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path: root/drivers/s390/crypto/ap_bus.c
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Diffstat (limited to 'drivers/s390/crypto/ap_bus.c')
-rw-r--r--drivers/s390/crypto/ap_bus.c212
1 files changed, 192 insertions, 20 deletions
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index e3fe6838293a..1f5f5d2d87d9 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -5,6 +5,7 @@
* 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.
*
@@ -23,6 +24,9 @@
* 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>
@@ -34,6 +38,10 @@
#include <linux/mutex.h>
#include <asm/s390_rdev.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>
@@ -46,6 +54,7 @@ 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);
/*
* Module description.
@@ -68,7 +77,7 @@ 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_lock);
+static DEFINE_SPINLOCK(ap_device_list_lock);
static LIST_HEAD(ap_device_list);
/*
@@ -80,19 +89,29 @@ static int ap_config_time = AP_CONFIG_TIME;
static DECLARE_WORK(ap_config_work, ap_scan_bus);
/*
- * Tasklet & timer for AP request polling.
+ * 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 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;
/**
+ * 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.
@@ -113,6 +132,23 @@ static inline int ap_instructions_available(void)
}
/**
+ * 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
@@ -152,6 +188,80 @@ static inline struct ap_queue_status ap_reset_queue(ap_qid_t qid)
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
@@ -295,6 +405,11 @@ static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type)
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:
@@ -345,6 +460,15 @@ static int ap_init_queue(ap_qid_t qid)
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;
}
@@ -397,16 +521,16 @@ static ssize_t ap_hwtype_show(struct device *dev,
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 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 DEVICE_ATTR(depth, 0444, ap_depth_show, NULL);
static ssize_t ap_request_count_show(struct device *dev,
struct device_attribute *attr,
char *buf)
@@ -509,9 +633,9 @@ static int ap_device_probe(struct device *dev)
ap_dev->drv = ap_drv;
rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV;
if (!rc) {
- spin_lock_bh(&ap_device_lock);
+ spin_lock_bh(&ap_device_list_lock);
list_add(&ap_dev->list, &ap_device_list);
- spin_unlock_bh(&ap_device_lock);
+ spin_unlock_bh(&ap_device_list_lock);
}
return rc;
}
@@ -553,9 +677,9 @@ static int ap_device_remove(struct device *dev)
ap_flush_queue(ap_dev);
del_timer_sync(&ap_dev->timeout);
- spin_lock_bh(&ap_device_lock);
+ spin_lock_bh(&ap_device_list_lock);
list_del_init(&ap_dev->list);
- spin_unlock_bh(&ap_device_lock);
+ spin_unlock_bh(&ap_device_list_lock);
if (ap_drv->remove)
ap_drv->remove(ap_dev);
spin_lock_bh(&ap_dev->lock);
@@ -599,6 +723,14 @@ 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)
{
@@ -653,7 +785,8 @@ static ssize_t poll_timeout_store(struct bus_type *bus, const char *buf,
ktime_t hr_time;
/* 120 seconds = maximum poll interval */
- if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 || time > 120000000000)
+ if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 ||
+ time > 120000000000ULL)
return -EINVAL;
poll_timeout = time;
hr_time = ktime_set(0, poll_timeout);
@@ -672,6 +805,7 @@ 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,
};
@@ -814,6 +948,11 @@ 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
@@ -928,6 +1067,8 @@ ap_config_timeout(unsigned long ptr)
*/
static inline void ap_schedule_poll_timer(void)
{
+ if (ap_using_interrupts())
+ return;
if (hrtimer_is_queued(&ap_poll_timer))
return;
hrtimer_start(&ap_poll_timer, ktime_set(0, poll_timeout),
@@ -1181,7 +1322,7 @@ static void ap_reset(struct ap_device *ap_dev)
ap_dev->unregistered = 1;
}
-static int __ap_poll_all(struct ap_device *ap_dev, unsigned long *flags)
+static int __ap_poll_device(struct ap_device *ap_dev, unsigned long *flags)
{
spin_lock(&ap_dev->lock);
if (!ap_dev->unregistered) {
@@ -1207,13 +1348,19 @@ 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_lock);
+ spin_lock(&ap_device_list_lock);
list_for_each_entry(ap_dev, &ap_device_list, list) {
- __ap_poll_all(ap_dev, &flags);
+ __ap_poll_device(ap_dev, &flags);
}
- spin_unlock(&ap_device_lock);
+ spin_unlock(&ap_device_list_lock);
} while (flags & 1);
if (flags & 2)
ap_schedule_poll_timer();
@@ -1253,11 +1400,11 @@ static int ap_poll_thread(void *data)
remove_wait_queue(&ap_poll_wait, &wait);
flags = 0;
- spin_lock_bh(&ap_device_lock);
+ spin_lock_bh(&ap_device_list_lock);
list_for_each_entry(ap_dev, &ap_device_list, list) {
- __ap_poll_all(ap_dev, &flags);
+ __ap_poll_device(ap_dev, &flags);
}
- spin_unlock_bh(&ap_device_lock);
+ spin_unlock_bh(&ap_device_list_lock);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&ap_poll_wait, &wait);
@@ -1268,6 +1415,8 @@ static int ap_poll_thread_start(void)
{
int rc;
+ if (ap_using_interrupts())
+ return 0;
mutex_lock(&ap_poll_thread_mutex);
if (!ap_poll_kthread) {
ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
@@ -1301,8 +1450,12 @@ static void ap_request_timeout(unsigned long data)
{
struct ap_device *ap_dev = (struct ap_device *) data;
- if (ap_dev->reset == AP_RESET_ARMED)
+ 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)
@@ -1337,14 +1490,25 @@ int __init ap_module_init(void)
int rc, i;
if (ap_domain_index < -1 || ap_domain_index >= AP_DOMAINS) {
- printk(KERN_WARNING "Invalid param: domain = %d. "
- " Not loading.\n", ap_domain_index);
+ pr_warning("%d is not a valid cryptographic domain\n",
+ ap_domain_index);
return -EINVAL;
}
if (ap_instructions_available() != 0) {
- printk(KERN_WARNING "AP instructions not installed.\n");
+ 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. */
@@ -1408,6 +1572,10 @@ out_bus:
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;
}
@@ -1443,6 +1611,10 @@ void ap_module_exit(void)
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
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.