path: root/fs/kernfs
diff options
authorAmir Goldstein <>2020-07-16 11:42:22 +0300
committerJan Kara <>2020-07-27 21:24:52 +0200
commit497b0c5a7c0688c1b100a9c2e267337f677c198e (patch)
tree2ed4f29d98b1a8b99ebea359b7980645a96fa6d1 /fs/kernfs
parentc8f3446c66d810e21af61cf889e7b0e3bc921b9d (diff)
fsnotify: send event to parent and child with single callback
Instead of calling fsnotify() twice, once with parent inode and once with child inode, if event should be sent to parent inode, send it with both parent and child inodes marks in object type iterator and call the backend handle_event() callback only once. The parent inode is assigned to the standard "inode" iterator type and the child inode is assigned to the special "child" iterator type. In that case, the bit FS_EVENT_ON_CHILD will be set in the event mask, the dir argument to handle_event will be the parent inode, the file_name argument to handle_event is non NULL and refers to the name of the child and the child inode can be accessed with fsnotify_data_inode(). This will allow fanotify to make decisions based on child or parent's ignored mask. For example, when a parent is interested in a specific event on its children, but a specific child wishes to ignore this event, the event will not be reported. This is not what happens with current code, but according to man page, it is the expected behavior. Link: Signed-off-by: Amir Goldstein <> Signed-off-by: Jan Kara <>
Diffstat (limited to 'fs/kernfs')
1 files changed, 6 insertions, 4 deletions
diff --git a/fs/kernfs/file.c b/fs/kernfs/file.c
index e23b3f62483c..5b1468bc509e 100644
--- a/fs/kernfs/file.c
+++ b/fs/kernfs/file.c
@@ -883,6 +883,7 @@ repeat:
list_for_each_entry(info, &kernfs_root(kn)->supers, node) {
struct kernfs_node *parent;
+ struct inode *p_inode = NULL;
struct inode *inode;
struct qstr name;
@@ -899,8 +900,6 @@ repeat:
name = (struct qstr)QSTR_INIT(kn->name, strlen(kn->name));
parent = kernfs_get_parent(kn);
if (parent) {
- struct inode *p_inode;
p_inode = ilookup(info->sb, kernfs_ino(parent));
if (p_inode) {
fsnotify(p_inode, FS_MODIFY | FS_EVENT_ON_CHILD,
@@ -911,8 +910,11 @@ repeat:
- fsnotify(inode, FS_MODIFY, inode, FSNOTIFY_EVENT_INODE,
- NULL, 0);
+ if (!p_inode) {
+ fsnotify(inode, FS_MODIFY, inode, FSNOTIFY_EVENT_INODE,
+ NULL, 0);
+ }