fs/btrfs/ctree.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__
  20 #define __BTRFS__
  21
  22 #include <linux/fs.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/completion.h>
  25 #include "bit-radix.h"
  26 #include "extent_map.h"
  27
  28 struct btrfs_trans_handle;
  29 struct btrfs_transaction;
  30 extern struct kmem_cache *btrfs_trans_handle_cachep;
  31 extern struct kmem_cache *btrfs_transaction_cachep;
  32 extern struct kmem_cache *btrfs_bit_radix_cachep;
  33 extern struct kmem_cache *btrfs_path_cachep;
  34
  35 #define BTRFS_MAGIC "_B2RfS_M"
  36
  37 #define BTRFS_ROOT_TREE_OBJECTID 1ULL
  38 #define BTRFS_EXTENT_TREE_OBJECTID 2ULL
  39 #define BTRFS_FS_TREE_OBJECTID 3ULL
  40 #define BTRFS_ROOT_TREE_DIR_OBJECTID 4ULL
  41 #define BTRFS_FIRST_FREE_OBJECTID 5ULL
  42
  43 /*
  44  * we can actually store much bigger names, but lets not confuse the rest
  45  * of linux
  46  */
  47 #define BTRFS_NAME_LEN 255
  48
  49 /* 32 bytes in various csum fields */
  50 #define BTRFS_CSUM_SIZE 32
  51 /* four bytes for CRC32 */
  52 #define BTRFS_CRC32_SIZE 4
  53 #define BTRFS_EMPTY_DIR_SIZE 6
  54
  55 #define BTRFS_FT_UNKNOWN        0
  56 #define BTRFS_FT_REG_FILE       1
  57 #define BTRFS_FT_DIR            2
  58 #define BTRFS_FT_CHRDEV         3
  59 #define BTRFS_FT_BLKDEV         4
  60 #define BTRFS_FT_FIFO           5
  61 #define BTRFS_FT_SOCK           6
  62 #define BTRFS_FT_SYMLINK        7
  63 #define BTRFS_FT_MAX            8
  64
  65 /*
  66  * the key defines the order in the tree, and so it also defines (optimal)
  67  * block layout.  objectid corresonds to the inode number.  The flags
  68  * tells us things about the object, and is a kind of stream selector.
  69  * so for a given inode, keys with flags of 1 might refer to the inode
  70  * data, flags of 2 may point to file data in the btree and flags == 3
  71  * may point to extents.
  72  *
  73  * offset is the starting byte offset for this key in the stream.
  74  *
  75  * btrfs_disk_key is in disk byte order.  struct btrfs_key is always
  76  * in cpu native order.  Otherwise they are identical and their sizes
  77  * should be the same (ie both packed)
  78  */
  79 struct btrfs_disk_key {
  80         __le64 objectid;
  81         u8 type;
  82         __le64 offset;
  83 } __attribute__ ((__packed__));
  84
  85 struct btrfs_key {
  86         u64 objectid;
  87         u8 type;
  88         u64 offset;
  89 } __attribute__ ((__packed__));
  90
  91 #define BTRFS_FSID_SIZE 16
  92 /*
  93  * every tree block (leaf or node) starts with this header.
  94  */
  95 struct btrfs_header {
  96         u8 csum[BTRFS_CSUM_SIZE];
  97         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
  98         __le64 blocknr; /* which block this node is supposed to live in */
  99         __le64 generation;
 100         __le64 owner;
 101         __le32 nritems;
 102         __le16 flags;
 103         u8 level;
 104 } __attribute__ ((__packed__));
 105
 106 #define BTRFS_MAX_LEVEL 8
 107 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
 108                                 sizeof(struct btrfs_header)) / \
 109                                (sizeof(struct btrfs_disk_key) + sizeof(u64)))
 110 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
 111 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
 112 #define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
 113                                         sizeof(struct btrfs_item) - \
 114                                         sizeof(struct btrfs_file_extent_item))
 115
 116 /*
 117  * the super block basically lists the main trees of the FS
 118  * it currently lacks any block count etc etc
 119  */
 120 struct btrfs_super_block {
 121         u8 csum[BTRFS_CSUM_SIZE];
 122         /* the first 3 fields must match struct btrfs_header */
 123         u8 fsid[16];    /* FS specific uuid */
 124         __le64 blocknr; /* this block number */
 125         __le64 magic;
 126         __le64 generation;
 127         __le64 root;
 128         __le64 total_blocks;
 129         __le64 blocks_used;
 130         __le64 root_dir_objectid;
 131         __le32 sectorsize;
 132         __le32 nodesize;
 133         __le32 leafsize;
 134 } __attribute__ ((__packed__));
 135
 136 /*
 137  * A leaf is full of items. offset and size tell us where to find
 138  * the item in the leaf (relative to the start of the data area)
 139  */
 140 struct btrfs_item {
 141         struct btrfs_disk_key key;
 142         __le32 offset;
 143         __le32 size;
 144 } __attribute__ ((__packed__));
 145
 146 /*
 147  * leaves have an item area and a data area:
 148  * [item0, item1....itemN] [free space] [dataN...data1, data0]
 149  *
 150  * The data is separate from the items to get the keys closer together
 151  * during searches.
