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 <kvm/arm_psci.h>
  29 #include <asm/cputype.h>
  30 #include <linux/uaccess.h>
  31 #include <asm/kvm.h>
  32 #include <asm/kvm_emulate.h>
  33 #include <asm/kvm_coproc.h>
  34
  35 #include "trace.h"
  36
  37 #define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
  38 #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
  39
  40 struct kvm_stats_debugfs_item debugfs_entries[] = {
  41         VCPU_STAT(hvc_exit_stat),
  42         VCPU_STAT(wfe_exit_stat),
  43         VCPU_STAT(wfi_exit_stat),
  44         VCPU_STAT(mmio_exit_user),
  45         VCPU_STAT(mmio_exit_kernel),
  46         VCPU_STAT(exits),
  47         { NULL }
  48 };
  49
  50 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  51 {
  52         return 0;
  53 }
  54
  55 static u64 core_reg_offset_from_id(u64 id)
  56 {
  57         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  58 }
  59
  60 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  61 {
  62         /*
  63          * Because the kvm_regs structure is a mix of 32, 64 and
  64          * 128bit fields, we index it as if it was a 32bit
  65          * array. Hence below, nr_regs is the number of entries, and
  66          * off the index in the "array".
  67          */
  68         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  69         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  70         int nr_regs = sizeof(*regs) / sizeof(__u32);
  71         u32 off;
  72
  73         /* Our ID is an index into the kvm_regs struct. */
  74         off = core_reg_offset_from_id(reg->id);
  75         if (off >= nr_regs ||
  76             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  77                 return -ENOENT;
  78
  79         if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
  80                 return -EFAULT;
  81
  82         return 0;
  83 }
  84
  85 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  86 {
  87         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  88         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  89         int nr_regs = sizeof(*regs) / sizeof(__u32);
  90         __uint128_t tmp;
  91         void *valp = &tmp;
  92         u64 off;
  93         int err = 0;
  94
  95         /* Our ID is an index into the kvm_regs struct. */
  96         off = core_reg_offset_from_id(reg->id);
  97         if (off >= nr_regs ||
  98             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  99                 return -ENOENT;
 100
 101         if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
 102                 return -EINVAL;
 103
 104         if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
 105                 err = -EFAULT;
 106                 goto out;
 107         }
 108
 109         if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
 110                 u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
 111                 switch (mode) {
 112                 case COMPAT_PSR_MODE_USR:
 113                 case COMPAT_PSR_MODE_FIQ:
 114                 case COMPAT_PSR_MODE_IRQ:
 115                 case COMPAT_PSR_MODE_SVC:
 116                 case COMPAT_PSR_MODE_ABT:
 117                 case COMPAT_PSR_MODE_UND:
 118                 case PSR_MODE_EL0t:
 119                 case PSR_MODE_EL1t:
 120                 case PSR_MODE_EL1h:
 121                         break;
 122                 default:
 123                         err = -EINVAL;
 124                         goto out;
 125                 }
 126         }
 127
 128         memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
 129 out:
 130         return err;
 131 }
 132
 133 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 134 {
 135         return -EINVAL;
 136 }
 137
 138 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 139 {
 140         return -EINVAL;
 141 }
 142
 143 static unsigned long num_core_regs(void)
 144 {
 145         return sizeof(struct kvm_regs) / sizeof(__u32);
 146 }
 147
 148 /**
 149  * ARM64 versions of the TIMER registers, always available on arm64
 150  */
 151
 152 #define NUM_TIMER_REGS 3
 153
 154 static bool is_timer_reg(u64 index)
 155 {
 156         switch (index) {
 157         case KVM_REG_ARM_TIMER_CTL:
 158         case KVM_REG_ARM_TIMER_CNT:
 159         case KVM_REG_ARM_TIMER_CVAL:
 160                 return true;
 161         }
 162         return false;
 163 }
 164
 165 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 166 {
 167         if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 168                 return -EFAULT;
 169         uindices++;
 170         if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 171                 return -EFAULT;
 172         uindices++;
 173         if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 174                 return -EFAULT;
 175
 176         return 0;
 177 }
 178
 179 static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 180 {
 181         void __user *uaddr = (void __user *)(long)reg->addr;
 182         u64 val;
 183         int ret;
 184
 185         ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 186         if (ret != 0)
 187                 return -EFAULT;
 188
 189         return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 190 }
 191
 192 static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 193 {
 194         void __user *uaddr = (void __user *)(long)reg->addr;
 195         u64 val;
 196
 197         val = kvm_arm_timer_get_reg(vcpu, reg->id);
 198         return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id)) ? -EFAULT : 0;
 199 }
 200
 201 /**
 202  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 203  *
 204  * This is for all registers.
