diff options
| -rw-r--r-- | fs/io_uring.c | 91 | ||||
| -rw-r--r-- | include/uapi/linux/io_uring.h | 1 |
2 files changed, 89 insertions, 3 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 84efb8956734..b3333fec349a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -222,6 +222,8 @@ struct io_ring_ctx { unsigned sq_mask; unsigned sq_thread_idle; struct io_uring_sqe *sq_sqes; + + struct list_head defer_list; } ____cacheline_aligned_in_smp; /* IO offload */ @@ -327,8 +329,11 @@ struct io_kiocb { #define REQ_F_FIXED_FILE 4 /* ctx owns file */ #define REQ_F_SEQ_PREV 8 /* sequential with previous */ #define REQ_F_PREPPED 16 /* prep already done */ +#define REQ_F_IO_DRAIN 32 /* drain existing IO first */ +#define REQ_F_IO_DRAINED 64 /* drain done */ u64 user_data; - u64 error; + u32 error; + u32 sequence; struct work_struct work; }; @@ -356,6 +361,8 @@ struct io_submit_state { unsigned int ios_left; }; +static void io_sq_wq_submit_work(struct work_struct *work); + static struct kmem_cache *req_cachep; static const struct file_operations io_uring_fops; @@ -407,10 +414,36 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) spin_lock_init(&ctx->completion_lock); INIT_LIST_HEAD(&ctx->poll_list); INIT_LIST_HEAD(&ctx->cancel_list); + INIT_LIST_HEAD(&ctx->defer_list); return ctx; } -static void io_commit_cqring(struct io_ring_ctx *ctx) +static inline bool io_sequence_defer(struct io_ring_ctx *ctx, + struct io_kiocb *req) +{ + if ((req->flags & (REQ_F_IO_DRAIN|REQ_F_IO_DRAINED)) != REQ_F_IO_DRAIN) + return false; + + return req->sequence > ctx->cached_cq_tail + ctx->sq_ring->dropped; +} + +static struct io_kiocb *io_get_deferred_req(struct io_ring_ctx *ctx) +{ + struct io_kiocb *req; + + if (list_empty(&ctx->defer_list)) + return NULL; + + req = list_first_entry(&ctx->defer_list, struct io_kiocb, list); + if (!io_sequence_defer(ctx, req)) { + list_del_init(&req->list); + return req; + } + + return NULL; +} + +static void __io_commit_cqring(struct io_ring_ctx *ctx) { struct io_cq_ring *ring = ctx->cq_ring; @@ -425,6 +458,18 @@ static void io_commit_cqring(struct io_ring_ctx *ctx) } } +static void io_commit_cqring(struct io_ring_ctx *ctx) +{ + struct io_kiocb *req; + + __io_commit_cqring(ctx); + + while ((req = io_get_deferred_req(ctx)) != NULL) { + req->flags |= REQ_F_IO_DRAINED; + queue_work(ctx->sqo_wq, &req->work); + } +} + static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx) { struct io_cq_ring *ring = ctx->cq_ring; @@ -1437,6 +1482,34 @@ static int io_poll_add(struct io_kiocb *req, const struct io_uring_sqe *sqe) return ipt.error; } +static int io_req_defer(struct io_ring_ctx *ctx, struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + struct io_uring_sqe *sqe_copy; + + if (!io_sequence_defer(ctx, req) && list_empty(&ctx->defer_list)) + return 0; + + sqe_copy = kmalloc(sizeof(*sqe_copy), GFP_KERNEL); + if (!sqe_copy) + return -EAGAIN; + + spin_lock_irq(&ctx->completion_lock); + if (!io_sequence_defer(ctx, req) && list_empty(&ctx->defer_list)) { + spin_unlock_irq(&ctx->completion_lock); + kfree(sqe_copy); + return 0; + } + + memcpy(sqe_copy, sqe, sizeof(*sqe_copy)); + req->submit.sqe = sqe_copy; + + INIT_WORK(&req->work, io_sq_wq_submit_work); + list_add_tail(&req->list, &ctx->defer_list); + spin_unlock_irq(&ctx->completion_lock); + return -EIOCBQUEUED; +} + static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, const struct sqe_submit *s, bool force_nonblock) { @@ -1684,6 +1757,11 @@ static int io_req_set_file(struct io_ring_ctx *ctx, const struct sqe_submit *s, flags = READ_ONCE(s->sqe->flags); fd = READ_ONCE(s->sqe->fd); + if (flags & IOSQE_IO_DRAIN) { + req->flags |= REQ_F_IO_DRAIN; + req->sequence = ctx->cached_sq_head - 1; + } + if (!io_op_needs_file(s->sqe)) { req->file = NULL; return 0; @@ -1713,7 +1791,7 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s, int ret; /* enforce forwards compatibility on users */ - if (unlikely(s->sqe->flags & ~IOSQE_FIXED_FILE)) + if (unlikely(s->sqe->flags & ~(IOSQE_FIXED_FILE | IOSQE_IO_DRAIN))) return -EINVAL; req = io_get_req(ctx, state); @@ -1724,6 +1802,13 @@ static int io_submit_sqe(struct io_ring_ctx *ctx, struct sqe_submit *s, if (unlikely(ret)) goto out; + ret = io_req_defer(ctx, req, s->sqe); + if (ret) { + if (ret == -EIOCBQUEUED) + ret = 0; + return ret; + } + ret = __io_submit_sqe(ctx, req, s, true); if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) { struct io_uring_sqe *sqe_copy; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index e23408692118..a7a6384d0c70 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -38,6 +38,7 @@ struct io_uring_sqe { * sqe->flags */ #define IOSQE_FIXED_FILE (1U << 0) /* use fixed fileset */ +#define IOSQE_IO_DRAIN (1U << 1) /* issue after inflight IO */ /* * io_uring_setup() flags |