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/mm.h>
  23 #include <linux/highmem.h>
  24 #include <linux/fs.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/completion.h>
  27 #include <asm/kmap_types.h>
  28 #include "bit-radix.h"
  29 #include "extent_map.h"
  30
  31 struct btrfs_trans_handle;
  32 struct btrfs_transaction;
  33 extern struct kmem_cache *btrfs_trans_handle_cachep;
  34 extern struct kmem_cache *btrfs_transaction_cachep;
  35 extern struct kmem_cache *btrfs_bit_radix_cachep;
  36 extern struct kmem_cache *btrfs_path_cachep;
  37
  38 #define BTRFS_MAGIC "_B2RfS_M"
  39
  40 #define BTRFS_ROOT_TREE_OBJECTID 1ULL
  41 #define BTRFS_EXTENT_TREE_OBJECTID 2ULL
  42 #define BTRFS_FS_TREE_OBJECTID 3ULL
  43 #define BTRFS_ROOT_TREE_DIR_OBJECTID 4ULL
  44 #define BTRFS_FIRST_FREE_OBJECTID 5ULL
  45
  46 /*
  47  * we can actually store much bigger names, but lets not confuse the rest
  48  * of linux
  49  */
  50 #define BTRFS_NAME_LEN 255
  51
  52 /* 32 bytes in various csum fields */
  53 #define BTRFS_CSUM_SIZE 32
  54 /* four bytes for CRC32 */
  55 #define BTRFS_CRC32_SIZE 4
  56 #define BTRFS_EMPTY_DIR_SIZE 6
  57
  58 #define BTRFS_FT_UNKNOWN        0
  59 #define BTRFS_FT_REG_FILE       1
  60 #define BTRFS_FT_DIR            2
  61 #define BTRFS_FT_CHRDEV         3
  62 #define BTRFS_FT_BLKDEV         4
  63 #define BTRFS_FT_FIFO           5
  64 #define BTRFS_FT_SOCK           6
  65 #define BTRFS_FT_SYMLINK        7
  66 #define BTRFS_FT_XATTR          8
  67 #define BTRFS_FT_MAX            9
  68
  69 /*
  70  * the key defines the order in the tree, and so it also defines (optimal)
  71  * block layout.  objectid corresonds to the inode number.  The flags
  72  * tells us things about the object, and is a kind of stream selector.
  73  * so for a given inode, keys with flags of 1 might refer to the inode
  74  * data, flags of 2 may point to file data in the btree and flags == 3
  75  * may point to extents.
  76  *
  77  * offset is the starting byte offset for this key in the stream.
  78  *
  79  * btrfs_disk_key is in disk byte order.  struct btrfs_key is always
  80  * in cpu native order.  Otherwise they are identical and their sizes
  81  * should be the same (ie both packed)
  82  */
  83 struct btrfs_disk_key {
  84         __le64 objectid;
  85         u8 type;
  86         __le64 offset;
  87 } __attribute__ ((__packed__));
  88
  89 struct btrfs_key {
  90         u64 objectid;
  91         u8 type;
  92         u64 offset;
  93 } __attribute__ ((__packed__));
  94
  95 #define BTRFS_FSID_SIZE 16
  96 /*
  97  * every tree block (leaf or node) starts with this header.
  98  */
  99 struct btrfs_header {
 100         u8 csum[BTRFS_CSUM_SIZE];
 101         u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
 102         __le64 bytenr; /* which block this node is supposed to live in */
 103         __le64 generation;
 104         __le64 owner;
 105         __le32 nritems;
 106         __le16 flags;
 107         u8 level;
 108 } __attribute__ ((__packed__));
 109
 110 #define BTRFS_MAX_LEVEL 8
 111 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
 112                                 sizeof(struct btrfs_header)) / \
 113                                (sizeof(struct btrfs_disk_key) + sizeof(u64)))
 114 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
 115 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
 116 #define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
 117                                         sizeof(struct btrfs_item) - \
 118                                         sizeof(struct btrfs_file_extent_item))
 119
 120 /*
 121  * the super block basically lists the main trees of the FS
 122  * it currently lacks any block count etc etc
 123  */
 124 struct btrfs_super_block {
 125         u8 csum[BTRFS_CSUM_SIZE];
 126         /* the first 3 fields must match struct btrfs_header */
 127         u8 fsid[16];    /* FS specific uuid */
 128         __le64 bytenr; /* this block number */
 129         __le64 magic;
 130         __le64 generation;
 131         __le64 root;
 132         __le64 total_bytes;
 133         __le64 bytes_used;
 134         __le64 root_dir_objectid;
 135         __le32 sectorsize;
 136         __le32 nodesize;
 137         __le32 leafsize;
 138         u8 root_level;
 139 } __attribute__ ((__packed__));
 140
 141 /*
 142  * A leaf is full of items. offset and size tell us where to find
 143  * the item in the leaf (relative to the start of the data area)
 144  */
 145 struct btrfs_item {
 146         struct btrfs_disk_key key;
 147         __le32 offset;
 148         __le32 size;
 149 } __attribute__ ((__packed__));
 150
 151 /*
 152  * leaves have an item area and a data area:
 153  * [item0, item1....itemN] [free space] [dataN...data1, data0]
 154  *
 155  * The data is separate from the items to get the keys closer together
 156  * during searches.
