Commit Graph

294 Commits

Author SHA1 Message Date
Stefan Hajnoczi
77a5a0001b qed: support for growing images
The .bdrv_truncate() operation resizes images and growing is easy to
implement in QED.  Simply check that the new size is valid and then
update the image_size header field to reflect the new size.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-18 14:39:15 +02:00
Stefan Hajnoczi
6f321e93ab qed: Periodically flush and clear need check bit
One strategy to limit the startup delay of consistency check when
opening image files is to ensure that the file is marked dirty for as
little time as possible.

QED currently marks the image dirty when the first allocating write
request is issued and clears the dirty bit again when the image is
cleanly closed.  In practice that means the image is marked dirty for
most of a guest's lifetime and prone to being in a dirty state upon
crash or power failure.

It is safe to clear the dirty bit after all allocating write requests
have completed and a flush has been performed.  This patch adds a timer
after the last allocating write request completes.  When the timer fires
it will flush and then clear the dirty bit.  The timer is set to 5
seconds and is cancelled upon arrival of a new allocating write request.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-18 14:38:46 +02:00
Stefan Weil
a1c7273b82 Fix typos in comments and code (occured -> occurred and related)
The code changed here is an unused data type name (evt_flush_occurred).

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-05-08 10:02:18 +01:00
Stefan Weil
ebabb67a17 Fix typo in code and comments
Replace writeable -> writable

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-05-06 08:19:25 +01:00
Nick Thomas
d2d979c628 NBD: Avoid leaking a couple of strings when the NBD device is closed
Signed-off-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-05-03 11:29:21 +02:00
Stefan Hajnoczi
19dfc44a94 qed: Fix consistency check on 32-bit hosts
The qed_bytes_to_clusters() function is normally used with size_t
lengths.  Consistency check used it with file size length and therefore
failed on 32-bit hosts when the image file is 4 GB or more.

Make qed_bytes_to_clusters() explicitly 64-bit and update consistency
check to keep 64-bit cluster counts.

Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-27 16:21:00 +02:00
Mitnick Lyu
2d56a546a7 vpc.c: Use get_option_parameter() does the search
Use get_option_parameter() to instead of duplicating the loop, and
use BDRV_SECTOR_SIZE to instead of 512

Signed-off-by: Mitnick Lyu <mitnick.lyu@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-13 12:31:41 +02:00
Anthony Liguori
21df65b644 qed: Add support for zero clusters
Zero clusters are similar to unallocated clusters except instead of reading
their value from a backing file when one is available, the cluster is always
read as zero.

This implements read support only.  At this stage, QED will never write a
zero cluster.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-13 12:06:41 +02:00
Nick Thomas
33897dc7d6 NBD device: Separate out parsing configuration and opening sockets.
We also change the way the file parameter is parsed so IPv6 IP
addresses can be used, e.g.: "drive=nbd:[::1]:5000"

Signed-off-by: Nick Thomas <nick@bytemark.co.uk>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-04-07 13:51:48 +02:00
Stefan Weil
4ff9786c67 Fix trivial "endianness bugs"
Replace endianess -> endianness.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-03 21:42:57 +02:00
Michael Tokarev
8cffde7329 get rid of private bitmap functions in block/sheepdog.c, use generic ones
qemu now has generic bitmap functions,
so don't redefine them in sheepdog.c,
use common header instead.  A small cleanup.

Here's only one function which is actually
used in sheepdog and gets replaced with
a generic one (simplified):

- static inline int test_bit(int nr, const volatile unsigned long *addr)
+ static inline int test_bit(int nr, const unsigned long *addr)
 {
-  return ((1UL << (nr % BITS_PER_LONG))
            & ((unsigned long*)addr)[nr / BITS_PER_LONG])) != 0;
+  return 1UL & (addr[nr / BITS_PER_LONG] >> (nr & (BITS_PER_LONG-1)));
 }

The body is equivalent, but the argument is not: there's
"volatile" in there.  Why it is used for - I'm not sure.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Acked-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2011-04-01 22:23:06 +02:00
Stefan Weil
5614c188c6 block/qcow: Don't ignore immediate read/write and other failures
This patch is similar to 171e3d6b99
which fixed qcow2:

Returning -EIO is far from optimal, but at least it's an error code.

