xref: /illumos-gate/usr/src/uts/common/sys/fs/decomp.h (revision 1d7f3fad)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_SYS_DECOMP_H
27 #define	_SYS_DECOMP_H
28 
29 #ifdef	__cplusplus
30 extern "C" {
31 #endif
32 
33 #define	CH_MAGIC_ZLIB	0x5a636d70	/* ZLIB compression */
34 #define	CH_MAGIC_GZIP	0x8B1F		/* GZIP compression */
35 
36 #define	CH_VERSION	1
37 
38 #define	CH_ALG_ZLIB	1
39 
40 struct comphdr {
41 	uint64_t	ch_magic;
42 	uint64_t	ch_version;
43 	uint64_t	ch_algorithm;
44 	uint64_t	ch_fsize;
45 	uint64_t	ch_blksize;
46 	uint64_t	ch_blkmap[1];
47 };
48 
49 #define	ZMAXBUF(n)	((n) + ((n) / 1000) + 12)
50 
51 #ifdef	_KERNEL
52 
53 struct dcnode {
54 	struct vnode	*dc_vp;
55 	struct vnode	*dc_subvp;
56 	struct kmem_cache *dc_bufcache;
57 	kmutex_t	dc_lock;
58 	struct dcnode	*dc_hash;
59 	struct dcnode	*dc_lrunext;
60 	struct dcnode	*dc_lruprev;
61 	struct comphdr	*dc_hdr;
62 	size_t		dc_hdrsize;
63 	size_t		dc_zmax;
64 	int		dc_mapcnt;
65 };
66 
67 #define	VTODC(vp)	((struct dcnode *)(vp)->v_data)
68 #define	DCTOV(dp)	((dp)->dc_vp)
69 
70 struct vnode	*decompvp(struct vnode *, struct cred *, caller_context_t *);
71 
72 #endif
73 
74 #ifdef	__cplusplus
75 }
76 #endif
77 #endif	/* _SYS_DECOMP_H */
78