1/*
2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17 */
18#ifndef __XFS_AG_H__
19#define	__XFS_AG_H__
20
21/*
22 * Allocation group header
23 * This is divided into three structures, placed in sequential 512-byte
24 * buffers after a copy of the superblock (also in a 512-byte buffer).
25 */
26
27struct xfs_buf;
28struct xfs_mount;
29struct xfs_trans;
30
31#define	XFS_AGF_MAGIC	0x58414746	/* 'XAGF' */
32#define	XFS_AGI_MAGIC	0x58414749	/* 'XAGI' */
33#define	XFS_AGF_VERSION	1
34#define	XFS_AGI_VERSION	1
35
36#define	XFS_AGF_GOOD_VERSION(v)	((v) == XFS_AGF_VERSION)
37#define	XFS_AGI_GOOD_VERSION(v)	((v) == XFS_AGI_VERSION)
38
39/*
40 * Btree number 0 is bno, 1 is cnt.  This value gives the size of the
41 * arrays below.
42 */
43#define	XFS_BTNUM_AGF	((int)XFS_BTNUM_CNTi + 1)
44
45/*
46 * The second word of agf_levels in the first a.g. overlaps the EFS
47 * superblock's magic number.  Since the magic numbers valid for EFS
48 * are > 64k, our value cannot be confused for an EFS superblock's.
49 */
50
51typedef struct xfs_agf {
52	/*
53	 * Common allocation group header information
54	 */
55	__be32		agf_magicnum;	/* magic number == XFS_AGF_MAGIC */
56	__be32		agf_versionnum;	/* header version == XFS_AGF_VERSION */
57	__be32		agf_seqno;	/* sequence # starting from 0 */
58	__be32		agf_length;	/* size in blocks of a.g. */
59	/*
60	 * Freespace information
61	 */
62	__be32		agf_roots[XFS_BTNUM_AGF];	/* root blocks */
63	__be32		agf_spare0;	/* spare field */
64	__be32		agf_levels[XFS_BTNUM_AGF];	/* btree levels */
65	__be32		agf_spare1;	/* spare field */
66	__be32		agf_flfirst;	/* first freelist block's index */
67	__be32		agf_fllast;	/* last freelist block's index */
68	__be32		agf_flcount;	/* count of blocks in freelist */
69	__be32		agf_freeblks;	/* total free blocks */
70	__be32		agf_longest;	/* longest free space */
71} xfs_agf_t;
72
73#define	XFS_AGF_MAGICNUM	0x00000001
74#define	XFS_AGF_VERSIONNUM	0x00000002
75#define	XFS_AGF_SEQNO		0x00000004
76#define	XFS_AGF_LENGTH		0x00000008
77#define	XFS_AGF_ROOTS		0x00000010
78#define	XFS_AGF_LEVELS		0x00000020
79#define	XFS_AGF_FLFIRST		0x00000040
80#define	XFS_AGF_FLLAST		0x00000080
81#define	XFS_AGF_FLCOUNT		0x00000100
82#define	XFS_AGF_FREEBLKS	0x00000200
83#define	XFS_AGF_LONGEST		0x00000400
84#define	XFS_AGF_NUM_BITS	11
85#define	XFS_AGF_ALL_BITS	((1 << XFS_AGF_NUM_BITS) - 1)
86
87/* disk block (xfs_daddr_t) in the AG */
88#define XFS_AGF_DADDR(mp)	((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
89#define	XFS_AGF_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
90#define	XFS_BUF_TO_AGF(bp)	((xfs_agf_t *)XFS_BUF_PTR(bp))
91
92
93/*
94 * Size of the unlinked inode hash table in the agi.
95 */
96#define	XFS_AGI_UNLINKED_BUCKETS	64
97
98typedef struct xfs_agi {
99	/*
100	 * Common allocation group header information
101	 */
102	__be32		agi_magicnum;	/* magic number == XFS_AGI_MAGIC */
103	__be32		agi_versionnum;	/* header version == XFS_AGI_VERSION */
104	__be32		agi_seqno;	/* sequence # starting from 0 */
105	__be32		agi_length;	/* size in blocks of a.g. */
106	/*
107	 * Inode information
108	 * Inodes are mapped by interpreting the inode number, so no
109	 * mapping data is needed here.
110	 */
111	__be32		agi_count;	/* count of allocated inodes */
112	__be32		agi_root;	/* root of inode btree */
113	__be32		agi_level;	/* levels in inode btree */
114	__be32		agi_freecount;	/* number of free inodes */
115	__be32		agi_newino;	/* new inode just allocated */
116	__be32		agi_dirino;	/* last directory inode chunk */
117	/*
118	 * Hash table of inodes which have been unlinked but are
119	 * still being referenced.
