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pgtable.h
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1 /*
2  * Copyright (C) 2012 ARM Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
15  */
16 #ifndef __ASM_PGTABLE_H
17 #define __ASM_PGTABLE_H
18 
19 #include <asm/proc-fns.h>
20 
21 #include <asm/memory.h>
22 #include <asm/pgtable-hwdef.h>
23 
24 /*
25  * Software defined PTE bits definition.
26  */
27 #define PTE_VALID (_AT(pteval_t, 1) << 0) /* pte_present() check */
28 #define PTE_FILE (_AT(pteval_t, 1) << 2) /* only when !pte_present() */
29 #define PTE_DIRTY (_AT(pteval_t, 1) << 55)
30 #define PTE_SPECIAL (_AT(pteval_t, 1) << 56)
31 
32 /*
33  * VMALLOC and SPARSEMEM_VMEMMAP ranges.
34  */
35 #define VMALLOC_START UL(0xffffff8000000000)
36 #define VMALLOC_END (PAGE_OFFSET - UL(0x400000000) - SZ_64K)
37 
38 #define vmemmap ((struct page *)(VMALLOC_END + SZ_64K))
39 
40 #define FIRST_USER_ADDRESS 0
41 
42 #ifndef __ASSEMBLY__
43 extern void __pte_error(const char *file, int line, unsigned long val);
44 extern void __pmd_error(const char *file, int line, unsigned long val);
45 extern void __pgd_error(const char *file, int line, unsigned long val);
46 
47 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte))
48 #ifndef CONFIG_ARM64_64K_PAGES
49 #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
50 #endif
51 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
52 
53 /*
54  * The pgprot_* and protection_map entries will be fixed up at runtime to
55  * include the cachable and bufferable bits based on memory policy, as well as
56  * any architecture dependent bits like global/ASID and SMP shared mapping
57  * bits.
58  */
59 #define _PAGE_DEFAULT PTE_TYPE_PAGE | PTE_AF
60 
61 extern pgprot_t pgprot_default;
62 
63 #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
64 
65 #define PAGE_NONE _MOD_PROT(pgprot_default, PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
66 #define PAGE_SHARED _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
67 #define PAGE_SHARED_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN)
68 #define PAGE_COPY _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
69 #define PAGE_COPY_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_RDONLY)
70 #define PAGE_READONLY _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
71 #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_default, PTE_USER | PTE_NG | PTE_PXN | PTE_RDONLY)
72 #define PAGE_KERNEL _MOD_PROT(pgprot_default, PTE_PXN | PTE_UXN | PTE_DIRTY)
73 #define PAGE_KERNEL_EXEC _MOD_PROT(pgprot_default, PTE_UXN | PTE_DIRTY)
74 
75 #define __PAGE_NONE __pgprot(_PAGE_DEFAULT | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
76 #define __PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
77 #define __PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN)
78 #define __PAGE_COPY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
79 #define __PAGE_COPY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_RDONLY)
80 #define __PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_RDONLY)
81 #define __PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_RDONLY)
82 
83 #endif /* __ASSEMBLY__ */
84 
85 #define __P000 __PAGE_NONE
86 #define __P001 __PAGE_READONLY
87 #define __P010 __PAGE_COPY
88 #define __P011 __PAGE_COPY
89 #define __P100 __PAGE_READONLY_EXEC
90 #define __P101 __PAGE_READONLY_EXEC
91 #define __P110 __PAGE_COPY_EXEC
92 #define __P111 __PAGE_COPY_EXEC
93 
94 #define __S000 __PAGE_NONE
95 #define __S001 __PAGE_READONLY
96 #define __S010 __PAGE_SHARED
97 #define __S011 __PAGE_SHARED
98 #define __S100 __PAGE_READONLY_EXEC
99 #define __S101 __PAGE_READONLY_EXEC
100 #define __S110 __PAGE_SHARED_EXEC
101 #define __S111 __PAGE_SHARED_EXEC
102 
103 #ifndef __ASSEMBLY__
104 /*
105  * ZERO_PAGE is a global shared page that is always zero: used
106  * for zero-mapped memory areas etc..
