This function deletes a snapshot from disk, removing its entry from
the snapshot table, freeing its L1 table and decreasing the refcounts
of all clusters.
The L1 table offset and size are however not validated. If we use
invalid values in this function we'll probably corrupt the image even
more, so we should return an error instead.
We now have a function to take care of this, so let's use it.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function copies a snapshot's L1 table into the active one without
validating it first.
We now have a function to take care of this, so let's use it.
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The inactive-l2 overlap check iterates uses the L1 tables from all
snapshots, but it does not validate them first.
We now have a function to take care of this, so let's use it.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function iterates over all snapshots of a qcow2 file in order to
expand all zero clusters, but it does not validate the snapshots' L1
tables first.
We now have a function to take care of this, so let's use it.
We can also take the opportunity to replace the sector-based
bdrv_read() with bdrv_pread().
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function checks that the size of a snapshot's L1 table is not too
large, but it doesn't validate the offset.
We now have a function to take care of this, so let's use it.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This function checks that the offset and size of a table are valid.
While the offset checks are fine, the size check is too generic, since
it only verifies that the total size in bytes fits in a 64-bit
integer. In practice all tables used in qcow2 have much smaller size
limits, so the size needs to be checked again for each table using its
actual limit.
This patch generalizes this function by allowing the caller to specify
the maximum size for that table. In addition to that it allows passing
an Error variable.
The function is also renamed and made public since we're going to use
it in other parts of the code.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-8-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
QED's bdrv_invalidate_cache implementation would like to reuse functions
that acquire/release the metadata locks. Call it from coroutine context
to simplify the logic.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-6-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is called from qed_invalidate_cache in coroutine context (incoming
migration runs in a coroutine), so it's cleaner if metadata is always
loaded from a coroutine.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-5-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is called from qcow2_invalidate_cache in coroutine context (incoming
migration runs in a coroutine), so it's cleaner if metadata is always
loaded from a coroutine.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-4-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
update_header_sync itself does not need to flush the caches to disk.
The only paths that allocate clusters are:
- bitmap_list_store with in_place=false, called by update_ext_header_and_dir
- store_bitmap_data, called by store_bitmap
- store_bitmap, called by qcow2_store_persistent_dirty_bitmaps and
followed by update_ext_header_and_dir
So in the end the central place where we need to flush the caches
is update_ext_header_and_dir.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
They will be used to avoid recursively taking s->lock during
bdrv_open or bdrv_check.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1516279431-30424-7-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If the bdrv_reopen_prepare helper isn't provided, the qemu-img commit
command fails to re-open the base layer after committing changes into
it. Provide a no-op implementation for the LUKS driver, since there
is not any custom work that needs doing to re-open it.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Starting qemu with the following arguments causes qemu to segfault:
... -device lsi,id=lsi0 -drive file=iscsi:<...>,format=raw,if=none,node-name=
iscsi1 -device scsi-block,bus=lsi0.0,id=<...>,drive=iscsi1
This patch fixes blk_aio_ioctl() so it does not pass stack addresses to
blk_aio_ioctl_entry() which may be invoked after blk_aio_ioctl() returns. More
details about the bug follow.
blk_aio_ioctl() invokes blk_aio_prwv() with blk_aio_ioctl_entry as the
coroutine parameter. blk_aio_prwv() ultimately calls aio_co_enter().
When blk_aio_ioctl() is executed from within a coroutine context (e.g.
iscsi_bh_cb()), aio_co_enter() adds the coroutine (blk_aio_ioctl_entry) to
the current coroutine's wakeup queue. blk_aio_ioctl() then returns.
When blk_aio_ioctl_entry() executes later, it accesses an invalid pointer:
....
BlkRwCo *rwco = &acb->rwco;
rwco->ret = blk_co_ioctl(rwco->blk, rwco->offset,
rwco->qiov->iov[0].iov_base); <--- qiov is
invalid here
...
In the case when blk_aio_ioctl() is called from a non-coroutine context,
blk_aio_ioctl_entry() executes immediately. But if bdrv_co_ioctl() calls
qemu_coroutine_yield(), blk_aio_ioctl() will return. When the coroutine
execution is complete, control returns to blk_aio_ioctl_entry() after the call
to blk_co_ioctl(). There is no invalid reference after this point, but the
function is still holding on to invalid pointers.
The fix is to change blk_aio_prwv() to accept a void pointer for the IO buffer
rather than a QEMUIOVector. blk_aio_prwv() passes this through in BlkRwCo and the
coroutine function casts it to QEMUIOVector or uses the void pointer directly.
Signed-off-by: Deepa Srinivasan <deepa.srinivasan@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
# gpg: Signature made Mon 05 Mar 2018 17:45:51 GMT
# gpg: using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (38 commits)
block: Fix NULL dereference on empty drive error
qcow2: Replace align_offset() with ROUND_UP()
block/ssh: Add basic .bdrv_truncate()
block/ssh: Make ssh_grow_file() blocking
block/ssh: Pull ssh_grow_file() from ssh_create()
qemu-img: Make resize error message more general
qcow2: make qcow2_co_create2() a coroutine_fn
block: rename .bdrv_create() to .bdrv_co_create_opts()
Revert "IDE: Do not flush empty CDROM drives"
block: test blk_aio_flush() with blk->root == NULL
block: add BlockBackend->in_flight counter
block: extract AIO_WAIT_WHILE() from BlockDriverState
aio: rename aio_context_in_iothread() to in_aio_context_home_thread()
docs: document how to use the l2-cache-entry-size parameter
specs/qcow2: Fix documentation of the compressed cluster descriptor
iotest 033: add misaligned write-zeroes test via truncate
block: fix write with zero flag set and iovector provided
block: Drop unused .bdrv_co_get_block_status()
vvfat: Switch to .bdrv_co_block_status()
vpc: Switch to .bdrv_co_block_status()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
# Conflicts:
# include/block/block.h
blk_error_action() sends a BLOCK_IO_ERROR QMP event which includes the
node name of its root node. If the BlockBackend represents an empty
drive, there is no root node, so we should not try to access its node
name. Make the field optional in the event and include it only when
the BlockBackend isn't empty.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The previous commit improved compile time by including less of the
generated QAPI headers. This is impossible for stuff defined directly
in qapi-schema.json, because that ends up in headers that that pull in
everything.
Move everything but include directives from qapi-schema.json to new
sub-module qapi/misc.json, then include just the "misc" shard where
possible.
It's possible everywhere, except:
* monitor.c needs qmp-command.h to get qmp_init_marshal()
* monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need
qapi-event.h to get enum QAPIEvent
Perhaps we'll get rid of those some other day.
Adding a type to qapi/migration.json now recompiles some 120 instead
of 2300 out of 5100 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-25-armbru@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
In my "build everything" tree, a change to the types in
qapi-schema.json triggers a recompile of about 4800 out of 5100
objects.
The previous commit split up qmp-commands.h, qmp-event.h, qmp-visit.h,
qapi-types.h. Each of these headers still includes all its shards.
Reduce compile time by including just the shards we actually need.
To illustrate the benefits: adding a type to qapi/migration.json now
recompiles some 2300 instead of 4800 objects. The next commit will
improve it further.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-24-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
The align_offset() function is equivalent to the ROUND_UP() macro so
there's no need to use the former. The ROUND_UP() name is also a bit
more explicit.
This patch uses ROUND_UP() instead of the slower QEMU_ALIGN_UP()
because align_offset() already requires that the second parameter is a
power of two.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180215131008.5153-1-berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
libssh2 does not seem to offer real truncation support, so we can only
grow files -- but that is better than nothing.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180214204915.7980-4-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
At runtime (that is, during a future ssh_truncate()), the SSH session is
non-blocking. However, ssh_truncate() (or rather, bdrv_truncate() in
general) is not a coroutine, so this resize operation needs to block.
For ssh_create(), that is fine, too; the session is never set to
non-blocking anyway.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180214204915.7980-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If we ever want to offer even rudimentary truncation functionality for
ssh, we should put the respective code into a reusable function.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20180214204915.7980-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_create2() calls qemu_co_mutex_lock(). Only a coroutine_fn may
call another coroutine_fn. In fact, qcow2_create2 is always called from
coroutine context.
Rename the function to add the "co" moniker and add coroutine_fn.
Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170705102231.20711-3-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
BlockDriver->bdrv_create() has been called from coroutine context since
commit 5b7e1542cf ("block: make
bdrv_create adopt coroutine").
