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 #define BP_HARDEN_EL2_SLOTS 4 25 26 #ifndef __ASSEMBLY__ 27 28 typedef struct { 29 atomic64_t id; 30 void *vdso; 31 unsigned long flags; 32 } mm_context_t; 33 34 /* 35 * This macro is only used by the TLBI code, which cannot race with an 36 * ASID change and therefore doesn't need to reload the counter using 37 * atomic64_read. 38 */ 39 #define ASID(mm) ((mm)->context.id.counter & 0xffff) 40 41 static inline bool arm64_kernel_unmapped_at_el0(void) 42 { 43 return IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) && 44 cpus_have_const_cap(ARM64_UNMAP_KERNEL_AT_EL0); 45 } 46 47 typedef void (*bp_hardening_cb_t)(void); 48 49 struct bp_hardening_data { 50 int hyp_vectors_slot; 51 bp_hardening_cb_t fn; 52 }; 53 54 #if (defined(CONFIG_HARDEN_BRANCH_PREDICTOR) || \ 55 defined(CONFIG_HARDEN_EL2_VECTORS)) 56 extern char __bp_harden_hyp_vecs_start[], __bp_harden_hyp_vecs_end[]; 57 extern atomic_t arm64_el2_vector_last_slot; 58 #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR || CONFIG_HARDEN_EL2_VECTORS */ 59 60 #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR 61 DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); 62 63 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) 64 { 65 return this_cpu_ptr(&bp_hardening_data); 66 } 67 68 static inline void arm64_apply_bp_hardening(void) 69 { 70 struct bp_hardening_data *d; 71 72 if (!cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR)) 73 return; 74 75 d = arm64_get_bp_hardening_data(); 76 if (d->fn) 77 d->fn(); 78 } 79 #else 80 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) 81 { 82 return NULL; 83 } 84 85 static inline void arm64_apply_bp_hardening(void) { } 86 #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ 87 88 extern void paging_init(void); 89 extern void bootmem_init(void); 90 extern void __iomem *early_io_map(phys_addr_t phys, unsigned long virt); 91 extern void init_mem_pgprot(void); 92 extern void create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys, 93 unsigned long virt, phys_addr_t size, 94 pgprot_t prot, bool page_mappings_only); 95 extern void *fixmap_remap_fdt(phys_addr_t dt_phys); 96 extern void mark_linear_text_alias_ro(void); 97 98 #endif /* !__ASSEMBLY__ */ 99 #endif 100