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
28 static 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
kvm_s390_rewind_psw(struct kvm_vcpu * vcpu,int ilc)41 void kvm_s390_rewind_psw(struct kvm_vcpu *vcpu, int ilc)
42 {
43 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
44
45 /* Use the length of the EXECUTE instruction if necessary */
46 if (sie_block->icptstatus & 1) {
47 ilc = (sie_block->icptstatus >> 4) & 0x6;
48 if (!ilc)
49 ilc = 4;
50 }
51 sie_block->gpsw.addr = __rewind_psw(sie_block->gpsw, ilc);
52 }
53
handle_noop(struct kvm_vcpu * vcpu)54 static int handle_noop(struct kvm_vcpu *vcpu)
55 {
56 switch (vcpu->arch.sie_block->icptcode) {
57 case 0x0:
58 vcpu->stat.exit_null++;
59 break;
60 case 0x10:
61 vcpu->stat.exit_external_request++;
62 break;
63 default:
64 break; /* nothing */
65 }
66 return 0;
67 }
68
handle_stop(struct kvm_vcpu * vcpu)69 static int handle_stop(struct kvm_vcpu *vcpu)
70 {
71 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
72 int rc = 0;
73 uint8_t flags, stop_pending;
74
75 vcpu->stat.exit_stop_request++;
76
77 /* delay the stop if any non-stop irq is pending */
78 if (kvm_s390_vcpu_has_irq(vcpu, 1))
79 return 0;
80
81 /* avoid races with the injection/SIGP STOP code */
82 spin_lock(&li->lock);
83 flags = li->irq.stop.flags;
84 stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
85 spin_unlock(&li->lock);
86
87 trace_kvm_s390_stop_request(stop_pending, flags);
88 if (!stop_pending)
89 return 0;
90
91 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
92 rc = kvm_s390_vcpu_store_status(vcpu,
93 KVM_S390_STORE_STATUS_NOADDR);
94 if (rc)
95 return rc;
96 }
97
98 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
99 kvm_s390_vcpu_stop(vcpu);
100 return -EOPNOTSUPP;
101 }
102
handle_validity(struct kvm_vcpu * vcpu)103 static int handle_validity(struct kvm_vcpu *vcpu)
104 {
105 int viwhy = vcpu->arch.sie_block->ipb >> 16;
106
107 vcpu->stat.exit_validity++;
108 trace_kvm_s390_intercept_validity(vcpu, viwhy);
109 WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy);
110 return -EOPNOTSUPP;
111 }
112
handle_instruction(struct kvm_vcpu * vcpu)113 static int handle_instruction(struct kvm_vcpu *vcpu)
114 {
115 intercept_handler_t handler;
116
117 vcpu->stat.exit_instruction++;
118 trace_kvm_s390_intercept_instruction(vcpu,
119 vcpu->arch.sie_block->ipa,
120 vcpu->arch.sie_block->ipb);
121 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8];
122 if (handler)
123 return handler(vcpu);
124 return -EOPNOTSUPP;
125 }
126
__extract_prog_irq(struct kvm_vcpu * vcpu,struct kvm_s390_pgm_info * pgm_info)127 static void __extract_prog_irq(struct kvm_vcpu *vcpu,
128 struct kvm_s390_pgm_info *pgm_info)
129 {
130 memset(pgm_info, 0, sizeof(struct kvm_s390_pgm_info));
131 pgm_info->code = vcpu->arch.sie_block->iprcc;
132
133 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
134 case PGM_AFX_TRANSLATION:
135 case PGM_ASX_TRANSLATION:
136 case PGM_EX_TRANSLATION:
137 case PGM_LFX_TRANSLATION:
138 case PGM_LSTE_SEQUENCE:
139 case PGM_LSX_TRANSLATION:
140 case PGM_LX_TRANSLATION:
141 case PGM_PRIMARY_AUTHORITY:
142 case PGM_SECONDARY_AUTHORITY:
143 case PGM_SPACE_SWITCH:
144 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc;
145 break;
146 case PGM_ALEN_TRANSLATION:
147 case PGM_ALE_SEQUENCE:
148 case PGM_ASTE_INSTANCE:
149 case PGM_ASTE_SEQUENCE:
150 case PGM_ASTE_VALIDITY:
151 case PGM_EXTENDED_AUTHORITY:
152 pgm_info->exc_access_id = vcpu->arch.sie_block->eai;
153 break;
154 case PGM_ASCE_TYPE:
155 case PGM_PAGE_TRANSLATION:
156 case PGM_REGION_FIRST_TRANS:
157 case PGM_REGION_SECOND_TRANS:
158 case PGM_REGION_THIRD_TRANS:
159 case PGM_SEGMENT_TRANSLATION:
160 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc;
161 pgm_info->exc_access_id = vcpu->arch.sie_block->eai;
162 pgm_info->op_access_id = vcpu->arch.sie_block->oai;
163 break;
164 case PGM_MONITOR:
165 pgm_info->mon_class_nr = vcpu->arch.sie_block->mcn;
166 pgm_info->mon_code = vcpu->arch.sie_block->tecmc;
167 break;
168 case PGM_VECTOR_PROCESSING:
169 case PGM_DATA:
170 pgm_info->data_exc_code = vcpu->arch.sie_block->dxc;
171 break;
172 case PGM_PROTECTION:
173 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc;
174 pgm_info->exc_access_id = vcpu->arch.sie_block->eai;
175 break;
176 default:
177 break;
178 }
179
180 if (vcpu->arch.sie_block->iprcc & PGM_PER) {
181 pgm_info->per_code = vcpu->arch.sie_block->perc;
182 pgm_info->per_atmid = vcpu->arch.sie_block->peratmid;
183 pgm_info->per_address = vcpu->arch.sie_block->peraddr;
184 pgm_info->per_access_id = vcpu->arch.sie_block->peraid;
185 }
186 }
187
188 /*
189 * restore ITDB to program-interruption TDB in guest lowcore
190 * and set TX abort indication if required
191 */
handle_itdb(struct kvm_vcpu * vcpu)192 static int handle_itdb(struct kvm_vcpu *vcpu)
193 {
194 struct kvm_s390_itdb *itdb;
195 int rc;
196
197 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
198 return 0;
