Linux-2.6.33.2/drivers/s390/crypto/ap_bus.c
/*
* linux/drivers/s390/crypto/ap_bus.c
*
* Copyright (C) 2006 IBM Corporation
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Ralph Wuerthner <rwuerthn@de.ibm.com>
* Felix Beck <felix.beck@de.ibm.com>
*
* Adjunct processor bus.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#define KMSG_COMPONENT "ap"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/notifier.h>
#include <linux/kthread.h>
#include <linux/mutex.h>
#include <asm/reset.h>
#include <asm/airq.h>
#include <asm/atomic.h>
#include <asm/system.h>
#include <asm/isc.h>
#include <linux/hrtimer.h>
#include <linux/ktime.h>
#include "ap_bus.h"
/* Some prototypes. */
static void ap_scan_bus(struct work_struct *);
static void ap_poll_all(unsigned long);
static enum hrtimer_restart ap_poll_timeout(struct hrtimer *);
static int ap_poll_thread_start(void);
static void ap_poll_thread_stop(void);
static void ap_request_timeout(unsigned long);
static inline void ap_schedule_poll_timer(void);
static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags);
static int ap_device_remove(struct device *dev);
static int ap_device_probe(struct device *dev);
static void ap_interrupt_handler(void *unused1, void *unused2);
static void ap_reset(struct ap_device *ap_dev);
static void ap_config_timeout(unsigned long ptr);
static int ap_select_domain(void);
/*
* Module description.
*/
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("Adjunct Processor Bus driver, "
"Copyright 2006 IBM Corporation");
MODULE_LICENSE("GPL");
/*
* Module parameter
*/
int ap_domain_index = -1; /* Adjunct Processor Domain Index */
module_param_named(domain, ap_domain_index, int, 0000);
MODULE_PARM_DESC(domain, "domain index for ap devices");
EXPORT_SYMBOL(ap_domain_index);
static int ap_thread_flag = 0;
module_param_named(poll_thread, ap_thread_flag, int, 0000);
MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off).");
static struct device *ap_root_device = NULL;
static DEFINE_SPINLOCK(ap_device_list_lock);
static LIST_HEAD(ap_device_list);
/*
* Workqueue & timer for bus rescan.
*/
static struct workqueue_struct *ap_work_queue;
static struct timer_list ap_config_timer;
static int ap_config_time = AP_CONFIG_TIME;
static DECLARE_WORK(ap_config_work, ap_scan_bus);
/*
* Tasklet & timer for AP request polling and interrupts
*/
static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0);
static atomic_t ap_poll_requests = ATOMIC_INIT(0);
static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
static struct task_struct *ap_poll_kthread = NULL;
static DEFINE_MUTEX(ap_poll_thread_mutex);
static DEFINE_SPINLOCK(ap_poll_timer_lock);
static void *ap_interrupt_indicator;
static struct hrtimer ap_poll_timer;
/* In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
* If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.*/
static unsigned long long poll_timeout = 250000;
/* Suspend flag */
static int ap_suspend_flag;
/* Flag to check if domain was set through module parameter domain=. This is
* important when supsend and resume is done in a z/VM environment where the
* domain might change. */
static int user_set_domain = 0;
static struct bus_type ap_bus_type;
/**
* ap_using_interrupts() - Returns non-zero if interrupt support is
* available.
*/
static inline int ap_using_interrupts(void)
{
return ap_interrupt_indicator != NULL;
}
/**
* ap_intructions_available() - Test if AP instructions are available.
*
* Returns 0 if the AP instructions are installed.
*/
static inline int ap_instructions_available(void)
{
register unsigned long reg0 asm ("0") = AP_MKQID(0,0);
register unsigned long reg1 asm ("1") = -ENODEV;
register unsigned long reg2 asm ("2") = 0UL;
asm volatile(
" .long 0xb2af0000\n" /* PQAP(TAPQ) */
"0: la %1,0\n"
"1:\n"
EX_TABLE(0b, 1b)
: "+d" (reg0), "+d" (reg1), "+d" (reg2) : : "cc" );
return reg1;
}
/**
* ap_interrupts_available(): Test if AP interrupts are available.
*
* Returns 1 if AP interrupts are available.
*/
static int ap_interrupts_available(void)
{
unsigned long long facility_bits[2];
if (stfle(facility_bits, 2) <= 1)
return 0;
if (!(facility_bits[0] & (1ULL << 61)) ||
!(facility_bits[1] & (1ULL << 62)))
return 0;
return 1;
}
/**
* ap_test_queue(): Test adjunct processor queue.
* @qid: The AP queue number
* @queue_depth: Pointer to queue depth value
* @device_type: Pointer to device type value
*
* Returns AP queue status structure.
*/
static inline struct ap_queue_status
ap_test_queue(ap_qid_t qid, int *queue_depth, int *device_type)
{
register unsigned long reg0 asm ("0") = qid;
register struct ap_queue_status reg1 asm ("1");
register unsigned long reg2 asm ("2") = 0UL;
asm volatile(".long 0xb2af0000" /* PQAP(TAPQ) */
: "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc");
*device_type = (int) (reg2 >> 24);
*queue_depth = (int) (reg2 & 0xff);
return reg1;
}
/**
* ap_reset_queue(): Reset adjunct processor queue.
* @qid: The AP queue number
*
* Returns AP queue status structure.
*/
static inline struct ap_queue_status ap_reset_queue(ap_qid_t qid)
{
register unsigned long reg0 asm ("0") = qid | 0x01000000UL;
register struct ap_queue_status reg1 asm ("1");
register unsigned long reg2 asm ("2") = 0UL;
asm volatile(
".long 0xb2af0000" /* PQAP(RAPQ) */
: "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc");
return reg1;
}
#ifdef CONFIG_64BIT
/**
* ap_queue_interruption_control(): Enable interruption for a specific AP.
* @qid: The AP queue number
* @ind: The notification indicator byte
*
* Returns AP queue status.
