Commit Graph

290 Commits

Author SHA1 Message Date
Kevin Wolf
9b036055ef qcow2: Remove old image creation function
They have been #ifdef'd out by the previous patch.

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

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

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

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

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

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

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

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

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

See docs/blkverify.txt for more information.

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

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

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

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

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

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

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

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

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

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

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

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

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

Signed-off-by: Kevin Wolf <mail@kevin-wolf.de>
2010-09-21 15:39:42 +02:00
Blue Swirl
95ee3914bf blkdebug: fix enum comparison
The signedness of enum types depend on the compiler implementation.
Therefore the check for negative values may or may not be meaningful.

Fix by explicitly casting to a signed integer.

Since the values are also checked earlier against event_names
table, this is an internal error. Change the 'if' to 'assert'.

This also avoids a warning with GCC flag -Wtype-limits.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-09-18 05:53:15 +00:00
Anthony Liguori
8b33d9eeba Revert "Make default invocation of block drivers safer (v3)"
This reverts commit 79368c81bf.

Conflicts:

	block.c

I haven't been able to come up with a solution yet for the corruption caused by
unaligned requests from the IDE disk so revert until a solution can be written.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-09-08 17:09:15 -05:00
Kevin Wolf
7ec5e6a4ca qcow2: Remove unnecessary flush after L2 write
When a new cluster was allocated, we only need a flush after the write to the
L2 table if it was a COW and we need to decrease the refcounts of the old
clusters.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-08 12:39:24 +02:00
Bernhard Kohl
05acda4d16 raw-posix: improve detection of scsi-generic devices
Allow symbolic links which point to /dev/sgX devices.

Signed-off-by: Bernhard Kohl <bernhard.kohl@nsn.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-08 12:39:19 +02:00
Kevin Wolf
897804d629 raw-posix: Don't use file name for host_cdrom detection on Linux
On Linux, we have code to detect CD-ROMs using an ioctl. We shouldn't lose
anything but false positives by removing the check for a /dev/cd* path.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-09-08 12:39:16 +02:00
Laurent Vivier
1d45f8b542 nbd: Introduce NBD named exports.
This patch allows to connect Qemu using NBD protocol to an nbd-server
using named exports.

For instance, if on the host "isoserver", in /etc/nbd-server/config, you have:

[generic]
[debian-500-ppc-netinst]
        exportname = /ISO/debian-500-powerpc-netinst.iso
[Fedora-10-ppc-netinst]
        exportname = /ISO/Fedora-10-ppc-netinst.iso

You can connect to it, using:

    qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst
    qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst

NOTE: you need at least nbd-server 2.9.18

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-08-30 18:29:22 +02:00
Loïc Minier
2aa326be0d vvfat: fat_chksum(): fix access above array bounds
Signed-off-by: Loïc Minier <loic.minier@linaro.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-08-30 18:29:22 +02:00
Izumi Tsutsui
010cb2b314 sheepdog: remove unnecessary includes
"qemu_socket.h" includes all necessary files and
including <netinet/tcp.h> without <netinet/in.h>
could cause errors on some systems.

Signed-off-by: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-08-30 18:29:22 +02:00
Kevin Wolf
336c1c1255 block: Fix bdrv_has_zero_init
Assuming that any image on a block device is not properly zero-initialized is
actually wrong: Only raw images have this problem. Any other image format
shouldn't care about it, they initialize everything properly themselves.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-08-03 15:57:22 +02:00
Stefan Weil
2ee9fb4801 block: Replace u_int8_t, u_int16_t, u_int32_t, u_int64_t by standard int types
There is no need to have a second set of integral types.
Replace them by the standard types from stdint.h.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
2010-07-25 16:59:38 +02:00
Anthony Liguori
79368c81bf Make default invocation of block drivers safer (v3)
CVE-2008-2004 described a vulnerability in QEMU whereas a malicious user could
trick the block probing code into accessing arbitrary files in a guest.  To
mitigate this, we added an explicit format parameter to -drive which disabling
block probing.

Fast forward to today, and the vast majority of users do not use this parameter.
libvirt does not use this by default nor does virt-manager.

Most users want block probing so we should try to make it safer.

This patch adds some logic to the raw device which attempts to detect a write
operation to the beginning of a raw device.  If the first 4 bytes happen to
match an image file that has a backing file that we support, it scrubs the
signature to all zeros.  If a user specifies an explicit format parameter, this
behavior is disabled.

