ide/ppc/pmac.c: add MODULE_LICENSE

[sfrench/cifs-2.6.git] / fs / inotify.c

diff --git a/fs/inotify.c b/fs/inotify.c
index 2c5b921528760b9da6d8abcc3f90668a8e9381d7..690e72595e6e6048addba645cf179cb418208f50 100644 (file)
--- a/fs/inotify.c
+++ b/fs/inotify.c
@@ -168,20 +168,14 @@ static void set_dentry_child_flags(struct inode *inode, int watched)
                struct dentry *child;
 
                list_for_each_entry(child, &alias->d_subdirs, d_u.d_child) {
-                       if (!child->d_inode) {
-                               WARN_ON(child->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
+                       if (!child->d_inode)
                                continue;
-                       }
+
                        spin_lock(&child->d_lock);
-                       if (watched) {
-                               WARN_ON(child->d_flags &
-                                               DCACHE_INOTIFY_PARENT_WATCHED);
+                       if (watched)
                                child->d_flags |= DCACHE_INOTIFY_PARENT_WATCHED;
-                       } else {
-                               WARN_ON(!(child->d_flags &
-                                       DCACHE_INOTIFY_PARENT_WATCHED));
-                               child->d_flags&=~DCACHE_INOTIFY_PARENT_WATCHED;
-                       }
+                       else
+                               child->d_flags &=~DCACHE_INOTIFY_PARENT_WATCHED;
                        spin_unlock(&child->d_lock);
                }
        }
@@ -253,7 +247,6 @@ void inotify_d_instantiate(struct dentry *entry, struct inode *inode)
        if (!inode)
                return;
 
-       WARN_ON(entry->d_flags & DCACHE_INOTIFY_PARENT_WATCHED);
        spin_lock(&entry->d_lock);
        parent = entry->d_parent;
        if (parent->d_inode && inotify_inode_watched(parent->d_inode))
@@ -627,6 +620,7 @@ s32 inotify_add_watch(struct inotify_handle *ih, struct inotify_watch *watch,
                      struct inode *inode, u32 mask)
 {
        int ret = 0;
+       int newly_watched;
 
        /* don't allow invalid bits: we don't want flags set */
        mask &= IN_ALL_EVENTS | IN_ONESHOT;
@@ -653,12 +647,18 @@ s32 inotify_add_watch(struct inotify_handle *ih, struct inotify_watch *watch,
         */
        watch->inode = igrab(inode);
 
-       if (!inotify_inode_watched(inode))
-               set_dentry_child_flags(inode, 1);
-
        /* Add the watch to the handle's and the inode's list */
+       newly_watched = !inotify_inode_watched(inode);
        list_add(&watch->h_list, &ih->watches);
        list_add(&watch->i_list, &inode->inotify_watches);
+       /*
+        * Set child flags _after_ adding the watch, so there is no race
+        * windows where newly instantiated children could miss their parent's
+        * watched flag.
+        */
+       if (newly_watched)
+               set_dentry_child_flags(inode, 1);
+
 out:
        mutex_unlock(&ih->mutex);
        mutex_unlock(&inode->inotify_mutex);