Commit Graph

417 Commits

Author SHA1 Message Date
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
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
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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
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
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
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
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
1581a70ddd block/coroutines: I/O and "I/O or GS" API
block coroutines functions run in different aiocontext, and are
not protected by the BQL. Therefore are I/O.

On the other side, generated_co_wrapper functions use BDRV_POLL_WHILE,
meaning the caller can either be the main loop or a specific iothread.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-25-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00
Emanuele Giuseppe Esposito
967d7905d1 IO_CODE and IO_OR_GS_CODE for block_int I/O API
Mark all I/O functions with IO_CODE, and all "I/O OR GS" with
IO_OR_GS_CODE.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-14-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00
Emanuele Giuseppe Esposito
b4ad82aab1 assertions for block_int global state API
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-13-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00
Emanuele Giuseppe Esposito
384a48fb74 IO_CODE and IO_OR_GS_CODE for block I/O API
Mark all I/O functions with IO_CODE, and all "I/O OR GS" with
IO_OR_GS_CODE.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-6-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00
Emanuele Giuseppe Esposito
f791bf7f93 assertions for block global state API
All the global state (GS) API functions will check that
qemu_in_main_thread() returns true. If not, it means
that the safety of BQL cannot be guaranteed, and
they need to be moved to I/O.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20220303151616.325444-5-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-03-04 18:18:25 +01:00
Hanna Reitz
113b727ce7 block/io: Update BSC only if want_zero is true
We update the block-status cache whenever we get new information from a
bdrv_co_block_status() call to the block driver.  However, if we have
passed want_zero=false to that call, it may flag areas containing zeroes
as data, and so we would update the block-status cache with wrong
information.

Therefore, we should not update the cache with want_zero=false.

Reported-by: Nir Soffer <nsoffer@redhat.com>
Fixes: 0bc329fbb0 ("block: block-status cache for data regions")
Reviewed-by: Nir Soffer <nsoffer@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220118170000.49423-2-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2022-01-28 16:52:40 -06:00
Paolo Bonzini
cc07162953 block: introduce max_hw_iov for use in scsi-generic
Linux limits the size of iovecs to 1024 (UIO_MAXIOV in the kernel
sources, IOV_MAX in POSIX).  Because of this, on some host adapters
requests with many iovecs are rejected with -EINVAL by the
io_submit() or readv()/writev() system calls.

In fact, the same limit applies to SG_IO as well.  To fix both the
EINVAL and the possible performance issues from using fewer iovecs
than allowed by Linux (some HBAs have max_segments as low as 128),
introduce a separate entry in BlockLimits to hold the max_segments
value from sysfs.  This new limit is used only for SG_IO and clamped
to bs->bl.max_iov anyway, just like max_hw_transfer is clamped to
bs->bl.max_transfer.

Reported-by: Halil Pasic <pasic@linux.ibm.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-block@nongnu.org
Cc: qemu-stable@nongnu.org
Fixes: 18473467d5 ("file-posix: try BLKSECTGET on block devices too, do not round to power of 2", 2021-06-25)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210923130436.1187591-1-pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-10-06 10:25:55 +02:00
Vladimir Sementsov-Ogievskiy
6a8f3dbb19 block/io: allow 64bit discard requests
Now that all drivers are updated by the previous commit, we can drop
the last limiter on pdiscard path: INT_MAX in bdrv_co_pdiscard().

Now everything is prepared for implementing incredibly cool and fast
big-discard requests in NBD and qcow2. And any other driver which wants
it of course.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-12-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
39af49c0d7 block: make BlockLimits::max_pdiscard 64bit
We are going to support 64 bit discard requests. Now update the
limit variable. It's absolutely safe. The variable is set in some
drivers, and used in bdrv_co_pdiscard().

Update also max_pdiscard variable in bdrv_co_pdiscard(), so that
bdrv_co_pdiscard() is now prepared for 64bit requests. The remaining
logic including num, offset and bytes variables is already
supporting 64bit requests.

