xref: /linux/fs/ocfs2/ocfs2_fs.h (revision af873fcecef567abf8a3468b06dd4e4aab46da6d)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * ocfs2_fs.h
5  *
6  * On-disk structures for OCFS2.
7  *
8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License, version 2,  as published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public
20  * License along with this program; if not, write to the
21  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
22  * Boston, MA 021110-1307, USA.
23  */
24 
25 #ifndef _OCFS2_FS_H
26 #define _OCFS2_FS_H
27 
28 #include <linux/magic.h>
29 
30 /* Version */
31 #define OCFS2_MAJOR_REV_LEVEL		0
32 #define OCFS2_MINOR_REV_LEVEL          	90
33 
34 /*
35  * An OCFS2 volume starts this way:
36  * Sector 0: Valid ocfs1_vol_disk_hdr that cleanly fails to mount OCFS.
37  * Sector 1: Valid ocfs1_vol_label that cleanly fails to mount OCFS.
38  * Block OCFS2_SUPER_BLOCK_BLKNO: OCFS2 superblock.
39  *
40  * All other structures are found from the superblock information.
41  *
42  * OCFS2_SUPER_BLOCK_BLKNO is in blocks, not sectors.  eg, for a
43  * blocksize of 2K, it is 4096 bytes into disk.
44  */
45 #define OCFS2_SUPER_BLOCK_BLKNO		2
46 
47 /*
48  * Cluster size limits. The maximum is kept arbitrarily at 1 MB, and could
49  * grow if needed.
50  */
51 #define OCFS2_MIN_CLUSTERSIZE		4096
52 #define OCFS2_MAX_CLUSTERSIZE		1048576
53 
54 /*
55  * Blocks cannot be bigger than clusters, so the maximum blocksize is the
56  * minimum cluster size.
57  */
58 #define OCFS2_MIN_BLOCKSIZE		512
59 #define OCFS2_MAX_BLOCKSIZE		OCFS2_MIN_CLUSTERSIZE
60 
61 /* Object signatures */
62 #define OCFS2_SUPER_BLOCK_SIGNATURE	"OCFSV2"
63 #define OCFS2_INODE_SIGNATURE		"INODE01"
64 #define OCFS2_EXTENT_BLOCK_SIGNATURE	"EXBLK01"
65 #define OCFS2_GROUP_DESC_SIGNATURE      "GROUP01"
66 #define OCFS2_XATTR_BLOCK_SIGNATURE	"XATTR01"
67 #define OCFS2_DIR_TRAILER_SIGNATURE	"DIRTRL1"
68 #define OCFS2_DX_ROOT_SIGNATURE		"DXDIR01"
69 #define OCFS2_DX_LEAF_SIGNATURE		"DXLEAF1"
70 #define OCFS2_REFCOUNT_BLOCK_SIGNATURE	"REFCNT1"
71 
72 /* Compatibility flags */
73 #define OCFS2_HAS_COMPAT_FEATURE(sb,mask)			\
74 	( OCFS2_SB(sb)->s_feature_compat & (mask) )
75 #define OCFS2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
76 	( OCFS2_SB(sb)->s_feature_ro_compat & (mask) )
77 #define OCFS2_HAS_INCOMPAT_FEATURE(sb,mask)			\
78 	( OCFS2_SB(sb)->s_feature_incompat & (mask) )
79 #define OCFS2_SET_COMPAT_FEATURE(sb,mask)			\
80 	OCFS2_SB(sb)->s_feature_compat |= (mask)
81 #define OCFS2_SET_RO_COMPAT_FEATURE(sb,mask)			\
82 	OCFS2_SB(sb)->s_feature_ro_compat |= (mask)
83 #define OCFS2_SET_INCOMPAT_FEATURE(sb,mask)			\
84 	OCFS2_SB(sb)->s_feature_incompat |= (mask)
85 #define OCFS2_CLEAR_COMPAT_FEATURE(sb,mask)			\
86 	OCFS2_SB(sb)->s_feature_compat &= ~(mask)
87 #define OCFS2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
88 	OCFS2_SB(sb)->s_feature_ro_compat &= ~(mask)
89 #define OCFS2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
90 	OCFS2_SB(sb)->s_feature_incompat &= ~(mask)
91 
92 #define OCFS2_FEATURE_COMPAT_SUPP	(OCFS2_FEATURE_COMPAT_BACKUP_SB	\
93 					 | OCFS2_FEATURE_COMPAT_JBD2_SB)
94 #define OCFS2_FEATURE_INCOMPAT_SUPP	(OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT \
95 					 | OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC \
96 					 | OCFS2_FEATURE_INCOMPAT_INLINE_DATA \
97 					 | OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP \
98 					 | OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK \
99 					 | OCFS2_FEATURE_INCOMPAT_XATTR \
100 					 | OCFS2_FEATURE_INCOMPAT_META_ECC \
101 					 | OCFS2_FEATURE_INCOMPAT_INDEXED_DIRS \
102 					 | OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE \
103 					 | OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG	\
104 					 | OCFS2_FEATURE_INCOMPAT_CLUSTERINFO \
105 					 | OCFS2_FEATURE_INCOMPAT_APPEND_DIO)
106 #define OCFS2_FEATURE_RO_COMPAT_SUPP	(OCFS2_FEATURE_RO_COMPAT_UNWRITTEN \
107 					 | OCFS2_FEATURE_RO_COMPAT_USRQUOTA \
108 					 | OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)
109 
110 /*
111  * Heartbeat-only devices are missing journals and other files.  The
112  * filesystem driver can't load them, but the library can.  Never put
113  * this in OCFS2_FEATURE_INCOMPAT_SUPP, *ever*.
114  */
115 #define OCFS2_FEATURE_INCOMPAT_HEARTBEAT_DEV	0x0002
116 
117 /*
118  * tunefs sets this incompat flag before starting the resize and clears it
119  * at the end. This flag protects users from inadvertently mounting the fs
120  * after an aborted run without fsck-ing.
121  */
122 #define OCFS2_FEATURE_INCOMPAT_RESIZE_INPROG    0x0004
123 
124 /* Used to denote a non-clustered volume */
125 #define OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT	0x0008
126 
127 /* Support for sparse allocation in b-trees */
128 #define OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC	0x0010
129 
130 /*
131  * Tunefs sets this incompat flag before starting an operation which
132  * would require cleanup on abort. This is done to protect users from
133  * inadvertently mounting the fs after an aborted run without
134  * fsck-ing.
135  *
136  * s_tunefs_flags on the super block describes precisely which
137  * operations were in progress.
138  */
139 #define OCFS2_FEATURE_INCOMPAT_TUNEFS_INPROG	0x0020
140 
141 /* Support for data packed into inode blocks */
142 #define OCFS2_FEATURE_INCOMPAT_INLINE_DATA	0x0040
143 
144 /*
145  * Support for alternate, userspace cluster stacks.  If set, the superblock
146  * field s_cluster_info contains a tag for the alternate stack in use as
147  * well as the name of the cluster being joined.
148  * mount.ocfs2 must pass in a matching stack name.
149  *
150  * If not set, the classic stack will be used.  This is compatbile with
151  * all older versions.
152  */
153 #define OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK	0x0080
154 
155 /* Support for the extended slot map */
156 #define OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP 0x100
157 
158 /* Support for extended attributes */
159 #define OCFS2_FEATURE_INCOMPAT_XATTR		0x0200
160 
161 /* Support for indexed directores */
162 #define OCFS2_FEATURE_INCOMPAT_INDEXED_DIRS	0x0400
163 
164 /* Metadata checksum and error correction */
165 #define OCFS2_FEATURE_INCOMPAT_META_ECC		0x0800
166 
167 /* Refcount tree support */
168 #define OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE	0x1000
169 
170 /* Discontiguous block groups */
171 #define OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG	0x2000
172 
173 /*
174  * Incompat bit to indicate useable clusterinfo with stackflags for all
175  * cluster stacks (userspace adnd o2cb). If this bit is set,
176  * INCOMPAT_USERSPACE_STACK becomes superfluous and thus should not be set.
177  */
178 #define OCFS2_FEATURE_INCOMPAT_CLUSTERINFO	0x4000
179 
180 /*
181  * Append Direct IO support
182  */
183 #define OCFS2_FEATURE_INCOMPAT_APPEND_DIO	0x8000
184 
185 /*
186  * backup superblock flag is used to indicate that this volume
187  * has backup superblocks.
188  */
189 #define OCFS2_FEATURE_COMPAT_BACKUP_SB		0x0001
190 
191 /*
192  * The filesystem will correctly handle journal feature bits.
193  */
194 #define OCFS2_FEATURE_COMPAT_JBD2_SB		0x0002
195 
196 /*
197  * Unwritten extents support.
198  */
199 #define OCFS2_FEATURE_RO_COMPAT_UNWRITTEN	0x0001
200 
201 /*
202  * Maintain quota information for this filesystem
203  */
204 #define OCFS2_FEATURE_RO_COMPAT_USRQUOTA	0x0002
205 #define OCFS2_FEATURE_RO_COMPAT_GRPQUOTA	0x0004
206 
207 
208 /* The byte offset of the first backup block will be 1G.
