linux/arch/s390/kvm/sigp.c
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   1/*
   2 * sigp.c - handlinge interprocessor communication
   3 *
   4 * Copyright IBM Corp. 2008
   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 */
  13
  14#include <linux/kvm.h>
  15#include <linux/kvm_host.h>
  16#include "gaccess.h"
  17#include "kvm-s390.h"
  18
  19/* sigp order codes */
  20#define SIGP_SENSE             0x01
  21#define SIGP_EXTERNAL_CALL     0x02
  22#define SIGP_EMERGENCY         0x03
  23#define SIGP_START             0x04
  24#define SIGP_STOP              0x05
  25#define SIGP_RESTART           0x06
  26#define SIGP_STOP_STORE_STATUS 0x09
  27#define SIGP_INITIAL_CPU_RESET 0x0b
  28#define SIGP_CPU_RESET         0x0c
  29#define SIGP_SET_PREFIX        0x0d
  30#define SIGP_STORE_STATUS_ADDR 0x0e
  31#define SIGP_SET_ARCH          0x12
  32
  33/* cpu status bits */
  34#define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
  35#define SIGP_STAT_INCORRECT_STATE   0x00000200UL
  36#define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
  37#define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
  38#define SIGP_STAT_STOPPED           0x00000040UL
  39#define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
  40#define SIGP_STAT_CHECK_STOP        0x00000010UL
  41#define SIGP_STAT_INOPERATIVE       0x00000004UL
  42#define SIGP_STAT_INVALID_ORDER     0x00000002UL
  43#define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
  44
  45
  46static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
  47                        unsigned long *reg)
  48{
  49        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  50        int rc;
  51
  52        if (cpu_addr >= KVM_MAX_VCPUS)
  53                return 3; /* not operational */
  54
  55        spin_lock_bh(&fi->lock);
  56        if (fi->local_int[cpu_addr] == NULL)
  57                rc = 3; /* not operational */
  58        else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
  59                 & CPUSTAT_RUNNING) {
  60                *reg &= 0xffffffff00000000UL;
  61                rc = 1; /* status stored */
  62        } else {
  63                *reg &= 0xffffffff00000000UL;
  64                *reg |= SIGP_STAT_STOPPED;
  65                rc = 1; /* status stored */
  66        }
  67        spin_unlock_bh(&fi->lock);
  68
  69        VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
  70        return rc;
  71}
  72
  73static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
  74{
  75        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
  76        struct kvm_s390_local_interrupt *li;
  77        struct kvm_s390_interrupt_info *inti;
  78        int rc;
  79
  80        if (cpu_addr >= KVM_MAX_VCPUS)
  81                return 3; /* not operational */
  82
  83        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  84        if (!inti)
  85                return -ENOMEM;
  86
  87        inti->type = KVM_S390_INT_EMERGENCY;
  88
  89        spin_lock_bh(&fi->lock);
  90        li = fi->local_int[cpu_addr];
  91        if (li == NULL) {
  92                rc = 3; /* not operational */
  93                kfree(inti);
  94                goto unlock;
  95        }
  96        spin_lock_bh(&li->lock);
  97        list_add_tail(&inti->list, &li->list);
  98        atomic_set(&li->active, 1);
  99        atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 100        if (waitqueue_active(&li->wq))
 101                wake_up_interruptible(&li->wq);
 102        spin_unlock_bh(&li->lock);
 103        rc = 0; /* order accepted */
 104unlock:
 105        spin_unlock_bh(&fi->lock);
 106        VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
 107        return rc;
 108}
 109
 110static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store)
 111{
 112        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 113        struct kvm_s390_local_interrupt *li;
 114        struct kvm_s390_interrupt_info *inti;
 115        int rc;
 116
 117        if (cpu_addr >= KVM_MAX_VCPUS)
 118                return 3; /* not operational */
 119
 120        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 121        if (!inti)
 122                return -ENOMEM;
 123
 124        inti->type = KVM_S390_SIGP_STOP;
 125
 126        spin_lock_bh(&fi->lock);
 127        li = fi->local_int[cpu_addr];
 128        if (li == NULL) {
 129                rc = 3; /* not operational */
 130                kfree(inti);
 131                goto unlock;
 132        }
 133        spin_lock_bh(&li->lock);
 134        list_add_tail(&inti->list, &li->list);
 135        atomic_set(&li->active, 1);
 136        atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 137        if (store)
 138                li->action_bits |= ACTION_STORE_ON_STOP;
 139        li->action_bits |= ACTION_STOP_ON_STOP;
 140        if (waitqueue_active(&li->wq))
 141                wake_up_interruptible(&li->wq);
 142        spin_unlock_bh(&li->lock);
 143        rc = 0; /* order accepted */
 144unlock:
 145        spin_unlock_bh(&fi->lock);
 146        VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 147        return rc;
 148}
 149
 150static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 151{
 152        int rc;
 153
 154        switch (parameter & 0xff) {
