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#ifdef __KERNEL__
14#include <asm/asm-compat.h>
15#include <asm/kdump.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 * To get a physical address from a virtual one you subtract PAGE_OFFSET,
47 * _not_ KERNELBASE.
48 *
49 * If you want to know something's offset from the start of the kernel you
50 * should subtract KERNELBASE.
51 *
52 * If you want to test if something's a kernel address, use is_kernel_addr().
53 */
54
55#define PAGE_OFFSET     ASM_CONST(CONFIG_KERNEL_START)
56#define KERNELBASE      (PAGE_OFFSET + PHYSICAL_START)
57
58#ifdef CONFIG_FLATMEM
59#define pfn_valid(pfn)		((pfn) < max_mapnr)
60#endif
61
62#define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
63#define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
64#define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
65
66#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
67#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET)
68
69/*
70 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
71 * and needs to be executable.  This means the whole heap ends
72 * up being executable.
73 */
74#define VM_DATA_DEFAULT_FLAGS32	(VM_READ | VM_WRITE | VM_EXEC | \
75				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
76
77#define VM_DATA_DEFAULT_FLAGS64	(VM_READ | VM_WRITE | \
78				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
79
80#ifdef __powerpc64__
81#include <asm/page_64.h>
82#else
83#include <asm/page_32.h>
84#endif
85
86/* align addr on a size boundary - adjust address up/down if needed */
87#define _ALIGN_UP(addr,size)	(((addr)+((size)-1))&(~((size)-1)))
88#define _ALIGN_DOWN(addr,size)	((addr)&(~((size)-1)))
89
90/* align addr on a size boundary - adjust address up if needed */
91#define _ALIGN(addr,size)     _ALIGN_UP(addr,size)
92
93/* to align the pointer to the (next) page boundary */
94#define PAGE_ALIGN(addr)	_ALIGN(addr, PAGE_SIZE)
95
96/*
97 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
98 * "kernelness", use is_kernel_addr() - it should do what you want.
99 */
100#define is_kernel_addr(x)	((x) >= PAGE_OFFSET)
101
102#ifndef __ASSEMBLY__
103
104#undef STRICT_MM_TYPECHECKS
105
106#ifdef STRICT_MM_TYPECHECKS
107/* These are used to make use of C type-checking. */
108
109/* PTE level */
110typedef struct { pte_basic_t pte; } pte_t;
111#define pte_val(x)	((x).pte)
112#define __pte(x)	((pte_t) { (x) })
113
114/* 64k pages additionally define a bigger "real PTE" type that gathers
115 * the "second half" part of the PTE for pseudo 64k pages
116 */
117#ifdef CONFIG_PPC_64K_PAGES
118typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
119#else
120typedef struct { pte_t pte; } real_pte_t;
121#endif
122
123/* PMD level */
124#ifdef CONFIG_PPC64
125typedef struct { unsigned long pmd; } pmd_t;
126#define pmd_val(x)	((x).pmd)
127#define __pmd(x)	((pmd_t) { (x) })
128
129/* PUD level exusts only on 4k pages */
130#ifndef CONFIG_PPC_64K_PAGES
131typedef struct { unsigned long pud; } pud_t;
132#define pud_val(x)	((x).pud)
133#define __pud(x)	((pud_t) { (x) })
134#endif /* !CONFIG_PPC_64K_PAGES */
135#endif /* CONFIG_PPC64 */
136
137/* PGD level */
138typedef struct { unsigned long pgd; } pgd_t;
139#define pgd_val(x)	((x).pgd)
140#define __pgd(x)	((pgd_t) { (x) })
141
142/* Page protection bits */
143typedef struct { unsigned long pgprot; } pgprot_t;
144#define pgprot_val(x)	((x).pgprot)
145#define __pgprot(x)	((pgprot_t) { (x) })
146
147#else
148
149/*
150 * .. while these make it easier on the compiler
151 */
152
153typedef pte_basic_t pte_t;
154#define pte_val(x)	(x)
155#define __pte(x)	(x)
156
157#ifdef CONFIG_PPC_64K_PAGES
158typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
159#else
160typedef unsigned long real_pte_t;
161#endif
162
163
164#ifdef CONFIG_PPC64
165typedef unsigned long pmd_t;
166#define pmd_val(x)	(x)
167#define __pmd(x)	(x)
168
169#ifndef CONFIG_PPC_64K_PAGES
170typedef unsigned long pud_t;
171#define pud_val(x)	(x)
172#define __pud(x)	(x)
173#endif /* !CONFIG_PPC_64K_PAGES */
174#endif /* CONFIG_PPC64 */
175
176typedef unsigned long pgd_t;
177#define pgd_val(x)	(x)
178#define pgprot_val(x)	(x)
179
180typedef unsigned long pgprot_t;
181#define __pgd(x)	(x)
182#define __pgprot(x)	(x)
183
184#endif
185
186struct page;
187extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
188extern void copy_user_page(void *to, void *from, unsigned long vaddr,
189		struct page *p);
190extern int page_is_ram(unsigned long pfn);
191
192struct vm_area_struct;
193extern const char *arch_vma_name(struct vm_area_struct *vma);
194
195#include <asm-generic/memory_model.h>
196#endif /* __ASSEMBLY__ */
197
198#endif /* __KERNEL__ */
199
200#endif /* _ASM_POWERPC_PAGE_H */
201