1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012,2013 - ARM Ltd 4 * Author: Marc Zyngier <[email protected]> 5 */ 6 7 #ifndef __ARM_KVM_ASM_H__ 8 #define __ARM_KVM_ASM_H__ 9 10 #include <asm/hyp_image.h> 11 #include <asm/insn.h> 12 #include <asm/virt.h> 13 #include <asm/sysreg.h> 14 15 #define ARM_EXIT_WITH_SERROR_BIT 31 16 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) 17 #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) 18 #define ARM_SERROR_PENDING(x) !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT)) 19 20 #define ARM_EXCEPTION_IRQ 0 21 #define ARM_EXCEPTION_EL1_SERROR 1 22 #define ARM_EXCEPTION_TRAP 2 23 #define ARM_EXCEPTION_IL 3 24 /* The hyp-stub will return this for any kvm_call_hyp() call */ 25 #define ARM_EXCEPTION_HYP_GONE HVC_STUB_ERR 26 27 #define kvm_arm_exception_type \ 28 {ARM_EXCEPTION_IRQ, "IRQ" }, \ 29 {ARM_EXCEPTION_EL1_SERROR, "SERROR" }, \ 30 {ARM_EXCEPTION_TRAP, "TRAP" }, \ 31 {ARM_EXCEPTION_HYP_GONE, "HYP_GONE" } 32 33 /* 34 * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code 35 * that jumps over this. 36 */ 37 #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) 38 39 #define KVM_HOST_SMCCC_ID(id) \ 40 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 41 ARM_SMCCC_SMC_64, \ 42 ARM_SMCCC_OWNER_VENDOR_HYP, \ 43 (id)) 44 45 #define KVM_HOST_SMCCC_FUNC(name) KVM_HOST_SMCCC_ID(__KVM_HOST_SMCCC_FUNC_##name) 46 47 #define __KVM_HOST_SMCCC_FUNC___kvm_hyp_init 0 48 49 #ifndef __ASSEMBLY__ 50 51 #include <linux/mm.h> 52 53 enum __kvm_host_smccc_func { 54 /* Hypercalls available only prior to pKVM finalisation */ 55 /* __KVM_HOST_SMCCC_FUNC___kvm_hyp_init */ 56 __KVM_HOST_SMCCC_FUNC___pkvm_init = __KVM_HOST_SMCCC_FUNC___kvm_hyp_init + 1, 57 __KVM_HOST_SMCCC_FUNC___pkvm_create_private_mapping, 58 __KVM_HOST_SMCCC_FUNC___pkvm_cpu_set_vector, 59 __KVM_HOST_SMCCC_FUNC___kvm_enable_ssbs, 60 __KVM_HOST_SMCCC_FUNC___vgic_v3_init_lrs, 61 __KVM_HOST_SMCCC_FUNC___vgic_v3_get_gic_config, 62 __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize, 63 64 /* Hypercalls available after pKVM finalisation */ 65 __KVM_HOST_SMCCC_FUNC___pkvm_host_share_hyp, 66 __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_hyp, 67 __KVM_HOST_SMCCC_FUNC___pkvm_host_share_guest, 68 __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_guest, 69 __KVM_HOST_SMCCC_FUNC___pkvm_host_relax_perms_guest, 70 __KVM_HOST_SMCCC_FUNC___pkvm_host_wrprotect_guest, 71 __KVM_HOST_SMCCC_FUNC___pkvm_host_test_clear_young_guest, 72 __KVM_HOST_SMCCC_FUNC___pkvm_host_mkyoung_guest, 73 __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc, 74 __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run, 75 __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context, 76 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa, 77 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa_nsh, 78 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid, 79 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_range, 80 __KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context, 81 __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff, 82 __KVM_HOST_SMCCC_FUNC___vgic_v3_save_vmcr_aprs, 83 __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_vmcr_aprs, 84 __KVM_HOST_SMCCC_FUNC___pkvm_init_vm, 85 __KVM_HOST_SMCCC_FUNC___pkvm_init_vcpu, 86 __KVM_HOST_SMCCC_FUNC___pkvm_teardown_vm, 87 __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_load, 88 __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_put, 89 __KVM_HOST_SMCCC_FUNC___pkvm_tlb_flush_vmid, 90 }; 91 92 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 93 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 94 95 /* 96 * Define a pair of symbols sharing the same name but one defined in 97 * VHE and the other in nVHE hyp implementations. 98 */ 99 #define DECLARE_KVM_HYP_SYM(sym) \ 100 DECLARE_KVM_VHE_SYM(sym); \ 101 DECLARE_KVM_NVHE_SYM(sym) 102 103 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 104 DECLARE_PER_CPU(type, sym) 105 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 106 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 107 108 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 109 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 110 DECLARE_KVM_NVHE_PER_CPU(type, sym) 111 112 /* 113 * Compute pointer to a symbol defined in nVHE percpu region. 