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                 goto out;
 142         list_add_tail(&inti->list, &li->list);
 143         atomic_set(&li->active, 1);
 144         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 145         li->action_bits |= action;
 146         if (waitqueue_active(&li->wq))
 147                 wake_up_interruptible(&li->wq);
 148 out:
 149         spin_unlock_bh(&li->lock);
 150
 151         return SIGP_CC_ORDER_CODE_ACCEPTED;
 152 }
 153
 154 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 155 {
 156         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 157         struct kvm_s390_local_interrupt *li;
 158         int rc;
 159
 160         if (cpu_addr >= KVM_MAX_VCPUS)
 161                 return SIGP_CC_NOT_OPERATIONAL;
 162
 163         spin_lock(&fi->lock);
 164         li = fi->local_int[cpu_addr];
 165         if (li == NULL) {
 166                 rc = SIGP_CC_NOT_OPERATIONAL;
 167                 goto unlock;
 168         }
 169
 170         rc = __inject_sigp_stop(li, action);
 171
 172 unlock:
 173         spin_unlock(&fi->lock);
 174         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 175         return rc;
 176 }
 177
 178 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 179 {
 180         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 181         return __inject_sigp_stop(li, action);
 182 }
 183
 184 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 185 {
 186         int rc;
 187
 188         switch (parameter & 0xff) {
 189         case 0:
 190                 rc = SIGP_CC_NOT_OPERATIONAL;
 191                 break;
 192         case 1:
 193         case 2:
 194                 rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 195                 break;
 196         default:
 197                 rc = -EOPNOTSUPP;
 198         }
 199         return rc;
 200 }
 201
 202 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 203                              u64 *reg)
 204 {
 205         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 206         struct kvm_s390_local_interrupt *li = NULL;
 207         struct kvm_s390_interrupt_info *inti;
 208         int rc;
 209         u8 tmp;
 210
 211         /* make sure that the new value is valid memory */
 212         address = address & 0x7fffe000u;
 213         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 214            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 215                 *reg &= 0xffffffff00000000UL;
 216                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
 217                 return SIGP_CC_STATUS_STORED;
 218         }
 219
 220         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 221         if (!inti)
 222                 return SIGP_CC_BUSY;
 223
 224         spin_lock(&fi->lock);
 225         if (cpu_addr < KVM_MAX_VCPUS)
 226                 li = fi->local_int[cpu_addr];
 227
 228         if (li == NULL) {
 229                 *reg &= 0xffffffff00000000UL;
 230                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 231                 rc = SIGP_CC_STATUS_STORED;
 232                 kfree(inti);
 233                 goto out_fi;
 234         }
 235
 236         spin_lock_bh(&li->lock);
 237         /* cpu must be in stopped state */
 238         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 239                 *reg &= 0xffffffff00000000UL;
 240                 *reg |= SIGP_STATUS_INCORRECT_STATE;
 241                 rc = SIGP_CC_STATUS_STORED;
 242                 kfree(inti);
 243                 goto out_li;
 244         }
 245
 246         inti->type = KVM_S390_SIGP_SET_PREFIX;
 247         inti->prefix.address = address;
 248
 249         list_add_tail(&inti->list, &li->list);
 250         atomic_set(&li->active, 1);
 251         if (waitqueue_active(&li->wq))
 252                 wake_up_interruptible(&li->wq);
 253         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 254
 255         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 256 out_li:
 257         spin_unlock_bh(&li->lock);
 258 out_fi:
 259         spin_unlock(&fi->lock);
 260         return rc;
 261 }
 262
 263 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 264                                 u64 *reg)
 265 {
 266         int rc;
 267         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 268
 269         if (cpu_addr >= KVM_MAX_VCPUS)
 270                 return SIGP_CC_NOT_OPERATIONAL;
 271
 272         spin_lock(&fi->lock);
 273         if (fi->local_int[cpu_addr] == NULL)
 274                 rc = SIGP_CC_NOT_OPERATIONAL;
 275         else {
 276                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 277                     & CPUSTAT_RUNNING) {
