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-rw-r--r--arch/powerpc/include/asm/page.h225
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diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
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+++ b/arch/powerpc/include/asm/page.h
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+#ifndef _ASM_POWERPC_PAGE_H
+#define _ASM_POWERPC_PAGE_H
+
+/*
+ * Copyright (C) 2001,2005 IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <asm/asm-compat.h>
+#include <asm/kdump.h>
+#include <asm/types.h>
+
+/*
+ * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software
+ * page size. When using 64K pages however, whether we are really supporting
+ * 64K pages in HW or not is irrelevant to those definitions.
+ */
+#ifdef CONFIG_PPC_64K_PAGES
+#define PAGE_SHIFT 16
+#else
+#define PAGE_SHIFT 12
+#endif
+
+#define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT)
+
+/* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */
+#define __HAVE_ARCH_GATE_AREA 1
+
+/*
+ * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
+ * assign PAGE_MASK to a larger type it gets extended the way we want
+ * (i.e. with 1s in the high bits)
+ */
+#define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
+
+/*
+ * KERNELBASE is the virtual address of the start of the kernel, it's often
+ * the same as PAGE_OFFSET, but _might not be_.
+ *
+ * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET.
+ *
+ * PAGE_OFFSET is the virtual address of the start of lowmem.
+ *
+ * PHYSICAL_START is the physical address of the start of the kernel.
+ *
+ * MEMORY_START is the physical address of the start of lowmem.
+ *
+ * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on
+ * ppc32 and based on how they are set we determine MEMORY_START.
+ *
+ * For the linear mapping the following equation should be true:
+ * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START
+ *
+ * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START
+ *
+ * There are two was to determine a physical address from a virtual one:
+ * va = pa + PAGE_OFFSET - MEMORY_START
+ * va = pa + KERNELBASE - PHYSICAL_START
+ *
+ * If you want to know something's offset from the start of the kernel you
+ * should subtract KERNELBASE.
+ *
+ * If you want to test if something's a kernel address, use is_kernel_addr().
+ */
+
+#define KERNELBASE ASM_CONST(CONFIG_KERNEL_START)
+#define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET)
+#define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START))
+
+#if defined(CONFIG_RELOCATABLE) && defined(CONFIG_FLATMEM)
+#ifndef __ASSEMBLY__
+extern phys_addr_t memstart_addr;
+extern phys_addr_t kernstart_addr;
+#endif
+#define PHYSICAL_START kernstart_addr
+#define MEMORY_START memstart_addr
+#else
+#define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START)
+#define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
+#endif
+
+#ifdef CONFIG_FLATMEM
+#define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT)
+#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr))
+#endif
+
+#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
+#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+
+#define __va(x) ((void *)((unsigned long)(x) - PHYSICAL_START + KERNELBASE))
+#define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE)
+
+/*
+ * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
+ * and needs to be executable. This means the whole heap ends
+ * up being executable.
+ */
+#define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \
+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \
+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#ifdef __powerpc64__
+#include <asm/page_64.h>
+#else
+#include <asm/page_32.h>
+#endif
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr,size) _ALIGN_UP(addr,size)
+
+/*
+ * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
+ * "kernelness", use is_kernel_addr() - it should do what you want.
+ */
+#define is_kernel_addr(x) ((x) >= PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#undef STRICT_MM_TYPECHECKS
+
+#ifdef STRICT_MM_TYPECHECKS
+/* These are used to make use of C type-checking. */
+
+/* PTE level */
+typedef struct { pte_basic_t pte; } pte_t;
+#define pte_val(x) ((x).pte)
+#define __pte(x) ((pte_t) { (x) })
+
+/* 64k pages additionally define a bigger "real PTE" type that gathers
+ * the "second half" part of the PTE for pseudo 64k pages
+ */
+#ifdef CONFIG_PPC_64K_PAGES
+typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
+#else
+typedef struct { pte_t pte; } real_pte_t;
+#endif
+
+/* PMD level */
+#ifdef CONFIG_PPC64
+typedef struct { unsigned long pmd; } pmd_t;
+#define pmd_val(x) ((x).pmd)
+#define __pmd(x) ((pmd_t) { (x) })
+
+/* PUD level exusts only on 4k pages */
+#ifndef CONFIG_PPC_64K_PAGES
+typedef struct { unsigned long pud; } pud_t;
+#define pud_val(x) ((x).pud)
+#define __pud(x) ((pud_t) { (x) })
+#endif /* !CONFIG_PPC_64K_PAGES */
+#endif /* CONFIG_PPC64 */
+
+/* PGD level */
+typedef struct { unsigned long pgd; } pgd_t;
+#define pgd_val(x) ((x).pgd)
+#define __pgd(x) ((pgd_t) { (x) })
+
+/* Page protection bits */
+typedef struct { unsigned long pgprot; } pgprot_t;
+#define pgprot_val(x) ((x).pgprot)
+#define __pgprot(x) ((pgprot_t) { (x) })
+
+#else
+
+/*
+ * .. while these make it easier on the compiler
+ */
+
+typedef pte_basic_t pte_t;
+#define pte_val(x) (x)
+#define __pte(x) (x)
+
+#ifdef CONFIG_PPC_64K_PAGES
+typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
+#else
+typedef unsigned long real_pte_t;
+#endif
+
+
+#ifdef CONFIG_PPC64
+typedef unsigned long pmd_t;
+#define pmd_val(x) (x)
+#define __pmd(x) (x)
+
+#ifndef CONFIG_PPC_64K_PAGES
+typedef unsigned long pud_t;
+#define pud_val(x) (x)
+#define __pud(x) (x)
+#endif /* !CONFIG_PPC_64K_PAGES */
+#endif /* CONFIG_PPC64 */
+
+typedef unsigned long pgd_t;
+#define pgd_val(x) (x)
+#define pgprot_val(x) (x)
+
+typedef unsigned long pgprot_t;
+#define __pgd(x) (x)
+#define __pgprot(x) (x)
+
+#endif
+
+struct page;
+extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
+extern void copy_user_page(void *to, void *from, unsigned long vaddr,
+ struct page *p);
+extern int page_is_ram(unsigned long pfn);
+
+struct vm_area_struct;
+
+typedef struct page *pgtable_t;
+
+#include <asm-generic/memory_model.h>
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_PAGE_H */