In addition to read/write failures, -EIO is also returned when
decompress_cluster failed.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-15 13:21:14 +01:00
Stefan Weil
40a892b78c block/vdi: Don't ignore immediate read/write failures
This patch is similar to 171e3d6b99
which fixed qcow2:

Returning -EIO is far from optimal, but at least it's an error code.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-03-15 13:21:14 +01:00
Kevin Wolf
16fde5f2c2 qcow2: Fix order in L2 table COW
When copying L2 tables (this happens only with internal snapshots), the order
wasn't completely safe, so that after a crash you could end up with a L2 table
that has too low refcount, possibly leading to corruption in the long run.

This patch puts the operations in the right order: First allocate the new
L2 table and replace the reference, and only then decrease the refcount of the
old table.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-10 13:24:29 +01:00
Kevin Wolf
10b758e85c qed: Report error for unsupported features
Instead of just returning -ENOTSUP, generate a more detailed error.

Unfortunately we don't have a helpful text for features that we don't know yet,
so just print the feature mask. It might be useful at least if someone asks for
help.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
Acked-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-02-10 13:23:59 +01:00
Kevin Wolf
e8cdcec123 qcow2: Report error for version > 2
The qcow2 driver is now declared responsible for any QCOW image that has
version 2 or greater (before this, version 3 would be detected as raw).

For everything newer than version 2, an error is reported.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Anthony Liguori <aliguori@us.ibm.com>
2011-02-10 13:23:56 +01:00
Kevin Wolf
8af3648843 qcow2: Fix error handling for reading compressed clusters
When reading a compressed cluster failed, qcow2 falsely returned success.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
2011-02-10 13:23:44 +01:00
Kevin Wolf
3ab4c7e92d qcow2: Fix error handling for immediate backing file read failure
Requests could return success even though they failed when bdrv_aio_readv
returned NULL for a backing file read.

Reported-by: Chunqiang Tang <ctang@us.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-10 13:23:44 +01:00
Chunqiang Tang
e0d9c6f937 QCOW2: bug fix - read base image beyond its size
This patch fixes the following bug in QCOW2. For a QCOW2 image that is larger
than its base image, when handling a read request straddling over the end of the
base image, the QCOW2 driver attempts to read beyond the end of the base image
and the request would fail.

This bug was found by Fast Virtual Disk (FVD)'s fully automated testing tool.
The following test triggered the bug.

dd if=/dev/zero of=/var/ramdisk/truth.raw count=0 bs=1 seek=1098561536
dd if=/dev/zero of=/var/ramdisk/zero-500M.raw count=0 bs=1 seek=593099264
./qemu-img create -f qcow2 -ocluster_size=65536,backing_fmt=blksim -b /var/ramdisk/zero-500M.raw /var/ramdisk/test.qcow2 1098561536
./qemu-io --auto --seed=30477694 --truth=/var/ramdisk/truth.raw --format=qcow2 --test=blksim:/var/ramdisk/test.qcow2 --verify_write=true --compare_before=false --compare_after=true --round=100000 --parallel=100 --io_size=10485760 --fail_prob=0 --cancel_prob=0 --instant_qemubh=true

Signed-off-by: Chunqiang Tang <ctang@us.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-10 13:23:44 +01:00
Stefan Weil
4f3669ea5b block/vdi: Fix wrong size in conditionally used memset, memcmp
Error report from cppcheck:
block/vdi.c:122: error: Using sizeof for array given as function argument returns the size of pointer.
block/vdi.c:128: error: Using sizeof for array given as function argument returns the size of pointer.

Fix both by setting the correct size.

The buggy code is only used when QEMU is build without uuid support.
The bug is not critical, so there is no urgent need to apply it to
old versions of QEMU.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-02-07 10:07:25 +01:00
Kevin Wolf
e1a7107f2d qcow2: Really use cache=unsafe for image creation
For cache=unsafe we also need to set BDRV_O_CACHE_WB, otherwise we have some
strange unsafe writethrough mode.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2011-02-07 09:44:22 +01:00
Blue Swirl
1869a65385 qcow2-refcount: remove write-only variables
Variables l2_modified and l2_size are not really used, remove them.
Spotted by GCC 4.6.0:
  CC    block/qcow2-refcount.o
/src/qemu/block/qcow2-refcount.c: In function 'qcow2_update_snapshot_refcount':
/src/qemu/block/qcow2-refcount.c:708:37: error: variable 'l2_modified' set but not used [-Werror=unused-but-set-variable]
/src/qemu/block/qcow2-refcount.c:708:9: error: variable 'l2_size' set but not used [-Werror=unused-but-set-variable]

CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2011-01-31 10:05:34 +01:00
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