xref: /openbmc/linux/fs/btrfs/ctree.h (revision 06ed5c2b)
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_CTREE__
20 #define __BTRFS_CTREE__
21 
22 #include <linux/mm.h>
23 #include <linux/highmem.h>
24 #include <linux/fs.h>
25 #include <linux/rwsem.h>
26 #include <linux/semaphore.h>
27 #include <linux/completion.h>
28 #include <linux/backing-dev.h>
29 #include <linux/wait.h>
30 #include <linux/slab.h>
31 #include <linux/kobject.h>
32 #include <trace/events/btrfs.h>
33 #include <asm/kmap_types.h>
34 #include <linux/pagemap.h>
35 #include <linux/btrfs.h>
36 #include <linux/workqueue.h>
37 #include "extent_io.h"
38 #include "extent_map.h"
39 #include "async-thread.h"
40 
41 struct btrfs_trans_handle;
42 struct btrfs_transaction;
43 struct btrfs_pending_snapshot;
44 extern struct kmem_cache *btrfs_trans_handle_cachep;
45 extern struct kmem_cache *btrfs_transaction_cachep;
46 extern struct kmem_cache *btrfs_bit_radix_cachep;
47 extern struct kmem_cache *btrfs_path_cachep;
48 extern struct kmem_cache *btrfs_free_space_cachep;
49 struct btrfs_ordered_sum;
50 
51 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
52 #define STATIC noinline
53 #else
54 #define STATIC static noinline
55 #endif
56 
57 #define BTRFS_MAGIC 0x4D5F53665248425FULL /* ascii _BHRfS_M, no null */
58 
59 #define BTRFS_MAX_MIRRORS 3
60 
61 #define BTRFS_MAX_LEVEL 8
62 
63 #define BTRFS_COMPAT_EXTENT_TREE_V0
64 
65 /*
66  * files bigger than this get some pre-flushing when they are added
67  * to the ordered operations list.  That way we limit the total
68  * work done by the commit
69  */
70 #define BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT (8 * 1024 * 1024)
71 
72 /* holds pointers to all of the tree roots */
73 #define BTRFS_ROOT_TREE_OBJECTID 1ULL
74 
75 /* stores information about which extents are in use, and reference counts */
76 #define BTRFS_EXTENT_TREE_OBJECTID 2ULL
77 
78 /*
79  * chunk tree stores translations from logical -> physical block numbering
80  * the super block points to the chunk tree
81  */
82 #define BTRFS_CHUNK_TREE_OBJECTID 3ULL
83 
84 /*
85  * stores information about which areas of a given device are in use.
86  * one per device.  The tree of tree roots points to the device tree
87  */
88 #define BTRFS_DEV_TREE_OBJECTID 4ULL
89 
90 /* one per subvolume, storing files and directories */
91 #define BTRFS_FS_TREE_OBJECTID 5ULL
92 
93 /* directory objectid inside the root tree */
94 #define BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL
95 
96 /* holds checksums of all the data extents */
97 #define BTRFS_CSUM_TREE_OBJECTID 7ULL
98 
99 /* holds quota configuration and tracking */
100 #define BTRFS_QUOTA_TREE_OBJECTID 8ULL
101 
102 /* for storing items that use the BTRFS_UUID_KEY* types */
103 #define BTRFS_UUID_TREE_OBJECTID 9ULL
104 
105 /* for storing balance parameters in the root tree */
106 #define BTRFS_BALANCE_OBJECTID -4ULL
107 
108 /* orhpan objectid for tracking unlinked/truncated files */
109 #define BTRFS_ORPHAN_OBJECTID -5ULL
110 
111 /* does write ahead logging to speed up fsyncs */
112 #define BTRFS_TREE_LOG_OBJECTID -6ULL
113 #define BTRFS_TREE_LOG_FIXUP_OBJECTID -7ULL
114 
115 /* for space balancing */
116 #define BTRFS_TREE_RELOC_OBJECTID -8ULL
117 #define BTRFS_DATA_RELOC_TREE_OBJECTID -9ULL
118 
119 /*
120  * extent checksums all have this objectid
121  * this allows them to share the logging tree
122  * for fsyncs
123  */
124 #define BTRFS_EXTENT_CSUM_OBJECTID -10ULL
125 
126 /* For storing free space cache */
127 #define BTRFS_FREE_SPACE_OBJECTID -11ULL
128 
129 /*
130  * The inode number assigned to the special inode for storing
131  * free ino cache
132  */
133 #define BTRFS_FREE_INO_OBJECTID -12ULL
134 
135 /* dummy objectid represents multiple objectids */
136 #define BTRFS_MULTIPLE_OBJECTIDS -255ULL
137 
138 /*
139  * All files have objectids in this range.
140  */
141 #define BTRFS_FIRST_FREE_OBJECTID 256ULL
142 #define BTRFS_LAST_FREE_OBJECTID -256ULL
143 #define BTRFS_FIRST_CHUNK_TREE_OBJECTID 256ULL
144 
145 
146 /*
147  * the device items go into the chunk tree.  The key is in the form
148  * [ 1 BTRFS_DEV_ITEM_KEY device_id ]
149  */
150 #define BTRFS_DEV_ITEMS_OBJECTID 1ULL
151 
152 #define BTRFS_BTREE_INODE_OBJECTID 1
153 
154 #define BTRFS_EMPTY_SUBVOL_DIR_OBJECTID 2
155 
156 #define BTRFS_DEV_REPLACE_DEVID 0ULL
157 
158 /*
159  * the max metadata block size.  This limit is somewhat artificial,
160  * but the memmove costs go through the roof for larger blocks.
161  */
162 #define BTRFS_MAX_METADATA_BLOCKSIZE 65536
163 
164 /*
165  * we can actually store much bigger names, but lets not confuse the rest
166  * of linux
167  */
168 #define BTRFS_NAME_LEN 255
169 
170 /*
171  * Theoretical limit is larger, but we keep this down to a sane
172  * value. That should limit greatly the possibility of collisions on
173  * inode ref items.
174  */
175 #define BTRFS_LINK_MAX 65535U
176 
177 /* 32 bytes in various csum fields */
178 #define BTRFS_CSUM_SIZE 32
179 
180 /* csum types */
181 #define BTRFS_CSUM_TYPE_CRC32	0
182 
183 static int btrfs_csum_sizes[] = { 4, 0 };
184 
185 /* four bytes for CRC32 */
186 #define BTRFS_EMPTY_DIR_SIZE 0
187 
188 /* spefic to btrfs_map_block(), therefore not in include/linux/blk_types.h */
189 #define REQ_GET_READ_MIRRORS	(1 << 30)
190 
191 #define BTRFS_FT_UNKNOWN	0
192 #define BTRFS_FT_REG_FILE	1
193 #define BTRFS_FT_DIR		2
194 #define BTRFS_FT_CHRDEV		3
195 #define BTRFS_FT_BLKDEV		4
196 #define BTRFS_FT_FIFO		5
197 #define BTRFS_FT_SOCK		6
198 #define BTRFS_FT_SYMLINK	7
199 #define BTRFS_FT_XATTR		8
200 #define BTRFS_FT_MAX		9
201 
202 /* ioprio of readahead is set to idle */
203 #define BTRFS_IOPRIO_READA (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0))
204 
205 #define BTRFS_DIRTY_METADATA_THRESH	(32 * 1024 * 1024)
206 
207 /*
208  * The key defines the order in the tree, and so it also defines (optimal)
209  * block layout.
210  *
211  * objectid corresponds to the inode number.
212  *
213  * type tells us things about the object, and is a kind of stream selector.
214  * so for a given inode, keys with type of 1 might refer to the inode data,
215  * type of 2 may point to file data in the btree and type == 3 may point to
216  * extents.
217  *
218  * offset is the starting byte offset for this key in the stream.
219  *
220  * btrfs_disk_key is in disk byte order.  struct btrfs_key is always
221  * in cpu native order.  Otherwise they are identical and their sizes
222  * should be the same (ie both packed)
223  */
224 struct btrfs_disk_key {
225 	__le64 objectid;
226 	u8 type;
227 	__le64 offset;
228 } __attribute__ ((__packed__));
229 
230 struct btrfs_key {
231 	u64 objectid;
232 	u8 type;
233 	u64 offset;
234 } __attribute__ ((__packed__));
235 
236 struct btrfs_mapping_tree {
237 	struct extent_map_tree map_tree;
238 };
239 
240 struct btrfs_dev_item {
241 	/* the internal btrfs device id */
242 	__le64 devid;
243 
244 	/* size of the device */
245 	__le64 total_bytes;
246 
247 	/* bytes used */
248 	__le64 bytes_used;
249 
250 	/* optimal io alignment for this device */
251 	__le32 io_align;
252 
253 	/* optimal io width for this device */
254 	__le32 io_width;
255 
256 	/* minimal io size for this device */
257 	__le32 sector_size;
258 
259 	/* type and info about this device */
260 	__le64 type;
261 
262 	/* expected generation for this device */
263 	__le64 generation;
264 
265 	/*
266 	 * starting byte of this partition on the device,
267 	 * to allow for stripe alignment in the future
268 	 */
269 	__le64 start_offset;
270 
271 	/* grouping information for allocation decisions */
272 	__le32 dev_group;
273 
274 	/* seek speed 0-100 where 100 is fastest */
275 	u8 seek_speed;
276 
277 	/* bandwidth 0-100 where 100 is fastest */
278 	u8 bandwidth;
279 
280 	/* btrfs generated uuid for this device */
281 	u8 uuid[BTRFS_UUID_SIZE];
282 
283 	/* uuid of FS who owns this device */
284 	u8 fsid[BTRFS_UUID_SIZE];
285 } __attribute__ ((__packed__));
286 
287 struct btrfs_stripe {
288 	__le64 devid;
289 	__le64 offset;
290 	u8 dev_uuid[BTRFS_UUID_SIZE];
291 } __attribute__ ((__packed__));
292 
293 struct btrfs_chunk {
294 	/* size of this chunk in bytes */
295 	__le64 length;
296 
297 	/* objectid of the root referencing this chunk */
298 	__le64 owner;
299 
300 	__le64 stripe_len;
301 	__le64 type;
302 
303 	/* optimal io alignment for this chunk */
304 	__le32 io_align;
305 
306 	/* optimal io width for this chunk */
307 	__le32 io_width;
308 
309 	/* minimal io size for this chunk */
310 	__le32 sector_size;
311 
312 	/* 2^16 stripes is quite a lot, a second limit is the size of a single
313 	 * item in the btree
314 	 */
315 	__le16 num_stripes;
316 
317 	/* sub stripes only matter for raid10 */
318 	__le16 sub_stripes;
319 	struct btrfs_stripe stripe;
320 	/* additional stripes go here */
321 } __attribute__ ((__packed__));
322 
323 #define BTRFS_FREE_SPACE_EXTENT	1
324 #define BTRFS_FREE_SPACE_BITMAP	2
325 
326 struct btrfs_free_space_entry {
327 	__le64 offset;
328 	__le64 bytes;
329 	u8 type;
330 } __attribute__ ((__packed__));
331 
332 struct btrfs_free_space_header {
333 	struct btrfs_disk_key location;
334 	__le64 generation;
335 	__le64 num_entries;
336 	__le64 num_bitmaps;
337 } __attribute__ ((__packed__));
338 
339 static inline unsigned long btrfs_chunk_item_size(int num_stripes)
340 {
341 	BUG_ON(num_stripes == 0);
342 	return sizeof(struct btrfs_chunk) +
343 		sizeof(struct btrfs_stripe) * (num_stripes - 1);
344 }
345 
346 #define BTRFS_HEADER_FLAG_WRITTEN	(1ULL << 0)
347 #define BTRFS_HEADER_FLAG_RELOC		(1ULL << 1)
348 
349 /*
350  * File system states
351  */
352 #define BTRFS_FS_STATE_ERROR		0
353 #define BTRFS_FS_STATE_REMOUNTING	1
354 #define BTRFS_FS_STATE_TRANS_ABORTED	2
355 #define BTRFS_FS_STATE_DEV_REPLACING	3
356 
357 /* Super block flags */
358 /* Errors detected */
359 #define BTRFS_SUPER_FLAG_ERROR		(1ULL << 2)
360 
361 #define BTRFS_SUPER_FLAG_SEEDING	(1ULL << 32)
362 #define BTRFS_SUPER_FLAG_METADUMP	(1ULL << 33)
363 
364 #define BTRFS_BACKREF_REV_MAX		256
365 #define BTRFS_BACKREF_REV_SHIFT		56
366 #define BTRFS_BACKREF_REV_MASK		(((u64)BTRFS_BACKREF_REV_MAX - 1) << \
367 					 BTRFS_BACKREF_REV_SHIFT)
368 
369 #define BTRFS_OLD_BACKREF_REV		0
370 #define BTRFS_MIXED_BACKREF_REV		1
371 
372 /*
373  * every tree block (leaf or node) starts with this header.
374  */
375 struct btrfs_header {
376 	/* these first four must match the super block */
377 	u8 csum[BTRFS_CSUM_SIZE];
378 	u8 fsid[BTRFS_FSID_SIZE]; /* FS specific uuid */
379 	__le64 bytenr; /* which block this node is supposed to live in */
380 	__le64 flags;
381 
382 	/* allowed to be different from the super from here on down */
383 	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
384 	__le64 generation;
385 	__le64 owner;
386 	__le32 nritems;
387 	u8 level;
388 } __attribute__ ((__packed__));
389 
390 #define BTRFS_NODEPTRS_PER_BLOCK(r) (((r)->nodesize - \
391 				      sizeof(struct btrfs_header)) / \
392 				     sizeof(struct btrfs_key_ptr))
393 #define __BTRFS_LEAF_DATA_SIZE(bs) ((bs) - sizeof(struct btrfs_header))
394 #define BTRFS_LEAF_DATA_SIZE(r) (__BTRFS_LEAF_DATA_SIZE(r->leafsize))
395 #define BTRFS_MAX_INLINE_DATA_SIZE(r) (BTRFS_LEAF_DATA_SIZE(r) - \
396 					sizeof(struct btrfs_item) - \
397 					sizeof(struct btrfs_file_extent_item))
398 #define BTRFS_MAX_XATTR_SIZE(r)	(BTRFS_LEAF_DATA_SIZE(r) - \
399 				 sizeof(struct btrfs_item) -\
400 				 sizeof(struct btrfs_dir_item))
401 
402 
403 /*
404  * this is a very generous portion of the super block, giving us
405  * room to translate 14 chunks with 3 stripes each.
406  */
407 #define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048
408 #define BTRFS_LABEL_SIZE 256
409 
410 /*
411  * just in case we somehow lose the roots and are not able to mount,
412  * we store an array of the roots from previous transactions
413  * in the super.
414  */
415 #define BTRFS_NUM_BACKUP_ROOTS 4
416 struct btrfs_root_backup {
417 	__le64 tree_root;
418 	__le64 tree_root_gen;
419 
420 	__le64 chunk_root;
421 	__le64 chunk_root_gen;
422 
423 	__le64 extent_root;
424 	__le64 extent_root_gen;
425 
426 	__le64 fs_root;
427 	__le64 fs_root_gen;
428 
429 	__le64 dev_root;
430 	__le64 dev_root_gen;
431 
432 	__le64 csum_root;
433 	__le64 csum_root_gen;
434 
435 	__le64 total_bytes;
436 	__le64 bytes_used;
437 	__le64 num_devices;
438 	/* future */
439 	__le64 unused_64[4];
440 
441 	u8 tree_root_level;
442 	u8 chunk_root_level;
443 	u8 extent_root_level;
444 	u8 fs_root_level;
445 	u8 dev_root_level;
446 	u8 csum_root_level;
447 	/* future and to align */
448 	u8 unused_8[10];
449 } __attribute__ ((__packed__));
450 
451 /*
452  * the super block basically lists the main trees of the FS
453  * it currently lacks any block count etc etc
454  */
455 struct btrfs_super_block {
456 	u8 csum[BTRFS_CSUM_SIZE];
457 	/* the first 4 fields must match struct btrfs_header */
458 	u8 fsid[BTRFS_FSID_SIZE];    /* FS specific uuid */
459 	__le64 bytenr; /* this block number */
460 	__le64 flags;
461 
462 	/* allowed to be different from the btrfs_header from here own down */
463 	__le64 magic;
464 	__le64 generation;
465 	__le64 root;
466 	__le64 chunk_root;
467 	__le64 log_root;
468 
469 	/* this will help find the new super based on the log root */
470 	__le64 log_root_transid;
471 	__le64 total_bytes;
472 	__le64 bytes_used;
473 	__le64 root_dir_objectid;
474 	__le64 num_devices;
475 	__le32 sectorsize;
476 	__le32 nodesize;
477 	__le32 leafsize;
478 	__le32 stripesize;
479 	__le32 sys_chunk_array_size;
480 	__le64 chunk_root_generation;
481 	__le64 compat_flags;
482 	__le64 compat_ro_flags;
483 	__le64 incompat_flags;
484 	__le16 csum_type;
485 	u8 root_level;
486 	u8 chunk_root_level;
487 	u8 log_root_level;
488 	struct btrfs_dev_item dev_item;
489 
490 	char label[BTRFS_LABEL_SIZE];
491 
492 	__le64 cache_generation;
493 	__le64 uuid_tree_generation;
494 
495 	/* future expansion */
496 	__le64 reserved[30];
497 	u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE];
498 	struct btrfs_root_backup super_roots[BTRFS_NUM_BACKUP_ROOTS];
499 } __attribute__ ((__packed__));
500 
501 /*
502  * Compat flags that we support.  If any incompat flags are set other than the
503  * ones specified below then we will fail to mount
504  */
505 #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF	(1ULL << 0)
506 #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL	(1ULL << 1)
507 #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS	(1ULL << 2)
508 #define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO	(1ULL << 3)
509 /*
510  * some patches floated around with a second compression method
511  * lets save that incompat here for when they do get in
512  * Note we don't actually support it, we're just reserving the
513  * number
514  */
515 #define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZOv2	(1ULL << 4)
516 
517 /*
518  * older kernels tried to do bigger metadata blocks, but the
519  * code was pretty buggy.  Lets not let them try anymore.
520  */
521 #define BTRFS_FEATURE_INCOMPAT_BIG_METADATA	(1ULL << 5)
522 
523 #define BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF	(1ULL << 6)
524 #define BTRFS_FEATURE_INCOMPAT_RAID56		(1ULL << 7)
525 #define BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA	(1ULL << 8)
526 #define BTRFS_FEATURE_INCOMPAT_NO_HOLES		(1ULL << 9)
527 
528 #define BTRFS_FEATURE_COMPAT_SUPP		0ULL
529 #define BTRFS_FEATURE_COMPAT_SAFE_SET		0ULL
530 #define BTRFS_FEATURE_COMPAT_SAFE_CLEAR		0ULL
531 #define BTRFS_FEATURE_COMPAT_RO_SUPP		0ULL
532 #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET	0ULL
533 #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR	0ULL
534 
535 #define BTRFS_FEATURE_INCOMPAT_SUPP			\
536 	(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |		\
537 	 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |	\
538 	 BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |		\
539 	 BTRFS_FEATURE_INCOMPAT_BIG_METADATA |		\
540 	 BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO |		\
541 	 BTRFS_FEATURE_INCOMPAT_RAID56 |		\
542 	 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF |		\
543 	 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA |	\
544 	 BTRFS_FEATURE_INCOMPAT_NO_HOLES)
545 
546 #define BTRFS_FEATURE_INCOMPAT_SAFE_SET			\
547 	(BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF)
548 #define BTRFS_FEATURE_INCOMPAT_SAFE_CLEAR		0ULL
549 
550 /*
551  * A leaf is full of items. offset and size tell us where to find
552  * the item in the leaf (relative to the start of the data area)
553  */
554 struct btrfs_item {
555 	struct btrfs_disk_key key;
556 	__le32 offset;
557 	__le32 size;
558 } __attribute__ ((__packed__));
559 
560 /*
561  * leaves have an item area and a data area:
562  * [item0, item1....itemN] [free space] [dataN...data1, data0]
563  *
564  * The data is separate from the items to get the keys closer together
565  * during searches.
566  */
567 struct btrfs_leaf {
568 	struct btrfs_header header;
569 	struct btrfs_item items[];
570 } __attribute__ ((__packed__));
571 
572 /*
573  * all non-leaf blocks are nodes, they hold only keys and pointers to
574  * other blocks
575  */
576 struct btrfs_key_ptr {
577 	struct btrfs_disk_key key;
578 	__le64 blockptr;
579 	__le64 generation;
580 } __attribute__ ((__packed__));
581 
582 struct btrfs_node {
583 	struct btrfs_header header;
584 	struct btrfs_key_ptr ptrs[];
585 } __attribute__ ((__packed__));
586 
587 /*
588  * btrfs_paths remember the path taken from the root down to the leaf.
589  * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
590  * to any other levels that are present.
591  *
592  * The slots array records the index of the item or block pointer
593  * used while walking the tree.