*/
static inline struct ap_queue_status
ap_queue_interruption_control(ap_qid_t qid, void *ind)
{
register unsigned long reg0 asm ("0") = qid | 0x03000000UL;
register unsigned long reg1_in asm ("1") = 0x0000800000000000UL | AP_ISC;
register struct ap_queue_status reg1_out asm ("1");
register void *reg2 asm ("2") = ind;
asm volatile(
".long 0xb2af0000" /* PQAP(RAPQ) */
: "+d" (reg0), "+d" (reg1_in), "=d" (reg1_out), "+d" (reg2)
:
: "cc" );
return reg1_out;
}
#endif
/**
* ap_queue_enable_interruption(): Enable interruption on an AP.
* @qid: The AP queue number
* @ind: the notification indicator byte
*
* Enables interruption on AP queue via ap_queue_interruption_control(). 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(ap_qid_t qid, void *ind)
{
#ifdef CONFIG_64BIT
struct ap_queue_status status;
int t_depth, t_device_type, rc, i;
rc = -EBUSY;
status = ap_queue_interruption_control(qid, ind);
for (i = 0; i < AP_MAX_RESET; i++) {
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
if (status.int_enabled)
return 0;
break;
case AP_RESPONSE_RESET_IN_PROGRESS:
case AP_RESPONSE_BUSY:
break;
case AP_RESPONSE_Q_NOT_AVAIL:
case AP_RESPONSE_DECONFIGURED:
case AP_RESPONSE_CHECKSTOPPED:
case AP_RESPONSE_INVALID_ADDRESS:
return -ENODEV;
case AP_RESPONSE_OTHERWISE_CHANGED:
if (status.int_enabled)
return 0;
break;
default:
break;
}
if (i < AP_MAX_RESET - 1) {
udelay(5);
status = ap_test_queue(qid, &t_depth, &t_device_type);
}
}
return rc;
#else
return -EINVAL;
#endif
}
/**
* __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)
{
typedef struct { char _[length]; } msgblock;
register unsigned long reg0 asm ("0") = qid | 0x40000000UL;
register struct ap_queue_status reg1 asm ("1");
register unsigned long reg2 asm ("2") = (unsigned long) msg;
register unsigned long reg3 asm ("3") = (unsigned long) length;
register unsigned long reg4 asm ("4") = (unsigned int) (psmid >> 32);
register unsigned long reg5 asm ("5") = (unsigned int) psmid;
if (special == 1)
reg0 |= 0x400000UL;
asm volatile (
"0: .long 0xb2ad0042\n" /* DQAP */
" brc 2,0b"
: "+d" (reg0), "=d" (reg1), "+d" (reg2), "+d" (reg3)
: "d" (reg4), "d" (reg5), "m" (*(msgblock *) msg)
: "cc" );
return reg1;
}
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);
/**
* __ap_recv(): Receive message from adjunct processor queue.
* @qid: The AP queue number
* @psmid: Pointer to program supplied message identifier
* @msg: The message text
* @length: The message length
*
* Returns AP queue status structure.
* Condition code 1 on DQAP means the receive has taken place
* but only partially. The response is incomplete, hence the
* DQAP is repeated.
* Condition code 2 on DQAP also means the receive is incomplete,
* this time because a segment boundary was reached. Again, the
* DQAP is repeated.
* Note that gpr2 is used by the DQAP instruction to keep track of
* any 'residual' length, in case the instruction gets interrupted.
* Hence it gets zeroed before the instruction.
*/
static inline struct ap_queue_status
__ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length)
{
typedef struct { char _[length]; } msgblock;
register unsigned long reg0 asm("0") = qid | 0x80000000UL;
register struct ap_queue_status reg1 asm ("1");
register unsigned long reg2 asm("2") = 0UL;
register unsigned long reg4 asm("4") = (unsigned long) msg;
register unsigned long reg5 asm("5") = (unsigned long) length;
register unsigned long reg6 asm("6") = 0UL;
register unsigned long reg7 asm("7") = 0UL;
asm volatile(
"0: .long 0xb2ae0064\n"
" brc 6,0b\n"
: "+d" (reg0), "=d" (reg1), "+d" (reg2),
"+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7),
"=m" (*(msgblock *) msg) : : "cc" );
*psmid = (((unsigned long long) reg6) << 32) + reg7;
return reg1;
}
int ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length)
{
struct ap_queue_status status;
status = __ap_recv(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);
/**
* ap_query_queue(): Check if an AP queue is available.
* @qid: The AP queue number
* @queue_depth: Pointer to queue depth value
* @device_type: Pointer to device type value
*
* The test is repeated for AP_MAX_RESET times.
*/
static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type)
{
struct ap_queue_status status;
int t_depth, t_device_type, rc, i;
rc = -EBUSY;
for (i = 0; i < AP_MAX_RESET; i++) {
status = ap_test_queue(qid, &t_depth, &t_device_type);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
*queue_depth = t_depth + 1;
*device_type = t_device_type;
rc = 0;
break;
case AP_RESPONSE_Q_NOT_AVAIL:
rc = -ENODEV;
break;
case AP_RESPONSE_RESET_IN_PROGRESS:
break;
case AP_RESPONSE_DECONFIGURED:
rc = -ENODEV;
break;
case AP_RESPONSE_CHECKSTOPPED:
rc = -ENODEV;
break;
case AP_RESPONSE_INVALID_ADDRESS:
rc = -ENODEV;
break;
case AP_RESPONSE_OTHERWISE_CHANGED:
break;
case AP_RESPONSE_BUSY:
break;
default:
BUG();
}
if (rc != -EBUSY)
break;
if (i < AP_MAX_RESET - 1)
udelay(5);
}
return rc;
}
/**
* ap_init_queue(): Reset an AP queue.
* @qid: The AP queue number
*
* Reset an AP queue and wait for it to become available again.
*/
static int ap_init_queue(ap_qid_t qid)
{
struct ap_queue_status status;
int rc, dummy, i;
rc = -ENODEV;
status = ap_reset_queue(qid);
for (i = 0; i < AP_MAX_RESET; i++) {
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
if (status.queue_empty)
rc = 0;
break;
case AP_RESPONSE_Q_NOT_AVAIL:
case AP_RESPONSE_DECONFIGURED:
case AP_RESPONSE_CHECKSTOPPED:
i = AP_MAX_RESET; /* return with -ENODEV */
break;
case AP_RESPONSE_RESET_IN_PROGRESS:
rc = -EBUSY;
case AP_RESPONSE_BUSY:
default:
break;
}
if (rc != -ENODEV && rc != -EBUSY)
break;
if (i < AP_MAX_RESET - 1) {
udelay(5);
status = ap_test_queue(qid, &dummy, &dummy);
}
}
if (rc == 0 && ap_using_interrupts()) {
rc = ap_queue_enable_interruption(qid, ap_interrupt_indicator);
/* If interruption mode is supported by the machine,
* but an AP can not be enabled for interruption then
* the AP will be discarded. */
if (rc)
pr_err("Registering adapter interrupts for "
"AP %d failed\n", AP_QID_DEVICE(qid));
}
return rc;
}
/**
* ap_increase_queue_count(): Arm request timeout.
