path: root/drivers/s390/crypto/ap_queue.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright IBM Corp. 2016, 2023
 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
 *
 * Adjunct processor bus, queue related code.
 */

#define KMSG_COMPONENT "ap"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/init.h>
#include <linux/slab.h>
#include <asm/facility.h>

#include "ap_bus.h"
#include "ap_debug.h"

static void __ap_flush_queue(struct ap_queue *aq);

/*
 * some AP queue helper functions
 */

static inline bool ap_q_supports_bind(struct ap_queue *aq)
{
	return aq->card->hwinfo.ep11 || aq->card->hwinfo.accel;
}

static inline bool ap_q_supports_assoc(struct ap_queue *aq)
{
	return aq->card->hwinfo.ep11;
}

static inline bool ap_q_needs_bind(struct ap_queue *aq)
{
	return ap_q_supports_bind(aq) && ap_sb_available();
}

/**
 * ap_queue_enable_irq(): Enable interrupt support on this AP queue.
 * @aq: The AP queue
 * @ind: the notification indicator byte
 *
 * Enables interruption on AP queue via ap_aqic(). Based on the return
 * value it waits a while and tests the AP queue if interrupts
 * have been switched on using ap_test_queue().
 */
static int ap_queue_enable_irq(struct ap_queue *aq, void *ind)
{
	union ap_qirq_ctrl qirqctrl = { .value = 0 };
	struct ap_queue_status status;

	qirqctrl.ir = 1;
	qirqctrl.isc = AP_ISC;
	status = ap_aqic(aq->qid, qirqctrl, virt_to_phys(ind));
	if (status.async)
		return -EPERM;
	switch (status.response_code) {
	case AP_RESPONSE_NORMAL:
	case AP_RESPONSE_OTHERWISE_CHANGED:
		return 0;
	case AP_RESPONSE_Q_NOT_AVAIL:
	case AP_RESPONSE_DECONFIGURED:
	case AP_RESPONSE_CHECKSTOPPED:
	case AP_RESPONSE_INVALID_ADDRESS:
		pr_err("Registering adapter interrupts for AP device %02x.%04x failed\n",
		       AP_QID_CARD(aq->qid),
		       AP_QID_QUEUE(aq->qid));
		return -EOPNOTSUPP;
	case AP_RESPONSE_RESET_IN_PROGRESS:
	case AP_RESPONSE_BUSY:
	default:
		return -EBUSY;
	}
}

/**
 * __ap_send(): Send message to adjunct processor queue.
 * @qid: The AP queue number
 * @psmid: The program supplied message identifier
 * @msg: The message text
 * @msglen: The message length
 * @special: Special Bit
 *
 * Returns AP queue status structure.
 * Condition code 1 on NQAP can't happen because the L bit is 1.
 * Condition code 2 on NQAP also means the send is incomplete,
 * because a segment boundary was reached. The NQAP is repeated.
 */
static inline struct ap_queue_status
__ap_send(ap_qid_t qid, unsigned long psmid, void *msg, size_t msglen,
	  int special)
{
	if (special)
		qid |= 0x400000UL;
	return ap_nqap(qid, psmid, msg, msglen);
}

/* State machine definitions and helpers */

static enum ap_sm_wait ap_sm_nop(struct ap_queue *aq)
{
	return AP_SM_WAIT_NONE;
}

/**
 * ap_sm_recv(): Receive pending reply messages from an AP queue but do
 *	not change the state of the device.
 * @aq: pointer to the AP queue
 *
 * Returns AP_SM_WAIT_NONE, AP_SM_WAIT_AGAIN, or AP_SM_WAIT_INTERRUPT
 */
static struct ap_queue_status ap_sm_recv(struct ap_queue *aq)
{