Make this explicit by renaming to .bdrv_co_create_opts() and add the
coroutine_fn annotation. This makes it obvious to block driver authors
that they may yield, use CoMutex, or other coroutine_fn APIs.
bdrv_co_create is reserved for the QAPI-based version that Kevin is
working on.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170705102231.20711-2-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
BlockBackend currently relies on BlockDriverState->in_flight to track
requests for blk_drain(). There is a corner case where
BlockDriverState->in_flight cannot be used though: blk->root can be NULL
when there is no medium. This results in a segfault when the NULL
pointer is dereferenced.
Introduce a BlockBackend->in_flight counter for aio requests so it works
even when blk->root == NULL.
Based on a patch by Kevin Wolf <kwolf@redhat.com>.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
BlockDriverState has the BDRV_POLL_WHILE() macro to wait on event loop
activity while a condition evaluates to true. This is used to implement
synchronous operations where it acts as a condvar between the IOThread
running the operation and the main loop waiting for the operation. It
can also be called from the thread that owns the AioContext and in that
case it's just a nested event loop.
BlockBackend needs this behavior but doesn't always have a
BlockDriverState it can use. This patch extracts BDRV_POLL_WHILE() into
the AioWait abstraction, which can be used with AioContext and isn't
tied to BlockDriverState anymore.
This feature could be built directly into AioContext but then all users
would kick the event loop even if they signal different conditions.
Imagine an AioContext with many BlockDriverStates, each time a request
completes any waiter would wake up and re-check their condition. It's
nicer to keep a separate AioWait object for each condition instead.
Please see "block/aio-wait.h" for details on the API.
The name AIO_WAIT_WHILE() avoids the confusion between AIO_POLL_WHILE()
and AioContext polling.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The normal bdrv_co_pwritev() use is either
- BDRV_REQ_ZERO_WRITE clear and iovector provided
- BDRV_REQ_ZERO_WRITE set and iovector == NULL
while
- the flag clear and iovector == NULL is an assertion failure
in bdrv_co_do_zero_pwritev()
- the flag set and iovector provided is in fact allowed
(the flag prevails and zeroes are written)
However the alignment logic does not support the latter case so the padding
areas get overwritten with zeroes.
Currently, general functions like bdrv_rw_co() do provide iovector
regardless of flags. So, keep it supported and use bdrv_co_do_zero_pwritev()
alignment for it which also makes the code a bit more obvious anyway.
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Now that all drivers have been updated to provide the
byte-based .bdrv_co_block_status(), we can delete the sector-based
interface.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the vvfat driver accordingly. Note that we
can rely on the block driver having already clamped limits to our
block size, and simplify accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the vpc driver accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the vmdk driver accordingly. Drop the
now-unused vmdk_find_index_in_cluster().
Also, fix a pre-existing bug: if find_extent() fails (unlikely,
since the block layer did a bounds check), then we must return a
failure, rather than 0.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the vdi driver accordingly. Note that the
TODO is already covered (the block layer guarantees bounds of its
requests), and that we can remove the now-unused s->block_sectors.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Rework the debug define so that we always get -Wformat checking,
even when debugging is disabled.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the sheepdog driver accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the raw driver accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the qed driver accordingly, taking the opportunity
to inline qed_is_allocated_cb() into its lone caller (the callback
used to be important, until we switched qed to coroutines). There is
no intent to optimize based on the want_zero flag for this format.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the qcow2 driver accordingly.
For now, we are ignoring the 'want_zero' hint. However, it should
be relatively straightforward to honor the hint as a way to return
larger *pnum values when we have consecutive clusters with the same
data/zero status but which differ only in having non-consecutive
mappings.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the qcow driver accordingly. There is no
intent to optimize based on the want_zero flag for this format.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the parallels driver accordingly. Note that
the internal function block_status() is still sector-based, because
it is still in use by other sector-based functions; but that's okay
because request_alignment is 512 as a result of those functions.
For now, no optimizations are added based on the mapping hint.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the null driver accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the iscsi driver accordingly. In this case,
it is handy to teach iscsi_co_block_status() to handle a NULL map
and file parameter, even though the block layer passes non-NULL
values, because we also call the function directly. For now, there
are no optimizations done based on the want_zero flag.
We can also make the simplification of asserting that the block
layer passed in aligned values.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert all uses of
the allocmap (no semantic change). Callers that already had bytes
available are simpler, and callers that now scale to bytes will be
easier to switch to byte-based in the future.
Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert all uses of
the cluster size in sectors, along with adding assertions that we
are not dividing by zero.
Improve some comment grammar while in the area.
Signed-off-by: Eric Blake <eblake@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the gluster driver accordingly.
In want_zero mode, we continue to report fine-grained hole
information (the caller wants as much mapping detail as possible);
but when not in that mode, the caller prefers larger *pnum and
merely cares about what offsets are allocated at this layer, rather
than where the holes live. Since holes still read as zeroes at
this layer (rather than deferring to a backing layer), we can take
the shortcut of skipping find_allocation(), and merely state that
all bytes are allocated.
We can also drop redundant bounds checks that are already
guaranteed by the block layer.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the file protocol driver accordingly.
In want_zero mode, we continue to report fine-grained hole
information (the caller wants as much mapping detail as possible);
but when not in that mode, the caller prefers larger *pnum and
merely cares about what offsets are allocated at this layer, rather
than where the holes live. Since holes still read as zeroes at
this layer (rather than deferring to a backing layer), we can take
the shortcut of skipping lseek(), and merely state that all bytes
are allocated.
We can also drop redundant bounds checks that are already
guaranteed by the block layer.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Update the generic helpers, and all passthrough clients
(blkdebug, commit, mirror, throttle) accordingly.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit bdd6a90 has a bug: drivers should never directly set
BDRV_BLOCK_ALLOCATED, but only io.c should do that (as needed).
Instead, drivers should report BDRV_BLOCK_DATA if it knows that
data comes from this BDS.
But let's look at the bigger picture: semantically, the nvme
driver is similar to the nbd, null, and raw drivers (no backing
file, all data comes from this BDS). But while two of those
other drivers have to supply the callback (null because it can
special-case BDRV_BLOCK_ZERO, raw because it can special-case
a different offset), in this case the block layer defaults are
good enough without the callback at all (similar to nbd).
So, fix the bug by deletion ;)
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. Now that the block layer exposes byte-based allocation,
it's time to tackle the drivers. Add a new callback that operates
on as small as byte boundaries. Subsequent patches will then update
individual drivers, then finally remove .bdrv_co_get_block_status().
The new code also passes through the 'want_zero' hint, which will
allow subsequent patches to further optimize callers that only care
about how much of the image is allocated (want_zero is false),
rather than full details about runs of zeroes and which offsets the
allocation actually maps to (want_zero is true). As part of this
effort, fix another part of the documentation: the claim in commit
4c41cb4 that BDRV_BLOCK_ALLOCATED is short for 'DATA || ZERO' is a
lie at the block layer (see commit e88ae2264), even though it is
how the bit is computed from the driver layer. After all, there
are intentionally cases where we return ZERO but not ALLOCATED at
the block layer, when we know that a read sees zero because the
backing file is too short. Note that the driver interface is thus
slightly different than the public interface with regards to which
bits will be set, and what guarantees are provided on input.
We also add an assertion that any driver using the new callback will
make progress (the only time pnum will be 0 is if the block layer
already handled an out-of-bounds request, or if there is an error);
the old driver interface did not provide this guarantee, which
could lead to some inf-loops in drastic corner-case failures.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit 79ba8c98 (v2.7) changed the setting of request_alignment
to occur only during bdrv_refresh_limits(), rather than at at
bdrv_open() time; but at the time, NBD was unaffected, because
it still used sector-based callbacks, so the block layer
defaulted NBD to use 512 request_alignment.
Later, commit 70c4fb26 (also v2.7) changed NBD to use byte-based
callbacks, without setting request_alignment. This resulted in
NBD using request_alignment of 1, which works great when the
server supports it (as is the case for qemu-nbd), but falls apart
miserably if the server requires alignment (but only if qemu
actually sends a sub-sector request; qemu-io can do it, but
most qemu operations still perform on sectors or larger).
Even later, the NBD protocol was updated to document that clients
should learn the server's minimum alignment during NBD_OPT_GO;
and recommended that clients should assume a minimum size of 512
unless the server understands NBD_OPT_GO and replied with a smaller
size. Commit 081dd1fe (v2.10) attempted to do that, by assigning
request_alignment to whatever was learned from the server; but
it has two flaws: the assignment is done during bdrv_open() so
it gets unconditionally wiped out back to 1 during any later
bdrv_refresh_limits(); and the code is not using a default of 512
when the server did not report a minimum size.
Fix these issues by moving the assignment to request_alignment
to the right function, and by using a sane default when the
server does not advertise a minimum size.
