fs/btrfs/extent_io.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 #ifndef BTRFS_EXTENT_IO_H
   4 #define BTRFS_EXTENT_IO_H
   5
   6 #include <linux/rbtree.h>
   7 #include <linux/refcount.h>
   8 #include "ulist.h"
   9
  10 /* bits for the extent state */
  11 #define EXTENT_DIRTY            (1U << 0)
  12 #define EXTENT_WRITEBACK        (1U << 1)
  13 #define EXTENT_UPTODATE         (1U << 2)
  14 #define EXTENT_LOCKED           (1U << 3)
  15 #define EXTENT_NEW              (1U << 4)
  16 #define EXTENT_DELALLOC         (1U << 5)
  17 #define EXTENT_DEFRAG           (1U << 6)
  18 #define EXTENT_BOUNDARY         (1U << 9)
  19 #define EXTENT_NODATASUM        (1U << 10)
  20 #define EXTENT_CLEAR_META_RESV  (1U << 11)
  21 #define EXTENT_FIRST_DELALLOC   (1U << 12)
  22 #define EXTENT_NEED_WAIT        (1U << 13)
  23 #define EXTENT_DAMAGED          (1U << 14)
  24 #define EXTENT_NORESERVE        (1U << 15)
  25 #define EXTENT_QGROUP_RESERVED  (1U << 16)
  26 #define EXTENT_CLEAR_DATA_RESV  (1U << 17)
  27 #define EXTENT_DELALLOC_NEW     (1U << 18)
  28 #define EXTENT_IOBITS           (EXTENT_LOCKED | EXTENT_WRITEBACK)
  29 #define EXTENT_DO_ACCOUNTING    (EXTENT_CLEAR_META_RESV | \
  30                                  EXTENT_CLEAR_DATA_RESV)
  31 #define EXTENT_CTLBITS          (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
  32
  33 /*
  34  * flags for bio submission. The high bits indicate the compression
  35  * type for this bio
  36  */
  37 #define EXTENT_BIO_COMPRESSED 1
  38 #define EXTENT_BIO_FLAG_SHIFT 16
  39
  40 enum {
  41         EXTENT_BUFFER_UPTODATE,
  42         EXTENT_BUFFER_DIRTY,
  43         EXTENT_BUFFER_CORRUPT,
  44         /* this got triggered by readahead */
  45         EXTENT_BUFFER_READAHEAD,
  46         EXTENT_BUFFER_TREE_REF,
  47         EXTENT_BUFFER_STALE,
  48         EXTENT_BUFFER_WRITEBACK,
  49         /* read IO error */
  50         EXTENT_BUFFER_READ_ERR,
  51         EXTENT_BUFFER_UNMAPPED,
  52         EXTENT_BUFFER_IN_TREE,
  53         /* write IO error */
  54         EXTENT_BUFFER_WRITE_ERR,
  55 };
  56
  57 /* these are flags for __process_pages_contig */
  58 #define PAGE_UNLOCK             (1 << 0)
  59 #define PAGE_CLEAR_DIRTY        (1 << 1)
  60 #define PAGE_SET_WRITEBACK      (1 << 2)
  61 #define PAGE_END_WRITEBACK      (1 << 3)
  62 #define PAGE_SET_PRIVATE2       (1 << 4)
  63 #define PAGE_SET_ERROR          (1 << 5)
  64 #define PAGE_LOCK               (1 << 6)
  65
  66 /*
  67  * page->private values.  Every page that is controlled by the extent
  68  * map has page->private set to one.
  69  */
  70 #define EXTENT_PAGE_PRIVATE 1
  71
  72 /*
  73  * The extent buffer bitmap operations are done with byte granularity instead of
  74  * word granularity for two reasons:
  75  * 1. The bitmaps must be little-endian on disk.
  76  * 2. Bitmap items are not guaranteed to be aligned to a word and therefore a
  77  *    single word in a bitmap may straddle two pages in the extent buffer.
