xref: /openbmc/linux/fs/xfs/libxfs/xfs_format.h (revision 6f4eaea2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
4  * All Rights Reserved.
5  */
6 #ifndef __XFS_FORMAT_H__
7 #define __XFS_FORMAT_H__
8 
9 /*
10  * XFS On Disk Format Definitions
11  *
12  * This header file defines all the on-disk format definitions for
13  * general XFS objects. Directory and attribute related objects are defined in
14  * xfs_da_format.h, which log and log item formats are defined in
15  * xfs_log_format.h. Everything else goes here.
16  */
17 
18 struct xfs_mount;
19 struct xfs_trans;
20 struct xfs_inode;
21 struct xfs_buf;
22 struct xfs_ifork;
23 
24 /*
25  * Super block
26  * Fits into a sector-sized buffer at address 0 of each allocation group.
27  * Only the first of these is ever updated except during growfs.
28  */
29 #define	XFS_SB_MAGIC		0x58465342	/* 'XFSB' */
30 #define	XFS_SB_VERSION_1	1		/* 5.3, 6.0.1, 6.1 */
31 #define	XFS_SB_VERSION_2	2		/* 6.2 - attributes */
32 #define	XFS_SB_VERSION_3	3		/* 6.2 - new inode version */
33 #define	XFS_SB_VERSION_4	4		/* 6.2+ - bitmask version */
34 #define	XFS_SB_VERSION_5	5		/* CRC enabled filesystem */
35 #define	XFS_SB_VERSION_NUMBITS		0x000f
36 #define	XFS_SB_VERSION_ALLFBITS		0xfff0
37 #define	XFS_SB_VERSION_ATTRBIT		0x0010
38 #define	XFS_SB_VERSION_NLINKBIT		0x0020
39 #define	XFS_SB_VERSION_QUOTABIT		0x0040
40 #define	XFS_SB_VERSION_ALIGNBIT		0x0080
41 #define	XFS_SB_VERSION_DALIGNBIT	0x0100
42 #define	XFS_SB_VERSION_SHAREDBIT	0x0200
43 #define XFS_SB_VERSION_LOGV2BIT		0x0400
44 #define XFS_SB_VERSION_SECTORBIT	0x0800
45 #define	XFS_SB_VERSION_EXTFLGBIT	0x1000
46 #define	XFS_SB_VERSION_DIRV2BIT		0x2000
47 #define	XFS_SB_VERSION_BORGBIT		0x4000	/* ASCII only case-insens. */
48 #define	XFS_SB_VERSION_MOREBITSBIT	0x8000
49 
50 /*
51  * The size of a single extended attribute on disk is limited by
52  * the size of index values within the attribute entries themselves.
53  * These are be16 fields, so we can only support attribute data
54  * sizes up to 2^16 bytes in length.
55  */
56 #define XFS_XATTR_SIZE_MAX (1 << 16)
57 
58 /*
59  * Supported feature bit list is just all bits in the versionnum field because
60  * we've used them all up and understand them all. Except, of course, for the
61  * shared superblock bit, which nobody knows what it does and so is unsupported.
62  */
63 #define	XFS_SB_VERSION_OKBITS		\
64 	((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
65 		~XFS_SB_VERSION_SHAREDBIT)
66 
67 /*
68  * There are two words to hold XFS "feature" bits: the original
69  * word, sb_versionnum, and sb_features2.  Whenever a bit is set in
70  * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
71  *
72  * These defines represent bits in sb_features2.
73  */
74 #define XFS_SB_VERSION2_RESERVED1BIT	0x00000001
75 #define XFS_SB_VERSION2_LAZYSBCOUNTBIT	0x00000002	/* Superblk counters */
76 #define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
77 #define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */
78 #define XFS_SB_VERSION2_PARENTBIT	0x00000010	/* parent pointers */
79 #define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */
80 #define XFS_SB_VERSION2_CRCBIT		0x00000100	/* metadata CRCs */
81 #define XFS_SB_VERSION2_FTYPE		0x00000200	/* inode type in dir */
82 
83 #define	XFS_SB_VERSION2_OKBITS		\
84 	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
85 	 XFS_SB_VERSION2_ATTR2BIT	| \
86 	 XFS_SB_VERSION2_PROJID32BIT	| \
87 	 XFS_SB_VERSION2_FTYPE)
88 
89 /* Maximum size of the xfs filesystem label, no terminating NULL */
90 #define XFSLABEL_MAX			12
91 
92 /*
93  * Superblock - in core version.  Must match the ondisk version below.
94  * Must be padded to 64 bit alignment.
95  */
96 typedef struct xfs_sb {
97 	uint32_t	sb_magicnum;	/* magic number == XFS_SB_MAGIC */
98 	uint32_t	sb_blocksize;	/* logical block size, bytes */
99 	xfs_rfsblock_t	sb_dblocks;	/* number of data blocks */
100 	xfs_rfsblock_t	sb_rblocks;	/* number of realtime blocks */
101 	xfs_rtblock_t	sb_rextents;	/* number of realtime extents */
102 	uuid_t		sb_uuid;	/* user-visible file system unique id */
103 	xfs_fsblock_t	sb_logstart;	/* starting block of log if internal */
104 	xfs_ino_t	sb_rootino;	/* root inode number */
105 	xfs_ino_t	sb_rbmino;	/* bitmap inode for realtime extents */
106 	xfs_ino_t	sb_rsumino;	/* summary inode for rt bitmap */
107 	xfs_agblock_t	sb_rextsize;	/* realtime extent size, blocks */
108 	xfs_agblock_t	sb_agblocks;	/* size of an allocation group */
109 	xfs_agnumber_t	sb_agcount;	/* number of allocation groups */
110 	xfs_extlen_t	sb_rbmblocks;	/* number of rt bitmap blocks */
111 	xfs_extlen_t	sb_logblocks;	/* number of log blocks */
112 	uint16_t	sb_versionnum;	/* header version == XFS_SB_VERSION */
113 	uint16_t	sb_sectsize;	/* volume sector size, bytes */
114 	uint16_t	sb_inodesize;	/* inode size, bytes */
115 	uint16_t	sb_inopblock;	/* inodes per block */
116 	char		sb_fname[XFSLABEL_MAX]; /* file system name */
117 	uint8_t		sb_blocklog;	/* log2 of sb_blocksize */
118 	uint8_t		sb_sectlog;	/* log2 of sb_sectsize */
119 	uint8_t		sb_inodelog;	/* log2 of sb_inodesize */
120 	uint8_t		sb_inopblog;	/* log2 of sb_inopblock */
121 	uint8_t		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
122 	uint8_t		sb_rextslog;	/* log2 of sb_rextents */
123 	uint8_t		sb_inprogress;	/* mkfs is in progress, don't mount */
124 	uint8_t		sb_imax_pct;	/* max % of fs for inode space */
125 					/* statistics */
126 	/*
127 	 * These fields must remain contiguous.  If you really
128 	 * want to change their layout, make sure you fix the
129 	 * code in xfs_trans_apply_sb_deltas().
130 	 */
131 	uint64_t	sb_icount;	/* allocated inodes */
132 	uint64_t	sb_ifree;	/* free inodes */
133 	uint64_t	sb_fdblocks;	/* free data blocks */
134 	uint64_t	sb_frextents;	/* free realtime extents */
135 	/*
136 	 * End contiguous fields.
137 	 */
138 	xfs_ino_t	sb_uquotino;	/* user quota inode */
139 	xfs_ino_t	sb_gquotino;	/* group quota inode */
140 	uint16_t	sb_qflags;	/* quota flags */
141 	uint8_t		sb_flags;	/* misc. flags */
142 	uint8_t		sb_shared_vn;	/* shared version number */
143 	xfs_extlen_t	sb_inoalignmt;	/* inode chunk alignment, fsblocks */
144 	uint32_t	sb_unit;	/* stripe or raid unit */
145 	uint32_t	sb_width;	/* stripe or raid width */
146 	uint8_t		sb_dirblklog;	/* log2 of dir block size (fsbs) */
147 	uint8_t		sb_logsectlog;	/* log2 of the log sector size */
148 	uint16_t	sb_logsectsize;	/* sector size for the log, bytes */
149 	uint32_t	sb_logsunit;	/* stripe unit size for the log */
150 	uint32_t	sb_features2;	/* additional feature bits */
151 
152 	/*
153 	 * bad features2 field as a result of failing to pad the sb structure to
154 	 * 64 bits. Some machines will be using this field for features2 bits.
155 	 * Easiest just to mark it bad and not use it for anything else.
156 	 *
157 	 * This is not kept up to date in memory; it is always overwritten by
158 	 * the value in sb_features2 when formatting the incore superblock to
159 	 * the disk buffer.
160 	 */
161 	uint32_t	sb_bad_features2;
162 
163 	/* version 5 superblock fields start here */
164 
165 	/* feature masks */
166 	uint32_t	sb_features_compat;
167 	uint32_t	sb_features_ro_compat;
168 	uint32_t	sb_features_incompat;
169 	uint32_t	sb_features_log_incompat;
170 
171 	uint32_t	sb_crc;		/* superblock crc */
172 	xfs_extlen_t	sb_spino_align;	/* sparse inode chunk alignment */
173 
174 	xfs_ino_t	sb_pquotino;	/* project quota inode */
175 	xfs_lsn_t	sb_lsn;		/* last write sequence */
176 	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
177 
178 	/* must be padded to 64 bit alignment */
179 } xfs_sb_t;
180 
181 #define XFS_SB_CRC_OFF		offsetof(struct xfs_sb, sb_crc)
182 
183 /*
184  * Superblock - on disk version.  Must match the in core version above.
185  * Must be padded to 64 bit alignment.