I contend that while a legitimate guest could write such a signature to the
header, we would behave incorrectly anyway upon the next invocation of QEMU.
This simply changes the incorrect behavior to not involve a security
vulnerability.

I've tested this pretty extensively both in the positive and negative case.  I'm
not 100% confident in the block layer's ability to deal with zero sized writes
particularly with respect to the aio functions so some additional eyes would be
appreciated.

Even in the case of a single sector write, we have to make sure to invoked the
completion from a bottom half so just removing the zero sized write is not an
option.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-07-15 08:17:06 -05:00
MORITA Kazutaka
6defcc3784 sheepdog: fix compile error on systems without TCP_CORK
WIN32 is not only the system which doesn't have TCP_CORK (e.g. OS X).

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-07-07 20:54:56 +03:00
MORITA Kazutaka
33b1db1c88 block: add sheepdog driver for distributed storage support
Sheepdog is a distributed storage system for QEMU. It provides highly
available block level storage volumes to VMs like Amazon EBS.  This
patch adds a qemu block driver for Sheepdog.

Sheepdog features are:
- No node in the cluster is special (no metadata node, no control
  node, etc)
- Linear scalability in performance and capacity
- No single point of failure
- Autonomous management (zero configuration)
- Useful volume management support such as snapshot and cloning
- Thin provisioning
- Autonomous load balancing

The more details are available at the project site:
    http://www.osrg.net/sheepdog/

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-06 17:05:50 +02:00
Markus Armbruster
65d21bc73b raw-posix: Fix test for host CD-ROM
raw_pread_aligned() retries up to two times if the block device backs
a virtual CD-ROM (a drive with media=cdrom and if=ide, scsi, xen or
none).  This makes no sense.  Whether retrying reads can correct read
errors can only depend on what we're reading, not on how the result
gets used.  We need to check what whether we're reading from a
physical CD-ROM or floppy here.

I doubt retrying is useful even then.  Left for another day.

Impact:

* Virtual CD-ROM backed by host_cdrom behaves the same.

* Virtual CD-ROM backed by file or host_device no longer retries.

* A drive backed by host_cdrom now retries even if it's not a virtual
  CD-ROM.

* Any drive backed by host_floppy now retries.

While there, clean up gratuitous use of goto.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-06 17:05:49 +02:00
Kevin Wolf
9ac228e02c qcow2/vdi: Change check to distinguish error cases
This distinguishes between harmless leaks and real corruption. Hopefully users
better understand what qemu-img check wants to tell them.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-06 17:05:49 +02:00
Kevin Wolf
8db520cee8 blkdebug: Initialize state as 1
state = 0 in rules means that the rule is valid for any state. Therefore it's
impossible to have a rule that works only in the initial state. This changes
the initial state from 0 to 1 to make this possible.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-02 13:18:02 +02:00
Kevin Wolf
698f0d52cd blkdebug: Free QemuOpts after having read the config
Forgetting to free them means that the next instance inherits all rules and
gets its own rules only additionally.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-02 13:18:02 +02:00
Kevin Wolf
327cdad416 blkdebug: Fix set_state_opts definition
The list head was initialized to point to the wrong list, so all actions ended
up being handled as inject-error even if they were set-state in fact.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-02 13:18:02 +02:00
Kevin Wolf
19dbcbf7cc qcow2: Fix error handling during metadata preallocation
People were wondering why qemu-img check failed after they tried to preallocate
a large qcow2 file and ran out of disk space.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-07-02 13:18:01 +02:00
Kevin Wolf
f74550fd53 qcow2: Don't try to check tables that couldn't be loaded
Trying to check them leads to a second error message which is more confusing
than helpful:

    Can't get refcount for cluster 0: Invalid argument
    ERROR cluster 0 refcount=-22 reference=1

