ext4: update extent status tree after an extent is zeroed out

When we try to split an extent, this extent could be zeroed out and mark
as initialized.  But we don't know this in ext4_map_blocks because it
only returns a length of allocated extent.  Meanwhile we will mark this
extent as uninitialized because we only check m_flags.

This commit update extent status tree when we try to split an unwritten
extent.  We don't need to worry about the status of this extent because
we always mark it as initialized.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Dmitry Monakhov <dmonakhov@openvz.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 56140ad4150b..d8e2d4dc311e 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -39,6 +39,8 @@
                                  EXTENT_STATUS_DELAYED | \
                                  EXTENT_STATUS_HOLE)
 
+struct ext4_extent;
+
 struct extent_status {
         struct rb_node rb_node;
         ext4_lblk_t es_lblk;    /* first logical block extent covers */
@@ -64,6 +66,7 @@ extern void ext4_es_find_delayed_extent(struct inode *inode, ext4_lblk_t lblk,
                                         struct extent_status *es);
 extern int ext4_es_lookup_extent(struct inode *inode, ext4_lblk_t lblk,
                                  struct extent_status *es);
+extern int ext4_es_zeroout(struct inode *inode, struct ext4_extent *ex);
 
 static inline int ext4_es_is_written(struct extent_status *es)
 {