tools, slub: Fix off-by-one buffer corruption after readlink() call
[linux-2.6/linux-mips.git] / arch / frv / include / asm / pgtable.h
blob6bc241e4b4f8212b386758586693d58e32e3a426
1 /* pgtable.h: FR-V page table mangling
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
11 * Derived from:
12 * include/asm-m68knommu/pgtable.h
13 * include/asm-i386/pgtable.h
16 #ifndef _ASM_PGTABLE_H
17 #define _ASM_PGTABLE_H
19 #include <asm/mem-layout.h>
20 #include <asm/setup.h>
21 #include <asm/processor.h>
23 #ifndef __ASSEMBLY__
24 #include <linux/threads.h>
25 #include <linux/slab.h>
26 #include <linux/list.h>
27 #include <linux/spinlock.h>
28 #include <linux/sched.h>
29 struct vm_area_struct;
30 #endif
32 #ifndef __ASSEMBLY__
33 #if defined(CONFIG_HIGHPTE)
34 typedef unsigned long pte_addr_t;
35 #else
36 typedef pte_t *pte_addr_t;
37 #endif
38 #endif
40 /*****************************************************************************/
42 * MMU-less operation case first
44 #ifndef CONFIG_MMU
46 #define pgd_present(pgd) (1) /* pages are always present on NO_MM */
47 #define pgd_none(pgd) (0)
48 #define pgd_bad(pgd) (0)
49 #define pgd_clear(pgdp)
50 #define kern_addr_valid(addr) (1)
51 #define pmd_offset(a, b) ((void *) 0)
53 #define PAGE_NONE __pgprot(0) /* these mean nothing to NO_MM */
54 #define PAGE_SHARED __pgprot(0) /* these mean nothing to NO_MM */
55 #define PAGE_COPY __pgprot(0) /* these mean nothing to NO_MM */
56 #define PAGE_READONLY __pgprot(0) /* these mean nothing to NO_MM */
57 #define PAGE_KERNEL __pgprot(0) /* these mean nothing to NO_MM */
59 #define __swp_type(x) (0)
60 #define __swp_offset(x) (0)
61 #define __swp_entry(typ,off) ((swp_entry_t) { ((typ) | ((off) << 7)) })
62 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
63 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
65 #ifndef __ASSEMBLY__
66 static inline int pte_file(pte_t pte) { return 0; }
67 #endif
69 #define ZERO_PAGE(vaddr) ({ BUG(); NULL; })
71 #define swapper_pg_dir ((pgd_t *) NULL)
73 #define pgtable_cache_init() do {} while (0)
75 #include <asm-generic/pgtable.h>
77 #else /* !CONFIG_MMU */
78 /*****************************************************************************/
80 * then MMU operation
84 * ZERO_PAGE is a global shared page that is always zero: used
85 * for zero-mapped memory areas etc..
87 #ifndef __ASSEMBLY__
88 extern unsigned long empty_zero_page;
89 #define ZERO_PAGE(vaddr) virt_to_page(empty_zero_page)
90 #endif
93 * we use 2-level page tables, folding the PMD (mid-level table) into the PGE (top-level entry)
94 * [see Documentation/frv/mmu-layout.txt]
96 * Page Directory:
97 * - Size: 16KB
98 * - 64 PGEs per PGD
99 * - Each PGE holds 1 PUD and covers 64MB
101 * Page Upper Directory:
102 * - Size: 256B
103 * - 1 PUE per PUD
104 * - Each PUE holds 1 PMD and covers 64MB
106 * Page Mid-Level Directory
107 * - Size: 256B
108 * - 1 PME per PMD
109 * - Each PME holds 64 STEs, all of which point to separate chunks of the same Page Table
110 * - All STEs are instantiated at the same time
112 * Page Table
113 * - Size: 16KB
114 * - 4096 PTEs per PT
115 * - Each Linux PT is subdivided into 64 FR451 PT's, each of which holds 64 entries
117 * Pages
118 * - Size: 4KB
120 * total PTEs
121 * = 1 PML4E * 64 PGEs * 1 PUEs * 1 PMEs * 4096 PTEs
