aboutsummaryrefslogtreecommitdiffstats
path: root/include/asm-mn10300/pgtable.h
blob: 6dc30fc827c458d5d2c6e67f964a79b720a96bdc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
/* MN10300 Page table manipulators and constants
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 *
 *
 * The Linux memory management assumes a three-level page table setup. On
 * the i386, we use that, but "fold" the mid level into the top-level page
 * table, so that we physically have the same two-level page table as the
 * i386 mmu expects.
 *
 * This file contains the functions and defines necessary to modify and use
 * the i386 page table tree for the purposes of the MN10300 TLB handler
 * functions.
 */
#ifndef _ASM_PGTABLE_H
#define _ASM_PGTABLE_H

#include <asm/cpu-regs.h>

#ifndef __ASSEMBLY__
#include <asm/processor.h>
#include <asm/cache.h>
#include <linux/threads.h>

#include <asm/bitops.h>

#include <linux/slab.h>
#include <linux/list.h>
#include <linux/spinlock.h>

/*
 * ZERO_PAGE is a global shared page that is always zero: used
 * for zero-mapped memory areas etc..
 */
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
extern unsigned long empty_zero_page[1024];
extern spinlock_t pgd_lock;
extern struct page *pgd_list;

extern void pmd_ctor(void *, struct kmem_cache *, unsigned long);
extern void pgtable_cache_init(void);
extern void paging_init(void);

#endif /* !__ASSEMBLY__ */

/*
 * The Linux mn10300 paging architecture only implements both the traditional
 * 2-level page tables
 */
#define PGDIR_SHIFT	22
#define PTRS_PER_PGD	1024
#define PTRS_PER_PUD	1	/* we don't really have any PUD physically */
#define PTRS_PER_PMD	1	/* we don't really have any PMD physically */
#define PTRS_PER_PTE	1024

#define PGD_SIZE	PAGE_SIZE
#define PMD_SIZE	(1UL << PMD_SHIFT)
#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
#define PGDIR_MASK	(~(PGDIR_SIZE - 1))

#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
#define FIRST_USER_ADDRESS	0

#define USER_PGD_PTRS		(PAGE_OFFSET >> PGDIR_SHIFT)
#define KERNEL_PGD_PTRS		(PTRS_PER_PGD - USER_PGD_PTRS)

#define TWOLEVEL_PGDIR_SHIFT	22
#define BOOT_USER_PGD_PTRS	(__PAGE_OFFSET >> TWOLEVEL_PGDIR_SHIFT)
#define BOOT_KERNEL_PGD_PTRS	(1024 - BOOT_USER_PGD_PTRS)

#ifndef __ASSEMBLY__
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
#endif

/*
 * Unfortunately, due to the way the MMU works on the MN10300, the vmalloc VM
 * area has to be in the lower half of the virtual address range (the upper
 * half is not translated through the TLB).
 *
 * So in this case, the vmalloc area goes at the bottom of the address map
 * (leaving a hole at the very bottom to catch addressing errors), and
 * userspace starts immediately above.
 *
 * The vmalloc() routines also leaves a hole of 4kB between each vmalloced
 * area to catch addressing errors.
 */
#define VMALLOC_OFFSET	(8 * 1024 * 1024)
#define VMALLOC_START	(0x70000000)
#define VMALLOC_END	(0x7C000000)

#ifndef __ASSEMBLY__
extern pte_t kernel_vmalloc_ptes[(VMALLOC_END - VMALLOC_START) / PAGE_SIZE];
#endif

/* IPTEL/DPTEL bit assignments */
#define _PAGE_BIT_VALID		xPTEL_V_BIT
#define _PAGE_BIT_ACCESSED	xPTEL_UNUSED1_BIT	/* mustn't be loaded into IPTEL/DPTEL */
#define _PAGE_BIT_NX		xPTEL_UNUSED2_BIT	/* mustn't be loaded into IPTEL/DPTEL */
#define _PAGE_BIT_CACHE		xPTEL_C_BIT
#define _PAGE_BIT_PRESENT	xPTEL_PV_BIT
#define _PAGE_BIT_DIRTY		xPTEL_D_BIT
#define _PAGE_BIT_GLOBAL	xPTEL_G_BIT

#define _PAGE_VALID		xPTEL_V
#define _PAGE_ACCESSED		xPTEL_UNUSED1
#define _PAGE_NX		xPTEL_UNUSED2		/* no-execute bit */
#define _PAGE_CACHE		xPTEL_C
#define _PAGE_PRESENT		xPTEL_PV
#define _PAGE_DIRTY		xPTEL_D
#define _PAGE_PROT		xPTEL_PR
#define _PAGE_PROT_RKNU		xPTEL_PR_ROK
#define _PAGE_PROT_WKNU		xPTEL_PR_RWK
#define _PAGE_PROT_RKRU		xPTEL_PR_ROK_ROU
#define _PAGE_PROT_WKRU		xPTEL_PR_RWK_ROU
#define _PAGE_PROT_WKWU		xPTEL_PR_RWK_RWU
#define _PAGE_GLOBAL		xPTEL_G
#define _PAGE_PSE		xPTEL_PS_4Mb		/* 4MB page */

