Added new READV_PI/WRITEV_PI operations to io_uring. Added new pi_addr & pi_len fields to SQE struct. Added new IOCB_USE_PI flag to kiocb struct. Use kiocb->private pointer to pass PI data iterator to low layer. Signed-off-by: Alexander V. Buev <a.buev@xxxxxxxxx> --- include/linux/fs.h | 1 + include/uapi/linux/io_uring.h | 6 + include/uapi/linux/uio.h | 3 +- io_uring/Makefile | 3 +- io_uring/io_uring.c | 2 + io_uring/opdef.c | 27 ++ io_uring/rw.h | 4 + io_uring/rw_pi.c | 630 ++++++++++++++++++++++++++++++++++ io_uring/rw_pi.h | 34 ++ 9 files changed, 708 insertions(+), 2 deletions(-) create mode 100644 io_uring/rw_pi.c create mode 100644 io_uring/rw_pi.h diff --git a/include/linux/fs.h b/include/linux/fs.h index 9eced4cc286e..a28b12a22750 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -337,6 +337,7 @@ enum rw_hint { #define IOCB_NOIO (1 << 20) /* can use bio alloc cache */ #define IOCB_ALLOC_CACHE (1 << 21) +#define IOCB_USE_PI (1 << 22) struct kiocb { struct file *ki_filp; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 6b83177fd41d..a4158e48cecb 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -80,6 +80,10 @@ struct io_uring_sqe { __u64 addr3; __u64 __pad2[1]; }; + struct { + __u64 pi_addr; + __u32 pi_len; + }; /* * If the ring is initialized with IORING_SETUP_SQE128, then * this field is used for 80 bytes of arbitrary command data @@ -206,6 +210,8 @@ enum io_uring_op { IORING_OP_SOCKET, IORING_OP_URING_CMD, IORING_OP_SEND_ZC, + IORING_OP_READV_PI, + IORING_OP_WRITEV_PI, /* this goes last, obviously */ IORING_OP_LAST, diff --git a/include/uapi/linux/uio.h b/include/uapi/linux/uio.h index 059b1a9147f4..c9eaaa6cdb0f 100644 --- a/include/uapi/linux/uio.h +++ b/include/uapi/linux/uio.h @@ -23,9 +23,10 @@ struct iovec /* * UIO_MAXIOV shall be at least 16 1003.1g (5.4.1.1) */ - + #define UIO_FASTIOV 8 #define UIO_MAXIOV 1024 +#define UIO_FASTIOV_PI 1 #endif /* _UAPI__LINUX_UIO_H */ diff --git a/io_uring/Makefile b/io_uring/Makefile index 8cc8e5387a75..8c01546c2bcf 100644 --- a/io_uring/Makefile +++ b/io_uring/Makefile @@ -7,5 +7,6 @@ obj-$(CONFIG_IO_URING) += io_uring.o xattr.o nop.o fs.o splice.o \ openclose.o uring_cmd.o epoll.o \ statx.o net.o msg_ring.o timeout.o \ sqpoll.o fdinfo.o tctx.o poll.o \ - cancel.o kbuf.o rsrc.o rw.o opdef.o notif.o + cancel.o kbuf.o rsrc.o rw.o opdef.o \ + notif.o rw_pi.o obj-$(CONFIG_IO_WQ) += io-wq.o diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index b9640ad5069f..b2f451e18646 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3927,7 +3927,9 @@ static int __init io_uring_init(void) BUILD_BUG_SQE_ELEM(44, __u16, addr_len); BUILD_BUG_SQE_ELEM(46, __u16, __pad3[0]); BUILD_BUG_SQE_ELEM(48, __u64, addr3); + BUILD_BUG_SQE_ELEM(48, __u64, pi_addr); BUILD_BUG_SQE_ELEM_SIZE(48, 0, cmd); + BUILD_BUG_SQE_ELEM(56, __u32, pi_len); BUILD_BUG_SQE_ELEM(56, __u64, __pad2); BUILD_BUG_ON(sizeof(struct io_uring_files_update) != diff --git a/io_uring/opdef.c b/io_uring/opdef.c index c61494e0a602..da2b12a44995 100644 --- a/io_uring/opdef.c +++ b/io_uring/opdef.c @@ -33,6 +33,7 @@ #include "poll.h" #include "cancel.h" #include "rw.h" +#include "rw_pi.h" static int io_no_issue(struct io_kiocb *req, unsigned int issue_flags) { @@ -488,6 +489,32 @@ const struct io_op_def io_op_defs[] = { .prep = io_eopnotsupp_prep, #endif }, + [IORING_OP_READV_PI] = { + .needs_file = 1, + .plug = 1, + .audit_skip = 1, + .ioprio = 1, + .iopoll = 1, + .async_size = sizeof(struct io_async_rw_pi), + .name = "READV_PI", + .prep = io_prep_rw_pi, + .issue = io_readv_pi, + .prep_async = io_readv_pi_prep_async, + .cleanup = io_readv_writev_cleanup, + }, + [IORING_OP_WRITEV_PI] = { + .needs_file = 1, + .plug = 1, + .audit_skip = 1, + .ioprio = 1, + .iopoll = 1, + .async_size = sizeof(struct io_async_rw_pi), + .name = "WRITEV_PI", + .prep = io_prep_rw_pi, + .issue = io_writev_pi, + .prep_async = io_writev_pi_prep_async, + .cleanup = io_readv_writev_cleanup, + }, }; const char *io_uring_get_opcode(u8 opcode) diff --git a/io_uring/rw.h b/io_uring/rw.h index 0204c3fcafa5..c00ece398540 100644 --- a/io_uring/rw.h +++ b/io_uring/rw.h @@ -1,4 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 +#ifndef IOU_RW_H +#define IOU_RW_H #include <linux/pagemap.h> @@ -21,3 +23,5 @@ int io_readv_prep_async(struct io_kiocb *req); int io_write(struct io_kiocb *req, unsigned int issue_flags); int io_writev_prep_async(struct io_kiocb *req); void io_readv_writev_cleanup(struct io_kiocb *req); + +#endif diff --git a/io_uring/rw_pi.c b/io_uring/rw_pi.c new file mode 100644 index 000000000000..ecee133d709c --- /dev/null +++ b/io_uring/rw_pi.c @@ -0,0 +1,630 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/file.h> +#include <linux/blk-mq.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/fsnotify.h> +#include <linux/poll.h> +#include <linux/nospec.h> +#include <linux/compat.h> +#include <linux/io_uring.h> + +#include <uapi/linux/io_uring.h> + +#include "io_uring.h" +#include "opdef.h" +#include "rw_pi.h" + +#define io_kiocb_to_kiocb(req, type) \ + (&((type *)io_kiocb_to_cmd(req, type))->kiocb) +#define DATA (0) +#define PI (1) + +#define u64_to_ptr(x) ( \ +{ \ + typecheck(u64, (x)); \ + (void *)(uintptr_t)(x); \ +}) + +struct io_rw_pi { + struct kiocb kiocb; + u64 addr; + u32 nr_segs; + u32 nr_pi_segs; +}; + +static inline +void io_rw_pi_state_iter_restore(struct io_rw_state *data, struct __io_rw_pi_state *pi) +{ + iov_iter_restore(&data->iter, &data->iter_state); + iov_iter_restore(&pi->iter, &pi->iter_state); +} + +static inline +void io_rw_pi_state_iter_save(struct io_rw_state *data, struct __io_rw_pi_state *pi) +{ + iov_iter_save_state(&data->iter, &data->iter_state); + iov_iter_save_state(&pi->iter, &pi->iter_state); +} + +static inline bool io_file_supports_nowait(struct io_kiocb *req) +{ + return req->flags & REQ_F_SUPPORT_NOWAIT; +} + +static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) +{ + switch (ret) { + case -EIOCBQUEUED: + break; + case -ERESTARTSYS: + case -ERESTARTNOINTR: + case -ERESTARTNOHAND: + case -ERESTART_RESTARTBLOCK: + /* + * We can't just restart the syscall, since previously + * submitted sqes may already be in progress. Just fail this + * IO with EINTR. + */ + ret = -EINTR; + fallthrough; + default: + kiocb->ki_complete(kiocb, ret); + } +} + +static inline loff_t *io_kiocb_update_pos(struct io_kiocb *req) +{ + struct io_rw_pi *rw = io_kiocb_to_cmd(req, struct io_rw_pi); + + if (rw->kiocb.ki_pos != -1) + return &rw->kiocb.ki_pos; + + if (!