2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
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.
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.
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
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).
31 #define XFS_AGF_MAGIC 0x58414746 /* 'XAGF' */
32 #define XFS_AGI_MAGIC 0x58414749 /* 'XAGI' */
33 #define XFS_AGFL_MAGIC 0x5841464c /* 'XAFL' */
34 #define XFS_AGF_VERSION 1
35 #define XFS_AGI_VERSION 1
37 #define XFS_AGF_GOOD_VERSION(v) ((v) == XFS_AGF_VERSION)
38 #define XFS_AGI_GOOD_VERSION(v) ((v) == XFS_AGI_VERSION)
41 * Btree number 0 is bno, 1 is cnt. This value gives the size of the
44 #define XFS_BTNUM_AGF ((int)XFS_BTNUM_CNTi + 1)
47 * The second word of agf_levels in the first a.g. overlaps the EFS
48 * superblock's magic number. Since the magic numbers valid for EFS
49 * are > 64k, our value cannot be confused for an EFS superblock's.
52 typedef struct xfs_agf
{
54 * Common allocation group header information
56 __be32 agf_magicnum
; /* magic number == XFS_AGF_MAGIC */
57 __be32 agf_versionnum
; /* header version == XFS_AGF_VERSION */
58 __be32 agf_seqno
; /* sequence # starting from 0 */
59 __be32 agf_length
; /* size in blocks of a.g. */
61 * Freespace information
63 __be32 agf_roots
[XFS_BTNUM_AGF
]; /* root blocks */
64 __be32 agf_spare0
; /* spare field */
65 __be32 agf_levels
[XFS_BTNUM_AGF
]; /* btree levels */
66 __be32 agf_spare1
; /* spare field */
68 __be32 agf_flfirst
; /* first freelist block's index */
69 __be32 agf_fllast
; /* last freelist block's index */
70 __be32 agf_flcount
; /* count of blocks in freelist */
71 __be32 agf_freeblks
; /* total free blocks */
73 __be32 agf_longest
; /* longest free space */
74 __be32 agf_btreeblks
; /* # of blocks held in AGF btrees */
75 uuid_t agf_uuid
; /* uuid of filesystem */
78 * reserve some contiguous space for future logged fields before we add
79 * the unlogged fields. This makes the range logging via flags and
80 * structure offsets much simpler.
82 __be64 agf_spare64
[16];
84 /* unlogged fields, written during buffer writeback. */
85 __be64 agf_lsn
; /* last write sequence */
86 __be32 agf_crc
; /* crc of agf sector */
89 /* structure must be padded to 64 bit alignment */
92 #define XFS_AGF_MAGICNUM 0x00000001
93 #define XFS_AGF_VERSIONNUM 0x00000002
94 #define XFS_AGF_SEQNO 0x00000004
95 #define XFS_AGF_LENGTH 0x00000008
96 #define XFS_AGF_ROOTS 0x00000010
97 #define XFS_AGF_LEVELS 0x00000020
98 #define XFS_AGF_FLFIRST 0x00000040
99 #define XFS_AGF_FLLAST 0x00000080
100 #define XFS_AGF_FLCOUNT 0x00000100
101 #define XFS_AGF_FREEBLKS 0x00000200
102 #define XFS_AGF_LONGEST 0x00000400
103 #define XFS_AGF_BTREEBLKS 0x00000800
104 #define XFS_AGF_UUID 0x00001000
105 #define XFS_AGF_NUM_BITS 13
106 #define XFS_AGF_ALL_BITS ((1 << XFS_AGF_NUM_BITS) - 1)
108 #define XFS_AGF_FLAGS \
109 { XFS_AGF_MAGICNUM, "MAGICNUM" }, \
110 { XFS_AGF_VERSIONNUM, "VERSIONNUM" }, \
111 { XFS_AGF_SEQNO, "SEQNO" }, \
112 { XFS_AGF_LENGTH, "LENGTH" }, \
113 { XFS_AGF_ROOTS, "ROOTS" }, \
114 { XFS_AGF_LEVELS, "LEVELS" }, \
115 { XFS_AGF_FLFIRST, "FLFIRST" }, \
116 { XFS_AGF_FLLAST, "FLLAST" }, \
117 { XFS_AGF_FLCOUNT, "FLCOUNT" }, \
118 { XFS_AGF_FREEBLKS, "FREEBLKS" }, \
119 { XFS_AGF_LONGEST, "LONGEST" }, \
120 { XFS_AGF_BTREEBLKS, "BTREEBLKS" }, \
121 { XFS_AGF_UUID, "UUID" }
123 /* disk block (xfs_daddr_t) in the AG */
124 #define XFS_AGF_DADDR(mp) ((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
125 #define XFS_AGF_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
126 #define XFS_BUF_TO_AGF(bp) ((xfs_agf_t *)((bp)->b_addr))
128 extern int xfs_read_agf(struct xfs_mount
*mp
, struct xfs_trans
*tp
,
129 xfs_agnumber_t agno
, int flags
, struct xfs_buf
**bpp
);
131 extern const struct xfs_buf_ops xfs_agf_buf_ops
;
134 * Size of the unlinked inode hash table in the agi.
136 #define XFS_AGI_UNLINKED_BUCKETS 64
138 typedef struct xfs_agi
{
140 * Common allocation group header information
142 __be32 agi_magicnum
; /* magic number == XFS_AGI_MAGIC */
143 __be32 agi_versionnum
; /* header version == XFS_AGI_VERSION */
144 __be32 agi_seqno
; /* sequence # starting from 0 */
145 __be32 agi_length
; /* size in blocks of a.g. */
148 * Inodes are mapped by interpreting the inode number, so no
149 * mapping data is needed here.
