Commit Graph

160 Commits

Author SHA1 Message Date
John Snow
111049a4ec blockjob: refactor backup_start as backup_job_create
Refactor backup_start as backup_job_create, which only creates the job,
but does not automatically start it. The old interface, 'backup_start',
is not kept in favor of limiting the number of nearly-identical interfaces
that would have to be edited to keep up with QAPI changes in the future.

Callers that wish to synchronously start the backup_block_job can
instead just call block_job_start immediately after calling
backup_job_create.

Transactions are updated to use the new interface, calling block_job_start
only during the .commit phase, which helps prevent race conditions where
jobs may finish before we even finish building the transaction. This may
happen, for instance, during empty block backup jobs.

Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1478587839-9834-6-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00
John Snow
5ccac6f186 blockjob: add block_job_start
Instead of automatically starting jobs at creation time via backup_start
et al, we'd like to return a job object pointer that can be started
manually at later point in time.

For now, add the block_job_start mechanism and start the jobs
automatically as we have been doing, with conversions job-by-job coming
in later patches.

Of note: cancellation of unstarted jobs will perform all the normal
cleanup as if the job had started, particularly abort and clean. The
only difference is that we will not emit any events, because the job
never actually started.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1478587839-9834-5-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00
John Snow
a7815a764c blockjob: add .start field
Add an explicit start field to specify the entrypoint. We already have
ownership of the coroutine itself AND managing the lifetime of the
coroutine, let's take control of creation of the coroutine, too.

This will allow us to delay creation of the actual coroutine until we
know we'll actually start a BlockJob in block_job_start. This avoids
the sticky question of how to "un-create" a Coroutine that hasn't been
started yet.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1478587839-9834-4-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00
John Snow
e8a40bf71d blockjob: add .clean property
Cleaning up after we have deferred to the main thread but before the
transaction has converged can be dangerous and result in deadlocks
if the job cleanup invokes any BH polling loops.

A job may attempt to begin cleaning up, but may induce another job to
enter its cleanup routine. The second job, part of our same transaction,
will block waiting for the first job to finish, so neither job may now
make progress.

To rectify this, allow jobs to register a cleanup operation that will
always run regardless of if the job was in a transaction or not, and
if the transaction job group completed successfully or not.

Move sensitive cleanup to this callback instead which is guaranteed to
be run only after the transaction has converged, which removes sensitive
timing constraints from said cleanup.

Furthermore, in future patches these cleanup operations will be performed
regardless of whether or not we actually started the job. Therefore,
cleanup callbacks should essentially confine themselves to undoing create
operations, e.g. setup actions taken in what is now backup_start.

Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1478587839-9834-3-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-14 22:47:34 -05:00
John Snow
c87621ea68 blockjobs: split interface into public/private, Part 1
To make it a little more obvious which functions are intended to be
public interface and which are intended to be for use only by jobs
themselves, split the interface into "public" and "private" files.

Convert blockjobs (e.g. block/backup) to using the private interface.
Leave blockdev and others on the public interface.

There are remaining uses of private state by qemu-img, and several
cases in blockdev.c and block/io.c where we grab job->blk for the
purposes of acquiring an AIOContext.

These will be corrected in future patches.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1477584421-1399-7-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-01 08:04:56 -04:00
John Snow
47970dfb0a Replication/Blockjobs: Create replication jobs as internal
Bubble up the internal interface to commit and backup jobs, then switch
replication tasks over to using this methodology.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1477584421-1399-4-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-01 07:55:57 -04:00
John Snow
f81e0b4532 blockjobs: Allow creating internal jobs
Add the ability to create jobs without an ID.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1477584421-1399-3-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-11-01 07:55:57 -04:00
Alberto Garcia
b7340d002e block: Use block_job_add_bdrv() in backup_start()
Use block_job_add_bdrv() instead of blocking all operations in
backup_start() and unblocking them in backup_run().

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-10-31 16:52:38 +01:00
Paolo Bonzini
bae8196d9f blockjob: introduce .drain callback for jobs
This is required to decouple block jobs from running in an
AioContext.  With multiqueue block devices, a BlockDriverState
does not really belong to a single AioContext.

