arch/s390/kvm/sigp.c

   1 /*
   2  * handling interprocessor communication
   3  *
   4  * Copyright IBM Corp. 2008, 2009
   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  *               Christian Ehrhardt <ehrhardt@de.ibm.com>
  13  */
  14
  15 #include <linux/kvm.h>
  16 #include <linux/kvm_host.h>
  17 #include <linux/slab.h>
  18 #include <asm/sigp.h>
  19 #include "gaccess.h"
  20 #include "kvm-s390.h"
  21 #include "trace.h"
  22
  23 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
  24                         u64 *reg)
  25 {
  26         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  27         int rc;
  28
  29         if (cpu_addr >= KVM_MAX_VCPUS)
  30                 return SIGP_CC_NOT_OPERATIONAL;
  31
  32         spin_lock(&fi->lock);
  33         if (fi->local_int[cpu_addr] == NULL)
  34                 rc = SIGP_CC_NOT_OPERATIONAL;
  35         else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
  36                    & (CPUSTAT_ECALL_PEND | CPUSTAT_STOPPED)))
  37                 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
  38         else {
  39                 *reg &= 0xffffffff00000000UL;
  40                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
  41                     & CPUSTAT_ECALL_PEND)
  42                         *reg |= SIGP_STATUS_EXT_CALL_PENDING;
  43                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
  44                     & CPUSTAT_STOPPED)
  45                         *reg |= SIGP_STATUS_STOPPED;
  46                 rc = SIGP_CC_STATUS_STORED;
  47         }
  48         spin_unlock(&fi->lock);
  49
  50         VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
  51         return rc;
  52 }
  53
  54 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
  55 {
  56         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  57         struct kvm_s390_local_interrupt *li;
  58         struct kvm_s390_interrupt_info *inti;
  59         int rc;
  60
  61         if (cpu_addr >= KVM_MAX_VCPUS)
  62                 return SIGP_CC_NOT_OPERATIONAL;
  63
  64         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  65         if (!inti)
  66                 return -ENOMEM;
  67
  68         inti->type = KVM_S390_INT_EMERGENCY;
  69         inti->emerg.code = vcpu->vcpu_id;
  70
  71         spin_lock(&fi->lock);
  72         li = fi->local_int[cpu_addr];
  73         if (li == NULL) {
  74                 rc = SIGP_CC_NOT_OPERATIONAL;
  75                 kfree(inti);
  76                 goto unlock;
  77         }
  78         spin_lock_bh(&li->lock);
  79         list_add_tail(&inti->list, &li->list);
  80         atomic_set(&li->active, 1);
  81         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
  82         if (waitqueue_active(&li->wq))
  83                 wake_up_interruptible(&li->wq);
  84         spin_unlock_bh(&li->lock);
  85         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
  86         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
  87 unlock:
  88         spin_unlock(&fi->lock);
  89         return rc;
  90 }
  91
  92 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
  93 {
  94         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  95         struct kvm_s390_local_interrupt *li;
  96         struct kvm_s390_interrupt_info *inti;
  97         int rc;
  98
  99         if (cpu_addr >= KVM_MAX_VCPUS)
 100                 return SIGP_CC_NOT_OPERATIONAL;
 101
 102         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 103         if (!inti)
 104                 return -ENOMEM;
 105
 106         inti->type = KVM_S390_INT_EXTERNAL_CALL;
 107         inti->extcall.code = vcpu->vcpu_id;
 108
 109         spin_lock(&fi->lock);
 110         li = fi->local_int[cpu_addr];
 111         if (li == NULL) {
 112                 rc = SIGP_CC_NOT_OPERATIONAL;
 113                 kfree(inti);
 114                 goto unlock;
 115         }
 116         spin_lock_bh(&li->lock);
 117         list_add_tail(&inti->list, &li->list);
 118         atomic_set(&li->active, 1);
 119         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 120         if (waitqueue_active(&li->wq))
 121                 wake_up_interruptible(&li->wq);
 122         spin_unlock_bh(&li->lock);
 123         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 124         VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
 125 unlock:
 126         spin_unlock(&fi->lock);
 127         return rc;
 128 }
 129
 130 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 131 {
 132         struct kvm_s390_interrupt_info *inti;
 133
 134         inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
 135         if (!inti)
 136                 return -ENOMEM;
 137         inti->type = KVM_S390_SIGP_STOP;
 138
 139         spin_lock_bh(&li->lock);
