block/reqlist: allow adding overlapping requests

Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already assert

block/reqlist: allow adding overlapping requests

Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already asserts the very same condition before calling
reqlist_init_req().

2. cbw_snapshot_read_lock()

There is no need to have read requests be non-overlapping in
copy-before-write when used for snapshot-access. In fact, there was no
protection against two callers of cbw_snapshot_read_lock() calling
reqlist_init_req() with overlapping ranges and this could lead to an
assertion failure [1].

In particular, with the reproducer script below [0], two
cbw_co_snapshot_block_status() callers could race, with the second
calling reqlist_init_req() before the first one finishes and removes
its conflicting request.

[0]:

> #!/bin/bash -e
> dd if=/dev/urandom of=/tmp/disk.raw bs=1M count=1024
> ./qemu-img create /tmp/fleecing.raw -f raw 1G
> (
> ./qemu-system-x86_64 --qmp stdio \
> --blockdev raw,node-name=node0,file.driver=file,file.filename=/tmp/disk.raw \
> --blockdev raw,node-name=node1,file.driver=file,file.filename=/tmp/fleecing.raw \
> <<EOF
> {"execute": "qmp_capabilities"}
> {"execute": "blockdev-add", "arguments": { "driver": "copy-before-write", "file": "node0", "target": "node1", "node-name": "node3" } }
> {"execute": "blockdev-add", "arguments": { "driver": "snapshot-access", "file": "node3", "node-name": "snap0" } }
> {"execute": "nbd-server-start", "arguments": {"addr": { "type": "unix", "data": { "path": "/tmp/nbd.socket" } } } }
> {"execute": "block-export-add", "arguments": {"id": "exp0", "node-name": "snap0", "type": "nbd", "name": "exp0"}}
> EOF
> ) &
> sleep 5
> while true; do
> ./qemu-nbd -d /dev/nbd0
> ./qemu-nbd -c /dev/nbd0 nbd:unix:/tmp/nbd.socket:exportname=exp0 -f raw -r
> nbdinfo --map 'nbd+unix:///exp0?socket=/tmp/nbd.socket'
> done

[1]:

> #5 0x000071e5f0088eb2 in __GI___assert_fail (...) at ./assert/assert.c:101
> #6 0x0000615285438017 in reqlist_init_req (...) at ../block/reqlist.c:23
> #7 0x00006152853e2d98 in cbw_snapshot_read_lock (...) at ../block/copy-before-write.c:237
> #8 0x00006152853e3068 in cbw_co_snapshot_block_status (...) at ../block/copy-before-write.c:304
> #9 0x00006152853f4d22 in bdrv_co_snapshot_block_status (...) at ../block/io.c:3726
> #10 0x000061528543a63e in snapshot_access_co_block_status (...) at ../block/snapshot-access.c:48
> #11 0x00006152853f1a0a in bdrv_co_do_block_status (...) at ../block/io.c:2474
> #12 0x00006152853f2016 in bdrv_co_common_block_status_above (...) at ../block/io.c:2652
> #13 0x00006152853f22cf in bdrv_co_block_status_above (...) at ../block/io.c:2732
> #14 0x00006152853d9a86 in blk_co_block_status_above (...) at ../block/block-backend.c:1473
> #15 0x000061528538da6c in blockstatus_to_extents (...) at ../nbd/server.c:2374
> #16 0x000061528538deb1 in nbd_co_send_block_status (...) at ../nbd/server.c:2481
> #17 0x000061528538f424 in nbd_handle_request (...) at ../nbd/server.c:2978
> #18 0x000061528538f906 in nbd_trip (...) at ../nbd/server.c:3121
> #19 0x00006152855a7caf in coroutine_trampoline (...) at ../util/coroutine-ucontext.c:175

Cc: qemu-stable@nongnu.org
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240712140716.517911-1-f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
(cherry picked from commit 6475155d519209c80fdda53e05130365aa769838)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

show more ...

