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1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1999-2006 Helge Deller <deller@gmx.de> (07-13-1999)
7  * Copyright (C) 1999 SuSE GmbH Nuernberg
8  * Copyright (C) 2000 Philipp Rumpf (prumpf@tux.org)
9  *
10  * Cache and TLB management
11  *
12  */
13 
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/mm.h>
17 #include <linux/module.h>
18 #include <linux/seq_file.h>
19 #include <linux/pagemap.h>
20 #include <linux/sched.h>
21 #include <asm/pdc.h>
22 #include <asm/cache.h>
23 #include <asm/cacheflush.h>
24 #include <asm/tlbflush.h>
25 #include <asm/page.h>
26 #include <asm/pgalloc.h>
27 #include <asm/processor.h>
28 #include <asm/sections.h>
29 #include <asm/shmparam.h>
30 
31 int split_tlb __read_mostly;
32 int dcache_stride __read_mostly;
33 int icache_stride __read_mostly;
34 EXPORT_SYMBOL(dcache_stride);
35 
36 void flush_dcache_page_asm(unsigned long phys_addr, unsigned long vaddr);
37 EXPORT_SYMBOL(flush_dcache_page_asm);
38 void flush_icache_page_asm(unsigned long phys_addr, unsigned long vaddr);
39 
40 
41 /* On some machines (e.g. ones with the Merced bus), there can be
42  * only a single PxTLB broadcast at a time; this must be guaranteed
43  * by software.  We put a spinlock around all TLB flushes  to
44  * ensure this.
45  */
46 DEFINE_SPINLOCK(pa_tlb_lock);
47 
48 struct pdc_cache_info cache_info __read_mostly;
49 #ifndef CONFIG_PA20
50 static struct pdc_btlb_info btlb_info __read_mostly;
51 #endif
52 
53 #ifdef CONFIG_SMP
54 void
flush_data_cache(void)55 flush_data_cache(void)
56 {
57 	on_each_cpu(flush_data_cache_local, NULL, 1);
58 }
59 void
flush_instruction_cache(void)60 flush_instruction_cache(void)
61 {
62 	on_each_cpu(flush_instruction_cache_local, NULL, 1);
63 }
64 #endif
65 
66 void
flush_cache_all_local(void)67 flush_cache_all_local(void)
68 {
69 	flush_instruction_cache_local(NULL);
70 	flush_data_cache_local(NULL);
71 }
72 EXPORT_SYMBOL(flush_cache_all_local);
73 
74 /* Virtual address of pfn.  */
75 #define pfn_va(pfn)	__va(PFN_PHYS(pfn))
76 
77 void
update_mmu_cache(struct vm_area_struct * vma,unsigned long address,pte_t * ptep)78 update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *ptep)
79 {
80 	unsigned long pfn = pte_pfn(*ptep);
81 	struct page *page;
82 
83 	/* We don't have pte special.  As a result, we can be called with
84 	   an invalid pfn and we don't need to flush the kernel dcache page.
85 	   This occurs with FireGL card in C8000.  */
86 	if (!pfn_valid(pfn))
87 		return;
88 
89 	page = pfn_to_page(pfn);
90 	if (page_mapping(page) && test_bit(PG_dcache_dirty, &page->flags)) {
91 		flush_kernel_dcache_page_addr(pfn_va(pfn));
92 		clear_bit(PG_dcache_dirty, &page->flags);
93 	} else if (parisc_requires_coherency())
94 		flush_kernel_dcache_page_addr(pfn_va(pfn));
95 }
96 
97 void
show_cache_info(struct seq_file * m)98 show_cache_info(struct seq_file *m)
99 {
100 	char buf[32];
101 
102 	seq_printf(m, "I-cache\t\t: %ld KB\n",
103 		cache_info.ic_size/1024 );
104 	if (cache_info.dc_loop != 1)
105 		snprintf(buf, 32, "%lu-way associative", cache_info.dc_loop);
106 	seq_printf(m, "D-cache\t\t: %ld KB (%s%s, %s)\n",
107 		cache_info.dc_size/1024,
108 		(cache_info.dc_conf.cc_wt ? "WT":"WB"),
109 		(cache_info.dc_conf.cc_sh ? ", shared I/D":""),
110 		((cache_info.dc_loop == 1) ? "direct mapped" : buf));
111 	seq_printf(m, "ITLB entries\t: %ld\n" "DTLB entries\t: %ld%s\n",
