1 #ifndef __UM_TLB_H
2 #define __UM_TLB_H
3
4 #include <linux/pagemap.h>
5 #include <linux/swap.h>
6 #include <asm/percpu.h>
7 #include <asm/pgalloc.h>
8 #include <asm/tlbflush.h>
9
10 #define tlb_start_vma(tlb, vma) do { } while (0)
11 #define tlb_end_vma(tlb, vma) do { } while (0)
12 #define tlb_flush(tlb) flush_tlb_mm((tlb)->mm)
13
14 /* struct mmu_gather is an opaque type used by the mm code for passing around
15 * any data needed by arch specific code for tlb_remove_page.
16 */
17 struct mmu_gather {
18 struct mm_struct *mm;
19 unsigned int need_flush; /* Really unmapped some ptes? */
20 unsigned long start;
21 unsigned long end;
22 unsigned int fullmm; /* non-zero means full mm flush */
23 };
24
__tlb_remove_tlb_entry(struct mmu_gather * tlb,pte_t * ptep,unsigned long address)25 static inline void __tlb_remove_tlb_entry(struct mmu_gather *tlb, pte_t *ptep,
26 unsigned long address)
27 {
28 if (tlb->start > address)
29 tlb->start = address;
30 if (tlb->end < address + PAGE_SIZE)
31 tlb->end = address + PAGE_SIZE;
32 }
33
init_tlb_gather(struct mmu_gather * tlb)34 static inline void init_tlb_gather(struct mmu_gather *tlb)
35 {
36 tlb->need_flush = 0;
37
38 tlb->start = TASK_SIZE;
39 tlb->end = 0;
40
41 if (tlb->fullmm) {
42 tlb->start = 0;
43 tlb->end = TASK_SIZE;
44 }
45 }
46
47 static inline void
tlb_gather_mmu(struct mmu_gather * tlb,struct mm_struct * mm,unsigned int full_mm_flush)48 tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned int full_mm_flush)
49 {
50 tlb->mm = mm;
51 tlb->fullmm = full_mm_flush;
52
53 init_tlb_gather(tlb);
54 }
55
56 extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
57 unsigned long end);
58
59 static inline void
tlb_flush_mmu(struct mmu_gather * tlb)60 tlb_flush_mmu(struct mmu_gather *tlb)
61 {
62 if (!tlb->need_flush)
63 return;
64
65 flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end);
66 init_tlb_gather(tlb);
67 }
68
69 /* tlb_finish_mmu
70 * Called at the end of the shootdown operation to free up any resources
71 * that were required.
72 */
73 static inline void
tlb_finish_mmu(struct mmu_gather * tlb,unsigned long start,unsigned long end)74 tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
75 {
76 tlb_flush_mmu(tlb);
77
78 /* keep the page table cache within bounds */
79 check_pgt_cache();
80 }
81
82 /* tlb_remove_page
83 * Must perform the equivalent to __free_pte(pte_get_and_clear(ptep)),
84 * while handling the additional races in SMP caused by other CPUs
85 * caching valid mappings in their TLBs.
86 */
__tlb_remove_page(struct mmu_gather * tlb,struct page * page)87 static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
88 {
89 tlb->need_flush = 1;
90 free_page_and_swap_cache(page);
91 return 1; /* avoid calling tlb_flush_mmu */
92 }
93
tlb_remove_page(struct mmu_gather * tlb,struct page * page)94 static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
95 {
96 __tlb_remove_page(tlb, page);
97 }
98
99 /**
100 * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
101 *
102 * Record the fact that pte's were really umapped in ->need_flush, so we can
103 * later optimise away the tlb invalidate. This helps when userspace is
104 * unmapping already-unmapped pages, which happens quite a lot.
105 */
106 #define tlb_remove_tlb_entry(tlb, ptep, address) \
107 do { \
108 tlb->need_flush = 1; \
109 __tlb_remove_tlb_entry(tlb, ptep, address); \
110 } while (0)
111
112 #define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr)
113
114 #define pud_free_tlb(tlb, pudp, addr) __pud_free_tlb(tlb, pudp, addr)
115
116 #define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr)
117
118 #define tlb_migrate_finish(mm) do {} while (0)
119
120 #endif
121