xref: /linux/fs/xfs/libxfs/xfs_format.h (revision 97733180fafbeb7cc3fd1c8be60d05980615f5d6)
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 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 };
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 static inline bool xfs_sb_is_v5(struct xfs_sb *sbp)
283 {
284 	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
285 }
286 
287 /*
288  * Detect a mismatched features2 field.  Older kernels read/wrote
289  * this into the wrong slot, so to be safe we keep them in sync.
290  */
291 static inline bool xfs_sb_has_mismatched_features2(struct xfs_sb *sbp)
292 {
293 	return sbp->sb_bad_features2 != sbp->sb_features2;
294 }
295 
296 static inline bool xfs_sb_version_hasmorebits(struct xfs_sb *sbp)
297 {
298 	return xfs_sb_is_v5(sbp) ||
299 	       (sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
300 }
301 
302 static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
303 {
304 	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
305 }
306 
307 static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
308 {
309 	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
310 }
311 
312 static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
313 {
314 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
315 	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
316 }
317 
318 static inline void xfs_sb_version_addprojid32(struct xfs_sb *sbp)
319 {
320 	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
321 	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
322 }
323 
324 /*
325  * Extended v5 superblock feature masks. These are to be used for new v5
326  * superblock features only.
327  *
328  * Compat features are new features that old kernels will not notice or affect
329  * and so can mount read-write without issues.
330  *
331  * RO-Compat (read only) are features that old kernels can read but will break
332  * if they write. Hence only read-only mounts of such filesystems are allowed on
333  * kernels that don't support the feature bit.
334  *
335  * InCompat features are features which old kernels will not understand and so
336  * must not mount.
337  *
338  * Log-InCompat features are for changes to log formats or new transactions that
339  * can't be replayed on older kernels. The fields are set when the filesystem is
340  * mounted, and a clean unmount clears the fields.
341  */
342 #define XFS_SB_FEAT_COMPAT_ALL 0
343 #define XFS_SB_FEAT_COMPAT_UNKNOWN	~XFS_SB_FEAT_COMPAT_ALL
344 static inline bool
345 xfs_sb_has_compat_feature(
346 	struct xfs_sb	*sbp,
347 	uint32_t	feature)
348 {
349 	return (sbp->sb_features_compat & feature) != 0;
350 }
351 
352 #define XFS_SB_FEAT_RO_COMPAT_FINOBT   (1 << 0)		/* free inode btree */
353 #define XFS_SB_FEAT_RO_COMPAT_RMAPBT   (1 << 1)		/* reverse map btree */
354 #define XFS_SB_FEAT_RO_COMPAT_REFLINK  (1 << 2)		/* reflinked files */
355 #define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3)		/* inobt block counts */
356 #define XFS_SB_FEAT_RO_COMPAT_ALL \
357 		(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
358 		 XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
359 		 XFS_SB_FEAT_RO_COMPAT_REFLINK| \
360 		 XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
361 #define XFS_SB_FEAT_RO_COMPAT_UNKNOWN	~XFS_SB_FEAT_RO_COMPAT_ALL
362 static inline bool
363 xfs_sb_has_ro_compat_feature(
364 	struct xfs_sb	*sbp,
365 	uint32_t	feature)
366 {
367 	return (sbp->sb_features_ro_compat & feature) != 0;
368 }
369 
370 #define XFS_SB_FEAT_INCOMPAT_FTYPE	(1 << 0)	/* filetype in dirent */
371 #define XFS_SB_FEAT_INCOMPAT_SPINODES	(1 << 1)	/* sparse inode chunks */
372 #define XFS_SB_FEAT_INCOMPAT_META_UUID	(1 << 2)	/* metadata UUID */
373 #define XFS_SB_FEAT_INCOMPAT_BIGTIME	(1 << 3)	/* large timestamps */
374 #define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4)	/* needs xfs_repair */
375 #define XFS_SB_FEAT_INCOMPAT_ALL \
376 		(XFS_SB_FEAT_INCOMPAT_FTYPE|	\
377 		 XFS_SB_FEAT_INCOMPAT_SPINODES|	\
378 		 XFS_SB_FEAT_INCOMPAT_META_UUID| \
379 		 XFS_SB_FEAT_INCOMPAT_BIGTIME| \
380 		 XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR)
381 
382 #define XFS_SB_FEAT_INCOMPAT_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_ALL
383 static inline bool
384 xfs_sb_has_incompat_feature(
385 	struct xfs_sb	*sbp,
386 	uint32_t	feature)
387 {
388 	return (sbp->sb_features_incompat & feature) != 0;
389 }
390 
391 #define XFS_SB_FEAT_INCOMPAT_LOG_ALL 0
392 #define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN	~XFS_SB_FEAT_INCOMPAT_LOG_ALL
393 static inline bool
394 xfs_sb_has_incompat_log_feature(
395 	struct xfs_sb	*sbp,
396 	uint32_t	feature)
397 {
398 	return (sbp->sb_features_log_incompat & feature) != 0;
399 }
400 
401 static inline void
402 xfs_sb_remove_incompat_log_features(
403 	struct xfs_sb	*sbp)
404 {
405 	sbp->sb_features_log_incompat &= ~XFS_SB_FEAT_INCOMPAT_LOG_ALL;
406 }
407 
408 static inline void
409 xfs_sb_add_incompat_log_features(
410 	struct xfs_sb	*sbp,
411 	unsigned int	features)
412 {
413 	sbp->sb_features_log_incompat |= features;
414 }
415 
416 
417 static inline bool
418 xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
419 {
420 	return (ino == sbp->sb_uquotino ||
421 		ino == sbp->sb_gquotino ||
422 		ino == sbp->sb_pquotino);
423 }
424 
425 #define XFS_SB_DADDR		((xfs_daddr_t)0) /* daddr in filesystem/ag */
426 #define	XFS_SB_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
427 
428 #define	XFS_HDR_BLOCK(mp,d)	((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
429 #define	XFS_DADDR_TO_FSB(mp,d)	XFS_AGB_TO_FSB(mp, \
430 			xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
431 #define	XFS_FSB_TO_DADDR(mp,fsbno)	XFS_AGB_TO_DADDR(mp, \
432 			XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
433 
434 /*
435  * File system sector to basic block conversions.
436  */
437 #define XFS_FSS_TO_BB(mp,sec)	((sec) << (mp)->m_sectbb_log)
438 
439 /*
440  * File system block to basic block conversions.
441  */
442 #define	XFS_FSB_TO_BB(mp,fsbno)	((fsbno) << (mp)->m_blkbb_log)
443 #define	XFS_BB_TO_FSB(mp,bb)	\
444 	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
445 #define	XFS_BB_TO_FSBT(mp,bb)	((bb) >> (mp)->m_blkbb_log)
446 
447 /*
448  * File system block to byte conversions.
449  */
450 #define XFS_FSB_TO_B(mp,fsbno)	((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
451 #define XFS_B_TO_FSB(mp,b)	\
452 	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
453 #define XFS_B_TO_FSBT(mp,b)	(((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
454 
455 /*
456  * Allocation group header
457  *
458  * This is divided into three structures, placed in sequential 512-byte
459  * buffers after a copy of the superblock (also in a 512-byte buffer).
460  */
461 #define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
462 #define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
463 #define	XFS_AGFL_MAGIC	0x5841464c	/* 'XAFL' */
464 #define	XFS_AGF_VERSION	1
465 #define	XFS_AGI_VERSION	1
466 
467 #define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
468 #define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
469 
470 /*
471  * Btree number 0 is bno, 1 is cnt, 2 is rmap. This value gives the size of the
472  * arrays below.
473  */
474 #define	XFS_BTNUM_AGF	((int)XFS_BTNUM_RMAPi + 1)
475 
476 /*
477  * The second word of agf_levels in the first a.g. overlaps the EFS
478  * superblock's magic number.  Since the magic numbers valid for EFS
479  * are > 64k, our value cannot be confused for an EFS superblock's.
480  */
481 
482 typedef struct xfs_agf {
483 	/*
484 	 * Common allocation group header information
485 	 */
486 	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
487 	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
488 	__be32		agf_seqno;	/* sequence # starting from 0 */
489 	__be32		agf_length;	/* size in blocks of a.g. */
490 	/*
491 	 * Freespace and rmap information
492 	 */
493 	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
494 	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
495 
496 	__be32		agf_flfirst;	/* first freelist block's index */
497 	__be32		agf_fllast;	/* last freelist block's index */
498 	__be32		agf_flcount;	/* count of blocks in freelist */
499 	__be32		agf_freeblks;	/* total free blocks */
500 
501 	__be32		agf_longest;	/* longest free space */
502 	__be32		agf_btreeblks;	/* # of blocks held in AGF btrees */
503 	uuid_t		agf_uuid;	/* uuid of filesystem */
504 
505 	__be32		agf_rmap_blocks;	/* rmapbt blocks used */
506 	__be32		agf_refcount_blocks;	/* refcountbt blocks used */
507 
508 	__be32		agf_refcount_root;	/* refcount tree root block */
509 	__be32		agf_refcount_level;	/* refcount btree levels */
510 
511 	/*
512 	 * reserve some contiguous space for future logged fields before we add
513 	 * the unlogged fields. This makes the range logging via flags and
514 	 * structure offsets much simpler.
