• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 #ifndef _ASM_IA64_PGTABLE_H
2 #define _ASM_IA64_PGTABLE_H
3 
4 /*
5  * This file contains the functions and defines necessary to modify and use
6  * the IA-64 page table tree.
7  *
8  * This hopefully works with any (fixed) IA-64 page-size, as defined
9  * in <asm/page.h>.
10  *
11  * Copyright (C) 1998-2005 Hewlett-Packard Co
12  *	David Mosberger-Tang <davidm@hpl.hp.com>
13  */
14 
15 
16 #include <asm/mman.h>
17 #include <asm/page.h>
18 #include <asm/processor.h>
19 #include <asm/types.h>
20 
21 #define IA64_MAX_PHYS_BITS	50	/* max. number of physical address bits (architected) */
22 
23 /*
24  * First, define the various bits in a PTE.  Note that the PTE format
25  * matches the VHPT short format, the firt doubleword of the VHPD long
26  * format, and the first doubleword of the TLB insertion format.
27  */
28 #define _PAGE_P_BIT		0
29 #define _PAGE_A_BIT		5
30 #define _PAGE_D_BIT		6
31 
32 #define _PAGE_P			(1 << _PAGE_P_BIT)	/* page present bit */
33 #define _PAGE_MA_WB		(0x0 <<  2)	/* write back memory attribute */
34 #define _PAGE_MA_UC		(0x4 <<  2)	/* uncacheable memory attribute */
35 #define _PAGE_MA_UCE		(0x5 <<  2)	/* UC exported attribute */
36 #define _PAGE_MA_WC		(0x6 <<  2)	/* write coalescing memory attribute */
37 #define _PAGE_MA_NAT		(0x7 <<  2)	/* not-a-thing attribute */
38 #define _PAGE_MA_MASK		(0x7 <<  2)
39 #define _PAGE_PL_0		(0 <<  7)	/* privilege level 0 (kernel) */
40 #define _PAGE_PL_1		(1 <<  7)	/* privilege level 1 (unused) */
41 #define _PAGE_PL_2		(2 <<  7)	/* privilege level 2 (unused) */
42 #define _PAGE_PL_3		(3 <<  7)	/* privilege level 3 (user) */
43 #define _PAGE_PL_MASK		(3 <<  7)
44 #define _PAGE_AR_R		(0 <<  9)	/* read only */
45 #define _PAGE_AR_RX		(1 <<  9)	/* read & execute */
46 #define _PAGE_AR_RW		(2 <<  9)	/* read & write */
47 #define _PAGE_AR_RWX		(3 <<  9)	/* read, write & execute */
48 #define _PAGE_AR_R_RW		(4 <<  9)	/* read / read & write */
49 #define _PAGE_AR_RX_RWX		(5 <<  9)	/* read & exec / read, write & exec */
50 #define _PAGE_AR_RWX_RW		(6 <<  9)	/* read, write & exec / read & write */
51 #define _PAGE_AR_X_RX		(7 <<  9)	/* exec & promote / read & exec */
52 #define _PAGE_AR_MASK		(7 <<  9)
53 #define _PAGE_AR_SHIFT		9
54 #define _PAGE_A			(1 << _PAGE_A_BIT)	/* page accessed bit */
55 #define _PAGE_D			(1 << _PAGE_D_BIT)	/* page dirty bit */
56 #define _PAGE_PPN_MASK		(((__IA64_UL(1) << IA64_MAX_PHYS_BITS) - 1) & ~0xfffUL)
57 #define _PAGE_ED		(__IA64_UL(1) << 52)	/* exception deferral */
58 #define _PAGE_PROTNONE		(__IA64_UL(1) << 63)
59 
