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            (1U << 0)
   8 #define EXTENT_WRITEBACK        (1U << 1)
   9 #define EXTENT_UPTODATE         (1U << 2)
  10 #define EXTENT_LOCKED           (1U << 3)
  11 #define EXTENT_NEW              (1U << 4)
  12 #define EXTENT_DELALLOC         (1U << 5)
  13 #define EXTENT_DEFRAG           (1U << 6)
  14 #define EXTENT_BOUNDARY         (1U << 9)
  15 #define EXTENT_NODATASUM        (1U << 10)
  16 #define EXTENT_DO_ACCOUNTING    (1U << 11)
  17 #define EXTENT_FIRST_DELALLOC   (1U << 12)
  18 #define EXTENT_NEED_WAIT        (1U << 13)
  19 #define EXTENT_DAMAGED          (1U << 14)
  20 #define EXTENT_NORESERVE        (1U << 15)
  21 #define EXTENT_IOBITS           (EXTENT_LOCKED | EXTENT_WRITEBACK)
  22 #define EXTENT_CTLBITS          (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
  23
  24 /*
  25  * flags for bio submission. The high bits indicate the compression
  26  * type for this bio
  27  */
  28 #define EXTENT_BIO_COMPRESSED 1
  29 #define EXTENT_BIO_TREE_LOG 2
  30 #define EXTENT_BIO_PARENT_LOCKED 4
  31 #define EXTENT_BIO_FLAG_SHIFT 16
  32
  33 /* these are bit numbers for test/set bit */
  34 #define EXTENT_BUFFER_UPTODATE 0
  35 #define EXTENT_BUFFER_DIRTY 2
  36 #define EXTENT_BUFFER_CORRUPT 3
  37 #define EXTENT_BUFFER_READAHEAD 4       /* this got triggered by readahead */
  38 #define EXTENT_BUFFER_TREE_REF 5
  39 #define EXTENT_BUFFER_STALE 6
  40 #define EXTENT_BUFFER_WRITEBACK 7
  41 #define EXTENT_BUFFER_READ_ERR 8        /* read IO error */
  42 #define EXTENT_BUFFER_DUMMY 9
  43 #define EXTENT_BUFFER_IN_TREE 10
  44 #define EXTENT_BUFFER_WRITE_ERR 11    /* write IO error */
  45
  46 /* these are flags for extent_clear_unlock_delalloc */
  47 #define PAGE_UNLOCK             (1 << 0)
  48 #define PAGE_CLEAR_DIRTY        (1 << 1)
  49 #define PAGE_SET_WRITEBACK      (1 << 2)
  50 #define PAGE_END_WRITEBACK      (1 << 3)
  51 #define PAGE_SET_PRIVATE2       (1 << 4)
  52 #define PAGE_SET_ERROR          (1 << 5)
  53
  54 /*
  55  * page->private values.  Every page that is controlled by the extent
  56  * map has page->private set to one.
  57  */
  58 #define EXTENT_PAGE_PRIVATE 1
  59
  60 struct extent_state;
  61 struct btrfs_root;
  62 struct btrfs_io_bio;
  63
  64 typedef int (extent_submit_bio_hook_t)(struct inode *inode, int rw,
  65                                        struct bio *bio, int mirror_num,
  66                                        unsigned long bio_flags, u64 bio_offset);
  67 struct extent_io_ops {
  68         int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
  69                              u64 start, u64 end, int *page_started,
  70                              unsigned long *nr_written);
  71         int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
  72         int (*writepage_io_hook)(struct page *page, u64 start, u64 end);
  73         extent_submit_bio_hook_t *submit_bio_hook;
  74         int (*merge_bio_hook)(int rw, struct page *page, unsigned long offset,
  75                               size_t size, struct bio *bio,
  76                               unsigned long bio_flags);
  77         int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
  78         int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
  79                                     struct page *page, u64 start, u64 end,
  80                                     int mirror);
  81         int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
  82                                       struct extent_state *state, int uptodate);
  83         void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
  84                              unsigned *bits);
  85         void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
  86                                unsigned *bits);
  87         void (*merge_extent_hook)(struct inode *inode,
  88                                   struct extent_state *new,
  89                                   struct extent_state *other);
  90         void (*split_extent_hook)(struct inode *inode,
  91                                   struct extent_state *orig, u64 split);
  92 };
  93
  94 struct extent_io_tree {
  95         struct rb_root state;
  96         struct address_space *mapping;
  97         u64 dirty_bytes;
  98         int track_uptodate;
  99         spinlock_t lock;
 100         const struct extent_io_ops *ops;
 101 };
 102
 103 struct extent_state {
 104         u64 start;
 105         u64 end; /* inclusive */
 106         struct rb_node rb_node;
 107
 108         /* ADD NEW ELEMENTS AFTER THIS */
 109         wait_queue_head_t wq;
 110         atomic_t refs;
 111         unsigned state;
 112
 113         /* for use by the FS */
 114         u64 private;
 115
 116 #ifdef CONFIG_BTRFS_DEBUG
 117         struct list_head leak_list;
 118 #endif
 119 };
 120
 121 #define INLINE_EXTENT_BUFFER_PAGES 16
 122 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE)
 123 struct extent_buffer {
 124         u64 start;
 125         unsigned long len;
 126         unsigned long bflags;
 127         struct btrfs_fs_info *fs_info;
 128         spinlock_t refs_lock;
 129         atomic_t refs;
 130         atomic_t io_pages;
 131         int read_mirror;
 132         struct rcu_head rcu_head;
 133         pid_t lock_owner;
 134
 135         /* count of read lock holders on the extent buffer */
 136         atomic_t write_locks;
 137         atomic_t read_locks;
 138         atomic_t blocking_writers;
 139         atomic_t blocking_readers;
 140         atomic_t spinning_readers;
 141         atomic_t spinning_writers;
 142         short lock_nested;
 143         /* >= 0 if eb belongs to a log tree, -1 otherwise */
 144         short log_index;
 145
 146         /* protects write locks */
 147         rwlock_t lock;
 148
 149         /* readers use lock_wq while they wait for the write
 150          * lock holders to unlock
 151          */
 152         wait_queue_head_t write_lock_wq;
