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2020-08-21meson: convert blockMarc-André Lureau
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21trace: switch position of headers to what Meson requiresPaolo Bonzini
Meson doesn't enjoy the same flexibility we have with Make in choosing the include path. In particular the tracing headers are using $(build_root)/$(<D). In order to keep the include directives unchanged, the simplest solution is to generate headers with patterns like "trace/trace-audio.h" and place forwarding headers in the source tree such that for example "audio/trace.h" includes "trace/trace-audio.h". This patch is too ugly to be applied to the Makefiles now. It's only a way to separate the changes to the tracing header files from the Meson rewrite of the tracing logic. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-10block/block-copy: always align copied region to cluster sizeStefan Reiter
Since commit 42ac214406e0 (block/block-copy: refactor task creation) block_copy_task_create calculates the area to be copied via bdrv_dirty_bitmap_next_dirty_area, but that can return an unaligned byte count if the image's last cluster end is not aligned to the bitmap's granularity. Always ALIGN_UP the resulting bytes value to satisfy block_copy_do_copy, which requires the 'bytes' parameter to be aligned to cluster size. Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Stefan Reiter <s.reiter@proxmox.com> Message-Id: <20200810095523.15071-1-s.reiter@proxmox.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-08-05qcow2-cluster: Fix integer left shift error in qcow2_alloc_cluster_link_l2()Tuguoyi
When calculating the offset, the result of left shift operation will be promoted to type int64 automatically because the left operand of + operator is uint64_t. but the result after integer promotion may be produce an error value for us and trigger the following asserting error. For example, consider i=0x2000, cluster_bits=18, the result of left shift operation will be 0x80000000. Cause argument i is of signed integer type, the result is automatically promoted to 0xffffffff80000000 which is not we expected The way to trigger the assertion error: qemu-img create -f qcow2 -o preallocation=full,cluster_size=256k tmpdisk 10G This patch fix it by casting @i to uint64_t before doing left shift operation Signed-off-by: Guoyi Tu <tu.guoyi@h3c.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 81ba90fe0c014f269621c283269b42ad@h3c.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-08-03qcow2: Release read-only bitmaps when inactivatedMax Reitz
During migration, we release all bitmaps after storing them on disk, as long as they are (1) stored on disk, (2) not read-only, and (3) consistent. (2) seems arbitrary, though. The reason we do not release them is because we do not write them, as there is no need to; and then we just forget about all bitmaps that we have not written to the file. However, read-only persistent bitmaps are still in the file and in sync with their in-memory representation, so we may as well release them just like any R/W bitmap that we have updated. It leads to actual problems, too: After migration, letting the source continue may result in an error if there were any bitmaps on read-only nodes (such as backing images), because those have not been released by bdrv_inactive_all(), but bdrv_invalidate_cache_all() attempts to reload them (which fails, because they are still present in memory). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200730120234.49288-2-mreitz@redhat.com> Tested-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28Merge remote-tracking branch 'remotes/ericb/tags/pull-nbd-2020-07-28' into ↵Peter Maydell
staging nbd patches for 2020-07-28 - fix NBD handling of trim/zero requests larger than 2G - allow no-op resizes on NBD (in turn fixing qemu-img convert -c into NBD) - several deadlock fixes when using NBD reconnect # gpg: Signature made Tue 28 Jul 2020 15:59:42 BST # 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-2020-07-28: block/nbd: nbd_co_reconnect_loop(): don't sleep if drained block/nbd: on shutdown terminate connection attempt block/nbd: allow drain during reconnect attempt block/nbd: split nbd_establish_connection out of nbd_client_connect iotests: Test convert to qcow2 compressed to NBD iotests: Add more qemu_img helpers iotests: Make qemu_nbd_popen() a contextmanager block: nbd: Fix convert qcow2 compressed to nbd nbd: Fix large trim/zero requests Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-28Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2020-07-28' ↵Peter Maydell
into staging Block patches for 5.1.0: - Fix block I/O for split transfers - Fix iotest 197 for non-qcow2 formats # gpg: Signature made Tue 28 Jul 2020 14:45:28 BST # gpg: using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40 # gpg: issuer "mreitz@redhat.com" # gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full] # Primary key fingerprint: 91BE B60A 30DB 3E88 57D1 1829 F407 DB00 61D5 CF40 * remotes/maxreitz/tags/pull-block-2020-07-28: iotests/197: Fix for non-qcow2 formats iotests/028: Add test for cross-base-EOF reads block: Fix bdrv_aligned_p*v() for qiov_offset != 0 Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-28block/nbd: nbd_co_reconnect_loop(): don't sleep if drainedVladimir Sementsov-Ogievskiy
We try to go to wakeable sleep, so that, if drain begins it will break the sleep. But what if nbd_client_co_drain_begin() already called and s->drained is already true? We'll go to sleep, and drain will have to wait for the whole timeout. Let's improve it. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200727184751.15704-5-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28block/nbd: on shutdown terminate connection attemptVladimir Sementsov-Ogievskiy