60 #define _PFN_MASK		_PAGE_PPN_MASK
61 /* Mask of bits which may be changed by pte_modify(); the odd bits are there for _PAGE_PROTNONE */
62 #define _PAGE_CHG_MASK	(_PAGE_P | _PAGE_PROTNONE | _PAGE_PL_MASK | _PAGE_AR_MASK | _PAGE_ED)
63 
64 #define _PAGE_SIZE_4K	12
65 #define _PAGE_SIZE_8K	13
66 #define _PAGE_SIZE_16K	14
67 #define _PAGE_SIZE_64K	16
68 #define _PAGE_SIZE_256K	18
69 #define _PAGE_SIZE_1M	20
70 #define _PAGE_SIZE_4M	22
71 #define _PAGE_SIZE_16M	24
72 #define _PAGE_SIZE_64M	26
73 #define _PAGE_SIZE_256M	28
74 #define _PAGE_SIZE_1G	30
75 #define _PAGE_SIZE_4G	32
76 
77 #define __ACCESS_BITS		_PAGE_ED | _PAGE_A | _PAGE_P | _PAGE_MA_WB
78 #define __DIRTY_BITS_NO_ED	_PAGE_A | _PAGE_P | _PAGE_D | _PAGE_MA_WB
79 #define __DIRTY_BITS		_PAGE_ED | __DIRTY_BITS_NO_ED
80 
81 /*
82  * How many pointers will a page table level hold expressed in shift
83  */
84 #define PTRS_PER_PTD_SHIFT	(PAGE_SHIFT-3)
85 
86 /*
87  * Definitions for fourth level:
88  */
89 #define PTRS_PER_PTE	(__IA64_UL(1) << (PTRS_PER_PTD_SHIFT))
90 
91 /*
92  * Definitions for third level:
93  *
94  * PMD_SHIFT determines the size of the area a third-level page table
95  * can map.
96  */
97 #define PMD_SHIFT	(PAGE_SHIFT + (PTRS_PER_PTD_SHIFT))
98 #define PMD_SIZE	(1UL << PMD_SHIFT)
99 #define PMD_MASK	(~(PMD_SIZE-1))
100 #define PTRS_PER_PMD	(1UL << (PTRS_PER_PTD_SHIFT))
101 
102 #if CONFIG_PGTABLE_LEVELS == 4
103 /*
104  * Definitions for second level:
105  *
106  * PUD_SHIFT determines the size of the area a second-level page table
107  * can map.
108  */
109 #define PUD_SHIFT	(PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
110 #define PUD_SIZE	(1UL << PUD_SHIFT)
111 #define PUD_MASK	(~(PUD_SIZE-1))
112 #define PTRS_PER_PUD	(1UL << (PTRS_PER_PTD_SHIFT))
113 #endif
114 
115 /*
116  * Definitions for first level:
117  *
118  * PGDIR_SHIFT determines what a first-level page table entry can map.
119  */
120 #if CONFIG_PGTABLE_LEVELS == 4
121 #define PGDIR_SHIFT		(PUD_SHIFT + (PTRS_PER_PTD_SHIFT))
122 #else
123 #define PGDIR_SHIFT		(PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
124 #endif
125 #define PGDIR_SIZE		(__IA64_UL(1) << PGDIR_SHIFT)
126 #define PGDIR_MASK		(~(PGDIR_SIZE-1))
127 #define PTRS_PER_PGD_SHIFT	PTRS_PER_PTD_SHIFT
128 #define PTRS_PER_PGD		(1UL << PTRS_PER_PGD_SHIFT)
129 #define USER_PTRS_PER_PGD	(5*PTRS_PER_PGD/8)	/* regions 0-4 are user regions */
130 #define FIRST_USER_ADDRESS	0UL
131 
132 /*
133  * All the normal masks have the "page accessed" bits on, as any time
134  * they are used, the page is accessed. They are cleared only by the
135  * page-out routines.