* @ap_dev: Pointer to an AP device.
*
* Arm request timeout if an AP device was idle and a new request is submitted.
*/
static void ap_increase_queue_count(struct ap_device *ap_dev)
{
int timeout = ap_dev->drv->request_timeout;
ap_dev->queue_count++;
if (ap_dev->queue_count == 1) {
mod_timer(&ap_dev->timeout, jiffies + timeout);
ap_dev->reset = AP_RESET_ARMED;
}
}
/**
* ap_decrease_queue_count(): Decrease queue count.
* @ap_dev: Pointer to an AP device.
*
* If AP device is still alive, re-schedule request timeout if there are still
* pending requests.
*/
static void ap_decrease_queue_count(struct ap_device *ap_dev)
{
int timeout = ap_dev->drv->request_timeout;
ap_dev->queue_count--;
if (ap_dev->queue_count > 0)
mod_timer(&ap_dev->timeout, jiffies + timeout);
else
/*
* The timeout timer should to be disabled now - since
* del_timer_sync() is very expensive, we just tell via the
* reset flag to ignore the pending timeout timer.
*/
ap_dev->reset = AP_RESET_IGNORE;
}
/*
* AP device related attributes.
*/
static ssize_t ap_hwtype_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ap_device *ap_dev = to_ap_dev(dev);
return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->device_type);
}
static DEVICE_ATTR(hwtype, 0444, ap_hwtype_show, NULL);
static ssize_t ap_depth_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct ap_device *ap_dev = to_ap_dev(dev);
return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->queue_depth);
}
static DEVICE_ATTR(depth, 0444, ap_depth_show, NULL);
static ssize_t ap_request_count_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct ap_device *ap_dev = to_ap_dev(dev);
int rc;
spin_lock_bh(&ap_dev->lock);
rc = snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->total_request_count);
spin_unlock_bh(&ap_dev->lock);
return rc;
}
static DEVICE_ATTR(request_count, 0444, ap_request_count_show, NULL);
static ssize_t ap_modalias_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "ap:t%02X", to_ap_dev(dev)->device_type);
}
static DEVICE_ATTR(modalias, 0444, ap_modalias_show, NULL);
static struct attribute *ap_dev_attrs[] = {
&dev_attr_hwtype.attr,
&dev_attr_depth.attr,
&dev_attr_request_count.attr,
&dev_attr_modalias.attr,
NULL
};
static struct attribute_group ap_dev_attr_group = {
.attrs = ap_dev_attrs
};
/**
* ap_bus_match()
* @dev: Pointer to device
* @drv: Pointer to device_driver
*
* AP bus driver registration/unregistration.
*/
static int ap_bus_match(struct device *dev, struct device_driver *drv)
{
struct ap_device *ap_dev = to_ap_dev(dev);
struct ap_driver *ap_drv = to_ap_drv(drv);
struct ap_device_id *id;
/*
* Compare device type of the device with the list of
* supported types of the device_driver.
*/
for (id = ap_drv->ids; id->match_flags; id++) {
if ((id->match_flags & AP_DEVICE_ID_MATCH_DEVICE_TYPE) &&
(id->dev_type != ap_dev->device_type))
continue;
return 1;
}
return 0;
}
/**
* ap_uevent(): Uevent function for AP devices.
* @dev: Pointer to device
* @env: Pointer to kobj_uevent_env
*
* It sets up a single environment variable DEV_TYPE which contains the
* hardware device type.
*/
static int ap_uevent (struct device *dev, struct kobj_uevent_env *env)
{
struct ap_device *ap_dev = to_ap_dev(dev);
int retval = 0;
if (!ap_dev)
return -ENODEV;
/* Set up DEV_TYPE environment variable. */
retval = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
if (retval)
return retval;
/* Add MODALIAS= */
retval = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
return retval;
}
static int ap_bus_suspend(struct device *dev, pm_message_t state)
{
struct ap_device *ap_dev = to_ap_dev(dev);
unsigned long flags;
if (!ap_suspend_flag) {
ap_suspend_flag = 1;
/* Disable scanning for devices, thus we do not want to scan
* for them after removing.
*/
del_timer_sync(&ap_config_timer);
if (ap_work_queue != NULL) {
destroy_workqueue(ap_work_queue);
ap_work_queue = NULL;
}
tasklet_disable(&ap_tasklet);
}
/* Poll on the device until all requests are finished. */
do {
flags = 0;
spin_lock_bh(&ap_dev->lock);
__ap_poll_device(ap_dev, &flags);
spin_unlock_bh(&ap_dev->lock);
} while ((flags & 1) || (flags & 2));
spin_lock_bh(&ap_dev->lock);
ap_dev->unregistered = 1;
spin_unlock_bh(&ap_dev->lock);
return 0;
}
static int ap_bus_resume(struct device *dev)
{
int rc = 0;
struct ap_device *ap_dev = to_ap_dev(dev);
if (ap_suspend_flag) {
ap_suspend_flag = 0;
if (!ap_interrupts_available())
ap_interrupt_indicator = NULL;
if (!user_set_domain) {
ap_domain_index = -1;
ap_select_domain();
}
init_timer(&ap_config_timer);
ap_config_timer.function = ap_config_timeout;
ap_config_timer.data = 0;
ap_config_timer.expires = jiffies + ap_config_time * HZ;
add_timer(&ap_config_timer);
ap_work_queue = create_singlethread_workqueue("kapwork");
if (!ap_work_queue)
return -ENOMEM;
tasklet_enable(&ap_tasklet);
if (!ap_using_interrupts())
ap_schedule_poll_timer();
else
tasklet_schedule(&ap_tasklet);
if (ap_thread_flag)
rc = ap_poll_thread_start();
}
if (AP_QID_QUEUE(ap_dev->qid) != ap_domain_index) {
spin_lock_bh(&ap_dev->lock);
ap_dev->qid = AP_MKQID(AP_QID_DEVICE(ap_dev->qid),
ap_domain_index);
spin_unlock_bh(&ap_dev->lock);
}
queue_work(ap_work_queue, &ap_config_work);
return rc;
}
static struct bus_type ap_bus_type = {
.name = "ap",
.match = &ap_bus_match,
.uevent = &ap_uevent,
.suspend = ap_bus_suspend,
.resume = ap_bus_resume
};
static int ap_device_probe(struct device *dev)
{
struct ap_device *ap_dev = to_ap_dev(dev);
struct ap_driver *ap_drv = to_ap_drv(dev->driver);
int rc;
ap_dev->drv = ap_drv;
rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
if (!rc) {
spin_lock_bh(&ap_device_list_lock);
list_add(&ap_dev->list, &ap_device_list);
spin_unlock_bh(&ap_device_list_lock);
}
return rc;
}
/**
* __ap_flush_queue(): Flush requests.
