX +XXX,XX @@ static void sd_realize(DeviceState *dev, Error **errp) } if (sd->blk) { + ret = blk_set_perm(sd->blk, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE, + BLK_PERM_ALL, errp); + if (ret < 0) { + return; + } blk_set_dev_ops(sd->blk, &sd_block_ops, sd); } } diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c index XXXXXXX..XXXXXXX 100644 --- a/hw/usb/dev-storage.c +++ b/hw/usb/dev-storage.c @@ -XXX,XX +XXX,XX @@ static void usb_msd_realize_storage(USBDevice *dev, Error **errp) blkconf_serial(&s->conf, &dev->serial); blkconf_blocksizes(&s->conf); - blkconf_apply_backend_options(&s->conf); + blkconf_apply_backend_options(&s->conf, blk_is_read_only(blk), true, &err); + if (err) { + error_propagate(errp, err); + return; + } /* * Hack alert: this pretends to be a block device, but it's really diff --git a/include/hw/block/block.h b/include/hw/block/block.h index XXXXXXX..XXXXXXX 100644 --- a/include/hw/block/block.h +++ b/include/hw/block/block.h @@ -XXX,XX +XXX,XX @@ void blkconf_geometry(BlockConf *conf, int *trans, unsigned cyls_max, unsigned heads_max, unsigned secs_max, Error **errp); void blkconf_blocksizes(BlockConf *conf); -void blkconf_apply_backend_options(BlockConf *conf); +void blkconf_apply_backend_options(BlockConf *conf, bool readonly, + bool resizable, Error **errp); /* Hard disk geometry */ diff --git a/tests/qemu-iotests/051.pc.out b/tests/qemu-iotests/051.pc.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/051.pc.out +++ b/tests/qemu-iotests/051.pc.out @@ -XXX,XX +XXX,XX @@ qququiquit Testing: -drive file=TEST_DIR/t.qcow2,if=ide,readonly=on QEMU X.Y.Z monitor - type 'help' for more information -(qemu) QEMU_PROG: Can't use a read-only drive +(qemu) QEMU_PROG: Block node is read-only QEMU_PROG: Initialization of device ide-hd failed: Device initialization failed. Testing: -drive file=TEST_DIR/t.qcow2,if=scsi,readonly=on @@ -XXX,XX +XXX,XX @@ QEMU X.Y.Z monitor - type 'help' for more information Testing: -drive file=TEST_DIR/t.qcow2,if=none,id=disk,readonly=on -device ide-drive,drive=disk QEMU X.Y.Z monitor - type 'help' for more information -(qemu) QEMU_PROG: -device ide-drive,drive=disk: Can't use a read-only drive +(qemu) QEMU_PROG: -device ide-drive,drive=disk: Block node is read-only QEMU_PROG: -device ide-drive,drive=disk: Device initialization failed. Testing: -drive file=TEST_DIR/t.qcow2,if=none,id=disk,readonly=on -device ide-hd,drive=disk QEMU X.Y.Z monitor - type 'help' for more information -(qemu) QEMU_PROG: -device ide-hd,drive=disk: Can't use a read-only drive +(qemu) QEMU_PROG: -device ide-hd,drive=disk: Block node is read-only QEMU_PROG: -device ide-hd,drive=disk: Device initialization failed. Testing: -drive file=TEST_DIR/t.qcow2,if=none,id=disk,readonly=on -device lsi53c895a -device scsi-disk,drive=disk -- 1.8.3.1 By default, don't allow another writer for block devices that are attached to a guest device. For the cases where this setup is intended (e.g. using a cluster filesystem on the disk), the new option can be used to allow it. This change affects only devices using DEFINE_BLOCK_PROPERTIES(). Devices directly using DEFINE_PROP_DRIVE() still accept writers unconditionally. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- hw/block/block.c | 6 ++++-- include/hw/block/block.h | 5 ++++- tests/qemu-iotests/172.out | 53 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 61 insertions(+), 3 deletions(-) diff --git a/hw/block/block.c b/hw/block/block.c index XXXXXXX..XXXXXXX 100644 --- a/hw/block/block.c +++ b/hw/block/block.c @@ -XXX,XX +XXX,XX @@ void blkconf_apply_backend_options(BlockConf *conf, bool readonly, perm |= BLK_PERM_WRITE; } - /* TODO Remove BLK_PERM_WRITE unless explicitly configured so */ shared_perm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | - BLK_PERM_GRAPH_MOD | BLK_PERM_WRITE; + BLK_PERM_GRAPH_MOD; if (resizable) { shared_perm |= BLK_PERM_RESIZE; } + if (conf->share_rw) { + shared_perm |= BLK_PERM_WRITE; + } ret = blk_set_perm(blk, perm, shared_perm, errp); if (ret < 0) { diff --git a/include/hw/block/block.h b/include/hw/block/block.h index XXXXXXX..XXXXXXX 100644 --- a/include/hw/block/block.h +++ b/include/hw/block/block.h @@ -XXX,XX +XXX,XX @@ typedef struct BlockConf { /* geometry, not all devices use this */ uint32_t cyls, heads, secs; OnOffAuto wce; + bool share_rw; BlockdevOnError rerror; BlockdevOnError werror; } BlockConf; @@ -XXX,XX +XXX,XX @@ static inline unsigned int get_physical_block_exp(BlockConf *conf) DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0), \ DEFINE_PROP_UINT32("discard_granularity", _state, \ _conf.discard_granularity, -1), \ - DEFINE_PROP_ON_OFF_AUTO("write-cache", _state, _conf.wce, ON_OFF_AUTO_AUTO) + DEFINE_PROP_ON_OFF_AUTO("write-cache", _state, _conf.wce, \ + ON_OFF_AUTO_AUTO), \ + DEFINE_PROP_BOOL("share-rw", _state, _conf.share_rw, false) #define DEFINE_BLOCK_CHS_PROPERTIES(_state, _conf) \ DEFINE_PROP_UINT32("cyls", _state, _conf.cyls, 0), \ diff --git a/tests/qemu-iotests/172.out b/tests/qemu-iotests/172.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/172.out +++ b/tests/qemu-iotests/172.out @@ -XXX,XX +XXX,XX @@ Testing: opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fdb TEST_DIR/t.qcow2 @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" Testing: -fda TEST_DIR/t.qcow2 -fdb TEST_DIR/t.qcow2 @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -fdb TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -fdb TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=floppy,file=TEST_DIR/t.qcow2,index=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2,index=1 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2,index=1 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=floppy,file=TEST_DIR/t.qcow2,index=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=floppy,file=TEST_DIR/t opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=floppy,file=TEST_DIR/t opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveB=none0 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveB=none0 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 -global isa-fdc.driveB=none1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=1 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0 -device floppy,drive=none1,unit=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveB=none0 @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa- opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=1 @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0 @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 1 (0x1) @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=0 @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 1 (0x1) @@ -XXX,XX +XXX,XX @@ Testing: -fdb TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device flop opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -fda TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=0 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.q opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.q opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.q opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.q opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=floppy,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,unit=0 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 -device floppy,drive=none1,unit=1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 0 (0x0) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveB=none0 -device floppy,drive=none1 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 1 (0x1) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveB=none0 -device floppy,drive=none1,unit=0 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" dev: floppy, id "" unit = 1 (0x1) @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qco opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -drive if=none,file=TEST_DIR/t.qcow2 -global isa-fdc.driveA=none0 -device floppy,drive=none1,unit=0 @@ -XXX,XX +XXX,XX @@ Testing: -device floppy opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" Testing: -device floppy,drive-type=120 @@ -XXX,XX +XXX,XX @@ Testing: -device floppy,drive-type=120 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "120" Testing: -device floppy,drive-type=144 @@ -XXX,XX +XXX,XX @@ Testing: -device floppy,drive-type=144 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -device floppy,drive-type=288 @@ -XXX,XX +XXX,XX @@ Testing: -device floppy,drive-type=288 opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,drive-t opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "120" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,drive-type=288 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,drive-t opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "288" @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,logical opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,physical_block_size=512 @@ -XXX,XX +XXX,XX @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,physica opt_io_size = 0 (0x0) discard_granularity = 4294967295 (0xffffffff) write-cache = "auto" + share-rw = false drive-type = "144" Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device floppy,drive=none0,logical_block_size=4096 -- 1.8.3.1 This functions creates a BlockBackend internally, so the block jobs need to tell it what they want to do with the BB. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/backup.c | 5 +++-- block/commit.c | 5 +++-- block/mirror.c | 5 +++-- block/stream.c | 5 +++-- blockjob.c | 6 +++--- include/block/blockjob_int.h | 4 +++- tests/test-blockjob-txn.c | 6 +++--- tests/test-blockjob.c | 5 +++-- 8 files changed, 24 insertions(+), 17 deletions(-) diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, goto error; } - job = block_job_create(job_id, &backup_job_driver, bs, speed, - creation_flags, cb, opaque, errp); + /* FIXME Use real permissions */ + job = block_job_create(job_id, &backup_job_driver, bs, 0, BLK_PERM_ALL, + speed, creation_flags, cb, opaque, errp); if (!job) { goto error; } 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 @@ void commit_start(const char *job_id, BlockDriverState *bs, return; } - s = block_job_create(job_id, &commit_job_driver, bs, speed, - BLOCK_JOB_DEFAULT, NULL, NULL, errp); + /* FIXME Use real permissions */ + s = block_job_create(job_id, &commit_job_driver, bs, 0, BLK_PERM_ALL, + speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp); if (!s) { return; } diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, buf_size = DEFAULT_MIRROR_BUF_SIZE; } - s = block_job_create(job_id, driver, bs, speed, creation_flags, - cb, opaque, errp); + /* FIXME Use real permissions */ + s = block_job_create(job_id, driver, bs, 0, BLK_PERM_ALL, speed, + creation_flags, cb, opaque, errp); if (!s) { return; } 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 @@ void stream_start(const char *job_id, BlockDriverState *bs, BlockDriverState *iter; int orig_bs_flags; - s = block_job_create(job_id, &stream_job_driver, bs, speed, - BLOCK_JOB_DEFAULT, NULL, NULL, errp); + /* FIXME Use real permissions */ + s = block_job_create(job_id, &stream_job_driver, bs, 0, BLK_PERM_ALL, + speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp); if (!s) { return; } diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ void block_job_add_bdrv(BlockJob *job, BlockDriverState *bs) } void *block_job_create(const char *job_id, const BlockJobDriver *driver, - BlockDriverState *bs, int64_t speed, int flags, + BlockDriverState *bs, uint64_t perm, + uint64_t shared_perm, int64_t speed, int flags, BlockCompletionFunc *cb, void *opaque, Error **errp) { BlockBackend *blk; @@ -XXX,XX +XXX,XX @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, } } - /* FIXME Use real permissions */ - blk = blk_new(0, BLK_PERM_ALL); + blk = blk_new(perm, shared_perm); ret = blk_insert_bs(blk, bs, errp); if (ret < 0) { blk_unref(blk); diff --git a/include/block/blockjob_int.h b/include/block/blockjob_int.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/blockjob_int.h +++ b/include/block/blockjob_int.h @@ -XXX,XX +XXX,XX @@ struct BlockJobDriver { * generated automatically. * @job_type: The class object for the newly-created job. * @bs: The block + * @perm, @shared_perm: Permissions to request for @bs * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @cb: Completion function for the job. * @opaque: Opaque pointer value passed to @cb. @@ -XXX,XX +XXX,XX @@ struct BlockJobDriver { * called from a wrapper that is specific to the job type. */ void *block_job_create(const char *job_id, const BlockJobDriver *driver, - BlockDriverState *bs, int64_t speed, int flags, + BlockDriverState *bs, uint64_t perm, + uint64_t shared_perm, int64_t speed, int flags, BlockCompletionFunc *cb, void *opaque, Error **errp); /** diff --git a/tests/test-blockjob-txn.c b/tests/test-blockjob-txn.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-blockjob-txn.c +++ b/tests/test-blockjob-txn.c @@ -XXX,XX +XXX,XX @@ static BlockJob *test_block_job_start(unsigned int iterations, g_assert_nonnull(bs); snprintf(job_id, sizeof(job_id), "job%u", counter++); - s = block_job_create(job_id, &test_block_job_driver, bs, 0, - BLOCK_JOB_DEFAULT, test_block_job_cb, - data, &error_abort); + s = block_job_create(job_id, &test_block_job_driver, bs, + 0, BLK_PERM_ALL, 0, BLOCK_JOB_DEFAULT, + test_block_job_cb, data, &error_abort); s->iterations = iterations; s->use_timer = use_timer; s->rc = rc; diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-blockjob.c +++ b/tests/test-blockjob.c @@ -XXX,XX +XXX,XX @@ static BlockJob *do_test_id(BlockBackend *blk, const char *id, BlockJob *job; Error *errp = NULL; - job = block_job_create(id, &test_block_job_driver, blk_bs(blk), 0, - BLOCK_JOB_DEFAULT, block_job_cb, NULL, &errp); + job = block_job_create(id, &test_block_job_driver, blk_bs(blk), + 0, BLK_PERM_ALL, 0, BLOCK_JOB_DEFAULT, block_job_cb, + NULL, &errp); if (should_succeed) { g_assert_null(errp); g_assert_nonnull(job); -- 1.8.3.1 For meaningful error messages in the permission system, we need to get some human-readable description of the parent of a BdrvChild. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 9 +++++++++ block/block-backend.c | 21 +++++++++++++++++++++ include/block/block_int.h | 6 ++++++ 3 files changed, 36 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_parse_cache_mode(const char *mode, int *flags, bool *writethrough) return 0; } +static char *bdrv_child_get_parent_desc(BdrvChild *c) +{ + BlockDriverState *parent = c->opaque; + return g_strdup(bdrv_get_device_or_node_name(parent)); +} + static void bdrv_child_cb_drained_begin(BdrvChild *child) { BlockDriverState *bs = child->opaque; @@ -XXX,XX +XXX,XX @@ static void bdrv_inherited_options(int *child_flags, QDict *child_options, } const BdrvChildRole child_file = { + .get_parent_desc = bdrv_child_get_parent_desc, .inherit_options = bdrv_inherited_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, @@ -XXX,XX +XXX,XX @@ static void bdrv_inherited_fmt_options(int *child_flags, QDict *child_options, } const BdrvChildRole child_format = { + .get_parent_desc = bdrv_child_get_parent_desc, .inherit_options = bdrv_inherited_fmt_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, @@ -XXX,XX +XXX,XX @@ static void bdrv_backing_options(int *child_flags, QDict *child_options, } const BdrvChildRole child_backing = { + .get_parent_desc = bdrv_child_get_parent_desc, .inherit_options = bdrv_backing_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, 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 const AIOCBInfo block_backend_aiocb_info = { static void drive_info_del(DriveInfo *dinfo); static BlockBackend *bdrv_first_blk(BlockDriverState *bs); +static char *blk_get_attached_dev_id(BlockBackend *blk); /* All BlockBackends */ static QTAILQ_HEAD(, BlockBackend) block_backends = @@ -XXX,XX +XXX,XX @@ 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); +static char *blk_root_get_parent_desc(BdrvChild *child) +{ + BlockBackend *blk = child->opaque; + char *dev_id; + + if (blk->name) { + return g_strdup(blk->name); + } + + dev_id = blk_get_attached_dev_id(blk); + if (*dev_id) { + return dev_id; + } else { + /* TODO Callback into the BB owner for something more detailed */ + g_free(dev_id); + return g_strdup("a block device"); + } +} + static const char *blk_root_get_name(BdrvChild *child) { return blk_name(child->opaque); @@ -XXX,XX +XXX,XX @@ static const BdrvChildRole child_root = { .change_media = blk_root_change_media, .resize = blk_root_resize, .get_name = blk_root_get_name, + .get_parent_desc = blk_root_get_parent_desc, .drained_begin = blk_root_drained_begin, .drained_end = blk_root_drained_end, 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 @@ struct BdrvChildRole { * name), or NULL if the parent can't provide a better name. */ const char* (*get_name)(BdrvChild *child); + /* Returns a malloced string that describes the parent of the child for a + * human reader. This could be a node-name, BlockBackend name, qdev ID or + * QOM path of the device owning the BlockBackend, job type and ID etc. The + * caller is responsible for freeing the memory. */ + char* (*get_parent_desc)(BdrvChild *child); + /* * If this pair of functions is implemented, the parent doesn't issue new * requests after returning from .drained_begin() until .drained_end() is -- 1.8.3.1 Instead of just telling that there was some conflict, we can be specific and tell which permissions were in conflict and which way the conflict is. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 56 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 @@ static void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, *shared_perm = cumulative_shared_perms; } +static char *bdrv_child_user_desc(BdrvChild *c) +{ + if (c->role->get_parent_desc) { + return c->role->get_parent_desc(c); + } + + return g_strdup("another user"); +} + +static char *bdrv_perm_names(uint64_t perm) +{ + struct perm_name { + uint64_t perm; + const char *name; + } permissions[] = { + { BLK_PERM_CONSISTENT_READ, "consistent read" }, + { BLK_PERM_WRITE, "write" }, + { BLK_PERM_WRITE_UNCHANGED, "write unchanged" }, + { BLK_PERM_RESIZE, "resize" }, + { BLK_PERM_GRAPH_MOD, "change children" }, + { 0, NULL } + }; + + char *result = g_strdup(""); + struct perm_name *p; + + for (p = permissions; p->name; p++) { + if (perm & p->perm) { + char *old = result; + result = g_strdup_printf("%s%s%s", old, *old ? ", " : "", p->name); + g_free(old); + } + } + + return result; +} + /* * Checks whether a new reference to @bs can be added if the new user requires * @new_used_perm/@new_shared_perm as its permissions. If @ignore_child is set, @@ -XXX,XX +XXX,XX @@ static int bdrv_check_update_perm(BlockDriverState *bs, uint64_t new_used_perm, continue; } - if ((new_used_perm & c->shared_perm) != new_used_perm || - (c->perm & new_shared_perm) != c->perm) - { - const char *user = NULL; - if (c->role->get_name) { - user = c->role->get_name(c); - if (user && !*user) { - user = NULL; - } - } - error_setg(errp, "Conflicts with %s", user ?: "another operation"); + if ((new_used_perm & c->shared_perm) != new_used_perm) { + char *user = bdrv_child_user_desc(c); + char *perm_names = bdrv_perm_names(new_used_perm & ~c->shared_perm); + error_setg(errp, "Conflicts with use by %s as '%s', which does not " + "allow '%s' on %s", + user, c->name, perm_names, bdrv_get_node_name(c->bs)); + g_free(user); + g_free(perm_names); + return -EPERM; + } + + if ((c->perm & new_shared_perm) != c->perm) { + char *user = bdrv_child_user_desc(c); + char *perm_names = bdrv_perm_names(c->perm & ~new_shared_perm); + error_setg(errp, "Conflicts with use by %s as '%s', which uses " + "'%s' on %s", + user, c->name, perm_names, bdrv_get_node_name(c->bs)); + g_free(user); + g_free(perm_names); return -EPERM; } -- 1.8.3.1 When the parents' child links are updated in bdrv_append() or bdrv_replace_in_backing_chain(), this should affect all child links of BlockBackends or other nodes, but not on child links held for other purposes (like for setting permissions). This patch allows to control the behaviour per BdrvChildRole. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 3 +++ include/block/block_int.h | 4 ++++ 2 files 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 @@ static void change_parent_backing_link(BlockDriverState *from, BdrvChild *c, *next, *to_c; QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { + if (c->role->stay_at_node) { + continue; + } if (c->role == &child_backing) { /* @from is generally not allowed to be a backing file, except for * when @to is the overlay. In that case, @from may not be replaced 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 @@ typedef struct BdrvAioNotifier { } BdrvAioNotifier; struct BdrvChildRole { + /* If true, bdrv_replace_in_backing_chain() doesn't change the node this + * BdrvChild points to. */ + bool stay_at_node; + void (*inherit_options)(int *child_flags, QDict *child_options, int parent_flags, QDict *parent_options); -- 1.8.3.1 Block jobs don't actually do I/O through the the reference they create with block_job_add_bdrv(), but they might want to use the permisssion system to express what the block job does to intermediate nodes. This adds permissions to block_job_add_bdrv() to provide the means to request permissions. