fsnotify: create method handle_inode_event() in fsnotify_operations

The method handle_event() grew a lot of complexity due to the design of
fanotify and merging of ignore masks.

Most backends do not care about this complex functionality, so we can hide
this complexity from them.

Introduce a method handle_inode_event() that serves those backends and
passes a single inode mark and less arguments.

This change converts all backends except fanotify and inotify to use the
simplified handle_inode_event() method.  In pricipal, inotify could have
also used the new method, but that would require passing more arguments
on the simple helper (data, data_type, cookie), so we leave it with the
handle_event() method.

Link: https://lore.kernel.org/r/20200722125849.17418-9-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

3 files changed, 19 insertions, 28 deletions

diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c
index bd3a6b79316a..bfcfcd61adb6 100644
--- a/kernel/audit_fsnotify.c
+++ b/kernel/audit_fsnotify.c
@@ -152,35 +152,31 @@ static void audit_autoremove_mark_rule(struct audit_fsnotify_mark *audit_mark)
 }
 
 /* Update mark data in audit rules based on fsnotify events. */
-static int audit_mark_handle_event(struct fsnotify_group *group, u32 mask,
-				   const void *data, int data_type,
-				   struct inode *dir,
-				   const struct qstr *dname, u32 cookie,
-				   struct fsnotify_iter_info *iter_info)
+static int audit_mark_handle_event(struct fsnotify_mark *inode_mark, u32 mask,
+				   struct inode *inode, struct inode *dir,
+				   const struct qstr *dname)
 {
-	struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info);
 	struct audit_fsnotify_mark *audit_mark;
-	const struct inode *inode = fsnotify_data_inode(data, data_type);
 
 	audit_mark = container_of(inode_mark, struct audit_fsnotify_mark, mark);
 
-	BUG_ON(group != audit_fsnotify_group);
-
-	if (WARN_ON(!inode))
+	if (WARN_ON_ONCE(inode_mark->group != audit_fsnotify_group) ||
+	    WARN_ON_ONCE(!inode))
 		return 0;
 
 	if (mask & (FS_CREATE|FS_MOVED_TO|FS_DELETE|FS_MOVED_FROM)) {
 		if (audit_compare_dname_path(dname, audit_mark->path, AUDIT_NAME_FULL))
 			return 0;
 		audit_update_mark(audit_mark, inode);
-	} else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF))
+	} else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF)) {
 		audit_autoremove_mark_rule(audit_mark);
+	}
 
 	return 0;
 }
 
 static const struct fsnotify_ops audit_mark_fsnotify_ops = {
-	.handle_event =	audit_mark_handle_event,
+	.handle_inode_event = audit_mark_handle_event,
 	.free_mark = audit_fsnotify_free_mark,
 };
 
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 2ce2ac1ce100..025d24abf15d 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -1037,11 +1037,9 @@ static void evict_chunk(struct audit_chunk *chunk)
 		audit_schedule_prune();
 }
 
-static int audit_tree_handle_event(struct fsnotify_group *group, u32 mask,
-				   const void *data, int data_type,
-				   struct inode *dir,
-				   const struct qstr *file_name, u32 cookie,
-				   struct fsnotify_iter_info *iter_info)
+static int audit_tree_handle_event(struct fsnotify_mark *mark, u32 mask,
+				   struct inode *inode, struct inode *dir,
+				   const struct qstr *file_name)
 {
 	return 0;
 }
@@ -1070,7 +1068,7 @@ static void audit_tree_freeing_mark(struct fsnotify_mark *mark,
 }
 
 static const struct fsnotify_ops audit_tree_ops = {
-	.handle_event = audit_tree_handle_event,
+	.handle_inode_event = audit_tree_handle_event,
 	.freeing_mark = audit_tree_freeing_mark,
 	.free_mark = audit_tree_destroy_watch,
 };
diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c
index e23d54bcc587..246e5ba704c0 100644
--- a/kernel/audit_watch.c
+++ b/kernel/audit_watch.c
@@ -464,20 +464,17 @@ void audit_remove_watch_rule(struct audit_krule *krule)
 }
 
 /* Update watch data in audit rules based on fsnotify events. */
-static int audit_watch_handle_event(struct fsnotify_group *group, u32 mask,
-				    const void *data, int data_type,
-				    struct inode *dir,
-				    const struct qstr *dname, u32 cookie,
-				    struct fsnotify_iter_info *iter_info)
+static int audit_watch_handle_event(struct fsnotify_mark *inode_mark, u32 mask,
+				    struct inode *inode, struct inode *dir,
+				    const struct qstr *dname)
 {
-	struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info);
-	const struct inode *inode = fsnotify_data_inode(data, data_type);
 	struct audit_parent *parent;
 
 	parent = container_of(inode_mark, struct audit_parent, mark);
 
-	BUG_ON(group != audit_watch_group);
-	WARN_ON(!inode);
+	if (WARN_ON_ONCE(inode_mark->group != audit_watch_group) ||
+	    WARN_ON_ONCE(!inode))
+		return 0;
 
 	if (mask & (FS_CREATE|FS_MOVED_TO) && inode)
 		audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0);
@@ -490,7 +487,7 @@ static int audit_watch_handle_event(struct fsnotify_group *group, u32 mask,
 }
 
 static const struct fsnotify_ops audit_watch_fsnotify_ops = {
-	.handle_event = 	audit_watch_handle_event,
+	.handle_inode_event =	audit_watch_handle_event,
 	.free_mark =		audit_watch_free_mark,
 };