diff options
| -rw-r--r-- | fs/io_uring.c | 224 | ||||
| -rw-r--r-- | include/uapi/linux/io_uring.h | 14 |
2 files changed, 199 insertions, 39 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 1a58f2042815..a80b5c189c14 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -395,7 +395,9 @@ struct io_sr_msg { void __user *buf; }; int msg_flags; + int bgid; size_t len; + struct io_buffer *kbuf; }; struct io_open { @@ -490,6 +492,7 @@ enum { REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT, REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT, REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT, + REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT, REQ_F_LINK_NEXT_BIT, REQ_F_FAIL_LINK_BIT, @@ -506,6 +509,7 @@ enum { REQ_F_NEED_CLEANUP_BIT, REQ_F_OVERFLOW_BIT, REQ_F_POLLED_BIT, + REQ_F_BUFFER_SELECTED_BIT, }; enum { @@ -519,6 +523,8 @@ enum { REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT), /* IOSQE_ASYNC */ REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT), + /* IOSQE_BUFFER_SELECT */ + REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT), /* already grabbed next link */ REQ_F_LINK_NEXT = BIT(REQ_F_LINK_NEXT_BIT), @@ -550,6 +556,8 @@ enum { REQ_F_OVERFLOW = BIT(REQ_F_OVERFLOW_BIT), /* already went through poll handler */ REQ_F_POLLED = BIT(REQ_F_POLLED_BIT), + /* buffer already selected */ + REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT), }; struct async_poll { @@ -612,6 +620,7 @@ struct io_kiocb { struct callback_head task_work; struct hlist_node hash_node; struct async_poll *apoll; + int cflags; }; struct io_wq_work work; }; @@ -661,6 +670,8 @@ struct io_op_def { /* set if opcode supports polled "wait" */ unsigned pollin : 1; unsigned pollout : 1; + /* op supports buffer selection */ + unsigned buffer_select : 1; }; static const struct io_op_def io_op_defs[] = { @@ -770,6 +781,7 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, + .buffer_select = 1, }, [IORING_OP_WRITE] = { .needs_mm = 1, @@ -794,6 +806,7 @@ static const struct io_op_def io_op_defs[] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, + .buffer_select = 1, }, [IORING_OP_OPENAT2] = { .needs_file = 1, @@ -1170,7 +1183,7 @@ static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) if (cqe) { WRITE_ONCE(cqe->user_data, req->user_data); WRITE_ONCE(cqe->res, req->result); - WRITE_ONCE(cqe->flags, 0); + WRITE_ONCE(cqe->flags, req->cflags); } else { WRITE_ONCE(ctx->rings->cq_overflow, atomic_inc_return(&ctx->cached_cq_overflow)); @@ -1194,7 +1207,7 @@ static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) return cqe != NULL; } -static void io_cqring_fill_event(struct io_kiocb *req, long res) +static void __io_cqring_fill_event(struct io_kiocb *req, long res, long cflags) { struct io_ring_ctx *ctx = req->ctx; struct io_uring_cqe *cqe; @@ -1210,7 +1223,7 @@ static void io_cqring_fill_event(struct io_kiocb *req, long res) if (likely(cqe)) { WRITE_ONCE(cqe->user_data, req->user_data); WRITE_ONCE(cqe->res, res); - WRITE_ONCE(cqe->flags, 0); + WRITE_ONCE(cqe->flags, cflags); } else if (ctx->cq_overflow_flushed) { WRITE_ONCE(ctx->rings->cq_overflow, atomic_inc_return(&ctx->cached_cq_overflow)); @@ -1222,23 +1235,34 @@ static void io_cqring_fill_event(struct io_kiocb *req, long res) req->flags |= REQ_F_OVERFLOW; refcount_inc(&req->refs); req->result = res; + req->cflags = cflags; list_add_tail(&req->list, &ctx->cq_overflow_list); } } -static void io_cqring_add_event(struct io_kiocb *req, long res) +static void io_cqring_fill_event(struct io_kiocb *req, long res) +{ + __io_cqring_fill_event(req, res, 0); +} + +static void __io_cqring_add_event(struct io_kiocb *req, long res, long cflags) { struct io_ring_ctx *ctx = req->ctx; unsigned long