#define _PAGE_FILE		xPTEL_UNUSED1_BIT	/* set:pagecache unset:swap */

#define __PAGE_PROT_UWAUX	0x040
#define __PAGE_PROT_USER	0x080
#define __PAGE_PROT_WRITE	0x100

#define _PAGE_PRESENTV		(_PAGE_PRESENT|_PAGE_VALID)
#define _PAGE_PROTNONE		0x000	/* If not present */

#ifndef __ASSEMBLY__

#define VMALLOC_VMADDR(x) ((unsigned long)(x))

#define _PAGE_TABLE	(_PAGE_PRESENTV | _PAGE_PROT_WKNU | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_CHG_MASK	(PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)

#define __PAGE_NONE	(_PAGE_PRESENTV | _PAGE_PROT_RKNU | _PAGE_ACCESSED | _PAGE_CACHE)
#define __PAGE_SHARED	(_PAGE_PRESENTV | _PAGE_PROT_WKWU | _PAGE_ACCESSED | _PAGE_CACHE)
#define __PAGE_COPY	(_PAGE_PRESENTV | _PAGE_PROT_RKRU | _PAGE_ACCESSED | _PAGE_CACHE)
#define __PAGE_READONLY	(_PAGE_PRESENTV | _PAGE_PROT_RKRU | _PAGE_ACCESSED | _PAGE_CACHE)

#define PAGE_NONE		__pgprot(__PAGE_NONE     | _PAGE_NX)
#define PAGE_SHARED_NOEXEC	__pgprot(__PAGE_SHARED   | _PAGE_NX)
#define PAGE_COPY_NOEXEC	__pgprot(__PAGE_COPY     | _PAGE_NX)
#define PAGE_READONLY_NOEXEC	__pgprot(__PAGE_READONLY | _PAGE_NX)
#define PAGE_SHARED_EXEC	__pgprot(__PAGE_SHARED)
#define PAGE_COPY_EXEC		__pgprot(__PAGE_COPY)
#define PAGE_READONLY_EXEC	__pgprot(__PAGE_READONLY)
#define PAGE_COPY		PAGE_COPY_NOEXEC
#define PAGE_READONLY		PAGE_READONLY_NOEXEC
#define PAGE_SHARED		PAGE_SHARED_EXEC

#define __PAGE_KERNEL_BASE (_PAGE_PRESENTV | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_GLOBAL)

#define __PAGE_KERNEL		(__PAGE_KERNEL_BASE | _PAGE_PROT_WKNU | _PAGE_CACHE | _PAGE_NX)
#define __PAGE_KERNEL_NOCACHE	(__PAGE_KERNEL_BASE | _PAGE_PROT_WKNU | _PAGE_NX)
#define __PAGE_KERNEL_EXEC	(__PAGE_KERNEL & ~_PAGE_NX)
#define __PAGE_KERNEL_RO	(__PAGE_KERNEL_BASE | _PAGE_PROT_RKNU | _PAGE_CACHE | _PAGE_NX)
#define __PAGE_KERNEL_LARGE	(__PAGE_KERNEL | _PAGE_PSE)
#define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE)

#define PAGE_KERNEL		__pgprot(__PAGE_KERNEL)
#define PAGE_KERNEL_RO		__pgprot(__PAGE_KERNEL_RO)
#define PAGE_KERNEL_EXEC	__pgprot(__PAGE_KERNEL_EXEC)
#define PAGE_KERNEL_NOCACHE	__pgprot(__PAGE_KERNEL_NOCACHE)
#define PAGE_KERNEL_LARGE	__pgprot(__PAGE_KERNEL_LARGE)
#define PAGE_KERNEL_LARGE_EXEC	__pgprot(__PAGE_KERNEL_LARGE_EXEC)

/*
 * Whilst the MN10300 can do page protection for execute (given separate data
 * and insn TLBs), we are not supporting it at the moment. Write permission,
 * however, always implies read permission (but not execute permission).
 */
#define __P000	PAGE_NONE
#define __P001	PAGE_READONLY_NOEXEC
#define __P010	PAGE_COPY_NOEXEC
#define __P011	PAGE_COPY_NOEXEC
#define __P100	PAGE_READONLY_EXEC
#define __P101	PAGE_READONLY_EXEC
#define __P110	PAGE_COPY_EXEC
#define __P111	PAGE_COPY_EXEC

