xfs_attr_leaf.c

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/*
 * Copyright (c) 2000-2005 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_da_btree.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_alloc.h"
#include "xfs_btree.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_inode_item.h"
#include "xfs_bmap.h"
#include "xfs_attr.h"
#include "xfs_attr_leaf.h"
#include "xfs_error.h"
#include "xfs_trace.h"

/*
 * xfs_attr_leaf.c
 *
 * Routines to implement leaf blocks of attributes as Btrees of hashed names.
 */

/*========================================================================
 * Function prototypes for the kernel.
 *========================================================================*/

/*
 * Routines used for growing the Btree.
 */
STATIC int xfs_attr_leaf_create(xfs_da_args_t *args, xfs_dablk_t which_block,
                struct xfs_buf **bpp);
STATIC int xfs_attr_leaf_add_work(struct xfs_buf *leaf_buffer,
                  xfs_da_args_t *args, int freemap_index);
STATIC void xfs_attr_leaf_compact(xfs_trans_t *tp, struct xfs_buf *leaf_buffer);
STATIC void xfs_attr_leaf_rebalance(xfs_da_state_t *state,
                           xfs_da_state_blk_t *blk1,
                           xfs_da_state_blk_t *blk2);
STATIC int xfs_attr_leaf_figure_balance(xfs_da_state_t *state,
                       xfs_da_state_blk_t *leaf_blk_1,
                       xfs_da_state_blk_t *leaf_blk_2,
                       int *number_entries_in_blk1,
                       int *number_usedbytes_in_blk1);

/*
 * Routines used for shrinking the Btree.
 */
STATIC int xfs_attr_node_inactive(xfs_trans_t **trans, xfs_inode_t *dp,
                  struct xfs_buf *bp, int level);
STATIC int xfs_attr_leaf_inactive(xfs_trans_t **trans, xfs_inode_t *dp,
                  struct xfs_buf *bp);
STATIC int xfs_attr_leaf_freextent(xfs_trans_t **trans, xfs_inode_t *dp,
                   xfs_dablk_t blkno, int blkcnt);

/*
 * Utility routines.
 */
STATIC void xfs_attr_leaf_moveents(xfs_attr_leafblock_t *src_leaf,
                     int src_start,
                     xfs_attr_leafblock_t *dst_leaf,
                     int dst_start, int move_count,
                     xfs_mount_t *mp);
STATIC int xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index);

/*========================================================================
 * Namespace helper routines
 *========================================================================*/

/*
 * If namespace bits don't match return 0.
 * If all match then return 1.
 */
STATIC int
xfs_attr_namesp_match(int arg_flags, int ondisk_flags)
{
    return XFS_ATTR_NSP_ONDISK(ondisk_flags) == XFS_ATTR_NSP_ARGS_TO_ONDISK(arg_flags);
}


/*========================================================================
 * External routines when attribute fork size < XFS_LITINO(mp).
 *========================================================================*/

/*
 * Query whether the requested number of additional bytes of extended
 * attribute space will be able to fit inline.
 *
 * Returns zero if not, else the di_forkoff fork offset to be used in the
 * literal area for attribute data once the new bytes have been added.
 *
 * di_forkoff must be 8 byte aligned, hence is stored as a >>3 value;
 * special case for dev/uuid inodes, they have fixed size data forks.
 */
int
xfs_attr_shortform_bytesfit(xfs_inode_t *dp, int bytes)
{
    int offset;
    int minforkoff; /* lower limit on valid forkoff locations */
    int maxforkoff; /* upper limit on valid forkoff locations */
    int dsize;
    xfs_mount_t *mp = dp->i_mount;

    offset = (XFS_LITINO(mp) - bytes) >> 3; /* rounded down */

    switch (dp->i_d.di_format) {
    case XFS_DINODE_FMT_DEV:
        minforkoff = roundup(sizeof(xfs_dev_t), 8) >> 3;
        return (offset >= minforkoff) ? minforkoff : 0;
    case XFS_DINODE_FMT_UUID:
        minforkoff = roundup(sizeof(uuid_t), 8) >> 3;
        return (offset >= minforkoff) ? minforkoff : 0;
    }

    /*
     * If the requested numbers of bytes is smaller or equal to the
     * current attribute fork size we can always proceed.
     *
     * Note that if_bytes in the data fork might actually be larger than
     * the current data fork size is due to delalloc extents. In that
     * case either the extent count will go down when they are converted
     * to real extents, or the delalloc conversion will take care of the
     * literal area rebalancing.
     */
    if (bytes <= XFS_IFORK_ASIZE(dp))
        return dp->i_d.di_forkoff;

    /*
     * For attr2 we can try to move the forkoff if there is space in the
     * literal area, but for the old format we are done if there is no
     * space in the fixed attribute fork.
     */
    if (!(mp->m_flags & XFS_MOUNT_ATTR2))
        return 0;

    dsize = dp->i_df.if_bytes;

    switch (dp->i_d.di_format) {
    case XFS_DINODE_FMT_EXTENTS:
        /*
         * If there is no attr fork and the data fork is extents, 
         * determine if creating the default attr fork will result
         * in the extents form migrating to btree. If so, the
         * minimum offset only needs to be the space required for
         * the btree root.
         */
        if (!dp->i_d.di_forkoff && dp->i_df.if_bytes >
            xfs_default_attroffset(dp))
            dsize = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
        break;
    case XFS_DINODE_FMT_BTREE:
        /*
         * If we have a data btree then keep forkoff if we have one,
         * otherwise we are adding a new attr, so then we set
         * minforkoff to where the btree root can finish so we have
         * plenty of room for attrs
         */
        if (dp->i_d.di_forkoff) {
            if (offset < dp->i_d.di_forkoff)
                return 0;
            return dp->i_d.di_forkoff;
        }
        dsize = XFS_BMAP_BROOT_SPACE(dp->i_df.if_broot);
        break;
    }

    /*
     * A data fork btree root must have space for at least
     * MINDBTPTRS key/ptr pairs if the data fork is small or empty.
     */
    minforkoff = MAX(dsize, XFS_BMDR_SPACE_CALC(MINDBTPTRS));
    minforkoff = roundup(minforkoff, 8) >> 3;

    /* attr fork btree root can have at least this many key/ptr pairs */
    maxforkoff = XFS_LITINO(mp) - XFS_BMDR_SPACE_CALC(MINABTPTRS);
    maxforkoff = maxforkoff >> 3;   /* rounded down */

    if (offset >= maxforkoff)
        return maxforkoff;
    if (offset >= minforkoff)
        return offset;
    return 0;
}

/*
 * Switch on the ATTR2 superblock bit (implies also FEATURES2)
 */
STATIC void
xfs_sbversion_add_attr2(xfs_mount_t *mp, xfs_trans_t *tp)
{
    if ((mp->m_flags & XFS_MOUNT_ATTR2) &&
        !(xfs_sb_version_hasattr2(&mp->m_sb))) {
        spin_lock(&mp->m_sb_lock);
        if (!xfs_sb_version_hasattr2(&mp->m_sb)) {
            xfs_sb_version_addattr2(&mp->m_sb);
            spin_unlock(&mp->m_sb_lock);
            xfs_mod_sb(tp, XFS_SB_VERSIONNUM | XFS_SB_FEATURES2);
        } else
            spin_unlock(&mp->m_sb_lock);
    }
}

/*
 * Create the initial contents of a shortform attribute list.
 */
void
xfs_attr_shortform_create(xfs_da_args_t *args)
{
    xfs_attr_sf_hdr_t *hdr;
    xfs_inode_t *dp;
    xfs_ifork_t *ifp;

    trace_xfs_attr_sf_create(args);

    dp = args->dp;
    ASSERT(dp != NULL);
    ifp = dp->i_afp;
    ASSERT(ifp != NULL);
    ASSERT(ifp->if_bytes == 0);
    if (dp->i_d.di_aformat == XFS_DINODE_FMT_EXTENTS) {
        ifp->if_flags &= ~XFS_IFEXTENTS;    /* just in case */
        dp->i_d.di_aformat = XFS_DINODE_FMT_LOCAL;
        ifp->if_flags |= XFS_IFINLINE;
    } else {
        ASSERT(ifp->if_flags & XFS_IFINLINE);
    }
    xfs_idata_realloc(dp, sizeof(*hdr), XFS_ATTR_FORK);
    hdr = (xfs_attr_sf_hdr_t *)ifp->if_u1.if_data;
    hdr->count = 0;
    hdr->totsize = cpu_to_be16(sizeof(*hdr));
    xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);
}

/*
 * Add a name/value pair to the shortform attribute list.
 * Overflow from the inode has already been checked for.
 */
void
xfs_attr_shortform_add(xfs_da_args_t *args, int forkoff)
{
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    int i, offset, size;
    xfs_mount_t *mp;
    xfs_inode_t *dp;
    xfs_ifork_t *ifp;

    trace_xfs_attr_sf_add(args);

    dp = args->dp;
    mp = dp->i_mount;
    dp->i_d.di_forkoff = forkoff;

    ifp = dp->i_afp;
    ASSERT(ifp->if_flags & XFS_IFINLINE);
    sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
    sfe = &sf->list[0];
    for (i = 0; i < sf->hdr.count; sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
#ifdef DEBUG
        if (sfe->namelen != args->namelen)
            continue;
        if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
            continue;
        if (!xfs_attr_namesp_match(args->flags, sfe->flags))
            continue;
        ASSERT(0);
#endif
    }

    offset = (char *)sfe - (char *)sf;
    size = XFS_ATTR_SF_ENTSIZE_BYNAME(args->namelen, args->valuelen);
    xfs_idata_realloc(dp, size, XFS_ATTR_FORK);
    sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
    sfe = (xfs_attr_sf_entry_t *)((char *)sf + offset);

    sfe->namelen = args->namelen;
    sfe->valuelen = args->valuelen;
    sfe->flags = XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
    memcpy(sfe->nameval, args->name, args->namelen);
    memcpy(&sfe->nameval[args->namelen], args->value, args->valuelen);
    sf->hdr.count++;
    be16_add_cpu(&sf->hdr.totsize, size);
    xfs_trans_log_inode(args->trans, dp, XFS_ILOG_CORE | XFS_ILOG_ADATA);

    xfs_sbversion_add_attr2(mp, args->trans);
}

/*
 * After the last attribute is removed revert to original inode format,
 * making all literal area available to the data fork once more.
 */
STATIC void
xfs_attr_fork_reset(
    struct xfs_inode    *ip,
    struct xfs_trans    *tp)
{
    xfs_idestroy_fork(ip, XFS_ATTR_FORK);
    ip->i_d.di_forkoff = 0;
    ip->i_d.di_aformat = XFS_DINODE_FMT_EXTENTS;

    ASSERT(ip->i_d.di_anextents == 0);
    ASSERT(ip->i_afp == NULL);

    xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
}

/*
 * Remove an attribute from the shortform attribute list structure.
 */
int
xfs_attr_shortform_remove(xfs_da_args_t *args)
{
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    int base, size=0, end, totsize, i;
    xfs_mount_t *mp;
    xfs_inode_t *dp;

    trace_xfs_attr_sf_remove(args);

    dp = args->dp;
    mp = dp->i_mount;
    base = sizeof(xfs_attr_sf_hdr_t);
    sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
    sfe = &sf->list[0];
    end = sf->hdr.count;
    for (i = 0; i < end; sfe = XFS_ATTR_SF_NEXTENTRY(sfe),
                    base += size, i++) {
        size = XFS_ATTR_SF_ENTSIZE(sfe);
        if (sfe->namelen != args->namelen)
            continue;
        if (memcmp(sfe->nameval, args->name, args->namelen) != 0)
            continue;
        if (!xfs_attr_namesp_match(args->flags, sfe->flags))
            continue;
        break;
    }
    if (i == end)
        return(XFS_ERROR(ENOATTR));

    /*
     * Fix up the attribute fork data, covering the hole
     */
    end = base + size;
    totsize = be16_to_cpu(sf->hdr.totsize);
    if (end != totsize)
        memmove(&((char *)sf)[base], &((char *)sf)[end], totsize - end);
    sf->hdr.count--;
    be16_add_cpu(&sf->hdr.totsize, -size);

    /*
     * Fix up the start offset of the attribute fork
     */
    totsize -= size;
    if (totsize == sizeof(xfs_attr_sf_hdr_t) &&
        (mp->m_flags & XFS_MOUNT_ATTR2) &&
        (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
        !(args->op_flags & XFS_DA_OP_ADDNAME)) {
        xfs_attr_fork_reset(dp, args->trans);
    } else {
        xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
        dp->i_d.di_forkoff = xfs_attr_shortform_bytesfit(dp, totsize);
        ASSERT(dp->i_d.di_forkoff);
        ASSERT(totsize > sizeof(xfs_attr_sf_hdr_t) ||
                (args->op_flags & XFS_DA_OP_ADDNAME) ||
                !(mp->m_flags & XFS_MOUNT_ATTR2) ||
                dp->i_d.di_format == XFS_DINODE_FMT_BTREE);
        xfs_trans_log_inode(args->trans, dp,
                    XFS_ILOG_CORE | XFS_ILOG_ADATA);
    }

    xfs_sbversion_add_attr2(mp, args->trans);

    return(0);
}

/*
 * Look up a name in a shortform attribute list structure.
 */
/*ARGSUSED*/
int
xfs_attr_shortform_lookup(xfs_da_args_t *args)
{
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    int i;
    xfs_ifork_t *ifp;

    trace_xfs_attr_sf_lookup(args);

    ifp = args->dp->i_afp;
    ASSERT(ifp->if_flags & XFS_IFINLINE);
    sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
    sfe = &sf->list[0];
    for (i = 0; i < sf->hdr.count;
                sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
        if (sfe->namelen != args->namelen)
            continue;
        if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
            continue;
        if (!xfs_attr_namesp_match(args->flags, sfe->flags))
            continue;
        return(XFS_ERROR(EEXIST));
    }
    return(XFS_ERROR(ENOATTR));
}

