Fixed MTP to work with TWRP

mm/list_lru.c

@@ -0,0 +1,152 @@
+/*
+ * Copyright (c) 2013 Red Hat, Inc. and Parallels Inc. All rights reserved.
+ * Authors: David Chinner and Glauber Costa
+ *
+ * Generic LRU infrastructure
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/list_lru.h>
+#include <linux/slab.h>
+
+bool list_lru_add(struct list_lru *lru, struct list_head *item)
+{
+	int nid = page_to_nid(virt_to_page(item));
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	WARN_ON_ONCE(nlru->nr_items < 0);
+	if (list_empty(item)) {
+		list_add_tail(item, &nlru->list);
+		if (nlru->nr_items++ == 0)
+			node_set(nid, lru->active_nodes);
+		spin_unlock(&nlru->lock);
+		return true;
+	}
+	spin_unlock(&nlru->lock);
+	return false;
+}
+EXPORT_SYMBOL_GPL(list_lru_add);
+
+bool list_lru_del(struct list_lru *lru, struct list_head *item)
+{
+	int nid = page_to_nid(virt_to_page(item));
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	if (!list_empty(item)) {
+		list_del_init(item);
+		if (--nlru->nr_items == 0)
+			node_clear(nid, lru->active_nodes);
+		WARN_ON_ONCE(nlru->nr_items < 0);
+		spin_unlock(&nlru->lock);
+		return true;
+	}
+	spin_unlock(&nlru->lock);
+	return false;
+}
+EXPORT_SYMBOL_GPL(list_lru_del);
+
+unsigned long
+list_lru_count_node(struct list_lru *lru, int nid)
+{
+	unsigned long count = 0;
+	struct list_lru_node *nlru = &lru->node[nid];
+
+	spin_lock(&nlru->lock);
+	WARN_ON_ONCE(nlru->nr_items < 0);
+	count += nlru->nr_items;
+	spin_unlock(&nlru->lock);
+
+	return count;
+}
+EXPORT_SYMBOL_GPL(list_lru_count_node);
+
+unsigned long
+list_lru_walk_node(struct list_lru *lru, int nid, list_lru_walk_cb isolate,
+		   void *cb_arg, unsigned long *nr_to_walk)
+{
+
+	struct list_lru_node	*nlru = &lru->node[nid];
+	struct list_head *item, *n;
+	unsigned long isolated = 0;
+
+	spin_lock(&nlru->lock);
+restart:
+	list_for_each_safe(item, n, &nlru->list) {
+		enum lru_status ret;
+
+		/*
+		 * decrement nr_to_walk first so that we don't livelock if we
+		 * get stuck on large numbesr of LRU_RETRY items
+		 */
+		if (!*nr_to_walk)
+			break;
+		--*nr_to_walk;
+
+		ret = isolate(item, &nlru->lock, cb_arg);
+		switch (ret) {
+		case LRU_REMOVED_RETRY:
+			assert_spin_locked(&nlru->lock);
+		case LRU_REMOVED:
+			if (--nlru->nr_items == 0)
+				node_clear(nid, lru->active_nodes);
+			WARN_ON_ONCE(nlru->nr_items < 0);
+			isolated++;
+			/*
+			 * If the lru lock has been dropped, our list
+			 * traversal is now invalid and so we have to
+			 * restart from scratch.
+			 */
+			if (ret == LRU_REMOVED_RETRY)
+				goto restart;
+			break;
+		case LRU_ROTATE:
+			list_move_tail(item, &nlru->list);
+			break;
+		case LRU_SKIP:
+			break;
+		case LRU_RETRY:
+			/*
+			 * The lru lock has been dropped, our list traversal is
+			 * now invalid and so we have to restart from scratch.
+			 */
+			assert_spin_locked(&nlru->lock);
+			goto restart;
+		default:
+			BUG();
+		}
+	}
+
+	spin_unlock(&nlru->lock);
+	return isolated;
+}
+EXPORT_SYMBOL_GPL(list_lru_walk_node);
+
+int list_lru_init_key(struct list_lru *lru, struct lock_class_key *key)
+{
+	int i;
+	size_t size = sizeof(*lru->node) * nr_node_ids;
+
+	lru->node = kzalloc(size, GFP_KERNEL);
+	if (!lru->node)
+		return -ENOMEM;
+
+	nodes_clear(lru->active_nodes);
+	for (i = 0; i < nr_node_ids; i++) {
+		spin_lock_init(&lru->node[i].lock);
+		if (key)
+			lockdep_set_class(&lru->node[i].lock, key);
+		INIT_LIST_HEAD(&lru->node[i].list);
+		lru->node[i].nr_items = 0;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(list_lru_init_key);
+
+void list_lru_destroy(struct list_lru *lru)
+{
+	kfree(lru->node);
+}
+EXPORT_SYMBOL_GPL(list_lru_destroy);