vfs: retire user_path_at_empty and drop empty arg from getname_flags

No users after do_readlinkat started doing the job on its own.

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://lore.kernel.org/r/20240604155257.109500-3-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/fsopen.c

@@ -448,7 +448,7 @@ SYSCALL_DEFINE5(fsconfig,
 		fallthrough;
 	case FSCONFIG_SET_PATH:
 		param.type = fs_value_is_filename;
-		param.name = getname_flags(_value, lookup_flags, NULL);
+		param.name = getname_flags(_value, lookup_flags);
 		if (IS_ERR(param.name)) {
 			ret = PTR_ERR(param.name);
 			goto out_key;

fs/namei.c

@@ -126,7 +126,7 @@
 #define EMBEDDED_NAME_MAX	(PATH_MAX - offsetof(struct filename, iname))
 
 struct filename *
-getname_flags(const char __user *filename, int flags, int *empty)
+getname_flags(const char __user *filename, int flags)
 {
 	struct filename *result;
 	char *kname;
@@ -190,8 +190,6 @@ getname_flags(const char __user *filename, int flags, int *empty)
 	atomic_set(&result->refcnt, 1);
 	/* The empty path is special. */
 	if (unlikely(!len)) {
-		if (empty)
-			*empty = 1;
 		if (!(flags & LOOKUP_EMPTY)) {
 			putname(result);
 			return ERR_PTR(-ENOENT);
@@ -209,13 +207,13 @@ getname_uflags(const char __user *filename, int uflags)
 {
 	int flags = (uflags & AT_EMPTY_PATH) ? LOOKUP_EMPTY : 0;
 
-	return getname_flags(filename, flags, NULL);
+	return getname_flags(filename, flags);
 }
 
 struct filename *
 getname(const char __user * filename)
 {
-	return getname_flags(filename, 0, NULL);
+	return getname_flags(filename, 0);
 }
 
 struct filename *
@@ -2922,16 +2920,16 @@ int path_pts(struct path *path)
 }
 #endif
 
-int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
+int user_path_at(int dfd, const char __user *name, unsigned flags,
-		 struct path *path, int *empty)
+		 struct path *path)
 {
-	struct filename *filename = getname_flags(name, flags, empty);
+	struct filename *filename = getname_flags(name, flags);
 	int ret = filename_lookup(dfd, filename, flags, path, NULL);
 
 	putname(filename);
 	return ret;
 }
-EXPORT_SYMBOL(user_path_at_empty);
+EXPORT_SYMBOL(user_path_at);
 
 int __check_sticky(struct mnt_idmap *idmap, struct inode *dir,
 		   struct inode *inode)

fs/stat.c

@@ -300,7 +300,7 @@ int vfs_fstatat(int dfd, const char __user *filename,
 			return vfs_fstat(dfd, stat);
 	}
 
-	name = getname_flags(filename, getname_statx_lookup_flags(statx_flags), NULL);
+	name = getname_flags(filename, getname_statx_lookup_flags(statx_flags));
 	ret = vfs_statx(dfd, name, statx_flags, stat, STATX_BASIC_STATS);
 	putname(name);
 
@@ -496,7 +496,7 @@ static int do_readlinkat(int dfd, const char __user *pathname,
 		return -EINVAL;
 
 retry:
-	name = getname_flags(pathname, lookup_flags, NULL);
+	name = getname_flags(pathname, lookup_flags);
 	error = filename_lookup(dfd, name, lookup_flags, &path, NULL);
 	if (unlikely(error)) {
 		putname(name);
@@ -710,7 +710,7 @@ SYSCALL_DEFINE5(statx,
 	int ret;
 	struct filename *name;
 
-	name = getname_flags(filename, getname_statx_lookup_flags(flags), NULL);
+	name = getname_flags(filename, getname_statx_lookup_flags(flags));
 	ret = do_statx(dfd, name, flags, mask, buffer);
 	putname(name);
 

include/linux/fs.h

@@ -2701,7 +2701,7 @@ static inline struct file *file_clone_open(struct file *file)
 }
 extern int filp_close(struct file *, fl_owner_t id);
 
-extern struct filename *getname_flags(const char __user *, int, int *);
+extern struct filename *getname_flags(const char __user *, int);
 extern struct filename *getname_uflags(const char __user *, int);
 extern struct filename *getname(const char __user *);
 extern struct filename *getname_kernel(const char *);

include/linux/namei.h

@@ -50,13 +50,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
 
 extern int path_pts(struct path *path);
 
-extern int user_path_at_empty(int, const char __user *, unsigned, struct path *, int *empty);
+extern int user_path_at(int, const char __user *, unsigned, struct path *);
-
-static inline int user_path_at(int dfd, const char __user *name, unsigned flags,
-		 struct path *path)
-{
-	return user_path_at_empty(dfd, name, flags, path, NULL);
-}
 
 struct dentry *lookup_one_qstr_excl(const struct qstr *name,
 				    struct dentry *base,

io_uring/statx.c

@@ -37,8 +37,7 @@ int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 	sx->flags = READ_ONCE(sqe->statx_flags);
 
 	sx->filename = getname_flags(path,
-				     getname_statx_lookup_flags(sx->flags),
+				     getname_statx_lookup_flags(sx->flags));
-				     NULL);
 
 	if (IS_ERR(sx->filename)) {
 		int ret = PTR_ERR(sx->filename);

io_uring/xattr.c

@@ -96,7 +96,7 @@ int io_getxattr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 	path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
 
-	ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
+	ix->filename = getname_flags(path, LOOKUP_FOLLOW);
 	if (IS_ERR(ix->filename)) {
 		ret = PTR_ERR(ix->filename);
 		ix->filename = NULL;
@@ -189,7 +189,7 @@ int io_setxattr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 
 	path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
 
-	ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
+	ix->filename = getname_flags(path, LOOKUP_FOLLOW);
 	if (IS_ERR(ix->filename)) {
 		ret = PTR_ERR(ix->filename);
 		ix->filename = NULL;