594  */
595 struct btrfs_path {
596 	struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
597 	int slots[BTRFS_MAX_LEVEL];
598 	/* if there is real range locking, this locks field will change */
599 	int locks[BTRFS_MAX_LEVEL];
600 	int reada;
601 	/* keep some upper locks as we walk down */
602 	int lowest_level;
603 
604 	/*
605 	 * set by btrfs_split_item, tells search_slot to keep all locks
606 	 * and to force calls to keep space in the nodes
607 	 */
608 	unsigned int search_for_split:1;
609 	unsigned int keep_locks:1;
610 	unsigned int skip_locking:1;
611 	unsigned int leave_spinning:1;
612 	unsigned int search_commit_root:1;
613 	unsigned int need_commit_sem:1;
614 };
615 
616 /*
617  * items in the extent btree are used to record the objectid of the
618  * owner of the block and the number of references
619  */
620 
621 struct btrfs_extent_item {
622 	__le64 refs;
623 	__le64 generation;
624 	__le64 flags;
625 } __attribute__ ((__packed__));
626 
627 struct btrfs_extent_item_v0 {
628 	__le32 refs;
629 } __attribute__ ((__packed__));
630 
631 #define BTRFS_MAX_EXTENT_ITEM_SIZE(r) ((BTRFS_LEAF_DATA_SIZE(r) >> 4) - \
632 					sizeof(struct btrfs_item))
633 
634 #define BTRFS_EXTENT_FLAG_DATA		(1ULL << 0)
635 #define BTRFS_EXTENT_FLAG_TREE_BLOCK	(1ULL << 1)
636 
637 /* following flags only apply to tree blocks */
638 
639 /* use full backrefs for extent pointers in the block */
640 #define BTRFS_BLOCK_FLAG_FULL_BACKREF	(1ULL << 8)
641 
642 /*
643  * this flag is only used internally by scrub and may be changed at any time
644  * it is only declared here to avoid collisions
645  */
646 #define BTRFS_EXTENT_FLAG_SUPER		(1ULL << 48)
647 
648 struct btrfs_tree_block_info {
649 	struct btrfs_disk_key key;
650 	u8 level;
651 } __attribute__ ((__packed__));
652 
653 struct btrfs_extent_data_ref {
654 	__le64 root;
655 	__le64 objectid;
656 	__le64 offset;
657 	__le32 count;
658 } __attribute__ ((__packed__));
659 
660 struct btrfs_shared_data_ref {
661 	__le32 count;
662 } __attribute__ ((__packed__));
663 
664 struct btrfs_extent_inline_ref {
665 	u8 type;
666 	__le64 offset;
667 } __attribute__ ((__packed__));
668 
669 /* old style backrefs item */
670 struct btrfs_extent_ref_v0 {
671 	__le64 root;
672 	__le64 generation;
673 	__le64 objectid;
674 	__le32 count;
675 } __attribute__ ((__packed__));
676 
677 
678 /* dev extents record free space on individual devices.  The owner
679  * field points back to the chunk allocation mapping tree that allocated
680  * the extent.  The chunk tree uuid field is a way to double check the owner
681  */
682 struct btrfs_dev_extent {
683 	__le64 chunk_tree;
684 	__le64 chunk_objectid;
685 	__le64 chunk_offset;
686 	__le64 length;
687 	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
688 } __attribute__ ((__packed__));
689 
690 struct btrfs_inode_ref {
691 	__le64 index;
692 	__le16 name_len;
693 	/* name goes here */
694 } __attribute__ ((__packed__));
695 
696 struct btrfs_inode_extref {
697 	__le64 parent_objectid;
698 	__le64 index;
699 	__le16 name_len;
700 	__u8   name[0];
701 	/* name goes here */
702 } __attribute__ ((__packed__));
703 
704 struct btrfs_timespec {
705 	__le64 sec;
706 	__le32 nsec;
707 } __attribute__ ((__packed__));
708 
709 enum btrfs_compression_type {
710 	BTRFS_COMPRESS_NONE  = 0,
711 	BTRFS_COMPRESS_ZLIB  = 1,
712 	BTRFS_COMPRESS_LZO   = 2,
713 	BTRFS_COMPRESS_TYPES = 2,
714 	BTRFS_COMPRESS_LAST  = 3,
715 };
716 
717 struct btrfs_inode_item {
718 	/* nfs style generation number */
719 	__le64 generation;
720 	/* transid that last touched this inode */
721 	__le64 transid;
722 	__le64 size;
723 	__le64 nbytes;
724 	__le64 block_group;
725 	__le32 nlink;
726 	__le32 uid;
727 	__le32 gid;
728 	__le32 mode;
729 	__le64 rdev;
730 	__le64 flags;
731 
732 	/* modification sequence number for NFS */
733 	__le64 sequence;
734 
735 	/*
736 	 * a little future expansion, for more than this we can
737 	 * just grow the inode item and version it
738 	 */
739 	__le64 reserved[4];
740 	struct btrfs_timespec atime;
741 	struct btrfs_timespec ctime;
742 	struct btrfs_timespec mtime;
743 	struct btrfs_timespec otime;
744 } __attribute__ ((__packed__));
745 
746 struct btrfs_dir_log_item {
747 	__le64 end;
748 } __attribute__ ((__packed__));
749 
750 struct btrfs_dir_item {
751 	struct btrfs_disk_key location;
752 	__le64 transid;
753 	__le16 data_len;
754 	__le16 name_len;
755 	u8 type;
756 } __attribute__ ((__packed__));
757 
758 #define BTRFS_ROOT_SUBVOL_RDONLY	(1ULL << 0)
759 
760 /*
761  * Internal in-memory flag that a subvolume has been marked for deletion but
762  * still visible as a directory
763  */
764 #define BTRFS_ROOT_SUBVOL_DEAD		(1ULL << 48)
765 
766 struct btrfs_root_item {
767 	struct btrfs_inode_item inode;
768 	__le64 generation;
769 	__le64 root_dirid;
770 	__le64 bytenr;
771 	__le64 byte_limit;
772 	__le64 bytes_used;
773 	__le64 last_snapshot;
774 	__le64 flags;
775 	__le32 refs;
776 	struct btrfs_disk_key drop_progress;
777 	u8 drop_level;
778 	u8 level;
779 
780 	/*
781 	 * The following fields appear after subvol_uuids+subvol_times
782 	 * were introduced.
783 	 */
784 
785 	/*
786 	 * This generation number is used to test if the new fields are valid
787 	 * and up to date while reading the root item. Everytime the root item
788 	 * is written out, the "generation" field is copied into this field. If
789 	 * anyone ever mounted the fs with an older kernel, we will have
790 	 * mismatching generation values here and thus must invalidate the
791 	 * new fields. See btrfs_update_root and btrfs_find_last_root for
792 	 * details.
793 	 * the offset of generation_v2 is also used as the start for the memset
794 	 * when invalidating the fields.
795 	 */
796 	__le64 generation_v2;
797 	u8 uuid[BTRFS_UUID_SIZE];
798 	u8 parent_uuid[BTRFS_UUID_SIZE];
799 	u8 received_uuid[BTRFS_UUID_SIZE];
800 	__le64 ctransid; /* updated when an inode changes */
801 	__le64 otransid; /* trans when created */
802 	__le64 stransid; /* trans when sent. non-zero for received subvol */
803 	__le64 rtransid; /* trans when received. non-zero for received subvol */
804 	struct btrfs_timespec ctime;
805 	struct btrfs_timespec otime;
806 	struct btrfs_timespec stime;
807 	struct btrfs_timespec rtime;
808 	__le64 reserved[8]; /* for future */
809 } __attribute__ ((__packed__));
810 
811 /*
812  * this is used for both forward and backward root refs
813  */
814 struct btrfs_root_ref {
815 	__le64 dirid;
816 	__le64 sequence;
817 	__le16 name_len;
818 } __attribute__ ((__packed__));
819 
820 struct btrfs_disk_balance_args {
821 	/*
822 	 * profiles to operate on, single is denoted by
823 	 * BTRFS_AVAIL_ALLOC_BIT_SINGLE
824 	 */
825 	__le64 profiles;
826 
827 	/* usage filter */
828 	__le64 usage;
829 
830 	/* devid filter */
831 	__le64 devid;
832 
833 	/* devid subset filter [pstart..pend) */
834 	__le64 pstart;
835 	__le64 pend;
836 
837 	/* btrfs virtual address space subset filter [vstart..vend) */
838 	__le64 vstart;
839 	__le64 vend;
840 
841 	/*
842 	 * profile to convert to, single is denoted by
843 	 * BTRFS_AVAIL_ALLOC_BIT_SINGLE
844 	 */
845 	__le64 target;
846 
847 	/* BTRFS_BALANCE_ARGS_* */
848 	__le64 flags;
849 
850 	/* BTRFS_BALANCE_ARGS_LIMIT value */
851 	__le64 limit;
852 
853 	__le64 unused[7];
854 } __attribute__ ((__packed__));
855 
856 /*
857  * store balance parameters to disk so that balance can be properly
858  * resumed after crash or unmount
859  */
860 struct btrfs_balance_item {
861 	/* BTRFS_BALANCE_* */
862 	__le64 flags;
863 
864 	struct btrfs_disk_balance_args data;
865 	struct btrfs_disk_balance_args meta;
866 	struct btrfs_disk_balance_args sys;
867 
868 	__le64 unused[4];
869 } __attribute__ ((__packed__));
870 
871 #define BTRFS_FILE_EXTENT_INLINE 0
872 #define BTRFS_FILE_EXTENT_REG 1
873 #define BTRFS_FILE_EXTENT_PREALLOC 2
874 
875 struct btrfs_file_extent_item {
876 	/*
877 	 * transaction id that created this extent
878 	 */
879 	__le64 generation;
880 	/*
881 	 * max number of bytes to hold this extent in ram
882 	 * when we split a compressed extent we can't know how big
883 	 * each of the resulting pieces will be.  So, this is
884 	 * an upper limit on the size of the extent in ram instead of
885 	 * an exact limit.
886 	 */
887 	__le64 ram_bytes;
888 
889 	/*
890 	 * 32 bits for the various ways we might encode the data,
891 	 * including compression and encryption.  If any of these
892 	 * are set to something a given disk format doesn't understand
893 	 * it is treated like an incompat flag for reading and writing,
894 	 * but not for stat.
895 	 */
896 	u8 compression;
897 	u8 encryption;
898 	__le16 other_encoding; /* spare for later use */
899 
900 	/* are we inline data or a real extent? */
901 	u8 type;
902 
903 	/*
904 	 * disk space consumed by the extent, checksum blocks are included
905 	 * in these numbers
906 	 */
907 	__le64 disk_bytenr;
908 	__le64 disk_num_bytes;
909 	/*
910 	 * the logical offset in file blocks (no csums)
911 	 * this extent record is for.  This allows a file extent to point
912 	 * into the middle of an existing extent on disk, sharing it
913 	 * between two snapshots (useful if some bytes in the middle of the
914 	 * extent have changed
915 	 */
916 	__le64 offset;
917 	/*
918 	 * the logical number of file blocks (no csums included).  This
919 	 * always reflects the size uncompressed and without encoding.
920 	 */
921 	__le64 num_bytes;
922 
923 } __attribute__ ((__packed__));
924 
925 struct btrfs_csum_item {
926 	u8 csum;
927 } __attribute__ ((__packed__));
928 
929 struct btrfs_dev_stats_item {
930 	/*
931 	 * grow this item struct at the end for future enhancements and keep
932 	 * the existing values unchanged
933 	 */
934 	__le64 values[BTRFS_DEV_STAT_VALUES_MAX];
935 } __attribute__ ((__packed__));
936 
937 #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_ALWAYS	0
938 #define BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID	1
939 #define BTRFS_DEV_REPLACE_ITEM_STATE_NEVER_STARTED	0
940 #define BTRFS_DEV_REPLACE_ITEM_STATE_STARTED		1
941 #define BTRFS_DEV_REPLACE_ITEM_STATE_SUSPENDED		2
942 #define BTRFS_DEV_REPLACE_ITEM_STATE_FINISHED		3
943 #define BTRFS_DEV_REPLACE_ITEM_STATE_CANCELED		4
944 
945 struct btrfs_dev_replace {
946 	u64 replace_state;	/* see #define above */
947 	u64 time_started;	/* seconds since 1-Jan-1970 */
948 	u64 time_stopped;	/* seconds since 1-Jan-1970 */
949 	atomic64_t num_write_errors;
950 	atomic64_t num_uncorrectable_read_errors;
951 
952 	u64 cursor_left;
953 	u64 committed_cursor_left;
954 	u64 cursor_left_last_write_of_item;
955 	u64 cursor_right;
956 
957 	u64 cont_reading_from_srcdev_mode;	/* see #define above */
958 
959 	int is_valid;
960 	int item_needs_writeback;
961 	struct btrfs_device *srcdev;
962 	struct btrfs_device *tgtdev;
963 
964 	pid_t lock_owner;
965 	atomic_t nesting_level;
966 	struct mutex lock_finishing_cancel_unmount;
967 	struct mutex lock_management_lock;
968 	struct mutex lock;
969 
970 	struct btrfs_scrub_progress scrub_progress;
971 };
972 
973 struct btrfs_dev_replace_item {
974 	/*
975 	 * grow this item struct at the end for future enhancements and keep
976 	 * the existing values unchanged
977 	 */
978 	__le64 src_devid;
979 	__le64 cursor_left;
980 	__le64 cursor_right;
981 	__le64 cont_reading_from_srcdev_mode;
982 
983 	__le64 replace_state;
984 	__le64 time_started;
985 	__le64 time_stopped;
986 	__le64 num_write_errors;
987 	__le64 num_uncorrectable_read_errors;
988 } __attribute__ ((__packed__));
989 
990 /* different types of block groups (and chunks) */
991 #define BTRFS_BLOCK_GROUP_DATA		(1ULL << 0)
992 #define BTRFS_BLOCK_GROUP_SYSTEM	(1ULL << 1)
993 #define BTRFS_BLOCK_GROUP_METADATA	(1ULL << 2)
994 #define BTRFS_BLOCK_GROUP_RAID0		(1ULL << 3)
995 #define BTRFS_BLOCK_GROUP_RAID1		(1ULL << 4)
996 #define BTRFS_BLOCK_GROUP_DUP		(1ULL << 5)
997 #define BTRFS_BLOCK_GROUP_RAID10	(1ULL << 6)
998 #define BTRFS_BLOCK_GROUP_RAID5         (1ULL << 7)
999 #define BTRFS_BLOCK_GROUP_RAID6         (1ULL << 8)
1000 #define BTRFS_BLOCK_GROUP_RESERVED	(BTRFS_AVAIL_ALLOC_BIT_SINGLE | \
1001 					 BTRFS_SPACE_INFO_GLOBAL_RSV)
1002 
1003 enum btrfs_raid_types {
1004 	BTRFS_RAID_RAID10,
1005 	BTRFS_RAID_RAID1,
1006 	BTRFS_RAID_DUP,
1007 	BTRFS_RAID_RAID0,
1008 	BTRFS_RAID_SINGLE,
1009 	BTRFS_RAID_RAID5,
1010 	BTRFS_RAID_RAID6,
1011 	BTRFS_NR_RAID_TYPES
1012 };
1013 
1014 #define BTRFS_BLOCK_GROUP_TYPE_MASK	(BTRFS_BLOCK_GROUP_DATA |    \
1015 					 BTRFS_BLOCK_GROUP_SYSTEM |  \
1016 					 BTRFS_BLOCK_GROUP_METADATA)
1017 
1018 #define BTRFS_BLOCK_GROUP_PROFILE_MASK	(BTRFS_BLOCK_GROUP_RAID0 |   \
1019 					 BTRFS_BLOCK_GROUP_RAID1 |   \
1020 					 BTRFS_BLOCK_GROUP_RAID5 |   \
1021 					 BTRFS_BLOCK_GROUP_RAID6 |   \
1022 					 BTRFS_BLOCK_GROUP_DUP |     \
1023 					 BTRFS_BLOCK_GROUP_RAID10)
1024 /*
1025  * We need a bit for restriper to be able to tell when chunks of type
1026  * SINGLE are available.  This "extended" profile format is used in
1027  * fs_info->avail_*_alloc_bits (in-memory) and balance item fields
1028  * (on-disk).  The corresponding on-disk bit in chunk.type is reserved
1029  * to avoid remappings between two formats in future.
1030  */
1031 #define BTRFS_AVAIL_ALLOC_BIT_SINGLE	(1ULL << 48)
1032 
1033 /*
1034  * A fake block group type that is used to communicate global block reserve
1035  * size to userspace via the SPACE_INFO ioctl.
1036  */
1037 #define BTRFS_SPACE_INFO_GLOBAL_RSV	(1ULL << 49)
1038 
1039 #define BTRFS_EXTENDED_PROFILE_MASK	(BTRFS_BLOCK_GROUP_PROFILE_MASK | \
1040 					 BTRFS_AVAIL_ALLOC_BIT_SINGLE)
1041 
1042 static inline u64 chunk_to_extended(u64 flags)
1043 {
1044 	if ((flags & BTRFS_BLOCK_GROUP_PROFILE_MASK) == 0)
1045 		flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE;
1046 
1047 	return flags;
1048 }
1049 static inline u64 extended_to_chunk(u64 flags)
1050 {
1051 	return flags & ~BTRFS_AVAIL_ALLOC_BIT_SINGLE;
1052 }
1053 
1054 struct btrfs_block_group_item {
1055 	__le64 used;
1056 	__le64 chunk_objectid;
1057 	__le64 flags;
1058 } __attribute__ ((__packed__));
1059 
1060 /*
1061  * is subvolume quota turned on?
1062  */
1063 #define BTRFS_QGROUP_STATUS_FLAG_ON		(1ULL << 0)
1064 /*
1065  * RESCAN is set during the initialization phase
1066  */
1067 #define BTRFS_QGROUP_STATUS_FLAG_RESCAN		(1ULL << 1)
1068 /*
1069  * Some qgroup entries are known to be out of date,
1070  * either because the configuration has changed in a way that
1071  * makes a rescan necessary, or because the fs has been mounted
1072  * with a non-qgroup-aware version.
1073  * Turning qouta off and on again makes it inconsistent, too.
1074  */
1075 #define BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT	(1ULL << 2)
1076 
1077 #define BTRFS_QGROUP_STATUS_VERSION        1
1078 
1079 struct btrfs_qgroup_status_item {
1080 	__le64 version;
1081 	/*
1082 	 * the generation is updated during every commit. As older
1083 	 * versions of btrfs are not aware of qgroups, it will be
1084 	 * possible to detect inconsistencies by checking the
1085 	 * generation on mount time
1086 	 */
1087 	__le64 generation;
1088 
1089 	/* flag definitions see above */
1090 	__le64 flags;
1091 
1092 	/*
1093 	 * only used during scanning to record the progress
1094 	 * of the scan. It contains a logical address
1095 	 */
1096 	__le64 rescan;
1097 } __attribute__ ((__packed__));
1098 
1099 struct btrfs_qgroup_info_item {
1100 	__le64 generation;
1101 	__le64 rfer;
1102 	__le64 rfer_cmpr;
1103 	__le64 excl;
1104 	__le64 excl_cmpr;
1105 } __attribute__ ((__packed__));
1106 
1107 /* flags definition for qgroup limits */
1108 #define BTRFS_QGROUP_LIMIT_MAX_RFER	(1ULL << 0)
1109 #define BTRFS_QGROUP_LIMIT_MAX_EXCL	(1ULL << 1)
1110 #define BTRFS_QGROUP_LIMIT_RSV_RFER	(1ULL << 2)
1111 #define BTRFS_QGROUP_LIMIT_RSV_EXCL	(1ULL << 3)
1112 #define BTRFS_QGROUP_LIMIT_RFER_CMPR	(1ULL << 4)
1113 #define BTRFS_QGROUP_LIMIT_EXCL_CMPR	(1ULL << 5)
1114 
1115 struct btrfs_qgroup_limit_item {
1116 	/*
1117 	 * only updated when any of the other values change
1118 	 */
1119 	__le64 flags;
1120 	__le64 max_rfer;
1121 	__le64 max_excl;
1122 	__le64 rsv_rfer;
1123 	__le64 rsv_excl;
1124 } __attribute__ ((__packed__));
1125 
1126 /* For raid type sysfs entries */
1127 struct raid_kobject {
1128 	int raid_type;
1129 	struct kobject kobj;
1130 };
1131 
1132 struct btrfs_space_info {
1133 	spinlock_t lock;
1134 
1135 	u64 total_bytes;	/* total bytes in the space,
1136 				   this doesn't take mirrors into account */
1137 	u64 bytes_used;		/* total bytes used,
1138 				   this doesn't take mirrors into account */
1139 	u64 bytes_pinned;	/* total bytes pinned, will be freed when the
1140 				   transaction finishes */
1141 	u64 bytes_reserved;	/* total bytes the allocator has reserved for
1142 				   current allocations */
1143 	u64 bytes_may_use;	/* number of bytes that may be used for
1144 				   delalloc/allocations */
1145 	u64 bytes_readonly;	/* total bytes that are read only */
1146 
1147 	unsigned int full:1;	/* indicates that we cannot allocate any more
1148 				   chunks for this space */
1149 	unsigned int chunk_alloc:1;	/* set if we are allocating a chunk */
1150 
1151 	unsigned int flush:1;		/* set if we are trying to make space */
1152 
1153 	unsigned int force_alloc;	/* set if we need to force a chunk
1154 					   alloc for this space */
1155 
1156 	u64 disk_used;		/* total bytes used on disk */
1157 	u64 disk_total;		/* total bytes on disk, takes mirrors into
1158 				   account */
1159 
1160 	u64 flags;
1161 
1162 	/*
1163 	 * bytes_pinned is kept in line with what is actually pinned, as in
1164 	 * we've called update_block_group and dropped the bytes_used counter
1165 	 * and increased the bytes_pinned counter.  However this means that
1166 	 * bytes_pinned does not reflect the bytes that will be pinned once the
1167 	 * delayed refs are flushed, so this counter is inc'ed everytime we call
1168 	 * btrfs_free_extent so it is a realtime count of what will be freed
1169 	 * once the transaction is committed.  It will be zero'ed everytime the
1170 	 * transaction commits.
1171 	 */
1172 	struct percpu_counter total_bytes_pinned;
1173 
1174 	struct list_head list;
1175 
1176 	struct rw_semaphore groups_sem;
1177 	/* for block groups in our same type */
1178 	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
1179 	wait_queue_head_t wait;
1180 
1181 	struct kobject kobj;
1182 	struct kobject *block_group_kobjs[BTRFS_NR_RAID_TYPES];
1183 };
1184 
1185 #define	BTRFS_BLOCK_RSV_GLOBAL		1
1186 #define	BTRFS_BLOCK_RSV_DELALLOC	2
1187 #define	BTRFS_BLOCK_RSV_TRANS		3
1188 #define	BTRFS_BLOCK_RSV_CHUNK		4
1189 #define	BTRFS_BLOCK_RSV_DELOPS		5
1190 #define	BTRFS_BLOCK_RSV_EMPTY		6
1191 #define	BTRFS_BLOCK_RSV_TEMP		7
1192 
1193 struct btrfs_block_rsv {
1194 	u64 size;
1195 	u64 reserved;
1196 	struct btrfs_space_info *space_info;
1197 	spinlock_t lock;
1198 	unsigned short full;
1199 	unsigned short type;
1200 	unsigned short failfast;
1201 };
1202 
1203 /*
1204  * free clusters are used to claim free space in relatively large chunks,
1205  * allowing us to do less seeky writes.  They are used for all metadata
1206  * allocations and data allocations in ssd mode.
1207  */
1208 struct btrfs_free_cluster {
1209 	spinlock_t lock;
1210 	spinlock_t refill_lock;
1211 	struct rb_root root;
1212 
1213 	/* largest extent in this cluster */
1214 	u64 max_size;
1215 
1216 	/* first extent starting offset */
1217 	u64 window_start;
1218 
1219 	struct btrfs_block_group_cache *block_group;
1220 	/*
1221 	 * when a cluster is allocated from a block group, we put the
1222 	 * cluster onto a list in the block group so that it can
1223 	 * be freed before the block group is freed.