209  * The following will be 4G, 16G, 64G, 256G and 1T.
210  */
211 #define OCFS2_BACKUP_SB_START			1 << 30
212 
213 /* the max backup superblock nums */
214 #define OCFS2_MAX_BACKUP_SUPERBLOCKS	6
215 
216 /*
217  * Flags on ocfs2_super_block.s_tunefs_flags
218  */
219 #define OCFS2_TUNEFS_INPROG_REMOVE_SLOT		0x0001	/* Removing slots */
220 
221 /*
222  * Flags on ocfs2_dinode.i_flags
223  */
224 #define OCFS2_VALID_FL		(0x00000001)	/* Inode is valid */
225 #define OCFS2_UNUSED2_FL	(0x00000002)
226 #define OCFS2_ORPHANED_FL	(0x00000004)	/* On the orphan list */
227 #define OCFS2_UNUSED3_FL	(0x00000008)
228 /* System inode flags */
229 #define OCFS2_SYSTEM_FL		(0x00000010)	/* System inode */
230 #define OCFS2_SUPER_BLOCK_FL	(0x00000020)	/* Super block */
231 #define OCFS2_LOCAL_ALLOC_FL	(0x00000040)	/* Slot local alloc bitmap */
232 #define OCFS2_BITMAP_FL		(0x00000080)	/* Allocation bitmap */
233 #define OCFS2_JOURNAL_FL	(0x00000100)	/* Slot local journal */
234 #define OCFS2_HEARTBEAT_FL	(0x00000200)	/* Heartbeat area */
235 #define OCFS2_CHAIN_FL		(0x00000400)	/* Chain allocator */
236 #define OCFS2_DEALLOC_FL	(0x00000800)	/* Truncate log */
237 #define OCFS2_QUOTA_FL		(0x00001000)	/* Quota file */
238 #define OCFS2_DIO_ORPHANED_FL	(0X00002000)	/* On the orphan list especially
239 						 * for dio */
240 
241 /*
242  * Flags on ocfs2_dinode.i_dyn_features
243  *
244  * These can change much more often than i_flags. When adding flags,
245  * keep in mind that i_dyn_features is only 16 bits wide.
246  */
247 #define OCFS2_INLINE_DATA_FL	(0x0001)	/* Data stored in inode block */
248 #define OCFS2_HAS_XATTR_FL	(0x0002)
249 #define OCFS2_INLINE_XATTR_FL	(0x0004)
250 #define OCFS2_INDEXED_DIR_FL	(0x0008)
251 #define OCFS2_HAS_REFCOUNT_FL   (0x0010)
252 
253 /* Inode attributes, keep in sync with EXT2 */
254 #define OCFS2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */
255 #define OCFS2_UNRM_FL			FS_UNRM_FL	/* Undelete */
256 #define OCFS2_COMPR_FL			FS_COMPR_FL	/* Compress file */
257 #define OCFS2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */
258 #define OCFS2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */
259 #define OCFS2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */
260 #define OCFS2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */
261 #define OCFS2_NOATIME_FL		FS_NOATIME_FL	/* do not update atime */
262 /* Reserved for compression usage... */
263 #define OCFS2_DIRTY_FL			FS_DIRTY_FL
264 #define OCFS2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */
265 #define OCFS2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */
266 #define OCFS2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */
267 /* End compression flags --- maybe not all used */
268 #define OCFS2_BTREE_FL			FS_BTREE_FL	/* btree format dir */
269 #define OCFS2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */
270 #define OCFS2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */
271 #define OCFS2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */
272 #define OCFS2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */
273 #define OCFS2_DIRSYNC_FL		FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */
274 #define OCFS2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/
275 #define OCFS2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */
276 
277 #define OCFS2_FL_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */
278 #define OCFS2_FL_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */
279 
280 /*
281  * Extent record flags (e_node.leaf.flags)
282  */
283 #define OCFS2_EXT_UNWRITTEN		(0x01)	/* Extent is allocated but
284 						 * unwritten */
285 #define OCFS2_EXT_REFCOUNTED		(0x02)  /* Extent is reference
286 						 * counted in an associated
287 						 * refcount tree */
288 
289 /*
290  * Journal Flags (ocfs2_dinode.id1.journal1.i_flags)
291  */
292 #define OCFS2_JOURNAL_DIRTY_FL	(0x00000001)	/* Journal needs recovery */
293 
294 /*
295  * superblock s_state flags
296  */
297 #define OCFS2_ERROR_FS		(0x00000001)	/* FS saw errors */
298 
299 /* Limit of space in ocfs2_dir_entry */
300 #define OCFS2_MAX_FILENAME_LEN		255
301 
302 /* Maximum slots on an ocfs2 file system */
303 #define OCFS2_MAX_SLOTS			255
304 
305 /* Slot map indicator for an empty slot */
306 #define OCFS2_INVALID_SLOT		-1
307 
308 #define OCFS2_VOL_UUID_LEN		16
309 #define OCFS2_MAX_VOL_LABEL_LEN		64
310 
311 /* The cluster stack fields */
312 #define OCFS2_STACK_LABEL_LEN		4
313 #define OCFS2_CLUSTER_NAME_LEN		16
314 
315 /* Classic (historically speaking) cluster stack */
316 #define OCFS2_CLASSIC_CLUSTER_STACK	"o2cb"
317 
318 /* Journal limits (in bytes) */
319 #define OCFS2_MIN_JOURNAL_SIZE		(4 * 1024 * 1024)
320 
321 /*
322  * Inline extended attribute size (in bytes)
323  * The value chosen should be aligned to 16 byte boundaries.
324  */
325 #define OCFS2_MIN_XATTR_INLINE_SIZE     256
326 
327 /*
328  * Cluster info flags (ocfs2_cluster_info.ci_stackflags)
329  */
330 #define OCFS2_CLUSTER_O2CB_GLOBAL_HEARTBEAT	(0x01)
331 
332 struct ocfs2_system_inode_info {
333 	char	*si_name;
334 	int	si_iflags;
335 	int	si_mode;
336 };
337 
338 /* System file index */
339 enum {
340 	BAD_BLOCK_SYSTEM_INODE = 0,
341 	GLOBAL_INODE_ALLOC_SYSTEM_INODE,
342 	SLOT_MAP_SYSTEM_INODE,
343 #define OCFS2_FIRST_ONLINE_SYSTEM_INODE SLOT_MAP_SYSTEM_INODE
344 	HEARTBEAT_SYSTEM_INODE,
345 	GLOBAL_BITMAP_SYSTEM_INODE,
346 	USER_QUOTA_SYSTEM_INODE,
347 	GROUP_QUOTA_SYSTEM_INODE,
348 #define OCFS2_LAST_GLOBAL_SYSTEM_INODE GROUP_QUOTA_SYSTEM_INODE
349 #define OCFS2_FIRST_LOCAL_SYSTEM_INODE ORPHAN_DIR_SYSTEM_INODE
350 	ORPHAN_DIR_SYSTEM_INODE,
351 	EXTENT_ALLOC_SYSTEM_INODE,
352 	INODE_ALLOC_SYSTEM_INODE,
353 	JOURNAL_SYSTEM_INODE,
354 	LOCAL_ALLOC_SYSTEM_INODE,
355 	TRUNCATE_LOG_SYSTEM_INODE,
356 	LOCAL_USER_QUOTA_SYSTEM_INODE,
357 	LOCAL_GROUP_QUOTA_SYSTEM_INODE,
358 #define OCFS2_LAST_LOCAL_SYSTEM_INODE LOCAL_GROUP_QUOTA_SYSTEM_INODE
359 	NUM_SYSTEM_INODES
360 };
361 #define NUM_GLOBAL_SYSTEM_INODES OCFS2_FIRST_LOCAL_SYSTEM_INODE
362 #define NUM_LOCAL_SYSTEM_INODES	\
363 		(NUM_SYSTEM_INODES - OCFS2_FIRST_LOCAL_SYSTEM_INODE)
364 
365 static struct ocfs2_system_inode_info ocfs2_system_inodes[NUM_SYSTEM_INODES] = {
366 	/* Global system inodes (single copy) */
367 	/* The first two are only used from userspace mfks/tunefs */
368 	[BAD_BLOCK_SYSTEM_INODE]		= { "bad_blocks", 0, S_IFREG | 0644 },
369 	[GLOBAL_INODE_ALLOC_SYSTEM_INODE] 	= { "global_inode_alloc", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
370 
371 	/* These are used by the running filesystem */
372 	[SLOT_MAP_SYSTEM_INODE]			= { "slot_map", 0, S_IFREG | 0644 },
373 	[HEARTBEAT_SYSTEM_INODE]		= { "heartbeat", OCFS2_HEARTBEAT_FL, S_IFREG | 0644 },
374 	[GLOBAL_BITMAP_SYSTEM_INODE]		= { "global_bitmap", 0, S_IFREG | 0644 },
375 	[USER_QUOTA_SYSTEM_INODE]		= { "aquota.user", OCFS2_QUOTA_FL, S_IFREG | 0644 },
