diff options
| -rw-r--r-- | fs/mpage.c | 54 |
1 files changed, 30 insertions, 24 deletions
diff --git a/fs/mpage.c b/fs/mpage.c index 4979ffa60aaa..4cc9c5d079f7 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -439,6 +439,35 @@ struct mpage_data { unsigned use_writepage; }; +/* + * We have our BIO, so we can now mark the buffers clean. Make + * sure to only clean buffers which we know we'll be writing. + */ +static void clean_buffers(struct page *page, unsigned first_unmapped) +{ + unsigned buffer_counter = 0; + struct buffer_head *bh, *head; + if (!page_has_buffers(page)) + return; + head = page_buffers(page); + bh = head; + + do { + if (buffer_counter++ == first_unmapped) + break; + clear_buffer_dirty(bh); + bh = bh->b_this_page; + } while (bh != head); + + /* + * we cannot drop the bh if the page is not uptodate or a concurrent + * readpage would fail to serialize with the bh and it would read from + * disk before we reach the platter. + */ + if (buffer_heads_over_limit && PageUptodate(page)) + try_to_free_buffers(page); +} + static int __mpage_writepage(struct page *page, struct writeback_control *wbc, void *data) { @@ -591,30 +620,7 @@ alloc_new: goto alloc_new; } - /* - * OK, we have our BIO, so we can now mark the buffers clean. Make - * sure to only clean buffers which we know we'll be writing. - */ - if (page_has_buffers(page)) { - struct buffer_head *head = page_buffers(page); - struct buffer_head *bh = head; - unsigned buffer_counter = 0; - - do { - if (buffer_counter++ == first_unmapped) - break; - clear_buffer_dirty(bh); - bh = bh->b_this_page; - } while (bh != head); - - /* - * we cannot drop the bh if the page is not uptodate - * or a concurrent readpage would fail to serialize with the bh - * and it would read from disk before we reach the platter. - */ - if (buffer_heads_over_limit && PageUptodate(page)) - try_to_free_buffers(page); - } + clean_buffers(page, first_unmapped); BUG_ON(PageWriteback(page)); set_page_writeback(page); |