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 "extent_map.h" 12 #include "extent_io.h" 13 #include "ordered-data.h" 14 #include "delayed-inode.h" 15 16 /* 17 * Since we search a directory based on f_pos (struct dir_context::pos) we have 18 * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so 19 * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()). 20 */ 21 #define BTRFS_DIR_START_INDEX 2 22 23 /* 24 * ordered_data_close is set by truncate when a file that used 25 * to have good data has been truncated to zero. When it is set 26 * the btrfs file release call will add this inode to the 27 * ordered operations list so that we make sure to flush out any 28 * new data the application may have written before commit. 29 */ 30 enum { 31 BTRFS_INODE_FLUSH_ON_CLOSE, 32 BTRFS_INODE_DUMMY, 33 BTRFS_INODE_IN_DEFRAG, 34 BTRFS_INODE_HAS_ASYNC_EXTENT, 35 /* 36 * Always set under the VFS' inode lock, otherwise it can cause races 37 * during fsync (we start as a fast fsync and then end up in a full 38 * fsync racing with ordered extent completion). 39 */ 40 BTRFS_INODE_NEEDS_FULL_SYNC, 41 BTRFS_INODE_COPY_EVERYTHING, 42 BTRFS_INODE_IN_DELALLOC_LIST, 43 BTRFS_INODE_HAS_PROPS, 44 BTRFS_INODE_SNAPSHOT_FLUSH, 45 /* 46 * Set and used when logging an inode and it serves to signal that an 47 * inode does not have xattrs, so subsequent fsyncs can avoid searching 48 * for xattrs to log. This bit must be cleared whenever a xattr is added 49 * to an inode. 50 */ 51 BTRFS_INODE_NO_XATTRS, 52 /* 53 * Set when we are in a context where we need to start a transaction and 54 * have dirty pages with the respective file range locked. This is to 55 * ensure that when reserving space for the transaction, if we are low 56 * on available space and need to flush delalloc, we will not flush 57 * delalloc for this inode, because that could result in a deadlock (on 58 * the file range, inode's io_tree). 59 */ 60 BTRFS_INODE_NO_DELALLOC_FLUSH, 61 /* 62 * Set when we are working on enabling verity for a file. Computing and 63 * writing the whole Merkle tree can take a while so we want to prevent 64 * races where two separate tasks attempt to simultaneously start verity 65 * on the same file. 66 */ 67 BTRFS_INODE_VERITY_IN_PROGRESS, 68 /* Set when this inode is a free space inode. */ 69 BTRFS_INODE_FREE_SPACE_INODE, 70 }; 71 72 /* in memory btrfs inode */ 73 struct btrfs_inode { 74 /* which subvolume this inode belongs to */ 75 struct btrfs_root *root; 76 77 /* key used to find this inode on disk. This is used by the code 78 * to read in roots of subvolumes 79 */ 80 struct btrfs_key location; 81 82 /* 83 * Lock for counters and all fields used to determine if the inode is in 84 * the log or not (last_trans, last_sub_trans, last_log_commit, 85 * logged_trans), to access/update new_delalloc_bytes and to update the 86 * VFS' inode number of bytes used. 87 */ 88 spinlock_t lock; 89 90 /* the extent_tree has caches of all the extent mappings to disk */ 91 struct extent_map_tree extent_tree; 92 93 /* the io_tree does range state (DIRTY, LOCKED etc) */ 94 struct extent_io_tree io_tree; 95 96 /* special utility tree used to record which mirrors have already been 97 * tried when checksums fail for a given block 98 */ 99 struct rb_root io_failure_tree; 100 spinlock_t io_failure_lock; 101 102 /* 103 * Keep track of where the inode has extent items mapped in order to 104 * make sure the i_size adjustments are accurate 105 */ 106 struct extent_io_tree file_extent_tree; 107 108 /* held while logging the inode in tree-log.c */ 109 struct mutex log_mutex; 110 111 /* used to order data wrt metadata */ 112 struct btrfs_ordered_inode_tree ordered_tree; 113 114 /* list of all the delalloc inodes in the FS. There are times we need 115 * to write all the delalloc pages to disk, and this list is used 116 * to walk them all. 117 */ 118 struct list_head delalloc_inodes; 119 120 /* node for the red-black tree that links inodes in subvolume root */ 121 struct rb_node rb_node; 122 123 unsigned long runtime_flags; 124 125 /* Keep track of who's O_SYNC/fsyncing currently */ 126 atomic_t sync_writers; 127 128 /* full 64 bit generation number, struct vfs_inode doesn't have a big 129 * enough field for this. 130 */ 131 u64 generation; 132 133 /* 134 * transid of the trans_handle that last modified this inode 135 */ 136 u64 last_trans; 137 138 /* 139 * transid that last logged this inode 140 */ 141 u64 logged_trans; 142 143 /* 144 * log transid when this inode was last modified 145 */ 146 int last_sub_trans; 147 148 /* a local copy of root's last_log_commit */ 149 int last_log_commit; 150 151 /* 152 * Total number of bytes pending delalloc, used by stat to calculate the 153 * real block usage of the file. This is used only for files. 