376 	[GROUP_QUOTA_SYSTEM_INODE]		= { "aquota.group", OCFS2_QUOTA_FL, S_IFREG | 0644 },
377 
378 	/* Slot-specific system inodes (one copy per slot) */
379 	[ORPHAN_DIR_SYSTEM_INODE]		= { "orphan_dir:%04d", 0, S_IFDIR | 0755 },
380 	[EXTENT_ALLOC_SYSTEM_INODE]		= { "extent_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
381 	[INODE_ALLOC_SYSTEM_INODE]		= { "inode_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
382 	[JOURNAL_SYSTEM_INODE]			= { "journal:%04d", OCFS2_JOURNAL_FL, S_IFREG | 0644 },
383 	[LOCAL_ALLOC_SYSTEM_INODE]		= { "local_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_LOCAL_ALLOC_FL, S_IFREG | 0644 },
384 	[TRUNCATE_LOG_SYSTEM_INODE]		= { "truncate_log:%04d", OCFS2_DEALLOC_FL, S_IFREG | 0644 },
385 	[LOCAL_USER_QUOTA_SYSTEM_INODE]		= { "aquota.user:%04d", OCFS2_QUOTA_FL, S_IFREG | 0644 },
386 	[LOCAL_GROUP_QUOTA_SYSTEM_INODE]	= { "aquota.group:%04d", OCFS2_QUOTA_FL, S_IFREG | 0644 },
387 };
388 
389 /* Parameter passed from mount.ocfs2 to module */
390 #define OCFS2_HB_NONE			"heartbeat=none"
391 #define OCFS2_HB_LOCAL			"heartbeat=local"
392 #define OCFS2_HB_GLOBAL			"heartbeat=global"
393 
394 /*
395  * OCFS2_DIR_PAD defines the directory entries boundaries
396  *
397  * NOTE: It must be a multiple of 4
398  */
399 #define OCFS2_DIR_PAD			4
400 #define OCFS2_DIR_ROUND			(OCFS2_DIR_PAD - 1)
401 #define OCFS2_DIR_MEMBER_LEN 		offsetof(struct ocfs2_dir_entry, name)
402 #define OCFS2_DIR_REC_LEN(name_len)	(((name_len) + OCFS2_DIR_MEMBER_LEN + \
403                                           OCFS2_DIR_ROUND) & \
404 					 ~OCFS2_DIR_ROUND)
405 #define OCFS2_DIR_MIN_REC_LEN	OCFS2_DIR_REC_LEN(1)
406 
407 #define OCFS2_LINK_MAX		32000
408 #define	OCFS2_DX_LINK_MAX	((1U << 31) - 1U)
409 #define	OCFS2_LINKS_HI_SHIFT	16
410 #define	OCFS2_DX_ENTRIES_MAX	(0xffffffffU)
411 
412 
413 /*
414  * Convenience casts
415  */
416 #define OCFS2_RAW_SB(dinode)		(&((dinode)->id2.i_super))
417 
418 /*
419  * Block checking structure.  This is used in metadata to validate the
420  * contents.  If OCFS2_FEATURE_INCOMPAT_META_ECC is not set, it is all
421  * zeros.
422  */
423 struct ocfs2_block_check {
424 /*00*/	__le32 bc_crc32e;	/* 802.3 Ethernet II CRC32 */
425 	__le16 bc_ecc;		/* Single-error-correction parity vector.
426 				   This is a simple Hamming code dependent
427 				   on the blocksize.  OCFS2's maximum
428 				   blocksize, 4K, requires 16 parity bits,
429 				   so we fit in __le16. */
430 	__le16 bc_reserved1;
431 /*08*/
432 };
433 
434 /*
435  * On disk extent record for OCFS2
436  * It describes a range of clusters on disk.
437  *
438  * Length fields are divided into interior and leaf node versions.
439  * This leaves room for a flags field (OCFS2_EXT_*) in the leaf nodes.
440  */
441 struct ocfs2_extent_rec {
442 /*00*/	__le32 e_cpos;		/* Offset into the file, in clusters */
443 	union {
444 		__le32 e_int_clusters; /* Clusters covered by all children */
445 		struct {
446 			__le16 e_leaf_clusters; /* Clusters covered by this
447 						   extent */
448 			__u8 e_reserved1;
449 			__u8 e_flags; /* Extent flags */
450 		};
451 	};
452 	__le64 e_blkno;		/* Physical disk offset, in blocks */
453 /*10*/
454 };
455 
456 struct ocfs2_chain_rec {
457 	__le32 c_free;	/* Number of free bits in this chain. */
458 	__le32 c_total;	/* Number of total bits in this chain */
459 	__le64 c_blkno;	/* Physical disk offset (blocks) of 1st group */
460 };
461 
462 struct ocfs2_truncate_rec {
463 	__le32 t_start;		/* 1st cluster in this log */
464 	__le32 t_clusters;	/* Number of total clusters covered */
465 };
466 
467 /*
468  * On disk extent list for OCFS2 (node in the tree).  Note that this
469  * is contained inside ocfs2_dinode or ocfs2_extent_block, so the
470  * offsets are relative to ocfs2_dinode.id2.i_list or
471  * ocfs2_extent_block.h_list, respectively.
472  */
473 struct ocfs2_extent_list {
474 /*00*/	__le16 l_tree_depth;		/* Extent tree depth from this
475 					   point.  0 means data extents
476 					   hang directly off this
477 					   header (a leaf)
478 					   NOTE: The high 8 bits cannot be
479 					   used - tree_depth is never that big.
480 					*/
481 	__le16 l_count;			/* Number of extent records */
482 	__le16 l_next_free_rec;		/* Next unused extent slot */
483 	__le16 l_reserved1;
484 	__le64 l_reserved2;		/* Pad to
485 					   sizeof(ocfs2_extent_rec) */
486 /*10*/	struct ocfs2_extent_rec l_recs[0];	/* Extent records */
487 };
488 
489 /*
490  * On disk allocation chain list for OCFS2.  Note that this is
491  * contained inside ocfs2_dinode, so the offsets are relative to
492  * ocfs2_dinode.id2.i_chain.
493  */
494 struct ocfs2_chain_list {
495 /*00*/	__le16 cl_cpg;			/* Clusters per Block Group */
496 	__le16 cl_bpc;			/* Bits per cluster */
497 	__le16 cl_count;		/* Total chains in this list */
498 	__le16 cl_next_free_rec;	/* Next unused chain slot */
499 	__le64 cl_reserved1;
500 /*10*/	struct ocfs2_chain_rec cl_recs[0];	/* Chain records */
501 };
502 
503 /*
504  * On disk deallocation log for OCFS2.  Note that this is
505  * contained inside ocfs2_dinode, so the offsets are relative to
506  * ocfs2_dinode.id2.i_dealloc.
507  */
508 struct ocfs2_truncate_log {
509 /*00*/	__le16 tl_count;		/* Total records in this log */
510 	__le16 tl_used;			/* Number of records in use */
511 	__le32 tl_reserved1;
512 /*08*/	struct ocfs2_truncate_rec tl_recs[0];	/* Truncate records */
513 };
514 
515 /*
516  * On disk extent block (indirect block) for OCFS2
517  */
518 struct ocfs2_extent_block
519 {
520 /*00*/	__u8 h_signature[8];		/* Signature for verification */
521 	struct ocfs2_block_check h_check;	/* Error checking */
522 /*10*/	__le16 h_suballoc_slot;		/* Slot suballocator this
523 					   extent_header belongs to */
524 	__le16 h_suballoc_bit;		/* Bit offset in suballocator
525 					   block group */
526 	__le32 h_fs_generation;		/* Must match super block */
527 	__le64 h_blkno;			/* Offset on disk, in blocks */
528 /*20*/	__le64 h_suballoc_loc;		/* Suballocator block group this
529 					   eb belongs to.  Only valid
530 					   if allocated from a
531 					   discontiguous block group */
532 	__le64 h_next_leaf_blk;		/* Offset on disk, in blocks,
533 					   of next leaf header pointing
534 					   to data */
535 /*30*/	struct ocfs2_extent_list h_list;	/* Extent record list */
536 /* Actual on-disk size is one block */
537 };
538 
539 /*
540  * On disk slot map for OCFS2.  This defines the contents of the "slot_map"
541  * system file.  A slot is valid if it contains a node number >= 0.  The
542  * value -1 (0xFFFF) is OCFS2_INVALID_SLOT.  This marks a slot empty.
543  */
544 struct ocfs2_slot_map {
545 /*00*/	__le16 sm_slots[0];
546 /*
547  * Actual on-disk size is one block.  OCFS2_MAX_SLOTS is 255,
548  * 255 * sizeof(__le16) == 512B, within the 512B block minimum blocksize.