Merge tag 'pull-block-jobs-2024-09-30' of https://gitlab.com/vsementsov/qemu into staging

Block-jobs: improve backup fleecing

# -----BEGIN PGP SIGNATURE-----
#
# iQIzBAABCgAdFiEEi5wmzbL9FHyIDoahVh8

Merge tag 'pull-block-jobs-2024-09-30' of https://gitlab.com/vsementsov/qemu into staging

Block-jobs: improve backup fleecing

# -----BEGIN PGP SIGNATURE-----
#
# iQIzBAABCgAdFiEEi5wmzbL9FHyIDoahVh8kwfGfefsFAmb6WsYACgkQVh8kwfGf
# eftECRAAgRFGeVSE8+fgibsHH4TixG41Rg/4gi09KZuhNHCDQXiVWlpNf4isnjcg
# K3PAZh5XSr+ClYFzbwqrjnbjGOZDJRpfb5KAnWK2GhhbBrwFBAussJ/njOg3IB3V
# 1Qtm5cc6aKrFW4dybqWW96gZZkIxFuSOW0jAjuVh4r0ZfK03Xytm5WITYg7CLnnQ
# WqnseoQuj9HvT3F2A3HnRk4tIlgEb2eWppDhX8DiW/IO4C1ScfYpyP2cvUROCCGF
# GIJKv7/GRYosSUx4nsCCx1y7ISX0A5m1sCBlWbnQmYLIaJ/JpUYA2Tqxyfy3LTRE
# IJK/NcWcR9fCy2W1hNQJaKfIKoA7EdfqSvCFQmBHrEmtRYslejNRB3PjIUzth7Oh
# knfHxKSiXyGBdikaE5a//MUBK74pc9eC9zuIvIzxdLYxBTTGKZlTuhxG28QBoLO3
# /IcPd22loEZwh6PRgcFw7olsHo9lhfbiRua8dKwj384yJKFGU4s4QghSqRLxBHjP
# xnqQrU8uE3UOIVMY9ahsMxwUzzYGbwi0vQw98qLm26vcQBZRD1C9L97M9yCCrhQ4
# jfWyMsqdODA6V3IRpIV+JBL5KvRkC1fuoAw6Oh5R2r3K/WpX74gthATna9+/wGno
# 0wPiaEvBox8y6zLKAZe4MEA6phX0tb5In6OQB2JlILHa7gds4x4=
# =LqMR
# -----END PGP SIGNATURE-----
# gpg: Signature made Mon 30 Sep 2024 09:01:10 BST
# gpg: using RSA key 8B9C26CDB2FD147C880E86A1561F24C1F19F79FB
# gpg: Good signature from "Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>" [unknown]
# gpg: aka "Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 8B9C 26CD B2FD 147C 880E 86A1 561F 24C1 F19F 79FB

* tag 'pull-block-jobs-2024-09-30' of https://gitlab.com/vsementsov/qemu:
util/co-shared-resource: Remove unused co_try_get_from_shres
block: Remove unused aio_task_pool_empty
block/reqlist: allow adding overlapping requests
backup: add minimum cluster size to performance options
copy-before-write: allow specifying minimum cluster size

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

block/reqlist: allow adding overlapping requests

Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already assert

block/reqlist: allow adding overlapping requests

Allow overlapping request by removing the assert that made it
impossible. There are only two callers:

1. block_copy_task_create()

It already asserts the very same condition before calling
reqlist_init_req().

2. cbw_snapshot_read_lock()

There is no need to have read requests be non-overlapping in
copy-before-write when used for snapshot-access. In fact, there was no
protection against two callers of cbw_snapshot_read_lock() calling
reqlist_init_req() with overlapping ranges and this could lead to an
assertion failure [1].

In particular, with the reproducer script below [0], two
cbw_co_snapshot_block_status() callers could race, with the second
calling reqlist_init_req() before the first one finishes and removes
its conflicting request.

[0]:

> #!/bin/bash -e
> dd if=/dev/urandom of=/tmp/disk.raw bs=1M count=1024
> ./qemu-img create /tmp/fleecing.raw -f raw 1G
> (
> ./qemu-system-x86_64 --qmp stdio \
> --blockdev raw,node-name=node0,file.driver=file,file.filename=/tmp/disk.raw \
> --blockdev raw,node-name=node1,file.driver=file,file.filename=/tmp/fleecing.raw \
> <<EOF
> {"execute": "qmp_capabilities"}
> {"execute": "blockdev-add", "arguments": { "driver": "copy-before-write", "file": "node0", "target": "node1", "node-name": "node3" } }
> {"execute": "blockdev-add", "arguments": { "driver": "snapshot-access", "file": "node3", "node-name": "snap0" } }
> {"execute": "nbd-server-start", "arguments": {"addr": { "type": "unix", "data": { "path": "/tmp/nbd.socket" } } } }
> {"execute": "block-export-add", "arguments": {"id": "exp0", "node-name": "snap0", "type": "nbd", "name": "exp0"}}
> EOF
> ) &
> sleep 5
> while true; do
> ./qemu-nbd -d /dev/nbd0
> ./qemu-nbd -c /dev/nbd0 nbd:unix:/tmp/nbd.socket:exportname=exp0 -f raw -r
> nbdinfo --map 'nbd+unix:///exp0?socket=/tmp/nbd.socket'
> done

