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2025-12-04block: enable per-cpu bio cache by defaultFengnan Chang
Since after commit 12e4e8c7ab59 ("io_uring/rw: enable bio caches for IRQ rw"), bio_put is safe for task and irq context, bio_alloc_bioset is safe for task context and no one calls in irq context, so we can enable per cpu bio cache by default. Benchmarked with t/io_uring and ext4+nvme: taskset -c 6 /root/fio/t/io_uring -p0 -d128 -b4096 -s1 -c1 -F1 -B1 -R1 -X1 -n1 -P1 /mnt/testfile base IOPS is 562K, patch IOPS is 574K. The CPU usage of bio_alloc_bioset decrease from 1.42% to 1.22%. The worst case is allocate bio in CPU A but free in CPU B, still use t/io_uring and ext4+nvme: base IOPS is 648K, patch IOPS is 647K. Also use fio test ext4/xfs with libaio/sync/io_uring on null_blk and nvme, no obvious performance regression. Signed-off-by: Fengnan Chang <changfengnan@bytedance.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-12-03Merge tag 'for-6.19/io_uring-20251201' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring updates from Jens Axboe: - Unify how task_work cancelations are detected, placing it in the task_work running state rather than needing to check the task state - Series cleaning up and moving the cancelation code to where it belongs, in cancel.c - Cleanup of waitid and futex argument handling - Add support for mixed sized SQEs. 6.18 added support for mixed sized CQEs, improving flexibility and efficiency of workloads that need big CQEs. This adds similar support for SQEs, where the occasional need for a 128b SQE doesn't necessitate having all SQEs be 128b in size - Introduce zcrx and SQ/CQ layout queries. The former returns what zcrx features are available. And both return the ring size information to help with allocation size calculation for user provided rings like IORING_SETUP_NO_MMAP and IORING_MEM_REGION_TYPE_USER - Zcrx updates for 6.19. It includes a bunch of small patches, IORING_REGISTER_ZCRX_CTRL and RQ flushing and David's work on sharing zcrx b/w multiple io_uring instances - Series cleaning up ring initializations, notable deduplicating ring size and offset calculations. It also moves most of the checking before doing any allocations, making the code simpler - Add support for getsockname and getpeername, which is mostly a trivial hookup after a bit of refactoring on the networking side - Various fixes and cleanups * tag 'for-6.19/io_uring-20251201' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (68 commits) io_uring: Introduce getsockname io_uring cmd socket: Split out a getsockname helper for io_uring socket: Unify getsockname and getpeername implementation io_uring/query: drop unused io_handle_query_entry() ctx arg io_uring/kbuf: remove obsolete buf_nr_pages and update comments io_uring/register: use correct location for io_rings_layout io_uring/zcrx: share an ifq between rings io_uring/zcrx: add io_fill_zcrx_offsets() io_uring/zcrx: export zcrx via a file io_uring/zcrx: move io_zcrx_scrub() and dependencies up io_uring/zcrx: count zcrx users io_uring/zcrx: add sync refill queue flushing io_uring/zcrx: introduce IORING_REGISTER_ZCRX_CTRL io_uring/zcrx: elide passing msg flags io_uring/zcrx: use folio_nr_pages() instead of shift operation io_uring/zcrx: convert to use netmem_desc io_uring/query: introduce rings info query io_uring/query: introduce zcrx query io_uring: move cq/sq user offset init around io_uring: pre-calculate scq layout ...
