From 9260dc6b2ee011f728bae50edce11022567be096 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 11 Jan 2006 20:48:47 +1100 Subject: [PATCH] [XFS] various fixes for xfs_convert_page fix various bogusities in handling offets From David Chinner and Christoph Hellwig SGI-PV: 947118 SGI-Modid: xfs-linux-melb:xfs-kern:203826a Signed-off-by: Christoph Hellwig Signed-off-by: Nathan Scott --- fs/xfs/linux-2.6/xfs_aops.c | 89 ++++++++++++++++++++++--------------- 1 file changed, 52 insertions(+), 37 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c index b306e25f0f0..64c909e5c1e 100644 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ b/fs/xfs/linux-2.6/xfs_aops.c @@ -624,12 +624,13 @@ xfs_convert_page( int all_bh) { struct buffer_head *bh, *head; - unsigned long p_offset, end_offset; + xfs_off_t end_offset; + unsigned long p_offset; unsigned int type; int bbits = inode->i_blkbits; int len, page_dirty; int count = 0, done = 0, uptodate = 1; - xfs_off_t f_offset = page_offset(page); + xfs_off_t offset = page_offset(page); if (page->index != tindex) goto fail; @@ -642,21 +643,33 @@ xfs_convert_page( if (!xfs_is_delayed_page(page, (*ioendp)->io_type)) goto fail_unlock_page; - end_offset = (i_size_read(inode) & (PAGE_CACHE_SIZE - 1)); - /* * page_dirty is initially a count of buffers on the page before * EOF and is decrememted as we move each into a cleanable state. + * + * Derivation: + * + * End offset is the highest offset that this page should represent. + * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1)) + * will evaluate non-zero and be less than PAGE_CACHE_SIZE and + * hence give us the correct page_dirty count. On any other page, + * it will be zero and in that case we need page_dirty to be the + * count of buffers on the page. */ + end_offset = min_t(unsigned long long, + (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT, + i_size_read(inode)); + len = 1 << inode->i_blkbits; - end_offset = max(end_offset, PAGE_CACHE_SIZE); - end_offset = roundup(end_offset, len); - page_dirty = end_offset / len; + p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1), + PAGE_CACHE_SIZE); + p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE; + page_dirty = p_offset / len; p_offset = 0; bh = head = page_buffers(page); do { - if (p_offset >= end_offset) + if (offset >= end_offset) break; if (!buffer_uptodate(bh)) uptodate = 0; @@ -665,43 +678,45 @@ xfs_convert_page( continue; } - if (buffer_unwritten(bh)) - type = IOMAP_UNWRITTEN; - else if (buffer_delay(bh)) - type = IOMAP_DELAY; - else { - type = 0; - if (!(buffer_mapped(bh) && all_bh && startio)) { + if (buffer_unwritten(bh) || buffer_delay(bh)) { + if (buffer_unwritten(bh)) + type = IOMAP_UNWRITTEN; + else + type = IOMAP_DELAY; + + if (!xfs_iomap_valid(mp, offset)) { done = 1; - } else if (startio) { + continue; + } + + ASSERT(!(mp->iomap_flags & IOMAP_HOLE)); + ASSERT(!(mp->iomap_flags & IOMAP_DELAY)); + + xfs_map_at_offset(bh, offset, bbits, mp); + if (startio) { + xfs_add_to_ioend(inode, bh, p_offset, + type, ioendp, done); + } else { + set_buffer_dirty(bh); + unlock_buffer(bh); + mark_buffer_dirty(bh); + } + page_dirty--; + count++; + } else { + type = 0; + if (buffer_mapped(bh) && all_bh && startio) { lock_buffer(bh); xfs_add_to_ioend(inode, bh, p_offset, type, ioendp, done); count++; page_dirty--; + } else { + done = 1; } - continue; - } - - if (!xfs_iomap_valid(mp, f_offset + p_offset)) { - done = 1; - continue; - } - ASSERT(!(mp->iomap_flags & IOMAP_HOLE)); - ASSERT(!(mp->iomap_flags & IOMAP_DELAY)); - - xfs_map_at_offset(bh, f_offset + p_offset, bbits, mp); - if (startio) { - xfs_add_to_ioend(inode, bh, p_offset, - type, ioendp, done); - count++; - } else { - set_buffer_dirty(bh); - unlock_buffer(bh); - mark_buffer_dirty(bh); } - page_dirty--; - } while (p_offset += len, (bh = bh->b_this_page) != head); + } while (offset += len, p_offset += len, + (bh = bh->b_this_page) != head); if (uptodate && bh == head) SetPageUptodate(page); -- 2.32.0.93.g670b81a890