Commit Graph

4079 Commits

Author SHA1 Message Date
Peter Maydell
a29644590f nbd patches for 2019-01-05
Error and trace improvements in NBD code, such as less noise for
 common disconnect scenarios.
 
 - Vladimir Sementsov-Ogievskiy: 0/3 nbd-client: drop extra error noise
 - Eric Blake: portions of 0/22 nbd: add qemu-nbd --list
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Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2019-01-05' into staging

nbd patches for 2019-01-05

Error and trace improvements in NBD code, such as less noise for
common disconnect scenarios.

- Vladimir Sementsov-Ogievskiy: 0/3 nbd-client: drop extra error noise
- Eric Blake: portions of 0/22 nbd: add qemu-nbd --list

# gpg: Signature made Sat 05 Jan 2019 13:58:54 GMT
# gpg:                using RSA key A7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>"
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>"
# gpg:                 aka "[jpeg image of size 6874]"
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2019-01-05:
  nbd/client: Drop pointless buf variable
  qemu-nbd: Fail earlier for -c/-d on non-linux
  nbd/client: More consistent error messages
  nbd: Document timeline of various features
  qemu-nbd: Use program name in error messages
  block/nbd-client: use traces instead of noisy error_report_err
  nbd/client: Trace all server option error messages
  nbd: publish _lookup functions

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-01-07 11:55:52 +00:00
Vladimir Sementsov-Ogievskiy
d8b4bad846 block/nbd-client: use traces instead of noisy error_report_err
Reduce extra noise of nbd-client, change 083 correspondingly.

In various commits (be41c100 in 2.10, f140e300 in 2.11, 78a33ab
in 2.12), we added spots where qemu as an NBD client would report
problems communicating with the server to stderr, because there
was no where else to send the error to.  However, this is racy,
particularly since the most common source of these errors is when
either the client or the server abruptly hangs up, leaving one
coroutine to report the error only if it wins (or loses) the
race in attempting the read from the server before another
thread completes its cleanup of a protocol error that caused the
disconnect in the first place.  The race is also apparent in the
fact that differences in the flush behavior of the server can
alter the frequency of encountering the race in the client (see
commit 6d39db96).

Rather than polluting stderr, it's better to just trace these
situations, for use by developers debugging a flaky connection,
particularly since the real error that either triggers the abrupt
disconnection in the first place, or that results from the EIO
when a request can't receive a reply, DOES make it back to the
user in the normal Error propagation channels.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20181102151152.288399-4-vsementsov@virtuozzo.com>
[eblake: drop depedence on error hint, enhance commit message]
Signed-off-by: Eric Blake <eblake@redhat.com>
2019-01-04 17:34:58 -06:00
yuchenlin
39a0408e76 dmg: don't skip zero chunk
The dmg file has many tables which describe: "start from sector XXX to
sector XXX, the compression method is XXX and where the compressed data
resides on".

Each sector in the expanded file should be covered by a table. The table
will describe the offset of compressed data (or raw depends on the type)
in the dmg.

For example:

[-----------The expanded file------------]
[---bzip table ---]/* zeros */[---zlib---]
    ^
    | if we want to read this sector.

we will find bzip table which contains this sector, and get the
compressed data offset, read it from dmg, uncompress it, finally write to
expanded file.

If we skip zero chunk (table), some sector cannot find the table which
will cause search_chunk() return s->n_chunks, dmg_read_chunk() return -1
and finally causing dmg_co_preadv() return EIO.

See:

[-----------The expanded file------------]
[---bzip table ---]/* zeros */[---zlib---]
                    ^
                    | if we want to read this sector.

Oops, we cannot find the table contains it...

In the original implementation, we don't have zero table. When we try to
read sector inside the zero chunk. We will get EIO, and skip reading.

After this patch, we treat zero chunk the same as ignore chunk, it will
directly write zero and avoid some sector may not find the table.

