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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * in-kernel handling for sie intercepts
4 *
5 * Copyright IBM Corp. 2008, 2020
6 *
7 * Author(s): Carsten Otte <cotte@de.ibm.com>
8 * Christian Borntraeger <borntraeger@de.ibm.com>
9 */
10
11#include <linux/kvm_host.h>
12#include <linux/errno.h>
13#include <linux/pagemap.h>
14
15#include <asm/asm-offsets.h>
16#include <asm/irq.h>
17#include <asm/sysinfo.h>
18#include <asm/uv.h>
19
20#include "kvm-s390.h"
21#include "gaccess.h"
22#include "trace.h"
23#include "trace-s390.h"
24
25u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
26{
27 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
28 u8 ilen = 0;
29
30 switch (vcpu->arch.sie_block->icptcode) {
31 case ICPT_INST:
32 case ICPT_INSTPROGI:
33 case ICPT_OPEREXC:
34 case ICPT_PARTEXEC:
35 case ICPT_IOINST:
36 /* instruction only stored for these icptcodes */
37 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8);
38 /* Use the length of the EXECUTE instruction if necessary */
39 if (sie_block->icptstatus & 1) {
40 ilen = (sie_block->icptstatus >> 4) & 0x6;
41 if (!ilen)
42 ilen = 4;
43 }
44 break;
45 case ICPT_PROGI:
46 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */
47 ilen = vcpu->arch.sie_block->pgmilc & 0x6;
48 break;
49 }
50 return ilen;
51}
52
53static int handle_stop(struct kvm_vcpu *vcpu)
54{
55 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
56 int rc = 0;
57 uint8_t flags, stop_pending;
58
59 vcpu->stat.exit_stop_request++;
60
61 /* delay the stop if any non-stop irq is pending */
62 if (kvm_s390_vcpu_has_irq(vcpu, 1))
63 return 0;
64
65 /* avoid races with the injection/SIGP STOP code */
66 spin_lock(&li->lock);
67 flags = li->irq.stop.flags;
68 stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
69 spin_unlock(&li->lock);
70
71 trace_kvm_s390_stop_request(stop_pending, flags);
72 if (!stop_pending)
73 return 0;
74
75 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
76 rc = kvm_s390_vcpu_store_status(vcpu,
77 KVM_S390_STORE_STATUS_NOADDR);
78 if (rc)
79 return rc;
80 }
81
82 /*
83 * no need to check the return value of vcpu_stop as it can only have
84 * an error for protvirt, but protvirt means user cpu state
85 */
86 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
87 kvm_s390_vcpu_stop(vcpu);
88 return -EOPNOTSUPP;
89}
90
91static int handle_validity(struct kvm_vcpu *vcpu)
92{
93 int viwhy = vcpu->arch.sie_block->ipb >> 16;
94
95 vcpu->stat.exit_validity++;
96 trace_kvm_s390_intercept_validity(vcpu, viwhy);
97 KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy,
98 current->pid, vcpu->kvm);
99
100 /* do not warn on invalid runtime instrumentation mode */
101 WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n",
102 viwhy);
103 return -EINVAL;
104}
105
106static int handle_instruction(struct kvm_vcpu *vcpu)
107{
108 vcpu->stat.exit_instruction++;
109 trace_kvm_s390_intercept_instruction(vcpu,
110 vcpu->arch.sie_block->ipa,
111 vcpu->arch.sie_block->ipb);
112
113 switch (vcpu->arch.sie_block->ipa >> 8) {
114 case 0x01:
115 return kvm_s390_handle_01(vcpu);
116 case 0x82:
117 return kvm_s390_handle_lpsw(vcpu);
118 case 0x83:
119 return kvm_s390_handle_diag(vcpu);
120 case 0xaa:
121 return kvm_s390_handle_aa(vcpu);
122 case 0xae:
123 return kvm_s390_handle_sigp(vcpu);
124 case 0xb2:
