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extent_io.h
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1 #ifndef __EXTENTIO__
2 #define __EXTENTIO__
3 
4 #include <linux/rbtree.h>
5 
6 /* bits for the extent state */
7 #define EXTENT_DIRTY 1
8 #define EXTENT_WRITEBACK (1 << 1)
9 #define EXTENT_UPTODATE (1 << 2)
10 #define EXTENT_LOCKED (1 << 3)
11 #define EXTENT_NEW (1 << 4)
12 #define EXTENT_DELALLOC (1 << 5)
13 #define EXTENT_DEFRAG (1 << 6)
14 #define EXTENT_DEFRAG_DONE (1 << 7)
15 #define EXTENT_BUFFER_FILLED (1 << 8)
16 #define EXTENT_BOUNDARY (1 << 9)
17 #define EXTENT_NODATASUM (1 << 10)
18 #define EXTENT_DO_ACCOUNTING (1 << 11)
19 #define EXTENT_FIRST_DELALLOC (1 << 12)
20 #define EXTENT_NEED_WAIT (1 << 13)
21 #define EXTENT_DAMAGED (1 << 14)
22 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
23 #define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
24 
25 /*
26  * flags for bio submission. The high bits indicate the compression
27  * type for this bio
28  */
29 #define EXTENT_BIO_COMPRESSED 1
30 #define EXTENT_BIO_TREE_LOG 2
31 #define EXTENT_BIO_FLAG_SHIFT 16
32 
33 /* these are bit numbers for test/set bit */
34 #define EXTENT_BUFFER_UPTODATE 0
35 #define EXTENT_BUFFER_BLOCKING 1
36 #define EXTENT_BUFFER_DIRTY 2
37 #define EXTENT_BUFFER_CORRUPT 3
38 #define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
39 #define EXTENT_BUFFER_TREE_REF 5
40 #define EXTENT_BUFFER_STALE 6
41 #define EXTENT_BUFFER_WRITEBACK 7
42 #define EXTENT_BUFFER_IOERR 8
43 #define EXTENT_BUFFER_DUMMY 9
44 
45 /* these are flags for extent_clear_unlock_delalloc */
46 #define EXTENT_CLEAR_UNLOCK_PAGE 0x1
47 #define EXTENT_CLEAR_UNLOCK 0x2
48 #define EXTENT_CLEAR_DELALLOC 0x4
49 #define EXTENT_CLEAR_DIRTY 0x8
50 #define EXTENT_SET_WRITEBACK 0x10
51 #define EXTENT_END_WRITEBACK 0x20
52 #define EXTENT_SET_PRIVATE2 0x40
53 #define EXTENT_CLEAR_ACCOUNTING 0x80
54 
55 /*
56  * page->private values. Every page that is controlled by the extent
57  * map has page->private set to one.
58  */
59 #define EXTENT_PAGE_PRIVATE 1
60 #define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
61 
62 struct extent_state;
63 struct btrfs_root;
64 
65 typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
66  struct bio *bio, int mirror_num,
67  unsigned long bio_flags, u64 bio_offset);
68 struct extent_io_ops {
69  int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
70  u64 start, u64 end, int *page_started,
71  unsigned long *nr_written);
72  int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
73  int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
74  extent_submit_bio_hook_t *submit_bio_hook;
75  int (*merge_bio_hook)(struct page *page, unsigned long offset,
76  size_t size, struct bio *bio,
77  unsigned long bio_flags);
78  int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
79  int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
80  int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
81  struct extent_state *state, int mirror);
82  int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
83  struct extent_state *state, int uptodate);
84  void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
85  int *bits);
86  void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
87  int *bits);
88  void (*merge_extent_hook)(struct inode *inode,
89  struct extent_state *new,
90  struct extent_state *other);
91  void (*split_extent_hook)(struct inode *inode,
92  struct extent_state *orig, u64 split);
93  int (*write_cache_pages_lock_hook)(struct page *page, void *data,
94  void (*flush_fn)(void *));
95 };
96 
97 struct extent_io_tree {
98  struct rb_root state;
99  struct radix_tree_root buffer;
100  struct address_space *mapping;
101  u64 dirty_bytes;
102  int track_uptodate;
103  spinlock_t lock;
104  spinlock_t buffer_lock;
105  struct extent_io_ops *ops;
106 };
107 
108 struct extent_state {
109  u64 start;
110  u64 end; /* inclusive */
111  struct rb_node rb_node;
112 
113  /* ADD NEW ELEMENTS AFTER THIS */
114  struct extent_io_tree *tree;
115  wait_queue_head_t wq;
116  atomic_t refs;
117  unsigned long state;
118 
119  /* for use by the FS */
120  u64 private;
121 
122  struct list_head leak_list;
123 };
124 
125 #define INLINE_EXTENT_BUFFER_PAGES 16
126 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
127 struct extent_buffer {
