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