linux/fs/xfs/xfs_alloc_btree.c
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   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_types.h"
  21#include "xfs_log.h"
  22#include "xfs_trans.h"
  23#include "xfs_sb.h"
  24#include "xfs_ag.h"
  25#include "xfs_mount.h"
  26#include "xfs_bmap_btree.h"
  27#include "xfs_alloc_btree.h"
  28#include "xfs_ialloc_btree.h"
  29#include "xfs_dinode.h"
  30#include "xfs_inode.h"
  31#include "xfs_btree.h"
  32#include "xfs_alloc.h"
  33#include "xfs_extent_busy.h"
  34#include "xfs_error.h"
  35#include "xfs_trace.h"
  36
  37
  38STATIC struct xfs_btree_cur *
  39xfs_allocbt_dup_cursor(
  40        struct xfs_btree_cur    *cur)
  41{
  42        return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
  43                        cur->bc_private.a.agbp, cur->bc_private.a.agno,
  44                        cur->bc_btnum);
  45}
  46
  47STATIC void
  48xfs_allocbt_set_root(
  49        struct xfs_btree_cur    *cur,
  50        union xfs_btree_ptr     *ptr,
  51        int                     inc)
  52{
  53        struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  54        struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
  55        xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
  56        int                     btnum = cur->bc_btnum;
  57        struct xfs_perag        *pag = xfs_perag_get(cur->bc_mp, seqno);
  58
  59        ASSERT(ptr->s != 0);
  60
  61        agf->agf_roots[btnum] = ptr->s;
  62        be32_add_cpu(&agf->agf_levels[btnum], inc);
  63        pag->pagf_levels[btnum] += inc;
  64        xfs_perag_put(pag);
  65
  66        xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
  67}
  68
  69STATIC int
  70xfs_allocbt_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        int                     error;
  78        xfs_agblock_t           bno;
  79
  80        XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  81
  82        /* Allocate the new block from the freelist. If we can't, give up.  */
  83        error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  84                                       &bno, 1);
  85        if (error) {
  86                XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  87                return error;
  88        }
  89
  90        if (bno == NULLAGBLOCK) {
  91                XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  92                *stat = 0;
  93                return 0;
  94        }
  95
  96        xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
  97
  98        xfs_trans_agbtree_delta(cur->bc_tp, 1);
  99        new->s = cpu_to_be32(bno);
 100
 101        XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 102        *stat = 1;
 103        return 0;
 104}
 105
 106STATIC int
 107xfs_allocbt_free_block(
 108        struct xfs_btree_cur    *cur,
 109        struct xfs_buf          *bp)
 110{
 111        struct xfs_buf          *agbp = cur->bc_private.a.agbp;
 112        struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 113        xfs_agblock_t           bno;
 114        int                     error;
 115
 116        bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
 117        error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
 118        if (error)
 119                return error;
 120
 121        xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
 122                              XFS_EXTENT_BUSY_SKIP_DISCARD);
 123        xfs_trans_agbtree_delta(cur->bc_tp, -1);
 124        return 0;
 125}
 126
 127/*
 128 * Update the longest extent in the AGF
 129 */
 130STATIC void
 131xfs_allocbt_update_lastrec(
 132        struct xfs_btree_cur    *cur,
 133        struct xfs_btree_block  *block,
 134        union xfs_btree_rec     *rec,
 135        int                     ptr,
 136        int                     reason)
 137{
 138        struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 139        xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 140        struct xfs_perag        *pag;
 141        __be32                  len;
 142        int                     numrecs;
 143
 144        ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 145
 146        switch (reason) {
 147        case LASTREC_UPDATE:
 148                /*
 149                 * If this is the last leaf block and it's the last record,
 150                 * then update the size of the longest extent in the AG.
