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2023-06-28block: use bdrv_co_debug_event in coroutine contextPaolo Bonzini
bdrv_co_debug_event was recently introduced, with bdrv_debug_event becoming a wrapper for use in unknown context. Because most of the time bdrv_debug_event is used on a BdrvChild via the wrapper macro BLKDBG_EVENT, introduce a similar macro BLKDBG_CO_EVENT that calls bdrv_co_debug_event, and switch whenever possible. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20230601115145.196465-13-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-06-28block: use bdrv_co_getlength in coroutine contextPaolo Bonzini
bdrv_co_getlength was recently introduced, with bdrv_getlength becoming a wrapper for use in unknown context. Switch to bdrv_co_getlength when possible. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-ID: <20230601115145.196465-12-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-19block: Call .bdrv_co_create(_opts) unlockedKevin Wolf
These are functions that modify the graph, so they must be able to take a writer lock. This is impossible if they already hold the reader lock. If they need a reader lock for some of their operations, they should take it internally. Many of them go through blk_*(), which will always take the lock itself. Direct calls of bdrv_*() need to take the reader lock. Note that while locking for bdrv_co_*() calls is checked by TSA, this is not the case for the mixed_coroutine_fns bdrv_*(). Holding the lock is still required when they are called from coroutine context like here! This effectively reverts 4ec8df0183, but adds some internal locking instead. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230510203601.418015-2-kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-05-10block: bdrv/blk_co_unref() for calls in coroutine contextKevin Wolf
These functions must not be called in coroutine context, because they need write access to the graph. Cc: qemu-stable@nongnu.org Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-Id: <20230504115750.54437-4-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23block: Mark bdrv_co_create() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_co_create() need to hold a reader lock for the graph. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230203152202.49054-17-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23block: Mark public read/write functions GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_co_pread*/pwrite*() need to hold a reader lock for the graph. For some places, we know that they will hold the lock, but we don't have the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock() with a FIXME comment. These places will be removed once everything is properly annotated. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230203152202.49054-12-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23block: Mark read/write in block/io.c GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_driver_*() need to hold a reader lock for the graph. It doesn't add the annotation to public functions yet. For some places, we know that they will hold the lock, but we don't have the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock() with a FIXME comment. These places will be removed once everything is properly annotated. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230203152202.49054-11-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23block: Mark bdrv_co_block_status() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_co_block_status() need to hold a reader lock for the graph. For some places, we know that they will hold the lock, but we don't have the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock() with a FIXME comment. These places will be removed once everything is properly annotated. Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230203152202.49054-5-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-23block: Mark bdrv_co_truncate() and callers GRAPH_RDLOCKKevin Wolf
This adds GRAPH_RDLOCK annotations to declare that callers of bdrv_co_truncate() need to hold a reader lock for the graph. For some places, we know that they will hold the lock, but we don't have the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock() with a FIXME comment. These places will be removed once everything is properly annotated. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230203152202.49054-4-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-17qcow: Fix .bdrv_co_create(_opts) to open images with no_co_wrapperKevin Wolf
.bdrv_co_create implementations run in a coroutine. Therefore they are not allowed to open images directly. Fix the calls to use the corresponding no_co_wrappers instead. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <20230126172432.436111-6-kwolf@redhat.com> Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com> Reviewed-by: Hanna Czenczek <hreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2023-02-01block: Convert bdrv_get_info() to co_wrapper_mixedEmanuele Giuseppe Esposito
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>
2022-12-15block: bdrv_create_file is a coroutine_fnEmanuele Giuseppe Esposito
It is always called in coroutine_fn callbacks, therefore it can directly call bdrv_co_create(). Rename it to bdrv_co_create_file too. 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: <20221128142337.657646-9-eesposit@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-12-14qapi block: Elide redundant has_FOO in generated CMarkus Armbruster