2025-12-01Merge tag 'vfs-6.19-rc1.iomap' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull iomap updates from Christian Brauner: "FUSE iomap Support for Buffered Reads: This adds iomap support for FUSE buffered reads and readahead. This enables granular uptodate tracking with large folios so only non-uptodate portions need to be read. Also fixes a race condition with large folios + writeback cache that could cause data corruption on partial writes followed by reads. - Refactored iomap read/readahead bio logic into helpers - Added caller-provided callbacks for read operations - Moved buffered IO bio logic into new file - FUSE now uses iomap for read_folio and readahead Zero Range Folio Batch Support: Add folio batch support for iomap_zero_range() to handle dirty folios over unwritten mappings. Fix raciness issues where dirty data could be lost during zero range operations. - filemap_get_folios_tag_range() helper for dirty folio lookup - Optional zero range dirty folio processing - XFS fills dirty folios on zero range of unwritten mappings - Removed old partial EOF zeroing optimization DIO Write Completions from Interrupt Context: Restore pre-iomap behavior where pure overwrite completions run inline rather than being deferred to workqueue. Reduces context switches for high-performance workloads like ScyllaDB. - Removed unused IOCB_DIO_CALLER_COMP code - Error completions always run in user context (fixes zonefs) - Reworked REQ_FUA selection logic - Inverted IOMAP_DIO_INLINE_COMP to IOMAP_DIO_OFFLOAD_COMP Buffered IO Cleanups: Some performance and code clarity improvements: - Replace manual bitmap scanning with find_next_bit() - Simplify read skip logic for writes - Optimize pending async writeback accounting - Better variable naming - Documentation for iomap_finish_folio_write() requirements Misaligned Vectors for Zoned XFS: Enables sub-block aligned vectors in XFS always-COW mode for zoned devices via new IOMAP_DIO_FSBLOCK_ALIGNED flag. Bug Fixes: - Allocate s_dio_done_wq for async reads (fixes syzbot report after error completion changes) - Fix iomap_read_end() for already uptodate folios (regression fix)" * tag 'vfs-6.19-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (40 commits) iomap: allocate s_dio_done_wq for async reads as well iomap: fix iomap_read_end() for already uptodate folios iomap: invert the polarity of IOMAP_DIO_INLINE_COMP iomap: support write completions from interrupt context iomap: rework REQ_FUA selection iomap: always run error completions in user context fs, iomap: remove IOCB_DIO_CALLER_COMP iomap: use find_next_bit() for uptodate bitmap scanning iomap: use find_next_bit() for dirty bitmap scanning iomap: simplify when reads can be skipped for writes iomap: simplify ->read_folio_range() error handling for reads iomap: optimize pending async writeback accounting docs: document iomap writeback's iomap_finish_folio_write() requirement iomap: account for unaligned end offsets when truncating read range iomap: rename bytes_pending/bytes_accounted to bytes_submitted/bytes_not_submitted xfs: support sub-block aligned vectors in always COW mode iomap: add IOMAP_DIO_FSBLOCK_ALIGNED flag xfs: error tag to force zeroing on debug kernels iomap: remove old partial eof zeroing optimization xfs: fill dirty folios on zero range of unwritten mappings ...
2025-11-25fs, iomap: remove IOCB_DIO_CALLER_COMPChristoph Hellwig
This was added by commit 099ada2c8726 ("io_uring/rw: add write support for IOCB_DIO_CALLER_COMP") and disabled a little later by commit 838b35bb6a89 ("io_uring/rw: disable IOCB_DIO_CALLER_COMP") because it didn't work. Remove all the related code that sat unused for 2 years. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20251113170633.1453259-2-hch@lst.de Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-13Merge branch 'io_uring-6.18' into for-6.19/io_uringJens Axboe
Merge 6.18-rc io_uring fixes, as certain coming changes depend on some of these. * io_uring-6.18: io_uring/rsrc: don't use blk_rq_nr_phys_segments() as number of bvecs io_uring/query: return number of available queries io_uring/rw: ensure allocated iovec gets cleared for early failure io_uring: fix regbuf vector size truncation io_uring: fix types for region size calulation io_uring/zcrx: remove sync refill uapi io_uring: fix buffer auto-commit for multishot uring_cmd io_uring: correct __must_hold annotation in io_install_fixed_file io_uring zcrx: add MAINTAINERS entry io_uring: Fix code indentation error io_uring/sqpoll: be smarter on when to update the stime usage io_uring/sqpoll: switch away from getrusage() for CPU accounting io_uring: fix incorrect unlikely() usage in io_waitid_prep() Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-10io_uring/rw: ensure allocated iovec gets cleared for early failureJens Axboe
A previous commit reused the recyling infrastructure for early cleanup, but this is not enough for the case where our internal caches have overflowed. If this happens, then the allocated iovec can get leaked if the request is also aborted early. Reinstate the previous forced free of the iovec for that situation. Cc: stable@vger.kernel.org Reported-by: syzbot+3c93637d7648c24e1fd0@syzkaller.appspotmail.com Tested-by: syzbot+3c93637d7648c24e1fd0@syzkaller.appspotmail.com Fixes: 9ac273ae3dc2 ("io_uring/rw: use io_rw_recycle() from cleanup path") Link: https://lore.kernel.org/io-uring/69122a59.a70a0220.22f260.00fd.GAE@google.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-05io_uring: fix typos and comment wordingAlok Tiwari
Corrected spelling mistakes in comments "reuqests" -> "requests", "noifications" -> "notifications", "seperately" -> "separately"). Fixed a small grammar issue ("then" -> "than"). Updated "flag" -> "flags" in fdinfo.c Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-11-03io_uring: add wrapper type for io_req_tw_func_t argCaleb Sander Mateos
