xref: /openbmc/linux/arch/ia64/include/asm/page.h (revision ee89bd6b)
1 #ifndef _ASM_IA64_PAGE_H
2 #define _ASM_IA64_PAGE_H
3 /*
4  * Pagetable related stuff.
5  *
6  * Copyright (C) 1998, 1999, 2002 Hewlett-Packard Co
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  */
9 
10 #include <asm/intrinsics.h>
11 #include <asm/types.h>
12 
13 /*
14  * The top three bits of an IA64 address are its Region Number.
15  * Different regions are assigned to different purposes.
16  */
17 #define RGN_SHIFT	(61)
18 #define RGN_BASE(r)	(__IA64_UL_CONST(r)<<RGN_SHIFT)
19 #define RGN_BITS	(RGN_BASE(-1))
20 
21 #define RGN_KERNEL	7	/* Identity mapped region */
22 #define RGN_UNCACHED    6	/* Identity mapped I/O region */
23 #define RGN_GATE	5	/* Gate page, Kernel text, etc */
24 #define RGN_HPAGE	4	/* For Huge TLB pages */
25 
26 /*
27  * PAGE_SHIFT determines the actual kernel page size.
28  */
29 #if defined(CONFIG_IA64_PAGE_SIZE_4KB)
30 # define PAGE_SHIFT	12
31 #elif defined(CONFIG_IA64_PAGE_SIZE_8KB)
32 # define PAGE_SHIFT	13
33 #elif defined(CONFIG_IA64_PAGE_SIZE_16KB)
34 # define PAGE_SHIFT	14
35 #elif defined(CONFIG_IA64_PAGE_SIZE_64KB)
36 # define PAGE_SHIFT	16
37 #else
38 # error Unsupported page size!
39 #endif
40 
41 #define PAGE_SIZE		(__IA64_UL_CONST(1) << PAGE_SHIFT)
42 #define PAGE_MASK		(~(PAGE_SIZE - 1))
43 
44 #define PERCPU_PAGE_SHIFT	18	/* log2() of max. size of per-CPU area */
45 #define PERCPU_PAGE_SIZE	(__IA64_UL_CONST(1) << PERCPU_PAGE_SHIFT)
46 
47 
48 #ifdef CONFIG_HUGETLB_PAGE
49 # define HPAGE_REGION_BASE	RGN_BASE(RGN_HPAGE)
50 # define HPAGE_SHIFT		hpage_shift
51 # define HPAGE_SHIFT_DEFAULT	28	/* check ia64 SDM for architecture supported size */
52 # define HPAGE_SIZE		(__IA64_UL_CONST(1) << HPAGE_SHIFT)
53 # define HPAGE_MASK		(~(HPAGE_SIZE - 1))
54 
55 # define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
56 #endif /* CONFIG_HUGETLB_PAGE */
57 
58 #ifdef __ASSEMBLY__
59 # define __pa(x)		((x) - PAGE_OFFSET)
60 # define __va(x)		((x) + PAGE_OFFSET)
61 #else /* !__ASSEMBLY */
62 #  define STRICT_MM_TYPECHECKS
63 
64 extern void clear_page (void *page);
65 extern void copy_page (void *to, void *from);
66 
67 /*
68  * clear_user_page() and copy_user_page() can't be inline functions because
69  * flush_dcache_page() can't be defined until later...
70  */
71 #define clear_user_page(addr, vaddr, page)	\
72 do {						\
73 	clear_page(addr);			\
74 	flush_dcache_page(page);		\
75 } while (0)
76 
77 #define copy_user_page(to, from, vaddr, page)	\
78 do {						\
79 	copy_page((to), (from));		\
80 	flush_dcache_page(page);		\
81 } while (0)
82 
83 
84 #define __alloc_zeroed_user_highpage(movableflags, vma, vaddr)		\
85 ({									\
86 	struct page *page = alloc_page_vma(				\
87 		GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr);	\
88 	if (page)							\
89  		flush_dcache_page(page);				\
90 	page;								\
91 })
92 
93 #define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
94 
95 #define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
96 
97 #ifdef CONFIG_VIRTUAL_MEM_MAP
98 extern int ia64_pfn_valid (unsigned long pfn);
99 #else
100 # define ia64_pfn_valid(pfn) 1
101 #endif
102 
103 #ifdef CONFIG_VIRTUAL_MEM_MAP
104 extern struct page *vmem_map;
105 #ifdef CONFIG_DISCONTIGMEM
106 # define page_to_pfn(page)	((unsigned long) (page - vmem_map))
107 # define pfn_to_page(pfn)	(vmem_map + (pfn))
108 #else
109 # include <asm-generic/memory_model.h>
110 #endif
111 #else
112 # include <asm-generic/memory_model.h>
113 #endif
114 
115 #ifdef CONFIG_FLATMEM
116 # define pfn_valid(pfn)		(((pfn) < max_mapnr) && ia64_pfn_valid(pfn))
117 #elif defined(CONFIG_DISCONTIGMEM)
118 extern unsigned long min_low_pfn;
119 extern unsigned long max_low_pfn;
120 # define pfn_valid(pfn)		(((pfn) >= min_low_pfn) && ((pfn) < max_low_pfn) && ia64_pfn_valid(pfn))
121 #endif
122 
123 #define page_to_phys(page)	(page_to_pfn(page) << PAGE_SHIFT)
124 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
125 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
126 
127 typedef union ia64_va {
128 	struct {
129 		unsigned long off : 61;		/* intra-region offset */
130 		unsigned long reg :  3;		/* region number */
131 	} f;
132 	unsigned long l;
133 	void *p;
134 } ia64_va;
135 
136 /*
137  * Note: These macros depend on the fact that PAGE_OFFSET has all
138  * region bits set to 1 and all other bits set to zero.  They are
139  * expressed in this way to ensure they result in a single "dep"
140  * instruction.
