Commit Graph

68 Commits

Author SHA1 Message Date
Alberto Garcia
81e5f78a9f block: use bdrv_get_device_or_node_name() in error messages
There are several error messages that identify a BlockDriverState by
its device name. However those errors can be produced in nodes that
don't have a device name associated.

In those cases we should use bdrv_get_device_or_node_name() to fall
back to the node name and produce a more meaningful message. The
messages are also updated to use the more generic term 'node' instead
of 'device'.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 9823a1f0514fdb0692e92868661c38a9e00a12d6.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Peter Lieven
304ee9174f block/vpc: remove disabled code from get_sector_offset
The code to check the bitmap for the allocation status of each sector
has been "disabled by reason" ever since the vpc driver existed.

The reason might be that we might end up reading sector by sector
in vpc_read if we really used it. This would be a performance desaster.

The current code would furthermore not work if the disabled parts get
reactivated since vpc_read and vpc_write only use get_sector_offset to
check the allocation status of the first sector of a read/write operation.
This might lead to sectors incorrectly treated as zero in vpc_read and
to sectors getting allocated twice in vpc_write.

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-6-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven
03671ded30 block/vpc: rename footer->size -> footer->current_size
the field is named current size in the spec. Name it accordingly.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1425379316-19639-5-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven
690cbb095a block/vpc: make calculate_geometry spec conform
The VHD spec [1] allows for total_sectors of 65535 x 16 x 255 (~127GB)
represented by a CHS geometry. If total_sectors is greater
than 65535 x 16 x 255 this geometry is set as a maximum.

Qemu, Hyper-V and disk2vhd use this special geometry as an indicator
to use the image current size from the footer as disk size.

This patch changes vpc_create to effectively calculate a CxHxS geometry
for the given image size if possible while rounding up if necessary.
If the image size is too big to be represented in CHS we set the maximum
and write the exact requested image size into the footer.

This partly reverts commit 258d2edb, but leaves support for >127G disks
intact.

[1] http://download.microsoft.com/download/f/f/e/ffef50a5-07dd-4cf8-aaa3-442c0673a029/Virtual%20Hard%20Disk%20Format%20Spec_10_18_06.doc

Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-4-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Kevin Wolf
0444dceee4 vpc: Ignore geometry for large images
The CHS calculation as done per the VHD spec imposes a maximum image
size of ~127 GB. Real VHD images exist that are larger than that.

Apparently there are two separate non-standard ways to achieve this:
You could use more heads than the spec does - this is the option that
qemu-img create chooses.

However, other images exist where the geometry is set to the maximum
(65535/16/255), but the actual image size is larger. Until now, such
images are truncated at 127 GB when opening them with qemu.

This patch changes the vpc driver to ignore geometry in this case and
only trust the size field in the header.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
[PL: Fixed maximum geometry in the commit msg]
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1425379316-19639-3-git-send-email-pl@kamp.de
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Peter Lieven
2ec711dcd4 block/vpc: optimize vpc_co_get_block_status
*pnum can't be greater than s->block_size / BDRV_SECTOR_SIZE for allocated
sectors since there is always a bitmap in between.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1425379316-19639-2-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-03-16 12:10:30 -04:00
Kevin Wolf
0cc8488706 vpc: Implement bdrv_co_get_block_status()
This implements bdrv_co_get_block_status() for VHD images. This can
significantly speed up qemu-img convert operation because only with this
function implemented sparseness can be considered. (Before, converting a
1 TB empty image took several minutes for me, now it's instantaneous.)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-03-09 11:11:59 +01:00
Kevin Wolf
3f3f20dcd3 vpc: Fix size in fixed image creation
If total_sectors is rounded to match the geometry, total_size needs to
be changed as well. Otherwise we end up with an image whose geometry
describes a disk larger than the image file, which doesn't end well.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-03-09 11:11:59 +01:00
Jeff Cody
625fa9fe6f block: remove BLOCK_OPT_NOCOW from vpc_create_opts
In commit fef6070, the need for NOCOW was removed from the vpc driver,
as we removed the the posix calls.  However, the BLOCK_OPT_NOCOW was not
removed from vpc_create_opts.  This was a mistake - remove the opt from
there as well.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 8ba076fa725fed681cde7d8afc4fb239ae06a9c6.1417620301.git.jcody@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Markus Armbruster
bfb197e0d9 block: Eliminate BlockDriverState member device_name[]
device_name[] can become non-empty only in bdrv_new_root() and
bdrv_move_feature_fields().  The latter is used only to undo damage
done by bdrv_swap().  The former is called only by blk_new_with_bs().
Therefore, when a BlockDriverState's device_name[] is non-empty, then
it's been created with a BlockBackend, and vice versa.  Furthermore,
blk_new_with_bs() keeps the two names equal.