So the only thing that prevents 64 bit requests is limiting
max_pdiscard variable to INT_MAX in bdrv_co_pdiscard().
We'll drop this limitation after updating all block drivers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-10-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
2aaa3f9b33 block/io: allow 64bit write-zeroes requests
Now that all drivers are updated by previous commit, we can drop two
last limiters on write-zeroes path: INT_MAX in
bdrv_co_do_pwrite_zeroes() and bdrv_check_request32() in
bdrv_co_pwritev_part().

Now everything is prepared for implementing incredibly cool and fast
big-write-zeroes in NBD and qcow2. And any other driver which wants it
of course.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-9-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
d544f5d3b1 block: make BlockLimits::max_pwrite_zeroes 64bit
We are going to support 64 bit write-zeroes requests. Now update the
limit variable. It's absolutely safe. The variable is set in some
drivers, and used in bdrv_co_do_pwrite_zeroes().

Update also max_write_zeroes variable in bdrv_co_do_pwrite_zeroes(), so
that bdrv_co_do_pwrite_zeroes() is now prepared to 64bit requests. The
remaining logic including num, offset and bytes variables is already
supporting 64bit requests.

So the only thing that prevents 64 bit requests is limiting
max_write_zeroes variable to INT_MAX in bdrv_co_do_pwrite_zeroes().
We'll drop this limitation after updating all block drivers.

Ah, we also have bdrv_check_request32() in bdrv_co_pwritev_part(). It
will be modified to do bdrv_check_request() for write-zeroes path.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-7-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:32 -05:00
Vladimir Sementsov-Ogievskiy
e75abedab7 block: use int64_t instead of uint64_t in driver write handlers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver write handlers parameters which are already 64bit to
signed type.

While being here, convert also flags parameter to be BdrvRequestFlags.

Now let's consider all callers. Simple

  git grep '\->bdrv_\(aio\|co\)_pwritev\(_part\)\?'

shows that's there three callers of driver function:

 bdrv_driver_pwritev() and bdrv_driver_pwritev_compressed() in
 block/io.c, both pass int64_t, checked by bdrv_check_qiov_request() to
 be non-negative.

 qcow2_save_vmstate() does bdrv_check_qiov_request().

Still, the functions may be called directly, not only by drv->...
Let's check:

git grep '\.bdrv_\(aio\|co\)_pwritev\(_part\)\?\s*=' | \
awk '{print $4}' | sed 's/,//' | sed 's/&//' | sort | uniq | \
while read func; do git grep "$func(" | \
grep -v "$func(BlockDriverState"; done

shows several callers:

qcow2:
  qcow2_co_truncate() write at most up to @offset, which is checked in
    generic qcow2_co_truncate() by bdrv_check_request().
  qcow2_co_pwritev_compressed_task() pass the request (or part of the
    request) that already went through normal write path, so it should
    be OK

qcow:
  qcow_co_pwritev_compressed() pass int64_t, it's updated by this patch

quorum:
  quorum_co_pwrite_zeroes() pass int64_t and int - OK

throttle:
  throttle_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

vmdk:
  vmdk_co_pwritev_compressed() pass int64_t, it's updated by this
  patch

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210903102807.27127-5-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:31 -05:00
Vladimir Sementsov-Ogievskiy
558902cc3d qcow2: check request on vmstate save/load path
We modify the request by adding an offset to vmstate. Let's check the
modified request. It will help us to safely move .bdrv_co_preadv_part
and .bdrv_co_pwritev_part to int64_t type of offset and bytes.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-3-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:31 -05:00
Vladimir Sementsov-Ogievskiy
b984b2968b block/io: bring request check to bdrv_co_(read,write)v_vmstate
Only qcow2 driver supports vmstate.
In qcow2 these requests go through .bdrv_co_p{read,write}v_part
handlers.

So, let's do our basic check for the request on vmstate generic
handlers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210903102807.27127-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-09-29 13:46:31 -05:00
Hanna Reitz
0bc329fbb0 block: block-status cache for data regions
As we have attempted before
(https://lists.gnu.org/archive/html/qemu-devel/2019-01/msg06451.html,
"file-posix: Cache lseek result for data regions";
https://lists.nongnu.org/archive/html/qemu-block/2021-02/msg00934.html,
"file-posix: Cache next hole"), this patch seeks to reduce the number of
SEEK_DATA/HOLE operations the file-posix driver has to perform.  The
main difference is that this time it is implemented as part of the
general block layer code.

