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 [0xaa] = kvm_s390_handle_aa, 33 [0xae] = kvm_s390_handle_sigp, 34 [0xb2] = kvm_s390_handle_b2, 35 [0xb6] = kvm_s390_handle_stctl, 36 [0xb7] = kvm_s390_handle_lctl, 37 [0xb9] = kvm_s390_handle_b9, 38 [0xe5] = kvm_s390_handle_e5, 39 [0xeb] = kvm_s390_handle_eb, 40 }; 41 42 u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu) 43 { 44 struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block; 45 u8 ilen = 0; 46 47 switch (vcpu->arch.sie_block->icptcode) { 48 case ICPT_INST: 49 case ICPT_INSTPROGI: 50 case ICPT_OPEREXC: 51 case ICPT_PARTEXEC: 52 case ICPT_IOINST: 53 /* instruction only stored for these icptcodes */ 54 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8); 55 /* Use the length of the EXECUTE instruction if necessary */ 56 if (sie_block->icptstatus & 1) { 57 ilen = (sie_block->icptstatus >> 4) & 0x6; 58 if (!ilen) 59 ilen = 4; 60 } 61 break; 62 case ICPT_PROGI: 63 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */ 64 ilen = vcpu->arch.sie_block->pgmilc & 0x6; 65 break; 66 } 67 return ilen; 68 } 69 70 static int handle_noop(struct kvm_vcpu *vcpu) 71 { 72 switch (vcpu->arch.sie_block->icptcode) { 73 case 0x10: 74 vcpu->stat.exit_external_request++; 75 break; 76 default: 77 break; /* nothing */ 78 } 79 return 0; 80 } 81 82 static int handle_stop(struct kvm_vcpu *vcpu) 83 { 84 struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; 85 int rc = 0; 86 uint8_t flags, stop_pending; 87 88 vcpu->stat.exit_stop_request++; 89 90 /* delay the stop if any non-stop irq is pending */ 91 if (kvm_s390_vcpu_has_irq(vcpu, 1)) 92 return 0; 93 94 /* avoid races with the injection/SIGP STOP code */ 95 spin_lock(&li->lock); 96 flags = li->irq.stop.flags; 97 stop_pending = kvm_s390_is_stop_irq_pending(vcpu); 98 spin_unlock(&li->lock); 99 100 trace_kvm_s390_stop_request(stop_pending, flags); 101 if (!stop_pending) 102 return 0; 103 104 if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) { 105 rc = kvm_s390_vcpu_store_status(vcpu, 106 KVM_S390_STORE_STATUS_NOADDR); 107 if (rc) 108 return rc; 109 } 110 111 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) 112 kvm_s390_vcpu_stop(vcpu); 113 return -EOPNOTSUPP; 114 } 115 116 static int handle_validity(struct kvm_vcpu *vcpu) 117 { 118 int viwhy = vcpu->arch.sie_block->ipb >> 16; 119 120 vcpu->stat.exit_validity++; 121 trace_kvm_s390_intercept_validity(vcpu, viwhy); 122 KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy, 123 current->pid, vcpu->kvm); 124 125 /* do not warn on invalid runtime instrumentation mode */ 126 WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n", 127 viwhy); 128 return -EINVAL; 129 } 130 131 static int handle_instruction(struct kvm_vcpu *vcpu) 132 { 133 intercept_handler_t handler; 134 135 vcpu->stat.exit_instruction++; 136 trace_kvm_s390_intercept_instruction(vcpu, 137 vcpu->arch.sie_block->ipa, 138 vcpu->arch.sie_block->ipb); 139 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8]; 140 if (handler) 141 return handler(vcpu); 142 return -EOPNOTSUPP; 143 } 144 145 static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu) 146 { 147 struct kvm_s390_pgm_info pgm_info = { 148 .code = vcpu->arch.sie_block->iprcc, 149 /* the PSW has already been rewound */ 150 .flags = KVM_S390_PGM_FLAGS_NO_REWIND, 151 }; 152 153 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) { 154 case PGM_AFX_TRANSLATION: 155 case PGM_ASX_TRANSLATION: 156 case PGM_EX_TRANSLATION: 157 case PGM_LFX_TRANSLATION: 158 case PGM_LSTE_SEQUENCE: 159 case PGM_LSX_TRANSLATION: 160 case PGM_LX_TRANSLATION: 161 case PGM_PRIMARY_AUTHORITY: 162 case PGM_SECONDARY_AUTHORITY: 163 case PGM_SPACE_SWITCH: 164 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 165 break; 166 case PGM_ALEN_TRANSLATION: 167 case PGM_ALE_SEQUENCE: 168 case PGM_ASTE_INSTANCE: 169 case PGM_ASTE_SEQUENCE: 170 case PGM_ASTE_VALIDITY: 171 case PGM_EXTENDED_AUTHORITY: 172 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 173 