[S390] cleanup lowcore access from external interrupts

Read external interrupts parameters from the lowcore in the first
level interrupt handler in entry[64].S.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/s390_ext.h

@@ -12,7 +12,7 @@
 
 #include <linux/types.h>
 
-typedef void (*ext_int_handler_t)(__u16 code);
+typedef void (*ext_int_handler_t)(unsigned int, unsigned int, unsigned long);
 
 typedef struct ext_int_info_t {
 	struct ext_int_info_t *next;

arch/s390/kernel/asm-offsets.c

@@ -143,10 +143,8 @@ int main(void)
 	DEFINE(__LC_GPREGS_SAVE_AREA, offsetof(struct _lowcore, gpregs_save_area));
 	DEFINE(__LC_CREGS_SAVE_AREA, offsetof(struct _lowcore, cregs_save_area));
 #ifdef CONFIG_32BIT
-	DEFINE(__LC_PFAULT_INTPARM, offsetof(struct _lowcore, ext_params));
 	DEFINE(SAVE_AREA_BASE, offsetof(struct _lowcore, extended_save_area_addr));
 #else /* CONFIG_32BIT */
-	DEFINE(__LC_PFAULT_INTPARM, offsetof(struct _lowcore, ext_params2));
 	DEFINE(__LC_EXT_PARAMS2, offsetof(struct _lowcore, ext_params2));
 	DEFINE(SAVE_AREA_BASE, offsetof(struct _lowcore, floating_pt_save_area));
 	DEFINE(__LC_PASTE, offsetof(struct _lowcore, paste));

arch/s390/kernel/entry.S

@@ -722,7 +722,8 @@ ext_no_vtime:
 	l	%r9,__LC_THREAD_INFO	# load pointer to thread_info struct
 	TRACE_IRQS_OFF
 	la	%r2,SP_PTREGS(%r15)	# address of register-save area
-	lh	%r3,__LC_EXT_INT_CODE	# get interruption code
+	l	%r3,__LC_CPU_ADDRESS	# get cpu address + interruption code
+	l	%r4,__LC_EXT_PARAMS	# get external parameters
 	l	%r1,BASED(.Ldo_extint)
 	basr	%r14,%r1
 	b	BASED(io_return)

arch/s390/kernel/entry.h

@@ -19,7 +19,7 @@ void do_signal(struct pt_regs *regs);
 int handle_signal32(unsigned long sig, struct k_sigaction *ka,
 		    siginfo_t *info, sigset_t *oldset, struct pt_regs *regs);
 
-void do_extint(struct pt_regs *regs, unsigned short code);
+void do_extint(struct pt_regs *regs, unsigned int, unsigned int, unsigned long);
 int __cpuinit start_secondary(void *cpuvoid);
 void __init startup_init(void);
 void die(const char * str, struct pt_regs * regs, long err);

arch/s390/kernel/entry64.S

@@ -727,8 +727,11 @@ ext_int_handler:
 ext_no_vtime:
 	HANDLE_SIE_INTERCEPT
 	TRACE_IRQS_OFF
+	lghi	%r1,4096
 	la	%r2,SP_PTREGS(%r15)	# address of register-save area
-	llgh	%r3,__LC_EXT_INT_CODE	# get interruption code
+	llgf	%r3,__LC_CPU_ADDRESS	# get cpu address + interruption code
+	llgf	%r4,__LC_EXT_PARAMS	# get external parameter
+	lg	%r5,__LC_EXT_PARAMS2-4096(%r1)	# get 64 bit external parameter
 	brasl	%r14,do_extint
 	j	io_return
 

arch/s390/kernel/s390_ext.c

@@ -113,12 +113,15 @@ int unregister_early_external_interrupt(__u16 code, ext_int_handler_t handler,
 	return 0;
 }
 
-void __irq_entry do_extint(struct pt_regs *regs, unsigned short code)
+void __irq_entry do_extint(struct pt_regs *regs, unsigned int ext_int_code,
+			   unsigned int param32, unsigned long param64)
 {
+	struct pt_regs *old_regs;
+	unsigned short code;
         ext_int_info_t *p;
         int index;
-	struct pt_regs *old_regs;
 