128  u64 start;
129  unsigned long len;
130  unsigned long map_start;
131  unsigned long map_len;
132  unsigned long bflags;
133  struct extent_io_tree *tree;
134  spinlock_t refs_lock;
135  atomic_t refs;
136  atomic_t io_pages;
137  int read_mirror;
138  struct list_head leak_list;
139  struct rcu_head rcu_head;
140  pid_t lock_owner;
141 
142  /* count of read lock holders on the extent buffer */
143  atomic_t write_locks;
144  atomic_t read_locks;
145  atomic_t blocking_writers;
146  atomic_t blocking_readers;
147  atomic_t spinning_readers;
148  atomic_t spinning_writers;
149  int lock_nested;
150 
151  /* protects write locks */
152  rwlock_t lock;
153 
154  /* readers use lock_wq while they wait for the write
155  * lock holders to unlock
156  */
157  wait_queue_head_t write_lock_wq;
158 
159  /* writers use read_lock_wq while they wait for readers
160  * to unlock
161  */
162  wait_queue_head_t read_lock_wq;
163  wait_queue_head_t lock_wq;
164  struct page *inline_pages[INLINE_EXTENT_BUFFER_PAGES];
165  struct page **pages;
166 };
167 
168 static inline void extent_set_compress_type(unsigned long *bio_flags,
169  int compress_type)
170 {
171  *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
172 }
173 
174 static inline int extent_compress_type(unsigned long bio_flags)
175 {
176  return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
177 }
178 
179 struct extent_map_tree;
180 
181 typedef struct extent_map *(get_extent_t)(struct inode *inode,
182  struct page *page,
183  size_t pg_offset,
184  u64 start, u64 len,
185  int create);
186 
187 void extent_io_tree_init(struct extent_io_tree *tree,
188  struct address_space *mapping);
189 int try_release_extent_mapping(struct extent_map_tree *map,
190  struct extent_io_tree *tree, struct page *page,
191  gfp_t mask);
192 int try_release_extent_buffer(struct page *page, gfp_t mask);
193 int try_release_extent_state(struct extent_map_tree *map,
194  struct extent_io_tree *tree, struct page *page,
195  gfp_t mask);
196 int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
197 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
198  int bits, struct extent_state **cached);
199 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
200 int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
201  struct extent_state **cached, gfp_t mask);
202 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
203 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
204  get_extent_t *get_extent, int mirror_num);
205 int __init extent_io_init(void);
206 void extent_io_exit(void);
207 
208 u64 count_range_bits(struct extent_io_tree *tree,
209  u64 *start, u64 search_end,
210  u64 max_bytes, unsigned long bits, int contig);
211 
212 void free_extent_state(struct extent_state *state);
213 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
214  int bits, int filled, struct extent_state *cached_state);
215 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
216  int bits, gfp_t mask);
217 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
218  int bits, int wake, int delete, struct extent_state **cached,
219  gfp_t mask);
220 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
221  int bits, gfp_t mask);
222 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
223  int bits, u64 *failed_start,
224  struct extent_state **cached_state, gfp_t mask);
225 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
226  struct extent_state **cached_state, gfp_t mask);
227 int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
228  struct extent_state **cached_state, gfp_t mask);
229 int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
230  gfp_t mask);
231 int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
232  gfp_t mask);
233 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
234  gfp_t mask);
235 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
236  int bits, int clear_bits,
237  struct extent_state **cached_state, gfp_t mask);
238 int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
239  struct extent_state **cached_state, gfp_t mask);
240 int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
241  struct extent_state **cached_state, gfp_t mask);
242 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
243  u64 *start_ret, u64 *end_ret, int bits,
244  struct extent_state **cached_state);
