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                         u64 *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         if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED))
 164                 goto out;
 165         list_add_tail(&inti->list, &li->list);
 166         atomic_set(&li->active, 1);
 167         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 168         li->action_bits |= action;
 169         if (waitqueue_active(&li->wq))
 170                 wake_up_interruptible(&li->wq);
 171 out:
 172         spin_unlock_bh(&li->lock);
 173
 174         return 0; /* order accepted */
 175 }
 176
 177 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 178 {
 179         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 180         struct kvm_s390_local_interrupt *li;
 181         int rc;
 182
 183         if (cpu_addr >= KVM_MAX_VCPUS)
 184                 return 3; /* not operational */
 185
 186         spin_lock(&fi->lock);
 187         li = fi->local_int[cpu_addr];
 188         if (li == NULL) {
 189                 rc = 3; /* not operational */
 190                 goto unlock;
 191         }
 192
 193         rc = __inject_sigp_stop(li, action);
 194
 195 unlock:
 196         spin_unlock(&fi->lock);
 197         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 198         return rc;
 199 }
 200
 201 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 202 {
 203         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 204         return __inject_sigp_stop(li, action);
 205 }
 206
 207 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 208 {
 209         int rc;
 210
 211         switch (parameter & 0xff) {
 212         case 0:
 213                 rc = 3; /* not operational */
 214                 break;
 215         case 1:
 216         case 2:
 217                 rc = 0; /* order accepted */
 218                 break;
 219         default:
 220                 rc = -EOPNOTSUPP;
 221         }
 222         return rc;
 223 }
 224
 225 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 226                              u64 *reg)
 227 {
 228         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 229         struct kvm_s390_local_interrupt *li = NULL;
 230         struct kvm_s390_interrupt_info *inti;
 231         int rc;
 232         u8 tmp;
 233
 234         /* make sure that the new value is valid memory */
 235         address = address & 0x7fffe000u;
 236         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 237            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 238                 *reg |= SIGP_STAT_INVALID_PARAMETER;
 239                 return 1; /* invalid parameter */
 240         }
 241
 242         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 243         if (!inti)
 244                 return 2; /* busy */
 245
 246         spin_lock(&fi->lock);
 247         if (cpu_addr < KVM_MAX_VCPUS)
 248                 li = fi->local_int[cpu_addr];
 249
 250         if (li == NULL) {
 251                 rc = 1; /* incorrect state */
 252                 *reg &= SIGP_STAT_INCORRECT_STATE;
 253                 kfree(inti);
 254                 goto out_fi;
 255         }
 256
 257         spin_lock_bh(&li->lock);
 258         /* cpu must be in stopped state */
 259         if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 260                 rc = 1; /* incorrect state */
 261                 *reg &= SIGP_STAT_INCORRECT_STATE;
 262                 kfree(inti);
 263                 goto out_li;
 264         }
 265
 266         inti->type = KVM_S390_SIGP_SET_PREFIX;
 267         inti->prefix.address = address;
 268
 269         list_add_tail(&inti->list, &li->list);
 270         atomic_set(&li->active, 1);
 271         if (waitqueue_active(&li->wq))
 272                 wake_up_interruptible(&li->wq);
 273         rc = 0; /* order accepted */
 274
 275         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 276 out_li:
 277         spin_unlock_bh(&li->lock);
 278 out_fi:
 279         spin_unlock(&fi->lock);
 280         return rc;
 281 }
 282
 283 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 284                                 u64 *reg)
 285 {
 286         int rc;
 287         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 288
 289         if (cpu_addr >= KVM_MAX_VCPUS)
 290                 return 3; /* not operational */
 291
 292         spin_lock(&fi->lock);
 293         if (fi->local_int[cpu_addr] == NULL)
 294                 rc = 3; /* not operational */
 295         else {
 296                 if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 297                     & CPUSTAT_RUNNING) {
 298                         /* running */
 299                         rc = 1;
 300                 } else {
