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-rw-r--r--arch/arm/mm/minicache.c73
1 files changed, 0 insertions, 73 deletions
diff --git a/arch/arm/mm/minicache.c b/arch/arm/mm/minicache.c
index dedf2ab01b2..e69de29bb2d 100644
--- a/arch/arm/mm/minicache.c
+++ b/arch/arm/mm/minicache.c
@@ -1,73 +0,0 @@
-/*
- * linux/arch/arm/mm/minicache.c
- *
- * Copyright (C) 2001 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.
- *
- * This handles the mini data cache, as found on SA11x0 and XScale
- * processors. When we copy a user page page, we map it in such a way
- * that accesses to this page will not touch the main data cache, but
- * will be cached in the mini data cache. This prevents us thrashing
- * the main data cache on page faults.
- */
-#include <linux/init.h>
-#include <linux/mm.h>
-
-#include <asm/page.h>
-#include <asm/pgtable.h>
-#include <asm/tlbflush.h>
-
-/*
- * 0xffff8000 to 0xffffffff is reserved for any ARM architecture
- * specific hacks for copying pages efficiently.
- */
-#define minicache_address (0xffff8000)
-#define minicache_pgprot __pgprot(L_PTE_PRESENT | L_PTE_YOUNG | \
- L_PTE_CACHEABLE)
-
-static pte_t *minicache_pte;
-
-/*
- * Note that this is intended to be called only from the copy_user_page
- * asm code; anything else will require special locking to prevent the
- * mini-cache space being re-used. (Note: probably preempt unsafe).
- *
- * We rely on the fact that the minicache is 2K, and we'll be pushing
- * 4K of data through it, so we don't actually have to specifically
- * flush the minicache when we change the mapping.
- *
- * Note also: assert(PAGE_OFFSET <= virt < high_memory).
- * Unsafe: preempt, kmap.
- */
-unsigned long map_page_minicache(unsigned long virt)
-{
- set_pte(minicache_pte, pfn_pte(__pa(virt) >> PAGE_SHIFT, minicache_pgprot));
- flush_tlb_kernel_page(minicache_address);
-
- return minicache_address;
-}
-
-static int __init minicache_init(void)
-{
- pgd_t *pgd;
- pmd_t *pmd;
-
- spin_lock(&init_mm.page_table_lock);
-
- pgd = pgd_offset_k(minicache_address);
- pmd = pmd_alloc(&init_mm, pgd, minicache_address);
- if (!pmd)
- BUG();
- minicache_pte = pte_alloc_kernel(&init_mm, pmd, minicache_address);
- if (!minicache_pte)
- BUG();
-
- spin_unlock(&init_mm.page_table_lock);
-
- return 0;
-}
-
-core_initcall(minicache_init);