Commit graph

1001 commits

Author SHA1 Message Date
Paolo Bonzini 04d542c8b8 vmdk: support vmfs files
VMware ESX hosts also use different create and extent types for flat
files, respectively "vmfs" and "VMFS".  This is not documented, but it
can be found at http://kb.vmware.com/kb/10002511 (Recreating a missing
virtual machine disk (VMDK) descriptor file).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 15:35:58 +02:00
Fam Zheng daac8fdc68 vmdk: support vmfsSparse files
VMware ESX hosts use a variant of the VMDK3 format, identified by the
vmfsSparse create type ad the VMFSSPARSE extent type.

It has 16 KB grain tables (L2) and a variable-size grain directory (L1).
In addition, the grain size is always 512, but that is not a problem
because it is included in the header.

The format of the extents is documented in the VMDK spec.  The format
of the descriptor file is not documented precisely, but it can be
found at http://kb.vmware.com/kb/10026353 (Recreating a missing virtual
machine disk (VMDK) descriptor file for delta disks).

With these patches, vmfsSparse files only work if opened through the
descriptor file.  Data files without descriptor files, as far as I
could understand, are not supported by ESX.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>

--
v2: Rebase to patch 01.
    Change le64_to_cpu to le32_to_cpu.
    Rename vmdk_open_vmdk3 to vmdk_open_vmfs_sparse, which represents the
    current usage of this format.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 15:35:58 +02:00
Fam Zheng f6b61e54bd vmdk: fix L1 and L2 table size in vmdk3 open
VMDK3 header has the field l1dir_size, but vmdk_open_vmdk3 hardcoded the
value. This patch honors the header field.

And the L2 table size is 4096 according to VMDK spec[1], instead of
1 << 9 (512).

[1]:
http://www.vmware.com/support/developer/vddk/vmdk_50_technote.pdf?src=vmdk

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 15:35:58 +02:00
Fam Zheng b0651b8c24 vmdk: Move l1_size check into vmdk_add_extent()
This header check is common to VMDK3 and VMDK4, so move it into
vmdk_add_extent().

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 15:35:58 +02:00
Asias He 0d51b4debe block: Introduce bs->zero_beyond_eof
In 4146b46c42e0989cb5842e04d88ab6ccb1713a48 (block: Produce zeros when
protocols reading beyond end of file), we break qemu-iotests ./check
-qcow2 022. This happens because qcow2 temporarily sets ->growable = 1
for vmstate accesses (which are stored beyond the end of regular image
data).

We introduce the bs->zero_beyond_eof to allow qcow2_load_vmstate() to
disable ->zero_beyond_eof temporarily in addition to enable ->growable.

[Since the broken patch "block: Produce zeros when protocols reading
beyond end of file" has not been merged yet, I have applied this fix
*first* and will then apply the next patch to keep the tree bisectable.
-- Stefan]

Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 14:10:21 +02:00
Kevin Wolf 8ad1898cf1 qcow2: Change default for new images to compat=1.1
By the time that qemu 1.7 will be released, enough time will have passed
since qemu 1.1, which is the first version to understand version 3
images, that changing the default shouldn't hurt many people any more
and the benefits of using the new format outweigh the pain.

qemu-iotests already runs with compat=1.1 by default.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-21 14:41:09 +02:00
Stefan Hajnoczi f2e5dca46b aio: drop io_flush argument
The .io_flush() handler no longer exists and has no users.  Drop the
io_flush argument to aio_set_fd_handler() and related functions.