125 return kvm_s390_handle_b2(vcpu);
126 case 0xb6:
127 return kvm_s390_handle_stctl(vcpu);
128 case 0xb7:
129 return kvm_s390_handle_lctl(vcpu);
130 case 0xb9:
131 return kvm_s390_handle_b9(vcpu);
132 case 0xe3:
133 return kvm_s390_handle_e3(vcpu);
134 case 0xe5:
135 return kvm_s390_handle_e5(vcpu);
136 case 0xeb:
137 return kvm_s390_handle_eb(vcpu);
138 default:
139 return -EOPNOTSUPP;
140 }
141}
142
143static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)
144{
145 struct kvm_s390_pgm_info pgm_info = {
146 .code = vcpu->arch.sie_block->iprcc,
147 /* the PSW has already been rewound */
148 .flags = KVM_S390_PGM_FLAGS_NO_REWIND,
149 };
150
151 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
152 case PGM_AFX_TRANSLATION:
153 case PGM_ASX_TRANSLATION:
154 case PGM_EX_TRANSLATION:
155 case PGM_LFX_TRANSLATION:
156 case PGM_LSTE_SEQUENCE:
157 case PGM_LSX_TRANSLATION:
158 case PGM_LX_TRANSLATION:
159 case PGM_PRIMARY_AUTHORITY:
160 case PGM_SECONDARY_AUTHORITY:
161 case PGM_SPACE_SWITCH:
162 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
163 break;
164 case PGM_ALEN_TRANSLATION:
165 case PGM_ALE_SEQUENCE:
166 case PGM_ASTE_INSTANCE:
167 case PGM_ASTE_SEQUENCE:
168 case PGM_ASTE_VALIDITY:
169 case PGM_EXTENDED_AUTHORITY:
170 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
171 break;
172 case PGM_ASCE_TYPE:
173 case PGM_PAGE_TRANSLATION:
174 case PGM_REGION_FIRST_TRANS:
175 case PGM_REGION_SECOND_TRANS:
176 case PGM_REGION_THIRD_TRANS:
177 case PGM_SEGMENT_TRANSLATION:
178 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
179 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
180 pgm_info.op_access_id = vcpu->arch.sie_block->oai;
181 break;
182 case PGM_MONITOR:
183 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn;
184 pgm_info.mon_code = vcpu->arch.sie_block->tecmc;
185 break;
186 case PGM_VECTOR_PROCESSING:
187 case PGM_DATA:
188 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc;
189 break;
190 case PGM_PROTECTION:
191 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
192 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
193 break;
194 default:
195 break;
196 }
197
198 if (vcpu->arch.sie_block->iprcc & PGM_PER) {
199 pgm_info.per_code = vcpu->arch.sie_block->perc;
200 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid;
201 pgm_info.per_address = vcpu->arch.sie_block->peraddr;
202 pgm_info.per_access_id = vcpu->arch.sie_block->peraid;
203 }
204 return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
205}
206
207/*
208 * restore ITDB to program-interruption TDB in guest lowcore
209 * and set TX abort indication if required
210*/
211static int handle_itdb(struct kvm_vcpu *vcpu)
212{
213 struct kvm_s390_itdb *itdb;
214 int rc;
215
216 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
217 return 0;
218 if (current->thread.per_flags & PER_FLAG_NO_TE)
219 return 0;
220 itdb = phys_to_virt(vcpu->arch.sie_block->itdba);
221 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
222 if (rc)
223 return rc;
224 memset(itdb, 0, sizeof(*itdb));
225
226 return 0;
227}
228
229#define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
230
231static int handle_prog(struct kvm_vcpu *vcpu)
232{
233 psw_t psw;
234 int rc;
235
236 vcpu->stat.exit_program_interruption++;
237
238 /*
239 * Intercept 8 indicates a loop of specification exceptions
240 * for protected guests.
