1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012,2013 - ARM Ltd 4 * Author: Marc Zyngier <marc.zyngier@arm.com> 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 14 #define ARM_EXIT_WITH_SERROR_BIT 31 15 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) 16 #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) 17 #define ARM_SERROR_PENDING(x) !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT)) 18 19 #define ARM_EXCEPTION_IRQ 0 20 #define ARM_EXCEPTION_EL1_SERROR 1 21 #define ARM_EXCEPTION_TRAP 2 22 #define ARM_EXCEPTION_IL 3 23 /* The hyp-stub will return this for any kvm_call_hyp() call */ 24 #define ARM_EXCEPTION_HYP_GONE HVC_STUB_ERR 25 26 #define kvm_arm_exception_type \ 27 {ARM_EXCEPTION_IRQ, "IRQ" }, \ 28 {ARM_EXCEPTION_EL1_SERROR, "SERROR" }, \ 29 {ARM_EXCEPTION_TRAP, "TRAP" }, \ 30 {ARM_EXCEPTION_HYP_GONE, "HYP_GONE" } 31 32 /* 33 * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code 34 * that jumps over this. 35 */ 36 #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) 37 38 #define KVM_HOST_SMCCC_ID(id) \ 39 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 40 ARM_SMCCC_SMC_64, \ 41 ARM_SMCCC_OWNER_VENDOR_HYP, \ 42 (id)) 43 44 #define KVM_HOST_SMCCC_FUNC(name) KVM_HOST_SMCCC_ID(__KVM_HOST_SMCCC_FUNC_##name) 45 46 #define __KVM_HOST_SMCCC_FUNC___kvm_hyp_init 0 47 48 #ifndef __ASSEMBLY__ 49 50 #include <linux/mm.h> 51 52 enum __kvm_host_smccc_func { 53 /* Hypercalls available only prior to pKVM finalisation */ 54 /* __KVM_HOST_SMCCC_FUNC___kvm_hyp_init */ 55 __KVM_HOST_SMCCC_FUNC___kvm_get_mdcr_el2 = __KVM_HOST_SMCCC_FUNC___kvm_hyp_init + 1, 56 __KVM_HOST_SMCCC_FUNC___pkvm_init, 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___kvm_adjust_pc, 68 __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run, 69 __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context, 70 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa, 71 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa_nsh, 72 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid, 73 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_range, 74 __KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context, 75 __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff, 76 __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr, 77 __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr, 78 __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs, 79 __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs, 80 __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_init_traps, 81 __KVM_HOST_SMCCC_FUNC___pkvm_init_vm, 82 __KVM_HOST_SMCCC_FUNC___pkvm_init_vcpu, 83 __KVM_HOST_SMCCC_FUNC___pkvm_teardown_vm, 84 }; 85 86 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 87 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 88 89 /* 90 * Define a pair of symbols sharing the same name but one defined in 91 * VHE and the other in nVHE hyp implementations. 92 */ 93 #define DECLARE_KVM_HYP_SYM(sym) \ 94 DECLARE_KVM_VHE_SYM(sym); \ 95 DECLARE_KVM_NVHE_SYM(sym) 96 97 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 98 DECLARE_PER_CPU(type, sym) 99 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 100 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 101 102 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 103 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 104 DECLARE_KVM_NVHE_PER_CPU(type, sym) 105 106 /* 107 * Compute pointer to a symbol defined in nVHE percpu region. 108 * Returns NULL if percpu memory has not been allocated yet. 109 */ 110 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 111 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 112 ({ \ 113 unsigned long base, off; \ 114 base = kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[cpu]; \ 115 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 116 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 117 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 118 }) 119 120 #if defined(__KVM_NVHE_HYPERVISOR__) 121 122 #define CHOOSE_NVHE_SYM(sym) sym 123 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 124 125 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 126 extern void *__nvhe_undefined_symbol; 127 