 152  */
 153 struct btrfs_leaf {
 154         struct btrfs_header header;
 155         struct btrfs_item items[];
 156 } __attribute__ ((__packed__));
 157
 158 /*
 159  * all non-leaf blocks are nodes, they hold only keys and pointers to
 160  * other blocks
 161  */
 162 struct btrfs_key_ptr {
 163         struct btrfs_disk_key key;
 164         __le64 blockptr;
 165 } __attribute__ ((__packed__));
 166
 167 struct btrfs_node {
 168         struct btrfs_header header;
 169         struct btrfs_key_ptr ptrs[];
 170 } __attribute__ ((__packed__));
 171
 172 /*
 173  * btrfs_paths remember the path taken from the root down to the leaf.
 174  * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
 175  * to any other levels that are present.
 176  *
 177  * The slots array records the index of the item or block pointer
 178  * used while walking the tree.
 179  */
 180 struct btrfs_path {
 181         struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
 182         int slots[BTRFS_MAX_LEVEL];
 183         int reada;
 184         int lowest_level;
 185 };
 186
 187 /*
 188  * items in the extent btree are used to record the objectid of the
 189  * owner of the block and the number of references
 190  */
 191 struct btrfs_extent_item {
 192         __le32 refs;
 193         __le64 owner;
 194 } __attribute__ ((__packed__));
 195
 196 struct btrfs_inode_timespec {
 197         __le64 sec;
 198         __le32 nsec;
 199 } __attribute__ ((__packed__));
 200
 201 /*
 202  * there is no padding here on purpose.  If you want to extent the inode,
 203  * make a new item type
 204  */
 205 struct btrfs_inode_item {
 206         __le64 generation;
 207         __le64 size;
 208         __le64 nblocks;
 209         __le64 block_group;
 210         __le32 nlink;
 211         __le32 uid;
 212         __le32 gid;
 213         __le32 mode;
 214         __le32 rdev;
 215         __le16 flags;
 216         __le16 compat_flags;
 217         struct btrfs_inode_timespec atime;
 218         struct btrfs_inode_timespec ctime;
 219         struct btrfs_inode_timespec mtime;
 220         struct btrfs_inode_timespec otime;
 221 } __attribute__ ((__packed__));
 222
 223 struct btrfs_dir_item {
 224         struct btrfs_disk_key location;
 225         __le16 flags;
 226         __le16 name_len;
 227         u8 type;
 228 } __attribute__ ((__packed__));
 229
 230 struct btrfs_root_item {
 231         struct btrfs_inode_item inode;
 232         __le64 root_dirid;
 233         __le64 blocknr;
 234         __le64 block_limit;
 235         __le64 blocks_used;
 236         __le32 flags;
 237         __le32 refs;
 238         struct btrfs_disk_key drop_progress;
 239         u8 drop_level;
 240 } __attribute__ ((__packed__));
 241
 242 #define BTRFS_FILE_EXTENT_REG 0
 243 #define BTRFS_FILE_EXTENT_INLINE 1
 244
 245 struct btrfs_file_extent_item {
 246         __le64 generation;
 247         u8 type;
 248         /*
 249          * disk space consumed by the extent, checksum blocks are included
 250          * in these numbers
 251          */
 252         __le64 disk_blocknr;
 253         __le64 disk_num_blocks;
 254         /*
 255          * the logical offset in file blocks (no csums)
 256          * this extent record is for.  This allows a file extent to point
 257          * into the middle of an existing extent on disk, sharing it
 258          * between two snapshots (useful if some bytes in the middle of the
 259          * extent have changed
 260          */
 261         __le64 offset;
 262         /*
 263          * the logical number of file blocks (no csums included)
 264          */
 265         __le64 num_blocks;
 266 } __attribute__ ((__packed__));
 267
 268 struct btrfs_csum_item {
 269         u8 csum;
 270 } __attribute__ ((__packed__));
 271
 272 /* tag for the radix tree of block groups in ram */
 273 #define BTRFS_BLOCK_GROUP_DIRTY 0
 274 #define BTRFS_BLOCK_GROUP_AVAIL 1
 275 #define BTRFS_BLOCK_GROUP_SIZE (256 * 1024 * 1024)
 276
 277
 278 #define BTRFS_BLOCK_GROUP_DATA 1
 279 struct btrfs_block_group_item {
 280         __le64 used;
 281         u8 flags;
 282 } __attribute__ ((__packed__));
 283
 284 struct btrfs_block_group_cache {
 285         struct btrfs_key key;
 286         struct btrfs_block_group_item item;
 287         struct radix_tree_root *radix;
 288         u64 first_free;
 289         u64 last_alloc;
 290         u64 pinned;
 291         u64 last_prealloc;
 292         int data;
 293         int cached;
 294 };
 295
 296 struct btrfs_fs_info {
 297         u8 fsid[BTRFS_FSID_SIZE];
 298         struct btrfs_root *extent_root;
 299         struct btrfs_root *tree_root;
 300         struct radix_tree_root fs_roots_radix;
 301         struct radix_tree_root pending_del_radix;
 302         struct radix_tree_root pinned_radix;
 303         struct radix_tree_root block_group_radix;
 304         struct radix_tree_root block_group_data_radix;
 305         struct radix_tree_root extent_map_radix;
 306         struct radix_tree_root extent_ins_radix;
 307         u64 generation;
 308         u64 last_trans_committed;
 309         struct btrfs_transaction *running_transaction;
 310         struct btrfs_super_block super_copy;
 311         struct extent_buffer *sb_buffer;
 312         struct super_block *sb;
 313         struct inode *btree_inode;
 314         struct mutex trans_mutex;
 315         struct mutex fs_mutex;
 316         struct list_head trans_list;
 317         struct list_head dead_roots;
 318         struct delayed_work trans_work;
 319         struct kobject super_kobj;
 320         struct completion kobj_unregister;
 321         int do_barriers;
 322         int closing;
 323 };
 324
 325 /*
 326  * in ram representation of the tree.  extent_root is used for all allocations
 327  * and for the extent tree extent_root root.
