On Fri, Oct 30, 2020 at 10:51:22PM +0900, Naohiro Aota wrote:
> + struct btrfs_key found_key;
> + int slot;
> + int ret;
> + u64 length;
> +
> + path = btrfs_alloc_path();
> + if (!path)
> + return -ENOMEM;
> +
> + search_key.objectid = cache->start + cache->length;
> + search_key.type = 0;
> + search_key.offset = 0;
> +
> + ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
> + if (ret < 0)
> + goto out;
> + ASSERT(ret != 0);
This should be a runtime check not an assert, if this happens it's
likely a corruption
> + slot = path->slots[0];
> + leaf = path->nodes[0];
> + ASSERT(slot != 0);
Same
> + slot--;
> + btrfs_item_key_to_cpu(leaf, &found_key, slot);
> +
> + if (found_key.objectid < cache->start) {
> + *offset_ret = 0;
> + } else if (found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
> + struct btrfs_key extent_item_key;
> +
> + if (found_key.objectid != cache->start) {
> + ret = -EUCLEAN;
> + goto out;
> + }
> +
> + length = 0;
> +
> + /* metadata may have METADATA_ITEM_KEY */
/* Metadata ... */
> + if (slot == 0) {
> + btrfs_set_path_blocking(path);
> + ret = btrfs_prev_leaf(root, path);
> + if (ret < 0)
> + goto out;
> + if (ret == 0) {
> + slot = btrfs_header_nritems(leaf) - 1;
> + btrfs_item_key_to_cpu(leaf, &extent_item_key,
> + slot);
> + }
> + } else {
> + btrfs_item_key_to_cpu(leaf, &extent_item_key, slot - 1);
> + ret = 0;
> + }
> +
> + if (ret == 0 &&
> + extent_item_key.objectid == cache->start) {
> + if (extent_item_key.type == BTRFS_METADATA_ITEM_KEY)
if (...) {
> + length = fs_info->nodesize;
} else if (...) {
> + else if (extent_item_key.type == BTRFS_EXTENT_ITEM_KEY)
> + length = extent_item_key.offset;
} else {
> + else {
> + ret = -EUCLEAN;
> + goto out;
> + }
> + }
> +
> + *offset_ret = length;
> + } else if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
> + found_key.type == BTRFS_METADATA_ITEM_KEY) {
> +
> + if (found_key.type == BTRFS_EXTENT_ITEM_KEY)
> + length = found_key.offset;
> + else
> + length = fs_info->nodesize;
> +
> + if (!(found_key.objectid >= cache->start &&
> + found_key.objectid + length <=
> + cache->start + cache->length)) {
> + ret = -EUCLEAN;
> + goto out;
> + }
> + *offset_ret = found_key.objectid + length - cache->start;
> + } else {
> + ret = -EUCLEAN;
> + goto out;
> + }
> + ret = 0;
> +
> +out:
> + btrfs_free_path(path);
> + return ret;
> +}
> +
> int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
> {
> struct btrfs_fs_info *fs_info = cache->fs_info;
> @@ -754,6 +852,7 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
> int i;
> unsigned int nofs_flag;
> u64 *alloc_offsets = NULL;
> + u64 emulated_offset = 0;
> u32 num_sequential = 0, num_conventional = 0;
>
> if (!btrfs_is_zoned(fs_info))
> @@ -854,12 +953,12 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
> }
>
> if (num_conventional > 0) {
> - /*
> - * Since conventional zones does not have write pointer, we
> - * cannot determine alloc_offset from the pointer
> - */
> - ret = -EINVAL;
> - goto out;
> + ret = emulate_write_pointer(cache, &emulated_offset);
> + if (ret || map->num_stripes == num_conventional) {
> + if (!ret)
> + cache->alloc_offset = emulated_offset;
> + goto out;
> + }
> }
>
> switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
> @@ -881,6 +980,14 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache)
> }
>
> out:
> + /* an extent is allocated after the write pointer */
/* An ... */
> + if (num_conventional && emulated_offset > cache->alloc_offset) {
> + btrfs_err(fs_info,
> + "got wrong write pointer in BG %llu: %llu > %llu",
"zoned: got wrong write pointer in block group %llu found %llu emulated %llu"
> + logical, emulated_offset, cache->alloc_offset);
> + ret = -EIO;
> + }
> +
> kfree(alloc_offsets);
> free_extent_map(em);
>
> --
> 2.27.0