In preparation for uring_cmd implementations to implement functions with the io_req_tw_func_t signature, introduce a wrapper struct io_tw_req to hide the struct io_kiocb * argument. The intention is for only the io_uring core to access the inner struct io_kiocb *. uring_cmd implementations should instead call a helper from io_uring/cmd.h to convert struct io_tw_req to struct io_uring_cmd *. Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-15io_uring/rw: check for NULL io_br_sel when putting a bufferJens Axboe
Both the read and write side use kiocb_done() to finish a request, and kiocb_done() will call io_put_kbuf() in case a provided buffer was used for the request. Provided buffers are not supported for writes, hence NULL is being passed in. This normally works fine, as io_put_kbuf() won't actually use the value unless REQ_F_BUFFER_RING or REQ_F_BUFFER_SELECTED is set in the request flags. But depending on compiler (or whether or not CONFIG_CC_OPTIMIZE_FOR_SIZE is set), that may be done even though the value is never used. This will then cause a NULL pointer dereference. Make it a bit more obvious and check for a NULL io_br_sel, and don't even bother calling io_put_kbuf() for that case. Fixes: 5fda51255439 ("io_uring/kbuf: switch to storing struct io_buffer_list locally") Reported-by: David Howells <dhowells@redhat.com> Tested-by: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-13Revert "io_uring/rw: drop -EOPNOTSUPP check in __io_complete_rw_common()"Jens Axboe
This reverts commit 90bfb28d5fa8127a113a140c9791ea0b40ab156a. Kevin reports that this commit causes an issue for him with LVM snapshots, most likely because of turning off NOWAIT support while a snapshot is being created. This makes -EOPNOTSUPP bubble back through the completion handler, where io_uring read/write handling should just retry it. Reinstate the previous check removed by the referenced commit. Cc: stable@vger.kernel.org Fixes: 90bfb28d5fa8 ("io_uring/rw: drop -EOPNOTSUPP check in __io_complete_rw_common()") Reported-by: Salvatore Bonaccorso <carnil@debian.org> Reported-by: Kevin Lumik <kevin@xf.ee> Link: https://lore.kernel.org/io-uring/cceb723c-051b-4de2-9a4c-4aa82e1619ee@kernel.dk/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-10-02Merge tag 'for-6.18/io_uring-20250929' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull io_uring updates from Jens Axboe: - Store ring provided buffers locally for the users, rather than stuff them into struct io_kiocb. These types of buffers must always be fully consumed or recycled in the current context, and leaving them in struct io_kiocb is hence not a good ideas as that struct has a vastly different life time. Basically just an architecture cleanup that can help prevent issues with ring provided buffers in the future. - Support for mixed CQE sizes in the same ring. Before this change, a CQ ring either used the default 16b CQEs, or it was setup with 32b CQE using IORING_SETUP_CQE32. For use cases where a few 32b CQEs were needed, this caused everything else to use big CQEs. This is wasteful both in terms of memory usage, but also memory bandwidth for the posted CQEs. With IORING_SETUP_CQE_MIXED, applications may use request types that post both normal 16b and big 32b CQEs on the same ring. - Add helpers for async data management, to make it harder for opcode handlers to mess it up. - Add support for multishot for uring_cmd, which ublk can use. This helps improve efficiency, by providing a persistent request type that can trigger multiple CQEs. - Add initial support for ring feature querying. We had basic support for probe operations, but the API isn't great. Rather than expand that, add support for QUERY which is easily expandable and can cover a lot more cases than the existing probe support. This will help applications get a better idea of what operations are supported on a given host. - zcrx improvements from Pavel: - Improve refill entry alignment for better caching - Various cleanups, especially around deduplicating normal memory vs dmabuf setup. - Generalisation of the niov size (Patch 12). It's still hard coded to PAGE_SIZE on init, but will let the user to specify the rx buffer length on setup. - Syscall / synchronous bufer return. It'll be used as a slow fallback path for returning buffers when the refill queue is full. Useful for tolerating slight queue size misconfiguration or with inconsistent load. - Accounting more memory to cgroups. - Additional independent cleanups that will also be useful for mutli-area support. - Various fixes and cleanups * tag 'for-6.18/io_uring-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (68 commits) io_uring/cmd: drop unused res2 param from io_uring_cmd_done() io_uring: fix nvme's 32b cqes on mixed cq io_uring/query: cap number of queries io_uring/query: prevent infinite loops io_uring/zcrx: account niov arrays to cgroup io_uring/zcrx: allow synchronous buffer return io_uring/zcrx: introduce io_parse_rqe() io_uring/zcrx: don't adjust free cache space io_uring/zcrx: use guards for the refill lock io_uring/zcrx: reduce netmem scope in refill io_uring/zcrx: protect netdev with pp_lock io_uring/zcrx: rename dma lock io_uring/zcrx: make niov size variable io_uring/zcrx: set sgt for umem area io_uring/zcrx: remove dmabuf_offset io_uring/zcrx: deduplicate area mapping io_uring/zcrx: pass ifq to io_zcrx_alloc_fallback() io_uring/zcrx: check all niovs filled with dma addresses io_uring/zcrx: move area reg checks into io_import_area io_uring/zcrx: don't pass slot to io_zcrx_create_area ...