112 		cache_info.it_size,
113 		cache_info.dt_size,
114 		cache_info.dt_conf.tc_sh ? " - shared with ITLB":""
115 	);
116 
117 #ifndef CONFIG_PA20
118 	/* BTLB - Block TLB */
119 	if (btlb_info.max_size==0) {
120 		seq_printf(m, "BTLB\t\t: not supported\n" );
121 	} else {
122 		seq_printf(m,
123 		"BTLB fixed\t: max. %d pages, pagesize=%d (%dMB)\n"
124 		"BTLB fix-entr.\t: %d instruction, %d data (%d combined)\n"
125 		"BTLB var-entr.\t: %d instruction, %d data (%d combined)\n",
126 		btlb_info.max_size, (int)4096,
127 		btlb_info.max_size>>8,
128 		btlb_info.fixed_range_info.num_i,
129 		btlb_info.fixed_range_info.num_d,
130 		btlb_info.fixed_range_info.num_comb,
131 		btlb_info.variable_range_info.num_i,
132 		btlb_info.variable_range_info.num_d,
133 		btlb_info.variable_range_info.num_comb
134 		);
135 	}
136 #endif
137 }
138 
139 void __init
parisc_cache_init(void)140 parisc_cache_init(void)
141 {
142 	if (pdc_cache_info(&cache_info) < 0)
143 		panic("parisc_cache_init: pdc_cache_info failed");
144 
145 #if 0
146 	printk("ic_size %lx dc_size %lx it_size %lx\n",
147 		cache_info.ic_size,
148 		cache_info.dc_size,
149 		cache_info.it_size);
150 
151 	printk("DC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
152 		cache_info.dc_base,
153 		cache_info.dc_stride,
154 		cache_info.dc_count,
155 		cache_info.dc_loop);
156 
157 	printk("dc_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
158 		*(unsigned long *) (&cache_info.dc_conf),
159 		cache_info.dc_conf.cc_alias,
160 		cache_info.dc_conf.cc_block,
161 		cache_info.dc_conf.cc_line,
162 		cache_info.dc_conf.cc_shift);
163 	printk("	wt %d sh %d cst %d hv %d\n",
164 		cache_info.dc_conf.cc_wt,
165 		cache_info.dc_conf.cc_sh,
166 		cache_info.dc_conf.cc_cst,
167 		cache_info.dc_conf.cc_hv);
168 
169 	printk("IC  base 0x%lx stride 0x%lx count 0x%lx loop 0x%lx\n",
170 		cache_info.ic_base,
171 		cache_info.ic_stride,
172 		cache_info.ic_count,
173 		cache_info.ic_loop);
174 
175 	printk("ic_conf = 0x%lx  alias %d blk %d line %d shift %d\n",
176 		*(unsigned long *) (&cache_info.ic_conf),
177 		cache_info.ic_conf.cc_alias,
178 		cache_info.ic_conf.cc_block,
179 		cache_info.ic_conf.cc_line,
180 		cache_info.ic_conf.cc_shift);
181 	printk("	wt %d sh %d cst %d hv %d\n",
182 		cache_info.ic_conf.cc_wt,
183 		cache_info.ic_conf.cc_sh,
184 		cache_info.ic_conf.cc_cst,
185 		cache_info.ic_conf.cc_hv);
186 
187 	printk("D-TLB conf: sh %d page %d cst %d aid %d pad1 %d\n",
188 		cache_info.dt_conf.tc_sh,
189 		cache_info.dt_conf.tc_page,
190 		cache_info.dt_conf.tc_cst,
191 		cache_info.dt_conf.tc_aid,
192 		cache_info.dt_conf.tc_pad1);
193 
194 	printk("I-TLB conf: sh %d page %d cst %d aid %d pad1 %d\n",
195 		cache_info.it_conf.tc_sh,
196 		cache_info.it_conf.tc_page,
197 		cache_info.it_conf.tc_cst,
198 		cache_info.it_conf.tc_aid,
199 		cache_info.it_conf.tc_pad1);
200 #endif
201 
202 	split_tlb = 0;
203 	if (cache_info.dt_conf.tc_sh == 0 || cache_info.dt_conf.tc_sh == 2) {
204 		if (cache_info.dt_conf.tc_sh == 2)
205 			printk(KERN_WARNING "Unexpected TLB configuration. "
206 			"Will flush I/D separately (could be optimized).\n");
207 
208 		split_tlb = 1;
209 	}
210 
211 	/* "New and Improved" version from Jim Hull
212 	 *	(1 << (cc_block-1)) * (cc_line << (4 + cnf.cc_shift))
213 	 * The following CAFL_STRIDE is an optimized version, see
214 	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023625.html
