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 __hyp_sve_save_guest(struct kvm_vcpu *vcpu) 27 { 28 __vcpu_sys_reg(vcpu, ZCR_EL1) = read_sysreg_el1(SYS_ZCR); 29 /* 30 * On saving/restoring guest sve state, always use the maximum VL for 31 * the guest. The layout of the data when saving the sve state depends 32 * on the VL, so use a consistent (i.e., the maximum) guest VL. 33 */ 34 sve_cond_update_zcr_vq(vcpu_sve_max_vq(vcpu) - 1, SYS_ZCR_EL2); 35 __sve_save_state(vcpu_sve_pffr(vcpu), &vcpu->arch.ctxt.fp_regs.fpsr, true); 36 write_sysreg_s(sve_vq_from_vl(kvm_host_sve_max_vl) - 1, SYS_ZCR_EL2); 37 } 38 39 static void __hyp_sve_restore_host(void) 40 { 41 struct cpu_sve_state *sve_state = *host_data_ptr(sve_state); 42 43 /* 44 * On saving/restoring host sve state, always use the maximum VL for 45 * the host. The layout of the data when saving the sve state depends 46 * on the VL, so use a consistent (i.e., the maximum) host VL. 47 * 48 * Note that this constrains the PE to the maximum shared VL 49 * that was discovered, if we wish to use larger VLs this will 50 * need to be revisited. 51 */ 52 write_sysreg_s(sve_vq_from_vl(kvm_host_sve_max_vl) - 1, SYS_ZCR_EL2); 53 __sve_restore_state(sve_state->sve_regs + sve_ffr_offset(kvm_host_sve_max_vl), 54 &sve_state->fpsr, 55 true); 56 write_sysreg_el1(sve_state->zcr_el1, SYS_ZCR); 57 } 58 59 static void fpsimd_sve_flush(void) 60 { 61 *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; 62 } 63 64 static void fpsimd_sve_sync(struct kvm_vcpu *vcpu) 65 { 66 bool has_fpmr; 67 68 if (!guest_owns_fp_regs()) 69 return; 70 71 cpacr_clear_set(0, CPACR_ELx_FPEN | CPACR_ELx_ZEN); 72 isb(); 73 74 if (vcpu_has_sve(vcpu)) 75 __hyp_sve_save_guest(vcpu); 76 else 77 __fpsimd_save_state(&vcpu->arch.ctxt.fp_regs); 78 79 has_fpmr = kvm_has_fpmr(kern_hyp_va(vcpu->kvm)); 80 if (has_fpmr) 81 __vcpu_sys_reg(vcpu, FPMR) = read_sysreg_s(SYS_FPMR); 82 83 if (system_supports_sve()) 84 __hyp_sve_restore_host(); 85 else 86 __fpsimd_restore_state(*host_data_ptr(fpsimd_state)); 87 88 if (has_fpmr) 89 write_sysreg_s(*host_data_ptr(fpmr), SYS_FPMR); 90 91 *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; 92 } 93 94 static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) 95 { 96 struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; 97 98 fpsimd_sve_flush(); 99 100 hyp_vcpu->vcpu.arch.ctxt = host_vcpu->arch.ctxt; 101 102 hyp_vcpu->vcpu.arch.sve_state = kern_hyp_va(host_vcpu->arch.sve_state); 103 /* Limit guest vector length to the maximum supported by the host. */ 104 hyp_vcpu->vcpu.arch.sve_max_vl = min(host_vcpu->arch.sve_max_vl, kvm_host_sve_max_vl); 105 106 hyp_vcpu->vcpu.arch.hw_mmu = host_vcpu->arch.hw_mmu; 107 108 hyp_vcpu->vcpu.arch.hcr_el2 = host_vcpu->arch.hcr_el2; 109 hyp_vcpu->vcpu.arch.mdcr_el2 = host_vcpu->arch.mdcr_el2; 110 111 hyp_vcpu->vcpu.arch.iflags = host_vcpu->arch.iflags; 112 113 hyp_vcpu->vcpu.arch.debug_ptr = kern_hyp_va(host_vcpu->arch.debug_ptr); 114 115 hyp_vcpu->vcpu.arch.vsesr_el2 = host_vcpu->arch.vsesr_el2; 116 117 hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3; 118 } 119 120 static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) 121 { 122 struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; 123 struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3; 124 struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3; 125 unsigned int i; 126 127 fpsimd_sve_sync(&hyp_vcpu->vcpu); 128 129 host_vcpu->arch.ctxt = hyp_vcpu->vcpu.arch.ctxt; 130 131 host_vcpu->arch.hcr_el2 = hyp_vcpu->vcpu.arch.hcr_el2; 132 133 host_vcpu->arch.fault = hyp_vcpu->vcpu.arch.fault; 134 135 host_vcpu->arch.iflags = hyp_vcpu->vcpu.arch.iflags; 136 137 host_cpu_if->vgic_hcr = hyp_cpu_if->vgic_hcr; 138 for (i = 0; i < hyp_cpu_if->used_lrs; ++i) 139 host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i]; 140 } 141 142 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt) 143 { 144 DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1); 145 int ret; 146 147 host_vcpu = kern_hyp_va(host_vcpu); 148 149 if (unlikely(is_protected_kvm_enabled())) { 150 struct pkvm_hyp_vcpu *hyp_vcpu; 151 struct kvm *host_kvm; 152 153 /* 154 * KVM (and pKVM) doesn't support SME guests for now, and 155 * ensures that SME features aren't enabled in pstate when 156 * loading a vcpu. Therefore, if SME features enabled the host 157 * is misbehaving. 