The AioFlushEventNotifierHandler and AioFlushHandler typedefs are no
longer used and are dropped too.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi f0d3576599 block/ssh: drop return_true()
.io_flush() is no longer called so drop return_true().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi d6d94c6785 block/sheepdog: drop have_co_req() and aio_flush_request()
.io_flush() is no longer called so drop have_co_req() and
aio_flush_request().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi 5d289cc724 block/rbd: drop qemu_rbd_aio_flush_cb()
.io_flush() is no longer called so drop qemu_rbd_aio_flush_cb().
qemu_aio_count is unused now so drop it too.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi bed2e759eb block/nbd: drop nbd_have_request()
.io_flush() is no longer called so drop nbd_have_request().  We cannot
drop in_flight since it is still used by other block/nbd.c code.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi 94473d0c06 block/linux-aio: drop qemu_laio_completion_cb()
.io_flush() is no longer called so drop qemu_laio_completion_cb().  It
turns out that count is now unused so drop that too.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi 70ecdc6e4e block/iscsi: drop iscsi_process_flush()
.io_flush() is no longer called so drop iscsi_process_flush().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:52:19 +02:00
Stefan Hajnoczi 372835fbc3 block/gluster: drop qemu_gluster_aio_flush_cb()
Since .io_flush() is no longer called we do not need
qemu_gluster_aio_flush_cb() anymore.  It turns out that qemu_aio_count
is unused now and can be dropped.

Thanks to Bharata B Rao <bharata@linux.vnet.ibm.com> for catching a
build failure with CONFIG_GLUSTERFS_DISCARD, which has been fixed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:51:09 +02:00
Stefan Hajnoczi 0d1460226f block/curl: drop curl_aio_flush()
.io_flush() is no longer called so drop curl_aio_flush().  The acb[]
array that the function checks is still used in other parts of
block/curl.c.  Therefore we cannot remove acb[], it is needed.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:45:35 +02:00
Stefan Hajnoczi 88266f5aa7 block: stop relying on io_flush() in bdrv_drain_all()
If a block driver has no file descriptors to monitor but there are still
active requests, it can return 1 from .io_flush().  This is used to spin
during synchronous I/O.

Stop relying on .io_flush() and instead check
QLIST_EMPTY(&bs->tracked_requests) to decide whether there are active
requests.

This is the first step in removing .io_flush() so that event loops no
longer need to have the concept of synchronous I/O.  Eventually we may
be able to kill synchronous I/O completely by running everything in a
coroutine, but that is future work.

Note this patch moves bs->throttled_reqs initialization to bdrv_new() so
that bdrv_requests_pending(bs) can safely access it.  In practice bs is
g_malloc0() so the memory is already zeroed but it's safer to initialize
the queue properly.

We also need to fix up block/stream.c:close_unused_images() to prevent
traversing a dangling pointer while it rearranges the backing file
chain.  This is necessary since the new bdrv_drain_all() traverses the
backing file chain.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-19 15:45:34 +02:00
Paolo Bonzini 7748c1bd50 raw: add license header
Most of the block layer is under the BSD license, thus it is reasonable
to license block/raw.c the same way.  CCed people should ACK by replying
with a Signed-off-by line.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Jeff Cody <jcody@redhat.com>
Cc: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1375251592-2537-2-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-08-12 09:15:11 -05:00
Fam Zheng ca8804ced9 vmdk: rename num_gtes_per_gte to num_gtes_per_gt
num_gtes_per_gte is a historical typo, rename it to a more sensible
name. It means "number of GrainTableEntries per GrainTable".

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng bf81507de3 vmdk: use heap allocation for whole_grain
We should never grow the stack beyond 1 MB, otherwise we'll fall off the
end.  Thread stacks and coroutine stacks (1 MB) do not grow.
get_cluster_offset() allocates a big stack offset, it will fail for big
cluster images, change to heap allocated buffer.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng 2c43e43c8c vmdk: check l1 size before opening image
L1 table size is calculated from capacity, granularity and l2 table
size. If capacity is too big or later two are too small, the L1 table
will be too big to allocate in memory. Limit it to a reasonable range.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng f8ce04036e vmdk: check l2 table size when opening
header.num_gtes_per_gte determines size for L2 table. Check for too big
value before using it. Limit to 512M entries (2GB per one L2 table).

