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438 Commits

Author SHA1 Message Date
Peter Maydell 6bd8ab6889 Block layer patches
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches

# gpg: Signature made Thu 19 May 2016 16:09:27 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream: (31 commits)
  qemu-iotests: Fix regression in 136 on aio_read invalid
  qemu-iotests: Simplify 109 with unaligned qemu-img compare
  qemu-io: Fix recent UI updates
  block: clarify error message for qmp-eject
  qemu-iotests: Some more write_zeroes tests
  qcow2: Fix write_zeroes with partially allocated backing file cluster
  qcow2: fix condition in is_zero_cluster
  block: Propagate AioContext change to all children
  block: Remove BlockDriverState.blk
  block: Don't return throttling info in query-named-block-nodes
  block: Avoid bs->blk in bdrv_next()
  block: Add bdrv_has_blk()
  block: Remove bdrv_aio_multiwrite()
  blockjob: Don't touch BDS iostatus
  blockjob: Don't set iostatus of target
  block: User BdrvChild callback for device name
  block: Use BdrvChild callbacks for change_media/resize
  block: Don't check throttled reqs in bdrv_requests_pending()
  Revert "block: Forbid I/O throttling on nodes with multiple parents for 2.6"
  block: Remove bdrv_move_feature_fields()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-05-19 16:54:12 +01:00
Kevin Wolf 5efdf53227 qcow2: Fix write_zeroes with partially allocated backing file cluster
In order to correctly check whether a given cluster is read as zero, we
don't only need to check whether bdrv_get_block_status_above() sets
BDRV_BLOCK_ZERO, but also if all sectors for the whole cluster have the
same status.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
2016-05-19 16:45:31 +02:00
Denis V. Lunev f575f145f4 qcow2: fix condition in is_zero_cluster
We should check for (res & BDRV_BLOCK_ZERO) only. The situation when we
will have !(res & BDRV_BLOCK_DATA) and will not have BDRV_BLOCK_ZERO is
not possible for images with bdi.unallocated_blocks_are_zero == true.

For those images where it's false, however, it can happen and we must
not consider the data zeroed then or we would corrupt the image.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-19 16:45:31 +02:00
Paolo Bonzini 58369e22cf qemu-common: stop including qemu/bswap.h from qemu-common.h
Move it to the actual users.  There are still a few includes of
qemu/bswap.h in headers; removing them is left for future work.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-19 16:42:28 +02:00
Fam Zheng c9e9e9c66c block: Drop superfluous invalidating bs->file from drivers
Now they are invalidated by the block layer, so it's not necessary to
do this in block drivers' implementations of .bdrv_invalidate_cache.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Denis V. Lunev 2928abce6d qcow2: improve qcow2_co_write_zeroes()
There is a possibility that qcow2_co_write_zeroes() will be called
with the partial block. This could be synthetically triggered with
    qemu-io -c "write -z 32k 4k"
and can happen in the real life in qemu-nbd. The latter happens under
the following conditions:
    (1) qemu-nbd is started with --detect-zeroes=on and is connected to the
        kernel NBD client
    (2) third party program opens kernel NBD device with O_DIRECT
    (3) third party program performs write operation with memory buffer
        not aligned to the page
In this case qcow2_co_write_zeroes() is unable to perform the operation
and mark entire cluster as zeroed and returns ENOTSUP. Thus the caller
switches to non-optimized version and writes real zeroes to the disk.

The patch creates a shortcut. If the block is read as zeroes, f.e. if
it is unallocated, the request is extended to cover full block.
User-visible situation with this block is not changed. Before the patch
the block is filled in the image with real zeroes. After that patch the
block is marked as zeroed in metadata. Thus any subsequent changes in
backing store chain are not affected.

Kevin, thank you for a cool suggestion.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Eric Blake 8341f00dc2 block: Allow BDRV_REQ_FUA through blk_pwrite()
We have several block drivers that understand BDRV_REQ_FUA,
and emulate it in the block layer for the rest by a full flush.
But without a way to actually request BDRV_REQ_FUA during a
pass-through blk_pwrite(), FUA-aware block drivers like NBD are
forced to repeat the emulation logic of a full flush regardless
of whether the backend they are writing to could do it more
efficiently.

This patch just wires up a flags argument; followup patches
will actually make use of it in the NBD driver and in qemu-io.

Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:08 +02:00
Max Reitz 4e876bcf2b qcow2: Prevent backing file names longer than 1023
We reject backing file names with a length of more than 1023 characters
when opening a qcow2 file, so we should not produce such files
ourselves.

Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-04-12 18:06:51 +02:00
Kevin Wolf 72e775c7d9 block: Always set writeback mode in blk_new_open()
All callers of blk_new_open() either don't rely on the WCE bit set after
blk_new_open() because they explicitly set it anyway, or they pass
BDRV_O_CACHE_WB unconditionally.

This patch changes blk_new_open() so that it always enables writeback
mode and asserts that BDRV_O_CACHE_WB is clear. For those callers that
used to pass BDRV_O_CACHE_WB unconditionally, the flag is removed now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30 12:16:01 +02:00
Daniel P. Berrange e6ff69bf5e block: move encryption deprecation warning into qcow code
For a couple of releases we have been warning

  Encrypted images are deprecated
  Support for them will be removed in a future release.
  You can use 'qemu-img convert' to convert your image to an unencrypted one.

This warning was issued by system emulators, qemu-img, qemu-nbd
and qemu-io. Such a broad warning was issued because the original
intention was to rip out all the code for dealing with encryption
inside the QEMU block layer APIs.

The new block encryption framework used for the LUKS driver does
not rely on the unloved block layer API for encryption keys,
instead using the QOM 'secret' object type. It is thus no longer
appropriate to warn about encryption unconditionally.

When the qcow/qcow2 drivers are converted to use the new encryption
framework too, it will be practical to keep AES-CBC support present
for use in qemu-img, qemu-io & qemu-nbd to allow for interoperability
with older QEMU versions and liberation of data from existing encrypted
qcow2 files.