122 * = 1 PML4E * 64 PGEs * 64 STEs * 64 PTEs/FR451-PT
123 * = 262144 (or 256 * 1024)
125 #define PGDIR_SHIFT 26
126 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
127 #define PGDIR_MASK (~(PGDIR_SIZE - 1))
128 #define PTRS_PER_PGD 64
130 #define PUD_SHIFT 26
131 #define PTRS_PER_PUD 1
132 #define PUD_SIZE (1UL << PUD_SHIFT)
133 #define PUD_MASK (~(PUD_SIZE - 1))
134 #define PUE_SIZE 256
136 #define PMD_SHIFT 26
137 #define PMD_SIZE (1UL << PMD_SHIFT)
138 #define PMD_MASK (~(PMD_SIZE - 1))
139 #define PTRS_PER_PMD 1
140 #define PME_SIZE 256
142 #define __frv_PT_SIZE 256
144 #define PTRS_PER_PTE 4096
146 #define USER_PGDS_IN_LAST_PML4 (TASK_SIZE / PGDIR_SIZE)
147 #define FIRST_USER_ADDRESS 0
149 #define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
150 #define KERNEL_PGD_PTRS (PTRS_PER_PGD - USER_PGD_PTRS)
152 #define TWOLEVEL_PGDIR_SHIFT 26
153 #define BOOT_USER_PGD_PTRS (__PAGE_OFFSET >> TWOLEVEL_PGDIR_SHIFT)
154 #define BOOT_KERNEL_PGD_PTRS (PTRS_PER_PGD - BOOT_USER_PGD_PTRS)
156 #ifndef __ASSEMBLY__
158 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
160 #define pte_ERROR(e) \
161 printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte)
162 #define pmd_ERROR(e) \
163 printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
164 #define pud_ERROR(e) \
165 printk("%s:%d: bad pud %08lx.\n", __FILE__, __LINE__, pmd_val(pud_val(e)))
166 #define pgd_ERROR(e) \
167 printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pmd_val(pud_val(pgd_val(e))))
170 * Certain architectures need to do special things when PTEs
171 * within a page table are directly modified. Thus, the following
172 * hook is made available.
174 #define set_pte(pteptr, pteval) \
175 do { \
176 *(pteptr) = (pteval); \
177 asm volatile("dcf %M0" :: "U"(*pteptr)); \
178 } while(0)
179 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
182 * pgd_offset() returns a (pgd_t *)
183 * pgd_index() is used get the offset into the pgd page's array of pgd_t's;
185 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
188 * a shortcut which implies the use of the kernel's pgd, instead
189 * of a process's
191 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
194 * The "pgd_xxx()" functions here are trivial for a folded two-level
195 * setup: the pud is never bad, and a pud always exists (as it's folded
196 * into the pgd entry)
198 static inline int pgd_none(pgd_t pgd) { return 0; }
199 static inline int pgd_bad(pgd_t pgd) { return 0; }
200 static inline int pgd_present(pgd_t pgd) { return 1; }
201 static inline void pgd_clear(pgd_t *pgd) { }
203 #define pgd_populate(mm, pgd, pud) do { } while (0)
205 * (puds are folded into pgds so this doesn't get actually called,
206 * but the define is needed for a generic inline function.)
208 #define set_pgd(pgdptr, pgdval) \
209 do { \
210 memcpy((pgdptr), &(pgdval), sizeof(pgd_t)); \
211 asm volatile("dcf %M0" :: "U"(*(pgdptr))); \
212 } while(0)
214 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
216 return (pud_t *) pgd;
219 #define pgd_page(pgd) (pud_page((pud_t){ pgd }))
220 #define pgd_page_vaddr(pgd) (pud_page_vaddr((pud_t){ pgd }))
223 * allocating and freeing a pud is trivial: the 1-entry pud is
224 * inside the pgd, so has no extra memory associated with it.
