fs/btrfs/btrfs_inode.h

   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  * ordered_data_close is set by truncate when a file that used
  18  * to have good data has been truncated to zero.  When it is set
  19  * the btrfs file release call will add this inode to the
  20  * ordered operations list so that we make sure to flush out any
  21  * new data the application may have written before commit.
  22  */
  23 enum {
  24         BTRFS_INODE_ORDERED_DATA_CLOSE,
  25         BTRFS_INODE_DUMMY,
  26         BTRFS_INODE_IN_DEFRAG,
  27         BTRFS_INODE_HAS_ASYNC_EXTENT,
  28         BTRFS_INODE_NEEDS_FULL_SYNC,
  29         BTRFS_INODE_COPY_EVERYTHING,
  30         BTRFS_INODE_IN_DELALLOC_LIST,
  31         BTRFS_INODE_READDIO_NEED_LOCK,
  32         BTRFS_INODE_HAS_PROPS,
  33         BTRFS_INODE_SNAPSHOT_FLUSH,
  34 };
  35
  36 /* in memory btrfs inode */
  37 struct btrfs_inode {
  38         /* which subvolume this inode belongs to */
  39         struct btrfs_root *root;
  40
  41         /* key used to find this inode on disk.  This is used by the code
  42          * to read in roots of subvolumes
  43          */
  44         struct btrfs_key location;
  45
  46         /*
  47          * Lock for counters and all fields used to determine if the inode is in
  48          * the log or not (last_trans, last_sub_trans, last_log_commit,
  49          * logged_trans).
  50          */
  51         spinlock_t lock;
  52
  53         /* the extent_tree has caches of all the extent mappings to disk */
  54         struct extent_map_tree extent_tree;
  55
  56         /* the io_tree does range state (DIRTY, LOCKED etc) */
  57         struct extent_io_tree io_tree;
  58
  59         /* special utility tree used to record which mirrors have already been
  60          * tried when checksums fail for a given block
  61          */
  62         struct extent_io_tree io_failure_tree;
  63
  64         /*
  65          * Keep track of where the inode has extent items mapped in order to
  66          * make sure the i_size adjustments are accurate
  67          */
  68         struct extent_io_tree file_extent_tree;
  69
  70         /* held while logging the inode in tree-log.c */
  71         struct mutex log_mutex;
  72
  73         /* used to order data wrt metadata */
  74         struct btrfs_ordered_inode_tree ordered_tree;
  75
  76         /* list of all the delalloc inodes in the FS.  There are times we need
  77          * to write all the delalloc pages to disk, and this list is used
  78          * to walk them all.
  79          */
  80         struct list_head delalloc_inodes;
  81
  82         /* node for the red-black tree that links inodes in subvolume root */
  83         struct rb_node rb_node;
  84
  85         unsigned long runtime_flags;
  86
  87         /* Keep track of who's O_SYNC/fsyncing currently */
  88         atomic_t sync_writers;
  89
  90         /* full 64 bit generation number, struct vfs_inode doesn't have a big
  91          * enough field for this.
  92          */
  93         u64 generation;
  94
  95         /*
  96          * transid of the trans_handle that last modified this inode
  97          */
  98         u64 last_trans;
  99
 100         /*
 101          * transid that last logged this inode
 102          */
 103         u64 logged_trans;
 104
 105         /*
 106          * log transid when this inode was last modified
 107          */
 108         int last_sub_trans;
 109
 110         /* a local copy of root's last_log_commit */
 111         int last_log_commit;
 112
 113         /* total number of bytes pending delalloc, used by stat to calc the
 114          * real block usage of the file
 115          */
 116         u64 delalloc_bytes;
 117
 118         /*
 119          * Total number of bytes pending delalloc that fall within a file
 120          * range that is either a hole or beyond EOF (and no prealloc extent
 121          * exists in the range). This is always <= delalloc_bytes.
 122          */
 123         u64 new_delalloc_bytes;
 124
 125         /*
 126          * total number of bytes pending defrag, used by stat to check whether
 127          * it needs COW.
 128          */
 129         u64 defrag_bytes;
 130
 131         /*
 132          * the size of the file stored in the metadata on disk.  data=ordered
 133          * means the in-memory i_size might be larger than the size on disk
 134          * because not all the blocks are written yet.
