X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ftruncate.c;h=e07b1e682c38f5fca96436904eb1a9a262ce1426;hb=4522d58275f124105819723e24e912c8e5bf3cdd;hp=8fde6580657ed15c860d2f6e5bffa77c88965240;hpb=e993835441734c184d70d3716eed78a08eeb71c2;p=linux-2.6

diff --git a/mm/truncate.c b/mm/truncate.c
index 8fde658065..e07b1e682c 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -96,7 +96,6 @@ invalidate_complete_page(struct address_space *mapping, struct page *page)
 		return 0;
 
 	ret = remove_mapping(mapping, page);
-	ClearPageUptodate(page);
 
 	return ret;
 }
@@ -287,9 +286,39 @@ unsigned long invalidate_inode_pages(struct address_space *mapping)
 {
 	return invalidate_mapping_pages(mapping, 0, ~0UL);
 }
-
 EXPORT_SYMBOL(invalidate_inode_pages);
 
+/*
+ * This is like invalidate_complete_page(), except it ignores the page's
+ * refcount.  We do this because invalidate_inode_pages2() needs stronger
+ * invalidation guarantees, and cannot afford to leave pages behind because
+ * shrink_list() has a temp ref on them, or because they're transiently sitting
+ * in the lru_cache_add() pagevecs.
+ */
+static int
+invalidate_complete_page2(struct address_space *mapping, struct page *page)
+{
+	if (page->mapping != mapping)
+		return 0;
+
+	if (PagePrivate(page) && !try_to_release_page(page, GFP_KERNEL))
+		return 0;
+
+	write_lock_irq(&mapping->tree_lock);
+	if (PageDirty(page))
+		goto failed;
+
+	BUG_ON(PagePrivate(page));
+	__remove_from_page_cache(page);
+	write_unlock_irq(&mapping->tree_lock);
+	ClearPageUptodate(page);
+	page_cache_release(page);	/* pagecache ref */
+	return 1;
+failed:
+	write_unlock_irq(&mapping->tree_lock);
+	return 0;
+}
+
 /**
  * invalidate_inode_pages2_range - remove range of pages from an address_space
  * @mapping: the address_space
@@ -356,7 +385,7 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
 				}
 			}
 			was_dirty = test_clear_page_dirty(page);
-			if (!invalidate_complete_page(mapping, page)) {
+			if (!invalidate_complete_page2(mapping, page)) {
 				if (was_dirty)
 					set_page_dirty(page);
 				ret = -EIO;
@@ -366,6 +395,7 @@ int invalidate_inode_pages2_range(struct address_space *mapping,
 		pagevec_release(&pvec);
 		cond_resched();
 	}
+	WARN_ON_ONCE(ret);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(invalidate_inode_pages2_range);