1224 	 */
1225 	struct list_head block_group_list;
1226 };
1227 
1228 enum btrfs_caching_type {
1229 	BTRFS_CACHE_NO		= 0,
1230 	BTRFS_CACHE_STARTED	= 1,
1231 	BTRFS_CACHE_FAST	= 2,
1232 	BTRFS_CACHE_FINISHED	= 3,
1233 	BTRFS_CACHE_ERROR	= 4,
1234 };
1235 
1236 enum btrfs_disk_cache_state {
1237 	BTRFS_DC_WRITTEN	= 0,
1238 	BTRFS_DC_ERROR		= 1,
1239 	BTRFS_DC_CLEAR		= 2,
1240 	BTRFS_DC_SETUP		= 3,
1241 	BTRFS_DC_NEED_WRITE	= 4,
1242 };
1243 
1244 struct btrfs_caching_control {
1245 	struct list_head list;
1246 	struct mutex mutex;
1247 	wait_queue_head_t wait;
1248 	struct btrfs_work work;
1249 	struct btrfs_block_group_cache *block_group;
1250 	u64 progress;
1251 	atomic_t count;
1252 };
1253 
1254 struct btrfs_block_group_cache {
1255 	struct btrfs_key key;
1256 	struct btrfs_block_group_item item;
1257 	struct btrfs_fs_info *fs_info;
1258 	struct inode *inode;
1259 	spinlock_t lock;
1260 	u64 pinned;
1261 	u64 reserved;
1262 	u64 delalloc_bytes;
1263 	u64 bytes_super;
1264 	u64 flags;
1265 	u64 sectorsize;
1266 	u64 cache_generation;
1267 
1268 	/*
1269 	 * It is just used for the delayed data space allocation because
1270 	 * only the data space allocation and the relative metadata update
1271 	 * can be done cross the transaction.
1272 	 */
1273 	struct rw_semaphore data_rwsem;
1274 
1275 	/* for raid56, this is a full stripe, without parity */
1276 	unsigned long full_stripe_len;
1277 
1278 	unsigned int ro:1;
1279 	unsigned int dirty:1;
1280 	unsigned int iref:1;
1281 
1282 	int disk_cache_state;
1283 
1284 	/* cache tracking stuff */
1285 	int cached;
1286 	struct btrfs_caching_control *caching_ctl;
1287 	u64 last_byte_to_unpin;
1288 
1289 	struct btrfs_space_info *space_info;
1290 
1291 	/* free space cache stuff */
1292 	struct btrfs_free_space_ctl *free_space_ctl;
1293 
1294 	/* block group cache stuff */
1295 	struct rb_node cache_node;
1296 
1297 	/* for block groups in the same raid type */
1298 	struct list_head list;
1299 
1300 	/* usage count */
1301 	atomic_t count;
1302 
1303 	/* List of struct btrfs_free_clusters for this block group.
1304 	 * Today it will only have one thing on it, but that may change
1305 	 */
1306 	struct list_head cluster_list;
1307 
1308 	/* For delayed block group creation */
1309 	struct list_head new_bg_list;
1310 };
1311 
1312 /* delayed seq elem */
1313 struct seq_list {
1314 	struct list_head list;
1315 	u64 seq;
1316 };
1317 
1318 enum btrfs_orphan_cleanup_state {
1319 	ORPHAN_CLEANUP_STARTED	= 1,
1320 	ORPHAN_CLEANUP_DONE	= 2,
1321 };
1322 
1323 /* used by the raid56 code to lock stripes for read/modify/write */
1324 struct btrfs_stripe_hash {
1325 	struct list_head hash_list;
1326 	wait_queue_head_t wait;
1327 	spinlock_t lock;
1328 };
1329 
1330 /* used by the raid56 code to lock stripes for read/modify/write */
1331 struct btrfs_stripe_hash_table {
1332 	struct list_head stripe_cache;
1333 	spinlock_t cache_lock;
1334 	int cache_size;
1335 	struct btrfs_stripe_hash table[];
1336 };
1337 
1338 #define BTRFS_STRIPE_HASH_TABLE_BITS 11
1339 
1340 void btrfs_init_async_reclaim_work(struct work_struct *work);
1341 
1342 /* fs_info */
1343 struct reloc_control;
1344 struct btrfs_device;
1345 struct btrfs_fs_devices;
1346 struct btrfs_balance_control;
1347 struct btrfs_delayed_root;
1348 struct btrfs_fs_info {
1349 	u8 fsid[BTRFS_FSID_SIZE];
1350 	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
1351 	struct btrfs_root *extent_root;
1352 	struct btrfs_root *tree_root;
1353 	struct btrfs_root *chunk_root;
1354 	struct btrfs_root *dev_root;
1355 	struct btrfs_root *fs_root;
1356 	struct btrfs_root *csum_root;
1357 	struct btrfs_root *quota_root;
1358 	struct btrfs_root *uuid_root;
1359 
1360 	/* the log root tree is a directory of all the other log roots */
1361 	struct btrfs_root *log_root_tree;
1362 
1363 	spinlock_t fs_roots_radix_lock;
1364 	struct radix_tree_root fs_roots_radix;
1365 
1366 	/* block group cache stuff */
1367 	spinlock_t block_group_cache_lock;
1368 	u64 first_logical_byte;
1369 	struct rb_root block_group_cache_tree;
1370 
1371 	/* keep track of unallocated space */
1372 	spinlock_t free_chunk_lock;
1373 	u64 free_chunk_space;
1374 
1375 	struct extent_io_tree freed_extents[2];
1376 	struct extent_io_tree *pinned_extents;
1377 
1378 	/* logical->physical extent mapping */
1379 	struct btrfs_mapping_tree mapping_tree;
1380 
1381 	/*
1382 	 * block reservation for extent, checksum, root tree and
1383 	 * delayed dir index item
1384 	 */
1385 	struct btrfs_block_rsv global_block_rsv;
1386 	/* block reservation for delay allocation */
1387 	struct btrfs_block_rsv delalloc_block_rsv;
1388 	/* block reservation for metadata operations */
1389 	struct btrfs_block_rsv trans_block_rsv;
1390 	/* block reservation for chunk tree */
1391 	struct btrfs_block_rsv chunk_block_rsv;
1392 	/* block reservation for delayed operations */
1393 	struct btrfs_block_rsv delayed_block_rsv;
1394 
1395 	struct btrfs_block_rsv empty_block_rsv;
1396 
1397 	u64 generation;
1398 	u64 last_trans_committed;
1399 	u64 avg_delayed_ref_runtime;
1400 
1401 	/*
1402 	 * this is updated to the current trans every time a full commit
1403 	 * is required instead of the faster short fsync log commits
1404 	 */
1405 	u64 last_trans_log_full_commit;
1406 	unsigned long mount_opt;
1407 	unsigned long compress_type:4;
1408 	int commit_interval;
1409 	/*
1410 	 * It is a suggestive number, the read side is safe even it gets a
1411 	 * wrong number because we will write out the data into a regular
1412 	 * extent. The write side(mount/remount) is under ->s_umount lock,
1413 	 * so it is also safe.
1414 	 */
1415 	u64 max_inline;
1416 	/*
1417 	 * Protected by ->chunk_mutex and sb->s_umount.
1418 	 *
1419 	 * The reason that we use two lock to protect it is because only
1420 	 * remount and mount operations can change it and these two operations
1421 	 * are under sb->s_umount, but the read side (chunk allocation) can not
1422 	 * acquire sb->s_umount or the deadlock would happen. So we use two
1423 	 * locks to protect it. On the write side, we must acquire two locks,
1424 	 * and on the read side, we just need acquire one of them.
1425 	 */
1426 	u64 alloc_start;
1427 	struct btrfs_transaction *running_transaction;
1428 	wait_queue_head_t transaction_throttle;
1429 	wait_queue_head_t transaction_wait;
1430 	wait_queue_head_t transaction_blocked_wait;
1431 	wait_queue_head_t async_submit_wait;
1432 
1433 	/*
1434 	 * Used to protect the incompat_flags, compat_flags, compat_ro_flags
1435 	 * when they are updated.
1436 	 *
1437 	 * Because we do not clear the flags for ever, so we needn't use
1438 	 * the lock on the read side.
1439 	 *
1440 	 * We also needn't use the lock when we mount the fs, because
1441 	 * there is no other task which will update the flag.
1442 	 */
1443 	spinlock_t super_lock;
1444 	struct btrfs_super_block *super_copy;
1445 	struct btrfs_super_block *super_for_commit;
1446 	struct block_device *__bdev;
1447 	struct super_block *sb;
1448 	struct inode *btree_inode;
1449 	struct backing_dev_info bdi;
1450 	struct mutex tree_log_mutex;
1451 	struct mutex transaction_kthread_mutex;
1452 	struct mutex cleaner_mutex;
1453 	struct mutex chunk_mutex;
1454 	struct mutex volume_mutex;
1455 
1456 	/* this is used during read/modify/write to make sure
1457 	 * no two ios are trying to mod the same stripe at the same
1458 	 * time
1459 	 */
1460 	struct btrfs_stripe_hash_table *stripe_hash_table;
1461 
1462 	/*
1463 	 * this protects the ordered operations list only while we are
1464 	 * processing all of the entries on it.  This way we make
1465 	 * sure the commit code doesn't find the list temporarily empty
1466 	 * because another function happens to be doing non-waiting preflush
1467 	 * before jumping into the main commit.
1468 	 */
1469 	struct mutex ordered_operations_mutex;
1470 
1471 	/*
1472 	 * Same as ordered_operations_mutex except this is for ordered extents
1473 	 * and not the operations.
1474 	 */
1475 	struct mutex ordered_extent_flush_mutex;
1476 
1477 	struct rw_semaphore commit_root_sem;
1478 
1479 	struct rw_semaphore cleanup_work_sem;
1480 
1481 	struct rw_semaphore subvol_sem;
1482 	struct srcu_struct subvol_srcu;
1483 
1484 	spinlock_t trans_lock;
1485 	/*
1486 	 * the reloc mutex goes with the trans lock, it is taken
1487 	 * during commit to protect us from the relocation code
1488 	 */
1489 	struct mutex reloc_mutex;
1490 
1491 	struct list_head trans_list;
1492 	struct list_head dead_roots;
1493 	struct list_head caching_block_groups;
1494 
1495 	spinlock_t delayed_iput_lock;
1496 	struct list_head delayed_iputs;
1497 
1498 	/* this protects tree_mod_seq_list */
1499 	spinlock_t tree_mod_seq_lock;
1500 	atomic64_t tree_mod_seq;
1501 	struct list_head tree_mod_seq_list;
1502 
1503 	/* this protects tree_mod_log */
1504 	rwlock_t tree_mod_log_lock;
1505 	struct rb_root tree_mod_log;
1506 
1507 	atomic_t nr_async_submits;
1508 	atomic_t async_submit_draining;
1509 	atomic_t nr_async_bios;
1510 	atomic_t async_delalloc_pages;
1511 	atomic_t open_ioctl_trans;
1512 
1513 	/*
1514 	 * this is used to protect the following list -- ordered_roots.
1515 	 */
1516 	spinlock_t ordered_root_lock;
1517 
1518 	/*
1519 	 * all fs/file tree roots in which there are data=ordered extents
1520 	 * pending writeback are added into this list.
1521 	 *
1522 	 * these can span multiple transactions and basically include
1523 	 * every dirty data page that isn't from nodatacow
1524 	 */
1525 	struct list_head ordered_roots;
1526 
1527 	struct mutex delalloc_root_mutex;
1528 	spinlock_t delalloc_root_lock;
1529 	/* all fs/file tree roots that have delalloc inodes. */
1530 	struct list_head delalloc_roots;
1531 
1532 	/*
1533 	 * there is a pool of worker threads for checksumming during writes
1534 	 * and a pool for checksumming after reads.  This is because readers
1535 	 * can run with FS locks held, and the writers may be waiting for
1536 	 * those locks.  We don't want ordering in the pending list to cause
1537 	 * deadlocks, and so the two are serviced separately.
1538 	 *
1539 	 * A third pool does submit_bio to avoid deadlocking with the other
1540 	 * two
1541 	 */
1542 	struct btrfs_workqueue *workers;
1543 	struct btrfs_workqueue *delalloc_workers;
1544 	struct btrfs_workqueue *flush_workers;
1545 	struct btrfs_workqueue *endio_workers;
1546 	struct btrfs_workqueue *endio_meta_workers;
1547 	struct btrfs_workqueue *endio_raid56_workers;
1548 	struct btrfs_workqueue *rmw_workers;
1549 	struct btrfs_workqueue *endio_meta_write_workers;
1550 	struct btrfs_workqueue *endio_write_workers;
1551 	struct btrfs_workqueue *endio_freespace_worker;
1552 	struct btrfs_workqueue *submit_workers;
1553 	struct btrfs_workqueue *caching_workers;
1554 	struct btrfs_workqueue *readahead_workers;
1555 
1556 	/*
1557 	 * fixup workers take dirty pages that didn't properly go through
1558 	 * the cow mechanism and make them safe to write.  It happens
1559 	 * for the sys_munmap function call path
1560 	 */
1561 	struct btrfs_workqueue *fixup_workers;
1562 	struct btrfs_workqueue *delayed_workers;
1563 
1564 	/* the extent workers do delayed refs on the extent allocation tree */
1565 	struct btrfs_workqueue *extent_workers;
1566 	struct task_struct *transaction_kthread;
1567 	struct task_struct *cleaner_kthread;
1568 	int thread_pool_size;
1569 
1570 	struct kobject super_kobj;
1571 	struct kobject *space_info_kobj;
1572 	struct kobject *device_dir_kobj;
1573 	struct completion kobj_unregister;
1574 	int do_barriers;
1575 	int closing;
1576 	int log_root_recovering;
1577 
1578 	u64 total_pinned;
1579 
1580 	/* used to keep from writing metadata until there is a nice batch */
1581 	struct percpu_counter dirty_metadata_bytes;
1582 	struct percpu_counter delalloc_bytes;
1583 	s32 dirty_metadata_batch;
1584 	s32 delalloc_batch;
1585 
1586 	struct list_head dirty_cowonly_roots;
1587 
1588 	struct btrfs_fs_devices *fs_devices;
1589 
1590 	/*
1591 	 * the space_info list is almost entirely read only.  It only changes
1592 	 * when we add a new raid type to the FS, and that happens
1593 	 * very rarely.  RCU is used to protect it.
1594 	 */
1595 	struct list_head space_info;
1596 
1597 	struct btrfs_space_info *data_sinfo;
1598 
1599 	struct reloc_control *reloc_ctl;
1600 
1601 	/* data_alloc_cluster is only used in ssd mode */
1602 	struct btrfs_free_cluster data_alloc_cluster;
1603 
1604 	/* all metadata allocations go through this cluster */
1605 	struct btrfs_free_cluster meta_alloc_cluster;
1606 
1607 	/* auto defrag inodes go here */
1608 	spinlock_t defrag_inodes_lock;
1609 	struct rb_root defrag_inodes;
1610 	atomic_t defrag_running;
1611 
1612 	/* Used to protect avail_{data, metadata, system}_alloc_bits */
1613 	seqlock_t profiles_lock;
1614 	/*
1615 	 * these three are in extended format (availability of single
1616 	 * chunks is denoted by BTRFS_AVAIL_ALLOC_BIT_SINGLE bit, other
1617 	 * types are denoted by corresponding BTRFS_BLOCK_GROUP_* bits)
1618 	 */
1619 	u64 avail_data_alloc_bits;
1620 	u64 avail_metadata_alloc_bits;
1621 	u64 avail_system_alloc_bits;
1622 
1623 	/* restriper state */
1624 	spinlock_t balance_lock;
1625 	struct mutex balance_mutex;
1626 	atomic_t balance_running;
1627 	atomic_t balance_pause_req;
1628 	atomic_t balance_cancel_req;
1629 	struct btrfs_balance_control *balance_ctl;
1630 	wait_queue_head_t balance_wait_q;
1631 
1632 	unsigned data_chunk_allocations;
1633 	unsigned metadata_ratio;
1634 
1635 	void *bdev_holder;
1636 
1637 	/* private scrub information */
1638 	struct mutex scrub_lock;
1639 	atomic_t scrubs_running;
1640 	atomic_t scrub_pause_req;
1641 	atomic_t scrubs_paused;
1642 	atomic_t scrub_cancel_req;
1643 	wait_queue_head_t scrub_pause_wait;
1644 	int scrub_workers_refcnt;
1645 	struct btrfs_workqueue *scrub_workers;
1646 	struct btrfs_workqueue *scrub_wr_completion_workers;
1647 	struct btrfs_workqueue *scrub_nocow_workers;
1648 
1649 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
1650 	u32 check_integrity_print_mask;
1651 #endif
1652 	/*
1653 	 * quota information
1654 	 */
1655 	unsigned int quota_enabled:1;
1656 
1657 	/*
1658 	 * quota_enabled only changes state after a commit. This holds the
1659 	 * next state.
1660 	 */
1661 	unsigned int pending_quota_state:1;
1662 
1663 	/* is qgroup tracking in a consistent state? */
1664 	u64 qgroup_flags;
1665 
1666 	/* holds configuration and tracking. Protected by qgroup_lock */
1667 	struct rb_root qgroup_tree;
1668 	struct rb_root qgroup_op_tree;
1669 	spinlock_t qgroup_lock;
1670 	spinlock_t qgroup_op_lock;
1671 	atomic_t qgroup_op_seq;
1672 
1673 	/*
1674 	 * used to avoid frequently calling ulist_alloc()/ulist_free()
1675 	 * when doing qgroup accounting, it must be protected by qgroup_lock.
1676 	 */
1677 	struct ulist *qgroup_ulist;
1678 
1679 	/* protect user change for quota operations */
1680 	struct mutex qgroup_ioctl_lock;
1681 
1682 	/* list of dirty qgroups to be written at next commit */
1683 	struct list_head dirty_qgroups;
1684 
1685 	/* used by btrfs_qgroup_record_ref for an efficient tree traversal */
1686 	u64 qgroup_seq;
1687 
1688 	/* qgroup rescan items */
1689 	struct mutex qgroup_rescan_lock; /* protects the progress item */
1690 	struct btrfs_key qgroup_rescan_progress;
1691 	struct btrfs_workqueue *qgroup_rescan_workers;
1692 	struct completion qgroup_rescan_completion;
1693 	struct btrfs_work qgroup_rescan_work;
1694 
1695 	/* filesystem state */
1696 	unsigned long fs_state;
1697 
1698 	struct btrfs_delayed_root *delayed_root;
1699 
1700 	/* readahead tree */
1701 	spinlock_t reada_lock;
1702 	struct radix_tree_root reada_tree;
1703 
1704 	/* Extent buffer radix tree */
1705 	spinlock_t buffer_lock;
1706 	struct radix_tree_root buffer_radix;
1707 
1708 	/* next backup root to be overwritten */
1709 	int backup_root_index;
1710 
1711 	int num_tolerated_disk_barrier_failures;
1712 
1713 	/* device replace state */
1714 	struct btrfs_dev_replace dev_replace;
1715 
1716 	atomic_t mutually_exclusive_operation_running;
1717 
1718 	struct percpu_counter bio_counter;
1719 	wait_queue_head_t replace_wait;
1720 
1721 	struct semaphore uuid_tree_rescan_sem;
1722 	unsigned int update_uuid_tree_gen:1;
1723 
1724 	/* Used to reclaim the metadata space in the background. */
1725 	struct work_struct async_reclaim_work;
1726 };
1727 
1728 struct btrfs_subvolume_writers {
1729 	struct percpu_counter	counter;
1730 	wait_queue_head_t	wait;
1731 };
1732 
1733 /*
1734  * The state of btrfs root
1735  */
1736 /*
1737  * btrfs_record_root_in_trans is a multi-step process,
1738  * and it can race with the balancing code.   But the
1739  * race is very small, and only the first time the root
1740  * is added to each transaction.  So IN_TRANS_SETUP
1741  * is used to tell us when more checks are required
1742  */
1743 #define BTRFS_ROOT_IN_TRANS_SETUP	0
1744 #define BTRFS_ROOT_REF_COWS		1
1745 #define BTRFS_ROOT_TRACK_DIRTY		2
1746 #define BTRFS_ROOT_IN_RADIX		3
1747 #define BTRFS_ROOT_DUMMY_ROOT		4
1748 #define BTRFS_ROOT_ORPHAN_ITEM_INSERTED	5
1749 #define BTRFS_ROOT_DEFRAG_RUNNING	6
1750 #define BTRFS_ROOT_FORCE_COW		7
1751 #define BTRFS_ROOT_MULTI_LOG_TASKS	8
1752 
1753 /*
1754  * in ram representation of the tree.  extent_root is used for all allocations
1755  * and for the extent tree extent_root root.
1756  */
1757 struct btrfs_root {
1758 	struct extent_buffer *node;
1759 
1760 	struct extent_buffer *commit_root;
1761 	struct btrfs_root *log_root;
1762 	struct btrfs_root *reloc_root;
1763 
1764 	unsigned long state;
1765 	struct btrfs_root_item root_item;
1766 	struct btrfs_key root_key;
1767 	struct btrfs_fs_info *fs_info;
1768 	struct extent_io_tree dirty_log_pages;
1769 
1770 	struct kobject root_kobj;
1771 	struct completion kobj_unregister;
1772 	struct mutex objectid_mutex;
1773 
1774 	spinlock_t accounting_lock;
1775 	struct btrfs_block_rsv *block_rsv;
1776 
1777 	/* free ino cache stuff */
1778 	struct btrfs_free_space_ctl *free_ino_ctl;
1779 	enum btrfs_caching_type cached;
1780 	spinlock_t cache_lock;
1781 	wait_queue_head_t cache_wait;
1782 	struct btrfs_free_space_ctl *free_ino_pinned;
1783 	u64 cache_progress;
1784 	struct inode *cache_inode;
1785 
1786 	struct mutex log_mutex;
1787 	wait_queue_head_t log_writer_wait;
1788 	wait_queue_head_t log_commit_wait[2];
1789 	struct list_head log_ctxs[2];
1790 	atomic_t log_writers;
1791 	atomic_t log_commit[2];
1792 	atomic_t log_batch;
1793 	int log_transid;
1794 	/* No matter the commit succeeds or not*/
1795 	int log_transid_committed;
1796 	/* Just be updated when the commit succeeds. */
1797 	int last_log_commit;
1798 	pid_t log_start_pid;
1799 
1800 	u64 objectid;
1801 	u64 last_trans;
1802 
1803 	/* data allocations are done in sectorsize units */
1804 	u32 sectorsize;
1805 
1806 	/* node allocations are done in nodesize units */
1807 	u32 nodesize;
1808 
1809 	/* leaf allocations are done in leafsize units */
1810 	u32 leafsize;
1811 
1812 	u32 stripesize;
1813 
1814 	u32 type;
1815 
1816 	u64 highest_objectid;
1817 
1818 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
1819 	u64 alloc_bytenr;
1820 #endif
1821 
1822 	u64 defrag_trans_start;
1823 	struct btrfs_key defrag_progress;
1824 	struct btrfs_key defrag_max;
1825 	char *name;
1826 
1827 	/* the dirty list is only used by non-reference counted roots */
1828 	struct list_head dirty_list;
1829 
1830 	struct list_head root_list;
1831 
1832 	spinlock_t log_extents_lock[2];
1833 	struct list_head logged_list[2];
1834 
1835 	spinlock_t orphan_lock;
1836 	atomic_t orphan_inodes;
1837 	struct btrfs_block_rsv *orphan_block_rsv;
1838 	int orphan_cleanup_state;
1839 
1840 	spinlock_t inode_lock;
1841 	/* red-black tree that keeps track of in-memory inodes */
1842 	struct rb_root inode_tree;
1843 
1844 	/*
1845 	 * radix tree that keeps track of delayed nodes of every inode,
1846 	 * protected by inode_lock
1847 	 */
1848 	struct radix_tree_root delayed_nodes_tree;
1849 	/*
1850 	 * right now this just gets used so that a root has its own devid
1851 	 * for stat.  It may be used for more later
1852 	 */
1853 	dev_t anon_dev;
1854 
1855 	spinlock_t root_item_lock;
1856 	atomic_t refs;
1857 
1858 	struct mutex delalloc_mutex;
1859 	spinlock_t delalloc_lock;
1860 	/*
1861 	 * all of the inodes that have delalloc bytes.  It is possible for
1862 	 * this list to be empty even when there is still dirty data=ordered
1863 	 * extents waiting to finish IO.
