[S390] zcrypt: Use of Thin Interrupts (cb17a636) · Commits · e / devices / android_kernel_fairphone_FP3

arch/s390/include/asm/isc.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		#define CHSC_SCH_ISC 7 /* CHSC subchannels */
		/* Adapter interrupts. */
		#define QDIO_AIRQ_ISC IO_SCH_ISC /* I/O subchannel in qdio mode */
		#define AP_ISC 6 /* adjunct processor (crypto) devices */

		/* Functions for registration of I/O interruption subclasses */
		void isc_register(unsigned int isc);

drivers/s390/crypto/ap_bus.c

+171 −3

Original line number	Diff line number	Diff line
		@@ -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.
		*
		@@ -34,6 +35,10 @@
		#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 +51,7 @@ 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.
		@@ -80,18 +86,28 @@ 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.
		*
		@@ -112,6 +128,23 @@ static inline int ap_instructions_available(void)
		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
		@@ -152,6 +185,80 @@ 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 +402,11 @@ 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 +457,15 @@ 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;
		}

		@@ -599,6 +720,14 @@ 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 +782,8 @@ 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 +802,7 @@ 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 +945,11 @@ static int ap_probe_device_type(struct ap_device *ap_dev)
		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 +1064,8 @@ 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),
		@@ -1207,6 +1345,12 @@ 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);
		@@ -1268,6 +1412,8 @@ 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 +1447,12 @@ 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)
		@@ -1345,6 +1495,16 @@ int __init ap_module_init(void)
		printk(KERN_WARNING "AP instructions not installed.\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 +1568,10 @@ int __init ap_module_init(void)
		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 +1607,10 @@ 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

drivers/s390/crypto/ap_bus.h

+5 −1

Original line number	Diff line number	Diff line
		@@ -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 header file.
		*
		@@ -67,7 +68,8 @@ struct ap_queue_status {
		unsigned int queue_empty : 1;
		unsigned int replies_waiting : 1;
		unsigned int queue_full : 1;
		unsigned int pad1 : 5;
		unsigned int pad1 : 4;
		unsigned int int_enabled : 1;
		unsigned int response_code : 8;
		unsigned int pad2 : 16;
		};
		@@ -78,6 +80,8 @@ struct ap_queue_status {
		#define AP_RESPONSE_DECONFIGURED 0x03
		#define AP_RESPONSE_CHECKSTOPPED 0x04
		#define AP_RESPONSE_BUSY 0x05
		#define AP_RESPONSE_INVALID_ADDRESS 0x06
		#define AP_RESPONSE_OTHERWISE_CHANGED 0x07
		#define AP_RESPONSE_Q_FULL 0x10
		#define AP_RESPONSE_NO_PENDING_REPLY 0x10
		#define AP_RESPONSE_INDEX_TOO_BIG 0x11