 155        case 0:
 156                printk(KERN_WARNING "kvm: request to switch to ESA/390 mode"
 157                                                        " not supported");
 158                rc = 3; /* not operational */
 159                break;
 160        case 1:
 161        case 2:
 162                rc = 0; /* order accepted */
 163                break;
 164        default:
 165                rc = -ENOTSUPP;
 166        }
 167        return rc;
 168}
 169
 170static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 171                             unsigned long *reg)
 172{
 173        struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 174        struct kvm_s390_local_interrupt *li;
 175        struct kvm_s390_interrupt_info *inti;
 176        int rc;
 177        u8 tmp;
 178
 179        /* make sure that the new value is valid memory */
 180        address = address & 0x7fffe000u;
 181        if ((copy_from_guest(vcpu, &tmp,
 182                (u64) (address + vcpu->kvm->arch.guest_origin) , 1)) ||
 183           (copy_from_guest(vcpu, &tmp, (u64) (address +
 184                        vcpu->kvm->arch.guest_origin + PAGE_SIZE), 1))) {
 185                *reg |= SIGP_STAT_INVALID_PARAMETER;
 186                return 1; /* invalid parameter */
 187        }
 188
 189        inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 190        if (!inti)
 191                return 2; /* busy */
 192
 193        spin_lock_bh(&fi->lock);
 194        li = fi->local_int[cpu_addr];
 195
 196        if ((cpu_addr >= KVM_MAX_VCPUS) || (li == NULL)) {
 197                rc = 1; /* incorrect state */
 198                *reg &= SIGP_STAT_INCORRECT_STATE;
 199                kfree(inti);
 200                goto out_fi;
 201        }
 202
 203        spin_lock_bh(&li->lock);
 204        /* cpu must be in stopped state */
 205        if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
 206                rc = 1; /* incorrect state */
 207                *reg &= SIGP_STAT_INCORRECT_STATE;
 208                kfree(inti);
 209                goto out_li;
 210        }
 211
 212        inti->type = KVM_S390_SIGP_SET_PREFIX;
 213        inti->prefix.address = address;
 214
 215        list_add_tail(&inti->list, &li->list);
 216        atomic_set(&li->active, 1);
 217        if (waitqueue_active(&li->wq))
 218                wake_up_interruptible(&li->wq);
 219        rc = 0; /* order accepted */
 220
 221        VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 222out_li:
 223        spin_unlock_bh(&li->lock);
 224out_fi:
 225        spin_unlock_bh(&fi->lock);
 226        return rc;
 227}
 228
 229int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 230{
 231        int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 232        int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 233        int base2 = vcpu->arch.sie_block->ipb >> 28;
 234        int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 235        u32 parameter;
 236        u16 cpu_addr = vcpu->arch.guest_gprs[r3];
 237        u8 order_code;
 238        int rc;
 239
 240        /* sigp in userspace can exit */
 241        if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 242                return kvm_s390_inject_program_int(vcpu,
 243                                                   PGM_PRIVILEGED_OPERATION);
 244
 245        order_code = disp2;
 246        if (base2)
 247                order_code += vcpu->arch.guest_gprs[base2];
 248
 249        if (r1 % 2)
 250                parameter = vcpu->arch.guest_gprs[r1];
 251        else
 252                parameter = vcpu->arch.guest_gprs[r1 + 1];
 253
 254        switch (order_code) {
 255        case SIGP_SENSE:
 256                vcpu->stat.instruction_sigp_sense++;
 257                rc = __sigp_sense(vcpu, cpu_addr,
 258                                  &vcpu->arch.guest_gprs[r1]);
 259                break;
 260        case SIGP_EMERGENCY:
 261                vcpu->stat.instruction_sigp_emergency++;
 262                rc = __sigp_emergency(vcpu, cpu_addr);
 263                break;
 264        case SIGP_STOP:
 265                vcpu->stat.instruction_sigp_stop++;
 266                rc = __sigp_stop(vcpu, cpu_addr, 0);
 267                break;
 268        case SIGP_STOP_STORE_STATUS:
 269                vcpu->stat.instruction_sigp_stop++;
 270                rc = __sigp_stop(vcpu, cpu_addr, 1);
 271                break;
 272        case SIGP_SET_ARCH:
 273                vcpu->stat.instruction_sigp_arch++;
 274                rc = __sigp_set_arch(vcpu, parameter);
 275                break;
 276        case SIGP_SET_PREFIX:
 277                vcpu->stat.instruction_sigp_prefix++;
 278                rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 279                                       &vcpu->arch.guest_gprs[r1]);
 280                break;
 281        case SIGP_RESTART:
 282                vcpu->stat.instruction_sigp_restart++;
 283                /* user space must know about restart */
 284        default:
 285                return -ENOTSUPP;
 286        }
 287
 288        if (rc < 0)
 289                return rc;
 290
 291        vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 292        vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 293        return 0;
 294}
 295