Commit Graph

1863 Commits

Author SHA1 Message Date
Denis V. Lunev
d50d822219 block/raw-posix: call plain fallocate in handle_aiocb_write_zeroes
There is a possibility that we are extending our image and thus writing
zeroes beyond the end of the file. In this case we do not need to care
about the hole to make sure that there is no data in the file under
this offset (pre-condition to fallocate(0) to work). We could simply call
fallocate(0).

This improves the performance of writing zeroes even on really old
platforms which do not have even FALLOC_FL_PUNCH_HOLE.

Before the patch do_fallocate was used when either
CONFIG_FALLOCATE_PUNCH_HOLE or CONFIG_FALLOCATE_ZERO_RANGE are defined.
Now the story is different. CONFIG_FALLOCATE is defined when Linux
fallocate is defined, posix_fallocate is completely different story
(CONFIG_POSIX_FALLOCATE). CONFIG_FALLOCATE is mandatory prerequite
for both CONFIG_FALLOCATE_PUNCH_HOLE and CONFIG_FALLOCATE_ZERO_RANGE
thus we are on the safe side.

CC: Max Reitz <mreitz@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
CC: Fam Zheng <famz@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:20 +01:00
Denis V. Lunev
b953f07500 block: use fallocate(FALLOC_FL_ZERO_RANGE) in handle_aiocb_write_zeroes
This efficiently writes zeroes on Linux if the kernel is capable enough.
FALLOC_FL_ZERO_RANGE correctly handles all cases, including and not
including file expansion.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
CC: Fam Zheng <famz@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:20 +01:00
Denis V. Lunev
37cc9f7f68 block/raw-posix: refactor handle_aiocb_write_zeroes a bit
move code dealing with a block device to a separate function. This will
allow to implement additional processing for ordinary files.

Please note, that xfs_code has been moved before checking for
s->has_write_zeroes as xfs_write_zeroes does not touch this flag inside.
This makes code a bit more consistent.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
CC: Fam Zheng <famz@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:20 +01:00
Denis V. Lunev
0b99171230 block/raw-posix: create do_fallocate helper
The pattern
    do {
        if (fallocate(s->fd, mode, offset, len) == 0) {
            return 0;
        }
    } while (errno == EINTR);
    ret = translate_err(-errno);
will be commonly useful in next patches. Create helper for it.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
CC: Fam Zheng <famz@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:20 +01:00
Denis V. Lunev
1486df0e31 block/raw-posix: create translate_err helper to merge errno values
actually the code
    if (ret == -ENODEV || ret == -ENOSYS || ret == -EOPNOTSUPP ||
        ret == -ENOTTY) {
        ret = -ENOTSUP;
    }
is present twice and will be added a couple more times. Create helper
for this.

CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Peter Lieven <pl@kamp.de>
CC: Fam Zheng <famz@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:20 +01:00
Jeff Cody
cdf9634bdf block: vhdx - force FileOffsetMB field to '0' for certain block states
The v1.0.0 spec calls out PAYLOAD_BLOCK_ZERO FileOffsetMB field as being
'reserved'.  In practice, this means that Hyper-V will fail to read a
disk image with PAYLOAD_BLOCK_ZERO block states with a FileOffsetMB
value other than 0.

The other states that indicate a block that is not there
(PAYLOAD_BLOCK_UNDEFINED, PAYLOAD_BLOCK_NOT_PRESENT,
 PAYLOAD_BLOCK_UNMAPPED) have multiple options for what FileOffsetMB may
be set to, and '0' is explicitly called out as an option.

For all the above states, we will also just set the FileOffsetMB value
to 0.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a9fe92f53f07e6ab1693811e4312c0d1e958500b.1421787566.git.jcody@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-01-23 12:41:32 -05:00
Jeff Cody
9a29e18f7d block: update string sizes for filename,backing_file,exact_filename
The string field entries 'filename', 'backing_file', and
'exact_filename' in the BlockDriverState struct are defined as 1024
bytes.

However, many places that use these values accept a maximum of PATH_MAX
bytes, so we have a mixture of 1024 byte and PATH_MAX byte allocations.
This patch makes the BlockDriverStruct field string sizes match usage.

This patch also does a few fixes related to the size that needs to
happen now:

    * the block qapi driver is updated to use PATH_MAX bytes
    * the qcow and qcow2 drivers have an additional safety check
    * the block vvfat driver is updated to use PATH_MAX bytes
      for the size of backing_file, for systems where PATH_MAX is < 1024
      bytes.
    * qemu-img uses PATH_MAX rather than 1024.  These instances were not
      changed to be dynamically allocated, however, as the extra
      temporary 3K in stack usage for qemu-img does not seem worrisome.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:06 +01:00
Jeff Cody
1d33936ea8 block: mirror - change string allocation to 2-bytes
The backing_filename string in mirror_run() is only used to check
for a NULL string, so we don't need to allocate 1024 bytes (or, later,
PATH_MAX bytes), when we only need to copy the first 2 characters.

We technically only need 1 byte, as we are just checking for NULL, but
since backing_filename[] is populated by bdrv_get_backing_filename(), a
string size of 1 will always only return '\0';

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:06 +01:00
Jeff Cody
564d64bdde block: qapi - move string allocation from stack to the heap
Rather than declaring 'backing_filename2' on the stack in
bdrv_query_image_info(), dynamically allocate it on the heap.

Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:06 +01:00
Jeff Cody
fe2065629a block: vmdk - move string allocations from stack to the heap
Functions 'vmdk_parse_extents' and 'vmdk_create' allocate several
PATH_MAX sized arrays on the stack.  Make these dynamically allocated.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:05 +01:00
Jeff Cody
395a22fae0 block: vmdk - make ret variable usage clear
Keep the variable 'ret' something that is returned by the function it is
defined in.  For the return value of 'sscanf', use a more meaningful
variable name.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:05 +01:00
Max Reitz
8dd93d9339 qcow2: Add two more unalignment checks
This adds checks for unaligned L2 table offsets and unaligned data
cluster offsets (actually the preallocated offsets for zero clusters) to
the zero cluster expansion function.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-23 18:17:05 +01:00
Paolo Bonzini
66552b894b coroutine: drop qemu_coroutine_adjust_pool_size
This is not needed anymore.  The new TLS-based algorithm is adaptive.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417518350-6167-7-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-01-13 13:43:29 +00:00
Fam Zheng
c29c1dd312 qmp: Add command 'blockdev-backup'
Similar to drive-backup, but this command uses a device id as target
instead of creating/opening an image file.