This change moves the warning out of the generic block code and
into the qcow/qcow2 drivers. Further, the warning is set to only
appear when running the system emulators, since qemu-img, qemu-io,
qemu-nbd are expected to support qcow2 encryption long term now that
the maint burden has been eliminated.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-30 12:12:15 +02:00
Veronia Bahaa f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Eric Blake 32bafa8fdd qapi: Don't special-case simple union wrappers
Simple unions were carrying a special case that hid their 'data'
QMP member from the resulting C struct, via the hack method
QAPISchemaObjectTypeVariant.simple_union_type().  But by using
the work we started by unboxing flat union and alternate
branches, coupled with the ability to visit the members of an
implicit type, we can now expose the simple union's implicit
type in qapi-types.h:

| struct q_obj_ImageInfoSpecificQCow2_wrapper {
|     ImageInfoSpecificQCow2 *data;
| };
|
| struct q_obj_ImageInfoSpecificVmdk_wrapper {
|     ImageInfoSpecificVmdk *data;
| };
...
| struct ImageInfoSpecific {
|     ImageInfoSpecificKind type;
|     union { /* union tag is @type */
|         void *data;
|-        ImageInfoSpecificQCow2 *qcow2;
|-        ImageInfoSpecificVmdk *vmdk;
|+        q_obj_ImageInfoSpecificQCow2_wrapper qcow2;
|+        q_obj_ImageInfoSpecificVmdk_wrapper vmdk;
|     } u;
| };

Doing this removes asymmetry between QAPI's QMP side and its
C side (both sides now expose 'data'), and means that the
treatment of a simple union as sugar for a flat union is now
equivalent in both languages (previously the two approaches used
a different layer of dereferencing, where the simple union could
be converted to a flat union with equivalent C layout but
different {} on the wire, or to an equivalent QMP wire form
but with different C representation).  Using the implicit type
also lets us get rid of the simple_union_type() hack.

Of course, now all clients of simple unions have to adjust from
using su->u.member to using su->u.member.data; while this touches
a number of files in the tree, some earlier cleanup patches
helped minimize the change to the initialization of a temporary
variable rather than every single member access.  The generated
qapi-visit.c code is also affected by the layout change:

|@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member
|     }
|     switch (obj->type) {
|     case IMAGE_INFO_SPECIFIC_KIND_QCOW2:
|-        visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err);
|+        visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err);
|         break;
|     case IMAGE_INFO_SPECIFIC_KIND_VMDK:
|-        visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err);
|+        visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err);
|         break;
|     default:
|         abort();

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-18 10:29:26 +01:00
Max Reitz efaa7c4eeb blockdev: Split monitor reference from BB creation
Before this patch, blk_new() automatically assigned a name to the new
BlockBackend and considered it referenced by the monitor. This patch
removes the implicit monitor_add_blk() call from blk_new() (and
consequently the monitor_remove_blk() call from blk_delete(), too) and
thus blk_new() (and related functions) no longer take a BB name
argument.

In fact, there is only a single point where blk_new()/blk_new_open() is
called and the new BB is monitor-owned, and that is in blockdev_init().
Besides thus relieving us from having to invent names for all of the BBs
we use in qemu-img, this fixes a bug where qemu cannot create a new
image if there already is a monitor-owned BB named "image".

If a BB and its BDS tree are created in a single operation, as of this
patch the BDS tree will be created before the BB is given a name
(whereas it was the other way around before). This results in minor
change to the output of iotest 087, whose reference output is amended
accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-17 15:47:56 +01:00
Max Reitz a55448b368 qapi: Drop QERR_UNKNOWN_BLOCK_FORMAT_FEATURE
Just specifying a custom string is simpler in basically all places that
used it, and in addition, specifying the BB or node name is something we
generally do not do in other error messages when opening a BDS, so we
should not do it here.

This changes the output for iotest 036 (to the better, in my opinion),
so the reference output needs to be changed accordingly.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-17 15:47:56 +01:00
Kevin Wolf 23588797b6 qcow2: Use BB functions in .bdrv_create()
All users of the block layers are supposed to go through a BlockBackend.
The .bdrv_create() implementation is one such user, so this patch
converts it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Kevin Wolf 6340472c54 block: Use writeback in .bdrv_create() implementations
There's no reason to use a writethrough cache mode while creating an
image.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Fam Zheng 178b4db7e5 qcow2: Assign bs->file->bs to file in qcow2_co_get_block_status
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-4-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02 17:50:47 +01:00
Fam Zheng 67a0fd2a9b block: Add "file" output parameter to block status query functions
The added parameter can be used to return the BDS pointer which the
valid offset is referring to. Its value should be ignored unless
BDRV_BLOCK_OFFSET_VALID in ret is set.

Until block drivers fill in the right value, let's clear it explicitly
right before calling .bdrv_get_block_status.

The "bs->file" condition in bdrv_co_get_block_status is kept now to keep iotest
case 102 passing, and will be fixed once all drivers return the right file
pointer.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-2-git-send-email-famz@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02 17:50:47 +01:00
Kevin Wolf 191fb11bdf qcow2: Make image inaccessible after failed qcow2_invalidate_cache()
If qcow2_invalidate_cache() fails, we are in a state where qcow2_close()
has already been completed, but the image hasn't been reopened yet.
Calling into any qcow2 function for an image in this state will cause
crashes.

The real solution would be to get rid of the close/open pair and instead
do an atomic reset of the involved data structures, but this isn't
trivial, so let's just make the image inaccessible for now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:24 +01:00
Kevin Wolf 140fd5a69c qcow2: Fix BDRV_O_INACTIVE handling in qcow2_invalidate_cache()
What qcow2_invalidate_cache() should do is close the image with
BDRV_O_INACTIVE set and reopen it with the flag cleared. In fact, it
used to do exactly the opposite: qcow2_close() relied on bs->open_flags,
which is already updated to have cleared BDRV_O_INACTIVE at this point,
whereas qcow2_open() was called with s->flags, which has the flag still
set. Fix this.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Kevin Wolf ec6d891224 qcow2: Implement .bdrv_inactivate
The callback has to ensure that closing or flushing the image afterwards
wouldn't cause a write access to the image files. This means that just
the caches have to be written out, which is part of the existing
.bdrv_close implementation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Kevin Wolf 04c01a5c8f block: Rename BDRV_O_INCOMING to BDRV_O_INACTIVE
Instead of covering only the state of images on the migration
destination before the migration is completed, the flag will also cover
the state of images on the migration source after completion. This
common state implies that the image is technically still open, but no
writes will happen and any cached contents will be reloaded from disk if
and when the image leaves this state.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Kevin Wolf b527c9b392 qcow2: Write full header on image creation
When creating a qcow2 image, we didn't necessarily call
qcow2_update_header(), but could end up with the basic header that
qcow2_create2() created manually. One thing that this basic header
lacks is the feature table. Let's make sure that it's always present.