 157  */
 158 struct btrfs_leaf {
 159         struct btrfs_header header;
 160         struct btrfs_item items[];
 161 } __attribute__ ((__packed__));
 162
 163 /*
 164  * all non-leaf blocks are nodes, they hold only keys and pointers to
 165  * other blocks
 166  */
 167 struct btrfs_key_ptr {
 168         struct btrfs_disk_key key;
 169         __le64 blockptr;
 170 } __attribute__ ((__packed__));
 171
 172 struct btrfs_node {
 173         struct btrfs_header header;
 174         struct btrfs_key_ptr ptrs[];
 175 } __attribute__ ((__packed__));
 176
 177 /*
 178  * btrfs_paths remember the path taken from the root down to the leaf.
 179  * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
 180  * to any other levels that are present.
 181  *
 182  * The slots array records the index of the item or block pointer
 183  * used while walking the tree.
 184  */
 185 struct btrfs_path {
 186         struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
 187         int slots[BTRFS_MAX_LEVEL];
 188         int reada;
 189         int lowest_level;
 190 };
 191
 192 /*
 193  * items in the extent btree are used to record the objectid of the
 194  * owner of the block and the number of references
 195  */
 196 struct btrfs_extent_item {
 197         __le32 refs;
 198         __le64 owner;
 199 } __attribute__ ((__packed__));
 200
 201 struct btrfs_inode_timespec {
 202         __le64 sec;
 203         __le32 nsec;
 204 } __attribute__ ((__packed__));
 205
 206 /*
 207  * there is no padding here on purpose.  If you want to extent the inode,
 208  * make a new item type
 209  */
 210 struct btrfs_inode_item {
 211         __le64 generation;
 212         __le64 size;
 213         __le64 nblocks;
 214         __le64 block_group;
 215         __le32 nlink;
 216         __le32 uid;
 217         __le32 gid;
 218         __le32 mode;
 219         __le32 rdev;
 220         __le16 flags;
 221         __le16 compat_flags;
 222         struct btrfs_inode_timespec atime;
 223         struct btrfs_inode_timespec ctime;
 224         struct btrfs_inode_timespec mtime;
 225         struct btrfs_inode_timespec otime;
 226 } __attribute__ ((__packed__));
 227
 228 struct btrfs_dir_item {
 229         struct btrfs_disk_key location;
 230         __le16 data_len;
 231         __le16 name_len;
 232         u8 type;
 233 } __attribute__ ((__packed__));
 234
 235 struct btrfs_root_item {
 236         struct btrfs_inode_item inode;
 237         __le64 root_dirid;
 238         __le64 bytenr;
 239         __le64 byte_limit;
 240         __le64 bytes_used;
 241         __le32 flags;
 242         __le32 refs;
 243         struct btrfs_disk_key drop_progress;
 244         u8 drop_level;
 245         u8 level;
 246 } __attribute__ ((__packed__));
 247
 248 #define BTRFS_FILE_EXTENT_REG 0
 249 #define BTRFS_FILE_EXTENT_INLINE 1
 250
 251 struct btrfs_file_extent_item {
 252         __le64 generation;
 253         u8 type;
 254         /*
 255          * disk space consumed by the extent, checksum blocks are included
 256          * in these numbers
 257          */
 258         __le64 disk_bytenr;
 259         __le64 disk_num_bytes;
 260         /*
 261          * the logical offset in file blocks (no csums)
 262          * this extent record is for.  This allows a file extent to point
 263          * into the middle of an existing extent on disk, sharing it
 264          * between two snapshots (useful if some bytes in the middle of the
 265          * extent have changed
 266          */
 267         __le64 offset;
 268         /*
 269          * the logical number of file blocks (no csums included)
 270          */
 271         __le64 num_bytes;
 272 } __attribute__ ((__packed__));
 273
 274 struct btrfs_csum_item {
 275         u8 csum;
 276 } __attribute__ ((__packed__));
 277
 278 /* tag for the radix tree of block groups in ram */
 279 #define BTRFS_BLOCK_GROUP_SIZE (256 * 1024 * 1024)
 280
 281
 282 #define BTRFS_BLOCK_GROUP_DATA 1
 283 #define BTRFS_BLOCK_GROUP_MIXED 2
 284
 285 struct btrfs_block_group_item {
 286         __le64 used;
 287         u8 flags;
 288 } __attribute__ ((__packed__));
 289
 290 struct btrfs_block_group_cache {
 291         struct btrfs_key key;
 292         struct btrfs_block_group_item item;
 293         int data;
 294         int cached;
 295         u64 pinned;
 296 };
 297 struct btrfs_fs_info {
 298         u8 fsid[BTRFS_FSID_SIZE];
 299         struct btrfs_root *extent_root;
 300         struct btrfs_root *tree_root;
 301         struct radix_tree_root fs_roots_radix;
 302
 303         struct extent_map_tree free_space_cache;
 304         struct extent_map_tree block_group_cache;
 305         struct extent_map_tree pinned_extents;
 306         struct extent_map_tree pending_del;
 307         struct extent_map_tree extent_ins;
 308
 309         u64 generation;
 310         u64 last_trans_committed;
 311         struct btrfs_transaction *running_transaction;
 312         struct btrfs_super_block super_copy;
 313         struct extent_buffer *sb_buffer;
 314         struct super_block *sb;
 315         struct inode *btree_inode;
 316         spinlock_t hash_lock;
 317         struct mutex trans_mutex;
 318         struct mutex fs_mutex;
 319         struct list_head trans_list;
 320         struct list_head hashers;
 321         struct list_head dead_roots;
 322         struct delayed_work trans_work;
 323         struct kobject super_kobj;
 324         struct completion kobj_unregister;
 325         int do_barriers;
 326         int closing;
 327
 328         u64 total_pinned;
 329 };
 330 /*
 331  * in ram representation of the tree.  extent_root is used for all allocations
 332  * and for the extent tree extent_root root.
