xref: /linux/arch/arm/include/asm/tlbflush.h (revision f8324e20f8289dffc646d64366332e05eaacab25)
1 /*
2  *  arch/arm/include/asm/tlbflush.h
3  *
4  *  Copyright (C) 1999-2003 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 #ifndef _ASMARM_TLBFLUSH_H
11 #define _ASMARM_TLBFLUSH_H
12 
13 
14 #ifndef CONFIG_MMU
15 
16 #define tlb_flush(tlb)	((void) tlb)
17 
18 #else /* CONFIG_MMU */
19 
20 #include <asm/glue.h>
21 
22 #define TLB_V3_PAGE	(1 << 0)
23 #define TLB_V4_U_PAGE	(1 << 1)
24 #define TLB_V4_D_PAGE	(1 << 2)
25 #define TLB_V4_I_PAGE	(1 << 3)
26 #define TLB_V6_U_PAGE	(1 << 4)
27 #define TLB_V6_D_PAGE	(1 << 5)
28 #define TLB_V6_I_PAGE	(1 << 6)
29 
30 #define TLB_V3_FULL	(1 << 8)
31 #define TLB_V4_U_FULL	(1 << 9)
32 #define TLB_V4_D_FULL	(1 << 10)
33 #define TLB_V4_I_FULL	(1 << 11)
34 #define TLB_V6_U_FULL	(1 << 12)
35 #define TLB_V6_D_FULL	(1 << 13)
36 #define TLB_V6_I_FULL	(1 << 14)
37 
38 #define TLB_V6_U_ASID	(1 << 16)
39 #define TLB_V6_D_ASID	(1 << 17)
40 #define TLB_V6_I_ASID	(1 << 18)
41 
42 #define TLB_BTB		(1 << 28)
43 
44 /* Unified Inner Shareable TLB operations (ARMv7 MP extensions) */
45 #define TLB_V7_UIS_PAGE	(1 << 19)
46 #define TLB_V7_UIS_FULL (1 << 20)
47 #define TLB_V7_UIS_ASID (1 << 21)
48 
49 /* Inner Shareable BTB operation (ARMv7 MP extensions) */
50 #define TLB_V7_IS_BTB	(1 << 22)
51 
52 #define TLB_L2CLEAN_FR	(1 << 29)		/* Feroceon */
53 #define TLB_DCLEAN	(1 << 30)
54 #define TLB_WB		(1 << 31)
55 
56 /*
57  *	MMU TLB Model
58  *	=============
59  *
60  *	We have the following to choose from:
61  *	  v3    - ARMv3
62  *	  v4    - ARMv4 without write buffer
63  *	  v4wb  - ARMv4 with write buffer without I TLB flush entry instruction
64  *	  v4wbi - ARMv4 with write buffer with I TLB flush entry instruction
65  *	  fr    - Feroceon (v4wbi with non-outer-cacheable page table walks)
66  *	  fa    - Faraday (v4 with write buffer with UTLB and branch target buffer (BTB))
67  *	  v6wbi - ARMv6 with write buffer with I TLB flush entry instruction
68  *	  v7wbi - identical to v6wbi
69  */
70 #undef _TLB
71 #undef MULTI_TLB
72 
73 #define v3_tlb_flags	(TLB_V3_FULL | TLB_V3_PAGE)
74 
75 #ifdef CONFIG_CPU_TLB_V3
76 # define v3_possible_flags	v3_tlb_flags
77 # define v3_always_flags	v3_tlb_flags
78 # ifdef _TLB
79 #  define MULTI_TLB 1
80 # else
81 #  define _TLB v3
82 # endif
83 #else
84 # define v3_possible_flags	0
85 # define v3_always_flags	(-1UL)
86 #endif
87 
88 #define v4_tlb_flags	(TLB_V4_U_FULL | TLB_V4_U_PAGE)
89 
90 #ifdef CONFIG_CPU_TLB_V4WT
91 # define v4_possible_flags	v4_tlb_flags
92 # define v4_always_flags	v4_tlb_flags
93 # ifdef _TLB
94 #  define MULTI_TLB 1
95 # else
96 #  define _TLB v4
97 # endif
98 #else
99 # define v4_possible_flags	0
100 # define v4_always_flags	(-1UL)
101 #endif
102 
103 #define fa_tlb_flags	(TLB_WB | TLB_BTB | TLB_DCLEAN | \
104 			 TLB_V4_U_FULL | TLB_V4_U_PAGE)
105 
106 #ifdef CONFIG_CPU_TLB_FA
