Commit Graph

272 Commits

Author SHA1 Message Date
Kevin Wolf
1b40bbd13a raw-win32: Fix bdrv_flush return value
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-31 10:03:00 +01:00
Stefan Hajnoczi
0d09c79700 qed: Images with backing file do not require QED_F_NEED_CHECK
The consistency check on open is necessary in order to fix inconsistent
table offsets left as a result of a crash mid-operation.  Images with a
backing file actually flush before updating table offsets and are
therefore guaranteed to be consistent.  Do not mark these images dirty.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-31 10:03:00 +01:00
Kevin Wolf
5ea929e3d1 qcow2: Add bdrv_discard support
This adds a bdrv_discard function to qcow2 that frees the discarded clusters.
It does not yet pass the discard on to the underlying file system driver, but
the space can be reused by future writes to the image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-01-31 10:03:00 +01:00
MORITA Kazutaka
b444736346 sheepdog: support creating images on remote hosts
This patch parses the input filename in sd_create(), and enables us
specifying a target server to create sheepdog images.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-31 10:03:00 +01:00
Jes Sorensen
bf595021c7 Reorganize struct Qcow2Cache for better struct packing
Move size after the two pointers in struct Qcow2Cache to get better
packing of struct elements on 64 bit architectures.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-31 10:03:00 +01:00
Stefan Hajnoczi
c743849bee qed: Refuse to create images on block devices
QED relies on the underlying filesystem to extend the file and maintain
its size.  Check that images are not created on a block device.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24 16:41:50 +01:00
Kevin Wolf
3de0a2944b qcow2: Batch flushes for COW
qcow2 calls bdrv_flush() after performing COW in order to ensure that the
L2 table change is never written before the copy is safe on disk. Now that the
L2 table is cached, we can wait with flushing until we write out the next L2
table.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24 16:41:49 +01:00
Kevin Wolf
29c1a7301a qcow2: Use QcowCache
Use the new functions of qcow2-cache.c for everything that works on refcount
block and L2 tables.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24 16:41:49 +01:00
Kevin Wolf
493810940b qcow2: Add QcowCache
This adds some new cache functions to qcow2 which can be used for caching
refcount blocks and L2 tables. When used with cache=writethrough they work
like the old caching code which is spread all over qcow2, so for this case we
have merely a cleanup.

The interesting case is with writeback caching (this includes cache=none) where
data isn't written to disk immediately but only kept in cache initially. This
leads to some form of metadata write batching which avoids the current "write
to refcount block, flush, write to L2 table" pattern for each single request
when a lot of cluster allocations happen. Instead, cache entries are only
written out if its required to maintain the right order. In the pure cluster
allocation case this means that all metadata updates for requests are done in
memory initially and on sync, first the refcount blocks are written to disk,
then fsync, then L2 tables.

This improves performance of scenarios with lots of cluster allocations
noticably (e.g. installation or after taking a snapshot).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24 11:08:51 +01:00
Aurelien Jarno
653df36bbe qcow2: fix unaligned access
cpu_to_be64w() is called with an obviously non-aligned pointer. Use
cpu_to_be64wu() instead. It fixes unaligned accesses errors on IA64
hosts.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-24 11:08:50 +01:00
Blue Swirl
f0ff243a16 vpc: fix a file descriptor leak
Fix a file descriptor leak, reported by cppcheck:
[/src/qemu/block/vpc.c:524]: (error) Resource leak: fd

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-01-12 19:49:00 +00:00
Blue Swirl
08089edcd2 vvfat: fix a file descriptor leak
Fix a file descriptor leak, reported by cppcheck:
[/src/qemu/block/vvfat.c:759]: (error) Resource leak: dir

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2011-01-12 19:48:58 +00:00
Jes Sorensen
6d85a57e20 Add proper -errno error return values to qcow2_open()
In addition this adds missing braces to the function to be consistent
with the coding style.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:15:04 +01:00
Jes Sorensen
7c80ab3f21 block/qcow2.c: rename qcow_ functions to qcow2_
It doesn't really make sense for functions in qcow2.c to be named
qcow_ so convert the names to match correctly.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:15:01 +01:00
Stefan Hajnoczi
01979a98d7 qed: Consistency check support
This patch adds support for the qemu-img check command.  It also
introduces a dirty bit in the qed header to mark modified images as
needing a check.  This bit is cleared when the image file is closed
cleanly.

If an image file is opened and it has the dirty bit set, a consistency
check will run and try to fix corrupted table offsets.  These
corruptions may occur if there is power loss while an allocating write
is performed.  Once the image is fixed it opens as normal again.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:04 +01:00
Stefan Hajnoczi
eabba580e6 qed: Read/write support
This patch implements the read/write state machine.  Operations are
fully asynchronous and multiple operations may be active at any time.

Allocating writes lock tables to ensure metadata updates do not
interfere with each other.  If two allocating writes need to update the
same L2 table they will run sequentially.  If two allocating writes need
to update different L2 tables they will run in parallel.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:04 +01:00
Stefan Hajnoczi
298800cae7 qed: Table, L2 cache, and cluster functions
This patch adds code to look up data cluster offsets in the image via
the L1/L2 tables.  The L2 tables are writethrough cached in memory for
performance (each read/write requires a lookup so it is essential to
cache the tables).

