xref: /openbmc/linux/fs/btrfs/extent_map.h (revision 17636e03f42a1a42fed3834859de4702bd655fd1)
1 #ifndef __EXTENTMAP__
2 #define __EXTENTMAP__
3 
4 #include <linux/rbtree.h>
5 
6 #define EXTENT_MAP_HOLE (u64)-3
7 #define EXTENT_MAP_INLINE (u64)-2
8 #define EXTENT_MAP_DELALLOC (u64)-1
9 
10 /* bits for the extent state */
11 #define EXTENT_DIRTY 1
12 #define EXTENT_WRITEBACK (1 << 1)
13 #define EXTENT_UPTODATE (1 << 2)
14 #define EXTENT_LOCKED (1 << 3)
15 #define EXTENT_NEW (1 << 4)
16 #define EXTENT_DELALLOC (1 << 5)
17 #define EXTENT_DEFRAG (1 << 6)
18 #define EXTENT_DEFRAG_DONE (1 << 7)
19 #define EXTENT_BUFFER_FILLED (1 << 8)
20 #define EXTENT_CSUM (1 << 9)
21 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
22 
23 /*
24  * page->private values.  Every page that is controlled by the extent
25  * map has page->private set to one.
26  */
27 #define EXTENT_PAGE_PRIVATE 1
28 #define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
29 
30 
31 struct extent_map_ops {
32 	int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);
33 	int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
34 	int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
35 	int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end);
36 	void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end);
37 };
38 
39 struct extent_map_tree {
40 	struct rb_root map;
41 	struct rb_root state;
42 	struct address_space *mapping;
43 	u64 dirty_bytes;
44 	rwlock_t lock;
45 	struct extent_map_ops *ops;
46 	spinlock_t lru_lock;
47 	struct list_head buffer_lru;
48 	int lru_size;
49 };
50 
51 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
52 struct extent_map {
53 	u64 start;
54 	u64 end; /* inclusive */
55 	int in_tree;
56 	struct rb_node rb_node;
57 	/* block_start and block_end are in bytes */
58 	u64 block_start;
59 	u64 block_end; /* inclusive */
60 	struct block_device *bdev;
61 	atomic_t refs;
62 };
63 
64 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
65 struct extent_state {
66 	u64 start;
67 	u64 end; /* inclusive */
68 	int in_tree;
69 	struct rb_node rb_node;
70 	wait_queue_head_t wq;
71 	atomic_t refs;
72 	unsigned long state;
73 
74 	/* for use by the FS */
75 	u64 private;
76 
77 	struct list_head list;
78 };
79 
80 struct extent_buffer {
81 	u64 start;
82 	unsigned long len;
83 	char *map_token;
84 	char *kaddr;
85 	unsigned long map_start;
86 	unsigned long map_len;
87 	struct page *first_page;
88 	struct list_head lru;
89 	atomic_t refs;
90 	int flags;
91 };
92 
93 typedef struct extent_map *(get_extent_t)(struct inode *inode,
94 					  struct page *page,
95 					  size_t page_offset,
96 					  u64 start, u64 end,
97 					  int create);
98 
99 void extent_map_tree_init(struct extent_map_tree *tree,
100 			  struct address_space *mapping, gfp_t mask);
101 void extent_map_tree_empty_lru(struct extent_map_tree *tree);
102 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
103 					 u64 start, u64 end);
104 int add_extent_mapping(struct extent_map_tree *tree,
105 		       struct extent_map *em);
106 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
107 int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page);
108 int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
109 int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
110 struct extent_map *alloc_extent_map(gfp_t mask);
111 void free_extent_map(struct extent_map *em);
112 int extent_read_full_page(struct extent_map_tree *tree, struct page *page,
113 			  get_extent_t *get_extent);
114 int __init extent_map_init(void);
115 void extent_map_exit(void);
116 
117 u64 count_range_bits(struct extent_map_tree *tree,
118 		     u64 *start, u64 max_bytes, unsigned long bits);
119 
120 int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end,
121 		   int bits, int filled);
122 int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
123 		      int bits, gfp_t mask);
124 int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
125 		    int bits, gfp_t mask);
126 int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end,
127 			gfp_t mask);
128 int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end,