[1]:

> #5 0x000071e5f0088eb2 in __GI___assert_fail (...) at ./assert/assert.c:101
> #6 0x0000615285438017 in reqlist_init_req (...) at ../block/reqlist.c:23
> #7 0x00006152853e2d98 in cbw_snapshot_read_lock (...) at ../block/copy-before-write.c:237
> #8 0x00006152853e3068 in cbw_co_snapshot_block_status (...) at ../block/copy-before-write.c:304
> #9 0x00006152853f4d22 in bdrv_co_snapshot_block_status (...) at ../block/io.c:3726
> #10 0x000061528543a63e in snapshot_access_co_block_status (...) at ../block/snapshot-access.c:48
> #11 0x00006152853f1a0a in bdrv_co_do_block_status (...) at ../block/io.c:2474
> #12 0x00006152853f2016 in bdrv_co_common_block_status_above (...) at ../block/io.c:2652
> #13 0x00006152853f22cf in bdrv_co_block_status_above (...) at ../block/io.c:2732
> #14 0x00006152853d9a86 in blk_co_block_status_above (...) at ../block/block-backend.c:1473
> #15 0x000061528538da6c in blockstatus_to_extents (...) at ../nbd/server.c:2374
> #16 0x000061528538deb1 in nbd_co_send_block_status (...) at ../nbd/server.c:2481
> #17 0x000061528538f424 in nbd_handle_request (...) at ../nbd/server.c:2978
> #18 0x000061528538f906 in nbd_trip (...) at ../nbd/server.c:3121
> #19 0x00006152855a7caf in coroutine_trampoline (...) at ../util/coroutine-ucontext.c:175

Cc: qemu-stable@nongnu.org
Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240712140716.517911-1-f.ebner@proxmox.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>

show more ...

Merge remote-tracking branch 'remotes/hreitz-gitlab/tags/pull-block-2022-03-07' into staging

Block patches for 7.0-rc0:
- New fleecing backup scheme
- iotest fixes
- Fixes for the curl block driver

Merge remote-tracking branch 'remotes/hreitz-gitlab/tags/pull-block-2022-03-07' into staging

Block patches for 7.0-rc0:
- New fleecing backup scheme
- iotest fixes
- Fixes for the curl block driver
- Fix for the preallocate block driver
- IDE fix for zero-length TRIM requests

# gpg: Signature made Mon 07 Mar 2022 10:33:31 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

* remotes/hreitz-gitlab/tags/pull-block-2022-03-07: (23 commits)
iotests/image-fleecing: test push backup with fleecing
iotests/image-fleecing: add test case with bitmap
iotests.py: add qemu_io_pipe_and_status()
iotests/image-fleecing: add test-case for fleecing format node
block: copy-before-write: realize snapshot-access API
block: introduce snapshot-access block driver
block/io: introduce block driver snapshot-access API
block/reqlist: add reqlist_wait_all()
block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()
block/reqlist: reqlist_find_conflict(): use ranges_overlap()
block: intoduce reqlist
block/block-copy: add block_copy_reset()
block/copy-before-write: add bitmap open parameter
block/block-copy: block_copy_state_new(): add bitmap parameter
block/dirty-bitmap: bdrv_merge_dirty_bitmap(): add return value
block/block-copy: move copy_bitmap initialization to block_copy_state_new()
iotests: Write test output to TEST_DIR
tests/qemu-iotests/testrunner: Quote "case not run" lines in TAP mode
tests/qemu-iotests/040: Skip TestCommitWithFilters without 'throttle'
block: fix preallocate filter: don't do unaligned preallocate requests
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

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>
Re

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>

show more ...

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@r

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>

show more ...

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: V

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>

show more ...