215 	 * http://lists.parisc-linux.org/pipermail/parisc-linux/2004-June/023671.html
216 	 */
217 #define CAFL_STRIDE(cnf) (cnf.cc_line << (3 + cnf.cc_block + cnf.cc_shift))
218 	dcache_stride = CAFL_STRIDE(cache_info.dc_conf);
219 	icache_stride = CAFL_STRIDE(cache_info.ic_conf);
220 #undef CAFL_STRIDE
221 
222 #ifndef CONFIG_PA20
223 	if (pdc_btlb_info(&btlb_info) < 0) {
224 		memset(&btlb_info, 0, sizeof btlb_info);
225 	}
226 #endif
227 
228 	if ((boot_cpu_data.pdc.capabilities & PDC_MODEL_NVA_MASK) ==
229 						PDC_MODEL_NVA_UNSUPPORTED) {
230 		printk(KERN_WARNING "parisc_cache_init: Only equivalent aliasing supported!\n");
231 #if 0
232 		panic("SMP kernel required to avoid non-equivalent aliasing");
233 #endif
234 	}
235 }
236 
disable_sr_hashing(void)237 void disable_sr_hashing(void)
238 {
239 	int srhash_type, retval;
240 	unsigned long space_bits;
241 
242 	switch (boot_cpu_data.cpu_type) {
243 	case pcx: /* We shouldn't get this far.  setup.c should prevent it. */
244 		BUG();
245 		return;
246 
247 	case pcxs:
248 	case pcxt:
249 	case pcxt_:
250 		srhash_type = SRHASH_PCXST;
251 		break;
252 
253 	case pcxl:
254 		srhash_type = SRHASH_PCXL;
255 		break;
256 
257 	case pcxl2: /* pcxl2 doesn't support space register hashing */
258 		return;
259 
260 	default: /* Currently all PA2.0 machines use the same ins. sequence */
261 		srhash_type = SRHASH_PA20;
262 		break;
263 	}
264 
265 	disable_sr_hashing_asm(srhash_type);
266 
267 	retval = pdc_spaceid_bits(&space_bits);
268 	/* If this procedure isn't implemented, don't panic. */
269 	if (retval < 0 && retval != PDC_BAD_OPTION)
270 		panic("pdc_spaceid_bits call failed.\n");
271 	if (space_bits != 0)
272 		panic("SpaceID hashing is still on!\n");
273 }
274 
275 static inline void
__flush_cache_page(struct vm_area_struct * vma,unsigned long vmaddr,unsigned long physaddr)276 __flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr,
277 		   unsigned long physaddr)
278 {
279 	preempt_disable();
280 	flush_dcache_page_asm(physaddr, vmaddr);
281 	if (vma->vm_flags & VM_EXEC)
282 		flush_icache_page_asm(physaddr, vmaddr);
283 	preempt_enable();
284 }
285 
flush_dcache_page(struct page * page)286 void flush_dcache_page(struct page *page)
287 {
288 	struct address_space *mapping = page_mapping(page);
289 	struct vm_area_struct *mpnt;
290 	unsigned long offset;
291 	unsigned long addr, old_addr = 0;
292 	pgoff_t pgoff;
293 
294 	if (mapping && !mapping_mapped(mapping)) {
295 		set_bit(PG_dcache_dirty, &page->flags);
296 		return;
297 	}
298 
299 	flush_kernel_dcache_page(page);
300 
301 	if (!mapping)
302 		return;
303 
304 	pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
305 
306 	/* We have carefully arranged in arch_get_unmapped_area() that
307 	 * *any* mappings of a file are always congruently mapped (whether
308 	 * declared as MAP_PRIVATE or MAP_SHARED), so we only need
309 	 * to flush one address here for them all to become coherent */
310 
311 	flush_dcache_mmap_lock(mapping);
312 	vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) {
313 		offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT;
314 		addr = mpnt->vm_start + offset;
315 
316 		/* The TLB is the engine of coherence on parisc: The
317 		 * CPU is entitled to speculate any page with a TLB
318 		 * mapping, so here we kill the mapping then flush the
319 		 * page along a special flush only alias mapping.