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180215032905.27146-1-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com>
1) string not null terminated in sysfs_find_group_file
2) NULL pointer dereference and dead local variable in nvme_init.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180213015240.9352-1-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Now that the code is ready to handle L2 slices we can finally add an
option to allow configuring their size.
An L2 slice is the portion of an L2 table that is read by the qcow2
cache. Until now the cache was always reading full L2 tables, and
since the L2 table size is equal to the cluster size this was not very
efficient with large clusters. Here's a more detailed explanation of
why it makes sense to have smaller cache entries in order to load L2
data:
https://lists.gnu.org/archive/html/qemu-block/2017-09/msg00635.html
This patch introduces a new command-line option to the qcow2 driver
named l2-cache-entry-size (cf. l2-cache-size). The cache entry size
has the same restrictions as the cluster size: it must be a power of
two and it has the same range of allowed values, with the additional
requirement that it must not be larger than the cluster size.
The L2 cache entry size (L2 slice size) remains equal to the cluster
size for now by default, so this feature must be explicitly enabled.
Although my tests show that 4KB slices consistently improve
performance and give the best results, let's wait and make more tests
with different cluster sizes before deciding on an optimal default.
Now that the cache entry size is not necessarily equal to the cluster
size we need to reflect that in the MIN_L2_CACHE_SIZE documentation.
That minimum value is a requirement of the COW algorithm: we need to
read two L2 slices (and not two L2 tables) in order to do COW, see
l2_allocate() for the actual code.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: c73e5611ff4a9ec5d20de68a6c289553a13d2354.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function doesn't need any changes to support L2 slices, but since
it's now dealing with slices intead of full tables, the l2_table
variable is renamed for clarity.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 6107001fc79e6739242f1de7d191375e4f130aac.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function doesn't need any changes to support L2 slices, but since
it's now dealing with slices instead of full tables, the l2_table
variable is renamed for clarity.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 78bcc54bc632574dd0b900a77a00a1b6ffc359e6.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function doesn't need any changes to support L2 slices, but since
it's now dealing with slices intead of full tables, the l2_table
variable is renamed for clarity.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 812b0c3505bb1687e51285dccf1a94f0cecb1f74.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function doesn't need any changes to support L2 slices, but since
it's now dealing with slices instead of full tables, the l2_table
variable is renamed for clarity.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 0c5d4b9bf163aa3b49ec19cc512a50d83563f2ad.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The qcow2_truncate() code is mostly independent from whether
we're using L2 slices or full L2 tables, but in full and
falloc preallocation modes new L2 tables are allocated using
qcow2_alloc_cluster_link_l2(). Therefore the code needs to be
modified to ensure that all nb_clusters that are processed in each
call can be allocated with just one L2 slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 1fd7d272b5e7b66254a090b74cf2bed1cc334c0e.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
expand_zero_clusters_in_l1() expands zero clusters as a necessary step
to downgrade qcow2 images to a version that doesn't support metadata
zero clusters. This function takes an L1 table (which may or may not
be active) and iterates over all its L2 tables looking for zero
clusters.
Since we'll be loading L2 slices instead of full tables we need to add
an extra loop that iterates over all slices of each L2 table, and we
should also use the slice size when allocating the buffer used when
the L1 table is not active.
This function doesn't need any additional changes so apart from that
this patch simply updates the variable name from l2_table to l2_slice.
Finally, and since we have to touch the bdrv_read() / bdrv_write()
calls anyway, this patch takes the opportunity to replace them with
the byte-based bdrv_pread() / bdrv_pwrite().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 43590976f730501688096cff103f2923b72b0f32.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Adding support for L2 slices to expand_zero_clusters_in_l1() needs
(among other things) an extra loop that iterates over all slices of
each L2 table.
Putting all changes in one patch would make it hard to read because
all semantic changes would be mixed with pure indentation changes.
To make things easier this patch simply creates a new block and
changes the indentation of all lines of code inside it. Thus, all
modifications in this patch are cosmetic. There are no semantic
changes and no variables are renamed yet. The next patch will take
care of that.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: c2ae9f31ed5b6e591477ad4654448badd1c89d73.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
At the moment it doesn't really make a difference whether we call
qcow2_get_refcount() before of after reading the L2 table, but if we
want to support L2 slices we'll need to read the refcount first.
This patch simply changes the order of those two operations to prepare
for that. The patch with the actual semantic changes will be easier to
read because of this.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 947a91d934053a2dbfef979aeb9568f57ef57c5d.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_update_snapshot_refcount() increases the refcount of all
clusters of a given snapshot. In order to do that it needs to load all
its L2 tables and iterate over their entries. Since we'll be loading
L2 slices instead of full tables we need to add an extra loop that
iterates over all slices of each L2 table.
This function doesn't need any additional changes so apart from that
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 5f4db199b9637f4833b58487135124d70add8cf0.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Adding support for L2 slices to qcow2_update_snapshot_refcount() needs
(among other things) an extra loop that iterates over all slices of
each L2 table.
Putting all changes in one patch would make it hard to read because
all semantic changes would be mixed with pure indentation changes.
To make things easier this patch simply creates a new block and
changes the indentation of all lines of code inside it. Thus, all
modifications in this patch are cosmetic. There are no semantic
changes and no variables are renamed yet. The next patch will take
care of that.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 8ffaa5e55bd51121f80e498f4045b64902a94293.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
zero_single_l2() limits the number of clusters to be zeroed to the
amount that fits inside an L2 table. Since we'll be loading L2 slices
instead of full tables we need to update that limit. The function is
renamed to zero_in_l2_slice() for clarity.
Apart from that, this function doesn't need any additional changes, so
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: ebc16e7e79fa6969d8975ef487d679794de4fbcc.1517840877.git.berto@igalia.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
discard_single_l2() limits the number of clusters to be discarded
to the amount that fits inside an L2 table. Since we'll be loading
L2 slices instead of full tables we need to update that limit. The
function is renamed to discard_in_l2_slice() for clarity.
Apart from that, this function doesn't need any additional changes, so
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 1cb44a5b68be5334cb01b97a3db3a3c5a43396e5.1517840877.git.berto@igalia.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
handle_alloc() loads an L2 table and limits the number of checked
clusters to the amount that fits inside that table. Since we'll be
loading L2 slices instead of full tables we need to update that limit.
Apart from that, this function doesn't need any additional changes, so
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: b243299c7136f7014c5af51665431ddbf5e99afd.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
handle_copied() loads an L2 table and limits the number of checked
clusters to the amount that fits inside that table. Since we'll be
loading L2 slices instead of full tables we need to update that limit.
Apart from that, this function doesn't need any additional changes, so
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 541ac001a7d6b86bab2392554bee53c2b312148c.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
There's a loop in this function that iterates over the L2 entries in a
table, so now we need to assert that it remains within the limits of
an L2 slice.
Apart from that, this function doesn't need any additional changes, so
this patch simply updates the variable name from l2_table to l2_slice.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: f9846a1c2efc51938e877e2a25852d9ab14797ff.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_get_cluster_offset() checks how many contiguous bytes are
available at a given offset. The returned number of bytes is limited
by the amount that can be addressed without having to load more than
one L2 table.
Since we'll be loading L2 slices instead of full tables this patch
changes the limit accordingly using the size of the L2 slice for the
calculations instead of the full table size.
One consequence of this is that with small L2 slices operations such
as 'qemu-img map' will need to iterate in more steps because each
qcow2_get_cluster_offset() call will potentially return a smaller
number. However the code is already prepared for that so this doesn't
break semantics.
The l2_table variable is also renamed to l2_slice to reflect this, and
offset_to_l2_index() is replaced with offset_to_l2_slice_index().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 6b602260acb33da56ed6af9611731cb7acd110eb.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This patch updates get_cluster_table() to return L2 slices instead of
full L2 tables.
The code itself needs almost no changes, it only needs to call
offset_to_l2_slice_index() instead of offset_to_l2_index(). This patch
also renames all the relevant variables and the documentation.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 64cf064c0021ba315d3f3032da0f95db1b615f33.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
After the previous patch we're now always using l2_load() in
get_cluster_table() regardless of whether a new L2 table has to be
allocated or not.
This patch refactors that part of the code to use one single l2_load()
call.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: ce31758c4a1fadccea7a6ccb93951eb01d95fd4c.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This patch updates l2_allocate() to support the qcow2 cache returning
L2 slices instead of full L2 tables.
The old code simply gets an L2 table from the cache and initializes it
with zeroes or with the contents of an existing table. With a cache
that returns slices instead of tables the idea remains the same, but
the code must now iterate over all the slices that are contained in an
L2 table.