The has_FOO for pointer-valued FOO are redundant, except for arrays. They are also a nuisance to work with. Recent commit "qapi: Start to elide redundant has_FOO in generated C" provided the means to elide them step by step. This is the step for qapi/block*.json. Said commit explains the transformation in more detail. There is one instance of the invariant violation mentioned there: qcow2_signal_corruption() passes false, "" when node_name is an empty string. Take care to pass NULL then. The previous two commits cleaned up two more. Additionally, helper bdrv_latency_histogram_stats() loses its output parameters and returns a value instead. Cc: Kevin Wolf <kwolf@redhat.com> Cc: Hanna Reitz <hreitz@redhat.com> Cc: qemu-block@nongnu.org Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20221104160712.3005652-11-armbru@redhat.com> [Fixes for #ifndef LIBRBD_SUPPORTS_ENCRYPTION and MacOS squashed in]
2022-10-30Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into stagingStefan Hajnoczi
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>
2022-10-27qcow: switch to *_co_* functionsAlberto Faria
Signed-off-by: Alberto Faria <afaria@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20221013123711.620631-19-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-27qcow: manually add more coroutine_fn annotationsPaolo Bonzini
get_cluster_offset() and decompress_cluster() are only called from the read and write paths. The validity of these was double-checked with Alberto Faria's static analyzer. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20221013123711.620631-12-pbonzini@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-27block: introduce bdrv_open_file_child() helperVladimir Sementsov-Ogievskiy
Almost all drivers call bdrv_open_child() similarly. Let's create a helper for this. The only not updated drivers that call bdrv_open_child() to set bs->file are raw-format and snapshot-access: raw-format sometimes want to have filtered child but don't set drv->is_filter to true. snapshot-access wants only DATA | PRIMARY Possibly we should implement drv->is_filter_func() handler, to consider raw-format as filter when it works as filter.. But it's another story. Note also, that we decrease assignments to bs->file in code: it helps us restrict modifying this field in further commit. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220726201134.924743-3-vsementsov@yandex-team.ru> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2022-10-26block: add BDRV_REQ_REGISTERED_BUF request flagStefan Hajnoczi
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>
2022-07-12block: Change blk_{pread,pwrite}() param orderAlberto Faria
Swap 'buf' and 'bytes' around for consistency with blk_co_{pread,pwrite}(), and in preparation to implement these functions using generated_co_wrapper. Callers were updated using this Coccinelle script: @@ expression blk, offset, buf, bytes, flags; @@ - blk_pread(blk, offset, buf, bytes, flags) + blk_pread(blk, offset, bytes, buf, flags) @@ expression blk, offset, buf, bytes, flags; @@ - blk_pwrite(blk, offset, buf, bytes, flags) + blk_pwrite(blk, offset, bytes, buf, flags) It had no effect on hw/block/nand.c, presumably due to the #if, so that file was updated manually. Overly-long lines were then fixed by hand. Signed-off-by: Alberto Faria <afaria@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Hanna Reitz <hreitz@redhat.com> Message-Id: <20220705161527.1054072-4-afaria@redhat.com> Signed-off-by: Hanna Reitz <hreitz@redhat.com>
2022-07-12block: Make blk_{pread,pwrite}() return 0 on successAlberto Faria
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. Signed-off-by: Alberto Faria <afaria@redhat.com> Message-Id: <20220705161527.1054072-2-afaria@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 Faria
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 Faria
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 Faria
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>
2022-03-07osdep: Move memalign-related functions to their own headerPeter Maydell
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
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>
2020-09-15block/qcow: remove runtime optsJohn Snow
Introduced by d85f4222b468, These were seemingly never used at all. Signed-off-by: John Snow <jsnow@redhat.com> Message-Id: <20200806211345.2925343-3-jsnow@redhat.com> Signed-off-by: Max Reitz <mreitz@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>
2020-07-10error: 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>
2020-07-10error: 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>
2020-05-18block: Use bdrv_default_perms()Max Reitz
bdrv_default_perms() can decide which permission profile to use based on the BdrvChildRole, so block drivers do not need to select it explicitly. The blkverify driver now no longer shares the WRITE permission for the image to verify. We thus have to adjust two places in test-block-iothread not to take it. (Note that in theory, blkverify should behave like quorum in this regard and share neither WRITE nor RESIZE for both of its children. In practice, it does not really matter, because blkverify is used only for debugging, so we might as well keep its permissions rather liberal.) Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200513110544.176672-30-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-05-18block: Make format drivers use child_of_bdsMax Reitz
Commonly, they need to pass the BDRV_CHILD_IMAGE set as the BdrvChildRole; but there are exceptions for drivers with external data files (qcow2 and vmdk). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200513110544.176672-26-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-05-18block: Add BdrvChildRole to BdrvChildMax Reitz
For now, it is always set to 0. Later patches in this series will ensure that all callers pass an appropriate combination of flags. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20200513110544.176672-6-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-05-18block: Add BlockDriver.is_formatMax Reitz