Also add blocker on target bs, since the target is also a named device
now.

Add check and report error for bs == target which became possible but is
an illegal case with introduction of blockdev-backup.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-3-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-01-13 11:47:56 +00:00
Vladimir Sementsov-Ogievskiy
c4237dfa63 block: fix spoiling all dirty bitmaps by mirror and migration
Mirror and migration use dirty bitmaps for their purposes, and since
commit [block: per caller dirty bitmap] they use their own bitmaps, not
the global one. But they use old functions bdrv_set_dirty and
bdrv_reset_dirty, which change all dirty bitmaps.

Named dirty bitmaps series by Fam and Snow are affected: mirroring and
migration will spoil all (not related to this mirroring or migration)
named dirty bitmaps.

This patch fixes this by adding bdrv_set_dirty_bitmap and
bdrv_reset_dirty_bitmap, which change concrete bitmap. Also, to prevent
such mistakes in future, old functions bdrv_(set,reset)_dirty are made
static, for internal block usage.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
CC: John Snow <jsnow@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: Denis V. Lunev <den@openvz.org>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417081246-3593-1-git-send-email-vsementsov@parallels.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-01-13 11:47:56 +00:00
Max Reitz
1085daf941 block/vmdk: Relative backing file for creation
When a vmdk image is created with a backing file, it is opened to check
whether it is indeed a vmdk file by letting qemu probe it. When doing
so, the backing filename is relative to the image's base directory so it
should be interpreted accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-13 11:47:56 +00:00
Max Reitz
9f07429e88 block: JSON filenames and relative backing files
When using a relative backing file name, qemu needs to know the
directory of the top image file. For JSON filenames, such a directory
cannot be easily determined (e.g. how do you determine the directory of
a qcow2 BDS directly on top of a quorum BDS?). Therefore, do not allow
relative filenames for the backing file of BDSs only having a JSON
filename.

Furthermore, BDS::exact_filename should be used whenever possible. If
BDS::filename is not equal to BDS::exact_filename, the former will
always be a JSON object.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-01-13 11:47:56 +00:00
Peter Wu
debfb917a4 block/iscsi: fix uninitialized variable
'ret' was never initialized in the success path.

Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-03 09:22:13 +01:00
Paolo Bonzini
82595da8de linux-aio: simplify removal of completed iocbs from the list
There is no need to do another O(n) pass on the list; the iocb to
split the list at is already available through the array we passed to
io_submit.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-6-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Paolo Bonzini
de35464461 linux-aio: drop return code from laio_io_unplug and ioq_submit
These are unused.

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-5-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Paolo Bonzini
8455ce053a linux-aio: rename LaioQueue idx field to "n"
It does not identify an index in an array anymore.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-4-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Paolo Bonzini
43f2376e09 linux-aio: track whether the queue is blocked
Avoid that unplug submits requests when io_submit reported that it
couldn't accept more; at the same time, try more io_submit calls if it
could handle the whole set of requests that were passed, so that the
"blocked" flag is reset as soon as possible.

After the previous patch, laio_submit already tried to avoid submitting
requests to a blocked queue, by comparing s->io_q.idx with "==" instead
of the more natural ">=".  Switch to the simpler expression now that we
have the "blocked" flag.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-3-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Paolo Bonzini
28b240877b linux-aio: queue requests that cannot be submitted
Keep a queue of requests that were not submitted; pass them to
the kernel when a completion is reported, unless the queue is
plugged.

The array of iocbs is rebuilt every time from scratch.  This
avoids keeping the iocbs array and list synchronized.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1418305950-30924-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:57:55 +00:00
Jeff Cody
85b712c9d5 block: vhdx - set .bdrv_has_zero_init to bdrv_has_zero_init_1
Now that new VHDX images will default to BAT block states of
PAYLOAD_BLOCK_ZERO, we can indicate that VHDX has zero init.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 5e582703e36450b9ca939e2e5c9fa3930030f7fe.1418018421.git.jcody@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 16:35:35 +00:00
Jeff Cody
30af51ce7f block: vhdx - change .vhdx_create default block state to ZERO
The VHDX spec specifies that the default new block state is
PAYLOAD_BLOCK_NOT_PRESENT for a dynamic VHDX image, and
PAYLOAD_BLOCK_FULLY_PRESENT for a fixed VHDX image.

However, in order to create space-efficient VHDX images with qemu-img
convert, it is desirable to be able to set has_zero_init to true for
VHDX.

There is currently an option when creating VHDX images, to use block
state ZERO for new blocks.  However, this currently defaults to 'off'.
In order to be able to eventually set has_zero_init to true for VHDX,
this needs to default to 'on'.

This patch changes the default to 'on', and provides some help
information to warn against setting it to 'off' when using qemu-img
convert.

[Max Reitz pointed out that a full stop was missing at the end of the
VHDX_BLOCK_OPT_ZERO option help text.  I have added it.
--Stefan]

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 85164899eacc86e150c3ceba793cf93b398dedd7.1418018421.git.jcody@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 15:42:49 +00:00
Jeff Cody
a9d1e9daa5 block: vhdx - update PAYLOAD_BLOCK_UNMAPPED value to match 1.00 spec
The 0.95 VHDX spec defined PAYLOAD_BLOCK_UNMAPPED to be 5.  The 1.00
VHDX spec redefines PAYLOAD_BLOCK_UNMAPPED to be 3 instead.

The original value of 5 is now an undefined state in the spec, but it
should be safe to treat it the same and return zeros for data read.
This way, we can maintain compatibility with any images out in the wild
that may have been created in accordance to the 0.95 spec.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 8a4d2da73a8dbc04cde62bea782fc09ff84b1cf1.1418018421.git.jcody@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 15:42:22 +00:00
Jeff Cody
0571df44a1 block: vhdx - remove redundant comments
Minor cleanup.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: e8718ae3fd3e40a527e46a00e394973fbaab4d53.1418018421.git.jcody@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 15:42:22 +00:00
Gonglei
9281dbe653 block/rbd: fix memory leak
Variable local_err going out of scope
leaks the storage it points to.

Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Amos Kong <akong@redhat.com>
Message-id: 1417674851-6248-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 13:16:56 +00:00
Max Reitz
5c98415b2a vmdk: Fix error for JSON descriptor file names
If vmdk blindly tries to use path_combine() using bs->file->filename as
the base file name, this will result in a bad error message for JSON
file names when calling bdrv_open(). It is better to only try
bs->file->exact_filename; if that is empty, bs->file->filename will be
useless for path_combine() and an error should be emitted (containing
bs->file->filename because desc_file_path (which is
bs->file->exact_filename) is empty).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1417615043-26174-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-12-12 13:14:10 +00:00
Fam Zheng
d899d2e248 vmdk: Set errp on failures in vmdk_open_vmdk4
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1417649314-13704-7-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Fam Zheng
9aeecbbc62 vmdk: Remove unnecessary initialization
It will be assigned to the return value of vmdk_read_desc.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1417649314-13704-6-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Fam Zheng
03c3359dfc vmdk: Check descriptor file length when reading it
Since a too small file cannot be a valid VMDK image, and also since the
buffer's first 4 bytes will be unconditionally examined by
vmdk_open_sparse, let's error out the small file case to be clear.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Message-id: 1417649314-13704-5-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Fam Zheng
73b7bcad43 vmdk: Clean up descriptor file reading
Zeroing a buffer that will be filled right after is not necessary, and
allocating a power of two + 1 is naughty.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1417649314-13704-4-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Fam Zheng
8a3e0bc370 vmdk: Fix comment to match code of extent lines
commit 04d542c8b (vmdk: support vmfs files) added support of VMFS extent
type but the comment above the changed code is left out. Update the
comment so they are consistent.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Message-id: 1417649314-13704-3-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Fam Zheng
e5dc64b8ff vmdk: Use g_random_int to generate CID
This replaces two "time(NULL)" invocations with "g_random_int()".
According to VMDK spec, CID "is a random 32‐bit value updated the first
time the content of the virtual disk is modified after the virtual disk
is opened". Using "seconds since epoch" is just a "lame way" to generate
it, and not completely safe because of the low precision.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Don Koch <dkoch@verizon.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1417649314-13704-2-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Jeff Cody
625fa9fe6f block: remove BLOCK_OPT_NOCOW from vpc_create_opts
In commit fef6070, the need for NOCOW was removed from the vpc driver,
as we removed the the posix calls.  However, the BLOCK_OPT_NOCOW was not
removed from vpc_create_opts.  This was a mistake - remove the opt from
there as well.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 8ba076fa725fed681cde7d8afc4fb239ae06a9c6.1417620301.git.jcody@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:21 +01:00
Jeff Cody
0d0d7f47b4 block: remove BLOCK_OPT_NOCOW from vdi_create_opts
In commit 7074786, the need for NOCOW was removed from the vdi driver,
as we removed the the posix calls.  However, the BLOCK_OPT_NOCOW was not
removed from vdi_create_opts.  This was a mistake - remove the opt from
there as well.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: e189364de11929d8fa04722f5d845de0a9834d44.1417620301.git.jcody@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:20 +01:00
Max Reitz
01212d4ed6 block/raw-posix: Fix ret in raw_open_common()
The return value must be negative on error; there is one place in
raw_open_common() where errp is set, but ret remains 0. Fix it.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:20 +01:00
Max Reitz
6a69b9620a qcow2: Respect bdrv_truncate() error
bdrv_truncate() may fail and qcow2_write_compressed() should return the
error code in that case.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:20 +01:00
Max Reitz
3b5e14c76a qcow2: Flushing the caches in qcow2_close may fail
qcow2_cache_flush() may fail; if one of the caches failed to be flushed
successfully to disk in qcow2_close() the image should not be marked
clean, and we should emit a warning.

This breaks the (qcow2-specific) iotests 026, 071 and 089; change their
output accordingly.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:20 +01:00
Max Reitz
11c89769dc qcow2: Prevent numerical overflow
In qcow2_alloc_cluster_offset(), *num is limited to
INT_MAX >> BDRV_SECTOR_BITS by all callers. However, since remaining is
of type uint64_t, we might as well cast *num to that type before
performing the shift.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:20 +01:00
Max Reitz
fd752801ae block/nfs: Add create_opts
The nfs protocol driver is capable of creating images, but did not
specify any creation options. Fix it.

A way to test this issue is the following:

$ qemu-img create -f nfs nfs://127.0.0.1/foo.qcow2 64M

Without this patch, it segfaults. With this patch, it does not. However,
this is not something that should really work; qemu-img should check
whether the parameter for the -f option (and -O for convert) is indeed a
format, and error out if it is not. Therefore, I am not making it an
iotest.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:19 +01:00
Max Reitz
1bcb15cf77 block/vvfat: qcow driver may not be found
Although virtually impossible right now, bdrv_find_format("qcow") may
fail. The vvfat block driver should heed that case.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:19 +01:00
Max Reitz
ef8104378c block: Omit bdrv_find_format for essential drivers
We can always assume raw, file and qcow2 being available; so do not use
bdrv_find_format() to locate their BlockDriver objects but statically
reference the respective objects.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:19 +01:00
Max Reitz
5f535a941e block: Make essential BlockDriver objects public
There are some block drivers which are essential to QEMU and may not be
removed: These are raw, file and qcow2 (as the default non-raw format).
Make their BlockDriver objects public so they can be directly referenced
throughout the block layer without needing to call bdrv_find_format()
and having to deal with an error at runtime, while the real problem
occurred during linking (where raw, file or qcow2 were not linked into
qemu).

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:19 +01:00
Paolo Bonzini
a56ebc6ba4 block: do not use get_clock()
Use the external qemu-timer API instead.

No one else should be calling cpu_get_clock(), get_clock() and
get_clock_realtime() directly; they are internal functions and they
should be confined to qemu-timer.c and cpus.c (where the icount
implementation resides).  All accesses should go through
qemu_clock_get_ns.

