1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2007 Oracle. All rights reserved. 4 */ 5 6 #ifndef BTRFS_INODE_H 7 #define BTRFS_INODE_H 8 9 #include <linux/hash.h> 10 #include <linux/refcount.h> 11 #include <linux/spinlock.h> 12 #include <linux/mutex.h> 13 #include <linux/rwsem.h> 14 #include <linux/fs.h> 15 #include <linux/mm.h> 16 #include <linux/compiler.h> 17 #include <linux/fscrypt.h> 18 #include <linux/lockdep.h> 19 #include <uapi/linux/btrfs_tree.h> 20 #include <trace/events/btrfs.h> 21 #include "block-rsv.h" 22 #include "btrfs_inode.h" 23 #include "extent_map.h" 24 #include "extent_io.h" 25 #include "extent-io-tree.h" 26 #include "ordered-data.h" 27 #include "delayed-inode.h" 28 29 struct extent_state; 30 struct posix_acl; 31 struct iov_iter; 32 struct writeback_control; 33 struct btrfs_root; 34 struct btrfs_fs_info; 35 struct btrfs_trans_handle; 36 37 /* 38 * Since we search a directory based on f_pos (struct dir_context::pos) we have 39 * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so 40 * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()). 41 */ 42 #define BTRFS_DIR_START_INDEX 2 43 44 /* 45 * ordered_data_close is set by truncate when a file that used 46 * to have good data has been truncated to zero. When it is set 47 * the btrfs file release call will add this inode to the 48 * ordered operations list so that we make sure to flush out any 49 * new data the application may have written before commit. 50 */ 51 enum { 52 BTRFS_INODE_FLUSH_ON_CLOSE, 53 BTRFS_INODE_DUMMY, 54 BTRFS_INODE_IN_DEFRAG, 55 BTRFS_INODE_HAS_ASYNC_EXTENT, 56 /* 57 * Always set under the VFS' inode lock, otherwise it can cause races 58 * during fsync (we start as a fast fsync and then end up in a full 59 * fsync racing with ordered extent completion). 60 */ 61 BTRFS_INODE_NEEDS_FULL_SYNC, 62 BTRFS_INODE_COPY_EVERYTHING, 63 BTRFS_INODE_HAS_PROPS, 64 BTRFS_INODE_SNAPSHOT_FLUSH, 65 /* 66 * Set and used when logging an inode and it serves to signal that an 67 * inode does not have xattrs, so subsequent fsyncs can avoid searching 68 * for xattrs to log. This bit must be cleared whenever a xattr is added 69 * to an inode. 70 */ 71 BTRFS_INODE_NO_XATTRS, 72 /* 73 * Set when we are in a context where we need to start a transaction and 74 * have dirty pages with the respective file range locked. This is to 75 * ensure that when reserving space for the transaction, if we are low 76 * on available space and need to flush delalloc, we will not flush 77 * delalloc for this inode, because that could result in a deadlock (on 78 * the file range, inode's io_tree). 79 */ 80 BTRFS_INODE_NO_DELALLOC_FLUSH, 81 /* 82 * Set when we are working on enabling verity for a file. Computing and 83 * writing the whole Merkle tree can take a while so we want to prevent 84 * races where two separate tasks attempt to simultaneously start verity 85 * on the same file. 86 */ 87 BTRFS_INODE_VERITY_IN_PROGRESS, 88 /* Set when this inode is a free space inode. */ 89 BTRFS_INODE_FREE_SPACE_INODE, 90 /* Set when there are no capabilities in XATTs for the inode. */ 91 BTRFS_INODE_NO_CAP_XATTR, 92 }; 93 94 /* in memory btrfs inode */ 95 struct btrfs_inode { 96 /* which subvolume this inode belongs to */ 97 struct btrfs_root *root; 98 99 /* key used to find this inode on disk. This is used by the code 100 * to read in roots of subvolumes 101 */ 102 struct btrfs_key location; 103 104 /* Cached value of inode property 'compression'. */ 105 u8 prop_compress; 106 107 /* 108 * Force compression on the file using the defrag ioctl, could be 109 * different from prop_compress and takes precedence if set. 110 */ 111 u8 defrag_compress; 112 113 /* 114 * Lock for counters and all fields used to determine if the inode is in 115 * the log or not (last_trans, last_sub_trans, last_log_commit, 116 * logged_trans), to access/update delalloc_bytes, new_delalloc_bytes, 117 * defrag_bytes, disk_i_size, outstanding_extents, csum_bytes and to 118 * update the VFS' inode number of bytes used. 119 */ 120 spinlock_t lock; 121 122 /* the extent_tree has caches of all the extent mappings to disk */ 123 struct extent_map_tree extent_tree; 124 125 /* the io_tree does range state (DIRTY, LOCKED etc) */ 126 struct extent_io_tree io_tree; 127 128 /* 129 * Keep track of where the inode has extent items mapped in order to 130 * make sure the i_size adjustments are accurate. Not required when the 131 * filesystem is NO_HOLES, the status can't be set while mounted as 132 * it's a mkfs-time feature. 