186  */
187 typedef struct xfs_dsb {
188 	__be32		sb_magicnum;	/* magic number == XFS_SB_MAGIC */
189 	__be32		sb_blocksize;	/* logical block size, bytes */
190 	__be64		sb_dblocks;	/* number of data blocks */
191 	__be64		sb_rblocks;	/* number of realtime blocks */
192 	__be64		sb_rextents;	/* number of realtime extents */
193 	uuid_t		sb_uuid;	/* user-visible file system unique id */
194 	__be64		sb_logstart;	/* starting block of log if internal */
195 	__be64		sb_rootino;	/* root inode number */
196 	__be64		sb_rbmino;	/* bitmap inode for realtime extents */
197 	__be64		sb_rsumino;	/* summary inode for rt bitmap */
198 	__be32		sb_rextsize;	/* realtime extent size, blocks */
199 	__be32		sb_agblocks;	/* size of an allocation group */
200 	__be32		sb_agcount;	/* number of allocation groups */
201 	__be32		sb_rbmblocks;	/* number of rt bitmap blocks */
202 	__be32		sb_logblocks;	/* number of log blocks */
203 	__be16		sb_versionnum;	/* header version == XFS_SB_VERSION */
204 	__be16		sb_sectsize;	/* volume sector size, bytes */
205 	__be16		sb_inodesize;	/* inode size, bytes */
206 	__be16		sb_inopblock;	/* inodes per block */
207 	char		sb_fname[XFSLABEL_MAX]; /* file system name */
208 	__u8		sb_blocklog;	/* log2 of sb_blocksize */
209 	__u8		sb_sectlog;	/* log2 of sb_sectsize */
210 	__u8		sb_inodelog;	/* log2 of sb_inodesize */
211 	__u8		sb_inopblog;	/* log2 of sb_inopblock */
212 	__u8		sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
213 	__u8		sb_rextslog;	/* log2 of sb_rextents */
214 	__u8		sb_inprogress;	/* mkfs is in progress, don't mount */
215 	__u8		sb_imax_pct;	/* max % of fs for inode space */
216 					/* statistics */
217 	/*
218 	 * These fields must remain contiguous.  If you really
219 	 * want to change their layout, make sure you fix the
220 	 * code in xfs_trans_apply_sb_deltas().
221 	 */
222 	__be64		sb_icount;	/* allocated inodes */
223 	__be64		sb_ifree;	/* free inodes */
224 	__be64		sb_fdblocks;	/* free data blocks */
225 	__be64		sb_frextents;	/* free realtime extents */
226 	/*
227 	 * End contiguous fields.
228 	 */
229 	__be64		sb_uquotino;	/* user quota inode */
230 	__be64		sb_gquotino;	/* group quota inode */
231 	__be16		sb_qflags;	/* quota flags */
232 	__u8		sb_flags;	/* misc. flags */
233 	__u8		sb_shared_vn;	/* shared version number */
234 	__be32		sb_inoalignmt;	/* inode chunk alignment, fsblocks */
235 	__be32		sb_unit;	/* stripe or raid unit */
236 	__be32		sb_width;	/* stripe or raid width */
237 	__u8		sb_dirblklog;	/* log2 of dir block size (fsbs) */
238 	__u8		sb_logsectlog;	/* log2 of the log sector size */
239 	__be16		sb_logsectsize;	/* sector size for the log, bytes */
240 	__be32		sb_logsunit;	/* stripe unit size for the log */
241 	__be32		sb_features2;	/* additional feature bits */
242 	/*
243 	 * bad features2 field as a result of failing to pad the sb
244 	 * structure to 64 bits. Some machines will be using this field
245 	 * for features2 bits. Easiest just to mark it bad and not use
246 	 * it for anything else.
247 	 */
248 	__be32		sb_bad_features2;
249 
250 	/* version 5 superblock fields start here */
251 
252 	/* feature masks */
253 	__be32		sb_features_compat;
254 	__be32		sb_features_ro_compat;
255 	__be32		sb_features_incompat;
256 	__be32		sb_features_log_incompat;
257 
258 	__le32		sb_crc;		/* superblock crc */
259 	__be32		sb_spino_align;	/* sparse inode chunk alignment */
260 
261 	__be64		sb_pquotino;	/* project quota inode */
262 	__be64		sb_lsn;		/* last write sequence */
263 	uuid_t		sb_meta_uuid;	/* metadata file system unique id */
264 
265 	/* must be padded to 64 bit alignment */
266 } xfs_dsb_t;
267 
268 
269 /*
270  * Misc. Flags - warning - these will be cleared by xfs_repair unless
271  * a feature bit is set when the flag is used.
272  */
273 #define XFS_SBF_NOFLAGS		0x00	/* no flags set */
274 #define XFS_SBF_READONLY	0x01	/* only read-only mounts allowed */
275 
276 /*
277  * define max. shared version we can interoperate with
278  */
279 #define XFS_SB_MAX_SHARED_VN	0
280 
281 #define	XFS_SB_VERSION_NUM(sbp)	((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
282 
283 /*
284  * The first XFS version we support is a v4 superblock with V2 directories.
285  */
286 static inline bool xfs_sb_good_v4_features(struct xfs_sb *sbp)
287 {
288 	if (!(sbp->sb_versionnum & XFS_SB_VERSION_DIRV2BIT))
289 		return false;
290 	if (!(sbp->sb_versionnum & XFS_SB_VERSION_EXTFLGBIT))
291 		return false;
292 
293 	/* check for unknown features in the fs */
294 	if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) ||
295 	    ((sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT) &&
296 	     (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS)))
297 		return false;
298 
299 	return true;
300 }
301 
302 static inline bool xfs_sb_good_version(struct xfs_sb *sbp)
303 {
304 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5)
305 		return true;
306 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_4)
307 		return xfs_sb_good_v4_features(sbp);
308 	return false;
309 }
310 
311 static inline bool xfs_sb_version_hasrealtime(struct xfs_sb *sbp)
312 {
313 	return sbp->sb_rblocks > 0;
314 }
315 
316 /*
317  * Detect a mismatched features2 field.  Older kernels read/wrote
318  * this into the wrong slot, so to be safe we keep them in sync.
319  */
320 static inline bool xfs_sb_has_mismatched_features2(struct xfs_sb *sbp)
321 {
322 	return sbp->sb_bad_features2 != sbp->sb_features2;
323 }
324 
325 static inline bool xfs_sb_version_hasattr(struct xfs_sb *sbp)
326 {
327 	return (sbp->sb_versionnum & XFS_SB_VERSION_ATTRBIT);
328 }
329 
330 static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
331 {
332 	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
333 }
334 
335 static inline bool xfs_sb_version_hasquota(struct xfs_sb *sbp)
336 {
337 	return (sbp->sb_versionnum & XFS_SB_VERSION_QUOTABIT);
338 }
339 
340 static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
341 {
342 	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
343 }
344 
345 static inline bool xfs_sb_version_hasalign(struct xfs_sb *sbp)
346 {
347 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
348 		(sbp->sb_versionnum & XFS_SB_VERSION_ALIGNBIT));
349 }
350 
351 static inline bool xfs_sb_version_hasdalign(struct xfs_sb *sbp)
352 {
353 	return (sbp->sb_versionnum & XFS_SB_VERSION_DALIGNBIT);
354 }
355 
356 static inline bool xfs_sb_version_haslogv2(struct xfs_sb *sbp)
357 {
358 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
359 	       (sbp->sb_versionnum & XFS_SB_VERSION_LOGV2BIT);
360 }
361 
362 static inline bool xfs_sb_version_hassector(struct xfs_sb *sbp)
363 {
364 	return (sbp->sb_versionnum & XFS_SB_VERSION_SECTORBIT);
365 }
366 
367 static inline bool xfs_sb_version_hasasciici(struct xfs_sb *sbp)
368 {
369 	return (sbp->sb_versionnum & XFS_SB_VERSION_BORGBIT);
370 }
371 
372 static inline bool xfs_sb_version_hasmorebits(struct xfs_sb *sbp)
373 {
374 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
375 	       (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
376 }
377 
378 /*
379  * sb_features2 bit version macros.
380  */
381 static inline bool xfs_sb_version_haslazysbcount(struct xfs_sb *sbp)
382 {
383 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
384 	       (xfs_sb_version_hasmorebits(sbp) &&
385 		(sbp->sb_features2 & XFS_SB_VERSION2_LAZYSBCOUNTBIT));
386 }
387 
388 static inline bool xfs_sb_version_hasattr2(struct xfs_sb *sbp)
389 {
390 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
391 	       (xfs_sb_version_hasmorebits(sbp) &&
392 		(sbp->sb_features2 & XFS_SB_VERSION2_ATTR2BIT));
393 }
394 
395 static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
396 {
397 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
398 	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
399 }
400 
401 static inline void xfs_sb_version_removeattr2(struct xfs_sb *sbp)
402 {
403 	sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT;
404 	if (!sbp->sb_features2)
405 		sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT;
406 }
407 
408 static inline bool xfs_sb_version_hasprojid32bit(struct xfs_sb *sbp)
409 {
410 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
411 	       (xfs_sb_version_hasmorebits(sbp) &&
412 		(sbp->sb_features2 & XFS_SB_VERSION2_PROJID32BIT));
413 }
414 
415 static inline void xfs_sb_version_addprojid32bit(struct xfs_sb *sbp)
416 {
417 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
418 	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
419 }
420 
421 /*
422  * Extended v5 superblock feature masks. These are to be used for new v5
423  * superblock features only.
424  *
425  * Compat features are new features that old kernels will not notice or affect
426  * and so can mount read-write without issues.
427  *
428  * RO-Compat (read only) are features that old kernels can read but will break
429  * if they write. Hence only read-only mounts of such filesystems are allowed on
430  * kernels that don't support the feature bit.
431  *
432  * InCompat features are features which old kernels will not understand and so
433  * must not mount.
434  *
435  * Log-InCompat features are for changes to log formats or new transactions that
436  * can't be replayed on older kernels. The fields are set when the filesystem is
437  * mounted, and a clean unmount clears the fields.
