fs/btrfs/extent_io.h

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