From 791b7f08954869d7b8ff438f3dac3cfb39778297 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Mon, 5 Jan 2009 21:50:43 -0500 Subject: [PATCH] ext4: Fix the delalloc writepages to allocate blocks at the right offset. When iterating through the pages which have mapped buffer_heads, we failed to update the b_state value. This results in allocating blocks at logical offset 0. Signed-off-by: Aneesh Kumar K.V Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org --- fs/ext4/inode.c | 56 ++++++++++++++++++++++++++++++++++--------------- 1 file changed, 39 insertions(+), 17 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index ac97348f85b5..c77a7ac753f3 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1653,35 +1653,39 @@ struct mpage_da_data { */ static int mpage_da_submit_io(struct mpage_da_data *mpd) { - struct address_space *mapping = mpd->inode->i_mapping; - int ret = 0, err, nr_pages, i; - unsigned long index, end; - struct pagevec pvec; long pages_skipped; + struct pagevec pvec; + unsigned long index, end; + int ret = 0, err, nr_pages, i; + struct inode *inode = mpd->inode; + struct address_space *mapping = inode->i_mapping; BUG_ON(mpd->next_page <= mpd->first_page); - pagevec_init(&pvec, 0); + /* + * We need to start from the first_page to the next_page - 1 + * to make sure we also write the mapped dirty buffer_heads. + * If we look at mpd->lbh.b_blocknr we would only be looking + * at the currently mapped buffer_heads. + */ index = mpd->first_page; end = mpd->next_page - 1; + pagevec_init(&pvec, 0); while (index <= end) { - /* - * We can use PAGECACHE_TAG_DIRTY lookup here because - * even though we have cleared the dirty flag on the page - * We still keep the page in the radix tree with tag - * PAGECACHE_TAG_DIRTY. See clear_page_dirty_for_io. - * The PAGECACHE_TAG_DIRTY is cleared in set_page_writeback - * which is called via the below writepage callback. - */ - nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, - PAGECACHE_TAG_DIRTY, - min(end - index, - (pgoff_t)PAGEVEC_SIZE-1) + 1); + nr_pages = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE); if (nr_pages == 0) break; for (i = 0; i < nr_pages; i++) { struct page *page = pvec.pages[i]; + index = page->index; + if (index > end) + break; + index++; + + BUG_ON(!PageLocked(page)); + BUG_ON(PageWriteback(page)); + pages_skipped = mpd->wbc->pages_skipped; err = mapping->a_ops->writepage(page, mpd->wbc); if (!err && (pages_skipped == mpd->wbc->pages_skipped)) @@ -2095,11 +2099,29 @@ static int __mpage_da_writepage(struct page *page, bh = head; do { BUG_ON(buffer_locked(bh)); + /* + * We need to try to allocate + * unmapped blocks in the same page. + * Otherwise we won't make progress + * with the page in ext4_da_writepage + */ if (buffer_dirty(bh) && (!buffer_mapped(bh) || buffer_delay(bh))) { mpage_add_bh_to_extent(mpd, logical, bh); if (mpd->io_done) return MPAGE_DA_EXTENT_TAIL; + } else if (buffer_dirty(bh) && (buffer_mapped(bh))) { + /* + * mapped dirty buffer. We need to update + * the b_state because we look at + * b_state in mpage_da_map_blocks. We don't + * update b_size because if we find an + * unmapped buffer_head later we need to + * use the b_state flag of that buffer_head. + */ + if (mpd->lbh.b_size == 0) + mpd->lbh.b_state = + bh->b_state & BH_FLAGS; } logical++; } while ((bh = bh->b_this_page) != head); -- 2.39.5