Commit Graph

38804 Commits

Author SHA1 Message Date
Alberto Garcia
2693310ecc qcow2: use an LRU algorithm to replace entries from the L2 cache
The current algorithm to evict entries from the cache gives always
preference to those in the lowest positions. As the size of the cache
increases, the chances of the later elements of being removed decrease
exponentially.

In a scenario with random I/O and lots of cache misses, entries in
positions 8 and higher are rarely (if ever) evicted. This can be seen
even with the default cache size, but with larger caches the problem
becomes more obvious.

Using an LRU algorithm makes the chances of being removed from the
cache independent from the position.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:01 +02:00
Alberto Garcia
baf07d60f5 qcow2: simplify qcow2_cache_put() and qcow2_cache_entry_mark_dirty()
Since all tables are now stored together, it is possible to obtain
the position of a particular table directly from its address, so the
operation becomes O(1).

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:01 +02:00
Alberto Garcia
72e80b8901 qcow2: use one single memory block for the L2/refcount cache tables
The qcow2 L2/refcount cache contains one separate table for each cache
entry. Doing one allocation per table adds unnecessary overhead and it
also requires us to store the address of each table separately.

Since the size of the cache is constant during its lifetime, it's
better to have an array that contains all the tables using one single
allocation.

In my tests measuring freshly created caches with sizes 128MB (L2) and
32MB (refcount) this uses around 10MB of RAM less.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:01 +02:00
Fam Zheng
13c4941cdd vmdk: Fix overflow if l1_size is 0x20000000
Richard Jones caught this bug with afl fuzzer.

In fact, that's the only possible value to overflow (extent->l1_size =
0x20000000) l1_size:

l1_size = extent->l1_size * sizeof(long) => 0x80000000;

g_try_malloc returns NULL because l1_size is interpreted as negative
during type casting from 'int' to 'gsize', which yields a enormous
value. Hence, by coincidence, we get a "not too bad" behavior:

qemu-img: Could not open '/tmp/afl6.img': Could not open
'/tmp/afl6.img': Cannot allocate memory

Values larger than 0x20000000 will be refused by the validation in
vmdk_add_extent.

Values smaller than 0x20000000 will not overflow l1_size.

Cc: qemu-stable@nongnu.org
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:01 +02:00
Fam Zheng
5e82a31eb9 vmdk: Fix next_cluster_sector for compressed write
This fixes the bug introduced by commit c6ac36e (vmdk: Optimize cluster
allocation).

Sometimes, write_len could be larger than cluster size, because it
contains both data and marker.  We must advance next_cluster_sector in
this case, otherwise the image gets corrupted.

Cc: qemu-stable@nongnu.org
Reported-by: Antoni Villalonga <qemu-list@friki.cat>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:00 +02:00
Christoph Hellwig
aacd5650c6 nvme: support NVME_VOLATILE_WRITE_CACHE feature
The SCSI emulation in the Linux NVMe driver really wants to know
if a device has a volatile write cache.  Given that qemu has moved
away from a model where we report the backing store WCE bit to
one where the WCE bit is supposed to be part of the migratable
guest-visible state we always return 1 here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:00 +02:00
Kevin Wolf
ecbda7a225 qcow2: Flush pending discards before allocating cluster
Before a freed cluster can be reused, pending discards for this cluster
must be processed.

The original assumption was that this was not a problem because discards
are only cached during discard/write zeroes operations, which are
synchronous so that no concurrent write requests can cause cluster
allocations.

However, the discard/write zeroes operation itself can allocate a new L2
table (and it has to in order to put zero flags there), so make sure we
can cope with the situation.

This fixes https://bugs.launchpad.net/bugs/1349972.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-05-22 17:08:00 +02:00
Peter Maydell
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Fri May 22 10:00:53 2015 BST using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"

* remotes/stefanha/tags/block-pull-request: (38 commits)
  block: get_block_status: use "else" when testing the opposite condition
  qemu-iotests: Test unaligned sub-block zero write
  block: Fix NULL deference for unaligned write if qiov is NULL
  Revert "block: Fix unaligned zero write"
  block: align bounce buffers to page
  block: minimal bounce buffer alignment
  block: return EPERM on writes or discards to read-only devices
  configure: Add workaround for ccache and clang
  configure: silence glib unknown attribute __alloc_size__
  configure: factor out supported flag check
  configure: handle clang -nopie argument warning
  block/parallels: improve image writing performance further
  block/parallels: optimize linear image expansion
  block/parallels: add prealloc-mode and prealloc-size open paramemets
  block/parallels: delay writing to BAT till bdrv_co_flush_to_os
  block/parallels: create bat_entry_off helper
  block/parallels: improve image reading performance
  iotests, parallels: check for incorrectly closed image in tests
  block/parallels: implement incorrect close detection
  block/parallels: implement parallels_check method of block driver
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-22 13:25:40 +01:00
Peter Maydell
f5790c3bc8 Revert "target-alpha: Add vector implementation for CMPBGE"
This reverts commit 32ad48abd7.