515 	 */
516 	__be64		agf_spare64[14];
517 
518 	/* unlogged fields, written during buffer writeback. */
519 	__be64		agf_lsn;	/* last write sequence */
520 	__be32		agf_crc;	/* crc of agf sector */
521 	__be32		agf_spare2;
522 
523 	/* structure must be padded to 64 bit alignment */
524 } xfs_agf_t;
525 
526 #define XFS_AGF_CRC_OFF		offsetof(struct xfs_agf, agf_crc)
527 
528 #define	XFS_AGF_MAGICNUM	0x00000001
529 #define	XFS_AGF_VERSIONNUM	0x00000002
530 #define	XFS_AGF_SEQNO		0x00000004
531 #define	XFS_AGF_LENGTH		0x00000008
532 #define	XFS_AGF_ROOTS		0x00000010
533 #define	XFS_AGF_LEVELS		0x00000020
534 #define	XFS_AGF_FLFIRST		0x00000040
535 #define	XFS_AGF_FLLAST		0x00000080
536 #define	XFS_AGF_FLCOUNT		0x00000100
537 #define	XFS_AGF_FREEBLKS	0x00000200
538 #define	XFS_AGF_LONGEST		0x00000400
539 #define	XFS_AGF_BTREEBLKS	0x00000800
540 #define	XFS_AGF_UUID		0x00001000
541 #define	XFS_AGF_RMAP_BLOCKS	0x00002000
542 #define	XFS_AGF_REFCOUNT_BLOCKS	0x00004000
543 #define	XFS_AGF_REFCOUNT_ROOT	0x00008000
544 #define	XFS_AGF_REFCOUNT_LEVEL	0x00010000
545 #define	XFS_AGF_SPARE64		0x00020000
546 #define	XFS_AGF_NUM_BITS	18
547 #define	XFS_AGF_ALL_BITS	((1 << XFS_AGF_NUM_BITS) - 1)
548 
549 #define XFS_AGF_FLAGS \
550 	{ XFS_AGF_MAGICNUM,	"MAGICNUM" }, \
551 	{ XFS_AGF_VERSIONNUM,	"VERSIONNUM" }, \
552 	{ XFS_AGF_SEQNO,	"SEQNO" }, \
553 	{ XFS_AGF_LENGTH,	"LENGTH" }, \
554 	{ XFS_AGF_ROOTS,	"ROOTS" }, \
555 	{ XFS_AGF_LEVELS,	"LEVELS" }, \
556 	{ XFS_AGF_FLFIRST,	"FLFIRST" }, \
557 	{ XFS_AGF_FLLAST,	"FLLAST" }, \
558 	{ XFS_AGF_FLCOUNT,	"FLCOUNT" }, \
559 	{ XFS_AGF_FREEBLKS,	"FREEBLKS" }, \
560 	{ XFS_AGF_LONGEST,	"LONGEST" }, \
561 	{ XFS_AGF_BTREEBLKS,	"BTREEBLKS" }, \
562 	{ XFS_AGF_UUID,		"UUID" }, \
563 	{ XFS_AGF_RMAP_BLOCKS,	"RMAP_BLOCKS" }, \
564 	{ XFS_AGF_REFCOUNT_BLOCKS,	"REFCOUNT_BLOCKS" }, \
565 	{ XFS_AGF_REFCOUNT_ROOT,	"REFCOUNT_ROOT" }, \
566 	{ XFS_AGF_REFCOUNT_LEVEL,	"REFCOUNT_LEVEL" }, \
567 	{ XFS_AGF_SPARE64,	"SPARE64" }
568 
569 /* disk block (xfs_daddr_t) in the AG */
570 #define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
571 #define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
572 
573 /*
574  * Size of the unlinked inode hash table in the agi.
575  */
576 #define	XFS_AGI_UNLINKED_BUCKETS	64
577 
578 typedef struct xfs_agi {
579 	/*
580 	 * Common allocation group header information
581 	 */
582 	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
583 	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
584 	__be32		agi_seqno;	/* sequence # starting from 0 */
585 	__be32		agi_length;	/* size in blocks of a.g. */
586 	/*
587 	 * Inode information
588 	 * Inodes are mapped by interpreting the inode number, so no
589 	 * mapping data is needed here.
590 	 */
591 	__be32		agi_count;	/* count of allocated inodes */
592 	__be32		agi_root;	/* root of inode btree */
593 	__be32		agi_level;	/* levels in inode btree */
594 	__be32		agi_freecount;	/* number of free inodes */
595 
596 	__be32		agi_newino;	/* new inode just allocated */
597 	__be32		agi_dirino;	/* last directory inode chunk */
598 	/*
599 	 * Hash table of inodes which have been unlinked but are
600 	 * still being referenced.
601 	 */
602 	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
603 	/*
604 	 * This marks the end of logging region 1 and start of logging region 2.
605 	 */
606 	uuid_t		agi_uuid;	/* uuid of filesystem */
607 	__be32		agi_crc;	/* crc of agi sector */
608 	__be32		agi_pad32;
609 	__be64		agi_lsn;	/* last write sequence */
610 
611 	__be32		agi_free_root; /* root of the free inode btree */
612 	__be32		agi_free_level;/* levels in free inode btree */
613 
614 	__be32		agi_iblocks;	/* inobt blocks used */
615 	__be32		agi_fblocks;	/* finobt blocks used */
616 
617 	/* structure must be padded to 64 bit alignment */
618 } xfs_agi_t;
619 
620 #define XFS_AGI_CRC_OFF		offsetof(struct xfs_agi, agi_crc)
621 
622 #define	XFS_AGI_MAGICNUM	(1 << 0)
623 #define	XFS_AGI_VERSIONNUM	(1 << 1)
624 #define	XFS_AGI_SEQNO		(1 << 2)
625 #define	XFS_AGI_LENGTH		(1 << 3)
626 #define	XFS_AGI_COUNT		(1 << 4)
627 #define	XFS_AGI_ROOT		(1 << 5)
628 #define	XFS_AGI_LEVEL		(1 << 6)
629 #define	XFS_AGI_FREECOUNT	(1 << 7)
630 #define	XFS_AGI_NEWINO		(1 << 8)
631 #define	XFS_AGI_DIRINO		(1 << 9)
632 #define	XFS_AGI_UNLINKED	(1 << 10)
633 #define	XFS_AGI_NUM_BITS_R1	11	/* end of the 1st agi logging region */
634 #define	XFS_AGI_ALL_BITS_R1	((1 << XFS_AGI_NUM_BITS_R1) - 1)
635 #define	XFS_AGI_FREE_ROOT	(1 << 11)
636 #define	XFS_AGI_FREE_LEVEL	(1 << 12)
637 #define	XFS_AGI_IBLOCKS		(1 << 13) /* both inobt/finobt block counters */
638 #define	XFS_AGI_NUM_BITS_R2	14
639 
640 /* disk block (xfs_daddr_t) in the AG */
641 #define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
642 #define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
643 
644 /*
645  * The third a.g. block contains the a.g. freelist, an array
646  * of block pointers to blocks owned by the allocation btree code.
647  */
648 #define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
649 #define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
650 #define	XFS_BUF_TO_AGFL(bp)	((struct xfs_agfl *)((bp)->b_addr))
651 
652 struct xfs_agfl {
653 	__be32		agfl_magicnum;
654 	__be32		agfl_seqno;
655 	uuid_t		agfl_uuid;
656 	__be64		agfl_lsn;
657 	__be32		agfl_crc;
658 } __attribute__((packed));
659 
660 #define XFS_AGFL_CRC_OFF	offsetof(struct xfs_agfl, agfl_crc)
661 
662 #define XFS_AGB_TO_FSB(mp,agno,agbno)	\
663 	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
664 #define	XFS_FSB_TO_AGNO(mp,fsbno)	\
665 	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
666 #define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
667 	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
668 #define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
669 	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
670 		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
671 #define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
672 
673 /*
674  * For checking for bad ranges of xfs_daddr_t's, covering multiple
675  * allocation groups or a single xfs_daddr_t that's a superblock copy.