 333  */
 334 struct btrfs_root {
 335         struct extent_buffer *node;
 336         struct extent_buffer *commit_root;
 337         struct btrfs_root_item root_item;
 338         struct btrfs_key root_key;
 339         struct btrfs_fs_info *fs_info;
 340         struct inode *inode;
 341         struct kobject root_kobj;
 342         struct completion kobj_unregister;
 343         struct rw_semaphore snap_sem;
 344         u64 objectid;
 345         u64 last_trans;
 346
 347         /* data allocations are done in sectorsize units */
 348         u32 sectorsize;
 349
 350         /* node allocations are done in nodesize units */
 351         u32 nodesize;
 352
 353         /* leaf allocations are done in leafsize units */
 354         u32 leafsize;
 355
 356         u32 type;
 357         u64 highest_inode;
 358         u64 last_inode_alloc;
 359         int ref_cows;
 360         struct btrfs_key defrag_progress;
 361         int defrag_running;
 362         int defrag_level;
 363         char *name;
 364 };
 365
 366 /*
 367  * inode items have the data typically returned from stat and store other
 368  * info about object characteristics.  There is one for every file and dir in
 369  * the FS
 370  */
 371 #define BTRFS_INODE_ITEM_KEY            1
 372 #define BTRFS_XATTR_ITEM_KEY            2
 373 /* reserve 2-15 close to the inode for later flexibility */
 374
 375 /*
 376  * dir items are the name -> inode pointers in a directory.  There is one
 377  * for every name in a directory.
 378  */
 379 #define BTRFS_DIR_ITEM_KEY      16
 380 #define BTRFS_DIR_INDEX_KEY     17
 381 /*
 382  * extent data is for file data
 383  */
 384 #define BTRFS_EXTENT_DATA_KEY   18
 385 /*
 386  * csum items have the checksums for data in the extents
 387  */
 388 #define BTRFS_CSUM_ITEM_KEY     19
 389
 390 /* reserve 20-31 for other file stuff */
 391
 392 /*
 393  * root items point to tree roots.  There are typically in the root
 394  * tree used by the super block to find all the other trees
 395  */
 396 #define BTRFS_ROOT_ITEM_KEY     32
 397 /*
 398  * extent items are in the extent map tree.  These record which blocks
 399  * are used, and how many references there are to each block
 400  */
 401 #define BTRFS_EXTENT_ITEM_KEY   33
 402
 403 /*
 404  * block groups give us hints into the extent allocation trees.  Which
 405  * blocks are free etc etc
 406  */
 407 #define BTRFS_BLOCK_GROUP_ITEM_KEY 34
 408
 409 /*
 410  * string items are for debugging.  They just store a short string of
 411  * data in the FS
 412  */
 413 #define BTRFS_STRING_ITEM_KEY   253
 414
 415 /* some macros to generate set/get funcs for the struct fields.  This
 416  * assumes there is a lefoo_to_cpu for every type, so lets make a simple
 417  * one for u8:
 418  */
 419 #define le8_to_cpu(v) (v)
 420 #define cpu_to_le8(v) (v)
 421 #define __le8 u8
 422
 423 #define read_eb_member(eb, ptr, type, member, result) (                 \
 424         read_extent_buffer(eb, (char *)(result),                        \
 425                            ((unsigned long)(ptr)) +                     \
 426                             offsetof(type, member),                     \
 427                            sizeof(((type *)0)->member)))
 428
 429 #define write_eb_member(eb, ptr, type, member, result) (                \
 430         write_extent_buffer(eb, (char *)(result),                       \
 431                            ((unsigned long)(ptr)) +                     \
 432                             offsetof(type, member),                     \
 433                            sizeof(((type *)0)->member)))
 434
 435 #ifndef BTRFS_SETGET_FUNCS
 436 #define BTRFS_SETGET_FUNCS(name, type, member, bits)                    \
 437 u##bits btrfs_##name(struct extent_buffer *eb, type *s);                \
 438 void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val);
 439 #endif
 440
 441 #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits)             \
 442 static inline u##bits btrfs_##name(struct extent_buffer *eb)            \
 443 {                                                                       \
 444         char *kaddr = kmap_atomic(eb->first_page, KM_USER0);            \
 445         unsigned long offset = offsetof(type, member);                  \
 446         u##bits res;                                                    \
 447         __le##bits *tmp = (__le##bits *)(kaddr + offset);               \
 448         res = le##bits##_to_cpu(*tmp);                                  \
 449         kunmap_atomic(kaddr, KM_USER0);                                 \
 450         return res;                                                     \
 451 }                                                                       \
 452 static inline void btrfs_set_##name(struct extent_buffer *eb,           \
 453                                     u##bits val)                        \
 454 {                                                                       \
 455         char *kaddr = kmap_atomic(eb->first_page, KM_USER0);            \
 456         unsigned long offset = offsetof(type, member);                  \
 457         __le##bits *tmp = (__le##bits *)(kaddr + offset);               \
 458         *tmp = cpu_to_le##bits(val);                                    \
 459         kunmap_atomic(kaddr, KM_USER0);                                 \
 460 }
 461
 462 #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits)              \