Cc: kwolf@redhat.com
Cc: stefanha@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1417010463-3527-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:13 +01:00
Kevin Wolf
2ebafc854d qcow2: Fix header extension size check
After reading the extension header, offset is incremented, but not
checked against end_offset any more. This way an integer overflow could
happen when checking whether the extension end is within the allowed
range, effectively disabling the check.

This patch adds the missing check and a test case for it.

Cc: qemu-stable@nongnu.org
Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1416935562-7760-2-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:13 +01:00
Kevin Wolf
38f3ef574b raw: Prohibit dangerous writes for probed images
If the user neglects to specify the image format, QEMU probes the
image to guess it automatically, for convenience.

Relying on format probing is insecure for raw images (CVE-2008-2004).
If the guest writes a suitable header to the device, the next probe
will recognize a format chosen by the guest.  A malicious guest can
abuse this to gain access to host files, e.g. by crafting a QCOW2
header with backing file /etc/shadow.

Commit 1e72d3b (April 2008) provided -drive parameter format to let
users disable probing.  Commit f965509 (March 2009) extended QCOW2 to
optionally store the backing file format, to let users disable backing
file probing.  QED has had a flag to suppress probing since the
beginning (2010), set whenever a raw backing file is assigned.

All of these additions that allow to avoid format probing have to be
specified explicitly. The default still allows the attack.

In order to fix this, commit 79368c8 (July 2010) put probed raw images
in a restricted mode, in which they wouldn't be able to overwrite the
first few bytes of the image so that they would identify as a different
image. If a write to the first sector would write one of the signatures
of another driver, qemu would instead zero out the first four bytes.
This patch was later reverted in commit 8b33d9e (September 2010) because
it didn't get the handling of unaligned qiov members right.

Today's block layer that is based on coroutines and has qiov utility
functions makes it much easier to get this functionality right, so this
patch implements it.

The other differences of this patch to the old one are that it doesn't
silently write something different than the guest requested by zeroing
out some bytes (it fails the request instead) and that it doesn't
maintain a list of signatures in the raw driver (it calls the usual
probe function instead).

Note that this change doesn't introduce new breakage for false positive
cases where the guest legitimately writes data into the first sector
that matches the signatures of an image format (e.g. for nested virt):
These cases were broken before, only the failure mode changes from
corruption after the next restart (when the wrong format is probed) to
failing the problematic write request.

Also note that like in the original patch, the restrictions only apply
if the image format has been guessed by probing. Explicitly specifying a
format allows guests to write anything they like.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1416497234-29880-8-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:13 +01:00
Max Reitz
2c28b21f7c block: Add blk_add_close_notifier() for BB
Adding something like a "delete notifier" to a BlockBackend would not
make much sense, because whoever is interested in registering there will
probably hold a reference to that BlockBackend; therefore, the notifier
will never be called (or only when the notifiee already relinquished its
reference and thus most probably is no longer interested in that
notification).

Therefore, this patch just passes through the close notifier interface
of the root BDS. This will be called when the device is ejected, for
instance, and therefore does make sense.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:12 +01:00
Max Reitz
2019ba0a01 block: Add AioContextNotifier functions to BB
Because all BlockDriverStates behind a single BlockBackend reside in a
single AioContext, it is fine to just pass these functions
(blk_add_aio_context_notifier() and blk_remove_aio_context_notifier())
through to the root BlockDriverState.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:12 +01:00
Max Reitz
2bb0dce762 block: Lift more functions into BlockBackend
There are already some blk_aio_* functions, so we might as well have
blk_co_* functions (as far as we need them). This patch adds
blk_co_flush(), blk_co_discard(), and also blk_invalidate_cache() (which
is not a blk_co_* function but is needed nonetheless).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416309679-333-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:12 +01:00
Max Reitz
8779441b1b blkdebug: Simplify and improve filename generation
Instead of actually recreating the options from scratch, just reuse the
options given for creating the BDS, which are the configuration file
name and additional options. In case there are no additional options we
can thus create a plain filename.

This obviously results in a different output for qemu-iotest 099 which
exactly tests this filename generation. Fix it up as well.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1415697825-26678-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:31:11 +01:00
Kevin Wolf
9e193c5a65 block/qapi: Add cache information to query-block
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-12-10 10:31:09 +01:00
Fam Zheng
f71eaa74c0 qmp: Add optional switch "query-nodes" in query-blockstats
This bool option will allow query all the node names. It iterates all
the BDSes that are assigned a name, also in this case don't query up the
backing chain.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:25:29 +01:00
Fam Zheng
4875a77950 block: Include "node-name" if present in query-blockstats
Node name is a better identifier of BDS.

We will want to query statistics of a BDS node buried in the BDS graph,
so reporting the node's name if there is one will do the trick.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-12-10 10:25:29 +01:00
Kevin Wolf
24bf10dac3 Revert "qemu-img info: show nocow info"
This reverts commit 000c4dfff4.

The main reason for reverting this commit before the 2.2 release is that
it adds a QAPI interface that we don't want to keep: The 'nocow' flag
doesn't generally make sense for block nodes, but only for the raw-posix
driver. It should therefore be part of ImageInfoSpecific rather than
ImageInfo.

The commit contains more problems, but unlike the API stability issue
they wouldn't justify reverting it.

Conflicts:
	block/qapi.c

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-24 13:52:10 +01:00
Max Reitz
098ffa6674 block/raw-posix: Catch fsync() errors
fsync() may fail, and that case should be handled.

Reported-by: László Érsek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-18 12:09:00 +01:00
Max Reitz
731de38052 block/raw-posix: Only sync after successful preallocation
The loop which filled the file with zeroes may have been left early due
to an error. In that case, the fsync() should be skipped.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-18 12:09:00 +01:00
Max Reitz
39411cf3c3 block/raw-posix: Fix preallocating write() loop
write() may write less bytes than requested; in this case, the number of
bytes written is returned. This is the byte count we should be
subtracting from the number of bytes still to be written, and not the
byte count we requested to write.

