fs: consolidate duplicate dt_type helpers

There are three copies of the same dt_type helper sprinkled around the
tree. Convert them to use the common fs_umode_to_dtype function instead,
which has the added advantage of properly returning DT_UNKNOWN when
given a mode that contains an unrecognized type.

Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Suggested-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Message-Id: <20230330104144.75547-1-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/configfs/dir.c

@@ -1599,12 +1599,6 @@ static int configfs_dir_close(struct inode *inode, struct file *file)
 	return 0;
 }
 
-/* Relationship between s_mode and the DT_xxx types */
-static inline unsigned char dt_type(struct configfs_dirent *sd)
-{
-	return (sd->s_mode >> 12) & 15;
-}
-
 static int configfs_readdir(struct file *file, struct dir_context *ctx)
 {
 	struct dentry *dentry = file->f_path.dentry;
@@ -1654,7 +1648,8 @@ static int configfs_readdir(struct file *file, struct dir_context *ctx)
 		name = configfs_get_name(next);
 		len = strlen(name);
 
-		if (!dir_emit(ctx, name, len, ino, dt_type(next)))
+		if (!dir_emit(ctx, name, len, ino,
+			      fs_umode_to_dtype(next->s_mode)))
 			return 0;
 
 		spin_lock(&configfs_dirent_lock);

fs/kernfs/dir.c

@@ -1748,12 +1748,6 @@ int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
 	return error;
 }
 
-/* Relationship between mode and the DT_xxx types */
-static inline unsigned char dt_type(struct kernfs_node *kn)
-{
-	return (kn->mode >> 12) & 15;
-}
-
 static int kernfs_dir_fop_release(struct inode *inode, struct file *filp)
 {
 	kernfs_put(filp->private_data);
@@ -1831,7 +1825,7 @@ static int kernfs_fop_readdir(struct file *file, struct dir_context *ctx)
 	     pos;
 	     pos = kernfs_dir_next_pos(ns, parent, ctx->pos, pos)) {
 		const char *name = pos->name;
-		unsigned int type = dt_type(pos);
+		unsigned int type = fs_umode_to_dtype(pos->mode);
 		int len = strlen(name);
 		ino_t ino = kernfs_ino(pos);
 

fs/libfs.c

@@ -174,12 +174,6 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence)
 }
 EXPORT_SYMBOL(dcache_dir_lseek);
 
-/* Relationship between i_mode and the DT_xxx types */
-static inline unsigned char dt_type(struct inode *inode)
-{
-	return (inode->i_mode >> 12) & 15;
-}
-
 /*
  * Directory is locked and all positive dentries in it are safe, since
  * for ramfs-type trees they can't go away without unlink() or rmdir(),
@@ -206,7 +200,8 @@ int dcache_readdir(struct file *file, struct dir_context *ctx)
 
 	while ((next = scan_positives(cursor, p, 1, next)) != NULL) {
 		if (!dir_emit(ctx, next->d_name.name, next->d_name.len,
-			      d_inode(next)->i_ino, dt_type(d_inode(next))))
+			      d_inode(next)->i_ino,
+			      fs_umode_to_dtype(d_inode(next)->i_mode)))
 			break;
 		ctx->pos++;
 		p = &next->d_child;