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. */
196static inline long
197ia64_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)))
227extern 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
328extern void __ia64_sync_icache_dcache(pte_t pteval);
329static 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
355struct file;
356extern 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
360static inline unsigned long
361pgd_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.  */
371static inline pgd_t*
372pgd_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
408static inline int
409ptep_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
424static inline pte_t
425ptep_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
436static inline void
437ptep_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
452static inline int
453pte_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
460extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
461extern 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 */
485extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
486extern 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