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(ZCR_ELx_LEN_MASK, 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 * Setting ZCR_EL2 to ZCR_ELx_LEN_MASK sets the effective length 49 * supported by the system (or limited at EL3). 50 */ 51 write_sysreg_s(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2); 52 __sve_restore_state(sve_state->sve_regs + sve_ffr_offset(kvm_host_sve_max_vl), 53 &sve_state->fpsr, 54 true); 55 write_sysreg_el1(sve_state->zcr_el1, SYS_ZCR); 56 } 57 58 static void fpsimd_sve_flush(void) 59 { 60 *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; 61 } 62 63 static void fpsimd_sve_sync(struct kvm_vcpu *vcpu) 64 { 65 if (!guest_owns_fp_regs()) 66 return; 67 68 cpacr_clear_set(0, CPACR_ELx_FPEN | CPACR_ELx_ZEN); 69 isb(); 70 71 if (vcpu_has_sve(vcpu)) 72 __hyp_sve_save_guest(vcpu); 73 else 74 __fpsimd_save_state(&vcpu->arch.ctxt.fp_regs); 75 76 if (system_supports_sve()) 77 __hyp_sve_restore_host(); 78 else 79 __fpsimd_restore_state(*host_data_ptr(fpsimd_state)); 80 81 *host_data_ptr(fp_owner) = FP_STATE_HOST_OWNED; 82 } 83 84 static void flush_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) 85 { 86 struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; 87 88 fpsimd_sve_flush(); 89 90 hyp_vcpu->vcpu.arch.ctxt = host_vcpu->arch.ctxt; 91 92 hyp_vcpu->vcpu.arch.sve_state = kern_hyp_va(host_vcpu->arch.sve_state); 93 /* Limit guest vector length to the maximum supported by the host. */ 94 hyp_vcpu->vcpu.arch.sve_max_vl = min(host_vcpu->arch.sve_max_vl, kvm_host_sve_max_vl); 95 96 hyp_vcpu->vcpu.arch.hw_mmu = host_vcpu->arch.hw_mmu; 97 98 hyp_vcpu->vcpu.arch.hcr_el2 = host_vcpu->arch.hcr_el2; 99 hyp_vcpu->vcpu.arch.mdcr_el2 = host_vcpu->arch.mdcr_el2; 100 101 hyp_vcpu->vcpu.arch.iflags = host_vcpu->arch.iflags; 102 103 hyp_vcpu->vcpu.arch.debug_ptr = kern_hyp_va(host_vcpu->arch.debug_ptr); 104 105 hyp_vcpu->vcpu.arch.vsesr_el2 = host_vcpu->arch.vsesr_el2; 106 107 hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3 = host_vcpu->arch.vgic_cpu.vgic_v3; 108 } 109 110 static void sync_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu) 111 { 112 struct kvm_vcpu *host_vcpu = hyp_vcpu->host_vcpu; 113 struct vgic_v3_cpu_if *hyp_cpu_if = &hyp_vcpu->vcpu.arch.vgic_cpu.vgic_v3; 114 struct vgic_v3_cpu_if *host_cpu_if = &host_vcpu->arch.vgic_cpu.vgic_v3; 115 unsigned int i; 116 117 fpsimd_sve_sync(&hyp_vcpu->vcpu); 118 119 host_vcpu->arch.ctxt = hyp_vcpu->vcpu.arch.ctxt; 120 121 host_vcpu->arch.hcr_el2 = hyp_vcpu->vcpu.arch.hcr_el2; 122 123 host_vcpu->arch.fault = hyp_vcpu->vcpu.arch.fault; 124 125 host_vcpu->arch.iflags = hyp_vcpu->vcpu.arch.iflags; 126 127 host_cpu_if->vgic_hcr = hyp_cpu_if->vgic_hcr; 128 for (i = 0; i < hyp_cpu_if->used_lrs; ++i) 129 host_cpu_if->vgic_lr[i] = hyp_cpu_if->vgic_lr[i]; 130 } 131 132 static void handle___kvm_vcpu_run(struct kvm_cpu_context *host_ctxt) 133 { 134 DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 1); 135 int ret; 136 137 host_vcpu = kern_hyp_va(host_vcpu); 138 139 if (unlikely(is_protected_kvm_enabled())) { 140 struct pkvm_hyp_vcpu *hyp_vcpu; 141 struct kvm *host_kvm; 142 143 /* 144 * KVM (and pKVM) doesn't support SME guests for now, and 145 * ensures that SME features aren't enabled in pstate when 146 * loading a vcpu. Therefore, if SME features enabled the host 147 * is misbehaving. 