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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_IA64_PGTABLE_H
3#define _ASM_IA64_PGTABLE_H
4
5/*
6 * This file contains the functions and defines necessary to modify and use
7 * the IA-64 page table tree.
8 *
9 * This hopefully works with any (fixed) IA-64 page-size, as defined
10 * in <asm/page.h>.
11 *
12 * Copyright (C) 1998-2005 Hewlett-Packard Co
13 * David Mosberger-Tang <davidm@hpl.hp.com>
14 */
15
16
17#include <asm/mman.h>
18#include <asm/page.h>
19#include <asm/processor.h>
20#include <asm/types.h>
21
22#define IA64_MAX_PHYS_BITS 50 /* max. number of physical address bits (architected) */
23
24/*
25 * First, define the various bits in a PTE. Note that the PTE format
26 * matches the VHPT short format, the firt doubleword of the VHPD long
27 * format, and the first doubleword of the TLB insertion format.
28 */
29#define _PAGE_P_BIT 0
30#define _PAGE_A_BIT 5
31#define _PAGE_D_BIT 6
32
33#define _PAGE_P (1 << _PAGE_P_BIT) /* page present bit */
34#define _PAGE_MA_WB (0x0 << 2) /* write back memory attribute */
35#define _PAGE_MA_UC (0x4 << 2) /* uncacheable memory attribute */
36#define _PAGE_MA_UCE (0x5 << 2) /* UC exported attribute */
37#define _PAGE_MA_WC (0x6 << 2) /* write coalescing memory attribute */
38#define _PAGE_MA_NAT (0x7 << 2) /* not-a-thing attribute */
39#define _PAGE_MA_MASK (0x7 << 2)
40#define _PAGE_PL_0 (0 << 7) /* privilege level 0 (kernel) */
41#define _PAGE_PL_1 (1 << 7) /* privilege level 1 (unused) */
42#define _PAGE_PL_2 (2 << 7) /* privilege level 2 (unused) */
43#define _PAGE_PL_3 (3 << 7) /* privilege level 3 (user) */
44#define _PAGE_PL_MASK (3 << 7)
45#define _PAGE_AR_R (0 << 9) /* read only */
46#define _PAGE_AR_RX (1 << 9) /* read & execute */
47#define _PAGE_AR_RW (2 << 9) /* read & write */
48#define _PAGE_AR_RWX (3 << 9) /* read, write & execute */
49#define _PAGE_AR_R_RW (4 << 9) /* read / read & write */
50#define _PAGE_AR_RX_RWX (5 << 9) /* read & exec / read, write & exec */
51#define _PAGE_AR_RWX_RW (6 << 9) /* read, write & exec / read & write */
52#define _PAGE_AR_X_RX (7 << 9) /* exec & promote / read & exec */
53#define _PAGE_AR_MASK (7 << 9)
54#define _PAGE_AR_SHIFT 9
55#define _PAGE_A (1 << _PAGE_A_BIT) /* page accessed bit */
56#define _PAGE_D (1 << _PAGE_D_BIT) /* page dirty bit */
57#define _PAGE_PPN_MASK (((__IA64_UL(1) << IA64_MAX_PHYS_BITS) - 1) & ~0xfffUL)
58#define _PAGE_ED (__IA64_UL(1) << 52) /* exception deferral */
59#define _PAGE_PROTNONE (__IA64_UL(1) << 63)
60
61#define _PFN_MASK _PAGE_PPN_MASK
62/* Mask of bits which may be changed by pte_modify(); the odd bits are there for _PAGE_PROTNONE */
63#define _PAGE_CHG_MASK (_PAGE_P | _PAGE_PROTNONE | _PAGE_PL_MASK | _PAGE_AR_MASK | _PAGE_ED)
64
65#define _PAGE_SIZE_4K 12
66#define _PAGE_SIZE_8K 13
67#define _PAGE_SIZE_16K 14
68#define _PAGE_SIZE_64K 16
69#define _PAGE_SIZE_256K 18
70#define _PAGE_SIZE_1M 20
71#define _PAGE_SIZE_4M 22
72#define _PAGE_SIZE_16M 24
73#define _PAGE_SIZE_64M 26
74#define _PAGE_SIZE_256M 28
75#define _PAGE_SIZE_1G 30
76#define _PAGE_SIZE_4G 32
77
78#define __ACCESS_BITS _PAGE_ED | _PAGE_A | _PAGE_P | _PAGE_MA_WB
79#define __DIRTY_BITS_NO_ED _PAGE_A | _PAGE_P | _PAGE_D | _PAGE_MA_WB
80#define __DIRTY_BITS _PAGE_ED | __DIRTY_BITS_NO_ED
81
82/*
83 * How many pointers will a page table level hold expressed in shift
84 */
85#define PTRS_PER_PTD_SHIFT (PAGE_SHIFT-3)
86
87/*
88 * Definitions for fourth level:
89 */
90#define PTRS_PER_PTE (__IA64_UL(1) << (PTRS_PER_PTD_SHIFT))
91
92/*
93 * Definitions for third level:
94 *
95 * PMD_SHIFT determines the size of the area a third-level page table
96 * can map.
97 */
98#define PMD_SHIFT (PAGE_SHIFT + (PTRS_PER_PTD_SHIFT))
99#define PMD_SIZE (1UL << PMD_SHIFT)
100#define PMD_MASK (~(PMD_SIZE-1))
101#define PTRS_PER_PMD (1UL << (PTRS_PER_PTD_SHIFT))
102
103#if CONFIG_PGTABLE_LEVELS == 4
104/*
105 * Definitions for second level:
106 *
107 * PUD_SHIFT determines the size of the area a second-level page table
108 * can map.