2025-09-08io_uring: don't include filetable.h in io_uring.hCaleb Sander Mateos
io_uring/io_uring.h doesn't use anything declared in io_uring/filetable.h, so drop the unnecessary #include. Add filetable.h includes in .c files previously relying on the transitive include from io_uring.h. Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-27io_uring: add async data clear/free helpersJens Axboe
Futex recently had an issue where it mishandled how ->async_data and REQ_F_ASYNC_DATA is handled. To avoid future issues like that, add a set of helpers that either clear or clear-and-free the async data assigned to a struct io_kiocb. Convert existing manual handling of that to use the helpers. No intended functional changes in this patch. Reviewed-by: Caleb Sander Mateos <csander@purestorage.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-24io_uring/kbuf: switch to storing struct io_buffer_list locallyJens Axboe
Currently the buffer list is stored in struct io_kiocb. The buffer list can be of two types: 1) Classic/legacy buffer list. These don't need to get referenced after a buffer pick, and hence storing them in struct io_kiocb is perfectly fine. 2) Ring provided buffer lists. These DO need to be referenced after the initial buffer pick, as they need to get consumed later on. This can be either just incrementing the head of the ring, or it can be consuming parts of a buffer if incremental buffer consumptions has been configured. For case 2, io_uring needs to be careful not to access the buffer list after the initial pick-and-execute context. The core does recycling of these, but it's easy to make a mistake, because it's stored in the io_kiocb which does persist across multiple execution contexts. Either because it's a multishot request, or simply because it needed some kind of async trigger (eg poll) for retry purposes. Add a struct io_buffer_list to struct io_br_sel, which is always on stack for the various users of it. This prevents the buffer list from leaking outside of that execution context, and additionally it enables kbuf to not even pass back the struct io_buffer_list if the given context isn't appropriately locked already. This doesn't fix any bugs, it's simply a defensive measure to prevent any issues with reuse of a buffer list. Link: https://lore.kernel.org/r/20250821020750.598432-12-axboe@kernel.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-24io_uring/rw: recycle buffers manually for non-mshot readsJens Axboe
The mshot side of reads already does this, but the regular read path does not. This leads to needing recycling checks sprinkled in various spots in the "go async" path, like arming poll. In preparation for getting rid of those, ensure that read recycles appropriately. Link: https://lore.kernel.org/r/20250821020750.598432-8-axboe@kernel.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-24io_uring/kbuf: introduce struct io_br_selJens Axboe
Rather than return addresses directly from buffer selection, add a struct around it. No functional changes in this patch, it's in preparation for storing more buffer related information locally, rather than in struct io_kiocb. Link: https://lore.kernel.org/r/20250821020750.598432-7-axboe@kernel.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-24io_uring/kbuf: pass in struct io_buffer_list to commit/recycle helpersJens Axboe
Rather than have this implied being in the io_kiocb, pass it in directly so it's immediately obvious where these users of ->buf_list are coming from. Link: https://lore.kernel.org/r/20250821020750.598432-6-axboe@kernel.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-24io_uring/kbuf: drop 'issue_flags' from io_put_kbuf(s)() argumentsJens Axboe