 205  */
 206 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 207 {
 208         return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu)
 209                 + kvm_arm_get_fw_num_regs(vcpu) + NUM_TIMER_REGS;
 210 }
 211
 212 /**
 213  * kvm_arm_copy_reg_indices - get indices of all registers.
 214  *
 215  * We do core registers right here, then we append system regs.
 216  */
 217 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 218 {
 219         unsigned int i;
 220         const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE;
 221         int ret;
 222
 223         for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
 224                 if (put_user(core_reg | i, uindices))
 225                         return -EFAULT;
 226                 uindices++;
 227         }
 228
 229         ret = kvm_arm_copy_fw_reg_indices(vcpu, uindices);
 230         if (ret)
 231                 return ret;
 232         uindices += kvm_arm_get_fw_num_regs(vcpu);
 233
 234         ret = copy_timer_indices(vcpu, uindices);
 235         if (ret)
 236                 return ret;
 237         uindices += NUM_TIMER_REGS;
 238
 239         return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
 240 }
 241
 242 int kvm_arm_get_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 want a core register. */
 249         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 250                 return get_core_reg(vcpu, reg);
 251
 252         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW)
 253                 return kvm_arm_get_fw_reg(vcpu, reg);
 254
 255         if (is_timer_reg(reg->id))
 256                 return get_timer_reg(vcpu, reg);
 257
 258         return kvm_arm_sys_reg_get_reg(vcpu, reg);
 259 }
 260
 261 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 262 {
 263         /* We currently use nothing arch-specific in upper 32 bits */
 264         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 265                 return -EINVAL;
 266
 267         /* Register group 16 means we set a core register. */
 268         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 269                 return set_core_reg(vcpu, reg);
 270
 271         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_FW)
 272                 return kvm_arm_set_fw_reg(vcpu, reg);
 273
 274         if (is_timer_reg(reg->id))
 275                 return set_timer_reg(vcpu, reg);
 276
 277         return kvm_arm_sys_reg_set_reg(vcpu, reg);
 278 }
 279
 280 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 281                                   struct kvm_sregs *sregs)
 282 {
 283         return -EINVAL;
 284 }
 285
 286 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 287                                   struct kvm_sregs *sregs)
 288 {
 289         return -EINVAL;
 290 }
 291
 292 int __attribute_const__ kvm_target_cpu(void)
 293 {
 294         unsigned long implementor = read_cpuid_implementor();
 295         unsigned long part_number = read_cpuid_part_number();
 296
 297         switch (implementor) {
 298         case ARM_CPU_IMP_ARM:
 299                 switch (part_number) {
 300                 case ARM_CPU_PART_AEM_V8:
 301                         return KVM_ARM_TARGET_AEM_V8;
 302                 case ARM_CPU_PART_FOUNDATION:
 303                         return KVM_ARM_TARGET_FOUNDATION_V8;
 304                 case ARM_CPU_PART_CORTEX_A53:
 305                         return KVM_ARM_TARGET_CORTEX_A53;
 306                 case ARM_CPU_PART_CORTEX_A57:
 307                         return KVM_ARM_TARGET_CORTEX_A57;
 308                 };
 309                 break;
 310         case ARM_CPU_IMP_APM:
 311                 switch (part_number) {
 312                 case APM_CPU_PART_POTENZA:
 313                         return KVM_ARM_TARGET_XGENE_POTENZA;
 314                 };
 315                 break;
 316         };
 317
 318         /* Return a default generic target */
 319         return KVM_ARM_TARGET_GENERIC_V8;
 320 }
 321
 322 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 323 {
 324         int target = kvm_target_cpu();
 325
 326         if (target < 0)
 327                 return -ENODEV;
 328
 329         memset(init, 0, sizeof(*init));
 330
 331         /*
 332          * For now, we don't return any features.