flags; spin_lock_irqsave(&ctx->completion_lock, flags); - io_cqring_fill_event(req, res); + __io_cqring_fill_event(req, res, cflags); io_commit_cqring(ctx); spin_unlock_irqrestore(&ctx->completion_lock, flags); io_cqring_ev_posted(ctx); } +static void io_cqring_add_event(struct io_kiocb *req, long res) +{ + __io_cqring_add_event(req, res, 0); +} + static inline bool io_is_fallback_req(struct io_kiocb *req) { return req == (struct io_kiocb *) @@ -1660,6 +1684,18 @@ static inline bool io_req_multi_free(struct req_batch *rb, struct io_kiocb *req) return true; } +static int io_put_kbuf(struct io_kiocb *req) +{ + struct io_buffer *kbuf = (struct io_buffer *) req->rw.addr; + int cflags; + + cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT; + cflags |= IORING_CQE_F_BUFFER; + req->rw.addr = 0; + kfree(kbuf); + return cflags; +} + /* * Find and free completed poll iocbs */ @@ -1671,10 +1707,15 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, rb.to_free = rb.need_iter = 0; while (!list_empty(done)) { + int cflags = 0; + req = list_first_entry(done, struct io_kiocb, list); list_del(&req->list); - io_cqring_fill_event(req, req->result); + if (req->flags & REQ_F_BUFFER_SELECTED) + cflags = io_put_kbuf(req); + + __io_cqring_fill_event(req, req->result, cflags); (*nr_events)++; if (refcount_dec_and_test(&req->refs) && @@ -1849,13 +1890,16 @@ static inline void req_set_fail_links(struct io_kiocb *req) static void io_complete_rw_common(struct kiocb *kiocb, long res) { struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); + int cflags = 0; if (kiocb->ki_flags & IOCB_WRITE) kiocb_end_write(req); if (res != req->result) req_set_fail_links(req); - io_cqring_add_event(req, res); + if (req->flags & REQ_F_BUFFER_SELECTED) + cflags = io_put_kbuf(req); + __io_cqring_add_event(req, res, cflags); } static void io_complete_rw(struct kiocb *kiocb, long res, long res2) @@ -2033,7 +2077,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, req->rw.addr = READ_ONCE(sqe->addr); req->rw.len = READ_ONCE(sqe->len); - /* we own ->private, reuse it for the buffer index */ + /* we own ->private, reuse it for the buffer index / buffer ID */ req->rw.kiocb.private = (void *) (unsigned long) READ_ONCE(sqe->buf_index); return 0; @@ -2146,8 +2190,61 @@ static ssize_t io_import_fixed(struct io_kiocb *req, int rw, return len; } +static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock) +{ + if (needs_lock) + mutex_unlock(&ctx->uring_lock); +} + +static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock) +{ + /* + * "Normal" inline submissions always hold the uring_lock, since we + * grab it from the system call. Same is true for the SQPOLL offload. + * The only exception is when we've detached the request and issue it + * from an async worker thread, grab the lock for that case. + */ + if (needs_lock) + mutex_lock(&ctx->uring_lock); +} + +static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len, + int bgid, struct io_buffer *kbuf, + bool needs_lock) +{ + struct io_buffer *head; + + if (req->flags & REQ_F_BUFFER_SELECTED) + return kbuf; + + io_ring_submit_lock(req->ctx, needs_lock); + + lockdep_assert_held(&req->ctx->uring_lock); + + head = idr_find(&req->ctx->io_buffer_idr, bgid); + if (head) { + if (!list_empty(&head->list)) { + kbuf = list_last_entry(&head->list, struct io_buffer, + list); + list_del(&kbuf->list); + } else { + kbuf = head; + idr_remove(&req->ctx->io_buffer_idr, bgid); + } + if (*len > kbuf->len) + *len = kbuf->len; + } else { + kbuf = ERR_PTR(-ENOBUFS); + } + + io_ring_submit_unlock(req->ctx, needs_lock); + + return kbuf; +} + static ssize_t io_import_iovec(int rw, struct io_kiocb *req, - struct iovec **iovec, struct iov_iter *iter) + struct iovec **iovec, struct iov_iter *iter, + bool needs_lock) { void __user *buf = u64_to_user_ptr(req->rw.addr); size_t sqe_len = req->rw.len; @@ -2159,12 +2256,29 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req, return io_import_fixed(req, rw, iter); } - /* buffer index only valid with fixed read/write */ - if (req->rw.kiocb.private) + /* buffer index only valid with fixed read/write, or buffer select */ + if (req->rw.kiocb.private && !