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/virt.h> 12 13 #define ARM_EXIT_WITH_SERROR_BIT 31 14 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) 15 #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) 16 #define ARM_SERROR_PENDING(x) !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT)) 17 18 #define ARM_EXCEPTION_IRQ 0 19 #define ARM_EXCEPTION_EL1_SERROR 1 20 #define ARM_EXCEPTION_TRAP 2 21 #define ARM_EXCEPTION_IL 3 22 /* The hyp-stub will return this for any kvm_call_hyp() call */ 23 #define ARM_EXCEPTION_HYP_GONE HVC_STUB_ERR 24 25 #define kvm_arm_exception_type \ 26 {ARM_EXCEPTION_IRQ, "IRQ" }, \ 27 {ARM_EXCEPTION_EL1_SERROR, "SERROR" }, \ 28 {ARM_EXCEPTION_TRAP, "TRAP" }, \ 29 {ARM_EXCEPTION_HYP_GONE, "HYP_GONE" } 30 31 /* 32 * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code 33 * that jumps over this. 34 */ 35 #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) 36 37 #define __SMCCC_WORKAROUND_1_SMC_SZ 36 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 #define __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run 1 49 #define __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context 2 50 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa 3 51 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid 4 52 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_local_vmid 5 53 #define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff 6 54 #define __KVM_HOST_SMCCC_FUNC___kvm_enable_ssbs 7 55 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_get_ich_vtr_el2 8 56 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr 9 57 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr 10 58 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_init_lrs 11 59 #define __KVM_HOST_SMCCC_FUNC___kvm_get_mdcr_el2 12 60 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs 13 61 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs 14 62 63 #ifndef __ASSEMBLY__ 64 65 #include <linux/mm.h> 66 67 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 68 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 69 70 /* 71 * Define a pair of symbols sharing the same name but one defined in 72 * VHE and the other in nVHE hyp implementations. 73 */ 74 #define DECLARE_KVM_HYP_SYM(sym) \ 75 DECLARE_KVM_VHE_SYM(sym); \ 76 DECLARE_KVM_NVHE_SYM(sym) 77 78 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 79 DECLARE_PER_CPU(type, sym) 80 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 81 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 82 83 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 84 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 85 DECLARE_KVM_NVHE_PER_CPU(type, sym) 86 87 /* 88 * Compute pointer to a symbol defined in nVHE percpu region. 89 * Returns NULL if percpu memory has not been allocated yet. 90 */ 91 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 92 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 93 ({ \ 94 unsigned long base, off; \ 95 base = kvm_arm_hyp_percpu_base[cpu]; \ 96 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 97 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 98 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 99 }) 100 101 #if defined(__KVM_NVHE_HYPERVISOR__) 102 103 #define CHOOSE_NVHE_SYM(sym) sym 104 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 105 106 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 107 extern void *__nvhe_undefined_symbol; 108 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 109 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 110 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 111 112 #elif defined(__KVM_VHE_HYPERVISOR__) 113 114 #define CHOOSE_VHE_SYM(sym) sym 115 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 116 117 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 118 extern void *__vhe_undefined_symbol; 119 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 120 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 121 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 122 123 #else 124 125 /* 126 * BIG FAT WARNINGS: 127 * 128 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 129 * to has_vhe(). has_vhe() is implemented as a *final* capability, 130 * while this is used early at boot time, when the capabilities are 131 * not final yet.... 132 * 133 * - Don't let the nVHE hypervisor have access to this, as it will 134 * pick the *wrong* symbol (yes, it runs at EL2...). 135 */ 136 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 137 ? CHOOSE_VHE_SYM(sym) \ 138 : CHOOSE_NVHE_SYM(sym)) 139 140 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 141 ? this_cpu_ptr(&sym) \ 142 : this_cpu_ptr_nvhe_sym(sym)) 143 144 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 145 ? per_cpu_ptr(&sym, cpu) \ 146 : per_cpu_ptr_nvhe_sym(sym, cpu)) 147 148 #define CHOOSE_VHE_SYM(sym) sym 149 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 150 151 #endif 152 153 /* Translate a kernel address @ptr into its equivalent linear mapping */ 154 #define kvm_ksym_ref(ptr) \ 155 ({ \ 156 void *val = (ptr); \ 157 if (!is_kernel_in_hyp_mode()) \ 158 val = lm_alias((ptr)); \ 159 val; \ 160 }) 161 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 162 163 struct kvm; 164 struct kvm_vcpu; 165 struct kvm_s2_mmu; 166 167 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 168 