Commit Graph

1136 Commits

Author SHA1 Message Date
MORITA Kazutaka
35200687a1 sheepdog: cancel aio requests if possible
This patch tries to cancel aio requests in pending queue and failed
queue.  When the sheepdog driver cannot cancel the requests, it waits
for them to be completed.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:22:20 +01:00
MORITA Kazutaka
a37dcdf9ae sheepdog: make add_aio_request and send_aioreq void functions
These functions no longer return errors.  We can make them void
functions and simplify the codes.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:22:15 +01:00
MORITA Kazutaka
011603cacf sheepdog: try to reconnect to sheepdog after network error
This introduces a failed request queue and links all the inflight
requests to the list after network error happens.  After QEMU
reconnects to the sheepdog server successfully, the sheepdog block
driver will retry all the requests in the failed queue.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:22:12 +01:00
MORITA Kazutaka
72e0996c41 sheepdog: reload inode outside of resend_aioreq
This prepares for using resend_aioreq() after reconnecting to the
sheepdog server.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:22:05 +01:00
MORITA Kazutaka
2412aec745 sheepdog: handle vdi objects in resend_aio_req
The current resend_aio_req() doesn't work when the request is against
vdi objects.  This fixes the problem.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:22:01 +01:00
MORITA Kazutaka
80731d9da5 sheepdog: check return values of qemu_co_recv/send correctly
If qemu_co_recv/send doesn't return the specified length, it means
that an error happened.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Tested-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-30 12:21:44 +01:00
Kevin Wolf
b94a261057 block: Avoid unecessary drv->bdrv_getlength() calls
The block layer generally keeps the size of an image cached in
bs->total_sectors so that it doesn't have to perform expensive
operations to get the size whenever it needs it.

This doesn't work however when using a backend that can change its size
without qemu being aware of it, i.e. passthrough of removable media like
CD-ROMs or floppy disks. For this reason, the caching is disabled when a
removable device is used.

It is obvious that checking whether the _guest_ device has removable
media isn't the right thing to do when we want to know whether the size
of the host backend can change. To make things worse, non-top-level
BlockDriverStates never have any device attached, which makes qemu
assume they are removable, so drv->bdrv_getlength() is always called on
the protocol layer. In the case of raw-posix, this causes unnecessary
lseek() system calls, which turned out to be rather expensive.

This patch completely changes the logic and disables bs->total_sectors
caching only for certain block driver types, for which a size change is
expected: host_cdrom and host_floppy on POSIX, host_device on win32; also
the raw format in case it sits on top of one of these protocols, but in
the common case the nested bdrv_getlength() call on the protocol driver
will use the cache again and avoid an expensive drv->bdrv_getlength()
call.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-29 13:10:26 +01:00
Liu Yuan
1841f8801c sheepdog: pass copy_policy in the request
Currently copy_policy isn't used. Recent sheepdog supports erasure coding, which
make use of copy_policy internally, but require client explicitly passing
copy_policy from base inode to newly creately inode for snapshot related
operations.

If connected sheep daemon doesn't utilize copy_policy, passing it to sheep
daemon is just one extra null effect operation. So no compatibility problem.

With this patch, sheepdog can provide erasure coded volume for QEMU VM.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Acked-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-28 17:40:00 +01:00
Liu Yuan
29a67f7e92 sheepdog: explicitly set copies as type uint8_t
'copies' is actually uint8_t since day one, but request headers and some helper
functions parameterize it as uint32_t for unknown reasons and effectively
reserve 24 bytes for possible future use. This patch explicitly set the correct
for copies and reserve the left bytes.

This is a preparation patch that allow passing copy_policy in request header.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Acked-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-28 17:39:56 +01:00
Max Reitz
ba2ab2f2ca qcow2: Flush image after creation
Opening the qcow2 image with BDRV_O_NO_FLUSH prevents any flushes during
the image creation. This means that the image has not yet been flushed
to disk when qemu-img create exits. This flush is delayed until the next
operation on the image involving opening it without BDRV_O_NO_FLUSH and
closing (or directly flushing) it. For large images and/or images with a
small cluster size and preallocated metadata, this flush may take a
significant amount of time and may occur unexpectedly.

Reopening the image without BDRV_O_NO_FLUSH right before the end of
qcow2_create2() results in hoisting the potentially costly flush into
the image creation, which is expected to take some time (whereas
successive image operations may be not).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-28 17:34:32 +01:00
Peter Lieven
fb8fe35f63 block/vpc: check that the image has not been truncated
this adds a check that a dynamic VHD file has not been
accidently truncated (e.g. during transfer or upload).