On shutdown nbd driver may be in a connecting state. We should shutdown it as well, otherwise we may hang in nbd_teardown_connection, waiting for conneciton_co to finish in BDRV_POLL_WHILE(bs, s->connection_co) loop if remote server is down. How to reproduce the dead lock: 1. Create nbd-fault-injector.conf with the following contents: [inject-error "mega1"] event=data io=readwrite when=before 2. In one terminal run nbd-fault-injector in a loop, like this: n=1; while true; do echo $n; ((n++)); ./nbd-fault-injector.py 127.0.0.1:10000 nbd-fault-injector.conf; done 3. In another terminal run qemu-io in a loop, like this: n=1; while true; do echo $n; ((n++)); ./qemu-io -c 'read 0 512' nbd://127.0.0.1:10000; done After some time, qemu-io will hang. Note, that this hang may be triggered by another bug, so the whole case is fixed only together with commit "block/nbd: allow drain during reconnect attempt". Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200727184751.15704-4-vsementsov@virtuozzo.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28block/nbd: allow drain during reconnect attemptVladimir Sementsov-Ogievskiy
It should be safe to reenter qio_channel_yield() on io/channel read/write path, so it's safe to reduce in_flight and allow attaching new aio context. And no problem to allow drain itself: connection attempt is not a guest request. Moreover, if remote server is down, we can hang in negotiation, blocking drain section and provoking a dead lock. How to reproduce the dead lock: 1. Create nbd-fault-injector.conf with the following contents: [inject-error "mega1"] event=data io=readwrite when=before 2. In one terminal run nbd-fault-injector in a loop, like this: n=1; while true; do echo $n; ((n++)); ./nbd-fault-injector.py 127.0.0.1:10000 nbd-fault-injector.conf; done 3. In another terminal run qemu-io in a loop, like this: n=1; while true; do echo $n; ((n++)); ./qemu-io -c 'read 0 512' nbd://127.0.0.1:10000; done After some time, qemu-io will hang trying to drain, for example, like this: #3 aio_poll (ctx=0x55f006bdd890, blocking=true) at util/aio-posix.c:600 #4 bdrv_do_drained_begin (bs=0x55f006bea710, recursive=false, parent=0x0, ignore_bds_parents=false, poll=true) at block/io.c:427 #5 bdrv_drained_begin (bs=0x55f006bea710) at block/io.c:433 #6 blk_drain (blk=0x55f006befc80) at block/block-backend.c:1710 #7 blk_unref (blk=0x55f006befc80) at block/block-backend.c:498 #8 bdrv_open_inherit (filename=0x7fffba1563bc "nbd+tcp://127.0.0.1:10000", reference=0x0, options=0x55f006be86d0, flags=24578, parent=0x0, child_class=0x0, child_role=0, errp=0x7fffba154620) at block.c:3491 #9 bdrv_open (filename=0x7fffba1563bc "nbd+tcp://127.0.0.1:10000", reference=0x0, options=0x0, flags=16386, errp=0x7fffba154620) at block.c:3513 #10 blk_new_open (filename=0x7fffba1563bc "nbd+tcp://127.0.0.1:10000", reference=0x0, options=0x0, flags=16386, errp=0x7fffba154620) at block/block-backend.c:421 And connection_co stack like this: #0 qemu_coroutine_switch (from_=0x55f006bf2650, to_=0x7fe96e07d918, action=COROUTINE_YIELD) at util/coroutine-ucontext.c:302 #1 qemu_coroutine_yield () at util/qemu-coroutine.c:193 #2 qio_channel_yield (ioc=0x55f006bb3c20, condition=G_IO_IN) at io/channel.c:472 #3 qio_channel_readv_all_eof (ioc=0x55f006bb3c20, iov=0x7fe96d729bf0, niov=1, errp=0x7fe96d729eb0) at io/channel.c:110 #4 qio_channel_readv_all (ioc=0x55f006bb3c20, iov=0x7fe96d729bf0, niov=1, errp=0x7fe96d729eb0) at io/channel.c:143 #5 qio_channel_read_all (ioc=0x55f006bb3c20, buf=0x7fe96d729d28 "\300.\366\004\360U", buflen=8, errp=0x7fe96d729eb0) at io/channel.c:247 #6 nbd_read (ioc=0x55f006bb3c20, buffer=0x7fe96d729d28, size=8, desc=0x55f004f69644 "initial magic", errp=0x7fe96d729eb0) at /work/src/qemu/master/include/block/nbd.h:365 #7 nbd_read64 (ioc=0x55f006bb3c20, val=0x7fe96d729d28, desc=0x55f004f69644 "initial magic", errp=0x7fe96d729eb0) at /work/src/qemu/master/include/block/nbd.h:391 #8 nbd_start_negotiate (aio_context=0x55f006bdd890, ioc=0x55f006bb3c20, tlscreds=0x0, hostname=0x0, outioc=0x55f006bf19f8, structured_reply=true, zeroes=0x7fe96d729dca, errp=0x7fe96d729eb0) at nbd/client.c:904 #9 nbd_receive_negotiate (aio_context=0x55f006bdd890, ioc=0x55f006bb3c20, tlscreds=0x0, hostname=0x0, outioc=0x55f006bf19f8, info=0x55f006bf1a00, errp=0x7fe96d729eb0) at nbd/client.c:1032 #10 nbd_client_connect (bs=0x55f006bea710, errp=0x7fe96d729eb0) at block/nbd.c:1460 #11 nbd_reconnect_attempt (s=0x55f006bf19f0) at block/nbd.c:287 #12 nbd_co_reconnect_loop (s=0x55f006bf19f0) at block/nbd.c:309 #13 nbd_connection_entry (opaque=0x55f006bf19f0) at block/nbd.c:360 #14 coroutine_trampoline (i0=113190480, i1=22000) at util/coroutine-ucontext.c:173 Note, that the hang may be triggered by another bug, so the whole case is fixed only together with commit "block/nbd: on shutdown terminate connection attempt". Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200727184751.15704-3-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28block/nbd: split nbd_establish_connection out of nbd_client_connectVladimir Sementsov-Ogievskiy
We are going to implement non-blocking version of nbd_establish_connection, which for a while will be used only for nbd_reconnect_attempt, not for nbd_open, so we need to call it separately. Refactor nbd_reconnect_attempt in a way which makes next commit simpler. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200727184751.15704-2-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28block: nbd: Fix convert qcow2 compressed to nbdNir Soffer
When converting to qcow2 compressed format, the last step is a special zero length compressed write, ending in a call to bdrv_co_truncate(). This call always fails for the nbd driver since it does not implement bdrv_co_truncate(). For block devices, which have the same limits, the call succeeds since the file driver implements bdrv_co_truncate(). If the caller asked to truncate to the same or smaller size with exact=false, the truncate succeeds. Implement the same logic for nbd. Example failing without this change: In one shell start qemu-nbd: $ truncate -s 1g test.tar $ qemu-nbd --socket=/tmp/nbd.sock --persistent --format=raw --offset 1536 test.tar In another shell convert an image to qcow2 compressed via NBD: $ echo "disk data" > disk.raw $ truncate -s 1g disk.raw $ qemu-img convert -f raw -O qcow2 -c disk1.raw nbd+unix:///?socket=/tmp/nbd.sock; echo $? 1 qemu-img failed, but the conversion was successful: $ qemu-img info nbd+unix:///?socket=/tmp/nbd.sock image: nbd+unix://?socket=/tmp/nbd.sock file format: qcow2 virtual size: 1 GiB (1073741824 bytes) ... $ qemu-img check nbd+unix:///?socket=/tmp/nbd.sock No errors were found on the image. 1/16384 = 0.01% allocated, 100.00% fragmented, 100.00% compressed clusters Image end offset: 393216 $ qemu-img compare disk.raw nbd+unix:///?socket=/tmp/nbd.sock Images are identical. Fixes: https://bugzilla.redhat.com/1860627 Signed-off-by: Nir Soffer <nsoffer@redhat.com> Message-Id: <20200727215846.395443-2-nsoffer@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> [eblake: typo fixes] Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-28Merge remote-tracking branch 'remotes/ericb/tags/pull-bitmaps-2020-07-27' ↵Peter Maydell
