1 /*
2 * handling interprocessor communication
3 *
4 * Copyright IBM Corp. 2008, 2013
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 * Christian Ehrhardt <ehrhardt@de.ibm.com>
13 */
14
15 #include <linux/kvm.h>
16 #include <linux/kvm_host.h>
17 #include <linux/slab.h>
18 #include <asm/sigp.h>
19 #include "gaccess.h"
20 #include "kvm-s390.h"
21 #include "trace.h"
22
__sigp_sense(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)23 static int __sigp_sense(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
24 u64 *reg)
25 {
26 struct kvm_s390_local_interrupt *li;
27 int cpuflags;
28 int rc;
29 int ext_call_pending;
30
31 li = &dst_vcpu->arch.local_int;
32
33 cpuflags = atomic_read(li->cpuflags);
34 ext_call_pending = kvm_s390_ext_call_pending(dst_vcpu);
35 if (!(cpuflags & CPUSTAT_STOPPED) && !ext_call_pending)
36 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
37 else {
38 *reg &= 0xffffffff00000000UL;
39 if (ext_call_pending)
40 *reg |= SIGP_STATUS_EXT_CALL_PENDING;
41 if (cpuflags & CPUSTAT_STOPPED)
42 *reg |= SIGP_STATUS_STOPPED;
43 rc = SIGP_CC_STATUS_STORED;
44 }
45
46 VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", dst_vcpu->vcpu_id,
47 rc);
48 return rc;
49 }
50
__inject_sigp_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)51 static int __inject_sigp_emergency(struct kvm_vcpu *vcpu,
52 struct kvm_vcpu *dst_vcpu)
53 {
54 struct kvm_s390_irq irq = {
55 .type = KVM_S390_INT_EMERGENCY,
56 .u.emerg.code = vcpu->vcpu_id,
57 };
58 int rc = 0;
59
60 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
61 if (!rc)
62 VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x",
63 dst_vcpu->vcpu_id);
64
65 return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
66 }
67
__sigp_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)68 static int __sigp_emergency(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
69 {
70 return __inject_sigp_emergency(vcpu, dst_vcpu);
71 }
72
__sigp_conditional_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u16 asn,u64 * reg)73 static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu,
74 struct kvm_vcpu *dst_vcpu,
75 u16 asn, u64 *reg)
76 {
77 const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
78 u16 p_asn, s_asn;
79 psw_t *psw;
80 u32 flags;
81
82 flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
83 psw = &dst_vcpu->arch.sie_block->gpsw;
84 p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
85 s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */
86
87 /* Inject the emergency signal? */
88 if (!(flags & CPUSTAT_STOPPED)
89 || (psw->mask & psw_int_mask) != psw_int_mask
90 || ((flags & CPUSTAT_WAIT) && psw->addr != 0)
91 || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) {
92 return __inject_sigp_emergency(vcpu, dst_vcpu);
93 } else {
94 *reg &= 0xffffffff00000000UL;
95 *reg |= SIGP_STATUS_INCORRECT_STATE;
96 return SIGP_CC_STATUS_STORED;
97 }
98 }
99
__sigp_external_call(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)100 static int __sigp_external_call(struct kvm_vcpu *vcpu,
101 struct kvm_vcpu *dst_vcpu, u64 *reg)
102 {
103 struct kvm_s390_irq irq = {
104 .type = KVM_S390_INT_EXTERNAL_CALL,
105 .u.extcall.code = vcpu->vcpu_id,
106 };
107 int rc;
108
109 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
110 if (rc == -EBUSY) {
111 *reg &= 0xffffffff00000000UL;
112 *reg |= SIGP_STATUS_EXT_CALL_PENDING;
113 return SIGP_CC_STATUS_STORED;
114 } else if (rc == 0) {
115 VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x",
116 dst_vcpu->vcpu_id);
117 }
118
119 return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
120 }
121
__sigp_stop(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)122 static int __sigp_stop(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
123 {