241 */
242 if (kvm_s390_pv_cpu_is_protected(vcpu))
243 return -EOPNOTSUPP;
244
245 if (guestdbg_enabled(vcpu) && per_event(vcpu)) {
246 rc = kvm_s390_handle_per_event(vcpu);
247 if (rc)
248 return rc;
249 /* the interrupt might have been filtered out completely */
250 if (vcpu->arch.sie_block->iprcc == 0)
251 return 0;
252 }
253
254 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
255 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
256 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
257 if (rc)
258 return rc;
259 /* Avoid endless loops of specification exceptions */
260 if (!is_valid_psw(&psw))
261 return -EOPNOTSUPP;
262 }
263 rc = handle_itdb(vcpu);
264 if (rc)
265 return rc;
266
267 return inject_prog_on_prog_intercept(vcpu);
268}
269
270/**
271 * handle_external_interrupt - used for external interruption interceptions
272 * @vcpu: virtual cpu
273 *
274 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if
275 * the new PSW does not have external interrupts disabled. In the first case,
276 * we've got to deliver the interrupt manually, and in the second case, we
277 * drop to userspace to handle the situation there.
278 */
279static int handle_external_interrupt(struct kvm_vcpu *vcpu)
280{
281 u16 eic = vcpu->arch.sie_block->eic;
282 struct kvm_s390_irq irq;
283 psw_t newpsw;
284 int rc;
285
286 vcpu->stat.exit_external_interrupt++;
287
288 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
289 if (rc)
290 return rc;
291 /* We can not handle clock comparator or timer interrupt with bad PSW */
292 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
293 (newpsw.mask & PSW_MASK_EXT))
294 return -EOPNOTSUPP;
295
296 switch (eic) {
297 case EXT_IRQ_CLK_COMP:
298 irq.type = KVM_S390_INT_CLOCK_COMP;
299 break;
300 case EXT_IRQ_CPU_TIMER:
301 irq.type = KVM_S390_INT_CPU_TIMER;
302 break;
303 case EXT_IRQ_EXTERNAL_CALL:
304 irq.type = KVM_S390_INT_EXTERNAL_CALL;
305 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
306 rc = kvm_s390_inject_vcpu(vcpu, &irq);
307 /* ignore if another external call is already pending */
308 if (rc == -EBUSY)
309 return 0;
310 return rc;
311 default:
312 return -EOPNOTSUPP;
313 }
314
315 return kvm_s390_inject_vcpu(vcpu, &irq);
316}
317
318/**
319 * handle_mvpg_pei - Handle MOVE PAGE partial execution interception.
320 * @vcpu: virtual cpu
321 *
322 * This interception can only happen for guests with DAT disabled and
323 * addresses that are currently not mapped in the host. Thus we try to
324 * set up the mappings for the corresponding user pages here (or throw
325 * addressing exceptions in case of illegal guest addresses).
326 */
327static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
328{
329 unsigned long srcaddr, dstaddr;
330 int reg1, reg2, rc;
331
332 kvm_s390_get_regs_rre(vcpu, ®1, ®2);
333
334 /* Ensure that the source is paged-in, no actual access -> no key checking */
335 rc = guest_translate_address_with_key(vcpu, vcpu->run->s.regs.gprs[reg2],
336 reg2, &srcaddr, GACC_FETCH, 0);
337 if (rc)
338 return kvm_s390_inject_prog_cond(vcpu, rc);
339 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
340 if (rc != 0)
341 return rc;
342
343 /* Ensure that the source is paged-in, no actual access -> no key checking */
344 rc = guest_translate_address_with_key(vcpu, vcpu->run->s.regs.gprs[reg1],
345 reg1, &dstaddr, GACC_STORE, 0);
346 if (rc)
347 return kvm_s390_inject_prog_cond(vcpu, rc);
348 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
349 if (rc != 0)
350 return rc;
351
352 kvm_s390_retry_instr(vcpu);
353
354 return 0;
355}
356
357static int handle_partial_execution(struct kvm_vcpu *vcpu)
358{
359 vcpu->stat.exit_pei++;
360
361 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */
362 return handle_mvpg_pei(vcpu);
363 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */
364 return kvm_s390_handle_sigp_pei(vcpu);
365
366 return -EOPNOTSUPP;
367}
368
369/*
370 * Handle the sthyi instruction that provides the guest with system
371 * information, like current CPU resources available at each level of
372 * the machine.