Reported-by: László Érsek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-11-18 12:08:59 +01:00
Markus Armbruster
d1f06fe665 raw-posix: The SEEK_HOLE code is flawed, rewrite it
On systems where SEEK_HOLE in a trailing hole seeks to EOF (Solaris,
but not Linux), try_seek_hole() reports trailing data instead.

Additionally, unlikely lseek() failures are treated badly:

* When SEEK_HOLE fails, try_seek_hole() reports trailing data.  For
  -ENXIO, there's in fact a trailing hole.  Can happen only when
  something truncated the file since we opened it.

* When SEEK_HOLE succeeds, SEEK_DATA fails, and SEEK_END succeeds,
  then try_seek_hole() reports a trailing hole.  This is okay only
  when SEEK_DATA failed with -ENXIO (which means the non-trailing hole
  found by SEEK_HOLE has since become trailing somehow).  For other
  failures (unlikely), it's wrong.

* When SEEK_HOLE succeeds, SEEK_DATA fails, SEEK_END fails (unlikely),
  then try_seek_hole() reports bogus data [-1,start), which its caller
  raw_co_get_block_status() turns into zero sectors of data.  Could
  theoretically lead to infinite loops in code that attempts to scan
  data vs. hole forward.

Rewrite from scratch, with very careful comments.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2014-11-18 09:45:48 +01:00
Markus Armbruster
c4875e5b22 raw-posix: SEEK_HOLE suffices, get rid of FIEMAP
Commit 5500316 (May 2012) implemented raw_co_is_allocated() as
follows:

1. If defined(CONFIG_FIEMAP), use the FS_IOC_FIEMAP ioctl

2. Else if defined(SEEK_HOLE) && defined(SEEK_DATA), use lseek()

3. Else pretend there are no holes

Later on, raw_co_is_allocated() was generalized to
raw_co_get_block_status().

Commit 4f11aa8 (May 2014) changed it to try the three methods in order
until success, because "there may be implementations which support
[SEEK_HOLE/SEEK_DATA] but not [FIEMAP] (e.g., NFSv4.2) as well as vice
versa."

Unfortunately, we used FIEMAP incorrectly: we lacked FIEMAP_FLAG_SYNC.
Commit 38c4d0a (Sep 2014) added it.  Because that's a significant
speed hit, the next commit 7c159037 put SEEK_HOLE/SEEK_DATA first.

As you see, the obvious use of FIEMAP is wrong, and the correct use is
slow.  I guess this puts it somewhere between -7 "The obvious use is
wrong" and -10 "It's impossible to get right" on Rusty Russel's Hard
to Misuse scale[*].

"Fortunately", the FIEMAP code is used only when

* SEEK_HOLE/SEEK_DATA aren't defined, but CONFIG_FIEMAP is

  Uncommon.  SEEK_HOLE had no XFS implementation between 2011 (when it
  was introduced for ext4 and btrfs) and 2012.

* SEEK_HOLE/SEEK_DATA and CONFIG_FIEMAP are defined, but lseek() fails

  Unlikely.

Thus, the FIEMAP code executes rarely.  Makes it a nice hidey-hole for
bugs.  Worse, bugs hiding there can theoretically bite even on a host
that has SEEK_HOLE/SEEK_DATA.

I don't want to worry about this crap, not even theoretically.  Get
rid of it.

[*] http://ozlabs.org/~rusty/index.cgi/tech/2008-04-01.html

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2014-11-18 09:45:35 +01:00
Markus Armbruster
be2ebc6dad raw-posix: Fix comment for raw_co_get_block_status()
Missed in commit 705be72.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2014-11-18 09:44:02 +01:00
Fam Zheng
5f58330790 vmdk: Leave bdi intact if -ENOTSUP in vmdk_get_info
When extent types don't match, we return -ENOTSUP. In this case, be
polite to the caller and don't modify bdi.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1415938161-16217-1-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-14 09:20:45 +00:00
Max Reitz
d20418ee51 block/vdi: Limit maximum size even futher
The block layer read and write functions do not like requests which are
bigger than INT_MAX bytes. Since the VDI bmap is read and written in a
single operation, its size is therefore limited accordingly. This
reduces the maximum VDI image size supported by QEMU to half of what it
currently is (down to approximately 512 TB).

The VDI test 084 has to be adapted accordingly. Actually, one could
clearly see that it was broken from the "Could not open
'TEST_DIR/t.IMGFMT': Invalid argument" line for an image which was
supposed to work just fine.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
2014-11-09 23:39:50 +01:00
Peter Maydell
9a33c0c851 -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
 
 iQEcBAABAgAGBQJUV2wdAAoJEJykq7OBq3PIjcAH/29rl938ETw1wjXxYe3uH+R6
 K2yFEiPh9/cOJSH0mJ+gD8DZIN+iyR4eoQGP2s5ALFPcX3bkYxRLlUeYK0BCp883
 esc7gO6XPhLvTVqP0xgACRCdUwH2I0VTToDlHjXXZogyI/DuDX3gzWJufE3x1DGs
 WNTMOp5n/uYkWH3rI3DkInmbSddEz3pgX65a8BuYtw0V/RSeSRnHKDYHMygvJBRL
 EVfWRNeOIrZ730CyJry0t8ITjsZxiBDKXR5glNSwaIfQUfGkTSWi9YNSurNYkUDr
 aMS2rgvOVlrOUDKTHUj9oS3jgoGWcDtlk9E1MeSoyIptbRoMhdFVl1AUJZsrMJU=
 =Mfbu
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

