Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / microblaze / include / asm / highmem.h

diff --git a/kernel/arch/microblaze/include/asm/highmem.h b/kernel/arch/microblaze/include/asm/highmem.h
new file mode 100644 (file)
index 0000000..d046389
--- /dev/null
+++ b/kernel/arch/microblaze/include/asm/highmem.h
@@ -0,0 +1,96 @@
+/*
+ * 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/init.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+#include <asm/fixmap.h>
+
+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.
+ */
+/*
+ * We use one full pte table with 4K pages. And with 16K/64K/256K pages pte
+ * table covers enough memory (32MB/512MB/2GB resp.), so that both FIXMAP
+ * and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP
+ * in case of 16K/64K/256K page sizes.
+ */
+
+#define PKMAP_ORDER    PTE_SHIFT
+#define LAST_PKMAP     (1 << PKMAP_ORDER)
+
+#define PKMAP_BASE     ((FIXADDR_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 *kmap_high(struct page *page);
+extern void kunmap_high(struct page *page);
+extern void *kmap_atomic_prot(struct page *page, pgprot_t prot);
+extern void __kunmap_atomic(void *kvaddr);
+
+static inline void *kmap(struct page *page)
+{
+       might_sleep();
+       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);
+}
+
+static inline void *kmap_atomic(struct page *page)
+{
+       return kmap_atomic_prot(page, kmap_prot);
+}
+
+static inline struct page *kmap_atomic_to_page(void *ptr)
+{
+       unsigned long idx, vaddr = (unsigned long) ptr;
+       pte_t *pte;
+
+       if (vaddr < FIXADDR_START)
+               return virt_to_page(ptr);
+
+       idx = virt_to_fix(vaddr);
+       pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
+       return pte_page(*pte);
+}
+
+#define flush_cache_kmaps()    { flush_icache(); flush_dcache(); }
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_HIGHMEM_H */