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 */
17struct 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
25static 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
34static 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
47static inline void
48tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, unsigned long start, unsigned long end)
49{
50	tlb->mm = mm;
51	tlb->start = start;
52	tlb->end = end;
53	tlb->fullmm = !(start | (end+1));
54
55	init_tlb_gather(tlb);
56}
57
58extern void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
59			       unsigned long end);
60
61static inline void
62tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
63{
64	flush_tlb_mm_range(tlb->mm, tlb->start, tlb->end);
65}
66
67static inline void
68tlb_flush_mmu_free(struct mmu_gather *tlb)
69{
70	init_tlb_gather(tlb);
71}
72
73static inline void
74tlb_flush_mmu(struct mmu_gather *tlb)
75{
76	if (!tlb->need_flush)
77		return;
78
79	tlb_flush_mmu_tlbonly(tlb);
80	tlb_flush_mmu_free(tlb);
81}
82
83/* tlb_finish_mmu
84 *	Called at the end of the shootdown operation to free up any resources
85 *	that were required.
86 */
87static inline void
88tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
89{
90	tlb_flush_mmu(tlb);
91
92	/* keep the page table cache within bounds */
93	check_pgt_cache();
94}
95
96/* tlb_remove_page
97 *	Must perform the equivalent to __free_pte(pte_get_and_clear(ptep)),
98 *	while handling the additional races in SMP caused by other CPUs
99 *	caching valid mappings in their TLBs.
100 */
101static inline int __tlb_remove_page(struct mmu_gather *tlb, struct page *page)
102{
103	tlb->need_flush = 1;
104	free_page_and_swap_cache(page);
105	return 1; /* avoid calling tlb_flush_mmu */
106}
107
108static inline void tlb_remove_page(struct mmu_gather *tlb, struct page *page)
109{
110	__tlb_remove_page(tlb, page);
111}
112
113/**
114 * tlb_remove_tlb_entry - remember a pte unmapping for later tlb invalidation.
115 *
116 * Record the fact that pte's were really umapped in ->need_flush, so we can
117 * later optimise away the tlb invalidate.   This helps when userspace is
118 * unmapping already-unmapped pages, which happens quite a lot.
119 */
120#define tlb_remove_tlb_entry(tlb, ptep, address)		\
121	do {							\
122		tlb->need_flush = 1;				\
123		__tlb_remove_tlb_entry(tlb, ptep, address);	\
124	} while (0)
125
126#define pte_free_tlb(tlb, ptep, addr) __pte_free_tlb(tlb, ptep, addr)
127
128#define pud_free_tlb(tlb, pudp, addr) __pud_free_tlb(tlb, pudp, addr)
129
130#define pmd_free_tlb(tlb, pmdp, addr) __pmd_free_tlb(tlb, pmdp, addr)
131
132#define tlb_migrate_finish(mm) do {} while (0)
133
134#endif
135