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2023-02-01block: Rename bdrv_load/save_vmstate() to bdrv_co_load/save_vmstate()Emanuele Giuseppe Esposito1-4/+4
Since these functions always run in coroutine context, adjust their name to include "_co_", just like all other BlockDriver callbacks. No functional change intended. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-15-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_debug_event() to co_wrapper_mixedEmanuele Giuseppe Esposito1-11/+11
bdrv_debug_event() 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_mixed 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: <20230113204212.359076-14-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_get_info() to co_wrapper_mixedEmanuele Giuseppe Esposito1-4/+4
bdrv_get_info() 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: <20230113204212.359076-11-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: use bdrv_co_refresh_total_sectors when possibleEmanuele Giuseppe Esposito1-2/+2
In some places we are sure we are always running in a coroutine, therefore it's useless to call the generated_co_wrapper, instead call directly the _co_ function. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-9-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Rename refresh_total_sectors to bdrv_refresh_total_sectorsEmanuele Giuseppe Esposito1-3/+5
The name is not good, not the least because we are going to convert this to a generated co_wrapper, which adds a _co infix after the first part of the name. No functional change intended. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230113204212.359076-6-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_is_inserted() to co_wrapperEmanuele Giuseppe Esposito1-6/+6
bdrv_is_inserted() 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. At the same time, add also blk_is_inserted as co_wrapper_mixed, since it is called in both coroutine and non-coroutine contexts. 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 c_w_mixed_bdrv_rdlock calls AIO_WAIT_WHILE and it expects to release the AioContext lock. 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: <20230113204212.359076-5-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_io_unplug() to co_wrapperEmanuele Giuseppe Esposito1-4/+4
BlockDriver->bdrv_io_unplug 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. The only caller of this function is blk_io_unplug(), therefore make blk_io_unplug() a co_wrapper, so that we're always running in 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: <20230113204212.359076-4-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_io_plug() to co_wrapperEmanuele Giuseppe Esposito1-4/+4
BlockDriver->bdrv_io_plug 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. The only caller of this function is blk_io_plug(), therefore make blk_io_plug() a co_wrapper, so that we're always running in 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: <20230113204212.359076-3-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 Armbruster1-0/+1
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>
2022-12-21block/io: Check for replay-enabled in bdrv_drain_all_begin()Peter Maydell1-0/+9
In commit da0bd74434 we refactored bdrv_drain_all_begin() to pull out the non-polling part into bdrv_drain_all_begin_nopoll(). This change broke record-and-replay, because the "return early if replay enabled" check is now in the sub-function bdrv_drain_all_begin_nopoll(), and so it only causes us to return from that function, and not from the calling bdrv_drain_all_begin(). Fix the regression by checking whether replay is enabled in both functions. The breakage and fix can be tested via 'make check-avocado': the tests/avocado/reverse_debugging.py:ReverseDebugging_X86_64.test_x86_64_pc tests/avocado/reverse_debugging.py:ReverseDebugging_AArch64.test_aarch64_virt tests were both broken by this. Fixes: da0bd744344adb1f285 ("block: Factor out bdrv_drain_all_begin_nopoll()") Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Tested-by: Fabiano Rosas <farosas@suse.de> Message-id: 20221220174638.2156308-1-peter.maydell@linaro.org
2022-12-15block: GRAPH_RDLOCK for functions only called by co_wrappersKevin Wolf1-0/+2
The generated coroutine wrappers already take care to take the lock in the non-coroutine path, and assume that the lock is already taken in the coroutine path. The only thing we need to do for the wrapped function is adding the GRAPH_RDLOCK annotation. Doing so also allows us to mark the corresponding callbacks in BlockDriver as GRAPH_RDLOCK_PTR. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-19-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Factor out bdrv_drain_all_begin_nopoll()Kevin Wolf1-6/+13
