1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_M32R_PGTABLE_H
3 #define _ASM_M32R_PGTABLE_H
4
5 #include <asm-generic/4level-fixup.h>
6
7 #ifdef __KERNEL__
8 /*
9 * The Linux memory management assumes a three-level page table setup. On
10 * the M32R, we use that, but "fold" the mid level into the top-level page
11 * table, so that we physically have the same two-level page table as the
12 * M32R mmu expects.
13 *
14 * This file contains the functions and defines necessary to modify and use
15 * the M32R page table tree.
16 */
17
18 /* CAUTION!: If you change macro definitions in this file, you might have to
19 * change arch/m32r/mmu.S manually.
20 */
21
22 #ifndef __ASSEMBLY__
23
24 #include <linux/threads.h>
25 #include <linux/bitops.h>
26 #include <asm/processor.h>
27 #include <asm/addrspace.h>
28 #include <asm/page.h>
29
30 struct mm_struct;
31 struct vm_area_struct;
32
33 extern pgd_t swapper_pg_dir[1024];
34 extern void paging_init(void);
35
36 /*
37 * ZERO_PAGE is a global shared page that is always zero: used
38 * for zero-mapped memory areas etc..
39 */
40 extern unsigned long empty_zero_page[1024];
41 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
42
43 #endif /* !__ASSEMBLY__ */
44
45 #ifndef __ASSEMBLY__
46 #include <asm/pgtable-2level.h>
47 #endif
48
49 #define pgtable_cache_init() do { } while (0)
50
51 #define PMD_SIZE (1UL << PMD_SHIFT)
52 #define PMD_MASK (~(PMD_SIZE - 1))
53 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
54 #define PGDIR_MASK (~(PGDIR_SIZE - 1))
55
56 #define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
57 #define FIRST_USER_ADDRESS 0UL
58
59 #ifndef __ASSEMBLY__
60 /* Just any arbitrary offset to the start of the vmalloc VM area: the
61 * current 8MB value just means that there will be a 8MB "hole" after the
62 * physical memory until the kernel virtual memory starts. That means that
63 * any out-of-bounds memory accesses will hopefully be caught.
64 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
65 * area for the same reason. ;)
66 */
67 #define VMALLOC_START KSEG2
68 #define VMALLOC_END KSEG3
69
70 /*
71 * M32R TLB format
72 *
73 * [0] [1:19] [20:23] [24:31]
74 * +-----------------------+----+-------------+
75 * | VPN |0000| ASID |
76 * +-----------------------+----+-------------+
77 * +-+---------------------+----+-+---+-+-+-+-+
78 * |0 PPN |0000|N|AC |L|G|V| |
79 * +-+---------------------+----+-+---+-+-+-+-+
80 * RWX
81 */
82
83 #define _PAGE_BIT_DIRTY 0 /* software: page changed */
84 #define _PAGE_BIT_PRESENT 1 /* Valid: page is valid */
85 #define _PAGE_BIT_GLOBAL 2 /* Global */
86 #define _PAGE_BIT_LARGE 3 /* Large */
87 #define _PAGE_BIT_EXEC 4 /* Execute */
88 #define _PAGE_BIT_WRITE 5 /* Write */
89 #define _PAGE_BIT_READ 6 /* Read */
90 #define _PAGE_BIT_NONCACHABLE 7 /* Non cachable */
91 #define _PAGE_BIT_ACCESSED 8 /* software: page referenced */
92 #define _PAGE_BIT_PROTNONE 9 /* software: if not present */
93
94 #define _PAGE_DIRTY (1UL << _PAGE_BIT_DIRTY)
95 #define _PAGE_PRESENT (1UL << _PAGE_BIT_PRESENT)
96 #define _PAGE_GLOBAL (1UL << _PAGE_BIT_GLOBAL)
97 #define _PAGE_LARGE (1UL << _PAGE_BIT_LARGE)
98 #define _PAGE_EXEC (1UL << _PAGE_BIT_EXEC)
99 #define _PAGE_WRITE (1UL << _PAGE_BIT_WRITE)