226 #define pud_alloc_one(mm, address) NULL
227 #define pud_free(mm, x) do { } while (0)
228 #define __pud_free_tlb(tlb, x, address) do { } while (0)
231 * The "pud_xxx()" functions here are trivial for a folded two-level
232 * setup: the pmd is never bad, and a pmd always exists (as it's folded
233 * into the pud entry)
235 static inline int pud_none(pud_t pud) { return 0; }
236 static inline int pud_bad(pud_t pud) { return 0; }
237 static inline int pud_present(pud_t pud) { return 1; }
238 static inline void pud_clear(pud_t *pud) { }
240 #define pud_populate(mm, pmd, pte) do { } while (0)
243 * (pmds are folded into puds so this doesn't get actually called,
244 * but the define is needed for a generic inline function.)
246 #define set_pud(pudptr, pudval) set_pmd((pmd_t *)(pudptr), (pmd_t) { pudval })
248 #define pud_page(pud) (pmd_page((pmd_t){ pud }))
249 #define pud_page_vaddr(pud) (pmd_page_vaddr((pmd_t){ pud }))
252 * (pmds are folded into pgds so this doesn't get actually called,
253 * but the define is needed for a generic inline function.)
255 extern void __set_pmd(pmd_t *pmdptr, unsigned long __pmd);
257 #define set_pmd(pmdptr, pmdval) \
258 do { \
259 __set_pmd((pmdptr), (pmdval).ste[0]); \
260 } while(0)
262 #define __pmd_index(address) 0
264 static inline pmd_t *pmd_offset(pud_t *dir, unsigned long address)
266 return (pmd_t *) dir + __pmd_index(address);
269 #define pte_same(a, b) ((a).pte == (b).pte)
270 #define pte_page(x) (mem_map + ((unsigned long)(((x).pte >> PAGE_SHIFT))))
271 #define pte_none(x) (!(x).pte)
272 #define pte_pfn(x) ((unsigned long)(((x).pte >> PAGE_SHIFT)))
273 #define pfn_pte(pfn, prot) __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
274 #define pfn_pmd(pfn, prot) __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
276 #define VMALLOC_VMADDR(x) ((unsigned long) (x))
278 #endif /* !__ASSEMBLY__ */
281 * control flags in AMPR registers and TLB entries
283 #define _PAGE_BIT_PRESENT xAMPRx_V_BIT
284 #define _PAGE_BIT_WP DAMPRx_WP_BIT
285 #define _PAGE_BIT_NOCACHE xAMPRx_C_BIT
286 #define _PAGE_BIT_SUPER xAMPRx_S_BIT
287 #define _PAGE_BIT_ACCESSED xAMPRx_RESERVED8_BIT
288 #define _PAGE_BIT_DIRTY xAMPRx_M_BIT
289 #define _PAGE_BIT_NOTGLOBAL xAMPRx_NG_BIT
291 #define _PAGE_PRESENT xAMPRx_V
292 #define _PAGE_WP DAMPRx_WP
293 #define _PAGE_NOCACHE xAMPRx_C
294 #define _PAGE_SUPER xAMPRx_S
295 #define _PAGE_ACCESSED xAMPRx_RESERVED8 /* accessed if set */
296 #define _PAGE_DIRTY xAMPRx_M
297 #define _PAGE_NOTGLOBAL xAMPRx_NG
299 #define _PAGE_RESERVED_MASK (xAMPRx_RESERVED8 | xAMPRx_RESERVED13)
301 #define _PAGE_FILE 0x002 /* set:pagecache unset:swap */
302 #define _PAGE_PROTNONE 0x000 /* If not present */
304 #define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
306 #define __PGPROT_BASE \
307 (_PAGE_PRESENT | xAMPRx_SS_16Kb | xAMPRx_D | _PAGE_NOTGLOBAL | _PAGE_ACCESSED)
309 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
310 #define PAGE_SHARED __pgprot(__PGPROT_BASE)
311 #define PAGE_COPY __pgprot(__PGPROT_BASE | _PAGE_WP)
312 #define PAGE_READONLY __pgprot(__PGPROT_BASE | _PAGE_WP)
314 #define __PAGE_KERNEL (__PGPROT_BASE | _PAGE_SUPER | _PAGE_DIRTY)
315 #define __PAGE_KERNEL_NOCACHE (__PGPROT_BASE | _PAGE_SUPER | _PAGE_DIRTY | _PAGE_NOCACHE)
316 #define __PAGE_KERNEL_RO (__PGPROT_BASE | _PAGE_SUPER | _PAGE_DIRTY | _PAGE_WP)
318 #define MAKE_GLOBAL(x) __pgprot((x) & ~_PAGE_NOTGLOBAL)
320 #define PAGE_KERNEL MAKE_GLOBAL(__PAGE_KERNEL)
321 #define PAGE_KERNEL_RO MAKE_GLOBAL(__PAGE_KERNEL_RO)
322 #define PAGE_KERNEL_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
324 #define _PAGE_TABLE (_PAGE_PRESENT | xAMPRx_SS_16Kb)
326 #ifndef __ASSEMBLY__
329 * The FR451 can do execute protection by virtue of having separate TLB miss handlers for
330 * instruction access and for data access. However, we don't have enough reserved bits to say
331 * "execute only", so we don't bother. If you can read it, you can execute it and vice versa.
