From af197f50ac53fff1241598c73ca606754a3bb808 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 28 Apr 2020 13:15:06 -0600 Subject: io_uring: enable poll retry for any file with ->read_iter / ->write_iter We can have files like eventfd where it's perfectly fine to do poll based retry on them, right now io_file_supports_async() doesn't take that into account. Pass in data direction and check the f_op instead of just always needing an async worker. Signed-off-by: Jens Axboe --- fs/io_uring.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) (limited to 'fs/io_uring.c') diff --git a/fs/io_uring.c b/fs/io_uring.c index 084dfade5cda..516a59db73ca 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2038,7 +2038,7 @@ static struct file *__io_file_get(struct io_submit_state *state, int fd) * any file. For now, just ensure that anything potentially problematic is done * inline. */ -static bool io_file_supports_async(struct file *file) +static bool io_file_supports_async(struct file *file, int rw) { umode_t mode = file_inode(file)->i_mode; @@ -2047,7 +2047,13 @@ static bool io_file_supports_async(struct file *file) if (S_ISREG(mode) && file->f_op != &io_uring_fops) return true; - return false; + if (!(file->f_mode & FMODE_NOWAIT)) + return false; + + if (rw == READ) + return file->f_op->read_iter != NULL; + + return file->f_op->write_iter != NULL; } static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, @@ -2575,7 +2581,7 @@ static int io_read(struct io_kiocb *req, bool force_nonblock) * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so * we know to async punt it even if it was opened O_NONBLOCK */ - if (force_nonblock && !io_file_supports_async(req->file)) + if (force_nonblock && !io_file_supports_async(req->file, READ)) goto copy_iov; iov_count = iov_iter_count(&iter); @@ -2666,7 +2672,7 @@ static int io_write(struct io_kiocb *req, bool force_nonblock) * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so * we know to async punt it even if it was opened O_NONBLOCK */ - if (force_nonblock && !io_file_supports_async(req->file)) + if (force_nonblock && !io_file_supports_async(req->file, WRITE)) goto copy_iov; /* file path doesn't support NOWAIT for non-direct_IO */ @@ -2760,11 +2766,11 @@ static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; } -static bool io_splice_punt(struct file *file) +static bool io_splice_punt(struct file *file, int rw) { if (get_pipe_info(file)) return false; - if (!io_file_supports_async(file)) + if (!io_file_supports_async(file, rw)) return true; return !(file->f_flags & O_NONBLOCK); } @@ -2779,7 +2785,7 @@ static int io_splice(struct io_kiocb *req, bool force_nonblock) long ret; if (force_nonblock) { - if (io_splice_punt(in) || io_splice_punt(out)) + if (io_splice_punt(in, READ) || io_splice_punt(out, WRITE)) return -EAGAIN; flags |= SPLICE_F_NONBLOCK; } -- cgit v1.2.3-59-g8ed1b