xref: /openbmc/linux/arch/sh/include/asm/tlb.h (revision 23c2b932)
1 #ifndef __ASM_SH_TLB_H
2 #define __ASM_SH_TLB_H
3 
4 #ifdef CONFIG_SUPERH64
5 # include <asm/tlb_64.h>
6 #endif
7 
8 #ifndef __ASSEMBLY__
9 #include <linux/pagemap.h>
10 
11 #ifdef CONFIG_MMU
12 #include <linux/swap.h>
13 #include <asm/pgalloc.h>
14 #include <asm/tlbflush.h>
15 #include <asm/mmu_context.h>
16 
17 /*
18  * TLB handling.  This allows us to remove pages from the page
19  * tables, and efficiently handle the TLB issues.
20  */
21 struct mmu_gather {
22 	struct mm_struct	*mm;
23 	unsigned int		fullmm;
24 	unsigned long		start, end;
25 };
26 
27 static inline void init_tlb_gather(struct mmu_gather *tlb)
28 {
29 	tlb->start = TASK_SIZE;
30 	tlb->end = 0;
31 
32 	if (tlb->fullmm) {
33 		tlb->start = 0;
34 		tlb->end = TASK_SIZE;
35 	}
36 }
37 
38 static inline void
39 tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end)
40 {
41 	tlb->mm = mm;
42 	tlb->start = start;
43 	tlb->end = end;
44 	tlb->fullmm = !(start | (end+1));
45 
46 	init_tlb_gather(tlb);
47 }
48 
49 static inline void
50 tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
51 {
52 	if (tlb->fullmm)
53 		flush_tlb_mm(tlb->mm);
54 
55 	/* keep the page table cache within bounds */
56 	check_pgt_cache();
57 }
58 
59 static inline void
60 tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep, unsigned long address)
61 {
62 	if (tlb->start > address)
63 		tlb->start = address;
64 	if (tlb->end < address + PAGE_SIZE)
65 		tlb->end = address + PAGE_SIZE;
66 }
67 
68 /*
69  * In the case of tlb vma handling, we can optimise these away in the
70  * case where we're doing a full MM flush.  When we're doing a munmap,
71  * the vmas are adjusted to only cover the region to be torn down.
72  */
73 static inline void
74 tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
75 {
76 	if (!tlb->fullmm)
77 		flush_cache_range(vma, vma->vm_start, vma->vm_end);
78 }
79 
80 static inline void
81 tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
82 {
83 	if (!tlb->fullmm && tlb->end) {
84 		flush_tlb_range(vma, tlb->start, tlb->end);
85 		init_tlb_gather(tlb);
86 	}
87 }
88 
89 static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
90 {
91 }
92 
93 static inline void tlb_flush_mmu_free(struct mmu_gather *tlb)
94 {
95 }
96 
97 static inline void tlb_flush_mmu(struct mmu_gather *tlb)
98 {
99 }
100 
101 static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
102 {
103 	free_page_and_swap_cache(page);
104 	return 1; /* avoid calling tlb_flush_mmu */
105 }
106 
107 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
108 {
109 	__tlb_remove_page(tlb, page);
110 }
111 
112 #define pte_free_tlb(tlb, ptep, addr)	pte_free((tlb)->mm, ptep)
113 #define pmd_free_tlb(tlb, pmdp, addr)	pmd_free((tlb)->mm, pmdp)
114 #define pud_free_tlb(tlb, pudp, addr)	pud_free((tlb)->mm, pudp)
115 
116 #define tlb_migrate_finish(mm)		do { } while (0)
117 
118 #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SUPERH64)
119 extern void tlb_wire_entry(struct vm_area_struct *, unsigned long, pte_t);
120 extern void tlb_unwire_entry(void);
121 #else
122 static inline void tlb_wire_entry(struct vm_area_struct *vma ,
123 				  unsigned long addr, pte_t pte)
124 {
125 	BUG();
126 }
127 
128 static inline void tlb_unwire_entry(void)
129 {
130 	BUG();
131 }
132 #endif
133 
134 #else /* CONFIG_MMU */
135 
136 #define tlb_start_vma(tlb, vma)				do { } while (0)
137 #define tlb_end_vma(tlb, vma)				do { } while (0)
138 #define __tlb_remove_tlb_entry(tlb, pte, address)	do { } while (0)
139 #define tlb_flush(tlb)					do { } while (0)
140 
141 #include <asm-generic/tlb.h>
142 
143 #endif /* CONFIG_MMU */
144 #endif /* __ASSEMBLY__ */
145 #endif /* __ASM_SH_TLB_H */
146