Commit 3fad3a26 authored by Nicolin Chen's avatar Nicolin Chen Committed by Alex Williamson
Browse files

vfio/ap: Change saved_pfn to saved_iova 



The vfio_ap_ops code maintains both nib address and its PFN, which
is redundant, merely because vfio_pin/unpin_pages API wanted pfn.
Since vfio_pin/unpin_pages() now accept "iova", change "saved_pfn"
to "saved_iova" and remove pfn in the vfio_ap_validate_nib().

Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarTony Krowiak <akrowiak@linux.ibm.com>
Tested-by: default avatarEric Farman <farman@linux.ibm.com>
Signed-off-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/20220723020256.30081-7-nicolinc@nvidia.com


Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 44abdd16

drivers/s390/crypto/vfio_ap_ops.c

+17 −25
Original line number Diff line number Diff line
@@ -112,7 +112,7 @@ static void vfio_ap_wait_for_irqclear(int apqn) 
 *

 * Unregisters the ISC in the GIB when the saved ISC not invalid.

 * Unpins the guest's page holding the NIB when it exists.

 * Resets the saved_pfn and saved_isc to invalid values.

 * Resets the saved_iova and saved_isc to invalid values.

 */

static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q)

{
@@ -123,9 +123,9 @@ static void vfio_ap_free_aqic_resources(struct vfio_ap_queue *q) 
		kvm_s390_gisc_unregister(q->matrix_mdev->kvm, q->saved_isc);

		q->saved_isc = VFIO_AP_ISC_INVALID;

	}

	if (q->saved_pfn && !WARN_ON(!q->matrix_mdev)) {

		vfio_unpin_pages(&q->matrix_mdev->vdev, q->saved_pfn << PAGE_SHIFT, 1);

		q->saved_pfn = 0;

	if (q->saved_iova && !WARN_ON(!q->matrix_mdev)) {

		vfio_unpin_pages(&q->matrix_mdev->vdev, q->saved_iova, 1);

		q->saved_iova = 0;

	}

}
@@ -189,27 +189,19 @@ static struct ap_queue_status vfio_ap_irq_disable(struct vfio_ap_queue *q) 
 *

 * @vcpu: the object representing the vcpu executing the PQAP(AQIC) instruction.

 * @nib: the location for storing the nib address.

 * @g_pfn: the location for storing the page frame number of the page containing

 *	   the nib.

 *

 * When the PQAP(AQIC) instruction is executed, general register 2 contains the

 * address of the notification indicator byte (nib) used for IRQ notification.

 * This function parses the nib from gr2 and calculates the page frame

 * number for the guest of the page containing the nib. The values are

 * stored in @nib and @g_pfn respectively.

 *

 * The g_pfn of the nib is then validated to ensure the nib address is valid.

 * This function parses and validates the nib from gr2.

 *

 * Return: returns zero if the nib address is a valid; otherwise, returns

 *	   -EINVAL.

 */

static int vfio_ap_validate_nib(struct kvm_vcpu *vcpu, unsigned long *nib,

				unsigned long *g_pfn)

static int vfio_ap_validate_nib(struct kvm_vcpu *vcpu, dma_addr_t *nib)

{

	*nib = vcpu->run->s.regs.gprs[2];

	*g_pfn = *nib >> PAGE_SHIFT;



	if (kvm_is_error_hva(gfn_to_hva(vcpu->kvm, *g_pfn)))

	if (kvm_is_error_hva(gfn_to_hva(vcpu->kvm, *nib >> PAGE_SHIFT)))

		return -EINVAL;



	return 0;
@@ -239,34 +231,34 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q, 
						 int isc,

						 struct kvm_vcpu *vcpu)

{

	unsigned long nib;

	struct ap_qirq_ctrl aqic_gisa = {};

	struct ap_queue_status status = {};

	struct kvm_s390_gisa *gisa;

	int nisc;

	struct kvm *kvm;

	unsigned long g_pfn, h_pfn;

	unsigned long h_pfn;

	phys_addr_t h_nib;

	dma_addr_t nib;

	int ret;



	/* Verify that the notification indicator byte address is valid */

	if (vfio_ap_validate_nib(vcpu, &nib, &g_pfn)) {

		VFIO_AP_DBF_WARN("%s: invalid NIB address: nib=%#lx, g_pfn=%#lx, apqn=%#04x\n",

				 __func__, nib, g_pfn, q->apqn);

	if (vfio_ap_validate_nib(vcpu, &nib)) {

		VFIO_AP_DBF_WARN("%s: invalid NIB address: nib=%pad, apqn=%#04x\n",

				 __func__, &nib, q->apqn);



		status.response_code = AP_RESPONSE_INVALID_ADDRESS;

		return status;

	}



	ret = vfio_pin_pages(&q->matrix_mdev->vdev, g_pfn << PAGE_SHIFT, 1,

	ret = vfio_pin_pages(&q->matrix_mdev->vdev, nib, 1,

			     IOMMU_READ | IOMMU_WRITE, &h_pfn);

	switch (ret) {

	case 1:

		break;

	default:

		VFIO_AP_DBF_WARN("%s: vfio_pin_pages failed: rc=%d,"

				 "nib=%#lx, g_pfn=%#lx, apqn=%#04x\n",

				 __func__, ret, nib, g_pfn, q->apqn);

				 "nib=%pad, apqn=%#04x\n",

				 __func__, ret, &nib, q->apqn);



		status.response_code = AP_RESPONSE_INVALID_ADDRESS;

		return status;
@@ -296,12 +288,12 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q, 
	case AP_RESPONSE_NORMAL:

		/* See if we did clear older IRQ configuration */

		vfio_ap_free_aqic_resources(q);

		q->saved_pfn = g_pfn;

		q->saved_iova = nib;

		q->saved_isc = isc;

		break;

	case AP_RESPONSE_OTHERWISE_CHANGED:

		/* We could not modify IRQ setings: clear new configuration */

		vfio_unpin_pages(&q->matrix_mdev->vdev, g_pfn << PAGE_SHIFT, 1);

		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);

		kvm_s390_gisc_unregister(kvm, isc);

		break;

	default:

drivers/s390/crypto/vfio_ap_private.h

+2 −2
Original line number Diff line number Diff line
@@ -99,13 +99,13 @@ struct ap_matrix_mdev { 
 * struct vfio_ap_queue - contains the data associated with a queue bound to the

 *			  vfio_ap device driver

 * @matrix_mdev: the matrix mediated device

 * @saved_pfn: the guest PFN pinned for the guest

 * @saved_iova: the notification indicator byte (nib) address

 * @apqn: the APQN of the AP queue device

 * @saved_isc: the guest ISC registered with the GIB interface

 */

struct vfio_ap_queue {

	struct ap_matrix_mdev *matrix_mdev;

	unsigned long saved_pfn;

	dma_addr_t saved_iova;

	int	apqn;

#define VFIO_AP_ISC_INVALID 0xff

	unsigned char saved_isc;