With cluster lookup code in place it is possible to implement
bdrv_is_allocated() to query the number of contiguous
allocated/unallocated clusters.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:04 +01:00
Stefan Hajnoczi
75411d236d qed: Add QEMU Enhanced Disk image format
This patch introduces the qed on-disk layout and implements image
creation.  Later patches add read/write and other functionality.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:04 +01:00
Christoph Hellwig
dce512dedf raw-posix: add discard support
Add support to discard blocks in a raw image residing on an XFS filesystem
by calling the XFS_IOC_UNRESVSP64 ioctl to punch holes.  Support for other
hole punching mechanisms can be added when they become available.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:03 +01:00
Christoph Hellwig
bb8bf76fb1 block: add discard support
Add a new bdrv_discard method to free blocks in a mapping image, and a new
drive property to set the granularity for these discard.  If no discard
granularity support is set discard support is disabled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-17 16:11:03 +01:00
Christian Brunner
f27aaf4b53 ceph/rbd block driver for qemu-kvm
RBD is an block driver for the distributed file system Ceph
(http://ceph.newdream.net/). This driver uses librados (which is part
of the Ceph server) for direct access to the Ceph object store and is
running entirely in userspace (Yehuda also wrote a driver for the
linux kernel, that can be used to access rbd volumes as a block
device).

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Christian Brunner <chb@muc.de>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-12-14 15:44:21 +01:00
Christoph Hellwig
11a3cb8159 raw-posix: raw_pwrite comment fixup
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-26 19:02:52 +01:00
Kevin Wolf
80465c5016 block: Remove unused s->hd in various drivers
All drivers use bs->file instead of s->hd for quite a while now, so it's time
to remove s->hd.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2010-11-24 17:31:06 +01:00
Blue Swirl
cfd07e7abb Fix win32 build
Fix a return value change missed by
205ef7961f.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-11-07 15:10:40 +00:00
Blue Swirl
a313358636 block: avoid a warning on 64 bit hosts with long as int64_t
When building on a 64 bit host which uses 'long' for int64_t,
GCC emits a warning:
  CC    block/blkverify.o
/src/qemu/block/blkverify.c: In function `blkverify_verify_readv':
/src/qemu/block/blkverify.c:304: warning: long long int format, long
unsigned int arg (arg 3)

Rework a77cffe7e9 to avoid the warning.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-04 13:54:37 +01:00
Kevin Wolf
1c02e2a171 qcow2: Invalidate cache after failed read
The cache content may be destroyed after a failed read, better not use it any
more.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2010-11-04 13:54:37 +01:00
Kevin Wolf
4a4111851f vpc: Implement bdrv_flush
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-11-04 12:52:16 +01:00
Kevin Wolf
205ef7961f block: Allow bdrv_flush to return errors
This changes bdrv_flush to return 0 on success and -errno in case of failure.
It's a requirement for implementing proper error handle in users of bdrv_flush.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2010-11-04 12:52:16 +01:00
Anthony Liguori
21bcc5907f Merge remote branch 'kwolf/for-anthony' into staging 2010-10-26 09:50:58 -05:00
Blue Swirl
c57c846a80 qemu-timer: move commonly used timer code to qemu-timer-common
Move timer init functions to a new file, qemu-timer-common.c. Make other
critical timer functions inlined to preserve performance in
qemu-timer.c, also move muldiv64() (used by the inline functions)
to qemu-timer.h.

Adjust block/raw-posix.c and simpletrace.c to use get_clock() directly.
Remove a similar/duplicate definition in qemu-tool.c.

Adjust hw/omap_clk.c to include qemu-timer.h because muldiv64() is used
there.

After this change, tracing can be used also for user code and
simpletrace on Win32.

Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-23 15:24:07 +00:00
Stefan Weil
a77cffe7e9 block: Use GCC_FMT_ATTR and fix a format error
Adding the gcc format attribute detects a format bug
which is fixed here.

v2:
Don't use type cast. BDRV_SECTOR_SIZE is unsigned long long,
so %lld should be the correct format specifier.

Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00
edison
51ef67270b Copy snapshots out of QCOW2 disk
In order to backup snapshots, created from QCOW2 iamge, we want to copy snapshots out of QCOW2 disk to a seperate storage.
The following patch adds a new option in "qemu-img": qemu-img convert -f qcow2 -O qcow2 -s snapshot_name src_img bck_img.
Right now, it only supports to copy the full snapshot, delta snapshot is on the way.

Changes from V1: all the comments from Kevin are addressed:
Add read-only checking
Fix coding style
Change the name from bdrv_snapshot_load to bdrv_snapshot_load_tmp

Signed-off-by: Disheng Su <edison@cloud.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00
Kevin Wolf
9b036055ef qcow2: Remove old image creation function
They have been #ifdef'd out by the previous patch.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00
Kevin Wolf
a9420734b6 qcow2: Simplify image creation
Instead of doing lots of magic for setting up initial refcount blocks and stuff
create a minimal (inconsistent) image, open it and initialize the rest with
regular qcow2 functions.