136  */
137 #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_A)
138 #define PAGE_SHARED	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RW)
139 #define PAGE_READONLY	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
140 #define PAGE_COPY	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
141 #define PAGE_COPY_EXEC	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
142 #define PAGE_GATE	__pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_X_RX)
143 #define PAGE_KERNEL	__pgprot(__DIRTY_BITS  | _PAGE_PL_0 | _PAGE_AR_RWX)
144 #define PAGE_KERNELRX	__pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_RX)
145 #define PAGE_KERNEL_UC	__pgprot(__DIRTY_BITS  | _PAGE_PL_0 | _PAGE_AR_RWX | \
146 				 _PAGE_MA_UC)
147 
148 # ifndef __ASSEMBLY__
149 
150 #include <linux/sched.h>	/* for mm_struct */
151 #include <linux/bitops.h>
152 #include <asm/cacheflush.h>
153 #include <asm/mmu_context.h>
154 
155 /*
156  * Next come the mappings that determine how mmap() protection bits
157  * (PROT_EXEC, PROT_READ, PROT_WRITE, PROT_NONE) get implemented.  The
158  * _P version gets used for a private shared memory segment, the _S
159  * version gets used for a shared memory segment with MAP_SHARED on.
160  * In a private shared memory segment, we do a copy-on-write if a task
161  * attempts to write to the page.
162  */
163 	/* xwr */
164 #define __P000	PAGE_NONE
165 #define __P001	PAGE_READONLY
166 #define __P010	PAGE_READONLY	/* write to priv pg -> copy & make writable */
167 #define __P011	PAGE_READONLY	/* ditto */
168 #define __P100	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
169 #define __P101	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
170 #define __P110	PAGE_COPY_EXEC
171 #define __P111	PAGE_COPY_EXEC
172 
173 #define __S000	PAGE_NONE
174 #define __S001	PAGE_READONLY
175 #define __S010	PAGE_SHARED	/* we don't have (and don't need) write-only */
176 #define __S011	PAGE_SHARED
177 #define __S100	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
178 #define __S101	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
179 #define __S110	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
180 #define __S111	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
181 
182 #define pgd_ERROR(e)	printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
183 #if CONFIG_PGTABLE_LEVELS == 4
184 #define pud_ERROR(e)	printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
185 #endif
186 #define pmd_ERROR(e)	printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
187 #define pte_ERROR(e)	printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
188 
189 
190 /*
191  * Some definitions to translate between mem_map, PTEs, and page addresses:
192  */
193 
194 
195 /* Quick test to see if ADDR is a (potentially) valid physical address. */
196 static inline long
ia64_phys_addr_valid(unsigned long addr)197 ia64_phys_addr_valid (unsigned long addr)
198 {
199 	return (addr & (local_cpu_data->unimpl_pa_mask)) == 0;
200 }
201 
202 /*
203  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
204  * memory.  For the return value to be meaningful, ADDR must be >=
205  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
206  * require a hash-, or multi-level tree-lookup or something of that
207  * sort) but it guarantees to return TRUE only if accessing the page
208  * at that address does not cause an error.  Note that there may be
209  * addresses for which kern_addr_valid() returns FALSE even though an
210  * access would not cause an error (e.g., this is typically true for
211  * memory mapped I/O regions.
212  *
213  * XXX Need to implement this for IA-64.
214  */
215 #define kern_addr_valid(addr)	(1)
216 
217 
218 /*
219  * Now come the defines and routines to manage and access the three-level
220  * page table.
221  */
222 
223 
224 #define VMALLOC_START		(RGN_BASE(RGN_GATE) + 0x200000000UL)
225 #ifdef CONFIG_VIRTUAL_MEM_MAP
226 # define VMALLOC_END_INIT	(RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
227 extern unsigned long VMALLOC_END;
228 #else
229 #if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP)
230 /* SPARSEMEM_VMEMMAP uses half of vmalloc... */
231 # define VMALLOC_END		(RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10)))
232 # define vmemmap		((struct page *)VMALLOC_END)
233 #else
234 # define VMALLOC_END		(RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
235 #endif
236 #endif
237 
238 /* fs/proc/kcore.c */
239 #define	kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE))
240 #define	kc_offset_to_vaddr(o) ((o) + RGN_BASE(RGN_GATE))
241 
242 #define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3)
243 #define RGN_MAP_LIMIT	((1UL << RGN_MAP_SHIFT) - PAGE_SIZE)	/* per region addr limit */
244 
245 /*
246  * Conversion functions: convert page frame number (pfn) and a protection value to a page
247  * table entry (pte).