 328  */
 329 struct btrfs_root {
 330         struct extent_buffer *node;
 331         struct extent_buffer *commit_root;
 332         struct btrfs_root_item root_item;
 333         struct btrfs_key root_key;
 334         struct btrfs_fs_info *fs_info;
 335         struct inode *inode;
 336         struct kobject root_kobj;
 337         struct completion kobj_unregister;
 338         struct rw_semaphore snap_sem;
 339         u64 objectid;
 340         u64 last_trans;
 341
 342         /* data allocations are done in sectorsize units */
 343         u32 sectorsize;
 344
 345         /* node allocations are done in nodesize units */
 346         u32 nodesize;
 347
 348         /* leaf allocations are done in leafsize units */
 349         u32 leafsize;
 350
 351         u32 type;
 352         u64 highest_inode;
 353         u64 last_inode_alloc;
 354         int ref_cows;
 355         struct btrfs_key defrag_progress;
 356         int defrag_running;
 357         int defrag_level;
 358         char *name;
 359 };
 360
 361 /*
 362  * inode items have the data typically returned from stat and store other
 363  * info about object characteristics.  There is one for every file and dir in
 364  * the FS
 365  */
 366 #define BTRFS_INODE_ITEM_KEY            1
 367
 368 /* reserve 2-15 close to the inode for later flexibility */
 369
 370 /*
 371  * dir items are the name -> inode pointers in a directory.  There is one
 372  * for every name in a directory.
 373  */
 374 #define BTRFS_DIR_ITEM_KEY      16
 375 #define BTRFS_DIR_INDEX_KEY     17
 376 /*
 377  * extent data is for file data
 378  */
 379 #define BTRFS_EXTENT_DATA_KEY   18
 380 /*
 381  * csum items have the checksums for data in the extents
 382  */
 383 #define BTRFS_CSUM_ITEM_KEY     19
 384
 385 /* reserve 20-31 for other file stuff */
 386
 387 /*
 388  * root items point to tree roots.  There are typically in the root
 389  * tree used by the super block to find all the other trees
 390  */
 391 #define BTRFS_ROOT_ITEM_KEY     32
 392 /*
 393  * extent items are in the extent map tree.  These record which blocks
 394  * are used, and how many references there are to each block
 395  */
 396 #define BTRFS_EXTENT_ITEM_KEY   33
 397
 398 /*
 399  * block groups give us hints into the extent allocation trees.  Which
 400  * blocks are free etc etc
 401  */
 402 #define BTRFS_BLOCK_GROUP_ITEM_KEY 34
 403
 404 /*
 405  * string items are for debugging.  They just store a short string of
 406  * data in the FS
 407  */
 408 #define BTRFS_STRING_ITEM_KEY   253
 409
 410 /* some macros to generate set/get funcs for the struct fields.  This
 411  * assumes there is a lefoo_to_cpu for every type, so lets make a simple
 412  * one for u8:
 413  */
 414 #define le8_to_cpu(v) (v)
 415 #define cpu_to_le8(v) (v)
 416 #define __le8 u8
 417
 418 #define read_eb_member(eb, ptr, type, member, result) (                 \
 419         read_extent_buffer(eb, (char *)(result),                        \
 420                            ((unsigned long)(ptr)) +                     \
 421                             offsetof(type, member),                     \
 422                            sizeof(((type *)0)->member)))
 423
 424 #define write_eb_member(eb, ptr, type, member, result) (                \
 425         write_extent_buffer(eb, (char *)(result),                       \
 426                            ((unsigned long)(ptr)) +                     \
 427                             offsetof(type, member),                     \
 428                            sizeof(((type *)0)->member)))
 429
 430 #define BTRFS_SETGET_FUNCS(name, type, member, bits)                    \
 431 static inline u##bits btrfs_##name(struct extent_buffer *eb,            \
 432                                    type *s)                             \
 433 {                                                                       \
 434         __le##bits res;                                                 \
 435         read_eb_member(eb, s, type, member, &res);                      \
 436         return le##bits##_to_cpu(res);                                  \
 437 }                                                                       \
 438 static inline void btrfs_set_##name(struct extent_buffer *eb,           \
 439                                     type *s, u##bits val)               \
 440 {                                                                       \
 441         val = cpu_to_le##bits(val);                                     \
 442         write_eb_member(eb, s, type, member, &val);                     \
 443 }
 444
 445 #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits)             \
 446 static inline u##bits btrfs_##name(struct extent_buffer *eb)            \
 447 {                                                                       \
 448         __le##bits res;                                                 \
 449         read_eb_member(eb, NULL, type, member, &res);                   \
 450         return le##bits##_to_cpu(res);                                  \
 451 }                                                                       \
 452 static inline void btrfs_set_##name(struct extent_buffer *eb,           \
 453                                     u##bits val)                        \
 454 {                                                                       \