333 #define __P000 PAGE_NONE
334 #define __P001 PAGE_READONLY
335 #define __P010 PAGE_COPY
336 #define __P011 PAGE_COPY
337 #define __P100 PAGE_READONLY
338 #define __P101 PAGE_READONLY
339 #define __P110 PAGE_COPY
340 #define __P111 PAGE_COPY
342 #define __S000 PAGE_NONE
343 #define __S001 PAGE_READONLY
344 #define __S010 PAGE_SHARED
345 #define __S011 PAGE_SHARED
346 #define __S100 PAGE_READONLY
347 #define __S101 PAGE_READONLY
348 #define __S110 PAGE_SHARED
349 #define __S111 PAGE_SHARED
352 * Define this to warn about kernel memory accesses that are
353 * done without a 'access_ok(VERIFY_WRITE,..)'
355 #undef TEST_ACCESS_OK
357 #define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
358 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
360 #define pmd_none(x) (!pmd_val(x))
361 #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
362 #define pmd_bad(x) (pmd_val(x) & xAMPRx_SS)
363 #define pmd_clear(xp) do { __set_pmd(xp, 0); } while(0)
365 #define pmd_page_vaddr(pmd) \
366 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
368 #ifndef CONFIG_DISCONTIGMEM
369 #define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
370 #endif
372 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
375 * The following only work if pte_present() is true.
376 * Undefined behaviour if not..
378 static inline int pte_dirty(pte_t pte) { return (pte).pte & _PAGE_DIRTY; }
379 static inline int pte_young(pte_t pte) { return (pte).pte & _PAGE_ACCESSED; }
380 static inline int pte_write(pte_t pte) { return !((pte).pte & _PAGE_WP); }
381 static inline int pte_special(pte_t pte) { return 0; }
383 static inline pte_t pte_mkclean(pte_t pte) { (pte).pte &= ~_PAGE_DIRTY; return pte; }
384 static inline pte_t pte_mkold(pte_t pte) { (pte).pte &= ~_PAGE_ACCESSED; return pte; }
385 static inline pte_t pte_wrprotect(pte_t pte) { (pte).pte |= _PAGE_WP; return pte; }
386 static inline pte_t pte_mkdirty(pte_t pte) { (pte).pte |= _PAGE_DIRTY; return pte; }
387 static inline pte_t pte_mkyoung(pte_t pte) { (pte).pte |= _PAGE_ACCESSED; return pte; }
388 static inline pte_t pte_mkwrite(pte_t pte) { (pte).pte &= ~_PAGE_WP; return pte; }
389 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
391 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
393 int i = test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep);
394 asm volatile("dcf %M0" :: "U"(*ptep));
395 return i;
398 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
400 unsigned long x = xchg(&ptep->pte, 0);
401 asm volatile("dcf %M0" :: "U"(*ptep));
402 return __pte(x);
405 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
407 set_bit(_PAGE_BIT_WP, ptep);
408 asm volatile("dcf %M0" :: "U"(*ptep));
412 * Macro to mark a page protection value as "uncacheable"
414 #define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_NOCACHE))
417 * Conversion functions: convert a page and protection to a page entry,
418 * and a page entry and page directory to the page they refer to.