Unfortunately the SSE2 code here fails to compile on some versions
of gcc:
 target-alpha/int_helper.c:77:24: error: invalid operands to binary >=
 (have '__vector(16) unsigned char' and '__vector(16) unsigned char')

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-22 12:30:13 +01:00
Peter Maydell
27e1259a69 Rewrite fp exceptions
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Merge remote-tracking branch 'remotes/rth/tags/pull-axp-20150521' into staging

Rewrite fp exceptions

# gpg: Signature made Thu May 21 18:35:52 2015 BST using RSA key ID 4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"

* remotes/rth/tags/pull-axp-20150521:
  target-alpha: Add vector implementation for CMPBGE
  target-alpha: Rewrite helper_zapnot
  target-alpha: Raise IOV from CVTQL
  target-alpha: Suppress underflow from CVTTQ if DNZ
  target-alpha: Raise EXC_M_INV properly for fp inputs
  target-alpha: Disallow literal operand to 1C.30 to 1C.37
  target-alpha: Implement WH64EN
  target-alpha: Fix integer overflow checking insns
  target-alpha: Fix cvttq vs inf
  target-alpha: Fix cvttq vs large integers
  target-alpha: Raise IOV from CVTTQ
  target-alpha: Set EXC_M_SWC for exceptions from /S insns
  target-alpha: Set fpcr_exc_status even for disabled exceptions
  target-alpha: Tidy FPCR representation
  target-alpha: Set PC correctly for floating-point exceptions
  target-alpha: Forget installed round mode after MT_FPCR
  target-alpha: Rename floating-point subroutines
  target-alpha: Move VAX helpers to a new file

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-05-22 10:06:33 +01:00
Paolo Bonzini
a53f1a95f9 block: get_block_status: use "else" when testing the opposite condition
A bit of Boolean algebra (and common sense) tells us that the
second "if" here is looking for blocks that are not allocated.
This is the opposite of the "if" that sets BDRV_BLOCK_ALLOCATED,
and thus it can use an "else".

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1431599702-10431-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Fam Zheng
ab53c44718 qemu-iotests: Test unaligned sub-block zero write
Test zero write in byte range 512~1024 for 4k alignment.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1431522721-3266-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Fam Zheng
9eeb6dd1b2 block: Fix NULL deference for unaligned write if qiov is NULL
For zero write, callers pass in NULL qiov (qemu-io "write -z" or
scsi-disk "write same").

Commit fc3959e466 fixed bdrv_co_write_zeroes which is the common case
for this bug, but it still exists in bdrv_aio_write_zeroes. A simpler
fix would be in bdrv_co_do_pwritev which is the NULL dereference point
and covers both cases.

So don't access it in bdrv_co_do_pwritev in this case, use three aligned
writes.

[Initialize ret to 0 in bdrv_co_do_zero_pwritev() to avoid uninitialized
variable warning with gcc 4.9.2.
--Stefan]

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1431522721-3266-3-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Fam Zheng
d01c07f222 Revert "block: Fix unaligned zero write"
This reverts commit fc3959e466.

The core write code already handles the case, so remove this
duplication.

Because commit 61007b316 moved the touched code from block.c to
block/io.c, the change is manually reverted.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1431522721-3266-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Denis V. Lunev
459b4e6612 block: align bounce buffers to page
The following sequence
    int fd = open(argv[1], O_RDWR | O_CREAT | O_DIRECT, 0644);
    for (i = 0; i < 100000; i++)
            write(fd, buf, 4096);
performs 5% better if buf is aligned to 4096 bytes.

The difference is quite reliable.

On the other hand we do not want at the moment to enforce bounce
buffering if guest request is aligned to 512 bytes.

The patch changes default bounce buffer optimal alignment to
MAX(page size, 4k). 4k is chosen as maximal known sector size on real
HDD.

