#include <linux/config.h>
#include <linux/sched.h>
#include <linux/minix_fs.h>
#include <linux/ext2_fs.h>
#include <linux/romfs_fs.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/malloc.h>
#include <linux/ioctl.h>
#include <linux/fd.h>
#include <linux/module.h>
#include <linux/init.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/byteorder.h>
extern void wait_for_keypress(void);
#define JMT_RD
/*
* 35 has been officially registered as the RAMDISK major number, but
* so is the original MAJOR number of 1. We're using 1 in
* include/linux/major.h for now
*/
#define MAJOR_NR RAMDISK_MAJOR
#include <linux/blk.h>
/* The RAM disk size is now a parameter */
#define NUM_RAMDISKS 1 /* (16) This cannot be overridden (yet) */
#ifndef MODULE
/* We don't have to load RAM disks or gunzip them in a module. */
#define RD_LOADER
#define BUILD_CRAMDISK
void rd_load(void);
static int crd_load(struct file *fp, struct file *outfp);
#ifdef CONFIG_BLK_DEV_INITRD
static int initrd_users = 0;
#endif
#endif
/* Various static variables go here. Most are used only in the RAM disk code.
*/
static int rd_length[NUM_RAMDISKS];
static int rd_blocksizes[NUM_RAMDISKS];
/*
* Parameters for the boot-loading of the RAM disk. These are set by
* init/main.c (from arguments to the kernel command line) or from the
* architecture-specific setup routine (from the stored boot sector
* information).
*/
int rd_size = 4567; /*4872;*/ /*4096;*/ /* Size of the RAM disks */
#ifndef MODULE
int rd_doload = 0; /* "1" = load RAM disk, 0 = don't load */
int rd_prompt = 1; /* 1 = prompt for RAM disk, 0 = don't prompt */
int rd_image_start = 0; /* starting block # of image */
#ifdef CONFIG_BLK_DEV_INITRD
unsigned long initrd_start,initrd_end;
int mount_initrd = 1; /* zero if initrd should not be mounted */
int initrd_below_start_ok = 0;
#endif
#endif
/*
* Basically, my strategy here is to set up a buffer-head which can't be
* deleted, and make that my Ramdisk. If the request is outside of the
* allocated size, we must get rid of it...
*
*/
static void rd_request(void)
{
unsigned int minor;
int offset, len;
loff_t pos;
#if 0
printk("[.]in rd_request\n");
#endif
repeat:
INIT_REQUEST;
minor = MINOR(CURRENT->rq_dev);
if (minor >= NUM_RAMDISKS) {
end_request(0);
goto repeat;
}
offset = CURRENT->sector << 9;
pos=offset;
len = CURRENT->current_nr_sectors << 9;
if ((offset + len) > rd_length[minor]) {
end_request(0);
goto repeat;
}
/*
* If we're reading, fill the buffer with 0's. This is okay since
* we're using protected buffers which should never get freed...
*
* If we're writing, we protect the buffer.
*/
if (CURRENT->cmd == READ)
{
memset(CURRENT->buffer, 0, len);
#ifdef JMT_RD
initrd_read(NULL,CURRENT->buffer,len,&pos);
#endif
}
else
set_bit(BH_Protected, &CURRENT->bh->b_state);
end_request(1);
goto repeat;
}
static int rd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
int err;
printk("[.]in rd_ioctl\n");
if (!inode || !inode->i_rdev)
return -EINVAL;
switch (cmd) {
case BLKFLSBUF:
if (!capable(CAP_SYS_ADMIN)) return -EACCES;
invalidate_buffers(inode->i_rdev);
break;
case BLKGETSIZE: /* Return device size */
if (!arg) return -EINVAL;
#ifndef JMT_RD
err = verify_area(VERIFY_WRITE, (long *) arg,
sizeof(long));
if (err)
return err;
#endif
put_user(rd_length[MINOR(inode->i_rdev)] / 512,
(long *) arg);
return 0;
default:
break;
};
return 0;
}
#ifdef CONFIG_BLK_DEV_INITRD
static ssize_t initrd_read(struct file *file, char *buf,
size_t count, loff_t *ppos)
{
int left;
left = initrd_end - initrd_start - *ppos;
if (count > left) count = left;
if (count == 0) return 0;
copy_to_user(buf, (char *)initrd_start + *ppos, count);
*ppos += count;
#if 0
printk("[?]initrd_read(~,%d,%d)\n",count,*ppos);
