root/usr/src/uts/common/sys/fs/decomp.h
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef _SYS_DECOMP_H
#define _SYS_DECOMP_H

#ifdef  __cplusplus
extern "C" {
#endif

#define CH_MAGIC_ZLIB   0x5a636d70      /* ZLIB compression */
#define CH_MAGIC_GZIP   0x8B1F          /* GZIP compression */

#define CH_VERSION      1

#define CH_ALG_ZLIB     1

struct comphdr {
        uint64_t        ch_magic;
        uint64_t        ch_version;
        uint64_t        ch_algorithm;
        uint64_t        ch_fsize;
        uint64_t        ch_blksize;
        uint64_t        ch_blkmap[1];
};

#define ZMAXBUF(n)      ((n) + ((n) / 1000) + 12)

#ifdef  _KERNEL

struct dcnode {
        struct vnode    *dc_vp;
        struct vnode    *dc_subvp;
        struct kmem_cache *dc_bufcache;
        kmutex_t        dc_lock;
        struct dcnode   *dc_hash;
        struct dcnode   *dc_lrunext;
        struct dcnode   *dc_lruprev;
        struct comphdr  *dc_hdr;
        size_t          dc_hdrsize;
        size_t          dc_zmax;
        int             dc_mapcnt;
};

#define VTODC(vp)       ((struct dcnode *)(vp)->v_data)
#define DCTOV(dp)       ((dp)->dc_vp)

struct vnode    *decompvp(struct vnode *, struct cred *, caller_context_t *);

#endif

#ifdef  __cplusplus
}
#endif
#endif  /* _SYS_DECOMP_H */