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 static int handle_noop(struct kvm_vcpu *vcpu) 42 { 43 switch (vcpu->arch.sie_block->icptcode) { 44 case 0x0: 45 vcpu->stat.exit_null++; 46 break; 47 case 0x10: 48 vcpu->stat.exit_external_request++; 49 break; 50 default: 51 break; /* nothing */ 52 } 53 return 0; 54 } 55 56 static int handle_stop(struct kvm_vcpu *vcpu) 57 { 58 int rc = 0; 59 60 vcpu->stat.exit_stop_request++; 61 spin_lock_bh(&vcpu->arch.local_int.lock); 62 63 trace_kvm_s390_stop_request(vcpu->arch.local_int.action_bits); 64 65 if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) { 66 kvm_s390_vcpu_stop(vcpu); 67 vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP; 68 VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); 69 rc = -EOPNOTSUPP; 70 } 71 72 if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) { 73 vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP; 74 /* store status must be called unlocked. Since local_int.lock 75 * only protects local_int.* and not guest memory we can give 76 * up the lock here */ 77 spin_unlock_bh(&vcpu->arch.local_int.lock); 78 rc = kvm_s390_vcpu_store_status(vcpu, 79 KVM_S390_STORE_STATUS_NOADDR); 80 if (rc >= 0) 81 rc = -EOPNOTSUPP; 82 } else 83 spin_unlock_bh(&vcpu->arch.local_int.lock); 84 return rc; 85 } 86 87 static int handle_validity(struct kvm_vcpu *vcpu) 88 { 89 int viwhy = vcpu->arch.sie_block->ipb >> 16; 90 91 vcpu->stat.exit_validity++; 92 trace_kvm_s390_intercept_validity(vcpu, viwhy); 93 WARN_ONCE(true, "kvm: unhandled validity intercept 0x%x\n", viwhy); 94 return -EOPNOTSUPP; 95 } 96 97 static int handle_instruction(struct kvm_vcpu *vcpu) 98 { 99 intercept_handler_t handler; 100 101 vcpu->stat.exit_instruction++; 102 trace_kvm_s390_intercept_instruction(vcpu, 103 vcpu->arch.sie_block->ipa, 104 vcpu->arch.sie_block->ipb); 105 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8]; 106 if (handler) 107 return handler(vcpu); 108 return -EOPNOTSUPP; 109 } 110 111 static void __extract_prog_irq(struct kvm_vcpu *vcpu, 112 struct kvm_s390_pgm_info *pgm_info) 113 { 114 memset(pgm_info, 0, sizeof(struct kvm_s390_pgm_info)); 115 pgm_info->code = vcpu->arch.sie_block->iprcc; 116 117 switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) { 118 case PGM_AFX_TRANSLATION: 119 case PGM_ASX_TRANSLATION: 120 case PGM_EX_TRANSLATION: 121 case PGM_LFX_TRANSLATION: 122 case PGM_LSTE_SEQUENCE: 123 case PGM_LSX_TRANSLATION: 124 case PGM_LX_TRANSLATION: 125 case PGM_PRIMARY_AUTHORITY: 126 case PGM_SECONDARY_AUTHORITY: 127 case PGM_SPACE_SWITCH: 128 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 129 break; 130 case PGM_ALEN_TRANSLATION: 131 case PGM_ALE_SEQUENCE: 132 case PGM_ASTE_INSTANCE: 133 case PGM_ASTE_SEQUENCE: 134 case PGM_ASTE_VALIDITY: 135 case PGM_EXTENDED_AUTHORITY: 136 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 137 break; 138 case PGM_ASCE_TYPE: 139 case PGM_PAGE_TRANSLATION: 140 case PGM_REGION_FIRST_TRANS: 141 case PGM_REGION_SECOND_TRANS: 142 case PGM_REGION_THIRD_TRANS: 143 case PGM_SEGMENT_TRANSLATION: 144 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 145 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 146 pgm_info->op_access_id = vcpu->arch.sie_block->oai; 147 break; 148 case PGM_MONITOR: 149 pgm_info->mon_class_nr = vcpu->arch.sie_block->mcn; 150 pgm_info->mon_code = vcpu->arch.sie_block->tecmc; 151 break; 152 case PGM_DATA: 153 pgm_info->data_exc_code = vcpu->arch.sie_block->dxc; 154 break; 155 case PGM_PROTECTION: 156 pgm_info->trans_exc_code = vcpu->arch.sie_block->tecmc; 157 pgm_info->exc_access_id = vcpu->arch.sie_block->eai; 158 break; 159 default: 160 break; 161 } 162 163 if (vcpu->arch.sie_block->iprcc & PGM_PER) { 164 pgm_info->per_code = vcpu->arch.sie_block->perc; 165 pgm_info->per_atmid = vcpu->arch.sie_block->peratmid; 166 pgm_info->per_address = vcpu->arch.sie_block->peraddr; 167 pgm_info->per_access_id = vcpu->arch.sie_block->peraid; 168 } 169 } 170 171 /* 172 * restore ITDB to program-interruption TDB in guest lowcore 173 * and set TX abort indication if required 174 */ 175 static int handle_itdb(struct kvm_vcpu *vcpu) 176 { 177 struct kvm_s390_itdb *itdb; 178 int rc; 179 180 if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu)) 181 return 0; 182 if (current->thread.per_flags & PER_FLAG_NO_TE) 183 return 0; 184 itdb = (struct kvm_s390_itdb *)vcpu->arch.sie_block->itdba; 185 rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb)); 186 if (rc) 187 return rc; 188 memset(itdb, 0, sizeof(*itdb)); 189 190 return 0; 191 } 192 193 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER) 194 195 static int handle_prog(struct kvm_vcpu *vcpu) 196 { 197 struct kvm_s390_pgm_info pgm_info; 198 psw_t psw; 199 