This is a complete rewrite of the image creation function. The old
implementating is #ifdef'd out and will be removed by the next patch (removing
it here would have made the diff unreadable because diff tries to find
similarities when it's really a rewrite)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00
Stefan Hajnoczi
72893756e0 qcow2: Support exact L1 table growth
The L1 table grow operation includes a size calculation that bumps up
the new L1 table size in order to anticipate the size needs of vmstate
data.  This helps reduce the number of times that the L1 table has to be
grown when vmstate data is appended.

This size overhead is not necessary during image creation,
bdrv_truncate(), or snapshot goto operations.  In fact, existing
qemu-iotests that exercise table growth are no longer able to trigger it
because image creation preallocates an L1 table that is too large after
changes to qcow_create2().

This patch keeps the size calculation but also adds exact growth for
callers that do not want to inflate the L1 table size unnecessarily.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-10-22 14:49:35 +02:00
Blue Swirl
83e3f76c25 block: avoid a write only variable
Compiling with GCC 4.6.0 20100925 produced a warning:
/src/qemu/block/qcow2-refcount.c: In function 'update_refcount':
/src/qemu/block/qcow2-refcount.c:552:13: error: variable 'dummy' set but not used [-Werror=unused-but-set-variable]

Fix by adding a dummy cast so that the result is not unused.

Acked-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-13 18:38:07 +00:00
Stefan Weil
d523d5d694 block/vvfat: Fix compiler warning in debug code
Fix this compiler warning:
./block/vvfat.c:2285: error: comparison of unsigned expression >= 0 is always true

Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-10-03 06:40:54 +00:00
Anthony Liguori
687db4ed2e block-verify: fix 32-bit build
Reported-by: Peter Lemenkov <lemenkov@gmail.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-09-22 14:46:33 -05:00
Stefan Hajnoczi
d9d334176c blkverify: Add block driver for verifying I/O
The blkverify block driver makes investigating image format data
corruption much easier.  A raw image initialized with the same contents
as the test image (e.g. qcow2 file) must be provided.  The raw image
mirrors read/write operations and is used to verify that data read from
the test image is correct.

See docs/blkverify.txt for more information.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 17:00:53 +02:00
Kevin Wolf
6f5f060b73 qcow2: Avoid bounce buffers for AIO write requests
qcow2 used to use bounce buffers for any AIO requests. This does not only imply
unnecessary copying, but also unbounded allocations which should be avoided.

This patch removes bounce buffers from the normal AIO write path. Encrypted
images continue to use a bounce buffer, however with constant size.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:43 +02:00
Kevin Wolf
bd28f83565 qcow2: Avoid bounce buffers for AIO read requests
qcow2 used to use bounce buffers for any AIO requests. This does not only imply
unnecessary copying, but also unbounded allocations which should be avoided.

This patch removes bounce buffers from the normal AIO read path, and constrains
them to a constant size for encrypted images.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Kevin Wolf
9f8e668eb1 qcow2: Get rid of additional sync on COW
We always have a sync for the refcount update when a new cluster is
allocated. If we move this past the COW, we can save an additional sync.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Kevin Wolf
29216ed14f qcow2: Move sync out of qcow2_alloc_clusters
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Kevin Wolf
1c4c28149f qcow2: Move sync out of update_refcount
Note that the flush is omitted intentionally in qcow2_free_clusters. If
anything, we can leak clusters here if we lose the writes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Kevin Wolf
c01828fb51 qcow2: Move sync out of write_refcount_block_entries
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Laurent Vivier
c2e2872bf4 nbd: correctly manage default port
block/nbd.c: use default port number when none is specified
qemu-nbd.c:  use IANA-assigned port number: 10809

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Christoph Hellwig
581b9e29f3 raw-posix: handle > 512 byte alignment correctly
Replace the hardcoded handling of 512 byte alignment with bs->buffer_alignment
to handle larger sector size devices correctly.

Note that we can not rely on it to be initialize in bdrv_open, so deal
with the worst case there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-21 15:39:42 +02:00
Kevin Wolf
a655211ac6 vvfat: Use cache=unsafe
The qcow file used for write support in vvfat is a temporary file,
so we can use cache=unsafe there. Without this, write support is just
too slow to be of any use.

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
2010-09-21 15:39:42 +02:00
Kevin Wolf
9217e26f43 vvfat: Fix double free for opening the image rw
Allocation and deallocation of bs->opaque is not in the control of a
block driver. Therefore it should not set bs->opaque to a data structure
used by another bs, or closing the image will lead to a double free.

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
2010-09-21 15:39:42 +02:00
Kevin Wolf
ac48e389d0 vvfat: Fix segfault on write to read-only disk
vvfat tries to set the readonly flag in its open function, but nowadays
this is overwritted with the readonly=... command line option. Check in
bdrv_write if the vvfat was opened read-only and return an error in this
case.

Without this check, vvfat tries to access the qcow bs, which is NULL
without enabled write support.

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
2010-09-21 15:39:42 +02:00