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 *status_reg &= 0xffffffff00000000UL;
155
156 /* Reject set arch order, with czam we're always in z/Arch mode. */
157 *status_reg |= SIGP_STATUS_INVALID_PARAMETER;
158 return SIGP_CC_STATUS_STORED;
159 }
160
__sigp_set_prefix(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 address,u64 * reg)161 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
162 u32 address, u64 *reg)
163 {
164 struct kvm_s390_irq irq = {
165 .type = KVM_S390_SIGP_SET_PREFIX,
166 .u.prefix.address = address & 0x7fffe000u,
167 };
168 int rc;
169
170 /*
171 * Make sure the new value is valid memory. We only need to check the
172 * first page, since address is 8k aligned and memory pieces are always
173 * at least 1MB aligned and have at least a size of 1MB.
174 */
175 if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) {
176 *reg &= 0xffffffff00000000UL;
177 *reg |= SIGP_STATUS_INVALID_PARAMETER;
178 return SIGP_CC_STATUS_STORED;
179 }
180
181 rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
182 if (rc == -EBUSY) {
183 *reg &= 0xffffffff00000000UL;
184 *reg |= SIGP_STATUS_INCORRECT_STATE;
185 return SIGP_CC_STATUS_STORED;
186 }
187
188 return rc;
189 }
190
__sigp_store_status_at_addr(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 addr,u64 * reg)191 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu,
192 struct kvm_vcpu *dst_vcpu,
193 u32 addr, u64 *reg)
194 {
195 int rc;
196
197 if (!kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED)) {
198 *reg &= 0xffffffff00000000UL;
199 *reg |= SIGP_STATUS_INCORRECT_STATE;
200 return SIGP_CC_STATUS_STORED;
201 }
202
203 addr &= 0x7ffffe00;
204 rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
205 if (rc == -EFAULT) {
206 *reg &= 0xffffffff00000000UL;
207 *reg |= SIGP_STATUS_INVALID_PARAMETER;
208 rc = SIGP_CC_STATUS_STORED;
209 }
210 return rc;
211 }
212
__sigp_sense_running(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)213 static int __sigp_sense_running(struct kvm_vcpu *vcpu,
214 struct kvm_vcpu *dst_vcpu, u64 *reg)
215 {
216 int rc;
217
218 if (!test_kvm_facility(vcpu->kvm, 9)) {
219 *reg &= 0xffffffff00000000UL;
220 *reg |= SIGP_STATUS_INVALID_ORDER;
221 return SIGP_CC_STATUS_STORED;
222 }
223
224 if (kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_RUNNING)) {
225 /* running */
226 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
227 } else {
228 /* not running */
229 *reg &= 0xffffffff00000000UL;
230 *reg |= SIGP_STATUS_NOT_RUNNING;
231 rc = SIGP_CC_STATUS_STORED;
232 }
233
234 VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x",
235 dst_vcpu->vcpu_id, rc);
236
237 return rc;
238 }
239
__prepare_sigp_re_start(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)240 static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
241 struct kvm_vcpu *dst_vcpu, u8 order_code)
242 {
243 struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
244 /* handle (RE)START in user space */
245 int rc = -EOPNOTSUPP;
246
247 /* make sure we don't race with STOP irq injection */
248 spin_lock(&li->lock);
249 if (kvm_s390_is_stop_irq_pending(dst_vcpu))
250 rc = SIGP_CC_BUSY;
251 spin_unlock(&li->lock);
252
253 return rc;
254 }
255
__prepare_sigp_cpu_reset(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)256 static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
257 struct kvm_vcpu *dst_vcpu, u8 order_code)
258 {
259 /* handle (INITIAL) CPU RESET in user space */
260 return -EOPNOTSUPP;
261 }
262
__prepare_sigp_unknown(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)263 static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu,
264 struct kvm_vcpu *dst_vcpu)
265 {
266 /* handle unknown orders in user space */
267 return -EOPNOTSUPP;
268 }
269
handle_sigp_dst(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr,u32 parameter,u64 * status_reg)270 static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
271 u16 cpu_addr, u32 parameter, u64 *status_reg)
272 {
273 int rc;
274 struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
275
276 if (!dst_vcpu)
277 return SIGP_CC_NOT_OPERATIONAL;
278
279 switch (order_code) {
280 case SIGP_SENSE:
281 vcpu->stat.instruction_sigp_sense++;
282 rc = __sigp_sense(vcpu, dst_vcpu, status_reg);
283 break;
284 case SIGP_EXTERNAL_CALL:
285 vcpu->stat.instruction_sigp_external_call++;
286 rc = __sigp_external_call(vcpu, dst_vcpu, status_reg);
287 break;
288 case SIGP_EMERGENCY_SIGNAL:
289 vcpu->stat.instruction_sigp_emergency++;
290 rc = __sigp_emergency(vcpu, dst_vcpu);
291 break;
292 case SIGP_STOP:
293 vcpu->stat.instruction_sigp_stop++;
294 rc = __sigp_stop(vcpu, dst_vcpu);
295 break;
296 case SIGP_STOP_AND_STORE_STATUS:
297 vcpu->stat.instruction_sigp_stop_store_status++;
298 rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg);
299 break;
300 case SIGP_STORE_STATUS_AT_ADDRESS:
301 vcpu->stat.instruction_sigp_store_status++;
302 rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter,
303 status_reg);
304 break;
305 case SIGP_SET_PREFIX:
306 vcpu->stat.instruction_sigp_prefix++;
