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_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 __exit 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