/*
 * Look up a name in a shortform attribute list structure.
 */
/*ARGSUSED*/
int
xfs_attr_shortform_getvalue(xfs_da_args_t *args)
{
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    int i;

    ASSERT(args->dp->i_d.di_aformat == XFS_IFINLINE);
    sf = (xfs_attr_shortform_t *)args->dp->i_afp->if_u1.if_data;
    sfe = &sf->list[0];
    for (i = 0; i < sf->hdr.count;
                sfe = XFS_ATTR_SF_NEXTENTRY(sfe), i++) {
        if (sfe->namelen != args->namelen)
            continue;
        if (memcmp(args->name, sfe->nameval, args->namelen) != 0)
            continue;
        if (!xfs_attr_namesp_match(args->flags, sfe->flags))
            continue;
        if (args->flags & ATTR_KERNOVAL) {
            args->valuelen = sfe->valuelen;
            return(XFS_ERROR(EEXIST));
        }
        if (args->valuelen < sfe->valuelen) {
            args->valuelen = sfe->valuelen;
            return(XFS_ERROR(ERANGE));
        }
        args->valuelen = sfe->valuelen;
        memcpy(args->value, &sfe->nameval[args->namelen],
                            args->valuelen);
        return(XFS_ERROR(EEXIST));
    }
    return(XFS_ERROR(ENOATTR));
}

/*
 * Convert from using the shortform to the leaf.
 */
int
xfs_attr_shortform_to_leaf(xfs_da_args_t *args)
{
    xfs_inode_t *dp;
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    xfs_da_args_t nargs;
    char *tmpbuffer;
    int error, i, size;
    xfs_dablk_t blkno;
    struct xfs_buf *bp;
    xfs_ifork_t *ifp;

    trace_xfs_attr_sf_to_leaf(args);

    dp = args->dp;
    ifp = dp->i_afp;
    sf = (xfs_attr_shortform_t *)ifp->if_u1.if_data;
    size = be16_to_cpu(sf->hdr.totsize);
    tmpbuffer = kmem_alloc(size, KM_SLEEP);
    ASSERT(tmpbuffer != NULL);
    memcpy(tmpbuffer, ifp->if_u1.if_data, size);
    sf = (xfs_attr_shortform_t *)tmpbuffer;

    xfs_idata_realloc(dp, -size, XFS_ATTR_FORK);
    bp = NULL;
    error = xfs_da_grow_inode(args, &blkno);
    if (error) {
        /*
         * If we hit an IO error middle of the transaction inside
         * grow_inode(), we may have inconsistent data. Bail out.
         */
        if (error == EIO)
            goto out;
        xfs_idata_realloc(dp, size, XFS_ATTR_FORK); /* try to put */
        memcpy(ifp->if_u1.if_data, tmpbuffer, size);    /* it back */
        goto out;
    }

    ASSERT(blkno == 0);
    error = xfs_attr_leaf_create(args, blkno, &bp);
    if (error) {
        error = xfs_da_shrink_inode(args, 0, bp);
        bp = NULL;
        if (error)
            goto out;
        xfs_idata_realloc(dp, size, XFS_ATTR_FORK); /* try to put */
        memcpy(ifp->if_u1.if_data, tmpbuffer, size);    /* it back */
        goto out;
    }

    memset((char *)&nargs, 0, sizeof(nargs));
    nargs.dp = dp;
    nargs.firstblock = args->firstblock;
    nargs.flist = args->flist;
    nargs.total = args->total;
    nargs.whichfork = XFS_ATTR_FORK;
    nargs.trans = args->trans;
    nargs.op_flags = XFS_DA_OP_OKNOENT;

    sfe = &sf->list[0];
    for (i = 0; i < sf->hdr.count; i++) {
        nargs.name = sfe->nameval;
        nargs.namelen = sfe->namelen;
        nargs.value = &sfe->nameval[nargs.namelen];
        nargs.valuelen = sfe->valuelen;
        nargs.hashval = xfs_da_hashname(sfe->nameval,
                        sfe->namelen);
        nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(sfe->flags);
        error = xfs_attr_leaf_lookup_int(bp, &nargs); /* set a->index */
        ASSERT(error == ENOATTR);
        error = xfs_attr_leaf_add(bp, &nargs);
        ASSERT(error != ENOSPC);
        if (error)
            goto out;
        sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
    }
    error = 0;

out:
    kmem_free(tmpbuffer);
    return(error);
}

STATIC int
xfs_attr_shortform_compare(const void *a, const void *b)
{
    xfs_attr_sf_sort_t *sa, *sb;

    sa = (xfs_attr_sf_sort_t *)a;
    sb = (xfs_attr_sf_sort_t *)b;
    if (sa->hash < sb->hash) {
        return(-1);
    } else if (sa->hash > sb->hash) {
        return(1);
    } else {
        return(sa->entno - sb->entno);
    }
}


#define XFS_ISRESET_CURSOR(cursor) \
    (!((cursor)->initted) && !((cursor)->hashval) && \
     !((cursor)->blkno) && !((cursor)->offset))
/*
 * Copy out entries of shortform attribute lists for attr_list().
 * Shortform attribute lists are not stored in hashval sorted order.
 * If the output buffer is not large enough to hold them all, then we
 * we have to calculate each entries' hashvalue and sort them before
 * we can begin returning them to the user.
 */
/*ARGSUSED*/
int
xfs_attr_shortform_list(xfs_attr_list_context_t *context)
{
    attrlist_cursor_kern_t *cursor;
    xfs_attr_sf_sort_t *sbuf, *sbp;
    xfs_attr_shortform_t *sf;
    xfs_attr_sf_entry_t *sfe;
    xfs_inode_t *dp;
    int sbsize, nsbuf, count, i;
    int error;

    ASSERT(context != NULL);
    dp = context->dp;
    ASSERT(dp != NULL);
    ASSERT(dp->i_afp != NULL);
    sf = (xfs_attr_shortform_t *)dp->i_afp->if_u1.if_data;
    ASSERT(sf != NULL);
    if (!sf->hdr.count)
        return(0);
    cursor = context->cursor;
    ASSERT(cursor != NULL);

    trace_xfs_attr_list_sf(context);

    /*
     * If the buffer is large enough and the cursor is at the start,
     * do not bother with sorting since we will return everything in
     * one buffer and another call using the cursor won't need to be
     * made.
     * Note the generous fudge factor of 16 overhead bytes per entry.
     * If bufsize is zero then put_listent must be a search function
     * and can just scan through what we have.
     */
    if (context->bufsize == 0 ||
        (XFS_ISRESET_CURSOR(cursor) &&
             (dp->i_afp->if_bytes + sf->hdr.count * 16) < context->bufsize)) {
        for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) {
            error = context->put_listent(context,
                       sfe->flags,
                       sfe->nameval,
                       (int)sfe->namelen,
                       (int)sfe->valuelen,
                       &sfe->nameval[sfe->namelen]);

            /*
             * Either search callback finished early or
             * didn't fit it all in the buffer after all.
             */
            if (context->seen_enough)
                break;

            if (error)
                return error;
            sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
        }
        trace_xfs_attr_list_sf_all(context);
        return(0);
    }

    /* do no more for a search callback */
    if (context->bufsize == 0)
        return 0;

    /*
     * It didn't all fit, so we have to sort everything on hashval.
     */
    sbsize = sf->hdr.count * sizeof(*sbuf);
    sbp = sbuf = kmem_alloc(sbsize, KM_SLEEP | KM_NOFS);

    /*
     * Scan the attribute list for the rest of the entries, storing
     * the relevant info from only those that match into a buffer.
     */
    nsbuf = 0;
    for (i = 0, sfe = &sf->list[0]; i < sf->hdr.count; i++) {
        if (unlikely(
            ((char *)sfe < (char *)sf) ||
            ((char *)sfe >= ((char *)sf + dp->i_afp->if_bytes)))) {
            XFS_CORRUPTION_ERROR("xfs_attr_shortform_list",
                         XFS_ERRLEVEL_LOW,
                         context->dp->i_mount, sfe);
            kmem_free(sbuf);
            return XFS_ERROR(EFSCORRUPTED);
        }

        sbp->entno = i;
        sbp->hash = xfs_da_hashname(sfe->nameval, sfe->namelen);
        sbp->name = sfe->nameval;
        sbp->namelen = sfe->namelen;
        /* These are bytes, and both on-disk, don't endian-flip */
        sbp->valuelen = sfe->valuelen;
        sbp->flags = sfe->flags;
        sfe = XFS_ATTR_SF_NEXTENTRY(sfe);
        sbp++;
        nsbuf++;
    }

    /*
     * Sort the entries on hash then entno.
     */
    xfs_sort(sbuf, nsbuf, sizeof(*sbuf), xfs_attr_shortform_compare);

    /*
     * Re-find our place IN THE SORTED LIST.
     */
    count = 0;
    cursor->initted = 1;
    cursor->blkno = 0;
    for (sbp = sbuf, i = 0; i < nsbuf; i++, sbp++) {
        if (sbp->hash == cursor->hashval) {
            if (cursor->offset == count) {
                break;
            }
            count++;
        } else if (sbp->hash > cursor->hashval) {
            break;
        }
    }
    if (i == nsbuf) {
        kmem_free(sbuf);
        return(0);
    }

    /*
     * Loop putting entries into the user buffer.
     */
    for ( ; i < nsbuf; i++, sbp++) {
        if (cursor->hashval != sbp->hash) {
            cursor->hashval = sbp->hash;
            cursor->offset = 0;
        }
        error = context->put_listent(context,
                    sbp->flags,
                    sbp->name,
                    sbp->namelen,
                    sbp->valuelen,
                    &sbp->name[sbp->namelen]);
        if (error)
            return error;
        if (context->seen_enough)
            break;
        cursor->offset++;
    }

    kmem_free(sbuf);
    return(0);
}

/*
 * Check a leaf attribute block to see if all the entries would fit into
 * a shortform attribute list.
 */
int
xfs_attr_shortform_allfit(
    struct xfs_buf  *bp,
    struct xfs_inode *dp)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_local_t *name_loc;
    int bytes, i;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));

    entry = &leaf->entries[0];
    bytes = sizeof(struct xfs_attr_sf_hdr);
    for (i = 0; i < be16_to_cpu(leaf->hdr.count); entry++, i++) {
        if (entry->flags & XFS_ATTR_INCOMPLETE)
            continue;       /* don't copy partial entries */
        if (!(entry->flags & XFS_ATTR_LOCAL))
            return(0);
        name_loc = xfs_attr_leaf_name_local(leaf, i);
        if (name_loc->namelen >= XFS_ATTR_SF_ENTSIZE_MAX)
            return(0);
        if (be16_to_cpu(name_loc->valuelen) >= XFS_ATTR_SF_ENTSIZE_MAX)
            return(0);
        bytes += sizeof(struct xfs_attr_sf_entry)-1
                + name_loc->namelen
                + be16_to_cpu(name_loc->valuelen);
    }
    if ((dp->i_mount->m_flags & XFS_MOUNT_ATTR2) &&
        (dp->i_d.di_format != XFS_DINODE_FMT_BTREE) &&
        (bytes == sizeof(struct xfs_attr_sf_hdr)))
        return(-1);
    return(xfs_attr_shortform_bytesfit(dp, bytes));
}

/*
 * Convert a leaf attribute list to shortform attribute list
 */
int
xfs_attr_leaf_to_shortform(
    struct xfs_buf  *bp,
    xfs_da_args_t   *args,
    int     forkoff)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_local_t *name_loc;
    xfs_da_args_t nargs;
    xfs_inode_t *dp;
    char *tmpbuffer;
    int error, i;

    trace_xfs_attr_leaf_to_sf(args);

    dp = args->dp;
    tmpbuffer = kmem_alloc(XFS_LBSIZE(dp->i_mount), KM_SLEEP);
    ASSERT(tmpbuffer != NULL);

    ASSERT(bp != NULL);
    memcpy(tmpbuffer, bp->b_addr, XFS_LBSIZE(dp->i_mount));
    leaf = (xfs_attr_leafblock_t *)tmpbuffer;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    memset(bp->b_addr, 0, XFS_LBSIZE(dp->i_mount));

    /*
     * Clean out the prior contents of the attribute list.
     */
    error = xfs_da_shrink_inode(args, 0, bp);
    if (error)
        goto out;

    if (forkoff == -1) {
        ASSERT(dp->i_mount->m_flags & XFS_MOUNT_ATTR2);
        ASSERT(dp->i_d.di_format != XFS_DINODE_FMT_BTREE);
        xfs_attr_fork_reset(dp, args->trans);
        goto out;
    }

    xfs_attr_shortform_create(args);