107 # define fa_possible_flags	fa_tlb_flags
108 # define fa_always_flags	fa_tlb_flags
109 # ifdef _TLB
110 #  define MULTI_TLB 1
111 # else
112 #  define _TLB fa
113 # endif
114 #else
115 # define fa_possible_flags	0
116 # define fa_always_flags	(-1UL)
117 #endif
118 
119 #define v4wbi_tlb_flags	(TLB_WB | TLB_DCLEAN | \
120 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
121 			 TLB_V4_I_PAGE | TLB_V4_D_PAGE)
122 
123 #ifdef CONFIG_CPU_TLB_V4WBI
124 # define v4wbi_possible_flags	v4wbi_tlb_flags
125 # define v4wbi_always_flags	v4wbi_tlb_flags
126 # ifdef _TLB
127 #  define MULTI_TLB 1
128 # else
129 #  define _TLB v4wbi
130 # endif
131 #else
132 # define v4wbi_possible_flags	0
133 # define v4wbi_always_flags	(-1UL)
134 #endif
135 
136 #define fr_tlb_flags	(TLB_WB | TLB_DCLEAN | TLB_L2CLEAN_FR | \
137 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
138 			 TLB_V4_I_PAGE | TLB_V4_D_PAGE)
139 
140 #ifdef CONFIG_CPU_TLB_FEROCEON
141 # define fr_possible_flags	fr_tlb_flags
142 # define fr_always_flags	fr_tlb_flags
143 # ifdef _TLB
144 #  define MULTI_TLB 1
145 # else
146 #  define _TLB v4wbi
147 # endif
148 #else
149 # define fr_possible_flags	0
150 # define fr_always_flags	(-1UL)
151 #endif
152 
153 #define v4wb_tlb_flags	(TLB_WB | TLB_DCLEAN | \
154 			 TLB_V4_I_FULL | TLB_V4_D_FULL | \
155 			 TLB_V4_D_PAGE)
156 
157 #ifdef CONFIG_CPU_TLB_V4WB
158 # define v4wb_possible_flags	v4wb_tlb_flags
159 # define v4wb_always_flags	v4wb_tlb_flags
160 # ifdef _TLB
161 #  define MULTI_TLB 1
162 # else
163 #  define _TLB v4wb
164 # endif
165 #else
166 # define v4wb_possible_flags	0
167 # define v4wb_always_flags	(-1UL)
168 #endif
169 
170 #define v6wbi_tlb_flags (TLB_WB | TLB_DCLEAN | TLB_BTB | \
171 			 TLB_V6_I_FULL | TLB_V6_D_FULL | \
172 			 TLB_V6_I_PAGE | TLB_V6_D_PAGE | \
173 			 TLB_V6_I_ASID | TLB_V6_D_ASID)
174 
175 #ifdef CONFIG_CPU_TLB_V6
176 # define v6wbi_possible_flags	v6wbi_tlb_flags
177 # define v6wbi_always_flags	v6wbi_tlb_flags
178 # ifdef _TLB
179 #  define MULTI_TLB 1
180 # else
181 #  define _TLB v6wbi
182 # endif
183 #else
184 # define v6wbi_possible_flags	0
185 # define v6wbi_always_flags	(-1UL)
186 #endif
187 
188 #ifdef CONFIG_SMP
189 #define v7wbi_tlb_flags (TLB_WB | TLB_DCLEAN | TLB_V7_IS_BTB | \
190 			 TLB_V7_UIS_FULL | TLB_V7_UIS_PAGE | TLB_V7_UIS_ASID)
191 #else
192 #define v7wbi_tlb_flags (TLB_WB | TLB_DCLEAN | TLB_BTB | \
193 			 TLB_V6_U_FULL | TLB_V6_U_PAGE | TLB_V6_U_ASID)
194 #endif
195 
196 #ifdef CONFIG_CPU_TLB_V7
197 # define v7wbi_possible_flags	v7wbi_tlb_flags
198 # define v7wbi_always_flags	v7wbi_tlb_flags
199 # ifdef _TLB
200 #  define MULTI_TLB 1
201 # else
202 #  define _TLB v7wbi
203 # endif
204 #else
205 # define v7wbi_possible_flags	0
206 # define v7wbi_always_flags	(-1UL)
207 #endif
208 
209 #ifndef _TLB
210 #error Unknown TLB model
211 #endif
212 
213 #ifndef __ASSEMBLY__
214 
215 #include <linux/sched.h>
216 
217 struct cpu_tlb_fns {
