arch/arm64/include/asm/kvm_asm.h

   1 /*
   2  * Copyright (C) 2012,2013 - ARM Ltd
   3  * Author: Marc Zyngier <marc.zyngier@arm.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #ifndef __ARM_KVM_ASM_H__
  19 #define __ARM_KVM_ASM_H__
  20
  21 #include <asm/virt.h>
  22
  23 #define VCPU_WORKAROUND_2_FLAG_SHIFT    0
  24 #define VCPU_WORKAROUND_2_FLAG          (_AC(1, UL) << VCPU_WORKAROUND_2_FLAG_SHIFT)
  25
  26 #define ARM_EXIT_WITH_SERROR_BIT  31
  27 #define ARM_EXCEPTION_CODE(x)     ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT))
  28 #define ARM_SERROR_PENDING(x)     !!((x) & (1U << ARM_EXIT_WITH_SERROR_BIT))
  29
  30 #define ARM_EXCEPTION_IRQ         0
  31 #define ARM_EXCEPTION_EL1_SERROR  1
  32 #define ARM_EXCEPTION_TRAP        2
  33 /* The hyp-stub will return this for any kvm_call_hyp() call */
  34 #define ARM_EXCEPTION_HYP_GONE    HVC_STUB_ERR
  35
  36 #ifndef __ASSEMBLY__
  37
  38 #include <linux/mm.h>
  39
  40 /* Translate a kernel address of @sym into its equivalent linear mapping */
  41 #define kvm_ksym_ref(sym)                                               \
  42         ({                                                              \
  43                 void *val = &sym;                                       \
  44                 if (!is_kernel_in_hyp_mode())                           \
  45                         val = lm_alias(&sym);                           \
  46                 val;                                                    \
  47          })
  48
  49 struct kvm;
  50 struct kvm_vcpu;
  51
  52 extern char __kvm_hyp_init[];
  53 extern char __kvm_hyp_init_end[];
  54
  55 extern char __kvm_hyp_vector[];
  56
  57 extern void __kvm_flush_vm_context(void);
  58 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
  59 extern void __kvm_tlb_flush_vmid(struct kvm *kvm);
  60 extern void __kvm_tlb_flush_local_vmid(struct kvm_vcpu *vcpu);
  61
  62 extern void __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high);
  63
  64 extern int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu);
  65
  66 extern int __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu);
  67
  68 extern u64 __vgic_v3_get_ich_vtr_el2(void);
  69 extern u64 __vgic_v3_read_vmcr(void);
  70 extern void __vgic_v3_write_vmcr(u32 vmcr);
  71 extern void __vgic_v3_init_lrs(void);
  72
  73 extern u32 __kvm_get_mdcr_el2(void);
  74
  75 extern u32 __init_stage2_translation(void);
  76
  77 /* Home-grown __this_cpu_{ptr,read} variants that always work at HYP */
  78 #define __hyp_this_cpu_ptr(sym)                                         \
  79         ({                                                              \
  80                 void *__ptr = hyp_symbol_addr(sym);                     \
  81                 __ptr += read_sysreg(tpidr_el2);                        \
  82                 (typeof(&sym))__ptr;                                    \
  83          })
  84
  85 #define __hyp_this_cpu_read(sym)                                        \
  86         ({                                                              \
  87                 *__hyp_this_cpu_ptr(sym);                               \
  88          })
  89
  90 #define __KVM_EXTABLE(from, to)                                         \
  91         "       .pushsection    __kvm_ex_table, \"a\"\n"                \
  92         "       .align          3\n"                                    \
  93         "       .long           (" #from " - .), (" #to " - .)\n"       \
  94         "       .popsection\n"
  95
  96
  97 #define __kvm_at(at_op, addr)                                           \
  98 ( {                                                                     \
  99         int __kvm_at_err = 0;                                           \
 100         u64 spsr, elr;                                                  \
 101         asm volatile(                                                   \
 102         "       mrs     %1, spsr_el2\n"                                 \
 103         "       mrs     %2, elr_el2\n"                                  \
 104         "1:     at      "at_op", %3\n"                                  \
 105         "       isb\n"                                                  \
 106         "       b       9f\n"                                           \
 107         "2:     msr     spsr_el2, %1\n"                                 \
 108         "       msr     elr_el2, %2\n"                                  \
 109         "       mov     %w0, %4\n"                                      \
 110         "9:\n"                                                          \
 111         __KVM_EXTABLE(1b, 2b)                                           \
 112         : "+r" (__kvm_at_err), "=&r" (spsr), "=&r" (elr)                \
 113         : "r" (addr), "i" (-EFAULT));                                   \
 114         __kvm_at_err;                                                   \
 115 } )
 116
 117
 118 #else /* __ASSEMBLY__ */
 119
 120 .macro hyp_adr_this_cpu reg, sym, tmp
 121         adr_l   \reg, \sym
 122         mrs     \tmp, tpidr_el2
 123         add     \reg, \reg, \tmp
 124 .endm
 125
 126 .macro hyp_ldr_this_cpu reg, sym, tmp
 127         adr_l   \reg, \sym
 128         mrs     \tmp, tpidr_el2
 129         ldr     \reg,  [\reg, \tmp]
 130 .endm
 131
 132 .macro get_host_ctxt reg, tmp
 133         hyp_adr_this_cpu \reg, kvm_host_cpu_state, \tmp
 134 .endm
 135
 136 .macro get_vcpu_ptr vcpu, ctxt
 137         get_host_ctxt \ctxt, \vcpu
 138         ldr     \vcpu, [\ctxt, #HOST_CONTEXT_VCPU]
 139         kern_hyp_va     \vcpu
 140 .endm
 141
 142 /*
 143  * KVM extable for unexpected exceptions.
 144  * In the same format _asm_extable, but output to a different section so that
 145  * it can be mapped to EL2. The KVM version is not sorted. The caller must
 146  * ensure:
 147  * x18 has the hypervisor value to allow any Shadow-Call-Stack instrumented
 148  * code to write to it, and that SPSR_EL2 and ELR_EL2 are restored by the fixup.
 149  */
 150 .macro  _kvm_extable, from, to
 151         .pushsection    __kvm_ex_table, "a"
 152         .align          3
 153         .long           (\from - .), (\to - .)
 154         .popsection
 155 .endm
 156
 157 #endif
 158
 159 #endif /* __ARM_KVM_ASM_H__ */