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 be padded to 64 bit alignment.
94	*/
95	typedef struct xfs_sb {
96	uint32_t sb_magicnum; /* magic number == XFS_SB_MAGIC */
97	uint32_t sb_blocksize; /* logical block size, bytes */
98	xfs_rfsblock_t sb_dblocks; /* number of data blocks */
99	xfs_rfsblock_t sb_rblocks; /* number of realtime blocks */
100	xfs_rtbxlen_t sb_rextents; /* number of realtime extents */
101	uuid_t sb_uuid; /* user-visible file system unique id */
102	xfs_fsblock_t sb_logstart; /* starting block of log if internal */
103	xfs_ino_t sb_rootino; /* root inode number */
104	xfs_ino_t sb_rbmino; /* bitmap inode for realtime extents */
105	xfs_ino_t sb_rsumino; /* summary inode for rt bitmap */
106	xfs_agblock_t sb_rextsize; /* realtime extent size, blocks */
107	xfs_agblock_t sb_agblocks; /* size of an allocation group */
108	xfs_agnumber_t sb_agcount; /* number of allocation groups */
109	xfs_extlen_t sb_rbmblocks; /* number of rt bitmap blocks */
110	xfs_extlen_t sb_logblocks; /* number of log blocks */
111	uint16_t sb_versionnum; /* header version == XFS_SB_VERSION */
112	uint16_t sb_sectsize; /* volume sector size, bytes */
113	uint16_t sb_inodesize; /* inode size, bytes */
114	uint16_t sb_inopblock; /* inodes per block */
115	char sb_fname[XFSLABEL_MAX] __nonstring; /* file system name */
116	uint8_t sb_blocklog; /* log2 of sb_blocksize */
117	uint8_t sb_sectlog; /* log2 of sb_sectsize */
118	uint8_t sb_inodelog; /* log2 of sb_inodesize */
119	uint8_t sb_inopblog; /* log2 of sb_inopblock */
120	uint8_t sb_agblklog; /* log2 of sb_agblocks (rounded up) */
121	uint8_t sb_rextslog; /* log2 of sb_rextents */
122	uint8_t sb_inprogress; /* mkfs is in progress, don't mount */
123	uint8_t sb_imax_pct; /* max % of fs for inode space */
124	/* statistics */
125	/*
126	* These fields must remain contiguous. If you really
127	* want to change their layout, make sure you fix the
128	* code in xfs_trans_apply_sb_deltas().
129	*/
130	uint64_t sb_icount; /* allocated inodes */
131	uint64_t sb_ifree; /* free inodes */
132	uint64_t sb_fdblocks; /* free data blocks */
133	uint64_t sb_frextents; /* free realtime extents */
134	/*
135	* End contiguous fields.
136	*/
137	xfs_ino_t sb_uquotino; /* user quota inode */
138	xfs_ino_t sb_gquotino; /* group quota inode */
139	uint16_t sb_qflags; /* quota flags */
140	uint8_t sb_flags; /* misc. flags */
141	uint8_t sb_shared_vn; /* shared version number */
142	xfs_extlen_t sb_inoalignmt; /* inode chunk alignment, fsblocks */
143	uint32_t sb_unit; /* stripe or raid unit */
144	uint32_t sb_width; /* stripe or raid width */
145	uint8_t sb_dirblklog; /* log2 of dir block size (fsbs) */
146	uint8_t sb_logsectlog; /* log2 of the log sector size */
147	uint16_t sb_logsectsize; /* sector size for the log, bytes */
148	uint32_t sb_logsunit; /* stripe unit size for the log */
149	uint32_t sb_features2; /* additional feature bits */
150
151	/*
152	* bad features2 field as a result of failing to pad the sb structure to
153	* 64 bits. Some machines will be using this field for features2 bits.
154	* Easiest just to mark it bad and not use it for anything else.
155	*
156	* This is not kept up to date in memory; it is always overwritten by
157	* the value in sb_features2 when formatting the incore superblock to
158	* the disk buffer.
159	*/
160	uint32_t sb_bad_features2;
161
162	/* version 5 superblock fields start here */
163
164	/* feature masks */
165	uint32_t sb_features_compat;
166	uint32_t sb_features_ro_compat;
167	uint32_t sb_features_incompat;
168	uint32_t sb_features_log_incompat;
169
170	uint32_t sb_crc; /* superblock crc */
171	xfs_extlen_t sb_spino_align; /* sparse inode chunk alignment */
172
173	xfs_ino_t sb_pquotino; /* project quota inode */
174	xfs_lsn_t sb_lsn; /* last write sequence */
175	uuid_t sb_meta_uuid; /* metadata file system unique id */
176
177	xfs_ino_t sb_metadirino; /* metadata directory tree root */
178
179	xfs_rgnumber_t sb_rgcount; /* number of realtime groups */
180	xfs_rtxlen_t sb_rgextents; /* size of a realtime group in rtx */
181	uint8_t sb_rgblklog; /* rt group number shift */
182	uint8_t sb_pad[7]; /* zeroes */
183	xfs_rfsblock_t sb_rtstart; /* start of internal RT section (FSB) */
184	xfs_filblks_t sb_rtreserved; /* reserved (zoned) RT blocks */
185
186	/* must be padded to 64 bit alignment */
187	} xfs_sb_t;
188
189	/*
190	* Superblock - on disk version.
191	* Must be padded to 64 bit alignment.
192	*/
193	struct xfs_dsb {
194	__be32 sb_magicnum; /* magic number == XFS_SB_MAGIC */
195	__be32 sb_blocksize; /* logical block size, bytes */
196	__be64 sb_dblocks; /* number of data blocks */
197	__be64 sb_rblocks; /* number of realtime blocks */
198	__be64 sb_rextents; /* number of realtime extents */
199	uuid_t sb_uuid; /* user-visible file system unique id */
200	__be64 sb_logstart; /* starting block of log if internal */
201	__be64 sb_rootino; /* root inode number */
202	__be64 sb_rbmino; /* bitmap inode for realtime extents */
203	__be64 sb_rsumino; /* summary inode for rt bitmap */
204	__be32 sb_rextsize; /* realtime extent size, blocks */
205	__be32 sb_agblocks; /* size of an allocation group */
206	__be32 sb_agcount; /* number of allocation groups */
207	__be32 sb_rbmblocks; /* number of rt bitmap blocks */
208	__be32 sb_logblocks; /* number of log blocks */
209	__be16 sb_versionnum; /* header version == XFS_SB_VERSION */
210	__be16 sb_sectsize; /* volume sector size, bytes */
211	__be16 sb_inodesize; /* inode size, bytes */
212	__be16 sb_inopblock; /* inodes per block */
213	char sb_fname[XFSLABEL_MAX]; /* file system name */
214	__u8 sb_blocklog; /* log2 of sb_blocksize */
215	__u8 sb_sectlog; /* log2 of sb_sectsize */
216	__u8 sb_inodelog; /* log2 of sb_inodesize */
217	__u8 sb_inopblog; /* log2 of sb_inopblock */
218	__u8 sb_agblklog; /* log2 of sb_agblocks (rounded up) */
219	__u8 sb_rextslog; /* log2 of sb_rextents */
220	__u8 sb_inprogress; /* mkfs is in progress, don't mount */
221	__u8 sb_imax_pct; /* max % of fs for inode space */
222	/* statistics */
223	/*
224	* These fields must remain contiguous. If you really
225	* want to change their layout, make sure you fix the
226	* code in xfs_trans_apply_sb_deltas().
227	*/
228	__be64 sb_icount; /* allocated inodes */
229	__be64 sb_ifree; /* free inodes */
230	__be64 sb_fdblocks; /* free data blocks */
231	__be64 sb_frextents; /* free realtime extents */
232	/*
233	* End contiguous fields.
234	*/
235	__be64 sb_uquotino; /* user quota inode */
236	__be64 sb_gquotino; /* group quota inode */
237	__be16 sb_qflags; /* quota flags */
238	__u8 sb_flags; /* misc. flags */
239	__u8 sb_shared_vn; /* shared version number */
240	__be32 sb_inoalignmt; /* inode chunk alignment, fsblocks */
241	__be32 sb_unit; /* stripe or raid unit */
242	__be32 sb_width; /* stripe or raid width */
243	__u8 sb_dirblklog; /* log2 of dir block size (fsbs) */
244	__u8 sb_logsectlog; /* log2 of the log sector size */
245	__be16 sb_logsectsize; /* sector size for the log, bytes */
246	__be32 sb_logsunit; /* stripe unit size for the log */
247	__be32 sb_features2; /* additional feature bits */
248	/*
249	* bad features2 field as a result of failing to pad the sb
250	* structure to 64 bits. Some machines will be using this field
251	* for features2 bits. Easiest just to mark it bad and not use
252	* it for anything else.
253	*/
254	__be32 sb_bad_features2;
255
256	/* version 5 superblock fields start here */
257
258	/* feature masks */
259	__be32 sb_features_compat;
260	__be32 sb_features_ro_compat;
261	__be32 sb_features_incompat;
262	__be32 sb_features_log_incompat;
263
264	__le32 sb_crc; /* superblock crc */
265	__be32 sb_spino_align; /* sparse inode chunk alignment */
266
267	__be64 sb_pquotino; /* project quota inode */
268	__be64 sb_lsn; /* last write sequence */
269	uuid_t sb_meta_uuid; /* metadata file system unique id */
270
271	__be64 sb_metadirino; /* metadata directory tree root */
272	__be32 sb_rgcount; /* # of realtime groups */
273	__be32 sb_rgextents; /* size of rtgroup in rtx */
274	__u8 sb_rgblklog; /* rt group number shift */
275	__u8 sb_pad[7]; /* zeroes */
276	__be64 sb_rtstart; /* start of internal RT section (FSB) */
277	__be64 sb_rtreserved; /* reserved (zoned) RT blocks */
278
279	/*
280	* The size of this structure must be padded to 64 bit alignment.
281	*
282	* NOTE: Don't forget to update secondary_sb_whack in xfs_repair when
283	* adding new fields here.
284	*/
285	};
286
287	#define XFS_SB_CRC_OFF offsetof(struct xfs_dsb, sb_crc)
288
289	/*
290	* Misc. Flags - warning - these will be cleared by xfs_repair unless
291	* a feature bit is set when the flag is used.
292	*/
293	#define XFS_SBF_NOFLAGS 0x00 /* no flags set */
294	#define XFS_SBF_READONLY 0x01 /* only read-only mounts allowed */
295
296	/*
297	* define max. shared version we can interoperate with
298	*/
299	#define XFS_SB_MAX_SHARED_VN 0
300
301	#define XFS_SB_VERSION_NUM(sbp) ((sbp)->sb_versionnum & XFS_SB_VERSION_NUMBITS)
302
303	static inline bool xfs_sb_is_v5(const struct xfs_sb *sbp)
304	{
305	return XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5;
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(const struct xfs_sb *sbp)
313	{
314	return sbp->sb_bad_features2 != sbp->sb_features2;
315	}
316
317	static inline bool xfs_sb_version_hasmorebits(const struct xfs_sb *sbp)
318	{
319	return xfs_sb_is_v5(sbp) ||
320	(sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT);
321	}
322
323	static inline void xfs_sb_version_addattr(struct xfs_sb *sbp)
324	{
325	sbp->sb_versionnum |= XFS_SB_VERSION_ATTRBIT;
326	}
327
328	static inline void xfs_sb_version_addquota(struct xfs_sb *sbp)
329	{
330	sbp->sb_versionnum |= XFS_SB_VERSION_QUOTABIT;
331	}
332
333	static inline void xfs_sb_version_addattr2(struct xfs_sb *sbp)
334	{
335	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
336	sbp->sb_features2 |= XFS_SB_VERSION2_ATTR2BIT;
337	}
338
339	static inline void xfs_sb_version_addprojid32(struct xfs_sb *sbp)
340	{
341	sbp->sb_versionnum |= XFS_SB_VERSION_MOREBITSBIT;
342	sbp->sb_features2 |= XFS_SB_VERSION2_PROJID32BIT;
343	}
344
345	/*
346	* Extended v5 superblock feature masks. These are to be used for new v5
347	* superblock features only.