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-24 17:34:48 +02:00
Max Reitz
6e13610aa4 qcow2: Unset zero_beyond_eof in save_vmstate
Saving the VM state is done using bdrv_pwrite. This function may perform
a read-modify-write, which in this case results in data being read from
beyond the end of the virtual disk. Since we are actually trying to
access an area which is not a part of the virtual disk, zero_beyond_eof
has to be set to false before performing the partial write, otherwise
the VM state may become corrupted.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-24 11:50:51 +02:00
Max Reitz
eedff66f21 qcow2: Restore total_sectors value in save_vmstate
Since df2a6f29a5, bdrv_co_do_writev increases the total_sectors value of
a growable block devices on writes after the current end. This leads to
the virtual disk apparently growing in qcow2_save_vmstate, which in turn
affects the disk size captured by the internal snapshot taken directly
afterwards through e.g. the HMP savevm command. Such a "grown" snapshot
cannot be loaded after reopening the qcow2 image, since its disk size
differs from the actual virtual disk size (writing a VM state does not
actually increase the virtual disk size).

Fix this by restoring total_sectors at the end of qcow2_save_vmstate.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-24 11:45:06 +02:00
Fam Zheng
dbbcaa8d43 vmdk: fix VMFS extent parsing
The VMFS extent line in description file doesn't have start offset as
FLAT lines does, and it should be defaulted to 0. The flat_offset
variable is initialized to -1, so we need to set it in this case.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-18 13:41:36 +02:00
Fam Zheng
c338b6ad60 vmdk: Only read cid from image file when opening
Previously cid of parent is parsed from image file for every IO request.
We already have L1/L2 cache and don't have assumption that parent image
can be updated behind us, so remove this to get more efficiency.

The parent CID is checked only for once after opening.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-18 13:39:59 +02:00
Max Reitz
45d57f6e71 block/raw-win32: Always use -errno in hdev_open
On one occasion, hdev_open() returned -1 in case of an unknown error
instead of a proper -errno value. Adjust this to match the behavior of
raw_open() (in raw-win32), which is to return -EINVAL in this case.
Also, change the call to error_setg*() to match the one in raw_open() as
well.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-17 14:55:46 +02:00
Fam Zheng
899f1ae219 vmdk: Fix vmdk_parse_extents
An extra 'p++' after while loop when *p == '\n' will move p to unknown
data position, risking parsing junk data or memory access violation.

Cc: qemu-stable@nongnu.org
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:02 +02:00
Fam Zheng
52c8d629ca vmdk: refuse enabling zeroed grain with flat images
This is a header flag and we needs sparse for the header.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:01 +02:00
Fam Zheng
4823970bcb vmdk: convert error code to use errp
Convert "fprintf(stderr,..." and standardize error messages:

Remove a few local_error's and use errp.

Remove "VMDK:" or "Vmdk:" prefixes in error message and fix to upper
case.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:01 +02:00
Max Reitz
e428e439df block/raw-posix: Employ error parameter
Make use of the error parameter in the opening and creating functions in
block/raw-posix.c.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
ca2884087a blkverify: Employ error parameter
Make use of the error parameter in blkverify_open.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
10ffa72fae blkdebug: Employ error parameter
Make use of the error parameter in blkdebug_open.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
c6252b7cea block/raw-win32: Employ error parameter
Make use of the error parameter in the opening and creating functions in
block/raw-win32.c.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
92f1deec31 block/raw_bsd: Employ error parameter
Propagate errors in raw_create rather than directly reporting and
afterwards discarding them.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
1fa5cc839a qcow2: Evaluate overlap check options
Evaluate the runtime overlap check options and set
BDRVQcowState.overlap_check appropriately.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
4a273c398b qcow2: Add more overlap check bitmask macros
Introduces the macros QCOW2_OL_CONSTANT and QCOW2_OL_ALL in addition to
the already existing QCOW2_OL_CACHED, signifying all metadata overlap
checks that can be performed in constant time (regardless of image size
etc.) and truly all available overlap checks, respectively.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
4092e99d93 qcow2: Array assigning options to OL check bits
Add an array which assigns the option string to its corresponding
overlap check bit.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
05de7e86ca qcow2: Add overlap-check options
Add runtime options to tune the overlap checks to be performed before
write accesses.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
3e3553905c qcow2: Make overlap check mask variable
Replace the QCOW2_OL_DEFAULT macro by a variable overlap_check in
BDRVQcowState.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
231bb26764 qcow2: Use negated overflow check mask
In qcow2_check_metadata_overlap and qcow2_pre_write_overlap_check,
change the parameter signifying the checks to perform from its current
positive form to a negative one, i.e., it will no longer explicitly
specify every check to perform but rather a mask of checks not to
perform.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
00c49b21e7 qcow2: Use better type for numerical snapshot ID
When trying to find a new snapshot ID, the existing ones are converted
to integers using strtoul. This function returns an unsigned long,
therefore its result should be saved in an unsigned long as well.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
84757f7e67 qcow2: Fix snapshot restoration in snapshot_create
If the new snapshot table could not be written in qcow2_snapshot_create,
the old snapshot table has to be restored in memory and the new one
released. This should include restoration of the old snapshot count as
well, which is added by this patch.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz
f9bff97143 qcow2: Remove wrong metadata overlap check
In qcow2_write_compressed, if the compression fails, a normal cluster is
written to disk. This is done through bdrv_write on the qcow2 BDS
itself (using the guest offset), thus it is wrong to do a metadata
overlap check before.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
9e3f08923a qcow2: Add missing space in error message
The error message in qcow2_downgrade about an unsupported refcount
order is missing a space. This patch adds it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Benoît Canet
f6186f49e2 block: Add BlockDriver.bdrv_check_ext_snapshot.
This field is used by blkverify to disable external snapshots creation.
It will also be used by block filters like quorum to disable external
snapshot creation.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Peter Lieven
92bc50a5ad block/get_block_status: avoid redundant callouts on raw devices
if a raw device like an iscsi target or host device is used
the current implementation makes a second call out to get
the block status of bs->file.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
88fb153512 qcow2: Assert against snapshot name/ID overflow
qcow2_write_snapshots relies on the length of every snapshot ID and name
fitting into an unsigned 16 bit integer. This is currently ensured by
QEMU through generally only allowing 128 byte IDs and 256 byte names.
However, if this should change in the future, the length written to the
image file should not be silently truncated (though the name itself
would be written completely).