This requires a few updates to test cases as well.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Kevin Wolf 1a4828c793 qcow2: Write feature table only for v3 images
Version 2 images don't have feature bits, so writing a feature table to
those images is kind of pointless.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-20 13:36:23 +01:00
Peter Maydell 80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Markus Armbruster e43bfd9c87 error: Use error_prepend() where it makes obvious sense
Done with this Coccinelle semantic patch

    @@
    expression FMT, E1, E2;
    expression list ARGS;
    @@
    -    error_setg(E1, FMT, ARGS, error_get_pretty(E2));
    +    error_propagate(E1, E2);/*###*/
    +    error_prepend(E1, FMT/*@@@*/, ARGS);

followed by manual cleanup, first because I can't figure out how to
make Coccinelle transform strings, and second to get rid of now
superfluous error_propagate().

We now use or propagate the original error whole instead of just its
message obtained with error_get_pretty().  This avoids suppressing its
hint (see commit 50b7b00), but I can't see how the errors touched in
this commit could come with hints.  It also improves the message
printed with &error_abort when we screw up (see commit 1e9b65b).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-01-13 15:16:17 +01:00
Denis V. Lunev b1fc8f934b qcow2: insert assert into qcow2_get_specific_info()
s->qcow_version is always set to 2 or 3. Let's assert if this is wrong.

Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz 61ce55fc02 qcow2: Invoke refcount order amendment function
Make use of qcow2_change_refcount_order() to support changing the
refcount order with qemu-img amend.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz c293a80927 qcow2: Use intermediate helper CB for amend
If there is more than one time-consuming operation to be performed for
qcow2_amend_options(), we need an intermediate CB which coordinates the
progress of the individual operations and passes the result to the
original status callback.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz 1038bbb803 qcow2: Split upgrade/downgrade paths for amend
If the image version should be upgraded, that is the first we should do;
if it should be downgraded, that is the last we should do. So split the
version change block into an upgrade part at the start and a downgrade
part at the end.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz 164e0f89cc qcow2: Use abort() instead of assert(false)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz 29d72431ef qcow2: Use error_report() in qcow2_amend_options()
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Max Reitz 8b13976d3f block: Add opaque value to the amend CB
Add an opaque value which is to be passed to the bdrv_amend_options()
status callback.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-12-18 14:34:43 +01:00
Kevin Wolf 5365f44dfa qcow2: Add .bdrv_join_options callback
qcow2 accepts a few driver-specific options that overlap semantically
(e.g. "overlap-check" is an alias of "overlap-check.template", and any
missing cache size option is derived from the given ones).

When bdrv_reopen() merges the set of updated options with left out
options that should be kept at their old value, we need to consider this
and filter out any duplicates (which would generally cause errors
because new and old value would contradict each other).

This patch adds a .bdrv_join_options callback to BlockDriver and
implements it for qcow2.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2015-12-18 14:34:42 +01:00
Eric Blake 7fb1cf1606 qapi: Don't let implicit enum MAX member collide
Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes.  Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.

This patch was mostly generated by applying a temporary patch:

|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
|     max_index = c_enum_const(name, 'MAX', prefix)
|     ret += mcgen('''
|     [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
|                max_index=max_index)

then running:

$ cat qapi-{types,event}.c tests/test-qapi-types.c |
    sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list

The only things not generated are the changes in scripts/qapi.py.

Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-12-17 08:21:28 +01:00
Eric Blake 6a8f9661dc block: Convert to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

Make the conversion to the new layout for block-related code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-16-git-send-email-eblake@redhat.com>
[Commit message tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-11-02 08:30:27 +01:00
Kevin Wolf 760e006384 block: Convert bs->backing_hd to BdrvChild
This is the final step in converting all of the BlockDriverState
pointers that block drivers use to BdrvChild.

After this patch, bs->children contains the full list of child nodes
that are referenced by a given BDS, and these children are only
referenced through BdrvChild, so that updating the pointer in there is
enough for changing edges in the graph.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Kevin Wolf 9a4f4c3156 block: Convert bs->file to BdrvChild
This patch removes the temporary duplication between bs->file and
bs->file_child by converting everything to BdrvChild.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Kevin Wolf 5b0959a7d4 qcow2: Support updating driver-specific options in reopen
For updating the cache sizes, disabling lazy refcounts and updating the
clean_cache_timer there is a bit more to do than just changing the
variables, but otherwise we're all set for changing options during
bdrv_reopen().

Just implement the missing pieces and hook the functions up in
bdrv_reopen().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:37 +02:00
Kevin Wolf ee55b17304 qcow2: Make qcow2_update_options() suitable for transactions
Before we can allow updating options at runtime with bdrv_reopen(), we
need to split the function into prepare/commit/abort parts.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:37 +02:00
Kevin Wolf c1344ded70 qcow2: Fix memory leak in qcow2_update_options() error path
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf 007dbc396c qcow2: Leave s unchanged on qcow2_update_options() failure
On return, either all new options should be applied to BDRVQcowState (on
success), or all of the old settings should be preserved (on failure).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf 94edf3fbe8 qcow2: Move rest of option handling to qcow2_update_options()
With this commit, the handling of driver-specific options in
qcow2_open() is completely separated out into qcow2_update_options().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf 90efa0eaef qcow2: Move qcow2_update_options() call up
qcow2_update_options() only updates some variables in BDRVQcowState and
doesn't really depend on other parts of it being initialised yet, so it
can be moved so that it immediately follows the other half of option
handling code in qcow2_open().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf 4c75d1a157 qcow2: Factor out qcow2_update_options()
Eventually we want to be able to change options at runtime. As a first
step towards that goal, separate some option handling code from the
general initialisation code in qcow2_open().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf f113ae839e qcow2: Improve error message
Eric says that "any" sounds better than "either", and my non-native
feeling says the same, so let's change it.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-09-14 16:51:36 +02:00
Kevin Wolf ff99129ab8 qcow2: Rename BDRVQcowState to BDRVQcow2State
BDRVQcowState is already used by qcow1, and gdb is always confused which
one to use. Rename the qcow2 one so they can be distinguished.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2015-09-14 16:51:36 +02:00
Max Reitz 6ebf9aa2ef block: Drop drv parameter from bdrv_open()
Now that this parameter is effectively unused, we can drop it and just
pass NULL on to bdrv_open_inherit().