549  */
550 };
551 
552 struct ocfs2_extended_slot {
553 /*00*/	__u8	es_valid;
554 	__u8	es_reserved1[3];
555 	__le32	es_node_num;
556 /*08*/
557 };
558 
559 /*
560  * The extended slot map, used when OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP
561  * is set.  It separates out the valid marker from the node number, and
562  * has room to grow.  Unlike the old slot map, this format is defined by
563  * i_size.
564  */
565 struct ocfs2_slot_map_extended {
566 /*00*/	struct ocfs2_extended_slot se_slots[0];
567 /*
568  * Actual size is i_size of the slot_map system file.  It should
569  * match s_max_slots * sizeof(struct ocfs2_extended_slot)
570  */
571 };
572 
573 /*
574  * ci_stackflags is only valid if the incompat bit
575  * OCFS2_FEATURE_INCOMPAT_CLUSTERINFO is set.
576  */
577 struct ocfs2_cluster_info {
578 /*00*/	__u8   ci_stack[OCFS2_STACK_LABEL_LEN];
579 	union {
580 		__le32 ci_reserved;
581 		struct {
582 			__u8 ci_stackflags;
583 			__u8 ci_reserved1;
584 			__u8 ci_reserved2;
585 			__u8 ci_reserved3;
586 		};
587 	};
588 /*08*/	__u8   ci_cluster[OCFS2_CLUSTER_NAME_LEN];
589 /*18*/
590 };
591 
592 /*
593  * On disk superblock for OCFS2
594  * Note that it is contained inside an ocfs2_dinode, so all offsets
595  * are relative to the start of ocfs2_dinode.id2.
596  */
597 struct ocfs2_super_block {
598 /*00*/	__le16 s_major_rev_level;
599 	__le16 s_minor_rev_level;
600 	__le16 s_mnt_count;
601 	__le16 s_max_mnt_count;
602 	__le16 s_state;			/* File system state */
603 	__le16 s_errors;			/* Behaviour when detecting errors */
604 	__le32 s_checkinterval;		/* Max time between checks */
605 /*10*/	__le64 s_lastcheck;		/* Time of last check */
606 	__le32 s_creator_os;		/* OS */
607 	__le32 s_feature_compat;		/* Compatible feature set */
608 /*20*/	__le32 s_feature_incompat;	/* Incompatible feature set */
609 	__le32 s_feature_ro_compat;	/* Readonly-compatible feature set */
610 	__le64 s_root_blkno;		/* Offset, in blocks, of root directory
611 					   dinode */
612 /*30*/	__le64 s_system_dir_blkno;	/* Offset, in blocks, of system
613 					   directory dinode */
614 	__le32 s_blocksize_bits;		/* Blocksize for this fs */
615 	__le32 s_clustersize_bits;	/* Clustersize for this fs */
616 /*40*/	__le16 s_max_slots;		/* Max number of simultaneous mounts
617 					   before tunefs required */
618 	__le16 s_tunefs_flag;
619 	__le32 s_uuid_hash;		/* hash value of uuid */
620 	__le64 s_first_cluster_group;	/* Block offset of 1st cluster
621 					 * group header */
622 /*50*/	__u8  s_label[OCFS2_MAX_VOL_LABEL_LEN];	/* Label for mounting, etc. */
623 /*90*/	__u8  s_uuid[OCFS2_VOL_UUID_LEN];	/* 128-bit uuid */
624 /*A0*/  struct ocfs2_cluster_info s_cluster_info; /* Only valid if either
625 						     userspace or clusterinfo
626 						     INCOMPAT flag set. */
627 /*B8*/	__le16 s_xattr_inline_size;	/* extended attribute inline size
628 					   for this fs*/
629 	__le16 s_reserved0;
630 	__le32 s_dx_seed[3];		/* seed[0-2] for dx dir hash.
631 					 * s_uuid_hash serves as seed[3]. */
632 /*C0*/  __le64 s_reserved2[15];		/* Fill out superblock */
633 /*140*/
634 
635 	/*
636 	 * NOTE: As stated above, all offsets are relative to
637 	 * ocfs2_dinode.id2, which is at 0xC0 in the inode.
638 	 * 0xC0 + 0x140 = 0x200 or 512 bytes.  A superblock must fit within
639 	 * our smallest blocksize, which is 512 bytes.  To ensure this,
640 	 * we reserve the space in s_reserved2.  Anything past s_reserved2
641 	 * will not be available on the smallest blocksize.
642 	 */
643 };
644 
645 /*
646  * Local allocation bitmap for OCFS2 slots
647  * Note that it exists inside an ocfs2_dinode, so all offsets are
648  * relative to the start of ocfs2_dinode.id2.
649  */
650 struct ocfs2_local_alloc
651 {
652 /*00*/	__le32 la_bm_off;	/* Starting bit offset in main bitmap */
653 	__le16 la_size;		/* Size of included bitmap, in bytes */
654 	__le16 la_reserved1;
655 	__le64 la_reserved2;
656 /*10*/	__u8   la_bitmap[0];
657 };
658 
659 /*
660  * Data-in-inode header. This is only used if i_dyn_features has
661  * OCFS2_INLINE_DATA_FL set.
662  */
663 struct ocfs2_inline_data
664 {
665 /*00*/	__le16	id_count;	/* Number of bytes that can be used
666 				 * for data, starting at id_data */
667 	__le16	id_reserved0;
668 	__le32	id_reserved1;
669 	__u8	id_data[0];	/* Start of user data */
670 };
671 
672 /*
673  * On disk inode for OCFS2
674  */
675 struct ocfs2_dinode {
676 /*00*/	__u8 i_signature[8];		/* Signature for validation */
677 	__le32 i_generation;		/* Generation number */
678 	__le16 i_suballoc_slot;		/* Slot suballocator this inode
679 					   belongs to */
680 	__le16 i_suballoc_bit;		/* Bit offset in suballocator
681 					   block group */
682 /*10*/	__le16 i_links_count_hi;	/* High 16 bits of links count */
683 	__le16 i_xattr_inline_size;
684 	__le32 i_clusters;		/* Cluster count */
685 	__le32 i_uid;			/* Owner UID */
686 	__le32 i_gid;			/* Owning GID */
687 /*20*/	__le64 i_size;			/* Size in bytes */
688 	__le16 i_mode;			/* File mode */
689 	__le16 i_links_count;		/* Links count */
690 	__le32 i_flags;			/* File flags */
691 /*30*/	__le64 i_atime;			/* Access time */
692 	__le64 i_ctime;			/* Creation time */
693 /*40*/	__le64 i_mtime;			/* Modification time */
694 	__le64 i_dtime;			/* Deletion time */
695 /*50*/	__le64 i_blkno;			/* Offset on disk, in blocks */
696 	__le64 i_last_eb_blk;		/* Pointer to last extent
697 					   block */
698 /*60*/	__le32 i_fs_generation;		/* Generation per fs-instance */
699 	__le32 i_atime_nsec;
700 	__le32 i_ctime_nsec;
701 	__le32 i_mtime_nsec;
702 /*70*/	__le32 i_attr;
703 	__le16 i_orphaned_slot;		/* Only valid when OCFS2_ORPHANED_FL
704 					   was set in i_flags */
705 	__le16 i_dyn_features;
706 	__le64 i_xattr_loc;
707 /*80*/	struct ocfs2_block_check i_check;	/* Error checking */
708 /*88*/	__le64 i_dx_root;		/* Pointer to dir index root block */
709 /*90*/	__le64 i_refcount_loc;
710 	__le64 i_suballoc_loc;		/* Suballocator block group this
711 					   inode belongs to.  Only valid
712 					   if allocated from a
713 					   discontiguous block group */
714 /*A0*/	__le16 i_dio_orphaned_slot;	/* only used for append dio write */
715 	__le16 i_reserved1[3];
716 	__le64 i_reserved2[2];
717 /*B8*/	union {
718 		__le64 i_pad1;		/* Generic way to refer to this
719 					   64bit union */
720 		struct {
721 			__le64 i_rdev;	/* Device number */
722 		} dev1;
723 		struct {		/* Info for bitmap system
724 					   inodes */
725 			__le32 i_used;	/* Bits (ie, clusters) used  */
726 			__le32 i_total;	/* Total bits (clusters)
727 					   available */
728 		} bitmap1;
729 		struct {		/* Info for journal system
730 					   inodes */
731 			__le32 ij_flags;	/* Mounted, version, etc. */
732 			__le32 ij_recovery_generation; /* Incremented when the
733 							  journal is recovered
734 							  after an unclean
735 							  shutdown */
736 		} journal1;
737 	} id1;				/* Inode type dependent 1 */
738 /*C0*/	union {
739 		struct ocfs2_super_block	i_super;
740 		struct ocfs2_local_alloc	i_lab;
741 		struct ocfs2_chain_list		i_chain;
742 		struct ocfs2_extent_list	i_list;
743 		struct ocfs2_truncate_log	i_dealloc;
744 		struct ocfs2_inline_data	i_data;
745 		__u8               		i_symlink[0];
746 	} id2;
747 /* Actual on-disk size is one block */
748 };
749 
750 /*
751  * On-disk directory entry structure for OCFS2
752  *
753  * Packed as this structure could be accessed unaligned on 64-bit platforms
754  */
755 struct ocfs2_dir_entry {
756 /*00*/	__le64   inode;                  /* Inode number */
757 	__le16   rec_len;                /* Directory entry length */
758 	__u8    name_len;               /* Name length */
759 	__u8    file_type;
760 /*0C*/	char    name[OCFS2_MAX_FILENAME_LEN];   /* File name */
761 /* Actual on-disk length specified by rec_len */
762 } __attribute__ ((packed));
763 
764 /*
765  * Per-block record for the unindexed directory btree. This is carefully
766  * crafted so that the rec_len and name_len records of an ocfs2_dir_entry are
767  * mirrored. That way, the directory manipulation code needs a minimal amount
768  * of update.
