1 #ifndef _ASM_POWERPC_PAGE_H 2 #define _ASM_POWERPC_PAGE_H 3 4 /* 5 * Copyright (C) 2001,2005 IBM Corporation. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #include <asm/asm-compat.h> 14 #include <asm/kdump.h> 15 #include <asm/types.h> 16 17 /* 18 * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software 19 * page size. When using 64K pages however, whether we are really supporting 20 * 64K pages in HW or not is irrelevant to those definitions. 21 */ 22 #ifdef CONFIG_PPC_64K_PAGES 23 #define PAGE_SHIFT 16 24 #else 25 #define PAGE_SHIFT 12 26 #endif 27 28 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) 29 30 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ 31 #define __HAVE_ARCH_GATE_AREA 1 32 33 /* 34 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we 35 * assign PAGE_MASK to a larger type it gets extended the way we want 36 * (i.e. with 1s in the high bits) 37 */ 38 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) 39 40 /* 41 * KERNELBASE is the virtual address of the start of the kernel, it's often 42 * the same as PAGE_OFFSET, but _might not be_. 43 * 44 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET. 45 * 46 * PAGE_OFFSET is the virtual address of the start of lowmem. 47 * 48 * PHYSICAL_START is the physical address of the start of the kernel. 49 * 50 * MEMORY_START is the physical address of the start of lowmem. 51 * 52 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on 53 * ppc32 and based on how they are set we determine MEMORY_START. 54 * 55 * For the linear mapping the following equation should be true: 56 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START 57 * 58 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START 59 * 60 * There are two was to determine a physical address from a virtual one: 61 * va = pa + PAGE_OFFSET - MEMORY_START 62 * va = pa + KERNELBASE - PHYSICAL_START 63 * 64 * If you want to know something's offset from the start of the kernel you 65 * should subtract KERNELBASE. 66 * 67 * If you want to test if something's a kernel address, use is_kernel_addr(). 68 */ 69 70 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START) 71 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) 72 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) 73 74 #if defined(CONFIG_RELOCATABLE) && defined(CONFIG_FLATMEM) 75 #ifndef __ASSEMBLY__ 76 extern phys_addr_t memstart_addr; 77 extern phys_addr_t kernstart_addr; 78 #endif 79 #define PHYSICAL_START kernstart_addr 80 #define MEMORY_START memstart_addr 81 #else 82 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) 83 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) 84 #endif 85 86 #ifdef CONFIG_FLATMEM 87 #define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT) 88 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr)) 89 #endif 90 91 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 92 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 93 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 94 95 #define __va(x) ((void *)((unsigned long)(x) - PHYSICAL_START + KERNELBASE)) 96 #define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE) 97 98 /* 99 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, 100 * and needs to be executable. This means the whole heap ends 101 * up being executable. 102 */ 103 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ 104 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 105 106 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \ 107 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 108 109 #ifdef __powerpc64__ 110 #include <asm/page_64.h> 111 #else 112 #include <asm/page_32.h> 113 #endif 114 115 /* align addr on a size boundary - adjust address up/down if needed */ 116 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) 117 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) 118 119 /* align addr on a size boundary - adjust address up if needed */ 120 #define _ALIGN(addr,size) _ALIGN_UP(addr,size) 121 122 /* 123 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for 124 * "kernelness", use is_kernel_addr() - it should do what you want. 125 */ 126 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) 127 128 #ifndef __ASSEMBLY__ 129 130 #undef STRICT_MM_TYPECHECKS 131 132 #ifdef STRICT_MM_TYPECHECKS 133 /* These are used to make use of C type-checking. */ 134 135 /* PTE level */ 136 typedef struct { pte_basic_t pte; } pte_t; 137 #define pte_val(x) ((x).pte) 138 #define __pte(x) ((pte_t) { (x) }) 139 140 /* 64k pages additionally define a bigger "real PTE" type that gathers 141 * the "second half" part of the PTE for pseudo 64k pages 142 */ 143 #ifdef CONFIG_PPC_64K_PAGES 144 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 145 #else 146 typedef struct { pte_t pte; } real_pte_t; 147 #endif 148 149 /* PMD level */ 150 #ifdef CONFIG_PPC64 151 typedef struct { unsigned long pmd; } pmd_t; 152 #define pmd_val(x) ((x).pmd) 153 #define __pmd(x) ((pmd_t) { (x) }) 154 155 /* PUD level exusts only on 4k pages */ 156 #ifndef CONFIG_PPC_64K_PAGES 157 typedef struct { unsigned long pud; } pud_t; 158 #define pud_val(x) ((x).pud) 159 #define __pud(x) ((pud_t) { (x) }) 160 #endif /* !CONFIG_PPC_64K_PAGES */ 161 #endif /* CONFIG_PPC64 */ 162 163 /* PGD level */ 164 typedef struct { unsigned long pgd; } pgd_t; 165 #define pgd_val(x) ((x).pgd) 166 #define __pgd(x) ((pgd_t) { (x) }) 167 168 /* Page protection bits */ 169 typedef struct { unsigned long pgprot; } pgprot_t; 170 #define pgprot_val(x) ((x).pgprot) 171 #define __pgprot(x) ((pgprot_t) { (x) }) 172 173 #else 174 175 /* 176 * .. while these make it easier on the compiler 177 */ 178 179 typedef pte_basic_t pte_t; 180 #define pte_val(x) (x) 181 #define __pte(x) (x) 182 183 #ifdef CONFIG_PPC_64K_PAGES 184 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 185 #else 186 typedef unsigned long real_pte_t; 187 #endif 188 189 190 #ifdef CONFIG_PPC64 191 typedef unsigned long pmd_t; 192 #define pmd_val(x) (x) 193 #define __pmd(x) (x) 194 195 #ifndef CONFIG_PPC_64K_PAGES 196 typedef unsigned long pud_t; 197 #define pud_val(x) (x) 198 #define __pud(x) (x) 199 #endif /* !CONFIG_PPC_64K_PAGES */ 200 #endif /* CONFIG_PPC64 */ 201 202 typedef unsigned long pgd_t; 203 #define pgd_val(x) (x) 204 #define pgprot_val(x) (x) 205 206 typedef unsigned long pgprot_t; 207 #define __pgd(x) (x) 208 #define __pgprot(x) (x) 209 210 #endif 211 212 struct page; 213 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); 214 extern void copy_user_page(void *to, void *from, unsigned long vaddr, 215 struct page *p); 216 extern int page_is_ram(unsigned long pfn); 217 218 struct vm_area_struct; 219 220 typedef struct page *pgtable_t; 221 222 #include <asm-generic/memory_model.h> 223 #endif /* __ASSEMBLY__ */ 224 225 #endif /* _ASM_POWERPC_PAGE_H */ 226