en Copyright 2025 Java http://opengrok.net:8080/history/linux/io_uring/loop.h#23acda7c221a76ff711d65f4ca90029d43b249a0 Merge tag 'for-7.1/io_uring-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxPull io_uring updates from Jens Axboe: - Add a callback driven main loop for io_uring, and BPF struct_ops on top to allow implementing custom event loop logic - Decouple IOPOLL from being a ring-wide all-or-nothing setting, allowing IOPOLL use cases to also issue certain white listed non-polled opcodes - Timeout improvements. Migrate internal timeout storage from timespec64 to ktime_t for simpler arithmetic and avoid copying of timespec data - Zero-copy receive (zcrx) updates: - Add a device-less mode (ZCRX_REG_NODEV) for testing and experimentation where data flows through the copy fallback path - Fix two-step unregistration regression, DMA length calculations, xarray mark usage, and a potential 32-bit overflow in id shifting - Refactoring toward multi-area support: dedicated refill queue struct, consolidated DMA syncing, netmem array refilling format, and guard-based locking - Zero-copy transmit (zctx) cleanup: - Unify io_send_zc() and io_sendmsg_zc() into a single function - Add vectorized registered buffer send for IORING_OP_SEND_ZC - Add separate notification user_data via sqe->addr3 so notification and completion CQEs can be distinguished without extra reference counting - Switch struct io_ring_ctx internal bitfields to explicit flag bits with atomic-safe accessors, and annotate the known harmless races on those flags - Various optimizations caching ctx and other request fields in local variables to avoid repeated loads, and cleanups for tctx setup, ring fd registration, and read path early returns* tag 'for-7.1/io_uring-20260411' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (58 commits) io_uring: unify getting ctx from passed in file descriptor io_uring/register: don't get a reference to the registered ring fd io_uring/tctx: clean up __io_uring_add_tctx_node() error handling io_uring/tctx: have io_uring_alloc_task_context() return tctx io_uring/timeout: use 'ctx' consistently io_uring/rw: clean up __io_read() obsolete comment and early returns io_uring/zcrx: use correct mmap off constants io_uring/zcrx: use dma_len for chunk size calculation io_uring/zcrx: don't clear not allocated niovs io_uring/zcrx: don't use mark0 for allocating xarray io_uring: cast id to u64 before shifting in io_allocate_rbuf_ring() io_uring/zcrx: reject REG_NODEV with large rx_buf_size io_uring/cancel: validate opcode for IORING_ASYNC_CANCEL_OP io_uring/rsrc: use io_cache_free() to free node io_uring/zcrx: rename zcrx [un]register functions io_uring/zcrx: check ctrl op payload struct sizes io_uring/zcrx: cache fallback availability in zcrx ctx io_uring/zcrx: warn on a repeated area append io_uring/zcrx: consolidate dma syncing io_uring/zcrx: netmem array as refiling format ... List of files: /linux/io_uring/loop.h Mon, 13 Apr 2026 23:22:30 +0000 Linus Torvalds <torvalds@linux-foundation.org> http://opengrok.net:8080/history/linux/io_uring/loop.h#033af2b3eb19c5ed96825572105bca3611635ada io_uring: introduce callback driven main loopThe io_uring_enter() has a fixed order of execution: it submitsrequests, waits for completions, and returns to the user. Allow tooptionally replace it with a custom loop driven by a callback calledloop_step. The basic requirements to the callback is that it should beable to submit requests, wait for completions, parse them and repeat.Most of the communication including parameter passing can be implementedvia shared memory.The callback should return IOU_LOOP_CONTINUE to continue execution orIOU_LOOP_STOP to return to the user space. Note that the kernel maydecide to prematurely terminate it as well, e.g. in case the process wassignalled or killed.The hook takes a structure with parameters. It can be used to ask thekernel to wait for CQEs by setting cq_wait_idx to the CQE index it wantsto wait for. Spurious wake ups are possible and even likely, the callbackis expected to handle it. There will be more parameters in the futurelike timeout.It can be used with kernel callbacks, for example, as a slow pathdeprecation mechanism overwiting SQEs and emulating the wantedbehaviour, however it's more useful together with BPF programsimplemented in following patches.Note that keeping it separately from the normal io_uring wait loopmakes things much simpler and cleaner. It keeps it in one place insteadof spreading a bunch of checks in different places including disablingthe submission path. It holds the lock by default, which is a better fitfor BPF synchronisation and the loop execution model. It nicely avoidsexisting quirks like forced wake ups on timeout request completion. Andit should be easier to implement new features.Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>Link: https://patch.msgid.link/a2d369aa1c9dd23ad7edac9220cffc563abcaed6.1772109579.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk> List of files: /linux/io_uring/loop.h Thu, 26 Feb 2026 12:48:38 +0000 Pavel Begunkov <asml.silence@gmail.com>