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
20 #define USER_ASID_FLAG (UL(1) << 48)
21 #define TTBR_ASID_MASK (UL(0xffff) << 48)
22
23 #ifndef __ASSEMBLY__
24
25 #include <linux/percpu.h>
26
27 typedef struct {
28 atomic64_t id;
29 void *vdso;
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
arm64_kernel_unmapped_at_el0(void)39 static inline bool arm64_kernel_unmapped_at_el0(void)
40 {
41 return IS_ENABLED(CONFIG_UNMAP_KERNEL_AT_EL0) &&
42 cpus_have_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
arm64_get_bp_hardening_data(void)57 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
58 {
59 return this_cpu_ptr(&bp_hardening_data);
60 }
61
arm64_apply_bp_hardening(void)62 static inline void arm64_apply_bp_hardening(void)
63 {
64 struct bp_hardening_data *d;
65
66 if (!cpus_have_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
arm64_get_bp_hardening_data(void)74 static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void)
75 {
76 return NULL;
77 }
78
arm64_apply_bp_hardening(void)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 allow_block_mappings);
89 extern void *fixmap_remap_fdt(phys_addr_t dt_phys);
90
91 #endif /* !__ASSEMBLY__ */
92 #endif
93