The justification of the performance improve is quite interesting.
From the kernel point of view each request to the disk was split
by two. This could be seen by blktrace like this:
  9,0   11  1     0.000000000 11151  Q  WS 312737792 + 1023 [qemu-img]
  9,0   11  2     0.000007938 11151  Q  WS 312738815 + 8 [qemu-img]
  9,0   11  3     0.000030735 11151  Q  WS 312738823 + 1016 [qemu-img]
  9,0   11  4     0.000032482 11151  Q  WS 312739839 + 8 [qemu-img]
  9,0   11  5     0.000041379 11151  Q  WS 312739847 + 1016 [qemu-img]
  9,0   11  6     0.000042818 11151  Q  WS 312740863 + 8 [qemu-img]
  9,0   11  7     0.000051236 11151  Q  WS 312740871 + 1017 [qemu-img]
  9,0    5  1     0.169071519 11151  Q  WS 312741888 + 1023 [qemu-img]
After the patch the pattern becomes normal:
  9,0    6  1     0.000000000 12422  Q  WS 314834944 + 1024 [qemu-img]
  9,0    6  2     0.000038527 12422  Q  WS 314835968 + 1024 [qemu-img]
  9,0    6  3     0.000072849 12422  Q  WS 314836992 + 1024 [qemu-img]
  9,0    6  4     0.000106276 12422  Q  WS 314838016 + 1024 [qemu-img]
and the amount of requests sent to disk (could be calculated counting
number of lines in the output of blktrace) is reduced about 2 times.

Both qemu-img and qemu-io are affected while qemu-kvm is not. The guest
does his job well and real requests comes properly aligned (to page).

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1431441056-26198-3-git-send-email-den@openvz.org
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Denis V. Lunev
4196d2f030 block: minimal bounce buffer alignment
The patch introduces new concept: minimal memory alignment for bounce
buffers. Original so called "optimal" value is actually minimal required
value for aligment. It should be used for validation that the IOVec
is properly aligned and bounce buffer is not required.

Though, from the performance point of view, it would be better if
bounce buffer or IOVec allocated by QEMU will be aligned stricter.

The patch does not change any alignment value yet.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1431441056-26198-2-git-send-email-den@openvz.org
CC: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
Paolo Bonzini
eaf5fe2dd4 block: return EPERM on writes or discards to read-only devices
This is the behavior in the operating system, for example Linux's
blkdev_write_iter has the following:

        if (bdev_read_only(I_BDEV(bd_inode)))
                return -EPERM;

This does not apply to opening a device for read/write, when the
device only supports read-only operation.  In this case any of
EACCES, EPERM or EROFS is acceptable depending on why writing is
not possible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1431013548-22492-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
John Snow
fd0e60530f configure: Add workaround for ccache and clang
Test if ccache is interfering with semantic analysis of macros,
disable its habit of trying to compile already pre-processed
versions of code if so. ccache attempts to save time by compiling
pre-processed versions of code, but this disturbs clang's static
analysis enough to produce false positives.

ccache allows us to disable this feature, opting instead to
compile the original version instead of its preprocessed version.
This makes ccache much slower for cache misses, but at least it
becomes usable with QEMU/clang.

This workaround only activates for users using ccache AND clang,
and only if their configuration is observed to be producing warnings.
You may need to clear your ccache for builds started without -Werror,
as those may continue to produce warnings from the cache.

Thanks to Peter Eisentraut for his writeup on the issue:
http://peter.eisentraut.org/blog/2014/12/01/ccache-and-clang-part-3/

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427324259-1481-5-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
John Snow
bbbf2e04e5 configure: silence glib unknown attribute __alloc_size__
The glib headers use GCC attributes.  Unfortunately the __GNUC__ and
__GNUC_MINOR__ version macros are also defined by clang, but clang
doesn't support the same attributes as GCC.

clang 3.5.0 does not support the __alloc_size__ attribute:

  c047507a9a

The following warning is produced:

  gstrfuncs.h:257:44: warning: unknown attribute '__alloc_size__' ignored [-Wunknown-attributes]
        G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(2);
          gmacros.h:67:45: note: expanded from macro 'G_GNUC_ALLOC_SIZE'
                #define G_GNUC_ALLOC_SIZE(x) __attribute__((__alloc_size__(x)))

This patch checks whether glib headers cause warnings and disables
-Wunknown-attributes if it is able to.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427324259-1481-4-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:33 +01:00
John Snow
93b2586922 configure: factor out supported flag check
Factor out the function that checks if a compiler
flag is supported or not.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427324259-1481-3-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Stefan Hajnoczi
e4a7b344df configure: handle clang -nopie argument warning
gcc 4.9.2 treats -nopie as an error:

  cc: error: unrecognized command line option ‘-nopie’

clang 3.5.0 treats -nopie as a warning:

  clang: warning: argument unused during compilation: '-nopie'

The causes ./configure to fail with clang:

  ERROR: configure test passed without -Werror but failed with -Werror.

