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/256K 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_256K_PAGES) 28 #define PAGE_SHIFT 18 29 #elif defined(CONFIG_PPC_64K_PAGES) 30 #define PAGE_SHIFT 16 31 #elif defined(CONFIG_PPC_16K_PAGES) 32 #define PAGE_SHIFT 14 33 #else 34 #define PAGE_SHIFT 12 35 #endif 36 37 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT) 38 39 #ifndef __ASSEMBLY__ 40 #ifdef CONFIG_HUGETLB_PAGE 41 extern unsigned int HPAGE_SHIFT; 42 #else 43 #define HPAGE_SHIFT PAGE_SHIFT 44 #endif 45 #define HPAGE_SIZE ((1UL) << HPAGE_SHIFT) 46 #define HPAGE_MASK (~(HPAGE_SIZE - 1)) 47 #define HUGETLB_PAGE_ORDER (HPAGE_SHIFT - PAGE_SHIFT) 48 #define HUGE_MAX_HSTATE (MMU_PAGE_COUNT-1) 49 #endif 50 51 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */ 52 #define __HAVE_ARCH_GATE_AREA 1 53 54 /* 55 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we 56 * assign PAGE_MASK to a larger type it gets extended the way we want 57 * (i.e. with 1s in the high bits) 58 */ 59 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1)) 60 61 /* 62 * KERNELBASE is the virtual address of the start of the kernel, it's often 63 * the same as PAGE_OFFSET, but _might not be_. 64 * 65 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET. 66 * 67 * PAGE_OFFSET is the virtual address of the start of lowmem. 68 * 69 * PHYSICAL_START is the physical address of the start of the kernel. 70 * 71 * MEMORY_START is the physical address of the start of lowmem. 72 * 73 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on 74 * ppc32 and based on how they are set we determine MEMORY_START. 75 * 76 * For the linear mapping the following equation should be true: 77 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START 78 * 79 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START 80 * 81 * There are two was to determine a physical address from a virtual one: 82 * va = pa + PAGE_OFFSET - MEMORY_START 83 * va = pa + KERNELBASE - PHYSICAL_START 84 * 85 * If you want to know something's offset from the start of the kernel you 86 * should subtract KERNELBASE. 87 * 88 * If you want to test if something's a kernel address, use is_kernel_addr(). 89 */ 90 91 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START) 92 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET) 93 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START)) 94 95 #if defined(CONFIG_RELOCATABLE) 96 #ifndef __ASSEMBLY__ 97 98 extern phys_addr_t memstart_addr; 99 extern phys_addr_t kernstart_addr; 100 #endif 101 #define PHYSICAL_START kernstart_addr 102 #else 103 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START) 104 #endif 105 106 #ifdef CONFIG_PPC64 107 #define MEMORY_START 0UL 108 #elif defined(CONFIG_RELOCATABLE) 109 #define MEMORY_START memstart_addr 110 #else 111 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE) 112 #endif 113 114 #ifdef CONFIG_FLATMEM 115 #define ARCH_PFN_OFFSET ((unsigned long)(MEMORY_START >> PAGE_SHIFT)) 116 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr) 117 #endif 118 119 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 120 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 121 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT) 122 123 /* 124 * On Book-E parts we need __va to parse the device tree and we can't 125 * determine MEMORY_START until then. However we can determine PHYSICAL_START 126 * from information at hand (program counter, TLB lookup). 127 * 128 * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use 129 * the other definitions for __va & __pa. 130 */ 131 #ifdef CONFIG_BOOKE 132 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) - PHYSICAL_START + KERNELBASE)) 133 #define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE) 134 #else 135 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START)) 136 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START) 137 #endif 138 139 /* 140 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI, 141 * and needs to be executable. This means the whole heap ends 142 * up being executable. 