 455         val = cpu_to_le##bits(val);                                     \
 456         write_eb_member(eb, NULL, type, member, &val);                  \
 457 }
 458
 459 #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits)              \
 460 static inline u##bits btrfs_##name(type *s)                             \
 461 {                                                                       \
 462         return le##bits##_to_cpu(s->member);                            \
 463 }                                                                       \
 464 static inline void btrfs_set_##name(type *s, u##bits val)               \
 465 {                                                                       \
 466         s->member = cpu_to_le##bits(val);                               \
 467 }
 468
 469 /* struct btrfs_block_group_item */
 470 BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item,
 471                          used, 64);
 472 BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item,
 473                          used, 64);
 474
 475 /* struct btrfs_inode_item */
 476 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
 477 BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64);
 478 BTRFS_SETGET_FUNCS(inode_nblocks, struct btrfs_inode_item, nblocks, 64);
 479 BTRFS_SETGET_FUNCS(inode_block_group, struct btrfs_inode_item, block_group, 64);
 480 BTRFS_SETGET_FUNCS(inode_nlink, struct btrfs_inode_item, nlink, 32);
 481 BTRFS_SETGET_FUNCS(inode_uid, struct btrfs_inode_item, uid, 32);
 482 BTRFS_SETGET_FUNCS(inode_gid, struct btrfs_inode_item, gid, 32);
 483 BTRFS_SETGET_FUNCS(inode_mode, struct btrfs_inode_item, mode, 32);
 484 BTRFS_SETGET_FUNCS(inode_rdev, struct btrfs_inode_item, rdev, 32);
 485 BTRFS_SETGET_FUNCS(inode_flags, struct btrfs_inode_item, flags, 16);
 486 BTRFS_SETGET_FUNCS(inode_compat_flags, struct btrfs_inode_item,
 487                    compat_flags, 16);
 488
 489 static inline struct btrfs_inode_timespec *
 490 btrfs_inode_atime(struct btrfs_inode_item *inode_item)
 491 {
 492         unsigned long ptr = (unsigned long)inode_item;
 493         ptr += offsetof(struct btrfs_inode_item, atime);
 494         return (struct btrfs_inode_timespec *)ptr;
 495 }
 496
 497 static inline struct btrfs_inode_timespec *
 498 btrfs_inode_mtime(struct btrfs_inode_item *inode_item)
 499 {
 500         unsigned long ptr = (unsigned long)inode_item;
 501         ptr += offsetof(struct btrfs_inode_item, mtime);
 502         return (struct btrfs_inode_timespec *)ptr;
 503 }
 504
 505 static inline struct btrfs_inode_timespec *
 506 btrfs_inode_ctime(struct btrfs_inode_item *inode_item)
 507 {
 508         unsigned long ptr = (unsigned long)inode_item;
 509         ptr += offsetof(struct btrfs_inode_item, ctime);
 510         return (struct btrfs_inode_timespec *)ptr;
 511 }
 512
 513 static inline struct btrfs_inode_timespec *
 514 btrfs_inode_otime(struct btrfs_inode_item *inode_item)
 515 {
 516         unsigned long ptr = (unsigned long)inode_item;
 517         ptr += offsetof(struct btrfs_inode_item, otime);
 518         return (struct btrfs_inode_timespec *)ptr;
 519 }
 520
 521 BTRFS_SETGET_FUNCS(timespec_sec, struct btrfs_inode_timespec, sec, 64);
 522 BTRFS_SETGET_FUNCS(timespec_nsec, struct btrfs_inode_timespec, nsec, 32);
 523
 524 /* struct btrfs_extent_item */
 525 BTRFS_SETGET_FUNCS(extent_refs, struct btrfs_extent_item, refs, 32);
 526 BTRFS_SETGET_FUNCS(extent_owner, struct btrfs_extent_item, owner, 32);
 527
 528 BTRFS_SETGET_STACK_FUNCS(stack_extent_refs, struct btrfs_extent_item,
 529                          refs, 32);
 530 BTRFS_SETGET_STACK_FUNCS(stack_extent_owner, struct btrfs_extent_item,
 531                          owner, 32);
 532
 533 /* struct btrfs_node */
 534 BTRFS_SETGET_FUNCS(key_blockptr, struct btrfs_key_ptr, blockptr, 64);
 535
 536 static inline u64 btrfs_node_blockptr(struct extent_buffer *eb, int nr)
 537 {
 538         unsigned long ptr;
 539         ptr = offsetof(struct btrfs_node, ptrs) +
 540                 sizeof(struct btrfs_key_ptr) * nr;
 541         return btrfs_key_blockptr(eb, (struct btrfs_key_ptr *)ptr);
 542 }
 543
 544 static inline void btrfs_set_node_blockptr(struct extent_buffer *eb,
 545                                            int nr, u64 val)
 546 {
 547         unsigned long ptr;
 548         ptr = offsetof(struct btrfs_node, ptrs) +
 549                 sizeof(struct btrfs_key_ptr) * nr;
 550         btrfs_set_key_blockptr(eb, (struct btrfs_key_ptr *)ptr, val);
 551 }
 552
 553 static unsigned long btrfs_node_key_ptr_offset(int nr)
 554 {
 555         return offsetof(struct btrfs_node, ptrs) +
 556                 sizeof(struct btrfs_key_ptr) * nr;
 557 }
 558
 559 static void btrfs_node_key(struct extent_buffer *eb,
 560                            struct btrfs_disk_key *disk_key, int nr)
 561 {
 562         unsigned long ptr;
 563         ptr = btrfs_node_key_ptr_offset(nr);
 564         read_eb_member(eb, (struct btrfs_key_ptr *)ptr,
 565                        struct btrfs_key_ptr, key, disk_key);
 566 }
 567 static inline void btrfs_set_node_key(struct extent_buffer *eb,
 568                                       struct btrfs_disk_key *disk_key, int nr)
 569 {
 570         unsigned long ptr;
 571         ptr = btrfs_node_key_ptr_offset(nr);
 572         write_eb_member(eb, (struct btrfs_key_ptr *)ptr,