The problem we face is that on some filesystems or in some
circumstances, SEEK_DATA/HOLE is unreasonably slow.  Given the
implementation is outside of qemu, there is little we can do about its
performance.

We have already introduced the want_zero parameter to
bdrv_co_block_status() to reduce the number of SEEK_DATA/HOLE calls
unless we really want zero information; but sometimes we do want that
information, because for files that consist largely of zero areas,
special-casing those areas can give large performance boosts.  So the
real problem is with files that consist largely of data, so that
inquiring the block status does not gain us much performance, but where
such an inquiry itself takes a lot of time.

To address this, we want to cache data regions.  Most of the time, when
bad performance is reported, it is in places where the image is iterated
over from start to end (qemu-img convert or the mirror job), so a simple
yet effective solution is to cache only the current data region.

(Note that only caching data regions but not zero regions means that
returning false information from the cache is not catastrophic: Treating
zeroes as data is fine.  While we try to invalidate the cache on zero
writes and discards, such incongruences may still occur when there are
other processes writing to the image.)

We only use the cache for nodes without children (i.e. protocol nodes),
because that is where the problem is: Drivers that rely on block-status
implementations outside of qemu (e.g. SEEK_DATA/HOLE).

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/307
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20210812084148.14458-3-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[hreitz: Added `local_file == bs` assertion, as suggested by Vladimir]
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2021-09-15 15:54:06 +02:00
Kevin Wolf
87ab880252 block: Fix in_flight leak in request padding error path
When bdrv_pad_request() fails in bdrv_co_preadv_part(), bs->in_flight
has been increased, but is never decreased again. This leads to a hang
when trying to drain the block node.

This bug was observed with Windows guests which issue a request that
fully uses IOV_MAX during installation, so that when padding is
necessary (O_DIRECT with a 4k sector size block device on the host),
adding another entry causes failure.

Call bdrv_dec_in_flight() to fix this. There is a larger problem to
solve here because this request shouldn't even fail, but Windows doesn't
seem to care and with this minimal fix the installation succeeds. So
given that we're already in freeze, let's take this minimal fix for 6.1.

Fixes: 98ca45494f
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1972079
Reported-by: Qing Wang <qinwang@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210727154923.91067-1-kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-08-03 15:43:30 +02:00
Akihiko Odaki
9f460c64e1 block/io: Merge discard request alignments
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-id: 20210705130458.97642-3-akihiko.odaki@gmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2021-07-06 14:28:55 +01:00
Eric Blake
97efa8698e block: Move read-only check during truncation earlier
No need to start a tracked request that will always fail.  The choice
to check read-only after bdrv_inc_in_flight() predates 1bc5f09f2e
(block: Use tracked request for truncate), but waiting for serializing
requests can make the effect more noticeable.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210609163034.997943-1-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-29 16:51:00 +02:00
Paolo Bonzini
24b36e9813 block: add max_hw_transfer to BlockLimits
For block host devices, I/O can happen through either the kernel file
descriptor I/O system calls (preadv/pwritev, io_submit, io_uring)
or the SCSI passthrough ioctl SG_IO.

In the latter case, the size of each transfer can be limited by the
HBA, while for file descriptor I/O the kernel is able to split and
merge I/O in smaller pieces as needed.  Applying the HBA limits to
file descriptor I/O results in more system calls and suboptimal
performance, so this patch splits the max_transfer limit in two:
max_transfer remains valid and is used in general, while max_hw_transfer
is limited to the maximum hardware size.  max_hw_transfer can then be
included by the scsi-generic driver in the block limits page, to ensure
that the stricter hardware limit is used.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-06-25 10:54:13 +02:00
Vladimir Sementsov-Ogievskiy
307261b243 block: consistently use bdrv_is_read_only()
It's better to use accessor function instead of bs->read_only directly.
In some places use bdrv_is_writable() instead of
checking both BDRV_O_RDWR set and BDRV_O_INACTIVE not set.

