Commit 53a788a7 authored by Alexander Gordeev's avatar Alexander Gordeev Committed by Jon Mason
Browse files

ntb: Split ntb_setup_msix() into separate BWD/SNB routines 



This is an cleanup effort to make ntb_setup_msix() more
readable - use ntb_setup_bwd_msix() to init MSI-Xs on
BWD hardware and ntb_setup_snb_msix() - on SNB hardware.

Function ntb_setup_snb_msix() also initializes MSI-Xs the
way it should has been done - looping pci_enable_msix()
until success or failure.

Signed-off-by: default avatarAlexander Gordeev <agordeev@redhat.com>
Signed-off-by: default avatarJon Mason <jon.mason@intel.com>
parent 77733513

drivers/ntb/ntb_hw.c

+102 −65
Original line number Diff line number Diff line
@@ -1080,104 +1080,141 @@ static irqreturn_t ntb_interrupt(int irq, void *dev) 
	return IRQ_HANDLED;

}



static int ntb_setup_msix(struct ntb_device *ndev)

static int ntb_setup_snb_msix(struct ntb_device *ndev, int msix_entries)

{

	struct pci_dev *pdev = ndev->pdev;

	struct msix_entry *msix;

	int msix_entries;

	int rc, i;



	msix_entries = pci_msix_vec_count(pdev);

	if (msix_entries < 0) {

		rc = msix_entries;

		goto err;

	} else if (msix_entries > ndev->limits.msix_cnt) {

		rc = -EINVAL;

		goto err;

	}



	ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries,

				     GFP_KERNEL);

	if (!ndev->msix_entries) {

		rc = -ENOMEM;

		goto err;

	}



	for (i = 0; i < msix_entries; i++)

		ndev->msix_entries[i].entry = i;

	if (msix_entries < ndev->limits.msix_cnt)

		return -ENOSPC;



	rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);

	if (rc < 0)

		goto err1;

	if (rc > 0) {

		/* On SNB, the link interrupt is always tied to 4th vector.  If

		 * we can't get all 4, then we can't use MSI-X.

		 */

		if (ndev->hw_type != BWD_HW) {

			rc = -EIO;

			goto err1;

		}



		dev_warn(&pdev->dev,

			 "Only %d MSI-X vectors.  Limiting the number of queues to that number.\n",

			 rc);

		msix_entries = rc;



		rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);

		if (rc)

			goto err1;

	}

		return rc;

	else if (rc > 0)

		return -ENOSPC;



	for (i = 0; i < msix_entries; i++) {

		msix = &ndev->msix_entries[i];

		WARN_ON(!msix->vector);



		/* Use the last MSI-X vector for Link status */

		if (ndev->hw_type == BWD_HW) {

			rc = request_irq(msix->vector, bwd_callback_msix_irq, 0,

					 "ntb-callback-msix", &ndev->db_cb[i]);

			if (rc)

				goto err2;

		} else {

		if (i == msix_entries - 1) {

			rc = request_irq(msix->vector,

					 xeon_event_msix_irq, 0,

					 "ntb-event-msix", ndev);

			if (rc)

					goto err2;

				goto err;

		} else {

			rc = request_irq(msix->vector,

					 xeon_callback_msix_irq, 0,

					 "ntb-callback-msix",

					 &ndev->db_cb[i]);

			if (rc)

					goto err2;

			}

				goto err;

		}

	}



	ndev->num_msix = msix_entries;

	if (ndev->hw_type == BWD_HW)

		ndev->max_cbs = msix_entries;

	else

	ndev->max_cbs = msix_entries - 1;



	return 0;



err2:

err:

	while (--i >= 0) {

		/* Code never reaches here for entry nr 'ndev->num_msix - 1' */

		msix = &ndev->msix_entries[i];

		if (ndev->hw_type != BWD_HW && i == ndev->num_msix - 1)

			free_irq(msix->vector, ndev);

		else

		free_irq(msix->vector, &ndev->db_cb[i]);

	}



	pci_disable_msix(pdev);

	ndev->num_msix = 0;



	return rc;

}



static int ntb_setup_bwd_msix(struct ntb_device *ndev, int msix_entries)

{

	struct pci_dev *pdev = ndev->pdev;

	struct msix_entry *msix;

	int rc, i;



retry:

	rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);

	if (rc < 0)

		return rc;

	else if (rc > 0) {

		dev_warn(&pdev->dev,

			 "Only %d MSI-X vectors. "

			 "Limiting the number of queues to that number.\n",

			 rc);

		msix_entries = rc;

		goto retry;

	}



	for (i = 0; i < msix_entries; i++) {

		msix = &ndev->msix_entries[i];

		WARN_ON(!msix->vector);



		rc = request_irq(msix->vector, bwd_callback_msix_irq, 0,

				 "ntb-callback-msix", &ndev->db_cb[i]);

		if (rc)

			goto err;

	}



	ndev->num_msix = msix_entries;

	ndev->max_cbs = msix_entries;



	return 0;



err:

	while (--i >= 0)

		free_irq(msix->vector, &ndev->db_cb[i]);



	pci_disable_msix(pdev);

	ndev->num_msix = 0;



	return rc;

}



static int ntb_setup_msix(struct ntb_device *ndev)

{

	struct pci_dev *pdev = ndev->pdev;

	int msix_entries;

	int rc, i;



	msix_entries = pci_msix_vec_count(pdev);

	if (msix_entries < 0) {

		rc = msix_entries;

		goto err;

	} else if (msix_entries > ndev->limits.msix_cnt) {

		rc = -EINVAL;

		goto err;

	}



	ndev->msix_entries = kmalloc(sizeof(struct msix_entry) * msix_entries,

				     GFP_KERNEL);

	if (!ndev->msix_entries) {

		rc = -ENOMEM;

		goto err;

	}



	for (i = 0; i < msix_entries; i++)

		ndev->msix_entries[i].entry = i;



	if (ndev->hw_type == BWD_HW)

		rc = ntb_setup_bwd_msix(ndev, msix_entries);

	else

		rc = ntb_setup_snb_msix(ndev, msix_entries);

	if (rc)

		goto err1;



	return 0;



err1:

	kfree(ndev->msix_entries);

	dev_err(&pdev->dev, "Error allocating MSI-X interrupt\n");

err:

	ndev->num_msix = 0;

	dev_err(&pdev->dev, "Error allocating MSI-X interrupt\n");

	return rc;

}

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