438  */
439 #define XFS_SB_FEAT_COMPAT_ALL 0
440 #define XFS_SB_FEAT_COMPAT_UNKNOWN	~XFS_SB_FEAT_COMPAT_ALL
441 static inline bool
442 xfs_sb_has_compat_feature(
443 	struct xfs_sb	*sbp,
444 	uint32_t	feature)
445 {
446 	return (sbp->sb_features_compat & feature) != 0;
447 }
448 
449 #define XFS_SB_FEAT_RO_COMPAT_FINOBT   (1 << 0)		/* free inode btree */
450 #define XFS_SB_FEAT_RO_COMPAT_RMAPBT   (1 << 1)		/* reverse map btree */
451 #define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
452 #define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3)		/* inobt block counts */
453 #define XFS_SB_FEAT_RO_COMPAT_ALL \
454 		(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
455 		 XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
456 		 XFS_SB_FEAT_RO_COMPAT_REFLINK| \
457 		 XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
458 #define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
459 static inline bool
460 xfs_sb_has_ro_compat_feature(
461 	struct xfs_sb	*sbp,
462 	uint32_t	feature)
463 {
464 	return (sbp->sb_features_ro_compat & feature) != 0;
465 }
466 
467 #define XFS_SB_FEAT_INCOMPAT_FTYPE	(1 << 0)	/* filetype in dirent */
468 #define XFS_SB_FEAT_INCOMPAT_SPINODES	(1 << 1)	/* sparse inode chunks */
469 #define XFS_SB_FEAT_INCOMPAT_META_UUID	(1 << 2)	/* metadata UUID */
470 #define XFS_SB_FEAT_INCOMPAT_BIGTIME	(1 << 3)	/* large timestamps */
471 #define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4)	/* needs xfs_repair */
472 #define XFS_SB_FEAT_INCOMPAT_ALL \
473 		(XFS_SB_FEAT_INCOMPAT_FTYPE|	\
474 		 XFS_SB_FEAT_INCOMPAT_SPINODES|	\
475 		 XFS_SB_FEAT_INCOMPAT_META_UUID| \
476 		 XFS_SB_FEAT_INCOMPAT_BIGTIME| \
477 		 XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR)
478 
479 #define XFS_SB_FEAT_INCOMPAT_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_ALL
480 static inline bool
481 xfs_sb_has_incompat_feature(
482 	struct xfs_sb	*sbp,
483 	uint32_t	feature)
484 {
485 	return (sbp->sb_features_incompat & feature) != 0;
486 }
487 
488 #define XFS_SB_FEAT_INCOMPAT_LOG_ALL 0
489 #define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_LOG_ALL
490 static inline bool
491 xfs_sb_has_incompat_log_feature(
492 	struct xfs_sb	*sbp,
493 	uint32_t	feature)
494 {
495 	return (sbp->sb_features_log_incompat & feature) != 0;
496 }
497 
498 /*
499  * V5 superblock specific feature checks
500  */
501 static inline bool xfs_sb_version_hascrc(struct xfs_sb *sbp)
502 {
503 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
504 }
505 
506 /*
507  * v5 file systems support V3 inodes only, earlier file systems support
508  * v2 and v1 inodes.
509  */
510 static inline bool xfs_sb_version_has_v3inode(struct xfs_sb *sbp)
511 {
512 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
513 }
514 
515 static inline bool xfs_dinode_good_version(struct xfs_sb *sbp,
516 		uint8_t version)
517 {
518 	if (xfs_sb_version_has_v3inode(sbp))
519 		return version == 3;
520 	return version == 1 || version == 2;
521 }
522 
523 static inline bool xfs_sb_version_has_pquotino(struct xfs_sb *sbp)
524 {
525 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
526 }
527 
528 static inline int xfs_sb_version_hasftype(struct xfs_sb *sbp)
529 {
530 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
531 		xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_FTYPE)) ||
532 	       (xfs_sb_version_hasmorebits(sbp) &&
533 		 (sbp->sb_features2 & XFS_SB_VERSION2_FTYPE));
534 }
535 
536 static inline bool xfs_sb_version_hasfinobt(xfs_sb_t *sbp)
537 {
538 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
539 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_FINOBT);
540 }
541 
542 static inline bool xfs_sb_version_hassparseinodes(struct xfs_sb *sbp)
543 {
544 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
545 		xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_SPINODES);
546 }
547 
548 /*
549  * XFS_SB_FEAT_INCOMPAT_META_UUID indicates that the metadata UUID
550  * is stored separately from the user-visible UUID; this allows the
551  * user-visible UUID to be changed on V5 filesystems which have a
552  * filesystem UUID stamped into every piece of metadata.
553  */
554 static inline bool xfs_sb_version_hasmetauuid(struct xfs_sb *sbp)
555 {
556 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
557 		(sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_META_UUID);
558 }
559 
560 static inline bool xfs_sb_version_hasrmapbt(struct xfs_sb *sbp)
561 {
562 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
563 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_RMAPBT);
564 }
565 
566 static inline bool xfs_sb_version_hasreflink(struct xfs_sb *sbp)
567 {
568 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
569 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_REFLINK);
570 }
571 
572 static inline bool xfs_sb_version_hasbigtime(struct xfs_sb *sbp)
573 {
574 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
575 		(sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_BIGTIME);
576 }
577 
578 /*
579  * Inode btree block counter.  We record the number of inobt and finobt blocks
580  * in the AGI header so that we can skip the finobt walk at mount time when
581  * setting up per-AG reservations.
582  */
583 static inline bool xfs_sb_version_hasinobtcounts(struct xfs_sb *sbp)
584 {
585 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
586 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_INOBTCNT);
587 }
588 
589 static inline bool xfs_sb_version_needsrepair(struct xfs_sb *sbp)
590 {
591 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
592 		(sbp->sb_features_incompat & XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR);
593 }
594 
595 /*
596  * end of superblock version macros
597  */
598 
599 static inline bool
600 xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
601 {
602 	return (ino == sbp->sb_uquotino ||
603 		ino == sbp->sb_gquotino ||
604 		ino == sbp->sb_pquotino);
605 }
606 
607 #define XFS_SB_DADDR		((xfs_daddr_t)0) /* daddr in filesystem/ag */
608 #define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
609 
610 #define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
611 #define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
612 			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
613 #define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
614 			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
615 
616 /*
617  * File system sector to basic block conversions.
618  */
619 #define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)
620 
621 /*
622  * File system block to basic block conversions.
623  */
624 #define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
625 #define	XFS_BB_TO_FSB(mp,bb)	\
626 	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
627 #define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)
628 
629 /*
630  * File system block to byte conversions.
631  */
632 #define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
633 #define XFS_B_TO_FSB(mp,b)	\
634 	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
635 #define XFS_B_TO_FSBT(mp,b)	(((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
636 
637 /*
638  * Allocation group header
639  *
640  * This is divided into three structures, placed in sequential 512-byte
641  * buffers after a copy of the superblock (also in a 512-byte buffer).
642  */
643 #define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
644 #define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
645 #define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
646 #define	XFS_AGF_VERSION	1
647 #define	XFS_AGI_VERSION	1
648 
649 #define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
650 #define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
651 
652 /*
653  * Btree number 0 is bno, 1 is cnt, 2 is rmap. This value gives the size of the
654  * arrays below.
655  */
656 #define	XFS_BTNUM_AGF	((int)XFS_BTNUM_RMAPi + 1)
657 
658 /*
659  * The second word of agf_levels in the first a.g. overlaps the EFS
660  * superblock's magic number.  Since the magic numbers valid for EFS
661  * are > 64k, our value cannot be confused for an EFS superblock's.
662  */
663 
664 typedef struct xfs_agf {
665 	/*
666 	 * Common allocation group header information
667 	 */
668 	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
669 	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
670 	__be32		agf_seqno;	/* sequence # starting from 0 */
671 	__be32		agf_length;	/* size in blocks of a.g. */
672 	/*
673 	 * Freespace and rmap information
674 	 */
675 	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
676 	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
677 
678 	__be32		agf_flfirst;	/* first freelist block's index */
679 	__be32		agf_fllast;	/* last freelist block's index */
680 	__be32		agf_flcount;	/* count of blocks in freelist */
681 	__be32		agf_freeblks;	/* total free blocks */
682 
683 	__be32		agf_longest;	/* longest free space */
684 	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
685 	uuid_t		agf_uuid;	/* uuid of filesystem */
686 
687 	__be32		agf_rmap_blocks;	/* rmapbt blocks used */
688 	__be32		agf_refcount_blocks;	/* refcountbt blocks used */
689 
690 	__be32		agf_refcount_root;	/* refcount tree root block */
691 	__be32		agf_refcount_level;	/* refcount btree levels */
692 
693 	/*
694 	 * reserve some contiguous space for future logged fields before we add
695 	 * the unlogged fields. This makes the range logging via flags and
696 	 * structure offsets much simpler.
697 	 */
698 	__be64		agf_spare64[14];
699 
700 	/* unlogged fields, written during buffer writeback. */
701 	__be64		agf_lsn;	/* last write sequence */
702 	__be32		agf_crc;	/* crc of agf sector */
703 	__be32		agf_spare2;
704 
705 	/* structure must be padded to 64 bit alignment */
706 } xfs_agf_t;
707 
708 #define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
709 
710 #define	XFS_AGF_MAGICNUM	0x00000001
711 #define	XFS_AGF_VERSIONNUM	0x00000002
712 #define	XFS_AGF_SEQNO		0x00000004
713 #define	XFS_AGF_LENGTH		0x00000008
714 #define	XFS_AGF_ROOTS		0x00000010
715 #define	XFS_AGF_LEVELS		0x00000020
716 #define	XFS_AGF_FLFIRST		0x00000040
717 #define	XFS_AGF_FLLAST		0x00000080
718 #define	XFS_AGF_FLCOUNT		0x00000100
719 #define	XFS_AGF_FREEBLKS	0x00000200
720 #define	XFS_AGF_LONGEST		0x00000400
721 #define	XFS_AGF_BTREEBLKS	0x00000800
722 #define	XFS_AGF_UUID		0x00001000
723 #define	XFS_AGF_RMAP_BLOCKS	0x00002000
724 #define	XFS_AGF_REFCOUNT_BLOCKS	0x00004000
725 #define	XFS_AGF_REFCOUNT_ROOT	0x00008000
726 #define	XFS_AGF_REFCOUNT_LEVEL	0x00010000
727 #define	XFS_AGF_SPARE64		0x00020000
728 #define	XFS_AGF_NUM_BITS	18
729 #define	XFS_AGF_ALL_BITS	((1 << XFS_AGF_NUM_BITS) - 1)
730 
731 #define XFS_AGF_FLAGS \
732 	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
733 	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
734 	{ XFS_AGF_SEQNO,	"SEQNO" }, \
735 	{ XFS_AGF_LENGTH,	"LENGTH" }, \
736 	{ XFS_AGF_ROOTS,	"ROOTS" }, \
737 	{ XFS_AGF_LEVELS,	"LEVELS" }, \
738 	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
739 	{ XFS_AGF_FLLAST,	"FLLAST" }, \
740 	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
741 	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
742 	{ XFS_AGF_LONGEST,	"LONGEST" }, \
743 	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
744 	{ XFS_AGF_UUID,		"UUID" }, \
745 	{ XFS_AGF_RMAP_BLOCKS,	"RMAP_BLOCKS" }, \
746 	{ XFS_AGF_REFCOUNT_BLOCKS,	"REFCOUNT_BLOCKS" }, \
747 	{ XFS_AGF_REFCOUNT_ROOT,	"REFCOUNT_ROOT" }, \
748 	{ XFS_AGF_REFCOUNT_LEVEL,	"REFCOUNT_LEVEL" }, \
749 	{ XFS_AGF_SPARE64,	"SPARE64" }
750 
751 /* disk block (xfs_daddr_t) in the AG */
752 #define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
753 #define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
754 
755 /*
756  * Size of the unlinked inode hash table in the agi.