Make the -nopie test use -Werror so that compile_prog works for both gcc
and clang.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427324259-1481-2-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
ddd2ef2ce8 block/parallels: improve image writing performance further
Try to perform IO for the biggest continuous block possible.
All blocks abscent in the image are accounted in the same type
and preallocation is made for all of them at once.

The performance for sequential write is increased from 200 Mb/sec to
235 Mb/sec on my SSD HDD.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-28-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
19f5dc1591 block/parallels: optimize linear image expansion
Plain image expansion spends a lot of time to update image file size.
This seriously affects the performance. The following simple test
  qemu_img create -f parallels -o cluster_size=64k ./1.hds 64G
  qemu_io -n -c "write -P 0x11 0 1024M" ./1.hds
could be improved if the format driver will pre-allocate some space
in the image file with a reasonable chunk.

This patch preallocates 128 Mb using bdrv_write_zeroes, which should
normally use fallocate() call inside. Fallback to older truncate()
could be used as a fallback using image open options thanks to the
previous patch.

The benefit is around 15%.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Karan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-27-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
d61790112f block/parallels: add prealloc-mode and prealloc-size open paramemets
This is preparational commit for tweaks in Parallels image expansion.
The idea is that enlarge via truncate by one data block is slow. It
would be much better to use fallocate via bdrv_write_zeroes and
expand by some significant amount at once.

Original idea with sequential file writing to the end of the file without
fallocate/truncate would be slower than this approach if the image is
expanded with several operations:
- each image expanding means file metadata update, i.e. filesystem
  journal write. Truncate/write to newly truncated space update file
  metadata twice thus truncate removal helps. With fallocate call
  inside bdrv_write_zeroes file metadata is updated only once and
  this should happen infrequently thus this approach is the best one
  for the image expansion
- tail writes are ordered, i.e. the guest IO queue could not be sent
  immediately to the host introducing additional IO delays

This patch just adds proper parameters into BDRVParallelsState and
performs options parsing in parallels_open.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-26-git-send-email-den@openvz.org
CC: Roman Kagan <rkagan@parallels.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
0d31c7c200 block/parallels: delay writing to BAT till bdrv_co_flush_to_os
The idea is that we do not need to immediately sync BAT to the image as
from the guest point of view there is a possibility that IO is lost
even in the physical controller until flush command was finished.
bdrv_co_flush_to_os is exactly the right place for this purpose.

Technically the patch uses loaded BAT data as a cache and performs
actual on-disk metadata updates in parallels_co_flush_to_os callback.

This patch speed ups
  qemu-img create -f parallels -o cluster_size=64k ./1.hds 64G
  qemu-io -f parallels -c "write -P 0x11 0 1024k" 1.hds
writing from 50-60 Mb/sec to 80-90 Mb/sec on rotational media and
from 160 Mb/sec to 190 Mb/sec on SSD disk.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-25-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
2d68e22e94 block/parallels: create bat_entry_off helper
calculate offset of the BAT entry in the image file.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-24-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
6953d92078 block/parallels: improve image reading performance
Try to perform IO for the biggest continuous block possible.
The performance for sequential read is increased from 220 Mb/sec to
360 Mb/sec for continous image on my SSD HDD.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-23-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
a6be831e99 iotests, parallels: check for incorrectly closed image in tests
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-22-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
6dd6b9f144 block/parallels: implement incorrect close detection
The software driver must set inuse field in Parallels header to
0x746F6E59 when the image is opened in read-write mode. The presence of
this magic in the header on open forces image consistency check.

There is an unfortunate trick here. We can not check for inuse in
parallels_check as this will happen too late. It is possible to do
that for simple check, but during the fix this would always report
an error as the image was opened in BDRV_O_RDWR mode. Thus we save
the flag in BDRVParallelsState for this.