 573                        struct btrfs_key_ptr, key, disk_key);
 574 }
 575
 576 /* struct btrfs_item */
 577 BTRFS_SETGET_FUNCS(item_offset, struct btrfs_item, offset, 32);
 578 BTRFS_SETGET_FUNCS(item_size, struct btrfs_item, size, 32);
 579
 580 static inline unsigned long btrfs_item_nr_offset(int nr)
 581 {
 582         return offsetof(struct btrfs_leaf, items) +
 583                 sizeof(struct btrfs_item) * nr;
 584 }
 585
 586 static inline struct btrfs_item *btrfs_item_nr(struct extent_buffer *eb,
 587                                                int nr)
 588 {
 589         return (struct btrfs_item *)btrfs_item_nr_offset(nr);
 590 }
 591
 592 static inline u32 btrfs_item_end(struct extent_buffer *eb,
 593                                  struct btrfs_item *item)
 594 {
 595         return btrfs_item_offset(eb, item) + btrfs_item_size(eb, item);
 596 }
 597
 598 static inline u32 btrfs_item_end_nr(struct extent_buffer *eb, int nr)
 599 {
 600         return btrfs_item_end(eb, btrfs_item_nr(eb, nr));
 601 }
 602
 603 static inline u32 btrfs_item_offset_nr(struct extent_buffer *eb, int nr)
 604 {
 605         return btrfs_item_offset(eb, btrfs_item_nr(eb, nr));
 606 }
 607
 608 static inline u32 btrfs_item_size_nr(struct extent_buffer *eb, int nr)
 609 {
 610         return btrfs_item_size(eb, btrfs_item_nr(eb, nr));
 611 }
 612
 613 static inline void btrfs_item_key(struct extent_buffer *eb,
 614                            struct btrfs_disk_key *disk_key, int nr)
 615 {
 616         struct btrfs_item *item = btrfs_item_nr(eb, nr);
 617         read_eb_member(eb, item, struct btrfs_item, key, disk_key);
 618 }
 619
 620 static inline void btrfs_set_item_key(struct extent_buffer *eb,
 621                                struct btrfs_disk_key *disk_key, int nr)
 622 {
 623         struct btrfs_item *item = btrfs_item_nr(eb, nr);
 624         write_eb_member(eb, item, struct btrfs_item, key, disk_key);
 625 }
 626
 627 /* struct btrfs_dir_item */
 628 BTRFS_SETGET_FUNCS(dir_flags, struct btrfs_dir_item, flags, 16);
 629 BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8);
 630 BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16);
 631
 632 static inline void btrfs_dir_item_key(struct extent_buffer *eb,
 633                                       struct btrfs_dir_item *item,
 634                                       struct btrfs_disk_key *key)
 635 {
 636         read_eb_member(eb, item, struct btrfs_dir_item, location, key);
 637 }
 638
 639 static inline void btrfs_set_dir_item_key(struct extent_buffer *eb,
 640                                           struct btrfs_dir_item *item,
 641                                           struct btrfs_disk_key *key)
 642 {
 643         write_eb_member(eb, item, struct btrfs_dir_item, location, key);
 644 }
 645
 646 /* struct btrfs_disk_key */
 647 BTRFS_SETGET_STACK_FUNCS(disk_key_objectid, struct btrfs_disk_key,
 648                          objectid, 64);
 649 BTRFS_SETGET_STACK_FUNCS(disk_key_offset, struct btrfs_disk_key, offset, 64);
 650 BTRFS_SETGET_STACK_FUNCS(disk_key_type, struct btrfs_disk_key, type, 8);
 651
 652 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
 653                                          struct btrfs_disk_key *disk)
 654 {
 655         cpu->offset = le64_to_cpu(disk->offset);
 656         cpu->type = disk->type;
 657         cpu->objectid = le64_to_cpu(disk->objectid);
 658 }
 659
 660 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
 661                                          struct btrfs_key *cpu)
 662 {
 663         disk->offset = cpu_to_le64(cpu->offset);
 664         disk->type = cpu->type;
 665         disk->objectid = cpu_to_le64(cpu->objectid);
 666 }
 667
 668 static inline void btrfs_node_key_to_cpu(struct extent_buffer *eb,
 669                                   struct btrfs_key *key, int nr)
 670 {
 671         struct btrfs_disk_key disk_key;
 672         btrfs_node_key(eb, &disk_key, nr);
 673         btrfs_disk_key_to_cpu(key, &disk_key);
 674 }
 675
 676 static inline void btrfs_item_key_to_cpu(struct extent_buffer *eb,
 677                                   struct btrfs_key *key, int nr)
 678 {
 679         struct btrfs_disk_key disk_key;
 680         btrfs_item_key(eb, &disk_key, nr);
 681         btrfs_disk_key_to_cpu(key, &disk_key);
 682 }
 683
 684 static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb,
 685                                       struct btrfs_dir_item *item,
 686                                       struct btrfs_key *key)
 687 {
 688         struct btrfs_disk_key disk_key;
 689         btrfs_dir_item_key(eb, item, &disk_key);
 690         btrfs_disk_key_to_cpu(key, &disk_key);
 691 }
 692
 693
 694 static inline u8 btrfs_key_type(struct btrfs_key *key)
 695 {
 696         return key->type;
 697 }
 698
 699 static inline void btrfs_set_key_type(struct btrfs_key *key, u8 val)
 700 {
 701         key->type = val;
 702 }
 703
 704 /* struct btrfs_header */
 705 BTRFS_SETGET_HEADER_FUNCS(header_blocknr, struct btrfs_header, blocknr, 64);
 706 BTRFS_SETGET_HEADER_FUNCS(header_generation, struct btrfs_header,
 707                           generation, 64);
 708 BTRFS_SETGET_HEADER_FUNCS(header_owner, struct btrfs_header, owner, 64);
 709 BTRFS_SETGET_HEADER_FUNCS(header_nritems, struct btrfs_header, nritems, 32);
 710 BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 16);