348	*
349	* Compat features are new features that old kernels will not notice or affect
350	* and so can mount read-write without issues.
351	*
352	* RO-Compat (read only) are features that old kernels can read but will break
353	* if they write. Hence only read-only mounts of such filesystems are allowed on
354	* kernels that don't support the feature bit.
355	*
356	* InCompat features are features which old kernels will not understand and so
357	* must not mount.
358	*
359	* Log-InCompat features are for changes to log formats or new transactions that
360	* can't be replayed on older kernels. The fields are set when the filesystem is
361	* mounted, and a clean unmount clears the fields.
362	*/
363	#define XFS_SB_FEAT_COMPAT_ALL 0
364	#define XFS_SB_FEAT_COMPAT_UNKNOWN ~XFS_SB_FEAT_COMPAT_ALL
365	static inline bool
366	xfs_sb_has_compat_feature(
367	const struct xfs_sb *sbp,
368	uint32_t feature)
369	{
370	return (sbp->sb_features_compat & feature) != 0;
371	}
372
373	#define XFS_SB_FEAT_RO_COMPAT_FINOBT (1 << 0) /* free inode btree */
374	#define XFS_SB_FEAT_RO_COMPAT_RMAPBT (1 << 1) /* reverse map btree */
375	#define XFS_SB_FEAT_RO_COMPAT_REFLINK (1 << 2) /* reflinked files */
376	#define XFS_SB_FEAT_RO_COMPAT_INOBTCNT (1 << 3) /* inobt block counts */
377	#define XFS_SB_FEAT_RO_COMPAT_ALL \
378	(XFS_SB_FEAT_RO_COMPAT_FINOBT | \
379	XFS_SB_FEAT_RO_COMPAT_RMAPBT | \
380	XFS_SB_FEAT_RO_COMPAT_REFLINK| \
381	XFS_SB_FEAT_RO_COMPAT_INOBTCNT)
382	#define XFS_SB_FEAT_RO_COMPAT_UNKNOWN ~XFS_SB_FEAT_RO_COMPAT_ALL
383	static inline bool
384	xfs_sb_has_ro_compat_feature(
385	const struct xfs_sb *sbp,
386	uint32_t feature)
387	{
388	return (sbp->sb_features_ro_compat & feature) != 0;
389	}
390
391	#define XFS_SB_FEAT_INCOMPAT_FTYPE (1 << 0) /* filetype in dirent */
392	#define XFS_SB_FEAT_INCOMPAT_SPINODES (1 << 1) /* sparse inode chunks */
393	#define XFS_SB_FEAT_INCOMPAT_META_UUID (1 << 2) /* metadata UUID */
394	#define XFS_SB_FEAT_INCOMPAT_BIGTIME (1 << 3) /* large timestamps */
395	#define XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR (1 << 4) /* needs xfs_repair */
396	#define XFS_SB_FEAT_INCOMPAT_NREXT64 (1 << 5) /* large extent counters */
397	#define XFS_SB_FEAT_INCOMPAT_EXCHRANGE (1 << 6) /* exchangerange supported */
398	#define XFS_SB_FEAT_INCOMPAT_PARENT (1 << 7) /* parent pointers */
399	#define XFS_SB_FEAT_INCOMPAT_METADIR (1 << 8) /* metadata dir tree */
400	#define XFS_SB_FEAT_INCOMPAT_ZONED (1 << 9) /* zoned RT allocator */
401	#define XFS_SB_FEAT_INCOMPAT_ZONE_GAPS (1 << 10) /* RTGs have LBA gaps */
402
403	#define XFS_SB_FEAT_INCOMPAT_ALL \
404	(XFS_SB_FEAT_INCOMPAT_FTYPE | \
405	XFS_SB_FEAT_INCOMPAT_SPINODES | \
406	XFS_SB_FEAT_INCOMPAT_META_UUID | \
407	XFS_SB_FEAT_INCOMPAT_BIGTIME | \
408	XFS_SB_FEAT_INCOMPAT_NEEDSREPAIR | \
409	XFS_SB_FEAT_INCOMPAT_NREXT64 | \
410	XFS_SB_FEAT_INCOMPAT_EXCHRANGE | \
411	XFS_SB_FEAT_INCOMPAT_PARENT | \
412	XFS_SB_FEAT_INCOMPAT_METADIR | \
413	XFS_SB_FEAT_INCOMPAT_ZONED | \
414	XFS_SB_FEAT_INCOMPAT_ZONE_GAPS)
415
416	#define XFS_SB_FEAT_INCOMPAT_UNKNOWN ~XFS_SB_FEAT_INCOMPAT_ALL
417	static inline bool
418	xfs_sb_has_incompat_feature(
419	const struct xfs_sb *sbp,
420	uint32_t feature)
421	{
422	return (sbp->sb_features_incompat & feature) != 0;
423	}
424
425	#define XFS_SB_FEAT_INCOMPAT_LOG_XATTRS (1 << 0) /* Delayed Attributes */
426	#define XFS_SB_FEAT_INCOMPAT_LOG_ALL \
427	(XFS_SB_FEAT_INCOMPAT_LOG_XATTRS)
428	#define XFS_SB_FEAT_INCOMPAT_LOG_UNKNOWN ~XFS_SB_FEAT_INCOMPAT_LOG_ALL
429	static inline bool
430	xfs_sb_has_incompat_log_feature(
431	const struct xfs_sb *sbp,
432	uint32_t feature)
433	{
434	return (sbp->sb_features_log_incompat & feature) != 0;
435	}
436
437	static inline void
438	xfs_sb_remove_incompat_log_features(
439	struct xfs_sb *sbp)
440	{
441	sbp->sb_features_log_incompat &= ~XFS_SB_FEAT_INCOMPAT_LOG_ALL;
442	}
443
444	static inline void
445	xfs_sb_add_incompat_log_features(
446	struct xfs_sb *sbp,
447	unsigned int features)
448	{
449	sbp->sb_features_log_incompat |= features;
450	}
451
452	static inline bool xfs_sb_version_haslogxattrs(const struct xfs_sb *sbp)
453	{
454	return xfs_sb_is_v5(sbp) && (sbp->sb_features_log_incompat &
455	XFS_SB_FEAT_INCOMPAT_LOG_XATTRS);
456	}
457
458	static inline bool
459	xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
460	{
461	return (ino == sbp->sb_uquotino ||
462	ino == sbp->sb_gquotino ||
463	ino == sbp->sb_pquotino);
464	}
465
466	#define XFS_SB_DADDR ((xfs_daddr_t)0) /* daddr in filesystem/ag */
467	#define XFS_SB_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_SB_DADDR)
468
469	#define XFS_HDR_BLOCK(mp,d) ((xfs_agblock_t)XFS_BB_TO_FSBT(mp,d))
470	#define XFS_DADDR_TO_FSB(mp,d) XFS_AGB_TO_FSB(mp, \
471	xfs_daddr_to_agno(mp,d), xfs_daddr_to_agbno(mp,d))
472	#define XFS_FSB_TO_DADDR(mp,fsbno) XFS_AGB_TO_DADDR(mp, \
473	XFS_FSB_TO_AGNO(mp,fsbno), XFS_FSB_TO_AGBNO(mp,fsbno))
474
475	/*
476	* File system sector to basic block conversions.
477	*/
478	#define XFS_FSS_TO_BB(mp,sec) ((sec) << (mp)->m_sectbb_log)
479
480	/*
481	* File system block to basic block conversions.
482	*/
483	#define XFS_FSB_TO_BB(mp,fsbno) ((fsbno) << (mp)->m_blkbb_log)
484	#define XFS_BB_TO_FSB(mp,bb) \
485	(((bb) + (XFS_FSB_TO_BB(mp,1) - 1)) >> (mp)->m_blkbb_log)
486	#define XFS_BB_TO_FSBT(mp,bb) ((bb) >> (mp)->m_blkbb_log)
487
488	/*
489	* File system block to byte conversions.
490	*/
491	#define XFS_FSB_TO_B(mp,fsbno) ((xfs_fsize_t)(fsbno) << (mp)->m_sb.sb_blocklog)
492	#define XFS_B_TO_FSB(mp,b) \
493	((((uint64_t)(b)) + (mp)->m_blockmask) >> (mp)->m_sb.sb_blocklog)
494	#define XFS_B_TO_FSBT(mp,b) (((uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
495
496	/*
497	* Allocation group header
498	*
499	* This is divided into three structures, placed in sequential 512-byte
500	* buffers after a copy of the superblock (also in a 512-byte buffer).
501	*/
502	#define XFS_AGF_MAGIC 0x58414746 /* 'XAGF' */
503	#define XFS_AGI_MAGIC 0x58414749 /* 'XAGI' */
504	#define XFS_AGFL_MAGIC 0x5841464c /* 'XAFL' */
505	#define XFS_AGF_VERSION 1
506	#define XFS_AGI_VERSION 1
507
508	#define XFS_AGF_GOOD_VERSION(v) ((v) == XFS_AGF_VERSION)
509	#define XFS_AGI_GOOD_VERSION(v) ((v) == XFS_AGI_VERSION)
510
511	/*
512	* agf_cnt_level in the first AGF overlaps the EFS superblock's magic number.
513	* Since the magic numbers valid for EFS are > 64k, our value cannot be confused
514	* for an EFS superblock.
515	*/
516
517	typedef struct xfs_agf {
518	/*
519	* Common allocation group header information
520	*/
521	__be32 agf_magicnum; /* magic number == XFS_AGF_MAGIC */
522	__be32 agf_versionnum; /* header version == XFS_AGF_VERSION */
523	__be32 agf_seqno; /* sequence # starting from 0 */
524	__be32 agf_length; /* size in blocks of a.g. */
525	/*
526	* Freespace and rmap information
527	*/
528	__be32 agf_bno_root; /* bnobt root block */
529	__be32 agf_cnt_root; /* cntbt root block */
530	__be32 agf_rmap_root; /* rmapbt root block */
531
532	__be32 agf_bno_level; /* bnobt btree levels */
533	__be32 agf_cnt_level; /* cntbt btree levels */
534	__be32 agf_rmap_level; /* rmapbt btree levels */
535
536	__be32 agf_flfirst; /* first freelist block's index */
537	__be32 agf_fllast; /* last freelist block's index */
538	__be32 agf_flcount; /* count of blocks in freelist */
539	__be32 agf_freeblks; /* total free blocks */
540
541	__be32 agf_longest; /* longest free space */
542	__be32 agf_btreeblks; /* # of blocks held in AGF btrees */
543	uuid_t agf_uuid; /* uuid of filesystem */
544
545	__be32 agf_rmap_blocks; /* rmapbt blocks used */
546	__be32 agf_refcount_blocks; /* refcountbt blocks used */
547
548	__be32 agf_refcount_root; /* refcount tree root block */
549	__be32 agf_refcount_level; /* refcount btree levels */
550
551	/*
552	* reserve some contiguous space for future logged fields before we add
553	* the unlogged fields. This makes the range logging via flags and
554	* structure offsets much simpler.