218 	void (*flush_user_range)(unsigned long, unsigned long, struct vm_area_struct *);
219 	void (*flush_kern_range)(unsigned long, unsigned long);
220 	unsigned long tlb_flags;
221 };
222 
223 /*
224  * Select the calling method
225  */
226 #ifdef MULTI_TLB
227 
228 #define __cpu_flush_user_tlb_range	cpu_tlb.flush_user_range
229 #define __cpu_flush_kern_tlb_range	cpu_tlb.flush_kern_range
230 
231 #else
232 
233 #define __cpu_flush_user_tlb_range	__glue(_TLB,_flush_user_tlb_range)
234 #define __cpu_flush_kern_tlb_range	__glue(_TLB,_flush_kern_tlb_range)
235 
236 extern void __cpu_flush_user_tlb_range(unsigned long, unsigned long, struct vm_area_struct *);
237 extern void __cpu_flush_kern_tlb_range(unsigned long, unsigned long);
238 
239 #endif
240 
241 extern struct cpu_tlb_fns cpu_tlb;
242 
243 #define __cpu_tlb_flags			cpu_tlb.tlb_flags
244 
245 /*
246  *	TLB Management
247  *	==============
248  *
249  *	The arch/arm/mm/tlb-*.S files implement these methods.
250  *
251  *	The TLB specific code is expected to perform whatever tests it
252  *	needs to determine if it should invalidate the TLB for each
253  *	call.  Start addresses are inclusive and end addresses are
254  *	exclusive; it is safe to round these addresses down.
255  *
256  *	flush_tlb_all()
257  *
258  *		Invalidate the entire TLB.
259  *
260  *	flush_tlb_mm(mm)
261  *
262  *		Invalidate all TLB entries in a particular address
263  *		space.
264  *		- mm	- mm_struct describing address space
265  *
266  *	flush_tlb_range(mm,start,end)
267  *
268  *		Invalidate a range of TLB entries in the specified
269  *		address space.
270  *		- mm	- mm_struct describing address space
271  *		- start - start address (may not be aligned)
272  *		- end	- end address (exclusive, may not be aligned)
273  *
274  *	flush_tlb_page(vaddr,vma)
275  *
276  *		Invalidate the specified page in the specified address range.
277  *		- vaddr - virtual address (may not be aligned)
278  *		- vma	- vma_struct describing address range
279  *
280  *	flush_kern_tlb_page(kaddr)
281  *
282  *		Invalidate the TLB entry for the specified page.  The address
283  *		will be in the kernels virtual memory space.  Current uses
284  *		only require the D-TLB to be invalidated.
285  *		- kaddr - Kernel virtual memory address
286  */
287 
288 /*
289  * We optimise the code below by:
290  *  - building a set of TLB flags that might be set in __cpu_tlb_flags
291  *  - building a set of TLB flags that will always be set in __cpu_tlb_flags
292  *  - if we're going to need __cpu_tlb_flags, access it once and only once
293  *
294  * This allows us to build optimal assembly for the single-CPU type case,
295  * and as close to optimal given the compiler constrants for multi-CPU
296  * case.  We could do better for the multi-CPU case if the compiler
297  * implemented the "%?" method, but this has been discontinued due to too
298  * many people getting it wrong.