Since now we're operating with slices the function can no longer
return the newly-allocated table, so it's up to the caller to retrieve
the appropriate L2 slice after calling l2_allocate() (note that with
this patch the caller is still loading full L2 tables, but we'll deal
with that in a separate patch).
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20fc0415bf0e011e29f6487ec86eb06a11f37445.1517840877.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Adding support for L2 slices to l2_allocate() needs (among other
things) an extra loop that iterates over all slices of a new L2 table.
Putting all changes in one patch would make it hard to read because
all semantic changes would be mixed with pure indentation changes.
To make things easier this patch simply creates a new block and
changes the indentation of all lines of code inside it. Thus, all
modifications in this patch are cosmetic. There are no semantic
changes and no variables are renamed yet. The next patch will take
care of that.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: d0d7dca8520db304524f52f49d8157595a707a35.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Each entry in the qcow2 L2 cache stores a full L2 table (which uses a
complete cluster in the qcow2 image). A cluster is usually too large
to be used efficiently as the size for a cache entry, so we want to
decouple both values by allowing smaller cache entries. Therefore the
qcow2 L2 cache will no longer return full L2 tables but slices
instead.
This patch updates l2_load() so it can handle L2 slices correctly.
Apart from the offset of the L2 table (which we already had) we also
need the guest offset in order to calculate which one of the slices
we need.
An L2 slice has currently the same size as an L2 table (one cluster),
so for now this function will load exactly the same data as before.
This patch also removes a stale comment about the return value being
a pointer to the L2 table. This function returns an error code since
55c17e9821.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: b830aa1fc5b6f8e3cb331d006853fe22facca847.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Similar to offset_to_l2_index(), this function takes a guest offset
and returns the index in the L2 slice that contains its L2 entry.
An L2 slice has currently the same size as an L2 table (one cluster),
so both functions return the same value for now.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a1c45c5c5a76146dd1712d8d1e7b409ad539c718.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The BDRVQcow2State structure contains an l2_size field, which stores
the number of 64-bit entries in an L2 table.
For efficiency reasons we want to be able to load slices instead of
full L2 tables, so we need to know how many entries an L2 slice can
hold.
An L2 slice is the portion of an L2 table that is loaded by the qcow2
cache. At the moment that cache can only load complete tables,
therefore an L2 slice has the same size as an L2 table (one cluster)
and l2_size == l2_slice_size.
Later we'll allow smaller slices, but until then we have to use this
new l2_slice_size field to make the rest of the code ready for that.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: adb048595f9fb5dfb110c802a8b3c3be3b937f37.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Similar to offset_to_l2_index(), this function returns the index in
the L1 table for a given guest offset. This is only used in a couple
of places and it's not a particularly complex calculation, but it
makes the code a bit more readable.
Although in the qcow2_get_cluster_offset() case the old code was
taking advantage of the l1_bits variable, we're going to get rid of
the other uses of l1_bits in a later patch anyway, so it doesn't make
sense to keep it just for this.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: a5f626fed526b7459a0425fad06d823d18df8522.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_get_table_addr(). This is no longer necessary so this
parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: eb0ed90affcf302e5a954bafb5931b5215483d3a.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_get_table_idx() and qcow2_cache_table_release(). This
is no longer necessary so this parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 9724f7e38e763ad3be32627c6b7fe8df9edb1476.1517840877.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_table_release(). This is no longer necessary so this
parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: b74f17591af52f201de0ea3a3b2dd0a81932334d.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was never using the BlockDriverState parameter so it can
be safely removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 49c74fe8b3aead9056e61a85b145ce787d06262b.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_get_table_idx(). This is no longer necessary so this
parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 6f98155489054a457563da77cdad1a66ebb3e896.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to pass it
to qcow2_cache_get_table_idx(). This is no longer necessary so this
parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 5c40516a91782b083c1428b7b6a41bb9e2679bfb.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to get the
cache table size (since it was equal to the cluster size). This is no
longer necessary so this parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 7c1b262344375d52544525f85bbbf0548d5ba575.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to get the
cache table size (since it was equal to the cluster size). This is no
longer necessary so this parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: da3575d47c9a181a2cfd4715e53dd84a2c651017.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function was only using the BlockDriverState parameter to get the
cache table size (since it was equal to the cluster size). This is no
longer necessary so this parameter can be removed.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: e1f943a9e89e1deb876f45de1bb22419ccdb6ad3.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The table size in the qcow2 cache is currently equal to the cluster
size. This doesn't allow us to use the cache memory efficiently,
particularly with large cluster sizes, so we need to be able to have
smaller cache tables that are independent from the cluster size. This
patch adds a new field to Qcow2Cache that we can use instead of the
cluster size.
The current table size is still being initialized to the cluster size,
so there are no semantic changes yet, but this patch will allow us to
prepare the rest of the code and simplify a few function calls.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 67a1bf9e55f417005c567bead95a018dc34bc687.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
This function has not been returning the offset of the L2 table since
commit 3948d1d487
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: b498733b6706a859a03678d74ecbd26aeba129aa.1517840876.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
To maintain load/store disabled bitmap there is new approach:
- deprecate @autoload flag of block-dirty-bitmap-add, make it ignored
- store enabled bitmaps as "auto" to qcow2
- store disabled bitmaps without "auto" flag to qcow2
- on qcow2 open load "auto" bitmaps as enabled and others
as disabled (except in_use bitmaps)
Also, adjust iotests 165 and 176 appropriately.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180202160752.143796-1-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
sd_prealloc() will now preallocate the area [old_size, new_size). As
before, it rounds to buf_size and may thus overshoot and preallocate
areas that were not requested to be preallocated. For image creation,
this is no change in behavior. For truncation, this is in accordance
with the documentation for preallocated truncation.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We want to use this function in sd_truncate() later on, so taking a
filename is not exactly ideal.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
By using qemu_do_cluster_truncate() in qemu_cluster_truncate(), we now
automatically have preallocated truncation.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of expecting the current size to be 0, query it and allocate
only the area [current_size, offset) if preallocation is requested.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Pull out the truncation code from the qemu_cluster_create() function so
we can later reuse it in qemu_gluster_truncate().
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
glfs_close() is a classical clean-up operation, as can be seen by the
fact that it is executed even if the truncation before it failed.
Also, moving it to clean-up makes it more clear that if it fails, we do
not want it to overwrite the current ret value if that signifies an
error already.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
g_realloc() aborts the program if it fails to allocate the required
amount of memory. We want to detect that scenario and return an error
instead, so let's use g_try_realloc().
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We don't need the can_write_zeroes_with_unmap field in
BlockDriverInfo, because it is redundant information with
supported_zero_flags & BDRV_REQ_MAY_UNMAP. Note that
BlockDriverInfo and supported_zero_flags are both per-device
settings, rather than global state about the driver as a
whole, which means one or both of these bits of information
can already be conditional. Let's audit how they were set:
crypto: always setting can_write_ to false is pointless (the
struct starts life zero-initialized), no use of supported_
nbd: just recently fixed to set can_write_ if supported_
includes MAY_UNMAP (thus this commit effectively reverts
bca80059e and solves the problem mentioned there in a more
global way)
file-posix, iscsi, qcow2: can_write_ is conditional, while
supported_ was unconditional; but passing MAY_UNMAP would
fail with ENOTSUP if the condition wasn't met
qed: can_write_ is unconditional, but pwrite_zeroes lacks
support for MAY_UNMAP and supported_ is not set. Perhaps
support can be added later (since it would be similar to
qcow2), but for now claiming false is no real loss
all other drivers: can_write_ is not set, and supported_ is
either unset or a passthrough
Simplify the code by moving the conditional into
supported_zero_flags for all drivers, then dropping the
now-unused BDI field. For callers that relied on
bdrv_can_write_zeroes_with_unmap(), we return the same
per-device settings for drivers that had conditions (no
observable change in behavior there); and can now return
true (instead of false) for drivers that support passthrough
(for example, the commit driver) which gives those drivers
the same fix as nbd just got in bca80059e. For callers that
relied on supported_zero_flags, we now have a few more places
that can avoid a wasted call to pwrite_zeroes() that will
just fail with ENOTSUP.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180126193439.20219-1-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
qemu-common.h includes qemu/option.h, but most places that include the
former don't actually need the latter. Drop the include, and add it
to the places that actually need it.
While there, drop superfluous includes of both headers, and
separate #include from file comment with a blank line.
This cleanup makes the number of objects depending on qemu/option.h
drop from 4545 (out of 4743) to 284 in my "build everything" tree.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-20-armbru@redhat.com>
[Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-19-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-15-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/qmp/qdict.h
drop from 4550 (out of 4743) to 368 in my "build everything" tree.