100 #define _PAGE_READ (1UL << _PAGE_BIT_READ)
101 #define _PAGE_NONCACHABLE (1UL << _PAGE_BIT_NONCACHABLE)
102 #define _PAGE_ACCESSED (1UL << _PAGE_BIT_ACCESSED)
103 #define _PAGE_PROTNONE (1UL << _PAGE_BIT_PROTNONE)
104
105 #define _PAGE_TABLE \
106 ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
107 | _PAGE_DIRTY )
108 #define _KERNPG_TABLE \
109 ( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
110 | _PAGE_DIRTY )
111 #define _PAGE_CHG_MASK \
112 ( PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY )
113
114 #ifdef CONFIG_MMU
115 #define PAGE_NONE \
116 __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
117 #define PAGE_SHARED \
118 __pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED)
119 #define PAGE_SHARED_EXEC \
120 __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ \
121 | _PAGE_ACCESSED)
122 #define PAGE_COPY \
123 __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
124 #define PAGE_COPY_EXEC \
125 __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
126 #define PAGE_READONLY \
127 __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
128 #define PAGE_READONLY_EXEC \
129 __pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
130
131 #define __PAGE_KERNEL \
132 ( _PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ | _PAGE_DIRTY \
133 | _PAGE_ACCESSED )
134 #define __PAGE_KERNEL_RO ( __PAGE_KERNEL & ~_PAGE_WRITE )
135 #define __PAGE_KERNEL_NOCACHE ( __PAGE_KERNEL | _PAGE_NONCACHABLE)
136
137 #define MAKE_GLOBAL(x) __pgprot((x) | _PAGE_GLOBAL)
138
139 #define PAGE_KERNEL MAKE_GLOBAL(__PAGE_KERNEL)
140 #define PAGE_KERNEL_RO MAKE_GLOBAL(__PAGE_KERNEL_RO)
141 #define PAGE_KERNEL_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
142
143 #else
144 #define PAGE_NONE __pgprot(0)
145 #define PAGE_SHARED __pgprot(0)
146 #define PAGE_SHARED_EXEC __pgprot(0)
147 #define PAGE_COPY __pgprot(0)
148 #define PAGE_COPY_EXEC __pgprot(0)
149 #define PAGE_READONLY __pgprot(0)
150 #define PAGE_READONLY_EXEC __pgprot(0)
151
152 #define PAGE_KERNEL __pgprot(0)
153 #define PAGE_KERNEL_RO __pgprot(0)
154 #define PAGE_KERNEL_NOCACHE __pgprot(0)
155 #endif /* CONFIG_MMU */
156
157 /* xwr */
158 #define __P000 PAGE_NONE
159 #define __P001 PAGE_READONLY
160 #define __P010 PAGE_COPY
161 #define __P011 PAGE_COPY
162 #define __P100 PAGE_READONLY_EXEC
163 #define __P101 PAGE_READONLY_EXEC
164 #define __P110 PAGE_COPY_EXEC
165 #define __P111 PAGE_COPY_EXEC
166
167 #define __S000 PAGE_NONE
168 #define __S001 PAGE_READONLY
169 #define __S010 PAGE_SHARED
170 #define __S011 PAGE_SHARED
171 #define __S100 PAGE_READONLY_EXEC
172 #define __S101 PAGE_READONLY_EXEC
173 #define __S110 PAGE_SHARED_EXEC
174 #define __S111 PAGE_SHARED_EXEC
175
176 /* page table for 0-4MB for everybody */
177
178 #define pte_present(x) (pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
179 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
180
181 #define pmd_none(x) (!pmd_val(x))
182 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
183 #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
184 #define pmd_bad(x) ((pmd_val(x) & ~PAGE_MASK) != _KERNPG_TABLE)
185
186 #define pages_to_mb(x) ((x) >> (20 - PAGE_SHIFT))
187
188 /*
189 * The following only work if pte_present() is true.
190 * Undefined behaviour if not..
