Commit Graph

65 Commits

Author SHA1 Message Date
Eric Blake
46f5ac205a qobject: Use simpler QDict/QList scalar insertion macros
We now have macros in place to make it less verbose to add a scalar
to QDict and QList, so use them.

Patch created mechanically via:
  spatch --sp-file scripts/coccinelle/qobject.cocci \
    --macro-file scripts/cocci-macro-file.h --dir . --in-place
then touched up manually to fix a couple of '?:' back to original
spacing, as well as avoiding a long line in monitor.c.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170427215821.19397-7-eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-09 09:13:51 +02:00
Eric Blake
de6e7951fe qobject: Drop useless QObject casts
We have macros in place to make it less verbose to add a subtype
of QObject to both QDict and QList. While we have made cleanups
like this in the past (see commit fcfcd8ffc, for example), having
it be automated by Coccinelle makes it easier to maintain.

Patch created mechanically via:
  spatch --sp-file scripts/coccinelle/qobject.cocci \
    --macro-file scripts/cocci-macro-file.h --dir . --in-place
then I verified that no manual touchups were required.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170427215821.19397-5-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2017-05-08 20:32:14 +02:00
Kevin Wolf
d7010dfb68 block: Request child permissions in filter drivers
All callers will have to request permissions for all of their child
nodes. Block drivers that act as simply filters can use the default
implementation of .bdrv_child_perm().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28 20:40:36 +01:00
Kevin Wolf
8b2ff5291f block: Add Error argument to bdrv_attach_child()
It will have to return an error soon, so prepare the callers for it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
2017-02-28 20:40:35 +01:00
Kevin Wolf
7c37f941d0 quorum: Clean up quorum_aio_get()
Make sure that all fields of the new QuorumAIOCB are zeroed when the
function returns even without explicitly setting them. This will protect
us when new fields are added, removes some explicit zero assignment and
makes the code a little nicer to read.

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
a7e159025e quorum: Inline quorum_fifo_aio_cb()
Inlining the function removes some boilerplace code and replaces
recursion by a simple loop, so the code becomes somewhat easier to
understand.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
6847da3808 quorum: Implement .bdrv_co_preadv/pwritev()
This enables byte granularity requests on quorum nodes.

Note that the QMP events emitted by the driver are an external API that
we were careless enough to define as sector based. The offset and length
of requests reported in events are rounded therefore.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
dee66e2882 quorum: Avoid bdrv_aio_writev() for rewrites
Replacing it with bdrv_co_pwritev() prepares us for byte granularity
requests and gets us rid of the last bdrv_aio_*() user in quorum.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
7cd9b3964e quorum: Inline quorum_aio_cb()
This is a conversion to a more natural coroutine style and improves the
readability of the driver.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
0f31977d9d quorum: Do cleanup in caller coroutine
Instead of calling quorum_aio_finalize() deeply nested in what used
to be an AIO callback, do it in the same functions that allocated the
AIOCB.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
ce15dc08ef quorum: Implement .bdrv_co_readv/writev
This converts the quorum block driver from implementing callback-based
interfaces for read/write to coroutine-based ones. This is the first
step that will allow us further simplification of the code.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2017-01-09 13:30:52 +01:00
Kevin Wolf
10c8551968 quorum: Remove s from quorum_aio_get() arguments
There is no point in passing the value of bs->opaque in order to
overwrite it with itself.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2017-01-09 13:30:52 +01:00
Paolo Bonzini
1ba7e15978 quorum: do not allocate multiple iovecs for FIFO strategy
In FIFO mode there are no parallel reads, hence there is no need to
allocate separate buffers and clone the iovecs.