109 */
110#define PUD_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
111#define PUD_SIZE (1UL << PUD_SHIFT)
112#define PUD_MASK (~(PUD_SIZE-1))
113#define PTRS_PER_PUD (1UL << (PTRS_PER_PTD_SHIFT))
114#endif
115
116/*
117 * Definitions for first level:
118 *
119 * PGDIR_SHIFT determines what a first-level page table entry can map.
120 */
121#if CONFIG_PGTABLE_LEVELS == 4
122#define PGDIR_SHIFT (PUD_SHIFT + (PTRS_PER_PTD_SHIFT))
123#else
124#define PGDIR_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
125#endif
126#define PGDIR_SIZE (__IA64_UL(1) << PGDIR_SHIFT)
127#define PGDIR_MASK (~(PGDIR_SIZE-1))
128#define PTRS_PER_PGD_SHIFT PTRS_PER_PTD_SHIFT
129#define PTRS_PER_PGD (1UL << PTRS_PER_PGD_SHIFT)
130#define USER_PTRS_PER_PGD (5*PTRS_PER_PGD/8) /* regions 0-4 are user regions */
131#define FIRST_USER_ADDRESS 0UL
132
133/*
134 * All the normal masks have the "page accessed" bits on, as any time
135 * they are used, the page is accessed. They are cleared only by the
136 * page-out routines.
137 */
138#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_A)
139#define PAGE_SHARED __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RW)
140#define PAGE_READONLY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
141#define PAGE_COPY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
142#define PAGE_COPY_EXEC __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
143#define PAGE_GATE __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_X_RX)
144#define PAGE_KERNEL __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX)
145#define PAGE_KERNELRX __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_RX)
146#define PAGE_KERNEL_UC __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX | \
147 _PAGE_MA_UC)
148
149# ifndef __ASSEMBLY__
150
151#include <linux/sched/mm.h> /* for mm_struct */
152#include <linux/bitops.h>
153#include <asm/cacheflush.h>
154#include <asm/mmu_context.h>
155
156/*
157 * Next come the mappings that determine how mmap() protection bits
158 * (PROT_EXEC, PROT_READ, PROT_WRITE, PROT_NONE) get implemented. The
159 * _P version gets used for a private shared memory segment, the _S
160 * version gets used for a shared memory segment with MAP_SHARED on.
161 * In a private shared memory segment, we do a copy-on-write if a task
162 * attempts to write to the page.
163 */
164 /* xwr */
165#define __P000 PAGE_NONE
166#define __P001 PAGE_READONLY
167#define __P010 PAGE_READONLY /* write to priv pg -> copy & make writable */
168#define __P011 PAGE_READONLY /* ditto */
169#define __P100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
170#define __P101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
171#define __P110 PAGE_COPY_EXEC
172#define __P111 PAGE_COPY_EXEC
173
174#define __S000 PAGE_NONE
175#define __S001 PAGE_READONLY
176#define __S010 PAGE_SHARED /* we don't have (and don't need) write-only */
177#define __S011 PAGE_SHARED
178#define __S100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
179#define __S101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
180#define __S110 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
181#define __S111 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
182
183#define pgd_ERROR(e) printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
184#if CONFIG_PGTABLE_LEVELS == 4
185#define pud_ERROR(e) printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
186#endif
187#define pmd_ERROR(e) printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
188#define pte_ERROR(e) printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
189
190
191/*
192 * Some definitions to translate between mem_map, PTEs, and page addresses:
193 */
194
195
196/* Quick test to see if ADDR is a (potentially) valid physical address. */
197static inline long
198ia64_phys_addr_valid (unsigned long addr)
199{
200 return (addr & (local_cpu_data->unimpl_pa_mask)) == 0;
201}
202
203/*
204 * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
205 * memory. For the return value to be meaningful, ADDR must be >=
206 * PAGE_OFFSET. This operation can be relatively expensive (e.g.,
207 * require a hash-, or multi-level tree-lookup or something of that
208 * sort) but it guarantees to return TRUE only if accessing the page
209 * at that address does not cause an error. Note that there may be
210 * addresses for which kern_addr_valid() returns FALSE even though an
211 * access would not cause an error (e.g., this is typically true for
212 * memory mapped I/O regions.
213 *
214 * XXX Need to implement this for IA-64.
215 */
216#define kern_addr_valid(addr) (1)
217
218
219/*
220 * Now come the defines and routines to manage and access the three-level
221 * page table.
222 */
223
224
225#define VMALLOC_START (RGN_BASE(RGN_GATE) + 0x200000000UL)
226#ifdef CONFIG_VIRTUAL_MEM_MAP
227# define VMALLOC_END_INIT (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
228extern unsigned long VMALLOC_END;
229#else
230#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP)
231/* SPARSEMEM_VMEMMAP uses half of vmalloc... */
232# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10)))
233# define vmemmap ((struct page *)VMALLOC_END)
234#else
235# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
236#endif
237#endif
238
239/* fs/proc/kcore.c */
240#define kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE))
241#define kc_offset_to_vaddr(o) ((o) + RGN_BASE(RGN_GATE))
242
243#define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3)
244#define RGN_MAP_LIMIT ((1UL << RGN_MAP_SHIFT) - PAGE_SIZE) /* per region addr limit */
245
246/*
247 * Conversion functions: convert page frame number (pfn) and a protection value to a page
248 * table entry (pte).
