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_CLEAR_DATA_RESV  (1U << 17)
  24 #define EXTENT_IOBITS           (EXTENT_LOCKED | EXTENT_WRITEBACK)
  25 #define EXTENT_CTLBITS          (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
  26
  27 /*
  28  * flags for bio submission. The high bits indicate the compression
  29  * type for this bio
  30  */
  31 #define EXTENT_BIO_COMPRESSED 1
  32 #define EXTENT_BIO_TREE_LOG 2
  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 /*
  63  * The extent buffer bitmap operations are done with byte granularity instead of
  64  * word granularity for two reasons:
  65  * 1. The bitmaps must be little-endian on disk.
  66  * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
  67  *    single word in a bitmap may straddle two pages in the extent buffer.
  68  */
  69 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
  70 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
  71 #define BITMAP_FIRST_BYTE_MASK(start) \
  72         ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
  73 #define BITMAP_LAST_BYTE_MASK(nbits) \
  74         (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
  75
  76 static inline int le_test_bit(int nr, const u8 *addr)
  77 {
  78         return 1U & (addr[BIT_BYTE(nr)] >> (nr & (BITS_PER_BYTE-1)));
  79 }
  80
  81 extern void le_bitmap_set(u8 *map, unsigned int start, int len);
  82 extern void le_bitmap_clear(u8 *map, unsigned int start, int len);
  83
  84 struct extent_state;
  85 struct btrfs_root;
  86 struct btrfs_io_bio;
  87 struct io_failure_record;
  88
  89 typedef int (extent_submit_bio_hook_t)(struct inode *inode, struct bio *bio,
  90                                        int mirror_num, unsigned long bio_flags,
  91                                        u64 bio_offset);
  92 struct extent_io_ops {
  93         int (*fill_delalloc)(struct inode *inode, struct page *locked_page,
  94                              u64 start, u64 end, int *page_started,
  95                              unsigned long *nr_written);
  96         int (*writepage_start_hook)(struct page *page, u64 start, u64 end);
  97         extent_submit_bio_hook_t *submit_bio_hook;
  98         int (*merge_bio_hook)(struct page *page, unsigned long offset,
  99                               size_t size, struct bio *bio,
 100                               unsigned long bio_flags);
 101         int (*readpage_io_failed_hook)(struct page *page, int failed_mirror);
 102         int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
 103                                     struct page *page, u64 start, u64 end,
 104                                     int mirror);
 105         int (*writepage_end_io_hook)(struct page *page, u64 start, u64 end,
 106                                       struct extent_state *state, int uptodate);
 107         void (*set_bit_hook)(struct inode *inode, struct extent_state *state,
 108                              unsigned *bits);
 109         void (*clear_bit_hook)(struct inode *inode, struct extent_state *state,
 110                                unsigned *bits);
 111         void (*merge_extent_hook)(struct inode *inode,
 112                                   struct extent_state *new,
 113                                   struct extent_state *other);
 114         void (*split_extent_hook)(struct inode *inode,
 115                                   struct extent_state *orig, u64 split);
 116 };
 117
 118 struct extent_io_tree {
 119         struct rb_root state;
 120         struct address_space *mapping;
 121         u64 dirty_bytes;
 122         int track_uptodate;
 123         spinlock_t lock;
 124         const struct extent_io_ops *ops;
 125 };
 126
 127 struct extent_state {
 128         u64 start;
 129         u64 end; /* inclusive */
 130         struct rb_node rb_node;
 131
 132         /* ADD NEW ELEMENTS AFTER THIS */
 133         wait_queue_head_t wq;
 134         atomic_t refs;
 135         unsigned state;
 136
 137         struct io_failure_record *failrec;
 138
 139 #ifdef CONFIG_BTRFS_DEBUG
 140         struct list_head leak_list;
 141 #endif
 142 };
 143
 144 #define INLINE_EXTENT_BUFFER_PAGES 16
 145 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
 146 struct extent_buffer {
 147         u64 start;
 148         unsigned long len;
 149         unsigned long bflags;
 150         struct btrfs_fs_info *fs_info;
 151         spinlock_t refs_lock;
 152         atomic_t refs;
 153         atomic_t io_pages;
 154         int read_mirror;
 155         struct rcu_head rcu_head;
 156         pid_t lock_owner;
 157
 158         /* count of read lock holders on the extent buffer */
 159         atomic_t write_locks;
 160         atomic_t read_locks;
 161         atomic_t blocking_writers;
 162         atomic_t blocking_readers;
 163         atomic_t spinning_readers;
 164         atomic_t spinning_writers;
 165         short lock_nested;
 166         /* >= 0 if eb belongs to a log tree, -1 otherwise */
 167         short log_index;
 168
 169         /* protects write locks */
 170         rwlock_t lock;
 171
 172         /* readers use lock_wq while they wait for the write
 173          * lock holders to unlock
 174          */
 175         wait_queue_head_t write_lock_wq;
 176
 177         /* writers use read_lock_wq while they wait for readers
 178          * to unlock
 179          */
 180         wait_queue_head_t read_lock_wq;
 181         struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
 182 #ifdef CONFIG_BTRFS_DEBUG
 183         struct list_head leak_list;
 184 #endif
 185 };
 186
 187 /*
 188  * Structure to record how many bytes and which ranges are set/cleared
 189  */
 190 struct extent_changeset {
 191         /* How many bytes are set/cleared in this operation */
 192         u64 bytes_changed;
 193
 194         /* Changed ranges */
 195         struct ulist *range_changed;
 196 };
 197
 198 static inline void extent_set_compress_type(unsigned long *bio_flags,
 199                                             int compress_type)
 200 {
 201         *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
 202 }
 203
 204 static inline int extent_compress_type(unsigned long bio_flags)
 205 {
 206         return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
 207 }
 208
 209 struct extent_map_tree;
 210
 211 typedef struct extent_map *(get_extent_t)(struct inode *inode,
 212                                           struct page *page,
 213                                           size_t pg_offset,
 214                                           u64 start, u64 len,
 215                                           int create);
 216
 217 void extent_io_tree_init(struct extent_io_tree *tree,
 218                          struct address_space *mapping);
