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2023-02-01block: Convert bdrv_get_allocated_file_size() to co_wrapperEmanuele Giuseppe Esposito
bdrv_get_allocated_file_size() is categorized as an I/O function, and it currently doesn't run in a coroutine. We should let it take a graph rdlock since it traverses the block nodes graph, which however is only possible in a coroutine. Therefore turn it into a co_wrapper to move the actual function into a coroutine where the lock can be taken. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-10-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_refresh_total_sectors() to co_wrapper_mixedEmanuele Giuseppe Esposito
BlockDriver->bdrv_getlength is categorized as IO callback, and it currently doesn't run in a coroutine. We should let it take a graph rdlock since the callback traverses the block nodes graph, which however is only possible in a coroutine. Therefore turn it into a co_wrapper to move the actual function into a coroutine where the lock can be taken. Because now this function creates a new coroutine and polls, we need to take the AioContext lock where it is missing, for the only reason that internally co_wrapper calls AIO_WAIT_WHILE and it expects to release the AioContext lock. This is especially messy when a co_wrapper creates a coroutine and polls in bdrv_open_driver, because this function has so many callers in so many context that it can easily lead to deadlocks. Therefore the new rule for bdrv_open_driver is that the caller must always hold the AioContext lock of the given bs (except if it is a coroutine), because the function calls bdrv_refresh_total_sectors() which is now a co_wrapper. Once the rwlock is ultimated and placed in every place it needs to be, we will poll using AIO_WAIT_WHILE_UNLOCKED and remove the AioContext lock. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-7-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-01-20include/block: Untangle inclusion loopsMarkus Armbruster
We have two inclusion loops: block/block.h -> block/block-global-state.h -> block/block-common.h -> block/blockjob.h -> block/block.h block/block.h -> block/block-io.h -> block/block-common.h -> block/blockjob.h -> block/block.h I believe these go back to Emanuele's reorganization of the block API, merged a few months ago in commit d7e2fe4aac8. Fortunately, breaking them is merely a matter of deleting unnecessary includes from headers, and adding them back in places where they are now missing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221221133551.3967339-2-armbru@redhat.com>
2021-09-29block: use int64_t instead of uint64_t in driver write handlersVladimir Sementsov-Ogievskiy
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>
2021-09-29block: use int64_t instead of uint64_t in driver read handlersVladimir Sementsov-Ogievskiy
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 read 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_\(aio\|co\)_preadv\(_part\)\?' shows that's there three callers of driver function: bdrv_driver_preadv() in block/io.c, passes int64_t, checked by bdrv_check_qiov_request() to be non-negative. qcow2_load_vmstate() does bdrv_check_qiov_request(). do_perform_cow_read() has uint64_t argument. And a lot of things in qcow2 driver are uint64_t, so converting it is big job. But we must not work with requests that don't satisfy bdrv_check_qiov_request(), so let's just assert it here. Still, the functions may be called directly, not only by drv->... Let's check: git grep '\.bdrv_\(aio\|co\)_preadv\(_part\)\?\s*=' | \ awk '{print $4}' | sed 's/,//' | sed 's/&//' | sort | uniq | \ while read func; do git grep "$func(" | \ grep -v "$func(BlockDriverState"; done The only one such caller: QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, &data, 1); ... ret = bdrv_replace_test_co_preadv(bs, 0, 1, &qiov, 0); in tests/unit/test-bdrv-drain.c, and it's OK obviously. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Message-Id: <20210903102807.27127-4-vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> [eblake: fix typos] Signed-off-by: Eric Blake <eblake@redhat.com>
2020-09-07block/null: Implement bdrv_get_allocated_file_sizeMax Reitz
It is trivial, so we might as well do it. Remove _filter_actual_image_size from iotest 184, so we get to see the result in its reference output. Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-14replay: add BH oneshot event for block layerPavel Dovgalyuk
Replay is capable of recording normal BH events, but sometimes there are single use callbacks scheduled with aio_bh_schedule_oneshot function. This patch enables recording and replaying such callbacks. Block layer uses these events for calling the completion function. Replaying these calls makes the execution deterministic. Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru> Acked-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-12Include qemu/module.h where needed, drop it from qemu-common.hMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20190523143508.25387-4-armbru@redhat.com> [Rebased with conflicts resolved automatically, except for hw/usb/dev-hub.c hw/misc/exynos4210_rng.c hw/misc/bcm2835_rng.c hw/misc/aspeed_scu.c hw/display/virtio-vga.c hw/arm/stm32f205_soc.c; ui/cocoa.m fixed up]
2019-02-25block/null: Generate filename even with latency-nsMax Reitz
While we cannot represent the latency-ns option in a filename, it is not a strong option so not being able to should not stop us from generating a filename nonetheless. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20190201192935.18394-30-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-02-25block: Purify .bdrv_refresh_filename()Max Reitz
