xref: /linux/fs/ocfs2/ocfs2_fs.h (revision d4b996f9ef1fe83d9ce9ad5c1ca0bd8231638ce5)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * ocfs2_fs.h
4  *
5  * On-disk structures for OCFS2.
6  *
7  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
8  */
9 
10 #ifndef _OCFS2_FS_H
11 #define _OCFS2_FS_H
12 
13 #include <linux/magic.h>
14 
15 /* Version */
16 #define OCFS2_MAJOR_REV_LEVEL		0
17 #define OCFS2_MINOR_REV_LEVEL          	90
18 
19 /*
20  * An OCFS2 volume starts this way:
21  * Sector 0: Valid ocfs1_vol_disk_hdr that cleanly fails to mount OCFS.
22  * Sector 1: Valid ocfs1_vol_label that cleanly fails to mount OCFS.
23  * Block OCFS2_SUPER_BLOCK_BLKNO: OCFS2 superblock.
24  *
25  * All other structures are found from the superblock information.
26  *
27  * OCFS2_SUPER_BLOCK_BLKNO is in blocks, not sectors.  eg, for a
28  * blocksize of 2K, it is 4096 bytes into disk.
29  */
30 #define OCFS2_SUPER_BLOCK_BLKNO		2
31 
32 /*
33  * Cluster size limits. The maximum is kept arbitrarily at 1 MB, and could
34  * grow if needed.
35  */
36 #define OCFS2_MIN_CLUSTERSIZE		4096
37 #define OCFS2_MAX_CLUSTERSIZE		1048576
38 
39 /*
40  * Blocks cannot be bigger than clusters, so the maximum blocksize is the
41  * minimum cluster size.
42  */
43 #define OCFS2_MIN_BLOCKSIZE		512
44 #define OCFS2_MAX_BLOCKSIZE		OCFS2_MIN_CLUSTERSIZE
45 
46 /* Object signatures */
47 #define OCFS2_SUPER_BLOCK_SIGNATURE	"OCFSV2"
48 #define OCFS2_INODE_SIGNATURE		"INODE01"
49 #define OCFS2_EXTENT_BLOCK_SIGNATURE	"EXBLK01"
50 #define OCFS2_GROUP_DESC_SIGNATURE      "GROUP01"
51 #define OCFS2_XATTR_BLOCK_SIGNATURE	"XATTR01"
52 #define OCFS2_DIR_TRAILER_SIGNATURE	"DIRTRL1"
53 #define OCFS2_DX_ROOT_SIGNATURE		"DXDIR01"
54 #define OCFS2_DX_LEAF_SIGNATURE		"DXLEAF1"
55 #define OCFS2_REFCOUNT_BLOCK_SIGNATURE	"REFCNT1"
56 
57 /* Compatibility flags */
58 #define OCFS2_HAS_COMPAT_FEATURE(sb,mask)			\
59 	( OCFS2_SB(sb)->s_feature_compat & (mask) )
60 #define OCFS2_HAS_RO_COMPAT_FEATURE(sb,mask)			\
61 	( OCFS2_SB(sb)->s_feature_ro_compat & (mask) )
62 #define OCFS2_HAS_INCOMPAT_FEATURE(sb,mask)			\
63 	( OCFS2_SB(sb)->s_feature_incompat & (mask) )
64 #define OCFS2_SET_COMPAT_FEATURE(sb,mask)			\
65 	OCFS2_SB(sb)->s_feature_compat |= (mask)
66 #define OCFS2_SET_RO_COMPAT_FEATURE(sb,mask)			\
67 	OCFS2_SB(sb)->s_feature_ro_compat |= (mask)
68 #define OCFS2_SET_INCOMPAT_FEATURE(sb,mask)			\
69 	OCFS2_SB(sb)->s_feature_incompat |= (mask)
70 #define OCFS2_CLEAR_COMPAT_FEATURE(sb,mask)			\
71 	OCFS2_SB(sb)->s_feature_compat &= ~(mask)
72 #define OCFS2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\
73 	OCFS2_SB(sb)->s_feature_ro_compat &= ~(mask)
74 #define OCFS2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\
75 	OCFS2_SB(sb)->s_feature_incompat &= ~(mask)
76 
77 #define OCFS2_FEATURE_COMPAT_SUPP	(OCFS2_FEATURE_COMPAT_BACKUP_SB	\
78 					 | OCFS2_FEATURE_COMPAT_JBD2_SB)
79 #define OCFS2_FEATURE_INCOMPAT_SUPP	(OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT \
80 					 | OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC \
81 					 | OCFS2_FEATURE_INCOMPAT_INLINE_DATA \
82 					 | OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP \
83 					 | OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK \
84 					 | OCFS2_FEATURE_INCOMPAT_XATTR \
85 					 | OCFS2_FEATURE_INCOMPAT_META_ECC \
86 					 | OCFS2_FEATURE_INCOMPAT_INDEXED_DIRS \
87 					 | OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE \
88 					 | OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG	\
89 					 | OCFS2_FEATURE_INCOMPAT_CLUSTERINFO \
90 					 | OCFS2_FEATURE_INCOMPAT_APPEND_DIO)
91 #define OCFS2_FEATURE_RO_COMPAT_SUPP	(OCFS2_FEATURE_RO_COMPAT_UNWRITTEN \
92 					 | OCFS2_FEATURE_RO_COMPAT_USRQUOTA \
93 					 | OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)
94 
95 /*
96  * Heartbeat-only devices are missing journals and other files.  The
97  * filesystem driver can't load them, but the library can.  Never put
98  * this in OCFS2_FEATURE_INCOMPAT_SUPP, *ever*.
99  */
100 #define OCFS2_FEATURE_INCOMPAT_HEARTBEAT_DEV	0x0002
101 
102 /*
103  * tunefs sets this incompat flag before starting the resize and clears it
104  * at the end. This flag protects users from inadvertently mounting the fs
105  * after an aborted run without fsck-ing.
106  */
107 #define OCFS2_FEATURE_INCOMPAT_RESIZE_INPROG    0x0004
108 
109 /* Used to denote a non-clustered volume */
110 #define OCFS2_FEATURE_INCOMPAT_LOCAL_MOUNT	0x0008
111 
112 /* Support for sparse allocation in b-trees */
113 #define OCFS2_FEATURE_INCOMPAT_SPARSE_ALLOC	0x0010
114 
115 /*
116  * Tunefs sets this incompat flag before starting an operation which
117  * would require cleanup on abort. This is done to protect users from
118  * inadvertently mounting the fs after an aborted run without
119  * fsck-ing.
120  *
121  * s_tunefs_flags on the super block describes precisely which
122  * operations were in progress.
123  */
124 #define OCFS2_FEATURE_INCOMPAT_TUNEFS_INPROG	0x0020
125 
126 /* Support for data packed into inode blocks */
127 #define OCFS2_FEATURE_INCOMPAT_INLINE_DATA	0x0040
128 
129 /*
130  * Support for alternate, userspace cluster stacks.  If set, the superblock
131  * field s_cluster_info contains a tag for the alternate stack in use as
132  * well as the name of the cluster being joined.
133  * mount.ocfs2 must pass in a matching stack name.
134  *
135  * If not set, the classic stack will be used.  This is compatbile with
136  * all older versions.
137  */
138 #define OCFS2_FEATURE_INCOMPAT_USERSPACE_STACK	0x0080
139 
140 /* Support for the extended slot map */
141 #define OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP 0x100
142 
143 /* Support for extended attributes */
144 #define OCFS2_FEATURE_INCOMPAT_XATTR		0x0200
145 
146 /* Support for indexed directores */
147 #define OCFS2_FEATURE_INCOMPAT_INDEXED_DIRS	0x0400
148 
149 /* Metadata checksum and error correction */
150 #define OCFS2_FEATURE_INCOMPAT_META_ECC		0x0800
151 
152 /* Refcount tree support */
153 #define OCFS2_FEATURE_INCOMPAT_REFCOUNT_TREE	0x1000
154 
155 /* Discontiguous block groups */
156 #define OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG	0x2000
157 
158 /*
159  * Incompat bit to indicate useable clusterinfo with stackflags for all
160  * cluster stacks (userspace adnd o2cb). If this bit is set,
161  * INCOMPAT_USERSPACE_STACK becomes superfluous and thus should not be set.
162  */
163 #define OCFS2_FEATURE_INCOMPAT_CLUSTERINFO	0x4000
164 
165 /*
166  * Append Direct IO support
167  */
168 #define OCFS2_FEATURE_INCOMPAT_APPEND_DIO	0x8000
169 
170 /*
171  * backup superblock flag is used to indicate that this volume
172  * has backup superblocks.
173  */
174 #define OCFS2_FEATURE_COMPAT_BACKUP_SB		0x0001
175 
176 /*
177  * The filesystem will correctly handle journal feature bits.
178  */
179 #define OCFS2_FEATURE_COMPAT_JBD2_SB		0x0002
180 
181 /*
182  * Unwritten extents support.
