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, 72 __KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context, 73 __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff, 74 __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr, 75 __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr, 76 __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs, 77 __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs, 78 __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_init_traps, 79 }; 80 81 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 82 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 83 84 /* 85 * Define a pair of symbols sharing the same name but one defined in 86 * VHE and the other in nVHE hyp implementations. 87 */ 88 #define DECLARE_KVM_HYP_SYM(sym) \ 89 DECLARE_KVM_VHE_SYM(sym); \ 90 DECLARE_KVM_NVHE_SYM(sym) 91 92 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 93 DECLARE_PER_CPU(type, sym) 94 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 95 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 96 97 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 98 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 99 DECLARE_KVM_NVHE_PER_CPU(type, sym) 100 101 /* 102 * Compute pointer to a symbol defined in nVHE percpu region. 103 * Returns NULL if percpu memory has not been allocated yet. 104 */ 105 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 106 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 107 ({ \ 108 unsigned long base, off; \ 109 base = kvm_arm_hyp_percpu_base[cpu]; \ 110 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 111 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 112 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 113 }) 114 115 #if defined(__KVM_NVHE_HYPERVISOR__) 116 117 #define CHOOSE_NVHE_SYM(sym) sym 118 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 119 120 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 121 extern void *__nvhe_undefined_symbol; 122 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 123 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 124 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 125 126 #elif defined(__KVM_VHE_HYPERVISOR__) 127 128 #define CHOOSE_VHE_SYM(sym) sym 129 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 130 131 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 132 extern void *__vhe_undefined_symbol; 133 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 134 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 135 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 136 137 #else 138 139 /* 140 * BIG FAT WARNINGS: 141 * 142 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 143 * to has_vhe(). has_vhe() is implemented as a *final* capability, 144 * while this is used early at boot time, when the capabilities are 145 * not final yet.... 146 * 147 * - Don't let the nVHE hypervisor have access to this, as it will 148 * pick the *wrong* symbol (yes, it runs at EL2...). 149 */ 150 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 151 ? CHOOSE_VHE_SYM(sym) \ 152 : CHOOSE_NVHE_SYM(sym)) 153 154 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 155 ? this_cpu_ptr(&sym) \ 156 : this_cpu_ptr_nvhe_sym(sym)) 157 158 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 159 ? per_cpu_ptr(&sym, cpu) \ 160 : per_cpu_ptr_nvhe_sym(sym, cpu)) 161 162 #define CHOOSE_VHE_SYM(sym) sym 163 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 164 165 #endif 166 167 struct kvm_nvhe_init_params { 168 unsigned long mair_el2; 169 unsigned long tcr_el2; 170 unsigned long tpidr_el2; 171 unsigned long stack_hyp_va; 172 unsigned long stack_pa; 173 phys_addr_t pgd_pa; 174 unsigned long hcr_el2; 175 unsigned long vttbr; 176 unsigned long vtcr; 177 }; 178 179 /* 180 * Used by the host in EL1 to dump the nVHE hypervisor backtrace on 181 * hyp_panic() in non-protected mode. 182 * 183 * @stack_base: hyp VA of the hyp_stack base. 184 * @overflow_stack_base: hyp VA of the hyp_overflow_stack base. 185 * @fp: hyp FP where the backtrace begins. 186 * @pc: hyp PC where the backtrace begins. 