After this patch:

[-----------The expanded file------------]
[---bzip table ---][--zeros--][---zlib---]

Signed-off-by: yuchenlin <npes87184@gmail.com>
Reviewed-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190103114700.9686-4-npes87184@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-01-04 11:15:09 +00:00
yuchenlin
e80fcf590e dmg: use enumeration type instead of hard coding number
Signed-off-by: yuchenlin <npes87184@gmail.com>
Reviewed-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190103114700.9686-3-npes87184@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-01-04 11:15:09 +00:00
yuchenlin
5ef40828ba dmg: fix binary search
There is a possible hang in original binary search implementation. That is
if chunk1 = 4, chunk2 = 5, chunk3 = 4, and we go else case.

The chunk1 will be still 4, and so on.

Signed-off-by: yuchenlin <npes87184@gmail.com>
Message-id: 20190103114700.9686-2-npes87184@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-01-04 11:15:09 +00:00
Julio Faracco
b47c7d5325 dmg: Fixing wrong dmg block type value for block terminator.
This is a trivial patch to fix a wrong value for block terminator.
The old value was 0x7fffffff which is wrong. It was not affecting the
code because QEMU dmg block is not handling block terminator right now.
Neverthless, it should be fixed.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Reviewed-by: yuchenlin <yuchenlin@synology.com>
Message-id: 20181228145055.18039-1-jcfaracco@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-01-04 11:06:02 +00:00
Stefan Hajnoczi
537c3d4f64 block/mirror: add missing coroutine_fn annotations
Marking a function coroutine_fn currently has no effect on the compiler,
but it documents that this function must be called from coroutine
context and it may yield.  This is important information for the
programmer.

Also, if we ever transition to a stackless coroutine implementation,
then it's likely that the annotation will become mandatory so the
compiler can use the correct calling convention for coroutine functions.

Cc: Max Reitz <mreitz@redhat.com>
Cc: John Snow <jsnow@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia
2e891722c5 block: Remove flags parameter from bdrv_reopen_queue()
Now that all callers are passing all flag changes as QDict options,
the flags parameter is no longer necessary, so we can get rid of it.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia
3c4e964762 block: Clean up reopen_backing_file() in block/replication.c
This function is used to put the hidden and secondary disks in
read-write mode before launching the backup job, and back in read-only
mode afterwards.

This patch does the following changes:

  - Use an options QDict with the "read-only" option instead of
    passing the changes as flags only.

  - Simplify the code (it was unnecessarily complicated and verbose).

  - Fix a bug due to which the secondary disk was not being put back
    in read-only mode when writable=false (because in this case
    orig_secondary_flags always had the BDRV_O_RDWR flag set).

  - Stop clearing the BDRV_O_INACTIVE flag.

The flags parameter to bdrv_reopen_queue() becomes redundant and we'll
be able to get rid of it in a subsequent patch.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia
1ba7938895 block: Use bdrv_reopen_set_read_only() in the mirror driver
The 'block-commit' QMP command is implemented internally using two
different drivers. If the source image is the active layer then the
mirror driver is used (commit_active_start()), otherwise the commit
driver is used (commit_start()).

In both cases the destination image must be put temporarily in
read-write mode. This is done correctly in the latter case, but what
commit_active_start() does is copy all flags instead.

This patch replaces the bdrv_reopen() calls in that function with
bdrv_reopen_set_read_only() so that only the read-only status is
changed.

A similar change is made in mirror_exit(), which is also used by the
'drive-mirror' and 'blockdev-mirror' commands.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia
e7d22f8bc6 block: Use bdrv_reopen_set_read_only() in stream_start/complete()
This patch replaces the bdrv_reopen() calls that set and remove the
BDRV_O_RDWR flag with the new bdrv_reopen_set_read_only() function.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:02 +01:00
Alberto Garcia
c742a3643f block: Use bdrv_reopen_set_read_only() in bdrv_commit()
This patch replaces the bdrv_reopen() calls that set and remove the
BDRV_O_RDWR flag with the new bdrv_reopen_set_read_only() function.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:01 +01:00
Alberto Garcia
e70cdc57da block: Use bdrv_reopen_set_read_only() in commit_start/complete()
This patch replaces the bdrv_reopen() calls that set and remove the
BDRV_O_RDWR flag with the new bdrv_reopen_set_read_only() function.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:55:01 +01:00
Kevin Wolf
0342567115 file-posix: Avoid aio_worker() for QEMU_AIO_IOCTL
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

