LXR linux/arch/arm64/kvm/guest.c

   1/*
   2 * Copyright (C) 2012,2013 - ARM Ltd
   3 * Author: Marc Zyngier <marc.zyngier@arm.com>
   4 *
   5 * Derived from arch/arm/kvm/guest.c:
   6 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   7 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as
  11 * published by the Free Software Foundation.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22#include <linux/errno.h>
  23#include <linux/err.h>
  24#include <linux/kvm_host.h>
  25#include <linux/module.h>
  26#include <linux/vmalloc.h>
  27#include <linux/fs.h>
  28#include <asm/cputype.h>
  29#include <asm/uaccess.h>
  30#include <asm/kvm.h>
  31#include <asm/kvm_asm.h>
  32#include <asm/kvm_emulate.h>
  33#include <asm/kvm_coproc.h>
  34
  35struct kvm_stats_debugfs_item debugfs_entries[] = {
  36        { NULL }
  37};
  38
  39int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  40{
  41        return 0;
  42}
  43
  44static 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
  49static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  50{
  51        /*
  52         * Because the kvm_regs structure is a mix of 32, 64 and
  53         * 128bit fields, we index it as if it was a 32bit
  54         * array. Hence below, nr_regs is the number of entries, and
  55         * off the index in the "array".
  56         */
  57        __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  58        struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  59        int nr_regs = sizeof(*regs) / sizeof(__u32);
  60        u32 off;
  61
  62        /* Our ID is an index into the kvm_regs struct. */
  63        off = core_reg_offset_from_id(reg->id);
  64        if (off >= nr_regs ||
  65            (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  66                return -ENOENT;
  67
  68        if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
  69                return -EFAULT;
  70
  71        return 0;
  72}
  73
  74static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  75{
  76        __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  77        struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  78        int nr_regs = sizeof(*regs) / sizeof(__u32);
  79        __uint128_t tmp;
  80        void *valp = &tmp;
  81        u64 off;
  82        int err = 0;
  83
  84        /* Our ID is an index into the kvm_regs struct. */
  85        off = core_reg_offset_from_id(reg->id);
  86        if (off >= nr_regs ||
  87            (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  88                return -ENOENT;
  89
  90        if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
  91                return -EINVAL;
  92
  93        if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
  94                err = -EFAULT;
  95                goto out;
  96        }
  97
  98        if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
  99                u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
 100                switch (mode) {
 101                case COMPAT_PSR_MODE_USR:
 102                case COMPAT_PSR_MODE_FIQ:
 103                case COMPAT_PSR_MODE_IRQ:
 104                case COMPAT_PSR_MODE_SVC:
 105                case COMPAT_PSR_MODE_ABT:
 106                case COMPAT_PSR_MODE_UND:
 107                case PSR_MODE_EL0t:
 108                case PSR_MODE_EL1t:
 109                case PSR_MODE_EL1h:
 110                        break;
 111                default:
 112                        err = -EINVAL;
 113                        goto out;
 114                }
 115        }
 116
 117        memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
 118out:
 119        return err;
 120}
 121
 122int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 123{
 124        return -EINVAL;
 125}
 126
 127int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 128{
 129        return -EINVAL;
 130}
 131
 132static unsigned long num_core_regs(void)
 133{
 134        return sizeof(struct kvm_regs) / sizeof(__u32);
 135}
 136
 137/**
 138 * ARM64 versions of the TIMER registers, always available on arm64
 139 */
 140
 141#define NUM_TIMER_REGS 3
 142
 143static bool is_timer_reg(u64 index)
 144{
 145        switch (index) {
 146        case KVM_REG_ARM_TIMER_CTL:
 147        case KVM_REG_ARM_TIMER_CNT:
 148        case KVM_REG_ARM_TIMER_CVAL:
 149                return true;
 150        }
 151        return false;
 152}
 153
 154static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 155{
 156        if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 157                return -EFAULT;
 158        uindices++;
 159        if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 160                return -EFAULT;
 161        uindices++;
 162        if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 163                return -EFAULT;
 164
 165        return 0;
 166}
 167
 168static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 169{
 170        void __user *uaddr = (void __user *)(long)reg->addr;
 171        u64 val;
 172        int ret;
 173
 174        ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 175        if (ret != 0)
 176                return -EFAULT;
 177
 178        return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 179}
 180
 181static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 182{
 183        void __user *uaddr = (void __user *)(long)reg->addr;
 184        u64 val;
 185
 186        val = kvm_arm_timer_get_reg(vcpu, reg->id);
 187        return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id));
 188}
 189
 190/**
 191 * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 192 *
 193 * This is for all registers.
