Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / fs / xfs / xfs_ag.h
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1 /*
2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
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
18 #ifndef __XFS_AG_H__
19 #define __XFS_AG_H__
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).
27 struct xfs_buf;
28 struct xfs_mount;
29 struct xfs_trans;
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
36 #define XFS_AGF_GOOD_VERSION(v) ((v) == XFS_AGF_VERSION)
37 #define XFS_AGI_GOOD_VERSION(v) ((v) == XFS_AGI_VERSION)
40 * Btree number 0 is bno, 1 is cnt. This value gives the size of the
41 * arrays below.
43 #define XFS_BTNUM_AGF ((int)XFS_BTNUM_CNTi + 1)
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.
51 typedef struct xfs_agf {
53 * Common allocation group header information
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. */
60 * Freespace information
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 __be32 agf_btreeblks; /* # of blocks held in AGF btrees */
72 } xfs_agf_t;
74 #define XFS_AGF_MAGICNUM 0x00000001
75 #define XFS_AGF_VERSIONNUM 0x00000002
76 #define XFS_AGF_SEQNO 0x00000004
77 #define XFS_AGF_LENGTH 0x00000008
78 #define XFS_AGF_ROOTS 0x00000010
79 #define XFS_AGF_LEVELS 0x00000020
80 #define XFS_AGF_FLFIRST 0x00000040
81 #define XFS_AGF_FLLAST 0x00000080
82 #define XFS_AGF_FLCOUNT 0x00000100
83 #define XFS_AGF_FREEBLKS 0x00000200
84 #define XFS_AGF_LONGEST 0x00000400
85 #define XFS_AGF_BTREEBLKS 0x00000800
86 #define XFS_AGF_NUM_BITS 12
87 #define XFS_AGF_ALL_BITS ((1 << XFS_AGF_NUM_BITS) - 1)
89 #define XFS_AGF_FLAGS \
90 { XFS_AGF_MAGICNUM, "MAGICNUM" }, \
91 { XFS_AGF_VERSIONNUM, "VERSIONNUM" }, \
92 { XFS_AGF_SEQNO, "SEQNO" }, \
93 { XFS_AGF_LENGTH, "LENGTH" }, \
94 { XFS_AGF_ROOTS, "ROOTS" }, \
95 { XFS_AGF_LEVELS, "LEVELS" }, \
96 { XFS_AGF_FLFIRST, "FLFIRST" }, \
97 { XFS_AGF_FLLAST, "FLLAST" }, \
98 { XFS_AGF_FLCOUNT, "FLCOUNT" }, \
99 { XFS_AGF_FREEBLKS, "FREEBLKS" }, \
100 { XFS_AGF_LONGEST, "LONGEST" }, \
101 { XFS_AGF_BTREEBLKS, "BTREEBLKS" }
103 /* disk block (xfs_daddr_t) in the AG */
104 #define XFS_AGF_DADDR(mp) ((xfs_daddr_t)(1 << (mp)->m_sectbb_log))
105 #define XFS_AGF_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp))
106 #define XFS_BUF_TO_AGF(bp) ((xfs_agf_t *)((bp)->b_addr))
108 extern int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp,
109 xfs_agnumber_t agno, int flags, struct xfs_buf **bpp);
112 * Size of the unlinked inode hash table in the agi.
114 #define XFS_AGI_UNLINKED_BUCKETS 64
116 typedef struct xfs_agi {
118 * Common allocation group header information
120 __be32 agi_magicnum; /* magic number == XFS_AGI_MAGIC */
121 __be32 agi_versionnum; /* header version == XFS_AGI_VERSION */
122 __be32 agi_seqno; /* sequence # starting from 0 */
123 __be32 agi_length; /* size in blocks of a.g. */
125 * Inode information
126 * Inodes are mapped by interpreting the inode number, so no
127 * mapping data is needed here.