    /*
     * Copy the attributes
     */
    memset((char *)&nargs, 0, sizeof(nargs));
    nargs.dp = dp;
    nargs.firstblock = args->firstblock;
    nargs.flist = args->flist;
    nargs.total = args->total;
    nargs.whichfork = XFS_ATTR_FORK;
    nargs.trans = args->trans;
    nargs.op_flags = XFS_DA_OP_OKNOENT;
    entry = &leaf->entries[0];
    for (i = 0; i < be16_to_cpu(leaf->hdr.count); entry++, i++) {
        if (entry->flags & XFS_ATTR_INCOMPLETE)
            continue;   /* don't copy partial entries */
        if (!entry->nameidx)
            continue;
        ASSERT(entry->flags & XFS_ATTR_LOCAL);
        name_loc = xfs_attr_leaf_name_local(leaf, i);
        nargs.name = name_loc->nameval;
        nargs.namelen = name_loc->namelen;
        nargs.value = &name_loc->nameval[nargs.namelen];
        nargs.valuelen = be16_to_cpu(name_loc->valuelen);
        nargs.hashval = be32_to_cpu(entry->hashval);
        nargs.flags = XFS_ATTR_NSP_ONDISK_TO_ARGS(entry->flags);
        xfs_attr_shortform_add(&nargs, forkoff);
    }
    error = 0;

out:
    kmem_free(tmpbuffer);
    return(error);
}

/*
 * Convert from using a single leaf to a root node and a leaf.
 */
int
xfs_attr_leaf_to_node(xfs_da_args_t *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_da_intnode_t *node;
    xfs_inode_t *dp;
    struct xfs_buf *bp1, *bp2;
    xfs_dablk_t blkno;
    int error;

    trace_xfs_attr_leaf_to_node(args);

    dp = args->dp;
    bp1 = bp2 = NULL;
    error = xfs_da_grow_inode(args, &blkno);
    if (error)
        goto out;
    error = xfs_da_read_buf(args->trans, args->dp, 0, -1, &bp1,
                         XFS_ATTR_FORK);
    if (error)
        goto out;
    ASSERT(bp1 != NULL);
    bp2 = NULL;
    error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp2,
                        XFS_ATTR_FORK);
    if (error)
        goto out;
    ASSERT(bp2 != NULL);
    memcpy(bp2->b_addr, bp1->b_addr, XFS_LBSIZE(dp->i_mount));
    bp1 = NULL;
    xfs_trans_log_buf(args->trans, bp2, 0, XFS_LBSIZE(dp->i_mount) - 1);

    /*
     * Set up the new root node.
     */
    error = xfs_da_node_create(args, 0, 1, &bp1, XFS_ATTR_FORK);
    if (error)
        goto out;
    node = bp1->b_addr;
    leaf = bp2->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    /* both on-disk, don't endian-flip twice */
    node->btree[0].hashval =
        leaf->entries[be16_to_cpu(leaf->hdr.count)-1 ].hashval;
    node->btree[0].before = cpu_to_be32(blkno);
    node->hdr.count = cpu_to_be16(1);
    xfs_trans_log_buf(args->trans, bp1, 0, XFS_LBSIZE(dp->i_mount) - 1);
    error = 0;
out:
    return(error);
}


/*========================================================================
 * Routines used for growing the Btree.
 *========================================================================*/

/*
 * Create the initial contents of a leaf attribute list
 * or a leaf in a node attribute list.
 */
STATIC int
xfs_attr_leaf_create(
    xfs_da_args_t   *args,
    xfs_dablk_t blkno,
    struct xfs_buf  **bpp)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_hdr_t *hdr;
    xfs_inode_t *dp;
    struct xfs_buf *bp;
    int error;

    trace_xfs_attr_leaf_create(args);

    dp = args->dp;
    ASSERT(dp != NULL);
    error = xfs_da_get_buf(args->trans, args->dp, blkno, -1, &bp,
                        XFS_ATTR_FORK);
    if (error)
        return(error);
    ASSERT(bp != NULL);
    leaf = bp->b_addr;
    memset((char *)leaf, 0, XFS_LBSIZE(dp->i_mount));
    hdr = &leaf->hdr;
    hdr->info.magic = cpu_to_be16(XFS_ATTR_LEAF_MAGIC);
    hdr->firstused = cpu_to_be16(XFS_LBSIZE(dp->i_mount));
    if (!hdr->firstused) {
        hdr->firstused = cpu_to_be16(
            XFS_LBSIZE(dp->i_mount) - XFS_ATTR_LEAF_NAME_ALIGN);
    }

    hdr->freemap[0].base = cpu_to_be16(sizeof(xfs_attr_leaf_hdr_t));
    hdr->freemap[0].size = cpu_to_be16(be16_to_cpu(hdr->firstused) -
                       sizeof(xfs_attr_leaf_hdr_t));

    xfs_trans_log_buf(args->trans, bp, 0, XFS_LBSIZE(dp->i_mount) - 1);

    *bpp = bp;
    return(0);
}

/*
 * Split the leaf node, rebalance, then add the new entry.
 */
int
xfs_attr_leaf_split(xfs_da_state_t *state, xfs_da_state_blk_t *oldblk,
                   xfs_da_state_blk_t *newblk)
{
    xfs_dablk_t blkno;
    int error;

    trace_xfs_attr_leaf_split(state->args);

    /*
     * Allocate space for a new leaf node.
     */
    ASSERT(oldblk->magic == XFS_ATTR_LEAF_MAGIC);
    error = xfs_da_grow_inode(state->args, &blkno);
    if (error)
        return(error);
    error = xfs_attr_leaf_create(state->args, blkno, &newblk->bp);
    if (error)
        return(error);
    newblk->blkno = blkno;
    newblk->magic = XFS_ATTR_LEAF_MAGIC;

    /*
     * Rebalance the entries across the two leaves.
     * NOTE: rebalance() currently depends on the 2nd block being empty.
     */
    xfs_attr_leaf_rebalance(state, oldblk, newblk);
    error = xfs_da_blk_link(state, oldblk, newblk);
    if (error)
        return(error);

    /*
     * Save info on "old" attribute for "atomic rename" ops, leaf_add()
     * modifies the index/blkno/rmtblk/rmtblkcnt fields to show the
     * "new" attrs info.  Will need the "old" info to remove it later.
     *
     * Insert the "new" entry in the correct block.
     */
    if (state->inleaf) {
        trace_xfs_attr_leaf_add_old(state->args);
        error = xfs_attr_leaf_add(oldblk->bp, state->args);
    } else {
        trace_xfs_attr_leaf_add_new(state->args);
        error = xfs_attr_leaf_add(newblk->bp, state->args);
    }

    /*
     * Update last hashval in each block since we added the name.
     */
    oldblk->hashval = xfs_attr_leaf_lasthash(oldblk->bp, NULL);
    newblk->hashval = xfs_attr_leaf_lasthash(newblk->bp, NULL);
    return(error);
}

/*
 * Add a name to the leaf attribute list structure.
 */
int
xfs_attr_leaf_add(
    struct xfs_buf      *bp,
    struct xfs_da_args  *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_hdr_t *hdr;
    xfs_attr_leaf_map_t *map;
    int tablesize, entsize, sum, tmp, i;

    trace_xfs_attr_leaf_add(args);

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT((args->index >= 0)
        && (args->index <= be16_to_cpu(leaf->hdr.count)));
    hdr = &leaf->hdr;
    entsize = xfs_attr_leaf_newentsize(args->namelen, args->valuelen,
               args->trans->t_mountp->m_sb.sb_blocksize, NULL);

    /*
     * Search through freemap for first-fit on new name length.
     * (may need to figure in size of entry struct too)
     */
    tablesize = (be16_to_cpu(hdr->count) + 1)
                    * sizeof(xfs_attr_leaf_entry_t)
                    + sizeof(xfs_attr_leaf_hdr_t);
    map = &hdr->freemap[XFS_ATTR_LEAF_MAPSIZE-1];
    for (sum = 0, i = XFS_ATTR_LEAF_MAPSIZE-1; i >= 0; map--, i--) {
        if (tablesize > be16_to_cpu(hdr->firstused)) {
            sum += be16_to_cpu(map->size);
            continue;
        }
        if (!map->size)
            continue;   /* no space in this map */
        tmp = entsize;
        if (be16_to_cpu(map->base) < be16_to_cpu(hdr->firstused))
            tmp += sizeof(xfs_attr_leaf_entry_t);
        if (be16_to_cpu(map->size) >= tmp) {
            tmp = xfs_attr_leaf_add_work(bp, args, i);
            return(tmp);
        }
        sum += be16_to_cpu(map->size);
    }

    /*
     * If there are no holes in the address space of the block,
     * and we don't have enough freespace, then compaction will do us
     * no good and we should just give up.
     */
    if (!hdr->holes && (sum < entsize))
        return(XFS_ERROR(ENOSPC));

    /*
     * Compact the entries to coalesce free space.
     * This may change the hdr->count via dropping INCOMPLETE entries.
     */
    xfs_attr_leaf_compact(args->trans, bp);

    /*
     * After compaction, the block is guaranteed to have only one
     * free region, in freemap[0].  If it is not big enough, give up.
     */
    if (be16_to_cpu(hdr->freemap[0].size)
                < (entsize + sizeof(xfs_attr_leaf_entry_t)))
        return(XFS_ERROR(ENOSPC));

    return(xfs_attr_leaf_add_work(bp, args, 0));
}

/*
 * Add a name to a leaf attribute list structure.
 */
STATIC int
xfs_attr_leaf_add_work(
    struct xfs_buf  *bp,
    xfs_da_args_t   *args,
    int     mapindex)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_hdr_t *hdr;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_local_t *name_loc;
    xfs_attr_leaf_name_remote_t *name_rmt;
    xfs_attr_leaf_map_t *map;
    xfs_mount_t *mp;
    int tmp, i;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    hdr = &leaf->hdr;
    ASSERT((mapindex >= 0) && (mapindex < XFS_ATTR_LEAF_MAPSIZE));
    ASSERT((args->index >= 0) && (args->index <= be16_to_cpu(hdr->count)));

    /*
     * Force open some space in the entry array and fill it in.
     */
    entry = &leaf->entries[args->index];
    if (args->index < be16_to_cpu(hdr->count)) {
        tmp  = be16_to_cpu(hdr->count) - args->index;
        tmp *= sizeof(xfs_attr_leaf_entry_t);
        memmove((char *)(entry+1), (char *)entry, tmp);
        xfs_trans_log_buf(args->trans, bp,
            XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
    }
    be16_add_cpu(&hdr->count, 1);

    /*
     * Allocate space for the new string (at the end of the run).
     */
    map = &hdr->freemap[mapindex];
    mp = args->trans->t_mountp;
    ASSERT(be16_to_cpu(map->base) < XFS_LBSIZE(mp));
    ASSERT((be16_to_cpu(map->base) & 0x3) == 0);
    ASSERT(be16_to_cpu(map->size) >=
        xfs_attr_leaf_newentsize(args->namelen, args->valuelen,
                     mp->m_sb.sb_blocksize, NULL));
    ASSERT(be16_to_cpu(map->size) < XFS_LBSIZE(mp));
    ASSERT((be16_to_cpu(map->size) & 0x3) == 0);
    be16_add_cpu(&map->size,
        -xfs_attr_leaf_newentsize(args->namelen, args->valuelen,
                      mp->m_sb.sb_blocksize, &tmp));
    entry->nameidx = cpu_to_be16(be16_to_cpu(map->base) +
                     be16_to_cpu(map->size));
    entry->hashval = cpu_to_be32(args->hashval);
    entry->flags = tmp ? XFS_ATTR_LOCAL : 0;
    entry->flags |= XFS_ATTR_NSP_ARGS_TO_ONDISK(args->flags);
    if (args->op_flags & XFS_DA_OP_RENAME) {
        entry->flags |= XFS_ATTR_INCOMPLETE;
        if ((args->blkno2 == args->blkno) &&
            (args->index2 <= args->index)) {
            args->index2++;
        }
    }
    xfs_trans_log_buf(args->trans, bp,
              XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
    ASSERT((args->index == 0) ||
           (be32_to_cpu(entry->hashval) >= be32_to_cpu((entry-1)->hashval)));
    ASSERT((args->index == be16_to_cpu(hdr->count)-1) ||
           (be32_to_cpu(entry->hashval) <= be32_to_cpu((entry+1)->hashval)));

    /*
     * For "remote" attribute values, simply note that we need to
     * allocate space for the "remote" value.  We can't actually
     * allocate the extents in this transaction, and we can't decide
     * which blocks they should be as we might allocate more blocks
     * as part of this transaction (a split operation for example).
     */
    if (entry->flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf, args->index);
        name_loc->namelen = args->namelen;
        name_loc->valuelen = cpu_to_be16(args->valuelen);
        memcpy((char *)name_loc->nameval, args->name, args->namelen);
        memcpy((char *)&name_loc->nameval[args->namelen], args->value,
                   be16_to_cpu(name_loc->valuelen));
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf, args->index);
        name_rmt->namelen = args->namelen;
        memcpy((char *)name_rmt->name, args->name, args->namelen);
        entry->flags |= XFS_ATTR_INCOMPLETE;
        /* just in case */
        name_rmt->valuelen = 0;
        name_rmt->valueblk = 0;
        args->rmtblkno = 1;
        args->rmtblkcnt = XFS_B_TO_FSB(mp, args->valuelen);
    }
    xfs_trans_log_buf(args->trans, bp,
         XFS_DA_LOGRANGE(leaf, xfs_attr_leaf_name(leaf, args->index),
                   xfs_attr_leaf_entsize(leaf, args->index)));

