Root/fs/btrfs/extent_io.h

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_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
20
21/* flags for bio submission */
22#define EXTENT_BIO_COMPRESSED 1
23
24/* these are bit numbers for test/set bit */
25#define EXTENT_BUFFER_UPTODATE 0
26#define EXTENT_BUFFER_BLOCKING 1
27#define EXTENT_BUFFER_DIRTY 2
28
29/* these are flags for extent_clear_unlock_delalloc */
30#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
31#define EXTENT_CLEAR_UNLOCK 0x2
32#define EXTENT_CLEAR_DELALLOC 0x4
33#define EXTENT_CLEAR_DIRTY 0x8
34#define EXTENT_SET_WRITEBACK 0x10
35#define EXTENT_END_WRITEBACK 0x20
36#define EXTENT_SET_PRIVATE2 0x40
37#define EXTENT_CLEAR_ACCOUNTING 0x80
38
39/*
40 * page->private values. Every page that is controlled by the extent
41 * map has page->private set to one.
42 */
43#define EXTENT_PAGE_PRIVATE 1
44#define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
45
46struct extent_state;
47
48typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
49                       struct bio *bio, int mirror_num,
50                       unsigned long bio_flags);
51struct extent_io_ops {
52    int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
53                 u64 start, u64 end, int *page_started,
54                 unsigned long *nr_written);
55    int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
56    int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
57    extent_submit_bio_hook_t *submit_bio_hook;
58    int (*merge_bio_hook)(struct page *page, unsigned long offset,
59                  size_t size, struct bio *bio,
60                  unsigned long bio_flags);
61    int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
62    int (*readpage_io_failed_hook)(struct bio *bio, struct page *page,
63                       u64 start, u64 end,
64                       struct extent_state *state);
65    int (*writepage_io_failed_hook)(struct bio *bio, struct page *page,
66                    u64 start, u64 end,
67                       struct extent_state *state);
68    int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
69                    struct extent_state *state);
70    int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
71                      struct extent_state *state, int uptodate);
72    int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
73                unsigned long old, unsigned long bits);
74    int (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
75                  unsigned long bits);
76    int (*merge_extent_hook)(struct inode *inode,
77                 struct extent_state *new,
78                 struct extent_state *other);
79    int (*split_extent_hook)(struct inode *inode,
80                 struct extent_state *orig, u64 split);
81    int (*write_cache_pages_lock_hook)(struct page *page);
82};
83
84struct extent_io_tree {
85    struct rb_root state;
86    struct rb_root buffer;
87    struct address_space *mapping;
88    u64 dirty_bytes;
89    spinlock_t lock;
90    spinlock_t buffer_lock;
91    struct extent_io_ops *ops;
92};
93
94struct extent_state {
95    u64 start;
96    u64 end; /* inclusive */
97    struct rb_node rb_node;
98
99    /* ADD NEW ELEMENTS AFTER THIS */
100    struct extent_io_tree *tree;
101    wait_queue_head_t wq;
102    atomic_t refs;
103    unsigned long state;
104    u64 split_start;
105    u64 split_end;
106
107    /* for use by the FS */
108    u64 private;
109
110    struct list_head leak_list;
111};
112
113struct extent_buffer {
114    u64 start;
115    unsigned long len;
116    char *map_token;
117    char *kaddr;
118    unsigned long map_start;
119    unsigned long map_len;
120    struct page *first_page;
121    unsigned long bflags;
122    atomic_t refs;
123    struct list_head leak_list;
124    struct rb_node rb_node;
125
126    /* the spinlock is used to protect most operations */
127    spinlock_t lock;
128
129    /*
130     * when we keep the lock held while blocking, waiters go onto
131     * the wq
132     */
133    wait_queue_head_t lock_wq;
134};
135
136struct extent_map_tree;
137
138static inline struct extent_state *extent_state_next(struct extent_state *state)
139{
140    struct rb_node *node;
141    node = rb_next(&state->rb_node);
142    if (!node)
143        return NULL;
144    return rb_entry(node, struct extent_state, rb_node);
145}
146
147typedef struct extent_map *(get_extent_t)(struct inode *inode,
148                      struct page *page,
149                      size_t page_offset,
150                      u64 start, u64 len,
151                      int create);
152
153void extent_io_tree_init(struct extent_io_tree *tree,
154              struct address_space *mapping, gfp_t mask);
155int try_release_extent_mapping(struct extent_map_tree *map,
156                   struct extent_io_tree *tree, struct page *page,
157                   gfp_t mask);
158int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page);
159int try_release_extent_state(struct extent_map_tree *map,
160                 struct extent_io_tree *tree, struct page *page,
161                 gfp_t mask);
162int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
163int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
164             int bits, struct extent_state **cached, gfp_t mask);
165int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
166int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
167             struct extent_state **cached, gfp_t mask);
168int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
169            gfp_t mask);
170int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
171              get_extent_t *get_extent);
172int __init extent_io_init(void);
173void extent_io_exit(void);
174
175u64 count_range_bits(struct extent_io_tree *tree,
176             u64 *start, u64 search_end,
177             u64 max_bytes, unsigned long bits);
178
179int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
180           int bits, int filled, struct extent_state *cached_state);
181int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
182              int bits, gfp_t mask);
183int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
184             int bits, int wake, int delete, struct extent_state **cached,
185             gfp_t mask);
