Re: [PATCH 08/11] PCI/IDE: Add IDE establishment helpers

[Aneesh Kumar K.V <aneesh.kumar@kernel.org>]

Hi Dan,

Dan Williams <dan.j.williams@intel.com> writes:
> +int pci_ide_stream_setup(struct pci_dev *pdev, struct pci_ide *ide,
> +			 enum pci_ide_flags flags)
> +{
> +	struct pci_host_bridge *hb = pci_find_host_bridge(pdev->bus);
> +	struct pci_dev *rp = pcie_find_root_port(pdev);
> +	int mem = 0, rc;
> +
> +	if (ide->stream_id < 0 || ide->stream_id > U8_MAX) {
> +		pci_err(pdev, "Setup fail: Invalid stream id: %d\n", ide->stream_id);
> +		return -ENXIO;
> +	}
> +
> +	if (test_and_set_bit_lock(ide->stream_id, hb->ide_stream_ids)) {
> +		pci_err(pdev, "Setup fail: Busy stream id: %d\n",
> +			ide->stream_id);
> +		return -EBUSY;
> +	}
> +

Considering we are using the hostbridge ide_stream_ids bitmap, why is
the stream_id allocation not generic? ie, any reason why a stream id alloc
like below will not work?

static int pcie_ide_sel_streamid_alloc(struct pci_dev *pdev)
{
	int stream_id;
	struct pci_host_bridge *hb;

	hb = pci_find_host_bridge(pdev->bus);

	stream_id = find_first_zero_bit(hb->ide_stream_ids, hb->nr_ide_streams);
	if (stream_id >= hb->nr_ide_streams)
		return -EBUSY;

	return stream_id;
}

-aneesh