141  */
142 #define __pa(x)		({ia64_va _v; _v.l = (long) (x); _v.f.reg = 0; _v.l;})
143 #define __va(x)		({ia64_va _v; _v.l = (long) (x); _v.f.reg = -1; _v.p;})
144 
145 #define REGION_NUMBER(x)	({ia64_va _v; _v.l = (long) (x); _v.f.reg;})
146 #define REGION_OFFSET(x)	({ia64_va _v; _v.l = (long) (x); _v.f.off;})
147 
148 #ifdef CONFIG_HUGETLB_PAGE
149 # define htlbpage_to_page(x)	(((unsigned long) REGION_NUMBER(x) << 61)			\
150 				 | (REGION_OFFSET(x) >> (HPAGE_SHIFT-PAGE_SHIFT)))
151 # define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
152 extern unsigned int hpage_shift;
153 #endif
154 
155 static __inline__ int
156 get_order (unsigned long size)
157 {
158 	long double d = size - 1;
159 	long order;
160 
161 	order = ia64_getf_exp(d);
162 	order = order - PAGE_SHIFT - 0xffff + 1;
163 	if (order < 0)
164 		order = 0;
165 	return order;
166 }
167 
168 #endif /* !__ASSEMBLY__ */
169 
170 #ifdef STRICT_MM_TYPECHECKS
171   /*
172    * These are used to make use of C type-checking..
173    */
174   typedef struct { unsigned long pte; } pte_t;
175   typedef struct { unsigned long pmd; } pmd_t;
176 #ifdef CONFIG_PGTABLE_4
177   typedef struct { unsigned long pud; } pud_t;
178 #endif
179   typedef struct { unsigned long pgd; } pgd_t;
180   typedef struct { unsigned long pgprot; } pgprot_t;
181   typedef struct page *pgtable_t;
182 
183 # define pte_val(x)	((x).pte)
184 # define pmd_val(x)	((x).pmd)
185 #ifdef CONFIG_PGTABLE_4
186 # define pud_val(x)	((x).pud)
187 #endif
188 # define pgd_val(x)	((x).pgd)
189 # define pgprot_val(x)	((x).pgprot)
190 
191 # define __pte(x)	((pte_t) { (x) } )
192 # define __pmd(x)	((pmd_t) { (x) } )
193 # define __pgprot(x)	((pgprot_t) { (x) } )
194 
195 #else /* !STRICT_MM_TYPECHECKS */
196   /*
197    * .. while these make it easier on the compiler
198    */
199 # ifndef __ASSEMBLY__
200     typedef unsigned long pte_t;
201     typedef unsigned long pmd_t;
202     typedef unsigned long pgd_t;
203     typedef unsigned long pgprot_t;
204     typedef struct page *pgtable_t;
205 # endif
206 
207 # define pte_val(x)	(x)
208 # define pmd_val(x)	(x)
209 # define pgd_val(x)	(x)
210 # define pgprot_val(x)	(x)
211 
212 # define __pte(x)	(x)
213 # define __pgd(x)	(x)
214 # define __pgprot(x)	(x)
215 #endif /* !STRICT_MM_TYPECHECKS */
216 
217 #define PAGE_OFFSET			RGN_BASE(RGN_KERNEL)
218 
219 #define VM_DATA_DEFAULT_FLAGS		(VM_READ | VM_WRITE |					\
220 					 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC |		\
221 					 (((current->personality & READ_IMPLIES_EXEC) != 0)	\
222 					  ? VM_EXEC : 0))
223 
224 #define GATE_ADDR		RGN_BASE(RGN_GATE)
225 
226 /*
227  * 0xa000000000000000+2*PERCPU_PAGE_SIZE
228  * - 0xa000000000000000+3*PERCPU_PAGE_SIZE remain unmapped (guard page)
229  */
230 #define KERNEL_START		 (GATE_ADDR+__IA64_UL_CONST(0x100000000))
231 #define PERCPU_ADDR		(-PERCPU_PAGE_SIZE)
232 #define LOAD_OFFSET		(KERNEL_START - KERNEL_TR_PAGE_SIZE)
233 
234 #endif /* _ASM_IA64_PAGE_H */
235