1 files changed, 69 insertions, 0 deletions
diff --git a/volumes.c b/volumes.c
index e3654a4c..652f0087 100644
--- a/volumes.c
+++ b/volumes.c
@@ -2356,3 +2356,72 @@ u64 btrfs_stripe_length(struct btrfs_fs_info *fs_info,
 	}
 	return stripe_len;
 }
+
+/*
+ * Return 0 if size of @device is already good
+ * Return >0 if size of @device is not aligned but fixed without problems
+ * Return <0 if something wrong happened when aligning the size of @device
+ */
+int btrfs_fix_device_size(struct btrfs_fs_info *fs_info,
+			  struct btrfs_device *device)
+{
+	struct btrfs_trans_handle *trans;
+	struct btrfs_key key;
+	struct btrfs_path path;
+	struct btrfs_root *chunk_root = fs_info->chunk_root;
+	struct btrfs_dev_item *di;
+	u64 old_bytes = device->total_bytes;
+	int ret;
+
+	if (IS_ALIGNED(old_bytes, fs_info->sectorsize))
+		return 0;
+
+	/* Align the in-memory total_bytes first, and use it as correct size */
+	device->total_bytes = round_down(device->total_bytes,
+					 fs_info->sectorsize);
+
+	key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
+	key.type = BTRFS_DEV_ITEM_KEY;
+	key.offset = device->devid;
+
+	trans = btrfs_start_transaction(chunk_root, 1);
+	if (IS_ERR(trans)) {
+		ret = PTR_ERR(trans);
+		error("error starting transaction: %d (%s)",
+		      ret, strerror(-ret));
+		return ret;
+	}
+
+	btrfs_init_path(&path);
+	ret = btrfs_search_slot(trans, chunk_root, &key, &path, 0, 1);
+	if (ret > 0) {
+		error("failed to find DEV_ITEM for devid %llu", device->devid);
+		ret = -ENOENT;
+		goto err;
+	}
+	if (ret < 0) {
+		error("failed to search chunk root: %d (%s)",
+			ret, strerror(-ret));
+		goto err;
+	}
+	di = btrfs_item_ptr(path.nodes[0], path.slots[0], struct btrfs_dev_item);
+	btrfs_set_device_total_bytes(path.nodes[0], di, device->total_bytes);
+	btrfs_mark_buffer_dirty(path.nodes[0]);
+	ret = btrfs_commit_transaction(trans, chunk_root);
+	if (ret < 0) {
+		error("failed to commit current transaction: %d (%s)",
+			ret, strerror(-ret));
+		btrfs_release_path(&path);
+		return ret;
+	}
+	btrfs_release_path(&path);
+	printf("Fixed device size for devid %llu, old size: %llu new size: %llu\n",
+		device->devid, old_bytes, device->total_bytes);
+	return 1;
+
+err:
+	/* We haven't modified anything, it's OK to commit current trans */
+	btrfs_commit_transaction(trans, chunk_root);
+	btrfs_release_path(&path);
+	return ret;
+}