676  */
677 #define	XFS_AG_CHECK_DADDR(mp,d,len)	\
678 	((len) == 1 ? \
679 	    ASSERT((d) == XFS_SB_DADDR || \
680 		   xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
681 	    ASSERT(xfs_daddr_to_agno(mp, d) == \
682 		   xfs_daddr_to_agno(mp, (d) + (len) - 1)))
683 
684 /*
685  * XFS Timestamps
686  * ==============
687  *
688  * Traditional ondisk inode timestamps consist of signed 32-bit counters for
689  * seconds and nanoseconds; time zero is the Unix epoch, Jan  1 00:00:00 UTC
690  * 1970, which means that the timestamp epoch is the same as the Unix epoch.
691  * Therefore, the ondisk min and max defined here can be used directly to
692  * constrain the incore timestamps on a Unix system.  Note that we actually
693  * encode a __be64 value on disk.
694  *
695  * When the bigtime feature is enabled, ondisk inode timestamps become an
696  * unsigned 64-bit nanoseconds counter.  This means that the bigtime inode
697  * timestamp epoch is the start of the classic timestamp range, which is
698  * Dec 31 20:45:52 UTC 1901.  Because the epochs are not the same, callers
699  * /must/ use the bigtime conversion functions when encoding and decoding raw
700  * timestamps.
701  */
702 typedef __be64 xfs_timestamp_t;
703 
704 /* Legacy timestamp encoding format. */
705 struct xfs_legacy_timestamp {
706 	__be32		t_sec;		/* timestamp seconds */
707 	__be32		t_nsec;		/* timestamp nanoseconds */
708 };
709 
710 /*
711  * Smallest possible ondisk seconds value with traditional timestamps.  This
712  * corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
713  */
714 #define XFS_LEGACY_TIME_MIN	((int64_t)S32_MIN)
715 
716 /*
717  * Largest possible ondisk seconds value with traditional timestamps.  This
718  * corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
719  */
720 #define XFS_LEGACY_TIME_MAX	((int64_t)S32_MAX)
721 
722 /*
723  * Smallest possible ondisk seconds value with bigtime timestamps.  This
724  * corresponds (after conversion to a Unix timestamp) with the traditional
725  * minimum timestamp of Dec 13 20:45:52 UTC 1901.
726  */
727 #define XFS_BIGTIME_TIME_MIN	((int64_t)0)
728 
729 /*
730  * Largest supported ondisk seconds value with bigtime timestamps.  This
731  * corresponds (after conversion to a Unix timestamp) with an incore timestamp
732  * of Jul  2 20:20:24 UTC 2486.
733  *
734  * We round down the ondisk limit so that the bigtime quota and inode max
735  * timestamps will be the same.
736  */
737 #define XFS_BIGTIME_TIME_MAX	((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
738 
739 /*
740  * Bigtime epoch is set exactly to the minimum time value that a traditional
741  * 32-bit timestamp can represent when using the Unix epoch as a reference.
742  * Hence the Unix epoch is at a fixed offset into the supported bigtime
743  * timestamp range.
744  *
745  * The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
746  * timestamp can represent so we will not lose any fidelity in converting
747  * to/from unix and bigtime timestamps.
748  *
749  * The following conversion factor converts a seconds counter from the Unix
750  * epoch to the bigtime epoch.
751  */
752 #define XFS_BIGTIME_EPOCH_OFFSET	(-(int64_t)S32_MIN)
753 
754 /* Convert a timestamp from the Unix epoch to the bigtime epoch. */
755 static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
756 {
757 	return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
758 }
759 
760 /* Convert a timestamp from the bigtime epoch to the Unix epoch. */
761 static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
762 {
763 	return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
764 }
765 
766 /*
767  * On-disk inode structure.
768  *
769  * This is just the header or "dinode core", the inode is expanded to fill a
770  * variable size the leftover area split into a data and an attribute fork.
771  * The format of the data and attribute fork depends on the format of the
772  * inode as indicated by di_format and di_aformat.  To access the data and
773  * attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
774  * below.
775  *
776  * There is a very similar struct xfs_log_dinode which matches the layout of
777  * this structure, but is kept in native format instead of big endian.
778  *
779  * Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
780  * padding field for v3 inodes.
781  */
782 #define	XFS_DINODE_MAGIC		0x494e	/* 'IN' */
783 struct xfs_dinode {
784 	__be16		di_magic;	/* inode magic # = XFS_DINODE_MAGIC */
785 	__be16		di_mode;	/* mode and type of file */
786 	__u8		di_version;	/* inode version */
787 	__u8		di_format;	/* format of di_c data */
788 	__be16		di_onlink;	/* old number of links to file */
789 	__be32		di_uid;		/* owner's user id */
790 	__be32		di_gid;		/* owner's group id */
791 	__be32		di_nlink;	/* number of links to file */
792 	__be16		di_projid_lo;	/* lower part of owner's project id */
793 	__be16		di_projid_hi;	/* higher part owner's project id */
794 	__u8		di_pad[6];	/* unused, zeroed space */
795 	__be16		di_flushiter;	/* incremented on flush */
796 	xfs_timestamp_t	di_atime;	/* time last accessed */
797 	xfs_timestamp_t	di_mtime;	/* time last modified */
798 	xfs_timestamp_t	di_ctime;	/* time created/inode modified */
799 	__be64		di_size;	/* number of bytes in file */
800 	__be64		di_nblocks;	/* # of direct & btree blocks used */
801 	__be32		di_extsize;	/* basic/minimum extent size for file */
802 	__be32		di_nextents;	/* number of extents in data fork */
803 	__be16		di_anextents;	/* number of extents in attribute fork*/
804 	__u8		di_forkoff;	/* attr fork offs, <<3 for 64b align */
805 	__s8		di_aformat;	/* format of attr fork's data */
806 	__be32		di_dmevmask;	/* DMIG event mask */
807 	__be16		di_dmstate;	/* DMIG state info */
808 	__be16		di_flags;	/* random flags, XFS_DIFLAG_... */
809 	__be32		di_gen;		/* generation number */
810 
811 	/* di_next_unlinked is the only non-core field in the old dinode */
812 	__be32		di_next_unlinked;/* agi unlinked list ptr */
813 
814 	/* start of the extended dinode, writable fields */
815 	__le32		di_crc;		/* CRC of the inode */
816 	__be64		di_changecount;	/* number of attribute changes */
817 	__be64		di_lsn;		/* flush sequence */
818 	__be64		di_flags2;	/* more random flags */
819 	__be32		di_cowextsize;	/* basic cow extent size for file */
820 	__u8		di_pad2[12];	/* more padding for future expansion */
821 
822 	/* fields only written to during inode creation */
823 	xfs_timestamp_t	di_crtime;	/* time created */
824 	__be64		di_ino;		/* inode number */
825 	uuid_t		di_uuid;	/* UUID of the filesystem */
826 
827 	/* structure must be padded to 64 bit alignment */
828 };
829 
830 #define XFS_DINODE_CRC_OFF	offsetof(struct xfs_dinode, di_crc)
831 
832 #define DI_MAX_FLUSH 0xffff
833 
834 /*
835  * Size of the core inode on disk.  Version 1 and 2 inodes have
836  * the same size, but version 3 has grown a few additional fields.
837  */
838 static inline uint xfs_dinode_size(int version)
839 {
840 	if (version == 3)
841 		return sizeof(struct xfs_dinode);
842 	return offsetof(struct xfs_dinode, di_crc);
843 }
844 
845 /*
846  * The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
847  * Since the pathconf interface is signed, we use 2^31 - 1 instead.
848  */
849 #define	XFS_MAXLINK		((1U << 31) - 1U)
850 
851 /*
852  * Values for di_format
853  *
854  * This enum is used in string mapping in xfs_trace.h; please keep the
855  * TRACE_DEFINE_ENUMs for it up to date.
856  */
857 enum xfs_dinode_fmt {
858 	XFS_DINODE_FMT_DEV,		/* xfs_dev_t */
859 	XFS_DINODE_FMT_LOCAL,		/* bulk data */
860 	XFS_DINODE_FMT_EXTENTS,		/* struct xfs_bmbt_rec */
861 	XFS_DINODE_FMT_BTREE,		/* struct xfs_bmdr_block */
862 	XFS_DINODE_FMT_UUID		/* added long ago, but never used */
863 };
864 
865 #define XFS_INODE_FORMAT_STR \
866 	{ XFS_DINODE_FMT_DEV,		"dev" }, \
867 	{ XFS_DINODE_FMT_LOCAL,		"local" }, \
868 	{ XFS_DINODE_FMT_EXTENTS,	"extent" }, \
869 	{ XFS_DINODE_FMT_BTREE,		"btree" }, \
870 	{ XFS_DINODE_FMT_UUID,		"uuid" }
871 
872 /*
873  * Inode minimum and maximum sizes.