421 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
422 #define mk_pte_huge(entry) ((entry).pte_low |= _PAGE_PRESENT | _PAGE_PSE)
424 /* This takes a physical page address that is used by the remapping functions */
425 #define mk_pte_phys(physpage, pgprot) pfn_pte((physpage) >> PAGE_SHIFT, pgprot)
427 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
429 pte.pte &= _PAGE_CHG_MASK;
430 pte.pte |= pgprot_val(newprot);
431 return pte;
434 /* to find an entry in a page-table-directory. */
435 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
436 #define pgd_index_k(addr) pgd_index(addr)
438 /* Find an entry in the bottom-level page table.. */
439 #define __pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
442 * the pte page can be thought of an array like this: pte_t[PTRS_PER_PTE]
444 * this macro returns the index of the entry in the pte page which would
445 * control the given virtual address
447 #define pte_index(address) \
448 (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
449 #define pte_offset_kernel(dir, address) \
450 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
452 #if defined(CONFIG_HIGHPTE)
453 #define pte_offset_map(dir, address) \
454 ((pte_t *)kmap_atomic(pmd_page(*(dir))) + pte_index(address))
455 #define pte_unmap(pte) kunmap_atomic(pte)
456 #else
457 #define pte_offset_map(dir, address) \
458 ((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
459 #define pte_unmap(pte) do { } while (0)
460 #endif
463 * Handle swap and file entries
464 * - the PTE is encoded in the following format:
465 * bit 0: Must be 0 (!_PAGE_PRESENT)
466 * bit 1: Type: 0 for swap, 1 for file (_PAGE_FILE)
467 * bits 2-7: Swap type
468 * bits 8-31: Swap offset
469 * bits 2-31: File pgoff
471 #define __swp_type(x) (((x).val >> 2) & 0x1f)
472 #define __swp_offset(x) ((x).val >> 8)
473 #define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 2) | ((offset) << 8) })
474 #define __pte_to_swp_entry(_pte) ((swp_entry_t) { (_pte).pte })
475 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
477 static inline int pte_file(pte_t pte)
479 return pte.pte & _PAGE_FILE;
482 #define PTE_FILE_MAX_BITS 29
484 #define pte_to_pgoff(PTE) ((PTE).pte >> 2)
485 #define pgoff_to_pte(off) __pte((off) << 2 | _PAGE_FILE)
487 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
488 #define PageSkip(page) (0)
489 #define kern_addr_valid(addr) (1)
491 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
492 remap_pfn_range(vma, vaddr, pfn, size, prot)
494 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
495 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
496 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
497 #define __HAVE_ARCH_PTE_SAME
498 #include <asm-generic/pgtable.h>
501 * preload information about a newly instantiated PTE into the SCR0/SCR1 PGE cache
503 static inline void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
505 struct mm_struct *mm;
506 unsigned long ampr;
508 mm = current->mm;
509 if (mm) {
510 pgd_t *pge = pgd_offset(mm, address);
511 pud_t *pue = pud_offset(pge, address);
512 pmd_t *pme = pmd_offset(pue, address);
514 ampr = pme->ste[0] & 0xffffff00;
515 ampr |= xAMPRx_L | xAMPRx_SS_16Kb | xAMPRx_S | xAMPRx_C |
516 xAMPRx_V;
517 } else {
518 address = ULONG_MAX;
519 ampr = 0;
522 asm volatile("movgs %0,scr0\n"
523 "movgs %0,scr1\n"
524 "movgs %1,dampr4\n"
525 "movgs %1,dampr5\n"
527 : "r"(address), "r"(ampr)
531 #ifdef CONFIG_PROC_FS
532 extern char *proc_pid_status_frv_cxnr(struct mm_struct *mm, char *buffer);
533 #endif
535 extern void __init pgtable_cache_init(void);
537 #endif /* !__ASSEMBLY__ */
538 #endif /* !CONFIG_MMU */
540 #ifndef __ASSEMBLY__
541 extern void __init paging_init(void);
542 #endif /* !__ASSEMBLY__ */
544 #endif /* _ASM_PGTABLE_H */