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1#ifndef _ASM_GENERIC_PGTABLE_H
2#define _ASM_GENERIC_PGTABLE_H
3
4#ifndef __ASSEMBLY__
5#ifdef CONFIG_MMU
6
7#include <linux/mm_types.h>
8
9#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
10extern int ptep_set_access_flags(struct vm_area_struct *vma,
11 unsigned long address, pte_t *ptep,
12 pte_t entry, int dirty);
13#endif
14
15#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
16extern int pmdp_set_access_flags(struct vm_area_struct *vma,
17 unsigned long address, pmd_t *pmdp,
18 pmd_t entry, int dirty);
19#endif
20
21#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
22static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
23 unsigned long address,
24 pte_t *ptep)
25{
26 pte_t pte = *ptep;
27 int r = 1;
28 if (!pte_young(pte))
29 r = 0;
30 else
31 set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte));
32 return r;
33}
34#endif
35
36#ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
37#ifdef CONFIG_TRANSPARENT_HUGEPAGE
38static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
39 unsigned long address,
40 pmd_t *pmdp)
41{
42 pmd_t pmd = *pmdp;
43 int r = 1;
44 if (!pmd_young(pmd))
45 r = 0;
46 else
47 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
48 return r;
49}
50#else /* CONFIG_TRANSPARENT_HUGEPAGE */
51static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
52 unsigned long address,
53 pmd_t *pmdp)
54{
55 BUG();
56 return 0;
57}
58#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
59#endif
60
61#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
62int ptep_clear_flush_young(struct vm_area_struct *vma,
63 unsigned long address, pte_t *ptep);
64#endif
65
66#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
67int pmdp_clear_flush_young(struct vm_area_struct *vma,
68 unsigned long address, pmd_t *pmdp);
69#endif
70
71#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
72static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
73 unsigned long address,
74 pte_t *ptep)
75{
76 pte_t pte = *ptep;
77 pte_clear(mm, address, ptep);
78 return pte;
79}
80#endif
81
82#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR
83#ifdef CONFIG_TRANSPARENT_HUGEPAGE
84static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
85 unsigned long address,
86 pmd_t *pmdp)
87{
88 pmd_t pmd = *pmdp;
89 pmd_clear(mm, address, pmdp);
90 return pmd;
91}
92#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
93#endif
94
95#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
96static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
97 unsigned long address, pte_t *ptep,
98 int full)
99{
100 pte_t pte;
101 pte = ptep_get_and_clear(mm, address, ptep);
102 return pte;
103}
104#endif
105
106/*
107 * Some architectures may be able to avoid expensive synchronization
108 * primitives when modifications are made to PTE's which are already
109 * not present, or in the process of an address space destruction.
110 */
111#ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL
112static inline void pte_clear_not_present_full(struct mm_struct *mm,
113 unsigned long address,
114 pte_t *ptep,
115 int full)
116{
117 pte_clear(mm, address, ptep);
118}
119#endif
120
121#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
122extern pte_t ptep_clear_flush(struct vm_area_struct *vma,
123 unsigned long address,
124 pte_t *ptep);
125#endif
126
127#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
128extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
129 unsigned long address,
130 pmd_t *pmdp);
131#endif
132
133#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
134struct mm_struct;
135static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
136{
137 pte_t old_pte = *ptep;
138 set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
139}
140#endif
141
142#ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT
143#ifdef CONFIG_TRANSPARENT_HUGEPAGE
144static inline void pmdp_set_wrprotect(struct mm_struct *mm,
145 unsigned long address, pmd_t *pmdp)
146{
147 pmd_t old_pmd = *pmdp;
148 set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd));
149}
150#else /* CONFIG_TRANSPARENT_HUGEPAGE */
151static inline void pmdp_set_wrprotect(struct mm_struct *mm,
152 unsigned long address, pmd_t *pmdp)
153{
154 BUG();
155}
156#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
157#endif
158
159#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
160extern pmd_t pmdp_splitting_flush(struct vm_area_struct *vma,
161 unsigned long address,
162 pmd_t *pmdp);
163#endif
164
165#ifndef __HAVE_ARCH_PTE_SAME
166static inline int pte_same(pte_t pte_a, pte_t pte_b)
167{
168 return pte_val(pte_a) == pte_val(pte_b);
169}
170#endif
171
172#ifndef __HAVE_ARCH_PMD_SAME
173#ifdef CONFIG_TRANSPARENT_HUGEPAGE
174static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
175{
176 return pmd_val(pmd_a) == pmd_val(pmd_b);
177}
178#else /* CONFIG_TRANSPARENT_HUGEPAGE */
179static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
180{
181 BUG();
182 return 0;
183}
184#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
185#endif
186
187#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY
188#define page_test_and_clear_dirty(pfn, mapped) (0)
189#endif
190
191#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_DIRTY
192#define pte_maybe_dirty(pte) pte_dirty(pte)
193#else
194#define pte_maybe_dirty(pte) (1)
195#endif
196
197#ifndef __HAVE_ARCH_PAGE_TEST_AND_CLEAR_YOUNG
198#define page_test_and_clear_young(pfn) (0)
199#endif
200
201#ifndef __HAVE_ARCH_PGD_OFFSET_GATE
202#define pgd_offset_gate(mm, addr) pgd_offset(mm, addr)
203#endif
204
205#ifndef __HAVE_ARCH_MOVE_PTE
206#define move_pte(pte, prot, old_addr, new_addr) (pte)
207#endif
208
209#ifndef flush_tlb_fix_spurious_fault
210#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
211#endif
212
213#ifndef pgprot_noncached
214#define pgprot_noncached(prot) (prot)
215#endif
216
217#ifndef pgprot_writecombine
218#define pgprot_writecombine pgprot_noncached
219#endif
220
221/*
222 * When walking page tables, get the address of the next boundary,
223 * or the end address of the range if that comes earlier. Although no
224 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
225 */
226
227#define pgd_addr_end(addr, end) \
228({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \
229 (__boundary - 1 < (end) - 1)? __boundary: (end); \
230})
231
232#ifndef pud_addr_end
233#define pud_addr_end(addr, end) \
234({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \
235 (__boundary - 1 < (end) - 1)? __boundary: (end); \
236})
237#endif
238
239#ifndef pmd_addr_end
240#define pmd_addr_end(addr, end) \
241({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \
242 (__boundary - 1 < (end) - 1)? __boundary: (end); \
243})
244#endif
245
246/*
247 * When walking page tables, we usually want to skip any p?d_none entries;
248 * and any p?d_bad entries - reporting the error before resetting to none.