Since this is currently not an issue but might require attention due to
internal QEMU changes in the future, an assert ensuring sanity is enough
for now.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
9186ad9658 qcow2: Free allocated snapshot table on error
If an error occurs during qcow2_write_snapshots, the newly allocated
snapshot table clusters are leaked and should thus be freed.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
37d41f0a04 qcow2: Always use error path on writing snapshots
qcow2_write_snapshots does contain a fail label and there is no reason
not to use it on some errors; therefore, we should always jump there on
error.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
8f730dd24e qcow2: Free preallocated zero clusters
In qcow2_free_any_clusters, preallocated zero clusters should be freed
just as normal clusters are.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
998b959c1e qcow2: Use pread for inactive L1 in overlap check
Currently, qcow2_check_metadata_overlap uses bdrv_read to read inactive
L1 tables from disk. The number of sectors to read is calculated through
a truncating integer division, therefore, if the L1 table size is not a
multiple of the sector size, the final entries will not be read and
their entries in memory remain undefined (from the g_malloc).
Using bdrv_pread fixes this.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00
Max Reitz
37764dfb71 qcow2: Add support for ImageInfoSpecific
Add a new ImageInfoSpecificQCow2 type as a subtype of ImageInfoSpecific.
This contains the compatibility level as a string and an optional
lazy_refcounts boolean (optional means mandatory for compat >= 1.1 and
not available for compat == 0.10).

Also, add qcow2_get_specific_info, which returns this information.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 14:03:57 +02:00
Max Reitz
a8d8ecb77f block/qapi: Human-readable ImageInfoSpecific dump
Add a function for generically dumping the ImageInfoSpecific information
in a human-readable format to block/qapi.c.

Use this function in bdrv_image_info_dump and qemu-io-cmds.c:info_f to
allow qemu-img info resp. qemu-io -c info to print that format specific
information.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Max Reitz
eae041fe6f block: Add bdrv_get_specific_info
Add a function for retrieving an ImageInfoSpecific object from a block
driver.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Fam Zheng
79e14bf778 qapi: make use of new BlockJobType
Switch the string to enum type BlockJobType in BlockJobDriver.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Fam Zheng
3fc4b10af0 blockjob: rename BlockJobType to BlockJobDriver
We will use BlockJobType as the enum type name of block jobs in QAPI,
rename current BlockJobType to BlockJobDriver, which will eventually
become a set of operations, similar to block drivers.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Anthony Liguori
634ebf4b17 Merge remote-tracking branch 'bonzini/scsi-next' into staging
# By Asias He (1) and Peter Lieven (1)
# Via Paolo Bonzini
* bonzini/scsi-next:
  scsi: Allocate SCSITargetReq r->buf dynamically [CVE-2013-4344]
  block/iscsi: reenable iscsi_co_get_block_status

Message-id: 1381332391-8781-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@amazon.com>
2013-10-10 10:03:00 -07:00
Peter Lieven
24c7608a5d block/iscsi: reenable iscsi_co_get_block_status
Commit f35c934a accidently disabled iscsi_co_get_block_status for all
libiscsi versions. Its not possible to check for enumeration constants
in the C preprocessor. This patch changes the check to the preprocessor
constant LIBISCSI_FEATURE_IOVECTOR which was introduced shortly after
get_lba_status support was added to libiscsi.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-09 10:43:42 +02:00
Max Reitz
e3b21ef9e0 qcow2: Free allocated L2 cluster on error
If an error occurs in l2_allocate, the allocated (but unused) L2 cluster
should be freed.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-07 13:23:19 +02:00
Max Reitz
fda74f826b qcow2: Switch L1 table in a single sequence
Switching the L1 table in memory should be an atomic operation, as far
as possible. Calling qcow2_free_clusters on the old L1 table on disk is
not a good idea when the old L1 table is no longer valid and the address
to the new one hasn't yet been written into the corresponding
BDRVQcowState field. To be more specific, this can lead to segfaults due
to qcow2_check_metadata_overlap trying to access the L1 table during the
free operation.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-10-02 15:38:29 +02:00