 711 BTRFS_SETGET_HEADER_FUNCS(header_level, struct btrfs_header, level, 8);
 712
 713 static inline u8 *btrfs_header_fsid(struct extent_buffer *eb)
 714 {
 715         unsigned long ptr = offsetof(struct btrfs_header, fsid);
 716         return (u8 *)ptr;
 717 }
 718
 719 static inline u8 *btrfs_super_fsid(struct extent_buffer *eb)
 720 {
 721         unsigned long ptr = offsetof(struct btrfs_super_block, fsid);
 722         return (u8 *)ptr;
 723 }
 724
 725 static inline u8 *btrfs_header_csum(struct extent_buffer *eb)
 726 {
 727         unsigned long ptr = offsetof(struct btrfs_header, csum);
 728         return (u8 *)ptr;
 729 }
 730
 731 static inline struct btrfs_node *btrfs_buffer_node(struct extent_buffer *eb)
 732 {
 733         return NULL;
 734 }
 735
 736 static inline struct btrfs_leaf *btrfs_buffer_leaf(struct extent_buffer *eb)
 737 {
 738         return NULL;
 739 }
 740
 741 static inline struct btrfs_header *btrfs_buffer_header(struct extent_buffer *eb)
 742 {
 743         return NULL;
 744 }
 745
 746 static inline int btrfs_is_leaf(struct extent_buffer *eb)
 747 {
 748         return (btrfs_header_level(eb) == 0);
 749 }
 750
 751 /* struct btrfs_root_item */
 752 BTRFS_SETGET_FUNCS(disk_root_refs, struct btrfs_root_item, refs, 32);
 753 BTRFS_SETGET_FUNCS(disk_root_blocknr, struct btrfs_root_item, blocknr, 64);
 754
 755 BTRFS_SETGET_STACK_FUNCS(root_blocknr, struct btrfs_root_item, blocknr, 64);
 756 BTRFS_SETGET_STACK_FUNCS(root_dirid, struct btrfs_root_item, root_dirid, 64);
 757 BTRFS_SETGET_STACK_FUNCS(root_refs, struct btrfs_root_item, refs, 32);
 758 BTRFS_SETGET_STACK_FUNCS(root_flags, struct btrfs_root_item, flags, 32);
 759 BTRFS_SETGET_STACK_FUNCS(root_used, struct btrfs_root_item, blocks_used, 64);
 760 BTRFS_SETGET_STACK_FUNCS(root_limit, struct btrfs_root_item, block_limit, 64);
 761
 762 /* struct btrfs_super_block */
 763 BTRFS_SETGET_STACK_FUNCS(super_blocknr, struct btrfs_super_block, blocknr, 64);
 764 BTRFS_SETGET_STACK_FUNCS(super_generation, struct btrfs_super_block,
 765                          generation, 64);
 766 BTRFS_SETGET_STACK_FUNCS(super_root, struct btrfs_super_block, root, 64);
 767 BTRFS_SETGET_STACK_FUNCS(super_total_blocks, struct btrfs_super_block,
 768                    total_blocks, 64);
 769 BTRFS_SETGET_STACK_FUNCS(super_blocks_used, struct btrfs_super_block,
 770                    blocks_used, 64);
 771 BTRFS_SETGET_STACK_FUNCS(super_sectorsize, struct btrfs_super_block,
 772                          sectorsize, 32);
 773 BTRFS_SETGET_STACK_FUNCS(super_nodesize, struct btrfs_super_block,
 774                          nodesize, 32);
 775 BTRFS_SETGET_STACK_FUNCS(super_leafsize, struct btrfs_super_block,
 776                          leafsize, 32);
 777 BTRFS_SETGET_STACK_FUNCS(super_root_dir, struct btrfs_super_block,
 778                          root_dir_objectid, 64);
 779
 780 static inline unsigned long btrfs_leaf_data(struct extent_buffer *l)
 781 {
 782         return offsetof(struct btrfs_leaf, items);
 783 }
 784
 785 /* struct btrfs_file_extent_item */
 786 BTRFS_SETGET_FUNCS(file_extent_type, struct btrfs_file_extent_item, type, 8);
 787
 788 static inline unsigned long btrfs_file_extent_inline_start(struct
 789                                                    btrfs_file_extent_item *e)
 790 {
 791         unsigned long offset = (unsigned long)e;
 792         offset += offsetof(struct btrfs_file_extent_item, disk_blocknr);
 793         return offset;
 794 }
 795
 796 static inline u32 btrfs_file_extent_calc_inline_size(u32 datasize)
 797 {
 798         return offsetof(struct btrfs_file_extent_item, disk_blocknr) + datasize;
 799 }
 800
 801 static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb,
 802                                                struct btrfs_item *e)
 803 {
 804         unsigned long offset;
 805         offset = offsetof(struct btrfs_file_extent_item, disk_blocknr);
 806         return btrfs_item_size(eb, e) - offset;
 807 }
 808
 809 BTRFS_SETGET_FUNCS(file_extent_disk_blocknr, struct btrfs_file_extent_item,
 810                    disk_blocknr, 64);
 811 BTRFS_SETGET_FUNCS(file_extent_generation, struct btrfs_file_extent_item,
 812                    generation, 64);
 813 BTRFS_SETGET_FUNCS(file_extent_disk_num_blocks, struct btrfs_file_extent_item,
 814                    disk_num_blocks, 64);
 815 BTRFS_SETGET_FUNCS(file_extent_offset, struct btrfs_file_extent_item,
 816                   offset, 64);
 817 BTRFS_SETGET_FUNCS(file_extent_num_blocks, struct btrfs_file_extent_item,
 818                    num_blocks, 64);
 819
 820 static inline struct btrfs_root *btrfs_sb(struct super_block *sb)
 821 {
 822         return sb->s_fs_info;
 823 }
 824
 825 static inline int btrfs_set_root_name(struct btrfs_root *root,
 826                                       const char *name, int len)
 827 {
 828         /* if we already have a name just free it */
 829         if (root->name)
 830                 kfree(root->name);
 831
 832         root->name = kmalloc(len+1, GFP_KERNEL);
 833         if (!root->name)
 834                 return -ENOMEM;
 835
 836         memcpy(root->name, name, len);
 837         root->name[len] ='\0';
 838
 839         return 0;
 840 }
 841
 842 /* helper function to cast into the data area of the leaf. */
 843 #define btrfs_item_ptr(leaf, slot, type) \
 844         ((type *)(btrfs_leaf_data(leaf) + \