# gpg: Signature made Mon 03 Nov 2014 11:50:53 GMT 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: (53 commits)
  block: declare blockjobs and dataplane friends!
  block: let commit blockjob run in BDS AioContext
  block: let mirror blockjob run in BDS AioContext
  block: let stream blockjob run in BDS AioContext
  block: let backup blockjob run in BDS AioContext
  block: add bdrv_drain()
  blockjob: add block_job_defer_to_main_loop()
  blockdev: add note that block_job_cb() must be thread-safe
  blockdev: acquire AioContext in blockdev_mark_auto_del()
  blockdev: acquire AioContext in do_qmp_query_block_jobs_one()
  block: acquire AioContext in generic blockjob QMP commands
  iotests: Expand test 061
  block/qcow2: Simplify shared L2 handling in amend
  block/qcow2: Make get_refcount() global
  block/qcow2: Implement status CB for amend
  qemu-img: Fix insignificant memleak
  qemu-img: Add progress output for amend
  block: Add status callback to bdrv_amend_options()
  block: qemu-iotest 107 supports NFS
  iotests: Add test for qcow2's bdrv_make_empty
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-11-03 18:34:09 +00:00
Peter Maydell
7135781f65 trivial patches for 2014-11-02
-----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1.4.12 (GNU/Linux)
 
 iQEcBAABAgAGBQJUVhuDAAoJEL7lnXSkw9fbOKMIAIE3XZMhar4Vmokb/K0DFbnh
 gy2z7iCe7vumLKiRSJX1LGmkFO3dwykw82JZQ1SVo0RdgguJ5dx1Abx1qDM1rojL
 jJT0pJ9zWPl4fTv38wCEfaysQHPdgwoH4826ga+MXnVS9XHRHHxuQ4vI01AK3oyQ
 4t6/wto9H8kF3n6ny7tz5WNZClsq7qbiIqw5nNCILQfSh/VBPwxQNBiWf/nYVMuY
 Ubk5noztZwH+hbiAQL5lAPz/HolcRwg1tzbR0dfmt8/aqO28rJhasG58JgtziI2y
 JSg4BwldqUQEgiHonArLfQDixjLtEEyL+fQSzZm02ixwcBpc/ADSyGDy2R1zpH8=
 =j1ga
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/mjt/tags/pull-trivial-patches-2014-11-02' into staging

trivial patches for 2014-11-02

# gpg: Signature made Sun 02 Nov 2014 11:54:43 GMT using RSA key ID A4C3D7DB
# gpg: Good signature from "Michael Tokarev <mjt@tls.msk.ru>"
# gpg:                 aka "Michael Tokarev <mjt@corpit.ru>"
# gpg:                 aka "Michael Tokarev <mjt@debian.org>"

* remotes/mjt/tags/pull-trivial-patches-2014-11-02: (23 commits)
  vdi: wrapped uuid_unparse() in #ifdef
  tap: fix possible fd leak in net_init_tap
  tap: do not close(fd) in net_init_tap_one
  target-i386: Remove unused model_features_t struct
  tap_int.h: remove repeating NETWORK_SCRIPT defines
  os-posix: reorder parent notification for -daemonize
  pidfile: stop making pidfile error a special case
  os-posix: replace goto again with a proper loop
  os-posix: use global daemon_pipe instead of cryptic fds[1]
  dump: Fix dump-guest-memory termination and use-after-close
  virtio-9p-proxy: improve error messages in connect_namedsocket()
  virtio-9p-proxy: fix error return in proxy_init()
  virtio-9p-proxy: Fix sockfd leak
  target-tricore: check return value before using it
  net/slirp: specify logbase for smbd
  Revert "os-posix: report error message when lock file failed"
  util: Improve os_mem_prealloc error message
  sparse: fix build
  target-arm: A64: remove redundant store
  target-xtensa: mark XtensaConfig structs as unused
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-11-03 14:55:17 +00:00
Stefan Hajnoczi
9e85cd5ce0 block: let commit blockjob run in BDS AioContext
The commit block job must run in the BlockDriverState AioContext so that
it works with dataplane.

Acquire the AioContext in blockdev.c so starting the block job is safe.
One detail here is that the bdrv_drain_all() must be moved inside the
aio_context_acquire() region so requests cannot sneak in between the
drain and acquire.

The completion code in block/commit.c must perform backing chain
manipulation and bdrv_reopen() from the main loop.  Use
block_job_defer_to_main_loop() to achieve that.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-11-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Stefan Hajnoczi
5a7e7a0bad block: let mirror blockjob run in BDS AioContext
The mirror block job must run in the BlockDriverState AioContext so that
it works with dataplane.

Acquire the AioContext in blockdev.c so starting the block job is safe.

Note that to_replace is treated separately from other BlockDriverStates
in that it does not need to be in the same AioContext.  Explicitly
acquire/release to_replace's AioContext when accessing it.

The completion code in block/mirror.c must perform BDS graph
manipulation and bdrv_reopen() from the main loop.  Use
block_job_defer_to_main_loop() to achieve that.

The bdrv_drain_all() call is not allowed outside the main loop since it
could lead to lock ordering problems.  Use bdrv_drain(bs) instead
because we have acquired the AioContext so nothing else can sneak in
I/O.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-10-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Stefan Hajnoczi
f3e69beb94 block: let stream blockjob run in BDS AioContext
The stream block job must run in the BlockDriverState AioContext so that
it works with dataplane.

The basics of acquiring the AioContext are easy in blockdev.c.

The tricky part is the completion code which drops part of the backing
file chain.  This must be done in the main loop where bdrv_unref() and
bdrv_close() are safe to call.  Use block_job_defer_to_main_loop() to
achieve that.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-9-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Stefan Hajnoczi
761731b180 block: let backup blockjob run in BDS AioContext
The backup block job must run in the BlockDriverState AioContext so that
it works with dataplane.

The basics of acquiring the AioContext are easy in blockdev.c.

The completion code in block/backup.c must call bdrv_unref() from the
main loop.  Use block_job_defer_to_main_loop() to achieve that.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-8-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Max Reitz
ecf58777c5 block/qcow2: Simplify shared L2 handling in amend
Currently, we have a bitmap for keeping track of which clusters have
been created during the zero cluster expansion process. This was
necessary because we need to properly increase the refcount for shared
L2 tables.

However, now we can simply take the L2 refcount and use it for the
cluster allocated for expansion. This will be the correct refcount and
therefore we don't have to remember that cluster having been allocated
any more.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Message-id: 1414404776-4919-7-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:49 +00:00
Max Reitz
44751917db block/qcow2: Make get_refcount() global
Reading the refcount of a cluster is an operation which can be useful in
all of the qcow2 code, so make that function globally available.

While touching this function, amend the comment describing the "addend"
parameter: It is (no longer, if it ever was) necessary to have it set to
-1 or 1; any value is fine.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Message-id: 1414404776-4919-6-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:49 +00:00
Max Reitz
4057a2b24a block/qcow2: Implement status CB for amend
The only really time-consuming operation potentially performed by
qcow2_amend_options() is zero cluster expansion when downgrading qcow2
images from compat=1.1 to compat=0.10, so report status of that
operation and that operation only through the status CB.