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
6882c8fa78 qcow2: Fix qemu-img check segfault on corrupted images
With corrupted images, we can easily get an cluster index that exceeds the
array size of the temporary refcount table.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
078a458e07 vpc: Use bdrv_(p)write_sync for metadata writes
Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
b8852e87d9 vmdk: Use bdrv_(p)write_sync for metadata writes
Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
8b3b720620 qcow2: Use bdrv_(p)write_sync for metadata writes
Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
5e5557d970 qcow: Use bdrv_(p)write_sync for metadata writes
Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Kevin Wolf
b0ad5a455d cow: Use bdrv_(p)write_sync for metadata writes
Use bdrv_(p)write_sync to ensure metadata integrity in case of a crash.
While at it, correct the wrong usage of errno.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-22 14:38:02 +02:00
Christoph Hellwig
2063392ae5 cow: use qemu block API
Use bdrv_pwrite to access the backing device instead of pread, and
convert the driver to implementing the bdrv_open method which gives
it an already opened BlockDriverState for the underlying device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:59 +02:00
Christoph Hellwig
893a9cb47c cow: stop using mmap
We don't have an equivalent to mmap in the qemu block API, so read and
write the bitmap directly.  At least in the dumb implementation added
in this patch this is a lot less efficient, but it means cow can also
work on windows, and over nbd or curl.  And it fixes qemu-iotests testcase
012 which did not work properly due to issues with read-only mmap access.

In addition we can also get rid of the now unused get_mmap_addr function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:59 +02:00
Christoph Hellwig
122bb9e32d cow: use pread/pwrite
Use pread/pwrite instead of lseek + read/write in preparation of using the
qemu block API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:59 +02:00
Kevin Wolf
68dba0bf45 qcow2: Restore L1 entry on l2_allocate failure
If writing the L1 table to disk failed, we need to restore its old content in
memory to avoid inconsistencies.

Reported-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:58 +02:00
Kevin Wolf
e14e8ba5d0 qcow2: Return real error code in load_refcount_block
This fixes load_refcount_block which completely ignored the return value of
write_refcount_block and always returned -EIO for bdrv_pwrite failure.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:58 +02:00
Kevin Wolf
2eaa8f6338 qcow2: Allow alloc_clusters_noref to return errors
Currently it would consider blocks for which get_refcount fails used. However,
it's unlikely that get_refcount would succeed for the next cluster, so it's not
really helpful. Return an error instead.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:58 +02:00
Kevin Wolf
018faafdbd qcow2: Allow get_refcount to return errors
get_refcount might need to load a refcount block from disk, so errors may
happen. Return the error code instead of assuming a refcount of 1 and change
the callers to respect error return values.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:58 +02:00
Kevin Wolf
6c6ea921ff vpc: Read/write multiple sectors at once
This changes the vpc block driver (for VHD) to read/write multiple sectors at
once instead of doing a request for each single sector.

Before this, running qemu-iotests for VPC took ages, now it's actually quite
reasonable to run it always (down from ~1 hour to 40 seconds for me).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-15 09:41:58 +02:00
Anthony Liguori
a4673e2762 Merge remote branch 'kwolf/for-anthony' into staging
Conflicts:
	hw/pc.c
2010-06-14 10:33:36 -05:00
Paul Brook
11165820d1 Move stdbool.h
Move inclusion of stdbool.h to common header files, instead of including
in an ad-hoc manner.

Signed-off-by: Paul Brook <paul@codesourcery.com>
2010-06-13 19:00:50 +01:00
Jes Sorensen
9040385dcc Cleanup: raw-posix.c: Be more consistent using BDRV_SECTOR_SIZE instead of 512
Clean up raw-posix.c to be more consistent using BDRV_SECTOR_SIZE
instead of hard coded 512 values.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-06-04 11:43:39 +02:00
Kevin Wolf
86fa8da837 qcow2: Fix corruption after error in update_refcount
After it is done with updating refcounts in the cache, update_refcount writes
all changed entries to disk. If a refcount block allocation fails, however,
there was no change yet and therefore first_index = last_index = -1. Don't
treat -1 as a normal sector index (resulting in a 512 byte write!) but return
without updating anything in this case.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:29:16 +02:00
Kevin Wolf
25408c0950 qcow2: Fix corruption after refblock allocation
Refblock allocation code needs to take into consideration that update_refcount
will load a different refcount block into the cache, so it must initialize the
cache for a new refcount block only afterwards. Not doing this means that not
only the refcount in the wrong block is updated, but also that the caller will
work on the wrong block.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:29:15 +02:00
Kevin Wolf
ed0df867d9 qcow2: Return right error code in write_refcount_block_entries
write_refcount_block_entries used to return -EIO for any errors. Change this to
return the real error code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:29:13 +02:00
Kevin Wolf
55c17e9821 qcow2: Change l2_load to return 0/-errno
Provide the error code to the caller instead of just indicating success/error.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:29:12 +02:00
Kevin Wolf
1c46efaa0a qcow2: Allow qcow2_get_cluster_offset to return errors
qcow2_get_cluster_offset() looks up a given virtual disk offset and returns the
offset of the corresponding cluster in the image file. Errors (e.g. L2 table
can't be read) are currenctly indicated by a return value of 0, which is
unfortuately the same as for any unallocated cluster. So in effect we can't
check for errors.

