This source file includes following definitions.
- clean_bdev_bh_alias
- block_page_mkwrite_return
- attach_page_buffers
- get_bh
- put_bh
- brelse
- bforget
- sb_bread
- sb_bread_unmovable
- sb_breadahead
- sb_breadahead_unmovable
- sb_getblk
- sb_getblk_gfp
- sb_find_get_block
- map_bh
- wait_on_buffer
- trylock_buffer
- lock_buffer
- getblk_unmovable
- __getblk
- __bread
- buffer_init
- try_to_free_buffers
- inode_has_buffers
- invalidate_inode_buffers
- remove_inode_buffers
- sync_mapping_buffers
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7
8 #ifndef _LINUX_BUFFER_HEAD_H
9 #define _LINUX_BUFFER_HEAD_H
10
11 #include <linux/types.h>
12 #include <linux/fs.h>
13 #include <linux/linkage.h>
14 #include <linux/pagemap.h>
15 #include <linux/wait.h>
16 #include <linux/atomic.h>
17
18 #ifdef CONFIG_BLOCK
19
20 enum bh_state_bits {
21 BH_Uptodate,
22 BH_Dirty,
23 BH_Lock,
24 BH_Req,
25 BH_Uptodate_Lock,
26
27
28
29 BH_Mapped,
30 BH_New,
31 BH_Async_Read,
32 BH_Async_Write,
33 BH_Delay,
34 BH_Boundary,
35 BH_Write_EIO,
36 BH_Unwritten,
37 BH_Quiet,
38 BH_Meta,
39 BH_Prio,
40 BH_Defer_Completion,
41
42 BH_PrivateStart,
43
44
45 };
46
47 #define MAX_BUF_PER_PAGE (PAGE_SIZE / 512)
48
49 struct page;
50 struct buffer_head;
51 struct address_space;
52 typedef void (bh_end_io_t)(struct buffer_head *bh, int uptodate);
53
54
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58
59
60
61
62
63 struct buffer_head {
64 unsigned long b_state;
65 struct buffer_head *b_this_page;
66 struct page *b_page;
67
68 sector_t b_blocknr;
69 size_t b_size;
70 char *b_data;
71
72 struct block_device *b_bdev;
73 bh_end_io_t *b_end_io;
74 void *b_private;
75 struct list_head b_assoc_buffers;
76 struct address_space *b_assoc_map;
77
78 atomic_t b_count;
79 };
80
81
82
83
84
85
86
87 #define BUFFER_FNS(bit, name) \
88 static __always_inline void set_buffer_##name(struct buffer_head *bh) \
89 { \
90 if (!test_bit(BH_##bit, &(bh)->b_state)) \
91 set_bit(BH_##bit, &(bh)->b_state); \
92 } \
93 static __always_inline void clear_buffer_##name(struct buffer_head *bh) \
94 { \
95 clear_bit(BH_##bit, &(bh)->b_state); \
96 } \
97 static __always_inline int buffer_##name(const struct buffer_head *bh) \
98 { \
99 return test_bit(BH_##bit, &(bh)->b_state); \
100 }
101
102
103
104
105 #define TAS_BUFFER_FNS(bit, name) \
106 static __always_inline int test_set_buffer_##name(struct buffer_head *bh) \
107 { \
108 return test_and_set_bit(BH_##bit, &(bh)->b_state); \
109 } \
110 static __always_inline int test_clear_buffer_##name(struct buffer_head *bh) \
111 { \
112 return test_and_clear_bit(BH_##bit, &(bh)->b_state); \
113 } \
114
115
116
117
118
119
120 BUFFER_FNS(Uptodate, uptodate)
121 BUFFER_FNS(Dirty, dirty)
122 TAS_BUFFER_FNS(Dirty, dirty)
123 BUFFER_FNS(Lock, locked)
124 BUFFER_FNS(Req, req)
125 TAS_BUFFER_FNS(Req, req)
126 BUFFER_FNS(Mapped, mapped)
127 BUFFER_FNS(New, new)
128 BUFFER_FNS(Async_Read, async_read)
129 BUFFER_FNS(Async_Write, async_write)
130 BUFFER_FNS(Delay, delay)
131 BUFFER_FNS(Boundary, boundary)
132 BUFFER_FNS(Write_EIO, write_io_error)
133 BUFFER_FNS(Unwritten, unwritten)
134 BUFFER_FNS(Meta, meta)
135 BUFFER_FNS(Prio, prio)
136 BUFFER_FNS(Defer_Completion, defer_completion)
137
138 #define bh_offset(bh) ((unsigned long)(bh)->b_data & ~PAGE_MASK)
139
140
141 #define page_buffers(page) \
142 ({ \
143 BUG_ON(!PagePrivate(page)); \
144 ((struct buffer_head *)page_private(page)); \
145 })
146 #define page_has_buffers(page) PagePrivate(page)
147
148 void buffer_check_dirty_writeback(struct page *page,
149 bool *dirty, bool *writeback);
150
151
152
153
154
155 void mark_buffer_dirty(struct buffer_head *bh);
156 void mark_buffer_write_io_error(struct buffer_head *bh);
157 void touch_buffer(struct buffer_head *bh);
158 void set_bh_page(struct buffer_head *bh,
159 struct page *page, unsigned long offset);
160 int try_to_free_buffers(struct page *);
161 struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
162 bool retry);
163 void create_empty_buffers(struct page *, unsigned long,
164 unsigned long b_state);
165 void end_buffer_read_sync(struct buffer_head *bh, int uptodate);
166 void end_buffer_write_sync(struct buffer_head *bh, int uptodate);