Therefore, device_name[] is redundant.  Eliminate it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:26 +02:00
Stefan Hajnoczi
a4127c428e vpc: fix beX_to_cpu() and cpu_to_beX() confusion
The beX_to_cpu() and cpu_to_beX() functions perform the same operation -
they do a byteswap if the host CPU endianness is little-endian or a
nothing otherwise.

The point of two names for the same operation is that it documents which
direction the data is being converted.  This makes it clear whether the
data is suitable for CPU processing or in its external representation.

This patch fixes incorrect beX_to_cpu()/cpu_to_beX() usage.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-25 15:24:14 +02:00
Hu Tao
c2eb918e32 block: round up file size to nearest sector
Currently the file size requested by user is rounded down to nearest
sector, causing the actual file size could be a bit less than the size
user requested. Since some formats (like qcow2) record virtual disk
size in bytes, this can make the last few bytes cannot be accessed.

This patch fixes it by rounding up file size to nearest sector so that
the actual file size is no less than the requested file size.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Xiaodong Gong
0d4cc3e715 Fix improper usage of cpu_to_be32 in vpc
cpu_to_be32() is wrong since vhd_type is an enum constant
(just a regular CPU-endian integer).

Signed-off-by: Xiaodong Gong <gordongong0350@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-10 10:41:29 +02:00
Kevin Wolf
5fb09cd586 vpc: Handle failure for potentially large allocations
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.

This patch addresses the allocations in the vpc block driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-08-15 15:07:16 +02:00
Jeff Cody
fef6070eff block: vpc - use block layer ops in vpc_create, instead of posix calls
Use the block layer to create, and write to, the image file in the VPC
.bdrv_create() operation.

This has a couple of benefits: Images can now be created over protocols,
and hacks such as NOCOW are not needed in the image format driver, and
the underlying file protocol appropriate for the host OS can be relied
upon.

Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-15 15:07:15 +02:00
Chunyan Liu
4ab1559085 qemu-img create: add 'nocow' option
Add 'nocow' option so that users could have a chance to set NOCOW flag to
newly created files. It's useful on btrfs file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this bad
performance is to turn off COW attributes on VM files. Generally, there are
two ways to turn off NOCOW on btrfs: a) by mounting fs with nodatacow, then
all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to the option, it could add NOCOW
per file.

For most block drivers, since the create file step is in raw-posix.c, so we
can do setting NOCOW flag ioctl in raw-posix.c only.

But there are some exceptions, like block/vpc.c and block/vdi.c, they are
creating file by calling qemu_open directly. For them, do the same setting
NOCOW flag ioctl work in them separately.

[Fixed up 082.out due to the new 'nocow' creation option
--Stefan]

Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-01 10:15:12 +02:00
Chunyan Liu
c282e1fdf7 cleanup QEMUOptionParameter
Now that all backend drivers are using QemuOpts, remove all
QEMUOptionParameter related codes.

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Chunyan Liu
fec9921f0a vpc.c: replace QEMUOptionParameter with QemuOpts
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Kevin Wolf
5e71dfad76 vpc: Validate block size (CVE-2014-0142)
This fixes some cases of division by zero crashes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 13:59:47 +02:00
Jeff Cody
97f1c45c6f vpc/vhd: add bounds check for max_table_entries and block_size (CVE-2014-0144)
This adds checks to make sure that max_table_entries and block_size
are in sane ranges.  Memory is allocated based on max_table_entries,
and block_size is used to calculate indices into that allocated
memory, so if these values are incorrect that can lead to potential
unbounded memory allocation, or invalid memory accesses.

