1 /*
2 * Copyright (c) 2007 The DragonFly Project. All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 /*
36 * Virtual CDROM driver
37 */
38 #include <sys/types.h>
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/kernel.h>
42 #include <sys/malloc.h>
43 #include <sys/conf.h>
44 #include <sys/buf.h>
45 #include <sys/devicestat.h>
46 #include <sys/disk.h>
47 #include <machine/md_var.h>
48
49 #include <sys/buf2.h>
50
51 #include <sys/stat.h>
52 #include <unistd.h>
53
54 struct vcd_softc {
55 struct bio_queue_head bio_queue;
56 struct devstat stats;
57 struct disk disk;
58 cdev_t dev;
59 int unit;
60 int fd;
61 };
62
63 static d_strategy_t vcdstrategy;
64 static d_open_t vcdopen;
65
66 static struct dev_ops vcd_ops = {
67 { "vcd", 0, D_DISK },
68 .d_open = vcdopen,
69 .d_close = nullclose,
70 .d_read = physread,
71 .d_write = physwrite,
72 .d_strategy = vcdstrategy,
73 };
74
75 static void
vcdinit(void * dummy __unused)76 vcdinit(void *dummy __unused)
77 {
78 struct vkdisk_info *dsk;
79 struct vcd_softc *sc;
80 struct disk_info info;
81 struct stat st;
82 int i;
83
84 for (i = 0; i < DiskNum; i++) {
85 /* check that the 'bus device' has been initialized */
86 dsk = &DiskInfo[i];
87 if (dsk == NULL || dsk->type != VKD_CD)
88 continue;
89 if (dsk->fd < 0 || fstat(dsk->fd, &st) < 0)
90 continue;
91
92 /* and create a new device */
93 sc = kmalloc(sizeof(*sc), M_DEVBUF, M_WAITOK | M_ZERO);
94 sc->unit = dsk->unit;
95 sc->fd = dsk->fd;
96 bioq_init(&sc->bio_queue);
97 devstat_add_entry(&sc->stats, "vcd", sc->unit, 2048,
98 DEVSTAT_NO_ORDERED_TAGS,
99 DEVSTAT_TYPE_DIRECT | DEVSTAT_TYPE_IF_OTHER,
100 DEVSTAT_PRIORITY_DISK);
101 sc->dev = disk_create(sc->unit, &sc->disk, &vcd_ops);
102 sc->dev->si_drv1 = sc;
103 sc->dev->si_iosize_max = 256 * 1024;
104
105 bzero(&info, sizeof(info));
106 info.d_media_blksize = 2048;
107 info.d_media_blocks = st.st_size / info.d_media_blksize;
108 info.d_dsflags = DSO_ONESLICE | DSO_COMPATLABEL | DSO_COMPATPARTA |
109 DSO_RAWEXTENSIONS;
110 info.d_nheads = 1;
111 info.d_ncylinders = 1;
112 info.d_secpertrack = info.d_media_blocks;
113 info.d_secpercyl = info.d_secpertrack * info.d_nheads;
114
115 disk_setdiskinfo(&sc->disk, &info);
116 }
117 }
118
119 SYSINIT(vcdisk, SI_SUB_DRIVERS, SI_ORDER_FIRST, vcdinit, NULL);
120
121 static int
vcdopen(struct dev_open_args * ap)122 vcdopen(struct dev_open_args *ap)
123 {
124 struct vcd_softc *sc;
125 struct stat st;
126 cdev_t dev;
127
128 dev = ap->a_head.a_dev;
129 sc = dev->si_drv1;
130 if (fstat(sc->fd, &st) < 0 || st.st_size == 0)
131 return(ENXIO);
132
133 return(0);
134 }
135
136 static int
vcdstrategy(struct dev_strategy_args * ap)137 vcdstrategy(struct dev_strategy_args *ap)
138 {
139 struct bio *bio = ap->a_bio;
140 struct buf *bp;
141 struct vcd_softc *sc;
142 cdev_t dev;
143 int n;
144
145 dev = ap->a_head.a_dev;
146 sc = dev->si_drv1;
147
148 bioqdisksort(&sc->bio_queue, bio);
149 while ((bio = bioq_takefirst(&sc->bio_queue)) != NULL) {
150 bp = bio->bio_buf;
151
152 devstat_start_transaction(&sc->stats);
153
154 switch(bp->b_cmd) {
155 case BUF_CMD_READ:
156 n = pread(sc->fd, bp->b_data,
157 bp->b_bcount, bio->bio_offset);
158 break;
159 case BUF_CMD_WRITE:
160 /* XXX HANDLE SHORT WRITE XXX */
161 n = pwrite(sc->fd, bp->b_data,
162 bp->b_bcount, bio->bio_offset);
163 break;
164 default:
165 panic("vcd: bad b_cmd %d", bp->b_cmd);
166 break; /* not reached */
167 }
168 if (n != bp->b_bcount) {
169 bp->b_error = EIO;
170 bp->b_flags |= B_ERROR;
171 }
172
173 bp->b_resid = bp->b_bcount - n;
174 devstat_end_transaction_buf(&sc->stats, bp);
175 biodone(bio);
176 }
177 return(0);
178 }
179