From b66e65f41426ec82b92ad4d9a752802bf9e2e383 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Sat, 30 Apr 2022 12:16:40 -0600 Subject: [PATCH] io_uring: never call io_buffer_select() for a buffer re-select Callers already have room to store the addr and length information, clean it up by having the caller just assign the previously provided data. Signed-off-by: Jens Axboe --- fs/io_uring.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 0672ce0bd832..26b69ff5c4c3 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3455,9 +3455,6 @@ static void __user *io_buffer_select(struct io_kiocb *req, size_t *len, struct io_ring_ctx *ctx = req->ctx; struct io_buffer_list *bl; - if (req->flags & REQ_F_BUFFER_SELECTED) - return u64_to_user_ptr(kbuf->addr); - io_ring_submit_lock(req->ctx, issue_flags); bl = io_buffer_get_list(ctx, req->buf_index); @@ -3497,8 +3494,9 @@ static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov, buf = io_buffer_select(req, &len, issue_flags); if (IS_ERR(buf)) return PTR_ERR(buf); + req->rw.addr = (unsigned long) buf; iov[0].iov_base = buf; - iov[0].iov_len = (compat_size_t) len; + req->rw.len = iov[0].iov_len = (compat_size_t) len; return 0; } #endif @@ -3519,8 +3517,9 @@ static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov, buf = io_buffer_select(req, &len, issue_flags); if (IS_ERR(buf)) return PTR_ERR(buf); + req->rw.addr = (unsigned long) buf; iov[0].iov_base = buf; - iov[0].iov_len = len; + req->rw.len = iov[0].iov_len = len; return 0; } @@ -3528,10 +3527,8 @@ static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov, unsigned int issue_flags) { if (req->flags & REQ_F_BUFFER_SELECTED) { - struct io_buffer *kbuf = req->kbuf; - - iov[0].iov_base = u64_to_user_ptr(kbuf->addr); - iov[0].iov_len = kbuf->len; + iov[0].iov_base = u64_to_user_ptr(req->rw.addr); + iov[0].iov_len = req->rw.len; return 0; } if (req->rw.len != 1) @@ -3545,6 +3542,13 @@ static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov, return __io_iov_buffer_select(req, iov, issue_flags); } +static inline bool io_do_buffer_select(struct io_kiocb *req) +{ + if (!(req->flags & REQ_F_BUFFER_SELECT)) + return false; + return !(req->flags & REQ_F_BUFFER_SELECTED); +} + static struct iovec *__io_import_iovec(int rw, struct io_kiocb *req, struct io_rw_state *s, unsigned int issue_flags) @@ -3567,10 +3571,11 @@ static struct iovec *__io_import_iovec(int rw, struct io_kiocb *req, sqe_len = req->rw.len; if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) { - if (req->flags & REQ_F_BUFFER_SELECT) { + if (io_do_buffer_select(req)) { buf = io_buffer_select(req, &sqe_len, issue_flags); if (IS_ERR(buf)) return ERR_CAST(buf); + req->rw.addr = (unsigned long) buf; req->rw.len = sqe_len; } @@ -5555,7 +5560,7 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) (sr->flags & IORING_RECVSEND_POLL_FIRST)) return io_setup_async_msg(req, kmsg); - if (req->flags & REQ_F_BUFFER_SELECT) { + if (io_do_buffer_select(req)) { void __user *buf; buf = io_buffer_select(req, &sr->len, issue_flags); @@ -5619,7 +5624,7 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags) if (unlikely(!sock)) return -ENOTSOCK; - if (req->flags & REQ_F_BUFFER_SELECT) { + if (io_do_buffer_select(req)) { void __user *buf; buf = io_buffer_select(req, &sr->len, issue_flags); -- 2.11.0