For qapi/qmp/qobject.h, the number drops from 4552 to 390.
While there, separate #include from file comment with a blank line.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-13-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/qmp/qlist.h
drop from 4551 (out of 4743) to 16 in my "build everything" tree.
While there, separate #include from file comment with a blank line.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-12-armbru@redhat.com>
The macro expansions of qdict_put_TYPE() and qlist_append_TYPE() need
qbool.h, qnull.h, qnum.h and qstring.h to compile. We include qnull.h
and qnum.h in the headers, but not qbool.h and qstring.h. Works,
because we include those wherever the macros get used.
Open-coding these helpers is of dubious value. Turn them into
functions and drop the includes from the headers.
This cleanup makes the number of objects depending on qapi/qmp/qnum.h
from 4551 (out of 4743) to 46 in my "build everything" tree. For
qapi/qmp/qnull.h, the number drops from 4552 to 21.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-10-armbru@redhat.com>
qapi/qmp/types.h is a convenience header to include a number of
qapi/qmp/ headers. Since we rarely need all of the headers
qapi/qmp/types.h includes, we bypass it most of the time. Most of the
places that use it don't need all the headers, either.
Include the necessary headers directly, and drop qapi/qmp/types.h.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-9-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-6-armbru@redhat.com>
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.
While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
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, with the change
to target/s390x/gen-features.c manually reverted, and blank lines
around deletions collapsed.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-3-armbru@redhat.com>
Forward these two calls to the IOVA manager.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20180116060901.17413-6-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Allow block driver to map and unmap a buffer for later I/O, as a performance
hint.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20180116060901.17413-5-famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
This is a new protocol driver that exclusively opens a host NVMe
controller through VFIO. It achieves better latency than linux-aio by
completely bypassing host kernel vfs/block layer.
$rw-$bs-$iodepth linux-aio nvme://
----------------------------------------
randread-4k-1 10.5k 21.6k
randread-512k-1 745 1591
randwrite-4k-1 30.7k 37.0k
randwrite-512k-1 1945 1980
(unit: IOPS)
The driver also integrates with the polling mechanism of iothread.
This patch is co-authored by Paolo and me.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20180116060901.17413-4-famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Now that CoQueues can use a QemuMutex for thread-safety, there is no
need for curl to roll its own coroutine queue. Coroutines can be
placed directly on the queue instead of using a list of CURLAIOCBs.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20180203153935.8056-6-pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
This patch prevents a possible segmentation fault when .desc members are checked
against NULL.
The ssh_runtime_opts was added by commit
8a6a80896d ("block/ssh: Use QemuOpts for runtime
options").
This fix was inspired by
http://lists.nongnu.org/archive/html/qemu-devel/2018-01/msg00883.html.
Fixes: 8a6a80896d ("block/ssh: Use QemuOpts for runtime options")
Cc: Max Reitz <mreitz@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Since mirror job supports efficient zero out target mechanism (see
in mirror_dirty_init()), implement bdrv_get_info to make it work
over NBD. Such improvement will allow using the largest chunk possible
and will decrease the number of NBD_CMD_WRITE_ZEROES requests on the wire.
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Message-Id: <20180118115158.17219-1-edgar.kaziakhmedov@virtuozzo.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
# gpg: Signature made Tue 23 Jan 2018 12:38:36 GMT
# gpg: using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (29 commits)
iotests: Disable some tests for compat=0.10
iotests: Split 177 into two parts for compat=0.10
iotests: Make 059 pass on machines with little RAM
iotests: Filter compat-dependent info in 198
iotests: Make 191 work with qcow2 options
iotests: Make 184 image-less
iotests: Make 089 compatible with compat=0.10
iotests: Fix 067 for compat=0.10
iotests: Fix 059's reference output
iotests: Fix 051 for compat=0.10
iotests: Fix 020 for vmdk
iotests: Skip 103 for refcount_bits=1
iotests: Forbid 020 for non-file protocols
iotests: Drop format-specific in _filter_img_info
iotests: Fix _img_info for backslashes
block/vmdk: Add blkdebug events
block/qcow: Add blkdebug events
qcow2: No persistent dirty bitmaps for compat=0.10
block/vmdk: Fix , instead of ; at end of line
qemu-iotests: Fix locking issue in 102
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is certainly not complete, but it includes at least write_aio and
read_aio.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171123020832.8165-5-mreitz@redhat.com
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
This is not necessarily complete, but it should include the most
important places.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171123020832.8165-4-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Persistent dirty bitmaps require a properly functioning
autoclear_features field, or we cannot track when an unsupporting
program might overwrite them. Therefore, we cannot support them for
compat=0.10 images.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171123020832.8165-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We can easily repair unaligned preallocated zero clusters by discarding
them, so why not do it?
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203759.14018-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Since parallels format supports backing files, refine
readv/writev (allocate_clusters) to redirect read/write requests
to a backing file (if cluster is not available in the current bs).
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com>
Message-id: 20180112090122.1702-6-klim.kireev@virtuozzo.com
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
To implement xml format, some defines and structures
from parallels.c are required.
Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Message-id: 20180112090122.1702-4-klim.kireev@virtuozzo.com
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This dependency is required for adequate Parallels images support.
Typically the disk consists of several images which are glued by
XML disk descriptor. Also XML hides inside several important parameters
which are not available in the image header.
The patch also adds clause to checkpatch.pl to understand libxml2 types.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Klim Kireev <klim.kireev@virtuozzo.com>
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20180112090122.1702-3-klim.kireev@virtuozzo.com
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
in case of unaligned requests or on a target that does not support
block provisioning we leave iTask uninitialized and check iTask.task
for NULL later.
Fixes: e38bc23454
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1515425247-21730-1-git-send-email-pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The find_desc_by_name() from util/qemu-option.c relies on the .name not being
NULL to call strcmp(). This check becomes unsafe when the list is not
NULL-terminated, which is the case of nbd_runtime_opts in block/nbd.c, and can
result in segmentation fault when strcmp() tries to access an invalid memory:
#0 0x00007fff8c75f7d4 in __strcmp_power9 () from /lib64/libc.so.6
#1 0x00000000102d3ec8 in find_desc_by_name (desc=0x1036d6f0, name=0x28e46670 "server.path") at util/qemu-option.c:166
#2 0x00000000102d93e0 in qemu_opts_absorb_qdict (opts=0x28e47a80, qdict=0x28e469a0, errp=0x7fffec247c98) at util/qemu-option.c:1026
#3 0x000000001012a2e4 in nbd_open (bs=0x28e42290, options=0x28e469a0, flags=24578, errp=0x7fffec247d80) at block/nbd.c:406
#4 0x00000000100144e8 in bdrv_open_driver (bs=0x28e42290, drv=0x1036e070 <bdrv_nbd_unix>, node_name=0x0, options=0x28e469a0, open_flags=24578, errp=0x7fffec247f50) at block.c:1135
#5 0x0000000010015b04 in bdrv_open_common (bs=0x28e42290, file=0x0, options=0x28e469a0, errp=0x7fffec247f50) at block.c:1395
>From gdb, the desc[i].name was not NULL and resulted in strcmp() accessing an
invalid memory:
>>> p desc[5]
$8 = {
name = 0x1037f098 "R27A",
type = 1561964883,
help = 0xc0bbb23e <error: Cannot access memory at address 0xc0bbb23e>,
def_value_str = 0x2 <error: Cannot access memory at address 0x2>
}
>>> p desc[6]
$9 = {
name = 0x103dac78 <__gcov0.do_qemu_init_bdrv_nbd_init> "\001",
type = 272101528,
help = 0x29ec0b754403e31f <error: Cannot access memory at address 0x29ec0b754403e31f>,
def_value_str = 0x81f343b9 <error: Cannot access memory at address 0x81f343b9>
}
This patch fixes the segmentation fault in strcmp() by adding a NULL element at
the end of nbd_runtime_opts.desc list, which is the common practice to most of
other structs like runtime_opts in block/null.c. Thus, the desc[i].name != NULL
check becomes safe because it will not evaluate to true when .desc list reached
its end.
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1727259
Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.vnet.ibm.com>
Message-Id: <20180105133241.14141-2-muriloo@linux.vnet.ibm.com>
CC: qemu-stable@nongnu.org
Fixes: 7ccc44fd7d
Signed-off-by: Eric Blake <eblake@redhat.com>
The bdrv_reopen*() implementation doesn't like it if the graph is
changed between queuing nodes for reopen and actually reopening them
(one of the reasons is that queuing can be recursive).