    /*
     * Update the control info for this leaf node
     */
    if (be16_to_cpu(entry->nameidx) < be16_to_cpu(hdr->firstused)) {
        /* both on-disk, don't endian-flip twice */
        hdr->firstused = entry->nameidx;
    }
    ASSERT(be16_to_cpu(hdr->firstused) >=
           ((be16_to_cpu(hdr->count) * sizeof(*entry)) + sizeof(*hdr)));
    tmp = (be16_to_cpu(hdr->count)-1) * sizeof(xfs_attr_leaf_entry_t)
                    + sizeof(xfs_attr_leaf_hdr_t);
    map = &hdr->freemap[0];
    for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; map++, i++) {
        if (be16_to_cpu(map->base) == tmp) {
            be16_add_cpu(&map->base, sizeof(xfs_attr_leaf_entry_t));
            be16_add_cpu(&map->size,
                 -((int)sizeof(xfs_attr_leaf_entry_t)));
        }
    }
    be16_add_cpu(&hdr->usedbytes, xfs_attr_leaf_entsize(leaf, args->index));
    xfs_trans_log_buf(args->trans, bp,
        XFS_DA_LOGRANGE(leaf, hdr, sizeof(*hdr)));
    return(0);
}

/*
 * Garbage collect a leaf attribute list block by copying it to a new buffer.
 */
STATIC void
xfs_attr_leaf_compact(
    struct xfs_trans *trans,
    struct xfs_buf  *bp)
{
    xfs_attr_leafblock_t *leaf_s, *leaf_d;
    xfs_attr_leaf_hdr_t *hdr_s, *hdr_d;
    xfs_mount_t *mp;
    char *tmpbuffer;

    mp = trans->t_mountp;
    tmpbuffer = kmem_alloc(XFS_LBSIZE(mp), KM_SLEEP);
    ASSERT(tmpbuffer != NULL);
    memcpy(tmpbuffer, bp->b_addr, XFS_LBSIZE(mp));
    memset(bp->b_addr, 0, XFS_LBSIZE(mp));

    /*
     * Copy basic information
     */
    leaf_s = (xfs_attr_leafblock_t *)tmpbuffer;
    leaf_d = bp->b_addr;
    hdr_s = &leaf_s->hdr;
    hdr_d = &leaf_d->hdr;
    hdr_d->info = hdr_s->info;  /* struct copy */
    hdr_d->firstused = cpu_to_be16(XFS_LBSIZE(mp));
    /* handle truncation gracefully */
    if (!hdr_d->firstused) {
        hdr_d->firstused = cpu_to_be16(
                XFS_LBSIZE(mp) - XFS_ATTR_LEAF_NAME_ALIGN);
    }
    hdr_d->usedbytes = 0;
    hdr_d->count = 0;
    hdr_d->holes = 0;
    hdr_d->freemap[0].base = cpu_to_be16(sizeof(xfs_attr_leaf_hdr_t));
    hdr_d->freemap[0].size = cpu_to_be16(be16_to_cpu(hdr_d->firstused) -
                         sizeof(xfs_attr_leaf_hdr_t));

    /*
     * Copy all entry's in the same (sorted) order,
     * but allocate name/value pairs packed and in sequence.
     */
    xfs_attr_leaf_moveents(leaf_s, 0, leaf_d, 0,
                be16_to_cpu(hdr_s->count), mp);
    xfs_trans_log_buf(trans, bp, 0, XFS_LBSIZE(mp) - 1);

    kmem_free(tmpbuffer);
}

/*
 * Redistribute the attribute list entries between two leaf nodes,
 * taking into account the size of the new entry.
 *
 * NOTE: if new block is empty, then it will get the upper half of the
 * old block.  At present, all (one) callers pass in an empty second block.
 *
 * This code adjusts the args->index/blkno and args->index2/blkno2 fields
 * to match what it is doing in splitting the attribute leaf block.  Those
 * values are used in "atomic rename" operations on attributes.  Note that
 * the "new" and "old" values can end up in different blocks.
 */
STATIC void
xfs_attr_leaf_rebalance(xfs_da_state_t *state, xfs_da_state_blk_t *blk1,
                       xfs_da_state_blk_t *blk2)
{
    xfs_da_args_t *args;
    xfs_da_state_blk_t *tmp_blk;
    xfs_attr_leafblock_t *leaf1, *leaf2;
    xfs_attr_leaf_hdr_t *hdr1, *hdr2;
    int count, totallen, max, space, swap;

    /*
     * Set up environment.
     */
    ASSERT(blk1->magic == XFS_ATTR_LEAF_MAGIC);
    ASSERT(blk2->magic == XFS_ATTR_LEAF_MAGIC);
    leaf1 = blk1->bp->b_addr;
    leaf2 = blk2->bp->b_addr;
    ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(leaf2->hdr.count == 0);
    args = state->args;

    trace_xfs_attr_leaf_rebalance(args);

    /*
     * Check ordering of blocks, reverse if it makes things simpler.
     *
     * NOTE: Given that all (current) callers pass in an empty
     * second block, this code should never set "swap".
     */
    swap = 0;
    if (xfs_attr_leaf_order(blk1->bp, blk2->bp)) {
        tmp_blk = blk1;
        blk1 = blk2;
        blk2 = tmp_blk;
        leaf1 = blk1->bp->b_addr;
        leaf2 = blk2->bp->b_addr;
        swap = 1;
    }
    hdr1 = &leaf1->hdr;
    hdr2 = &leaf2->hdr;

    /*
     * Examine entries until we reduce the absolute difference in
     * byte usage between the two blocks to a minimum.  Then get
     * the direction to copy and the number of elements to move.
     *
     * "inleaf" is true if the new entry should be inserted into blk1.
     * If "swap" is also true, then reverse the sense of "inleaf".
     */
    state->inleaf = xfs_attr_leaf_figure_balance(state, blk1, blk2,
                                &count, &totallen);
    if (swap)
        state->inleaf = !state->inleaf;

    /*
     * Move any entries required from leaf to leaf:
     */
    if (count < be16_to_cpu(hdr1->count)) {
        /*
         * Figure the total bytes to be added to the destination leaf.
         */
        /* number entries being moved */
        count = be16_to_cpu(hdr1->count) - count;
        space  = be16_to_cpu(hdr1->usedbytes) - totallen;
        space += count * sizeof(xfs_attr_leaf_entry_t);

        /*
         * leaf2 is the destination, compact it if it looks tight.
         */
        max  = be16_to_cpu(hdr2->firstused)
                        - sizeof(xfs_attr_leaf_hdr_t);
        max -= be16_to_cpu(hdr2->count) * sizeof(xfs_attr_leaf_entry_t);
        if (space > max) {
            xfs_attr_leaf_compact(args->trans, blk2->bp);
        }

        /*
         * Move high entries from leaf1 to low end of leaf2.
         */
        xfs_attr_leaf_moveents(leaf1, be16_to_cpu(hdr1->count) - count,
                leaf2, 0, count, state->mp);

        xfs_trans_log_buf(args->trans, blk1->bp, 0, state->blocksize-1);
        xfs_trans_log_buf(args->trans, blk2->bp, 0, state->blocksize-1);
    } else if (count > be16_to_cpu(hdr1->count)) {
        /*
         * I assert that since all callers pass in an empty
         * second buffer, this code should never execute.
         */
        ASSERT(0);

        /*
         * Figure the total bytes to be added to the destination leaf.
         */
        /* number entries being moved */
        count -= be16_to_cpu(hdr1->count);
        space  = totallen - be16_to_cpu(hdr1->usedbytes);
        space += count * sizeof(xfs_attr_leaf_entry_t);

        /*
         * leaf1 is the destination, compact it if it looks tight.
         */
        max  = be16_to_cpu(hdr1->firstused)
                        - sizeof(xfs_attr_leaf_hdr_t);
        max -= be16_to_cpu(hdr1->count) * sizeof(xfs_attr_leaf_entry_t);
        if (space > max) {
            xfs_attr_leaf_compact(args->trans, blk1->bp);
        }

        /*
         * Move low entries from leaf2 to high end of leaf1.
         */
        xfs_attr_leaf_moveents(leaf2, 0, leaf1,
                be16_to_cpu(hdr1->count), count, state->mp);

        xfs_trans_log_buf(args->trans, blk1->bp, 0, state->blocksize-1);
        xfs_trans_log_buf(args->trans, blk2->bp, 0, state->blocksize-1);
    }

    /*
     * Copy out last hashval in each block for B-tree code.
     */
    blk1->hashval = be32_to_cpu(
        leaf1->entries[be16_to_cpu(leaf1->hdr.count)-1].hashval);
    blk2->hashval = be32_to_cpu(
        leaf2->entries[be16_to_cpu(leaf2->hdr.count)-1].hashval);

    /*
     * Adjust the expected index for insertion.
     * NOTE: this code depends on the (current) situation that the
     * second block was originally empty.
     *
     * If the insertion point moved to the 2nd block, we must adjust
     * the index.  We must also track the entry just following the
     * new entry for use in an "atomic rename" operation, that entry
     * is always the "old" entry and the "new" entry is what we are
     * inserting.  The index/blkno fields refer to the "old" entry,
     * while the index2/blkno2 fields refer to the "new" entry.
     */
    if (blk1->index > be16_to_cpu(leaf1->hdr.count)) {
        ASSERT(state->inleaf == 0);
        blk2->index = blk1->index - be16_to_cpu(leaf1->hdr.count);
        args->index = args->index2 = blk2->index;
        args->blkno = args->blkno2 = blk2->blkno;
    } else if (blk1->index == be16_to_cpu(leaf1->hdr.count)) {
        if (state->inleaf) {
            args->index = blk1->index;
            args->blkno = blk1->blkno;
            args->index2 = 0;
            args->blkno2 = blk2->blkno;
        } else {
            /*
             * On a double leaf split, the original attr location
             * is already stored in blkno2/index2, so don't
             * overwrite it overwise we corrupt the tree.
             */
            blk2->index = blk1->index
                    - be16_to_cpu(leaf1->hdr.count);
            args->index = blk2->index;
            args->blkno = blk2->blkno;
            if (!state->extravalid) {
                /*
                 * set the new attr location to match the old
                 * one and let the higher level split code
                 * decide where in the leaf to place it.
                 */
                args->index2 = blk2->index;
                args->blkno2 = blk2->blkno;
            }
        }
    } else {
        ASSERT(state->inleaf == 1);
        args->index = args->index2 = blk1->index;
        args->blkno = args->blkno2 = blk1->blkno;
    }
}

/*
 * Examine entries until we reduce the absolute difference in
 * byte usage between the two blocks to a minimum.
 * GROT: Is this really necessary?  With other than a 512 byte blocksize,
 * GROT: there will always be enough room in either block for a new entry.
 * GROT: Do a double-split for this case?
 */
STATIC int
xfs_attr_leaf_figure_balance(xfs_da_state_t *state,
                    xfs_da_state_blk_t *blk1,
                    xfs_da_state_blk_t *blk2,
                    int *countarg, int *usedbytesarg)
{
    xfs_attr_leafblock_t *leaf1, *leaf2;
    xfs_attr_leaf_hdr_t *hdr1, *hdr2;
    xfs_attr_leaf_entry_t *entry;
    int count, max, index, totallen, half;
    int lastdelta, foundit, tmp;

    /*
     * Set up environment.
     */
    leaf1 = blk1->bp->b_addr;
    leaf2 = blk2->bp->b_addr;
    hdr1 = &leaf1->hdr;
    hdr2 = &leaf2->hdr;
    foundit = 0;
    totallen = 0;

    /*
     * Examine entries until we reduce the absolute difference in
     * byte usage between the two blocks to a minimum.
     */
    max = be16_to_cpu(hdr1->count) + be16_to_cpu(hdr2->count);
    half  = (max+1) * sizeof(*entry);
    half += be16_to_cpu(hdr1->usedbytes) +
        be16_to_cpu(hdr2->usedbytes) +
        xfs_attr_leaf_newentsize(
                state->args->namelen,
                state->args->valuelen,
                state->blocksize, NULL);
    half /= 2;
    lastdelta = state->blocksize;
    entry = &leaf1->entries[0];
    for (count = index = 0; count < max; entry++, index++, count++) {

#define XFS_ATTR_ABS(A) (((A) < 0) ? -(A) : (A))
        /*
         * The new entry is in the first block, account for it.
         */
        if (count == blk1->index) {
            tmp = totallen + sizeof(*entry) +
                xfs_attr_leaf_newentsize(
                        state->args->namelen,
                        state->args->valuelen,
                        state->blocksize, NULL);
            if (XFS_ATTR_ABS(half - tmp) > lastdelta)
                break;
            lastdelta = XFS_ATTR_ABS(half - tmp);
            totallen = tmp;
            foundit = 1;
        }

