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         vcpu->arch.hcr_el2 = HCR_GUEST_FLAGS;
  42         return 0;
  43 }
  44
  45 static u64 core_reg_offset_from_id(u64 id)
  46 {
  47         return id & ~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE);
  48 }
  49
  50 static int get_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  51 {
  52         /*
  53          * Because the kvm_regs structure is a mix of 32, 64 and
  54          * 128bit fields, we index it as if it was a 32bit
  55          * array. Hence below, nr_regs is the number of entries, and
  56          * off the index in the "array".
  57          */
  58         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  59         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  60         int nr_regs = sizeof(*regs) / sizeof(__u32);
  61         u32 off;
  62
  63         /* Our ID is an index into the kvm_regs struct. */
  64         off = core_reg_offset_from_id(reg->id);
  65         if (off >= nr_regs ||
  66             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  67                 return -ENOENT;
  68
  69         if (copy_to_user(uaddr, ((u32 *)regs) + off, KVM_REG_SIZE(reg->id)))
  70                 return -EFAULT;
  71
  72         return 0;
  73 }
  74
  75 static int set_core_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
  76 {
  77         __u32 __user *uaddr = (__u32 __user *)(unsigned long)reg->addr;
  78         struct kvm_regs *regs = vcpu_gp_regs(vcpu);
  79         int nr_regs = sizeof(*regs) / sizeof(__u32);
  80         __uint128_t tmp;
  81         void *valp = &tmp;
  82         u64 off;
  83         int err = 0;
  84
  85         /* Our ID is an index into the kvm_regs struct. */
  86         off = core_reg_offset_from_id(reg->id);
  87         if (off >= nr_regs ||
  88             (off + (KVM_REG_SIZE(reg->id) / sizeof(__u32))) >= nr_regs)
  89                 return -ENOENT;
  90
  91         if (KVM_REG_SIZE(reg->id) > sizeof(tmp))
  92                 return -EINVAL;
  93
  94         if (copy_from_user(valp, uaddr, KVM_REG_SIZE(reg->id))) {
  95                 err = -EFAULT;
  96                 goto out;
  97         }
  98
  99         if (off == KVM_REG_ARM_CORE_REG(regs.pstate)) {
 100                 u32 mode = (*(u32 *)valp) & COMPAT_PSR_MODE_MASK;
 101                 switch (mode) {
 102                 case COMPAT_PSR_MODE_USR:
 103                 case COMPAT_PSR_MODE_FIQ:
 104                 case COMPAT_PSR_MODE_IRQ:
 105                 case COMPAT_PSR_MODE_SVC:
 106                 case COMPAT_PSR_MODE_ABT:
 107                 case COMPAT_PSR_MODE_UND:
 108                 case PSR_MODE_EL0t:
 109                 case PSR_MODE_EL1t:
 110                 case PSR_MODE_EL1h:
 111                         break;
 112                 default:
 113                         err = -EINVAL;
 114                         goto out;
 115                 }
 116         }
 117
 118         memcpy((u32 *)regs + off, valp, KVM_REG_SIZE(reg->id));
 119 out:
 120         return err;
 121 }
 122
 123 int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 124 {
 125         return -EINVAL;
 126 }
 127
 128 int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
 129 {
 130         return -EINVAL;
 131 }
 132
 133 static unsigned long num_core_regs(void)
 134 {
 135         return sizeof(struct kvm_regs) / sizeof(__u32);
 136 }
 137
 138 /**
 139  * kvm_arm_num_regs - how many registers do we present via KVM_GET_ONE_REG
 140  *
 141  * This is for all registers.
 142  */
 143 unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu)
 144 {
 145         return num_core_regs() + kvm_arm_num_sys_reg_descs(vcpu);
 146 }
 147
 148 /**
 149  * kvm_arm_copy_reg_indices - get indices of all registers.
 150  *
 151  * We do core registers right here, then we apppend system regs.