 301                         /* not running */
 302                         *reg &= 0xffffffff00000000UL;
 303                         *reg |= SIGP_STAT_NOT_RUNNING;
 304                         rc = 0;
 305                 }
 306         }
 307         spin_unlock(&fi->lock);
 308
 309         VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 310                    rc);
 311
 312         return rc;
 313 }
 314
 315 static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
 316 {
 317         int rc = 0;
 318         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 319         struct kvm_s390_local_interrupt *li;
 320
 321         if (cpu_addr >= KVM_MAX_VCPUS)
 322                 return 3; /* not operational */
 323
 324         spin_lock(&fi->lock);
 325         li = fi->local_int[cpu_addr];
 326         if (li == NULL) {
 327                 rc = 3; /* not operational */
 328                 goto out;
 329         }
 330
 331         spin_lock_bh(&li->lock);
 332         if (li->action_bits & ACTION_STOP_ON_STOP)
 333                 rc = 2; /* busy */
 334         else
 335                 VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
 336                         cpu_addr);
 337         spin_unlock_bh(&li->lock);
 338 out:
 339         spin_unlock(&fi->lock);
 340         return rc;
 341 }
 342
 343 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 344 {
 345         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 346         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 347         int base2 = vcpu->arch.sie_block->ipb >> 28;
 348         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 349         u32 parameter;
 350         u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 351         u8 order_code;
 352         int rc;
 353
 354         /* sigp in userspace can exit */
 355         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 356                 return kvm_s390_inject_program_int(vcpu,
 357                                                    PGM_PRIVILEGED_OPERATION);
 358
 359         order_code = disp2;
 360         if (base2)
 361                 order_code += vcpu->run->s.regs.gprs[base2];
 362
 363         if (r1 % 2)
 364                 parameter = vcpu->run->s.regs.gprs[r1];
 365         else
 366                 parameter = vcpu->run->s.regs.gprs[r1 + 1];
 367
 368         switch (order_code) {
 369         case SIGP_SENSE:
 370                 vcpu->stat.instruction_sigp_sense++;
 371                 rc = __sigp_sense(vcpu, cpu_addr,
 372                                   &vcpu->run->s.regs.gprs[r1]);
 373                 break;
 374         case SIGP_EXTERNAL_CALL:
 375                 vcpu->stat.instruction_sigp_external_call++;
 376                 rc = __sigp_external_call(vcpu, cpu_addr);
 377                 break;
 378         case SIGP_EMERGENCY:
 379                 vcpu->stat.instruction_sigp_emergency++;
 380                 rc = __sigp_emergency(vcpu, cpu_addr);
 381                 break;
 382         case SIGP_STOP:
 383                 vcpu->stat.instruction_sigp_stop++;
 384                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 385                 break;
 386         case SIGP_STOP_STORE_STATUS:
 387                 vcpu->stat.instruction_sigp_stop++;
 388                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 389                                                  ACTION_STOP_ON_STOP);
 390                 break;
 391         case SIGP_SET_ARCH:
 392                 vcpu->stat.instruction_sigp_arch++;
 393                 rc = __sigp_set_arch(vcpu, parameter);
 394                 break;
 395         case SIGP_SET_PREFIX:
 396                 vcpu->stat.instruction_sigp_prefix++;
 397                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 398                                        &vcpu->run->s.regs.gprs[r1]);
 399                 break;
 400         case SIGP_SENSE_RUNNING:
 401                 vcpu->stat.instruction_sigp_sense_running++;
 402                 rc = __sigp_sense_running(vcpu, cpu_addr,
 403                                           &vcpu->run->s.regs.gprs[r1]);
 404                 break;
 405         case SIGP_RESTART:
 406                 vcpu->stat.instruction_sigp_restart++;
 407                 rc = __sigp_restart(vcpu, cpu_addr);
 408                 if (rc == 2) /* busy */
 409                         break;
 410                 /* user space must know about restart */
 411         default:
 412                 return -EOPNOTSUPP;
 413         }
 414
 415         if (rc < 0)
 416                 return rc;
 417
 418         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 419         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 420         return 0;
 421 }