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