183  */
184 #define OCFS2_FEATURE_RO_COMPAT_UNWRITTEN	0x0001
185 
186 /*
187  * Maintain quota information for this filesystem
188  */
189 #define OCFS2_FEATURE_RO_COMPAT_USRQUOTA	0x0002
190 #define OCFS2_FEATURE_RO_COMPAT_GRPQUOTA	0x0004
191 
192 
193 /* The byte offset of the first backup block will be 1G.
194  * The following will be 4G, 16G, 64G, 256G and 1T.
195  */
196 #define OCFS2_BACKUP_SB_START			1 << 30
197 
198 /* the max backup superblock nums */
199 #define OCFS2_MAX_BACKUP_SUPERBLOCKS	6
200 
201 /*
202  * Flags on ocfs2_super_block.s_tunefs_flags
203  */
204 #define OCFS2_TUNEFS_INPROG_REMOVE_SLOT		0x0001	/* Removing slots */
205 
206 /*
207  * Flags on ocfs2_dinode.i_flags
208  */
209 #define OCFS2_VALID_FL		(0x00000001)	/* Inode is valid */
210 #define OCFS2_UNUSED2_FL	(0x00000002)
211 #define OCFS2_ORPHANED_FL	(0x00000004)	/* On the orphan list */
212 #define OCFS2_UNUSED3_FL	(0x00000008)
213 /* System inode flags */
214 #define OCFS2_SYSTEM_FL		(0x00000010)	/* System inode */
215 #define OCFS2_SUPER_BLOCK_FL	(0x00000020)	/* Super block */
216 #define OCFS2_LOCAL_ALLOC_FL	(0x00000040)	/* Slot local alloc bitmap */
217 #define OCFS2_BITMAP_FL		(0x00000080)	/* Allocation bitmap */
218 #define OCFS2_JOURNAL_FL	(0x00000100)	/* Slot local journal */
219 #define OCFS2_HEARTBEAT_FL	(0x00000200)	/* Heartbeat area */
220 #define OCFS2_CHAIN_FL		(0x00000400)	/* Chain allocator */
221 #define OCFS2_DEALLOC_FL	(0x00000800)	/* Truncate log */
222 #define OCFS2_QUOTA_FL		(0x00001000)	/* Quota file */
223 #define OCFS2_DIO_ORPHANED_FL	(0X00002000)	/* On the orphan list especially
224 						 * for dio */
225 
226 /*
227  * Flags on ocfs2_dinode.i_dyn_features
228  *
229  * These can change much more often than i_flags. When adding flags,
230  * keep in mind that i_dyn_features is only 16 bits wide.
231  */
232 #define OCFS2_INLINE_DATA_FL	(0x0001)	/* Data stored in inode block */
233 #define OCFS2_HAS_XATTR_FL	(0x0002)
234 #define OCFS2_INLINE_XATTR_FL	(0x0004)
235 #define OCFS2_INDEXED_DIR_FL	(0x0008)
236 #define OCFS2_HAS_REFCOUNT_FL   (0x0010)
237 
238 /* Inode attributes, keep in sync with EXT2 */
239 #define OCFS2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */
240 #define OCFS2_UNRM_FL			FS_UNRM_FL	/* Undelete */
241 #define OCFS2_COMPR_FL			FS_COMPR_FL	/* Compress file */
242 #define OCFS2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */
243 #define OCFS2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */
244 #define OCFS2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */
245 #define OCFS2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */
246 #define OCFS2_NOATIME_FL		FS_NOATIME_FL	/* do not update atime */
247 /* Reserved for compression usage... */
248 #define OCFS2_DIRTY_FL			FS_DIRTY_FL
249 #define OCFS2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */
250 #define OCFS2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */
251 #define OCFS2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */
252 /* End compression flags --- maybe not all used */
253 #define OCFS2_BTREE_FL			FS_BTREE_FL	/* btree format dir */
254 #define OCFS2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */
255 #define OCFS2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */
256 #define OCFS2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */
257 #define OCFS2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */
258 #define OCFS2_DIRSYNC_FL		FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */
259 #define OCFS2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/
260 #define OCFS2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */
261 
262 #define OCFS2_FL_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */
263 #define OCFS2_FL_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */
264 
265 /*
266  * Extent record flags (e_node.leaf.flags)
267  */
268 #define OCFS2_EXT_UNWRITTEN		(0x01)	/* Extent is allocated but
269 						 * unwritten */
270 #define OCFS2_EXT_REFCOUNTED		(0x02)  /* Extent is reference
271 						 * counted in an associated
272 						 * refcount tree */
273 
274 /*
275  * Journal Flags (ocfs2_dinode.id1.journal1.i_flags)
276  */
277 #define OCFS2_JOURNAL_DIRTY_FL	(0x00000001)	/* Journal needs recovery */
278 
279 /*
280  * superblock s_state flags
281  */
282 #define OCFS2_ERROR_FS		(0x00000001)	/* FS saw errors */
283 
284 /* Limit of space in ocfs2_dir_entry */
285 #define OCFS2_MAX_FILENAME_LEN		255
286 
287 /* Maximum slots on an ocfs2 file system */
288 #define OCFS2_MAX_SLOTS			255
289 
290 /* Slot map indicator for an empty slot */
291 #define OCFS2_INVALID_SLOT		((u16)-1)
292 
293 #define OCFS2_VOL_UUID_LEN		16
294 #define OCFS2_MAX_VOL_LABEL_LEN		64
295 
296 /* The cluster stack fields */
297 #define OCFS2_STACK_LABEL_LEN		4
298 #define OCFS2_CLUSTER_NAME_LEN		16
299 
300 /* Classic (historically speaking) cluster stack */
301 #define OCFS2_CLASSIC_CLUSTER_STACK	"o2cb"
302 
303 /* Journal limits (in bytes) */
304 #define OCFS2_MIN_JOURNAL_SIZE		(4 * 1024 * 1024)
305 
306 /*
307  * Inline extended attribute size (in bytes)
308  * The value chosen should be aligned to 16 byte boundaries.
309  */
310 #define OCFS2_MIN_XATTR_INLINE_SIZE     256
311 
312 /*
313  * Cluster info flags (ocfs2_cluster_info.ci_stackflags)
314  */
315 #define OCFS2_CLUSTER_O2CB_GLOBAL_HEARTBEAT	(0x01)
316 
317 struct ocfs2_system_inode_info {
318 	char	*si_name;
319 	int	si_iflags;
320 	int	si_mode;
321 };
322 
323 /* System file index */
324 enum {
325 	BAD_BLOCK_SYSTEM_INODE = 0,
326 	GLOBAL_INODE_ALLOC_SYSTEM_INODE,
327 #define OCFS2_FIRST_ONLINE_SYSTEM_INODE GLOBAL_INODE_ALLOC_SYSTEM_INODE
328 	SLOT_MAP_SYSTEM_INODE,
329 	HEARTBEAT_SYSTEM_INODE,
330 	GLOBAL_BITMAP_SYSTEM_INODE,
331 	USER_QUOTA_SYSTEM_INODE,
332 	GROUP_QUOTA_SYSTEM_INODE,
333 #define OCFS2_LAST_GLOBAL_SYSTEM_INODE GROUP_QUOTA_SYSTEM_INODE
334 #define OCFS2_FIRST_LOCAL_SYSTEM_INODE ORPHAN_DIR_SYSTEM_INODE
335 	ORPHAN_DIR_SYSTEM_INODE,
336 	EXTENT_ALLOC_SYSTEM_INODE,
337 	INODE_ALLOC_SYSTEM_INODE,
338 	JOURNAL_SYSTEM_INODE,
339 	LOCAL_ALLOC_SYSTEM_INODE,
340 	TRUNCATE_LOG_SYSTEM_INODE,
341 	LOCAL_USER_QUOTA_SYSTEM_INODE,
342 	LOCAL_GROUP_QUOTA_SYSTEM_INODE,
343 #define OCFS2_LAST_LOCAL_SYSTEM_INODE LOCAL_GROUP_QUOTA_SYSTEM_INODE
344 	NUM_SYSTEM_INODES
345 };
346 #define NUM_GLOBAL_SYSTEM_INODES OCFS2_FIRST_LOCAL_SYSTEM_INODE
347 #define NUM_LOCAL_SYSTEM_INODES	\
348 		(NUM_SYSTEM_INODES - OCFS2_FIRST_LOCAL_SYSTEM_INODE)
349 
350 static struct ocfs2_system_inode_info ocfs2_system_inodes[NUM_SYSTEM_INODES] = {
351 	/* Global system inodes (single copy) */
352 	/* The first two are only used from userspace mfks/tunefs */
353 	[BAD_BLOCK_SYSTEM_INODE]		= { "bad_blocks", 0, S_IFREG | 0644 },
354 	[GLOBAL_INODE_ALLOC_SYSTEM_INODE] 	= { "global_inode_alloc", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
355 
356 	/* These are used by the running filesystem */
357 	[SLOT_MAP_SYSTEM_INODE]			= { "slot_map", 0, S_IFREG | 0644 },
358 	[HEARTBEAT_SYSTEM_INODE]		= { "heartbeat", OCFS2_HEARTBEAT_FL, S_IFREG | 0644 },