In bdrv_open_common() it's a bit strange to add one more variable, but
we are going to drop bs->read_only in the next patch, so new ro local
variable substitutes it here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210527154056.70294-2-vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-06-02 14:23:20 +02:00
Vladimir Sementsov-Ogievskiy
ad578c56d5 block: drop write notifiers
They are unused now.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210506090621.11848-3-vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2021-05-14 16:14:10 +02:00
Vladimir Sementsov-Ogievskiy
94783301b8 block/write-threshold: don't use write notifiers
write-notifiers are used only for write-threshold. New code for such
purpose should create filters.

Let's better special-case write-threshold and drop write notifiers at
all. (Actually, write-threshold is special-cased anyway, as the only
user of write-notifiers)

So, create a new direct interface for bdrv_co_write_req_prepare() and
drop all write-notifier related logic from write-threshold.c.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210506090621.11848-2-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
[mreitz: Adjusted comment as per Eric's suggestion]
Signed-off-by: Max Reitz <mreitz@redhat.com>
2021-05-14 16:14:10 +02:00
Vladimir Sementsov-Ogievskiy
1e4c797c75 block: make bdrv_refresh_limits() to be a transaction action
To be used in further commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210428151804.439460-28-vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-04-30 12:27:48 +02:00
Vladimir Sementsov-Ogievskiy
bd54669a4a block: add new BlockDriver handler: bdrv_cancel_in_flight
It will be used to stop retrying NBD requests on mirror cancel.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210205163720.887197-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-12 09:45:18 -06:00
Vladimir Sementsov-Ogievskiy
a5215b8fdf block/io: use int64_t bytes in copy_range
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert now copy_range parameters which are already 64bit to signed
type.

It's safe as we don't work with requests overflowing BDRV_MAX_LENGTH
(which is less than INT64_MAX), and do check the requests in
bdrv_co_copy_range_internal() (by bdrv_check_request32(), which calls
bdrv_check_request()).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-17-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:17:12 -06:00
Vladimir Sementsov-Ogievskiy
e9e52efdc5 block/io: support int64_t bytes in read/write wrappers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

Now, since bdrv_co_preadv_part() and bdrv_co_pwritev_part() have been
updated, update all their wrappers.

For all of them type of 'bytes' is widening, so callers are safe. We
have update request_fn in blkverify.c simultaneously. Still it's just a
pointer to one of bdrv_co_pwritev() or bdrv_co_preadv(), and type is
widening for callers of the request_fn anyway.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-16-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: grammar tweak]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:17:12 -06:00
Vladimir Sementsov-Ogievskiy
37e9403ea8 block/io: support int64_t bytes in bdrv_co_p{read,write}v_part()
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, prepare bdrv_co_preadv_part() and bdrv_co_pwritev_part() and their
remaining dependencies now.

bdrv_pad_request() is updated simultaneously, as pointer to bytes passed
to it both from bdrv_co_pwritev_part() and bdrv_co_preadv_part().

So, all callers of bdrv_pad_request() are updated to pass 64bit bytes.
bdrv_pad_request() is already good for 64bit requests, add
corresponding assertion.

Look at bdrv_co_preadv_part() and bdrv_co_pwritev_part().
Type is widening, so callers are safe. Let's look inside the functions.

In bdrv_co_preadv_part() and bdrv_aligned_pwritev() we only pass bytes
to other already int64_t interfaces (and some obviously safe
calculations), it's OK.

In bdrv_co_do_zero_pwritev() aligned_bytes may become large now, still
it's passed to bdrv_aligned_pwritev which supports int64_t bytes.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-15-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:17:11 -06:00
Vladimir Sementsov-Ogievskiy
8b0c5d7659 block/io: support int64_t bytes in bdrv_aligned_preadv()
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, prepare bdrv_aligned_preadv() now.

Make the bytes variable in bdrv_padding_rmw_read() int64_t, as it is
only used for pass-through to bdrv_aligned_preadv().