The two cases of quorum_aio_cb are now even more different, and
most of quorum_aio_finalize is only needed in one of them, so split
them in separate functions.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1475685327-22767-3-git-send-email-pbonzini@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-10-24 17:56:06 +02:00
Paolo Bonzini
86ec252c19 quorum: change child_iter to children_read
This simplifies a bit the code by using the usual C "inclusive start,
exclusive end" pattern for ranges.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1475685327-22767-2-git-send-email-pbonzini@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-10-24 17:56:06 +02:00
Kevin Wolf
0d1049c7d1 block: Convert bdrv_aio_writev() to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:26 +02:00
Kevin Wolf
ebb7af2173 block: Convert bdrv_aio_readv() to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-07-05 16:46:26 +02:00
Eduardo Habkost
621ff94d50 error: Remove NULL checks on error_propagate() calls
error_propagate() already ignores local_err==NULL, so there's no
need to check it before calling.

Coccinelle patch used to perform the changes added to
scripts/coccinelle/error_propagate_null.cocci.

Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <1465855078-19435-2-git-send-email-ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-06-20 16:38:13 +02:00
Max Reitz
b97511c7bc block: Propagate AioContext change to all children
Instead of propagating any change of a BDS's AioContext only to its file
and backing children and letting driver-specific code do the rest, just
propagate it to all and drop the thus superfluous implementations of
bdrv_{at,de}tach_aio_context() in Quorum, blkverify and VMDK.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-19 16:45:31 +02:00
Wen Congyang
98292c61bc quorum: implement bdrv_add_child() and bdrv_del_child()
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Message-id: 1462865799-19402-3-git-send-email-xiecl.fnst@cn.fujitsu.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-05-12 15:33:23 +02:00
Fam Zheng
c9e9e9c66c block: Drop superfluous invalidating bs->file from drivers
Now they are invalidated by the block layer, so it's not necessary to
do this in block drivers' implementations of .bdrv_invalidate_cache.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-05-12 15:22:09 +02:00
Alberto Garcia
6049490df4 quorum: Emit QUORUM_REPORT_BAD for reads in fifo mode
If there's an I/O error in one of Quorum children then QEMU
should emit QUORUM_REPORT_BAD. However this is not working with
read-pattern=fifo. This patch fixes this problem.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: d57e39e8d3e8564003a1e2aadbd29c97286eb2d2.1458034554.git.berto@igalia.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-03-17 16:43:30 +01:00
Alberto Garcia
b9c600d207 quorum: Fix crash in quorum_aio_cb()
quorum_aio_cb() emits the QUORUM_REPORT_BAD event if there's
an I/O error in a Quorum child. However sacb->aiocb must be
correctly initialized for this to happen. read_quorum_children() and
read_fifo_child() are not doing this, which results in a QEMU crash.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 8138570d071ba7e25db3736979234a1fd71dbd05.1457610443.git.berto@igalia.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-03-14 17:35:06 +01:00
Changlong Xie
924e8a2bbc quorum: modify vote rules for flush operation
Keep flush interface the same logic as quorum read/write, Otherwise in
following scenario, we'll encounter unexpected errors.

Quorum has two children(A, B). A do flush sucessfully, but B flush failed.
This cause the filesystem of guest become read-only with following errors:

end_request: I/O error, dev vda, sector 11159960
Aborting journal on device vda3-8
EXT4-fs error (device vda3): ext4_journal_start_sb:327: Detected abort journal
EXT4-fs (vda3): Remounting filesystem read-only

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Changlong Xie
0ae053b7e1 qmp event: Refactor QUORUM_REPORT_BAD
Introduce QuorumOpType, and make QUORUM_REPORT_BAD compatible
with it.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Changlong Xie
f38738e212 quorum: fix segfault when read fails in fifo mode
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-02-22 09:49:46 +01:00
Peter Maydell
80c71a241a block: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-01-20 13:36:23 +01:00
Kevin Wolf
4cdd01d32e block: Pass driver-specific options to .bdrv_refresh_filename()
In order to decide whether a blkdebug: filename can be produced or a
json: one is necessary, blkdebug checked whether bs->options had more
options than just "config", "x-image" or "image" (the latter including
nested options). That doesn't work well when generic block layer options
are present.

This patch passes an option QDict to the driver that contains only
driver-specific options, i.e. the options for the general block layer as
well as child nodes are already filtered out. Works much better this
way.