187 */ 188 struct kvm_nvhe_stacktrace_info { 189 unsigned long stack_base; 190 unsigned long overflow_stack_base; 191 unsigned long fp; 192 unsigned long pc; 193 }; 194 195 /* Translate a kernel address @ptr into its equivalent linear mapping */ 196 #define kvm_ksym_ref(ptr) \ 197 ({ \ 198 void *val = (ptr); \ 199 if (!is_kernel_in_hyp_mode()) \ 200 val = lm_alias((ptr)); \ 201 val; \ 202 }) 203 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 204 205 struct kvm; 206 struct kvm_vcpu; 207 struct kvm_s2_mmu; 208 209 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 210 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 211 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 212 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 213 214 extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 215 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 216 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 217 218 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 219 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 220 221 extern void __kvm_flush_vm_context(void); 222 extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu); 223 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 224 int level); 225 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 226 227 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 228 229 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 230 231 extern void __kvm_adjust_pc(struct kvm_vcpu *vcpu); 232 233 extern u64 __vgic_v3_get_gic_config(void); 234 extern u64 __vgic_v3_read_vmcr(void); 235 extern void __vgic_v3_write_vmcr(u32 vmcr); 236 extern void __vgic_v3_init_lrs(void); 237 238 extern u64 __kvm_get_mdcr_el2(void); 239 240 #define __KVM_EXTABLE(from, to) \ 241 " .pushsection __kvm_ex_table, \"a\"\n" \ 242 " .align 3\n" \ 243 " .long (" #from " - .), (" #to " - .)\n" \ 244 " .popsection\n" 245 246 247 #define __kvm_at(at_op, addr) \ 248 ( { \ 249 int __kvm_at_err = 0; \ 250 u64 spsr, elr; \ 251 asm volatile( \ 252 " mrs %1, spsr_el2\n" \ 253 " mrs %2, elr_el2\n" \ 254 "1: at "at_op", %3\n" \ 255 " isb\n" \ 256 " b 9f\n" \ 257 "2: msr spsr_el2, %1\n" \ 258 " msr elr_el2, %2\n" \ 259 " mov %w0, %4\n" \ 260 "9:\n" \ 261 __KVM_EXTABLE(1b, 2b) \ 262 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 263 : "r" (addr), "i" (-EFAULT)); \ 264 __kvm_at_err; \ 265 } ) 266 267 268 #else /* __ASSEMBLY__ */ 269 270 .macro get_host_ctxt reg, tmp 271 adr_this_cpu \reg, kvm_host_data, \tmp 272 add \reg, \reg, #HOST_DATA_CONTEXT 273 .endm 274 275 .macro get_vcpu_ptr vcpu, ctxt 276 get_host_ctxt \ctxt, \vcpu 277 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 278 .endm 279 280 .macro get_loaded_vcpu vcpu, ctxt 281 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 282 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 283 .endm 284 285 .macro set_loaded_vcpu vcpu, ctxt, tmp 286 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 287 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 288 .endm 289 290 /* 291 * KVM extable for unexpected exceptions. 292 * Create a struct kvm_exception_table_entry output to a section that can be 293 * mapped by EL2. The table is not sorted. 294 * 295 * The caller must ensure: 296 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 297 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 298 */ 299 .macro _kvm_extable, from, to 300 .pushsection __kvm_ex_table, "a" 301 .align 3 302 .long (\from - .), (\to - .) 303 .popsection 304 .endm 305 306 #define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) 307 #define CPU_LR_OFFSET CPU_XREG_OFFSET(30) 308 #define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) 309 310 /* 311 * We treat x18 as callee-saved as the host may use it as a platform 312 * register (e.g. for shadow call stack). 313 */ 314 .macro save_callee_saved_regs ctxt 315 str x18, [\ctxt, #CPU_XREG_OFFSET(18)] 316 stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 317 stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 318 stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 319 stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 320 stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 321 stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 322 .endm 323 324 .macro restore_callee_saved_regs ctxt 325 // We require \ctxt is not x18-x28 326 ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] 327 ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 328 ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 329 ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 330 ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 331 ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 332 ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 333 .endm 334 335 .macro save_sp_el0 ctxt, tmp 336 mrs \tmp, sp_el0 337 str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 338 .endm 339 340 .macro restore_sp_el0 ctxt, tmp 341 ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 342 msr sp_el0, \tmp 343 .endm 344 345 #endif 346 347 #endif /* __ARM_KVM_ASM_H__ */ 348