[RFC PATCH 1/5] pci/p2p: add a function to test peer to peer capability

Logan Gunthorpe logang at deltatee.com
Tue Jan 29 18:24:09 UTC 2019



On 2019-01-29 10:47 a.m., jglisse at redhat.com wrote:
> +bool pci_test_p2p(struct device *devA, struct device *devB)
> +{
> +	struct pci_dev *pciA, *pciB;
> +	bool ret;
> +	int tmp;
> +
> +	/*
> +	 * For now we only support PCIE peer to peer but other inter-connect
> +	 * can be added.
> +	 */
> +	pciA = find_parent_pci_dev(devA);
> +	pciB = find_parent_pci_dev(devB);
> +	if (pciA == NULL || pciB == NULL) {
> +		ret = false;
> +		goto out;
> +	}
> +
> +	tmp = upstream_bridge_distance(pciA, pciB, NULL);
> +	ret = tmp < 0 ? false : true;
> +
> +out:
> +	pci_dev_put(pciB);
> +	pci_dev_put(pciA);
> +	return false;
> +}
> +EXPORT_SYMBOL_GPL(pci_test_p2p);

This function only ever returns false....

Logan


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