into staging bitmaps patches for 2020-07-27 - Improve handling of various post-copy bitmap migration scenarios. A lost bitmap should merely mean that the next backup must be full rather than incremental, rather than abruptly breaking the entire guest migration. - Associated iotest improvements # gpg: Signature made Mon 27 Jul 2020 21:46:17 BST # 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-bitmaps-2020-07-27: (24 commits) migration: Fix typos in bitmap migration comments iotests: Adjust which migration tests are quick qemu-iotests/199: add source-killed case to bitmaps postcopy qemu-iotests/199: add early shutdown case to bitmaps postcopy qemu-iotests/199: check persistent bitmaps qemu-iotests/199: prepare for new test-cases addition migration/savevm: don't worry if bitmap migration postcopy failed migration/block-dirty-bitmap: cancel migration on shutdown migration/block-dirty-bitmap: relax error handling in incoming part migration/block-dirty-bitmap: keep bitmap state for all bitmaps migration/block-dirty-bitmap: simplify dirty_bitmap_load_complete migration/block-dirty-bitmap: rename finish_lock to just lock migration/block-dirty-bitmap: refactor state global variables migration/block-dirty-bitmap: move mutex init to dirty_bitmap_mig_init migration/block-dirty-bitmap: rename dirty_bitmap_mig_cleanup migration/block-dirty-bitmap: rename state structure types migration/block-dirty-bitmap: fix dirty_bitmap_mig_before_vm_start qemu-iotests/199: increase postcopy period qemu-iotests/199: change discard patterns qemu-iotests/199: improve performance: set bitmap by discard ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-28block: Fix bdrv_aligned_p*v() for qiov_offset != 0Max Reitz
Since these functions take a @qiov_offset, they must always take it into account when working with @qiov. There are a couple of places where they do not, but they should. Fixes: 65cd4424b9df03bb5195351c33e04cbbecc0705c ("block/io: bdrv_aligned_preadv: use and support qiov_offset") Fixes: 28c4da28695bdbe04b336b2c9c463876cc3aaa6d ("block/io: bdrv_aligned_pwritev: use and support qiov_offset") Reported-by: Claudio Fontana <cfontana@suse.de> Reported-by: Bruce Rogers <brogers@suse.com> Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200728120806.265916-2-mreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Tested-by: Claudio Fontana <cfontana@suse.de> Tested-by: Bruce Rogers <brogers@suse.com>
2020-07-27qcow2: Fix capitalization of header extension constant.Andrey Shinkevich
Make the capitalization of the hexadecimal numbers consistent for the QCOW2 header extension constants in docs/interop/qcow2.txt. Suggested-by: Eric Blake <eblake@redhat.com> Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <1594973699-781898-2-git-send-email-andrey.shinkevich@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com>
2020-07-27block/amend: Check whether the node existsMax Reitz
We should check whether the user-specified node-name actually refers to a node. The simplest way to do that is to use bdrv_lookup_bs() instead of bdrv_find_node() (the former wraps the latter, and produces an error message if necessary). Reported-by: Coverity (CID 1430268) Fixes: ced914d0ab9fb2c900f873f6349a0b8eecd1fdbe Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200710095037.10885-1-mreitz@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
2020-07-21Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell
Block layer patches: - file-posix: Handle `EINVAL` fallocate return value - qemu-img convert -n: Keep qcow2 v2 target sparse # gpg: Signature made Tue 21 Jul 2020 16:45:28 BST # gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6 # gpg: issuer "kwolf@redhat.com" # gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full] # Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6 * remotes/kevin/tags/for-upstream: iotests: Test sparseness for qemu-img convert -n qcow2: Implement v2 zero writes with discard if possible file-posix: Handle `EINVAL` fallocate return value Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-21Merge remote-tracking branch 'remotes/armbru/tags/pull-qom-2020-07-21' into ↵Peter Maydell
staging QOM patches for 2020-07-21 # gpg: Signature made Tue 21 Jul 2020 16:40:27 BST # gpg: using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653 # gpg: issuer "armbru@redhat.com" # gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full] # gpg: aka "Markus Armbruster <armbru@pond.sub.org>" [full] # Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653 * remotes/armbru/tags/pull-qom-2020-07-21: qom: Make info qom-tree sort children more efficiently qom: Document object_get_canonical_path() returns malloced string qom: Change object_get_canonical_path_component() not to malloc Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-21qcow2: Implement v2 zero writes with discard if possibleKevin Wolf
qcow2 version 2 images don't support the zero flag for clusters, so for write_zeroes requests, we return -ENOTSUP and get explicit zero buffer writes. If the image doesn't have a backing file, we can do better: Just discard the respective clusters. This is relevant for 'qemu-img convert -O qcow2 -n', where qemu-img has to assume that the existing target image may contain any data, so it has to write zeroes. Without this patch, this results in a fully allocated target image, even if the source image was empty. Reported-by: Nir Soffer <nsoffer@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200721135520.72355-2-kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-21file-posix: Handle `EINVAL` fallocate return valueAntoine Damhet
