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___kvm_adjust_pc, 67 __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run, 68 __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context, 69 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa, 70 __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid, 71 __KVM_HOST_SMCCC_FUNC___kvm_flush_cpu_context, 72 __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff, 73 __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr, 74 __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr, 75 __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs, 76 __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs, 77 __KVM_HOST_SMCCC_FUNC___pkvm_vcpu_init_traps, 78 }; 79 80 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 81 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 82 83 /* 84 * Define a pair of symbols sharing the same name but one defined in 85 * VHE and the other in nVHE hyp implementations. 86 */ 87 #define DECLARE_KVM_HYP_SYM(sym) \ 88 DECLARE_KVM_VHE_SYM(sym); \ 89 DECLARE_KVM_NVHE_SYM(sym) 90 91 #define DECLARE_KVM_VHE_PER_CPU(type, sym) \ 92 DECLARE_PER_CPU(type, sym) 93 #define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ 94 DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) 95 96 #define DECLARE_KVM_HYP_PER_CPU(type, sym) \ 97 DECLARE_KVM_VHE_PER_CPU(type, sym); \ 98 DECLARE_KVM_NVHE_PER_CPU(type, sym) 99 100 /* 101 * Compute pointer to a symbol defined in nVHE percpu region. 102 * Returns NULL if percpu memory has not been allocated yet. 103 */ 104 #define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) 105 #define per_cpu_ptr_nvhe_sym(sym, cpu) \ 106 ({ \ 107 unsigned long base, off; \ 108 base = kvm_arm_hyp_percpu_base[cpu]; \ 109 off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ 110 (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ 111 base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ 112 }) 113 114 #if defined(__KVM_NVHE_HYPERVISOR__) 115 116 #define CHOOSE_NVHE_SYM(sym) sym 117 #define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) 118 119 /* The nVHE hypervisor shouldn't even try to access VHE symbols */ 120 extern void *__nvhe_undefined_symbol; 121 #define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol 122 #define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) 123 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) 124 125 #elif defined(__KVM_VHE_HYPERVISOR__) 126 127 #define CHOOSE_VHE_SYM(sym) sym 128 #define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) 129 130 /* The VHE hypervisor shouldn't even try to access nVHE symbols */ 131 extern void *__vhe_undefined_symbol; 132 #define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol 133 #define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) 134 #define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) 135 136 #else 137 138 /* 139 * BIG FAT WARNINGS: 140 * 141 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 142 * to has_vhe(). has_vhe() is implemented as a *final* capability, 143 * while this is used early at boot time, when the capabilities are 144 * not final yet.... 145 * 146 * - Don't let the nVHE hypervisor have access to this, as it will 147 * pick the *wrong* symbol (yes, it runs at EL2...). 148 */ 149 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ 150 ? CHOOSE_VHE_SYM(sym) \ 151 : CHOOSE_NVHE_SYM(sym)) 152 153 #define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ 154 ? this_cpu_ptr(&sym) \ 155 : this_cpu_ptr_nvhe_sym(sym)) 156 157 #define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ 158 ? per_cpu_ptr(&sym, cpu) \ 159 : per_cpu_ptr_nvhe_sym(sym, cpu)) 160 161 #define CHOOSE_VHE_SYM(sym) sym 162 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 163 164 #endif 165 166 struct kvm_nvhe_init_params { 167 unsigned long mair_el2; 168 unsigned long tcr_el2; 169 unsigned long tpidr_el2; 170 unsigned long stack_hyp_va; 171 phys_addr_t pgd_pa; 172 unsigned long hcr_el2; 173 unsigned long vttbr; 174 unsigned long vtcr; 175 }; 176 177 /* Translate a kernel address @ptr into its equivalent linear mapping */ 178 #define kvm_ksym_ref(ptr) \ 179 ({ \ 180 void *val = (ptr); \ 181 if (!is_kernel_in_hyp_mode()) \ 182 val = lm_alias((ptr)); \ 183 val; \ 184 }) 185 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 186 187 struct kvm; 188 struct kvm_vcpu; 189 struct kvm_s2_mmu; 190 191 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 192 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 193 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 194 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 195 196 extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; 197 DECLARE_KVM_NVHE_SYM(__per_cpu_start); 198 DECLARE_KVM_NVHE_SYM(__per_cpu_end); 199 200 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 201 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 202 203 extern void __kvm_flush_vm_context(void); 204 extern void __kvm_flush_cpu_context(struct kvm_s2_mmu *mmu); 205 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 206 int level); 207 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 208 209 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 210 211 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 212 213 extern void __kvm_adjust_pc(struct kvm_vcpu *vcpu); 214 215 extern u64 __vgic_v3_get_gic_config(void); 216 extern u64 __vgic_v3_read_vmcr(void); 217 extern void __vgic_v3_write_vmcr(u32 vmcr); 218 extern void __vgic_v3_init_lrs(void); 219 220 extern u64 __kvm_get_mdcr_el2(void); 221 222 #define __KVM_EXTABLE(from, to) \ 223 " .pushsection __kvm_ex_table, \"a\"\n" \ 224 " .align 3\n" \ 225 " .long (" #from " - .), (" #to " - .)\n" \ 226 " .popsection\n" 227 228 229 #define __kvm_at(at_op, addr) \ 230 ( { \ 231 int __kvm_at_err = 0; \ 232 u64 spsr, elr; \ 233 asm volatile( \ 234 " mrs %1, spsr_el2\n" \ 235 " mrs %2, elr_el2\n" \ 236 "1: at "at_op", %3\n" \ 237 " isb\n" \ 238 " b 9f\n" \ 239 "2: msr spsr_el2, %1\n" \ 240 " msr elr_el2, %2\n" \ 241 " mov %w0, %4\n" \ 242 "9:\n" \ 243 __KVM_EXTABLE(1b, 2b) \ 244 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 245 : "r" (addr), "i" (-EFAULT)); \ 246 __kvm_at_err; \ 247 } ) 248 249 250 #else /* __ASSEMBLY__ */ 251 252 .macro get_host_ctxt reg, tmp 253 adr_this_cpu \reg, kvm_host_data, \tmp 254 add \reg, \reg, #HOST_DATA_CONTEXT 255 .endm 256 257 .macro get_vcpu_ptr vcpu, ctxt 258 get_host_ctxt \ctxt, \vcpu 259 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 260 .endm 261 262 .macro get_loaded_vcpu vcpu, ctxt 263 adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu 264 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 265 .endm 266 267 .macro set_loaded_vcpu vcpu, ctxt, tmp 268 adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp 269 str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 270 .endm 271 272 /* 273 * KVM extable for unexpected exceptions. 274 * Create a struct kvm_exception_table_entry output to a section that can be 275 * mapped by EL2. The table is not sorted. 276 * 277 * The caller must 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