249 * Do the tests inline, but report and clear the bad entry in mm/memory.c.
250 */
251void pgd_clear_bad(pgd_t *);
252void pud_clear_bad(pud_t *);
253void pmd_clear_bad(pmd_t *);
254
255static inline int pgd_none_or_clear_bad(pgd_t *pgd)
256{
257 if (pgd_none(*pgd))
258 return 1;
259 if (unlikely(pgd_bad(*pgd))) {
260 pgd_clear_bad(pgd);
261 return 1;
262 }
263 return 0;
264}
265
266static inline int pud_none_or_clear_bad(pud_t *pud)
267{
268 if (pud_none(*pud))
269 return 1;
270 if (unlikely(pud_bad(*pud))) {
271 pud_clear_bad(pud);
272 return 1;
273 }
274 return 0;
275}
276
277static inline int pmd_none_or_clear_bad(pmd_t *pmd)
278{
279 if (pmd_none(*pmd))
280 return 1;
281 if (unlikely(pmd_bad(*pmd))) {
282 pmd_clear_bad(pmd);
283 return 1;
284 }
285 return 0;
286}
287
288static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm,
289 unsigned long addr,
290 pte_t *ptep)
291{
292 /*
293 * Get the current pte state, but zero it out to make it
294 * non-present, preventing the hardware from asynchronously
295 * updating it.
296 */
297 return ptep_get_and_clear(mm, addr, ptep);
298}
299
300static inline void __ptep_modify_prot_commit(struct mm_struct *mm,
301 unsigned long addr,
302 pte_t *ptep, pte_t pte)
303{
304 /*
305 * The pte is non-present, so there's no hardware state to
306 * preserve.
307 */
308 set_pte_at(mm, addr, ptep, pte);
309}
310
311#ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
312/*
313 * Start a pte protection read-modify-write transaction, which
314 * protects against asynchronous hardware modifications to the pte.
315 * The intention is not to prevent the hardware from making pte
316 * updates, but to prevent any updates it may make from being lost.
317 *
318 * This does not protect against other software modifications of the
319 * pte; the appropriate pte lock must be held over the transation.
320 *
321 * Note that this interface is intended to be batchable, meaning that
322 * ptep_modify_prot_commit may not actually update the pte, but merely
323 * queue the update to be done at some later time. The update must be
324 * actually committed before the pte lock is released, however.
325 */
326static inline pte_t ptep_modify_prot_start(struct mm_struct *mm,
327 unsigned long addr,
328 pte_t *ptep)
329{
330 return __ptep_modify_prot_start(mm, addr, ptep);
331}
332
333/*
334 * Commit an update to a pte, leaving any hardware-controlled bits in
335 * the PTE unmodified.
336 */
337static inline void ptep_modify_prot_commit(struct mm_struct *mm,
338 unsigned long addr,
339 pte_t *ptep, pte_t pte)
340{
341 __ptep_modify_prot_commit(mm, addr, ptep, pte);
342}
343#endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */
344#endif /* CONFIG_MMU */
345
346/*
347 * A facility to provide lazy MMU batching. This allows PTE updates and
348 * page invalidations to be delayed until a call to leave lazy MMU mode
349 * is issued. Some architectures may benefit from doing this, and it is
350 * beneficial for both shadow and direct mode hypervisors, which may batch
351 * the PTE updates which happen during this window. Note that using this
352 * interface requires that read hazards be removed from the code. A read
353 * hazard could result in the direct mode hypervisor case, since the actual
354 * write to the page tables may not yet have taken place, so reads though
355 * a raw PTE pointer after it has been modified are not guaranteed to be
356 * up to date. This mode can only be entered and left under the protection of
357 * the page table locks for all page tables which may be modified. In the UP
358 * case, this is required so that preemption is disabled, and in the SMP case,
359 * it must synchronize the delayed page table writes properly on other CPUs.
