xref: /openbmc/linux/arch/ia64/include/asm/page.h (revision 92a76f6d)
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 # define __pfn_to_phys(pfn)	PFN_PHYS(pfn)
109 #else
110 # include <asm-generic/memory_model.h>
111 #endif
112 #else
113 # include <asm-generic/memory_model.h>
114 #endif
115 
116 #ifdef CONFIG_FLATMEM
117 # define pfn_valid(pfn)		(((pfn) < max_mapnr) && ia64_pfn_valid(pfn))
118 #elif defined(CONFIG_DISCONTIGMEM)
119 extern unsigned long min_low_pfn;
120 extern unsigned long max_low_pfn;
121 # define pfn_valid(pfn)		(((pfn) >= min_low_pfn) && ((pfn) < max_low_pfn) && ia64_pfn_valid(pfn))
122 #endif
123 
124 #define page_to_phys(page)	(page_to_pfn(page) << PAGE_SHIFT)
125 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
126 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
127 
128 typedef union ia64_va {
129 	struct {
130 		unsigned long off : 61;		/* intra-region offset */
131 		unsigned long reg :  3;		/* region number */
132 	} f;
133 	unsigned long l;
134 	void *p;
135 } ia64_va;
136 
137 /*
138  * Note: These macros depend on the fact that PAGE_OFFSET has all
139  * region bits set to 1 and all other bits set to zero.  They are
140  * expressed in this way to ensure they result in a single "dep"
141  * instruction.
142  */
143 #define __pa(x)		({ia64_va _v; _v.l = (long) (x); _v.f.reg = 0; _v.l;})
144 #define __va(x)		({ia64_va _v; _v.l = (long) (x); _v.f.reg = -1; _v.p;})
145 
146 #define REGION_NUMBER(x)	({ia64_va _v; _v.l = (long) (x); _v.f.reg;})
147 #define REGION_OFFSET(x)	({ia64_va _v; _v.l = (long) (x); _v.f.off;})
148 
149 #ifdef CONFIG_HUGETLB_PAGE
150 # define htlbpage_to_page(x)	(((unsigned long) REGION_NUMBER(x) << 61)			\
151 				 | (REGION_OFFSET(x) >> (HPAGE_SHIFT-PAGE_SHIFT)))
152 # define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
153 extern unsigned int hpage_shift;
154 #endif
155 
156 static __inline__ int
157 get_order (unsigned long size)
158 {
159 	long double d = size - 1;
160 	long order;
161 
162 	order = ia64_getf_exp(d);
163 	order = order - PAGE_SHIFT - 0xffff + 1;
164 	if (order < 0)
165 		order = 0;
166 	return order;
167 }
168 
169 #endif /* !__ASSEMBLY__ */
170 
171 #ifdef STRICT_MM_TYPECHECKS
172   /*
173    * These are used to make use of C type-checking..
174    */
175   typedef struct { unsigned long pte; } pte_t;
176   typedef struct { unsigned long pmd; } pmd_t;
177 #if CONFIG_PGTABLE_LEVELS == 4
178   typedef struct { unsigned long pud; } pud_t;
179 #endif
180   typedef struct { unsigned long pgd; } pgd_t;
181   typedef struct { unsigned long pgprot; } pgprot_t;
182   typedef struct page *pgtable_t;
183 
184 # define pte_val(x)	((x).pte)
185 # define pmd_val(x)	((x).pmd)
186 #if CONFIG_PGTABLE_LEVELS == 4
187 # define pud_val(x)	((x).pud)
188 #endif
189 # define pgd_val(x)	((x).pgd)
190 # define pgprot_val(x)	((x).pgprot)
191 
192 # define __pte(x)	((pte_t) { (x) } )
193 # define __pmd(x)	((pmd_t) { (x) } )
194 # define __pgprot(x)	((pgprot_t) { (x) } )
195 
196 #else /* !STRICT_MM_TYPECHECKS */
197   /*
198    * .. while these make it easier on the compiler
199    */
200 # ifndef __ASSEMBLY__
201     typedef unsigned long pte_t;
202     typedef unsigned long pmd_t;
203     typedef unsigned long pgd_t;
204     typedef unsigned long pgprot_t;
205     typedef struct page *pgtable_t;
206 # endif
207 
208 # define pte_val(x)	(x)
209 # define pmd_val(x)	(x)
210 # define pgd_val(x)	(x)
211 # define pgprot_val(x)	(x)
212 
213 # define __pte(x)	(x)
214 # define __pgd(x)	(x)
215 # define __pgprot(x)	(x)
216 #endif /* !STRICT_MM_TYPECHECKS */
217 
218 #define PAGE_OFFSET			RGN_BASE(RGN_KERNEL)
219 
220 #define VM_DATA_DEFAULT_FLAGS		(VM_READ | VM_WRITE |					\
221 					 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC |		\
222 					 (((current->personality & READ_IMPLIES_EXEC) != 0)	\
223 					  ? VM_EXEC : 0))
224 
225 #define GATE_ADDR		RGN_BASE(RGN_GATE)
226 
227 /*
228  * 0xa000000000000000+2*PERCPU_PAGE_SIZE
229  * - 0xa000000000000000+3*PERCPU_PAGE_SIZE remain unmapped (guard page)
230  */
231 #define KERNEL_START		 (GATE_ADDR+__IA64_UL_CONST(0x100000000))
232 #define PERCPU_ADDR		(-PERCPU_PAGE_SIZE)
233 #define LOAD_OFFSET		(KERNEL_START - KERNEL_TR_PAGE_SIZE)
234 
235 #define __HAVE_ARCH_GATE_AREA	1
236 
237 #endif /* _ASM_IA64_PAGE_H */
238