arch/s390/kvm/sigp.c

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