360 */
361#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
362#define arch_enter_lazy_mmu_mode() do {} while (0)
363#define arch_leave_lazy_mmu_mode() do {} while (0)
364#define arch_flush_lazy_mmu_mode() do {} while (0)
365#endif
366
367/*
368 * A facility to provide batching of the reload of page tables and
369 * other process state with the actual context switch code for
370 * paravirtualized guests. By convention, only one of the batched
371 * update (lazy) modes (CPU, MMU) should be active at any given time,
372 * entry should never be nested, and entry and exits should always be
373 * paired. This is for sanity of maintaining and reasoning about the
374 * kernel code. In this case, the exit (end of the context switch) is
375 * in architecture-specific code, and so doesn't need a generic
376 * definition.
377 */
378#ifndef __HAVE_ARCH_START_CONTEXT_SWITCH
379#define arch_start_context_switch(prev) do {} while (0)
380#endif
381
382#ifndef __HAVE_PFNMAP_TRACKING
383/*
384 * Interface that can be used by architecture code to keep track of
385 * memory type of pfn mappings (remap_pfn_range, vm_insert_pfn)
386 *
387 * track_pfn_vma_new is called when a _new_ pfn mapping is being established
388 * for physical range indicated by pfn and size.
389 */
390static inline int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
391 unsigned long pfn, unsigned long size)
392{
393 return 0;
394}
395
396/*
397 * Interface that can be used by architecture code to keep track of
398 * memory type of pfn mappings (remap_pfn_range, vm_insert_pfn)
399 *
400 * track_pfn_vma_copy is called when vma that is covering the pfnmap gets
401 * copied through copy_page_range().
402 */
403static inline int track_pfn_vma_copy(struct vm_area_struct *vma)
404{
405 return 0;
406}
407
408/*
409 * Interface that can be used by architecture code to keep track of
410 * memory type of pfn mappings (remap_pfn_range, vm_insert_pfn)
411 *
412 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
413 * untrack can be called for a specific region indicated by pfn and size or
414 * can be for the entire vma (in which case size can be zero).
415 */
416static inline void untrack_pfn_vma(struct vm_area_struct *vma,
417 unsigned long pfn, unsigned long size)
418{
419}
420#else
421extern int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot,
422 unsigned long pfn, unsigned long size);
423extern int track_pfn_vma_copy(struct vm_area_struct *vma);
424extern void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn,
425 unsigned long size);
426#endif
427
428#ifndef CONFIG_TRANSPARENT_HUGEPAGE
429static inline int pmd_trans_huge(pmd_t pmd)
430{
431 return 0;
432}
433static inline int pmd_trans_splitting(pmd_t pmd)
434{
435 return 0;
436}
437#ifndef __HAVE_ARCH_PMD_WRITE
438static inline int pmd_write(pmd_t pmd)
439{
440 BUG();
441 return 0;
442}
443#endif /* __HAVE_ARCH_PMD_WRITE */
444#endif
445
446#endif /* !__ASSEMBLY__ */
447
448#endif /* _ASM_GENERIC_PGTABLE_H */
1#ifndef _ASM_GENERIC_PGTABLE_H
2#define _ASM_GENERIC_PGTABLE_H
3
4#ifndef __ASSEMBLY__
5#ifdef CONFIG_MMU
6
7#include <linux/mm_types.h>
8#include <linux/bug.h>
9
10/*
11 * On almost all architectures and configurations, 0 can be used as the
12 * upper ceiling to free_pgtables(): on many architectures it has the same
13 * effect as using TASK_SIZE. However, there is one configuration which
14 * must impose a more careful limit, to avoid freeing kernel pgtables.