249 */
250#define pfn_pte(pfn, pgprot) \
251({ pte_t __pte; pte_val(__pte) = ((pfn) << PAGE_SHIFT) | pgprot_val(pgprot); __pte; })
252
253/* Extract pfn from pte. */
254#define pte_pfn(_pte) ((pte_val(_pte) & _PFN_MASK) >> PAGE_SHIFT)
255
256#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
257
258/* This takes a physical page address that is used by the remapping functions */
259#define mk_pte_phys(physpage, pgprot) \
260({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
261
262#define pte_modify(_pte, newprot) \
263 (__pte((pte_val(_pte) & ~_PAGE_CHG_MASK) | (pgprot_val(newprot) & _PAGE_CHG_MASK)))
264
265#define pte_none(pte) (!pte_val(pte))
266#define pte_present(pte) (pte_val(pte) & (_PAGE_P | _PAGE_PROTNONE))
267#define pte_clear(mm,addr,pte) (pte_val(*(pte)) = 0UL)
268/* pte_page() returns the "struct page *" corresponding to the PTE: */
269#define pte_page(pte) virt_to_page(((pte_val(pte) & _PFN_MASK) + PAGE_OFFSET))
270
271#define pmd_none(pmd) (!pmd_val(pmd))
272#define pmd_bad(pmd) (!ia64_phys_addr_valid(pmd_val(pmd)))
273#define pmd_present(pmd) (pmd_val(pmd) != 0UL)
274#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0UL)
275#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & _PFN_MASK))
276#define pmd_page(pmd) virt_to_page((pmd_val(pmd) + PAGE_OFFSET))
277
278#define pud_none(pud) (!pud_val(pud))
279#define pud_bad(pud) (!ia64_phys_addr_valid(pud_val(pud)))
280#define pud_present(pud) (pud_val(pud) != 0UL)
281#define pud_clear(pudp) (pud_val(*(pudp)) = 0UL)
282#define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & _PFN_MASK))
283#define pud_page(pud) virt_to_page((pud_val(pud) + PAGE_OFFSET))
284
285#if CONFIG_PGTABLE_LEVELS == 4
286#define p4d_none(p4d) (!p4d_val(p4d))
287#define p4d_bad(p4d) (!ia64_phys_addr_valid(p4d_val(p4d)))
288#define p4d_present(p4d) (p4d_val(p4d) != 0UL)
289#define p4d_clear(p4dp) (p4d_val(*(p4dp)) = 0UL)
290#define p4d_page_vaddr(p4d) ((unsigned long) __va(p4d_val(p4d) & _PFN_MASK))
291#define p4d_page(p4d) virt_to_page((p4d_val(p4d) + PAGE_OFFSET))
292#endif
293
294/*
295 * The following have defined behavior only work if pte_present() is true.
296 */
297#define pte_write(pte) ((unsigned) (((pte_val(pte) & _PAGE_AR_MASK) >> _PAGE_AR_SHIFT) - 2) <= 4)
298#define pte_exec(pte) ((pte_val(pte) & _PAGE_AR_RX) != 0)
299#define pte_dirty(pte) ((pte_val(pte) & _PAGE_D) != 0)
300#define pte_young(pte) ((pte_val(pte) & _PAGE_A) != 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
314/*
315 * Because ia64's Icache and Dcache is not coherent (on a cpu), we need to
316 * sync icache and dcache when we insert *new* executable page.
317 * __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache
318 * if necessary.
319 *
320 * set_pte() is also called by the kernel, but we can expect that the kernel
321 * flushes icache explicitly if necessary.
322 */
323#define pte_present_exec_user(pte)\
324 ((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \
325 (_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX))
326
327extern void __ia64_sync_icache_dcache(pte_t pteval);
328static inline void set_pte(pte_t *ptep, pte_t pteval)
329{
330 /* page is present && page is user && page is executable
331 * && (page swapin or new page or page migraton
332 * || copy_on_write with page copying.)
333 */
334 if (pte_present_exec_user(pteval) &&
335 (!pte_present(*ptep) ||
336 pte_pfn(*ptep) != pte_pfn(pteval)))
337 /* load_module() calles flush_icache_range() explicitly*/
338 __ia64_sync_icache_dcache(pteval);
339 *ptep = pteval;
340}
341
342#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
343
344/*
345 * Make page protection values cacheable, uncacheable, or write-
346 * combining. Note that "protection" is really a misnomer here as the
347 * protection value contains the memory attribute bits, dirty bits, and
348 * various other bits as well.
349 */
350#define pgprot_cacheable(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WB)
351#define pgprot_noncached(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_UC)
352#define pgprot_writecombine(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WC)
353
354struct file;
355extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
356 unsigned long size, pgprot_t vma_prot);
357#define __HAVE_PHYS_MEM_ACCESS_PROT
358
359static inline unsigned long
360pgd_index (unsigned long address)
361{
362 unsigned long region = address >> 61;
363 unsigned long l1index = (address >> PGDIR_SHIFT) & ((PTRS_PER_PGD >> 3) - 1);
364
365 return (region << (PAGE_SHIFT - 6)) | l1index;
366}
367#define pgd_index pgd_index
368
369/*
370 * In the kernel's mapped region we know everything is in region number 5, so
371 * as an optimisation its PGD already points to the area for that region.
372 * However, this also means that we cannot use pgd_index() and we must
373 * never add the region here.
