1 /*-
2 * Copyright (c) 2009 Marcel Moolenaar
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27 #include <stand.h>
28 #include <sys/param.h>
29 #include <sys/endian.h>
30 #include <sys/queue.h>
31 #include <sys/stdarg.h>
32
33 #include "bootstrap.h"
34
35 #define MD_BLOCK_SIZE 512
36
37 #ifndef MD_IMAGE_SIZE
38 #error Must be compiled with MD_IMAGE_SIZE defined
39 #endif
40 #if (MD_IMAGE_SIZE == 0 || MD_IMAGE_SIZE % MD_BLOCK_SIZE)
41 #error Image size must be a multiple of 512.
42 #endif
43
44 /*
45 * Preloaded image gets put here.
46 * Applications that patch the object with the image can determine
47 * the size looking at the start and end markers (strings),
48 * so we want them contiguous.
49 */
50 static struct {
51 u_char start[MD_IMAGE_SIZE];
52 u_char end[128];
53 } md_image = {
54 .start = "MFS Filesystem goes here",
55 .end = "MFS Filesystem had better STOP here",
56 };
57
58 /* devsw I/F */
59 static int md_init(void);
60 static int md_strategy(void *, int, daddr_t, size_t, char *, size_t *);
61 static int md_open(struct open_file *, ...);
62 static int md_close(struct open_file *);
63 static int md_print(int);
64
65 struct devsw md_dev = {
66 .dv_name = "md",
67 .dv_type = DEVT_DISK,
68 .dv_init = md_init,
69 .dv_strategy = md_strategy,
70 .dv_open = md_open,
71 .dv_close = md_close,
72 .dv_ioctl = noioctl,
73 .dv_print = md_print,
74 .dv_cleanup = nullsys,
75 };
76
77 static int
md_init(void)78 md_init(void)
79 {
80
81 return (0);
82 }
83
84 static int
md_strategy(void * devdata,int rw,daddr_t blk,size_t size,char * buf,size_t * rsize)85 md_strategy(void *devdata, int rw, daddr_t blk, size_t size,
86 char *buf, size_t *rsize)
87 {
88 struct devdesc *dev = (struct devdesc *)devdata;
89 size_t ofs;
90
91 if (dev->d_unit != 0)
92 return (ENXIO);
93
94 if (blk < 0 || blk >= (MD_IMAGE_SIZE / MD_BLOCK_SIZE))
95 return (EIO);
96
97 if (size % MD_BLOCK_SIZE)
98 return (EIO);
99
100 ofs = blk * MD_BLOCK_SIZE;
101 if ((ofs + size) > MD_IMAGE_SIZE)
102 size = MD_IMAGE_SIZE - ofs;
103
104 if (rsize != NULL)
105 *rsize = size;
106
107 switch (rw & F_MASK) {
108 case F_READ:
109 bcopy(md_image.start + ofs, buf, size);
110 return (0);
111 case F_WRITE:
112 bcopy(buf, md_image.start + ofs, size);
113 return (0);
114 }
115
116 return (ENODEV);
117 }
118
119 static int
md_open(struct open_file * f,...)120 md_open(struct open_file *f, ...)
121 {
122 va_list ap;
123 struct devdesc *dev;
124
125 va_start(ap, f);
126 dev = va_arg(ap, struct devdesc *);
127 va_end(ap);
128
129 if (dev->d_unit != 0)
130 return (ENXIO);
131
132 return (0);
133 }
134
135 static int
md_close(struct open_file * f)136 md_close(struct open_file *f)
137 {
138 struct devdesc *dev;
139
140 dev = (struct devdesc *)(f->f_devdata);
141 return ((dev->d_unit != 0) ? ENXIO : 0);
142 }
143
144 static int
md_print(int verbose)145 md_print(int verbose)
146 {
147
148 printf("%s devices:", md_dev.dv_name);
149 if (pager_output("\n") != 0)
150 return (1);
151
152 printf("MD (%u bytes)", MD_IMAGE_SIZE);
153 return (pager_output("\n"));
154 }
155