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

This patch was mostly generated by applying a temporary patch:

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

then running:

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

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

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

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-12-17 08:21:28 +01:00
Kevin Wolf
0bd6e91a7e quorum: Convert to BdrvChild
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2015-10-16 15:34:29 +02:00
Wen Congyang
834cb2ada5 quorum: validate vote threshold against num_children even if read-pattern is fifo
We need to use threshold to check if too many write operation fails.
If threshold is larger than num children, we always get write error
event even if all write operations success.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Message-id: 55962F72.3060003@cn.fujitsu.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2015-09-04 21:00:32 +02:00
Sascha Silbe
e94867ed5f block: don't register quorum driver if SHA256 support is unavailable
Commit 488981a4 [block: convert quorum blockdrv to use crypto APIs]
broke qemu-iotest 041 on hosts with GnuTLS < 2.10.0. It converted a
compile-time check to a run-time check at device open time. The result
is that we now advertise a feature (the quorum block driver) that will
never work (on those hosts). There's no way (short of parsing
human-readable error messages) for qemu-iotests or any other API
consumer to recognise that the quorum block driver isn't _actually_
available and shouldn't be used or tested.

Move the run-time check to bdrv_quorum_init() to avoid registering the
quorum block driver if we know it cannot work. This way API consumers
can recognise it's unavailable.

Fixes: 488981a4af
Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1438699705-21761-1-git-send-email-silbe@linux.vnet.ibm.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-08-05 15:19:32 +01:00
Daniel P. Berrange
488981a4af block: convert quorum blockdrv to use crypto APIs
Get rid of direct use of gnutls APIs in quorum blockdrv in
favour of using the crypto APIs. This avoids the need to
do conditional compilation of the quorum driver. It can
simply report an error at file open file instead if the
required hash algorithm isn't supported by QEMU.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-8-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-08 13:11:01 +02:00
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
Eric Blake
fc48ffc39e qobject: Use 'bool' for qbool
We require a C99 compiler, so let's use 'bool' instead of 'int'
when dealing with boolean values.  There are few enough clients
to fix them all in one pass.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-06-22 17:40:00 +02:00
Kevin Wolf
f3930ed0bb block: Move flag inheritance to bdrv_open_inherit()
Instead of letting every caller of bdrv_open() determine the right flags
for its child node manually and pass them to the function, pass the
parent node and the role of the newly opened child (like backing file,
protocol layer, etc.).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2015-06-12 17:04:59 +02:00
Kevin Wolf
ea6828d81b quorum: Use bdrv_open_image()
Besides standardising on a single interface for opening child nodes,
this simplifies the .bdrv_open() implementation of the quorum block
driver by using block layer functionality for handling BlockdevRefs.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2015-06-12 16:58:07 +02:00
Alberto Garcia
9b2aa84f87 block: add bdrv_get_device_or_node_name()
This function gets the device name associated with a BlockDriverState,
or its node name if the device name is empty.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 4fa30aa8d61d9052ce266fd5429a59a14e941255.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28 15:36:09 +02:00
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
Markus Armbruster
7c84b1b831 block: Rename BlockDriverAIOCB* to BlockAIOCB*
I'll use BlockDriverAIOCB 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
Markus Armbruster
bfb197e0d9 block: Eliminate BlockDriverState member device_name[]
device_name[] can become non-empty only in bdrv_new_root() and
bdrv_move_feature_fields().  The latter is used only to undo damage
done by bdrv_swap().  The former is called only by blk_new_with_bs().
Therefore, when a BlockDriverState's device_name[] is non-empty, then
it's been created with a BlockBackend, and vice versa.  Furthermore,
blk_new_with_bs() keeps the two names equal.

Therefore, device_name[] is redundant.  Eliminate it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20 13:41:26 +02:00
Fam Zheng
8007429a99 block: Rename qemu_aio_release -> qemu_aio_unref
Suggested-by: Benoît Canet <benoit.canet@irqsave.net>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:17 +01:00
Fam Zheng
7940e5056b quorum: Convert quorum_aiocb_info.cancel to .cancel_async
Before, we cancel all the child requests with bdrv_aio_cancel, then free
the acb..

