arch/s390/kvm/sigp.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * handling interprocessor communication
   4  *
   5  * Copyright IBM Corp. 2008, 2013
   6  *
   7  *    Author(s): Carsten Otte <[email protected]>
   8  *               Christian Borntraeger <[email protected]>
   9  *               Christian Ehrhardt <[email protected]>
  10  */
  11
  12 #include <linux/kvm.h>
  13 #include <linux/kvm_host.h>
  14 #include <linux/slab.h>
  15 #include <asm/sigp.h>
  16 #include "gaccess.h"
  17 #include "kvm-s390.h"
  18 #include "trace.h"
  19
  20 static int __sigp_sense(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
  21                         u64 *reg)
  22 {
  23         const bool stopped = kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED);
  24         int rc;
  25         int ext_call_pending;
  26
  27         ext_call_pending = kvm_s390_ext_call_pending(dst_vcpu);
  28         if (!stopped && !ext_call_pending)
  29                 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
  30         else {
  31                 *reg &= 0xffffffff00000000UL;
  32                 if (ext_call_pending)
  33                         *reg |= SIGP_STATUS_EXT_CALL_PENDING;
  34                 if (stopped)
  35                         *reg |= SIGP_STATUS_STOPPED;
  36                 rc = SIGP_CC_STATUS_STORED;
  37         }
  38
  39         VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", dst_vcpu->vcpu_id,
  40                    rc);
  41         return rc;
  42 }
  43
  44 static int __inject_sigp_emergency(struct kvm_vcpu *vcpu,
  45                                     struct kvm_vcpu *dst_vcpu)
  46 {
  47         struct kvm_s390_irq irq = {
  48                 .type = KVM_S390_INT_EMERGENCY,
  49                 .u.emerg.code = vcpu->vcpu_id,
  50         };
  51         int rc = 0;
  52
  53         rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
  54         if (!rc)
  55                 VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x",
  56                            dst_vcpu->vcpu_id);
  57
  58         return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
  59 }
  60
  61 static int __sigp_emergency(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
  62 {
  63         return __inject_sigp_emergency(vcpu, dst_vcpu);
  64 }
  65
  66 static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu,
  67                                         struct kvm_vcpu *dst_vcpu,
  68                                         u16 asn, u64 *reg)
  69 {
  70         const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
  71         u16 p_asn, s_asn;
  72         psw_t *psw;
  73         bool idle;
  74
  75         idle = is_vcpu_idle(vcpu);
  76         psw = &dst_vcpu->arch.sie_block->gpsw;
  77         p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff;  /* Primary ASN */
  78         s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff;  /* Secondary ASN */
  79
  80         /* Inject the emergency signal? */
  81         if (!is_vcpu_stopped(vcpu)
  82             || (psw->mask & psw_int_mask) != psw_int_mask
  83             || (idle && psw->addr != 0)
  84             || (!idle && (asn == p_asn || asn == s_asn))) {
  85                 return __inject_sigp_emergency(vcpu, dst_vcpu);
  86         } else {
  87                 *reg &= 0xffffffff00000000UL;
  88                 *reg |= SIGP_STATUS_INCORRECT_STATE;
  89                 return SIGP_CC_STATUS_STORED;
  90         }
  91 }
  92
  93 static int __sigp_external_call(struct kvm_vcpu *vcpu,
  94                                 struct kvm_vcpu *dst_vcpu, u64 *reg)
  95 {
  96         struct kvm_s390_irq irq = {
  97                 .type = KVM_S390_INT_EXTERNAL_CALL,
  98                 .u.extcall.code = vcpu->vcpu_id,
  99         };
 100         int rc;
 101
 102         rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
 103         if (rc == -EBUSY) {
 104                 *reg &= 0xffffffff00000000UL;
 105                 *reg |= SIGP_STATUS_EXT_CALL_PENDING;
 106                 return SIGP_CC_STATUS_STORED;
 107         } else if (rc == 0) {
 108                 VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x",
 109                            dst_vcpu->vcpu_id);
 110         }
 111
 112         return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
 113 }
 114
 115 static int __sigp_stop(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu)
 116 {
 117         struct kvm_s390_irq irq = {
 118                 .type = KVM_S390_SIGP_STOP,
 119         };
 120         int rc;
 121
 122         rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