Also, the allocation of the pagetable is changed from g_malloc0()
to qemu_blockalign().

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 13:59:47 +02:00
Paolo Bonzini
76abe4071d block: do not abuse EMEDIUMTYPE
Returning "Wrong medium type" for an image that does not have a valid
header is a bit weird.  Improve the error by mentioning what format
was trying to open it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:24 +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
Paolo Bonzini
97b00e2851 vpc, vhdx: add get_info
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
Peter Lieven
0173e7bbf3 block/vpc: fix virtual size for images created with disk2vhd
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07 13:58:58 +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
Jeff Cody
e54835c06d block: vpc - use QEMU_PACKED for on-disk structures
The VHD footer and header structs (vhd_footer and vhd_dyndisk_header)
are on-disk structures for the image format, and as such should be
packed.

Go ahead and make these typedefs as well, with the preferred QEMU
naming convention, so that the packed attribute is used consistently
with the struct.

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 20:51:10 +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
Kevin Wolf
72c6cc94da vpc: Implement .bdrv_has_zero_init
Depending on the subformat, has_zero_init on VHD must behave like raw
and query the underlying storage (fixed) or like other sparse formats
that can always return 1 (dynamic, differencing).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 10:21:00 +02:00
Kevin Wolf
1a86938f04 block: Add options QDict to .bdrv_open()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-15 16:07:49 +01:00
Stefan Hajnoczi
33ccf6675f Revert "block/vpc: Fix size calculation"
This reverts commit f880defbb0.

Jeff Cody's testing revealed that the interpretation of size differs
even between VirtualPC and HyperV.  Revert this so there is time to
consider the impact of any backwards incompatible behavior this change
creates.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-02-12 12:25:15 +01:00
Stefan Weil
f880defbb0 block/vpc: Fix size calculation
The size calculated from the CHS values is not the real image (disk) size,
but usually a smaller value. This is caused by rounding effects.

Only older operating systems use CHS. Such guests won't be able to use
the whole disk. All modern operating systems use the real size.

This patch fixes https://bugs.launchpad.net/qemu/+bug/1105670/.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-id: 1360265212-22037-1-git-send-email-sw@weilnetz.de
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-02-11 08:14:41 -06:00
Kevin Wolf
59294e4659 vpc: Fix bdrv_open() error handling
Return -errno instead of -1 on errors. While touching the
code, fix a memory leak.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-02-01 14:58:28 +01:00
Paolo Bonzini
1de7afc984 misc: move include files to include/qemu/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:32:39 +01:00
Paolo Bonzini
caf71f86a3 migration: move include files to include/migration/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:32 +01:00
Paolo Bonzini
737e150e89 block: move include files to include/block/
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-12-19 08:31:31 +01:00
Charles Arnold
258d2edbcd block: vpc support for ~2 TB disks
The VHD specification allows for up to a 2 TB disk size. The current
implementation in qemu emulates EIDE and ATA-2 hardware which only allows
for up to 127 GB.  This disk size limitation can be overridden by allowing
up to 255 heads instead of the normal 4 bit limitation of 16.  Doing so
allows disk images to be created of up to nearly 2 TB.  This change does
not violate the VHD format specification nor does it change how smaller
disks (ie, <=127GB) are defined.

[Charles Arnold also writes: "In analyzing a 160 GB VHD fixed disk image
created on Windows 2008 R2, it appears that MS is also ignoring the CHS
values in the footer geometry field in whatever driver they use for
accessing the image.  The CHS values are set at 65535,16,255 which
obviously doesn't represent an image size of 160 GB." -- Stefan]

Signed-off-by: Charles Arnold <carnold@suse.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-12-11 11:04:26 +01:00
Charles Arnold
1fe1fa510a block: vpc initialize the uuid footer field
Initialize the uuid field in the footer with a generated uuid.