The solution is to first wait until all I/O operations are
complete; then loop in the main thread for the block job to
complete entirely.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-Id: <1477565348-5458-3-git-send-email-pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
2016-10-28 21:50:18 +08:00
Fam Zheng
dc162c8e4f block: Hide HBitmap in block dirty bitmap interface
HBitmap is an implementation detail of block dirty bitmap that should be hidden
from users. Introduce a BdrvDirtyBitmapIter to encapsulate the underlying
HBitmapIter.

A small difference in the interface is, before, an HBitmapIter is initialized
in place, now the new BdrvDirtyBitmapIter must be dynamically allocated because
the structure definition is in block/dirty-bitmap.c.

Two current users are converted too.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1476395910-8697-2-git-send-email-jsnow@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-10-24 17:56:07 +02:00
Changlong Xie
a8bbee0edf Backup: export interfaces for extra serialization
Normal backup(sync='none') workflow:
step 1. NBD peformance I/O write from client to server
   qcow2_co_writev
    bdrv_co_writev
     ...
       bdrv_aligned_pwritev
        notifier_with_return_list_notify -> backup_do_cow
         bdrv_driver_pwritev // write new contents

step 2. drive-backup sync=none
   backup_do_cow
   {
    wait_for_overlapping_requests
    cow_request_begin
    for(; start < end; start++) {
            bdrv_co_readv_no_serialising //read old contents from Secondary disk
            bdrv_co_writev // write old contents to hidden-disk
    }
    cow_request_end
   }

step 3. Then roll back to "step 1" to write new contents to Secondary disk.

And for replication, we must make sure that we only read the old contents from
Secondary disk in order to keep contents consistent.

1) Replication workflow of Secondary
                                                         virtio-blk
                                                              ^
------->  1 NBD                                               |
   ||     server                                       3 replication
   ||        ^                                                ^
   ||        |           backing                 backing      |
   ||  Secondary disk 6<-------- hidden-disk 5 <-------- active-disk 4
   ||        |                         ^
   ||        '-------------------------'
   ||           drive-backup sync=none 2

Hence, we need these interfaces to implement coarse-grained serialization between
COW of Secondary disk and the read operation of replication.

Example codes about how to use them:

*#include "block/block_backup.h"

static coroutine_fn int xxx_co_readv()
{
        CowRequest req;
        BlockJob *job = secondary_disk->bs->job;

        if (job) {
              backup_wait_for_overlapping_requests(job, start, end);
              backup_cow_request_begin(&req, job, start, end);
              ret = bdrv_co_readv();
              backup_cow_request_end(&req);
              goto out;
        }
        ret = bdrv_co_readv();
out:
        return ret;
}

Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Wang WeiWei <wangww.fnst@cn.fujitsu.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1469602913-20979-4-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-09-13 11:00:56 +01:00
Wen Congyang
49d3e828f8 Backup: clear all bitmap when doing block checkpoint
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Signed-off-by: Wang WeiWei <wangww.fnst@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1469602913-20979-3-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-09-13 11:00:56 +01:00
Pavel Butsykin
13b9414b57 drive-backup: added support for data compression
The idea is simple - backup is "written-once" data. It is written block
by block and it is large enough. It would be nice to save storage
space and compress it.

The patch adds a flag to the qmp/hmp drive-backup command which enables
block compression. Compression should be implemented in the format driver
to enable this feature.

There are some limitations of the format driver to allow compressed writes.
We can write data only once. Though for backup this is perfectly fine.
These limitations are maintained by the driver and the error will be
reported if we are doing something wrong.

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Jeff Cody <jcody@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: John Snow <jsnow@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-05 19:06:48 +02:00
Paolo Bonzini
0b8b8753e4 coroutine: move entry argument to qemu_coroutine_create
In practice the entry argument is always known at creation time, and
it is confusing that sometimes qemu_coroutine_enter is used with a
non-NULL argument to re-enter a coroutine (this happens in
block/sheepdog.c and tests/test-coroutine.c).  So pass the opaque value
at creation time, for consistency with e.g. aio_bh_new.

