[PATCH 12/39] convert mqueue

[Al Viro]

All modifications via normal VFS codepaths; just take care of making
persistent in in mqueue_create_attr() and discardable in mqueue_unlink()
and it doesn't need kill_litter_super() at all.

mqueue_unlink() side is best handled by having it call simple_unlink()
rather than duplicating its guts...

Signed-off-by: Al Viro <viro at zeniv.linux.org.uk>
---
 ipc/mqueue.c | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 093551fe66a7..5737130137bf 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -599,8 +599,7 @@ static int mqueue_create_attr(struct dentry *dentry, umode_t mode, void *arg)
 	dir->i_size += DIRENT_SIZE;
 	simple_inode_init_ts(dir);
 
-	d_instantiate(dentry, inode);
-	dget(dentry);
+	d_make_persistent(dentry, inode);
 	return 0;
 out_unlock:
 	spin_unlock(&mq_lock);
@@ -617,13 +616,8 @@ static int mqueue_create(struct mnt_idmap *idmap, struct inode *dir,
 
 static int mqueue_unlink(struct inode *dir, struct dentry *dentry)
 {
-	struct inode *inode = d_inode(dentry);
-
-	simple_inode_init_ts(dir);
 	dir->i_size -= DIRENT_SIZE;
-	drop_nlink(inode);
-	dput(dentry);
-	return 0;
+	return simple_unlink(dir, dentry);
 }
 
 /*
@@ -1638,7 +1632,7 @@ static const struct fs_context_operations mqueue_fs_context_ops = {
 static struct file_system_type mqueue_fs_type = {
 	.name			= "mqueue",
 	.init_fs_context	= mqueue_init_fs_context,
-	.kill_sb		= kill_litter_super,
+	.kill_sb		= kill_anon_super,
 	.fs_flags		= FS_USERNS_MOUNT,
 };
 
-- 
2.47.3