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
  91         spin_lock(&fi->lock);
  92         li = fi->local_int[cpu_addr];
  93         if (li == NULL) {
  94                 rc = 3; /* not operational */
  95                 kfree(inti);
  96                 goto unlock;
  97         }
  98         spin_lock_bh(&li->lock);
  99         list_add_tail(&inti->list, &li->list);
 100         atomic_set(&li->active, 1);
 101         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 102         if (waitqueue_active(&li->wq))
 103                 wake_up_interruptible(&li->wq);
 104         spin_unlock_bh(&li->lock);
 105         rc = 0; /* order accepted */
 106 unlock:
 107         spin_unlock(&fi->lock);
 108         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
 109         return rc;
 110 }
 111
 112 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 113 {
 114         struct kvm_s390_interrupt_info *inti;
 115
 116         inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
 117         if (!inti)
 118                 return -ENOMEM;
 119         inti->type = KVM_S390_SIGP_STOP;
 120
 121         spin_lock_bh(&li->lock);
 122         list_add_tail(&inti->list, &li->list);
 123         atomic_set(&li->active, 1);
 124         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 125         li->action_bits |= action;
 126         if (waitqueue_active(&li->wq))
 127                 wake_up_interruptible(&li->wq);
 128         spin_unlock_bh(&li->lock);
 129
 130         return 0; /* order accepted */
 131 }
 132
 133 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 134 {
 135         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 136         struct kvm_s390_local_interrupt *li;
 137         int rc;
 138
 139         if (cpu_addr >= KVM_MAX_VCPUS)
 140                 return 3; /* not operational */
 141
 142         spin_lock(&fi->lock);
 143         li = fi->local_int[cpu_addr];
 144         if (li == NULL) {
 145                 rc = 3; /* not operational */
 146                 goto unlock;
 147         }
 148
 149         rc = __inject_sigp_stop(li, action);
 150
 151 unlock:
 152         spin_unlock(&fi->lock);
 153         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 154         return rc;
 155 }
 156
 157 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 158 {
 159         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 160         return __inject_sigp_stop(li, action);
 161 }
 162
 163 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 164 {
 165         int rc;
 166
 167         switch (parameter & 0xff) {
 168         case 0:
 169                 rc = 3; /* not operational */
 170                 break;
 171         case 1:
 172         case 2:
 173                 rc = 0; /* order accepted */
 174                 break;
 175         default:
 176                 rc = -EOPNOTSUPP;
 177         }
 178         return rc;
 179 }
 180
 181 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 182                              unsigned long *reg)
 183 {
 184         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 185         struct kvm_s390_local_interrupt *li = NULL;
 186         struct kvm_s390_interrupt_info *inti;
 187         int rc;
 188         u8 tmp;
 189
 190         /* make sure that the new value is valid memory */
 191         address = address & 0x7fffe000u;
 192         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 193            copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 194                 *reg |= SIGP_STAT_INVALID_PARAMETER;
 195                 return 1; /* invalid parameter */
 196         }
 197
 198         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 199         if (!inti)
 200                 return 2; /* busy */
 201
 202         spin_lock(&fi->lock);
 203         if (cpu_addr < KVM_MAX_VCPUS)
 204                 li = fi->local_int[cpu_addr];
 205
 206         if (li == NULL) {
 207                 rc = 1; /* incorrect state */
 208                 *reg &= SIGP_STAT_INCORRECT_STATE;
 209                 kfree(inti);
 210                 goto out_fi;
 211         }
 212
 213         spin_lock_bh(&li->lock);
 214         /* cpu must be in stopped state */
 215         if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
 216                 rc = 1; /* incorrect state */
 217                 *reg &= SIGP_STAT_INCORRECT_STATE;
 218                 kfree(inti);
 219                 goto out_li;
 220         }
 221
 222         inti->type = KVM_S390_SIGP_SET_PREFIX;
 223         inti->prefix.address = address;
 224
 225         list_add_tail(&inti->list, &li->list);
 226         atomic_set(&li->active, 1);
 227         if (waitqueue_active(&li->wq))
 228                 wake_up_interruptible(&li->wq);
 229         rc = 0; /* order accepted */
 230
 231         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 232 out_li:
 233         spin_unlock_bh(&li->lock);
 234 out_fi:
 235         spin_unlock(&fi->lock);
 236         return rc;
 237 }
 238
 239 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 240 {
 241         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 242         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 243         int base2 = vcpu->arch.sie_block->ipb >> 28;
 244         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 245         u32 parameter;
 246         u16 cpu_addr = vcpu->arch.guest_gprs[r3];
 247         u8 order_code;
 248         int rc;
 249
 250         /* sigp in userspace can exit */
 251         if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 252                 return kvm_s390_inject_program_int(vcpu,
 253                                                    PGM_PRIVILEGED_OPERATION);
 254
 255         order_code = disp2;
 256         if (base2)
 257                 order_code += vcpu->arch.guest_gprs[base2];
 258
 259         if (r1 % 2)
 260                 parameter = vcpu->arch.guest_gprs[r1];
 261         else
 262                 parameter = vcpu->arch.guest_gprs[r1 + 1];
 263
 264         switch (order_code) {
 265         case SIGP_SENSE:
 266                 vcpu->stat.instruction_sigp_sense++;
 267                 rc = __sigp_sense(vcpu, cpu_addr,
 268                                   &vcpu->arch.guest_gprs[r1]);
 269                 break;
 270         case SIGP_EMERGENCY:
 271                 vcpu->stat.instruction_sigp_emergency++;
 272                 rc = __sigp_emergency(vcpu, cpu_addr);
 273                 break;
 274         case SIGP_STOP:
 275                 vcpu->stat.instruction_sigp_stop++;
 276                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 277                 break;
 278         case SIGP_STOP_STORE_STATUS:
 279                 vcpu->stat.instruction_sigp_stop++;
 280                 rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
 281                 break;
 282         case SIGP_SET_ARCH:
 283                 vcpu->stat.instruction_sigp_arch++;
 284                 rc = __sigp_set_arch(vcpu, parameter);
 285                 break;
 286         case SIGP_SET_PREFIX:
 287                 vcpu->stat.instruction_sigp_prefix++;
 288                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 289                                        &vcpu->arch.guest_gprs[r1]);
 290                 break;
 291         case SIGP_RESTART:
 292                 vcpu->stat.instruction_sigp_restart++;
 293                 /* user space must know about restart */
 294         default:
 295                 return -EOPNOTSUPP;
 296         }
 297
 298         if (rc < 0)
 299                 return rc;
 300
 301         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 302         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 303         return 0;
 304 }