 123         if (rc == -EBUSY)
 124                 rc = SIGP_CC_BUSY;
 125         else if (rc == 0)
 126                 VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x",
 127                            dst_vcpu->vcpu_id);
 128
 129         return rc;
 130 }
 131
 132 static int __sigp_stop_and_store_status(struct kvm_vcpu *vcpu,
 133                                         struct kvm_vcpu *dst_vcpu, u64 *reg)
 134 {
 135         struct kvm_s390_irq irq = {
 136                 .type = KVM_S390_SIGP_STOP,
 137                 .u.stop.flags = KVM_S390_STOP_FLAG_STORE_STATUS,
 138         };
 139         int rc;
 140
 141         rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
 142         if (rc == -EBUSY)
 143                 rc = SIGP_CC_BUSY;
 144         else if (rc == 0)
 145                 VCPU_EVENT(vcpu, 4, "sent sigp stop and store status to cpu %x",
 146                            dst_vcpu->vcpu_id);
 147
 148         return rc;
 149 }
 150
 151 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter,
 152                            u64 *status_reg)
 153 {
 154         *status_reg &= 0xffffffff00000000UL;
 155
 156         /* Reject set arch order, with czam we're always in z/Arch mode. */
 157         *status_reg |= SIGP_STATUS_INVALID_PARAMETER;
 158         return SIGP_CC_STATUS_STORED;
 159 }
 160
 161 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, struct kvm_vcpu *dst_vcpu,
 162                              u32 address, u64 *reg)
 163 {
 164         struct kvm_s390_irq irq = {
 165                 .type = KVM_S390_SIGP_SET_PREFIX,
 166                 .u.prefix.address = address & 0x7fffe000u,
 167         };
 168         int rc;
 169
 170         /*
 171          * Make sure the new value is valid memory. We only need to check the
 172          * first page, since address is 8k aligned and memory pieces are always
 173          * at least 1MB aligned and have at least a size of 1MB.
 174          */
 175         if (kvm_is_error_gpa(vcpu->kvm, irq.u.prefix.address)) {
 176                 *reg &= 0xffffffff00000000UL;
 177                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
 178                 return SIGP_CC_STATUS_STORED;
 179         }
 180
 181         rc = kvm_s390_inject_vcpu(dst_vcpu, &irq);
 182         if (rc == -EBUSY) {
 183                 *reg &= 0xffffffff00000000UL;
 184                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 185                 return SIGP_CC_STATUS_STORED;
 186         }
 187
 188         return rc;
 189 }
 190
 191 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu,
 192                                        struct kvm_vcpu *dst_vcpu,
 193                                        u32 addr, u64 *reg)
 194 {
 195         int rc;
 196
 197         if (!kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_STOPPED)) {
 198                 *reg &= 0xffffffff00000000UL;
 199                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 200                 return SIGP_CC_STATUS_STORED;
 201         }
 202
 203         addr &= 0x7ffffe00;
 204         rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
 205         if (rc == -EFAULT) {
 206                 *reg &= 0xffffffff00000000UL;
 207                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
 208                 rc = SIGP_CC_STATUS_STORED;
 209         }
 210         return rc;
 211 }
 212
 213 static int __sigp_sense_running(struct kvm_vcpu *vcpu,
 214                                 struct kvm_vcpu *dst_vcpu, u64 *reg)
 215 {
 216         int rc;
 217
 218         if (!test_kvm_facility(vcpu->kvm, 9)) {
 219                 *reg &= 0xffffffff00000000UL;
 220                 *reg |= SIGP_STATUS_INVALID_ORDER;
 221                 return SIGP_CC_STATUS_STORED;
 222         }
 223
 224         if (kvm_s390_test_cpuflags(dst_vcpu, CPUSTAT_RUNNING)) {
 225                 /* running */
 226                 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 227         } else {
 228                 /* not running */
 229                 *reg &= 0xffffffff00000000UL;
 230                 *reg |= SIGP_STATUS_NOT_RUNNING;
 231                 rc = SIGP_CC_STATUS_STORED;
 232         }
 233
 234         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x",
 235                    dst_vcpu->vcpu_id, rc);
 236
 237         return rc;
 238 }
 239
 240 static int __prepare_sigp_re_start(struct kvm_vcpu *vcpu,
 241                                    struct kvm_vcpu *dst_vcpu, u8 order_code)
 242 {
 243         struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
 244         /* handle (RE)START in user space */