Mostly done with the following semantic patch:

@ entry1 @
expression entry, arg, co;
@@
- co = qemu_coroutine_create(entry);
+ co = qemu_coroutine_create(entry, arg);
  ...
- qemu_coroutine_enter(co, arg);
+ qemu_coroutine_enter(co);

@ entry2 @
expression entry, arg;
identifier co;
@@
- Coroutine *co = qemu_coroutine_create(entry);
+ Coroutine *co = qemu_coroutine_create(entry, arg);
  ...
- qemu_coroutine_enter(co, arg);
+ qemu_coroutine_enter(co);

@ entry3 @
expression entry, arg;
@@
- qemu_coroutine_enter(qemu_coroutine_create(entry), arg);
+ qemu_coroutine_enter(qemu_coroutine_create(entry, arg));

@ reentry @
expression co;
@@
- qemu_coroutine_enter(co, NULL);
+ qemu_coroutine_enter(co);

except for the aforementioned few places where the semantic patch
stumbled (as expected) and for test_co_queue, which would otherwise
produce an uninitialized variable warning.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-13 13:26:02 +02:00
Alberto Garcia
70559d499c backup: Add 'job-id' parameter to 'blockdev-backup' and 'drive-backup'
This patch adds a new optional 'job-id' parameter to 'blockdev-backup'
and 'drive-backup', allowing the user to specify the ID of the block
job to be created.

The HMP 'drive_backup' command remains unchanged.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-13 13:26:02 +02:00
Alberto Garcia
7f0317cfc8 blockjob: Add 'job_id' parameter to block_job_create()
When a new job is created, the job ID is taken from the device name of
the BDS. This patch adds a new 'job_id' parameter to let the caller
provide one instead.

This patch also verifies that the ID is always unique and well-formed.
This causes problems in a couple of places where no ID is being set,
because the BDS does not have a device name.

In the case of test_block_job_start() (from test-blockjob-txn.c) we
can simply use this new 'job_id' parameter to set the missing ID.

In the case of img_commit() (from qemu-img.c) we still don't have the
API to make commit_active_start() set the job ID, so we solve it by
setting a default value. We'll get rid of this as soon as we extend
the API.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-07-13 13:26:02 +02:00
Changlong Xie
b48100cf07 blockjob: assert(cb) when create job
Callback for block job should always exist

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1466672241-22485-2-git-send-email-xiecl.fnst@cn.fujitsu.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-06-28 23:08:13 -04:00
Stefan Hajnoczi
5ab4b69ce2 backup: follow AioContext change gracefully
Move s->target to the new AioContext when there is an AioContext change.

The backup_run() coroutine does not use asynchronous I/O so there is no
need to wait for in-flight requests in a BlockJobDriver->pause()
callback.

Guest writes are intercepted by the backup job.  Treat them as guest
activity and do it even while the job is paused.  This is necessary
since the only alternative would be to fail a job that experienced guest
writes during pause once the job is resumed.  In practice the guest
writes don't interfere with AioContext switching since bdrv_drain() is
used by bdrv_set_aio_context().

Loops already contain pause points because of block_job_sleep_ns() calls
in the yield_and_check() helper function.  It is necessary to convert a
raw qemu_coroutine_yield() to block_job_yield() so the
MIRROR_SYNC_MODE_NONE case can pause.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1466096189-6477-9-git-send-email-stefanha@redhat.com
2016-06-20 14:25:41 +01:00
Kevin Wolf
5c438bc68c backup: Use BlockBackend for I/O
This changes the backup block job to use the job's BlockBackend for
performing its I/O. job->bs isn't used by the backup code any more
afterwards.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25 19:04:21 +02:00
Kevin Wolf
8543c27414 backup: Remove bs parameter from backup_do_cow()
Now that we pass the job to the function, bs is implied by that.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-05-25 19:04:21 +02:00
John Snow
12b3e52e48 backup: Pack Notifier within BackupBlockJob
Instead of relying on peeking at bs->job, we want to explicitly get
a reference to the job that was involved in this notifier callback.

Pack the Notifier inside of the BackupBlockJob so we can use
container_of to get a reference back to the BackupBlockJob object.

This cuts out one more case where we rely unnecessarily on bs->job.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-25 19:04:21 +02:00
Kevin Wolf
91ab688379 backup: Don't leak BackupBlockJob in error path
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2016-05-25 19:04:21 +02:00
Kevin Wolf
66a0fae438 blockjob: Don't touch BDS iostatus
Block jobs don't actually make use of the iostatus for their BDSes, but
they manage a separate block job iostatus. Still, they require that it
is enabled for the source BDS and they enable it automatically for the
target and set the error handling mode - which ends up never being used
by the job.

