export_operations->open(): constify path argument

for the method and its sole instance...

Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: Al Viro

fs/pidfs.c

@@ -847,7 +847,7 @@ static int pidfs_export_permission(struct handle_to_path_ctx *ctx,
 	return 0;
 }
 
-static struct file *pidfs_export_open(struct path *path, unsigned int oflags)
+static struct file *pidfs_export_open(const struct path *path, unsigned int oflags)
 {
 	/*
 	 * Clear O_LARGEFILE as open_by_handle_at() forces it and raise

include/linux/exportfs.h

@@ -270,7 +270,7 @@ struct export_operations {
 	int (*commit_blocks)(struct inode *inode, struct iomap *iomaps,
 			     int nr_iomaps, struct iattr *iattr);
 	int (*permission)(struct handle_to_path_ctx *ctx, unsigned int oflags);
-	struct file * (*open)(struct path *path, unsigned int oflags);
+	struct file * (*open)(const struct path *path, unsigned int oflags);
 #define	EXPORT_OP_NOWCC			(0x1) /* don't collect v3 wcc data */
 #define	EXPORT_OP_NOSUBTREECHK		(0x2) /* no subtree checking */
 #define	EXPORT_OP_CLOSE_BEFORE_UNLINK	(0x4) /* close files before unlink */