Provide a separate function that just quiesces the users of a node to prevent new requests from coming in, but without waiting for the already in-flight I/O to complete. This function can be used in contexts where polling is not allowed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221207131838.239125-2-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block-io: introduce coroutine_fn duplicates for ↵Emanuele Giuseppe Esposito1-3/+55
bdrv_common_block_status_above callers bdrv_common_block_status_above() is a g_c_w, and it is being called by many "wrapper" functions like bdrv_is_allocated(), bdrv_is_allocated_above() and bdrv_block_status_above(). Because we want to eventually split the coroutine from non-coroutine case in g_c_w, create duplicate wrappers that take care of directly calling the same coroutine functions called in the g_c_w. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20221128142337.657646-2-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Remove poll parameter from bdrv_parent_drained_begin_single()Kevin Wolf1-6/+2
All callers of bdrv_parent_drained_begin_single() pass poll=false now, so we don't need the parameter any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-16-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Don't poll in bdrv_replace_child_noperm()Kevin Wolf1-1/+1
In order to make sure that bdrv_replace_child_noperm() doesn't have to poll any more, get rid of the bdrv_parent_drained_begin_single() call. This is possible now because we can require that the parent is already drained through the child in question when the function is called and we don't call the parent drain callbacks more than once. The additional drain calls needed in callers cause the test case to run its code in the drain handler too early (bdrv_attach_child() drains now), so modify it to only enable the code after the test setup has completed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-15-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Drop out of coroutine in bdrv_do_drained_begin_quiesce()Kevin Wolf1-13/+12
The next patch adds a parent drain to bdrv_attach_child_common(), which shouldn't be, but is currently called from coroutines in some cases (e.g. .bdrv_co_create implementations generally open new nodes). Therefore, the assertion that we're not in a coroutine doesn't hold true any more. We could just remove the assertion because there is nothing in the function that should be in conflict with running in a coroutine, but just to be on the safe side, we can reverse the caller relationship between bdrv_do_drained_begin() and bdrv_do_drained_begin_quiesce() so that the latter also just drops out of coroutine context and we can still be certain in the future that any drain code doesn't run in coroutines. As a nice side effect, the structure of bdrv_do_drained_begin() is now symmetrical with bdrv_do_drained_end(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-14-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Remove ignore_bds_parents parameter from drain_begin/end.Kevin Wolf1-36/+22
ignore_bds_parents is now ignored during drain_begin and drain_end, so we can just remove it there. It is still a valid optimisation for drain_all in bdrv_drained_poll(), so leave it around there. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20221118174110.55183-13-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Call drain callbacks only onceKevin Wolf1-12/+18
We only need to call both the BlockDriver's callback and the parent callbacks when going from undrained to drained or vice versa. A second drain section doesn't make a difference for the driver or the parent, they weren't supposed to send new requests before and after the second drain. One thing that gets in the way is the 'ignore_bds_parents' parameter in bdrv_do_drained_begin_quiesce() and bdrv_do_drained_end(): It means that bdrv_drain_all_begin() increases bs->quiesce_counter, but does not quiesce the parent through BdrvChildClass callbacks. If an additional drain section is started now, bs->quiesce_counter will be non-zero, but we would still need to quiesce the parent through BdrvChildClass in order to keep things consistent (and unquiesce it on the matching bdrv_drained_end(), even though the counter would not reach 0 yet as long as the bdrv_drain_all() section is still active). Instead of keeping track of this, let's just get rid of the parameter. It was introduced in commit 6cd5c9d7b2d as an optimisation so that during bdrv_drain_all(), we wouldn't recursively drain all parents up to the root for each node, resulting in quadratic complexity. As it happens, calling the callbacks only once solves the same problem, so as of this patch, we'll still have O(n) complexity and ignore_bds_parents is not needed any more. This patch only ignores the 'ignore_bds_parents' parameter. It will be removed in a separate patch. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-12-kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Remove subtree drainsKevin Wolf1-95/+26
Subtree drains are not used any more. Remove them. After this, BdrvChildClass.attach/detach() don't poll any more. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-11-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Inline bdrv_drain_invoke()Kevin Wolf1-17/+6
bdrv_drain_invoke() has now two entirely separate cases that share no code any more and are selected depending on a bool parameter. Each case has only one caller. Just inline the function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-6-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Remove drained_end_counterKevin Wolf1-74/+24
drained_end_counter is unused now, nobody changes its value any more. It can be removed. In cases where we had two almost identical functions that only differed in whether the caller passes drained_end_counter, or whether they would poll for a local drained_end_counter to reach 0, these become a single function. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Message-Id: <20221118174110.55183-5-kwolf@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-15block: Revert .bdrv_drained_begin/end to non-coroutine_fnKevin Wolf1-42/+7
Polling during bdrv_drained_end() can be problematic (and in the future, we may get cases for bdrv_drained_begin() where polling is forbidden, and we don't care about already in-flight requests, but just want to prevent new requests from arriving). The .bdrv_drained_begin/end callbacks running in a coroutine is the only reason why we have to do this polling, so make them non-coroutine callbacks again. None of the callers actually yield any more. This means that bdrv_drained_end() effectively doesn't poll any more, even if AIO_WAIT_WHILE() loops are still there (their condition is false from the beginning). This is generally not a problem, but in test-bdrv-drain, some additional explicit aio_poll() calls need to be added because the test case wants to verify the final state after BHs have executed. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221118174110.55183-4-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-11-10block: Start/end drain on correct AioContextHanna Reitz1-2/+4
bdrv_parent_drained_{begin,end}_single() are supposed to operate on the parent, not on the child, so they should not attempt to get the context to poll from the child but the parent instead. BDRV_POLL_WHILE(c->bs) does get the context from the child, so we should replace it with AIO_WAIT_WHILE() on the parent's context instead. This problem becomes apparent when bdrv_replace_child_noperm() invokes bdrv_parent_drained_end_single() after removing a child from a subgraph that is in an I/O thread. By the time bdrv_parent_drained_end_single() is called, child->bs is NULL, and so BDRV_POLL_WHILE(c->bs, ...) will poll the main loop instead of the I/O thread; but anything that bdrv_parent_drained_end_single_no_poll() may have scheduled is going to want to run in the I/O thread, but because we poll the main loop, the I/O thread is never unpaused, and nothing is run, resulting in a deadlock. Closes: https://gitlab.com/qemu-project/qemu/-/issues/1215 Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20221107151321.211175-4-hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-30Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into stagingStefan Hajnoczi1-4/+4
