xref: /netbsd-src/sys/dev/fssvar.h (revision 8ac07aec990b9d2e483062509d0a9fa5b4f57cf2)
1 /*	$NetBSD: fssvar.h,v 1.18 2008/01/04 21:33:17 xtraeme Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2007 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Juergen Hannken-Illjes.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #ifndef _SYS_DEV_FSSVAR_H
40 #define _SYS_DEV_FSSVAR_H
41 
42 #include <sys/simplelock.h>
43 
44 #define FSS_UNCONFIG_ON_CLOSE	0x01	/* Unconfigure on last close */
45 
46 struct fss_set {
47 	char		*fss_mount;	/* Mount point of file system */
48 	char		*fss_bstore;	/* Path of backing store */
49 	blksize_t	fss_csize;	/* Preferred cluster size */
50 };
51 
52 struct fss_get {
53 	char		fsg_mount[MNAMELEN]; /* Mount point of file system */
54 	struct timeval	fsg_time;	/* Time this snapshot was taken */
55 	blksize_t	fsg_csize;	/* Current cluster size */
56 	blkcnt_t	fsg_mount_size;	/* # clusters on file system */
57 	blkcnt_t	fsg_bs_size;	/* # clusters on backing store */
58 };
59 
60 #define FSSIOCSET	_IOW('F', 0, struct fss_set)	/* Configure */
61 #define FSSIOCGET	_IOR('F', 1, struct fss_get)	/* Status */
62 #define FSSIOCCLR	_IO('F', 2)			/* Unconfigure */
63 #define FSSIOFSET	_IOW('F', 3, int)		/* Set flags */
64 #define FSSIOFGET	_IOR('F', 4, int)		/* Get flags */
65 
66 #ifdef _KERNEL
67 
68 #include <sys/bufq.h>
69 
70 #define FSS_CLUSTER_MAX	(1<<24)		/* Upper bound of clusters. The
71 					   sc_copied map uses up to
72 					   FSS_CLUSTER_MAX/NBBY bytes */
73 
74 #define FSS_LOCK(sc, s) \
75 	do { \
76 		(s) = splbio(); \
77 		simple_lock(&(sc)->sc_slock); \
78 	} while (/*CONSTCOND*/0)
79 
80 #define FSS_UNLOCK(sc, s) \
81 	do { \
82 		simple_unlock(&(sc)->sc_slock); \
83 		splx((s)); \
84 	} while (/*CONSTCOND*/0)
85 
86 /* Device to softc, NULL on error */
87 #define FSS_DEV_TO_SOFTC(dev) \
88 	(minor((dev)) < 0 || minor((dev)) >= NFSS ? NULL : \
89 	    &fss_softc[minor((dev))])
90 
91 /* Check if still valid */
92 #define FSS_ISVALID(sc) \
93 	(((sc)->sc_flags & (FSS_ACTIVE|FSS_ERROR)) == FSS_ACTIVE)
94 
95 /* Offset to cluster */
96 #define FSS_BTOCL(sc, off) \
97 	((off) >> (sc)->sc_clshift)
98 
99 /* Cluster to offset */
100 #define FSS_CLTOB(sc, cl) \
101 	((off_t)(cl) << (sc)->sc_clshift)
102 
103 /* Offset from start of cluster */
104 #define FSS_CLOFF(sc, off) \
105 	((off) & (sc)->sc_clmask)
106 
107 /* Size of cluster */
108 #define FSS_CLSIZE(sc) \
109 	(1 << (sc)->sc_clshift)
110 
111 /* Offset to backing store block */
112 #define FSS_BTOFSB(sc, off) \
113 	((off) >> (sc)->sc_bs_bshift)
114 
115 /* Backing store block to offset */
116 #define FSS_FSBTOB(sc, blk) \
117 	((off_t)(blk) << (sc)->sc_bs_bshift)
118 
119 /* Offset from start of backing store block */
120 #define FSS_FSBOFF(sc, off) \
121 	((off) & (sc)->sc_bs_bmask)
122 
123 /* Size of backing store block */
124 #define FSS_FSBSIZE(sc) \
125 	(1 << (sc)->sc_bs_bshift)
126 
127 typedef enum {
128 	FSS_READ,
129 	FSS_WRITE
130 } fss_io_type;
131 
132 typedef enum {
133 	FSS_CACHE_FREE	= 0,		/* Cache entry is free */
134 	FSS_CACHE_BUSY	= 1,		/* Cache entry is read from device */
135 	FSS_CACHE_VALID	= 2		/* Cache entry contains valid data */
136 } fss_cache_type;
137 
138 struct fss_cache {
139 	fss_cache_type	fc_type;	/* Current state */
140 	struct fss_softc *fc_softc;	/* Backlink to our softc */
141 	volatile int	fc_xfercount;	/* Number of outstanding transfers */
142 	u_int32_t	fc_cluster;	/* Cluster number of this entry */
143 	void *		fc_data;	/* Data */
144 };
145 
146 struct fss_softc {
147 	int		sc_unit;	/* Logical unit number */
148 	struct simplelock sc_slock;	/* Protect this softc */
149 	kmutex_t	sc_lock;	/* Sleep lock for fss_ioctl */
150 	volatile int	sc_flags;	/* Flags */
151 #define FSS_ACTIVE	0x01		/* Snapshot is active */
152 #define FSS_ERROR	0x02		/* I/O error occurred */
153 #define FSS_BS_THREAD	0x04		/* Kernel thread is running */
154 #define FSS_PERSISTENT	0x20		/* File system internal snapshot */
155 #define FSS_CDEV_OPEN	0x40		/* character device open */
156 #define FSS_BDEV_OPEN	0x80		/* block device open */
157 	int		sc_uflags;	/* User visible flags */
158 	struct mount	*sc_mount;	/* Mount point */
159 	char		sc_mntname[MNAMELEN]; /* Mount point */
160 	struct timeval	sc_time;	/* Time this snapshot was taken */
161 	dev_t		sc_bdev;	/* Underlying block device */
162 	struct vnode	*sc_bs_vp;	/* Our backing store */
163 	off_t		sc_bs_size;	/* Its size in bytes */
164 	int		sc_bs_bshift;	/* Shift of backing store block */
165 	u_int32_t	sc_bs_bmask;	/* Mask of backing store block */
166 	struct lwp	*sc_bs_lwp;	/* Our kernel thread */
167 	int		sc_clshift;	/* Shift of cluster size */
168 	u_int32_t	sc_clmask;	/* Mask of cluster size */
169 	u_int32_t	sc_clcount;	/* # clusters in file system */
170 	u_int8_t	*sc_copied;	/* Map of clusters already copied */
171 	long		sc_clresid;	/* Bytes in last cluster */
172 	int		sc_cache_size;	/* Number of entries in sc_cache */
173 	struct fss_cache *sc_cache;	/* Cluster cache */
174 	struct bufq_state *sc_bufq;	/* Transfer queue */
175 	u_int32_t	sc_clnext;	/* Next free cluster on backing store */
176 	int		sc_indir_size;	/* # clusters for indirect mapping */
177 	u_int8_t	*sc_indir_valid; /* Map of valid indirect clusters */
178 	u_int32_t	sc_indir_cur;	/* Current indir cluster number */
179 	int		sc_indir_dirty;	/* Current indir cluster modified */
180 	u_int32_t	*sc_indir_data;	/* Current indir cluster data */
181 };
182 
183 int fss_umount_hook(struct mount *, int);
184 
185 #endif /* _KERNEL */
186 
187 #endif /* !_SYS_DEV_FSSVAR_H */
188