fsnotify(): constify 'data'

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/notify/fsnotify.c

@@ -125,7 +125,7 @@ EXPORT_SYMBOL_GPL(__fsnotify_parent);
 static int send_to_group(struct inode *to_tell,
 			 struct fsnotify_mark *inode_mark,
 			 struct fsnotify_mark *vfsmount_mark,
-			 __u32 mask, void *data,
+			 __u32 mask, const void *data,
 			 int data_is, u32 cookie,
 			 const unsigned char *file_name)
 {
@@ -187,7 +187,7 @@ static int send_to_group(struct inode *to_tell,
  * out to all of the registered fsnotify_group.  Those groups can then use the
  * notification event in whatever means they feel necessary.
  */
-int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 	     const unsigned char *file_name, u32 cookie)
 {
 	struct hlist_node *inode_node = NULL, *vfsmount_node = NULL;
@@ -199,7 +199,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
 	__u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
 
 	if (data_is == FSNOTIFY_EVENT_PATH)
-		mnt = real_mount(((struct path *)data)->mnt);
+		mnt = real_mount(((const struct path *)data)->mnt);
 	else
 		mnt = NULL;
 

include/linux/fsnotify_backend.h

@@ -245,7 +245,7 @@ struct fsnotify_mark {
 /* called from the vfs helpers */
 
 /* main fsnotify call to send events */
-extern int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 		    const unsigned char *name, u32 cookie);
 extern int __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask);
 extern void __fsnotify_inode_delete(struct inode *inode);
@@ -357,7 +357,7 @@ extern void fsnotify_init_event(struct fsnotify_event *event,
 
 #else
 
-static inline int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 			   const unsigned char *name, u32 cookie)
 {
 	return 0;