(req->flags & REQ_F_BUFFER_SELECT)) return -EINVAL; if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) { ssize_t ret; + + if (req->flags & REQ_F_BUFFER_SELECT) { + struct io_buffer *kbuf = (struct io_buffer *) req->rw.addr; + int bgid; + + bgid = (int) (unsigned long) req->rw.kiocb.private; + kbuf = io_buffer_select(req, &sqe_len, bgid, kbuf, + needs_lock); + if (IS_ERR(kbuf)) { + *iovec = NULL; + return PTR_ERR(kbuf); + } + req->rw.addr = (u64) kbuf; + req->flags |= REQ_F_BUFFER_SELECTED; + buf = u64_to_user_ptr(kbuf->addr); + } + ret = import_single_range(rw, buf, sqe_len, *iovec, iter); *iovec = NULL; return ret < 0 ? ret : sqe_len; @@ -2307,7 +2421,7 @@ static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, io = req->io; io->rw.iov = io->rw.fast_iov; req->io = NULL; - ret = io_import_iovec(READ, req, &io->rw.iov, &iter); + ret = io_import_iovec(READ, req, &io->rw.iov, &iter, !force_nonblock); req->io = io; if (ret < 0) return ret; @@ -2324,7 +2438,7 @@ static int io_read(struct io_kiocb *req, bool force_nonblock) size_t iov_count; ssize_t io_size, ret; - ret = io_import_iovec(READ, req, &iovec, &iter); + ret = io_import_iovec(READ, req, &iovec, &iter, !force_nonblock); if (ret < 0) return ret; @@ -2396,7 +2510,7 @@ static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, io = req->io; io->rw.iov = io->rw.fast_iov; req->io = NULL; - ret = io_import_iovec(WRITE, req, &io->rw.iov, &iter); + ret = io_import_iovec(WRITE, req, &io->rw.iov, &iter, !force_nonblock); req->io = io; if (ret < 0) return ret; @@ -2413,7 +2527,7 @@ static int io_write(struct io_kiocb *req, bool force_nonblock) size_t iov_count; ssize_t ret, io_size; - ret = io_import_iovec(WRITE, req, &iovec, &iter); + ret = io_import_iovec(WRITE, req, &iovec, &iter, !force_nonblock); if (ret < 0) return ret; @@ -2850,24 +2964,6 @@ static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head) return i ? i : -ENOMEM; } -static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock) -{ - if (needs_lock) - mutex_unlock(&ctx->uring_lock); -} - -static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock) -{ - /* - * "Normal" inline submissions always hold the uring_lock, since we - * grab it from the system call. Same is true for the SQPOLL offload. - * The only exception is when we've detached the request and issue it - * from an async worker thread, grab the lock for that case. - */ - if (needs_lock) - mutex_lock(&ctx->uring_lock); -} - static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock) { struct io_provide_buf *p = &req->pbuf; @@ -3390,6 +3486,27 @@ static int io_send(struct io_kiocb *req, bool force_nonblock) #endif } +static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req, + int *cflags, bool needs_lock) +{ + struct io_sr_msg *sr = &req->sr_msg; + struct io_buffer *kbuf; + + if (!(req->flags & REQ_F_BUFFER_SELECT)) + return NULL; + + kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock); + if (IS_ERR(kbuf)) + return kbuf; + + sr->kbuf = kbuf; + req->flags |= REQ_F_BUFFER_SELECTED; + + *cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT; + *cflags |= IORING_CQE_F_BUFFER; + return kbuf; +} + static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { @@ -3401,6 +3518,7 @@ static int io_recvmsg_prep(struct io_kiocb *req, sr->msg_flags = READ_ONCE(sqe->msg_flags); sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); + sr->bgid = READ_ONCE(sqe->buf_group); #ifdef CONFIG_COMPAT if (req->ctx->compat) @@ -3490,8 +3608,9 