1864 	 */
1865 	struct list_head delalloc_inodes;
1866 	struct list_head delalloc_root;
1867 	u64 nr_delalloc_inodes;
1868 
1869 	struct mutex ordered_extent_mutex;
1870 	/*
1871 	 * this is used by the balancing code to wait for all the pending
1872 	 * ordered extents
1873 	 */
1874 	spinlock_t ordered_extent_lock;
1875 
1876 	/*
1877 	 * all of the data=ordered extents pending writeback
1878 	 * these can span multiple transactions and basically include
1879 	 * every dirty data page that isn't from nodatacow
1880 	 */
1881 	struct list_head ordered_extents;
1882 	struct list_head ordered_root;
1883 	u64 nr_ordered_extents;
1884 
1885 	/*
1886 	 * Number of currently running SEND ioctls to prevent
1887 	 * manipulation with the read-only status via SUBVOL_SETFLAGS
1888 	 */
1889 	int send_in_progress;
1890 	struct btrfs_subvolume_writers *subv_writers;
1891 	atomic_t will_be_snapshoted;
1892 };
1893 
1894 struct btrfs_ioctl_defrag_range_args {
1895 	/* start of the defrag operation */
1896 	__u64 start;
1897 
1898 	/* number of bytes to defrag, use (u64)-1 to say all */
1899 	__u64 len;
1900 
1901 	/*
1902 	 * flags for the operation, which can include turning
1903 	 * on compression for this one defrag
1904 	 */
1905 	__u64 flags;
1906 
1907 	/*
1908 	 * any extent bigger than this will be considered
1909 	 * already defragged.  Use 0 to take the kernel default
1910 	 * Use 1 to say every single extent must be rewritten
1911 	 */
1912 	__u32 extent_thresh;
1913 
1914 	/*
1915 	 * which compression method to use if turning on compression
1916 	 * for this defrag operation.  If unspecified, zlib will
1917 	 * be used
1918 	 */
1919 	__u32 compress_type;
1920 
1921 	/* spare for later */
1922 	__u32 unused[4];
1923 };
1924 
1925 
1926 /*
1927  * inode items have the data typically returned from stat and store other
1928  * info about object characteristics.  There is one for every file and dir in
1929  * the FS
1930  */
1931 #define BTRFS_INODE_ITEM_KEY		1
1932 #define BTRFS_INODE_REF_KEY		12
1933 #define BTRFS_INODE_EXTREF_KEY		13
1934 #define BTRFS_XATTR_ITEM_KEY		24
1935 #define BTRFS_ORPHAN_ITEM_KEY		48
1936 /* reserve 2-15 close to the inode for later flexibility */
1937 
1938 /*
1939  * dir items are the name -> inode pointers in a directory.  There is one
1940  * for every name in a directory.
1941  */
1942 #define BTRFS_DIR_LOG_ITEM_KEY  60
1943 #define BTRFS_DIR_LOG_INDEX_KEY 72
1944 #define BTRFS_DIR_ITEM_KEY	84
1945 #define BTRFS_DIR_INDEX_KEY	96
1946 /*
1947  * extent data is for file data
1948  */
1949 #define BTRFS_EXTENT_DATA_KEY	108
1950 
1951 /*
1952  * extent csums are stored in a separate tree and hold csums for
1953  * an entire extent on disk.
1954  */
1955 #define BTRFS_EXTENT_CSUM_KEY	128
1956 
1957 /*
1958  * root items point to tree roots.  They are typically in the root
1959  * tree used by the super block to find all the other trees
1960  */
1961 #define BTRFS_ROOT_ITEM_KEY	132
1962 
1963 /*
1964  * root backrefs tie subvols and snapshots to the directory entries that
1965  * reference them
1966  */
1967 #define BTRFS_ROOT_BACKREF_KEY	144
1968 
1969 /*
1970  * root refs make a fast index for listing all of the snapshots and
1971  * subvolumes referenced by a given root.  They point directly to the
1972  * directory item in the root that references the subvol
1973  */
1974 #define BTRFS_ROOT_REF_KEY	156
1975 
1976 /*
1977  * extent items are in the extent map tree.  These record which blocks
1978  * are used, and how many references there are to each block
1979  */
1980 #define BTRFS_EXTENT_ITEM_KEY	168
1981 
1982 /*
1983  * The same as the BTRFS_EXTENT_ITEM_KEY, except it's metadata we already know
1984  * the length, so we save the level in key->offset instead of the length.
1985  */
1986 #define BTRFS_METADATA_ITEM_KEY	169
1987 
1988 #define BTRFS_TREE_BLOCK_REF_KEY	176
1989 
1990 #define BTRFS_EXTENT_DATA_REF_KEY	178
1991 
1992 #define BTRFS_EXTENT_REF_V0_KEY		180
1993 
1994 #define BTRFS_SHARED_BLOCK_REF_KEY	182
1995 
1996 #define BTRFS_SHARED_DATA_REF_KEY	184
1997 
1998 /*
1999  * block groups give us hints into the extent allocation trees.  Which
2000  * blocks are free etc etc
2001  */
2002 #define BTRFS_BLOCK_GROUP_ITEM_KEY 192
2003 
2004 #define BTRFS_DEV_EXTENT_KEY	204
2005 #define BTRFS_DEV_ITEM_KEY	216
2006 #define BTRFS_CHUNK_ITEM_KEY	228
2007 
2008 /*
2009  * Records the overall state of the qgroups.
2010  * There's only one instance of this key present,
2011  * (0, BTRFS_QGROUP_STATUS_KEY, 0)
2012  */
2013 #define BTRFS_QGROUP_STATUS_KEY         240
2014 /*
2015  * Records the currently used space of the qgroup.
2016  * One key per qgroup, (0, BTRFS_QGROUP_INFO_KEY, qgroupid).
2017  */
2018 #define BTRFS_QGROUP_INFO_KEY           242
2019 /*
2020  * Contains the user configured limits for the qgroup.
2021  * One key per qgroup, (0, BTRFS_QGROUP_LIMIT_KEY, qgroupid).
2022  */
2023 #define BTRFS_QGROUP_LIMIT_KEY          244
2024 /*
2025  * Records the child-parent relationship of qgroups. For
2026  * each relation, 2 keys are present:
2027  * (childid, BTRFS_QGROUP_RELATION_KEY, parentid)
2028  * (parentid, BTRFS_QGROUP_RELATION_KEY, childid)
2029  */
2030 #define BTRFS_QGROUP_RELATION_KEY       246
2031 
2032 #define BTRFS_BALANCE_ITEM_KEY	248
2033 
2034 /*
2035  * Persistantly stores the io stats in the device tree.
2036  * One key for all stats, (0, BTRFS_DEV_STATS_KEY, devid).
2037  */
2038 #define BTRFS_DEV_STATS_KEY	249
2039 
2040 /*
2041  * Persistantly stores the device replace state in the device tree.
2042  * The key is built like this: (0, BTRFS_DEV_REPLACE_KEY, 0).
2043  */
2044 #define BTRFS_DEV_REPLACE_KEY	250
2045 
2046 /*
2047  * Stores items that allow to quickly map UUIDs to something else.
2048  * These items are part of the filesystem UUID tree.
2049  * The key is built like this:
2050  * (UUID_upper_64_bits, BTRFS_UUID_KEY*, UUID_lower_64_bits).
2051  */
2052 #if BTRFS_UUID_SIZE != 16
2053 #error "UUID items require BTRFS_UUID_SIZE == 16!"
2054 #endif
2055 #define BTRFS_UUID_KEY_SUBVOL	251	/* for UUIDs assigned to subvols */
2056 #define BTRFS_UUID_KEY_RECEIVED_SUBVOL	252	/* for UUIDs assigned to
2057 						 * received subvols */
2058 
2059 /*
2060  * string items are for debugging.  They just store a short string of
2061  * data in the FS
2062  */
2063 #define BTRFS_STRING_ITEM_KEY	253
2064 
2065 /*
2066  * Flags for mount options.
2067  *
2068  * Note: don't forget to add new options to btrfs_show_options()
2069  */
2070 #define BTRFS_MOUNT_NODATASUM		(1 << 0)
2071 #define BTRFS_MOUNT_NODATACOW		(1 << 1)
2072 #define BTRFS_MOUNT_NOBARRIER		(1 << 2)
2073 #define BTRFS_MOUNT_SSD			(1 << 3)
2074 #define BTRFS_MOUNT_DEGRADED		(1 << 4)
2075 #define BTRFS_MOUNT_COMPRESS		(1 << 5)
2076 #define BTRFS_MOUNT_NOTREELOG           (1 << 6)
2077 #define BTRFS_MOUNT_FLUSHONCOMMIT       (1 << 7)
2078 #define BTRFS_MOUNT_SSD_SPREAD		(1 << 8)
2079 #define BTRFS_MOUNT_NOSSD		(1 << 9)
2080 #define BTRFS_MOUNT_DISCARD		(1 << 10)
2081 #define BTRFS_MOUNT_FORCE_COMPRESS      (1 << 11)
2082 #define BTRFS_MOUNT_SPACE_CACHE		(1 << 12)
2083 #define BTRFS_MOUNT_CLEAR_CACHE		(1 << 13)
2084 #define BTRFS_MOUNT_USER_SUBVOL_RM_ALLOWED (1 << 14)
2085 #define BTRFS_MOUNT_ENOSPC_DEBUG	 (1 << 15)
2086 #define BTRFS_MOUNT_AUTO_DEFRAG		(1 << 16)
2087 #define BTRFS_MOUNT_INODE_MAP_CACHE	(1 << 17)
2088 #define BTRFS_MOUNT_RECOVERY		(1 << 18)
2089 #define BTRFS_MOUNT_SKIP_BALANCE	(1 << 19)
2090 #define BTRFS_MOUNT_CHECK_INTEGRITY	(1 << 20)
2091 #define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21)
2092 #define BTRFS_MOUNT_PANIC_ON_FATAL_ERROR	(1 << 22)
2093 #define BTRFS_MOUNT_RESCAN_UUID_TREE	(1 << 23)
2094 #define	BTRFS_MOUNT_CHANGE_INODE_CACHE	(1 << 24)
2095 
2096 #define BTRFS_DEFAULT_COMMIT_INTERVAL	(30)
2097 
2098 #define btrfs_clear_opt(o, opt)		((o) &= ~BTRFS_MOUNT_##opt)
2099 #define btrfs_set_opt(o, opt)		((o) |= BTRFS_MOUNT_##opt)
2100 #define btrfs_raw_test_opt(o, opt)	((o) & BTRFS_MOUNT_##opt)
2101 #define btrfs_test_opt(root, opt)	((root)->fs_info->mount_opt & \
2102 					 BTRFS_MOUNT_##opt)
2103 #define btrfs_set_and_info(root, opt, fmt, args...)			\
2104 {									\
2105 	if (!btrfs_test_opt(root, opt))					\
2106 		btrfs_info(root->fs_info, fmt, ##args);			\
2107 	btrfs_set_opt(root->fs_info->mount_opt, opt);			\
2108 }
2109 
2110 #define btrfs_clear_and_info(root, opt, fmt, args...)			\
2111 {									\
2112 	if (btrfs_test_opt(root, opt))					\
2113 		btrfs_info(root->fs_info, fmt, ##args);			\
2114 	btrfs_clear_opt(root->fs_info->mount_opt, opt);			\
2115 }
2116 
2117 /*
2118  * Inode flags
2119  */
2120 #define BTRFS_INODE_NODATASUM		(1 << 0)
2121 #define BTRFS_INODE_NODATACOW		(1 << 1)
2122 #define BTRFS_INODE_READONLY		(1 << 2)
2123 #define BTRFS_INODE_NOCOMPRESS		(1 << 3)
2124 #define BTRFS_INODE_PREALLOC		(1 << 4)
2125 #define BTRFS_INODE_SYNC		(1 << 5)
2126 #define BTRFS_INODE_IMMUTABLE		(1 << 6)
2127 #define BTRFS_INODE_APPEND		(1 << 7)
2128 #define BTRFS_INODE_NODUMP		(1 << 8)
2129 #define BTRFS_INODE_NOATIME		(1 << 9)
2130 #define BTRFS_INODE_DIRSYNC		(1 << 10)
2131 #define BTRFS_INODE_COMPRESS		(1 << 11)
2132 
2133 #define BTRFS_INODE_ROOT_ITEM_INIT	(1 << 31)
2134 
2135 struct btrfs_map_token {
2136 	struct extent_buffer *eb;
2137 	char *kaddr;
2138 	unsigned long offset;
2139 };
2140 
2141 static inline void btrfs_init_map_token (struct btrfs_map_token *token)
2142 {
2143 	token->kaddr = NULL;
2144 }
2145 
2146 /* some macros to generate set/get funcs for the struct fields.  This
2147  * assumes there is a lefoo_to_cpu for every type, so lets make a simple
2148  * one for u8:
2149  */
2150 #define le8_to_cpu(v) (v)
2151 #define cpu_to_le8(v) (v)
2152 #define __le8 u8
2153 
2154 #define read_eb_member(eb, ptr, type, member, result) (			\
2155 	read_extent_buffer(eb, (char *)(result),			\
2156 			   ((unsigned long)(ptr)) +			\
2157 			    offsetof(type, member),			\
2158 			   sizeof(((type *)0)->member)))
2159 
2160 #define write_eb_member(eb, ptr, type, member, result) (		\
2161 	write_extent_buffer(eb, (char *)(result),			\
2162 			   ((unsigned long)(ptr)) +			\
2163 			    offsetof(type, member),			\
2164 			   sizeof(((type *)0)->member)))
2165 
2166 #define DECLARE_BTRFS_SETGET_BITS(bits)					\
2167 u##bits btrfs_get_token_##bits(struct extent_buffer *eb, void *ptr,	\
2168 			       unsigned long off,			\
2169                               struct btrfs_map_token *token);		\
2170 void btrfs_set_token_##bits(struct extent_buffer *eb, void *ptr,	\
2171 			    unsigned long off, u##bits val,		\
2172 			    struct btrfs_map_token *token);		\
2173 static inline u##bits btrfs_get_##bits(struct extent_buffer *eb, void *ptr, \
2174 				       unsigned long off)		\
2175 {									\
2176 	return btrfs_get_token_##bits(eb, ptr, off, NULL);		\
2177 }									\
2178 static inline void btrfs_set_##bits(struct extent_buffer *eb, void *ptr, \
2179 				    unsigned long off, u##bits val)	\
2180 {									\
2181        btrfs_set_token_##bits(eb, ptr, off, val, NULL);			\
2182 }
2183 
2184 DECLARE_BTRFS_SETGET_BITS(8)
2185 DECLARE_BTRFS_SETGET_BITS(16)
2186 DECLARE_BTRFS_SETGET_BITS(32)
2187 DECLARE_BTRFS_SETGET_BITS(64)
2188 
2189 #define BTRFS_SETGET_FUNCS(name, type, member, bits)			\
2190 static inline u##bits btrfs_##name(struct extent_buffer *eb, type *s)	\
2191 {									\
2192 	BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member);	\
2193 	return btrfs_get_##bits(eb, s, offsetof(type, member));		\
2194 }									\
2195 static inline void btrfs_set_##name(struct extent_buffer *eb, type *s,	\
2196 				    u##bits val)			\
2197 {									\
2198 	BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member);	\
2199 	btrfs_set_##bits(eb, s, offsetof(type, member), val);		\
2200 }									\
2201 static inline u##bits btrfs_token_##name(struct extent_buffer *eb, type *s, \
2202 					 struct btrfs_map_token *token)	\
2203 {									\
2204 	BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member);	\
2205 	return btrfs_get_token_##bits(eb, s, offsetof(type, member), token); \
2206 }									\
2207 static inline void btrfs_set_token_##name(struct extent_buffer *eb,	\
2208 					  type *s, u##bits val,		\
2209                                          struct btrfs_map_token *token)	\
2210 {									\
2211 	BUILD_BUG_ON(sizeof(u##bits) != sizeof(((type *)0))->member);	\
2212 	btrfs_set_token_##bits(eb, s, offsetof(type, member), val, token); \
2213 }
2214 
2215 #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits)		\
2216 static inline u##bits btrfs_##name(struct extent_buffer *eb)		\
2217 {									\
2218 	type *p = page_address(eb->pages[0]);				\
2219 	u##bits res = le##bits##_to_cpu(p->member);			\
2220 	return res;							\
2221 }									\
2222 static inline void btrfs_set_##name(struct extent_buffer *eb,		\
2223 				    u##bits val)			\
2224 {									\
2225 	type *p = page_address(eb->pages[0]);				\
2226 	p->member = cpu_to_le##bits(val);				\
2227 }
2228 
2229 #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits)		\
2230 static inline u##bits btrfs_##name(type *s)				\
2231 {									\
2232 	return le##bits##_to_cpu(s->member);				\
2233 }									\
2234 static inline void btrfs_set_##name(type *s, u##bits val)		\
2235 {									\
2236 	s->member = cpu_to_le##bits(val);				\
2237 }
2238 
2239 BTRFS_SETGET_FUNCS(device_type, struct btrfs_dev_item, type, 64);
2240 BTRFS_SETGET_FUNCS(device_total_bytes, struct btrfs_dev_item, total_bytes, 64);
2241 BTRFS_SETGET_FUNCS(device_bytes_used, struct btrfs_dev_item, bytes_used, 64);
2242 BTRFS_SETGET_FUNCS(device_io_align, struct btrfs_dev_item, io_align, 32);
2243 BTRFS_SETGET_FUNCS(device_io_width, struct btrfs_dev_item, io_width, 32);
2244 BTRFS_SETGET_FUNCS(device_start_offset, struct btrfs_dev_item,
2245 		   start_offset, 64);
2246 BTRFS_SETGET_FUNCS(device_sector_size, struct btrfs_dev_item, sector_size, 32);
2247 BTRFS_SETGET_FUNCS(device_id, struct btrfs_dev_item, devid, 64);
2248 BTRFS_SETGET_FUNCS(device_group, struct btrfs_dev_item, dev_group, 32);
2249 BTRFS_SETGET_FUNCS(device_seek_speed, struct btrfs_dev_item, seek_speed, 8);
2250 BTRFS_SETGET_FUNCS(device_bandwidth, struct btrfs_dev_item, bandwidth, 8);
2251 BTRFS_SETGET_FUNCS(device_generation, struct btrfs_dev_item, generation, 64);
2252 
2253 BTRFS_SETGET_STACK_FUNCS(stack_device_type, struct btrfs_dev_item, type, 64);
2254 BTRFS_SETGET_STACK_FUNCS(stack_device_total_bytes, struct btrfs_dev_item,
2255 			 total_bytes, 64);
2256 BTRFS_SETGET_STACK_FUNCS(stack_device_bytes_used, struct btrfs_dev_item,
2257 			 bytes_used, 64);
2258 BTRFS_SETGET_STACK_FUNCS(stack_device_io_align, struct btrfs_dev_item,
2259 			 io_align, 32);
2260 BTRFS_SETGET_STACK_FUNCS(stack_device_io_width, struct btrfs_dev_item,
2261 			 io_width, 32);
2262 BTRFS_SETGET_STACK_FUNCS(stack_device_sector_size, struct btrfs_dev_item,
2263 			 sector_size, 32);
2264 BTRFS_SETGET_STACK_FUNCS(stack_device_id, struct btrfs_dev_item, devid, 64);
2265 BTRFS_SETGET_STACK_FUNCS(stack_device_group, struct btrfs_dev_item,
2266 			 dev_group, 32);
2267 BTRFS_SETGET_STACK_FUNCS(stack_device_seek_speed, struct btrfs_dev_item,
2268 			 seek_speed, 8);
2269 BTRFS_SETGET_STACK_FUNCS(stack_device_bandwidth, struct btrfs_dev_item,
2270 			 bandwidth, 8);
2271 BTRFS_SETGET_STACK_FUNCS(stack_device_generation, struct btrfs_dev_item,
2272 			 generation, 64);
2273 
2274 static inline unsigned long btrfs_device_uuid(struct btrfs_dev_item *d)
2275 {
2276 	return (unsigned long)d + offsetof(struct btrfs_dev_item, uuid);
2277 }
2278 
2279 static inline unsigned long btrfs_device_fsid(struct btrfs_dev_item *d)
2280 {
2281 	return (unsigned long)d + offsetof(struct btrfs_dev_item, fsid);
2282 }
2283 
2284 BTRFS_SETGET_FUNCS(chunk_length, struct btrfs_chunk, length, 64);
2285 BTRFS_SETGET_FUNCS(chunk_owner, struct btrfs_chunk, owner, 64);
2286 BTRFS_SETGET_FUNCS(chunk_stripe_len, struct btrfs_chunk, stripe_len, 64);
2287 BTRFS_SETGET_FUNCS(chunk_io_align, struct btrfs_chunk, io_align, 32);
2288 BTRFS_SETGET_FUNCS(chunk_io_width, struct btrfs_chunk, io_width, 32);
2289 BTRFS_SETGET_FUNCS(chunk_sector_size, struct btrfs_chunk, sector_size, 32);
2290 BTRFS_SETGET_FUNCS(chunk_type, struct btrfs_chunk, type, 64);
2291 BTRFS_SETGET_FUNCS(chunk_num_stripes, struct btrfs_chunk, num_stripes, 16);
2292 BTRFS_SETGET_FUNCS(chunk_sub_stripes, struct btrfs_chunk, sub_stripes, 16);
2293 BTRFS_SETGET_FUNCS(stripe_devid, struct btrfs_stripe, devid, 64);
2294 BTRFS_SETGET_FUNCS(stripe_offset, struct btrfs_stripe, offset, 64);
2295 
2296 static inline char *btrfs_stripe_dev_uuid(struct btrfs_stripe *s)
2297 {
2298 	return (char *)s + offsetof(struct btrfs_stripe, dev_uuid);