757  */
758 #define	XFS_AGI_UNLINKED_BUCKETS	64
759 
760 typedef struct xfs_agi {
761 	/*
762 	 * Common allocation group header information
763 	 */
764 	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
765 	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
766 	__be32		agi_seqno;	/* sequence # starting from 0 */
767 	__be32		agi_length;	/* size in blocks of a.g. */
768 	/*
769 	 * Inode information
770 	 * Inodes are mapped by interpreting the inode number, so no
771 	 * mapping data is needed here.
772 	 */
773 	__be32		agi_count;	/* count of allocated inodes */
774 	__be32		agi_root;	/* root of inode btree */
775 	__be32		agi_level;	/* levels in inode btree */
776 	__be32		agi_freecount;	/* number of free inodes */
777 
778 	__be32		agi_newino;	/* new inode just allocated */
779 	__be32		agi_dirino;	/* last directory inode chunk */
780 	/*
781 	 * Hash table of inodes which have been unlinked but are
782 	 * still being referenced.
783 	 */
784 	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
785 	/*
786 	 * This marks the end of logging region 1 and start of logging region 2.
787 	 */
788 	uuid_t		agi_uuid;	/* uuid of filesystem */
789 	__be32		agi_crc;	/* crc of agi sector */
790 	__be32		agi_pad32;
791 	__be64		agi_lsn;	/* last write sequence */
792 
793 	__be32		agi_free_root; /* root of the free inode btree */
794 	__be32		agi_free_level;/* levels in free inode btree */
795 
796 	__be32		agi_iblocks;	/* inobt blocks used */
797 	__be32		agi_fblocks;	/* finobt blocks used */
798 
799 	/* structure must be padded to 64 bit alignment */
800 } xfs_agi_t;
801 
802 #define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
803 
804 #define	XFS_AGI_MAGICNUM	(1 << 0)
805 #define	XFS_AGI_VERSIONNUM	(1 << 1)
806 #define	XFS_AGI_SEQNO		(1 << 2)
807 #define	XFS_AGI_LENGTH		(1 << 3)
808 #define	XFS_AGI_COUNT		(1 << 4)
809 #define	XFS_AGI_ROOT		(1 << 5)
810 #define	XFS_AGI_LEVEL		(1 << 6)
811 #define	XFS_AGI_FREECOUNT	(1 << 7)
812 #define	XFS_AGI_NEWINO		(1 << 8)
813 #define	XFS_AGI_DIRINO		(1 << 9)
814 #define	XFS_AGI_UNLINKED	(1 << 10)
815 #define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
816 #define	XFS_AGI_ALL_BITS_R1	((1 << XFS_AGI_NUM_BITS_R1) - 1)
817 #define	XFS_AGI_FREE_ROOT	(1 << 11)
818 #define	XFS_AGI_FREE_LEVEL	(1 << 12)
819 #define	XFS_AGI_IBLOCKS		(1 << 13) /* both inobt/finobt block counters */
820 #define	XFS_AGI_NUM_BITS_R2	14
821 
822 /* disk block (xfs_daddr_t) in the AG */
823 #define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
824 #define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
825 
826 /*
827  * The third a.g. block contains the a.g. freelist, an array
828  * of block pointers to blocks owned by the allocation btree code.
829  */
830 #define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
831 #define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
832 #define	XFS_BUF_TO_AGFL(bp)	((struct xfs_agfl *)((bp)->b_addr))
833 
834 struct xfs_agfl {
835 	__be32		agfl_magicnum;
836 	__be32		agfl_seqno;
837 	uuid_t		agfl_uuid;
838 	__be64		agfl_lsn;
839 	__be32		agfl_crc;
840 } __attribute__((packed));
841 
842 #define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
843 
844 #define XFS_AGB_TO_FSB(mp,agno,agbno)	\
845 	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
846 #define	XFS_FSB_TO_AGNO(mp,fsbno)	\
847 	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
848 #define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
849 	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
850 #define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
851 	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
852 		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
853 #define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
854 
855 /*
856  * For checking for bad ranges of xfs_daddr_t's, covering multiple
857  * allocation groups or a single xfs_daddr_t that's a superblock copy.
858  */
859 #define	XFS_AG_CHECK_DADDR(mp,d,len)	\
860 	((len) == 1 ? \
861 	    ASSERT((d) == XFS_SB_DADDR || \
862 		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
863 	    ASSERT(xfs_daddr_to_agno(mp, d) == \
864 		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
865 
866 /*
867  * XFS Timestamps
868  * ==============
869  *
870  * Traditional ondisk inode timestamps consist of signed 32-bit counters for
871  * seconds and nanoseconds; time zero is the Unix epoch, Jan  1 00:00:00 UTC
872  * 1970, which means that the timestamp epoch is the same as the Unix epoch.
873  * Therefore, the ondisk min and max defined here can be used directly to
874  * constrain the incore timestamps on a Unix system.  Note that we actually
875  * encode a __be64 value on disk.
876  *
877  * When the bigtime feature is enabled, ondisk inode timestamps become an
878  * unsigned 64-bit nanoseconds counter.  This means that the bigtime inode
879  * timestamp epoch is the start of the classic timestamp range, which is
880  * Dec 31 20:45:52 UTC 1901.  Because the epochs are not the same, callers
881  * /must/ use the bigtime conversion functions when encoding and decoding raw
882  * timestamps.
883  */
884 typedef __be64 xfs_timestamp_t;
885 
886 /* Legacy timestamp encoding format. */
887 struct xfs_legacy_timestamp {
888 	__be32		t_sec;		/* timestamp seconds */
889 	__be32		t_nsec;		/* timestamp nanoseconds */
890 };
891 
892 /*
893  * Smallest possible ondisk seconds value with traditional timestamps.  This
894  * corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
895  */
896 #define XFS_LEGACY_TIME_MIN	((int64_t)S32_MIN)
897 
898 /*
899  * Largest possible ondisk seconds value with traditional timestamps.  This
900  * corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
901  */
902 #define XFS_LEGACY_TIME_MAX	((int64_t)S32_MAX)
903 
904 /*
905  * Smallest possible ondisk seconds value with bigtime timestamps.  This
906  * corresponds (after conversion to a Unix timestamp) with the traditional
907  * minimum timestamp of Dec 13 20:45:52 UTC 1901.
908  */
909 #define XFS_BIGTIME_TIME_MIN	((int64_t)0)
910 
911 /*
912  * Largest supported ondisk seconds value with bigtime timestamps.  This
913  * corresponds (after conversion to a Unix timestamp) with an incore timestamp
914  * of Jul  2 20:20:24 UTC 2486.
915  *
916  * We round down the ondisk limit so that the bigtime quota and inode max
917  * timestamps will be the same.
918  */
919 #define XFS_BIGTIME_TIME_MAX	((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
920 
921 /*
922  * Bigtime epoch is set exactly to the minimum time value that a traditional
923  * 32-bit timestamp can represent when using the Unix epoch as a reference.
924  * Hence the Unix epoch is at a fixed offset into the supported bigtime
925  * timestamp range.
926  *
927  * The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
928  * timestamp can represent so we will not lose any fidelity in converting
929  * to/from unix and bigtime timestamps.
930  *
931  * The following conversion factor converts a seconds counter from the Unix
932  * epoch to the bigtime epoch.
933  */
934 #define XFS_BIGTIME_EPOCH_OFFSET	(-(int64_t)S32_MIN)
935 
936 /* Convert a timestamp from the Unix epoch to the bigtime epoch. */
937 static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
938 {
939 	return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
940 }
941 
942 /* Convert a timestamp from the bigtime epoch to the Unix epoch. */
943 static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
944 {
945 	return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
946 }
947 
948 /*
949  * On-disk inode structure.
950  *
951  * This is just the header or "dinode core", the inode is expanded to fill a
952  * variable size the leftover area split into a data and an attribute fork.
953  * The format of the data and attribute fork depends on the format of the
954  * inode as indicated by di_format and di_aformat.  To access the data and
955  * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
956  * below.
957  *
958  * There is a very similar struct icdinode in xfs_inode which matches the
959  * layout of the first 96 bytes of this structure, but is kept in native
960  * format instead of big endian.
961  *
962  * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
963  * padding field for v3 inodes.
964  */
965 #define	XFS_DINODE_MAGIC		0x494e	/* 'IN' */
966 typedef struct xfs_dinode {
967 	__be16		di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
968 	__be16		di_mode;	/* mode and type of file */
969 	__u8		di_version;	/* inode version */
970 	__u8		di_format;	/* format of di_c data */
971 	__be16		di_onlink;	/* old number of links to file */
972 	__be32		di_uid;		/* owner's user id */
973 	__be32		di_gid;		/* owner's group id */
974 	__be32		di_nlink;	/* number of links to file */
975 	__be16		di_projid_lo;	/* lower part of owner's project id */
976 	__be16		di_projid_hi;	/* higher part owner's project id */
977 	__u8		di_pad[6];	/* unused, zeroed space */
978 	__be16		di_flushiter;	/* incremented on flush */
979 	xfs_timestamp_t	di_atime;	/* time last accessed */
980 	xfs_timestamp_t	di_mtime;	/* time last modified */
981 	xfs_timestamp_t	di_ctime;	/* time created/inode modified */
982 	__be64		di_size;	/* number of bytes in file */
983 	__be64		di_nblocks;	/* # of direct & btree blocks used */
984 	__be32		di_extsize;	/* basic/minimum extent size for file */
985 	__be32		di_nextents;	/* number of extents in data fork */
986 	__be16		di_anextents;	/* number of extents in attribute fork*/
987 	__u8		di_forkoff;	/* attr fork offs, <<3 for 64b align */
988 	__s8		di_aformat;	/* format of attr fork's data */
989 	__be32		di_dmevmask;	/* DMIG event mask */
990 	__be16		di_dmstate;	/* DMIG state info */
991 	__be16		di_flags;	/* random flags, XFS_DIFLAG_... */
992 	__be32		di_gen;		/* generation number */
993 
994 	/* di_next_unlinked is the only non-core field in the old dinode */
995 	__be32		di_next_unlinked;/* agi unlinked list ptr */
996 
997 	/* start of the extended dinode, writable fields */
998 	__le32		di_crc;		/* CRC of the inode */
999 	__be64		di_changecount;	/* number of attribute changes */
1000 	__be64		di_lsn;		/* flush sequence */
1001 	__be64		di_flags2;	/* more random flags */
1002 	__be32		di_cowextsize;	/* basic cow extent size for file */
1003 	__u8		di_pad2[12];	/* more padding for future expansion */
1004 
1005 	/* fields only written to during inode creation */
1006 	xfs_timestamp_t	di_crtime;	/* time created */
1007 	__be64		di_ino;		/* inode number */
1008 	uuid_t		di_uuid;	/* UUID of the filesystem */
1009 
1010 	/* structure must be padded to 64 bit alignment */
1011 } xfs_dinode_t;
1012 
1013 #define XFS_DINODE_CRC_OFF	offsetof(struct xfs_dinode, di_crc)
1014 
1015 #define DI_MAX_FLUSH 0xffff
1016 
1017 /*
1018  * Size of the core inode on disk.  Version 1 and 2 inodes have
1019  * the same size, but version 3 has grown a few additional fields.
