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 VCPU_WORKAROUND_2_FLAG_SHIFT 0 13 #define VCPU_WORKAROUND_2_FLAG (_AC(1, UL) << VCPU_WORKAROUND_2_FLAG_SHIFT) 14 15 #define ARM_EXIT_WITH_SERROR_BIT 31 16 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) 17 #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) 18 #define ARM_SERROR_PENDING(x) !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT)) 19 20 #define ARM_EXCEPTION_IRQ 0 21 #define ARM_EXCEPTION_EL1_SERROR 1 22 #define ARM_EXCEPTION_TRAP 2 23 #define ARM_EXCEPTION_IL 3 24 /* The hyp-stub will return this for any kvm_call_hyp() call */ 25 #define ARM_EXCEPTION_HYP_GONE HVC_STUB_ERR 26 27 #define kvm_arm_exception_type \ 28 {ARM_EXCEPTION_IRQ, "IRQ" }, \ 29 {ARM_EXCEPTION_EL1_SERROR, "SERROR" }, \ 30 {ARM_EXCEPTION_TRAP, "TRAP" }, \ 31 {ARM_EXCEPTION_HYP_GONE, "HYP_GONE" } 32 33 /* 34 * Size of the HYP vectors preamble. kvm_patch_vector_branch() generates code 35 * that jumps over this. 36 */ 37 #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE) 38 39 #define __SMCCC_WORKAROUND_1_SMC_SZ 36 40 41 #ifndef __ASSEMBLY__ 42 43 #include <linux/mm.h> 44 45 /* 46 * Translate name of a symbol defined in nVHE hyp to the name seen 47 * by kernel proper. All nVHE symbols are prefixed by the build system 48 * to avoid clashes with the VHE variants. 49 */ 50 #define kvm_nvhe_sym(sym) __kvm_nvhe_##sym 51 52 #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] 53 #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] 54 55 /* 56 * Define a pair of symbols sharing the same name but one defined in 57 * VHE and the other in nVHE hyp implementations. 58 */ 59 #define DECLARE_KVM_HYP_SYM(sym) \ 60 DECLARE_KVM_VHE_SYM(sym); \ 61 DECLARE_KVM_NVHE_SYM(sym) 62 63 #define CHOOSE_VHE_SYM(sym) sym 64 #define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) 65 66 #ifndef __KVM_NVHE_HYPERVISOR__ 67 /* 68 * BIG FAT WARNINGS: 69 * 70 * - Don't be tempted to change the following is_kernel_in_hyp_mode() 71 * to has_vhe(). has_vhe() is implemented as a *final* capability, 72 * while this is used early at boot time, when the capabilities are 73 * not final yet.... 74 * 75 * - Don't let the nVHE hypervisor have access to this, as it will 76 * pick the *wrong* symbol (yes, it runs at EL2...). 77 */ 78 #define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() ? CHOOSE_VHE_SYM(sym) \ 79 : CHOOSE_NVHE_SYM(sym)) 80 #else 81 /* The nVHE hypervisor shouldn't even try to access anything */ 82 extern void *__nvhe_undefined_symbol; 83 #define CHOOSE_HYP_SYM(sym) __nvhe_undefined_symbol 84 #endif 85 86 /* Translate a kernel address @ptr into its equivalent linear mapping */ 87 #define kvm_ksym_ref(ptr) \ 88 ({ \ 89 void *val = (ptr); \ 90 if (!is_kernel_in_hyp_mode()) \ 91 val = lm_alias((ptr)); \ 92 val; \ 93 }) 94 #define kvm_ksym_ref_nvhe(sym) kvm_ksym_ref(kvm_nvhe_sym(sym)) 95 96 struct kvm; 97 struct kvm_vcpu; 98 struct kvm_s2_mmu; 99 100 DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); 101 DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); 102 #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) 103 #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) 104 105 #ifdef CONFIG_KVM_INDIRECT_VECTORS 106 extern atomic_t arm64_el2_vector_last_slot; 107 DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); 108 #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) 109 #endif 110 111 extern void __kvm_flush_vm_context(void); 112 extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, 113 int level); 114 extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu); 