373 */
374int handle_sthyi(struct kvm_vcpu *vcpu)
375{
376 int reg1, reg2, r = 0;
377 u64 code, addr, cc = 0, rc = 0;
378 struct sthyi_sctns *sctns = NULL;
379
380 if (!test_kvm_facility(vcpu->kvm, 74))
381 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
382
383 kvm_s390_get_regs_rre(vcpu, ®1, ®2);
384 code = vcpu->run->s.regs.gprs[reg1];
385 addr = vcpu->run->s.regs.gprs[reg2];
386
387 vcpu->stat.instruction_sthyi++;
388 VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr);
389 trace_kvm_s390_handle_sthyi(vcpu, code, addr);
390
391 if (reg1 == reg2 || reg1 & 1 || reg2 & 1)
392 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
393
394 if (code & 0xffff) {
395 cc = 3;
396 rc = 4;
397 goto out;
398 }
399
400 if (!kvm_s390_pv_cpu_is_protected(vcpu) && (addr & ~PAGE_MASK))
401 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
402
403 sctns = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
404 if (!sctns)
405 return -ENOMEM;
406
407 cc = sthyi_fill(sctns, &rc);
408
409out:
410 if (!cc) {
411 if (kvm_s390_pv_cpu_is_protected(vcpu)) {
412 memcpy(sida_addr(vcpu->arch.sie_block), sctns, PAGE_SIZE);
413 } else {
414 r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE);
415 if (r) {
416 free_page((unsigned long)sctns);
417 return kvm_s390_inject_prog_cond(vcpu, r);
418 }
419 }
420 }
421
422 free_page((unsigned long)sctns);
423 vcpu->run->s.regs.gprs[reg2 + 1] = rc;
424 kvm_s390_set_psw_cc(vcpu, cc);
425 return r;
426}
427
428static int handle_operexc(struct kvm_vcpu *vcpu)
429{
430 psw_t oldpsw, newpsw;
431 int rc;
432
433 vcpu->stat.exit_operation_exception++;
434 trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa,
435 vcpu->arch.sie_block->ipb);
436
437 if (vcpu->arch.sie_block->ipa == 0xb256)
438 return handle_sthyi(vcpu);
439
440 if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0)
441 return -EOPNOTSUPP;
442 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &newpsw, sizeof(psw_t));
443 if (rc)
444 return rc;
445 /*
446 * Avoid endless loops of operation exceptions, if the pgm new
447 * PSW will cause a new operation exception.
448 * The heuristic checks if the pgm new psw is within 6 bytes before
449 * the faulting psw address (with same DAT, AS settings) and the
450 * new psw is not a wait psw and the fault was not triggered by
451 * problem state.
452 */
453 oldpsw = vcpu->arch.sie_block->gpsw;
454 if (oldpsw.addr - newpsw.addr <= 6 &&
455 !(newpsw.mask & PSW_MASK_WAIT) &&
456 !(oldpsw.mask & PSW_MASK_PSTATE) &&
457 (newpsw.mask & PSW_MASK_ASC) == (oldpsw.mask & PSW_MASK_ASC) &&
458 (newpsw.mask & PSW_MASK_DAT) == (oldpsw.mask & PSW_MASK_DAT))
459 return -EOPNOTSUPP;
460
461 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
462}
463
464static int handle_pv_spx(struct kvm_vcpu *vcpu)
465{
466 u32 pref = *(u32 *)sida_addr(vcpu->arch.sie_block);
467
468 kvm_s390_set_prefix(vcpu, pref);
469 trace_kvm_s390_handle_prefix(vcpu, 1, pref);
470 return 0;
471}
472
473static int handle_pv_sclp(struct kvm_vcpu *vcpu)
474{
475 struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
476
477 spin_lock(&fi->lock);
478 /*
479 * 2 cases:
480 * a: an sccb answering interrupt was already pending or in flight.
481 * As the sccb value is not known we can simply set some value to
482 * trigger delivery of a saved SCCB. UV will then use its saved
483 * copy of the SCCB value.
484 * b: an error SCCB interrupt needs to be injected so we also inject
485 * a fake SCCB address. Firmware will use the proper one.
486 * This makes sure, that both errors and real sccb returns will only
487 * be delivered after a notification intercept (instruction has
488 * finished) but not after others.