769  *
770  * NOTE: Keep this structure aligned to a multiple of 4 bytes.
771  */
772 struct ocfs2_dir_block_trailer {
773 /*00*/	__le64		db_compat_inode;	/* Always zero. Was inode */
774 
775 	__le16		db_compat_rec_len;	/* Backwards compatible with
776 						 * ocfs2_dir_entry. */
777 	__u8		db_compat_name_len;	/* Always zero. Was name_len */
778 	__u8		db_reserved0;
779 	__le16		db_reserved1;
780 	__le16		db_free_rec_len;	/* Size of largest empty hole
781 						 * in this block. (unused) */
782 /*10*/	__u8		db_signature[8];	/* Signature for verification */
783 	__le64		db_reserved2;
784 /*20*/	__le64		db_free_next;		/* Next block in list (unused) */
785 	__le64		db_blkno;		/* Offset on disk, in blocks */
786 /*30*/	__le64		db_parent_dinode;	/* dinode which owns me, in
787 						   blocks */
788 	struct ocfs2_block_check db_check;	/* Error checking */
789 /*40*/
790 };
791 
792  /*
793  * A directory entry in the indexed tree. We don't store the full name here,
794  * but instead provide a pointer to the full dirent in the unindexed tree.
795  *
796  * We also store name_len here so as to reduce the number of leaf blocks we
797  * need to search in case of collisions.
798  */
799 struct ocfs2_dx_entry {
800 	__le32		dx_major_hash;	/* Used to find logical
801 					 * cluster in index */
802 	__le32		dx_minor_hash;	/* Lower bits used to find
803 					 * block in cluster */
804 	__le64		dx_dirent_blk;	/* Physical block in unindexed
805 					 * tree holding this dirent. */
806 };
807 
808 struct ocfs2_dx_entry_list {
809 	__le32		de_reserved;
810 	__le16		de_count;	/* Maximum number of entries
811 					 * possible in de_entries */
812 	__le16		de_num_used;	/* Current number of
813 					 * de_entries entries */
814 	struct	ocfs2_dx_entry		de_entries[0];	/* Indexed dir entries
815 							 * in a packed array of
816 							 * length de_num_used */
817 };
818 
819 #define OCFS2_DX_FLAG_INLINE	0x01
820 
821 /*
822  * A directory indexing block. Each indexed directory has one of these,
823  * pointed to by ocfs2_dinode.
824  *
825  * This block stores an indexed btree root, and a set of free space
826  * start-of-list pointers.
827  */
828 struct ocfs2_dx_root_block {
829 	__u8		dr_signature[8];	/* Signature for verification */
830 	struct ocfs2_block_check dr_check;	/* Error checking */
831 	__le16		dr_suballoc_slot;	/* Slot suballocator this
832 						 * block belongs to. */
833 	__le16		dr_suballoc_bit;	/* Bit offset in suballocator
834 						 * block group */
835 	__le32		dr_fs_generation;	/* Must match super block */
836 	__le64		dr_blkno;		/* Offset on disk, in blocks */
837 	__le64		dr_last_eb_blk;		/* Pointer to last
838 						 * extent block */
839 	__le32		dr_clusters;		/* Clusters allocated
840 						 * to the indexed tree. */
841 	__u8		dr_flags;		/* OCFS2_DX_FLAG_* flags */
842 	__u8		dr_reserved0;
843 	__le16		dr_reserved1;
844 	__le64		dr_dir_blkno;		/* Pointer to parent inode */
845 	__le32		dr_num_entries;		/* Total number of
846 						 * names stored in
847 						 * this directory.*/
848 	__le32		dr_reserved2;
849 	__le64		dr_free_blk;		/* Pointer to head of free
850 						 * unindexed block list. */
851 	__le64		dr_suballoc_loc;	/* Suballocator block group
852 						   this root belongs to.
853 						   Only valid if allocated
854 						   from a discontiguous
855 						   block group */
856 	__le64		dr_reserved3[14];
857 	union {
858 		struct ocfs2_extent_list dr_list; /* Keep this aligned to 128
859 						   * bits for maximum space
860 						   * efficiency. */
861 		struct ocfs2_dx_entry_list dr_entries; /* In-root-block list of
862 							* entries. We grow out
863 							* to extents if this
864 							* gets too big. */
865 	};
866 };
867 
868 /*
869  * The header of a leaf block in the indexed tree.
870  */
871 struct ocfs2_dx_leaf {
872 	__u8		dl_signature[8];/* Signature for verification */
873 	struct ocfs2_block_check dl_check;	/* Error checking */
874 	__le64		dl_blkno;	/* Offset on disk, in blocks */
875 	__le32		dl_fs_generation;/* Must match super block */
876 	__le32		dl_reserved0;
877 	__le64		dl_reserved1;
878 	struct ocfs2_dx_entry_list	dl_list;
879 };
880 
881 /*
882  * Largest bitmap for a block (suballocator) group in bytes.  This limit
883  * does not affect cluster groups (global allocator).  Cluster group
884  * bitmaps run to the end of the block.
885  */
886 #define OCFS2_MAX_BG_BITMAP_SIZE	256
887 
888 /*
889  * On disk allocator group structure for OCFS2
890  */
891 struct ocfs2_group_desc
892 {
893 /*00*/	__u8    bg_signature[8];        /* Signature for validation */
894 	__le16   bg_size;                /* Size of included bitmap in
895 					   bytes. */
896 	__le16   bg_bits;                /* Bits represented by this
897 					   group. */
898 	__le16	bg_free_bits_count;     /* Free bits count */
899 	__le16   bg_chain;               /* What chain I am in. */
900 /*10*/	__le32   bg_generation;
901 	__le32	bg_reserved1;
902 	__le64   bg_next_group;          /* Next group in my list, in
903 					   blocks */
904 /*20*/	__le64   bg_parent_dinode;       /* dinode which owns me, in
905 					   blocks */
906 	__le64   bg_blkno;               /* Offset on disk, in blocks */
907 /*30*/	struct ocfs2_block_check bg_check;	/* Error checking */
908 	__le64   bg_reserved2;
909 /*40*/	union {
910 		__u8    bg_bitmap[0];
911 		struct {
912 			/*
913 			 * Block groups may be discontiguous when
914 			 * OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG is set.
915 			 * The extents of a discontiguous block group are
916 			 * stored in bg_list.  It is a flat list.
917 			 * l_tree_depth must always be zero.  A
918 			 * discontiguous group is signified by a non-zero
919 			 * bg_list->l_next_free_rec.  Only block groups
920 			 * can be discontiguous; Cluster groups cannot.
921 			 * We've never made a block group with more than
922 			 * 2048 blocks (256 bytes of bg_bitmap).  This
923 			 * codifies that limit so that we can fit bg_list.
924 			 * bg_size of a discontiguous block group will
925 			 * be 256 to match bg_bitmap_filler.