* @ap_dev: Pointer to the AP device
*
* Flush all requests from the request/pending queue of an AP device.
*/
static void __ap_flush_queue(struct ap_device *ap_dev)
{
struct ap_message *ap_msg, *next;
list_for_each_entry_safe(ap_msg, next, &ap_dev->pendingq, list) {
list_del_init(&ap_msg->list);
ap_dev->pendingq_count--;
ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
}
list_for_each_entry_safe(ap_msg, next, &ap_dev->requestq, list) {
list_del_init(&ap_msg->list);
ap_dev->requestq_count--;
ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
}
}
void ap_flush_queue(struct ap_device *ap_dev)
{
spin_lock_bh(&ap_dev->lock);
__ap_flush_queue(ap_dev);
spin_unlock_bh(&ap_dev->lock);
}
EXPORT_SYMBOL(ap_flush_queue);
static int ap_device_remove(struct device *dev)
{
struct ap_device *ap_dev = to_ap_dev(dev);
struct ap_driver *ap_drv = ap_dev->drv;
ap_flush_queue(ap_dev);
del_timer_sync(&ap_dev->timeout);
spin_lock_bh(&ap_device_list_lock);
list_del_init(&ap_dev->list);
spin_unlock_bh(&ap_device_list_lock);
if (ap_drv->remove)
ap_drv->remove(ap_dev);
spin_lock_bh(&ap_dev->lock);
atomic_sub(ap_dev->queue_count, &ap_poll_requests);
spin_unlock_bh(&ap_dev->lock);
return 0;
}
int ap_driver_register(struct ap_driver *ap_drv, struct module *owner,
char *name)
{
struct device_driver *drv = &ap_drv->driver;
drv->bus = &ap_bus_type;
drv->probe = ap_device_probe;
drv->remove = ap_device_remove;
drv->owner = owner;
drv->name = name;
return driver_register(drv);
}
EXPORT_SYMBOL(ap_driver_register);
void ap_driver_unregister(struct ap_driver *ap_drv)
{
driver_unregister(&ap_drv->driver);
}
EXPORT_SYMBOL(ap_driver_unregister);
/*
* AP bus attributes.
*/
static ssize_t ap_domain_show(struct bus_type *bus, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", ap_domain_index);
}
static BUS_ATTR(ap_domain, 0444, ap_domain_show, NULL);
static ssize_t ap_config_time_show(struct bus_type *bus, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time);
}
static ssize_t ap_interrupts_show(struct bus_type *bus, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n",
ap_using_interrupts() ? 1 : 0);
}
static BUS_ATTR(ap_interrupts, 0444, ap_interrupts_show, NULL);
static ssize_t ap_config_time_store(struct bus_type *bus,
const char *buf, size_t count)
{
int time;
if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120)
return -EINVAL;
ap_config_time = time;
if (!timer_pending(&ap_config_timer) ||
!mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ)) {
ap_config_timer.expires = jiffies + ap_config_time * HZ;
add_timer(&ap_config_timer);
}
return count;
}
static BUS_ATTR(config_time, 0644, ap_config_time_show, ap_config_time_store);
static ssize_t ap_poll_thread_show(struct bus_type *bus, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%d\n", ap_poll_kthread ? 1 : 0);
}
static ssize_t ap_poll_thread_store(struct bus_type *bus,
const char *buf, size_t count)
{
int flag, rc;
if (sscanf(buf, "%d\n", &flag) != 1)
return -EINVAL;
if (flag) {
rc = ap_poll_thread_start();
if (rc)
return rc;
}
else
ap_poll_thread_stop();
return count;
}
static BUS_ATTR(poll_thread, 0644, ap_poll_thread_show, ap_poll_thread_store);
static ssize_t poll_timeout_show(struct bus_type *bus, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%llu\n", poll_timeout);
}
static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf,
size_t count)
{
unsigned long long time;
ktime_t hr_time;
/* 120 seconds = maximum poll interval */
if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 ||
time > 120000000000ULL)
return -EINVAL;
poll_timeout = time;
hr_time = ktime_set(0, poll_timeout);
if (!hrtimer_is_queued(&ap_poll_timer) ||
!hrtimer_forward(&ap_poll_timer, hrtimer_get_expires(&ap_poll_timer), hr_time)) {
hrtimer_set_expires(&ap_poll_timer, hr_time);
hrtimer_start_expires(&ap_poll_timer, HRTIMER_MODE_ABS);
}
return count;
}
static BUS_ATTR(poll_timeout, 0644, poll_timeout_show, poll_timeout_store);
static struct bus_attribute *const ap_bus_attrs[] = {
&bus_attr_ap_domain,
&bus_attr_config_time,
&bus_attr_poll_thread,
&bus_attr_ap_interrupts,
&bus_attr_poll_timeout,
NULL,
};
/**
* ap_select_domain(): Select an AP domain.
*
* Pick one of the 16 AP domains.
*/
static int ap_select_domain(void)
{
int queue_depth, device_type, count, max_count, best_domain;
int rc, i, j;
/*
* We want to use a single domain. Either the one specified with
* the "domain=" parameter or the domain with the maximum number
* of devices.