489 */
490 fi->srv_signal.ext_params |= 0x43000;
491 set_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs);
492 clear_bit(IRQ_PEND_EXT_SERVICE, &fi->masked_irqs);
493 spin_unlock(&fi->lock);
494 return 0;
495}
496
497static int handle_pv_uvc(struct kvm_vcpu *vcpu)
498{
499 struct uv_cb_share *guest_uvcb = sida_addr(vcpu->arch.sie_block);
500 struct uv_cb_cts uvcb = {
501 .header.cmd = UVC_CMD_UNPIN_PAGE_SHARED,
502 .header.len = sizeof(uvcb),
503 .guest_handle = kvm_s390_pv_get_handle(vcpu->kvm),
504 .gaddr = guest_uvcb->paddr,
505 };
506 int rc;
507
508 if (guest_uvcb->header.cmd != UVC_CMD_REMOVE_SHARED_ACCESS) {
509 WARN_ONCE(1, "Unexpected notification intercept for UVC 0x%x\n",
510 guest_uvcb->header.cmd);
511 return 0;
512 }
513 rc = gmap_make_secure(vcpu->arch.gmap, uvcb.gaddr, &uvcb);
514 /*
515 * If the unpin did not succeed, the guest will exit again for the UVC
516 * and we will retry the unpin.
517 */
518 if (rc == -EINVAL)
519 return 0;
520 /*
521 * If we got -EAGAIN here, we simply return it. It will eventually
522 * get propagated all the way to userspace, which should then try
523 * again.
524 */
525 return rc;
526}
527
528static int handle_pv_notification(struct kvm_vcpu *vcpu)
529{
530 int ret;
531
532 if (vcpu->arch.sie_block->ipa == 0xb210)
533 return handle_pv_spx(vcpu);
534 if (vcpu->arch.sie_block->ipa == 0xb220)
535 return handle_pv_sclp(vcpu);
536 if (vcpu->arch.sie_block->ipa == 0xb9a4)
537 return handle_pv_uvc(vcpu);
538 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) {
539 /*
540 * Besides external call, other SIGP orders also cause a
541 * 108 (pv notify) intercept. In contrast to external call,
542 * these orders need to be emulated and hence the appropriate
543 * place to handle them is in handle_instruction().
544 * So first try kvm_s390_handle_sigp_pei() and if that isn't
545 * successful, go on with handle_instruction().
546 */
547 ret = kvm_s390_handle_sigp_pei(vcpu);
548 if (!ret)
549 return ret;
550 }
551
552 return handle_instruction(vcpu);
553}
554
555int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
556{
557 int rc, per_rc = 0;
558
559 if (kvm_is_ucontrol(vcpu->kvm))
560 return -EOPNOTSUPP;
561
562 switch (vcpu->arch.sie_block->icptcode) {
563 case ICPT_EXTREQ:
564 vcpu->stat.exit_external_request++;
565 return 0;
566 case ICPT_IOREQ:
567 vcpu->stat.exit_io_request++;
568 return 0;
569 case ICPT_INST:
570 rc = handle_instruction(vcpu);
571 break;
572 case ICPT_PROGI:
573 return handle_prog(vcpu);
574 case ICPT_EXTINT:
575 return handle_external_interrupt(vcpu);
576 case ICPT_WAIT:
577 return kvm_s390_handle_wait(vcpu);
578 case ICPT_VALIDITY:
579 return handle_validity(vcpu);
580 case ICPT_STOP:
581 return handle_stop(vcpu);
582 case ICPT_OPEREXC:
583 rc = handle_operexc(vcpu);
584 break;
585 case ICPT_PARTEXEC:
586 rc = handle_partial_execution(vcpu);
587 break;
588 case ICPT_KSS:
589 rc = kvm_s390_skey_check_enable(vcpu);
590 break;
591 case ICPT_MCHKREQ:
592 case ICPT_INT_ENABLE:
593 /*
594 * PSW bit 13 or a CR (0, 6, 14) changed and we might
595 * now be able to deliver interrupts. The pre-run code
596 * will take care of this.
