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 "gaccess.h"
  19 #include "kvm-s390.h"
  20
  21 /* sigp order codes */
  22 #define SIGP_SENSE             0x01
  23 #define SIGP_EXTERNAL_CALL     0x02
  24 #define SIGP_EMERGENCY         0x03
  25 #define SIGP_START             0x04
  26 #define SIGP_STOP              0x05
  27 #define SIGP_RESTART           0x06
  28 #define SIGP_STOP_STORE_STATUS 0x09
  29 #define SIGP_INITIAL_CPU_RESET 0x0b
  30 #define SIGP_CPU_RESET         0x0c
  31 #define SIGP_SET_PREFIX        0x0d
  32 #define SIGP_STORE_STATUS_ADDR 0x0e
  33 #define SIGP_SET_ARCH          0x12
  34 #define SIGP_SENSE_RUNNING     0x15
  35
  36 /* cpu status bits */
  37 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
  38 #define SIGP_STAT_NOT_RUNNING       0x00000400UL
  39 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
  40 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
  41 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
  42 #define SIGP_STAT_STOPPED           0x00000040UL
  43 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
  44 #define SIGP_STAT_CHECK_STOP        0x00000010UL
  45 #define SIGP_STAT_INOPERATIVE       0x00000004UL
  46 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
  47 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
  48
  49
  50 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
  51                         unsigned long *reg)
  52 {
  53         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  54         int rc;
  55
  56         if (cpu_addr >= KVM_MAX_VCPUS)
  57                 return 3; /* not operational */
  58
  59         spin_lock(&fi->lock);
  60         if (fi->local_int[cpu_addr] == NULL)
  61                 rc = 3; /* not operational */
  62         else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
  63                   & CPUSTAT_STOPPED)) {
  64                 *reg &= 0xffffffff00000000UL;
  65                 rc = 1; /* status stored */
  66         } else {
  67                 *reg &= 0xffffffff00000000UL;
  68                 *reg |= SIGP_STAT_STOPPED;
  69                 rc = 1; /* status stored */
  70         }
  71         spin_unlock(&fi->lock);
  72
  73         VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
  74         return rc;
  75 }
  76
  77 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
  78 {
  79         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  80         struct kvm_s390_local_interrupt *li;
  81         struct kvm_s390_interrupt_info *inti;
  82         int rc;
  83
  84         if (cpu_addr >= KVM_MAX_VCPUS)
  85                 return 3; /* not operational */
  86
  87         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  88         if (!inti)
  89                 return -ENOMEM;
  90
  91         inti->type = KVM_S390_INT_EMERGENCY;
  92         inti->emerg.code = vcpu->vcpu_id;
  93
  94         spin_lock(&fi->lock);
  95         li = fi->local_int[cpu_addr];
  96         if (li == NULL) {
  97                 rc = 3; /* not operational */
  98                 kfree(inti);
  99                 goto unlock;
 100         }
 101         spin_lock_bh(&li->lock);
 102         list_add_tail(&inti->list, &li->list);
 103         atomic_set(&li->active, 1);
 104         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 105         if (waitqueue_active(&li->wq))
 106                 wake_up_interruptible(&li->wq);
 107         spin_unlock_bh(&li->lock);
 108         rc = 0; /* order accepted */
 109         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
 110 unlock:
 111         spin_unlock(&fi->lock);
 112         return rc;
 113 }
 114
 115 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
 116 {
 117         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 118         struct kvm_s390_local_interrupt *li;
 119         struct kvm_s390_interrupt_info *inti;
 120         int rc;
 121
 122         if (cpu_addr >= KVM_MAX_VCPUS)
 123                 return 3; /* not operational */
 124
 125         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 126         if (!inti)
 127                 return -ENOMEM;
 128
 129         inti->type = KVM_S390_INT_EXTERNAL_CALL;
 130         inti->extcall.code = vcpu->vcpu_id;
 131
 132         spin_lock(&fi->lock);
 133         li = fi->local_int[cpu_addr];
 134         if (li == NULL) {
 135                 rc = 3; /* not operational */
 136                 kfree(inti);
 137                 goto unlock;
 138         }
