Btrfs: fix duplicate checking logic

When merging my code into the integration test the second check for duplicate
entries got screwed up.  This patch fixes it by dropping ret2 and just using ret
for the return value, and checking if we got an error before adding the bitmap
to the local list.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

fs/btrfs/free-space-cache.c

@@ -250,7 +250,7 @@ int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
 	pgoff_t index = 0;
 	unsigned long first_page_offset;
 	int num_checksums;
-	int ret = 0, ret2;
+	int ret = 0;
 
 	INIT_LIST_HEAD(&bitmaps);
 
@@ -421,11 +421,10 @@ int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
 					goto free_cache;
 				}
 				spin_lock(&ctl->tree_lock);
-				ret2 = link_free_space(ctl, e);
+				ret = link_free_space(ctl, e);
 				ctl->total_bitmaps++;
 				ctl->op->recalc_thresholds(ctl);
 				spin_unlock(&ctl->tree_lock);
-				list_add_tail(&e->list, &bitmaps);
 				if (ret) {
 					printk(KERN_ERR "Duplicate entries in "
 					       "free space cache, dumping\n");
@@ -434,6 +433,7 @@ int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
 					page_cache_release(page);
 					goto free_cache;
 				}
+				list_add_tail(&e->list, &bitmaps);
 			}
 
 			num_entries--;