This was the last user of aio_worker(), so the function goes away now.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:54:49 +01:00
Kevin Wolf
2f3a7ab39b file-posix: Switch to .bdrv_co_ioctl
No real reason to keep using the callback based mechanism here when the
rest of the file-posix driver is coroutine based. Changing it brings
ioctls more in line with how other request types work.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
c9db2b6489 file-posix: Remove paio_submit_co()
The function is not used any more, remove it.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
999e6b69ce file-posix: Avoid aio_worker() for QEMU_AIO_READ/WRITE
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
54c7ca1b81 file-posix: Move read/write operation logic out of aio_worker()
aio_worker() for reads and writes isn't boring enough yet. It still does
some postprocessing for handling short reads and turning the result into
the right return value.

However, there is no reason why handle_aiocb_rw() couldn't do the same,
and even without duplicating code between the read and write path. So
move the code there.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
06dc9bd571 file-posix: Avoid aio_worker() for QEMU_AIO_FLUSH
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
46ee0f462b file-posix: Avoid aio_worker() for QEMU_AIO_DISCARD
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
7154d8ae66 file-posix: Avoid aio_worker() for QEMU_AIO_WRITE_ZEROES
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
58a209c437 file-posix: Avoid aio_worker() for QEMU_AIO_COPY_RANGE
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
29cb4c01e7 file-posix: Avoid aio_worker() for QEMU_AIO_TRUNCATE
aio_worker() doesn't add anything interesting, it's only a useless
indirection. Call the handler function directly instead.

As we know that this handler function is only called from coroutine
context and the coroutine stays around until the worker thread finishes,
we can keep RawPosixAIOData on the stack.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
5d5de25005 file-posix: Factor out raw_thread_pool_submit()
Getting the thread pool of the AioContext of a block node and scheduling
some work in it is an operation that is already done twice, and we'll
get more instances. Factor it out into a separate function.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Kevin Wolf
d57c44d00f file-posix: Reorganise RawPosixAIOData
RawPosixAIOData contains a lot of fields for several separate operations
that are to be processed in a worker thread and that need different
parameters. The struct is currently rather unorganised, with unions that
cover some, but not all operations, and even one #define for field names
instead of a union.

Clean this up to have some common fields and a single union. As a side
effect, on x86_64 the struct shrinks from 72 to 48 bytes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Vladimir Sementsov-Ogievskiy
e23c9d7a1c qcow2: do decompression in threads
Do decompression in threads, like it is already done for compression.
This improves asynchronous compressed reads performance.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Vladimir Sementsov-Ogievskiy
c3c10f7295 qcow2: aio support for compressed cluster read
Allocate buffers locally and release qcow2 lock. Than, reads inside
qcow2_co_preadv_compressed may be done in parallel, however all
decompression is still done synchronously. Let's improve it in the
following commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:41 +01:00
Vladimir Sementsov-Ogievskiy
c068a1cd52 qcow2: use byte-based read in qcow2_decompress_cluster
We are gradually moving away from sector-based interfaces, towards
byte-based.  Get rid of it here too.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
341926ab83 qcow2: refactor decompress_buffer
- make it look more like a pair of qcow2_compress - rename the function
  and its parameters
- drop extra out_len variable, check filling of output buffer by strm
  structure itself
- fix code style
- add some documentation

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
f4b3e2a960 qcow2: move decompression from qcow2-cluster.c to qcow2.c
Compression is done in threads in qcow2.c. We want to do decompression
in the same way, so, firstly, move it to the same file.