129 __be32 agi_count; /* count of allocated inodes */
130 __be32 agi_root; /* root of inode btree */
131 __be32 agi_level; /* levels in inode btree */
132 __be32 agi_freecount; /* number of free inodes */
133 __be32 agi_newino; /* new inode just allocated */
134 __be32 agi_dirino; /* last directory inode chunk */
136 * Hash table of inodes which have been unlinked but are
137 * still being referenced.
139 __be32 agi_unlinked[XFS_AGI_UNLINKED_BUCKETS];
140 } xfs_agi_t;
142 #define XFS_AGI_MAGICNUM 0x00000001
143 #define XFS_AGI_VERSIONNUM 0x00000002
144 #define XFS_AGI_SEQNO 0x00000004
145 #define XFS_AGI_LENGTH 0x00000008
146 #define XFS_AGI_COUNT 0x00000010
147 #define XFS_AGI_ROOT 0x00000020
148 #define XFS_AGI_LEVEL 0x00000040
149 #define XFS_AGI_FREECOUNT 0x00000080
150 #define XFS_AGI_NEWINO 0x00000100
151 #define XFS_AGI_DIRINO 0x00000200
152 #define XFS_AGI_UNLINKED 0x00000400
153 #define XFS_AGI_NUM_BITS 11
154 #define XFS_AGI_ALL_BITS ((1 << XFS_AGI_NUM_BITS) - 1)
156 /* disk block (xfs_daddr_t) in the AG */
157 #define XFS_AGI_DADDR(mp) ((xfs_daddr_t)(2 << (mp)->m_sectbb_log))
158 #define XFS_AGI_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp))
159 #define XFS_BUF_TO_AGI(bp) ((xfs_agi_t *)((bp)->b_addr))
161 extern int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp,
162 xfs_agnumber_t agno, struct xfs_buf **bpp);
165 * The third a.g. block contains the a.g. freelist, an array
166 * of block pointers to blocks owned by the allocation btree code.
168 #define XFS_AGFL_DADDR(mp) ((xfs_daddr_t)(3 << (mp)->m_sectbb_log))
169 #define XFS_AGFL_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp))
170 #define XFS_AGFL_SIZE(mp) ((mp)->m_sb.sb_sectsize / sizeof(xfs_agblock_t))
171 #define XFS_BUF_TO_AGFL(bp) ((xfs_agfl_t *)((bp)->b_addr))
173 typedef struct xfs_agfl {
174 __be32 agfl_bno[1]; /* actually XFS_AGFL_SIZE(mp) */
175 } xfs_agfl_t;
178 * Busy block/extent entry. Indexed by a rbtree in perag to mark blocks that
179 * have been freed but whose transactions aren't committed to disk yet.
181 * Note that we use the transaction ID to record the transaction, not the
182 * transaction structure itself. See xfs_alloc_busy_insert() for details.
184 struct xfs_busy_extent {
185 struct rb_node rb_node; /* ag by-bno indexed search tree */
186 struct list_head list; /* transaction busy extent list */
187 xfs_agnumber_t agno;
188 xfs_agblock_t bno;
189 xfs_extlen_t length;
190 unsigned int flags;
191 #define XFS_ALLOC_BUSY_DISCARDED 0x01 /* undergoing a discard op. */
192 #define XFS_ALLOC_BUSY_SKIP_DISCARD 0x02 /* do not discard */
196 * Per-ag incore structure, copies of information in agf and agi,
197 * to improve the performance of allocation group selection.
