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/virt.h> 11 12 #define ARM_EXIT_WITH_SERROR_BIT 31 13 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) 14 #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) 15 #define ARM_SERROR_PENDING(x) !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT)) 16 17 #define ARM_EXCEPTION_IRQ 0 18 #define ARM_EXCEPTION_EL1_SERROR 1 19 #define ARM_EXCEPTION_TRAP 2 20 #define ARM_EXCEPTION_IL 3 21 /* The hyp-stub will return this for any kvm_call_hyp() call */ 22 #define ARM_EXCEPTION_HYP_GONE HVC_STUB_ERR 23 24 #define kvm_arm_exception_type \ 25 {ARM_EXCEPTION_IRQ, "IRQ" }, \ 26 {ARM_EXCEPTION_EL1_SERROR, "SERROR" }, \ 27 {ARM_EXCEPTION_TRAP, "TRAP" }, \ 28 {ARM_EXCEPTION_HYP_GONE, "HYP_GONE" } 29 30 /* 31 * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code 32 * that jumps over this. 33 */ 34 #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) 35 36 #define __SMCCC_WORKAROUND_1_SMC_SZ 36 37 38 #ifndef __ASSEMBLY__ 39 40 #include <linux/mm.h> 41 42 /* 43 * Translate name of a symbol defined in nVHE hyp to the name seen 44 * by kernel proper. All nVHE symbols are prefixed by the build system 45 * to avoid clashes with the VHE variants. 46 */ 47 #define kvm_nvhe_sym(sym) __kvm_nvhe_##sym 48 49 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 50 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 51 52 /* 53 * Define a pair of symbols sharing the same name but one defined in 54 * VHE and the other in nVHE hyp implementations. 55 */ 56 #define DECLARE_KVM_HYP_SYM(sym) \ 57 DECLARE_KVM_VHE_SYM(sym); \ 58 DECLARE_KVM_NVHE_SYM(sym) 59 60 #define CHOOSE_VHE_SYM(sym) sym 61 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 62 63 #ifndef __KVM_NVHE_HYPERVISOR__ 64 /* 65 * BIG FAT WARNINGS: 66 * 67 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 68 * to has_vhe(). has_vhe() is implemented as a *final* capability, 69 * while this is used early at boot time, when the capabilities are 70 * not final yet.... 71 * 72 * - Don't let the nVHE hypervisor have access to this, as it will 73 * pick the *wrong* symbol (yes, it runs at EL2...). 74 */ 75 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() ? CHOOSE_VHE_SYM(sym) \ 76 : CHOOSE_NVHE_SYM(sym)) 77 #else 78 /* The nVHE hypervisor shouldn't even try to access anything */ 79 extern void *__nvhe_undefined_symbol; 80 #define CHOOSE_HYP_SYM(sym) __nvhe_undefined_symbol 81 #endif 82 83 /* Translate a kernel address @ptr into its equivalent linear mapping */ 84 #define kvm_ksym_ref(ptr) \ 85 ({ \ 86 void *val = (ptr); \ 87 if (!is_kernel_in_hyp_mode()) \ 88 val = lm_alias((ptr)); \ 89 val; \ 90 }) 91 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 92 93 struct kvm; 94 struct kvm_vcpu; 95 struct kvm_s2_mmu; 96 97 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 98 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 99 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 100 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 101 102 extern atomic_t arm64_el2_vector_last_slot; 103 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 104 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 105 106 extern void __kvm_flush_vm_context(void); 107 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 108 int level); 109 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 110 extern void __kvm_tlb_flush_local_vmid(struct kvm_s2_mmu *mmu); 111 112 