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-09-14 16:51:36 +02:00
Max Reitz e6641719fe block: Always pass NULL as drv for bdrv_open()
Change all callers of bdrv_open() to pass the driver name in the options
QDict instead of passing its BlockDriver pointer.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-09-14 16:51:36 +02:00
Alberto Garcia 279621c046 qcow2: add option to clean unused cache entries after some time
This adds a new 'cache-clean-interval' option that cleans all qcow2
cache entries that haven't been used in a certain interval, given in
seconds.

This allows setting a large L2 cache size so it can handle scenarios
with lots of I/O and at the same time use little memory during periods
of inactivity.

This feature currently relies on MADV_DONTNEED to free that memory, so
it is not useful in systems that don't follow that behavior.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a70d12da60433df9360ada648b3f34b8f6f354ce.1438690126.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-09-04 21:00:32 +02:00
Daniel P. Berrange f6fa64f6d2 block: convert qcow/qcow2 to use generic cipher API
Switch the qcow/qcow2 block driver over to use the generic cipher
API, this allows it to use the pluggable AES implementations,
instead of being hardcoded to use QEMU's built-in impl.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-10-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-08 13:11:01 +02:00
Daniel P. Berrange 6f2945cde6 crypto: move built-in AES implementation into crypto/
To prepare for a generic internal cipher API, move the
built-in AES implementation into the crypto/ directory

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-3-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-07 12:04:13 +02:00
Markus Armbruster c6bd8c706a qerror: Clean up QERR_ macros to expand into a single string
These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
  delete it from the QERR_ macro.  No change after preprocessing.

* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
  error_setg(...).  Again, no change after preprocessing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
Max Reitz bc85ef265a qcow2: Add DEFAULT_L2_CACHE_CLUSTERS
If a relatively large cluster size is chosen, the default of 1 MB L2
cache is not really appropriate. In this case, unless overridden by the
user, the default cache size should not be determined by its size in
bytes but by the number of L2 tables (clusters) it is supposed to
contain.

Note that without this patch, MIN_L2_CACHE_SIZE will effectively take
over the same role. However, providing space for just two L2 tables is
not enough to be the default.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-06-12 15:54:01 +02:00
Daniel P. Berrange 8336aafae1 qcow2/qcow: protect against uninitialized encryption key
When a qcow[2] file is opened, if the header reports an
encryption method, this is used to set the 'crypt_method_header'
field on the BDRVQcow[2]State struct, and the 'encrypted' flag
in the BDRVState struct.

When doing I/O operations, the 'crypt_method' field on the
BDRVQcow[2]State struct is checked to determine if encryption
needs to be applied.

The crypt_method_header value is copied into crypt_method when
the bdrv_set_key() method is called.

The QEMU code which opens a block device is expected to always
do a check

   if (bdrv_is_encrypted(bs)) {
       bdrv_set_key(bs, ....key...);
   }

If code forgets to do this, then 'crypt_method' is never set
and so when I/O is performed, QEMU writes plain text data
into a sector which is expected to contain cipher text, or
when reading, will return cipher text instead of plain
text.

Change the qcow[2] code to consult bs->encrypted when deciding
whether encryption is required, and assert(s->crypt_method)
to protect against cases where the caller forgets to set the
encryption key.

Also put an assert in the set_key methods to protect against
the case where the caller sets an encryption key on a block
device that does not have encryption

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-05-22 17:08:01 +02:00
Alberto Garcia dc881b441d block: add 'node-name' field to BLOCK_IMAGE_CORRUPTED
Since this event can occur in nodes that cannot have a device name
associated, include also a field with the node name.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 147cec5b3594f4bec0cb41c98afe5fcbfb67567c.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Alberto Garcia 81e5f78a9f block: use bdrv_get_device_or_node_name() in error messages
There are several error messages that identify a BlockDriverState by
its device name. However those errors can be produced in nodes that
don't have a device name associated.

In those cases we should use bdrv_get_device_or_node_name() to fall
back to the node name and produce a more meaningful message. The
messages are also updated to use the more generic term 'node' instead
of 'device'.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 9823a1f0514fdb0692e92868661c38a9e00a12d6.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Stefan Hajnoczi 786a4ea82e Convert (ffs(val) - 1) to ctz32(val)
This commit was generated mechanically by coccinelle from the following
semantic patch:

@@
expression val;
@@
- (ffs(val) - 1)
+ ctz32(val)

The call sites have been audited to ensure the ffs(0) - 1 == -1 case
never occurs (due to input validation, asserts, etc).  Therefore we
don't need to worry about the fact that ctz32(0) == 32.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427124571-28598-5-git-send-email-stefanha@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:08 +02:00
Kevin Wolf e4603fe139 qcow2: Fix header update with overridden backing file
In recent qemu versions, it is possible to override the backing file
name and format that is stored in the image file with values given at
runtime. In such cases, the temporary override could end up in the
image header if the qcow2 header was updated, while obviously correct
behaviour would be to leave the on-disk backing file path/format
unchanged.

Fix this and add a test case for it.

Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1428411796-2852-1-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-04-08 10:29:20 +01:00
Wen Congyang 87b86e7ef2 qcow2: fix the macro QCOW_MAX_L1_SIZE's use
QCOW_MAX_L1_SIZE's unit is byte, and l1_size's unit
is l1 table entry size(8 bytes).

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Message-id: 54FFB0F1.5010307@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-03-12 17:41:23 +00:00
Max Reitz 06d05fa738 qcow2: Allow creation with refcount order != 4
Add a creation option to qcow2 for setting the refcount order of images
to be created, and respect that option's value.

This breaks some test outputs, fix them.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:21 +01:00
Max Reitz 8a17b83cc3 qcow2: Use symbolic macros in qcow2_amend_options
qcow2_amend_options() should not compare options against some inline
strings but rather use the symbolic macros available for each of the
creation options.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:21 +01:00
Max Reitz bd4b167f84 qcow2: refcount_order parameter for qcow2_create2
Add a refcount_order parameter to qcow2_create2(), use that value for
the image header and for calculating the size required for
preallocation.

For now, always pass 4.