Now we just kick off asynchronous cancellation of child requests and
return, we know quorum_aio_cb will be called later, so in the end
quorum_aio_finalize will take care of calling the caller's cb.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:13 +01:00
Liu Yuan
997dd8df3e quorum: fix quorum_aio_cancel()
For a fifo read pattern, we only have one running aio (possible other cases that
has less number than num_children in the future), so we need to check if
.acb is NULL against bdrv_aio_cancel() to avoid segfault.

Cc: Eric Blake <eblake@redhat.com>
Cc: Benoit Canet <benoit@irqsave.net>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22 11:39:12 +01:00
Fam Zheng
8df3abfcee quorum: Fix leak of opts in quorum_open
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-29 17:10:18 +01:00
Liu Yuan
a9db86b223 block/quorum: add simple read pattern support
This patch adds single read pattern to quorum driver and quorum vote is default
pattern.

For now we do a quorum vote on all the reads, it is designed for unreliable
underlying storage such as non-redundant NFS to make sure data integrity at the
cost of the read performance.

For some use cases as following:

        VM
  --------------
  |            |
  v            v
  A            B

Both A and B has hardware raid storage to justify the data integrity on its own.
So it would help performance if we do a single read instead of on all the nodes.
Further, if we run VM on either of the storage node, we can make a local read
request for better performance.

This patch generalize the above 2 nodes case in the N nodes. That is,

vm -> write to all the N nodes, read just one of them. If single read fails, we
try to read next node in FIFO order specified by the startup command.

The 2 nodes case is very similar to DRBD[1] though lack of auto-sync
functionality in the single device/node failure for now. But compared with DRBD
we still have some advantages over it:

- Suppose we have 20 VMs running on one(assume A) of 2 nodes' DRBD backed
storage. And if A crashes, we need to restart all the VMs on node B. But for
practice case, we can't because B might not have enough resources to setup 20 VMs
at once. So if we run our 20 VMs with quorum driver, and scatter the replicated
images over the data center, we can very likely restart 20 VMs without any
resource problem.

After all, I think we can build a more powerful replicated image functionality
on quorum and block jobs(block mirror) to meet various High Availibility needs.

E.g, Enable single read pattern on 2 children,

-drive driver=quorum,children.0.file.filename=0.qcow2,\
children.1.file.filename=1.qcow2,read-pattern=fifo,vote-threshold=1

[1] http://en.wikipedia.org/wiki/Distributed_Replicated_Block_Device

[Dropped \n from an error_setg() error message
--Stefan]

Cc: Benoit Canet <benoit@irqsave.net>
Cc: Eric Blake <eblake@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-08-29 10:46:58 +01:00
Max Reitz
fafcfe228d quorum: Implement bdrv_refresh_filename()
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-08-20 14:31:56 +02:00
Benoît Canet
cf29a570a7 quorum: Add the rewrite-corrupted parameter to quorum
On read operations when this parameter is set and some replicas are corrupted
while quorum can be reached quorum will proceed to rewrite the correct version
of the data to fix the corrupted replicas.

This will shine with SSD where the FTL will remap the same block at another
place on rewrite.

Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-06-27 14:18:17 +02:00
Wenchao Xia
fe069d9d59 qapi event: convert QUORUM events
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 11:12:28 -04:00
Stefan Hajnoczi
e3625d3d6a quorum: implement .bdrv_detach/attach_aio_context()
Implement .bdrv_detach/attach_aio_context() interfaces to propagate
detach/attach to BDRVQuorumState->bs[] children.  The block layer takes
care of ->file and ->backing_hd but doesn't know about our ->bs[]
BlockDriverStates, which is also part of the graph.

Reviewed-by: Benoît Canet <benoit.canet@irqsave.net>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-04 09:56:11 +02:00