The way that attaching bs->file worked was a bit unusual in that it was
the only child that would be attached to a node which is not opened yet.
Because of this, the block layer couldn't know yet which permissions the
driver would eventually need.
This patch moves the point where bs->file is attached to the beginning
of the individual .bdrv_open() implementations, so drivers already know
what they are going to do with the child. This is also more consistent
with how driver-specific children work.
bdrv_open() still needs its own BdrvChild to perform image probing, but
instead of directly assigning this BdrvChild to the BDS, it becomes a
temporary one and the node name is passed as an option to the drivers,
so that they can simply use bdrv_open_child() to create another
reference for their own use.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
block.c | 34 +++++++++++++++++++++++-----------
block/bochs.c | 6 ++++++
block/cloop.c | 6 ++++++
block/crypto.c | 6 ++++++
block/dmg.c | 6 ++++++
block/parallels.c | 6 ++++++
block/qcow.c | 6 ++++++
block/qcow2.c | 18 +++++++++++++++---
block/qed.c | 18 +++++++++++++++---
block/raw-format.c | 6 ++++++
block/replication.c | 6 ++++++
block/vdi.c | 6 ++++++
block/vhdx.c | 6 ++++++
block/vmdk.c | 6 ++++++
block/vpc.c | 6 ++++++
tests/qemu-iotests/051.out | 4 ++--
tests/qemu-iotests/051.pc.out | 4 ++--
17 files changed, 129 insertions(+), 21 deletions(-)
diff --git a/block.c b/block.c
index 743c349..0618f4b 100644
--- a/block.c
+++ b/block.c
@@ -1103,13 +1103,6 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file,
assert(!drv->bdrv_needs_filename || filename != NULL);
ret = drv->bdrv_file_open(bs, options, open_flags, &local_err);
} else {
- if (file == NULL) {
- error_setg(errp, "Can't use '%s' as a block driver for the "
- "protocol level", drv->format_name);
- ret = -EINVAL;
- goto free_and_fail;
- }
- bs->file = file;
ret = drv->bdrv_open(bs, options, open_flags, &local_err);
}
@@ -1145,7 +1138,6 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file,
return 0;
free_and_fail:
- bs->file = NULL;
g_free(bs->opaque);
bs->opaque = NULL;
bs->drv = NULL;
@@ -1368,7 +1360,18 @@ void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child)
}
if (child->bs->inherits_from == parent) {
- child->bs->inherits_from = NULL;
+ BdrvChild *c;
+
+ /* Remove inherits_from only when the last reference between parent and
+ * child->bs goes away. */
+ QLIST_FOREACH(c, &parent->children, next) {
+ if (c != child && c->bs == child->bs) {
+ break;
+ }
+ }
+ if (c == NULL) {
+ child->bs->inherits_from = NULL;
+ }
}
bdrv_root_unref_child(child);
@@ -1789,13 +1792,19 @@ static BlockDriverState *bdrv_open_inherit(const char *filename,
qdict_del(options, "backing");
}
- /* Open image file without format layer */
+ /* Open image file without format layer. This BdrvChild is only used for
+ * probing, the block drivers will do their own bdrv_open_child() for the
+ * same BDS, which is why we put the node name back into options. */
if ((flags & BDRV_O_PROTOCOL) == 0) {
file = bdrv_open_child(filename, options, "file", bs,
&child_file, true, &local_err);
if (local_err) {
goto fail;
}
+ if (file != NULL) {
+ qdict_put(options, "file",
+ qstring_from_str(bdrv_get_node_name(file->bs)));
+ }
}
/* Image format probing */
@@ -1835,7 +1844,7 @@ static BlockDriverState *bdrv_open_inherit(const char *filename,
goto fail;
}
- if (file && (bs->file != file)) {
+ if (file) {
bdrv_unref_child(bs, file);
file = NULL;
}
@@ -1901,6 +1910,9 @@ fail:
if (file != NULL) {
bdrv_unref_child(bs, file);
}
+ if (bs->file != NULL) {
+ bdrv_unref_child(bs, bs->file);
+ }
QDECREF(snapshot_options);
QDECREF(bs->explicit_options);
QDECREF(bs->options);
diff --git a/block/bochs.c b/block/bochs.c
index 8c9652e..7dd2ac4 100644
--- a/block/bochs.c
+++ b/block/bochs.c
@@ -104,6 +104,12 @@ static int bochs_open(BlockDriverState *bs, QDict *options, int flags,
struct bochs_header bochs;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->read_only = true; /* no write support yet */
ret = bdrv_pread(bs->file, 0, &bochs, sizeof(bochs));