1020  */
1021 static inline uint xfs_dinode_size(int version)
1022 {
1023 	if (version == 3)
1024 		return sizeof(struct xfs_dinode);
1025 	return offsetof(struct xfs_dinode, di_crc);
1026 }
1027 
1028 /*
1029  * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
1030  * Since the pathconf interface is signed, we use 2^31 - 1 instead.
1031  */
1032 #define	XFS_MAXLINK		((1U << 31) - 1U)
1033 
1034 /*
1035  * Values for di_format
1036  *
1037  * This enum is used in string mapping in xfs_trace.h; please keep the
1038  * TRACE_DEFINE_ENUMs for it up to date.
1039  */
1040 enum xfs_dinode_fmt {
1041 	XFS_DINODE_FMT_DEV,		/* xfs_dev_t */
1042 	XFS_DINODE_FMT_LOCAL,		/* bulk data */
1043 	XFS_DINODE_FMT_EXTENTS,		/* struct xfs_bmbt_rec */
1044 	XFS_DINODE_FMT_BTREE,		/* struct xfs_bmdr_block */
1045 	XFS_DINODE_FMT_UUID		/* added long ago, but never used */
1046 };
1047 
1048 #define XFS_INODE_FORMAT_STR \
1049 	{ XFS_DINODE_FMT_DEV,		"dev" }, \
1050 	{ XFS_DINODE_FMT_LOCAL,		"local" }, \
1051 	{ XFS_DINODE_FMT_EXTENTS,	"extent" }, \
1052 	{ XFS_DINODE_FMT_BTREE,		"btree" }, \
1053 	{ XFS_DINODE_FMT_UUID,		"uuid" }
1054 
1055 /*
1056  * Inode minimum and maximum sizes.
1057  */
1058 #define	XFS_DINODE_MIN_LOG	8
1059 #define	XFS_DINODE_MAX_LOG	11
1060 #define	XFS_DINODE_MIN_SIZE	(1 << XFS_DINODE_MIN_LOG)
1061 #define	XFS_DINODE_MAX_SIZE	(1 << XFS_DINODE_MAX_LOG)
1062 
1063 /*
1064  * Inode size for given fs.
1065  */
1066 #define XFS_DINODE_SIZE(sbp) \
1067 	(xfs_sb_version_has_v3inode(sbp) ? \
1068 		sizeof(struct xfs_dinode) : \
1069 		offsetof(struct xfs_dinode, di_crc))
1070 #define XFS_LITINO(mp) \
1071 	((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(&(mp)->m_sb))
1072 
1073 /*
1074  * Inode data & attribute fork sizes, per inode.
1075  */
1076 #define XFS_DFORK_BOFF(dip)		((int)((dip)->di_forkoff << 3))
1077 
1078 #define XFS_DFORK_DSIZE(dip,mp) \
1079 	((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
1080 #define XFS_DFORK_ASIZE(dip,mp) \
1081 	((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
1082 #define XFS_DFORK_SIZE(dip,mp,w) \
1083 	((w) == XFS_DATA_FORK ? \
1084 		XFS_DFORK_DSIZE(dip, mp) : \
1085 		XFS_DFORK_ASIZE(dip, mp))
1086 
1087 #define XFS_DFORK_MAXEXT(dip, mp, w) \
1088 	(XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
1089 
1090 /*
1091  * Return pointers to the data or attribute forks.
1092  */
1093 #define XFS_DFORK_DPTR(dip) \
1094 	((char *)dip + xfs_dinode_size(dip->di_version))
1095 #define XFS_DFORK_APTR(dip)	\
1096 	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
1097 #define XFS_DFORK_PTR(dip,w)	\
1098 	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
1099 
1100 #define XFS_DFORK_FORMAT(dip,w) \
1101 	((w) == XFS_DATA_FORK ? \
1102 		(dip)->di_format : \
1103 		(dip)->di_aformat)
1104 #define XFS_DFORK_NEXTENTS(dip,w) \
1105 	((w) == XFS_DATA_FORK ? \
1106 		be32_to_cpu((dip)->di_nextents) : \
1107 		be16_to_cpu((dip)->di_anextents))
1108 
1109 /*
1110  * For block and character special files the 32bit dev_t is stored at the
1111  * beginning of the data fork.
1112  */
1113 static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
1114 {
1115 	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
1116 }
1117 
1118 static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
1119 {
1120 	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
1121 }
1122 
1123 /*
1124  * Values for di_flags
1125  */
1126 #define XFS_DIFLAG_REALTIME_BIT  0	/* file's blocks come from rt area */
1127 #define XFS_DIFLAG_PREALLOC_BIT  1	/* file space has been preallocated */
1128 #define XFS_DIFLAG_NEWRTBM_BIT   2	/* for rtbitmap inode, new format */
1129 #define XFS_DIFLAG_IMMUTABLE_BIT 3	/* inode is immutable */
1130 #define XFS_DIFLAG_APPEND_BIT    4	/* inode is append-only */
1131 #define XFS_DIFLAG_SYNC_BIT      5	/* inode is written synchronously */
1132 #define XFS_DIFLAG_NOATIME_BIT   6	/* do not update atime */
1133 #define XFS_DIFLAG_NODUMP_BIT    7	/* do not dump */
1134 #define XFS_DIFLAG_RTINHERIT_BIT 8	/* create with realtime bit set */
1135 #define XFS_DIFLAG_PROJINHERIT_BIT   9	/* create with parents projid */
1136 #define XFS_DIFLAG_NOSYMLINKS_BIT   10	/* disallow symlink creation */
1137 #define XFS_DIFLAG_EXTSIZE_BIT      11	/* inode extent size allocator hint */
1138 #define XFS_DIFLAG_EXTSZINHERIT_BIT 12	/* inherit inode extent size */
1139 #define XFS_DIFLAG_NODEFRAG_BIT     13	/* do not reorganize/defragment */
1140 #define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
1141 /* Do not use bit 15, di_flags is legacy and unchanging now */
1142 
1143 #define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
1144 #define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
1145 #define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
1146 #define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
1147 #define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
1148 #define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
1149 #define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
1150 #define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
1151 #define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
1152 #define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
1153 #define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
1154 #define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
1155 #define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
1156 #define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
1157 #define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
1158 
1159 #define XFS_DIFLAG_ANY \
1160 	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
1161 	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
1162 	 XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
1163 	 XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
1164 	 XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
1165 
1166 /*
1167  * Values for di_flags2 These start by being exposed to userspace in the upper
1168  * 16 bits of the XFS_XFLAG_s range.
1169  */
1170 #define XFS_DIFLAG2_DAX_BIT	0	/* use DAX for this inode */
1171 #define XFS_DIFLAG2_REFLINK_BIT	1	/* file's blocks may be shared */
1172 #define XFS_DIFLAG2_COWEXTSIZE_BIT   2  /* copy on write extent size hint */
1173 #define XFS_DIFLAG2_BIGTIME_BIT	3	/* big timestamps */
1174 
1175 #define XFS_DIFLAG2_DAX		(1 << XFS_DIFLAG2_DAX_BIT)
1176 #define XFS_DIFLAG2_REFLINK     (1 << XFS_DIFLAG2_REFLINK_BIT)
1177 #define XFS_DIFLAG2_COWEXTSIZE  (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
1178 #define XFS_DIFLAG2_BIGTIME	(1 << XFS_DIFLAG2_BIGTIME_BIT)
1179 
1180 #define XFS_DIFLAG2_ANY \
1181 	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
1182 	 XFS_DIFLAG2_BIGTIME)
1183 
1184 static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
1185 {
1186 	return dip->di_version >= 3 &&
1187 	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
1188 }
1189 
1190 /*
1191  * Inode number format:
1192  * low inopblog bits - offset in block
1193  * next agblklog bits - block number in ag
1194  * next agno_log bits - ag number
1195  * high agno_log-agblklog-inopblog bits - 0
1196  */
1197 #define	XFS_INO_MASK(k)			(uint32_t)((1ULL << (k)) - 1)
1198 #define	XFS_INO_OFFSET_BITS(mp)		(mp)->m_sb.sb_inopblog
1199 #define	XFS_INO_AGBNO_BITS(mp)		(mp)->m_sb.sb_agblklog
1200 #define	XFS_INO_AGINO_BITS(mp)		((mp)->m_ino_geo.agino_log)
1201 #define	XFS_INO_AGNO_BITS(mp)		(mp)->m_agno_log
1202 #define	XFS_INO_BITS(mp)		\
1203 	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1204 #define	XFS_INO_TO_AGNO(mp,i)		\
1205 	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1206 #define	XFS_INO_TO_AGINO(mp,i)		\
1207 	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1208 #define	XFS_INO_TO_AGBNO(mp,i)		\
1209 	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1210 		XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1211 #define	XFS_INO_TO_OFFSET(mp,i)		\
1212 	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1213 #define	XFS_INO_TO_FSB(mp,i)		\
1214 	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1215 #define	XFS_AGINO_TO_INO(mp,a,i)	\
1216 	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1217 #define	XFS_AGINO_TO_AGBNO(mp,i)	((i) >> XFS_INO_OFFSET_BITS(mp))
1218 #define	XFS_AGINO_TO_OFFSET(mp,i)	\
1219 	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1220 #define	XFS_OFFBNO_TO_AGINO(mp,b,o)	\
1221 	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1222 #define	XFS_FSB_TO_INO(mp, b)	((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1223 #define	XFS_AGB_TO_AGINO(mp, b)	((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1224 
1225 #define	XFS_MAXINUMBER		((xfs_ino_t)((1ULL << 56) - 1ULL))
1226 #define	XFS_MAXINUMBER_32	((xfs_ino_t)((1ULL << 32) - 1ULL))
1227 
1228 /*
1229  * RealTime Device format definitions
1230  */
1231 
1232 /* Min and max rt extent sizes, specified in bytes */
1233 #define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
1234 #define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
1235 #define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */
1236 
1237 #define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
1238 #define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
1239 #define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
1240 #define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
1241 
1242 /*
1243  * RT Summary and bit manipulation macros.
