1 files changed, 4 insertions, 0 deletions

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index d202d765dad2..c4068f6abf03 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3644,6 +3644,10 @@ long ext4_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len)
         struct ext4_map_blocks map;
         unsigned int credits, blkbits = inode->i_blkbits;
 
+        /* We only support the FALLOC_FL_KEEP_SIZE mode */
+        if (mode && (mode != FALLOC_FL_KEEP_SIZE))
+                return -EOPNOTSUPP;
+
         /*
          * currently supporting (pre)allocate mode for extent-based
          * files _only_