555	*/
556	__be64 agf_spare64[14];
557
558	/* unlogged fields, written during buffer writeback. */
559	__be64 agf_lsn; /* last write sequence */
560	__be32 agf_crc; /* crc of agf sector */
561	__be32 agf_spare2;
562
563	/* structure must be padded to 64 bit alignment */
564	} xfs_agf_t;
565
566	#define XFS_AGF_CRC_OFF offsetof(struct xfs_agf, agf_crc)
567
568	#define XFS_AGF_MAGICNUM (1u << 0)
569	#define XFS_AGF_VERSIONNUM (1u << 1)
570	#define XFS_AGF_SEQNO (1u << 2)
571	#define XFS_AGF_LENGTH (1u << 3)
572	#define XFS_AGF_ROOTS (1u << 4)
573	#define XFS_AGF_LEVELS (1u << 5)
574	#define XFS_AGF_FLFIRST (1u << 6)
575	#define XFS_AGF_FLLAST (1u << 7)
576	#define XFS_AGF_FLCOUNT (1u << 8)
577	#define XFS_AGF_FREEBLKS (1u << 9)
578	#define XFS_AGF_LONGEST (1u << 10)
579	#define XFS_AGF_BTREEBLKS (1u << 11)
580	#define XFS_AGF_UUID (1u << 12)
581	#define XFS_AGF_RMAP_BLOCKS (1u << 13)
582	#define XFS_AGF_REFCOUNT_BLOCKS (1u << 14)
583	#define XFS_AGF_REFCOUNT_ROOT (1u << 15)
584	#define XFS_AGF_REFCOUNT_LEVEL (1u << 16)
585	#define XFS_AGF_SPARE64 (1u << 17)
586	#define XFS_AGF_NUM_BITS 18
587	#define XFS_AGF_ALL_BITS ((1u << XFS_AGF_NUM_BITS) - 1)
588
589	#define XFS_AGF_FLAGS \
590	{ XFS_AGF_MAGICNUM, "MAGICNUM" }, \
591	{ XFS_AGF_VERSIONNUM, "VERSIONNUM" }, \
592	{ XFS_AGF_SEQNO, "SEQNO" }, \
593	{ XFS_AGF_LENGTH, "LENGTH" }, \
594	{ XFS_AGF_ROOTS, "ROOTS" }, \
595	{ XFS_AGF_LEVELS, "LEVELS" }, \
596	{ XFS_AGF_FLFIRST, "FLFIRST" }, \
597	{ XFS_AGF_FLLAST, "FLLAST" }, \
598	{ XFS_AGF_FLCOUNT, "FLCOUNT" }, \
599	{ XFS_AGF_FREEBLKS, "FREEBLKS" }, \
600	{ XFS_AGF_LONGEST, "LONGEST" }, \
601	{ XFS_AGF_BTREEBLKS, "BTREEBLKS" }, \
602	{ XFS_AGF_UUID, "UUID" }, \
603	{ XFS_AGF_RMAP_BLOCKS, "RMAP_BLOCKS" }, \
604	{ XFS_AGF_REFCOUNT_BLOCKS, "REFCOUNT_BLOCKS" }, \
605	{ XFS_AGF_REFCOUNT_ROOT, "REFCOUNT_ROOT" }, \
606	{ XFS_AGF_REFCOUNT_LEVEL, "REFCOUNT_LEVEL" }, \
607	{ XFS_AGF_SPARE64, "SPARE64" }
608
609	/* disk block (xfs_daddr_t) in the AG */
610	#define XFS_AGF_DADDR(mp) ((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
611	#define XFS_AGF_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
612
613	/*
614	* Size of the unlinked inode hash table in the agi.
615	*/
616	#define XFS_AGI_UNLINKED_BUCKETS 64
617
618	typedef struct xfs_agi {
619	/*
620	* Common allocation group header information
621	*/
622	__be32 agi_magicnum; /* magic number == XFS_AGI_MAGIC */
623	__be32 agi_versionnum; /* header version == XFS_AGI_VERSION */
624	__be32 agi_seqno; /* sequence # starting from 0 */
625	__be32 agi_length; /* size in blocks of a.g. */
626	/*
627	* Inode information
628	* Inodes are mapped by interpreting the inode number, so no
629	* mapping data is needed here.
630	*/
631	__be32 agi_count; /* count of allocated inodes */
632	__be32 agi_root; /* root of inode btree */
633	__be32 agi_level; /* levels in inode btree */
634	__be32 agi_freecount; /* number of free inodes */
635
636	__be32 agi_newino; /* new inode just allocated */
637	__be32 agi_dirino; /* last directory inode chunk */
638	/*
639	* Hash table of inodes which have been unlinked but are
640	* still being referenced.
641	*/
642	__be32 agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
643	/*
644	* This marks the end of logging region 1 and start of logging region 2.
645	*/
646	uuid_t agi_uuid; /* uuid of filesystem */
647	__be32 agi_crc; /* crc of agi sector */
648	__be32 agi_pad32;
649	__be64 agi_lsn; /* last write sequence */
650
651	__be32 agi_free_root; /* root of the free inode btree */
652	__be32 agi_free_level;/* levels in free inode btree */
653
654	__be32 agi_iblocks; /* inobt blocks used */
655	__be32 agi_fblocks; /* finobt blocks used */
656
657	/* structure must be padded to 64 bit alignment */
658	} xfs_agi_t;
659
660	#define XFS_AGI_CRC_OFF offsetof(struct xfs_agi, agi_crc)
661
662	#define XFS_AGI_MAGICNUM (1u << 0)
663	#define XFS_AGI_VERSIONNUM (1u << 1)
664	#define XFS_AGI_SEQNO (1u << 2)
665	#define XFS_AGI_LENGTH (1u << 3)
666	#define XFS_AGI_COUNT (1u << 4)
667	#define XFS_AGI_ROOT (1u << 5)
668	#define XFS_AGI_LEVEL (1u << 6)
669	#define XFS_AGI_FREECOUNT (1u << 7)
670	#define XFS_AGI_NEWINO (1u << 8)
671	#define XFS_AGI_DIRINO (1u << 9)
672	#define XFS_AGI_UNLINKED (1u << 10)
673	#define XFS_AGI_NUM_BITS_R1 11 /* end of the 1st agi logging region */
674	#define XFS_AGI_ALL_BITS_R1 ((1u << XFS_AGI_NUM_BITS_R1) - 1)
675	#define XFS_AGI_FREE_ROOT (1u << 11)
676	#define XFS_AGI_FREE_LEVEL (1u << 12)
677	#define XFS_AGI_IBLOCKS (1u << 13) /* both inobt/finobt block counters */
678	#define XFS_AGI_NUM_BITS_R2 14
679
680	/* disk block (xfs_daddr_t) in the AG */
681	#define XFS_AGI_DADDR(mp) ((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
682	#define XFS_AGI_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
683
684	/*
685	* The third a.g. block contains the a.g. freelist, an array
686	* of block pointers to blocks owned by the allocation btree code.
687	*/
688	#define XFS_AGFL_DADDR(mp) ((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
689	#define XFS_AGFL_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
690	#define XFS_BUF_TO_AGFL(bp) ((struct xfs_agfl *)((bp)->b_addr))
691
692	struct xfs_agfl {
693	__be32 agfl_magicnum;
694	__be32 agfl_seqno;
695	uuid_t agfl_uuid;
696	__be64 agfl_lsn;
697	__be32 agfl_crc;
698	} __attribute__((packed));
699
700	#define XFS_AGFL_CRC_OFF offsetof(struct xfs_agfl, agfl_crc)
701
702	#define XFS_AGB_TO_FSB(mp,agno,agbno) \
703	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
704	#define XFS_FSB_TO_AGNO(mp,fsbno) \
705	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
706	#define XFS_FSB_TO_AGBNO(mp,fsbno) \
707	((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
708	#define XFS_AGB_TO_DADDR(mp,agno,agbno) \
709	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
710	(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
711	#define XFS_AG_DADDR(mp,agno,d) (XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
712
713	/*
714	* For checking for bad ranges of xfs_daddr_t's, covering multiple
715	* allocation groups or a single xfs_daddr_t that's a superblock copy.
716	*/
717	#define XFS_AG_CHECK_DADDR(mp,d,len) \
718	((len) == 1 ? \
719	ASSERT((d) == XFS_SB_DADDR || \
720	xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
721	ASSERT(xfs_daddr_to_agno(mp, d) == \
722	xfs_daddr_to_agno(mp, (d) + (len) - 1)))
723
724	/*
725	* Realtime bitmap information is accessed by the word, which is currently
726	* stored in host-endian format. Starting with the realtime groups feature,
727	* the words are stored in be32 ondisk.
728	*/
729	union xfs_rtword_raw {
730	__u32 old;
731	__be32 rtg;
732	};
733
734	/*
735	* Realtime summary counts are accessed by the word, which is currently
736	* stored in host-endian format. Starting with the realtime groups feature,
737	* the words are stored in be32 ondisk.
738	*/
739	union xfs_suminfo_raw {
740	__u32 old;
741	__be32 rtg;
742	};
743
744	/*
745	* Realtime allocation groups break the rt section into multiple pieces that
746	* could be locked independently. Realtime block group numbers are 32-bit
747	* quantities. Block numbers within a group are also 32-bit quantities, but
748	* the upper bit must never be set. rtgroup 0 might have a superblock in it,
749	* so the minimum size of an rtgroup is 2 rtx.
750	*/
751	#define XFS_MAX_RGBLOCKS ((xfs_rgblock_t)(1U << 31) - 1)
752	#define XFS_MIN_RGEXTENTS ((xfs_rtxlen_t)2)
753	#define XFS_MAX_RGNUMBER ((xfs_rgnumber_t)(-1U))
754
755	#define XFS_RTSB_MAGIC 0x46726F67 /* 'Frog' */
756
757	/*
758	* Realtime superblock - on disk version. Must be padded to 64 bit alignment.
759	* The first block of the realtime volume contains this superblock.
760	*/
761	struct xfs_rtsb {
762	__be32 rsb_magicnum; /* magic number == XFS_RTSB_MAGIC */
763	__le32 rsb_crc; /* superblock crc */
764
765	__be32 rsb_pad; /* zero */
766	unsigned char rsb_fname[XFSLABEL_MAX]; /* file system name */
767
768	uuid_t rsb_uuid; /* user-visible file system unique id */
769	uuid_t rsb_meta_uuid; /* metadata file system unique id */
770
771	/* must be padded to 64 bit alignment */
772	};
773
774	#define XFS_RTSB_CRC_OFF offsetof(struct xfs_rtsb, rsb_crc)
775	#define XFS_RTSB_DADDR ((xfs_daddr_t)0) /* daddr in rt section */
776
777	/*
778	* XFS Timestamps
779	* ==============
780	*
781	* Traditional ondisk inode timestamps consist of signed 32-bit counters for
782	* seconds and nanoseconds; time zero is the Unix epoch, Jan 1 00:00:00 UTC
783	* 1970, which means that the timestamp epoch is the same as the Unix epoch.
784	* Therefore, the ondisk min and max defined here can be used directly to
785	* constrain the incore timestamps on a Unix system. Note that we actually
786	* encode a __be64 value on disk.
787	*
788	* When the bigtime feature is enabled, ondisk inode timestamps become an
789	* unsigned 64-bit nanoseconds counter. This means that the bigtime inode
790	* timestamp epoch is the start of the classic timestamp range, which is
791	* Dec 13 20:45:52 UTC 1901. Because the epochs are not the same, callers
792	* /must/ use the bigtime conversion functions when encoding and decoding raw
793	* timestamps.
794	*/
795	typedef __be64 xfs_timestamp_t;
796
797	/* Legacy timestamp encoding format. */
798	struct xfs_legacy_timestamp {
799	__be32 t_sec; /* timestamp seconds */
800	__be32 t_nsec; /* timestamp nanoseconds */
801	};
802
803	/*
804	* Smallest possible ondisk seconds value with traditional timestamps. This
805	* corresponds exactly with the incore timestamp Dec 13 20:45:52 UTC 1901.
806	*/
807	#define XFS_LEGACY_TIME_MIN ((int64_t)S32_MIN)
808
809	/*
810	* Largest possible ondisk seconds value with traditional timestamps. This
811	* corresponds exactly with the incore timestamp Jan 19 03:14:07 UTC 2038.
812	*/
813	#define XFS_LEGACY_TIME_MAX ((int64_t)S32_MAX)
814
815	/*
816	* Smallest possible ondisk seconds value with bigtime timestamps. This
817	* corresponds (after conversion to a Unix timestamp) with the traditional
818	* minimum timestamp of Dec 13 20:45:52 UTC 1901.
819	*/
820	#define XFS_BIGTIME_TIME_MIN ((int64_t)0)
821
822	/*
823	* Largest supported ondisk seconds value with bigtime timestamps. This
824	* corresponds (after conversion to a Unix timestamp) with an incore timestamp
825	* of Jul 2 20:20:24 UTC 2486.
826	*
827	* We round down the ondisk limit so that the bigtime quota and inode max
828	* timestamps will be the same.