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/backup.c | 4 +++- block/commit.c | 8 ++++++-- block/mirror.c | 9 +++++++-- block/stream.c | 4 +++- blockjob.c | 36 ++++++++++++++++++++++++++++++------ include/block/blockjob.h | 5 ++++- 6 files changed, 53 insertions(+), 13 deletions(-) diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size); } - block_job_add_bdrv(&job->common, target); + /* FIXME Use real permissions */ + block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL, + &error_abort); job->common.len = len; block_job_txn_add_job(txn, &job->common); 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 @@ void commit_start(const char *job_id, BlockDriverState *bs, * disappear from the chain after this operation. */ assert(bdrv_chain_contains(top, base)); for (iter = top; iter != backing_bs(base); iter = backing_bs(iter)) { - block_job_add_bdrv(&s->common, iter); + /* FIXME Use real permissions */ + block_job_add_bdrv(&s->common, "intermediate node", iter, 0, + BLK_PERM_ALL, &error_abort); } /* overlay_bs must be blocked because it needs to be modified to * update the backing image string, but if it's the root node then * don't block it again */ if (bs != overlay_bs) { - block_job_add_bdrv(&s->common, overlay_bs); + /* FIXME Use real permissions */ + block_job_add_bdrv(&s->common, "overlay of top", overlay_bs, 0, + BLK_PERM_ALL, &error_abort); } /* FIXME Use real permissions */ diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, return; } - block_job_add_bdrv(&s->common, target); + /* FIXME Use real permissions */ + block_job_add_bdrv(&s->common, "target", target, 0, BLK_PERM_ALL, + &error_abort); + /* In commit_active_start() all intermediate nodes disappear, so * any jobs in them must be blocked */ if (bdrv_chain_contains(bs, target)) { BlockDriverState *iter; for (iter = backing_bs(bs); iter != target; iter = backing_bs(iter)) { - block_job_add_bdrv(&s->common, iter); + /* FIXME Use real permissions */ + block_job_add_bdrv(&s->common, "intermediate node", iter, 0, + BLK_PERM_ALL, &error_abort); } } 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 @@ void stream_start(const char *job_id, BlockDriverState *bs, /* Block all intermediate nodes between bs and base, because they * will disappear from the chain after this operation */ for (iter = backing_bs(bs); iter && iter != base; iter = backing_bs(iter)) { - block_job_add_bdrv(&s->common, iter); + /* FIXME Use real permissions */ + block_job_add_bdrv(&s->common, "intermediate node", iter, 0, + BLK_PERM_ALL, &error_abort); } s->base = base; diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ struct BlockJobTxn { static QLIST_HEAD(, BlockJob) block_jobs = QLIST_HEAD_INITIALIZER(block_jobs); +static char *child_job_get_parent_desc(BdrvChild *c) +{ + BlockJob *job = c->opaque; + return g_strdup_printf("%s job '%s'", + BlockJobType_lookup[job->driver->job_type], + job->id); +} + +static const BdrvChildRole child_job = { + .get_parent_desc = child_job_get_parent_desc, + .stay_at_node = true, +}; + BlockJob *block_job_next(BlockJob *job) { if (!job) { @@ -XXX,XX +XXX,XX @@ static void block_job_detach_aio_context(void *opaque) block_job_unref(job); } -void block_job_add_bdrv(BlockJob *job, BlockDriverState *bs) +int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, + uint64_t perm, uint64_t shared_perm, Error **errp) { - job->nodes = g_slist_prepend(job->nodes, bs); + BdrvChild *c; + + c = bdrv_root_attach_child(bs, name, &child_job, perm, shared_perm, + job, errp); + if (c == NULL) { + return -EPERM; + } + + job->nodes = g_slist_prepend(job->nodes, c); bdrv_ref(bs); bdrv_op_block_all(bs, job->blocker); + + return 0; } void *block_job_create(const char *job_id, const BlockJobDriver *driver, @@ -XXX,XX +XXX,XX @@ void *block_job_create(const char *job_id, const BlockJobDriver *driver, job = g_malloc0(driver->instance_size); error_setg(&job->blocker, "block device is in use by block job: %s", BlockJobType_lookup[driver->job_type]); - block_job_add_bdrv(job, bs); + block_job_add_bdrv(job, "main node", bs, 0, BLK_PERM_ALL, &error_abort); bdrv_op_unblock(bs, BLOCK_OP_TYPE_DATAPLANE, job->blocker); job->driver = driver; @@ -XXX,XX +XXX,XX @@ void block_job_unref(BlockJob *job) BlockDriverState *bs = blk_bs(job->blk); bs->job = NULL; for (l = job->nodes; l; l = l->next) { - bs = l->data; - bdrv_op_unblock_all(bs, job->blocker); - bdrv_unref(bs); + BdrvChild *c = l->data; + bdrv_op_unblock_all(c->bs, job->blocker); + bdrv_root_unref_child(c); } g_slist_free(job->nodes); blk_remove_aio_context_notifier(job->blk, diff --git a/include/block/blockjob.h b/include/block/blockjob.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/blockjob.h +++ b/include/block/blockjob.h @@ -XXX,XX +XXX,XX @@ BlockJob *block_job_get(const char *id); /** * block_job_add_bdrv: * @job: A block job + * @name: The name to assign to the new BdrvChild * @bs: A BlockDriverState that is involved in @job + * @perm, @shared_perm: Permissions to request on the node * * Add @bs to the list of BlockDriverState that are involved in * @job. This means that all operations will be blocked on @bs while * @job exists. */ -void block_job_add_bdrv(BlockJob *job, BlockDriverState *bs); +int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, + uint64_t perm, uint64_t shared_perm, Error **errp); /** * block_job_set_speed: -- 1.8.3.1 This is probably one of the most interesting conversions to the new op blocker system because a commit block job intentionally leaves some intermediate block nodes in the backing chain that aren't valid on their own any more; only the whole chain together results in a valid view. In order to provide the 'consistent read' permission to the parents of the 'top' node of the commit job, a new filter block driver is inserted above 'top' which doesn't require 'consistent read' on its backing chain. Subsequently, the commit job can block 'consistent read' on all intermediate nodes without causing a conflict. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block/commit.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 95 insertions(+), 18 deletions(-) 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 @@ typedef struct CommitBlockJob { BlockJob common; RateLimit limit; BlockDriverState *active; + BlockDriverState *commit_top_bs; BlockBackend *top; BlockBackend *base; BlockdevOnError on_error; @@ -XXX,XX +XXX,XX @@ static void commit_complete(BlockJob *job, void *opaque) BlockDriverState *active = s->active; BlockDriverState *top = blk_bs(s->top); BlockDriverState *base = blk_bs(s->base); - BlockDriverState *overlay_bs = bdrv_find_overlay(active, top); + BlockDriverState *overlay_bs = bdrv_find_overlay(active, s->commit_top_bs); int ret = data->ret; + bool remove_commit_top_bs = false; + + /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before + * the normal backing chain can be restored. */ + blk_unref(s->base); if (!block_job_is_cancelled(&s->common) && ret == 0) { /* success */ - ret = bdrv_drop_intermediate(active, top, base, s->backing_file_str); + ret = bdrv_drop_intermediate(active, s->commit_top_bs, base, + s->backing_file_str); + } else if (overlay_bs) { + /* XXX Can (or should) we somehow keep 'consistent read' blocked even + * after the failed/cancelled commit job is gone? If we already wrote + * something to base, the intermediate images aren't valid any more. */ + remove_commit_top_bs = true; } /* restore base open flags here if appropriate (e.g., change the base back @@ -XXX,XX +XXX,XX @@ static void commit_complete(BlockJob *job, void *opaque) } g_free(s->backing_file_str); blk_unref(s->top); - blk_unref(s->base); block_job_completed(&s->common, ret); g_free(data); + + /* If bdrv_drop_intermediate() didn't already do that, remove the commit + * filter driver from the backing chain. Do this as the final step so that + * the 'consistent read' permission can be granted. */ + if (remove_commit_top_bs) { + bdrv_set_backing_hd(overlay_bs, top); + } } static void coroutine_fn commit_run(void *opaque) @@ -XXX,XX +XXX,XX @@ static const BlockJobDriver commit_job_driver = { .start = commit_run, }; +static int coroutine_fn bdrv_commit_top_preadv(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) +{ + return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags); +} + +static void bdrv_commit_top_close(BlockDriverState *bs) +{ +} + +static void bdrv_commit_top_child_perm(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + *nperm = 0; + *nshared = BLK_PERM_ALL; +} + +/* Dummy node that provides consistent read to its users without requiring it + * from its backing file and that allows writes on the backing file chain. */ +static BlockDriver bdrv_commit_top = { + .format_name = "commit_top", + .bdrv_co_preadv = bdrv_commit_top_preadv, + .bdrv_close = bdrv_commit_top_close, + .bdrv_child_perm = bdrv_commit_top_child_perm, +}; + void commit_start(const char *job_id, BlockDriverState *bs, BlockDriverState *base, BlockDriverState *top, int64_t speed, BlockdevOnError on_error, const char *backing_file_str, @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, int orig_base_flags; BlockDriverState *iter; BlockDriverState *overlay_bs; + BlockDriverState *commit_top_bs = NULL; Error *local_err = NULL; int ret; @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, return; } - /* FIXME Use real permissions */ s = block_job_create(job_id, &commit_job_driver, bs, 0, BLK_PERM_ALL, speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp); if (!s) { @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, } } + /* Insert commit_top block node above top, so we can block consistent read + * on the backing chain below it */ + commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, NULL, 0, errp); + if (commit_top_bs == NULL) { + goto fail; + } + + bdrv_set_backing_hd(commit_top_bs, top); + bdrv_set_backing_hd(overlay_bs, commit_top_bs); + + s->commit_top_bs = commit_top_bs; + bdrv_unref(commit_top_bs); /* Block all nodes between top and base, because they will * disappear from the chain after this operation. */ assert(bdrv_chain_contains(top, base)); - for (iter = top; iter != backing_bs(base); iter = backing_bs(iter)) { - /* FIXME Use real permissions */ - block_job_add_bdrv(&s->common, "intermediate node", iter, 0, - BLK_PERM_ALL, &error_abort); + for (iter = top; iter != base; iter = backing_bs(iter)) { + /* XXX BLK_PERM_WRITE needs to be allowed so we don't block ourselves + * at s->base (if writes are blocked for a node, they are also blocked + * for its backing file). The other options would be a second filter + * driver above s->base. */ + ret = block_job_add_bdrv(&s->common, "intermediate node", iter, 0, + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE, + errp); + if (ret < 0) { + goto fail; + } } + + ret = block_job_add_bdrv(&s->common, "base", base, 0, BLK_PERM_ALL, errp); + if (ret < 0) { + goto fail; + } + /* overlay_bs must be blocked because it needs to be modified to - * update the backing image string, but if it's the root node then - * don't block it again */ - if (bs != overlay_bs) { - /* FIXME Use real permissions */ - block_job_add_bdrv(&s->common, "overlay of top", overlay_bs, 0, - BLK_PERM_ALL, &error_abort); + * update the backing image string. */ + ret = block_job_add_bdrv(&s->common, "overlay of top", overlay_bs, + BLK_PERM_GRAPH_MOD, BLK_PERM_ALL, errp); + if (ret < 0) { + goto fail; } - /* FIXME Use real permissions */ - s->base = blk_new(0, BLK_PERM_ALL); + s->base = blk_new(BLK_PERM_CONSISTENT_READ + | BLK_PERM_WRITE + | BLK_PERM_RESIZE, + BLK_PERM_CONSISTENT_READ + | BLK_PERM_GRAPH_MOD + | BLK_PERM_WRITE_UNCHANGED); ret = blk_insert_bs(s->base, base, errp); if (ret < 0) { goto fail; } - /* FIXME Use real permissions */ + /* Required permissions are already taken with block_job_add_bdrv() */ s->top = blk_new(0, BLK_PERM_ALL); - ret = blk_insert_bs(s->top, top, errp); + blk_insert_bs(s->top, top, errp); if (ret < 0) { goto fail; } @@ -XXX,XX +XXX,XX @@ fail: if (s->top) { blk_unref(s->top); } + if (commit_top_bs) { + bdrv_set_backing_hd(overlay_bs, top); + } block_job_unref(&s->common); } -- 1.8.3.1 This is a little simpler than the commit block job because it's synchronous and only commits into the immediate backing file, but otherwise doing more or less the same. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/commit.c | 33 +++++++++++++++++++++++++++------ 1 file changed, 27 insertions(+), 6 deletions(-) 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 @@ fail: int bdrv_commit(BlockDriverState *bs) { BlockBackend *src, *backing; + BlockDriverState *backing_file_bs = NULL; + BlockDriverState *commit_top_bs = NULL; BlockDriver *drv = bs->drv; int64_t sector, total_sectors, length, backing_length; int n, ro, open_flags; int ret = 0; uint8_t *buf = NULL; + Error *local_err = NULL; if (!drv) return -ENOMEDIUM; @@ -XXX,XX +XXX,XX @@ int bdrv_commit(BlockDriverState *bs) } } - /* FIXME Use real permissions */ - src = blk_new(0, BLK_PERM_ALL); - backing = blk_new(0, BLK_PERM_ALL); + src = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); + backing = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL); - ret = blk_insert_bs(src, bs, NULL); + ret = blk_insert_bs(src, bs, &local_err); if (ret < 0) { + error_report_err(local_err); + goto ro_cleanup; + } + + /* Insert commit_top block node above backing, so we can write to it */ + backing_file_bs = backing_bs(bs); + + commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, NULL, BDRV_O_RDWR, + &local_err); + if (commit_top_bs == NULL) { + error_report_err(local_err); goto ro_cleanup; } - ret = blk_insert_bs(backing, bs->backing->bs, NULL); + bdrv_set_backing_hd(commit_top_bs, backing_file_bs); + bdrv_set_backing_hd(bs, commit_top_bs); + + ret = blk_insert_bs(backing, backing_file_bs, &local_err); if (ret < 0) { + error_report_err(local_err); goto ro_cleanup; } @@ -XXX,XX +XXX,XX @@ int bdrv_commit(BlockDriverState *bs) ro_cleanup: qemu_vfree(buf); - blk_unref(src); blk_unref(backing); + if (backing_file_bs) { + bdrv_set_backing_hd(bs, backing_file_bs); + } + bdrv_unref(commit_top_bs); + blk_unref(src); if (ro) { /* ignoring error return here */ -- 1.8.3.1 The backup block job doesn't have very complicated requirements: It needs to read from the source and write to the target, but it's fine with either side being changed. The only restriction is that we can't resize the image because the job uses a cached value. qemu-iotests 055 needs to be changed because it used a target which was already attached to a virtio-blk device. The permission system correctly forbids this (virtio-blk can't accept another writer with its default share-rw=off). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/backup.c | 15 ++++++++++----- tests/qemu-iotests/055 | 11 +++++++---- 2 files changed, 17 insertions(+), 9 deletions(-) diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, goto error; } - /* FIXME Use real permissions */ - job = block_job_create(job_id, &backup_job_driver, bs, 0, BLK_PERM_ALL, + /* job->common.len is fixed, so we can't allow resize */ + job = block_job_create(job_id, &backup_job_driver, bs, + BLK_PERM_CONSISTENT_READ, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD, speed, creation_flags, cb, opaque, errp); if (!job) { goto error; } - /* FIXME Use real permissions */ - job->target = blk_new(0, BLK_PERM_ALL); + /* The target must match the source in size, so no resize here either */ + job->target = blk_new(BLK_PERM_WRITE, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE | + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_GRAPH_MOD); ret = blk_insert_bs(job->target, target, errp); if (ret < 0) { goto error; @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, job->cluster_size = MAX(BACKUP_CLUSTER_SIZE_DEFAULT, bdi.cluster_size); } - /* FIXME Use real permissions */ + /* Required permissions are already taken with target's blk_new() */ block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL, &error_abort); job->common.len = len; diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/055 +++ b/tests/qemu-iotests/055 @@ -XXX,XX +XXX,XX @@ class TestSingleDrive(iotests.QMPTestCase): def setUp(self): qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(image_len)) - self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img) + self.vm = iotests.VM().add_drive(test_img) + self.vm.add_drive(blockdev_target_img, interface="none") if iotests.qemu_default_machine == 'pc': self.vm.add_drive(None, 'media=cdrom', 'ide') self.vm.launch() @@ -XXX,XX +XXX,XX @@ class TestSetSpeed(iotests.QMPTestCase): def setUp(self): qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(image_len)) - self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img) + self.vm = iotests.VM().add_drive(test_img) + self.vm.add_drive(blockdev_target_img, interface="none") self.vm.launch() def tearDown(self): @@ -XXX,XX +XXX,XX @@ class TestSingleTransaction(iotests.QMPTestCase): def setUp(self): qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(image_len)) - self.vm = iotests.VM().add_drive(test_img).add_drive(blockdev_target_img) + self.vm = iotests.VM().add_drive(test_img) + self.vm.add_drive(blockdev_target_img, interface="none") if iotests.qemu_default_machine == 'pc': self.vm.add_drive(None, 'media=cdrom', 'ide') self.vm.launch() @@ -XXX,XX +XXX,XX @@ class TestDriveCompression(iotests.QMPTestCase): qemu_img('create', '-f', fmt, blockdev_target_img, str(TestDriveCompression.image_len), *args) - self.vm.add_drive(blockdev_target_img, format=fmt) + self.vm.add_drive(blockdev_target_img, format=fmt, interface="none") self.vm.launch() -- 1.8.3.1 bdrv_append() cares about isolation of the node that it modifies, but not about activity in some subtree below it. Instead of using the recursive bdrv_requests_pending(), directly check bs->in_flight, which considers only the node in question. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@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 @@ static void change_parent_backing_link(BlockDriverState *from, */ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) { - assert(!bdrv_requests_pending(bs_top)); - assert(!bdrv_requests_pending(bs_new)); + assert(!atomic_read(&bs_top->in_flight)); + assert(!atomic_read(&bs_new->in_flight)); bdrv_ref(bs_top); -- 1.8.3.1 Backing files are somewhat special compared to other kinds of children because they are attached and detached using bdrv_set_backing_hd() rather than the normal set of functions, which does a few more things like setting backing blockers, toggling the BDRV_O_NO_BACKING flag, setting parent_bs->backing_file, etc. These special features are a reason why change_parent_backing_link() can't handle backing files yet. With abstracting the additional features into .attach/.detach callbacks, we get a step closer to a function that can actually deal with this. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 95 ++++++++++++++++++++++++++++++----------------- include/block/block_int.h | 3 ++ 2 files changed, 63 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 @@ const BdrvChildRole child_format = { .drained_end = bdrv_child_cb_drained_end, }; +static void bdrv_backing_attach(BdrvChild *c) +{ + BlockDriverState *parent = c->opaque; + BlockDriverState *backing_hd = c->bs; + + assert(!parent->backing_blocker); + error_setg(&parent->backing_blocker, + "node is used as backing hd of '%s'", + bdrv_get_device_or_node_name(parent)); + + parent->open_flags &= ~BDRV_O_NO_BACKING; + pstrcpy(parent->backing_file, sizeof(parent->backing_file), + backing_hd->filename); + pstrcpy(parent->backing_format, sizeof(parent->backing_format), + backing_hd->drv ? backing_hd->drv->format_name : ""); + + bdrv_op_block_all(backing_hd, parent->backing_blocker); + /* Otherwise we won't be able to commit or stream */ + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, + parent->backing_blocker); + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, + parent->backing_blocker); + /* + * We do backup in 3 ways: + * 1. drive backup + * The target bs is new opened, and the source is top BDS + * 2. blockdev backup + * Both the source and the target are top BDSes. + * 3. internal backup(used for block replication) + * Both the source and the target are backing file + * + * In case 1 and 2, neither the source nor the target is the backing file. + * In case 3, we will block the top BDS, so there is only one block job + * for the top BDS and its backing chain. + */ + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, + parent->backing_blocker); + bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, + parent->backing_blocker); +} + +static void bdrv_backing_detach(BdrvChild *c) +{ + BlockDriverState *parent = c->opaque; + + assert(parent->backing_blocker); + bdrv_op_unblock_all(c->bs, parent->backing_blocker); + error_free(parent->backing_blocker); + parent->backing_blocker = NULL; +} + /* * Returns the options and flags that bs->backing should get, based on the * given options and flags for the parent BDS @@ -XXX,XX +XXX,XX @@ static void bdrv_backing_options(int *child_flags, QDict *child_options, const BdrvChildRole child_backing = { .get_parent_desc = bdrv_child_get_parent_desc, + .attach = bdrv_backing_attach, + .detach = bdrv_backing_detach, .inherit_options = bdrv_backing_options, .drained_begin = bdrv_child_cb_drained_begin, .drained_end = bdrv_child_cb_drained_end, @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, if (old_bs->quiesce_counter && child->role->drained_end) { child->role->drained_end(child); } + if (child->role->detach) { + child->role->detach(child); + } QLIST_REMOVE(child, next_parent); /* Update permissions for old node. This is guaranteed to succeed @@ -XXX,XX +XXX,XX @@ static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs, bdrv_check_perm(new_bs, perm, shared_perm, &error_abort); } bdrv_set_perm(new_bs, perm, shared_perm); + + if (child->role->attach) { + child->role->attach(child); + } } } @@ -XXX,XX +XXX,XX @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) } if (bs->backing) { - assert(bs->backing_blocker); - bdrv_op_unblock_all(bs->backing->bs, bs->backing_blocker); bdrv_unref_child(bs, bs->backing); - } else if (backing_hd) { - error_setg(&bs->backing_blocker, - "node is used as backing hd of '%s'", - bdrv_get_device_or_node_name(bs)); } if (!backing_hd) { - error_free(bs->backing_blocker); - bs->backing_blocker = NULL; bs->backing = NULL; goto out; } /* FIXME Error handling */ bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, &error_abort); - bs->open_flags &= ~BDRV_O_NO_BACKING; - pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename); - pstrcpy(bs->backing_format, sizeof(bs->backing_format), - backing_hd->drv ? backing_hd->drv->format_name : ""); - bdrv_op_block_all(backing_hd, bs->backing_blocker); - /* Otherwise we won't be able to commit or stream */ - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, - bs->backing_blocker); - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, - bs->backing_blocker); - /* - * We do backup in 3 ways: - * 1. drive backup - * The target bs is new opened, and the source is top BDS - * 2. blockdev backup - * Both the source and the target are top BDSes. - * 3. internal backup(used for block replication) - * Both the source and the target are backing file - * - * In case 1 and 2, neither the source nor the target is the backing file. - * In case 3, we will block the top BDS, so there is only one block job - * for the top BDS and its backing chain. - */ - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, - bs->backing_blocker); - bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, - bs->backing_blocker); out: bdrv_refresh_limits(bs, NULL); } 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 @@ struct BdrvChildRole { */ void (*drained_begin)(BdrvChild *child); void (*drained_end)(BdrvChild *child); + + void (*attach)(BdrvChild *child); + void (*detach)(BdrvChild *child); }; extern const BdrvChildRole child_file; -- 1.8.3.1 Now that the backing file child role implements .attach/.detach callbacks, nothing prevents us from modifying the graph even if that involves changing backing file links. