1 files changed, 95 insertions, 81 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index d247fc0eea19..3cd57825c75f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -726,14 +726,6 @@ next:
 	start = last_end + 1;
 	if (start <= end && state && !need_resched())
 		goto hit_next;
-	goto search_again;
-
-out:
-	spin_unlock(&tree->lock);
-	if (prealloc)
-		free_extent_state(prealloc);
-
-	return 0;
 
 search_again:
 	if (start > end)
@@ -742,6 +734,14 @@ search_again:
 	if (gfpflags_allow_blocking(mask))
 		cond_resched();
 	goto again;
+
+out:
+	spin_unlock(&tree->lock);
+	if (prealloc)
+		free_extent_state(prealloc);
+
+	return 0;
+
 }
 
 static void wait_on_state(struct extent_io_tree *tree,
@@ -873,8 +873,14 @@ __set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 	bits |= EXTENT_FIRST_DELALLOC;
 again:
 	if (!prealloc && gfpflags_allow_blocking(mask)) {
+		/*
+		 * Don't care for allocation failure here because we might end
+		 * up not needing the pre-allocated extent state at all, which
+		 * is the case if we only have in the tree extent states that
+		 * cover our input range and don't cover too any other range.
+		 * If we end up needing a new extent state we allocate it later.
+		 */
 		prealloc = alloc_extent_state(mask);
-		BUG_ON(!prealloc);
 	}
 
 	spin_lock(&tree->lock);
@@ -1037,7 +1043,13 @@ hit_next:
 		goto out;
 	}
 
-	goto search_again;
+search_again:
+	if (start > end)
+		goto out;
+	spin_unlock(&tree->lock);
+	if (gfpflags_allow_blocking(mask))
+		cond_resched();
+	goto again;
 
 out:
 	spin_unlock(&tree->lock);
@@ -1046,13 +1058,6 @@ out:
 
 	return err;
 
-search_again:
-	if (start > end)
-		goto out;
-	spin_unlock(&tree->lock);
-	if (gfpflags_allow_blocking(mask))
-		cond_resched();
-	goto again;
 }
 
 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
@@ -1073,17 +1078,18 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
  * @bits:	the bits to set in this range
  * @clear_bits:	the bits to clear in this range
  * @cached_state:	state that we're going to cache
- * @mask:	the allocation mask
  *
  * This will go through and set bits for the given range.  If any states exist
  * already in this range they are set with the given bit and cleared of the
  * clear_bits.  This is only meant to be used by things that are mergeable, ie
  * converting from say DELALLOC to DIRTY.  This is not meant to be used with
  * boundary bits like LOCK.
+ *
+ * All allocations are done with GFP_NOFS.
  */
 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 		       unsigned bits, unsigned clear_bits,
-		       struct extent_state **cached_state, gfp_t mask)
+		       struct extent_state **cached_state)
 {
 	struct extent_state *state;
 	struct extent_state *prealloc = NULL;
@@ -1098,7 +1104,7 @@ int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 	btrfs_debug_check_extent_io_range(tree, start, end);
 
 again:
-	if (!prealloc && gfpflags_allow_blocking(mask)) {
+	if (!prealloc) {
 		/*
 		 * Best effort, don't worry if extent state allocation fails
 		 * here for the first iteration. We might have a cached state
@@ -1106,7 +1112,7 @@ again:
 		 * extent state allocations are needed. We'll only know this
 		 * after locking the tree.
 		 */
-		prealloc = alloc_extent_state(mask);
+		prealloc = alloc_extent_state(GFP_NOFS);
 		if (!prealloc && !first_iteration)
 			return -ENOMEM;
 	}
@@ -1263,7 +1269,13 @@ hit_next:
 		goto out;
 	}
 
-	goto search_again;
+search_again:
+	if (start > end)
+		goto out;
+	spin_unlock(&tree->lock);
+	cond_resched();
+	first_iteration = false;
+	goto again;
 
 out:
 	spin_unlock(&tree->lock);
@@ -1271,21 +1283,11 @@ out:
 		free_extent_state(prealloc);
 
 	return err;
-
-search_again:
-	if (start > end)
-		goto out;
-	spin_unlock(&tree->lock);
-	if (gfpflags_allow_blocking(mask))
-		cond_resched();
-	first_iteration = false;
-	goto again;
 }
 
 /* wrappers around set/clear extent bit */
 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
-			   unsigned bits, gfp_t mask,
-			   struct extent_changeset *changeset)
+			   unsigned bits, struct extent_changeset *changeset)
 {
 	/*
 	 * We don't support EXTENT_LOCKED yet, as current changeset will
@@ -1295,7 +1297,7 @@ int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 	 */
 	BUG_ON(bits & EXTENT_LOCKED);
 
