1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * handling interprocessor communication
4 *
5 * Copyright IBM Corp. 2008, 2013
6 *
7 * Author(s): Carsten Otte <cotte@de.ibm.com>
8 * Christian Borntraeger <borntraeger@de.ibm.com>
9 * Christian Ehrhardt <ehrhardt@de.ibm.com>
10 */
11
12 #include <linux/kvm.h>
13 #include <linux/kvm_host.h>
14 #include <linux/slab.h>
15 #include <asm/sigp.h>
16 #include "gaccess.h"
17 #include "kvm-s390.h"
18 #include "trace.h"
19
__sigp_sense(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)20 static int __sigp_sense(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
21 u64 *reg)
22 {
23 const bool stopped = kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED);
24 int rc;
25 int ext_call_pending;
26
27 ext_call_pending = kvm_s390_ext_call_pending(dst_vcpu);
28 if (!stopped && !ext_call_pending)
29 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
30 else {
31 *reg &= 0xffffffff00000000UL;
32 if (ext_call_pending)
33 *reg |= SIGP_STATUS_EXT_CALL_PENDING;
34 if (stopped)
35 *reg |= SIGP_STATUS_STOPPED;
36 rc = SIGP_CC_STATUS_STORED;
37 }
38
39 VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", dst_vcpu->vcpu_id,
40 rc);
41 return rc;
42 }
43
__inject_sigp_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)44 static int __inject_sigp_emergency(struct kvm_vcpu *vcpu,
45 struct kvm_vcpu *dst_vcpu)
46 {
47 struct kvm_s390_irq irq = {
48 .type = KVM_S390_INT_EMERGENCY,
49 .u.emerg.code = vcpu->vcpu_id,
50 };
51 int rc = 0;
52
53 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
54 if (!rc)
55 VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x",
56 dst_vcpu->vcpu_id);
57
58 return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
59 }
60
__sigp_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)61 static int __sigp_emergency(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
62 {
63 return __inject_sigp_emergency(vcpu, dst_vcpu);
64 }
65
__sigp_conditional_emergency(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u16 asn,u64 * reg)66 static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu,
67 struct kvm_vcpu *dst_vcpu,
68 u16 asn, u64 *reg)
69 {
70 const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
71 u16 p_asn, s_asn;
72 psw_t *psw;
73 bool idle;
74
75 idle = is_vcpu_idle(vcpu);
76 psw = &dst_vcpu->arch.sie_block->gpsw;
77 p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
78 s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */
79
80 /* Inject the emergency signal? */
81 if (!is_vcpu_stopped(vcpu)
82 || (psw->mask & psw_int_mask) != psw_int_mask
83 || (idle && psw->addr != 0)
84 || (!idle && (asn == p_asn || asn == s_asn))) {
85 return __inject_sigp_emergency(vcpu, dst_vcpu);
86 } else {
87 *reg &= 0xffffffff00000000UL;
88 *reg |= SIGP_STATUS_INCORRECT_STATE;
89 return SIGP_CC_STATUS_STORED;
90 }
91 }
92
__sigp_external_call(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)93 static int __sigp_external_call(struct kvm_vcpu *vcpu,
94 struct kvm_vcpu *dst_vcpu, u64 *reg)
95 {
96 struct kvm_s390_irq irq = {
97 .type = KVM_S390_INT_EXTERNAL_CALL,
98 .u.extcall.code = vcpu->vcpu_id,
99 };
100 int rc;
101
102 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
103 if (rc == -EBUSY) {
104 *reg &= 0xffffffff00000000UL;
105 *reg |= SIGP_STATUS_EXT_CALL_PENDING;
106 return SIGP_CC_STATUS_STORED;
107 } else if (rc == 0) {
108 VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x",
109 dst_vcpu->vcpu_id);
110 }
111
112 return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
113 }
114
__sigp_stop(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)115 static int __sigp_stop(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
116 {
117 struct kvm_s390_irq irq = {
118 .type = KVM_S390_SIGP_STOP,
119 };