874  */
875 #define	XFS_DINODE_MIN_LOG	8
876 #define	XFS_DINODE_MAX_LOG	11
877 #define	XFS_DINODE_MIN_SIZE	(1 << XFS_DINODE_MIN_LOG)
878 #define	XFS_DINODE_MAX_SIZE	(1 << XFS_DINODE_MAX_LOG)
879 
880 /*
881  * Inode size for given fs.
882  */
883 #define XFS_DINODE_SIZE(mp) \
884 	(xfs_has_v3inodes(mp) ? \
885 		sizeof(struct xfs_dinode) : \
886 		offsetof(struct xfs_dinode, di_crc))
887 #define XFS_LITINO(mp) \
888 	((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(mp))
889 
890 /*
891  * Inode data & attribute fork sizes, per inode.
892  */
893 #define XFS_DFORK_BOFF(dip)		((int)((dip)->di_forkoff << 3))
894 
895 #define XFS_DFORK_DSIZE(dip,mp) \
896 	((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
897 #define XFS_DFORK_ASIZE(dip,mp) \
898 	((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
899 #define XFS_DFORK_SIZE(dip,mp,w) \
900 	((w) == XFS_DATA_FORK ? \
901 		XFS_DFORK_DSIZE(dip, mp) : \
902 		XFS_DFORK_ASIZE(dip, mp))
903 
904 #define XFS_DFORK_MAXEXT(dip, mp, w) \
905 	(XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
906 
907 /*
908  * Return pointers to the data or attribute forks.
909  */
910 #define XFS_DFORK_DPTR(dip) \
911 	((char *)dip + xfs_dinode_size(dip->di_version))
912 #define XFS_DFORK_APTR(dip)	\
913 	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
914 #define XFS_DFORK_PTR(dip,w)	\
915 	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
916 
917 #define XFS_DFORK_FORMAT(dip,w) \
918 	((w) == XFS_DATA_FORK ? \
919 		(dip)->di_format : \
920 		(dip)->di_aformat)
921 #define XFS_DFORK_NEXTENTS(dip,w) \
922 	((w) == XFS_DATA_FORK ? \
923 		be32_to_cpu((dip)->di_nextents) : \
924 		be16_to_cpu((dip)->di_anextents))
925 
926 /*
927  * For block and character special files the 32bit dev_t is stored at the
928  * beginning of the data fork.
929  */
930 static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
931 {
932 	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
933 }
934 
935 static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
936 {
937 	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
938 }
939 
940 /*
941  * Values for di_flags
942  */
943 #define XFS_DIFLAG_REALTIME_BIT  0	/* file's blocks come from rt area */
944 #define XFS_DIFLAG_PREALLOC_BIT  1	/* file space has been preallocated */
945 #define XFS_DIFLAG_NEWRTBM_BIT   2	/* for rtbitmap inode, new format */
946 #define XFS_DIFLAG_IMMUTABLE_BIT 3	/* inode is immutable */
947 #define XFS_DIFLAG_APPEND_BIT    4	/* inode is append-only */
948 #define XFS_DIFLAG_SYNC_BIT      5	/* inode is written synchronously */
949 #define XFS_DIFLAG_NOATIME_BIT   6	/* do not update atime */
950 #define XFS_DIFLAG_NODUMP_BIT    7	/* do not dump */
951 #define XFS_DIFLAG_RTINHERIT_BIT 8	/* create with realtime bit set */
952 #define XFS_DIFLAG_PROJINHERIT_BIT   9	/* create with parents projid */
953 #define XFS_DIFLAG_NOSYMLINKS_BIT   10	/* disallow symlink creation */
954 #define XFS_DIFLAG_EXTSIZE_BIT      11	/* inode extent size allocator hint */
955 #define XFS_DIFLAG_EXTSZINHERIT_BIT 12	/* inherit inode extent size */
956 #define XFS_DIFLAG_NODEFRAG_BIT     13	/* do not reorganize/defragment */
957 #define XFS_DIFLAG_FILESTREAM_BIT   14  /* use filestream allocator */
958 /* Do not use bit 15, di_flags is legacy and unchanging now */
959 
960 #define XFS_DIFLAG_REALTIME      (1 << XFS_DIFLAG_REALTIME_BIT)
961 #define XFS_DIFLAG_PREALLOC      (1 << XFS_DIFLAG_PREALLOC_BIT)
962 #define XFS_DIFLAG_NEWRTBM       (1 << XFS_DIFLAG_NEWRTBM_BIT)
963 #define XFS_DIFLAG_IMMUTABLE     (1 << XFS_DIFLAG_IMMUTABLE_BIT)
964 #define XFS_DIFLAG_APPEND        (1 << XFS_DIFLAG_APPEND_BIT)
965 #define XFS_DIFLAG_SYNC          (1 << XFS_DIFLAG_SYNC_BIT)
966 #define XFS_DIFLAG_NOATIME       (1 << XFS_DIFLAG_NOATIME_BIT)
967 #define XFS_DIFLAG_NODUMP        (1 << XFS_DIFLAG_NODUMP_BIT)
968 #define XFS_DIFLAG_RTINHERIT     (1 << XFS_DIFLAG_RTINHERIT_BIT)
969 #define XFS_DIFLAG_PROJINHERIT   (1 << XFS_DIFLAG_PROJINHERIT_BIT)
970 #define XFS_DIFLAG_NOSYMLINKS    (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
971 #define XFS_DIFLAG_EXTSIZE       (1 << XFS_DIFLAG_EXTSIZE_BIT)
972 #define XFS_DIFLAG_EXTSZINHERIT  (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
973 #define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
974 #define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
975 
976 #define XFS_DIFLAG_ANY \
977 	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
978 	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
979 	 XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
980 	 XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
981 	 XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
982 
983 /*
984  * Values for di_flags2 These start by being exposed to userspace in the upper
985  * 16 bits of the XFS_XFLAG_s range.
986  */
987 #define XFS_DIFLAG2_DAX_BIT	0	/* use DAX for this inode */
988 #define XFS_DIFLAG2_REFLINK_BIT	1	/* file's blocks may be shared */
989 #define XFS_DIFLAG2_COWEXTSIZE_BIT   2  /* copy on write extent size hint */
990 #define XFS_DIFLAG2_BIGTIME_BIT	3	/* big timestamps */
991 
992 #define XFS_DIFLAG2_DAX		(1 << XFS_DIFLAG2_DAX_BIT)
993 #define XFS_DIFLAG2_REFLINK     (1 << XFS_DIFLAG2_REFLINK_BIT)
994 #define XFS_DIFLAG2_COWEXTSIZE  (1 << XFS_DIFLAG2_COWEXTSIZE_BIT)
995 #define XFS_DIFLAG2_BIGTIME	(1 << XFS_DIFLAG2_BIGTIME_BIT)
996 
997 #define XFS_DIFLAG2_ANY \
998 	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
999 	 XFS_DIFLAG2_BIGTIME)
1000 
1001 static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
1002 {
1003 	return dip->di_version >= 3 &&
1004 	       (dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
1005 }
1006 
1007 /*
1008  * Inode number format:
1009  * low inopblog bits - offset in block
1010  * next agblklog bits - block number in ag
1011  * next agno_log bits - ag number
1012  * high agno_log-agblklog-inopblog bits - 0
1013  */
1014 #define	XFS_INO_MASK(k)			(uint32_t)((1ULL << (k)) - 1)
1015 #define	XFS_INO_OFFSET_BITS(mp)		(mp)->m_sb.sb_inopblog
1016 #define	XFS_INO_AGBNO_BITS(mp)		(mp)->m_sb.sb_agblklog
1017 #define	XFS_INO_AGINO_BITS(mp)		((mp)->m_ino_geo.agino_log)
1018 #define	XFS_INO_AGNO_BITS(mp)		(mp)->m_agno_log
1019 #define	XFS_INO_BITS(mp)		\
1020 	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1021 #define	XFS_INO_TO_AGNO(mp,i)		\
1022 	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1023 #define	XFS_INO_TO_AGINO(mp,i)		\
1024 	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1025 #define	XFS_INO_TO_AGBNO(mp,i)		\
1026 	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1027 		XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1028 #define	XFS_INO_TO_OFFSET(mp,i)		\
1029 	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1030 #define	XFS_INO_TO_FSB(mp,i)		\
1031 	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1032 #define	XFS_AGINO_TO_INO(mp,a,i)	\
1033 	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1034 #define	XFS_AGINO_TO_AGBNO(mp,i)	((i) >> XFS_INO_OFFSET_BITS(mp))
1035 #define	XFS_AGINO_TO_OFFSET(mp,i)	\
1036 	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1037 #define	XFS_OFFBNO_TO_AGINO(mp,b,o)	\
1038 	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1039 #define	XFS_FSB_TO_INO(mp, b)	((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1040 #define	XFS_AGB_TO_AGINO(mp, b)	((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1041 
1042 #define	XFS_MAXINUMBER		((xfs_ino_t)((1ULL << 56) - 1ULL))
1043 #define	XFS_MAXINUMBER_32	((xfs_ino_t)((1ULL << 32) - 1ULL))
1044 
1045 /*
1046  * RealTime Device format definitions
1047  */
1048 
1049 /* Min and max rt extent sizes, specified in bytes */
1050 #define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
1051 #define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64kB */
1052 #define	XFS_MIN_RTEXTSIZE	(4 * 1024)		/* 4kB */
1053 
1054 #define	XFS_BLOCKSIZE(mp)	((mp)->m_sb.sb_blocksize)
1055 #define	XFS_BLOCKMASK(mp)	((mp)->m_blockmask)
1056 #define	XFS_BLOCKWSIZE(mp)	((mp)->m_blockwsize)
1057 #define	XFS_BLOCKWMASK(mp)	((mp)->m_blockwmask)
1058 
1059 /*
1060  * RT Summary and bit manipulation macros.