All bdrv_aligned_preadv() callers are safe as type is widening. Let's
look inside:

 - add a new-style assertion that request is good.
 - callees bdrv_is_allocated(), bdrv_co_do_copy_on_readv() supports
   int64_t bytes
 - conversion of bytes_remaining is OK, as we never have requests
   overflowing BDRV_MAX_LENGTH
 - looping through bytes_remaining is ok, num is updated to int64_t
   - for bdrv_driver_preadv we have same limit of max_transfer
   - qemu_iovec_memset is OK, as bytes+qiov_offset should not overflow
     qiov->size anyway (thanks to bdrv_check_qiov_request())

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-14-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: grammar tweak]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:17:11 -06:00
Vladimir Sementsov-Ogievskiy
9df5afbdd1 block/io: support int64_t bytes in bdrv_co_do_copy_on_readv()
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, prepare bdrv_co_do_copy_on_readv() now.

'bytes' type widening, so callers are safe. Look at the function
itself:

bytes, skip_bytes and progress become int64_t.

bdrv_round_to_clusters() is OK, cluster_bytes now may be large.
trace_bdrv_co_do_copy_on_readv() is OK

looping through cluster_bytes is still OK.

pnum is still capped to max_transfer, and to MAX_BOUNCE_BUFFER when we
are going to do COR operation. Therefor calculations in
qemu_iovec_from_buf() and bdrv_driver_preadv() should not change.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-13-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:17:11 -06:00
Vladimir Sementsov-Ogievskiy
fcfd9ade68 block/io: support int64_t bytes in bdrv_aligned_pwritev()
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, prepare bdrv_aligned_pwritev() now and convert the dependencies:
bdrv_co_write_req_prepare() and bdrv_co_write_req_finish() to signed
type bytes.

Conversion of bdrv_co_write_req_prepare() and
bdrv_co_write_req_finish() is definitely safe, as all requests in
block/io must not overflow BDRV_MAX_LENGTH. Still add assertions.

For bdrv_aligned_pwritev() 'bytes' type is widened, so callers are
safe. Let's check usage of the parameter inside the function.

Passing to bdrv_co_write_req_prepare() and bdrv_co_write_req_finish()
is OK.

Passing to qemu_iovec_* is OK after new assertion. All other callees
are already updated to int64_t.

Checking alignment is not changed, offset + bytes and qiov_offset +
bytes calculations are safe (thanks to new assertions).

max_transfer is kept to be int for now. It has a default of INT_MAX
here, and some drivers may rely on it. It's to be refactored later.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-12-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:16:03 -06:00
Vladimir Sementsov-Ogievskiy
5ae07b1410 block/io: support int64_t bytes in bdrv_co_do_pwrite_zeroes()
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, prepare bdrv_co_do_pwrite_zeroes() now.

Callers are safe, as converting int to int64_t is safe. Concentrate on
'bytes' usage in the function (thx to Eric Blake):

    compute 'int tail' via % 'int alignment' - safe
    fragmentation loop 'int num' - still fragments with a cap on
      max_transfer

    use of 'num' within the loop
    MIN(bytes, max_transfer) as well as %alignment - still works, so
         calculations in if (head) {} are safe
    clamp size by 'int max_write_zeroes' - safe
    drv->bdrv_co_pwrite_zeroes(int) - safe because of clamping
    clamp size by 'int max_transfer' - safe
    buf allocation is still clamped to max_transfer
    qemu_iovec_init_buf(size_t) - safe because of clamping
    bdrv_driver_pwritev(uint64_t) - safe

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-11-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:16:03 -06:00
Vladimir Sementsov-Ogievskiy
17abcbeee2 block/io: use int64_t bytes in driver wrappers
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

So, convert driver wrappers parameters which are already 64bit to
signed type.

Requests in block/io.c must never exceed BDRV_MAX_LENGTH (which is less
than INT64_MAX), which makes the conversion to signed 64bit type safe.

Add corresponding assertions.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-10-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:16:03 -06:00
Eric Blake
8024726459 block: use int64_t as bytes type in tracked requests
We are generally moving to int64_t for both offset and bytes parameters
on all io paths.

