btrfs: Use newly introduced btrfs_lock_and_flush_ordered_range

There several functions which open code
btrfs_lock_and_flush_ordered_range, just replace them with a call to the
function. No functional changes.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/extent_io.c

@@ -3204,21 +3204,10 @@ static inline void contiguous_readpages(struct extent_io_tree *tree,
 					     unsigned long *bio_flags,
 					     u64 *prev_em_start)
 {
-	struct inode *inode;
-	struct btrfs_ordered_extent *ordered;
+	struct btrfs_inode *inode = BTRFS_I(pages[0]->mapping->host);
 	int index;
 
-	inode = pages[0]->mapping->host;
-	while (1) {
-		lock_extent(tree, start, end);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
-						     end - start + 1);
-		if (!ordered)
-			break;
-		unlock_extent(tree, start, end);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(tree, inode, start, end, NULL);
 
 	for (index = 0; index < nr_pages; index++) {
 		__do_readpage(tree, pages[index], btrfs_get_extent, em_cached,
@@ -3234,22 +3223,12 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
 				   unsigned long *bio_flags,
 				   unsigned int read_flags)
 {
-	struct inode *inode = page->mapping->host;
-	struct btrfs_ordered_extent *ordered;
+	struct btrfs_inode *inode = BTRFS_I(page->mapping->host);
 	u64 start = page_offset(page);
 	u64 end = start + PAGE_SIZE - 1;
 	int ret;
 
-	while (1) {
-		lock_extent(tree, start, end);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start,
-						PAGE_SIZE);
-		if (!ordered)
-			break;
-		unlock_extent(tree, start, end);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(tree, inode, start, end, NULL);
 
 	ret = __do_readpage(tree, page, get_extent, NULL, bio, mirror_num,
 			    bio_flags, read_flags, NULL);

fs/btrfs/file.c

@@ -1550,7 +1550,6 @@ static noinline int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
 {
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct btrfs_root *root = inode->root;
-	struct btrfs_ordered_extent *ordered;
 	u64 lockstart, lockend;
 	u64 num_bytes;
 	int ret;
@@ -1563,17 +1562,8 @@ static noinline int check_can_nocow(struct btrfs_inode *inode, loff_t pos,
 	lockend = round_up(pos + *write_bytes,
 			   fs_info->sectorsize) - 1;
 
-	while (1) {
-		lock_extent(&inode->io_tree, lockstart, lockend);
-		ordered = btrfs_lookup_ordered_range(inode, lockstart,
-						     lockend - lockstart + 1);
-		if (!ordered) {
-			break;
-		}
-		unlock_extent(&inode->io_tree, lockstart, lockend);
-		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
+	btrfs_lock_and_flush_ordered_range(&inode->io_tree, inode, lockstart,
+					   lockend, NULL);
 
 	num_bytes = lockend - lockstart + 1;
 	ret = can_nocow_extent(&inode->vfs_inode, lockstart, &num_bytes,

fs/btrfs/inode.c

@@ -5004,21 +5004,8 @@ int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size)
 	if (size <= hole_start)
 		return 0;
 
-	while (1) {
-		struct btrfs_ordered_extent *ordered;
-
-		lock_extent_bits(io_tree, hole_start, block_end - 1,
-				 &cached_state);
-		ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), hole_start,
-						     block_end - hole_start);
-		if (!ordered)
-			break;
-		unlock_extent_cached(io_tree, hole_start, block_end - 1,
-				     &cached_state);
-		btrfs_start_ordered_extent(inode, ordered, 1);
-		btrfs_put_ordered_extent(ordered);
-	}
-
+	btrfs_lock_and_flush_ordered_range(io_tree, BTRFS_I(inode), hole_start,
+					   block_end - 1, &cached_state);
 	cur_offset = hole_start;
 	while (1) {
 		em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, cur_offset,