Commit graph

345 commits

Author SHA1 Message Date
Nicholas Thomas f785a5ae36 block/curl: Handle failed reads gracefully.
Current behaviour if a read fails is for the acb to not get finished.
This causes an infinite loop in bdrv_read_em (block.c). The read failure
never gets reported to the  guest and if the error condition clears, the
process never recovers.

With this patch, when curl reports a failure we finish the acb as a
failure. This results in the guest receiving an I/O error (rather than
the read hanging indefinitely) and if the error condition subsequently
clears, retries work as expected.

The simplest test is to put an ISO on a web server you have control over
and open it with qemu-io. Then move the ISO out of the way and attempt
to read some data - you should see behaviour matching the above.

Signed-off-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23 17:41:14 +02:00
Scott Wood de33b1f3dd qcow: initialize coroutine mutex
commit 52b8eb6013 added a mutex,
but never initialized it.  This caused a segfault.

Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23 14:15:17 +02:00
Devin Nakamura d57237f291 qcow2: fix typo in documentation for qcow2_get_cluster_offset()
Documentation states the num is measured in clusters, but its
actually measured in sectors

Signed-off-by: Devin Nakamura <devin122@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23 14:15:17 +02:00
Philipp Hahn 6cbc3031c8 qcow2: Fix DEBUG_* compilation
By introducing BlockDriverState compiling qcow2 with DEBUG_ALLOC and DEBUG_EXT
defined got broken.
Define a BdrvCheckResult structure locally which is now needed as the second
argument.

Also fix qcow2_read_extensions() needing BDRVQcowState.

Signed-off-by: Philipp Hahn <hahn@univention.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-23 14:15:17 +02:00
Stefan Weil 2c993ec294 w32: Fix qemu_ftruncate64
SetFilePointer returns INVALID_SET_FILE_POINTER when it fails.
In addition, GetLastError must be checked.

The first call of SetFilePointer did not use INVALID_SET_FILE_POINTER,
the second call used wrong error handling.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-22 10:19:00 -05:00
Anthony Liguori 7267c0947d Use glib memory allocation and free functions
qemu_malloc/qemu_free no longer exist after this commit.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-20 23:01:08 -05:00
Kevin Wolf 35d7ace74b qcow2: Fix L1 table size after bdrv_snapshot_goto
When loading an internal snapshot whose L1 table is smaller than the current L1
table, the size of the current L1 would be shrunk to the snapshot's L1 size in
memory, but not on disk. This lead to incorrect refcount updates and eventuelly
to image corruption.

Instead of writing the new L1 size to disk, this simply retains the bigger L1
size that is currently in use and makes sure that the unused part is zeroed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Philipp Hahn <hahn@univention.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-08-05 07:15:47 -05:00
Kevin Wolf 384acbf46b async: Remove AsyncContext
The purpose of AsyncContexts was to protect qcow and qcow2 against reentrancy
during an emulated bdrv_read/write (which includes a qemu_aio_wait() call and
can run AIO callbacks of different requests if it weren't for AsyncContexts).

Now both qcow and qcow2 are protected by CoMutexes and AsyncContexts can be
removed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02 15:53:41 +02:00
Kevin Wolf 52b8eb6013 qcow: Use coroutines
The old qcow format is another user of the AsyncContext infrastructure.
Converting it to coroutines (and therefore CoMutexes) allows to remove
AsyncContexts.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02 15:53:41 +02:00
Kevin Wolf 68d100e905 qcow2: Use coroutines
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-02 15:53:41 +02:00
Frediano Ziglio f6e8ffc22f raw-posix: Always check paio_init result
Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:29 +02:00
Frediano Ziglio c1ee7d56f3 raw-posix: Typo fix
Signed-off-by: Frediano Ziglio <freddy77@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:29 +02:00
Serge E. Hallyn efc8243d00 block/vpc.c: Detect too-large vpc file
VHD files technically can be up to 2Tb, but virtual pc is limited
to 127G.  Currently qemu-img refused to create vpc files > 127G,
but it is failing to return error when converting from a non-vpc
VHD file which is >127G.  It returns success, but creates a truncated
converted image.  Also, qemu-img info claims the vpc file is 127G
(and clean).

