Btrfs: don't wait as long for more batches during SSD log commit
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / s390 / kvm / interrupt.c
blobc9aeb4b4d0b84e67c9cc5ae1bf6648d31ea7c6dd
1 /*
2 * interrupt.c - handling kvm guest interrupts
4 * Copyright IBM Corp. 2008
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License (version 2 only)
8 * as published by the Free Software Foundation.
10 * Author(s): Carsten Otte <cotte@de.ibm.com>
13 #include <linux/interrupt.h>
14 #include <linux/kvm_host.h>
15 #include <linux/hrtimer.h>
16 #include <linux/signal.h>
17 #include <linux/slab.h>
18 #include <asm/asm-offsets.h>
19 #include <asm/uaccess.h>
20 #include "kvm-s390.h"
21 #include "gaccess.h"
23 static int psw_extint_disabled(struct kvm_vcpu *vcpu)
25 return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
28 static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
30 if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
31 (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) ||
32 (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT))
33 return 0;
34 return 1;
37 static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
38 struct kvm_s390_interrupt_info *inti)
40 switch (inti->type) {
41 case KVM_S390_INT_EMERGENCY:
42 if (psw_extint_disabled(vcpu))
43 return 0;
44 if (vcpu->arch.sie_block->gcr[0] & 0x4000ul)
45 return 1;
46 return 0;
47 case KVM_S390_INT_SERVICE:
48 if (psw_extint_disabled(vcpu))
49 return 0;
50 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
51 return 1;
52 return 0;
53 case KVM_S390_INT_VIRTIO:
54 if (psw_extint_disabled(vcpu))
55 return 0;
56 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
57 return 1;
58 return 0;
59 case KVM_S390_PROGRAM_INT:
60 case KVM_S390_SIGP_STOP:
61 case KVM_S390_SIGP_SET_PREFIX:
62 case KVM_S390_RESTART:
63 return 1;
64 default:
65 BUG();
67 return 0;
70 static void __set_cpu_idle(struct kvm_vcpu *vcpu)
72 BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
73 atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
74 set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
77 static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
79 BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
80 atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
81 clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
84 static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
86 atomic_clear_mask(CPUSTAT_ECALL_PEND |
87 CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
88 &vcpu->arch.sie_block->cpuflags);
89 vcpu->arch.sie_block->lctl = 0x0000;
92 static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
94 atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags);
97 static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
98 struct kvm_s390_interrupt_info *inti)
100 switch (inti->type) {
101 case KVM_S390_INT_EMERGENCY:
102 case KVM_S390_INT_SERVICE:
103 case KVM_S390_INT_VIRTIO:
104 if (psw_extint_disabled(vcpu))
105 __set_cpuflag(vcpu, CPUSTAT_EXT_INT);
106 else
107 vcpu->arch.sie_block->lctl |= LCTL_CR0;
108 break;
109 case KVM_S390_SIGP_STOP:
110 __set_cpuflag(vcpu, CPUSTAT_STOP_INT);
111 break;
112 default:
113 BUG();
117 static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
118 struct kvm_s390_interrupt_info *inti)
120 const unsigned short table[] = { 2, 4, 4, 6 };
121 int rc, exception = 0;
123 switch (inti->type) {
124 case KVM_S390_INT_EMERGENCY:
125 VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg");
126 vcpu->stat.deliver_emergency_signal++;
127 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1201);
128 if (rc == -EFAULT)
129 exception = 1;
131 rc = put_guest_u16(vcpu, __LC_CPU_ADDRESS, inti->emerg.code);
132 if (rc == -EFAULT)
133 exception = 1;
135 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
136 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
137 if (rc == -EFAULT)
138 exception = 1;
140 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
141 __LC_EXT_NEW_PSW, sizeof(psw_t));
142 if (rc == -EFAULT)
143 exception = 1;
144 break;
146 case KVM_S390_INT_SERVICE:
147 VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x",
148 inti->ext.ext_params);
149 vcpu->stat.deliver_service_signal++;
150 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2401);