120 int rc;
121
122 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
123 if (rc == -EBUSY)
124 rc = SIGP_CC_BUSY;
125 else if (rc == 0)
126 VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x",
127 dst_vcpu->vcpu_id);
128
129 return rc;
130 }
131
__sigp_stop_and_store_status(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)132 static int __sigp_stop_and_store_status(struct kvm_vcpu *vcpu,
133 struct kvm_vcpu *dst_vcpu, u64 *reg)
134 {
135 struct kvm_s390_irq irq = {
136 .type = KVM_S390_SIGP_STOP,
137 .u.stop.flags = KVM_S390_STOP_FLAG_STORE_STATUS,
138 };
139 int rc;
140
141 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
142 if (rc == -EBUSY)
143 rc = SIGP_CC_BUSY;
144 else if (rc == 0)
145 VCPU_EVENT(vcpu, 4, "sent sigp stop and store status to cpu %x",
146 dst_vcpu->vcpu_id);
147
148 return rc;
149 }
150
__sigp_set_arch(struct kvm_vcpu * vcpu,u32 parameter,u64 * status_reg)151 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter,
152 u64 *status_reg)
153 {
154 unsigned int i;
155 struct kvm_vcpu *v;
156 bool all_stopped = true;
157
158 kvm_for_each_vcpu(i, v, vcpu->kvm) {
159 if (v == vcpu)
160 continue;
161 if (!is_vcpu_stopped(v))
162 all_stopped = false;
163 }
164
165 *status_reg &= 0xffffffff00000000UL;
166
167 /* Reject set arch order, with czam we're always in z/Arch mode. */
168 *status_reg |= (all_stopped ? SIGP_STATUS_INVALID_PARAMETER :
169 SIGP_STATUS_INCORRECT_STATE);
170 return SIGP_CC_STATUS_STORED;
171 }
172
__sigp_set_prefix(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 address,u64 * reg)173 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
174 u32 address, u64 *reg)
175 {
176 struct kvm_s390_irq irq = {
177 .type = KVM_S390_SIGP_SET_PREFIX,
178 .u.prefix.address = address & 0x7fffe000u,
179 };
180 int rc;
181
182 /*
183 * Make sure the new value is valid memory. We only need to check the
184 * first page, since address is 8k aligned and memory pieces are always
185 * at least 1MB aligned and have at least a size of 1MB.
186 */
187 if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) {
188 *reg &= 0xffffffff00000000UL;
189 *reg |= SIGP_STATUS_INVALID_PARAMETER;
190 return SIGP_CC_STATUS_STORED;
191 }
192
193 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
194 if (rc == -EBUSY) {
195 *reg &= 0xffffffff00000000UL;
196 *reg |= SIGP_STATUS_INCORRECT_STATE;
197 return SIGP_CC_STATUS_STORED;
198 }
199
200 return rc;
201 }
202
__sigp_store_status_at_addr(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 addr,u64 * reg)203 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu,
204 struct kvm_vcpu *dst_vcpu,
205 u32 addr, u64 *reg)
206 {
207 int rc;
208
209 if (!kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED)) {
210 *reg &= 0xffffffff00000000UL;
211 *reg |= SIGP_STATUS_INCORRECT_STATE;
212 return SIGP_CC_STATUS_STORED;
213 }
214
215 addr &= 0x7ffffe00;
216 rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
217 if (rc == -EFAULT) {
218 *reg &= 0xffffffff00000000UL;
219 *reg |= SIGP_STATUS_INVALID_PARAMETER;
220 rc = SIGP_CC_STATUS_STORED;
221 }
222 return rc;
223 }
224
__sigp_sense_running(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)225 static int __sigp_sense_running(struct kvm_vcpu *vcpu,
226 struct kvm_vcpu *dst_vcpu, u64 *reg)
227 {
228 int rc;
229
230 if (!test_kvm_facility(vcpu->kvm, 9)) {
231 *reg &= 0xffffffff00000000UL;
232 *reg |= SIGP_STATUS_INVALID_ORDER;
233 return SIGP_CC_STATUS_STORED;
234 }
235
236 if (kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_RUNNING)) {
237 /* running */
238 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
239 } else {
240 /* not running */
241 *reg &= 0xffffffff00000000UL;
242 *reg |= SIGP_STATUS_NOT_RUNNING;
243 rc = SIGP_CC_STATUS_STORED;
244 }
245
