Commit Graph

5541 Commits

Author SHA1 Message Date
Paolo Bonzini
620c5cb5da nbd: document what is protected by the CoMutexes
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-10-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:42 -05:00
Paolo Bonzini
a80a9a1c73 nbd: take receive_mutex when reading requests[].receiving
requests[].receiving is set by nbd_receive_replies() under the receive_mutex;
Read it under the same mutex as well.  Waking up receivers on errors happens
after each reply finishes processing, in nbd_co_receive_one_chunk().
If there is no currently-active reply, there are two cases:

* either there is no active request at all, in which case no
element of request[] can have .receiving = true

* or nbd_receive_replies() must be running and owns receive_mutex;
in that case it will get back to nbd_co_receive_one_chunk() because
the socket has been shutdown, and all waiting coroutines will wake up
in turn.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-9-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:41 -05:00
Paolo Bonzini
dba5156c0e nbd: move s->state under requests_lock
Remove the confusing, and most likely wrong, atomics.  The only function
that used to be somewhat in a hot path was nbd_client_connected(),
but it is not anymore after the previous patches.

The same logic is used both to check if a request had to be reissued
and also in nbd_reconnecting_attempt().  The former cases are outside
requests_lock, while nbd_reconnecting_attempt() does have the lock,
therefore the two have been separated in the previous commit.
nbd_client_will_reconnect() can simply take s->requests_lock, while
nbd_reconnecting_attempt() can inline the access now that no
complicated atomics are involved.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-8-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:39 -05:00
Paolo Bonzini
8d45185cb7 nbd: code motion and function renaming
Prepare for the next patch, so that the diff is less confusing.

nbd_client_connecting is moved closer to the definition point.

nbd_client_connecting_wait() is kept only for the reconnection
logic; when it is used to check if a request has to be reissued,
use the renamed function nbd_client_will_reconnect().  In the
next patch, the two cases will have different locking requirements.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-7-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:38 -05:00
Paolo Bonzini
ee19d953ec nbd: use a QemuMutex to synchronize yanking, reconnection and coroutines
The condition for waiting on the s->free_sema queue depends on
both s->in_flight and s->state.  The latter is currently using
atomics, but this is quite dubious and probably wrong.

Because s->state is written in the main thread too, for example by
the yank callback, it cannot be protected by a CoMutex.  Introduce a
separate lock that can be used by nbd_co_send_request(); later on this
lock will also be used for s->state.  There will not be any contention
on the lock unless there is a yank or reconnect, so this is not
performance sensitive.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-6-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:37 -05:00
Paolo Bonzini
8610b4491f nbd: keep send_mutex/free_sema handling outside nbd_co_do_establish_connection
Elevate s->in_flight early so that other incoming requests will wait
on the CoQueue in nbd_co_send_request; restart them after getting back
from nbd_reconnect_attempt.  This could be after the reconnect timer or
nbd_cancel_in_flight have cancelled the attempt, so there is no
need anymore to cancel the requests there.

nbd_co_send_request now handles both stopping and restarting pending
requests after a successful connection, and there is no need to
hold send_mutex in nbd_co_do_establish_connection.  The current setup
is confusing because nbd_co_do_establish_connection is called both with
send_mutex taken and without it.  Before the patch it uses free_sema which
(at least in theory...) is protected by send_mutex, after the patch it
does not anymore.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-5-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: wrap long line]
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:36 -05:00
Paolo Bonzini
172f5f1a40 nbd: remove peppering of nbd_client_connected
It is unnecessary to check nbd_client_connected() because every time
s->state is moved out of NBD_CLIENT_CONNECTED the socket is shut down
and all coroutines are resumed.

The only case where it was actually needed is when the NBD
server disconnects and there is no reconnect-delay.  In that
case, nbd_receive_replies() does not set s->reply.handle and
nbd_co_do_receive_one_chunk() cannot continue.  For that one case,
check the return value of nbd_receive_replies().

As to the others:

* nbd_receive_replies() can put the current coroutine to sleep if another
reply is ongoing; then it will be woken by nbd_channel_error(), called
by the ongoing reply.  Or it can try itself to read a reply header and
fail, thus calling nbd_channel_error() itself.

* nbd_co_send_request() will write the body of the request and fail

* nbd_reply_chunk_iter_receive() will call nbd_co_receive_one_chunk()
and then nbd_co_do_receive_one_chunk(), which will handle the failure as
above; or it will just detect a previous call to nbd_iter_channel_error()
via iter->ret < 0.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-4-pbonzini@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:36 -05:00
Paolo Bonzini
0c43c6fc89 nbd: mark more coroutine_fns
Several coroutine functions in block/nbd.c are not marked as such.  This
patch adds a few more markers; it is not exhaustive, but it focuses
especially on:

- places that wake other coroutines, because aio_co_wake() has very
different semantics inside a coroutine (queuing after yield vs. entering
immediately);

- functions with _co_ in their names, to avoid confusion

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-3-pbonzini@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:35 -05:00
Paolo Bonzini
8846b7d1c1 nbd: safeguard against waking up invalid coroutine
The .reply_possible field of s->requests is never set to false.  This is
not a problem as it is only a safeguard to detect protocol errors,
but it's sloppy.  In fact, the field is actually not necessary at all,
because .coroutine is set to NULL in NBD_FOREACH_REPLY_CHUNK after
receiving the last chunk.  Thus, replace .reply_possible with .coroutine
and move the check before deciding the fate of this request.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20220414175756.671165-2-pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Reviewed-by: Lukas Straub <lukasstraub2@web.de>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:16:24 -05:00
Vladimir Sementsov-Ogievskiy
1466ef6cbe qapi: rename BlockDirtyBitmapMergeSource to BlockDirtyBitmapOrStr
Rename the type to be reused. Old name is "what is it for". To be
natively reused for other needs, let's name it exactly "what is it".