Currently, BlockDriver.bdrv_refresh_filename() is supposed to both refresh the filename (BDS.exact_filename) and set BDS.full_open_options. Now that we have generic code in the central bdrv_refresh_filename() for creating BDS.full_open_options, we can drop the latter part from all BlockDriver.bdrv_refresh_filename() implementations. This also means that we can drop all of the existing default code for this from the global bdrv_refresh_filename() itself. Furthermore, we now have to call BlockDriver.bdrv_refresh_filename() after having set BDS.full_open_options, because the block driver's implementation should now be allowed to depend on BDS.full_open_options being set correctly. Finally, with this patch we can drop the @options parameter from BlockDriver.bdrv_refresh_filename(); also, add a comment on this function's purpose in block/block_int.h while touching its interface. This completely obsoletes blklogwrite's implementation of .bdrv_refresh_filename(). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190201192935.18394-25-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-02-25block: Add strong_runtime_opts to BlockDriverMax Reitz
This new field can be set by block drivers to list the runtime options they accept that may influence the contents of the respective BDS. As of a follow-up patch, this list will be used by the common bdrv_refresh_filename() implementation to decide which options to put into BDS.full_open_options (and consequently whether a JSON filename has to be created), thus freeing the drivers of having to implement that logic themselves. Additionally, this patch adds the field to all of the block drivers that need it and sets it accordingly. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20190201192935.18394-22-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2018-08-15block: drop empty .bdrv_close handlersVladimir Sementsov-Ogievskiy
.bdrv_close handler is optional after previous commit, no needs to keep empty functions more. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-15null: Switch to byte-based read/writeEric Blake
We are gradually moving away from sector-based interfaces, towards byte-based. Make the change for the last few sector-based callbacks in the null-co and null-aio drivers. Note that since the null driver does nothing on writes, it trivially supports the BDRV_REQ_FUA flag (all writes have already landed to the same bit-bucket without needing an extra flush call). Also, since the null driver does just as well with byte-based requests, we can now avoid cycles wasted on read-modify-write by taking advantage of the block layer now defaulting the alignment to 1 instead of 512. Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-05-04qobject: Modify qobject_ref() to return objMarc-André Lureau
For convenience and clarity, make it possible to call qobject_ref() at the time when the reference is associated with a variable, or argument, by making qobject_ref() return the same pointer as given. Use that to simplify the callers. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20180419150145.24795-5-marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Useless change to qobject_ref_impl() dropped, commit message improved slightly] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-05-04qobject: Replace qobject_incref/QINCREF qobject_decref/QDECREFMarc-André Lureau
Now that we can safely call QOBJECT() on QObject * as well as its subtypes, we can have macros qobject_ref() / qobject_unref() that work everywhere instead of having to use QINCREF() / QDECREF() for QObject and qobject_incref() / qobject_decref() for its subtypes. The replacement is mechanical, except I broke a long line, and added a cast in monitor_qmp_cleanup_req_queue_locked(). Unlike qobject_decref(), qobject_unref() doesn't accept void *. Note that the new macros evaluate their argument exactly once, thus no need to shout them. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20180419150145.24795-4-marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Rebased, semantic conflict resolved, commit message improved] Signed-off-by: Markus Armbruster <armbru@redhat.com>
2018-03-02null: Switch to .bdrv_co_block_status()Eric Blake
We are gradually moving away from sector-based interfaces, towards byte-based. Update the null driver accordingly. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-02-09Move include qemu/option.h from qemu-common.h to actual usersMarkus Armbruster
qemu-common.h includes qemu/option.h, but most places that include the former don't actually need the latter. Drop the include, and add it to the places that actually need it. While there, drop superfluous includes of both headers, and separate #include from file comment with a blank line. This cleanup makes the number of objects depending on qemu/option.h drop from 4545 (out of 4743) to 284 in my "build everything" tree. Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20180201111846.21846-20-armbru@redhat.com> [Semantic conflict with commit bdd6a90a9e in block/nvme.c resolved]
2017-12-19coroutine: simplify co_aio_sleep_ns() prototypeStefan Hajnoczi
The AioContext pointer argument to co_aio_sleep_ns() is only used for the sleep timer. It does not affect where the caller coroutine is resumed. Due to changes to coroutine and AIO APIs it is now possible to drop the AioContext pointer argument. This is safe to do since no caller has specific requirements for which AioContext the timer must run in. This patch drops the AioContext pointer argument and renames the function to simplify the API. Reported-by: Paolo Bonzini <pbonzini@redhat.com> Reported-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 20171109102652.6360-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-08-08block/null: Remove 'filename' optionKevin Wolf