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng 8aa1331c09 vmdk: check granularity field in opening
Granularity is used to calculate the cluster size and allocate r/w
buffer. Check the value from image before using it, so we don't abort()
for unbounded memory allocation.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng e98768d437 vmdk: use unsigned values for on disk header fields
The size and offset fields are all non-negative values, use uint64_t for
them to avoid getting negative in memory value by int overflow.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Fam Zheng 5d8caa543c vmdk: Make VMDK3Header and VmdkGrainMarker QEMU_PACKED
It's best to make it consistent that all on disk structures are
QEMU_PACKED.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 15:27:32 +02:00
Liu Yuan e4f5c1bf8f sheepdog: add missing .bdrv_has_zero_init
Commit 3ac21627 changed the behaviour of bdrv_has_zero_init() to default
to 0. In the review for Sheepdog it turned out that enabling it is safe,
so that commit updated one BlockDriver definition of sheepdog to use
bdrv_has_zero_init_1, missed however that there are more BlockDrivers in
the driver. Fix these now.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Reviewed-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06 10:41:56 +02:00
Fam Zheng 8e50724313 vmdk: fix comment for vmdk_co_write_zeroes
The comment was truncated. Add the missing parts, especially explain why
we need zero_dry_run.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-08-02 18:07:04 +04:00
Richard W.M. Jones f5075224d6 block/iscsi.c: Fix printf format error.
The error on armv7hl was:

block/iscsi.c: In function ‘is_request_lun_aligned’:
block/iscsi.c:251:26: error: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘int64_t’ [-Werror=format=]
                          iscsilun->block_size, sector_num, nb_sectors);
                          ^

This also splits the long line to comply with qemu coding guidelines.

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-08-02 18:02:48 +04:00
Peter Maydell 2440a2c3df block/sheepdog: Rename 'dprintf' to 'DPRINTF'
'dprintf' is the name of a POSIX standard function so we should not be
stealing it for our debug macro. Rename to 'DPRINTF' (in line with
a number of other source files.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Acked-by: Richard Henderson <rth@twiddle.net>
Acked-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1375100199-13934-2-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-07-29 19:33:53 -05:00
Anthony Liguori eddbf0ab9d Merge remote-tracking branch 'stefanha/block' into staging
# By Stefan Hajnoczi (4) and others
# Via Stefan Hajnoczi
* stefanha/block:
  dataplane: refuse to start if device is already in use
  dataplane: enable virtio-blk x-data-plane=on live migration
  migration: fix spice migration
  migration: notify migration state before starting thread
  block: Repair the throttling code.
  gluster: Add image resize support

Message-id: 1375112172-24863-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-07-29 11:33:48 -05:00
Paolo Bonzini 42ec24e285 gluster: Add image resize support
Implement .bdrv_truncate in GlusterFS block driver so that GlusterFS backend
can support image resizing.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Tested-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-29 17:07:37 +02:00
Stefan Weil 52f350227f misc: Fix new typos in comments and strings
All these typos were found by codespell.

sould -> should
emperical -> empirical
intialization -> initialization
successfuly -> successfully
gaurantee -> guarantee

Fix also another error (before before) in the same context.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-07-27 11:22:54 +04:00
Ian Main fc5d3f8432 Implement sync modes for drive-backup.
This patch adds sync-modes to the drive-backup interface and
implements the FULL, NONE and TOP modes of synchronization.

FULL performs as before copying the entire contents of the drive
while preserving the point-in-time using CoW.
NONE only copies new writes to the target drive.
TOP copies changes to the topmost drive image and preserves the
point-in-time using CoW.

For sync mode TOP are creating a new target image using the same backing
file as the original disk image.  Then any new data that has been laid
on top of it since creation is copied in the main backup_run() loop.
There is an extra check in the 'TOP' case so that we don't bother to copy
all the data of the backing file as it already exists in the target.
This is where the bdrv_co_is_allocated() is used to determine if the
data exists in the topmost layer or below.

Also any new data being written is intercepted via the write_notifier
hook which ends up calling backup_do_cow() to copy old data out before
it gets overwritten.

For mode 'NONE' we create the new target image and only copy in the
original data from the disk image starting from the time the call was
made.  This preserves the point in time data by only copying the parts
that are *going to change* to the target image.  This way we can
reconstruct the final image by checking to see if the given block exists
in the new target image first, and if it does not, you can get it from
the original image.  This is basically an optimization allowing you to
do point-in-time snapshots with low overhead vs the 'FULL' version.