148 */ 149 if (unlikely(system_supports_sme() && read_sysreg_s(SYS_SVCR))) { 150 ret = -EINVAL; 151 goto out; 152 } 153 154 host_kvm = kern_hyp_va(host_vcpu->kvm); 155 hyp_vcpu = pkvm_load_hyp_vcpu(host_kvm->arch.pkvm.handle, 156 host_vcpu->vcpu_idx); 157 if (!hyp_vcpu) { 158 ret = -EINVAL; 159 goto out; 160 } 161 162 flush_hyp_vcpu(hyp_vcpu); 163 164 ret = __kvm_vcpu_run(&hyp_vcpu->vcpu); 165 166 sync_hyp_vcpu(hyp_vcpu); 167 pkvm_put_hyp_vcpu(hyp_vcpu); 168 } else { 169 /* The host is fully trusted, run its vCPU directly. */ 170 ret = __kvm_vcpu_run(host_vcpu); 171 } 172 173 out: 174 cpu_reg(host_ctxt, 1) = ret; 175 } 176 177 static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt) 178 { 179 DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); 180 181 __kvm_adjust_pc(kern_hyp_va(vcpu)); 182 } 183 184 static void handle___kvm_flush_vm_context(struct kvm_cpu_context *host_ctxt) 185 { 186 __kvm_flush_vm_context(); 187 } 188 189 static void handle___kvm_tlb_flush_vmid_ipa(struct kvm_cpu_context *host_ctxt) 190 { 191 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 192 DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2); 193 DECLARE_REG(int, level, host_ctxt, 3); 194 195 __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level); 196 } 197 198 static void handle___kvm_tlb_flush_vmid_ipa_nsh(struct kvm_cpu_context *host_ctxt) 199 { 200 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 201 DECLARE_REG(phys_addr_t, ipa, host_ctxt, 2); 202 DECLARE_REG(int, level, host_ctxt, 3); 203 204 __kvm_tlb_flush_vmid_ipa_nsh(kern_hyp_va(mmu), ipa, level); 205 } 206 207 static void 208 handle___kvm_tlb_flush_vmid_range(struct kvm_cpu_context *host_ctxt) 209 { 210 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 211 DECLARE_REG(phys_addr_t, start, host_ctxt, 2); 212 DECLARE_REG(unsigned long, pages, host_ctxt, 3); 213 214 __kvm_tlb_flush_vmid_range(kern_hyp_va(mmu), start, pages); 215 } 216 217 static void handle___kvm_tlb_flush_vmid(struct kvm_cpu_context *host_ctxt) 218 { 219 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 220 221 __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); 222 } 223 224 static void handle___kvm_flush_cpu_context(struct kvm_cpu_context *host_ctxt) 225 { 226 DECLARE_REG(struct kvm_s2_mmu *, mmu, host_ctxt, 1); 227 228 __kvm_flush_cpu_context(kern_hyp_va(mmu)); 229 } 230 231 static void handle___kvm_timer_set_cntvoff(struct kvm_cpu_context *host_ctxt) 232 { 233 __kvm_timer_set_cntvoff(cpu_reg(host_ctxt, 1)); 234 } 235 236 static void handle___kvm_enable_ssbs(struct kvm_cpu_context *host_ctxt) 237 { 238 u64 tmp; 239 240 tmp = read_sysreg_el2(SYS_SCTLR); 241 tmp |= SCTLR_ELx_DSSBS; 242 write_sysreg_el2(tmp, SYS_SCTLR); 243 } 244 245 static void handle___vgic_v3_get_gic_config(struct kvm_cpu_context *host_ctxt) 246 { 247 cpu_reg(host_ctxt, 1) = __vgic_v3_get_gic_config(); 248 } 249 250 static void handle___vgic_v3_init_lrs(struct kvm_cpu_context *host_ctxt) 251 { 252 __vgic_v3_init_lrs(); 253 } 254 255 static void handle___kvm_get_mdcr_el2(struct kvm_cpu_context *host_ctxt) 256 { 257 cpu_reg(host_ctxt, 1) = __kvm_get_mdcr_el2(); 258 } 259 260 static void handle___vgic_v3_save_vmcr_aprs(struct kvm_cpu_context *host_ctxt) 261 { 262 DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); 263 264 __vgic_v3_save_vmcr_aprs(kern_hyp_va(cpu_if)); 265 } 266 267 static void handle___vgic_v3_restore_vmcr_aprs(struct kvm_cpu_context *host_ctxt) 268 { 269 DECLARE_REG(struct vgic_v3_cpu_if *, cpu_if, host_ctxt, 1); 270 271 __vgic_v3_restore_vmcr_aprs(kern_hyp_va(cpu_if)); 272 } 273 274 static void handle___pkvm_init(struct kvm_cpu_context *host_ctxt) 275 { 276 DECLARE_REG(phys_addr_t, phys, host_ctxt, 1); 277 DECLARE_REG(unsigned long, size, host_ctxt, 2); 278 DECLARE_REG(unsigned long, nr_cpus, host_ctxt, 3); 279 DECLARE_REG(unsigned long *, per_cpu_base, host_ctxt, 4); 280 DECLARE_REG(u32, hyp_va_bits, host_ctxt, 5); 281 282 /* 283 * __pkvm_init() will return only if an error occurred, otherwise it 284 * will tail-call in __pkvm_init_finalise() which will have to deal 285 * with the host context directly. 