15 */
16#ifndef USER_PGTABLES_CEILING
17#define USER_PGTABLES_CEILING 0UL
18#endif
19
20#ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
21extern int ptep_set_access_flags(struct vm_area_struct *vma,
22 unsigned long address, pte_t *ptep,
23 pte_t entry, int dirty);
24#endif
25
26#ifndef __HAVE_ARCH_PMDP_SET_ACCESS_FLAGS
27extern int pmdp_set_access_flags(struct vm_area_struct *vma,
28 unsigned long address, pmd_t *pmdp,
29 pmd_t entry, int dirty);
30#endif
31
32#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
33static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
34 unsigned long address,
35 pte_t *ptep)
36{
37 pte_t pte = *ptep;
38 int r = 1;
39 if (!pte_young(pte))
40 r = 0;
41 else
42 set_pte_at(vma->vm_mm, address, ptep, pte_mkold(pte));
43 return r;
44}
45#endif
46
47#ifndef __HAVE_ARCH_PMDP_TEST_AND_CLEAR_YOUNG
48#ifdef CONFIG_TRANSPARENT_HUGEPAGE
49static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
50 unsigned long address,
51 pmd_t *pmdp)
52{
53 pmd_t pmd = *pmdp;
54 int r = 1;
55 if (!pmd_young(pmd))
56 r = 0;
57 else
58 set_pmd_at(vma->vm_mm, address, pmdp, pmd_mkold(pmd));
59 return r;
60}
61#else /* CONFIG_TRANSPARENT_HUGEPAGE */
62static inline int pmdp_test_and_clear_young(struct vm_area_struct *vma,
63 unsigned long address,
64 pmd_t *pmdp)
65{
66 BUG();
67 return 0;
68}
69#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
70#endif
71
72#ifndef __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
73int ptep_clear_flush_young(struct vm_area_struct *vma,
74 unsigned long address, pte_t *ptep);
75#endif
76
77#ifndef __HAVE_ARCH_PMDP_CLEAR_YOUNG_FLUSH
78int pmdp_clear_flush_young(struct vm_area_struct *vma,
79 unsigned long address, pmd_t *pmdp);
80#endif
81
82#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR
83static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
84 unsigned long address,
85 pte_t *ptep)
86{
87 pte_t pte = *ptep;
88 pte_clear(mm, address, ptep);
89 return pte;
90}
91#endif
92
93#ifndef __HAVE_ARCH_PMDP_GET_AND_CLEAR
94#ifdef CONFIG_TRANSPARENT_HUGEPAGE
95static inline pmd_t pmdp_get_and_clear(struct mm_struct *mm,
96 unsigned long address,
97 pmd_t *pmdp)
98{
99 pmd_t pmd = *pmdp;
100 pmd_clear(pmdp);
101 return pmd;
102}
103#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
104#endif
105
106#ifndef __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
107static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm,
108 unsigned long address, pte_t *ptep,
109 int full)
110{
111 pte_t pte;
112 pte = ptep_get_and_clear(mm, address, ptep);
113 return pte;
114}
115#endif
116
117/*
118 * Some architectures may be able to avoid expensive synchronization
119 * primitives when modifications are made to PTE's which are already
120 * not present, or in the process of an address space destruction.
121 */
122#ifndef __HAVE_ARCH_PTE_CLEAR_NOT_PRESENT_FULL
123static inline void pte_clear_not_present_full(struct mm_struct *mm,
124 unsigned long address,
125 pte_t *ptep,
126 int full)
127{
128 pte_clear(mm, address, ptep);
129}
130#endif
131
132#ifndef __HAVE_ARCH_PTEP_CLEAR_FLUSH
133extern pte_t ptep_clear_flush(struct vm_area_struct *vma,
134 unsigned long address,
135 pte_t *ptep);
136#endif
137
138#ifndef __HAVE_ARCH_PMDP_CLEAR_FLUSH
139extern pmd_t pmdp_clear_flush(struct vm_area_struct *vma,
140 unsigned long address,
141 pmd_t *pmdp);
142#endif
143
144#ifndef __HAVE_ARCH_PTEP_SET_WRPROTECT
145struct mm_struct;
146static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long address, pte_t *ptep)
147{
148 pte_t old_pte = *ptep;
149 set_pte_at(mm, address, ptep, pte_wrprotect(old_pte));
150}
151#endif
152
153#ifndef __HAVE_ARCH_PMDP_SET_WRPROTECT
154#ifdef CONFIG_TRANSPARENT_HUGEPAGE
155static inline void pmdp_set_wrprotect(struct mm_struct *mm,
156 unsigned long address, pmd_t *pmdp)
157{
158 pmd_t old_pmd = *pmdp;
159 set_pmd_at(mm, address, pmdp, pmd_wrprotect(old_pmd));
160}
161#else /* CONFIG_TRANSPARENT_HUGEPAGE */
162static inline void pmdp_set_wrprotect(struct mm_struct *mm,
163 unsigned long address, pmd_t *pmdp)
164{
165 BUG();
166}
167#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
168#endif
169
170#ifndef __HAVE_ARCH_PMDP_SPLITTING_FLUSH
171extern void pmdp_splitting_flush(struct vm_area_struct *vma,
172 unsigned long address, pmd_t *pmdp);
173#endif
174
175#ifndef __HAVE_ARCH_PGTABLE_DEPOSIT
176extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
177 pgtable_t pgtable);
178#endif
179
180#ifndef __HAVE_ARCH_PGTABLE_WITHDRAW
181extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp);
182#endif
183
184#ifndef __HAVE_ARCH_PMDP_INVALIDATE
185extern void pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
186 pmd_t *pmdp);
187#endif
188
189#ifndef __HAVE_ARCH_PTE_SAME
190static inline int pte_same(pte_t pte_a, pte_t pte_b)
191{
192 return pte_val(pte_a) == pte_val(pte_b);
193}
194#endif
195
196#ifndef __HAVE_ARCH_PTE_UNUSED
197/*
198 * Some architectures provide facilities to virtualization guests
199 * so that they can flag allocated pages as unused. This allows the
200 * host to transparently reclaim unused pages. This function returns
201 * whether the pte's page is unused.