This makes the old return value a by-reference parameter and returns the usual
0/-errno error code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:29:11 +02:00
Kevin Wolf
175e11526e qcow2: Fix error handling in l2_allocate
l2_allocate has some intermediate states in which the image is inconsistent.
Change the order to write to the L1 table only after the new L2 table has
successfully been initialized.

Also reset the L2 cache in failure case, it's very likely wrong.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:14:25 +02:00
Kevin Wolf
1b7c801b40 qcow2: Clear L2 table cache after write error
If the L2 table was already updated in cache, but writing it to disk has
failed, we must not continue using the changed version in the cache to stay
consistent with what's on the disk.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-28 13:14:25 +02:00
Anthony Liguori
9c678ccd15 Merge remote branch 'kwolf/for-anthony' into staging 2010-05-24 10:53:41 -05:00
Blue Swirl
0bfcd599e3 Fix %lld or %llx printf format use
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-05-22 08:02:12 +00:00
Kevin Wolf
3e89cb0419 vvfat: More build fixes with DEBUG
Casting a pointer to an int doesn't work on 64 bit platforms. Use the %p printf
conversion specifier instead.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-21 11:49:19 +02:00
Riccardo Magliocchetti
792b45b142 vvfat: Fix compilation with DEBUG defined
gcc does not like passing a NULL where an int value is expected:

block/vvfat.c: In function ‘checkpoint’:
block/vvfat.c:2868: error: passing argument 2 of ‘remove_mapping’ makes
  integer from pointer without a cast

Signed-off-by: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-21 11:49:19 +02:00
Stefan Weil
f21dc3a465 block/vdi: Fix image opening and creation for odd disk sizes
The fix is based on a patch from Kevin Wolf. Here his comment:

"The number of blocks needs to be rounded up to cover all of the virtual hard
disk. Without this fix, we can't even open our own images if their size is not
a multiple of the block size."

While Kevin's patch addressed vdi_create, my modification also fixes
vdi_open which now accepts images with odd disk sizes.

v3:
Don't allow reading of disk images with too large disk sizes.
Neither VBoxManage nor old versions of qemu-img read such images.
This change requires rounding of odd disk sizes before we do the checks.

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: François Revol <revol@free.fr>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
64a31d5c3d dmg: use qemu block API
Use bdrv_pwrite to access the backing device instead of pread, and
convert the driver to implementing the bdrv_open method which gives
it an already opened BlockDriverState for the underlying device.

Dmg actually does an lseek to a negative offset in the open routine,
which we replace with offset arithmetics after doing a bdrv_getlength.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
16cdf7ce1a dmg: use pread
Use pread instead of lseek + read in preparation of using the qemu
block API.  Note that dmg actually uses the implicit file offset
a lot in dmg_open, and we had to replace it with an offset variable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
cd02a24b61 dmg: fix reading of uncompressed chunks
When dmg_read_chunk encounters an uncompressed chunk it currently
calls read without any previous adjustment of the file postion.

This seems very wrong, and the "reference" implementation in
dmg2img does a search to the same offset as done in the various
compression cases, so do the same here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Stefan Weil
dede4188cc block/vpc: Fix conversion from size to disk geometry
The VHD algorithm calculates a disk geometry
which is usually smaller than the requested size.

QEMU tried to round up but failed for certain sizes:

qemu-img create -f vpc disk.vpc 9437184
would create an image with 9435136 bytes
(which is too small for qemu-img convert).

Instead of hacking the geometry algorithm, the patch
increases the number of sectors until we get enough
sectors.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
1dec5a7097 parallels: use qemu block API
Use bdrv_pwrite to access the backing device instead of pread, and
convert the driver to implementing the bdrv_open method which gives
it an already opened BlockDriverState for the underlying device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
9d8b88f68c parallels: use pread
Use pread instead of lseek + read in preparation of using the qemu
block API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Stefan Weil
b76b6e95b8 block/vdi: Allow disk images of size 0
Even it is not very useful, users may create images of size 0.