1244  */
1245 #define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
1246 #define	XFS_SUMOFFSTOBLOCK(mp,s)	\
1247 	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
1248 #define	XFS_SUMPTR(mp,bp,so)	\
1249 	((xfs_suminfo_t *)((bp)->b_addr + \
1250 		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
1251 
1252 #define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
1253 #define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
1254 #define	XFS_BITTOWORD(mp,bi)	\
1255 	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
1256 
1257 #define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
1258 #define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
1259 
1260 #define	XFS_RTLOBIT(w)	xfs_lowbit32(w)
1261 #define	XFS_RTHIBIT(w)	xfs_highbit32(w)
1262 
1263 #define	XFS_RTBLOCKLOG(b)	xfs_highbit64(b)
1264 
1265 /*
1266  * Dquot and dquot block format definitions
1267  */
1268 #define XFS_DQUOT_MAGIC		0x4451		/* 'DQ' */
1269 #define XFS_DQUOT_VERSION	(uint8_t)0x01	/* latest version number */
1270 
1271 #define XFS_DQTYPE_USER		0x01		/* user dquot record */
1272 #define XFS_DQTYPE_PROJ		0x02		/* project dquot record */
1273 #define XFS_DQTYPE_GROUP	0x04		/* group dquot record */
1274 #define XFS_DQTYPE_BIGTIME	0x80		/* large expiry timestamps */
1275 
1276 /* bitmask to determine if this is a user/group/project dquot */
1277 #define XFS_DQTYPE_REC_MASK	(XFS_DQTYPE_USER | \
1278 				 XFS_DQTYPE_PROJ | \
1279 				 XFS_DQTYPE_GROUP)
1280 
1281 #define XFS_DQTYPE_ANY		(XFS_DQTYPE_REC_MASK | \
1282 				 XFS_DQTYPE_BIGTIME)
1283 
1284 /*
1285  * XFS Quota Timers
1286  * ================
1287  *
1288  * Traditional quota grace period expiration timers are an unsigned 32-bit
1289  * seconds counter; time zero is the Unix epoch, Jan  1 00:00:01 UTC 1970.
1290  * Note that an expiration value of zero means that the quota limit has not
1291  * been reached, and therefore no expiration has been set.  Therefore, the
1292  * ondisk min and max defined here can be used directly to constrain the incore
1293  * quota expiration timestamps on a Unix system.
1294  *
1295  * When bigtime is enabled, we trade two bits of precision to expand the
1296  * expiration timeout range to match that of big inode timestamps.  The min and
1297  * max recorded here are the on-disk limits, not a Unix timestamp.
1298  *
1299  * The grace period for each quota type is stored in the root dquot (id = 0)
1300  * and is applied to a non-root dquot when it exceeds the soft or hard limits.
1301  * The length of quota grace periods are unsigned 32-bit quantities measured in
1302  * units of seconds.  A value of zero means to use the default period.
1303  */
1304 
1305 /*
1306  * Smallest possible ondisk quota expiration value with traditional timestamps.
1307  * This corresponds exactly with the incore expiration Jan  1 00:00:01 UTC 1970.
1308  */
1309 #define XFS_DQ_LEGACY_EXPIRY_MIN	((int64_t)1)
1310 
1311 /*
1312  * Largest possible ondisk quota expiration value with traditional timestamps.
1313  * This corresponds exactly with the incore expiration Feb  7 06:28:15 UTC 2106.
1314  */
1315 #define XFS_DQ_LEGACY_EXPIRY_MAX	((int64_t)U32_MAX)
1316 
1317 /*
1318  * Smallest possible ondisk quota expiration value with bigtime timestamps.
1319  * This corresponds (after conversion to a Unix timestamp) with the incore
1320  * expiration of Jan  1 00:00:04 UTC 1970.
1321  */
1322 #define XFS_DQ_BIGTIME_EXPIRY_MIN	(XFS_DQ_LEGACY_EXPIRY_MIN)
1323 
1324 /*
1325  * Largest supported ondisk quota expiration value with bigtime timestamps.
1326  * This corresponds (after conversion to a Unix timestamp) with an incore
1327  * expiration of Jul  2 20:20:24 UTC 2486.
1328  *
1329  * The ondisk field supports values up to -1U, which corresponds to an incore
1330  * expiration in 2514.  This is beyond the maximum the bigtime inode timestamp,
1331  * so we cap the maximum bigtime quota expiration to the max inode timestamp.
1332  */
1333 #define XFS_DQ_BIGTIME_EXPIRY_MAX	((int64_t)4074815106U)
1334 
1335 /*
1336  * The following conversion factors assist in converting a quota expiration
1337  * timestamp between the incore and ondisk formats.
1338  */
1339 #define XFS_DQ_BIGTIME_SHIFT	(2)
1340 #define XFS_DQ_BIGTIME_SLACK	((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
1341 
1342 /* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
1343 static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
1344 {
1345 	/*
1346 	 * Round the expiration timestamp up to the nearest bigtime timestamp
1347 	 * that we can store, to give users the most time to fix problems.
1348 	 */
1349 	return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
1350 			XFS_DQ_BIGTIME_SHIFT;
1351 }
1352 
1353 /* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
1354 static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
1355 {
1356 	return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
1357 }
1358 
1359 /*
1360  * Default quota grace periods, ranging from zero (use the compiled defaults)
1361  * to ~136 years.  These are applied to a non-root dquot that has exceeded
1362  * either limit.
1363  */
1364 #define XFS_DQ_GRACE_MIN		((int64_t)0)
1365 #define XFS_DQ_GRACE_MAX		((int64_t)U32_MAX)
1366 
1367 /*
1368  * This is the main portion of the on-disk representation of quota information
1369  * for a user.  We pad this with some more expansion room to construct the on
1370  * disk structure.
1371  */
1372 struct xfs_disk_dquot {
1373 	__be16		d_magic;	/* dquot magic = XFS_DQUOT_MAGIC */
1374 	__u8		d_version;	/* dquot version */
1375 	__u8		d_type;		/* XFS_DQTYPE_USER/PROJ/GROUP */
1376 	__be32		d_id;		/* user,project,group id */
1377 	__be64		d_blk_hardlimit;/* absolute limit on disk blks */
1378 	__be64		d_blk_softlimit;/* preferred limit on disk blks */
1379 	__be64		d_ino_hardlimit;/* maximum # allocated inodes */
1380 	__be64		d_ino_softlimit;/* preferred inode limit */
1381 	__be64		d_bcount;	/* disk blocks owned by the user */
1382 	__be64		d_icount;	/* inodes owned by the user */
1383 	__be32		d_itimer;	/* zero if within inode limits if not,
1384 					   this is when we refuse service */
1385 	__be32		d_btimer;	/* similar to above; for disk blocks */
1386 	__be16		d_iwarns;	/* warnings issued wrt num inodes */
1387 	__be16		d_bwarns;	/* warnings issued wrt disk blocks */
1388 	__be32		d_pad0;		/* 64 bit align */
1389 	__be64		d_rtb_hardlimit;/* absolute limit on realtime blks */
1390 	__be64		d_rtb_softlimit;/* preferred limit on RT disk blks */
1391 	__be64		d_rtbcount;	/* realtime blocks owned */
1392 	__be32		d_rtbtimer;	/* similar to above; for RT disk blocks */
1393 	__be16		d_rtbwarns;	/* warnings issued wrt RT disk blocks */
1394 	__be16		d_pad;
1395 };
1396 
1397 /*
1398  * This is what goes on disk. This is separated from the xfs_disk_dquot because
1399  * carrying the unnecessary padding would be a waste of memory.
1400  */
1401 typedef struct xfs_dqblk {
1402 	struct xfs_disk_dquot	dd_diskdq; /* portion living incore as well */
1403 	char			dd_fill[4];/* filling for posterity */
1404 
1405 	/*
1406 	 * These two are only present on filesystems with the CRC bits set.
1407 	 */
1408 	__be32		  dd_crc;	/* checksum */
1409 	__be64		  dd_lsn;	/* last modification in log */
1410 	uuid_t		  dd_uuid;	/* location information */
1411 } xfs_dqblk_t;
1412 
1413 #define XFS_DQUOT_CRC_OFF	offsetof(struct xfs_dqblk, dd_crc)
1414 
1415 /*
1416  * This defines the unit of allocation of dquots.
1417  *
1418  * Currently, it is just one file system block, and a 4K blk contains 30
1419  * (136 * 30 = 4080) dquots. It's probably not worth trying to make
1420  * this more dynamic.
1421  *
1422  * However, if this number is changed, we have to make sure that we don't
1423  * implicitly assume that we do allocations in chunks of a single filesystem
1424  * block in the dquot/xqm code.
1425  *
1426  * This is part of the ondisk format because the structure size is not a power
1427  * of two, which leaves slack at the end of the disk block.
1428  */
1429 #define XFS_DQUOT_CLUSTER_SIZE_FSB	(xfs_filblks_t)1
1430 
1431 /*
1432  * Remote symlink format and access functions.
1433  */
1434 #define XFS_SYMLINK_MAGIC	0x58534c4d	/* XSLM */
1435 
1436 struct xfs_dsymlink_hdr {
1437 	__be32	sl_magic;
1438 	__be32	sl_offset;
1439 	__be32	sl_bytes;
1440 	__be32	sl_crc;
1441 	uuid_t	sl_uuid;
1442 	__be64	sl_owner;
1443 	__be64	sl_blkno;
1444 	__be64	sl_lsn;
1445 };
1446 
1447 #define XFS_SYMLINK_CRC_OFF	offsetof(struct xfs_dsymlink_hdr, sl_crc)
1448 
1449 #define XFS_SYMLINK_MAXLEN	1024
1450 /*
1451  * The maximum pathlen is 1024 bytes. Since the minimum file system
1452  * blocksize is 512 bytes, we can get a max of 3 extents back from
1453  * bmapi when crc headers are taken into account.
1454  */
1455 #define XFS_SYMLINK_MAPS 3
1456 
1457 #define XFS_SYMLINK_BUF_SPACE(mp, bufsize)	\
1458 	((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
1459 			sizeof(struct xfs_dsymlink_hdr) : 0))
1460 
1461 
1462 /*
1463  * Allocation Btree format definitions
1464  *
1465  * There are two on-disk btrees, one sorted by blockno and one sorted
1466  * by blockcount and blockno.  All blocks look the same to make the code
1467  * simpler; if we have time later, we'll make the optimizations.