Block layer patches - Cleanup bs->backing and bs->file handling - Refactor bdrv_try_set_aio_context using transactions - Changes for improved coroutine_fn consistency - vhost-user-blk: fix the resize crash - io_uring: Use of io_uring_register_ring_fd() led to breakage, revert - vvfat: Fix some problems with r/w mode - Code cleanup - MAINTAINERS: Fold "Block QAPI, monitor, ..." into "Block layer core" # -----BEGIN PGP SIGNATURE----- # # iQJFBAABCAAvFiEE3D3rFZqa+V09dFb+fwmycsiPL9YFAmNazhIRHGt3b2xmQHJl # ZGhhdC5jb20ACgkQfwmycsiPL9ZyTw/8Dfck/SuxfyeLlnQItkjaV4cnqWOU8vHs # 9x0KhlptCs+HXdF/3iicpA0lHojn7mNnbdFGjPRY4E0LriQv91TQ5ycdEmrseFPf # sgeQlgdKCVU/pHjZ2wYarm2pE43Cx85a5xuufmw+7w49dNNZn14l4t+DgviuClVM # nuVaogfZFbYyetre+Qd2TgLl+gJ+0d4o7Zs5lSWLrT8t0L9AGkcWPA7Nrbl6loIE # dOautV4G7jLjuMiCeJZOGcnuRVe3gCQ5rCGBFzzH4DUtz4BmiYx4hd3LMEsP0PMM # CrsfDZS04Ztybl9M7TmJuwkAm1gx1JDMOuJuh18lbJocIOBvhkKKxY2wI5LIdZVI # ZntmU36RowkX+GGu/PYpYyMjBDClJppZCl7vnjyLYsVt6r0Vu6SmlHpJhcRYabhe # 96Kv1LXH9A6+ogKPU3Layw6JGjg01GNr1ALuT7PO3pGto/JshmOuBEJJDucoF84M # 5AfxFCohMROVldwblA6M0eKnlQBgtr5BvtgbV54BBo88VlFJgDJFQn7R09cTFUEo # UwaJoS+nIaiZ0bQQVZhZloVppUaTdVJojzfVRCZZctga96/tu1HSFnGLnbEFpUN3 # KOf+XnVNS6Ro+nPSDf9bMjbIom2JicGFfV+6yMgIoxY/d5UA2dTZfefil4TAlSod # 6PsTgg+jrm8= # =/Fw0 # -----END PGP SIGNATURE----- # gpg: Signature made Thu 27 Oct 2022 14:29:38 EDT # 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 * tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (58 commits) block/block-backend: blk_set_enable_write_cache is IO_CODE monitor: switch to *_co_* functions vmdk: switch to *_co_* functions vhdx: switch to *_co_* functions vdi: switch to *_co_* functions qed: switch to *_co_* functions qcow2: switch to *_co_* functions qcow: switch to *_co_* functions parallels: switch to *_co_* functions mirror: switch to *_co_* functions block: switch to *_co_* functions commit: switch to *_co_* functions vmdk: manually add more coroutine_fn annotations qcow2: manually add more coroutine_fn annotations qcow: manually add more coroutine_fn annotations blkdebug: add missing coroutine_fn annotation for indirect-called functions qcow2: add coroutine_fn annotation for indirect-called functions block: add missing coroutine_fn annotation to BlockDriverState callbacks coroutine-io: add missing coroutine_fn annotation to prototypes coroutine-lock: add missing coroutine_fn annotation to prototypes ... Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-27block: switch to *_co_* functionsAlberto Faria1-2/+2
Signed-off-by: Alberto Faria <afaria@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20221013123711.620631-16-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-27block: remove incorrect coroutine_fn annotationAlberto Faria1-2/+2
Signed-off-by: Alberto Faria <afaria@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20221013123711.620631-3-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-26block: return errors from bdrv_register_buf()Stefan Hajnoczi1-3/+31
Registering an I/O buffer is only a performance optimization hint but it is still necessary to return errors when it fails. Later patches will need to detect errors when registering buffers but an immediate advantage is that error_report() calls are no longer needed in block driver .bdrv_register_buf() functions. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20221013185908.1297568-8-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-26block: add BDRV_REQ_REGISTERED_BUF request flagStefan Hajnoczi1-23/+38
Block drivers may optimize I/O requests accessing buffers previously registered with bdrv_register_buf(). Checking whether all elements of a request's QEMUIOVector are within previously registered buffers is expensive, so we need a hint from the user to avoid costly checks. Add a BDRV_REQ_REGISTERED_BUF request flag to indicate that all QEMUIOVector elements in an I/O request are known to be within previously registered buffers. Always pass the flag through to driver read/write functions. There is little harm in passing the flag to a driver that does not use it. Passing the flag to drivers avoids changes across many block drivers. Filter drivers would need to explicitly support the flag and pass through to their children when the children support it. That's a lot of code changes and it's hard to remember to do that everywhere, leading to silent reduced performance when the flag is accidentally dropped. The only problematic scenario with the approach in this patch is when a driver passes the flag through to internal I/O requests that don't use the same I/O buffer. In that case the hint may be set when it should actually be clear. This is a rare case though so the risk is low. Some drivers have assert(!flags), which no longer works when BDRV_REQ_REGISTERED_BUF is passed in. These assertions aren't very useful anyway since the functions are called almost exclusively by bdrv_driver_preadv/pwritev() so if we get flags handling right there then the assertion is not needed. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20221013185908.1297568-7-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-26block: pass size to bdrv_unregister_buf()Stefan Hajnoczi1-3/+3