124 struct kvm_s390_irq irq = {
125 .type = KVM_S390_SIGP_STOP,
126 };
127 int rc;
128
129 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
130 if (rc == -EBUSY)
131 rc = SIGP_CC_BUSY;
132 else if (rc == 0)
133 VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x",
134 dst_vcpu->vcpu_id);
135
136 return rc;
137 }
138
__sigp_stop_and_store_status(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)139 static int __sigp_stop_and_store_status(struct kvm_vcpu *vcpu,
140 struct kvm_vcpu *dst_vcpu, u64 *reg)
141 {
142 struct kvm_s390_irq irq = {
143 .type = KVM_S390_SIGP_STOP,
144 .u.stop.flags = KVM_S390_STOP_FLAG_STORE_STATUS,
145 };
146 int rc;
147
148 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
149 if (rc == -EBUSY)
150 rc = SIGP_CC_BUSY;
151 else if (rc == 0)
152 VCPU_EVENT(vcpu, 4, "sent sigp stop and store status to cpu %x",
153 dst_vcpu->vcpu_id);
154
155 return rc;
156 }
157
__sigp_set_arch(struct kvm_vcpu * vcpu,u32 parameter)158 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
159 {
160 int rc;
161 unsigned int i;
162 struct kvm_vcpu *v;
163
164 switch (parameter & 0xff) {
165 case 0:
166 rc = SIGP_CC_NOT_OPERATIONAL;
167 break;
168 case 1:
169 case 2:
170 kvm_for_each_vcpu(i, v, vcpu->kvm) {
171 v->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
172 kvm_clear_async_pf_completion_queue(v);
173 }
174
175 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
176 break;
177 default:
178 rc = -EOPNOTSUPP;
179 }
180 return rc;
181 }
182
__sigp_set_prefix(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 address,u64 * reg)183 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
184 u32 address, u64 *reg)
185 {
186 struct kvm_s390_irq irq = {
187 .type = KVM_S390_SIGP_SET_PREFIX,
188 .u.prefix.address = address & 0x7fffe000u,
189 };
190 int rc;
191
192 /*
193 * Make sure the new value is valid memory. We only need to check the
194 * first page, since address is 8k aligned and memory pieces are always
195 * at least 1MB aligned and have at least a size of 1MB.
196 */
197 if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) {
198 *reg &= 0xffffffff00000000UL;
199 *reg |= SIGP_STATUS_INVALID_PARAMETER;
200 return SIGP_CC_STATUS_STORED;
201 }
202
203 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
204 if (rc == -EBUSY) {
205 *reg &= 0xffffffff00000000UL;
206 *reg |= SIGP_STATUS_INCORRECT_STATE;
207 return SIGP_CC_STATUS_STORED;
208 }
209
210 return rc;
211 }
212
__sigp_store_status_at_addr(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 addr,u64 * reg)213 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu,
214 struct kvm_vcpu *dst_vcpu,
215 u32 addr, u64 *reg)
216 {
217 int flags;
218 int rc;
219
220 flags = atomic_read(dst_vcpu->arch.local_int.cpuflags);
221 if (!(flags & CPUSTAT_STOPPED)) {
222 *reg &= 0xffffffff00000000UL;
223 *reg |= SIGP_STATUS_INCORRECT_STATE;
224 return SIGP_CC_STATUS_STORED;
225 }
226
227 addr &= 0x7ffffe00;
228 rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
229 if (rc == -EFAULT) {
230 *reg &= 0xffffffff00000000UL;
231 *reg |= SIGP_STATUS_INVALID_PARAMETER;
232 rc = SIGP_CC_STATUS_STORED;
233 }
234 return rc;
235 }
236
__sigp_sense_running(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)237 static int __sigp_sense_running(struct kvm_vcpu *vcpu,
238 struct kvm_vcpu *dst_vcpu, u64 *reg)
239 {
240 struct kvm_s390_local_interrupt *li;
241 int rc;
242
243 li = &dst_vcpu->arch.local_int;
244 if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
245 /* running */
246 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
247 } else {
248 /* not running */
249 *reg &= 0xffffffff00000000UL;
250 *reg |= SIGP_STATUS_NOT_RUNNING;
251 rc = SIGP_CC_STATUS_STORED;
252 }
253
254 VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x",