133 */ 134 struct extent_io_tree *file_extent_tree; 135 136 /* held while logging the inode in tree-log.c */ 137 struct mutex log_mutex; 138 139 /* 140 * Counters to keep track of the number of extent item's we may use due 141 * to delalloc and such. outstanding_extents is the number of extent 142 * items we think we'll end up using, and reserved_extents is the number 143 * of extent items we've reserved metadata for. Protected by 'lock'. 144 */ 145 unsigned outstanding_extents; 146 147 /* used to order data wrt metadata */ 148 spinlock_t ordered_tree_lock; 149 struct rb_root ordered_tree; 150 struct rb_node *ordered_tree_last; 151 152 /* list of all the delalloc inodes in the FS. There are times we need 153 * to write all the delalloc pages to disk, and this list is used 154 * to walk them all. 155 */ 156 struct list_head delalloc_inodes; 157 158 /* node for the red-black tree that links inodes in subvolume root */ 159 struct rb_node rb_node; 160 161 unsigned long runtime_flags; 162 163 /* full 64 bit generation number, struct vfs_inode doesn't have a big 164 * enough field for this. 165 */ 166 u64 generation; 167 168 /* 169 * ID of the transaction handle that last modified this inode. 170 * Protected by 'lock'. 171 */ 172 u64 last_trans; 173 174 /* 175 * ID of the transaction that last logged this inode. 176 * Protected by 'lock'. 177 */ 178 u64 logged_trans; 179 180 /* 181 * Log transaction ID when this inode was last modified. 182 * Protected by 'lock'. 183 */ 184 int last_sub_trans; 185 186 /* A local copy of root's last_log_commit. Protected by 'lock'. */ 187 int last_log_commit; 188 189 union { 190 /* 191 * Total number of bytes pending delalloc, used by stat to 192 * calculate the real block usage of the file. This is used 193 * only for files. Protected by 'lock'. 194 */ 195 u64 delalloc_bytes; 196 /* 197 * The lowest possible index of the next dir index key which 198 * points to an inode that needs to be logged. 199 * This is used only for directories. 200 * Use the helpers btrfs_get_first_dir_index_to_log() and 201 * btrfs_set_first_dir_index_to_log() to access this field. 202 */ 203 u64 first_dir_index_to_log; 204 }; 205 206 union { 207 /* 208 * Total number of bytes pending delalloc that fall within a file 209 * range that is either a hole or beyond EOF (and no prealloc extent 210 * exists in the range). This is always <= delalloc_bytes and this 211 * is used only for files. Protected by 'lock'. 212 */ 213 u64 new_delalloc_bytes; 214 /* 215 * The offset of the last dir index key that was logged. 216 * This is used only for directories. 217 */ 218 u64 last_dir_index_offset; 219 }; 220 221 /* 222 * Total number of bytes pending defrag, used by stat to check whether 223 * it needs COW. Protected by 'lock'. 224 */ 225 u64 defrag_bytes; 226 227 /* 228 * The size of the file stored in the metadata on disk. data=ordered 229 * means the in-memory i_size might be larger than the size on disk 230 * because not all the blocks are written yet. Protected by 'lock'. 231 */ 232 u64 disk_i_size; 233 234 /* 235 * If this is a directory then index_cnt is the counter for the index 236 * number for new files that are created. For an empty directory, this 237 * must be initialized to BTRFS_DIR_START_INDEX. 238 */ 239 u64 index_cnt; 240 241 /* Cache the directory index number to speed the dir/file remove */ 242 u64 dir_index; 243 244 /* the fsync log has some corner cases that mean we have to check 245 * directories to see if any unlinks have been done before 246 * the directory was logged. See tree-log.c for all the 247 * details 248 */ 249 u64 last_unlink_trans; 250 251 /* 252 * The id/generation of the last transaction where this inode was 253 * either the source or the destination of a clone/dedupe operation. 