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-rw-r--r--include/asm-sparc/highmem.h81
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diff --git a/include/asm-sparc/highmem.h b/include/asm-sparc/highmem.h
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+/*
+ * highmem.h: virtual kernel memory mappings for high memory
+ *
+ * Used in CONFIG_HIGHMEM systems for memory pages which
+ * are not addressable by direct kernel virtual addresses.
+ *
+ * Copyright (C) 1999 Gerhard Wichert, Siemens AG
+ * Gerhard.Wichert@pdb.siemens.de
+ *
+ *
+ * Redesigned the x86 32-bit VM architecture to deal with
+ * up to 16 Terrabyte physical memory. With current x86 CPUs
+ * we now support up to 64 Gigabytes physical RAM.
+ *
+ * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
+ */
+
+#ifndef _ASM_HIGHMEM_H
+#define _ASM_HIGHMEM_H
+
+#ifdef __KERNEL__
+
+#include <linux/interrupt.h>
+#include <asm/fixmap.h>
+#include <asm/vaddrs.h>
+#include <asm/kmap_types.h>
+#include <asm/pgtable.h>
+
+/* declarations for highmem.c */
+extern unsigned long highstart_pfn, highend_pfn;
+
+extern pte_t *kmap_pte;
+extern pgprot_t kmap_prot;
+extern pte_t *pkmap_page_table;
+
+extern void kmap_init(void) __init;
+
+/*
+ * Right now we initialize only a single pte table. It can be extended
+ * easily, subsequent pte tables have to be allocated in one physical
+ * chunk of RAM. Currently the simplest way to do this is to align the
+ * pkmap region on a pagetable boundary (4MB).
+ */
+#define LAST_PKMAP 1024
+#define PKMAP_SIZE (LAST_PKMAP << PAGE_SHIFT)
+#define PKMAP_BASE PMD_ALIGN(SRMMU_NOCACHE_VADDR + (SRMMU_MAX_NOCACHE_PAGES << PAGE_SHIFT))
+
+#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
+#define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
+#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
+
+#define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))
+
+extern void *kmap_high(struct page *page);
+extern void kunmap_high(struct page *page);
+
+static inline void *kmap(struct page *page)
+{
+ BUG_ON(in_interrupt());
+ if (!PageHighMem(page))
+ return page_address(page);
+ return kmap_high(page);
+}
+
+static inline void kunmap(struct page *page)
+{
+ BUG_ON(in_interrupt());
+ if (!PageHighMem(page))
+ return;
+ kunmap_high(page);
+}
+
+extern void *kmap_atomic(struct page *page, enum km_type type);
+extern void kunmap_atomic(void *kvaddr, enum km_type type);
+extern struct page *kmap_atomic_to_page(void *vaddr);
+
+#define flush_cache_kmaps() flush_cache_all()
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_HIGHMEM_H */