linux/drivers/s390/crypto/ap_queue.c

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/*
* Copyright IBM Corp. 2016
* 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_asm.h"
/**
* ap_queue_enable_interruption(): Enable interruption on an AP queue.
* @qid: The AP queue number
* @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_interruption(struct ap_queue *aq, void *ind)
{
struct ap_queue_status status;
status = ap_aqic(aq->qid, ind);
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
* @length: 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 long psmid, void *msg, size_t length,
unsigned int special)
{
if (special == 1)
qid |= 0x400000UL;
return ap_nqap(qid, psmid, msg, length);
}
int ap_send(ap_qid_t qid, unsigned long long psmid, void *msg, size_t length)
{
struct ap_queue_status status;
status = __ap_send(qid, psmid, msg, length, 0);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
return 0;
case AP_RESPONSE_Q_FULL:
case AP_RESPONSE_RESET_IN_PROGRESS:
return -EBUSY;
case AP_RESPONSE_REQ_FAC_NOT_INST:
return -EINVAL;
default: /* Device is gone. */
return -ENODEV;
}
}
EXPORT_SYMBOL(ap_send);
int ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length)
{
struct ap_queue_status status;
if (msg == NULL)
return -EINVAL;
status = ap_dqap(qid, psmid, msg, length);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
return 0;
case AP_RESPONSE_NO_PENDING_REPLY:
if (status.queue_empty)
return -ENOENT;
return -EBUSY;
case AP_RESPONSE_RESET_IN_PROGRESS:
return -EBUSY;
default:
return -ENODEV;
}
}
EXPORT_SYMBOL(ap_recv);
/* State machine definitions and helpers */
static enum ap_wait ap_sm_nop(struct ap_queue *aq)
{
return AP_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_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT
*/
static struct ap_queue_status ap_sm_recv(struct ap_queue *aq)
{
struct ap_queue_status status;
struct ap_message *ap_msg;
status = ap_dqap(aq->qid, &aq->reply->psmid,
aq->reply->message, aq->reply->length);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
aq->queue_count--;
if (aq->queue_count > 0)
mod_timer(&aq->timeout,
jiffies + aq->request_timeout);
list_for_each_entry(ap_msg, &aq->pendingq, list) {
if (ap_msg->psmid != aq->reply->psmid)
continue;
list_del_init(&ap_msg->list);
aq->pendingq_count--;
ap_msg->receive(aq, ap_msg, aq->reply);
break;
}
case AP_RESPONSE_NO_PENDING_REPLY:
if (!status.queue_empty || aq->queue_count <= 0)
break;
/* The card shouldn't forget requests but who knows. */
aq->queue_count = 0;
list_splice_init(&aq->pendingq, &aq->requestq);
aq->requestq_count += aq->pendingq_count;
aq->pendingq_count = 0;
break;
default:
break;
}
return status;
}
/**
* ap_sm_read(): Receive pending reply messages from an AP queue.
* @aq: pointer to the AP queue
*
* Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT
*/
static enum ap_wait ap_sm_read(struct ap_queue *aq)
{
struct ap_queue_status status;
if (!aq->reply)
return AP_WAIT_NONE;
status = ap_sm_recv(aq);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
if (aq->queue_count > 0) {
aq->state = AP_STATE_WORKING;
return AP_WAIT_AGAIN;
}
aq->state = AP_STATE_IDLE;
return AP_WAIT_NONE;
case AP_RESPONSE_NO_PENDING_REPLY:
if (aq->queue_count > 0)
return AP_WAIT_INTERRUPT;
aq->state = AP_STATE_IDLE;
return AP_WAIT_NONE;
default:
aq->state = AP_STATE_BORKED;
return AP_WAIT_NONE;
}
}
/**
* ap_sm_suspend_read(): Receive pending reply messages from an AP queue
* without changing the device state in between. In suspend mode we don't
* allow sending new requests, therefore just fetch pending replies.
