fs/btrfs/btrfs_inode.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #ifndef __BTRFS_I__
  20 #define __BTRFS_I__
  21
  22 #include <linux/hash.h>
  23 #include "extent_map.h"
  24 #include "extent_io.h"
  25 #include "ordered-data.h"
  26 #include "delayed-inode.h"
  27
  28 /*
  29  * ordered_data_close is set by truncate when a file that used
  30  * to have good data has been truncated to zero.  When it is set
  31  * the btrfs file release call will add this inode to the
  32  * ordered operations list so that we make sure to flush out any
  33  * new data the application may have written before commit.
  34  */
  35 #define BTRFS_INODE_ORDERED_DATA_CLOSE          0
  36 #define BTRFS_INODE_ORPHAN_META_RESERVED        1
  37 #define BTRFS_INODE_DUMMY                       2
  38 #define BTRFS_INODE_IN_DEFRAG                   3
  39 #define BTRFS_INODE_HAS_ORPHAN_ITEM             4
  40 #define BTRFS_INODE_HAS_ASYNC_EXTENT            5
  41 #define BTRFS_INODE_NEEDS_FULL_SYNC             6
  42 #define BTRFS_INODE_COPY_EVERYTHING             7
  43 #define BTRFS_INODE_IN_DELALLOC_LIST            8
  44 #define BTRFS_INODE_READDIO_NEED_LOCK           9
  45 #define BTRFS_INODE_HAS_PROPS                   10
  46
  47 /* in memory btrfs inode */
  48 struct btrfs_inode {
  49         /* which subvolume this inode belongs to */
  50         struct btrfs_root *root;
  51
  52         /* key used to find this inode on disk.  This is used by the code
  53          * to read in roots of subvolumes
  54          */
  55         struct btrfs_key location;
  56
  57         /*
  58          * Lock for counters and all fields used to determine if the inode is in
  59          * the log or not (last_trans, last_sub_trans, last_log_commit,
  60          * logged_trans).
  61          */
  62         spinlock_t lock;
  63
  64         /* the extent_tree has caches of all the extent mappings to disk */
  65         struct extent_map_tree extent_tree;
  66
  67         /* the io_tree does range state (DIRTY, LOCKED etc) */
  68         struct extent_io_tree io_tree;
  69
  70         /* special utility tree used to record which mirrors have already been
  71          * tried when checksums fail for a given block
  72          */
  73         struct extent_io_tree io_failure_tree;
  74
  75         /* held while logging the inode in tree-log.c */
  76         struct mutex log_mutex;
  77
  78         /* held while doing delalloc reservations */
  79         struct mutex delalloc_mutex;
  80
  81         /* used to order data wrt metadata */
  82         struct btrfs_ordered_inode_tree ordered_tree;
  83
  84         /* list of all the delalloc inodes in the FS.  There are times we need
  85          * to write all the delalloc pages to disk, and this list is used
  86          * to walk them all.
  87          */
  88         struct list_head delalloc_inodes;
  89
  90         /* node for the red-black tree that links inodes in subvolume root */
  91         struct rb_node rb_node;
  92
  93         unsigned long runtime_flags;
  94
  95         /* Keep track of who's O_SYNC/fsyncing currently */
  96         atomic_t sync_writers;
  97
  98         /* full 64 bit generation number, struct vfs_inode doesn't have a big
  99          * enough field for this.
 100          */
 101         u64 generation;
 102
 103         /*
 104          * transid of the trans_handle that last modified this inode
 105          */
 106         u64 last_trans;
 107
 108         /*
 109          * transid that last logged this inode
 110          */
 111         u64 logged_trans;
 112
 113         /*
 114          * log transid when this inode was last modified
 115          */
 116         int last_sub_trans;
 117
 118         /* a local copy of root's last_log_commit */
 119         int last_log_commit;
 120
 121         /* total number of bytes pending delalloc, used by stat to calc the
 122          * real block usage of the file
 123          */
 124         u64 delalloc_bytes;
 125
 126         /*
 127          * Total number of bytes pending delalloc that fall within a file
 128          * range that is either a hole or beyond EOF (and no prealloc extent
 129          * exists in the range). This is always <= delalloc_bytes.