359 	[GLOBAL_BITMAP_SYSTEM_INODE]		= { "global_bitmap", 0, S_IFREG | 0644 },
360 	[USER_QUOTA_SYSTEM_INODE]		= { "aquota.user", OCFS2_QUOTA_FL, S_IFREG | 0644 },
361 	[GROUP_QUOTA_SYSTEM_INODE]		= { "aquota.group", OCFS2_QUOTA_FL, S_IFREG | 0644 },
362 
363 	/* Slot-specific system inodes (one copy per slot) */
364 	[ORPHAN_DIR_SYSTEM_INODE]		= { "orphan_dir:%04d", 0, S_IFDIR | 0755 },
365 	[EXTENT_ALLOC_SYSTEM_INODE]		= { "extent_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
366 	[INODE_ALLOC_SYSTEM_INODE]		= { "inode_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_CHAIN_FL, S_IFREG | 0644 },
367 	[JOURNAL_SYSTEM_INODE]			= { "journal:%04d", OCFS2_JOURNAL_FL, S_IFREG | 0644 },
368 	[LOCAL_ALLOC_SYSTEM_INODE]		= { "local_alloc:%04d", OCFS2_BITMAP_FL | OCFS2_LOCAL_ALLOC_FL, S_IFREG | 0644 },
369 	[TRUNCATE_LOG_SYSTEM_INODE]		= { "truncate_log:%04d", OCFS2_DEALLOC_FL, S_IFREG | 0644 },
370 	[LOCAL_USER_QUOTA_SYSTEM_INODE]		= { "aquota.user:%04d", OCFS2_QUOTA_FL, S_IFREG | 0644 },
371 	[LOCAL_GROUP_QUOTA_SYSTEM_INODE]	= { "aquota.group:%04d", OCFS2_QUOTA_FL, S_IFREG | 0644 },
372 };
373 
374 /* Parameter passed from mount.ocfs2 to module */
375 #define OCFS2_HB_NONE			"heartbeat=none"
376 #define OCFS2_HB_LOCAL			"heartbeat=local"
377 #define OCFS2_HB_GLOBAL			"heartbeat=global"
378 
379 /*
380  * OCFS2_DIR_PAD defines the directory entries boundaries
381  *
382  * NOTE: It must be a multiple of 4
383  */
384 #define OCFS2_DIR_PAD			4
385 #define OCFS2_DIR_ROUND			(OCFS2_DIR_PAD - 1)
386 #define OCFS2_DIR_MEMBER_LEN 		offsetof(struct ocfs2_dir_entry, name)
387 #define OCFS2_DIR_REC_LEN(name_len)	(((name_len) + OCFS2_DIR_MEMBER_LEN + \
388                                           OCFS2_DIR_ROUND) & \
389 					 ~OCFS2_DIR_ROUND)
390 #define OCFS2_DIR_MIN_REC_LEN	OCFS2_DIR_REC_LEN(1)
391 
392 #define OCFS2_LINK_MAX		32000
393 #define	OCFS2_DX_LINK_MAX	((1U << 31) - 1U)
394 #define	OCFS2_LINKS_HI_SHIFT	16
395 #define	OCFS2_DX_ENTRIES_MAX	(0xffffffffU)
396 
397 
398 /*
399  * Convenience casts
400  */
401 #define OCFS2_RAW_SB(dinode)		(&((dinode)->id2.i_super))
402 
403 /*
404  * Block checking structure.  This is used in metadata to validate the
405  * contents.  If OCFS2_FEATURE_INCOMPAT_META_ECC is not set, it is all
406  * zeros.
407  */
408 struct ocfs2_block_check {
409 /*00*/	__le32 bc_crc32e;	/* 802.3 Ethernet II CRC32 */
410 	__le16 bc_ecc;		/* Single-error-correction parity vector.
411 				   This is a simple Hamming code dependent
412 				   on the blocksize.  OCFS2's maximum
413 				   blocksize, 4K, requires 16 parity bits,
414 				   so we fit in __le16. */
415 	__le16 bc_reserved1;
416 /*08*/
417 };
418 
419 /*
420  * On disk extent record for OCFS2
421  * It describes a range of clusters on disk.
422  *
423  * Length fields are divided into interior and leaf node versions.
424  * This leaves room for a flags field (OCFS2_EXT_*) in the leaf nodes.
425  */
426 struct ocfs2_extent_rec {
427 /*00*/	__le32 e_cpos;		/* Offset into the file, in clusters */
428 	union {
429 		__le32 e_int_clusters; /* Clusters covered by all children */
430 		struct {
431 			__le16 e_leaf_clusters; /* Clusters covered by this
432 						   extent */
433 			__u8 e_reserved1;
434 			__u8 e_flags; /* Extent flags */
435 		};
436 	};
437 	__le64 e_blkno;		/* Physical disk offset, in blocks */
438 /*10*/
439 };
440 
441 struct ocfs2_chain_rec {
442 	__le32 c_free;	/* Number of free bits in this chain. */
443 	__le32 c_total;	/* Number of total bits in this chain */
444 	__le64 c_blkno;	/* Physical disk offset (blocks) of 1st group */
445 };
446 
447 struct ocfs2_truncate_rec {
448 	__le32 t_start;		/* 1st cluster in this log */
449 	__le32 t_clusters;	/* Number of total clusters covered */
450 };
451 
452 /*
453  * On disk extent list for OCFS2 (node in the tree).  Note that this
454  * is contained inside ocfs2_dinode or ocfs2_extent_block, so the
455  * offsets are relative to ocfs2_dinode.id2.i_list or
456  * ocfs2_extent_block.h_list, respectively.
457  */
458 struct ocfs2_extent_list {
459 /*00*/	__le16 l_tree_depth;		/* Extent tree depth from this
460 					   point.  0 means data extents
461 					   hang directly off this
462 					   header (a leaf)
463 					   NOTE: The high 8 bits cannot be
464 					   used - tree_depth is never that big.
465 					*/
466 	__le16 l_count;			/* Number of extent records */
467 	__le16 l_next_free_rec;		/* Next unused extent slot */
468 	__le16 l_reserved1;
469 	__le64 l_reserved2;		/* Pad to
470 					   sizeof(ocfs2_extent_rec) */
471 /*10*/	struct ocfs2_extent_rec l_recs[];	/* Extent records */
472 };
473 
474 /*
475  * On disk allocation chain list for OCFS2.  Note that this is
476  * contained inside ocfs2_dinode, so the offsets are relative to
477  * ocfs2_dinode.id2.i_chain.
478  */
479 struct ocfs2_chain_list {
480 /*00*/	__le16 cl_cpg;			/* Clusters per Block Group */
481 	__le16 cl_bpc;			/* Bits per cluster */
482 	__le16 cl_count;		/* Total chains in this list */
483 	__le16 cl_next_free_rec;	/* Next unused chain slot */
484 	__le64 cl_reserved1;
485 /*10*/	struct ocfs2_chain_rec cl_recs[];	/* Chain records */
486 };
487 
488 /*
489  * On disk deallocation log for OCFS2.  Note that this is
490  * contained inside ocfs2_dinode, so the offsets are relative to
491  * ocfs2_dinode.id2.i_dealloc.
492  */
493 struct ocfs2_truncate_log {
494 /*00*/	__le16 tl_count;		/* Total records in this log */
495 	__le16 tl_used;			/* Number of records in use */
496 	__le32 tl_reserved1;
497 /*08*/	struct ocfs2_truncate_rec tl_recs[];	/* Truncate records */
498 };
499 
500 /*
501  * On disk extent block (indirect block) for OCFS2
502  */
503 struct ocfs2_extent_block
504 {
505 /*00*/	__u8 h_signature[8];		/* Signature for verification */
506 	struct ocfs2_block_check h_check;	/* Error checking */
507 /*10*/	__le16 h_suballoc_slot;		/* Slot suballocator this
508 					   extent_header belongs to */
509 	__le16 h_suballoc_bit;		/* Bit offset in suballocator
510 					   block group */
511 	__le32 h_fs_generation;		/* Must match super block */
512 	__le64 h_blkno;			/* Offset on disk, in blocks */
513 /*20*/	__le64 h_suballoc_loc;		/* Suballocator block group this
514 					   eb belongs to.  Only valid
515 					   if allocated from a
516 					   discontiguous block group */
517 	__le64 h_next_leaf_blk;		/* Offset on disk, in blocks,
518 					   of next leaf header pointing
519 					   to data */
520 /*30*/	struct ocfs2_extent_list h_list;	/* Extent record list */
521 /* Actual on-disk size is one block */
522 };
523 
524 /*
525  * On disk slot map for OCFS2.  This defines the contents of the "slot_map"
526  * system file.  A slot is valid if it contains a node number >= 0.  The
527  * value -1 (0xFFFF) is OCFS2_INVALID_SLOT.  This marks a slot empty.
528  */
529 struct ocfs2_slot_map {
530 /*00*/	__le16 sm_slots[0];
531 /*
532  * Actual on-disk size is one block.  OCFS2_MAX_SLOTS is 255,
533  * 255 * sizeof(__le16) == 512B, within the 512B block minimum blocksize.
