1 #ifndef _ASM_POWERPC_PAGE_H
2 #define _ASM_POWERPC_PAGE_H
5 * Copyright (C) 2001,2005 IBM Corporation.
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.
14 #include <linux/types.h>
16 #include <asm/types.h>
18 #include <asm/asm-compat.h>
19 #include <asm/kdump.h>
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.
27 #if defined(CONFIG_PPC_256K_PAGES)
29 #elif defined(CONFIG_PPC_64K_PAGES)
31 #elif defined(CONFIG_PPC_16K_PAGES)
37 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT)
40 #ifdef CONFIG_HUGETLB_PAGE
41 extern unsigned int HPAGE_SHIFT;
43 #define HPAGE_SHIFT PAGE_SHIFT
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)
51 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */
52 #define __HAVE_ARCH_GATE_AREA 1
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)
59 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
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_.
65 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET.
67 * PAGE_OFFSET is the virtual address of the start of lowmem.
69 * PHYSICAL_START is the physical address of the start of the kernel.
71 * MEMORY_START is the physical address of the start of lowmem.
73 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on
74 * ppc32 and based on how they are set we determine MEMORY_START.
76 * For the linear mapping the following equation should be true:
77 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START
79 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START
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
85 * If you want to know something's offset from the start of the kernel you
86 * should subtract KERNELBASE.
88 * If you want to test if something's a kernel address, use is_kernel_addr().
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))
95 #if defined(CONFIG_RELOCATABLE)
98 extern phys_addr_t memstart_addr;
99 extern phys_addr_t kernstart_addr;
101 #define PHYSICAL_START kernstart_addr
103 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START)
107 #define MEMORY_START 0UL
108 #elif defined(CONFIG_RELOCATABLE)
109 #define MEMORY_START memstart_addr
111 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
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)
119 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
120 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
122 #ifdef CONFIG_PPC_BOOK3S_64
124 * On hash the vmalloc and other regions alias to the kernel region when passed
125 * through __pa(), which virt_to_pfn() uses. That means virt_addr_valid() can
126 * return true for some vmalloc addresses, which is incorrect. So explicitly
127 * check that the address is in the kernel region.
129 #define virt_addr_valid(kaddr) (REGION_ID(kaddr) == KERNEL_REGION_ID && \
130 pfn_valid(__pa(kaddr) >> PAGE_SHIFT))
132 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
136 * On Book-E parts we need __va to parse the device tree and we can't
137 * determine MEMORY_START until then. However we can determine PHYSICAL_START
138 * from information at hand (program counter, TLB lookup).
140 * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use
141 * the other definitions for __va & __pa.
144 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) - PHYSICAL_START + KERNELBASE))
145 #define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE)
149 * gcc miscompiles (unsigned long)(&static_var) - PAGE_OFFSET
150 * with -mcmodel=medium, so we use & and | instead of - and + on 64-bit.
152 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) | PAGE_OFFSET))
153 #define __pa(x) ((unsigned long)(x) & 0x0fffffffffffffffUL)
155 #else /* 32-bit, non book E */
156 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
157 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START)
162 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
163 * and needs to be executable. This means the whole heap ends
164 * up being executable.
166 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \
167 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
169 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \
170 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
173 #include <asm/page_64.h>
175 #include <asm/page_32.h>
178 /* align addr on a size boundary - adjust address up/down if needed */
179 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
180 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1)))
182 /* align addr on a size boundary - adjust address up if needed */
183 #define _ALIGN(addr,size) _ALIGN_UP(addr,size)
186 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
187 * "kernelness", use is_kernel_addr() - it should do what you want.
189 #ifdef CONFIG_PPC_BOOK3E_64
190 #define is_kernel_addr(x) ((x) >= 0x8000000000000000ul)
192 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET)
196 * Use the top bit of the higher-level page table entries to indicate whether
197 * the entries we point to contain hugepages. This works because we know that
198 * the page tables live in kernel space. If we ever decide to support having
199 * page tables at arbitrary addresses, this breaks and will have to change.
202 #define PD_HUGE 0x8000000000000000
204 #define PD_HUGE 0x80000000
208 * Some number of bits at the level of the page table that points to
209 * a hugepte are used to encode the size. This masks those bits.
211 #define HUGEPD_SHIFT_MASK 0x3f
215 #undef STRICT_MM_TYPECHECKS
217 #ifdef STRICT_MM_TYPECHECKS
218 /* These are used to make use of C type-checking. */
221 typedef struct { pte_basic_t pte; } pte_t;
222 #define pte_val(x) ((x).pte)
223 #define __pte(x) ((pte_t) { (x) })
225 /* 64k pages additionally define a bigger "real PTE" type that gathers
226 * the "second half" part of the PTE for pseudo 64k pages
228 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
229 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
231 typedef struct { pte_t pte; } real_pte_t;
236 typedef struct { unsigned long pmd; } pmd_t;
237 #define pmd_val(x) ((x).pmd)
238 #define __pmd(x) ((pmd_t) { (x) })
240 /* PUD level exusts only on 4k pages */
241 #ifndef CONFIG_PPC_64K_PAGES
242 typedef struct { unsigned long pud; } pud_t;
243 #define pud_val(x) ((x).pud)
244 #define __pud(x) ((pud_t) { (x) })
245 #endif /* !CONFIG_PPC_64K_PAGES */
246 #endif /* CONFIG_PPC64 */
249 typedef struct { unsigned long pgd; } pgd_t;
250 #define pgd_val(x) ((x).pgd)
251 #define __pgd(x) ((pgd_t) { (x) })
253 /* Page protection bits */
254 typedef struct { unsigned long pgprot; } pgprot_t;
255 #define pgprot_val(x) ((x).pgprot)
256 #define __pgprot(x) ((pgprot_t) { (x) })
261 * .. while these make it easier on the compiler
264 typedef pte_basic_t pte_t;
265 #define pte_val(x) (x)
268 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
269 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
271 typedef pte_t real_pte_t;
276 typedef unsigned long pmd_t;
277 #define pmd_val(x) (x)
280 #ifndef CONFIG_PPC_64K_PAGES
281 typedef unsigned long pud_t;
282 #define pud_val(x) (x)
284 #endif /* !CONFIG_PPC_64K_PAGES */
285 #endif /* CONFIG_PPC64 */
287 typedef unsigned long pgd_t;
288 #define pgd_val(x) (x)
289 #define pgprot_val(x) (x)
291 typedef unsigned long pgprot_t;
293 #define __pgprot(x) (x)
297 typedef struct { signed long pd; } hugepd_t;
299 #ifdef CONFIG_HUGETLB_PAGE
300 static inline int hugepd_ok(hugepd_t hpd)
305 #define is_hugepd(pdep) (hugepd_ok(*((hugepd_t *)(pdep))))
306 #else /* CONFIG_HUGETLB_PAGE */
307 #define is_hugepd(pdep) 0
308 #endif /* CONFIG_HUGETLB_PAGE */
311 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
312 extern void copy_user_page(void *to, void *from, unsigned long vaddr,
314 extern int page_is_ram(unsigned long pfn);
316 #ifdef CONFIG_PPC_SMLPAR
317 void arch_free_page(struct page *page, int order);
318 #define HAVE_ARCH_FREE_PAGE
321 struct vm_area_struct;
323 typedef struct page *pgtable_t;
325 #include <asm-generic/memory_model.h>
326 #endif /* __ASSEMBLY__ */
328 #endif /* _ASM_POWERPC_PAGE_H */