 245         int rc = -EOPNOTSUPP;
 246
 247         /* make sure we don't race with STOP irq injection */
 248         spin_lock(&li->lock);
 249         if (kvm_s390_is_stop_irq_pending(dst_vcpu))
 250                 rc = SIGP_CC_BUSY;
 251         spin_unlock(&li->lock);
 252
 253         return rc;
 254 }
 255
 256 static int __prepare_sigp_cpu_reset(struct kvm_vcpu *vcpu,
 257                                     struct kvm_vcpu *dst_vcpu, u8 order_code)
 258 {
 259         /* handle (INITIAL) CPU RESET in user space */
 260         return -EOPNOTSUPP;
 261 }
 262
 263 static int __prepare_sigp_unknown(struct kvm_vcpu *vcpu,
 264                                   struct kvm_vcpu *dst_vcpu)
 265 {
 266         /* handle unknown orders in user space */
 267         return -EOPNOTSUPP;
 268 }
 269
 270 static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
 271                            u16 cpu_addr, u32 parameter, u64 *status_reg)
 272 {
 273         int rc;
 274         struct kvm_vcpu *dst_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
 275
 276         if (!dst_vcpu)
 277                 return SIGP_CC_NOT_OPERATIONAL;
 278
 279         switch (order_code) {
 280         case SIGP_SENSE:
 281                 vcpu->stat.instruction_sigp_sense++;
 282                 rc = __sigp_sense(vcpu, dst_vcpu, status_reg);
 283                 break;
 284         case SIGP_EXTERNAL_CALL:
 285                 vcpu->stat.instruction_sigp_external_call++;
 286                 rc = __sigp_external_call(vcpu, dst_vcpu, status_reg);
 287                 break;
 288         case SIGP_EMERGENCY_SIGNAL:
 289                 vcpu->stat.instruction_sigp_emergency++;
 290                 rc = __sigp_emergency(vcpu, dst_vcpu);
 291                 break;
 292         case SIGP_STOP:
 293                 vcpu->stat.instruction_sigp_stop++;
 294                 rc = __sigp_stop(vcpu, dst_vcpu);
 295                 break;
 296         case SIGP_STOP_AND_STORE_STATUS:
 297                 vcpu->stat.instruction_sigp_stop_store_status++;
 298                 rc = __sigp_stop_and_store_status(vcpu, dst_vcpu, status_reg);
 299                 break;
 300         case SIGP_STORE_STATUS_AT_ADDRESS:
 301                 vcpu->stat.instruction_sigp_store_status++;
 302                 rc = __sigp_store_status_at_addr(vcpu, dst_vcpu, parameter,
 303                                                  status_reg);
 304                 break;
 305         case SIGP_SET_PREFIX:
 306                 vcpu->stat.instruction_sigp_prefix++;
 307                 rc = __sigp_set_prefix(vcpu, dst_vcpu, parameter, status_reg);
 308                 break;
 309         case SIGP_COND_EMERGENCY_SIGNAL:
 310                 vcpu->stat.instruction_sigp_cond_emergency++;
 311                 rc = __sigp_conditional_emergency(vcpu, dst_vcpu, parameter,
 312                                                   status_reg);
 313                 break;
 314         case SIGP_SENSE_RUNNING:
 315                 vcpu->stat.instruction_sigp_sense_running++;
 316                 rc = __sigp_sense_running(vcpu, dst_vcpu, status_reg);
 317                 break;
 318         case SIGP_START:
 319                 vcpu->stat.instruction_sigp_start++;
 320                 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
 321                 break;
 322         case SIGP_RESTART:
 323                 vcpu->stat.instruction_sigp_restart++;
 324                 rc = __prepare_sigp_re_start(vcpu, dst_vcpu, order_code);
 325                 break;
 326         case SIGP_INITIAL_CPU_RESET:
 327                 vcpu->stat.instruction_sigp_init_cpu_reset++;
 328                 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
 329                 break;
 330         case SIGP_CPU_RESET:
 331                 vcpu->stat.instruction_sigp_cpu_reset++;
 332                 rc = __prepare_sigp_cpu_reset(vcpu, dst_vcpu, order_code);
 333                 break;
 334         default:
 335                 vcpu->stat.instruction_sigp_unknown++;
 336                 rc = __prepare_sigp_unknown(vcpu, dst_vcpu);
 337         }
 338
 339         if (rc == -EOPNOTSUPP)
 340                 VCPU_EVENT(vcpu, 4,
 341                            "sigp order %u -> cpu %x: handled in user space",
 342                            order_code, dst_vcpu->vcpu_id);
 343
 344         return rc;
 345 }
 346
 347 static int handle_sigp_order_in_user_space(struct kvm_vcpu *vcpu, u8 order_code,
 348                                            u16 cpu_addr)
 349 {
 350         if (!vcpu->kvm->arch.user_sigp)
 351                 return 0;
 352
