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 int rc = 0; 72 unsigned int action_bits; 73 74 vcpu->stat.exit_stop_request++; 75 trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits); 76 77 action_bits = vcpu->arch.local_int.action_bits; 78 79 if (!(action_bits & ACTION_STOP_ON_STOP)) 80 return 0; 81 82 if (action_bits & ACTION_STORE_ON_STOP) { 83 rc = kvm_s390_vcpu_store_status(vcpu, 84 KVM_S390_STORE_STATUS_NOADDR); 85 if (rc) 86 return rc; 87 } 88 89 if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm)) 90 kvm_s390_vcpu_stop(vcpu); 91 return -EOPNOTSUPP; 92 } 93 94 static int handle_validity(struct kvm_vcpu *vcpu) 95 { 96 int viwhy = vcpu->arch.sie_block->ipb >> 16; 97 98 vcpu->stat.exit_validity++; 99 trace_kvm_s390_intercept_validity(vcpu, viwhy); 100 WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy); 101 return -EOPNOTSUPP; 102 } 103 104 static int handle_instruction(struct kvm_vcpu *vcpu) 105 { 106 intercept_handler_t handler; 107 108 vcpu->stat.exit_instruction++; 109 trace_kvm_s390_intercept_instruction(vcpu, 110 vcpu->arch.sie_block->ipa, 111 vcpu->arch.sie_block->ipb); 112 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8]; 113 if (handler) 114 return handler(vcpu); 115 return -EOPNOTSUPP; 116 } 117 118 static void __extract_prog_irq(struct kvm_vcpu *vcpu, 119 struct kvm_s390_pgm_info *pgm_info) 120 { 121 memset(pgm_info, 0, sizeof(struct kvm_s390_pgm_info)); 122 pgm_info->code = vcpu->arch.sie_block->iprcc; 123 124 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) { 125 case PGM_AFX_TRANSLATION: 126 case PGM_ASX_TRANSLATION: 127 case PGM_EX_TRANSLATION: 128 case PGM_LFX_TRANSLATION: 129 case PGM_LSTE_SEQUENCE: 130 case PGM_LSX_TRANSLATION: 131 case PGM_LX_TRANSLATION: 132 case PGM_PRIMARY_AUTHORITY: 133 case PGM_SECONDARY_AUTHORITY: 134 case PGM_SPACE_SWITCH: 135 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 136 break; 137 case PGM_ALEN_TRANSLATION: 138 case PGM_ALE_SEQUENCE: 139 case PGM_ASTE_INSTANCE: 140 case PGM_ASTE_SEQUENCE: 141 case PGM_ASTE_VALIDITY: 142 case PGM_EXTENDED_AUTHORITY: 143 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 144 break; 145 case PGM_ASCE_TYPE: 146 case PGM_PAGE_TRANSLATION: 147 case PGM_REGION_FIRST_TRANS: 148 case PGM_REGION_SECOND_TRANS: 149 case PGM_REGION_THIRD_TRANS: 150 case PGM_SEGMENT_TRANSLATION: 151 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 152 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 153 pgm_info->op_access_id = vcpu->arch.sie_block->oai; 154 break; 155 case PGM_MONITOR: 156 pgm_info->mon_class_nr = vcpu->arch.sie_block->mcn; 157 pgm_info->mon_code = vcpu->arch.sie_block->tecmc; 158 break; 159 case PGM_DATA: 160 pgm_info->data_exc_code = vcpu->arch.sie_block->dxc; 161 break; 162 case PGM_PROTECTION: 163 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 164 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 165 break; 166 default: 167 break; 168 } 169 170 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 171 pgm_info->per_code = vcpu->arch.sie_block->perc; 172 pgm_info->per_atmid = vcpu->arch.sie_block->peratmid; 173 pgm_info->per_address = vcpu->arch.sie_block->peraddr; 174 pgm_info->per_access_id = vcpu->arch.sie_block->peraid; 175 } 176 } 177 178 /* 179 * restore ITDB to program-interruption TDB in guest lowcore 180 * and set TX abort indication if required 181 */ 182 static int handle_itdb(struct kvm_vcpu *vcpu) 183 { 184 struct kvm_s390_itdb *itdb; 185 int rc; 186 187 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 188 return 0; 189 if (current->thread.per_flags & PER_FLAG_NO_TE) 190 return 0; 191 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 192 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 193 if (rc) 194 return rc; 195 memset(itdb, 0, sizeof(*itdb)); 196 197 return 0; 198 } 199 200 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 201 202 static int handle_prog(struct kvm_vcpu *vcpu) 203 { 204 struct kvm_s390_pgm_info pgm_info; 205 psw_t psw; 206 int rc; 207 208 vcpu->stat.exit_program_interruption++; 209 210 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 211 kvm_s390_handle_per_event(vcpu); 212 /* the interrupt might have been filtered out completely */ 213 if (vcpu->arch.sie_block->iprcc == 0) 214 return 0; 215 } 216 217 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 218 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 219 