Commit Graph

211 Commits

Author SHA1 Message Date
Max Reitz ddf5636dc9 block: Add reference parameter to bdrv_open()
Allow bdrv_open() to handle references to existing block devices just as
bdrv_file_open() is already capable of.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:22 +01:00
Max Reitz f67503e5bd block: Change BDS parameter of bdrv_open() to **
Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:21 +01:00
Markus Armbruster 84d18f065f Use error_is_set() only when necessary
error_is_set(&var) is the same as var != NULL, but it takes
whole-program analysis to figure that out.  Unnecessarily hard for
optimizers, static checkers, and human readers.  Dumb it down to
obvious.

Gets rid of several dozen Coverity false positives.

Note that the obvious form is already used in many places.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-17 11:57:23 -05:00
Hu Tao 7c2bbf4aa6 qcow2: check for NULL l2meta
In the case of a metadata preallocation with a large cluster size,
qcow2_alloc_cluster_offset() can allocate nothing and returns a
NULL l2meta. This patch checks for it and link2 l2 with only valid
l2meta.

Replace 9 and 512 with BDRV_SECTOR_BITS, BDRV_SECTOR_SIZE
respectively while at the function.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-09 09:12:39 +01:00
Hu Tao 16f0587e0a qcow2: remove n_start and n_end of qcow2_alloc_cluster_offset()
n_start can be actually calculated from offset. The number of
sectors to be allocated(n_end - n_start) can be passed in in
num. By removing n_start and n_end, we can save two parameters.

The side effect is there is a bug in qcow2.c:preallocate() that
passes incorrect n_start to qcow2_alloc_cluster_offset() is
fixed. The bug can be triggerred by a larger cluster size than
the default value(65536), for example:

./qemu-img create -f qcow2 \
  -o 'cluster_size=131072,preallocation=metadata' file.img 4G

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-09 09:12:39 +01:00
Jeff Cody 14b4a8b9c6 block: remove qcow2 .bdrv_make_empty implementation
The QCOW2 .bdrv_make_empty implementation always returns 0 for success,
but does not actually do anything.

The proper way to not support an optional driver function stub is to
just not implement it, so let's remove the stub.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-01-31 22:05:03 +01:00
Kevin Wolf d34682cd4a block: Move initialisation of BlockLimits to bdrv_refresh_limits()
This function separates filling the BlockLimits from bdrv_open(), which
allows it to call it from other operations which may change the limits
(e.g. modifications to the backing file chain or bdrv_reopen)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24 17:40:01 +01:00
Max Reitz 72daa72eee block: Allow reference for bdrv_file_open()
Allow specifying a reference to an existing block device (by name) for
bdrv_file_open() instead of a filename and/or options.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-22 12:07:17 +01:00
Peter Crosthwaite 87ea75d5e1 qemu-option: Remove qemu_opts_create_nofail
This is a boiler-plate _nofail variant of qemu_opts_create. Remove and
use error_abort in call sites.

null/0 arguments needs to be added for the id and fail_if_exists fields
in affected callsites due to argument inconsistency between the normal and
no_fail variants.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-01-06 15:02:30 -05:00
Kevin Wolf f8413b3c23 qcow2: Zero-initialise first cluster for new images
Strictly speaking, this is only required for has_zero_init() == false,
but it's easy enough to just do a cluster-aligned write that is padded
with zeros after the header.

This fixes that after 'qemu-img create' header extensions are attempted
to be parsed that are really just random leftover data.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-04 11:29:37 +01:00
Paolo Bonzini cffb1ec600 block drivers: expose requirement for write same alignment from formats
This will let misaligned but large requests use zero clusters.  This
is important because the cluster size is not guest visible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-03 15:26:49 +01:00
Paolo Bonzini 95de6d7078 block drivers: add discard/write_zeroes properties to bdrv_get_info implementation
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-03 15:26:49 +01:00
Kevin Wolf c9fbb99d41 block: Use BDRV_O_NO_BACKING where appropriate
If you open an image temporarily just because you want to check its size
or get it flushed, there's no real reason to open the whole backing file
chain.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2013-11-29 17:41:09 +01:00
Peter Lieven aa7bfbfff7 block: add flags to bdrv_*_write_zeroes
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28 10:30:51 +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
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
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 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 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
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
Jeff Cody c4217f645d block: qcow2 - used QEMU_PACKED for on-disk structures
QCowHeader and QCowExtension are structs that reside in the on-disk
image format, and are read and written directly via bdrv_pread()/write(),
and as such should be packed to avoid any unintentional struct padding.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-25 20:51:13 +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
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
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
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
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
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 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 69c9872653 qcow2: Add corrupt bit
This adds an incompatible bit indicating corruption to qcow2. Any image
with this bit set may not be written to unless for repairing (and
subsequently clearing the bit if the repair has been successful).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-30 15:48:43 +02:00
Kevin Wolf 9117b47717 qcow2: Change default for new images to compat=1.1
By the time that qemu 1.7 will be released, enough time will have passed
since qemu 1.1, which is the first version to understand version 3
images, that changing the default shouldn't hurt many people any more
and the benefits of using the new format outweigh the pain.