199 #define XFS_PAGB_NUM_SLOTS 128
201 typedef struct xfs_perag {
202 struct xfs_mount *pag_mount; /* owner filesystem */
203 xfs_agnumber_t pag_agno; /* AG this structure belongs to */
204 atomic_t pag_ref; /* perag reference count */
205 char pagf_init; /* this agf's entry is initialized */
206 char pagi_init; /* this agi's entry is initialized */
207 char pagf_metadata; /* the agf is preferred to be metadata */
208 char pagi_inodeok; /* The agi is ok for inodes */
209 __uint8_t pagf_levels[XFS_BTNUM_AGF];
210 /* # of levels in bno & cnt btree */
211 __uint32_t pagf_flcount; /* count of blocks in freelist */
212 xfs_extlen_t pagf_freeblks; /* total free blocks */
213 xfs_extlen_t pagf_longest; /* longest free space */
214 __uint32_t pagf_btreeblks; /* # of blocks held in AGF btrees */
215 xfs_agino_t pagi_freecount; /* number of free inodes */
216 xfs_agino_t pagi_count; /* number of allocated inodes */
219 * Inode allocation search lookup optimisation.
220 * If the pagino matches, the search for new inodes
221 * doesn't need to search the near ones again straight away
223 xfs_agino_t pagl_pagino;
224 xfs_agino_t pagl_leftrec;
225 xfs_agino_t pagl_rightrec;
226 #ifdef __KERNEL__
227 spinlock_t pagb_lock; /* lock for pagb_tree */
228 struct rb_root pagb_tree; /* ordered tree of busy extents */
230 atomic_t pagf_fstrms; /* # of filestreams active in this AG */
232 spinlock_t pag_ici_lock; /* incore inode cache lock */
233 struct radix_tree_root pag_ici_root; /* incore inode cache root */
234 int pag_ici_reclaimable; /* reclaimable inodes */
235 struct mutex pag_ici_reclaim_lock; /* serialisation point */
236 unsigned long pag_ici_reclaim_cursor; /* reclaim restart point */
238 /* buffer cache index */
239 spinlock_t pag_buf_lock; /* lock for pag_buf_tree */
240 struct rb_root pag_buf_tree; /* ordered tree of active buffers */
242 /* for rcu-safe freeing */
243 struct rcu_head rcu_head;
244 #endif
245 int pagb_count; /* pagb slots in use */
246 } xfs_perag_t;
249 * tags for inode radix tree
251 #define XFS_ICI_NO_TAG (-1) /* special flag for an untagged lookup
252 in xfs_inode_ag_iterator */
253 #define XFS_ICI_RECLAIM_TAG 0 /* inode is to be reclaimed */
255 #define XFS_AG_MAXLEVELS(mp) ((mp)->m_ag_maxlevels)
256 #define XFS_MIN_FREELIST_RAW(bl,cl,mp) \
257 (MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp)))
258 #define XFS_MIN_FREELIST(a,mp) \
259 (XFS_MIN_FREELIST_RAW( \
260 be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \
261 be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp))
262 #define XFS_MIN_FREELIST_PAG(pag,mp) \
263 (XFS_MIN_FREELIST_RAW( \
264 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_BNOi], \
265 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp))
267 #define XFS_AGB_TO_FSB(mp,agno,agbno) \
268 (((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno))
269 #define XFS_FSB_TO_AGNO(mp,fsbno) \
270 ((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog))
271 #define XFS_FSB_TO_AGBNO(mp,fsbno) \
272 ((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog)))
273 #define XFS_AGB_TO_DADDR(mp,agno,agbno) \
274 ((xfs_daddr_t)XFS_FSB_TO_BB(mp, \
275 (xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno)))
276 #define XFS_AG_DADDR(mp,agno,d) (XFS_AGB_TO_DADDR(mp, agno, 0) + (d))
279 * For checking for bad ranges of xfs_daddr_t's, covering multiple
280 * allocation groups or a single xfs_daddr_t that's a superblock copy.
282 #define XFS_AG_CHECK_DADDR(mp,d,len) \
283 ((len) == 1 ? \
284 ASSERT((d) == XFS_SB_DADDR || \
285 xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \
286 ASSERT(xfs_daddr_to_agno(mp, d) == \
287 xfs_daddr_to_agno(mp, (d) + (len) - 1)))
289 #endif /* __XFS_AG_H__ */