On the other hand, nothing should be done to clear inuse in
parallels_check. Generic close will do the job right.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-21-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
49ad646731 block/parallels: implement parallels_check method of block driver
The check is very simple at the moment. It calculates necessary stats
and fix only the following errors:
- space leak at the end of the image. This would happens due to
  preallocation
- clusters outside the image are zeroed. Nothing else could be done here

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-20-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
23d6bd3bd1 block/parallels: move parallels_open/probe to the very end of the file
This will help to avoid forward declarations for upcoming parallels_check

Some very obvious formatting fixes were made to the moved code to make
checkpatch happy.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-19-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
9eae9cca95 block/parallels: read parallels image header and BAT into single buffer
This metadata cache would allow to properly batch BAT updates to disk
in next patches. These updates will be properly aligned to avoid
read-modify-write transactions on block level.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-18-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
dd97cdc064 block/parallels: keep BAT bitmap data in little endian in memory
This will allow to use this data as buffer to BAT update directly
without any intermediate buffers.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-17-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
555cc9d9fc block/parallels: create bat2sect helper
deduplicate copy/paste arithmetcs

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-16-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
369f7de9d5 block/parallels: rename catalog_ names to bat_
BAT means 'block allocation table'. Thus this name is clean and shorter
on writing.

Some obvious formatting fixes in the old code were made to make checkpatch
happy.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-15-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
cc5690f20f parallels: change copyright information in the image header
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-14-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
ca9c4e0675 iotests, parallels: test for newly created parallels image via qemu-img
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-13-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:32 +01:00
Denis V. Lunev
74cf6c5026 block/parallels: support parallels image creation
Do not even care to create WithoutFreeSpace image, it is obsolete.
Always create WithouFreSpacExt one.

The code also does not spend a lot of efforts to fill cylinders and
heads fields, they are not used actually in a real life neither in
QEMU nor in Parallels products.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-12-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
50ffd8fd3c iotests, parallels: test for write into Parallels image
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-11-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
5a41e1fa95 block/parallels: _co_writev callback for Parallels format
Support write on Parallels images. The code is almost the same as one
in the previous patch implemented scatter-gather IO for read.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-10-git-send-email-den@openvz.org
CC: Roman Kagan <rkagan@parallels.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
d0e61ce56d block/parallels: mark parallels format driver as zero inited
From the guest point of view unallocated blocks are zeroed.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-9-git-send-email-den@openvz.org
CC: Roman Kagan <rkagan@parallels.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
912f31281a block/parallels: replace magic constants 4, 64 with proper sizeofs
simple purification..

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-8-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
481fb9cf18 block/parallels: provide _co_readv routine for parallels format driver
Main approach is taken from qcow2_co_readv.

The patch drops coroutine lock for the duration of IO operation and
peforms normal scatter-gather IO using standard QEMU backend.

The patch also adds comment about locking considerations in the driver.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-7-git-send-email-den@openvz.org
CC: Roman Kagan <rkagan@parallels.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Roman Kagan
dd3bed16ff block/parallels: add get_block_status
Implement VFS method for get_block_status to Parallels format driver.

qemu_co_mutex_lock is not necessary yet (the driver is read-only) but
will be necessary very soon when write will be supported.

Signed-off-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1430207220-24458-6-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Roman Kagan
9de9da17d8 block/parallels: read up to cluster end in one go
Teach parallels_read() to do reads in coarser granularity than just a
single sector: if requested, read up to the cluster end in one go.

Signed-off-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1430207220-24458-5-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Roman Kagan
2944256997 block/parallels: switch to bdrv_read
Switch the .bdrv_read method implementation from using bdrv_pread() to
bdrv_read() on the underlying file, since the latter is subject to i/o
throttling while the former is not.

Besides, since bdrv_read() operates in sectors rather than bytes, adjust
the helper functions to do so too.

Signed-off-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1430207220-24458-4-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
0789890467 block/parallels: rename parallels_header to ParallelsHeader
this follows QEMU coding convention

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1430207220-24458-3-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Denis V. Lunev
d134cf73b1 iotests, parallels: quote TEST_IMG in 076 test to be path-safe
suggested by Jeff Cody

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1430207220-24458-2-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-05-22 09:37:31 +01:00
Richard Henderson
32ad48abd7 target-alpha: Add vector implementation for CMPBGE
While conditionalized on SSE2, it's a "portable" gcc generic vector
implementation, which could be enabled on other hosts.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-05-21 10:34:18 -07:00
Richard Henderson
8d8d324e34 target-alpha: Rewrite helper_zapnot
This form produces significantly smaller code on x86_64.

Signed-off-by: Richard Henderson <rth@twiddle.net>
2015-05-21 10:33:36 -07:00