2 * arch/arm/include/asm/tlb.h
4 * Copyright (C) 2002 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * Experimentation shows that on a StrongARM, it appears to be faster
11 * to use the "invalidate whole tlb" rather than "invalidate single
14 * This appears true for both the process fork+exit case, as well as
15 * the munmap-large-area case.
17 #ifndef __ASMARM_TLB_H
18 #define __ASMARM_TLB_H
20 #include <asm/cacheflush.h>
21 #include <asm/tlbflush.h>
25 #include <linux/pagemap.h>
26 #include <asm-generic/tlb.h>
28 #else /* !CONFIG_MMU */
30 #include <asm/pgalloc.h>
33 * TLB handling. This allows us to remove pages from the page
34 * tables, and efficiently handle the TLB issues.
39 unsigned long range_start
;
40 unsigned long range_end
;
43 DECLARE_PER_CPU(struct mmu_gather
, mmu_gathers
);
45 static inline struct mmu_gather
*
46 tlb_gather_mmu(struct mm_struct
*mm
, unsigned int full_mm_flush
)
48 struct mmu_gather
*tlb
= &get_cpu_var(mmu_gathers
);
51 tlb
->fullmm
= full_mm_flush
;
57 tlb_finish_mmu(struct mmu_gather
*tlb
, unsigned long start
, unsigned long end
)
60 flush_tlb_mm(tlb
->mm
);
62 /* keep the page table cache within bounds */
65 put_cpu_var(mmu_gathers
);
69 * Memorize the range for the TLB flush.
72 tlb_remove_tlb_entry(struct mmu_gather
*tlb
, pte_t
*ptep
, unsigned long addr
)
75 if (addr
< tlb
->range_start
)
76 tlb
->range_start
= addr
;
77 if (addr
+ PAGE_SIZE
> tlb
->range_end
)
78 tlb
->range_end
= addr
+ PAGE_SIZE
;
83 * In the case of tlb vma handling, we can optimise these away in the
84 * case where we're doing a full MM flush. When we're doing a munmap,
85 * the vmas are adjusted to only cover the region to be torn down.
88 tlb_start_vma(struct mmu_gather
*tlb
, struct vm_area_struct
*vma
)
91 flush_cache_range(vma
, vma
->vm_start
, vma
->vm_end
);
92 tlb
->range_start
= TASK_SIZE
;
98 tlb_end_vma(struct mmu_gather
*tlb
, struct vm_area_struct
*vma
)
100 if (!tlb
->fullmm
&& tlb
->range_end
> 0)
101 flush_tlb_range(vma
, tlb
->range_start
, tlb
->range_end
);
104 #define tlb_remove_page(tlb,page) free_page_and_swap_cache(page)
105 #define pte_free_tlb(tlb, ptep, addr) pte_free((tlb)->mm, ptep)
106 #define pmd_free_tlb(tlb, pmdp, addr) pmd_free((tlb)->mm, pmdp)
108 #define tlb_migrate_finish(mm) do { } while (0)
110 #endif /* CONFIG_MMU */