 140         if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 141                 kfree(inti);
 142                 goto out;
 143         }
 144         list_add_tail(&inti->list, &li->list);
 145         atomic_set(&li->active, 1);
 146         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 147         li->action_bits |= action;
 148         if (waitqueue_active(&li->wq))
 149                 wake_up_interruptible(&li->wq);
 150 out:
 151         spin_unlock_bh(&li->lock);
 152
 153         return SIGP_CC_ORDER_CODE_ACCEPTED;
 154 }
 155
 156 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 157 {
 158         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 159         struct kvm_s390_local_interrupt *li;
 160         int rc;
 161
 162         if (cpu_addr >= KVM_MAX_VCPUS)
 163                 return SIGP_CC_NOT_OPERATIONAL;
 164
 165         spin_lock(&fi->lock);
 166         li = fi->local_int[cpu_addr];
 167         if (li == NULL) {
 168                 rc = SIGP_CC_NOT_OPERATIONAL;
 169                 goto unlock;
 170         }
 171
 172         rc = __inject_sigp_stop(li, action);
 173
 174 unlock:
 175         spin_unlock(&fi->lock);
 176         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 177         return rc;
 178 }
 179
 180 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 181 {
 182         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 183         return __inject_sigp_stop(li, action);
 184 }
 185
 186 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 187 {
 188         int rc;
 189
 190         switch (parameter & 0xff) {
 191         case 0:
 192                 rc = SIGP_CC_NOT_OPERATIONAL;
 193                 break;
 194         case 1:
 195         case 2:
 196                 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 197                 break;
 198         default:
 199                 rc = -EOPNOTSUPP;
 200         }
 201         return rc;
 202 }
 203
 204 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 205                              u64 *reg)
 206 {
 207         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 208         struct kvm_s390_local_interrupt *li = NULL;
 209         struct kvm_s390_interrupt_info *inti;
 210         int rc;
 211         u8 tmp;
 212
 213         /* make sure that the new value is valid memory */
 214         address = address & 0x7fffe000u;
 215         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 216            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 217                 *reg &= 0xffffffff00000000UL;
 218                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
 219                 return SIGP_CC_STATUS_STORED;
 220         }
 221
 222         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 223         if (!inti)
 224                 return SIGP_CC_BUSY;
 225
 226         spin_lock(&fi->lock);
 227         if (cpu_addr < KVM_MAX_VCPUS)
 228                 li = fi->local_int[cpu_addr];
 229
 230         if (li == NULL) {
 231                 *reg &= 0xffffffff00000000UL;
 232                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 233                 rc = SIGP_CC_STATUS_STORED;
 234                 kfree(inti);
 235                 goto out_fi;
 236         }
 237
 238         spin_lock_bh(&li->lock);
 239         /* cpu must be in stopped state */
 240         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 241                 *reg &= 0xffffffff00000000UL;
 242                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 243                 rc = SIGP_CC_STATUS_STORED;
 244                 kfree(inti);
 245                 goto out_li;
 246         }
 247
 248         inti->type = KVM_S390_SIGP_SET_PREFIX;
 249         inti->prefix.address = address;
 250
 251         list_add_tail(&inti->list, &li->list);
 252         atomic_set(&li->active, 1);
 253         if (waitqueue_active(&li->wq))
 254                 wake_up_interruptible(&li->wq);
 255         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 256
 257         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 258 out_li:
 259         spin_unlock_bh(&li->lock);
 260 out_fi:
 261         spin_unlock(&fi->lock);
 262         return rc;
 263 }
 264
 265 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 266                                 u64 *reg)
 267 {
 268         int rc;
 269         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 270
 271         if (cpu_addr >= KVM_MAX_VCPUS)
 272                 return SIGP_CC_NOT_OPERATIONAL;
 273
 274         spin_lock(&fi->lock);
 275         if (fi->local_int[cpu_addr] == NULL)
 276                 rc = SIGP_CC_NOT_OPERATIONAL;
 277         else {
 278                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 279                     & CPUSTAT_RUNNING) {
 280                         /* running */