 151                 */
 152                if (ptr != xfs_btree_get_numrecs(block))
 153                        return;
 154                len = rec->alloc.ar_blockcount;
 155                break;
 156        case LASTREC_INSREC:
 157                if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 158                    be32_to_cpu(agf->agf_longest))
 159                        return;
 160                len = rec->alloc.ar_blockcount;
 161                break;
 162        case LASTREC_DELREC:
 163                numrecs = xfs_btree_get_numrecs(block);
 164                if (ptr <= numrecs)
 165                        return;
 166                ASSERT(ptr == numrecs + 1);
 167
 168                if (numrecs) {
 169                        xfs_alloc_rec_t *rrp;
 170
 171                        rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 172                        len = rrp->ar_blockcount;
 173                } else {
 174                        len = 0;
 175                }
 176
 177                break;
 178        default:
 179                ASSERT(0);
 180                return;
 181        }
 182
 183        agf->agf_longest = len;
 184        pag = xfs_perag_get(cur->bc_mp, seqno);
 185        pag->pagf_longest = be32_to_cpu(len);
 186        xfs_perag_put(pag);
 187        xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 188}
 189
 190STATIC int
 191xfs_allocbt_get_minrecs(
 192        struct xfs_btree_cur    *cur,
 193        int                     level)
 194{
 195        return cur->bc_mp->m_alloc_mnr[level != 0];
 196}
 197
 198STATIC int
 199xfs_allocbt_get_maxrecs(
 200        struct xfs_btree_cur    *cur,
 201        int                     level)
 202{
 203        return cur->bc_mp->m_alloc_mxr[level != 0];
 204}
 205
 206STATIC void
 207xfs_allocbt_init_key_from_rec(
 208        union xfs_btree_key     *key,
 209        union xfs_btree_rec     *rec)
 210{
 211        ASSERT(rec->alloc.ar_startblock != 0);
 212
 213        key->alloc.ar_startblock = rec->alloc.ar_startblock;
 214        key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 215}
 216
 217STATIC void
 218xfs_allocbt_init_rec_from_key(
 219        union xfs_btree_key     *key,
 220        union xfs_btree_rec     *rec)
 221{
 222        ASSERT(key->alloc.ar_startblock != 0);
 223
 224        rec->alloc.ar_startblock = key->alloc.ar_startblock;
 225        rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
 226}
 227
 228STATIC void
 229xfs_allocbt_init_rec_from_cur(
 230        struct xfs_btree_cur    *cur,
 231        union xfs_btree_rec     *rec)
 232{
 233        ASSERT(cur->bc_rec.a.ar_startblock != 0);
 234
 235        rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 236        rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 237}
 238
 239STATIC void
 240xfs_allocbt_init_ptr_from_cur(
 241        struct xfs_btree_cur    *cur,
 242        union xfs_btree_ptr     *ptr)
 243{
 244        struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 245
 246        ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 247        ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 248
 249        ptr->s = agf->agf_roots[cur->bc_btnum];
 250}
 251
 252STATIC __int64_t
 253xfs_allocbt_key_diff(
 254        struct xfs_btree_cur    *cur,
 255        union xfs_btree_key     *key)
 256{
 257        xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 258        xfs_alloc_key_t         *kp = &key->alloc;
 259        __int64_t               diff;
 260
 261        if (cur->bc_btnum == XFS_BTNUM_BNO) {
 262                return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 263                                rec->ar_startblock;
 264        }
 265
 266        diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 267        if (diff)
 268                return diff;
 269
 270        return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 271}
 272
 273#ifdef DEBUG
 274STATIC int
 275xfs_allocbt_keys_inorder(
 276        struct xfs_btree_cur    *cur,
 277        union xfs_btree_key     *k1,
 278        union xfs_btree_key     *k2)
 279{
 280        if (cur->bc_btnum == XFS_BTNUM_BNO) {
 281                return be32_to_cpu(k1->alloc.ar_startblock) <
 282                       be32_to_cpu(k2->alloc.ar_startblock);
 283        } else {