+	code = (unsigned short) ext_int_code;
 	old_regs = set_irq_regs(regs);
 	s390_idle_check(regs, S390_lowcore.int_clock,
 			S390_lowcore.async_enter_timer);
@@ -132,7 +135,7 @@ void __irq_entry do_extint(struct pt_regs *regs, unsigned short code)
         index = ext_hash(code);
 	for (p = ext_int_hash[index]; p; p = p->next) {
 		if (likely(p->code == code))
-			p->handler(code);
+			p->handler(ext_int_code, param32, param64);
 	}
 	irq_exit();
 	set_irq_regs(old_regs);

arch/s390/kernel/smp.c

@@ -156,7 +156,8 @@ void smp_send_stop(void)
  * cpus are handled.
  */
 
-static void do_ext_call_interrupt(__u16 code)
+static void do_ext_call_interrupt(unsigned int ext_int_code,
+				  unsigned int param32, unsigned long param64)
 {
 	unsigned long bits;
 

arch/s390/kernel/time.c

@@ -155,7 +155,9 @@ void init_cpu_timer(void)
 	__ctl_set_bit(0, 4);
 }
 
-static void clock_comparator_interrupt(__u16 code)
+static void clock_comparator_interrupt(unsigned int ext_int_code,
+				       unsigned int param32,
+				       unsigned long param64)
 {
 	if (S390_lowcore.clock_comparator == -1ULL)
 		set_clock_comparator(S390_lowcore.clock_comparator);
@@ -164,14 +166,13 @@ static void clock_comparator_interrupt(__u16 code)
 static void etr_timing_alert(struct etr_irq_parm *);
 static void stp_timing_alert(struct stp_irq_parm *);
 
-static void timing_alert_interrupt(__u16 code)
+static void timing_alert_interrupt(unsigned int ext_int_code,
+				   unsigned int param32, unsigned long param64)
 {
-	if (S390_lowcore.ext_params & 0x00c40000)
-		etr_timing_alert((struct etr_irq_parm *)
-				 &S390_lowcore.ext_params);
-	if (S390_lowcore.ext_params & 0x00038000)
-		stp_timing_alert((struct stp_irq_parm *)
-				 &S390_lowcore.ext_params);
+	if (param32 & 0x00c40000)
+		etr_timing_alert((struct etr_irq_parm *) &param32);
+	if (param32 & 0x00038000)
+		stp_timing_alert((struct stp_irq_parm *) &param32);
 }
 
 static void etr_reset(void);

arch/s390/kernel/vtime.c

@@ -314,7 +314,8 @@ static void do_callbacks(struct list_head *cb_list)
 /*
  * Handler for the virtual CPU timer.
  */
-static void do_cpu_timer_interrupt(__u16 error_code)
+static void do_cpu_timer_interrupt(unsigned int ext_int_code,
+				   unsigned int param32, unsigned long param64)
 {
 	struct vtimer_queue *vq;
 	struct vtimer_list *event, *tmp;

arch/s390/mm/fault.c

@@ -542,7 +542,8 @@ void pfault_fini(void)
 		: : "a" (&refbk), "m" (refbk) : "cc");
 }
 
-static void pfault_interrupt(__u16 int_code)
+static void pfault_interrupt(unsigned int ext_int_code,
+			     unsigned int param32, unsigned long param64)
 {
 	struct task_struct *tsk;
 	__u16 subcode;
@@ -553,14 +554,18 @@ static void pfault_interrupt(__u16 int_code)
 	 * in the 'cpu address' field associated with the
          * external interrupt. 
 	 */
-	subcode = S390_lowcore.cpu_addr;
+	subcode = ext_int_code >> 16;
 	if ((subcode & 0xff00) != __SUBCODE_MASK)
 		return;
 
 	/*
 	 * Get the token (= address of the task structure of the affected task).
 	 */
-	tsk = *(struct task_struct **) __LC_PFAULT_INTPARM;
+#ifdef CONFIG_64BIT
+	tsk = *(struct task_struct **) param64;
+#else
+	tsk = *(struct task_struct **) param32;
+#endif
 
 	if (subcode & 0x0080) {
 		/* signal bit is set -> a page has been swapped in by VM */

drivers/s390/block/dasd_diag.c

@@ -228,25 +228,22 @@ dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 }
 
 /* Handle external interruption. */
-static void
-dasd_ext_handler(__u16 code)
+static void dasd_ext_handler(unsigned int ext_int_code,
+			     unsigned int param32, unsigned long param64)
 {
 	struct dasd_ccw_req *cqr, *next;
 	struct dasd_device *device;
 	unsigned long long expires;
 	unsigned long flags;
-	u8 int_code, status;
 	addr_t ip;
 	int rc;
 