 281                         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 282                 } else {
 283                         /* not running */
 284                         *reg &= 0xffffffff00000000UL;
 285                         *reg |= SIGP_STATUS_NOT_RUNNING;
 286                         rc = SIGP_CC_STATUS_STORED;
 287                 }
 288         }
 289         spin_unlock(&fi->lock);
 290
 291         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 292                    rc);
 293
 294         return rc;
 295 }
 296
 297 static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
 298 {
 299         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 300         struct kvm_s390_local_interrupt *li;
 301         int rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 302
 303         if (cpu_addr >= KVM_MAX_VCPUS)
 304                 return SIGP_CC_NOT_OPERATIONAL;
 305
 306         spin_lock(&fi->lock);
 307         li = fi->local_int[cpu_addr];
 308         if (li == NULL) {
 309                 rc = SIGP_CC_NOT_OPERATIONAL;
 310                 goto out;
 311         }
 312
 313         spin_lock_bh(&li->lock);
 314         if (li->action_bits & ACTION_STOP_ON_STOP)
 315                 rc = SIGP_CC_BUSY;
 316         else
 317                 VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
 318                         cpu_addr);
 319         spin_unlock_bh(&li->lock);
 320 out:
 321         spin_unlock(&fi->lock);
 322         return rc;
 323 }
 324
 325 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 326 {
 327         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 328         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 329         u32 parameter;
 330         u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 331         u8 order_code;
 332         int rc;
 333
 334         /* sigp in userspace can exit */
 335         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 336                 return kvm_s390_inject_program_int(vcpu,
 337                                                    PGM_PRIVILEGED_OPERATION);
 338
 339         order_code = kvm_s390_get_base_disp_rs(vcpu);
 340
 341         if (r1 % 2)
 342                 parameter = vcpu->run->s.regs.gprs[r1];
 343         else
 344                 parameter = vcpu->run->s.regs.gprs[r1 + 1];
 345
 346         trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
 347         switch (order_code) {
 348         case SIGP_SENSE:
 349                 vcpu->stat.instruction_sigp_sense++;
 350                 rc = __sigp_sense(vcpu, cpu_addr,
 351                                   &vcpu->run->s.regs.gprs[r1]);
 352                 break;
 353         case SIGP_EXTERNAL_CALL:
 354                 vcpu->stat.instruction_sigp_external_call++;
 355                 rc = __sigp_external_call(vcpu, cpu_addr);
 356                 break;
 357         case SIGP_EMERGENCY_SIGNAL:
 358                 vcpu->stat.instruction_sigp_emergency++;
 359                 rc = __sigp_emergency(vcpu, cpu_addr);
 360                 break;
 361         case SIGP_STOP:
 362                 vcpu->stat.instruction_sigp_stop++;
 363                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 364                 break;
 365         case SIGP_STOP_AND_STORE_STATUS:
 366                 vcpu->stat.instruction_sigp_stop++;
 367                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 368                                                  ACTION_STOP_ON_STOP);
 369                 break;
 370         case SIGP_SET_ARCHITECTURE:
 371                 vcpu->stat.instruction_sigp_arch++;
 372                 rc = __sigp_set_arch(vcpu, parameter);
 373                 break;
 374         case SIGP_SET_PREFIX:
 375                 vcpu->stat.instruction_sigp_prefix++;
 376                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 377                                        &vcpu->run->s.regs.gprs[r1]);
 378                 break;
 379         case SIGP_SENSE_RUNNING:
 380                 vcpu->stat.instruction_sigp_sense_running++;
 381                 rc = __sigp_sense_running(vcpu, cpu_addr,
 382                                           &vcpu->run->s.regs.gprs[r1]);
 383                 break;
 384         case SIGP_RESTART:
 385                 vcpu->stat.instruction_sigp_restart++;
 386                 rc = __sigp_restart(vcpu, cpu_addr);
 387                 if (rc == SIGP_CC_BUSY)
 388                         break;
 389                 /* user space must know about restart */
 390         default:
 391                 return -EOPNOTSUPP;
 392         }
 393
 394         if (rc < 0)
 395                 return rc;
 396
 397         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 398         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 399         return 0;
 400 }