202 */
203static inline int pte_unused(pte_t pte)
204{
205 return 0;
206}
207#endif
208
209#ifndef __HAVE_ARCH_PMD_SAME
210#ifdef CONFIG_TRANSPARENT_HUGEPAGE
211static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
212{
213 return pmd_val(pmd_a) == pmd_val(pmd_b);
214}
215#else /* CONFIG_TRANSPARENT_HUGEPAGE */
216static inline int pmd_same(pmd_t pmd_a, pmd_t pmd_b)
217{
218 BUG();
219 return 0;
220}
221#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
222#endif
223
224#ifndef __HAVE_ARCH_PGD_OFFSET_GATE
225#define pgd_offset_gate(mm, addr) pgd_offset(mm, addr)
226#endif
227
228#ifndef __HAVE_ARCH_MOVE_PTE
229#define move_pte(pte, prot, old_addr, new_addr) (pte)
230#endif
231
232#ifndef pte_accessible
233# define pte_accessible(mm, pte) ((void)(pte), 1)
234#endif
235
236#ifndef flush_tlb_fix_spurious_fault
237#define flush_tlb_fix_spurious_fault(vma, address) flush_tlb_page(vma, address)
238#endif
239
240#ifndef pgprot_noncached
241#define pgprot_noncached(prot) (prot)
242#endif
243
244#ifndef pgprot_writecombine
245#define pgprot_writecombine pgprot_noncached
246#endif
247
248/*
249 * When walking page tables, get the address of the next boundary,
250 * or the end address of the range if that comes earlier. Although no
251 * vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.
252 */
253
254#define pgd_addr_end(addr, end) \
255({ unsigned long __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \
256 (__boundary - 1 < (end) - 1)? __boundary: (end); \
257})
258
259#ifndef pud_addr_end
260#define pud_addr_end(addr, end) \
261({ unsigned long __boundary = ((addr) + PUD_SIZE) & PUD_MASK; \
262 (__boundary - 1 < (end) - 1)? __boundary: (end); \
263})
264#endif
265
266#ifndef pmd_addr_end
267#define pmd_addr_end(addr, end) \
268({ unsigned long __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \
269 (__boundary - 1 < (end) - 1)? __boundary: (end); \
270})
271#endif
272
273/*
274 * When walking page tables, we usually want to skip any p?d_none entries;
275 * and any p?d_bad entries - reporting the error before resetting to none.
276 * Do the tests inline, but report and clear the bad entry in mm/memory.c.
277 */
278void pgd_clear_bad(pgd_t *);
279void pud_clear_bad(pud_t *);
280void pmd_clear_bad(pmd_t *);
281
282static inline int pgd_none_or_clear_bad(pgd_t *pgd)
283{
284 if (pgd_none(*pgd))
285 return 1;
286 if (unlikely(pgd_bad(*pgd))) {
287 pgd_clear_bad(pgd);
288 return 1;
289 }
290 return 0;
291}
292
293static inline int pud_none_or_clear_bad(pud_t *pud)
294{
295 if (pud_none(*pud))
296 return 1;
297 if (unlikely(pud_bad(*pud))) {
298 pud_clear_bad(pud);
299 return 1;
300 }
301 return 0;
302}
303
304static inline int pmd_none_or_clear_bad(pmd_t *pmd)
305{
306 if (pmd_none(*pmd))
307 return 1;
308 if (unlikely(pmd_bad(*pmd))) {
309 pmd_clear_bad(pmd);
310 return 1;
311 }
312 return 0;
313}
314
315static inline pte_t __ptep_modify_prot_start(struct mm_struct *mm,
316 unsigned long addr,
317 pte_t *ptep)
318{
319 /*
320 * Get the current pte state, but zero it out to make it
321 * non-present, preventing the hardware from asynchronously
322 * updating it.
323 */
324 return ptep_get_and_clear(mm, addr, ptep);
325}
326
327static inline void __ptep_modify_prot_commit(struct mm_struct *mm,
328 unsigned long addr,
329 pte_t *ptep, pte_t pte)
330{
331 /*
332 * The pte is non-present, so there's no hardware state to
333 * preserve.
334 */
335 set_pte_at(mm, addr, ptep, pte);
336}
337
338#ifndef __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION
339/*
340 * Start a pte protection read-modify-write transaction, which
341 * protects against asynchronous hardware modifications to the pte.
342 * The intention is not to prevent the hardware from making pte
343 * updates, but to prevent any updates it may make from being lost.
344 *
345 * This does not protect against other software modifications of the
346 * pte; the appropriate pte lock must be held over the transation.
347 *
348 * Note that this interface is intended to be batchable, meaning that
349 * ptep_modify_prot_commit may not actually update the pte, but merely
350 * queue the update to be done at some later time. The update must be
351 * actually committed before the pte lock is released, however.
352 */
353static inline pte_t ptep_modify_prot_start(struct mm_struct *mm,
354 unsigned long addr,
355 pte_t *ptep)
356{
357 return __ptep_modify_prot_start(mm, addr, ptep);
358}
359
360/*
361 * Commit an update to a pte, leaving any hardware-controlled bits in
362 * the PTE unmodified.
