xfs_ialloc_btree.c

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/*
 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_types.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ialloc.h"
#include "xfs_alloc.h"
#include "xfs_error.h"


STATIC int
xfs_inobt_get_minrecs(
    struct xfs_btree_cur    *cur,
    int         level)
{
    return cur->bc_mp->m_inobt_mnr[level != 0];
}

STATIC struct xfs_btree_cur *
xfs_inobt_dup_cursor(
    struct xfs_btree_cur    *cur)
{
    return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
            cur->bc_private.a.agbp, cur->bc_private.a.agno);
}

STATIC void
xfs_inobt_set_root(
    struct xfs_btree_cur    *cur,
    union xfs_btree_ptr *nptr,
    int         inc)    /* level change */
{
    struct xfs_buf      *agbp = cur->bc_private.a.agbp;
    struct xfs_agi      *agi = XFS_BUF_TO_AGI(agbp);

    agi->agi_root = nptr->s;
    be32_add_cpu(&agi->agi_level, inc);
    xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
}

STATIC int
xfs_inobt_alloc_block(
    struct xfs_btree_cur    *cur,
    union xfs_btree_ptr *start,
    union xfs_btree_ptr *new,
    int         length,
    int         *stat)
{
    xfs_alloc_arg_t     args;       /* block allocation args */
    int         error;      /* error return value */
    xfs_agblock_t       sbno = be32_to_cpu(start->s);

    XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);

    memset(&args, 0, sizeof(args));
    args.tp = cur->bc_tp;
    args.mp = cur->bc_mp;
    args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
    args.minlen = 1;
    args.maxlen = 1;
    args.prod = 1;
    args.type = XFS_ALLOCTYPE_NEAR_BNO;

    error = xfs_alloc_vextent(&args);
    if (error) {
        XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
        return error;
    }
    if (args.fsbno == NULLFSBLOCK) {
        XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
        *stat = 0;
        return 0;
    }
    ASSERT(args.len == 1);
    XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);

    new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
    *stat = 1;
    return 0;
}

STATIC int
xfs_inobt_free_block(
    struct xfs_btree_cur    *cur,
    struct xfs_buf      *bp)
{
    xfs_fsblock_t       fsbno;
    int         error;

    fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
    error = xfs_free_extent(cur->bc_tp, fsbno, 1);
    if (error)
        return error;

    xfs_trans_binval(cur->bc_tp, bp);
    return error;
}

STATIC int
xfs_inobt_get_maxrecs(
    struct xfs_btree_cur    *cur,
    int         level)
{
    return cur->bc_mp->m_inobt_mxr[level != 0];
}

STATIC void
xfs_inobt_init_key_from_rec(
    union xfs_btree_key *key,
    union xfs_btree_rec *rec)
{
    key->inobt.ir_startino = rec->inobt.ir_startino;
}

STATIC void
xfs_inobt_init_rec_from_key(
    union xfs_btree_key *key,
    union xfs_btree_rec *rec)
{
    rec->inobt.ir_startino = key->inobt.ir_startino;
}

STATIC void
xfs_inobt_init_rec_from_cur(
    struct xfs_btree_cur    *cur,
    union xfs_btree_rec *rec)
{
    rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
    rec->inobt.ir_freecount = cpu_to_be32(cur->bc_rec.i.ir_freecount);
    rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
}

/*
 * initial value of ptr for lookup
 */
STATIC void
xfs_inobt_init_ptr_from_cur(
    struct xfs_btree_cur    *cur,
    union xfs_btree_ptr *ptr)
{
    struct xfs_agi      *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);

    ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));

    ptr->s = agi->agi_root;
}

STATIC __int64_t
xfs_inobt_key_diff(
    struct xfs_btree_cur    *cur,
    union xfs_btree_key *key)
{
    return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
              cur->bc_rec.i.ir_startino;
}

#ifdef DEBUG
STATIC int
xfs_inobt_keys_inorder(
    struct xfs_btree_cur    *cur,
    union xfs_btree_key *k1,
    union xfs_btree_key *k2)
{
    return be32_to_cpu(k1->inobt.ir_startino) <
        be32_to_cpu(k2->inobt.ir_startino);
}

STATIC int
xfs_inobt_recs_inorder(
    struct xfs_btree_cur    *cur,
    union xfs_btree_rec *r1,
    union xfs_btree_rec *r2)
{
    return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
        be32_to_cpu(r2->inobt.ir_startino);
}
#endif  /* DEBUG */

static const struct xfs_btree_ops xfs_inobt_ops = {
    .rec_len        = sizeof(xfs_inobt_rec_t),
    .key_len        = sizeof(xfs_inobt_key_t),

    .dup_cursor     = xfs_inobt_dup_cursor,
    .set_root       = xfs_inobt_set_root,
    .alloc_block        = xfs_inobt_alloc_block,
    .free_block     = xfs_inobt_free_block,
    .get_minrecs        = xfs_inobt_get_minrecs,
    .get_maxrecs        = xfs_inobt_get_maxrecs,
    .init_key_from_rec  = xfs_inobt_init_key_from_rec,
    .init_rec_from_key  = xfs_inobt_init_rec_from_key,
    .init_rec_from_cur  = xfs_inobt_init_rec_from_cur,
    .init_ptr_from_cur  = xfs_inobt_init_ptr_from_cur,
    .key_diff       = xfs_inobt_key_diff,
#ifdef DEBUG
    .keys_inorder       = xfs_inobt_keys_inorder,
    .recs_inorder       = xfs_inobt_recs_inorder,
#endif
};

/*
 * Allocate a new inode btree cursor.
 */
struct xfs_btree_cur *              /* new inode btree cursor */
xfs_inobt_init_cursor(
    struct xfs_mount    *mp,        /* file system mount point */
    struct xfs_trans    *tp,        /* transaction pointer */
    struct xfs_buf      *agbp,      /* buffer for agi structure */
    xfs_agnumber_t      agno)       /* allocation group number */
{
    struct xfs_agi      *agi = XFS_BUF_TO_AGI(agbp);
    struct xfs_btree_cur    *cur;

    cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);

    cur->bc_tp = tp;
    cur->bc_mp = mp;
    cur->bc_nlevels = be32_to_cpu(agi->agi_level);
    cur->bc_btnum = XFS_BTNUM_INO;
    cur->bc_blocklog = mp->m_sb.sb_blocklog;

    cur->bc_ops = &xfs_inobt_ops;

    cur->bc_private.a.agbp = agbp;
    cur->bc_private.a.agno = agno;

    return cur;
}

/*
 * Calculate number of records in an inobt btree block.
 */
int
xfs_inobt_maxrecs(
    struct xfs_mount    *mp,
    int         blocklen,
    int         leaf)
{
    blocklen -= XFS_INOBT_BLOCK_LEN(mp);

    if (leaf)
        return blocklen / sizeof(xfs_inobt_rec_t);
    return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
}