 463 static inline u##bits btrfs_##name(type *s)                             \
 464 {                                                                       \
 465         return le##bits##_to_cpu(s->member);                            \
 466 }                                                                       \
 467 static inline void btrfs_set_##name(type *s, u##bits val)               \
 468 {                                                                       \
 469         s->member = cpu_to_le##bits(val);                               \
 470 }
 471
 472 /* struct btrfs_block_group_item */
 473 BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item,
 474                          used, 64);
 475 BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item,
 476                          used, 64);
 477
 478 /* struct btrfs_inode_item */
 479 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
 480 BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64);
 481 BTRFS_SETGET_FUNCS(inode_nblocks, struct btrfs_inode_item, nblocks, 64);
 482 BTRFS_SETGET_FUNCS(inode_block_group, struct btrfs_inode_item, block_group, 64);
 483 BTRFS_SETGET_FUNCS(inode_nlink, struct btrfs_inode_item, nlink, 32);
 484 BTRFS_SETGET_FUNCS(inode_uid, struct btrfs_inode_item, uid, 32);
 485 BTRFS_SETGET_FUNCS(inode_gid, struct btrfs_inode_item, gid, 32);
 486 BTRFS_SETGET_FUNCS(inode_mode, struct btrfs_inode_item, mode, 32);
 487 BTRFS_SETGET_FUNCS(inode_rdev, struct btrfs_inode_item, rdev, 32);
 488 BTRFS_SETGET_FUNCS(inode_flags, struct btrfs_inode_item, flags, 16);
 489 BTRFS_SETGET_FUNCS(inode_compat_flags, struct btrfs_inode_item,
 490                    compat_flags, 16);
 491
 492 static inline struct btrfs_inode_timespec *
 493 btrfs_inode_atime(struct btrfs_inode_item *inode_item)
 494 {
 495         unsigned long ptr = (unsigned long)inode_item;
 496         ptr += offsetof(struct btrfs_inode_item, atime);
 497         return (struct btrfs_inode_timespec *)ptr;
 498 }
 499
 500 static inline struct btrfs_inode_timespec *
 501 btrfs_inode_mtime(struct btrfs_inode_item *inode_item)
 502 {
 503         unsigned long ptr = (unsigned long)inode_item;
 504         ptr += offsetof(struct btrfs_inode_item, mtime);
 505         return (struct btrfs_inode_timespec *)ptr;
 506 }
 507
 508 static inline struct btrfs_inode_timespec *
 509 btrfs_inode_ctime(struct btrfs_inode_item *inode_item)
 510 {
 511         unsigned long ptr = (unsigned long)inode_item;
 512         ptr += offsetof(struct btrfs_inode_item, ctime);
 513         return (struct btrfs_inode_timespec *)ptr;
 514 }
 515
 516 static inline struct btrfs_inode_timespec *
 517 btrfs_inode_otime(struct btrfs_inode_item *inode_item)
 518 {
 519         unsigned long ptr = (unsigned long)inode_item;
 520         ptr += offsetof(struct btrfs_inode_item, otime);
 521         return (struct btrfs_inode_timespec *)ptr;
 522 }
 523
 524 BTRFS_SETGET_FUNCS(timespec_sec, struct btrfs_inode_timespec, sec, 64);
 525 BTRFS_SETGET_FUNCS(timespec_nsec, struct btrfs_inode_timespec, nsec, 32);
 526
 527 /* struct btrfs_extent_item */
 528 BTRFS_SETGET_FUNCS(extent_refs, struct btrfs_extent_item, refs, 32);
 529 BTRFS_SETGET_FUNCS(extent_owner, struct btrfs_extent_item, owner, 64);
 530
 531 BTRFS_SETGET_STACK_FUNCS(stack_extent_refs, struct btrfs_extent_item,
 532                          refs, 32);
 533 BTRFS_SETGET_STACK_FUNCS(stack_extent_owner, struct btrfs_extent_item,
 534                          owner, 64);
 535
 536 /* struct btrfs_node */
 537 BTRFS_SETGET_FUNCS(key_blockptr, struct btrfs_key_ptr, blockptr, 64);
 538
 539 static inline u64 btrfs_node_blockptr(struct extent_buffer *eb, int nr)
 540 {
 541         unsigned long ptr;
 542         ptr = offsetof(struct btrfs_node, ptrs) +
 543                 sizeof(struct btrfs_key_ptr) * nr;
 544         return btrfs_key_blockptr(eb, (struct btrfs_key_ptr *)ptr);
 545 }
 546
 547 static inline void btrfs_set_node_blockptr(struct extent_buffer *eb,
 548                                            int nr, u64 val)
 549 {
 550         unsigned long ptr;
 551         ptr = offsetof(struct btrfs_node, ptrs) +
 552                 sizeof(struct btrfs_key_ptr) * nr;
 553         btrfs_set_key_blockptr(eb, (struct btrfs_key_ptr *)ptr, val);
 554 }
 555
 556 static inline unsigned long btrfs_node_key_ptr_offset(int nr)
 557 {
 558         return offsetof(struct btrfs_node, ptrs) +
 559                 sizeof(struct btrfs_key_ptr) * nr;
 560 }
 561
 562 void btrfs_node_key(struct extent_buffer *eb,
 563                     struct btrfs_disk_key *disk_key, int nr);
 564
 565 static inline void btrfs_set_node_key(struct extent_buffer *eb,
 566                                       struct btrfs_disk_key *disk_key, int nr)
 567 {
 568         unsigned long ptr;
 569         ptr = btrfs_node_key_ptr_offset(nr);
 570         write_eb_member(eb, (struct btrfs_key_ptr *)ptr,
 571                        struct btrfs_key_ptr, key, disk_key);
 572 }
 573
 574 /* struct btrfs_item */
 575 BTRFS_SETGET_FUNCS(item_offset, struct btrfs_item, offset, 32);
 576 BTRFS_SETGET_FUNCS(item_size, struct btrfs_item, size, 32);
 577
 578 static inline unsigned long btrfs_item_nr_offset(int nr)
 579 {
 580         return offsetof(struct btrfs_leaf, items) +
 581                 sizeof(struct btrfs_item) * nr;
 582 }
 583
 584 static inline struct btrfs_item *btrfs_item_nr(struct extent_buffer *eb,
 585                                                int nr)
 586 {
 587         return (struct btrfs_item *)btrfs_item_nr_offset(nr);
