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_emulate.h>
  32 #include <asm/kvm_coproc.h>
  33
  34 #include "trace.h"
  35
  36 #define VM_STAT(x) { #x, offsetof(struct kvm, stat.x), KVM_STAT_VM }
  37 #define VCPU_STAT(x) { #x, offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU }
  38
  39 struct kvm_stats_debugfs_item debugfs_entries[] = {
  40         VCPU_STAT(hvc_exit_stat),
  41         VCPU_STAT(wfe_exit_stat),
  42         VCPU_STAT(wfi_exit_stat),
  43         VCPU_STAT(mmio_exit_user),
  44         VCPU_STAT(mmio_exit_kernel),
  45         VCPU_STAT(exits),
  46         { NULL }
  47 };
  48
  49 int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
  50 {
  51         return 0;
  52 }
  53
  54 static u64 core_reg_offset_from_id(u64 id)
  55 {
  56         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  57 }
  58
  59 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  60 {
  61         /*
  62          * Because the kvm_regs structure is a mix of 32, 64 and
  63          * 128bit fields, we index it as if it was a 32bit
  64          * array. Hence below, nr_regs is the number of entries, and
  65          * off the index in the "array".
  66          */
  67         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  68         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  69         int nr_regs = sizeof(*regs) / sizeof(__u32);
  70         u32 off;
  71
  72         /* Our ID is an index into the kvm_regs struct. */
  73         off = core_reg_offset_from_id(reg->id);
  74         if (off >= nr_regs ||
  75             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  76                 return -ENOENT;
  77
  78         if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
  79                 return -EFAULT;
  80
  81         return 0;
  82 }
  83
  84 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  85 {
  86         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  87         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  88         int nr_regs = sizeof(*regs) / sizeof(__u32);
  89         __uint128_t tmp;
  90         void *valp = &tmp;
  91         u64 off;
  92         int err = 0;
  93
  94         /* Our ID is an index into the kvm_regs struct. */
  95         off = core_reg_offset_from_id(reg->id);
  96         if (off >= nr_regs ||
  97             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  98                 return -ENOENT;
  99
 100         if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
 101                 return -EINVAL;
 102
 103         if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
 104                 err = -EFAULT;
 105                 goto out;
 106         }
 107
 108         if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
 109                 u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
 110                 switch (mode) {
 111                 case COMPAT_PSR_MODE_USR:
 112                 case COMPAT_PSR_MODE_FIQ:
 113                 case COMPAT_PSR_MODE_IRQ:
 114                 case COMPAT_PSR_MODE_SVC:
 115                 case COMPAT_PSR_MODE_ABT:
 116                 case COMPAT_PSR_MODE_UND:
 117                 case PSR_MODE_EL0t:
 118                 case PSR_MODE_EL1t:
 119                 case PSR_MODE_EL1h:
 120                         break;
 121                 default:
 122                         err = -EINVAL;
 123                         goto out;
 124                 }
 125         }
 126
 127         memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
 128 out:
 129         return err;
 130 }
 131
 132 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 133 {
 134         return -EINVAL;
 135 }
 136
 137 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 138 {
 139         return -EINVAL;
 140 }
 141
 142 static unsigned long num_core_regs(void)
 143 {
 144         return sizeof(struct kvm_regs) / sizeof(__u32);
 145 }
 146
 147 /**
 148  * ARM64 versions of the TIMER registers, always available on arm64
 149  */
 150
 151 #define NUM_TIMER_REGS 3
 152
 153 static bool is_timer_reg(u64 index)
 154 {
 155         switch (index) {
 156         case KVM_REG_ARM_TIMER_CTL:
 157         case KVM_REG_ARM_TIMER_CNT:
 158         case KVM_REG_ARM_TIMER_CVAL:
 159                 return true;
 160         }
 161         return false;
 162 }
 163
 164 static int copy_timer_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 165 {
 166         if (put_user(KVM_REG_ARM_TIMER_CTL, uindices))
 167                 return -EFAULT;
 168         uindices++;
 169         if (put_user(KVM_REG_ARM_TIMER_CNT, uindices))
 170                 return -EFAULT;
 171         uindices++;
 172         if (put_user(KVM_REG_ARM_TIMER_CVAL, uindices))
 173                 return -EFAULT;
 174
 175         return 0;
 176 }
 177
 178 static int set_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 179 {
 180         void __user *uaddr = (void __user *)(long)reg->addr;
 181         u64 val;
 182         int ret;
 183
 184         ret = copy_from_user(&val, uaddr, KVM_REG_SIZE(reg->id));
 185         if (ret != 0)
 186                 return -EFAULT;
 187
 188         return kvm_arm_timer_set_reg(vcpu, reg->id, val);
 189 }
 190
 191 static int get_timer_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 192 {
 193         void __user *uaddr = (void __user *)(long)reg->addr;
 194         u64 val;
 195
 196         val = kvm_arm_timer_get_reg(vcpu, reg->id);
 197         return copy_to_user(uaddr, &val, KVM_REG_SIZE(reg->id));
 198 }
 199
 200 /**
 201  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 202  *
 203  * This is for all registers.
 204  */
 205 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 206 {
 207         return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu)
 208                 + NUM_TIMER_REGS;
 209 }
 210
 211 /**
 212  * kvm_arm_copy_reg_indices - get indices of all registers.
