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-rw-r--r--arch/powerpc/include/asm/page.h414
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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.
+ */
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#else
+#include <asm/types.h>
+#endif
+#include <asm/asm-compat.h>
+#include <asm/kdump.h>
+
+/*
+ * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K pages
+ * on PPC44x). 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.
+ */
+#if defined(CONFIG_PPC_256K_PAGES)
+#define PAGE_SHIFT 18
+#elif defined(CONFIG_PPC_64K_PAGES)
+#define PAGE_SHIFT 16
+#elif defined(CONFIG_PPC_16K_PAGES)
+#define PAGE_SHIFT 14
+#else
+#define PAGE_SHIFT 12
+#endif
+
+#define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT)
+
+#ifndef __ASSEMBLY__
+#ifdef CONFIG_HUGETLB_PAGE
+extern unsigned int HPAGE_SHIFT;
+#else
+#define HPAGE_SHIFT PAGE_SHIFT
+#endif
+#define HPAGE_SIZE ((1UL) << HPAGE_SHIFT)
+#define HPAGE_MASK (~(HPAGE_SIZE - 1))
+#define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT)
+#define HUGE_MAX_HSTATE (MMU_PAGE_COUNT-1)
+#endif
+
+/*
+ * 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 ways 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_NONSTATIC_KERNEL)
+#ifndef __ASSEMBLY__
+
+extern phys_addr_t memstart_addr;
+extern phys_addr_t kernstart_addr;
+
+#ifdef CONFIG_RELOCATABLE_PPC32
+extern long long virt_phys_offset;
+#endif
+
+#endif /* __ASSEMBLY__ */
+#define PHYSICAL_START kernstart_addr
+
+#else /* !CONFIG_NONSTATIC_KERNEL */
+#define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START)
+#endif
+
+/* See Description below for VIRT_PHYS_OFFSET */
+#ifdef CONFIG_RELOCATABLE_PPC32
+#define VIRT_PHYS_OFFSET virt_phys_offset
+#else
+#define VIRT_PHYS_OFFSET (KERNELBASE - PHYSICAL_START)
+#endif
+
+
+#ifdef CONFIG_PPC64
+#define MEMORY_START 0UL
+#elif defined(CONFIG_NONSTATIC_KERNEL)
+#define MEMORY_START memstart_addr
+#else
+#define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
+#endif
+
+#ifdef CONFIG_FLATMEM
+#define ARCH_PFN_OFFSET ((unsigned long)(MEMORY_START >> PAGE_SHIFT))
+#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < 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)
+
+/*
+ * On Book-E parts we need __va to parse the device tree and we can't
+ * determine MEMORY_START until then. However we can determine PHYSICAL_START
+ * from information at hand (program counter, TLB lookup).
+ *
+ * On BookE with RELOCATABLE (RELOCATABLE_PPC32)
+ *
+ * With RELOCATABLE_PPC32, we support loading the kernel at any physical
+ * address without any restriction on the page alignment.
+ *
+ * We find the runtime address of _stext and relocate ourselves based on
+ * the following calculation:
+ *
+ * virtual_base = ALIGN_DOWN(KERNELBASE,256M) +
+ * MODULO(_stext.run,256M)
+ * and create the following mapping:
+ *
+ * ALIGN_DOWN(_stext.run,256M) => ALIGN_DOWN(KERNELBASE,256M)
+ *
+ * When we process relocations, we cannot depend on the
+ * existing equation for the __va()/__pa() translations:
+ *
+ * __va(x) = (x) - PHYSICAL_START + KERNELBASE
+ *
+ * Where:
+ * PHYSICAL_START = kernstart_addr = Physical address of _stext
+ * KERNELBASE = Compiled virtual address of _stext.
+ *
+ * This formula holds true iff, kernel load address is TLB page aligned.
+ *
+ * In our case, we need to also account for the shift in the kernel Virtual
+ * address.
+ *
+ * E.g.,
+ *
+ * Let the kernel be loaded at 64MB and KERNELBASE be 0xc0000000 (same as PAGE_OFFSET).
+ * In this case, we would be mapping 0 to 0xc0000000, and kernstart_addr = 64M
+ *
+ * Now __va(1MB) = (0x100000) - (0x4000000) + 0xc0000000
+ * = 0xbc100000 , which is wrong.
