[PATCH 16/22] xfs: create libxfs helper to link an existing inode into a directory

Darrick J. Wong
2019-01-01T02:20:59Z

Create a new libxfs function to link an existing inode into a directory.
The upcoming metadata directory feature will need this to create a
metadata directory tree.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_dir2.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_dir2.h | 3 +++
fs/xfs/xfs_inode.c | 24 +-----------------------
3 files changed, 48 insertions(+), 23 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_dir2.c b/fs/xfs/libxfs/xfs_dir2.c
index aaac55668e9d..4cd2afa234ca 100644
--- a/fs/xfs/libxfs/xfs_dir2.c
+++ b/fs/xfs/libxfs/xfs_dir2.c
@@ -748,3 +748,47 @@ xfs_dir_create_new_child(

return xfs_bumplink(tp, dp);
}
+
+/*
+ * Given a directory @dp, an existing non-directory inode @ip, and a @name,
+ * link @ip into @dp under the given @name. Both inodes must have the ILOCK
+ * held.
+ */
+int
+xfs_dir_link_existing_child(
+ struct xfs_trans *tp,
+ uint resblks,
+ struct xfs_inode *dp,
+ struct xfs_name *name,
+ struct xfs_inode *ip)
+{
+ int error;
+
+ ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+ ASSERT(xfs_isilocked(dp, XFS_ILOCK_EXCL));
+ ASSERT(!S_ISDIR(VFS_I(ip)->i_mode));
+
+ if (!resblks) {
+ error = xfs_dir_canenter(tp, dp, name);
+ if (error)
+ return error;
+ }
+
+ /*
+ * Handle initial link state of O_TMPFILE inode
+ */
+ if (VFS_I(ip)->i_nlink == 0) {
+ error = xfs_iunlink_remove(tp, ip);
+ if (error)
+ return error;
+ }
+
+ error = xfs_dir_createname(tp, dp, name, ip->i_ino, resblks);
+ if (error)
+ return error;
+
+ xfs_trans_ichgtime(tp, dp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
+ xfs_trans_log_inode(tp, dp, XFS_ILOG_CORE);
+
+ return xfs_bumplink(tp, ip);
+}
diff --git a/fs/xfs/libxfs/xfs_dir2.h b/fs/xfs/libxfs/xfs_dir2.h
index 5219ca503012..7e713fcb4c40 100644
--- a/fs/xfs/libxfs/xfs_dir2.h
+++ b/fs/xfs/libxfs/xfs_dir2.h
@@ -330,5 +330,8 @@ void *xfs_dir3_data_endp(struct xfs_da_geometry *geo,
int xfs_dir_create_new_child(struct xfs_trans *tp, uint resblks,
struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode *ip);
+int xfs_dir_link_existing_child(struct xfs_trans *tp, uint resblks,
+ struct xfs_inode *dp, struct xfs_name *name,
+ struct xfs_inode *ip);

#endif /* __XFS_DIR2_H__ */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 1469f905be36..189f11bba539 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -974,29 +974,7 @@ xfs_link(
goto error_return;
}

- if (!resblks) {
- error = xfs_dir_canenter(tp, tdp, target_name);
- if (error)
- goto error_return;
- }
-
- /*
- * Handle initial link state of O_TMPFILE inode
- */
- if (VFS_I(sip)->i_nlink == 0) {
- error = xfs_iunlink_remove(tp, sip);
- if (error)
- goto error_return;
- }
-
- error = xfs_dir_createname(tp, tdp, target_name, sip->i_ino,
- resblks);
- if (error)
- goto error_return;
- xfs_trans_ichgtime(tp, tdp, XFS_ICHGTIME_MOD | XFS_ICHGTIME_CHG);
- xfs_trans_log_inode(tp, tdp, XFS_ILOG_CORE);
-
- error = xfs_bumplink(tp, sip);
+ error = xfs_dir_link_existing_child(tp, resblks, tdp, target_name, sip);
if (error)
goto error_return;