 139         spin_lock_bh(&li->lock);
 140         list_add_tail(&inti->list, &li->list);
 141         atomic_set(&li->active, 1);
 142         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 143         if (waitqueue_active(&li->wq))
 144                 wake_up_interruptible(&li->wq);
 145         spin_unlock_bh(&li->lock);
 146         rc = 0; /* order accepted */
 147         VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
 148 unlock:
 149         spin_unlock(&fi->lock);
 150         return rc;
 151 }
 152
 153 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 154 {
 155         struct kvm_s390_interrupt_info *inti;
 156
 157         inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
 158         if (!inti)
 159                 return -ENOMEM;
 160         inti->type = KVM_S390_SIGP_STOP;
 161
 162         spin_lock_bh(&li->lock);
 163         list_add_tail(&inti->list, &li->list);
 164         atomic_set(&li->active, 1);
 165         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 166         li->action_bits |= action;
 167         if (waitqueue_active(&li->wq))
 168                 wake_up_interruptible(&li->wq);
 169         spin_unlock_bh(&li->lock);
 170
 171         return 0; /* order accepted */
 172 }
 173
 174 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 175 {
 176         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 177         struct kvm_s390_local_interrupt *li;
 178         int rc;
 179
 180         if (cpu_addr >= KVM_MAX_VCPUS)
 181                 return 3; /* not operational */
 182
 183         spin_lock(&fi->lock);
 184         li = fi->local_int[cpu_addr];
 185         if (li == NULL) {
 186                 rc = 3; /* not operational */
 187                 goto unlock;
 188         }
 189
 190         rc = __inject_sigp_stop(li, action);
 191
 192 unlock:
 193         spin_unlock(&fi->lock);
 194         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 195         return rc;
 196 }
 197
 198 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 199 {
 200         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 201         return __inject_sigp_stop(li, action);
 202 }
 203
 204 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 205 {
 206         int rc;
 207
 208         switch (parameter & 0xff) {
 209         case 0:
 210                 rc = 3; /* not operational */
 211                 break;
 212         case 1:
 213         case 2:
 214                 rc = 0; /* order accepted */
 215                 break;
 216         default:
 217                 rc = -EOPNOTSUPP;
 218         }
 219         return rc;
 220 }
 221
 222 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 223                              unsigned long *reg)
 224 {
 225         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 226         struct kvm_s390_local_interrupt *li = NULL;
 227         struct kvm_s390_interrupt_info *inti;
 228         int rc;
 229         u8 tmp;
 230
 231         /* make sure that the new value is valid memory */
 232         address = address & 0x7fffe000u;
 233         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 234            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 235                 *reg |= SIGP_STAT_INVALID_PARAMETER;
 236                 return 1; /* invalid parameter */
 237         }
 238
 239         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 240         if (!inti)
 241                 return 2; /* busy */
 242
 243         spin_lock(&fi->lock);
 244         if (cpu_addr < KVM_MAX_VCPUS)
 245                 li = fi->local_int[cpu_addr];
 246
 247         if (li == NULL) {
 248                 rc = 1; /* incorrect state */
 249                 *reg &= SIGP_STAT_INCORRECT_STATE;
 250                 kfree(inti);
 251                 goto out_fi;
 252         }
 253
 254         spin_lock_bh(&li->lock);
 255         /* cpu must be in stopped state */
 256         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 257                 rc = 1; /* incorrect state */
 258                 *reg &= SIGP_STAT_INCORRECT_STATE;
 259                 kfree(inti);
 260                 goto out_li;
 261         }
 262
 263         inti->type = KVM_S390_SIGP_SET_PREFIX;
 264         inti->prefix.address = address;
 265
 266         list_add_tail(&inti->list, &li->list);
 267         atomic_set(&li->active, 1);
 268         if (waitqueue_active(&li->wq))
 269                 wake_up_interruptible(&li->wq);
 270         rc = 0; /* order accepted */
 271