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Message-Id: <20220314213226.362217-2-v.sementsov-og@mail.ru>
[eblake: Adjust S-o-b to Vladimir's new email, with permission]
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-04-26 13:13:50 -05:00
Denis V. Lunev
80dd5aff1b block: add 'force' parameter to 'blockdev-change-medium' command
'blockdev-change-medium' is a convinient wrapper for the following
sequence of commands:
 * blockdev-open-tray
 * blockdev-remove-medium
 * blockdev-insert-medium
 * blockdev-close-tray
and should be used f.e. to change ISO image inside the CD-ROM tray.
Though the guest could lock the tray and some linux guests like
CentOS 8.5 actually does that. In this case the execution if this
command results in the error like the following:
  Device 'scsi0-0-1-0' is locked and force was not specified,
  wait for tray to open and try again.

This situation is could be resolved 'blockdev-open-tray' by passing
flag 'force' inside. Thus is seems reasonable to add the same
capability for 'blockdev-change-medium' too.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@openvz.org>
Acked-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Hanna Reitz <hreitz@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220412221846.280723-1-den@openvz.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-04-25 12:02:36 +02:00
Hanna Reitz
0423f75351 qcow2: Add errp to rebuild_refcount_structure()
Instead of fprint()-ing error messages in rebuild_refcount_structure()
and its rebuild_refcounts_write_refblocks() helper, pass them through an
Error object to qcow2_check_refcounts() (which will then print it).

Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220405134652.19278-4-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2022-04-20 12:09:17 +02:00
Hanna Reitz
a8c07ec287 qcow2: Improve refcount structure rebuilding
When rebuilding the refcount structures (when qemu-img check -r found
errors with refcount = 0, but reference count > 0), the new refcount
table defaults to being put at the image file end[1].  There is no good
reason for that except that it means we will not have to rewrite any
refblocks we already wrote to disk.

Changing the code to rewrite those refblocks is not too difficult,
though, so let us do that.  That is beneficial for images on block
devices, where we cannot really write beyond the end of the image file.

Use this opportunity to add extensive comments to the code, and refactor
it a bit, getting rid of the backwards-jumping goto.

[1] Unless there is something allocated in the area pointed to by the
    last refblock, so we have to write that refblock.  In that case, we
    try to put the reftable in there.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1519071
Closes: https://gitlab.com/qemu-project/qemu/-/issues/941
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220405134652.19278-2-hreitz@redhat.com>
2022-04-20 10:14:28 +02:00
Marc-André Lureau
0f9668e0c1 Remove qemu-common.h include from most units
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-33-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 14:31:55 +02:00
Marc-André Lureau
89fc45d5c6 include: move qemu_get_vm_name() to sysemu.h
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-26-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 14:31:43 +02:00
Marc-André Lureau
8e3b0cbb72 Replace qemu_real_host_page variables with inlined functions
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.

This avoids the need for a constructor initialization too.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06 10:50:38 +02:00
Hanna Reitz
b1e1af394d block/stream: Drain subtree around graph change
When the stream block job cuts out the nodes between top and base in
stream_prepare(), it does not drain the subtree manually; it fetches the
base node, and tries to insert it as the top node's backing node with
bdrv_set_backing_hd().  bdrv_set_backing_hd() however will drain, and so
the actual base node might change (because the base node is actually not
part of the stream job) before the old base node passed to
bdrv_set_backing_hd() is installed.

This has two implications:

First, the stream job does not keep a strong reference to the base node.
Therefore, if it is deleted in bdrv_set_backing_hd()'s drain (e.g.
because some other block job is drained to finish), we will get a
use-after-free.  We should keep a strong reference to that node.

Second, even with such a strong reference, the problem remains that the
base node might change before bdrv_set_backing_hd() actually runs and as
a result the wrong base node is installed.

Both effects can be seen in 030's TestParallelOps.test_overlapping_5()
case, which has five nodes, and simultaneously streams from the middle
node to the top node, and commits the middle node down to the base node.
As it is, this will sometimes crash, namely when we encounter the
above-described use-after-free.

Taking a strong reference to the base node, we no longer get a crash,
but the resuling block graph is less than ideal: The expected result is
obviously that all middle nodes are cut out and the base node is the
immediate backing child of the top node.  However, if stream_prepare()
takes a strong reference to its base node (the middle node), and then
the commit job finishes in bdrv_set_backing_hd(), supposedly dropping
that middle node, the stream job will just reinstall it again.

Therefore, we need to keep the whole subtree drained in
stream_prepare(), so that the graph modification it performs is
effectively atomic, i.e. that the base node it fetches is still the base
node when bdrv_set_backing_hd() sets it as the top node's backing node.

Verify this by asserting in said 030's test case that the base node is
always the top node's immediate backing child when both jobs are done.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220324140907.17192-1-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Vladimir Sementsov-Ogievskiy <v.sementsov-og@mail.ru>
2022-03-29 16:30:55 +02:00
Philippe Mathieu-Daudé
3f1db95917 block: Fix misleading hexadecimal format
"0x%u" format is very misleading, replace by "0x%x".