 153
 154         /* writers use read_lock_wq while they wait for readers
 155          * to unlock
 156          */
 157         wait_queue_head_t read_lock_wq;
 158         struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
 159 #ifdef CONFIG_BTRFS_DEBUG
 160         struct list_head leak_list;
 161 #endif
 162 };
 163
 164 static inline void extent_set_compress_type(unsigned long *bio_flags,
 165                                             int compress_type)
 166 {
 167         *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
 168 }
 169
 170 static inline int extent_compress_type(unsigned long bio_flags)
 171 {
 172         return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
 173 }
 174
 175 struct extent_map_tree;
 176
 177 typedef struct extent_map *(get_extent_t)(struct inode *inode,
 178                                           struct page *page,
 179                                           size_t pg_offset,
 180                                           u64 start, u64 len,
 181                                           int create);
 182
 183 void extent_io_tree_init(struct extent_io_tree *tree,
 184                          struct address_space *mapping);
 185 int try_release_extent_mapping(struct extent_map_tree *map,
 186                                struct extent_io_tree *tree, struct page *page,
 187                                gfp_t mask);
 188 int try_release_extent_buffer(struct page *page);
 189 int lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
 190 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 191                      unsigned bits, struct extent_state **cached);
 192 int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end);
 193 int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
 194                          struct extent_state **cached, gfp_t mask);
 195 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
 196 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 197                           get_extent_t *get_extent, int mirror_num);
 198 int extent_read_full_page_nolock(struct extent_io_tree *tree, struct page *page,
 199                                  get_extent_t *get_extent, int mirror_num);
 200 int __init extent_io_init(void);
 201 void extent_io_exit(void);
 202
 203 u64 count_range_bits(struct extent_io_tree *tree,
 204                      u64 *start, u64 search_end,
 205                      u64 max_bytes, unsigned bits, int contig);
 206
 207 void free_extent_state(struct extent_state *state);
 208 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 209                    unsigned bits, int filled,
 210                    struct extent_state *cached_state);
 211 int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 212                       unsigned bits, gfp_t mask);
 213 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 214                      unsigned bits, int wake, int delete,
 215                      struct extent_state **cached, gfp_t mask);
 216 int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 217                     unsigned bits, gfp_t mask);
 218 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 219                    unsigned bits, u64 *failed_start,
 220                    struct extent_state **cached_state, gfp_t mask);
 221 int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
 222                         struct extent_state **cached_state, gfp_t mask);
 223 int clear_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
 224                           struct extent_state **cached_state, gfp_t mask);
 225 int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
 226                    gfp_t mask);
 227 int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 228                      gfp_t mask);
 229 int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
 230                        gfp_t mask);
 231 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 232                        unsigned bits, unsigned clear_bits,
 233                        struct extent_state **cached_state, gfp_t mask);
 234 int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
 235                         struct extent_state **cached_state, gfp_t mask);
 236 int set_extent_defrag(struct extent_io_tree *tree, u64 start, u64 end,
 237                       struct extent_state **cached_state, gfp_t mask);
 238 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
 239                           u64 *start_ret, u64 *end_ret, unsigned bits,
 240                           struct extent_state **cached_state);
 241 int extent_invalidatepage(struct extent_io_tree *tree,
 242                           struct page *page, unsigned long offset);
 243 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
 244                           get_extent_t *get_extent,
 245                           struct writeback_control *wbc);
 246 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
 247                               u64 start, u64 end, get_extent_t *get_extent,
 248                               int mode);
 249 int extent_writepages(struct extent_io_tree *tree,
 250                       struct address_space *mapping,
 251                       get_extent_t *get_extent,
 252                       struct writeback_control *wbc);
 253 int btree_write_cache_pages(struct address_space *mapping,
 254                             struct writeback_control *wbc);
 255 int extent_readpages(struct extent_io_tree *tree,
 256                      struct address_space *mapping,
 257                      struct list_head *pages, unsigned nr_pages,
 258                      get_extent_t get_extent);
 259 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 260                 __u64 start, __u64 len, get_extent_t *get_extent);
 261 int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private);
 262 void set_page_extent_mapped(struct page *page);
 263
 264 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 265                                           u64 start);