#endif
return count;
}
static int initrd_release(struct inode *inode,struct file *file)
{
unsigned long i;
if (--initrd_users) return 0;
#ifdef JMT_RD
return 0;
#endif
for (i = initrd_start; i < initrd_end; i += PAGE_SIZE)
free_page(i);
initrd_start = 0;
return 0;
}
static struct file_operations initrd_fops = {
NULL, /* lseek */
initrd_read, /* read */
NULL, /* write */
NULL, /* readdir */
NULL, /* poll */
NULL, /* ioctl */
NULL, /* mmap */
NULL, /* open */
NULL, /* flush */
initrd_release, /* release */
NULL /* fsync */
};
#endif
#ifdef JMT_RD
static int jmtrd_open(struct inode * inode, struct file * filp)
{
printk("[*]jmtrd_open(%s)\n",kdevname(inode->i_rdev));
if (DEVICE_NR(inode->i_rdev) >= NUM_RAMDISKS)
return -ENXIO;
MOD_INC_USE_COUNT;
return 0;
}
static int jmtrd_release(struct inode * inode, struct file * filp)
{
MOD_DEC_USE_COUNT;
return 0;
}
static struct file_operations jmtrd_fops = {
NULL, /* lseek - default */
initrd_read, /* read - initrd dev read */
NULL, /*block_write, write - block dev write */
NULL, /* readdir - not here! */
NULL, /* poll */
rd_ioctl, /* ioctl */
NULL, /* mmap */
jmtrd_open, /* open */
NULL, /* flush */
jmtrd_release, /* module needs to decrement use count */
block_fsync /* fsync */
};
#endif
static int rd_open(struct inode * inode, struct file * filp)
{
#ifdef JMT_RD
printk("[*]jmtrd_open(%s)\n",kdevname(inode->i_rdev));
if (MAJOR(inode->i_rdev)==RAMDISK_MAJOR && MINOR(inode->i_rdev)==0)
{
if (!initrd_start) return -ENODEV;
MOD_INC_USE_COUNT;
filp->f_op = &jmtrd_fops;
printk("[.]in rd_open\n");
return 0;
}
#endif
#ifdef CONFIG_BLK_DEV_INITRD
if (DEVICE_NR(inode->i_rdev) == INITRD_MINOR) {
if (!initrd_start) return -ENODEV;
initrd_users++;
filp->f_op = &initrd_fops;
return 0;
}
#endif
if (DEVICE_NR(inode->i_rdev) >= NUM_RAMDISKS)
return -ENXIO;
MOD_INC_USE_COUNT;
return 0;
}
static int rd_release(struct inode * inode, struct file * filp)
{
MOD_DEC_USE_COUNT;
return 0;
}
static struct file_operations fd_fops = {
NULL, /* lseek - default */
initrd_read,/*block_read, read - block dev read */
block_write, /* write - block dev write */
NULL, /* readdir - not here! */
NULL, /* poll */
rd_ioctl, /* ioctl */
NULL, /* mmap */
rd_open, /* open */
NULL, /* flush */
rd_release, /* module needs to decrement use count */
block_fsync /* fsync */
};
/* This is the registration and initialization section of the RAM disk driver */
__initfunc(int rd_init(void))
{
int i;
#ifdef JMT_RD
if (register_blkdev(MAJOR_NR, "ramdisk", &jmtrd_fops)) {
#else
if (register_blkdev(MAJOR_NR, "ramdisk", &fd_fops)) {
#endif
printk("RAMDISK: Could not get major %d", MAJOR_NR);
return -EIO;
}
blk_dev[MAJOR_NR].request_fn = &rd_request;
for (i = 0; i < NUM_RAMDISKS; i++) {
rd_length[i] = (rd_size * 1024);
rd_blocksizes[i] = 1024;
}
blksize_size[MAJOR_NR] = rd_blocksizes;
printk("RAM disk driver initialized: %d RAM disks of %dK size\n",
NUM_RAMDISKS, rd_size);
return 0;
}
/* loadable module support */
#ifdef MODULE
int init_module(void)
{
int error = rd_init();
if (!error)
printk(KERN_INFO "RAMDISK: Loaded as module.\n");
return error;
}
/* Before freeing the module, invalidate all of the protected buffers! */
void cleanup_module(void)
{
int i;
for (i = 0 ; i < NUM_RAMDISKS; i++)
invalidate_buffers(MKDEV(MAJOR_NR, i));
unregister_blkdev( MAJOR_NR, "ramdisk" );
blk_dev[MAJOR_NR].request_fn = 0;
}
#endif /* MODULE */
/* End of non-loading portions of the RAM disk driver */
#ifdef RD_LOADER
/*
* This routine tries to find a RAM disk image to load, and returns the
* number of blocks to read for a non-compressed image, 0 if the image
* is a compressed image, and -1 if an image with the right magic
* numbers could not be found.