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 220 if (rc) 221 return rc; 222 /* Avoid endless loops of specification exceptions */ 223 if (!is_valid_psw(&psw)) 224 return -EOPNOTSUPP; 225 } 226 rc = handle_itdb(vcpu); 227 if (rc) 228 return rc; 229 230 __extract_prog_irq(vcpu, &pgm_info); 231 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 232 } 233 234 static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) 235 { 236 int rc, rc2; 237 238 vcpu->stat.exit_instr_and_program++; 239 rc = handle_instruction(vcpu); 240 rc2 = handle_prog(vcpu); 241 242 if (rc == -EOPNOTSUPP) 243 vcpu->arch.sie_block->icptcode = 0x04; 244 if (rc) 245 return rc; 246 return rc2; 247 } 248 249 /** 250 * handle_external_interrupt - used for external interruption interceptions 251 * 252 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if 253 * the new PSW does not have external interrupts disabled. In the first case, 254 * we've got to deliver the interrupt manually, and in the second case, we 255 * drop to userspace to handle the situation there. 256 */ 257 static int handle_external_interrupt(struct kvm_vcpu *vcpu) 258 { 259 u16 eic = vcpu->arch.sie_block->eic; 260 struct kvm_s390_irq irq; 261 psw_t newpsw; 262 int rc; 263 264 vcpu->stat.exit_external_interrupt++; 265 266 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); 267 if (rc) 268 return rc; 269 /* We can not handle clock comparator or timer interrupt with bad PSW */ 270 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && 271 (newpsw.mask & PSW_MASK_EXT)) 272 return -EOPNOTSUPP; 273 274 switch (eic) { 275 case EXT_IRQ_CLK_COMP: 276 irq.type = KVM_S390_INT_CLOCK_COMP; 277 break; 278 case EXT_IRQ_CPU_TIMER: 279 irq.type = KVM_S390_INT_CPU_TIMER; 280 break; 281 case EXT_IRQ_EXTERNAL_CALL: 282 if (kvm_s390_si_ext_call_pending(vcpu)) 283 return 0; 284 irq.type = KVM_S390_INT_EXTERNAL_CALL; 285 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr; 286 break; 287 default: 288 return -EOPNOTSUPP; 289 } 290 291 return kvm_s390_inject_vcpu(vcpu, &irq); 292 } 293 294 /** 295 * Handle MOVE PAGE partial execution interception. 296 * 297 * This interception can only happen for guests with DAT disabled and 298 * addresses that are currently not mapped in the host. Thus we try to 299 * set up the mappings for the corresponding user pages here (or throw 300 * addressing exceptions in case of illegal guest addresses). 301 */ 302 static int handle_mvpg_pei(struct kvm_vcpu *vcpu) 303 { 304 unsigned long srcaddr, dstaddr; 305 int reg1, reg2, rc; 306 307 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 308 309 /* Make sure that the source is paged-in */ 310 srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]); 311 if (kvm_is_error_gpa(vcpu->kvm, srcaddr)) 312 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 313 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0); 314 if (rc != 0) 315 return rc; 316 317 /* Make sure that the destination is paged-in */ 318 dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]); 319 if (kvm_is_error_gpa(vcpu->kvm, dstaddr)) 320 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 321 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1); 322 if (rc != 0) 323 return rc; 324 325 kvm_s390_rewind_psw(vcpu, 4); 326 327 return 0; 328 } 329 330 static int handle_partial_execution(struct kvm_vcpu *vcpu) 331 { 332 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 333 return handle_mvpg_pei(vcpu); 334 if (vcpu->arch.sie_block->ipa >> 8 == 0xae) /* SIGP */ 335 return kvm_s390_handle_sigp_pei(vcpu); 336 337 return -EOPNOTSUPP; 338 } 339 340 static const intercept_handler_t intercept_funcs[] = { 341 [0x00 >> 2] = handle_noop, 342 [0x04 >> 2] = handle_instruction, 343 [0x08 >> 2] = handle_prog, 344 [0x0C >> 2] = handle_instruction_and_prog, 345 [0x10 >> 2] = handle_noop, 346 [0x14 >> 2] = handle_external_interrupt, 347 [0x18 >> 2] = handle_noop, 348 [0x1C >> 2] = kvm_s390_handle_wait, 349 [0x20 >> 2] = handle_validity, 350 [0x28 >> 2] = handle_stop, 351 [0x38 >> 2] = handle_partial_execution, 352 }; 353 354 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 355 { 356 intercept_handler_t func; 357 u8 code = vcpu->arch.sie_block->icptcode; 358 359 if (code & 3 || (code >> 2) >= ARRAY_SIZE(intercept_funcs)) 360 return -EOPNOTSUPP; 361 func = intercept_funcs[code >> 2]; 362 if (func) 363 return func(vcpu); 364 return -EOPNOTSUPP; 365 } 366