926 			 */
927 			__u8 bg_bitmap_filler[OCFS2_MAX_BG_BITMAP_SIZE];
928 /*140*/			struct ocfs2_extent_list bg_list;
929 		};
930 	};
931 /* Actual on-disk size is one block */
932 };
933 
934 struct ocfs2_refcount_rec {
935 /*00*/	__le64 r_cpos;		/* Physical offset, in clusters */
936 	__le32 r_clusters;	/* Clusters covered by this extent */
937 	__le32 r_refcount;	/* Reference count of this extent */
938 /*10*/
939 };
940 #define OCFS2_32BIT_POS_MASK		(0xffffffffULL)
941 
942 #define OCFS2_REFCOUNT_LEAF_FL          (0x00000001)
943 #define OCFS2_REFCOUNT_TREE_FL          (0x00000002)
944 
945 struct ocfs2_refcount_list {
946 /*00*/	__le16 rl_count;	/* Maximum number of entries possible
947 				   in rl_records */
948 	__le16 rl_used;		/* Current number of used records */
949 	__le32 rl_reserved2;
950 	__le64 rl_reserved1;	/* Pad to sizeof(ocfs2_refcount_record) */
951 /*10*/	struct ocfs2_refcount_rec rl_recs[0];	/* Refcount records */
952 };
953 
954 
955 struct ocfs2_refcount_block {
956 /*00*/	__u8 rf_signature[8];		/* Signature for verification */
957 	__le16 rf_suballoc_slot;	/* Slot suballocator this block
958 					   belongs to */
959 	__le16 rf_suballoc_bit;		/* Bit offset in suballocator
960 					   block group */
961 	__le32 rf_fs_generation;	/* Must match superblock */
962 /*10*/	__le64 rf_blkno;		/* Offset on disk, in blocks */
963 	__le64 rf_parent;		/* Parent block, only valid if
964 					   OCFS2_REFCOUNT_LEAF_FL is set in
965 					   rf_flags */
966 /*20*/	struct ocfs2_block_check rf_check;	/* Error checking */
967 	__le64 rf_last_eb_blk;		/* Pointer to last extent block */
968 /*30*/	__le32 rf_count;		/* Number of inodes sharing this
969 					   refcount tree */
970 	__le32 rf_flags;		/* See the flags above */
971 	__le32 rf_clusters;		/* clusters covered by refcount tree. */
972 	__le32 rf_cpos;			/* cluster offset in refcount tree.*/
973 /*40*/	__le32 rf_generation;		/* generation number. all be the same
974 					 * for the same refcount tree. */
975 	__le32 rf_reserved0;
976 	__le64 rf_suballoc_loc;		/* Suballocator block group this
977 					   refcount block belongs to. Only
978 					   valid if allocated from a
979 					   discontiguous block group */
980 /*50*/	__le64 rf_reserved1[6];
981 /*80*/	union {
982 		struct ocfs2_refcount_list rf_records;  /* List of refcount
983 							  records */
984 		struct ocfs2_extent_list rf_list;	/* Extent record list,
985 							only valid if
986 							OCFS2_REFCOUNT_TREE_FL
987 							is set in rf_flags */
988 	};
989 /* Actual on-disk size is one block */
990 };
991 
992 /*
993  * On disk extended attribute structure for OCFS2.
994  */
995 
996 /*
997  * ocfs2_xattr_entry indicates one extend attribute.
998  *
999  * Note that it can be stored in inode, one block or one xattr bucket.
1000  */
1001 struct ocfs2_xattr_entry {
1002 	__le32	xe_name_hash;    /* hash value of xattr prefix+suffix. */
1003 	__le16	xe_name_offset;  /* byte offset from the 1st entry in the
1004 				    local xattr storage(inode, xattr block or
1005 				    xattr bucket). */
1006 	__u8	xe_name_len;	 /* xattr name len, doesn't include prefix. */
1007 	__u8	xe_type;         /* the low 7 bits indicate the name prefix
1008 				  * type and the highest bit indicates whether
1009 				  * the EA is stored in the local storage. */
1010 	__le64	xe_value_size;	 /* real xattr value length. */
1011 };
1012 
1013 /*
1014  * On disk structure for xattr header.
1015  *
1016  * One ocfs2_xattr_header describes how many ocfs2_xattr_entry records in
1017  * the local xattr storage.
1018  */
1019 struct ocfs2_xattr_header {
1020 	__le16	xh_count;                       /* contains the count of how
1021 						   many records are in the
1022 						   local xattr storage. */
1023 	__le16	xh_free_start;                  /* current offset for storing
1024 						   xattr. */
1025 	__le16	xh_name_value_len;              /* total length of name/value
1026 						   length in this bucket. */
1027 	__le16	xh_num_buckets;                 /* Number of xattr buckets
1028 						   in this extent record,
1029 						   only valid in the first
1030 						   bucket. */
1031 	struct ocfs2_block_check xh_check;	/* Error checking
1032 						   (Note, this is only
1033 						    used for xattr
1034 						    buckets.  A block uses
1035 						    xb_check and sets
1036 						    this field to zero.) */
1037 	struct ocfs2_xattr_entry xh_entries[0]; /* xattr entry list. */
1038 };
1039 
1040 /*
1041  * On disk structure for xattr value root.
1042  *
1043  * When an xattr's value is large enough, it is stored in an external
1044  * b-tree like file data.  The xattr value root points to this structure.
1045  */
1046 struct ocfs2_xattr_value_root {
1047 /*00*/	__le32	xr_clusters;              /* clusters covered by xattr value. */
1048 	__le32	xr_reserved0;
1049 	__le64	xr_last_eb_blk;           /* Pointer to last extent block */
1050 /*10*/	struct ocfs2_extent_list xr_list; /* Extent record list */
1051 };
1052 
1053 /*
1054  * On disk structure for xattr tree root.
1055  *
1056  * It is used when there are too many extended attributes for one file. These
1057  * attributes will be organized and stored in an indexed-btree.
1058  */
1059 struct ocfs2_xattr_tree_root {
1060 /*00*/	__le32	xt_clusters;              /* clusters covered by xattr. */
1061 	__le32	xt_reserved0;
1062 	__le64	xt_last_eb_blk;           /* Pointer to last extent block */
1063 /*10*/	struct ocfs2_extent_list xt_list; /* Extent record list */
1064 };
1065 
1066 #define OCFS2_XATTR_INDEXED	0x1
1067 #define OCFS2_HASH_SHIFT	5
1068 #define OCFS2_XATTR_ROUND	3
1069 #define OCFS2_XATTR_SIZE(size)	(((size) + OCFS2_XATTR_ROUND) & \
1070 				~(OCFS2_XATTR_ROUND))
1071 
1072 #define OCFS2_XATTR_BUCKET_SIZE			4096
1073 #define OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET 	(OCFS2_XATTR_BUCKET_SIZE \
1074 						 / OCFS2_MIN_BLOCKSIZE)
1075 
1076 /*
1077  * On disk structure for xattr block.
1078  */
1079 struct ocfs2_xattr_block {
1080 /*00*/	__u8	xb_signature[8];     /* Signature for verification */
1081 	__le16	xb_suballoc_slot;    /* Slot suballocator this
1082 					block belongs to. */
1083 	__le16	xb_suballoc_bit;     /* Bit offset in suballocator
1084 					block group */
1085 	__le32	xb_fs_generation;    /* Must match super block */
1086 /*10*/	__le64	xb_blkno;            /* Offset on disk, in blocks */
1087 	struct ocfs2_block_check xb_check;	/* Error checking */
1088 /*20*/	__le16	xb_flags;            /* Indicates whether this block contains
1089 					real xattr or a xattr tree. */
1090 	__le16	xb_reserved0;
1091 	__le32  xb_reserved1;
1092 	__le64	xb_suballoc_loc;	/* Suballocator block group this
1093 					   xattr block belongs to. Only
1094 					   valid if allocated from a
1095 					   discontiguous block group */
1096 /*30*/	union {
1097 		struct ocfs2_xattr_header xb_header; /* xattr header if this
1098 							block contains xattr */
1099 		struct ocfs2_xattr_tree_root xb_root;/* xattr tree root if this
1100 							block cotains xattr
1101 							tree. */
1102 	} xb_attrs;
1103 };
1104 
1105 #define OCFS2_XATTR_ENTRY_LOCAL		0x80
1106 #define OCFS2_XATTR_TYPE_MASK		0x7F
1107 static inline void ocfs2_xattr_set_local(struct ocfs2_xattr_entry *xe,
1108 					 int local)
1109 {
1110 	if (local)
1111 		xe->xe_type |= OCFS2_XATTR_ENTRY_LOCAL;
1112 	else
1113 		xe->xe_type &= ~OCFS2_XATTR_ENTRY_LOCAL;
1114 }
1115 
1116 static inline int ocfs2_xattr_is_local(struct ocfs2_xattr_entry *xe)
1117 {
1118 	return xe->xe_type & OCFS2_XATTR_ENTRY_LOCAL;
1119 }
1120 
1121 static inline void ocfs2_xattr_set_type(struct ocfs2_xattr_entry *xe, int type)
1122 {
1123 	xe->xe_type |= type & OCFS2_XATTR_TYPE_MASK;
1124 }
1125 
1126 static inline int ocfs2_xattr_get_type(struct ocfs2_xattr_entry *xe)
1127 {
1128 	return xe->xe_type & OCFS2_XATTR_TYPE_MASK;
1129 }
1130 
1131 /*
1132  *  On disk structures for global quota file
1133  */
1134 
1135 /* Magic numbers and known versions for global quota files */
1136 #define OCFS2_GLOBAL_QMAGICS {\
1137 	0x0cf52470, /* USRQUOTA */ \
