linux/drivers/mtd/cmdlinepart.c
Atsushi Nemoto 17b536cc43 [MTD] mtdpart: Make all partition parsers return allocated array
Currently redboot and afx parser return allocated mtd_partition array
and cmdlinepart and ar7 return persistent array.

This patch make cmdlinepart and ar7 also return allocated array, so
that all users can free it regardless of parser type.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-03-20 18:55:17 +00:00

381 lines
9.2 KiB
C

/*
* Read flash partition table from command line
*
* Copyright 2002 SYSGO Real-Time Solutions GmbH
*
* The format for the command line is as follows:
*
* mtdparts=<mtddef>[;<mtddef]
* <mtddef> := <mtd-id>:<partdef>[,<partdef>]
* where <mtd-id> is the name from the "cat /proc/mtd" command
* <partdef> := <size>[@offset][<name>][ro][lk]
* <mtd-id> := unique name used in mapping driver/device (mtd->name)
* <size> := standard linux memsize OR "-" to denote all remaining space
* <name> := '(' NAME ')'
*
* Examples:
*
* 1 NOR Flash, with 1 single writable partition:
* edb7312-nor:-
*
* 1 NOR Flash with 2 partitions, 1 NAND with one
* edb7312-nor:256k(ARMboot)ro,-(root);edb7312-nand:-(home)
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/bootmem.h>
/* error message prefix */
#define ERRP "mtd: "
/* debug macro */
#if 0
#define dbg(x) do { printk("DEBUG-CMDLINE-PART: "); printk x; } while(0)
#else
#define dbg(x)
#endif
/* special size referring to all the remaining space in a partition */
#define SIZE_REMAINING UINT_MAX
#define OFFSET_CONTINUOUS UINT_MAX
struct cmdline_mtd_partition {
struct cmdline_mtd_partition *next;
char *mtd_id;
int num_parts;
struct mtd_partition *parts;
};
/* mtdpart_setup() parses into here */
static struct cmdline_mtd_partition *partitions;
/* the command line passed to mtdpart_setupd() */
static char *cmdline;
static int cmdline_parsed = 0;
/*
* Parse one partition definition for an MTD. Since there can be many
* comma separated partition definitions, this function calls itself
* recursively until no more partition definitions are found. Nice side
* effect: the memory to keep the mtd_partition structs and the names
* is allocated upon the last definition being found. At that point the
* syntax has been verified ok.
*/
static struct mtd_partition * newpart(char *s,
char **retptr,
int *num_parts,
int this_part,
unsigned char **extra_mem_ptr,
int extra_mem_size)
{
struct mtd_partition *parts;
unsigned long size;
unsigned long offset = OFFSET_CONTINUOUS;
char *name;
int name_len;
unsigned char *extra_mem;
char delim;
unsigned int mask_flags;
/* fetch the partition size */
if (*s == '-')
{ /* assign all remaining space to this partition */
size = SIZE_REMAINING;
s++;
}
else
{
size = memparse(s, &s);
if (size < PAGE_SIZE)
{
printk(KERN_ERR ERRP "partition size too small (%lx)\n", size);
return NULL;
}
}
/* fetch partition name and flags */
mask_flags = 0; /* this is going to be a regular partition */
delim = 0;
/* check for offset */
if (*s == '@')
{
s++;
offset = memparse(s, &s);
}
/* now look for name */
if (*s == '(')
{
delim = ')';
}
if (delim)
{
char *p;
name = ++s;
p = strchr(name, delim);
if (!p)
{
printk(KERN_ERR ERRP "no closing %c found in partition name\n", delim);
return NULL;
}
name_len = p - name;
s = p + 1;
}
else
{
name = NULL;
name_len = 13; /* Partition_000 */
}
/* record name length for memory allocation later */
extra_mem_size += name_len + 1;
/* test for options */
if (strncmp(s, "ro", 2) == 0)
{
mask_flags |= MTD_WRITEABLE;
s += 2;
}
/* if lk is found do NOT unlock the MTD partition*/
if (strncmp(s, "lk", 2) == 0)
{
mask_flags |= MTD_POWERUP_LOCK;
s += 2;
}
/* test if more partitions are following */
if (*s == ',')
{
if (size == SIZE_REMAINING)
{
printk(KERN_ERR ERRP "no partitions allowed after a fill-up partition\n");
return NULL;
}