120	 */
121	__be32		agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
122} xfs_agi_t;
123
124#define	XFS_AGI_MAGICNUM	0x00000001
125#define	XFS_AGI_VERSIONNUM	0x00000002
126#define	XFS_AGI_SEQNO		0x00000004
127#define	XFS_AGI_LENGTH		0x00000008
128#define	XFS_AGI_COUNT		0x00000010
129#define	XFS_AGI_ROOT		0x00000020
130#define	XFS_AGI_LEVEL		0x00000040
131#define	XFS_AGI_FREECOUNT	0x00000080
132#define	XFS_AGI_NEWINO		0x00000100
133#define	XFS_AGI_DIRINO		0x00000200
134#define	XFS_AGI_UNLINKED	0x00000400
135#define	XFS_AGI_NUM_BITS	11
136#define	XFS_AGI_ALL_BITS	((1 << XFS_AGI_NUM_BITS) - 1)
137
138/* disk block (xfs_daddr_t) in the AG */
139#define XFS_AGI_DADDR(mp)	((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
140#define	XFS_AGI_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
141#define	XFS_BUF_TO_AGI(bp)	((xfs_agi_t *)XFS_BUF_PTR(bp))
142
143/*
144 * The third a.g. block contains the a.g. freelist, an array
145 * of block pointers to blocks owned by the allocation btree code.
146 */
147#define XFS_AGFL_DADDR(mp)	((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
148#define	XFS_AGFL_BLOCK(mp)	XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
149#define XFS_AGFL_SIZE(mp)	((mp)->m_sb.sb_sectsize / sizeof(xfs_agblock_t))
150#define	XFS_BUF_TO_AGFL(bp)	((xfs_agfl_t *)XFS_BUF_PTR(bp))
151
152typedef struct xfs_agfl {
153	__be32		agfl_bno[1];	/* actually XFS_AGFL_SIZE(mp) */
154} xfs_agfl_t;
155
156/*
157 * Busy block/extent entry.  Used in perag to mark blocks that have been freed
158 * but whose transactions aren't committed to disk yet.
159 */
160typedef struct xfs_perag_busy {
161	xfs_agblock_t	busy_start;
162	xfs_extlen_t	busy_length;
163	struct xfs_trans *busy_tp;	/* transaction that did the free */
164} xfs_perag_busy_t;
165
166/*
167 * Per-ag incore structure, copies of information in agf and agi,
168 * to improve the performance of allocation group selection.
169 *
170 * pick sizes which fit in allocation buckets well
171 */
172#if (BITS_PER_LONG == 32)
173#define XFS_PAGB_NUM_SLOTS	84
174#elif (BITS_PER_LONG == 64)
175#define XFS_PAGB_NUM_SLOTS	128
176#endif
177
178typedef struct xfs_perag
179{
180	char		pagf_init;	/* this agf's entry is initialized */
181	char		pagi_init;	/* this agi's entry is initialized */
182	char		pagf_metadata;	/* the agf is preferred to be metadata */
183	char		pagi_inodeok;	/* The agi is ok for inodes */
184	__uint8_t	pagf_levels[XFS_BTNUM_AGF];
185					/* # of levels in bno & cnt btree */
186	__uint32_t	pagf_flcount;	/* count of blocks in freelist */
187	xfs_extlen_t	pagf_freeblks;	/* total free blocks */
188	xfs_extlen_t	pagf_longest;	/* longest free space */
189	xfs_agino_t	pagi_freecount;	/* number of free inodes */
190#ifdef __KERNEL__
191	lock_t		pagb_lock;	/* lock for pagb_list */
192#endif
193	int		pagb_count;	/* pagb slots in use */
194	xfs_perag_busy_t *pagb_list;	/* unstable blocks */
195} xfs_perag_t;
196
197#define	XFS_AG_MAXLEVELS(mp)		((mp)->m_ag_maxlevels)
198#define	XFS_MIN_FREELIST_RAW(bl,cl,mp)	\
199	(MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp)))
200#define	XFS_MIN_FREELIST(a,mp)		\
201	(XFS_MIN_FREELIST_RAW(		\
202		be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \
203		be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp))
204#define	XFS_MIN_FREELIST_PAG(pag,mp)	\
205	(XFS_MIN_FREELIST_RAW(		\
206		(uint_t)(pag)->pagf_levels[XFS_BTNUM_BNOi], \
207		(uint_t)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp))
208
209#define XFS_AGB_TO_FSB(mp,agno,agbno)	\
210	(((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
211#define	XFS_FSB_TO_AGNO(mp,fsbno)	\
212	((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
213#define	XFS_FSB_TO_AGBNO(mp,fsbno)	\
214	((xfs_agblock_t)((fsbno) & XFS_MASK32LO((mp)->m_sb.sb_agblklog)))
215#define	XFS_AGB_TO_DADDR(mp,agno,agbno)	\
216	((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
217		(xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
218#define	XFS_AG_DADDR(mp,agno,d)		(XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
219
220/*
221 * For checking for bad ranges of xfs_daddr_t's, covering multiple
222 * allocation groups or a single xfs_daddr_t that's a superblock copy.
223 */
224#define	XFS_AG_CHECK_DADDR(mp,d,len)	\
225	((len) == 1 ? \
226	    ASSERT((d) == XFS_SB_DADDR || \
227		   XFS_DADDR_TO_AGBNO(mp, d) != XFS_SB_DADDR) : \
228	    ASSERT(XFS_DADDR_TO_AGNO(mp, d) == \
229		   XFS_DADDR_TO_AGNO(mp, (d) + (len) - 1)))
230
231#endif	/* __XFS_AG_H__ */
232