597 */
598 rc = 0;
599 break;
600 case ICPT_PV_INSTR:
601 rc = handle_instruction(vcpu);
602 break;
603 case ICPT_PV_NOTIFY:
604 rc = handle_pv_notification(vcpu);
605 break;
606 case ICPT_PV_PREF:
607 rc = 0;
608 gmap_convert_to_secure(vcpu->arch.gmap,
609 kvm_s390_get_prefix(vcpu));
610 gmap_convert_to_secure(vcpu->arch.gmap,
611 kvm_s390_get_prefix(vcpu) + PAGE_SIZE);
612 break;
613 default:
614 return -EOPNOTSUPP;
615 }
616
617 /* process PER, also if the instrution is processed in user space */
618 if (vcpu->arch.sie_block->icptstatus & 0x02 &&
619 (!rc || rc == -EOPNOTSUPP))
620 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu);
621 return per_rc ? per_rc : rc;
622}
1/*
2 * in-kernel handling for sie intercepts
3 *
4 * Copyright IBM Corp. 2008, 2014
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 * Christian Borntraeger <borntraeger@de.ibm.com>
12 */
13
14#include <linux/kvm_host.h>
15#include <linux/errno.h>
16#include <linux/pagemap.h>
17
18#include <asm/kvm_host.h>
19#include <asm/asm-offsets.h>
20#include <asm/irq.h>
21
22#include "kvm-s390.h"
23#include "gaccess.h"
24#include "trace.h"
25#include "trace-s390.h"
26
27
28static const intercept_handler_t instruction_handlers[256] = {
29 [0x01] = kvm_s390_handle_01,
30 [0x82] = kvm_s390_handle_lpsw,
31 [0x83] = kvm_s390_handle_diag,
32 [0xae] = kvm_s390_handle_sigp,
33 [0xb2] = kvm_s390_handle_b2,
34 [0xb6] = kvm_s390_handle_stctl,
35 [0xb7] = kvm_s390_handle_lctl,
36 [0xb9] = kvm_s390_handle_b9,
37 [0xe5] = kvm_s390_handle_e5,
38 [0xeb] = kvm_s390_handle_eb,
39};
40
41u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
42{
43 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
44 u8 ilen = 0;
45
46 switch (vcpu->arch.sie_block->icptcode) {
47 case ICPT_INST:
48 case ICPT_INSTPROGI:
49 case ICPT_OPEREXC:
50 case ICPT_PARTEXEC:
51 case ICPT_IOINST:
52 /* instruction only stored for these icptcodes */
53 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8);
54 /* Use the length of the EXECUTE instruction if necessary */
55 if (sie_block->icptstatus & 1) {
56 ilen = (sie_block->icptstatus >> 4) & 0x6;
57 if (!ilen)
58 ilen = 4;
59 }
60 break;
61 case ICPT_PROGI:
62 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */
63 ilen = vcpu->arch.sie_block->pgmilc & 0x6;
64 break;
65 }
66 return ilen;
67}
68
69static int handle_noop(struct kvm_vcpu *vcpu)
70{
71 switch (vcpu->arch.sie_block->icptcode) {
72 case 0x10:
73 vcpu->stat.exit_external_request++;
74 break;
75 default:
76 break; /* nothing */
77 }
78 return 0;
79}
80
81static int handle_stop(struct kvm_vcpu *vcpu)
82{
83 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
84 int rc = 0;
85 uint8_t flags, stop_pending;
86
87 vcpu->stat.exit_stop_request++;
88
89 /* delay the stop if any non-stop irq is pending */
90 if (kvm_s390_vcpu_has_irq(vcpu, 1))
91 return 0;
92
93 /* avoid races with the injection/SIGP STOP code */
94 spin_lock(&li->lock);
95 flags = li->irq.stop.flags;
96 stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
97 spin_unlock(&li->lock);
98
99 trace_kvm_s390_stop_request(stop_pending, flags);
100 if (!stop_pending)
101 return 0;
102
103 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
104 rc = kvm_s390_vcpu_store_status(vcpu,
105 KVM_S390_STORE_STATUS_NOADDR);
106 if (rc)
107 return rc;
108 }
109
110 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
111 kvm_s390_vcpu_stop(vcpu);
112 return -EOPNOTSUPP;
113}
114
115static int handle_validity(struct kvm_vcpu *vcpu)
116{
117 int viwhy = vcpu->arch.sie_block->ipb >> 16;
118
119 vcpu->stat.exit_validity++;
120 trace_kvm_s390_intercept_validity(vcpu, viwhy);
121 WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy);
122 return -EOPNOTSUPP;
123}
124
125static int handle_instruction(struct kvm_vcpu *vcpu)
126{
127 intercept_handler_t handler;
128
129 vcpu->stat.exit_instruction++;
130 trace_kvm_s390_intercept_instruction(vcpu,
131 vcpu->arch.sie_block->ipa,
132 vcpu->arch.sie_block->ipb);
133 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
