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 KVM_HOST_SMCCC_ID(id) \ 38 ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ 39 ARM_SMCCC_SMC_64, \ 40 ARM_SMCCC_OWNER_VENDOR_HYP, \ 41 (id)) 42 43 #define KVM_HOST_SMCCC_FUNC(name) KVM_HOST_SMCCC_ID(__KVM_HOST_SMCCC_FUNC_##name) 44 45 #define __KVM_HOST_SMCCC_FUNC___kvm_hyp_init 0 46 #define __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run 1 47 #define __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context 2 48 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa 3 49 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid 4 50 #define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_local_vmid 5 51 #define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff 6 52 #define __KVM_HOST_SMCCC_FUNC___kvm_enable_ssbs 7 53 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_get_ich_vtr_el2 8 54 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr 9 55 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr 10 56 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_init_lrs 11 57 #define __KVM_HOST_SMCCC_FUNC___kvm_get_mdcr_el2 12 58 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs 13 59 #define __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs 14 60 61 #ifndef __ASSEMBLY__ 62 63 #include <linux/mm.h> 64 65 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 66 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 67 68 /* 69 * Define a pair of symbols sharing the same name but one defined in 70 * VHE and the other in nVHE hyp implementations. 71 */ 72 #define DECLARE_KVM_HYP_SYM(sym) \ 73 DECLARE_KVM_VHE_SYM(sym); \ 74 DECLARE_KVM_NVHE_SYM(sym) 75 76 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 77 DECLARE_PER_CPU(type, sym) 78 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 79 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 80 81 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 82 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 83 DECLARE_KVM_NVHE_PER_CPU(type, sym) 84 85 /* 86 * Compute pointer to a symbol defined in nVHE percpu region. 87 * Returns NULL if percpu memory has not been allocated yet. 88 */ 89 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 90 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 91 ({ \ 92 unsigned long base, off; \ 93 base = kvm_arm_hyp_percpu_base[cpu]; \ 94 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 95 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 96 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 97 }) 98 99 #if defined(__KVM_NVHE_HYPERVISOR__) 100 101 #define CHOOSE_NVHE_SYM(sym) sym 102 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 103 104 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 105 extern void *__nvhe_undefined_symbol; 106 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 107 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 108 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 109 110 #elif defined(__KVM_VHE_HYPERVISOR__) 111 112 #define CHOOSE_VHE_SYM(sym) sym 113 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 114 115 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 116 extern void *__vhe_undefined_symbol; 117 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 118 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 119 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 120 121 #else 122 123 /* 124 * BIG FAT WARNINGS: 125 * 126 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 127 * to has_vhe(). has_vhe() is implemented as a *final* capability, 128 * while this is used early at boot time, when the capabilities are 129 * not final yet.... 130 * 131 * - Don't let the nVHE hypervisor have access to this, as it will 132 * pick the *wrong* symbol (yes, it runs at EL2...). 133 */ 134 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 135 ? CHOOSE_VHE_SYM(sym) \ 136 : CHOOSE_NVHE_SYM(sym)) 137 138 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 139 ? this_cpu_ptr(&sym) \ 140 : this_cpu_ptr_nvhe_sym(sym)) 141 142 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 143 ? per_cpu_ptr(&sym, cpu) \ 144 : per_cpu_ptr_nvhe_sym(sym, cpu)) 145 146 #define CHOOSE_VHE_SYM(sym) sym 147 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 148 149 #endif 150 151 struct kvm_nvhe_init_params { 152 unsigned long mair_el2; 153 unsigned long tcr_el2; 154 unsigned long tpidr_el2; 155 unsigned long stack_hyp_va; 156 phys_addr_t pgd_pa; 157 }; 158 159 /* Translate a kernel address @ptr into its equivalent linear mapping */ 160 #define kvm_ksym_ref(ptr) \ 161 ({ \ 162 void *val = (ptr); \ 163 if (!is_kernel_in_hyp_mode()) \ 164 val = lm_alias((ptr)); \ 