 213  *
 214  * We do core registers right here, then we apppend system regs.
 215  */
 216 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 217 {
 218         unsigned int i;
 219         const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE;
 220         int ret;
 221
 222         for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
 223                 if (put_user(core_reg | i, uindices))
 224                         return -EFAULT;
 225                 uindices++;
 226         }
 227
 228         ret = copy_timer_indices(vcpu, uindices);
 229         if (ret)
 230                 return ret;
 231         uindices += NUM_TIMER_REGS;
 232
 233         return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
 234 }
 235
 236 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 237 {
 238         /* We currently use nothing arch-specific in upper 32 bits */
 239         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 240                 return -EINVAL;
 241
 242         /* Register group 16 means we want a core register. */
 243         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 244                 return get_core_reg(vcpu, reg);
 245
 246         if (is_timer_reg(reg->id))
 247                 return get_timer_reg(vcpu, reg);
 248
 249         return kvm_arm_sys_reg_get_reg(vcpu, reg);
 250 }
 251
 252 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 253 {
 254         /* We currently use nothing arch-specific in upper 32 bits */
 255         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 256                 return -EINVAL;
 257
 258         /* Register group 16 means we set a core register. */
 259         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 260                 return set_core_reg(vcpu, reg);
 261
 262         if (is_timer_reg(reg->id))
 263                 return set_timer_reg(vcpu, reg);
 264
 265         return kvm_arm_sys_reg_set_reg(vcpu, reg);
 266 }
 267
 268 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 269                                   struct kvm_sregs *sregs)
 270 {
 271         return -EINVAL;
 272 }
 273
 274 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 275                                   struct kvm_sregs *sregs)
 276 {
 277         return -EINVAL;
 278 }
 279
 280 int __attribute_const__ kvm_target_cpu(void)
 281 {
 282         unsigned long implementor = read_cpuid_implementor();
 283         unsigned long part_number = read_cpuid_part_number();
 284
 285         switch (implementor) {
 286         case ARM_CPU_IMP_ARM:
 287                 switch (part_number) {
 288                 case ARM_CPU_PART_AEM_V8:
 289                         return KVM_ARM_TARGET_AEM_V8;
 290                 case ARM_CPU_PART_FOUNDATION:
 291                         return KVM_ARM_TARGET_FOUNDATION_V8;
 292                 case ARM_CPU_PART_CORTEX_A53:
 293                         return KVM_ARM_TARGET_CORTEX_A53;
 294                 case ARM_CPU_PART_CORTEX_A57:
 295                         return KVM_ARM_TARGET_CORTEX_A57;
 296                 };
 297                 break;
 298         case ARM_CPU_IMP_APM:
 299                 switch (part_number) {
 300                 case APM_CPU_PART_POTENZA:
 301                         return KVM_ARM_TARGET_XGENE_POTENZA;
 302                 };
 303                 break;
 304         };
 305
 306         /* Return a default generic target */
 307         return KVM_ARM_TARGET_GENERIC_V8;
 308 }
 309
 310 int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init)
 311 {
 312         int target = kvm_target_cpu();
 313
 314         if (target < 0)
 315                 return -ENODEV;
 316
 317         memset(init, 0, sizeof(*init));
 318
 319         /*
 320          * For now, we don't return any features.
 321          * In future, we might use features to return target
 322          * specific features available for the preferred
 323          * target type.
 324          */
 325         init->target = (__u32)target;
 326
 327         return 0;
 328 }
 329
 330 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 331 {
 332         return -EINVAL;
 333 }
 334
 335 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 336 {
 337         return -EINVAL;
 338 }
 339
 340 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 341                                   struct kvm_translation *tr)
 342 {
 343         return -EINVAL;
 344 }
 345
 346 #define KVM_GUESTDBG_VALID_MASK (KVM_GUESTDBG_ENABLE |    \
 347                             KVM_GUESTDBG_USE_SW_BP | \
 348                             KVM_GUESTDBG_USE_HW | \
 349                             KVM_GUESTDBG_SINGLESTEP)
 350
 351 /**
 352  * kvm_arch_vcpu_ioctl_set_guest_debug - set up guest debugging
 353  * @kvm:        pointer to the KVM struct
 354  * @kvm_guest_debug: the ioctl data buffer
 355  *
 356  * This sets up and enables the VM for guest debugging. Userspace
 357  * passes in a control flag to enable different debug types and
 358  * potentially other architecture specific information in the rest of
 359  * the structure.
 360  */
 361 int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
 362                                         struct kvm_guest_debug *dbg)
 363 {
 364         trace_kvm_set_guest_debug(vcpu, dbg->control);
 365
 366         if (dbg->control & ~KVM_GUESTDBG_VALID_MASK)
 367                 return -EINVAL;
 368
 369         if (dbg->control & KVM_GUESTDBG_ENABLE) {
 370                 vcpu->guest_debug = dbg->control;
 371
 372                 /* Hardware assisted Break and Watch points */
 373                 if (vcpu->guest_debug & KVM_GUESTDBG_USE_HW) {
 374                         vcpu->arch.external_debug_state = dbg->arch;
 375                 }
 376
 377         } else {
 378                 /* If not enabled clear all flags */
 379                 vcpu->guest_debug = 0;
 380         }
 381         return 0;
 382 }