 588 }
 589
 590 static inline u32 btrfs_item_end(struct extent_buffer *eb,
 591                                  struct btrfs_item *item)
 592 {
 593         return btrfs_item_offset(eb, item) + btrfs_item_size(eb, item);
 594 }
 595
 596 static inline u32 btrfs_item_end_nr(struct extent_buffer *eb, int nr)
 597 {
 598         return btrfs_item_end(eb, btrfs_item_nr(eb, nr));
 599 }
 600
 601 static inline u32 btrfs_item_offset_nr(struct extent_buffer *eb, int nr)
 602 {
 603         return btrfs_item_offset(eb, btrfs_item_nr(eb, nr));
 604 }
 605
 606 static inline u32 btrfs_item_size_nr(struct extent_buffer *eb, int nr)
 607 {
 608         return btrfs_item_size(eb, btrfs_item_nr(eb, nr));
 609 }
 610
 611 static inline void btrfs_item_key(struct extent_buffer *eb,
 612                            struct btrfs_disk_key *disk_key, int nr)
 613 {
 614         struct btrfs_item *item = btrfs_item_nr(eb, nr);
 615         read_eb_member(eb, item, struct btrfs_item, key, disk_key);
 616 }
 617
 618 static inline void btrfs_set_item_key(struct extent_buffer *eb,
 619                                struct btrfs_disk_key *disk_key, int nr)
 620 {
 621         struct btrfs_item *item = btrfs_item_nr(eb, nr);
 622         write_eb_member(eb, item, struct btrfs_item, key, disk_key);
 623 }
 624
 625 /* struct btrfs_dir_item */
 626 BTRFS_SETGET_FUNCS(dir_data_len, struct btrfs_dir_item, data_len, 16);
 627 BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8);
 628 BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16);
 629
 630 static inline void btrfs_dir_item_key(struct extent_buffer *eb,
 631                                       struct btrfs_dir_item *item,
 632                                       struct btrfs_disk_key *key)
 633 {
 634         read_eb_member(eb, item, struct btrfs_dir_item, location, key);
 635 }
 636
 637 static inline void btrfs_set_dir_item_key(struct extent_buffer *eb,
 638                                           struct btrfs_dir_item *item,
 639                                           struct btrfs_disk_key *key)
 640 {
 641         write_eb_member(eb, item, struct btrfs_dir_item, location, key);
 642 }
 643
 644 /* struct btrfs_disk_key */
 645 BTRFS_SETGET_STACK_FUNCS(disk_key_objectid, struct btrfs_disk_key,
 646                          objectid, 64);
 647 BTRFS_SETGET_STACK_FUNCS(disk_key_offset, struct btrfs_disk_key, offset, 64);
 648 BTRFS_SETGET_STACK_FUNCS(disk_key_type, struct btrfs_disk_key, type, 8);
 649
 650 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
 651                                          struct btrfs_disk_key *disk)
 652 {
 653         cpu->offset = le64_to_cpu(disk->offset);
 654         cpu->type = disk->type;
 655         cpu->objectid = le64_to_cpu(disk->objectid);
 656 }
 657
 658 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
 659                                          struct btrfs_key *cpu)
 660 {
 661         disk->offset = cpu_to_le64(cpu->offset);
 662         disk->type = cpu->type;
 663         disk->objectid = cpu_to_le64(cpu->objectid);
 664 }
 665
 666 static inline void btrfs_node_key_to_cpu(struct extent_buffer *eb,
 667                                   struct btrfs_key *key, int nr)
 668 {
 669         struct btrfs_disk_key disk_key;
 670         btrfs_node_key(eb, &disk_key, nr);
 671         btrfs_disk_key_to_cpu(key, &disk_key);
 672 }
 673
 674 static inline void btrfs_item_key_to_cpu(struct extent_buffer *eb,
 675                                   struct btrfs_key *key, int nr)
 676 {
 677         struct btrfs_disk_key disk_key;
 678         btrfs_item_key(eb, &disk_key, nr);
 679         btrfs_disk_key_to_cpu(key, &disk_key);
 680 }
 681
 682 static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb,
 683                                       struct btrfs_dir_item *item,
 684                                       struct btrfs_key *key)
 685 {
 686         struct btrfs_disk_key disk_key;
 687         btrfs_dir_item_key(eb, item, &disk_key);
 688         btrfs_disk_key_to_cpu(key, &disk_key);
 689 }
 690
 691
 692 static inline u8 btrfs_key_type(struct btrfs_key *key)
 693 {
 694         return key->type;
 695 }
 696
 697 static inline void btrfs_set_key_type(struct btrfs_key *key, u8 val)
 698 {
 699         key->type = val;
 700 }
 701
 702 /* struct btrfs_header */
 703 BTRFS_SETGET_HEADER_FUNCS(header_bytenr, struct btrfs_header, bytenr, 64);
 704 BTRFS_SETGET_HEADER_FUNCS(header_generation, struct btrfs_header,
 705                           generation, 64);
 706 BTRFS_SETGET_HEADER_FUNCS(header_owner, struct btrfs_header, owner, 64);
 707 BTRFS_SETGET_HEADER_FUNCS(header_nritems, struct btrfs_header, nritems, 32);
 708 BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 16);
 709 BTRFS_SETGET_HEADER_FUNCS(header_level, struct btrfs_header, level, 8);
 710
 711 static inline u8 *btrfs_header_fsid(struct extent_buffer *eb)
 712 {
 713         unsigned long ptr = offsetof(struct btrfs_header, fsid);
 714         return (u8 *)ptr;
 715 }
 716
 717 static inline u8 *btrfs_super_fsid(struct extent_buffer *eb)
 718 {
 719         unsigned long ptr = offsetof(struct btrfs_super_block, fsid);
 720         return (u8 *)ptr;
 721 }
 722
 723 static inline u8 *btrfs_header_csum(struct extent_buffer *eb)
 724 {
 725         unsigned long ptr = offsetof(struct btrfs_header, csum);
 726         return (u8 *)ptr;
 727 }
 728
 729 static inline struct btrfs_node *btrfs_buffer_node(struct extent_buffer *eb)
 730 {