*/
if (ap_domain_index >= 0 && ap_domain_index < AP_DOMAINS)
/* Domain has already been selected. */
return 0;
best_domain = -1;
max_count = 0;
for (i = 0; i < AP_DOMAINS; i++) {
count = 0;
for (j = 0; j < AP_DEVICES; j++) {
ap_qid_t qid = AP_MKQID(j, i);
rc = ap_query_queue(qid, &queue_depth, &device_type);
if (rc)
continue;
count++;
}
if (count > max_count) {
max_count = count;
best_domain = i;
}
}
if (best_domain >= 0){
ap_domain_index = best_domain;
return 0;
}
return -ENODEV;
}
/**
* ap_probe_device_type(): Find the device type of an AP.
* @ap_dev: pointer to the AP device.
*
* Find the device type if query queue returned a device type of 0.
*/
static int ap_probe_device_type(struct ap_device *ap_dev)
{
static unsigned char msg[] = {
0x00,0x06,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x58,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x01,0x00,0x43,0x43,0x41,0x2d,0x41,0x50,
0x50,0x4c,0x20,0x20,0x20,0x01,0x01,0x01,
0x00,0x00,0x00,0x00,0x50,0x4b,0x00,0x00,
0x00,0x00,0x01,0x1c,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x05,0xb8,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x70,0x00,0x41,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x54,0x32,0x01,0x00,0xa0,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0xb8,0x05,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x0a,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00,
0x49,0x43,0x53,0x46,0x20,0x20,0x20,0x20,
0x50,0x4b,0x0a,0x00,0x50,0x4b,0x43,0x53,
0x2d,0x31,0x2e,0x32,0x37,0x00,0x11,0x22,
0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
0x11,0x22,0x33,0x44,0x55,0x66,0x77,0x88,
0x99,0x00,0x11,0x22,0x33,0x44,0x55,0x66,
0x77,0x88,0x99,0x00,0x11,0x22,0x33,0x44,
0x55,0x66,0x77,0x88,0x99,0x00,0x11,0x22,
0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,
0x11,0x22,0x33,0x5d,0x00,0x5b,0x00,0x77,
0x88,0x1e,0x00,0x00,0x57,0x00,0x00,0x00,
0x00,0x04,0x00,0x00,0x4f,0x00,0x00,0x00,
0x03,0x02,0x00,0x00,0x40,0x01,0x00,0x01,
0xce,0x02,0x68,0x2d,0x5f,0xa9,0xde,0x0c,
0xf6,0xd2,0x7b,0x58,0x4b,0xf9,0x28,0x68,
0x3d,0xb4,0xf4,0xef,0x78,0xd5,0xbe,0x66,
0x63,0x42,0xef,0xf8,0xfd,0xa4,0xf8,0xb0,
0x8e,0x29,0xc2,0xc9,0x2e,0xd8,0x45,0xb8,
0x53,0x8c,0x6f,0x4e,0x72,0x8f,0x6c,0x04,
0x9c,0x88,0xfc,0x1e,0xc5,0x83,0x55,0x57,
0xf7,0xdd,0xfd,0x4f,0x11,0x36,0x95,0x5d,
};
struct ap_queue_status status;
unsigned long long psmid;
char *reply;
int rc, i;
reply = (void *) get_zeroed_page(GFP_KERNEL);
if (!reply) {
rc = -ENOMEM;
goto out;
}
status = __ap_send(ap_dev->qid, 0x0102030405060708ULL,
msg, sizeof(msg), 0);
if (status.response_code != AP_RESPONSE_NORMAL) {
rc = -ENODEV;
goto out_free;
}
/* Wait for the test message to complete. */
for (i = 0; i < 6; i++) {
mdelay(300);
status = __ap_recv(ap_dev->qid, &psmid, reply, 4096);
if (status.response_code == AP_RESPONSE_NORMAL &&
psmid == 0x0102030405060708ULL)
break;
}
if (i < 6) {
/* Got an answer. */
if (reply[0] == 0x00 && reply[1] == 0x86)
ap_dev->device_type = AP_DEVICE_TYPE_PCICC;
else
ap_dev->device_type = AP_DEVICE_TYPE_PCICA;
rc = 0;
} else
rc = -ENODEV;
out_free:
free_page((unsigned long) reply);
out:
return rc;
}
static void ap_interrupt_handler(void *unused1, void *unused2)
{
tasklet_schedule(&ap_tasklet);
}
/**
* __ap_scan_bus(): Scan the AP bus.
* @dev: Pointer to device
* @data: Pointer to data
*
* Scan the AP bus for new devices.