 845         btrfs_item_offset_nr(leaf, slot)))
 846
 847 #define btrfs_item_ptr_offset(leaf, slot) \
 848         ((unsigned long)(btrfs_leaf_data(leaf) + \
 849         btrfs_item_offset_nr(leaf, slot)))
 850
 851 /* mount option defines and helpers */
 852 #define BTRFS_MOUNT_SUBVOL              0x000001
 853 #define btrfs_clear_opt(o, opt)         o &= ~BTRFS_MOUNT_##opt
 854 #define btrfs_set_opt(o, opt)           o |= BTRFS_MOUNT_##opt
 855 #define btrfs_test_opt(sb, opt)         (BTRFS_SB(sb)->s_mount_opt & \
 856                                          BTRFS_MOUNT_##opt)
 857 /* extent-tree.c */
 858 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
 859                          struct btrfs_root *root);
 860 int btrfs_copy_pinned(struct btrfs_root *root, struct radix_tree_root *copy);
 861 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
 862                                                          btrfs_fs_info *info,
 863                                                          u64 blocknr);
 864 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
 865                                                  struct btrfs_block_group_cache
 866                                                  *hint, u64 search_start,
 867                                                  int data, int owner);
 868 int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
 869                        struct btrfs_root *root);
 870 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 871                                             struct btrfs_root *root, u64 hint,
 872                                             u64 empty_size);
 873 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
 874                        struct btrfs_root *root, u64 owner,
 875                        u64 num_blocks, u64 empty_size, u64 search_start,
 876                        u64 search_end, struct btrfs_key *ins, int data);
 877 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 878                   struct extent_buffer *buf);
 879 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
 880                       *root, u64 blocknr, u64 num_blocks, int pin);
 881 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 882                                struct btrfs_root *root,
 883                                struct radix_tree_root *unpin_radix);
 884 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 885                                 struct btrfs_root *root,
 886                                 u64 blocknr, u64 num_blocks);
 887 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 888                                     struct btrfs_root *root);
 889 int btrfs_free_block_groups(struct btrfs_fs_info *info);
 890 int btrfs_read_block_groups(struct btrfs_root *root);
 891 /* ctree.c */
 892 int btrfs_cow_block(struct btrfs_trans_handle *trans,
 893                     struct btrfs_root *root, struct extent_buffer *buf,
 894                     struct extent_buffer *parent, int parent_slot,
 895                     struct extent_buffer **cow_ret);
 896 int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
 897                       *root, struct btrfs_path *path, u32 data_size);
 898 int btrfs_truncate_item(struct btrfs_trans_handle *trans,
 899                         struct btrfs_root *root,
 900                         struct btrfs_path *path,
 901                         u32 new_size);
 902 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
 903                       *root, struct btrfs_key *key, struct btrfs_path *p, int
 904                       ins_len, int cow);
 905 int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 906                        struct btrfs_root *root, struct extent_buffer *parent,
 907                        int cache_only, u64 *last_ret);
 908 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 909 struct btrfs_path *btrfs_alloc_path(void);
 910 void btrfs_free_path(struct btrfs_path *p);
 911 void btrfs_init_path(struct btrfs_path *p);
 912 int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 913                    struct btrfs_path *path);
 914 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
 915                       *root, struct btrfs_key *key, void *data, u32 data_size);
 916 int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root
 917                             *root, struct btrfs_path *path, struct btrfs_key
 918                             *cpu_key, u32 data_size);
 919 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
 920 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
 921 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
 922                         *root);
 923 /* root-item.c */
 924 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 925                    struct btrfs_key *key);
 926 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
 927                       *root, struct btrfs_key *key, struct btrfs_root_item
 928                       *item);
 929 int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
 930                       *root, struct btrfs_key *key, struct btrfs_root_item
 931                       *item);
 932 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
 933                          btrfs_root_item *item, struct btrfs_key *key);
 934 int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid,
 935                           struct btrfs_root *latest_root);
