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_AGFL_MAGIC 0x5841464c /* 'XAFL' */ 34 #define XFS_AGF_VERSION 1 35 #define XFS_AGI_VERSION 1 36 37 #define XFS_AGF_GOOD_VERSION(v) ((v) == XFS_AGF_VERSION) 38 #define XFS_AGI_GOOD_VERSION(v) ((v) == XFS_AGI_VERSION) 39 40 /* 41 * Btree number 0 is bno, 1 is cnt. This value gives the size of the 42 * arrays below. 43 */ 44 #define XFS_BTNUM_AGF ((int)XFS_BTNUM_CNTi + 1) 45 46 /* 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. 50 */ 51 52 typedef struct xfs_agf { 53 /* 54 * Common allocation group header information 55 */ 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. */ 60 /* 61 * Freespace information 62 */ 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 */ 67 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 */ 72 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 */ 76 77 /* 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. 81 */ 82 __be64 agf_spare64[16]; 83 84 /* unlogged fields, written during buffer writeback. */ 85 __be64 agf_lsn; /* last write sequence */ 86 __be32 agf_crc; /* crc of agf sector */ 87 __be32 agf_spare2; 88 89 /* structure must be padded to 64 bit alignment */ 90 } xfs_agf_t; 91 92 #define XFS_AGF_CRC_OFF offsetof(struct xfs_agf, agf_crc) 93 94 #define XFS_AGF_MAGICNUM 0x00000001 95 #define XFS_AGF_VERSIONNUM 0x00000002 96 #define XFS_AGF_SEQNO 0x00000004 97 #define XFS_AGF_LENGTH 0x00000008 98 #define XFS_AGF_ROOTS 0x00000010 99 #define XFS_AGF_LEVELS 0x00000020 100 #define XFS_AGF_FLFIRST 0x00000040 101 #define XFS_AGF_FLLAST 0x00000080 102 #define XFS_AGF_FLCOUNT 0x00000100 103 #define XFS_AGF_FREEBLKS 0x00000200 104 #define XFS_AGF_LONGEST 0x00000400 105 #define XFS_AGF_BTREEBLKS 0x00000800 106 #define XFS_AGF_UUID 0x00001000 107 #define XFS_AGF_NUM_BITS 13 108 #define XFS_AGF_ALL_BITS ((1 << XFS_AGF_NUM_BITS) - 1) 109 110 #define XFS_AGF_FLAGS \ 111 { XFS_AGF_MAGICNUM, "MAGICNUM" }, \ 112 { XFS_AGF_VERSIONNUM, "VERSIONNUM" }, \ 113 { XFS_AGF_SEQNO, "SEQNO" }, \ 114 { XFS_AGF_LENGTH, "LENGTH" }, \ 115 { XFS_AGF_ROOTS, "ROOTS" }, \ 116 { XFS_AGF_LEVELS, "LEVELS" }, \ 117 { XFS_AGF_FLFIRST, "FLFIRST" }, \ 118 { XFS_AGF_FLLAST, "FLLAST" }, \ 119 { XFS_AGF_FLCOUNT, "FLCOUNT" }, \ 120 { XFS_AGF_FREEBLKS, "FREEBLKS" }, \ 121 { XFS_AGF_LONGEST, "LONGEST" }, \ 122 { XFS_AGF_BTREEBLKS, "BTREEBLKS" }, \ 123 { XFS_AGF_UUID, "UUID" } 124 125 /* disk block (xfs_daddr_t) in the AG */ 126 #define XFS_AGF_DADDR(mp) ((xfs_daddr_t)(1 << (mp)->m_sectbb_log)) 127 #define XFS_AGF_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGF_DADDR(mp)) 128 #define XFS_BUF_TO_AGF(bp) ((xfs_agf_t *)((bp)->b_addr)) 129 130 extern int xfs_read_agf(struct xfs_mount *mp, struct xfs_trans *tp, 131 xfs_agnumber_t agno, int flags, struct xfs_buf **bpp); 132 133 /* 134 * Size of the unlinked inode hash table in the agi. 135 */ 136 #define XFS_AGI_UNLINKED_BUCKETS 64 137 138 typedef struct xfs_agi { 139 /* 140 * Common allocation group header information 141 */ 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. */ 146 /* 147 * Inode information 148 * Inodes are mapped by interpreting the inode number, so no 149 * mapping data is needed here. 150 */ 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 */ 155 156 __be32 agi_newino; /* new inode just allocated */ 157 __be32 agi_dirino; /* last directory inode chunk */ 158 /* 159 * Hash table of inodes which have been unlinked but are 160 * still being referenced. 161 */ 162 __be32 agi_unlinked[XFS_AGI_UNLINKED_BUCKETS]; 163 /* 164 * This marks the end of logging region 1 and start of logging region 2. 165 */ 166 uuid_t agi_uuid; /* uuid of filesystem */ 167 __be32 agi_crc; /* crc of agi sector */ 168 __be32 agi_pad32; 169 __be64 agi_lsn; /* last write sequence */ 170 171 __be32 agi_free_root; /* root of the free inode btree */ 172 __be32 agi_free_level;/* levels in free inode btree */ 173 174 /* structure must be padded to 64 bit alignment */ 175 } xfs_agi_t; 176 177 #define XFS_AGI_CRC_OFF offsetof(struct xfs_agi, agi_crc) 178 179 #define XFS_AGI_MAGICNUM (1 << 0) 180 #define XFS_AGI_VERSIONNUM (1 << 1) 181 #define XFS_AGI_SEQNO (1 << 2) 182 #define XFS_AGI_LENGTH (1 << 3) 183 #define XFS_AGI_COUNT (1 << 4) 184 #define XFS_AGI_ROOT (1 << 5) 185 #define XFS_AGI_LEVEL (1 << 6) 186 #define XFS_AGI_FREECOUNT (1 << 7) 187 #define XFS_AGI_NEWINO (1 << 8) 188 #define XFS_AGI_DIRINO (1 << 9) 189 #define XFS_AGI_UNLINKED (1 << 10) 190 #define XFS_AGI_NUM_BITS_R1 11 /* end of the 1st agi logging region */ 191 #define XFS_AGI_ALL_BITS_R1 ((1 << XFS_AGI_NUM_BITS_R1) - 1) 192 #define XFS_AGI_FREE_ROOT (1 << 11) 193 #define XFS_AGI_FREE_LEVEL (1 << 12) 194 #define XFS_AGI_NUM_BITS_R2 13 195 196 /* disk block (xfs_daddr_t) in the AG */ 197 #define XFS_AGI_DADDR(mp) ((xfs_daddr_t)(2 << (mp)->m_sectbb_log)) 198 #define XFS_AGI_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGI_DADDR(mp)) 199 #define XFS_BUF_TO_AGI(bp) ((xfs_agi_t *)((bp)->b_addr)) 200 201 extern int xfs_read_agi(struct xfs_mount *mp, struct xfs_trans *tp, 202 xfs_agnumber_t agno, struct xfs_buf **bpp); 203 204 /* 205 * The third a.g. block contains the a.g. freelist, an array 206 * of block pointers to blocks owned by the allocation btree code. 207 */ 208 #define XFS_AGFL_DADDR(mp) ((xfs_daddr_t)(3 << (mp)->m_sectbb_log)) 209 #define XFS_AGFL_BLOCK(mp) XFS_HDR_BLOCK(mp, XFS_AGFL_DADDR(mp)) 210 #define