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@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 @@ static void change_parent_backing_link(BlockDriverState *from, continue; } if (c->role == &child_backing) { - /* @from is generally not allowed to be a backing file, except for - * when @to is the overlay. In that case, @from may not be replaced - * by @to as @to's backing node. */ + /* If @from is a backing file of @to, ignore the child to avoid + * creating a loop. We only want to change the pointer of other + * parents. */ QLIST_FOREACH(to_c, &to->children, next) { if (to_c == c) { break; @@ -XXX,XX +XXX,XX @@ static void change_parent_backing_link(BlockDriverState *from, } } - assert(c->role != &child_backing); bdrv_ref(to); /* FIXME Are we sure that bdrv_replace_child() can't run into * &error_abort because of permissions? */ -- 1.8.3.1 In some cases, we want to remove op blockers on intermediate nodes before the whole block job transaction has completed (because they block restoring the final graph state during completion). Provide a function for this. The whole block job lifecycle is a bit messed up and it's hard to actually do all things in the right order, but I'll leave simplifying this for another day. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- blockjob.c | 20 +++++++++++++------- include/block/blockjob.h | 9 +++++++++ 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/blockjob.c b/blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/blockjob.c +++ b/blockjob.c @@ -XXX,XX +XXX,XX @@ static void block_job_detach_aio_context(void *opaque) block_job_unref(job); } +void block_job_remove_all_bdrv(BlockJob *job) +{ + GSList *l; + for (l = job->nodes; l; l = l->next) { + BdrvChild *c = l->data; + bdrv_op_unblock_all(c->bs, job->blocker); + bdrv_root_unref_child(c); + } + g_slist_free(job->nodes); + job->nodes = NULL; +} + int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, uint64_t perm, uint64_t shared_perm, Error **errp) { @@ -XXX,XX +XXX,XX @@ void block_job_ref(BlockJob *job) void block_job_unref(BlockJob *job) { if (--job->refcnt == 0) { - GSList *l; BlockDriverState *bs = blk_bs(job->blk); bs->job = NULL; - for (l = job->nodes; l; l = l->next) { - BdrvChild *c = l->data; - bdrv_op_unblock_all(c->bs, job->blocker); - bdrv_root_unref_child(c); - } - g_slist_free(job->nodes); + block_job_remove_all_bdrv(job); blk_remove_aio_context_notifier(job->blk, block_job_attached_aio_context, block_job_detach_aio_context, job); diff --git a/include/block/blockjob.h b/include/block/blockjob.h index XXXXXXX..XXXXXXX 100644 --- a/include/block/blockjob.h +++ b/include/block/blockjob.h @@ -XXX,XX +XXX,XX @@ int block_job_add_bdrv(BlockJob *job, const char *name, BlockDriverState *bs, uint64_t perm, uint64_t shared_perm, Error **errp); /** + * block_job_remove_all_bdrv: + * @job: The block job + * + * Remove all BlockDriverStates from the list of nodes that are involved in the + * job. This removes the blockers added with block_job_add_bdrv(). + */ +void block_job_remove_all_bdrv(BlockJob *job); + +/** * block_job_set_speed: * @job: The job to set the speed for. * @speed: The new value -- 1.8.3.1 The mirror block job is mainly used for two different scenarios: Mirroring to an otherwise unused, independent target node, or for active commit where the target node is part of the backing chain of the source. Similarly to the commit block job patch, we need to insert a new filter node to keep the permissions correct during active commit. Note that one change this implies is that job->blk points to mirror_top_bs as its root now, and mirror_top_bs (rather than the actual source node) contains the bs->job pointer. This requires qemu-img commit to get the job by name now rather than just taking bs->job. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Acked-by: Max Reitz <mreitz@redhat.com> --- block/mirror.c | 216 ++++++++++++++++++++++++++++++++++++++------- qemu-img.c | 6 +- tests/qemu-iotests/141 | 2 +- tests/qemu-iotests/141.out | 4 +- 4 files changed, 190 insertions(+), 38 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ typedef struct MirrorBlockJob { BlockJob common; RateLimit limit; BlockBackend *target; + BlockDriverState *mirror_top_bs; + BlockDriverState *source; BlockDriverState *base; + /* The name of the graph node to replace */ char *replaces; /* The BDS to replace */ @@ -XXX,XX +XXX,XX @@ static void mirror_do_zero_or_discard(MirrorBlockJob *s, static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) { - BlockDriverState *source = blk_bs(s->common.blk); + BlockDriverState *source = s->source; int64_t sector_num, first_chunk; uint64_t delay_ns = 0; /* At least the first dirty chunk is mirrored in one iteration. */ @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); MirrorExitData *data = opaque; AioContext *replace_aio_context = NULL; - BlockDriverState *src = blk_bs(s->common.blk); + BlockDriverState *src = s->source; BlockDriverState *target_bs = blk_bs(s->target); + BlockDriverState *mirror_top_bs = s->mirror_top_bs; /* Make sure that the source BDS doesn't go away before we called * block_job_completed(). */ bdrv_ref(src); + bdrv_ref(mirror_top_bs); + + /* We don't access the source any more. Dropping any WRITE/RESIZE is + * required before it could become a backing file of target_bs. */ + bdrv_child_try_set_perm(mirror_top_bs->backing, 0, BLK_PERM_ALL, + &error_abort); + if (s->backing_mode == MIRROR_SOURCE_BACKING_CHAIN) { + BlockDriverState *backing = s->is_none_mode ? src : s->base; + if (backing_bs(target_bs) != backing) { + bdrv_set_backing_hd(target_bs, backing); + } + } if (s->to_replace) { replace_aio_context = bdrv_get_aio_context(s->to_replace); @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) bdrv_drained_begin(target_bs); bdrv_replace_in_backing_chain(to_replace, target_bs); bdrv_drained_end(target_bs); - - /* We just changed the BDS the job BB refers to, so switch the BB back - * so the cleanup does the right thing. We don't need any permissions - * any more now. */ - blk_remove_bs(job->blk); - blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort); - blk_insert_bs(job->blk, src, &error_abort); } if (s->to_replace) { bdrv_op_unblock_all(s->to_replace, s->replace_blocker); @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) g_free(s->replaces); blk_unref(s->target); s->target = NULL; + + /* Remove the mirror filter driver from the graph. Before this, get rid of + * the blockers on the intermediate nodes so that the resulting state is + * valid. */ + block_job_remove_all_bdrv(job); + bdrv_replace_in_backing_chain(mirror_top_bs, backing_bs(mirror_top_bs)); + + /* We just changed the BDS the job BB refers to (with either or both of the + * bdrv_replace_in_backing_chain() calls), so switch the BB back so the + * cleanup does the right thing. We don't need any permissions any more + * now. */ + blk_remove_bs(job->blk); + blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort); + blk_insert_bs(job->blk, mirror_top_bs, &error_abort); + block_job_completed(&s->common, data->ret); + g_free(data); bdrv_drained_end(src); + bdrv_unref(mirror_top_bs); bdrv_unref(src); } @@ -XXX,XX +XXX,XX @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) { int64_t sector_num, end; BlockDriverState *base = s->base; - BlockDriverState *bs = blk_bs(s->common.blk); + BlockDriverState *bs = s->source; BlockDriverState *target_bs = blk_bs(s->target); int ret, n; @@ -XXX,XX +XXX,XX @@ static void coroutine_fn mirror_run(void *opaque) { MirrorBlockJob *s = opaque; MirrorExitData *data; - BlockDriverState *bs = blk_bs(s->common.blk); + BlockDriverState *bs = s->source; BlockDriverState *target_bs = blk_bs(s->target); bool need_drain = true; int64_t length; @@ -XXX,XX +XXX,XX @@ static void mirror_set_speed(BlockJob *job, int64_t speed, Error **errp) static void mirror_complete(BlockJob *job, Error **errp) { MirrorBlockJob *s = container_of(job, MirrorBlockJob, common); - BlockDriverState *src, *target; + BlockDriverState *target; - src = blk_bs(job->blk); target = blk_bs(s->target); if (!s->synced) { @@ -XXX,XX +XXX,XX @@ static void mirror_complete(BlockJob *job, Error **errp) replace_aio_context = bdrv_get_aio_context(s->to_replace); aio_context_acquire(replace_aio_context); + /* TODO Translate this into permission system. Current definition of + * GRAPH_MOD would require to request it for the parents; they might + * not even be BlockDriverStates, however, so a BdrvChild can't address + * them. May need redefinition of GRAPH_MOD. */ error_setg(&s->replace_blocker, "block device is in use by block-job-complete"); bdrv_op_block_all(s->to_replace, s->replace_blocker); @@ -XXX,XX +XXX,XX @@ static void mirror_complete(BlockJob *job, Error **errp) aio_context_release(replace_aio_context); } - if (s->backing_mode == MIRROR_SOURCE_BACKING_CHAIN) { - BlockDriverState *backing = s->is_none_mode ? src : s->base; - if (backing_bs(target) != backing) { - bdrv_set_backing_hd(target, backing); - } - } - s->should_complete = true; block_job_enter(&s->common); } @@ -XXX,XX +XXX,XX @@ static const BlockJobDriver commit_active_job_driver = { .drain = mirror_drain, }; +static int coroutine_fn bdrv_mirror_top_preadv(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) +{ + return bdrv_co_preadv(bs->backing, offset, bytes, qiov, flags); +} + +static int coroutine_fn bdrv_mirror_top_pwritev(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) +{ + return bdrv_co_pwritev(bs->backing, offset, bytes, qiov, flags); +} + +static int coroutine_fn bdrv_mirror_top_flush(BlockDriverState *bs) +{ + return bdrv_co_flush(bs->backing->bs); +} + +static int64_t coroutine_fn bdrv_mirror_top_get_block_status( + BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum, + BlockDriverState **file) +{ + *pnum = nb_sectors; + *file = bs->backing->bs; + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | BDRV_BLOCK_DATA | + (sector_num << BDRV_SECTOR_BITS); +} + +static int coroutine_fn bdrv_mirror_top_pwrite_zeroes(BlockDriverState *bs, + int64_t offset, int count, BdrvRequestFlags flags) +{ + return bdrv_co_pwrite_zeroes(bs->backing, offset, count, flags); +} + +static int coroutine_fn bdrv_mirror_top_pdiscard(BlockDriverState *bs, + int64_t offset, int count) +{ + return bdrv_co_pdiscard(bs->backing->bs, offset, count); +} + +static void bdrv_mirror_top_close(BlockDriverState *bs) +{ +} + +static void bdrv_mirror_top_child_perm(BlockDriverState *bs, BdrvChild *c, + const BdrvChildRole *role, + uint64_t perm, uint64_t shared, + uint64_t *nperm, uint64_t *nshared) +{ + /* Must be able to forward guest writes to the real image */ + *nperm = 0; + if (perm & BLK_PERM_WRITE) { + *nperm |= BLK_PERM_WRITE; + } + + *nshared = BLK_PERM_ALL; +} + +/* Dummy node that provides consistent read to its users without requiring it + * from its backing file and that allows writes on the backing file chain. */ +static BlockDriver bdrv_mirror_top = { + .format_name = "mirror_top", + .bdrv_co_preadv = bdrv_mirror_top_preadv, + .bdrv_co_pwritev = bdrv_mirror_top_pwritev, + .bdrv_co_pwrite_zeroes = bdrv_mirror_top_pwrite_zeroes, + .bdrv_co_pdiscard = bdrv_mirror_top_pdiscard, + .bdrv_co_flush = bdrv_mirror_top_flush, + .bdrv_co_get_block_status = bdrv_mirror_top_get_block_status, + .bdrv_close = bdrv_mirror_top_close, + .bdrv_child_perm = bdrv_mirror_top_child_perm, +}; + static void mirror_start_job(const char *job_id, BlockDriverState *bs, int creation_flags, BlockDriverState *target, const char *replaces, int64_t speed, @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, bool auto_complete) { MirrorBlockJob *s; + BlockDriverState *mirror_top_bs; + bool target_graph_mod; + bool target_is_backing; int ret; if (granularity == 0) { @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, buf_size = DEFAULT_MIRROR_BUF_SIZE; } - /* FIXME Use real permissions */ - s = block_job_create(job_id, driver, bs, 0, BLK_PERM_ALL, speed, + /* In the case of active commit, add dummy driver to provide consistent + * reads on the top, while disabling it in the intermediate nodes, and make + * the backing chain writable. */ + mirror_top_bs = bdrv_new_open_driver(&bdrv_mirror_top, NULL, BDRV_O_RDWR, + errp); + if (mirror_top_bs == NULL) { + return; + } + mirror_top_bs->total_sectors = bs->total_sectors; + + /* bdrv_append takes ownership of the mirror_top_bs reference, need to keep + * it alive until block_job_create() even if bs has no parent. */ + bdrv_ref(mirror_top_bs); + bdrv_drained_begin(bs); + bdrv_append(mirror_top_bs, bs); + bdrv_drained_end(bs); + + /* Make sure that the source is not resized while the job is running */ + s = block_job_create(job_id, driver, mirror_top_bs, + BLK_PERM_CONSISTENT_READ, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | + BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD, speed, creation_flags, cb, opaque, errp); + bdrv_unref(mirror_top_bs); if (!s) { - return; + goto fail; } - - /* FIXME Use real permissions */ - s->target = blk_new(0, BLK_PERM_ALL); + s->source = bs; + s->mirror_top_bs = mirror_top_bs; + + /* No resize for the target either; while the mirror is still running, a + * consistent read isn't necessarily possible. We could possibly allow + * writes and graph modifications, though it would likely defeat the + * purpose of a mirror, so leave them blocked for now. + * + * In the case of active commit, things look a bit different, though, + * because the target is an already populated backing file in active use. + * We can allow anything except resize there.*/ + target_is_backing = bdrv_chain_contains(bs, target); + target_graph_mod = (backing_mode != MIRROR_LEAVE_BACKING_CHAIN); + s->target = blk_new(BLK_PERM_WRITE | BLK_PERM_RESIZE | + (target_graph_mod ? BLK_PERM_GRAPH_MOD : 0), + BLK_PERM_WRITE_UNCHANGED | + (target_is_backing ? BLK_PERM_CONSISTENT_READ | + BLK_PERM_WRITE | + BLK_PERM_GRAPH_MOD : 0)); ret = blk_insert_bs(s->target, target, errp); if (ret < 0) { - blk_unref(s->target); - block_job_unref(&s->common); - return; + goto fail; } s->replaces = g_strdup(replaces); @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, return; } - /* FIXME Use real permissions */ + /* Required permissions are already taken with blk_new() */ block_job_add_bdrv(&s->common, "target", target, 0, BLK_PERM_ALL, &error_abort); /* In commit_active_start() all intermediate nodes disappear, so * any jobs in them must be blocked */ - if (bdrv_chain_contains(bs, target)) { + if (target_is_backing) { BlockDriverState *iter; for (iter = backing_bs(bs); iter != target; iter = backing_bs(iter)) { - /* FIXME Use real permissions */ - block_job_add_bdrv(&s->common, "intermediate node", iter, 0, - BLK_PERM_ALL, &error_abort); + /* XXX BLK_PERM_WRITE needs to be allowed so we don't block + * ourselves at s->base (if writes are blocked for a node, they are + * also blocked for its backing file). The other options would be a + * second filter driver above s->base (== target). */ + ret = block_job_add_bdrv(&s->common, "intermediate node", iter, 0, + BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE, + errp); + if (ret < 0) { + goto fail; + } } } trace_mirror_start(bs, s, opaque); block_job_start(&s->common); + return; + +fail: + if (s) { + g_free(s->replaces); + blk_unref(s->target); + block_job_unref(&s->common); + } + + bdrv_replace_in_backing_chain(mirror_top_bs, backing_bs(mirror_top_bs)); } void mirror_start(const char *job_id, BlockDriverState *bs, 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 void run_block_job(BlockJob *job, Error **errp) { AioContext *aio_context = blk_get_aio_context(job->blk); + /* FIXME In error cases, the job simply goes away and we access a dangling + * pointer below. */ aio_context_acquire(aio_context); do { aio_poll(aio_context, true); @@ -XXX,XX +XXX,XX @@ static int img_commit(int argc, char **argv) const char *filename, *fmt, *cache, *base; BlockBackend *blk; BlockDriverState *bs, *base_bs; + BlockJob *job; bool progress = false, quiet = false, drop = false; bool writethrough; Error *local_err = NULL; @@ -XXX,XX +XXX,XX @@ static int img_commit(int argc, char **argv) bdrv_ref(bs); } - run_block_job(bs->job, &local_err); + job = block_job_get("commit"); + run_block_job(job, &local_err); if (local_err) { goto unref_backing; } diff --git a/tests/qemu-iotests/141 b/tests/qemu-iotests/141 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/141 +++ b/tests/qemu-iotests/141 @@ -XXX,XX +XXX,XX @@ test_blockjob() _send_qemu_cmd $QEMU_HANDLE \ "{'execute': 'x-blockdev-del', 'arguments': {'node-name': 'drv0'}}" \ - 'error' + 'error' | _filter_generated_node_ids _send_qemu_cmd $QEMU_HANDLE \ "{'execute': 'block-job-cancel', diff --git a/tests/qemu-iotests/141.out b/tests/qemu-iotests/141.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/141.out +++ b/tests/qemu-iotests/141.out @@ -XXX,XX +XXX,XX @@ Formatting 'TEST_DIR/o.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/t. Formatting 'TEST_DIR/o.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/t.IMGFMT backing_fmt=IMGFMT {"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "BLOCK_JOB_READY", "data": {"device": "job0", "len": 0, "offset": 0, "speed": 0, "type": "mirror"}} {"return": {}} -{"error": {"class": "GenericError", "desc": "Node drv0 is in use"}} +{"error": {"class": "GenericError", "desc": "Node 'drv0' is busy: node is used as backing hd of 'NODE_NAME'"}} {"return": {}} {"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "BLOCK_JOB_COMPLETED", "data": {"device": "job0", "len": 0, "offset": 0, "speed": 0, "type": "mirror"}} {"return": {}} @@ -XXX,XX +XXX,XX @@ Formatting 'TEST_DIR/o.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/t. {"return": {}} {"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "BLOCK_JOB_READY", "data": {"device": "job0", "len": 0, "offset": 0, "speed": 0, "type": "commit"}} {"return": {}} -{"error": {"class": "GenericError", "desc": "Node drv0 is in use"}} +{"error": {"class": "GenericError", "desc": "Node 'drv0' is busy: node is used as backing hd of 'NODE_NAME'"}} {"return": {}} {"timestamp": {"seconds": TIMESTAMP, "microseconds": TIMESTAMP}, "event": "BLOCK_JOB_COMPLETED", "data": {"device": "job0", "len": 0, "offset": 0, "speed": 0, "type": "commit"}} {"return": {}} -- 1.8.3.1 The correct permissions are relatively obvious here (and explained in code comments). For intermediate streaming, we need to reopen the top node read-write before creating the job now because the permissions system catches attempts to get the BLK_PERM_WRITE_UNCHANGED permission on a read-only node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/stream.c | 39 +++++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 12 deletions(-) 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 void stream_complete(BlockJob *job, void *opaque) /* Reopen the image back in read-only mode if necessary */ if (s->bs_flags != bdrv_get_flags(bs)) { + /* Give up write permissions before making it read-only */ + blk_set_perm(job->blk, 0, BLK_PERM_ALL, &error_abort); bdrv_reopen(bs, s->bs_flags, NULL); } @@ -XXX,XX +XXX,XX @@ void stream_start(const char *job_id, BlockDriverState *bs, BlockDriverState *iter; int orig_bs_flags; - /* FIXME Use real permissions */ - s = block_job_create(job_id, &stream_job_driver, bs, 0, BLK_PERM_ALL, - speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp); - if (!s) { - return; - } - /* Make sure that the image is opened in read-write mode */ orig_bs_flags = bdrv_get_flags(bs); if (!