Commit Graph

1067 Commits

Author SHA1 Message Date
Max Reitz
7454d60045 qcow2: Don't shadow return value
When trying to update the refcounts for a snapshot, the return value of
update_refcount on a compressed cluster was pretty much ignored,
cancelling the update on error but returning 0. This is caused by an
inner "ret" variable shadowing the outer one (the latter is used in the
return statement).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-25 10:08:56 +02:00
Anthony Liguori
16121fa39e Merge remote-tracking branch 'stefanha/block' into staging
# By Stefan Hajnoczi (4) and others
# Via Stefan Hajnoczi
* stefanha/block:
  virtio-blk: do not relay a previous driver's WCE configuration to the current
  blockdev: do not default cache.no-flush to true
  block: don't lose data from last incomplete sector
  qcow2: Correct snapshots size for overlap check
  coroutine: fix /perf/nesting coroutine benchmark
  coroutine: add qemu_coroutine_yield benchmark
  qemu-timer: do not take the lock in timer_pending
  qemu-timer: make qemu_timer_mod_ns() and qemu_timer_del() thread-safe
  qemu-timer: drop outdated signal safety comments
  osdep: warn if open(O_DIRECT) on fails with EINVAL
  libcacard: link against qemu-error.o for error_report()

Message-id: 1379698931-946-1-git-send-email-stefanha@redhat.com
2013-09-23 11:53:05 -05:00
Anthony Liguori
f3ca508f00 Merge remote-tracking branch 'bonzini/scsi-next' into staging
# By Hervé Poussineau (5) and Stefan Weil (1)
# Via Paolo Bonzini
* bonzini/scsi-next:
  block/iscsi: Drop iscsi_co_get_block_status for older versions of libiscsi
  lsi: add 53C810 variant
  lsi: remove todo
  lsi: ignore write accesses to CTEST0 registers
  lsi: check ssid versus sdid only if ssid is valid
  lsi: use constant name instead of its value
2013-09-23 11:52:32 -05:00
Max Reitz
0f39ac9a07 qcow2: Correct snapshots size for overlap check
Using s->snapshots_size instead of snapshots_size for the metadata
overlap check in qcow2_write_snapshots leads to the detection of an
overlap with the main qcow2 image header when deleting the last
snapshot, since s->snapshots_size has not yet been updated and is
therefore non-zero. However, the offset returned by qcow2_alloc_clusters
will be zero since snapshots_size is zero. Therefore, an overlap is
detected albeit no such will occur.

This patch fixes this by replacing s->snapshots_size by snapshots_size
when calling qcow2_pre_write_overlap_check.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-20 12:48:03 +02:00
Stefan Weil
f35c934a5a block/iscsi: Drop iscsi_co_get_block_status for older versions of libiscsi
Debian wheezy includes libiscsi-dev 1.4.0 which does not provide
SCSI_PROVISIONING_TYPE_DEALLOCATED. Drop iscsi_co_get_block_status
in this case to allow compilation without errors.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-18 01:28:50 +02:00
Anthony Liguori
5dc11192b2 Merge remote-tracking branch 'kwolf/for-anthony' into staging
# By Max Reitz (16) and others
# Via Kevin Wolf
* kwolf/for-anthony: (33 commits)
  qemu-iotests: Fix test 038
  block: Assert validity of BdrvActionOps
  qemu-iotests: Cleanup test image in test number 007
  qemu-img: fix invalid JSON
  coroutine: add ./configure --disable-coroutine-pool
  qemu-iotests: Adjustments due to error propagation
  qcow2: Use Error parameter
  qemu-img create: Emit filename on error
  block: Error parameter for create functions
  block: Error parameter for open functions
  bdrv: Use "Error" for creating images
  bdrv: Use "Error" for opening images
  qemu-iotests: add 057 internal snapshot for block device test case
  hmp: add interface hmp_snapshot_delete_blkdev_internal
  hmp: add interface hmp_snapshot_blkdev_internal
  qmp: add interface blockdev-snapshot-delete-internal-sync
  qmp: add interface blockdev-snapshot-internal-sync
  qmp: add internal snapshot support in qmp_transaction
  snapshot: distinguish id and name in snapshot delete
  snapshot: new function bdrv_snapshot_find_by_id_and_name()
  ...