Found running:

  $ git grep -E '0x%[0-9]*([lL]*|" ?PRI)[dDuU]' block/

Inspired-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-id: 20220323114718.58714-2-philippe.mathieu.daude@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-03-24 10:38:42 +00:00
Peter Maydell
04ddcda6a2 Fixes and cleanups for 7.0
Hi,
 
 A collection of fixes & cleanup patches that should be safe for 7.0 inclusion.
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Merge tag 'fixes-pull-request' of gitlab.com:marcandre.lureau/qemu into staging

Fixes and cleanups for 7.0

Hi,

A collection of fixes & cleanup patches that should be safe for 7.0 inclusion.

# gpg: Signature made Tue 22 Mar 2022 12:11:30 GMT
# gpg:                using RSA key 87A9BD933F87C606D276F62DDAE8E10975969CE5
# gpg:                issuer "marcandre.lureau@redhat.com"
# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg:                 aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276  F62D DAE8 E109 7596 9CE5

* tag 'fixes-pull-request' of gitlab.com:marcandre.lureau/qemu: (21 commits)
  qapi: remove needless include
  Remove trailing ; after G_DEFINE_AUTO macro
  tests: remove needless include
  error: use GLib to remember the program name
  qga: remove bswap.h include
  qapi: remove needless include
  meson: fix CONFIG_ATOMIC128 check
  meson: move int128 checks from configure
  qapi: remove needless include
  util: remove the net/net.h dependency
  util: remove needless includes
  scripts/modinfo-collect: remove unused/dead code
  Move HOST_LONG_BITS to compiler.h
  Simplify HOST_LONG_BITS
  compiler.h: replace QEMU_SENTINEL with G_GNUC_NULL_TERMINATED
  compiler.h: replace QEMU_WARN_UNUSED_RESULT with G_GNUC_WARN_UNUSED_RESULT
  Replace GCC_FMT_ATTR with G_GNUC_PRINTF
  Drop qemu_foo() socket API wrapper
  m68k/nios2-semi: fix gettimeofday() result check
  vl: typo fix in a comment
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-03-22 18:43:03 +00:00
Peter Maydell
9d36d5f7e0 Block patches for 7.0-rc1:
- iotest fixes:
   - Fix some iotests for riscv targets
   - Use GNU sed in more places where required
   - Meson-related fixes (i.e. to print errors when they occur)
   - Have qemu-img calls (from Python tests) generally raise nicely
     formattable exceptions on errors
   - Fix iotest 207
 - Allow RBD images to be growable by writing zeroes past the end of
   file, fixing qcow2 on rbd
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Merge tag 'pull-block-2022-03-22' of https://gitlab.com/hreitz/qemu into staging

Block patches for 7.0-rc1:
- iotest fixes:
  - Fix some iotests for riscv targets
  - Use GNU sed in more places where required
  - Meson-related fixes (i.e. to print errors when they occur)
  - Have qemu-img calls (from Python tests) generally raise nicely
    formattable exceptions on errors
  - Fix iotest 207
- Allow RBD images to be growable by writing zeroes past the end of
  file, fixing qcow2 on rbd

# gpg: Signature made Tue 22 Mar 2022 11:51:10 GMT
# gpg:                using RSA key CB62D7A0EE3829E45F004D34A1FA40D098019CDF
# gpg:                issuer "hreitz@redhat.com"
# gpg: Good signature from "Hanna Reitz <hreitz@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: CB62 D7A0 EE38 29E4 5F00  4D34 A1FA 40D0 9801 9CDF

* tag 'pull-block-2022-03-22' of https://gitlab.com/hreitz/qemu: (25 commits)
  iotests/207: Filter host fingerprint
  iotests.py: Filters for VM.run_job()
  iotests: make qemu_img_log and img_info_log raise on error
  iotests: remove qemu_img_pipe_and_status()
  iotests: replace qemu_img_log('create', ...) calls
  iotests: use qemu_img() in has_working_luks()
  iotests: remove remaining calls to qemu_img_pipe()
  iotests/149: Remove qemu_img_pipe() call
  iotests: replace unchecked calls to qemu_img_pipe()
  iotests: change supports_quorum to use qemu_img
  iotests: add qemu_img_map() function
  iotests/remove-bitmap-from-backing: use qemu_img_info()
  iotests: add qemu_img_info()
  iotests: use qemu_img_json() when applicable
  iotests: add qemu_img_json()
  iotests: fortify compare_images() against crashes
  iotests: make qemu_img raise on non-zero rc by default
  iotests: Remove explicit checks for qemu_img() == 0
  python/utils: add VerboseProcessError
  python/utils: add add_visual_margin() text decoration utility
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-03-22 12:44:11 +00:00
Marc-André Lureau
c08401793a compiler.h: replace QEMU_WARN_UNUSED_RESULT with G_GNUC_WARN_UNUSED_RESULT
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-22 14:40:51 +04:00
Marc-André Lureau
9edc6313da Replace GCC_FMT_ATTR with G_GNUC_PRINTF
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
2022-03-22 14:40:51 +04:00
Stefano Garzarella
cc5387a544 block/rbd: fix write zeroes with growing images
Commit d24f80234b ("block/rbd: increase dynamically the image size")
added a workaround to support growing images (eg. qcow2), resizing
the image before write operations that exceed the current size.

We recently added support for write zeroes and without the
workaround we can have problems with qcow2.