 731         return NULL;
 732 }
 733
 734 static inline struct btrfs_leaf *btrfs_buffer_leaf(struct extent_buffer *eb)
 735 {
 736         return NULL;
 737 }
 738
 739 static inline struct btrfs_header *btrfs_buffer_header(struct extent_buffer *eb)
 740 {
 741         return NULL;
 742 }
 743
 744 static inline int btrfs_is_leaf(struct extent_buffer *eb)
 745 {
 746         return (btrfs_header_level(eb) == 0);
 747 }
 748
 749 /* struct btrfs_root_item */
 750 BTRFS_SETGET_FUNCS(disk_root_refs, struct btrfs_root_item, refs, 32);
 751 BTRFS_SETGET_FUNCS(disk_root_bytenr, struct btrfs_root_item, bytenr, 64);
 752 BTRFS_SETGET_FUNCS(disk_root_level, struct btrfs_root_item, level, 8);
 753
 754 BTRFS_SETGET_STACK_FUNCS(root_bytenr, struct btrfs_root_item, bytenr, 64);
 755 BTRFS_SETGET_STACK_FUNCS(root_level, struct btrfs_root_item, level, 8);
 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, bytes_used, 64);
 760 BTRFS_SETGET_STACK_FUNCS(root_limit, struct btrfs_root_item, byte_limit, 64);
 761
 762 /* struct btrfs_super_block */
 763 BTRFS_SETGET_STACK_FUNCS(super_bytenr, struct btrfs_super_block, bytenr, 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_root_level, struct btrfs_super_block,
 768                          root_level, 8);
 769 BTRFS_SETGET_STACK_FUNCS(super_total_bytes, struct btrfs_super_block,
 770                          total_bytes, 64);
 771 BTRFS_SETGET_STACK_FUNCS(super_bytes_used, struct btrfs_super_block,
 772                          bytes_used, 64);
 773 BTRFS_SETGET_STACK_FUNCS(super_sectorsize, struct btrfs_super_block,
 774                          sectorsize, 32);
 775 BTRFS_SETGET_STACK_FUNCS(super_nodesize, struct btrfs_super_block,
 776                          nodesize, 32);
 777 BTRFS_SETGET_STACK_FUNCS(super_leafsize, struct btrfs_super_block,
 778                          leafsize, 32);
 779 BTRFS_SETGET_STACK_FUNCS(super_root_dir, struct btrfs_super_block,
 780                          root_dir_objectid, 64);
 781
 782 static inline unsigned long btrfs_leaf_data(struct extent_buffer *l)
 783 {
 784         return offsetof(struct btrfs_leaf, items);
 785 }
 786
 787 /* struct btrfs_file_extent_item */
 788 BTRFS_SETGET_FUNCS(file_extent_type, struct btrfs_file_extent_item, type, 8);
 789
 790 static inline unsigned long btrfs_file_extent_inline_start(struct
 791                                                    btrfs_file_extent_item *e)
 792 {
 793         unsigned long offset = (unsigned long)e;
 794         offset += offsetof(struct btrfs_file_extent_item, disk_bytenr);
 795         return offset;
 796 }
 797
 798 static inline u32 btrfs_file_extent_calc_inline_size(u32 datasize)
 799 {
 800         return offsetof(struct btrfs_file_extent_item, disk_bytenr) + datasize;
 801 }
 802
 803 static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb,
 804                                                struct btrfs_item *e)
 805 {
 806         unsigned long offset;
 807         offset = offsetof(struct btrfs_file_extent_item, disk_bytenr);
 808         return btrfs_item_size(eb, e) - offset;
 809 }
 810
 811 BTRFS_SETGET_FUNCS(file_extent_disk_bytenr, struct btrfs_file_extent_item,
 812                    disk_bytenr, 64);
 813 BTRFS_SETGET_FUNCS(file_extent_generation, struct btrfs_file_extent_item,
 814                    generation, 64);
 815 BTRFS_SETGET_FUNCS(file_extent_disk_num_bytes, struct btrfs_file_extent_item,
 816                    disk_num_bytes, 64);
 817 BTRFS_SETGET_FUNCS(file_extent_offset, struct btrfs_file_extent_item,
 818                   offset, 64);
 819 BTRFS_SETGET_FUNCS(file_extent_num_bytes, struct btrfs_file_extent_item,
 820                    num_bytes, 64);
 821
 822 static inline struct btrfs_root *btrfs_sb(struct super_block *sb)
 823 {
 824         return sb->s_fs_info;
 825 }
 826
 827 static inline int btrfs_set_root_name(struct btrfs_root *root,
 828                                       const char *name, int len)
 829 {
 830         /* if we already have a name just free it */
 831         if (root->name)
 832                 kfree(root->name);
 833
 834         root->name = kmalloc(len+1, GFP_KERNEL);
 835         if (!root->name)
 836                 return -ENOMEM;
 837
 838         memcpy(root->name, name, len);
 839         root->name[len] ='\0';
 840
 841         return 0;
 842 }
 843
 844 static inline u32 btrfs_level_size(struct btrfs_root *root, int level) {
 845         if (level == 0)
 846                 return root->leafsize;
 847         return root->nodesize;
 848 }
 849
 850 /* helper function to cast into the data area of the leaf. */
 851 #define btrfs_item_ptr(leaf, slot, type) \
 852         ((type *)(btrfs_leaf_data(leaf) + \
 853         btrfs_item_offset_nr(leaf, slot)))
 854
 855 #define btrfs_item_ptr_offset(leaf, slot) \
 856         ((unsigned long)(btrfs_leaf_data(leaf) + \
 857         btrfs_item_offset_nr(leaf, slot)))
 858
 859 /* mount option defines and helpers */
 860 #define BTRFS_MOUNT_SUBVOL              0x000001
 861 #define btrfs_clear_opt(o, opt)         o &= ~BTRFS_MOUNT_##opt
 862 #define btrfs_set_opt(o, opt)           o |= BTRFS_MOUNT_##opt
 863 #define btrfs_test_opt(sb, opt)         (BTRFS_SB(sb)->s_mount_opt & \
 864                                          BTRFS_MOUNT_##opt)
 865 /* extent-tree.c */
 866 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
 867                          struct btrfs_root *root);
 868 int btrfs_copy_pinned(struct btrfs_root *root, struct extent_map_tree *copy);