115 extern void __kvm_tlb_flush_local_vmid(struct kvm_s2_mmu *mmu); 116 117 extern void __kvm_timer_set_cntvoff(u64 cntvoff); 118 119 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu); 120 121 extern void __kvm_enable_ssbs(void); 122 123 extern u64 __vgic_v3_get_ich_vtr_el2(void); 124 extern u64 __vgic_v3_read_vmcr(void); 125 extern void __vgic_v3_write_vmcr(u32 vmcr); 126 extern void __vgic_v3_init_lrs(void); 127 128 extern u32 __kvm_get_mdcr_el2(void); 129 130 extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; 131 132 /* 133 * Obtain the PC-relative address of a kernel symbol 134 * s: symbol 135 * 136 * The goal of this macro is to return a symbol's address based on a 137 * PC-relative computation, as opposed to a loading the VA from a 138 * constant pool or something similar. This works well for HYP, as an 139 * absolute VA is guaranteed to be wrong. Only use this if trying to 140 * obtain the address of a symbol (i.e. not something you obtained by 141 * following a pointer). 142 */ 143 #define hyp_symbol_addr(s) \ 144 ({ \ 145 typeof(s) *addr; \ 146 asm("adrp %0, %1\n" \ 147 "add %0, %0, :lo12:%1\n" \ 148 : "=r" (addr) : "S" (&s)); \ 149 addr; \ 150 }) 151 152 /* 153 * Home-grown __this_cpu_{ptr,read} variants that always work at HYP, 154 * provided that sym is really a *symbol* and not a pointer obtained from 155 * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps 156 * sparse quiet. 157 */ 158 #define __hyp_this_cpu_ptr(sym) \ 159 ({ \ 160 void *__ptr; \ 161 __verify_pcpu_ptr(&sym); \ 162 __ptr = hyp_symbol_addr(sym); \ 163 __ptr += read_sysreg(tpidr_el2); \ 164 (typeof(sym) __kernel __force *)__ptr; \ 165 }) 166 167 #define __hyp_this_cpu_read(sym) \ 168 ({ \ 169 *__hyp_this_cpu_ptr(sym); \ 170 }) 171 172 #define __KVM_EXTABLE(from, to) \ 173 " .pushsection __kvm_ex_table, \"a\"\n" \ 174 " .align 3\n" \ 175 " .long (" #from " - .), (" #to " - .)\n" \ 176 " .popsection\n" 177 178 179 #define __kvm_at(at_op, addr) \ 180 ( { \ 181 int __kvm_at_err = 0; \ 182 u64 spsr, elr; \ 183 asm volatile( \ 184 " mrs %1, spsr_el2\n" \ 185 " mrs %2, elr_el2\n" \ 186 "1: at "at_op", %3\n" \ 187 " isb\n" \ 188 " b 9f\n" \ 189 "2: msr spsr_el2, %1\n" \ 190 " msr elr_el2, %2\n" \ 191 " mov %w0, %4\n" \ 192 "9:\n" \ 193 __KVM_EXTABLE(1b, 2b) \ 194 : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr) \ 195 : "r" (addr), "i" (-EFAULT)); \ 196 __kvm_at_err; \ 197 } ) 198 199 200 #else /* __ASSEMBLY__ */ 201 202 .macro hyp_adr_this_cpu reg, sym, tmp 203 adr_l \reg, \sym 204 mrs \tmp, tpidr_el2 205 add \reg, \reg, \tmp 206 .endm 207 208 .macro hyp_ldr_this_cpu reg, sym, tmp 209 adr_l \reg, \sym 210 mrs \tmp, tpidr_el2 211 ldr \reg, [\reg, \tmp] 212 .endm 213 214 .macro get_host_ctxt reg, tmp 215 hyp_adr_this_cpu \reg, kvm_host_data, \tmp 216 add \reg, \reg, #HOST_DATA_CONTEXT 217 .endm 218 219 .macro get_vcpu_ptr vcpu, ctxt 220 get_host_ctxt \ctxt, \vcpu 221 ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] 222 .endm 223 224 /* 225 * KVM extable for unexpected exceptions. 226 * In the same format _asm_extable, but output to a different section so that 227 * it can be mapped to EL2. The KVM version is not sorted. The caller must 228 * ensure: 229 * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented 230 * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup. 231 */ 232 .macro _kvm_extable, from, to 233 .pushsection __kvm_ex_table, "a" 234 .align 3 235 .long (\from - .), (\to - .) 236 .popsection 237 .endm 238 239 #endif 240 241 #endif /* __ARM_KVM_ASM_H__ */ 242