1 files changed, 45 insertions, 24 deletions

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 4788c866473a..4678b416241e 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -144,14 +144,15 @@ void __fsnotify_flush_ignored_mask(struct inode *inode, void *data, int data_is)
 {
         struct fsnotify_mark *mark;
         struct hlist_node *node;
+        int idx;
+
+        idx = srcu_read_lock(&fsnotify_mark_srcu);
 
         if (!hlist_empty(&inode->i_fsnotify_marks)) {
-                spin_lock(&inode->i_lock);
-                hlist_for_each_entry(mark, node, &inode->i_fsnotify_marks, i.i_list) {
+                hlist_for_each_entry_rcu(mark, node, &inode->i_fsnotify_marks, i.i_list) {
                         if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
                                 mark->ignored_mask = 0;
                 }
-                spin_unlock(&inode->i_lock);
         }
 
         if (data_is == FSNOTIFY_EVENT_FILE) {
@@ -159,14 +160,14 @@ void __fsnotify_flush_ignored_mask(struct inode *inode, void *data, int data_is)
 
                 mnt = ((struct file *)data)->f_path.mnt;
                 if (mnt && !hlist_empty(&mnt->mnt_fsnotify_marks)) {
-                        spin_lock(&mnt->mnt_root->d_lock);
-                        hlist_for_each_entry(mark, node, &mnt->mnt_fsnotify_marks, m.m_list) {
+                        hlist_for_each_entry_rcu(mark, node, &mnt->mnt_fsnotify_marks, m.m_list) {
                                 if (!(mark->flags & FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY))
                                         mark->ignored_mask = 0;
                         }
-                        spin_unlock(&mnt->mnt_root->d_lock);
                 }
         }
+
+        srcu_read_unlock(&fsnotify_mark_srcu, idx);
 }
 
 static int send_to_group(struct fsnotify_group *group, struct inode *to_tell,
@@ -208,8 +209,10 @@ static bool needed_by_vfsmount(__u32 test_mask, struct vfsmount *mnt)
 int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
              const unsigned char *file_name, u32 cookie)
 {
+        struct fsnotify_mark *mark;
         struct fsnotify_group *group;
         struct fsnotify_event *event = NULL;
+        struct hlist_node *node;
         struct vfsmount *mnt = NULL;
         int idx, ret = 0;
         /* global tests shouldn't care about events on child only the specific event */
@@ -237,35 +240,47 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
             !needed_by_vfsmount(test_mask, mnt))
                 return 0;
 
-        /*
-         * SRCU!!  the groups list is very very much read only and the path is
-         * very hot.  The VAST majority of events are not going to need to do
-         * anything other than walk the list so it's crazy to pre-allocate.
-         */
-        idx = srcu_read_lock(&fsnotify_grp_srcu);
+        idx = srcu_read_lock(&fsnotify_mark_srcu);
 
         if (test_mask & to_tell->i_fsnotify_mask) {
-                list_for_each_entry_rcu(group, &fsnotify_inode_groups, inode_group_list) {
-                        if (test_mask & group->mask) {
-                                ret = send_to_group(group, to_tell, NULL, mask, data, data_is,
-                                                    cookie, file_name, &event);
+                hlist_for_each_entry_rcu(mark, node, &to_tell->i_fsnotify_marks, i.i_list) {
+
+                        pr_debug("%s: inode_loop: mark=%p mark->mask=%x mark->ignored_mask=%x\n",
+                                 __func__, mark, mark->mask, mark->ignored_mask);
+
+                        if (test_mask & mark->mask & ~mark->ignored_mask) {
+                                group = mark->group;
+                                if (!group)
+                                        continue;
+                                ret = send_to_group(group, to_tell, NULL, mask,
+                                                    data, data_is, cookie, file_name,
+                                                    &event);
                                 if (ret)
                                         goto out;
                         }
                 }
         }
-        if (needed_by_vfsmount(test_mask, mnt)) {
-                list_for_each_entry_rcu(group, &fsnotify_vfsmount_groups, vfsmount_group_list) {
-                        if (test_mask & group->mask) {
-                                ret = send_to_group(group, to_tell, mnt, mask, data, data_is,
-                                                    cookie, file_name, &event);
+
+        if (mnt && (test_mask & mnt->mnt_fsnotify_mask)) {
+                hlist_for_each_entry_rcu(mark, node, &mnt->mnt_fsnotify_marks, m.m_list) {
+
+                        pr_debug("%s: mnt_loop: mark=%p mark->mask=%x mark->ignored_mask=%x\n",
+                                 __func__, mark, mark->mask, mark->ignored_mask);
+
+                        if (test_mask & mark->mask & ~mark->ignored_mask)  {
+                                group = mark->group;
+                                if (!group)
+                                        continue;
+                                ret = send_to_group(group, to_tell, mnt, mask,
+                                                    data, data_is, cookie, file_name,
+                                                    &event);
                                 if (ret)
                                         goto out;
                         }
                 }
         }
 out:
-        srcu_read_unlock(&fsnotify_grp_srcu, idx);
+        srcu_read_unlock(&fsnotify_mark_srcu, idx);
         /*
          * fsnotify_create_event() took a reference so the event can't be cleaned
          * up while we are still trying to add it to lists, drop that one.
@@ -279,8 +294,14 @@ EXPORT_SYMBOL_GPL(fsnotify);
 
 static __init int fsnotify_init(void)
 {
+        int ret;
+
         BUG_ON(hweight32(ALL_FSNOTIFY_EVENTS) != 23);
 
-        return init_srcu_struct(&fsnotify_grp_srcu);
+        ret = init_srcu_struct(&fsnotify_mark_srcu);
+        if (ret)
+                panic("initializing fsnotify_mark_srcu");
+
+        return 0;
 }
-subsys_initcall(fsnotify_init);
+core_initcall(fsnotify_init);