arch/s390/kvm/sigp.c

   1 /*
   2  * sigp.c - handlinge 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
  22 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
  23                         u64 *reg)
  24 {
  25         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  26         int rc;
  27
  28         if (cpu_addr >= KVM_MAX_VCPUS)
  29                 return 3; /* not operational */
  30
  31         spin_lock(&fi->lock);
  32         if (fi->local_int[cpu_addr] == NULL)
  33                 rc = 3; /* not operational */
  34         else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
  35                   & CPUSTAT_STOPPED)) {
  36                 *reg &= 0xffffffff00000000UL;
  37                 rc = 1; /* status stored */
  38         } else {
  39                 *reg &= 0xffffffff00000000UL;
  40                 *reg |= SIGP_STATUS_STOPPED;
  41                 rc = 1; /* status stored */
  42         }
  43         spin_unlock(&fi->lock);
  44
  45         VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
  46         return rc;
  47 }
  48
  49 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
  50 {
  51         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  52         struct kvm_s390_local_interrupt *li;
  53         struct kvm_s390_interrupt_info *inti;
  54         int rc;
  55
  56         if (cpu_addr >= KVM_MAX_VCPUS)
  57                 return 3; /* not operational */
  58
  59         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  60         if (!inti)
  61                 return -ENOMEM;
  62
  63         inti->type = KVM_S390_INT_EMERGENCY;
  64         inti->emerg.code = vcpu->vcpu_id;
  65
  66         spin_lock(&fi->lock);
  67         li = fi->local_int[cpu_addr];
  68         if (li == NULL) {
  69                 rc = 3; /* not operational */
  70                 kfree(inti);
  71                 goto unlock;
  72         }
  73         spin_lock_bh(&li->lock);
  74         list_add_tail(&inti->list, &li->list);
  75         atomic_set(&li->active, 1);
  76         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
  77         if (waitqueue_active(&li->wq))
  78                 wake_up_interruptible(&li->wq);
  79         spin_unlock_bh(&li->lock);
  80         rc = 0; /* order accepted */
  81         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
  82 unlock:
  83         spin_unlock(&fi->lock);
  84         return rc;
  85 }
  86
  87 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
  88 {
  89         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  90         struct kvm_s390_local_interrupt *li;
  91         struct kvm_s390_interrupt_info *inti;
  92         int rc;
  93
  94         if (cpu_addr >= KVM_MAX_VCPUS)
  95                 return 3; /* not operational */
  96
  97         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  98         if (!inti)
  99                 return -ENOMEM;
 100
 101         inti->type = KVM_S390_INT_EXTERNAL_CALL;
 102         inti->extcall.code = vcpu->vcpu_id;
 103
 104         spin_lock(&fi->lock);
 105         li = fi->local_int[cpu_addr];
 106         if (li == NULL) {
 107                 rc = 3; /* not operational */
 108                 kfree(inti);
 109                 goto unlock;
 110         }
 111         spin_lock_bh(&li->lock);
 112         list_add_tail(&inti->list, &li->list);
 113         atomic_set(&li->active, 1);
 114         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 115         if (waitqueue_active(&li->wq))
 116                 wake_up_interruptible(&li->wq);
 117         spin_unlock_bh(&li->lock);
 118         rc = 0; /* order accepted */
 119         VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
 120 unlock:
 121         spin_unlock(&fi->lock);
 122         return rc;
 123 }
 124
 125 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 126 {
 127         struct kvm_s390_interrupt_info *inti;
 128
 129         inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
 130         if (!inti)
 131                 return -ENOMEM;
 132         inti->type = KVM_S390_SIGP_STOP;
 133
 134         spin_lock_bh(&li->lock);
 135         if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED))
 136                 goto out;
 137         list_add_tail(&inti->list, &li->list);
 138         atomic_set(&li->active, 1);
 139         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 140         li->action_bits |= action;
 141         if (waitqueue_active(&li->wq))
 142                 wake_up_interruptible(&li->wq);
