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