So let's move the resize into qemu_rbd_start_co() and do it when
the command is RBD_AIO_WRITE or RBD_AIO_WRITE_ZEROES.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2020993
Fixes: c56ac27d2a ("block/rbd: add write zeroes support")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20220317162638.41192-1-sgarzare@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-22 09:40:54 +01:00
Rao Lei
6690302b84 block/nbd.c: Fixed IO request coroutine not being wakeup when kill NBD server
During the IO stress test, the IO request coroutine has a probability that is
can't be awakened when the NBD server is killed.

The GDB stack is as follows:
(gdb) bt
0  0x00007f2ff990cbf6 in __ppoll (fds=0x55575de85000, nfds=1, timeout=<optimized out>, sigmask=0x0) at ../sysdeps/unix/sysv/linux/ppoll.c:44
1  0x000055575c302e7c in qemu_poll_ns (fds=0x55575de85000, nfds=1, timeout=599999603140) at ../util/qemu-timer.c:348
2  0x000055575c2d3c34 in fdmon_poll_wait (ctx=0x55575dc480f0, ready_list=0x7ffd9dd1dae0, timeout=599999603140) at ../util/fdmon-poll.c:80
3  0x000055575c2d350d in aio_poll (ctx=0x55575dc480f0, blocking=true) at ../util/aio-posix.c:655
4  0x000055575c16eabd in bdrv_do_drained_begin(bs=0x55575dee7fe0, recursive=false, parent=0x0, ignore_bds_parents=false, poll=true)at ../block/io.c:474
5  0x000055575c16eba6 in bdrv_drained_begin (bs=0x55575dee7fe0) at ../block/io.c:480
6  0x000055575c1aff33 in quorum_del_child (bs=0x55575dee7fe0, child=0x55575dcea690, errp=0x7ffd9dd1dd08) at ../block/quorum.c:1130
7  0x000055575c14239b in bdrv_del_child (parent_bs=0x55575dee7fe0, child=0x55575dcea690, errp=0x7ffd9dd1dd08) at ../block.c:7705
8  0x000055575c12da28 in qmp_x_blockdev_change(parent=0x55575df404c0 "colo-disk0", has_child=true, child=0x55575de867f0 "children.1", has_node=false, no   de=0x0, errp=0x7ffd9dd1dd08) at ../blockdev.c:3676
9  0x000055575c258435 in qmp_marshal_x_blockdev_change (args=0x7f2fec008190, ret=0x7f2ff7b0bd98, errp=0x7f2ff7b0bd90) at qapi/qapi-commands-block-core.c   :1675
10 0x000055575c2c6201 in do_qmp_dispatch_bh (opaque=0x7f2ff7b0be30) at ../qapi/qmp-dispatch.c:129
11 0x000055575c2ebb1c in aio_bh_call (bh=0x55575dc429c0) at ../util/async.c:141
12 0x000055575c2ebc2a in aio_bh_poll (ctx=0x55575dc480f0) at ../util/async.c:169
13 0x000055575c2d2d96 in aio_dispatch (ctx=0x55575dc480f0) at ../util/aio-posix.c:415
14 0x000055575c2ec07f in aio_ctx_dispatch (source=0x55575dc480f0, callback=0x0, user_data=0x0) at ../util/async.c:311
15 0x00007f2ff9e7cfbd in g_main_context_dispatch () at /lib/x86_64-linux-gnu/libglib-2.0.so.0
16 0x000055575c2fd581 in glib_pollfds_poll () at ../util/main-loop.c:232
17 0x000055575c2fd5ff in os_host_main_loop_wait (timeout=0) at ../util/main-loop.c:255
18 0x000055575c2fd710 in main_loop_wait (nonblocking=0) at ../util/main-loop.c:531
19 0x000055575bfa7588 in qemu_main_loop () at ../softmmu/runstate.c:726
20 0x000055575bbee57a in main (argc=60, argv=0x7ffd9dd1e0e8, envp=0x7ffd9dd1e2d0) at ../softmmu/main.c:50