Message-id: 1379073063-14963-1-git-send-email-kwolf@redhat.com
2013-09-17 09:51:40 -05:00
Peter Lieven
65f3e33964 iscsi: split discard requests in multiple parts
Replace .bdrv_aio_discard with .bdrv_co_discard so that discard
requests can be split in multiple parts, each for a small amount
of sectors.

This is useful because we expose a generic API with no limit
on the amount of sectors that can be unmapped in one request.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-12 13:14:19 +02:00
Max Reitz
3ef6c40ad0 qcow2: Use Error parameter
Employ usage of the new Error ** parameter in qcow2_open, qcow2_create
and associated functions.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:48 +02:00
Max Reitz
cc84d90ff5 block: Error parameter for create functions
Add an Error ** parameter to bdrv_create and its associated functions to
allow more specific error messages.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:48 +02:00
Max Reitz
34b5d2c68e block: Error parameter for open functions
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated
functions to allow more specific error messages.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:48 +02:00
Max Reitz
d5124c00d8 bdrv: Use "Error" for creating images
Add an Error ** parameter to BlockDriver.bdrv_create to allow more
specific error messages.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:48 +02:00
Max Reitz
015a1036a7 bdrv: Use "Error" for opening images
Add an Error ** parameter to BlockDriver.bdrv_open and
BlockDriver.bdrv_file_open to allow more specific error messages.

Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:47 +02:00
Wenchao Xia
a89d89d3e6 snapshot: distinguish id and name in snapshot delete
Snapshot creation actually already distinguish id and name since it take
a structured parameter *sn, but delete can't. Later an accurate delete
is needed in qmp_transaction abort and blockdev-snapshot-delete-sync,
so change its prototype. Also *errp is added to tip error, but return
value is kepted to let caller check what kind of error happens. Existing
caller for it are savevm, delvm and qemu-img, they are not impacted by
introducing a new function bdrv_snapshot_delete_by_id_or_name(), which
check the return value and do the operation again.

Before this patch:
  For qcow2, it search id first then name to find the one to delete.
  For rbd, it search name.
  For sheepdog, it does nothing.

After this patch:
  For qcow2, logic is the same by call it twice in caller.
  For rbd, it always fails in delete with id, but still search for name
in second try, no change to user.

Some code for *errp is based on Pavel's patch.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:47 +02:00
Wenchao Xia
2ea1dd758c snapshot: new function bdrv_snapshot_find_by_id_and_name()
To make it clear about id and name in searching, add this API
to distinguish them. Caller can choose to search by id or name,
*errp will be set only for exception.

Some code are modified based on Pavel's patch.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:47 +02:00
Max Reitz
9296b3ed70 qcow2: Implement bdrv_amend_options
Implement bdrv_amend_options for compat, size, backing_file, backing_fmt
and lazy_refcounts.

Downgrading images from compat=1.1 to compat=0.10 is achieved through
handling all incompatible flags accordingly, clearing all compatible and
autoclear flags and expanding all zero clusters.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:46 +02:00
Max Reitz
b6481f376b qcow2: Save refcount order in BDRVQcowState
Save the image refcount order in BDRVQcowState. This will be relevant
for future code supporting different refcount orders than four and also
for code that needs to verify a certain refcount order for an opened
image.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:46 +02:00
Max Reitz
32b6444d23 qcow2-cluster: Expand zero clusters
Add functionality for expanding zero clusters. This is necessary for
downgrading the image version to one without zero cluster support.

For non-backed images, this function may also just discard zero clusters
instead of truly expanding them.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:46 +02:00
Max Reitz
e7108feaac qcow2-cache: Empty cache
Add a function for emptying a cache, i.e., flushing it and marking all
elements invalid.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:46 +02:00
Tal Kain
56e023af80 raw-win32.c: Fix incorrect handling behaviour of small block files
It is a valid case that the read data's size is smaller than the
requested size since there could be files that are smaller than
the minimum block size (For ex. when a VMDK disk descriptor file)

Signed-off-by: Tal Kain <tal.kain@ravellosystems.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12 10:12:46 +02:00
Kevin Wolf
1ebf561c11 qcow2: Discard VM state in active L1 after creating snapshot
During savevm, the VM state is written to the active L1 of the image and
then a snapshot is taken. After that, the VM state isn't needed any more
in the active L1 and should be discarded. This is implemented by this
patch.