374 */
375#define pgd_offset_k(addr) \
376 (init_mm.pgd + (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)))
377
378/* Look up a pgd entry in the gate area. On IA-64, the gate-area
379 resides in the kernel-mapped segment, hence we use pgd_offset_k()
380 here. */
381#define pgd_offset_gate(mm, addr) pgd_offset_k(addr)
382
383/* atomic versions of the some PTE manipulations: */
384
385static inline int
386ptep_test_and_clear_young (struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
387{
388#ifdef CONFIG_SMP
389 if (!pte_young(*ptep))
390 return 0;
391 return test_and_clear_bit(_PAGE_A_BIT, ptep);
392#else
393 pte_t pte = *ptep;
394 if (!pte_young(pte))
395 return 0;
396 set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
397 return 1;
398#endif
399}
400
401static inline pte_t
402ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
403{
404#ifdef CONFIG_SMP
405 return __pte(xchg((long *) ptep, 0));
406#else
407 pte_t pte = *ptep;
408 pte_clear(mm, addr, ptep);
409 return pte;
410#endif
411}
412
413static inline void
414ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
415{
416#ifdef CONFIG_SMP
417 unsigned long new, old;
418
419 do {
420 old = pte_val(*ptep);
421 new = pte_val(pte_wrprotect(__pte (old)));
422 } while (cmpxchg((unsigned long *) ptep, old, new) != old);
423#else
424 pte_t old_pte = *ptep;
425 set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
426#endif
427}
428
429static inline int
430pte_same (pte_t a, pte_t b)
431{
432 return pte_val(a) == pte_val(b);
433}
434
435#define update_mmu_cache(vma, address, ptep) do { } while (0)
436
437extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
438extern void paging_init (void);
439
440/*
441 * Note: The macros below rely on the fact that MAX_SWAPFILES_SHIFT <= number of
442 * bits in the swap-type field of the swap pte. It would be nice to
443 * enforce that, but we can't easily include <linux/swap.h> here.
444 * (Of course, better still would be to define MAX_SWAPFILES_SHIFT here...).
445 *
446 * Format of swap pte:
447 * bit 0 : present bit (must be zero)
448 * bits 1- 7: swap-type
449 * bits 8-62: swap offset
450 * bit 63 : _PAGE_PROTNONE bit
451 */
452#define __swp_type(entry) (((entry).val >> 1) & 0x7f)
453#define __swp_offset(entry) (((entry).val << 1) >> 9)
454#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 1) | ((long) (offset) << 8) })
455#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
456#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
457
458/*
459 * ZERO_PAGE is a global shared page that is always zero: used
460 * for zero-mapped memory areas etc..
461 */
462extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
463extern struct page *zero_page_memmap_ptr;
464#define ZERO_PAGE(vaddr) (zero_page_memmap_ptr)
465
466/* We provide our own get_unmapped_area to cope with VA holes for userland */
467#define HAVE_ARCH_UNMAPPED_AREA
468
469#ifdef CONFIG_HUGETLB_PAGE
470#define HUGETLB_PGDIR_SHIFT (HPAGE_SHIFT + 2*(PAGE_SHIFT-3))
471#define HUGETLB_PGDIR_SIZE (__IA64_UL(1) << HUGETLB_PGDIR_SHIFT)
472#define HUGETLB_PGDIR_MASK (~(HUGETLB_PGDIR_SIZE-1))
473#endif
474
475
476#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
477/*
478 * Update PTEP with ENTRY, which is guaranteed to be a less
479 * restrictive PTE. That is, ENTRY may have the ACCESSED, DIRTY, and
480 * WRITABLE bits turned on, when the value at PTEP did not. The
481 * WRITABLE bit may only be turned if SAFELY_WRITABLE is TRUE.
482 *
483 * SAFELY_WRITABLE is TRUE if we can update the value at PTEP without
484 * having to worry about races. On SMP machines, there are only two
485 * cases where this is true:
486 *
487 * (1) *PTEP has the PRESENT bit turned OFF
488 * (2) ENTRY has the DIRTY bit turned ON
489 *
490 * On ia64, we could implement this routine with a cmpxchg()-loop
491 * which ORs in the _PAGE_A/_PAGE_D bit if they're set in ENTRY.
492 * However, like on x86, we can get a more streamlined version by
493 * observing that it is OK to drop ACCESSED bit updates when
494 * SAFELY_WRITABLE is FALSE. Besides being rare, all that would do is
495 * result in an extra Access-bit fault, which would then turn on the
496 * ACCESSED bit in the low-level fault handler (iaccess_bit or
497 * daccess_bit in ivt.S).
498 */
499#ifdef CONFIG_SMP
500# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
501({ \
502 int __changed = !pte_same(*(__ptep), __entry); \
503 if (__changed && __safely_writable) { \
504 set_pte(__ptep, __entry); \
505 flush_tlb_page(__vma, __addr); \
506 } \
507 __changed; \
508})
509#else
510# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
511({ \
512 int __changed = !pte_same(*(__ptep), __entry); \
513 if (__changed) { \
514 set_pte_at((__vma)->vm_mm, (__addr), __ptep, __entry); \
515 flush_tlb_page(__vma, __addr); \
516 } \
517 __changed; \
518})
519#endif
520
521# ifdef CONFIG_VIRTUAL_MEM_MAP
522 /* arch mem_map init routine is needed due to holes in a virtual mem_map */
523 extern void memmap_init (unsigned long size, int nid, unsigned long zone,
524 unsigned long start_pfn);
525# endif /* CONFIG_VIRTUAL_MEM_MAP */
526# endif /* !__ASSEMBLY__ */
527
528/*
529 * Identity-mapped regions use a large page size. We'll call such large pages
530 * "granules". If you can think of a better name that's unambiguous, let me
531 * know...