248  */
249 #define pfn_pte(pfn, pgprot) \
250 ({ pte_t __pte; pte_val(__pte) = ((pfn) << PAGE_SHIFT) | pgprot_val(pgprot); __pte; })
251 
252 /* Extract pfn from pte.  */
253 #define pte_pfn(_pte)		((pte_val(_pte) & _PFN_MASK) >> PAGE_SHIFT)
254 
255 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
256 
257 /* This takes a physical page address that is used by the remapping functions */
258 #define mk_pte_phys(physpage, pgprot) \
259 ({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
260 
261 #define pte_modify(_pte, newprot) \
262 	(__pte((pte_val(_pte) & ~_PAGE_CHG_MASK) | (pgprot_val(newprot) & _PAGE_CHG_MASK)))
263 
264 #define pte_none(pte) 			(!pte_val(pte))
265 #define pte_present(pte)		(pte_val(pte) & (_PAGE_P | _PAGE_PROTNONE))
266 #define pte_clear(mm,addr,pte)		(pte_val(*(pte)) = 0UL)
267 /* pte_page() returns the "struct page *" corresponding to the PTE: */
268 #define pte_page(pte)			virt_to_page(((pte_val(pte) & _PFN_MASK) + PAGE_OFFSET))
269 
270 #define pmd_none(pmd)			(!pmd_val(pmd))
271 #define pmd_bad(pmd)			(!ia64_phys_addr_valid(pmd_val(pmd)))
272 #define pmd_present(pmd)		(pmd_val(pmd) != 0UL)
273 #define pmd_clear(pmdp)			(pmd_val(*(pmdp)) = 0UL)
274 #define pmd_page_vaddr(pmd)		((unsigned long) __va(pmd_val(pmd) & _PFN_MASK))
275 #define pmd_page(pmd)			virt_to_page((pmd_val(pmd) + PAGE_OFFSET))
276 
277 #define pud_none(pud)			(!pud_val(pud))
278 #define pud_bad(pud)			(!ia64_phys_addr_valid(pud_val(pud)))
279 #define pud_present(pud)		(pud_val(pud) != 0UL)
280 #define pud_clear(pudp)			(pud_val(*(pudp)) = 0UL)
281 #define pud_page_vaddr(pud)		((unsigned long) __va(pud_val(pud) & _PFN_MASK))
282 #define pud_page(pud)			virt_to_page((pud_val(pud) + PAGE_OFFSET))
283 
284 #if CONFIG_PGTABLE_LEVELS == 4
285 #define pgd_none(pgd)			(!pgd_val(pgd))
286 #define pgd_bad(pgd)			(!ia64_phys_addr_valid(pgd_val(pgd)))
287 #define pgd_present(pgd)		(pgd_val(pgd) != 0UL)
288 #define pgd_clear(pgdp)			(pgd_val(*(pgdp)) = 0UL)
289 #define pgd_page_vaddr(pgd)		((unsigned long) __va(pgd_val(pgd) & _PFN_MASK))
290 #define pgd_page(pgd)			virt_to_page((pgd_val(pgd) + PAGE_OFFSET))
291 #endif
292 
293 /*
294  * The following have defined behavior only work if pte_present() is true.
295  */
296 #define pte_write(pte)	((unsigned) (((pte_val(pte) & _PAGE_AR_MASK) >> _PAGE_AR_SHIFT) - 2) <= 4)
297 #define pte_exec(pte)		((pte_val(pte) & _PAGE_AR_RX) != 0)
298 #define pte_dirty(pte)		((pte_val(pte) & _PAGE_D) != 0)
299 #define pte_young(pte)		((pte_val(pte) & _PAGE_A) != 0)
300 #define pte_special(pte)	0
301 
302 /*
303  * Note: we convert AR_RWX to AR_RX and AR_RW to AR_R by clearing the 2nd bit in the
304  * access rights:
305  */
306 #define pte_wrprotect(pte)	(__pte(pte_val(pte) & ~_PAGE_AR_RW))
307 #define pte_mkwrite(pte)	(__pte(pte_val(pte) | _PAGE_AR_RW))
308 #define pte_mkold(pte)		(__pte(pte_val(pte) & ~_PAGE_A))
309 #define pte_mkyoung(pte)	(__pte(pte_val(pte) | _PAGE_A))
310 #define pte_mkclean(pte)	(__pte(pte_val(pte) & ~_PAGE_D))
311 #define pte_mkdirty(pte)	(__pte(pte_val(pte) | _PAGE_D))
312 #define pte_mkhuge(pte)		(__pte(pte_val(pte)))
313 #define pte_mkspecial(pte)	(pte)
314 
315 /*
316  * Because ia64's Icache and Dcache is not coherent (on a cpu), we need to
317  * sync icache and dcache when we insert *new* executable page.