(orig_bs_flags & BDRV_O_RDWR)) { if (bdrv_reopen(bs, orig_bs_flags | BDRV_O_RDWR, errp) != 0) { - block_job_unref(&s->common); return; } } - /* Block all intermediate nodes between bs and base, because they - * will disappear from the chain after this operation */ + /* Prevent concurrent jobs trying to modify the graph structure here, we + * already have our own plans. Also don't allow resize as the image size is + * queried only at the job start and then cached. */ + s = block_job_create(job_id, &stream_job_driver, bs, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | + BLK_PERM_GRAPH_MOD, + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | + BLK_PERM_WRITE, + speed, BLOCK_JOB_DEFAULT, NULL, NULL, errp); + if (!s) { + goto fail; + } + + /* Block all intermediate nodes between bs and base, because they will + * disappear from the chain after this operation. The streaming job reads + * every block only once, assuming that it doesn't change, so block writes + * and resizes. */ for (iter = backing_bs(bs); iter && iter != base; iter = backing_bs(iter)) { - /* FIXME Use real permissions */ block_job_add_bdrv(&s->common, "intermediate node", iter, 0, - BLK_PERM_ALL, &error_abort); + BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED, + &error_abort); } s->base = base; @@ -XXX,XX +XXX,XX @@ void stream_start(const char *job_id, BlockDriverState *bs, s->on_error = on_error; trace_stream_start(bs, base, s); block_job_start(&s->common); + return; + +fail: + if (orig_bs_flags != bdrv_get_flags(bs)) { + bdrv_reopen(bs, s->bs_flags, NULL); + } } -- 1.8.3.1 Management tools need to be able to know about every node in the graph and need a way to address them. Changing the graph structure was okay because libvirt doesn't really manage the node level yet, but future libvirt versions need to deal with both new and old version of qemu. This new option to blockdev-mirror allows the client to set a node-name for the automatically inserted filter driver, and at the same time serves as a witness for a future libvirt that this version of qemu does automatically insert a filter driver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/mirror.c | 14 ++++++++------ blockdev.c | 12 +++++++++++- include/block/block_int.h | 5 ++++- qapi/block-core.json | 8 +++++++- 4 files changed, 30 insertions(+), 9 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, void *opaque, Error **errp, const BlockJobDriver *driver, bool is_none_mode, BlockDriverState *base, - bool auto_complete) + bool auto_complete, const char *filter_node_name) { MirrorBlockJob *s; BlockDriverState *mirror_top_bs; @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, /* In the case of active commit, add dummy driver to provide consistent * reads on the top, while disabling it in the intermediate nodes, and make * the backing chain writable. */ - mirror_top_bs = bdrv_new_open_driver(&bdrv_mirror_top, NULL, BDRV_O_RDWR, - errp); + mirror_top_bs = bdrv_new_open_driver(&bdrv_mirror_top, filter_node_name, + BDRV_O_RDWR, errp); if (mirror_top_bs == NULL) { return; } @@ -XXX,XX +XXX,XX @@ void mirror_start(const char *job_id, BlockDriverState *bs, MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, BlockdevOnError on_source_error, BlockdevOnError on_target_error, - bool unmap, Error **errp) + bool unmap, const char *filter_node_name, Error **errp) { bool is_none_mode; BlockDriverState *base; @@ -XXX,XX +XXX,XX @@ void mirror_start(const char *job_id, BlockDriverState *bs, mirror_start_job(job_id, bs, BLOCK_JOB_DEFAULT, target, replaces, speed, granularity, buf_size, backing_mode, on_source_error, on_target_error, unmap, NULL, NULL, errp, - &mirror_job_driver, is_none_mode, base, false); + &mirror_job_driver, is_none_mode, base, false, + filter_node_name); } void commit_active_start(const char *job_id, BlockDriverState *bs, @@ -XXX,XX +XXX,XX @@ void commit_active_start(const char *job_id, BlockDriverState *bs, mirror_start_job(job_id, bs, creation_flags, base, NULL, speed, 0, 0, MIRROR_LEAVE_BACKING_CHAIN, on_error, on_error, true, cb, opaque, &local_err, - &commit_active_job_driver, false, base, auto_complete); + &commit_active_job_driver, false, base, auto_complete, + NULL); if (local_err) { error_propagate(errp, local_err); goto error_restore_flags; diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs, bool has_on_target_error, BlockdevOnError on_target_error, bool has_unmap, bool unmap, + bool has_filter_node_name, + const char *filter_node_name, Error **errp) { @@ -XXX,XX +XXX,XX @@ static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs, if (!has_unmap) { unmap = true; } + if (!has_filter_node_name) { + filter_node_name = NULL; + } if (granularity != 0 && (granularity < 512 || granularity > 1048576 * 64)) { error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "granularity", @@ -XXX,XX +XXX,XX @@ static void blockdev_mirror_common(const char *job_id, BlockDriverState *bs, mirror_start(job_id, bs, target, has_replaces ? replaces : NULL, speed, granularity, buf_size, sync, backing_mode, - on_source_error, on_target_error, unmap, errp); + on_source_error, on_target_error, unmap, filter_node_name, + errp); } void qmp_drive_mirror(DriveMirror *arg, Error **errp) @@ -XXX,XX +XXX,XX @@ void qmp_drive_mirror(DriveMirror *arg, Error **errp) arg->has_on_source_error, arg->on_source_error, arg->has_on_target_error, arg->on_target_error, arg->has_unmap, arg->unmap, + false, NULL, &local_err); bdrv_unref(target_bs); error_propagate(errp, local_err); @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_mirror(bool has_job_id, const char *job_id, BlockdevOnError on_source_error, bool has_on_target_error, BlockdevOnError on_target_error, + bool has_filter_node_name, + const char *filter_node_name, Error **errp) { BlockDriverState *bs; @@ -XXX,XX +XXX,XX @@ void qmp_blockdev_mirror(bool has_job_id, const char *job_id, has_on_source_error, on_source_error, has_on_target_error, on_target_error, true, true, + has_filter_node_name, filter_node_name, &local_err); error_propagate(errp, local_err); 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 @@ void commit_active_start(const char *job_id, BlockDriverState *bs, * @on_source_error: The action to take upon error reading from the source. * @on_target_error: The action to take upon error writing to the target. * @unmap: Whether to unmap target where source sectors only contain zeroes. + * @filter_node_name: The node name that should be assigned to the filter + * driver that the mirror job inserts into the graph above @bs. NULL means that + * a node name should be autogenerated. * @errp: Error object. * * Start a mirroring operation on @bs. Clusters that are allocated @@ -XXX,XX +XXX,XX @@ void mirror_start(const char *job_id, BlockDriverState *bs, MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, BlockdevOnError on_source_error, BlockdevOnError on_target_error, - bool unmap, Error **errp); + bool unmap, const char *filter_node_name, Error **errp); /* * backup_job_create: 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 @@ # default 'report' (no limitations, since this applies to # a different block device than @device). # +# @filter-node-name: #optional the node name that should be assigned to the +# filter driver that the mirror job inserts into the graph +# above @device. If this option is not given, a node name is +# autogenerated. (Since: 2.9) +# # Returns: nothing on success. # # Since: 2.6 @@ -XXX,XX +XXX,XX @@ 'sync': 'MirrorSyncMode', '*speed': 'int', '*granularity': 'uint32', '*buf-size': 'int', '*on-source-error': 'BlockdevOnError', - '*on-target-error': 'BlockdevOnError' } } + '*on-target-error': 'BlockdevOnError', + '*filter-node-name': 'str' } } ## # @block_set_io_throttle: -- 1.8.3.1 Management tools need to be able to know about every node in the graph and need a way to address them. Changing the graph structure was okay because libvirt doesn't really manage the node level yet, but future libvirt versions need to deal with both new and old version of qemu. This new option to blockdev-commit allows the client to set a node-name for the automatically inserted filter driver, and at the same time serves as a witness for a future libvirt that this version of qemu does automatically insert a filter driver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block/commit.c | 5 +++-- block/mirror.c | 3 ++- block/replication.c | 2 +- blockdev.c | 10 +++++++--- include/block/block_int.h | 13 ++++++++++--- qapi/block-core.json | 8 +++++++- qemu-img.c | 4 ++-- 7 files changed, 32 insertions(+), 13 deletions(-) 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 BlockDriver bdrv_commit_top = { void commit_start(const char *job_id, BlockDriverState *bs, BlockDriverState *base, BlockDriverState *top, int64_t speed, BlockdevOnError on_error, const char *backing_file_str, - Error **errp) + const char *filter_node_name, Error **errp) { CommitBlockJob *s; BlockReopenQueue *reopen_queue = NULL; @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, /* Insert commit_top block node above top, so we can block consistent read * on the backing chain below it */ - commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, NULL, 0, errp); + commit_top_bs = bdrv_new_open_driver(&bdrv_commit_top, filter_node_name, 0, + errp); if (commit_top_bs == NULL) { goto fail; } diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ void mirror_start(const char *job_id, BlockDriverState *bs, void commit_active_start(const char *job_id, BlockDriverState *bs, BlockDriverState *base, int creation_flags, int64_t speed, BlockdevOnError on_error, + const char *filter_node_name, BlockCompletionFunc *cb, void *opaque, Error **errp, bool auto_complete) { @@ -XXX,XX +XXX,XX @@ void commit_active_start(const char *job_id, BlockDriverState *bs, MIRROR_LEAVE_BACKING_CHAIN, on_error, on_error, true, cb, opaque, &local_err, &commit_active_job_driver, false, base, auto_complete, - NULL); + filter_node_name); if (local_err) { error_propagate(errp, local_err); goto error_restore_flags; 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 replication_stop(ReplicationState *rs, bool failover, Error **errp) s->replication_state = BLOCK_REPLICATION_FAILOVER; commit_active_start(NULL, s->active_disk->bs, s->secondary_disk->bs, BLOCK_JOB_INTERNAL, 0, BLOCKDEV_ON_ERROR_REPORT, - replication_done, bs, errp, true); + NULL, replication_done, bs, errp, true); break; default: aio_context_release(aio_context); diff --git a/blockdev.c b/blockdev.c index XXXXXXX..XXXXXXX 100644 --- a/blockdev.c +++ b/blockdev.c @@ -XXX,XX +XXX,XX @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device, bool has_top, const char *top, bool has_backing_file, const char *backing_file, bool has_speed, int64_t speed, + bool has_filter_node_name, const char *filter_node_name, Error **errp) { BlockDriverState *bs; @@ -XXX,XX +XXX,XX @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device, if (!has_speed) { speed = 0; } + if (!has_filter_node_name) { + filter_node_name = NULL; + } /* Important Note: * libvirt relies on the DeviceNotFound error class in order to probe for @@ -XXX,XX +XXX,XX @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device, goto out; } commit_active_start(has_job_id ? job_id : NULL, bs, base_bs, - BLOCK_JOB_DEFAULT, speed, on_error, NULL, NULL, - &local_err, false); + BLOCK_JOB_DEFAULT, speed, on_error, + filter_node_name, NULL, NULL, &local_err, false); } else { BlockDriverState *overlay_bs = bdrv_find_overlay(bs, top_bs); if (bdrv_op_is_blocked(overlay_bs, BLOCK_OP_TYPE_COMMIT_TARGET, errp)) { @@ -XXX,XX +XXX,XX @@ void qmp_block_commit(bool has_job_id, const char *job_id, const char *device, } commit_start(has_job_id ? job_id : NULL, bs, base_bs, top_bs, speed, on_error, has_backing_file ? backing_file : NULL, - &local_err); + filter_node_name, &local_err); } if (local_err != NULL) { error_propagate(errp, local_err); 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 @@ void stream_start(const char *job_id, BlockDriverState *bs, * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @on_error: The action to take upon error. * @backing_file_str: String to use as the backing file in @top's overlay + * @filter_node_name: The node name that should be assigned to the filter + * driver that the commit job inserts into the graph above @top. NULL means + * that a node name should be autogenerated. * @errp: Error object. * */ void commit_start(const char *job_id, BlockDriverState *bs, BlockDriverState *base, BlockDriverState *top, int64_t speed, BlockdevOnError on_error, const char *backing_file_str, - Error **errp); + const char *filter_node_name, Error **errp); /** * commit_active_start: * @job_id: The id of the newly-created job, or %NULL to use the @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, * See @BlockJobCreateFlags * @speed: The maximum speed, in bytes per second, or 0 for unlimited. * @on_error: The action to take upon error. + * @filter_node_name: The node name that should be assigned to the filter + * driver that the commit job inserts into the graph above @bs. NULL means that + * a node name should be autogenerated. * @cb: Completion function for the job. * @opaque: Opaque pointer value passed to @cb. * @errp: Error object. @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, void commit_active_start(const char *job_id, BlockDriverState *bs, BlockDriverState *base, int creation_flags, int64_t speed, BlockdevOnError on_error, - BlockCompletionFunc *cb, - void *opaque, Error **errp, bool auto_complete); + const char *filter_node_name, + BlockCompletionFunc *cb, void *opaque, Error **errp, + bool auto_complete); /* * mirror_start: * @job_id: The id of the newly-created job, or %NULL to use the 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 @@ # # @speed: #optional the maximum speed, in bytes per second # +# @filter-node-name: #optional the node name that should be assigned to the +# filter driver that the commit job inserts into the graph +# above @top. If this option is not given, a node name is +# autogenerated. (Since: 2.9) +# # Returns: Nothing on success # If commit or stream is already active on this device, DeviceInUse # If @device does not exist, DeviceNotFound @@ -XXX,XX +XXX,XX @@ ## { 'command': 'block-commit', 'data': { '*job-id': 'str', 'device': 'str', '*base': 'str', '*top': 'str', - '*backing-file': 'str', '*speed': 'int' } } + '*backing-file': 'str', '*speed': 'int', + '*filter-node-name': 'str' } } ## # @drive-backup: 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 img_commit(int argc, char **argv) aio_context = bdrv_get_aio_context(bs); aio_context_acquire(aio_context); commit_active_start("commit", bs, base_bs, BLOCK_JOB_DEFAULT, 0, - BLOCKDEV_ON_ERROR_REPORT, common_block_job_cb, &cbi, - &local_err, false); + BLOCKDEV_ON_ERROR_REPORT, NULL, common_block_job_cb, + &cbi, &local_err, false); aio_context_release(aio_context); if (local_err) { goto done; -- 1.8.3.1 The HMP command 'qemu-io' is a bit tricky because it wants to work on the original BlockBackend, but additional permissions could be required. The details are explained in a comment in the code, but in summary, just request whatever permissions the current qemu-io command needs. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block/block-backend.c | 6 ++++++ hmp.c | 26 +++++++++++++++++++++++++- include/qemu-io.h | 1 + include/sysemu/block-backend.h | 1 + qemu-io-cmds.c | 28 ++++++++++++++++++++++++++++ 5 files changed, 61 insertions(+), 1 deletion(-) 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 blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, return 0; } +void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t *shared_perm) +{ + *perm = blk->perm; + *shared_perm = blk->shared_perm; +} + static int blk_do_attach_dev(BlockBackend *blk, void *dev) { if (blk->dev) { diff --git a/hmp.c b/hmp.c index XXXXXXX..XXXXXXX 100644 --- a/hmp.c +++ b/hmp.c @@ -XXX,XX +XXX,XX @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict) if (!blk) { BlockDriverState *bs = bdrv_lookup_bs(NULL, device, &err); if (bs) { - /* FIXME Use real permissions */ blk = local_blk = blk_new(0, BLK_PERM_ALL); ret = blk_insert_bs(blk, bs, &err); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict) aio_context = blk_get_aio_context(blk); aio_context_acquire(aio_context); + /* + * Notably absent: Proper permission management. This is sad, but it seems + * almost impossible to achieve without changing the semantics and thereby + * limiting the use cases of the qemu-io HMP command. + * + * In an ideal world we would unconditionally create a new BlockBackend for + * qemuio_command(), but we have commands like 'reopen' and want them to + * take effect on the exact BlockBackend whose name the user passed instead + * of just on a temporary copy of it. + * + * Another problem is that deleting the temporary BlockBackend involves + * draining all requests on it first, but some qemu-iotests cases want to + * issue multiple aio_read/write requests and expect them to complete in + * the background while the monitor has already returned. + * + * This is also what prevents us from saving the original permissions and + * restoring them later: We can't revoke permissions until all requests + * have completed, and we don't know when that is nor can we really let + * anything else run before we have revoken them to avoid race conditions. + * + * What happens now is that command() in qemu-io-cmds.c can extend the + * permissions if necessary for the qemu-io command. And they simply stay + * extended, possibly resulting in a read-only guest device keeping write + * permissions. Ugly, but it appears to be the lesser evil. + */ qemuio_command(blk, command); aio_context_release(aio_context); diff --git a/include/qemu-io.h b/include/qemu-io.h index XXXXXXX..XXXXXXX 100644 --- a/include/qemu-io.h +++ b/include/qemu-io.h @@ -XXX,XX +XXX,XX @@ typedef struct cmdinfo { const char *args; const char *oneline; helpfunc_t help; + uint64_t perm; } cmdinfo_t; extern bool qemuio_misalign; 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 @@ bool bdrv_has_blk(BlockDriverState *bs); bool bdrv_is_root_node(BlockDriverState *bs); int blk_set_perm(BlockBackend *blk, uint64_t perm, uint64_t shared_perm, Error **errp); +void blk_get_perm(BlockBackend *blk, uint64_t *perm, uint64_t *shared_perm); void blk_set_allow_write_beyond_eof(BlockBackend *blk, bool allow); void blk_iostatus_enable(BlockBackend *blk); 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 command(BlockBackend *blk, const cmdinfo_t *ct, int argc, } return 0; } + + /* Request additional permissions if necessary for this command. The caller + * is responsible for restoring the original permissions afterwards if this + * is what it wants. */ + if (ct->perm && blk_is_available(blk)) { + uint64_t orig_perm, orig_shared_perm; + blk_get_perm(blk, &orig_perm, &orig_shared_perm); + + if (ct->perm & ~orig_perm) { + uint64_t new_perm; + Error *local_err = NULL; + int ret; + + new_perm = orig_perm | ct->perm; + + ret = blk_set_perm(blk, new_perm, orig_shared_perm, &local_err); + if (ret < 0) { + error_report_err(local_err); + return 0; + } + } + } + optind = 0; return ct->cfunc(blk, argc, argv); } @@ -XXX,XX +XXX,XX @@ static const cmdinfo_t write_cmd = { .name = "write", .altname = "w", .cfunc = write_f, + .perm = BLK_PERM_WRITE, .argmin = 2, .argmax = -1, .args = "[-bcCfquz] [-P pattern] off len", @@ -XXX,XX +XXX,XX @@ static int writev_f(BlockBackend *blk, int argc, char **argv); static const cmdinfo_t writev_cmd = { .name = "writev", .cfunc = writev_f, + .perm = BLK_PERM_WRITE, .argmin = 2, .argmax = -1, .args = "[-Cfq] [-P pattern] off len [len..]", @@ -XXX,XX +XXX,XX @@ static int aio_write_f(BlockBackend *blk, int argc, char **argv); static const cmdinfo_t aio_write_cmd = { .name = "aio_write", .cfunc = aio_write_f, + .perm = BLK_PERM_WRITE, .argmin = 2, .argmax = -1, .args = "[-Cfiquz] [-P pattern] off len [len..]", @@ -XXX,XX +XXX,XX @@ static const cmdinfo_t truncate_cmd = { .name = "truncate", .altname = "t", .cfunc = truncate_f, + .perm = BLK_PERM_WRITE | BLK_PERM_RESIZE, .argmin = 1, .argmax = 1, .args = "off", @@ -XXX,XX +XXX,XX @@ static const cmdinfo_t discard_cmd = { .name = "discard", .altname = "d", .cfunc = discard_f, + .perm = BLK_PERM_WRITE, .argmin = 2, .argmax = -1, .args = "[-Cq] off len", -- 1.8.3.1 Request BLK_PERM_CONSISTENT_READ for the source of block migration, and handle potential permission errors as good as we can in this place (which is not very good, but it matches the other failure cases). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- migration/block.