xref: /openbmc/linux/fs/xfs/libxfs/xfs_format.h (revision 3b27d139)
1 /*
2  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #ifndef __XFS_FORMAT_H__
19 #define __XFS_FORMAT_H__
20 
21 /*
22  * XFS On Disk Format Definitions
23  *
24  * This header file defines all the on-disk format definitions for
25  * general XFS objects. Directory and attribute related objects are defined in
26  * xfs_da_format.h, which log and log item formats are defined in
27  * xfs_log_format.h. Everything else goes here.
28  */
29 
30 struct xfs_mount;
31 struct xfs_trans;
32 struct xfs_inode;
33 struct xfs_buf;
34 struct xfs_ifork;
35 
36 /*
37  * Super block
38  * Fits into a sector-sized buffer at address 0 of each allocation group.
39  * Only the first of these is ever updated except during growfs.
40  */
41 #define	XFS_SB_MAGIC		0x58465342	/* 'XFSB' */
42 #define	XFS_SB_VERSION_1	1		/* 5.3, 6.0.1, 6.1 */
43 #define	XFS_SB_VERSION_2	2		/* 6.2 - attributes */
44 #define	XFS_SB_VERSION_3	3		/* 6.2 - new inode version */
45 #define	XFS_SB_VERSION_4	4		/* 6.2+ - bitmask version */
46 #define	XFS_SB_VERSION_5	5		/* CRC enabled filesystem */
47 #define	XFS_SB_VERSION_NUMBITS		0x000f
48 #define	XFS_SB_VERSION_ALLFBITS		0xfff0
49 #define	XFS_SB_VERSION_ATTRBIT		0x0010
50 #define	XFS_SB_VERSION_NLINKBIT		0x0020
51 #define	XFS_SB_VERSION_QUOTABIT		0x0040
52 #define	XFS_SB_VERSION_ALIGNBIT		0x0080
53 #define	XFS_SB_VERSION_DALIGNBIT	0x0100
54 #define	XFS_SB_VERSION_SHAREDBIT	0x0200
55 #define XFS_SB_VERSION_LOGV2BIT		0x0400
56 #define XFS_SB_VERSION_SECTORBIT	0x0800
57 #define	XFS_SB_VERSION_EXTFLGBIT	0x1000
58 #define	XFS_SB_VERSION_DIRV2BIT		0x2000
59 #define	XFS_SB_VERSION_BORGBIT		0x4000	/* ASCII only case-insens. */
60 #define	XFS_SB_VERSION_MOREBITSBIT	0x8000
61 
62 /*
63  * Supported feature bit list is just all bits in the versionnum field because
64  * we've used them all up and understand them all. Except, of course, for the
65  * shared superblock bit, which nobody knows what it does and so is unsupported.
66  */
67 #define	XFS_SB_VERSION_OKBITS		\
68 	((XFS_SB_VERSION_NUMBITS | XFS_SB_VERSION_ALLFBITS) & \
69 		~XFS_SB_VERSION_SHAREDBIT)
70 
71 /*
72  * There are two words to hold XFS "feature" bits: the original
73  * word, sb_versionnum, and sb_features2.  Whenever a bit is set in
74  * sb_features2, the feature bit XFS_SB_VERSION_MOREBITSBIT must be set.
75  *
76  * These defines represent bits in sb_features2.
77  */
78 #define XFS_SB_VERSION2_RESERVED1BIT	0x00000001
79 #define XFS_SB_VERSION2_LAZYSBCOUNTBIT	0x00000002	/* Superblk counters */
80 #define XFS_SB_VERSION2_RESERVED4BIT	0x00000004
81 #define XFS_SB_VERSION2_ATTR2BIT	0x00000008	/* Inline attr rework */
82 #define XFS_SB_VERSION2_PARENTBIT	0x00000010	/* parent pointers */
83 #define XFS_SB_VERSION2_PROJID32BIT	0x00000080	/* 32 bit project id */
84 #define XFS_SB_VERSION2_CRCBIT		0x00000100	/* metadata CRCs */
85 #define XFS_SB_VERSION2_FTYPE		0x00000200	/* inode type in dir */
86 
87 #define	XFS_SB_VERSION2_OKBITS		\
88 	(XFS_SB_VERSION2_LAZYSBCOUNTBIT	| \
89 	 XFS_SB_VERSION2_ATTR2BIT	| \
90 	 XFS_SB_VERSION2_PROJID32BIT	| \
91 	 XFS_SB_VERSION2_FTYPE)
92 
93 /*
94  * Superblock - in core version.  Must match the ondisk version below.
95  * Must be padded to 64 bit alignment.
96  */
97 typedef struct xfs_sb {
98 	__uint32_t	sb_magicnum;	/* magic number == XFS_SB_MAGIC */
99 	__uint32_t	sb_blocksize;	/* logical block size, bytes */
100 	xfs_rfsblock_t	sb_dblocks;	/* number of data blocks */
101 	xfs_rfsblock_t	sb_rblocks;	/* number of realtime blocks */
102 	xfs_rtblock_t	sb_rextents;	/* number of realtime extents */
103 	uuid_t		sb_uuid;	/* file system unique id */
104 	xfs_fsblock_t	sb_logstart;	/* starting block of log if internal */
105 	xfs_ino_t	sb_rootino;	/* root inode number */
106 	xfs_ino_t	sb_rbmino;	/* bitmap inode for realtime extents */
107 	xfs_ino_t	sb_rsumino;	/* summary inode for rt bitmap */
108 	xfs_agblock_t	sb_rextsize;	/* realtime extent size, blocks */
109 	xfs_agblock_t	sb_agblocks;	/* size of an allocation group */
110 	xfs_agnumber_t	sb_agcount;	/* number of allocation groups */
111 	xfs_extlen_t	sb_rbmblocks;	/* number of rt bitmap blocks */
112 	xfs_extlen_t	sb_logblocks;	/* number of log blocks */
113 	__uint16_t	sb_versionnum;	/* header version == XFS_SB_VERSION */
114 	__uint16_t	sb_sectsize;	/* volume sector size, bytes */
115 	__uint16_t	sb_inodesize;	/* inode size, bytes */
116 	__uint16_t	sb_inopblock;	/* inodes per block */
117 	char		sb_fname[12];	/* file system name */
118 	__uint8_t	sb_blocklog;	/* log2 of sb_blocksize */
119 	__uint8_t	sb_sectlog;	/* log2 of sb_sectsize */
120 	__uint8_t	sb_inodelog;	/* log2 of sb_inodesize */
121 	__uint8_t	sb_inopblog;	/* log2 of sb_inopblock */
122 	__uint8_t	sb_agblklog;	/* log2 of sb_agblocks (rounded up) */
123 	__uint8_t	sb_rextslog;	/* log2 of sb_rextents */
124 	__uint8_t	sb_inprogress;	/* mkfs is in progress, don't mount */
125 	__uint8_t	sb_imax_pct;	/* max % of fs for inode space */
126 					/* statistics */
127 	/*
128 	 * These fields must remain contiguous.  If you really
129 	 * want to change their layout, make sure you fix the
130 	 * code in xfs_trans_apply_sb_deltas().
131 	 */
132 	__uint64_t	sb_icount;	/* allocated inodes */
133 	__uint64_t	sb_ifree;	/* free inodes */
134 	__uint64_t	sb_fdblocks;	/* free data blocks */
135 	__uint64_t	sb_frextents;	/* free realtime extents */
136 	/*
137 	 * End contiguous fields.