151 if (rc == -EFAULT)
152 exception = 1;
154 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
155 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
156 if (rc == -EFAULT)
157 exception = 1;
159 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
160 __LC_EXT_NEW_PSW, sizeof(psw_t));
161 if (rc == -EFAULT)
162 exception = 1;
164 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
165 if (rc == -EFAULT)
166 exception = 1;
167 break;
169 case KVM_S390_INT_VIRTIO:
170 VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%llx",
171 inti->ext.ext_params, inti->ext.ext_params2);
172 vcpu->stat.deliver_virtio_interrupt++;
173 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2603);
174 if (rc == -EFAULT)
175 exception = 1;
177 rc = put_guest_u16(vcpu, __LC_CPU_ADDRESS, 0x0d00);
178 if (rc == -EFAULT)
179 exception = 1;
181 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
182 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
183 if (rc == -EFAULT)
184 exception = 1;
186 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
187 __LC_EXT_NEW_PSW, sizeof(psw_t));
188 if (rc == -EFAULT)
189 exception = 1;
191 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
192 if (rc == -EFAULT)
193 exception = 1;
195 rc = put_guest_u64(vcpu, __LC_EXT_PARAMS2,
196 inti->ext.ext_params2);
197 if (rc == -EFAULT)
198 exception = 1;
199 break;
201 case KVM_S390_SIGP_STOP:
202 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop");
203 vcpu->stat.deliver_stop_signal++;
204 __set_intercept_indicator(vcpu, inti);
205 break;
207 case KVM_S390_SIGP_SET_PREFIX:
208 VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x",
209 inti->prefix.address);
210 vcpu->stat.deliver_prefix_signal++;
211 vcpu->arch.sie_block->prefix = inti->prefix.address;
212 vcpu->arch.sie_block->ihcpu = 0xffff;
213 break;
215 case KVM_S390_RESTART:
216 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart");
217 vcpu->stat.deliver_restart_signal++;
218 rc = copy_to_guest(vcpu, offsetof(struct _lowcore,
219 restart_old_psw), &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
220 if (rc == -EFAULT)
221 exception = 1;
223 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
224 offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
225 if (rc == -EFAULT)
226 exception = 1;
227 break;
229 case KVM_S390_PROGRAM_INT:
230 VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x",
231 inti->pgm.code,
232 table[vcpu->arch.sie_block->ipa >> 14]);
233 vcpu->stat.deliver_program_int++;
234 rc = put_guest_u16(vcpu, __LC_PGM_INT_CODE, inti->pgm.code);
235 if (rc == -EFAULT)
236 exception = 1;
238 rc = put_guest_u16(vcpu, __LC_PGM_ILC,
239 table[vcpu->arch.sie_block->ipa >> 14]);
240 if (rc == -EFAULT)
241 exception = 1;
243 rc = copy_to_guest(vcpu, __LC_PGM_OLD_PSW,
244 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
245 if (rc == -EFAULT)
246 exception = 1;
248 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
249 __LC_PGM_NEW_PSW, sizeof(psw_t));
250 if (rc == -EFAULT)
251 exception = 1;
252 break;
254 default:
255 BUG();
257 if (exception) {
258 printk("kvm: The guest lowcore is not mapped during interrupt "
259 "delivery, killing userspace\n");
260 do_exit(SIGKILL);
264 static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
266 int rc, exception = 0;
268 if (psw_extint_disabled(vcpu))
269 return 0;
270 if (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))
271 return 0;
272 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1004);
273 if (rc == -EFAULT)
274 exception = 1;
275 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
276 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
277 if (rc == -EFAULT)
278 exception = 1;
279 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
280 __LC_EXT_NEW_PSW, sizeof(psw_t));
281 if (rc == -EFAULT)
282 exception = 1;
283 if (exception) {
284 printk("kvm: The guest lowcore is not mapped during interrupt "
285 "delivery, killing userspace\n");
286 do_exit(SIGKILL);
288 return 1;
291 static int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
293 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
294 struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
295 struct kvm_s390_interrupt_info *inti;
296 int rc = 0;
298 if (atomic_read(&li->active)) {