129 		   gfp_t mask);
130 int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
131 		     gfp_t mask);
132 int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
133 		       gfp_t mask);
134 int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end,
135 		     gfp_t mask);
136 int find_first_extent_bit(struct extent_map_tree *tree, u64 start,
137 			  u64 *start_ret, u64 *end_ret, int bits);
138 int extent_invalidatepage(struct extent_map_tree *tree,
139 			  struct page *page, unsigned long offset);
140 int extent_write_full_page(struct extent_map_tree *tree, struct page *page,
141 			  get_extent_t *get_extent,
142 			  struct writeback_control *wbc);
143 int extent_writepages(struct extent_map_tree *tree,
144 		      struct address_space *mapping,
145 		      get_extent_t *get_extent,
146 		      struct writeback_control *wbc);
147 int extent_readpages(struct extent_map_tree *tree,
148 		     struct address_space *mapping,
149 		     struct list_head *pages, unsigned nr_pages,
150 		     get_extent_t get_extent);
151 int extent_prepare_write(struct extent_map_tree *tree,
152 			 struct inode *inode, struct page *page,
153 			 unsigned from, unsigned to, get_extent_t *get_extent);
154 int extent_commit_write(struct extent_map_tree *tree,
155 			struct inode *inode, struct page *page,
156 			unsigned from, unsigned to);
157 sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
158 		get_extent_t *get_extent);
159 int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end);
160 int set_state_private(struct extent_map_tree *tree, u64 start, u64 private);
161 int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private);
162 void set_page_extent_mapped(struct page *page);
163 
164 struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree,
165 					  u64 start, unsigned long len,
166 					  struct page *page0,
167 					  gfp_t mask);
168 struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree,
169 					 u64 start, unsigned long len,
170 					  gfp_t mask);
171 void free_extent_buffer(struct extent_buffer *eb);
172 int read_extent_buffer_pages(struct extent_map_tree *tree,
173 			     struct extent_buffer *eb, u64 start, int wait);
174 
175 static inline void extent_buffer_get(struct extent_buffer *eb)
176 {
177 	atomic_inc(&eb->refs);
178 }
179 
180 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
181 			  unsigned long start,
182 			  unsigned long len);
183 void read_extent_buffer(struct extent_buffer *eb, void *dst,
184 			unsigned long start,
185 			unsigned long len);
186 void write_extent_buffer(struct extent_buffer *eb, const void *src,
187 			 unsigned long start, unsigned long len);
188 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
189 			unsigned long dst_offset, unsigned long src_offset,
190 			unsigned long len);
191 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
192 			   unsigned long src_offset, unsigned long len);
193 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
194 			   unsigned long src_offset, unsigned long len);
195 void memset_extent_buffer(struct extent_buffer *eb, char c,
196 			  unsigned long start, unsigned long len);
197 int wait_on_extent_buffer_writeback(struct extent_map_tree *tree,
198 				    struct extent_buffer *eb);
199 int clear_extent_buffer_dirty(struct extent_map_tree *tree,
200 			      struct extent_buffer *eb);
201 int set_extent_buffer_dirty(struct extent_map_tree *tree,
202 			     struct extent_buffer *eb);
203 int set_extent_buffer_uptodate(struct extent_map_tree *tree,
204 			       struct extent_buffer *eb);
205 int extent_buffer_uptodate(struct extent_map_tree *tree,
206 			   struct extent_buffer *eb);
207 int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
208 		      unsigned long min_len, char **token, char **map,
209 		      unsigned long *map_start,
210 		      unsigned long *map_len, int km);
211 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
212 		      unsigned long min_len, char **token, char **map,
213 		      unsigned long *map_start,
214 		      unsigned long *map_len, int km);
215 void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
216 #endif
217