XFS_BUF_TO_AGFL(bp) ((xfs_agfl_t *)((bp)->b_addr)) 211 212 #define XFS_BUF_TO_AGFL_BNO(mp, bp) \ 213 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \ 214 &(XFS_BUF_TO_AGFL(bp)->agfl_bno[0]) : \ 215 (__be32 *)(bp)->b_addr) 216 217 /* 218 * Size of the AGFL. For CRC-enabled filesystes we steal a couple of 219 * slots in the beginning of the block for a proper header with the 220 * location information and CRC. 221 */ 222 #define XFS_AGFL_SIZE(mp) \ 223 (((mp)->m_sb.sb_sectsize - \ 224 (xfs_sb_version_hascrc(&((mp)->m_sb)) ? \ 225 sizeof(struct xfs_agfl) : 0)) / \ 226 sizeof(xfs_agblock_t)) 227 228 typedef struct xfs_agfl { 229 __be32 agfl_magicnum; 230 __be32 agfl_seqno; 231 uuid_t agfl_uuid; 232 __be64 agfl_lsn; 233 __be32 agfl_crc; 234 __be32 agfl_bno[]; /* actually XFS_AGFL_SIZE(mp) */ 235 } xfs_agfl_t; 236 237 #define XFS_AGFL_CRC_OFF offsetof(struct xfs_agfl, agfl_crc) 238 239 /* 240 * tags for inode radix tree 241 */ 242 #define XFS_ICI_NO_TAG (-1) /* special flag for an untagged lookup 243 in xfs_inode_ag_iterator */ 244 #define XFS_ICI_RECLAIM_TAG 0 /* inode is to be reclaimed */ 245 #define XFS_ICI_EOFBLOCKS_TAG 1 /* inode has blocks beyond EOF */ 246 247 #define XFS_AG_MAXLEVELS(mp) ((mp)->m_ag_maxlevels) 248 #define XFS_MIN_FREELIST_RAW(bl,cl,mp) \ 249 (MIN(bl + 1, XFS_AG_MAXLEVELS(mp)) + MIN(cl + 1, XFS_AG_MAXLEVELS(mp))) 250 #define XFS_MIN_FREELIST(a,mp) \ 251 (XFS_MIN_FREELIST_RAW( \ 252 be32_to_cpu((a)->agf_levels[XFS_BTNUM_BNOi]), \ 253 be32_to_cpu((a)->agf_levels[XFS_BTNUM_CNTi]), mp)) 254 #define XFS_MIN_FREELIST_PAG(pag,mp) \ 255 (XFS_MIN_FREELIST_RAW( \ 256 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_BNOi], \ 257 (unsigned int)(pag)->pagf_levels[XFS_BTNUM_CNTi], mp)) 258 259 #define XFS_AGB_TO_FSB(mp,agno,agbno) \ 260 (((xfs_fsblock_t)(agno) << (mp)->m_sb.sb_agblklog) | (agbno)) 261 #define XFS_FSB_TO_AGNO(mp,fsbno) \ 262 ((xfs_agnumber_t)((fsbno) >> (mp)->m_sb.sb_agblklog)) 263 #define XFS_FSB_TO_AGBNO(mp,fsbno) \ 264 ((xfs_agblock_t)((fsbno) & xfs_mask32lo((mp)->m_sb.sb_agblklog))) 265 #define XFS_AGB_TO_DADDR(mp,agno,agbno) \ 266 ((xfs_daddr_t)XFS_FSB_TO_BB(mp, \ 267 (xfs_fsblock_t)(agno) * (mp)->m_sb.sb_agblocks + (agbno))) 268 #define XFS_AG_DADDR(mp,agno,d) (XFS_AGB_TO_DADDR(mp, agno, 0) + (d)) 269 270 /* 271 * For checking for bad ranges of xfs_daddr_t's, covering multiple 272 * allocation groups or a single xfs_daddr_t that's a superblock copy. 273 */ 274 #define XFS_AG_CHECK_DADDR(mp,d,len) \ 275 ((len) == 1 ? \ 276 ASSERT((d) == XFS_SB_DADDR || \ 277 xfs_daddr_to_agbno(mp, d) != XFS_SB_DADDR) : \ 278 ASSERT(xfs_daddr_to_agno(mp, d) == \ 279 xfs_daddr_to_agno(mp, (d) + (len) - 1))) 280 281 #endif /* __XFS_AG_H__ */ 282