namei: Standardize callers of filename_create()

filename_create() has two variants, one which drops the caller's
reference to filename (filename_create) and one which does
not (__filename_create). This can be confusing as it's unusual to drop a
caller's reference. Remove filename_create, rename __filename_create
to filename_create, and convert all callers.

Link: https://lore.kernel.org/linux-fsdevel/f6238254-35bd-7e97-5b27-21050c745874@oracle.com/
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Stephen Brennan <stephen.s.brennan@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/namei.c

@@ -3620,8 +3620,8 @@ struct file *do_file_open_root(const struct path *root,
 	return file;
 }
 
-static struct dentry *__filename_create(int dfd, struct filename *name,
-				struct path *path, unsigned int lookup_flags)
+static struct dentry *filename_create(int dfd, struct filename *name,
+				      struct path *path, unsigned int lookup_flags)
 {
 	struct dentry *dentry = ERR_PTR(-EEXIST);
 	struct qstr last;
@@ -3689,21 +3689,15 @@ static struct dentry *__filename_create(int dfd, struct filename *name,
 	return dentry;
 }
 
-static inline struct dentry *filename_create(int dfd, struct filename *name,
+struct dentry *kern_path_create(int dfd, const char *pathname,
 				struct path *path, unsigned int lookup_flags)
 {
-	struct dentry *res = __filename_create(dfd, name, path, lookup_flags);
+	struct filename *filename = getname_kernel(pathname);
+	struct dentry *res = filename_create(dfd, filename, path, lookup_flags);
 
-	putname(name);
+	putname(filename);
 	return res;
 }
-
-struct dentry *kern_path_create(int dfd, const char *pathname,
-				struct path *path, unsigned int lookup_flags)
-{
-	return filename_create(dfd, getname_kernel(pathname),
-				path, lookup_flags);
-}
 EXPORT_SYMBOL(kern_path_create);
 
 void done_path_create(struct path *path, struct dentry *dentry)
@@ -3718,7 +3712,11 @@ EXPORT_SYMBOL(done_path_create);
 inline struct dentry *user_path_create(int dfd, const char __user *pathname,
 				struct path *path, unsigned int lookup_flags)
 {
-	return filename_create(dfd, getname(pathname), path, lookup_flags);
+	struct filename *filename = getname(pathname);
+	struct dentry *res = filename_create(dfd, filename, path, lookup_flags);
+
+	putname(filename);
+	return res;
 }
 EXPORT_SYMBOL(user_path_create);
 
@@ -3799,7 +3797,7 @@ static int do_mknodat(int dfd, struct filename *name, umode_t mode,
 	if (error)
 		goto out1;
 retry:
-	dentry = __filename_create(dfd, name, &path, lookup_flags);
+	dentry = filename_create(dfd, name, &path, lookup_flags);
 	error = PTR_ERR(dentry);
 	if (IS_ERR(dentry))
 		goto out1;
@@ -3899,7 +3897,7 @@ int do_mkdirat(int dfd, struct filename *name, umode_t mode)
 	unsigned int lookup_flags = LOOKUP_DIRECTORY;
 
 retry:
-	dentry = __filename_create(dfd, name, &path, lookup_flags);
+	dentry = filename_create(dfd, name, &path, lookup_flags);
 	error = PTR_ERR(dentry);
 	if (IS_ERR(dentry))
 		goto out_putname;
@@ -4268,7 +4266,7 @@ int do_symlinkat(struct filename *from, int newdfd, struct filename *to)
 		goto out_putnames;
 	}
 retry:
-	dentry = __filename_create(newdfd, to, &path, lookup_flags);
+	dentry = filename_create(newdfd, to, &path, lookup_flags);
 	error = PTR_ERR(dentry);
 	if (IS_ERR(dentry))
 		goto out_putnames;
@@ -4432,7 +4430,7 @@ int do_linkat(int olddfd, struct filename *old, int newdfd,
 	if (error)
 		goto out_putnames;
 
-	new_dentry = __filename_create(newdfd, new, &new_path,
+	new_dentry = filename_create(newdfd, new, &new_path,
 					(how & LOOKUP_REVAL));
 	error = PTR_ERR(new_dentry);
 	if (IS_ERR(new_dentry))