829	*/
830	#define XFS_BIGTIME_TIME_MAX ((int64_t)((-1ULL / NSEC_PER_SEC) & ~0x3ULL))
831
832	/*
833	* Bigtime epoch is set exactly to the minimum time value that a traditional
834	* 32-bit timestamp can represent when using the Unix epoch as a reference.
835	* Hence the Unix epoch is at a fixed offset into the supported bigtime
836	* timestamp range.
837	*
838	* The bigtime epoch also matches the minimum value an on-disk 32-bit XFS
839	* timestamp can represent so we will not lose any fidelity in converting
840	* to/from unix and bigtime timestamps.
841	*
842	* The following conversion factor converts a seconds counter from the Unix
843	* epoch to the bigtime epoch.
844	*/
845	#define XFS_BIGTIME_EPOCH_OFFSET (-(int64_t)S32_MIN)
846
847	/* Convert a timestamp from the Unix epoch to the bigtime epoch. */
848	static inline uint64_t xfs_unix_to_bigtime(time64_t unix_seconds)
849	{
850	return (uint64_t)unix_seconds + XFS_BIGTIME_EPOCH_OFFSET;
851	}
852
853	/* Convert a timestamp from the bigtime epoch to the Unix epoch. */
854	static inline time64_t xfs_bigtime_to_unix(uint64_t ondisk_seconds)
855	{
856	return (time64_t)ondisk_seconds - XFS_BIGTIME_EPOCH_OFFSET;
857	}
858
859	enum xfs_metafile_type {
860	XFS_METAFILE_UNKNOWN, /* unknown */
861	XFS_METAFILE_DIR, /* metadir directory */
862	XFS_METAFILE_USRQUOTA, /* user quota */
863	XFS_METAFILE_GRPQUOTA, /* group quota */
864	XFS_METAFILE_PRJQUOTA, /* project quota */
865	XFS_METAFILE_RTBITMAP, /* rt bitmap */
866	XFS_METAFILE_RTSUMMARY, /* rt summary */
867	XFS_METAFILE_RTRMAP, /* rt rmap */
868	XFS_METAFILE_RTREFCOUNT, /* rt refcount */
869
870	XFS_METAFILE_MAX
871	} __packed;
872
873	#define XFS_METAFILE_TYPE_STR \
874	{ XFS_METAFILE_UNKNOWN, "unknown" }, \
875	{ XFS_METAFILE_DIR, "dir" }, \
876	{ XFS_METAFILE_USRQUOTA, "usrquota" }, \
877	{ XFS_METAFILE_GRPQUOTA, "grpquota" }, \
878	{ XFS_METAFILE_PRJQUOTA, "prjquota" }, \
879	{ XFS_METAFILE_RTBITMAP, "rtbitmap" }, \
880	{ XFS_METAFILE_RTSUMMARY, "rtsummary" }, \
881	{ XFS_METAFILE_RTRMAP, "rtrmap" }, \
882	{ XFS_METAFILE_RTREFCOUNT, "rtrefcount" }
883
884	/*
885	* On-disk inode structure.
886	*
887	* This is just the header or "dinode core", the inode is expanded to fill a
888	* variable size the leftover area split into a data and an attribute fork.
889	* The format of the data and attribute fork depends on the format of the
890	* inode as indicated by di_format and di_aformat. To access the data and
891	* attribute use the XFS_DFORK_DPTR, XFS_DFORK_APTR, and XFS_DFORK_PTR macros
892	* below.
893	*
894	* There is a very similar struct xfs_log_dinode which matches the layout of
895	* this structure, but is kept in native format instead of big endian.
896	*
897	* Note: di_flushiter is only used by v1/2 inodes - it's effectively a zeroed
898	* padding field for v3 inodes.
899	*/
900	#define XFS_DINODE_MAGIC 0x494e /* 'IN' */
901	struct xfs_dinode {
902	__be16 di_magic; /* inode magic # = XFS_DINODE_MAGIC */
903	__be16 di_mode; /* mode and type of file */
904	__u8 di_version; /* inode version */
905	__u8 di_format; /* format of di_c data */
906	__be16 di_metatype; /* XFS_METAFILE_*; was di_onlink */
907	__be32 di_uid; /* owner's user id */
908	__be32 di_gid; /* owner's group id */
909	__be32 di_nlink; /* number of links to file */
910	__be16 di_projid_lo; /* lower part of owner's project id */
911	__be16 di_projid_hi; /* higher part owner's project id */
912	union {
913	/* Number of data fork extents if NREXT64 is set */
914	__be64 di_big_nextents;
915
916	/* Padding for V3 inodes without NREXT64 set. */
917	__be64 di_v3_pad;
918
919	/* Padding and inode flush counter for V2 inodes. */
920	struct {
921	__u8 di_v2_pad[6];
922	__be16 di_flushiter;
923	};
924	};
925	xfs_timestamp_t di_atime; /* time last accessed */
926	xfs_timestamp_t di_mtime; /* time last modified */
927	xfs_timestamp_t di_ctime; /* time created/inode modified */
928	__be64 di_size; /* number of bytes in file */
929	__be64 di_nblocks; /* # of direct & btree blocks used */
930	__be32 di_extsize; /* basic/minimum extent size for file */
931	union {
932	/*
933	* For V2 inodes and V3 inodes without NREXT64 set, this
934	* is the number of data and attr fork extents.
935	*/
936	struct {
937	__be32 di_nextents;
938	__be16 di_anextents;
939	} __packed;
940
941	/* Number of attr fork extents if NREXT64 is set. */
942	struct {
943	__be32 di_big_anextents;
944	__be16 di_nrext64_pad;
945	} __packed;
946	} __packed;
947	__u8 di_forkoff; /* attr fork offs, <<3 for 64b align */
948	__s8 di_aformat; /* format of attr fork's data */
949	__be32 di_dmevmask; /* DMIG event mask */
950	__be16 di_dmstate; /* DMIG state info */
951	__be16 di_flags; /* random flags, XFS_DIFLAG_... */
952	__be32 di_gen; /* generation number */
953
954	/* di_next_unlinked is the only non-core field in the old dinode */
955	__be32 di_next_unlinked;/* agi unlinked list ptr */
956
957	/* start of the extended dinode, writable fields */
958	__le32 di_crc; /* CRC of the inode */
959	__be64 di_changecount; /* number of attribute changes */
960	__be64 di_lsn; /* flush sequence */
961	__be64 di_flags2; /* more random flags */
962	union {
963	/* basic cow extent size for (regular) file */
964	__be32 di_cowextsize;
965	/* used blocks in RTG for (zoned) rtrmap inode */
966	__be32 di_used_blocks;
967	};
968	__u8 di_pad2[12]; /* more padding for future expansion */
969
970	/* fields only written to during inode creation */
971	xfs_timestamp_t di_crtime; /* time created */
972	__be64 di_ino; /* inode number */
973	uuid_t di_uuid; /* UUID of the filesystem */
974
975	/* structure must be padded to 64 bit alignment */
976	};
977
978	#define XFS_DINODE_CRC_OFF offsetof(struct xfs_dinode, di_crc)
979
980	#define DI_MAX_FLUSH 0xffff
981
982	/*
983	* Size of the core inode on disk. Version 1 and 2 inodes have
984	* the same size, but version 3 has grown a few additional fields.
985	*/
986	static inline uint xfs_dinode_size(int version)
987	{
988	if (version == 3)
989	return sizeof(struct xfs_dinode);
990	return offsetof(struct xfs_dinode, di_crc);
991	}
992
993	/*
994	* The 32 bit link count in the inode theoretically maxes out at UINT_MAX.
995	* Since the pathconf interface is signed, we use 2^31 - 1 instead.
996	*/
997	#define XFS_MAXLINK ((1U << 31) - 1U)
998
999	/*
1000	* Any file that hits the maximum ondisk link count should be pinned to avoid
1001	* a use-after-free situation.
1002	*/
1003	#define XFS_NLINK_PINNED (~0U)
1004
1005	/*
1006	* Values for di_format
1007	*
1008	* This enum is used in string mapping in xfs_trace.h; please keep the
1009	* TRACE_DEFINE_ENUMs for it up to date.
1010	*/
1011	enum xfs_dinode_fmt {
1012	XFS_DINODE_FMT_DEV, /* xfs_dev_t */
1013	XFS_DINODE_FMT_LOCAL, /* bulk data */
1014	XFS_DINODE_FMT_EXTENTS, /* struct xfs_bmbt_rec */
1015	XFS_DINODE_FMT_BTREE, /* struct xfs_bmdr_block */
1016	XFS_DINODE_FMT_UUID, /* added long ago, but never used */
1017	XFS_DINODE_FMT_META_BTREE, /* metadata btree */
1018	};
1019
1020	#define XFS_INODE_FORMAT_STR \
1021	{ XFS_DINODE_FMT_DEV, "dev" }, \
1022	{ XFS_DINODE_FMT_LOCAL, "local" }, \
1023	{ XFS_DINODE_FMT_EXTENTS, "extent" }, \
1024	{ XFS_DINODE_FMT_BTREE, "btree" }, \
1025	{ XFS_DINODE_FMT_UUID, "uuid" }, \
1026	{ XFS_DINODE_FMT_META_BTREE, "meta_btree" }
1027
1028	/*
1029	* Max values for extnum and aextnum.
1030	*
1031	* The original on-disk extent counts were held in signed fields, resulting in
1032	* maximum extent counts of 2^31 and 2^15 for the data and attr forks
1033	* respectively. Similarly the maximum extent length is limited to 2^21 blocks
1034	* by the 21-bit wide blockcount field of a BMBT extent record.
1035	*
1036	* The newly introduced data fork extent counter can hold a 64-bit value,
1037	* however the maximum number of extents in a file is also limited to 2^54
1038	* extents by the 54-bit wide startoff field of a BMBT extent record.
1039	*
1040	* It is further limited by the maximum supported file size of 2^63
1041	* *bytes*. This leads to a maximum extent count for maximally sized filesystem
1042	* blocks (64kB) of:
1043	*
1044	* 2^63 bytes / 2^16 bytes per block = 2^47 blocks
1045	*
1046	* Rounding up 47 to the nearest multiple of bits-per-byte results in 48. Hence
1047	* 2^48 was chosen as the maximum data fork extent count.
1048	*
1049	* The maximum file size that can be represented by the data fork extent counter
1050	* in the worst case occurs when all extents are 1 block in length and each
1051	* block is 1KB in size.
1052	*
1053	* With XFS_MAX_EXTCNT_DATA_FORK_SMALL representing maximum extent count and
1054	* with 1KB sized blocks, a file can reach upto,
1055	* 1KB * (2^31) = 2TB
1056	*
1057	* This is much larger than the theoretical maximum size of a directory
1058	* i.e. XFS_DIR2_SPACE_SIZE * XFS_DIR2_MAX_SPACES = ~96GB.
1059	*
1060	* Hence, a directory inode can never overflow its data fork extent counter.
1061	*/
1062	#define XFS_MAX_EXTCNT_DATA_FORK_LARGE ((xfs_extnum_t)((1ULL << 48) - 1))
1063	#define XFS_MAX_EXTCNT_ATTR_FORK_LARGE ((xfs_extnum_t)((1ULL << 32) - 1))
1064	#define XFS_MAX_EXTCNT_DATA_FORK_SMALL ((xfs_extnum_t)((1ULL << 31) - 1))
1065	#define XFS_MAX_EXTCNT_ATTR_FORK_SMALL ((xfs_extnum_t)((1ULL << 15) - 1))
1066
1067	/*
1068	* When we upgrade an inode to the large extent counts, the maximum value by
1069	* which the extent count can increase is bound by the change in size of the
1070	* on-disk field. No upgrade operation should ever be adding more than a few
1071	* tens of extents, so if we get a really large value it is a sign of a code bug
1072	* or corruption.
1073	*/
1074	#define XFS_MAX_EXTCNT_UPGRADE_NR \
1075	min(XFS_MAX_EXTCNT_ATTR_FORK_LARGE - XFS_MAX_EXTCNT_ATTR_FORK_SMALL, \
1076	XFS_MAX_EXTCNT_DATA_FORK_LARGE - XFS_MAX_EXTCNT_DATA_FORK_SMALL)
1077
1078	/*
1079	* Inode minimum and maximum sizes.