255 dst_vcpu->vcpu_id, rc);
256
257 return rc;
258 }
259
__prepare_sigp_re_start(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)260 static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
261 struct kvm_vcpu *dst_vcpu, u8 order_code)
262 {
263 struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
264 /* handle (RE)START in user space */
265 int rc = -EOPNOTSUPP;
266
267 /* make sure we don't race with STOP irq injection */
268 spin_lock(&li->lock);
269 if (kvm_s390_is_stop_irq_pending(dst_vcpu))
270 rc = SIGP_CC_BUSY;
271 spin_unlock(&li->lock);
272
273 return rc;
274 }
275
__prepare_sigp_cpu_reset(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)276 static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
277 struct kvm_vcpu *dst_vcpu, u8 order_code)
278 {
279 /* handle (INITIAL) CPU RESET in user space */
280 return -EOPNOTSUPP;
281 }
282
__prepare_sigp_unknown(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)283 static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu,
284 struct kvm_vcpu *dst_vcpu)
285 {
286 /* handle unknown orders in user space */
287 return -EOPNOTSUPP;
288 }
289
handle_sigp_dst(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr,u32 parameter,u64 * status_reg)290 static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
291 u16 cpu_addr, u32 parameter, u64 *status_reg)
292 {
293 int rc;
294 struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
295
296 if (!dst_vcpu)
297 return SIGP_CC_NOT_OPERATIONAL;
298
299 switch (order_code) {
300 case SIGP_SENSE:
301 vcpu->stat.instruction_sigp_sense++;
302 rc = __sigp_sense(vcpu, dst_vcpu, status_reg);
303 break;
304 case SIGP_EXTERNAL_CALL:
305 vcpu->stat.instruction_sigp_external_call++;
306 rc = __sigp_external_call(vcpu, dst_vcpu, status_reg);
307 break;
308 case SIGP_EMERGENCY_SIGNAL:
309 vcpu->stat.instruction_sigp_emergency++;
310 rc = __sigp_emergency(vcpu, dst_vcpu);
311 break;
312 case SIGP_STOP:
313 vcpu->stat.instruction_sigp_stop++;
314 rc = __sigp_stop(vcpu, dst_vcpu);
315 break;
316 case SIGP_STOP_AND_STORE_STATUS:
317 vcpu->stat.instruction_sigp_stop_store_status++;
318 rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg);
319 break;
320 case SIGP_STORE_STATUS_AT_ADDRESS:
321 vcpu->stat.instruction_sigp_store_status++;
322 rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter,
323 status_reg);
324 break;
325 case SIGP_SET_PREFIX:
326 vcpu->stat.instruction_sigp_prefix++;
327 rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg);
328 break;
329 case SIGP_COND_EMERGENCY_SIGNAL:
330 vcpu->stat.instruction_sigp_cond_emergency++;
331 rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter,
332 status_reg);
333 break;
334 case SIGP_SENSE_RUNNING:
335 vcpu->stat.instruction_sigp_sense_running++;
336 rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg);
337 break;
338 case SIGP_START:
339 vcpu->stat.instruction_sigp_start++;
340 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
341 break;
342 case SIGP_RESTART:
343 vcpu->stat.instruction_sigp_restart++;
344 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
345 break;
346 case SIGP_INITIAL_CPU_RESET:
347 vcpu->stat.instruction_sigp_init_cpu_reset++;
348 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
349 break;
350 case SIGP_CPU_RESET:
351 vcpu->stat.instruction_sigp_cpu_reset++;
352 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
353 break;
354 default:
355 vcpu->stat.instruction_sigp_unknown++;
356 rc = __prepare_sigp_unknown(vcpu, dst_vcpu);
357 }
358
359 if (rc == -EOPNOTSUPP)
360 VCPU_EVENT(vcpu, 4,
361 "sigp order %u -> cpu %x: handled in user space",
362 order_code, dst_vcpu->vcpu_id);
363
364 return rc;
365 }
366