138 	 */
139 	xfs_ino_t	sb_uquotino;	/* user quota inode */
140 	xfs_ino_t	sb_gquotino;	/* group quota inode */
141 	__uint16_t	sb_qflags;	/* quota flags */
142 	__uint8_t	sb_flags;	/* misc. flags */
143 	__uint8_t	sb_shared_vn;	/* shared version number */
144 	xfs_extlen_t	sb_inoalignmt;	/* inode chunk alignment, fsblocks */
145 	__uint32_t	sb_unit;	/* stripe or raid unit */
146 	__uint32_t	sb_width;	/* stripe or raid width */
147 	__uint8_t	sb_dirblklog;	/* log2 of dir block size (fsbs) */
148 	__uint8_t	sb_logsectlog;	/* log2 of the log sector size */
149 	__uint16_t	sb_logsectsize;	/* sector size for the log, bytes */
150 	__uint32_t	sb_logsunit;	/* stripe unit size for the log */
151 	__uint32_t	sb_features2;	/* additional feature bits */
152 
153 	/*
154 	 * bad features2 field as a result of failing to pad the sb structure to
155 	 * 64 bits. Some machines will be using this field for features2 bits.
156 	 * Easiest just to mark it bad and not use it for anything else.
157 	 *
158 	 * This is not kept up to date in memory; it is always overwritten by
159 	 * the value in sb_features2 when formatting the incore superblock to
160 	 * the disk buffer.
161 	 */
162 	__uint32_t	sb_bad_features2;
163 
164 	/* version 5 superblock fields start here */
165 
166 	/* feature masks */
167 	__uint32_t	sb_features_compat;
168 	__uint32_t	sb_features_ro_compat;
169 	__uint32_t	sb_features_incompat;
170 	__uint32_t	sb_features_log_incompat;
171 
172 	__uint32_t	sb_crc;		/* superblock crc */
173 	xfs_extlen_t	sb_spino_align;	/* sparse inode chunk alignment */
174 
175 	xfs_ino_t	sb_pquotino;	/* project quota inode */
176 	xfs_lsn_t	sb_lsn;		/* last write sequence */
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;	/* 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[12];	/* 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 
264 	/* must be padded to 64 bit alignment */
265 } xfs_dsb_t;
266 
267 
268 /*
269  * Misc. Flags - warning - these will be cleared by xfs_repair unless
270  * a feature bit is set when the flag is used.
271  */
272 #define XFS_SBF_NOFLAGS		0x00	/* no flags set */
273 #define XFS_SBF_READONLY	0x01	/* only read-only mounts allowed */
274 
275 /*
276  * define max. shared version we can interoperate with
277  */
278 #define XFS_SB_MAX_SHARED_VN	0
279 
280 #define	XFS_SB_VERSION_NUM(sbp)	((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
281 
282 /*
283  * The first XFS version we support is a v4 superblock with V2 directories.
284  */
285 static inline bool xfs_sb_good_v4_features(struct xfs_sb *sbp)
286 {
287 	if (!(sbp->sb_versionnum & XFS_SB_VERSION_DIRV2BIT))
288 		return false;
289 
290 	/* check for unknown features in the fs */
291 	if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) ||
292 	    ((sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT) &&
293 	     (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS)))
294 		return false;
295 
296 	return true;
297 }
298 
299 static inline bool xfs_sb_good_version(struct xfs_sb *sbp)
300 {
301 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5)
302 		return true;
303 	if (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_4)
304 		return xfs_sb_good_v4_features(sbp);
305 	return false;
306 }
307 
308 /*
309  * Detect a mismatched features2 field.  Older kernels read/wrote
310  * this into the wrong slot, so to be safe we keep them in sync.
311  */
312 static inline bool xfs_sb_has_mismatched_features2(struct xfs_sb *sbp)
313 {
314 	return sbp->sb_bad_features2 != sbp->sb_features2;
315 }
316 
317 static inline bool xfs_sb_version_hasattr(struct xfs_sb *sbp)
318 {
319 	return (sbp->sb_versionnum & XFS_SB_VERSION_ATTRBIT);
320 }
321 
322 static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
323 {
324 	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
325 }
326 
327 static inline bool xfs_sb_version_hasquota(struct xfs_sb *sbp)
328 {
329 	return (sbp->sb_versionnum & XFS_SB_VERSION_QUOTABIT);
330 }
331 
332 static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
333 {
334 	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
335 }
336 
337 static inline bool xfs_sb_version_hasalign(struct xfs_sb *sbp)
338 {
339 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
340 		(sbp->sb_versionnum & XFS_SB_VERSION_ALIGNBIT));
341 }
342 
343 static inline bool xfs_sb_version_hasdalign(struct xfs_sb *sbp)
344 {
345 	return (sbp->sb_versionnum & XFS_SB_VERSION_DALIGNBIT);
346 }
347 
348 static inline bool xfs_sb_version_haslogv2(struct xfs_sb *sbp)
349 {
350 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
351 	       (sbp->sb_versionnum & XFS_SB_VERSION_LOGV2BIT);
352 }
353 
354 static inline bool xfs_sb_version_hasextflgbit(struct xfs_sb *sbp)
355 {
356 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
357 	       (sbp->sb_versionnum & XFS_SB_VERSION_EXTFLGBIT);
358 }
359 
360 static inline bool xfs_sb_version_hassector(struct xfs_sb *sbp)
361 {
362 	return (sbp->sb_versionnum & XFS_SB_VERSION_SECTORBIT);
363 }
364 
365 static inline bool xfs_sb_version_hasasciici(struct xfs_sb *sbp)
366 {
367 	return (sbp->sb_versionnum & XFS_SB_VERSION_BORGBIT);
368 }
369 
370 static inline bool xfs_sb_version_hasmorebits(struct xfs_sb *sbp)
371 {
372 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 ||
373 	       (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
374 }
375 
376 /*
377  * sb_features2 bit version macros.
378  */
379 static inline bool xfs_sb_version_haslazysbcount(struct xfs_sb *sbp)
380 {
381 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
382 	       (xfs_sb_version_hasmorebits(sbp) &&
383 		(sbp->sb_features2 & XFS_SB_VERSION2_LAZYSBCOUNTBIT));
384 }
385 
386 static inline bool xfs_sb_version_hasattr2(struct xfs_sb *sbp)
387 {
388 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
389 	       (xfs_sb_version_hasmorebits(sbp) &&
390 		(sbp->sb_features2 & XFS_SB_VERSION2_ATTR2BIT));
391 }
392 
393 static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
394 {
395 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
396 	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
397 }
398 
399 static inline void xfs_sb_version_removeattr2(struct xfs_sb *sbp)
400 {
401 	sbp->sb_features2 &= ~XFS_SB_VERSION2_ATTR2BIT;
402 	if (!sbp->sb_features2)
403 		sbp->sb_versionnum &= ~XFS_SB_VERSION_MOREBITSBIT;
404 }
405 
406 static inline bool xfs_sb_version_hasprojid32bit(struct xfs_sb *sbp)
407 {
408 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) ||
409 	       (xfs_sb_version_hasmorebits(sbp) &&
410 		(sbp->sb_features2 & XFS_SB_VERSION2_PROJID32BIT));
411 }
412 
413 static inline void xfs_sb_version_addprojid32bit(struct xfs_sb *sbp)
414 {
415 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
416 	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
417 }
418 
419 /*
420  * Extended v5 superblock feature masks. These are to be used for new v5
421  * superblock features only.