320 		 * This guarantees that the page is no-longer in the
321 		 * cache for any process and nor may it be
322 		 * speculatively read in (until the user or kernel
323 		 * specifically accesses it, of course) */
324 
325 		flush_tlb_page(mpnt, addr);
326 		if (old_addr == 0 || (old_addr & (SHM_COLOUR - 1))
327 				      != (addr & (SHM_COLOUR - 1))) {
328 			__flush_cache_page(mpnt, addr, page_to_phys(page));
329 			if (old_addr)
330 				printk(KERN_ERR "INEQUIVALENT ALIASES 0x%lx and 0x%lx in file %s\n", old_addr, addr, mpnt->vm_file ? (char *)mpnt->vm_file->f_path.dentry->d_name.name : "(null)");
331 			old_addr = addr;
332 		}
333 	}
334 	flush_dcache_mmap_unlock(mapping);
335 }
336 EXPORT_SYMBOL(flush_dcache_page);
337 
338 /* Defined in arch/parisc/kernel/pacache.S */
339 EXPORT_SYMBOL(flush_kernel_dcache_range_asm);
340 EXPORT_SYMBOL(flush_kernel_dcache_page_asm);
341 EXPORT_SYMBOL(flush_data_cache_local);
342 EXPORT_SYMBOL(flush_kernel_icache_range_asm);
343 
344 #define FLUSH_THRESHOLD 0x80000 /* 0.5MB */
345 static unsigned long parisc_cache_flush_threshold __read_mostly = FLUSH_THRESHOLD;
346 
347 #define FLUSH_TLB_THRESHOLD (2*1024*1024) /* 2MB initial TLB threshold */
348 static unsigned long parisc_tlb_flush_threshold __read_mostly = FLUSH_TLB_THRESHOLD;
349 
parisc_setup_cache_timing(void)350 void __init parisc_setup_cache_timing(void)
351 {
352 	unsigned long rangetime, alltime;
353 	unsigned long size, start;
354 	unsigned long threshold;
355 
356 	alltime = mfctl(16);
357 	flush_data_cache();
358 	alltime = mfctl(16) - alltime;
359 
360 	size = (unsigned long)(_end - _text);
361 	rangetime = mfctl(16);
362 	flush_kernel_dcache_range((unsigned long)_text, size);
363 	rangetime = mfctl(16) - rangetime;
364 
365 	printk(KERN_DEBUG "Whole cache flush %lu cycles, flushing %lu bytes %lu cycles\n",
366 		alltime, size, rangetime);
367 
368 	threshold = L1_CACHE_ALIGN(size * alltime / rangetime);
369 	if (threshold > cache_info.dc_size)
370 		threshold = cache_info.dc_size;
371 	if (threshold)
372 		parisc_cache_flush_threshold = threshold;
373 	printk(KERN_INFO "Cache flush threshold set to %lu KiB\n",
374 		parisc_cache_flush_threshold/1024);
375 
376 	/* calculate TLB flush threshold */
377 
378 	/* On SMP machines, skip the TLB measure of kernel text which
379 	 * has been mapped as huge pages. */
380 	if (num_online_cpus() > 1 && !parisc_requires_coherency()) {
381 		threshold = max(cache_info.it_size, cache_info.dt_size);
382 		threshold *= PAGE_SIZE;
383 		threshold /= num_online_cpus();
384 		goto set_tlb_threshold;
385 	}
386 
387 	alltime = mfctl(16);
388 	flush_tlb_all();
389 	alltime = mfctl(16) - alltime;
390 
391 	size = 0;
392 	start = (unsigned long) _text;
393 	rangetime = mfctl(16);
394 	while (start < (unsigned long) _end) {
395 		flush_tlb_kernel_range(start, start + PAGE_SIZE);
396 		start += PAGE_SIZE;
397 		size += PAGE_SIZE;
398 	}
399 	rangetime = mfctl(16) - rangetime;
400 
401 	printk(KERN_DEBUG "Whole TLB flush %lu cycles, flushing %lu bytes %lu cycles\n",
402 		alltime, size, rangetime);
403 
404 	threshold = PAGE_ALIGN(num_online_cpus() * size * alltime / rangetime);
