arch/arm64/include/asm/mmu.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2012 ARM Ltd.
   4  */
   5 #ifndef __ASM_MMU_H
   6 #define __ASM_MMU_H
   7
   8 #include <asm/cputype.h>
   9
  10 #define MMCF_AARCH32    0x1     /* mm context flag for AArch32 executables */
  11 #define USER_ASID_BIT   48
  12 #define USER_ASID_FLAG  (UL(1) << USER_ASID_BIT)
  13 #define TTBR_ASID_MASK  (UL(0xffff) << 48)
  14
  15 #define BP_HARDEN_EL2_SLOTS 4
  16 #define __BP_HARDEN_HYP_VECS_SZ (BP_HARDEN_EL2_SLOTS * SZ_2K)
  17
  18 #ifndef __ASSEMBLY__
  19
  20 typedef struct {
  21         atomic64_t      id;
  22         void            *vdso;
  23         unsigned long   flags;
  24 } mm_context_t;
  25
  26 /*
  27  * This macro is only used by the TLBI and low-level switch_mm() code,
  28  * neither of which can race with an ASID change. We therefore don't
  29  * need to reload the counter using atomic64_read().
  30  */
  31 #define ASID(mm)        ((mm)->context.id.counter & 0xffff)
  32
  33 static inline bool arm64_kernel_unmapped_at_el0(void)
  34 {
  35         return cpus_have_const_cap(ARM64_UNMAP_KERNEL_AT_EL0);
  36 }
  37
  38 typedef void (*bp_hardening_cb_t)(void);
  39
  40 struct bp_hardening_data {
  41         int                     hyp_vectors_slot;
  42         bp_hardening_cb_t       fn;
  43 };
  44
  45 #if (defined(CONFIG_HARDEN_BRANCH_PREDICTOR) || \
  46      defined(CONFIG_HARDEN_EL2_VECTORS))
  47
  48 extern char __bp_harden_hyp_vecs[];
  49 extern atomic_t arm64_el2_vector_last_slot;
  50 #endif  /* CONFIG_HARDEN_BRANCH_PREDICTOR || CONFIG_HARDEN_EL2_VECTORS */
  51
  52 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
  53 DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
  54
  55 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
  56 {
  57         return this_cpu_ptr(&bp_hardening_data);
  58 }
  59
  60 static inline void arm64_apply_bp_hardening(void)
  61 {
  62         struct bp_hardening_data *d;
  63
  64         if (!cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR))
  65                 return;
  66
  67         d = arm64_get_bp_hardening_data();
  68         if (d->fn)
  69                 d->fn();
  70 }
  71 #else
  72 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
  73 {
  74         return NULL;
  75 }
  76
  77 static inline void arm64_apply_bp_hardening(void)       { }
  78 #endif  /* CONFIG_HARDEN_BRANCH_PREDICTOR */
  79
  80 extern void arm64_memblock_init(void);
  81 extern void paging_init(void);
  82 extern void bootmem_init(void);
  83 extern void __iomem *early_io_map(phys_addr_t phys, unsigned long virt);
  84 extern void init_mem_pgprot(void);
  85 extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
  86                                unsigned long virt, phys_addr_t size,
  87                                pgprot_t prot, bool page_mappings_only);
  88 extern void *fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot);
  89 extern void mark_linear_text_alias_ro(void);
  90 extern bool kaslr_requires_kpti(void);
  91
  92 #define INIT_MM_CONTEXT(name)   \
  93         .pgd = init_pg_dir,
  94
  95 #endif  /* !__ASSEMBLY__ */
  96 #endif