So instead of draining the device only in bdrv_reopen_multiple(),
require that callers already drained all affected nodes, and assert this
in bdrv_reopen_queue().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Since commit bde70715, base is the only node that is reopened in
commit_start(). This means that the code, which still involves an
explicit BlockReopenQueue, can now be simplified by using bdrv_reopen().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
We need to remember how many of the drain sections in which a node is
were recursive (i.e. subtree drain rather than node drain), so that they
can be correctly applied when children are added or removed during the
drained section.
With this change, it is safe to modify the graph even inside a
bdrv_subtree_drained_begin/end() section.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_drained_begin() waits for the completion of requests in the whole
subtree, but it only actually keeps its immediate bs parameter quiesced
until bdrv_drained_end().
Add a version that keeps the whole subtree drained. As of this commit,
graph changes cannot be allowed during a subtree drained section, but
this will be fixed soon.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is in preparation for subtree drains, i.e. drained sections that
affect not only a single node, but recursively all child nodes, too.
Calling the parent callbacks for drain is pointless when we just came
from that parent node recursively and leads to multiple increases of
bs->quiesce_counter in a single drain call. Don't do it.
In order for this to work correctly, the parent callback must be called
for every bdrv_drain_begin/end() call, not only for the outermost one:
If we have a node N with two parents A and B, recursive draining of A
should cause the quiesce_counter of B to increase because its child N is
drained independently of B. If now B is recursively drained, too, A must
increase its quiesce_counter because N is drained independently of A
only now, even if N is going from quiesce_counter 1 to 2.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_do_drained_begin() restricts the call of parent callbacks and
aio_disable_external() to the outermost drain section, but the block
driver callbacks are always called. bdrv_do_drained_end() must match
this behaviour, otherwise nodes stay drained even if begin/end calls
were balanced.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Block jobs are already paused using the BdrvChildRole drain callbacks,
so we don't need an additional block_job_pause_all() call.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_drained_begin() doesn't increase bs->quiesce_counter recursively
and also doesn't notify other parent nodes of children, which both means
that the child nodes are not actually drained, and bdrv_drained_begin()
is providing useful functionality only on a single node.
To keep things consistent, we also shouldn't call the block driver
callbacks recursively.
A proper recursive drain version that provides an actually working
drained section for child nodes will be introduced later.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Since bdrv_co_preadv does all neccessary checks including
reading after the end of the backing file, avoid duplication
of verification before bdrv_co_preadv call.
Signed-off-by: Edgar Kaziakhmedov <edgar.kaziakhmedov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Drain requests are propagated to child nodes, parent nodes and directly
to the AioContext. The order in which this happened was different
between all combinations of drain/drain_all and begin/end.
The correct order is to keep children only drained when their parents
are also drained. This means that at the start of a drained section, the
AioContext needs to be drained first, the parents second and only then
the children. The correct order for the end of a drained section is the
opposite.
This patch changes the three other functions to follow the example of
bdrv_drained_begin(), which is the only one that got it right.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
The device is drained, so there is no point in waiting for requests at
the end of the drained section. Remove the bdrv_drain_recurse() calls
there.
The bdrv_drain_recurse() calls were introduced in commit 481cad48e5
in order to call the .bdrv_co_drain_end() driver callback. This is now
done by a separate bdrv_drain_invoke() call.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Now that the bdrv_drain_invoke() calls are pulled up to the callers of
bdrv_drain_recurse(), the 'begin' parameter isn't needed any more.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
bdrv_drain_all_begin() used to call the .bdrv_co_drain_begin() driver
callback inside its polling loop. This means that how many times it got
called for each node depended on long it had to poll the event loop.
This is obviously not right and results in nodes that stay drained even
after bdrv_drain_all_end(), which calls .bdrv_co_drain_begin() once per
node.
Fix bdrv_drain_all_begin() to call the callback only once, too.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
This change separates bdrv_drain_invoke(), which calls the BlockDriver
drain callbacks, from bdrv_drain_recurse(). Instead, the function
performs its own recursion now.
One reason for this is that bdrv_drain_recurse() can be called multiple
times by bdrv_drain_all_begin(), but the callbacks may only be called
once. The separation is necessary to fix this bug.
The other reason is that we intend to go to a model where we call all
driver callbacks first, and only then start polling. This is not fully
achieved yet with this patch, as bdrv_drain_invoke() contains a
BDRV_POLL_WHILE() loop for the block driver callbacks, which can still
call callbacks for any unrelated event. It's a step in this direction
anyway.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
we currently report an "iSCSI Failure" in iscsi_co_generic_cb if the task
hasn't completed with SCSI_STATUS_GOOD. However, we expect a failure in
some cases and handle it gracefully. This is the case for misaligned UNMAPs
and WRITESAME10/16 calls without UNMAP. In this case a failure in the
logs can be quite misleading.
While we are at it improve the logging to reveal which operation failed
at what LBA.
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1512733868-9009-3-git-send-email-pl@kamp.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
we forgot to set the allocmap to invalid if an UNMAP call fails.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-Id: <1512733868-9009-2-git-send-email-pl@kamp.de>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The AioContext pointer argument to co_aio_sleep_ns() is only used for
the sleep timer. It does not affect where the caller coroutine is
resumed.
Due to changes to coroutine and AIO APIs it is now possible to drop the
AioContext pointer argument. This is safe to do since no caller has
specific requirements for which AioContext the timer must run in.
This patch drops the AioContext pointer argument and renames the
function to simplify the API.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Reported-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20171109102652.6360-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If curl_global_init() fails, per the documentation no other curl
functions may be called, so make sure to check the return value.
Also, some minor changes to the initialization latch variable 'inited':
- Make it static in the file, for clarity
- Change the name for clarity
- Make it a bool
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
No functional changes, just whitespace manipulation.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
'tag' is already checked in the lines immediately preceding this check,
and set to non-NULL if NULL. No need to check again, it hasn't changed.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>
We can use copy_bitmap instead of sync_bitmap. copy_bitmap is
initialized from sync_bitmap and it is more informative: we will not try
to process data, that is already in progress (by write notifier).
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20171012135313.227864-6-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Set fake progress for non-dirty clusters in copy_bitmap initialization,
to. It simplifies code and allows further refactoring.
This patch changes user's view of backup progress, but formally it
doesn't changed: progress hops are just moved to the beginning.
Actually it's just a point of view: when do we actually skip clusters?
We can say in the very beginning, that we skip these clusters and do
not think about them later.
Of course, if go through disk sequentially, it's logical to say, that
we skip clusters between copied portions to the left and to the right
of them. But even now copying progress is not sequential because of
write notifiers. Future patches will introduce new backup architecture
which will do copying in several coroutines in parallel, so it will
make no sense to publish fake progress by parts in parallel with
other copying requests.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20171012135313.227864-5-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
We should not copy non-dirty clusters in write notifiers. So,
initialize copy_bitmap from sync_bitmap.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171012135313.227864-4-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
Use HBitmap copy_bitmap instead of done_bitmap. This is needed to
improve incremental backup in following patches and to unify backup
loop for full/incremental modes in future patches.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20171012135313.227864-3-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
The function searches for next zero bit.
Also add interface for BdrvDirtyBitmap and unit test.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20171012135313.227864-2-vsementsov@virtuozzo.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
applied using ./scripts/clean-includes
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE) was overflowing ret (int) if
st.st_size is greater than 1TB.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Lieven <pl@kamp.de>
Message-id: 1511798407-31129-1-git-send-email-pl@kamp.de
Signed-off-by: Max Reitz <mreitz@redhat.com>
All callers are using QEMU_CLOCK_REALTIME, and it will not be possible to
support more than one clock when block_job_sleep_ns switches to a single
timer stored in the BlockJob struct.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Tested-By: Jeff Cody <jcody@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The .drained_begin/end callbacks can (directly or indirectly via
aio_poll()) cause block nodes to be removed or the current BdrvChild to
point to a different child node.
Use QLIST_FOREACH_SAFE() to make sure we don't access invalid
BlockDriverStates or accidentally continue iterating the parents of the
new child node instead of the node we actually came from.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Loading a snapshot invalidates the bitmap. Just marking all blocks dirty
is not a useful response in practice, instead the user needs to be aware
that we switch to a completely different state. If they are okay with
losing the dirty bitmap, they can just explicitly delete it.
This effectively reverts commit 04dec3c3ae.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
'qemu-img info' makes sense even when BLK_PERM_CONSISTENT_READ cannot be
granted because of a block job in a running qemu process. It already
sets BDRV_O_NO_IO to indicate that it doesn't access the guest visible
data at all.
Check the BDRV_O_NO_IO flags in blk_new_open(), so that I/O related
permissions are not unnecessarily requested and 'qemu-img info' can work
even if BLK_PERM_CONSISTENT_READ cannot be granted.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
On one hand, it is a good idea for bdrv_next() to return a strong
reference because ideally nearly every pointer should be refcounted.