143 */ 144 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \ 145 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 146 147 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \ 148 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) 149 150 #ifdef __powerpc64__ 151 #include <asm/page_64.h> 152 #else 153 #include <asm/page_32.h> 154 #endif 155 156 /* align addr on a size boundary - adjust address up/down if needed */ 157 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1))) 158 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1))) 159 160 /* align addr on a size boundary - adjust address up if needed */ 161 #define _ALIGN(addr,size) _ALIGN_UP(addr,size) 162 163 /* 164 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for 165 * "kernelness", use is_kernel_addr() - it should do what you want. 166 */ 167 #ifdef CONFIG_PPC_BOOK3E_64 168 #define is_kernel_addr(x) ((x) >= 0x8000000000000000ul) 169 #else 170 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET) 171 #endif 172 173 /* 174 * Use the top bit of the higher-level page table entries to indicate whether 175 * the entries we point to contain hugepages. This works because we know that 176 * the page tables live in kernel space. If we ever decide to support having 177 * page tables at arbitrary addresses, this breaks and will have to change. 178 */ 179 #ifdef CONFIG_PPC64 180 #define PD_HUGE 0x8000000000000000 181 #else 182 #define PD_HUGE 0x80000000 183 #endif 184 185 /* 186 * Some number of bits at the level of the page table that points to 187 * a hugepte are used to encode the size. This masks those bits. 188 */ 189 #define HUGEPD_SHIFT_MASK 0x3f 190 191 #ifndef __ASSEMBLY__ 192 193 #undef STRICT_MM_TYPECHECKS 194 195 #ifdef STRICT_MM_TYPECHECKS 196 /* These are used to make use of C type-checking. */ 197 198 /* PTE level */ 199 typedef struct { pte_basic_t pte; } pte_t; 200 #define pte_val(x) ((x).pte) 201 #define __pte(x) ((pte_t) { (x) }) 202 203 /* 64k pages additionally define a bigger "real PTE" type that gathers 204 * the "second half" part of the PTE for pseudo 64k pages 205 */ 206 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 207 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 208 #else 209 typedef struct { pte_t pte; } real_pte_t; 210 #endif 211 212 /* PMD level */ 213 #ifdef CONFIG_PPC64 214 typedef struct { unsigned long pmd; } pmd_t; 215 #define pmd_val(x) ((x).pmd) 216 #define __pmd(x) ((pmd_t) { (x) }) 217 218 /* PUD level exusts only on 4k pages */ 219 #ifndef CONFIG_PPC_64K_PAGES 220 typedef struct { unsigned long pud; } pud_t; 221 #define pud_val(x) ((x).pud) 222 #define __pud(x) ((pud_t) { (x) }) 223 #endif /* !CONFIG_PPC_64K_PAGES */ 224 #endif /* CONFIG_PPC64 */ 225 226 /* PGD level */ 227 typedef struct { unsigned long pgd; } pgd_t; 228 #define pgd_val(x) ((x).pgd) 229 #define __pgd(x) ((pgd_t) { (x) }) 230 231 /* Page protection bits */ 232 typedef struct { unsigned long pgprot; } pgprot_t; 233 #define pgprot_val(x) ((x).pgprot) 234 #define __pgprot(x) ((pgprot_t) { (x) }) 235 236 #else 237 238 /* 239 * .. while these make it easier on the compiler 240 */ 241 242 typedef pte_basic_t pte_t; 243 #define pte_val(x) (x) 244 #define __pte(x) (x) 245 246 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64) 247 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t; 248 #else 249 typedef pte_t real_pte_t; 250 #endif 251 252 253 #ifdef CONFIG_PPC64 254 typedef unsigned long pmd_t; 255 #define pmd_val(x) (x) 256 #define __pmd(x) (x) 257 258 #ifndef CONFIG_PPC_64K_PAGES 259 typedef unsigned long pud_t; 260 #define pud_val(x) (x) 261 #define __pud(x) (x) 262 #endif /* !CONFIG_PPC_64K_PAGES */ 263 #endif /* CONFIG_PPC64 */ 264 265 typedef unsigned long pgd_t; 266 #define pgd_val(x) (x) 267 #define pgprot_val(x) (x) 268 269 typedef unsigned long pgprot_t; 270 #define __pgd(x) (x) 271 #define __pgprot(x) (x) 272 273 #endif 274 275 typedef struct { signed long pd; } hugepd_t; 276 277 #ifdef CONFIG_HUGETLB_PAGE 278 static inline int hugepd_ok(hugepd_t hpd) 279 { 280 return (hpd.pd > 0); 281 } 282 283 #define is_hugepd(pdep) (hugepd_ok(*((hugepd_t *)(pdep)))) 284 #else /* CONFIG_HUGETLB_PAGE */ 285 #define is_hugepd(pdep) 0 286 #endif /* CONFIG_HUGETLB_PAGE */ 287 288 struct page; 289 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg); 290 extern void copy_user_page(void *to, void *from, unsigned long vaddr, 291 struct page *p); 292 extern int page_is_ram(unsigned long pfn); 293 294 #ifdef CONFIG_PPC_SMLPAR 295 void arch_free_page(struct page *page, int order); 296 #define HAVE_ARCH_FREE_PAGE 297 #endif 298 299 struct vm_area_struct; 300 301 typedef struct page *pgtable_t; 302 303 #include <asm-generic/memory_model.h> 304 #endif /* __ASSEMBLY__ */ 305 306 #endif /* _ASM_POWERPC_PAGE_H */ 307