For this, approximate the progress as the number of L1 entries visited
during the operation.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Message-id: 1414404776-4919-5-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:49 +00:00
Max Reitz
7748543420 block: Add status callback to bdrv_amend_options()
Depending on the changed options and the image format,
bdrv_amend_options() may take a significant amount of time. In these
cases, a way to be informed about the operation's status is desirable.

Since the operation is rather complex and may fundamentally change the
image, implementing it as AIO or a coroutine does not seem feasible. On
the other hand, implementing it as a block job would be significantly
more difficult than a simple callback and would not add benefits other
than progress report to the amending operation, because it should not
actually be run as a block job at all.

A callback may not be very pretty, but it's very easy to implement and
perfectly fits its purpose here.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414404776-4919-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:48 +00:00
Max Reitz
d4a3238af5 qemu-img: Implement commit like QMP
qemu-img should use QMP commands whenever possible in order to ensure
feature completeness of both online and offline image operations. As
qemu-img itself has no access to QMP (since this would basically require
just everything being linked into qemu-img), imitate QMP's
implementation of block-commit by using commit_active_start() and then
waiting for the block job to finish.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1414159063-25977-9-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:48 +00:00
Max Reitz
b21c76529d block/mirror: Improve progress report
Instead of taking the total length of the block device as the block
job's length, use the number of dirty sectors. The progress is now the
number of sectors mirrored to the target block device. Note that this
may result in the job's length increasing during operation, which is
however in fact desirable.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414159063-25977-8-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:48 +00:00
Max Reitz
94054183da qcow2: Optimize bdrv_make_empty()
bdrv_make_empty() is currently only called if the current image
represents an external snapshot that has been committed to its base
image; it is therefore unlikely to have internal snapshots. In this
case, bdrv_make_empty() can be greatly sped up by emptying the L1 and
refcount table (while having the dirty flag set, which only works for
compat=1.1) and creating a trivial refcount structure.

If there are snapshots or for compat=0.10, fall back to the simple
implementation (discard all clusters).

[Applied s/clusters/cluster/ typo fix suggested by Eric Blake
--Stefan]

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1414159063-25977-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:48 +00:00
Max Reitz
491d27e2af qcow2: Implement bdrv_make_empty()
Implement this function by making all clusters in the image file fall
through to the backing file (by using the recently extended discard).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414159063-25977-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:48 +00:00
Max Reitz
808c4b6f30 qcow2: Allow "full" discard
Normally, discarded sectors should read back as zero. However, there are
cases in which a sector (or rather cluster) should be discarded as if
they were never written in the first place, that is, reading them should
fall through to the backing file again.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414159063-25977-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:47 +00:00
Max Reitz
d7f62751a1 raw-posix: raw_co_get_block_status() return value
Instead of generating the full return value thrice in try_fiemap(),
try_seek_hole() and as a fall-back in raw_co_get_block_status() itself,
generate the value only in raw_co_get_block_status().

While at it, also remove the pnum parameter from try_fiemap() and
try_seek_hole().

Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414148280-17949-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:47 +00:00
Max Reitz
e6d7ec32dd raw-posix: Fix raw_co_get_block_status() after EOF
As its comment states, raw_co_get_block_status() should unconditionally
return 0 and set *pnum to 0 for after EOF.

An assertion after lseek(..., SEEK_HOLE) tried to catch this case by
asserting that errno != -ENXIO (which would indicate a position after
the EOF); but it should be errno != ENXIO instead. Regardless of that,
there should be no such assertion at all. If bdrv_getlength() returned
an outdated value and the image has been resized outside of qemu,
lseek() will return with errno == ENXIO. Just return that value as an
error then.

Setting *pnum to 0 and returning 0 should not be done here, as in that
case we should update the device length as well. So, from qemu's
perspective, the file has not been resized; it's just that there was an
error querying sectors beyond a certain point (the actual file size).

Additionally, nb_sectors should be clamped against the image end. This
was probably not an issue if FIEMAP or SEEK_HOLE/SEEK_DATA worked, but
the fallback did not take this case into account.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1414148280-17949-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:47 +00:00
Richard W.M. Jones
f76faeda4b block/curl: Improve type safety of s->timeout.
qemu_opt_get_number returns a uint64_t, and curl_easy_setopt expects a
long (not an int).  There is no warning about the latter type error
because curl_easy_setopt uses a varargs argument.

Store the timeout (which is a positive number of seconds) as a
uint64_t.  Check that the number given by the user is reasonable.
Zero is permissible (meaning no timeout is enforced by cURL).

Cast it to long before calling curl_easy_setopt to fix the type error.

Example error message after this change has been applied:

$ ./qemu-img create -f qcow2 /tmp/test.qcow2 \
    -b 'json: { "file.driver":"https",
                "file.url":"https://foo/bar",
                "file.timeout":-1 }'
qemu-img: /tmp/test.qcow2: Could not open 'json: { "file.driver":"https", "file.url":"https://foo/bar", "file.timeout":-1 }': timeout parameter is too large or negative: Invalid argument

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 11:41:47 +00:00
Zhang Haoyu
3432a1929e snapshot: add bdrv_drain_all() to bdrv_snapshot_delete() to avoid concurrency problem
If there are still pending i/o while deleting snapshot,
because deleting snapshot is done in non-coroutine context, and
the pending i/o read/write (bdrv_co_do_rw) is done in coroutine context,
so it's possible to cause concurrency problem between above two operations.
Add bdrv_drain_all() to bdrv_snapshot_delete() to avoid this problem.

Signed-off-by: Zhang Haoyu <zhanghy@sangfor.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 201410211637596311287@sangfor.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:42 +00:00
Adam Crume
be21788495 rbd: Add support for bdrv_invalidate_cache
This fixes Ceph issue 2467: ttp://tracker.ceph.com/issues/2467

[Dropped return r in void function as suggested by Josh Durgin
<josh.durgin@inktank.com>.
--Stefan]

Signed-off-by: Adam Crume <adamcrume@gmail.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1412880272-3154-1-git-send-email-adamcrume@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
Denis V. Lunev
da725d0b0e block/parallels: fix access to not initialized memory in catalog_bitmap
found by valgrind.

