xref: /openbmc/linux/arch/sh/include/asm/tlb.h (revision cfbb9be8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_TLB_H
3 #define __ASM_SH_TLB_H
4 
5 #ifdef CONFIG_SUPERH64
6 # include <asm/tlb_64.h>
7 #endif
8 
9 #ifndef __ASSEMBLY__
10 #include <linux/pagemap.h>
11 
12 #ifdef CONFIG_MMU
13 #include <linux/swap.h>
14 #include <asm/pgalloc.h>
15 #include <asm/tlbflush.h>
16 #include <asm/mmu_context.h>
17 
18 /*
19  * TLB handling.  This allows us to remove pages from the page
20  * tables, and efficiently handle the TLB issues.
21  */
22 struct mmu_gather {
23 	struct mm_struct	*mm;
24 	unsigned int		fullmm;
25 	unsigned long		start, end;
26 };
27 
28 static inline void init_tlb_gather(struct mmu_gather *tlb)
29 {
30 	tlb->start = TASK_SIZE;
31 	tlb->end = 0;
32 
33 	if (tlb->fullmm) {
34 		tlb->start = 0;
35 		tlb->end = TASK_SIZE;
36 	}
37 }
38 
39 static inline void
40 arch_tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
41 		unsigned long start, unsigned long end)
42 {
43 	tlb->mm = mm;
44 	tlb->start = start;
45 	tlb->end = end;
46 	tlb->fullmm = !(start | (end+1));
47 
48 	init_tlb_gather(tlb);
49 }
50 
51 static inline void
52 arch_tlb_finish_mmu(struct mmu_gather *tlb,
53 		unsigned long start, unsigned long end, bool force)
54 {
55 	if (tlb->fullmm || force)
56 		flush_tlb_mm(tlb->mm);
57 
58 	/* keep the page table cache within bounds */
59 	check_pgt_cache();
60 }
61 
62 static inline void
63 tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long address)
64 {
65 	if (tlb->start > address)
66 		tlb->start = address;
67 	if (tlb->end < address + PAGE_SIZE)
68 		tlb->end = address + PAGE_SIZE;
69 }
70 
71 #define tlb_remove_huge_tlb_entry(h, tlb, ptep, address)	\
72 	tlb_remove_tlb_entry(tlb, ptep, address)
73 
74 /*
75  * In the case of tlb vma handling, we can optimise these away in the
76  * case where we're doing a full MM flush.  When we're doing a munmap,
77  * the vmas are adjusted to only cover the region to be torn down.
78  */
79 static inline void
80 tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
81 {
82 	if (!tlb->fullmm)
83 		flush_cache_range(vma, vma->vm_start, vma->vm_end);
84 }
85 
86 static inline void
87 tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
88 {
89 	if (!tlb->fullmm && tlb->end) {
90 		flush_tlb_range(vma, tlb->start, tlb->end);
91 		init_tlb_gather(tlb);
92 	}
93 }
94 
95 static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
96 {
97 }
98 
99 static inline void tlb_flush_mmu_free(struct mmu_gather *tlb)
100 {
101 }
102 
103 static inline void tlb_flush_mmu(struct mmu_gather *tlb)
104 {
105 }
106 
107 static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
108 {
109 	free_page_and_swap_cache(page);
110 	return false; /* avoid calling tlb_flush_mmu */
111 }
112 
113 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
114 {
115 	__tlb_remove_page(tlb, page);
116 }
117 
118 static inline bool __tlb_remove_page_size(struct mmu_gather *tlb,
119 					  struct page *page, int page_size)
120 {
121 	return __tlb_remove_page(tlb, page);
122 }
123 
124 static inline void tlb_remove_page_size(struct mmu_gather *tlb,
125 					struct page *page, int page_size)
126 {
127 	return tlb_remove_page(tlb, page);
128 }
129 
130 #define tlb_remove_check_page_size_change tlb_remove_check_page_size_change
131 static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb,
132 						     unsigned int page_size)
133 {
134 }
135 
136 #define pte_free_tlb(tlb, ptep, addr)	pte_free((tlb)->mm, ptep)
137 #define pmd_free_tlb(tlb, pmdp, addr)	pmd_free((tlb)->mm, pmdp)
138 #define pud_free_tlb(tlb, pudp, addr)	pud_free((tlb)->mm, pudp)
139 
140 #define tlb_migrate_finish(mm)		do { } while (0)
141 
142 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SUPERH64)
143 extern void tlb_wire_entry(struct vm_area_struct *, unsigned long, pte_t);
144 extern void tlb_unwire_entry(void);
145 #else
146 static inline void tlb_wire_entry(struct vm_area_struct *vma ,
147 				  unsigned long addr, pte_t pte)
148 {
149 	BUG();
150 }
151 
152 static inline void tlb_unwire_entry(void)
153 {
154 	BUG();
155 }
156 #endif
157 
158 #else /* CONFIG_MMU */
159 
160 #define tlb_start_vma(tlb, vma)				do { } while (0)
161 #define tlb_end_vma(tlb, vma)				do { } while (0)
162 #define __tlb_remove_tlb_entry(tlb, pte, address)	do { } while (0)
163 #define tlb_flush(tlb)					do { } while (0)
164 
165 #include <asm-generic/tlb.h>
166 
167 #endif /* CONFIG_MMU */
168 #endif /* __ASSEMBLY__ */
169 #endif /* __ASM_SH_TLB_H */
170