*/
static int __ap_scan_bus(struct device *dev, void *data)
{
return to_ap_dev(dev)->qid == (ap_qid_t)(unsigned long) data;
}
static void ap_device_release(struct device *dev)
{
struct ap_device *ap_dev = to_ap_dev(dev);
kfree(ap_dev);
}
static void ap_scan_bus(struct work_struct *unused)
{
struct ap_device *ap_dev;
struct device *dev;
ap_qid_t qid;
int queue_depth, device_type;
int rc, i;
if (ap_select_domain() != 0)
return;
for (i = 0; i < AP_DEVICES; i++) {
qid = AP_MKQID(i, ap_domain_index);
dev = bus_find_device(&ap_bus_type, NULL,
(void *)(unsigned long)qid,
__ap_scan_bus);
rc = ap_query_queue(qid, &queue_depth, &device_type);
if (dev) {
if (rc == -EBUSY) {
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(AP_RESET_TIMEOUT);
rc = ap_query_queue(qid, &queue_depth,
&device_type);
}
ap_dev = to_ap_dev(dev);
spin_lock_bh(&ap_dev->lock);
if (rc || ap_dev->unregistered) {
spin_unlock_bh(&ap_dev->lock);
if (ap_dev->unregistered)
i--;
device_unregister(dev);
put_device(dev);
continue;
}
spin_unlock_bh(&ap_dev->lock);
put_device(dev);
continue;
}
if (rc)
continue;
rc = ap_init_queue(qid);
if (rc)
continue;
ap_dev = kzalloc(sizeof(*ap_dev), GFP_KERNEL);
if (!ap_dev)
break;
ap_dev->qid = qid;
ap_dev->queue_depth = queue_depth;
ap_dev->unregistered = 1;
spin_lock_init(&ap_dev->lock);
INIT_LIST_HEAD(&ap_dev->pendingq);
INIT_LIST_HEAD(&ap_dev->requestq);
INIT_LIST_HEAD(&ap_dev->list);
setup_timer(&ap_dev->timeout, ap_request_timeout,
(unsigned long) ap_dev);
if (device_type == 0)
ap_probe_device_type(ap_dev);
else
ap_dev->device_type = device_type;
ap_dev->device.bus = &ap_bus_type;
ap_dev->device.parent = ap_root_device;
if (dev_set_name(&ap_dev->device, "card%02x",
AP_QID_DEVICE(ap_dev->qid))) {
kfree(ap_dev);
continue;
}
ap_dev->device.release = ap_device_release;
rc = device_register(&ap_dev->device);
if (rc) {
put_device(&ap_dev->device);
continue;
}
/* Add device attributes. */
rc = sysfs_create_group(&ap_dev->device.kobj,
&ap_dev_attr_group);
if (!rc) {
spin_lock_bh(&ap_dev->lock);
ap_dev->unregistered = 0;
spin_unlock_bh(&ap_dev->lock);
}
else
device_unregister(&ap_dev->device);
}
}
static void
ap_config_timeout(unsigned long ptr)
{
queue_work(ap_work_queue, &ap_config_work);
ap_config_timer.expires = jiffies + ap_config_time * HZ;
add_timer(&ap_config_timer);
}
/**
* ap_schedule_poll_timer(): Schedule poll timer.
*
* Set up the timer to run the poll tasklet
*/
static inline void ap_schedule_poll_timer(void)
{
ktime_t hr_time;
spin_lock_bh(&ap_poll_timer_lock);
if (ap_using_interrupts() || ap_suspend_flag)
goto out;
if (hrtimer_is_queued(&ap_poll_timer))
goto out;
if (ktime_to_ns(hrtimer_expires_remaining(&ap_poll_timer)) <= 0) {
hr_time = ktime_set(0, poll_timeout);
hrtimer_forward_now(&ap_poll_timer, hr_time);
hrtimer_restart(&ap_poll_timer);
}
out:
spin_unlock_bh(&ap_poll_timer_lock);
}
/**
* ap_poll_read(): Receive pending reply messages from an AP device.
* @ap_dev: pointer to the AP device
* @flags: pointer to control flags, bit 2^0 is set if another poll is
* required, bit 2^1 is set if the poll timer needs to get armed
*
* Returns 0 if the device is still present, -ENODEV if not.
*/
static int ap_poll_read(struct ap_device *ap_dev, unsigned long *flags)
{
struct ap_queue_status status;
struct ap_message *ap_msg;
if (ap_dev->queue_count <= 0)
return 0;
status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid,
ap_dev->reply->message, ap_dev->reply->length);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
atomic_dec(&ap_poll_requests);
ap_decrease_queue_count(ap_dev);
list_for_each_entry(ap_msg, &ap_dev->pendingq, list) {
if (ap_msg->psmid != ap_dev->reply->psmid)
continue;
list_del_init(&ap_msg->list);
ap_dev->pendingq_count--;
ap_dev->drv->receive(ap_dev, ap_msg, ap_dev->reply);
break;
}
if (ap_dev->queue_count > 0)
*flags |= 1;
break;
case AP_RESPONSE_NO_PENDING_REPLY:
if (status.queue_empty) {
/* The card shouldn't forget requests but who knows. */
atomic_sub(ap_dev->queue_count, &ap_poll_requests);
ap_dev->queue_count = 0;
list_splice_init(&ap_dev->pendingq, &ap_dev->requestq);
ap_dev->requestq_count += ap_dev->pendingq_count;
ap_dev->pendingq_count = 0;
} else
*flags |= 2;
break;
default:
return -ENODEV;
}
return 0;
}
/**
* ap_poll_write(): Send messages from the request queue to an AP device.
* @ap_dev: pointer to the AP device
* @flags: pointer to control flags, bit 2^0 is set if another poll is
* required, bit 2^1 is set if the poll timer needs to get armed
*
* Returns 0 if the device is still present, -ENODEV if not.
*/
static int ap_poll_write(struct ap_device *ap_dev, unsigned long *flags)
{
struct ap_queue_status status;
struct ap_message *ap_msg;
if (ap_dev->requestq_count <= 0 ||
ap_dev->queue_count >= ap_dev->queue_depth)
return 0;
/* Start the next request on the queue. */
ap_msg = list_entry(ap_dev->requestq.next, struct ap_message, list);
status = __ap_send(ap_dev->qid, ap_msg->psmid,
ap_msg->message, ap_msg->length, ap_msg->special);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
atomic_inc(&ap_poll_requests);
ap_increase_queue_count(ap_dev);
list_move_tail(&ap_msg->list, &ap_dev->pendingq);
ap_dev->requestq_count--;
ap_dev->pendingq_count++;
if (ap_dev->queue_count < ap_dev->queue_depth &&
ap_dev->requestq_count > 0)
*flags |= 1;
*flags |= 2;
break;
case AP_RESPONSE_Q_FULL:
case AP_RESPONSE_RESET_IN_PROGRESS:
*flags |= 2;
break;
case AP_RESPONSE_MESSAGE_TOO_BIG:
case AP_RESPONSE_REQ_FAC_NOT_INST:
return -EINVAL;
default:
return -ENODEV;
}
return 0;
}
/**
* ap_poll_queue(): Poll AP device for pending replies and send new messages.
* @ap_dev: pointer to the bus device
* @flags: pointer to control flags, bit 2^0 is set if another poll is
* required, bit 2^1 is set if the poll timer needs to get armed
*
* Poll AP device for pending replies and send new messages. If either
* ap_poll_read or ap_poll_write returns -ENODEV unregister the device.
* Returns 0.
*/
static inline int ap_poll_queue(struct ap_device *ap_dev, unsigned long *flags)
{
int rc;
rc = ap_poll_read(ap_dev, flags);
if (rc)
return rc;
return ap_poll_write(ap_dev, flags);
}
/**
* __ap_queue_message(): Queue a message to a device.