Main motivation is realization of 64-bit write_zeroes operation for
fast zeroing large disk chunks, up to the whole disk.

We chose signed type, to be consistent with off_t (which is signed) and
with possibility for signed return type (where negative value means
error).

All requests in block/io must not overflow BDRV_MAX_LENGTH, all
external users of BdrvTrackedRequest already have corresponding
assertions, so we are safe. Add some assertions still.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-9-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:14:15 -06:00
Vladimir Sementsov-Ogievskiy
63f4ad1186 block/io: improve bdrv_check_request: check qiov too
Operations with qiov add more restrictions on bytes, let's cover it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-8-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:14:00 -06:00
Vladimir Sementsov-Ogievskiy
98ca45494f block/io: bdrv_pad_request(): support qemu_iovec_init_extended failure
Make bdrv_pad_request() honest: return error if
qemu_iovec_init_extended() failed.

Update also bdrv_padding_destroy() to clean the structure for safety.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-6-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:14:00 -06:00
Vladimir Sementsov-Ogievskiy
f0deecff82 block/io: refactor bdrv_pad_request(): move bdrv_pad_request() up
Prepare for the following patch when bdrv_pad_request() will be able to
fail. Update the comments.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-5-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: grammar tweak]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:00:52 -06:00
Vladimir Sementsov-Ogievskiy
a56ed80c42 block: fix theoretical overflow in bdrv_init_padding()
Calculation of sum may theoretically overflow, so use 64bit type and
add some good assertions.

Use int64_t constantly.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-4-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: tweak assertion order]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:00:33 -06:00
Vladimir Sementsov-Ogievskiy
4c002cef0e util/iov: make qemu_iovec_init_extended() honest
Actually, we can't extend the io vector in all cases. Handle possible
MAX_IOV and size_t overflows.

For now add assertion to callers (actually they rely on success anyway)
and fix them in the following patch.

Add also some additional good assertions to qemu_iovec_init_slice()
while being here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-3-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:00:33 -06:00
Vladimir Sementsov-Ogievskiy
69b55e03f7 block: refactor bdrv_check_request: add errp
It's better to pass &error_abort than just assert that result is 0: on
crash, we'll immediately see the reason in the backtrace.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201211183934.169161-2-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: fix iotest 206 fallout]
Signed-off-by: Eric Blake <eblake@redhat.com>
2021-02-03 08:00:33 -06:00
Andrey Shinkevich
897dd0ec4f block: include supported_read_flags into BDS structure
Add the new member supported_read_flags to the BlockDriverState
structure. It will control the flags set for copy-on-read operations.
Make the block generic layer evaluate supported read flags before they
go to a block driver.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
 [vsementsov: use assert instead of abort]
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201216061703.70908-8-vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2021-01-26 14:36:37 +01:00
Vladimir Sementsov-Ogievskiy
d1a764d126 block: introduce BDRV_REQ_NO_WAIT flag
Add flag to make serialising request no wait: if there are conflicting
requests, just return error immediately. It's will be used in upcoming
preallocate filter.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201021145859.11201-7-vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
8ac5aab255 block: bdrv_mark_request_serialising: split non-waiting function
We'll need a separate function, which will only "mark" request
serialising with specified align but not wait for conflicting
requests. So, it will be like old bdrv_mark_request_serialising(),
before merging bdrv_wait_serialising_requests_locked() into it.

To reduce the possible mess, let's do the following:

Public function that does both marking and waiting will be called
bdrv_make_request_serialising, and private function which will only
"mark" will be called tracked_request_set_serialising().

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20201021145859.11201-6-vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
ec1c886831 block/io: bdrv_wait_serialising_requests_locked: drop extra bs arg
bs is linked in req, so no needs to pass it separately. Most of
tracked-requests API doesn't have bs argument. Actually, after this
patch only tracked_request_begin has it, but it's for purpose.

While being here, also add a comment about what "_locked" is.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201021145859.11201-5-vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
3183937ff9 block/io: split out bdrv_find_conflicting_request
To be reused in separate.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20201021145859.11201-4-vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00