[PATCH 3/4] libxfs: port the bumplink function from the kernel

Darrick J. Wong
2023-12-31T22:36:11Z

Port the xfs_bumplink function from the kernel and use it to replace raw
calls to inc_nlink. The next patch will need this common function to
prevent integer overflows in the link count.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
include/xfs_inode.h | 2 ++
libxfs/util.c | 17 +++++++++++++++++
mkfs/proto.c | 4 ++--
repair/phase6.c | 10 +++++-----
4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/include/xfs_inode.h b/include/xfs_inode.h
index 302df4c6f7e..47959314811 100644
--- a/include/xfs_inode.h
+++ b/include/xfs_inode.h
@@ -348,6 +348,8 @@ extern void libxfs_trans_ichgtime(struct xfs_trans *,
struct xfs_inode *, int);
extern int libxfs_iflush_int (struct xfs_inode *, struct xfs_buf *);

+void libxfs_bumplink(struct xfs_trans *tp, struct xfs_inode *ip);
+
/* Inode Cache Interfaces */
extern int libxfs_iget(struct xfs_mount *, struct xfs_trans *, xfs_ino_t,
uint, struct xfs_inode **);
diff --git a/libxfs/util.c b/libxfs/util.c
index c1ddaf92c8a..11978529ed6 100644
--- a/libxfs/util.c
+++ b/libxfs/util.c
@@ -240,6 +240,23 @@ xfs_inode_propagate_flags(
ip->i_diflags |= di_flags;
}

+/*
+ * Increment the link count on an inode & log the change.
+ */
+void
+libxfs_bumplink(
+ struct xfs_trans *tp,
+ struct xfs_inode *ip)
+{
+ struct inode *inode = VFS_I(ip);
+
+ xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
+
+ inc_nlink(inode);
+
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+}
+
/*
* Initialise a newly allocated inode and return the in-core inode to the
* caller locked exclusively.
diff --git a/mkfs/proto.c b/mkfs/proto.c
index 0f2facbc32e..457899ac178 100644
--- a/mkfs/proto.c
+++ b/mkfs/proto.c
@@ -590,7 +590,7 @@ parseproto(
&creds, fsxp, &ip);
if (error)
fail(_("Inode allocation failed"), error);
- inc_nlink(VFS_I(ip)); /* account for . */
+ libxfs_bumplink(tp, ip); /* account for . */
if (!pip) {
pip = ip;
mp->m_sb.sb_rootino = ip->i_ino;
@@ -600,7 +600,7 @@ parseproto(
libxfs_trans_ijoin(tp, pip, 0);
xname.type = XFS_DIR3_FT_DIR;
newdirent(mp, tp, pip, &xname, ip->i_ino);
- inc_nlink(VFS_I(pip));
+ libxfs_bumplink(tp, pip);
libxfs_trans_log_inode(tp, pip, XFS_ILOG_CORE);
}
newdirectory(mp, tp, ip, pip);
diff --git a/repair/phase6.c b/repair/phase6.c
index ac037cf80ad..75391378291 100644
--- a/repair/phase6.c
+++ b/repair/phase6.c
@@ -944,7 +944,7 @@ mk_orphanage(xfs_mount_t *mp)
do_error(_("%s inode allocation failed %d\n"),
ORPHANAGE, error);
}
- inc_nlink(VFS_I(ip)); /* account for . */
+ libxfs_bumplink(tp, ip); /* account for . */
ino = ip->i_ino;

irec = find_inode_rec(mp,
@@ -996,7 +996,7 @@ mk_orphanage(xfs_mount_t *mp)
* for .. in the new directory, and update the irec copy of the
* on-disk nlink so we don't fail the link count check later.
*/
- inc_nlink(VFS_I(pip));
+ libxfs_bumplink(tp, pip);
irec = find_inode_rec(mp, XFS_INO_TO_AGNO(mp, mp->m_sb.sb_rootino),
XFS_INO_TO_AGINO(mp, mp->m_sb.sb_rootino));
add_inode_ref(irec, 0);
@@ -1090,7 +1090,7 @@ mv_orphanage(
if (irec)
add_inode_ref(irec, ino_offset);
else
- inc_nlink(VFS_I(orphanage_ip));
+ libxfs_bumplink(tp, orphanage_ip);
libxfs_trans_log_inode(tp, orphanage_ip, XFS_ILOG_CORE);

err = -libxfs_dir_createname(tp, ino_p, &xfs_name_dotdot,
@@ -1099,7 +1099,7 @@ mv_orphanage(
do_error(
_("creation of .. entry failed (%d)\n"), err);

- inc_nlink(VFS_I(ino_p));
+ libxfs_bumplink(tp, ino_p);
libxfs_trans_log_inode(tp, ino_p, XFS_ILOG_CORE);
err = -libxfs_trans_commit(tp);
if (err)
@@ -1124,7 +1124,7 @@ mv_orphanage(
if (irec)
add_inode_ref(irec, ino_offset);
else
- inc_nlink(VFS_I(orphanage_ip));
+ libxfs_bumplink(tp, orphanage_ip);
libxfs_trans_log_inode(tp, orphanage_ip, XFS_ILOG_CORE);

/*