* @aq: pointer to the AP queue
*
* Returns AP_WAIT_NONE or AP_WAIT_AGAIN
*/
static enum ap_wait ap_sm_suspend_read(struct ap_queue *aq)
{
struct ap_queue_status status;
if (!aq->reply)
return AP_WAIT_NONE;
status = ap_sm_recv(aq);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
if (aq->queue_count > 0)
return AP_WAIT_AGAIN;
/* fall through */
default:
return AP_WAIT_NONE;
}
}
/**
* ap_sm_write(): Send messages from the request queue to an AP queue.
* @aq: pointer to the AP queue
*
* Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT
*/
static enum ap_wait ap_sm_write(struct ap_queue *aq)
{
struct ap_queue_status status;
struct ap_message *ap_msg;
if (aq->requestq_count <= 0)
return AP_WAIT_NONE;
/* Start the next request on the queue. */
ap_msg = list_entry(aq->requestq.next, struct ap_message, list);
status = __ap_send(aq->qid, ap_msg->psmid,
ap_msg->message, ap_msg->length, ap_msg->special);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
aq->queue_count++;
if (aq->queue_count == 1)
mod_timer(&aq->timeout, jiffies + aq->request_timeout);
list_move_tail(&ap_msg->list, &aq->pendingq);
aq->requestq_count--;
aq->pendingq_count++;
if (aq->queue_count < aq->card->queue_depth) {
aq->state = AP_STATE_WORKING;
return AP_WAIT_AGAIN;
}
/* fall through */
case AP_RESPONSE_Q_FULL:
aq->state = AP_STATE_QUEUE_FULL;
return AP_WAIT_INTERRUPT;
case AP_RESPONSE_RESET_IN_PROGRESS:
aq->state = AP_STATE_RESET_WAIT;
return AP_WAIT_TIMEOUT;
case AP_RESPONSE_MESSAGE_TOO_BIG:
case AP_RESPONSE_REQ_FAC_NOT_INST:
list_del_init(&ap_msg->list);
aq->requestq_count--;
ap_msg->rc = -EINVAL;
ap_msg->receive(aq, ap_msg, NULL);
return AP_WAIT_AGAIN;
default:
aq->state = AP_STATE_BORKED;
return AP_WAIT_NONE;
}
}
/**
* ap_sm_read_write(): Send and receive messages to/from an AP queue.
* @aq: pointer to the AP queue
*
* Returns AP_WAIT_NONE, AP_WAIT_AGAIN, or AP_WAIT_INTERRUPT
*/
static enum ap_wait ap_sm_read_write(struct ap_queue *aq)
{
return min(ap_sm_read(aq), ap_sm_write(aq));
}
/**
* ap_sm_reset(): Reset an AP queue.
* @qid: The AP queue number
*
* Submit the Reset command to an AP queue.
*/
static enum ap_wait ap_sm_reset(struct ap_queue *aq)
{
struct ap_queue_status status;
status = ap_rapq(aq->qid);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
case AP_RESPONSE_RESET_IN_PROGRESS:
aq->state = AP_STATE_RESET_WAIT;
aq->interrupt = AP_INTR_DISABLED;
return AP_WAIT_TIMEOUT;
case AP_RESPONSE_BUSY:
return AP_WAIT_TIMEOUT;
case AP_RESPONSE_Q_NOT_AVAIL:
case AP_RESPONSE_DECONFIGURED:
case AP_RESPONSE_CHECKSTOPPED:
default:
aq->state = AP_STATE_BORKED;
return AP_WAIT_NONE;
}
}
/**
* ap_sm_reset_wait(): Test queue for completion of the reset operation
* @aq: pointer to the AP queue
*
* Returns AP_POLL_IMMEDIATELY, AP_POLL_AFTER_TIMEROUT or 0.
*/
static enum ap_wait ap_sm_reset_wait(struct ap_queue *aq)
{
struct ap_queue_status status;
void *lsi_ptr;
if (aq->queue_count > 0 && aq->reply)
/* Try to read a completed message and get the status */
status = ap_sm_recv(aq);
else
/* Get the status with TAPQ */
status = ap_tapq(aq->qid, NULL);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
lsi_ptr = ap_airq_ptr();
if (lsi_ptr && ap_queue_enable_interruption(aq, lsi_ptr) == 0)
aq->state = AP_STATE_SETIRQ_WAIT;
else
aq->state = (aq->queue_count > 0) ?
