From 066b1a5c7bda073983abfd26c58f78fd353b6e95 Mon Sep 17 00:00:00 2001 From: Marcel Moolenaar Date: Sun, 13 Dec 2009 01:20:32 +0000 Subject: [PATCH] Add support for memory disk (md). The size of the memory disk is determined by MD_IMAGE_SIZE. A file system can be embedded into the loader with /sys/tools/embed_mfs.sh. Note that md.c is not included when MD_IMAGE_SIZE is not set. --- sys/boot/common/Makefile.inc | 5 ++ sys/boot/common/md.c | 151 +++++++++++++++++++++++++++++++++++ 2 files changed, 156 insertions(+) create mode 100644 sys/boot/common/md.c diff --git a/sys/boot/common/Makefile.inc b/sys/boot/common/Makefile.inc index 1f31aa9b601d..bb0d12098601 100644 --- a/sys/boot/common/Makefile.inc +++ b/sys/boot/common/Makefile.inc @@ -23,6 +23,11 @@ SRCS+= dev_net.c SRCS+= bcache.c .endif +.if defined(MD_IMAGE_SIZE) +CFLAGS+= -DMD_IMAGE_SIZE=${MD_IMAGE_SIZE} +SRCS+= md.c +.endif + # Machine-independant ISA PnP .if defined(HAVE_ISABUS) SRCS+= isapnp.c diff --git a/sys/boot/common/md.c b/sys/boot/common/md.c new file mode 100644 index 000000000000..6d2d2b455748 --- /dev/null +++ b/sys/boot/common/md.c @@ -0,0 +1,151 @@ +/*- + * Copyright (c) 2009 Marcel Moolenaar + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +__FBSDID("$FreeBSD$"); + +#include +#include +#include +#include +#include + +#include "bootstrap.h" + +#define MD_BLOCK_SIZE 512 + +#ifndef MD_IMAGE_SIZE +#error Must be compiled with MD_IMAGE_SIZE defined +#endif +#if (MD_IMAGE_SIZE == 0 || MD_IMAGE_SIZE % MD_BLOCK_SIZE) +#error Image size must be a multiple of 512. +#endif + +/* + * Preloaded image gets put here. + * Applications that patch the object with the image can determine + * the size looking at the start and end markers (strings), + * so we want them contiguous. + */ +static struct { + u_char start[MD_IMAGE_SIZE]; + u_char end[128]; +} md_image = { + .start = "MFS Filesystem goes here", + .end = "MFS Filesystem had better STOP here", +}; + +/* devsw I/F */ +static int md_init(void); +static int md_strategy(void *, int, daddr_t, size_t, char *, size_t *); +static int md_open(struct open_file *, ...); +static int md_close(struct open_file *); +static void md_print(int); + +struct devsw md_dev = { + "md", + DEVT_DISK, + md_init, + md_strategy, + md_open, + md_close, + noioctl, + md_print +}; + +static int +md_init(void) +{ + + return (0); +} + +static int +md_strategy(void *devdata, int rw, daddr_t blk, size_t size, char *buf, + size_t *rsize) +{ + struct devdesc *dev = (struct devdesc *)devdata; + size_t ofs; + + if (dev->d_unit != 0) + return (ENXIO); + + if (blk < 0 || blk >= (MD_IMAGE_SIZE / MD_BLOCK_SIZE)) + return (EIO); + + if (size % MD_BLOCK_SIZE) + return (EIO); + + ofs = blk * MD_BLOCK_SIZE; + if ((ofs + size) > MD_IMAGE_SIZE) + size = MD_IMAGE_SIZE - ofs; + + if (rsize != 0) + *rsize = size; + + switch (rw) { + case F_READ: + bcopy(md_image.start + ofs, buf, size); + return (0); + case F_WRITE: + bcopy(buf, md_image.start + ofs, size); + return (0); + } + + return (ENODEV); +} + +static int +md_open(struct open_file *f, ...) +{ + va_list ap; + struct devdesc *dev; + + va_start(ap, f); + dev = va_arg(ap, struct devdesc *); + va_end(ap); + + if (dev->d_unit != 0) + return (ENXIO); + + return (0); +} + +static int +md_close(struct open_file *f) +{ + struct devdesc *dev; + + dev = (struct devdesc *)(f->f_devdata); + return ((dev->d_unit != 0) ? ENXIO : 0); +} + +static void +md_print(int verbose) +{ + + printf("MD (%u bytes)\n", MD_IMAGE_SIZE); +}