int ntb_msi_setup_mws()

in msi.c [97:167]

• 57 lines of code
• 12 McCabe index (conditional complexity)

int ntb_msi_setup_mws(struct ntb_dev *ntb)
{
	struct msi_desc *desc;
	u64 addr;
	int peer, peer_widx;
	resource_size_t addr_align, size_align, size_max;
	resource_size_t mw_size = SZ_32K;
	resource_size_t mw_min_size = mw_size;
	int i;
	int ret;

	if (!ntb->msi)
		return -EINVAL;

	msi_lock_descs(&ntb->pdev->dev);
	desc = msi_first_desc(&ntb->pdev->dev, MSI_DESC_ASSOCIATED);
	addr = desc->msg.address_lo + ((uint64_t)desc->msg.address_hi << 32);
	msi_unlock_descs(&ntb->pdev->dev);

	for (peer = 0; peer < ntb_peer_port_count(ntb); peer++) {
		peer_widx = ntb_peer_highest_mw_idx(ntb, peer);
		if (peer_widx < 0)
			return peer_widx;

		ret = ntb_mw_get_align(ntb, peer, peer_widx, &addr_align,
				       NULL, NULL);
		if (ret)
			return ret;

		addr &= ~(addr_align - 1);
	}

	for (peer = 0; peer < ntb_peer_port_count(ntb); peer++) {
		peer_widx = ntb_peer_highest_mw_idx(ntb, peer);
		if (peer_widx < 0) {
			ret = peer_widx;
			goto error_out;
		}

		ret = ntb_mw_get_align(ntb, peer, peer_widx, NULL,
				       &size_align, &size_max);
		if (ret)
			goto error_out;

		mw_size = round_up(mw_size, size_align);
		mw_size = max(mw_size, size_max);
		if (mw_size < mw_min_size)
			mw_min_size = mw_size;

		ret = ntb_mw_set_trans(ntb, peer, peer_widx,
				       addr, mw_size);
		if (ret)
			goto error_out;
	}

	ntb->msi->base_addr = addr;
	ntb->msi->end_addr = addr + mw_min_size;

	return 0;

error_out:
	for (i = 0; i < peer; i++) {
		peer_widx = ntb_peer_highest_mw_idx(ntb, peer);
		if (peer_widx < 0)
			continue;

		ntb_mw_clear_trans(ntb, i, peer_widx);
	}

	return ret;
}