1080	*/
1081	#define XFS_DINODE_MIN_LOG 8
1082	#define XFS_DINODE_MAX_LOG 11
1083	#define XFS_DINODE_MIN_SIZE (1 << XFS_DINODE_MIN_LOG)
1084	#define XFS_DINODE_MAX_SIZE (1 << XFS_DINODE_MAX_LOG)
1085
1086	/*
1087	* Inode size for given fs.
1088	*/
1089	#define XFS_DINODE_SIZE(mp) \
1090	(xfs_has_v3inodes(mp) ? \
1091	sizeof(struct xfs_dinode) : \
1092	offsetof(struct xfs_dinode, di_crc))
1093	#define XFS_LITINO(mp) \
1094	((mp)->m_sb.sb_inodesize - XFS_DINODE_SIZE(mp))
1095
1096	/*
1097	* Inode data & attribute fork sizes, per inode.
1098	*/
1099	#define XFS_DFORK_BOFF(dip) ((int)((dip)->di_forkoff << 3))
1100
1101	#define XFS_DFORK_DSIZE(dip,mp) \
1102	((dip)->di_forkoff ? XFS_DFORK_BOFF(dip) : XFS_LITINO(mp))
1103	#define XFS_DFORK_ASIZE(dip,mp) \
1104	((dip)->di_forkoff ? XFS_LITINO(mp) - XFS_DFORK_BOFF(dip) : 0)
1105	#define XFS_DFORK_SIZE(dip,mp,w) \
1106	((w) == XFS_DATA_FORK ? \
1107	XFS_DFORK_DSIZE(dip, mp) : \
1108	XFS_DFORK_ASIZE(dip, mp))
1109
1110	#define XFS_DFORK_MAXEXT(dip, mp, w) \
1111	(XFS_DFORK_SIZE(dip, mp, w) / sizeof(struct xfs_bmbt_rec))
1112
1113	/*
1114	* Return pointers to the data or attribute forks.
1115	*/
1116	#define XFS_DFORK_DPTR(dip) \
1117	((void *)dip + xfs_dinode_size(dip->di_version))
1118	#define XFS_DFORK_APTR(dip) \
1119	(XFS_DFORK_DPTR(dip) + XFS_DFORK_BOFF(dip))
1120	#define XFS_DFORK_PTR(dip,w) \
1121	((w) == XFS_DATA_FORK ? XFS_DFORK_DPTR(dip) : XFS_DFORK_APTR(dip))
1122
1123	#define XFS_DFORK_FORMAT(dip,w) \
1124	((w) == XFS_DATA_FORK ? \
1125	(dip)->di_format : \
1126	(dip)->di_aformat)
1127
1128	/*
1129	* For block and character special files the 32bit dev_t is stored at the
1130	* beginning of the data fork.
1131	*/
1132	static inline xfs_dev_t xfs_dinode_get_rdev(struct xfs_dinode *dip)
1133	{
1134	return be32_to_cpu(*(__be32 *)XFS_DFORK_DPTR(dip));
1135	}
1136
1137	static inline void xfs_dinode_put_rdev(struct xfs_dinode *dip, xfs_dev_t rdev)
1138	{
1139	*(__be32 *)XFS_DFORK_DPTR(dip) = cpu_to_be32(rdev);
1140	}
1141
1142	/*
1143	* Values for di_flags
1144	*/
1145	#define XFS_DIFLAG_REALTIME_BIT 0 /* file's blocks come from rt area */
1146	#define XFS_DIFLAG_PREALLOC_BIT 1 /* file space has been preallocated */
1147	#define XFS_DIFLAG_NEWRTBM_BIT 2 /* for rtbitmap inode, new format */
1148	#define XFS_DIFLAG_IMMUTABLE_BIT 3 /* inode is immutable */
1149	#define XFS_DIFLAG_APPEND_BIT 4 /* inode is append-only */
1150	#define XFS_DIFLAG_SYNC_BIT 5 /* inode is written synchronously */
1151	#define XFS_DIFLAG_NOATIME_BIT 6 /* do not update atime */
1152	#define XFS_DIFLAG_NODUMP_BIT 7 /* do not dump */
1153	#define XFS_DIFLAG_RTINHERIT_BIT 8 /* create with realtime bit set */
1154	#define XFS_DIFLAG_PROJINHERIT_BIT 9 /* create with parents projid */
1155	#define XFS_DIFLAG_NOSYMLINKS_BIT 10 /* disallow symlink creation */
1156	#define XFS_DIFLAG_EXTSIZE_BIT 11 /* inode extent size allocator hint */
1157	#define XFS_DIFLAG_EXTSZINHERIT_BIT 12 /* inherit inode extent size */
1158	#define XFS_DIFLAG_NODEFRAG_BIT 13 /* do not reorganize/defragment */
1159	#define XFS_DIFLAG_FILESTREAM_BIT 14 /* use filestream allocator */
1160	/* Do not use bit 15, di_flags is legacy and unchanging now */
1161
1162	#define XFS_DIFLAG_REALTIME (1 << XFS_DIFLAG_REALTIME_BIT)
1163	#define XFS_DIFLAG_PREALLOC (1 << XFS_DIFLAG_PREALLOC_BIT)
1164	#define XFS_DIFLAG_NEWRTBM (1 << XFS_DIFLAG_NEWRTBM_BIT)
1165	#define XFS_DIFLAG_IMMUTABLE (1 << XFS_DIFLAG_IMMUTABLE_BIT)
1166	#define XFS_DIFLAG_APPEND (1 << XFS_DIFLAG_APPEND_BIT)
1167	#define XFS_DIFLAG_SYNC (1 << XFS_DIFLAG_SYNC_BIT)
1168	#define XFS_DIFLAG_NOATIME (1 << XFS_DIFLAG_NOATIME_BIT)
1169	#define XFS_DIFLAG_NODUMP (1 << XFS_DIFLAG_NODUMP_BIT)
1170	#define XFS_DIFLAG_RTINHERIT (1 << XFS_DIFLAG_RTINHERIT_BIT)
1171	#define XFS_DIFLAG_PROJINHERIT (1 << XFS_DIFLAG_PROJINHERIT_BIT)
1172	#define XFS_DIFLAG_NOSYMLINKS (1 << XFS_DIFLAG_NOSYMLINKS_BIT)
1173	#define XFS_DIFLAG_EXTSIZE (1 << XFS_DIFLAG_EXTSIZE_BIT)
1174	#define XFS_DIFLAG_EXTSZINHERIT (1 << XFS_DIFLAG_EXTSZINHERIT_BIT)
1175	#define XFS_DIFLAG_NODEFRAG (1 << XFS_DIFLAG_NODEFRAG_BIT)
1176	#define XFS_DIFLAG_FILESTREAM (1 << XFS_DIFLAG_FILESTREAM_BIT)
1177
1178	#define XFS_DIFLAG_ANY \
1179	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
1180	XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
1181	XFS_DIFLAG_NOATIME | XFS_DIFLAG_NODUMP | XFS_DIFLAG_RTINHERIT | \
1182	XFS_DIFLAG_PROJINHERIT | XFS_DIFLAG_NOSYMLINKS | XFS_DIFLAG_EXTSIZE | \
1183	XFS_DIFLAG_EXTSZINHERIT | XFS_DIFLAG_NODEFRAG | XFS_DIFLAG_FILESTREAM)
1184
1185	/*
1186	* Values for di_flags2 These start by being exposed to userspace in the upper
1187	* 16 bits of the XFS_XFLAG_s range.
1188	*/
1189	/* use DAX for this inode */
1190	#define XFS_DIFLAG2_DAX_BIT 0
1191
1192	/* file's blocks may be shared */
1193	#define XFS_DIFLAG2_REFLINK_BIT 1
1194
1195	/* copy on write extent size hint */
1196	#define XFS_DIFLAG2_COWEXTSIZE_BIT 2
1197
1198	/* big timestamps */
1199	#define XFS_DIFLAG2_BIGTIME_BIT 3
1200
1201	/* large extent counters */
1202	#define XFS_DIFLAG2_NREXT64_BIT 4
1203
1204	/*
1205	* The inode contains filesystem metadata and can be found through the metadata
1206	* directory tree. Metadata inodes must satisfy the following constraints:
1207	*
1208	* - V5 filesystem (and ftype) are enabled;
1209	* - The only valid modes are regular files and directories;
1210	* - The access bits must be zero;
1211	* - DMAPI event and state masks are zero;
1212	* - The user and group IDs must be zero;
1213	* - The project ID can be used as a u32 annotation;
1214	* - The immutable, sync, noatime, nodump, nodefrag flags must be set.
1215	* - The dax flag must not be set.
1216	* - Directories must have nosymlinks set.
1217	*
1218	* These requirements are chosen defensively to minimize the ability of
1219	* userspace to read or modify the contents, should a metadata file ever
1220	* escape to userspace.
1221	*
1222	* There are further constraints on the directory tree itself:
1223	*
1224	* - Metadata inodes must never be resolvable through the root directory;
1225	* - They must never be accessed by userspace;
1226	* - Metadata directory entries must have correct ftype.
1227	*
1228	* Superblock-rooted metadata files must have the METADATA iflag set even
1229	* though they do not have a parent directory.
1230	*/
1231	#define XFS_DIFLAG2_METADATA_BIT 5
1232
1233	#define XFS_DIFLAG2_DAX (1ULL << XFS_DIFLAG2_DAX_BIT)
1234	#define XFS_DIFLAG2_REFLINK (1ULL << XFS_DIFLAG2_REFLINK_BIT)
1235	#define XFS_DIFLAG2_COWEXTSIZE (1ULL << XFS_DIFLAG2_COWEXTSIZE_BIT)
1236	#define XFS_DIFLAG2_BIGTIME (1ULL << XFS_DIFLAG2_BIGTIME_BIT)
1237	#define XFS_DIFLAG2_NREXT64 (1ULL << XFS_DIFLAG2_NREXT64_BIT)
1238	#define XFS_DIFLAG2_METADATA (1ULL << XFS_DIFLAG2_METADATA_BIT)
1239
1240	#define XFS_DIFLAG2_ANY \
1241	(XFS_DIFLAG2_DAX | XFS_DIFLAG2_REFLINK | XFS_DIFLAG2_COWEXTSIZE | \
1242	XFS_DIFLAG2_BIGTIME | XFS_DIFLAG2_NREXT64 | XFS_DIFLAG2_METADATA)
1243
1244	static inline bool xfs_dinode_has_bigtime(const struct xfs_dinode *dip)
1245	{
1246	return dip->di_version >= 3 &&
1247	(dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_BIGTIME));
1248	}
1249
1250	static inline bool xfs_dinode_has_large_extent_counts(
1251	const struct xfs_dinode *dip)
1252	{
1253	return dip->di_version >= 3 &&
1254	(dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_NREXT64));
1255	}
1256
1257	static inline bool xfs_dinode_is_metadir(const struct xfs_dinode *dip)
1258	{
1259	return dip->di_version >= 3 &&
1260	(dip->di_flags2 & cpu_to_be64(XFS_DIFLAG2_METADATA));
1261	}
1262
1263	/*
1264	* Inode number format:
1265	* low inopblog bits - offset in block
1266	* next agblklog bits - block number in ag
1267	* next agno_log bits - ag number
1268	* high agno_log-agblklog-inopblog bits - 0
1269	*/
1270	#define XFS_INO_MASK(k) (uint32_t)((1ULL << (k)) - 1)
1271	#define XFS_INO_OFFSET_BITS(mp) (mp)->m_sb.sb_inopblog
1272	#define XFS_INO_AGBNO_BITS(mp) (mp)->m_sb.sb_agblklog
1273	#define XFS_INO_AGINO_BITS(mp) ((mp)->m_ino_geo.agino_log)
1274	#define XFS_INO_AGNO_BITS(mp) (mp)->m_agno_log
1275	#define XFS_INO_BITS(mp) \
1276	XFS_INO_AGNO_BITS(mp) + XFS_INO_AGINO_BITS(mp)
1277	#define XFS_INO_TO_AGNO(mp,i) \
1278	((xfs_agnumber_t)((i) >> XFS_INO_AGINO_BITS(mp)))
1279	#define XFS_INO_TO_AGINO(mp,i) \
1280	((xfs_agino_t)(i) & XFS_INO_MASK(XFS_INO_AGINO_BITS(mp)))
1281	#define XFS_INO_TO_AGBNO(mp,i) \
1282	(((xfs_agblock_t)(i) >> XFS_INO_OFFSET_BITS(mp)) & \
1283	XFS_INO_MASK(XFS_INO_AGBNO_BITS(mp)))
1284	#define XFS_INO_TO_OFFSET(mp,i) \
1285	((int)(i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1286	#define XFS_INO_TO_FSB(mp,i) \
1287	XFS_AGB_TO_FSB(mp, XFS_INO_TO_AGNO(mp,i), XFS_INO_TO_AGBNO(mp,i))
1288	#define XFS_AGINO_TO_INO(mp,a,i) \
1289	(((xfs_ino_t)(a) << XFS_INO_AGINO_BITS(mp)) | (i))
1290	#define XFS_AGINO_TO_AGBNO(mp,i) ((i) >> XFS_INO_OFFSET_BITS(mp))
1291	#define XFS_AGINO_TO_OFFSET(mp,i) \
1292	((i) & XFS_INO_MASK(XFS_INO_OFFSET_BITS(mp)))
1293	#define XFS_OFFBNO_TO_AGINO(mp,b,o) \
1294	((xfs_agino_t)(((b) << XFS_INO_OFFSET_BITS(mp)) | (o)))
1295	#define XFS_FSB_TO_INO(mp, b) ((xfs_ino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1296	#define XFS_AGB_TO_AGINO(mp, b) ((xfs_agino_t)((b) << XFS_INO_OFFSET_BITS(mp)))
1297
1298	#define XFS_MAXINUMBER ((xfs_ino_t)((1ULL << 56) - 1ULL))
1299	#define XFS_MAXINUMBER_32 ((xfs_ino_t)((1ULL << 32) - 1ULL))
1300
1301	/*
1302	* RealTime Device format definitions
1303	*/
1304
1305	/* Min and max rt extent sizes, specified in bytes */
1306	#define XFS_MAX_RTEXTSIZE (1024 * 1024 * 1024) /* 1GB */
1307	#define XFS_DFL_RTEXTSIZE (64 * 1024) /* 64kB */
1308	#define XFS_MIN_RTEXTSIZE (4 * 1024) /* 4kB */
1309
1310	/*
1311	* RT bit manipulation macros.