The only change is braces around if-body in decompress_buffer, to
satisfy checkpatch.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
6994fd78b9 qcow2: make more generic interface for qcow2_compress
Give explicit size both for source and destination buffers, to make it
similar with decompression path and than cleanly reuse parameter
structure for decompression threads.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
19a4448853 qcow2: use Z_OK instead of 0 for deflateInit2 return code check
Use appropriate macro, corresponding to deflateInit2 spec.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
3a75187fd8 block/backup: drop unused synchronization interface
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
e4f9752c4a block/replication: drop extra synchronization
After commit f8d59dfb40
    "block/backup: fix fleecing scheme: use serialized writes" fleecing
(specifically reading from backup target, when backup source is in
backing chain of backup target) is safe, because all backup-job writes
to target are serialized. Therefore we don't need additional
synchronization for these reads.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Julio Faracco
95a156f689 dmg: exchanging hardcoded dmg UDIF block types to enum.
This change is better to understand what kind of block type is being
handled by the code. Using a syntax similar to the DMG documentation is
easier than tracking all hex values assigned to a block type.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Julio Faracco
7a40b418ec dmg: including dmg-lzfse module inside dmg block driver.
This commit includes the support to new module dmg-lzfse into dmg block
driver. It includes the support for block type ULFO (0x80000007).

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Julio Faracco
83bc1f9768 configure: adding support to lzfse library.
This commit includes the support to lzfse opensource library. With this
library dmg block driver can decompress images with this type of
compression inside.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Julio Faracco
c13e80d792 block: adding lzfse decompressing support as a module.
QEMU dmg support includes zlib and bzip2, but it does not contains lzfse
support. This commit adds the source file to extend compression support
for new DMGs.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-14 11:52:40 +01:00
Vladimir Sementsov-Ogievskiy
c972fa123c crypto: support multiple threads accessing one QCryptoBlock
The two thing that should be handled are cipher and ivgen. For ivgen
the solution is just mutex, as iv calculations should not be long in
comparison with encryption/decryption. And for cipher let's just keep
per-thread ciphers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-12 11:16:49 +00:00
Peter Maydell
9225cd127d nbd patches for 2018-12-03
Improve x-dirty-bitmap handling for experimenting with pull mode
 incremental backups.
 
 - Eric Blake: 0/3 NBD dirty bitmap cleanups
 -----BEGIN PGP SIGNATURE-----
 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg
 
 iQEcBAABCAAGBQJcBVInAAoJEKeha0olJ0Nq+68H/RoRtXAycWm1bNidVNC9J8pO
 hkXsZwe39V/6Hl5eXch5J6K9V+443A4+WJSpvfISnB7jKEIHQ2GVMiuXPjmeyap+
 BIbAlHt+frQYz+x1E6fKrLE67mxQViRCQrfx8ijDRUJTUlDxq+yPDjwmGk25DRDt
 zlFqpkCr1NhEREm6JDNmM/WJqBaueSAXY5Fi7MqeHTyRKlZ5RclZaZ5bw4YpB+ip
 kwsWPHsz9uoe9caMxcdU0Y8PqB7KwvwJ+4RjtGpFgp0Auqe2FvaRyiqYE4n5EU2S
 5kvbvKgGK1XUe4RyBLVg1cqcB/LoHLbNohJUJ03pdU1anxcjKIDEv/Oh801OPmE=
 =w1HF
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2018-12-03' into staging

nbd patches for 2018-12-03

Improve x-dirty-bitmap handling for experimenting with pull mode
incremental backups.

- Eric Blake: 0/3 NBD dirty bitmap cleanups

# gpg: Signature made Mon 03 Dec 2018 15:56:23 GMT
# gpg:                using RSA key A7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>"
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>"
# gpg:                 aka "[jpeg image of size 6874]"
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2018-12-03:
  nbd/client: Send NBD_CMD_DISC if open fails after connect
  nbd/client: Make x-dirty-bitmap more reliable
  nbd/server: Advertise all contexts in response to bare LIST

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-12-03 17:43:20 +00:00
Vladimir Sementsov-Ogievskiy
d12ade5732 mirror: fix dead-lock
Let start from the beginning:

Commit b9e413dd37 (in 2.9)
"block: explicitly acquire aiocontext in aio callbacks that need it"
added pairs of aio_context_acquire/release to mirror_write_complete and
mirror_read_complete, when they were aio callbacks for blk_aio_* calls.