254 * Used when logging an inode to know if there are shared extents that 255 * need special care when logging checksum items, to avoid duplicate 256 * checksum items in a log (which can lead to a corruption where we end 257 * up with missing checksum ranges after log replay). 258 * Protected by the vfs inode lock. 259 */ 260 u64 last_reflink_trans; 261 262 /* 263 * Number of bytes outstanding that are going to need csums. This is 264 * used in ENOSPC accounting. Protected by 'lock'. 265 */ 266 u64 csum_bytes; 267 268 /* Backwards incompatible flags, lower half of inode_item::flags */ 269 u32 flags; 270 /* Read-only compatibility flags, upper half of inode_item::flags */ 271 u32 ro_flags; 272 273 struct btrfs_block_rsv block_rsv; 274 275 struct btrfs_delayed_node *delayed_node; 276 277 /* File creation time. */ 278 u64 i_otime_sec; 279 u32 i_otime_nsec; 280 281 /* Hook into fs_info->delayed_iputs */ 282 struct list_head delayed_iput; 283 284 struct rw_semaphore i_mmap_lock; 285 struct inode vfs_inode; 286 }; 287 288 static inline u64 btrfs_get_first_dir_index_to_log(const struct btrfs_inode *inode) 289 { 290 return READ_ONCE(inode->first_dir_index_to_log); 291 } 292 293 static inline void btrfs_set_first_dir_index_to_log(struct btrfs_inode *inode, 294 u64 index) 295 { 296 WRITE_ONCE(inode->first_dir_index_to_log, index); 297 } 298 299 static inline struct btrfs_inode *BTRFS_I(const struct inode *inode) 300 { 301 return container_of(inode, struct btrfs_inode, vfs_inode); 302 } 303 304 static inline unsigned long btrfs_inode_hash(u64 objectid, 305 const struct btrfs_root *root) 306 { 307 u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME); 308 309 #if BITS_PER_LONG == 32 310 h = (h >> 32) ^ (h & 0xffffffff); 311 #endif 312 313 return (unsigned long)h; 314 } 315 316 #if BITS_PER_LONG == 32 317 318 /* 319 * On 32 bit systems the i_ino of struct inode is 32 bits (unsigned long), so 320 * we use the inode's location objectid which is a u64 to avoid truncation. 321 */ 322 static inline u64 btrfs_ino(const struct btrfs_inode *inode) 323 { 324 u64 ino = inode->location.objectid; 325 326 /* type == BTRFS_ROOT_ITEM_KEY: subvol dir */ 327 if (inode->location.type == BTRFS_ROOT_ITEM_KEY) 328 ino = inode->vfs_inode.i_ino; 329 return ino; 330 } 331 332 #else 333 334 static inline u64 btrfs_ino(const struct btrfs_inode *inode) 335 { 336 return inode->vfs_inode.i_ino; 337 } 338 339 #endif 340 341 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size) 342 { 343 i_size_write(&inode->vfs_inode, size); 344 inode->disk_i_size = size; 345 } 346 347 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode) 348 { 349 return test_bit(BTRFS_INODE_FREE_SPACE_INODE, &inode->runtime_flags); 350 } 351 352 static inline bool is_data_inode(struct inode *inode) 353 { 354 return btrfs_ino(BTRFS_I(inode)) != BTRFS_BTREE_INODE_OBJECTID; 355 } 356 357 static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode, 358 int mod) 359 { 360 lockdep_assert_held(&inode->lock); 361 inode->outstanding_extents += mod; 362 if (btrfs_is_free_space_inode(inode)) 363 return; 364 trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode), 365 mod, inode->outstanding_extents); 366 } 367 368 /* 369 * Called every time after doing a buffered, direct IO or memory mapped write. 370 * 371 * This is to ensure that if we write to a file that was previously fsynced in 372 * the current transaction, then try to fsync it again in the same transaction, 373 * we will know that there were changes in the file and that it needs to be 374 * logged. 