The impact of not discarding the VM state is that a snapshot can never
become smaller than any previous snapshot (because it would be padded
with old VM state), and more importantly that future savevm operations
cause unnecessary COWs (with associated flushes), which makes subsequent
snapshots much slower.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:46 +02:00
Kevin Wolf
670df5e3b4 qcow2: Pass discard type to qcow2_discard_clusters()
The function will be used internally instead of only being called for
guest discard requests.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2013-09-12 10:12:46 +02:00
Peter Lieven
54a5c1d5db iscsi: add .bdrv_get_block_status
this patch adds a coroutine for .bdrv_co_block_status as well as
a generic framework that can be used to build coroutines in block/iscsi.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-12 08:46:21 +02:00
Peter Lieven
f18a7cbb09 iscsi: add logical block provisioning information to iscsilun
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-12 08:46:21 +02:00
Paolo Bonzini
5accc8408f scsi: prefer UUID to VM name for the initiator name
The UUID is unique even across multiple hosts, thus it is
better than a VM name even if it is less user-friendly.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-12 08:46:21 +02:00
Paolo Bonzini
f5f7abcfd5 raw-posix: report unwritten extents as zero
These are created for example with XFS_IOC_ZERO_RANGE.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
63390a8d14 raw-posix: return get_block_status data and flags
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
4bc74be997 block: return get_block_status data and flags for formats
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
b6b8a33354 block: introduce bdrv_get_block_status API
For now, bdrv_get_block_status is just another name for bdrv_is_allocated.
The next patches will add more flags.

This also touches all block drivers with a mostly mechanical rename.  The
sole exception is cow; because it calls cow_co_is_allocated from the read
code, we keep that function and make cow_co_get_block_status a wrapper.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
d663640c04 block: expect errors from bdrv_co_is_allocated
Some bdrv_is_allocated callers do not expect errors, but the fallback
in qcow2.c might make other callers trip on assertion failures or
infinite loops.

Fix the callers to always look for errors.

Cc: qemu-stable@nongnu.org
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
4f5786376e block: remove bdrv_is_allocated_above/bdrv_co_is_allocated_above distinction
Now that bdrv_is_allocated detects coroutine context, the two can
use the same code.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:09 +02:00
Paolo Bonzini
bdad13b9de block: make bdrv_co_is_allocated static
bdrv_is_allocated can detect coroutine context and go through a fast
path, similar to other block layer functions.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Paolo Bonzini
e641c1e81e cow: do not call bdrv_co_is_allocated
As we change bdrv_is_allocated to gather more information from bs and
bs->file, it will become a bit slower.  It is still appropriate for online
jobs, but not for reads/writes.  Call the internal function instead.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Paolo Bonzini
26ae980492 cow: make writes go at a less indecent speed
Only sync once per write, rather than once per sector.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Paolo Bonzini
276cbc7f2f cow: make reads go at a decent speed
Do not do two reads for each sector; load each sector of the bitmap
and use bitmap operations to process it.

Writes are still dog slow!

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Fam Zheng
4f6fd3491c block: make bdrv_delete() static
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no
longer public and should be called by bdrv_unref() if refcnt is
decreased to 0.

This is an identical change because effectively, there's no multiple
reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets
bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Fam Zheng
13c91cb7e2 iscsi: use bdrv_new() instead of stack structure
BlockDriverState structure needs bdrv_new() to initialize refcnt, don't
allocate a local structure variable and memset to 0, becasue with coming
refcnt implementation, bdrv_unref will crash if bs->refcnt not
initialized to 1.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Fam Zheng
3d34c6cd99 vvfat: use bdrv_new() to allocate BlockDriverState
we need bdrv_new() to properly initialize BDS, don't allocate memory
manually.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Stefan Weil
68dc036488 w32: Fix access to host devices (regression)
QEMU failed to open host devices like \\.\PhysicalDrive0 (first hard disk)
since some time (commit 8a79380b8ef1b02d2abd705dd026a18863b09020?).

Those devices use hdev_open which did not use the latest API for options.
This resulted in a fatal runtime error:

  Block protocol 'host_device' doesn't support the option 'filename'

Duplicate code from raw_open to fix this.