 869 struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
 870                                                          btrfs_fs_info *info,
 871                                                          u64 bytenr);
 872 struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
 873                                                  struct btrfs_block_group_cache
 874                                                  *hint, u64 search_start,
 875                                                  int data, int owner);
 876 int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
 877                        struct btrfs_root *root);
 878 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
 879                                             struct btrfs_root *root, u32 size,
 880                                             u64 hint, u64 empty_size);
 881 int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
 882                        struct btrfs_root *root, u64 owner,
 883                        u64 num_bytes, u64 empty_size, u64 search_start,
 884                        u64 search_end, struct btrfs_key *ins, int data);
 885 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 886                   struct extent_buffer *buf);
 887 int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
 888                       *root, u64 bytenr, u64 num_bytes, int pin);
 889 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 890                                struct btrfs_root *root,
 891                                struct extent_map_tree *unpin);
 892 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
 893                                 struct btrfs_root *root,
 894                                 u64 bytenr, u64 num_bytes);
 895 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
 896                                     struct btrfs_root *root);
 897 int btrfs_free_block_groups(struct btrfs_fs_info *info);
 898 int btrfs_read_block_groups(struct btrfs_root *root);
 899 /* ctree.c */
 900 int btrfs_cow_block(struct btrfs_trans_handle *trans,
 901                     struct btrfs_root *root, struct extent_buffer *buf,
 902                     struct extent_buffer *parent, int parent_slot,
 903                     struct extent_buffer **cow_ret);
 904 int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
 905                       *root, struct btrfs_path *path, u32 data_size);
 906 int btrfs_truncate_item(struct btrfs_trans_handle *trans,
 907                         struct btrfs_root *root,
 908                         struct btrfs_path *path,
 909                         u32 new_size, int from_end);
 910 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
 911                       *root, struct btrfs_key *key, struct btrfs_path *p, int
 912                       ins_len, int cow);
 913 int btrfs_realloc_node(struct btrfs_trans_handle *trans,
 914                        struct btrfs_root *root, struct extent_buffer *parent,
 915                        int start_slot, int cache_only, u64 *last_ret,
 916                        struct btrfs_key *progress);
 917 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 918 struct btrfs_path *btrfs_alloc_path(void);
 919 void btrfs_free_path(struct btrfs_path *p);
 920 void btrfs_init_path(struct btrfs_path *p);
 921 int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 922                    struct btrfs_path *path);
 923 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
 924                       *root, struct btrfs_key *key, void *data, u32 data_size);
 925 int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root
 926                             *root, struct btrfs_path *path, struct btrfs_key
 927                             *cpu_key, u32 data_size);
 928 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
 929 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
 930 int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
 931                         *root);
 932 /* root-item.c */
 933 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 934                    struct btrfs_key *key);
 935 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
 936                       *root, struct btrfs_key *key, struct btrfs_root_item
 937                       *item);
 938 int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
 939                       *root, struct btrfs_key *key, struct btrfs_root_item
 940                       *item);
 941 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
 942                          btrfs_root_item *item, struct btrfs_key *key);
 943 int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid,
 944                           struct btrfs_root *latest_root);
 945 /* dir-item.c */
 946 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 947                           *root, const char *name, int name_len, u64 dir,
 948                           struct btrfs_key *location, u8 type);
 949 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 950                                              struct btrfs_root *root,
 951                                              struct btrfs_path *path, u64 dir,
 952                                              const char *name, int name_len,
 953                                              int mod);
 954 struct btrfs_dir_item *
 955 btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
 956                             struct btrfs_root *root,
 957                             struct btrfs_path *path, u64 dir,