114 * Returns NULL if percpu memory has not been allocated yet. 115 */ 116 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 117 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 118 ({ \ 119 unsigned long base, off; \ 120 base = kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; \ 121 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 122 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 123 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 124 }) 125 126 #if defined(__KVM_NVHE_HYPERVISOR__) 127 128 #define CHOOSE_NVHE_SYM(sym) sym 129 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 130 131 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 132 extern void *__nvhe_undefined_symbol; 133 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 134 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 135 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 136 137 #elif defined(__KVM_VHE_HYPERVISOR__) 138 139 #define CHOOSE_VHE_SYM(sym) sym 140 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 141 142 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 143 extern void *__vhe_undefined_symbol; 144 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 145 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 146 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 147 148 #else 149 150 /* 151 * BIG FAT WARNINGS: 152 * 153 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 154 * to has_vhe(). has_vhe() is implemented as a *final* capability, 155 * while this is used early at boot time, when the capabilities are 156 * not final yet.... 157 * 158 * - Don't let the nVHE hypervisor have access to this, as it will 159 * pick the *wrong* symbol (yes, it runs at EL2...). 160 */ 161 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 162 ? CHOOSE_VHE_SYM(sym) \ 163 : CHOOSE_NVHE_SYM(sym)) 164 165 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 166 ? this_cpu_ptr(&sym) \ 167 : this_cpu_ptr_nvhe_sym(sym)) 168 169 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 170 ? per_cpu_ptr(&sym, cpu) \ 171 : per_cpu_ptr_nvhe_sym(sym, cpu)) 172 173 #define CHOOSE_VHE_SYM(sym) sym 174 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 175 176 #endif 177 178 struct kvm_nvhe_init_params { 179 unsigned long mair_el2; 180 unsigned long tcr_el2; 181 unsigned long tpidr_el2; 182 unsigned long stack_hyp_va; 183 unsigned long stack_pa; 184 phys_addr_t pgd_pa; 185 unsigned long hcr_el2; 186 unsigned long vttbr; 187 unsigned long vtcr; 188 unsigned long tmp; 189 }; 190 191 /* 192 * Used by the host in EL1 to dump the nVHE hypervisor backtrace on 193 * hyp_panic() in non-protected mode. 194 * 195 * @stack_base: hyp VA of the hyp_stack base. 196 * @overflow_stack_base: hyp VA of the hyp_overflow_stack base. 197 * @fp: hyp FP where the backtrace begins. 198 * @pc: hyp PC where the backtrace begins. 199 */ 200 struct kvm_nvhe_stacktrace_info { 201 unsigned long stack_base; 202 unsigned long overflow_stack_base; 203 unsigned long fp; 204 unsigned long pc; 205 }; 206 207 /* Translate a kernel address @ptr into its equivalent linear mapping */ 208 #define kvm_ksym_ref(ptr) \ 209 ({ \ 210 void *val = (ptr); \ 211 if (!is_kernel_in_hyp_mode()) \ 212 val = lm_alias((ptr)); \ 213 val; \ 214 }) 215 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 216 217 struct kvm; 218 struct kvm_vcpu; 219 struct kvm_s2_mmu; 220 221 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 222 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 223 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 224 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 225 226 extern unsigned long kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[]; 227 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 228 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 229 230 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 231 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 232 233 extern void __kvm_flush_vm_context(void); 234 extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu); 235 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 236 int level); 237 extern void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, 238 phys_addr_t ipa, 239 int level); 240 extern void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, 241 phys_addr_t start, unsigned long pages); 242 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 243 244 extern int __kvm_tlbi_s1e2(struct kvm_s2_mmu *mmu, u64 va, u64 sys_encoding); 245 246 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 247 extern void __kvm_at_s1e01(struct kvm_vcpu *vcpu, u32 op, u64 vaddr); 248 extern void __kvm_at_s1e2(struct kvm_vcpu *vcpu, u32 op, u64 vaddr); 249 extern void __kvm_at_s12(struct kvm_vcpu *vcpu, u32 op, u64 vaddr); 250 251 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 252 253 extern void __kvm_adjust_pc(struct kvm_vcpu *vcpu); 254 255 extern u64 __vgic_v3_get_gic_config(void); 256 extern void __vgic_v3_init_lrs(void); 257 258 #define __KVM_EXTABLE(from, to) \ 259 " .pushsection __kvm_ex_table, \"a\"\n" \ 260 " .align 3\n" \ 261 " .long (" #from " - .), (" #to " - .)