Since there is no old data to copy out the loop in backup_run() for the
NONE case just calls qemu_coroutine_yield() which only wakes up after
an event (usually cancel in this case).  The rest is handled by the
before_write notifier which again calls backup_do_cow() to write out
the old data so it can be preserved.

Signed-off-by: Ian Main <imain@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 22:01:31 +02:00
Kevin Wolf 64aa99d3e0 qcow2: Use dashes instead of underscores in options
This is what QMP wants to use. The options haven't been enabled in any
release yet, so we're still free to change them.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-26 21:59:56 +02:00
Peter Lieven a23fdf3559 block/raw: add .bdrv_get_info
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-19 15:27:37 +08:00
Peter Lieven 8bf9344ad6 block/raw: add bdrv_co_write_zeroes
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-19 12:29:21 +08:00
Fam Zheng 78f27bd02c block: fix vvfat error path for enable_write_target
s->qcow and s->qcow_filename are allocated but not freed on error. Fix the
possible leaks, remove unnecessary check for bdrv_new(), propagate ret code of
bdrv_create() and also the one of enable_write_target().

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-19 12:29:21 +08:00
Bharata B Rao 0c14fb47ec gluster: Add discard support for GlusterFS block driver.
Implement bdrv_aio_discard for gluster.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-19 12:29:21 +08:00
Peter Lieven 0777b5dde4 iscsi: factor out sector conversions
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-17 17:01:41 +02:00
Peter Lieven 91bea4e2bb iscsi: assert that sectors are aligned to LUN blocksize
if the blocksize of an iSCSI LUN is bigger than the BDRV_SECTOR_SIZE
it is possible that sector_num or nb_sectors are not correctly
aligned.

to avoid corruption we fail requests which are misaligned.

Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-17 17:01:41 +02:00
Peter Lieven 7e4d5a9f94 iscsi: remove support for misaligned nb_sectors in aio_readv
this hask is not working (anymore). support for misaligned offsets should
be handled at the block layer.

Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-17 17:01:41 +02:00
Peter Lieven d3bda7bc16 iscsi: fix -ENOSPC in iscsi_create()
the -ENOPSC case did not work due to the missing goto.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-17 17:00:28 +02:00
Ronnie Sahlberg 0a53f01074 Fix iSCSI crash on SG_IO with an iovector
Don't assume that SG_IO is always invoked with a simple buffer,
check the iovec_count and if it is >= 1 then we need to pass an array
of iovectors to libiscsi instead of just a plain buffer.

Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-17 17:00:26 +02:00
Kevin Wolf 98289620e0 block: Don't parse protocol from file.filename
One of the major reasons for doing something new for -blockdev and
blockdev-add was that the old block layer code parses filenames instead
of just taking them literally. So we should really leave it untouched
when it's passing using the new interfaces (like -drive
file.filename=...).

This allows opening relative file names that contain a colon.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2013-07-15 09:49:00 +02:00
Fam Zheng 3494d65027 curl: refuse to open URL from HTTP server without range support
CURL driver requests partial data from server on guest IO req. For HTTP
and HTTPS, it uses "Range: ***" in requests, and this will not work if
server not accepting range. This patch does this check when open.

 * Removed curl_size_cb, which is not used: On one hand it's registered to
   libcurl as CURLOPT_WRITEFUNCTION, instead of CURLOPT_HEADERFUNCTION,
   which will get called with *data*, not *header*. On the other hand the
   s->len is assigned unconditionally later.

   In this gone function, the sscanf for "Content-Length: %zd", on
   (void *)ptr, which is not guaranteed to be zero-terminated, is
   potentially a security bug. So this patch fixes it as a side-effect. The
   bug is reported as: https://bugs.launchpad.net/qemu/+bug/1188943
   (Note the bug is marked "private" so you might not be able to see it)

 * Introduced curl_header_cb, which is used to parse header and mark the
   server as accepting range if "Accept-Ranges: bytes" line is seen from
   response header. If protocol is HTTP or HTTPS, but server response has
   no not this support, refuse to open this URL.

