// SPDX-License-Identifier: GPL-2.0+
/*
* Adjunct processor matrix VFIO device driver callbacks.
*
* Copyright IBM Corp. 2018
*
* Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
* Halil Pasic <pasic@linux.ibm.com>
* Pierre Morel <pmorel@linux.ibm.com>
*/
#include <linux/string.h>
#include <linux/vfio.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/ctype.h>
#include <linux/bitops.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <asm/kvm.h>
#include <asm/zcrypt.h>
#include "vfio_ap_private.h"
#define VFIO_AP_MDEV_TYPE_HWVIRT "passthrough"
#define VFIO_AP_MDEV_NAME_HWVIRT "VFIO AP Passthrough Device"
static int vfio_ap_mdev_reset_queues(struct mdev_device *mdev);
static struct vfio_ap_queue *vfio_ap_find_queue(int apqn);
static int match_apqn(struct device *dev, const void *data)
{
struct vfio_ap_queue *q = dev_get_drvdata(dev);
return (q->apqn == *(int *)(data)) ? 1 : 0;
}
/**
* vfio_ap_get_queue: Retrieve a queue with a specific APQN from a list
* @matrix_mdev: the associated mediated matrix
* @apqn: The queue APQN
*
* Retrieve a queue with a specific APQN from the list of the
* devices of the vfio_ap_drv.
* Verify that the APID and the APQI are set in the matrix.
*
* Returns the pointer to the associated vfio_ap_queue
*/
static struct vfio_ap_queue *vfio_ap_get_queue(
struct ap_matrix_mdev *matrix_mdev,
int apqn)
{
struct vfio_ap_queue *q;
if (!test_bit_inv(AP_QID_CARD(apqn), matrix_mdev->matrix.apm))
return NULL;
if (!test_bit_inv(AP_QID_QUEUE(apqn), matrix_mdev->matrix.aqm))
return NULL;
q = vfio_ap_find_queue(apqn);
if (q)
q->matrix_mdev = matrix_mdev;
return q;
}
/**
* vfio_ap_wait_for_irqclear
* @apqn: The AP Queue number
*
* Checks the IRQ bit for the status of this APQN using ap_tapq.
* Returns if the ap_tapq function succeeded and the bit is clear.
* Returns if ap_tapq function failed with invalid, deconfigured or
* checkstopped AP.
* Otherwise retries up to 5 times after waiting 20ms.
*
*/
static void vfio_ap_wait_for_irqclear(int apqn)
{
struct ap_queue_status status;
int retry = 5;
do {
status = ap_tapq(apqn, NULL);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
case AP_RESPONSE_RESET_IN_PROGRESS:
if (!status.irq_enabled)
return;
fallthrough;
case AP_RESPONSE_BUSY:
msleep(20);
break;
case AP_RESPONSE_Q_NOT_AVAIL:
case AP_RESPONSE_DECONFIGURED:
case AP_RESPONSE_CHECKSTOPPED:
default:
WARN_ONCE(1, "%s: tapq rc %02x: %04x\n", __func__,
status.response_code, apqn);
return;
}
} while (--retry);
WARN_ONCE(1, "%s: tapq rc %02x: %04x could not clear IR bit\n",
__func__, status.response_code, apqn);
}
/**
* vfio_ap_free_aqic_resources
* @q: The vfio_ap_queue
*
* Unregisters the ISC in the GIB when the saved ISC not invalid.
* Unpin the guest's page holding the NIB when it exist.
* Reset the saved_pfn and saved_isc to invalid values.
*