This patch removes all of the BDS iostatus handling from the block job,
which removes another few bs->blk accesses.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:45:31 +02:00
Kevin Wolf
81e254dc83 blockjob: Don't set iostatus of target
When block job errors were introduced, we assigned the iostatus of the
target BDS "just in case". The field has never been accessible for the
user because the target isn't listed in query-block.

Before we can allow the user to have a second BlockBackend on the
target, we need to clean this up. If anything, we would want to set the
iostatus for the internal BB of the job (which we can always do later),
but certainly not for a separate BB which the job doesn't even use.

As a nice side effect, this gets us rid of another bs->blk use.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-05-19 16:45:31 +02:00
Kevin Wolf
09cf9db1bc block: Remove bdrv_(set_)enable_write_cache()
The only remaining users were block jobs (mirror and backup) which
unconditionally enabled WCE on the BlockBackend of the target image. As
these block jobs don't go through BlockBackend for their I/O requests,
they aren't affected by this setting anyway but always get a writeback
mode, so that call can be removed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2016-03-30 12:16:03 +02:00
Veronia Bahaa
f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster
da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Fam Zheng
b2f56462d5 backup: Use Bitmap to replace "s->bitmap"
"s->bitmap" tracks done sectors, we only check bit states without using any
iterator which HBitmap is good for. Switch to "Bitmap" which is simpler and
more memory efficient.

Meanwhile, rename it to done_bitmap, to reflect the intention.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1457412306-18940-2-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-03-14 17:35:05 +01:00
John Snow
4c9bca7e39 block/backup: avoid copying less than full target clusters
During incremental backups, if the target has a cluster size that is
larger than the backup cluster size and we are backing up to a target
that cannot (for whichever reason) pull clusters up from a backing image,
we may inadvertantly create unusable incremental backup images.

For example:

If the bitmap tracks changes at a 64KB granularity and we transmit 64KB
of data at a time but the target uses a 128KB cluster size, it is
possible that only half of a target cluster will be recognized as dirty
by the backup block job. When the cluster is allocated on the target
image but only half populated with data, we lose the ability to
distinguish between zero padding and uninitialized data.

This does not happen if the target image has a backing file that points
to the last known good backup.

Even if we have a backing file, though, it's likely going to be faster
to just buffer the redundant data ourselves from the live image than
fetching it from the backing file, so let's just always round up to the
target granularity.

The same logic applies to backup modes top, none, and full. Copying
fractional clusters without the guarantee of COW is dangerous, but even
if we can rely on COW, it's likely better to just re-copy the data.

Reported-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1456433911-24718-3-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-02-29 14:55:14 -05:00
John Snow
16096a4d47 block/backup: make backup cluster size configurable
64K might not always be appropriate, make this a runtime value.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1456433911-24718-2-git-send-email-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2016-02-29 14:55:14 -05:00
Peter Maydell
80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Fam Zheng
61408b250e block: Don't wait serialising for non-COR read requests
The assertion problem was noticed in 06c3916b35, but it wasn't
completely fixed, because even though the req is not marked as
serialising, it still gets serialised by wait_serialising_requests
against other serialising requests, which could lead to the same
assertion failure.

Fix it by even more explicitly skipping the serialising for this
specific case.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1448962590-2842-2-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-12-03 11:08:07 +08:00
John Snow
78f51fde88 block: Add BlockJobTxn support to backup_run
Allow a BlockJobTxn to be passed into backup_run, which
will allow the job to join a transactional group if present.

Propagate this new parameter outward into new QMP helper
functions in blockdev.c to allow transaction commands to
pass forward their BlockJobTxn object in a forthcoming patch.

[split up from a patch originally by Stefan and Fam. --js]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1446765200-3054-12-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-12 16:22:44 +01:00
John Snow
c347b2c62a block/backup: Rely on commit/abort for cleanup
Switch over to the new .commit/.abort handlers for
cleaning up incremental bitmaps.