break; 174 case PGM_ASCE_TYPE: 175 case PGM_PAGE_TRANSLATION: 176 case PGM_REGION_FIRST_TRANS: 177 case PGM_REGION_SECOND_TRANS: 178 case PGM_REGION_THIRD_TRANS: 179 case PGM_SEGMENT_TRANSLATION: 180 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 181 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 182 pgm_info.op_access_id = vcpu->arch.sie_block->oai; 183 break; 184 case PGM_MONITOR: 185 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn; 186 pgm_info.mon_code = vcpu->arch.sie_block->tecmc; 187 break; 188 case PGM_VECTOR_PROCESSING: 189 case PGM_DATA: 190 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc; 191 break; 192 case PGM_PROTECTION: 193 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 194 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 195 break; 196 default: 197 break; 198 } 199 200 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 201 pgm_info.per_code = vcpu->arch.sie_block->perc; 202 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid; 203 pgm_info.per_address = vcpu->arch.sie_block->peraddr; 204 pgm_info.per_access_id = vcpu->arch.sie_block->peraid; 205 } 206 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 207 } 208 209 /* 210 * restore ITDB to program-interruption TDB in guest lowcore 211 * and set TX abort indication if required 212 */ 213 static int handle_itdb(struct kvm_vcpu *vcpu) 214 { 215 struct kvm_s390_itdb *itdb; 216 int rc; 217 218 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 219 return 0; 220 if (current->thread.per_flags & PER_FLAG_NO_TE) 221 return 0; 222 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 223 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 224 if (rc) 225 return rc; 226 memset(itdb, 0, sizeof(*itdb)); 227 228 return 0; 229 } 230 231 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 232 233 static int handle_prog(struct kvm_vcpu *vcpu) 234 { 235 psw_t psw; 236 int rc; 237 238 vcpu->stat.exit_program_interruption++; 239 240 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 241 rc = kvm_s390_handle_per_event(vcpu); 242 if (rc) 243 return rc; 244 /* the interrupt might have been filtered out completely */ 245 if (vcpu->arch.sie_block->iprcc == 0) 246 return 0; 247 } 248 249 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 250 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 251 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 252 if (rc) 253 return rc; 254 /* Avoid endless loops of specification exceptions */ 255 if (!is_valid_psw(&psw)) 256 return -EOPNOTSUPP; 257 } 258 rc = handle_itdb(vcpu); 259 if (rc) 260 return rc; 261 262 return inject_prog_on_prog_intercept(vcpu); 263 } 264 265 /** 266 * handle_external_interrupt - used for external interruption interceptions 267 * 268 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if 269 * the new PSW does not have external interrupts disabled. In the first case, 270 * we've got to deliver the interrupt manually, and in the second case, we 271 * drop to userspace to handle the situation there. 272 */ 273 static int handle_external_interrupt(struct kvm_vcpu *vcpu) 274 { 275 u16 eic = vcpu->arch.sie_block->eic; 276 struct kvm_s390_irq irq; 277 psw_t newpsw; 278 int rc; 279 280 vcpu->stat.exit_external_interrupt++; 281 282 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); 283 if (rc) 284 return rc; 285 /* We can not handle clock comparator or timer interrupt with bad PSW */ 286 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && 287 (newpsw.mask & PSW_MASK_EXT)) 288 return -EOPNOTSUPP; 289 290 switch (eic) { 291 case EXT_IRQ_CLK_COMP: 292 irq.type = KVM_S390_INT_CLOCK_COMP; 293 break; 294 case EXT_IRQ_CPU_TIMER: 295 irq.type = KVM_S390_INT_CPU_TIMER; 296 break; 297 case EXT_IRQ_EXTERNAL_CALL: 298 irq.type = KVM_S390_INT_EXTERNAL_CALL; 299 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr; 300 rc = kvm_s390_inject_vcpu(vcpu, &irq); 301 /* ignore if another external call is already pending */ 302 if (rc == -EBUSY) 303 return 0; 304 return rc; 305 default: 306 return -EOPNOTSUPP; 307 } 308 309 return kvm_s390_inject_vcpu(vcpu, &irq); 310 } 311 312 /** 313 * Handle MOVE PAGE partial execution interception. 