405 
406 set_tlb_threshold:
407 	if (threshold)
408 		parisc_tlb_flush_threshold = threshold;
409 	printk(KERN_INFO "TLB flush threshold set to %lu KiB\n",
410 		parisc_tlb_flush_threshold/1024);
411 }
412 
413 extern void purge_kernel_dcache_page_asm(unsigned long);
414 extern void clear_user_page_asm(void *, unsigned long);
415 extern void copy_user_page_asm(void *, void *, unsigned long);
416 
flush_kernel_dcache_page_addr(void * addr)417 void flush_kernel_dcache_page_addr(void *addr)
418 {
419 	unsigned long flags;
420 
421 	flush_kernel_dcache_page_asm(addr);
422 	purge_tlb_start(flags);
423 	pdtlb_kernel(addr);
424 	purge_tlb_end(flags);
425 }
426 EXPORT_SYMBOL(flush_kernel_dcache_page_addr);
427 
copy_user_page(void * vto,void * vfrom,unsigned long vaddr,struct page * pg)428 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
429 	struct page *pg)
430 {
431        /* Copy using kernel mapping.  No coherency is needed (all in
432 	  kunmap) for the `to' page.  However, the `from' page needs to
433 	  be flushed through a mapping equivalent to the user mapping
434 	  before it can be accessed through the kernel mapping. */
435 	preempt_disable();
436 	flush_dcache_page_asm(__pa(vfrom), vaddr);
437 	preempt_enable();
438 	copy_page_asm(vto, vfrom);
439 }
440 EXPORT_SYMBOL(copy_user_page);
441 
442 /* __flush_tlb_range()
443  *
444  * returns 1 if all TLBs were flushed.
445  */
__flush_tlb_range(unsigned long sid,unsigned long start,unsigned long end)446 int __flush_tlb_range(unsigned long sid, unsigned long start,
447 		      unsigned long end)
448 {
449 	unsigned long flags, size;
450 
451 	size = (end - start);
452 	if (size >= parisc_tlb_flush_threshold) {
453 		flush_tlb_all();
454 		return 1;
455 	}
456 
457 	/* Purge TLB entries for small ranges using the pdtlb and
458 	   pitlb instructions.  These instructions execute locally
459 	   but cause a purge request to be broadcast to other TLBs.  */
460 	if (likely(!split_tlb)) {
461 		while (start < end) {
462 			purge_tlb_start(flags);
463 			mtsp(sid, 1);
464 			pdtlb(start);
465 			purge_tlb_end(flags);
466 			start += PAGE_SIZE;
467 		}
468 		return 0;
469 	}
470 
471 	/* split TLB case */
472 	while (start < end) {
473 		purge_tlb_start(flags);
474 		mtsp(sid, 1);
475 		pdtlb(start);
476 		pitlb(start);
477 		purge_tlb_end(flags);
478 		start += PAGE_SIZE;
479 	}
480 	return 0;
481 }
482 
cacheflush_h_tmp_function(void * dummy)483 static void cacheflush_h_tmp_function(void *dummy)
484 {
485 	flush_cache_all_local();
486 }
487 
flush_cache_all(void)488 void flush_cache_all(void)
489 {
490 	on_each_cpu(cacheflush_h_tmp_function, NULL, 1);
491 }
492 
mm_total_size(struct mm_struct * mm)493 static inline unsigned long mm_total_size(struct mm_struct *mm)
494 {
495 	struct vm_area_struct *vma;
496 	unsigned long usize = 0;
497 
498 	for (vma = mm->mmap; vma; vma = vma->vm_next)
499 		usize += vma->vm_end - vma->vm_start;
500 	return usize;
501 }
502 
get_ptep(pgd_t * pgd,unsigned long addr)503 static inline pte_t *get_ptep(pgd_t *pgd, unsigned long addr)
504 {
505 	pte_t *ptep = NULL;
506 
507 	if (!pgd_none(*pgd)) {
508 		pud_t *pud = pud_offset(pgd, addr);