Note that python builtin module SimpleHTTPServer is an example of not
supporting range, if you need to test this driver, get a better server
or use internet URLs.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-05 09:40:18 +02:00
Fam Zheng da7a50f938 vmdk: Implement .bdrv_has_zero_init
Depending on the subformat, has_zero_init queries underlying storage for
flat extent. If it has a flat extent and its underlying storage doesn't
have zero init, return 0. Otherwise return 1.

Aligns the operator assignments.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-05 09:40:18 +02:00
Peter Lieven 3ac216270a block: change default of .has_zero_init to 0
.has_zero_init defaults to 1 for all formats and protocols.

this is a dangerous default since this means that all
new added drivers need to manually overwrite it to 0 if
they do not ensure that a device is zero initialized
after bdrv_create().

if a driver needs to explicitly set this value to
1 its easier to verify the correctness in the review process.

during review of the existing drivers it turned out
that ssh and gluster had a wrong default of 1.
both protocols support host_devices as backend
which are not by default zero initialized. this
wrong assumption will lead to possible corruption
if qemu-img convert is used to write to such a backend.

vpc and vmdk also defaulted to 1 altough they support
fixed respectively flat extends. this has to be addresses
in separate patches. both formats as well as the mentioned
ssh and gluster are turned to the default of 0 with this
patch for safety.

a similar problem with the wrong default existed for
iscsi most likely because the driver developer did
oversee the default value of 1.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 13:52:35 +02:00
Kevin Wolf 72c6cc94da vpc: Implement .bdrv_has_zero_init
Depending on the subformat, has_zero_init on VHD must behave like raw
and query the underlying storage (fixed) or like other sparse formats
that can always return 1 (dynamic, differencing).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 10:21:00 +02:00
Fam Zheng 8ed610a1c9 vmdk: remove wrong calculation of relative path
When creating image with backing file, the driver tries to calculate the
relative path from created image file to backing file, but the path
computation is incorrect. e.g.:

    $ qemu-img create -f vmdk -b vmdk-data-disk.vmdk vmdk-data-snapshot1
    Formatting 'vmdk-data-snapshot1', fmt=vmdk size=10737418240
    backing_file='vmdk-data-disk.vmdk' compat6=off zeroed_grain=off

    $ qemu-img info vmdk-data-snapshot1
    image: vmdk-data-snapshot1
    file format: vmdk
    virtual size: 10G (10737418240 bytes)
    disk size: 12K
->  backing file: disk.vmdk

The common part in file names, "vmdk-data-", is incorrectly forgotten by
relative_path(). As the VMDK specification has no restriction on
parentNameHint to be relative path, we simply remove this by using the
backing_file option.

Cc: qemu-stable@nongnu.org
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00
Kevin Wolf 8ab6feec2c gluster: Return bdrv_has_zero_init = 0
GlusterFS volumes can be backed by block devices, in which case
bdrv_create() doesn't make sure that the image is zeroed out. It is
currently not possibly to detect whether a given image is backed by a
file or a block device, and incorrectly assuming that it is zeroed
corrupts images during qemu-img convert, so let's err on the side of
caution and always return 0.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00
Richard W.M. Jones 0b3f21e6a9 block/ssh: Set bdrv_has_zero_init according to the file type.
If the remote is a regular file, set it to true (ie. reads of
uninitialized areas in a newly created file will return zeroes).
If we can't prove that, return false (a safe default).

Tested by adding a debugging print statement [not part of this commit]
and creating a remote file and a remote block device:

  $ ./qemu-img create ssh://localhost/tmp/new 100M
  Formatting 'ssh://localhost/tmp/new', fmt=raw size=104857600
  filename ssh://localhost/tmp/new: has_zero_init = 1
  $ sudo lvcreate -L 1G -n tmp /dev/fedora
    Logical volume "tmp" created
  $ ./qemu-img create ssh://localhost/dev/fedora/tmp 1G
  Formatting 'ssh://localhost/dev/fedora/tmp', fmt=raw size=1073741824
  filename ssh://localhost/dev/fedora/tmp: has_zero_init = 0

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:27 +02:00