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
arm64_kernel_unmapped_at_el0(void)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
arm64_get_bp_hardening_data(void)63 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
64 {
65 return this_cpu_ptr(&bp_hardening_data);
66 }
67
arm64_apply_bp_hardening(void)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
arm64_get_bp_hardening_data(void)80 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
81 {
82 return NULL;
83 }
84
arm64_apply_bp_hardening(void)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
