fcd1ed8015c1c2d3b4f4dbdca4f202ffc2dd281a
[sfrench/cifs-2.6.git] / arch / s390 / kvm / interrupt.c
1 /*
2  * interrupt.c - handling kvm guest interrupts
3  *
4  * Copyright IBM Corp. 2008
5  *
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.
9  *
10  *    Author(s): Carsten Otte <cotte@de.ibm.com>
11  */
12
13 #include <asm/lowcore.h>
14 #include <asm/uaccess.h>
15 #include <linux/kvm_host.h>
16 #include "kvm-s390.h"
17 #include "gaccess.h"
18
19 static int psw_extint_disabled(struct kvm_vcpu *vcpu)
20 {
21         return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
22 }
23
24 static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
25 {
26         if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
27             (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) ||
28             (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT))
29                 return 0;
30         return 1;
31 }
32
33 static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
34                                       struct interrupt_info *inti)
35 {
36         switch (inti->type) {
37         case KVM_S390_INT_EMERGENCY:
38                 if (psw_extint_disabled(vcpu))
39                         return 0;
40                 if (vcpu->arch.sie_block->gcr[0] & 0x4000ul)
41                         return 1;
42                 return 0;
43         case KVM_S390_INT_SERVICE:
44                 if (psw_extint_disabled(vcpu))
45                         return 0;
46                 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
47                         return 1;
48                 return 0;
49         case KVM_S390_INT_VIRTIO:
50                 if (psw_extint_disabled(vcpu))
51                         return 0;
52                 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
53                         return 1;
54                 return 0;
55         case KVM_S390_PROGRAM_INT:
56         case KVM_S390_SIGP_STOP:
57         case KVM_S390_SIGP_SET_PREFIX:
58         case KVM_S390_RESTART:
59                 return 1;
60         default:
61                 BUG();
62         }
63         return 0;
64 }
65
66 static void __set_cpu_idle(struct kvm_vcpu *vcpu)
67 {
68         BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
69         atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
70         set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
71 }
72
73 static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
74 {
75         BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
76         atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
77         clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
78 }
79
80 static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
81 {
82         atomic_clear_mask(CPUSTAT_ECALL_PEND |
83                 CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
84                 &vcpu->arch.sie_block->cpuflags);
85         vcpu->arch.sie_block->lctl = 0x0000;
86 }
87
88 static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
89 {
90         atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags);
91 }
92
93 static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
94                                       struct interrupt_info *inti)
95 {
96         switch (inti->type) {
97         case KVM_S390_INT_EMERGENCY:
98         case KVM_S390_INT_SERVICE:
99         case KVM_S390_INT_VIRTIO:
100                 if (psw_extint_disabled(vcpu))
101                         __set_cpuflag(vcpu, CPUSTAT_EXT_INT);
102                 else
103                         vcpu->arch.sie_block->lctl |= LCTL_CR0;
104                 break;
105         case KVM_S390_SIGP_STOP:
106                 __set_cpuflag(vcpu, CPUSTAT_STOP_INT);
107                 break;
108         default:
109                 BUG();
110         }
111 }
112
113 static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
114                                    struct interrupt_info *inti)
115 {
116         const unsigned short table[] = { 2, 4, 4, 6 };
117         int rc, exception = 0;
118
119         switch (inti->type) {
120         case KVM_S390_INT_EMERGENCY:
121                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg");
122                 vcpu->stat.deliver_emergency_signal++;
123                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1201);
124                 if (rc == -EFAULT)
125                         exception = 1;
126
127                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
128                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
129                 if (rc == -EFAULT)
130                         exception = 1;
131
132                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
133                         __LC_EXT_NEW_PSW, sizeof(psw_t));
134                 if (rc == -EFAULT)
135                         exception = 1;
136                 break;
137
138         case KVM_S390_INT_SERVICE:
139                 VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x",
140                            inti->ext.ext_params);
141                 vcpu->stat.deliver_service_signal++;
142                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2401);
143                 if (rc == -EFAULT)
144                         exception = 1;
145
146                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
147                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
148                 if (rc == -EFAULT)
149                         exception = 1;
150
151                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
152                         __LC_EXT_NEW_PSW, sizeof(psw_t));
153                 if (rc == -EFAULT)
154                         exception = 1;
155