158 */ 159 if (unlikely(system_supports_sme() && read_sysreg_s(SYS_SVCR))) { 160 ret = -EINVAL; 161 goto out; 162 } 163 164 host_kvm = kern_hyp_va(host_vcpu->kvm); 165 hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle, 166 host_vcpu->vcpu_idx); 167 if (!hyp_vcpu) { 168 ret = -EINVAL; 169 goto out; 170 } 171 172 flush_hyp_vcpu(hyp_vcpu); 173 174 ret = __kvm_vcpu_run(&hyp_vcpu->vcpu); 175 176 sync_hyp_vcpu(hyp_vcpu); 177 pkvm_put_hyp_vcpu(hyp_vcpu); 178 } else { 179 /* The host is fully trusted, run its vCPU directly. */ 180 ret = __kvm_vcpu_run(host_vcpu); 181 } 182 183 out: 184 cpu_reg(host_ctxt, 1) = ret; 185 } 186 187 static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt) 188 { 189 DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); 190 191 __kvm_adjust_pc(kern_hyp_va(vcpu)); 192 } 193 194 static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt) 195 { 196 __kvm_flush_vm_context(); 197 } 198 199 static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt) 200 { 201 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 202 DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2); 203 DECLARE_REG(int, level, host_ctxt, 3); 204 205 __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level); 206 } 207 208 static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt) 209 { 210 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 211 DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2); 212 DECLARE_REG(int, level, host_ctxt, 3); 213 214 __kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level); 215 } 216 217 static void 218 handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt) 219 { 220 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 221 DECLARE_REG(phys_addr_t, start, host_ctxt, 2); 222 DECLARE_REG(unsigned long, pages, host_ctxt, 3); 223 224 __kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages); 225 } 226 227 static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt) 228 { 229 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 230 231 __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); 232 } 233 234 static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt) 235 { 236 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 237 238 __kvm_flush_cpu_context(kern_hyp_va(mmu)); 239 } 240 241 static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt) 242 { 243 __kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1)); 244 } 245 246 static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt) 247 { 248 u64 tmp; 249 250 tmp = read_sysreg_el2(SYS_SCTLR); 251 tmp |= SCTLR_ELx_DSSBS; 252 write_sysreg_el2(tmp, SYS_SCTLR); 253 } 254 255 static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt) 256 { 257 cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config(); 258 } 259 260 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt) 261 { 262 __vgic_v3_init_lrs(); 263 } 264 265 static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt) 266 { 267 cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2(); 268 } 269 270 static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt) 271 { 272 DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); 273 274 __vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if)); 275 } 276 277 static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt) 278 { 279 DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); 280 281 __vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if)); 282 } 283 284 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt) 285 { 286 DECLARE_REG(phys_addr_t, phys, host_ctxt, 1); 287 DECLARE_REG(unsigned long, size, host_ctxt, 2); 288 DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3); 289 DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4); 290 DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5); 291 292 /* 293 * __pkvm_init() will return only if an error occurred, otherwise it 294 * will tail-call in __pkvm_init_finalise() which will have to deal 295 * with the host context directly. 296 */ 297 cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base, 298 hyp_va_bits); 299 } 300 301 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt) 302 { 303 DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1); 304 305 cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot); 306 } 307 308 static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt) 309 { 310 DECLARE_REG(u64, pfn, host_ctxt, 1); 311 312 cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn); 313 } 314 315 static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt) 316 { 317 DECLARE_REG(u64, pfn, host_ctxt, 1); 318 319 cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn); 320 } 321 322 static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt) 323 { 324 DECLARE_REG(phys_addr_t, phys, host_ctxt, 1); 325 DECLARE_REG(size_t, size, host_ctxt, 2); 326 DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3); 327 328 /* 329 * __pkvm_create_private_mapping() populates a pointer with the 330 * hypervisor start address of the allocation. 331 * 332 * However, handle___pkvm_create_private_mapping() hypercall crosses the 333 * EL1/EL2 boundary so the pointer would not be valid in this context. 334 * 335 * Instead pass the allocation address as the return value (or return 336 * ERR_PTR() on failure). 