This addition requires changes to the calculation of the file size for
the "full" and "falloc" preallocation modes. That in turn is a nice
opportunity to add a comment about that calculation not necessarily
being exact (and that being intentional).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:21 +01:00
Max Reitz b72faf9f78 qcow2: Open images with refcount order != 4
No longer refuse to open images with a different refcount entry width
than 16 bits; only reject images with a refcount width larger than 64
bits (which is prohibited by the specification).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:21 +01:00
Max Reitz 0709c5a153 qcow2: Add refcount_bits to format-specific info
Add the bit width of every refcount entry to the format-specific
information.

In contrast to lazy_refcounts and the corrupt flag, this should be
always emitted, even for compat=0.10 although it does not support any
refcount width other than 16 bits. This is because if a boolean is
optional, one normally assumes it to be false when omitted; but if an
integer is not specified, it is rather difficult to guess its value.

This new field breaks some test outputs, fix them.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:20 +01:00
Max Reitz 346a53df38 qcow2: Add two new fields to BDRVQcowState
Add two new fields regarding refcount information (the bit width of
every entry and the maximum refcount value) to the BDRVQcowState.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-03-10 14:02:20 +01:00
Markus Armbruster f43e47dbf6 QemuOpts: Drop qemu_opt_set(), rename qemu_opt_set_err(), fix use
qemu_opt_set() is a wrapper around qemu_opt_set() that reports the
error with qerror_report_err().

Most of its users assume the function can't fail.  Make them use
qemu_opt_set_err() with &error_abort, so that should the assumption
ever break, it'll break noisily.

Just two users remain, in util/qemu-config.c.  Switch them to
qemu_opt_set_err() as well, then rename qemu_opt_set_err() to
qemu_opt_set().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-26 14:49:31 +01:00
Markus Armbruster 39101f2511 QemuOpts: Convert qemu_opt_set_number() to Error, fix its use
Return the Error object instead of reporting it with
qerror_report_err().

Change callers that assume the function can't fail to pass
&error_abort, so that should the assumption ever break, it'll break
noisily.

Turns out all callers outside its unit test assume that.  We could
drop the Error ** argument, but that would make the interface less
regular, so don't.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-26 14:47:32 +01:00
Max Reitz c0191e763b block: Remove "growable" from BDS
Now that request clamping is done in the BlockBackend, the "growable"
field can be removed from the BlockDriverState. All BDSs are now treated
as being "growable" (that is, they are allowed to grow; they are not
necessarily actually able to).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1423162705-32065-16-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-02-16 15:07:19 +00:00
Jeff Cody e729fa6afe block: fix off-by-one error in qcow and qcow2
This fixes an off-by-one error introduced in 9a29e18.  Both qcow and
qcow2 need to make sure to leave room for string terminator '\0' for
the backing file, so the max length of the non-terminated string is
either 1023 or PATH_MAX - 1.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-02-06 17:24:21 +01:00
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
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 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
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
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 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 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 5b84106bd9 qcow2: Fix leaks in dirty images
When opening dirty images, qcow2's repair function should not only
repair errors but leaks as well.

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>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-23 15:34:01 +02:00
Max Reitz 1d13d65466 qcow2: Calculate refcount block entry count
The size of a refblock entry is (in theory) variable; calculate
therefore the number of entries per refblock and the according bit shift
(1 << x == entry count) when opening an image.

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 15:34:01 +02:00
Markus Armbruster bfb197e0d9 block: Eliminate BlockDriverState member device_name[]
device_name[] can become non-empty only in bdrv_new_root() and
bdrv_move_feature_fields().  The latter is used only to undo damage
done by bdrv_swap().  The former is called only by blk_new_with_bs().
Therefore, when a BlockDriverState's device_name[] is non-empty, then
it's been created with a BlockBackend, and vice versa.  Furthermore,
blk_new_with_bs() keeps the two names equal.

Therefore, device_name[] is redundant.  Eliminate it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:26 +02:00
Max Reitz 9009b1963c qapi: Add corrupt field to ImageInfoSpecificQCow2
Just like lazy-refcounts, this field will be present iff the qcow2
compat level is 1.1 (or probably any future revision).

As expected, this breaks some tests due to the new field present in
qemu-img info output; so fix their output accordingly.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1412105489-7681-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-10-04 19:18:17 +01:00
Max Reitz ee42b5ce0b qcow2: Add overlap-check.template option
Being able to set the overlap-check option to a string and then refine
it via the overlap-check.* options is a nice idea for the command line
but does not work so well for non-flattened dicts. In that case, one can
only specify either but not both, so add a field to overlap-check.*
which does the same as directly specifying overlap-check but can be used
in conjunction with the other fields in non-flattened dicts.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1408557576-14574-4-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:34 +01:00
Max Reitz 7b17ce60cc qcow2: Fix leak of QemuOpts in qcow2_open()
Currently, the QemuOpts object opts is leaked if anything fails from its
creation up to and including the image repair block. Fix this by freeing
that object in the fail path.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1408557576-14574-2-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:32 +01:00
Max Reitz 85186ebdac qcow2: Add qcow2_signal_corruption()
Add a helper function for easily marking an image corrupt (on fatal
corruptions) while outputting an informative message to stderr and via
QAPI.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Message-id: 1409926039-29044-3-git-send-email-mreitz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:27 +01:00
Hu Tao 0e4271b711 qcow2: Add falloc and full preallocation option
preallocation=falloc allocates disk space by posix_fallocate(),
preallocation=full allocates disk space by writing zeros to disk.
Both modes imply preallocation=metadata.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Hu Tao ffeaac9b4e qapi: introduce PreallocMode and new PreallocModes full and falloc.
This patch prepares for the subsequent patches.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Hu Tao 180e95265e block: don't convert file size to sector size
and avoid converting it back later.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Hu Tao c2eb918e32 block: round up file size to nearest sector
Currently the file size requested by user is rounded down to nearest
sector, causing the actual file size could be a bit less than the size
user requested. Since some formats (like qcow2) record virtual disk
size in bytes, this can make the last few bytes cannot be accessed.