handle_sigp_order_in_user_space(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr)367 static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code,
368 u16 cpu_addr)
369 {
370 if (!vcpu->kvm->arch.user_sigp)
371 return 0;
372
373 switch (order_code) {
374 case SIGP_SENSE:
375 case SIGP_EXTERNAL_CALL:
376 case SIGP_EMERGENCY_SIGNAL:
377 case SIGP_COND_EMERGENCY_SIGNAL:
378 case SIGP_SENSE_RUNNING:
379 return 0;
380 /* update counters as we're directly dropping to user space */
381 case SIGP_STOP:
382 vcpu->stat.instruction_sigp_stop++;
383 break;
384 case SIGP_STOP_AND_STORE_STATUS:
385 vcpu->stat.instruction_sigp_stop_store_status++;
386 break;
387 case SIGP_STORE_STATUS_AT_ADDRESS:
388 vcpu->stat.instruction_sigp_store_status++;
389 break;
390 case SIGP_STORE_ADDITIONAL_STATUS:
391 vcpu->stat.instruction_sigp_store_adtl_status++;
392 break;
393 case SIGP_SET_PREFIX:
394 vcpu->stat.instruction_sigp_prefix++;
395 break;
396 case SIGP_START:
397 vcpu->stat.instruction_sigp_start++;
398 break;
399 case SIGP_RESTART:
400 vcpu->stat.instruction_sigp_restart++;
401 break;
402 case SIGP_INITIAL_CPU_RESET:
403 vcpu->stat.instruction_sigp_init_cpu_reset++;
404 break;
405 case SIGP_CPU_RESET:
406 vcpu->stat.instruction_sigp_cpu_reset++;
407 break;
408 default:
409 vcpu->stat.instruction_sigp_unknown++;
410 }
411 VCPU_EVENT(vcpu, 3, "SIGP: order %u for CPU %d handled in userspace",
412 order_code, cpu_addr);
413
414 return 1;
415 }
416
kvm_s390_handle_sigp(struct kvm_vcpu * vcpu)417 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
418 {
419 int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
420 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
421 u32 parameter;
422 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
423 u8 order_code;
424 int rc;
425
426 /* sigp in userspace can exit */
427 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
428 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
429
430 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
431 if (handle_sigp_order_in_user_space(vcpu, order_code, cpu_addr))
432 return -EOPNOTSUPP;
433
434 if (r1 % 2)
435 parameter = vcpu->run->s.regs.gprs[r1];
436 else
437 parameter = vcpu->run->s.regs.gprs[r1 + 1];
438
439 trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
440 switch (order_code) {
441 case SIGP_SET_ARCHITECTURE:
442 vcpu->stat.instruction_sigp_arch++;
443 rc = __sigp_set_arch(vcpu, parameter);
444 break;
445 default:
446 rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
447 parameter,
448 &vcpu->run->s.regs.gprs[r1]);
449 }
450
451 if (rc < 0)
452 return rc;
453
454 kvm_s390_set_psw_cc(vcpu, rc);
455 return 0;
456 }
457
458 /*
459 * Handle SIGP partial execution interception.
460 *
461 * This interception will occur at the source cpu when a source cpu sends an
462 * external call to a target cpu and the target cpu has the WAIT bit set in
463 * its cpuflags. Interception will occurr after the interrupt indicator bits at
464 * the target cpu have been set. All error cases will lead to instruction
465 * interception, therefore nothing is to be checked or prepared.
466 */
kvm_s390_handle_sigp_pei(struct kvm_vcpu * vcpu)467 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
468 {
469 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
470 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
471 struct kvm_vcpu *dest_vcpu;
472 u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
473
474 trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
475
476 if (order_code == SIGP_EXTERNAL_CALL) {
477 dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
478 BUG_ON(dest_vcpu == NULL);
479
480 kvm_s390_vcpu_wakeup(dest_vcpu);
481 kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
482 return 0;
483 }
484
485 return -EOPNOTSUPP;
486 }
487