422  *
423  * Compat features are new features that old kernels will not notice or affect
424  * and so can mount read-write without issues.
425  *
426  * RO-Compat (read only) are features that old kernels can read but will break
427  * if they write. Hence only read-only mounts of such filesystems are allowed on
428  * kernels that don't support the feature bit.
429  *
430  * InCompat features are features which old kernels will not understand and so
431  * must not mount.
432  *
433  * Log-InCompat features are for changes to log formats or new transactions that
434  * can't be replayed on older kernels. The fields are set when the filesystem is
435  * mounted, and a clean unmount clears the fields.
436  */
437 #define XFS_SB_FEAT_COMPAT_ALL 0
438 #define XFS_SB_FEAT_COMPAT_UNKNOWN	~XFS_SB_FEAT_COMPAT_ALL
439 static inline bool
440 xfs_sb_has_compat_feature(
441 	struct xfs_sb	*sbp,
442 	__uint32_t	feature)
443 {
444 	return (sbp->sb_features_compat & feature) != 0;
445 }
446 
447 #define XFS_SB_FEAT_RO_COMPAT_FINOBT   (1 << 0)		/* free inode btree */
448 #define XFS_SB_FEAT_RO_COMPAT_ALL \
449 		(XFS_SB_FEAT_RO_COMPAT_FINOBT)
450 #define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
451 static inline bool
452 xfs_sb_has_ro_compat_feature(
453 	struct xfs_sb	*sbp,
454 	__uint32_t	feature)
455 {
456 	return (sbp->sb_features_ro_compat & feature) != 0;
457 }
458 
459 #define XFS_SB_FEAT_INCOMPAT_FTYPE	(1 << 0)	/* filetype in dirent */
460 #define XFS_SB_FEAT_INCOMPAT_SPINODES	(1 << 1)	/* sparse inode chunks */
461 #define XFS_SB_FEAT_INCOMPAT_ALL \
462 		(XFS_SB_FEAT_INCOMPAT_FTYPE|	\
463 		 XFS_SB_FEAT_INCOMPAT_SPINODES)
464 
465 #define XFS_SB_FEAT_INCOMPAT_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_ALL
466 static inline bool
467 xfs_sb_has_incompat_feature(
468 	struct xfs_sb	*sbp,
469 	__uint32_t	feature)
470 {
471 	return (sbp->sb_features_incompat & feature) != 0;
472 }
473 
474 #define XFS_SB_FEAT_INCOMPAT_LOG_ALL 0
475 #define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_LOG_ALL
476 static inline bool
477 xfs_sb_has_incompat_log_feature(
478 	struct xfs_sb	*sbp,
479 	__uint32_t	feature)
480 {
481 	return (sbp->sb_features_log_incompat & feature) != 0;
482 }
483 
484 /*
485  * V5 superblock specific feature checks
486  */
487 static inline int xfs_sb_version_hascrc(struct xfs_sb *sbp)
488 {
489 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
490 }
491 
492 static inline int xfs_sb_version_has_pquotino(struct xfs_sb *sbp)
493 {
494 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
495 }
496 
497 static inline int xfs_sb_version_hasftype(struct xfs_sb *sbp)
498 {
499 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
500 		xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_FTYPE)) ||
501 	       (xfs_sb_version_hasmorebits(sbp) &&
502 		 (sbp->sb_features2 & XFS_SB_VERSION2_FTYPE));
503 }
504 
505 static inline int xfs_sb_version_hasfinobt(xfs_sb_t *sbp)
506 {
507 	return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) &&
508 		(sbp->sb_features_ro_compat & XFS_SB_FEAT_RO_COMPAT_FINOBT);
509 }
510 
511 static inline bool xfs_sb_version_hassparseinodes(struct xfs_sb *sbp)
512 {
513 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5 &&
514 		xfs_sb_has_incompat_feature(sbp, XFS_SB_FEAT_INCOMPAT_SPINODES);
515 }
516 
517 /*
518  * end of superblock version macros
519  */
520 
521 static inline bool
522 xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
523 {
524 	return (ino == sbp->sb_uquotino ||
525 		ino == sbp->sb_gquotino ||
526 		ino == sbp->sb_pquotino);
527 }
528 
529 #define XFS_SB_DADDR		((xfs_daddr_t)0) /* daddr in filesystem/ag */
530 #define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
531 #define XFS_BUF_TO_SBP(bp)	((xfs_dsb_t *)((bp)->b_addr))
532 
533 #define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
534 #define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
535 			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
536 #define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
537 			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
538 
539 /*
540  * File system sector to basic block conversions.
541  */
542 #define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)
543 
544 /*
545  * File system block to basic block conversions.
546  */
547 #define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
548 #define	XFS_BB_TO_FSB(mp,bb)	\
549 	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
550 #define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)
551 
552 /*
553  * File system block to byte conversions.
554  */
555 #define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
556 #define XFS_B_TO_FSB(mp,b)	\
557 	((((__uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
558 #define XFS_B_TO_FSBT(mp,b)	(((__uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
559 #define XFS_B_FSB_OFFSET(mp,b)	((b) & (mp)->m_blockmask)
560 
561 /*
562  * Allocation group header
563  *
564  * This is divided into three structures, placed in sequential 512-byte
565  * buffers after a copy of the superblock (also in a 512-byte buffer).
566  */
567 #define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
568 #define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
569 #define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
570 #define	XFS_AGF_VERSION	1
571 #define	XFS_AGI_VERSION	1
572 
573 #define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
574 #define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
575 
576 /*
577  * Btree number 0 is bno, 1 is cnt.  This value gives the size of the
578  * arrays below.
579  */
580 #define	XFS_BTNUM_AGF	((int)XFS_BTNUM_CNTi + 1)
581 
582 /*
583  * The second word of agf_levels in the first a.g. overlaps the EFS
584  * superblock's magic number.  Since the magic numbers valid for EFS
585  * are > 64k, our value cannot be confused for an EFS superblock's.
586  */
587 
588 typedef struct xfs_agf {
589 	/*
590 	 * Common allocation group header information
591 	 */
592 	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
593 	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
594 	__be32		agf_seqno;	/* sequence # starting from 0 */
595 	__be32		agf_length;	/* size in blocks of a.g. */
596 	/*
597 	 * Freespace information
598 	 */
599 	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
600 	__be32		agf_spare0;	/* spare field */
601 	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
602 	__be32		agf_spare1;	/* spare field */
603 
604 	__be32		agf_flfirst;	/* first freelist block's index */
605 	__be32		agf_fllast;	/* last freelist block's index */
606 	__be32		agf_flcount;	/* count of blocks in freelist */
607 	__be32		agf_freeblks;	/* total free blocks */
608 
609 	__be32		agf_longest;	/* longest free space */
610 	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
611 	uuid_t		agf_uuid;	/* uuid of filesystem */
612 
613 	/*
614 	 * reserve some contiguous space for future logged fields before we add
615 	 * the unlogged fields. This makes the range logging via flags and
616 	 * structure offsets much simpler.