299 spin_lock_bh(&li->lock);
300 list_for_each_entry(inti, &li->list, list)
301 if (__interrupt_is_deliverable(vcpu, inti)) {
302 rc = 1;
303 break;
305 spin_unlock_bh(&li->lock);
308 if ((!rc) && atomic_read(&fi->active)) {
309 spin_lock(&fi->lock);
310 list_for_each_entry(inti, &fi->list, list)
311 if (__interrupt_is_deliverable(vcpu, inti)) {
312 rc = 1;
313 break;
315 spin_unlock(&fi->lock);
318 if ((!rc) && (vcpu->arch.sie_block->ckc <
319 get_clock() + vcpu->arch.sie_block->epoch)) {
320 if ((!psw_extint_disabled(vcpu)) &&
321 (vcpu->arch.sie_block->gcr[0] & 0x800ul))
322 rc = 1;
325 return rc;
328 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
330 return 0;
333 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
335 u64 now, sltime;
336 DECLARE_WAITQUEUE(wait, current);
338 vcpu->stat.exit_wait_state++;
339 if (kvm_cpu_has_interrupt(vcpu))
340 return 0;
342 __set_cpu_idle(vcpu);
343 spin_lock_bh(&vcpu->arch.local_int.lock);
344 vcpu->arch.local_int.timer_due = 0;
345 spin_unlock_bh(&vcpu->arch.local_int.lock);
347 if (psw_interrupts_disabled(vcpu)) {
348 VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
349 __unset_cpu_idle(vcpu);
350 return -EOPNOTSUPP; /* disabled wait */
353 if (psw_extint_disabled(vcpu) ||
354 (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))) {
355 VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
356 goto no_timer;
359 now = get_clock() + vcpu->arch.sie_block->epoch;
360 if (vcpu->arch.sie_block->ckc < now) {
361 __unset_cpu_idle(vcpu);
362 return 0;
365 sltime = ((vcpu->arch.sie_block->ckc - now)*125)>>9;
367 hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
368 VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
369 no_timer:
370 spin_lock(&vcpu->arch.local_int.float_int->lock);
371 spin_lock_bh(&vcpu->arch.local_int.lock);
372 add_wait_queue(&vcpu->arch.local_int.wq, &wait);
373 while (list_empty(&vcpu->arch.local_int.list) &&
374 list_empty(&vcpu->arch.local_int.float_int->list) &&
375 (!vcpu->arch.local_int.timer_due) &&
376 !signal_pending(current)) {
377 set_current_state(TASK_INTERRUPTIBLE);
378 spin_unlock_bh(&vcpu->arch.local_int.lock);
379 spin_unlock(&vcpu->arch.local_int.float_int->lock);
380 vcpu_put(vcpu);
381 schedule();
382 vcpu_load(vcpu);
383 spin_lock(&vcpu->arch.local_int.float_int->lock);
384 spin_lock_bh(&vcpu->arch.local_int.lock);
386 __unset_cpu_idle(vcpu);
387 __set_current_state(TASK_RUNNING);
388 remove_wait_queue(&vcpu->arch.local_int.wq, &wait);
389 spin_unlock_bh(&vcpu->arch.local_int.lock);
390 spin_unlock(&vcpu->arch.local_int.float_int->lock);
391 hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
392 return 0;
395 void kvm_s390_tasklet(unsigned long parm)
397 struct kvm_vcpu *vcpu = (struct kvm_vcpu *) parm;
399 spin_lock(&vcpu->arch.local_int.lock);
400 vcpu->arch.local_int.timer_due = 1;
401 if (waitqueue_active(&vcpu->arch.local_int.wq))
402 wake_up_interruptible(&vcpu->arch.local_int.wq);
403 spin_unlock(&vcpu->arch.local_int.lock);
407 * low level hrtimer wake routine. Because this runs in hardirq context
408 * we schedule a tasklet to do the real work.
410 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
412 struct kvm_vcpu *vcpu;
414 vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer);
415 tasklet_schedule(&vcpu->arch.tasklet);
417 return HRTIMER_NORESTART;
420 void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
422 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
423 struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
424 struct kvm_s390_interrupt_info *n, *inti = NULL;
425 int deliver;
427 __reset_intercept_indicators(vcpu);
428 if (atomic_read(&li->active)) {
429 do {
430 deliver = 0;
431 spin_lock_bh(&li->lock);
432 list_for_each_entry_safe(inti, n, &li->list, list) {
433 if (__interrupt_is_deliverable(vcpu, inti)) {
434 list_del(&inti->list);
435 deliver = 1;
436 break;
438 __set_intercept_indicator(vcpu, inti);
440 if (list_empty(&li->list))
441 atomic_set(&li->active, 0);
442 spin_unlock_bh(&li->lock);
443 if (deliver) {
444 __do_deliver_interrupt(vcpu, inti);
445 kfree(inti);
447 } while (deliver);
450 if ((vcpu->arch.sie_block->ckc <
451 get_clock() + vcpu->arch.sie_block->epoch))
452 __try_deliver_ckc_interrupt(vcpu);
454 if (atomic_read(&fi->active)) {