 284                return be32_to_cpu(k1->alloc.ar_blockcount) <
 285                        be32_to_cpu(k2->alloc.ar_blockcount) ||
 286                        (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 287                         be32_to_cpu(k1->alloc.ar_startblock) <
 288                         be32_to_cpu(k2->alloc.ar_startblock));
 289        }
 290}
 291
 292STATIC int
 293xfs_allocbt_recs_inorder(
 294        struct xfs_btree_cur    *cur,
 295        union xfs_btree_rec     *r1,
 296        union xfs_btree_rec     *r2)
 297{
 298        if (cur->bc_btnum == XFS_BTNUM_BNO) {
 299                return be32_to_cpu(r1->alloc.ar_startblock) +
 300                        be32_to_cpu(r1->alloc.ar_blockcount) <=
 301                        be32_to_cpu(r2->alloc.ar_startblock);
 302        } else {
 303                return be32_to_cpu(r1->alloc.ar_blockcount) <
 304                        be32_to_cpu(r2->alloc.ar_blockcount) ||
 305                        (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 306                         be32_to_cpu(r1->alloc.ar_startblock) <
 307                         be32_to_cpu(r2->alloc.ar_startblock));
 308        }
 309}
 310#endif  /* DEBUG */
 311
 312static const struct xfs_btree_ops xfs_allocbt_ops = {
 313        .rec_len                = sizeof(xfs_alloc_rec_t),
 314        .key_len                = sizeof(xfs_alloc_key_t),
 315
 316        .dup_cursor             = xfs_allocbt_dup_cursor,
 317        .set_root               = xfs_allocbt_set_root,
 318        .alloc_block            = xfs_allocbt_alloc_block,
 319        .free_block             = xfs_allocbt_free_block,
 320        .update_lastrec         = xfs_allocbt_update_lastrec,
 321        .get_minrecs            = xfs_allocbt_get_minrecs,
 322        .get_maxrecs            = xfs_allocbt_get_maxrecs,
 323        .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 324        .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
 325        .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 326        .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 327        .key_diff               = xfs_allocbt_key_diff,
 328#ifdef DEBUG
 329        .keys_inorder           = xfs_allocbt_keys_inorder,
 330        .recs_inorder           = xfs_allocbt_recs_inorder,
 331#endif
 332};
 333
 334/*
 335 * Allocate a new allocation btree cursor.
 336 */
 337struct xfs_btree_cur *                  /* new alloc btree cursor */
 338xfs_allocbt_init_cursor(
 339        struct xfs_mount        *mp,            /* file system mount point */
 340        struct xfs_trans        *tp,            /* transaction pointer */
 341        struct xfs_buf          *agbp,          /* buffer for agf structure */
 342        xfs_agnumber_t          agno,           /* allocation group number */
 343        xfs_btnum_t             btnum)          /* btree identifier */
 344{
 345        struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 346        struct xfs_btree_cur    *cur;
 347
 348        ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 349
 350        cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 351
 352        cur->bc_tp = tp;
 353        cur->bc_mp = mp;
 354        cur->bc_btnum = btnum;
 355        cur->bc_blocklog = mp->m_sb.sb_blocklog;
 356        cur->bc_ops = &xfs_allocbt_ops;
 357
 358        if (btnum == XFS_BTNUM_CNT) {
 359                cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
 360                cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 361        } else {
 362                cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
 363        }
 364
 365        cur->bc_private.a.agbp = agbp;
 366        cur->bc_private.a.agno = agno;
 367
 368        return cur;
 369}
 370
 371/*
 372 * Calculate number of records in an alloc btree block.
 373 */
 374int
 375xfs_allocbt_maxrecs(
 376        struct xfs_mount        *mp,
 377        int                     blocklen,
 378        int                     leaf)
 379{
 380        blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 381
 382        if (leaf)
 383                return blocklen / sizeof(xfs_alloc_rec_t);
 384        return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 385}
 386
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