286 */ 287 cpu_reg(host_ctxt, 1) = __pkvm_init(phys, size, nr_cpus, per_cpu_base, 288 hyp_va_bits); 289 } 290 291 static void handle___pkvm_cpu_set_vector(struct kvm_cpu_context *host_ctxt) 292 { 293 DECLARE_REG(enum arm64_hyp_spectre_vector, slot, host_ctxt, 1); 294 295 cpu_reg(host_ctxt, 1) = pkvm_cpu_set_vector(slot); 296 } 297 298 static void handle___pkvm_host_share_hyp(struct kvm_cpu_context *host_ctxt) 299 { 300 DECLARE_REG(u64, pfn, host_ctxt, 1); 301 302 cpu_reg(host_ctxt, 1) = __pkvm_host_share_hyp(pfn); 303 } 304 305 static void handle___pkvm_host_unshare_hyp(struct kvm_cpu_context *host_ctxt) 306 { 307 DECLARE_REG(u64, pfn, host_ctxt, 1); 308 309 cpu_reg(host_ctxt, 1) = __pkvm_host_unshare_hyp(pfn); 310 } 311 312 static void handle___pkvm_create_private_mapping(struct kvm_cpu_context *host_ctxt) 313 { 314 DECLARE_REG(phys_addr_t, phys, host_ctxt, 1); 315 DECLARE_REG(size_t, size, host_ctxt, 2); 316 DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 3); 317 318 /* 319 * __pkvm_create_private_mapping() populates a pointer with the 320 * hypervisor start address of the allocation. 321 * 322 * However, handle___pkvm_create_private_mapping() hypercall crosses the 323 * EL1/EL2 boundary so the pointer would not be valid in this context. 324 * 325 * Instead pass the allocation address as the return value (or return 326 * ERR_PTR() on failure). 327 */ 328 unsigned long haddr; 329 int err = __pkvm_create_private_mapping(phys, size, prot, &haddr); 330 331 if (err) 332 haddr = (unsigned long)ERR_PTR(err); 333 334 cpu_reg(host_ctxt, 1) = haddr; 335 } 336 337 static void handle___pkvm_prot_finalize(struct kvm_cpu_context *host_ctxt) 338 { 339 cpu_reg(host_ctxt, 1) = __pkvm_prot_finalize(); 340 } 341 342 static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt) 343 { 344 DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); 345 346 __pkvm_vcpu_init_traps(kern_hyp_va(vcpu)); 347 } 348 349 static void handle___pkvm_init_vm(struct kvm_cpu_context *host_ctxt) 350 { 351 DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1); 352 DECLARE_REG(unsigned long, vm_hva, host_ctxt, 2); 353 DECLARE_REG(unsigned long, pgd_hva, host_ctxt, 3); 354 355 host_kvm = kern_hyp_va(host_kvm); 356 cpu_reg(host_ctxt, 1) = __pkvm_init_vm(host_kvm, vm_hva, pgd_hva); 357 } 358 359 static void handle___pkvm_init_vcpu(struct kvm_cpu_context *host_ctxt) 360 { 361 DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); 362 DECLARE_REG(struct kvm_vcpu *, host_vcpu, host_ctxt, 2); 363 DECLARE_REG(unsigned long, vcpu_hva, host_ctxt, 3); 364 365 host_vcpu = kern_hyp_va(host_vcpu); 366 cpu_reg(host_ctxt, 1) = __pkvm_init_vcpu(handle, host_vcpu, vcpu_hva); 367 } 368 369 static void handle___pkvm_teardown_vm(struct kvm_cpu_context *host_ctxt) 370 { 371 DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); 372 373 cpu_reg(host_ctxt, 1) = __pkvm_teardown_vm(handle); 374 } 375 376 typedef void (*hcall_t)(struct kvm_cpu_context *); 377 378 #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x 