The `detect-zeroes=unmap` option may issue unaligned `FALLOC_FL_PUNCH_HOLE` requests, raw block devices can (and will) return `EINVAL`, qemu should then write the zeroes to the blockdev instead of issuing an `IO_ERROR`. The problem can be reprodced like this: $ qemu-io -c 'write -P 0 42 1234' --image-opts driver=host_device,filename=/dev/loop0,detect-zeroes=unmap write failed: Invalid argument Signed-off-by: Antoine Damhet <antoine.damhet@blade-group.com> Message-Id: <20200717135603.51180-1-antoine.damhet@blade-group.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-21qom: Change object_get_canonical_path_component() not to mallocMarkus Armbruster
object_get_canonical_path_component() returns a malloced copy of a property name on success, null on failure. 19 of its 25 callers immediately free the returned copy. Change object_get_canonical_path_component() to return the property name directly. Since modifying the name would be wrong, adjust the return type to const char *. Drop the free from the 19 callers become simpler, add the g_strdup() to the other six. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200714160202.3121879-4-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Li Qiang <liq3ea@gmail.com>
2020-07-21block: fix bdrv_aio_cancel() for ENOMEDIUM requestsStefan Hajnoczi
bdrv_aio_cancel() calls aio_poll() on the AioContext for the given I/O request until it has completed. ENOMEDIUM requests are special because there is no BlockDriverState when the drive has no medium! Define a .get_aio_context() function for BlkAioEmAIOCB requests so that bdrv_aio_cancel() can find the AioContext where the completion BH is pending. Without this function bdrv_aio_cancel() aborts on ENOMEDIUM requests! libFuzzer triggered the following assertion: cat << EOF | qemu-system-i386 -M pc-q35-5.0 \ -nographic -monitor none -serial none \ -qtest stdio -trace ide\* outl 0xcf8 0x8000fa24 outl 0xcfc 0xe106c000 outl 0xcf8 0x8000fa04 outw 0xcfc 0x7 outl 0xcf8 0x8000fb20 write 0x0 0x3 0x2780e7 write 0xe106c22c 0xd 0x1130c218021130c218021130c2 write 0xe106c218 0x15 0x110010110010110010110010110010110010110010 EOF ide_exec_cmd IDE exec cmd: bus 0x56170a77a2b8; state 0x56170a77a340; cmd 0xe7 ide_reset IDEstate 0x56170a77a340 Aborted (core dumped) (gdb) bt #1 0x00007ffff4f93895 in abort () at /lib64/libc.so.6 #2 0x0000555555dc6c00 in bdrv_aio_cancel (acb=0x555556765550) at block/io.c:2745 #3 0x0000555555dac202 in blk_aio_cancel (acb=0x555556765550) at block/block-backend.c:1546 #4 0x0000555555b1bd74 in ide_reset (s=0x555557213340) at hw/ide/core.c:1318 #5 0x0000555555b1e3a1 in ide_bus_reset (bus=0x5555572132b8) at hw/ide/core.c:2422 #6 0x0000555555b2aa27 in ahci_reset_port (s=0x55555720eb50, port=2) at hw/ide/ahci.c:650 #7 0x0000555555b29fd7 in ahci_port_write (s=0x55555720eb50, port=2, offset=44, val=16) at hw/ide/ahci.c:360 #8 0x0000555555b2a564 in ahci_mem_write (opaque=0x55555720eb50, addr=556, val=16, size=1) at hw/ide/ahci.c:513 #9 0x000055555598415b in memory_region_write_accessor (mr=0x55555720eb80, addr=556, value=0x7fffffffb838, size=1, shift=0, mask=255, attrs=...) at softmmu/memory.c:483 Looking at bdrv_aio_cancel: 2728 /* async I/Os */ 2729 2730 void bdrv_aio_cancel(BlockAIOCB *acb) 2731 { 2732 qemu_aio_ref(acb); 2733 bdrv_aio_cancel_async(acb); 2734 while (acb->refcnt > 1) { 2735 if (acb->aiocb_info->get_aio_context) { 2736 aio_poll(acb->aiocb_info->get_aio_context(acb), true); 2737 } else if (acb->bs) { 2738 /* qemu_aio_ref and qemu_aio_unref are not thread-safe, so 2739 * assert that we're not using an I/O thread. Thread-safe 2740 * code should use bdrv_aio_cancel_async exclusively. 2741 */ 2742 assert(bdrv_get_aio_context(acb->bs) == qemu_get_aio_context()); 2743 aio_poll(bdrv_get_aio_context(acb->bs), true); 2744 } else { 2745 abort(); <=============== 2746 } 2747 } 2748 qemu_aio_unref(acb); 2749 } Fixes: 02c50efe08736116048d5fc355043080f4d5859c ("block: Add bdrv_aio_cancel_async") Reported-by: Alexander Bulekov <alxndr@bu.edu> Buglink: https://bugs.launchpad.net/qemu/+bug/1878255 Originally-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20200720100141.129739-1-stefanha@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-07-21block/crypto: disallow write sharing by defaultMaxim Levitsky
My commit 'block/crypto: implement the encryption key management' accidently allowed raw luks images to be shared between different qemu processes without share-rw=on explicit override. Fix that. Fixes: bbfdae91fb ("block/crypto: implement the encryption key management") Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1857490 Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200719122059.59843-2-mlevitsk@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-07-17file-posix: Fix leaked fd in raw_open_common() error pathKevin Wolf
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200717105426.51134-4-kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-17file-posix: Fix check_hdev_writable() with auto-read-onlyKevin Wolf
For Linux block devices, being able to open the device read-write doesn't necessarily mean that the device is actually writable (one example is a read-only LV, as you get with lvchange -pr <device>). We have check_hdev_writable() to check this condition and fail opening the image read-write if it's not actually writable. However, this check doesn't take auto-read-only into account, but results in a hard failure instead of downgrading to read-only where possible. Fix this and do the writable check not based on BDRV_O_RDWR, but only when this actually results in opening the file read-write. A second check is inserted in raw_reconfigure_getfd() to have the same check when dynamic auto-read-only upgrades an image file from read-only to read-write. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200717105426.51134-3-kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-17file-posix: Move check_hdev_writable() upKevin Wolf
