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 <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <stand.h> 31 #include <sys/param.h> 32 #include <sys/endian.h> 33 #include <sys/queue.h> 34 #include <machine/stdarg.h> 35 36 #include "bootstrap.h" 37 38 #define MD_BLOCK_SIZE 512 39 40 #ifndef MD_IMAGE_SIZE 41 #error Must be compiled with MD_IMAGE_SIZE defined 42 #endif 43 #if (MD_IMAGE_SIZE == 0 || MD_IMAGE_SIZE % MD_BLOCK_SIZE) 44 #error Image size must be a multiple of 512. 45 #endif 46 47 /* 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. 52 */ 53 static struct { 54 u_char start[MD_IMAGE_SIZE]; 55 u_char end[128]; 56 } md_image = { 57 .start = "MFS Filesystem goes here", 58 .end = "MFS Filesystem had better STOP here", 59 }; 60 61 /* devsw I/F */ 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); 67 68 struct devsw md_dev = { 69 "md", 70 DEVT_DISK, 71 md_init, 72 md_strategy, 73 md_open, 74 md_close, 75 noioctl, 76 md_print, 77 NULL 78 }; 79 80 static int 81 md_init(void) 82 { 83 84 return (0); 85 } 86 87 static int 88 md_strategy(void *devdata, int rw, daddr_t blk, size_t size, 89 char *buf, size_t *rsize) 90 { 91 struct devdesc *dev = (struct devdesc *)devdata; 92 size_t ofs; 93 94 if (dev->d_unit != 0) 95 return (ENXIO); 96 97 if (blk < 0 || blk >= (MD_IMAGE_SIZE / MD_BLOCK_SIZE)) 98 return (EIO); 99 100 if (size % MD_BLOCK_SIZE) 101 return (EIO); 102 103 ofs = blk * MD_BLOCK_SIZE; 104 if ((ofs + size) > MD_IMAGE_SIZE) 105 size = MD_IMAGE_SIZE - ofs; 106 107 if (rsize != NULL) 108 *rsize = size; 109 110 switch (rw & F_MASK) { 111 case F_READ: 112 bcopy(md_image.start + ofs, buf, size); 113 return (0); 114 case F_WRITE: 115 bcopy(buf, md_image.start + ofs, size); 116 return (0); 117 } 118 119 return (ENODEV); 120 } 121 122 static int 123 md_open(struct open_file *f, ...) 124 { 125 va_list ap; 126 struct devdesc *dev; 127 128 va_start(ap, f); 129 dev = va_arg(ap, struct devdesc *); 130 va_end(ap); 131 132 if (dev->d_unit != 0) 133 return (ENXIO); 134 135 return (0); 136 } 137 138 static int 139 md_close(struct open_file *f) 140 { 141 struct devdesc *dev; 142 143 dev = (struct devdesc *)(f->f_devdata); 144 return ((dev->d_unit != 0) ? ENXIO : 0); 145 } 146 147 static int 148 md_print(int verbose) 149 { 150 151 printf("%s devices:", md_dev.dv_name); 152 if (pager_output("\n") != 0) 153 return (1); 154 155 printf("MD (%u bytes)", MD_IMAGE_SIZE); 156 return (pager_output("\n")); 157 } 158