 278                         /* running */
 279                         rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 280                 } else {
 281                         /* not running */
 282                         *reg &= 0xffffffff00000000UL;
 283                         *reg |= SIGP_STATUS_NOT_RUNNING;
 284                         rc = SIGP_CC_STATUS_STORED;
 285                 }
 286         }
 287         spin_unlock(&fi->lock);
 288
 289         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 290                    rc);
 291
 292         return rc;
 293 }
 294
 295 static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
 296 {
 297         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 298         struct kvm_s390_local_interrupt *li;
 299         int rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 300
 301         if (cpu_addr >= KVM_MAX_VCPUS)
 302                 return SIGP_CC_NOT_OPERATIONAL;
 303
 304         spin_lock(&fi->lock);
 305         li = fi->local_int[cpu_addr];
 306         if (li == NULL) {
 307                 rc = SIGP_CC_NOT_OPERATIONAL;
 308                 goto out;
 309         }
 310
 311         spin_lock_bh(&li->lock);
 312         if (li->action_bits & ACTION_STOP_ON_STOP)
 313                 rc = SIGP_CC_BUSY;
 314         else
 315                 VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
 316                         cpu_addr);
 317         spin_unlock_bh(&li->lock);
 318 out:
 319         spin_unlock(&fi->lock);
 320         return rc;
 321 }
 322
 323 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 324 {
 325         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 326         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 327         int base2 = vcpu->arch.sie_block->ipb >> 28;
 328         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 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 = disp2;
 340         if (base2)
 341                 order_code += vcpu->run->s.regs.gprs[base2];
 342
 343         if (r1 % 2)
 344                 parameter = vcpu->run->s.regs.gprs[r1];
 345         else
 346                 parameter = vcpu->run->s.regs.gprs[r1 + 1];
 347
 348         trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
 349         switch (order_code) {
 350         case SIGP_SENSE:
 351                 vcpu->stat.instruction_sigp_sense++;
 352                 rc = __sigp_sense(vcpu, cpu_addr,
 353                                   &vcpu->run->s.regs.gprs[r1]);
 354                 break;
 355         case SIGP_EXTERNAL_CALL:
 356                 vcpu->stat.instruction_sigp_external_call++;
 357                 rc = __sigp_external_call(vcpu, cpu_addr);
 358                 break;
 359         case SIGP_EMERGENCY_SIGNAL:
 360                 vcpu->stat.instruction_sigp_emergency++;
 361                 rc = __sigp_emergency(vcpu, cpu_addr);
 362                 break;
 363         case SIGP_STOP:
 364                 vcpu->stat.instruction_sigp_stop++;
 365                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 366                 break;
 367         case SIGP_STOP_AND_STORE_STATUS:
 368                 vcpu->stat.instruction_sigp_stop++;
 369                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 370                                                  ACTION_STOP_ON_STOP);
 371                 break;
 372         case SIGP_SET_ARCHITECTURE:
 373                 vcpu->stat.instruction_sigp_arch++;
 374                 rc = __sigp_set_arch(vcpu, parameter);
 375                 break;
 376         case SIGP_SET_PREFIX:
 377                 vcpu->stat.instruction_sigp_prefix++;
 378                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 379                                        &vcpu->run->s.regs.gprs[r1]);
 380                 break;
 381         case SIGP_SENSE_RUNNING:
 382                 vcpu->stat.instruction_sigp_sense_running++;
 383                 rc = __sigp_sense_running(vcpu, cpu_addr,
 384                                           &vcpu->run->s.regs.gprs[r1]);
 385                 break;
 386         case SIGP_RESTART:
 387                 vcpu->stat.instruction_sigp_restart++;
 388                 rc = __sigp_restart(vcpu, cpu_addr);
 389                 if (rc == SIGP_CC_BUSY)
 390                         break;
 391                 /* user space must know about restart */
 392         default:
 393                 return -EOPNOTSUPP;
 394         }
 395
 396         if (rc < 0)
 397                 return rc;
 398
 399         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 400         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 401         return 0;
 402 }