We'll need to call it in raw_open_common(), so move the function to avoid a forward declaration. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200717105426.51134-2-kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-17file-posix: Allow byte-aligned O_DIRECT with NFSKevin Wolf
Since commit a6b257a08e3 ('file-posix: Handle undetectable alignment'), we assume that if we open a file with O_DIRECT and alignment probing returns 1, we just couldn't find out the real alignment requirement because some filesystems make the requirement only for allocated blocks. In this case, a safe default of 4k is used. This is too strict for NFS, which does actually allow byte-aligned requests even with O_DIRECT. Because we can't distinguish both cases with generic code, let's just look at the file system magic and disable s->needs_alignment for NFS. This way, O_DIRECT can still be used on NFS for images that are not aligned to 4k. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200716142601.111237-3-kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-17Remove VXHS block deviceMarc-André Lureau
The vxhs code doesn't compile since v2.12.0. There's no point in fixing and then adding CI for a config that our users have demonstrated that they do not use; better to just remove it. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200711065926.2204721-1-marcandre.lureau@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell
Block layer patches: - file-posix: Mitigate file fragmentation with extent size hints - Tighten qemu-img rules on missing backing format - qemu-img map: Don't limit block status request size - Fix crash with virtio-scsi and iothreads # gpg: Signature made Tue 14 Jul 2020 14:24:19 BST # gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6 # gpg: issuer "kwolf@redhat.com" # gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full] # Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6 * remotes/kevin/tags/for-upstream: block: Avoid stale pointer dereference in blk_get_aio_context() qemu-img: Deprecate use of -b without -F block: Add support to warn on backing file change without format iotests: Specify explicit backing format where sensible qcow2: Deprecate use of qemu-img amend to change backing file block: Error if backing file fails during creation without -u qcow: Tolerate backing_fmt= vmdk: Add trivial backing_fmt support sheepdog: Add trivial backing_fmt support block: Finish deprecation of 'qemu-img convert -n -o' qemu-img: Flush stdout before before potential stderr messages file-posix: Mitigate file fragmentation with extent size hints iotests/059: Filter out disk size with more standard filter qemu-img map: Don't limit block status request size iotests: Simplify _filter_img_create() a bit Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-07-14block: Avoid stale pointer dereference in blk_get_aio_context()Greg Kurz
It is possible for blk_remove_bs() to race with blk_drain_all(), causing the latter to dereference a stale blk->root pointer: blk_remove_bs(blk) bdrv_root_unref_child(blk->root) child_bs = blk->root->bs bdrv_detach_child(blk->root) ... g_free(blk->root) <============== blk->root becomes stale bdrv_unref(child_bs) <============ yield at some point A blk_drain_all() can be triggered by some guest action in the meantime, eg. on POWER, SLOF might disable bus mastering on a virtio-scsi-pci device: virtio_write_config() virtio_pci_stop_ioeventfd() virtio_bus_stop_ioeventfd() virtio_scsi_dataplane_stop() blk_drain_all() blk_get_aio_context() bs = blk->root ? blk->root->bs : NULL ^^^^^^^^^ stale Then, depending on one's luck, QEMU either crashes with SEGV or hits the assertion in blk_get_aio_context(). blk->root is set by blk_insert_bs() which calls bdrv_root_attach_child() first. The blk_remove_bs() function should rollback the changes made by blk_insert_bs() in the opposite order (or it should be documented somewhere why this isn't the case). Clear blk->root before calling bdrv_root_unref_child() in blk_remove_bs(). Signed-off-by: Greg Kurz <groug@kaod.org> Message-Id: <159430264541.389456.11925072456012783045.stgit@bahia.lan> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14block: Add support to warn on backing file change without formatEric Blake
For now, this is a mechanical addition; all callers pass false. But the next patch will use it to improve 'qemu-img rebase -u' when selecting a backing file with no format. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Peter Krempa <pkrempa@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Message-Id: <20200706203954.341758-10-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14qcow2: Deprecate use of qemu-img amend to change backing fileEric Blake
The use of 'qemu-img amend' to change qcow2 backing files is not tested very well. In particular, our implementation has a bug where if a new backing file is provided without a format, then the prior format is blindly reused, even if this results in data corruption, but this is not caught by iotests. There are also situations where amending other options needs access to the original backing file (for example, on a downgrade to a v2 image, knowing whether a v3 zero cluster must be allocated or may be left unallocated depends on knowing whether the backing file already reads as zero), but the command line does not have a nice way to tell us both the backing file to use for opening the image as well as the backing file to install after the operation is complete. Even if we do allow changing the backing file, it is redundant with the existing ability to change backing files via 'qemu-img rebase -u'. It is time to deprecate this support (leaving the existing behavior intact, even if it is buggy), and at a point in the future, require the use of only 'qemu-img rebase' for adjusting backing chain relations, saving 'qemu-img amend' for changes unrelated to the backing chain. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200706203954.341758-8-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14qcow: Tolerate backing_fmt=Eric Blake
