When restoring btrfs image, the total_bytes of device item is not
updated correctly. In fact total_bytes can be left 0 for restored image.
It doesn't trigger any error because btrfs check never checks
total_bytes of dev item.
However this is going to change.
Fix it by populating total_bytes of device item with the end position of
last dev extent to make later btrfs check happy.
Signed-off-by: Qu Wenruo <wqu@xxxxxxxx>
---
image/main.c | 48 +++++++++++++++++++++++++++++++++++++++++++++---
1 file changed, 45 insertions(+), 3 deletions(-)
diff --git a/image/main.c b/image/main.c
index 351c5a256938..d5b89bc3149f 100644
--- a/image/main.c
+++ b/image/main.c
@@ -2082,15 +2082,17 @@ static void remap_overlapping_chunks(struct mdrestore_struct *mdres)
}
static int fixup_devices(struct btrfs_fs_info *fs_info,
- struct mdrestore_struct *mdres, off_t dev_size)
+ struct mdrestore_struct *mdres, int out_fd)
{
struct btrfs_trans_handle *trans;
struct btrfs_dev_item *dev_item;
+ struct btrfs_dev_extent *dev_ext;
struct btrfs_path path;
struct extent_buffer *leaf;
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_key key;
u64 devid, cur_devid;
+ u64 dev_size; /* Get from last dev extents */
int ret;
trans = btrfs_start_transaction(fs_info->tree_root, 1);
@@ -2101,16 +2103,56 @@ static int fixup_devices(struct btrfs_fs_info *fs_info,
dev_item = &fs_info->super_copy->dev_item;
+ btrfs_init_path(&path);
devid = btrfs_stack_device_id(dev_item);
+ key.objectid = devid;
+ key.type = BTRFS_DEV_EXTENT_KEY;
+ key.offset = (u64)-1;
+
+ ret = btrfs_search_slot(NULL, fs_info->dev_root, &key, &path, 0, 0);
+ if (ret < 0) {
+ error("failed to locate last dev extent of devid %llu: %s",
+ devid, strerror(-ret));
+ btrfs_release_path(&path);
+ return ret;
+ }
+ if (ret == 0) {
+ error("found invalid dev extent devid %llu offset -1",
+ devid);
+ btrfs_release_path(&path);
+ return -EUCLEAN;
+ }
+ ret = btrfs_previous_item(fs_info->dev_root, &path, devid,
+ BTRFS_DEV_EXTENT_KEY);
+ if (ret > 0)
+ ret = -ENOENT;
+ if (ret < 0) {
+ error("failed to locate last dev extent of devid %llu: %s",
+ devid, strerror(-ret));
+ btrfs_release_path(&path);
+ return ret;
+ }
+
+ btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
+ dev_ext = btrfs_item_ptr(path.nodes[0], path.slots[0],
+ struct btrfs_dev_extent);
+ dev_size = key.offset + btrfs_dev_extent_length(path.nodes[0], dev_ext);
+ btrfs_release_path(&path);
+
btrfs_set_stack_device_total_bytes(dev_item, dev_size);
btrfs_set_stack_device_bytes_used(dev_item, mdres->alloced_chunks);
+ /* Don't forget to enlarge the real file */
+ ret = ftruncate64(out_fd, dev_size);
+ if (ret < 0) {
+ error("failed to enlarge result image: %s", strerror(errno));
+ return -errno;
+ }
key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
key.type = BTRFS_DEV_ITEM_KEY;
key.offset = 0;
- btrfs_init_path(&path);
again:
ret = btrfs_search_slot(trans, root, &key, &path, -1, 1);
@@ -2275,7 +2317,7 @@ static int restore_metadump(const char *input, FILE *out, int old_restore,
return 1;
}
- ret = fixup_devices(info, &mdrestore, st.st_size);
+ ret = fixup_devices(info, &mdrestore, fileno(out));
close_ctree(info->chunk_root);
if (ret)
goto out;
--
2.19.1
