This commit brings back functions that set/clear EXTENT_WRITEBACK bits. These are required to reliably clear PG_writeback page flag.
Signed-off-by: Chandan Rajendra <chan...@linux.vnet.ibm.com> --- fs/btrfs/extent_io.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 73 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index fd6f011..17ff01b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1293,6 +1293,20 @@ int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end, cached_state, mask); } +static int set_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, + struct extent_state **cached_state, gfp_t mask) +{ + return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, NULL, + cached_state, mask); +} + +static int clear_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end, + struct extent_state **cached_state, gfp_t mask) +{ + return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, + cached_state, mask); +} + /* * either insert or lock state struct between start and end use mask to tell * us if waiting is desired. @@ -1399,6 +1413,7 @@ static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end) page_cache_release(page); index++; } + set_extent_writeback(tree, start, end, NULL, GFP_NOFS); return 0; } @@ -1966,6 +1981,16 @@ static void check_page_locked(struct extent_io_tree *tree, struct page *page) } } +static void check_page_writeback(struct extent_io_tree *tree, struct page *page) +{ + u64 start = page_offset(page); + u64 end = start + PAGE_CACHE_SIZE - 1; + + if (!test_range_bit(tree, start, end, EXTENT_WRITEBACK, 0, NULL)) + end_page_writeback(page); +} + +/* * When IO fails, either with EIO or csum verification fails, we * try other mirrors that might have a good copy of the data. This * io_failure_record is used to record state as we go through all the @@ -2378,6 +2403,32 @@ int end_extent_writepage(struct page *page, int err, u64 start, u64 end) return 0; } +static void clear_extent_and_page_writeback(struct address_space *mapping, + struct extent_io_tree *tree, + struct btrfs_io_bio *io_bio) +{ + struct page *page; + pgoff_t index; + u64 offset, len; + + offset = io_bio->start_offset; + len = io_bio->len; + + clear_extent_writeback(tree, offset, offset + len - 1, NULL, + GFP_ATOMIC); + + index = offset >> PAGE_CACHE_SHIFT; + while (offset < io_bio->start_offset + len) { + page = find_get_page(mapping, index); + check_page_writeback(tree, page); + page_cache_release(page); + index++; + offset += page_offset(page) + PAGE_CACHE_SIZE - offset; + } + + unlock_extent(tree, io_bio->start_offset, io_bio->start_offset + len - 1); +} + /* * after a writepage IO is done, we need to: * clear the uptodate bits on error @@ -2389,6 +2440,9 @@ int end_extent_writepage(struct page *page, int err, u64 start, u64 end) */ static void end_bio_extent_writepage(struct bio *bio, int err) { + struct address_space *mapping = bio->bi_io_vec->bv_page->mapping; + struct extent_io_tree *tree = &BTRFS_I(mapping->host)->io_tree; + struct btrfs_io_bio *io_bio = btrfs_io_bio(bio); struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; u64 start; u64 end; @@ -2413,8 +2467,8 @@ static void end_bio_extent_writepage(struct bio *bio, int err) bvec->bv_offset, bvec->bv_len); } - start = page_offset(page); - end = start + bvec->bv_offset + bvec->bv_len - 1; + start = page_offset(page) + bvec->bv_offset; + end = start + bvec->bv_len - 1; if (--bvec >= bio->bi_io_vec) prefetchw(&bvec->bv_page->flags); @@ -2422,9 +2476,10 @@ static void end_bio_extent_writepage(struct bio *bio, int err) if (end_extent_writepage(page, err, start, end)) continue; - end_page_writeback(page); } while (bvec >= bio->bi_io_vec); + clear_extent_and_page_writeback(mapping, tree, io_bio); + bio_put(bio); } @@ -3151,6 +3206,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, u64 last_byte = i_size_read(inode); u64 block_start; u64 iosize; + u64 unlock_start = start; sector_t sector; struct extent_state *cached_state = NULL; struct extent_map *em; @@ -3233,6 +3289,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, /* File system has been set read-only */ if (ret) { SetPageError(page); + unlock_start = page_end + 1; goto done; } /* @@ -3268,10 +3325,14 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, goto done_unlocked; } } + + lock_extent(tree, start, page_end); + if (tree->ops && tree->ops->writepage_start_hook) { ret = tree->ops->writepage_start_hook(page, start, page_end); if (ret) { + unlock_extent(tree, start, page_end); /* Fixup worker will requeue */ if (ret == -EBUSY) wbc->pages_skipped++; @@ -3292,9 +3353,11 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, end = page_end; if (last_byte <= start) { + unlock_extent(tree, start, page_end); if (tree->ops && tree->ops->writepage_end_io_hook) tree->ops->writepage_end_io_hook(page, start, page_end, NULL, 1); + unlock_start = page_end + 1; goto done; } @@ -3302,9 +3365,11 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, while (cur <= end) { if (cur >= last_byte) { + unlock_extent(tree, unlock_start, page_end); if (tree->ops && tree->ops->writepage_end_io_hook) tree->ops->writepage_end_io_hook(page, cur, page_end, NULL, 1); + unlock_start = page_end + 1; break; } em = epd->get_extent(inode, page, pg_offset, cur, @@ -3332,6 +3397,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, */ if (compressed || block_start == EXTENT_MAP_HOLE || block_start == EXTENT_MAP_INLINE) { + unlock_extent(tree, unlock_start, cur + iosize - 1); /* * end_io notification does not happen here for * compressed extents @@ -3351,6 +3417,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, cur += iosize; pg_offset += iosize; + unlock_start = cur; continue; } /* leave this out until we have a page_mkwrite call */ @@ -3397,6 +3464,9 @@ done: set_page_writeback(page); end_page_writeback(page); } + if (unlock_start <= page_end) + unlock_extent(tree, unlock_start, page_end); + unlock_page(page); done_unlocked: -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html