156                 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
157                 if (rc == -EFAULT)
158                         exception = 1;
159                 break;
160
161         case KVM_S390_INT_VIRTIO:
162                 VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%lx",
163                            inti->ext.ext_params, inti->ext.ext_params2);
164                 vcpu->stat.deliver_virtio_interrupt++;
165                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2603);
166                 if (rc == -EFAULT)
167                         exception = 1;
168
169                 rc = put_guest_u16(vcpu, __LC_CPU_ADDRESS, 0x0d00);
170                 if (rc == -EFAULT)
171                         exception = 1;
172
173                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
174                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
175                 if (rc == -EFAULT)
176                         exception = 1;
177
178                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
179                         __LC_EXT_NEW_PSW, sizeof(psw_t));
180                 if (rc == -EFAULT)
181                         exception = 1;
182
183                 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
184                 if (rc == -EFAULT)
185                         exception = 1;
186
187                 rc = put_guest_u64(vcpu, __LC_PFAULT_INTPARM,
188                         inti->ext.ext_params2);
189                 if (rc == -EFAULT)
190                         exception = 1;
191                 break;
192
193         case KVM_S390_SIGP_STOP:
194                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop");
195                 vcpu->stat.deliver_stop_signal++;
196                 __set_intercept_indicator(vcpu, inti);
197                 break;
198
199         case KVM_S390_SIGP_SET_PREFIX:
200                 VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x",
201                            inti->prefix.address);
202                 vcpu->stat.deliver_prefix_signal++;
203                 vcpu->arch.sie_block->prefix = inti->prefix.address;
204                 vcpu->arch.sie_block->ihcpu = 0xffff;
205                 break;
206
207         case KVM_S390_RESTART:
208                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart");
209                 vcpu->stat.deliver_restart_signal++;
210                 rc = copy_to_guest(vcpu, offsetof(struct _lowcore,
211                   restart_old_psw), &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
212                 if (rc == -EFAULT)
213                         exception = 1;
214
215                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
216                         offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
217                 if (rc == -EFAULT)
218                         exception = 1;
219                 break;
220
221         case KVM_S390_PROGRAM_INT:
222                 VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x",
223                            inti->pgm.code,
224                            table[vcpu->arch.sie_block->ipa >> 14]);
225                 vcpu->stat.deliver_program_int++;
226                 rc = put_guest_u16(vcpu, __LC_PGM_INT_CODE, inti->pgm.code);
227                 if (rc == -EFAULT)
228                         exception = 1;
229
230                 rc = put_guest_u16(vcpu, __LC_PGM_ILC,
231                         table[vcpu->arch.sie_block->ipa >> 14]);
232                 if (rc == -EFAULT)
233                         exception = 1;
234
235                 rc = copy_to_guest(vcpu, __LC_PGM_OLD_PSW,
236                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
237                 if (rc == -EFAULT)
238                         exception = 1;
239
240                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
241                         __LC_PGM_NEW_PSW, sizeof(psw_t));
242                 if (rc == -EFAULT)
243                         exception = 1;
244                 break;
245
246         default:
247                 BUG();
248         }
249
250         if (exception) {
251                 VCPU_EVENT(vcpu, 1, "%s", "program exception while delivering"
252                            " interrupt");
253                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
254                 if (inti->type == KVM_S390_PROGRAM_INT) {
255                         printk(KERN_WARNING "kvm: recursive program check\n");
256                         BUG();
257                 }
258         }
259 }
260
261 static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
262 {
263         int rc, exception = 0;
264
265         if (psw_extint_disabled(vcpu))
266                 return 0;
267         if (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))
268                 return 0;
269         rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1004);
270         if (rc == -EFAULT)
271                 exception = 1;
272         rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
273                  &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
274         if (rc == -EFAULT)
275                 exception = 1;
276         rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
277                 __LC_EXT_NEW_PSW, sizeof(psw_t));
278         if (rc == -EFAULT)
279                 exception = 1;
280
281         if (exception) {
282                 VCPU_EVENT(vcpu, 1, "%s", "program exception while delivering" \
283                            " ckc interrupt");
284                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
285                 return 0;
286         }
287
288         return 1;
289 }
290
291 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
