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 regular PPC32 page size is 4K (but we support 4K/16K/64K pages 23 * on PPC44x). For PPC64 we support either 4K or 64K software 24 * page size. When using 64K pages however, whether we are really supporting 25 * 64K pages in HW or not is irrelevant to those definitions. 26 */ 27 #if defined(CONFIG_PPC_64K_PAGES) 28 #define PAGE_SHIFT 16 29 #elif defined(CONFIG_PPC_16K_PAGES) 30 #define PAGE_SHIFT 14 31 #else 32 #define PAGE_SHIFT 12 33 #endif 34 35 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) 36 37 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ 38 #define __HAVE_ARCH_GATE_AREA 1 39 40 /* 41 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we 42 * assign PAGE_MASK to a larger type it gets extended the way we want 43 * (i.e. with 1s in the high bits) 44 */ 45 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) 46 47 /* 48 * KERNELBASE is the virtual address of the start of the kernel, it's often 49 * the same as PAGE_OFFSET, but _might not be_. 50 * 51 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET. 52 * 53 * PAGE_OFFSET is the virtual address of the start of lowmem. 54 * 55 * PHYSICAL_START is the physical address of the start of the kernel. 56 * 57 * MEMORY_START is the physical address of the start of lowmem. 58 * 59 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on 60 * ppc32 and based on how they are set we determine MEMORY_START. 61 * 62 * For the linear mapping the following equation should be true: 63 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START 64 * 65 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START 66 * 67 * There are two was to determine a physical address from a virtual one: 68 * va = pa + PAGE_OFFSET - MEMORY_START 69 * va = pa + KERNELBASE - PHYSICAL_START 70 * 71 * If you want to know something's offset from the start of the kernel you 72 * should subtract KERNELBASE. 73 * 74 * If you want to test if something's a kernel address, use is_kernel_addr(). 75 */ 76 77 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START) 78 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) 79 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) 80 81 #if defined(CONFIG_RELOCATABLE) 82 #ifndef __ASSEMBLY__ 83 84 extern phys_addr_t memstart_addr; 85 extern phys_addr_t kernstart_addr; 86 #endif 87 #define PHYSICAL_START kernstart_addr 88 #else 89 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) 90 #endif 91 92 #ifdef CONFIG_PPC64 93 #define MEMORY_START 0UL 94 #elif defined(CONFIG_RELOCATABLE) 95 #define MEMORY_START memstart_addr 96 #else 97 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) 98 #endif 99 100 #ifdef CONFIG_FLATMEM 101 #define ARCH_PFN_OFFSET (MEMORY_START >> PAGE_SHIFT) 102 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (ARCH_PFN_OFFSET + max_mapnr)) 103 #endif 104 105 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 106 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 107 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 108 109 #define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - MEMORY_START)) 110 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START) 111 112 /* 113 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, 114 * and needs to be executable. This means the whole heap ends 115 * up being executable. 116 */ 117 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ 118 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 119 120 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \ 121 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 122 123 #ifdef __powerpc64__ 124 #include <asm/page_64.h> 125 #else 126 #include <asm/page_32.h> 127 #endif 128 129 /* align addr on a size boundary - adjust address up/down if needed */ 130 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) 131 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) 132 133 /* align addr on a size boundary - adjust address up if needed */ 134 #define _ALIGN(addr,size) _ALIGN_UP(addr,size) 135 136 /* 137 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for 138 * "kernelness", use is_kernel_addr() - it should do what you want. 139 */ 140 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) 141 142 #ifndef __ASSEMBLY__ 143 144 #undef STRICT_MM_TYPECHECKS 145 146 #ifdef STRICT_MM_TYPECHECKS 147 /* These are used to make use of C type-checking. */ 148 149 /* PTE level */ 150 typedef struct { pte_basic_t pte; } pte_t; 151 #define pte_val(x) ((x).pte) 152 #define __pte(x) ((pte_t) { (x) }) 153 154 /* 64k pages additionally define a bigger "real PTE" type that gathers 155 * the "second half" part of the PTE for pseudo 64k pages 156 */ 157 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 158 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 159 #else 160 typedef struct { pte_t pte; } real_pte_t; 161 #endif 162 163 /* PMD level */ 164 #ifdef CONFIG_PPC64 165 typedef struct { unsigned long pmd; } pmd_t; 166 #define pmd_val(x) ((x).pmd) 167 #define __pmd(x) ((pmd_t) { (x) }) 168 169 /* PUD level exusts only on 4k pages */ 170 #ifndef CONFIG_PPC_64K_PAGES 171 typedef struct { unsigned long pud; } pud_t; 172 #define pud_val(x) ((x).pud) 173 #define __pud(x) ((pud_t) { (x) }) 174 #endif /* !CONFIG_PPC_64K_PAGES */ 175 #endif /* CONFIG_PPC64 */ 176 177 /* PGD level */ 178 typedef struct { unsigned long pgd; } pgd_t; 179 #define pgd_val(x) ((x).pgd) 180 #define __pgd(x) ((pgd_t) { (x) }) 181 182 /* Page protection bits */ 183 typedef struct { unsigned long pgprot; } pgprot_t; 184 #define pgprot_val(x) ((x).pgprot) 185 #define __pgprot(x) ((pgprot_t) { (x) }) 186 187 #else 188 189 /* 190 * .. while these make it easier on the compiler 191 */ 192 193 typedef pte_basic_t pte_t; 194 #define pte_val(x) (x) 195 #define __pte(x) (x) 196 197 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 198 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 199 #else 200 typedef pte_t real_pte_t; 201 #endif 202 203 204 #ifdef CONFIG_PPC64 205 typedef unsigned long pmd_t; 206 #define pmd_val(x) (x) 207 #define __pmd(x) (x) 208 209 #ifndef CONFIG_PPC_64K_PAGES 210 typedef unsigned long pud_t; 211 #define pud_val(x) (x) 212 #define __pud(x) (x) 213 #endif /* !CONFIG_PPC_64K_PAGES */ 214 #endif /* CONFIG_PPC64 */ 215 216 typedef unsigned long pgd_t; 217 #define pgd_val(x) (x) 218 #define pgprot_val(x) (x) 219 220 typedef unsigned long pgprot_t; 221 #define __pgd(x) (x) 222 #define __pgprot(x) (x) 223 224 #endif 225 226 struct page; 227 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); 228 extern void copy_user_page(void *to, void *from, unsigned long vaddr, 229 struct page *p); 230 extern int page_is_ram(unsigned long pfn); 231 232 struct vm_area_struct; 233 234 typedef struct page *pgtable_t; 235 236 #include <asm-generic/memory_model.h> 237 #endif /* __ASSEMBLY__ */ 238 239 #endif /* _ASM_POWERPC_PAGE_H */ 240