1061  */
1062 #define	XFS_SUMOFFS(mp,ls,bb)	((int)((ls) * (mp)->m_sb.sb_rbmblocks + (bb)))
1063 #define	XFS_SUMOFFSTOBLOCK(mp,s)	\
1064 	(((s) * (uint)sizeof(xfs_suminfo_t)) >> (mp)->m_sb.sb_blocklog)
1065 #define	XFS_SUMPTR(mp,bp,so)	\
1066 	((xfs_suminfo_t *)((bp)->b_addr + \
1067 		(((so) * (uint)sizeof(xfs_suminfo_t)) & XFS_BLOCKMASK(mp))))
1068 
1069 #define	XFS_BITTOBLOCK(mp,bi)	((bi) >> (mp)->m_blkbit_log)
1070 #define	XFS_BLOCKTOBIT(mp,bb)	((bb) << (mp)->m_blkbit_log)
1071 #define	XFS_BITTOWORD(mp,bi)	\
1072 	((int)(((bi) >> XFS_NBWORDLOG) & XFS_BLOCKWMASK(mp)))
1073 
1074 #define	XFS_RTMIN(a,b)	((a) < (b) ? (a) : (b))
1075 #define	XFS_RTMAX(a,b)	((a) > (b) ? (a) : (b))
1076 
1077 #define	XFS_RTLOBIT(w)	xfs_lowbit32(w)
1078 #define	XFS_RTHIBIT(w)	xfs_highbit32(w)
1079 
1080 #define	XFS_RTBLOCKLOG(b)	xfs_highbit64(b)
1081 
1082 /*
1083  * Dquot and dquot block format definitions
1084  */
1085 #define XFS_DQUOT_MAGIC		0x4451		/* 'DQ' */
1086 #define XFS_DQUOT_VERSION	(uint8_t)0x01	/* latest version number */
1087 
1088 #define XFS_DQTYPE_USER		0x01		/* user dquot record */
1089 #define XFS_DQTYPE_PROJ		0x02		/* project dquot record */
1090 #define XFS_DQTYPE_GROUP	0x04		/* group dquot record */
1091 #define XFS_DQTYPE_BIGTIME	0x80		/* large expiry timestamps */
1092 
1093 /* bitmask to determine if this is a user/group/project dquot */
1094 #define XFS_DQTYPE_REC_MASK	(XFS_DQTYPE_USER | \
1095 				 XFS_DQTYPE_PROJ | \
1096 				 XFS_DQTYPE_GROUP)
1097 
1098 #define XFS_DQTYPE_ANY		(XFS_DQTYPE_REC_MASK | \
1099 				 XFS_DQTYPE_BIGTIME)
1100 
1101 /*
1102  * XFS Quota Timers
1103  * ================
1104  *
1105  * Traditional quota grace period expiration timers are an unsigned 32-bit
1106  * seconds counter; time zero is the Unix epoch, Jan  1 00:00:01 UTC 1970.
1107  * Note that an expiration value of zero means that the quota limit has not
1108  * been reached, and therefore no expiration has been set.  Therefore, the
1109  * ondisk min and max defined here can be used directly to constrain the incore
1110  * quota expiration timestamps on a Unix system.
1111  *
1112  * When bigtime is enabled, we trade two bits of precision to expand the
1113  * expiration timeout range to match that of big inode timestamps.  The min and
1114  * max recorded here are the on-disk limits, not a Unix timestamp.
1115  *
1116  * The grace period for each quota type is stored in the root dquot (id = 0)
1117  * and is applied to a non-root dquot when it exceeds the soft or hard limits.
1118  * The length of quota grace periods are unsigned 32-bit quantities measured in
1119  * units of seconds.  A value of zero means to use the default period.
1120  */
1121 
1122 /*
1123  * Smallest possible ondisk quota expiration value with traditional timestamps.
1124  * This corresponds exactly with the incore expiration Jan  1 00:00:01 UTC 1970.
1125  */
1126 #define XFS_DQ_LEGACY_EXPIRY_MIN	((int64_t)1)
1127 
1128 /*
1129  * Largest possible ondisk quota expiration value with traditional timestamps.
1130  * This corresponds exactly with the incore expiration Feb  7 06:28:15 UTC 2106.
1131  */
1132 #define XFS_DQ_LEGACY_EXPIRY_MAX	((int64_t)U32_MAX)
1133 
1134 /*
1135  * Smallest possible ondisk quota expiration value with bigtime timestamps.
1136  * This corresponds (after conversion to a Unix timestamp) with the incore
1137  * expiration of Jan  1 00:00:04 UTC 1970.
1138  */
1139 #define XFS_DQ_BIGTIME_EXPIRY_MIN	(XFS_DQ_LEGACY_EXPIRY_MIN)
1140 
1141 /*
1142  * Largest supported ondisk quota expiration value with bigtime timestamps.
1143  * This corresponds (after conversion to a Unix timestamp) with an incore
1144  * expiration of Jul  2 20:20:24 UTC 2486.
1145  *
1146  * The ondisk field supports values up to -1U, which corresponds to an incore
1147  * expiration in 2514.  This is beyond the maximum the bigtime inode timestamp,
1148  * so we cap the maximum bigtime quota expiration to the max inode timestamp.
1149  */
1150 #define XFS_DQ_BIGTIME_EXPIRY_MAX	((int64_t)4074815106U)
1151 
1152 /*
1153  * The following conversion factors assist in converting a quota expiration
1154  * timestamp between the incore and ondisk formats.
1155  */
1156 #define XFS_DQ_BIGTIME_SHIFT	(2)
1157 #define XFS_DQ_BIGTIME_SLACK	((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
1158 
1159 /* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
1160 static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
1161 {
1162 	/*
1163 	 * Round the expiration timestamp up to the nearest bigtime timestamp
1164 	 * that we can store, to give users the most time to fix problems.
1165 	 */
1166 	return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
1167 			XFS_DQ_BIGTIME_SHIFT;
1168 }
1169 
1170 /* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
1171 static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
1172 {
1173 	return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
1174 }
1175 
1176 /*
1177  * Default quota grace periods, ranging from zero (use the compiled defaults)
1178  * to ~136 years.  These are applied to a non-root dquot that has exceeded
1179  * either limit.
1180  */
1181 #define XFS_DQ_GRACE_MIN		((int64_t)0)
1182 #define XFS_DQ_GRACE_MAX		((int64_t)U32_MAX)
1183 
1184 /*
1185  * This is the main portion of the on-disk representation of quota information
1186  * for a user.  We pad this with some more expansion room to construct the on
1187  * disk structure.