*
* We currently check for the following magic numbers:
* minix
* ext2
* romfs
* gzip
*/
int
identify_romfs_image(void)
{
const int size = 512;
struct romfs_super_block *romfsb;
int nblocks = -1;
unsigned char *buf;
int start_block=0;
loff_t pos;
pos=0;
buf = kmalloc(size, GFP_KERNEL);
if (buf == 0)
return -1;
romfsb = (struct romfs_super_block *) buf;
memset(buf, 0xe5, size);
/*
* Read block 0 to test for romfs image
*/
initrd_read(NULL,buf,size,&pos);
/* romfs is at block zero too */
if (romfsb->word0 == ROMSB_WORD0 &&
romfsb->word1 == ROMSB_WORD1) {
printk(KERN_NOTICE
"RAMDISK: romfs filesystem found at block %d\n",
start_block);
nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
goto done;
}
printk(KERN_NOTICE
"JMTRD: Couldn't find valid ROMFS disk image starting at %d.\n",
start_block);
done:
kfree(buf);
return nblocks;
}
__initfunc(int
identify_ramdisk_image(kdev_t device, struct file *fp, int start_block))
{
const int size = 512;
struct minix_super_block *minixsb;
struct ext2_super_block *ext2sb;
struct romfs_super_block *romfsb;
int nblocks = -1;
unsigned char *buf;
buf = kmalloc(size, GFP_KERNEL);
if (buf == 0)
return -1;
minixsb = (struct minix_super_block *) buf;
ext2sb = (struct ext2_super_block *) buf;
romfsb = (struct romfs_super_block *) buf;
memset(buf, 0xe5, size);
/*
* Read block 0 to test for gzipped kernel
*/
if (fp->f_op->llseek)
fp->f_op->llseek(fp, start_block * BLOCK_SIZE, 0);
fp->f_pos = start_block * BLOCK_SIZE;
fp->f_op->read(fp, buf, size, &fp->f_pos);
/*
* If it matches the gzip magic numbers, return -1
*/
if (buf[0] == 037 && ((buf[1] == 0213) || (buf[1] == 0236))) {
printk(KERN_NOTICE
"RAMDISK: Compressed image found at block %d\n",
start_block);
nblocks = 0;
goto done;
}
/* romfs is at block zero too */
if (romfsb->word0 == ROMSB_WORD0 &&
romfsb->word1 == ROMSB_WORD1) {
printk(KERN_NOTICE
"RAMDISK: romfs filesystem found at block %d\n",
start_block);
nblocks = (ntohl(romfsb->size)+BLOCK_SIZE-1)>>BLOCK_SIZE_BITS;
goto done;
}
/*
* Read block 1 to test for minix and ext2 superblock
*/
if (fp->f_op->llseek)
fp->f_op->llseek(fp, (start_block+1) * BLOCK_SIZE, 0);
fp->f_pos = (start_block+1) * BLOCK_SIZE;
fp->f_op->read(fp, buf, size, &fp->f_pos);
/* Try minix */
if (minixsb->s_magic == MINIX_SUPER_MAGIC ||
minixsb->s_magic == MINIX_SUPER_MAGIC2) {
printk(KERN_NOTICE
"RAMDISK: Minix filesystem found at block %d\n",
start_block);
nblocks = minixsb->s_nzones << minixsb->s_log_zone_size;
goto done;
}
/* Try ext2 */
if (ext2sb->s_magic == cpu_to_le16(EXT2_SUPER_MAGIC)) {
printk(KERN_NOTICE
"RAMDISK: ext2 filesystem found at block %d\n",
start_block);
nblocks = le32_to_cpu(ext2sb->s_blocks_count);
goto done;
}
printk(KERN_NOTICE
"RAMDISK: Couldn't find valid RAM disk image starting at %d.\n",
start_block);
done:
if (fp->f_op->llseek)
fp->f_op->llseek(fp, start_block * BLOCK_SIZE, 0);
fp->f_pos = start_block * BLOCK_SIZE;
kfree(buf);
return nblocks;
}
/*
* This routine loads in the RAM disk image.