  78  */
  79 #define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE)
  80 #define BYTE_MASK ((1 << BITS_PER_BYTE) - 1)
  81 #define BITMAP_FIRST_BYTE_MASK(start) \
  82         ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK)
  83 #define BITMAP_LAST_BYTE_MASK(nbits) \
  84         (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1)))
  85
  86 struct extent_state;
  87 struct btrfs_root;
  88 struct btrfs_inode;
  89 struct btrfs_io_bio;
  90 struct io_failure_record;
  91
  92 typedef blk_status_t (extent_submit_bio_hook_t)(void *private_data, struct bio *bio,
  93                                        int mirror_num, unsigned long bio_flags,
  94                                        u64 bio_offset);
  95
  96 typedef blk_status_t (extent_submit_bio_start_t)(void *private_data,
  97                 struct bio *bio, u64 bio_offset);
  98
  99 struct extent_io_ops {
 100         /*
 101          * The following callbacks must be always defined, the function
 102          * pointer will be called unconditionally.
 103          */
 104         extent_submit_bio_hook_t *submit_bio_hook;
 105         int (*readpage_end_io_hook)(struct btrfs_io_bio *io_bio, u64 phy_offset,
 106                                     struct page *page, u64 start, u64 end,
 107                                     int mirror);
 108 };
 109
 110 struct extent_io_tree {
 111         struct rb_root state;
 112         void *private_data;
 113         u64 dirty_bytes;
 114         int track_uptodate;
 115         spinlock_t lock;
 116         const struct extent_io_ops *ops;
 117 };
 118
 119 struct extent_state {
 120         u64 start;
 121         u64 end; /* inclusive */
 122         struct rb_node rb_node;
 123
 124         /* ADD NEW ELEMENTS AFTER THIS */
 125         wait_queue_head_t wq;
 126         refcount_t refs;
 127         unsigned state;
 128
 129         struct io_failure_record *failrec;
 130
 131 #ifdef CONFIG_BTRFS_DEBUG
 132         struct list_head leak_list;
 133 #endif
 134 };
 135
 136 #define INLINE_EXTENT_BUFFER_PAGES 16
 137 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE)
 138 struct extent_buffer {
 139         u64 start;
 140         unsigned long len;
 141         unsigned long bflags;
 142         struct btrfs_fs_info *fs_info;
 143         spinlock_t refs_lock;
 144         atomic_t refs;
 145         atomic_t io_pages;
 146         int read_mirror;
 147         struct rcu_head rcu_head;
 148         pid_t lock_owner;
 149
 150         /* count of read lock holders on the extent buffer */
 151         atomic_t write_locks;
 152         atomic_t read_locks;
 153         atomic_t blocking_writers;
 154         atomic_t blocking_readers;
 155         atomic_t spinning_readers;
 156         atomic_t spinning_writers;
 157         short lock_nested;
 158         /* >= 0 if eb belongs to a log tree, -1 otherwise */
 159         short log_index;
 160
 161         /* protects write locks */
 162         rwlock_t lock;
 163
 164         /* readers use lock_wq while they wait for the write
 165          * lock holders to unlock
 166          */
 167         wait_queue_head_t write_lock_wq;
 168
 169         /* writers use read_lock_wq while they wait for readers
 170          * to unlock
 171          */
 172         wait_queue_head_t read_lock_wq;
 173         struct page *pages[INLINE_EXTENT_BUFFER_PAGES];
 174 #ifdef CONFIG_BTRFS_DEBUG
 175         struct list_head leak_list;
 176 #endif
 177 };
 178
 179 /*
 180  * Structure to record how many bytes and which ranges are set/cleared
 181  */
 182 struct extent_changeset {
 183         /* How many bytes are set/cleared in this operation */
 184         unsigned int bytes_changed;
 185
 186         /* Changed ranges */
 187         struct ulist range_changed;
 188 };
 189
 190 static inline void extent_changeset_init(struct extent_changeset *changeset)
 191 {
 192         changeset->bytes_changed = 0;
 193         ulist_init(&changeset->range_changed);
 194 }
 195
 196 static inline struct extent_changeset *extent_changeset_alloc(void)
 197 {
 198         struct extent_changeset *ret;
 199
 200         ret = kmalloc(sizeof(*ret), GFP_KERNEL);
 201         if (!ret)
 202                 return NULL;
 203
 204         extent_changeset_init(ret);
 205         return ret;
 206 }
 207
 208 static inline void extent_changeset_release(struct extent_changeset *changeset)
 209 {
 210         if (!changeset)
 211                 return;
 212         changeset->bytes_changed = 0;
 213         ulist_release(&changeset->range_changed);
 214 }
 215
 216 static inline void extent_changeset_free(struct extent_changeset *changeset)
 217 {
 218         if (!changeset)
 219                 return;
 220         extent_changeset_release(changeset);
 221         kfree(changeset);
 222 }
 223
 224 static inline void extent_set_compress_type(unsigned long *bio_flags,
 225                                             int compress_type)
 226 {
 227         *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
 228 }
