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 #ifndef __ASSEMBLY__ 14 #include <linux/types.h> 15 #else 16 #include <asm/types.h> 17 #endif 18 #include <asm/asm-compat.h> 19 #include <asm/kdump.h> 20 21 /* 22 * On PPC32 page size is 4K. For PPC64 we support either 4K or 64K software 23 * page size. When using 64K pages however, whether we are really supporting 24 * 64K pages in HW or not is irrelevant to those definitions. 25 */ 26 #ifdef CONFIG_PPC_64K_PAGES 27 #define PAGE_SHIFT 16 28 #else 29 #define PAGE_SHIFT 12 30 #endif 31 32 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) 33 34 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ 35 #define __HAVE_ARCH_GATE_AREA 1 36 37 /* 38 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we 39 * assign PAGE_MASK to a larger type it gets extended the way we want 40 * (i.e. with 1s in the high bits) 41 */ 42 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) 43 44 /* 45 * KERNELBASE is the virtual address of the start of the kernel, it's often 46 * the same as PAGE_OFFSET, but _might not be_. 47 * 48 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET. 49 * 50 * PAGE_OFFSET is the virtual address of the start of lowmem. 51 * 52 * PHYSICAL_START is the physical address of the start of the kernel. 53 * 54 * MEMORY_START is the physical address of the start of lowmem. 55 * 56 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on 57 * ppc32 and based on how they are set we determine MEMORY_START. 58 * 59 * For the linear mapping the following equation should be true: 60 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START 61 * 62 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START 63 * 64 * There are two was to determine a physical address from a virtual one: 65 * va = pa + PAGE_OFFSET - MEMORY_START 66 * va = pa + KERNELBASE - PHYSICAL_START 67 * 68 * If you want to know something's offset from the start of the kernel you 69 * should subtract KERNELBASE. 70 * 71 * If you want to test if something's a kernel address, use is_kernel_addr(). 72 */ 73 74 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START) 75 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) 76 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) 77 78 #if defined(CONFIG_RELOCATABLE) 79 #ifndef __ASSEMBLY__ 80 81 extern phys_addr_t memstart_addr; 82 extern phys_addr_t kernstart_addr; 83 #endif 84 #define PHYSICAL_START kernstart_addr 85 #else 86 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) 87 #endif 88 89 #ifdef CONFIG_PPC64 90 #define MEMORY_START 0UL 91 #elif defined(CONFIG_RELOCATABLE) 92 #define MEMORY_START memstart_addr 93 #else 94 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) 95 #endif 96 97 #ifdef CONFIG_FLATMEM 98 #define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT) 99 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr)) 100 #endif 101 102 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 103 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 104 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 105 106 #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - MEMORY_START)) 107 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START) 108 109 /* 110 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, 111 * and needs to be executable. This means the whole heap ends 112 * up being executable. 113 */ 114 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ 115 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 116 117 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \ 118 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 119 120 #ifdef __powerpc64__ 121 #include <asm/page_64.h> 122 #else 123 #include <asm/page_32.h> 124 #endif 125 126 /* align addr on a size boundary - adjust address up/down if needed */ 127 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) 128 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) 129 130 /* align addr on a size boundary - adjust address up if needed */ 131 #define _ALIGN(addr,size) _ALIGN_UP(addr,size) 132 133 /* 134 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for 135 * "kernelness", use is_kernel_addr() - it should do what you want. 136 */ 137 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) 138 139 #ifndef __ASSEMBLY__ 140 141 #undef STRICT_MM_TYPECHECKS 142 143 #ifdef STRICT_MM_TYPECHECKS 144 /* These are used to make use of C type-checking. */ 145 146 /* PTE level */ 147 typedef struct { pte_basic_t pte; } pte_t; 148 #define pte_val(x) ((x).pte) 149 #define __pte(x) ((pte_t) { (x) }) 150 151 /* 64k pages additionally define a bigger "real PTE" type that gathers 152 * the "second half" part of the PTE for pseudo 64k pages 153 */ 154 #ifdef CONFIG_PPC_64K_PAGES 155 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 156 #else 157 typedef struct { pte_t pte; } real_pte_t; 158 #endif 159 160 /* PMD level */ 161 #ifdef CONFIG_PPC64 162 typedef struct { unsigned long pmd; } pmd_t; 163 #define pmd_val(x) ((x).pmd) 164 #define __pmd(x) ((pmd_t) { (x) }) 165 166 /* PUD level exusts only on 4k pages */ 167 #ifndef CONFIG_PPC_64K_PAGES 168 typedef struct { unsigned long pud; } pud_t; 169 #define pud_val(x) ((x).pud) 170 #define __pud(x) ((pud_t) { (x) }) 171 #endif /* !CONFIG_PPC_64K_PAGES */ 172 #endif /* CONFIG_PPC64 */ 173 174 /* PGD level */ 175 typedef struct { unsigned long pgd; } pgd_t; 176 #define pgd_val(x) ((x).pgd) 177 #define __pgd(x) ((pgd_t) { (x) }) 178 179 /* Page protection bits */ 180 typedef struct { unsigned long pgprot; } pgprot_t; 181 #define pgprot_val(x) ((x).pgprot) 182 #define __pgprot(x) ((pgprot_t) { (x) }) 183 184 #else 185 186 /* 187 * .. while these make it easier on the compiler 188 */ 189 190 typedef pte_basic_t pte_t; 191 #define pte_val(x) (x) 192 #define __pte(x) (x) 193 194 #ifdef CONFIG_PPC_64K_PAGES 195 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 196 #else 197 typedef unsigned long real_pte_t; 198 #endif 199 200 201 #ifdef CONFIG_PPC64 202 typedef unsigned long pmd_t; 203 #define pmd_val(x) (x) 204 #define __pmd(x) (x) 205 206 #ifndef CONFIG_PPC_64K_PAGES 207 typedef unsigned long pud_t; 208 #define pud_val(x) (x) 209 #define __pud(x) (x) 210 #endif /* !CONFIG_PPC_64K_PAGES */ 211 #endif /* CONFIG_PPC64 */ 212 213 typedef unsigned long pgd_t; 214 #define pgd_val(x) (x) 215 #define pgprot_val(x) (x) 216 217 typedef unsigned long pgprot_t; 218 #define __pgd(x) (x) 219 #define __pgprot(x) (x) 220 221 #endif 222 223 struct page; 224 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); 225 extern void copy_user_page(void *to, void *from, unsigned long vaddr, 226 struct page *p); 227 extern int page_is_ram(unsigned long pfn); 228 229 struct vm_area_struct; 230 231 typedef struct page *pgtable_t; 232 233 #include <asm-generic/memory_model.h> 234 #endif /* __ASSEMBLY__ */ 235 236 #endif /* _ASM_POWERPC_PAGE_H */ 237