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         rwlock_t lock;
  44         struct extent_map_ops *ops;
  45         spinlock_t lru_lock;
  46         struct list_head buffer_lru;
  47         int lru_size;
  48 };
  49
  50 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
  51 struct extent_map {
  52         u64 start;
  53         u64 end; /* inclusive */
  54         int in_tree;
  55         struct rb_node rb_node;
  56         /* block_start and block_end are in bytes */
  57         u64 block_start;
  58         u64 block_end; /* inclusive */
  59         struct block_device *bdev;
  60         atomic_t refs;
  61 };
  62
  63 /* note, this must start with the same fields as fs/extent_map.c:tree_entry */
  64 struct extent_state {
  65         u64 start;
  66         u64 end; /* inclusive */
  67         int in_tree;
  68         struct rb_node rb_node;
  69         wait_queue_head_t wq;
  70         atomic_t refs;
  71         unsigned long state;
  72
  73         /* for use by the FS */
  74         u64 private;
  75
  76         struct list_head list;
  77 };
  78
  79 struct extent_buffer {
  80         u64 start;
  81         unsigned long len;
  82         char *map_token;
  83         char *kaddr;
  84         unsigned long map_start;
  85         unsigned long map_len;
  86         struct page *first_page;
  87         struct list_head lru;
  88         atomic_t refs;
  89         int flags;
  90 };
  91
  92 typedef struct extent_map *(get_extent_t)(struct inode *inode,
  93                                           struct page *page,
  94                                           size_t page_offset,
  95                                           u64 start, u64 end,
  96                                           int create);
  97
  98 void extent_map_tree_init(struct extent_map_tree *tree,
  99                           struct address_space *mapping, gfp_t mask);
 100 void extent_map_tree_empty_lru(struct extent_map_tree *tree);
 101 struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
 102                                          u64 start, u64 end);
 103 int add_extent_mapping(struct extent_map_tree *tree,
 104                        struct extent_map *em);
 105 int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
 106 int try_release_extent_mapping(struct extent_map_tree *tree, struct page *page);
 107 int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
 108 int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask);
 109 struct extent_map *alloc_extent_map(gfp_t mask);
 110 void free_extent_map(struct extent_map *em);
 111 int extent_read_full_page(struct extent_map_tree *tree, struct page *page,
 112                           get_extent_t *get_extent);
 113 void __init extent_map_init(void);
 114 void __exit extent_map_exit(void);
 115
 116 int test_range_bit(struct extent_map_tree *tree, u64 start, u64 end,
 117                    int bits, int filled);
 118 int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
 119                       int bits, gfp_t mask);
 120 int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end,
 121                     int bits, gfp_t mask);
 122 int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end,
 123                         gfp_t mask);
 124 int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end,
 125                    gfp_t mask);
 126 int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
 127                      gfp_t mask);
 128 int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end,
 129                        gfp_t mask);
 130 int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end,
 131                      gfp_t mask);
 132 int find_first_extent_bit(struct extent_map_tree *tree, u64 start,
 133                           u64 *start_ret, u64 *end_ret, int bits);
 134 int extent_invalidatepage(struct extent_map_tree *tree,
 135                           struct page *page, unsigned long offset);
 136 int extent_write_full_page(struct extent_map_tree *tree, struct page *page,
 137                           get_extent_t *get_extent,
 138                           struct writeback_control *wbc);
 139 int extent_prepare_write(struct extent_map_tree *tree,
 140                          struct inode *inode, struct page *page,
 141                          unsigned from, unsigned to, get_extent_t *get_extent);
 142 int extent_commit_write(struct extent_map_tree *tree,
 143                         struct inode *inode, struct page *page,
 144                         unsigned from, unsigned to);
 145 sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
 146                 get_extent_t *get_extent);
 147 int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end);
 148 int set_state_private(struct extent_map_tree *tree, u64 start, u64 private);
 149 int get_state_private(struct extent_map_tree *tree, u64 start, u64 *private);
 150 void set_page_extent_mapped(struct page *page);
 151
 152 struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree,
 153                                           u64 start, unsigned long len,
 154                                           struct page *page0,
 155                                           gfp_t mask);
 156 struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree,
 157                                          u64 start, unsigned long len,
 158                                           gfp_t mask);
 159 void free_extent_buffer(struct extent_buffer *eb);
 160 int read_extent_buffer_pages(struct extent_map_tree *tree,
 161                              struct extent_buffer *eb, u64 start, int wait);
 162
 163 static inline void extent_buffer_get(struct extent_buffer *eb)
 164 {
 165         atomic_inc(&eb->refs);
 166 }
 167
 168 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
 169                           unsigned long start,
 170                           unsigned long len);
 171 void read_extent_buffer(struct extent_buffer *eb, void *dst,
 172                         unsigned long start,
 173                         unsigned long len);
 174 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 175                          unsigned long start, unsigned long len);
 176 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 177                         unsigned long dst_offset, unsigned long src_offset,
 178                         unsigned long len);
 179 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 180                            unsigned long src_offset, unsigned long len);
 181 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 182                            unsigned long src_offset, unsigned long len);
 183 void memset_extent_buffer(struct extent_buffer *eb, char c,
 184                           unsigned long start, unsigned long len);
 185 int wait_on_extent_buffer_writeback(struct extent_map_tree *tree,
 186                                     struct extent_buffer *eb);
 187 int clear_extent_buffer_dirty(struct extent_map_tree *tree,
 188                               struct extent_buffer *eb);
 189 int set_extent_buffer_dirty(struct extent_map_tree *tree,
 190                              struct extent_buffer *eb);
 191 int set_extent_buffer_uptodate(struct extent_map_tree *tree,
 192                                struct extent_buffer *eb);
 193 int extent_buffer_uptodate(struct extent_map_tree *tree,
 194                            struct extent_buffer *eb);
 195 int map_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 196                       unsigned long min_len, char **token, char **map,
 197                       unsigned long *map_start,
 198                       unsigned long *map_len, int km);
 199 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 200                       unsigned long min_len, char **token, char **map,
 201                       unsigned long *map_start,
 202                       unsigned long *map_len, int km);
 203 void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km);
 204 #endif