 958                             u64 objectid, const char *name, int name_len,
 959                             int mod);
 960 struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
 961                               struct btrfs_path *path,
 962                               const char *name, int name_len);
 963 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
 964                               struct btrfs_root *root,
 965                               struct btrfs_path *path,
 966                               struct btrfs_dir_item *di);
 967 int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
 968                             struct btrfs_root *root, const char *name,
 969                             u16 name_len, const void *data, u16 data_len,
 970                             u64 dir);
 971 struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
 972                                           struct btrfs_root *root,
 973                                           struct btrfs_path *path, u64 dir,
 974                                           const char *name, u16 name_len,
 975                                           int mod);
 976 /* inode-map.c */
 977 int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
 978                              struct btrfs_root *fs_root,
 979                              u64 dirid, u64 *objectid);
 980 int btrfs_find_highest_inode(struct btrfs_root *fs_root, u64 *objectid);
 981
 982 /* inode-item.c */
 983 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
 984                              struct btrfs_root *root,
 985                              struct btrfs_path *path, u64 objectid);
 986 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
 987                        *root, struct btrfs_path *path,
 988                        struct btrfs_key *location, int mod);
 989
 990 /* file-item.c */
 991 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
 992                                struct btrfs_root *root,
 993                                u64 objectid, u64 pos, u64 offset,
 994                                u64 disk_num_bytes,
 995                                u64 num_bytes);
 996 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 997                              struct btrfs_root *root,
 998                              struct btrfs_path *path, u64 objectid,
 999                              u64 bytenr, int mod);
1000 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
1001                           struct btrfs_root *root,
1002                           struct inode *inode,
1003                           u64 objectid, u64 offset,
1004                           char *data, size_t len);
1005 struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
1006                                           struct btrfs_root *root,
1007                                           struct btrfs_path *path,
1008                                           u64 objectid, u64 offset,
1009                                           int cow);
1010 int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
1011                         struct btrfs_root *root, struct btrfs_path *path,
1012                         u64 isize);
1013 /* inode.c */
1014 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page);
1015 int btrfs_readpage(struct file *file, struct page *page);
1016 void btrfs_delete_inode(struct inode *inode);
1017 void btrfs_read_locked_inode(struct inode *inode);
1018 int btrfs_write_inode(struct inode *inode, int wait);
1019 void btrfs_dirty_inode(struct inode *inode);
1020 struct inode *btrfs_alloc_inode(struct super_block *sb);
1021 void btrfs_destroy_inode(struct inode *inode);
1022 int btrfs_init_cachep(void);
1023 void btrfs_destroy_cachep(void);
1024 long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
1025 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1026                                 struct btrfs_root *root);
1027 int btrfs_commit_write(struct file *file, struct page *page,
1028                        unsigned from, unsigned to);
1029 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
1030                                     size_t page_offset, u64 start, u64 end,
1031                                     int create);
1032 int btrfs_update_inode(struct btrfs_trans_handle *trans,
1033                               struct btrfs_root *root,
1034                               struct inode *inode);
1035 /* file.c */
1036 int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end);
1037 extern struct file_operations btrfs_file_operations;
1038 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
1039                        struct btrfs_root *root, struct inode *inode,
1040                        u64 start, u64 end, u64 inline_end, u64 *hint_block);
1041 /* tree-defrag.c */
1042 int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
1043                         struct btrfs_root *root, int cache_only);
1044
1045 /* sysfs.c */
1046 int btrfs_init_sysfs(void);
1047 void btrfs_exit_sysfs(void);
1048 int btrfs_sysfs_add_super(struct btrfs_fs_info *fs);
1049 int btrfs_sysfs_add_root(struct btrfs_root *root);
1050 void btrfs_sysfs_del_root(struct btrfs_root *root);
1051 void btrfs_sysfs_del_super(struct btrfs_fs_info *root);
1052
1053 /* xattr.c */
1054 ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size);
1055 int btrfs_delete_xattrs(struct btrfs_trans_handle *trans,
1056                         struct btrfs_root *root, struct inode *inode);
1057 #endif