The only implementor of bdrv_register_buf() is block/nvme.c, where the size is not needed when unregistering a buffer. This is because util/vfio-helpers.c can look up mappings by address. Future block drivers that implement bdrv_register_buf() may not be able to do their job given only the buffer address. Add a size argument to bdrv_unregister_buf(). Also document the assumptions about bdrv_register_buf()/bdrv_unregister_buf() calls. The same <host, size> values that were given to bdrv_register_buf() must be given to bdrv_unregister_buf(). gcc 11.2.1 emits a spurious warning that img_bench()'s buf_size local variable might be uninitialized, so it's necessary to silence the compiler. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Message-id: 20221013185908.1297568-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2022-10-07block: add missing coroutine_fn annotationsPaolo Bonzini1-11/+11
Callers of coroutine_fn must be coroutine_fn themselves, or the call must be within "if (qemu_in_coroutine())". Apply coroutine_fn to functions where this holds. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20220922084924.201610-3-pbonzini@redhat.com> [kwolf: Fixed up coding style] Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-09-30block: move bdrv_qiov_is_aligned to file-posixKeith Busch1-21/+0
There is only user of bdrv_qiov_is_aligned(), so move the alignment function to there and make it static. Signed-off-by: Keith Busch <kbusch@kernel.org> Message-Id: <20220929200523.3218710-2-kbusch@meta.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-09-30block: make serializing requests functions 'void'Denis V. Lunev1-16/+7
Return codes of the following functions are never used in the code: * bdrv_wait_serialising_requests_locked * bdrv_wait_serialising_requests * bdrv_make_request_serialising Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Kevin Wolf <kwolf@redhat.com> CC: Hanna Reitz <hreitz@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Fam Zheng <fam@euphon.net> CC: Ronnie Sahlberg <ronniesahlberg@gmail.com> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Peter Lieven <pl@kamp.de> CC: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20220817083736.40981-3-den@openvz.org> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-07-12block: Add bdrv_co_pwrite_sync()Alberto Faria1-4/+5
Also convert bdrv_pwrite_sync() to being implemented using generated_co_wrapper. Signed-off-by: Alberto Faria <afaria@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220609152744.3891847-9-afaria@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12block: Implement bdrv_{pread,pwrite,pwrite_zeroes}() using generated_co_wrapperAlberto Faria1-41/+0
bdrv_{pread,pwrite}() now return -EIO instead of -EINVAL when 'bytes' is negative, making them consistent with bdrv_{preadv,pwritev}() and bdrv_co_{pread,pwrite,preadv,pwritev}(). bdrv_pwrite_zeroes() now also calls trace_bdrv_co_pwrite_zeroes() and clears the BDRV_REQ_MAY_UNMAP flag when appropriate, which it didn't previously. Signed-off-by: Alberto Faria <afaria@redhat.com> Message-Id: <20220609152744.3891847-8-afaria@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12block: Make bdrv_{pread,pwrite}() return 0 on successAlberto Faria1-8/+2
They currently return the value of their 'bytes' parameter on success. Make them return 0 instead, for consistency with other I/O functions and in preparation to implement them using generated_co_wrapper. This also makes it clear that short reads/writes are not possible. The few callers that rely on the previous behavior are adjusted accordingly by hand. Signed-off-by: Alberto Faria <afaria@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220609152744.3891847-4-afaria@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12block: Change bdrv_{pread,pwrite,pwrite_sync}() param orderAlberto Faria1-6/+6
Swap 'buf' and 'bytes' around for consistency with bdrv_co_{pread,pwrite}(), and in preparation to implement these functions using generated_co_wrapper. Callers were updated using this Coccinelle script: @@ expression child, offset, buf, bytes, flags; @@ - bdrv_pread(child, offset, buf, bytes, flags) + bdrv_pread(child, offset, bytes, buf, flags) @@ expression child, offset, buf, bytes, flags; @@ - bdrv_pwrite(child, offset, buf, bytes, flags) + bdrv_pwrite(child, offset, bytes, buf, flags) @@ expression child, offset, buf, bytes, flags; @@ - bdrv_pwrite_sync(child, offset, buf, bytes, flags) + bdrv_pwrite_sync(child, offset, bytes, buf, flags) Resulting overly-long lines were then fixed by hand. Signed-off-by: Alberto Faria <afaria@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20220609152744.3891847-3-afaria@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12block: Add a 'flags' param to bdrv_{pread,pwrite,pwrite_sync}()Alberto Faria1-6/+7