 272         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 273 out_li:
 274         spin_unlock_bh(&li->lock);
 275 out_fi:
 276         spin_unlock(&fi->lock);
 277         return rc;
 278 }
 279
 280 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 281                                 unsigned long *reg)
 282 {
 283         int rc;
 284         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 285
 286         if (cpu_addr >= KVM_MAX_VCPUS)
 287                 return 3; /* not operational */
 288
 289         spin_lock(&fi->lock);
 290         if (fi->local_int[cpu_addr] == NULL)
 291                 rc = 3; /* not operational */
 292         else {
 293                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 294                     & CPUSTAT_RUNNING) {
 295                         /* running */
 296                         rc = 1;
 297                 } else {
 298                         /* not running */
 299                         *reg &= 0xffffffff00000000UL;
 300                         *reg |= SIGP_STAT_NOT_RUNNING;
 301                         rc = 0;
 302                 }
 303         }
 304         spin_unlock(&fi->lock);
 305
 306         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 307                    rc);
 308
 309         return rc;
 310 }
 311
 312 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 313 {
 314         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 315         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 316         int base2 = vcpu->arch.sie_block->ipb >> 28;
 317         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 318         u32 parameter;
 319         u16 cpu_addr = vcpu->arch.guest_gprs[r3];
 320         u8 order_code;
 321         int rc;
 322
 323         /* sigp in userspace can exit */
 324         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 325                 return kvm_s390_inject_program_int(vcpu,
 326                                                    PGM_PRIVILEGED_OPERATION);
 327
 328         order_code = disp2;
 329         if (base2)
 330                 order_code += vcpu->arch.guest_gprs[base2];
 331
 332         if (r1 % 2)
 333                 parameter = vcpu->arch.guest_gprs[r1];
 334         else
 335                 parameter = vcpu->arch.guest_gprs[r1 + 1];
 336
 337         switch (order_code) {
 338         case SIGP_SENSE:
 339                 vcpu->stat.instruction_sigp_sense++;
 340                 rc = __sigp_sense(vcpu, cpu_addr,
 341                                   &vcpu->arch.guest_gprs[r1]);
 342                 break;
 343         case SIGP_EXTERNAL_CALL:
 344                 vcpu->stat.instruction_sigp_external_call++;
 345                 rc = __sigp_external_call(vcpu, cpu_addr);
 346                 break;
 347         case SIGP_EMERGENCY:
 348                 vcpu->stat.instruction_sigp_emergency++;
 349                 rc = __sigp_emergency(vcpu, cpu_addr);
 350                 break;
 351         case SIGP_STOP:
 352                 vcpu->stat.instruction_sigp_stop++;
 353                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 354                 break;
 355         case SIGP_STOP_STORE_STATUS:
 356                 vcpu->stat.instruction_sigp_stop++;
 357                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
 358                 break;
 359         case SIGP_SET_ARCH:
 360                 vcpu->stat.instruction_sigp_arch++;
 361                 rc = __sigp_set_arch(vcpu, parameter);
 362                 break;
 363         case SIGP_SET_PREFIX:
 364                 vcpu->stat.instruction_sigp_prefix++;
 365                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 366                                        &vcpu->arch.guest_gprs[r1]);
 367                 break;
 368         case SIGP_SENSE_RUNNING:
 369                 vcpu->stat.instruction_sigp_sense_running++;
 370                 rc = __sigp_sense_running(vcpu, cpu_addr,
 371                                           &vcpu->arch.guest_gprs[r1]);
 372                 break;
 373         case SIGP_RESTART:
 374                 vcpu->stat.instruction_sigp_restart++;
 375                 /* user space must know about restart */
 376         default:
 377                 return -EOPNOTSUPP;
 378         }
 379
 380         if (rc < 0)
 381                 return rc;
 382
 383         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 384         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 385         return 0;
 386 }