167 void end_buffer_async_write(struct buffer_head *bh, int uptodate);
168
169
170 void mark_buffer_dirty_inode(struct buffer_head *bh, struct inode *inode);
171 int inode_has_buffers(struct inode *);
172 void invalidate_inode_buffers(struct inode *);
173 int remove_inode_buffers(struct inode *inode);
174 int sync_mapping_buffers(struct address_space *mapping);
175 void clean_bdev_aliases(struct block_device *bdev, sector_t block,
176 sector_t len);
177 static inline void clean_bdev_bh_alias(struct buffer_head *bh)
178 {
179 clean_bdev_aliases(bh->b_bdev, bh->b_blocknr, 1);
180 }
181
182 void mark_buffer_async_write(struct buffer_head *bh);
183 void __wait_on_buffer(struct buffer_head *);
184 wait_queue_head_t *bh_waitq_head(struct buffer_head *bh);
185 struct buffer_head *__find_get_block(struct block_device *bdev, sector_t block,
186 unsigned size);
187 struct buffer_head *__getblk_gfp(struct block_device *bdev, sector_t block,
188 unsigned size, gfp_t gfp);
189 void __brelse(struct buffer_head *);
190 void __bforget(struct buffer_head *);
191 void __breadahead(struct block_device *, sector_t block, unsigned int size);
192 void __breadahead_gfp(struct block_device *, sector_t block, unsigned int size,
193 gfp_t gfp);
194 struct buffer_head *__bread_gfp(struct block_device *,
195 sector_t block, unsigned size, gfp_t gfp);
196 void invalidate_bh_lrus(void);
197 struct buffer_head *alloc_buffer_head(gfp_t gfp_flags);
198 void free_buffer_head(struct buffer_head * bh);
199 void unlock_buffer(struct buffer_head *bh);
200 void __lock_buffer(struct buffer_head *bh);
201 void ll_rw_block(int, int, int, struct buffer_head * bh[]);
202 int sync_dirty_buffer(struct buffer_head *bh);
203 int __sync_dirty_buffer(struct buffer_head *bh, int op_flags);
204 void write_dirty_buffer(struct buffer_head *bh, int op_flags);
205 int submit_bh(int, int, struct buffer_head *);
206 void write_boundary_block(struct block_device *bdev,
207 sector_t bblock, unsigned blocksize);
208 int bh_uptodate_or_lock(struct buffer_head *bh);
209 int bh_submit_read(struct buffer_head *bh);
210
211 extern int buffer_heads_over_limit;
212
213
214
215
216
217 void block_invalidatepage(struct page *page, unsigned int offset,
218 unsigned int length);
219 int block_write_full_page(struct page *page, get_block_t *get_block,
220 struct writeback_control *wbc);
221 int __block_write_full_page(struct inode *inode, struct page *page,
222 get_block_t *get_block, struct writeback_control *wbc,
223 bh_end_io_t *handler);
224 int block_read_full_page(struct page*, get_block_t*);
225 int block_is_partially_uptodate(struct page *page, unsigned long from,
226 unsigned long count);
227 int block_write_begin(struct address_space *mapping, loff_t pos, unsigned len,
228 unsigned flags, struct page **pagep, get_block_t *get_block);
229 int __block_write_begin(struct page *page, loff_t pos, unsigned len,
230 get_block_t *get_block);
231 int block_write_end(struct file *, struct address_space *,
232 loff_t, unsigned, unsigned,
233 struct page *, void *);
234 int generic_write_end(struct file *, struct address_space *,
235 loff_t, unsigned, unsigned,
236 struct page *, void *);
237 void page_zero_new_buffers(struct page *page, unsigned from, unsigned to);
238 void clean_page_buffers(struct page *page);
239 int cont_write_begin(struct file *, struct address_space *, loff_t,
240 unsigned, unsigned, struct page **, void **,
241 get_block_t *, loff_t *);
242 int generic_cont_expand_simple(struct inode *inode, loff_t size);
243 int block_commit_write(struct page *page, unsigned from, unsigned to);
244 int block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
245 get_block_t get_block);
246
247 static inline vm_fault_t block_page_mkwrite_return(int err)
248 {
249 if (err == 0)
250 return VM_FAULT_LOCKED;
251 if (err == -EFAULT || err == -EAGAIN)
252 return VM_FAULT_NOPAGE;
253 if (err == -ENOMEM)
254 return VM_FAULT_OOM;
255
256 return VM_FAULT_SIGBUS;
257 }
258 sector_t generic_block_bmap(struct address_space *, sector_t, get_block_t *);
259 int block_truncate_page(struct address_space *, loff_t, get_block_t *);