\n" \ 262 " .popsection\n" 263 264 265 #define __kvm_at(at_op, addr) \ 266 ( { \ 267 int __kvm_at_err = 0; \ 268 u64 spsr, elr; \ 269 asm volatile( \ 270 " mrs %1, spsr_el2\n" \ 271 " mrs %2, elr_el2\n" \ 272 "1: " __msr_s(at_op, "%3") "\n" \ 273 " isb\n" \ 274 " b 9f\n" \ 275 "2: msr spsr_el2, %1\n" \ 276 " msr elr_el2, %2\n" \ 277 " mov %w0, %4\n" \ 278 "9:\n" \ 279 __KVM_EXTABLE(1b, 2b) \ 280 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 281 : "r" (addr), "i" (-EFAULT)); \ 282 __kvm_at_err; \ 283 } ) 284 285 void __noreturn hyp_panic(void); 286 asmlinkage void kvm_unexpected_el2_exception(void); 287 asmlinkage void __noreturn hyp_panic(void); 288 asmlinkage void __noreturn hyp_panic_bad_stack(void); 289 asmlinkage void kvm_unexpected_el2_exception(void); 290 struct kvm_cpu_context; 291 void handle_trap(struct kvm_cpu_context *host_ctxt); 292 asmlinkage void __noreturn __kvm_host_psci_cpu_entry(bool is_cpu_on); 293 void __noreturn __pkvm_init_finalise(void); 294 void kvm_nvhe_prepare_backtrace(unsigned long fp, unsigned long pc); 295 void kvm_patch_vector_branch(struct alt_instr *alt, 296 __le32 *origptr, __le32 *updptr, int nr_inst); 297 void kvm_get_kimage_voffset(struct alt_instr *alt, 298 __le32 *origptr, __le32 *updptr, int nr_inst); 299 void kvm_compute_final_ctr_el0(struct alt_instr *alt, 300 __le32 *origptr, __le32 *updptr, int nr_inst); 301 void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, u64 elr_virt, 302 u64 elr_phys, u64 par, uintptr_t vcpu, u64 far, u64 hpfar); 303 304 #else /* __ASSEMBLY__ */ 305 306 .macro get_host_ctxt reg, tmp 307 adr_this_cpu \reg, kvm_host_data, \tmp 308 add \reg, \reg, #HOST_DATA_CONTEXT 309 .endm 310 311 .macro get_vcpu_ptr vcpu, ctxt 312 get_host_ctxt \ctxt, \vcpu 313 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 314 .endm 315 316 .macro get_loaded_vcpu vcpu, ctxt 317 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 318 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 319 .endm 320 321 .macro set_loaded_vcpu vcpu, ctxt, tmp 322 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 323 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 324 .endm 325 326 /* 327 * KVM extable for unexpected exceptions. 328 * Create a struct kvm_exception_table_entry output to a section that can be 329 * mapped by EL2. The table is not sorted. 330 * 331 * The caller must ensure: 332 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 333 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 334 */ 335 .macro _kvm_extable, from, to 336 .pushsection __kvm_ex_table, "a" 337 .align 3 338 .long (\from - .), (\to - .) 339 .popsection 340 .endm 341 342 #define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) 343 #define CPU_LR_OFFSET CPU_XREG_OFFSET(30) 344 #define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) 345 346 /* 347 * We treat x18 as callee-saved as the host may use it as a platform 348 * register (e.g. for shadow call stack). 349 */ 350 .macro save_callee_saved_regs ctxt 351 str x18, [\ctxt, #CPU_XREG_OFFSET(18)] 352 stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 353 stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 354 stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 355 stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 356 stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 357 stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 358 .endm 359 360 .macro restore_callee_saved_regs ctxt 361 // We require \ctxt is not x18-x28 362 ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] 363 ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 364 ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 365 ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 366 ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 367 ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 368 ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 369 .endm 370 371 .macro save_sp_el0 ctxt, tmp 372 mrs \tmp, sp_el0 373 str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 374 .endm 375 376 .macro restore_sp_el0 ctxt, tmp 377 ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 378 msr sp_el0, \tmp 379 .endm 380 381 #endif 382 383 #endif /* __ARM_KVM_ASM_H__ */ 384