        /*
         * Wrap around into the second block if necessary.
         */
        if (count == be16_to_cpu(hdr1->count)) {
            leaf1 = leaf2;
            entry = &leaf1->entries[0];
            index = 0;
        }

        /*
         * Figure out if next leaf entry would be too much.
         */
        tmp = totallen + sizeof(*entry) + xfs_attr_leaf_entsize(leaf1,
                                    index);
        if (XFS_ATTR_ABS(half - tmp) > lastdelta)
            break;
        lastdelta = XFS_ATTR_ABS(half - tmp);
        totallen = tmp;
#undef XFS_ATTR_ABS
    }

    /*
     * Calculate the number of usedbytes that will end up in lower block.
     * If new entry not in lower block, fix up the count.
     */
    totallen -= count * sizeof(*entry);
    if (foundit) {
        totallen -= sizeof(*entry) +
                xfs_attr_leaf_newentsize(
                        state->args->namelen,
                        state->args->valuelen,
                        state->blocksize, NULL);
    }

    *countarg = count;
    *usedbytesarg = totallen;
    return(foundit);
}

/*========================================================================
 * Routines used for shrinking the Btree.
 *========================================================================*/

/*
 * Check a leaf block and its neighbors to see if the block should be
 * collapsed into one or the other neighbor.  Always keep the block
 * with the smaller block number.
 * If the current block is over 50% full, don't try to join it, return 0.
 * If the block is empty, fill in the state structure and return 2.
 * If it can be collapsed, fill in the state structure and return 1.
 * If nothing can be done, return 0.
 *
 * GROT: allow for INCOMPLETE entries in calculation.
 */
int
xfs_attr_leaf_toosmall(xfs_da_state_t *state, int *action)
{
    xfs_attr_leafblock_t *leaf;
    xfs_da_state_blk_t *blk;
    xfs_da_blkinfo_t *info;
    int count, bytes, forward, error, retval, i;
    xfs_dablk_t blkno;
    struct xfs_buf *bp;

    /*
     * Check for the degenerate case of the block being over 50% full.
     * If so, it's not worth even looking to see if we might be able
     * to coalesce with a sibling.
     */
    blk = &state->path.blk[ state->path.active-1 ];
    info = blk->bp->b_addr;
    ASSERT(info->magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    leaf = (xfs_attr_leafblock_t *)info;
    count = be16_to_cpu(leaf->hdr.count);
    bytes = sizeof(xfs_attr_leaf_hdr_t) +
        count * sizeof(xfs_attr_leaf_entry_t) +
        be16_to_cpu(leaf->hdr.usedbytes);
    if (bytes > (state->blocksize >> 1)) {
        *action = 0;    /* blk over 50%, don't try to join */
        return(0);
    }

    /*
     * Check for the degenerate case of the block being empty.
     * If the block is empty, we'll simply delete it, no need to
     * coalesce it with a sibling block.  We choose (arbitrarily)
     * to merge with the forward block unless it is NULL.
     */
    if (count == 0) {
        /*
         * Make altpath point to the block we want to keep and
         * path point to the block we want to drop (this one).
         */
        forward = (info->forw != 0);
        memcpy(&state->altpath, &state->path, sizeof(state->path));
        error = xfs_da_path_shift(state, &state->altpath, forward,
                         0, &retval);
        if (error)
            return(error);
        if (retval) {
            *action = 0;
        } else {
            *action = 2;
        }
        return(0);
    }

    /*
     * Examine each sibling block to see if we can coalesce with
     * at least 25% free space to spare.  We need to figure out
     * whether to merge with the forward or the backward block.
     * We prefer coalescing with the lower numbered sibling so as
     * to shrink an attribute list over time.
     */
    /* start with smaller blk num */
    forward = (be32_to_cpu(info->forw) < be32_to_cpu(info->back));
    for (i = 0; i < 2; forward = !forward, i++) {
        if (forward)
            blkno = be32_to_cpu(info->forw);
        else
            blkno = be32_to_cpu(info->back);
        if (blkno == 0)
            continue;
        error = xfs_da_read_buf(state->args->trans, state->args->dp,
                    blkno, -1, &bp, XFS_ATTR_FORK);
        if (error)
            return(error);
        ASSERT(bp != NULL);

        leaf = (xfs_attr_leafblock_t *)info;
        count  = be16_to_cpu(leaf->hdr.count);
        bytes  = state->blocksize - (state->blocksize>>2);
        bytes -= be16_to_cpu(leaf->hdr.usedbytes);
        leaf = bp->b_addr;
        ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
        count += be16_to_cpu(leaf->hdr.count);
        bytes -= be16_to_cpu(leaf->hdr.usedbytes);
        bytes -= count * sizeof(xfs_attr_leaf_entry_t);
        bytes -= sizeof(xfs_attr_leaf_hdr_t);
        xfs_trans_brelse(state->args->trans, bp);
        if (bytes >= 0)
            break;  /* fits with at least 25% to spare */
    }
    if (i >= 2) {
        *action = 0;
        return(0);
    }

    /*
     * Make altpath point to the block we want to keep (the lower
     * numbered block) and path point to the block we want to drop.
     */
    memcpy(&state->altpath, &state->path, sizeof(state->path));
    if (blkno < blk->blkno) {
        error = xfs_da_path_shift(state, &state->altpath, forward,
                         0, &retval);
    } else {
        error = xfs_da_path_shift(state, &state->path, forward,
                         0, &retval);
    }
    if (error)
        return(error);
    if (retval) {
        *action = 0;
    } else {
        *action = 1;
    }
    return(0);
}

/*
 * Remove a name from the leaf attribute list structure.
 *
 * Return 1 if leaf is less than 37% full, 0 if >= 37% full.
 * If two leaves are 37% full, when combined they will leave 25% free.
 */
int
xfs_attr_leaf_remove(
    struct xfs_buf  *bp,
    xfs_da_args_t   *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_hdr_t *hdr;
    xfs_attr_leaf_map_t *map;
    xfs_attr_leaf_entry_t *entry;
    int before, after, smallest, entsize;
    int tablesize, tmp, i;
    xfs_mount_t *mp;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    hdr = &leaf->hdr;
    mp = args->trans->t_mountp;
    ASSERT((be16_to_cpu(hdr->count) > 0)
        && (be16_to_cpu(hdr->count) < (XFS_LBSIZE(mp)/8)));
    ASSERT((args->index >= 0)
        && (args->index < be16_to_cpu(hdr->count)));
    ASSERT(be16_to_cpu(hdr->firstused) >=
           ((be16_to_cpu(hdr->count) * sizeof(*entry)) + sizeof(*hdr)));
    entry = &leaf->entries[args->index];
    ASSERT(be16_to_cpu(entry->nameidx) >= be16_to_cpu(hdr->firstused));
    ASSERT(be16_to_cpu(entry->nameidx) < XFS_LBSIZE(mp));

    /*
     * Scan through free region table:
     *    check for adjacency of free'd entry with an existing one,
     *    find smallest free region in case we need to replace it,
     *    adjust any map that borders the entry table,
     */
    tablesize = be16_to_cpu(hdr->count) * sizeof(xfs_attr_leaf_entry_t)
                    + sizeof(xfs_attr_leaf_hdr_t);
    map = &hdr->freemap[0];
    tmp = be16_to_cpu(map->size);
    before = after = -1;
    smallest = XFS_ATTR_LEAF_MAPSIZE - 1;
    entsize = xfs_attr_leaf_entsize(leaf, args->index);
    for (i = 0; i < XFS_ATTR_LEAF_MAPSIZE; map++, i++) {
        ASSERT(be16_to_cpu(map->base) < XFS_LBSIZE(mp));
        ASSERT(be16_to_cpu(map->size) < XFS_LBSIZE(mp));
        if (be16_to_cpu(map->base) == tablesize) {
            be16_add_cpu(&map->base,
                 -((int)sizeof(xfs_attr_leaf_entry_t)));
            be16_add_cpu(&map->size, sizeof(xfs_attr_leaf_entry_t));
        }

        if ((be16_to_cpu(map->base) + be16_to_cpu(map->size))
                == be16_to_cpu(entry->nameidx)) {
            before = i;
        } else if (be16_to_cpu(map->base)
            == (be16_to_cpu(entry->nameidx) + entsize)) {
            after = i;
        } else if (be16_to_cpu(map->size) < tmp) {
            tmp = be16_to_cpu(map->size);
            smallest = i;
        }
    }

    /*
     * Coalesce adjacent freemap regions,
     * or replace the smallest region.
     */
    if ((before >= 0) || (after >= 0)) {
        if ((before >= 0) && (after >= 0)) {
            map = &hdr->freemap[before];
            be16_add_cpu(&map->size, entsize);
            be16_add_cpu(&map->size,
                 be16_to_cpu(hdr->freemap[after].size));
            hdr->freemap[after].base = 0;
            hdr->freemap[after].size = 0;
        } else if (before >= 0) {
            map = &hdr->freemap[before];
            be16_add_cpu(&map->size, entsize);
        } else {
            map = &hdr->freemap[after];
            /* both on-disk, don't endian flip twice */
            map->base = entry->nameidx;
            be16_add_cpu(&map->size, entsize);
        }
    } else {
        /*
         * Replace smallest region (if it is smaller than free'd entry)
         */
        map = &hdr->freemap[smallest];
        if (be16_to_cpu(map->size) < entsize) {
            map->base = cpu_to_be16(be16_to_cpu(entry->nameidx));
            map->size = cpu_to_be16(entsize);
        }
    }

    /*
     * Did we remove the first entry?
     */
    if (be16_to_cpu(entry->nameidx) == be16_to_cpu(hdr->firstused))
        smallest = 1;
    else
        smallest = 0;

    /*
     * Compress the remaining entries and zero out the removed stuff.
     */
    memset(xfs_attr_leaf_name(leaf, args->index), 0, entsize);
    be16_add_cpu(&hdr->usedbytes, -entsize);
    xfs_trans_log_buf(args->trans, bp,
         XFS_DA_LOGRANGE(leaf, xfs_attr_leaf_name(leaf, args->index),
                   entsize));

    tmp = (be16_to_cpu(hdr->count) - args->index)
                    * sizeof(xfs_attr_leaf_entry_t);
    memmove((char *)entry, (char *)(entry+1), tmp);
    be16_add_cpu(&hdr->count, -1);
    xfs_trans_log_buf(args->trans, bp,
        XFS_DA_LOGRANGE(leaf, entry, tmp + sizeof(*entry)));
    entry = &leaf->entries[be16_to_cpu(hdr->count)];
    memset((char *)entry, 0, sizeof(xfs_attr_leaf_entry_t));

    /*
     * If we removed the first entry, re-find the first used byte
     * in the name area.  Note that if the entry was the "firstused",
     * then we don't have a "hole" in our block resulting from
     * removing the name.
     */
    if (smallest) {
        tmp = XFS_LBSIZE(mp);
        entry = &leaf->entries[0];
        for (i = be16_to_cpu(hdr->count)-1; i >= 0; entry++, i--) {
            ASSERT(be16_to_cpu(entry->nameidx) >=
                   be16_to_cpu(hdr->firstused));
            ASSERT(be16_to_cpu(entry->nameidx) < XFS_LBSIZE(mp));

            if (be16_to_cpu(entry->nameidx) < tmp)
                tmp = be16_to_cpu(entry->nameidx);
        }
        hdr->firstused = cpu_to_be16(tmp);
        if (!hdr->firstused) {
            hdr->firstused = cpu_to_be16(
                    tmp - XFS_ATTR_LEAF_NAME_ALIGN);
        }
    } else {
        hdr->holes = 1;     /* mark as needing compaction */
    }
    xfs_trans_log_buf(args->trans, bp,
              XFS_DA_LOGRANGE(leaf, hdr, sizeof(*hdr)));

    /*
     * Check if leaf is less than 50% full, caller may want to
     * "join" the leaf with a sibling if so.
     */
    tmp  = sizeof(xfs_attr_leaf_hdr_t);
    tmp += be16_to_cpu(leaf->hdr.count) * sizeof(xfs_attr_leaf_entry_t);
    tmp += be16_to_cpu(leaf->hdr.usedbytes);
    return(tmp < mp->m_attr_magicpct); /* leaf is < 37% full */
}

/*
 * Move all the attribute list entries from drop_leaf into save_leaf.
 */
void
xfs_attr_leaf_unbalance(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
                       xfs_da_state_blk_t *save_blk)
{
    xfs_attr_leafblock_t *drop_leaf, *save_leaf, *tmp_leaf;
    xfs_attr_leaf_hdr_t *drop_hdr, *save_hdr, *tmp_hdr;
    xfs_mount_t *mp;
    char *tmpbuffer;

    trace_xfs_attr_leaf_unbalance(state->args);

    /*
     * Set up environment.
     */
    mp = state->mp;
    ASSERT(drop_blk->magic == XFS_ATTR_LEAF_MAGIC);
    ASSERT(save_blk->magic == XFS_ATTR_LEAF_MAGIC);
    drop_leaf = drop_blk->bp->b_addr;
    save_leaf = save_blk->bp->b_addr;
    ASSERT(drop_leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(save_leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    drop_hdr = &drop_leaf->hdr;
    save_hdr = &save_leaf->hdr;

    /*
     * Save last hashval from dying block for later Btree fixup.
     */
    drop_blk->hashval = be32_to_cpu(
        drop_leaf->entries[be16_to_cpu(drop_leaf->hdr.count)-1].hashval);

