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 27 struct xfs_buf; 28 struct xfs_mount; 29 struct 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 51 typedef 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 __be32 agf_btreeblks; /* # of blocks held in AGF btrees */ 72 } xfs_agf_t; 73 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) 88 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" } 102 103 /* 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 *)XFS_BUF_PTR(bp)) 107 108 extern int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp, 109 xfs_agnumber_t agno, int flags, struct xfs_buf **bpp); 110 111 /* 112 * Size of the unlinked inode hash table in the agi. 113 */ 114 #define XFS_AGI_UNLINKED_BUCKETS 64 115 116 typedef struct xfs_agi { 117 /* 118 * Common allocation group header information 119 */ 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. */ 124 /* 125 * Inode information 126 * Inodes are mapped by interpreting the inode number, so no 127 * mapping data is needed here. 128 */ 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 */ 135 /* 136 * Hash table of inodes which have been unlinked but are 137 * still being referenced. 138 */ 139 __be32 agi_unlinked[XFS_AGI_UNLINKED_BUCKETS]; 140 } xfs_agi_t; 141 142 #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) 155 156 /* 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 *)XFS_BUF_PTR(bp)) 160 161 extern int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp, 162 xfs_agnumber_t agno, struct xfs_buf **bpp); 163 164 /* 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. 167 */ 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 *)XFS_BUF_PTR(bp)) 172 173 typedef struct xfs_agfl { 174 __be32 agfl_bno[1]; /* actually XFS_AGFL_SIZE(mp) */ 175 } xfs_agfl_t; 176 177 /* 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. 180 * 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. 183 */ 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 xlog_tid_t tid; /* transaction that created this */ 191 }; 192 193 /* 194 * Per-ag incore structure, copies of information in agf and agi, 195 * to improve the performance of allocation group selection. 196 */ 197 #define XFS_PAGB_NUM_SLOTS 128 198 199 typedef struct xfs_perag { 200 struct xfs_mount *pag_mount; /* owner filesystem */ 201 xfs_agnumber_t pag_agno; /* AG this structure belongs to */ 202 atomic_t pag_ref; /* perag reference count */ 203 char pagf_init; /* this agf's entry is initialized */ 204 char pagi_init; /* this agi's entry is initialized */ 205 char pagf_metadata; /* the agf is preferred to be metadata */ 206 char pagi_inodeok; /* The agi is ok for inodes */ 207 __uint8_t pagf_levels[XFS_BTNUM_AGF]; 208 /* # of levels in bno & cnt btree */ 209 __uint32_t pagf_flcount; /* count of blocks in freelist */ 210 xfs_extlen_t pagf_freeblks; /* total free blocks */ 211 xfs_extlen_t pagf_longest; /* longest free space */ 212 __uint32_t pagf_btreeblks; /* # of blocks held in AGF btrees */ 213 xfs_agino_t pagi_freecount; /* number of free inodes */ 214 xfs_agino_t pagi_count; /* number of allocated inodes */ 215 216 /* 217 * Inode allocation search lookup optimisation. 218 * If the pagino matches, the search for new inodes 219 * doesn't need to search the near ones again straight away 220 */ 221 xfs_agino_t pagl_pagino; 222 xfs_agino_t pagl_leftrec; 223 xfs_agino_t pagl_rightrec; 224 #ifdef __KERNEL__ 225 spinlock_t pagb_lock; /* lock for pagb_tree */ 226 struct rb_root pagb_tree; /* ordered tree of busy extents */ 227 228 atomic_t pagf_fstrms; /* # of filestreams active in this AG */ 229 230 spinlock_t pag_ici_lock; /* incore inode cache lock */ 231 struct radix_tree_root pag_ici_root; /* incore inode cache root */ 232 int pag_ici_reclaimable; /* reclaimable inodes */ 233 struct mutex pag_ici_reclaim_lock; /* serialisation point */ 234 unsigned long pag_ici_reclaim_cursor; /* reclaim restart point */ 235 236 /* buffer cache index */ 237 spinlock_t pag_buf_lock; /* lock for pag_buf_tree */ 238 struct rb_root pag_buf_tree; /* ordered tree of active buffers */ 239 240 /* for rcu-safe freeing */ 241 struct rcu_head rcu_head; 242 #endif 243 int pagb_count; /* pagb slots in use */ 244 } xfs_perag_t; 245 246 /* 247 * tags for inode radix tree 248 */ 249 #define XFS_ICI_NO_TAG (-1) /* special flag for an untagged lookup 250 in xfs_inode_ag_iterator */ 251 #define XFS_ICI_RECLAIM_TAG 0 /* inode is to be reclaimed */ 252 253 #define XFS_AG_MAXLEVELS(mp) ((mp)->m_ag_maxlevels) 254 #define XFS_MIN_FREELIST_RAW(bl,cl,mp) \ 255 (MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp))) 256 #define XFS_MIN_FREELIST(a,mp) \ 257 (XFS_MIN_FREELIST_RAW( \ 258 be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \ 259 be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp)) 260 #define XFS_MIN_FREELIST_PAG(pag,mp) \ 261 (XFS_MIN_FREELIST_RAW( \ 262 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_BNOi], \ 263 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp)) 264 265 #define XFS_AGB_TO_FSB(mp,agno,agbno) \ 266 (((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno)) 267 #define XFS_FSB_TO_AGNO(mp,fsbno) \ 268 ((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog)) 269 #define XFS_FSB_TO_AGBNO(mp,fsbno) \ 270 ((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog))) 271 #define XFS_AGB_TO_DADDR(mp,agno,agbno) \ 272 ((xfs_daddr_t)XFS_FSB_TO_BB(mp, \ 273 (xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno))) 274 #define XFS_AG_DADDR(mp,agno,d) (XFS_AGB_TO_DADDR(mp, agno, 0) + (d)) 275 276 /* 277 * For checking for bad ranges of xfs_daddr_t's, covering multiple 278 * allocation groups or a single xfs_daddr_t that's a superblock copy. 279 */ 280 #define XFS_AG_CHECK_DADDR(mp,d,len) \ 281 ((len) == 1 ? \ 282 ASSERT((d) == XFS_SB_DADDR || \ 283 xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \ 284 ASSERT(xfs_daddr_to_agno(mp, d) == \ 285 xfs_daddr_to_agno(mp, (d) + (len) - 1))) 286 287 #endif /* __XFS_AG_H__ */ 288