int rc; 200 201 vcpu->stat.exit_program_interruption++; 202 203 if (guestdbg_enabled(vcpu) && per_event(vcpu)) { 204 kvm_s390_handle_per_event(vcpu); 205 /* the interrupt might have been filtered out completely */ 206 if (vcpu->arch.sie_block->iprcc == 0) 207 return 0; 208 } 209 210 trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc); 211 if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) { 212 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t)); 213 if (rc) 214 return rc; 215 /* Avoid endless loops of specification exceptions */ 216 if (!is_valid_psw(&psw)) 217 return -EOPNOTSUPP; 218 } 219 rc = handle_itdb(vcpu); 220 if (rc) 221 return rc; 222 223 __extract_prog_irq(vcpu, &pgm_info); 224 return kvm_s390_inject_prog_irq(vcpu, &pgm_info); 225 } 226 227 static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) 228 { 229 int rc, rc2; 230 231 vcpu->stat.exit_instr_and_program++; 232 rc = handle_instruction(vcpu); 233 rc2 = handle_prog(vcpu); 234 235 if (rc == -EOPNOTSUPP) 236 vcpu->arch.sie_block->icptcode = 0x04; 237 if (rc) 238 return rc; 239 return rc2; 240 } 241 242 /** 243 * handle_external_interrupt - used for external interruption interceptions 244 * 245 * This interception only occurs if the CPUSTAT_EXT_INT bit was set, or if 246 * the new PSW does not have external interrupts disabled. In the first case, 247 * we've got to deliver the interrupt manually, and in the second case, we 248 * drop to userspace to handle the situation there. 249 */ 250 static int handle_external_interrupt(struct kvm_vcpu *vcpu) 251 { 252 u16 eic = vcpu->arch.sie_block->eic; 253 struct kvm_s390_interrupt irq; 254 psw_t newpsw; 255 int rc; 256 257 vcpu->stat.exit_external_interrupt++; 258 259 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t)); 260 if (rc) 261 return rc; 262 /* We can not handle clock comparator or timer interrupt with bad PSW */ 263 if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) && 264 (newpsw.mask & PSW_MASK_EXT)) 265 return -EOPNOTSUPP; 266 267 switch (eic) { 268 case EXT_IRQ_CLK_COMP: 269 irq.type = KVM_S390_INT_CLOCK_COMP; 270 break; 271 case EXT_IRQ_CPU_TIMER: 272 irq.type = KVM_S390_INT_CPU_TIMER; 273 break; 274 case EXT_IRQ_EXTERNAL_CALL: 275 irq.type = KVM_S390_INT_EXTERNAL_CALL; 276 irq.parm = vcpu->arch.sie_block->extcpuaddr; 277 break; 278 default: 279 return -EOPNOTSUPP; 280 } 281 282 return kvm_s390_inject_vcpu(vcpu, &irq); 283 } 284 285 /** 286 * Handle MOVE PAGE partial execution interception. 287 * 288 * This interception can only happen for guests with DAT disabled and 289 * addresses that are currently not mapped in the host. Thus we try to 290 * set up the mappings for the corresponding user pages here (or throw 291 * addressing exceptions in case of illegal guest addresses). 292 */ 293 static int handle_mvpg_pei(struct kvm_vcpu *vcpu) 294 { 295 psw_t *psw = &vcpu->arch.sie_block->gpsw; 296 unsigned long srcaddr, dstaddr; 297 int reg1, reg2, rc; 298 299 kvm_s390_get_regs_rre(vcpu, ®1, ®2); 300 301 /* Make sure that the source is paged-in */ 302 srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]); 303 if (kvm_is_error_gpa(vcpu->kvm, srcaddr)) 304 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 305 rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0); 306 if (rc != 0) 307 return rc; 308 309 /* Make sure that the destination is paged-in */ 310 dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]); 311 if (kvm_is_error_gpa(vcpu->kvm, dstaddr)) 312 return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 313 rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1); 314 if (rc != 0) 315 return rc; 316 317 psw->addr = __rewind_psw(*psw, 4); 318 319 return 0; 320 } 321 322 static int handle_partial_execution(struct kvm_vcpu *vcpu) 323 { 324 if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */ 325 return handle_mvpg_pei(vcpu); 326 327 return -EOPNOTSUPP; 328 } 329 330 static const intercept_handler_t intercept_funcs[] = { 331 [0x00 >> 2] = handle_noop, 332 [0x04 >> 2] = handle_instruction, 333 [0x08 >> 2] = handle_prog, 334 [0x0C >> 2] = handle_instruction_and_prog, 335 [0x10 >> 2] = handle_noop, 336 [0x14 >> 2] = handle_external_interrupt, 337 [0x18 >> 2] = handle_noop, 338 [0x1C >> 2] = kvm_s390_handle_wait, 339 [0x20 >> 2] = handle_validity, 340 [0x28 >> 2] = handle_stop, 341 [0x38 >> 2] = handle_partial_execution, 342 }; 343 344 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 345 { 346 intercept_handler_t func; 347 u8 code = vcpu->arch.sie_block->icptcode; 348 349 if (code & 3 || (code >> 2) >= ARRAY_SIZE(intercept_funcs)) 350 return -EOPNOTSUPP; 351 func = intercept_funcs[code >> 2]; 352 if (func) 353 return func(vcpu); 354 return -EOPNOTSUPP; 355 } 356