This fixes intermittent failure of iotest 194.
On the other, it is absolutely necessary for bdrv_next() itself to keep
a strong reference to both the BB (in its first phase) and the BDS (at
least in the second phase) because when called the next time, it will
dereference those objects to get a link to the next one. Therefore, it
needs these objects to stay around until then. Just storing the pointer
to the next in the iterator is not really viable because that pointer
might become invalid as well.
Both arguments taken together means we should probably just invoke
bdrv_ref() and blk_ref() in bdrv_next(). This means we have to assert
that bdrv_next() is always called from the main loop, but that was
probably necessary already before this patch and judging from the
callers, it also looks to actually be the case.
Keeping these strong references means however that callers need to give
them up if they decide to abort the iteration early. They can do so
through the new bdrv_next_cleanup() function.
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110172545.32609-1-mreitz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
@mem_size and @offset are both size_t, thus subtracting them from one
another will just return a big size_t if mem_size < offset -- even more
obvious here because the result is stored in another size_t.
Checking that result to be positive is therefore not sufficient to
exclude the case that offset > mem_size. Thus, we currently sometimes
issue an madvise() over a very large address range.
This is triggered by iotest 163, but with -m64, this does not result in
tangible problems. But with -m32, this test produces three segfaults,
all of which are fixed by this patch.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171114184127.24238-1-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Instead of using an assertion, it is better to emit a corruption event
here. Checking all offsets for correct alignment can be tedious and it
is easily possible to forget to do so. qcow2_cache_do_get() is a
function every L2 and refblock access has to go through, so this is a
good central point to add such a check.
And for good measure, let us also add an assertion that the offset is
non-zero. Making this a corruption event is not feasible, because a
zero offset usually means something special (such as the cluster is
unused), so all callers should be checking this anyway. If they do not,
it is their fault, hence the assertion here.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-6-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728661
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-5-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We currently do not guard everywhere against a NULL bs->drv where we
should be doing so. Most of the places fixed here just do not care
about that case at all.
Some care implicitly, e.g. through a prior function call to
bdrv_getlength() which would always fail for an ejected BDS. Add an
assert there to make it more obvious.
Other places seem to care, but do so insufficiently: Freeing clusters in
a qcow2 image is an error-free operation, but it may leave the image in
an unusable state anyway. Giving qcow2_free_clusters() an error code is
not really viable, it is much easier to note that bs->drv may be NULL
even after a successful driver call. This concerns bdrv_co_flush(), and
the way the check is added to bdrv_co_pdiscard() (in every iteration
instead of only once).
Finally, some places employ at least an assert(bs->drv); somewhere, that
may be reasonable (such as in the reopen code), but in
bdrv_has_zero_init(), it is definitely not. Returning 0 there in case
of an ejected BDS saves us much headache instead.
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728660
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-4-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We should check whether the cluster offset we are about to use is
actually valid; that is, whether it is aligned to cluster boundaries.
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728643
Buglink: https://bugs.launchpad.net/qemu/+bug/1728657
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-3-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
When trying to repair a dirty image, qcow2_check() may apparently
succeed (no really fatal error occurred that would prevent the check
from continuing), but if check_errors in the result object is non-zero,
we cannot trust the image to be usable.
Reported-by: R. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728639
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-2-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Misaligned compressed write is not supported.
Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-id: 1510654613-47868-2-git-send-email-anton.nefedov@virtuozzo.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If an image contains persistent bitmaps, we cannot use the
fast path of bdrv_make_empty() to clear the image during
qemu-img commit, because that will lose the clusters related
to the bitmaps.
Also leave a comment in qcow2_read_extensions to remind future
feature additions to think about fast-path removal, since we
just barely fixed the same bug for LUKS encryption.
It's a pain that qemu-img has not yet been taught to manipulate,
or even at a very minimum display, information about persistent
bitmaps; instead, we have to use QMP commands. It's also a
pain that only qeury-block and x-debug-block-dirty-bitmap-sha256
will allow bitmap introspection; but the former requires the
node to be hooked to a block device, and the latter is experimental.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If a server fails a read, for example with EIO, but the connection
is still live, then we would crash trying to print a non-existent
error message in nbd_client_co_preadv(). For consistency, also
change the error printout in nbd_read_reply_entry(), although that
instance does not crash. Bug introduced in commit f140e300.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171112013936.5942-1-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
After committing the qcow2 image contents into the base image, qemu-img
will call bdrv_make_empty to drop the payload in the layered image.
When this is done for qcow2 images, it blows away the LUKS encryption
header, making the resulting image unusable. There are two codepaths
for emptying a qcow2 image, and the second (slower) codepath leaves
the LUKS header intact, so force use of that codepath.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_set_read_only() is used by some block drivers to override the
read-only option given by the user. This is not how read-only images
generally work in QEMU: Instead of second guessing what the user really
meant (which currently includes making an image read-only even if the
user didn't only use the default, but explicitly said read-only=off), we
should error out if we can't provide what the user requested.
This adds deprecation warnings to all callers of bdrv_set_read_only() so
that the behaviour can be corrected after the usual deprecation period.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently if trying to change encryption parameters on a qcow2 image, qemu-img
will abort. We already explicitly check for attempt to change encrypt.format
but missed other parameters like encrypt.key-secret. Rather than list each
parameter, just blacklist changing of all parameters with a 'encrypt.' prefix.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
replication_child_perm request write
permissions for all child which will lead bdrv_check_perm fail.
replication_child_perm() should request write
permissions only if it is writable itself.
Signed-off-by: Wang Guang <wang.guang55@zte.com.cn>
Signed-off-by: Wang Yong <wang.yong155@zte.com.cn>
Reviewed-by: Xie Changlong <xiechanglong@cmss.chinamobile.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
tg->any_timer_armed[] must be cleared when detaching pending timers from
the AioContext. Failure to do so leads to hung I/O because it looks
like there are still timers pending when in fact they have been removed.
Other ThrottleGroupMembers might have requests pending too so it's
necessary to schedule the next TGM so it can set a timer.
This patch fixes hung I/O when QEMU is launched with drives that are in
the same throttling group:
(guest)$ dd if=/dev/zero of=/dev/vdb oflag=direct bs=512 &
(guest)$ dd if=/dev/zero of=/dev/vdc oflag=direct bs=512 &
(qemu) stop
(qemu) cont
...I/O is stuck...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171116112150.27607-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Migration does not work for parallels, and has been broken for a while
(see patch 'block/parallels: Do not update header or truncate image when
INMIGRATE'). The bdrv_invalidate_cache() method needs to be added for
migration to be supported. Until this is done, prohibit migration.
Signed-off-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 5e04a7c8a3089913fa58d484af42dab7993984ad.1510059970.git.jcody@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If we write or modify the image file while the QEMU run state is
INMIGRATE, then the BDRV_O_INACTIVE BDS flag is set. This will cause
an assert, since the image is marked inactive. Make sure we obey this
flag.
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 3996c930fa8cde8570b7a63032720d76a28fd78b.1510059970.git.jcody@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The VHDX specification requires that before user data modification of
the vhdx image, the VHDX header file and data GUIDs need to be updated.
In vhdx_open(), if the image is set to RDWR, we go ahead and update the
header.
However, just because the image is set to RDWR does not mean we can go
ahead and write at this point - specifically, if the QEMU run state is
INMIGRATE, the underlying file BS may be set to inactive via the BDS
open flag of BDRV_O_INACTIVE. Attempting to write under this condition
will cause an assert in bdrv_co_pwritev().
We can alternatively latch the first time the image is written. And lo
and behold, we do just that, via vhdx_user_visible_write() in
vhdx_co_writev(). This means the call to vhdx_update_headers() in
vhdx_open() is likely just vestigial, and can be removed.
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Jeff Cody <jcody@redhat.com>
Message-id: 659e4cdba6ef4c651737852777c8c93d27b38040.1510059970.git.jcody@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Snapshot-switch actually changes active state of disk so it should
reflect on dirty bitmaps. Otherwise next incremental backup using
these bitmaps will be invalid.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20171023092945.54532-1-vsementsov@virtuozzo.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The crypto header is initialized only when QEMU is creating a new
image, so there's no chance of this happening on a corrupted image.
If QEMU is really trying to allocate the header overlapping other
existing metadata sections then this is a serious bug in QEMU itself
so let's add an assertion.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: ae3d77f312fc0c5e0ac2bbd71676c0112eebe2e5.1509718618.git.berto@igalia.com
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
qcow2_do_open() is checking that header.refcount_table_clusters is not
too large, but it doesn't check that it's greater than zero. Apart
from the fact that an image like that is obviously corrupted, trying
to use it crashes QEMU since we end up with a null s->refcount_table
after qcow2_refcount_init().