Picking multiple buffers always requires the ring lock to be held across the operation, so there's no need to pass in the issue_flags to io_put_kbufs(). On the single buffer side, if the initial picking of a ring buffer was unlocked, then it will have been committed already. For legacy buffers, no locking is required, as they will simply be freed. Link: https://lore.kernel.org/r/20250821020750.598432-3-axboe@kernel.dk Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-08-20fs: add a FMODE_ flag to indicate IOCB_HAS_METADATA availabilityChristoph Hellwig
Currently the kernel will happily route io_uring requests with metadata to file operations that don't support it. Add a FMODE_ flag to guard that. Fixes: 4de2ce04c862 ("fs: introduce IOCB_HAS_METADATA for metadata") Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250819082517.2038819-2-hch@lst.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-07io_uring/rw: cast rw->flags assignment to rwf_tJens Axboe
kernel test robot reports that a recent change of the sqe->rw_flags field throws a sparse warning on 32-bit archs: >> io_uring/rw.c:291:19: sparse: sparse: incorrect type in assignment (different base types) @@ expected restricted __kernel_rwf_t [usertype] flags @@ got unsigned int @@ io_uring/rw.c:291:19: sparse: expected restricted __kernel_rwf_t [usertype] flags io_uring/rw.c:291:19: sparse: got unsigned int Force cast it to rwf_t to silence that new sparse warning. Fixes: cf73d9970ea4 ("io_uring: don't use int for ABI") Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202507032211.PwSNPNSP-lkp@intel.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-26Merge tag 'for-6.16/io_uring-20250523' of git://git.kernel.dk/linuxLinus Torvalds
Pull io_uring updates from Jens Axboe: - Avoid indirect function calls in io-wq for executing and freeing work. The design of io-wq is such that it can be a generic mechanism, but as it's just used by io_uring now, may as well avoid these indirect calls - Clean up registered buffers for networking - Add support for IORING_OP_PIPE. Pretty straight forward, allows creating pipes with io_uring, particularly useful for having these be instantiated as direct descriptors - Clean up the coalescing support fore registered buffers - Add support for multiple interface queues for zero-copy rx networking. As this feature was merged for 6.15 it supported just a single ifq per ring - Clean up the eventfd support - Add dma-buf support to zero-copy rx - Clean up and improving the request draining support - Clean up provided buffer support, most notably with an eye toward making the legacy support less intrusive - Minor fdinfo cleanups, dropping support for dumping what credentials are registered - Improve support for overflow CQE handling, getting rid of GFP_ATOMIC for allocating overflow entries where possible - Improve detection of cases where io-wq doesn't need to spawn a new worker unnecessarily - Various little cleanups * tag 'for-6.16/io_uring-20250523' of git://git.kernel.dk/linux: (59 commits) io_uring/cmd: warn on reg buf imports by ineligible cmds io_uring/io-wq: only create a new worker if it can make progress io_uring/io-wq: ignore non-busy worker going to sleep io_uring/io-wq: move hash helpers to the top trace/io_uring: fix io_uring_local_work_run ctx documentation io_uring: finish IOU_OK -> IOU_COMPLETE transition io_uring: add new helpers for posting overflows io_uring: pass in struct io_big_cqe to io_alloc_ocqe() io_uring: make io_alloc_ocqe() take a struct io_cqe pointer io_uring: split alloc and add of overflow io_uring: open code io_req_cqe_overflow() io_uring/fdinfo: get rid of dumping credentials io_uring/fdinfo: only compile if CONFIG_PROC_FS is set io_uring/kbuf: unify legacy buf provision and removal io_uring/kbuf: refactor __io_remove_buffers io_uring/kbuf: don't compute size twice on prep io_uring/kbuf: drop extra vars in io_register_pbuf_ring io_uring/kbuf: use mem_is_zero() io_uring/kbuf: account ring io_buffer_list memory io_uring: drain based on allocates reqs ...