534  */
535 };
536 
537 struct ocfs2_extended_slot {
538 /*00*/	__u8	es_valid;
539 	__u8	es_reserved1[3];
540 	__le32	es_node_num;
541 /*08*/
542 };
543 
544 /*
545  * The extended slot map, used when OCFS2_FEATURE_INCOMPAT_EXTENDED_SLOT_MAP
546  * is set.  It separates out the valid marker from the node number, and
547  * has room to grow.  Unlike the old slot map, this format is defined by
548  * i_size.
549  */
550 struct ocfs2_slot_map_extended {
551 /*00*/	struct ocfs2_extended_slot se_slots[0];
552 /*
553  * Actual size is i_size of the slot_map system file.  It should
554  * match s_max_slots * sizeof(struct ocfs2_extended_slot)
555  */
556 };
557 
558 /*
559  * ci_stackflags is only valid if the incompat bit
560  * OCFS2_FEATURE_INCOMPAT_CLUSTERINFO is set.
561  */
562 struct ocfs2_cluster_info {
563 /*00*/	__u8   ci_stack[OCFS2_STACK_LABEL_LEN];
564 	union {
565 		__le32 ci_reserved;
566 		struct {
567 			__u8 ci_stackflags;
568 			__u8 ci_reserved1;
569 			__u8 ci_reserved2;
570 			__u8 ci_reserved3;
571 		};
572 	};
573 /*08*/	__u8   ci_cluster[OCFS2_CLUSTER_NAME_LEN];
574 /*18*/
575 };
576 
577 /*
578  * On disk superblock for OCFS2
579  * Note that it is contained inside an ocfs2_dinode, so all offsets
580  * are relative to the start of ocfs2_dinode.id2.
581  */
582 struct ocfs2_super_block {
583 /*00*/	__le16 s_major_rev_level;
584 	__le16 s_minor_rev_level;
585 	__le16 s_mnt_count;
586 	__le16 s_max_mnt_count;
587 	__le16 s_state;			/* File system state */
588 	__le16 s_errors;			/* Behaviour when detecting errors */
589 	__le32 s_checkinterval;		/* Max time between checks */
590 /*10*/	__le64 s_lastcheck;		/* Time of last check */
591 	__le32 s_creator_os;		/* OS */
592 	__le32 s_feature_compat;		/* Compatible feature set */
593 /*20*/	__le32 s_feature_incompat;	/* Incompatible feature set */
594 	__le32 s_feature_ro_compat;	/* Readonly-compatible feature set */
595 	__le64 s_root_blkno;		/* Offset, in blocks, of root directory
596 					   dinode */
597 /*30*/	__le64 s_system_dir_blkno;	/* Offset, in blocks, of system
598 					   directory dinode */
599 	__le32 s_blocksize_bits;		/* Blocksize for this fs */
600 	__le32 s_clustersize_bits;	/* Clustersize for this fs */
601 /*40*/	__le16 s_max_slots;		/* Max number of simultaneous mounts
602 					   before tunefs required */
603 	__le16 s_tunefs_flag;
604 	__le32 s_uuid_hash;		/* hash value of uuid */
605 	__le64 s_first_cluster_group;	/* Block offset of 1st cluster
606 					 * group header */
607 /*50*/	__u8  s_label[OCFS2_MAX_VOL_LABEL_LEN];	/* Label for mounting, etc. */
608 /*90*/	__u8  s_uuid[OCFS2_VOL_UUID_LEN];	/* 128-bit uuid */
609 /*A0*/  struct ocfs2_cluster_info s_cluster_info; /* Only valid if either
610 						     userspace or clusterinfo
611 						     INCOMPAT flag set. */
612 /*B8*/	__le16 s_xattr_inline_size;	/* extended attribute inline size
613 					   for this fs*/
614 	__le16 s_reserved0;
615 	__le32 s_dx_seed[3];		/* seed[0-2] for dx dir hash.
616 					 * s_uuid_hash serves as seed[3]. */
617 /*C0*/  __le64 s_reserved2[15];		/* Fill out superblock */
618 /*140*/
619 
620 	/*
621 	 * NOTE: As stated above, all offsets are relative to
622 	 * ocfs2_dinode.id2, which is at 0xC0 in the inode.
623 	 * 0xC0 + 0x140 = 0x200 or 512 bytes.  A superblock must fit within
624 	 * our smallest blocksize, which is 512 bytes.  To ensure this,
625 	 * we reserve the space in s_reserved2.  Anything past s_reserved2
626 	 * will not be available on the smallest blocksize.
627 	 */
628 };
629 
630 /*
631  * Local allocation bitmap for OCFS2 slots
632  * Note that it exists inside an ocfs2_dinode, so all offsets are
633  * relative to the start of ocfs2_dinode.id2.
634  */
635 struct ocfs2_local_alloc
636 {
637 /*00*/	__le32 la_bm_off;	/* Starting bit offset in main bitmap */
638 	__le16 la_size;		/* Size of included bitmap, in bytes */
639 	__le16 la_reserved1;
640 	__le64 la_reserved2;
641 /*10*/	__u8   la_bitmap[];
642 };
643 
644 /*
645  * Data-in-inode header. This is only used if i_dyn_features has
646  * OCFS2_INLINE_DATA_FL set.
647  */
648 struct ocfs2_inline_data
649 {
650 /*00*/	__le16	id_count;	/* Number of bytes that can be used
651 				 * for data, starting at id_data */
652 	__le16	id_reserved0;
653 	__le32	id_reserved1;
654 	__u8	id_data[];	/* Start of user data */
655 };
656 
657 /*
658  * On disk inode for OCFS2
659  */
660 struct ocfs2_dinode {
661 /*00*/	__u8 i_signature[8];		/* Signature for validation */
662 	__le32 i_generation;		/* Generation number */
663 	__le16 i_suballoc_slot;		/* Slot suballocator this inode
664 					   belongs to */
665 	__le16 i_suballoc_bit;		/* Bit offset in suballocator
666 					   block group */
667 /*10*/	__le16 i_links_count_hi;	/* High 16 bits of links count */
668 	__le16 i_xattr_inline_size;
669 	__le32 i_clusters;		/* Cluster count */
670 	__le32 i_uid;			/* Owner UID */
671 	__le32 i_gid;			/* Owning GID */
672 /*20*/	__le64 i_size;			/* Size in bytes */
673 	__le16 i_mode;			/* File mode */
674 	__le16 i_links_count;		/* Links count */
675 	__le32 i_flags;			/* File flags */
676 /*30*/	__le64 i_atime;			/* Access time */
677 	__le64 i_ctime;			/* Creation time */
678 /*40*/	__le64 i_mtime;			/* Modification time */
679 	__le64 i_dtime;			/* Deletion time */
680 /*50*/	__le64 i_blkno;			/* Offset on disk, in blocks */
681 	__le64 i_last_eb_blk;		/* Pointer to last extent
682 					   block */
683 /*60*/	__le32 i_fs_generation;		/* Generation per fs-instance */
684 	__le32 i_atime_nsec;
685 	__le32 i_ctime_nsec;
686 	__le32 i_mtime_nsec;
687 /*70*/	__le32 i_attr;
688 	__le16 i_orphaned_slot;		/* Only valid when OCFS2_ORPHANED_FL
689 					   was set in i_flags */
690 	__le16 i_dyn_features;
691 	__le64 i_xattr_loc;
692 /*80*/	struct ocfs2_block_check i_check;	/* Error checking */
693 /*88*/	__le64 i_dx_root;		/* Pointer to dir index root block */
694 /*90*/	__le64 i_refcount_loc;
695 	__le64 i_suballoc_loc;		/* Suballocator block group this
696 					   inode belongs to.  Only valid
697 					   if allocated from a
698 					   discontiguous block group */
699 /*A0*/	__le16 i_dio_orphaned_slot;	/* only used for append dio write */
700 	__le16 i_reserved1[3];
701 	__le64 i_reserved2[2];
702 /*B8*/	union {
703 		__le64 i_pad1;		/* Generic way to refer to this
704 					   64bit union */
705 		struct {
706 			__le64 i_rdev;	/* Device number */
707 		} dev1;
708 		struct {		/* Info for bitmap system
709 					   inodes */
710 			__le32 i_used;	/* Bits (ie, clusters) used  */
711 			__le32 i_total;	/* Total bits (clusters)
712 					   available */
713 		} bitmap1;
714 		struct {		/* Info for journal system
715 					   inodes */
716 			__le32 ij_flags;	/* Mounted, version, etc. */
717 			__le32 ij_recovery_generation; /* Incremented when the
718 							  journal is recovered
719 							  after an unclean
720 							  shutdown */
721 		} journal1;
722 	} id1;				/* Inode type dependent 1 */
723 /*C0*/	union {
724 		struct ocfs2_super_block	i_super;
725 		struct ocfs2_local_alloc	i_lab;
726 		struct ocfs2_chain_list		i_chain;
727 		struct ocfs2_extent_list	i_list;
728 		struct ocfs2_truncate_log	i_dealloc;
729 		struct ocfs2_inline_data	i_data;
730 		__u8               		i_symlink[0];
731 	} id2;
732 /* Actual on-disk size is one block */
733 };
734 
735 /*
736  * On-disk directory entry structure for OCFS2
737  *
738  * Packed as this structure could be accessed unaligned on 64-bit platforms
739  */
740 struct ocfs2_dir_entry {
741 /*00*/	__le64   inode;                  /* Inode number */
742 	__le16   rec_len;                /* Directory entry length */
743 	__u8    name_len;               /* Name length */
744 	__u8    file_type;
745 /*0C*/	char    name[OCFS2_MAX_FILENAME_LEN];   /* File name */
746 /* Actual on-disk length specified by rec_len */
747 } __attribute__ ((packed));
748 
749 /*
750  * Per-block record for the unindexed directory btree. This is carefully
751  * crafted so that the rec_len and name_len records of an ocfs2_dir_entry are
752  * mirrored. That way, the directory manipulation code needs a minimal amount
753  * of update.