These images can however be repaired, so allow opening them if the
BDRV_O_CHECK flag is set.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: f9750f50c80359babba11062e88f5075a47e8e16.1509718618.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
If the refcount data is corrupted then we can end up trying to
allocate a new compressed cluster at offset 0 in the image, triggering
an assertion in qcow2_alloc_bytes() that would crash QEMU:
qcow2_alloc_bytes: Assertion `offset' failed.
This patch adds an explicit check for this scenario and a new test
case.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: fb53467cf48e95ff3330def1cf1003a5b862b7d9.1509718618.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
If the refcount data is corrupted then we can end up trying to
allocate a new L2 table at offset 0 in the image, triggering an
assertion in the qcow2 cache that would crash QEMU:
qcow2_cache_entry_mark_dirty: Assertion `c->entries[i].offset != 0' failed
This patch adds an explicit check for this scenario and a new test
case.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 92dac37191ae7844a2da22c122204eb493cc3133.1509718618.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
Each entry in the qcow2 cache contains an offset field indicating the
location of the data in the qcow2 image. If the offset is 0 then it
means that the entry contains no data and is available to be used when
needed.
Because of that it is not possible to store in the cache the first
cluster of the qcow2 image (offset = 0). This is not a problem because
that cluster always contains the qcow2 header and we're not using this
cache for that.
However, if the qcow2 image is corrupted it can happen that we try to
allocate a new refcount block at offset 0, triggering this assertion
and crashing QEMU:
qcow2_cache_entry_mark_dirty: Assertion `c->entries[i].offset != 0' failed
This patch adds an explicit check for this scenario and a new test
case.
This problem was originally reported here:
https://bugs.launchpad.net/qemu/+bug/1728615
Reported-by: R.Nageswara Sastry <nasastry@in.ibm.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 92a2fadd10d58b423f269c1d1a309af161cdc73f.1509718618.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
The following disk I/O throttling fixes solve recent bugs.
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Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging
Pull request
The following disk I/O throttling fixes solve recent bugs.
# gpg: Signature made Tue 14 Nov 2017 10:37:12 GMT
# gpg: using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35 775A 9CA4 ABB3 81AB 73C8
* remotes/stefanha/tags/block-pull-request:
qemu-iotests: Test I/O limits with removable media
block: Leave valid throttle timers when removing a BDS from a backend
block: Check for inserted BlockDriverState in blk_io_limits_disable()
throttle-groups: drain before detaching ThrottleState
block: all I/O should be completed before removing throttle timers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
If a BlockBackend has I/O limits set then its ThrottleGroupMember
structure uses the AioContext from its attached BlockDriverState.
Those two contexts must be kept in sync manually. This is not
ideal and will be fixed in the future by removing the throttling
configuration from the BlockBackend and storing it in an implicit
filter node instead, but for now we have to live with this.
When you remove the BlockDriverState from the backend then the
throttle timers are destroyed. If a new BlockDriverState is later
inserted then they are created again using the new AioContext.
There are a couple of problems with this:
a) The code manipulates the timers directly, leaving the
ThrottleGroupMember.aio_context field in an inconsisent state.
b) If you remove the I/O limits (e.g by destroying the backend)
when the timers are gone then throttle_group_unregister_tgm()
will attempt to destroy them again, crashing QEMU.
While b) could be fixed easily by allowing the timers to be freed
twice, this would result in a situation in which we can no longer
guarantee that a valid ThrottleState has a valid AioContext and
timers.
This patch ensures that the timers and AioContext are always valid
when I/O limits are set, regardless of whether the BlockBackend has a
BlockDriverState inserted or not.
[Fixed "There'a" typo as suggested by Max Reitz <mreitz@redhat.com>
--Stefan]
Reported-by: sochin jiang <sochin.jiang@huawei.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: e089c66e7c20289b046d782cea4373b765c5bc1d.1510339534.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When you set I/O limits using block_set_io_throttle or the command
line throttling.* options they are kept in the BlockBackend regardless
of whether a BlockDriverState is attached to the backend or not.
Therefore when removing the limits using blk_io_limits_disable() we
need to check if there's a BDS before attempting to drain it, else it
will crash QEMU. This can be reproduced very easily using HMP:
(qemu) drive_add 0 if=none,throttling.iops-total=5000
(qemu) drive_del none0
Reported-by: sochin jiang <sochin.jiang@huawei.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 0d3a67ce8d948bb33e08672564714dcfb76a3d8c.1510339534.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
I/O requests hang after stop/cont commands at least since QEMU 2.10.0
with -drive iops=100:
(guest)$ dd if=/dev/zero of=/dev/vdb oflag=direct count=1000
(qemu) stop
(qemu) cont
...I/O is stuck...
This happens because blk_set_aio_context() detaches the ThrottleState
while requests may still be in flight:
if (tgm->throttle_state) {
throttle_group_detach_aio_context(tgm);
throttle_group_attach_aio_context(tgm, new_context);
}
This patch encloses the detach/attach calls in a drained region so no
I/O request is left hanging. Also add assertions so we don't make the
same mistake again in the future.
Reported-by: Yongxue Hong <yhong@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 20171110151934.16883-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
In blk_remove_bs, all I/O should be completed before removing throttle
timers. If there has inflight I/O, removing throttle timers here will
cause the inflight I/O never return.
This patch add bdrv_drained_begin before throttle_timers_detach_aio_context
to let all I/O completed before removing throttle timers.
[Moved declaration of bs as suggested by Alberto Garcia
<berto@igalia.com>.
--Stefan]
Signed-off-by: Zhengui <lizhengui@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1508564040-120700-1-git-send-email-lizhengui@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Ensure that the server is not sending unexpected chunk lengths
for either the NONE or the OFFSET_DATA chunk, nor unexpected
hole length for OFFSET_HOLE. This will flag any server as
broken that responds to a zero-length read with an OFFSET_DATA
(what our server currently does, but that's about to be fixed)
or with OFFSET_HOLE, even though we previously fixed our client
to never be able to send such a request over the wire.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171108215703.9295-7-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
The NBD spec was recently clarified to state that clients should
not send 0-length requests to the server, as the server behavior
is undefined [1]. We know that qemu-nbd's behavior is a successful
no-op (once it has filtered for read-only exports), but other NBD
implementations might return an error. To avoid any questionable
server implementations, it is better to just short-circuit such
requests on the client side (we are relying on the block layer to
already filter out requests such as invalid offset, write to a
read-only volume, and so forth); do the short-circuit as late as
possible to still benefit from protections from assertions that
the block layer is not violating our assumptions.
[1] https://github.com/NetworkBlockDevice/nbd/commit/ee926037
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171108215703.9295-6-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
The NBD spec says that clients should not try to write/trim to
an export advertised as read-only by the server. But we failed
to check that, and would allow the block layer to use NBD with
BDRV_O_RDWR even when the server is read-only, which meant we
were depending on the server sending a proper EPERM failure for
various commands, and also exposes a leaky abstraction: using
qemu-io in read-write mode would succeed on 'w -z 0 0' because
of local short-circuiting logic, but 'w 0 0' would send a
request over the wire (where it then depends on the server, and
fails at least for qemu-nbd but might pass for other NBD
implementations).
With this patch, a client MUST request read-only mode to access
a server that is doing a read-only export, or else it will get
a message like:
can't open device nbd://localhost:10809/foo: request for write access conflicts with read-only export
It is no longer possible to even attempt writes over the wire
(including the corner case of 0-length writes), because the block
layer enforces the explicit read-only request; this matches the
behavior of qcow2 when backed by a read-only POSIX file.
Fix several iotests to comply with the new behavior (since
qemu-nbd of an internal snapshot, as well as nbd-server-add over QMP,
default to a read-only export, we must tell blockdev-add/qemu-io to
set up a read-only client).
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171108215703.9295-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Provide missing spaces that are required when using string
concatenation to break error messages across source lines.
Introduced in commit f140e300.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171108215703.9295-2-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Minimal implementation: for structured error only error_report error
message.
Note that test 83 is now more verbose, because the implementation
prints more warnings about unexpected communication errors; perhaps
future patches should tone things down by using trace messages
instead of traces, but the common case of successful communication
is no noisier than before.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171027104037.8319-13-eblake@redhat.com>
In following patch nbd_receive_reply will be used both for simple
and structured reply header receiving.
NBDReply is altered into union of simple reply header and structured
reply chunk header, simple error translation moved to block/nbd-client
to be consistent with further structured reply error translation.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171027104037.8319-11-eblake@redhat.com>