diff --git a/block/cloop.c b/block/cloop.c
index 7b75f7e..877c9b0 100644
--- a/block/cloop.c
+++ b/block/cloop.c
@@ -66,6 +66,12 @@ static int cloop_open(BlockDriverState *bs, QDict *options, int flags,
uint32_t offsets_size, max_compressed_block_size = 1, i;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->read_only = true;
/* read header */
diff --git a/block/crypto.c b/block/crypto.c
index 7aa7eb5..200fd0b 100644
--- a/block/crypto.c
+++ b/block/crypto.c
@@ -300,6 +300,12 @@ static int block_crypto_open_generic(QCryptoBlockFormat format,
QCryptoBlockOpenOptions *open_opts = NULL;
unsigned int cflags = 0;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
opts = qemu_opts_create(opts_spec, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
diff --git a/block/dmg.c b/block/dmg.c
index 58a3ae8..8e387cd 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -413,6 +413,12 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
int64_t offset;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
block_module_load_one("dmg-bz2");
bs->read_only = true;
diff --git a/block/parallels.c b/block/parallels.c
index 2ccefa7..d3970e1 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -581,6 +581,12 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags,
Error *local_err = NULL;
char *buf;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = bdrv_pread(bs->file, 0, &ph, sizeof(ph));
if (ret < 0) {
goto fail;
diff --git a/block/qcow.c b/block/qcow.c
index fb738fc..a6dfe1a 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -106,6 +106,12 @@ static int qcow_open(BlockDriverState *bs, QDict *options, int flags,
QCowHeader header;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
if (ret < 0) {
goto fail;
diff --git a/block/qcow2.c b/block/qcow2.c
index 3e274bd..4684554 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -814,8 +814,8 @@ static int qcow2_update_options(BlockDriverState *bs, QDict *options,
return ret;
}
-static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
- Error **errp)
+static int qcow2_do_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
{
BDRVQcow2State *s = bs->opaque;
unsigned int len, i;
@@ -1205,6 +1205,18 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
return ret;
}
+static int qcow2_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
+ return qcow2_do_open(bs, options, flags, errp);
+}
+
static void qcow2_refresh_limits(BlockDriverState *bs, Error **errp)
{
BDRVQcow2State *s = bs->opaque;
@@ -1785,7 +1797,7 @@ static void qcow2_invalidate_cache(BlockDriverState *bs, Error **errp)
options = qdict_clone_shallow(bs->options);
flags &= ~BDRV_O_INACTIVE;
- ret = qcow2_open(bs, options, flags, &local_err);
+ ret = qcow2_do_open(bs, options, flags, &local_err);
QDECREF(options);
if (local_err) {
error_propagate(errp, local_err);
diff --git a/block/qed.c b/block/qed.c
index 1a7ef0a..1ea5114 100644
--- a/block/qed.c
+++ b/block/qed.c
@@ -391,8 +391,8 @@ static void bdrv_qed_drain(BlockDriverState *bs)
}
}
-static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
- Error **errp)
+static int bdrv_qed_do_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
{
BDRVQEDState *s = bs->opaque;
QEDHeader le_header;
@@ -526,6 +526,18 @@ out:
return ret;
}
+static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
+ return bdrv_qed_do_open(bs, options, flags, errp);
+}
+
static void bdrv_qed_refresh_limits(BlockDriverState *bs, Error **errp)
{
BDRVQEDState *s = bs->opaque;
@@ -1603,7 +1615,7 @@ static void bdrv_qed_invalidate_cache(BlockDriverState *bs, Error **errp)
bdrv_qed_close(bs);
memset(s, 0, sizeof(BDRVQEDState));
- ret = bdrv_qed_open(bs, NULL, bs->open_flags, &local_err);
+ ret = bdrv_qed_do_open(bs, NULL, bs->open_flags, &local_err);
if (local_err) {
error_propagate(errp, local_err);
error_prepend(errp, "Could not reopen qed layer: ");
diff --git a/block/raw-format.c b/block/raw-format.c
index 8404a82..30caaa5 100644
--- a/block/raw-format.c
+++ b/block/raw-format.c
@@ -384,6 +384,12 @@ static int raw_open(BlockDriverState *bs, QDict *options, int flags,