+ *
+ * Rather, it should be : 0xc0000000 + 0x100000 = 0xc0100000
+ * according to our mapping.
+ *
+ * Hence we use the following formula to get the translations right:
+ *
+ * __va(x) = (x) - [ PHYSICAL_START - Effective KERNELBASE ]
+ *
+ * Where :
+ * PHYSICAL_START = dynamic load address.(kernstart_addr variable)
+ * Effective KERNELBASE = virtual_base =
+ * = ALIGN_DOWN(KERNELBASE,256M) +
+ * MODULO(PHYSICAL_START,256M)
+ *
+ * To make the cost of __va() / __pa() more light weight, we introduce
+ * a new variable virt_phys_offset, which will hold :
+ *
+ * virt_phys_offset = Effective KERNELBASE - PHYSICAL_START
+ * = ALIGN_DOWN(KERNELBASE,256M) -
+ * ALIGN_DOWN(PHYSICALSTART,256M)
+ *
+ * Hence :
+ *
+ * __va(x) = x - PHYSICAL_START + Effective KERNELBASE
+ * = x + virt_phys_offset
+ *
+ * and
+ * __pa(x) = x + PHYSICAL_START - Effective KERNELBASE
+ * = x - virt_phys_offset
+ *
+ * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use
+ * the other definitions for __va & __pa.
+ */
+#ifdef CONFIG_BOOKE
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + VIRT_PHYS_OFFSET))
+#define __pa(x) ((unsigned long)(x) - VIRT_PHYS_OFFSET)
+#else
+#ifdef CONFIG_PPC64
+/*
+ * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
+ * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
+ */
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET))
+#define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL)
+
+#else /* 32-bit, non book E */
+#define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START)
+#endif
+#endif
+
+/*
+ * 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.
+ */
+#ifdef CONFIG_PPC_BOOK3E_64
+#define is_kernel_addr(x) ((x) >= 0x8000000000000000ul)
+#else
+#define is_kernel_addr(x) ((x) >= PAGE_OFFSET)
+#endif
+
+#ifndef CONFIG_PPC_BOOK3S_64
+/*
+ * Use the top bit of the higher-level page table entries to indicate whether
+ * the entries we point to contain hugepages. This works because we know that
+ * the page tables live in kernel space. If we ever decide to support having
+ * page tables at arbitrary addresses, this breaks and will have to change.
+ */
+#ifdef CONFIG_PPC64
+#define PD_HUGE 0x8000000000000000
+#else
+#define PD_HUGE 0x80000000
+#endif
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
+/*
+ * Some number of bits at the level of the page table that points to
+ * a hugepte are used to encode the size. This masks those bits.
+ */
+#define HUGEPD_SHIFT_MASK 0x3f
+
+#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
+ */
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
+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)
+
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
+typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
+#else
+typedef pte_t 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
+
+typedef struct { signed long pd; } hugepd_t;
+
+#ifdef CONFIG_HUGETLB_PAGE
+#ifdef CONFIG_PPC_BOOK3S_64
+static inline int hugepd_ok(hugepd_t hpd)
+{
+ /*
+ * hugepd pointer, bottom two bits == 00 and next 4 bits
+ * indicate size of table
+ */
+ return (((hpd.pd & 0x3) == 0x0) && ((hpd.pd & HUGEPD_SHIFT_MASK) != 0));
+}
+#else
+static inline int hugepd_ok(hugepd_t hpd)
+{
+ return (hpd.pd > 0);
+}
+#endif
+
+#define is_hugepd(hpd) (hugepd_ok(hpd))
+#define pgd_huge pgd_huge
+int pgd_huge(pgd_t pgd);
+#else /* CONFIG_HUGETLB_PAGE */
+#define is_hugepd(pdep) 0
+#define pgd_huge(pgd) 0
+#endif /* CONFIG_HUGETLB_PAGE */
+#define __hugepd(x) ((hugepd_t) { (x) })
+
+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);
+extern int devmem_is_allowed(unsigned long pfn);
+
+#ifdef CONFIG_PPC_SMLPAR
+void arch_free_page(struct page *page, int order);
+#define HAVE_ARCH_FREE_PAGE
+#endif
+
+struct vm_area_struct;
+
+#if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC64)
+typedef pte_t *pgtable_t;
+#else
+typedef struct page *pgtable_t;
+#endif
+
+#include <asm-generic/memory_model.h>
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_PAGE_H */