532 */
533#if defined(CONFIG_IA64_GRANULE_64MB)
534# define IA64_GRANULE_SHIFT _PAGE_SIZE_64M
535#elif defined(CONFIG_IA64_GRANULE_16MB)
536# define IA64_GRANULE_SHIFT _PAGE_SIZE_16M
537#endif
538#define IA64_GRANULE_SIZE (1 << IA64_GRANULE_SHIFT)
539/*
540 * log2() of the page size we use to map the kernel image (IA64_TR_KERNEL):
541 */
542#define KERNEL_TR_PAGE_SHIFT _PAGE_SIZE_64M
543#define KERNEL_TR_PAGE_SIZE (1 << KERNEL_TR_PAGE_SHIFT)
544
545/* These tell get_user_pages() that the first gate page is accessible from user-level. */
546#define FIXADDR_USER_START GATE_ADDR
547#ifdef HAVE_BUGGY_SEGREL
548# define FIXADDR_USER_END (GATE_ADDR + 2*PAGE_SIZE)
549#else
550# define FIXADDR_USER_END (GATE_ADDR + 2*PERCPU_PAGE_SIZE)
551#endif
552
553#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
554#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
555#define __HAVE_ARCH_PTEP_SET_WRPROTECT
556#define __HAVE_ARCH_PTE_SAME
557#define __HAVE_ARCH_PGD_OFFSET_GATE
558
559
560#if CONFIG_PGTABLE_LEVELS == 3
561#include <asm-generic/pgtable-nopud.h>
562#endif
563#include <asm-generic/pgtable-nop4d.h>
564
565#endif /* _ASM_IA64_PGTABLE_H */
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_IA64_PGTABLE_H
3#define _ASM_IA64_PGTABLE_H
4
5/*
6 * This file contains the functions and defines necessary to modify and use
7 * the IA-64 page table tree.
8 *
9 * This hopefully works with any (fixed) IA-64 page-size, as defined
10 * in <asm/page.h>.
11 *
12 * Copyright (C) 1998-2005 Hewlett-Packard Co
13 * David Mosberger-Tang <davidm@hpl.hp.com>
14 */
15
16
17#include <asm/mman.h>
18#include <asm/page.h>
19#include <asm/processor.h>
20#include <asm/types.h>
21
22#define IA64_MAX_PHYS_BITS 50 /* max. number of physical address bits (architected) */
23
24/*
25 * First, define the various bits in a PTE. Note that the PTE format
26 * matches the VHPT short format, the firt doubleword of the VHPD long
27 * format, and the first doubleword of the TLB insertion format.
28 */
29#define _PAGE_P_BIT 0
30#define _PAGE_A_BIT 5
31#define _PAGE_D_BIT 6
32
33#define _PAGE_P (1 << _PAGE_P_BIT) /* page present bit */
34#define _PAGE_MA_WB (0x0 << 2) /* write back memory attribute */
35#define _PAGE_MA_UC (0x4 << 2) /* uncacheable memory attribute */
36#define _PAGE_MA_UCE (0x5 << 2) /* UC exported attribute */
37#define _PAGE_MA_WC (0x6 << 2) /* write coalescing memory attribute */
38#define _PAGE_MA_NAT (0x7 << 2) /* not-a-thing attribute */
39#define _PAGE_MA_MASK (0x7 << 2)
40#define _PAGE_PL_0 (0 << 7) /* privilege level 0 (kernel) */
41#define _PAGE_PL_1 (1 << 7) /* privilege level 1 (unused) */
42#define _PAGE_PL_2 (2 << 7) /* privilege level 2 (unused) */
43#define _PAGE_PL_3 (3 << 7) /* privilege level 3 (user) */
44#define _PAGE_PL_MASK (3 << 7)
45#define _PAGE_AR_R (0 << 9) /* read only */
46#define _PAGE_AR_RX (1 << 9) /* read & execute */
47#define _PAGE_AR_RW (2 << 9) /* read & write */
48#define _PAGE_AR_RWX (3 << 9) /* read, write & execute */
49#define _PAGE_AR_R_RW (4 << 9) /* read / read & write */
50#define _PAGE_AR_RX_RWX (5 << 9) /* read & exec / read, write & exec */
51#define _PAGE_AR_RWX_RW (6 << 9) /* read, write & exec / read & write */
52#define _PAGE_AR_X_RX (7 << 9) /* exec & promote / read & exec */
53#define _PAGE_AR_MASK (7 << 9)
54#define _PAGE_AR_SHIFT 9
55#define _PAGE_A (1 << _PAGE_A_BIT) /* page accessed bit */
56#define _PAGE_D (1 << _PAGE_D_BIT) /* page dirty bit */
57#define _PAGE_PPN_MASK (((__IA64_UL(1) << IA64_MAX_PHYS_BITS) - 1) & ~0xfffUL)
58#define _PAGE_ED (__IA64_UL(1) << 52) /* exception deferral */
59#define _PAGE_PROTNONE (__IA64_UL(1) << 63)
60
61#define _PFN_MASK _PAGE_PPN_MASK
62/* Mask of bits which may be changed by pte_modify(); the odd bits are there for _PAGE_PROTNONE */
63#define _PAGE_CHG_MASK (_PAGE_P | _PAGE_PROTNONE | _PAGE_PL_MASK | _PAGE_AR_MASK | _PAGE_ED)
64
65#define _PAGE_SIZE_4K 12
66#define _PAGE_SIZE_8K 13
67#define _PAGE_SIZE_16K 14
68#define _PAGE_SIZE_64K 16
69#define _PAGE_SIZE_256K 18
70#define _PAGE_SIZE_1M 20
71#define _PAGE_SIZE_4M 22
72#define _PAGE_SIZE_16M 24
73#define _PAGE_SIZE_64M 26
74#define _PAGE_SIZE_256M 28
75#define _PAGE_SIZE_1G 30
76#define _PAGE_SIZE_4G 32
77
78#define __ACCESS_BITS _PAGE_ED | _PAGE_A | _PAGE_P | _PAGE_MA_WB
79#define __DIRTY_BITS_NO_ED _PAGE_A | _PAGE_P | _PAGE_D | _PAGE_MA_WB
80#define __DIRTY_BITS _PAGE_ED | __DIRTY_BITS_NO_ED
81
82/*
83 * How many pointers will a page table level hold expressed in shift
84 */
85#define PTRS_PER_PTD_SHIFT (PAGE_SHIFT-3)
86
87/*
88 * Definitions for fourth level:
89 */
90#define PTRS_PER_PTE (__IA64_UL(1) << (PTRS_PER_PTD_SHIFT))
91
92/*
93 * Definitions for third level:
94 *
95 * PMD_SHIFT determines the size of the area a third-level page table
96 * can map.
