xfs: hoist xfs_{bump,drop}link to libxfs

Move xfs_bumplink and xfs_droplink to libxfs.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

1 files changed, 53 insertions, 0 deletions

diff --git a/fs/xfs/libxfs/xfs_inode_util.c b/fs/xfs/libxfs/xfs_inode_util.c
index 5739871ac370..214976ecefd7 100644
--- a/fs/xfs/libxfs/xfs_inode_util.c
+++ b/fs/xfs/libxfs/xfs_inode_util.c
@@ -626,3 +626,56 @@ xfs_iunlink_remove(
 
 	return xfs_iunlink_remove_inode(tp, pag, agibp, ip);
 }
+
+/*
+ * Decrement the link count on an inode & log the change.  If this causes the
+ * link count to go to zero, move the inode to AGI unlinked list so that it can
+ * be freed when the last active reference goes away via xfs_inactive().
+ */
+int
+xfs_droplink(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip)
+{
+	struct inode		*inode = VFS_I(ip);
+
+	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
+
+	if (inode->i_nlink == 0) {
+		xfs_info_ratelimited(tp->t_mountp,
+ "Inode 0x%llx link count dropped below zero.  Pinning link count.",
+				ip->i_ino);
+		set_nlink(inode, XFS_NLINK_PINNED);
+	}
+	if (inode->i_nlink != XFS_NLINK_PINNED)
+		drop_nlink(inode);
+
+	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+
+	if (inode->i_nlink)
+		return 0;
+
+	return xfs_iunlink(tp, ip);
+}
+
+/*
+ * Increment the link count on an inode & log the change.
+ */
+void
+xfs_bumplink(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip)
+{
+	struct inode		*inode = VFS_I(ip);
+
+	xfs_trans_ichgtime(tp, ip, XFS_ICHGTIME_CHG);
+
+	if (inode->i_nlink == XFS_NLINK_PINNED - 1)
+		xfs_info_ratelimited(tp->t_mountp,
+ "Inode 0x%llx link count exceeded maximum.  Pinning link count.",
+				ip->i_ino);
+	if (inode->i_nlink != XFS_NLINK_PINNED)
+		inc_nlink(inode);
+
+	xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+}