 135          */
 136         u64 disk_i_size;
 137
 138         /*
 139          * if this is a directory then index_cnt is the counter for the index
 140          * number for new files that are created
 141          */
 142         u64 index_cnt;
 143
 144         /* Cache the directory index number to speed the dir/file remove */
 145         u64 dir_index;
 146
 147         /* the fsync log has some corner cases that mean we have to check
 148          * directories to see if any unlinks have been done before
 149          * the directory was logged.  See tree-log.c for all the
 150          * details
 151          */
 152         u64 last_unlink_trans;
 153
 154         /*
 155          * The id/generation of the last transaction where this inode was
 156          * either the source or the destination of a clone/dedupe operation.
 157          * Used when logging an inode to know if there are shared extents that
 158          * need special care when logging checksum items, to avoid duplicate
 159          * checksum items in a log (which can lead to a corruption where we end
 160          * up with missing checksum ranges after log replay).
 161          * Protected by the vfs inode lock.
 162          */
 163         u64 last_reflink_trans;
 164
 165         /*
 166          * Number of bytes outstanding that are going to need csums.  This is
 167          * used in ENOSPC accounting.
 168          */
 169         u64 csum_bytes;
 170
 171         /* flags field from the on disk inode */
 172         u32 flags;
 173
 174         /*
 175          * Counters to keep track of the number of extent item's we may use due
 176          * to delalloc and such.  outstanding_extents is the number of extent
 177          * items we think we'll end up using, and reserved_extents is the number
 178          * of extent items we've reserved metadata for.
 179          */
 180         unsigned outstanding_extents;
 181
 182         struct btrfs_block_rsv block_rsv;
 183
 184         /*
 185          * Cached values of inode properties
 186          */
 187         unsigned prop_compress;         /* per-file compression algorithm */
 188         /*
 189          * Force compression on the file using the defrag ioctl, could be
 190          * different from prop_compress and takes precedence if set
 191          */
 192         unsigned defrag_compress;
 193
 194         struct btrfs_delayed_node *delayed_node;
 195
 196         /* File creation time. */
 197         struct timespec64 i_otime;
 198
 199         /* Hook into fs_info->delayed_iputs */
 200         struct list_head delayed_iput;
 201
 202         /*
 203          * To avoid races between lockless (i_mutex not held) direct IO writes
 204          * and concurrent fsync requests. Direct IO writes must acquire read
 205          * access on this semaphore for creating an extent map and its
 206          * corresponding ordered extent. The fast fsync path must acquire write
 207          * access on this semaphore before it collects ordered extents and
 208          * extent maps.
 209          */
 210         struct rw_semaphore dio_sem;
 211
 212         struct inode vfs_inode;
 213 };
 214
 215 static inline struct btrfs_inode *BTRFS_I(const struct inode *inode)
 216 {
 217         return container_of(inode, struct btrfs_inode, vfs_inode);
 218 }
 219
 220 static inline unsigned long btrfs_inode_hash(u64 objectid,
 221                                              const struct btrfs_root *root)
 222 {
 223         u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME);
 224
 225 #if BITS_PER_LONG == 32
 226         h = (h >> 32) ^ (h & 0xffffffff);
 227 #endif
 228
 229         return (unsigned long)h;
 230 }
 231
 232 static inline void btrfs_insert_inode_hash(struct inode *inode)
 233 {
 234         unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
 235
 236         __insert_inode_hash(inode, h);
 237 }
 238
 239 static inline u64 btrfs_ino(const struct btrfs_inode *inode)
 240 {
 241         u64 ino = inode->location.objectid;
 242
 243         /*
 244          * !ino: btree_inode
 245          * type == BTRFS_ROOT_ITEM_KEY: subvol dir
 246          */
 247         if (!ino || inode->location.type == BTRFS_ROOT_ITEM_KEY)
 248                 ino = inode->vfs_inode.i_ino;
 249         return ino;
 250 }
 251
 252 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
 253 {
 254         i_size_write(&inode->vfs_inode, size);
 255         inode->disk_i_size = size;
 256 }
 257
 258 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
 259 {
 260         struct btrfs_root *root = inode->root;