AP_STATE_WORKING : AP_STATE_IDLE;
return AP_WAIT_AGAIN;
case AP_RESPONSE_BUSY:
case AP_RESPONSE_RESET_IN_PROGRESS:
return AP_WAIT_TIMEOUT;
case AP_RESPONSE_Q_NOT_AVAIL:
case AP_RESPONSE_DECONFIGURED:
case AP_RESPONSE_CHECKSTOPPED:
default:
aq->state = AP_STATE_BORKED;
return AP_WAIT_NONE;
}
}
/**
* ap_sm_setirq_wait(): Test queue for completion of the irq enablement
* @aq: pointer to the AP queue
*
* Returns AP_POLL_IMMEDIATELY, AP_POLL_AFTER_TIMEROUT or 0.
*/
static enum ap_wait ap_sm_setirq_wait(struct ap_queue *aq)
{
struct ap_queue_status status;
if (aq->queue_count > 0 && aq->reply)
/* Try to read a completed message and get the status */
status = ap_sm_recv(aq);
else
/* Get the status with TAPQ */
status = ap_tapq(aq->qid, NULL);
if (status.irq_enabled == 1) {
/* Irqs are now enabled */
aq->interrupt = AP_INTR_ENABLED;
aq->state = (aq->queue_count > 0) ?
AP_STATE_WORKING : AP_STATE_IDLE;
}
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
if (aq->queue_count > 0)
return AP_WAIT_AGAIN;
/* fallthrough */
case AP_RESPONSE_NO_PENDING_REPLY:
return AP_WAIT_TIMEOUT;
default:
aq->state = AP_STATE_BORKED;
return AP_WAIT_NONE;
}
}
/*
* AP state machine jump table
*/
static ap_func_t *ap_jumptable[NR_AP_STATES][NR_AP_EVENTS] = {
[AP_STATE_RESET_START] = {
[AP_EVENT_POLL] = ap_sm_reset,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
[AP_STATE_RESET_WAIT] = {
[AP_EVENT_POLL] = ap_sm_reset_wait,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
[AP_STATE_SETIRQ_WAIT] = {
[AP_EVENT_POLL] = ap_sm_setirq_wait,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
[AP_STATE_IDLE] = {
[AP_EVENT_POLL] = ap_sm_write,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
[AP_STATE_WORKING] = {
[AP_EVENT_POLL] = ap_sm_read_write,
[AP_EVENT_TIMEOUT] = ap_sm_reset,
},
[AP_STATE_QUEUE_FULL] = {
[AP_EVENT_POLL] = ap_sm_read,
[AP_EVENT_TIMEOUT] = ap_sm_reset,
},
[AP_STATE_SUSPEND_WAIT] = {
[AP_EVENT_POLL] = ap_sm_suspend_read,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
[AP_STATE_BORKED] = {
[AP_EVENT_POLL] = ap_sm_nop,
[AP_EVENT_TIMEOUT] = ap_sm_nop,
},
};
enum ap_wait ap_sm_event(struct ap_queue *aq, enum ap_event event)
{
return ap_jumptable[aq->state][event](aq);
}
enum ap_wait ap_sm_event_loop(struct ap_queue *aq, enum ap_event event)
{
enum ap_wait wait;
while ((wait = ap_sm_event(aq, event)) == AP_WAIT_AGAIN)
;
return wait;
}
/*
* Power management for queue devices
*/
void ap_queue_suspend(struct ap_device *ap_dev)
{
struct ap_queue *aq = to_ap_queue(&ap_dev->device);
/* Poll on the device until all requests are finished. */
spin_lock_bh(&aq->lock);
aq->state = AP_STATE_SUSPEND_WAIT;
while (ap_sm_event(aq, AP_EVENT_POLL) != AP_WAIT_NONE)
;
aq->state = AP_STATE_BORKED;
spin_unlock_bh(&aq->lock);
}
EXPORT_SYMBOL(ap_queue_suspend);
void ap_queue_resume(struct ap_device *ap_dev)
{
}
EXPORT_SYMBOL(ap_queue_resume);
/*
* AP queue related attributes.