This option was only added to allow 'null-co://' and 'null-aio://' as filenames, its value never served any actual purpose and was ignored. Nevertheless it was accepted as '-drive driver=null,filename=foo'. The correct way to enable the protocol prefixes (and that without adding a useless -drive option) is implementing .bdrv_parse_filename. This is what this patch does. Technically, this is an incompatible change, but the null block driver is only used for benchmarking, testing and debugging, and an option without effect isn't likely to be used by anyone anyway, so no bad effects are to be expected. Reported-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-05-09qobject: Use simpler QDict/QList scalar insertion macrosEric Blake
We now have macros in place to make it less verbose to add a scalar to QDict and QList, so use them. Patch created mechanically via: spatch --sp-file scripts/coccinelle/qobject.cocci \ --macro-file scripts/cocci-macro-file.h --dir . --in-place then touched up manually to fix a couple of '?:' back to original spacing, as well as avoiding a long line in monitor.c. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20170427215821.19397-7-eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-10-07block: use aio_bh_schedule_oneshotPaolo Bonzini
This simplifies bottom half handlers by removing calls to qemu_bh_delete and thus removing the need to stash the bottom half pointer in the opaque datum. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-06-16block/null: Implement bdrv_refresh_filename()Max Reitz
The null block driver ignores any filename used for creating its BDSs, which allows creating such BDSs even without any filename at all. In that case, we currently construct a JSON filename when queried instead of a plain "null-co://" or "null-aio://". This patch implements bdrv_refresh_filename() to remedy this behavior. Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20160610185750.30956-4-mreitz@redhat.com [mreitz@redhat.com: Added commit message] Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-03-30block/null-{co,aio}: Implement get_block_status()Max Reitz
Signed-off-by: Max Reitz <mreitz@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-30block/null-{co,aio}: Allow reading zeroesMax Reitz
This is optional so that it does not impede the null block driver's performance unless this behavior is desired. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Acked-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-22include/qemu/osdep.h: Don't include qapi/error.hMarkus Armbruster
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the Error typedef. Since then, we've moved to include qemu/osdep.h everywhere. Its file comment explains: "To avoid getting into possible circular include dependencies, this file should not include any other QEMU headers, with the exceptions of config-host.h, compiler.h, os-posix.h and os-win32.h, all of which are doing a similar job to this file and are under similar constraints." qapi/error.h doesn't do a similar job, and it doesn't adhere to similar constraints: it includes qapi-types.h. That's in excess of 100KiB of crap most .c files don't actually need. Add the typedef to qemu/typedefs.h, and include that instead of qapi/error.h. Include qapi/error.h in .c files that need it and don't get it now. Include qapi-types.h in qom/object.h for uint16List. Update scripts/clean-includes accordingly. Update it further to match reality: replace config.h by config-target.h, add sysemu/os-posix.h, sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h comment quoted above similarly. This reduces the number of objects depending on qapi/error.h from "all of them" to less than a third. Unfortunately, the number depending on qapi-types.h shrinks only a little. More work is needed for that one. Signed-off-by: Markus Armbruster <armbru@redhat.com> [Fix compilation without the spice devel packages. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-20block: Clean up includesPeter Maydell
Clean up includes so that osdep.h is included first and headers which it implies are not included manually. This commit was created with scripts/clean-includes. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/null: Support reopenFam Zheng
Reopen is used in block-commit. With this always-succeed operation, it is now possible to test committing to a null drive, by specifying "null-aio://" or "null-co://" as the backing image when creating the qcow2 image. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1427852740-24315-3-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2015-04-28block/null: Latency simulation by adding new option "latency-ns"Fam Zheng
Aio context switch should just work because the requests will be drained, so the scheduled timer(s) on the old context will be freed. Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1427852740-24315-2-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Rename BlockDriverCompletionFunc to BlockCompletionFuncMarkus Armbruster
I'll use it with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-10-20block: Rename BlockDriverAIOCB* to BlockAIOCB*Markus Armbruster
I'll use BlockDriverAIOCB with block backends shortly, and the name is going to fit badly there. It's a block layer thing anyway, not just a block driver thing. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-09-22block: Introduce "null" driversFam Zheng
This is an analogue to Linux null_blk. It can be used for testing or benchmarking block device emulation and general block layer functionalities such as coroutines and throttling, where disk IO is not necessary or wanted. Use null-aio:// for AIO version, and null-co:// for coroutine version. [Resolved conflict with Fam's async bdrv_aio_cancel() series: 1. Drop .bdrv_aio_cancel() since it is now done by block.c 2. Rename qemu_aio_release() to qemu_aio_unref() --Stefan] Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1410415798-20673-2-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>