This patch detects a too-large vpc file and returns -EFBIG.  Without
this patch,

=============================================================
root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/140g-dynamic.vhd
image: /mnt/140g-dynamic.vhd
file format: vpc
virtual size: 127G (136899993600 bytes)
disk size: 284K
root@ip-10-38-123-242:~/qemu-fixed# qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y
root@ip-10-38-123-242:~/qemu-fixed# echo $?
0
root@ip-10-38-123-242:~/qemu-fixed# qemu-img info /mnt/y
image: /mnt/y
file format: raw
virtual size: 127G (136899993600 bytes)
disk size: 0
=============================================================

(The 140G image was truncated with no warning or error.)

With the patch, I get:

=============================================================
root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img info /mnt/140g-dynamic.vhd
qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large
root@ip-10-38-123-242:~/qemu-fixed# ./qemu-img convert -f vpc -O raw /mnt/140g-dynamic.vhd /mnt/y
qemu-img: Could not open '/mnt/140g-dynamic.vhd': File too large
qemu-img: Could not open '/mnt/140g-dynamic.vhd'
=============================================================

See https://bugs.launchpad.net/qemu/+bug/814222 for details.

Signed-off-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:28 +02:00
Markus Armbruster 822e1cd17e block: Make BlockDriver method bdrv_eject() return void
Callees always return 0, except for FreeBSD's cdrom_eject(), which
returns -ENOTSUP when the device is in a terminally wedged state.

The only caller is bdrv_eject(), and it maps -ENOTSUP to 0 since
commit 4be9762a.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:28 +02:00
Markus Armbruster 7bf37feddc block: Make BlockDriver method bdrv_set_locked() return void
The only caller is bdrv_set_locked(), and it ignores the value.

Callees always return 0, except for FreeBSD's cdrom_set_locked(),
which returns -ENOTSUP when the device is in a terminally wedged
state.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:28 +02:00
Markus Armbruster 02266d547a block/raw-win32: Drop disabled code for removable host devices
It's been disabled since the start (commit 19cb3738, Aug 2006), and
has been untouched except for spelling fixes and such.  I don't feel
like dragging it along any further.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-08-01 12:10:28 +02:00
Blue Swirl 00aa0040e8 Wrap recv to avoid warnings
Avoid warnings like these by wrapping recv():
  CC    slirp/ip_icmp.o
/src/qemu/slirp/ip_icmp.c: In function 'icmp_receive':
/src/qemu/slirp/ip_icmp.c:418:5: error: passing argument 2 of 'recv' from incompatible pointer type [-Werror]
/usr/local/lib/gcc/i686-mingw32msvc/4.6.0/../../../../i686-mingw32msvc/include/winsock2.h:547:32: note: expected 'char *' but argument is of type 'struct icmp *'

Remove also casts used to avoid warnings.

Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-07-25 14:38:56 +00:00
Kevin Wolf 93913dfd8a qcow2: Use Qcow2Cache in writeback mode during loadvm/savevm
In snapshotting there is no guest involved, so we can safely use a writeback
mode and do the flushes in the right place (i.e. at the very end). This
improves the time that creating/restoring an internal snapshot takes with an
image in writethrough mode.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:22 +02:00
Fam Zheng 4a1d5e1fde block: add bdrv_get_allocated_file_size() operation
qemu-img.c wants to count allocated file size of image. Previously it
counts a single bs->file by 'stat' or Window API. As VMDK introduces
multiple file support, the operation becomes format specific with
platform specific meanwhile.

