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 WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy); 123 return -EOPNOTSUPP; 124 } 125 126 static int handle_instruction(struct kvm_vcpu *vcpu) 127 { 128 intercept_handler_t handler; 129 130 vcpu->stat.exit_instruction++; 131 trace_kvm_s390_intercept_instruction(vcpu, 132 vcpu->arch.sie_block->ipa, 133 vcpu->arch.sie_block->ipb); 134 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8]; 135 if (handler) 136 return handler(vcpu); 137 return -EOPNOTSUPP; 138 } 139 140 static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu) 141 { 142 struct kvm_s390_pgm_info pgm_info = { 143 .code = vcpu->arch.sie_block->iprcc, 144 /* the PSW has already been rewound */ 145 .flags = KVM_S390_PGM_FLAGS_NO_REWIND, 146 }; 147 148 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) { 149 case PGM_AFX_TRANSLATION: 150 case PGM_ASX_TRANSLATION: 151 case PGM_EX_TRANSLATION: 152 case PGM_LFX_TRANSLATION: 153 case PGM_LSTE_SEQUENCE: 154 case PGM_LSX_TRANSLATION: 155 case PGM_LX_TRANSLATION: 156 case PGM_PRIMARY_AUTHORITY: 157 case PGM_SECONDARY_AUTHORITY: 158 case PGM_SPACE_SWITCH: 159 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 160 break; 161 case PGM_ALEN_TRANSLATION: 162 case PGM_ALE_SEQUENCE: 163 case PGM_ASTE_INSTANCE: 164 case PGM_ASTE_SEQUENCE: 165 case PGM_ASTE_VALIDITY: 166 case PGM_EXTENDED_AUTHORITY: 167 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 168 break; 169 case PGM_ASCE_TYPE: 170 case PGM_PAGE_TRANSLATION: 171 case PGM_REGION_FIRST_TRANS: 172 case PGM_REGION_SECOND_TRANS: 173 case PGM_REGION_THIRD_TRANS: 174 case PGM_SEGMENT_TRANSLATION: 175 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 176 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 177 pgm_info.op_access_id = vcpu->arch.sie_block->oai; 178 break; 179 case PGM_MONITOR: 180 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn; 181 pgm_info.mon_code = vcpu->arch.sie_block->tecmc; 182 break; 183 case PGM_VECTOR_PROCESSING: 184 case PGM_DATA: 185 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc; 186 break; 187 case PGM_PROTECTION: 188 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc; 189 pgm_info.exc_access_id = vcpu->arch.sie_block->eai; 190 break; 191 default: 192 break; 193 } 194 195 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 196 pgm_info.per_code = vcpu->arch.sie_block->perc; 197 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid; 198 pgm_info.per_address = vcpu->arch.sie_block->peraddr; 199 pgm_info.per_access_id = vcpu->arch.sie_block->peraid; 200 } 201 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 202 } 203 204 /* 205 * restore ITDB to program-interruption TDB in guest lowcore 206 * and set TX abort indication if required 207 */ 208 static int handle_itdb(struct kvm_vcpu *vcpu) 209 { 210 struct kvm_s390_itdb *itdb; 211 int rc; 212 213 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 214 return 0; 215 if (current->thread.per_flags & PER_FLAG_NO_TE) 216 return 0; 217 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 218 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 219 if (rc) 220 return rc; 221 memset(itdb, 0, sizeof(*itdb)); 222 223 return 0; 224 } 225 226 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 227 228 static int handle_prog(struct kvm_vcpu *vcpu) 229 { 230 psw_t psw; 231 int rc; 232 233 vcpu->stat.exit_program_interruption++; 234 235 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 236 kvm_s390_handle_per_event(vcpu); 237 /* the interrupt might have been filtered out completely */ 238 if (vcpu->arch.sie_block->iprcc == 0) 239 return 0; 240 } 241 242 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 243 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 244 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 245 if (rc) 246 return rc; 247 /* Avoid endless loops of specification exceptions */ 248 if (!is_valid_psw(&psw)) 249 return -EOPNOTSUPP; 250 } 251 rc = handle_itdb(vcpu); 252 if (rc) 253 return rc; 254 255 return inject_prog_on_prog_intercept(vcpu); 256 } 257 258 /** 259 * handle_external_interrupt - used for external interruption interceptions 260 * 261 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if 262 * the new PSW does not have external interrupts disabled. In the first case, 263 * we've got to deliver the interrupt manually, and in the second case, we 264 * drop to userspace to handle the situation there. 