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 static unsigned long num_core_regs(void)
 113 {
 114         return sizeof(struct kvm_regs) / sizeof(u32);
 115 }
 116
 117 /**
 118  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 119  *
 120  * This is for all registers.
 121  */
 122 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 123 {
 124         return num_core_regs() + kvm_arm_num_coproc_regs(vcpu);
 125 }
 126
 127 /**
 128  * kvm_arm_copy_reg_indices - get indices of all registers.
 129  *
 130  * We do core registers right here, then we apppend coproc regs.
 131  */
 132 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 133 {
 134         unsigned int i;
 135         const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
 136
 137         for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
 138                 if (put_user(core_reg | i, uindices))
 139                         return -EFAULT;
 140                 uindices++;
 141         }
 142
 143         return kvm_arm_copy_coproc_indices(vcpu, uindices);
 144 }
 145
 146 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 147 {
 148         /* We currently use nothing arch-specific in upper 32 bits */
 149         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 150                 return -EINVAL;
 151
 152         /* Register group 16 means we want a core register. */
 153         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 154                 return get_core_reg(vcpu, reg);
 155
 156         return kvm_arm_coproc_get_reg(vcpu, reg);
 157 }
 158
 159 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 160 {
 161         /* We currently use nothing arch-specific in upper 32 bits */
 162         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 163                 return -EINVAL;
 164
 165         /* Register group 16 means we set a core register. */
 166         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 167                 return set_core_reg(vcpu, reg);
 168
 169         return kvm_arm_coproc_set_reg(vcpu, reg);
 170 }
 171
 172 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 173                                   struct kvm_sregs *sregs)
 174 {
 175         return -EINVAL;
 176 }
 177
 178 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 179                                   struct kvm_sregs *sregs)
 180 {
 181         return -EINVAL;
 182 }
 183
 184 int __attribute_const__ kvm_target_cpu(void)
 185 {
 186         unsigned long implementor = read_cpuid_implementor();
 187         unsigned long part_number = read_cpuid_part_number();
 188
 189         if (implementor != ARM_CPU_IMP_ARM)
 190                 return -EINVAL;
 191
 192         switch (part_number) {
 193         case ARM_CPU_PART_CORTEX_A15:
 194                 return KVM_ARM_TARGET_CORTEX_A15;
 195         default:
 196                 return -EINVAL;
 197         }
 198 }
 199
 200 int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
 201                         const struct kvm_vcpu_init *init)
 202 {
 203         unsigned int i;
 204
 205         /* We can only do a cortex A15 for now. */
 206         if (init->target != kvm_target_cpu())
 207                 return -EINVAL;
 208
 209         vcpu->arch.target = init->target;
 210         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 211
 212         /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
 213         for (i = 0; i < sizeof(init->features) * 8; i++) {
 214                 if (test_bit(i, (void *)init->features)) {
 215                         if (i >= KVM_VCPU_MAX_FEATURES)
 216                                 return -ENOENT;
 217                         set_bit(i, vcpu->arch.features);
 218                 }
 219         }
 220
 221         /* Now we know what it is, we can reset it. */
 222         return kvm_reset_vcpu(vcpu);
 223 }
 224
 225 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 226 {
 227         return -EINVAL;
 228 }
 229
 230 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 231 {
 232         return -EINVAL;
 233 }
 234
 235 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 236                                   struct kvm_translation *tr)
 237 {
 238         return -EINVAL;
 239 }