246 VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x",
247 dst_vcpu->vcpu_id, rc);
248
249 return rc;
250 }
251
__prepare_sigp_re_start(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)252 static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
253 struct kvm_vcpu *dst_vcpu, u8 order_code)
254 {
255 struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
256 /* handle (RE)START in user space */
257 int rc = -EOPNOTSUPP;
258
259 /* make sure we don't race with STOP irq injection */
260 spin_lock(&li->lock);
261 if (kvm_s390_is_stop_irq_pending(dst_vcpu))
262 rc = SIGP_CC_BUSY;
263 spin_unlock(&li->lock);
264
265 return rc;
266 }
267
__prepare_sigp_cpu_reset(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)268 static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
269 struct kvm_vcpu *dst_vcpu, u8 order_code)
270 {
271 /* handle (INITIAL) CPU RESET in user space */
272 return -EOPNOTSUPP;
273 }
274
__prepare_sigp_unknown(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)275 static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu,
276 struct kvm_vcpu *dst_vcpu)
277 {
278 /* handle unknown orders in user space */
279 return -EOPNOTSUPP;
280 }
281
handle_sigp_dst(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr,u32 parameter,u64 * status_reg)282 static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
283 u16 cpu_addr, u32 parameter, u64 *status_reg)
284 {
285 int rc;
286 struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
287
288 if (!dst_vcpu)
289 return SIGP_CC_NOT_OPERATIONAL;
290
291 switch (order_code) {
292 case SIGP_SENSE:
293 vcpu->stat.instruction_sigp_sense++;
294 rc = __sigp_sense(vcpu, dst_vcpu, status_reg);
295 break;
296 case SIGP_EXTERNAL_CALL:
297 vcpu->stat.instruction_sigp_external_call++;
298 rc = __sigp_external_call(vcpu, dst_vcpu, status_reg);
299 break;
300 case SIGP_EMERGENCY_SIGNAL:
301 vcpu->stat.instruction_sigp_emergency++;
302 rc = __sigp_emergency(vcpu, dst_vcpu);
303 break;
304 case SIGP_STOP:
305 vcpu->stat.instruction_sigp_stop++;
306 rc = __sigp_stop(vcpu, dst_vcpu);
307 break;
308 case SIGP_STOP_AND_STORE_STATUS:
309 vcpu->stat.instruction_sigp_stop_store_status++;
310 rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg);
311 break;
312 case SIGP_STORE_STATUS_AT_ADDRESS:
313 vcpu->stat.instruction_sigp_store_status++;
314 rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter,
315 status_reg);
316 break;
317 case SIGP_SET_PREFIX:
318 vcpu->stat.instruction_sigp_prefix++;
319 rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg);
320 break;
321 case SIGP_COND_EMERGENCY_SIGNAL:
322 vcpu->stat.instruction_sigp_cond_emergency++;
323 rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter,
324 status_reg);
325 break;
326 case SIGP_SENSE_RUNNING:
327 vcpu->stat.instruction_sigp_sense_running++;
328 rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg);
329 break;
330 case SIGP_START:
331 vcpu->stat.instruction_sigp_start++;
332 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
333 break;
334 case SIGP_RESTART:
335 vcpu->stat.instruction_sigp_restart++;
336 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
337 break;
338 case SIGP_INITIAL_CPU_RESET:
339 vcpu->stat.instruction_sigp_init_cpu_reset++;
340 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
341 break;
342 case SIGP_CPU_RESET:
343 vcpu->stat.instruction_sigp_cpu_reset++;
344 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
345 break;
346 default:
347 vcpu->stat.instruction_sigp_unknown++;
348 rc = __prepare_sigp_unknown(vcpu, dst_vcpu);
349 }
350
351 if (rc == -EOPNOTSUPP)
352 VCPU_EVENT(vcpu, 4,
353 "sigp order %u -> cpu %x: handled in user space",
354 order_code, dst_vcpu->vcpu_id);
355
356 return rc;
357 }
358
