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_CSUM (1 << 9)
  17 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
  18
  19 /*
  20  * page->private values.  Every page that is controlled by the extent
  21  * map has page->private set to one.
  22  */
  23 #define EXTENT_PAGE_PRIVATE 1
  24 #define EXTENT_PAGE_PRIVATE_FIRST_PAGE 3
  25
  26 struct extent_state;
  27
  28 struct extent_io_ops {
  29         int (*fill_delalloc)(struct inode *inode, u64 start, u64 end);
  30         int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
  31         int (*submit_bio_hook)(int rw, struct bio *bio);
  32         int (*readpage_io_hook)(struct page *page, u64 start, u64 end);
  33         int (*readpage_end_io_hook)(struct page *page, u64 start, u64 end,
  34                                     struct extent_state *state);
  35         void (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
  36                                       struct extent_state *state);
  37         int (*set_bit_hook)(struct inode *inode, u64 start, u64 end,
  38                             unsigned long old, unsigned long bits);
  39         int (*clear_bit_hook)(struct inode *inode, u64 start, u64 end,
  40                             unsigned long old, unsigned long bits);
  41 };
  42
  43 struct extent_io_tree {
  44         struct rb_root state;
  45         struct address_space *mapping;
  46         u64 dirty_bytes;
  47         spinlock_t lock;
  48         struct extent_io_ops *ops;
  49         spinlock_t lru_lock;
  50         struct list_head buffer_lru;
  51         int lru_size;
  52         struct extent_state *last;
  53 };
  54
  55 struct extent_state {
  56         u64 start;
  57         u64 end; /* inclusive */
  58         struct rb_node rb_node;
  59         struct extent_io_tree *tree;
  60         wait_queue_head_t wq;
  61         atomic_t refs;
  62         unsigned long state;
  63
  64         /* for use by the FS */
  65         u64 private;
  66
  67         struct list_head list;
  68 };
  69
  70 struct extent_buffer {
  71         u64 start;
  72         unsigned long len;
  73         char *map_token;
  74         char *kaddr;
  75         unsigned long map_start;
  76         unsigned long map_len;
  77         struct page *first_page;
  78         struct list_head lru;
  79         atomic_t refs;
  80         int flags;
  81 };
  82
  83 struct extent_map_tree;
  84
  85 static inline struct extent_state *extent_state_next(struct extent_state *state)
  86 {
  87         struct rb_node *node;
  88         node = rb_next(&state->rb_node);
  89         if (!node)
  90                 return NULL;
  91         return rb_entry(node, struct extent_state, rb_node);
  92 }
  93
  94 typedef struct extent_map *(get_extent_t)(struct inode *inode,
  95                                           struct page *page,
  96                                           size_t page_offset,
  97                                           u64 start, u64 len,
  98                                           int create);
  99
 100 void extent_io_tree_init(struct extent_io_tree *tree,
 101                           struct address_space *mapping, gfp_t mask);
 102 void extent_io_tree_empty_lru(struct extent_io_tree *tree);
 103 int try_release_extent_mapping(struct extent_map_tree *map,
 104                                struct extent_io_tree *tree, struct page *page,
 105                                gfp_t mask);
 106 int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
 107 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
 108 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 109                           get_extent_t *get_extent);
 110 int __init extent_io_init(void);
 111 void extent_io_exit(void);
 112
 113 u64 count_range_bits(struct extent_io_tree *tree,
 114                      u64 *start, u64 search_end,
 115                      u64 max_bytes, unsigned long bits);
 116
 117 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 118                    int bits, int filled);
 119 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 120                       int bits, gfp_t mask);
 121 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 122                     int bits, gfp_t mask);
 123 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
 124                         gfp_t mask);
 125 int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
 126                    gfp_t mask);
 127 int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 128                      gfp_t mask);
 129 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 130                        gfp_t mask);
 131 int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
 132                      gfp_t mask);
 133 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
 134                           u64 *start_ret, u64 *end_ret, int bits);
 135 struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
 136                                                  u64 start, int bits);
 137 int extent_invalidatepage(struct extent_io_tree *tree,
 138                           struct page *page, unsigned long offset);
 139 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
 140                           get_extent_t *get_extent,
 141                           struct writeback_control *wbc);
 142 int extent_writepages(struct extent_io_tree *tree,
 143                       struct address_space *mapping,
 144                       get_extent_t *get_extent,
 145                       struct writeback_control *wbc);
 146 int extent_readpages(struct extent_io_tree *tree,
 147                      struct address_space *mapping,
 148                      struct list_head *pages, unsigned nr_pages,
 149                      get_extent_t get_extent);
 150 int extent_prepare_write(struct extent_io_tree *tree,
 151                          struct inode *inode, struct page *page,
 152                          unsigned from, unsigned to, get_extent_t *get_extent);
 153 int extent_commit_write(struct extent_io_tree *tree,
 154                         struct inode *inode, struct page *page,
 155                         unsigned from, unsigned to);
 156 sector_t extent_bmap(struct address_space *mapping, sector_t iblock,
 157                 get_extent_t *get_extent);
 158 int set_range_dirty(struct extent_io_tree *tree, u64 start, u64 end);
 159 int set_state_private(struct extent_io_tree *tree, u64 start, u64 private);
 160 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
 161 void set_page_extent_mapped(struct page *page);
 162
 163 struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
 164                                           u64 start, unsigned long len,
 165                                           struct page *page0,
 166                                           gfp_t mask);
 167 struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
 168                                          u64 start, unsigned long len,
 169                                           gfp_t mask);
 170 void free_extent_buffer(struct extent_buffer *eb);
 171 int read_extent_buffer_pages(struct extent_io_tree *tree,
 172                              struct extent_buffer *eb, u64 start, int wait,
 173                              get_extent_t *get_extent);
 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_io_tree *tree,
 198                                     struct extent_buffer *eb);
 199 int clear_extent_buffer_dirty(struct extent_io_tree *tree,
 200                               struct extent_buffer *eb);
 201 int set_extent_buffer_dirty(struct extent_io_tree *tree,
 202                              struct extent_buffer *eb);
 203 int set_extent_buffer_uptodate(struct extent_io_tree *tree,
 204                                struct extent_buffer *eb);
 205 int extent_buffer_uptodate(struct extent_io_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