97 */
98#define PMD_SHIFT (PAGE_SHIFT + (PTRS_PER_PTD_SHIFT))
99#define PMD_SIZE (1UL << PMD_SHIFT)
100#define PMD_MASK (~(PMD_SIZE-1))
101#define PTRS_PER_PMD (1UL << (PTRS_PER_PTD_SHIFT))
102
103#if CONFIG_PGTABLE_LEVELS == 4
104/*
105 * Definitions for second level:
106 *
107 * PUD_SHIFT determines the size of the area a second-level page table
108 * can map.
109 */
110#define PUD_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
111#define PUD_SIZE (1UL << PUD_SHIFT)
112#define PUD_MASK (~(PUD_SIZE-1))
113#define PTRS_PER_PUD (1UL << (PTRS_PER_PTD_SHIFT))
114#endif
115
116/*
117 * Definitions for first level:
118 *
119 * PGDIR_SHIFT determines what a first-level page table entry can map.
120 */
121#if CONFIG_PGTABLE_LEVELS == 4
122#define PGDIR_SHIFT (PUD_SHIFT + (PTRS_PER_PTD_SHIFT))
123#else
124#define PGDIR_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
125#endif
126#define PGDIR_SIZE (__IA64_UL(1) << PGDIR_SHIFT)
127#define PGDIR_MASK (~(PGDIR_SIZE-1))
128#define PTRS_PER_PGD_SHIFT PTRS_PER_PTD_SHIFT
129#define PTRS_PER_PGD (1UL << PTRS_PER_PGD_SHIFT)
130#define USER_PTRS_PER_PGD (5*PTRS_PER_PGD/8) /* regions 0-4 are user regions */
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/mm.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 pgd_ERROR(e) printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
165#if CONFIG_PGTABLE_LEVELS == 4
166#define pud_ERROR(e) printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
167#endif
168#define pmd_ERROR(e) printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
169#define pte_ERROR(e) printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
170
171
172/*
173 * Some definitions to translate between mem_map, PTEs, and page addresses:
174 */
175
176
177/* Quick test to see if ADDR is a (potentially) valid physical address. */
178static inline long
179ia64_phys_addr_valid (unsigned long addr)
180{
181 return (addr & (local_cpu_data->unimpl_pa_mask)) == 0;
182}
183
184/*
185 * Now come the defines and routines to manage and access the three-level
186 * page table.
187 */
188
189
190#define VMALLOC_START (RGN_BASE(RGN_GATE) + 0x200000000UL)
191#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP)
192/* SPARSEMEM_VMEMMAP uses half of vmalloc... */
193# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10)))
194# define vmemmap ((struct page *)VMALLOC_END)
195#else
196# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
197#endif
198
199/* fs/proc/kcore.c */
200#define kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE))
201#define kc_offset_to_vaddr(o) ((o) + RGN_BASE(RGN_GATE))
202
203#define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3)
204#define RGN_MAP_LIMIT ((1UL << RGN_MAP_SHIFT) - PAGE_SIZE) /* per region addr limit */
205
206/*
207 * Conversion functions: convert page frame number (pfn) and a protection value to a page
208 * table entry (pte).
209 */
210#define pfn_pte(pfn, pgprot) \
211({ pte_t __pte; pte_val(__pte) = ((pfn) << PAGE_SHIFT) | pgprot_val(pgprot); __pte; })
212
213/* Extract pfn from pte. */
214#define pte_pfn(_pte) ((pte_val(_pte) & _PFN_MASK) >> PAGE_SHIFT)
215
216#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
217
218/* This takes a physical page address that is used by the remapping functions */
219#define mk_pte_phys(physpage, pgprot) \
220({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
221
222#define pte_modify(_pte, newprot) \
223 (__pte((pte_val(_pte) & ~_PAGE_CHG_MASK) | (pgprot_val(newprot) & _PAGE_CHG_MASK)))
224
225#define pte_none(pte) (!pte_val(pte))
226#define pte_present(pte) (pte_val(pte) & (_PAGE_P | _PAGE_PROTNONE))
227#define pte_clear(mm,addr,pte) (pte_val(*(pte)) = 0UL)
228/* pte_page() returns the "struct page *" corresponding to the PTE: */
229#define pte_page(pte) virt_to_page(((pte_val(pte) & _PFN_MASK) + PAGE_OFFSET))
230
231#define pmd_none(pmd) (!pmd_val(pmd))
232#define pmd_bad(pmd) (!ia64_phys_addr_valid(pmd_val(pmd)))
233#define pmd_present(pmd) (pmd_val(pmd) != 0UL)
234#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0UL)
235#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & _PFN_MASK))
236#define pmd_pfn(pmd) ((pmd_val(pmd) & _PFN_MASK) >> PAGE_SHIFT)
237#define pmd_page(pmd) virt_to_page((pmd_val(pmd) + PAGE_OFFSET))
238
239#define pud_none(pud) (!pud_val(pud))
240#define pud_bad(pud) (!ia64_phys_addr_valid(pud_val(pud)))
241#define pud_present(pud) (pud_val(pud) != 0UL)
242#define pud_clear(pudp) (pud_val(*(pudp)) = 0UL)
243#define pud_pgtable(pud) ((pmd_t *) __va(pud_val(pud) & _PFN_MASK))
244#define pud_page(pud) virt_to_page((pud_val(pud) + PAGE_OFFSET))
245
246#if CONFIG_PGTABLE_LEVELS == 4
247#define p4d_none(p4d) (!p4d_val(p4d))
248#define p4d_bad(p4d) (!ia64_phys_addr_valid(p4d_val(p4d)))
249#define p4d_present(p4d) (p4d_val(p4d) != 0UL)
250#define p4d_clear(p4dp) (p4d_val(*(p4dp)) = 0UL)
251#define p4d_pgtable(p4d) ((pud_t *) __va(p4d_val(p4d) & _PFN_MASK))
252#define p4d_page(p4d) virt_to_page((p4d_val(p4d) + PAGE_OFFSET))
253#endif
254
255/*
256 * The following have defined behavior only work if pte_present() is true.
