1 /* Included from asm/pgtable-*.h only ! */
2 
3 /*
4  * Some bits are only used on some cpu families... Make sure that all
5  * the undefined gets a sensible default
6  */
7 #ifndef _PAGE_HASHPTE
8 #define _PAGE_HASHPTE	0
9 #endif
10 #ifndef _PAGE_SHARED
11 #define _PAGE_SHARED	0
12 #endif
13 #ifndef _PAGE_HWWRITE
14 #define _PAGE_HWWRITE	0
15 #endif
16 #ifndef _PAGE_EXEC
17 #define _PAGE_EXEC	0
18 #endif
19 #ifndef _PAGE_ENDIAN
20 #define _PAGE_ENDIAN	0
21 #endif
22 #ifndef _PAGE_COHERENT
23 #define _PAGE_COHERENT	0
24 #endif
25 #ifndef _PAGE_WRITETHRU
26 #define _PAGE_WRITETHRU	0
27 #endif
28 #ifndef _PAGE_4K_PFN
29 #define _PAGE_4K_PFN		0
30 #endif
31 #ifndef _PAGE_SAO
32 #define _PAGE_SAO	0
33 #endif
34 #ifndef _PAGE_PSIZE
35 #define _PAGE_PSIZE		0
36 #endif
37 /* _PAGE_RO and _PAGE_RW shall not be defined at the same time */
38 #ifndef _PAGE_RO
39 #define _PAGE_RO 0
40 #else
41 #define _PAGE_RW 0
42 #endif
43 #ifndef _PMD_PRESENT_MASK
44 #define _PMD_PRESENT_MASK	_PMD_PRESENT
45 #endif
46 #ifndef _PMD_SIZE
47 #define _PMD_SIZE	0
48 #define PMD_PAGE_SIZE(pmd)	bad_call_to_PMD_PAGE_SIZE()
49 #endif
50 #ifndef _PAGE_KERNEL_RO
51 #define _PAGE_KERNEL_RO		(_PAGE_RO)
52 #endif
53 #ifndef _PAGE_KERNEL_ROX
54 #define _PAGE_KERNEL_ROX	(_PAGE_EXEC | _PAGE_RO)
55 #endif
56 #ifndef _PAGE_KERNEL_RW
57 #define _PAGE_KERNEL_RW		(_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE)
58 #endif
59 #ifndef _PAGE_KERNEL_RWX
60 #define _PAGE_KERNEL_RWX	(_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE | _PAGE_EXEC)
61 #endif
62 #ifndef _PAGE_HPTEFLAGS
63 #define _PAGE_HPTEFLAGS _PAGE_HASHPTE
64 #endif
65 #ifndef _PTE_NONE_MASK
66 #define _PTE_NONE_MASK	_PAGE_HPTEFLAGS
67 #endif
68 
69 /* Make sure we get a link error if PMD_PAGE_SIZE is ever called on a
70  * kernel without large page PMD support
71  */
72 #ifndef __ASSEMBLY__
73 extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
74 #endif /* __ASSEMBLY__ */
75 
76 /* Location of the PFN in the PTE. Most 32-bit platforms use the same
77  * as _PAGE_SHIFT here (ie, naturally aligned).
78  * Platform who don't just pre-define the value so we don't override it here
79  */
80 #ifndef PTE_RPN_SHIFT
81 #define PTE_RPN_SHIFT	(PAGE_SHIFT)
82 #endif
83 
84 /* The mask convered by the RPN must be a ULL on 32-bit platforms with
85  * 64-bit PTEs
86  */
87 #if defined(CONFIG_PPC32) && defined(CONFIG_PTE_64BIT)
88 #define PTE_RPN_MAX	(1ULL << (64 - PTE_RPN_SHIFT))
89 #define PTE_RPN_MASK	(~((1ULL<<PTE_RPN_SHIFT)-1))
90 #else
91 #define PTE_RPN_MAX	(1UL << (32 - PTE_RPN_SHIFT))
92 #define PTE_RPN_MASK	(~((1UL<<PTE_RPN_SHIFT)-1))
93 #endif
94 
95 /* _PAGE_CHG_MASK masks of bits that are to be preserved across
96  * pgprot changes
97  */
98 #define _PAGE_CHG_MASK	(PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \
99                          _PAGE_ACCESSED | _PAGE_SPECIAL)
100 
101 /* Mask of bits returned by pte_pgprot() */
102 #define PAGE_PROT_BITS	(_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \
103 			 _PAGE_WRITETHRU | _PAGE_ENDIAN | _PAGE_4K_PFN | \
104 			 _PAGE_USER | _PAGE_ACCESSED | _PAGE_RO | \
105 			 _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | _PAGE_EXEC)
106 
107 /*
108  * We define 2 sets of base prot bits, one for basic pages (ie,
109  * cacheable kernel and user pages) and one for non cacheable
110  * pages. We always set _PAGE_COHERENT when SMP is enabled or
111  * the processor might need it for DMA coherency.