299  */
300 #define possible_tlb_flags	(v3_possible_flags | \
301 				 v4_possible_flags | \
302 				 v4wbi_possible_flags | \
303 				 fr_possible_flags | \
304 				 v4wb_possible_flags | \
305 				 fa_possible_flags | \
306 				 v6wbi_possible_flags | \
307 				 v7wbi_possible_flags)
308 
309 #define always_tlb_flags	(v3_always_flags & \
310 				 v4_always_flags & \
311 				 v4wbi_always_flags & \
312 				 fr_always_flags & \
313 				 v4wb_always_flags & \
314 				 fa_always_flags & \
315 				 v6wbi_always_flags & \
316 				 v7wbi_always_flags)
317 
318 #define tlb_flag(f)	((always_tlb_flags & (f)) || (__tlb_flag & possible_tlb_flags & (f)))
319 
320 static inline void local_flush_tlb_all(void)
321 {
322 	const int zero = 0;
323 	const unsigned int __tlb_flag = __cpu_tlb_flags;
324 
325 	if (tlb_flag(TLB_WB))
326 		dsb();
327 
328 	if (tlb_flag(TLB_V3_FULL))
329 		asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (zero) : "cc");
330 	if (tlb_flag(TLB_V4_U_FULL | TLB_V6_U_FULL))
331 		asm("mcr p15, 0, %0, c8, c7, 0" : : "r" (zero) : "cc");
332 	if (tlb_flag(TLB_V4_D_FULL | TLB_V6_D_FULL))
333 		asm("mcr p15, 0, %0, c8, c6, 0" : : "r" (zero) : "cc");
334 	if (tlb_flag(TLB_V4_I_FULL | TLB_V6_I_FULL))
335 		asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
336 	if (tlb_flag(TLB_V7_UIS_FULL))
337 		asm("mcr p15, 0, %0, c8, c3, 0" : : "r" (zero) : "cc");
338 
339 	if (tlb_flag(TLB_BTB)) {
340 		/* flush the branch target cache */
341 		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");
342 		dsb();
343 		isb();
344 	}
345 	if (tlb_flag(TLB_V7_IS_BTB)) {
346 		/* flush the branch target cache */
347 		asm("mcr p15, 0, %0, c7, c1, 6" : : "r" (zero) : "cc");
348 		dsb();
349 		isb();
350 	}
351 }
352 
353 static inline void local_flush_tlb_mm(struct mm_struct *mm)
354 {
355 	const int zero = 0;
356 	const int asid = ASID(mm);
357 	const unsigned int __tlb_flag = __cpu_tlb_flags;
358 
359 	if (tlb_flag(TLB_WB))
360 		dsb();
361 
362 	if (cpumask_test_cpu(get_cpu(), mm_cpumask(mm))) {
363 		if (tlb_flag(TLB_V3_FULL))
364 			asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (zero) : "cc");
365 		if (tlb_flag(TLB_V4_U_FULL))
366 			asm("mcr p15, 0, %0, c8, c7, 0" : : "r" (zero) : "cc");
367 		if (tlb_flag(TLB_V4_D_FULL))
368 			asm("mcr p15, 0, %0, c8, c6, 0" : : "r" (zero) : "cc");
369 		if (tlb_flag(TLB_V4_I_FULL))
370 			asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
371 	}
372 	put_cpu();
373 
374 	if (tlb_flag(TLB_V6_U_ASID))
375 		asm("mcr p15, 0, %0, c8, c7, 2" : : "r" (asid) : "cc");
376 	if (tlb_flag(TLB_V6_D_ASID))
377 		asm("mcr p15, 0, %0, c8, c6, 2" : : "r" (asid) : "cc");
378 	if (tlb_flag(TLB_V6_I_ASID))
379 		asm("mcr p15, 0, %0, c8, c5, 2" : : "r" (asid) : "cc");
380 	if (tlb_flag(TLB_V7_UIS_ASID))
381 		asm("mcr p15, 0, %0, c8, c3, 2" : : "r" (asid) : "cc");
382 
383 	if (tlb_flag(TLB_BTB)) {
384 		/* flush the branch target cache */
385 		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");
386 		dsb();
387 	}
388 	if (tlb_flag(TLB_V7_IS_BTB)) {
389 		/* flush the branch target cache */
390 		asm("mcr p15, 0, %0, c7, c1, 6" : : "r" (zero) : "cc");
391 		dsb();
392 		isb();
393 	}
394 }
395 
396 static inline void
397 local_flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr)
398 {
399 	const int zero = 0;