2025-05-21io_uring: finish IOU_OK -> IOU_COMPLETE transitionJens Axboe
IOU_COMPLETE is more descriptive, in that it explicitly says that the return value means "please post a completion for this request". This patch completes the transition from IOU_OK to IOU_COMPLETE, replacing existing IOU_OK users. This is a purely mechanical change. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-05-06io_uring: enable per-io write streamsKeith Busch
Allow userspace to pass a per-I/O write stream in the SQE: __u8 write_stream; The __u8 type matches the size the filesystems and block layer support. Application can query the supported values from the block devices max_write_streams sysfs attribute. Unsupported values are ignored by file operations that do not support write streams or rejected with an error by those that support them. Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Kanchan Joshi <joshi.k@samsung.com> Link: https://lore.kernel.org/r/20250506121732.8211-7-joshi.k@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-04-21io_uring/kbuf: pass bgid to io_buffer_select()Pavel Begunkov
The current situation with buffer group id juggling is not ideal. req->buf_index first stores the bgid, then it's overwritten by a buffer id, and then it can get restored back no recycling / etc. It's not so easy to control, and it's not handled consistently across request types with receive requests saving and restoring the bgid it by hand. It's a prep patch that adds a buffer group id argument to io_buffer_select(). The caller will be responsible for stashing a copy somewhere and passing it into the function. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/a210d6427cc3f4f42271a6853274cd5a50e56820.1743437358.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-28Merge tag 'for-6.15/io_uring-reg-vec-20250327' of git://git.kernel.dk/linuxLinus Torvalds
Pull more io_uring updates from Jens Axboe: "Final separate updates for io_uring. This started out as a series of cleanups improvements and improvements for registered buffers, but as the last series of the io_uring changes for 6.15, it also collected a few fixes for the other branches on top: - Add support for vectored fixed/registered buffers. Previously only single segments have been supported for commands, now vectored variants are supported as well. This series includes networking and file read/write support. - Small series unifying return codes across multi and single shot. - Small series cleaning up registerd buffer importing. - Adding support for vectored registered buffers for uring_cmd. - Fix for io-wq handling of command reissue. - Various little fixes and tweaks" * tag 'for-6.15/io_uring-reg-vec-20250327' of git://git.kernel.dk/linux: (25 commits) io_uring/net: fix io_req_post_cqe abuse by send bundle io_uring/net: use REQ_F_IMPORT_BUFFER for send_zc io_uring: move min_events sanitisation io_uring: rename "min" arg in io_iopoll_check() io_uring: open code __io_post_aux_cqe() io_uring: defer iowq cqe overflow via task_work io_uring: fix retry handling off iowq io_uring/net: only import send_zc buffer once io_uring/cmd: introduce io_uring_cmd_import_fixed_vec io_uring/cmd: add iovec cache for commands io_uring/cmd: don't expose entire cmd async data io_uring: rename the data cmd cache io_uring: rely on io_prep_reg_vec for iovec placement io_uring: introduce io_prep_reg_iovec() io_uring: unify STOP_MULTISHOT with IOU_OK io_uring: return -EAGAIN to continue multishot io_uring: cap cached iovec/bvec size io_uring/net: implement vectored reg bufs for zctx io_uring/net: convert to struct iou_vec io_uring/net: pull vec alloc out of msghdr import ...
2025-03-26Merge tag 'for-6.15/io_uring-20250322' of git://git.kernel.dk/linuxLinus Torvalds
Pull io_uring updates from Jens Axboe: "This is the first of the io_uring pull requests for the 6.15 merge window, there will be others once the net tree has gone in. This contains: - Cleanup and unification of cancelation handling across various request types. - Improvement for bundles, supporting them both for incrementally consumed buffers, and for non-multishot requests. - Enable toggling of using iowait while waiting on io_uring events or not. Unfortunately this is still tied with CPU frequency boosting on short waits, as the scheduler side has not been very receptive to splitting the (useless) iowait stat from the cpufreq implied boost. - Add support for kbuf nodes, enabling zero-copy support for the ublk block driver. - Various cleanups for resource node handling. - Series greatly cleaning up the legacy provided (non-ring based) buffers. For years, we've been pushing the ring provided buffers as the way to go, and that is what people have been using. Reduce the complexity and code associated with legacy provided buffers. - Series cleaning up the compat handling. - Series improving and cleaning up the recvmsg/sendmsg iovec and msg handling. - Series of cleanups for io-wq. - Start adding a bunch of selftests. The liburing repository generally carries feature and regression tests for everything, but at least for ublk initially, we'll try and go the route of having it in selftests as well. We'll see how this goes, might decide to migrate more tests this way in the future. - Various little cleanups and fixes" * tag 'for-6.15/io_uring-20250322' of git://git.kernel.dk/linux: (108 commits) selftests: ublk: add stripe target selftests: ublk: simplify loop io completion selftests: ublk: enable zero copy for null target selftests: ublk: prepare for supporting stripe target selftests: ublk: move common code into common.c selftests: ublk: increase max buffer size to 1MB selftests: ublk: add single sqe allocator helper selftests: ublk: add generic_01 for verifying sequential IO order selftests: ublk: fix starting ublk device io_uring: enable toggle of iowait usage when waiting on CQEs selftests: ublk: fix write cache implementation selftests: ublk: add variable for user to not show test result selftests: ublk: don't show `modprobe` failure selftests: ublk: add one dependency header io_uring/kbuf: enable bundles for incrementally consumed buffers Revert "io_uring/rsrc: simplify the bvec iter count calculation" selftests: ublk: improve test usability selftests: ublk: add stress test for covering IO vs. killing ublk server selftests: ublk: add one stress test for covering IO vs. removing device selftests: ublk: load/unload ublk_drv when preparing & cleaning up tests ...
