fs/btrfs/extent_map.h

   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_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
  21
  22
  23 struct extent_map_ops {
  24         int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);
  25         int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
  26         int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
  27         int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end);
  28         void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end);
  29 };
  30
  31 struct extent_map_tree {
  32         struct rb_root map;
  33         struct rb_root state;
  34         struct address_space *mapping;
  35         rwlock_t lock;
  36         struct extent_map_ops *ops;
  37         spinlock_t lru_lock;
  38         struct list_head buffer_lru;
  39         int lru_size;
  40 };
  41
  42 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
  43 struct extent_map {
  44         u64 start;
  45         u64 end; /* inclusive */
  46         int in_tree;
  47         struct rb_node rb_node;
  48         /* block_start and block_end are in bytes */
  49         u64 block_start;
  50         u64 block_end; /* inclusive */
  51         struct block_device *bdev;
  52         atomic_t refs;
  53 };
  54
  55 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
  56 struct extent_state {
  57         u64 start;
  58         u64 end; /* inclusive */
  59         int in_tree;
  60         struct rb_node rb_node;
  61         wait_queue_head_t wq;
  62         atomic_t refs;
  63         unsigned long state;
  64
  65         /* for use by the FS */
  66         u64 private;
  67
  68         struct list_head list;
  69 };
  70
  71 struct extent_buffer {
  72         u64 start;
  73         unsigned long len;
  74         char *map_token;
  75         char *kaddr;
  76         unsigned long map_start;
  77         unsigned long map_len;
  78         struct page *first_page;
  79         struct list_head lru;
  80         atomic_t refs;
  81         int flags;
  82 };
  83
  84 typedef struct extent_map *(get_extent_t)(struct inode *inode,
  85                                           struct page *page,
  86                                           size_t page_offset,
  87                                           u64 start, u64 end,
  88                                           int create);
  89
  90 void extent_map_tree_init(struct extent_map_tree *tree,
  91                           struct address_space *mapping, gfp_t mask);
  92 void extent_map_tree_cleanup(struct extent_map_tree *tree);
  93 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
  94                                          u64 start, u64 end);
  95 int add_extent_mapping(struct extent_map_tree *tree,
  96                        struct extent_map *em);
  97 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
  98 int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page);
  99 int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
 100 int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
 101 struct extent_map *alloc_extent_map(gfp_t mask);
 102 void free_extent_map(struct extent_map *em);
 103 int extent_read_full_page(struct extent_map_tree *tree, struct page *page,
 104                           get_extent_t *get_extent);
 105 void __init extent_map_init(void);
 106 void __exit extent_map_exit(void);
 107
 108 int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end,
 109                    int bits, int filled);
 110 int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
 111                       int bits, gfp_t mask);
 112 int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
 113                     int bits, gfp_t mask);
 114 int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end,
 115                         gfp_t mask);
 116 int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end,
 117                    gfp_t mask);
 118 int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
 119                      gfp_t mask);
 120 int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
 121                        gfp_t mask);
 122 int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end,
 123                      gfp_t mask);
 124 int find_first_extent_bit(struct extent_map_tree *tree, u64 start,
 125                           u64 *start_ret, u64 *end_ret, int bits);
 126 int extent_invalidatepage(struct extent_map_tree *tree,
 127                           struct page *page, unsigned long offset);
 128 int extent_write_full_page(struct extent_map_tree *tree, struct page *page,
 129                           get_extent_t *get_extent,
 130                           struct writeback_control *wbc);
 131 int extent_prepare_write(struct extent_map_tree *tree,
 132                          struct inode *inode, struct page *page,
 133                          unsigned from, unsigned to, get_extent_t *get_extent);
 134 int extent_commit_write(struct extent_map_tree *tree,
 135                         struct inode *inode, struct page *page,
 136                         unsigned from, unsigned to);
 137 sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
 138                 get_extent_t *get_extent);
 139 int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end);
 140 int set_state_private(struct extent_map_tree *tree, u64 start, u64 private);
 141 int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private);
 142 void set_page_extent_mapped(struct page *page);
 143
 144 struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree,
 145                                           u64 start, unsigned long len,
 146                                           gfp_t mask);
 147 struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree,
 148                                          u64 start, unsigned long len,
 149                                           gfp_t mask);
 150 void free_extent_buffer(struct extent_buffer *eb);
 151 int read_extent_buffer_pages(struct extent_map_tree *tree,
 152                              struct extent_buffer *eb, int wait);
 153
 154 static inline void extent_buffer_get(struct extent_buffer *eb)
 155 {
 156         atomic_inc(&eb->refs);
 157 }
 158
 159 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
 160                           unsigned long start,
 161                           unsigned long len);
 162 void read_extent_buffer(struct extent_buffer *eb, void *dst,
 163                         unsigned long start,
 164                         unsigned long len);
 165 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 166                          unsigned long start, unsigned long len);
 167 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 168                         unsigned long dst_offset, unsigned long src_offset,
 169                         unsigned long len);
 170 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 171                            unsigned long src_offset, unsigned long len);
 172 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 173                            unsigned long src_offset, unsigned long len);
 174 void memset_extent_buffer(struct extent_buffer *eb, char c,
 175                           unsigned long start, unsigned long len);
 176 int wait_on_extent_buffer_writeback(struct extent_map_tree *tree,
 177                                     struct extent_buffer *eb);
 178 int clear_extent_buffer_dirty(struct extent_map_tree *tree,
 179                               struct extent_buffer *eb);
 180 int set_extent_buffer_dirty(struct extent_map_tree *tree,
 181                              struct extent_buffer *eb);
 182 int set_extent_buffer_uptodate(struct extent_map_tree *tree,
 183                                struct extent_buffer *eb);
 184 int extent_buffer_uptodate(struct extent_map_tree *tree,
 185                            struct extent_buffer *eb);
 186 int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 187                       unsigned long min_len, char **token, char **map,
 188                       unsigned long *map_start,
 189                       unsigned long *map_len, int km);
 190 void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
 191 #endif