1138 	0x0cf52471  /* GRPQUOTA */ \
1139 }
1140 
1141 #define OCFS2_GLOBAL_QVERSIONS {\
1142 	0, \
1143 	0, \
1144 }
1145 
1146 
1147 /* Each block of each quota file has a certain fixed number of bytes reserved
1148  * for OCFS2 internal use at its end. OCFS2 can use it for things like
1149  * checksums, etc. */
1150 #define OCFS2_QBLK_RESERVED_SPACE 8
1151 
1152 /* Generic header of all quota files */
1153 struct ocfs2_disk_dqheader {
1154 	__le32 dqh_magic;	/* Magic number identifying file */
1155 	__le32 dqh_version;	/* Quota format version */
1156 };
1157 
1158 #define OCFS2_GLOBAL_INFO_OFF (sizeof(struct ocfs2_disk_dqheader))
1159 
1160 /* Information header of global quota file (immediately follows the generic
1161  * header) */
1162 struct ocfs2_global_disk_dqinfo {
1163 /*00*/	__le32 dqi_bgrace;	/* Grace time for space softlimit excess */
1164 	__le32 dqi_igrace;	/* Grace time for inode softlimit excess */
1165 	__le32 dqi_syncms;	/* Time after which we sync local changes to
1166 				 * global quota file */
1167 	__le32 dqi_blocks;	/* Number of blocks in quota file */
1168 /*10*/	__le32 dqi_free_blk;	/* First free block in quota file */
1169 	__le32 dqi_free_entry;	/* First block with free dquot entry in quota
1170 				 * file */
1171 };
1172 
1173 /* Structure with global user / group information. We reserve some space
1174  * for future use. */
1175 struct ocfs2_global_disk_dqblk {
1176 /*00*/	__le32 dqb_id;          /* ID the structure belongs to */
1177 	__le32 dqb_use_count;   /* Number of nodes having reference to this structure */
1178 	__le64 dqb_ihardlimit;  /* absolute limit on allocated inodes */
1179 /*10*/	__le64 dqb_isoftlimit;  /* preferred inode limit */
1180 	__le64 dqb_curinodes;   /* current # allocated inodes */
1181 /*20*/	__le64 dqb_bhardlimit;  /* absolute limit on disk space */
1182 	__le64 dqb_bsoftlimit;  /* preferred limit on disk space */
1183 /*30*/	__le64 dqb_curspace;    /* current space occupied */
1184 	__le64 dqb_btime;       /* time limit for excessive disk use */
1185 /*40*/	__le64 dqb_itime;       /* time limit for excessive inode use */
1186 	__le64 dqb_pad1;
1187 /*50*/	__le64 dqb_pad2;
1188 };
1189 
1190 /*
1191  *  On-disk structures for local quota file
1192  */
1193 
1194 /* Magic numbers and known versions for local quota files */
1195 #define OCFS2_LOCAL_QMAGICS {\
1196 	0x0cf524c0, /* USRQUOTA */ \
1197 	0x0cf524c1  /* GRPQUOTA */ \
1198 }
1199 
1200 #define OCFS2_LOCAL_QVERSIONS {\
1201 	0, \
1202 	0, \
1203 }
1204 
1205 /* Quota flags in dqinfo header */
1206 #define OLQF_CLEAN	0x0001	/* Quota file is empty (this should be after\
1207 				 * quota has been cleanly turned off) */
1208 
1209 #define OCFS2_LOCAL_INFO_OFF (sizeof(struct ocfs2_disk_dqheader))
1210 
1211 /* Information header of local quota file (immediately follows the generic
1212  * header) */
1213 struct ocfs2_local_disk_dqinfo {
1214 	__le32 dqi_flags;	/* Flags for quota file */
1215 	__le32 dqi_chunks;	/* Number of chunks of quota structures
1216 				 * with a bitmap */
1217 	__le32 dqi_blocks;	/* Number of blocks allocated for quota file */
1218 };
1219 
1220 /* Header of one chunk of a quota file */
1221 struct ocfs2_local_disk_chunk {
1222 	__le32 dqc_free;	/* Number of free entries in the bitmap */
1223 	__u8 dqc_bitmap[0];	/* Bitmap of entries in the corresponding
1224 				 * chunk of quota file */
1225 };
1226 
1227 /* One entry in local quota file */
1228 struct ocfs2_local_disk_dqblk {
1229 /*00*/	__le64 dqb_id;		/* id this quota applies to */
1230 	__le64 dqb_spacemod;	/* Change in the amount of used space */
1231 /*10*/	__le64 dqb_inodemod;	/* Change in the amount of used inodes */
1232 };
1233 
1234 
1235 /*
1236  * The quota trailer lives at the end of each quota block.
1237  */
1238 
1239 struct ocfs2_disk_dqtrailer {
1240 /*00*/	struct ocfs2_block_check dq_check;	/* Error checking */
1241 /*08*/	/* Cannot be larger than OCFS2_QBLK_RESERVED_SPACE */
1242 };
1243 
1244 static inline struct ocfs2_disk_dqtrailer *ocfs2_block_dqtrailer(int blocksize,
1245 								 void *buf)
1246 {
1247 	char *ptr = buf;
1248 	ptr += blocksize - OCFS2_QBLK_RESERVED_SPACE;
1249 
1250 	return (struct ocfs2_disk_dqtrailer *)ptr;
1251 }
1252 
1253 #ifdef __KERNEL__
1254 static inline int ocfs2_fast_symlink_chars(struct super_block *sb)
1255 {
1256 	return  sb->s_blocksize -
1257 		 offsetof(struct ocfs2_dinode, id2.i_symlink);
1258 }
1259 
1260 static inline int ocfs2_max_inline_data_with_xattr(struct super_block *sb,
1261 						   struct ocfs2_dinode *di)
1262 {
1263 	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
1264 
1265 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
1266 		return sb->s_blocksize -
1267 			offsetof(struct ocfs2_dinode, id2.i_data.id_data) -
1268 			xattrsize;
1269 	else
1270 		return sb->s_blocksize -
1271 			offsetof(struct ocfs2_dinode, id2.i_data.id_data);
1272 }
1273 
1274 static inline int ocfs2_extent_recs_per_inode(struct super_block *sb)
1275 {
1276 	int size;
1277 
1278 	size = sb->s_blocksize -
1279 		offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1280 
1281 	return size / sizeof(struct ocfs2_extent_rec);
1282 }
1283 
1284 static inline int ocfs2_extent_recs_per_inode_with_xattr(
1285 						struct super_block *sb,
1286 						struct ocfs2_dinode *di)
1287 {
1288 	int size;
1289 	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
1290 
1291 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
1292 		size = sb->s_blocksize -
1293 			offsetof(struct ocfs2_dinode, id2.i_list.l_recs) -
1294 			xattrsize;
1295 	else
1296 		size = sb->s_blocksize -
1297 			offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1298 
1299 	return size / sizeof(struct ocfs2_extent_rec);
1300 }
1301 
1302 static inline int ocfs2_extent_recs_per_dx_root(struct super_block *sb)
1303 {
1304 	int size;
1305 
1306 	size = sb->s_blocksize -
1307 		offsetof(struct ocfs2_dx_root_block, dr_list.l_recs);
1308 
1309 	return size / sizeof(struct ocfs2_extent_rec);
1310 }
1311 
1312 static inline int ocfs2_chain_recs_per_inode(struct super_block *sb)
1313 {
1314 	int size;
1315 
1316 	size = sb->s_blocksize -
1317 		offsetof(struct ocfs2_dinode, id2.i_chain.cl_recs);
1318 
1319 	return size / sizeof(struct ocfs2_chain_rec);
1320 }
1321 
1322 static inline u16 ocfs2_extent_recs_per_eb(struct super_block *sb)
1323 {
1324 	int size;
1325 
1326 	size = sb->s_blocksize -
1327 		offsetof(struct ocfs2_extent_block, h_list.l_recs);
1328 
1329 	return size / sizeof(struct ocfs2_extent_rec);
1330 }
1331 
1332 static inline u16 ocfs2_extent_recs_per_gd(struct super_block *sb)
1333 {
1334 	int size;
1335 
1336 	size = sb->s_blocksize -
1337 		offsetof(struct ocfs2_group_desc, bg_list.l_recs);
1338 
1339 	return size / sizeof(struct ocfs2_extent_rec);
1340 }
1341 
1342 static inline int ocfs2_dx_entries_per_leaf(struct super_block *sb)
1343 {
1344 	int size;
1345 
1346 	size = sb->s_blocksize -
1347 		offsetof(struct ocfs2_dx_leaf, dl_list.de_entries);
1348 
1349 	return size / sizeof(struct ocfs2_dx_entry);
1350 }
1351 
1352 static inline int ocfs2_dx_entries_per_root(struct super_block *sb)
1353 {
1354 	int size;
1355 
1356 	size = sb->s_blocksize -
1357 		offsetof(struct ocfs2_dx_root_block, dr_entries.de_entries);
1358 
1359 	return size / sizeof(struct ocfs2_dx_entry);
1360 }
1361 
1362 static inline u16 ocfs2_local_alloc_size(struct super_block *sb)
1363 {
1364 	u16 size;
1365 
1366 	size = sb->s_blocksize -
1367 		offsetof(struct ocfs2_dinode, id2.i_lab.la_bitmap);
1368 
1369 	return size;
1370 }
1371 
1372 static inline int ocfs2_group_bitmap_size(struct super_block *sb,
1373 					  int suballocator,
1374 					  u32 feature_incompat)
1375 {
1376 	int size = sb->s_blocksize -
1377 		offsetof(struct ocfs2_group_desc, bg_bitmap);
1378 
1379 	/*
1380 	 * The cluster allocator uses the entire block.  Suballocators have
1381 	 * never used more than OCFS2_MAX_BG_BITMAP_SIZE.  Unfortunately, older
1382 	 * code expects bg_size set to the maximum.  Thus we must keep
1383 	 * bg_size as-is unless discontig_bg is enabled.