-	return __set_extent_bit(tree, start, end, bits, 0, NULL, NULL, mask,
+	return __set_extent_bit(tree, start, end, bits, 0, NULL, NULL, GFP_NOFS,
 				changeset);
 }
 
@@ -1308,8 +1310,7 @@ int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 }
 
 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
-			     unsigned bits, gfp_t mask,
-			     struct extent_changeset *changeset)
+		unsigned bits, struct extent_changeset *changeset)
 {
 	/*
 	 * Don't support EXTENT_LOCKED case, same reason as
@@ -1317,7 +1318,7 @@ int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 	 */
 	BUG_ON(bits & EXTENT_LOCKED);
 
-	return __clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask,
+	return __clear_extent_bit(tree, start, end, bits, 0, 0, NULL, GFP_NOFS,
 				  changeset);
 }
 
@@ -1975,13 +1976,13 @@ int free_io_failure(struct inode *inode, struct io_failure_record *rec)
 	set_state_failrec(failure_tree, rec->start, NULL);
 	ret = clear_extent_bits(failure_tree, rec->start,
 				rec->start + rec->len - 1,
-				EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
+				EXTENT_LOCKED | EXTENT_DIRTY);
 	if (ret)
 		err = ret;
 
 	ret = clear_extent_bits(&BTRFS_I(inode)->io_tree, rec->start,
 				rec->start + rec->len - 1,
-				EXTENT_DAMAGED, GFP_NOFS);
+				EXTENT_DAMAGED);
 	if (ret && !err)
 		err = ret;
 
@@ -2232,13 +2233,12 @@ int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
 
 		/* set the bits in the private failure tree */
 		ret = set_extent_bits(failure_tree, start, end,
-					EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
+					EXTENT_LOCKED | EXTENT_DIRTY);
 		if (ret >= 0)
 			ret = set_state_failrec(failure_tree, start, failrec);
 		/* set the bits in the inode's tree */
 		if (ret >= 0)
-			ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED,
-						GFP_NOFS);
+			ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED);
 		if (ret < 0) {
 			kfree(failrec);
 			return ret;
@@ -3200,14 +3200,10 @@ int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 	return ret;
 }
 
-static noinline void update_nr_written(struct page *page,
-				      struct writeback_control *wbc,
-				      unsigned long nr_written)
+static void update_nr_written(struct page *page, struct writeback_control *wbc,
+			      unsigned long nr_written)
 {
 	wbc->nr_to_write -= nr_written;
-	if (wbc->range_cyclic || (wbc->nr_to_write > 0 &&
-	    wbc->range_start == 0 && wbc->range_end == LLONG_MAX))
-		page->mapping->writeback_index = page->index + nr_written;
 }
 
 /*
@@ -3368,6 +3364,8 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
 
 	while (cur <= end) {
 		u64 em_end;
+		unsigned long max_nr;
+
 		if (cur >= i_size) {
 			if (tree->ops && tree->ops->writepage_end_io_hook)
 				tree->ops->writepage_end_io_hook(page, cur,
@@ -3423,32 +3421,23 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
 			continue;
 		}
 
-		if (tree->ops && tree->ops->writepage_io_hook) {
-			ret = tree->ops->writepage_io_hook(page, cur,
-						cur + iosize - 1);
-		} else {
-			ret = 0;
+		max_nr = (i_size >> PAGE_SHIFT) + 1;
+
+		set_range_writeback(tree, cur, cur + iosize - 1);
+		if (!PageWriteback(page)) {
+			btrfs_err(BTRFS_I(inode)->root->fs_info,
+				   "page %lu not writeback, cur %llu end %llu",
+			       page->index, cur, end);
 		}
-		if (ret) {
-			SetPageError(page);
-		} else {
-			unsigned long max_nr = (i_size >> PAGE_SHIFT) + 1;
 
-			set_range_writeback(tree, cur, cur + iosize - 1);
-			if (!PageWriteback(page)) {
-				btrfs_err(BTRFS_I(inode)->root->fs_info,
-					   "page %lu not writeback, cur %llu end %llu",
-				       page->index, cur, end);
-			}
+		ret = submit_extent_page(write_flags, tree, wbc, page,
+					 sector, iosize, pg_offset,
+					 bdev, &epd->bio, max_nr,
+					 end_bio_extent_writepage,
+					 0, 0, 0, false);
+		if (ret)
+			SetPageError(page);
 
