1 files changed, 85 insertions, 0 deletions

diff --git a/include/asm-x86/highmem.h b/include/asm-x86/highmem.h
new file mode 100644
index 000000000000..13cdcd66fff2
--- /dev/null
+++ b/include/asm-x86/highmem.h
@@ -0,0 +1,85 @@
+/*
+ * 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 Terabyte 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 <linux/threads.h>
+#include <asm/kmap_types.h>
+#include <asm/tlbflush.h>
+#include <asm/paravirt.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;
+
+/*
+ * 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.
+ */
+#ifdef CONFIG_X86_PAE
+#define LAST_PKMAP 512
+#else
+#define LAST_PKMAP 1024
+#endif
+/*
+ * Ordering is:
+ *
+ * FIXADDR_TOP
+ *                      fixed_addresses
+ * FIXADDR_START
+ *                      temp fixed addresses
+ * FIXADDR_BOOT_START
+ *                      Persistent kmap area
+ * PKMAP_BASE
+ * VMALLOC_END
+ *                      Vmalloc area
+ * VMALLOC_START
+ * high_memory
+ */
+#define PKMAP_BASE ( (FIXADDR_BOOT_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK )
+#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))
+
+extern void * FASTCALL(kmap_high(struct page *page));
+extern void FASTCALL(kunmap_high(struct page *page));
+
+void *kmap(struct page *page);
+void kunmap(struct page *page);
+void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot);
+void *kmap_atomic(struct page *page, enum km_type type);
+void kunmap_atomic(void *kvaddr, enum km_type type);
+void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
+struct page *kmap_atomic_to_page(void *ptr);
+
+#ifndef CONFIG_PARAVIRT
+#define kmap_atomic_pte(page, type)     kmap_atomic(page, type)
+#endif
+
+#define flush_cache_kmaps()     do { } while (0)
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_HIGHMEM_H */