nilfs2: do not propagate ENOENT error from sufile during recovery

nilfs_sufile_free() returns the error code -ENOENT when the block where
the segment usage should be placed does not exist (hole block case), but
this error should not be propagated upwards to the mount system call.

In nilfs_prepare_segment_for_recovery(), one of the recovery steps during
mount, nilfs_sufile_free() is used and may return -ENOENT as is, so in
that case return -EINVAL instead.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ryusuke Konishi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: konis

fs/nilfs2/recovery.c

@@ -433,8 +433,17 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
 	 * The next segment is invalidated by this recovery.
 	 */
 	err = nilfs_sufile_free(sufile, segnum[1]);
-	if (unlikely(err))
+	if (unlikely(err)) {
+		if (err == -ENOENT) {
+			nilfs_err(sb,
+				  "checkpoint log inconsistency at block %llu (segment %llu): next segment %llu is unallocated",
+				  (unsigned long long)nilfs->ns_last_pseg,
+				  (unsigned long long)nilfs->ns_segnum,
+				  (unsigned long long)segnum[1]);
+			err = -EINVAL;
+		}
 		goto failed;
+	}
 
 	for (i = 1; i < 4; i++) {
 		err = nilfs_segment_list_add(head, segnum[i]);