2299 }
2300 
2301 BTRFS_SETGET_STACK_FUNCS(stack_chunk_length, struct btrfs_chunk, length, 64);
2302 BTRFS_SETGET_STACK_FUNCS(stack_chunk_owner, struct btrfs_chunk, owner, 64);
2303 BTRFS_SETGET_STACK_FUNCS(stack_chunk_stripe_len, struct btrfs_chunk,
2304 			 stripe_len, 64);
2305 BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_align, struct btrfs_chunk,
2306 			 io_align, 32);
2307 BTRFS_SETGET_STACK_FUNCS(stack_chunk_io_width, struct btrfs_chunk,
2308 			 io_width, 32);
2309 BTRFS_SETGET_STACK_FUNCS(stack_chunk_sector_size, struct btrfs_chunk,
2310 			 sector_size, 32);
2311 BTRFS_SETGET_STACK_FUNCS(stack_chunk_type, struct btrfs_chunk, type, 64);
2312 BTRFS_SETGET_STACK_FUNCS(stack_chunk_num_stripes, struct btrfs_chunk,
2313 			 num_stripes, 16);
2314 BTRFS_SETGET_STACK_FUNCS(stack_chunk_sub_stripes, struct btrfs_chunk,
2315 			 sub_stripes, 16);
2316 BTRFS_SETGET_STACK_FUNCS(stack_stripe_devid, struct btrfs_stripe, devid, 64);
2317 BTRFS_SETGET_STACK_FUNCS(stack_stripe_offset, struct btrfs_stripe, offset, 64);
2318 
2319 static inline struct btrfs_stripe *btrfs_stripe_nr(struct btrfs_chunk *c,
2320 						   int nr)
2321 {
2322 	unsigned long offset = (unsigned long)c;
2323 	offset += offsetof(struct btrfs_chunk, stripe);
2324 	offset += nr * sizeof(struct btrfs_stripe);
2325 	return (struct btrfs_stripe *)offset;
2326 }
2327 
2328 static inline char *btrfs_stripe_dev_uuid_nr(struct btrfs_chunk *c, int nr)
2329 {
2330 	return btrfs_stripe_dev_uuid(btrfs_stripe_nr(c, nr));
2331 }
2332 
2333 static inline u64 btrfs_stripe_offset_nr(struct extent_buffer *eb,
2334 					 struct btrfs_chunk *c, int nr)
2335 {
2336 	return btrfs_stripe_offset(eb, btrfs_stripe_nr(c, nr));
2337 }
2338 
2339 static inline u64 btrfs_stripe_devid_nr(struct extent_buffer *eb,
2340 					 struct btrfs_chunk *c, int nr)
2341 {
2342 	return btrfs_stripe_devid(eb, btrfs_stripe_nr(c, nr));
2343 }
2344 
2345 /* struct btrfs_block_group_item */
2346 BTRFS_SETGET_STACK_FUNCS(block_group_used, struct btrfs_block_group_item,
2347 			 used, 64);
2348 BTRFS_SETGET_FUNCS(disk_block_group_used, struct btrfs_block_group_item,
2349 			 used, 64);
2350 BTRFS_SETGET_STACK_FUNCS(block_group_chunk_objectid,
2351 			struct btrfs_block_group_item, chunk_objectid, 64);
2352 
2353 BTRFS_SETGET_FUNCS(disk_block_group_chunk_objectid,
2354 		   struct btrfs_block_group_item, chunk_objectid, 64);
2355 BTRFS_SETGET_FUNCS(disk_block_group_flags,
2356 		   struct btrfs_block_group_item, flags, 64);
2357 BTRFS_SETGET_STACK_FUNCS(block_group_flags,
2358 			struct btrfs_block_group_item, flags, 64);
2359 
2360 /* struct btrfs_inode_ref */
2361 BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16);
2362 BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64);
2363 
2364 /* struct btrfs_inode_extref */
2365 BTRFS_SETGET_FUNCS(inode_extref_parent, struct btrfs_inode_extref,
2366 		   parent_objectid, 64);
2367 BTRFS_SETGET_FUNCS(inode_extref_name_len, struct btrfs_inode_extref,
2368 		   name_len, 16);
2369 BTRFS_SETGET_FUNCS(inode_extref_index, struct btrfs_inode_extref, index, 64);
2370 
2371 /* struct btrfs_inode_item */
2372 BTRFS_SETGET_FUNCS(inode_generation, struct btrfs_inode_item, generation, 64);
2373 BTRFS_SETGET_FUNCS(inode_sequence, struct btrfs_inode_item, sequence, 64);
2374 BTRFS_SETGET_FUNCS(inode_transid, struct btrfs_inode_item, transid, 64);
2375 BTRFS_SETGET_FUNCS(inode_size, struct btrfs_inode_item, size, 64);
2376 BTRFS_SETGET_FUNCS(inode_nbytes, struct btrfs_inode_item, nbytes, 64);
2377 BTRFS_SETGET_FUNCS(inode_block_group, struct btrfs_inode_item, block_group, 64);
2378 BTRFS_SETGET_FUNCS(inode_nlink, struct btrfs_inode_item, nlink, 32);
2379 BTRFS_SETGET_FUNCS(inode_uid, struct btrfs_inode_item, uid, 32);
2380 BTRFS_SETGET_FUNCS(inode_gid, struct btrfs_inode_item, gid, 32);
2381 BTRFS_SETGET_FUNCS(inode_mode, struct btrfs_inode_item, mode, 32);
2382 BTRFS_SETGET_FUNCS(inode_rdev, struct btrfs_inode_item, rdev, 64);
2383 BTRFS_SETGET_FUNCS(inode_flags, struct btrfs_inode_item, flags, 64);
2384 BTRFS_SETGET_STACK_FUNCS(stack_inode_generation, struct btrfs_inode_item,
2385 			 generation, 64);
2386 BTRFS_SETGET_STACK_FUNCS(stack_inode_sequence, struct btrfs_inode_item,
2387 			 sequence, 64);
2388 BTRFS_SETGET_STACK_FUNCS(stack_inode_transid, struct btrfs_inode_item,
2389 			 transid, 64);
2390 BTRFS_SETGET_STACK_FUNCS(stack_inode_size, struct btrfs_inode_item, size, 64);
2391 BTRFS_SETGET_STACK_FUNCS(stack_inode_nbytes, struct btrfs_inode_item,
2392 			 nbytes, 64);
2393 BTRFS_SETGET_STACK_FUNCS(stack_inode_block_group, struct btrfs_inode_item,
2394 			 block_group, 64);
2395 BTRFS_SETGET_STACK_FUNCS(stack_inode_nlink, struct btrfs_inode_item, nlink, 32);
2396 BTRFS_SETGET_STACK_FUNCS(stack_inode_uid, struct btrfs_inode_item, uid, 32);
2397 BTRFS_SETGET_STACK_FUNCS(stack_inode_gid, struct btrfs_inode_item, gid, 32);
2398 BTRFS_SETGET_STACK_FUNCS(stack_inode_mode, struct btrfs_inode_item, mode, 32);
2399 BTRFS_SETGET_STACK_FUNCS(stack_inode_rdev, struct btrfs_inode_item, rdev, 64);
2400 BTRFS_SETGET_STACK_FUNCS(stack_inode_flags, struct btrfs_inode_item, flags, 64);
2401 
2402 static inline struct btrfs_timespec *
2403 btrfs_inode_atime(struct btrfs_inode_item *inode_item)
2404 {
2405 	unsigned long ptr = (unsigned long)inode_item;
2406 	ptr += offsetof(struct btrfs_inode_item, atime);
2407 	return (struct btrfs_timespec *)ptr;
2408 }
2409 
2410 static inline struct btrfs_timespec *
2411 btrfs_inode_mtime(struct btrfs_inode_item *inode_item)
2412 {
2413 	unsigned long ptr = (unsigned long)inode_item;
2414 	ptr += offsetof(struct btrfs_inode_item, mtime);
2415 	return (struct btrfs_timespec *)ptr;
2416 }
2417 
2418 static inline struct btrfs_timespec *
2419 btrfs_inode_ctime(struct btrfs_inode_item *inode_item)
2420 {
2421 	unsigned long ptr = (unsigned long)inode_item;
2422 	ptr += offsetof(struct btrfs_inode_item, ctime);
2423 	return (struct btrfs_timespec *)ptr;
2424 }
2425 
2426 BTRFS_SETGET_FUNCS(timespec_sec, struct btrfs_timespec, sec, 64);
2427 BTRFS_SETGET_FUNCS(timespec_nsec, struct btrfs_timespec, nsec, 32);
2428 BTRFS_SETGET_STACK_FUNCS(stack_timespec_sec, struct btrfs_timespec, sec, 64);
2429 BTRFS_SETGET_STACK_FUNCS(stack_timespec_nsec, struct btrfs_timespec, nsec, 32);
2430 
2431 /* struct btrfs_dev_extent */
2432 BTRFS_SETGET_FUNCS(dev_extent_chunk_tree, struct btrfs_dev_extent,
2433 		   chunk_tree, 64);
2434 BTRFS_SETGET_FUNCS(dev_extent_chunk_objectid, struct btrfs_dev_extent,
2435 		   chunk_objectid, 64);
2436 BTRFS_SETGET_FUNCS(dev_extent_chunk_offset, struct btrfs_dev_extent,
2437 		   chunk_offset, 64);
2438 BTRFS_SETGET_FUNCS(dev_extent_length, struct btrfs_dev_extent, length, 64);
2439 
2440 static inline unsigned long btrfs_dev_extent_chunk_tree_uuid(struct btrfs_dev_extent *dev)
2441 {
2442 	unsigned long ptr = offsetof(struct btrfs_dev_extent, chunk_tree_uuid);
2443 	return (unsigned long)dev + ptr;
2444 }
2445 
2446 BTRFS_SETGET_FUNCS(extent_refs, struct btrfs_extent_item, refs, 64);
2447 BTRFS_SETGET_FUNCS(extent_generation, struct btrfs_extent_item,
2448 		   generation, 64);
2449 BTRFS_SETGET_FUNCS(extent_flags, struct btrfs_extent_item, flags, 64);
2450 
2451 BTRFS_SETGET_FUNCS(extent_refs_v0, struct btrfs_extent_item_v0, refs, 32);
2452 
2453 
2454 BTRFS_SETGET_FUNCS(tree_block_level, struct btrfs_tree_block_info, level, 8);
2455 
2456 static inline void btrfs_tree_block_key(struct extent_buffer *eb,
2457 					struct btrfs_tree_block_info *item,
2458 					struct btrfs_disk_key *key)
2459 {
2460 	read_eb_member(eb, item, struct btrfs_tree_block_info, key, key);
2461 }
2462 
2463 static inline void btrfs_set_tree_block_key(struct extent_buffer *eb,
2464 					    struct btrfs_tree_block_info *item,
2465 					    struct btrfs_disk_key *key)
2466 {
2467 	write_eb_member(eb, item, struct btrfs_tree_block_info, key, key);
2468 }
2469 
2470 BTRFS_SETGET_FUNCS(extent_data_ref_root, struct btrfs_extent_data_ref,
2471 		   root, 64);
2472 BTRFS_SETGET_FUNCS(extent_data_ref_objectid, struct btrfs_extent_data_ref,
2473 		   objectid, 64);
2474 BTRFS_SETGET_FUNCS(extent_data_ref_offset, struct btrfs_extent_data_ref,
2475 		   offset, 64);
2476 BTRFS_SETGET_FUNCS(extent_data_ref_count, struct btrfs_extent_data_ref,
2477 		   count, 32);
2478 
2479 BTRFS_SETGET_FUNCS(shared_data_ref_count, struct btrfs_shared_data_ref,
2480 		   count, 32);
2481 
2482 BTRFS_SETGET_FUNCS(extent_inline_ref_type, struct btrfs_extent_inline_ref,
2483 		   type, 8);
2484 BTRFS_SETGET_FUNCS(extent_inline_ref_offset, struct btrfs_extent_inline_ref,
2485 		   offset, 64);
2486 
2487 static inline u32 btrfs_extent_inline_ref_size(int type)
2488 {
2489 	if (type == BTRFS_TREE_BLOCK_REF_KEY ||
2490 	    type == BTRFS_SHARED_BLOCK_REF_KEY)
2491 		return sizeof(struct btrfs_extent_inline_ref);
2492 	if (type == BTRFS_SHARED_DATA_REF_KEY)
2493 		return sizeof(struct btrfs_shared_data_ref) +
2494 		       sizeof(struct btrfs_extent_inline_ref);
2495 	if (type == BTRFS_EXTENT_DATA_REF_KEY)
2496 		return sizeof(struct btrfs_extent_data_ref) +
2497 		       offsetof(struct btrfs_extent_inline_ref, offset);
2498 	BUG();
2499 	return 0;
2500 }
2501 
2502 BTRFS_SETGET_FUNCS(ref_root_v0, struct btrfs_extent_ref_v0, root, 64);
2503 BTRFS_SETGET_FUNCS(ref_generation_v0, struct btrfs_extent_ref_v0,
2504 		   generation, 64);
2505 BTRFS_SETGET_FUNCS(ref_objectid_v0, struct btrfs_extent_ref_v0, objectid, 64);
2506 BTRFS_SETGET_FUNCS(ref_count_v0, struct btrfs_extent_ref_v0, count, 32);
2507 
2508 /* struct btrfs_node */
2509 BTRFS_SETGET_FUNCS(key_blockptr, struct btrfs_key_ptr, blockptr, 64);
2510 BTRFS_SETGET_FUNCS(key_generation, struct btrfs_key_ptr, generation, 64);
2511 BTRFS_SETGET_STACK_FUNCS(stack_key_blockptr, struct btrfs_key_ptr,
2512 			 blockptr, 64);
2513 BTRFS_SETGET_STACK_FUNCS(stack_key_generation, struct btrfs_key_ptr,
2514 			 generation, 64);
2515 
2516 static inline u64 btrfs_node_blockptr(struct extent_buffer *eb, int nr)
2517 {
2518 	unsigned long ptr;
2519 	ptr = offsetof(struct btrfs_node, ptrs) +
2520 		sizeof(struct btrfs_key_ptr) * nr;
2521 	return btrfs_key_blockptr(eb, (struct btrfs_key_ptr *)ptr);
2522 }
2523 
2524 static inline void btrfs_set_node_blockptr(struct extent_buffer *eb,
2525 					   int nr, u64 val)
2526 {
2527 	unsigned long ptr;
2528 	ptr = offsetof(struct btrfs_node, ptrs) +
2529 		sizeof(struct btrfs_key_ptr) * nr;
2530 	btrfs_set_key_blockptr(eb, (struct btrfs_key_ptr *)ptr, val);
2531 }
2532 
2533 static inline u64 btrfs_node_ptr_generation(struct extent_buffer *eb, int nr)
2534 {
2535 	unsigned long ptr;
2536 	ptr = offsetof(struct btrfs_node, ptrs) +
2537 		sizeof(struct btrfs_key_ptr) * nr;
2538 	return btrfs_key_generation(eb, (struct btrfs_key_ptr *)ptr);
2539 }
2540 
2541 static inline void btrfs_set_node_ptr_generation(struct extent_buffer *eb,
2542 						 int nr, u64 val)
2543 {
2544 	unsigned long ptr;
2545 	ptr = offsetof(struct btrfs_node, ptrs) +
2546 		sizeof(struct btrfs_key_ptr) * nr;
2547 	btrfs_set_key_generation(eb, (struct btrfs_key_ptr *)ptr, val);
2548 }
2549 
2550 static inline unsigned long btrfs_node_key_ptr_offset(int nr)
2551 {
2552 	return offsetof(struct btrfs_node, ptrs) +
2553 		sizeof(struct btrfs_key_ptr) * nr;
2554 }
2555 
2556 void btrfs_node_key(struct extent_buffer *eb,
2557 		    struct btrfs_disk_key *disk_key, int nr);
2558 
2559 static inline void btrfs_set_node_key(struct extent_buffer *eb,
2560 				      struct btrfs_disk_key *disk_key, int nr)
2561 {
2562 	unsigned long ptr;
2563 	ptr = btrfs_node_key_ptr_offset(nr);
2564 	write_eb_member(eb, (struct btrfs_key_ptr *)ptr,
2565 		       struct btrfs_key_ptr, key, disk_key);
2566 }
2567 
2568 /* struct btrfs_item */
2569 BTRFS_SETGET_FUNCS(item_offset, struct btrfs_item, offset, 32);
2570 BTRFS_SETGET_FUNCS(item_size, struct btrfs_item, size, 32);
2571 BTRFS_SETGET_STACK_FUNCS(stack_item_offset, struct btrfs_item, offset, 32);
2572 BTRFS_SETGET_STACK_FUNCS(stack_item_size, struct btrfs_item, size, 32);
2573 
2574 static inline unsigned long btrfs_item_nr_offset(int nr)
2575 {
2576 	return offsetof(struct btrfs_leaf, items) +
2577 		sizeof(struct btrfs_item) * nr;
2578 }
2579 
2580 static inline struct btrfs_item *btrfs_item_nr(int nr)
2581 {
2582 	return (struct btrfs_item *)btrfs_item_nr_offset(nr);
2583 }
2584 
2585 static inline u32 btrfs_item_end(struct extent_buffer *eb,
2586 				 struct btrfs_item *item)
2587 {
2588 	return btrfs_item_offset(eb, item) + btrfs_item_size(eb, item);
2589 }
2590 
2591 static inline u32 btrfs_item_end_nr(struct extent_buffer *eb, int nr)
2592 {
2593 	return btrfs_item_end(eb, btrfs_item_nr(nr));
2594 }
2595 
2596 static inline u32 btrfs_item_offset_nr(struct extent_buffer *eb, int nr)
2597 {
2598 	return btrfs_item_offset(eb, btrfs_item_nr(nr));
2599 }
2600 
2601 static inline u32 btrfs_item_size_nr(struct extent_buffer *eb, int nr)
2602 {
2603 	return btrfs_item_size(eb, btrfs_item_nr(nr));
2604 }
2605 
2606 static inline void btrfs_item_key(struct extent_buffer *eb,
2607 			   struct btrfs_disk_key *disk_key, int nr)
2608 {
2609 	struct btrfs_item *item = btrfs_item_nr(nr);
2610 	read_eb_member(eb, item, struct btrfs_item, key, disk_key);
2611 }
2612 
2613 static inline void btrfs_set_item_key(struct extent_buffer *eb,
2614 			       struct btrfs_disk_key *disk_key, int nr)
2615 {
2616 	struct btrfs_item *item = btrfs_item_nr(nr);
2617 	write_eb_member(eb, item, struct btrfs_item, key, disk_key);
2618 }
2619 
2620 BTRFS_SETGET_FUNCS(dir_log_end, struct btrfs_dir_log_item, end, 64);
2621 
2622 /*
2623  * struct btrfs_root_ref
2624  */
2625 BTRFS_SETGET_FUNCS(root_ref_dirid, struct btrfs_root_ref, dirid, 64);
2626 BTRFS_SETGET_FUNCS(root_ref_sequence, struct btrfs_root_ref, sequence, 64);
2627 BTRFS_SETGET_FUNCS(root_ref_name_len, struct btrfs_root_ref, name_len, 16);
2628 
2629 /* struct btrfs_dir_item */
2630 BTRFS_SETGET_FUNCS(dir_data_len, struct btrfs_dir_item, data_len, 16);
2631 BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8);
2632 BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16);
2633 BTRFS_SETGET_FUNCS(dir_transid, struct btrfs_dir_item, transid, 64);
2634 BTRFS_SETGET_STACK_FUNCS(stack_dir_type, struct btrfs_dir_item, type, 8);
2635 BTRFS_SETGET_STACK_FUNCS(stack_dir_data_len, struct btrfs_dir_item,
2636 			 data_len, 16);
2637 BTRFS_SETGET_STACK_FUNCS(stack_dir_name_len, struct btrfs_dir_item,
2638 			 name_len, 16);
2639 BTRFS_SETGET_STACK_FUNCS(stack_dir_transid, struct btrfs_dir_item,
2640 			 transid, 64);
2641 
2642 static inline void btrfs_dir_item_key(struct extent_buffer *eb,
2643 				      struct btrfs_dir_item *item,
2644 				      struct btrfs_disk_key *key)
2645 {
2646 	read_eb_member(eb, item, struct btrfs_dir_item, location, key);
2647 }
2648 
2649 static inline void btrfs_set_dir_item_key(struct extent_buffer *eb,
2650 					  struct btrfs_dir_item *item,
2651 					  struct btrfs_disk_key *key)
2652 {
2653 	write_eb_member(eb, item, struct btrfs_dir_item, location, key);
2654 }
2655 
2656 BTRFS_SETGET_FUNCS(free_space_entries, struct btrfs_free_space_header,
2657 		   num_entries, 64);
2658 BTRFS_SETGET_FUNCS(free_space_bitmaps, struct btrfs_free_space_header,
2659 		   num_bitmaps, 64);
2660 BTRFS_SETGET_FUNCS(free_space_generation, struct btrfs_free_space_header,
2661 		   generation, 64);
2662 
2663 static inline void btrfs_free_space_key(struct extent_buffer *eb,
2664 					struct btrfs_free_space_header *h,
2665 					struct btrfs_disk_key *key)
2666 {
2667 	read_eb_member(eb, h, struct btrfs_free_space_header, location, key);
2668 }
2669 
2670 static inline void btrfs_set_free_space_key(struct extent_buffer *eb,
2671 					    struct btrfs_free_space_header *h,
2672 					    struct btrfs_disk_key *key)
2673 {
2674 	write_eb_member(eb, h, struct btrfs_free_space_header, location, key);
2675 }
2676 
2677 /* struct btrfs_disk_key */
2678 BTRFS_SETGET_STACK_FUNCS(disk_key_objectid, struct btrfs_disk_key,
2679 			 objectid, 64);
2680 BTRFS_SETGET_STACK_FUNCS(disk_key_offset, struct btrfs_disk_key, offset, 64);
2681 BTRFS_SETGET_STACK_FUNCS(disk_key_type, struct btrfs_disk_key, type, 8);
2682 
2683 static inline void btrfs_disk_key_to_cpu(struct btrfs_key *cpu,
2684 					 struct btrfs_disk_key *disk)
2685 {
2686 	cpu->offset = le64_to_cpu(disk->offset);
2687 	cpu->type = disk->type;
2688 	cpu->objectid = le64_to_cpu(disk->objectid);
2689 }
2690 
2691 static inline void btrfs_cpu_key_to_disk(struct btrfs_disk_key *disk,
2692 					 struct btrfs_key *cpu)
2693 {
2694 	disk->offset = cpu_to_le64(cpu->offset);
2695 	disk->type = cpu->type;
