diff options
| -rw-r--r-- | fs/splice.c | 43 |
1 files changed, 37 insertions, 6 deletions
diff --git a/fs/splice.c b/fs/splice.c index 8d57e89924a..7e858557472 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -145,8 +145,8 @@ static struct pipe_buf_operations page_cache_pipe_buf_ops = { * pipe buffer operations. Otherwise very similar to the regular pipe_writev(). */ static ssize_t move_to_pipe(struct pipe_inode_info *pipe, struct page **pages, - int nr_pages, unsigned long offset, - unsigned long len, unsigned int flags) + int nr_pages, unsigned long len, + unsigned int offset, unsigned int flags) { int ret, do_wakeup, i; @@ -243,14 +243,16 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, unsigned int flags) { struct address_space *mapping = in->f_mapping; - unsigned int offset, nr_pages; + unsigned int loff, offset, nr_pages; struct page *pages[PIPE_BUFFERS]; struct page *page; - pgoff_t index; + pgoff_t index, end_index; + loff_t isize; + size_t bytes; int i, error; index = *ppos >> PAGE_CACHE_SHIFT; - offset = *ppos & ~PAGE_CACHE_MASK; + loff = offset = *ppos & ~PAGE_CACHE_MASK; nr_pages = (len + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; if (nr_pages > PIPE_BUFFERS) @@ -268,6 +270,7 @@ __generic_file_splice_read(struct file *in, loff_t *ppos, * Now fill in the holes: */ error = 0; + bytes = 0; for (i = 0; i < nr_pages; i++, index++) { find_page: /* @@ -336,13 +339,41 @@ readpage: goto find_page; break; } + + /* + * i_size must be checked after ->readpage(). + */ + isize = i_size_read(mapping->host); + end_index = (isize - 1) >> PAGE_CACHE_SHIFT; + if (unlikely(!isize || index > end_index)) { + page_cache_release(page); + break; + } + + /* + * if this is the last page, see if we need to shrink + * the length and stop + */ + if (end_index == index) { + loff = PAGE_CACHE_SIZE - (isize & ~PAGE_CACHE_MASK); + if (bytes + loff > isize) { + page_cache_release(page); + break; + } + /* + * force quit after adding this page + */ + nr_pages = i; + } } fill_it: pages[i] = page; + bytes += PAGE_CACHE_SIZE - loff; + loff = 0; } if (i) - return move_to_pipe(pipe, pages, i, offset, len, flags); + return move_to_pipe(pipe, pages, i, bytes, offset, flags); return error; } |