DECLARE_KVM_NVHE_SYM(__kvm_hyp_host_vector); 169 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 170 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 171 #define __kvm_hyp_host_vector CHOOSE_NVHE_SYM(__kvm_hyp_host_vector) 172 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 173 174 extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 175 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 176 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 177 178 extern atomic_t arm64_el2_vector_last_slot; 179 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 180 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 181 182 extern void __kvm_flush_vm_context(void); 183 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 184 int level); 185 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 186 extern void __kvm_tlb_flush_local_vmid(struct kvm_s2_mmu *mmu); 187 188 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 189 190 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 191 192 extern void __kvm_enable_ssbs(void); 193 194 extern u64 __vgic_v3_get_ich_vtr_el2(void); 195 extern u64 __vgic_v3_read_vmcr(void); 196 extern void __vgic_v3_write_vmcr(u32 vmcr); 197 extern void __vgic_v3_init_lrs(void); 198 199 extern u32 __kvm_get_mdcr_el2(void); 200 201 extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; 202 203 /* 204 * Obtain the PC-relative address of a kernel symbol 205 * s: symbol 206 * 207 * The goal of this macro is to return a symbol's address based on a 208 * PC-relative computation, as opposed to a loading the VA from a 209 * constant pool or something similar. This works well for HYP, as an 210 * absolute VA is guaranteed to be wrong. Only use this if trying to 211 * obtain the address of a symbol (i.e. not something you obtained by 212 * following a pointer). 213 */ 214 #define hyp_symbol_addr(s) \ 215 ({ \ 216 typeof(s) *addr; \ 217 asm("adrp %0, %1\n" \ 218 "add %0, %0, :lo12:%1\n" \ 219 : "=r" (addr) : "S" (&s)); \ 220 addr; \ 221 }) 222 223 #define __KVM_EXTABLE(from, to) \ 224 " .pushsection __kvm_ex_table, \"a\"\n" \ 225 " .align 3\n" \ 226 " .long (" #from " - .), (" #to " - .)\n" \ 227 " .popsection\n" 228 229 230 #define __kvm_at(at_op, addr) \ 231 ( { \ 232 int __kvm_at_err = 0; \ 233 u64 spsr, elr; \ 234 asm volatile( \ 235 " mrs %1, spsr_el2\n" \ 236 " mrs %2, elr_el2\n" \ 237 "1: at "at_op", %3\n" \ 238 " isb\n" \ 239 " b 9f\n" \ 240 "2: msr spsr_el2, %1\n" \ 241 " msr elr_el2, %2\n" \ 242 " mov %w0, %4\n" \ 243 "9:\n" \ 244 __KVM_EXTABLE(1b, 2b) \ 245 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 246 : "r" (addr), "i" (-EFAULT)); \ 247 __kvm_at_err; \ 248 } ) 249 250 251 #else /* __ASSEMBLY__ */ 252 253 .macro get_host_ctxt reg, tmp 254 adr_this_cpu \reg, kvm_host_data, \tmp 255 add \reg, \reg, #HOST_DATA_CONTEXT 256 .endm 257 258 .macro get_vcpu_ptr vcpu, ctxt 259 get_host_ctxt \ctxt, \vcpu 260 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 261 .endm 262 263 .macro get_loaded_vcpu vcpu, ctxt 264 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 265 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 266 .endm 267 268 .macro set_loaded_vcpu vcpu, ctxt, tmp 269 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 270 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 271 .endm 272 273 /* 274 * KVM extable for unexpected exceptions. 275 * In the same format _asm_extable, but output to a different section so that 276 * it can be mapped to EL2. The KVM version is not sorted. The caller must 277 * ensure: 278 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 279 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 280 */ 281 .macro _kvm_extable, from, to 282 .pushsection __kvm_ex_table, "a" 283 .align 3 284 .long (\from - .), (\to - .) 285 .popsection 286 .endm 287 288 #define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) 289 #define CPU_LR_OFFSET CPU_XREG_OFFSET(30) 290 #define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) 291 292 /* 293 * We treat x18 as callee-saved as the host may use it as a platform 294 * register (e.g. for shadow call stack). 295 */ 296 .macro save_callee_saved_regs ctxt 297 str x18, [\ctxt, #CPU_XREG_OFFSET(18)] 298 stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 299 stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 300 stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 301 stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 302 stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 303 stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 304 .endm 305 306 .macro restore_callee_saved_regs ctxt 307 // We require \ctxt is not x18-x28 308 ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] 309 ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 310 ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 311 ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 312 ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 313 ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 314 ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 315 .endm 316 317 .macro save_sp_el0 ctxt, tmp 318 mrs \tmp, sp_el0 319 str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 320 .endm 321 322 .macro restore_sp_el0 ctxt, tmp 323 ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 324 msr sp_el0, \tmp 325 .endm 326 327 #endif 328 329 #endif /* __ARM_KVM_ASM_H__ */ 330