We want to unify child_format and child_file at some point. One of the important things that set format drivers apart from other drivers is that they do not expect other format nodes under them (except in the backing chain), i.e. we must not probe formats inside of formats. That means we need something on which to distinguish format drivers from others, and hence this flag. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-Id: <20200513110544.176672-3-mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-05-05block: Add blk_new_with_bs() helperEric Blake
There are several callers that need to create a new block backend from an existing BDS; make the task slightly easier with a common helper routine. Suggested-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <20200424190903.522087-2-eblake@redhat.com> [mreitz: Set @ret only in error paths, see https://lists.nongnu.org/archive/html/qemu-block/2020-04/msg01216.html] Signed-off-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200428192648.749066-2-eblake@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-04-30block: Add flags to bdrv(_co)_truncate()Kevin Wolf
Now that block drivers can support flags for .bdrv_co_truncate, expose the parameter in the node level interfaces bdrv_co_truncate() and bdrv_truncate(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Reviewed-by: Max Reitz <mreitz@redhat.com> Message-Id: <20200424125448.63318-3-kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2020-03-26block: pass BlockDriver reference to the .bdrv_co_createMaxim Levitsky
This will allow the reuse of a single generic .bdrv_co_create implementation for several drivers. No functional changes. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200326011218.29230-2-mlevitsk@redhat.com> Reviewed-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-28block: Add @exact parameter to bdrv_co_truncate()Max Reitz
We have two drivers (iscsi and file-posix) that (in some cases) return success from their .bdrv_co_truncate() implementation if the block device is larger than the requested offset, but cannot be shrunk. Some callers do not want that behavior, so this patch adds a new parameter that they can use to turn off that behavior. This patch just adds the parameter and lets the block/io.c and block/block-backend.c functions pass it around. All other callers always pass false and none of the implementations evaluate it, so that this patch does not change existing behavior. Future patches take care of that. Suggested-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190918095144.955-5-mreitz@redhat.com Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-28block: Do not truncate file node when formattingMax Reitz
There is no reason why the format drivers need to truncate the protocol node when formatting it. When using the old .bdrv_co_create_ops() interface, the file will be created with no size option anyway, which generally gives it a size of 0. (Exceptions are block devices, which cannot be truncated anyway.) When using blockdev-create, the user must have given the file node some size anyway, so there is no reason why we should override that. qed is an exception, it needs the file to start completely empty (as explained by c743849bee7333c7ef256b7e12e34ed6f907064f). Signed-off-by: Max Reitz <mreitz@redhat.com> Message-id: 20190918095144.955-4-mreitz@redhat.com Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-07-08block/qcow: Improve error when opening qcow2 files as qcowJohn Snow
Reported-by: radmehrsaeed7@gmail.com Fixes: https://bugs.launchpad.net/bugs/1832914 Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-06-04block: Add BlockBackend.ctxKevin Wolf
This adds a new parameter to blk_new() which requires its callers to declare from which AioContext this BlockBackend is going to be used (or the locks of which AioContext need to be taken anyway). The given context is only stored and kept up to date when changing AioContexts. Actually applying the stored AioContext to the root node is saved for another commit. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-04-30block/qcow: use buffer-based ioVladimir Sementsov-Ogievskiy
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2019-02-26Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell
Block layer patches: - Block graph change fixes (avoid loops, cope with non-tree graphs) - bdrv_set_aio_context() related fixes - HMP snapshot commands: Use only tag, not the ID to identify snapshots - qmeu-img, commit: Error path fixes - block/nvme: Build fix for gcc 9 - MAINTAINERS updates - Fix various issues with bdrv_refresh_filename() - Fix various iotests - Include LUKS overhead in qemu-img measure for qcow2 - A fix for vmdk's image creation interface # gpg: Signature made Mon 25 Feb 2019 14:18:15 GMT # gpg: using RSA key 7F09B272C88F2FD6 # 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: (71 commits) iotests: Skip 211 on insufficient memory vmdk: false positive of compat6 with hwversion not set iotests: add LUKS payload overhead to 178 qemu-img measure test qcow2: include LUKS payload overhead in qemu-img measure iotests.py: s/_/-/g on keys in qmp_log() iotests: Let 045 be run concurrently iotests: Filter SSH paths iotests.py: Filter filename in any string value iotests.py: Add is_str() iotests: Fix 207 to use QMP filters for qmp_log iotests: Fix 232 for LUKS iotests: Remove superfluous rm from 232 iotests: Fix 237 for Python 2.x iotests: Re-add filename filters iotests: Test json:{} filenames of internal BDSs block: BDS options may lack the "driver" option block/null: Generate filename even with latency-ns block/curl: Implement bdrv_refresh_filename() block/curl: Harmonize option defaults block/nvme: Fix bdrv_refresh_filename() ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
2019-02-25block: Add BDS.auto_backing_fileMax Reitz