379 380 static const hcall_t host_hcall[] = { 381 /* ___kvm_hyp_init */ 382 HANDLE_FUNC(__kvm_get_mdcr_el2), 383 HANDLE_FUNC(__pkvm_init), 384 HANDLE_FUNC(__pkvm_create_private_mapping), 385 HANDLE_FUNC(__pkvm_cpu_set_vector), 386 HANDLE_FUNC(__kvm_enable_ssbs), 387 HANDLE_FUNC(__vgic_v3_init_lrs), 388 HANDLE_FUNC(__vgic_v3_get_gic_config), 389 HANDLE_FUNC(__pkvm_prot_finalize), 390 391 HANDLE_FUNC(__pkvm_host_share_hyp), 392 HANDLE_FUNC(__pkvm_host_unshare_hyp), 393 HANDLE_FUNC(__kvm_adjust_pc), 394 HANDLE_FUNC(__kvm_vcpu_run), 395 HANDLE_FUNC(__kvm_flush_vm_context), 396 HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa), 397 HANDLE_FUNC(__kvm_tlb_flush_vmid_ipa_nsh), 398 HANDLE_FUNC(__kvm_tlb_flush_vmid), 399 HANDLE_FUNC(__kvm_tlb_flush_vmid_range), 400 HANDLE_FUNC(__kvm_flush_cpu_context), 401 HANDLE_FUNC(__kvm_timer_set_cntvoff), 402 HANDLE_FUNC(__vgic_v3_save_vmcr_aprs), 403 HANDLE_FUNC(__vgic_v3_restore_vmcr_aprs), 404 HANDLE_FUNC(__pkvm_vcpu_init_traps), 405 HANDLE_FUNC(__pkvm_init_vm), 406 HANDLE_FUNC(__pkvm_init_vcpu), 407 HANDLE_FUNC(__pkvm_teardown_vm), 408 }; 409 410 static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) 411 { 412 DECLARE_REG(unsigned long, id, host_ctxt, 0); 413 unsigned long hcall_min = 0; 414 hcall_t hfn; 415 416 /* 417 * If pKVM has been initialised then reject any calls to the 418 * early "privileged" hypercalls. Note that we cannot reject 419 * calls to __pkvm_prot_finalize for two reasons: (1) The static 420 * key used to determine initialisation must be toggled prior to 421 * finalisation and (2) finalisation is performed on a per-CPU 422 * basis. This is all fine, however, since __pkvm_prot_finalize 423 * returns -EPERM after the first call for a given CPU. 424 */ 425 if (static_branch_unlikely(&kvm_protected_mode_initialized)) 426 hcall_min = __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize; 427 428 id &= ~ARM_SMCCC_CALL_HINTS; 429 id -= KVM_HOST_SMCCC_ID(0); 430 431 if (unlikely(id < hcall_min || id >= ARRAY_SIZE(host_hcall))) 432 goto inval; 433 434 hfn = host_hcall[id]; 435 if (unlikely(!hfn)) 436 goto inval; 437 438 cpu_reg(host_ctxt, 0) = SMCCC_RET_SUCCESS; 439 hfn(host_ctxt); 440 441 return; 442 inval: 443 cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED; 444 } 445 446 static void default_host_smc_handler(struct kvm_cpu_context *host_ctxt) 447 { 448 __kvm_hyp_host_forward_smc(host_ctxt); 449 } 450 451 static void handle_host_smc(struct kvm_cpu_context *host_ctxt) 452 { 453 DECLARE_REG(u64, func_id, host_ctxt, 0); 454 bool handled; 455 456 func_id &= ~ARM_SMCCC_CALL_HINTS; 457 458 handled = kvm_host_psci_handler(host_ctxt, func_id); 459 if (!handled) 460 handled = kvm_host_ffa_handler(host_ctxt, func_id); 461 if (!handled) 462 default_host_smc_handler(host_ctxt); 463 464 /* SMC was trapped, move ELR past the current PC. */ 465 kvm_skip_host_instr(); 466 } 467 468 void handle_trap(struct kvm_cpu_context *host_ctxt) 469 { 470 u64 esr = read_sysreg_el2(SYS_ESR); 471 472 switch (ESR_ELx_EC(esr)) { 473 case ESR_ELx_EC_HVC64: 474 handle_host_hcall(host_ctxt); 475 break; 476 case ESR_ELx_EC_SMC64: 477 handle_host_smc(host_ctxt); 478 break; 479 case ESR_ELx_EC_SVE: 480 cpacr_clear_set(0, CPACR_ELx_ZEN); 481 isb(); 482 sve_cond_update_zcr_vq(ZCR_ELx_LEN_MASK, SYS_ZCR_EL2); 483 break; 484 case ESR_ELx_EC_IABT_LOW: 485 case ESR_ELx_EC_DABT_LOW: 486 handle_host_mem_abort(host_ctxt); 487 break; 488 default: 489 BUG(); 490 } 491 } 492