617 	 */
618 	__be64		agf_spare64[16];
619 
620 	/* unlogged fields, written during buffer writeback. */
621 	__be64		agf_lsn;	/* last write sequence */
622 	__be32		agf_crc;	/* crc of agf sector */
623 	__be32		agf_spare2;
624 
625 	/* structure must be padded to 64 bit alignment */
626 } xfs_agf_t;
627 
628 #define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
629 
630 #define	XFS_AGF_MAGICNUM	0x00000001
631 #define	XFS_AGF_VERSIONNUM	0x00000002
632 #define	XFS_AGF_SEQNO		0x00000004
633 #define	XFS_AGF_LENGTH		0x00000008
634 #define	XFS_AGF_ROOTS		0x00000010
635 #define	XFS_AGF_LEVELS		0x00000020
636 #define	XFS_AGF_FLFIRST		0x00000040
637 #define	XFS_AGF_FLLAST		0x00000080
638 #define	XFS_AGF_FLCOUNT		0x00000100
639 #define	XFS_AGF_FREEBLKS	0x00000200
640 #define	XFS_AGF_LONGEST		0x00000400
641 #define	XFS_AGF_BTREEBLKS	0x00000800
642 #define	XFS_AGF_UUID		0x00001000
643 #define	XFS_AGF_NUM_BITS	13
644 #define	XFS_AGF_ALL_BITS	((1 << XFS_AGF_NUM_BITS) - 1)
645 
646 #define XFS_AGF_FLAGS \
647 	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
648 	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
649 	{ XFS_AGF_SEQNO,	"SEQNO" }, \
650 	{ XFS_AGF_LENGTH,	"LENGTH" }, \
651 	{ XFS_AGF_ROOTS,	"ROOTS" }, \
652 	{ XFS_AGF_LEVELS,	"LEVELS" }, \
653 	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
654 	{ XFS_AGF_FLLAST,	"FLLAST" }, \
655 	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
656 	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
657 	{ XFS_AGF_LONGEST,	"LONGEST" }, \
658 	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
659 	{ XFS_AGF_UUID,		"UUID" }
660 
661 /* disk block (xfs_daddr_t) in the AG */
662 #define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
663 #define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
664 #define	XFS_BUF_TO_AGF(bp)	((xfs_agf_t *)((bp)->b_addr))
665 
666 /*
667  * Size of the unlinked inode hash table in the agi.
668  */
669 #define	XFS_AGI_UNLINKED_BUCKETS	64
670 
671 typedef struct xfs_agi {
672 	/*
673 	 * Common allocation group header information
674 	 */
675 	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
676 	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
677 	__be32		agi_seqno;	/* sequence # starting from 0 */
678 	__be32		agi_length;	/* size in blocks of a.g. */
679 	/*
680 	 * Inode information
681 	 * Inodes are mapped by interpreting the inode number, so no
682 	 * mapping data is needed here.
683 	 */
684 	__be32		agi_count;	/* count of allocated inodes */
685 	__be32		agi_root;	/* root of inode btree */
686 	__be32		agi_level;	/* levels in inode btree */
687 	__be32		agi_freecount;	/* number of free inodes */
688 
689 	__be32		agi_newino;	/* new inode just allocated */
690 	__be32		agi_dirino;	/* last directory inode chunk */
691 	/*
692 	 * Hash table of inodes which have been unlinked but are
693 	 * still being referenced.
694 	 */
695 	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
696 	/*
697 	 * This marks the end of logging region 1 and start of logging region 2.
698 	 */
699 	uuid_t		agi_uuid;	/* uuid of filesystem */
700 	__be32		agi_crc;	/* crc of agi sector */
701 	__be32		agi_pad32;
702 	__be64		agi_lsn;	/* last write sequence */
703 
704 	__be32		agi_free_root; /* root of the free inode btree */
705 	__be32		agi_free_level;/* levels in free inode btree */
706 
707 	/* structure must be padded to 64 bit alignment */
708 } xfs_agi_t;
709 
710 #define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
711 
712 #define	XFS_AGI_MAGICNUM	(1 << 0)
713 #define	XFS_AGI_VERSIONNUM	(1 << 1)
714 #define	XFS_AGI_SEQNO		(1 << 2)
715 #define	XFS_AGI_LENGTH		(1 << 3)
716 #define	XFS_AGI_COUNT		(1 << 4)
717 #define	XFS_AGI_ROOT		(1 << 5)
718 #define	XFS_AGI_LEVEL		(1 << 6)
719 #define	XFS_AGI_FREECOUNT	(1 << 7)
720 #define	XFS_AGI_NEWINO		(1 << 8)
721 #define	XFS_AGI_DIRINO		(1 << 9)
722 #define	XFS_AGI_UNLINKED	(1 << 10)
723 #define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
724 #define	XFS_AGI_ALL_BITS_R1	((1 << XFS_AGI_NUM_BITS_R1) - 1)
725 #define	XFS_AGI_FREE_ROOT	(1 << 11)
726 #define	XFS_AGI_FREE_LEVEL	(1 << 12)
727 #define	XFS_AGI_NUM_BITS_R2	13
728 
729 /* disk block (xfs_daddr_t) in the AG */
730 #define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
731 #define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
732 #define	XFS_BUF_TO_AGI(bp)	((xfs_agi_t *)((bp)->b_addr))
733 
734 /*
735  * The third a.g. block contains the a.g. freelist, an array
736  * of block pointers to blocks owned by the allocation btree code.
737  */
738 #define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
739 #define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
740 #define	XFS_BUF_TO_AGFL(bp)	((xfs_agfl_t *)((bp)->b_addr))
741 
742 #define XFS_BUF_TO_AGFL_BNO(mp, bp) \
743 	(xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
744 		&(XFS_BUF_TO_AGFL(bp)->agfl_bno[0]) : \
745 		(__be32 *)(bp)->b_addr)
746 
747 /*
748  * Size of the AGFL.  For CRC-enabled filesystes we steal a couple of
749  * slots in the beginning of the block for a proper header with the
750  * location information and CRC.
751  */
752 #define XFS_AGFL_SIZE(mp) \
753 	(((mp)->m_sb.sb_sectsize - \
754 	 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
755 		sizeof(struct xfs_agfl) : 0)) / \
756 	  sizeof(xfs_agblock_t))
757 
758 typedef struct xfs_agfl {
759 	__be32		agfl_magicnum;
760 	__be32		agfl_seqno;
761 	uuid_t		agfl_uuid;
762 	__be64		agfl_lsn;
763 	__be32		agfl_crc;
764 	__be32		agfl_bno[];	/* actually XFS_AGFL_SIZE(mp) */
765 } xfs_agfl_t;
766 
767 #define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
768 
769 #define XFS_AGB_TO_FSB(mp,agno,agbno)	\
770 	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
771 #define	XFS_FSB_TO_AGNO(mp,fsbno)	\
772 	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
773 #define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
774 	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
775 #define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
776 	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
777 		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
778 #define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
779 
780 /*
781  * For checking for bad ranges of xfs_daddr_t's, covering multiple
782  * allocation groups or a single xfs_daddr_t that's a superblock copy.
783  */
784 #define	XFS_AG_CHECK_DADDR(mp,d,len)	\
785 	((len) == 1 ? \
786 	    ASSERT((d) == XFS_SB_DADDR || \
787 		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
788 	    ASSERT(xfs_daddr_to_agno(mp, d) == \
789 		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
790 
791 typedef struct xfs_timestamp {
792 	__be32		t_sec;		/* timestamp seconds */
793 	__be32		t_nsec;		/* timestamp nanoseconds */
794 } xfs_timestamp_t;
795 
796 /*
797  * On-disk inode structure.
798  *
799  * This is just the header or "dinode core", the inode is expanded to fill a
800  * variable size the leftover area split into a data and an attribute fork.