qemu-iotests already runs with compat=1.1 by default.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-08-30 15:28:51 +02:00
Asias He 0d51b4debe block: Introduce bs->zero_beyond_eof
In 4146b46c42e0989cb5842e04d88ab6ccb1713a48 (block: Produce zeros when
protocols reading beyond end of file), we break qemu-iotests ./check
-qcow2 022. This happens because qcow2 temporarily sets ->growable = 1
for vmstate accesses (which are stored beyond the end of regular image
data).

We introduce the bs->zero_beyond_eof to allow qcow2_load_vmstate() to
disable ->zero_beyond_eof temporarily in addition to enable ->growable.

[Since the broken patch "block: Produce zeros when protocols reading
beyond end of file" has not been merged yet, I have applied this fix
*first* and will then apply the next patch to keep the tree bisectable.
-- Stefan]

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 14:10:21 +02:00
Kevin Wolf 8ad1898cf1 qcow2: Change default for new images to compat=1.1
By the time that qemu 1.7 will be released, enough time will have passed
since qemu 1.1, which is the first version to understand version 3
images, that changing the default shouldn't hurt many people any more
and the benefits of using the new format outweigh the pain.

qemu-iotests already runs with compat=1.1 by default.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-21 14:41:09 +02:00
Kevin Wolf 64aa99d3e0 qcow2: Use dashes instead of underscores in options
This is what QMP wants to use. The options haven't been enabled in any
release yet, so we're still free to change them.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 21:59:56 +02:00
Peter Lieven 3ac216270a block: change default of .has_zero_init to 0
.has_zero_init defaults to 1 for all formats and protocols.

this is a dangerous default since this means that all
new added drivers need to manually overwrite it to 0 if
they do not ensure that a device is zero initialized
after bdrv_create().

if a driver needs to explicitly set this value to
1 its easier to verify the correctness in the review process.

during review of the existing drivers it turned out
that ssh and gluster had a wrong default of 1.
both protocols support host_devices as backend
which are not by default zero initialized. this
wrong assumption will lead to possible corruption
if qemu-img convert is used to write to such a backend.

vpc and vmdk also defaulted to 1 altough they support
fixed respectively flat extends. this has to be addresses
in separate patches. both formats as well as the mentioned
ssh and gluster are turned to the default of 0 with this
patch for safety.

a similar problem with the wrong default existed for
iscsi most likely because the driver developer did
oversee the default value of 1.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 13:52:35 +02:00
Kevin Wolf 0b919fae31 qcow2: Batch discards
This optimises the discard operation for freed clusters by batching
discard requests (both snapshot deletion and bdrv_discard end up
updating the refcounts cluster by cluster).

Note that we don't discard asynchronously, but keep s->lock held. This
is to avoid that a freed cluster is reallocated and written to while the
discard is still in flight.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-06-24 10:25:17 +02:00
Kevin Wolf 67af674e47 qcow2: Options to enable discard for freed clusters
Deleted snapshots are discarded in the image file by default, discard
requests take their default from the -drive discard=... option and other
places that free clusters must always be enabled explicitly.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-06-24 10:25:17 +02:00
Kevin Wolf 6cfcb9b8b9 qcow2: Add refcount update reason to all callers
This adds a refcount update reason to all callers of update_refcounts(),
so that a follow-up patch can use this information to decide whether
clusters that reach a refcount of 0 should be discarded in the image
file.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-06-24 10:25:17 +02:00