 936 /* dir-item.c */
 937 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 938                           *root, const char *name, int name_len, u64 dir,
 939                           struct btrfs_key *location, u8 type);
 940 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 941                                              struct btrfs_root *root,
 942                                              struct btrfs_path *path, u64 dir,
 943                                              const char *name, int name_len,
 944                                              int mod);
 945 struct btrfs_dir_item *
 946 btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
 947                             struct btrfs_root *root,
 948                             struct btrfs_path *path, u64 dir,
 949                             u64 objectid, const char *name, int name_len,
 950                             int mod);
 951 struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
 952                               struct btrfs_path *path,
 953                               const char *name, int name_len);
 954 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
 955                               struct btrfs_root *root,
 956                               struct btrfs_path *path,
 957                               struct btrfs_dir_item *di);
 958 /* inode-map.c */
 959 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
 960                              struct btrfs_root *fs_root,
 961                              u64 dirid, u64 *objectid);
 962 int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
 963
 964 /* inode-item.c */
 965 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
 966                              struct btrfs_root *root,
 967                              struct btrfs_path *path, u64 objectid);
 968 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
 969                        *root, struct btrfs_path *path,
 970                        struct btrfs_key *location, int mod);
 971
 972 /* file-item.c */
 973 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
 974                                struct btrfs_root *root,
 975                                u64 objectid, u64 pos, u64 offset,
 976                                u64 disk_num_blocks,
 977                                u64 num_blocks);
 978 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 979                              struct btrfs_root *root,
 980                              struct btrfs_path *path, u64 objectid,
 981                              u64 blocknr, int mod);
 982 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
 983                           struct btrfs_root *root,
 984                           u64 objectid, u64 offset,
 985                           char *data, size_t len);
 986 struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
 987                                           struct btrfs_root *root,
 988                                           struct btrfs_path *path,
 989                                           u64 objectid, u64 offset,
 990                                           int cow);
 991 int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
 992                         struct btrfs_root *root, struct btrfs_path *path,
 993                         u64 isize);
 994 /* inode.c */
 995 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page);
 996 int btrfs_readpage(struct file *file, struct page *page);
 997 void btrfs_delete_inode(struct inode *inode);
 998 void btrfs_read_locked_inode(struct inode *inode);
 999 int btrfs_write_inode(struct inode *inode, int wait);
1000 void btrfs_dirty_inode(struct inode *inode);
1001 struct inode *btrfs_alloc_inode(struct super_block *sb);
1002 void btrfs_destroy_inode(struct inode *inode);
1003 int btrfs_init_cachep(void);
1004 void btrfs_destroy_cachep(void);
1005 long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1006 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1007                                 struct btrfs_root *root);
1008 int btrfs_commit_write(struct file *file, struct page *page,
1009                        unsigned from, unsigned to);
1010 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1011                                     size_t page_offset, u64 start, u64 end,
1012                                     int create);
1013 int btrfs_update_inode(struct btrfs_trans_handle *trans,
1014                               struct btrfs_root *root,
1015                               struct inode *inode);
1016 /* file.c */
1017 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end);
1018 extern struct file_operations btrfs_file_operations;
1019 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
1020                        struct btrfs_root *root, struct inode *inode,
1021                        u64 start, u64 end, u64 *hint_block);
1022 /* tree-defrag.c */
1023 int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
1024                         struct btrfs_root *root, int cache_only);
1025
1026 /* sysfs.c */
1027 int btrfs_init_sysfs(void);
1028 void btrfs_exit_sysfs(void);
1029 int btrfs_sysfs_add_super(struct btrfs_fs_info *fs);
1030 int btrfs_sysfs_add_root(struct btrfs_root *root);
1031 void btrfs_sysfs_del_root(struct btrfs_root *root);
1032 void btrfs_sysfs_del_super(struct btrfs_fs_info *root);
1033
1034 #endif