 333          * In future, we might use features to return target
 334          * specific features available for the preferred
 335          * target type.
 336          */
 337         init->target = (__u32)target;
 338
 339         return 0;
 340 }
 341
 342 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 343 {
 344         return -EINVAL;
 345 }
 346
 347 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 348 {
 349         return -EINVAL;
 350 }
 351
 352 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 353                                   struct kvm_translation *tr)
 354 {
 355         return -EINVAL;
 356 }
 357
 358 #define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE |    \
 359                             KVM_GUESTDBG_USE_SW_BP | \
 360                             KVM_GUESTDBG_USE_HW | \
 361                             KVM_GUESTDBG_SINGLESTEP)
 362
 363 /**
 364  * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging
 365  * @kvm:        pointer to the KVM struct
 366  * @kvm_guest_debug: the ioctl data buffer
 367  *
 368  * This sets up and enables the VM for guest debugging. Userspace
 369  * passes in a control flag to enable different debug types and
 370  * potentially other architecture specific information in the rest of
 371  * the structure.
 372  */
 373 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 374                                         struct kvm_guest_debug *dbg)
 375 {
 376         int ret = 0;
 377
 378         trace_kvm_set_guest_debug(vcpu, dbg->control);
 379
 380         if (dbg->control & ~KVM_GUESTDBG_VALID_MASK) {
 381                 ret = -EINVAL;
 382                 goto out;
 383         }
 384
 385         if (dbg->control & KVM_GUESTDBG_ENABLE) {
 386                 vcpu->guest_debug = dbg->control;
 387
 388                 /* Hardware assisted Break and Watch points */
 389                 if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
 390                         vcpu->arch.external_debug_state = dbg->arch;
 391                 }
 392
 393         } else {
 394                 /* If not enabled clear all flags */
 395                 vcpu->guest_debug = 0;
 396         }
 397
 398 out:
 399         return ret;
 400 }
 401
 402 int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
 403                                struct kvm_device_attr *attr)
 404 {
 405         int ret;
 406
 407         switch (attr->group) {
 408         case KVM_ARM_VCPU_PMU_V3_CTRL:
 409                 ret = kvm_arm_pmu_v3_set_attr(vcpu, attr);
 410                 break;
 411         case KVM_ARM_VCPU_TIMER_CTRL:
 412                 ret = kvm_arm_timer_set_attr(vcpu, attr);
 413                 break;
 414         default:
 415                 ret = -ENXIO;
 416                 break;
 417         }
 418
 419         return ret;
 420 }
 421
 422 int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
 423                                struct kvm_device_attr *attr)
 424 {
 425         int ret;
 426
 427         switch (attr->group) {
 428         case KVM_ARM_VCPU_PMU_V3_CTRL:
 429                 ret = kvm_arm_pmu_v3_get_attr(vcpu, attr);
 430                 break;
 431         case KVM_ARM_VCPU_TIMER_CTRL:
 432                 ret = kvm_arm_timer_get_attr(vcpu, attr);
 433                 break;
 434         default:
 435                 ret = -ENXIO;
 436                 break;
 437         }
 438
 439         return ret;
 440 }
 441
 442 int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
 443                                struct kvm_device_attr *attr)
 444 {
 445         int ret;
 446
 447         switch (attr->group) {
 448         case KVM_ARM_VCPU_PMU_V3_CTRL:
 449                 ret = kvm_arm_pmu_v3_has_attr(vcpu, attr);
 450                 break;
 451         case KVM_ARM_VCPU_TIMER_CTRL:
 452                 ret = kvm_arm_timer_has_attr(vcpu, attr);
 453                 break;
 454         default:
 455                 ret = -ENXIO;
 456                 break;
 457         }
 458
 459         return ret;
 460 }