 229
 230 static inline int extent_compress_type(unsigned long bio_flags)
 231 {
 232         return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
 233 }
 234
 235 struct extent_map_tree;
 236
 237 typedef struct extent_map *(get_extent_t)(struct btrfs_inode *inode,
 238                                           struct page *page,
 239                                           size_t pg_offset,
 240                                           u64 start, u64 len,
 241                                           int create);
 242
 243 void extent_io_tree_init(struct extent_io_tree *tree, void *private_data);
 244 int try_release_extent_mapping(struct page *page, gfp_t mask);
 245 int try_release_extent_buffer(struct page *page);
 246 int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 247                      struct extent_state **cached);
 248
 249 static inline int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
 250 {
 251         return lock_extent_bits(tree, start, end, NULL);
 252 }
 253
 254 int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end);
 255 int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
 256                           get_extent_t *get_extent, int mirror_num);
 257 int __init extent_io_init(void);
 258 void __cold extent_io_exit(void);
 259
 260 u64 count_range_bits(struct extent_io_tree *tree,
 261                      u64 *start, u64 search_end,
 262                      u64 max_bytes, unsigned bits, int contig);
 263
 264 void free_extent_state(struct extent_state *state);
 265 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
 266                    unsigned bits, int filled,
 267                    struct extent_state *cached_state);
 268 int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 269                 unsigned bits, struct extent_changeset *changeset);
 270 int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 271                      unsigned bits, int wake, int delete,
 272                      struct extent_state **cached);
 273 int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 274                      unsigned bits, int wake, int delete,
 275                      struct extent_state **cached, gfp_t mask,
 276                      struct extent_changeset *changeset);
 277
 278 static inline int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
 279 {
 280         return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL);
 281 }
 282
 283 static inline int unlock_extent_cached(struct extent_io_tree *tree, u64 start,
 284                 u64 end, struct extent_state **cached)
 285 {
 286         return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
 287                                 GFP_NOFS, NULL);
 288 }
 289
 290 static inline int unlock_extent_cached_atomic(struct extent_io_tree *tree,
 291                 u64 start, u64 end, struct extent_state **cached)
 292 {
 293         return __clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
 294                                 GFP_ATOMIC, NULL);
 295 }
 296
 297 static inline int clear_extent_bits(struct extent_io_tree *tree, u64 start,
 298                 u64 end, unsigned bits)
 299 {
 300         int wake = 0;
 301
 302         if (bits & EXTENT_LOCKED)
 303                 wake = 1;
 304
 305         return clear_extent_bit(tree, start, end, bits, wake, 0, NULL);
 306 }
 307
 308 int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
 309                            unsigned bits, struct extent_changeset *changeset);
 310 int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 311                    unsigned bits, u64 *failed_start,
 312                    struct extent_state **cached_state, gfp_t mask);
 313
 314 static inline int set_extent_bits(struct extent_io_tree *tree, u64 start,
 315                 u64 end, unsigned bits)
 316 {
 317         return set_extent_bit(tree, start, end, bits, NULL, NULL, GFP_NOFS);
 318 }
 319
 320 static inline int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
 321                 u64 end, struct extent_state **cached_state)
 322 {
 323         return __clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
 324                                 cached_state, GFP_NOFS, NULL);
 325 }
 326
 327 static inline int set_extent_dirty(struct extent_io_tree *tree, u64 start,
 328                 u64 end, gfp_t mask)
 329 {
 330         return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
 331                               NULL, mask);
 332 }
 333
 334 static inline int clear_extent_dirty(struct extent_io_tree *tree, u64 start,
 335                                      u64 end, struct extent_state **cached)
 336 {
 337         return clear_extent_bit(tree, start, end,
 338                                 EXTENT_DIRTY | EXTENT_DELALLOC |
 339                                 EXTENT_DO_ACCOUNTING, 0, 0, cached);
 340 }
 341
 342 int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
 343                        unsigned bits, unsigned clear_bits,
 344                        struct extent_state **cached_state);
