arch/arm/kvm/guest.c

   1 /*
   2  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   3  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License, version 2, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  */
  18
  19 #include <linux/errno.h>
  20 #include <linux/err.h>
  21 #include <linux/kvm_host.h>
  22 #include <linux/module.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/fs.h>
  25 #include <asm/cputype.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/kvm.h>
  28 #include <asm/kvm_asm.h>
  29 #include <asm/kvm_emulate.h>
  30 #include <asm/kvm_coproc.h>
  31
  32 #define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
  33 #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
  34
  35 struct kvm_stats_debugfs_item debugfs_entries[] = {
  36         { NULL }
  37 };
  38
  39 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  40 {
  41         return 0;
  42 }
  43
  44 static u64 core_reg_offset_from_id(u64 id)
  45 {
  46         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  47 }
  48
  49 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  50 {
  51         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  52         struct kvm_regs *regs = &vcpu->arch.regs;
  53         u64 off;
  54
  55         if (KVM_REG_SIZE(reg->id) != 4)
  56                 return -ENOENT;
  57
  58         /* Our ID is an index into the kvm_regs struct. */
  59         off = core_reg_offset_from_id(reg->id);
  60         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  61                 return -ENOENT;
  62
  63         return put_user(((u32 *)regs)[off], uaddr);
  64 }
  65
  66 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  67 {
  68         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  69         struct kvm_regs *regs = &vcpu->arch.regs;
  70         u64 off, val;
  71
  72         if (KVM_REG_SIZE(reg->id) != 4)
  73                 return -ENOENT;
  74
  75         /* Our ID is an index into the kvm_regs struct. */
  76         off = core_reg_offset_from_id(reg->id);
  77         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  78                 return -ENOENT;
  79
  80         if (get_user(val, uaddr) != 0)
  81                 return -EFAULT;
  82
  83         if (off == KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr)) {
  84                 unsigned long mode = val & MODE_MASK;
  85                 switch (mode) {
  86                 case USR_MODE:
  87                 case FIQ_MODE:
  88                 case IRQ_MODE:
  89                 case SVC_MODE:
  90                 case ABT_MODE:
  91                 case UND_MODE:
  92                         break;
  93                 default:
  94                         return -EINVAL;
  95                 }
  96         }
  97
  98         ((u32 *)regs)[off] = val;
  99         return 0;
 100 }
 101
 102 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 103 {
 104         return -EINVAL;
 105 }
 106
 107 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 108 {
 109         return -EINVAL;
 110 }
 111
 112 #define NUM_TIMER_REGS 3
 113
 114 static bool is_timer_reg(u64 index)
 115 {
 116         switch (index) {
 117         case KVM_REG_ARM_TIMER_CTL:
 118         case KVM_REG_ARM_TIMER_CNT:
 119         case KVM_REG_ARM_TIMER_CVAL:
 120                 return true;
 121         }
 122         return false;
 123 }
 124
 125 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 126 {
 127         if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 128                 return -EFAULT;
 129         uindices++;
 130         if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 131                 return -EFAULT;
 132         uindices++;
 133         if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 134                 return -EFAULT;
 135
 136         return 0;
 137 }
 138
 139 static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 140 {
 141         void __user *uaddr = (void __user *)(long)reg->addr;
 142         u64 val;
 143         int ret;
 144
 145         ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 146         if (ret != 0)
 147                 return -EFAULT;
 148
 149         return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 150 }
 151
 152 static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 153 {
 154         void __user *uaddr = (void __user *)(long)reg->addr;
 155         u64 val;
 156
 157         val = kvm_arm_timer_get_reg(vcpu, reg->id);
 158         return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id));
 159 }
 160
 161 static unsigned long num_core_regs(void)
 162 {
 163         return sizeof(struct kvm_regs) / sizeof(u32);
 164 }
 165
 166 /**
 167  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 168  *
 169  * This is for all registers.
 170  */
 171 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 172 {
 173         return num_core_regs() + kvm_arm_num_coproc_regs(vcpu)
 174                 + NUM_TIMER_REGS;
 175 }
 176
 177 /**
 178  * kvm_arm_copy_reg_indices - get indices of all registers.
 179  *
 180  * We do core registers right here, then we apppend coproc regs.
 181  */
 182 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 183 {
 184         unsigned int i;
 185         const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
 186         int ret;
 187
 188         for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
 189                 if (put_user(core_reg | i, uindices))
 190                         return -EFAULT;
 191                 uindices++;
 192         }
 193
 194         ret = copy_timer_indices(vcpu, uindices);
 195         if (ret)
 196                 return ret;
 197         uindices += NUM_TIMER_REGS;
 198
 199         return kvm_arm_copy_coproc_indices(vcpu, uindices);
 200 }
 201
 202 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 203 {
 204         /* We currently use nothing arch-specific in upper 32 bits */
 205         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 206                 return -EINVAL;
 207
 208         /* Register group 16 means we want a core register. */
 209         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 210                 return get_core_reg(vcpu, reg);
 211
 212         if (is_timer_reg(reg->id))
 213                 return get_timer_reg(vcpu, reg);
 214
 215         return kvm_arm_coproc_get_reg(vcpu, reg);
 216 }
 217
 218 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 219 {
 220         /* We currently use nothing arch-specific in upper 32 bits */
 221         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 222                 return -EINVAL;
 223
 224         /* Register group 16 means we set a core register. */
 225         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 226                 return set_core_reg(vcpu, reg);
 227
 228         if (is_timer_reg(reg->id))
 229                 return set_timer_reg(vcpu, reg);
 230
 231         return kvm_arm_coproc_set_reg(vcpu, reg);
 232 }
 233
 234 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 235                                   struct kvm_sregs *sregs)
 236 {
 237         return -EINVAL;
 238 }
 239
 240 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 241                                   struct kvm_sregs *sregs)
 242 {
 243         return -EINVAL;
 244 }
 245
 246 int __attribute_const__ kvm_target_cpu(void)
 247 {
 248         switch (read_cpuid_part()) {
 249         case ARM_CPU_PART_CORTEX_A7:
 250                 return KVM_ARM_TARGET_CORTEX_A7;
 251         case ARM_CPU_PART_CORTEX_A15:
 252                 return KVM_ARM_TARGET_CORTEX_A15;
 253         default:
 254                 return -EINVAL;
 255         }
 256 }
 257
 258 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 259 {
 260         int target = kvm_target_cpu();
 261
 262         if (target < 0)
 263                 return -ENODEV;
 264
 265         memset(init, 0, sizeof(*init));
 266
 267         /*
 268          * For now, we don't return any features.
 269          * In future, we might use features to return target
 270          * specific features available for the preferred
 271          * target type.
 272          */
 273         init->target = (__u32)target;
 274
 275         return 0;
 276 }
 277
 278 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 279 {
 280         return -EINVAL;
 281 }
 282
 283 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 284 {
 285         return -EINVAL;
 286 }
 287
 288 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 289                                   struct kvm_translation *tr)
 290 {
 291         return -EINVAL;
 292 }