801  * The format of the data and attribute fork depends on the format of the
802  * inode as indicated by di_format and di_aformat.  To access the data and
803  * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
804  * below.
805  *
806  * There is a very similar struct icdinode in xfs_inode which matches the
807  * layout of the first 96 bytes of this structure, but is kept in native
808  * format instead of big endian.
809  *
810  * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
811  * padding field for v3 inodes.
812  */
813 #define	XFS_DINODE_MAGIC		0x494e	/* 'IN' */
814 #define XFS_DINODE_GOOD_VERSION(v)	((v) >= 1 && (v) <= 3)
815 typedef struct xfs_dinode {
816 	__be16		di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
817 	__be16		di_mode;	/* mode and type of file */
818 	__u8		di_version;	/* inode version */
819 	__u8		di_format;	/* format of di_c data */
820 	__be16		di_onlink;	/* old number of links to file */
821 	__be32		di_uid;		/* owner's user id */
822 	__be32		di_gid;		/* owner's group id */
823 	__be32		di_nlink;	/* number of links to file */
824 	__be16		di_projid_lo;	/* lower part of owner's project id */
825 	__be16		di_projid_hi;	/* higher part owner's project id */
826 	__u8		di_pad[6];	/* unused, zeroed space */
827 	__be16		di_flushiter;	/* incremented on flush */
828 	xfs_timestamp_t	di_atime;	/* time last accessed */
829 	xfs_timestamp_t	di_mtime;	/* time last modified */
830 	xfs_timestamp_t	di_ctime;	/* time created/inode modified */
831 	__be64		di_size;	/* number of bytes in file */
832 	__be64		di_nblocks;	/* # of direct & btree blocks used */
833 	__be32		di_extsize;	/* basic/minimum extent size for file */
834 	__be32		di_nextents;	/* number of extents in data fork */
835 	__be16		di_anextents;	/* number of extents in attribute fork*/
836 	__u8		di_forkoff;	/* attr fork offs, <<3 for 64b align */
837 	__s8		di_aformat;	/* format of attr fork's data */
838 	__be32		di_dmevmask;	/* DMIG event mask */
839 	__be16		di_dmstate;	/* DMIG state info */
840 	__be16		di_flags;	/* random flags, XFS_DIFLAG_... */
841 	__be32		di_gen;		/* generation number */
842 
843 	/* di_next_unlinked is the only non-core field in the old dinode */
844 	__be32		di_next_unlinked;/* agi unlinked list ptr */
845 
846 	/* start of the extended dinode, writable fields */
847 	__le32		di_crc;		/* CRC of the inode */
848 	__be64		di_changecount;	/* number of attribute changes */
849 	__be64		di_lsn;		/* flush sequence */
850 	__be64		di_flags2;	/* more random flags */
851 	__u8		di_pad2[16];	/* more padding for future expansion */
852 
853 	/* fields only written to during inode creation */
854 	xfs_timestamp_t	di_crtime;	/* time created */
855 	__be64		di_ino;		/* inode number */
856 	uuid_t		di_uuid;	/* UUID of the filesystem */
857 
858 	/* structure must be padded to 64 bit alignment */
859 } xfs_dinode_t;
860 
861 #define XFS_DINODE_CRC_OFF	offsetof(struct xfs_dinode, di_crc)
862 
863 #define DI_MAX_FLUSH 0xffff
864 
865 /*
866  * Size of the core inode on disk.  Version 1 and 2 inodes have
867  * the same size, but version 3 has grown a few additional fields.
868  */
869 static inline uint xfs_dinode_size(int version)
870 {
871 	if (version == 3)
872 		return sizeof(struct xfs_dinode);
873 	return offsetof(struct xfs_dinode, di_crc);
874 }
875 
876 /*
877  * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
878  * Since the pathconf interface is signed, we use 2^31 - 1 instead.
879  * The old inode format had a 16 bit link count, so its maximum is USHRT_MAX.
880  */
881 #define	XFS_MAXLINK		((1U << 31) - 1U)
882 #define	XFS_MAXLINK_1		65535U
883 
884 /*
885  * Values for di_format
886  */
887 typedef enum xfs_dinode_fmt {
888 	XFS_DINODE_FMT_DEV,		/* xfs_dev_t */
889 	XFS_DINODE_FMT_LOCAL,		/* bulk data */
890 	XFS_DINODE_FMT_EXTENTS,		/* struct xfs_bmbt_rec */
891 	XFS_DINODE_FMT_BTREE,		/* struct xfs_bmdr_block */
892 	XFS_DINODE_FMT_UUID		/* uuid_t */
893 } xfs_dinode_fmt_t;
894 
895 /*
896  * Inode minimum and maximum sizes.
897  */
898 #define	XFS_DINODE_MIN_LOG	8
899 #define	XFS_DINODE_MAX_LOG	11
900 #define	XFS_DINODE_MIN_SIZE	(1 << XFS_DINODE_MIN_LOG)
901 #define	XFS_DINODE_MAX_SIZE	(1 << XFS_DINODE_MAX_LOG)
902 
903 /*
904  * Inode size for given fs.
905  */
906 #define XFS_LITINO(mp, version) \
907 	((int)(((mp)->m_sb.sb_inodesize) - xfs_dinode_size(version)))
908 
909 /*
910  * Inode data & attribute fork sizes, per inode.
911  */
912 #define XFS_DFORK_Q(dip)		((dip)->di_forkoff != 0)
913 #define XFS_DFORK_BOFF(dip)		((int)((dip)->di_forkoff << 3))
914 
915 #define XFS_DFORK_DSIZE(dip,mp) \
916 	(XFS_DFORK_Q(dip) ? \
917 		XFS_DFORK_BOFF(dip) : \
918 		XFS_LITINO(mp, (dip)->di_version))
919 #define XFS_DFORK_ASIZE(dip,mp) \
920 	(XFS_DFORK_Q(dip) ? \
921 		XFS_LITINO(mp, (dip)->di_version) - XFS_DFORK_BOFF(dip) : \
922 		0)
923 #define XFS_DFORK_SIZE(dip,mp,w) \
924 	((w) == XFS_DATA_FORK ? \
925 		XFS_DFORK_DSIZE(dip, mp) : \
926 		XFS_DFORK_ASIZE(dip, mp))
927 
928 /*
929  * Return pointers to the data or attribute forks.
930  */
931 #define XFS_DFORK_DPTR(dip) \
932 	((char *)dip + xfs_dinode_size(dip->di_version))
933 #define XFS_DFORK_APTR(dip)	\
934 	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
935 #define XFS_DFORK_PTR(dip,w)	\
936 	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
937 
938 #define XFS_DFORK_FORMAT(dip,w) \
939 	((w) == XFS_DATA_FORK ? \
940 		(dip)->di_format : \
941 		(dip)->di_aformat)
942 #define XFS_DFORK_NEXTENTS(dip,w) \
943 	((w) == XFS_DATA_FORK ? \
944 		be32_to_cpu((dip)->di_nextents) : \
945 		be16_to_cpu((dip)->di_anextents))
946 
947 /*
948  * For block and character special files the 32bit dev_t is stored at the
949  * beginning of the data fork.
950  */
951 static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
952 {
953 	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
954 }
955 
956 static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
957 {
958 	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
959 }
960 
961 /*
962  * Values for di_flags
963  * There should be a one-to-one correspondence between these flags and the
964  * XFS_XFLAG_s.