#define __S000	PAGE_NONE
#define __S001	PAGE_READONLY_NOEXEC
#define __S010	PAGE_SHARED_NOEXEC
#define __S011	PAGE_SHARED_NOEXEC
#define __S100	PAGE_READONLY_EXEC
#define __S101	PAGE_READONLY_EXEC
#define __S110	PAGE_SHARED_EXEC
#define __S111	PAGE_SHARED_EXEC

/*
 * Define this to warn about kernel memory accesses that are
 * done without a 'verify_area(VERIFY_WRITE,..)'
 */
#undef TEST_VERIFY_AREA

#define pte_present(x)	(pte_val(x) & _PAGE_VALID)
#define pte_clear(mm, addr, xp)				\
do {							\
	set_pte_at((mm), (addr), (xp), __pte(0));	\
} while (0)

#define pmd_none(x)	(!pmd_val(x))
#define pmd_present(x)	(!pmd_none(x))
#define pmd_clear(xp)	do { set_pmd(xp, __pmd(0)); } while (0)
#define	pmd_bad(x)	0


#define pages_to_mb(x) ((x) >> (20 - PAGE_SHIFT))

#ifndef __ASSEMBLY__

/*
 * The following only work if pte_present() is true.
 * Undefined behaviour if not..
 */
static inline int pte_user(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_USER; }
static inline int pte_read(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_USER; }
static inline int pte_dirty(pte_t pte)	{ return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte)	{ return pte_val(pte) & _PAGE_ACCESSED; }
static inline int pte_write(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_WRITE; }
static inline int pte_special(pte_t pte){ return 0; }

/*
 * The following only works if pte_present() is not true.
 */
static inline int pte_file(pte_t pte)	{ return pte_val(pte) & _PAGE_FILE; }

static inline pte_t pte_rdprotect(pte_t pte)
{
	pte_val(pte) &= ~(__PAGE_PROT_USER|__PAGE_PROT_UWAUX); return pte;
}
static inline pte_t pte_exprotect(pte_t pte)
{
	pte_val(pte) |= _PAGE_NX; return pte;
}

static inline pte_t pte_wrprotect(pte_t pte)
{
	pte_val(pte) &= ~(__PAGE_PROT_WRITE|__PAGE_PROT_UWAUX); return pte;
}

static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkexec(pte_t pte)	{ pte_val(pte) &= ~_PAGE_NX; return pte; }

static inline pte_t pte_mkread(pte_t pte)
{
	pte_val(pte) |= __PAGE_PROT_USER;
	if (pte_write(pte))
		pte_val(pte) |= __PAGE_PROT_UWAUX;
	return pte;
}
static inline pte_t pte_mkwrite(pte_t pte)
{
	pte_val(pte) |= __PAGE_PROT_WRITE;
	if (pte_val(pte) & __PAGE_PROT_USER)
		pte_val(pte) |= __PAGE_PROT_UWAUX;
	return pte;
}

static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }

#define pte_ERROR(e) \
	printk(KERN_ERR "%s:%d: bad pte %08lx.\n", \
	       __FILE__, __LINE__, pte_val(e))
#define pgd_ERROR(e) \
	printk(KERN_ERR "%s:%d: bad pgd %08lx.\n", \
	       __FILE__, __LINE__, pgd_val(e))

/*
 * The "pgd_xxx()" functions here are trivial for a folded two-level
 * setup: the pgd is never bad, and a pmd always exists (as it's folded
 * into the pgd entry)
 */
#define pgd_clear(xp)				do { } while (0)

/*
 * Certain architectures need to do special things when PTEs
 * within a page table are directly modified.  Thus, the following
 * hook is made available.
 */
#define set_pte(pteptr, pteval)			(*(pteptr) = pteval)
#define set_pte_at(mm, addr, ptep, pteval)	set_pte((ptep), (pteval))
#define set_pte_atomic(pteptr, pteval)		set_pte((pteptr), (pteval))

/*
 * (pmds are folded into pgds so this doesn't get actually called,
 * but the define is needed for a generic inline function.)
 */
#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)

#define ptep_get_and_clear(mm, addr, ptep) \
	__pte(xchg(&(ptep)->pte, 0))
#define pte_same(a, b)		(pte_val(a) == pte_val(b))
#define pte_page(x)		pfn_to_page(pte_pfn(x))
#define pte_none(x)		(!pte_val(x))
#define pte_pfn(x)		((unsigned long) (pte_val(x) >> PAGE_SHIFT))
#define __pfn_addr(pfn)		((pfn) << PAGE_SHIFT)
#define pfn_pte(pfn, prot)	__pte(__pfn_addr(pfn) | pgprot_val(prot))
#define pfn_pmd(pfn, prot)	__pmd(__pfn_addr(pfn) | pgprot_val(prot))

/*
 * All present user pages are user-executable:
 */
static inline int pte_exec(pte_t pte)
{
	return pte_user(pte);
}