 266 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 267                 u64 start);
 268 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
 269 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
 270                                          u64 start);
 271 void free_extent_buffer(struct extent_buffer *eb);
 272 void free_extent_buffer_stale(struct extent_buffer *eb);
 273 #define WAIT_NONE       0
 274 #define WAIT_COMPLETE   1
 275 #define WAIT_PAGE_LOCK  2
 276 int read_extent_buffer_pages(struct extent_io_tree *tree,
 277                              struct extent_buffer *eb, u64 start, int wait,
 278                              get_extent_t *get_extent, int mirror_num);
 279 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 280
 281 static inline unsigned long num_extent_pages(u64 start, u64 len)
 282 {
 283         return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
 284                 (start >> PAGE_CACHE_SHIFT);
 285 }
 286
 287 static inline void extent_buffer_get(struct extent_buffer *eb)
 288 {
 289         atomic_inc(&eb->refs);
 290 }
 291
 292 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
 293                           unsigned long start,
 294                           unsigned long len);
 295 void read_extent_buffer(struct extent_buffer *eb, void *dst,
 296                         unsigned long start,
 297                         unsigned long len);
 298 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
 299                                unsigned long start,
 300                                unsigned long len);
 301 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 302                          unsigned long start, unsigned long len);
 303 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 304                         unsigned long dst_offset, unsigned long src_offset,
 305                         unsigned long len);
 306 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 307                            unsigned long src_offset, unsigned long len);
 308 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 309                            unsigned long src_offset, unsigned long len);
 310 void memset_extent_buffer(struct extent_buffer *eb, char c,
 311                           unsigned long start, unsigned long len);
 312 void clear_extent_buffer_dirty(struct extent_buffer *eb);
 313 int set_extent_buffer_dirty(struct extent_buffer *eb);
 314 int set_extent_buffer_uptodate(struct extent_buffer *eb);
 315 int clear_extent_buffer_uptodate(struct extent_buffer *eb);
 316 int extent_buffer_uptodate(struct extent_buffer *eb);
 317 int extent_buffer_under_io(struct extent_buffer *eb);
 318 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 319                       unsigned long min_len, char **map,
 320                       unsigned long *map_start,
 321                       unsigned long *map_len);
 322 int extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
 323 int extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
 324 int extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
 325                                  struct page *locked_page,
 326                                  unsigned bits_to_clear,
 327                                  unsigned long page_ops);
 328 struct bio *
 329 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
 330                 gfp_t gfp_flags);
 331 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
 332 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
 333
 334 struct btrfs_fs_info;
 335
 336 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
 337                       struct page *page, unsigned int pg_offset,
 338                       int mirror_num);
 339 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
 340                      unsigned int pg_offset);
 341 int end_extent_writepage(struct page *page, int err, u64 start, u64 end);
 342 int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
 343                          int mirror_num);
 344
 345 /*
 346  * When IO fails, either with EIO or csum verification fails, we
 347  * try other mirrors that might have a good copy of the data.  This
 348  * io_failure_record is used to record state as we go through all the
 349  * mirrors.  If another mirror has good data, the page is set up to date
 350  * and things continue.  If a good mirror can't be found, the original
 351  * bio end_io callback is called to indicate things have failed.
 352  */
 353 struct io_failure_record {
 354         struct page *page;
 355         u64 start;
 356         u64 len;
 357         u64 logical;
 358         unsigned long bio_flags;
 359         int this_mirror;
 360         int failed_mirror;
 361         int in_validation;
 362 };
 363
 364 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
 365 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
 366                                 struct io_failure_record **failrec_ret);
 367 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
 368                            struct io_failure_record *failrec, int fail_mirror);
 369 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
 370                                     struct io_failure_record *failrec,
 371                                     struct page *page, int pg_offset, int icsum,
 372                                     bio_end_io_t *endio_func, void *data);
 373 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
 374 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 375 noinline u64 find_lock_delalloc_range(struct inode *inode,
 376                                       struct extent_io_tree *tree,
 377                                       struct page *locked_page, u64 *start,
 378                                       u64 *end, u64 max_bytes);
 379 #endif
 380 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
 381                                                u64 start);
 382 #endif