754  *
755  * NOTE: Keep this structure aligned to a multiple of 4 bytes.
756  */
757 struct ocfs2_dir_block_trailer {
758 /*00*/	__le64		db_compat_inode;	/* Always zero. Was inode */
759 
760 	__le16		db_compat_rec_len;	/* Backwards compatible with
761 						 * ocfs2_dir_entry. */
762 	__u8		db_compat_name_len;	/* Always zero. Was name_len */
763 	__u8		db_reserved0;
764 	__le16		db_reserved1;
765 	__le16		db_free_rec_len;	/* Size of largest empty hole
766 						 * in this block. (unused) */
767 /*10*/	__u8		db_signature[8];	/* Signature for verification */
768 	__le64		db_reserved2;
769 /*20*/	__le64		db_free_next;		/* Next block in list (unused) */
770 	__le64		db_blkno;		/* Offset on disk, in blocks */
771 /*30*/	__le64		db_parent_dinode;	/* dinode which owns me, in
772 						   blocks */
773 	struct ocfs2_block_check db_check;	/* Error checking */
774 /*40*/
775 };
776 
777  /*
778  * A directory entry in the indexed tree. We don't store the full name here,
779  * but instead provide a pointer to the full dirent in the unindexed tree.
780  *
781  * We also store name_len here so as to reduce the number of leaf blocks we
782  * need to search in case of collisions.
783  */
784 struct ocfs2_dx_entry {
785 	__le32		dx_major_hash;	/* Used to find logical
786 					 * cluster in index */
787 	__le32		dx_minor_hash;	/* Lower bits used to find
788 					 * block in cluster */
789 	__le64		dx_dirent_blk;	/* Physical block in unindexed
790 					 * tree holding this dirent. */
791 };
792 
793 struct ocfs2_dx_entry_list {
794 	__le32		de_reserved;
795 	__le16		de_count;	/* Maximum number of entries
796 					 * possible in de_entries */
797 	__le16		de_num_used;	/* Current number of
798 					 * de_entries entries */
799 	struct	ocfs2_dx_entry		de_entries[];	/* Indexed dir entries
800 							 * in a packed array of
801 							 * length de_num_used */
802 };
803 
804 #define OCFS2_DX_FLAG_INLINE	0x01
805 
806 /*
807  * A directory indexing block. Each indexed directory has one of these,
808  * pointed to by ocfs2_dinode.
809  *
810  * This block stores an indexed btree root, and a set of free space
811  * start-of-list pointers.
812  */
813 struct ocfs2_dx_root_block {
814 	__u8		dr_signature[8];	/* Signature for verification */
815 	struct ocfs2_block_check dr_check;	/* Error checking */
816 	__le16		dr_suballoc_slot;	/* Slot suballocator this
817 						 * block belongs to. */
818 	__le16		dr_suballoc_bit;	/* Bit offset in suballocator
819 						 * block group */
820 	__le32		dr_fs_generation;	/* Must match super block */
821 	__le64		dr_blkno;		/* Offset on disk, in blocks */
822 	__le64		dr_last_eb_blk;		/* Pointer to last
823 						 * extent block */
824 	__le32		dr_clusters;		/* Clusters allocated
825 						 * to the indexed tree. */
826 	__u8		dr_flags;		/* OCFS2_DX_FLAG_* flags */
827 	__u8		dr_reserved0;
828 	__le16		dr_reserved1;
829 	__le64		dr_dir_blkno;		/* Pointer to parent inode */
830 	__le32		dr_num_entries;		/* Total number of
831 						 * names stored in
832 						 * this directory.*/
833 	__le32		dr_reserved2;
834 	__le64		dr_free_blk;		/* Pointer to head of free
835 						 * unindexed block list. */
836 	__le64		dr_suballoc_loc;	/* Suballocator block group
837 						   this root belongs to.
838 						   Only valid if allocated
839 						   from a discontiguous
840 						   block group */
841 	__le64		dr_reserved3[14];
842 	union {
843 		struct ocfs2_extent_list dr_list; /* Keep this aligned to 128
844 						   * bits for maximum space
845 						   * efficiency. */
846 		struct ocfs2_dx_entry_list dr_entries; /* In-root-block list of
847 							* entries. We grow out
848 							* to extents if this
849 							* gets too big. */
850 	};
851 };
852 
853 /*
854  * The header of a leaf block in the indexed tree.
855  */
856 struct ocfs2_dx_leaf {
857 	__u8		dl_signature[8];/* Signature for verification */
858 	struct ocfs2_block_check dl_check;	/* Error checking */
859 	__le64		dl_blkno;	/* Offset on disk, in blocks */
860 	__le32		dl_fs_generation;/* Must match super block */
861 	__le32		dl_reserved0;
862 	__le64		dl_reserved1;
863 	struct ocfs2_dx_entry_list	dl_list;
864 };
865 
866 /*
867  * Largest bitmap for a block (suballocator) group in bytes.  This limit
868  * does not affect cluster groups (global allocator).  Cluster group
869  * bitmaps run to the end of the block.
870  */
871 #define OCFS2_MAX_BG_BITMAP_SIZE	256
872 
873 /*
874  * On disk allocator group structure for OCFS2
875  */
876 struct ocfs2_group_desc
877 {
878 /*00*/	__u8    bg_signature[8];        /* Signature for validation */
879 	__le16   bg_size;                /* Size of included bitmap in
880 					   bytes. */
881 	__le16   bg_bits;                /* Bits represented by this
882 					   group. */
883 	__le16	bg_free_bits_count;     /* Free bits count */
884 	__le16   bg_chain;               /* What chain I am in. */
885 /*10*/	__le32   bg_generation;
886 	__le32	bg_reserved1;
887 	__le64   bg_next_group;          /* Next group in my list, in
888 					   blocks */
889 /*20*/	__le64   bg_parent_dinode;       /* dinode which owns me, in
890 					   blocks */
891 	__le64   bg_blkno;               /* Offset on disk, in blocks */
892 /*30*/	struct ocfs2_block_check bg_check;	/* Error checking */
893 	__le64   bg_reserved2;
894 /*40*/	union {
895 		__u8    bg_bitmap[0];
896 		struct {
897 			/*
898 			 * Block groups may be discontiguous when
899 			 * OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG is set.
900 			 * The extents of a discontiguous block group are
901 			 * stored in bg_list.  It is a flat list.
902 			 * l_tree_depth must always be zero.  A
903 			 * discontiguous group is signified by a non-zero
904 			 * bg_list->l_next_free_rec.  Only block groups
905 			 * can be discontiguous; Cluster groups cannot.
906 			 * We've never made a block group with more than
907 			 * 2048 blocks (256 bytes of bg_bitmap).  This
908 			 * codifies that limit so that we can fit bg_list.
909 			 * bg_size of a discontiguous block group will
910 			 * be 256 to match bg_bitmap_filler.