* @ap_dev: pointer to the AP device
* @ap_msg: the message to be queued
*
* Queue a message to a device. Returns 0 if successful.
*/
static int __ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
{
struct ap_queue_status status;
if (list_empty(&ap_dev->requestq) &&
ap_dev->queue_count < ap_dev->queue_depth) {
status = __ap_send(ap_dev->qid, ap_msg->psmid,
ap_msg->message, ap_msg->length,
ap_msg->special);
switch (status.response_code) {
case AP_RESPONSE_NORMAL:
list_add_tail(&ap_msg->list, &ap_dev->pendingq);
atomic_inc(&ap_poll_requests);
ap_dev->pendingq_count++;
ap_increase_queue_count(ap_dev);
ap_dev->total_request_count++;
break;
case AP_RESPONSE_Q_FULL:
case AP_RESPONSE_RESET_IN_PROGRESS:
list_add_tail(&ap_msg->list, &ap_dev->requestq);
ap_dev->requestq_count++;
ap_dev->total_request_count++;
return -EBUSY;
case AP_RESPONSE_REQ_FAC_NOT_INST:
case AP_RESPONSE_MESSAGE_TOO_BIG:
ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-EINVAL));
return -EINVAL;
default: /* Device is gone. */
ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
return -ENODEV;
}
} else {
list_add_tail(&ap_msg->list, &ap_dev->requestq);
ap_dev->requestq_count++;
ap_dev->total_request_count++;
return -EBUSY;
}
ap_schedule_poll_timer();
return 0;
}
void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
{
unsigned long flags;
int rc;
spin_lock_bh(&ap_dev->lock);
if (!ap_dev->unregistered) {
/* Make room on the queue by polling for finished requests. */
rc = ap_poll_queue(ap_dev, &flags);
if (!rc)
rc = __ap_queue_message(ap_dev, ap_msg);
if (!rc)
wake_up(&ap_poll_wait);
if (rc == -ENODEV)
ap_dev->unregistered = 1;
} else {
ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
rc = -ENODEV;
}
spin_unlock_bh(&ap_dev->lock);
if (rc == -ENODEV)
device_unregister(&ap_dev->device);
}
EXPORT_SYMBOL(ap_queue_message);
/**
* ap_cancel_message(): Cancel a crypto request.
* @ap_dev: 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_device *ap_dev, struct ap_message *ap_msg)
{
struct ap_message *tmp;
spin_lock_bh(&ap_dev->lock);
if (!list_empty(&ap_msg->list)) {
list_for_each_entry(tmp, &ap_dev->pendingq, list)
if (tmp->psmid == ap_msg->psmid) {
ap_dev->pendingq_count--;
goto found;
}
ap_dev->requestq_count--;
found:
list_del_init(&ap_msg->list);
}
spin_unlock_bh(&ap_dev->lock);
}
EXPORT_SYMBOL(ap_cancel_message);
/**
* ap_poll_timeout(): AP receive polling for finished AP requests.
* @unused: Unused pointer.
*
* Schedules the AP tasklet using a high resolution timer.
*/
static enum hrtimer_restart ap_poll_timeout(struct hrtimer *unused)
{
tasklet_schedule(&ap_tasklet);
return HRTIMER_NORESTART;
}
/**
* ap_reset(): Reset a not responding AP device.
* @ap_dev: Pointer to the AP device
*
* Reset a not responding AP device and move all requests from the
* pending queue to the request queue.
*/
static void ap_reset(struct ap_device *ap_dev)
{
int rc;
ap_dev->reset = AP_RESET_IGNORE;
atomic_sub(ap_dev->queue_count, &ap_poll_requests);
ap_dev->queue_count = 0;
list_splice_init(&ap_dev->pendingq, &ap_dev->requestq);
ap_dev->requestq_count += ap_dev->pendingq_count;
ap_dev->pendingq_count = 0;
rc = ap_init_queue(ap_dev->qid);
if (rc == -ENODEV)
ap_dev->unregistered = 1;
}
static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags)
{
if (!ap_dev->unregistered) {
if (ap_poll_queue(ap_dev, flags))
ap_dev->unregistered = 1;
if (ap_dev->reset == AP_RESET_DO)
ap_reset(ap_dev);
}
return 0;
}
/**
* ap_poll_all(): Poll all AP devices.
* @dummy: Unused variable
*
* Poll all AP devices on the bus in a round robin fashion. Continue
* polling until bit 2^0 of the control flags is not set. If bit 2^1
* of the control flags has been set arm the poll timer.
*/
static void ap_poll_all(unsigned long dummy)
{
unsigned long flags;
struct ap_device *ap_dev;
/* Reset the indicator if interrupts are used. Thus new interrupts can
* be received. Doing it in the beginning of the tasklet is therefor
* important that no requests on any AP get lost.
*/
if (ap_using_interrupts())
xchg((u8 *)ap_interrupt_indicator, 0);
do {
flags = 0;
spin_lock(&ap_device_list_lock);
list_for_each_entry(ap_dev, &ap_device_list, list) {
spin_lock(&ap_dev->lock);
__ap_poll_device(ap_dev, &flags);
spin_unlock(&ap_dev->lock);
}
spin_unlock(&ap_device_list_lock);
} while (flags & 1);
if (flags & 2)
ap_schedule_poll_timer();
}
/**
* ap_poll_thread(): Thread that polls for finished requests.
* @data: Unused pointer
*
* AP bus poll thread. The purpose of this thread is to poll for
* finished requests in a loop if there is a "free" cpu - that is
* a cpu that doesn't have anything better to do. The polling stops
* as soon as there is another task or if all messages have been
* delivered.