*/
#ifdef JMT_RD
__initfunc(static void rd_load_image(kdev_t device,int offset))
{
int nblocks;
nblocks=identify_romfs_image();
ROOT_DEV = MKDEV(MAJOR_NR,0);
printk("[*]jmtrd loaded %d blocks\n",nblocks);
}
#else
__initfunc(static void rd_load_image(kdev_t device,int offset))
{
struct inode inode, out_inode;
struct file infile, outfile;
struct dentry in_dentry, out_dentry;
mm_segment_t fs;
kdev_t ram_device;
int nblocks, i;
char *buf;
unsigned short rotate = 0;
unsigned short devblocks = 0;
char rotator[4] = { '|' , '/' , '-' , '\\' };
ram_device = MKDEV(MAJOR_NR, 0);
memset(&infile, 0, sizeof(infile));
memset(&inode, 0, sizeof(inode));
memset(&in_dentry, 0, sizeof(in_dentry));
inode.i_rdev = device;
infile.f_mode = 1; /* read only */
infile.f_dentry = &in_dentry;
in_dentry.d_inode = &inode;
memset(&outfile, 0, sizeof(outfile));
memset(&out_inode, 0, sizeof(out_inode));
memset(&out_dentry, 0, sizeof(out_dentry));
out_inode.i_rdev = ram_device;
outfile.f_mode = 3; /* read/write */
outfile.f_dentry = &out_dentry;
out_dentry.d_inode = &out_inode;
if (blkdev_open(&inode, &infile) != 0) return;
if (blkdev_open(&out_inode, &outfile) != 0) return;
fs = get_fs();
set_fs(KERNEL_DS);
#if 0
printk("identify_ramdisk_image\n");
#endif
nblocks = identify_ramdisk_image(device, &infile, offset);
#if 0
printk("#nblocks:#%d\n",nblocks);
#endif
if (nblocks < 0)
goto done;
if (nblocks == 0) {
#ifdef BUILD_CRAMDISK
if (crd_load(&infile, &outfile) == 0)
goto successful_load;
#else
printk(KERN_NOTICE
"RAMDISK: Kernel does not support compressed "
"RAM disk images\n");
#endif
goto done;
}
if (nblocks > (rd_length[0] >> BLOCK_SIZE_BITS)) {
printk("RAMDISK: image too big! (%d/%d blocks)\n",
nblocks, rd_length[0] >> BLOCK_SIZE_BITS);
goto done;
}
/*
* OK, time to copy in the data
*/
buf = kmalloc(BLOCK_SIZE, GFP_KERNEL);
if (buf == 0) {
printk(KERN_ERR "RAMDISK: could not allocate buffer\n");
goto done;
}
if (blk_size[MAJOR(device)])
devblocks = blk_size[MAJOR(device)][MINOR(device)];
#ifdef CONFIG_BLK_DEV_INITRD
if (MAJOR(device) == MAJOR_NR && MINOR(device) == INITRD_MINOR)
devblocks = nblocks;
#endif
if (devblocks == 0) {
printk(KERN_ERR "RAMDISK: could not determine device size\n");
goto done;
}
printk(KERN_NOTICE "RAMDISK: Loading %d blocks [%d disk%s] into ram disk... ",
nblocks, ((nblocks-1)/devblocks)+1, nblocks>devblocks ? "s" : "");
for (i=0; i < nblocks; i++) {
if (i && (i % devblocks == 0)) {
printk("done disk #%d.\n", i/devblocks);
rotate = 0;
invalidate_buffers(device);
if (infile.f_op->release)
infile.f_op->release(&inode, &infile);
printk("Please insert disk #%d and press ENTER\n", i/devblocks+1);
wait_for_keypress();
if (blkdev_open(&inode, &infile) != 0) {
printk("Error opening disk.\n");
goto done;
}
infile.f_pos = 0;
printk("Loading disk #%d... ", i/devblocks+1);
}
infile.f_op->read(&infile, buf, BLOCK_SIZE, &infile.f_pos);
outfile.f_op->write(&outfile, buf, BLOCK_SIZE, &outfile.f_pos);
if (!(i % 16)) {
printk("%c\b", rotator[rotate & 0x3]);
rotate++;
}
}
printk("done.\n");
kfree(buf);
successful_load:
invalidate_buffers(device);
printk("[*]old ROOT_DEV=%s\n",kdevname(ROOT_DEV));
ROOT_DEV = MKDEV(MAJOR_NR,0);
done:
if (infile.f_op->release)
infile.f_op->release(&inode, &infile);
set_fs(fs);
}
#endif
__initfunc(void rd_load(void))
{
if (rd_doload == 0)
return;
if (MAJOR(ROOT_DEV) != FLOPPY_MAJOR) return;
if (rd_prompt) {