400 	const unsigned int __tlb_flag = __cpu_tlb_flags;
401 
402 	uaddr = (uaddr & PAGE_MASK) | ASID(vma->vm_mm);
403 
404 	if (tlb_flag(TLB_WB))
405 		dsb();
406 
407 	if (cpumask_test_cpu(smp_processor_id(), mm_cpumask(vma->vm_mm))) {
408 		if (tlb_flag(TLB_V3_PAGE))
409 			asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (uaddr) : "cc");
410 		if (tlb_flag(TLB_V4_U_PAGE))
411 			asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (uaddr) : "cc");
412 		if (tlb_flag(TLB_V4_D_PAGE))
413 			asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (uaddr) : "cc");
414 		if (tlb_flag(TLB_V4_I_PAGE))
415 			asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (uaddr) : "cc");
416 		if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
417 			asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
418 	}
419 
420 	if (tlb_flag(TLB_V6_U_PAGE))
421 		asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (uaddr) : "cc");
422 	if (tlb_flag(TLB_V6_D_PAGE))
423 		asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (uaddr) : "cc");
424 	if (tlb_flag(TLB_V6_I_PAGE))
425 		asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (uaddr) : "cc");
426 	if (tlb_flag(TLB_V7_UIS_PAGE))
427 		asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (uaddr) : "cc");
428 
429 	if (tlb_flag(TLB_BTB)) {
430 		/* flush the branch target cache */
431 		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");
432 		dsb();
433 	}
434 	if (tlb_flag(TLB_V7_IS_BTB)) {
435 		/* flush the branch target cache */
436 		asm("mcr p15, 0, %0, c7, c1, 6" : : "r" (zero) : "cc");
437 		dsb();
438 		isb();
439 	}
440 }
441 
442 static inline void local_flush_tlb_kernel_page(unsigned long kaddr)
443 {
444 	const int zero = 0;
445 	const unsigned int __tlb_flag = __cpu_tlb_flags;
446 
447 	kaddr &= PAGE_MASK;
448 
449 	if (tlb_flag(TLB_WB))
450 		dsb();
451 
452 	if (tlb_flag(TLB_V3_PAGE))
453 		asm("mcr p15, 0, %0, c6, c0, 0" : : "r" (kaddr) : "cc");
454 	if (tlb_flag(TLB_V4_U_PAGE))
455 		asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (kaddr) : "cc");
456 	if (tlb_flag(TLB_V4_D_PAGE))
457 		asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (kaddr) : "cc");
458 	if (tlb_flag(TLB_V4_I_PAGE))
459 		asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (kaddr) : "cc");
460 	if (!tlb_flag(TLB_V4_I_PAGE) && tlb_flag(TLB_V4_I_FULL))
461 		asm("mcr p15, 0, %0, c8, c5, 0" : : "r" (zero) : "cc");
462 
463 	if (tlb_flag(TLB_V6_U_PAGE))
464 		asm("mcr p15, 0, %0, c8, c7, 1" : : "r" (kaddr) : "cc");
465 	if (tlb_flag(TLB_V6_D_PAGE))
466 		asm("mcr p15, 0, %0, c8, c6, 1" : : "r" (kaddr) : "cc");
467 	if (tlb_flag(TLB_V6_I_PAGE))
468 		asm("mcr p15, 0, %0, c8, c5, 1" : : "r" (kaddr) : "cc");
469 	if (tlb_flag(TLB_V7_UIS_PAGE))
470 		asm("mcr p15, 0, %0, c8, c3, 1" : : "r" (kaddr) : "cc");
471 
472 	if (tlb_flag(TLB_BTB)) {
473 		/* flush the branch target cache */
474 		asm("mcr p15, 0, %0, c7, c5, 6" : : "r" (zero) : "cc");
475 		dsb();
476 		isb();
477 	}
478 	if (tlb_flag(TLB_V7_IS_BTB)) {
479 		/* flush the branch target cache */
480 		asm("mcr p15, 0, %0, c7, c1, 6" : : "r" (zero) : "cc");
481 		dsb();
482 		isb();
483 	}
484 }
485 
486 /*
487  *	flush_pmd_entry
488  *
489  *	Flush a PMD entry (word aligned, or double-word aligned) to
490  *	RAM if the TLB for the CPU we are running on requires this.