(gdb) qemu coroutine 0x55575e16aac0
0  0x000055575c2ee7dc in qemu_coroutine_switch (from_=0x55575e16aac0, to_=0x7f2ff830fba0, action=COROUTINE_YIELD) at ../util/coroutine-ucontext.c:302
1  0x000055575c2fe2a9 in qemu_coroutine_yield () at ../util/qemu-coroutine.c:195
2  0x000055575c2fe93c in qemu_co_queue_wait_impl (queue=0x55575dc46170, lock=0x7f2b32ad9850) at ../util/qemu-coroutine-lock.c:56
3  0x000055575c17ddfb in nbd_co_send_request (bs=0x55575ebfaf20, request=0x7f2b32ad9920, qiov=0x55575dfc15d8) at ../block/nbd.c:478
4  0x000055575c17f931 in nbd_co_request (bs=0x55575ebfaf20, request=0x7f2b32ad9920, write_qiov=0x55575dfc15d8) at ../block/nbd.c:1182
5  0x000055575c17fe14 in nbd_client_co_pwritev (bs=0x55575ebfaf20, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, flags=0) at ../block/nbd.c:1284
6  0x000055575c170d25 in bdrv_driver_pwritev (bs=0x55575ebfaf20, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, qiov_offset=0, flags=0)
    at ../block/io.c:1264
7  0x000055575c1733b4 in bdrv_aligned_pwritev
    (child=0x55575dff6890, req=0x7f2b32ad9ad0, offset=403487858688, bytes=4538368, align=1, qiov=0x55575dfc15d8, qiov_offset=0, flags=0) at ../block/io.c:2126
8  0x000055575c173c67 in bdrv_co_pwritev_part (child=0x55575dff6890, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, qiov_offset=0, flags=0)
    at ../block/io.c:2314
9  0x000055575c17391b in bdrv_co_pwritev (child=0x55575dff6890, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, flags=0) at ../block/io.c:2233
10 0x000055575c1ee506 in replication_co_writev (bs=0x55575e9824f0, sector_num=788062224, remaining_sectors=8864, qiov=0x55575dfc15d8, flags=0)
    at ../block/replication.c:270
11 0x000055575c170eed in bdrv_driver_pwritev (bs=0x55575e9824f0, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, qiov_offset=0, flags=0)
    at ../block/io.c:1297
12 0x000055575c1733b4 in bdrv_aligned_pwritev
    (child=0x55575dcea690, req=0x7f2b32ad9e00, offset=403487858688, bytes=4538368, align=512, qiov=0x55575dfc15d8, qiov_offset=0, flags=0)
    at ../block/io.c:2126
13 0x000055575c173c67 in bdrv_co_pwritev_part (child=0x55575dcea690, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, qiov_offset=0, flags=0)
    at ../block/io.c:2314
14 0x000055575c17391b in bdrv_co_pwritev (child=0x55575dcea690, offset=403487858688, bytes=4538368, qiov=0x55575dfc15d8, flags=0) at ../block/io.c:2233
15 0x000055575c1aeffa in write_quorum_entry (opaque=0x7f2fddaf8c50) at ../block/quorum.c:699
16 0x000055575c2ee4db in coroutine_trampoline (i0=1578543808, i1=21847) at ../util/coroutine-ucontext.c:173
17 0x00007f2ff9855660 in __start_context () at ../sysdeps/unix/sysv/linux/x86_64/__start_context.S:91

When we do failover in COLO mode, QEMU will hang while it is waiting for
the in-flight IO. From the call trace, we can see the IO request coroutine
has yielded in nbd_co_send_request(). When we kill the NBD server, it will never
be wake up. Actually, when we do IO stress test, it will have a lot of
requests in free_sema queue. When the NBD server is killed, current
MAX_NBD_REQUESTS finishes with errors but they wake up at most
MAX_NBD_REQEUSTS from the queue. So, let's move qemu_co_queue_next out
to fix this issue.

Signed-off-by: Lei Rao <lei.rao@intel.com>
Message-Id: <20220309074844.275450-1-lei.rao@intel.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-03-21 15:21:09 -05:00
Philippe Mathieu-Daudé
aa44d3f6b8 block/file-posix: Remove a deprecation warning on macOS 12
When building on macOS 12 we get:

  block/file-posix.c:3335:18: warning: 'IOMasterPort' is deprecated: first deprecated in macOS 12.0 [-Wdeprecated-declarations]
      kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
                   ^~~~~~~~~~~~
                   IOMainPort

Replace by IOMainPort, redefining it to IOMasterPort if not available.

Suggested-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed by: Cameron Esfahani <dirty@apple.com>
Reviewed-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Tested-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2022-03-15 13:36:33 +01:00
Peter Maydell
fdee2c9692 nbd patches for 2022-03-07
- Dan Berrange: Allow qemu-nbd to support TLS over Unix sockets
 - Eric Blake: Minor cleanups related to 64-bit block operations
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCAAdFiEEccLMIrHEYCkn0vOqp6FrSiUnQ2oFAmImtE8ACgkQp6FrSiUn
 Q2ovmgf/aksDqf2eNcahs++fez+8Qi9ll5OY/qGyjnzBgsatYKjrK+xF7OnjoJox
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 t0w5L9yCxBrRpY1burz30b77J0WMCw==
 =C8Dd
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2022-03-07' into staging

nbd patches for 2022-03-07

- Dan Berrange: Allow qemu-nbd to support TLS over Unix sockets
- Eric Blake: Minor cleanups related to 64-bit block operations

# gpg: Signature made Tue 08 Mar 2022 01:41:35 GMT
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]
# Primary key fingerprint: 71C2 CC22 B1C4 6029 27D2  F3AA A7A1 6B4A 2527 436A

* remotes/ericb/tags/pull-nbd-2022-03-07:
  qemu-io: Allow larger write zeroes under no fallback
  qemu-io: Utilize 64-bit status during map
  nbd/server: Minor cleanups
  tests/qemu-iotests: validate NBD TLS with UNIX sockets and PSK
  tests/qemu-iotests: validate NBD TLS with UNIX sockets
  tests/qemu-iotests: validate NBD TLS with hostname mismatch
  tests/qemu-iotests: convert NBD TLS test to use standard filters
  tests/qemu-iotests: introduce filter for qemu-nbd export list
  tests/qemu-iotests: expand _filter_nbd rules
  tests/qemu-iotests: add QEMU_IOTESTS_REGEN=1 to update reference file
  block/nbd: don't restrict TLS usage to IP sockets
  qemu-nbd: add --tls-hostname option for TLS certificate validation
  block/nbd: support override of hostname for TLS certificate validation
  block: pass desired TLS hostname through from block driver client
  crypto: mandate a hostname when checking x509 creds on a client