 219 int try_release_extent_mapping(struct extent_map_tree *map,
 220                                struct extent_io_tree *tree, struct page *page,
 221                                gfp_t mask);
 222 int try_release_extent_buffer(struct page *page);
 223 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 224                      struct extent_state **cached);
 225
 226 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
 227 {
 228         return lock_extent_bits(tree, start, end, NULL);
 229 }
 230
 231 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
 232 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 233                           get_extent_t *get_extent, int mirror_num);
 234 int __init extent_io_init(void);
 235 void extent_io_exit(void);
 236
 237 u64 count_range_bits(struct extent_io_tree *tree,
 238                      u64 *start, u64 search_end,
 239                      u64 max_bytes, unsigned bits, int contig);
 240
 241 void free_extent_state(struct extent_state *state);
 242 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 243                    unsigned bits, int filled,
 244                    struct extent_state *cached_state);
 245 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 246                 unsigned bits, struct extent_changeset *changeset);
 247 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 248                      unsigned bits, int wake, int delete,
 249                      struct extent_state **cached, gfp_t mask);
 250
 251 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
 252 {
 253         return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
 254                                 GFP_NOFS);
 255 }
 256
 257 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
 258                 u64 end, struct extent_state **cached, gfp_t mask)
 259 {
 260         return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
 261                                 mask);
 262 }
 263
 264 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
 265                 u64 end, unsigned bits)
 266 {
 267         int wake = 0;
 268
 269         if (bits & EXTENT_LOCKED)
 270                 wake = 1;
 271
 272         return clear_extent_bit(tree, start, end, bits, wake, 0, NULL,
 273                         GFP_NOFS);
 274 }
 275
 276 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 277                            unsigned bits, struct extent_changeset *changeset);
 278 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 279                    unsigned bits, u64 *failed_start,
 280                    struct extent_state **cached_state, gfp_t mask);
 281
 282 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
 283                 u64 end, unsigned bits)
 284 {
 285         return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
 286 }
 287
 288 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
 289                 u64 end, struct extent_state **cached_state, gfp_t mask)
 290 {
 291         return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
 292                                 cached_state, mask);
 293 }
 294
 295 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
 296                 u64 end, gfp_t mask)
 297 {
 298         return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
 299                               NULL, mask);
 300 }
 301
 302 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
 303                 u64 end)
 304 {
 305         return clear_extent_bit(tree, start, end,
 306                                 EXTENT_DIRTY | EXTENT_DELALLOC |
 307                                 EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS);
 308 }
 309
 310 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 311                        unsigned bits, unsigned clear_bits,
 312                        struct extent_state **cached_state);
 313
 314 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
 315                 u64 end, struct extent_state **cached_state)
 316 {
 317         return set_extent_bit(tree, start, end,
 318                               EXTENT_DELALLOC | EXTENT_UPTODATE,
 319                               NULL, cached_state, GFP_NOFS);
 320 }
 321
 322 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
 323                 u64 end, struct extent_state **cached_state)
 324 {
 325         return set_extent_bit(tree, start, end,
 326                               EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
 327                               NULL, cached_state, GFP_NOFS);
 328 }
 329
 330 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
 331                 u64 end)
 332 {
 333         return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
 334                         GFP_NOFS);
 335 }
 336
 337 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
 338                 u64 end, struct extent_state **cached_state, gfp_t mask)
 339 {
 340         return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
 341                               cached_state, mask);
 342 }
 343
 344 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
 345                           u64 *start_ret, u64 *end_ret, unsigned bits,
 346                           struct extent_state **cached_state);
 347 int extent_invalidatepage(struct extent_io_tree *tree,
 348                           struct page *page, unsigned long offset);
 349 int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
 350                           get_extent_t *get_extent,
 351                           struct writeback_control *wbc);
 352 int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
 353                               u64 start, u64 end, get_extent_t *get_extent,
 354                               int mode);
 355 int extent_writepages(struct extent_io_tree *tree,
 356                       struct address_space *mapping,
 357                       get_extent_t *get_extent,
 358                       struct writeback_control *wbc);
 359 int btree_write_cache_pages(struct address_space *mapping,
 360                             struct writeback_control *wbc);
 361 int extent_readpages(struct extent_io_tree *tree,
 362                      struct address_space *mapping,
 363                      struct list_head *pages, unsigned nr_pages,
 364                      get_extent_t get_extent);
 365 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 366                 __u64 start, __u64 len, get_extent_t *get_extent);
 367 void set_page_extent_mapped(struct page *page);
 368
 369 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 370                                           u64 start);
 371 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 372                                                   u64 start, unsigned long len);