1312	*/
1313	#define XFS_RTBITMAP_MAGIC 0x424D505A /* BMPZ */
1314	#define XFS_RTSUMMARY_MAGIC 0x53554D59 /* SUMY */
1315
1316	struct xfs_rtbuf_blkinfo {
1317	__be32 rt_magic; /* validity check on block */
1318	__be32 rt_crc; /* CRC of block */
1319	__be64 rt_owner; /* inode that owns the block */
1320	__be64 rt_blkno; /* first block of the buffer */
1321	__be64 rt_lsn; /* sequence number of last write */
1322	uuid_t rt_uuid; /* filesystem we belong to */
1323	};
1324
1325	#define XFS_RTBUF_CRC_OFF \
1326	offsetof(struct xfs_rtbuf_blkinfo, rt_crc)
1327
1328	/*
1329	* Dquot and dquot block format definitions
1330	*/
1331	#define XFS_DQUOT_MAGIC 0x4451 /* 'DQ' */
1332	#define XFS_DQUOT_VERSION (uint8_t)0x01 /* latest version number */
1333
1334	#define XFS_DQTYPE_USER (1u << 0) /* user dquot record */
1335	#define XFS_DQTYPE_PROJ (1u << 1) /* project dquot record */
1336	#define XFS_DQTYPE_GROUP (1u << 2) /* group dquot record */
1337	#define XFS_DQTYPE_BIGTIME (1u << 7) /* large expiry timestamps */
1338
1339	/* bitmask to determine if this is a user/group/project dquot */
1340	#define XFS_DQTYPE_REC_MASK (XFS_DQTYPE_USER | \
1341	XFS_DQTYPE_PROJ | \
1342	XFS_DQTYPE_GROUP)
1343
1344	#define XFS_DQTYPE_ANY (XFS_DQTYPE_REC_MASK | \
1345	XFS_DQTYPE_BIGTIME)
1346
1347	/*
1348	* XFS Quota Timers
1349	* ================
1350	*
1351	* Traditional quota grace period expiration timers are an unsigned 32-bit
1352	* seconds counter; time zero is the Unix epoch, Jan 1 00:00:01 UTC 1970.
1353	* Note that an expiration value of zero means that the quota limit has not
1354	* been reached, and therefore no expiration has been set. Therefore, the
1355	* ondisk min and max defined here can be used directly to constrain the incore
1356	* quota expiration timestamps on a Unix system.
1357	*
1358	* When bigtime is enabled, we trade two bits of precision to expand the
1359	* expiration timeout range to match that of big inode timestamps. The min and
1360	* max recorded here are the on-disk limits, not a Unix timestamp.
1361	*
1362	* The grace period for each quota type is stored in the root dquot (id = 0)
1363	* and is applied to a non-root dquot when it exceeds the soft or hard limits.
1364	* The length of quota grace periods are unsigned 32-bit quantities measured in
1365	* units of seconds. A value of zero means to use the default period.
1366	*/
1367
1368	/*
1369	* Smallest possible ondisk quota expiration value with traditional timestamps.
1370	* This corresponds exactly with the incore expiration Jan 1 00:00:01 UTC 1970.
1371	*/
1372	#define XFS_DQ_LEGACY_EXPIRY_MIN ((int64_t)1)
1373
1374	/*
1375	* Largest possible ondisk quota expiration value with traditional timestamps.
1376	* This corresponds exactly with the incore expiration Feb 7 06:28:15 UTC 2106.
1377	*/
1378	#define XFS_DQ_LEGACY_EXPIRY_MAX ((int64_t)U32_MAX)
1379
1380	/*
1381	* Smallest possible ondisk quota expiration value with bigtime timestamps.
1382	* This corresponds (after conversion to a Unix timestamp) with the incore
1383	* expiration of Jan 1 00:00:04 UTC 1970.
1384	*/
1385	#define XFS_DQ_BIGTIME_EXPIRY_MIN (XFS_DQ_LEGACY_EXPIRY_MIN)
1386
1387	/*
1388	* Largest supported ondisk quota expiration value with bigtime timestamps.
1389	* This corresponds (after conversion to a Unix timestamp) with an incore
1390	* expiration of Jul 2 20:20:24 UTC 2486.
1391	*
1392	* The ondisk field supports values up to -1U, which corresponds to an incore
1393	* expiration in 2514. This is beyond the maximum the bigtime inode timestamp,
1394	* so we cap the maximum bigtime quota expiration to the max inode timestamp.
1395	*/
1396	#define XFS_DQ_BIGTIME_EXPIRY_MAX ((int64_t)4074815106U)
1397
1398	/*
1399	* The following conversion factors assist in converting a quota expiration
1400	* timestamp between the incore and ondisk formats.
1401	*/
1402	#define XFS_DQ_BIGTIME_SHIFT (2)
1403	#define XFS_DQ_BIGTIME_SLACK ((int64_t)(1ULL << XFS_DQ_BIGTIME_SHIFT) - 1)
1404
1405	/* Convert an incore quota expiration timestamp to an ondisk bigtime value. */
1406	static inline uint32_t xfs_dq_unix_to_bigtime(time64_t unix_seconds)
1407	{
1408	/*
1409	* Round the expiration timestamp up to the nearest bigtime timestamp
1410	* that we can store, to give users the most time to fix problems.
1411	*/
1412	return ((uint64_t)unix_seconds + XFS_DQ_BIGTIME_SLACK) >>
1413	XFS_DQ_BIGTIME_SHIFT;
1414	}
1415
1416	/* Convert an ondisk bigtime quota expiration value to an incore timestamp. */
1417	static inline time64_t xfs_dq_bigtime_to_unix(uint32_t ondisk_seconds)
1418	{
1419	return (time64_t)ondisk_seconds << XFS_DQ_BIGTIME_SHIFT;
1420	}
1421
1422	/*
1423	* Default quota grace periods, ranging from zero (use the compiled defaults)
1424	* to ~136 years. These are applied to a non-root dquot that has exceeded
1425	* either limit.
1426	*/
1427	#define XFS_DQ_GRACE_MIN ((int64_t)0)
1428	#define XFS_DQ_GRACE_MAX ((int64_t)U32_MAX)
1429
1430	/* Maximum id value for a quota record */
1431	#define XFS_DQ_ID_MAX (U32_MAX)
1432
1433	/*
1434	* This is the main portion of the on-disk representation of quota information
1435	* for a user. We pad this with some more expansion room to construct the on
1436	* disk structure.
1437	*/
1438	struct xfs_disk_dquot {
1439	__be16 d_magic; /* dquot magic = XFS_DQUOT_MAGIC */
1440	__u8 d_version; /* dquot version */
1441	__u8 d_type; /* XFS_DQTYPE_USER/PROJ/GROUP */
1442	__be32 d_id; /* user,project,group id */
1443	__be64 d_blk_hardlimit;/* absolute limit on disk blks */
1444	__be64 d_blk_softlimit;/* preferred limit on disk blks */
1445	__be64 d_ino_hardlimit;/* maximum # allocated inodes */
1446	__be64 d_ino_softlimit;/* preferred inode limit */
1447	__be64 d_bcount; /* disk blocks owned by the user */
1448	__be64 d_icount; /* inodes owned by the user */
1449	__be32 d_itimer; /* zero if within inode limits if not,
1450	this is when we refuse service */
1451	__be32 d_btimer; /* similar to above; for disk blocks */
1452	__be16 d_iwarns; /* warnings issued wrt num inodes */
1453	__be16 d_bwarns; /* warnings issued wrt disk blocks */
1454	__be32 d_pad0; /* 64 bit align */
1455	__be64 d_rtb_hardlimit;/* absolute limit on realtime blks */
1456	__be64 d_rtb_softlimit;/* preferred limit on RT disk blks */
1457	__be64 d_rtbcount; /* realtime blocks owned */
1458	__be32 d_rtbtimer; /* similar to above; for RT disk blocks */
1459	__be16 d_rtbwarns; /* warnings issued wrt RT disk blocks */
1460	__be16 d_pad;
1461	};
1462
1463	/*
1464	* This is what goes on disk. This is separated from the xfs_disk_dquot because
1465	* carrying the unnecessary padding would be a waste of memory.
1466	*/
1467	struct xfs_dqblk {
1468	struct xfs_disk_dquot dd_diskdq; /* portion living incore as well */
1469	char dd_fill[4];/* filling for posterity */
1470
1471	/*
1472	* These two are only present on filesystems with the CRC bits set.
1473	*/
1474	__be32 dd_crc; /* checksum */
1475	__be64 dd_lsn; /* last modification in log */
1476	uuid_t dd_uuid; /* location information */
1477	};
1478
1479	#define XFS_DQUOT_CRC_OFF offsetof(struct xfs_dqblk, dd_crc)
1480
1481	/*
1482	* This defines the unit of allocation of dquots.
1483	*
1484	* Currently, it is just one file system block, and a 4K blk contains 30
1485	* (136 * 30 = 4080) dquots. It's probably not worth trying to make
1486	* this more dynamic.
1487	*
1488	* However, if this number is changed, we have to make sure that we don't
1489	* implicitly assume that we do allocations in chunks of a single filesystem
1490	* block in the dquot/xqm code.
1491	*
1492	* This is part of the ondisk format because the structure size is not a power
1493	* of two, which leaves slack at the end of the disk block.
1494	*/
1495	#define XFS_DQUOT_CLUSTER_SIZE_FSB (xfs_filblks_t)1
1496
1497	/*
1498	* Remote symlink format and access functions.
