fsnotify: generalize handling of extra event flags

commit 007d1e8395eaa59b0e7ad9eb2b53a40859446a88 upstream.

FS_EVENT_ON_CHILD gets a special treatment in fsnotify() because it is
not a flag specifying an event type, but rather an extra flags that may
be reported along with another event and control the handling of the
event by the backend.

FS_ISDIR is also an "extra flag" and not an "event type" and therefore
desrves the same treatment. With inotify/dnotify backends it was never
possible to set FS_ISDIR in mark masks, so it did not matter.
With fanotify backend, mark adding code jumps through hoops to avoid
setting the FS_ISDIR in the commulative object mask.

Separate the constant ALL_FSNOTIFY_EVENTS to ALL_FSNOTIFY_FLAGS and
ALL_FSNOTIFY_EVENTS, so the latter can be used to test for specific
event types.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index f43ea1a..14b4ac5 100644 (file)
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -193,7 +193,7 @@ static int send_to_group(struct inode *to_tell,
                         struct fsnotify_iter_info *iter_info)
 {
        struct fsnotify_group *group = NULL;
-       __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
+       __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS);
        __u32 marks_mask = 0;
        __u32 marks_ignored_mask = 0;
        struct fsnotify_mark *mark;
@@ -324,8 +324,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
        struct fsnotify_iter_info iter_info = {};
        struct mount *mnt;
        int ret = 0;
-       /* global tests shouldn't care about events on child only the specific event */
-       __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
+       __u32 test_mask = (mask & ALL_FSNOTIFY_EVENTS);
 
        if (data_is == FSNOTIFY_EVENT_PATH)
                mnt = real_mount(((const struct path *)data)->mnt);
@@ -389,7 +388,7 @@ static __init int fsnotify_init(void)
 {
        int ret;
 
-       BUG_ON(hweight32(ALL_FSNOTIFY_EVENTS) != 23);
+       BUG_ON(hweight32(ALL_FSNOTIFY_BITS) != 23);
 
        ret = init_srcu_struct(&fsnotify_mark_srcu);
        if (ret)

diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index b8f4182..4599d1c 100644 (file)
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -68,15 +68,20 @@
 
 #define ALL_FSNOTIFY_PERM_EVENTS (FS_OPEN_PERM | FS_ACCESS_PERM)
 
+/* Events that can be reported to backends */
 #define ALL_FSNOTIFY_EVENTS (FS_ACCESS | FS_MODIFY | FS_ATTRIB | \
                             FS_CLOSE_WRITE | FS_CLOSE_NOWRITE | FS_OPEN | \
                             FS_MOVED_FROM | FS_MOVED_TO | FS_CREATE | \
                             FS_DELETE | FS_DELETE_SELF | FS_MOVE_SELF | \
                             FS_UNMOUNT | FS_Q_OVERFLOW | FS_IN_IGNORED | \
-                            FS_OPEN_PERM | FS_ACCESS_PERM | FS_EXCL_UNLINK | \
-                            FS_ISDIR | FS_IN_ONESHOT | FS_DN_RENAME | \
+                            FS_OPEN_PERM | FS_ACCESS_PERM | FS_DN_RENAME)
+
+/* Extra flags that may be reported with event or control handling of events */
+#define ALL_FSNOTIFY_FLAGS  (FS_EXCL_UNLINK | FS_ISDIR | FS_IN_ONESHOT | \
                             FS_DN_MULTISHOT | FS_EVENT_ON_CHILD)
 
+#define ALL_FSNOTIFY_BITS   (ALL_FSNOTIFY_EVENTS | ALL_FSNOTIFY_FLAGS)
+
 struct fsnotify_group;
 struct fsnotify_event;
 struct fsnotify_mark;