2025-03-10io_uring: rely on io_prep_reg_vec for iovec placementPavel Begunkov
All vectored reg buffer users should use io_import_reg_vec() for iovec imports, since iovec placement is the function's responsibility and callers shouldn't know much about it, drop the offset parameter from io_prep_reg_vec() and calculate it inside. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/08ed87ca4bbc06724373b6ce06f36b703fe60c4e.1741457480.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-10io_uring: introduce io_prep_reg_iovec()Pavel Begunkov
iovecs that are turned into registered buffers are imported in a special way with an offset, so that later we can do an in place translation. Add a helper function taking care of it. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/7de2ecb9ed5efc3c5cf320232236966da5ad4ccc.1741457480.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-10io_uring: unify STOP_MULTISHOT with IOU_OKPavel Begunkov
IOU_OK means that the request ownership is now handed back to core io_uring and it has to complete it using the result provided in req->cqe. Same is true for multishot and IOU_STOP_MULTISHOT. Rename it into IOU_COMPLETE to avoid confusion and use for both modes. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/e6a5b2edb0eb9558acb1c8f1db38ac45fee95491.1741453534.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-10io_uring: return -EAGAIN to continue multishotPavel Begunkov
Multishot errors can be mapped 1:1 to normal errors, but there are not identical. It leads to a peculiar situation where all multishot requests has to check in what context they're run and return different codes. Unify them starting with EAGAIN / IOU_ISSUE_SKIP_COMPLETE(EIOCBQUEUED) pair, which mean that core io_uring still owns the request and it should be retried. In case of multishot it's naturally just continues to poll, otherwise it might poll, use iowq or do any other kind of allowed blocking. Introduce IOU_RETRY aliased to -EAGAIN for that. Apart from obvious upsides, multishot can now also check for misuse of IOU_ISSUE_SKIP_COMPLETE. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/da117b79ce72ecc3ab488c744e29fae9ba54e23b.1741453534.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-07io_uring: cap cached iovec/bvec sizePavel Begunkov
Bvecs can be large, put an arbitrary limit on the max vector size it can cache. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/823055fa6628daa24bbc9cd77c2da87e9a1e1e32.1741362889.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-07io_uring/rw: defer reg buf vec importPavel Begunkov
Import registered buffers for vectored reads and writes later at issue time as we now do for other fixed ops. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/e8491c976e4ab83a4e3dc428e9fe7555e59583b8.1741362889.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-07io_uring/rw: implement vectored registered rwPavel Begunkov
Implement registered buffer vectored reads with new opcodes IORING_OP_WRITEV_FIXED and IORING_OP_READV_FIXED. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d7c89eb481e870f598edc91cc66ff4d1e4ae3788.1741362889.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-07io_uring: introduce struct iou_vecPavel Begunkov
I need a convenient way to pass around and work with iovec+size pair, put them into a structure and makes use of it in rw.c Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/d39fadafc9e9047b0a292e5be6db3cf2f48bb1f7.1741362889.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-03-05io_uring/rw: ensure reissue path is correctly handled for IOPOLLJens Axboe
The IOPOLL path posts CQEs when the io_kiocb is marked as completed, so it cannot rely on the usual retry that non-IOPOLL requests do for read/write requests. If -EAGAIN is received and the request should be retried, go through the normal completion path and let the normal flush logic catch it and reissue it, like what is done for !IOPOLL reads or writes. Fixes: d803d123948f ("io_uring/rw: handle -EAGAIN retry at IO completion time") Reported-by: John Garry <john.g.garry@oracle.com> Link: https://lore.kernel.org/io-uring/2b43ccfa-644d-4a09-8f8f-39ad71810f41@oracle.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28io_uring: add support for kernel registered bvecsKeith Busch
Provide an interface for the kernel to leverage the existing pre-registered buffers that io_uring provides. User space can reference these later to achieve zero-copy IO. User space must register an empty fixed buffer table with io_uring in order for the kernel to make use of it. Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20250227223916.143006-5-kbusch@meta.com Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28io_uring/rw: move fixed buffer import to issue pathKeith Busch
Registered buffers may depend on a linked command, which makes the prep path too early to import. Move to the issue path when the node is actually needed like all the other users of fixed buffers. Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20250227223916.143006-3-kbusch@meta.com Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-28io_uring/rw: move buffer_select outside generic prepKeith Busch
Cleans up the generic rw prep to not require the do_import flag. Use a different prep function for callers that might need buffer select. Based-on-a-patch-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20250227223916.143006-2-kbusch@meta.com Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-27Merge branch 'io_uring-6.14' into for-6.15/io_uringJens Axboe