Without the special option CONFIG_ZERO_MALLOC, qemu_mallocz
aborts execution when it is told to allocate 0 bytes,
so avoid this kind of call.

Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Kevin Wolf
b666d23950 block: Avoid unchecked casts for AIOCBs
Use container_of for one direction and &acb->common for the other one.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
7a6f391376 bochs: use qemu block API
Use bdrv_pwrite to access the backing device instead of pread, and
convert the driver to implementing the bdrv_open method which gives
it an already opened BlockDriverState for the underlying device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:05 +02:00
Christoph Hellwig
efbca10f10 bochs: use pread
Use pread instead of lseek + read in preparation of using the qemu
block API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:04 +02:00
Christoph Hellwig
20be49e47e cloop: use qemu block API
Use bdrv_pwrite to access the backing device instead of pread, and
convert the driver to implementing the bdrv_open method which gives
it an already opened BlockDriverState for the underlying device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:04 +02:00
Christoph Hellwig
c94304be3f cloop: use pread
Use pread instead of lseek + read in preparation of using the qemu
block API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-17 10:20:04 +02:00
Kevin Wolf
92b30744d7 qcow2: Remove static forward declaration
OpenBSDs gcc is said to generate warnings for this declaration, so don't
reference bdrv_qcow2 directly, but look it up using bdrv_find_format.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-05-07 17:11:37 +00:00
Kevin Wolf
de5f3f40af Revert "Fix OpenBSD build"
This reverts commit 20d97356c9.
The BlockDriver definition should stay at the end of source files.

Conflicts:

	block/qcow2.c

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-05-07 17:11:02 +00:00
Stefan Hajnoczi
419b19d9b4 qcow2: Implement bdrv_truncate() for growing images
This patch adds the ability to grow qcow2 images in-place using
bdrv_truncate().  This enables qemu-img resize command support for
qcow2.

Snapshots are not supported and bdrv_truncate() will return -ENOTSUP.
The notion of resizing an image with snapshots could lead to confusion:
users may expect snapshots to remain unchanged, but this is not possible
with the current qcow2 on-disk format where the header.size field is
global instead of per-snapshot.  Others may expect snapshots to change
size along with the current image data.  I think it is safest to not
support snapshots and perhaps add behavior later if there is a
consensus.

Backing images continue to work.  If the image is now larger than its
backing image, zeroes are read when accessing beyond the end of the
backing image.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:32 +02:00
Kevin Wolf
003fad6e2c qcow2: Remove abort on free_clusters failure
While it's true that during regular operation free_clusters failure would be a
bug, an I/O error can always happen. There's no need to kill the VM, the worst
thing that can happen (and it will) is that we leak some clusters.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:32 +02:00
Stefan Hajnoczi
4899d10d14 raw-posix: Use pread/pwrite instead of lseek+read/write
This patch combines the lseek+read/write calls to use pread/pwrite
instead.  This will result in fewer system calls and is already used by
AIO.

Thanks to Jan Kiszka <jan.kiszka@siemens.com> for identifying excessive
lseek and Christoph Hellwig <hch@lst.de> for confirming that this
approach should work.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:31 +02:00
Stefan Hajnoczi
508e089368 qcow2: Avoid shadowing variable in alloc_clusters_noref()
The i loop iterator is shadowed by the next free cluster index.  Both
using the variable name 'i' makes the code harder to read.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:31 +02:00
Kevin Wolf
6511ef7737 vmdk: Convert to bdrv_open
It's a format driver, so implement bdrv_open instead of bdrv_file_open.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:31 +02:00
Kevin Wolf
9949f97e84 vmdk: Clean up backing file handling
VMDK is doing interesting things when it needs to open a backing file. This
patch changes that part to look more like in other drivers. The nice side
effect is that the file name isn't needed any more in the open function.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:31 +02:00
Kevin Wolf
c336500df5 vmdk: Fix COW
When trying to do COW, VMDK wrote the data back to the backing file. This
problem was revealed by the patch that made backing files read-only. This patch
does not only fix the problem, but also simplifies the VMDK code a bit.

This fixes the backing file qemu-iotests cases for VMDK.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:31 +02:00
Kevin Wolf
66f82ceed6 block: Open the underlying image file in generic code
Format drivers shouldn't need to bother with things like file names, but rather
just get an open BlockDriverState for the underlying protocol. This patch
introduces this behaviour for bdrv_open implementation. For protocols which
need to access the filename to open their file/device/connection/... a new
callback bdrv_file_open is introduced which doesn't get an underlying file
opened.