This patch fixes it by rounding up file size to nearest sector so that
the actual file size is no less than the requested file size.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-12 15:43:06 +02:00
Max Reitz 6c1c8d5d3e qcow2: Add runtime options for cache sizes
Add options for specifying the size of the metadata caches. This can
either be done directly for each cache (if only one is given, the other
will be derived according to a default ratio) or combined for both.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-20 11:51:28 +02:00
Max Reitz 440ba08aea qcow2: Constant cache size in bytes
Specifying the metadata cache sizes in clusters results in less clusters
(and much less bytes) covered for small cluster sizes and vice versa.
Using a constant byte size reduces this difference, and makes it
possible to manually specify the cache size in an easily comprehensible
unit.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-20 11:51:28 +02:00
Kevin Wolf de82815db1 qcow2: Handle failure for potentially large allocations
Some code in the block layer makes potentially huge allocations. Failure
is not completely unexpected there, so avoid aborting qemu and handle
out-of-memory situations gracefully.

This patch addresses the allocations in the qcow2 block driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-15 15:07:15 +02:00
Markus Armbruster 75d3d21f9e block: Drop superfluous aligning of bdrv_getlength()'s value
It returns a multiple of the sector size.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-15 15:07:13 +02:00
Markus Armbruster 57322b7811 block: Use bdrv_nb_sectors() where sectors, not bytes are wanted
Instead of bdrv_getlength().

Aside: a few of these callers don't handle errors.  I didn't
investigate whether they should.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-15 15:07:13 +02:00
Kevin Wolf 3baca89139 block: Add Error argument to bdrv_refresh_limits()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-18 13:18:43 +01:00
Kevin Wolf 12ac6d3db7 qcow2: Fix error path for unknown incompatible features
qcow2's report_unsupported_feature() had two bugs: A 32 bit truncation
would prevent feature table entries for bits 32-63 from being used, and
it could assign errp multiple times if there was more than one unknown
feature, resulting in an error_set() assertion failure.

Fix the truncation, make sure to set the error exactly once and add a
qemu-iotests case for it.

This fixes https://bugs.launchpad.net/qemu/+bug/1342704/

Reported-by: Maria Kustova <maria.k@catit.be>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-07-18 13:12:15 +01:00
Kevin Wolf 44deba5a52 qcow2: Make qiov match request size until backing file EOF
If a qcow2 image has a shorter backing file and a read request to
unallocated clusters goes across EOF of the backing file, the backing
file sees a shortened request and the rest is filled with zeros.
However, the original too long qiov was used with the shortened request.

This patch makes the qiov size match the request size, avoiding a
potential buffer overflow in raw-posix.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2014-07-14 12:03:20 +02:00
Kevin Wolf 8ee79e707a block: Catch backing files assigned to non-COW drivers
Since we parse backing.* options to add a backing file from the command
line when the driver didn't assign one, it has been possible to have a
backing file for e.g. raw images (it just was never accessed).

This is obvious nonsense and should be rejected.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-06-26 13:51:01 +02:00
Chunyan Liu c282e1fdf7 cleanup QEMUOptionParameter
Now that all backend drivers are using QemuOpts, remove all
QEMUOptionParameter related codes.

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Chunyan Liu 1bd0e2d1c4 qcow2.c: replace QEMUOptionParameter with QemuOpts
Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:21 +08:00
Chunyan Liu 83d0521a1e change block layer to support both QemuOpts and QEMUOptionParamter
Change block layer to support both QemuOpts and QEMUOptionParameter.
After this patch, it will change backend drivers one by one. At the end,
QEMUOptionParameter will be removed and only QemuOpts is kept.

Signed-off-by: Dong Xu Wang <wdongxu@linux.vnet.ibm.com>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-16 17:23:20 +08:00
Markus Armbruster a1904e48c4 qcow2: Plug memory leak on qcow2_invalidate_cache() error paths
Introduced in commit 5a8a30d.  Spotted by Coverity.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-05-30 14:26:54 +02:00
Max Reitz 521b2b5df0 block: Use correct width in format strings
Instead of blindly relying on a normal integer having a width of 32 bits
(which is a pretty good assumption, but we should not rely on it if
there is no need), use the correct format string macros.

This does not touch DEBUG output.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-04-30 14:46:17 +02:00
Kevin Wolf 4c2e5f8f46 qcow2: Flush metadata during read-only reopen
If lazy refcounts are enabled for a backing file, committing to this
backing file may leave it in a dirty state even if the commit succeeds.
The reason is that the bdrv_flush() call in bdrv_commit() doesn't flush
refcount updates with lazy refcounts enabled, and qcow2_reopen_prepare()
doesn't take care to flush metadata.

In order to fix this, this patch also fixes qcow2_mark_clean(), which
contains another ineffective bdrv_flush() call beause lazy refcounts are
disabled only afterwards. All existing callers of qcow2_mark_clean()
either don't modify refcounts or already flush manually, so that this
fixes only a latent, but not yet actually triggerable bug.

Another instance of the same problem is live snapshots. Again, a real
corruption is prevented by an explicit flush for non-read-only images in
external_snapshot_prepare(), but images using lazy refcounts stay dirty.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-04 14:12:26 +02:00
Stefan Hajnoczi c792707f54 qcow2: link all L2 meta updates in preallocate()
preallocate() only links the first QCowL2Meta's data clusters into the
L2 table and ignores any chained QCowL2Metas in the linked list.

Chains of QCowL2Meta structs are built up when contiguous clusters span
L2 tables.  Each QCowL2Meta describes one L2 table update.  This is a
rare case in preallocate() but can happen.

This patch fixes preallocate() by iterating over the whole list of
QCowL2Metas.  Compare with the qcow2_co_writev() function's
implementation, which is similar but also also handles request
dependencies.  preallocate() only performs one allocation at a time so
there can be no dependencies.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 15:22:35 +02:00
Kevin Wolf 6a83f8b5be qcow2: Check maximum L1 size in qcow2_snapshot_load_tmp() (CVE-2014-0143)
This avoids an unbounded allocation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 15:22:35 +02:00
Kevin Wolf 11b128f406 qcow2: Fix NULL dereference in qcow2_open() error path (CVE-2014-0146)
The qcow2 code assumes that s->snapshots is non-NULL if s->nb_snapshots
!= 0. By having the initialisation of both fields separated in
qcow2_open(), any error occuring in between would cause the error path
to dereference NULL in qcow2_free_snapshots() if the image had any
snapshots.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 15:22:35 +02:00
Kevin Wolf 2b5d5953ee qcow2: Check new refcount table size on growth
If the size becomes larger than what qcow2_open() would accept, fail the
growing operation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 15:22:34 +02:00
Kevin Wolf b106ad9185 qcow2: Don't rely on free_cluster_index in alloc_refcount_block() (CVE-2014-0147)
free_cluster_index is only correct if update_refcount() was called from
an allocation function, and even there it's brittle because it's used to
protect unfinished allocations which still have a refcount of 0 - if it
moves in the wrong place, the unfinished allocation can be corrupted.

