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 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 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 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 } 102 103 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 } 112 113 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 } 126 127 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_DATA: 169 pgm_info->data_exc_code = vcpu->arch.sie_block->dxc; 170 break; 171 case PGM_PROTECTION: 172 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 173 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 174 break; 175 default: 176 break; 177 } 178 179 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 180 pgm_info->per_code = vcpu->arch.sie_block->perc; 181 pgm_info->per_atmid = vcpu->arch.sie_block->peratmid; 182 pgm_info->per_address = vcpu->arch.sie_block->peraddr; 183 pgm_info->per_access_id = vcpu->arch.sie_block->peraid; 184 } 185 } 186 187 /* 188 * restore ITDB to program-interruption TDB in guest lowcore 189 * and set TX abort indication if required 190 */ 191 static int handle_itdb(struct kvm_vcpu *vcpu) 192 { 193 struct kvm_s390_itdb *itdb; 194 int rc; 195 196 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 197 return 0; 198 if (current->thread.per_flags & PER_FLAG_NO_TE) 199 return 0; 200 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 201 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 202 if (rc) 203 return rc; 204 memset(itdb, 0, sizeof(*itdb)); 205 206 return 0; 207 } 208 209 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 210 211 static int handle_prog(struct kvm_vcpu *vcpu) 212 { 213 struct kvm_s390_pgm_info pgm_info; 214 psw_t psw; 215 int rc; 216 217 vcpu->stat.exit_program_interruption++; 218 219 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 220 kvm_s390_handle_per_event(vcpu); 221 /* the interrupt might have been filtered out completely */ 222 if (vcpu->arch.sie_block->iprcc == 0) 223 return 0; 224 } 225 226 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 227 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 228 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 229 if (rc) 230 return rc; 231 /* Avoid endless loops of specification exceptions */ 232 if (!is_valid_psw(&psw)) 233 return -EOPNOTSUPP; 234 } 235 rc = handle_itdb(vcpu); 236 if (rc) 237 return rc; 238 239 __extract_prog_irq(vcpu, &pgm_info); 240 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 241 } 242 243 static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) 244 { 245 int rc, rc2; 246 247 vcpu->stat.exit_instr_and_program++; 248 rc = handle_instruction(vcpu); 249 rc2 = handle_prog(vcpu); 250 251 if (rc == -EOPNOTSUPP) 252 vcpu->arch.sie_block->icptcode = 0x04; 253 if (rc) 254 return rc; 255 return rc2; 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 &srcaddr, 0); 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 &dstaddr, 1); 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_rewind_psw(vcpu, 4); 339 340 return 0; 341 } 342 343 static int handle_partial_execution(struct kvm_vcpu *vcpu) 344 { 345 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 346 return handle_mvpg_pei(vcpu); 347 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */ 348 return kvm_s390_handle_sigp_pei(vcpu); 349 350 return -EOPNOTSUPP; 351 } 352 353 static const intercept_handler_t intercept_funcs[] = { 354 [0x00 >> 2] = handle_noop, 355 [0x04 >> 2] = handle_instruction, 356 [0x08 >> 2] = handle_prog, 357 [0x0C >> 2] = handle_instruction_and_prog, 358 [0x10 >> 2] = handle_noop, 359 [0x14 >> 2] = handle_external_interrupt, 360 [0x18 >> 2] = handle_noop, 361 [0x1C >> 2] = kvm_s390_handle_wait, 362 [0x20 >> 2] = handle_validity, 363 [0x28 >> 2] = handle_stop, 364 [0x38 >> 2] = handle_partial_execution, 365 }; 366 367 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 368 { 369 intercept_handler_t func; 370 u8 code = vcpu->arch.sie_block->icptcode; 371 372 if (code & 3 || (code >> 2) >= ARRAY_SIZE(intercept_funcs)) 373 return -EOPNOTSUPP; 374 func = intercept_funcs[code >> 2]; 375 if (func) 376 return func(vcpu); 377 return -EOPNOTSUPP; 378 } 379