1 files changed, 14 insertions, 0 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 314041fdfa43..7503bd46819b 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -938,6 +938,20 @@ int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
 }
 EXPORT_SYMBOL(lock_extent);
 
+int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
+                    gfp_t mask)
+{
+        int err;
+        u64 failed_start;
+
+        err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1,
+                             &failed_start, mask);
+        if (err == -EEXIST)
+                return 0;
+        return 1;
+}
+EXPORT_SYMBOL(try_lock_extent);
+
 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end,
                   gfp_t mask)
 {