[PATCH] xfs_repair: Bump link count if longform_dir2_rebuild yields shortform dir

user.mail
2025-04-15T18:09:35Z

From: Eric Sandeen <sandeen@redhat.com>

If longform_dir2_rebuild() has so few entries in *hashtab that it results
in a short form directory, bump the link count manually as shortform
directories have no explicit "." entry.

Without this, repair will end with i.e.:

resetting inode 131 nlinks from 2 to 1

in this case, because it thinks this directory inode only has 1 link
discovered, and then a 2nd repair will fix it:

resetting inode 131 nlinks from 1 to 2

because shortform_dir2_entry_check() explicitly adds the extra ref when
the (newly-created)shortform directory is checked:

/*
* no '.' entry in shortform dirs, just bump up ref count by 1
* '..' was already (or will be) accounted for and checked when
* the directory is reached or will be taken care of when the
* directory is moved to orphanage.
*/
add_inode_ref(current_irec, current_ino_offset);

Avoid this by adding the extra ref if we convert from longform to
shortform.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: user.mail <sandeen@redhat.com>
---
repair/phase6.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/repair/phase6.c b/repair/phase6.c
index dbc090a5..8804278a 100644
--- a/repair/phase6.c
+++ b/repair/phase6.c
@@ -1392,6 +1392,13 @@ _("name create failed in ino %" PRIu64 " (%d)\n"), ino, error);
_("name create failed (%d) during rebuild\n"), error);
}

+ /*
+ * If we added too few entries to retain longform, add the extra
+ * ref for . as this is now a shortform directory.
+ */
+ if (ip->i_df.if_format == XFS_DINODE_FMT_LOCAL)
+ add_inode_ref(irec, ino_offset);
+
return;

out_bmap_cancel:
--
2.49.0