Then, commit 2e1990b26e (in 3.0) "block/mirror: Convert to coroutines"
dropped these blk_aio_* calls, than mirror_write_complete and
mirror_read_complete are not callbacks more, and don't need additional
aiocontext acquiring. Furthermore, mirror_read_complete calls
blk_co_pwritev inside these pair of aio_context_acquire/release, which
leads to the following dead-lock with mirror:

 (gdb) info thr
   Id   Target Id         Frame
   3    Thread (LWP 145412) "qemu-system-x86" syscall ()
   2    Thread (LWP 145416) "qemu-system-x86" __lll_lock_wait ()
 * 1    Thread (LWP 145411) "qemu-system-x86" __lll_lock_wait ()

 (gdb) bt
 #0  __lll_lock_wait ()
 #1  _L_lock_812 ()
 #2  __GI___pthread_mutex_lock
 #3  qemu_mutex_lock_impl (mutex=0x561032dce420 <qemu_global_mutex>,
     file=0x5610327d8654 "util/main-loop.c", line=236) at
     util/qemu-thread-posix.c:66
 #4  qemu_mutex_lock_iothread_impl
 #5  os_host_main_loop_wait (timeout=480116000) at util/main-loop.c:236
 #6  main_loop_wait (nonblocking=0) at util/main-loop.c:497
 #7  main_loop () at vl.c:1892
 #8  main

Printing contents of qemu_global_mutex, I see that "__owner = 145416",
so, thr1 is main loop, and now it wants BQL, which is owned by thr2.

 (gdb) thr 2
 (gdb) bt
 #0  __lll_lock_wait ()
 #1  _L_lock_870 ()
 #2  __GI___pthread_mutex_lock
 #3  qemu_mutex_lock_impl (mutex=0x561034d25dc0, ...
 #4  aio_context_acquire (ctx=0x561034d25d60)
 #5  dma_blk_cb
 #6  dma_blk_io
 #7  dma_blk_read
 #8  ide_dma_cb
 #9  bmdma_cmd_writeb
 #10 bmdma_write
 #11 memory_region_write_accessor
 #12 access_with_adjusted_size
 #15 flatview_write
 #16 address_space_write
 #17 address_space_rw
 #18 kvm_handle_io
 #19 kvm_cpu_exec
 #20 qemu_kvm_cpu_thread_fn
 #21 qemu_thread_start
 #22 start_thread
 #23 clone ()

Printing mutex in fr 2, I see "__owner = 145411", so thr2 wants aio
context mutex, which is owned by thr1. Classic dead-lock.

Then, let's check that aio context is hold by mirror coroutine: just
print coroutine stack of first tracked request in mirror job target:

 (gdb) [...]
 (gdb) qemu coroutine 0x561035dd0860
 #0  qemu_coroutine_switch
 #1  qemu_coroutine_yield
 #2  qemu_co_mutex_lock_slowpath
 #3  qemu_co_mutex_lock
 #4  qcow2_co_pwritev
 #5  bdrv_driver_pwritev
 #6  bdrv_aligned_pwritev
 #7  bdrv_co_pwritev
 #8  blk_co_pwritev
 #9  mirror_read_complete () at block/mirror.c:232
 #10 mirror_co_read () at block/mirror.c:370
 #11 coroutine_trampoline
 #12 __start_context

Yes it is mirror_read_complete calling blk_co_pwritev after acquiring
aio context.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-12-03 16:50:58 +01:00
Eric Blake
c688e6ca7b nbd/client: Send NBD_CMD_DISC if open fails after connect
If nbd_client_init() fails after we are already connected,
then the server will spam logs with:

Disconnect client, due to: Unexpected end-of-file before all bytes were read

unless we gracefully disconnect before closing the connection.

Ways to trigger this:

$ opts=driver=nbd,export=foo,server.type=inet,server.host=localhost,server.port=10809
$  qemu-img map --output=json --image-opts $opts,read-only=off
$  qemu-img map --output=json --image-opts $opts,x-dirty-bitmap=nosuch:

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181130023232.3079982-4-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2018-11-30 14:13:37 -06:00
Eric Blake
47829c4079 nbd/client: Make x-dirty-bitmap more reliable
The implementation of x-dirty-bitmap in qemu 3.0 (commit 216ee365)
silently falls back to treating the server as not supporting
NBD_CMD_BLOCK_STATUS if a requested meta_context name was not
negotiated, which in turn means treating the _entire_ image as
data. Since our hack relied on using 'qemu-img map' to view
which portions of the image were dirty by seeing what the
redirected bdrv_block_status() treats as holes, this means
that our fallback treats the entire image as clean.  Better
would have been to treat the entire image as dirty, or to fail
to connect because the user's request for a specific context
could not be honored. This patch goes with the latter.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181130023232.3079982-3-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2018-11-30 14:11:20 -06:00
Max Reitz
577a133988 file-posix: Fix shared locks on reopen commit
s->locked_shared_perm is the set of bits locked in the file, which is
the inverse of the permissions actually shared.  So we need to pass them
as they are to raw_apply_lock_bytes() instead of inverting them again.

