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