1468  */
1469 #define	XFS_ABTB_MAGIC		0x41425442	/* 'ABTB' for bno tree */
1470 #define	XFS_ABTB_CRC_MAGIC	0x41423342	/* 'AB3B' */
1471 #define	XFS_ABTC_MAGIC		0x41425443	/* 'ABTC' for cnt tree */
1472 #define	XFS_ABTC_CRC_MAGIC	0x41423343	/* 'AB3C' */
1473 
1474 /*
1475  * Data record/key structure
1476  */
1477 typedef struct xfs_alloc_rec {
1478 	__be32		ar_startblock;	/* starting block number */
1479 	__be32		ar_blockcount;	/* count of free blocks */
1480 } xfs_alloc_rec_t, xfs_alloc_key_t;
1481 
1482 typedef struct xfs_alloc_rec_incore {
1483 	xfs_agblock_t	ar_startblock;	/* starting block number */
1484 	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
1485 } xfs_alloc_rec_incore_t;
1486 
1487 /* btree pointer type */
1488 typedef __be32 xfs_alloc_ptr_t;
1489 
1490 /*
1491  * Block numbers in the AG:
1492  * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1493  */
1494 #define	XFS_BNO_BLOCK(mp)	((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1495 #define	XFS_CNT_BLOCK(mp)	((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1496 
1497 
1498 /*
1499  * Inode Allocation Btree format definitions
1500  *
1501  * There is a btree for the inode map per allocation group.
1502  */
1503 #define	XFS_IBT_MAGIC		0x49414254	/* 'IABT' */
1504 #define	XFS_IBT_CRC_MAGIC	0x49414233	/* 'IAB3' */
1505 #define	XFS_FIBT_MAGIC		0x46494254	/* 'FIBT' */
1506 #define	XFS_FIBT_CRC_MAGIC	0x46494233	/* 'FIB3' */
1507 
1508 typedef uint64_t	xfs_inofree_t;
1509 #define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
1510 #define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
1511 #define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
1512 #define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
1513 
1514 #define XFS_INOBT_HOLEMASK_FULL		0	/* holemask for full chunk */
1515 #define XFS_INOBT_HOLEMASK_BITS		(NBBY * sizeof(uint16_t))
1516 #define XFS_INODES_PER_HOLEMASK_BIT	\
1517 	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
1518 
1519 static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1520 {
1521 	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1522 }
1523 
1524 /*
1525  * The on-disk inode record structure has two formats. The original "full"
1526  * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1527  * and replaces the 3 high-order freecount bytes wth the holemask and inode
1528  * count.
1529  *
1530  * The holemask of the sparse record format allows an inode chunk to have holes
1531  * that refer to blocks not owned by the inode record. This facilitates inode
1532  * allocation in the event of severe free space fragmentation.
1533  */
1534 typedef struct xfs_inobt_rec {
1535 	__be32		ir_startino;	/* starting inode number */
1536 	union {
1537 		struct {
1538 			__be32	ir_freecount;	/* count of free inodes */
1539 		} f;
1540 		struct {
1541 			__be16	ir_holemask;/* hole mask for sparse chunks */
1542 			__u8	ir_count;	/* total inode count */
1543 			__u8	ir_freecount;	/* count of free inodes */
1544 		} sp;
1545 	} ir_u;
1546 	__be64		ir_free;	/* free inode mask */
1547 } xfs_inobt_rec_t;
1548 
1549 typedef struct xfs_inobt_rec_incore {
1550 	xfs_agino_t	ir_startino;	/* starting inode number */
1551 	uint16_t	ir_holemask;	/* hole mask for sparse chunks */
1552 	uint8_t		ir_count;	/* total inode count */
1553 	uint8_t		ir_freecount;	/* count of free inodes (set bits) */
1554 	xfs_inofree_t	ir_free;	/* free inode mask */
1555 } xfs_inobt_rec_incore_t;
1556 
1557 static inline bool xfs_inobt_issparse(uint16_t holemask)
1558 {
1559 	/* non-zero holemask represents a sparse rec. */
1560 	return holemask;
1561 }
1562 
1563 /*
1564  * Key structure
1565  */
1566 typedef struct xfs_inobt_key {
1567 	__be32		ir_startino;	/* starting inode number */
1568 } xfs_inobt_key_t;
1569 
1570 /* btree pointer type */
1571 typedef __be32 xfs_inobt_ptr_t;
1572 
1573 /*
1574  * block numbers in the AG.
1575  */
1576 #define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1577 #define	XFS_FIBT_BLOCK(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1578 
1579 /*
1580  * Reverse mapping btree format definitions
1581  *
1582  * There is a btree for the reverse map per allocation group
1583  */
1584 #define	XFS_RMAP_CRC_MAGIC	0x524d4233	/* 'RMB3' */
1585 
1586 /*
1587  * Ownership info for an extent.  This is used to create reverse-mapping
1588  * entries.
1589  */
1590 #define XFS_OWNER_INFO_ATTR_FORK	(1 << 0)
1591 #define XFS_OWNER_INFO_BMBT_BLOCK	(1 << 1)
1592 struct xfs_owner_info {
1593 	uint64_t		oi_owner;
1594 	xfs_fileoff_t		oi_offset;
1595 	unsigned int		oi_flags;
1596 };
1597 
1598 /*
1599  * Special owner types.
1600  *
1601  * Seeing as we only support up to 8EB, we have the upper bit of the owner field
1602  * to tell us we have a special owner value. We use these for static metadata
1603  * allocated at mkfs/growfs time, as well as for freespace management metadata.
1604  */
1605 #define XFS_RMAP_OWN_NULL	(-1ULL)	/* No owner, for growfs */
1606 #define XFS_RMAP_OWN_UNKNOWN	(-2ULL)	/* Unknown owner, for EFI recovery */
1607 #define XFS_RMAP_OWN_FS		(-3ULL)	/* static fs metadata */
1608 #define XFS_RMAP_OWN_LOG	(-4ULL)	/* static fs metadata */
1609 #define XFS_RMAP_OWN_AG		(-5ULL)	/* AG freespace btree blocks */
1610 #define XFS_RMAP_OWN_INOBT	(-6ULL)	/* Inode btree blocks */
1611 #define XFS_RMAP_OWN_INODES	(-7ULL)	/* Inode chunk */
1612 #define XFS_RMAP_OWN_REFC	(-8ULL) /* refcount tree */
1613 #define XFS_RMAP_OWN_COW	(-9ULL) /* cow allocations */
1614 #define XFS_RMAP_OWN_MIN	(-10ULL) /* guard */
1615 
1616 #define XFS_RMAP_NON_INODE_OWNER(owner)	(!!((owner) & (1ULL << 63)))
1617 
1618 /*
1619  * Data record structure
1620  */
1621 struct xfs_rmap_rec {
1622 	__be32		rm_startblock;	/* extent start block */
1623 	__be32		rm_blockcount;	/* extent length */
1624 	__be64		rm_owner;	/* extent owner */
1625 	__be64		rm_offset;	/* offset within the owner */
1626 };
1627 
1628 /*
1629  * rmap btree record
1630  *  rm_offset:63 is the attribute fork flag
1631  *  rm_offset:62 is the bmbt block flag
1632  *  rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt)
1633  *  rm_offset:54-60 aren't used and should be zero
1634  *  rm_offset:0-53 is the block offset within the inode
1635  */
1636 #define XFS_RMAP_OFF_ATTR_FORK	((uint64_t)1ULL << 63)
1637 #define XFS_RMAP_OFF_BMBT_BLOCK	((uint64_t)1ULL << 62)
1638 #define XFS_RMAP_OFF_UNWRITTEN	((uint64_t)1ULL << 61)
1639 
1640 #define XFS_RMAP_LEN_MAX	((uint32_t)~0U)
1641 #define XFS_RMAP_OFF_FLAGS	(XFS_RMAP_OFF_ATTR_FORK | \
1642 				 XFS_RMAP_OFF_BMBT_BLOCK | \
1643 				 XFS_RMAP_OFF_UNWRITTEN)
1644 #define XFS_RMAP_OFF_MASK	((uint64_t)0x3FFFFFFFFFFFFFULL)
1645 
1646 #define XFS_RMAP_OFF(off)		((off) & XFS_RMAP_OFF_MASK)
1647 
1648 #define XFS_RMAP_IS_BMBT_BLOCK(off)	(!!((off) & XFS_RMAP_OFF_BMBT_BLOCK))
1649 #define XFS_RMAP_IS_ATTR_FORK(off)	(!!((off) & XFS_RMAP_OFF_ATTR_FORK))
1650 #define XFS_RMAP_IS_UNWRITTEN(len)	(!!((off) & XFS_RMAP_OFF_UNWRITTEN))
1651 
1652 #define RMAPBT_STARTBLOCK_BITLEN	32
1653 #define RMAPBT_BLOCKCOUNT_BITLEN	32
1654 #define RMAPBT_OWNER_BITLEN		64
1655 #define RMAPBT_ATTRFLAG_BITLEN		1
1656 #define RMAPBT_BMBTFLAG_BITLEN		1
1657 #define RMAPBT_EXNTFLAG_BITLEN		1
1658 #define RMAPBT_UNUSED_OFFSET_BITLEN	7
1659 #define RMAPBT_OFFSET_BITLEN		54
1660 
1661 #define XFS_RMAP_ATTR_FORK		(1 << 0)
1662 #define XFS_RMAP_BMBT_BLOCK		(1 << 1)
1663 #define XFS_RMAP_UNWRITTEN		(1 << 2)
1664 #define XFS_RMAP_KEY_FLAGS		(XFS_RMAP_ATTR_FORK | \
1665 					 XFS_RMAP_BMBT_BLOCK)
1666 #define XFS_RMAP_REC_FLAGS		(XFS_RMAP_UNWRITTEN)
1667 struct xfs_rmap_irec {
1668 	xfs_agblock_t	rm_startblock;	/* extent start block */
1669 	xfs_extlen_t	rm_blockcount;	/* extent length */
1670 	uint64_t	rm_owner;	/* extent owner */
1671 	uint64_t	rm_offset;	/* offset within the owner */
1672 	unsigned int	rm_flags;	/* state flags */
1673 };
1674 
1675 /*
1676  * Key structure
1677  *
1678  * We don't use the length for lookups
1679  */
1680 struct xfs_rmap_key {
1681 	__be32		rm_startblock;	/* extent start block */
1682 	__be64		rm_owner;	/* extent owner */
1683 	__be64		rm_offset;	/* offset within the owner */
1684 } __attribute__((packed));
1685 
1686 /* btree pointer type */
1687 typedef __be32 xfs_rmap_ptr_t;
1688 
1689 #define	XFS_RMAP_BLOCK(mp) \
1690 	(xfs_sb_version_hasfinobt(&((mp)->m_sb)) ? \
1691 	 XFS_FIBT_BLOCK(mp) + 1 : \
1692 	 XFS_IBT_BLOCK(mp) + 1)
1693 
1694 /*
1695  * Reference Count Btree format definitions
1696  *
1697  */
1698 #define	XFS_REFC_CRC_MAGIC	0x52334643	/* 'R3FC' */
1699 
1700 unsigned int xfs_refc_block(struct xfs_mount *mp);
1701 
1702 /*
1703  * Data record/key structure
1704  *
1705  * Each record associates a range of physical blocks (starting at
1706  * rc_startblock and ending rc_blockcount blocks later) with a reference
1707  * count (rc_refcount).  Extents that are being used to stage a copy on
1708  * write (CoW) operation are recorded in the refcount btree with a
1709  * refcount of 1.  All other records must have a refcount > 1 and must
1710  * track an extent mapped only by file data forks.
