arch/arm64/kvm/hyp/nvhe/hyp-main.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2020 - Google Inc
   4  * Author: Andrew Scull <ascull@google.com>
   5  */
   6
   7 #include <hyp/adjust_pc.h>
   8
   9 #include <asm/pgtable-types.h>
  10 #include <asm/kvm_asm.h>
  11 #include <asm/kvm_emulate.h>
  12 #include <asm/kvm_host.h>
  13 #include <asm/kvm_hyp.h>
  14 #include <asm/kvm_mmu.h>
  15
  16 #include <nvhe/ffa.h>
  17 #include <nvhe/mem_protect.h>
  18 #include <nvhe/mm.h>
  19 #include <nvhe/pkvm.h>
  20 #include <nvhe/trap_handler.h>
  21
  22 DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
  23
  24 void __kvm_hyp_host_forward_smc(struct kvm_cpu_context *host_ctxt);
  25
  26 static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
  27 {
  28         struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
  29
  30         hyp_vcpu->vcpu.arch.ctxt        = host_vcpu->arch.ctxt;
  31
  32         hyp_vcpu->vcpu.arch.sve_state   = kern_hyp_va(host_vcpu->arch.sve_state);
  33         hyp_vcpu->vcpu.arch.sve_max_vl  = host_vcpu->arch.sve_max_vl;
  34
  35         hyp_vcpu->vcpu.arch.hw_mmu      = host_vcpu->arch.hw_mmu;
  36
  37         hyp_vcpu->vcpu.arch.hcr_el2     = host_vcpu->arch.hcr_el2;
  38         hyp_vcpu->vcpu.arch.mdcr_el2    = host_vcpu->arch.mdcr_el2;
  39         hyp_vcpu->vcpu.arch.cptr_el2    = host_vcpu->arch.cptr_el2;
  40
  41         hyp_vcpu->vcpu.arch.iflags      = host_vcpu->arch.iflags;
  42         hyp_vcpu->vcpu.arch.fp_state    = host_vcpu->arch.fp_state;
  43
  44         hyp_vcpu->vcpu.arch.debug_ptr   = kern_hyp_va(host_vcpu->arch.debug_ptr);
  45         hyp_vcpu->vcpu.arch.host_fpsimd_state = host_vcpu->arch.host_fpsimd_state;
  46
  47         hyp_vcpu->vcpu.arch.vsesr_el2   = host_vcpu->arch.vsesr_el2;
  48
  49         hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3;
  50 }
  51
  52 static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
  53 {
  54         struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu;
  55         struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3;
  56         struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3;
  57         unsigned int i;
  58
  59         host_vcpu->arch.ctxt            = hyp_vcpu->vcpu.arch.ctxt;
  60
  61         host_vcpu->arch.hcr_el2         = hyp_vcpu->vcpu.arch.hcr_el2;
  62         host_vcpu->arch.cptr_el2        = hyp_vcpu->vcpu.arch.cptr_el2;
  63
  64         host_vcpu->arch.fault           = hyp_vcpu->vcpu.arch.fault;
  65
  66         host_vcpu->arch.iflags          = hyp_vcpu->vcpu.arch.iflags;
  67         host_vcpu->arch.fp_state        = hyp_vcpu->vcpu.arch.fp_state;
  68
  69         host_cpu_if->vgic_hcr           = hyp_cpu_if->vgic_hcr;
  70         for (i = 0; i < hyp_cpu_if->used_lrs; ++i)
  71                 host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i];
  72 }
  73
  74 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt)
  75 {
  76         DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1);
  77         int ret;
  78
  79         host_vcpu = kern_hyp_va(host_vcpu);
  80
  81         if (unlikely(is_protected_kvm_enabled())) {
  82                 struct pkvm_hyp_vcpu *hyp_vcpu;
  83                 struct kvm *host_kvm;
  84
  85                 host_kvm = kern_hyp_va(host_vcpu->kvm);
  86                 hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle,
  87                                               host_vcpu->vcpu_idx);
  88                 if (!hyp_vcpu) {
  89                         ret = -EINVAL;
  90                         goto out;
  91                 }
  92
  93                 flush_hyp_vcpu(hyp_vcpu);
  94
  95                 ret = __kvm_vcpu_run(&hyp_vcpu->vcpu);
  96
  97                 sync_hyp_vcpu(hyp_vcpu);
  98                 pkvm_put_hyp_vcpu(hyp_vcpu);
  99         } else {
 100                 /* The host is fully trusted, run its vCPU directly. */
 101                 ret = __kvm_vcpu_run(host_vcpu);
 102         }
 103
 104 out:
 105         cpu_reg(host_ctxt, 1) =  ret;
 106 }
 107
 108 static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt)
 109 {
 110         DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
 111
 112         __kvm_adjust_pc(kern_hyp_va(vcpu));
 113 }
 114
 115 static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt)
 116 {
 117         __kvm_flush_vm_context();
 118 }
 119
 120 static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt)
 121 {
 122         DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
 123         DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
 124         DECLARE_REG(int, level, host_ctxt, 3);
 125
 126         __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level);
 127 }
 128
 129 static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt)
 130 {
