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         VCPU_STAT(hvc_exit_stat),
  37         VCPU_STAT(wfe_exit_stat),
  38         VCPU_STAT(wfi_exit_stat),
  39         VCPU_STAT(mmio_exit_user),
  40         VCPU_STAT(mmio_exit_kernel),
  41         VCPU_STAT(exits),
  42         { NULL }
  43 };
  44
  45 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  46 {
  47         return 0;
  48 }
  49
  50 static u64 core_reg_offset_from_id(u64 id)
  51 {
  52         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  53 }
  54
  55 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  56 {
  57         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  58         struct kvm_regs *regs = &vcpu->arch.regs;
  59         u64 off;
  60
  61         if (KVM_REG_SIZE(reg->id) != 4)
  62                 return -ENOENT;
  63
  64         /* Our ID is an index into the kvm_regs struct. */
  65         off = core_reg_offset_from_id(reg->id);
  66         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  67                 return -ENOENT;
  68
  69         return put_user(((u32 *)regs)[off], uaddr);
  70 }
  71
  72 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  73 {
  74         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  75         struct kvm_regs *regs = &vcpu->arch.regs;
  76         u64 off, val;
  77
  78         if (KVM_REG_SIZE(reg->id) != 4)
  79                 return -ENOENT;
  80
  81         /* Our ID is an index into the kvm_regs struct. */
  82         off = core_reg_offset_from_id(reg->id);
  83         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  84                 return -ENOENT;
  85
  86         if (get_user(val, uaddr) != 0)
  87                 return -EFAULT;
  88
  89         if (off == KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr)) {
  90                 unsigned long mode = val & MODE_MASK;
  91                 switch (mode) {
  92                 case USR_MODE:
  93                 case FIQ_MODE:
  94                 case IRQ_MODE:
  95                 case SVC_MODE:
  96                 case ABT_MODE:
  97                 case UND_MODE:
  98                         break;
  99                 default:
 100                         return -EINVAL;
 101                 }
 102         }
 103
 104         ((u32 *)regs)[off] = val;
 105         return 0;
 106 }
 107
 108 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 109 {
 110         return -EINVAL;
 111 }
 112
 113 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 114 {
 115         return -EINVAL;
 116 }
 117
 118 #define NUM_TIMER_REGS 3
 119
 120 static bool is_timer_reg(u64 index)
 121 {
 122         switch (index) {
 123         case KVM_REG_ARM_TIMER_CTL:
 124         case KVM_REG_ARM_TIMER_CNT:
 125         case KVM_REG_ARM_TIMER_CVAL:
 126                 return true;
 127         }
 128         return false;
 129 }
 130
 131 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 132 {
 133         if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 134                 return -EFAULT;
 135         uindices++;
 136         if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 137                 return -EFAULT;
 138         uindices++;
 139         if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 140                 return -EFAULT;
 141
 142         return 0;
 143 }
 144
 145 static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 146 {
 147         void __user *uaddr = (void __user *)(long)reg->addr;
 148         u64 val;
 149         int ret;
 150
 151         ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 152         if (ret != 0)
 153                 return -EFAULT;
 154
 155         return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 156 }
 157
 158 static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 159 {
 160         void __user *uaddr = (void __user *)(long)reg->addr;
 161         u64 val;
 162
 163         val = kvm_arm_timer_get_reg(vcpu, reg->id);
 164         return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id));
 165 }
 166
 167 static unsigned long num_core_regs(void)
 168 {
 169         return sizeof(struct kvm_regs) / sizeof(u32);
 170 }
 171
 172 /**
 173  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 174  *
 175  * This is for all registers.
 176  */
 177 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 178 {
 179         return num_core_regs() + kvm_arm_num_coproc_regs(vcpu)
 180                 + NUM_TIMER_REGS;
 181 }
 182
 183 /**
 184  * kvm_arm_copy_reg_indices - get indices of all registers.
 185  *
 186  * We do core registers right here, then we apppend coproc regs.
 187  */
 188 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 189 {
 190         unsigned int i;
 191         const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
 192         int ret;
 193
 194         for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
 195                 if (put_user(core_reg | i, uindices))
 196                         return -EFAULT;
 197                 uindices++;
 198         }
 199
 200         ret = copy_timer_indices(vcpu, uindices);
 201         if (ret)
 202                 return ret;
 203         uindices += NUM_TIMER_REGS;
 204
 205         return kvm_arm_copy_coproc_indices(vcpu, uindices);
 206 }
 207
 208 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 209 {
 210         /* We currently use nothing arch-specific in upper 32 bits */
 211         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 212                 return -EINVAL;
 213
 214         /* Register group 16 means we want a core register. */
 215         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 216                 return get_core_reg(vcpu, reg);
 217
 218         if (is_timer_reg(reg->id))
 219                 return get_timer_reg(vcpu, reg);
 220
 221         return kvm_arm_coproc_get_reg(vcpu, reg);
 222 }
 223
 224 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 225 {
 226         /* We currently use nothing arch-specific in upper 32 bits */
 227         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 228                 return -EINVAL;
 229
 230         /* Register group 16 means we set a core register. */
 231         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 232                 return set_core_reg(vcpu, reg);
 233
 234         if (is_timer_reg(reg->id))
 235                 return set_timer_reg(vcpu, reg);
 236
 237         return kvm_arm_coproc_set_reg(vcpu, reg);
 238 }
 239
 240 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 241                                   struct kvm_sregs *sregs)
 242 {
 243         return -EINVAL;
 244 }
 245
 246 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 247                                   struct kvm_sregs *sregs)
 248 {
 249         return -EINVAL;
 250 }
 251
 252 int __attribute_const__ kvm_target_cpu(void)
 253 {
 254         switch (read_cpuid_part()) {
 255         case ARM_CPU_PART_CORTEX_A7:
 256                 return KVM_ARM_TARGET_CORTEX_A7;
 257         case ARM_CPU_PART_CORTEX_A15:
 258                 return KVM_ARM_TARGET_CORTEX_A15;
 259         default:
 260                 return -EINVAL;
 261         }
 262 }
 263
 264 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 265 {
 266         int target = kvm_target_cpu();
 267
 268         if (target < 0)
 269                 return -ENODEV;
 270
 271         memset(init, 0, sizeof(*init));
 272
 273         /*
 274          * For now, we don't return any features.
 275          * In future, we might use features to return target
 276          * specific features available for the preferred
 277          * target type.
 278          */
 279         init->target = (__u32)target;
 280
 281         return 0;
 282 }
 283
 284 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 285 {
 286         return -EINVAL;
 287 }
 288
 289 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 290 {
 291         return -EINVAL;
 292 }
 293
 294 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 295                                   struct kvm_translation *tr)
 296 {
 297         return -EINVAL;
 298 }
 299
 300 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 301                                         struct kvm_guest_debug *dbg)
 302 {
 303         return -EINVAL;
 304 }