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 } else if (rc == 0) {
209 VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x",
210 dst_vcpu->vcpu_id, irq.u.prefix.address);
211 }
212
213 return rc;
214 }
215
__sigp_store_status_at_addr(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u32 addr,u64 * reg)216 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu,
217 struct kvm_vcpu *dst_vcpu,
218 u32 addr, u64 *reg)
219 {
220 int flags;
221 int rc;
222
223 flags = atomic_read(dst_vcpu->arch.local_int.cpuflags);
224 if (!(flags & CPUSTAT_STOPPED)) {
225 *reg &= 0xffffffff00000000UL;
226 *reg |= SIGP_STATUS_INCORRECT_STATE;
227 return SIGP_CC_STATUS_STORED;
228 }
229
230 addr &= 0x7ffffe00;
231 rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
232 if (rc == -EFAULT) {
233 *reg &= 0xffffffff00000000UL;
234 *reg |= SIGP_STATUS_INVALID_PARAMETER;
235 rc = SIGP_CC_STATUS_STORED;
236 }
237 return rc;
238 }
239
__sigp_sense_running(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u64 * reg)240 static int __sigp_sense_running(struct kvm_vcpu *vcpu,
241 struct kvm_vcpu *dst_vcpu, u64 *reg)
242 {
243 struct kvm_s390_local_interrupt *li;
244 int rc;
245
246 li = &dst_vcpu->arch.local_int;
247 if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
248 /* running */
249 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
250 } else {
251 /* not running */
252 *reg &= 0xffffffff00000000UL;
253 *reg |= SIGP_STATUS_NOT_RUNNING;
254 rc = SIGP_CC_STATUS_STORED;
255 }
256
257 VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x",
258 dst_vcpu->vcpu_id, rc);
259
260 return rc;
261 }
262
__prepare_sigp_re_start(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)263 static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
264 struct kvm_vcpu *dst_vcpu, u8 order_code)
265 {
266 struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
267 /* handle (RE)START in user space */
268 int rc = -EOPNOTSUPP;
269
270 /* make sure we don't race with STOP irq injection */
271 spin_lock(&li->lock);
272 if (kvm_s390_is_stop_irq_pending(dst_vcpu))
273 rc = SIGP_CC_BUSY;
274 spin_unlock(&li->lock);
275
276 return rc;
277 }
278
__prepare_sigp_cpu_reset(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu,u8 order_code)279 static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
280 struct kvm_vcpu *dst_vcpu, u8 order_code)
281 {
282 /* handle (INITIAL) CPU RESET in user space */
283 return -EOPNOTSUPP;
284 }
285
__prepare_sigp_unknown(struct kvm_vcpu * vcpu,struct kvm_vcpu * dst_vcpu)286 static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu,
287 struct kvm_vcpu *dst_vcpu)
288 {
289 /* handle unknown orders in user space */
290 return -EOPNOTSUPP;
291 }
292
handle_sigp_dst(struct kvm_vcpu * vcpu,u8 order_code,u16 cpu_addr,u32 parameter,u64 * status_reg)293 static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
294 u16 cpu_addr, u32 parameter, u64 *status_reg)
295 {
296 int rc;
297 struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
298
299 if (!dst_vcpu)
300 return SIGP_CC_NOT_OPERATIONAL;
301
302 switch (order_code) {
303 case SIGP_SENSE:
304 vcpu->stat.instruction_sigp_sense++;
305 rc = __sigp_sense(vcpu, dst_vcpu, status_reg);
306 break;
307 case SIGP_EXTERNAL_CALL:
308 vcpu->stat.instruction_sigp_external_call++;
309 rc = __sigp_external_call(vcpu, dst_vcpu, status_reg);
310 break;
311 case SIGP_EMERGENCY_SIGNAL:
312 vcpu->stat.instruction_sigp_emergency++;
313 rc = __sigp_emergency(vcpu, dst_vcpu);
314 break;
315 case SIGP_STOP:
316 vcpu->stat.instruction_sigp_stop++;
317 rc = __sigp_stop(vcpu, dst_vcpu);
318 break;
319 case SIGP_STOP_AND_STORE_STATUS:
320 vcpu->stat.instruction_sigp_stop_store_status++;
321 rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg);
322 break;
323 case SIGP_STORE_STATUS_AT_ADDRESS:
324 vcpu->stat.instruction_sigp_store_status++;
325 rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter,
326 status_reg);
327 break;
328 case SIGP_SET_PREFIX:
329 vcpu->stat.instruction_sigp_prefix++;
330 rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg);
331 break;
332 case SIGP_COND_EMERGENCY_SIGNAL:
333 vcpu->stat.instruction_sigp_cond_emergency++;
334 rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter,
335 status_reg);
336 break;
337 case SIGP_SENSE_RUNNING:
338 vcpu->stat.instruction_sigp_sense_running++;
339 rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg);
340 break;
341 case SIGP_START:
342 vcpu->stat.instruction_sigp_start++;
