diff options
Diffstat (limited to 'fs')
-rw-r--r-- | fs/io_uring.c | 60 |
1 files changed, 54 insertions, 6 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 9d8e703bc851..ca7570aca430 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1298,6 +1298,51 @@ static void io_async_list_note(int rw, struct io_kiocb *req, size_t len) } } +/* + * For files that don't have ->read_iter() and ->write_iter(), handle them + * by looping over ->read() or ->write() manually. + */ +static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb, + struct iov_iter *iter) +{ + ssize_t ret = 0; + + /* + * Don't support polled IO through this interface, and we can't + * support non-blocking either. For the latter, this just causes + * the kiocb to be handled from an async context. + */ + if (kiocb->ki_flags & IOCB_HIPRI) + return -EOPNOTSUPP; + if (kiocb->ki_flags & IOCB_NOWAIT) + return -EAGAIN; + + while (iov_iter_count(iter)) { + struct iovec iovec = iov_iter_iovec(iter); + ssize_t nr; + + if (rw == READ) { + nr = file->f_op->read(file, iovec.iov_base, + iovec.iov_len, &kiocb->ki_pos); + } else { + nr = file->f_op->write(file, iovec.iov_base, + iovec.iov_len, &kiocb->ki_pos); + } + + if (nr < 0) { + if (!ret) + ret = nr; + break; + } + ret += nr; + if (nr != iovec.iov_len) + break; + iov_iter_advance(iter, nr); + } + + return ret; +} + static int io_read(struct io_kiocb *req, const struct sqe_submit *s, bool force_nonblock) { @@ -1315,8 +1360,6 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s, if (unlikely(!(file->f_mode & FMODE_READ))) return -EBADF; - if (unlikely(!file->f_op->read_iter)) - return -EINVAL; ret = io_import_iovec(req->ctx, READ, s, &iovec, &iter); if (ret < 0) @@ -1331,7 +1374,11 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s, if (!ret) { ssize_t ret2; - ret2 = call_read_iter(file, kiocb, &iter); + if (file->f_op->read_iter) + ret2 = call_read_iter(file, kiocb, &iter); + else + ret2 = loop_rw_iter(READ, file, kiocb, &iter); + /* * In case of a short read, punt to async. This can happen * if we have data partially cached. Alternatively we can @@ -1376,8 +1423,6 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s, file = kiocb->ki_filp; if (unlikely(!(file->f_mode & FMODE_WRITE))) return -EBADF; - if (unlikely(!file->f_op->write_iter)) - return -EINVAL; ret = io_import_iovec(req->ctx, WRITE, s, &iovec, &iter); if (ret < 0) @@ -1415,7 +1460,10 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s, } kiocb->ki_flags |= IOCB_WRITE; - ret2 = call_write_iter(file, kiocb, &iter); + if (file->f_op->write_iter) + ret2 = call_write_iter(file, kiocb, &iter); + else + ret2 = loop_rw_iter(WRITE, file, kiocb, &iter); if (!force_nonblock || ret2 != -EAGAIN) { io_rw_done(kiocb, ret2); } else { |