265 */ 266 static int handle_external_interrupt(struct kvm_vcpu *vcpu) 267 { 268 u16 eic = vcpu->arch.sie_block->eic; 269 struct kvm_s390_irq irq; 270 psw_t newpsw; 271 int rc; 272 273 vcpu->stat.exit_external_interrupt++; 274 275 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); 276 if (rc) 277 return rc; 278 /* We can not handle clock comparator or timer interrupt with bad PSW */ 279 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && 280 (newpsw.mask & PSW_MASK_EXT)) 281 return -EOPNOTSUPP; 282 283 switch (eic) { 284 case EXT_IRQ_CLK_COMP: 285 irq.type = KVM_S390_INT_CLOCK_COMP; 286 break; 287 case EXT_IRQ_CPU_TIMER: 288 irq.type = KVM_S390_INT_CPU_TIMER; 289 break; 290 case EXT_IRQ_EXTERNAL_CALL: 291 irq.type = KVM_S390_INT_EXTERNAL_CALL; 292 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr; 293 rc = kvm_s390_inject_vcpu(vcpu, &irq); 294 /* ignore if another external call is already pending */ 295 if (rc == -EBUSY) 296 return 0; 297 return rc; 298 default: 299 return -EOPNOTSUPP; 300 } 301 302 return kvm_s390_inject_vcpu(vcpu, &irq); 303 } 304 305 /** 306 * Handle MOVE PAGE partial execution interception. 307 * 308 * This interception can only happen for guests with DAT disabled and 309 * addresses that are currently not mapped in the host. Thus we try to 310 * set up the mappings for the corresponding user pages here (or throw 311 * addressing exceptions in case of illegal guest addresses). 312 */ 313 static int handle_mvpg_pei(struct kvm_vcpu *vcpu) 314 { 315 unsigned long srcaddr, dstaddr; 316 int reg1, reg2, rc; 317 318 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 319 320 /* Make sure that the source is paged-in */ 321 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg2], 322 reg2, &srcaddr, GACC_FETCH); 323 if (rc) 324 return kvm_s390_inject_prog_cond(vcpu, rc); 325 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0); 326 if (rc != 0) 327 return rc; 328 329 /* Make sure that the destination is paged-in */ 330 rc = guest_translate_address(vcpu, vcpu->run->s.regs.gprs[reg1], 331 reg1, &dstaddr, GACC_STORE); 332 if (rc) 333 return kvm_s390_inject_prog_cond(vcpu, rc); 334 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1); 335 if (rc != 0) 336 return rc; 337 338 kvm_s390_retry_instr(vcpu); 339 340 return 0; 341 } 342 343 static int handle_partial_execution(struct kvm_vcpu *vcpu) 344 { 345 vcpu->stat.exit_pei++; 346 347 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 348 return handle_mvpg_pei(vcpu); 349 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */ 350 return kvm_s390_handle_sigp_pei(vcpu); 351 352 return -EOPNOTSUPP; 353 } 354 355 static int handle_operexc(struct kvm_vcpu *vcpu) 356 { 357 vcpu->stat.exit_operation_exception++; 358 trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa, 359 vcpu->arch.sie_block->ipb); 360 361 if (vcpu->arch.sie_block->ipa == 0xb256 && 362 test_kvm_facility(vcpu->kvm, 74)) 363 return handle_sthyi(vcpu); 364 365 if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0) 366 return -EOPNOTSUPP; 367 368 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); 369 } 370 371 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 372 { 373 int rc, per_rc = 0; 374 375 if (kvm_is_ucontrol(vcpu->kvm)) 376 return -EOPNOTSUPP; 377 378 switch (vcpu->arch.sie_block->icptcode) { 379 case 0x10: 380 case 0x18: 381 return handle_noop(vcpu); 382 case 0x04: 383 rc = handle_instruction(vcpu); 384 break; 385 case 0x08: 386 return handle_prog(vcpu); 387 case 0x14: 388 return handle_external_interrupt(vcpu); 389 case 0x1c: 390 return kvm_s390_handle_wait(vcpu); 391 case 0x20: 392 return handle_validity(vcpu); 393 case 0x28: 394 return handle_stop(vcpu); 395 case 0x2c: 396 rc = handle_operexc(vcpu); 397 break; 398 case 0x38: 399 rc = handle_partial_execution(vcpu); 400 break; 401 default: 402 return -EOPNOTSUPP; 403 } 404 405 /* process PER, also if the instrution is processed in user space */ 406 if (vcpu->arch.sie_block->icptstatus & 0x02 && 407 (!rc || rc == -EOPNOTSUPP)) 408 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu); 409 return per_rc ? per_rc : rc; 410 } 411