 143 out:
 144         spin_unlock_bh(&li->lock);
 145
 146         return 0; /* order accepted */
 147 }
 148
 149 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 150 {
 151         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 152         struct kvm_s390_local_interrupt *li;
 153         int rc;
 154
 155         if (cpu_addr >= KVM_MAX_VCPUS)
 156                 return 3; /* not operational */
 157
 158         spin_lock(&fi->lock);
 159         li = fi->local_int[cpu_addr];
 160         if (li == NULL) {
 161                 rc = 3; /* not operational */
 162                 goto unlock;
 163         }
 164
 165         rc = __inject_sigp_stop(li, action);
 166
 167 unlock:
 168         spin_unlock(&fi->lock);
 169         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 170         return rc;
 171 }
 172
 173 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 174 {
 175         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 176         return __inject_sigp_stop(li, action);
 177 }
 178
 179 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 180 {
 181         int rc;
 182
 183         switch (parameter & 0xff) {
 184         case 0:
 185                 rc = 3; /* not operational */
 186                 break;
 187         case 1:
 188         case 2:
 189                 rc = 0; /* order accepted */
 190                 break;
 191         default:
 192                 rc = -EOPNOTSUPP;
 193         }
 194         return rc;
 195 }
 196
 197 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 198                              u64 *reg)
 199 {
 200         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 201         struct kvm_s390_local_interrupt *li = NULL;
 202         struct kvm_s390_interrupt_info *inti;
 203         int rc;
 204         u8 tmp;
 205
 206         /* make sure that the new value is valid memory */
 207         address = address & 0x7fffe000u;
 208         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 209            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 210                 *reg |= SIGP_STATUS_INVALID_PARAMETER;
 211                 return 1; /* invalid parameter */
 212         }
 213
 214         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 215         if (!inti)
 216                 return 2; /* busy */
 217
 218         spin_lock(&fi->lock);
 219         if (cpu_addr < KVM_MAX_VCPUS)
 220                 li = fi->local_int[cpu_addr];
 221
 222         if (li == NULL) {
 223                 rc = 1; /* incorrect state */
 224                 *reg &= SIGP_STATUS_INCORRECT_STATE;
 225                 kfree(inti);
 226                 goto out_fi;
 227         }
 228
 229         spin_lock_bh(&li->lock);
 230         /* cpu must be in stopped state */
 231         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 232                 rc = 1; /* incorrect state */
 233                 *reg &= SIGP_STATUS_INCORRECT_STATE;
 234                 kfree(inti);
 235                 goto out_li;
 236         }
 237
 238         inti->type = KVM_S390_SIGP_SET_PREFIX;
 239         inti->prefix.address = address;
 240
 241         list_add_tail(&inti->list, &li->list);
 242         atomic_set(&li->active, 1);
 243         if (waitqueue_active(&li->wq))
 244                 wake_up_interruptible(&li->wq);
 245         rc = 0; /* order accepted */
 246
 247         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 248 out_li:
 249         spin_unlock_bh(&li->lock);
 250 out_fi:
 251         spin_unlock(&fi->lock);
 252         return rc;
 253 }
 254
 255 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 256                                 u64 *reg)
 257 {
 258         int rc;
 259         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 260
 261         if (cpu_addr >= KVM_MAX_VCPUS)
 262                 return 3; /* not operational */
 263
 264         spin_lock(&fi->lock);
 265         if (fi->local_int[cpu_addr] == NULL)
 266                 rc = 3; /* not operational */
 267         else {
 268                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 269                     & CPUSTAT_RUNNING) {
 270                         /* running */
 271                         rc = 1;
 272                 } else {
 273                         /* not running */
 274                         *reg &= 0xffffffff00000000UL;
 275                         *reg |= SIGP_STATUS_NOT_RUNNING;
 276                         rc = 0;
 277                 }
 278         }
 279         spin_unlock(&fi->lock);