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/migration/block.c b/migration/block.c index XXXXXXX..XXXXXXX 100644 --- a/migration/block.c +++ b/migration/block.c @@ -XXX,XX +XXX,XX @@ static void unset_dirty_tracking(void) } } -static void init_blk_migration(QEMUFile *f) +static int init_blk_migration(QEMUFile *f) { BlockDriverState *bs; BlkMigDevState *bmds; @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) BlkMigDevState *bmds; BlockDriverState *bs; } *bmds_bs; + Error *local_err = NULL; + int ret; block_mig_state.submitted = 0; block_mig_state.read_done = 0; @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) sectors = bdrv_nb_sectors(bs); if (sectors <= 0) { + ret = sectors; goto out; } bmds = g_new0(BlkMigDevState, 1); - /* FIXME Use real permissions */ - bmds->blk = blk_new(0, BLK_PERM_ALL); + bmds->blk = blk_new(BLK_PERM_CONSISTENT_READ, BLK_PERM_ALL); bmds->blk_name = g_strdup(bdrv_get_device_name(bs)); bmds->bulk_completed = 0; bmds->total_sectors = sectors; @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) BlockDriverState *bs = bmds_bs[i].bs; if (bmds) { - blk_insert_bs(bmds->blk, bs, &error_abort); + ret = blk_insert_bs(bmds->blk, bs, &local_err); + if (ret < 0) { + error_report_err(local_err); + goto out; + } alloc_aio_bitmap(bmds); error_setg(&bmds->blocker, "block device is in use by migration"); @@ -XXX,XX +XXX,XX @@ static void init_blk_migration(QEMUFile *f) } } + ret = 0; out: g_free(bmds_bs); + return ret; } /* Called with no lock taken. */ @@ -XXX,XX +XXX,XX @@ static int block_save_setup(QEMUFile *f, void *opaque) block_mig_state.submitted, block_mig_state.transferred); qemu_mutex_lock_iothread(); - init_blk_migration(f); + ret = init_blk_migration(f); + if (ret < 0) { + qemu_mutex_unlock_iothread(); + return ret; + } /* start track dirty blocks */ ret = set_dirty_tracking(); -- 1.8.3.1 NBD can't cope with device size changes, so resize must be forbidden, but otherwise we can tolerate anything. Depending on whether the export is writable or not, we only require consistent reads and writes. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- nbd/server.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 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 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, off_t size, { BlockBackend *blk; NBDExport *exp = g_malloc0(sizeof(NBDExport)); + uint64_t perm; int ret; - /* FIXME Use real permissions */ - blk = blk_new(0, BLK_PERM_ALL); + /* Don't allow resize while the NBD server is running, otherwise we don't + * care what happens with the node. */ + perm = BLK_PERM_CONSISTENT_READ; + if ((nbdflags & NBD_FLAG_READ_ONLY) == 0) { + perm |= BLK_PERM_WRITE; + } + blk = blk_new(perm, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED | + BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD); ret = blk_insert_bs(blk, bs, errp); if (ret < 0) { goto fail; -- 1.8.3.1 Not requesting any permissions is actually correct for these test cases because no actual I/O or other operation covered by the permission system is performed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- tests/test-blockjob.c | 2 +- tests/test-throttle.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/test-blockjob.c b/tests/test-blockjob.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-blockjob.c +++ b/tests/test-blockjob.c @@ -XXX,XX +XXX,XX @@ static BlockJob *do_test_id(BlockBackend *blk, const char *id, * BlockDriverState inserted. */ static BlockBackend *create_blk(const char *name) { - /* FIXME Use real permissions */ + /* No I/O is performed on this device */ BlockBackend *blk = blk_new(0, BLK_PERM_ALL); BlockDriverState *bs; diff --git a/tests/test-throttle.c b/tests/test-throttle.c index XXXXXXX..XXXXXXX 100644 --- a/tests/test-throttle.c +++ b/tests/test-throttle.c @@ -XXX,XX +XXX,XX @@ static void test_groups(void) BlockBackend *blk1, *blk2, *blk3; BlockBackendPublic *blkp1, *blkp2, *blkp3; - /* FIXME Use real permissions */ + /* No actual I/O is performed on these devices */ blk1 = blk_new(0, BLK_PERM_ALL); blk2 = blk_new(0, BLK_PERM_ALL); blk3 = blk_new(0, BLK_PERM_ALL); -- 1.8.3.1 This is where we want to check the permissions, so we need to have the BdrvChild around where they are stored. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block/io.c | 37 +++++++++++++++++++++---------------- 1 file changed, 21 insertions(+), 16 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 @@ bdrv_driver_pwritev_compressed(BlockDriverState *bs, uint64_t offset, return drv->bdrv_co_pwritev_compressed(bs, offset, bytes, qiov); } -static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs, +static int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, int64_t offset, unsigned int bytes, QEMUIOVector *qiov) { + BlockDriverState *bs = child->bs; + /* Perform I/O through a temporary buffer so that users who scribble over * their read buffer while the operation is in progress do not end up * modifying the image file. This is critical for zero-copy guest I/O @@ -XXX,XX +XXX,XX @@ err: * handles copy on read, zeroing after EOF, and fragmentation of large * reads; any other features must be implemented by the caller. */ -static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, +static int coroutine_fn bdrv_aligned_preadv(BdrvChild *child, BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, int64_t align, QEMUIOVector *qiov, int flags) { + BlockDriverState *bs = child->bs; int64_t total_bytes, max_bytes; int ret = 0; uint64_t bytes_remaining = bytes; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs, } if (!ret || pnum != nb_sectors) { - ret = bdrv_co_do_copy_on_readv(bs, offset, bytes, qiov); + ret = bdrv_co_do_copy_on_readv(child, offset, bytes, qiov); goto out; } } @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_preadv(BdrvChild *child, } tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_READ); - ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align, + ret = bdrv_aligned_preadv(child, &req, offset, bytes, align, use_local_qiov ? &local_qiov : qiov, flags); tracked_request_end(&req); @@ -XXX,XX +XXX,XX @@ fail: * Forwards an already correctly aligned write request to the BlockDriver, * after possibly fragmenting it. */ -static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, +static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child, BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, int64_t align, QEMUIOVector *qiov, int flags) { + BlockDriverState *bs = child->bs; BlockDriver *drv = bs->drv; bool waited; int ret; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, return ret; } -static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, +static int coroutine_fn bdrv_co_do_zero_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes, BdrvRequestFlags flags, BdrvTrackedRequest *req) { + BlockDriverState *bs = child->bs; uint8_t *buf = NULL; QEMUIOVector local_qiov; struct iovec iov; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, mark_request_serialising(req, align); wait_serialising_requests(req); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); - ret = bdrv_aligned_preadv(bs, req, offset & ~(align - 1), align, + ret = bdrv_aligned_preadv(child, req, offset & ~(align - 1), align, align, &local_qiov, 0); if (ret < 0) { goto fail; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_HEAD); memset(buf + head_padding_bytes, 0, zero_bytes); - ret = bdrv_aligned_pwritev(bs, req, offset & ~(align - 1), align, + ret = bdrv_aligned_pwritev(child, req, offset & ~(align - 1), align, align, &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, if (bytes >= align) { /* Write the aligned part in the middle. */ uint64_t aligned_bytes = bytes & ~(align - 1); - ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, align, + ret = bdrv_aligned_pwritev(child, req, offset, aligned_bytes, align, NULL, flags); if (ret < 0) { goto fail; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, mark_request_serialising(req, align); wait_serialising_requests(req); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); - ret = bdrv_aligned_preadv(bs, req, offset, align, + ret = bdrv_aligned_preadv(child, req, offset, align, align, &local_qiov, 0); if (ret < 0) { goto fail; @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); memset(buf, 0, bytes); - ret = bdrv_aligned_pwritev(bs, req, offset, align, align, + ret = bdrv_aligned_pwritev(child, req, offset, align, align, &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); } fail: @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_WRITE); if (!qiov) { - ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req); + ret = bdrv_co_do_zero_pwritev(child, offset, bytes, flags, &req); goto out; } @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, qemu_iovec_init_external(&head_qiov, &head_iov, 1); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_HEAD); - ret = bdrv_aligned_preadv(bs, &req, offset & ~(align - 1), align, + ret = bdrv_aligned_preadv(child, &req, offset & ~(align - 1), align, align, &head_qiov, 0); if (ret < 0) { goto fail; @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, qemu_iovec_init_external(&tail_qiov, &tail_iov, 1); bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_TAIL); - ret = bdrv_aligned_preadv(bs, &req, (offset + bytes) & ~(align - 1), align, - align, &tail_qiov, 0); + ret = bdrv_aligned_preadv(child, &req, (offset + bytes) & ~(align - 1), + align, align, &tail_qiov, 0); if (ret < 0) { goto fail; } @@ -XXX,XX +XXX,XX @@ int coroutine_fn bdrv_co_pwritev(BdrvChild *child, bytes = ROUND_UP(bytes, align); } - ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, align, + ret = bdrv_aligned_pwritev(child, &req, offset, bytes, align, use_local_qiov ? &local_qiov : qiov, flags); -- 1.8.3.1 This adds assertions that ensure that the necessary write permissions have been granted before someone attempts to write to a node. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block/io.c | 3 +++ 1 file changed, 3 insertions(+) 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 int coroutine_fn bdrv_co_do_copy_on_readv(BdrvChild *child, size_t skip_bytes; int ret; + assert(child->perm & (BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE)); + /* Cover entire cluster so no additional backing file I/O is required when * allocating cluster in the image file. */ @@ -XXX,XX +XXX,XX @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child, assert(!waited || !req->serialising); assert(req->overlap_offset <= offset); assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); + assert(child->perm & BLK_PERM_WRITE); ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req); -- 1.8.3.1 This adds an assertion that ensures that the necessary resize permission has been granted before bdrv_truncate() is called. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> --- block.c | 3 +++ block/io.c | 1 + 2 files changed, 4 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_truncate(BdrvChild *child, int64_t offset) BlockDriverState *bs = child->bs; BlockDriver *drv = bs->drv; int ret; + + assert(child->perm & BLK_PERM_RESIZE); + if (!drv) return -ENOMEDIUM; if (!drv->bdrv_truncate) 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 int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child, assert(req->overlap_offset <= offset); assert(offset + bytes <= req->overlap_offset + req->overlap_bytes); assert(child->perm & BLK_PERM_WRITE); + assert(end_sector <= bs->total_sectors || child->perm & BLK_PERM_RESIZE); ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req); -- 1.8.3.1 Not all callers of bdrv_set_backing_hd() know for sure that attaching the backing file will be allowed by the permission system. Return the error from the function rather than aborting. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 30 +++++++++++++++++++++++------- block/commit.c | 14 +++++++------- block/mirror.c | 7 ++++++- block/stream.c | 9 ++++++++- block/vvfat.c | 2 +- include/block/block.h | 3 ++- 6 files changed, 47 insertions(+), 18 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_parent_cb_resize(BlockDriverState *bs) * Sets the backing file link of a BDS. A new reference is created; callers * which don't need their own reference any more must call bdrv_unref(). */ -void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) +void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, + Error **errp) { if (backing_hd) { bdrv_ref(backing_hd); @@ -XXX,XX +XXX,XX @@ void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd) bs->backing = NULL; goto out; } - /* FIXME Error handling */ + bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_backing, - &error_abort); + errp); + if (!bs->backing) { + bdrv_unref(backing_hd); + } out: bdrv_refresh_limits(bs, NULL); @@ -XXX,XX +XXX,XX @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, /* Hook up the backing file link; drop our reference, bs owns the * backing_hd reference now */ - bdrv_set_backing_hd(bs, backing_hd); + bdrv_set_backing_hd(bs, backing_hd, &local_err); bdrv_unref(backing_hd); + if (local_err) { + ret = -EINVAL; + goto free_exit; + } qdict_del(parent_options, bdref_key); @@ -XXX,XX +XXX,XX @@ static void bdrv_close(BlockDriverState *bs) bs->drv->bdrv_close(bs); bs->drv = NULL; - bdrv_set_backing_hd(bs, NULL); + bdrv_set_backing_hd(bs, NULL, &error_abort); if (bs->file != NULL) { bdrv_unref_child(bs, bs->file); @@ -XXX,XX +XXX,XX @@ void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) bdrv_ref(bs_top); change_parent_backing_link(bs_top, bs_new); - bdrv_set_backing_hd(bs_new, bs_top); + /* FIXME Error handling */ + bdrv_set_backing_hd(bs_new, bs_top, &error_abort); bdrv_unref(bs_top); /* bs_new is now referenced by its new parents, we don't need the @@ -XXX,XX +XXX,XX @@ int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top, BlockDriverState *base, const char *backing_file_str) { BlockDriverState *new_top_bs = NULL; + Error *local_err = NULL; int ret = -EIO; if (!top->drv || !base->drv) { @@ -XXX,XX +XXX,XX @@ int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top, if (ret) { goto exit; } - bdrv_set_backing_hd(new_top_bs, base); + + bdrv_set_backing_hd(new_top_bs, base, &local_err); + if (local_err) { + ret = -EPERM; + error_report_err(local_err); + goto exit; + } ret = 0; exit: 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 void commit_complete(BlockJob *job, void *opaque) * filter driver from the backing chain. Do this as the final step so that * the 'consistent read' permission can be granted. */ if (remove_commit_top_bs) { - bdrv_set_backing_hd(overlay_bs, top); + bdrv_set_backing_hd(overlay_bs, top, &error_abort); } } @@ -XXX,XX +XXX,XX @@ void commit_start(const char *job_id, BlockDriverState *bs, goto fail; } - bdrv_set_backing_hd(commit_top_bs, top); - bdrv_set_backing_hd(overlay_bs, commit_top_bs); + bdrv_set_backing_hd(commit_top_bs, top, &error_abort); + bdrv_set_backing_hd(overlay_bs, commit_top_bs, &error_abort); s->commit_top_bs = commit_top_bs; bdrv_unref(commit_top_bs); @@ -XXX,XX +XXX,XX @@ fail: blk_unref(s->top); } if (commit_top_bs) { - bdrv_set_backing_hd(overlay_bs, top); + bdrv_set_backing_hd(overlay_bs, top, &error_abort); } block_job_unref(&s->common); } @@ -XXX,XX +XXX,XX @@ int bdrv_commit(BlockDriverState *bs) goto ro_cleanup; } - bdrv_set_backing_hd(commit_top_bs, backing_file_bs); - bdrv_set_backing_hd(bs, commit_top_bs); + bdrv_set_backing_hd(commit_top_bs, backing_file_bs, &error_abort); + bdrv_set_backing_hd(bs, commit_top_bs, &error_abort); ret = blk_insert_bs(backing, backing_file_bs, &local_err); if (ret < 0) { @@ -XXX,XX +XXX,XX @@ ro_cleanup: blk_unref(backing); if (backing_file_bs) { - bdrv_set_backing_hd(bs, backing_file_bs); + bdrv_set_backing_hd(bs, backing_file_bs, &error_abort); } bdrv_unref(commit_top_bs); blk_unref(src); diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) BlockDriverState *src = s->source; BlockDriverState *target_bs = blk_bs(s->target); BlockDriverState *mirror_top_bs = s->mirror_top_bs; + Error *local_err = NULL; /* Make sure that the source BDS doesn't go away before we called * block_job_completed(). */ @@ -XXX,XX +XXX,XX @@ static void mirror_exit(BlockJob *job, void *opaque) if (s->backing_mode == MIRROR_SOURCE_BACKING_CHAIN) { BlockDriverState *backing = s->is_none_mode ? src : s->base; if (backing_bs(target_bs) != backing) { - bdrv_set_backing_hd(target_bs, backing); + bdrv_set_backing_hd(target_bs, backing, &local_err); + if (local_err) { + error_report_err(local_err); + data->ret = -EPERM; + } } } 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 void stream_complete(BlockJob *job, void *opaque) StreamCompleteData *data = opaque; BlockDriverState *bs = blk_bs(job->blk); BlockDriverState *base = s->base; + Error *local_err = NULL; if (!block_job_is_cancelled(&s->common) && data->reached_end && data->ret == 0) { @@ -XXX,XX +XXX,XX @@ static void stream_complete(BlockJob *job, void *opaque) } } data->ret = bdrv_change_backing_file(bs, base_id, base_fmt); - bdrv_set_backing_hd(bs, base); + bdrv_set_backing_hd(bs, base, &local_err); + if (local_err) { + error_report_err(local_err); + data->ret = -EPERM; + goto out; + } } +out: /* Reopen the image back in read-only mode if necessary */ if (s->bs_flags != bdrv_get_flags(bs)) { /* Give up write permissions before making it read-only */ 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 enable_write_target(BlockDriverState *bs, Error **errp) &error_abort); *(void**) backing->opaque = s; - bdrv_set_backing_hd(s->bs, backing); + bdrv_set_backing_hd(s->bs, backing, &error_abort); bdrv_unref(backing); return 0; 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 @@ BdrvChild *bdrv_open_child(const char *filename, BlockDriverState* parent, const BdrvChildRole *child_role, bool allow_none, Error **errp); -void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd); +void bdrv_set_backing_hd(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, -- 1.8.3.1 Aborting on error in bdrv_append() isn't correct. This patch fixes it and lets the callers handle failures. Test case 085 needs a reference output update. This is caused by the reversed order of bdrv_set_backing_hd() and change_parent_backing_link() in bdrv_append(): When the backing file of the new node is set, the parent nodes are still pointing to the old top, so the backing blocker is now initialised with the node name rather than the BlockBackend name. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> --- block.c | 23 +++++++++++++++++------ block/mirror.c | 9 ++++++++- blockdev.c | 18 +++++++++++++++--- include/block/block.h | 3 ++- tests/qemu-iotests/085.out | 2 +- 5 files changed, 43 insertions(+), 12 deletions(-) diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, int64_t total_size; QemuOpts *opts = NULL; BlockDriverState *bs_snapshot; + Error *local_err = NULL; int ret; /* if snapshot, we create a temporary backing file and open it @@ -XXX,XX +XXX,XX @@ static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, * call bdrv_unref() on it), so in order to be able to return one, we have * to increase bs_snapshot's refcount here */ bdrv_ref(bs_snapshot); - bdrv_append(bs_snapshot, bs); + bdrv_append(bs_snapshot, bs, &local_err); + if (local_err) { + error_propagate(errp, local_err); + ret = -EINVAL; + goto out; + } g_free(tmp_filename); return bs_snapshot; @@ -XXX,XX +XXX,XX @@ static void change_parent_backing_link(BlockDriverState *from, * parents of bs_top after bdrv_append() returns. If the caller needs to keep a * reference of its own, it must call bdrv_ref(). */ -void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top) +void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, + Error **errp) { + Error *local_err = NULL; + assert(!atomic_read(&bs_top->in_flight)); assert(!atomic_read(&bs_new->in_flight)); - bdrv_ref(bs_top); + bdrv_set_backing_hd(bs_new, bs_top, &local_err); + if (local_err) { + error_propagate(errp, local_err); + goto out; + } change_parent_backing_link(bs_top, bs_new); - /* FIXME Error handling */ - bdrv_set_backing_hd(bs_new, bs_top, &error_abort); - bdrv_unref(bs_top); /* bs_new is now referenced by its new parents, we don't need the * additional reference any more. */ +out: bdrv_unref(bs_new); } diff --git a/block/mirror.c b/block/mirror.c index XXXXXXX..XXXXXXX 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, BlockDriverState *mirror_top_bs; bool target_graph_mod; bool target_is_backing; + Error *local_err = NULL; int ret; if (granularity == 0) { @@ -XXX,XX +XXX,XX @@ static void mirror_start_job(const char *job_id, BlockDriverState *bs, * it alive until block_job_create() even if bs has no parent. */ bdrv_ref(mirror_top_bs); bdrv_drained_begin(bs); - bdrv_append(mirror_top_bs, bs); + bdrv_append(mirror_top_bs, bs, &local_err); bdrv_drained_end(bs); + if (local_err) { + bdrv_unref(mirror_top_bs); + error_propagate(errp, local_err); + return; + } + /* Make sure that the source is not resized while the job is running */ s = block_job_create(job_id, driver, mirror_top_bs, BLK_PERM_CONSISTENT_READ, 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, if (!state->new_bs->drv->supports_backing) { error_setg(errp, "The snapshot does not support backing images"); + return; + } + + /* This removes our old bs and adds the new bs. This is an operation that + * can fail, so we need to do it in .prepare; undoing it for abort is + * always possible. */ + bdrv_ref(state->new_bs); + bdrv_append(state->new_bs, state->old_bs, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; } } @@ -XXX,XX +XXX,XX @@ static void external_snapshot_commit(BlkActionState *common) bdrv_set_aio_context(state->new_bs, state->aio_context); - /* This removes our old bs and adds the new bs */ - bdrv_append(state->new_bs, state->old_bs); /* We don't need (or want) to use the transactional * bdrv_reopen_multiple() across all the entries at once, because we * don't want to abort all of them if one of them fails the reopen */ @@ -XXX,XX +XXX,XX @@ static void external_snapshot_abort(BlkActionState *common) ExternalSnapshotState *state = DO_UPCAST(ExternalSnapshotState, common, common); if (state->new_bs) { - bdrv_unref(state->new_bs); + if (state->new_bs->backing) { + bdrv_replace_in_backing_chain(state->new_bs, state->old_bs); + } } } @@ -XXX,XX +XXX,XX @@ static void external_snapshot_clean(BlkActionState *common) if (state->aio_context) { bdrv_drained_end(state->old_bs); aio_context_release(state->aio_context); + bdrv_unref(state->new_bs); } } 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_create(BlockDriver *drv, const char* filename, QemuOpts *opts, Error **errp); int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); BlockDriverState *bdrv_new(void); -void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top); +void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, + Error **errp); void bdrv_replace_in_backing_chain(BlockDriverState *old, BlockDriverState *new); diff --git a/tests/qemu-iotests/085.out b/tests/qemu-iotests/085.