337 */ 338 unsigned long haddr; 339 int err = __pkvm_create_private_mapping(phys, size, prot, &haddr); 340 341 if (err) 342 haddr = (unsigned long)ERR_PTR(err); 343 344 cpu_reg(host_ctxt, 1) = haddr; 345 } 346 347 static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt) 348 { 349 cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize(); 350 } 351 352 static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt) 353 { 354 DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); 355 356 __pkvm_vcpu_init_traps(kern_hyp_va(vcpu)); 357 } 358 359 static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt) 360 { 361 DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1); 362 DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2); 363 DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3); 364 365 host_kvm = kern_hyp_va(host_kvm); 366 cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva); 367 } 368 369 static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt) 370 { 371 DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); 372 DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2); 373 DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3); 374 375 host_vcpu = kern_hyp_va(host_vcpu); 376 cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva); 377 } 378 379 static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt) 380 { 381 DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); 382 383 cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle); 384 } 385 386 typedef void (*hcall_t)(struct kvm_cpu_context *); 387 388 #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x 389 390 static const hcall_t host_hcall[] = { 391 /* ___kvm_hyp_init */ 392 HANDLE_FUNC(__kvm_get_mdcr_el2), 393 HANDLE_FUNC(__pkvm_init), 394 HANDLE_FUNC(__pkvm_create_private_mapping), 395 HANDLE_FUNC(__pkvm_cpu_set_vector), 396 HANDLE_FUNC(__kvm_enable_ssbs), 397 HANDLE_FUNC(__vgic_v3_init_lrs), 398 HANDLE_FUNC(__vgic_v3_get_gic_config), 399 HANDLE_FUNC(__pkvm_prot_finalize), 400 401 HANDLE_FUNC(__pkvm_host_share_hyp), 402 HANDLE_FUNC(__pkvm_host_unshare_hyp), 403 HANDLE_FUNC(__kvm_adjust_pc), 404 HANDLE_FUNC(__kvm_vcpu_run), 405 HANDLE_FUNC(__kvm_flush_vm_context), 406 HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa), 407 HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh), 408 HANDLE_FUNC(__kvm_tlb_flush_vmid), 409 HANDLE_FUNC(__kvm_tlb_flush_vmid_range), 410 HANDLE_FUNC(__kvm_flush_cpu_context), 411 HANDLE_FUNC(__kvm_timer_set_cntvoff), 412 HANDLE_FUNC(__vgic_v3_save_vmcr_aprs), 413 HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs), 414 HANDLE_FUNC(__pkvm_vcpu_init_traps), 415 HANDLE_FUNC(__pkvm_init_vm), 416 HANDLE_FUNC(__pkvm_init_vcpu), 417 HANDLE_FUNC(__pkvm_teardown_vm), 418 }; 419 420 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) 421 { 422 DECLARE_REG(unsigned long, id, host_ctxt, 0); 423 unsigned long hcall_min = 0; 424 hcall_t hfn; 425 426 /* 427 * If pKVM has been initialised then reject any calls to the 428 * early "privileged" hypercalls. Note that we cannot reject 429 * calls to __pkvm_prot_finalize for two reasons: (1) The static 430 * key used to determine initialisation must be toggled prior to 431 * finalisation and (2) finalisation is performed on a per-CPU 432 * basis. This is all fine, however, since __pkvm_prot_finalize 433 * returns -EPERM after the first call for a given CPU. 434 */ 435 if (static_branch_unlikely(&kvm_protected_mode_initialized)) 436 hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize; 437 438 id &= ~ARM_SMCCC_CALL_HINTS; 439 id -= KVM_HOST_SMCCC_ID(0); 440 441 if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall))) 442 goto inval; 443 444 hfn = host_hcall[id]; 445 if (unlikely(!hfn)) 446 goto inval; 447 448 cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS; 449 hfn(host_ctxt); 450 451 return; 452 inval: 453 cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED; 454 } 455 456 static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt) 457 { 458 __kvm_hyp_host_forward_smc(host_ctxt); 459 } 460 461 static void handle_host_smc(struct kvm_cpu_context *host_ctxt) 462 { 463 DECLARE_REG(u64, func_id, host_ctxt, 0); 464 bool handled; 465 466 func_id &= ~ARM_SMCCC_CALL_HINTS; 467 468 handled = kvm_host_psci_handler(host_ctxt, func_id); 469 if (!handled) 470 handled = kvm_host_ffa_handler(host_ctxt, func_id); 471 if (!handled) 472 default_host_smc_handler(host_ctxt); 473 474 /* SMC was trapped, move ELR past the current PC. */ 475 kvm_skip_host_instr(); 476 } 477 478 void handle_trap(struct kvm_cpu_context *host_ctxt) 479 { 480 u64 esr = read_sysreg_el2(SYS_ESR); 481 482 switch (ESR_ELx_EC(esr)) { 483 case ESR_ELx_EC_HVC64: 484 handle_host_hcall(host_ctxt); 485 break; 486 case ESR_ELx_EC_SMC64: 487 handle_host_smc(host_ctxt); 488 break; 489 case ESR_ELx_EC_SVE: 490 cpacr_clear_set(0, CPACR_ELx_ZEN); 491 isb(); 492 sve_cond_update_zcr_vq(sve_vq_from_vl(kvm_host_sve_max_vl) - 1, 493 SYS_ZCR_EL2); 494 break; 495 case ESR_ELx_EC_IABT_LOW: 496 case ESR_ELx_EC_DABT_LOW: 497 handle_host_mem_abort(host_ctxt); 498 break; 499 default: 500 BUG(); 501 } 502 } 503