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