Btrfs: Fix uninitialized root flags for subvolumes
[cascardo/linux.git] / fs / xfs / xfs_iomap.c
index 55582bd..8a0f044 100644 (file)
@@ -337,7 +337,12 @@ xfs_iomap_prealloc_size(
                int shift = 0;
                int64_t freesp;
 
-               alloc_blocks = XFS_B_TO_FSB(mp, ip->i_size);
+               /*
+                * rounddown_pow_of_two() returns an undefined result
+                * if we pass in alloc_blocks = 0. Hence the "+ 1" to
+                * ensure we always pass in a non-zero value.
+                */
+               alloc_blocks = XFS_B_TO_FSB(mp, ip->i_size) + 1;
                alloc_blocks = XFS_FILEOFF_MIN(MAXEXTLEN,
                                        rounddown_pow_of_two(alloc_blocks));