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 128 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 129 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 130 131 #elif defined(__KVM_VHE_HYPERVISOR__) 132 133 #define CHOOSE_VHE_SYM(sym) sym 134 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 135 136 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 137 extern void *__vhe_undefined_symbol; 138 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 139 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 140 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 141 142 #else 143 144 /* 145 * BIG FAT WARNINGS: 146 * 147 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 148 * to has_vhe(). has_vhe() is implemented as a *final* capability, 149 * while this is used early at boot time, when the capabilities are 150 * not final yet.... 151 * 152 * - Don't let the nVHE hypervisor have access to this, as it will 153 * pick the *wrong* symbol (yes, it runs at EL2...). 154 */ 155 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 156 ? CHOOSE_VHE_SYM(sym) \ 157 : CHOOSE_NVHE_SYM(sym)) 158 159 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 160 ? this_cpu_ptr(&sym) \ 161 : this_cpu_ptr_nvhe_sym(sym)) 162 163 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 164 ? per_cpu_ptr(&sym, cpu) \ 165 : per_cpu_ptr_nvhe_sym(sym, cpu)) 166 167 #define CHOOSE_VHE_SYM(sym) sym 168 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 169 170 #endif 171 172 struct kvm_nvhe_init_params { 173 unsigned long mair_el2; 174 unsigned long tcr_el2; 175 unsigned long tpidr_el2; 176 unsigned long stack_hyp_va; 177 unsigned long stack_pa; 178 phys_addr_t pgd_pa; 179 unsigned long hcr_el2; 180 unsigned long vttbr; 181 unsigned long vtcr; 182 }; 183 184 /* 185 * Used by the host in EL1 to dump the nVHE hypervisor backtrace on 186 * hyp_panic() in non-protected mode. 187 * 188 * @stack_base: hyp VA of the hyp_stack base. 189 * @overflow_stack_base: hyp VA of the hyp_overflow_stack base. 190 * @fp: hyp FP where the backtrace begins. 191 * @pc: hyp PC where the backtrace begins. 192 */ 193 struct kvm_nvhe_stacktrace_info { 194 unsigned long stack_base; 195 unsigned long overflow_stack_base; 196 unsigned long fp; 197 unsigned long pc; 198 }; 199 200 /* Translate a kernel address @ptr into its equivalent linear mapping */ 201 #define kvm_ksym_ref(ptr) \ 202 ({ \ 203 void *val = (ptr); \ 204 if (!is_kernel_in_hyp_mode()) \ 205 val = lm_alias((ptr)); \ 206 val; \ 207 }) 208 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 209 210 struct kvm; 211 struct kvm_vcpu; 212 struct kvm_s2_mmu; 213 214 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 215 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 216 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 217 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 218 219 extern unsigned long kvm_nvhe_sym(kvm_arm_hyp_percpu_base)[]; 220 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 221 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 222 223 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 224 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 225 226 extern void __kvm_flush_vm_context(void); 227 extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu); 228 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 229 int level); 230 extern void __kvm_tlb_flush_vmid_ipa_nsh(struct kvm_s2_mmu *mmu, 231 phys_addr_t ipa, 232 int level); 233 extern void __kvm_tlb_flush_vmid_range(struct kvm_s2_mmu *mmu, 234 phys_addr_t start, unsigned long pages); 235 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 236 237 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 238 239 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 240 241 extern void __kvm_adjust_pc(struct kvm_vcpu *vcpu); 242 243 extern u64 __vgic_v3_get_gic_config(void); 244 extern u64 __vgic_v3_read_vmcr(void); 245 extern void __vgic_v3_write_vmcr(u32 vmcr); 246 extern void __vgic_v3_init_lrs(void); 247 248 extern u64 __kvm_get_mdcr_el2(void); 249 250 #define __KVM_EXTABLE(from, to) \ 251 " .pushsection __kvm_ex_table, \"a\"\n" \ 252 " .align 3\n" \ 253 " .long (" #from " - .), (" #to " - .)