 130          */
 131         u64 new_delalloc_bytes;
 132
 133         /*
 134          * total number of bytes pending defrag, used by stat to check whether
 135          * it needs COW.
 136          */
 137         u64 defrag_bytes;
 138
 139         /*
 140          * the size of the file stored in the metadata on disk.  data=ordered
 141          * means the in-memory i_size might be larger than the size on disk
 142          * because not all the blocks are written yet.
 143          */
 144         u64 disk_i_size;
 145
 146         /*
 147          * if this is a directory then index_cnt is the counter for the index
 148          * number for new files that are created
 149          */
 150         u64 index_cnt;
 151
 152         /* Cache the directory index number to speed the dir/file remove */
 153         u64 dir_index;
 154
 155         /* the fsync log has some corner cases that mean we have to check
 156          * directories to see if any unlinks have been done before
 157          * the directory was logged.  See tree-log.c for all the
 158          * details
 159          */
 160         u64 last_unlink_trans;
 161
 162         /*
 163          * Track the transaction id of the last transaction used to create a
 164          * hard link for the inode. This is used by the log tree (fsync).
 165          */
 166         u64 last_link_trans;
 167
 168         /*
 169          * Number of bytes outstanding that are going to need csums.  This is
 170          * used in ENOSPC accounting.
 171          */
 172         u64 csum_bytes;
 173
 174         /* flags field from the on disk inode */
 175         u32 flags;
 176
 177         /*
 178          * Counters to keep track of the number of extent item's we may use due
 179          * to delalloc and such.  outstanding_extents is the number of extent
 180          * items we think we'll end up using, and reserved_extents is the number
 181          * of extent items we've reserved metadata for.
 182          */
 183         unsigned outstanding_extents;
 184
 185         struct btrfs_block_rsv block_rsv;
 186
 187         /*
 188          * Cached values of inode properties
 189          */
 190         unsigned prop_compress;         /* per-file compression algorithm */
 191         /*
 192          * Force compression on the file using the defrag ioctl, could be
 193          * different from prop_compress and takes precedence if set
 194          */
 195         unsigned defrag_compress;
 196
 197         struct btrfs_delayed_node *delayed_node;
 198
 199         /* File creation time. */
 200         struct timespec i_otime;
 201
 202         /* Hook into fs_info->delayed_iputs */
 203         struct list_head delayed_iput;
 204         long delayed_iput_count;
 205
 206         /*
 207          * To avoid races between lockless (i_mutex not held) direct IO writes
 208          * and concurrent fsync requests. Direct IO writes must acquire read
 209          * access on this semaphore for creating an extent map and its
 210          * corresponding ordered extent. The fast fsync path must acquire write
 211          * access on this semaphore before it collects ordered extents and
 212          * extent maps.
 213          */
 214         struct rw_semaphore dio_sem;
 215
 216         struct inode vfs_inode;
 217 };
 218
 219 extern unsigned char btrfs_filetype_table[];
 220
 221 static inline struct btrfs_inode *BTRFS_I(const struct inode *inode)
 222 {
 223         return container_of(inode, struct btrfs_inode, vfs_inode);
 224 }
 225
 226 static inline unsigned long btrfs_inode_hash(u64 objectid,
 227                                              const struct btrfs_root *root)
 228 {
 229         u64 h = objectid ^ (root->objectid * GOLDEN_RATIO_PRIME);
 230
 231 #if BITS_PER_LONG == 32
 232         h = (h >> 32) ^ (h & 0xffffffff);
 233 #endif
 234
 235         return (unsigned long)h;
 236 }
 237
 238 static inline void btrfs_insert_inode_hash(struct inode *inode)
 239 {
 240         unsigned long h = btrfs_inode_hash(inode->i_ino, BTRFS_I(inode)->root);
 241
 242         __insert_inode_hash(inode, h);
 243 }
 244
 245 static inline u64 btrfs_ino(const struct btrfs_inode *inode)
 246 {
 247         u64 ino = inode->location.objectid;
 248
 249         /*
 250          * !ino: btree_inode
 251          * type == BTRFS_ROOT_ITEM_KEY: subvol dir
 252          */
 253         if (!ino || inode->location.type == BTRFS_ROOT_ITEM_KEY)
 254                 ino = inode->vfs_inode.i_ino;
 255         return ino;
 256 }