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-03-09 11:38:29 +00:00
Peter Maydell
9740b907a5 target-arm queue:
* cleanups of qemu_oom_check() and qemu_memalign()
  * target/arm/translate-neon: UNDEF if VLD1/VST1 stride bits are non-zero
  * target/arm/translate-neon: Simplify align field check for VLD3
  * GICv3 ITS: add more trace events
  * GICv3 ITS: implement 8-byte accesses properly
  * GICv3: fix minor issues with some trace/log messages
  * ui/cocoa: Use the standard about panel
  * target/arm: Provide cpu property for controling FEAT_LPA2
  * hw/arm/virt: Disable LPA2 for -machine virt-6.2
 -----BEGIN PGP SIGNATURE-----
 
 iQJNBAABCAA3FiEE4aXFk81BneKOgxXPPCUl7RQ2DN4FAmImNs4ZHHBldGVyLm1h
 eWRlbGxAbGluYXJvLm9yZwAKCRA8JSXtFDYM3q87D/0cMQeF00uVRNqftrQg2SDI
 txJIG2QYUOPMCDfGWlGTfXv2TUc5y3XwA77C9vTcJcIWJlZ30DUa95DNYqA0BbOH
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 lnusB8MR1sESoqYdPZsAfQ==
 =ix0J
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20220307' into staging

target-arm queue:
 * cleanups of qemu_oom_check() and qemu_memalign()
 * target/arm/translate-neon: UNDEF if VLD1/VST1 stride bits are non-zero
 * target/arm/translate-neon: Simplify align field check for VLD3
 * GICv3 ITS: add more trace events
 * GICv3 ITS: implement 8-byte accesses properly
 * GICv3: fix minor issues with some trace/log messages
 * ui/cocoa: Use the standard about panel
 * target/arm: Provide cpu property for controling FEAT_LPA2
 * hw/arm/virt: Disable LPA2 for -machine virt-6.2

# gpg: Signature made Mon 07 Mar 2022 16:46:06 GMT
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20220307:
  hw/arm/virt: Disable LPA2 for -machine virt-6.2
  target/arm: Provide cpu property for controling FEAT_LPA2
  ui/cocoa: Use the standard about panel
  hw/intc/arm_gicv3_cpuif: Fix register names in ICV_HPPIR read trace event
  hw/intc/arm_gicv3: Fix missing spaces in error log messages
  hw/intc/arm_gicv3: Specify valid and impl in MemoryRegionOps
  hw/intc/arm_gicv3_its: Add trace events for table reads and writes
  hw/intc/arm_gicv3_its: Add trace events for commands
  target/arm/translate-neon: Simplify align field check for VLD3
  target/arm/translate-neon: UNDEF if VLD1/VST1 stride bits are non-zero
  osdep: Move memalign-related functions to their own header
  util: Put qemu_vfree() in memalign.c
  util: Use meson checks for valloc() and memalign() presence
  util: Share qemu_try_memalign() implementation between POSIX and Windows
  meson.build: Don't misdetect posix_memalign() on Windows
  util: Return valid allocation for qemu_try_memalign() with zero size
  util: Unify implementations of qemu_memalign()
  util: Make qemu_oom_check() a static function

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2022-03-08 15:26:10 +00:00
Daniel P. Berrangé
e8ae8b1a75 block/nbd: don't restrict TLS usage to IP sockets
The TLS usage for NBD was restricted to IP sockets because validating
x509 certificates requires knowledge of the hostname that the client
is connecting to.

TLS does not have to use x509 certificates though, as PSK (pre-shared
keys) provide an alternative credential option. These have no
requirement for a hostname and can thus be trivially used for UNIX
sockets.

Furthermore, with the ability to overide the default hostname for
TLS validation in the previous patch, it is now also valid to want
to use x509 certificates with FD passing and UNIX sockets.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220304193610.3293146-6-berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-03-07 15:58:42 -06:00
Daniel P. Berrangé
a0cd6d2972 block/nbd: support override of hostname for TLS certificate validation
When connecting to an NBD server with TLS and x509 credentials,
the client must validate the hostname it uses for the connection,
against that published in the server's certificate. If the client
is tunnelling its connection over some other channel, however, the
hostname it uses may not match the info reported in the server's
certificate. In such a case, the user needs to explicitly set an
override for the hostname to use for certificate validation.

This is achieved by adding a 'tls-hostname' property to the NBD
block driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220304193610.3293146-4-berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-03-07 15:58:42 -06:00
Daniel P. Berrangé
046f98d075 block: pass desired TLS hostname through from block driver client
In

  commit a71d597b98
  Author: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
  Date:   Thu Jun 10 13:08:00 2021 +0300

    block/nbd: reuse nbd_co_do_establish_connection() in nbd_open()

the use of the 'hostname' field from the BDRVNBDState struct was
lost, and 'nbd_connect' just hardcoded it to match the IP socket
address. This was a harmless bug at the time since we block use
with anything other than IP sockets.

Shortly though, we want to allow the caller to override the hostname
used in the TLS certificate checks. This is to allow for TLS
when doing port forwarding or tunneling. Thus we need to reinstate
the passing along of the 'hostname'.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20220304193610.3293146-3-berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-03-07 15:58:42 -06:00
Peter Maydell
5df022cf2e osdep: Move memalign-related functions to their own header
Move the various memalign-related functions out of osdep.h and into
their own header, which we include only where they are used.
While we're doing this, add some brief documentation comments.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20220226180723.1706285-10-peter.maydell@linaro.org
2022-03-07 13:16:49 +00:00
Vladimir Sementsov-Ogievskiy
af5bcd775f block: copy-before-write: realize snapshot-access API
Current scheme of image fleecing looks like this:

[guest]                    [NBD export]
  |                              |
  |root                          | root
  v                              v
[copy-before-write] -----> [temp.qcow2]
  |                 target  |
  |file                     |backing
  v                         |
[active disk] <-------------+

 - On guest writes copy-before-write filter copies old data from active
   disk to temp.qcow2. So fleecing client (NBD export) when reads
   changed regions from temp.qcow2 image and unchanged from active disk
   through backing link.

