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
  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         /*
  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
  74 static 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));
 118 out:
 119         return err;
 120 }
 121
 122 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 123 {
 124         return -EINVAL;
 125 }
 126
 127 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 128 {
 129         return -EINVAL;
 130 }
 131
 132 static 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
 143 static 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
 154 static 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
 168 static 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
 181 static 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  */
 195 unsigned 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  */
 206 int 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
 226 int 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
 242 int 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
 258 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 259                                   struct kvm_sregs *sregs)
 260 {
 261         return -EINVAL;
 262 }
 263
 264 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 265                                   struct kvm_sregs *sregs)
 266 {
 267         return -EINVAL;
 268 }
 269
 270 int __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
 299 int 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
 319 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 320 {
 321         return -EINVAL;
 322 }
 323
 324 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 325 {
 326         return -EINVAL;
 327 }
 328
 329 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 330                                   struct kvm_translation *tr)
 331 {
 332         return -EINVAL;
 333 }