From 1cb1edb2f5ba8a3e8d47ded391007c6fe3ac0ad7 Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Thu, 6 Feb 2020 21:16:09 +0300 Subject: [PATCH] io_uring: get rid of delayed mm check Fail fast if can't grab mm, so past that requests always have an mm when required. This allows us to remove req->user altogether. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- fs/io_uring.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 77f22c3da30f..1859e866c728 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -553,7 +553,6 @@ struct io_kiocb { * llist_node is only used for poll deferred completions */ struct llist_node llist_node; - bool has_user; bool in_async; bool needs_fixed_file; u8 opcode; @@ -2056,9 +2055,6 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req, return iorw->size; } - if (!req->has_user) - return -EFAULT; - #ifdef CONFIG_COMPAT if (req->ctx->compat) return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV, @@ -4446,7 +4442,6 @@ static void io_wq_submit_work(struct io_wq_work **workptr) } if (!ret) { - req->has_user = (work->flags & IO_WQ_WORK_HAS_MM) != 0; req->in_async = true; do { ret = io_issue_sqe(req, NULL, &nxt, false); @@ -4950,6 +4945,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, for (i = 0; i < nr; i++) { const struct io_uring_sqe *sqe; struct io_kiocb *req; + int err; req = io_get_req(ctx, statep); if (unlikely(!req)) { @@ -4966,20 +4962,23 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, submitted++; if (unlikely(req->opcode >= IORING_OP_LAST)) { - io_cqring_add_event(req, -EINVAL); + err = -EINVAL; +fail_req: + io_cqring_add_event(req, err); io_double_put_req(req); break; } if (io_op_defs[req->opcode].needs_mm && !*mm) { mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm); - if (!mm_fault) { - use_mm(ctx->sqo_mm); - *mm = ctx->sqo_mm; + if (unlikely(mm_fault)) { + err = -EFAULT; + goto fail_req; } + use_mm(ctx->sqo_mm); + *mm = ctx->sqo_mm; } - req->has_user = *mm != NULL; req->in_async = async; req->needs_fixed_file = async; trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data, -- GitLab