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