This patch makes possible new image fleecing scheme:

[guest]                   [NBD export]
   |                            |
   | root                       | root
   v                 file       v
[copy-before-write]<------[snapshot-access]
   |           |
   | file      | target
   v           v
[active-disk] [temp.img]

 - copy-before-write does CBW operations and also provides
   snapshot-access API. The API may be accessed through
   snapshot-access driver.

Benefits of new scheme:

1. Access control: if remote client try to read data that not covered
   by original dirty bitmap used on copy-before-write open, client gets
   -EACCES.

2. Discard support: if remote client do DISCARD, this additionally to
   discarding data in temp.img informs block-copy process to not copy
   these clusters. Next read from discarded area will return -EACCES.
   This is significant thing: when fleecing user reads data that was
   not yet copied to temp.img, we can avoid copying it on further guest
   write.

3. Synchronisation between client reads and block-copy write is more
   efficient. In old scheme we just rely on BDRV_REQ_SERIALISING flag
   used for writes to temp.qcow2. New scheme is less blocking:
     - fleecing reads are never blocked: if data region is untouched or
       in-flight, we just read from active-disk, otherwise we read from
       temp.img
     - writes to temp.img are not blocked by fleecing reads
     - still, guest writes of-course are blocked by in-flight fleecing
       reads, that currently read from active-disk - it's the minimum
       necessary blocking

4. Temporary image may be of any format, as we don't rely on backing
   feature.

5. Permission relation are simplified. With old scheme we have to share
   write permission on target child of copy-before-write, otherwise
   backing link conflicts with copy-before-write file child write
   permissions. With new scheme we don't have backing link, and
   copy-before-write node may have unshared access to temporary node.
   (Not realized in this commit, will be in future).

6. Having control on fleecing reads we'll be able to implement
   alternative behavior on failed copy-before-write operations.
   Currently we just break guest request (that's a historical behavior
   of backup). But in some scenarios it's a bad behavior: better
   is to drop the backup as failed but don't break guest request.
   With new scheme we can simply unset some bits in a bitmap on CBW
   failure and further fleecing reads will -EACCES, or something like
   this. (Not implemented in this commit, will be in future)
   Additional application for this is implementing timeout for CBW
   operations.

Iotest 257 output is updated, as two more bitmaps now live in
copy-before-write filter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20220303194349.2304213-13-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:31 +01:00
Vladimir Sementsov-Ogievskiy
1c14eaabdb block: introduce snapshot-access block driver
The new block driver simply utilizes snapshot-access API of underlying
block node.

In further patches we want to use it like this:

[guest]                   [NBD export]
   |                            |
   | root                       | root
   v                 file       v
[copy-before-write]<------[snapshot-access]
   |           |
   | file      | target
   v           v
[active-disk] [temp.img]

This way, NBD client will be able to read snapshotted state of active
disk, when active disk is continued to be written by guest. This is
known as "fleecing", and currently uses another scheme based on qcow2
temporary image which backing file is active-disk. New scheme comes
with benefits - see next commit.

The other possible application is exporting internal snapshots of
qcow2, like this:

[guest]          [NBD export]
   |                  |
   | root             | root
   v       file       v
[qcow2]<---------[snapshot-access]

For this, we'll need to implement snapshot-access API handlers in
qcow2 driver, and improve snapshot-access block driver (and API) to
make it possible to select snapshot by name. Another thing to improve
is size of snapshot. Now for simplicity we just use size of bs->file,
which is OK for backup, but for qcow2 snapshots export we'll need to
imporve snapshot-access API to get size of snapshot.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20220303194349.2304213-12-vsementsov@virtuozzo.com>
[hreitz: Rebased on block GS/IO split]
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:31 +01:00
Vladimir Sementsov-Ogievskiy
ce14f3b407 block/io: introduce block driver snapshot-access API
Add new block driver handlers and corresponding generic wrappers.
It will be used to allow copy-before-write filter to provide
reach fleecing interface in further commit.

In future this approach may be used to allow reading qcow2 internal
snapshots, for example to export them through NBD.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-11-vsementsov@virtuozzo.com>
[hreitz: Rebased on block GS/IO split]
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:31 +01:00
Vladimir Sementsov-Ogievskiy
3b7ca26bdf block/reqlist: add reqlist_wait_all()
Add function to wait for all intersecting requests.
To be used in the further commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Nikita Lapshin <nikita.lapshin@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-10-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
a6426475a7 block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()
Add a convenient function similar with bdrv_block_status() to get
status of dirty bitmap.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-9-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
84b1e80f67 block/reqlist: reqlist_find_conflict(): use ranges_overlap()
Let's reuse convenient helper.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-8-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
d088e6a48a block: intoduce reqlist
Split intersecting-requests functionality out of block-copy to be
reused in copy-before-write filter.