154 */ 155 u64 delalloc_bytes; 156 157 union { 158 /* 159 * Total number of bytes pending delalloc that fall within a file 160 * range that is either a hole or beyond EOF (and no prealloc extent 161 * exists in the range). This is always <= delalloc_bytes and this 162 * is used only for files. 163 */ 164 u64 new_delalloc_bytes; 165 /* 166 * The offset of the last dir index key that was logged. 167 * This is used only for directories. 168 */ 169 u64 last_dir_index_offset; 170 }; 171 172 /* 173 * total number of bytes pending defrag, used by stat to check whether 174 * it needs COW. 175 */ 176 u64 defrag_bytes; 177 178 /* 179 * the size of the file stored in the metadata on disk. data=ordered 180 * means the in-memory i_size might be larger than the size on disk 181 * because not all the blocks are written yet. 182 */ 183 u64 disk_i_size; 184 185 /* 186 * If this is a directory then index_cnt is the counter for the index 187 * number for new files that are created. For an empty directory, this 188 * must be initialized to BTRFS_DIR_START_INDEX. 189 */ 190 u64 index_cnt; 191 192 /* Cache the directory index number to speed the dir/file remove */ 193 u64 dir_index; 194 195 /* the fsync log has some corner cases that mean we have to check 196 * directories to see if any unlinks have been done before 197 * the directory was logged. See tree-log.c for all the 198 * details 199 */ 200 u64 last_unlink_trans; 201 202 /* 203 * The id/generation of the last transaction where this inode was 204 * either the source or the destination of a clone/dedupe operation. 205 * Used when logging an inode to know if there are shared extents that 206 * need special care when logging checksum items, to avoid duplicate 207 * checksum items in a log (which can lead to a corruption where we end 208 * up with missing checksum ranges after log replay). 209 * Protected by the vfs inode lock. 210 */ 211 u64 last_reflink_trans; 212 213 /* 214 * Number of bytes outstanding that are going to need csums. This is 215 * used in ENOSPC accounting. 216 */ 217 u64 csum_bytes; 218 219 /* Backwards incompatible flags, lower half of inode_item::flags */ 220 u32 flags; 221 /* Read-only compatibility flags, upper half of inode_item::flags */ 222 u32 ro_flags; 223 224 /* 225 * Counters to keep track of the number of extent item's we may use due 226 * to delalloc and such. outstanding_extents is the number of extent 227 * items we think we'll end up using, and reserved_extents is the number 228 * of extent items we've reserved metadata for. 229 */ 230 unsigned outstanding_extents; 231 232 struct btrfs_block_rsv block_rsv; 233 234 /* 235 * Cached values of inode properties 236 */ 237 unsigned prop_compress; /* per-file compression algorithm */ 238 /* 239 * Force compression on the file using the defrag ioctl, could be 240 * different from prop_compress and takes precedence if set 241 */ 242 unsigned defrag_compress; 243 244 struct btrfs_delayed_node *delayed_node; 245 246 /* File creation time. */ 247 struct timespec64 i_otime; 248 249 /* Hook into fs_info->delayed_iputs */ 250 struct list_head delayed_iput; 251 252 struct rw_semaphore i_mmap_lock; 253 struct inode vfs_inode; 254 }; 255 256 static inline struct btrfs_inode *BTRFS_I(const struct inode *inode) 257 { 258 return container_of(inode, struct btrfs_inode, vfs_inode); 259 } 260 261 static inline unsigned long btrfs_inode_hash(u64 objectid, 262 const struct btrfs_root *root) 263 { 264 u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME); 265 266 #if BITS_PER_LONG == 32 267 h = (h >> 32) ^ (h & 0xffffffff); 268 #endif 269 270 return (unsigned long)h; 271 } 272 273 #if BITS_PER_LONG == 32 274 275 /* 276 * On 32 bit systems the i_ino of struct inode is 32 bits (unsigned long), so 277 * we use the inode's location objectid which is a u64 to avoid truncation. 278 */ 279 static inline u64 btrfs_ino(const struct btrfs_inode *inode) 280 { 281 u64 ino = inode->location.objectid; 282 283 /* type == BTRFS_ROOT_ITEM_KEY: subvol dir */ 284 if (inode->location.type == BTRFS_ROOT_ITEM_KEY) 285 ino = inode->vfs_inode.i_ino; 286 return ino; 287 } 288 289 #else 290 291 static inline u64 btrfs_ino(const struct btrfs_inode *inode) 292 { 293 return inode->vfs_inode.i_ino; 294 } 295 296 #endif 297 298 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size) 299 { 300 i_size_write(&inode->vfs_inode, size); 301 inode->disk_i_size = size; 302 } 303 304 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode) 305 { 306 return test_bit(BTRFS_INODE_FREE_SPACE_INODE, &inode->runtime_flags); 307 } 308 309 static inline bool is_data_inode(struct inode *inode) 310 { 311 return btrfs_ino(BTRFS_I(inode)) != BTRFS_BTREE_INODE_OBJECTID; 312 } 313 314 static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode, 315 int mod) 316 { 317 lockdep_assert_held(&inode->lock); 318 inode->outstanding_extents += mod; 319 if (btrfs_is_free_space_inode(inode)) 320 return; 321 trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode), 322 mod); 323 } 324 325 /* 326 * Called every time after doing a buffered, direct IO or memory mapped write. 