xref: /netbsd-src/sys/dev/fssvar.h (revision 2980e352a13e8f0b545a366830c411e7a542ada8)
1 /*	$NetBSD: fssvar.h,v 1.19 2008/04/28 20:23:46 martin 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #ifndef _SYS_DEV_FSSVAR_H
33 #define _SYS_DEV_FSSVAR_H
34 
35 #include <sys/simplelock.h>
36 
37 #define FSS_UNCONFIG_ON_CLOSE	0x01	/* Unconfigure on last close */
38 
39 struct fss_set {
40 	char		*fss_mount;	/* Mount point of file system */
41 	char		*fss_bstore;	/* Path of backing store */
42 	blksize_t	fss_csize;	/* Preferred cluster size */
43 };
44 
45 struct fss_get {
46 	char		fsg_mount[MNAMELEN]; /* Mount point of file system */
47 	struct timeval	fsg_time;	/* Time this snapshot was taken */
48 	blksize_t	fsg_csize;	/* Current cluster size */
49 	blkcnt_t	fsg_mount_size;	/* # clusters on file system */
50 	blkcnt_t	fsg_bs_size;	/* # clusters on backing store */
51 };
52 
53 #define FSSIOCSET	_IOW('F', 0, struct fss_set)	/* Configure */
54 #define FSSIOCGET	_IOR('F', 1, struct fss_get)	/* Status */
55 #define FSSIOCCLR	_IO('F', 2)			/* Unconfigure */
56 #define FSSIOFSET	_IOW('F', 3, int)		/* Set flags */
57 #define FSSIOFGET	_IOR('F', 4, int)		/* Get flags */
58 
59 #ifdef _KERNEL
60 
61 #include <sys/bufq.h>
62 
63 #define FSS_CLUSTER_MAX	(1<<24)		/* Upper bound of clusters. The
64 					   sc_copied map uses up to
65 					   FSS_CLUSTER_MAX/NBBY bytes */
66 
67 #define FSS_LOCK(sc, s) \
68 	do { \
69 		(s) = splbio(); \
70 		simple_lock(&(sc)->sc_slock); \
71 	} while (/*CONSTCOND*/0)
72 
73 #define FSS_UNLOCK(sc, s) \
74 	do { \
75 		simple_unlock(&(sc)->sc_slock); \
76 		splx((s)); \
77 	} while (/*CONSTCOND*/0)
78 
79 /* Device to softc, NULL on error */
80 #define FSS_DEV_TO_SOFTC(dev) \
81 	(minor((dev)) < 0 || minor((dev)) >= NFSS ? NULL : \
82 	    &fss_softc[minor((dev))])
83 
84 /* Check if still valid */
85 #define FSS_ISVALID(sc) \
86 	(((sc)->sc_flags & (FSS_ACTIVE|FSS_ERROR)) == FSS_ACTIVE)
87 
88 /* Offset to cluster */
89 #define FSS_BTOCL(sc, off) \
90 	((off) >> (sc)->sc_clshift)
91 
92 /* Cluster to offset */
93 #define FSS_CLTOB(sc, cl) \
94 	((off_t)(cl) << (sc)->sc_clshift)
95 
96 /* Offset from start of cluster */
97 #define FSS_CLOFF(sc, off) \
98 	((off) & (sc)->sc_clmask)
99 
100 /* Size of cluster */
101 #define FSS_CLSIZE(sc) \
102 	(1 << (sc)->sc_clshift)
103 
104 /* Offset to backing store block */
105 #define FSS_BTOFSB(sc, off) \
106 	((off) >> (sc)->sc_bs_bshift)
107 
108 /* Backing store block to offset */
109 #define FSS_FSBTOB(sc, blk) \
110 	((off_t)(blk) << (sc)->sc_bs_bshift)
111 
112 /* Offset from start of backing store block */
113 #define FSS_FSBOFF(sc, off) \
114 	((off) & (sc)->sc_bs_bmask)
115 
116 /* Size of backing store block */
117 #define FSS_FSBSIZE(sc) \
118 	(1 << (sc)->sc_bs_bshift)
119 
120 typedef enum {
121 	FSS_READ,
122 	FSS_WRITE
123 } fss_io_type;
124 
125 typedef enum {
126 	FSS_CACHE_FREE	= 0,		/* Cache entry is free */
127 	FSS_CACHE_BUSY	= 1,		/* Cache entry is read from device */
128 	FSS_CACHE_VALID	= 2		/* Cache entry contains valid data */
129 } fss_cache_type;
130 
131 struct fss_cache {
132 	fss_cache_type	fc_type;	/* Current state */
133 	struct fss_softc *fc_softc;	/* Backlink to our softc */
134 	volatile int	fc_xfercount;	/* Number of outstanding transfers */
135 	u_int32_t	fc_cluster;	/* Cluster number of this entry */
136 	void *		fc_data;	/* Data */
137 };
138 
139 struct fss_softc {
140 	int		sc_unit;	/* Logical unit number */
141 	struct simplelock sc_slock;	/* Protect this softc */
142 	kmutex_t	sc_lock;	/* Sleep lock for fss_ioctl */
143 	volatile int	sc_flags;	/* Flags */
144 #define FSS_ACTIVE	0x01		/* Snapshot is active */
145 #define FSS_ERROR	0x02		/* I/O error occurred */
146 #define FSS_BS_THREAD	0x04		/* Kernel thread is running */
147 #define FSS_PERSISTENT	0x20		/* File system internal snapshot */
148 #define FSS_CDEV_OPEN	0x40		/* character device open */
149 #define FSS_BDEV_OPEN	0x80		/* block device open */
150 	int		sc_uflags;	/* User visible flags */
151 	struct mount	*sc_mount;	/* Mount point */
152 	char		sc_mntname[MNAMELEN]; /* Mount point */
153 	struct timeval	sc_time;	/* Time this snapshot was taken */
154 	dev_t		sc_bdev;	/* Underlying block device */
155 	struct vnode	*sc_bs_vp;	/* Our backing store */
156 	off_t		sc_bs_size;	/* Its size in bytes */
157 	int		sc_bs_bshift;	/* Shift of backing store block */
158 	u_int32_t	sc_bs_bmask;	/* Mask of backing store block */
159 	struct lwp	*sc_bs_lwp;	/* Our kernel thread */
160 	int		sc_clshift;	/* Shift of cluster size */
161 	u_int32_t	sc_clmask;	/* Mask of cluster size */
162 	u_int32_t	sc_clcount;	/* # clusters in file system */
163 	u_int8_t	*sc_copied;	/* Map of clusters already copied */
164 	long		sc_clresid;	/* Bytes in last cluster */
165 	int		sc_cache_size;	/* Number of entries in sc_cache */
166 	struct fss_cache *sc_cache;	/* Cluster cache */
167 	struct bufq_state *sc_bufq;	/* Transfer queue */
168 	u_int32_t	sc_clnext;	/* Next free cluster on backing store */
169 	int		sc_indir_size;	/* # clusters for indirect mapping */
170 	u_int8_t	*sc_indir_valid; /* Map of valid indirect clusters */
171 	u_int32_t	sc_indir_cur;	/* Current indir cluster number */
172 	int		sc_indir_dirty;	/* Current indir cluster modified */
173 	u_int32_t	*sc_indir_data;	/* Current indir cluster data */
174 };
175 
176 int fss_umount_hook(struct mount *, int);
177 
178 #endif /* _KERNEL */
179 
180 #endif /* !_SYS_DEV_FSSVAR_H */
181