292 {
293         struct local_interrupt *li = &vcpu->arch.local_int;
294         struct float_interrupt *fi = vcpu->arch.local_int.float_int;
295         struct interrupt_info  *inti;
296         int rc = 0;
297
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;
304                         }
305                 spin_unlock_bh(&li->lock);
306         }
307
308         if ((!rc) && atomic_read(&fi->active)) {
309                 spin_lock_bh(&fi->lock);
310                 list_for_each_entry(inti, &fi->list, list)
311                         if (__interrupt_is_deliverable(vcpu, inti)) {
312                                 rc = 1;
313                                 break;
314                         }
315                 spin_unlock_bh(&fi->lock);
316         }
317
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;
323         }
324
325         return rc;
326 }
327
328 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
329 {
330         return 0;
331 }
332
333 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
334 {
335         u64 now, sltime;
336         DECLARE_WAITQUEUE(wait, current);
337
338         vcpu->stat.exit_wait_state++;
339         if (kvm_cpu_has_interrupt(vcpu))
340                 return 0;
341
342         if (psw_interrupts_disabled(vcpu)) {
343                 VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
344                 __unset_cpu_idle(vcpu);
345                 return -ENOTSUPP; /* disabled wait */
346         }
347
348         if (psw_extint_disabled(vcpu) ||
349             (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))) {
350                 VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
351                 goto no_timer;
352         }
353
354         now = get_clock() + vcpu->arch.sie_block->epoch;
355         if (vcpu->arch.sie_block->ckc < now) {
356                 __unset_cpu_idle(vcpu);
357                 return 0;
358         }
359
360         sltime = (vcpu->arch.sie_block->ckc - now) / (0xf4240000ul / HZ) + 1;
361
362         vcpu->arch.ckc_timer.expires = jiffies + sltime;
363
364         add_timer(&vcpu->arch.ckc_timer);
365         VCPU_EVENT(vcpu, 5, "enabled wait timer:%lx jiffies", sltime);
366 no_timer:
367         spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
368         spin_lock_bh(&vcpu->arch.local_int.lock);
369         __set_cpu_idle(vcpu);
370         vcpu->arch.local_int.timer_due = 0;
371         add_wait_queue(&vcpu->arch.local_int.wq, &wait);
372         while (list_empty(&vcpu->arch.local_int.list) &&
373                 list_empty(&vcpu->arch.local_int.float_int->list) &&
374                 (!vcpu->arch.local_int.timer_due) &&
375                 !signal_pending(current)) {
376                 set_current_state(TASK_INTERRUPTIBLE);
377                 spin_unlock_bh(&vcpu->arch.local_int.lock);
378                 spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
379                 vcpu_put(vcpu);
380                 schedule();
381                 vcpu_load(vcpu);
382                 spin_lock_bh(&vcpu->arch.local_int.float_int->lock);
383                 spin_lock_bh(&vcpu->arch.local_int.lock);
384         }
385         __unset_cpu_idle(vcpu);
386         __set_current_state(TASK_RUNNING);
387         remove_wait_queue(&vcpu->wq, &wait);
388         spin_unlock_bh(&vcpu->arch.local_int.lock);
389         spin_unlock_bh(&vcpu->arch.local_int.float_int->lock);
390         del_timer(&vcpu->arch.ckc_timer);
391         return 0;
392 }
393
394 void kvm_s390_idle_wakeup(unsigned long data)
395 {
396         struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
397
398         spin_lock_bh(&vcpu->arch.local_int.lock);
399         vcpu->arch.local_int.timer_due = 1;
400         if (waitqueue_active(&vcpu->arch.local_int.wq))
401                 wake_up_interruptible(&vcpu->arch.local_int.wq);
402         spin_unlock_bh(&vcpu->arch.local_int.lock);
403 }
404
405
406 void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
407 {
408         struct local_interrupt *li = &vcpu->arch.local_int;
409         struct float_interrupt *fi = vcpu->arch.local_int.float_int;
410         struct interrupt_info  *n, *inti = NULL;
411         int deliver;
412
413         __reset_intercept_indicators(vcpu);
414         if (atomic_read(&li->active)) {
415                 do {
416                         deliver = 0;
417                         spin_lock_bh(&li->lock);
418                         list_for_each_entry_safe(inti, n, &li->list, list) {
419                                 if (__interrupt_is_deliverable(vcpu, inti)) {
420                                         list_del(&inti->list);
421                                         deliver = 1;
422                                         break;
423                                 }
424                                 __set_intercept_indicator(vcpu, inti);
425                         }
426                         if (list_empty(&li->list))
427                                 atomic_set(&li->active, 0);
428                         spin_unlock_bh(&li->lock);
429                         if (deliver) {
430                                 __do_deliver_interrupt(vcpu, inti);
431                                 kfree(inti);
432                         }
433                 } while (deliver);
434         }
435
436         if ((vcpu->arch.sie_block->ckc <
437                 get_clock() + vcpu->arch.sie_block->epoch))
438                 __try_deliver_ckc_interrupt(vcpu);
439
440         if (atomic_read(&fi->active)) {
441                 do {
442                         deliver = 0;
443                         spin_lock_bh(&fi->lock);
444                         list_for_each_entry_safe(inti, n, &fi->list, list) {
445                                 if (__interrupt_is_deliverable(vcpu, inti)) {