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock) static int io_recv(struct io_kiocb *req, bool force_nonblock) { #if defined(CONFIG_NET) + struct io_buffer *kbuf = NULL; struct socket *sock; - int ret; + int ret, cflags = 0; if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; @@ -3499,15 +3618,25 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock) sock = sock_from_file(req->file, &ret); if (sock) { struct io_sr_msg *sr = &req->sr_msg; + void __user *buf = sr->buf; struct msghdr msg; struct iovec iov; unsigned flags; - ret = import_single_range(READ, sr->buf, sr->len, &iov, + kbuf = io_recv_buffer_select(req, &cflags, !force_nonblock); + if (IS_ERR(kbuf)) + return PTR_ERR(kbuf); + else if (kbuf) + buf = u64_to_user_ptr(kbuf->addr); + + ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter); - if (ret) + if (ret) { + kfree(kbuf); return ret; + } + req->flags |= REQ_F_NEED_CLEANUP; msg.msg_name = NULL; msg.msg_control = NULL; msg.msg_controllen = 0; @@ -3528,7 +3657,9 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock) ret = -EINTR; } - io_cqring_add_event(req, ret); + kfree(kbuf); + req->flags &= ~REQ_F_NEED_CLEANUP; + __io_cqring_add_event(req, ret, cflags); if (ret < 0) req_set_fail_links(req); io_put_req(req); @@ -4566,6 +4697,9 @@ static void io_cleanup_req(struct io_kiocb *req) case IORING_OP_READV: case IORING_OP_READ_FIXED: case IORING_OP_READ: + if (req->flags & REQ_F_BUFFER_SELECTED) + kfree((void *)(unsigned long)req->rw.addr); + /* fallthrough */ case IORING_OP_WRITEV: case IORING_OP_WRITE_FIXED: case IORING_OP_WRITE: @@ -4577,6 +4711,10 @@ static void io_cleanup_req(struct io_kiocb *req) if (io->msg.iov != io->msg.fast_iov) kfree(io->msg.iov); break; + case IORING_OP_RECV: + if (req->flags & REQ_F_BUFFER_SELECTED) + kfree(req->sr_msg.kbuf); + break; case IORING_OP_OPENAT: case IORING_OP_OPENAT2: case IORING_OP_STATX: @@ -5154,7 +5292,8 @@ static inline void io_queue_link_head(struct io_kiocb *req) } #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \ - IOSQE_IO_HARDLINK | IOSQE_ASYNC) + IOSQE_IO_HARDLINK | IOSQE_ASYNC | \ + IOSQE_BUFFER_SELECT) static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, struct io_submit_state *state, struct io_kiocb **link) @@ -5171,6 +5310,12 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, goto err_req; } + if ((sqe_flags & IOSQE_BUFFER_SELECT) && + !io_op_defs[req->opcode].buffer_select) { + ret = -EOPNOTSUPP; + goto err_req; + } + id = READ_ONCE(sqe->personality); if (id) { req->work.creds = idr_find(&ctx->personality_idr, id); @@ -5183,7 +5328,8 @@ static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, /* same numerical values with corresponding REQ_F_*, safe to copy */ req->flags |= sqe_flags & (IOSQE_IO_DRAIN | IOSQE_IO_HARDLINK | - IOSQE_ASYNC | IOSQE_FIXED_FILE); + IOSQE_ASYNC | IOSQE_FIXED_FILE | + IOSQE_BUFFER_SELECT); ret = io_req_set_file(state, req, sqe); if (unlikely(ret)) { diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index bc34a57a660b..9b263d9b24e6 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -66,6 +66,7 @@ enum { IOSQE_IO_LINK_BIT, IOSQE_IO_HARDLINK_BIT, IOSQE_ASYNC_BIT, + IOSQE_BUFFER_SELECT_BIT, }; /* @@ -81,6 +82,8 @@ enum { #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT) /* always go async */ #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT) +/* select buffer from sqe->buf_group */ +#define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT) /* * io_uring_setup() flags @@ -156,6 +159,17 @@ struct io_uring_cqe { }; /* + * cqe->flags + * + * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID + */ +#define IORING_CQE_F_BUFFER (1U << 0) + +enum { + IORING_CQE_BUFFER_SHIFT = 16, +}; + +/* * Magic offsets for the application to mmap the data it needs */ #define IORING_OFF_SQ_RING 0ULL |