ocfs2: Read from an unwritten extent returns zeros

Return an optional extent flags field from our lookup functions and wire up
callers to treat unwritten regions as holes for the purpose of returning
zeros to the user.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index ea0ce41..eef6c18 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -70,9 +70,11 @@ static int ocfs2_search_extent_list(struct ocfs2_extent_list *el,
 }
 
 int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
-		       u32 *p_cluster, u32 *num_clusters)
+		       u32 *p_cluster, u32 *num_clusters,
+		       unsigned int *extent_flags)
 {
 	int ret, i;
+	unsigned int flags = 0;
 	struct buffer_head *di_bh = NULL;
 	struct buffer_head *eb_bh = NULL;
 	struct ocfs2_dinode *di;
@@ -142,8 +144,13 @@ int ocfs2_get_clusters(struct inode *inode, u32 v_cluster,
 
 		if (num_clusters)
 			*num_clusters = ocfs2_rec_clusters(el, rec) - coff;
+
+		flags = rec->e_flags;
 	}
 
+	if (extent_flags)
+		*extent_flags = flags;
+
 out:
 	brelse(di_bh);
 	brelse(eb_bh);
@@ -155,7 +162,7 @@ out:
  * all while the map is in the process of being updated.
  */
 int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
-				int *ret_count)
+				int *ret_count, unsigned int *extent_flags)
 {
 	int ret;
 	int bpc = ocfs2_clusters_to_blocks(inode->i_sb, 1);
@@ -164,7 +171,8 @@ int ocfs2_extent_map_get_blocks(struct inode *inode, u64 v_blkno, u64 *p_blkno,
 
 	cpos = ocfs2_blocks_to_clusters(inode->i_sb, v_blkno);
 
-	ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters);
+	ret = ocfs2_get_clusters(inode, cpos, &p_cluster, &num_clusters,
+				 extent_flags);
 	if (ret) {
 		mlog_errno(ret);
 		goto out;