1384 	 */
1385 	if (suballocator &&
1386 	    (feature_incompat & OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG))
1387 		size = OCFS2_MAX_BG_BITMAP_SIZE;
1388 
1389 	return size;
1390 }
1391 
1392 static inline int ocfs2_truncate_recs_per_inode(struct super_block *sb)
1393 {
1394 	int size;
1395 
1396 	size = sb->s_blocksize -
1397 		offsetof(struct ocfs2_dinode, id2.i_dealloc.tl_recs);
1398 
1399 	return size / sizeof(struct ocfs2_truncate_rec);
1400 }
1401 
1402 static inline u64 ocfs2_backup_super_blkno(struct super_block *sb, int index)
1403 {
1404 	u64 offset = OCFS2_BACKUP_SB_START;
1405 
1406 	if (index >= 0 && index < OCFS2_MAX_BACKUP_SUPERBLOCKS) {
1407 		offset <<= (2 * index);
1408 		offset >>= sb->s_blocksize_bits;
1409 		return offset;
1410 	}
1411 
1412 	return 0;
1413 
1414 }
1415 
1416 static inline u16 ocfs2_xattr_recs_per_xb(struct super_block *sb)
1417 {
1418 	int size;
1419 
1420 	size = sb->s_blocksize -
1421 		offsetof(struct ocfs2_xattr_block,
1422 			 xb_attrs.xb_root.xt_list.l_recs);
1423 
1424 	return size / sizeof(struct ocfs2_extent_rec);
1425 }
1426 
1427 static inline u16 ocfs2_extent_recs_per_rb(struct super_block *sb)
1428 {
1429 	int size;
1430 
1431 	size = sb->s_blocksize -
1432 		offsetof(struct ocfs2_refcount_block, rf_list.l_recs);
1433 
1434 	return size / sizeof(struct ocfs2_extent_rec);
1435 }
1436 
1437 static inline u16 ocfs2_refcount_recs_per_rb(struct super_block *sb)
1438 {
1439 	int size;
1440 
1441 	size = sb->s_blocksize -
1442 		offsetof(struct ocfs2_refcount_block, rf_records.rl_recs);
1443 
1444 	return size / sizeof(struct ocfs2_refcount_rec);
1445 }
1446 
1447 static inline u32
1448 ocfs2_get_ref_rec_low_cpos(const struct ocfs2_refcount_rec *rec)
1449 {
1450 	return le64_to_cpu(rec->r_cpos) & OCFS2_32BIT_POS_MASK;
1451 }
1452 #else
1453 static inline int ocfs2_fast_symlink_chars(int blocksize)
1454 {
1455 	return blocksize - offsetof(struct ocfs2_dinode, id2.i_symlink);
1456 }
1457 
1458 static inline int ocfs2_max_inline_data_with_xattr(int blocksize,
1459 						   struct ocfs2_dinode *di)
1460 {
1461 	if (di && (di->i_dyn_features & OCFS2_INLINE_XATTR_FL))
1462 		return blocksize -
1463 			offsetof(struct ocfs2_dinode, id2.i_data.id_data) -
1464 			di->i_xattr_inline_size;
1465 	else
1466 		return blocksize -
1467 			offsetof(struct ocfs2_dinode, id2.i_data.id_data);
1468 }
1469 
1470 static inline int ocfs2_extent_recs_per_inode(int blocksize)
1471 {
1472 	int size;
1473 
1474 	size = blocksize -
1475 		offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1476 
1477 	return size / sizeof(struct ocfs2_extent_rec);
1478 }
1479 
1480 static inline int ocfs2_chain_recs_per_inode(int blocksize)
1481 {
1482 	int size;
1483 
1484 	size = blocksize -
1485 		offsetof(struct ocfs2_dinode, id2.i_chain.cl_recs);
1486 
1487 	return size / sizeof(struct ocfs2_chain_rec);
1488 }
1489 
1490 static inline int ocfs2_extent_recs_per_eb(int blocksize)
1491 {
1492 	int size;
1493 
1494 	size = blocksize -
1495 		offsetof(struct ocfs2_extent_block, h_list.l_recs);
1496 
1497 	return size / sizeof(struct ocfs2_extent_rec);
1498 }
1499 
1500 static inline int ocfs2_extent_recs_per_gd(int blocksize)
1501 {
1502 	int size;
1503 
1504 	size = blocksize -
1505 		offsetof(struct ocfs2_group_desc, bg_list.l_recs);
1506 
1507 	return size / sizeof(struct ocfs2_extent_rec);
1508 }
1509 
1510 static inline int ocfs2_local_alloc_size(int blocksize)
1511 {
1512 	int size;
1513 
1514 	size = blocksize -
1515 		offsetof(struct ocfs2_dinode, id2.i_lab.la_bitmap);
1516 
1517 	return size;
1518 }
1519 
1520 static inline int ocfs2_group_bitmap_size(int blocksize,
1521 					  int suballocator,
1522 					  uint32_t feature_incompat)
1523 {
1524 	int size = sb->s_blocksize -
1525 		offsetof(struct ocfs2_group_desc, bg_bitmap);
1526 
1527 	/*
1528 	 * The cluster allocator uses the entire block.  Suballocators have
1529 	 * never used more than OCFS2_MAX_BG_BITMAP_SIZE.  Unfortunately, older
1530 	 * code expects bg_size set to the maximum.  Thus we must keep
1531 	 * bg_size as-is unless discontig_bg is enabled.
1532 	 */
1533 	if (suballocator &&
1534 	    (feature_incompat & OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG))
1535 		size = OCFS2_MAX_BG_BITMAP_SIZE;
1536 
1537 	return size;
1538 }
1539 
1540 static inline int ocfs2_truncate_recs_per_inode(int blocksize)
1541 {
1542 	int size;
1543 
1544 	size = blocksize -
1545 		offsetof(struct ocfs2_dinode, id2.i_dealloc.tl_recs);
1546 
1547 	return size / sizeof(struct ocfs2_truncate_rec);
1548 }
1549 
1550 static inline uint64_t ocfs2_backup_super_blkno(int blocksize, int index)
1551 {
1552 	uint64_t offset = OCFS2_BACKUP_SB_START;
1553 
1554 	if (index >= 0 && index < OCFS2_MAX_BACKUP_SUPERBLOCKS) {
1555 		offset <<= (2 * index);
1556 		offset /= blocksize;
1557 		return offset;
1558 	}
1559 
1560 	return 0;
1561 }
1562 
1563 static inline int ocfs2_xattr_recs_per_xb(int blocksize)
1564 {
1565 	int size;
1566 
1567 	size = blocksize -
1568 		offsetof(struct ocfs2_xattr_block,
1569 			 xb_attrs.xb_root.xt_list.l_recs);
1570 
1571 	return size / sizeof(struct ocfs2_extent_rec);
1572 }
1573 #endif  /* __KERNEL__ */
1574 
1575 
1576 static inline int ocfs2_system_inode_is_global(int type)
1577 {
1578 	return ((type >= 0) &&
1579 		(type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE));
1580 }
1581 
1582 static inline int ocfs2_sprintf_system_inode_name(char *buf, int len,
1583 						  int type, int slot)
1584 {
1585 	int chars;
1586 
1587         /*
1588          * Global system inodes can only have one copy.  Everything
1589          * after OCFS2_LAST_GLOBAL_SYSTEM_INODE in the system inode
1590          * list has a copy per slot.
1591          */
1592 	if (type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE)
1593 		chars = snprintf(buf, len, "%s",
1594 				 ocfs2_system_inodes[type].si_name);
1595 	else
1596 		chars = snprintf(buf, len,
1597 				 ocfs2_system_inodes[type].si_name,
1598 				 slot);
1599 
1600 	return chars;
1601 }
1602 
1603 static inline void ocfs2_set_de_type(struct ocfs2_dir_entry *de,
1604 				    umode_t mode)
1605 {
1606 	de->file_type = fs_umode_to_ftype(mode);
1607 }
1608 
1609 static inline int ocfs2_gd_is_discontig(struct ocfs2_group_desc *gd)
1610 {
1611 	if ((offsetof(struct ocfs2_group_desc, bg_bitmap) +
1612 	     le16_to_cpu(gd->bg_size)) !=
1613 	    offsetof(struct ocfs2_group_desc, bg_list))
1614 		return 0;
1615 	/*
1616 	 * Only valid to check l_next_free_rec if
1617 	 * bg_bitmap + bg_size == bg_list.
1618 	 */
1619 	if (!gd->bg_list.l_next_free_rec)
1620 		return 0;
1621 	return 1;
1622 }
1623 #endif  /* _OCFS2_FS_H */
1624 
1625