So not using it any more seems to be a good idea. Instead, use the
first requested cluster to do the calculations. Return -EAGAIN if
unfinished allocations could become invalid and let the caller restart
its search for some free clusters.

The context of creating a snapsnot is one situation where
update_refcount() is called outside of a cluster allocation. For this
case, the change fixes a buffer overflow if a cluster is referenced in
an L2 table that cannot be represented by an existing refcount block.
(new_table[refcount_table_index] was out of bounds)

[Bump the qemu-iotests 026 refblock_alloc.write leak count from 10 to
11.
--Stefan]

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 15:21:03 +02:00
Kevin Wolf 6d33e8e7dc qcow2: Fix backing file name length check
len could become negative and would pass the check then. Nothing bad
happened because bdrv_pread() happens to return an error for negative
length values, but make variables for sizes unsigned anyway.

This patch also changes the behaviour to error out on invalid lengths
instead of silently truncating it to 1023.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf 2d51c32c4b qcow2: Validate active L1 table offset and size (CVE-2014-0144)
This avoids an unbounded allocation.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf ce48f2f441 qcow2: Validate snapshot table offset/size (CVE-2014-0144)
This avoid unbounded memory allocation and fixes a potential buffer
overflow on 32 bit hosts.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf 8c7de28305 qcow2: Validate refcount table offset
The end of the refcount table must not exceed INT64_MAX so that integer
overflows are avoided.

Also check for misaligned refcount table. Such images are invalid and
probably the result of data corruption. Error out to avoid further
corruption.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf 5dab2faddc qcow2: Check refcount table size (CVE-2014-0144)
Limit the in-memory reference count table size to 8 MB, it's enough in
practice. This fixes an unbounded allocation as well as a buffer
overflow in qcow2_refcount_init().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf a1b3955c94 qcow2: Check backing_file_offset (CVE-2014-0144)
Header, header extension and the backing file name must all be stored in
the first cluster. Setting the backing file to a much higher value
allowed header extensions to become much bigger than we want them to be
(unbounded allocation).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Kevin Wolf 24342f2cae qcow2: Check header_length (CVE-2014-0144)
This fixes an unbounded allocation for s->unknown_header_fields.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 14:19:09 +02:00
Prasad Joshi c5a33ee9ee qcow2: fix two memory leaks in qcow2_open error code path
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-01 13:49:53 +02:00
Kevin Wolf 5a8a30db47 block: Add error handling to bdrv_invalidate_cache()
If it returns an error, the migrated VM will not be started, but qemu
exits with an error message.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-03-19 09:39:41 +01:00
Kevin Wolf 27eb6c097c qcow2: Don't write with BDRV_O_INCOMING
qcow2_open() causes writes when repairing an image with the dirty flag
set and when clearing autoclear flags. It shouldn't do this when another
qemu instance is still actively working on this image file.

One effect of the bug is that images may have a cleared dirty flag while
the migration source host still has it in use with lazy refcounts
enabled, so refcounts are not accurate and the dirty flag must remain
set.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:42:24 +01:00
Kevin Wolf d475e5acd2 qcow2: Keep option in qcow2_invalidate_cache()
Instead of manually building a list of all options from BDRVQcowState
values just reuse the options that were used to open the image.
qcow2_open() won't fully use all of the options in the QDict, but that's
okay.

This fixes all of the driver-specific options in qcow2, except for
lazy-refcounts, which was special cased before.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:42:24 +01:00
Kevin Wolf 3456a8d185 block: Update image size in bdrv_invalidate_cache()
After migration has completed, we call bdrv_invalidate_cache() so that
drivers which cache some data drop their stale copy of the data and
reread it from the image file to get a new version of data that the
source modified while the migration was running.

Reloading metadata from the image file is useless, though, if the size
of the image file stays stale (this is a value that is cached for all
image formats in block.c). Reads from (meta)data after the old EOF
return only zeroes, causing image corruption.

We need to update bs->total_sectors in all layers that could potentially
have changed their size (i.e. backing files are not a concern - if they
are changed, we're in bigger trouble)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-13 14:23:27 +01:00
Paolo Bonzini 76abe4071d block: do not abuse EMEDIUMTYPE
Returning "Wrong medium type" for an image that does not have a valid
header is a bit weird.  Improve the error by mentioning what format
was trying to open it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:24 +01:00
Max Reitz 2e40134bfd block: Make bdrv_file_open() static
Add the bdrv_open() option BDRV_O_PROTOCOL which results in passing the
call to bdrv_file_open(). Additionally, make bdrv_file_open() static and
therefore bdrv_open() the only way to call it.

Consequently, all existing calls to bdrv_file_open() have to be adjusted
to use bdrv_open() with the BDRV_O_PROTOCOL flag instead.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:22 +01:00
Max Reitz ddf5636dc9 block: Add reference parameter to bdrv_open()
Allow bdrv_open() to handle references to existing block devices just as
bdrv_file_open() is already capable of.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:22 +01:00
Max Reitz f67503e5bd block: Change BDS parameter of bdrv_open() to **
Make bdrv_open() take a pointer to a BDS pointer, similarly to
bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open()
will create a new BDS with an empty name; if the BDS pointer is not
NULL, that existing BDS will be reused (in the same way as bdrv_open()
already did).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21 21:02:21 +01:00
Markus Armbruster 84d18f065f Use error_is_set() only when necessary
error_is_set(&var) is the same as var != NULL, but it takes
whole-program analysis to figure that out.  Unnecessarily hard for
optimizers, static checkers, and human readers.  Dumb it down to
obvious.

Gets rid of several dozen Coverity false positives.

Note that the obvious form is already used in many places.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-02-17 11:57:23 -05:00
Hu Tao 7c2bbf4aa6 qcow2: check for NULL l2meta
In the case of a metadata preallocation with a large cluster size,
qcow2_alloc_cluster_offset() can allocate nothing and returns a
NULL l2meta. This patch checks for it and link2 l2 with only valid
l2meta.