Cc: qemu-stable@nongnu.org
Reported-by: David Brenner <david.brenner3@gmail.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Benoît Canet
2024c1df43 block: Add iops_size to do the iops accounting for a given io size.
This feature can be used in case where users are avoiding the iops limit by
doing jumbo I/Os hammering the storage backend.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Benoît Canet
3e9fab690d block: Add support for throttling burst max in QMP and the command line.
The max parameter of the leaky bucket throttling algorithm can be used to
allow the guest to do bursts.
The max value is a pool of I/O that the guest can use without being throttled
at all. Throttling is triggered once this pool is empty.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Benoît Canet
cc0681c454 block: Enable the new throttling code in the block layer.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:07 +02:00
Anthony Liguori
bb7d4d82b6 Merge remote-tracking branch 'kwolf/for-anthony' into staging
# By Max Reitz (11) and others
# Via Kevin Wolf
* kwolf/for-anthony: (26 commits)
  qemu-iotests: Overlapping cluster allocations
  qcow2_check: Mark image consistent
  qcow2-refcount: Repair shared refcount blocks
  qcow2-refcount: Repair OFLAG_COPIED errors
  qcow2-refcount: Move OFLAG_COPIED checks
  qcow2: Employ metadata overlap checks
  qcow2: Metadata overlap checks
  qcow2: Add corrupt bit
  qemu-iotests: Snapshotting zero clusters
  qcow2-refcount: Snapshot update for zero clusters
  option: Add assigned flag to QEMUOptionParameter
  gluster: Abort on AIO completion failure
  block: Remove old raw driver
  switch raw block driver from "raw.o" to "raw_bsd.o"
  raw_bsd: register bdrv_raw
  raw_bsd: add raw_create_options
  raw_bsd: introduce "special members"
  raw_bsd: add raw_create()
  raw_bsd: emit debug events in bdrv_co_readv() and bdrv_co_writev()
  add skeleton for BSD licensed "raw" BlockDriver
  ...

Message-id: 1378111792-20436-1-git-send-email-kwolf@redhat.com
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>
2013-09-03 12:32:46 -05:00
Max Reitz
24530f3e06 qcow2_check: Mark image consistent
If no corruptions remain after an image repair (and no errors have been
encountered), clear the corrupt flag in qcow2_check.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-02 10:15:15 +02:00
Max Reitz
afa50193cd qcow2-refcount: Repair shared refcount blocks
If the refcount of a refcount block is greater than one, we can at least
try to repair that problem by duplicating the affected block.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-02 10:06:59 +02:00
Stefan Hajnoczi
5b21a2ae4d curl: qemu_bh_new() can never return NULL
Drop error code path which cannot be taken since qemu_bh_new() does not
return NULL.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-09-01 19:11:56 +04:00
Stefan Weil
4c293dc6e4 misc: Fix some typos in names and comments
Most typos were found using a modified version of codespell:

accross -> across
issueing -> issuing
TICNT_THRESHHOLD -> TICNT_THRESHOLD
bandwith -> bandwidth
VCARD_7816_PROPIETARY -> VCARD_7816_PROPRIETARY
occured -> occurred
gaurantee -> guarantee
sofware -> software

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-09-01 18:59:24 +04:00
Max Reitz
e23e400ec6 qcow2-refcount: Repair OFLAG_COPIED errors
Since the OFLAG_COPIED checks are now executed after the refcounts have
been repaired (if repairing), it is safe to assume that they are correct
but the OFLAG_COPIED flag may be not. Therefore, if its value differs
from what it should be (considering the according refcount), that
discrepancy can be repaired by correctly setting (or clearing that flag.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:48:44 +02:00
Max Reitz
4f6ed88c03 qcow2-refcount: Move OFLAG_COPIED checks
Move the OFLAG_COPIED checks out of check_refcounts_l1 and
check_refcounts_l2 and after the actual refcount checks/fixes (since the
refcounts might actually change there).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:48:44 +02:00
Max Reitz
cf93980e77 qcow2: Employ metadata overlap checks
The pre-write overlap check function is now called before most of the
qcow2 writes (aborting it on collision or other error).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:48:43 +02:00
Max Reitz
a40f1c2add qcow2: Metadata overlap checks
Two new functions are added; the first one checks a given range in the
image file for overlaps with metadata (main header, L1 tables, L2
tables, refcount table and blocks).

The second one should be used immediately before writing to the image
file as it calls the first function and, upon collision, marks the
image as corrupt and makes the BDS unusable, thereby preventing
further access.

Both functions take a bitmask argument specifying the structures which
should be checked for overlaps, making it possible to also check
metadata writes against colliding with other structures.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:48:43 +02:00