-	int_code = *((u8 *) DASD_DIAG_LC_INT_CODE);
-	status = *((u8 *) DASD_DIAG_LC_INT_STATUS);
-	switch (int_code) {
+	switch (ext_int_code >> 24) {
 	case DASD_DIAG_CODE_31BIT:
-		ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT);
+		ip = (addr_t) param32;
 		break;
 	case DASD_DIAG_CODE_64BIT:
-		ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT);
+		ip = (addr_t) param64;
 		break;
 	default:
 		return;
@@ -281,7 +278,7 @@ dasd_ext_handler(__u16 code)
 	cqr->stopclk = get_clock();
 
 	expires = 0;
-	if (status == 0) {
+	if ((ext_int_code & 0xff0000) == 0) {
 		cqr->status = DASD_CQR_SUCCESS;
 		/* Start first request on queue if possible -> fast_io. */
 		if (!list_empty(&device->ccw_queue)) {
@@ -296,8 +293,8 @@ dasd_ext_handler(__u16 code)
 	} else {
 		cqr->status = DASD_CQR_QUEUED;
 		DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
-			    "request %p was %d (%d retries left)", cqr, status,
-			    cqr->retries);
+			      "request %p was %d (%d retries left)", cqr,
+			      (ext_int_code >> 16) & 0xff, cqr->retries);
 		dasd_diag_erp(device);
 	}
 

drivers/s390/block/dasd_diag.h

@@ -18,10 +18,6 @@
 #define DEV_CLASS_FBA	0x01
 #define DEV_CLASS_ECKD	0x04
 
-#define DASD_DIAG_LC_INT_CODE		132
-#define DASD_DIAG_LC_INT_STATUS		133
-#define DASD_DIAG_LC_INT_PARM_31BIT	128
-#define DASD_DIAG_LC_INT_PARM_64BIT	4536
 #define DASD_DIAG_CODE_31BIT		0x03
 #define DASD_DIAG_CODE_64BIT		0x07
 

drivers/s390/char/sclp.c

@@ -395,16 +395,16 @@ __sclp_find_req(u32 sccb)
 /* Handler for external interruption. Perform request post-processing.
  * Prepare read event data request if necessary. Start processing of next
  * request on queue. */
-static void
-sclp_interrupt_handler(__u16 code)
+static void sclp_interrupt_handler(unsigned int ext_int_code,
+				   unsigned int param32, unsigned long param64)
 {
 	struct sclp_req *req;
 	u32 finished_sccb;
 	u32 evbuf_pending;
 
 	spin_lock(&sclp_lock);
-	finished_sccb = S390_lowcore.ext_params & 0xfffffff8;
-	evbuf_pending = S390_lowcore.ext_params & 0x3;
+	finished_sccb = param32 & 0xfffffff8;
+	evbuf_pending = param32 & 0x3;
 	if (finished_sccb) {
 		del_timer(&sclp_request_timer);
 		sclp_running_state = sclp_running_state_reset_pending;
@@ -819,12 +819,12 @@ EXPORT_SYMBOL(sclp_reactivate);
 
 /* Handler for external interruption used during initialization. Modify
  * request state to done. */
-static void
-sclp_check_handler(__u16 code)
+static void sclp_check_handler(unsigned int ext_int_code,
+			       unsigned int param32, unsigned long param64)
 {
 	u32 finished_sccb;
 
-	finished_sccb = S390_lowcore.ext_params & 0xfffffff8;
+	finished_sccb = param32 & 0xfffffff8;
 	/* Is this the interrupt we are waiting for? */
 	if (finished_sccb == 0)
 		return;

drivers/s390/kvm/kvm_virtio.c

@@ -372,21 +372,22 @@ static void hotplug_devices(struct work_struct *dummy)
 /*
  * we emulate the request_irq behaviour on top of s390 extints
  */
-static void kvm_extint_handler(u16 code)
+static void kvm_extint_handler(unsigned int ext_int_code,
+			       unsigned int param32, unsigned long param64)
 {
 	struct virtqueue *vq;
 	u16 subcode;
 	u32 param;
 
-	subcode = S390_lowcore.cpu_addr;
+	subcode = ext_int_code >> 16;
 	if ((subcode & 0xff00) != VIRTIO_SUBCODE_64)
 		return;
 
 	/* The LSB might be overloaded, we have to mask it */
-	vq = (struct virtqueue *)(S390_lowcore.ext_params2 & ~1UL);
+	vq = (struct virtqueue *)(param64 & ~1UL);
 
 	/* We use ext_params to decide what this interrupt means */
-	param = S390_lowcore.ext_params & VIRTIO_PARAM_MASK;
+	param = param32 & VIRTIO_PARAM_MASK;
 
 	switch (param) {
 	case VIRTIO_PARAM_CONFIG_CHANGED:

net/iucv/iucv.c

@@ -1798,7 +1798,8 @@ static void iucv_work_fn(struct work_struct *work)
  * Handles external interrupts coming in from CP.
  * Places the interrupt buffer on a queue and schedules iucv_tasklet_fn().
  */
-static void iucv_external_interrupt(u16 code)
+static void iucv_external_interrupt(unsigned int ext_int_code,
+				    unsigned int param32, unsigned long param64)
 {
 	struct iucv_irq_data *p;
 	struct iucv_irq_list *work;