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 <kvm/arm_psci.h>
  26 #include <asm/cputype.h>
  27 #include <asm/uaccess.h>
  28 #include <asm/kvm.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.ctxt.gp_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.ctxt.gp_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)) ? -EFAULT : 0;
 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                 + kvm_arm_get_fw_num_regs(vcpu)
 181                 + NUM_TIMER_REGS;
 182 }
 183
 184 /**
 185  * kvm_arm_copy_reg_indices - get indices of all registers.
 186  *
 187  * We do core registers right here, then we append coproc regs.
 188  */
 189 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 190 {
 191         unsigned int i;
 192         const u64 core_reg = KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_CORE;
 193         int ret;
 194
 195         for (i = 0; i < sizeof(struct kvm_regs)/sizeof(u32); i++) {
 196                 if (put_user(core_reg | i, uindices))
 197                         return -EFAULT;
 198                 uindices++;
 199         }
 200
 201         ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices);
 202         if (ret)
 203                 return ret;
 204         uindices += kvm_arm_get_fw_num_regs(vcpu);
 205
 206         ret = copy_timer_indices(vcpu, uindices);
 207         if (ret)
 208                 return ret;
 209         uindices += NUM_TIMER_REGS;
 210
 211         return kvm_arm_copy_coproc_indices(vcpu, uindices);
 212 }
 213
 214 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 215 {
 216         /* We currently use nothing arch-specific in upper 32 bits */
 217         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 218                 return -EINVAL;
 219
 220         /* Register group 16 means we want a core register. */
 221         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 222                 return get_core_reg(vcpu, reg);
 223
 224         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW)
 225                 return kvm_arm_get_fw_reg(vcpu, reg);
 226
 227         if (is_timer_reg(reg->id))
 228                 return get_timer_reg(vcpu, reg);
 229
 230         return kvm_arm_coproc_get_reg(vcpu, reg);
 231 }
 232
 233 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 234 {
 235         /* We currently use nothing arch-specific in upper 32 bits */
 236         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM >> 32)
 237                 return -EINVAL;
 238
 239         /* Register group 16 means we set a core register. */
 240         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 241                 return set_core_reg(vcpu, reg);
 242
 243         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW)
 244                 return kvm_arm_set_fw_reg(vcpu, reg);
 245
 246         if (is_timer_reg(reg->id))
 247                 return set_timer_reg(vcpu, reg);
 248
 249         return kvm_arm_coproc_set_reg(vcpu, reg);
 250 }
 251
 252 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 253                                   struct kvm_sregs *sregs)
 254 {
 255         return -EINVAL;
 256 }
 257
 258 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 259                                   struct kvm_sregs *sregs)
 260 {
 261         return -EINVAL;
 262 }
 263
 264 int __attribute_const__ kvm_target_cpu(void)
 265 {
 266         switch (read_cpuid_part()) {
 267         case ARM_CPU_PART_CORTEX_A7:
 268                 return KVM_ARM_TARGET_CORTEX_A7;
 269         case ARM_CPU_PART_CORTEX_A15:
 270                 return KVM_ARM_TARGET_CORTEX_A15;
 271         default:
 272                 return -EINVAL;
 273         }
 274 }
 275
 276 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 277 {
 278         int target = kvm_target_cpu();
 279
 280         if (target < 0)
 281                 return -ENODEV;
 282
 283         memset(init, 0, sizeof(*init));
 284
 285         /*
 286          * For now, we don't return any features.
 287          * In future, we might use features to return target
 288          * specific features available for the preferred
 289          * target type.
 290          */
 291         init->target = (__u32)target;
 292
 293         return 0;
 294 }
 295
 296 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 297 {
 298         return -EINVAL;
 299 }
 300
 301 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 302 {
 303         return -EINVAL;
 304 }
 305
 306 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 307                                   struct kvm_translation *tr)
 308 {
 309         return -EINVAL;
 310 }
 311
 312 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 313                                         struct kvm_guest_debug *dbg)
 314 {
 315         return -EINVAL;
 316 }