/*
 * All present pages are kernel-executable:
 */
static inline int pte_exec_kernel(pte_t pte)
{
	return 1;
}

/*
 * Bits 0 and 1 are taken, split up the 29 bits of offset
 * into this range:
 */
#define PTE_FILE_MAX_BITS	29

#define pte_to_pgoff(pte)	(pte_val(pte) >> 2)
#define pgoff_to_pte(off)	__pte((off) << 2 | _PAGE_FILE)

/* Encode and de-code a swap entry */
#define __swp_type(x)			(((x).val >> 2) & 0x3f)
#define __swp_offset(x)			((x).val >> 8)
#define __swp_entry(type, offset) \
	((swp_entry_t) { ((type) << 2) | ((offset) << 8) })
#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x)		__pte((x).val)

static inline
int ptep_test_and_clear_dirty(struct vm_area_struct *vma, unsigned long addr,
			      pte_t *ptep)
{
	if (!pte_dirty(*ptep))
		return 0;
	return test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte);
}

static inline
int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr,
			      pte_t *ptep)
{
	if (!pte_young(*ptep))
		return 0;
	return test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte);
}

static inline
void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
	pte_val(*ptep) &= ~(__PAGE_PROT_WRITE|__PAGE_PROT_UWAUX);
}

static inline void ptep_mkdirty(pte_t *ptep)
{
	set_bit(_PAGE_BIT_DIRTY, &ptep->pte);
}

/*
 * Macro to mark a page protection value as "uncacheable".  On processors which
 * do not support it, this is a no-op.
 */
#define pgprot_noncached(prot)	__pgprot(pgprot_val(prot) | _PAGE_CACHE)


/*
 * Conversion functions: convert a page and protection to a page entry,
 * and a page entry and page directory to the page they refer to.
 */

#define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
#define mk_pte_huge(entry) \
	((entry).pte |= _PAGE_PRESENT | _PAGE_PSE | _PAGE_VALID)

static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
	pte_val(pte) &= _PAGE_CHG_MASK;
	pte_val(pte) |= pgprot_val(newprot);
	return pte;
}

#define page_pte(page)	page_pte_prot((page), __pgprot(0))

#define pmd_page_kernel(pmd) \
	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))

#define pmd_page(pmd)	pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)

#define pmd_large(pmd) \
	((pmd_val(pmd) & (_PAGE_PSE | _PAGE_PRESENT)) == \
	 (_PAGE_PSE | _PAGE_PRESENT))

/*
 * the pgd page can be thought of an array like this: pgd_t[PTRS_PER_PGD]
 *
 * this macro returns the index of the entry in the pgd page which would
 * control the given virtual address
 */
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))

/*
 * pgd_offset() returns a (pgd_t *)
 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
 */
#define pgd_offset(mm, address)	((mm)->pgd + pgd_index(address))

/*
 * a shortcut which implies the use of the kernel's pgd, instead
 * of a process's
 */
#define pgd_offset_k(address)	pgd_offset(&init_mm, address)

/*
 * the pmd page can be thought of an array like this: pmd_t[PTRS_PER_PMD]
 *
 * this macro returns the index of the entry in the pmd page which would
 * control the given virtual address
 */
#define pmd_index(address) \
	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))

/*
 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
 *
 * this macro returns the index of the entry in the pte page which would
 * control the given virtual address
 */
#define pte_index(address) \
	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))

#define pte_offset_kernel(dir, address) \
	((pte_t *) pmd_page_kernel(*(dir)) +  pte_index(address))

/*
 * Make a given kernel text page executable/non-executable.
 * Returns the previous executability setting of that page (which
 * is used to restore the previous state). Used by the SMP bootup code.
 * NOTE: this is an __init function for security reasons.
 */
static inline int set_kernel_exec(unsigned long vaddr, int enable)
{
	return 0;
}

#define pte_offset_map(dir, address) \
	((pte_t *) page_address(pmd_page(*(dir))) + pte_index(address))
#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
#define pte_unmap(pte)		do {} while (0)
#define pte_unmap_nested(pte)	do {} while (0)

/*
 * The MN10300 has external MMU info in the form of a TLB: this is adapted from
 * the kernel page tables containing the necessary information by tlb-mn10300.S
 */
extern void update_mmu_cache(struct vm_area_struct *vma,
			     unsigned long address, pte_t pte);

#endif /* !__ASSEMBLY__ */

#define kern_addr_valid(addr)	(1)

#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
	remap_pfn_range((vma), (vaddr), (pfn), (size), (prot))

#define MK_IOSPACE_PFN(space, pfn)	(pfn)
#define GET_IOSPACE(pfn)		0
#define GET_PFN(pfn)			(pfn)

#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTEP_MKDIRTY
#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>

#endif /* !__ASSEMBLY__ */

#endif /* _ASM_PGTABLE_H */