509 		if (!pud_none(*pud)) {
510 			pmd_t *pmd = pmd_offset(pud, addr);
511 			if (!pmd_none(*pmd))
512 				ptep = pte_offset_map(pmd, addr);
513 		}
514 	}
515 	return ptep;
516 }
517 
flush_cache_mm(struct mm_struct * mm)518 void flush_cache_mm(struct mm_struct *mm)
519 {
520 	struct vm_area_struct *vma;
521 	pgd_t *pgd;
522 
523 	/* Flushing the whole cache on each cpu takes forever on
524 	   rp3440, etc.  So, avoid it if the mm isn't too big.  */
525 	if (mm_total_size(mm) >= parisc_cache_flush_threshold) {
526 		flush_cache_all();
527 		return;
528 	}
529 
530 	if (mm->context == mfsp(3)) {
531 		for (vma = mm->mmap; vma; vma = vma->vm_next) {
532 			flush_user_dcache_range_asm(vma->vm_start, vma->vm_end);
533 			if ((vma->vm_flags & VM_EXEC) == 0)
534 				continue;
535 			flush_user_icache_range_asm(vma->vm_start, vma->vm_end);
536 		}
537 		return;
538 	}
539 
540 	pgd = mm->pgd;
541 	for (vma = mm->mmap; vma; vma = vma->vm_next) {
542 		unsigned long addr;
543 
544 		for (addr = vma->vm_start; addr < vma->vm_end;
545 		     addr += PAGE_SIZE) {
546 			unsigned long pfn;
547 			pte_t *ptep = get_ptep(pgd, addr);
548 			if (!ptep)
549 				continue;
550 			pfn = pte_pfn(*ptep);
551 			if (!pfn_valid(pfn))
552 				continue;
553 			__flush_cache_page(vma, addr, PFN_PHYS(pfn));
554 		}
555 	}
556 }
557 
558 void
flush_user_dcache_range(unsigned long start,unsigned long end)559 flush_user_dcache_range(unsigned long start, unsigned long end)
560 {
561 	if ((end - start) < parisc_cache_flush_threshold)
562 		flush_user_dcache_range_asm(start,end);
563 	else
564 		flush_data_cache();
565 }
566 
567 void
flush_user_icache_range(unsigned long start,unsigned long end)568 flush_user_icache_range(unsigned long start, unsigned long end)
569 {
570 	if ((end - start) < parisc_cache_flush_threshold)
571 		flush_user_icache_range_asm(start,end);
572 	else
573 		flush_instruction_cache();
574 }
575 
flush_cache_range(struct vm_area_struct * vma,unsigned long start,unsigned long end)576 void flush_cache_range(struct vm_area_struct *vma,
577 		unsigned long start, unsigned long end)
578 {
579 	unsigned long addr;
580 	pgd_t *pgd;
581 
582 	BUG_ON(!vma->vm_mm->context);
583 
584 	if ((end - start) >= parisc_cache_flush_threshold) {
585 		flush_cache_all();
586 		return;
587 	}
588 
589 	if (vma->vm_mm->context == mfsp(3)) {
590 		flush_user_dcache_range_asm(start, end);
591 		if (vma->vm_flags & VM_EXEC)
592 			flush_user_icache_range_asm(start, end);
593 		return;
594 	}
595 
596 	pgd = vma->vm_mm->pgd;
597 	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
598 		unsigned long pfn;
599 		pte_t *ptep = get_ptep(pgd, addr);
600 		if (!ptep)
601 			continue;
602 		pfn = pte_pfn(*ptep);
603 		if (pfn_valid(pfn))
604 			__flush_cache_page(vma, addr, PFN_PHYS(pfn));
605 	}
606 }
607 
608 void
flush_cache_page(struct vm_area_struct * vma,unsigned long vmaddr,unsigned long pfn)609 flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long pfn)
610 {
611 	BUG_ON(!vma->vm_mm->context);
612 
613 	if (pfn_valid(pfn)) {
614 		flush_tlb_page(vma, vmaddr);
615 		__flush_cache_page(vma, vmaddr, PFN_PHYS(pfn));
616 	}
617 }
618