199 if (current->thread.per_flags & PER_FLAG_NO_TE)
200 return 0;
201 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba;
202 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
203 if (rc)
204 return rc;
205 memset(itdb, 0, sizeof(*itdb));
206
207 return 0;
208 }
209
210 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
211
handle_prog(struct kvm_vcpu * vcpu)212 static int handle_prog(struct kvm_vcpu *vcpu)
213 {
214 struct kvm_s390_pgm_info pgm_info;
215 psw_t psw;
216 int rc;
217
218 vcpu->stat.exit_program_interruption++;
219
220 if (guestdbg_enabled(vcpu) && per_event(vcpu)) {
221 kvm_s390_handle_per_event(vcpu);
222 /* the interrupt might have been filtered out completely */
223 if (vcpu->arch.sie_block->iprcc == 0)
224 return 0;
225 }
226
227 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
228 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
229 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
230 if (rc)
231 return rc;
232 /* Avoid endless loops of specification exceptions */
233 if (!is_valid_psw(&psw))
234 return -EOPNOTSUPP;
235 }
236 rc = handle_itdb(vcpu);
237 if (rc)
238 return rc;
239
240 __extract_prog_irq(vcpu, &pgm_info);
241 return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
242 }
243
244 /**
245 * handle_external_interrupt - used for external interruption interceptions
246 *
247 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if
248 * the new PSW does not have external interrupts disabled. In the first case,
249 * we've got to deliver the interrupt manually, and in the second case, we
250 * drop to userspace to handle the situation there.
251 */
handle_external_interrupt(struct kvm_vcpu * vcpu)252 static int handle_external_interrupt(struct kvm_vcpu *vcpu)
253 {
254 u16 eic = vcpu->arch.sie_block->eic;
255 struct kvm_s390_irq irq;
256 psw_t newpsw;
257 int rc;
258
259 vcpu->stat.exit_external_interrupt++;
260
261 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
262 if (rc)
263 return rc;
264 /* We can not handle clock comparator or timer interrupt with bad PSW */
265 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
266 (newpsw.mask & PSW_MASK_EXT))
267 return -EOPNOTSUPP;
268
269 switch (eic) {
270 case EXT_IRQ_CLK_COMP:
271 irq.type = KVM_S390_INT_CLOCK_COMP;
272 break;
273 case EXT_IRQ_CPU_TIMER:
274 irq.type = KVM_S390_INT_CPU_TIMER;
275 break;
276 case EXT_IRQ_EXTERNAL_CALL:
277 irq.type = KVM_S390_INT_EXTERNAL_CALL;
278 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
279 rc = kvm_s390_inject_vcpu(vcpu, &irq);
280 /* ignore if another external call is already pending */
281 if (rc == -EBUSY)
282 return 0;
283 return rc;
284 default:
285 return -EOPNOTSUPP;
286 }
287
288 return kvm_s390_inject_vcpu(vcpu, &irq);
289 }
290
291 /**
292 * Handle MOVE PAGE partial execution interception.
293 *
294 * This interception can only happen for guests with DAT disabled and
295 * addresses that are currently not mapped in the host. Thus we try to
296 * set up the mappings for the corresponding user pages here (or throw
297 * addressing exceptions in case of illegal guest addresses).
298 */
handle_mvpg_pei(struct kvm_vcpu * vcpu)299 static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
300 {
301 unsigned long srcaddr, dstaddr;
302 int reg1, reg2, rc;
303
304 kvm_s390_get_regs_rre(vcpu, ®1, ®2);
305
306 /* Make sure that the source is paged-in */
307 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2],
308 reg2, &srcaddr, 0);
309 if (rc)
310 return kvm_s390_inject_prog_cond(vcpu, rc);
311 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
312 if (rc != 0)
313 return rc;
314
315 /* Make sure that the destination is paged-in */
316 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1],
317 reg1, &dstaddr, 1);
318 if (rc)
319 return kvm_s390_inject_prog_cond(vcpu, rc);
320 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
321 if (rc != 0)
322 return rc;
323
324 kvm_s390_rewind_psw(vcpu, 4);
325
326 return 0;
327 }
328
handle_partial_execution(struct kvm_vcpu * vcpu)329 static int handle_partial_execution(struct kvm_vcpu *vcpu)
330 {
331 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */
332 return handle_mvpg_pei(vcpu);
333 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */
334 return kvm_s390_handle_sigp_pei(vcpu);
335
336 return -EOPNOTSUPP;
337 }
338
kvm_handle_sie_intercept(struct kvm_vcpu * vcpu)339 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
340 {
341 switch (vcpu->arch.sie_block->icptcode) {
342 case 0x00:
343 case 0x10:
344 case 0x18:
345 return handle_noop(vcpu);
346 case 0x04:
347 return handle_instruction(vcpu);
348 case 0x08:
349 return handle_prog(vcpu);
350 case 0x14:
351 return handle_external_interrupt(vcpu);
352 case 0x1c:
353 return kvm_s390_handle_wait(vcpu);
354 case 0x20:
355 return handle_validity(vcpu);
356 case 0x28:
357 return handle_stop(vcpu);
358 case 0x38:
359 return handle_partial_execution(vcpu);
360 default:
361 return -EOPNOTSUPP;
362 }
363 }
364