491  *	This is typically used when we are creating PMD entries.
492  *
493  *	clean_pmd_entry
494  *
495  *	Clean (but don't drain the write buffer) if the CPU requires
496  *	these operations.  This is typically used when we are removing
497  *	PMD entries.
498  */
499 static inline void flush_pmd_entry(pmd_t *pmd)
500 {
501 	const unsigned int __tlb_flag = __cpu_tlb_flags;
502 
503 	if (tlb_flag(TLB_DCLEAN))
504 		asm("mcr	p15, 0, %0, c7, c10, 1	@ flush_pmd"
505 			: : "r" (pmd) : "cc");
506 
507 	if (tlb_flag(TLB_L2CLEAN_FR))
508 		asm("mcr	p15, 1, %0, c15, c9, 1  @ L2 flush_pmd"
509 			: : "r" (pmd) : "cc");
510 
511 	if (tlb_flag(TLB_WB))
512 		dsb();
513 }
514 
515 static inline void clean_pmd_entry(pmd_t *pmd)
516 {
517 	const unsigned int __tlb_flag = __cpu_tlb_flags;
518 
519 	if (tlb_flag(TLB_DCLEAN))
520 		asm("mcr	p15, 0, %0, c7, c10, 1	@ flush_pmd"
521 			: : "r" (pmd) : "cc");
522 
523 	if (tlb_flag(TLB_L2CLEAN_FR))
524 		asm("mcr	p15, 1, %0, c15, c9, 1  @ L2 flush_pmd"
525 			: : "r" (pmd) : "cc");
526 }
527 
528 #undef tlb_flag
529 #undef always_tlb_flags
530 #undef possible_tlb_flags
531 
532 /*
533  * Convert calls to our calling convention.
534  */
535 #define local_flush_tlb_range(vma,start,end)	__cpu_flush_user_tlb_range(start,end,vma)
536 #define local_flush_tlb_kernel_range(s,e)	__cpu_flush_kern_tlb_range(s,e)
537 
538 #ifndef CONFIG_SMP
539 #define flush_tlb_all		local_flush_tlb_all
540 #define flush_tlb_mm		local_flush_tlb_mm
541 #define flush_tlb_page		local_flush_tlb_page
542 #define flush_tlb_kernel_page	local_flush_tlb_kernel_page
543 #define flush_tlb_range		local_flush_tlb_range
544 #define flush_tlb_kernel_range	local_flush_tlb_kernel_range
545 #else
546 extern void flush_tlb_all(void);
547 extern void flush_tlb_mm(struct mm_struct *mm);
548 extern void flush_tlb_page(struct vm_area_struct *vma, unsigned long uaddr);
549 extern void flush_tlb_kernel_page(unsigned long kaddr);
550 extern void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end);
551 extern void flush_tlb_kernel_range(unsigned long start, unsigned long end);
552 #endif
553 
554 /*
555  * if PG_dcache_dirty is set for the page, we need to ensure that any
556  * cache entries for the kernels virtual memory range are written
557  * back to the page.
558  */
559 extern void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr,
560 	pte_t *ptep);
561 
562 #endif
563 
564 #endif /* CONFIG_MMU */
565 
566 #endif
567