1188  */
1189 struct xfs_disk_dquot {
1190 	__be16		d_magic;	/* dquot magic = XFS_DQUOT_MAGIC */
1191 	__u8		d_version;	/* dquot version */
1192 	__u8		d_type;		/* XFS_DQTYPE_USER/PROJ/GROUP */
1193 	__be32		d_id;		/* user,project,group id */
1194 	__be64		d_blk_hardlimit;/* absolute limit on disk blks */
1195 	__be64		d_blk_softlimit;/* preferred limit on disk blks */
1196 	__be64		d_ino_hardlimit;/* maximum # allocated inodes */
1197 	__be64		d_ino_softlimit;/* preferred inode limit */
1198 	__be64		d_bcount;	/* disk blocks owned by the user */
1199 	__be64		d_icount;	/* inodes owned by the user */
1200 	__be32		d_itimer;	/* zero if within inode limits if not,
1201 					   this is when we refuse service */
1202 	__be32		d_btimer;	/* similar to above; for disk blocks */
1203 	__be16		d_iwarns;	/* warnings issued wrt num inodes */
1204 	__be16		d_bwarns;	/* warnings issued wrt disk blocks */
1205 	__be32		d_pad0;		/* 64 bit align */
1206 	__be64		d_rtb_hardlimit;/* absolute limit on realtime blks */
1207 	__be64		d_rtb_softlimit;/* preferred limit on RT disk blks */
1208 	__be64		d_rtbcount;	/* realtime blocks owned */
1209 	__be32		d_rtbtimer;	/* similar to above; for RT disk blocks */
1210 	__be16		d_rtbwarns;	/* warnings issued wrt RT disk blocks */
1211 	__be16		d_pad;
1212 };
1213 
1214 /*
1215  * This is what goes on disk. This is separated from the xfs_disk_dquot because
1216  * carrying the unnecessary padding would be a waste of memory.
1217  */
1218 struct xfs_dqblk {
1219 	struct xfs_disk_dquot	dd_diskdq; /* portion living incore as well */
1220 	char			dd_fill[4];/* filling for posterity */
1221 
1222 	/*
1223 	 * These two are only present on filesystems with the CRC bits set.
1224 	 */
1225 	__be32		  dd_crc;	/* checksum */
1226 	__be64		  dd_lsn;	/* last modification in log */
1227 	uuid_t		  dd_uuid;	/* location information */
1228 };
1229 
1230 #define XFS_DQUOT_CRC_OFF	offsetof(struct xfs_dqblk, dd_crc)
1231 
1232 /*
1233  * This defines the unit of allocation of dquots.
1234  *
1235  * Currently, it is just one file system block, and a 4K blk contains 30
1236  * (136 * 30 = 4080) dquots. It's probably not worth trying to make
1237  * this more dynamic.
1238  *
1239  * However, if this number is changed, we have to make sure that we don't
1240  * implicitly assume that we do allocations in chunks of a single filesystem
1241  * block in the dquot/xqm code.
1242  *
1243  * This is part of the ondisk format because the structure size is not a power
1244  * of two, which leaves slack at the end of the disk block.
1245  */
1246 #define XFS_DQUOT_CLUSTER_SIZE_FSB	(xfs_filblks_t)1
1247 
1248 /*
1249  * Remote symlink format and access functions.
1250  */
1251 #define XFS_SYMLINK_MAGIC	0x58534c4d	/* XSLM */
1252 
1253 struct xfs_dsymlink_hdr {
1254 	__be32	sl_magic;
1255 	__be32	sl_offset;
1256 	__be32	sl_bytes;
1257 	__be32	sl_crc;
1258 	uuid_t	sl_uuid;
1259 	__be64	sl_owner;
1260 	__be64	sl_blkno;
1261 	__be64	sl_lsn;
1262 };
1263 
1264 #define XFS_SYMLINK_CRC_OFF	offsetof(struct xfs_dsymlink_hdr, sl_crc)
1265 
1266 #define XFS_SYMLINK_MAXLEN	1024
1267 /*
1268  * The maximum pathlen is 1024 bytes. Since the minimum file system
1269  * blocksize is 512 bytes, we can get a max of 3 extents back from
1270  * bmapi when crc headers are taken into account.
1271  */
1272 #define XFS_SYMLINK_MAPS 3
1273 
1274 #define XFS_SYMLINK_BUF_SPACE(mp, bufsize)	\
1275 	((bufsize) - (xfs_has_crc((mp)) ? \
1276 			sizeof(struct xfs_dsymlink_hdr) : 0))
1277 
1278 
1279 /*
1280  * Allocation Btree format definitions
1281  *
1282  * There are two on-disk btrees, one sorted by blockno and one sorted
1283  * by blockcount and blockno.  All blocks look the same to make the code
1284  * simpler; if we have time later, we'll make the optimizations.
1285  */
1286 #define	XFS_ABTB_MAGIC		0x41425442	/* 'ABTB' for bno tree */
1287 #define	XFS_ABTB_CRC_MAGIC	0x41423342	/* 'AB3B' */
1288 #define	XFS_ABTC_MAGIC		0x41425443	/* 'ABTC' for cnt tree */
1289 #define	XFS_ABTC_CRC_MAGIC	0x41423343	/* 'AB3C' */
1290 
1291 /*
1292  * Data record/key structure
1293  */
1294 typedef struct xfs_alloc_rec {
1295 	__be32		ar_startblock;	/* starting block number */
1296 	__be32		ar_blockcount;	/* count of free blocks */
1297 } xfs_alloc_rec_t, xfs_alloc_key_t;
1298 
1299 typedef struct xfs_alloc_rec_incore {
1300 	xfs_agblock_t	ar_startblock;	/* starting block number */
1301 	xfs_extlen_t	ar_blockcount;	/* count of free blocks */
1302 } xfs_alloc_rec_incore_t;
1303 
1304 /* btree pointer type */
1305 typedef __be32 xfs_alloc_ptr_t;
1306 
1307 /*
1308  * Block numbers in the AG:
1309  * SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1310  */
1311 #define	XFS_BNO_BLOCK(mp)	((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1312 #define	XFS_CNT_BLOCK(mp)	((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1313 
1314 
1315 /*
1316  * Inode Allocation Btree format definitions
1317  *
1318  * There is a btree for the inode map per allocation group.
1319  */
1320 #define	XFS_IBT_MAGIC		0x49414254	/* 'IABT' */
1321 #define	XFS_IBT_CRC_MAGIC	0x49414233	/* 'IAB3' */
1322 #define	XFS_FIBT_MAGIC		0x46494254	/* 'FIBT' */
1323 #define	XFS_FIBT_CRC_MAGIC	0x46494233	/* 'FIB3' */
1324 
1325 typedef uint64_t	xfs_inofree_t;
1326 #define	XFS_INODES_PER_CHUNK		(NBBY * sizeof(xfs_inofree_t))
1327 #define	XFS_INODES_PER_CHUNK_LOG	(XFS_NBBYLOG + 3)
1328 #define	XFS_INOBT_ALL_FREE		((xfs_inofree_t)-1)
1329 #define	XFS_INOBT_MASK(i)		((xfs_inofree_t)1 << (i))
1330 
1331 #define XFS_INOBT_HOLEMASK_FULL		0	/* holemask for full chunk */
1332 #define XFS_INOBT_HOLEMASK_BITS		(NBBY * sizeof(uint16_t))
1333 #define XFS_INODES_PER_HOLEMASK_BIT	\
1334 	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
1335 
1336 static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1337 {
1338 	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1339 }
1340 
1341 /*
1342  * The on-disk inode record structure has two formats. The original "full"
1343  * format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1344  * and replaces the 3 high-order freecount bytes wth the holemask and inode
1345  * count.
1346  *
1347  * The holemask of the sparse record format allows an inode chunk to have holes
1348  * that refer to blocks not owned by the inode record. This facilitates inode
1349  * allocation in the event of severe free space fragmentation.
1350  */
1351 typedef struct xfs_inobt_rec {
1352 	__be32		ir_startino;	/* starting inode number */
1353 	union {
1354 		struct {
1355 			__be32	ir_freecount;	/* count of free inodes */
1356 		} f;
1357 		struct {
1358 			__be16	ir_holemask;/* hole mask for sparse chunks */
1359 			__u8	ir_count;	/* total inode count */
1360 			__u8	ir_freecount;	/* count of free inodes */
1361 		} sp;
1362 	} ir_u;
1363 	__be64		ir_free;	/* free inode mask */
1364 } xfs_inobt_rec_t;
1365 
1366 typedef struct xfs_inobt_rec_incore {
1367 	xfs_agino_t	ir_startino;	/* starting inode number */
1368 	uint16_t	ir_holemask;	/* hole mask for sparse chunks */
1369 	uint8_t		ir_count;	/* total inode count */
1370 	uint8_t		ir_freecount;	/* count of free inodes (set bits) */
1371 	xfs_inofree_t	ir_free;	/* free inode mask */
1372 } xfs_inobt_rec_incore_t;
1373 
1374 static inline bool xfs_inobt_issparse(uint16_t holemask)
1375 {
1376 	/* non-zero holemask represents a sparse rec. */
1377 	return holemask;
1378 }
1379 
1380 /*
1381  * Key structure
1382  */
1383 typedef struct xfs_inobt_key {
1384 	__be32		ir_startino;	/* starting inode number */
1385 } xfs_inobt_key_t;
1386 
1387 /* btree pointer type */
1388 typedef __be32 xfs_inobt_ptr_t;
1389 
1390 /*
1391  * block numbers in the AG.