260 int nobh_write_begin(struct address_space *, loff_t, unsigned, unsigned,
261 struct page **, void **, get_block_t*);
262 int nobh_write_end(struct file *, struct address_space *,
263 loff_t, unsigned, unsigned,
264 struct page *, void *);
265 int nobh_truncate_page(struct address_space *, loff_t, get_block_t *);
266 int nobh_writepage(struct page *page, get_block_t *get_block,
267 struct writeback_control *wbc);
268
269 void buffer_init(void);
270
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273
274
275 static inline void attach_page_buffers(struct page *page,
276 struct buffer_head *head)
277 {
278 get_page(page);
279 SetPagePrivate(page);
280 set_page_private(page, (unsigned long)head);
281 }
282
283 static inline void get_bh(struct buffer_head *bh)
284 {
285 atomic_inc(&bh->b_count);
286 }
287
288 static inline void put_bh(struct buffer_head *bh)
289 {
290 smp_mb__before_atomic();
291 atomic_dec(&bh->b_count);
292 }
293
294 static inline void brelse(struct buffer_head *bh)
295 {
296 if (bh)
297 __brelse(bh);
298 }
299
300 static inline void bforget(struct buffer_head *bh)
301 {
302 if (bh)
303 __bforget(bh);
304 }
305
306 static inline struct buffer_head *
307 sb_bread(struct super_block *sb, sector_t block)
308 {
309 return __bread_gfp(sb->s_bdev, block, sb->s_blocksize, __GFP_MOVABLE);
310 }
311
312 static inline struct buffer_head *
313 sb_bread_unmovable(struct super_block *sb, sector_t block)
314 {
315 return __bread_gfp(sb->s_bdev, block, sb->s_blocksize, 0);
316 }
317
318 static inline void
319 sb_breadahead(struct super_block *sb, sector_t block)
320 {
321 __breadahead(sb->s_bdev, block, sb->s_blocksize);
322 }
323
324 static inline void
325 sb_breadahead_unmovable(struct super_block *sb, sector_t block)
326 {
327 __breadahead_gfp(sb->s_bdev, block, sb->s_blocksize, 0);
328 }
329
330 static inline struct buffer_head *
331 sb_getblk(struct super_block *sb, sector_t block)
332 {
333 return __getblk_gfp(sb->s_bdev, block, sb->s_blocksize, __GFP_MOVABLE);
334 }
335
336
337 static inline struct buffer_head *
338 sb_getblk_gfp(struct super_block *sb, sector_t block, gfp_t gfp)
339 {
340 return __getblk_gfp(sb->s_bdev, block, sb->s_blocksize, gfp);
341 }
342
343 static inline struct buffer_head *
344 sb_find_get_block(struct super_block *sb, sector_t block)
345 {
346 return __find_get_block(sb->s_bdev, block, sb->s_blocksize);
347 }
348
349 static inline void
350 map_bh(struct buffer_head *bh, struct super_block *sb, sector_t block)
351 {
352 set_buffer_mapped(bh);
353 bh->b_bdev = sb->s_bdev;
354 bh->b_blocknr = block;
355 bh->b_size = sb->s_blocksize;
356 }
357
358 static inline void wait_on_buffer(struct buffer_head *bh)
359 {
360 might_sleep();
361 if (buffer_locked(bh))
362 __wait_on_buffer(bh);
363 }
364
365 static inline int trylock_buffer(struct buffer_head *bh)
366 {
367 return likely(!test_and_set_bit_lock(BH_Lock, &bh->b_state));
368 }
369
370 static inline void lock_buffer(struct buffer_head *bh)
371 {
372 might_sleep();
373 if (!trylock_buffer(bh))
374 __lock_buffer(bh);
375 }
376
377 static inline struct buffer_head *getblk_unmovable(struct block_device *bdev,
378 sector_t block,
379 unsigned size)
380 {
381 return __getblk_gfp(bdev, block, size, 0);
382 }
383
384 static inline struct buffer_head *__getblk(struct block_device *bdev,
385 sector_t block,
386 unsigned size)
387 {
388 return __getblk_gfp(bdev, block, size, __GFP_MOVABLE);
389 }
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399
400
401 static inline struct buffer_head *
402 __bread(struct block_device *bdev, sector_t block, unsigned size)
403 {
404 return __bread_gfp(bdev, block, size, __GFP_MOVABLE);
405 }
406
407 extern int __set_page_dirty_buffers(struct page *page);
408
409 #else
410
411 static inline void buffer_init(void) {}
412 static inline int try_to_free_buffers(struct page *page) { return 1; }
413 static inline int inode_has_buffers(struct inode *inode) { return 0; }
414 static inline void invalidate_inode_buffers(struct inode *inode) {}
415 static inline int remove_inode_buffers(struct inode *inode) { return 1; }
416 static inline int sync_mapping_buffers(struct address_space *mapping) { return 0; }
417
418 #endif
419 #endif