314 * 315 * This interception can only happen for guests with DAT disabled and 316 * addresses that are currently not mapped in the host. Thus we try to 317 * set up the mappings for the corresponding user pages here (or throw 318 * addressing exceptions in case of illegal guest addresses). 319 */ 320 static int handle_mvpg_pei(struct kvm_vcpu *vcpu) 321 { 322 unsigned long srcaddr, dstaddr; 323 int reg1, reg2, rc; 324 325 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 326 327 /* Make sure that the source is paged-in */ 328 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2], 329 reg2, &srcaddr, GACC_FETCH); 330 if (rc) 331 return kvm_s390_inject_prog_cond(vcpu, rc); 332 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0); 333 if (rc != 0) 334 return rc; 335 336 /* Make sure that the destination is paged-in */ 337 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1], 338 reg1, &dstaddr, GACC_STORE); 339 if (rc) 340 return kvm_s390_inject_prog_cond(vcpu, rc); 341 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1); 342 if (rc != 0) 343 return rc; 344 345 kvm_s390_retry_instr(vcpu); 346 347 return 0; 348 } 349 350 static int handle_partial_execution(struct kvm_vcpu *vcpu) 351 { 352 vcpu->stat.exit_pei++; 353 354 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 355 return handle_mvpg_pei(vcpu); 356 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */ 357 return kvm_s390_handle_sigp_pei(vcpu); 358 359 return -EOPNOTSUPP; 360 } 361 362 static int handle_operexc(struct kvm_vcpu *vcpu) 363 { 364 psw_t oldpsw, newpsw; 365 int rc; 366 367 vcpu->stat.exit_operation_exception++; 368 trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa, 369 vcpu->arch.sie_block->ipb); 370 371 if (vcpu->arch.sie_block->ipa == 0xb256 && 372 test_kvm_facility(vcpu->kvm, 74)) 373 return handle_sthyi(vcpu); 374 375 if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0) 376 return -EOPNOTSUPP; 377 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &newpsw, sizeof(psw_t)); 378 if (rc) 379 return rc; 380 /* 381 * Avoid endless loops of operation exceptions, if the pgm new 382 * PSW will cause a new operation exception. 383 * The heuristic checks if the pgm new psw is within 6 bytes before 384 * the faulting psw address (with same DAT, AS settings) and the 385 * new psw is not a wait psw and the fault was not triggered by 386 * problem state. 387 */ 388 oldpsw = vcpu->arch.sie_block->gpsw; 389 if (oldpsw.addr - newpsw.addr <= 6 && 390 !(newpsw.mask & PSW_MASK_WAIT) && 391 !(oldpsw.mask & PSW_MASK_PSTATE) && 392 (newpsw.mask & PSW_MASK_ASC) == (oldpsw.mask & PSW_MASK_ASC) && 393 (newpsw.mask & PSW_MASK_DAT) == (oldpsw.mask & PSW_MASK_DAT)) 394 return -EOPNOTSUPP; 395 396 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); 397 } 398 399 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 400 { 401 int rc, per_rc = 0; 402 403 if (kvm_is_ucontrol(vcpu->kvm)) 404 return -EOPNOTSUPP; 405 406 switch (vcpu->arch.sie_block->icptcode) { 407 case 0x10: 408 case 0x18: 409 return handle_noop(vcpu); 410 case 0x04: 411 rc = handle_instruction(vcpu); 412 break; 413 case 0x08: 414 return handle_prog(vcpu); 415 case 0x14: 416 return handle_external_interrupt(vcpu); 417 case 0x1c: 418 return kvm_s390_handle_wait(vcpu); 419 case 0x20: 420 return handle_validity(vcpu); 421 case 0x28: 422 return handle_stop(vcpu); 423 case 0x2c: 424 rc = handle_operexc(vcpu); 425 break; 426 case 0x38: 427 rc = handle_partial_execution(vcpu); 428 break; 429 default: 430 return -EOPNOTSUPP; 431 } 432 433 /* process PER, also if the instrution is processed in user space */ 434 if (vcpu->arch.sie_block->icptstatus & 0x02 && 435 (!rc || rc == -EOPNOTSUPP)) 436 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu); 437 return per_rc ? per_rc : rc; 438 } 439