The functions are moved to block/raw-{posix,win32}.c and qemu-img.c calls
bdrv_get_allocated_file_size to count the bs. And also added VMDK code
to count his own extents.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:08 +02:00
Fam Zheng ae261c86aa VMDK: fix coding style
Conform coding style in vmdk.c to pass scripts/checkpatch.pl checks.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:07 +02:00
Fam Zheng f66fd6c383 VMDK: create different subformats
Add create option 'format', with enums:
    monolithicSparse
    monolithicFlat
    twoGbMaxExtentSparse
    twoGbMaxExtentFlat
Each creates a subformat image file. The default is monolithicSparse.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:07 +02:00
Fam Zheng 7fa60fa377 VMDK: open/read/write for monolithicFlat image
Parse vmdk decriptor file and open mono flat image.
Read/write the flat extent.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:07 +02:00
Fam Zheng 91b85bd388 VMDK: change get_cluster_offset return type
The return type of get_cluster_offset was an offset that use 0 to denote
'not allocated', this will be no longer true for flat extents, as we see
flat extent file as a single huge cluster whose offset is 0 and length
is the whole file length.
So now we use int return value, 0 means success and otherwise offset
invalid.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:07 +02:00
Fam Zheng 69b4d86d9f VMDK: move 'static' cid_update flag to bs field
Cid_update is the flag for updating CID on first write after opening the
image. This should be per image open rather than per program life cycle,
so change it from static var of vmdk_write to a field in BDRVVmdkState.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:07 +02:00
Fam Zheng 333c574d05 VMDK: flush multiple extents
Flush all the file that referenced by the image.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:06 +02:00
Fam Zheng e1da9b2433 VMDK: add field BDRVVmdkState.desc_offset
There are several occurrence of magic number 0x200 as the descriptor
offset within mono sparse image file. This is not the case for images
with separate descriptor file. So a field is added to BDRVVmdkState to
hold the correct value.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:06 +02:00
Fam Zheng b4b3ab146c VMDK: separate vmdk_open by format version
Separate vmdk_open by subformats to:
* vmdk_open_vmdk3
* vmdk_open_vmdk4

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:06 +02:00
Fam Zheng 01fc99d6a8 VMDK: probe for monolithicFlat images
Probe as the same behavior as VMware does.
Recognize image as monolithicFlat descriptor file when the file is text
and the first effective line (not '#' leaded comment or space line) is
either 'version=1' or 'version=2'. No space or upper case charactors
accepted.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:06 +02:00
Fam Zheng 0e69c54394 VMDK: bugfix, align offset to cluster in get_whole_cluster
In get_whole_cluster, the offset is not aligned to cluster when reading
from backing_hd. When the first write to child is not at the cluster
boundary, wrong address data from parent is copied to child.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:06 +02:00
Fam Zheng b3976d3c8b VMDK: introduce VmdkExtent
Introduced VmdkExtent array into BDRVVmdkState, enable holding multiple
image extents for multiple file image support.

Signed-off-by: Fam Zheng <famcool@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-19 15:39:05 +02:00
MORITA Kazutaka a8e0fdd715 sheepdog: add full data preallocation support
This introduces qemu-img create option for sheepdog which allows the
data to be fully preallocated (note that sheepdog always preallocates
metadata).

The option is disabled by default and you need to enable it like the
following:

qemu-img create sheepdog:test -o preallocation=full 1G

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-18 16:06:26 +02:00
Johannes Stezenbach 343f85685c block/raw-posix: Linux compat-ioctl warning workaround
On Linux x86_64 host with 32bit userspace, running
qemu or even just "qemu-img create -f qcow2 some.img 1G"
causes a kernel warning:

ioctl32(qemu-img:5296): Unknown cmd fd(3) cmd(00005326){t:'S';sz:0} arg(7fffffff) on some.img
ioctl32(qemu-img:5296): Unknown cmd fd(3) cmd(801c0204){t:02;sz:28} arg(fff77350) on some.img

ioctl 00005326 is CDROM_DRIVE_STATUS,
ioctl 801c0204 is FDGETPRM.

The warning appears because the Linux compat-ioctl handler for these
ioctls only applies to block devices, while qemu also uses the ioctls on
plain files.  Work around by calling fstat() the ensure the ioctls are
only used on block devices.

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-07-05 11:23:29 +02:00
Markus Armbruster 6daf194dde Strip trailing '\n' from error_report()'s first argument
error_report() prepends location, and appends a newline.  The message
constructed from the arguments should not contain a newline.  Fix the
obvious offenders.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-06-24 09:13:36 +01:00
Markus Armbruster db78ef5b0a sheepdog: qemu_bh_new() can't return null pointer, drop check
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-06-24 09:13:36 +01:00
Kevin Wolf 9e2a3701a1 qcow2: Fix in-flight list after qcow2_cache_put failure
If qcow2_cache_put returns an error during cluster allocation and the
allocation fails, it must be removed from the list of in-flight allocations.
Otherwise we'd get a loop in the list when the ACB is used for the next
allocation.