qcow has no space in the metadata to store a backing format, and there are existing qcow images backed both by raw or by other formats (usually qcow) images, reliant on probing to tell the difference. On the bright side, because we probe every time, raw files are marked as probed and we thus forbid a commit action into the backing file where guest-controlled contents could change the result of the probe next time around (the iotest added here proves that). Still, allowing the user to specify the backing format during creation, even if we can't record it, is a good thing. This patch blindly allows any value that resolves to a known driver, even if the user's request is a mismatch from what probing finds; then the next patch will further enhance things to verify that the user's request matches what we actually probe. With this and the next patch in place, we will finally be ready to deprecate the creation of images where a backing format was not explicitly specified by the user. Note that this is only for QemuOpts usage; there is no change to the QAPI to allow a format through -blockdev. Add a new iotest 301 just for qcow, to demonstrate the latest behavior, and to make it easier to show the improvements made in the next patch. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200706203954.341758-6-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14vmdk: Add trivial backing_fmt supportEric Blake
vmdk already requires that if backing_file is present, that it be another vmdk image (see vmdk_co_do_create). Meanwhile, we want to move towards always being explicit about the backing format for other drivers where it matters. So for convenience, make qemu-img create -F vmdk work, while rejecting all other explicit formats (note that this is only for QemuOpts usage; there is no change to the QAPI to allow a format through -blockdev). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200706203954.341758-5-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14sheepdog: Add trivial backing_fmt supportEric Blake
Sheepdog already requires that if backing_file is present, that it be another sheepdog image (see sd_co_create). Meanwhile, we want to move towards always being explicit about the backing format for other drivers where it matters. So for convenience, make qemu-img create -F sheepdog work, while rejecting all other explicit formats (note that this is only for QemuOpts usage; there is no change to the QAPI to allow a format through -blockdev). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200706203954.341758-4-eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-14file-posix: Mitigate file fragmentation with extent size hintsKevin Wolf
Especially when O_DIRECT is used with image files so that the page cache indirection can't cause a merge of allocating requests, the file will fragment on the file system layer, with a potentially very small fragment size (this depends on the requests the guest sent). On Linux, fragmentation can be reduced by setting an extent size hint when creating the file (at least on XFS, it can't be set any more after the first extent has been allocated), basically giving raw files a "cluster size" for allocation. This adds a create option to set the extent size hint, and changes the default from not setting a hint to setting it to 1 MB. The main reason why qcow2 defaults to smaller cluster sizes is that COW becomes more expensive, which is not an issue with raw files, so we can choose a larger size. The tradeoff here is only potentially wasted disk space. For qcow2 (or other image formats) over file-posix, the advantage should even be greater because they grow sequentially without leaving holes, so there won't be wasted space. Setting even larger extent size hints for such images may make sense. This can be done with the new option, but let's keep the default conservative for now. The effect is very visible with a test that intentionally creates a badly fragmented file with qemu-img bench (the time difference while creating the file is already remarkable) and then looks at the number of extents and the time a simple "qemu-img map" takes. Without an extent size hint: $ ./qemu-img create -f raw -o extent_size_hint=0 ~/tmp/test.raw 10G Formatting '/home/kwolf/tmp/test.raw', fmt=raw size=10737418240 extent_size_hint=0 $ ./qemu-img bench -f raw -t none -n -w ~/tmp/test.raw -c 1000000 -S 8192 -o 0 Sending 1000000 write requests, 4096 bytes each, 64 in parallel (starting at offset 0, step size 8192) Run completed in 25.848 seconds. $ ./qemu-img bench -f raw -t none -n -w ~/tmp/test.raw -c 1000000 -S 8192 -o 4096 Sending 1000000 write requests, 4096 bytes each, 64 in parallel (starting at offset 4096, step size 8192) Run completed in 19.616 seconds. $ filefrag ~/tmp/test.raw /home/kwolf/tmp/test.raw: 2000000 extents found $ time ./qemu-img map ~/tmp/test.raw Offset Length Mapped to File 0 0x1e8480000 0 /home/kwolf/tmp/test.raw real 0m1,279s user 0m0,043s sys 0m1,226s With the new default extent size hint of 1 MB: $ ./qemu-img create -f raw -o extent_size_hint=1M ~/tmp/test.raw 10G Formatting '/home/kwolf/tmp/test.raw', fmt=raw size=10737418240 extent_size_hint=1048576 $ ./qemu-img bench -f raw -t none -n -w ~/tmp/test.raw -c 1000000 -S 8192 -o 0 Sending 1000000 write requests, 4096 bytes each, 64 in parallel (starting at offset 0, step size 8192) Run completed in 11.833 seconds. $ ./qemu-img bench -f raw -t none -n -w ~/tmp/test.raw -c 1000000 -S 8192 -o 4096 Sending 1000000 write requests, 4096 bytes each, 64 in parallel (starting at offset 4096, step size 8192) Run completed in 10.155 seconds. $ filefrag ~/tmp/test.raw /home/kwolf/tmp/test.raw: 178 extents found $ time ./qemu-img map ~/tmp/test.raw Offset Length Mapped to File 0 0x1e8480000 0 /home/kwolf/tmp/test.raw real 0m0,061s user 0m0,040s sys 0m0,014s Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20200707142329.48303-1-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-07-13nbd: Avoid off-by-one in long export name truncationEric Blake