2696 	disk->objectid = cpu_to_le64(cpu->objectid);
2697 }
2698 
2699 static inline void btrfs_node_key_to_cpu(struct extent_buffer *eb,
2700 				  struct btrfs_key *key, int nr)
2701 {
2702 	struct btrfs_disk_key disk_key;
2703 	btrfs_node_key(eb, &disk_key, nr);
2704 	btrfs_disk_key_to_cpu(key, &disk_key);
2705 }
2706 
2707 static inline void btrfs_item_key_to_cpu(struct extent_buffer *eb,
2708 				  struct btrfs_key *key, int nr)
2709 {
2710 	struct btrfs_disk_key disk_key;
2711 	btrfs_item_key(eb, &disk_key, nr);
2712 	btrfs_disk_key_to_cpu(key, &disk_key);
2713 }
2714 
2715 static inline void btrfs_dir_item_key_to_cpu(struct extent_buffer *eb,
2716 				      struct btrfs_dir_item *item,
2717 				      struct btrfs_key *key)
2718 {
2719 	struct btrfs_disk_key disk_key;
2720 	btrfs_dir_item_key(eb, item, &disk_key);
2721 	btrfs_disk_key_to_cpu(key, &disk_key);
2722 }
2723 
2724 
2725 static inline u8 btrfs_key_type(struct btrfs_key *key)
2726 {
2727 	return key->type;
2728 }
2729 
2730 static inline void btrfs_set_key_type(struct btrfs_key *key, u8 val)
2731 {
2732 	key->type = val;
2733 }
2734 
2735 /* struct btrfs_header */
2736 BTRFS_SETGET_HEADER_FUNCS(header_bytenr, struct btrfs_header, bytenr, 64);
2737 BTRFS_SETGET_HEADER_FUNCS(header_generation, struct btrfs_header,
2738 			  generation, 64);
2739 BTRFS_SETGET_HEADER_FUNCS(header_owner, struct btrfs_header, owner, 64);
2740 BTRFS_SETGET_HEADER_FUNCS(header_nritems, struct btrfs_header, nritems, 32);
2741 BTRFS_SETGET_HEADER_FUNCS(header_flags, struct btrfs_header, flags, 64);
2742 BTRFS_SETGET_HEADER_FUNCS(header_level, struct btrfs_header, level, 8);
2743 BTRFS_SETGET_STACK_FUNCS(stack_header_generation, struct btrfs_header,
2744 			 generation, 64);
2745 BTRFS_SETGET_STACK_FUNCS(stack_header_owner, struct btrfs_header, owner, 64);
2746 BTRFS_SETGET_STACK_FUNCS(stack_header_nritems, struct btrfs_header,
2747 			 nritems, 32);
2748 BTRFS_SETGET_STACK_FUNCS(stack_header_bytenr, struct btrfs_header, bytenr, 64);
2749 
2750 static inline int btrfs_header_flag(struct extent_buffer *eb, u64 flag)
2751 {
2752 	return (btrfs_header_flags(eb) & flag) == flag;
2753 }
2754 
2755 static inline int btrfs_set_header_flag(struct extent_buffer *eb, u64 flag)
2756 {
2757 	u64 flags = btrfs_header_flags(eb);
2758 	btrfs_set_header_flags(eb, flags | flag);
2759 	return (flags & flag) == flag;
2760 }
2761 
2762 static inline int btrfs_clear_header_flag(struct extent_buffer *eb, u64 flag)
2763 {
2764 	u64 flags = btrfs_header_flags(eb);
2765 	btrfs_set_header_flags(eb, flags & ~flag);
2766 	return (flags & flag) == flag;
2767 }
2768 
2769 static inline int btrfs_header_backref_rev(struct extent_buffer *eb)
2770 {
2771 	u64 flags = btrfs_header_flags(eb);
2772 	return flags >> BTRFS_BACKREF_REV_SHIFT;
2773 }
2774 
2775 static inline void btrfs_set_header_backref_rev(struct extent_buffer *eb,
2776 						int rev)
2777 {
2778 	u64 flags = btrfs_header_flags(eb);
2779 	flags &= ~BTRFS_BACKREF_REV_MASK;
2780 	flags |= (u64)rev << BTRFS_BACKREF_REV_SHIFT;
2781 	btrfs_set_header_flags(eb, flags);
2782 }
2783 
2784 static inline unsigned long btrfs_header_fsid(void)
2785 {
2786 	return offsetof(struct btrfs_header, fsid);
2787 }
2788 
2789 static inline unsigned long btrfs_header_chunk_tree_uuid(struct extent_buffer *eb)
2790 {
2791 	return offsetof(struct btrfs_header, chunk_tree_uuid);
2792 }
2793 
2794 static inline int btrfs_is_leaf(struct extent_buffer *eb)
2795 {
2796 	return btrfs_header_level(eb) == 0;
2797 }
2798 
2799 /* struct btrfs_root_item */
2800 BTRFS_SETGET_FUNCS(disk_root_generation, struct btrfs_root_item,
2801 		   generation, 64);
2802 BTRFS_SETGET_FUNCS(disk_root_refs, struct btrfs_root_item, refs, 32);
2803 BTRFS_SETGET_FUNCS(disk_root_bytenr, struct btrfs_root_item, bytenr, 64);
2804 BTRFS_SETGET_FUNCS(disk_root_level, struct btrfs_root_item, level, 8);
2805 
2806 BTRFS_SETGET_STACK_FUNCS(root_generation, struct btrfs_root_item,
2807 			 generation, 64);
2808 BTRFS_SETGET_STACK_FUNCS(root_bytenr, struct btrfs_root_item, bytenr, 64);
2809 BTRFS_SETGET_STACK_FUNCS(root_level, struct btrfs_root_item, level, 8);
2810 BTRFS_SETGET_STACK_FUNCS(root_dirid, struct btrfs_root_item, root_dirid, 64);
2811 BTRFS_SETGET_STACK_FUNCS(root_refs, struct btrfs_root_item, refs, 32);
2812 BTRFS_SETGET_STACK_FUNCS(root_flags, struct btrfs_root_item, flags, 64);
2813 BTRFS_SETGET_STACK_FUNCS(root_used, struct btrfs_root_item, bytes_used, 64);
2814 BTRFS_SETGET_STACK_FUNCS(root_limit, struct btrfs_root_item, byte_limit, 64);
2815 BTRFS_SETGET_STACK_FUNCS(root_last_snapshot, struct btrfs_root_item,
2816 			 last_snapshot, 64);
2817 BTRFS_SETGET_STACK_FUNCS(root_generation_v2, struct btrfs_root_item,
2818 			 generation_v2, 64);
2819 BTRFS_SETGET_STACK_FUNCS(root_ctransid, struct btrfs_root_item,
2820 			 ctransid, 64);
2821 BTRFS_SETGET_STACK_FUNCS(root_otransid, struct btrfs_root_item,
2822 			 otransid, 64);
2823 BTRFS_SETGET_STACK_FUNCS(root_stransid, struct btrfs_root_item,
2824 			 stransid, 64);
2825 BTRFS_SETGET_STACK_FUNCS(root_rtransid, struct btrfs_root_item,
2826 			 rtransid, 64);
2827 
2828 static inline bool btrfs_root_readonly(struct btrfs_root *root)
2829 {
2830 	return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_RDONLY)) != 0;
2831 }
2832 
2833 static inline bool btrfs_root_dead(struct btrfs_root *root)
2834 {
2835 	return (root->root_item.flags & cpu_to_le64(BTRFS_ROOT_SUBVOL_DEAD)) != 0;
2836 }
2837 
2838 /* struct btrfs_root_backup */
2839 BTRFS_SETGET_STACK_FUNCS(backup_tree_root, struct btrfs_root_backup,
2840 		   tree_root, 64);
2841 BTRFS_SETGET_STACK_FUNCS(backup_tree_root_gen, struct btrfs_root_backup,
2842 		   tree_root_gen, 64);
2843 BTRFS_SETGET_STACK_FUNCS(backup_tree_root_level, struct btrfs_root_backup,
2844 		   tree_root_level, 8);
2845 
2846 BTRFS_SETGET_STACK_FUNCS(backup_chunk_root, struct btrfs_root_backup,
2847 		   chunk_root, 64);
2848 BTRFS_SETGET_STACK_FUNCS(backup_chunk_root_gen, struct btrfs_root_backup,
2849 		   chunk_root_gen, 64);
2850 BTRFS_SETGET_STACK_FUNCS(backup_chunk_root_level, struct btrfs_root_backup,
2851 		   chunk_root_level, 8);
2852 
2853 BTRFS_SETGET_STACK_FUNCS(backup_extent_root, struct btrfs_root_backup,
2854 		   extent_root, 64);
2855 BTRFS_SETGET_STACK_FUNCS(backup_extent_root_gen, struct btrfs_root_backup,
2856 		   extent_root_gen, 64);
2857 BTRFS_SETGET_STACK_FUNCS(backup_extent_root_level, struct btrfs_root_backup,
2858 		   extent_root_level, 8);
2859 
2860 BTRFS_SETGET_STACK_FUNCS(backup_fs_root, struct btrfs_root_backup,
2861 		   fs_root, 64);
2862 BTRFS_SETGET_STACK_FUNCS(backup_fs_root_gen, struct btrfs_root_backup,
2863 		   fs_root_gen, 64);
2864 BTRFS_SETGET_STACK_FUNCS(backup_fs_root_level, struct btrfs_root_backup,
2865 		   fs_root_level, 8);
2866 
2867 BTRFS_SETGET_STACK_FUNCS(backup_dev_root, struct btrfs_root_backup,
2868 		   dev_root, 64);
2869 BTRFS_SETGET_STACK_FUNCS(backup_dev_root_gen, struct btrfs_root_backup,
2870 		   dev_root_gen, 64);
2871 BTRFS_SETGET_STACK_FUNCS(backup_dev_root_level, struct btrfs_root_backup,
2872 		   dev_root_level, 8);
2873 
2874 BTRFS_SETGET_STACK_FUNCS(backup_csum_root, struct btrfs_root_backup,
2875 		   csum_root, 64);
2876 BTRFS_SETGET_STACK_FUNCS(backup_csum_root_gen, struct btrfs_root_backup,
2877 		   csum_root_gen, 64);
2878 BTRFS_SETGET_STACK_FUNCS(backup_csum_root_level, struct btrfs_root_backup,
2879 		   csum_root_level, 8);
2880 BTRFS_SETGET_STACK_FUNCS(backup_total_bytes, struct btrfs_root_backup,
2881 		   total_bytes, 64);
2882 BTRFS_SETGET_STACK_FUNCS(backup_bytes_used, struct btrfs_root_backup,
2883 		   bytes_used, 64);
2884 BTRFS_SETGET_STACK_FUNCS(backup_num_devices, struct btrfs_root_backup,
2885 		   num_devices, 64);
2886 
2887 /* struct btrfs_balance_item */
2888 BTRFS_SETGET_FUNCS(balance_flags, struct btrfs_balance_item, flags, 64);
2889 
2890 static inline void btrfs_balance_data(struct extent_buffer *eb,
2891 				      struct btrfs_balance_item *bi,
2892 				      struct btrfs_disk_balance_args *ba)
2893 {
2894 	read_eb_member(eb, bi, struct btrfs_balance_item, data, ba);
2895 }
2896 
2897 static inline void btrfs_set_balance_data(struct extent_buffer *eb,
2898 					  struct btrfs_balance_item *bi,
2899 					  struct btrfs_disk_balance_args *ba)
2900 {
2901 	write_eb_member(eb, bi, struct btrfs_balance_item, data, ba);
2902 }
2903 
2904 static inline void btrfs_balance_meta(struct extent_buffer *eb,
2905 				      struct btrfs_balance_item *bi,
2906 				      struct btrfs_disk_balance_args *ba)
2907 {
2908 	read_eb_member(eb, bi, struct btrfs_balance_item, meta, ba);
2909 }
2910 
2911 static inline void btrfs_set_balance_meta(struct extent_buffer *eb,
2912 					  struct btrfs_balance_item *bi,
2913 					  struct btrfs_disk_balance_args *ba)
2914 {
2915 	write_eb_member(eb, bi, struct btrfs_balance_item, meta, ba);
2916 }
2917 
2918 static inline void btrfs_balance_sys(struct extent_buffer *eb,
2919 				     struct btrfs_balance_item *bi,
2920 				     struct btrfs_disk_balance_args *ba)
2921 {
2922 	read_eb_member(eb, bi, struct btrfs_balance_item, sys, ba);
2923 }
2924 
2925 static inline void btrfs_set_balance_sys(struct extent_buffer *eb,
2926 					 struct btrfs_balance_item *bi,
2927 					 struct btrfs_disk_balance_args *ba)
2928 {
2929 	write_eb_member(eb, bi, struct btrfs_balance_item, sys, ba);
2930 }
2931 
2932 static inline void
2933 btrfs_disk_balance_args_to_cpu(struct btrfs_balance_args *cpu,
2934 			       struct btrfs_disk_balance_args *disk)
2935 {
2936 	memset(cpu, 0, sizeof(*cpu));
2937 
2938 	cpu->profiles = le64_to_cpu(disk->profiles);
2939 	cpu->usage = le64_to_cpu(disk->usage);
2940 	cpu->devid = le64_to_cpu(disk->devid);
2941 	cpu->pstart = le64_to_cpu(disk->pstart);
2942 	cpu->pend = le64_to_cpu(disk->pend);
2943 	cpu->vstart = le64_to_cpu(disk->vstart);
2944 	cpu->vend = le64_to_cpu(disk->vend);
2945 	cpu->target = le64_to_cpu(disk->target);
2946 	cpu->flags = le64_to_cpu(disk->flags);
2947 	cpu->limit = le64_to_cpu(disk->limit);
2948 }
2949 
2950 static inline void
2951 btrfs_cpu_balance_args_to_disk(struct btrfs_disk_balance_args *disk,
2952 			       struct btrfs_balance_args *cpu)
2953 {
2954 	memset(disk, 0, sizeof(*disk));
2955 
2956 	disk->profiles = cpu_to_le64(cpu->profiles);
2957 	disk->usage = cpu_to_le64(cpu->usage);
2958 	disk->devid = cpu_to_le64(cpu->devid);
2959 	disk->pstart = cpu_to_le64(cpu->pstart);
2960 	disk->pend = cpu_to_le64(cpu->pend);
2961 	disk->vstart = cpu_to_le64(cpu->vstart);
2962 	disk->vend = cpu_to_le64(cpu->vend);
2963 	disk->target = cpu_to_le64(cpu->target);
2964 	disk->flags = cpu_to_le64(cpu->flags);
2965 	disk->limit = cpu_to_le64(cpu->limit);
2966 }
2967 
2968 /* struct btrfs_super_block */
2969 BTRFS_SETGET_STACK_FUNCS(super_bytenr, struct btrfs_super_block, bytenr, 64);
2970 BTRFS_SETGET_STACK_FUNCS(super_flags, struct btrfs_super_block, flags, 64);
2971 BTRFS_SETGET_STACK_FUNCS(super_generation, struct btrfs_super_block,
2972 			 generation, 64);
2973 BTRFS_SETGET_STACK_FUNCS(super_root, struct btrfs_super_block, root, 64);
2974 BTRFS_SETGET_STACK_FUNCS(super_sys_array_size,
2975 			 struct btrfs_super_block, sys_chunk_array_size, 32);
2976 BTRFS_SETGET_STACK_FUNCS(super_chunk_root_generation,
2977 			 struct btrfs_super_block, chunk_root_generation, 64);
2978 BTRFS_SETGET_STACK_FUNCS(super_root_level, struct btrfs_super_block,
2979 			 root_level, 8);
2980 BTRFS_SETGET_STACK_FUNCS(super_chunk_root, struct btrfs_super_block,
2981 			 chunk_root, 64);
2982 BTRFS_SETGET_STACK_FUNCS(super_chunk_root_level, struct btrfs_super_block,
2983 			 chunk_root_level, 8);
2984 BTRFS_SETGET_STACK_FUNCS(super_log_root, struct btrfs_super_block,
2985 			 log_root, 64);
2986 BTRFS_SETGET_STACK_FUNCS(super_log_root_transid, struct btrfs_super_block,
2987 			 log_root_transid, 64);
2988 BTRFS_SETGET_STACK_FUNCS(super_log_root_level, struct btrfs_super_block,
2989 			 log_root_level, 8);
2990 BTRFS_SETGET_STACK_FUNCS(super_total_bytes, struct btrfs_super_block,
2991 			 total_bytes, 64);
2992 BTRFS_SETGET_STACK_FUNCS(super_bytes_used, struct btrfs_super_block,
2993 			 bytes_used, 64);
2994 BTRFS_SETGET_STACK_FUNCS(super_sectorsize, struct btrfs_super_block,
2995 			 sectorsize, 32);
2996 BTRFS_SETGET_STACK_FUNCS(super_nodesize, struct btrfs_super_block,
2997 			 nodesize, 32);
2998 BTRFS_SETGET_STACK_FUNCS(super_leafsize, struct btrfs_super_block,
2999 			 leafsize, 32);
3000 BTRFS_SETGET_STACK_FUNCS(super_stripesize, struct btrfs_super_block,
3001 			 stripesize, 32);
3002 BTRFS_SETGET_STACK_FUNCS(super_root_dir, struct btrfs_super_block,
3003 			 root_dir_objectid, 64);
3004 BTRFS_SETGET_STACK_FUNCS(super_num_devices, struct btrfs_super_block,
3005 			 num_devices, 64);
3006 BTRFS_SETGET_STACK_FUNCS(super_compat_flags, struct btrfs_super_block,
3007 			 compat_flags, 64);
3008 BTRFS_SETGET_STACK_FUNCS(super_compat_ro_flags, struct btrfs_super_block,
3009 			 compat_ro_flags, 64);
3010 BTRFS_SETGET_STACK_FUNCS(super_incompat_flags, struct btrfs_super_block,
3011 			 incompat_flags, 64);
3012 BTRFS_SETGET_STACK_FUNCS(super_csum_type, struct btrfs_super_block,
3013 			 csum_type, 16);
3014 BTRFS_SETGET_STACK_FUNCS(super_cache_generation, struct btrfs_super_block,
3015 			 cache_generation, 64);
3016 BTRFS_SETGET_STACK_FUNCS(super_magic, struct btrfs_super_block, magic, 64);
3017 BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block,
3018 			 uuid_tree_generation, 64);
3019 
3020 static inline int btrfs_super_csum_size(struct btrfs_super_block *s)
3021 {
3022 	u16 t = btrfs_super_csum_type(s);
3023 	/*
3024 	 * csum type is validated at mount time
3025 	 */
3026 	return btrfs_csum_sizes[t];
3027 }
3028 
3029 static inline unsigned long btrfs_leaf_data(struct extent_buffer *l)
3030 {
3031 	return offsetof(struct btrfs_leaf, items);
3032 }
3033 
3034 /* struct btrfs_file_extent_item */
3035 BTRFS_SETGET_FUNCS(file_extent_type, struct btrfs_file_extent_item, type, 8);
3036 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_disk_bytenr,
3037 			 struct btrfs_file_extent_item, disk_bytenr, 64);
3038 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_offset,
3039 			 struct btrfs_file_extent_item, offset, 64);
3040 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_generation,
3041 			 struct btrfs_file_extent_item, generation, 64);
3042 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_num_bytes,
3043 			 struct btrfs_file_extent_item, num_bytes, 64);
3044 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_disk_num_bytes,
3045 			 struct btrfs_file_extent_item, disk_num_bytes, 64);
3046 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_compression,
3047 			 struct btrfs_file_extent_item, compression, 8);
3048 
3049 static inline unsigned long
3050 btrfs_file_extent_inline_start(struct btrfs_file_extent_item *e)
3051 {
3052 	unsigned long offset = (unsigned long)e;
3053 	offset += offsetof(struct btrfs_file_extent_item, disk_bytenr);
3054 	return offset;
3055 }
3056 
3057 static inline u32 btrfs_file_extent_calc_inline_size(u32 datasize)
3058 {
3059 	return offsetof(struct btrfs_file_extent_item, disk_bytenr) + datasize;
3060 }
3061 
3062 BTRFS_SETGET_FUNCS(file_extent_disk_bytenr, struct btrfs_file_extent_item,
3063 		   disk_bytenr, 64);
3064 BTRFS_SETGET_FUNCS(file_extent_generation, struct btrfs_file_extent_item,
3065 		   generation, 64);
3066 BTRFS_SETGET_FUNCS(file_extent_disk_num_bytes, struct btrfs_file_extent_item,
3067 		   disk_num_bytes, 64);
3068 BTRFS_SETGET_FUNCS(file_extent_offset, struct btrfs_file_extent_item,
3069 		  offset, 64);
3070 BTRFS_SETGET_FUNCS(file_extent_num_bytes, struct btrfs_file_extent_item,
3071 		   num_bytes, 64);
3072 BTRFS_SETGET_FUNCS(file_extent_ram_bytes, struct btrfs_file_extent_item,
3073 		   ram_bytes, 64);
3074 BTRFS_SETGET_FUNCS(file_extent_compression, struct btrfs_file_extent_item,
3075 		   compression, 8);
3076 BTRFS_SETGET_FUNCS(file_extent_encryption, struct btrfs_file_extent_item,
3077 		   encryption, 8);
3078 BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item,
3079 		   other_encoding, 16);
3080 
3081 /*
3082  * this returns the number of bytes used by the item on disk, minus the
3083  * size of any extent headers.  If a file is compressed on disk, this is
3084  * the compressed size
3085  */
3086 static inline u32 btrfs_file_extent_inline_item_len(struct extent_buffer *eb,
3087 						    struct btrfs_item *e)
3088 {
3089 	unsigned long offset;
3090 	offset = offsetof(struct btrfs_file_extent_item, disk_bytenr);
3091 	return btrfs_item_size(eb, e) - offset;
3092 }
3093 
3094 /* this returns the number of file bytes represented by the inline item.