318  *  __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache
319  * if necessary.
320  *
321  *  set_pte() is also called by the kernel, but we can expect that the kernel
322  *  flushes icache explicitly if necessary.
323  */
324 #define pte_present_exec_user(pte)\
325 	((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \
326 		(_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX))
327 
328 extern void __ia64_sync_icache_dcache(pte_t pteval);
set_pte(pte_t * ptep,pte_t pteval)329 static inline void set_pte(pte_t *ptep, pte_t pteval)
330 {
331 	/* page is present && page is user  && page is executable
332 	 * && (page swapin or new page or page migraton
333 	 *	|| copy_on_write with page copying.)
334 	 */
335 	if (pte_present_exec_user(pteval) &&
336 	    (!pte_present(*ptep) ||
337 		pte_pfn(*ptep) != pte_pfn(pteval)))
338 		/* load_module() calles flush_icache_range() explicitly*/
339 		__ia64_sync_icache_dcache(pteval);
340 	*ptep = pteval;
341 }
342 
343 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
344 
345 /*
346  * Make page protection values cacheable, uncacheable, or write-
347  * combining.  Note that "protection" is really a misnomer here as the
348  * protection value contains the memory attribute bits, dirty bits, and
349  * various other bits as well.
350  */
351 #define pgprot_cacheable(prot)		__pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WB)
352 #define pgprot_noncached(prot)		__pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_UC)
353 #define pgprot_writecombine(prot)	__pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WC)
354 
355 struct file;
356 extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
357 				     unsigned long size, pgprot_t vma_prot);
358 #define __HAVE_PHYS_MEM_ACCESS_PROT
359 
360 static inline unsigned long
pgd_index(unsigned long address)361 pgd_index (unsigned long address)
362 {
363 	unsigned long region = address >> 61;
364 	unsigned long l1index = (address >> PGDIR_SHIFT) & ((PTRS_PER_PGD >> 3) - 1);
365 
366 	return (region << (PAGE_SHIFT - 6)) | l1index;
367 }
368 
369 /* The offset in the 1-level directory is given by the 3 region bits
370    (61..63) and the level-1 bits.  */
371 static inline pgd_t*
pgd_offset(const struct mm_struct * mm,unsigned long address)372 pgd_offset (const struct mm_struct *mm, unsigned long address)
373 {
374 	return mm->pgd + pgd_index(address);
375 }
376 
377 /* In the kernel's mapped region we completely ignore the region number
378    (since we know it's in region number 5). */
379 #define pgd_offset_k(addr) \
380 	(init_mm.pgd + (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)))
381 
382 /* Look up a pgd entry in the gate area.  On IA-64, the gate-area
383    resides in the kernel-mapped segment, hence we use pgd_offset_k()
384    here.  */
385 #define pgd_offset_gate(mm, addr)	pgd_offset_k(addr)
386 
387 #if CONFIG_PGTABLE_LEVELS == 4
388 /* Find an entry in the second-level page table.. */
389 #define pud_offset(dir,addr) \
390 	((pud_t *) pgd_page_vaddr(*(dir)) + (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)))
391 #endif
392 
393 /* Find an entry in the third-level page table.. */
394 #define pmd_offset(dir,addr) \
395 	((pmd_t *) pud_page_vaddr(*(dir)) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
396 
397 /*
398  * Find an entry in the third-level page table.  This looks more complicated than it
399  * should be because some platforms place page tables in high memory.