 257
 258 static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
 259 {
 260         i_size_write(&inode->vfs_inode, size);
 261         inode->disk_i_size = size;
 262 }
 263
 264 static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
 265 {
 266         struct btrfs_root *root = inode->root;
 267
 268         if (root == root->fs_info->tree_root &&
 269             btrfs_ino(inode) != BTRFS_BTREE_INODE_OBJECTID)
 270                 return true;
 271         if (inode->location.objectid == BTRFS_FREE_INO_OBJECTID)
 272                 return true;
 273         return false;
 274 }
 275
 276 static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
 277                                                  int mod)
 278 {
 279         lockdep_assert_held(&inode->lock);
 280         inode->outstanding_extents += mod;
 281         if (btrfs_is_free_space_inode(inode))
 282                 return;
 283         trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
 284                                                   mod);
 285 }
 286
 287 static inline int btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
 288 {
 289         int ret = 0;
 290
 291         spin_lock(&inode->lock);
 292         if (inode->logged_trans == generation &&
 293             inode->last_sub_trans <= inode->last_log_commit &&
 294             inode->last_sub_trans <= inode->root->last_log_commit) {
 295                 /*
 296                  * After a ranged fsync we might have left some extent maps
 297                  * (that fall outside the fsync's range). So return false
 298                  * here if the list isn't empty, to make sure btrfs_log_inode()
 299                  * will be called and process those extent maps.
 300                  */
 301                 smp_mb();
 302                 if (list_empty(&inode->extent_tree.modified_extents))
 303                         ret = 1;
 304         }
 305         spin_unlock(&inode->lock);
 306         return ret;
 307 }
 308
 309 #define BTRFS_DIO_ORIG_BIO_SUBMITTED    0x1
 310
 311 struct btrfs_dio_private {
 312         struct inode *inode;
 313         unsigned long flags;
 314         u64 logical_offset;
 315         u64 disk_bytenr;
 316         u64 bytes;
 317         void *private;
 318
 319         /* number of bios pending for this dio */
 320         atomic_t pending_bios;
 321
 322         /* IO errors */
 323         int errors;
 324
 325         /* orig_bio is our btrfs_io_bio */
 326         struct bio *orig_bio;
 327
 328         /* dio_bio came from fs/direct-io.c */
 329         struct bio *dio_bio;
 330
 331         /*
 332          * The original bio may be split to several sub-bios, this is
 333          * done during endio of sub-bios
 334          */
 335         blk_status_t (*subio_endio)(struct inode *, struct btrfs_io_bio *,
 336                         blk_status_t);
 337 };
 338
 339 /*
 340  * Disable DIO read nolock optimization, so new dio readers will be forced
 341  * to grab i_mutex. It is used to avoid the endless truncate due to
 342  * nonlocked dio read.
 343  */
 344 static inline void btrfs_inode_block_unlocked_dio(struct btrfs_inode *inode)
 345 {
 346         set_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
 347         smp_mb();
 348 }
 349
 350 static inline void btrfs_inode_resume_unlocked_dio(struct btrfs_inode *inode)
 351 {
 352         smp_mb__before_atomic();
 353         clear_bit(BTRFS_INODE_READDIO_NEED_LOCK, &inode->runtime_flags);
 354 }
 355
 356 static inline void btrfs_print_data_csum_error(struct btrfs_inode *inode,
 357                 u64 logical_start, u32 csum, u32 csum_expected, int mirror_num)
 358 {
 359         struct btrfs_root *root = inode->root;
 360
 361         /* Output minus objectid, which is more meaningful */
 362         if (root->objectid >= BTRFS_LAST_FREE_OBJECTID)
 363                 btrfs_warn_rl(root->fs_info,
 364         "csum failed root %lld ino %lld off %llu csum 0x%08x expected csum 0x%08x mirror %d",
 365                         root->objectid, btrfs_ino(inode),
 366                         logical_start, csum, csum_expected, mirror_num);
 367         else
 368                 btrfs_warn_rl(root->fs_info,
 369         "csum failed root %llu ino %llu off %llu csum 0x%08x expected csum 0x%08x mirror %d",
 370                         root->objectid, btrfs_ino(inode),
 371                         logical_start, csum, csum_expected, mirror_num);
 372 }
 373
 374 bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
 375
 376 #endif