375 */ 376 static inline void btrfs_set_inode_last_sub_trans(struct btrfs_inode *inode) 377 { 378 spin_lock(&inode->lock); 379 inode->last_sub_trans = inode->root->log_transid; 380 spin_unlock(&inode->lock); 381 } 382 383 /* 384 * Should be called while holding the inode's VFS lock in exclusive mode, or 385 * while holding the inode's mmap lock (struct btrfs_inode::i_mmap_lock) in 386 * either shared or exclusive mode, or in a context where no one else can access 387 * the inode concurrently (during inode creation or when loading an inode from 388 * disk). 389 */ 390 static inline void btrfs_set_inode_full_sync(struct btrfs_inode *inode) 391 { 392 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); 393 /* 394 * The inode may have been part of a reflink operation in the last 395 * transaction that modified it, and then a fsync has reset the 396 * last_reflink_trans to avoid subsequent fsyncs in the same 397 * transaction to do unnecessary work. So update last_reflink_trans 398 * to the last_trans value (we have to be pessimistic and assume a 399 * reflink happened). 400 * 401 * The ->last_trans is protected by the inode's spinlock and we can 402 * have a concurrent ordered extent completion update it. Also set 403 * last_reflink_trans to ->last_trans only if the former is less than 404 * the later, because we can be called in a context where 405 * last_reflink_trans was set to the current transaction generation 406 * while ->last_trans was not yet updated in the current transaction, 407 * and therefore has a lower value. 408 */ 409 spin_lock(&inode->lock); 410 if (inode->last_reflink_trans < inode->last_trans) 411 inode->last_reflink_trans = inode->last_trans; 412 spin_unlock(&inode->lock); 413 } 414 415 static inline bool btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation) 416 { 417 bool ret = false; 418 419 spin_lock(&inode->lock); 420 if (inode->logged_trans == generation && 421 inode->last_sub_trans <= inode->last_log_commit && 422 inode->last_sub_trans <= btrfs_get_root_last_log_commit(inode->root)) 423 ret = true; 424 spin_unlock(&inode->lock); 425 return ret; 426 } 427 428 /* 429 * Check if the inode has flags compatible with compression 430 */ 431 static inline bool btrfs_inode_can_compress(const struct btrfs_inode *inode) 432 { 433 if (inode->flags & BTRFS_INODE_NODATACOW || 434 inode->flags & BTRFS_INODE_NODATASUM) 435 return false; 436 return true; 437 } 438 439 /* Array of bytes with variable length, hexadecimal format 0x1234 */ 440 #define CSUM_FMT "0x%*phN" 441 #define CSUM_FMT_VALUE(size, bytes) size, bytes 442 443 int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page, 444 u32 pgoff, u8 *csum, const u8 * const csum_expected); 445 bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev, 446 u32 bio_offset, struct bio_vec *bv); 447 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len, 448 u64 *orig_start, u64 *orig_block_len, 449 u64 *ram_bytes, bool nowait, bool strict); 450 451 void btrfs_del_delalloc_inode(struct btrfs_inode *inode); 452 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry); 453 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index); 454 int btrfs_unlink_inode(struct btrfs_trans_handle *trans, 455 struct btrfs_inode *dir, struct btrfs_inode *inode, 456 const struct fscrypt_str *name); 457 int btrfs_add_link(struct btrfs_trans_handle *trans, 458 struct btrfs_inode *parent_inode, struct btrfs_inode *inode, 459 const struct fscrypt_str *name, int add_backref, u64 index); 460 int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry); 461 int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len, 462 int front); 463 464 int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context); 465 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr, 466 bool in_reclaim_context); 467 int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end, 468 unsigned int extra_bits, 469 struct extent_state **cached_state); 470 471 struct btrfs_new_inode_args { 472 /* Input */ 473 struct inode *dir; 474 struct dentry *dentry; 475 struct inode *inode; 476 bool orphan; 477 bool subvol; 478 479 /* Output from btrfs_new_inode_prepare(), input to btrfs_create_new_inode(). */ 480 struct posix_acl *default_acl; 481 struct posix_acl *acl; 482 struct