fs/xfs/xfs_ialloc_btree.c

   1 /*
   2  * Copyright (c) 2000-2001,2005 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 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_shared.h"
  21 #include "xfs_format.h"
  22 #include "xfs_log_format.h"
  23 #include "xfs_trans_resv.h"
  24 #include "xfs_bit.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_mount.h"
  28 #include "xfs_inode.h"
  29 #include "xfs_btree.h"
  30 #include "xfs_ialloc.h"
  31 #include "xfs_ialloc_btree.h"
  32 #include "xfs_alloc.h"
  33 #include "xfs_error.h"
  34 #include "xfs_trace.h"
  35 #include "xfs_cksum.h"
  36 #include "xfs_trans.h"
  37
  38
  39 STATIC int
  40 xfs_inobt_get_minrecs(
  41         struct xfs_btree_cur    *cur,
  42         int                     level)
  43 {
  44         return cur->bc_mp->m_inobt_mnr[level != 0];
  45 }
  46
  47 STATIC struct xfs_btree_cur *
  48 xfs_inobt_dup_cursor(
  49         struct xfs_btree_cur    *cur)
  50 {
  51         return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
  52                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
  53                         cur->bc_btnum);
  54 }
  55
  56 STATIC void
  57 xfs_inobt_set_root(
  58         struct xfs_btree_cur    *cur,
  59         union xfs_btree_ptr     *nptr,
  60         int                     inc)    /* level change */
  61 {
  62         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  63         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
  64
  65         agi->agi_root = nptr->s;
  66         be32_add_cpu(&agi->agi_level, inc);
  67         xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
  68 }
  69
  70 STATIC int
  71 xfs_inobt_alloc_block(
  72         struct xfs_btree_cur    *cur,
  73         union xfs_btree_ptr     *start,
  74         union xfs_btree_ptr     *new,
  75         int                     length,
  76         int                     *stat)
  77 {
  78         xfs_alloc_arg_t         args;           /* block allocation args */
  79         int                     error;          /* error return value */
  80         xfs_agblock_t           sbno = be32_to_cpu(start->s);
  81
  82         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  83
  84         memset(&args, 0, sizeof(args));
  85         args.tp = cur->bc_tp;
  86         args.mp = cur->bc_mp;
  87         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
  88         args.minlen = 1;
  89         args.maxlen = 1;
  90         args.prod = 1;
  91         args.type = XFS_ALLOCTYPE_NEAR_BNO;
  92
  93         error = xfs_alloc_vextent(&args);
  94         if (error) {
  95                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  96                 return error;
  97         }
  98         if (args.fsbno == NULLFSBLOCK) {
  99                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 100                 *stat = 0;
 101                 return 0;
 102         }
 103         ASSERT(args.len == 1);
 104         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 105
 106         new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
 107         *stat = 1;
 108         return 0;
 109 }
 110
 111 STATIC int
 112 xfs_inobt_free_block(
 113         struct xfs_btree_cur    *cur,
 114         struct xfs_buf          *bp)
 115 {
 116         xfs_fsblock_t           fsbno;
 117         int                     error;
 118
 119         fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
 120         error = xfs_free_extent(cur->bc_tp, fsbno, 1);
 121         if (error)
 122                 return error;
 123
 124         xfs_trans_binval(cur->bc_tp, bp);
 125         return error;
 126 }
 127
 128 STATIC int
 129 xfs_inobt_get_maxrecs(
 130         struct xfs_btree_cur    *cur,
 131         int                     level)
 132 {
 133         return cur->bc_mp->m_inobt_mxr[level != 0];
 134 }
 135
 136 STATIC void
 137 xfs_inobt_init_key_from_rec(
 138         union xfs_btree_key     *key,
 139         union xfs_btree_rec     *rec)
 140 {
 141         key->inobt.ir_startino = rec->inobt.ir_startino;
 142 }
 143
 144 STATIC void
 145 xfs_inobt_init_rec_from_key(
 146         union xfs_btree_key     *key,
 147         union xfs_btree_rec     *rec)
 148 {
 149         rec->inobt.ir_startino = key->inobt.ir_startino;
 150 }
 151
 152 STATIC void
 153 xfs_inobt_init_rec_from_cur(
 154         struct xfs_btree_cur    *cur,
 155         union xfs_btree_rec     *rec)
 156 {
 157         rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
 158         rec->inobt.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
 159         rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
 160 }
 161
 162 /*
 163  * initial value of ptr for lookup
 164  */
 165 STATIC void
 166 xfs_inobt_init_ptr_from_cur(
 167         struct xfs_btree_cur    *cur,
 168         union xfs_btree_ptr     *ptr)
 169 {
 170         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
 171
 172         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
 173
 174         ptr->s = agi->agi_root;
 175 }
 176
 177 STATIC __int64_t
 178 xfs_inobt_key_diff(
 179         struct xfs_btree_cur    *cur,
 180         union xfs_btree_key     *key)
 181 {
 182         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
 183                           cur->bc_rec.i.ir_startino;
 184 }
 185
 186 static int
 187 xfs_inobt_verify(
 188         struct xfs_buf          *bp)
 189 {
 190         struct xfs_mount        *mp = bp->b_target->bt_mount;
 191         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 192         struct xfs_perag        *pag = bp->b_pag;
 193         unsigned int            level;
 194
 195         /*
 196          * During growfs operations, we can't verify the exact owner as the
 197          * perag is not fully initialised and hence not attached to the buffer.
 198          *
 199          * Similarly, during log recovery we will have a perag structure
 200          * attached, but the agi information will not yet have been initialised
 201          * from the on disk AGI. We don't currently use any of this information,
 202          * but beware of the landmine (i.e. need to check pag->pagi_init) if we
 203          * ever do.