363 */
364static inline void ptep_modify_prot_commit(struct mm_struct *mm,
365 unsigned long addr,
366 pte_t *ptep, pte_t pte)
367{
368 __ptep_modify_prot_commit(mm, addr, ptep, pte);
369}
370#endif /* __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION */
371#endif /* CONFIG_MMU */
372
373/*
374 * A facility to provide lazy MMU batching. This allows PTE updates and
375 * page invalidations to be delayed until a call to leave lazy MMU mode
376 * is issued. Some architectures may benefit from doing this, and it is
377 * beneficial for both shadow and direct mode hypervisors, which may batch
378 * the PTE updates which happen during this window. Note that using this
379 * interface requires that read hazards be removed from the code. A read
380 * hazard could result in the direct mode hypervisor case, since the actual
381 * write to the page tables may not yet have taken place, so reads though
382 * a raw PTE pointer after it has been modified are not guaranteed to be
383 * up to date. This mode can only be entered and left under the protection of
384 * the page table locks for all page tables which may be modified. In the UP
385 * case, this is required so that preemption is disabled, and in the SMP case,
386 * it must synchronize the delayed page table writes properly on other CPUs.
387 */
388#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE
389#define arch_enter_lazy_mmu_mode() do {} while (0)
390#define arch_leave_lazy_mmu_mode() do {} while (0)
391#define arch_flush_lazy_mmu_mode() do {} while (0)
392#endif
393
394/*
395 * A facility to provide batching of the reload of page tables and
396 * other process state with the actual context switch code for
397 * paravirtualized guests. By convention, only one of the batched
398 * update (lazy) modes (CPU, MMU) should be active at any given time,
399 * entry should never be nested, and entry and exits should always be
400 * paired. This is for sanity of maintaining and reasoning about the
401 * kernel code. In this case, the exit (end of the context switch) is
402 * in architecture-specific code, and so doesn't need a generic
403 * definition.
404 */
405#ifndef __HAVE_ARCH_START_CONTEXT_SWITCH
406#define arch_start_context_switch(prev) do {} while (0)
407#endif
408
409#ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY
410static inline int pte_soft_dirty(pte_t pte)
411{
412 return 0;
413}
414
415static inline int pmd_soft_dirty(pmd_t pmd)
416{
417 return 0;
418}
419
420static inline pte_t pte_mksoft_dirty(pte_t pte)
421{
422 return pte;
423}
424
425static inline pmd_t pmd_mksoft_dirty(pmd_t pmd)
426{
427 return pmd;
428}
429
430static inline pte_t pte_swp_mksoft_dirty(pte_t pte)
431{
432 return pte;
433}
434
435static inline int pte_swp_soft_dirty(pte_t pte)
436{
437 return 0;
438}
439
440static inline pte_t pte_swp_clear_soft_dirty(pte_t pte)
441{
442 return pte;
443}
444
445static inline pte_t pte_file_clear_soft_dirty(pte_t pte)
446{
447 return pte;
448}
449
450static inline pte_t pte_file_mksoft_dirty(pte_t pte)
451{
452 return pte;
453}
454
455static inline int pte_file_soft_dirty(pte_t pte)
456{
457 return 0;
458}
459#endif
460
461#ifndef __HAVE_PFNMAP_TRACKING
462/*
463 * Interfaces that can be used by architecture code to keep track of
464 * memory type of pfn mappings specified by the remap_pfn_range,
465 * vm_insert_pfn.
466 */
467
468/*
469 * track_pfn_remap is called when a _new_ pfn mapping is being established
470 * by remap_pfn_range() for physical range indicated by pfn and size.
471 */
472static inline int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
473 unsigned long pfn, unsigned long addr,
474 unsigned long size)
475{
476 return 0;
477}
478
479/*
480 * track_pfn_insert is called when a _new_ single pfn is established
481 * by vm_insert_pfn().
482 */
483static inline int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
484 unsigned long pfn)
485{
486 return 0;
487}
488
489/*
490 * track_pfn_copy is called when vma that is covering the pfnmap gets
491 * copied through copy_page_range().
492 */
493static inline int track_pfn_copy(struct vm_area_struct *vma)
494{
495 return 0;
496}
497
498/*
499 * untrack_pfn_vma is called while unmapping a pfnmap for a region.
500 * untrack can be called for a specific region indicated by pfn and size or
501 * can be for the entire vma (in which case pfn, size are zero).