965  */
966 #define XFS_DIFLAG_REALTIME_BIT  0	/* file's blocks come from rt area */
967 #define XFS_DIFLAG_PREALLOC_BIT  1	/* file space has been preallocated */
968 #define XFS_DIFLAG_NEWRTBM_BIT   2	/* for rtbitmap inode, new format */
969 #define XFS_DIFLAG_IMMUTABLE_BIT 3	/* inode is immutable */
970 #define XFS_DIFLAG_APPEND_BIT    4	/* inode is append-only */
971 #define XFS_DIFLAG_SYNC_BIT      5	/* inode is written synchronously */
972 #define XFS_DIFLAG_NOATIME_BIT   6	/* do not update atime */
973 #define XFS_DIFLAG_NODUMP_BIT    7	/* do not dump */
974 #define XFS_DIFLAG_RTINHERIT_BIT 8	/* create with realtime bit set */
975 #define XFS_DIFLAG_PROJINHERIT_BIT   9	/* create with parents projid */
976 #define XFS_DIFLAG_NOSYMLINKS_BIT   10	/* disallow symlink creation */
977 #define XFS_DIFLAG_EXTSIZE_BIT      11	/* inode extent size allocator hint */
978 #define XFS_DIFLAG_EXTSZINHERIT_BIT 12	/* inherit inode extent size */
979 #define XFS_DIFLAG_NODEFRAG_BIT     13	/* do not reorganize/defragment */
980 #define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
981 #define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
982 #define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
983 #define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
984 #define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
985 #define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
986 #define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
987 #define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
988 #define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
989 #define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
990 #define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
991 #define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
992 #define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
993 #define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
994 #define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
995 #define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
996 
997 #define XFS_DIFLAG_ANY \
998 	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
999 	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
1000 	 XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
1001 	 XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
1002 	 XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
1003 
1004 /*
1005  * Inode number format:
1006  * low inopblog bits - offset in block
1007  * next agblklog bits - block number in ag
1008  * next agno_log bits - ag number
1009  * high agno_log-agblklog-inopblog bits - 0
1010  */
1011 #define	XFS_INO_MASK(k)			(__uint32_t)((1ULL << (k)) - 1)
1012 #define	XFS_INO_OFFSET_BITS(mp)		(mp)->m_sb.sb_inopblog
1013 #define	XFS_INO_AGBNO_BITS(mp)		(mp)->m_sb.sb_agblklog
1014 #define	XFS_INO_AGINO_BITS(mp)		(mp)->m_agino_log
1015 #define	XFS_INO_AGNO_BITS(mp)		(mp)->m_agno_log
1016 #define	XFS_INO_BITS(mp)		\
1017 	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1018 #define	XFS_INO_TO_AGNO(mp,i)		\
1019 	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1020 #define	XFS_INO_TO_AGINO(mp,i)		\
1021 	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1022 #define	XFS_INO_TO_AGBNO(mp,i)		\
1023 	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1024 		XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1025 #define	XFS_INO_TO_OFFSET(mp,i)		\
1026 	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1027 #define	XFS_INO_TO_FSB(mp,i)		\
1028 	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1029 #define	XFS_AGINO_TO_INO(mp,a,i)	\
1030 	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1031 #define	XFS_AGINO_TO_AGBNO(mp,i)	((i) >> XFS_INO_OFFSET_BITS(mp))
1032 #define	XFS_AGINO_TO_OFFSET(mp,i)	\
1033 	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1034 #define	XFS_OFFBNO_TO_AGINO(mp,b,o)	\
1035 	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1036 
1037 #define	XFS_MAXINUMBER		((xfs_ino_t)((1ULL << 56) - 1ULL))
1038 #define	XFS_MAXINUMBER_32	((xfs_ino_t)((1ULL << 32) - 1ULL))
1039 
1040 /*
1041  * RealTime Device format definitions
1042  */
1043 
1044 /* Min and max rt extent sizes, specified in bytes */
1045 #define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
1046 #define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
1047 #define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */
1048 
1049 #define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
1050 #define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
1051 #define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
1052 #define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
1053 
1054 /*
1055  * RT Summary and bit manipulation macros.
1056  */
1057 #define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
1058 #define	XFS_SUMOFFSTOBLOCK(mp,s)	\
1059 	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
1060 #define	XFS_SUMPTR(mp,bp,so)	\
1061 	((xfs_suminfo_t *)((bp)->b_addr + \
1062 		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
1063 
1064 #define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
1065 #define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
1066 #define	XFS_BITTOWORD(mp,bi)	\
1067 	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
1068 
1069 #define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
1070 #define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
1071 
1072 #define	XFS_RTLOBIT(w)	xfs_lowbit32(w)
1073 #define	XFS_RTHIBIT(w)	xfs_highbit32(w)
1074 
1075 #define	XFS_RTBLOCKLOG(b)	xfs_highbit64(b)
1076 
1077 /*
1078  * Dquot and dquot block format definitions
1079  */
1080 #define XFS_DQUOT_MAGIC		0x4451		/* 'DQ' */
1081 #define XFS_DQUOT_VERSION	(u_int8_t)0x01	/* latest version number */
1082 
1083 /*
1084  * This is the main portion of the on-disk representation of quota
1085  * information for a user. This is the q_core of the xfs_dquot_t that
1086  * is kept in kernel memory. We pad this with some more expansion room
1087  * to construct the on disk structure.
1088  */
1089 typedef struct	xfs_disk_dquot {
1090 	__be16		d_magic;	/* dquot magic = XFS_DQUOT_MAGIC */
1091 	__u8		d_version;	/* dquot version */
1092 	__u8		d_flags;	/* XFS_DQ_USER/PROJ/GROUP */
1093 	__be32		d_id;		/* user,project,group id */
1094 	__be64		d_blk_hardlimit;/* absolute limit on disk blks */
1095 	__be64		d_blk_softlimit;/* preferred limit on disk blks */
1096 	__be64		d_ino_hardlimit;/* maximum # allocated inodes */
1097 	__be64		d_ino_softlimit;/* preferred inode limit */
1098 	__be64		d_bcount;	/* disk blocks owned by the user */
1099 	__be64		d_icount;	/* inodes owned by the user */
1100 	__be32		d_itimer;	/* zero if within inode limits if not,
1101 					   this is when we refuse service */
1102 	__be32		d_btimer;	/* similar to above; for disk blocks */
1103 	__be16		d_iwarns;	/* warnings issued wrt num inodes */
1104 	__be16		d_bwarns;	/* warnings issued wrt disk blocks */
1105 	__be32		d_pad0;		/* 64 bit align */
1106 	__be64		d_rtb_hardlimit;/* absolute limit on realtime blks */
1107 	__be64		d_rtb_softlimit;/* preferred limit on RT disk blks */
1108 	__be64		d_rtbcount;	/* realtime blocks owned */
1109 	__be32		d_rtbtimer;	/* similar to above; for RT disk blocks */
1110 	__be16		d_rtbwarns;	/* warnings issued wrt RT disk blocks */
1111 	__be16		d_pad;
1112 } xfs_disk_dquot_t;
1113 
1114 /*
1115  * This is what goes on disk. This is separated from the xfs_disk_dquot because
1116  * carrying the unnecessary padding would be a waste of memory.