When snprintf returns the same value as the buffer size, the final byte was truncated to ensure a NUL terminator. Fortunately, such long export names are unusual enough, with no real impact other than what is displayed to the user. Fixes: 5c86bdf12089 Reported-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200622210355.414941-1-eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
2020-07-10iscsi: return -EIO when sense fields are meaninglessXie Yongji
When an I/O request failed, now we only return correct value on scsi check condition. We should also have a default errno such as -EIO in other case. Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Message-Id: <20200701105444.3226-2-xieyongji@bytedance.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10iscsi: handle check condition status in retry loopXie Yongji
The handling of check condition was incorrect because we would only do it after retries exceed maximum. Fixes: 8c460269aa ("iscsi: base all handling of check condition on scsi_sense_to_errno") Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Message-Id: <20200701105444.3226-1-xieyongji@bytedance.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10nbd: Use ERRP_GUARD()Vladimir Sementsov-Ogievskiy
If we want to check error after errp-function call, we need to introduce local_err and then propagate it to errp. Instead, use the ERRP_GUARD() macro, benefits are: 1. No need of explicit error_propagate call 2. No need of explicit local_err variable: use errp directly 3. ERRP_GUARD() leaves errp as is if it's not NULL or &error_fatal, this means that we don't break error_abort (we'll abort on error_set, not on error_propagate) If we want to add some info to errp (by error_prepend() or error_append_hint()), we must use the ERRP_GUARD() macro. Otherwise, this info will not be added when errp == &error_fatal (the program will exit prior to the error_append_hint() or error_prepend() call). Fix several such cases, e.g. in nbd_read(). This commit is generated by command sed -n '/^Network Block Device (NBD)$/,/^$/{s/^F: //p}' \ MAINTAINERS | \ xargs git ls-files | grep '\.[hc]$' | \ xargs spatch \ --sp-file scripts/coccinelle/errp-guard.cocci \ --macro-file scripts/cocci-macro-file.h \ --in-place --no-show-diff --max-width 80 Reported-by: Kevin Wolf <kwolf@redhat.com> Reported-by: Greg Kurz <groug@kaod.org> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Commit message tweaked] Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20200707165037.1026246-8-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> [ERRP_AUTO_PROPAGATE() renamed to ERRP_GUARD(), and auto-propagated-errp.cocci to errp-guard.cocci. Commit message tweaked again.]
2020-07-10error: Avoid error_propagate() after migrate_add_blocker()Markus Armbruster
When migrate_add_blocker(blocker, &errp) is followed by error_propagate(errp, err), we can often just as well do migrate_add_blocker(..., errp). Do that with this Coccinelle script: @@ expression blocker, err, errp; expression ret; @@ - ret = migrate_add_blocker(blocker, &err); - if (err) { + ret = migrate_add_blocker(blocker, errp); + if (ret < 0) { ... when != err; - error_propagate(errp, err); ... } @@ expression blocker, err, errp; @@ - migrate_add_blocker(blocker, &err); - if (err) { + if (migrate_add_blocker(blocker, errp) < 0) { ... when != err; - error_propagate(errp, err); ... } Double-check @err is not used afterwards. Dereferencing it would be use after free, but checking whether it's null would be legitimate. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200707160613.848843-43-armbru@redhat.com>
2020-07-10qapi: Smooth another visitor error checking patternMarkus Armbruster
Convert visit_type_FOO(v, ..., &ptr, &err); ... if (err) { ... } to visit_type_FOO(v, ..., &ptr, errp); ... if (!ptr) { ... } for functions that set @ptr to non-null / null on success / error. Eliminate error_propagate() that are now unnecessary. Delete @err that are now unused. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-40-armbru@redhat.com>
2020-07-10block/parallels: Simplify parallels_open() after previous commitMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200707160613.848843-39-armbru@redhat.com>
2020-07-10error: Reduce unnecessary error propagationMarkus Armbruster
When all we do with an Error we receive into a local variable is propagating to somewhere else, we can just as well receive it there right away, even when we need to keep error_propagate() for other error paths. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-38-armbru@redhat.com>
2020-07-10error: Eliminate error_propagate() manuallyMarkus Armbruster
When all we do with an Error we receive into a local variable is propagating to somewhere else, we can just as well receive it there right away. The previous two commits did that for sufficiently simple cases with Coccinelle. Do it for several more manually. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-37-armbru@redhat.com>
2020-07-10error: Eliminate error_propagate() with Coccinelle, part 2Markus Armbruster
When all we do with an Error we receive into a local variable is propagating to somewhere else, we can just as well receive it there right away. The previous commit did that with a Coccinelle script I consider fairly trustworthy. This commit uses the same script with the matching of return taken out, i.e. we convert if (!foo(..., &err)) { ... error_propagate(errp, err); ... } to if (!foo(..., errp)) { ... ... } This is unsound: @err could still be read between afterwards. I don't know how to express "no read of @err without an intervening write" in Coccinelle. Instead, I manually double-checked for uses of @err. Suboptimal line breaks tweaked manually. qdev_realize() simplified further to placate scripts/checkpatch.pl. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-36-armbru@redhat.com>
2020-07-10error: Eliminate error_propagate() with Coccinelle, part 1Markus Armbruster