343 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
344 break;
345 case SIGP_RESTART:
346 vcpu->stat.instruction_sigp_restart++;
347 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
348 break;
349 case SIGP_INITIAL_CPU_RESET:
350 vcpu->stat.instruction_sigp_init_cpu_reset++;
351 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
352 break;
353 case SIGP_CPU_RESET:
354 vcpu->stat.instruction_sigp_cpu_reset++;
355 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
356 break;
357 default:
358 vcpu->stat.instruction_sigp_unknown++;
359 rc = __prepare_sigp_unknown(vcpu, dst_vcpu);
360 }
361
362 if (rc == -EOPNOTSUPP)
363 VCPU_EVENT(vcpu, 4,
364 "sigp order %u -> cpu %x: handled in user space",
365 order_code, dst_vcpu->vcpu_id);
366
367 return rc;
368 }
369
handle_sigp_order_in_user_space(struct kvm_vcpu * vcpu,u8 order_code)370 static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code)
371 {
372 if (!vcpu->kvm->arch.user_sigp)
373 return 0;
374
375 switch (order_code) {
376 case SIGP_SENSE:
377 case SIGP_EXTERNAL_CALL:
378 case SIGP_EMERGENCY_SIGNAL:
379 case SIGP_COND_EMERGENCY_SIGNAL:
380 case SIGP_SENSE_RUNNING:
381 return 0;
382 /* update counters as we're directly dropping to user space */
383 case SIGP_STOP:
384 vcpu->stat.instruction_sigp_stop++;
385 break;
386 case SIGP_STOP_AND_STORE_STATUS:
387 vcpu->stat.instruction_sigp_stop_store_status++;
388 break;
389 case SIGP_STORE_STATUS_AT_ADDRESS:
390 vcpu->stat.instruction_sigp_store_status++;
391 break;
392 case SIGP_STORE_ADDITIONAL_STATUS:
393 vcpu->stat.instruction_sigp_store_adtl_status++;
394 break;
395 case SIGP_SET_PREFIX:
396 vcpu->stat.instruction_sigp_prefix++;
397 break;
398 case SIGP_START:
399 vcpu->stat.instruction_sigp_start++;
400 break;
401 case SIGP_RESTART:
402 vcpu->stat.instruction_sigp_restart++;
403 break;
404 case SIGP_INITIAL_CPU_RESET:
405 vcpu->stat.instruction_sigp_init_cpu_reset++;
406 break;
407 case SIGP_CPU_RESET:
408 vcpu->stat.instruction_sigp_cpu_reset++;
409 break;
410 default:
411 vcpu->stat.instruction_sigp_unknown++;
412 }
413
414 VCPU_EVENT(vcpu, 4, "sigp order %u: completely handled in user space",
415 order_code);
416
417 return 1;
418 }
419
kvm_s390_handle_sigp(struct kvm_vcpu * vcpu)420 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
421 {
422 int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
423 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
424 u32 parameter;
425 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
426 u8 order_code;
427 int rc;
428
429 /* sigp in userspace can exit */
430 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
431 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
432
433 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
434 if (handle_sigp_order_in_user_space(vcpu, order_code))
435 return -EOPNOTSUPP;
436
437 if (r1 % 2)
438 parameter = vcpu->run->s.regs.gprs[r1];
439 else
440 parameter = vcpu->run->s.regs.gprs[r1 + 1];
441
442 trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
443 switch (order_code) {
444 case SIGP_SET_ARCHITECTURE:
445 vcpu->stat.instruction_sigp_arch++;
446 rc = __sigp_set_arch(vcpu, parameter);
447 break;
448 default:
449 rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
450 parameter,
451 &vcpu->run->s.regs.gprs[r1]);
452 }
453
454 if (rc < 0)
455 return rc;
456
457 kvm_s390_set_psw_cc(vcpu, rc);
458 return 0;
459 }
460
461 /*
462 * Handle SIGP partial execution interception.
463 *
464 * This interception will occur at the source cpu when a source cpu sends an
465 * external call to a target cpu and the target cpu has the WAIT bit set in
466 * its cpuflags. Interception will occurr after the interrupt indicator bits at
467 * the target cpu have been set. All error cases will lead to instruction
468 * interception, therefore nothing is to be checked or prepared.
469 */
kvm_s390_handle_sigp_pei(struct kvm_vcpu * vcpu)470 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
471 {
472 int r3 = vcpu->arch.sie_block->ipa & 0x000f;
473 u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
474 struct kvm_vcpu *dest_vcpu;
475 u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
476
477 trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
478
479 if (order_code == SIGP_EXTERNAL_CALL) {
480 dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
481 BUG_ON(dest_vcpu == NULL);
482
483 kvm_s390_vcpu_wakeup(dest_vcpu);
484 kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
485 return 0;
486 }
487
488 return -EOPNOTSUPP;
489 }
490