 194 */
 195unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 196{
 197        return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu)
 198                + NUM_TIMER_REGS;
 199}
 200
 201/**
 202 * kvm_arm_copy_reg_indices - get indices of all registers.
 203 *
 204 * We do core registers right here, then we apppend system regs.
 205 */
 206int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 207{
 208        unsigned int i;
 209        const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE;
 210        int ret;
 211
 212        for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
 213                if (put_user(core_reg | i, uindices))
 214                        return -EFAULT;
 215                uindices++;
 216        }
 217
 218        ret = copy_timer_indices(vcpu, uindices);
 219        if (ret)
 220                return ret;
 221        uindices += NUM_TIMER_REGS;
 222
 223        return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
 224}
 225
 226int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 227{
 228        /* We currently use nothing arch-specific in upper 32 bits */
 229        if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 230                return -EINVAL;
 231
 232        /* Register group 16 means we want a core register. */
 233        if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 234                return get_core_reg(vcpu, reg);
 235
 236        if (is_timer_reg(reg->id))
 237                return get_timer_reg(vcpu, reg);
 238
 239        return kvm_arm_sys_reg_get_reg(vcpu, reg);
 240}
 241
 242int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 243{
 244        /* We currently use nothing arch-specific in upper 32 bits */
 245        if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 246                return -EINVAL;
 247
 248        /* Register group 16 means we set a core register. */
 249        if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 250                return set_core_reg(vcpu, reg);
 251
 252        if (is_timer_reg(reg->id))
 253                return set_timer_reg(vcpu, reg);
 254
 255        return kvm_arm_sys_reg_set_reg(vcpu, reg);
 256}
 257
 258int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 259                                  struct kvm_sregs *sregs)
 260{
 261        return -EINVAL;
 262}
 263
 264int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 265                                  struct kvm_sregs *sregs)
 266{
 267        return -EINVAL;
 268}
 269
 270int __attribute_const__ kvm_target_cpu(void)
 271{
 272        unsigned long implementor = read_cpuid_implementor();
 273        unsigned long part_number = read_cpuid_part_number();
 274
 275        switch (implementor) {
 276        case ARM_CPU_IMP_ARM:
 277                switch (part_number) {
 278                case ARM_CPU_PART_AEM_V8:
 279                        return KVM_ARM_TARGET_AEM_V8;
 280                case ARM_CPU_PART_FOUNDATION:
 281                        return KVM_ARM_TARGET_FOUNDATION_V8;
 282                case ARM_CPU_PART_CORTEX_A53:
 283                        return KVM_ARM_TARGET_CORTEX_A53;
 284                case ARM_CPU_PART_CORTEX_A57:
 285                        return KVM_ARM_TARGET_CORTEX_A57;
 286                };
 287                break;
 288        case ARM_CPU_IMP_APM:
 289                switch (part_number) {
 290                case APM_CPU_PART_POTENZA:
 291                        return KVM_ARM_TARGET_XGENE_POTENZA;
 292                };
 293                break;
 294        };
 295
 296        return -EINVAL;
 297}
 298
 299int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 300{
 301        int target = kvm_target_cpu();
 302
 303        if (target < 0)
 304                return -ENODEV;
 305
 306        memset(init, 0, sizeof(*init));
 307
 308        /*
 309         * For now, we don't return any features.
 310         * In future, we might use features to return target
 311         * specific features available for the preferred
 312         * target type.
 313         */
 314        init->target = (__u32)target;
 315
 316        return 0;
 317}
 318
 319int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 320{
 321        return -EINVAL;
 322}
 323
 324int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 325{
 326        return -EINVAL;
 327}
 328
 329int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 330                                  struct kvm_translation *tr)
 331{
 332        return -EINVAL;
 333}
 334