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_emulate.h>
  29 #include <asm/kvm_coproc.h>
  30
  31 #define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
  32 #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
  33
  34 struct kvm_stats_debugfs_item debugfs_entries[] = {
  35         VCPU_STAT(hvc_exit_stat),
  36         VCPU_STAT(wfe_exit_stat),
  37         VCPU_STAT(wfi_exit_stat),
  38         VCPU_STAT(mmio_exit_user),
  39         VCPU_STAT(mmio_exit_kernel),
  40         VCPU_STAT(exits),
  41         { NULL }
  42 };
  43
  44 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  45 {
  46         return 0;
  47 }
  48
  49 static u64 core_reg_offset_from_id(u64 id)
  50 {
  51         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  52 }
  53
  54 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  55 {
  56         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  57         struct kvm_regs *regs = &vcpu->arch.ctxt.gp_regs;
  58         u64 off;
  59
  60         if (KVM_REG_SIZE(reg->id) != 4)
  61                 return -ENOENT;
  62
  63         /* Our ID is an index into the kvm_regs struct. */
  64         off = core_reg_offset_from_id(reg->id);
  65         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  66                 return -ENOENT;
  67
  68         return put_user(((u32 *)regs)[off], uaddr);
  69 }
  70
  71 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  72 {
  73         u32 __user *uaddr = (u32 __user *)(long)reg->addr;
  74         struct kvm_regs *regs = &vcpu->arch.ctxt.gp_regs;
  75         u64 off, val;
  76
  77         if (KVM_REG_SIZE(reg->id) != 4)
  78                 return -ENOENT;
  79
  80         /* Our ID is an index into the kvm_regs struct. */
  81         off = core_reg_offset_from_id(reg->id);
  82         if (off >= sizeof(*regs) / KVM_REG_SIZE(reg->id))
  83                 return -ENOENT;
  84
  85         if (get_user(val, uaddr) != 0)
  86                 return -EFAULT;
  87
  88         if (off == KVM_REG_ARM_CORE_REG(usr_regs.ARM_cpsr)) {
  89                 unsigned long mode = val & MODE_MASK;
  90                 switch (mode) {
  91                 case USR_MODE:
  92                 case FIQ_MODE:
  93                 case IRQ_MODE:
  94                 case SVC_MODE:
  95                 case ABT_MODE:
  96                 case UND_MODE:
  97                         break;
  98                 default:
  99                         return -EINVAL;
 100                 }
 101         }
 102
 103         ((u32 *)regs)[off] = val;
 104         return 0;
 105 }
 106
 107 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 108 {
 109         return -EINVAL;
 110 }
 111
 112 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 113 {
 114         return -EINVAL;
 115 }
 116
 117 #define NUM_TIMER_REGS 3
 118
 119 static bool is_timer_reg(u64 index)
 120 {
 121         switch (index) {
 122         case KVM_REG_ARM_TIMER_CTL:
 123         case KVM_REG_ARM_TIMER_CNT:
 124         case KVM_REG_ARM_TIMER_CVAL:
 125                 return true;
 126         }
 127         return false;
 128 }
 129
 130 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 131 {
 132         if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 133                 return -EFAULT;
 134         uindices++;
 135         if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 136                 return -EFAULT;
 137         uindices++;
 138         if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 139                 return -EFAULT;
 140
 141         return 0;
 142 }
 143
 144 static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 145 {
 146         void __user *uaddr = (void __user *)(long)reg->addr;
 147         u64 val;
 148         int ret;
 149
 150         ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 151         if (ret != 0)
 152                 return -EFAULT;
 153
 154         return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 155 }
 156
 157 static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 158 {
 159         void __user *uaddr = (void __user *)(long)reg->addr;
 160         u64 val;
 161
 162         val = kvm_arm_timer_get_reg(vcpu, reg->id);
 163         return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
 164 }
 165
 166 static unsigned long num_core_regs(void)
 167 {
 168         return sizeof(struct kvm_regs) / sizeof(u32);
 169 }
 170
 171 /**
 172  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 173  *
 174  * This is for all registers.
 175  */
 176 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 177 {
 178         return num_core_regs() + kvm_arm_num_coproc_regs(vcpu)
 179                 + NUM_TIMER_REGS;
 180 }
 181
 182 /**
 183  * kvm_arm_copy_reg_indices - get indices of all registers.
 184  *
 185  * We do core registers right here, then we apppend coproc regs.
 186  */
 187 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 188 {
 189         unsigned int i;
 190         const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
 191         int ret;
 192
 193         for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
 194                 if (put_user(core_reg | i, uindices))
 195                         return -EFAULT;
 196                 uindices++;
 197         }
 198
 199         ret = copy_timer_indices(vcpu, uindices);
 200         if (ret)
 201                 return ret;
 202         uindices += NUM_TIMER_REGS;
 203
 204         return kvm_arm_copy_coproc_indices(vcpu, uindices);
 205 }
 206
 207 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 208 {
 209         /* We currently use nothing arch-specific in upper 32 bits */
 210         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 211                 return -EINVAL;
 212
 213         /* Register group 16 means we want a core register. */
 214         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 215                 return get_core_reg(vcpu, reg);
 216
 217         if (is_timer_reg(reg->id))
 218                 return get_timer_reg(vcpu, reg);
 219
 220         return kvm_arm_coproc_get_reg(vcpu, reg);
 221 }
 222
 223 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 224 {
 225         /* We currently use nothing arch-specific in upper 32 bits */
 226         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 227                 return -EINVAL;
 228
 229         /* Register group 16 means we set a core register. */
 230         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 231                 return set_core_reg(vcpu, reg);
 232
 233         if (is_timer_reg(reg->id))
 234                 return set_timer_reg(vcpu, reg);
 235
 236         return kvm_arm_coproc_set_reg(vcpu, reg);
 237 }
 238
 239 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 240                                   struct kvm_sregs *sregs)
 241 {
 242         return -EINVAL;
 243 }
 244
 245 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 246                                   struct kvm_sregs *sregs)
 247 {
 248         return -EINVAL;
 249 }
 250
 251 int __attribute_const__ kvm_target_cpu(void)
 252 {
 253         switch (read_cpuid_part()) {
 254         case ARM_CPU_PART_CORTEX_A7:
 255                 return KVM_ARM_TARGET_CORTEX_A7;
 256         case ARM_CPU_PART_CORTEX_A15:
 257                 return KVM_ARM_TARGET_CORTEX_A15;
 258         default:
 259                 return -EINVAL;
 260         }
 261 }
 262
 263 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 264 {
 265         int target = kvm_target_cpu();
 266
 267         if (target < 0)
 268                 return -ENODEV;
 269
 270         memset(init, 0, sizeof(*init));
 271
 272         /*
 273          * For now, we don't return any features.
 274          * In future, we might use features to return target
 275          * specific features available for the preferred
 276          * target type.
 277          */
 278         init->target = (__u32)target;
 279
 280         return 0;
 281 }
 282
 283 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 284 {
 285         return -EINVAL;
 286 }
 287
 288 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 289 {
 290         return -EINVAL;
 291 }
 292
 293 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 294                                   struct kvm_translation *tr)
 295 {
 296         return -EINVAL;
 297 }
 298
 299 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 300                                         struct kvm_guest_debug *dbg)
 301 {
 302         return -EINVAL;
 303 }