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/085.out +++ b/tests/qemu-iotests/085.out @@ -XXX,XX +XXX,XX @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 backing_file=TEST_DIR/ === Invalid command - snapshot node used as backing hd === -{"error": {"class": "GenericError", "desc": "Node 'snap_11' is busy: node is used as backing hd of 'virtio0'"}} +{"error": {"class": "GenericError", "desc": "Node 'snap_11' is busy: node is used as backing hd of 'snap_12'"}} === Invalid command - snapshot node has a backing image === -- 1.8.3.1 The following changes since commit 1b8c45899715d292398152ba97ef755ccaf84680: Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20200507a' into staging (2020-05-07 18:43:20 +0100) are available in the Git repository at: git://repo.or.cz/qemu/kevin.git tags/for-upstream for you to fetch changes up to 47e0b38a13935cb666f88964c3096654092f42d6: block: Drop unused .bdrv_has_zero_init_truncate (2020-05-08 13:26:35 +0200) ---------------------------------------------------------------- Block layer patches: - qcow2: Fix preallocation on block devices - backup: Make sure that source and target size match - vmdk: Fix zero cluster handling - Follow-up cleanups and fixes for the truncate changes - iotests: Skip more tests if required drivers are missing ---------------------------------------------------------------- Alberto Garcia (1): qcow2: Avoid integer wraparound in qcow2_co_truncate() Eric Blake (9): gluster: Drop useless has_zero_init callback file-win32: Support BDRV_REQ_ZERO_WRITE for truncate nfs: Support BDRV_REQ_ZERO_WRITE for truncate rbd: Support BDRV_REQ_ZERO_WRITE for truncate sheepdog: Support BDRV_REQ_ZERO_WRITE for truncate ssh: Support BDRV_REQ_ZERO_WRITE for truncate parallels: Rework truncation logic vhdx: Rework truncation logic block: Drop unused .bdrv_has_zero_init_truncate Kevin Wolf (11): vmdk: Rename VmdkMetaData.valid to new_allocation vmdk: Fix zero cluster allocation vmdk: Fix partial overwrite of zero cluster vmdk: Don't update L2 table for zero write on zero cluster vmdk: Flush only once in vmdk_L2update() iotests: vmdk: Enable zeroed_grained=on by default iotests/283: Use consistent size for source and target backup: Improve error for bdrv_getlength() failure backup: Make sure that source and target size match iotests: Backup with different source/target size iotests/055: Use cache.no-flush for vmdk target Max Reitz (1): qcow2: Fix preallocation on block devices Vladimir Sementsov-Ogievskiy (8): iotests: handle tmpfs iotests/082: require bochs iotests/148: use skip_if_unsupported iotests/041: drop self.assert_no_active_block_jobs() iotests/055: refactor compressed backup to vmdk iotests/055: skip vmdk target tests if vmdk is not whitelisted iotests/109: mark required formats as required to support whitelisting iotests/113: mark bochs as required to support whitelisting include/block/block.h | 1 - include/block/block_int.h | 7 --- block.c | 21 -------- block/backup-top.c | 14 +++-- block/backup.c | 18 +++++-- block/file-posix.c | 1 - block/file-win32.c | 4 +- block/gluster.c | 14 ----- block/nfs.c | 4 +- block/parallels.c | 25 +++++---- block/qcow2.c | 23 ++++++--- block/qed.c | 1 - block/raw-format.c | 6 --- block/rbd.c | 4 +- block/sheepdog.c | 4 +- block/ssh.c | 5 +- block/vhdx.c | 89 ++++++++++++++++++-------------- block/vmdk.c | 47 ++++++++++------- tests/qemu-iotests/041 | 8 --- tests/qemu-iotests/055 | 120 ++++++++++++++++++++++++++++++------------- tests/qemu-iotests/055.out | 4 +- tests/qemu-iotests/059 | 6 +-- tests/qemu-iotests/082 | 1 + tests/qemu-iotests/091 | 2 +- tests/qemu-iotests/109 | 1 + tests/qemu-iotests/113 | 4 +- tests/qemu-iotests/148 | 1 + tests/qemu-iotests/283 | 6 ++- tests/qemu-iotests/283.out | 2 +- tests/qemu-iotests/292 | 73 ++++++++++++++++++++++++++ tests/qemu-iotests/292.out | 24 +++++++++ tests/qemu-iotests/check | 3 ++ tests/qemu-iotests/common.rc | 37 ++++++++++++- tests/qemu-iotests/group | 1 + 34 files changed, 386 insertions(+), 195 deletions(-) create mode 100755 tests/qemu-iotests/292 create mode 100644 tests/qemu-iotests/292.out From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Some tests requires O_DIRECT, or want it by default. Introduce smarter O_DIRECT handling: - Check O_DIRECT in common.rc, if it is requested by selected cache-mode. - Support second fall-through argument in _default_cache_mode Inspired-by: Max's 23e1d054112cec1e Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-2-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/091 | 2 +- tests/qemu-iotests/common.rc | 37 ++++++++++++++++++++++++++++++++++-- 2 files changed, 36 insertions(+), 3 deletions(-) diff --git a/tests/qemu-iotests/091 b/tests/qemu-iotests/091 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/091 +++ b/tests/qemu-iotests/091 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 _supported_fmt qcow2 _supported_proto file _supported_os Linux -_default_cache_mode none _supported_cache_modes writethrough none writeback +_default_cache_mode none writeback size=1G diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/common.rc +++ b/tests/qemu-iotests/common.rc @@ -XXX,XX +XXX,XX @@ _supported_cache_modes() _notrun "not suitable for cache mode: $CACHEMODE" } +# Check whether the filesystem supports O_DIRECT +_check_o_direct() +{ + $QEMU_IMG create -f raw "$TEST_IMG".test_o_direct 1M > /dev/null + out=$($QEMU_IO -f raw -t none -c quit "$TEST_IMG".test_o_direct 2>&1) + rm -f "$TEST_IMG".test_o_direct + + [[ "$out" != *"O_DIRECT"* ]] +} + +_require_o_direct() +{ + if ! _check_o_direct; then + _notrun "file system on $TEST_DIR does not support O_DIRECT" + fi +} + +_check_cache_mode() +{ + if [ $CACHEMODE == "none" ] || [ $CACHEMODE == "directsync" ]; then + _require_o_direct + fi +} + +_check_cache_mode + +# $1 - cache mode to use by default +# $2 - (optional) cache mode to use by default if O_DIRECT is not supported _default_cache_mode() { if $CACHEMODE_IS_DEFAULT; then - CACHEMODE="$1" - QEMU_IO="$QEMU_IO --cache $1" + if [ -z "$2" ] || _check_o_direct; then + CACHEMODE="$1" + else + CACHEMODE="$2" + fi + QEMU_IO="$QEMU_IO --cache $CACHEMODE" + _check_cache_mode return fi } -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Test fails if bochs not whitelisted, so, skip it in this case. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-3-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/082 | 1 + 1 file changed, 1 insertion(+) diff --git a/tests/qemu-iotests/082 b/tests/qemu-iotests/082 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/082 +++ b/tests/qemu-iotests/082 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 _supported_fmt qcow2 _supported_proto file nfs +_require_drivers bochs run_qemu_img() { -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Skip test-case with quorum if quorum is not whitelisted. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-4-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/148 | 1 + 1 file changed, 1 insertion(+) diff --git a/tests/qemu-iotests/148 b/tests/qemu-iotests/148 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/148 +++ b/tests/qemu-iotests/148 @@ -XXX,XX +XXX,XX @@ sector = "%d" ''' % bad_sector) file.close() + @iotests.skip_if_unsupported(['quorum']) def setUp(self): driveopts = ['driver=quorum', 'vote-threshold=2'] driveopts.append('read-pattern=%s' % self.read_pattern) -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Drop check for no block-jobs: it's obvious that there no jobs immediately after vm.launch(). Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-5-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/041 | 8 -------- 1 file changed, 8 deletions(-) diff --git a/tests/qemu-iotests/041 b/tests/qemu-iotests/041 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/041 +++ b/tests/qemu-iotests/041 @@ -XXX,XX +XXX,XX @@ class TestRepairQuorum(iotests.QMPTestCase): pass def test_complete(self): - self.assert_no_active_block_jobs() - result = self.vm.qmp('drive-mirror', job_id='job0', device='quorum0', sync='full', node_name="repair0", replaces="img1", target=quorum_repair_img, format=iotests.imgfmt) @@ -XXX,XX +XXX,XX @@ class TestRepairQuorum(iotests.QMPTestCase): 'target image does not match source after mirroring') def test_cancel(self): - self.assert_no_active_block_jobs() - result = self.vm.qmp('drive-mirror', job_id='job0', device='quorum0', sync='full', node_name="repair0", replaces="img1", target=quorum_repair_img, format=iotests.imgfmt) @@ -XXX,XX +XXX,XX @@ class TestRepairQuorum(iotests.QMPTestCase): self.assert_has_block_node(None, quorum_img3) def test_cancel_after_ready(self): - self.assert_no_active_block_jobs() - result = self.vm.qmp('drive-mirror', job_id='job0', device='quorum0', sync='full', node_name="repair0", replaces="img1", target=quorum_repair_img, format=iotests.imgfmt) @@ -XXX,XX +XXX,XX @@ class TestRepairQuorum(iotests.QMPTestCase): 'target image does not match source after mirroring') def test_pause(self): - self.assert_no_active_block_jobs() - result = self.vm.qmp('drive-mirror', job_id='job0', device='quorum0', sync='full', node_name="repair0", replaces="img1", target=quorum_repair_img, format=iotests.imgfmt) -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Instead of looping in each test, let's better refactor vmdk target case as a subclass. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-6-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/055 | 70 ++++++++++++++++++++------------------ tests/qemu-iotests/055.out | 4 +-- 2 files changed, 39 insertions(+), 35 deletions(-) diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/055 +++ b/tests/qemu-iotests/055 @@ -XXX,XX +XXX,XX @@ class TestSingleTransaction(iotests.QMPTestCase): self.assert_no_active_block_jobs() -class TestDriveCompression(iotests.QMPTestCase): +class TestCompressedToQcow2(iotests.QMPTestCase): image_len = 64 * 1024 * 1024 # MB - fmt_supports_compression = [{'type': 'qcow2', 'args': ()}, - {'type': 'vmdk', 'args': ('-o', 'subformat=streamOptimized')}] + target_fmt = {'type': 'qcow2', 'args': ()} def tearDown(self): self.vm.shutdown() @@ -XXX,XX +XXX,XX @@ class TestDriveCompression(iotests.QMPTestCase): except OSError: pass - def do_prepare_drives(self, fmt, args, attach_target): + def do_prepare_drives(self, attach_target): self.vm = iotests.VM().add_drive('blkdebug::' + test_img) - qemu_img('create', '-f', fmt, blockdev_target_img, - str(TestDriveCompression.image_len), *args) + qemu_img('create', '-f', self.target_fmt['type'], blockdev_target_img, + str(self.image_len), *self.target_fmt['args']) if attach_target: self.vm.add_drive(blockdev_target_img, - img_format=fmt, interface="none") + img_format=self.target_fmt['type'], + interface="none") self.vm.launch() - def do_test_compress_complete(self, cmd, format, attach_target, **args): - self.do_prepare_drives(format['type'], format['args'], attach_target) + def do_test_compress_complete(self, cmd, attach_target, **args): + self.do_prepare_drives(attach_target) self.assert_no_active_block_jobs() @@ -XXX,XX +XXX,XX @@ class TestDriveCompression(iotests.QMPTestCase): self.vm.shutdown() self.assertTrue(iotests.compare_images(test_img, blockdev_target_img, - iotests.imgfmt, format['type']), + iotests.imgfmt, + self.target_fmt['type']), 'target image does not match source after backup') def test_complete_compress_drive_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_complete('drive-backup', format, False, - target=blockdev_target_img, mode='existing') + self.do_test_compress_complete('drive-backup', False, + target=blockdev_target_img, + mode='existing') def test_complete_compress_blockdev_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_complete('blockdev-backup', format, True, - target='drive1') + self.do_test_compress_complete('blockdev-backup', + True, target='drive1') - def do_test_compress_cancel(self, cmd, format, attach_target, **args): - self.do_prepare_drives(format['type'], format['args'], attach_target) + def do_test_compress_cancel(self, cmd, attach_target, **args): + self.do_prepare_drives(attach_target) self.assert_no_active_block_jobs() @@ -XXX,XX +XXX,XX @@ class TestDriveCompression(iotests.QMPTestCase): self.vm.shutdown() def test_compress_cancel_drive_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_cancel('drive-backup', format, False, - target=blockdev_target_img, mode='existing') + self.do_test_compress_cancel('drive-backup', False, + target=blockdev_target_img, + mode='existing') def test_compress_cancel_blockdev_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_cancel('blockdev-backup', format, True, - target='drive1') + self.do_test_compress_cancel('blockdev-backup', True, + target='drive1') - def do_test_compress_pause(self, cmd, format, attach_target, **args): - self.do_prepare_drives(format['type'], format['args'], attach_target) + def do_test_compress_pause(self, cmd, attach_target, **args): + self.do_prepare_drives(attach_target) self.assert_no_active_block_jobs() @@ -XXX,XX +XXX,XX @@ class TestDriveCompression(iotests.QMPTestCase): self.vm.shutdown() self.assertTrue(iotests.compare_images(test_img, blockdev_target_img, - iotests.imgfmt, format['type']), + iotests.imgfmt, + self.target_fmt['type']), 'target image does not match source after backup') def test_compress_pause_drive_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_pause('drive-backup', format, False, - target=blockdev_target_img, mode='existing') + self.do_test_compress_pause('drive-backup', False, + target=blockdev_target_img, + mode='existing') def test_compress_pause_blockdev_backup(self): - for format in TestDriveCompression.fmt_supports_compression: - self.do_test_compress_pause('blockdev-backup', format, True, - target='drive1') + self.do_test_compress_pause('blockdev-backup', True, + target='drive1') + + +class TestCompressedToVmdk(TestCompressedToQcow2): + target_fmt = {'type': 'vmdk', 'args': ('-o', 'subformat=streamOptimized')} + if __name__ == '__main__': iotests.main(supported_fmts=['raw', 'qcow2'], diff --git a/tests/qemu-iotests/055.out b/tests/qemu-iotests/055.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/055.out +++ b/tests/qemu-iotests/055.out @@ -XXX,XX +XXX,XX @@ -.............................. +.................................... ---------------------------------------------------------------------- -Ran 30 tests +Ran 36 tests OK -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-7-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/055 | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/055 +++ b/tests/qemu-iotests/055 @@ -XXX,XX +XXX,XX @@ class TestCompressedToQcow2(iotests.QMPTestCase): class TestCompressedToVmdk(TestCompressedToQcow2): target_fmt = {'type': 'vmdk', 'args': ('-o', 'subformat=streamOptimized')} + @iotests.skip_if_unsupported(['vmdk']) + def setUp(self): + pass + if __name__ == '__main__': iotests.main(supported_fmts=['raw', 'qcow2'], -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-8-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/109 | 1 + 1 file changed, 1 insertion(+) diff --git a/tests/qemu-iotests/109 b/tests/qemu-iotests/109 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/109 +++ b/tests/qemu-iotests/109 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 _supported_fmt raw _supported_proto file _supported_os Linux +_require_drivers qcow qcow2 qed vdi vmdk vpc qemu_comm_method=qmp -- 2.25.3 From: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200430124713.3067-9-vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/113 | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/qemu-iotests/113 b/tests/qemu-iotests/113 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/113 +++ b/tests/qemu-iotests/113 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 . ./common.rc . ./common.filter -# Some of these test cases use bochs, but others do use raw, so this -# is only half a lie. +# Some of these test cases use bochs, but others do use raw +_require_drivers bochs _supported_fmt raw _supported_proto file _supported_os Linux -- 2.25.3 From: Alberto Garcia <berto@igalia.com> After commit f01643fb8b47e8a70c04bbf45e0f12a9e5bc54de when an image is extended and BDRV_REQ_ZERO_WRITE is set then the new clusters are zeroized. The code however does not detect correctly situations when the old and the new end of the image are within the same cluster. The problem can be reproduced with these steps: qemu-img create -f qcow2 backing.qcow2 1M qemu-img create -f qcow2 -F qcow2 -b backing.qcow2 top.qcow2 qemu-img resize --shrink top.qcow2 520k qemu-img resize top.qcow2 567k In the last step offset - zero_start causes an integer wraparound. Signed-off-by: Alberto Garcia <berto@igalia.com> Message-Id: <20200504155217.10325-1-berto@igalia.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2.c | 12 ++++--- tests/qemu-iotests/292 | 73 ++++++++++++++++++++++++++++++++++++++ tests/qemu-iotests/292.out | 24 +++++++++++++ tests/qemu-iotests/group | 1 + 4 files changed, 105 insertions(+), 5 deletions(-) create mode 100755 tests/qemu-iotests/292 create mode 100644 tests/qemu-iotests/292.out 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_truncate(BlockDriverState *bs, int64_t offset, * requires a cluster-aligned start. The end may be unaligned if it is * at the end of the image (which it is here). */ - ret = qcow2_cluster_zeroize(bs, zero_start, offset - zero_start, 0); - if (ret < 0) { - error_setg_errno(errp, -ret, "Failed to zero out new clusters"); - goto fail; + if (offset > zero_start) { + ret = qcow2_cluster_zeroize(bs, zero_start, offset - zero_start, 0); + if (ret < 0) { + error_setg_errno(errp, -ret, "Failed to zero out new clusters"); + goto fail; + } } /* Write explicit zeros for the unaligned head */ if (zero_start > old_length) { - uint64_t len = zero_start - old_length; + uint64_t len = MIN(zero_start, offset) - old_length; uint8_t *buf = qemu_blockalign0(bs, len); QEMUIOVector qiov; qemu_iovec_init_buf(&qiov, buf, len); diff --git a/tests/qemu-iotests/292 b/tests/qemu-iotests/292 new file mode 100755 index XXXXXXX..XXXXXXX --- /dev/null +++ b/tests/qemu-iotests/292 @@ -XXX,XX +XXX,XX @@ +#!/usr/bin/env bash +# +# Test resizing a qcow2 image with a backing file +# +# Copyright (C) 2020 Igalia, S.L. +# Author: Alberto Garcia <berto@igalia.com> +# +# 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=berto@igalia.com + +seq=`basename $0` +echo "QA output created by $seq" + +status=1 # failure is the default! + +_cleanup() +{ + _cleanup_test_img +} +trap "_cleanup; exit \$status" 0 1 2 3 15 + +# get standard environment, filters and checks +. ./common.rc +. ./common.filter + +_supported_fmt qcow2 +_supported_proto file +_supported_os Linux + +echo '### Create the backing image' +BACKING_IMG="$TEST_IMG.base" +TEST_IMG="$BACKING_IMG" _make_test_img 1M + +echo '### Fill the backing image with data (0x11)' +$QEMU_IO -c 'write -P 0x11 0 1M' "$BACKING_IMG" | _filter_qemu_io + +echo '### Create the top image' +_make_test_img -F "$IMGFMT" -b "$BACKING_IMG" + +echo '### Fill the top image with data (0x22)' +$QEMU_IO -c 'write -P 0x22 0 1M' "$TEST_IMG" | _filter_qemu_io + +# Both offsets are part of the same cluster. +echo '### Shrink the image to 520k' +$QEMU_IMG resize --shrink "$TEST_IMG" 520k +echo '### Grow the image to 567k' +$QEMU_IMG resize "$TEST_IMG" 567k + +echo '### Check that the tail of the image reads as zeroes' +$QEMU_IO -c 'read -P 0x22 0 520k' "$TEST_IMG" | _filter_qemu_io +$QEMU_IO -c 'read -P 0x00 520k 47k' "$TEST_IMG" | _filter_qemu_io + +echo '### Show output of qemu-img map' +$QEMU_IMG map "$TEST_IMG" | _filter_testdir + +# success, all done +echo "*** done" +rm -f $seq.full +status=0 diff --git a/tests/qemu-iotests/292.out b/tests/qemu-iotests/292.out new file mode 100644 index XXXXXXX..XXXXXXX --- /dev/null +++ b/tests/qemu-iotests/292.out @@ -XXX,XX +XXX,XX @@ +QA output created by 292 +### Create the backing image +Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=1048576 +### Fill the backing image with data (0x11) +wrote 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +### Create the top image +Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 backing_file=TEST_DIR/t.IMGFMT.base backing_fmt=IMGFMT +### Fill the top image with data (0x22) +wrote 1048576/1048576 bytes at offset 0 +1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +### Shrink the image to 520k +Image resized. +### Grow the image to 567k +Image resized. +### Check that the tail of the image reads as zeroes +read 532480/532480 bytes at offset 0 +520 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +read 48128/48128 bytes at offset 532480 +47 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +### Show output of qemu-img map +Offset Length Mapped to File +0 0x8dc00 0x50000 TEST_DIR/t.qcow2 +*** 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 @@ 288 quick 289 rw quick 290 rw auto quick +292 rw auto quick -- 2.25.3 m_data is used for zero clusters even though valid == 0. It really only means that a new cluster was allocated in the image file. Rename it to reflect this. While at it, change it from int to bool, too. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-2-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 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 @@ typedef struct VmdkMetaData { unsigned int l1_index; unsigned int l2_index; unsigned int l2_offset; - int valid; + bool new_allocation; uint32_t *l2_cache_entry; } VmdkMetaData; @@ -XXX,XX +XXX,XX @@ static int get_cluster_offset(BlockDriverState *bs, unsigned int l2_size_bytes = extent->l2_size * extent->entry_size; if (m_data) { - m_data->valid = 0; + m_data->new_allocation = false; } if (extent->flat) { *cluster_offset = extent->flat_start_offset; @@ -XXX,XX +XXX,XX @@ static int get_cluster_offset(BlockDriverState *bs, return ret; } if (m_data) { - m_data->valid = 1; + m_data->new_allocation = true; m_data->l1_index = l1_index; m_data->l2_index = l2_index; m_data->l2_offset = l2_offset; @@ -XXX,XX +XXX,XX @@ static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset, if (ret) { return ret; } - if (m_data.valid) { + if (m_data.new_allocation) { /* update L2 tables */ if (vmdk_L2update(extent, &m_data, cluster_offset >> BDRV_SECTOR_BITS) -- 2.25.3 m_data must contain valid data even for zero clusters when no cluster was allocated in the image file. Without this, zero writes segfault with images that have zeroed_grain=on. For zero writes, we don't want to allocate a cluster in the image file even in compressed files. Fixes: 524089bce43fd1cd3daaca979872451efa2cf7c6 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-3-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 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 @@ static int get_cluster_offset(BlockDriverState *bs, extent->l2_cache_counts[min_index] = 1; found: l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size; + if (m_data) { + m_data->l1_index = l1_index; + m_data->l2_index = l2_index; + m_data->l2_offset = l2_offset; + m_data->l2_cache_entry = ((uint32_t *)l2_table) + l2_index; + } if (extent->sesparse) { cluster_sector = le64_to_cpu(((uint64_t *)l2_table)[l2_index]); @@ -XXX,XX +XXX,XX @@ static int get_cluster_offset(BlockDriverState *bs, } if (m_data) { m_data->new_allocation = true; - m_data->l1_index = l1_index; - m_data->l2_index = l2_index; - m_data->l2_offset = l2_offset; - m_data->l2_cache_entry = ((uint32_t *)l2_table) + l2_index; } } *cluster_offset = cluster_sector << BDRV_SECTOR_BITS; @@ -XXX,XX +XXX,XX @@ static int vmdk_pwritev(BlockDriverState *bs, uint64_t offset, error_report("Could not write to allocated cluster" " for streamOptimized"); return -EIO; - } else { + } else if (!zeroed) { /* allocate */ ret = get_cluster_offset(bs, extent, &m_data, offset, true, &cluster_offset, 0, 0); -- 2.25.3 When overwriting a zero cluster, we must not perform copy-on-write from the backing file, but from a zeroed buffer. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-4-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 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 @@ static void vmdk_refresh_limits(BlockDriverState *bs, Error **errp) * get_whole_cluster * * Copy backing file's cluster that covers @sector_num, otherwise write zero, - * to the cluster at @cluster_sector_num. + * to the cluster at @cluster_sector_num. If @zeroed is true, we're overwriting + * a zeroed cluster in the current layer and must not copy data from the + * backing file. * * If @skip_start_sector < @skip_end_sector, the relative range * [@skip_start_sector, @skip_end_sector) is not copied or written, and leave @@ -XXX,XX +XXX,XX @@ static int get_whole_cluster(BlockDriverState *bs, uint64_t cluster_offset, uint64_t offset, uint64_t skip_start_bytes, - uint64_t skip_end_bytes) + uint64_t skip_end_bytes, + bool zeroed) { int ret = VMDK_OK; int64_t cluster_bytes; uint8_t *whole_grain; + bool copy_from_backing; /* For COW, align request sector_num to cluster start */ cluster_bytes = extent->cluster_sectors << BDRV_SECTOR_BITS; offset = QEMU_ALIGN_DOWN(offset, cluster_bytes); whole_grain = qemu_blockalign(bs, cluster_bytes); + copy_from_backing = bs->backing && !zeroed; - if (!bs->backing) { + if (!copy_from_backing) { memset(whole_grain, 0, skip_start_bytes); memset(whole_grain + skip_end_bytes, 0, cluster_bytes - skip_end_bytes); } @@ -XXX,XX +XXX,XX @@ static int get_whole_cluster(BlockDriverState *bs, /* Read backing data before skip range */ if (skip_start_bytes > 0) { - if (bs->backing) { + if (copy_from_backing) { /* qcow2 emits this on bs->file instead of bs->backing */ BLKDBG_EVENT(extent->file, BLKDBG_COW_READ); ret = bdrv_pread(bs->backing, offset, whole_grain, @@ -XXX,XX +XXX,XX @@ static int get_whole_cluster(BlockDriverState *bs, } /* Read backing data after skip range */ if (skip_end_bytes < cluster_bytes) { - if (bs->backing) { + if (copy_from_backing) { /* qcow2 emits this on bs->file instead of bs->backing */ BLKDBG_EVENT(extent->file, BLKDBG_COW_READ); ret = bdrv_pread(bs->backing, offset + skip_end_bytes, @@ -XXX,XX +XXX,XX @@ static int get_cluster_offset(BlockDriverState *bs, * or inappropriate VM shutdown. */ ret = get_whole_cluster(bs, extent, cluster_sector * BDRV_SECTOR_SIZE, - offset, skip_start_bytes, skip_end_bytes); + offset, skip_start_bytes, skip_end_bytes, + zeroed); if (ret) { return ret; } -- 2.25.3 If a cluster is already zeroed, we don't have to call vmdk_L2update(), which is rather slow because it flushes the image file. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-5-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) 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 vmdk_pwritev(BlockDriverState *bs, uint64_t offset, offset_in_cluster == 0 && n_bytes >= extent->cluster_sectors * BDRV_SECTOR_SIZE) { n_bytes = extent->cluster_sectors * BDRV_SECTOR_SIZE; - if (!zero_dry_run) { + if (!zero_dry_run && ret != VMDK_ZEROED) { /* update L2 tables */ if (vmdk_L2update(extent, &m_data, VMDK_GTE_ZEROED) != VMDK_OK) { -- 2.25.3 If we have a backup L2 table, we currently flush once after writing to the active L2 table and again after writing to the backup table. A single flush is enough and makes things a little less slow. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-6-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vmdk.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 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 @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data, offset = cpu_to_le32(offset); /* update L2 table */ BLKDBG_EVENT(extent->file, BLKDBG_L2_UPDATE); - if (bdrv_pwrite_sync(extent->file, + if (bdrv_pwrite(extent->file, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(offset)), &offset, sizeof(offset)) < 0) { @@ -XXX,XX +XXX,XX @@ static int vmdk_L2update(VmdkExtent *extent, VmdkMetaData *m_data, /* update backup L2 table */ if (extent->l1_backup_table_offset != 0) { m_data->l2_offset = extent->l1_backup_table[m_data->l1_index]; - if (bdrv_pwrite_sync(extent->file, + if (bdrv_pwrite(extent->file, ((int64_t)m_data->l2_offset * 512) + (m_data->l2_index * sizeof(offset)), &offset, sizeof(offset)) < 0) { return VMDK_ERROR; } } + if (bdrv_flush(extent->file->bs) < 0) { + return VMDK_ERROR; + } if (m_data->l2_cache_entry) { *m_data->l2_cache_entry = offset; } -- 2.25.3 In order to avoid bitrot in the zero cluster code in VMDK, enable zeroed_grain=on by default for the tests. 059 now unsets the default options because zeroed_grain=on works only with some subformats and the test case tests many different subformats, including those for which it doesn't work. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430133007.170335-7-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/059 | 6 +++--- tests/qemu-iotests/check | 3 +++ 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/tests/qemu-iotests/059 b/tests/qemu-iotests/059 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/059 +++ b/tests/qemu-iotests/059 @@ -XXX,XX +XXX,XX @@ trap "_cleanup; exit \$status" 0 1 2 3 15 _supported_fmt vmdk _supported_proto file _supported_os Linux -_unsupported_imgopts "subformat=monolithicFlat" \ - "subformat=twoGbMaxExtentFlat" \ - "subformat=twoGbMaxExtentSparse" + +# We test all kinds of VMDK options here, so ignore user-specified options +IMGOPTS="" capacity_offset=16 granularity_offset=20 diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/check +++ b/tests/qemu-iotests/check @@ -XXX,XX +XXX,XX @@ fi if [ "$IMGFMT" == "luks" ] && ! (echo "$IMGOPTS" | grep "iter-time=" > /dev/null); then IMGOPTS=$(_optstr_add "$IMGOPTS" "iter-time=10") fi +if [ "$IMGFMT" == "vmdk" ] && ! (echo "$IMGOPTS" | grep "zeroed_grain=" > /dev/null); then + IMGOPTS=$(_optstr_add "$IMGOPTS" "zeroed_grain=on") +fi if [ -z "$SAMPLE_IMG_DIR" ]; then SAMPLE_IMG_DIR="$source_iotests/sample_images" -- 2.25.3 The test case forgot to specify the null-co size for the target node. When adding a check to backup that both sizes match, this would fail because of the size mismatch and not the behaviour that the test really wanted to test. Fixes: a541fcc27c98b96da187c7d4573f3270f3ddd283 Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430142755.315494-2-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/283 | 6 +++++- tests/qemu-iotests/283.out | 2 +- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/tests/qemu-iotests/283 b/tests/qemu-iotests/283 index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/283 +++ b/tests/qemu-iotests/283 @@ -XXX,XX +XXX,XX @@ to check that crash is fixed :) vm = iotests.VM() vm.launch() -vm.qmp_log('blockdev-add', **{'node-name': 'target', 'driver': 'null-co'}) +vm.qmp_log('blockdev-add', **{ + 'node-name': 'target', + 'driver': 'null-co', + 'size': size, +}) vm.qmp_log('blockdev-add', **{ 'node-name': 'source', diff --git a/tests/qemu-iotests/283.out b/tests/qemu-iotests/283.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/283.out +++ b/tests/qemu-iotests/283.out @@ -XXX,XX +XXX,XX @@ -{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "target"}} +{"execute": "blockdev-add", "arguments": {"driver": "null-co", "node-name": "target", "size": 1048576}} {"return": {}} {"execute": "blockdev-add", "arguments": {"driver": "blkdebug", "image": {"driver": "null-co", "node-name": "base", "size": 1048576}, "node-name": "source"}} {"return": {}} -- 2.25.3 bdrv_get_device_name() will be an empty string with modern management tools that don't use -drive. Use bdrv_get_device_or_node_name() instead so that the node name is used if the BlockBackend is anonymous. While at it, start with upper case to make the message consistent with the rest of the function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-Id: <20200430142755.315494-3-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/backup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, len = bdrv_getlength(bs); if (len < 0) { - error_setg_errno(errp, -len, "unable to get length for '%s'", - bdrv_get_device_name(bs)); + error_setg_errno(errp, -len, "Unable to get length for '%s'", + bdrv_get_device_or_node_name(bs)); goto error; } -- 2.25.3 Since the introduction of a backup filter node in commit 00e30f05d, the backup block job crashes when the target image is smaller than the source image because it will try to write after the end of the target node without having BLK_PERM_RESIZE. (Previously, the BlockBackend layer would have caught this and errored out gracefully.) We can fix this and even do better than the old behaviour: Check that source and target have the same image size at the start of the block job and unshare BLK_PERM_RESIZE. (This permission was already unshared before the same commit 00e30f05d, but the BlockBackend that was used to make the restriction was removed without a replacement.) This will immediately error out when starting the job instead of only when writing to a block that doesn't exist in the target. Longer target than source would technically work because we would never write to blocks that don't exist, but semantically these are invalid, too, because a backup is supposed to create a copy, not just an image that starts with a copy. Fixes: 00e30f05de1d19586345ec373970ef4c192c6270 Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1778593 Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430142755.315494-4-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/backup-top.c | 14 +++++++++----- block/backup.c | 14 +++++++++++++- 2 files changed, 22 insertions(+), 6 deletions(-) diff --git a/block/backup-top.c b/block/backup-top.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup-top.c +++ b/block/backup-top.c @@ -XXX,XX +XXX,XX @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c, * * Share write to target (child_file), to not interfere * with guest writes to its disk which may be in target backing chain. + * Can't resize during a backup block job because we check the size + * only upfront. */ - *nshared = BLK_PERM_ALL; + *nshared = BLK_PERM_ALL & ~BLK_PERM_RESIZE; *nperm = BLK_PERM_WRITE; } else { /* Source child */ @@ -XXX,XX +XXX,XX @@ static void backup_top_child_perm(BlockDriverState *bs, BdrvChild *c, if (perm & BLK_PERM_WRITE) { *nperm = *nperm | BLK_PERM_CONSISTENT_READ; } - *nshared &= ~BLK_PERM_WRITE; + *nshared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); } } @@ -XXX,XX +XXX,XX @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, { Error *local_err = NULL; BDRVBackupTopState *state; - BlockDriverState *top = bdrv_new_open_driver(&bdrv_backup_top_filter, - filter_node_name, - BDRV_O_RDWR, errp); + BlockDriverState *top; bool appended = false; + assert(source->total_sectors == target->total_sectors); + + top = bdrv_new_open_driver(&bdrv_backup_top_filter, filter_node_name, + BDRV_O_RDWR, errp); if (!top) { return NULL; } diff --git a/block/backup.c b/block/backup.c index XXXXXXX..XXXXXXX 100644 --- a/block/backup.c +++ b/block/backup.c @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, BlockCompletionFunc *cb, void *opaque, JobTxn *txn, Error **errp) { - int64_t len; + int64_t len, target_len; BackupBlockJob *job = NULL; int64_t cluster_size; BdrvRequestFlags write_flags; @@ -XXX,XX +XXX,XX @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, goto error; } + target_len = bdrv_getlength(target); + if (target_len < 0) { + error_setg_errno(errp, -target_len, "Unable to get length for '%s'", + bdrv_get_device_or_node_name(bs)); + goto error; + } + + if (target_len != len) { + error_setg(errp, "Source and target image have different sizes"); + goto error; + } + cluster_size = backup_calculate_cluster_size(target, errp); if (cluster_size < 0) { goto error; -- 2.25.3 This tests that the backup job catches situations where the target node has a different size than the source node. It must also forbid resize operations when the job is already running. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200430142755.315494-5-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/055 | 41 ++++++++++++++++++++++++++++++++++++-- tests/qemu-iotests/055.out | 4 ++-- 2 files changed, 41 insertions(+), 4 deletions(-) diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/055 +++ b/tests/qemu-iotests/055 @@ -XXX,XX +XXX,XX @@ class TestSingleDrive(iotests.QMPTestCase): def setUp(self): qemu_img('create', '-f', iotests.imgfmt, blockdev_target_img, str(image_len)) - self.vm = iotests.VM().add_drive('blkdebug::' + test_img) - self.vm.add_drive(blockdev_target_img, interface="none") + self.vm = iotests.VM() + self.vm.add_drive('blkdebug::' + test_img, 'node-name=source') + self.vm.add_drive(blockdev_target_img, 'node-name=target', + interface="none") if iotests.qemu_default_machine == 'pc': self.vm.add_drive(None, 'media=cdrom', 'ide') self.vm.launch() @@ -XXX,XX +XXX,XX @@ class TestSingleDrive(iotests.QMPTestCase): def test_pause_blockdev_backup(self): self.do_test_pause('blockdev-backup', 'drive1', blockdev_target_img) + def do_test_resize_blockdev_backup(self, device, node): + def pre_finalize(): + result = self.vm.qmp('block_resize', device=device, size=65536) + self.assert_qmp(result, 'error/class', 'GenericError') + + result = self.vm.qmp('block_resize', node_name=node, size=65536) + self.assert_qmp(result, 'error/class', 'GenericError') + + result = self.vm.qmp('blockdev-backup', job_id='job0', device='drive0', + target='drive1', sync='full', auto_finalize=False, + auto_dismiss=False) + self.assert_qmp(result, 'return', {}) + + self.vm.run_job('job0', auto_finalize=False, pre_finalize=pre_finalize) + + def test_source_resize_blockdev_backup(self): + self.do_test_resize_blockdev_backup('drive0', 'source') + + def test_target_resize_blockdev_backup(self): + self.do_test_resize_blockdev_backup('drive1', 'target') + + def do_test_target_size(self, size): + result = self.vm.qmp('block_resize', device='drive1', size=size) + self.assert_qmp(result, 'return', {}) + + result = self.vm.qmp('blockdev-backup', job_id='job0', device='drive0', + target='drive1', sync='full') + self.assert_qmp(result, 'error/class', 'GenericError') + + def test_small_target(self): + self.do_test_target_size(image_len // 2) + + def test_large_target(self): + self.do_test_target_size(image_len * 2) + def test_medium_not_found(self): if iotests.qemu_default_machine != 'pc': return diff --git a/tests/qemu-iotests/055.out b/tests/qemu-iotests/055.out index XXXXXXX..XXXXXXX 100644 --- a/tests/qemu-iotests/055.out +++ b/tests/qemu-iotests/055.out @@ -XXX,XX +XXX,XX @@ -.................................... +........................................ ---------------------------------------------------------------------- -Ran 36 tests +Ran 40 tests OK -- 2.25.3 055 uses the backup block job to create a compressed backup of an $IMGFMT image with both qcow2 and vmdk targets. However, cluster allocation in vmdk is very slow because it flushes the image file after each L2 update. There is no reason why we need this level of safety in this test, so let's disable flushes for vmdk. For the blockdev-backup tests this is achieved by simply adding the cache.no-flush=on to the drive_add() for the target. For drive-backup, the caching flags are copied from the source node, so we'll also add the flag to the source node, even though it is not vmdk. This can make the test run significantly faster (though it doesn't make a difference on tmpfs). In my usual setup it goes from ~45s to ~15s. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200505064618.16267-1-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- tests/qemu-iotests/055 | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/tests/qemu-iotests/055 b/tests/qemu-iotests/055 index XXXXXXX..XXXXXXX 100755 --- a/tests/qemu-iotests/055 +++ b/tests/qemu-iotests/055 @@ -XXX,XX +XXX,XX @@ class TestSingleTransaction(iotests.QMPTestCase): class TestCompressedToQcow2(iotests.QMPTestCase): image_len = 64 * 1024 * 1024 # MB - target_fmt = {'type': 'qcow2', 'args': ()} + target_fmt = {'type': 'qcow2', 'args': (), 'drive-opts': ''} def tearDown(self): self.vm.shutdown() @@ -XXX,XX +XXX,XX @@ class TestCompressedToQcow2(iotests.QMPTestCase): pass def do_prepare_drives(self, attach_target): - self.vm = iotests.VM().add_drive('blkdebug::' + test_img) + self.vm = iotests.VM().add_drive('blkdebug::' + test_img, + opts=self.target_fmt['drive-opts']) qemu_img('create', '-f', self.target_fmt['type'], blockdev_target_img, str(self.image_len), *self.target_fmt['args']) if attach_target: self.vm.add_drive(blockdev_target_img, img_format=self.target_fmt['type'], - interface="none") + interface="none", + opts=self.target_fmt['drive-opts']) self.vm.launch() @@ -XXX,XX +XXX,XX @@ class TestCompressedToQcow2(iotests.QMPTestCase): class TestCompressedToVmdk(TestCompressedToQcow2): - target_fmt = {'type': 'vmdk', 'args': ('-o', 'subformat=streamOptimized')} + target_fmt = {'type': 'vmdk', 'args': ('-o', 'subformat=streamOptimized'), + 'drive-opts': 'cache.no-flush=on'} @iotests.skip_if_unsupported(['vmdk']) def setUp(self): -- 2.25.3 From: Max Reitz <mreitz@redhat.com> Calling bdrv_getlength() to get the pre-truncate file size will not really work on block devices, because they have always the same length, and trying to write beyond it will fail with a rather cryptic error message. Instead, we should use qcow2_get_last_cluster() and bdrv_getlength() only as a fallback. Before this patch: $ truncate -s 1G test.img $ sudo losetup -f --show test.img /dev/loop0 $ sudo qemu-img create -f qcow2 -o preallocation=full /dev/loop0 64M Formatting '/dev/loop0', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=full lazy_refcounts=off refcount_bits=16 qemu-img: /dev/loop0: Could not resize image: Failed to resize refcount structures: No space left on device With this patch: $ sudo qemu-img create -f qcow2 -o preallocation=full /dev/loop0 64M Formatting '/dev/loop0', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=full lazy_refcounts=off refcount_bits=16 qemu-img: /dev/loop0: Could not resize image: Failed to resize underlying file: Preallocation mode 'full' unsupported for this non-regular file So as you can see, it still fails, but now the problem is missing support on the block device level, so we at least get a better error message. Note that we cannot preallocate block devices on truncate by design, because we do not know what area to preallocate. Their length is always the same, the truncate operation does not change it. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200505141801.1096763-1-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/qcow2.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 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 coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset, { int64_t allocation_start, host_offset, guest_offset; int64_t clusters_allocated; - int64_t old_file_size, new_file_size; + int64_t old_file_size, last_cluster, new_file_size; uint64_t nb_new_data_clusters, nb_new_l2_tables; /* With a data file, preallocation means just allocating the metadata @@ -XXX,XX +XXX,XX @@ static int coroutine_fn qcow2_co_truncate(BlockDriverState *bs, int64_t offset, ret = old_file_size; goto fail; } - old_file_size = ROUND_UP(old_file_size, s->cluster_size); + + last_cluster = qcow2_get_last_cluster(bs, old_file_size); + if (last_cluster >= 0) { + old_file_size = (last_cluster + 1) * s->cluster_size; + } else { + old_file_size = ROUND_UP(old_file_size, s->cluster_size); + } nb_new_data_clusters = DIV_ROUND_UP(offset - old_length, s->cluster_size); -- 2.25.3 From: Eric Blake <eblake@redhat.com> block.c already defaults to 0 if we don't provide a callback; there's no need to write a callback that always fails. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-Id: <20200428202905.770727-2-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/gluster.c | 14 -------------- 1 file changed, 14 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 int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs) } } -static int qemu_gluster_has_zero_init(BlockDriverState *bs) -{ - /* GlusterFS volume could be backed by a block device */ - return 0; -} - /* * Find allocation range in @bs around offset @start. * May change underlying file descriptor's file offset. @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_gluster = { .bdrv_co_readv = qemu_gluster_co_readv, .bdrv_co_writev = qemu_gluster_co_writev, .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, - .bdrv_has_zero_init = qemu_gluster_has_zero_init, - .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, #ifdef CONFIG_GLUSTERFS_DISCARD .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, #endif @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_gluster_tcp = { .bdrv_co_readv = qemu_gluster_co_readv, .bdrv_co_writev = qemu_gluster_co_writev, .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, - .bdrv_has_zero_init = qemu_gluster_has_zero_init, - .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, #ifdef CONFIG_GLUSTERFS_DISCARD .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, #endif @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_gluster_unix = { .bdrv_co_readv = qemu_gluster_co_readv, .bdrv_co_writev = qemu_gluster_co_writev, .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, - .bdrv_has_zero_init = qemu_gluster_has_zero_init, - .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, #ifdef CONFIG_GLUSTERFS_DISCARD .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, #endif @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_gluster_rdma = { .bdrv_co_readv = qemu_gluster_co_readv, .bdrv_co_writev = qemu_gluster_co_writev, .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, - .bdrv_has_zero_init = qemu_gluster_has_zero_init, - .bdrv_has_zero_init_truncate = qemu_gluster_has_zero_init, #ifdef CONFIG_GLUSTERFS_DISCARD .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, #endif -- 2.25.3 From: Eric Blake <eblake@redhat.com> When using bdrv_file, .bdrv_has_zero_init_truncate always returns 1; therefore, we can behave just like file-posix, and always implement BDRV_REQ_ZERO_WRITE by ignoring it since the OS gives it to us for free (note that file-posix.c had to use an 'if' because it shared code between regular files and block devices, but in file-win32.c, bdrv_host_device uses a separate .bdrv_file_open). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-3-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/file-win32.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/file-win32.c b/block/file-win32.c index XXXXXXX..XXXXXXX 100644 --- a/block/file-win32.c +++ b/block/file-win32.c @@ -XXX,XX +XXX,XX @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags, win32_aio_attach_aio_context(s->aio, bdrv_get_aio_context(bs)); } + /* When extending regular files, we get zeros from the OS */ + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + ret = 0; fail: qemu_opts_del(opts); -- 2.25.3 From: Eric Blake <eblake@redhat.com> Our .bdrv_has_zero_init_truncate returns 1 if we detect that the OS always 0-fills; we can use that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it when the OS gives it to us for free. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-4-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/nfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/nfs.c b/block/nfs.c index XXXXXXX..XXXXXXX 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -XXX,XX +XXX,XX @@ static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags, } bs->total_sectors = ret; + if (client->has_zero_init) { + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + } return 0; } -- 2.25.3 From: Eric Blake <eblake@redhat.com> Our .bdrv_has_zero_init_truncate always returns 1 because rbd always 0-fills; we can use that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-5-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/rbd.c | 3 +++ 1 file changed, 3 insertions(+) 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, } } + /* When extending regular files, we get zeros from the OS */ + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + r = 0; goto out; -- 2.25.3 From: Eric Blake <eblake@redhat.com> Our .bdrv_has_zero_init_truncate always returns 1 because sheepdog always 0-fills; we can use that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-6-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/sheepdog.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/sheepdog.c b/block/sheepdog.c index XXXXXXX..XXXXXXX 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -XXX,XX +XXX,XX @@ static int sd_open(BlockDriverState *bs, QDict *options, int flags, memcpy(&s->inode, buf, sizeof(s->inode)); bs->total_sectors = s->inode.vdi_size / BDRV_SECTOR_SIZE; + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; pstrcpy(s->name, sizeof(s->name), vdi); qemu_co_mutex_init(&s->lock); qemu_co_mutex_init(&s->queue_lock); -- 2.25.3 From: Eric Blake <eblake@redhat.com> Our .bdrv_has_zero_init_truncate can detect when the remote side always zero fills; we can reuse that same knowledge to implement BDRV_REQ_ZERO_WRITE by ignoring it when the server gives it to us for free. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-7-eblake@redhat.com> Reviewed-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/ssh.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/block/ssh.c b/block/ssh.c index XXXXXXX..XXXXXXX 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -XXX,XX +XXX,XX @@ static int ssh_file_open(BlockDriverState *bs, QDict *options, int bdrv_flags, /* Go non-blocking. */ ssh_set_blocking(s->session, 0); + if (s->attrs->type == SSH_FILEXFER_TYPE_REGULAR) { + bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE; + } + qapi_free_BlockdevOptionsSsh(opts); return 0; -- 2.25.3 From: Eric Blake <eblake@redhat.com> The parallels driver tries to use truncation for image growth, but can only do so when reads are guaranteed as zero. Now that we have a way to request zero contents from truncation, we can defer the decision to actual allocation attempts rather than up front, reducing the number of places that still use bdrv_has_zero_init_truncate. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-8-eblake@redhat.com> Reviewed-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/parallels.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) 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 int64_t block_status(BDRVParallelsState *s, int64_t sector_num, static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum) { - int ret; + int ret = 0; BDRVParallelsState *s = bs->opaque; int64_t pos, space, idx, to_allocate, i, len; @@ -XXX,XX +XXX,XX @@ static int64_t allocate_clusters(BlockDriverState *bs, int64_t sector_num, } if (s->data_end + space > (len >> BDRV_SECTOR_BITS)) { space += s->prealloc_size; + /* + * We require the expanded size to read back as zero. If the + * user permitted truncation, we try that; but if it fails, we + * force the safer-but-slower fallocate. + */ + if (s->prealloc_mode == PRL_PREALLOC_MODE_TRUNCATE) { + ret = bdrv_truncate(bs->file, + (s->data_end + space) << BDRV_SECTOR_BITS, + false, PREALLOC_MODE_OFF, BDRV_REQ_ZERO_WRITE, + NULL); + if (ret == -ENOTSUP) { + s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE; + } + } if (s->prealloc_mode == PRL_PREALLOC_MODE_FALLOCATE) { ret = bdrv_pwrite_zeroes(bs->file, s->data_end << BDRV_SECTOR_BITS, space << BDRV_SECTOR_BITS, 0); - } else { - ret = bdrv_truncate(bs->file, - (s->data_end + space) << BDRV_SECTOR_BITS, - false, PREALLOC_MODE_OFF, 0, NULL); } if (ret < 0) { return ret; @@ -XXX,XX +XXX,XX @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags, qemu_opt_get_size_del(opts, PARALLELS_OPT_PREALLOC_SIZE, 0); s->prealloc_size = MAX(s->tracks, s->prealloc_size >> BDRV_SECTOR_BITS); buf = qemu_opt_get_del(opts, PARALLELS_OPT_PREALLOC_MODE); + /* prealloc_mode can be downgraded later during allocate_clusters */ s->prealloc_mode = qapi_enum_parse(&prealloc_mode_lookup, buf, PRL_PREALLOC_MODE_FALLOCATE, &local_err); @@ -XXX,XX +XXX,XX @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags, goto fail_options; } - if (!bdrv_has_zero_init_truncate(bs->file->bs)) { - s->prealloc_mode = PRL_PREALLOC_MODE_FALLOCATE; - } - if ((flags & BDRV_O_RDWR) && !(flags & BDRV_O_INACTIVE)) { s->header->inuse = cpu_to_le32(HEADER_INUSE_MAGIC); ret = parallels_update_header(bs); -- 2.25.3 From: Eric Blake <eblake@redhat.com> The vhdx driver uses truncation for image growth, with a special case for blocks that already read as zero but which are only being partially written. But with a bit of rearranging, it's just as easy to defer the decision on whether truncation resulted in zeroes to the actual allocation attempt, reducing the number of places that still use bdrv_has_zero_init_truncate. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-9-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- block/vhdx.c | 89 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 51 insertions(+), 38 deletions(-) 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 @@ exit: /* * Allocate a new payload block at the end of the file. * - * Allocation will happen at 1MB alignment inside the file + * Allocation will happen at 1MB alignment inside the file. + * + * If @need_zero is set on entry but not cleared on return, then truncation + * could not guarantee that the new portion reads as zero, and the caller + * will take care of it instead. * * Returns the file offset start of the new payload block */ static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, - uint64_t *new_offset) + uint64_t *new_offset, bool *need_zero) { int64_t current_len; @@ -XXX,XX +XXX,XX @@ static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, return -EINVAL; } + if (*need_zero) { + int ret; + + ret = bdrv_truncate(bs->file, *new_offset + s->block_size, false, + PREALLOC_MODE_OFF, BDRV_REQ_ZERO_WRITE, NULL); + if (ret != -ENOTSUP) { + *need_zero = false; + return ret; + } + } + return bdrv_truncate(bs->file, *new_offset + s->block_size, false, PREALLOC_MODE_OFF, 0, NULL); } @@ -XXX,XX +XXX,XX @@ static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, /* in this case, we need to preserve zero writes for * data that is not part of this write, so we must pad * the rest of the buffer to zeroes */ - - /* if we are on a posix system with ftruncate() that extends - * a file, then it is zero-filled for us. On Win32, the raw - * layer uses SetFilePointer and SetFileEnd, which does not - * zero fill AFAIK */ - - /* Queue another write of zero buffers if the underlying file - * does not zero-fill on file extension */ - - if (bdrv_has_zero_init_truncate(bs->file->bs) == 0) { - use_zero_buffers = true; - + use_zero_buffers = true; + /* fall through */ + case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ + case PAYLOAD_BLOCK_UNMAPPED: + case PAYLOAD_BLOCK_UNMAPPED_v095: + case PAYLOAD_BLOCK_UNDEFINED: + bat_prior_offset = sinfo.file_offset; + ret = vhdx_allocate_block(bs, s, &sinfo.file_offset, + &use_zero_buffers); + if (ret < 0) { + goto exit; + } + /* + * once we support differencing files, this may also be + * partially present + */ + /* update block state to the newly specified state */ + vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, + &bat_entry_offset, + PAYLOAD_BLOCK_FULLY_PRESENT); + bat_update = true; + /* + * Since we just allocated a block, file_offset is the + * beginning of the payload block. It needs to be the + * write address, which includes the offset into the + * block, unless the entire block needs to read as + * zeroes but truncation was not able to provide them, + * in which case we need to fill in the rest. + */ + if (!use_zero_buffers) { + sinfo.file_offset += sinfo.block_offset; + } else { /* zero fill the front, if any */ if (sinfo.block_offset) { iov1.iov_len = sinfo.block_offset; @@ -XXX,XX +XXX,XX @@ static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, } /* our actual data */ - qemu_iovec_concat(&hd_qiov, qiov, bytes_done, + qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); /* zero fill the back, if any */ @@ -XXX,XX +XXX,XX @@ static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; } } - /* fall through */ - case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ - case PAYLOAD_BLOCK_UNMAPPED: - case PAYLOAD_BLOCK_UNMAPPED_v095: - case PAYLOAD_BLOCK_UNDEFINED: - bat_prior_offset = sinfo.file_offset; - ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); - if (ret < 0) { - goto exit; - } - /* once we support differencing files, this may also be - * partially present */ - /* update block state to the newly specified state */ - vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, - &bat_entry_offset, - PAYLOAD_BLOCK_FULLY_PRESENT); - bat_update = true; - /* since we just allocated a block, file_offset is the - * beginning of the payload block. It needs to be the - * write address, which includes the offset into the block */ - if (!use_zero_buffers) { - sinfo.file_offset += sinfo.block_offset; - } + /* fall through */ case PAYLOAD_BLOCK_FULLY_PRESENT: /* if the file offset address is in the header zone, -- 2.25.3 From: Eric Blake <eblake@redhat.com> Now that there are no clients of bdrv_has_zero_init_truncate, none of the drivers need to worry about providing it. What's more, this eliminates a source of some confusion: a literal reading of the documentation as written in ceaca56f and implemented in commit 1dcaf527 claims that a driver which returns 0 for bdrv_has_zero_init_truncate() must not return 1 for bdrv_has_zero_init(); this condition was violated for parallels, qcow, and sometimes for vdi, although in practice it did not matter since those drivers also lacked .bdrv_co_truncate. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200428202905.770727-10-eblake@redhat.com> Acked-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> --- include/block/block.h | 1 - include/block/block_int.h | 7 ------- block.c | 21 --------------------- block/file-posix.c | 1 - block/file-win32.c | 1 - block/nfs.c | 1 - block/qcow2.c | 1 - block/qed.c | 1 - block/raw-format.c | 6 ------ block/rbd.c | 1 - block/sheepdog.c | 3 --- block/ssh.c | 1 - 12 files changed, 45 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_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); int bdrv_has_zero_init_1(BlockDriverState *bs); int bdrv_has_zero_init(BlockDriverState *bs); -int bdrv_has_zero_init_truncate(BlockDriverState *bs); bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); int bdrv_block_status(BlockDriverState *bs, int64_t offset, 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 @@ struct BlockDriver { /* * Returns 1 if newly created images are guaranteed to contain only * zeros, 0 otherwise. - * Must return 0 if .bdrv_has_zero_init_truncate() returns 0. */ int (*bdrv_has_zero_init)(BlockDriverState *bs); - /* - * Returns 1 if new areas added by growing the image with - * PREALLOC_MODE_OFF contain only zeros, 0 otherwise. - */ - int (*bdrv_has_zero_init_truncate)(BlockDriverState *bs); - /* Remove fd handlers, timers, and other event loop callbacks so the event * loop is no longer in use. Called with no in-flight requests and in * depth-first traversal order with parents before child nodes. diff --git a/block.c b/block.c index XXXXXXX..XXXXXXX 100644 --- a/block.c +++ b/block.c @@ -XXX,XX +XXX,XX @@ int bdrv_has_zero_init(BlockDriverState *bs) return 0; } -int bdrv_has_zero_init_truncate(BlockDriverState *bs) -{ - if (!bs->drv) { - return 0; - } - - if (bs->backing) { - /* Depends on the backing image length, but better safe than sorry */ - return 0; - } - if (bs->drv->bdrv_has_zero_init_truncate) { - return bs->drv->bdrv_has_zero_init_truncate(bs); - } - if (bs->file && bs->drv->is_filter) { - return bdrv_has_zero_init_truncate(bs->file->bs); - } - - /* safe default */ - return 0; -} - bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs) { BlockDriverInfo bdi; 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 @@ BlockDriver bdrv_file = { .bdrv_co_create = raw_co_create, .bdrv_co_create_opts = raw_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_co_block_status = raw_co_block_status, .bdrv_co_invalidate_cache = raw_co_invalidate_cache, .bdrv_co_pwrite_zeroes = raw_co_pwrite_zeroes, diff --git a/block/file-win32.c b/block/file-win32.c index XXXXXXX..XXXXXXX 100644 --- a/block/file-win32.c +++ b/block/file-win32.c @@ -XXX,XX +XXX,XX @@ BlockDriver bdrv_file = { .bdrv_close = raw_close, .bdrv_co_create_opts = raw_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_aio_preadv = raw_aio_preadv, .bdrv_aio_pwritev = raw_aio_pwritev, diff --git a/block/nfs.c b/block/nfs.c index XXXXXXX..XXXXXXX 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_nfs = { .create_opts = &nfs_create_opts, .bdrv_has_zero_init = nfs_has_zero_init, - .bdrv_has_zero_init_truncate = nfs_has_zero_init, .bdrv_get_allocated_file_size = nfs_get_allocated_file_size, .bdrv_co_truncate = nfs_file_co_truncate, 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 @@ BlockDriver bdrv_qcow2 = { .bdrv_co_create_opts = qcow2_co_create_opts, .bdrv_co_create = qcow2_co_create, .bdrv_has_zero_init = qcow2_has_zero_init, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_co_block_status = qcow2_co_block_status, .bdrv_co_preadv_part = qcow2_co_preadv_part, 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 BlockDriver bdrv_qed = { .bdrv_co_create = bdrv_qed_co_create, .bdrv_co_create_opts = bdrv_qed_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_co_block_status = bdrv_qed_co_block_status, .bdrv_co_readv = bdrv_qed_co_readv, .bdrv_co_writev = bdrv_qed_co_writev, 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 raw_has_zero_init(BlockDriverState *bs) return bdrv_has_zero_init(bs->file->bs); } -static int raw_has_zero_init_truncate(BlockDriverState *bs) -{ - return bdrv_has_zero_init_truncate(bs->file->bs); -} - static int coroutine_fn raw_co_create_opts(BlockDriver *drv, const char *filename, QemuOpts *opts, @@ -XXX,XX +XXX,XX @@ BlockDriver bdrv_raw = { .bdrv_co_ioctl = &raw_co_ioctl, .create_opts = &raw_create_opts, .bdrv_has_zero_init = &raw_has_zero_init, - .bdrv_has_zero_init_truncate = &raw_has_zero_init_truncate, .strong_runtime_opts = raw_strong_runtime_opts, .mutable_opts = mutable_opts, }; 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 BlockDriver bdrv_rbd = { .bdrv_co_create = qemu_rbd_co_create, .bdrv_co_create_opts = qemu_rbd_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_get_info = qemu_rbd_getinfo, .create_opts = &qemu_rbd_create_opts, .bdrv_getlength = qemu_rbd_getlength, diff --git a/block/sheepdog.c b/block/sheepdog.c index XXXXXXX..XXXXXXX 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_sheepdog = { .bdrv_co_create = sd_co_create, .bdrv_co_create_opts = sd_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_getlength = sd_getlength, .bdrv_get_allocated_file_size = sd_get_allocated_file_size, .bdrv_co_truncate = sd_co_truncate, @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_sheepdog_tcp = { .bdrv_co_create = sd_co_create, .bdrv_co_create_opts = sd_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_getlength = sd_getlength, .bdrv_get_allocated_file_size = sd_get_allocated_file_size, .bdrv_co_truncate = sd_co_truncate, @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_sheepdog_unix = { .bdrv_co_create = sd_co_create, .bdrv_co_create_opts = sd_co_create_opts, .bdrv_has_zero_init = bdrv_has_zero_init_1, - .bdrv_has_zero_init_truncate = bdrv_has_zero_init_1, .bdrv_getlength = sd_getlength, .bdrv_get_allocated_file_size = sd_get_allocated_file_size, .bdrv_co_truncate = sd_co_truncate, diff --git a/block/ssh.c b/block/ssh.c index XXXXXXX..XXXXXXX 100644 --- a/block/ssh.c +++ b/block/ssh.c @@ -XXX,XX +XXX,XX @@ static BlockDriver bdrv_ssh = { .bdrv_co_create_opts = ssh_co_create_opts, .bdrv_close = ssh_close, .bdrv_has_zero_init = ssh_has_zero_init, - .bdrv_has_zero_init_truncate = ssh_has_zero_init, .bdrv_co_readv = ssh_co_readv, .bdrv_co_writev = ssh_co_writev, .bdrv_getlength = ssh_getlength, -- 2.25.3