1117  */
1118 typedef struct xfs_dqblk {
1119 	xfs_disk_dquot_t  dd_diskdq;	/* portion that lives incore as well */
1120 	char		  dd_fill[4];	/* filling for posterity */
1121 
1122 	/*
1123 	 * These two are only present on filesystems with the CRC bits set.
1124 	 */
1125 	__be32		  dd_crc;	/* checksum */
1126 	__be64		  dd_lsn;	/* last modification in log */
1127 	uuid_t		  dd_uuid;	/* location information */
1128 } xfs_dqblk_t;
1129 
1130 #define XFS_DQUOT_CRC_OFF	offsetof(struct xfs_dqblk, dd_crc)
1131 
1132 /*
1133  * Remote symlink format and access functions.
1134  */
1135 #define XFS_SYMLINK_MAGIC	0x58534c4d	/* XSLM */
1136 
1137 struct xfs_dsymlink_hdr {
1138 	__be32	sl_magic;
1139 	__be32	sl_offset;
1140 	__be32	sl_bytes;
1141 	__be32	sl_crc;
1142 	uuid_t	sl_uuid;
1143 	__be64	sl_owner;
1144 	__be64	sl_blkno;
1145 	__be64	sl_lsn;
1146 };
1147 
1148 #define XFS_SYMLINK_CRC_OFF	offsetof(struct xfs_dsymlink_hdr, sl_crc)
1149 
1150 /*
1151  * The maximum pathlen is 1024 bytes. Since the minimum file system
1152  * blocksize is 512 bytes, we can get a max of 3 extents back from
1153  * bmapi when crc headers are taken into account.
1154  */
1155 #define XFS_SYMLINK_MAPS 3
1156 
1157 #define XFS_SYMLINK_BUF_SPACE(mp, bufsize)	\
1158 	((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
1159 			sizeof(struct xfs_dsymlink_hdr) : 0))
1160 
1161 
1162 /*
1163  * Allocation Btree format definitions
1164  *
1165  * There are two on-disk btrees, one sorted by blockno and one sorted
1166  * by blockcount and blockno.  All blocks look the same to make the code
1167  * simpler; if we have time later, we'll make the optimizations.
1168  */
1169 #define	XFS_ABTB_MAGIC		0x41425442	/* 'ABTB' for bno tree */
1170 #define	XFS_ABTB_CRC_MAGIC	0x41423342	/* 'AB3B' */
1171 #define	XFS_ABTC_MAGIC		0x41425443	/* 'ABTC' for cnt tree */
1172 #define	XFS_ABTC_CRC_MAGIC	0x41423343	/* 'AB3C' */
1173 
1174 /*
1175  * Data record/key structure
1176  */
1177 typedef struct xfs_alloc_rec {
1178 	__be32		ar_startblock;	/* starting block number */
1179 	__be32		ar_blockcount;	/* count of free blocks */
1180 } xfs_alloc_rec_t, xfs_alloc_key_t;
1181 
1182 typedef struct xfs_alloc_rec_incore {
1183 	xfs_agblock_t	ar_startblock;	/* starting block number */
1184 	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
1185 } xfs_alloc_rec_incore_t;
1186 
1187 /* btree pointer type */
1188 typedef __be32 xfs_alloc_ptr_t;
1189 
1190 /*
1191  * Block numbers in the AG:
1192  * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1193  */
1194 #define	XFS_BNO_BLOCK(mp)	((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1195 #define	XFS_CNT_BLOCK(mp)	((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1196 
1197 
1198 /*
1199  * Inode Allocation Btree format definitions
1200  *
1201  * There is a btree for the inode map per allocation group.
1202  */
1203 #define	XFS_IBT_MAGIC		0x49414254	/* 'IABT' */
1204 #define	XFS_IBT_CRC_MAGIC	0x49414233	/* 'IAB3' */
1205 #define	XFS_FIBT_MAGIC		0x46494254	/* 'FIBT' */
1206 #define	XFS_FIBT_CRC_MAGIC	0x46494233	/* 'FIB3' */
1207 
1208 typedef	__uint64_t	xfs_inofree_t;
1209 #define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
1210 #define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
1211 #define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
1212 #define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
1213 
1214 #define XFS_INOBT_HOLEMASK_FULL		0	/* holemask for full chunk */
1215 #define XFS_INOBT_HOLEMASK_BITS		(NBBY * sizeof(__uint16_t))
1216 #define XFS_INODES_PER_HOLEMASK_BIT	\
1217 	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(__uint16_t)))
1218 
1219 static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1220 {
1221 	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1222 }
1223 
1224 /*
1225  * The on-disk inode record structure has two formats. The original "full"
1226  * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1227  * and replaces the 3 high-order freecount bytes wth the holemask and inode
1228  * count.
1229  *
1230  * The holemask of the sparse record format allows an inode chunk to have holes
1231  * that refer to blocks not owned by the inode record. This facilitates inode
1232  * allocation in the event of severe free space fragmentation.
1233  */
1234 typedef struct xfs_inobt_rec {
1235 	__be32		ir_startino;	/* starting inode number */
1236 	union {
1237 		struct {
1238 			__be32	ir_freecount;	/* count of free inodes */
1239 		} f;
1240 		struct {
1241 			__be16	ir_holemask;/* hole mask for sparse chunks */
1242 			__u8	ir_count;	/* total inode count */
1243 			__u8	ir_freecount;	/* count of free inodes */
1244 		} sp;
1245 	} ir_u;
1246 	__be64		ir_free;	/* free inode mask */
1247 } xfs_inobt_rec_t;
1248 
1249 typedef struct xfs_inobt_rec_incore {
1250 	xfs_agino_t	ir_startino;	/* starting inode number */
1251 	__uint16_t	ir_holemask;	/* hole mask for sparse chunks */
1252 	__uint8_t	ir_count;	/* total inode count */
1253 	__uint8_t	ir_freecount;	/* count of free inodes (set bits) */
1254 	xfs_inofree_t	ir_free;	/* free inode mask */
1255 } xfs_inobt_rec_incore_t;
1256 
1257 static inline bool xfs_inobt_issparse(uint16_t holemask)
1258 {
1259 	/* non-zero holemask represents a sparse rec. */
1260 	return holemask;
1261 }
1262 
1263 /*
1264  * Key structure
1265  */
1266 typedef struct xfs_inobt_key {
1267 	__be32		ir_startino;	/* starting inode number */
1268 } xfs_inobt_key_t;
1269 
1270 /* btree pointer type */
1271 typedef __be32 xfs_inobt_ptr_t;
1272 
1273 /*
1274  * block numbers in the AG.
1275  */
1276 #define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1277 #define	XFS_FIBT_BLOCK(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1278 
1279 /*
1280  * The first data block of an AG depends on whether the filesystem was formatted
1281  * with the finobt feature. If so, account for the finobt reserved root btree
1282  * block.
1283  */
1284 #define XFS_PREALLOC_BLOCKS(mp) \
1285 	(xfs_sb_version_hasfinobt(&((mp)->m_sb)) ? \
1286 	 XFS_FIBT_BLOCK(mp) + 1 : \
1287 	 XFS_IBT_BLOCK(mp) + 1)
1288 
1289 
1290 
1291 /*
1292  * BMAP Btree format definitions
1293  *
1294  * This includes both the root block definition that sits inside an inode fork
1295  * and the record/pointer formats for the leaf/node in the blocks.
1296  */
1297 #define XFS_BMAP_MAGIC		0x424d4150	/* 'BMAP' */
1298 #define XFS_BMAP_CRC_MAGIC	0x424d4133	/* 'BMA3' */
1299 
1300 /*
1301  * Bmap root header, on-disk form only.