3095  * If an item is compressed, this is the uncompressed size
3096  */
3097 static inline u32 btrfs_file_extent_inline_len(struct extent_buffer *eb,
3098 					       int slot,
3099 					       struct btrfs_file_extent_item *fi)
3100 {
3101 	struct btrfs_map_token token;
3102 
3103 	btrfs_init_map_token(&token);
3104 	/*
3105 	 * return the space used on disk if this item isn't
3106 	 * compressed or encoded
3107 	 */
3108 	if (btrfs_token_file_extent_compression(eb, fi, &token) == 0 &&
3109 	    btrfs_token_file_extent_encryption(eb, fi, &token) == 0 &&
3110 	    btrfs_token_file_extent_other_encoding(eb, fi, &token) == 0) {
3111 		return btrfs_file_extent_inline_item_len(eb,
3112 							 btrfs_item_nr(slot));
3113 	}
3114 
3115 	/* otherwise use the ram bytes field */
3116 	return btrfs_token_file_extent_ram_bytes(eb, fi, &token);
3117 }
3118 
3119 
3120 /* btrfs_dev_stats_item */
3121 static inline u64 btrfs_dev_stats_value(struct extent_buffer *eb,
3122 					struct btrfs_dev_stats_item *ptr,
3123 					int index)
3124 {
3125 	u64 val;
3126 
3127 	read_extent_buffer(eb, &val,
3128 			   offsetof(struct btrfs_dev_stats_item, values) +
3129 			    ((unsigned long)ptr) + (index * sizeof(u64)),
3130 			   sizeof(val));
3131 	return val;
3132 }
3133 
3134 static inline void btrfs_set_dev_stats_value(struct extent_buffer *eb,
3135 					     struct btrfs_dev_stats_item *ptr,
3136 					     int index, u64 val)
3137 {
3138 	write_extent_buffer(eb, &val,
3139 			    offsetof(struct btrfs_dev_stats_item, values) +
3140 			     ((unsigned long)ptr) + (index * sizeof(u64)),
3141 			    sizeof(val));
3142 }
3143 
3144 /* btrfs_qgroup_status_item */
3145 BTRFS_SETGET_FUNCS(qgroup_status_generation, struct btrfs_qgroup_status_item,
3146 		   generation, 64);
3147 BTRFS_SETGET_FUNCS(qgroup_status_version, struct btrfs_qgroup_status_item,
3148 		   version, 64);
3149 BTRFS_SETGET_FUNCS(qgroup_status_flags, struct btrfs_qgroup_status_item,
3150 		   flags, 64);
3151 BTRFS_SETGET_FUNCS(qgroup_status_rescan, struct btrfs_qgroup_status_item,
3152 		   rescan, 64);
3153 
3154 /* btrfs_qgroup_info_item */
3155 BTRFS_SETGET_FUNCS(qgroup_info_generation, struct btrfs_qgroup_info_item,
3156 		   generation, 64);
3157 BTRFS_SETGET_FUNCS(qgroup_info_rfer, struct btrfs_qgroup_info_item, rfer, 64);
3158 BTRFS_SETGET_FUNCS(qgroup_info_rfer_cmpr, struct btrfs_qgroup_info_item,
3159 		   rfer_cmpr, 64);
3160 BTRFS_SETGET_FUNCS(qgroup_info_excl, struct btrfs_qgroup_info_item, excl, 64);
3161 BTRFS_SETGET_FUNCS(qgroup_info_excl_cmpr, struct btrfs_qgroup_info_item,
3162 		   excl_cmpr, 64);
3163 
3164 BTRFS_SETGET_STACK_FUNCS(stack_qgroup_info_generation,
3165 			 struct btrfs_qgroup_info_item, generation, 64);
3166 BTRFS_SETGET_STACK_FUNCS(stack_qgroup_info_rfer, struct btrfs_qgroup_info_item,
3167 			 rfer, 64);
3168 BTRFS_SETGET_STACK_FUNCS(stack_qgroup_info_rfer_cmpr,
3169 			 struct btrfs_qgroup_info_item, rfer_cmpr, 64);
3170 BTRFS_SETGET_STACK_FUNCS(stack_qgroup_info_excl, struct btrfs_qgroup_info_item,
3171 			 excl, 64);
3172 BTRFS_SETGET_STACK_FUNCS(stack_qgroup_info_excl_cmpr,
3173 			 struct btrfs_qgroup_info_item, excl_cmpr, 64);
3174 
3175 /* btrfs_qgroup_limit_item */
3176 BTRFS_SETGET_FUNCS(qgroup_limit_flags, struct btrfs_qgroup_limit_item,
3177 		   flags, 64);
3178 BTRFS_SETGET_FUNCS(qgroup_limit_max_rfer, struct btrfs_qgroup_limit_item,
3179 		   max_rfer, 64);
3180 BTRFS_SETGET_FUNCS(qgroup_limit_max_excl, struct btrfs_qgroup_limit_item,
3181 		   max_excl, 64);
3182 BTRFS_SETGET_FUNCS(qgroup_limit_rsv_rfer, struct btrfs_qgroup_limit_item,
3183 		   rsv_rfer, 64);
3184 BTRFS_SETGET_FUNCS(qgroup_limit_rsv_excl, struct btrfs_qgroup_limit_item,
3185 		   rsv_excl, 64);
3186 
3187 /* btrfs_dev_replace_item */
3188 BTRFS_SETGET_FUNCS(dev_replace_src_devid,
3189 		   struct btrfs_dev_replace_item, src_devid, 64);
3190 BTRFS_SETGET_FUNCS(dev_replace_cont_reading_from_srcdev_mode,
3191 		   struct btrfs_dev_replace_item, cont_reading_from_srcdev_mode,
3192 		   64);
3193 BTRFS_SETGET_FUNCS(dev_replace_replace_state, struct btrfs_dev_replace_item,
3194 		   replace_state, 64);
3195 BTRFS_SETGET_FUNCS(dev_replace_time_started, struct btrfs_dev_replace_item,
3196 		   time_started, 64);
3197 BTRFS_SETGET_FUNCS(dev_replace_time_stopped, struct btrfs_dev_replace_item,
3198 		   time_stopped, 64);
3199 BTRFS_SETGET_FUNCS(dev_replace_num_write_errors, struct btrfs_dev_replace_item,
3200 		   num_write_errors, 64);
3201 BTRFS_SETGET_FUNCS(dev_replace_num_uncorrectable_read_errors,
3202 		   struct btrfs_dev_replace_item, num_uncorrectable_read_errors,
3203 		   64);
3204 BTRFS_SETGET_FUNCS(dev_replace_cursor_left, struct btrfs_dev_replace_item,
3205 		   cursor_left, 64);
3206 BTRFS_SETGET_FUNCS(dev_replace_cursor_right, struct btrfs_dev_replace_item,
3207 		   cursor_right, 64);
3208 
3209 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_src_devid,
3210 			 struct btrfs_dev_replace_item, src_devid, 64);
3211 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_cont_reading_from_srcdev_mode,
3212 			 struct btrfs_dev_replace_item,
3213 			 cont_reading_from_srcdev_mode, 64);
3214 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_replace_state,
3215 			 struct btrfs_dev_replace_item, replace_state, 64);
3216 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_time_started,
3217 			 struct btrfs_dev_replace_item, time_started, 64);
3218 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_time_stopped,
3219 			 struct btrfs_dev_replace_item, time_stopped, 64);
3220 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_num_write_errors,
3221 			 struct btrfs_dev_replace_item, num_write_errors, 64);
3222 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_num_uncorrectable_read_errors,
3223 			 struct btrfs_dev_replace_item,
3224 			 num_uncorrectable_read_errors, 64);
3225 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_cursor_left,
3226 			 struct btrfs_dev_replace_item, cursor_left, 64);
3227 BTRFS_SETGET_STACK_FUNCS(stack_dev_replace_cursor_right,
3228 			 struct btrfs_dev_replace_item, cursor_right, 64);
3229 
3230 static inline struct btrfs_fs_info *btrfs_sb(struct super_block *sb)
3231 {
3232 	return sb->s_fs_info;
3233 }
3234 
3235 static inline u32 btrfs_level_size(struct btrfs_root *root, int level)
3236 {
3237 	if (level == 0)
3238 		return root->leafsize;
3239 	return root->nodesize;
3240 }
3241 
3242 /* helper function to cast into the data area of the leaf. */
3243 #define btrfs_item_ptr(leaf, slot, type) \
3244 	((type *)(btrfs_leaf_data(leaf) + \
3245 	btrfs_item_offset_nr(leaf, slot)))
3246 
3247 #define btrfs_item_ptr_offset(leaf, slot) \
3248 	((unsigned long)(btrfs_leaf_data(leaf) + \
3249 	btrfs_item_offset_nr(leaf, slot)))
3250 
3251 static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
3252 {
3253 	return ((space_info->flags & BTRFS_BLOCK_GROUP_METADATA) &&
3254 		(space_info->flags & BTRFS_BLOCK_GROUP_DATA));
3255 }
3256 
3257 static inline gfp_t btrfs_alloc_write_mask(struct address_space *mapping)
3258 {
3259 	return mapping_gfp_mask(mapping) & ~__GFP_FS;
3260 }
3261 
3262 /* extent-tree.c */
3263 static inline u64 btrfs_calc_trans_metadata_size(struct btrfs_root *root,
3264 						 unsigned num_items)
3265 {
3266 	return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3267 		2 * num_items;
3268 }
3269 
3270 /*
3271  * Doing a truncate won't result in new nodes or leaves, just what we need for
3272  * COW.
3273  */
3274 static inline u64 btrfs_calc_trunc_metadata_size(struct btrfs_root *root,
3275 						 unsigned num_items)
3276 {
3277 	return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
3278 		num_items;
3279 }
3280 
3281 int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans,
3282 				       struct btrfs_root *root);
3283 int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
3284 				       struct btrfs_root *root);
3285 void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
3286 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
3287 			   struct btrfs_root *root, unsigned long count);
3288 int btrfs_async_run_delayed_refs(struct btrfs_root *root,
3289 				 unsigned long count, int wait);
3290 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len);
3291 int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
3292 			     struct btrfs_root *root, u64 bytenr,
3293 			     u64 offset, int metadata, u64 *refs, u64 *flags);
3294 int btrfs_pin_extent(struct btrfs_root *root,
3295 		     u64 bytenr, u64 num, int reserved);
3296 int btrfs_pin_extent_for_log_replay(struct btrfs_root *root,
3297 				    u64 bytenr, u64 num_bytes);
3298 int btrfs_exclude_logged_extents(struct btrfs_root *root,
3299 				 struct extent_buffer *eb);
3300 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
3301 			  struct btrfs_root *root,
3302 			  u64 objectid, u64 offset, u64 bytenr);
3303 struct btrfs_block_group_cache *btrfs_lookup_block_group(
3304 						 struct btrfs_fs_info *info,
3305 						 u64 bytenr);
3306 void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
3307 int get_block_group_index(struct btrfs_block_group_cache *cache);
3308 struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
3309 					struct btrfs_root *root, u32 blocksize,
3310 					u64 parent, u64 root_objectid,
3311 					struct btrfs_disk_key *key, int level,
3312 					u64 hint, u64 empty_size);
3313 void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
3314 			   struct btrfs_root *root,
3315 			   struct extent_buffer *buf,
3316 			   u64 parent, int last_ref);
3317 int btrfs_alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
3318 				     struct btrfs_root *root,
3319 				     u64 root_objectid, u64 owner,
3320 				     u64 offset, struct btrfs_key *ins);
3321 int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
3322 				   struct btrfs_root *root,
3323 				   u64 root_objectid, u64 owner, u64 offset,
3324 				   struct btrfs_key *ins);
3325 int btrfs_reserve_extent(struct btrfs_root *root, u64 num_bytes,
3326 			 u64 min_alloc_size, u64 empty_size, u64 hint_byte,
3327 			 struct btrfs_key *ins, int is_data, int delalloc);
3328 int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3329 		  struct extent_buffer *buf, int full_backref);
3330 int btrfs_dec_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3331 		  struct extent_buffer *buf, int full_backref);
3332 int btrfs_set_disk_extent_flags(struct btrfs_trans_handle *trans,
3333 				struct btrfs_root *root,
3334 				u64 bytenr, u64 num_bytes, u64 flags,
3335 				int level, int is_data);
3336 int btrfs_free_extent(struct btrfs_trans_handle *trans,
3337 		      struct btrfs_root *root,
3338 		      u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
3339 		      u64 owner, u64 offset, int no_quota);
3340 
3341 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len,
3342 			       int delalloc);
3343 int btrfs_free_and_pin_reserved_extent(struct btrfs_root *root,
3344 				       u64 start, u64 len);
3345 void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
3346 				 struct btrfs_root *root);
3347 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
3348 			       struct btrfs_root *root);
3349 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
3350 			 struct btrfs_root *root,
3351 			 u64 bytenr, u64 num_bytes, u64 parent,
3352 			 u64 root_objectid, u64 owner, u64 offset, int no_quota);
3353 
3354 int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
3355 				    struct btrfs_root *root);
3356 int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr);
3357 int btrfs_free_block_groups(struct btrfs_fs_info *info);
3358 int btrfs_read_block_groups(struct btrfs_root *root);
3359 int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr);
3360 int btrfs_make_block_group(struct btrfs_trans_handle *trans,
3361 			   struct btrfs_root *root, u64 bytes_used,
3362 			   u64 type, u64 chunk_objectid, u64 chunk_offset,
3363 			   u64 size);
3364 int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
3365 			     struct btrfs_root *root, u64 group_start);
3366 void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
3367 				       struct btrfs_root *root);
3368 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data);
3369 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
3370 
3371 enum btrfs_reserve_flush_enum {
3372 	/* If we are in the transaction, we can't flush anything.*/
3373 	BTRFS_RESERVE_NO_FLUSH,
3374 	/*
3375 	 * Flushing delalloc may cause deadlock somewhere, in this
3376 	 * case, use FLUSH LIMIT
3377 	 */
3378 	BTRFS_RESERVE_FLUSH_LIMIT,
3379 	BTRFS_RESERVE_FLUSH_ALL,
3380 };
3381 
3382 int btrfs_check_data_free_space(struct inode *inode, u64 bytes);
3383 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes);
3384 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
3385 				struct btrfs_root *root);
3386 int btrfs_orphan_reserve_metadata(struct btrfs_trans_handle *trans,
3387 				  struct inode *inode);
3388 void btrfs_orphan_release_metadata(struct inode *inode);
3389 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
3390 				     struct btrfs_block_rsv *rsv,
3391 				     int nitems,
3392 				     u64 *qgroup_reserved, bool use_global_rsv);
3393 void btrfs_subvolume_release_metadata(struct btrfs_root *root,
3394 				      struct btrfs_block_rsv *rsv,
3395 				      u64 qgroup_reserved);
3396 int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes);
3397 void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes);
3398 int btrfs_delalloc_reserve_space(struct inode *inode, u64 num_bytes);
3399 void btrfs_delalloc_release_space(struct inode *inode, u64 num_bytes);
3400 void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type);
3401 struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root,
3402 					      unsigned short type);
3403 void btrfs_free_block_rsv(struct btrfs_root *root,
3404 			  struct btrfs_block_rsv *rsv);
3405 int btrfs_block_rsv_add(struct btrfs_root *root,
3406 			struct btrfs_block_rsv *block_rsv, u64 num_bytes,
3407 			enum btrfs_reserve_flush_enum flush);
3408 int btrfs_block_rsv_check(struct btrfs_root *root,
3409 			  struct btrfs_block_rsv *block_rsv, int min_factor);
3410 int btrfs_block_rsv_refill(struct btrfs_root *root,
3411 			   struct btrfs_block_rsv *block_rsv, u64 min_reserved,
3412 			   enum btrfs_reserve_flush_enum flush);
3413 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
3414 			    struct btrfs_block_rsv *dst_rsv,
3415 			    u64 num_bytes);
3416 int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
3417 			     struct btrfs_block_rsv *dest, u64 num_bytes,
3418 			     int min_factor);
3419 void btrfs_block_rsv_release(struct btrfs_root *root,
3420 			     struct btrfs_block_rsv *block_rsv,
3421 			     u64 num_bytes);
3422 int btrfs_set_block_group_ro(struct btrfs_root *root,
3423 			     struct btrfs_block_group_cache *cache);
3424 void btrfs_set_block_group_rw(struct btrfs_root *root,
3425 			      struct btrfs_block_group_cache *cache);
3426 void btrfs_put_block_group_cache(struct btrfs_fs_info *info);
3427 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
3428 int btrfs_error_unpin_extent_range(struct btrfs_root *root,
3429 				   u64 start, u64 end);
3430 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
3431 			       u64 num_bytes, u64 *actual_bytes);
3432 int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
3433 			    struct btrfs_root *root, u64 type);
3434 int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range);
3435 
3436 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
3437 int btrfs_delayed_refs_qgroup_accounting(struct btrfs_trans_handle *trans,
3438 					 struct btrfs_fs_info *fs_info);
3439 int __get_raid_index(u64 flags);
3440 int btrfs_start_nocow_write(struct btrfs_root *root);
3441 void btrfs_end_nocow_write(struct btrfs_root *root);
3442 /* ctree.c */
3443 int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key,
3444 		     int level, int *slot);
3445 int btrfs_comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2);
3446 int btrfs_previous_item(struct btrfs_root *root,
3447 			struct btrfs_path *path, u64 min_objectid,
3448 			int type);
3449 int btrfs_previous_extent_item(struct btrfs_root *root,
3450 			struct btrfs_path *path, u64 min_objectid);
3451 void btrfs_set_item_key_safe(struct btrfs_root *root, struct btrfs_path *path,
3452 			     struct btrfs_key *new_key);
3453 struct extent_buffer *btrfs_root_node(struct btrfs_root *root);
3454 struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root);
3455 int btrfs_find_next_key(struct btrfs_root *root, struct btrfs_path *path,
3456 			struct btrfs_key *key, int lowest_level,
3457 			u64 min_trans);
3458 int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
3459 			 struct btrfs_path *path,
3460 			 u64 min_trans);
3461 enum btrfs_compare_tree_result {
3462 	BTRFS_COMPARE_TREE_NEW,
3463 	BTRFS_COMPARE_TREE_DELETED,
3464 	BTRFS_COMPARE_TREE_CHANGED,
3465 	BTRFS_COMPARE_TREE_SAME,
3466 };
3467 typedef int (*btrfs_changed_cb_t)(struct btrfs_root *left_root,
3468 				  struct btrfs_root *right_root,
3469 				  struct btrfs_path *left_path,
3470 				  struct btrfs_path *right_path,
3471 				  struct btrfs_key *key,
3472 				  enum btrfs_compare_tree_result result,
3473 				  void *ctx);
3474 int btrfs_compare_trees(struct btrfs_root *left_root,
3475 			struct btrfs_root *right_root,
3476 			btrfs_changed_cb_t cb, void *ctx);
3477 int btrfs_cow_block(struct btrfs_trans_handle *trans,
3478 		    struct btrfs_root *root, struct extent_buffer *buf,
3479 		    struct extent_buffer *parent, int parent_slot,
3480 		    struct extent_buffer **cow_ret);
3481 int btrfs_copy_root(struct btrfs_trans_handle *trans,
3482 		      struct btrfs_root *root,
3483 		      struct extent_buffer *buf,
3484 		      struct extent_buffer **cow_ret, u64 new_root_objectid);
3485 int btrfs_block_can_be_shared(struct btrfs_root *root,
3486 			      struct extent_buffer *buf);
3487 void btrfs_extend_item(struct btrfs_root *root, struct btrfs_path *path,
3488 		       u32 data_size);
3489 void btrfs_truncate_item(struct btrfs_root *root, struct btrfs_path *path,
3490 			 u32 new_size, int from_end);
3491 int btrfs_split_item(struct btrfs_trans_handle *trans,
3492 		     struct btrfs_root *root,
3493 		     struct btrfs_path *path,
3494 		     struct btrfs_key *new_key,
3495 		     unsigned long split_offset);
3496 int btrfs_duplicate_item(struct btrfs_trans_handle *trans,
3497 			 struct btrfs_root *root,
3498 			 struct btrfs_path *path,
3499 			 struct btrfs_key *new_key);
3500 int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *path,
3501 		u64 inum, u64 ioff, u8 key_type, struct btrfs_key *found_key);
3502 int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
3503 		      *root, struct btrfs_key *key, struct btrfs_path *p, int
3504 		      ins_len, int cow);
3505 int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
3506 			  struct btrfs_path *p, u64 time_seq);
3507 int btrfs_search_slot_for_read(struct btrfs_root *root,
3508 			       struct btrfs_key *key, struct btrfs_path *p,
3509 			       int find_higher, int return_any);
3510 int btrfs_realloc_node(struct btrfs_trans_handle *trans,
3511 		       struct btrfs_root *root, struct extent_buffer *parent,
3512 		       int start_slot, u64 *last_ret,
3513 		       struct btrfs_key *progress);
3514 void btrfs_release_path(struct btrfs_path *p);
3515 struct btrfs_path *btrfs_alloc_path(void);
3516 void btrfs_free_path(struct btrfs_path *p);
3517 void btrfs_set_path_blocking(struct btrfs_path *p);
3518 void btrfs_clear_path_blocking(struct btrfs_path *p,
3519 			       struct extent_buffer *held, int held_rw);
3520 void btrfs_unlock_up_safe(struct btrfs_path *p, int level);
3521 
3522 int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3523 		   struct btrfs_path *path, int slot, int nr);
3524 static inline int btrfs_del_item(struct btrfs_trans_handle *trans,
3525 				 struct btrfs_root *root,
3526 				 struct btrfs_path *path)
3527 {
3528 	return btrfs_del_items(trans, root, path, path->slots[0], 1);
3529 }
3530 
3531 void setup_items_for_insert(struct btrfs_root *root, struct btrfs_path *path,
3532 			    struct btrfs_key *cpu_key, u32 *data_size,
3533 			    u32 total_data, u32 total_size, int nr);
3534 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
3535 		      *root, struct btrfs_key *key, void *data, u32 data_size);
3536 int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
3537 			     struct btrfs_root *root,
3538 			     struct btrfs_path *path,
3539 			     struct btrfs_key *cpu_key, u32 *data_size, int nr);
3540 
3541 static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
3542 					  struct btrfs_root *root,
3543 					  struct btrfs_path *path,
3544 					  struct btrfs_key *key,
3545 					  u32 data_size)
3546 {
3547 	return btrfs_insert_empty_items(trans, root, path, key, &data_size, 1);
3548 }
3549 
3550 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
3551 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
3552 int btrfs_next_old_leaf(struct btrfs_root *root, struct btrfs_path *path,
3553 			u64 time_seq);
3554 static inline int btrfs_next_old_item(struct btrfs_root *root,
3555 				      struct btrfs_path *p, u64 time_seq)
3556 {
3557 	++p->slots[0];
3558 	if (p->slots[0] >= btrfs_header_nritems(p->nodes[0]))
3559 		return btrfs_next_old_leaf(root, p, time_seq);
3560 	return 0;
3561 }
3562 static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p)
3563 {
3564 	return btrfs_next_old_item(root, p, 0);
3565 }
3566 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
3567 int __must_check btrfs_drop_snapshot(struct btrfs_root *root,
3568 				     struct btrfs_block_rsv *block_rsv,
3569 				     int update_ref, int for_reloc);
3570 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
3571 			struct btrfs_root *root,
3572 			struct extent_buffer *node,
3573 			struct extent_buffer *parent);
3574 static inline int btrfs_fs_closing(struct btrfs_fs_info *fs_info)
3575 {
3576 	/*
3577 	 * Get synced with close_ctree()
3578 	 */
3579 	smp_mb();
3580 	return fs_info->closing;
3581 }
3582 
3583 /*
3584  * If we remount the fs to be R/O or umount the fs, the cleaner needn't do
3585  * anything except sleeping. This function is used to check the status of
3586  * the fs.