(req->file->f_mode & FMODE_STREAM)) { + req->flags |= REQ_F_CUR_POS; + rw->kiocb.ki_pos = req->file->f_pos; + return &rw->kiocb.ki_pos; + } + + rw->kiocb.ki_pos = 0; + return NULL; +} + +static void io_req_task_queue_reissue(struct io_kiocb *req) +{ + req->io_task_work.func = io_queue_iowq; + io_req_task_work_add(req); +} + +static bool io_resubmit_prep(struct io_kiocb *req) +{ + struct io_async_rw_pi *arw = req->async_data; + + if (!req_has_async_data(req)) + return !io_req_prep_async(req); + io_rw_pi_state_iter_restore(&arw->data.s, &arw->pi.s); + return true; +} + +static bool io_rw_should_reissue(struct io_kiocb *req) +{ + struct io_ring_ctx *ctx = req->ctx; + + if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() && + !(ctx->flags & IORING_SETUP_IOPOLL))) + return false; + /* + * If ref is dying, we might be running poll reap from the exit work. + * Don't attempt to reissue from that path, just let it fail with + * -EAGAIN. + */ + if (percpu_ref_is_dying(&ctx->refs)) + return false; + /* + * Play it safe and assume not safe to re-import and reissue if we're + * not in the original thread group (or in task context). + */ + if (!same_thread_group(req->task, current) || !in_task()) + return false; + return true; +} + +static bool __io_complete_rw_common(struct io_kiocb *req, long res) +{ + struct io_rw_pi *rw = io_kiocb_to_cmd(req, struct io_rw_pi); + + if (rw->kiocb.ki_flags & IOCB_WRITE) + fsnotify_modify(req->file); + else + fsnotify_access(req->file); + + if (unlikely(res != req->cqe.res)) { + if ((res == -EAGAIN || res == -EOPNOTSUPP) && + io_rw_should_reissue(req)) { + req->flags |= REQ_F_REISSUE | REQ_F_PARTIAL_IO; + return true; + } + req_set_fail(req); + req->cqe.res = res; + } + return false; +} + +static inline +unsigned int io_fixup_rw_res(struct io_kiocb *req, unsigned int res) +{ + struct io_async_rw_pi *arw = req->async_data; + + /* add previously done IO, if any */ + if (req_has_async_data(req) && arw->data.bytes_done > 0) { + if (res < 0) + res = arw->data.bytes_done; + else + res += arw->data.bytes_done; + } + return res; +} + +static void io_complete_rw(struct kiocb *kiocb, long res) +{ + struct io_rw_pi *rw = container_of(kiocb, struct io_rw_pi, kiocb); + struct io_kiocb *req = cmd_to_io_kiocb(rw); + + if (__io_complete_rw_common(req, res)) + return; + io_req_set_res(req, io_fixup_rw_res(req, res), 0); + req->io_task_work.func = io_req_task_complete; + io_req_task_work_add(req); +} + +static void io_complete_rw_iopoll(struct kiocb *kiocb, long res) +{ + struct io_rw_pi *rw = container_of(kiocb, struct io_rw_pi, kiocb); + struct io_kiocb *req = cmd_to_io_kiocb(rw); + + if (unlikely(res != req->cqe.res)) { + if (res == -EAGAIN && io_rw_should_reissue(req)) { + req->flags |= REQ_F_REISSUE | REQ_F_PARTIAL_IO; + return; + } + req->cqe.res = res; + } + + /* order with io_iopoll_complete() checking ->iopoll_completed */ + smp_store_release(&req->iopoll_completed, 1); +} + +static int kiocb_done(struct io_kiocb *req, ssize_t ret, + unsigned int issue_flags) +{ + struct io_rw_pi *rw = io_kiocb_to_cmd(req, struct io_rw_pi); + unsigned int final_ret = io_fixup_rw_res(req, ret); + + if (req->flags & REQ_F_CUR_POS) + req->file->f_pos = rw->kiocb.ki_pos; + if (ret >= 0 && (rw->kiocb.ki_complete == io_complete_rw)) { + if (!__io_complete_rw_common(req, ret)) { + io_req_set_res(req, final_ret, 0); + return IOU_OK; + } + } else { + io_rw_done(&rw->kiocb, ret); + } + + if (req->flags & REQ_F_REISSUE) { + req->flags &= ~REQ_F_REISSUE; + if (io_resubmit_prep(req)) + io_req_task_queue_reissue(req); + else + io_req_task_queue_fail(req, ret); + } + return IOU_ISSUE_SKIP_COMPLETE; +} + +int io_prep_rw_pi(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_rw_pi *rw = io_kiocb_to_cmd(req, struct io_rw_pi); + struct kiocb *kiocb = &rw->kiocb; + unsigned int ioprio; + int ret; + + kiocb->ki_flags = 0; + ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags)); + if (unlikely(ret)) + return ret; + + kiocb->ki_pos = READ_ONCE(sqe->off); + + ioprio = READ_ONCE(sqe->ioprio); + if (ioprio) { + ret = ioprio_check_cap(ioprio); + if (ret) + return ret; + + kiocb->ki_ioprio = ioprio; + } else { + kiocb->ki_ioprio = get_current_ioprio(); + } + + req->imu = NULL; + + /* save data iovec pointer & len */ + rw->addr = (uintptr_t)READ_ONCE(sqe->addr); + rw->nr_segs = READ_ONCE(sqe->len); + + /* save pi iovec pointer & len */ + rw->kiocb.private = u64_to_ptr(READ_ONCE(sqe->pi_addr)); + rw->nr_pi_segs = READ_ONCE(sqe->pi_len); + + kiocb->ki_flags |= IOCB_USE_PI; + + return 0; +} + + +static inline int +io_import_iovecs_pi(int io_dir, struct io_kiocb *req, struct iovec **iovec, + struct io_rw_state *s_data, struct __io_rw_pi_state *s_pi) +{ + struct io_rw_pi *rw = io_kiocb_to_cmd(req, struct io_rw_pi); + struct iovec __user *uvec; + ssize_t ret; + + /* data */ + uvec = (struct iovec __user *)u64_to_user_ptr(rw->addr); + iovec[DATA] = s_data->fast_iov; + ret = __import_iovec(io_dir, uvec, rw->nr_segs, + UIO_FASTIOV, iovec + DATA, + &s_data->iter, req->ctx->compat); + + if (unlikely(ret <= 0)) + return (ret) ? ret : -EINVAL; + /* pi */ + uvec = (struct iovec __user *)rw->kiocb.private; + iovec[PI] = s_pi->fast_iov; + ret = __import_iovec(io_dir, uvec, rw->nr_pi_segs, + UIO_FASTIOV_PI, iovec + PI, + &s_pi->iter, req->ctx->compat); + if (unlikely(ret <= 0)) { + if (iovec[DATA]) + kfree(iovec[DATA]); + return (ret) ? ret : -EINVAL; + } + + /* save states */ + io_rw_pi_state_iter_save(s_data, s_pi); + + return 0; +} + +static inline void +io_setup_async_state(struct io_rw_state *async_s, const struct io_rw_state *s) +{ + unsigned int iov_off = 0; + + async_s->iter.iov = async_s->fast_iov; + if (s->iter.iov != s->fast_iov) { + iov_off = s->iter.iov - s->fast_iov; + async_s->iter.iov += iov_off; + } + if (async_s->fast_iov != s->fast_iov) { + memcpy(async_s->fast_iov + iov_off, s->fast_iov + iov_off, + sizeof(struct iovec) * s->iter.nr_segs); + } +} + +static int +io_setup_async_rw_pi(struct io_kiocb *req, struct iovec * const *iovec, + struct io_rw_state *s_data, + struct __io_rw_pi_state *s_pi) +{ + struct io_async_rw_pi *arw; + + if (req_has_async_data(req)) + return 0; + + if (io_alloc_async_data(req)) + return -ENOMEM; + + arw = req->async_data; + + /* data */ + arw->data.s.iter = s_data->iter; + arw->data.free_iovec = iovec[DATA]; + arw->data.bytes_done = 0; + + if (iovec[DATA]) + req->flags |= REQ_F_NEED_CLEANUP; + else + io_setup_async_state(&arw->data.s, s_data); + + /* pi */ + arw->pi.s.iter = s_pi->iter; + arw->pi.free_iovec = iovec[PI]; + + if (iovec[PI]) + req->flags |= REQ_F_NEED_CLEANUP; + else { + io_setup_async_state((struct io_rw_state *)&arw->pi.s, + (const struct io_rw_state *)s_pi); + } + + /* save states */ + io_rw_pi_state_iter_save(&arw->data.s, &arw->pi.s); + + return 0; +} + +static inline int io_rw_pi_prep_async(struct io_kiocb *req, int io_dir) +{ + int ret = 0; + struct io_async_rw_pi *arw = req->async_data; + struct iovec *iovec[2]; + + ret = io_import_iovecs_pi(io_dir, req, iovec, + &arw->data.s, &arw->pi.s); + if (unlikely(ret < 0)) + return ret; + + arw->data.bytes_done = 0; + arw->data.free_iovec = iovec[DATA]; + arw->pi.free_iovec = iovec[PI]; + + if (iovec[DATA] || iovec[PI]) + req->flags |= REQ_F_NEED_CLEANUP; + + return 0; +} + + +int io_readv_pi_prep_async(struct io_kiocb *req) +{ + return io_rw_pi_prep_async(req, READ); +} + +int io_writev_pi_prep_async(struct io_kiocb *req) +{ + return io_rw_pi_prep_async(req, WRITE); +} + +static int io_rw_pi_init_file(struct io_kiocb *req, fmode_t mode) +{ + struct kiocb *kiocb = io_kiocb_to_kiocb(req, struct io_rw_pi); + struct io_ring_ctx *ctx = req->ctx; + struct file *file = req->file; + int flags; + + if (unlikely(!file || !(file->f_mode & mode))) + return -EBADF; + + if (unlikely(!S_ISBLK(file_inode(req->file)->i_mode))) + return -EINVAL; + + if (unlikely(!(file->f_flags & O_DIRECT))) + return -EINVAL; + + if (!io_req_ffs_set(req)) + req->flags |= io_file_get_flags(file) << REQ_F_SUPPORT_NOWAIT_BIT; + + flags = kiocb->ki_flags; + kiocb->ki_flags = iocb_flags(file); + kiocb->ki_flags |= flags; + + /* + * If the file is marked O_NONBLOCK, still allow retry for it if it + * supports async. Otherwise it's impossible to use O_NONBLOCK files + * reliably. If not, or it IOCB_NOWAIT is set, don't retry. + */ + if ((kiocb->ki_flags & IOCB_NOWAIT) || + ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req))) + req->flags |= REQ_F_NOWAIT; + + if (ctx->flags & IORING_SETUP_IOPOLL) { + if (!