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-rw-r--r--arch/metag/mm/highmem.c122
1 files changed, 0 insertions, 122 deletions
diff --git a/arch/metag/mm/highmem.c b/arch/metag/mm/highmem.c
deleted file mode 100644
index 83527fc7c8a7..000000000000
--- a/arch/metag/mm/highmem.c
+++ /dev/null
@@ -1,122 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <linux/export.h>
-#include <linux/highmem.h>
-#include <linux/sched.h>
-#include <linux/smp.h>
-#include <linux/interrupt.h>
-#include <asm/fixmap.h>
-#include <asm/tlbflush.h>
-
-static pte_t *kmap_pte;
-
-unsigned long highstart_pfn, highend_pfn;
-
-void *kmap(struct page *page)
-{
- might_sleep();
- if (!PageHighMem(page))
- return page_address(page);
- return kmap_high(page);
-}
-EXPORT_SYMBOL(kmap);
-
-void kunmap(struct page *page)
-{
- BUG_ON(in_interrupt());
- if (!PageHighMem(page))
- return;
- kunmap_high(page);
-}
-EXPORT_SYMBOL(kunmap);
-
-/*
- * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
- * no global lock is needed and because the kmap code must perform a global TLB
- * invalidation when the kmap pool wraps.
- *
- * However when holding an atomic kmap is is not legal to sleep, so atomic
- * kmaps are appropriate for short, tight code paths only.
- */
-
-void *kmap_atomic(struct page *page)
-{
- enum fixed_addresses idx;
- unsigned long vaddr;
- int type;
-
- preempt_disable();
- pagefault_disable();
- if (!PageHighMem(page))
- return page_address(page);
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
- set_pte(kmap_pte - idx, mk_pte(page, PAGE_KERNEL));
-
- return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic);
-
-void __kunmap_atomic(void *kvaddr)
-{
- unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
- int idx, type;
-
- if (kvaddr >= (void *)FIXADDR_START) {
- type = kmap_atomic_idx();
- idx = type + KM_TYPE_NR * smp_processor_id();
-
- /*
- * Force other mappings to Oops if they'll try to access this
- * pte without first remap it. Keeping stale mappings around
- * is a bad idea also, in case the page changes cacheability
- * attributes or becomes a protected page in a hypervisor.
- */
- pte_clear(&init_mm, vaddr, kmap_pte-idx);
- flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
-
- kmap_atomic_idx_pop();
- }
-
- pagefault_enable();
- preempt_enable();
-}
-EXPORT_SYMBOL(__kunmap_atomic);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
- enum fixed_addresses idx;
- unsigned long vaddr;
- int type;
-
- preempt_disable();
- pagefault_disable();
-
- type = kmap_atomic_idx_push();
- idx = type + KM_TYPE_NR * smp_processor_id();
- vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
- BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
- set_pte(kmap_pte - idx, pfn_pte(pfn, PAGE_KERNEL));
- flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
-
- return (void *)vaddr;
-}
-
-void __init kmap_init(void)
-{
- unsigned long kmap_vstart;
-
- /* cache the first kmap pte */
- kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
- kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
-}