 131         DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
 132         DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2);
 133         DECLARE_REG(int, level, host_ctxt, 3);
 134
 135         __kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level);
 136 }
 137
 138 static void
 139 handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt)
 140 {
 141         DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
 142         DECLARE_REG(phys_addr_t, start, host_ctxt, 2);
 143         DECLARE_REG(unsigned long, pages, host_ctxt, 3);
 144
 145         __kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages);
 146 }
 147
 148 static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt)
 149 {
 150         DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
 151
 152         __kvm_tlb_flush_vmid(kern_hyp_va(mmu));
 153 }
 154
 155 static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt)
 156 {
 157         DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1);
 158
 159         __kvm_flush_cpu_context(kern_hyp_va(mmu));
 160 }
 161
 162 static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt)
 163 {
 164         __kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1));
 165 }
 166
 167 static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt)
 168 {
 169         u64 tmp;
 170
 171         tmp = read_sysreg_el2(SYS_SCTLR);
 172         tmp |= SCTLR_ELx_DSSBS;
 173         write_sysreg_el2(tmp, SYS_SCTLR);
 174 }
 175
 176 static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt)
 177 {
 178         cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config();
 179 }
 180
 181 static void handle___vgic_v3_read_vmcr(struct kvm_cpu_context *host_ctxt)
 182 {
 183         cpu_reg(host_ctxt, 1) = __vgic_v3_read_vmcr();
 184 }
 185
 186 static void handle___vgic_v3_write_vmcr(struct kvm_cpu_context *host_ctxt)
 187 {
 188         __vgic_v3_write_vmcr(cpu_reg(host_ctxt, 1));
 189 }
 190
 191 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt)
 192 {
 193         __vgic_v3_init_lrs();
 194 }
 195
 196 static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt)
 197 {
 198         cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2();
 199 }
 200
 201 static void handle___vgic_v3_save_aprs(struct kvm_cpu_context *host_ctxt)
 202 {
 203         DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
 204
 205         __vgic_v3_save_aprs(kern_hyp_va(cpu_if));
 206 }
 207
 208 static void handle___vgic_v3_restore_aprs(struct kvm_cpu_context *host_ctxt)
 209 {
 210         DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1);
 211
 212         __vgic_v3_restore_aprs(kern_hyp_va(cpu_if));
 213 }
 214
 215 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt)
 216 {
 217         DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
 218         DECLARE_REG(unsigned long, size, host_ctxt, 2);
 219         DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3);
 220         DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4);
 221         DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5);
 222
 223         /*
 224          * __pkvm_init() will return only if an error occurred, otherwise it
 225          * will tail-call in __pkvm_init_finalise() which will have to deal
 226          * with the host context directly.
 227          */
 228         cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base,
 229                                             hyp_va_bits);
 230 }
 231
 232 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt)
 233 {
 234         DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1);
 235
 236         cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot);
 237 }
 238
 239 static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt)
 240 {
 241         DECLARE_REG(u64, pfn, host_ctxt, 1);
 242
 243         cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn);
 244 }
 245
 246 static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt)
 247 {
 248         DECLARE_REG(u64, pfn, host_ctxt, 1);
 249
 250         cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn);
 251 }
 252
 253 static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt)
 254 {
 255         DECLARE_REG(phys_addr_t, phys, host_ctxt, 1);
 256         DECLARE_REG(size_t, size, host_ctxt, 2);
 257         DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3);
 258
 259         /*
 260          * __pkvm_create_private_mapping() populates a pointer with the
 261          * hypervisor start address of the allocation.
 262          *
 263          * However, handle___pkvm_create_private_mapping() hypercall crosses the
 264          * EL1/EL2 boundary so the pointer would not be valid in this context.
 265          *
 266          * Instead pass the allocation address as the return value (or return
 267          * ERR_PTR() on failure).