fscrypt_name fname; 483 }; 484 485 int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args, 486 unsigned int *trans_num_items); 487 int btrfs_create_new_inode(struct btrfs_trans_handle *trans, 488 struct btrfs_new_inode_args *args); 489 void btrfs_new_inode_args_destroy(struct btrfs_new_inode_args *args); 490 struct inode *btrfs_new_subvol_inode(struct mnt_idmap *idmap, 491 struct inode *dir); 492 void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state, 493 u32 bits); 494 void btrfs_clear_delalloc_extent(struct btrfs_inode *inode, 495 struct extent_state *state, u32 bits); 496 void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new, 497 struct extent_state *other); 498 void btrfs_split_delalloc_extent(struct btrfs_inode *inode, 499 struct extent_state *orig, u64 split); 500 void btrfs_set_range_writeback(struct btrfs_inode *inode, u64 start, u64 end); 501 void btrfs_evict_inode(struct inode *inode); 502 struct inode *btrfs_alloc_inode(struct super_block *sb); 503 void btrfs_destroy_inode(struct inode *inode); 504 void btrfs_free_inode(struct inode *inode); 505 int btrfs_drop_inode(struct inode *inode); 506 int __init btrfs_init_cachep(void); 507 void __cold btrfs_destroy_cachep(void); 508 struct inode *btrfs_iget_path(struct super_block *s, u64 ino, 509 struct btrfs_root *root, struct btrfs_path *path); 510 struct inode *btrfs_iget(struct super_block *s, u64 ino, struct btrfs_root *root); 511 struct extent_map *btrfs_get_extent(struct btrfs_inode *inode, 512 struct page *page, u64 start, u64 len); 513 int btrfs_update_inode(struct btrfs_trans_handle *trans, 514 struct btrfs_inode *inode); 515 int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, 516 struct btrfs_inode *inode); 517 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode); 518 int btrfs_orphan_cleanup(struct btrfs_root *root); 519 int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size); 520 void btrfs_add_delayed_iput(struct btrfs_inode *inode); 521 void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info); 522 int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info); 523 int btrfs_prealloc_file_range(struct inode *inode, int mode, 524 u64 start, u64 num_bytes, u64 min_size, 525 loff_t actual_len, u64 *alloc_hint); 526 int btrfs_prealloc_file_range_trans(struct inode *inode, 527 struct btrfs_trans_handle *trans, int mode, 528 u64 start, u64 num_bytes, u64 min_size, 529 loff_t actual_len, u64 *alloc_hint); 530 int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page, 531 u64 start, u64 end, struct writeback_control *wbc); 532 int btrfs_writepage_cow_fixup(struct page *page); 533 int btrfs_encoded_io_compression_from_extent(struct btrfs_fs_info *fs_info, 534 int compress_type); 535 int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode, 536 u64 file_offset, u64 disk_bytenr, 537 u64 disk_io_size, 538 struct page **pages); 539 ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter, 540 struct btrfs_ioctl_encoded_io_args *encoded); 541 ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from, 542 const struct btrfs_ioctl_encoded_io_args *encoded); 543 544 ssize_t btrfs_dio_read(struct kiocb *iocb, struct iov_iter *iter, 545 size_t done_before); 546 struct iomap_dio *btrfs_dio_write(struct kiocb *iocb, struct iov_iter *iter, 547 size_t done_before); 548 struct btrfs_inode *btrfs_find_first_inode(struct btrfs_root *root, u64 min_ino); 549 550 extern const struct dentry_operations btrfs_dentry_operations; 551 552 /* Inode locking type flags, by default the exclusive lock is taken. */ 553 enum btrfs_ilock_type { 554 ENUM_BIT(BTRFS_ILOCK_SHARED), 555 ENUM_BIT(BTRFS_ILOCK_TRY), 556 ENUM_BIT(BTRFS_ILOCK_MMAP), 557 }; 558 559 int btrfs_inode_lock(struct btrfs_inode *inode, unsigned int ilock_flags); 560 void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags); 561 void btrfs_update_inode_bytes(struct btrfs_inode *inode, const u64 add_bytes, 562 const u64 del_bytes); 563 void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end); 564 565 #endif 566