 280
 281         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 282                    rc);
 283
 284         return rc;
 285 }
 286
 287 static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
 288 {
 289         int rc = 0;
 290         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 291         struct kvm_s390_local_interrupt *li;
 292
 293         if (cpu_addr >= KVM_MAX_VCPUS)
 294                 return 3; /* not operational */
 295
 296         spin_lock(&fi->lock);
 297         li = fi->local_int[cpu_addr];
 298         if (li == NULL) {
 299                 rc = 3; /* not operational */
 300                 goto out;
 301         }
 302
 303         spin_lock_bh(&li->lock);
 304         if (li->action_bits & ACTION_STOP_ON_STOP)
 305                 rc = 2; /* busy */
 306         else
 307                 VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
 308                         cpu_addr);
 309         spin_unlock_bh(&li->lock);
 310 out:
 311         spin_unlock(&fi->lock);
 312         return rc;
 313 }
 314
 315 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 316 {
 317         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 318         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 319         int base2 = vcpu->arch.sie_block->ipb >> 28;
 320         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 321         u32 parameter;
 322         u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 323         u8 order_code;
 324         int rc;
 325
 326         /* sigp in userspace can exit */
 327         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 328                 return kvm_s390_inject_program_int(vcpu,
 329                                                    PGM_PRIVILEGED_OPERATION);
 330
 331         order_code = disp2;
 332         if (base2)
 333                 order_code += vcpu->run->s.regs.gprs[base2];
 334
 335         if (r1 % 2)
 336                 parameter = vcpu->run->s.regs.gprs[r1];
 337         else
 338                 parameter = vcpu->run->s.regs.gprs[r1 + 1];
 339
 340         switch (order_code) {
 341         case SIGP_SENSE:
 342                 vcpu->stat.instruction_sigp_sense++;
 343                 rc = __sigp_sense(vcpu, cpu_addr,
 344                                   &vcpu->run->s.regs.gprs[r1]);
 345                 break;
 346         case SIGP_EXTERNAL_CALL:
 347                 vcpu->stat.instruction_sigp_external_call++;
 348                 rc = __sigp_external_call(vcpu, cpu_addr);
 349                 break;
 350         case SIGP_EMERGENCY_SIGNAL:
 351                 vcpu->stat.instruction_sigp_emergency++;
 352                 rc = __sigp_emergency(vcpu, cpu_addr);
 353                 break;
 354         case SIGP_STOP:
 355                 vcpu->stat.instruction_sigp_stop++;
 356                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 357                 break;
 358         case SIGP_STOP_AND_STORE_STATUS:
 359                 vcpu->stat.instruction_sigp_stop++;
 360                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 361                                                  ACTION_STOP_ON_STOP);
 362                 break;
 363         case SIGP_SET_ARCHITECTURE:
 364                 vcpu->stat.instruction_sigp_arch++;
 365                 rc = __sigp_set_arch(vcpu, parameter);
 366                 break;
 367         case SIGP_SET_PREFIX:
 368                 vcpu->stat.instruction_sigp_prefix++;
 369                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 370                                        &vcpu->run->s.regs.gprs[r1]);
 371                 break;
 372         case SIGP_SENSE_RUNNING:
 373                 vcpu->stat.instruction_sigp_sense_running++;
 374                 rc = __sigp_sense_running(vcpu, cpu_addr,
 375                                           &vcpu->run->s.regs.gprs[r1]);
 376                 break;
 377         case SIGP_RESTART:
 378                 vcpu->stat.instruction_sigp_restart++;
 379                 rc = __sigp_restart(vcpu, cpu_addr);
 380                 if (rc == 2) /* busy */
 381                         break;
 382                 /* user space must know about restart */
 383         default:
 384                 return -EOPNOTSUPP;
 385         }
 386
 387         if (rc < 0)
 388                 return rc;
 389
 390         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 391         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 392         return 0;
 393 }