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19#ifndef __ASM_MMU_CONTEXT_H
20#define __ASM_MMU_CONTEXT_H
21
22#define FALKOR_RESERVED_ASID 1
23
24#ifndef __ASSEMBLY__
25
26#include <linux/compiler.h>
27#include <linux/sched.h>
28#include <linux/sched/hotplug.h>
29#include <linux/mm_types.h>
30
31#include <asm/cacheflush.h>
32#include <asm/cpufeature.h>
33#include <asm/proc-fns.h>
34#include <asm-generic/mm_hooks.h>
35#include <asm/cputype.h>
36#include <asm/pgtable.h>
37#include <asm/sysreg.h>
38#include <asm/tlbflush.h>
39
40static inline void contextidr_thread_switch(struct task_struct *next)
41{
42 if (!IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR))
43 return;
44
45 write_sysreg(task_pid_nr(next), contextidr_el1);
46 isb();
47}
48
49
50
51
52static inline void cpu_set_reserved_ttbr0(void)
53{
54 unsigned long ttbr = __pa_symbol(empty_zero_page);
55
56 write_sysreg(ttbr, ttbr0_el1);
57 isb();
58}
59
60
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63
64
65extern u64 idmap_t0sz;
66
67static inline bool __cpu_uses_extended_idmap(void)
68{
69 return (!IS_ENABLED(CONFIG_ARM64_VA_BITS_48) &&
70 unlikely(idmap_t0sz != TCR_T0SZ(VA_BITS)));
71}
72
73
74
75
76static inline void __cpu_set_tcr_t0sz(unsigned long t0sz)
77{
78 unsigned long tcr;
79
80 if (!__cpu_uses_extended_idmap())
81 return;
82
83 tcr = read_sysreg(tcr_el1);
84 tcr &= ~TCR_T0SZ_MASK;
85 tcr |= t0sz << TCR_T0SZ_OFFSET;
86 write_sysreg(tcr, tcr_el1);
87 isb();
88}
89
90#define cpu_set_default_tcr_t0sz() __cpu_set_tcr_t0sz(TCR_T0SZ(VA_BITS))
91#define cpu_set_idmap_tcr_t0sz() __cpu_set_tcr_t0sz(idmap_t0sz)
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104
105static inline void cpu_uninstall_idmap(void)
106{
107 struct mm_struct *mm = current->active_mm;
108
109 cpu_set_reserved_ttbr0();
110 local_flush_tlb_all();
111 cpu_set_default_tcr_t0sz();
112
113 if (mm != &init_mm && !system_uses_ttbr0_pan())
114 cpu_switch_mm(mm->pgd, mm);
115}
116
117static inline void cpu_install_idmap(void)
118{
119 cpu_set_reserved_ttbr0();
120 local_flush_tlb_all();
121 cpu_set_idmap_tcr_t0sz();
122
123 cpu_switch_mm(lm_alias(idmap_pg_dir), &init_mm);
124}
125
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127
128
129
130static inline void cpu_replace_ttbr1(pgd_t *pgd)
131{
132 typedef void (ttbr_replace_func)(phys_addr_t);
133 extern ttbr_replace_func idmap_cpu_replace_ttbr1;
134 ttbr_replace_func *replace_phys;
135
136 phys_addr_t pgd_phys = virt_to_phys(pgd);
137
138 replace_phys = (void *)__pa_symbol(idmap_cpu_replace_ttbr1);
139
140 cpu_install_idmap();
141 replace_phys(pgd_phys);
142 cpu_uninstall_idmap();
143}
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153
154#define destroy_context(mm) do { } while(0)
155void check_and_switch_context(struct mm_struct *mm, unsigned int cpu);
156
157#define init_new_context(tsk,mm) ({ atomic64_set(&(mm)->context.id, 0); 0; })
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167
168static inline void
169enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
170{
171}
172
173#ifdef CONFIG_ARM64_SW_TTBR0_PAN
174static inline void update_saved_ttbr0(struct task_struct *tsk,
175 struct mm_struct *mm)
176{
177 if (system_uses_ttbr0_pan()) {
178 BUG_ON(mm->pgd == swapper_pg_dir);
179 task_thread_info(tsk)->ttbr0 =
180 virt_to_phys(mm->pgd) | ASID(mm) << 48;
181 }
182}
183#else
184static inline void update_saved_ttbr0(struct task_struct *tsk,
185 struct mm_struct *mm)
186{
187}
188#endif
189
190static inline void __switch_mm(struct mm_struct *next)
191{
192 unsigned int cpu = smp_processor_id();
193
194
195
196
197
198 if (next == &init_mm) {
199 cpu_set_reserved_ttbr0();
200 return;
201 }
202
203 check_and_switch_context(next, cpu);
204}
205
206static inline void
207switch_mm(struct mm_struct *prev, struct mm_struct *next,
208 struct task_struct *tsk)
209{
210 if (prev != next)
211 __switch_mm(next);
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220 if (next != &init_mm)
221 update_saved_ttbr0(tsk, next);
222}
223
224#define deactivate_mm(tsk,mm) do { } while (0)
225#define activate_mm(prev,next) switch_mm(prev, next, current)
226
227void verify_cpu_asid_bits(void);
228
229#endif
230
231#endif
232