107  */
108 extern struct page *empty_zero_page;
109 #define ZERO_PAGE(vaddr) (empty_zero_page)
110 
111 #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT)
112 
113 #define pfn_pte(pfn,prot) (__pte(((phys_addr_t)(pfn) << PAGE_SHIFT) | pgprot_val(prot)))
114 
115 #define pte_none(pte) (!pte_val(pte))
116 #define pte_clear(mm,addr,ptep) set_pte(ptep, __pte(0))
117 #define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
118 #define pte_offset_kernel(dir,addr) (pmd_page_vaddr(*(dir)) + __pte_index(addr))
119 
120 #define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr))
121 #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
122 #define pte_unmap(pte) do { } while (0)
123 #define pte_unmap_nested(pte) do { } while (0)
124 
125 /*
126  * The following only work if pte_present(). Undefined behaviour otherwise.
127  */
128 #define pte_present(pte) (pte_val(pte) & PTE_VALID)
129 #define pte_dirty(pte) (pte_val(pte) & PTE_DIRTY)
130 #define pte_young(pte) (pte_val(pte) & PTE_AF)
131 #define pte_special(pte) (pte_val(pte) & PTE_SPECIAL)
132 #define pte_write(pte) (!(pte_val(pte) & PTE_RDONLY))
133 #define pte_exec(pte) (!(pte_val(pte) & PTE_UXN))
134 
135 #define pte_present_exec_user(pte) \
136  ((pte_val(pte) & (PTE_VALID | PTE_USER | PTE_UXN)) == \
137  (PTE_VALID | PTE_USER))
138 
139 #define PTE_BIT_FUNC(fn,op) \
140 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
141 
142 PTE_BIT_FUNC(wrprotect, |= PTE_RDONLY);
143 PTE_BIT_FUNC(mkwrite, &= ~PTE_RDONLY);
144 PTE_BIT_FUNC(mkclean, &= ~PTE_DIRTY);
145 PTE_BIT_FUNC(mkdirty, |= PTE_DIRTY);
146 PTE_BIT_FUNC(mkold, &= ~PTE_AF);
147 PTE_BIT_FUNC(mkyoung, |= PTE_AF);
148 PTE_BIT_FUNC(mkspecial, |= PTE_SPECIAL);
149 
150 static inline void set_pte(pte_t *ptep, pte_t pte)
151 {
152  *ptep = pte;
153 }
154 
155 extern void __sync_icache_dcache(pte_t pteval, unsigned long addr);
156 
157 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
158  pte_t *ptep, pte_t pte)
159 {
160  if (pte_present_exec_user(pte))
161  __sync_icache_dcache(pte, addr);
162  set_pte(ptep, pte);
163 }
164 
165 /*
166  * Huge pte definitions.
167  */
168 #define pte_huge(pte) ((pte_val(pte) & PTE_TYPE_MASK) == PTE_TYPE_HUGEPAGE)
169 #define pte_mkhuge(pte) (__pte((pte_val(pte) & ~PTE_TYPE_MASK) | PTE_TYPE_HUGEPAGE))
170 
171 #define __pgprot_modify(prot,mask,bits) \
172  __pgprot((pgprot_val(prot) & ~(mask)) | (bits))
173 
174 #define __HAVE_ARCH_PTE_SPECIAL
175 
176 /*
177  * Mark the prot value as uncacheable and unbufferable.
178  */
179 #define pgprot_noncached(prot) \
180  __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_nGnRnE))
181 #define pgprot_writecombine(prot) \
182  __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_DEVICE_GRE))
183 #define pgprot_dmacoherent(prot) \
184  __pgprot_modify(prot, PTE_ATTRINDX_MASK, PTE_ATTRINDX(MT_NORMAL_NC))
185 #define __HAVE_PHYS_MEM_ACCESS_PROT
186 struct file;
187 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
188  unsigned long size, pgprot_t vma_prot);
189 
190 #define pmd_none(pmd) (!pmd_val(pmd))
191 #define pmd_present(pmd) (pmd_val(pmd))
192 
193 #define pmd_bad(pmd) (!(pmd_val(pmd) & 2))
194 
195 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
196 {
197  *pmdp = pmd;
198  dsb();
199 }
200 
201 static inline void pmd_clear(pmd_t *pmdp)
202 {
203  set_pmd(pmdp, __pmd(0));
204 }
205 
206 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
207 {
208  return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK);
209 }
210 
211 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK))
212 
213 /*
214  * Conversion functions: convert a page and protection to a page entry,
215  * and a page entry and page directory to the page they refer to.
