[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/fs/notify/group.c b/ap/os/linux/linux-3.4.x/fs/notify/group.c
new file mode 100644
index 0000000..63fc294
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/notify/group.c
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2008 Red Hat, Inc., Eric Paris <eparis@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING. If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/srcu.h>
+#include <linux/rculist.h>
+#include <linux/wait.h>
+
+#include <linux/fsnotify_backend.h>
+#include "fsnotify.h"
+
+#include <linux/atomic.h>
+
+/*
+ * Final freeing of a group
+ */
+void fsnotify_final_destroy_group(struct fsnotify_group *group)
+{
+ /* clear the notification queue of all events */
+ fsnotify_flush_notify(group);
+
+ if (group->ops->free_group_priv)
+ group->ops->free_group_priv(group);
+
+ kfree(group);
+}
+
+/*
+ * Trying to get rid of a group. We need to first get rid of any outstanding
+ * allocations and then free the group. Remember that fsnotify_clear_marks_by_group
+ * could miss marks that are being freed by inode and those marks could still
+ * hold a reference to this group (via group->num_marks) If we get into that
+ * situtation, the fsnotify_final_destroy_group will get called when that final
+ * mark is freed.
+ */
+static void fsnotify_destroy_group(struct fsnotify_group *group)
+{
+ /* clear all inode marks for this group */
+ fsnotify_clear_marks_by_group(group);
+
+ synchronize_srcu(&fsnotify_mark_srcu);
+
+ /* past the point of no return, matches the initial value of 1 */
+ if (atomic_dec_and_test(&group->num_marks))
+ fsnotify_final_destroy_group(group);
+}
+
+/*
+ * Drop a reference to a group. Free it if it's through.
+ */
+void fsnotify_put_group(struct fsnotify_group *group)
+{
+ if (atomic_dec_and_test(&group->refcnt))
+ fsnotify_destroy_group(group);
+}
+
+/*
+ * Create a new fsnotify_group and hold a reference for the group returned.
+ */
+struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops)
+{
+ struct fsnotify_group *group;
+
+ group = kzalloc(sizeof(struct fsnotify_group), GFP_KERNEL);
+ if (!group)
+ return ERR_PTR(-ENOMEM);
+
+ /* set to 0 when there a no external references to this group */
+ atomic_set(&group->refcnt, 1);
+ /*
+ * hits 0 when there are no external references AND no marks for
+ * this group
+ */
+ atomic_set(&group->num_marks, 1);
+
+ mutex_init(&group->notification_mutex);
+ INIT_LIST_HEAD(&group->notification_list);
+ init_waitqueue_head(&group->notification_waitq);
+ group->max_events = UINT_MAX;
+
+ spin_lock_init(&group->mark_lock);
+ INIT_LIST_HEAD(&group->marks_list);
+
+ group->ops = ops;
+
+ return group;
+}