1 files changed, 102 insertions, 0 deletions

diff --git a/include/asm-arm/tlb.h b/include/asm-arm/tlb.h
new file mode 100644
index 000000000000..9bb325c54645
--- /dev/null
+++ b/include/asm-arm/tlb.h
@@ -0,0 +1,102 @@
+/*
+ *  linux/include/asm-arm/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>
+#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            freed;
+        unsigned int            fullmm;
+
+        unsigned int            flushes;
+        unsigned int            avoided_flushes;
+};
+
+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)
+{
+        int cpu = smp_processor_id();
+        struct mmu_gather *tlb = &per_cpu(mmu_gathers, cpu);
+
+        tlb->mm = mm;
+        tlb->freed = 0;
+        tlb->fullmm = full_mm_flush;
+
+        return tlb;
+}
+
+static inline void
+tlb_finish_mmu(struct mmu_gather *tlb, unsigned long start, unsigned long end)
+{
+        struct mm_struct *mm = tlb->mm;
+        unsigned long freed = tlb->freed;
+        int rss = get_mm_counter(mm, rss);
+
+        if (rss < freed)
+                freed = rss;
+        add_mm_counter(mm, rss, -freed);
+
+        if (tlb->fullmm)
+                flush_tlb_mm(mm);
+
+        /* keep the page table cache within bounds */
+        check_pgt_cache();
+}
+
+static inline unsigned int tlb_is_full_mm(struct mmu_gather *tlb)
+{
+        return tlb->fullmm;
+}
+
+#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(ptep)
+#define pmd_free_tlb(tlb,pmdp)          pmd_free(pmdp)
+
+#define tlb_migrate_finish(mm)          do { } while (0)
+
+#endif