1499	*/
1500	#define XFS_SYMLINK_MAGIC 0x58534c4d /* XSLM */
1501
1502	struct xfs_dsymlink_hdr {
1503	__be32 sl_magic;
1504	__be32 sl_offset;
1505	__be32 sl_bytes;
1506	__be32 sl_crc;
1507	uuid_t sl_uuid;
1508	__be64 sl_owner;
1509	__be64 sl_blkno;
1510	__be64 sl_lsn;
1511	};
1512
1513	#define XFS_SYMLINK_CRC_OFF offsetof(struct xfs_dsymlink_hdr, sl_crc)
1514
1515	#define XFS_SYMLINK_MAXLEN 1024
1516	/*
1517	* The maximum pathlen is 1024 bytes. Since the minimum file system
1518	* blocksize is 512 bytes, we can get a max of 3 extents back from
1519	* bmapi when crc headers are taken into account.
1520	*/
1521	#define XFS_SYMLINK_MAPS 3
1522
1523	#define XFS_SYMLINK_BUF_SPACE(mp, bufsize) \
1524	((bufsize) - (xfs_has_crc((mp)) ? \
1525	sizeof(struct xfs_dsymlink_hdr) : 0))
1526
1527
1528	/*
1529	* Allocation Btree format definitions
1530	*
1531	* There are two on-disk btrees, one sorted by blockno and one sorted
1532	* by blockcount and blockno. All blocks look the same to make the code
1533	* simpler; if we have time later, we'll make the optimizations.
1534	*/
1535	#define XFS_ABTB_MAGIC 0x41425442 /* 'ABTB' for bno tree */
1536	#define XFS_ABTB_CRC_MAGIC 0x41423342 /* 'AB3B' */
1537	#define XFS_ABTC_MAGIC 0x41425443 /* 'ABTC' for cnt tree */
1538	#define XFS_ABTC_CRC_MAGIC 0x41423343 /* 'AB3C' */
1539
1540	/*
1541	* Data record/key structure
1542	*/
1543	typedef struct xfs_alloc_rec {
1544	__be32 ar_startblock; /* starting block number */
1545	__be32 ar_blockcount; /* count of free blocks */
1546	} xfs_alloc_rec_t, xfs_alloc_key_t;
1547
1548	typedef struct xfs_alloc_rec_incore {
1549	xfs_agblock_t ar_startblock; /* starting block number */
1550	xfs_extlen_t ar_blockcount; /* count of free blocks */
1551	} xfs_alloc_rec_incore_t;
1552
1553	/* btree pointer type */
1554	typedef __be32 xfs_alloc_ptr_t;
1555
1556	/*
1557	* Block numbers in the AG:
1558	* SB is sector 0, AGF is sector 1, AGI is sector 2, AGFL is sector 3.
1559	*/
1560	#define XFS_BNO_BLOCK(mp) ((xfs_agblock_t)(XFS_AGFL_BLOCK(mp) + 1))
1561	#define XFS_CNT_BLOCK(mp) ((xfs_agblock_t)(XFS_BNO_BLOCK(mp) + 1))
1562
1563
1564	/*
1565	* Inode Allocation Btree format definitions
1566	*
1567	* There is a btree for the inode map per allocation group.
1568	*/
1569	#define XFS_IBT_MAGIC 0x49414254 /* 'IABT' */
1570	#define XFS_IBT_CRC_MAGIC 0x49414233 /* 'IAB3' */
1571	#define XFS_FIBT_MAGIC 0x46494254 /* 'FIBT' */
1572	#define XFS_FIBT_CRC_MAGIC 0x46494233 /* 'FIB3' */
1573
1574	typedef uint64_t xfs_inofree_t;
1575	#define XFS_INODES_PER_CHUNK (NBBY * sizeof(xfs_inofree_t))
1576	#define XFS_INODES_PER_CHUNK_LOG (XFS_NBBYLOG + 3)
1577	#define XFS_INOBT_ALL_FREE ((xfs_inofree_t)-1)
1578	#define XFS_INOBT_MASK(i) ((xfs_inofree_t)1 << (i))
1579
1580	#define XFS_INOBT_HOLEMASK_FULL 0 /* holemask for full chunk */
1581	#define XFS_INOBT_HOLEMASK_BITS (NBBY * sizeof(uint16_t))
1582	#define XFS_INODES_PER_HOLEMASK_BIT \
1583	(XFS_INODES_PER_CHUNK / (NBBY * sizeof(uint16_t)))
1584
1585	static inline xfs_inofree_t xfs_inobt_maskn(int i, int n)
1586	{
1587	return ((n >= XFS_INODES_PER_CHUNK ? 0 : XFS_INOBT_MASK(n)) - 1) << i;
1588	}
1589
1590	/*
1591	* The on-disk inode record structure has two formats. The original "full"
1592	* format uses a 4-byte freecount. The "sparse" format uses a 1-byte freecount
1593	* and replaces the 3 high-order freecount bytes wth the holemask and inode
1594	* count.
1595	*
1596	* The holemask of the sparse record format allows an inode chunk to have holes
1597	* that refer to blocks not owned by the inode record. This facilitates inode
1598	* allocation in the event of severe free space fragmentation.
1599	*/
1600	typedef struct xfs_inobt_rec {
1601	__be32 ir_startino; /* starting inode number */
1602	union {
1603	struct {
1604	__be32 ir_freecount; /* count of free inodes */
1605	} f;
1606	struct {
1607	__be16 ir_holemask;/* hole mask for sparse chunks */
1608	__u8 ir_count; /* total inode count */
1609	__u8 ir_freecount; /* count of free inodes */
1610	} sp;
1611	} ir_u;
1612	__be64 ir_free; /* free inode mask */
1613	} xfs_inobt_rec_t;
1614
1615	typedef struct xfs_inobt_rec_incore {
1616	xfs_agino_t ir_startino; /* starting inode number */
1617	uint16_t ir_holemask; /* hole mask for sparse chunks */
1618	uint8_t ir_count; /* total inode count */
1619	uint8_t ir_freecount; /* count of free inodes (set bits) */
1620	xfs_inofree_t ir_free; /* free inode mask */
1621	} xfs_inobt_rec_incore_t;
1622
1623	static inline bool xfs_inobt_issparse(uint16_t holemask)
1624	{
1625	/* non-zero holemask represents a sparse rec. */
1626	return holemask;
1627	}
1628
1629	/*
1630	* Key structure
1631	*/
1632	typedef struct xfs_inobt_key {
1633	__be32 ir_startino; /* starting inode number */
1634	} xfs_inobt_key_t;
1635
1636	/* btree pointer type */
1637	typedef __be32 xfs_inobt_ptr_t;
1638
1639	/*
1640	* block numbers in the AG.
1641	*/
1642	#define XFS_IBT_BLOCK(mp) ((xfs_agblock_t)(XFS_CNT_BLOCK(mp) + 1))
1643	#define XFS_FIBT_BLOCK(mp) ((xfs_agblock_t)(XFS_IBT_BLOCK(mp) + 1))
1644
1645	/*
1646	* Reverse mapping btree format definitions
1647	*
1648	* There is a btree for the reverse map per allocation group
1649	*/
1650	#define XFS_RMAP_CRC_MAGIC 0x524d4233 /* 'RMB3' */
1651
1652	/*
1653	* Ownership info for an extent. This is used to create reverse-mapping
1654	* entries.
1655	*/
1656	#define XFS_OWNER_INFO_ATTR_FORK (1 << 0)
1657	#define XFS_OWNER_INFO_BMBT_BLOCK (1 << 1)
1658	struct xfs_owner_info {
1659	uint64_t oi_owner;
1660	xfs_fileoff_t oi_offset;
1661	unsigned int oi_flags;
1662	};
1663
1664	/*
1665	* Special owner types.
1666	*
1667	* Seeing as we only support up to 8EB, we have the upper bit of the owner field
1668	* to tell us we have a special owner value. We use these for static metadata
1669	* allocated at mkfs/growfs time, as well as for freespace management metadata.
1670	*/
1671	#define XFS_RMAP_OWN_NULL (-1ULL) /* No owner, for growfs */
1672	#define XFS_RMAP_OWN_UNKNOWN (-2ULL) /* Unknown owner, for EFI recovery */
1673	#define XFS_RMAP_OWN_FS (-3ULL) /* static fs metadata */
1674	#define XFS_RMAP_OWN_LOG (-4ULL) /* static fs metadata */
1675	#define XFS_RMAP_OWN_AG (-5ULL) /* AG freespace btree blocks */
1676	#define XFS_RMAP_OWN_INOBT (-6ULL) /* Inode btree blocks */
1677	#define XFS_RMAP_OWN_INODES (-7ULL) /* Inode chunk */
1678	#define XFS_RMAP_OWN_REFC (-8ULL) /* refcount tree */
1679	#define XFS_RMAP_OWN_COW (-9ULL) /* cow allocations */
1680	#define XFS_RMAP_OWN_MIN (-10ULL) /* guard */
1681
1682	#define XFS_RMAP_NON_INODE_OWNER(owner) (!!((owner) & (1ULL << 63)))
1683
1684	/*
1685	* Data record structure
1686	*/
1687	struct xfs_rmap_rec {
1688	__be32 rm_startblock; /* extent start block */
1689	__be32 rm_blockcount; /* extent length */
1690	__be64 rm_owner; /* extent owner */
1691	__be64 rm_offset; /* offset within the owner */
1692	};
1693
1694	/*
1695	* rmap btree record
1696	* rm_offset:63 is the attribute fork flag
1697	* rm_offset:62 is the bmbt block flag
1698	* rm_offset:61 is the unwritten extent flag (same as l0:63 in bmbt)
1699	* rm_offset:54-60 aren't used and should be zero
1700	* rm_offset:0-53 is the block offset within the inode
1701	*/
1702	#define XFS_RMAP_OFF_ATTR_FORK ((uint64_t)1ULL << 63)
1703	#define XFS_RMAP_OFF_BMBT_BLOCK ((uint64_t)1ULL << 62)
1704	#define XFS_RMAP_OFF_UNWRITTEN ((uint64_t)1ULL << 61)
1705
1706	#define XFS_RMAP_LEN_MAX ((uint32_t)~0U)
1707	#define XFS_RMAP_OFF_FLAGS (XFS_RMAP_OFF_ATTR_FORK | \
1708	XFS_RMAP_OFF_BMBT_BLOCK | \
1709	XFS_RMAP_OFF_UNWRITTEN)
1710	#define XFS_RMAP_OFF_MASK ((uint64_t)0x3FFFFFFFFFFFFFULL)
1711
1712	#define XFS_RMAP_OFF(off) ((off) & XFS_RMAP_OFF_MASK)
1713
1714	#define XFS_RMAP_IS_BMBT_BLOCK(off) (!!((off) & XFS_RMAP_OFF_BMBT_BLOCK))
1715	#define XFS_RMAP_IS_ATTR_FORK(off) (!!((off) & XFS_RMAP_OFF_ATTR_FORK))
1716	#define XFS_RMAP_IS_UNWRITTEN(len) (!!((off) & XFS_RMAP_OFF_UNWRITTEN))
1717
1718	#define RMAPBT_STARTBLOCK_BITLEN 32
1719	#define RMAPBT_BLOCKCOUNT_BITLEN 32
1720	#define RMAPBT_OWNER_BITLEN 64
1721	#define RMAPBT_ATTRFLAG_BITLEN 1
1722	#define RMAPBT_BMBTFLAG_BITLEN 1
1723	#define RMAPBT_EXNTFLAG_BITLEN 1
1724	#define RMAPBT_UNUSED_OFFSET_BITLEN 7
1725	#define RMAPBT_OFFSET_BITLEN 54
1726
1727	/*
1728	* Key structure
1729	*
1730	* We don't use the length for lookups
1731	*/
1732	struct xfs_rmap_key {
1733	__be32 rm_startblock; /* extent start block */
1734	__be64 rm_owner; /* extent owner */
1735	__be64 rm_offset; /* offset within the owner */
1736	} __attribute__((packed));
1737
1738	/* btree pointer type */
1739	typedef __be32 xfs_rmap_ptr_t;
1740
1741	#define XFS_RMAP_BLOCK(mp) \
1742	(xfs_has_finobt(((mp))) ? \
1743	XFS_FIBT_BLOCK(mp) + 1 : \
1744	XFS_IBT_BLOCK(mp) + 1)
1745
1746	/*
1747	* Realtime Reverse mapping btree format definitions
1748	*
1749	* This is a btree for reverse mapping records for realtime volumes
1750	*/
1751	#define XFS_RTRMAP_CRC_MAGIC 0x4d415052 /* 'MAPR' */
1752
1753	/*
1754	* rtrmap root header, on-disk form only.