151 __be32 agi_count
; /* count of allocated inodes */
152 __be32 agi_root
; /* root of inode btree */
153 __be32 agi_level
; /* levels in inode btree */
154 __be32 agi_freecount
; /* number of free inodes */
156 __be32 agi_newino
; /* new inode just allocated */
157 __be32 agi_dirino
; /* last directory inode chunk */
159 * Hash table of inodes which have been unlinked but are
160 * still being referenced.
162 __be32 agi_unlinked
[XFS_AGI_UNLINKED_BUCKETS
];
164 uuid_t agi_uuid
; /* uuid of filesystem */
165 __be32 agi_crc
; /* crc of agi sector */
167 __be64 agi_lsn
; /* last write sequence */
169 /* structure must be padded to 64 bit alignment */
172 #define XFS_AGI_MAGICNUM 0x00000001
173 #define XFS_AGI_VERSIONNUM 0x00000002
174 #define XFS_AGI_SEQNO 0x00000004
175 #define XFS_AGI_LENGTH 0x00000008
176 #define XFS_AGI_COUNT 0x00000010
177 #define XFS_AGI_ROOT 0x00000020
178 #define XFS_AGI_LEVEL 0x00000040
179 #define XFS_AGI_FREECOUNT 0x00000080
180 #define XFS_AGI_NEWINO 0x00000100
181 #define XFS_AGI_DIRINO 0x00000200
182 #define XFS_AGI_UNLINKED 0x00000400
183 #define XFS_AGI_NUM_BITS 11
184 #define XFS_AGI_ALL_BITS ((1 << XFS_AGI_NUM_BITS) - 1)
186 /* disk block (xfs_daddr_t) in the AG */
187 #define XFS_AGI_DADDR(mp) ((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
188 #define XFS_AGI_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
189 #define XFS_BUF_TO_AGI(bp) ((xfs_agi_t *)((bp)->b_addr))
191 extern int xfs_read_agi(struct xfs_mount
*mp
, struct xfs_trans
*tp
,
192 xfs_agnumber_t agno
, struct xfs_buf
**bpp
);
194 extern const struct xfs_buf_ops xfs_agi_buf_ops
;
197 * The third a.g. block contains the a.g. freelist, an array
198 * of block pointers to blocks owned by the allocation btree code.
200 #define XFS_AGFL_DADDR(mp) ((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
201 #define XFS_AGFL_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
202 #define XFS_BUF_TO_AGFL(bp) ((xfs_agfl_t *)((bp)->b_addr))
204 #define XFS_BUF_TO_AGFL_BNO(mp, bp) \
205 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
206 &(XFS_BUF_TO_AGFL(bp)->agfl_bno[0]) : \
207 (__be32 *)(bp)->b_addr)
210 * Size of the AGFL. For CRC-enabled filesystes we steal a couple of
211 * slots in the beginning of the block for a proper header with the
212 * location information and CRC.
214 #define XFS_AGFL_SIZE(mp) \
215 (((mp)->m_sb.sb_sectsize - \
216 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \
217 sizeof(struct xfs_agfl) : 0)) / \
218 sizeof(xfs_agblock_t))
220 typedef struct xfs_agfl
{
221 __be32 agfl_magicnum
;
226 __be32 agfl_bno
[]; /* actually XFS_AGFL_SIZE(mp) */
230 * tags for inode radix tree
232 #define XFS_ICI_NO_TAG (-1) /* special flag for an untagged lookup
233 in xfs_inode_ag_iterator */
234 #define XFS_ICI_RECLAIM_TAG 0 /* inode is to be reclaimed */
235 #define XFS_ICI_EOFBLOCKS_TAG 1 /* inode has blocks beyond EOF */
237 #define XFS_AG_MAXLEVELS(mp) ((mp)->m_ag_maxlevels)
238 #define XFS_MIN_FREELIST_RAW(bl,cl,mp) \
239 (MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp)))
240 #define XFS_MIN_FREELIST(a,mp) \
241 (XFS_MIN_FREELIST_RAW( \
242 be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \
243 be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp))
244 #define XFS_MIN_FREELIST_PAG(pag,mp) \
245 (XFS_MIN_FREELIST_RAW( \
246 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_BNOi], \
247 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp))
249 #define XFS_AGB_TO_FSB(mp,agno,agbno) \
250 (((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
251 #define XFS_FSB_TO_AGNO(mp,fsbno) \
252 ((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
253 #define XFS_FSB_TO_AGBNO(mp,fsbno) \
254 ((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
255 #define XFS_AGB_TO_DADDR(mp,agno,agbno) \
256 ((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
257 (xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
258 #define XFS_AG_DADDR(mp,agno,d) (XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
261 * For checking for bad ranges of xfs_daddr_t's, covering multiple
262 * allocation groups or a single xfs_daddr_t that's a superblock copy.
264 #define XFS_AG_CHECK_DADDR(mp,d,len) \
266 ASSERT((d) == XFS_SB_DADDR || \
267 xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
268 ASSERT(xfs_daddr_to_agno(mp, d) == \
269 xfs_daddr_to_agno(mp, (d) + (len) - 1)))
271 #endif /* __XFS_AG_H__ */