502 */
503static inline void untrack_pfn(struct vm_area_struct *vma,
504 unsigned long pfn, unsigned long size)
505{
506}
507#else
508extern int track_pfn_remap(struct vm_area_struct *vma, pgprot_t *prot,
509 unsigned long pfn, unsigned long addr,
510 unsigned long size);
511extern int track_pfn_insert(struct vm_area_struct *vma, pgprot_t *prot,
512 unsigned long pfn);
513extern int track_pfn_copy(struct vm_area_struct *vma);
514extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn,
515 unsigned long size);
516#endif
517
518#ifdef __HAVE_COLOR_ZERO_PAGE
519static inline int is_zero_pfn(unsigned long pfn)
520{
521 extern unsigned long zero_pfn;
522 unsigned long offset_from_zero_pfn = pfn - zero_pfn;
523 return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
524}
525
526#define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr))
527
528#else
529static inline int is_zero_pfn(unsigned long pfn)
530{
531 extern unsigned long zero_pfn;
532 return pfn == zero_pfn;
533}
534
535static inline unsigned long my_zero_pfn(unsigned long addr)
536{
537 extern unsigned long zero_pfn;
538 return zero_pfn;
539}
540#endif
541
542#ifdef CONFIG_MMU
543
544#ifndef CONFIG_TRANSPARENT_HUGEPAGE
545static inline int pmd_trans_huge(pmd_t pmd)
546{
547 return 0;
548}
549static inline int pmd_trans_splitting(pmd_t pmd)
550{
551 return 0;
552}
553#ifndef __HAVE_ARCH_PMD_WRITE
554static inline int pmd_write(pmd_t pmd)
555{
556 BUG();
557 return 0;
558}
559#endif /* __HAVE_ARCH_PMD_WRITE */
560#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
561
562#ifndef pmd_read_atomic
563static inline pmd_t pmd_read_atomic(pmd_t *pmdp)
564{
565 /*
566 * Depend on compiler for an atomic pmd read. NOTE: this is
567 * only going to work, if the pmdval_t isn't larger than
568 * an unsigned long.
569 */
570 return *pmdp;
571}
572#endif
573
574#ifndef pmd_move_must_withdraw
575static inline int pmd_move_must_withdraw(spinlock_t *new_pmd_ptl,
576 spinlock_t *old_pmd_ptl)
577{
578 /*
579 * With split pmd lock we also need to move preallocated
580 * PTE page table if new_pmd is on different PMD page table.
581 */
582 return new_pmd_ptl != old_pmd_ptl;
583}
584#endif
585
586/*
587 * This function is meant to be used by sites walking pagetables with
588 * the mmap_sem hold in read mode to protect against MADV_DONTNEED and
589 * transhuge page faults. MADV_DONTNEED can convert a transhuge pmd
590 * into a null pmd and the transhuge page fault can convert a null pmd
591 * into an hugepmd or into a regular pmd (if the hugepage allocation
592 * fails). While holding the mmap_sem in read mode the pmd becomes
593 * stable and stops changing under us only if it's not null and not a
594 * transhuge pmd. When those races occurs and this function makes a
595 * difference vs the standard pmd_none_or_clear_bad, the result is
596 * undefined so behaving like if the pmd was none is safe (because it
597 * can return none anyway). The compiler level barrier() is critically
598 * important to compute the two checks atomically on the same pmdval.
599 *
600 * For 32bit kernels with a 64bit large pmd_t this automatically takes
601 * care of reading the pmd atomically to avoid SMP race conditions
602 * against pmd_populate() when the mmap_sem is hold for reading by the
603 * caller (a special atomic read not done by "gcc" as in the generic
604 * version above, is also needed when THP is disabled because the page
605 * fault can populate the pmd from under us).
606 */
607static inline int pmd_none_or_trans_huge_or_clear_bad(pmd_t *pmd)
608{
609 pmd_t pmdval = pmd_read_atomic(pmd);
610 /*
611 * The barrier will stabilize the pmdval in a register or on
612 * the stack so that it will stop changing under the code.
613 *
614 * When CONFIG_TRANSPARENT_HUGEPAGE=y on x86 32bit PAE,
615 * pmd_read_atomic is allowed to return a not atomic pmdval
616 * (for example pointing to an hugepage that has never been
617 * mapped in the pmd). The below checks will only care about
618 * the low part of the pmd with 32bit PAE x86 anyway, with the
619 * exception of pmd_none(). So the important thing is that if
620 * the low part of the pmd is found null, the high part will
621 * be also null or the pmd_none() check below would be
622 * confused.
623 */
624#ifdef CONFIG_TRANSPARENT_HUGEPAGE
625 barrier();
626#endif
627 if (pmd_none(pmdval) || pmd_trans_huge(pmdval))
628 return 1;
629 if (unlikely(pmd_bad(pmdval))) {
630 pmd_clear_bad(pmd);
631 return 1;
632 }
633 return 0;
634}
635
636/*
637 * This is a noop if Transparent Hugepage Support is not built into
638 * the kernel. Otherwise it is equivalent to
639 * pmd_none_or_trans_huge_or_clear_bad(), and shall only be called in
640 * places that already verified the pmd is not none and they want to
641 * walk ptes while holding the mmap sem in read mode (write mode don't
642 * need this). If THP is not enabled, the pmd can't go away under the
643 * code even if MADV_DONTNEED runs, but if THP is enabled we need to
644 * run a pmd_trans_unstable before walking the ptes after
645 * split_huge_page_pmd returns (because it may have run when the pmd
646 * become null, but then a page fault can map in a THP and not a
647 * regular page).
648 */
649static inline int pmd_trans_unstable(pmd_t *pmd)
650{
651#ifdef CONFIG_TRANSPARENT_HUGEPAGE
652 return pmd_none_or_trans_huge_or_clear_bad(pmd);
653#else
654 return 0;
655#endif
656}
657
658#ifdef CONFIG_NUMA_BALANCING
659#ifdef CONFIG_ARCH_USES_NUMA_PROT_NONE
660/*
661 * _PAGE_NUMA works identical to _PAGE_PROTNONE (it's actually the
662 * same bit too). It's set only when _PAGE_PRESET is not set and it's
663 * never set if _PAGE_PRESENT is set.