165 val; \ 166 }) 167 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 168 169 struct kvm; 170 struct kvm_vcpu; 171 struct kvm_s2_mmu; 172 173 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 174 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 175 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 176 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 177 178 extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 179 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 180 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 181 182 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 183 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 184 185 extern void __kvm_flush_vm_context(void); 186 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 187 int level); 188 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 189 extern void __kvm_tlb_flush_local_vmid(struct kvm_s2_mmu *mmu); 190 191 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 192 193 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 194 195 extern u64 __vgic_v3_get_ich_vtr_el2(void); 196 extern u64 __vgic_v3_read_vmcr(void); 197 extern void __vgic_v3_write_vmcr(u32 vmcr); 198 extern void __vgic_v3_init_lrs(void); 199 200 extern u32 __kvm_get_mdcr_el2(void); 201 202 #define __KVM_EXTABLE(from, to) \ 203 " .pushsection __kvm_ex_table, \"a\"\n" \ 204 " .align 3\n" \ 205 " .long (" #from " - .), (" #to " - .)\n" \ 206 " .popsection\n" 207 208 209 #define __kvm_at(at_op, addr) \ 210 ( { \ 211 int __kvm_at_err = 0; \ 212 u64 spsr, elr; \ 213 asm volatile( \ 214 " mrs %1, spsr_el2\n" \ 215 " mrs %2, elr_el2\n" \ 216 "1: at "at_op", %3\n" \ 217 " isb\n" \ 218 " b 9f\n" \ 219 "2: msr spsr_el2, %1\n" \ 220 " msr elr_el2, %2\n" \ 221 " mov %w0, %4\n" \ 222 "9:\n" \ 223 __KVM_EXTABLE(1b, 2b) \ 224 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 225 : "r" (addr), "i" (-EFAULT)); \ 226 __kvm_at_err; \ 227 } ) 228 229 230 #else /* __ASSEMBLY__ */ 231 232 .macro get_host_ctxt reg, tmp 233 adr_this_cpu \reg, kvm_host_data, \tmp 234 add \reg, \reg, #HOST_DATA_CONTEXT 235 .endm 236 237 .macro get_vcpu_ptr vcpu, ctxt 238 get_host_ctxt \ctxt, \vcpu 239 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 240 .endm 241 242 .macro get_loaded_vcpu vcpu, ctxt 243 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 244 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 245 .endm 246 247 .macro set_loaded_vcpu vcpu, ctxt, tmp 248 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 249 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 250 .endm 251 252 /* 253 * KVM extable for unexpected exceptions. 254 * In the same format _asm_extable, but output to a different section so that 255 * it can be mapped to EL2. The KVM version is not sorted. The caller must 256 * ensure: 257 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 258 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 259 */ 260 .macro _kvm_extable, from, to 261 .pushsection __kvm_ex_table, "a" 262 .align 3 263 .long (\from - .), (\to - .) 264 .popsection 265 .endm 266 267 #define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) 268 #define CPU_LR_OFFSET CPU_XREG_OFFSET(30) 269 #define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) 270 271 /* 272 * We treat x18 as callee-saved as the host may use it as a platform 273 * register (e.g. for shadow call stack). 274 */ 275 .macro save_callee_saved_regs ctxt 276 str x18, [\ctxt, #CPU_XREG_OFFSET(18)] 277 stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 278 stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 279 stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 280 stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 281 stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 282 stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 283 .endm 284 285 .macro restore_callee_saved_regs ctxt 286 // We require \ctxt is not x18-x28 287 ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] 288 ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] 289 ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] 290 ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] 291 ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] 292 ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] 293 ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] 294 .endm 295 296 .macro save_sp_el0 ctxt, tmp 297 mrs \tmp, sp_el0 298 str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 299 .endm 300 301 .macro restore_sp_el0 ctxt, tmp 302 ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] 303 msr sp_el0, \tmp 304 .endm 305 306 #endif 307 308 #endif /* __ARM_KVM_ASM_H__ */ 309