Luckily, this qcow2_cache_put shouldn't fail anyway because the L2 table is
only read, so that qcow2_cache_put doesn't even involve I/O.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2011-06-15 14:36:15 +02:00
Kevin Wolf e67a64a869 vdi: Avoid direct AIO callback
bdrv_aio_* must not call the callback before returning to its caller. In vdi,
this could happen in some error cases. This starts the real requests processing
in a BH to avoid this situation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-15 14:35:15 +02:00
Kevin Wolf b11a24dee6 qcow: Avoid direct AIO callback
bdrv_aio_* must not call the callback before returning to its caller. In qcow,
this could happen in some error cases. This starts the real requests processing
in a BH to avoid this situation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-14 17:03:27 +02:00
Kevin Wolf 42496d6240 qcow2: Avoid direct AIO callback
bdrv_aio_* must not call the callback before returning to its caller. In qcow2,
this could happen in some error cases. This starts the real requests processing
in a BH to avoid this situation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-14 17:03:25 +02:00
Stefan Weil 7bf4162a80 block/rbd: Remove unused local variable
Variable 'snap' is assigned a value that is never used.
Remove snap and the related code.

Cc: Christian Brunner <chb@muc.de>
Cc: Josh Durgin <josh.durgin@dreamhost.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Reviewed-by: Josh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-14 10:01:19 +02:00
Anthony Liguori 13748cf499 Merge remote-tracking branch 'stefanha/trivial-patches' into staging 2011-06-08 12:13:58 -05:00
Kevin Wolf 99cce9fa4e qemu-img create: Fix displayed default cluster size
When not specifying a cluster size on the command line, qemu-img printed
a cluster size of 0:

    Formatting '/tmp/test.qcow2', fmt=qcow2 size=67108864
    encryption=off cluster_size=0

This patch adds the default cluster size to the QEMUOptionParameter list, so
that it displays the default value that is used.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:40 +02:00
Kevin Wolf 80fa3341a7 qcow2: Fix memory leaks in error cases
This fixes memory leaks that may be caused by I/O errors during L1 table growth
(can happen during save_vm) and in qemu-img check.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:40 +02:00
Josh Durgin 30cdc48cc8 rbd: Add bdrv_truncate implementation
Reviewed-by: Christian Brunner <chb@muc.de>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:40 +02:00
Josh Durgin 51a135287a rbd: check return values when scheduling aio
If scheduling fails, the number of outstanding I/Os must be correct,
or there will be a hang when waiting for everything to be flushed.

Reviewed-by: Christian Brunner <chb@muc.de>
Reported-by: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:40 +02:00
Josh Durgin fab5cf592c rbd: allow configuration of rados from the rbd filename
The new format is rbd:pool/image[@snapshot][:option1=value1[:option2=value2...]]
Each option is used to configure rados, and may be any Ceph option, or "conf".
The "conf" option specifies a Ceph configuration file to read.

This allows rbd volumes from more than one Ceph cluster to be used by
specifying different monitor addresses, as well as having different
logging levels or locations for different volumes.

Reviewed-by: Christian Brunner <chb@muc.de>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:40 +02:00
Josh Durgin ad32e9c003 rbd: use the higher level librbd instead of just librados
librbd stacks on top of librados to provide access
to rbd images.

Using librbd simplifies the qemu code, and allows
qemu to use new versions of the rbd format
with few (if any) changes.

Reviewed-by: Christian Brunner <chb@muc.de>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.com>
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:39 +02:00
Christoph Egger d1f6fd8d14 block/raw-posix: get right partition size
use the correct way to get the size of a disk device or partition

From: Adam Hamsik <haad@netbsd.org>
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 11:56:39 +02:00
Christoph Egger 1de1ae0a7d block/raw-posix: use a character device if a block device is given
On NetBSD a userland process is better with the character device
interface. In addition, a block device can't be opened twice; if a Xen
backend opens it, qemu can't and vice-versa.

Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 10:39:32 +02:00
Alexander Graf 16372ff03d vmdk: fix endianness bugs
The vmdk code is sloppy when handling the header descriptor during
creation of an image. Fix all header accesses in the create path to
either store native endianness or convert it when appropriate.

Reported-by: Yury Tsarev <ytsarev@novell.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 10:39:32 +02:00
Christoph Hellwig a659979328 block: clarify the meaning of BDRV_O_NOCACHE
Change BDRV_O_NOCACHE to only imply bypassing the host OS file cache,
but no writeback semantics.  All existing callers are changed to also
specify BDRV_O_CACHE_WB to give them writeback semantics.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-06-08 10:39:32 +02:00