    /*
     * Check if we need a temp buffer, or can we do it in place.
     * Note that we don't check "leaf" for holes because we will
     * always be dropping it, toosmall() decided that for us already.
     */
    if (save_hdr->holes == 0) {
        /*
         * dest leaf has no holes, so we add there.  May need
         * to make some room in the entry array.
         */
        if (xfs_attr_leaf_order(save_blk->bp, drop_blk->bp)) {
            xfs_attr_leaf_moveents(drop_leaf, 0, save_leaf, 0,
                 be16_to_cpu(drop_hdr->count), mp);
        } else {
            xfs_attr_leaf_moveents(drop_leaf, 0, save_leaf,
                  be16_to_cpu(save_hdr->count),
                  be16_to_cpu(drop_hdr->count), mp);
        }
    } else {
        /*
         * Destination has holes, so we make a temporary copy
         * of the leaf and add them both to that.
         */
        tmpbuffer = kmem_alloc(state->blocksize, KM_SLEEP);
        ASSERT(tmpbuffer != NULL);
        memset(tmpbuffer, 0, state->blocksize);
        tmp_leaf = (xfs_attr_leafblock_t *)tmpbuffer;
        tmp_hdr = &tmp_leaf->hdr;
        tmp_hdr->info = save_hdr->info; /* struct copy */
        tmp_hdr->count = 0;
        tmp_hdr->firstused = cpu_to_be16(state->blocksize);
        if (!tmp_hdr->firstused) {
            tmp_hdr->firstused = cpu_to_be16(
                state->blocksize - XFS_ATTR_LEAF_NAME_ALIGN);
        }
        tmp_hdr->usedbytes = 0;
        if (xfs_attr_leaf_order(save_blk->bp, drop_blk->bp)) {
            xfs_attr_leaf_moveents(drop_leaf, 0, tmp_leaf, 0,
                be16_to_cpu(drop_hdr->count), mp);
            xfs_attr_leaf_moveents(save_leaf, 0, tmp_leaf,
                  be16_to_cpu(tmp_leaf->hdr.count),
                  be16_to_cpu(save_hdr->count), mp);
        } else {
            xfs_attr_leaf_moveents(save_leaf, 0, tmp_leaf, 0,
                be16_to_cpu(save_hdr->count), mp);
            xfs_attr_leaf_moveents(drop_leaf, 0, tmp_leaf,
                be16_to_cpu(tmp_leaf->hdr.count),
                be16_to_cpu(drop_hdr->count), mp);
        }
        memcpy((char *)save_leaf, (char *)tmp_leaf, state->blocksize);
        kmem_free(tmpbuffer);
    }

    xfs_trans_log_buf(state->args->trans, save_blk->bp, 0,
                       state->blocksize - 1);

    /*
     * Copy out last hashval in each block for B-tree code.
     */
    save_blk->hashval = be32_to_cpu(
        save_leaf->entries[be16_to_cpu(save_leaf->hdr.count)-1].hashval);
}

/*========================================================================
 * Routines used for finding things in the Btree.
 *========================================================================*/

/*
 * Look up a name in a leaf attribute list structure.
 * This is the internal routine, it uses the caller's buffer.
 *
 * Note that duplicate keys are allowed, but only check within the
 * current leaf node.  The Btree code must check in adjacent leaf nodes.
 *
 * Return in args->index the index into the entry[] array of either
 * the found entry, or where the entry should have been (insert before
 * that entry).
 *
 * Don't change the args->value unless we find the attribute.
 */
int
xfs_attr_leaf_lookup_int(
    struct xfs_buf  *bp,
    xfs_da_args_t   *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_local_t *name_loc;
    xfs_attr_leaf_name_remote_t *name_rmt;
    int probe, span;
    xfs_dahash_t hashval;

    trace_xfs_attr_leaf_lookup(args);

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(be16_to_cpu(leaf->hdr.count)
                    < (XFS_LBSIZE(args->dp->i_mount)/8));

    /*
     * Binary search.  (note: small blocks will skip this loop)
     */
    hashval = args->hashval;
    probe = span = be16_to_cpu(leaf->hdr.count) / 2;
    for (entry = &leaf->entries[probe]; span > 4;
           entry = &leaf->entries[probe]) {
        span /= 2;
        if (be32_to_cpu(entry->hashval) < hashval)
            probe += span;
        else if (be32_to_cpu(entry->hashval) > hashval)
            probe -= span;
        else
            break;
    }
    ASSERT((probe >= 0) &&
           (!leaf->hdr.count
           || (probe < be16_to_cpu(leaf->hdr.count))));
    ASSERT((span <= 4) || (be32_to_cpu(entry->hashval) == hashval));

    /*
     * Since we may have duplicate hashval's, find the first matching
     * hashval in the leaf.
     */
    while ((probe > 0) && (be32_to_cpu(entry->hashval) >= hashval)) {
        entry--;
        probe--;
    }
    while ((probe < be16_to_cpu(leaf->hdr.count)) &&
           (be32_to_cpu(entry->hashval) < hashval)) {
        entry++;
        probe++;
    }
    if ((probe == be16_to_cpu(leaf->hdr.count)) ||
        (be32_to_cpu(entry->hashval) != hashval)) {
        args->index = probe;
        return(XFS_ERROR(ENOATTR));
    }

    /*
     * Duplicate keys may be present, so search all of them for a match.
     */
    for (  ; (probe < be16_to_cpu(leaf->hdr.count)) &&
            (be32_to_cpu(entry->hashval) == hashval);
            entry++, probe++) {
/*
 * GROT: Add code to remove incomplete entries.
 */
        /*
         * If we are looking for INCOMPLETE entries, show only those.
         * If we are looking for complete entries, show only those.
         */
        if ((args->flags & XFS_ATTR_INCOMPLETE) !=
            (entry->flags & XFS_ATTR_INCOMPLETE)) {
            continue;
        }
        if (entry->flags & XFS_ATTR_LOCAL) {
            name_loc = xfs_attr_leaf_name_local(leaf, probe);
            if (name_loc->namelen != args->namelen)
                continue;
            if (memcmp(args->name, (char *)name_loc->nameval, args->namelen) != 0)
                continue;
            if (!xfs_attr_namesp_match(args->flags, entry->flags))
                continue;
            args->index = probe;
            return(XFS_ERROR(EEXIST));
        } else {
            name_rmt = xfs_attr_leaf_name_remote(leaf, probe);
            if (name_rmt->namelen != args->namelen)
                continue;
            if (memcmp(args->name, (char *)name_rmt->name,
                         args->namelen) != 0)
                continue;
            if (!xfs_attr_namesp_match(args->flags, entry->flags))
                continue;
            args->index = probe;
            args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
            args->rmtblkcnt = XFS_B_TO_FSB(args->dp->i_mount,
                           be32_to_cpu(name_rmt->valuelen));
            return(XFS_ERROR(EEXIST));
        }
    }
    args->index = probe;
    return(XFS_ERROR(ENOATTR));
}

/*
 * Get the value associated with an attribute name from a leaf attribute
 * list structure.
 */
int
xfs_attr_leaf_getvalue(
    struct xfs_buf  *bp,
    xfs_da_args_t   *args)
{
    int valuelen;
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_local_t *name_loc;
    xfs_attr_leaf_name_remote_t *name_rmt;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(be16_to_cpu(leaf->hdr.count)
                    < (XFS_LBSIZE(args->dp->i_mount)/8));
    ASSERT(args->index < be16_to_cpu(leaf->hdr.count));

    entry = &leaf->entries[args->index];
    if (entry->flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf, args->index);
        ASSERT(name_loc->namelen == args->namelen);
        ASSERT(memcmp(args->name, name_loc->nameval, args->namelen) == 0);
        valuelen = be16_to_cpu(name_loc->valuelen);
        if (args->flags & ATTR_KERNOVAL) {
            args->valuelen = valuelen;
            return(0);
        }
        if (args->valuelen < valuelen) {
            args->valuelen = valuelen;
            return(XFS_ERROR(ERANGE));
        }
        args->valuelen = valuelen;
        memcpy(args->value, &name_loc->nameval[args->namelen], valuelen);
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf, args->index);
        ASSERT(name_rmt->namelen == args->namelen);
        ASSERT(memcmp(args->name, name_rmt->name, args->namelen) == 0);
        valuelen = be32_to_cpu(name_rmt->valuelen);
        args->rmtblkno = be32_to_cpu(name_rmt->valueblk);
        args->rmtblkcnt = XFS_B_TO_FSB(args->dp->i_mount, valuelen);
        if (args->flags & ATTR_KERNOVAL) {
            args->valuelen = valuelen;
            return(0);
        }
        if (args->valuelen < valuelen) {
            args->valuelen = valuelen;
            return(XFS_ERROR(ERANGE));
        }
        args->valuelen = valuelen;
    }
    return(0);
}

/*========================================================================
 * Utility routines.
 *========================================================================*/

/*
 * Move the indicated entries from one leaf to another.
 * NOTE: this routine modifies both source and destination leaves.
 */
/*ARGSUSED*/
STATIC void
xfs_attr_leaf_moveents(xfs_attr_leafblock_t *leaf_s, int start_s,
            xfs_attr_leafblock_t *leaf_d, int start_d,
            int count, xfs_mount_t *mp)
{
    xfs_attr_leaf_hdr_t *hdr_s, *hdr_d;
    xfs_attr_leaf_entry_t *entry_s, *entry_d;
    int desti, tmp, i;

    /*
     * Check for nothing to do.
     */
    if (count == 0)
        return;

    /*
     * Set up environment.
     */
    ASSERT(leaf_s->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(leaf_d->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    hdr_s = &leaf_s->hdr;
    hdr_d = &leaf_d->hdr;
    ASSERT((be16_to_cpu(hdr_s->count) > 0) &&
           (be16_to_cpu(hdr_s->count) < (XFS_LBSIZE(mp)/8)));
    ASSERT(be16_to_cpu(hdr_s->firstused) >=
        ((be16_to_cpu(hdr_s->count)
                    * sizeof(*entry_s))+sizeof(*hdr_s)));
    ASSERT(be16_to_cpu(hdr_d->count) < (XFS_LBSIZE(mp)/8));
    ASSERT(be16_to_cpu(hdr_d->firstused) >=
        ((be16_to_cpu(hdr_d->count)
                    * sizeof(*entry_d))+sizeof(*hdr_d)));

    ASSERT(start_s < be16_to_cpu(hdr_s->count));
    ASSERT(start_d <= be16_to_cpu(hdr_d->count));
    ASSERT(count <= be16_to_cpu(hdr_s->count));

    /*
     * Move the entries in the destination leaf up to make a hole?
     */
    if (start_d < be16_to_cpu(hdr_d->count)) {
        tmp  = be16_to_cpu(hdr_d->count) - start_d;
        tmp *= sizeof(xfs_attr_leaf_entry_t);
        entry_s = &leaf_d->entries[start_d];
        entry_d = &leaf_d->entries[start_d + count];
        memmove((char *)entry_d, (char *)entry_s, tmp);
    }

    /*
     * Copy all entry's in the same (sorted) order,
     * but allocate attribute info packed and in sequence.
     */
    entry_s = &leaf_s->entries[start_s];
    entry_d = &leaf_d->entries[start_d];
    desti = start_d;
    for (i = 0; i < count; entry_s++, entry_d++, desti++, i++) {
        ASSERT(be16_to_cpu(entry_s->nameidx)
                >= be16_to_cpu(hdr_s->firstused));
        tmp = xfs_attr_leaf_entsize(leaf_s, start_s + i);
#ifdef GROT
        /*
         * Code to drop INCOMPLETE entries.  Difficult to use as we
         * may also need to change the insertion index.  Code turned
         * off for 6.2, should be revisited later.
         */
        if (entry_s->flags & XFS_ATTR_INCOMPLETE) { /* skip partials? */
            memset(xfs_attr_leaf_name(leaf_s, start_s + i), 0, tmp);
            be16_add_cpu(&hdr_s->usedbytes, -tmp);
            be16_add_cpu(&hdr_s->count, -1);
            entry_d--;  /* to compensate for ++ in loop hdr */
            desti--;
            if ((start_s + i) < offset)
                result++;   /* insertion index adjustment */
        } else {
#endif /* GROT */
            be16_add_cpu(&hdr_d->firstused, -tmp);
            /* both on-disk, don't endian flip twice */
            entry_d->hashval = entry_s->hashval;
            /* both on-disk, don't endian flip twice */
            entry_d->nameidx = hdr_d->firstused;
            entry_d->flags = entry_s->flags;
            ASSERT(be16_to_cpu(entry_d->nameidx) + tmp
                            <= XFS_LBSIZE(mp));
            memmove(xfs_attr_leaf_name(leaf_d, desti),
                xfs_attr_leaf_name(leaf_s, start_s + i), tmp);
            ASSERT(be16_to_cpu(entry_s->nameidx) + tmp
                            <= XFS_LBSIZE(mp));
            memset(xfs_attr_leaf_name(leaf_s, start_s + i), 0, tmp);
            be16_add_cpu(&hdr_s->usedbytes, -tmp);
            be16_add_cpu(&hdr_d->usedbytes, tmp);
            be16_add_cpu(&hdr_s->count, -1);
            be16_add_cpu(&hdr_d->count, 1);
            tmp = be16_to_cpu(hdr_d->count)
                        * sizeof(xfs_attr_leaf_entry_t)
                        + sizeof(xfs_attr_leaf_hdr_t);
            ASSERT(be16_to_cpu(hdr_d->firstused) >= tmp);
#ifdef GROT
        }
#endif /* GROT */
    }