[split up from a patch originally by Stefan and Fam. --js]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1446765200-3054-11-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-12 16:22:44 +01:00
Fam Zheng
b976ea3cf5 backup: Extract dirty bitmap handling as a separate function
This will be reused by the coming new transactional completion code.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1446765200-3054-5-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-11-12 16:22:43 +01:00
Max Reitz
373340b26c block: Move I/O status and error actions into BB
These options are only relevant for the user of a whole BDS tree (like a
guest device or a block job) and should thus be moved into the
BlockBackend.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-10-23 18:18:23 +02:00
Wen Congyang
06c3916b35 Backup: don't do copy-on-read in before_write_notifier
We will copy data in before_write_notifier to do backup.
It is a nested I/O request, so we cannot do copy-on-read.

The steps to reproduce it:
1. -drive copy-on-read=on,...  // qemu option
2. drive_backup -f disk0 /path_to_backup.img // monitor command

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Tested-by: Jeff Cody <jcody@redhat.com>
Message-id: 1441682913-14320-3-git-send-email-wency@cn.fujitsu.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2015-09-25 08:37:07 -04:00
Stefan Hajnoczi
17d9716d7b block: keep bitmap if incremental backup job is cancelled
Reclaim the dirty bitmap if an incremental backup block job is
cancelled.  The ret variable may be 0 when the job is cancelled so it's
not enough to check ret < 0.

Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1434380534-7680-1-git-send-email-stefanha@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2015-07-14 21:50:13 -04:00
John Snow
4b80ab2b7d qapi: Rename 'dirty-bitmap' mode to 'incremental'
If we wish to make differential backups a feature that's easy to access,
it might be pertinent to rename the "dirty-bitmap" mode to "incremental"
to make it clear what /type/ of backup the dirty-bitmap is helping us
perform.

This is an API breaking change, but 2.4 has not yet gone live,
so we have this flexibility.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1433463642-21840-2-git-send-email-jsnow@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-07-02 09:20:18 +01:00
Markus Armbruster
cc7a8ea740 Include qapi/qmp/qerror.h exactly where needed
In particular, don't include it into headers.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:41 +02:00
Markus Armbruster
c6bd8c706a qerror: Clean up QERR_ macros to expand into a single string
These macros expand into error class enumeration constant, comma,
string.  Unclean.  Has been that way since commit 13f59ae.

The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.

Clean up as follows:

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

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

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
2015-06-22 18:20:40 +02:00
John Snow
20dca81075 block: Ensure consistent bitmap function prototypes
We often don't need the BlockDriverState for functions
that operate on bitmaps. Remove it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-15-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:10 +02:00
John Snow
d58d845397 qmp: Add support of "dirty-bitmap" sync mode for drive-backup
For "dirty-bitmap" sync mode, the block job will iterate through the
given dirty bitmap to decide if a sector needs backup (backup all the
dirty clusters and skip clean ones), just as allocation conditions of
"top" sync mode.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-11-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:10 +02:00
Fam Zheng
a7282330c0 blockjob: Update function name in comments
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1428069921-2957-5-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
Fam Zheng
c29c1dd312 qmp: Add command 'blockdev-backup'
Similar to drive-backup, but this command uses a device id as target
instead of creating/opening an image file.

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

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

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1418899027-8445-3-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-01-13 11:47:56 +00:00
Stefan Hajnoczi
761731b180 block: let backup blockjob run in BDS AioContext
The backup block job must run in the BlockDriverState AioContext so that
it works with dataplane.

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

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

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1413889440-32577-8-git-send-email-stefanha@redhat.com
2014-11-03 11:41:49 +00:00
Markus Armbruster
097310b53e block: Rename BlockDriverCompletionFunc to BlockCompletionFunc
I'll use it with block backends shortly, and the name is going to fit
badly there.  It's a block layer thing anyway, not just a block driver
thing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:27 +02:00
Kevin Wolf
d40593dd90 block/backup: Fix hang for unaligned image size
When doing a block backup of an image with an unaligned size (with
respect to the BACKUP_CLUSTER_SIZE), qemu would check the allocation
status of sectors after the end of the image. bdrv_is_allocated()
returns a result that is valid for 0 sectors in this case, so the backup
job ran into an endless loop.

Stop looping when seeing a result valid for 0 sectors, we're at EOF then.

The test case looks somewhat unrelated at first sight because I
originally tried to reproduce a different suspected bug that turned out
to not exist. Still a good test case and it accidentally found this one.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2014-07-09 15:50:11 +02:00
Wenchao Xia
a589569f2f qapi: adjust existing defines
In order to let event defines use existing types later, instead of
redefine new ones, some old type defines for spice and vnc are changed,
and BlockErrorAction is moved from block.h to qapi schema. Note that
BlockErrorAction is not merged with BlockdevOnError.