307 rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg);
308 break;
309 case SIGP_COND_EMERGENCY_SIGNAL:
310 vcpu->stat.instruction_sigp_cond_emergency++;
311 rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter,
312 status_reg);
313 break;
314 case SIGP_SENSE_RUNNING:
315 vcpu->stat.instruction_sigp_sense_running++;
316 rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg);
317 break;
318 case SIGP_START:
319 vcpu->stat.instruction_sigp_start++;
320 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
321 break;
322 case SIGP_RESTART:
323 vcpu->stat.instruction_sigp_restart++;
324 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
325 break;
326 case SIGP_INITIAL_CPU_RESET:
327 vcpu->stat.instruction_sigp_init_cpu_reset++;
328 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
329 break;
330 case SIGP_CPU_RESET:
331 vcpu->stat.instruction_sigp_cpu_reset++;
332 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
333 break;
334 default:
335 vcpu->stat.instruction_sigp_unknown++;
336 rc = __prepare_sigp_unknown(vcpu, dst_vcpu);
337 }
338
339 if (rc == -EOPNOTSUPP)
340 VCPU_EVENT(vcpu, 4,
341 "sigp order %u -> cpu %x: handled in user space",
342 order_code, dst_vcpu->vcpu_id);
343
344 return rc;
345 }
346
handle_sigp_order_in_user_space(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr)347 static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code,
348 u16 cpu_addr)
349 {
350 if (!vcpu->kvm->arch.user_sigp)
351 return 0;
352
353 switch (order_code) {
354 case SIGP_SENSE:
355 case SIGP_EXTERNAL_CALL:
356 case SIGP_EMERGENCY_SIGNAL:
357 case SIGP_COND_EMERGENCY_SIGNAL:
358 case SIGP_SENSE_RUNNING:
359 return 0;
360 /* update counters as we're directly dropping to user space */
361 case SIGP_STOP:
362 vcpu->stat.instruction_sigp_stop++;
363 break;
364 case SIGP_STOP_AND_STORE_STATUS:
365 vcpu->stat.instruction_sigp_stop_store_status++;
366 break;
367 case SIGP_STORE_STATUS_AT_ADDRESS:
368 vcpu->stat.instruction_sigp_store_status++;
369 break;
370 case SIGP_STORE_ADDITIONAL_STATUS:
371 vcpu->stat.instruction_sigp_store_adtl_status++;
372 break;
373 case SIGP_SET_PREFIX:
374 vcpu->stat.instruction_sigp_prefix++;
375 break;
376 case SIGP_START:
377 vcpu->stat.instruction_sigp_start++;
378 break;
379 case SIGP_RESTART:
380 vcpu->stat.instruction_sigp_restart++;
381 break;
382 case SIGP_INITIAL_CPU_RESET:
383 vcpu->stat.instruction_sigp_init_cpu_reset++;
384 break;
385 case SIGP_CPU_RESET:
386 vcpu->stat.instruction_sigp_cpu_reset++;
387 break;
388 default:
389 vcpu->stat.instruction_sigp_unknown++;
390 }
391 VCPU_EVENT(vcpu, 3, "SIGP: order %u for CPU %d handled in userspace",
392 order_code, cpu_addr);
393
394 return 1;
395 }
396
kvm_s390_handle_sigp(struct kvm_vcpu * vcpu)397 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
398 {
399 int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
400 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
401 u32 parameter;
402 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
403 u8 order_code;
404 int rc;
405
406 /* sigp in userspace can exit */
407 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
408 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
409
410 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
411 if (handle_sigp_order_in_user_space(vcpu, order_code, cpu_addr))
412 return -EOPNOTSUPP;
413
414 if (r1 % 2)
415 parameter = vcpu->run->s.regs.gprs[r1];
416 else
417 parameter = vcpu->run->s.regs.gprs[r1 + 1];
418
419 trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
420 switch (order_code) {
421 case SIGP_SET_ARCHITECTURE:
422 vcpu->stat.instruction_sigp_arch++;
423 rc = __sigp_set_arch(vcpu, parameter,
424 &vcpu->run->s.regs.gprs[r1]);
425 break;
426 default:
427 rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
428 parameter,
429 &vcpu->run->s.regs.gprs[r1]);
430 }
431
432 if (rc < 0)
433 return rc;
434
435 kvm_s390_set_psw_cc(vcpu, rc);
436 return 0;
437 }
438
439 /*
440 * Handle SIGP partial execution interception.
441 *
442 * This interception will occur at the source cpu when a source cpu sends an
443 * external call to a target cpu and the target cpu has the WAIT bit set in
444 * its cpuflags. Interception will occurr after the interrupt indicator bits at
445 * the target cpu have been set. All error cases will lead to instruction
446 * interception, therefore nothing is to be checked or prepared.
447 */
kvm_s390_handle_sigp_pei(struct kvm_vcpu * vcpu)448 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
449 {
450 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
451 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
452 struct kvm_vcpu *dest_vcpu;
453 u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
454
455 trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
456
457 if (order_code == SIGP_EXTERNAL_CALL) {
458 dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
459 BUG_ON(dest_vcpu == NULL);
460
461 kvm_s390_vcpu_wakeup(dest_vcpu);
462 kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
463 return 0;
464 }
465
466 return -EOPNOTSUPP;
467 }
468