191 */
pte_dirty(pte_t pte)192 static inline int pte_dirty(pte_t pte)
193 {
194 return pte_val(pte) & _PAGE_DIRTY;
195 }
196
pte_young(pte_t pte)197 static inline int pte_young(pte_t pte)
198 {
199 return pte_val(pte) & _PAGE_ACCESSED;
200 }
201
pte_write(pte_t pte)202 static inline int pte_write(pte_t pte)
203 {
204 return pte_val(pte) & _PAGE_WRITE;
205 }
206
pte_special(pte_t pte)207 static inline int pte_special(pte_t pte)
208 {
209 return 0;
210 }
211
pte_mkclean(pte_t pte)212 static inline pte_t pte_mkclean(pte_t pte)
213 {
214 pte_val(pte) &= ~_PAGE_DIRTY;
215 return pte;
216 }
217
pte_mkold(pte_t pte)218 static inline pte_t pte_mkold(pte_t pte)
219 {
220 pte_val(pte) &= ~_PAGE_ACCESSED;
221 return pte;
222 }
223
pte_wrprotect(pte_t pte)224 static inline pte_t pte_wrprotect(pte_t pte)
225 {
226 pte_val(pte) &= ~_PAGE_WRITE;
227 return pte;
228 }
229
pte_mkdirty(pte_t pte)230 static inline pte_t pte_mkdirty(pte_t pte)
231 {
232 pte_val(pte) |= _PAGE_DIRTY;
233 return pte;
234 }
235
pte_mkyoung(pte_t pte)236 static inline pte_t pte_mkyoung(pte_t pte)
237 {
238 pte_val(pte) |= _PAGE_ACCESSED;
239 return pte;
240 }
241
pte_mkwrite(pte_t pte)242 static inline pte_t pte_mkwrite(pte_t pte)
243 {
244 pte_val(pte) |= _PAGE_WRITE;
245 return pte;
246 }
247
pte_mkspecial(pte_t pte)248 static inline pte_t pte_mkspecial(pte_t pte)
249 {
250 return pte;
251 }
252
ptep_test_and_clear_young(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep)253 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
254 {
255 return test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep);
256 }
257
ptep_set_wrprotect(struct mm_struct * mm,unsigned long addr,pte_t * ptep)258 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
259 {
260 clear_bit(_PAGE_BIT_WRITE, ptep);
261 }
262
263 /*
264 * Macro and implementation to make a page protection as uncachable.
265 */
pgprot_noncached(pgprot_t _prot)266 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
267 {
268 unsigned long prot = pgprot_val(_prot);
269
270 prot |= _PAGE_NONCACHABLE;
271 return __pgprot(prot);
272 }
273
274 #define pgprot_writecombine(prot) pgprot_noncached(prot)
275
276 /*
277 * Conversion functions: convert a page and protection to a page entry,
278 * and a page entry and page directory to the page they refer to.
279 */
280 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), pgprot)
281
pte_modify(pte_t pte,pgprot_t newprot)282 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
283 {
284 set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) \
285 | pgprot_val(newprot)));
286
287 return pte;
288 }
289
290 /*
291 * Conversion functions: convert a page and protection to a page entry,
292 * and a page entry and page directory to the page they refer to.
293 */
294
pmd_set(pmd_t * pmdp,pte_t * ptep)295 static inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
296 {
297 pmd_val(*pmdp) = (((unsigned long) ptep) & PAGE_MASK);
298 }
299
300 #define pmd_page_vaddr(pmd) \
301 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
302
303 #ifndef CONFIG_DISCONTIGMEM
304 #define pmd_page(pmd) (mem_map + ((pmd_val(pmd) >> PAGE_SHIFT) - PFN_BASE))
305 #endif /* !CONFIG_DISCONTIGMEM */
306
307 /* to find an entry in a page-table-directory. */
308 #define pgd_index(address) \
309 (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
310
311 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
312
313 /* to find an entry in a kernel page-table-directory */
314 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
315
316 #define pmd_index(address) \
317 (((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
318
319 #define pte_index(address) \
320 (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
321 #define pte_offset_kernel(dir, address) \
322 ((pte_t *)pmd_page_vaddr(*(dir)) + pte_index(address))
323 #define pte_offset_map(dir, address) \
324 ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
325 #define pte_unmap(pte) do { } while (0)
326
327 /* Encode and de-code a swap entry */
328 #define __swp_type(x) (((x).val >> 2) & 0x1f)
329 #define __swp_offset(x) ((x).val >> 10)
330 #define __swp_entry(type, offset) \
331 ((swp_entry_t) { ((type) << 2) | ((offset) << 10) })
332 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
333 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
334
335 #endif /* !__ASSEMBLY__ */
336
337 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
338 #define kern_addr_valid(addr) (1)
339
340 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
341 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
342 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
343 #define __HAVE_ARCH_PTE_SAME
344 #include <asm-generic/pgtable.h>
345
346 #endif /* __KERNEL__ */
347
348 #endif /* _ASM_M32R_PGTABLE_H */
349