245 struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
246  u64 start, int bits);
247 int extent_invalidatepage(struct extent_io_tree *tree,
248  struct page *page, unsigned long offset);
249 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
250  get_extent_t *get_extent,
251  struct writeback_control *wbc);
252 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
253  u64 start, u64 end, get_extent_t *get_extent,
254  int mode);
255 int extent_writepages(struct extent_io_tree *tree,
256  struct address_space *mapping,
257  get_extent_t *get_extent,
258  struct writeback_control *wbc);
259 int btree_write_cache_pages(struct address_space *mapping,
260  struct writeback_control *wbc);
261 int extent_readpages(struct extent_io_tree *tree,
262  struct address_space *mapping,
263  struct list_head *pages, unsigned nr_pages,
264  get_extent_t get_extent);
265 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
266  __u64 start, __u64 len, get_extent_t *get_extent);
267 int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
268 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
269 void set_page_extent_mapped(struct page *page);
270 
271 struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
272  u64 start, unsigned long len);
273 struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len);
274 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
275 struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
276  u64 start, unsigned long len);
277 void free_extent_buffer(struct extent_buffer *eb);
278 void free_extent_buffer_stale(struct extent_buffer *eb);
279 #define WAIT_NONE 0
280 #define WAIT_COMPLETE 1
281 #define WAIT_PAGE_LOCK 2
282 int read_extent_buffer_pages(struct extent_io_tree *tree,
283  struct extent_buffer *eb, u64 start, int wait,
284  get_extent_t *get_extent, int mirror_num);
285 
286 static inline unsigned long num_extent_pages(u64 start, u64 len)
287 {
288  return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
289  (start >> PAGE_CACHE_SHIFT);
290 }
291 
292 static inline struct page *extent_buffer_page(struct extent_buffer *eb,
293  unsigned long i)
294 {
295  return eb->pages[i];
296 }
297 
298 static inline void extent_buffer_get(struct extent_buffer *eb)
299 {
300  atomic_inc(&eb->refs);
301 }
302 
303 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
304  unsigned long start,
305  unsigned long len);
306 void read_extent_buffer(struct extent_buffer *eb, void *dst,
307  unsigned long start,
308  unsigned long len);
309 void write_extent_buffer(struct extent_buffer *eb, const void *src,
310  unsigned long start, unsigned long len);
311 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
312  unsigned long dst_offset, unsigned long src_offset,
313  unsigned long len);
314 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
315  unsigned long src_offset, unsigned long len);
316 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
317  unsigned long src_offset, unsigned long len);
318 void memset_extent_buffer(struct extent_buffer *eb, char c,
319  unsigned long start, unsigned long len);
320 void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits);
321 void clear_extent_buffer_dirty(struct extent_buffer *eb);
322 int set_extent_buffer_dirty(struct extent_buffer *eb);
323 int set_extent_buffer_uptodate(struct extent_buffer *eb);
324 int clear_extent_buffer_uptodate(struct extent_buffer *eb);
325 int extent_buffer_uptodate(struct extent_buffer *eb);
326 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
327  unsigned long min_len, char **map,
328  unsigned long *map_start,
329  unsigned long *map_len);
330 int extent_range_uptodate(struct extent_io_tree *tree,
331  u64 start, u64 end);
332 int extent_clear_unlock_delalloc(struct inode *inode,
333  struct extent_io_tree *tree,
334  u64 start, u64 end, struct page *locked_page,
335  unsigned long op);
336 struct bio *
337 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
338  gfp_t gfp_flags);
339 
340 struct btrfs_mapping_tree;
341 
342 int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
343  u64 length, u64 logical, struct page *page,
344  int mirror_num);
345 int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
346 int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
347  int mirror_num);
348 #endif
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