-			ret = submit_extent_page(write_flags, tree, wbc, page,
-						 sector, iosize, pg_offset,
-						 bdev, &epd->bio, max_nr,
-						 end_bio_extent_writepage,
-						 0, 0, 0, false);
-			if (ret)
-				SetPageError(page);
-		}
 		cur = cur + iosize;
 		pg_offset += iosize;
 		nr++;
@@ -3920,12 +3909,13 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 	struct inode *inode = mapping->host;
 	int ret = 0;
 	int done = 0;
-	int err = 0;
 	int nr_to_write_done = 0;
 	struct pagevec pvec;
 	int nr_pages;
 	pgoff_t index;
 	pgoff_t end;		/* Inclusive */
+	pgoff_t done_index;
+	int range_whole = 0;
 	int scanned = 0;
 	int tag;
 
@@ -3948,6 +3938,8 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 	} else {
 		index = wbc->range_start >> PAGE_SHIFT;
 		end = wbc->range_end >> PAGE_SHIFT;
+		if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
+			range_whole = 1;
 		scanned = 1;
 	}
 	if (wbc->sync_mode == WB_SYNC_ALL)
@@ -3957,6 +3949,7 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
 retry:
 	if (wbc->sync_mode == WB_SYNC_ALL)
 		tag_pages_for_writeback(mapping, index, end);
+	done_index = index;
 	while (!done && !nr_to_write_done && (index <= end) &&
 	       (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
 			min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
@@ -3966,6 +3959,7 @@ retry:
 		for (i = 0; i < nr_pages; i++) {
 			struct page *page = pvec.pages[i];
 
+			done_index = page->index;
 			/*
 			 * At this point we hold neither mapping->tree_lock nor
 			 * lock on the page itself: the page may be truncated or
@@ -4007,8 +4001,20 @@ retry:
 				unlock_page(page);
 				ret = 0;
 			}
-			if (!err && ret < 0)
-				err = ret;
+			if (ret < 0) {
+				/*
+				 * done_index is set past this page,
+				 * so media errors will not choke
+				 * background writeout for the entire
+				 * file. This has consequences for
+				 * range_cyclic semantics (ie. it may
+				 * not be suitable for data integrity
+				 * writeout).
+				 */
+				done_index = page->index + 1;
+				done = 1;
+				break;
+			}
 
 			/*
 			 * the filesystem may choose to bump up nr_to_write.
@@ -4020,7 +4026,7 @@ retry:
 		pagevec_release(&pvec);
 		cond_resched();
 	}
-	if (!scanned && !done && !err) {
+	if (!scanned && !done) {
 		/*
 		 * We hit the last page and there is more work to be done: wrap
 		 * back to the start of the file
@@ -4029,8 +4035,12 @@ retry:
 		index = 0;
 		goto retry;
 	}
+
+	if (wbc->range_cyclic || (wbc->nr_to_write > 0 && range_whole))
+		mapping->writeback_index = done_index;
+
 	btrfs_add_delayed_iput(inode);
-	return err;
+	return ret;
 }
 
 static void flush_epd_write_bio(struct extent_page_data *epd)
@@ -4379,8 +4389,12 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	if (ret < 0) {
 		btrfs_free_path(path);
 		return ret;
+	} else {
+		WARN_ON(!ret);
+		if (ret == 1)
+			ret = 0;
 	}
-	WARN_ON(!ret);
+
 	path->slots[0]--;
 	btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
 	found_type = found_key.type;
@@ -4591,7 +4605,7 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
 		if (mapped)
 			spin_unlock(&page->mapping->private_lock);
 
-		/* One for when we alloced the page */
+		/* One for when we allocated the page */
 		put_page(page);
 	} while (index != 0);
 }
@@ -4822,7 +4836,7 @@ struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
 		return NULL;
 	eb->fs_info = fs_info;
 again:
-	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+	ret = radix_tree_preload(GFP_NOFS);
 	if (ret)
 		goto free_eb;
 	spin_lock(&fs_info->buffer_lock);
@@ -4923,7 +4937,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 	if (uptodate)
 		set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 again:
-	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+	ret = radix_tree_preload(GFP_NOFS);
 	if (ret)
 		goto free_eb;
 
@@ -5751,7 +5765,7 @@ int try_release_extent_buffer(struct page *page)
 	struct extent_buffer *eb;
 
 	/*
-	 * We need to make sure noboody is attaching this page to an eb right
+	 * We need to make sure nobody is attaching this page to an eb right
 	 * now.
 	 */
 	spin_lock(&page->mapping->private_lock);