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,
  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
  73 static 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 */
 104 unlock:
 105         spin_unlock_bh(&fi->lock);
 106         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
 107         return rc;
 108 }
 109
 110 static 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 */
 144 unlock:
 145         spin_unlock_bh(&fi->lock);
 146         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 147         return rc;
 148 }
 149
 150 static 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
 170 static 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);
 222 out_li:
 223         spin_unlock_bh(&li->lock);
 224 out_fi:
 225         spin_unlock_bh(&fi->lock);
 226         return rc;
 227 }
 228
 229 int 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 }