    /*
     * Zero out the entries we just copied.
     */
    if (start_s == be16_to_cpu(hdr_s->count)) {
        tmp = count * sizeof(xfs_attr_leaf_entry_t);
        entry_s = &leaf_s->entries[start_s];
        ASSERT(((char *)entry_s + tmp) <=
               ((char *)leaf_s + XFS_LBSIZE(mp)));
        memset((char *)entry_s, 0, tmp);
    } else {
        /*
         * Move the remaining entries down to fill the hole,
         * then zero the entries at the top.
         */
        tmp  = be16_to_cpu(hdr_s->count) - count;
        tmp *= sizeof(xfs_attr_leaf_entry_t);
        entry_s = &leaf_s->entries[start_s + count];
        entry_d = &leaf_s->entries[start_s];
        memmove((char *)entry_d, (char *)entry_s, tmp);

        tmp = count * sizeof(xfs_attr_leaf_entry_t);
        entry_s = &leaf_s->entries[be16_to_cpu(hdr_s->count)];
        ASSERT(((char *)entry_s + tmp) <=
               ((char *)leaf_s + XFS_LBSIZE(mp)));
        memset((char *)entry_s, 0, tmp);
    }

    /*
     * Fill in the freemap information
     */
    hdr_d->freemap[0].base = cpu_to_be16(sizeof(xfs_attr_leaf_hdr_t));
    be16_add_cpu(&hdr_d->freemap[0].base, be16_to_cpu(hdr_d->count) *
            sizeof(xfs_attr_leaf_entry_t));
    hdr_d->freemap[0].size = cpu_to_be16(be16_to_cpu(hdr_d->firstused)
                  - be16_to_cpu(hdr_d->freemap[0].base));
    hdr_d->freemap[1].base = 0;
    hdr_d->freemap[2].base = 0;
    hdr_d->freemap[1].size = 0;
    hdr_d->freemap[2].size = 0;
    hdr_s->holes = 1;   /* leaf may not be compact */
}

/*
 * Compare two leaf blocks "order".
 * Return 0 unless leaf2 should go before leaf1.
 */
int
xfs_attr_leaf_order(
    struct xfs_buf  *leaf1_bp,
    struct xfs_buf  *leaf2_bp)
{
    xfs_attr_leafblock_t *leaf1, *leaf2;

    leaf1 = leaf1_bp->b_addr;
    leaf2 = leaf2_bp->b_addr;
    ASSERT((leaf1->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC)) &&
           (leaf2->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC)));
    if ((be16_to_cpu(leaf1->hdr.count) > 0) &&
        (be16_to_cpu(leaf2->hdr.count) > 0) &&
        ((be32_to_cpu(leaf2->entries[0].hashval) <
          be32_to_cpu(leaf1->entries[0].hashval)) ||
         (be32_to_cpu(leaf2->entries[
            be16_to_cpu(leaf2->hdr.count)-1].hashval) <
          be32_to_cpu(leaf1->entries[
            be16_to_cpu(leaf1->hdr.count)-1].hashval)))) {
        return(1);
    }
    return(0);
}

/*
 * Pick up the last hashvalue from a leaf block.
 */
xfs_dahash_t
xfs_attr_leaf_lasthash(
    struct xfs_buf  *bp,
    int     *count)
{
    xfs_attr_leafblock_t *leaf;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    if (count)
        *count = be16_to_cpu(leaf->hdr.count);
    if (!leaf->hdr.count)
        return(0);
    return be32_to_cpu(leaf->entries[be16_to_cpu(leaf->hdr.count)-1].hashval);
}

/*
 * Calculate the number of bytes used to store the indicated attribute
 * (whether local or remote only calculate bytes in this block).
 */
STATIC int
xfs_attr_leaf_entsize(xfs_attr_leafblock_t *leaf, int index)
{
    xfs_attr_leaf_name_local_t *name_loc;
    xfs_attr_leaf_name_remote_t *name_rmt;
    int size;

    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    if (leaf->entries[index].flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf, index);
        size = xfs_attr_leaf_entsize_local(name_loc->namelen,
                           be16_to_cpu(name_loc->valuelen));
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf, index);
        size = xfs_attr_leaf_entsize_remote(name_rmt->namelen);
    }
    return(size);
}

/*
 * Calculate the number of bytes that would be required to store the new
 * attribute (whether local or remote only calculate bytes in this block).
 * This routine decides as a side effect whether the attribute will be
 * a "local" or a "remote" attribute.
 */
int
xfs_attr_leaf_newentsize(int namelen, int valuelen, int blocksize, int *local)
{
    int size;

    size = xfs_attr_leaf_entsize_local(namelen, valuelen);
    if (size < xfs_attr_leaf_entsize_local_max(blocksize)) {
        if (local) {
            *local = 1;
        }
    } else {
        size = xfs_attr_leaf_entsize_remote(namelen);
        if (local) {
            *local = 0;
        }
    }
    return(size);
}

/*
 * Copy out attribute list entries for attr_list(), for leaf attribute lists.
 */
int
xfs_attr_leaf_list_int(
    struct xfs_buf      *bp,
    xfs_attr_list_context_t *context)
{
    attrlist_cursor_kern_t *cursor;
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    int retval, i;

    ASSERT(bp != NULL);
    leaf = bp->b_addr;
    cursor = context->cursor;
    cursor->initted = 1;

    trace_xfs_attr_list_leaf(context);

    /*
     * Re-find our place in the leaf block if this is a new syscall.
     */
    if (context->resynch) {
        entry = &leaf->entries[0];
        for (i = 0; i < be16_to_cpu(leaf->hdr.count); entry++, i++) {
            if (be32_to_cpu(entry->hashval) == cursor->hashval) {
                if (cursor->offset == context->dupcnt) {
                    context->dupcnt = 0;
                    break;
                }
                context->dupcnt++;
            } else if (be32_to_cpu(entry->hashval) >
                    cursor->hashval) {
                context->dupcnt = 0;
                break;
            }
        }
        if (i == be16_to_cpu(leaf->hdr.count)) {
            trace_xfs_attr_list_notfound(context);
            return(0);
        }
    } else {
        entry = &leaf->entries[0];
        i = 0;
    }
    context->resynch = 0;

    /*
     * We have found our place, start copying out the new attributes.
     */
    retval = 0;
    for (  ; (i < be16_to_cpu(leaf->hdr.count)); entry++, i++) {
        if (be32_to_cpu(entry->hashval) != cursor->hashval) {
            cursor->hashval = be32_to_cpu(entry->hashval);
            cursor->offset = 0;
        }

        if (entry->flags & XFS_ATTR_INCOMPLETE)
            continue;       /* skip incomplete entries */

        if (entry->flags & XFS_ATTR_LOCAL) {
            xfs_attr_leaf_name_local_t *name_loc =
                xfs_attr_leaf_name_local(leaf, i);

            retval = context->put_listent(context,
                        entry->flags,
                        name_loc->nameval,
                        (int)name_loc->namelen,
                        be16_to_cpu(name_loc->valuelen),
                        &name_loc->nameval[name_loc->namelen]);
            if (retval)
                return retval;
        } else {
            xfs_attr_leaf_name_remote_t *name_rmt =
                xfs_attr_leaf_name_remote(leaf, i);

            int valuelen = be32_to_cpu(name_rmt->valuelen);

            if (context->put_value) {
                xfs_da_args_t args;

                memset((char *)&args, 0, sizeof(args));
                args.dp = context->dp;
                args.whichfork = XFS_ATTR_FORK;
                args.valuelen = valuelen;
                args.value = kmem_alloc(valuelen, KM_SLEEP | KM_NOFS);
                args.rmtblkno = be32_to_cpu(name_rmt->valueblk);
                args.rmtblkcnt = XFS_B_TO_FSB(args.dp->i_mount, valuelen);
                retval = xfs_attr_rmtval_get(&args);
                if (retval)
                    return retval;
                retval = context->put_listent(context,
                        entry->flags,
                        name_rmt->name,
                        (int)name_rmt->namelen,
                        valuelen,
                        args.value);
                kmem_free(args.value);
            } else {
                retval = context->put_listent(context,
                        entry->flags,
                        name_rmt->name,
                        (int)name_rmt->namelen,
                        valuelen,
                        NULL);
            }
            if (retval)
                return retval;
        }
        if (context->seen_enough)
            break;
        cursor->offset++;
    }
    trace_xfs_attr_list_leaf_end(context);
    return(retval);
}


/*========================================================================
 * Manage the INCOMPLETE flag in a leaf entry
 *========================================================================*/

/*
 * Clear the INCOMPLETE flag on an entry in a leaf block.
 */
int
xfs_attr_leaf_clearflag(xfs_da_args_t *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_remote_t *name_rmt;
    struct xfs_buf *bp;
    int error;
#ifdef DEBUG
    xfs_attr_leaf_name_local_t *name_loc;
    int namelen;
    char *name;
#endif /* DEBUG */

    trace_xfs_attr_leaf_clearflag(args);
    /*
     * Set up the operation.
     */
    error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
                         XFS_ATTR_FORK);
    if (error) {
        return(error);
    }
    ASSERT(bp != NULL);

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(args->index < be16_to_cpu(leaf->hdr.count));
    ASSERT(args->index >= 0);
    entry = &leaf->entries[ args->index ];
    ASSERT(entry->flags & XFS_ATTR_INCOMPLETE);

#ifdef DEBUG
    if (entry->flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf, args->index);
        namelen = name_loc->namelen;
        name = (char *)name_loc->nameval;
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf, args->index);
        namelen = name_rmt->namelen;
        name = (char *)name_rmt->name;
    }
    ASSERT(be32_to_cpu(entry->hashval) == args->hashval);
    ASSERT(namelen == args->namelen);
    ASSERT(memcmp(name, args->name, namelen) == 0);
#endif /* DEBUG */

    entry->flags &= ~XFS_ATTR_INCOMPLETE;
    xfs_trans_log_buf(args->trans, bp,
             XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));

    if (args->rmtblkno) {
        ASSERT((entry->flags & XFS_ATTR_LOCAL) == 0);
        name_rmt = xfs_attr_leaf_name_remote(leaf, args->index);
        name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
        name_rmt->valuelen = cpu_to_be32(args->valuelen);
        xfs_trans_log_buf(args->trans, bp,
             XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
    }

    /*
     * Commit the flag value change and start the next trans in series.
     */
    return xfs_trans_roll(&args->trans, args->dp);
}

/*
 * Set the INCOMPLETE flag on an entry in a leaf block.
 */
int
xfs_attr_leaf_setflag(xfs_da_args_t *args)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_remote_t *name_rmt;
    struct xfs_buf *bp;
    int error;

    trace_xfs_attr_leaf_setflag(args);

    /*
     * Set up the operation.
     */
    error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp,
                         XFS_ATTR_FORK);
    if (error) {
        return(error);
    }
    ASSERT(bp != NULL);

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(args->index < be16_to_cpu(leaf->hdr.count));
    ASSERT(args->index >= 0);
    entry = &leaf->entries[ args->index ];

    ASSERT((entry->flags & XFS_ATTR_INCOMPLETE) == 0);
    entry->flags |= XFS_ATTR_INCOMPLETE;
    xfs_trans_log_buf(args->trans, bp,
            XFS_DA_LOGRANGE(leaf, entry, sizeof(*entry)));
    if ((entry->flags & XFS_ATTR_LOCAL) == 0) {
        name_rmt = xfs_attr_leaf_name_remote(leaf, args->index);
        name_rmt->valueblk = 0;
        name_rmt->valuelen = 0;
        xfs_trans_log_buf(args->trans, bp,
             XFS_DA_LOGRANGE(leaf, name_rmt, sizeof(*name_rmt)));
    }

    /*
     * Commit the flag value change and start the next trans in series.
     */
    return xfs_trans_roll(&args->trans, args->dp);
}

/*
 * In a single transaction, clear the INCOMPLETE flag on the leaf entry
 * given by args->blkno/index and set the INCOMPLETE flag on the leaf
 * entry given by args->blkno2/index2.
 *
 * Note that they could be in different blocks, or in the same block.
 */
int
xfs_attr_leaf_flipflags(xfs_da_args_t *args)
{
    xfs_attr_leafblock_t *leaf1, *leaf2;
    xfs_attr_leaf_entry_t *entry1, *entry2;
    xfs_attr_leaf_name_remote_t *name_rmt;
    struct xfs_buf *bp1, *bp2;
    int error;
#ifdef DEBUG
    xfs_attr_leaf_name_local_t *name_loc;
    int namelen1, namelen2;
    char *name1, *name2;
#endif /* DEBUG */

    trace_xfs_attr_leaf_flipflags(args);

    /*
     * Read the block containing the "old" attr
     */
    error = xfs_da_read_buf(args->trans, args->dp, args->blkno, -1, &bp1,
                         XFS_ATTR_FORK);
    if (error) {
        return(error);
    }
    ASSERT(bp1 != NULL);

