sys/dev/fssvar.h

   1 /*      $NetBSD: fssvar.h,v 1.22 2008/09/14 16:10:19 hannken 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 /* Check if still valid */
  68 #define FSS_ISVALID(sc) \
  69         (((sc)->sc_flags & (FSS_ACTIVE|FSS_ERROR)) == FSS_ACTIVE)
  70
  71 /* Offset to cluster */
  72 #define FSS_BTOCL(sc, off) \
  73         ((off) >> (sc)->sc_clshift)
  74
  75 /* Cluster to offset */
  76 #define FSS_CLTOB(sc, cl) \
  77         ((off_t)(cl) << (sc)->sc_clshift)
  78
  79 /* Offset from start of cluster */
  80 #define FSS_CLOFF(sc, off) \
  81         ((off) & (sc)->sc_clmask)
  82
  83 /* Size of cluster */
  84 #define FSS_CLSIZE(sc) \
  85         (1 << (sc)->sc_clshift)
  86
  87 /* Offset to backing store block */
  88 #define FSS_BTOFSB(sc, off) \
  89         ((off) >> (sc)->sc_bs_bshift)
  90
  91 /* Backing store block to offset */
  92 #define FSS_FSBTOB(sc, blk) \
  93         ((off_t)(blk) << (sc)->sc_bs_bshift)
  94
  95 /* Offset from start of backing store block */
  96 #define FSS_FSBOFF(sc, off) \
  97         ((off) & (sc)->sc_bs_bmask)
  98
  99 /* Size of backing store block */
 100 #define FSS_FSBSIZE(sc) \
 101         (1 << (sc)->sc_bs_bshift)
 102
 103 typedef enum {
 104         FSS_READ,
 105         FSS_WRITE
 106 } fss_io_type;
 107
 108 typedef enum {
 109         FSS_CACHE_FREE  = 0,            /* Cache entry is free */
 110         FSS_CACHE_BUSY  = 1,            /* Cache entry is read from device */
 111         FSS_CACHE_VALID = 2             /* Cache entry contains valid data */
 112 } fss_cache_type;
 113
 114 struct fss_cache {
 115         fss_cache_type  fc_type;        /* Current state */
 116         u_int32_t       fc_cluster;     /* Cluster number of this entry */
 117         kcondvar_t      fc_state_cv;    /* Signals state change from busy */
 118         void *          fc_data;        /* Data */
 119 };
 120
 121 struct fss_softc {
 122         device_t        sc_dev;         /* Self */
 123         kmutex_t        sc_slock;       /* Protect this softc */
 124         kmutex_t        sc_lock;        /* Sleep lock for fss_ioctl */
 125         kcondvar_t      sc_work_cv;     /* Signals work for the kernel thread */
 126         kcondvar_t      sc_cache_cv;    /* Signals free cache slot */
 127         volatile int    sc_flags;       /* Flags */
 128 #define FSS_ACTIVE      0x01            /* Snapshot is active */
 129 #define FSS_ERROR       0x02            /* I/O error occurred */
 130 #define FSS_BS_THREAD   0x04            /* Kernel thread is running */
 131 #define FSS_PERSISTENT  0x20            /* File system internal snapshot */
 132 #define FSS_CDEV_OPEN   0x40            /* character device open */
 133 #define FSS_BDEV_OPEN   0x80            /* block device open */
 134         int             sc_uflags;      /* User visible flags */
 135         struct disk     *sc_dkdev;      /* Generic disk device info */
 136         struct mount    *sc_mount;      /* Mount point */
 137         char            sc_mntname[MNAMELEN]; /* Mount point */
 138         struct timeval  sc_time;        /* Time this snapshot was taken */
 139         dev_t           sc_bdev;        /* Underlying block device */
 140         struct vnode    *sc_bs_vp;      /* Our backing store */
 141         off_t           sc_bs_size;     /* Its size in bytes */
 142         int             sc_bs_bshift;   /* Shift of backing store block */
 143         u_int32_t       sc_bs_bmask;    /* Mask of backing store block */
 144         struct lwp      *sc_bs_lwp;     /* Our kernel thread */
 145         int             sc_clshift;     /* Shift of cluster size */
 146         u_int32_t       sc_clmask;      /* Mask of cluster size */
 147         u_int32_t       sc_clcount;     /* # clusters in file system */
 148         u_int8_t        *sc_copied;     /* Map of clusters already copied */
 149         long            sc_clresid;     /* Bytes in last cluster */
 150         int             sc_cache_size;  /* Number of entries in sc_cache */
 151         struct fss_cache *sc_cache;     /* Cluster cache */
 152         struct bufq_state *sc_bufq;     /* Transfer queue */
 153         u_int32_t       sc_clnext;      /* Next free cluster on backing store */
 154         int             sc_indir_size;  /* # clusters for indirect mapping */
 155         u_int8_t        *sc_indir_valid; /* Map of valid indirect clusters */
 156         u_int32_t       sc_indir_cur;   /* Current indir cluster number */
 157         int             sc_indir_dirty; /* Current indir cluster modified */
 158         u_int32_t       *sc_indir_data; /* Current indir cluster data */
 159 };
 160
 161 #endif /* _KERNEL */
 162
 163 #endif /* !_SYS_DEV_FSSVAR_H */