1 files changed, 38 insertions, 27 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index c7233ff1d533..43af5a61ad25 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4514,8 +4514,11 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		}
 		ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
 					      em_len, flags);
-		if (ret)
+		if (ret) {
+			if (ret == 1)
+				ret = 0;
 			goto out_free;
+		}
 	}
 out_free:
 	free_extent_map(em);
@@ -4557,36 +4560,37 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
 	do {
 		index--;
 		page = eb->pages[index];
-		if (page && mapped) {
+		if (!page)
+			continue;
+		if (mapped)
 			spin_lock(&page->mapping->private_lock);
+		/*
+		 * We do this since we'll remove the pages after we've
+		 * removed the eb from the radix tree, so we could race
+		 * and have this page now attached to the new eb.  So
+		 * only clear page_private if it's still connected to
+		 * this eb.
+		 */
+		if (PagePrivate(page) &&
+		    page->private == (unsigned long)eb) {
+			BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+			BUG_ON(PageDirty(page));
+			BUG_ON(PageWriteback(page));
 			/*
-			 * We do this since we'll remove the pages after we've
-			 * removed the eb from the radix tree, so we could race
-			 * and have this page now attached to the new eb.  So
-			 * only clear page_private if it's still connected to
-			 * this eb.
+			 * We need to make sure we haven't be attached
+			 * to a new eb.
 			 */
-			if (PagePrivate(page) &&
-			    page->private == (unsigned long)eb) {
-				BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
-				BUG_ON(PageDirty(page));
-				BUG_ON(PageWriteback(page));
-				/*
-				 * We need to make sure we haven't be attached
-				 * to a new eb.
-				 */
-				ClearPagePrivate(page);
-				set_page_private(page, 0);
-				/* One for the page private */
-				page_cache_release(page);
-			}
-			spin_unlock(&page->mapping->private_lock);
-
-		}
-		if (page) {
-			/* One for when we alloced the page */
+			ClearPagePrivate(page);
+			set_page_private(page, 0);
+			/* One for the page private */
 			page_cache_release(page);
 		}
+
+		if (mapped)
+			spin_unlock(&page->mapping->private_lock);
+
+		/* One for when we alloced the page */
+		page_cache_release(page);
 	} while (index != 0);
 }
 
@@ -4867,6 +4871,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 				mark_extent_buffer_accessed(exists, p);
 				goto free_eb;
 			}
+			exists = NULL;
 
 			/*
 			 * Do this so attach doesn't complain and we need to
@@ -4930,12 +4935,12 @@ again:
 	return eb;
 
 free_eb:
+	WARN_ON(!atomic_dec_and_test(&eb->refs));
 	for (i = 0; i < num_pages; i++) {
 		if (eb->pages[i])
 			unlock_page(eb->pages[i]);
 	}
 
-	WARN_ON(!atomic_dec_and_test(&eb->refs));
 	btrfs_release_extent_buffer(eb);
 	return exists;
 }
@@ -4968,6 +4973,12 @@ static int release_extent_buffer(struct extent_buffer *eb)
 
 		/* Should be safe to release our pages at this point */
 		btrfs_release_extent_buffer_page(eb);
+#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
+		if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))) {
+			__free_extent_buffer(eb);
+			return 1;
+		}
+#endif
 		call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
 		return 1;
 	}