#ifdef CONFIG_BLK_DEV_FD
floppy_eject();
#endif
printk(KERN_NOTICE
"VFS: Insert root floppy disk to be loaded into RAM disk and press ENTER\n");
wait_for_keypress();
}
rd_load_image(ROOT_DEV,rd_image_start);
}
#ifdef CONFIG_BLK_DEV_INITRD
__initfunc(void initrd_load(void))
{
#if 0
printk("[+]rd_load_image()\n");
#endif
rd_load_image(MKDEV(MAJOR_NR, INITRD_MINOR),0);
}
#endif
#endif /* RD_LOADER */
#ifdef BUILD_CRAMDISK
/*
* gzip declarations
*/
#define OF(args) args
#define memzero(s, n) memset ((s), 0, (n))
typedef unsigned char uch;
typedef unsigned short ush;
typedef unsigned long ulg;
#define INBUFSIZ 4096
#define WSIZE 0x8000 /* window size--must be a power of two, and */
/* at least 32K for zip's deflate method */
static uch *inbuf;
static uch *window;
static unsigned insize = 0; /* valid bytes in inbuf */
static unsigned inptr = 0; /* index of next byte to be processed in inbuf */
static unsigned outcnt = 0; /* bytes in output buffer */
static int exit_code = 0;
static long bytes_out = 0;
static struct file *crd_infp, *crd_outfp;
#define get_byte() (inptr < insize ? inbuf[inptr++] : fill_inbuf())
/* Diagnostic functions (stubbed out) */
#define Assert(cond,msg)
#define Trace(x)
#define Tracev(x)
#define Tracevv(x)
#define Tracec(c,x)
#define Tracecv(c,x)
#define STATIC static
static int fill_inbuf(void);
static void flush_window(void);
static void *malloc(int size);
static void free(void *where);
static void error(char *m);
static void gzip_mark(void **);
static void gzip_release(void **);
#include "../../lib/inflate.c"
__initfunc(static void *malloc(int size))
{
return kmalloc(size, GFP_KERNEL);
}
__initfunc(static void free(void *where))
{
kfree(where);
}
__initfunc(static void gzip_mark(void **ptr))
{
}
__initfunc(static void gzip_release(void **ptr))
{
}
/* ===========================================================================
* Fill the input buffer. This is called only when the buffer is empty
* and at least one byte is really needed.
*/
__initfunc(static int fill_inbuf(void))
{
if (exit_code) return -1;
insize = crd_infp->f_op->read(crd_infp, inbuf, INBUFSIZ,
&crd_infp->f_pos);
if (insize == 0) return -1;
inptr = 1;
return inbuf[0];
}
/* ===========================================================================
* Write the output window window[0..outcnt-1] and update crc and bytes_out.
* (Used for the decompressed data only.)
*/
__initfunc(static void flush_window(void))
{
ulg c = crc; /* temporary variable */
unsigned n;
uch *in, ch;
crd_outfp->f_op->write(crd_outfp, window, outcnt, &crd_outfp->f_pos);
in = window;
for (n = 0; n < outcnt; n++) {
ch = *in++;
c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
}
crc = c;
bytes_out += (ulg)outcnt;
outcnt = 0;
}
__initfunc(static void error(char *x))
{
printk(KERN_ERR "%s", x);
exit_code = 1;
}
__initfunc(static int
crd_load(struct file * fp, struct file *outfp))
{
int result;
crd_infp = fp;
crd_outfp = outfp;
inbuf = kmalloc(INBUFSIZ, GFP_KERNEL);
if (inbuf == 0) {
printk(KERN_ERR "RAMDISK: Couldn't allocate gzip buffer\n");
return -1;
}
window = kmalloc(WSIZE, GFP_KERNEL);
if (window == 0) {
printk(KERN_ERR "RAMDISK: Couldn't allocate gzip window\n");
kfree(inbuf);
return -1;
}
makecrc();
result = gunzip();
kfree(inbuf);
kfree(window);
return result;
}
#endif /* BUILD_CRAMDISK */
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