 268          */
 269         unsigned long haddr;
 270         int err = __pkvm_create_private_mapping(phys, size, prot, &haddr);
 271
 272         if (err)
 273                 haddr = (unsigned long)ERR_PTR(err);
 274
 275         cpu_reg(host_ctxt, 1) = haddr;
 276 }
 277
 278 static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt)
 279 {
 280         cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize();
 281 }
 282
 283 static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt)
 284 {
 285         DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1);
 286
 287         __pkvm_vcpu_init_traps(kern_hyp_va(vcpu));
 288 }
 289
 290 static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt)
 291 {
 292         DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
 293         DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2);
 294         DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3);
 295
 296         host_kvm = kern_hyp_va(host_kvm);
 297         cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva);
 298 }
 299
 300 static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt)
 301 {
 302         DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
 303         DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2);
 304         DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3);
 305
 306         host_vcpu = kern_hyp_va(host_vcpu);
 307         cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva);
 308 }
 309
 310 static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt)
 311 {
 312         DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1);
 313
 314         cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle);
 315 }
 316
 317 typedef void (*hcall_t)(struct kvm_cpu_context *);
 318
 319 #define HANDLE_FUNC(x)  [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
 320
 321 static const hcall_t host_hcall[] = {
 322         /* ___kvm_hyp_init */
 323         HANDLE_FUNC(__kvm_get_mdcr_el2),
 324         HANDLE_FUNC(__pkvm_init),
 325         HANDLE_FUNC(__pkvm_create_private_mapping),
 326         HANDLE_FUNC(__pkvm_cpu_set_vector),
 327         HANDLE_FUNC(__kvm_enable_ssbs),
 328         HANDLE_FUNC(__vgic_v3_init_lrs),
 329         HANDLE_FUNC(__vgic_v3_get_gic_config),
 330         HANDLE_FUNC(__pkvm_prot_finalize),
 331
 332         HANDLE_FUNC(__pkvm_host_share_hyp),
 333         HANDLE_FUNC(__pkvm_host_unshare_hyp),
 334         HANDLE_FUNC(__kvm_adjust_pc),
 335         HANDLE_FUNC(__kvm_vcpu_run),
 336         HANDLE_FUNC(__kvm_flush_vm_context),
 337         HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa),
 338         HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh),
 339         HANDLE_FUNC(__kvm_tlb_flush_vmid),
 340         HANDLE_FUNC(__kvm_tlb_flush_vmid_range),
 341         HANDLE_FUNC(__kvm_flush_cpu_context),
 342         HANDLE_FUNC(__kvm_timer_set_cntvoff),
 343         HANDLE_FUNC(__vgic_v3_read_vmcr),
 344         HANDLE_FUNC(__vgic_v3_write_vmcr),
 345         HANDLE_FUNC(__vgic_v3_save_aprs),
 346         HANDLE_FUNC(__vgic_v3_restore_aprs),
 347         HANDLE_FUNC(__pkvm_vcpu_init_traps),
 348         HANDLE_FUNC(__pkvm_init_vm),
 349         HANDLE_FUNC(__pkvm_init_vcpu),
 350         HANDLE_FUNC(__pkvm_teardown_vm),
 351 };
 352
 353 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
 354 {
 355         DECLARE_REG(unsigned long, id, host_ctxt, 0);
 356         unsigned long hcall_min = 0;
 357         hcall_t hfn;
 358
 359         /*
 360          * If pKVM has been initialised then reject any calls to the
 361          * early "privileged" hypercalls. Note that we cannot reject
 362          * calls to __pkvm_prot_finalize for two reasons: (1) The static
 363          * key used to determine initialisation must be toggled prior to
 364          * finalisation and (2) finalisation is performed on a per-CPU
 365          * basis. This is all fine, however, since __pkvm_prot_finalize
 366          * returns -EPERM after the first call for a given CPU.
 367          */
 368         if (static_branch_unlikely(&kvm_protected_mode_initialized))
 369                 hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize;
 370
 371         id -= KVM_HOST_SMCCC_ID(0);
 372
 373         if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall)))
 374                 goto inval;
 375
 376         hfn = host_hcall[id];
 377         if (unlikely(!hfn))
 378                 goto inval;
 379
 380         cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS;
 381         hfn(host_ctxt);
 382
 383         return;
 384 inval:
 385         cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED;
 386 }
 387
 388 static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt)
 389 {
 390         __kvm_hyp_host_forward_smc(host_ctxt);
 391 }
 392
 393 static void handle_host_smc(struct kvm_cpu_context *host_ctxt)
 394 {
 395         bool handled;
 396
 397         handled = kvm_host_psci_handler(host_ctxt);
 398         if (!handled)
 399                 handled = kvm_host_ffa_handler(host_ctxt);
 400         if (!handled)
 401                 default_host_smc_handler(host_ctxt);
 402
 403         /* SMC was trapped, move ELR past the current PC. */
 404         kvm_skip_host_instr();
 405 }
 406
 407 void handle_trap(struct kvm_cpu_context *host_ctxt)
 408 {
 409         u64 esr = read_sysreg_el2(SYS_ESR);
 410
 411         switch (ESR_ELx_EC(esr)) {
 412         case ESR_ELx_EC_HVC64:
 413                 handle_host_hcall(host_ctxt);
 414                 break;
 415         case ESR_ELx_EC_SMC64:
 416                 handle_host_smc(host_ctxt);
 417                 break;
 418         case ESR_ELx_EC_SVE:
 419                 if (has_hvhe())
 420                         sysreg_clear_set(cpacr_el1, 0, (CPACR_EL1_ZEN_EL1EN |
 421                                                         CPACR_EL1_ZEN_EL0EN));
 422                 else
 423                         sysreg_clear_set(cptr_el2, CPTR_EL2_TZ, 0);
 424                 isb();
 425                 sve_cond_update_zcr_vq(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2);
 426                 break;
 427         case ESR_ELx_EC_IABT_LOW:
 428         case ESR_ELx_EC_DABT_LOW:
 429                 handle_host_mem_abort(host_ctxt);
 430                 break;
 431         default:
 432                 BUG();
 433         }
 434 }