1755	*/
1756	struct xfs_rtrmap_root {
1757	__be16 bb_level; /* 0 is a leaf */
1758	__be16 bb_numrecs; /* current # of data records */
1759	};
1760
1761	/* inode-based btree pointer type */
1762	typedef __be64 xfs_rtrmap_ptr_t;
1763
1764	/*
1765	* Reference Count Btree format definitions
1766	*
1767	*/
1768	#define XFS_REFC_CRC_MAGIC 0x52334643 /* 'R3FC' */
1769
1770	unsigned int xfs_refc_block(struct xfs_mount *mp);
1771
1772	/*
1773	* Data record/key structure
1774	*
1775	* Each record associates a range of physical blocks (starting at
1776	* rc_startblock and ending rc_blockcount blocks later) with a reference
1777	* count (rc_refcount). Extents that are being used to stage a copy on
1778	* write (CoW) operation are recorded in the refcount btree with a
1779	* refcount of 1. All other records must have a refcount > 1 and must
1780	* track an extent mapped only by file data forks.
1781	*
1782	* Extents with a single owner (attributes, metadata, non-shared file
1783	* data) are not tracked here. Free space is also not tracked here.
1784	* This is consistent with pre-reflink XFS.
1785	*/
1786
1787	/*
1788	* Extents that are being used to stage a copy on write are stored
1789	* in the refcount btree with a refcount of 1 and the upper bit set
1790	* on the startblock. This speeds up mount time deletion of stale
1791	* staging extents because they're all at the right side of the tree.
1792	*/
1793	#define XFS_REFC_COWFLAG (1U << 31)
1794	#define REFCNTBT_COWFLAG_BITLEN 1
1795	#define REFCNTBT_AGBLOCK_BITLEN 31
1796
1797	struct xfs_refcount_rec {
1798	__be32 rc_startblock; /* starting block number */
1799	__be32 rc_blockcount; /* count of blocks */
1800	__be32 rc_refcount; /* number of inodes linked here */
1801	};
1802
1803	struct xfs_refcount_key {
1804	__be32 rc_startblock; /* starting block number */
1805	};
1806
1807	#define XFS_REFC_REFCOUNT_MAX ((xfs_nlink_t)~0U)
1808	#define XFS_REFC_LEN_MAX ((xfs_extlen_t)~0U)
1809
1810	/* btree pointer type */
1811	typedef __be32 xfs_refcount_ptr_t;
1812
1813	/*
1814	* Realtime Reference Count btree format definitions
1815	*
1816	* This is a btree for reference count records for realtime volumes
1817	*/
1818	#define XFS_RTREFC_CRC_MAGIC 0x52434e54 /* 'RCNT' */
1819
1820	/*
1821	* rt refcount root header, on-disk form only.
1822	*/
1823	struct xfs_rtrefcount_root {
1824	__be16 bb_level; /* 0 is a leaf */
1825	__be16 bb_numrecs; /* current # of data records */
1826	};
1827
1828	/* inode-rooted btree pointer type */
1829	typedef __be64 xfs_rtrefcount_ptr_t;
1830
1831	/*
1832	* BMAP Btree format definitions
1833	*
1834	* This includes both the root block definition that sits inside an inode fork
1835	* and the record/pointer formats for the leaf/node in the blocks.
1836	*/
1837	#define XFS_BMAP_MAGIC 0x424d4150 /* 'BMAP' */
1838	#define XFS_BMAP_CRC_MAGIC 0x424d4133 /* 'BMA3' */
1839
1840	/*
1841	* Bmap root header, on-disk form only.
1842	*/
1843	typedef struct xfs_bmdr_block {
1844	__be16 bb_level; /* 0 is a leaf */
1845	__be16 bb_numrecs; /* current # of data records */
1846	} xfs_bmdr_block_t;
1847
1848	/*
1849	* Bmap btree record and extent descriptor.
1850	* l0:63 is an extent flag (value 1 indicates non-normal).
1851	* l0:9-62 are startoff.
1852	* l0:0-8 and l1:21-63 are startblock.
1853	* l1:0-20 are blockcount.
1854	*/
1855	#define BMBT_EXNTFLAG_BITLEN 1
1856	#define BMBT_STARTOFF_BITLEN 54
1857	#define BMBT_STARTBLOCK_BITLEN 52
1858	#define BMBT_BLOCKCOUNT_BITLEN 21
1859
1860	#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
1861	#define BMBT_BLOCKCOUNT_MASK ((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
1862
1863	#define XFS_MAX_BMBT_EXTLEN ((xfs_extlen_t)(BMBT_BLOCKCOUNT_MASK))
1864
1865	/*
1866	* bmbt records have a file offset (block) field that is 54 bits wide, so this
1867	* is the largest xfs_fileoff_t that we ever expect to see.
1868	*/
1869	#define XFS_MAX_FILEOFF (BMBT_STARTOFF_MASK + BMBT_BLOCKCOUNT_MASK)
1870
1871	typedef struct xfs_bmbt_rec {
1872	__be64 l0, l1;
1873	} xfs_bmbt_rec_t;
1874
1875	typedef uint64_t xfs_bmbt_rec_base_t; /* use this for casts */
1876	typedef xfs_bmbt_rec_t xfs_bmdr_rec_t;
1877
1878	/*
1879	* Values and macros for delayed-allocation startblock fields.
1880	*/
1881	#define STARTBLOCKVALBITS 17
1882	#define STARTBLOCKMASKBITS (15 + 20)
1883	#define STARTBLOCKMASK \
1884	(((((xfs_fsblock_t)1) << STARTBLOCKMASKBITS) - 1) << STARTBLOCKVALBITS)
1885
1886	static inline int isnullstartblock(xfs_fsblock_t x)
1887	{
1888	return ((x) & STARTBLOCKMASK) == STARTBLOCKMASK;
1889	}
1890
1891	static inline xfs_fsblock_t nullstartblock(int k)
1892	{
1893	ASSERT(k < (1 << STARTBLOCKVALBITS));
1894	return STARTBLOCKMASK | (k);
1895	}
1896
1897	static inline xfs_filblks_t startblockval(xfs_fsblock_t x)
1898	{
1899	return (xfs_filblks_t)((x) & ~STARTBLOCKMASK);
1900	}
1901
1902	/*
1903	* Key structure for non-leaf levels of the tree.
1904	*/
1905	typedef struct xfs_bmbt_key {
1906	__be64 br_startoff; /* starting file offset */
1907	} xfs_bmbt_key_t, xfs_bmdr_key_t;
1908
1909	/* btree pointer type */
1910	typedef __be64 xfs_bmbt_ptr_t, xfs_bmdr_ptr_t;
1911
1912
1913	/*
1914	* Generic Btree block format definitions
1915	*
1916	* This is a combination of the actual format used on disk for short and long
1917	* format btrees. The first three fields are shared by both format, but the
1918	* pointers are different and should be used with care.
1919	*
1920	* To get the size of the actual short or long form headers please use the size
1921	* macros below. Never use sizeof(xfs_btree_block).
1922	*
1923	* The blkno, crc, lsn, owner and uuid fields are only available in filesystems
1924	* with the crc feature bit, and all accesses to them must be conditional on
1925	* that flag.
1926	*/
1927	/* short form block header */
1928	struct xfs_btree_block_shdr {
1929	__be32 bb_leftsib;
1930	__be32 bb_rightsib;
1931
1932	__be64 bb_blkno;
1933	__be64 bb_lsn;
1934	uuid_t bb_uuid;
1935	__be32 bb_owner;
1936	__le32 bb_crc;
1937	};
1938
1939	/* long form block header */
1940	struct xfs_btree_block_lhdr {
1941	__be64 bb_leftsib;
1942	__be64 bb_rightsib;
1943
1944	__be64 bb_blkno;
1945	__be64 bb_lsn;
1946	uuid_t bb_uuid;
1947	__be64 bb_owner;
1948	__le32 bb_crc;
1949	__be32 bb_pad; /* padding for alignment */
1950	};
1951
1952	struct xfs_btree_block {
1953	__be32 bb_magic; /* magic number for block type */
1954	__be16 bb_level; /* 0 is a leaf */
1955	__be16 bb_numrecs; /* current # of data records */
1956	union {
1957	struct xfs_btree_block_shdr s;
1958	struct xfs_btree_block_lhdr l;
1959	} bb_u; /* rest */
1960	};
1961
1962	/* size of a short form block */
1963	#define XFS_BTREE_SBLOCK_LEN \
1964	(offsetof(struct xfs_btree_block, bb_u) + \
1965	offsetof(struct xfs_btree_block_shdr, bb_blkno))
1966	/* size of a long form block */
1967	#define XFS_BTREE_LBLOCK_LEN \
1968	(offsetof(struct xfs_btree_block, bb_u) + \
1969	offsetof(struct xfs_btree_block_lhdr, bb_blkno))
1970
1971	/* sizes of CRC enabled btree blocks */
1972	#define XFS_BTREE_SBLOCK_CRC_LEN \
1973	(offsetof(struct xfs_btree_block, bb_u) + \
1974	sizeof(struct xfs_btree_block_shdr))
1975	#define XFS_BTREE_LBLOCK_CRC_LEN \
1976	(offsetof(struct xfs_btree_block, bb_u) + \
1977	sizeof(struct xfs_btree_block_lhdr))
1978
1979	#define XFS_BTREE_SBLOCK_CRC_OFF \
1980	offsetof(struct xfs_btree_block, bb_u.s.bb_crc)
1981	#define XFS_BTREE_LBLOCK_CRC_OFF \
1982	offsetof(struct xfs_btree_block, bb_u.l.bb_crc)
1983
1984	/*
1985	* On-disk XFS access control list structure.
1986	*/
1987	struct xfs_acl_entry {
1988	__be32 ae_tag;
1989	__be32 ae_id;
1990	__be16 ae_perm;
1991	__be16 ae_pad; /* fill the implicit hole in the structure */
1992	};
1993
1994	struct xfs_acl {
1995	__be32 acl_cnt;
1996	struct xfs_acl_entry acl_entry[];
1997	};
1998
1999	/*
2000	* The number of ACL entries allowed is defined by the on-disk format.
2001	* For v4 superblocks, that is limited to 25 entries. For v5 superblocks, it is
2002	* limited only by the maximum size of the xattr that stores the information.
2003	*/
2004	#define XFS_ACL_MAX_ENTRIES(mp) \
2005	(xfs_has_crc(mp) \
2006	? (XFS_XATTR_SIZE_MAX - sizeof(struct xfs_acl)) / \
2007	sizeof(struct xfs_acl_entry) \
2008	: 25)
2009
2010	#define XFS_ACL_SIZE(cnt) \
2011	(sizeof(struct xfs_acl) + \
2012	sizeof(struct xfs_acl_entry) * cnt)
2013
2014	#define XFS_ACL_MAX_SIZE(mp) \
2015	XFS_ACL_SIZE(XFS_ACL_MAX_ENTRIES((mp)))
2016
2017
2018	/* On-disk XFS extended attribute names */
2019	#define SGI_ACL_FILE "SGI_ACL_FILE"
2020	#define SGI_ACL_DEFAULT "SGI_ACL_DEFAULT"
2021	#define SGI_ACL_FILE_SIZE (sizeof(SGI_ACL_FILE)-1)
2022	#define SGI_ACL_DEFAULT_SIZE (sizeof(SGI_ACL_DEFAULT)-1)
2023
2024	#endif /* __XFS_FORMAT_H__ */
2025