1 /* 2 * Copyright (C) 2012 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 #ifndef __ASM_MMU_H 17 #define __ASM_MMU_H 18 19 #define MMCF_AARCH32 0x1 /* mm context flag for AArch32 executables */ 20 #define USER_ASID_BIT 48 21 #define USER_ASID_FLAG (UL(1) << USER_ASID_BIT) 22 #define TTBR_ASID_MASK (UL(0xffff) << 48) 23 24 #ifndef __ASSEMBLY__ 25 26 typedef struct { 27 atomic64_t id; 28 void *vdso; 29 unsigned long flags; 30 } mm_context_t; 31 32 /* 33 * This macro is only used by the TLBI code, which cannot race with an 34 * ASID change and therefore doesn't need to reload the counter using 35 * atomic64_read. 36 */ 37 #define ASID(mm) ((mm)->context.id.counter & 0xffff) 38 39 static inline bool arm64_kernel_unmapped_at_el0(void) 40 { 41 return IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) && 42 cpus_have_const_cap(ARM64_UNMAP_KERNEL_AT_EL0); 43 } 44 45 typedef void (*bp_hardening_cb_t)(void); 46 47 struct bp_hardening_data { 48 int hyp_vectors_slot; 49 bp_hardening_cb_t fn; 50 }; 51 52 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR 53 extern char __bp_harden_hyp_vecs_start[], __bp_harden_hyp_vecs_end[]; 54 55 DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); 56 57 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) 58 { 59 return this_cpu_ptr(&bp_hardening_data); 60 } 61 62 static inline void arm64_apply_bp_hardening(void) 63 { 64 struct bp_hardening_data *d; 65 66 if (!cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR)) 67 return; 68 69 d = arm64_get_bp_hardening_data(); 70 if (d->fn) 71 d->fn(); 72 } 73 #else 74 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) 75 { 76 return NULL; 77 } 78 79 static inline void arm64_apply_bp_hardening(void) { } 80 #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ 81 82 extern void paging_init(void); 83 extern void bootmem_init(void); 84 extern void __iomem *early_io_map(phys_addr_t phys, unsigned long virt); 85 extern void init_mem_pgprot(void); 86 extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, 87 unsigned long virt, phys_addr_t size, 88 pgprot_t prot, bool page_mappings_only); 89 extern void *fixmap_remap_fdt(phys_addr_t dt_phys); 90 extern void mark_linear_text_alias_ro(void); 91 92 #endif /* !__ASSEMBLY__ */ 93 #endif 94