911 			 */
912 			__u8 bg_bitmap_filler[OCFS2_MAX_BG_BITMAP_SIZE];
913 /*140*/			struct ocfs2_extent_list bg_list;
914 		};
915 	};
916 /* Actual on-disk size is one block */
917 };
918 
919 struct ocfs2_refcount_rec {
920 /*00*/	__le64 r_cpos;		/* Physical offset, in clusters */
921 	__le32 r_clusters;	/* Clusters covered by this extent */
922 	__le32 r_refcount;	/* Reference count of this extent */
923 /*10*/
924 };
925 #define OCFS2_32BIT_POS_MASK		(0xffffffffULL)
926 
927 #define OCFS2_REFCOUNT_LEAF_FL          (0x00000001)
928 #define OCFS2_REFCOUNT_TREE_FL          (0x00000002)
929 
930 struct ocfs2_refcount_list {
931 /*00*/	__le16 rl_count;	/* Maximum number of entries possible
932 				   in rl_records */
933 	__le16 rl_used;		/* Current number of used records */
934 	__le32 rl_reserved2;
935 	__le64 rl_reserved1;	/* Pad to sizeof(ocfs2_refcount_record) */
936 /*10*/	struct ocfs2_refcount_rec rl_recs[];	/* Refcount records */
937 };
938 
939 
940 struct ocfs2_refcount_block {
941 /*00*/	__u8 rf_signature[8];		/* Signature for verification */
942 	__le16 rf_suballoc_slot;	/* Slot suballocator this block
943 					   belongs to */
944 	__le16 rf_suballoc_bit;		/* Bit offset in suballocator
945 					   block group */
946 	__le32 rf_fs_generation;	/* Must match superblock */
947 /*10*/	__le64 rf_blkno;		/* Offset on disk, in blocks */
948 	__le64 rf_parent;		/* Parent block, only valid if
949 					   OCFS2_REFCOUNT_LEAF_FL is set in
950 					   rf_flags */
951 /*20*/	struct ocfs2_block_check rf_check;	/* Error checking */
952 	__le64 rf_last_eb_blk;		/* Pointer to last extent block */
953 /*30*/	__le32 rf_count;		/* Number of inodes sharing this
954 					   refcount tree */
955 	__le32 rf_flags;		/* See the flags above */
956 	__le32 rf_clusters;		/* clusters covered by refcount tree. */
957 	__le32 rf_cpos;			/* cluster offset in refcount tree.*/
958 /*40*/	__le32 rf_generation;		/* generation number. all be the same
959 					 * for the same refcount tree. */
960 	__le32 rf_reserved0;
961 	__le64 rf_suballoc_loc;		/* Suballocator block group this
962 					   refcount block belongs to. Only
963 					   valid if allocated from a
964 					   discontiguous block group */
965 /*50*/	__le64 rf_reserved1[6];
966 /*80*/	union {
967 		struct ocfs2_refcount_list rf_records;  /* List of refcount
968 							  records */
969 		struct ocfs2_extent_list rf_list;	/* Extent record list,
970 							only valid if
971 							OCFS2_REFCOUNT_TREE_FL
972 							is set in rf_flags */
973 	};
974 /* Actual on-disk size is one block */
975 };
976 
977 /*
978  * On disk extended attribute structure for OCFS2.
979  */
980 
981 /*
982  * ocfs2_xattr_entry indicates one extend attribute.
983  *
984  * Note that it can be stored in inode, one block or one xattr bucket.
985  */
986 struct ocfs2_xattr_entry {
987 	__le32	xe_name_hash;    /* hash value of xattr prefix+suffix. */
988 	__le16	xe_name_offset;  /* byte offset from the 1st entry in the
989 				    local xattr storage(inode, xattr block or
990 				    xattr bucket). */
991 	__u8	xe_name_len;	 /* xattr name len, doesn't include prefix. */
992 	__u8	xe_type;         /* the low 7 bits indicate the name prefix
993 				  * type and the highest bit indicates whether
994 				  * the EA is stored in the local storage. */
995 	__le64	xe_value_size;	 /* real xattr value length. */
996 };
997 
998 /*
999  * On disk structure for xattr header.
1000  *
1001  * One ocfs2_xattr_header describes how many ocfs2_xattr_entry records in
1002  * the local xattr storage.
1003  */
1004 struct ocfs2_xattr_header {
1005 	__le16	xh_count;                       /* contains the count of how
1006 						   many records are in the
1007 						   local xattr storage. */
1008 	__le16	xh_free_start;                  /* current offset for storing
1009 						   xattr. */
1010 	__le16	xh_name_value_len;              /* total length of name/value
1011 						   length in this bucket. */
1012 	__le16	xh_num_buckets;                 /* Number of xattr buckets
1013 						   in this extent record,
1014 						   only valid in the first
1015 						   bucket. */
1016 	struct ocfs2_block_check xh_check;	/* Error checking
1017 						   (Note, this is only
1018 						    used for xattr
1019 						    buckets.  A block uses
1020 						    xb_check and sets
1021 						    this field to zero.) */
1022 	struct ocfs2_xattr_entry xh_entries[]; /* xattr entry list. */
1023 };
1024 
1025 /*
1026  * On disk structure for xattr value root.
1027  *
1028  * When an xattr's value is large enough, it is stored in an external
1029  * b-tree like file data.  The xattr value root points to this structure.
1030  */
1031 struct ocfs2_xattr_value_root {
1032 /*00*/	__le32	xr_clusters;              /* clusters covered by xattr value. */
1033 	__le32	xr_reserved0;
1034 	__le64	xr_last_eb_blk;           /* Pointer to last extent block */
1035 /*10*/	struct ocfs2_extent_list xr_list; /* Extent record list */
1036 };
1037 
1038 /*
1039  * On disk structure for xattr tree root.
1040  *
1041  * It is used when there are too many extended attributes for one file. These
1042  * attributes will be organized and stored in an indexed-btree.
1043  */
1044 struct ocfs2_xattr_tree_root {
1045 /*00*/	__le32	xt_clusters;              /* clusters covered by xattr. */
1046 	__le32	xt_reserved0;
1047 	__le64	xt_last_eb_blk;           /* Pointer to last extent block */
1048 /*10*/	struct ocfs2_extent_list xt_list; /* Extent record list */
1049 };
1050 
1051 #define OCFS2_XATTR_INDEXED	0x1
1052 #define OCFS2_HASH_SHIFT	5
1053 #define OCFS2_XATTR_ROUND	3
1054 #define OCFS2_XATTR_SIZE(size)	(((size) + OCFS2_XATTR_ROUND) & \
1055 				~(OCFS2_XATTR_ROUND))
1056 
1057 #define OCFS2_XATTR_BUCKET_SIZE			4096
1058 #define OCFS2_XATTR_MAX_BLOCKS_PER_BUCKET 	(OCFS2_XATTR_BUCKET_SIZE \
1059 						 / OCFS2_MIN_BLOCKSIZE)
1060 
1061 /*
1062  * On disk structure for xattr block.
1063  */
1064 struct ocfs2_xattr_block {
1065 /*00*/	__u8	xb_signature[8];     /* Signature for verification */
1066 	__le16	xb_suballoc_slot;    /* Slot suballocator this
1067 					block belongs to. */
1068 	__le16	xb_suballoc_bit;     /* Bit offset in suballocator
1069 					block group */
1070 	__le32	xb_fs_generation;    /* Must match super block */
1071 /*10*/	__le64	xb_blkno;            /* Offset on disk, in blocks */
1072 	struct ocfs2_block_check xb_check;	/* Error checking */
1073 /*20*/	__le16	xb_flags;            /* Indicates whether this block contains
1074 					real xattr or a xattr tree. */
1075 	__le16	xb_reserved0;
1076 	__le32  xb_reserved1;
1077 	__le64	xb_suballoc_loc;	/* Suballocator block group this
1078 					   xattr block belongs to. Only
1079 					   valid if allocated from a
1080 					   discontiguous block group */
1081 /*30*/	union {
1082 		struct ocfs2_xattr_header xb_header; /* xattr header if this
1083 							block contains xattr */
1084 		struct ocfs2_xattr_tree_root xb_root;/* xattr tree root if this
1085 							block cotains xattr
1086 							tree. */
1087 	} xb_attrs;
1088 };
1089 
1090 #define OCFS2_XATTR_ENTRY_LOCAL		0x80
1091 #define OCFS2_XATTR_TYPE_MASK		0x7F
1092 static inline void ocfs2_xattr_set_local(struct ocfs2_xattr_entry *xe,
1093 					 int local)
1094 {
1095 	if (local)
1096 		xe->xe_type |= OCFS2_XATTR_ENTRY_LOCAL;
1097 	else
1098 		xe->xe_type &= ~OCFS2_XATTR_ENTRY_LOCAL;
1099 }
1100 
1101 static inline int ocfs2_xattr_is_local(struct ocfs2_xattr_entry *xe)
1102 {
1103 	return xe->xe_type & OCFS2_XATTR_ENTRY_LOCAL;
1104 }
1105 
1106 static inline void ocfs2_xattr_set_type(struct ocfs2_xattr_entry *xe, int type)
1107 {
1108 	xe->xe_type |= type & OCFS2_XATTR_TYPE_MASK;
1109 }
1110 
1111 static inline int ocfs2_xattr_get_type(struct ocfs2_xattr_entry *xe)
1112 {
1113 	return xe->xe_type & OCFS2_XATTR_TYPE_MASK;
1114 }
1115 
1116 /*
1117  *  On disk structures for global quota file
1118  */
1119 
1120 /* Magic numbers and known versions for global quota files */
1121 #define OCFS2_GLOBAL_QMAGICS {\
1122 	0x0cf52470, /* USRQUOTA */ \
1123 	0x0cf52471  /* GRPQUOTA */ \