186int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
187            int bits, gfp_t mask);
188int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
189            gfp_t mask);
190int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
191           gfp_t mask);
192int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
193             gfp_t mask);
194int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
195               gfp_t mask);
196int clear_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end,
197               gfp_t mask);
198int clear_extent_ordered_metadata(struct extent_io_tree *tree, u64 start,
199                  u64 end, gfp_t mask);
200int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
201            struct extent_state **cached_state, gfp_t mask);
202int set_extent_ordered(struct extent_io_tree *tree, u64 start, u64 end,
203             gfp_t mask);
204int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
205              u64 *start_ret, u64 *end_ret, int bits);
206struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
207                         u64 start, int bits);
208int extent_invalidatepage(struct extent_io_tree *tree,
209              struct page *page, unsigned long offset);
210int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
211              get_extent_t *get_extent,
212              struct writeback_control *wbc);
213int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
214                  u64 start, u64 end, get_extent_t *get_extent,
215                  int mode);
216int extent_writepages(struct extent_io_tree *tree,
217              struct address_space *mapping,
218              get_extent_t *get_extent,
219              struct writeback_control *wbc);
220int extent_readpages(struct extent_io_tree *tree,
221             struct address_space *mapping,
222             struct list_head *pages, unsigned nr_pages,
223             get_extent_t get_extent);
224int extent_prepare_write(struct extent_io_tree *tree,
225             struct inode *inode, struct page *page,
226             unsigned from, unsigned to, get_extent_t *get_extent);
227int extent_commit_write(struct extent_io_tree *tree,
228            struct inode *inode, struct page *page,
229            unsigned from, unsigned to);
230sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
231        get_extent_t *get_extent);
232int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
233        __u64 start, __u64 len, get_extent_t *get_extent);
234int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end);
235int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
236int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
237void set_page_extent_mapped(struct page *page);
238
239struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
240                      u64 start, unsigned long len,
241                      struct page *page0,
242                      gfp_t mask);
243struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
244                     u64 start, unsigned long len,
245                      gfp_t mask);
246void free_extent_buffer(struct extent_buffer *eb);
247int read_extent_buffer_pages(struct extent_io_tree *tree,
248                 struct extent_buffer *eb, u64 start, int wait,
249                 get_extent_t *get_extent, int mirror_num);
250
251static inline void extent_buffer_get(struct extent_buffer *eb)
252{
253    atomic_inc(&eb->refs);
254}
255
256int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
257              unsigned long start,
258              unsigned long len);
259void read_extent_buffer(struct extent_buffer *eb, void *dst,
260            unsigned long start,
261            unsigned long len);
262void write_extent_buffer(struct extent_buffer *eb, const void *src,
263             unsigned long start, unsigned long len);
264void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
265            unsigned long dst_offset, unsigned long src_offset,
266            unsigned long len);
267void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
268               unsigned long src_offset, unsigned long len);
269void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
270               unsigned long src_offset, unsigned long len);
271void memset_extent_buffer(struct extent_buffer *eb, char c,
272              unsigned long start, unsigned long len);
273int wait_on_extent_buffer_writeback(struct extent_io_tree *tree,
274                    struct extent_buffer *eb);
275int wait_on_extent_writeback(struct extent_io_tree *tree, u64 start, u64 end);
276int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits);
277int clear_extent_buffer_dirty(struct extent_io_tree *tree,
278                  struct extent_buffer *eb);
279int set_extent_buffer_dirty(struct extent_io_tree *tree,
280                 struct extent_buffer *eb);
281int test_extent_buffer_dirty(struct extent_io_tree *tree,
282                 struct extent_buffer *eb);
283int set_extent_buffer_uptodate(struct extent_io_tree *tree,
284                   struct extent_buffer *eb);
285int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
286                struct extent_buffer *eb,
287                struct extent_state **cached_state);
288int extent_buffer_uptodate(struct extent_io_tree *tree,
289               struct extent_buffer *eb,
290               struct extent_state *cached_state);
291int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
292              unsigned long min_len, char **token, char **map,
293              unsigned long *map_start,
294              unsigned long *map_len, int km);
295int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
296              unsigned long min_len, char **token, char **map,
297              unsigned long *map_start,
298              unsigned long *map_len, int km);
299void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
300int release_extent_buffer_tail_pages(struct extent_buffer *eb);
301int extent_range_uptodate(struct extent_io_tree *tree,
302              u64 start, u64 end);
303int extent_clear_unlock_delalloc(struct inode *inode,
304                struct extent_io_tree *tree,
305                u64 start, u64 end, struct page *locked_page,
306                unsigned long op);
307#endif
308

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