If the backing file is overridden, this most probably does change the guest-visible data of a BDS. Therefore, we will need to consider this in bdrv_refresh_filename(). To see whether it has been overridden, we might want to compare bs->backing_file and bs->backing->bs->filename. However, bs->backing_file is changed by bdrv_set_backing_hd() (which is just used to change the backing child at runtime, without modifying the image header), so bs->backing_file most of the time simply contains a copy of bs->backing->bs->filename anyway, so it is useless for such a comparison. This patch adds an auto_backing_file BDS field which contains the backing file path as indicated by the image header, which is not changed by bdrv_set_backing_hd(). Because of bdrv_refresh_filename() magic, however, a BDS's filename may differ from what has been specified during bdrv_open(). Then, the comparison between bs->auto_backing_file and bs->backing->bs->filename may fail even though bs->backing was opened from bs->auto_backing_file. To mitigate this, we can copy the real BDS's filename (after the whole bdrv_open() and bdrv_refresh_filename() process) into bs->auto_backing_file, if we know the former has been opened based on the latter. This is only possible if no options modifying the backing file's behavior have been specified, though. To simplify things, this patch only copies the filename from the backing file if no options have been specified for it at all. Furthermore, there are cases where an overlay is created by qemu which already contains a BDS's filename (e.g. in blockdev-snapshot-sync). We do not need to worry about updating the overlay's bs->auto_backing_file there, because we actually wrote a post-bdrv_refresh_filename() filename into the image header. So all in all, there will be false negatives where (as of a future patch) bdrv_refresh_filename() will assume that the backing file differs from what was specified in the image header, even though it really does not. However, these cases should be limited to where (1) the user actually did override something in the backing chain (e.g. by specifying options for the backing file), or (2) the user executed a QMP command to change some node's backing file (e.g. change-backing-file or block-commit with @backing-file given) where the given filename does not happen to coincide with qemu's idea of the backing BDS's filename. Then again, (1) really is limited to -drive. With -blockdev or blockdev-add, you have to adhere to the schema, so a user cannot give partial "unimportant" options (e.g. by just setting backing.node-name and leaving the rest to the image header). Therefore, trying to fix this would mean trying to fix something for -drive only. To improve on (2), we would need a full infrastructure to "canonicalize" an arbitrary filename (+ options), so it can be compared against another. That seems a bit over the top, considering that filenames nowadays are there mostly for the user's entertainment. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Message-id: 20190201192935.18394-5-mreitz@redhat.com Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-02-22block/qcow: use qemu_iovec_init_bufVladimir Sementsov-Ogievskiy
Use new qemu_iovec_init_buf() instead of qemu_iovec_init_external( ... , 1), which simplifies the code. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20190218140926.333779-9-vsementsov@virtuozzo.com Message-Id: <20190218140926.333779-9-vsementsov@virtuozzo.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2018-12-12crypto: support multiple threads accessing one QCryptoBlockVladimir Sementsov-Ogievskiy
The two thing that should be handled are cipher and ivgen. For ivgen the solution is just mutex, as iv calculations should not be long in comparison with encryption/decryption. And for cipher let's just keep per-thread ciphers. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Reviewed-by: Alberto Garcia <berto@igalia.com> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-11-05block/qcow: Don't take address of fields in packed structsPeter Maydell
Taking the address of a field in a packed struct is a bad idea, because it might not be actually aligned enough for that pointer type (and thus cause a crash on dereference on some host architectures). Newer versions of clang warn about this. Avoid the bug by not using the "modify in place" byte swapping functions. There are a few places where the in-place swap function is used on something other than a packed struct field; we convert those anyway, for consistency. This patch was produced with the following spatch script: @@ expression E; @@ -be16_to_cpus(&E); +E = be16_to_cpu(E); @@ expression E; @@ -be32_to_cpus(&E); +E = be32_to_cpu(E); @@ expression E; @@ -be64_to_cpus(&E); +E = be64_to_cpu(E); @@ expression E; @@ -cpu_to_be16s(&E); +E = cpu_to_be16(E); @@ expression E; @@ -cpu_to_be32s(&E); +E = cpu_to_be32(E); @@ expression E; @@ -cpu_to_be64s(&E); +E = cpu_to_be64(E); Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Tested-by: John Snow <jsnow@redhat.com> Reviewed-by: John Snow <jsnow@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2018-07-30qcow: fix a reference leakKONRAD Frederic
Since 42a3e1ab367cdf38cce093de24eb406b99a4ef96 qemu asserts when using the vvfat driver: git clone git://qemu.org/qemu.git cd qemu ./configure --target-list=ppc-softmmu --enable-debug make -j8 mkdir foo touch foo/hello ./ppc-softmmu/qemu-system-ppc -M prep --nographic --monitor null \ -hda fat:rw:./foo "Ctrl-C" qemu-system-ppc: block.c:3368: bdrv_close_all: Assertion \ `((&all_bdrv_states)->tqh_first == ((void *)0))' failed. This is because we reference bs twice in qcow_co_create(..) one time in bdrv_open_blockdev_ref(..) and in blk_insert_bs(..) but we unref it only once in blk_unref which leads to the reference leak. Note that I didn't tested much QCOW after this change as I don't use it much. Signed-off-by: KONRAD Frederic <frederic.konrad@adacore.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>