At this point, VncInfo is not made a child of VncBasicInfo, because
VncBasicInfo has mandatory fields where VncInfo makes them optional.

Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-06-23 11:01:25 -04:00
Kevin Wolf
793ed47a7a block: Switch BdrvTrackedRequest to byte granularity
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
2014-01-24 17:40:02 +01:00
Peter Lieven
d32f35cbc5 block: introduce BDRV_REQ_MAY_UNMAP request flag
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28 10:30:51 +01:00
Peter Lieven
aa7bfbfff7 block: add flags to bdrv_*_write_zeroes
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28 10:30:51 +01:00
Fam Zheng
79e14bf778 qapi: make use of new BlockJobType
Switch the string to enum type BlockJobType in BlockJobDriver.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Fam Zheng
3fc4b10af0 blockjob: rename BlockJobType to BlockJobDriver
We will use BlockJobType as the enum type name of block jobs in QAPI,
rename current BlockJobType to BlockJobDriver, which will eventually
become a set of operations, similar to block drivers.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-10-11 10:52:54 +02:00
Paolo Bonzini
bdad13b9de block: make bdrv_co_is_allocated static
bdrv_is_allocated can detect coroutine context and go through a fast
path, similar to other block layer functions.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Fam Zheng
4f6fd3491c block: make bdrv_delete() static
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no
longer public and should be called by bdrv_unref() if refcnt is
decreased to 0.

This is an identical change because effectively, there's no multiple
reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets
bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06 15:25:08 +02:00
Stefan Weil
4c293dc6e4 misc: Fix some typos in names and comments
Most typos were found using a modified version of codespell:

accross -> across
issueing -> issuing
TICNT_THRESHHOLD -> TICNT_THRESHOLD
bandwith -> bandwidth
VCARD_7816_PROPIETARY -> VCARD_7816_PROPRIETARY
occured -> occurred
gaurantee -> guarantee
sofware -> software

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-09-01 18:59:24 +04:00
Alex Bligh
7483d1e547 aio / timers: convert block_job_sleep_ns and co_sleep_ns to new API
Convert block_job_sleep_ns and co_sleep_ns to use the new timer
API.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 19:14:24 +02:00
Ian Main
fc5d3f8432 Implement sync modes for drive-backup.
This patch adds sync-modes to the drive-backup interface and
implements the FULL, NONE and TOP modes of synchronization.

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

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

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

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

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

Signed-off-by: Ian Main <imain@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-07-26 22:01:31 +02:00
Dietmar Maurer
98d2c6f2cd block: add basic backup support to block driver
backup_start() creates a block job that copies a point-in-time snapshot
of a block device to a target block device.

We call backup_do_cow() for each write during backup. That function
reads the original data from the block device before it gets
overwritten.  The data is then written to the target device.

Currently backup cluster size is hardcoded to 65536 bytes.

[I made a number of changes to Dietmar's original patch and folded them
in to make code review easy.  Here is the full list:

 * Drop BackupDumpFunc interface in favor of a target block device
 * Detect zero clusters with buffer_is_zero() and use bdrv_co_write_zeroes()
 * Use 0 delay instead of 1us, like other block jobs
 * Unify creation/start functions into backup_start()
 * Simplify cleanup, free bitmap in backup_run() instead of cb
 * function
 * Use HBitmap to avoid duplicating bitmap code
 * Use bdrv_getlength() instead of accessing ->total_sectors
 * directly
 * Delete the backup.h header file, it is no longer necessary
 * Move ./backup.c to block/backup.c
 * Remove #ifdefed out code
 * Coding style and whitespace cleanups
 * Use bdrv_add_before_write_notifier() instead of blockjob-specific hooks
 * Keep our own in-flight CowRequest list instead of using block.c
   tracked requests.  This means a little code duplication but is much
   simpler than trying to share the tracked requests list and use the
   backup block size.
 * Add on_source_error and on_target_error error handling.
 * Use trace events instead of DPRINTF()

-- stefanha]

Signed-off-by: Dietmar Maurer <dietmar@proxmox.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 09:20:26 +02:00