 345
 346 static inline int set_extent_delalloc(struct extent_io_tree *tree, u64 start,
 347                                       u64 end, unsigned int extra_bits,
 348                                       struct extent_state **cached_state)
 349 {
 350         return set_extent_bit(tree, start, end,
 351                               EXTENT_DELALLOC | EXTENT_UPTODATE | extra_bits,
 352                               NULL, cached_state, GFP_NOFS);
 353 }
 354
 355 static inline int set_extent_defrag(struct extent_io_tree *tree, u64 start,
 356                 u64 end, struct extent_state **cached_state)
 357 {
 358         return set_extent_bit(tree, start, end,
 359                               EXTENT_DELALLOC | EXTENT_UPTODATE | EXTENT_DEFRAG,
 360                               NULL, cached_state, GFP_NOFS);
 361 }
 362
 363 static inline int set_extent_new(struct extent_io_tree *tree, u64 start,
 364                 u64 end)
 365 {
 366         return set_extent_bit(tree, start, end, EXTENT_NEW, NULL, NULL,
 367                         GFP_NOFS);
 368 }
 369
 370 static inline int set_extent_uptodate(struct extent_io_tree *tree, u64 start,
 371                 u64 end, struct extent_state **cached_state, gfp_t mask)
 372 {
 373         return set_extent_bit(tree, start, end, EXTENT_UPTODATE, NULL,
 374                               cached_state, mask);
 375 }
 376
 377 int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
 378                           u64 *start_ret, u64 *end_ret, unsigned bits,
 379                           struct extent_state **cached_state);
 380 int extent_invalidatepage(struct extent_io_tree *tree,
 381                           struct page *page, unsigned long offset);
 382 int extent_write_full_page(struct page *page, struct writeback_control *wbc);
 383 int extent_write_locked_range(struct inode *inode, u64 start, u64 end,
 384                               int mode);
 385 int extent_writepages(struct address_space *mapping,
 386                       struct writeback_control *wbc);
 387 int btree_write_cache_pages(struct address_space *mapping,
 388                             struct writeback_control *wbc);
 389 int extent_readpages(struct address_space *mapping, struct list_head *pages,
 390                      unsigned nr_pages);
 391 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 392                 __u64 start, __u64 len);
 393 void set_page_extent_mapped(struct page *page);
 394
 395 struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
 396                                           u64 start);
 397 struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 398                                                   u64 start, unsigned long len);
 399 struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
 400                                                 u64 start);
 401 struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src);
 402 struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info,
 403                                          u64 start);
 404 void free_extent_buffer(struct extent_buffer *eb);
 405 void free_extent_buffer_stale(struct extent_buffer *eb);
 406 #define WAIT_NONE       0
 407 #define WAIT_COMPLETE   1
 408 #define WAIT_PAGE_LOCK  2
 409 int read_extent_buffer_pages(struct extent_io_tree *tree,
 410                              struct extent_buffer *eb, int wait,
 411                              int mirror_num);
 412 void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 413
 414 static inline int num_extent_pages(const struct extent_buffer *eb)
 415 {
 416         return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) -
 417                (eb->start >> PAGE_SHIFT);
 418 }
 419
 420 static inline void extent_buffer_get(struct extent_buffer *eb)
 421 {
 422         atomic_inc(&eb->refs);
 423 }
 424
 425 static inline int extent_buffer_uptodate(struct extent_buffer *eb)
 426 {
 427         return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
 428 }
 429
 430 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
 431                          unsigned long start, unsigned long len);
 432 void read_extent_buffer(const struct extent_buffer *eb, void *dst,
 433                         unsigned long start,
 434                         unsigned long len);
 435 int read_extent_buffer_to_user(const struct extent_buffer *eb,
 436                                void __user *dst, unsigned long start,
 437                                unsigned long len);
 438 void write_extent_buffer_fsid(struct extent_buffer *eb, const void *src);
 439 void write_extent_buffer_chunk_tree_uuid(struct extent_buffer *eb,
 440                 const void *src);
 441 void write_extent_buffer(struct extent_buffer *eb, const void *src,
 442                          unsigned long start, unsigned long len);
 443 void copy_extent_buffer_full(struct extent_buffer *dst,
 444                              struct extent_buffer *src);
 445 void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