 373 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 374                                                 u64 start);
 375 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
 376 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
 377                                          u64 start);
 378 void free_extent_buffer(struct extent_buffer *eb);
 379 void free_extent_buffer_stale(struct extent_buffer *eb);
 380 #define WAIT_NONE       0
 381 #define WAIT_COMPLETE   1
 382 #define WAIT_PAGE_LOCK  2
 383 int read_extent_buffer_pages(struct extent_io_tree *tree,
 384                              struct extent_buffer *eb, int wait,
 385                              get_extent_t *get_extent, int mirror_num);
 386 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 387
 388 static inline unsigned long num_extent_pages(u64 start, u64 len)
 389 {
 390         return ((start + len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
 391                 (start >> PAGE_SHIFT);
 392 }
 393
 394 static inline void extent_buffer_get(struct extent_buffer *eb)
 395 {
 396         atomic_inc(&eb->refs);
 397 }
 398
 399 int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
 400                           unsigned long start,
 401                           unsigned long len);
 402 void read_extent_buffer(struct extent_buffer *eb, void *dst,
 403                         unsigned long start,
 404                         unsigned long len);
 405 int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dst,
 406                                unsigned long start,
 407                                unsigned long len);
 408 void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
 409 void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
 410                 const void *src);
 411 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 412                          unsigned long start, unsigned long len);
 413 void copy_extent_buffer_full(struct extent_buffer *dst,
 414                              struct extent_buffer *src);
 415 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 416                         unsigned long dst_offset, unsigned long src_offset,
 417                         unsigned long len);
 418 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 419                            unsigned long src_offset, unsigned long len);
 420 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 421                            unsigned long src_offset, unsigned long len);
 422 void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
 423                            unsigned long len);
 424 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
 425                            unsigned long pos);
 426 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
 427                               unsigned long pos, unsigned long len);
 428 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
 429                                 unsigned long pos, unsigned long len);
 430 void clear_extent_buffer_dirty(struct extent_buffer *eb);
 431 int set_extent_buffer_dirty(struct extent_buffer *eb);
 432 void set_extent_buffer_uptodate(struct extent_buffer *eb);
 433 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
 434 int extent_buffer_uptodate(struct extent_buffer *eb);
 435 int extent_buffer_under_io(struct extent_buffer *eb);
 436 int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset,
 437                       unsigned long min_len, char **map,
 438                       unsigned long *map_start,
 439                       unsigned long *map_len);
 440 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
 441 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
 442 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
 443                                  u64 delalloc_end, struct page *locked_page,
 444                                  unsigned bits_to_clear,
 445                                  unsigned long page_ops);
 446 struct bio *
 447 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
 448                 gfp_t gfp_flags);
 449 struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
 450 struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
 451
 452 struct btrfs_fs_info;
 453
 454 int repair_io_failure(struct inode *inode, u64 start, u64 length, u64 logical,
 455                       struct page *page, unsigned int pg_offset,
 456                       int mirror_num);
 457 int clean_io_failure(struct inode *inode, u64 start, struct page *page,
 458                      unsigned int pg_offset);
 459 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
 460 int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
 461                          struct extent_buffer *eb, int mirror_num);
 462
 463 /*
 464  * When IO fails, either with EIO or csum verification fails, we
 465  * try other mirrors that might have a good copy of the data.  This
 466  * io_failure_record is used to record state as we go through all the
 467  * mirrors.  If another mirror has good data, the page is set up to date
 468  * and things continue.  If a good mirror can't be found, the original
 469  * bio end_io callback is called to indicate things have failed.
 470  */
 471 struct io_failure_record {
 472         struct page *page;
 473         u64 start;
 474         u64 len;
 475         u64 logical;
 476         unsigned long bio_flags;
 477         int this_mirror;
 478         int failed_mirror;
 479         int in_validation;
 480 };
 481
 482 void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end);
 483 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
 484                                 struct io_failure_record **failrec_ret);
 485 int btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
 486                            struct io_failure_record *failrec, int fail_mirror);
 487 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
 488                                     struct io_failure_record *failrec,
 489                                     struct page *page, int pg_offset, int icsum,
 490                                     bio_end_io_t *endio_func, void *data);
 491 int free_io_failure(struct inode *inode, struct io_failure_record *rec);
 492 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 493 noinline u64 find_lock_delalloc_range(struct inode *inode,
 494                                       struct extent_io_tree *tree,
 495                                       struct page *locked_page, u64 *start,
 496                                       u64 *end, u64 max_bytes);
 497 #endif
 498 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
 499                                                u64 start);
 500 #endif