Note: while being here, fix tiny typo in MAINTAINERS.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-7-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
177541e671 block/block-copy: add block_copy_reset()
Split block_copy_reset() out of block_copy_reset_unallocated() to be
used separately later.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-6-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
5f3a3cd7f0 block/copy-before-write: add bitmap open parameter
This brings "incremental" mode to copy-before-write filter: user can
specify bitmap so that filter will copy only "dirty" areas.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20220303194349.2304213-5-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
1f7252e868 block/block-copy: block_copy_state_new(): add bitmap parameter
This will be used in the following commit to bring "incremental" mode
to copy-before-write filter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-4-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
34ffacb7f4 block/dirty-bitmap: bdrv_merge_dirty_bitmap(): add return value
That simplifies handling failure in existing code and in further new
usage of bdrv_merge_dirty_bitmap().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-3-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
051f66caa2 block/block-copy: move copy_bitmap initialization to block_copy_state_new()
We are going to complicate bitmap initialization in the further
commit. And in future, backup job will be able to work without filter
(when source is immutable), so we'll need same bitmap initialization in
copy-before-write filter and in backup job. So, it's reasonable to do
it in block-copy.

Note that for now cbw_open() is the only caller of
block_copy_state_new().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-2-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:33:30 +01:00
Vladimir Sementsov-Ogievskiy
45e62b464a block: fix preallocate filter: don't do unaligned preallocate requests
There is a bug in handling BDRV_REQ_NO_WAIT flag: we still may wait in
wait_serialising_requests() if request is unaligned. And this is
possible for the only user of this flag (preallocate filter) if
underlying file is unaligned to its request_alignment on start.

So, we have to fix preallocate filter to do only aligned preallocate
requests.

Next, we should fix generic block/io.c somehow. Keeping in mind that
preallocate is the only user of BDRV_REQ_NO_WAIT and that we have to
fix its behavior now, it seems more safe to just assert that we never
use BDRV_REQ_NO_WAIT with unaligned requests and add corresponding
comment. Let's do so.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Message-Id: <20220215121609.38570-1-vsementsov@virtuozzo.com>
[hreitz: Rebased on block GS/IO split]
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:19:20 +01:00
Peter Maydell
b0ea6c98fa block/curl.c: Check error return from curl_easy_setopt()
Coverity points out that we aren't checking the return value
from curl_easy_setopt() for any of the calls to it we make
in block/curl.c.

Some of these options are documented as always succeeding (e.g.
CURLOPT_VERBOSE) but others have documented failure cases (e.g.
CURLOPT_URL).  For consistency we check every call, even the ones
that theoretically cannot fail.

Fixes: Coverity CID 1459336, 1459482, 1460331
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220222152341.850419-3-peter.maydell@linaro.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:19:20 +01:00
Peter Maydell
2ea7dfcd05 block/curl.c: Set error message string if curl_init_state() fails
In curl_open(), the 'out' label assumes that the state->errmsg string
has been set (either by curl_easy_perform() or by manually copying a
string into it); however if curl_init_state() fails we will jump to
that label without setting the string.  Add the missing error string
setup.

(We can't be specific about the cause of failure: the documentation
of curl_easy_init() just says "If this function returns NULL,
something went wrong".)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220222152341.850419-2-peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-03-07 09:19:20 +01:00
Hanna Reitz
78fa41fc67 block/amend: Keep strong reference to BDS
Otherwise, the BDS might be freed while the job is running, which would
cause a use-after-free.

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220304153729.711387-5-hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:26 +01:00
Hanna Reitz
b8ba60067b block/amend: Always call .bdrv_amend_clean()
.bdrv_amend_clean() says block drivers can use it to clean up what was
done in .bdrv_amend_pre_run().  Therefore, it should always be called
after .bdrv_amend_pre_run(), which means we need it to call it in the
JobDriver.free() callback, not in JobDriver.clean().

Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220304153729.711387-3-hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:26 +01:00
Hanna Reitz
4d378bbd83 block: Make bdrv_refresh_limits() non-recursive
bdrv_refresh_limits() recurses down to the node's children.  That does
not seem necessary: When we refresh limits on some node, and then
recurse down and were to change one of its children's BlockLimits, then
that would mean we noticed the changed limits by pure chance.  The fact
that we refresh the parent's limits has nothing to do with it, so the
reason for the change probably happened before this point in time, and
we should have refreshed the limits then.

Consequently, we should actually propagate block limits changes upwards,
not downwards.  That is a separate and pre-existing issue, though, and
so will not be addressed in this patch.

The problem with recursing is that bdrv_refresh_limits() is not atomic.
It begins with zeroing BDS.bl, and only then sets proper, valid limits.
If we do not drain all nodes whose limits are refreshed, then concurrent
I/O requests can encounter invalid request_alignment values and crash
qemu.  Therefore, a recursing bdrv_refresh_limits() requires the whole
subtree to be drained, which is currently not ensured by most callers.

A non-recursive bdrv_refresh_limits() only requires the node in question
to not receive I/O requests, and this is done by most callers in some
way or another:
- bdrv_open_driver() deals with a new node with no parents yet
- bdrv_set_file_or_backing_noperm() acts on a drained node
- bdrv_reopen_commit() acts only on drained nodes
- bdrv_append() should in theory require the node to be drained; in
  practice most callers just lock the AioContext, which should at least
  be enough to prevent concurrent I/O requests from accessing invalid
  limits

So we can resolve the bug by making bdrv_refresh_limits() non-recursive.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1879437
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20220216105355.30729-2-hreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:26 +01:00
Emanuele Giuseppe Esposito
da359909bd block_int-common.h: assertions in the callers of BlockDriver function pointers
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-27-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00