446                                         list_del(&inti->list);
447                                         deliver = 1;
448                                         break;
449                                 }
450                                 __set_intercept_indicator(vcpu, inti);
451                         }
452                         if (list_empty(&fi->list))
453                                 atomic_set(&fi->active, 0);
454                         spin_unlock_bh(&fi->lock);
455                         if (deliver) {
456                                 __do_deliver_interrupt(vcpu, inti);
457                                 kfree(inti);
458                         }
459                 } while (deliver);
460         }
461 }
462
463 int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
464 {
465         struct local_interrupt *li = &vcpu->arch.local_int;
466         struct interrupt_info *inti;
467
468         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
469         if (!inti)
470                 return -ENOMEM;
471
472         inti->type = KVM_S390_PROGRAM_INT;;
473         inti->pgm.code = code;
474
475         VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
476         spin_lock_bh(&li->lock);
477         list_add(&inti->list, &li->list);
478         atomic_set(&li->active, 1);
479         BUG_ON(waitqueue_active(&li->wq));
480         spin_unlock_bh(&li->lock);
481         return 0;
482 }
483
484 int kvm_s390_inject_vm(struct kvm *kvm,
485                        struct kvm_s390_interrupt *s390int)
486 {
487         struct local_interrupt *li;
488         struct float_interrupt *fi;
489         struct interrupt_info *inti;
490         int sigcpu;
491
492         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
493         if (!inti)
494                 return -ENOMEM;
495
496         switch (s390int->type) {
497         case KVM_S390_INT_VIRTIO:
498                 VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%lx",
499                          s390int->parm, s390int->parm64);
500                 inti->type = s390int->type;
501                 inti->ext.ext_params = s390int->parm;
502                 inti->ext.ext_params2 = s390int->parm64;
503                 break;
504         case KVM_S390_INT_SERVICE:
505                 VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
506                 inti->type = s390int->type;
507                 inti->ext.ext_params = s390int->parm;
508                 break;
509         case KVM_S390_PROGRAM_INT:
510         case KVM_S390_SIGP_STOP:
511         case KVM_S390_INT_EMERGENCY:
512         default:
513                 kfree(inti);
514                 return -EINVAL;
515         }
516
517         mutex_lock(&kvm->lock);
518         fi = &kvm->arch.float_int;
519         spin_lock_bh(&fi->lock);
520         list_add_tail(&inti->list, &fi->list);
521         atomic_set(&fi->active, 1);
522         sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
523         if (sigcpu == KVM_MAX_VCPUS) {
524                 do {
525                         sigcpu = fi->next_rr_cpu++;
526                         if (sigcpu == KVM_MAX_VCPUS)
527                                 sigcpu = fi->next_rr_cpu = 0;
528                 } while (fi->local_int[sigcpu] == NULL);
529         }
530         li = fi->local_int[sigcpu];
531         spin_lock_bh(&li->lock);
532         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
533         if (waitqueue_active(&li->wq))
534                 wake_up_interruptible(&li->wq);
535         spin_unlock_bh(&li->lock);
536         spin_unlock_bh(&fi->lock);
537         mutex_unlock(&kvm->lock);
538         return 0;
539 }
540
541 int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
542                          struct kvm_s390_interrupt *s390int)
543 {
544         struct local_interrupt *li;
545         struct interrupt_info *inti;
546
547         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
548         if (!inti)
549                 return -ENOMEM;
550
551         switch (s390int->type) {
552         case KVM_S390_PROGRAM_INT:
553                 if (s390int->parm & 0xffff0000) {
554                         kfree(inti);
555                         return -EINVAL;
556                 }
557                 inti->type = s390int->type;
558                 inti->pgm.code = s390int->parm;
559                 VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)",
560                            s390int->parm);
561                 break;
562         case KVM_S390_SIGP_STOP:
563         case KVM_S390_RESTART:
564         case KVM_S390_SIGP_SET_PREFIX:
565         case KVM_S390_INT_EMERGENCY:
566                 VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type);
567                 inti->type = s390int->type;
568                 break;
569         case KVM_S390_INT_VIRTIO:
570         case KVM_S390_INT_SERVICE:
571         default:
572                 kfree(inti);
573                 return -EINVAL;
574         }
575
576         mutex_lock(&vcpu->kvm->lock);
577         li = &vcpu->arch.local_int;
578         spin_lock_bh(&li->lock);
579         if (inti->type == KVM_S390_PROGRAM_INT)
580                 list_add(&inti->list, &li->list);
581         else
582                 list_add_tail(&inti->list, &li->list);
583         atomic_set(&li->active, 1);
584         if (inti->type == KVM_S390_SIGP_STOP)
585                 li->action_bits |= ACTION_STOP_ON_STOP;
586         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
587         if (waitqueue_active(&li->wq))
588                 wake_up_interruptible(&vcpu->arch.local_int.wq);
589         spin_unlock_bh(&li->lock);
590         mutex_unlock(&vcpu->kvm->lock);
591         return 0;
592 }