2 * Copyright (c) 2009 Marcel Moolenaar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
31 #include <sys/param.h>
32 #include <sys/endian.h>
33 #include <sys/queue.h>
34 #include <machine/stdarg.h>
36 #include "bootstrap.h"
38 #define MD_BLOCK_SIZE 512
41 #error Must be compiled with MD_IMAGE_SIZE defined
43 #if (MD_IMAGE_SIZE == 0 || MD_IMAGE_SIZE % MD_BLOCK_SIZE)
44 #error Image size must be a multiple of 512.
48 * Preloaded image gets put here.
49 * Applications that patch the object with the image can determine
50 * the size looking at the start and end markers (strings),
51 * so we want them contiguous.
54 u_char start[MD_IMAGE_SIZE];
57 .start = "MFS Filesystem goes here",
58 .end = "MFS Filesystem had better STOP here",
62 static int md_init(void);
63 static int md_strategy(void *, int, daddr_t, size_t, char *, size_t *);
64 static int md_open(struct open_file *, ...);
65 static int md_close(struct open_file *);
66 static int md_print(int);
68 struct devsw md_dev = {
88 md_strategy(void *devdata, int rw, daddr_t blk, size_t size,
89 char *buf, size_t *rsize)
91 struct devdesc *dev = (struct devdesc *)devdata;
97 if (blk < 0 || blk >= (MD_IMAGE_SIZE / MD_BLOCK_SIZE))
100 if (size % MD_BLOCK_SIZE)
103 ofs = blk * MD_BLOCK_SIZE;
104 if ((ofs + size) > MD_IMAGE_SIZE)
105 size = MD_IMAGE_SIZE - ofs;
110 switch (rw & F_MASK) {
112 bcopy(md_image.start + ofs, buf, size);
115 bcopy(buf, md_image.start + ofs, size);
123 md_open(struct open_file *f, ...)
129 dev = va_arg(ap, struct devdesc *);
132 if (dev->d_unit != 0)
139 md_close(struct open_file *f)
143 dev = (struct devdesc *)(f->f_devdata);
144 return ((dev->d_unit != 0) ? ENXIO : 0);
148 md_print(int verbose)
151 printf("%s devices:", md_dev.dv_name);
152 if (pager_output("\n") != 0)
155 printf("MD (%u bytes)", MD_IMAGE_SIZE);
156 return (pager_output("\n"));