Replace 9 and 512 with BDRV_SECTOR_BITS, BDRV_SECTOR_SIZE
respectively while at the function.

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-09 09:12:39 +01:00
Hu Tao 16f0587e0a qcow2: remove n_start and n_end of qcow2_alloc_cluster_offset()
n_start can be actually calculated from offset. The number of
sectors to be allocated(n_end - n_start) can be passed in in
num. By removing n_start and n_end, we can save two parameters.

The side effect is there is a bug in qcow2.c:preallocate() that
passes incorrect n_start to qcow2_alloc_cluster_offset() is
fixed. The bug can be triggerred by a larger cluster size than
the default value(65536), for example:

./qemu-img create -f qcow2 \
  -o 'cluster_size=131072,preallocation=metadata' file.img 4G

Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-09 09:12:39 +01:00
Jeff Cody 14b4a8b9c6 block: remove qcow2 .bdrv_make_empty implementation
The QCOW2 .bdrv_make_empty implementation always returns 0 for success,
but does not actually do anything.

The proper way to not support an optional driver function stub is to
just not implement it, so let's remove the stub.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-01-31 22:05:03 +01:00
Kevin Wolf d34682cd4a block: Move initialisation of BlockLimits to bdrv_refresh_limits()
This function separates filling the BlockLimits from bdrv_open(), which
allows it to call it from other operations which may change the limits
(e.g. modifications to the backing file chain or bdrv_reopen)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24 17:40:01 +01:00
Max Reitz 72daa72eee block: Allow reference for bdrv_file_open()
Allow specifying a reference to an existing block device (by name) for
bdrv_file_open() instead of a filename and/or options.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-01-22 12:07:17 +01:00
Peter Crosthwaite 87ea75d5e1 qemu-option: Remove qemu_opts_create_nofail
This is a boiler-plate _nofail variant of qemu_opts_create. Remove and
use error_abort in call sites.

null/0 arguments needs to be added for the id and fail_if_exists fields
in affected callsites due to argument inconsistency between the normal and
no_fail variants.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-01-06 15:02:30 -05:00
Kevin Wolf f8413b3c23 qcow2: Zero-initialise first cluster for new images
Strictly speaking, this is only required for has_zero_init() == false,
but it's easy enough to just do a cluster-aligned write that is padded
with zeros after the header.

This fixes that after 'qemu-img create' header extensions are attempted
to be parsed that are really just random leftover data.

Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-04 11:29:37 +01:00
Paolo Bonzini cffb1ec600 block drivers: expose requirement for write same alignment from formats
This will let misaligned but large requests use zero clusters.  This
is important because the cluster size is not guest visible.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-03 15:26:49 +01:00
Paolo Bonzini 95de6d7078 block drivers: add discard/write_zeroes properties to bdrv_get_info implementation
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-03 15:26:49 +01:00
Kevin Wolf c9fbb99d41 block: Use BDRV_O_NO_BACKING where appropriate
If you open an image temporarily just because you want to check its size
or get it flushed, there's no real reason to open the whole backing file
chain.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2013-11-29 17:41:09 +01:00
Peter Lieven aa7bfbfff7 block: add flags to bdrv_*_write_zeroes
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28 10:30:51 +01:00
Max Reitz ba2ab2f2ca qcow2: Flush image after creation
Opening the qcow2 image with BDRV_O_NO_FLUSH prevents any flushes during
the image creation. This means that the image has not yet been flushed
to disk when qemu-img create exits. This flush is delayed until the next
operation on the image involving opening it without BDRV_O_NO_FLUSH and
closing (or directly flushing) it. For large images and/or images with a
small cluster size and preallocated metadata, this flush may take a
significant amount of time and may occur unexpectedly.

Reopening the image without BDRV_O_NO_FLUSH right before the end of
qcow2_create2() results in hoisting the potentially costly flush into
the image creation, which is expected to take some time (whereas
successive image operations may be not).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-28 17:34:32 +01:00
Max Reitz 6e13610aa4 qcow2: Unset zero_beyond_eof in save_vmstate
Saving the VM state is done using bdrv_pwrite. This function may perform
a read-modify-write, which in this case results in data being read from
beyond the end of the virtual disk. Since we are actually trying to
access an area which is not a part of the virtual disk, zero_beyond_eof
has to be set to false before performing the partial write, otherwise
the VM state may become corrupted.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-24 11:50:51 +02:00
Max Reitz eedff66f21 qcow2: Restore total_sectors value in save_vmstate
Since df2a6f29a5, bdrv_co_do_writev increases the total_sectors value of
a growable block devices on writes after the current end. This leads to
the virtual disk apparently growing in qcow2_save_vmstate, which in turn
affects the disk size captured by the internal snapshot taken directly
afterwards through e.g. the HMP savevm command. Such a "grown" snapshot
cannot be loaded after reopening the qcow2 image, since its disk size
differs from the actual virtual disk size (writing a VM state does not
actually increase the virtual disk size).

Fix this by restoring total_sectors at the end of qcow2_save_vmstate.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-24 11:45:06 +02:00
Max Reitz 1fa5cc839a qcow2: Evaluate overlap check options
Evaluate the runtime overlap check options and set
BDRVQcowState.overlap_check appropriately.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz 4092e99d93 qcow2: Array assigning options to OL check bits
Add an array which assigns the option string to its corresponding
overlap check bit.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz 05de7e86ca qcow2: Add overlap-check options
Add runtime options to tune the overlap checks to be performed before
write accesses.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz 3e3553905c qcow2: Make overlap check mask variable
Replace the QCOW2_OL_DEFAULT macro by a variable overlap_check in
BDRVQcowState.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz 231bb26764 qcow2: Use negated overflow check mask
In qcow2_check_metadata_overlap and qcow2_pre_write_overlap_check,
change the parameter signifying the checks to perform from its current
positive form to a negative one, i.e., it will no longer explicitly
specify every check to perform but rather a mask of checks not to
perform.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:50:00 +02:00
Max Reitz f9bff97143 qcow2: Remove wrong metadata overlap check
In qcow2_write_compressed, if the compression fails, a normal cluster is
written to disk. This is done through bdrv_write on the qcow2 BDS
itself (using the guest offset), thus it is wrong to do a metadata
overlap check before.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 16:49:59 +02:00