xfs_attr_sf.h

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/*
 * Copyright (c) 2000,2002,2005 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
 */
#ifndef __XFS_ATTR_SF_H__
#define __XFS_ATTR_SF_H__

/*
 * Attribute storage when stored inside the inode.
 *
 * Small attribute lists are packed as tightly as possible so as
 * to fit into the literal area of the inode.
 */

/*
 * Entries are packed toward the top as tight as possible.
 */
typedef struct xfs_attr_shortform {
    struct xfs_attr_sf_hdr {    /* constant-structure header block */
        __be16  totsize;    /* total bytes in shortform list */
        __u8    count;  /* count of active entries */
    } hdr;
    struct xfs_attr_sf_entry {
        __uint8_t namelen;  /* actual length of name (no NULL) */
        __uint8_t valuelen; /* actual length of value (no NULL) */
        __uint8_t flags;    /* flags bits (see xfs_attr_leaf.h) */
        __uint8_t nameval[1];   /* name & value bytes concatenated */
    } list[1];          /* variable sized array */
} xfs_attr_shortform_t;
typedef struct xfs_attr_sf_hdr xfs_attr_sf_hdr_t;
typedef struct xfs_attr_sf_entry xfs_attr_sf_entry_t;

/*
 * We generate this then sort it, attr_list() must return things in hash-order.
 */
typedef struct xfs_attr_sf_sort {
    __uint8_t   entno;      /* entry number in original list */
    __uint8_t   namelen;    /* length of name value (no null) */
    __uint8_t   valuelen;   /* length of value */
    __uint8_t   flags;      /* flags bits (see xfs_attr_leaf.h) */
    xfs_dahash_t    hash;       /* this entry's hash value */
    unsigned char   *name;      /* name value, pointer into buffer */
} xfs_attr_sf_sort_t;

#define XFS_ATTR_SF_ENTSIZE_BYNAME(nlen,vlen)   /* space name/value uses */ \
    (((int)sizeof(xfs_attr_sf_entry_t)-1 + (nlen)+(vlen)))
#define XFS_ATTR_SF_ENTSIZE_MAX         /* max space for name&value */ \
    ((1 << (NBBY*(int)sizeof(__uint8_t))) - 1)
#define XFS_ATTR_SF_ENTSIZE(sfep)       /* space an entry uses */ \
    ((int)sizeof(xfs_attr_sf_entry_t)-1 + (sfep)->namelen+(sfep)->valuelen)
#define XFS_ATTR_SF_NEXTENTRY(sfep)     /* next entry in struct */ \
    ((xfs_attr_sf_entry_t *)((char *)(sfep) + XFS_ATTR_SF_ENTSIZE(sfep)))
#define XFS_ATTR_SF_TOTSIZE(dp)         /* total space in use */ \
    (be16_to_cpu(((xfs_attr_shortform_t *)  \
        ((dp)->i_afp->if_u1.if_data))->hdr.totsize))

#endif  /* __XFS_ATTR_SF_H__ */