Linux Kernel  3.7.1
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cache.c
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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) 1994 - 2003, 06, 07 by Ralf Baechle ([email protected])
7  * Copyright (C) 2007 MIPS Technologies, Inc.
8  */
9 #include <linux/fs.h>
10 #include <linux/fcntl.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/linkage.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 #include <linux/syscalls.h>
17 #include <linux/mm.h>
18 
19 #include <asm/cacheflush.h>
20 #include <asm/processor.h>
21 #include <asm/cpu.h>
22 #include <asm/cpu-features.h>
23 
24 /* Cache operations. */
27 void (*flush_cache_mm)(struct mm_struct *mm);
28 void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start,
29  unsigned long end);
30 void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page,
31  unsigned long pfn);
32 void (*flush_icache_range)(unsigned long start, unsigned long end);
33 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
34 
37 
38 void (*__flush_kernel_vmap_range)(unsigned long vaddr, int size);
40 
42 
43 /* MIPS specific cache operations */
44 void (*flush_cache_sigtramp)(unsigned long addr);
46 void (*flush_data_cache_page)(unsigned long addr);
48 
51 
52 #ifdef CONFIG_DMA_NONCOHERENT
53 
54 /* DMA cache operations. */
55 void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
56 void (*_dma_cache_wback)(unsigned long start, unsigned long size);
57 void (*_dma_cache_inv)(unsigned long start, unsigned long size);
58 
59 EXPORT_SYMBOL(_dma_cache_wback_inv);
60 
61 #endif /* CONFIG_DMA_NONCOHERENT */
62 
63 /*
64  * We could optimize the case where the cache argument is not BCACHE but
65  * that seems very atypical use ...
66  */
67 SYSCALL_DEFINE3(cacheflush, unsigned long, addr, unsigned long, bytes,
68  unsigned int, cache)
69 {
70  if (bytes == 0)
71  return 0;
72  if (!access_ok(VERIFY_WRITE, (void __user *) addr, bytes))
73  return -EFAULT;
74 
76 
77  return 0;
78 }
79 
81 {
82  struct address_space *mapping = page_mapping(page);
83  unsigned long addr;
84 
85  if (PageHighMem(page))
86  return;
87  if (mapping && !mapping_mapped(mapping)) {
88  SetPageDcacheDirty(page);
89  return;
90  }
91 
92  /*
93  * We could delay the flush for the !page_mapping case too. But that
94  * case is for exec env/arg pages and those are %99 certainly going to
95  * get faulted into the tlb (and thus flushed) anyways.
96  */
97  addr = (unsigned long) page_address(page);
99 }
100 
102 
103 void __flush_anon_page(struct page *page, unsigned long vmaddr)
104 {
105  unsigned long addr = (unsigned long) page_address(page);
106 
107  if (pages_do_alias(addr, vmaddr)) {
108  if (page_mapped(page) && !Page_dcache_dirty(page)) {
109  void *kaddr;
110 
111  kaddr = kmap_coherent(page, vmaddr);
112  flush_data_cache_page((unsigned long)kaddr);
113  kunmap_coherent();
114  } else
115  flush_data_cache_page(addr);
116  }
117 }
118 
120 
121 void __update_cache(struct vm_area_struct *vma, unsigned long address,
122  pte_t pte)
123 {
124  struct page *page;
125  unsigned long pfn, addr;
126  int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc;
127 
128  pfn = pte_pfn(pte);
129  if (unlikely(!pfn_valid(pfn)))
130  return;
131  page = pfn_to_page(pfn);
132  if (page_mapping(page) && Page_dcache_dirty(page)) {
133  addr = (unsigned long) page_address(page);
134  if (exec || pages_do_alias(addr, address & PAGE_MASK))
135  flush_data_cache_page(addr);
136  ClearPageDcacheDirty(page);
137  }
138 }
139 
142 
143 static inline void setup_protection_map(void)
144 {
145  if (cpu_has_rixi) {
154 
163 
164  } else {
181  }
182 }
183 
185 {
186  if (cpu_has_3k_cache) {
187  extern void __weak r3k_cache_init(void);
188 
189  r3k_cache_init();
190  }
191  if (cpu_has_6k_cache) {
192  extern void __weak r6k_cache_init(void);
193 
194  r6k_cache_init();
195  }
196  if (cpu_has_4k_cache) {
197  extern void __weak r4k_cache_init(void);
198 
199  r4k_cache_init();
200  }
201  if (cpu_has_8k_cache) {
202  extern void __weak r8k_cache_init(void);
203 
204  r8k_cache_init();
205  }
206  if (cpu_has_tx39_cache) {
207  extern void __weak tx39_cache_init(void);
208 
209  tx39_cache_init();
210  }
211 
212  if (cpu_has_octeon_cache) {
213  extern void __weak octeon_cache_init(void);
214 
216  }
217 
218  setup_protection_map();
219 }
220 
221 int __weak __uncached_access(struct file *file, unsigned long addr)
222 {
223  if (file->f_flags & O_DSYNC)
224  return 1;
225 
226  return addr >= __pa(high_memory);
227 }