400  */
401 #define pte_index(addr)	 	(((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
402 #define pte_offset_kernel(dir,addr)	((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
403 #define pte_offset_map(dir,addr)	pte_offset_kernel(dir, addr)
404 #define pte_unmap(pte)			do { } while (0)
405 
406 /* atomic versions of the some PTE manipulations: */
407 
408 static inline int
ptep_test_and_clear_young(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep)409 ptep_test_and_clear_young (struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
410 {
411 #ifdef CONFIG_SMP
412 	if (!pte_young(*ptep))
413 		return 0;
414 	return test_and_clear_bit(_PAGE_A_BIT, ptep);
415 #else
416 	pte_t pte = *ptep;
417 	if (!pte_young(pte))
418 		return 0;
419 	set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
420 	return 1;
421 #endif
422 }
423 
424 static inline pte_t
ptep_get_and_clear(struct mm_struct * mm,unsigned long addr,pte_t * ptep)425 ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
426 {
427 #ifdef CONFIG_SMP
428 	return __pte(xchg((long *) ptep, 0));
429 #else
430 	pte_t pte = *ptep;
431 	pte_clear(mm, addr, ptep);
432 	return pte;
433 #endif
434 }
435 
436 static inline void
ptep_set_wrprotect(struct mm_struct * mm,unsigned long addr,pte_t * ptep)437 ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
438 {
439 #ifdef CONFIG_SMP
440 	unsigned long new, old;
441 
442 	do {
443 		old = pte_val(*ptep);
444 		new = pte_val(pte_wrprotect(__pte (old)));
445 	} while (cmpxchg((unsigned long *) ptep, old, new) != old);
446 #else
447 	pte_t old_pte = *ptep;
448 	set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
449 #endif
450 }
451 
452 static inline int
pte_same(pte_t a,pte_t b)453 pte_same (pte_t a, pte_t b)
454 {
455 	return pte_val(a) == pte_val(b);
456 }
457 
458 #define update_mmu_cache(vma, address, ptep) do { } while (0)
459 
460 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
461 extern void paging_init (void);
462 
463 /*
464  * Note: The macros below rely on the fact that MAX_SWAPFILES_SHIFT <= number of
465  *	 bits in the swap-type field of the swap pte.  It would be nice to
466  *	 enforce that, but we can't easily include <linux/swap.h> here.
467  *	 (Of course, better still would be to define MAX_SWAPFILES_SHIFT here...).
468  *
469  * Format of swap pte:
470  *	bit   0   : present bit (must be zero)
471  *	bits  1- 7: swap-type
472  *	bits  8-62: swap offset
473  *	bit  63   : _PAGE_PROTNONE bit
474  */
475 #define __swp_type(entry)		(((entry).val >> 1) & 0x7f)
476 #define __swp_offset(entry)		(((entry).val << 1) >> 9)
477 #define __swp_entry(type,offset)	((swp_entry_t) { ((type) << 1) | ((long) (offset) << 8) })
478 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
479 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
480 
481 /*
482  * ZERO_PAGE is a global shared page that is always zero: used
483  * for zero-mapped memory areas etc..
484  */
485 extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
486 extern struct page *zero_page_memmap_ptr;
487 #define ZERO_PAGE(vaddr) (zero_page_memmap_ptr)
488 
489 /* We provide our own get_unmapped_area to cope with VA holes for userland */
490 #define HAVE_ARCH_UNMAPPED_AREA
491 
492 #ifdef CONFIG_HUGETLB_PAGE
493 #define HUGETLB_PGDIR_SHIFT	(HPAGE_SHIFT + 2*(PAGE_SHIFT-3))
494 #define HUGETLB_PGDIR_SIZE	(__IA64_UL(1) << HUGETLB_PGDIR_SHIFT)
495 #define HUGETLB_PGDIR_MASK	(~(HUGETLB_PGDIR_SIZE-1))
496 #endif
497 
498 
499 #define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
500 /*
501  * Update PTEP with ENTRY, which is guaranteed to be a less
502  * restrictive PTE.  That is, ENTRY may have the ACCESSED, DIRTY, and
503  * WRITABLE bits turned on, when the value at PTEP did not.  The
504  * WRITABLE bit may only be turned if SAFELY_WRITABLE is TRUE.