handle_sigp_order_in_user_space(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr)359 static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code,
360 u16 cpu_addr)
361 {
362 if (!vcpu->kvm->arch.user_sigp)
363 return 0;
364
365 switch (order_code) {
366 case SIGP_SENSE:
367 case SIGP_EXTERNAL_CALL:
368 case SIGP_EMERGENCY_SIGNAL:
369 case SIGP_COND_EMERGENCY_SIGNAL:
370 case SIGP_SENSE_RUNNING:
371 return 0;
372 /* update counters as we're directly dropping to user space */
373 case SIGP_STOP:
374 vcpu->stat.instruction_sigp_stop++;
375 break;
376 case SIGP_STOP_AND_STORE_STATUS:
377 vcpu->stat.instruction_sigp_stop_store_status++;
378 break;
379 case SIGP_STORE_STATUS_AT_ADDRESS:
380 vcpu->stat.instruction_sigp_store_status++;
381 break;
382 case SIGP_STORE_ADDITIONAL_STATUS:
383 vcpu->stat.instruction_sigp_store_adtl_status++;
384 break;
385 case SIGP_SET_PREFIX:
386 vcpu->stat.instruction_sigp_prefix++;
387 break;
388 case SIGP_START:
389 vcpu->stat.instruction_sigp_start++;
390 break;
391 case SIGP_RESTART:
392 vcpu->stat.instruction_sigp_restart++;
393 break;
394 case SIGP_INITIAL_CPU_RESET:
395 vcpu->stat.instruction_sigp_init_cpu_reset++;
396 break;
397 case SIGP_CPU_RESET:
398 vcpu->stat.instruction_sigp_cpu_reset++;
399 break;
400 default:
401 vcpu->stat.instruction_sigp_unknown++;
402 }
403 VCPU_EVENT(vcpu, 3, "SIGP: order %u for CPU %d handled in userspace",
404 order_code, cpu_addr);
405
406 return 1;
407 }
408
kvm_s390_handle_sigp(struct kvm_vcpu * vcpu)409 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
410 {
411 int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
412 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
413 u32 parameter;
414 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
415 u8 order_code;
416 int rc;
417
418 /* sigp in userspace can exit */
419 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
420 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
421
422 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
423 if (handle_sigp_order_in_user_space(vcpu, order_code, cpu_addr))
424 return -EOPNOTSUPP;
425
426 if (r1 % 2)
427 parameter = vcpu->run->s.regs.gprs[r1];
428 else
429 parameter = vcpu->run->s.regs.gprs[r1 + 1];
430
431 trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
432 switch (order_code) {
433 case SIGP_SET_ARCHITECTURE:
434 vcpu->stat.instruction_sigp_arch++;
435 rc = __sigp_set_arch(vcpu, parameter,
436 &vcpu->run->s.regs.gprs[r1]);
437 break;
438 default:
439 rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
440 parameter,
441 &vcpu->run->s.regs.gprs[r1]);
442 }
443
444 if (rc < 0)
445 return rc;
446
447 kvm_s390_set_psw_cc(vcpu, rc);
448 return 0;
449 }
450
451 /*
452 * Handle SIGP partial execution interception.
453 *
454 * This interception will occur at the source cpu when a source cpu sends an
455 * external call to a target cpu and the target cpu has the WAIT bit set in
456 * its cpuflags. Interception will occurr after the interrupt indicator bits at
457 * the target cpu have been set. All error cases will lead to instruction
458 * interception, therefore nothing is to be checked or prepared.
459 */
kvm_s390_handle_sigp_pei(struct kvm_vcpu * vcpu)460 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
461 {
462 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
463 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
464 struct kvm_vcpu *dest_vcpu;
465 u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
466
467 trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
468
469 if (order_code == SIGP_EXTERNAL_CALL) {
470 dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
471 BUG_ON(dest_vcpu == NULL);
472
473 kvm_s390_vcpu_wakeup(dest_vcpu);
474 kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
475 return 0;
476 }
477
478 return -EOPNOTSUPP;
479 }
480