 152  */
 153 int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
 154 {
 155         unsigned int i;
 156         const u64 core_reg = KVM_REG_ARM64 | KVM_REG_SIZE_U64 | KVM_REG_ARM_CORE;
 157
 158         for (i = 0; i < sizeof(struct kvm_regs) / sizeof(__u32); i++) {
 159                 if (put_user(core_reg | i, uindices))
 160                         return -EFAULT;
 161                 uindices++;
 162         }
 163
 164         return kvm_arm_copy_sys_reg_indices(vcpu, uindices);
 165 }
 166
 167 int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 168 {
 169         /* We currently use nothing arch-specific in upper 32 bits */
 170         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 171                 return -EINVAL;
 172
 173         /* Register group 16 means we want a core register. */
 174         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 175                 return get_core_reg(vcpu, reg);
 176
 177         return kvm_arm_sys_reg_get_reg(vcpu, reg);
 178 }
 179
 180 int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
 181 {
 182         /* We currently use nothing arch-specific in upper 32 bits */
 183         if ((reg->id & ~KVM_REG_SIZE_MASK) >> 32 != KVM_REG_ARM64 >> 32)
 184                 return -EINVAL;
 185
 186         /* Register group 16 means we set a core register. */
 187         if ((reg->id & KVM_REG_ARM_COPROC_MASK) == KVM_REG_ARM_CORE)
 188                 return set_core_reg(vcpu, reg);
 189
 190         return kvm_arm_sys_reg_set_reg(vcpu, reg);
 191 }
 192
 193 int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
 194                                   struct kvm_sregs *sregs)
 195 {
 196         return -EINVAL;
 197 }
 198
 199 int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 200                                   struct kvm_sregs *sregs)
 201 {
 202         return -EINVAL;
 203 }
 204
 205 int __attribute_const__ kvm_target_cpu(void)
 206 {
 207         unsigned long implementor = read_cpuid_implementor();
 208         unsigned long part_number = read_cpuid_part_number();
 209
 210         if (implementor != ARM_CPU_IMP_ARM)
 211                 return -EINVAL;
 212
 213         switch (part_number) {
 214         case ARM_CPU_PART_AEM_V8:
 215                 return KVM_ARM_TARGET_AEM_V8;
 216         case ARM_CPU_PART_FOUNDATION:
 217                 return KVM_ARM_TARGET_FOUNDATION_V8;
 218         case ARM_CPU_PART_CORTEX_A57:
 219                 /* Currently handled by the generic backend */
 220                 return KVM_ARM_TARGET_CORTEX_A57;
 221         default:
 222                 return -EINVAL;
 223         }
 224 }
 225
 226 int kvm_vcpu_set_target(struct kvm_vcpu *vcpu,
 227                         const struct kvm_vcpu_init *init)
 228 {
 229         unsigned int i;
 230         int phys_target = kvm_target_cpu();
 231
 232         if (init->target != phys_target)
 233                 return -EINVAL;
 234
 235         vcpu->arch.target = phys_target;
 236         bitmap_zero(vcpu->arch.features, KVM_VCPU_MAX_FEATURES);
 237
 238         /* -ENOENT for unknown features, -EINVAL for invalid combinations. */
 239         for (i = 0; i < sizeof(init->features) * 8; i++) {
 240                 if (init->features[i / 32] & (1 << (i % 32))) {
 241                         if (i >= KVM_VCPU_MAX_FEATURES)
 242                                 return -ENOENT;
 243                         set_bit(i, vcpu->arch.features);
 244                 }
 245         }
 246
 247         /* Now we know what it is, we can reset it. */
 248         return kvm_reset_vcpu(vcpu);
 249 }
 250
 251 int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 252 {
 253         return -EINVAL;
 254 }
 255
 256 int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 257 {
 258         return -EINVAL;
 259 }
 260
 261 int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
 262                                   struct kvm_translation *tr)
 263 {
 264         return -EINVAL;
 265 }