 261
 262         if (root == root->fs_info->tree_root &&
 263             btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
 264                 return true;
 265         if (inode->location.objectid == BTRFS_FREE_INO_OBJECTID)
 266                 return true;
 267         return false;
 268 }
 269
 270 static inline bool is_data_inode(struct inode *inode)
 271 {
 272         return btrfs_ino(BTRFS_I(inode)) != BTRFS_BTREE_INODE_OBJECTID;
 273 }
 274
 275 static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
 276                                                  int mod)
 277 {
 278         lockdep_assert_held(&inode->lock);
 279         inode->outstanding_extents += mod;
 280         if (btrfs_is_free_space_inode(inode))
 281                 return;
 282         trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
 283                                                   mod);
 284 }
 285
 286 static inline int btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
 287 {
 288         int ret = 0;
 289
 290         spin_lock(&inode->lock);
 291         if (inode->logged_trans == generation &&
 292             inode->last_sub_trans <= inode->last_log_commit &&
 293             inode->last_sub_trans <= inode->root->last_log_commit) {
 294                 /*
 295                  * After a ranged fsync we might have left some extent maps
 296                  * (that fall outside the fsync's range). So return false
 297                  * here if the list isn't empty, to make sure btrfs_log_inode()
 298                  * will be called and process those extent maps.
 299                  */
 300                 smp_mb();
 301                 if (list_empty(&inode->extent_tree.modified_extents))
 302                         ret = 1;
 303         }
 304         spin_unlock(&inode->lock);
 305         return ret;
 306 }
 307
 308 struct btrfs_dio_private {
 309         struct inode *inode;
 310         u64 logical_offset;
 311         u64 disk_bytenr;
 312         u64 bytes;
 313
 314         /*
 315          * References to this structure. There is one reference per in-flight
 316          * bio plus one while we're still setting up.
 317          */
 318         refcount_t refs;
 319
 320         /* dio_bio came from fs/direct-io.c */
 321         struct bio *dio_bio;
 322
 323         /* Array of checksums */
 324         u8 csums[];
 325 };
 326
 327 /*
 328  * Disable DIO read nolock optimization, so new dio readers will be forced
 329  * to grab i_mutex. It is used to avoid the endless truncate due to
 330  * nonlocked dio read.
 331  */
 332 static inline void btrfs_inode_block_unlocked_dio(struct btrfs_inode *inode)
 333 {
 334         set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
 335         smp_mb();
 336 }
 337
 338 static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode)
 339 {
 340         smp_mb__before_atomic();
 341         clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
 342 }
 343
 344 /* Array of bytes with variable length, hexadecimal format 0x1234 */
 345 #define CSUM_FMT                                "0x%*phN"
 346 #define CSUM_FMT_VALUE(size, bytes)             size, bytes
 347
 348 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode,
 349                 u64 logical_start, u8 *csum, u8 *csum_expected, int mirror_num)
 350 {
 351         struct btrfs_root *root = inode->root;
 352         struct btrfs_super_block *sb = root->fs_info->super_copy;
 353         const u16 csum_size = btrfs_super_csum_size(sb);
 354
 355         /* Output minus objectid, which is more meaningful */
 356         if (root->root_key.objectid >= BTRFS_LAST_FREE_OBJECTID)
 357                 btrfs_warn_rl(root->fs_info,
 358 "csum failed root %lld ino %lld off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d",
 359                         root->root_key.objectid, btrfs_ino(inode),
 360                         logical_start,
 361                         CSUM_FMT_VALUE(csum_size, csum),
 362                         CSUM_FMT_VALUE(csum_size, csum_expected),
 363                         mirror_num);
 364         else
 365                 btrfs_warn_rl(root->fs_info,
 366 "csum failed root %llu ino %llu off %llu csum " CSUM_FMT " expected csum " CSUM_FMT " mirror %d",
 367                         root->root_key.objectid, btrfs_ino(inode),
 368                         logical_start,
 369                         CSUM_FMT_VALUE(csum_size, csum),
 370                         CSUM_FMT_VALUE(csum_size, csum_expected),
 371                         mirror_num);
 372 }
 373
 374 #endif