*/
static ssize_t ap_req_count_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ap_queue *aq = to_ap_queue(dev);
unsigned int req_cnt;
spin_lock_bh(&aq->lock);
req_cnt = aq->total_request_count;
spin_unlock_bh(&aq->lock);
return snprintf(buf, PAGE_SIZE, "%d\n", req_cnt);
}
static ssize_t ap_req_count_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ap_queue *aq = to_ap_queue(dev);
spin_lock_bh(&aq->lock);
aq->total_request_count = 0;
spin_unlock_bh(&aq->lock);
return count;
}
static DEVICE_ATTR(request_count, 0644, ap_req_count_show, ap_req_count_store);
static ssize_t ap_requestq_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ap_queue *aq = to_ap_queue(dev);
unsigned int reqq_cnt = 0;
spin_lock_bh(&aq->lock);
reqq_cnt = aq->requestq_count;
spin_unlock_bh(&aq->lock);
return snprintf(buf, PAGE_SIZE, "%d\n", reqq_cnt);
}
static DEVICE_ATTR(requestq_count, 0444, ap_requestq_count_show, NULL);
static ssize_t ap_pendingq_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ap_queue *aq = to_ap_queue(dev);
unsigned int penq_cnt = 0;
spin_lock_bh(&aq->lock);
penq_cnt = aq->pendingq_count;
spin_unlock_bh(&aq->lock);
return snprintf(buf, PAGE_SIZE, "%d\n", penq_cnt);
}
static DEVICE_ATTR(pendingq_count, 0444, ap_pendingq_count_show, NULL);
static ssize_t ap_reset_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ap_queue *aq = to_ap_queue(dev);
int rc = 0;
spin_lock_bh(&aq->lock);
switch (aq->state) {
case AP_STATE_RESET_START:
case AP_STATE_RESET_WAIT:
rc = snprintf(buf, PAGE_SIZE, "Reset in progress.\n");
break;
case AP_STATE_WORKING:
case AP_STATE_QUEUE_FULL:
rc = snprintf(buf, PAGE_SIZE, "Reset Timer armed.\n");
break;
default:
rc = snprintf(buf, PAGE_SIZE, "No Reset Timer set.\n");
}
spin_unlock_bh(&aq->lock);
return rc;
}
static DEVICE_ATTR(reset, 0444, ap_reset_show, NULL);
static ssize_t ap_interrupt_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ap_queue *aq = to_ap_queue(dev);
int rc = 0;
spin_lock_bh(&aq->lock);
if (aq->state == AP_STATE_SETIRQ_WAIT)
rc = snprintf(buf, PAGE_SIZE, "Enable Interrupt pending.\n");
else if (aq->interrupt == AP_INTR_ENABLED)
rc = snprintf(buf, PAGE_SIZE, "Interrupts enabled.\n");
else
rc = snprintf(buf, PAGE_SIZE, "Interrupts disabled.\n");
spin_unlock_bh(&aq->lock);
return rc;
}
static DEVICE_ATTR(interrupt, 0444, ap_interrupt_show, NULL);
static struct attribute *ap_queue_dev_attrs[] = {
&dev_attr_request_count.attr,
&dev_attr_requestq_count.attr,
&dev_attr_pendingq_count.attr,
&dev_attr_reset.attr,
&dev_attr_interrupt.attr,
NULL
};
static struct attribute_group ap_queue_dev_attr_group = {
.attrs = ap_queue_dev_attrs
};
static const struct attribute_group *ap_queue_dev_attr_groups[] = {
&ap_queue_dev_attr_group,
NULL
};
static struct device_type ap_queue_type = {
.name = "ap_queue",
.groups = ap_queue_dev_attr_groups,
};
static void ap_queue_device_release(struct device *dev)
{
struct ap_queue *aq = to_ap_queue(dev);
if (!list_empty(&aq->list)) {
spin_lock_bh(&ap_list_lock);
list_del_init(&aq->list);
spin_unlock_bh(&ap_list_lock);
}
kfree(aq);
}
struct ap_queue *ap_queue_create(ap_qid_t qid, int device_type)
{
struct ap_queue *aq;
aq = kzalloc(sizeof(*aq), GFP_KERNEL);
if (!aq)
return NULL;
aq->ap_dev.device.release = ap_queue_device_release;
aq->ap_dev.device.type = &ap_queue_type;
aq->ap_dev.device_type = device_type;
/* CEX6 toleration: map to CEX5 */
if (device_type == AP_DEVICE_TYPE_CEX6)
aq->ap_dev.device_type = AP_DEVICE_TYPE_CEX5;
aq->qid = qid;
aq->state = AP_STATE_RESET_START;
aq->interrupt = AP_INTR_DISABLED;
spin_lock_init(&aq->lock);
INIT_LIST_HEAD(&aq->pendingq);
INIT_LIST_HEAD(&aq->requestq);
setup_timer(&aq->timeout, ap_request_timeout, (unsigned long) aq);
return aq;
}
void ap_queue_init_reply(struct ap_queue *aq, struct ap_message *reply)
{
aq->reply = reply;
spin_lock_bh(&aq->lock);
ap_wait(ap_sm_event(aq, AP_EVENT_POLL));
spin_unlock_bh(&aq->lock);
}
EXPORT_SYMBOL(ap_queue_init_reply);
/**
* ap_queue_message(): Queue a request to an AP device.