1124 }
1125 
1126 #define OCFS2_GLOBAL_QVERSIONS {\
1127 	0, \
1128 	0, \
1129 }
1130 
1131 
1132 /* Each block of each quota file has a certain fixed number of bytes reserved
1133  * for OCFS2 internal use at its end. OCFS2 can use it for things like
1134  * checksums, etc. */
1135 #define OCFS2_QBLK_RESERVED_SPACE 8
1136 
1137 /* Generic header of all quota files */
1138 struct ocfs2_disk_dqheader {
1139 	__le32 dqh_magic;	/* Magic number identifying file */
1140 	__le32 dqh_version;	/* Quota format version */
1141 };
1142 
1143 #define OCFS2_GLOBAL_INFO_OFF (sizeof(struct ocfs2_disk_dqheader))
1144 
1145 /* Information header of global quota file (immediately follows the generic
1146  * header) */
1147 struct ocfs2_global_disk_dqinfo {
1148 /*00*/	__le32 dqi_bgrace;	/* Grace time for space softlimit excess */
1149 	__le32 dqi_igrace;	/* Grace time for inode softlimit excess */
1150 	__le32 dqi_syncms;	/* Time after which we sync local changes to
1151 				 * global quota file */
1152 	__le32 dqi_blocks;	/* Number of blocks in quota file */
1153 /*10*/	__le32 dqi_free_blk;	/* First free block in quota file */
1154 	__le32 dqi_free_entry;	/* First block with free dquot entry in quota
1155 				 * file */
1156 };
1157 
1158 /* Structure with global user / group information. We reserve some space
1159  * for future use. */
1160 struct ocfs2_global_disk_dqblk {
1161 /*00*/	__le32 dqb_id;          /* ID the structure belongs to */
1162 	__le32 dqb_use_count;   /* Number of nodes having reference to this structure */
1163 	__le64 dqb_ihardlimit;  /* absolute limit on allocated inodes */
1164 /*10*/	__le64 dqb_isoftlimit;  /* preferred inode limit */
1165 	__le64 dqb_curinodes;   /* current # allocated inodes */
1166 /*20*/	__le64 dqb_bhardlimit;  /* absolute limit on disk space */
1167 	__le64 dqb_bsoftlimit;  /* preferred limit on disk space */
1168 /*30*/	__le64 dqb_curspace;    /* current space occupied */
1169 	__le64 dqb_btime;       /* time limit for excessive disk use */
1170 /*40*/	__le64 dqb_itime;       /* time limit for excessive inode use */
1171 	__le64 dqb_pad1;
1172 /*50*/	__le64 dqb_pad2;
1173 };
1174 
1175 /*
1176  *  On-disk structures for local quota file
1177  */
1178 
1179 /* Magic numbers and known versions for local quota files */
1180 #define OCFS2_LOCAL_QMAGICS {\
1181 	0x0cf524c0, /* USRQUOTA */ \
1182 	0x0cf524c1  /* GRPQUOTA */ \
1183 }
1184 
1185 #define OCFS2_LOCAL_QVERSIONS {\
1186 	0, \
1187 	0, \
1188 }
1189 
1190 /* Quota flags in dqinfo header */
1191 #define OLQF_CLEAN	0x0001	/* Quota file is empty (this should be after\
1192 				 * quota has been cleanly turned off) */
1193 
1194 #define OCFS2_LOCAL_INFO_OFF (sizeof(struct ocfs2_disk_dqheader))
1195 
1196 /* Information header of local quota file (immediately follows the generic
1197  * header) */
1198 struct ocfs2_local_disk_dqinfo {
1199 	__le32 dqi_flags;	/* Flags for quota file */
1200 	__le32 dqi_chunks;	/* Number of chunks of quota structures
1201 				 * with a bitmap */
1202 	__le32 dqi_blocks;	/* Number of blocks allocated for quota file */
1203 };
1204 
1205 /* Header of one chunk of a quota file */
1206 struct ocfs2_local_disk_chunk {
1207 	__le32 dqc_free;	/* Number of free entries in the bitmap */
1208 	__u8 dqc_bitmap[];	/* Bitmap of entries in the corresponding
1209 				 * chunk of quota file */
1210 };
1211 
1212 /* One entry in local quota file */
1213 struct ocfs2_local_disk_dqblk {
1214 /*00*/	__le64 dqb_id;		/* id this quota applies to */
1215 	__le64 dqb_spacemod;	/* Change in the amount of used space */
1216 /*10*/	__le64 dqb_inodemod;	/* Change in the amount of used inodes */
1217 };
1218 
1219 
1220 /*
1221  * The quota trailer lives at the end of each quota block.
1222  */
1223 
1224 struct ocfs2_disk_dqtrailer {
1225 /*00*/	struct ocfs2_block_check dq_check;	/* Error checking */
1226 /*08*/	/* Cannot be larger than OCFS2_QBLK_RESERVED_SPACE */
1227 };
1228 
1229 static inline struct ocfs2_disk_dqtrailer *ocfs2_block_dqtrailer(int blocksize,
1230 								 void *buf)
1231 {
1232 	char *ptr = buf;
1233 	ptr += blocksize - OCFS2_QBLK_RESERVED_SPACE;
1234 
1235 	return (struct ocfs2_disk_dqtrailer *)ptr;
1236 }
1237 
1238 #ifdef __KERNEL__
1239 static inline int ocfs2_fast_symlink_chars(struct super_block *sb)
1240 {
1241 	return  sb->s_blocksize -
1242 		 offsetof(struct ocfs2_dinode, id2.i_symlink);
1243 }
1244 
1245 static inline int ocfs2_max_inline_data_with_xattr(struct super_block *sb,
1246 						   struct ocfs2_dinode *di)
1247 {
1248 	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
1249 
1250 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
1251 		return sb->s_blocksize -
1252 			offsetof(struct ocfs2_dinode, id2.i_data.id_data) -
1253 			xattrsize;
1254 	else
1255 		return sb->s_blocksize -
1256 			offsetof(struct ocfs2_dinode, id2.i_data.id_data);
1257 }
1258 
1259 static inline int ocfs2_extent_recs_per_inode(struct super_block *sb)
1260 {
1261 	int size;
1262 
1263 	size = sb->s_blocksize -
1264 		offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1265 
1266 	return size / sizeof(struct ocfs2_extent_rec);
1267 }
1268 
1269 static inline int ocfs2_extent_recs_per_inode_with_xattr(
1270 						struct super_block *sb,
1271 						struct ocfs2_dinode *di)
1272 {
1273 	int size;
1274 	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
1275 
1276 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
1277 		size = sb->s_blocksize -
1278 			offsetof(struct ocfs2_dinode, id2.i_list.l_recs) -
1279 			xattrsize;
1280 	else
1281 		size = sb->s_blocksize -
1282 			offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1283 
1284 	return size / sizeof(struct ocfs2_extent_rec);
1285 }
1286 
1287 static inline int ocfs2_extent_recs_per_dx_root(struct super_block *sb)
1288 {
1289 	int size;
1290 
1291 	size = sb->s_blocksize -
1292 		offsetof(struct ocfs2_dx_root_block, dr_list.l_recs);
1293 
1294 	return size / sizeof(struct ocfs2_extent_rec);
1295 }
1296 
1297 static inline int ocfs2_chain_recs_per_inode(struct super_block *sb)
1298 {
1299 	int size;
1300 
1301 	size = sb->s_blocksize -
1302 		offsetof(struct ocfs2_dinode, id2.i_chain.cl_recs);
1303 
1304 	return size / sizeof(struct ocfs2_chain_rec);
1305 }
1306 
1307 static inline u16 ocfs2_extent_recs_per_eb(struct super_block *sb)
1308 {
1309 	int size;
1310 
1311 	size = sb->s_blocksize -
1312 		offsetof(struct ocfs2_extent_block, h_list.l_recs);
1313 
1314 	return size / sizeof(struct ocfs2_extent_rec);
1315 }
1316 
1317 static inline u16 ocfs2_extent_recs_per_gd(struct super_block *sb)
1318 {
1319 	int size;
1320 
1321 	size = sb->s_blocksize -
1322 		offsetof(struct ocfs2_group_desc, bg_list.l_recs);
1323 
1324 	return size / sizeof(struct ocfs2_extent_rec);
1325 }
1326 
1327 static inline int ocfs2_dx_entries_per_leaf(struct super_block *sb)
1328 {
1329 	int size;
1330 
1331 	size = sb->s_blocksize -
1332 		offsetof(struct ocfs2_dx_leaf, dl_list.de_entries);
1333 
1334 	return size / sizeof(struct ocfs2_dx_entry);
1335 }
1336 
1337 static inline int ocfs2_dx_entries_per_root(struct super_block *sb)
1338 {
1339 	int size;
1340 
1341 	size = sb->s_blocksize -
1342 		offsetof(struct ocfs2_dx_root_block, dr_entries.de_entries);
1343 
1344 	return size / sizeof(struct ocfs2_dx_entry);
1345 }
1346 
1347 static inline u16 ocfs2_local_alloc_size(struct super_block *sb)
1348 {
1349 	u16 size;
1350 
1351 	size = sb->s_blocksize -
1352 		offsetof(struct ocfs2_dinode, id2.i_lab.la_bitmap);
1353 
1354 	return size;
1355 }
1356 
1357 static inline int ocfs2_group_bitmap_size(struct super_block *sb,
1358 					  int suballocator,
1359 					  u32 feature_incompat)
1360 {
1361 	int size = sb->s_blocksize -
1362 		offsetof(struct ocfs2_group_desc, bg_bitmap);
1363 
1364 	/*
1365 	 * The cluster allocator uses the entire block.  Suballocators have
1366 	 * never used more than OCFS2_MAX_BG_BITMAP_SIZE.  Unfortunately, older
1367 	 * code expects bg_size set to the maximum.  Thus we must keep
1368 	 * bg_size as-is unless discontig_bg is enabled.