*/
static int ap_poll_thread(void *data)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long flags;
int requests;
struct ap_device *ap_dev;
set_user_nice(current, 19);
while (1) {
if (ap_suspend_flag)
return 0;
if (need_resched()) {
schedule();
continue;
}
add_wait_queue(&ap_poll_wait, &wait);
set_current_state(TASK_INTERRUPTIBLE);
if (kthread_should_stop())
break;
requests = atomic_read(&ap_poll_requests);
if (requests <= 0)
schedule();
set_current_state(TASK_RUNNING);
remove_wait_queue(&ap_poll_wait, &wait);
flags = 0;
spin_lock_bh(&ap_device_list_lock);
list_for_each_entry(ap_dev, &ap_device_list, list) {
spin_lock(&ap_dev->lock);
__ap_poll_device(ap_dev, &flags);
spin_unlock(&ap_dev->lock);
}
spin_unlock_bh(&ap_device_list_lock);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&ap_poll_wait, &wait);
return 0;
}
static int ap_poll_thread_start(void)
{
int rc;
if (ap_using_interrupts() || ap_suspend_flag)
return 0;
mutex_lock(&ap_poll_thread_mutex);
if (!ap_poll_kthread) {
ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
rc = IS_ERR(ap_poll_kthread) ? PTR_ERR(ap_poll_kthread) : 0;
if (rc)
ap_poll_kthread = NULL;
}
else
rc = 0;
mutex_unlock(&ap_poll_thread_mutex);
return rc;
}
static void ap_poll_thread_stop(void)
{
mutex_lock(&ap_poll_thread_mutex);
if (ap_poll_kthread) {
kthread_stop(ap_poll_kthread);
ap_poll_kthread = NULL;
}
mutex_unlock(&ap_poll_thread_mutex);
}
/**
* ap_request_timeout(): Handling of request timeouts
* @data: Holds the AP device.
*
* Handles request timeouts.
*/
static void ap_request_timeout(unsigned long data)
{
struct ap_device *ap_dev = (struct ap_device *) data;
if (ap_dev->reset == AP_RESET_ARMED) {
ap_dev->reset = AP_RESET_DO;
if (ap_using_interrupts())
tasklet_schedule(&ap_tasklet);
}
}
static void ap_reset_domain(void)
{
int i;
if (ap_domain_index != -1)
for (i = 0; i < AP_DEVICES; i++)
ap_reset_queue(AP_MKQID(i, ap_domain_index));
}
static void ap_reset_all(void)
{
int i, j;
for (i = 0; i < AP_DOMAINS; i++)
for (j = 0; j < AP_DEVICES; j++)
ap_reset_queue(AP_MKQID(j, i));
}
static struct reset_call ap_reset_call = {
.fn = ap_reset_all,
};
/**
* ap_module_init(): The module initialization code.
*
* Initializes the module.
*/
int __init ap_module_init(void)
{
int rc, i;
if (ap_domain_index < -1 || ap_domain_index >= AP_DOMAINS) {
pr_warning("%d is not a valid cryptographic domain\n",
ap_domain_index);
return -EINVAL;
}
/* In resume callback we need to know if the user had set the domain.
* If so, we can not just reset it.
*/
if (ap_domain_index >= 0)
user_set_domain = 1;
if (ap_instructions_available() != 0) {
pr_warning("The hardware system does not support "
"AP instructions\n");
return -ENODEV;
}
if (ap_interrupts_available()) {
isc_register(AP_ISC);
ap_interrupt_indicator = s390_register_adapter_interrupt(
&ap_interrupt_handler, NULL, AP_ISC);
if (IS_ERR(ap_interrupt_indicator)) {
ap_interrupt_indicator = NULL;
isc_unregister(AP_ISC);
}
}
register_reset_call(&ap_reset_call);
/* Create /sys/bus/ap. */
rc = bus_register(&ap_bus_type);
if (rc)
goto out;
for (i = 0; ap_bus_attrs[i]; i++) {
rc = bus_create_file(&ap_bus_type, ap_bus_attrs[i]);
if (rc)
goto out_bus;
}
/* Create /sys/devices/ap. */
ap_root_device = root_device_register("ap");
rc = IS_ERR(ap_root_device) ? PTR_ERR(ap_root_device) : 0;
if (rc)
goto out_bus;
ap_work_queue = create_singlethread_workqueue("kapwork");
if (!ap_work_queue) {
rc = -ENOMEM;
goto out_root;
}
if (ap_select_domain() == 0)
ap_scan_bus(NULL);
/* Setup the AP bus rescan timer. */
init_timer(&ap_config_timer);
ap_config_timer.function = ap_config_timeout;
ap_config_timer.data = 0;
ap_config_timer.expires = jiffies + ap_config_time * HZ;
add_timer(&ap_config_timer);
/* Setup the high resultion poll timer.
* If we are running under z/VM adjust polling to z/VM polling rate.
*/
if (MACHINE_IS_VM)
poll_timeout = 1500000;
spin_lock_init(&ap_poll_timer_lock);
hrtimer_init(&ap_poll_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
ap_poll_timer.function = ap_poll_timeout;
/* Start the low priority AP bus poll thread. */
if (ap_thread_flag) {
rc = ap_poll_thread_start();
if (rc)
goto out_work;
}
return 0;
out_work:
del_timer_sync(&ap_config_timer);
hrtimer_cancel(&ap_poll_timer);
destroy_workqueue(ap_work_queue);
out_root:
root_device_unregister(ap_root_device);
out_bus:
while (i--)
bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
bus_unregister(&ap_bus_type);
out:
unregister_reset_call(&ap_reset_call);
if (ap_using_interrupts()) {
s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
isc_unregister(AP_ISC);
}
return rc;
}
static int __ap_match_all(struct device *dev, void *data)
{
return 1;
}
/**
* ap_modules_exit(): The module termination code
*
* Terminates the module.
*/
void ap_module_exit(void)
{
int i;
struct device *dev;
ap_reset_domain();
ap_poll_thread_stop();
del_timer_sync(&ap_config_timer);
hrtimer_cancel(&ap_poll_timer);
destroy_workqueue(ap_work_queue);
tasklet_kill(&ap_tasklet);
root_device_unregister(ap_root_device);
while ((dev = bus_find_device(&ap_bus_type, NULL, NULL,
__ap_match_all)))
{
device_unregister(dev);
put_device(dev);
}
for (i = 0; ap_bus_attrs[i]; i++)
bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
bus_unregister(&ap_bus_type);
unregister_reset_call(&ap_reset_call);
if (ap_using_interrupts()) {
s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
isc_unregister(AP_ISC);
}
}
#ifndef CONFIG_ZCRYPT_MONOLITHIC
module_init(ap_module_init);
module_exit(ap_module_exit);
#endif