1711  *
1712  * Extents with a single owner (attributes, metadata, non-shared file
1713  * data) are not tracked here.  Free space is also not tracked here.
1714  * This is consistent with pre-reflink XFS.
1715  */
1716 
1717 /*
1718  * Extents that are being used to stage a copy on write are stored
1719  * in the refcount btree with a refcount of 1 and the upper bit set
1720  * on the startblock.  This speeds up mount time deletion of stale
1721  * staging extents because they're all at the right side of the tree.
1722  */
1723 #define XFS_REFC_COW_START		((xfs_agblock_t)(1U << 31))
1724 #define REFCNTBT_COWFLAG_BITLEN		1
1725 #define REFCNTBT_AGBLOCK_BITLEN		31
1726 
1727 struct xfs_refcount_rec {
1728 	__be32		rc_startblock;	/* starting block number */
1729 	__be32		rc_blockcount;	/* count of blocks */
1730 	__be32		rc_refcount;	/* number of inodes linked here */
1731 };
1732 
1733 struct xfs_refcount_key {
1734 	__be32		rc_startblock;	/* starting block number */
1735 };
1736 
1737 struct xfs_refcount_irec {
1738 	xfs_agblock_t	rc_startblock;	/* starting block number */
1739 	xfs_extlen_t	rc_blockcount;	/* count of free blocks */
1740 	xfs_nlink_t	rc_refcount;	/* number of inodes linked here */
1741 };
1742 
1743 #define MAXREFCOUNT	((xfs_nlink_t)~0U)
1744 #define MAXREFCEXTLEN	((xfs_extlen_t)~0U)
1745 
1746 /* btree pointer type */
1747 typedef __be32 xfs_refcount_ptr_t;
1748 
1749 
1750 /*
1751  * BMAP Btree format definitions
1752  *
1753  * This includes both the root block definition that sits inside an inode fork
1754  * and the record/pointer formats for the leaf/node in the blocks.
1755  */
1756 #define XFS_BMAP_MAGIC		0x424d4150	/* 'BMAP' */
1757 #define XFS_BMAP_CRC_MAGIC	0x424d4133	/* 'BMA3' */
1758 
1759 /*
1760  * Bmap root header, on-disk form only.
1761  */
1762 typedef struct xfs_bmdr_block {
1763 	__be16		bb_level;	/* 0 is a leaf */
1764 	__be16		bb_numrecs;	/* current # of data records */
1765 } xfs_bmdr_block_t;
1766 
1767 /*
1768  * Bmap btree record and extent descriptor.
1769  *  l0:63 is an extent flag (value 1 indicates non-normal).
1770  *  l0:9-62 are startoff.
1771  *  l0:0-8 and l1:21-63 are startblock.
1772  *  l1:0-20 are blockcount.
1773  */
1774 #define BMBT_EXNTFLAG_BITLEN	1
1775 #define BMBT_STARTOFF_BITLEN	54
1776 #define BMBT_STARTBLOCK_BITLEN	52
1777 #define BMBT_BLOCKCOUNT_BITLEN	21
1778 
1779 #define BMBT_STARTOFF_MASK	((1ULL << BMBT_STARTOFF_BITLEN) - 1)
1780 #define BMBT_BLOCKCOUNT_MASK	((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
1781 
1782 /*
1783  * bmbt records have a file offset (block) field that is 54 bits wide, so this
1784  * is the largest xfs_fileoff_t that we ever expect to see.
1785  */
1786 #define XFS_MAX_FILEOFF		(BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
1787 
1788 typedef struct xfs_bmbt_rec {
1789 	__be64			l0, l1;
1790 } xfs_bmbt_rec_t;
1791 
1792 typedef uint64_t	xfs_bmbt_rec_base_t;	/* use this for casts */
1793 typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1794 
1795 /*
1796  * Values and macros for delayed-allocation startblock fields.
1797  */
1798 #define STARTBLOCKVALBITS	17
1799 #define STARTBLOCKMASKBITS	(15 + 20)
1800 #define STARTBLOCKMASK		\
1801 	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1802 
1803 static inline int isnullstartblock(xfs_fsblock_t x)
1804 {
1805 	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1806 }
1807 
1808 static inline xfs_fsblock_t nullstartblock(int k)
1809 {
1810 	ASSERT(k < (1 << STARTBLOCKVALBITS));
1811 	return STARTBLOCKMASK | (k);
1812 }
1813 
1814 static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1815 {
1816 	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1817 }
1818 
1819 /*
1820  * Key structure for non-leaf levels of the tree.
1821  */
1822 typedef struct xfs_bmbt_key {
1823 	__be64		br_startoff;	/* starting file offset */
1824 } xfs_bmbt_key_t, xfs_bmdr_key_t;
1825 
1826 /* btree pointer type */
1827 typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1828 
1829 
1830 /*
1831  * Generic Btree block format definitions
1832  *
1833  * This is a combination of the actual format used on disk for short and long
1834  * format btrees.  The first three fields are shared by both format, but the
1835  * pointers are different and should be used with care.
1836  *
1837  * To get the size of the actual short or long form headers please use the size
1838  * macros below.  Never use sizeof(xfs_btree_block).
1839  *
1840  * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1841  * with the crc feature bit, and all accesses to them must be conditional on
1842  * that flag.
1843  */
1844 /* short form block header */
1845 struct xfs_btree_block_shdr {
1846 	__be32		bb_leftsib;
1847 	__be32		bb_rightsib;
1848 
1849 	__be64		bb_blkno;
1850 	__be64		bb_lsn;
1851 	uuid_t		bb_uuid;
1852 	__be32		bb_owner;
1853 	__le32		bb_crc;
1854 };
1855 
1856 /* long form block header */
1857 struct xfs_btree_block_lhdr {
1858 	__be64		bb_leftsib;
1859 	__be64		bb_rightsib;
1860 
1861 	__be64		bb_blkno;
1862 	__be64		bb_lsn;
1863 	uuid_t		bb_uuid;
1864 	__be64		bb_owner;
1865 	__le32		bb_crc;
1866 	__be32		bb_pad; /* padding for alignment */
1867 };
1868 
1869 struct xfs_btree_block {
1870 	__be32		bb_magic;	/* magic number for block type */
1871 	__be16		bb_level;	/* 0 is a leaf */
1872 	__be16		bb_numrecs;	/* current # of data records */
1873 	union {
1874 		struct xfs_btree_block_shdr s;
1875 		struct xfs_btree_block_lhdr l;
1876 	} bb_u;				/* rest */
1877 };
1878 
1879 /* size of a short form block */
1880 #define XFS_BTREE_SBLOCK_LEN \
1881 	(offsetof(struct xfs_btree_block, bb_u) + \
1882 	 offsetof(struct xfs_btree_block_shdr, bb_blkno))
1883 /* size of a long form block */
1884 #define XFS_BTREE_LBLOCK_LEN \
1885 	(offsetof(struct xfs_btree_block, bb_u) + \
1886 	 offsetof(struct xfs_btree_block_lhdr, bb_blkno))
1887 
1888 /* sizes of CRC enabled btree blocks */
1889 #define XFS_BTREE_SBLOCK_CRC_LEN \
1890 	(offsetof(struct xfs_btree_block, bb_u) + \
1891 	 sizeof(struct xfs_btree_block_shdr))
1892 #define XFS_BTREE_LBLOCK_CRC_LEN \
1893 	(offsetof(struct xfs_btree_block, bb_u) + \
1894 	 sizeof(struct xfs_btree_block_lhdr))
1895 
1896 #define XFS_BTREE_SBLOCK_CRC_OFF \
1897 	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1898 #define XFS_BTREE_LBLOCK_CRC_OFF \
1899 	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1900 
1901 /*
1902  * On-disk XFS access control list structure.
1903  */
1904 struct xfs_acl_entry {
1905 	__be32	ae_tag;
1906 	__be32	ae_id;
1907 	__be16	ae_perm;
1908 	__be16	ae_pad;		/* fill the implicit hole in the structure */
1909 };
1910 
1911 struct xfs_acl {
1912 	__be32			acl_cnt;
1913 	struct xfs_acl_entry	acl_entry[];
1914 };
1915 
1916 /*
1917  * The number of ACL entries allowed is defined by the on-disk format.
1918  * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
1919  * limited only by the maximum size of the xattr that stores the information.
1920  */
1921 #define XFS_ACL_MAX_ENTRIES(mp)	\
1922 	(xfs_sb_version_hascrc(&mp->m_sb) \
1923 		?  (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
1924 						sizeof(struct xfs_acl_entry) \
1925 		: 25)
1926 
1927 #define XFS_ACL_SIZE(cnt) \
1928 	(sizeof(struct xfs_acl) + \
1929 		sizeof(struct xfs_acl_entry) * cnt)
1930 
1931 #define XFS_ACL_MAX_SIZE(mp) \
1932 	XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
1933 
1934 
1935 /* On-disk XFS extended attribute names */
1936 #define SGI_ACL_FILE		"SGI_ACL_FILE"
1937 #define SGI_ACL_DEFAULT		"SGI_ACL_DEFAULT"
1938 #define SGI_ACL_FILE_SIZE	(sizeof(SGI_ACL_FILE)-1)
1939 #define SGI_ACL_DEFAULT_SIZE	(sizeof(SGI_ACL_DEFAULT)-1)
1940 
1941 #endif /* __XFS_FORMAT_H__ */
1942