Merge mainline fixes into 6.15 branch, as upcoming patches depend on fixes that went into the 6.14 mainline branch. * io_uring-6.14: io_uring/net: save msg_control for compat io_uring/rw: clean up mshot forced sync mode io_uring/rw: move ki_complete init into prep io_uring/rw: don't directly use ki_complete io_uring/rw: forbid multishot async reads io_uring/rsrc: remove unused constants io_uring: fix spelling error in uapi io_uring.h io_uring: prevent opcode speculation io-wq: backoff when retrying worker creation
2025-02-27io_uring: combine buffer lookup and importPavel Begunkov
Registered buffer are currently imported in two steps, first we lookup a rsrc node and then use it to set up the iterator. The first part is usually done at the prep stage, and import happens whenever it's needed. As we want to defer binding to a node so that it works with linked requests, combine both steps into a single helper. Reviewed-by: Keith Busch <kbusch@kernel.org> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250224213116.3509093-6-kbusch@meta.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-27io_uring/rw: open code io_prep_rw_setup()Pavel Begunkov
Open code io_prep_rw_setup() into its only caller, it doesn't provide any meaningful abstraction anymore. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/61ba72e2d46119db71f27ab908018e6a6cd6c064.1740425922.git.asml.silence@gmail.com [axboe: fold in 'ret' being unused fix] Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-25io_uring/rw: extract helper for iovec importPavel Begunkov
Split out a helper out of __io_import_rw_buffer() that handles vectored buffers. I'll need it for registered vectored buffers, but it also looks cleaner, especially with parameters being properly named. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/075470cfb24be38709d946815f35ec846d966f41.1740425922.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-25io_uring/rw: rename io_import_iovec()Pavel Begunkov
io_import_iovec() is not limited to iovecs but also imports buffers for normal reads and selected buffers, rename it for clarity. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/91cea59340b61a8f52dc7b8e720274577a25188c.1740425922.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-25io_uring/rw: allocate async data in io_prep_rw()Pavel Begunkov
rw always allocates async_data, so instead of doing that deeper in prep calls inside of io_prep_rw_setup(), be a bit more explicit and do that early on in io_prep_rw(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/5ead621051bc3374d1e8d96f816454906a6afd71.1740425922.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-24io_uring/rw: shrink io_iov_compat_buffer_select_prepPavel Begunkov
Compat performance is not important and simplicity is more appreciated. Let's not be smart about it and use simpler copy_from_user() instead of access + __get_user pair. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/b334a3a5040efa424ded58e4d8a6ef2554324266.1740400452.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-24io_uring/rw: compile out compat param passingPavel Begunkov
Even when COMPAT is compiled out, we still have to pass ctx->compat to __import_iovec(). Replace the read with an indirection with a constant when the kernel doesn't support compat. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Anuj Gupta <anuj20.g@samsung.com> Link: https://lore.kernel.org/r/2819df9c8533c36b46d7baccbb317a0ec89da6cd.1740400452.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-19io_uring/rw: clean up mshot forced sync modePavel Begunkov
Move code forcing synchronous execution of multishot read requests out a more generic __io_read(). Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/4ad7b928c776d1ad59addb9fff64ef2d1fc474d5.1739919038.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-19io_uring/rw: move ki_complete init into prepPavel Begunkov
Initialise ki_complete during request prep stage, we'll depend on it not being reset during issue in the following patch. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/817624086bd5f0448b08c80623399919fda82f34.1739919038.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-19io_uring/rw: don't directly use ki_completePavel Begunkov
We want to avoid checking ->ki_complete directly in the io_uring completion path. Fortunately we have only two callback the selection of which depend on the ring constant flags, i.e. IOPOLL, so use that to infer the function. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/4eb4bdab8cbcf5bc87083f7047edc81e920ab83c.1739919038.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-19io_uring/rw: forbid multishot async readsPavel Begunkov
At the moment we can't sanely handle queuing an async request from a multishot context, so disable them. It shouldn't matter as pollable files / socekts don't normally do async. Patching it in __io_read() is not the cleanest way, but it's simpler than other options, so let's fix it there and clean up on top. Cc: stable@vger.kernel.org Reported-by: chase xd <sl1589472800@gmail.com> Fixes: fc68fcda04910 ("io_uring/rw: add support for IORING_OP_READ_MULTISHOT") Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://lore.kernel.org/r/7d51732c125159d17db4fe16f51ec41b936973f8.1739919038.git.asml.silence@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>