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 }; 78 79 static int 80 md_init(void) 81 { 82 83 return (0); 84 } 85 86 static int 87 md_strategy(void *devdata, int rw, daddr_t blk, size_t size, char *buf, 88 size_t *rsize) 89 { 90 struct devdesc *dev = (struct devdesc *)devdata; 91 size_t ofs; 92 93 if (dev->d_unit != 0) 94 return (ENXIO); 95 96 if (blk < 0 || blk >= (MD_IMAGE_SIZE / MD_BLOCK_SIZE)) 97 return (EIO); 98 99 if (size % MD_BLOCK_SIZE) 100 return (EIO); 101 102 ofs = blk * MD_BLOCK_SIZE; 103 if ((ofs + size) > MD_IMAGE_SIZE) 104 size = MD_IMAGE_SIZE - ofs; 105 106 if (rsize != 0) 107 *rsize = size; 108 109 switch (rw & F_MASK) { 110 case F_READ: 111 bcopy(md_image.start + ofs, buf, size); 112 return (0); 113 case F_WRITE: 114 bcopy(buf, md_image.start + ofs, size); 115 return (0); 116 } 117 118 return (ENODEV); 119 } 120 121 static int 122 md_open(struct open_file *f, ...) 123 { 124 va_list ap; 125 struct devdesc *dev; 126 127 va_start(ap, f); 128 dev = va_arg(ap, struct devdesc *); 129 va_end(ap); 130 131 if (dev->d_unit != 0) 132 return (ENXIO); 133 134 return (0); 135 } 136 137 static int 138 md_close(struct open_file *f) 139 { 140 struct devdesc *dev; 141 142 dev = (struct devdesc *)(f->f_devdata); 143 return ((dev->d_unit != 0) ? ENXIO : 0); 144 } 145 146 static int 147 md_print(int verbose) 148 { 149 150 printf("%s devices:", md_dev.dv_name); 151 if (pager_output("\n") != 0) 152 return (1); 153 154 printf("MD (%u bytes)", MD_IMAGE_SIZE); 155 return (pager_output("\n")); 156 } 157