Reported-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-19 14:32:01 +01:00
Eric Blake
77d6a21558 qcow2: Don't allow overflow during cluster allocation
Our code was already checking that we did not attempt to
allocate more clusters than what would fit in an INT64 (the
physical maximimum if we can access a full off_t's worth of
data).  But this does not catch smaller limits enforced by
various spots in the qcow2 image description: L1 and normal
clusters of L2 are documented as having bits 63-56 reserved
for other purposes, capping our maximum offset at 64PB (bit
55 is the maximum bit set).  And for compressed images with
2M clusters, the cap drops the maximum offset to bit 48, or
a maximum offset of 512TB.  If we overflow that offset, we
would write compressed data into one place, but try to
decompress from another, which won't work.

It's actually possible to prove that overflow can cause image
corruption without this patch; I'll add the iotests separately
in the next commit.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-11-19 12:51:40 +01:00
Kevin Wolf
443ba6befa vvfat: Fix memory leak
Don't leak 'cluster' in the mapping == NULL case. Found by Coverity
(CID 1055918).

Fixes: 8d9401c279
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2018-11-19 12:51:40 +01:00
Liam Merwick
7cb6d3c9be qcow2: Read outside array bounds in qcow2_pre_write_overlap_check()
The commit for 0e4e4318ea increments QCOW2_OL_MAX_BITNR but does not
add an array entry for QCOW2_OL_BITMAP_DIRECTORY_BITNR to metadata_ol_names[].
As a result, an array dereference of metadata_ol_names[8] in
qcow2_pre_write_overlap_check() could result in a read outside of the array bounds.

Fixes: 0e4e4318ea ('qcow2: add overlap check for bitmap directory')

Cc: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Liam Merwick <Liam.Merwick@oracle.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 1541453919-25973-6-git-send-email-Liam.Merwick@oracle.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-11-12 17:49:21 +01:00
Liam Merwick
8d9401c279 block: Fix potential Null pointer dereferences in vvfat.c
The calls to find_mapping_for_cluster() may return NULL but it
isn't always checked for before dereferencing the value returned.
Additionally, add some asserts to cover cases where NULL can't
be returned but which might not be obvious at first glance.

Signed-off-by: Liam Merwick <Liam.Merwick@oracle.com>
Message-id: 1541453919-25973-5-git-send-email-Liam.Merwick@oracle.com
[mreitz: Dropped superfluous check of "mapping" following an assertion
         that it is not NULL, and fixed some indentation]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-11-12 17:49:21 +01:00
Liam Merwick
602414d123 block: Null pointer dereference in blk_root_get_parent_desc()
The dev_id returned by the call to blk_get_attached_dev_id() in
blk_root_get_parent_desc() can be NULL (an internal call to
object_get_canonical_path may have returned NULL).

Instead of just checking this case before before dereferencing,
adjust blk_get_attached_dev_id() to return the empty string if no
object path can be found (similar to the case when blk->dev is NULL
and an empty string is returned).

Signed-off-by: Liam Merwick <Liam.Merwick@oracle.com>
Message-id: 1541453919-25973-3-git-send-email-Liam.Merwick@oracle.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-11-12 17:49:21 +01:00
Jeff Cody
2f74013655 block: Make more block drivers compile-time configurable
This adds configure options to control the following block drivers:

* Bochs
* Cloop
* Dmg
* Qcow (V1)
* Vdi
* Vvfat
* qed
* parallels
* sheepdog

Each of these defaults to being enabled.

Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20181107063644.2254-1-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-11-12 17:49:21 +01:00