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