Command: ./qemu-img convert -f parallels -O qcow2 1.hds 1.img
Invalid read of size 4
   at 0x17D0EF: parallels_co_read (parallels.c:357)
   by 0x11FEE4: bdrv_aio_rw_vector (block.c:4640)
   by 0x11FFBF: bdrv_aio_readv_em (block.c:4652)
   by 0x11F55F: bdrv_co_readv_em (block.c:4862)
   by 0x123428: bdrv_aligned_preadv (block.c:3056)
   by 0x1239FA: bdrv_co_do_preadv (block.c:3162)
   by 0x125424: bdrv_rw_co_entry (block.c:2706)
   by 0x155DD9: coroutine_trampoline (coroutine-ucontext.c:118)
   by 0x6975B6F: ??? (in /lib/x86_64-linux-gnu/libc-2.19.so)

The problem is that s->catalog_bitmap is allocated/filled as
gmalloc(s->catalog_size) thus index validity check must be
inclusive, i.e. index >= s->catalog_size is invalid.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1412759610-2257-4-git-send-email-den@openvz.org
CC: Jeff Cody <jcody@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
Peter Lieven
dc9e716369 block/iscsi: check for oversized requests
Cancel oversized requests early. They would generate
an iSCSI protocol error anyway; after having transferred
possibly a lot of data over the wire.

Suggested-By: Max Reitz <mreitz@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
Peter Lieven
3dab155154 block/iscsi: use sector_limits_lun2qemu throughout iscsi_refresh_limits
As Max pointed out there is a hidden cast from int64_t to int for all
limits. So use the newly introduced sector_limits_lun2qemu for all
limits received from the target.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
Peter Lieven
52f6fa1430 block/iscsi: set max_transfer_length
Copy the max_xfer_len from the BlockLimits VPD or use the
maximum value fitting in the CDB.

The helper function sector_limits_lun2qemu is introduced to convert
and cap the limits from the VPD to the maximum power of two fitting
in an integer; integer is the range for nb_sectors throughout
the block layer.

Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-11-03 09:48:41 +00:00
SeokYeon Hwang
f18a768efb vdi: wrapped uuid_unparse() in #ifdef
Wrapped uuid_unparse() in #ifdef to avoid "-Wunused-function"
on clang 3.4 or later.

Signed-off-by: SeokYeon Hwang <syeon.hwang@samsung.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-11-02 10:05:35 +03:00
Fam Zheng
c1d4096b0f iscsi: Refuse to open as writable if the LUN is write protected
Before, when a write protected iSCSI target is attached as scsi-disk
with BDRV_O_RDWR, we report it as writable, while in fact all writes
will fail.

One way to improve this is to report write protect flag as true to
guest, but a even better way is to refuse using a write protected LUN to
guest.

Target write protect flag is checked with a mode sense query.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-10-31 11:29:02 +01:00
Roger Pau Monne
3cad83075c block: char devices on FreeBSD are not behind a pager
Introduce a new flag to mark devices that require requests to be aligned and
replace the usage of BDRV_O_NOCACHE and O_DIRECT with this flag when
appropriate.

If a character device is used as a backend on a FreeBSD host set this flag
unconditionally.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2014-10-23 16:56:53 +02:00
Max Reitz
a1391444fe qcow2: Do not overflow when writing an L1 sector
While writing an L1 table sector, qcow2_write_l1_entry() copies the
respective range from s->l1_table to the local "buf" array. The size of
s->l1_table does not have to be a multiple of L1_ENTRIES_PER_SECTOR;
thus, limit the index which is used for copying all entries to the L1
size.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:02 +02:00
Max Reitz
17bd5f4727 qcow2: Drop REFCOUNT_SHIFT
With BDRVQcowState.refcount_block_bits, we don't need REFCOUNT_SHIFT
anymore.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:02 +02:00
Max Reitz
791230d8bb qcow2: Clean up after refcount rebuild
Because the old refcount structure will be leaked after having rebuilt
it, we need to recalculate the refcounts and run a leak-fixing operation
afterwards (if leaks should be fixed at all).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
c7c0681bc8 qcow2: Rebuild refcount structure during check
The previous commit introduced the "rebuild" variable to qcow2's
implementation of the image consistency check. Now make use of this by
adding a function which creates a completely new refcount structure
based solely on the in-memory information gathered before.

The old refcount structure will be leaked, however. This leak will be
dealt with in a follow-up commit.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
f307b2558f qcow2: Do not perform potentially damaging repairs
If a referenced cluster has a refcount of 0, increasing its refcount may
result in clusters being allocated for the refcount structures. This may
overwrite the referenced cluster, therefore we cannot simply increase
the refcount then.

In such cases, we can either try to replicate all the refcount
operations solely for the check operation, basing the allocations on the
in-memory refcount table; or we can simply rebuild the whole refcount
structure based on the in-memory refcount table. Since the latter will
be much easier, do that.

To prepare for this, introduce a "rebuild" boolean which should be set
to true whenever a fix is rather dangerous or too complicated using the
current refcount structures. Another example for this is refcount blocks
being referenced more than once.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
001c158def qcow2: Fix refcount blocks beyond image end
If the qcow2 check function detects a refcount block located beyond the
image end, grow the image appropriately. This cannot break anything and
is the logical fix for such a case.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
9696df219a qcow2: Reuse refcount table in calculate_refcounts()
We will later call calculate_refcounts multiple times, so reuse the
refcount table if possible.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
641bb63cd6 qcow2: Let inc_refcounts() resize the reftable
Now that the refcount table can be passed around by reference, do that
for inc_refcounts() (and subsequently check_refcounts_l1() and
check_refcounts_l2()) and use it for resizing it when a cluster after
the image end is encountered.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz
fef4d3d564 qcow2: Let inc_refcounts() return -errno
As of a future patch, inc_refcounts() will have to throw errors which
are generally signaled by returning -errno. Therefore, let it return an
integer which is either 0 for success or -errno and handle the -errno
case in all callers.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00