1392  */
1393 #define	XFS_IBT_BLOCK(mp)		((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1394 #define	XFS_FIBT_BLOCK(mp)		((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1395 
1396 /*
1397  * Reverse mapping btree format definitions
1398  *
1399  * There is a btree for the reverse map per allocation group
1400  */
1401 #define	XFS_RMAP_CRC_MAGIC	0x524d4233	/* 'RMB3' */
1402 
1403 /*
1404  * Ownership info for an extent.  This is used to create reverse-mapping
1405  * entries.
1406  */
1407 #define XFS_OWNER_INFO_ATTR_FORK	(1 << 0)
1408 #define XFS_OWNER_INFO_BMBT_BLOCK	(1 << 1)
1409 struct xfs_owner_info {
1410 	uint64_t		oi_owner;
1411 	xfs_fileoff_t		oi_offset;
1412 	unsigned int		oi_flags;
1413 };
1414 
1415 /*
1416  * Special owner types.
1417  *
1418  * Seeing as we only support up to 8EB, we have the upper bit of the owner field
1419  * to tell us we have a special owner value. We use these for static metadata
1420  * allocated at mkfs/growfs time, as well as for freespace management metadata.
1421  */
1422 #define XFS_RMAP_OWN_NULL	(-1ULL)	/* No owner, for growfs */
1423 #define XFS_RMAP_OWN_UNKNOWN	(-2ULL)	/* Unknown owner, for EFI recovery */
1424 #define XFS_RMAP_OWN_FS		(-3ULL)	/* static fs metadata */
1425 #define XFS_RMAP_OWN_LOG	(-4ULL)	/* static fs metadata */
1426 #define XFS_RMAP_OWN_AG		(-5ULL)	/* AG freespace btree blocks */
1427 #define XFS_RMAP_OWN_INOBT	(-6ULL)	/* Inode btree blocks */
1428 #define XFS_RMAP_OWN_INODES	(-7ULL)	/* Inode chunk */
1429 #define XFS_RMAP_OWN_REFC	(-8ULL) /* refcount tree */
1430 #define XFS_RMAP_OWN_COW	(-9ULL) /* cow allocations */
1431 #define XFS_RMAP_OWN_MIN	(-10ULL) /* guard */
1432 
1433 #define XFS_RMAP_NON_INODE_OWNER(owner)	(!!((owner) & (1ULL << 63)))
1434 
1435 /*
1436  * Data record structure
1437  */
1438 struct xfs_rmap_rec {
1439 	__be32		rm_startblock;	/* extent start block */
1440 	__be32		rm_blockcount;	/* extent length */
1441 	__be64		rm_owner;	/* extent owner */
1442 	__be64		rm_offset;	/* offset within the owner */
1443 };
1444 
1445 /*
1446  * rmap btree record
1447  *  rm_offset:63 is the attribute fork flag
1448  *  rm_offset:62 is the bmbt block flag
1449  *  rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt)
1450  *  rm_offset:54-60 aren't used and should be zero
1451  *  rm_offset:0-53 is the block offset within the inode
1452  */
1453 #define XFS_RMAP_OFF_ATTR_FORK	((uint64_t)1ULL << 63)
1454 #define XFS_RMAP_OFF_BMBT_BLOCK	((uint64_t)1ULL << 62)
1455 #define XFS_RMAP_OFF_UNWRITTEN	((uint64_t)1ULL << 61)
1456 
1457 #define XFS_RMAP_LEN_MAX	((uint32_t)~0U)
1458 #define XFS_RMAP_OFF_FLAGS	(XFS_RMAP_OFF_ATTR_FORK | \
1459 				 XFS_RMAP_OFF_BMBT_BLOCK | \
1460 				 XFS_RMAP_OFF_UNWRITTEN)
1461 #define XFS_RMAP_OFF_MASK	((uint64_t)0x3FFFFFFFFFFFFFULL)
1462 
1463 #define XFS_RMAP_OFF(off)		((off) & XFS_RMAP_OFF_MASK)
1464 
1465 #define XFS_RMAP_IS_BMBT_BLOCK(off)	(!!((off) & XFS_RMAP_OFF_BMBT_BLOCK))
1466 #define XFS_RMAP_IS_ATTR_FORK(off)	(!!((off) & XFS_RMAP_OFF_ATTR_FORK))
1467 #define XFS_RMAP_IS_UNWRITTEN(len)	(!!((off) & XFS_RMAP_OFF_UNWRITTEN))
1468 
1469 #define RMAPBT_STARTBLOCK_BITLEN	32
1470 #define RMAPBT_BLOCKCOUNT_BITLEN	32
1471 #define RMAPBT_OWNER_BITLEN		64
1472 #define RMAPBT_ATTRFLAG_BITLEN		1
1473 #define RMAPBT_BMBTFLAG_BITLEN		1
1474 #define RMAPBT_EXNTFLAG_BITLEN		1
1475 #define RMAPBT_UNUSED_OFFSET_BITLEN	7
1476 #define RMAPBT_OFFSET_BITLEN		54
1477 
1478 #define XFS_RMAP_ATTR_FORK		(1 << 0)
1479 #define XFS_RMAP_BMBT_BLOCK		(1 << 1)
1480 #define XFS_RMAP_UNWRITTEN		(1 << 2)
1481 #define XFS_RMAP_KEY_FLAGS		(XFS_RMAP_ATTR_FORK | \
1482 					 XFS_RMAP_BMBT_BLOCK)
1483 #define XFS_RMAP_REC_FLAGS		(XFS_RMAP_UNWRITTEN)
1484 struct xfs_rmap_irec {
1485 	xfs_agblock_t	rm_startblock;	/* extent start block */
1486 	xfs_extlen_t	rm_blockcount;	/* extent length */
1487 	uint64_t	rm_owner;	/* extent owner */
1488 	uint64_t	rm_offset;	/* offset within the owner */
1489 	unsigned int	rm_flags;	/* state flags */
1490 };
1491 
1492 /*
1493  * Key structure
1494  *
1495  * We don't use the length for lookups
1496  */
1497 struct xfs_rmap_key {
1498 	__be32		rm_startblock;	/* extent start block */
1499 	__be64		rm_owner;	/* extent owner */
1500 	__be64		rm_offset;	/* offset within the owner */
1501 } __attribute__((packed));
1502 
1503 /* btree pointer type */
1504 typedef __be32 xfs_rmap_ptr_t;
1505 
1506 #define	XFS_RMAP_BLOCK(mp) \
1507 	(xfs_has_finobt(((mp))) ? \
1508 	 XFS_FIBT_BLOCK(mp) + 1 : \
1509 	 XFS_IBT_BLOCK(mp) + 1)
1510 
1511 /*
1512  * Reference Count Btree format definitions
1513  *
1514  */
1515 #define	XFS_REFC_CRC_MAGIC	0x52334643	/* 'R3FC' */
1516 
1517 unsigned int xfs_refc_block(struct xfs_mount *mp);
1518 
1519 /*
1520  * Data record/key structure
1521  *
1522  * Each record associates a range of physical blocks (starting at
1523  * rc_startblock and ending rc_blockcount blocks later) with a reference
1524  * count (rc_refcount).  Extents that are being used to stage a copy on
1525  * write (CoW) operation are recorded in the refcount btree with a
1526  * refcount of 1.  All other records must have a refcount > 1 and must
1527  * track an extent mapped only by file data forks.
1528  *
1529  * Extents with a single owner (attributes, metadata, non-shared file
1530  * data) are not tracked here.  Free space is also not tracked here.
1531  * This is consistent with pre-reflink XFS.
1532  */
1533 
1534 /*
1535  * Extents that are being used to stage a copy on write are stored
1536  * in the refcount btree with a refcount of 1 and the upper bit set
1537  * on the startblock.  This speeds up mount time deletion of stale
1538  * staging extents because they're all at the right side of the tree.
