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-rw-r--r--arch/arm/include/asm/tlb.h94
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/arm/include/asm/tlb.h b/arch/arm/include/asm/tlb.h
new file mode 100644
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+++ b/arch/arm/include/asm/tlb.h
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+/*
+ * arch/arm/include/asm/tlb.h
+ *
+ * Copyright (C) 2002 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Experimentation shows that on a StrongARM, it appears to be faster
+ * to use the "invalidate whole tlb" rather than "invalidate single
+ * tlb" for this.
+ *
+ * This appears true for both the process fork+exit case, as well as
+ * the munmap-large-area case.
+ */
+#ifndef __ASMARM_TLB_H
+#define __ASMARM_TLB_H
+
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+#ifndef CONFIG_MMU
+
+#include <linux/pagemap.h>
+#include <asm-generic/tlb.h>
+
+#else /* !CONFIG_MMU */
+
+#include <asm/pgalloc.h>
+
+/*
+ * TLB handling. This allows us to remove pages from the page
+ * tables, and efficiently handle the TLB issues.
+ */
+struct mmu_gather {
+ struct mm_struct *mm;
+ unsigned int fullmm;
+};
+
+DECLARE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+static inline struct mmu_gather *
+tlb_gather_mmu(struct mm_struct *mm, unsigned int full_mm_flush)
+{
+ struct mmu_gather *tlb = &get_cpu_var(mmu_gathers);
+
+ tlb->mm = mm;
+ tlb->fullmm = full_mm_flush;
+
+ return tlb;
+}
+
+static inline void
+tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
+{
+ if (tlb->fullmm)
+ flush_tlb_mm(tlb->mm);
+
+ /* keep the page table cache within bounds */
+ check_pgt_cache();
+
+ put_cpu_var(mmu_gathers);
+}
+
+#define tlb_remove_tlb_entry(tlb,ptep,address) do { } while (0)
+
+/*
+ * In the case of tlb vma handling, we can optimise these away in the
+ * case where we're doing a full MM flush. When we're doing a munmap,
+ * the vmas are adjusted to only cover the region to be torn down.
+ */
+static inline void
+tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
+{
+ if (!tlb->fullmm)
+ flush_cache_range(vma, vma->vm_start, vma->vm_end);
+}
+
+static inline void
+tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
+{
+ if (!tlb->fullmm)
+ flush_tlb_range(vma, vma->vm_start, vma->vm_end);
+}
+
+#define tlb_remove_page(tlb,page) free_page_and_swap_cache(page)
+#define pte_free_tlb(tlb, ptep) pte_free((tlb)->mm, ptep)
+#define pmd_free_tlb(tlb, pmdp) pmd_free((tlb)->mm, pmdp)
+
+#define tlb_migrate_finish(mm) do { } while (0)
+
+#endif /* CONFIG_MMU */
+#endif