455 do {
456 deliver = 0;
457 spin_lock(&fi->lock);
458 list_for_each_entry_safe(inti, n, &fi->list, list) {
459 if (__interrupt_is_deliverable(vcpu, inti)) {
460 list_del(&inti->list);
461 deliver = 1;
462 break;
464 __set_intercept_indicator(vcpu, inti);
466 if (list_empty(&fi->list))
467 atomic_set(&fi->active, 0);
468 spin_unlock(&fi->lock);
469 if (deliver) {
470 __do_deliver_interrupt(vcpu, inti);
471 kfree(inti);
473 } while (deliver);
477 int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
479 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
480 struct kvm_s390_interrupt_info *inti;
482 inti = kzalloc(sizeof(*inti), GFP_KERNEL);
483 if (!inti)
484 return -ENOMEM;
486 inti->type = KVM_S390_PROGRAM_INT;
487 inti->pgm.code = code;
489 VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
490 spin_lock_bh(&li->lock);
491 list_add(&inti->list, &li->list);
492 atomic_set(&li->active, 1);
493 BUG_ON(waitqueue_active(&li->wq));
494 spin_unlock_bh(&li->lock);
495 return 0;
498 int kvm_s390_inject_vm(struct kvm *kvm,
499 struct kvm_s390_interrupt *s390int)
501 struct kvm_s390_local_interrupt *li;
502 struct kvm_s390_float_interrupt *fi;
503 struct kvm_s390_interrupt_info *inti;
504 int sigcpu;
506 inti = kzalloc(sizeof(*inti), GFP_KERNEL);
507 if (!inti)
508 return -ENOMEM;
510 switch (s390int->type) {
511 case KVM_S390_INT_VIRTIO:
512 VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx",
513 s390int->parm, s390int->parm64);
514 inti->type = s390int->type;
515 inti->ext.ext_params = s390int->parm;
516 inti->ext.ext_params2 = s390int->parm64;
517 break;
518 case KVM_S390_INT_SERVICE:
519 VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
520 inti->type = s390int->type;
521 inti->ext.ext_params = s390int->parm;
522 break;
523 case KVM_S390_PROGRAM_INT:
524 case KVM_S390_SIGP_STOP:
525 case KVM_S390_INT_EMERGENCY:
526 default:
527 kfree(inti);
528 return -EINVAL;
531 mutex_lock(&kvm->lock);
532 fi = &kvm->arch.float_int;
533 spin_lock(&fi->lock);
534 list_add_tail(&inti->list, &fi->list);
535 atomic_set(&fi->active, 1);
536 sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
537 if (sigcpu == KVM_MAX_VCPUS) {
538 do {
539 sigcpu = fi->next_rr_cpu++;
540 if (sigcpu == KVM_MAX_VCPUS)
541 sigcpu = fi->next_rr_cpu = 0;
542 } while (fi->local_int[sigcpu] == NULL);
544 li = fi->local_int[sigcpu];
545 spin_lock_bh(&li->lock);
546 atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
547 if (waitqueue_active(&li->wq))
548 wake_up_interruptible(&li->wq);
549 spin_unlock_bh(&li->lock);
550 spin_unlock(&fi->lock);
551 mutex_unlock(&kvm->lock);
552 return 0;
555 int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
556 struct kvm_s390_interrupt *s390int)
558 struct kvm_s390_local_interrupt *li;
559 struct kvm_s390_interrupt_info *inti;
561 inti = kzalloc(sizeof(*inti), GFP_KERNEL);
562 if (!inti)
563 return -ENOMEM;
565 switch (s390int->type) {
566 case KVM_S390_PROGRAM_INT:
567 if (s390int->parm & 0xffff0000) {
568 kfree(inti);
569 return -EINVAL;
571 inti->type = s390int->type;
572 inti->pgm.code = s390int->parm;
573 VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)",
574 s390int->parm);
575 break;
576 case KVM_S390_SIGP_SET_PREFIX:
577 inti->prefix.address = s390int->parm;
578 inti->type = s390int->type;
579 VCPU_EVENT(vcpu, 3, "inject: set prefix to %x (from user)",
580 s390int->parm);
581 break;
582 case KVM_S390_SIGP_STOP:
583 case KVM_S390_RESTART:
584 case KVM_S390_INT_EMERGENCY:
585 VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type);
586 inti->type = s390int->type;
587 break;
588 case KVM_S390_INT_VIRTIO:
589 case KVM_S390_INT_SERVICE:
590 default:
591 kfree(inti);
592 return -EINVAL;
595 mutex_lock(&vcpu->kvm->lock);
596 li = &vcpu->arch.local_int;
597 spin_lock_bh(&li->lock);
598 if (inti->type == KVM_S390_PROGRAM_INT)
599 list_add(&inti->list, &li->list);
600 else
601 list_add_tail(&inti->list, &li->list);
602 atomic_set(&li->active, 1);
603 if (inti->type == KVM_S390_SIGP_STOP)
604 li->action_bits |= ACTION_STOP_ON_STOP;
605 atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
606 if (waitqueue_active(&li->wq))
607 wake_up_interruptible(&vcpu->arch.local_int.wq);
608 spin_unlock_bh(&li->lock);
609 mutex_unlock(&vcpu->kvm->lock);
610 return 0;