1539  */
1540 #define XFS_REFC_COW_START		((xfs_agblock_t)(1U << 31))
1541 #define REFCNTBT_COWFLAG_BITLEN		1
1542 #define REFCNTBT_AGBLOCK_BITLEN		31
1543 
1544 struct xfs_refcount_rec {
1545 	__be32		rc_startblock;	/* starting block number */
1546 	__be32		rc_blockcount;	/* count of blocks */
1547 	__be32		rc_refcount;	/* number of inodes linked here */
1548 };
1549 
1550 struct xfs_refcount_key {
1551 	__be32		rc_startblock;	/* starting block number */
1552 };
1553 
1554 struct xfs_refcount_irec {
1555 	xfs_agblock_t	rc_startblock;	/* starting block number */
1556 	xfs_extlen_t	rc_blockcount;	/* count of free blocks */
1557 	xfs_nlink_t	rc_refcount;	/* number of inodes linked here */
1558 };
1559 
1560 #define MAXREFCOUNT	((xfs_nlink_t)~0U)
1561 #define MAXREFCEXTLEN	((xfs_extlen_t)~0U)
1562 
1563 /* btree pointer type */
1564 typedef __be32 xfs_refcount_ptr_t;
1565 
1566 
1567 /*
1568  * BMAP Btree format definitions
1569  *
1570  * This includes both the root block definition that sits inside an inode fork
1571  * and the record/pointer formats for the leaf/node in the blocks.
1572  */
1573 #define XFS_BMAP_MAGIC		0x424d4150	/* 'BMAP' */
1574 #define XFS_BMAP_CRC_MAGIC	0x424d4133	/* 'BMA3' */
1575 
1576 /*
1577  * Bmap root header, on-disk form only.
1578  */
1579 typedef struct xfs_bmdr_block {
1580 	__be16		bb_level;	/* 0 is a leaf */
1581 	__be16		bb_numrecs;	/* current # of data records */
1582 } xfs_bmdr_block_t;
1583 
1584 /*
1585  * Bmap btree record and extent descriptor.
1586  *  l0:63 is an extent flag (value 1 indicates non-normal).
1587  *  l0:9-62 are startoff.
1588  *  l0:0-8 and l1:21-63 are startblock.
1589  *  l1:0-20 are blockcount.
1590  */
1591 #define BMBT_EXNTFLAG_BITLEN	1
1592 #define BMBT_STARTOFF_BITLEN	54
1593 #define BMBT_STARTBLOCK_BITLEN	52
1594 #define BMBT_BLOCKCOUNT_BITLEN	21
1595 
1596 #define BMBT_STARTOFF_MASK	((1ULL << BMBT_STARTOFF_BITLEN) - 1)
1597 #define BMBT_BLOCKCOUNT_MASK	((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
1598 
1599 /*
1600  * bmbt records have a file offset (block) field that is 54 bits wide, so this
1601  * is the largest xfs_fileoff_t that we ever expect to see.
1602  */
1603 #define XFS_MAX_FILEOFF		(BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
1604 
1605 typedef struct xfs_bmbt_rec {
1606 	__be64			l0, l1;
1607 } xfs_bmbt_rec_t;
1608 
1609 typedef uint64_t	xfs_bmbt_rec_base_t;	/* use this for casts */
1610 typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1611 
1612 /*
1613  * Values and macros for delayed-allocation startblock fields.
1614  */
1615 #define STARTBLOCKVALBITS	17
1616 #define STARTBLOCKMASKBITS	(15 + 20)
1617 #define STARTBLOCKMASK		\
1618 	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1619 
1620 static inline int isnullstartblock(xfs_fsblock_t x)
1621 {
1622 	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1623 }
1624 
1625 static inline xfs_fsblock_t nullstartblock(int k)
1626 {
1627 	ASSERT(k < (1 << STARTBLOCKVALBITS));
1628 	return STARTBLOCKMASK | (k);
1629 }
1630 
1631 static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1632 {
1633 	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1634 }
1635 
1636 /*
1637  * Key structure for non-leaf levels of the tree.
1638  */
1639 typedef struct xfs_bmbt_key {
1640 	__be64		br_startoff;	/* starting file offset */
1641 } xfs_bmbt_key_t, xfs_bmdr_key_t;
1642 
1643 /* btree pointer type */
1644 typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1645 
1646 
1647 /*
1648  * Generic Btree block format definitions
1649  *
1650  * This is a combination of the actual format used on disk for short and long
1651  * format btrees.  The first three fields are shared by both format, but the
1652  * pointers are different and should be used with care.
1653  *
1654  * To get the size of the actual short or long form headers please use the size
1655  * macros below.  Never use sizeof(xfs_btree_block).
1656  *
1657  * The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1658  * with the crc feature bit, and all accesses to them must be conditional on
1659  * that flag.
1660  */
1661 /* short form block header */
1662 struct xfs_btree_block_shdr {
1663 	__be32		bb_leftsib;
1664 	__be32		bb_rightsib;
1665 
1666 	__be64		bb_blkno;
1667 	__be64		bb_lsn;
1668 	uuid_t		bb_uuid;
1669 	__be32		bb_owner;
1670 	__le32		bb_crc;
1671 };
1672 
1673 /* long form block header */
1674 struct xfs_btree_block_lhdr {
1675 	__be64		bb_leftsib;
1676 	__be64		bb_rightsib;
1677 
1678 	__be64		bb_blkno;
1679 	__be64		bb_lsn;
1680 	uuid_t		bb_uuid;
1681 	__be64		bb_owner;
1682 	__le32		bb_crc;
1683 	__be32		bb_pad; /* padding for alignment */
1684 };
1685 
1686 struct xfs_btree_block {
1687 	__be32		bb_magic;	/* magic number for block type */
1688 	__be16		bb_level;	/* 0 is a leaf */
1689 	__be16		bb_numrecs;	/* current # of data records */
1690 	union {
1691 		struct xfs_btree_block_shdr s;
1692 		struct xfs_btree_block_lhdr l;
1693 	} bb_u;				/* rest */
1694 };
1695 
1696 /* size of a short form block */
1697 #define XFS_BTREE_SBLOCK_LEN \
1698 	(offsetof(struct xfs_btree_block, bb_u) + \
1699 	 offsetof(struct xfs_btree_block_shdr, bb_blkno))
1700 /* size of a long form block */
1701 #define XFS_BTREE_LBLOCK_LEN \
1702 	(offsetof(struct xfs_btree_block, bb_u) + \
1703 	 offsetof(struct xfs_btree_block_lhdr, bb_blkno))
1704 
1705 /* sizes of CRC enabled btree blocks */
1706 #define XFS_BTREE_SBLOCK_CRC_LEN \
1707 	(offsetof(struct xfs_btree_block, bb_u) + \
1708 	 sizeof(struct xfs_btree_block_shdr))
1709 #define XFS_BTREE_LBLOCK_CRC_LEN \
1710 	(offsetof(struct xfs_btree_block, bb_u) + \
1711 	 sizeof(struct xfs_btree_block_lhdr))
1712 
1713 #define XFS_BTREE_SBLOCK_CRC_OFF \
1714 	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1715 #define XFS_BTREE_LBLOCK_CRC_OFF \
1716 	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1717 
1718 /*
1719  * On-disk XFS access control list structure.
1720  */
1721 struct xfs_acl_entry {
1722 	__be32	ae_tag;
1723 	__be32	ae_id;
1724 	__be16	ae_perm;
1725 	__be16	ae_pad;		/* fill the implicit hole in the structure */
1726 };
1727 
1728 struct xfs_acl {
1729 	__be32			acl_cnt;
1730 	struct xfs_acl_entry	acl_entry[];
1731 };
1732 
1733 /*
1734  * The number of ACL entries allowed is defined by the on-disk format.
1735  * For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
1736  * limited only by the maximum size of the xattr that stores the information.
1737  */
1738 #define XFS_ACL_MAX_ENTRIES(mp)	\
1739 	(xfs_has_crc(mp) \
1740 		?  (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
1741 						sizeof(struct xfs_acl_entry) \
1742 		: 25)
1743 
1744 #define XFS_ACL_SIZE(cnt) \
1745 	(sizeof(struct xfs_acl) + \
1746 		sizeof(struct xfs_acl_entry) * cnt)
1747 
1748 #define XFS_ACL_MAX_SIZE(mp) \
1749 	XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
1750 
1751 
1752 /* On-disk XFS extended attribute names */
1753 #define SGI_ACL_FILE		"SGI_ACL_FILE"
1754 #define SGI_ACL_DEFAULT		"SGI_ACL_DEFAULT"
1755 #define SGI_ACL_FILE_SIZE	(sizeof(SGI_ACL_FILE)-1)
1756 #define SGI_ACL_DEFAULT_SIZE	(sizeof(SGI_ACL_DEFAULT)-1)
1757 
1758 #endif /* __XFS_FORMAT_H__ */
1759