112  */
113 #define _PAGE_BASE_NC	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_PSIZE)
114 #if defined(CONFIG_SMP) || defined(CONFIG_PPC_STD_MMU)
115 #define _PAGE_BASE	(_PAGE_BASE_NC | _PAGE_COHERENT)
116 #else
117 #define _PAGE_BASE	(_PAGE_BASE_NC)
118 #endif
119 
120 /* Permission masks used to generate the __P and __S table,
121  *
122  * Note:__pgprot is defined in arch/powerpc/include/asm/page.h
123  *
124  * Write permissions imply read permissions for now (we could make write-only
125  * pages on BookE but we don't bother for now). Execute permission control is
126  * possible on platforms that define _PAGE_EXEC
127  *
128  * Note due to the way vm flags are laid out, the bits are XWR
129  */
130 #define PAGE_NONE	__pgprot(_PAGE_BASE)
131 #define PAGE_SHARED	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
132 #define PAGE_SHARED_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | \
133 				 _PAGE_EXEC)
134 #define PAGE_COPY	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO)
135 #define PAGE_COPY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO | \
136 				 _PAGE_EXEC)
137 #define PAGE_READONLY	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO)
138 #define PAGE_READONLY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RO | \
139 				 _PAGE_EXEC)
140 
141 #define __P000	PAGE_NONE
142 #define __P001	PAGE_READONLY
143 #define __P010	PAGE_COPY
144 #define __P011	PAGE_COPY
145 #define __P100	PAGE_READONLY_X
146 #define __P101	PAGE_READONLY_X
147 #define __P110	PAGE_COPY_X
148 #define __P111	PAGE_COPY_X
149 
150 #define __S000	PAGE_NONE
151 #define __S001	PAGE_READONLY
152 #define __S010	PAGE_SHARED
153 #define __S011	PAGE_SHARED
154 #define __S100	PAGE_READONLY_X
155 #define __S101	PAGE_READONLY_X
156 #define __S110	PAGE_SHARED_X
157 #define __S111	PAGE_SHARED_X
158 
159 /* Permission masks used for kernel mappings */
160 #define PAGE_KERNEL	__pgprot(_PAGE_BASE | _PAGE_KERNEL_RW)
161 #define PAGE_KERNEL_NC	__pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
162 				 _PAGE_NO_CACHE)
163 #define PAGE_KERNEL_NCG	__pgprot(_PAGE_BASE_NC | _PAGE_KERNEL_RW | \
164 				 _PAGE_NO_CACHE | _PAGE_GUARDED)
165 #define PAGE_KERNEL_X	__pgprot(_PAGE_BASE | _PAGE_KERNEL_RWX)
166 #define PAGE_KERNEL_RO	__pgprot(_PAGE_BASE | _PAGE_KERNEL_RO)
167 #define PAGE_KERNEL_ROX	__pgprot(_PAGE_BASE | _PAGE_KERNEL_ROX)
168 
169 /* Protection used for kernel text. We want the debuggers to be able to
170  * set breakpoints anywhere, so don't write protect the kernel text
171  * on platforms where such control is possible.
172  */
173 #if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH) ||\
174 	defined(CONFIG_KPROBES) || defined(CONFIG_DYNAMIC_FTRACE)
175 #define PAGE_KERNEL_TEXT	PAGE_KERNEL_X
176 #else
177 #define PAGE_KERNEL_TEXT	PAGE_KERNEL_ROX
178 #endif
179 
180 /* Make modules code happy. We don't set RO yet */
181 #define PAGE_KERNEL_EXEC	PAGE_KERNEL_X
182 
183 /*
184  * Don't just check for any non zero bits in __PAGE_USER, since for book3e
185  * and PTE_64BIT, PAGE_KERNEL_X contains _PAGE_BAP_SR which is also in
186  * _PAGE_USER.  Need to explicitly match _PAGE_BAP_UR bit in that case too.
187  */
188 #define pte_user(val)		((val & _PAGE_USER) == _PAGE_USER)
189 
190 /* Advertise special mapping type for AGP */
191 #define PAGE_AGP		(PAGE_KERNEL_NC)
192 #define HAVE_PAGE_AGP
193 
194 /* Advertise support for _PAGE_SPECIAL */
195 #define __HAVE_ARCH_PTE_SPECIAL
196 
197