When all we do with an Error we receive into a local variable is propagating to somewhere else, we can just as well receive it there right away. Convert if (!foo(..., &err)) { ... error_propagate(errp, err); ... return ... } to if (!foo(..., errp)) { ... ... return ... } where nothing else needs @err. Coccinelle script: @rule1 forall@ identifier fun, err, errp, lbl; expression list args, args2; binary operator op; constant c1, c2; symbol false; @@ if ( ( - fun(args, &err, args2) + fun(args, errp, args2) | - !fun(args, &err, args2) + !fun(args, errp, args2) | - fun(args, &err, args2) op c1 + fun(args, errp, args2) op c1 ) ) { ... when != err when != lbl: when strict - error_propagate(errp, err); ... when != err ( return; | return c2; | return false; ) } @rule2 forall@ identifier fun, err, errp, lbl; expression list args, args2; expression var; binary operator op; constant c1, c2; symbol false; @@ - var = fun(args, &err, args2); + var = fun(args, errp, args2); ... when != err if ( ( var | !var | var op c1 ) ) { ... when != err when != lbl: when strict - error_propagate(errp, err); ... when != err ( return; | return c2; | return false; | return var; ) } @depends on rule1 || rule2@ identifier err; @@ - Error *err = NULL; ... when != err Not exactly elegant, I'm afraid. The "when != lbl:" is necessary to avoid transforming if (fun(args, &err)) { goto out } ... out: error_propagate(errp, err); even though other paths to label out still need the error_propagate(). For an actual example, see sclp_realize(). Without the "when strict", Coccinelle transforms vfio_msix_setup(), incorrectly. I don't know what exactly "when strict" does, only that it helps here. The match of return is narrower than what I want, but I can't figure out how to express "return where the operand doesn't use @err". For an example where it's too narrow, see vfio_intx_enable(). Silently fails to convert hw/arm/armsse.c, because Coccinelle gets confused by ARMSSE being used both as typedef and function-like macro there. Converted manually. Line breaks tidied up manually. One nested declaration of @local_err deleted manually. Preexisting unwanted blank line dropped in hw/riscv/sifive_e.c. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10error: Avoid unnecessary error_propagate() after error_setg()Markus Armbruster
Replace error_setg(&err, ...); error_propagate(errp, err); by error_setg(errp, ...); Related pattern: if (...) { error_setg(&err, ...); goto out; } ... out: error_propagate(errp, err); return; When all paths to label out are that way, replace by if (...) { error_setg(errp, ...); return; } and delete the label along with the error_propagate(). When we have at most one other path that actually needs to propagate, and maybe one at the end that where propagation is unnecessary, e.g. foo(..., &err); if (err) { goto out; } ... bar(..., &err); out: error_propagate(errp, err); return; move the error_propagate() to where it's needed, like if (...) { foo(..., &err); error_propagate(errp, err); return; } ... bar(..., errp); return; and transform the error_setg() as above. In some places, the transformation results in obviously unnecessary error_propagate(). The next few commits will eliminate them. Bonus: the elimination of gotos will make later patches in this series easier to review. Candidates for conversion tracked down with this Coccinelle script: @@ identifier err, errp; expression list args; @@ - error_setg(&err, args); + error_setg(errp, args); ... when != err error_propagate(errp, err); Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200707160613.848843-34-armbru@redhat.com>
2020-07-10qapi: Use returned bool to check for failure, manual partMarkus Armbruster
The previous commit used Coccinelle to convert from checking the Error object to checking the return value. Convert a few more manually. Also tweak control flow in places to conform to the conventional "if error bail out" pattern. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200707160613.848843-20-armbru@redhat.com>
2020-07-10qapi: Use returned bool to check for failure, Coccinelle partMarkus Armbruster
The previous commit enables conversion of visit_foo(..., &err); if (err) { ... } to if (!visit_foo(..., errp)) { ... } for visitor functions that now return true / false on success / error. Coccinelle script: @@ identifier fun =~ "check_list|input_type_enum|lv_start_struct|lv_type_bool|lv_type_int64|lv_type_str|lv_type_uint64|output_type_enum|parse_type_bool|parse_type_int64|parse_type_null|parse_type_number|parse_type_size|parse_type_str|parse_type_uint64|print_type_bool|print_type_int64|print_type_null|print_type_number|print_type_size|print_type_str|print_type_uint64|qapi_clone_start_alternate|qapi_clone_start_list|qapi_clone_start_struct|qapi_clone_type_bool|qapi_clone_type_int64|qapi_clone_type_null|qapi_clone_type_number|qapi_clone_type_str|qapi_clone_type_uint64|qapi_dealloc_start_list|qapi_dealloc_start_struct|qapi_dealloc_type_anything|qapi_dealloc_type_bool|qapi_dealloc_type_int64|qapi_dealloc_type_null|qapi_dealloc_type_number|qapi_dealloc_type_str|qapi_dealloc_type_uint64|qobject_input_check_list|qobject_input_check_struct|qobject_input_start_alternate|qobject_input_start_list|qobject_input_start_struct|qobject_input_type_any|qobject_input_type_bool|qobject_input_type_bool_keyval|qobject_input_type_int64|qobject_input_type_int64_keyval|qobject_input_type_null|qobject_input_type_number|qobject_input_type_number_keyval|qobject_input_type_size_keyval|qobject_input_type_str|qobject_input_type_str_keyval|qobject_input_type_uint64|qobject_input_type_uint64_keyval|qobject_output_start_list|qobject_output_start_struct|qobject_output_type_any|qobject_output_type_bool|qobject_output_type_int64|qobject_output_type_null|qobject_output_type_number|qobject_output_type_str|qobject_output_type_uint64|start_list|visit_check_list|visit_check_struct|visit_start_alternate|visit_start_list|visit_start_struct|visit_type_.*"; expression list args; typedef Error; Error *err; @@ - fun(args, &err); - if (err) + if (!fun(args, &err)) { ... } A few line breaks tidied up manually. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20200707160613.848843-19-armbru@redhat.com>
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-18 18:57:09 +0000