For now, also some of the more obscure formats use bdrv_file_open because they
open() the file themselves instead of using the block.c functions. They need to
be fixed in later patches.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:30 +02:00
Christoph Hellwig
84a12e6648 block: separate raw images from the file protocol
We're running into various problems because the "raw" file access, which
is used internally by the various image formats is entangled with the
"raw" image format, which maps the VM view 1:1 to a file system.

This patch renames the raw file backends to the file protocol which
is treated like other protocols (e.g. nbd and http) and adds a new
"raw" image format which is just a wrapper around calls to the underlying
protocol.

The patch is surprisingly simple, besides changing the probing logical
in block.c to only look for image formats when using bdrv_open and
renaming of the old raw protocols to file there's almost nothing in there.

For creating images, a new bdrv_create_file is introduced which guesses the
protocol to use. This allows using qemu-img create -f raw (or just using the
default) for both files and host devices. Converting the other format drivers
to use this function to create their images is left for later patches.

The only issues still open are in the handling of the host devices.
Firstly in current qemu we can specifiy the host* format names
on various command line acceping images, but the new code can't
do that without adding some translation.  Second the layering breaks
the no_zero_init flag in the BlockDriver used by qemu-img.  I'm not
happy how this is done per-driver instead of per-state so I'll
prepare a separate patch to clean this up.

There's some more cleanup opportunity after this patch, e.g. using
separate lists and registration functions for image formats vs
protocols and maybe even host drivers, but this can be done at a
later stage.

Also there's a check for protocol in bdrv_open for the BDRV_O_SNAPSHOT
case that I don't quite understand, but which I fear won't work as
expected - possibly even before this patch.

Note that this patch requires various recent block patches from Kevin
and me, which should all be in his block queue.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-05-03 10:07:30 +02:00
Blue Swirl
88bf79500b Fix dead initialization, spotted by clang analyzer
Fix clang warnings:
/src/qemu/block/vvfat.c:1102:9: warning: Value stored to 'index3' during its initialization is never read
    int index3=index1+1;
/src/qemu/cmd.c:290:15: warning: Value stored to 'p' during its initialization is never read
        char *p = result;

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-04-25 15:27:14 +00:00
Blue Swirl
20d97356c9 Fix OpenBSD build
GCC 3.3.5 generates warnings for static forward declarations of data, so
rearrange code to use static forward declarations of functions instead.

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2010-04-23 20:19:47 +00:00
Stefan Hajnoczi
d4c146f0da qcow2: Use QLIST_FOREACH_SAFE macro
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:21:58 +02:00
Kevin Wolf
c46e116723 qcow2: Return 0/-errno in l2_allocate
Returning NULL on error doesn't allow distinguishing between different errors.
Change the interface to return an integer for -errno.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Kevin Wolf
f7defcb627 qcow2: Return 0/-errno in write_l1_entry
Change write_l1_entry to return the real error code instead of -1.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Kevin Wolf
c835d00fc8 qcow2: Fix error return code in qcow2_alloc_cluster_link_l2
Fix qcow2_alloc_cluster_link_l2 to return the real error code like it does in
all other error cases.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Kevin Wolf
79a31189d4 qcow2: Return 0/-errno in write_l2_entries
Change write_l2_entries to return the real error code instead of -1.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Christoph Hellwig
50779cc264 block: split raw_getlength
Split up the raw_getlength into separate generic, solaris and BSD
versions to reduce the ifdef maze a bit.  The BSD variant still
is a complete maze, but to clean it up properly we'd need some
people using the BSD variants to figure out what code is used
for what variant.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Kevin Wolf
d6e9098e10 Replace calls of old bdrv_open
What is known today as bdrv_open2 becomes the new bdrv_open. All remaining
callers of the old function are converted to the new one. In some places they
even know the right format, so they should have used bdrv_open2 from the
beginning.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00
Kevin Wolf
4768fa902c qcow2: Fix creation of large images
qcow_create2 assumes that the new image will only need one cluster for its
refcount table initially. Obviously that's not true any more when the image is
big enough (exact value depends on the cluster size).

This patch calculates the refcount table size dynamically.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2010-04-23 16:08:46 +02:00