* @aq: The AP device to queue the message to
* @ap_msg: The message that is to be added
*/
void ap_queue_message(struct ap_queue *aq, struct ap_message *ap_msg)
{
/* For asynchronous message handling a valid receive-callback
* is required.
*/
BUG_ON(!ap_msg->receive);
spin_lock_bh(&aq->lock);
/* Queue the message. */
list_add_tail(&ap_msg->list, &aq->requestq);
aq->requestq_count++;
aq->total_request_count++;
atomic_inc(&aq->card->total_request_count);
/* Send/receive as many request from the queue as possible. */
ap_wait(ap_sm_event_loop(aq, AP_EVENT_POLL));
spin_unlock_bh(&aq->lock);
}
EXPORT_SYMBOL(ap_queue_message);
/**
* ap_cancel_message(): Cancel a crypto request.
* @aq: The AP device that has the message queued
* @ap_msg: The message that is to be removed
*
* Cancel a crypto request. This is done by removing the request
* from the device pending or request queue. Note that the
* request stays on the AP queue. When it finishes the message
* reply will be discarded because the psmid can't be found.
*/
void ap_cancel_message(struct ap_queue *aq, struct ap_message *ap_msg)
{
struct ap_message *tmp;
spin_lock_bh(&aq->lock);
if (!list_empty(&ap_msg->list)) {
list_for_each_entry(tmp, &aq->pendingq, list)
if (tmp->psmid == ap_msg->psmid) {
aq->pendingq_count--;
goto found;
}
aq->requestq_count--;
found:
list_del_init(&ap_msg->list);
}
spin_unlock_bh(&aq->lock);
}
EXPORT_SYMBOL(ap_cancel_message);
/**
* __ap_flush_queue(): Flush requests.
* @aq: Pointer to the AP queue
*
* Flush all requests from the request/pending queue of an AP device.
*/
static void __ap_flush_queue(struct ap_queue *aq)
{
struct ap_message *ap_msg, *next;
list_for_each_entry_safe(ap_msg, next, &aq->pendingq, list) {
list_del_init(&ap_msg->list);
aq->pendingq_count--;
ap_msg->rc = -EAGAIN;
ap_msg->receive(aq, ap_msg, NULL);
}
list_for_each_entry_safe(ap_msg, next, &aq->requestq, list) {
list_del_init(&ap_msg->list);
aq->requestq_count--;
ap_msg->rc = -EAGAIN;
ap_msg->receive(aq, ap_msg, NULL);
}
}
void ap_flush_queue(struct ap_queue *aq)
{
spin_lock_bh(&aq->lock);
__ap_flush_queue(aq);
spin_unlock_bh(&aq->lock);
}
EXPORT_SYMBOL(ap_flush_queue);
void ap_queue_remove(struct ap_queue *aq)
{
ap_flush_queue(aq);
del_timer_sync(&aq->timeout);
}
EXPORT_SYMBOL(ap_queue_remove);