diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 94c6d89..24de8b6 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1088,7 +1088,7 @@
 		if (!mapping)
 			return 1;
 
-		write_lock_irq(&mapping->tree_lock);
+		spin_lock_irq(&mapping->tree_lock);
 		mapping2 = page_mapping(page);
 		if (mapping2) { /* Race with truncate? */
 			BUG_ON(mapping2 != mapping);
@@ -1102,7 +1102,7 @@
 			radix_tree_tag_set(&mapping->page_tree,
 				page_index(page), PAGECACHE_TAG_DIRTY);
 		}
-		write_unlock_irq(&mapping->tree_lock);
+		spin_unlock_irq(&mapping->tree_lock);
 		if (mapping->host) {
 			/* !PageAnon && !swapper_space */
 			__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
@@ -1258,7 +1258,7 @@
 		struct backing_dev_info *bdi = mapping->backing_dev_info;
 		unsigned long flags;
 
-		write_lock_irqsave(&mapping->tree_lock, flags);
+		spin_lock_irqsave(&mapping->tree_lock, flags);
 		ret = TestClearPageWriteback(page);
 		if (ret) {
 			radix_tree_tag_clear(&mapping->page_tree,
@@ -1269,7 +1269,7 @@
 				__bdi_writeout_inc(bdi);
 			}
 		}
-		write_unlock_irqrestore(&mapping->tree_lock, flags);
+		spin_unlock_irqrestore(&mapping->tree_lock, flags);
 	} else {
 		ret = TestClearPageWriteback(page);
 	}
@@ -1287,7 +1287,7 @@
 		struct backing_dev_info *bdi = mapping->backing_dev_info;
 		unsigned long flags;
 
-		write_lock_irqsave(&mapping->tree_lock, flags);
+		spin_lock_irqsave(&mapping->tree_lock, flags);
 		ret = TestSetPageWriteback(page);
 		if (!ret) {
 			radix_tree_tag_set(&mapping->page_tree,
@@ -1300,7 +1300,7 @@
 			radix_tree_tag_clear(&mapping->page_tree,
 						page_index(page),
 						PAGECACHE_TAG_DIRTY);
-		write_unlock_irqrestore(&mapping->tree_lock, flags);
+		spin_unlock_irqrestore(&mapping->tree_lock, flags);
 	} else {
 		ret = TestSetPageWriteback(page);
 	}