Merge branch 'fsnotify' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

[sfrench/cifs-2.6.git] / fs / notify / fsnotify.c

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index 0c4583b61717646e491a28d879b5762faeb8956e..81d8959b6aef9c6595509b35efaede5ef1ebf3b5 100644 (file)
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -243,6 +243,29 @@ static int send_to_group(struct inode *to_tell,
                                        file_name, cookie, iter_info);
 }
 
+static struct fsnotify_mark *fsnotify_first_mark(struct fsnotify_mark_connector **connp)
+{
+       struct fsnotify_mark_connector *conn;
+       struct hlist_node *node = NULL;
+
+       conn = srcu_dereference(*connp, &fsnotify_mark_srcu);
+       if (conn)
+               node = srcu_dereference(conn->list.first, &fsnotify_mark_srcu);
+
+       return hlist_entry_safe(node, struct fsnotify_mark, obj_list);
+}
+
+static struct fsnotify_mark *fsnotify_next_mark(struct fsnotify_mark *mark)
+{
+       struct hlist_node *node = NULL;
+
+       if (mark)
+               node = srcu_dereference(mark->obj_list.next,
+                                       &fsnotify_mark_srcu);
+
+       return hlist_entry_safe(node, struct fsnotify_mark, obj_list);
+}
+
 /*
  * This is the main call to fsnotify.  The VFS calls into hook specific functions
  * in linux/fsnotify.h.  Those functions then in turn call here.  Here will call
@@ -252,11 +275,7 @@ static int send_to_group(struct inode *to_tell,
 int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
             const unsigned char *file_name, u32 cookie)
 {
-       struct hlist_node *inode_node = NULL, *vfsmount_node = NULL;
-       struct fsnotify_mark *inode_mark = NULL, *vfsmount_mark = NULL;
-       struct fsnotify_group *inode_group, *vfsmount_group;
-       struct fsnotify_mark_connector *inode_conn, *vfsmount_conn;
-       struct fsnotify_iter_info iter_info;
+       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 */
@@ -291,26 +310,16 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 
        if ((mask & FS_MODIFY) ||
            (test_mask & to_tell->i_fsnotify_mask)) {
-               inode_conn = srcu_dereference(to_tell->i_fsnotify_marks,
-                                             &fsnotify_mark_srcu);
-               if (inode_conn)
-                       inode_node = srcu_dereference(inode_conn->list.first,
-                                                     &fsnotify_mark_srcu);
+               iter_info.inode_mark =
+                       fsnotify_first_mark(&to_tell->i_fsnotify_marks);
        }
 
        if (mnt && ((mask & FS_MODIFY) ||
                    (test_mask & mnt->mnt_fsnotify_mask))) {
-               inode_conn = srcu_dereference(to_tell->i_fsnotify_marks,
-                                             &fsnotify_mark_srcu);
-               if (inode_conn)
-                       inode_node = srcu_dereference(inode_conn->list.first,
-                                                     &fsnotify_mark_srcu);
-               vfsmount_conn = srcu_dereference(mnt->mnt_fsnotify_marks,
-                                                &fsnotify_mark_srcu);
-               if (vfsmount_conn)
-                       vfsmount_node = srcu_dereference(
-                                               vfsmount_conn->list.first,
-                                               &fsnotify_mark_srcu);
+               iter_info.inode_mark =
+                       fsnotify_first_mark(&to_tell->i_fsnotify_marks);
+               iter_info.vfsmount_mark =
+                       fsnotify_first_mark(&mnt->mnt_fsnotify_marks);
        }
 
        /*
@@ -318,39 +327,19 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
         * ignore masks are properly reflected for mount mark notifications.
         * That's why this traversal is so complicated...
         */
-       while (inode_node || vfsmount_node) {
-               inode_group = NULL;
-               inode_mark = NULL;
-               vfsmount_group = NULL;
-               vfsmount_mark = NULL;
-
-               if (inode_node) {
-                       inode_mark = hlist_entry(srcu_dereference(inode_node, &fsnotify_mark_srcu),
-                                                struct fsnotify_mark, obj_list);
-                       inode_group = inode_mark->group;
-               }
-
-               if (vfsmount_node) {
-                       vfsmount_mark = hlist_entry(srcu_dereference(vfsmount_node, &fsnotify_mark_srcu),
-                                                   struct fsnotify_mark, obj_list);
-                       vfsmount_group = vfsmount_mark->group;
-               }
-
-               if (inode_group && vfsmount_group) {
-                       int cmp = fsnotify_compare_groups(inode_group,
-                                                         vfsmount_group);
-                       if (cmp > 0) {
-                               inode_group = NULL;
+       while (iter_info.inode_mark || iter_info.vfsmount_mark) {
+               struct fsnotify_mark *inode_mark = iter_info.inode_mark;
+               struct fsnotify_mark *vfsmount_mark = iter_info.vfsmount_mark;
+
+               if (inode_mark && vfsmount_mark) {
+                       int cmp = fsnotify_compare_groups(inode_mark->group,
+                                                         vfsmount_mark->group);
+                       if (cmp > 0)
                                inode_mark = NULL;
-                       } else if (cmp < 0) {
-                               vfsmount_group = NULL;
+                       else if (cmp < 0)
                                vfsmount_mark = NULL;
-                       }
                }
 
-               iter_info.inode_mark = inode_mark;
-               iter_info.vfsmount_mark = vfsmount_mark;
-
                ret = send_to_group(to_tell, inode_mark, vfsmount_mark, mask,
                                    data, data_is, cookie, file_name,
                                    &iter_info);
@@ -358,12 +347,12 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
                if (ret && (mask & ALL_FSNOTIFY_PERM_EVENTS))
                        goto out;
 
-               if (inode_group)
-                       inode_node = srcu_dereference(inode_node->next,
-                                                     &fsnotify_mark_srcu);
-               if (vfsmount_group)
-                       vfsmount_node = srcu_dereference(vfsmount_node->next,
-                                                        &fsnotify_mark_srcu);
+               if (inode_mark)
+                       iter_info.inode_mark =
+                               fsnotify_next_mark(iter_info.inode_mark);
+               if (vfsmount_mark)
+                       iter_info.vfsmount_mark =
+                               fsnotify_next_mark(iter_info.vfsmount_mark);
        }
        ret = 0;
 out: