/* * Parse RedBoot-style Flash Image System (FIS) tables and * produce a Linux partition array to match. * * Copyright © 2001      Red Hat UK Limited * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA * */ #include <linux/kernel.h>#include <linux/slab.h>#include <linux/init.h>#include <linux/vmalloc.h> #include <linux/mtd/mtd.h>#include <linux/mtd/partitions.h>#include <linux/module.h> struct fis_image_desc {    unsigned char name[16];      // Null terminated name    uint32_t	  flash_base;    // Address within FLASH of image    uint32_t	  mem_base;      // Address in memory where it executes    uint32_t	  size;          // Length of image    uint32_t	  entry_point;   // Execution entry point    uint32_t	  data_length;   // Length of actual data    unsigned char _pad[256-(16+7*sizeof(uint32_t))];    uint32_t	  desc_cksum;    // Checksum over image descriptor    uint32_t	  file_cksum;    // Checksum over image data}; struct fis_list {	struct fis_image_desc *img;	struct fis_list *next;}; static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;module_param(directory, int, 0); static inline int redboot_checksum(struct fis_image_desc *img){	/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */	return 1;} static int parse_redboot_partitions(struct mtd_info *master,				    struct mtd_partition **pparts,				    struct mtd_part_parser_data *data){	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;	char *nullname;	int namelen = 0;	int nulllen = 0;	int numslots;	unsigned long offset;#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED	static char nullstring[] = "unallocated";#endif 	if ( directory < 0 ) {		offset = master->size + directory * master->erasesize;		while (mtd_block_isbad(master, offset)) {			if (!offset) {			nogood:				printk(KERN_NOTICE "Failed to find a non-bad block to check for RedBoot partition table\n");				return -EIO;			}			offset -= master->erasesize;		}	} else {		offset = directory * master->erasesize;		while (mtd_block_isbad(master, offset)) {			offset += master->erasesize;			if (offset == master->size)				goto nogood;		}	}	buf = vmalloc(master->erasesize); 	if (!buf)		return -ENOMEM; 	printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",	       master->name, offset); 	ret = mtd_read(master, offset, master->erasesize, &retlen,		       (void *)buf); 	if (ret)		goto out; 	if (retlen != master->erasesize) {		ret = -EIO;		goto out;	} 	numslots = (master->erasesize / sizeof(struct fis_image_desc));	for (i = 0; i < numslots; i++) {		if (!memcmp(buf[i].name, "FIS directory", 14)) {			/* This is apparently the FIS directory entry for the			 * FIS directory itself.  The FIS directory size is			 * one erase block; if the buf[i].size field is			 * swab32(erasesize) then we know we are looking at			 * a byte swapped FIS directory - swap all the entries!			 * (NOTE: this is 'size' not 'data_length'; size is			 * the full size of the entry.)			 */ 			/* RedBoot can combine the FIS directory and			   config partitions into a single eraseblock;			   we assume wrong-endian if either the swapped			   'size' matches the eraseblock size precisely,			   or if the swapped size actually fits in an			   eraseblock while the unswapped size doesn't. */			if (swab32(buf[i].size) == master->erasesize ||			    (buf[i].size > master->erasesize			     && swab32(buf[i].size) < master->erasesize)) {				int j;				/* Update numslots based on actual FIS directory size */				numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc);				for (j = 0; j < numslots; ++j) { 					/* A single 0xff denotes a deleted entry.					 * Two of them in a row is the end of the table.					 */					if (buf[j].name[0] == 0xff) {				  		if (buf[j].name[1] == 0xff) {							break;						} else {							continue;						}					} 					/* The unsigned long fields were written with the					 * wrong byte sex, name and pad have no byte sex.					 */					swab32s(&buf[j].flash_base);					swab32s(&buf[j].mem_base);					swab32s(&buf[j].size);					swab32s(&buf[j].entry_point);					swab32s(&buf[j].data_length);					swab32s(&buf[j].desc_cksum);					swab32s(&buf[j].file_cksum);				}			} else if (buf[i].size < master->erasesize) {				/* Update numslots based on actual FIS directory size */				numslots = buf[i].size / sizeof(struct fis_image_desc);			}			break;		}	}	if (i == numslots) {		/* 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 < numslots; i++) {		struct fis_list *new_fl, **prev; 		if (buf[i].name[0] == 0xff) {			if (buf[i].name[1] == 0xff) {				break;			} else {				continue;			}		}		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];		if (data && data->origin)			buf[i].flash_base -= data->origin;		else			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++;	}#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED	if (fl->img->flash_base) {		nrparts++;		nulllen = sizeof(nullstring);	} 	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++;			nulllen = sizeof(nullstring);		}	}#endif	parts = kzalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL); 	if (!parts) {		ret = -ENOMEM;		goto out;	} 	nullname = (char *)&parts[nrparts];#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED	if (nulllen > 0) {		strcpy(nullname, nullstring);	}#endif	names = nullname + nulllen; 	i=0; #ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED	if (fl->img->flash_base) {	       parts[0].name = nullname;	       parts[0].size = fl->img->flash_base;	       parts[0].offset = 0;		i++;	}#endif	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);#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY		if (!memcmp(names, "RedBoot", 8) ||				!memcmp(names, "RedBoot config", 15) ||				!memcmp(names, "FIS directory", 14)) {			parts[i].mask_flags = MTD_WRITEABLE;		}#endif		names += strlen(names)+1; #ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED		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 = nullname;		}#endif		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);	}	vfree(buf);	return ret;} static struct mtd_part_parser redboot_parser = {	.owner = THIS_MODULE,	.parse_fn = parse_redboot_partitions,	.name = "RedBoot",}; /* mtd parsers will request the module by parser name */MODULE_ALIAS("RedBoot"); static int __init redboot_parser_init(void){	return register_mtd_parser(&redboot_parser);} static void __exit redboot_parser_exit(void){	deregister_mtd_parser(&redboot_parser);} module_init(redboot_parser_init);module_exit(redboot_parser_exit); MODULE_LICENSE("GPL");MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");