257 */
258#define pte_write(pte) ((unsigned) (((pte_val(pte) & _PAGE_AR_MASK) >> _PAGE_AR_SHIFT) - 2) <= 4)
259#define pte_exec(pte) ((pte_val(pte) & _PAGE_AR_RX) != 0)
260#define pte_dirty(pte) ((pte_val(pte) & _PAGE_D) != 0)
261#define pte_young(pte) ((pte_val(pte) & _PAGE_A) != 0)
262
263/*
264 * Note: we convert AR_RWX to AR_RX and AR_RW to AR_R by clearing the 2nd bit in the
265 * access rights:
266 */
267#define pte_wrprotect(pte) (__pte(pte_val(pte) & ~_PAGE_AR_RW))
268#define pte_mkwrite(pte) (__pte(pte_val(pte) | _PAGE_AR_RW))
269#define pte_mkold(pte) (__pte(pte_val(pte) & ~_PAGE_A))
270#define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_A))
271#define pte_mkclean(pte) (__pte(pte_val(pte) & ~_PAGE_D))
272#define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D))
273#define pte_mkhuge(pte) (__pte(pte_val(pte)))
274
275/*
276 * Because ia64's Icache and Dcache is not coherent (on a cpu), we need to
277 * sync icache and dcache when we insert *new* executable page.
278 * __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache
279 * if necessary.
280 *
281 * set_pte() is also called by the kernel, but we can expect that the kernel
282 * flushes icache explicitly if necessary.
283 */
284#define pte_present_exec_user(pte)\
285 ((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \
286 (_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX))
287
288extern void __ia64_sync_icache_dcache(pte_t pteval);
289static inline void set_pte(pte_t *ptep, pte_t pteval)
290{
291 /* page is present && page is user && page is executable
292 * && (page swapin or new page or page migration
293 * || copy_on_write with page copying.)
294 */
295 if (pte_present_exec_user(pteval) &&
296 (!pte_present(*ptep) ||
297 pte_pfn(*ptep) != pte_pfn(pteval)))
298 /* load_module() calles flush_icache_range() explicitly*/
299 __ia64_sync_icache_dcache(pteval);
300 *ptep = pteval;
301}
302
303#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
304
305/*
306 * Make page protection values cacheable, uncacheable, or write-
307 * combining. Note that "protection" is really a misnomer here as the
308 * protection value contains the memory attribute bits, dirty bits, and
309 * various other bits as well.
310 */
311#define pgprot_cacheable(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WB)
312#define pgprot_noncached(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_UC)
313#define pgprot_writecombine(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WC)
314
315struct file;
316extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
317 unsigned long size, pgprot_t vma_prot);
318#define __HAVE_PHYS_MEM_ACCESS_PROT
319
320static inline unsigned long
321pgd_index (unsigned long address)
322{
323 unsigned long region = address >> 61;
324 unsigned long l1index = (address >> PGDIR_SHIFT) & ((PTRS_PER_PGD >> 3) - 1);
325
326 return (region << (PAGE_SHIFT - 6)) | l1index;
327}
328#define pgd_index pgd_index
329
330/*
331 * In the kernel's mapped region we know everything is in region number 5, so
332 * as an optimisation its PGD already points to the area for that region.
333 * However, this also means that we cannot use pgd_index() and we must
334 * never add the region here.
335 */
336#define pgd_offset_k(addr) \
337 (init_mm.pgd + (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)))
338
339/* Look up a pgd entry in the gate area. On IA-64, the gate-area
340 resides in the kernel-mapped segment, hence we use pgd_offset_k()
341 here. */
342#define pgd_offset_gate(mm, addr) pgd_offset_k(addr)
343
344/* atomic versions of the some PTE manipulations: */
345
346static inline int
347ptep_test_and_clear_young (struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
348{
349#ifdef CONFIG_SMP
350 if (!pte_young(*ptep))
351 return 0;
352 return test_and_clear_bit(_PAGE_A_BIT, ptep);
353#else
354 pte_t pte = *ptep;
355 if (!pte_young(pte))
356 return 0;
357 set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
358 return 1;
359#endif
360}
361
362static inline pte_t
363ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
364{
365#ifdef CONFIG_SMP
366 return __pte(xchg((long *) ptep, 0));
367#else
368 pte_t pte = *ptep;
369 pte_clear(mm, addr, ptep);
370 return pte;
371#endif
372}
373
374static inline void
375ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
376{
377#ifdef CONFIG_SMP
378 unsigned long new, old;
379
380 do {
381 old = pte_val(*ptep);
382 new = pte_val(pte_wrprotect(__pte (old)));
383 } while (cmpxchg((unsigned long *) ptep, old, new) != old);
384#else
385 pte_t old_pte = *ptep;
386 set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
387#endif
388}
389
390static inline int
391pte_same (pte_t a, pte_t b)
392{
393 return pte_val(a) == pte_val(b);
394}
395
396#define update_mmu_cache(vma, address, ptep) do { } while (0)
397
398extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
399extern void paging_init (void);
400
401/*
402 * Note: The macros below rely on the fact that MAX_SWAPFILES_SHIFT <= number of
403 * bits in the swap-type field of the swap pte. It would be nice to
404 * enforce that, but we can't easily include <linux/swap.h> here.