3587  */
3588 static inline int btrfs_need_cleaner_sleep(struct btrfs_root *root)
3589 {
3590 	return (root->fs_info->sb->s_flags & MS_RDONLY ||
3591 		btrfs_fs_closing(root->fs_info));
3592 }
3593 
3594 static inline void free_fs_info(struct btrfs_fs_info *fs_info)
3595 {
3596 	kfree(fs_info->balance_ctl);
3597 	kfree(fs_info->delayed_root);
3598 	kfree(fs_info->extent_root);
3599 	kfree(fs_info->tree_root);
3600 	kfree(fs_info->chunk_root);
3601 	kfree(fs_info->dev_root);
3602 	kfree(fs_info->csum_root);
3603 	kfree(fs_info->quota_root);
3604 	kfree(fs_info->uuid_root);
3605 	kfree(fs_info->super_copy);
3606 	kfree(fs_info->super_for_commit);
3607 	kfree(fs_info);
3608 }
3609 
3610 /* tree mod log functions from ctree.c */
3611 u64 btrfs_get_tree_mod_seq(struct btrfs_fs_info *fs_info,
3612 			   struct seq_list *elem);
3613 void btrfs_put_tree_mod_seq(struct btrfs_fs_info *fs_info,
3614 			    struct seq_list *elem);
3615 int btrfs_old_root_level(struct btrfs_root *root, u64 time_seq);
3616 
3617 /* root-item.c */
3618 int btrfs_find_root_ref(struct btrfs_root *tree_root,
3619 			struct btrfs_path *path,
3620 			u64 root_id, u64 ref_id);
3621 int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
3622 		       struct btrfs_root *tree_root,
3623 		       u64 root_id, u64 ref_id, u64 dirid, u64 sequence,
3624 		       const char *name, int name_len);
3625 int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
3626 		       struct btrfs_root *tree_root,
3627 		       u64 root_id, u64 ref_id, u64 dirid, u64 *sequence,
3628 		       const char *name, int name_len);
3629 int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3630 		   struct btrfs_key *key);
3631 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
3632 		      *root, struct btrfs_key *key, struct btrfs_root_item
3633 		      *item);
3634 int __must_check btrfs_update_root(struct btrfs_trans_handle *trans,
3635 				   struct btrfs_root *root,
3636 				   struct btrfs_key *key,
3637 				   struct btrfs_root_item *item);
3638 int btrfs_find_root(struct btrfs_root *root, struct btrfs_key *search_key,
3639 		    struct btrfs_path *path, struct btrfs_root_item *root_item,
3640 		    struct btrfs_key *root_key);
3641 int btrfs_find_orphan_roots(struct btrfs_root *tree_root);
3642 void btrfs_set_root_node(struct btrfs_root_item *item,
3643 			 struct extent_buffer *node);
3644 void btrfs_check_and_init_root_item(struct btrfs_root_item *item);
3645 void btrfs_update_root_times(struct btrfs_trans_handle *trans,
3646 			     struct btrfs_root *root);
3647 
3648 /* uuid-tree.c */
3649 int btrfs_uuid_tree_add(struct btrfs_trans_handle *trans,
3650 			struct btrfs_root *uuid_root, u8 *uuid, u8 type,
3651 			u64 subid);
3652 int btrfs_uuid_tree_rem(struct btrfs_trans_handle *trans,
3653 			struct btrfs_root *uuid_root, u8 *uuid, u8 type,
3654 			u64 subid);
3655 int btrfs_uuid_tree_iterate(struct btrfs_fs_info *fs_info,
3656 			    int (*check_func)(struct btrfs_fs_info *, u8 *, u8,
3657 					      u64));
3658 
3659 /* dir-item.c */
3660 int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
3661 			  const char *name, int name_len);
3662 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans,
3663 			  struct btrfs_root *root, const char *name,
3664 			  int name_len, struct inode *dir,
3665 			  struct btrfs_key *location, u8 type, u64 index);
3666 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
3667 					     struct btrfs_root *root,
3668 					     struct btrfs_path *path, u64 dir,
3669 					     const char *name, int name_len,
3670 					     int mod);
3671 struct btrfs_dir_item *
3672 btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
3673 			    struct btrfs_root *root,
3674 			    struct btrfs_path *path, u64 dir,
3675 			    u64 objectid, const char *name, int name_len,
3676 			    int mod);
3677 struct btrfs_dir_item *
3678 btrfs_search_dir_index_item(struct btrfs_root *root,
3679 			    struct btrfs_path *path, u64 dirid,
3680 			    const char *name, int name_len);
3681 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
3682 			      struct btrfs_root *root,
3683 			      struct btrfs_path *path,
3684 			      struct btrfs_dir_item *di);
3685 int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
3686 			    struct btrfs_root *root,
3687 			    struct btrfs_path *path, u64 objectid,
3688 			    const char *name, u16 name_len,
3689 			    const void *data, u16 data_len);
3690 struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
3691 					  struct btrfs_root *root,
3692 					  struct btrfs_path *path, u64 dir,
3693 					  const char *name, u16 name_len,
3694 					  int mod);
3695 int verify_dir_item(struct btrfs_root *root,
3696 		    struct extent_buffer *leaf,
3697 		    struct btrfs_dir_item *dir_item);
3698 
3699 /* orphan.c */
3700 int btrfs_insert_orphan_item(struct btrfs_trans_handle *trans,
3701 			     struct btrfs_root *root, u64 offset);
3702 int btrfs_del_orphan_item(struct btrfs_trans_handle *trans,
3703 			  struct btrfs_root *root, u64 offset);
3704 int btrfs_find_orphan_item(struct btrfs_root *root, u64 offset);
3705 
3706 /* inode-item.c */
3707 int btrfs_insert_inode_ref(struct btrfs_trans_handle *trans,
3708 			   struct btrfs_root *root,
3709 			   const char *name, int name_len,
3710 			   u64 inode_objectid, u64 ref_objectid, u64 index);
3711 int btrfs_del_inode_ref(struct btrfs_trans_handle *trans,
3712 			   struct btrfs_root *root,
3713 			   const char *name, int name_len,
3714 			   u64 inode_objectid, u64 ref_objectid, u64 *index);
3715 int btrfs_insert_empty_inode(struct btrfs_trans_handle *trans,
3716 			     struct btrfs_root *root,
3717 			     struct btrfs_path *path, u64 objectid);
3718 int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
3719 		       *root, struct btrfs_path *path,
3720 		       struct btrfs_key *location, int mod);
3721 
3722 struct btrfs_inode_extref *
3723 btrfs_lookup_inode_extref(struct btrfs_trans_handle *trans,
3724 			  struct btrfs_root *root,
3725 			  struct btrfs_path *path,
3726 			  const char *name, int name_len,
3727 			  u64 inode_objectid, u64 ref_objectid, int ins_len,
3728 			  int cow);
3729 
3730 int btrfs_find_name_in_ext_backref(struct btrfs_path *path,
3731 				   u64 ref_objectid, const char *name,
3732 				   int name_len,
3733 				   struct btrfs_inode_extref **extref_ret);
3734 
3735 /* file-item.c */
3736 struct btrfs_dio_private;
3737 int btrfs_del_csums(struct btrfs_trans_handle *trans,
3738 		    struct btrfs_root *root, u64 bytenr, u64 len);
3739 int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode,
3740 			  struct bio *bio, u32 *dst);
3741 int btrfs_lookup_bio_sums_dio(struct btrfs_root *root, struct inode *inode,
3742 			      struct btrfs_dio_private *dip, struct bio *bio,
3743 			      u64 logical_offset);
3744 int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
3745 			     struct btrfs_root *root,
3746 			     u64 objectid, u64 pos,
3747 			     u64 disk_offset, u64 disk_num_bytes,
3748 			     u64 num_bytes, u64 offset, u64 ram_bytes,
3749 			     u8 compression, u8 encryption, u16 other_encoding);
3750 int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
3751 			     struct btrfs_root *root,
3752 			     struct btrfs_path *path, u64 objectid,
3753 			     u64 bytenr, int mod);
3754 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
3755 			   struct btrfs_root *root,
3756 			   struct btrfs_ordered_sum *sums);
3757 int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
3758 		       struct bio *bio, u64 file_start, int contig);
3759 int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
3760 			     struct list_head *list, int search_commit);
3761 void btrfs_extent_item_to_extent_map(struct inode *inode,
3762 				     const struct btrfs_path *path,
3763 				     struct btrfs_file_extent_item *fi,
3764 				     const bool new_inline,
3765 				     struct extent_map *em);
3766 
3767 /* inode.c */
3768 struct btrfs_delalloc_work {
3769 	struct inode *inode;
3770 	int wait;
3771 	int delay_iput;
3772 	struct completion completion;
3773 	struct list_head list;
3774 	struct btrfs_work work;
3775 };
3776 
3777 struct btrfs_delalloc_work *btrfs_alloc_delalloc_work(struct inode *inode,
3778 						    int wait, int delay_iput);
3779 void btrfs_wait_and_free_delalloc_work(struct btrfs_delalloc_work *work);
3780 
3781 struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
3782 					   size_t pg_offset, u64 start, u64 len,
3783 					   int create);
3784 noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
3785 			      u64 *orig_start, u64 *orig_block_len,
3786 			      u64 *ram_bytes);
3787 
3788 /* RHEL and EL kernels have a patch that renames PG_checked to FsMisc */
3789 #if defined(ClearPageFsMisc) && !defined(ClearPageChecked)
3790 #define ClearPageChecked ClearPageFsMisc
3791 #define SetPageChecked SetPageFsMisc
3792 #define PageChecked PageFsMisc
3793 #endif
3794 
3795 /* This forces readahead on a given range of bytes in an inode */
3796 static inline void btrfs_force_ra(struct address_space *mapping,
3797 				  struct file_ra_state *ra, struct file *file,
3798 				  pgoff_t offset, unsigned long req_size)
3799 {
3800 	page_cache_sync_readahead(mapping, ra, file, offset, req_size);
3801 }
3802 
3803 struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry);
3804 int btrfs_set_inode_index(struct inode *dir, u64 *index);
3805 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
3806 		       struct btrfs_root *root,
3807 		       struct inode *dir, struct inode *inode,
3808 		       const char *name, int name_len);
3809 int btrfs_add_link(struct btrfs_trans_handle *trans,
3810 		   struct inode *parent_inode, struct inode *inode,
3811 		   const char *name, int name_len, int add_backref, u64 index);
3812 int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
3813 			struct btrfs_root *root,
3814 			struct inode *dir, u64 objectid,
3815 			const char *name, int name_len);
3816 int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len,
3817 			int front);
3818 int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans,
3819 			       struct btrfs_root *root,
3820 			       struct inode *inode, u64 new_size,
3821 			       u32 min_type);
3822 
3823 int btrfs_start_delalloc_inodes(struct btrfs_root *root, int delay_iput);
3824 int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, int delay_iput,
3825 			       int nr);
3826 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end,
3827 			      struct extent_state **cached_state);
3828 int btrfs_create_subvol_root(struct btrfs_trans_handle *trans,
3829 			     struct btrfs_root *new_root,
3830 			     struct btrfs_root *parent_root,
3831 			     u64 new_dirid);
3832 int btrfs_merge_bio_hook(int rw, struct page *page, unsigned long offset,
3833 			 size_t size, struct bio *bio,
3834 			 unsigned long bio_flags);
3835 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf);
3836 int btrfs_readpage(struct file *file, struct page *page);
3837 void btrfs_evict_inode(struct inode *inode);
3838 int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc);
3839 struct inode *btrfs_alloc_inode(struct super_block *sb);
3840 void btrfs_destroy_inode(struct inode *inode);
3841 int btrfs_drop_inode(struct inode *inode);
3842 int btrfs_init_cachep(void);
3843 void btrfs_destroy_cachep(void);
3844 long btrfs_ioctl_trans_end(struct file *file);
3845 struct inode *btrfs_iget(struct super_block *s, struct btrfs_key *location,
3846 			 struct btrfs_root *root, int *was_new);
3847 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
3848 				    size_t pg_offset, u64 start, u64 end,
3849 				    int create);
3850 int btrfs_update_inode(struct btrfs_trans_handle *trans,
3851 			      struct btrfs_root *root,
3852 			      struct inode *inode);
3853 int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
3854 				struct btrfs_root *root, struct inode *inode);
3855 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode);
3856 int btrfs_orphan_cleanup(struct btrfs_root *root);
3857 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
3858 			      struct btrfs_root *root);
3859 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size);
3860 void btrfs_invalidate_inodes(struct btrfs_root *root);
3861 void btrfs_add_delayed_iput(struct inode *inode);
3862 void btrfs_run_delayed_iputs(struct btrfs_root *root);
3863 int btrfs_prealloc_file_range(struct inode *inode, int mode,
3864 			      u64 start, u64 num_bytes, u64 min_size,
3865 			      loff_t actual_len, u64 *alloc_hint);
3866 int btrfs_prealloc_file_range_trans(struct inode *inode,
3867 				    struct btrfs_trans_handle *trans, int mode,
3868 				    u64 start, u64 num_bytes, u64 min_size,
3869 				    loff_t actual_len, u64 *alloc_hint);
3870 extern const struct dentry_operations btrfs_dentry_operations;
3871 
3872 /* ioctl.c */
3873 long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
3874 void btrfs_update_iflags(struct inode *inode);
3875 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir);
3876 int btrfs_is_empty_uuid(u8 *uuid);
3877 int btrfs_defrag_file(struct inode *inode, struct file *file,
3878 		      struct btrfs_ioctl_defrag_range_args *range,
3879 		      u64 newer_than, unsigned long max_pages);
3880 void btrfs_get_block_group_info(struct list_head *groups_list,
3881 				struct btrfs_ioctl_space_info *space);
3882 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3883 			       struct btrfs_ioctl_balance_args *bargs);
3884 
3885 
3886 /* file.c */
3887 int btrfs_auto_defrag_init(void);
3888 void btrfs_auto_defrag_exit(void);
3889 int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
3890 			   struct inode *inode);
3891 int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info);
3892 void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info);
3893 int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync);
3894 void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
3895 			     int skip_pinned);
3896 extern const struct file_operations btrfs_file_operations;
3897 int __btrfs_drop_extents(struct btrfs_trans_handle *trans,
3898 			 struct btrfs_root *root, struct inode *inode,
3899 			 struct btrfs_path *path, u64 start, u64 end,
3900 			 u64 *drop_end, int drop_cache,
3901 			 int replace_extent,
3902 			 u32 extent_item_size,
3903 			 int *key_inserted);
3904 int btrfs_drop_extents(struct btrfs_trans_handle *trans,
3905 		       struct btrfs_root *root, struct inode *inode, u64 start,
3906 		       u64 end, int drop_cache);
3907 int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
3908 			      struct inode *inode, u64 start, u64 end);
3909 int btrfs_release_file(struct inode *inode, struct file *file);
3910 int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
3911 		      struct page **pages, size_t num_pages,
3912 		      loff_t pos, size_t write_bytes,
3913 		      struct extent_state **cached);
3914 
3915 /* tree-defrag.c */
3916 int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
3917 			struct btrfs_root *root);
3918 
3919 /* sysfs.c */
3920 int btrfs_init_sysfs(void);
3921 void btrfs_exit_sysfs(void);
3922 int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info);
3923 void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info);
3924 
3925 /* xattr.c */
3926 ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size);
3927 
3928 /* super.c */
3929 int btrfs_parse_options(struct btrfs_root *root, char *options);
3930 int btrfs_sync_fs(struct super_block *sb, int wait);
3931 
3932 #ifdef CONFIG_PRINTK
3933 __printf(2, 3)
3934 void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...);
3935 #else
3936 static inline __printf(2, 3)
3937 void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...)
3938 {
3939 }
3940 #endif
3941 
3942 #define btrfs_emerg(fs_info, fmt, args...) \
3943 	btrfs_printk(fs_info, KERN_EMERG fmt, ##args)
3944 #define btrfs_alert(fs_info, fmt, args...) \
3945 	btrfs_printk(fs_info, KERN_ALERT fmt, ##args)
3946 #define btrfs_crit(fs_info, fmt, args...) \
3947 	btrfs_printk(fs_info, KERN_CRIT fmt, ##args)
3948 #define btrfs_err(fs_info, fmt, args...) \
3949 	btrfs_printk(fs_info, KERN_ERR fmt, ##args)
3950 #define btrfs_warn(fs_info, fmt, args...) \
3951 	btrfs_printk(fs_info, KERN_WARNING fmt, ##args)
3952 #define btrfs_notice(fs_info, fmt, args...) \
3953 	btrfs_printk(fs_info, KERN_NOTICE fmt, ##args)
3954 #define btrfs_info(fs_info, fmt, args...) \
3955 	btrfs_printk(fs_info, KERN_INFO fmt, ##args)
3956 
3957 #ifdef DEBUG
3958 #define btrfs_debug(fs_info, fmt, args...) \
3959 	btrfs_printk(fs_info, KERN_DEBUG fmt, ##args)
3960 #else
3961 #define btrfs_debug(fs_info, fmt, args...) \
3962     no_printk(KERN_DEBUG fmt, ##args)
3963 #endif
3964 
3965 #ifdef CONFIG_BTRFS_ASSERT
3966 
3967 static inline void assfail(char *expr, char *file, int line)
3968 {
3969 	pr_err("BTRFS: assertion failed: %s, file: %s, line: %d",
3970 	       expr, file, line);
3971 	BUG();
3972 }
3973 
3974 #define ASSERT(expr)	\
3975 	(likely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__))
3976 #else
3977 #define ASSERT(expr)	((void)0)
3978 #endif
3979 
3980 #define btrfs_assert()
3981 __printf(5, 6)
3982 void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
3983 		     unsigned int line, int errno, const char *fmt, ...);
3984 
3985 
3986 void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
3987 			       struct btrfs_root *root, const char *function,
3988 			       unsigned int line, int errno);
3989 
3990 #define btrfs_set_fs_incompat(__fs_info, opt) \
3991 	__btrfs_set_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt)
3992 
3993 static inline void __btrfs_set_fs_incompat(struct btrfs_fs_info *fs_info,
3994 					   u64 flag)
3995 {
3996 	struct btrfs_super_block *disk_super;
3997 	u64 features;
3998 
3999 	disk_super = fs_info->super_copy;
4000 	features = btrfs_super_incompat_flags(disk_super);
4001 	if (!(features & flag)) {
4002 		spin_lock(&fs_info->super_lock);
4003 		features = btrfs_super_incompat_flags(disk_super);
4004 		if (!(features & flag)) {
4005 			features |= flag;
4006 			btrfs_set_super_incompat_flags(disk_super, features);
4007 			btrfs_info(fs_info, "setting %llu feature flag",
4008 					 flag);
4009 		}
4010 		spin_unlock(&fs_info->super_lock);
4011 	}
4012 }
4013 
4014 #define btrfs_fs_incompat(fs_info, opt) \
4015 	__btrfs_fs_incompat((fs_info), BTRFS_FEATURE_INCOMPAT_##opt)
4016 
4017 static inline int __btrfs_fs_incompat(struct btrfs_fs_info *fs_info, u64 flag)
4018 {
4019 	struct btrfs_super_block *disk_super;
4020 	disk_super = fs_info->super_copy;
4021 	return !!(btrfs_super_incompat_flags(disk_super) & flag);
4022 }
4023 
4024 /*
4025  * Call btrfs_abort_transaction as early as possible when an error condition is
4026  * detected, that way the exact line number is reported.
4027  */
4028 
4029 #define btrfs_abort_transaction(trans, root, errno)		\
4030 do {								\
4031 	__btrfs_abort_transaction(trans, root, __func__,	\
4032 				  __LINE__, errno);		\
4033 } while (0)
4034 
4035 #define btrfs_std_error(fs_info, errno)				\
4036 do {								\
4037 	if ((errno))						\
4038 		__btrfs_std_error((fs_info), __func__,		\
4039 				   __LINE__, (errno), NULL);	\
4040 } while (0)
4041 
4042 #define btrfs_error(fs_info, errno, fmt, args...)		\
4043 do {								\
4044 	__btrfs_std_error((fs_info), __func__, __LINE__,	\
4045 			  (errno), fmt, ##args);		\
4046 } while (0)
4047 
4048 __printf(5, 6)
4049 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
4050 		   unsigned int line, int errno, const char *fmt, ...);
4051 
4052 /*
4053  * If BTRFS_MOUNT_PANIC_ON_FATAL_ERROR is in mount_opt, __btrfs_panic
4054  * will panic().  Otherwise we BUG() here.
4055  */
4056 #define btrfs_panic(fs_info, errno, fmt, args...)			\
4057 do {									\
4058 	__btrfs_panic(fs_info, __func__, __LINE__, errno, fmt, ##args);	\
4059 	BUG();								\
4060 } while (0)
4061 
4062 /* acl.c */
4063 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
4064 struct posix_acl *btrfs_get_acl(struct inode *inode, int type);
4065 int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type);
4066 int btrfs_init_acl(struct btrfs_trans_handle *trans,
4067 		   struct inode *inode, struct inode *dir);
4068 #else
4069 #define btrfs_get_acl NULL
4070 #define btrfs_set_acl NULL
4071 static inline int btrfs_init_acl(struct btrfs_trans_handle *trans,
4072 				 struct inode *inode, struct inode *dir)
4073 {
4074 	return 0;
4075 }
4076 #endif
4077 
4078 /* relocation.c */
4079 int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start);
4080 int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
4081 			  struct btrfs_root *root);
4082 int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
4083 			    struct btrfs_root *root);
4084 int btrfs_recover_relocation(struct btrfs_root *root);
4085 int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len);
4086 int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
4087 			  struct btrfs_root *root, struct extent_buffer *buf,
4088 			  struct extent_buffer *cow);
4089 void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans,
4090 			      struct btrfs_pending_snapshot *pending,
4091 			      u64 *bytes_to_reserve);
4092 int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
4093 			      struct btrfs_pending_snapshot *pending);
4094 
4095 /* scrub.c */
4096 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
4097 		    u64 end, struct btrfs_scrub_progress *progress,
4098 		    int readonly, int is_dev_replace);
4099 void btrfs_scrub_pause(struct btrfs_root *root);
4100 void btrfs_scrub_continue(struct btrfs_root *root);
4101 int btrfs_scrub_cancel(struct btrfs_fs_info *info);
4102 int btrfs_scrub_cancel_dev(struct btrfs_fs_info *info,
4103 			   struct btrfs_device *dev);
4104 int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
4105 			 struct btrfs_scrub_progress *progress);
4106 
4107 /* dev-replace.c */
4108 void btrfs_bio_counter_inc_blocked(struct btrfs_fs_info *fs_info);
4109 void btrfs_bio_counter_inc_noblocked(struct btrfs_fs_info *fs_info);
4110 void btrfs_bio_counter_dec(struct btrfs_fs_info *fs_info);
4111 
4112 /* reada.c */
4113 struct reada_control {
4114 	struct btrfs_root	*root;		/* tree to prefetch */
4115 	struct btrfs_key	key_start;
4116 	struct btrfs_key	key_end;	/* exclusive */
4117 	atomic_t		elems;
4118 	struct kref		refcnt;
4119 	wait_queue_head_t	wait;
4120 };
4121 struct reada_control *btrfs_reada_add(struct btrfs_root *root,
4122 			      struct btrfs_key *start, struct btrfs_key *end);
4123 int btrfs_reada_wait(void *handle);
4124 void btrfs_reada_detach(void *handle);
4125 int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
4126 			 u64 start, int err);
4127 
4128 static inline int is_fstree(u64 rootid)
4129 {
4130 	if (rootid == BTRFS_FS_TREE_OBJECTID ||
4131 	    (s64)rootid >= (s64)BTRFS_FIRST_FREE_OBJECTID)
4132 		return 1;
4133 	return 0;
4134 }
4135 
4136 static inline int btrfs_defrag_cancelled(struct btrfs_fs_info *fs_info)
4137 {
4138 	return signal_pending(current);
4139 }
4140 
4141 /* Sanity test specific functions */
4142 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
4143 void btrfs_test_destroy_inode(struct inode *inode);
4144 int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
4145 			       u64 rfer, u64 excl);
4146 #endif
4147 
4148 #endif
4149