BDRVRawState *s = bs->opaque;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
bs->sg = bs->file->bs->sg;
bs->supported_write_flags = BDRV_REQ_FUA &
bs->file->bs->supported_write_flags;
diff --git a/block/replication.c b/block/replication.c
index 729dd12..eff85c7 100644
--- a/block/replication.c
+++ b/block/replication.c
@@ -86,6 +86,12 @@ static int replication_open(BlockDriverState *bs, QDict *options,
const char *mode;
const char *top_id;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
ret = -EINVAL;
opts = qemu_opts_create(&replication_runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
diff --git a/block/vdi.c b/block/vdi.c
index 0aeb940..18b4773 100644
--- a/block/vdi.c
+++ b/block/vdi.c
@@ -363,6 +363,12 @@ static int vdi_open(BlockDriverState *bs, QDict *options, int flags,
int ret;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
logout("\n");
ret = bdrv_read(bs->file, 0, (uint8_t *)&header, 1);
diff --git a/block/vhdx.c b/block/vhdx.c
index 68db9e0..4dc2743 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -898,6 +898,12 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags,
uint64_t signature;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
s->bat = NULL;
s->first_visible_write = true;
diff --git a/block/vmdk.c b/block/vmdk.c
index 393c84d..9d68ec5 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -943,6 +943,12 @@ static int vmdk_open(BlockDriverState *bs, QDict *options, int flags,
uint32_t magic;
Error *local_err = NULL;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
buf = vmdk_read_desc(bs->file, 0, errp);
if (!buf) {
return -EINVAL;
diff --git a/block/vpc.c b/block/vpc.c
index ed6353d..d0df2a1 100644
--- a/block/vpc.c
+++ b/block/vpc.c
@@ -220,6 +220,12 @@ static int vpc_open(BlockDriverState *bs, QDict *options, int flags,
int disk_type = VHD_DYNAMIC;
int ret;
+ bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
+ false, errp);
+ if (!bs->file) {
+ return -EINVAL;
+ }
+
opts = qemu_opts_create(&vpc_runtime_opts, NULL, 0, &error_abort);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (local_err) {
diff --git a/tests/qemu-iotests/051.out b/tests/qemu-iotests/051.out
index 42bf416..7524c62 100644
--- a/tests/qemu-iotests/051.out
+++ b/tests/qemu-iotests/051.out
@@ -225,7 +225,7 @@ Testing: -drive driver=nbd
QEMU_PROG: -drive driver=nbd: NBD server address missing
Testing: -drive driver=raw
-QEMU_PROG: -drive driver=raw: Can't use 'raw' as a block driver for the protocol level
+QEMU_PROG: -drive driver=raw: A block device must be specified for "file"
Testing: -drive file.driver=file
QEMU_PROG: -drive file.driver=file: The 'file' block driver requires a file name
@@ -234,7 +234,7 @@ Testing: -drive file.driver=nbd
QEMU_PROG: -drive file.driver=nbd: NBD server address missing
Testing: -drive file.driver=raw
-QEMU_PROG: -drive file.driver=raw: Can't use 'raw' as a block driver for the protocol level
+QEMU_PROG: -drive file.driver=raw: A block device must be specified for "file"
Testing: -drive foo=bar
QEMU_PROG: -drive foo=bar: Must specify either driver or file
diff --git a/tests/qemu-iotests/051.pc.out b/tests/qemu-iotests/051.pc.out
index 603bb76..f1669c1 100644
--- a/tests/qemu-iotests/051.pc.out
+++ b/tests/qemu-iotests/051.pc.out
@@ -319,7 +319,7 @@ Testing: -drive driver=nbd
QEMU_PROG: -drive driver=nbd: NBD server address missing
Testing: -drive driver=raw
-QEMU_PROG: -drive driver=raw: Can't use 'raw' as a block driver for the protocol level
+QEMU_PROG: -drive driver=raw: A block device must be specified for "file"
Testing: -drive file.driver=file
QEMU_PROG: -drive file.driver=file: The 'file' block driver requires a file name
@@ -328,7 +328,7 @@ Testing: -drive file.driver=nbd
QEMU_PROG: -drive file.driver=nbd: NBD server address missing
Testing: -drive file.driver=raw
-QEMU_PROG: -drive file.driver=raw: Can't use 'raw' as a block driver for the protocol level
+QEMU_PROG: -drive file.driver=raw: A block device must be specified for "file"
Testing: -drive foo=bar
QEMU_PROG: -drive foo=bar: Must specify either driver or file
--
1.8.3.1