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 113 114 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 115 116 extern void __kvm_enable_ssbs(void); 117 118 extern u64 __vgic_v3_get_ich_vtr_el2(void); 119 extern u64 __vgic_v3_read_vmcr(void); 120 extern void __vgic_v3_write_vmcr(u32 vmcr); 121 extern void __vgic_v3_init_lrs(void); 122 123 extern u32 __kvm_get_mdcr_el2(void); 124 125 extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; 126 127 /* 128 * Obtain the PC-relative address of a kernel symbol 129 * s: symbol 130 * 131 * The goal of this macro is to return a symbol's address based on a 132 * PC-relative computation, as opposed to a loading the VA from a 133 * constant pool or something similar. This works well for HYP, as an 134 * absolute VA is guaranteed to be wrong. Only use this if trying to 135 * obtain the address of a symbol (i.e. not something you obtained by 136 * following a pointer). 137 */ 138 #define hyp_symbol_addr(s) \ 139 ({ \ 140 typeof(s) *addr; \ 141 asm("adrp %0, %1\n" \ 142 "add %0, %0, :lo12:%1\n" \ 143 : "=r" (addr) : "S" (&s)); \ 144 addr; \ 145 }) 146 147 /* 148 * Home-grown __this_cpu_{ptr,read} variants that always work at HYP, 149 * provided that sym is really a *symbol* and not a pointer obtained from 150 * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps 151 * sparse quiet. 152 */ 153 #define __hyp_this_cpu_ptr(sym) \ 154 ({ \ 155 void *__ptr; \ 156 __verify_pcpu_ptr(&sym); \ 157 __ptr = hyp_symbol_addr(sym); \ 158 __ptr += read_sysreg(tpidr_el2); \ 159 (typeof(sym) __kernel __force *)__ptr; \ 160 }) 161 162 #define __hyp_this_cpu_read(sym) \ 163 ({ \ 164 *__hyp_this_cpu_ptr(sym); \ 165 }) 166 167 #define __KVM_EXTABLE(from, to) \ 168 " .pushsection __kvm_ex_table, \"a\"\n" \ 169 " .align 3\n" \ 170 " .long (" #from " - .), (" #to " - .)\n" \ 171 " .popsection\n" 172 173 174 #define __kvm_at(at_op, addr) \ 175 ( { \ 176 int __kvm_at_err = 0; \ 177 u64 spsr, elr; \ 178 asm volatile( \ 179 " mrs %1, spsr_el2\n" \ 180 " mrs %2, elr_el2\n" \ 181 "1: at "at_op", %3\n" \ 182 " isb\n" \ 183 " b 9f\n" \ 184 "2: msr spsr_el2, %1\n" \ 185 " msr elr_el2, %2\n" \ 186 " mov %w0, %4\n" \ 187 "9:\n" \ 188 __KVM_EXTABLE(1b, 2b) \ 189 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 190 : "r" (addr), "i" (-EFAULT)); \ 191 __kvm_at_err; \ 192 } ) 193 194 195 #else /* __ASSEMBLY__ */ 196 197 .macro hyp_adr_this_cpu reg, sym, tmp 198 adr_l \reg, \sym 199 mrs \tmp, tpidr_el2 200 add \reg, \reg, \tmp 201 .endm 202 203 .macro hyp_ldr_this_cpu reg, sym, tmp 204 adr_l \reg, \sym 205 mrs \tmp, tpidr_el2 206 ldr \reg, [\reg, \tmp] 207 .endm 208 209 .macro get_host_ctxt reg, tmp 210 hyp_adr_this_cpu \reg, kvm_host_data, \tmp 211 add \reg, \reg, #HOST_DATA_CONTEXT 212 .endm 213 214 .macro get_vcpu_ptr vcpu, ctxt 215 get_host_ctxt \ctxt, \vcpu 216 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 217 .endm 218 219 /* 220 * KVM extable for unexpected exceptions. 221 * In the same format _asm_extable, but output to a different section so that 222 * it can be mapped to EL2. The KVM version is not sorted. The caller must 223 * ensure: 224 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 225 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 226 */ 227 .macro _kvm_extable, from, to 228 .pushsection __kvm_ex_table, "a" 229 .align 3 230 .long (\from - .), (\to - .) 231 .popsection 232 .endm 233 234 #endif 235 236 #endif /* __ARM_KVM_ASM_H__ */ 237