134 if (handler)
135 return handler(vcpu);
136 return -EOPNOTSUPP;
137}
138
139static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)
140{
141 struct kvm_s390_pgm_info pgm_info = {
142 .code = vcpu->arch.sie_block->iprcc,
143 /* the PSW has already been rewound */
144 .flags = KVM_S390_PGM_FLAGS_NO_REWIND,
145 };
146
147 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
148 case PGM_AFX_TRANSLATION:
149 case PGM_ASX_TRANSLATION:
150 case PGM_EX_TRANSLATION:
151 case PGM_LFX_TRANSLATION:
152 case PGM_LSTE_SEQUENCE:
153 case PGM_LSX_TRANSLATION:
154 case PGM_LX_TRANSLATION:
155 case PGM_PRIMARY_AUTHORITY:
156 case PGM_SECONDARY_AUTHORITY:
157 case PGM_SPACE_SWITCH:
158 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
159 break;
160 case PGM_ALEN_TRANSLATION:
161 case PGM_ALE_SEQUENCE:
162 case PGM_ASTE_INSTANCE:
163 case PGM_ASTE_SEQUENCE:
164 case PGM_ASTE_VALIDITY:
165 case PGM_EXTENDED_AUTHORITY:
166 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
167 break;
168 case PGM_ASCE_TYPE:
169 case PGM_PAGE_TRANSLATION:
170 case PGM_REGION_FIRST_TRANS:
171 case PGM_REGION_SECOND_TRANS:
172 case PGM_REGION_THIRD_TRANS:
173 case PGM_SEGMENT_TRANSLATION:
174 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
175 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
176 pgm_info.op_access_id = vcpu->arch.sie_block->oai;
177 break;
178 case PGM_MONITOR:
179 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn;
180 pgm_info.mon_code = vcpu->arch.sie_block->tecmc;
181 break;
182 case PGM_VECTOR_PROCESSING:
183 case PGM_DATA:
184 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc;
185 break;
186 case PGM_PROTECTION:
187 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
188 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
189 break;
190 default:
191 break;
192 }
193
194 if (vcpu->arch.sie_block->iprcc & PGM_PER) {
195 pgm_info.per_code = vcpu->arch.sie_block->perc;
196 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid;
197 pgm_info.per_address = vcpu->arch.sie_block->peraddr;
198 pgm_info.per_access_id = vcpu->arch.sie_block->peraid;
199 }
200 return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
201}
202
203/*
204 * restore ITDB to program-interruption TDB in guest lowcore
205 * and set TX abort indication if required
206*/
207static int handle_itdb(struct kvm_vcpu *vcpu)
208{
209 struct kvm_s390_itdb *itdb;
210 int rc;
211
212 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
213 return 0;
214 if (current->thread.per_flags & PER_FLAG_NO_TE)
215 return 0;
216 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba;
217 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
218 if (rc)
219 return rc;
220 memset(itdb, 0, sizeof(*itdb));
221
222 return 0;
223}
224
225#define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
226
227static int handle_prog(struct kvm_vcpu *vcpu)
228{
229 psw_t psw;
230 int rc;
231
232 vcpu->stat.exit_program_interruption++;
233
234 if (guestdbg_enabled(vcpu) && per_event(vcpu)) {
235 kvm_s390_handle_per_event(vcpu);
236 /* the interrupt might have been filtered out completely */
237 if (vcpu->arch.sie_block->iprcc == 0)
238 return 0;
239 }
240
241 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
242 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
243 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
244 if (rc)
245 return rc;
246 /* Avoid endless loops of specification exceptions */
247 if (!is_valid_psw(&psw))
248 return -EOPNOTSUPP;
249 }
250 rc = handle_itdb(vcpu);
251 if (rc)
252 return rc;
253
254 return inject_prog_on_prog_intercept(vcpu);
255}
256
257/**
258 * handle_external_interrupt - used for external interruption interceptions
259 *
260 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if
261 * the new PSW does not have external interrupts disabled. In the first case,
262 * we've got to deliver the interrupt manually, and in the second case, we
263 * drop to userspace to handle the situation there.