505  *
506  * SAFELY_WRITABLE is TRUE if we can update the value at PTEP without
507  * having to worry about races.  On SMP machines, there are only two
508  * cases where this is true:
509  *
510  *	(1) *PTEP has the PRESENT bit turned OFF
511  *	(2) ENTRY has the DIRTY bit turned ON
512  *
513  * On ia64, we could implement this routine with a cmpxchg()-loop
514  * which ORs in the _PAGE_A/_PAGE_D bit if they're set in ENTRY.
515  * However, like on x86, we can get a more streamlined version by
516  * observing that it is OK to drop ACCESSED bit updates when
517  * SAFELY_WRITABLE is FALSE.  Besides being rare, all that would do is
518  * result in an extra Access-bit fault, which would then turn on the
519  * ACCESSED bit in the low-level fault handler (iaccess_bit or
520  * daccess_bit in ivt.S).
521  */
522 #ifdef CONFIG_SMP
523 # define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
524 ({									\
525 	int __changed = !pte_same(*(__ptep), __entry);			\
526 	if (__changed && __safely_writable) {				\
527 		set_pte(__ptep, __entry);				\
528 		flush_tlb_page(__vma, __addr);				\
529 	}								\
530 	__changed;							\
531 })
532 #else
533 # define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
534 ({									\
535 	int __changed = !pte_same(*(__ptep), __entry);			\
536 	if (__changed) {						\
537 		set_pte_at((__vma)->vm_mm, (__addr), __ptep, __entry);	\
538 		flush_tlb_page(__vma, __addr);				\
539 	}								\
540 	__changed;							\
541 })
542 #endif
543 
544 #  ifdef CONFIG_VIRTUAL_MEM_MAP
545   /* arch mem_map init routine is needed due to holes in a virtual mem_map */
546 #   define __HAVE_ARCH_MEMMAP_INIT
547     extern void memmap_init (unsigned long size, int nid, unsigned long zone,
548 			     unsigned long start_pfn);
549 #  endif /* CONFIG_VIRTUAL_MEM_MAP */
550 # endif /* !__ASSEMBLY__ */
551 
552 /*
553  * Identity-mapped regions use a large page size.  We'll call such large pages
554  * "granules".  If you can think of a better name that's unambiguous, let me
555  * know...
556  */
557 #if defined(CONFIG_IA64_GRANULE_64MB)
558 # define IA64_GRANULE_SHIFT	_PAGE_SIZE_64M
559 #elif defined(CONFIG_IA64_GRANULE_16MB)
560 # define IA64_GRANULE_SHIFT	_PAGE_SIZE_16M
561 #endif
562 #define IA64_GRANULE_SIZE	(1 << IA64_GRANULE_SHIFT)
563 /*
564  * log2() of the page size we use to map the kernel image (IA64_TR_KERNEL):
565  */
566 #define KERNEL_TR_PAGE_SHIFT	_PAGE_SIZE_64M
567 #define KERNEL_TR_PAGE_SIZE	(1 << KERNEL_TR_PAGE_SHIFT)
568 
569 /*
570  * No page table caches to initialise
571  */
572 #define pgtable_cache_init()	do { } while (0)
573 
574 /* These tell get_user_pages() that the first gate page is accessible from user-level.  */
575 #define FIXADDR_USER_START	GATE_ADDR
576 #ifdef HAVE_BUGGY_SEGREL
577 # define FIXADDR_USER_END	(GATE_ADDR + 2*PAGE_SIZE)
578 #else
579 # define FIXADDR_USER_END	(GATE_ADDR + 2*PERCPU_PAGE_SIZE)
580 #endif
581 
582 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
583 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
584 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
585 #define __HAVE_ARCH_PTE_SAME
586 #define __HAVE_ARCH_PGD_OFFSET_GATE
587 
588 
589 #if CONFIG_PGTABLE_LEVELS == 3
590 #include <asm-generic/pgtable-nopud.h>
591 #endif
592 #include <asm-generic/pgtable.h>
593 
594 #endif /* _ASM_IA64_PGTABLE_H */
595