For consistency with other I/O functions, and in preparation to implement them using generated_co_wrapper. Callers were updated using this Coccinelle script: @@ expression child, offset, buf, bytes; @@ - bdrv_pread(child, offset, buf, bytes) + bdrv_pread(child, offset, buf, bytes, 0) @@ expression child, offset, buf, bytes; @@ - bdrv_pwrite(child, offset, buf, bytes) + bdrv_pwrite(child, offset, buf, bytes, 0) @@ expression child, offset, buf, bytes; @@ - bdrv_pwrite_sync(child, offset, buf, bytes) + bdrv_pwrite_sync(child, offset, buf, bytes, 0) Resulting overly-long lines were then fixed by hand. Signed-off-by: Alberto Faria <afaria@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Message-Id: <20220609152744.3891847-2-afaria@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-06-24block: drop unused bdrv_co_drain() APIStefan Hajnoczi1-15/+0
bdrv_co_drain() has not been used since commit 9a0cec664eef ("mirror: use bdrv_drained_begin/bdrv_drained_end") in 2016. Remove it so there are fewer drain scenarios to worry about. Use bdrv_drained_begin()/bdrv_drained_end() instead. They are "mixed" functions that can be called from coroutine context. Unlike bdrv_co_drain(), these functions provide control of the length of the drained section, which is usually the right thing. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20220521122714.3837731-1-stefanha@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Alberto Faria <afaria@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-05-12coroutine-lock: qemu_co_queue_restart_all is a coroutine-only qemu_co_enter_allPaolo Bonzini1-1/+1
qemu_co_queue_restart_all is basically the same as qemu_co_enter_all but without a QemuLockable argument. That's perfectly fine, but only as long as the function is marked coroutine_fn. If used outside coroutine context, qemu_co_queue_wait will attempt to take the lock and that is just broken: if you are calling qemu_co_queue_restart_all outside coroutine context, the lock is going to be a QemuMutex which cannot be taken twice by the same thread. The patch adds the marker to qemu_co_queue_restart_all and to its sole non-coroutine_fn caller; it then reimplements the function in terms of qemu_co_enter_all_impl, to remove duplicated code and to clarify that the latter also works in coroutine context. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20220427130830.150180-4-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-04-06Replace qemu_real_host_page variables with inlined functionsMarc-André Lureau1-1/+1
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>
2022-03-08Merge remote-tracking branch ↵Peter Maydell1-0/+1
'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>
2022-03-07osdep: Move memalign-related functions to their own headerPeter Maydell1-0/+1
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
2022-03-07block/io: introduce block driver snapshot-access APIVladimir Sementsov-Ogievskiy1-0/+72
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>
2022-03-07block: fix preallocate filter: don't do unaligned preallocate requestsVladimir Sementsov-Ogievskiy1-0/+4
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>
2022-03-04block: Make bdrv_refresh_limits() non-recursiveHanna Reitz1-4/+0
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>
2022-03-04block/coroutines: I/O and "I/O or GS" APIEmanuele Giuseppe Esposito1-0/+3
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>
2022-03-04IO_CODE and IO_OR_GS_CODE for block_int I/O APIEmanuele Giuseppe Esposito1-0/+13
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>
2022-03-04assertions for block_int global state APIEmanuele Giuseppe Esposito1-0/+1
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>
2022-03-04IO_CODE and IO_OR_GS_CODE for block I/O APIEmanuele Giuseppe Esposito1-2/+41
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>
2022-03-04assertions for block global state APIEmanuele Giuseppe Esposito1-0/+11
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>
generated by cgit v1.1 at 2025-01-02 18:23:25 +0000