static int inc_block_group_ro(struct btrfs_block_group *cache, int force)
{
	struct btrfs_space_info *sinfo = cache->space_info;
	u64 num_bytes;
	int ret = -ENOSPC;

	spin_lock(&sinfo->lock);
	spin_lock(&cache->lock);

	if (cache->swap_extents) {
		ret = -ETXTBSY;
		goto out;
	}

	if (cache->ro) {
		cache->ro++;
		ret = 0;
		goto out;
	}

	num_bytes = cache->length - cache->reserved - cache->pinned -
		    cache->bytes_super - cache->zone_unusable - cache->used;

	/*
	 * Data never overcommits, even in mixed mode, so do just the straight
	 * check of left over space in how much we have allocated.
	 */
	if (force) {
		ret = 0;
	} else if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA) {
		u64 sinfo_used = btrfs_space_info_used(sinfo, true);

		/*
		 * Here we make sure if we mark this bg RO, we still have enough
		 * free space as buffer.
		 */
		if (sinfo_used + num_bytes <= sinfo->total_bytes)
			ret = 0;
	} else {
		/*
		 * We overcommit metadata, so we need to do the
		 * btrfs_can_overcommit check here, and we need to pass in
		 * BTRFS_RESERVE_NO_FLUSH to give ourselves the most amount of
		 * leeway to allow us to mark this block group as read only.
		 */
		if (btrfs_can_overcommit(cache->fs_info, sinfo, num_bytes,
					 BTRFS_RESERVE_NO_FLUSH))
			ret = 0;
	}

	if (!ret) {
		sinfo->bytes_readonly += num_bytes;
		if (btrfs_is_zoned(cache->fs_info)) {
			/* Migrate zone_unusable bytes to readonly */
			sinfo->bytes_readonly += cache->zone_unusable;
			sinfo->bytes_zone_unusable -= cache->zone_unusable;
			cache->zone_unusable = 0;
		}
		cache->ro++;
		list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
	}
out:
	spin_unlock(&cache->lock);
	spin_unlock(&sinfo->lock);
	if (ret == -ENOSPC && btrfs_test_opt(cache->fs_info, ENOSPC_DEBUG)) {
		btrfs_info(cache->fs_info,
			"unable to make block group %llu ro", cache->start);
		btrfs_dump_space_info(cache->fs_info, cache->space_info, 0, 0);
	}
	return ret;
}
static int inc_block_group_ro(struct btrfs_block_group *cache, int force)
{
	struct btrfs_space_info *sinfo = cache->space_info;
	u64 num_bytes;
	int ret = -ENOSPC;

	spin_lock(&sinfo->lock);
	spin_lock(&cache->lock);

	if (cache->swap_extents) {
		ret = -ETXTBSY;
		goto out;
	}

	if (cache->ro) {
		cache->ro++;
		ret = 0;
		goto out;
	}

	num_bytes = cache->length - cache->reserved - cache->pinned -
		    cache->bytes_super - cache->zone_unusable - cache->used;

	 
	if (force) {
		ret = 0;
	} else if (sinfo->flags & BTRFS_BLOCK_GROUP_DATA) {
		u64 sinfo_used = btrfs_space_info_used(sinfo, true);

		 
		if (sinfo_used + num_bytes <= sinfo->total_bytes)
			ret = 0;
	} else {
		 
		if (btrfs_can_overcommit(cache->fs_info, sinfo, num_bytes,
					 BTRFS_RESERVE_NO_FLUSH))
			ret = 0;
	}

	if (!ret) {
		sinfo->bytes_readonly += num_bytes;
		if (btrfs_is_zoned(cache->fs_info)) {
			 
			sinfo->bytes_readonly += cache->zone_unusable;
			sinfo->bytes_zone_unusable -= cache->zone_unusable;
			cache->zone_unusable = 0;
		}
		cache->ro++;
		list_add_tail(&cache->ro_list, &sinfo->ro_bgs);
	}
out:
	spin_unlock(&cache->lock);
	spin_unlock(&sinfo->lock);
	if (ret == -ENOSPC && btrfs_test_opt(cache->fs_info, ENOSPC_DEBUG)) {
		btrfs_info(cache->fs_info,
			"unable to make block group %llu ro", cache->start);
		btrfs_dump_space_info(cache->fs_info, cache->space_info, 0, 0);
	}
	return ret;
}