diff options
| -rw-r--r-- | fs/splice.c | 106 | ||||
| -rw-r--r-- | include/linux/splice.h | 2 |
2 files changed, 64 insertions, 44 deletions
diff --git a/fs/splice.c b/fs/splice.c index 2ca7e6931ad5..e13d93531554 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -203,8 +203,6 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe, buf->len = spd->partial[page_nr].len; buf->private = spd->partial[page_nr].private; buf->ops = spd->ops; - if (spd->flags & SPLICE_F_GIFT) - buf->flags |= PIPE_BUF_FLAG_GIFT; pipe->nrbufs++; page_nr++; @@ -225,6 +223,27 @@ out: } EXPORT_SYMBOL_GPL(splice_to_pipe); +ssize_t add_to_pipe(struct pipe_inode_info *pipe, struct pipe_buffer *buf) +{ + int ret; + + if (unlikely(!pipe->readers)) { + send_sig(SIGPIPE, current, 0); + ret = -EPIPE; + } else if (pipe->nrbufs == pipe->buffers) { + ret = -EAGAIN; + } else { + int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); + pipe->bufs[newbuf] = *buf; + pipe->nrbufs++; + return buf->len; + } + buf->ops->release(pipe, buf); + buf->ops = NULL; + return ret; +} +EXPORT_SYMBOL(add_to_pipe); + void spd_release_page(struct splice_pipe_desc *spd, unsigned int i) { put_page(spd->pages[i]); @@ -1415,32 +1434,50 @@ static long do_splice(struct file *in, loff_t __user *off_in, return -EINVAL; } -static int get_iovec_page_array(struct iov_iter *from, - struct page **pages, - struct partial_page *partial, - unsigned int pipe_buffers) +static int iter_to_pipe(struct iov_iter *from, + struct pipe_inode_info *pipe, + unsigned flags) { - int buffers = 0; - while (iov_iter_count(from)) { + struct pipe_buffer buf = { + .ops = &user_page_pipe_buf_ops, + .flags = flags + }; + size_t total = 0; + int ret = 0; + bool failed = false; + + while (iov_iter_count(from) && !failed) { + struct page *pages[16]; ssize_t copied; size_t start; + int n; - copied = iov_iter_get_pages(from, pages + buffers, ~0UL, - pipe_buffers - buffers, &start); - if (copied <= 0) - return buffers ? buffers : copied; + copied = iov_iter_get_pages(from, pages, ~0UL, 16, &start); + if (copied <= 0) { + ret = copied; + break; + } - iov_iter_advance(from, copied); - while (copied) { + for (n = 0; copied; n++, start = 0) { int size = min_t(int, copied, PAGE_SIZE - start); - partial[buffers].offset = start; - partial[buffers].len = size; + if (!failed) { + buf.page = pages[n]; + buf.offset = start; + buf.len = size; + ret = add_to_pipe(pipe, &buf); + if (unlikely(ret < 0)) { + failed = true; + } else { + iov_iter_advance(from, ret); + total += ret; + } + } else { + put_page(pages[n]); + } copied -= size; - start = 0; - buffers++; } } - return buffers; + return total ? total : ret; } static int pipe_to_user(struct pipe_inode_info *pipe, struct pipe_buffer *buf, @@ -1501,17 +1538,11 @@ static long vmsplice_to_pipe(struct file *file, const struct iovec __user *uiov, struct iovec iovstack[UIO_FASTIOV]; struct iovec *iov = iovstack; struct iov_iter from; - struct page *pages[PIPE_DEF_BUFFERS]; - struct partial_page partial[PIPE_DEF_BUFFERS]; - struct splice_pipe_desc spd = { - .pages = pages, - .partial = partial, - .nr_pages_max = PIPE_DEF_BUFFERS, - .flags = flags, - .ops = &user_page_pipe_buf_ops, - .spd_release = spd_release_page, - }; long ret; + unsigned buf_flag = 0; + + if (flags & SPLICE_F_GIFT) + buf_flag = PIPE_BUF_FLAG_GIFT; pipe = get_pipe_info(file); if (!pipe) @@ -1522,26 +1553,13 @@ static long vmsplice_to_pipe(struct file *file, const struct iovec __user *uiov, if (ret < 0) return ret; - if (splice_grow_spd(pipe, &spd)) { - kfree(iov); - return -ENOMEM; - } - pipe_lock(pipe); ret = wait_for_space(pipe, flags); - if (!ret) { - spd.nr_pages = get_iovec_page_array(&from, spd.pages, - spd.partial, - spd.nr_pages_max); - if (spd.nr_pages <= 0) - ret = spd.nr_pages; - else - ret = splice_to_pipe(pipe, &spd); - } + if (!ret) + ret = iter_to_pipe(&from, pipe, buf_flag); pipe_unlock(pipe); if (ret > 0) wakeup_pipe_readers(pipe); - splice_shrink_spd(&spd); kfree(iov); return ret; } diff --git a/include/linux/splice.h b/include/linux/splice.h index da2751d3b93d..58b300f37534 100644 --- a/include/linux/splice.h +++ b/include/linux/splice.h @@ -72,6 +72,8 @@ extern ssize_t __splice_from_pipe(struct pipe_inode_info *, struct splice_desc *, splice_actor *); extern ssize_t splice_to_pipe(struct pipe_inode_info *, struct splice_pipe_desc *); +extern ssize_t add_to_pipe(struct pipe_inode_info *, + struct pipe_buffer *); extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *, splice_direct_actor *); |