 353         switch (order_code) {
 354         case SIGP_SENSE:
 355         case SIGP_EXTERNAL_CALL:
 356         case SIGP_EMERGENCY_SIGNAL:
 357         case SIGP_COND_EMERGENCY_SIGNAL:
 358         case SIGP_SENSE_RUNNING:
 359                 return 0;
 360         /* update counters as we're directly dropping to user space */
 361         case SIGP_STOP:
 362                 vcpu->stat.instruction_sigp_stop++;
 363                 break;
 364         case SIGP_STOP_AND_STORE_STATUS:
 365                 vcpu->stat.instruction_sigp_stop_store_status++;
 366                 break;
 367         case SIGP_STORE_STATUS_AT_ADDRESS:
 368                 vcpu->stat.instruction_sigp_store_status++;
 369                 break;
 370         case SIGP_STORE_ADDITIONAL_STATUS:
 371                 vcpu->stat.instruction_sigp_store_adtl_status++;
 372                 break;
 373         case SIGP_SET_PREFIX:
 374                 vcpu->stat.instruction_sigp_prefix++;
 375                 break;
 376         case SIGP_START:
 377                 vcpu->stat.instruction_sigp_start++;
 378                 break;
 379         case SIGP_RESTART:
 380                 vcpu->stat.instruction_sigp_restart++;
 381                 break;
 382         case SIGP_INITIAL_CPU_RESET:
 383                 vcpu->stat.instruction_sigp_init_cpu_reset++;
 384                 break;
 385         case SIGP_CPU_RESET:
 386                 vcpu->stat.instruction_sigp_cpu_reset++;
 387                 break;
 388         default:
 389                 vcpu->stat.instruction_sigp_unknown++;
 390         }
 391         VCPU_EVENT(vcpu, 3, "SIGP: order %u for CPU %d handled in userspace",
 392                    order_code, cpu_addr);
 393
 394         return 1;
 395 }
 396
 397 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 398 {
 399         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 400         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 401         u32 parameter;
 402         u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 403         u8 order_code;
 404         int rc;
 405
 406         /* sigp in userspace can exit */
 407         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 408                 return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);
 409
 410         order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
 411         if (handle_sigp_order_in_user_space(vcpu, order_code, cpu_addr))
 412                 return -EOPNOTSUPP;
 413
 414         if (r1 % 2)
 415                 parameter = vcpu->run->s.regs.gprs[r1];
 416         else
 417                 parameter = vcpu->run->s.regs.gprs[r1 + 1];
 418
 419         trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
 420         switch (order_code) {
 421         case SIGP_SET_ARCHITECTURE:
 422                 vcpu->stat.instruction_sigp_arch++;
 423                 rc = __sigp_set_arch(vcpu, parameter,
 424                                      &vcpu->run->s.regs.gprs[r1]);
 425                 break;
 426         default:
 427                 rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
 428                                      parameter,
 429                                      &vcpu->run->s.regs.gprs[r1]);
 430         }
 431
 432         if (rc < 0)
 433                 return rc;
 434
 435         kvm_s390_set_psw_cc(vcpu, rc);
 436         return 0;
 437 }
 438
 439 /*
 440  * Handle SIGP partial execution interception.
 441  *
 442  * This interception will occur at the source cpu when a source cpu sends an
 443  * external call to a target cpu and the target cpu has the WAIT bit set in
 444  * its cpuflags. Interception will occurr after the interrupt indicator bits at
 445  * the target cpu have been set. All error cases will lead to instruction
 446  * interception, therefore nothing is to be checked or prepared.
 447  */
 448 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
 449 {
 450         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 451         u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 452         struct kvm_vcpu *dest_vcpu;
 453         u8 order_code = kvm_s390_get_base_disp_rs(vcpu, NULL);
 454
 455         trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);
 456
 457         if (order_code == SIGP_EXTERNAL_CALL) {
 458                 dest_vcpu = kvm_get_vcpu_by_id(vcpu->kvm, cpu_addr);
 459                 BUG_ON(dest_vcpu == NULL);
 460
 461                 kvm_s390_vcpu_wakeup(dest_vcpu);
 462                 kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
 463                 return 0;
 464         }
 465
 466         return -EOPNOTSUPP;
 467 }