216  */
217 #define mk_pte(page,prot) pfn_pte(page_to_pfn(page),prot)
218 
219 #ifndef CONFIG_ARM64_64K_PAGES
220 
221 #define pud_none(pud) (!pud_val(pud))
222 #define pud_bad(pud) (!(pud_val(pud) & 2))
223 #define pud_present(pud) (pud_val(pud))
224 
225 static inline void set_pud(pud_t *pudp, pud_t pud)
226 {
227  *pudp = pud;
228  dsb();
229 }
230 
231 static inline void pud_clear(pud_t *pudp)
232 {
233  set_pud(pudp, __pud(0));
234 }
235 
236 static inline pmd_t *pud_page_vaddr(pud_t pud)
237 {
238  return __va(pud_val(pud) & PHYS_MASK & (s32)PAGE_MASK);
239 }
240 
241 #endif /* CONFIG_ARM64_64K_PAGES */
242 
243 /* to find an entry in a page-table-directory */
244 #define pgd_index(addr) (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
245 
246 #define pgd_offset(mm, addr) ((mm)->pgd+pgd_index(addr))
247 
248 /* to find an entry in a kernel page-table-directory */
249 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
250 
251 /* Find an entry in the second-level page table.. */
252 #ifndef CONFIG_ARM64_64K_PAGES
253 #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
254 static inline pmd_t *pmd_offset(pud_t *pud, unsigned long addr)
255 {
256  return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(addr);
257 }
258 #endif
259 
260 /* Find an entry in the third-level page table.. */
261 #define __pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
262 
263 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
264 {
265  const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY;
266  pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
267  return pte;
268 }
269 
270 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
271 extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
272 
273 #define SWAPPER_DIR_SIZE (3 * PAGE_SIZE)
274 #define IDMAP_DIR_SIZE (2 * PAGE_SIZE)
275 
276 /*
277  * Encode and decode a swap entry:
278  * bits 0-1: present (must be zero)
279  * bit 2: PTE_FILE
280  * bits 3-8: swap type
281  * bits 9-63: swap offset
282  */
283 #define __SWP_TYPE_SHIFT 3
284 #define __SWP_TYPE_BITS 6
285 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
286 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
287 
288 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
289 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
290 #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
291 
292 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
293 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
294 
295 /*
296  * Ensure that there are not more swap files than can be encoded in the kernel
297  * the PTEs.
298  */
299 #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
300 
301 /*
302  * Encode and decode a file entry:
303  * bits 0-1: present (must be zero)
304  * bit 2: PTE_FILE
305  * bits 3-63: file offset / PAGE_SIZE
306  */
307 #define pte_file(pte) (pte_val(pte) & PTE_FILE)
308 #define pte_to_pgoff(x) (pte_val(x) >> 3)
309 #define pgoff_to_pte(x) __pte(((x) << 3) | PTE_FILE)
310 
311 #define PTE_FILE_MAX_BITS 61
312 
313 extern int kern_addr_valid(unsigned long addr);
314 
315 #include <asm-generic/pgtable.h>
316 
317 /*
318  * remap a physical page `pfn' of size `size' with page protection `prot'
319  * into virtual address `from'
320  */
321 #define io_remap_pfn_range(vma,from,pfn,size,prot) \
322  remap_pfn_range(vma, from, pfn, size, prot)
323 
324 #define pgtable_cache_init() do { } while (0)
325 
326 #endif /* !__ASSEMBLY__ */
327 
328 #endif /* __ASM_PGTABLE_H */
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