664 *
665 * pte/pmd_present() returns true if pte/pmd_numa returns true. Page
666 * fault triggers on those regions if pte/pmd_numa returns true
667 * (because _PAGE_PRESENT is not set).
668 */
669#ifndef pte_numa
670static inline int pte_numa(pte_t pte)
671{
672 return (pte_flags(pte) &
673 (_PAGE_NUMA|_PAGE_PRESENT)) == _PAGE_NUMA;
674}
675#endif
676
677#ifndef pmd_numa
678static inline int pmd_numa(pmd_t pmd)
679{
680 return (pmd_flags(pmd) &
681 (_PAGE_NUMA|_PAGE_PRESENT)) == _PAGE_NUMA;
682}
683#endif
684
685/*
686 * pte/pmd_mknuma sets the _PAGE_ACCESSED bitflag automatically
687 * because they're called by the NUMA hinting minor page fault. If we
688 * wouldn't set the _PAGE_ACCESSED bitflag here, the TLB miss handler
689 * would be forced to set it later while filling the TLB after we
690 * return to userland. That would trigger a second write to memory
691 * that we optimize away by setting _PAGE_ACCESSED here.
692 */
693#ifndef pte_mknonnuma
694static inline pte_t pte_mknonnuma(pte_t pte)
695{
696 pteval_t val = pte_val(pte);
697
698 val &= ~_PAGE_NUMA;
699 val |= (_PAGE_PRESENT|_PAGE_ACCESSED);
700 return __pte(val);
701}
702#endif
703
704#ifndef pmd_mknonnuma
705static inline pmd_t pmd_mknonnuma(pmd_t pmd)
706{
707 pmdval_t val = pmd_val(pmd);
708
709 val &= ~_PAGE_NUMA;
710 val |= (_PAGE_PRESENT|_PAGE_ACCESSED);
711
712 return __pmd(val);
713}
714#endif
715
716#ifndef pte_mknuma
717static inline pte_t pte_mknuma(pte_t pte)
718{
719 pteval_t val = pte_val(pte);
720
721 val &= ~_PAGE_PRESENT;
722 val |= _PAGE_NUMA;
723
724 return __pte(val);
725}
726#endif
727
728#ifndef ptep_set_numa
729static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr,
730 pte_t *ptep)
731{
732 pte_t ptent = *ptep;
733
734 ptent = pte_mknuma(ptent);
735 set_pte_at(mm, addr, ptep, ptent);
736 return;
737}
738#endif
739
740#ifndef pmd_mknuma
741static inline pmd_t pmd_mknuma(pmd_t pmd)
742{
743 pmdval_t val = pmd_val(pmd);
744
745 val &= ~_PAGE_PRESENT;
746 val |= _PAGE_NUMA;
747
748 return __pmd(val);
749}
750#endif
751
752#ifndef pmdp_set_numa
753static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr,
754 pmd_t *pmdp)
755{
756 pmd_t pmd = *pmdp;
757
758 pmd = pmd_mknuma(pmd);
759 set_pmd_at(mm, addr, pmdp, pmd);
760 return;
761}
762#endif
763#else
764extern int pte_numa(pte_t pte);
765extern int pmd_numa(pmd_t pmd);
766extern pte_t pte_mknonnuma(pte_t pte);
767extern pmd_t pmd_mknonnuma(pmd_t pmd);
768extern pte_t pte_mknuma(pte_t pte);
769extern pmd_t pmd_mknuma(pmd_t pmd);
770extern void ptep_set_numa(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
771extern void pmdp_set_numa(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp);
772#endif /* CONFIG_ARCH_USES_NUMA_PROT_NONE */
773#else
774static inline int pmd_numa(pmd_t pmd)
775{
776 return 0;
777}
778
779static inline int pte_numa(pte_t pte)
780{
781 return 0;
782}
783
784static inline pte_t pte_mknonnuma(pte_t pte)
785{
786 return pte;
787}
788
789static inline pmd_t pmd_mknonnuma(pmd_t pmd)
790{
791 return pmd;
792}
793
794static inline pte_t pte_mknuma(pte_t pte)
795{
796 return pte;
797}
798
799static inline void ptep_set_numa(struct mm_struct *mm, unsigned long addr,
800 pte_t *ptep)
801{
802 return;
803}
804
805
806static inline pmd_t pmd_mknuma(pmd_t pmd)
807{
808 return pmd;
809}
810
811static inline void pmdp_set_numa(struct mm_struct *mm, unsigned long addr,
812 pmd_t *pmdp)
813{
814 return ;
815}
816#endif /* CONFIG_NUMA_BALANCING */
817
818#endif /* CONFIG_MMU */
819
820#endif /* !__ASSEMBLY__ */
821
822#ifndef io_remap_pfn_range
823#define io_remap_pfn_range remap_pfn_range
824#endif
825
826#endif /* _ASM_GENERIC_PGTABLE_H */