 446                         unsigned long dst_offset, unsigned long src_offset,
 447                         unsigned long len);
 448 void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 449                            unsigned long src_offset, unsigned long len);
 450 void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
 451                            unsigned long src_offset, unsigned long len);
 452 void memzero_extent_buffer(struct extent_buffer *eb, unsigned long start,
 453                            unsigned long len);
 454 int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start,
 455                            unsigned long pos);
 456 void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start,
 457                               unsigned long pos, unsigned long len);
 458 void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start,
 459                                 unsigned long pos, unsigned long len);
 460 void clear_extent_buffer_dirty(struct extent_buffer *eb);
 461 bool set_extent_buffer_dirty(struct extent_buffer *eb);
 462 void set_extent_buffer_uptodate(struct extent_buffer *eb);
 463 void clear_extent_buffer_uptodate(struct extent_buffer *eb);
 464 int extent_buffer_under_io(struct extent_buffer *eb);
 465 int map_private_extent_buffer(const struct extent_buffer *eb,
 466                               unsigned long offset, unsigned long min_len,
 467                               char **map, unsigned long *map_start,
 468                               unsigned long *map_len);
 469 void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end);
 470 void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end);
 471 void extent_clear_unlock_delalloc(struct inode *inode, u64 start, u64 end,
 472                                  u64 delalloc_end, struct page *locked_page,
 473                                  unsigned bits_to_clear,
 474                                  unsigned long page_ops);
 475 struct bio *btrfs_bio_alloc(struct block_device *bdev, u64 first_byte);
 476 struct bio *btrfs_io_bio_alloc(unsigned int nr_iovecs);
 477 struct bio *btrfs_bio_clone(struct bio *bio);
 478 struct bio *btrfs_bio_clone_partial(struct bio *orig, int offset, int size);
 479
 480 struct btrfs_fs_info;
 481 struct btrfs_inode;
 482
 483 int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
 484                       u64 length, u64 logical, struct page *page,
 485                       unsigned int pg_offset, int mirror_num);
 486 int clean_io_failure(struct btrfs_fs_info *fs_info,
 487                      struct extent_io_tree *failure_tree,
 488                      struct extent_io_tree *io_tree, u64 start,
 489                      struct page *page, u64 ino, unsigned int pg_offset);
 490 void end_extent_writepage(struct page *page, int err, u64 start, u64 end);
 491 int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
 492                          struct extent_buffer *eb, int mirror_num);
 493
 494 /*
 495  * When IO fails, either with EIO or csum verification fails, we
 496  * try other mirrors that might have a good copy of the data.  This
 497  * io_failure_record is used to record state as we go through all the
 498  * mirrors.  If another mirror has good data, the page is set up to date
 499  * and things continue.  If a good mirror can't be found, the original
 500  * bio end_io callback is called to indicate things have failed.
 501  */
 502 struct io_failure_record {
 503         struct page *page;
 504         u64 start;
 505         u64 len;
 506         u64 logical;
 507         unsigned long bio_flags;
 508         int this_mirror;
 509         int failed_mirror;
 510         int in_validation;
 511 };
 512
 513
 514 void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start,
 515                 u64 end);
 516 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
 517                                 struct io_failure_record **failrec_ret);
 518 bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
 519                             struct io_failure_record *failrec, int fail_mirror);
 520 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio *failed_bio,
 521                                     struct io_failure_record *failrec,
 522                                     struct page *page, int pg_offset, int icsum,
 523                                     bio_end_io_t *endio_func, void *data);
 524 int free_io_failure(struct extent_io_tree *failure_tree,
 525                     struct extent_io_tree *io_tree,
 526                     struct io_failure_record *rec);
 527 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 528 bool find_lock_delalloc_range(struct inode *inode, struct extent_io_tree *tree,
 529                              struct page *locked_page, u64 *start,
 530                              u64 *end);
 531 #endif
 532 struct extent_buffer *alloc_test_extent_buffer(struct btrfs_fs_info *fs_info,
 533                                                u64 start);
 534
 535 #endif