327 * 328 * This is to ensure that if we write to a file that was previously fsynced in 329 * the current transaction, then try to fsync it again in the same transaction, 330 * we will know that there were changes in the file and that it needs to be 331 * logged. 332 */ 333 static inline void btrfs_set_inode_last_sub_trans(struct btrfs_inode *inode) 334 { 335 spin_lock(&inode->lock); 336 inode->last_sub_trans = inode->root->log_transid; 337 spin_unlock(&inode->lock); 338 } 339 340 /* 341 * Should be called while holding the inode's VFS lock in exclusive mode or in a 342 * context where no one else can access the inode concurrently (during inode 343 * creation or when loading an inode from disk). 344 */ 345 static inline void btrfs_set_inode_full_sync(struct btrfs_inode *inode) 346 { 347 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); 348 /* 349 * The inode may have been part of a reflink operation in the last 350 * transaction that modified it, and then a fsync has reset the 351 * last_reflink_trans to avoid subsequent fsyncs in the same 352 * transaction to do unnecessary work. So update last_reflink_trans 353 * to the last_trans value (we have to be pessimistic and assume a 354 * reflink happened). 355 * 356 * The ->last_trans is protected by the inode's spinlock and we can 357 * have a concurrent ordered extent completion update it. Also set 358 * last_reflink_trans to ->last_trans only if the former is less than 359 * the later, because we can be called in a context where 360 * last_reflink_trans was set to the current transaction generation 361 * while ->last_trans was not yet updated in the current transaction, 362 * and therefore has a lower value. 363 */ 364 spin_lock(&inode->lock); 365 if (inode->last_reflink_trans < inode->last_trans) 366 inode->last_reflink_trans = inode->last_trans; 367 spin_unlock(&inode->lock); 368 } 369 370 static inline bool btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation) 371 { 372 bool ret = false; 373 374 spin_lock(&inode->lock); 375 if (inode->logged_trans == generation && 376 inode->last_sub_trans <= inode->last_log_commit && 377 inode->last_sub_trans <= inode->root->last_log_commit) 378 ret = true; 379 spin_unlock(&inode->lock); 380 return ret; 381 } 382 383 /* 384 * Check if the inode has flags compatible with compression 385 */ 386 static inline bool btrfs_inode_can_compress(const struct btrfs_inode *inode) 387 { 388 if (inode->flags & BTRFS_INODE_NODATACOW || 389 inode->flags & BTRFS_INODE_NODATASUM) 390 return false; 391 return true; 392 } 393 394 /* 395 * btrfs_inode_item stores flags in a u64, btrfs_inode stores them in two 396 * separate u32s. These two functions convert between the two representations. 397 */ 398 static inline u64 btrfs_inode_combine_flags(u32 flags, u32 ro_flags) 399 { 400 return (flags | ((u64)ro_flags << 32)); 401 } 402 403 static inline void btrfs_inode_split_flags(u64 inode_item_flags, 404 u32 *flags, u32 *ro_flags) 405 { 406 *flags = (u32)inode_item_flags; 407 *ro_flags = (u32)(inode_item_flags >> 32); 408 } 409 410 /* Array of bytes with variable length, hexadecimal format 0x1234 */ 411 #define CSUM_FMT "0x%*phN" 412 #define CSUM_FMT_VALUE(size, bytes) size, bytes 413 414 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode, 415 u64 logical_start, u8 *csum, u8 *csum_expected, int mirror_num) 416 { 417 struct btrfs_root *root = inode->root; 418 const u32 csum_size = root->fs_info->csum_size; 419 420 /* Output minus objectid, which is more meaningful */ 421 if (root->root_key.objectid >= BTRFS_LAST_FREE_OBJECTID) 422 btrfs_warn_rl(root->fs_info, 423 "csum failed root %lld ino %lld off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", 424 root->root_key.objectid, btrfs_ino(inode), 425 logical_start, 426 CSUM_FMT_VALUE(csum_size, csum), 427 CSUM_FMT_VALUE(csum_size, csum_expected), 428 mirror_num); 429 else 430 btrfs_warn_rl(root->fs_info, 431 "csum failed root %llu ino %llu off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d", 432 root->root_key.objectid, btrfs_ino(inode), 433 logical_start, 434 CSUM_FMT_VALUE(csum_size, csum), 435 CSUM_FMT_VALUE(csum_size, csum_expected), 436 mirror_num); 437 } 438 439 #endif 440