    /*
     * Read the block containing the "new" attr, if it is different
     */
    if (args->blkno2 != args->blkno) {
        error = xfs_da_read_buf(args->trans, args->dp, args->blkno2,
                    -1, &bp2, XFS_ATTR_FORK);
        if (error) {
            return(error);
        }
        ASSERT(bp2 != NULL);
    } else {
        bp2 = bp1;
    }

    leaf1 = bp1->b_addr;
    ASSERT(leaf1->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(args->index < be16_to_cpu(leaf1->hdr.count));
    ASSERT(args->index >= 0);
    entry1 = &leaf1->entries[ args->index ];

    leaf2 = bp2->b_addr;
    ASSERT(leaf2->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));
    ASSERT(args->index2 < be16_to_cpu(leaf2->hdr.count));
    ASSERT(args->index2 >= 0);
    entry2 = &leaf2->entries[ args->index2 ];

#ifdef DEBUG
    if (entry1->flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf1, args->index);
        namelen1 = name_loc->namelen;
        name1 = (char *)name_loc->nameval;
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf1, args->index);
        namelen1 = name_rmt->namelen;
        name1 = (char *)name_rmt->name;
    }
    if (entry2->flags & XFS_ATTR_LOCAL) {
        name_loc = xfs_attr_leaf_name_local(leaf2, args->index2);
        namelen2 = name_loc->namelen;
        name2 = (char *)name_loc->nameval;
    } else {
        name_rmt = xfs_attr_leaf_name_remote(leaf2, args->index2);
        namelen2 = name_rmt->namelen;
        name2 = (char *)name_rmt->name;
    }
    ASSERT(be32_to_cpu(entry1->hashval) == be32_to_cpu(entry2->hashval));
    ASSERT(namelen1 == namelen2);
    ASSERT(memcmp(name1, name2, namelen1) == 0);
#endif /* DEBUG */

    ASSERT(entry1->flags & XFS_ATTR_INCOMPLETE);
    ASSERT((entry2->flags & XFS_ATTR_INCOMPLETE) == 0);

    entry1->flags &= ~XFS_ATTR_INCOMPLETE;
    xfs_trans_log_buf(args->trans, bp1,
              XFS_DA_LOGRANGE(leaf1, entry1, sizeof(*entry1)));
    if (args->rmtblkno) {
        ASSERT((entry1->flags & XFS_ATTR_LOCAL) == 0);
        name_rmt = xfs_attr_leaf_name_remote(leaf1, args->index);
        name_rmt->valueblk = cpu_to_be32(args->rmtblkno);
        name_rmt->valuelen = cpu_to_be32(args->valuelen);
        xfs_trans_log_buf(args->trans, bp1,
             XFS_DA_LOGRANGE(leaf1, name_rmt, sizeof(*name_rmt)));
    }

    entry2->flags |= XFS_ATTR_INCOMPLETE;
    xfs_trans_log_buf(args->trans, bp2,
              XFS_DA_LOGRANGE(leaf2, entry2, sizeof(*entry2)));
    if ((entry2->flags & XFS_ATTR_LOCAL) == 0) {
        name_rmt = xfs_attr_leaf_name_remote(leaf2, args->index2);
        name_rmt->valueblk = 0;
        name_rmt->valuelen = 0;
        xfs_trans_log_buf(args->trans, bp2,
             XFS_DA_LOGRANGE(leaf2, name_rmt, sizeof(*name_rmt)));
    }

    /*
     * Commit the flag value change and start the next trans in series.
     */
    error = xfs_trans_roll(&args->trans, args->dp);

    return(error);
}

/*========================================================================
 * Indiscriminately delete the entire attribute fork
 *========================================================================*/

/*
 * Recurse (gasp!) through the attribute nodes until we find leaves.
 * We're doing a depth-first traversal in order to invalidate everything.
 */
int
xfs_attr_root_inactive(xfs_trans_t **trans, xfs_inode_t *dp)
{
    xfs_da_blkinfo_t *info;
    xfs_daddr_t blkno;
    struct xfs_buf *bp;
    int error;

    /*
     * Read block 0 to see what we have to work with.
     * We only get here if we have extents, since we remove
     * the extents in reverse order the extent containing
     * block 0 must still be there.
     */
    error = xfs_da_read_buf(*trans, dp, 0, -1, &bp, XFS_ATTR_FORK);
    if (error)
        return(error);
    blkno = XFS_BUF_ADDR(bp);

    /*
     * Invalidate the tree, even if the "tree" is only a single leaf block.
     * This is a depth-first traversal!
     */
    info = bp->b_addr;
    if (info->magic == cpu_to_be16(XFS_DA_NODE_MAGIC)) {
        error = xfs_attr_node_inactive(trans, dp, bp, 1);
    } else if (info->magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC)) {
        error = xfs_attr_leaf_inactive(trans, dp, bp);
    } else {
        error = XFS_ERROR(EIO);
        xfs_trans_brelse(*trans, bp);
    }
    if (error)
        return(error);

    /*
     * Invalidate the incore copy of the root block.
     */
    error = xfs_da_get_buf(*trans, dp, 0, blkno, &bp, XFS_ATTR_FORK);
    if (error)
        return(error);
    xfs_trans_binval(*trans, bp);   /* remove from cache */
    /*
     * Commit the invalidate and start the next transaction.
     */
    error = xfs_trans_roll(trans, dp);

    return (error);
}

/*
 * Recurse (gasp!) through the attribute nodes until we find leaves.
 * We're doing a depth-first traversal in order to invalidate everything.
 */
STATIC int
xfs_attr_node_inactive(
    struct xfs_trans **trans,
    struct xfs_inode *dp,
    struct xfs_buf  *bp,
    int     level)
{
    xfs_da_blkinfo_t *info;
    xfs_da_intnode_t *node;
    xfs_dablk_t child_fsb;
    xfs_daddr_t parent_blkno, child_blkno;
    int error, count, i;
    struct xfs_buf *child_bp;

    /*
     * Since this code is recursive (gasp!) we must protect ourselves.
     */
    if (level > XFS_DA_NODE_MAXDEPTH) {
        xfs_trans_brelse(*trans, bp);   /* no locks for later trans */
        return(XFS_ERROR(EIO));
    }

    node = bp->b_addr;
    ASSERT(node->hdr.info.magic == cpu_to_be16(XFS_DA_NODE_MAGIC));
    parent_blkno = XFS_BUF_ADDR(bp);    /* save for re-read later */
    count = be16_to_cpu(node->hdr.count);
    if (!count) {
        xfs_trans_brelse(*trans, bp);
        return(0);
    }
    child_fsb = be32_to_cpu(node->btree[0].before);
    xfs_trans_brelse(*trans, bp);   /* no locks for later trans */

    /*
     * If this is the node level just above the leaves, simply loop
     * over the leaves removing all of them.  If this is higher up
     * in the tree, recurse downward.
     */
    for (i = 0; i < count; i++) {
        /*
         * Read the subsidiary block to see what we have to work with.
         * Don't do this in a transaction.  This is a depth-first
         * traversal of the tree so we may deal with many blocks
         * before we come back to this one.
         */
        error = xfs_da_read_buf(*trans, dp, child_fsb, -2, &child_bp,
                        XFS_ATTR_FORK);
        if (error)
            return(error);
        if (child_bp) {
                        /* save for re-read later */
            child_blkno = XFS_BUF_ADDR(child_bp);

            /*
             * Invalidate the subtree, however we have to.
             */
            info = child_bp->b_addr;
            if (info->magic == cpu_to_be16(XFS_DA_NODE_MAGIC)) {
                error = xfs_attr_node_inactive(trans, dp,
                        child_bp, level+1);
            } else if (info->magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC)) {
                error = xfs_attr_leaf_inactive(trans, dp,
                        child_bp);
            } else {
                error = XFS_ERROR(EIO);
                xfs_trans_brelse(*trans, child_bp);
            }
            if (error)
                return(error);

            /*
             * Remove the subsidiary block from the cache
             * and from the log.
             */
            error = xfs_da_get_buf(*trans, dp, 0, child_blkno,
                &child_bp, XFS_ATTR_FORK);
            if (error)
                return(error);
            xfs_trans_binval(*trans, child_bp);
        }

        /*
         * If we're not done, re-read the parent to get the next
         * child block number.
         */
        if ((i+1) < count) {
            error = xfs_da_read_buf(*trans, dp, 0, parent_blkno,
                &bp, XFS_ATTR_FORK);
            if (error)
                return(error);
            child_fsb = be32_to_cpu(node->btree[i+1].before);
            xfs_trans_brelse(*trans, bp);
        }
        /*
         * Atomically commit the whole invalidate stuff.
         */
        error = xfs_trans_roll(trans, dp);
        if (error)
            return (error);
    }

    return(0);
}

/*
 * Invalidate all of the "remote" value regions pointed to by a particular
 * leaf block.
 * Note that we must release the lock on the buffer so that we are not
 * caught holding something that the logging code wants to flush to disk.
 */
STATIC int
xfs_attr_leaf_inactive(
    struct xfs_trans **trans,
    struct xfs_inode *dp,
    struct xfs_buf  *bp)
{
    xfs_attr_leafblock_t *leaf;
    xfs_attr_leaf_entry_t *entry;
    xfs_attr_leaf_name_remote_t *name_rmt;
    xfs_attr_inactive_list_t *list, *lp;
    int error, count, size, tmp, i;

    leaf = bp->b_addr;
    ASSERT(leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC));

    /*
     * Count the number of "remote" value extents.
     */
    count = 0;
    entry = &leaf->entries[0];
    for (i = 0; i < be16_to_cpu(leaf->hdr.count); entry++, i++) {
        if (be16_to_cpu(entry->nameidx) &&
            ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
            name_rmt = xfs_attr_leaf_name_remote(leaf, i);
            if (name_rmt->valueblk)
                count++;
        }
    }

    /*
     * If there are no "remote" values, we're done.
     */
    if (count == 0) {
        xfs_trans_brelse(*trans, bp);
        return(0);
    }

    /*
     * Allocate storage for a list of all the "remote" value extents.
     */
    size = count * sizeof(xfs_attr_inactive_list_t);
    list = (xfs_attr_inactive_list_t *)kmem_alloc(size, KM_SLEEP);

    /*
     * Identify each of the "remote" value extents.
     */
    lp = list;
    entry = &leaf->entries[0];
    for (i = 0; i < be16_to_cpu(leaf->hdr.count); entry++, i++) {
        if (be16_to_cpu(entry->nameidx) &&
            ((entry->flags & XFS_ATTR_LOCAL) == 0)) {
            name_rmt = xfs_attr_leaf_name_remote(leaf, i);
            if (name_rmt->valueblk) {
                lp->valueblk = be32_to_cpu(name_rmt->valueblk);
                lp->valuelen = XFS_B_TO_FSB(dp->i_mount,
                            be32_to_cpu(name_rmt->valuelen));
                lp++;
            }
        }
    }
    xfs_trans_brelse(*trans, bp);   /* unlock for trans. in freextent() */

    /*
     * Invalidate each of the "remote" value extents.
     */
    error = 0;
    for (lp = list, i = 0; i < count; i++, lp++) {
        tmp = xfs_attr_leaf_freextent(trans, dp,
                lp->valueblk, lp->valuelen);

        if (error == 0)
            error = tmp;    /* save only the 1st errno */
    }

    kmem_free((xfs_caddr_t)list);
    return(error);
}

/*
 * Look at all the extents for this logical region,
 * invalidate any buffers that are incore/in transactions.
 */
STATIC int
xfs_attr_leaf_freextent(xfs_trans_t **trans, xfs_inode_t *dp,
                    xfs_dablk_t blkno, int blkcnt)
{
    xfs_bmbt_irec_t map;
    xfs_dablk_t tblkno;
    int tblkcnt, dblkcnt, nmap, error;
    xfs_daddr_t dblkno;
    xfs_buf_t *bp;

    /*
     * Roll through the "value", invalidating the attribute value's
     * blocks.
     */
    tblkno = blkno;
    tblkcnt = blkcnt;
    while (tblkcnt > 0) {
        /*
         * Try to remember where we decided to put the value.
         */
        nmap = 1;
        error = xfs_bmapi_read(dp, (xfs_fileoff_t)tblkno, tblkcnt,
                       &map, &nmap, XFS_BMAPI_ATTRFORK);
        if (error) {
            return(error);
        }
        ASSERT(nmap == 1);
        ASSERT(map.br_startblock != DELAYSTARTBLOCK);

        /*
         * If it's a hole, these are already unmapped
         * so there's nothing to invalidate.
         */
        if (map.br_startblock != HOLESTARTBLOCK) {

            dblkno = XFS_FSB_TO_DADDR(dp->i_mount,
                          map.br_startblock);
            dblkcnt = XFS_FSB_TO_BB(dp->i_mount,
                        map.br_blockcount);
            bp = xfs_trans_get_buf(*trans,
                    dp->i_mount->m_ddev_targp,
                    dblkno, dblkcnt, 0);
            if (!bp)
                return ENOMEM;
            xfs_trans_binval(*trans, bp);
            /*
             * Roll to next transaction.
             */
            error = xfs_trans_roll(trans, dp);
            if (error)
                return (error);
        }

        tblkno += map.br_blockcount;
        tblkcnt -= map.br_blockcount;
    }

    return(0);
}