405 * (Of course, better still would be to define MAX_SWAPFILES_SHIFT here...).
406 *
407 * Format of swap pte:
408 * bit 0 : present bit (must be zero)
409 * bits 1- 7: swap-type
410 * bits 8-62: swap offset
411 * bit 63 : _PAGE_PROTNONE bit
412 */
413#define __swp_type(entry) (((entry).val >> 1) & 0x7f)
414#define __swp_offset(entry) (((entry).val << 1) >> 9)
415#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 1) | ((long) (offset) << 8) })
416#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
417#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
418
419/*
420 * ZERO_PAGE is a global shared page that is always zero: used
421 * for zero-mapped memory areas etc..
422 */
423extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
424extern struct page *zero_page_memmap_ptr;
425#define ZERO_PAGE(vaddr) (zero_page_memmap_ptr)
426
427/* We provide our own get_unmapped_area to cope with VA holes for userland */
428#define HAVE_ARCH_UNMAPPED_AREA
429
430#ifdef CONFIG_HUGETLB_PAGE
431#define HUGETLB_PGDIR_SHIFT (HPAGE_SHIFT + 2*(PAGE_SHIFT-3))
432#define HUGETLB_PGDIR_SIZE (__IA64_UL(1) << HUGETLB_PGDIR_SHIFT)
433#define HUGETLB_PGDIR_MASK (~(HUGETLB_PGDIR_SIZE-1))
434#endif
435
436
437#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
438/*
439 * Update PTEP with ENTRY, which is guaranteed to be a less
440 * restrictive PTE. That is, ENTRY may have the ACCESSED, DIRTY, and
441 * WRITABLE bits turned on, when the value at PTEP did not. The
442 * WRITABLE bit may only be turned if SAFELY_WRITABLE is TRUE.
443 *
444 * SAFELY_WRITABLE is TRUE if we can update the value at PTEP without
445 * having to worry about races. On SMP machines, there are only two
446 * cases where this is true:
447 *
448 * (1) *PTEP has the PRESENT bit turned OFF
449 * (2) ENTRY has the DIRTY bit turned ON
450 *
451 * On ia64, we could implement this routine with a cmpxchg()-loop
452 * which ORs in the _PAGE_A/_PAGE_D bit if they're set in ENTRY.
453 * However, like on x86, we can get a more streamlined version by
454 * observing that it is OK to drop ACCESSED bit updates when
455 * SAFELY_WRITABLE is FALSE. Besides being rare, all that would do is
456 * result in an extra Access-bit fault, which would then turn on the
457 * ACCESSED bit in the low-level fault handler (iaccess_bit or
458 * daccess_bit in ivt.S).
459 */
460#ifdef CONFIG_SMP
461# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
462({ \
463 int __changed = !pte_same(*(__ptep), __entry); \
464 if (__changed && __safely_writable) { \
465 set_pte(__ptep, __entry); \
466 flush_tlb_page(__vma, __addr); \
467 } \
468 __changed; \
469})
470#else
471# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
472({ \
473 int __changed = !pte_same(*(__ptep), __entry); \
474 if (__changed) { \
475 set_pte_at((__vma)->vm_mm, (__addr), __ptep, __entry); \
476 flush_tlb_page(__vma, __addr); \
477 } \
478 __changed; \
479})
480#endif
481# endif /* !__ASSEMBLY__ */
482
483/*
484 * Identity-mapped regions use a large page size. We'll call such large pages
485 * "granules". If you can think of a better name that's unambiguous, let me
486 * know...
487 */
488#if defined(CONFIG_IA64_GRANULE_64MB)
489# define IA64_GRANULE_SHIFT _PAGE_SIZE_64M
490#elif defined(CONFIG_IA64_GRANULE_16MB)
491# define IA64_GRANULE_SHIFT _PAGE_SIZE_16M
492#endif
493#define IA64_GRANULE_SIZE (1 << IA64_GRANULE_SHIFT)
494/*
495 * log2() of the page size we use to map the kernel image (IA64_TR_KERNEL):
496 */
497#define KERNEL_TR_PAGE_SHIFT _PAGE_SIZE_64M
498#define KERNEL_TR_PAGE_SIZE (1 << KERNEL_TR_PAGE_SHIFT)
499
500/* These tell get_user_pages() that the first gate page is accessible from user-level. */
501#define FIXADDR_USER_START GATE_ADDR
502#ifdef HAVE_BUGGY_SEGREL
503# define FIXADDR_USER_END (GATE_ADDR + 2*PAGE_SIZE)
504#else
505# define FIXADDR_USER_END (GATE_ADDR + 2*PERCPU_PAGE_SIZE)
506#endif
507
508#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
509#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
510#define __HAVE_ARCH_PTEP_SET_WRPROTECT
511#define __HAVE_ARCH_PTE_SAME
512#define __HAVE_ARCH_PGD_OFFSET_GATE
513
514
515#if CONFIG_PGTABLE_LEVELS == 3
516#include <asm-generic/pgtable-nopud.h>
517#endif
518#include <asm-generic/pgtable-nop4d.h>
519
520#endif /* _ASM_IA64_PGTABLE_H */