1302  */
1303 typedef struct xfs_bmdr_block {
1304 	__be16		bb_level;	/* 0 is a leaf */
1305 	__be16		bb_numrecs;	/* current # of data records */
1306 } xfs_bmdr_block_t;
1307 
1308 /*
1309  * Bmap btree record and extent descriptor.
1310  *  l0:63 is an extent flag (value 1 indicates non-normal).
1311  *  l0:9-62 are startoff.
1312  *  l0:0-8 and l1:21-63 are startblock.
1313  *  l1:0-20 are blockcount.
1314  */
1315 #define BMBT_EXNTFLAG_BITLEN	1
1316 #define BMBT_STARTOFF_BITLEN	54
1317 #define BMBT_STARTBLOCK_BITLEN	52
1318 #define BMBT_BLOCKCOUNT_BITLEN	21
1319 
1320 typedef struct xfs_bmbt_rec {
1321 	__be64			l0, l1;
1322 } xfs_bmbt_rec_t;
1323 
1324 typedef __uint64_t	xfs_bmbt_rec_base_t;	/* use this for casts */
1325 typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1326 
1327 typedef struct xfs_bmbt_rec_host {
1328 	__uint64_t		l0, l1;
1329 } xfs_bmbt_rec_host_t;
1330 
1331 /*
1332  * Values and macros for delayed-allocation startblock fields.
1333  */
1334 #define STARTBLOCKVALBITS	17
1335 #define STARTBLOCKMASKBITS	(15 + 20)
1336 #define STARTBLOCKMASK		\
1337 	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1338 
1339 static inline int isnullstartblock(xfs_fsblock_t x)
1340 {
1341 	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1342 }
1343 
1344 static inline xfs_fsblock_t nullstartblock(int k)
1345 {
1346 	ASSERT(k < (1 << STARTBLOCKVALBITS));
1347 	return STARTBLOCKMASK | (k);
1348 }
1349 
1350 static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1351 {
1352 	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1353 }
1354 
1355 /*
1356  * Possible extent formats.
1357  */
1358 typedef enum {
1359 	XFS_EXTFMT_NOSTATE = 0,
1360 	XFS_EXTFMT_HASSTATE
1361 } xfs_exntfmt_t;
1362 
1363 /*
1364  * Possible extent states.
1365  */
1366 typedef enum {
1367 	XFS_EXT_NORM, XFS_EXT_UNWRITTEN,
1368 	XFS_EXT_DMAPI_OFFLINE, XFS_EXT_INVALID
1369 } xfs_exntst_t;
1370 
1371 /*
1372  * Incore version of above.
1373  */
1374 typedef struct xfs_bmbt_irec
1375 {
1376 	xfs_fileoff_t	br_startoff;	/* starting file offset */
1377 	xfs_fsblock_t	br_startblock;	/* starting block number */
1378 	xfs_filblks_t	br_blockcount;	/* number of blocks */
1379 	xfs_exntst_t	br_state;	/* extent state */
1380 } xfs_bmbt_irec_t;
1381 
1382 /*
1383  * Key structure for non-leaf levels of the tree.
1384  */
1385 typedef struct xfs_bmbt_key {
1386 	__be64		br_startoff;	/* starting file offset */
1387 } xfs_bmbt_key_t, xfs_bmdr_key_t;
1388 
1389 /* btree pointer type */
1390 typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1391 
1392 
1393 /*
1394  * Generic Btree block format definitions
1395  *
1396  * This is a combination of the actual format used on disk for short and long
1397  * format btrees.  The first three fields are shared by both format, but the
1398  * pointers are different and should be used with care.
1399  *
1400  * To get the size of the actual short or long form headers please use the size
1401  * macros below.  Never use sizeof(xfs_btree_block).
1402  *
1403  * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1404  * with the crc feature bit, and all accesses to them must be conditional on
1405  * that flag.
1406  */
1407 struct xfs_btree_block {
1408 	__be32		bb_magic;	/* magic number for block type */
1409 	__be16		bb_level;	/* 0 is a leaf */
1410 	__be16		bb_numrecs;	/* current # of data records */
1411 	union {
1412 		struct {
1413 			__be32		bb_leftsib;
1414 			__be32		bb_rightsib;
1415 
1416 			__be64		bb_blkno;
1417 			__be64		bb_lsn;
1418 			uuid_t		bb_uuid;
1419 			__be32		bb_owner;
1420 			__le32		bb_crc;
1421 		} s;			/* short form pointers */
1422 		struct	{
1423 			__be64		bb_leftsib;
1424 			__be64		bb_rightsib;
1425 
1426 			__be64		bb_blkno;
1427 			__be64		bb_lsn;
1428 			uuid_t		bb_uuid;
1429 			__be64		bb_owner;
1430 			__le32		bb_crc;
1431 			__be32		bb_pad; /* padding for alignment */
1432 		} l;			/* long form pointers */
1433 	} bb_u;				/* rest */
1434 };
1435 
1436 #define XFS_BTREE_SBLOCK_LEN	16	/* size of a short form block */
1437 #define XFS_BTREE_LBLOCK_LEN	24	/* size of a long form block */
1438 
1439 /* sizes of CRC enabled btree blocks */
1440 #define XFS_BTREE_SBLOCK_CRC_LEN	(XFS_BTREE_SBLOCK_LEN + 40)
1441 #define XFS_BTREE_LBLOCK_CRC_LEN	(XFS_BTREE_LBLOCK_LEN + 48)
1442 
1443 #define XFS_BTREE_SBLOCK_CRC_OFF \
1444 	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1445 #define XFS_BTREE_LBLOCK_CRC_OFF \
1446 	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1447 
1448 /*
1449  * On-disk XFS access control list structure.
1450  */
1451 struct xfs_acl_entry {
1452 	__be32	ae_tag;
1453 	__be32	ae_id;
1454 	__be16	ae_perm;
1455 	__be16	ae_pad;		/* fill the implicit hole in the structure */
1456 };
1457 
1458 struct xfs_acl {
1459 	__be32			acl_cnt;
1460 	struct xfs_acl_entry	acl_entry[0];
1461 };
1462 
1463 /*
1464  * The number of ACL entries allowed is defined by the on-disk format.
1465  * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
1466  * limited only by the maximum size of the xattr that stores the information.
1467  */
1468 #define XFS_ACL_MAX_ENTRIES(mp)	\
1469 	(xfs_sb_version_hascrc(&mp->m_sb) \
1470 		?  (XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
1471 						sizeof(struct xfs_acl_entry) \
1472 		: 25)
1473 
1474 #define XFS_ACL_MAX_SIZE(mp) \
1475 	(sizeof(struct xfs_acl) + \
1476 		sizeof(struct xfs_acl_entry) * XFS_ACL_MAX_ENTRIES((mp)))
1477 
1478 /* On-disk XFS extended attribute names */
1479 #define SGI_ACL_FILE		"SGI_ACL_FILE"
1480 #define SGI_ACL_DEFAULT		"SGI_ACL_DEFAULT"
1481 #define SGI_ACL_FILE_SIZE	(sizeof(SGI_ACL_FILE)-1)
1482 #define SGI_ACL_DEFAULT_SIZE	(sizeof(SGI_ACL_DEFAULT)-1)
1483 
1484 #endif /* __XFS_FORMAT_H__ */
1485