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/*
* $Id: redboot.c,v 1.6 2001/10/25 09:16:06 dwmw2 Exp $
*
* Parse RedBoot-style Flash Image System (FIS) tables and
* produce a Linux partition array to match.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
struct fis_image_desc {
unsigned char name[16]; // Null terminated name
unsigned long flash_base; // Address within FLASH of image
unsigned long mem_base; // Address in memory where it executes
unsigned long size; // Length of image
unsigned long entry_point; // Execution entry point
unsigned long data_length; // Length of actual data
unsigned char _pad[256-(16+7*sizeof(unsigned long))];
unsigned long desc_cksum; // Checksum over image descriptor
unsigned long file_cksum; // Checksum over image data
};
struct fis_list {
struct fis_image_desc *img;
struct fis_list *next;
};
static inline int redboot_checksum(struct fis_image_desc *img)
{
/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
return 1;
}
int parse_redboot_partitions(struct mtd_info *master, struct mtd_partition **pparts)
{
int nrparts = 0;
struct fis_image_desc *buf;
struct mtd_partition *parts;
struct fis_list *fl = NULL, *tmp_fl;
int ret, i;
size_t retlen;
char *names;
int namelen = 0;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
/* Read the start of the last erase block */
ret = master->read(master, master->size - master->erasesize,
PAGE_SIZE, &retlen, (void *)buf);
if (ret)
goto out;
if (retlen != PAGE_SIZE) {
ret = -EIO;
goto out;
}
/* RedBoot image could appear in any of the first three slots */
for (i = 0; i < 3; i++) {
if (!memcmp(buf[i].name, "RedBoot", 8))
break;
}
if (i == 3) {
/* Didn't find it */
printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
master->name);
ret = 0;
goto out;
}
for (i = 0; i < PAGE_SIZE / sizeof(struct fis_image_desc); i++) {
struct fis_list *new_fl, **prev;
if (buf[i].name[0] == 0xff)
break;
if (!redboot_checksum(&buf[i]))
break;
new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
namelen += strlen(buf[i].name)+1;
if (!new_fl) {
ret = -ENOMEM;
goto out;
}
new_fl->img = &buf[i];
buf[i].flash_base &= master->size-1;
/* I'm sure the JFFS2 code has done me permanent damage.
* I now think the following is _normal_
*/
prev = &fl;
while(*prev && (*prev)->img->flash_base < new_fl->img->flash_base)
prev = &(*prev)->next;
new_fl->next = *prev;
*prev = new_fl;
nrparts++;
}
if (fl->img->flash_base)
nrparts++;
for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize < tmp_fl->next->img->flash_base)
nrparts++;
}
parts = kmalloc(sizeof(*parts)*nrparts + namelen, GFP_KERNEL);
if (!parts) {
ret = -ENOMEM;
goto out;
}
names = (char *)&parts[nrparts];
memset(parts, 0, sizeof(*parts)*nrparts + namelen);
i=0;
if (fl->img->flash_base) {
parts[0].name = "unallocated space";
parts[0].size = fl->img->flash_base;
parts[0].offset = 0;
}
for ( ; i<nrparts; i++) {
parts[i].size = fl->img->size;
parts[i].offset = fl->img->flash_base;
parts[i].name = names;
strcpy(names, fl->img->name);
names += strlen(names)+1;
if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize < fl->next->img->flash_base) {
i++;
parts[i].offset = parts[i-1].size + parts[i-1].offset;
parts[i].size = fl->next->img->flash_base - parts[i].offset;
parts[i].name = "unallocated space";
}
tmp_fl = fl;
fl = fl->next;
kfree(tmp_fl);
}
ret = nrparts;
*pparts = parts;
out:
while (fl) {
struct fis_list *old = fl;
fl = fl->next;
kfree(old);
}
kfree(buf);
return ret;
}
EXPORT_SYMBOL(parse_redboot_partitions);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Red Hat, Inc. - David Woodhouse <dwmw2@cambridge.redhat.com>");
MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");
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