(kiocb->ki_flags & IOCB_DIRECT) || !file->f_op->iopoll) + return -EOPNOTSUPP; + + kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE; + kiocb->ki_complete = io_complete_rw_iopoll; + req->iopoll_completed = 0; + } else { + if (kiocb->ki_flags & IOCB_HIPRI) + return -EINVAL; + kiocb->ki_complete = io_complete_rw; + } + + return 0; +} + +void io_readv_writev_pi_cleanup(struct io_kiocb *req) +{ + struct io_async_rw_pi *arw = req->async_data; + + kfree(arw->data.free_iovec); + kfree(arw->pi.free_iovec); +} + +int io_readv_pi(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_rw_pi_state s; + struct io_rw_state *s_data; + struct __io_rw_pi_state *s_pi; + struct iovec *iovec[2]; + struct kiocb *kiocb = io_kiocb_to_kiocb(req, struct io_rw_pi); + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + ssize_t ret; + loff_t *ppos; + + if (!req_has_async_data(req)) { + s_data = &s.data; + s_pi = &s.pi; + ret = io_import_iovecs_pi(READ, req, iovec, s_data, s_pi); + if (unlikely(ret < 0)) + return ret; + } else { + struct io_async_rw_pi *arw = req->async_data; + + iovec[DATA] = iovec[PI] = NULL; + s_data = &arw->data.s; + s_pi = &arw->pi.s; + io_rw_pi_state_iter_restore(s_data, s_pi); + } + kiocb->private = &s_pi->iter; + + ret = io_rw_pi_init_file(req, FMODE_READ); + if (unlikely(ret)) + goto out_free; + + req->cqe.res = iov_iter_count(&s_data->iter); + if (force_nonblock) { + /* If the file doesn't support async, just async punt */ + if (unlikely(!io_file_supports_nowait(req))) { + ret = io_setup_async_rw_pi(req, iovec, s_data, s_pi); + return ret ?: -EAGAIN; + } + kiocb->ki_flags |= IOCB_NOWAIT; + } else { + /* Ensure we clear previously set non-block flag */ + kiocb->ki_flags &= ~IOCB_NOWAIT; + } + + ppos = io_kiocb_update_pos(req); + + ret = rw_verify_area(READ, req->file, ppos, req->cqe.res); + if (unlikely(ret)) + goto out_free; + + if (likely(req->file->f_op->read_iter)) + ret = call_read_iter(req->file, kiocb, &s_data->iter); + else + ret = -EINVAL; + + if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) { + req->flags &= ~REQ_F_REISSUE; + + /* IOPOLL retry should happen for io-wq threads */ + if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL)) + goto done; + /* no retry on NONBLOCK nor RWF_NOWAIT */ + if (req->flags & REQ_F_NOWAIT) + goto done; + ret = 0; + } else if (ret == -EIOCBQUEUED) { + ret = IOU_ISSUE_SKIP_COMPLETE; + goto out_free; + } + +done: + /* it's faster to check here then delegate to kfree */ + if (iovec[DATA]) + kfree(iovec[DATA]); + if (iovec[PI]) + kfree(iovec[PI]); + return kiocb_done(req, ret, issue_flags); +out_free: + if (iovec[DATA]) + kfree(iovec[DATA]); + if (iovec[PI]) + kfree(iovec[PI]); + return ret; +} + +int io_writev_pi(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_rw_pi_state s; + struct io_rw_state *s_data; + struct __io_rw_pi_state *s_pi; + struct iovec *iovec[2]; + struct kiocb *kiocb = io_kiocb_to_kiocb(req, struct io_rw_pi); + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + ssize_t ret, ret2; + loff_t *ppos; + + if (!req_has_async_data(req)) { + s_data = &s.data; + s_pi = &s.pi; + ret = io_import_iovecs_pi(WRITE, req, iovec, s_data, s_pi); + if (unlikely(ret < 0)) + return ret; + } else { + struct io_async_rw_pi *arw = req->async_data; + + iovec[DATA] = iovec[PI] = 0; + s_data = &arw->data.s; + s_pi = &arw->pi.s; + io_rw_pi_state_iter_restore(s_data, s_pi); + } + kiocb->private = &s_pi->iter; + + ret = io_rw_pi_init_file(req, FMODE_WRITE); + if (unlikely(ret)) + goto out_free; + + req->cqe.res = iov_iter_count(&s_data->iter); + + if (force_nonblock) { + /* If the file doesn't support async, just async punt */ + if (unlikely(!io_file_supports_nowait(req))) + goto copy_iov; + + kiocb->ki_flags |= IOCB_NOWAIT; + } else { + /* Ensure we clear previously set non-block flag */ + kiocb->ki_flags &= ~IOCB_NOWAIT; + } + + ppos = io_kiocb_update_pos(req); + + ret = rw_verify_area(WRITE, req->file, ppos, req->cqe.res); + if (unlikely(ret)) + goto out_free; + + kiocb->ki_flags |= IOCB_WRITE; + + if (likely(req->file->f_op->write_iter)) + ret2 = call_write_iter(req->file, kiocb, &s_data->iter); + else + ret2 = -EINVAL; + + if (req->flags & REQ_F_REISSUE) { + req->flags &= ~REQ_F_REISSUE; + ret2 = -EAGAIN; + } + + /* + * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just + * retry them without IOCB_NOWAIT. + */ + if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT)) + ret2 = -EAGAIN; + /* no retry on NONBLOCK nor RWF_NOWAIT */ + if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT)) + goto done; + if (!force_nonblock || ret2 != -EAGAIN) { + if (ret2 == -EIOCBQUEUED) { + ret = IOU_ISSUE_SKIP_COMPLETE; + goto out_free; + } + /* IOPOLL retry should happen for io-wq threads */ + if (ret2 == -EAGAIN && (req->ctx->flags & IORING_SETUP_IOPOLL)) + goto copy_iov; + +done: + ret = kiocb_done(req, ret2, issue_flags); + } else { +copy_iov: + io_rw_pi_state_iter_restore(s_data, s_pi); + ret = io_setup_async_rw_pi(req, iovec, s_data, s_pi); + return ret ?: -EAGAIN; + } +out_free: + /* it's reportedly faster than delegating the null check to kfree() */ + if (iovec[DATA]) + kfree(iovec[DATA]); + if (iovec[PI]) + kfree(iovec[PI]); + return ret; +} + diff --git a/io_uring/rw_pi.h b/io_uring/rw_pi.h new file mode 100644 index 000000000000..f635da982484 --- /dev/null +++ b/io_uring/rw_pi.h @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef IOU_RW_PI_H +#define IOU_RW_PI_H + +#include "rw.h" + +struct __io_rw_pi_state { + struct iov_iter iter; + struct iov_iter_state iter_state; + struct iovec fast_iov[UIO_FASTIOV_PI]; +}; + +struct io_rw_pi_state { + struct io_rw_state data; + struct __io_rw_pi_state pi; +}; + +struct __io_async_rw_pi { + const struct iovec *free_iovec; + struct __io_rw_pi_state s; +}; + +struct io_async_rw_pi { + struct io_async_rw data; + struct __io_async_rw_pi pi; +}; + +int io_prep_rw_pi(struct io_kiocb *req, const struct io_uring_sqe *sqe); +int io_readv_pi(struct io_kiocb *req, unsigned int issue_flags); +int io_readv_pi_prep_async(struct io_kiocb *req); +int io_writev_pi(struct io_kiocb *req, unsigned int issue_flags); +int io_writev_pi_prep_async(struct io_kiocb *req); +void io_readv_writev_pi_cleanup(struct io_kiocb *req); +#endif -- 2.30.2