 204          */
 205         switch (block->bb_magic) {
 206         case cpu_to_be32(XFS_IBT_CRC_MAGIC):
 207                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 208                         return false;
 209                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 210                         return false;
 211                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 212                         return false;
 213                 if (pag &&
 214                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 215                         return false;
 216                 /* fall through */
 217         case cpu_to_be32(XFS_IBT_MAGIC):
 218                 break;
 219         default:
 220                 return 0;
 221         }
 222
 223         /* numrecs and level verification */
 224         level = be16_to_cpu(block->bb_level);
 225         if (level >= mp->m_in_maxlevels)
 226                 return false;
 227         if (be16_to_cpu(block->bb_numrecs) > mp->m_inobt_mxr[level != 0])
 228                 return false;
 229
 230         /* sibling pointer verification */
 231         if (!block->bb_u.s.bb_leftsib ||
 232             (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
 233              block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
 234                 return false;
 235         if (!block->bb_u.s.bb_rightsib ||
 236             (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
 237              block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
 238                 return false;
 239
 240         return true;
 241 }
 242
 243 static void
 244 xfs_inobt_read_verify(
 245         struct xfs_buf  *bp)
 246 {
 247         if (!xfs_btree_sblock_verify_crc(bp))
 248                 xfs_buf_ioerror(bp, EFSBADCRC);
 249         else if (!xfs_inobt_verify(bp))
 250                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 251
 252         if (bp->b_error) {
 253                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 254                 xfs_verifier_error(bp);
 255         }
 256 }
 257
 258 static void
 259 xfs_inobt_write_verify(
 260         struct xfs_buf  *bp)
 261 {
 262         if (!xfs_inobt_verify(bp)) {
 263                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 264                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 265                 xfs_verifier_error(bp);
 266                 return;
 267         }
 268         xfs_btree_sblock_calc_crc(bp);
 269
 270 }
 271
 272 const struct xfs_buf_ops xfs_inobt_buf_ops = {
 273         .verify_read = xfs_inobt_read_verify,
 274         .verify_write = xfs_inobt_write_verify,
 275 };
 276
 277 #if defined(DEBUG) || defined(XFS_WARN)
 278 STATIC int
 279 xfs_inobt_keys_inorder(
 280         struct xfs_btree_cur    *cur,
 281         union xfs_btree_key     *k1,
 282         union xfs_btree_key     *k2)
 283 {
 284         return be32_to_cpu(k1->inobt.ir_startino) <
 285                 be32_to_cpu(k2->inobt.ir_startino);
 286 }
 287
 288 STATIC int
 289 xfs_inobt_recs_inorder(
 290         struct xfs_btree_cur    *cur,
 291         union xfs_btree_rec     *r1,
 292         union xfs_btree_rec     *r2)
 293 {
 294         return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
 295                 be32_to_cpu(r2->inobt.ir_startino);
 296 }
 297 #endif  /* DEBUG */
 298
 299 static const struct xfs_btree_ops xfs_inobt_ops = {
 300         .rec_len                = sizeof(xfs_inobt_rec_t),
 301         .key_len                = sizeof(xfs_inobt_key_t),
 302
 303         .dup_cursor             = xfs_inobt_dup_cursor,
 304         .set_root               = xfs_inobt_set_root,
 305         .alloc_block            = xfs_inobt_alloc_block,
 306         .free_block             = xfs_inobt_free_block,
 307         .get_minrecs            = xfs_inobt_get_minrecs,
 308         .get_maxrecs            = xfs_inobt_get_maxrecs,
 309         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
 310         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
 311         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
 312         .init_ptr_from_cur      = xfs_inobt_init_ptr_from_cur,
 313         .key_diff               = xfs_inobt_key_diff,
 314         .buf_ops                = &xfs_inobt_buf_ops,
 315 #if defined(DEBUG) || defined(XFS_WARN)
 316         .keys_inorder           = xfs_inobt_keys_inorder,
 317         .recs_inorder           = xfs_inobt_recs_inorder,
 318 #endif
 319 };
 320
 321 /*
 322  * Allocate a new inode btree cursor.
 323  */
 324 struct xfs_btree_cur *                          /* new inode btree cursor */
 325 xfs_inobt_init_cursor(
 326         struct xfs_mount        *mp,            /* file system mount point */
 327         struct xfs_trans        *tp,            /* transaction pointer */
 328         struct xfs_buf          *agbp,          /* buffer for agi structure */
 329         xfs_agnumber_t          agno,           /* allocation group number */
 330         xfs_btnum_t             btnum)          /* ialloc or free ino btree */
 331 {
 332         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
 333         struct xfs_btree_cur    *cur;
 334
 335         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 336
 337         cur->bc_tp = tp;
 338         cur->bc_mp = mp;
 339         cur->bc_nlevels = be32_to_cpu(agi->agi_level);
 340         cur->bc_btnum = btnum;
 341         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 342
 343         cur->bc_ops = &xfs_inobt_ops;
 344         if (xfs_sb_version_hascrc(&mp->m_sb))
 345                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 346
 347         cur->bc_private.a.agbp = agbp;
 348         cur->bc_private.a.agno = agno;
 349
 350         return cur;
 351 }
 352
 353 /*
 354  * Calculate number of records in an inobt btree block.
 355  */
 356 int
 357 xfs_inobt_maxrecs(
 358         struct xfs_mount        *mp,
 359         int                     blocklen,
 360         int                     leaf)
 361 {
 362         blocklen -= XFS_INOBT_BLOCK_LEN(mp);
 363
 364         if (leaf)
 365                 return blocklen / sizeof(xfs_inobt_rec_t);
 366         return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
 367 }