\n" \ 254 " .popsection\n" 255 256 257 #define __kvm_at(at_op, addr) \ 258 ( { \ 259 int __kvm_at_err = 0; \ 260 u64 spsr, elr; \ 261 asm volatile( \ 262 " mrs %1, spsr_el2\n" \ 263 " mrs %2, elr_el2\n" \ 264 "1: at "at_op", %3\n" \ 265 " isb\n" \ 266 " b 9f\n" \ 267 "2: msr spsr_el2, %1\n" \ 268 " msr elr_el2, %2\n" \ 269 " mov %w0, %4\n" \ 270 "9:\n" \ 271 __KVM_EXTABLE(1b, 2b) \ 272 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 273 : "r" (addr), "i" (-EFAULT)); \ 274 __kvm_at_err; \ 275 } ) 276 277 void __noreturn hyp_panic(void); 278 asmlinkage void kvm_unexpected_el2_exception(void); 279 asmlinkage void __noreturn hyp_panic(void); 280 asmlinkage void __noreturn hyp_panic_bad_stack(void); 281 asmlinkage void kvm_unexpected_el2_exception(void); 282 struct kvm_cpu_context; 283 void handle_trap(struct kvm_cpu_context *host_ctxt); 284 asmlinkage void __noreturn __kvm_host_psci_cpu_entry(bool is_cpu_on); 285 void __noreturn __pkvm_init_finalise(void); 286 void kvm_nvhe_prepare_backtrace(unsigned long fp, unsigned long pc); 287 void kvm_patch_vector_branch(struct alt_instr *alt, 288 __le32 *origptr, __le32 *updptr, int nr_inst); 289 void kvm_get_kimage_voffset(struct alt_instr *alt, 290 __le32 *origptr, __le32 *updptr, int nr_inst); 291 void kvm_compute_final_ctr_el0(struct alt_instr *alt, 292 __le32 *origptr, __le32 *updptr, int nr_inst); 293 void __noreturn __cold nvhe_hyp_panic_handler(u64 esr, u64 spsr, u64 elr_virt, 294 u64 elr_phys, u64 par, uintptr_t vcpu, u64 far, u64 hpfar); 295 296 #else /* __ASSEMBLY__ */ 297 298 .macro get_host_ctxt reg, tmp 299 adr_this_cpu \reg, kvm_host_data, \tmp 300 add \reg, \reg, #HOST_DATA_CONTEXT 301 .endm 302 303 .macro get_vcpu_ptr vcpu, ctxt 304 get_host_ctxt \ctxt, \vcpu 305 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 306 .endm 307 308 .macro get_loaded_vcpu vcpu, ctxt 309 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 310 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 311 .endm 312 313 .macro set_loaded_vcpu vcpu, ctxt, tmp 314 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 315 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 316 .endm 317 318 /* 319 * KVM extable for unexpected exceptions. 320 * Create a struct kvm_exception_table_entry output to a section that can be 321 * mapped by EL2. The table is not sorted. 322 * 323 * The caller must ensure: 324 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 325 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 326 */ 327 .macro _kvm_extable, from, to 328 .pushsection __kvm_ex_table, "a" 329 .align 3 330 .long (\from - .), (\to - .) 331 .popsection 332 .endm 333 334 #define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) 335 #define CPU_LR_OFFSET CPU_XREG_OFFSET(30) 336 #define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) 337 338 /* 339 * We treat x18 as callee-saved as the host may use it as a platform 340 * register (e.g. for shadow call stack). 341 */ 342 .macro save_callee_saved_regs ctxt 343 str x18, [\ctxt, #CPU_XREG_OFFSET(18)] 344 stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 345 stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 346 stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 347 stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 348 stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 349 stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 350 .endm 351 352 .macro restore_callee_saved_regs ctxt 353 // We require \ctxt is not x18-x28 354 ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] 355 ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 356 ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 357 ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 358 ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 359 ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 360 ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 361 .endm 362 363 .macro save_sp_el0 ctxt, tmp 364 mrs \tmp, sp_el0 365 str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 366 .endm 367 368 .macro restore_sp_el0 ctxt, tmp 369 ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 370 msr sp_el0, \tmp 371 .endm 372 373 #endif 374 375 #endif /* __ARM_KVM_ASM_H__ */ 376