264 */
265static int handle_external_interrupt(struct kvm_vcpu *vcpu)
266{
267 u16 eic = vcpu->arch.sie_block->eic;
268 struct kvm_s390_irq irq;
269 psw_t newpsw;
270 int rc;
271
272 vcpu->stat.exit_external_interrupt++;
273
274 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
275 if (rc)
276 return rc;
277 /* We can not handle clock comparator or timer interrupt with bad PSW */
278 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
279 (newpsw.mask & PSW_MASK_EXT))
280 return -EOPNOTSUPP;
281
282 switch (eic) {
283 case EXT_IRQ_CLK_COMP:
284 irq.type = KVM_S390_INT_CLOCK_COMP;
285 break;
286 case EXT_IRQ_CPU_TIMER:
287 irq.type = KVM_S390_INT_CPU_TIMER;
288 break;
289 case EXT_IRQ_EXTERNAL_CALL:
290 irq.type = KVM_S390_INT_EXTERNAL_CALL;
291 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
292 rc = kvm_s390_inject_vcpu(vcpu, &irq);
293 /* ignore if another external call is already pending */
294 if (rc == -EBUSY)
295 return 0;
296 return rc;
297 default:
298 return -EOPNOTSUPP;
299 }
300
301 return kvm_s390_inject_vcpu(vcpu, &irq);
302}
303
304/**
305 * Handle MOVE PAGE partial execution interception.
306 *
307 * This interception can only happen for guests with DAT disabled and
308 * addresses that are currently not mapped in the host. Thus we try to
309 * set up the mappings for the corresponding user pages here (or throw
310 * addressing exceptions in case of illegal guest addresses).
311 */
312static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
313{
314 unsigned long srcaddr, dstaddr;
315 int reg1, reg2, rc;
316
317 kvm_s390_get_regs_rre(vcpu, ®1, ®2);
318
319 /* Make sure that the source is paged-in */
320 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2],
321 reg2, &srcaddr, GACC_FETCH);
322 if (rc)
323 return kvm_s390_inject_prog_cond(vcpu, rc);
324 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
325 if (rc != 0)
326 return rc;
327
328 /* Make sure that the destination is paged-in */
329 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1],
330 reg1, &dstaddr, GACC_STORE);
331 if (rc)
332 return kvm_s390_inject_prog_cond(vcpu, rc);
333 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
334 if (rc != 0)
335 return rc;
336
337 kvm_s390_retry_instr(vcpu);
338
339 return 0;
340}
341
342static int handle_partial_execution(struct kvm_vcpu *vcpu)
343{
344 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */
345 return handle_mvpg_pei(vcpu);
346 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */
347 return kvm_s390_handle_sigp_pei(vcpu);
348
349 return -EOPNOTSUPP;
350}
351
352int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
353{
354 if (kvm_is_ucontrol(vcpu->kvm))
355 return -EOPNOTSUPP;
356
357 switch (vcpu->arch.sie_block->icptcode) {
358 case 0x10:
359 case 0x18:
360 return handle_noop(vcpu);
361 case 0x04:
362 return handle_instruction(vcpu);
363 case 0x08:
364 return handle_prog(vcpu);
365 case 0x14:
366 return handle_external_interrupt(vcpu);
367 case 0x1c:
368 return kvm_s390_handle_wait(vcpu);
369 case 0x20:
370 return handle_validity(vcpu);
371 case 0x28:
372 return handle_stop(vcpu);
373 case 0x38:
374 return handle_partial_execution(vcpu);
375 default:
376 return -EOPNOTSUPP;
377 }
378}