Signed-off-by: Charles Arnold <carnold@suse.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2012-12-11 11:04:25 +01:00
Jeff Cody
3fe4b70008 block: vpc image file reopen
There is currently nothing that needs to be done for VPC image
file reopen.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-09-24 15:15:12 +02:00
Corey Bryant
2e1e79dae7 block: Convert close calls to qemu_close
This patch converts all block layer close calls, that correspond
to qemu_open calls, to qemu_close.

Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-15 10:48:57 +02:00
Corey Bryant
6165f4d85d block: Convert open calls to qemu_open
This patch converts all block layer open calls to qemu_open.

Note that this adds the O_CLOEXEC flag to the changed open paths
when the O_CLOEXEC macro is defined.

Signed-off-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-08-15 10:48:57 +02:00
Zhang Shengju
c088b69136 block/vpc: write checksum back to footer after check
After validation check, the 'checksum' is not written back
to footer, which leave it with zero.

This results in errors while loadding it under Microsoft's
Hyper-V environment, and also errors from utilities like
Citrix's vhd-util.

Signed-off-by: Zhang Shengju <sean_zhang@trendmicro.com.cn>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-04-05 14:54:40 +02:00
Paolo Bonzini
29cdb2513c block: push recursive flushing up from drivers
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-04-05 14:54:39 +02:00
Kevin Wolf
ecd880d9ee vpc: Round up image size during fixed image creation
The geometry calculation algorithm from the VHD spec rounds the image
size down if it doesn't exactly match a geometry. During image
conversion, this causes the image to be truncated. For dynamic images,
we already have code in place to round up instead, let's do the same for
fixed images.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-02-09 16:17:51 +01:00
Charles Arnold
24da78dbb5 vpc: Add support for Fixed Disk type
The Virtual Hard Disk Image Format Specification allows for three
types of hard disk formats, Fixed, Dynamic, and Differencing.  Qemu
currently only supports Dynamic disks.  This patch adds support for
the Fixed Disk format.

Usage:
    Example 1: qemu-img create -f vpc -o type=fixed <filename> [size]
    Example 2: qemu-img convert -O vpc -o type=fixed <input filename> <output filename>

While it is also allowed to specify '-o type=dynamic', the default disk type
remains Dynamic and is what is used when the type is left unspecified.

Signed-off-by: Charles Arnold <carnold@suse.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-02-09 16:17:51 +01:00
Kevin Wolf
5bb1cbac4f vpc: Add missing error handling in alloc_block
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-11-23 17:04:06 +01:00
Kevin Wolf
612ff3d887 vpc: Add migration blocker
vpc caches the BAT. For migration to work, it would have to be
invalidated. Block migration for now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-23 17:04:04 +01:00
Kevin Wolf
c68b89acd6 block: Rename bdrv_co_flush to bdrv_co_flush_to_disk
There are two different types of flush that you can do: Flushing one level up
to the OS (i.e. writing data to the host page cache) or flushing it all the way
down to the disk. The existing functions flush to the disk, reflect this in the
function name.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:59 +01:00
Charles Arnold
78439f6af1 block: Fix vpc initialization of the Dynamic Disk Header
The Data Offset field in the Dynamic Disk Header is an 8 byte field.
Although the specification (2006-10-11) gives an example of initializing
only the first 4 bytes, images generated by Microsoft on Windows initialize
all 8 bytes.

Failure to initialize all 8 bytes results in errors from utilities
like Citrix's vhd-util which checks specifically for the proper Data
Offset field initialization.

Signed-off-by: Charles Arnold <carnold@suse.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-11-11 14:02:58 +01:00
Paolo Bonzini
8b94ff8573 block: change flush to co_flush
Since coroutine operation is now mandatory, convert all bdrv_flush
implementations to coroutines.  For qcow2, this means taking the lock.
Other implementations are simpler and just forward bdrv_flush to the
underlying protocol, so they can avoid the lock.

The bdrv_flush callback is then unused and can be eliminated.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-10-21 17:34:14 +02:00