1369 	 */
1370 	if (suballocator &&
1371 	    (feature_incompat & OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG))
1372 		size = OCFS2_MAX_BG_BITMAP_SIZE;
1373 
1374 	return size;
1375 }
1376 
1377 static inline int ocfs2_truncate_recs_per_inode(struct super_block *sb)
1378 {
1379 	int size;
1380 
1381 	size = sb->s_blocksize -
1382 		offsetof(struct ocfs2_dinode, id2.i_dealloc.tl_recs);
1383 
1384 	return size / sizeof(struct ocfs2_truncate_rec);
1385 }
1386 
1387 static inline u64 ocfs2_backup_super_blkno(struct super_block *sb, int index)
1388 {
1389 	u64 offset = OCFS2_BACKUP_SB_START;
1390 
1391 	if (index >= 0 && index < OCFS2_MAX_BACKUP_SUPERBLOCKS) {
1392 		offset <<= (2 * index);
1393 		offset >>= sb->s_blocksize_bits;
1394 		return offset;
1395 	}
1396 
1397 	return 0;
1398 
1399 }
1400 
1401 static inline u16 ocfs2_xattr_recs_per_xb(struct super_block *sb)
1402 {
1403 	int size;
1404 
1405 	size = sb->s_blocksize -
1406 		offsetof(struct ocfs2_xattr_block,
1407 			 xb_attrs.xb_root.xt_list.l_recs);
1408 
1409 	return size / sizeof(struct ocfs2_extent_rec);
1410 }
1411 
1412 static inline u16 ocfs2_extent_recs_per_rb(struct super_block *sb)
1413 {
1414 	int size;
1415 
1416 	size = sb->s_blocksize -
1417 		offsetof(struct ocfs2_refcount_block, rf_list.l_recs);
1418 
1419 	return size / sizeof(struct ocfs2_extent_rec);
1420 }
1421 
1422 static inline u16 ocfs2_refcount_recs_per_rb(struct super_block *sb)
1423 {
1424 	int size;
1425 
1426 	size = sb->s_blocksize -
1427 		offsetof(struct ocfs2_refcount_block, rf_records.rl_recs);
1428 
1429 	return size / sizeof(struct ocfs2_refcount_rec);
1430 }
1431 
1432 static inline u32
1433 ocfs2_get_ref_rec_low_cpos(const struct ocfs2_refcount_rec *rec)
1434 {
1435 	return le64_to_cpu(rec->r_cpos) & OCFS2_32BIT_POS_MASK;
1436 }
1437 #else
1438 static inline int ocfs2_fast_symlink_chars(int blocksize)
1439 {
1440 	return blocksize - offsetof(struct ocfs2_dinode, id2.i_symlink);
1441 }
1442 
1443 static inline int ocfs2_max_inline_data_with_xattr(int blocksize,
1444 						   struct ocfs2_dinode *di)
1445 {
1446 	if (di && (di->i_dyn_features & OCFS2_INLINE_XATTR_FL))
1447 		return blocksize -
1448 			offsetof(struct ocfs2_dinode, id2.i_data.id_data) -
1449 			di->i_xattr_inline_size;
1450 	else
1451 		return blocksize -
1452 			offsetof(struct ocfs2_dinode, id2.i_data.id_data);
1453 }
1454 
1455 static inline int ocfs2_extent_recs_per_inode(int blocksize)
1456 {
1457 	int size;
1458 
1459 	size = blocksize -
1460 		offsetof(struct ocfs2_dinode, id2.i_list.l_recs);
1461 
1462 	return size / sizeof(struct ocfs2_extent_rec);
1463 }
1464 
1465 static inline int ocfs2_chain_recs_per_inode(int blocksize)
1466 {
1467 	int size;
1468 
1469 	size = blocksize -
1470 		offsetof(struct ocfs2_dinode, id2.i_chain.cl_recs);
1471 
1472 	return size / sizeof(struct ocfs2_chain_rec);
1473 }
1474 
1475 static inline int ocfs2_extent_recs_per_eb(int blocksize)
1476 {
1477 	int size;
1478 
1479 	size = blocksize -
1480 		offsetof(struct ocfs2_extent_block, h_list.l_recs);
1481 
1482 	return size / sizeof(struct ocfs2_extent_rec);
1483 }
1484 
1485 static inline int ocfs2_extent_recs_per_gd(int blocksize)
1486 {
1487 	int size;
1488 
1489 	size = blocksize -
1490 		offsetof(struct ocfs2_group_desc, bg_list.l_recs);
1491 
1492 	return size / sizeof(struct ocfs2_extent_rec);
1493 }
1494 
1495 static inline int ocfs2_local_alloc_size(int blocksize)
1496 {
1497 	int size;
1498 
1499 	size = blocksize -
1500 		offsetof(struct ocfs2_dinode, id2.i_lab.la_bitmap);
1501 
1502 	return size;
1503 }
1504 
1505 static inline int ocfs2_group_bitmap_size(int blocksize,
1506 					  int suballocator,
1507 					  uint32_t feature_incompat)
1508 {
1509 	int size = sb->s_blocksize -
1510 		offsetof(struct ocfs2_group_desc, bg_bitmap);
1511 
1512 	/*
1513 	 * The cluster allocator uses the entire block.  Suballocators have
1514 	 * never used more than OCFS2_MAX_BG_BITMAP_SIZE.  Unfortunately, older
1515 	 * code expects bg_size set to the maximum.  Thus we must keep
1516 	 * bg_size as-is unless discontig_bg is enabled.
1517 	 */
1518 	if (suballocator &&
1519 	    (feature_incompat & OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG))
1520 		size = OCFS2_MAX_BG_BITMAP_SIZE;
1521 
1522 	return size;
1523 }
1524 
1525 static inline int ocfs2_truncate_recs_per_inode(int blocksize)
1526 {
1527 	int size;
1528 
1529 	size = blocksize -
1530 		offsetof(struct ocfs2_dinode, id2.i_dealloc.tl_recs);
1531 
1532 	return size / sizeof(struct ocfs2_truncate_rec);
1533 }
1534 
1535 static inline uint64_t ocfs2_backup_super_blkno(int blocksize, int index)
1536 {
1537 	uint64_t offset = OCFS2_BACKUP_SB_START;
1538 
1539 	if (index >= 0 && index < OCFS2_MAX_BACKUP_SUPERBLOCKS) {
1540 		offset <<= (2 * index);
1541 		offset /= blocksize;
1542 		return offset;
1543 	}
1544 
1545 	return 0;
1546 }
1547 
1548 static inline int ocfs2_xattr_recs_per_xb(int blocksize)
1549 {
1550 	int size;
1551 
1552 	size = blocksize -
1553 		offsetof(struct ocfs2_xattr_block,
1554 			 xb_attrs.xb_root.xt_list.l_recs);
1555 
1556 	return size / sizeof(struct ocfs2_extent_rec);
1557 }
1558 #endif  /* __KERNEL__ */
1559 
1560 
1561 static inline int ocfs2_system_inode_is_global(int type)
1562 {
1563 	return ((type >= 0) &&
1564 		(type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE));
1565 }
1566 
1567 static inline int ocfs2_sprintf_system_inode_name(char *buf, int len,
1568 						  int type, int slot)
1569 {
1570 	int chars;
1571 
1572         /*
1573          * Global system inodes can only have one copy.  Everything
1574          * after OCFS2_LAST_GLOBAL_SYSTEM_INODE in the system inode
1575          * list has a copy per slot.
1576          */
1577 	if (type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE)
1578 		chars = snprintf(buf, len, "%s",
1579 				 ocfs2_system_inodes[type].si_name);
1580 	else
1581 		chars = snprintf(buf, len,
1582 				 ocfs2_system_inodes[type].si_name,
1583 				 slot);
1584 
1585 	return chars;
1586 }
1587 
1588 static inline void ocfs2_set_de_type(struct ocfs2_dir_entry *de,
1589 				    umode_t mode)
1590 {
1591 	de->file_type = fs_umode_to_ftype(mode);
1592 }
1593 
1594 static inline int ocfs2_gd_is_discontig(struct ocfs2_group_desc *gd)
1595 {
1596 	if ((offsetof(struct ocfs2_group_desc, bg_bitmap) +
1597 	     le16_to_cpu(gd->bg_size)) !=
1598 	    offsetof(struct ocfs2_group_desc, bg_list))
1599 		return 0;
1600 	/*
1601 	 * Only valid to check l_next_free_rec if
1602 	 * bg_bitmap + bg_size == bg_list.
1603 	 */
1604 	if (!gd->bg_list.l_next_free_rec)
1605 		return 0;
1606 	return 1;
1607 }
1608 #endif  /* _OCFS2_FS_H */
1609 
1610