/* more partitions follow, parse them */
parts = newpart(s + 1, &s, num_parts, this_part + 1,
&extra_mem, extra_mem_size);
if (!parts)
return NULL;
}
else
{ /* this is the last partition: allocate space for all */
int alloc_size;
*num_parts = this_part + 1;
alloc_size = *num_parts * sizeof(struct mtd_partition) +
extra_mem_size;
parts = kzalloc(alloc_size, GFP_KERNEL);
if (!parts)
{
printk(KERN_ERR ERRP "out of memory\n");
return NULL;
}
extra_mem = (unsigned char *)(parts + *num_parts);
}
/* enter this partition (offset will be calculated later if it is zero at this point) */
parts[this_part].size = size;
parts[this_part].offset = offset;
parts[this_part].mask_flags = mask_flags;
if (name)
{
strlcpy(extra_mem, name, name_len + 1);
}
else
{
sprintf(extra_mem, "Partition_%03d", this_part);
}
parts[this_part].name = extra_mem;
extra_mem += name_len + 1;
dbg(("partition %d: name <%s>, offset %x, size %x, mask flags %x\n",
this_part,
parts[this_part].name,
parts[this_part].offset,
parts[this_part].size,
parts[this_part].mask_flags));
/* return (updated) pointer to extra_mem memory */
if (extra_mem_ptr)
*extra_mem_ptr = extra_mem;
/* return (updated) pointer command line string */
*retptr = s;
/* return partition table */
return parts;
}
/*
* Parse the command line.
*/
static int mtdpart_setup_real(char *s)
{
cmdline_parsed = 1;
for( ; s != NULL; )
{
struct cmdline_mtd_partition *this_mtd;
struct mtd_partition *parts;
int mtd_id_len;
int num_parts;
char *p, *mtd_id;
mtd_id = s;
/* fetch <mtd-id> */
if (!(p = strchr(s, ':')))
{
printk(KERN_ERR ERRP "no mtd-id\n");
return 0;
}
mtd_id_len = p - mtd_id;
dbg(("parsing <%s>\n", p+1));
/*
* parse one mtd. have it reserve memory for the
* struct cmdline_mtd_partition and the mtd-id string.
*/
parts = newpart(p + 1, /* cmdline */
&s, /* out: updated cmdline ptr */
&num_parts, /* out: number of parts */
0, /* first partition */
(unsigned char**)&this_mtd, /* out: extra mem */
mtd_id_len + 1 + sizeof(*this_mtd) +
sizeof(void*)-1 /*alignment*/);
if(!parts)
{
/*
* An error occurred. We're either:
* a) out of memory, or
* b) in the middle of the partition spec
* Either way, this mtd is hosed and we're
* unlikely to succeed in parsing any more
*/
return 0;
}
/* align this_mtd */
this_mtd = (struct cmdline_mtd_partition *)
ALIGN((unsigned long)this_mtd, sizeof(void*));
/* enter results */
this_mtd->parts = parts;
this_mtd->num_parts = num_parts;
this_mtd->mtd_id = (char*)(this_mtd + 1);
strlcpy(this_mtd->mtd_id, mtd_id, mtd_id_len + 1);
/* link into chain */
this_mtd->next = partitions;
partitions = this_mtd;
dbg(("mtdid=<%s> num_parts=<%d>\n",
this_mtd->mtd_id, this_mtd->num_parts));
/* EOS - we're done */
if (*s == 0)
break;
/* does another spec follow? */
if (*s != ';')
{
printk(KERN_ERR ERRP "bad character after partition (%c)\n", *s);
return 0;
}
s++;
}
return 1;
}
/*
* Main function to be called from the MTD mapping driver/device to
* obtain the partitioning information. At this point the command line
* arguments will actually be parsed and turned to struct mtd_partition
* information. It returns partitions for the requested mtd device, or
* the first one in the chain if a NULL mtd_id is passed in.
*/
static int parse_cmdline_partitions(struct mtd_info *master,
struct mtd_partition **pparts,
unsigned long origin)
{
unsigned long offset;
int i;
struct cmdline_mtd_partition *part;
const char *mtd_id = master->name;
/* parse command line */
if (!cmdline_parsed)
mtdpart_setup_real(cmdline);
for(part = partitions; part; part = part->next)
{
if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id)))
{
for(i = 0, offset = 0; i < part->num_parts; i++)
{
if (part->parts[i].offset == OFFSET_CONTINUOUS)
part->parts[i].offset = offset;
else
offset = part->parts[i].offset;
if (part->parts[i].size == SIZE_REMAINING)
part->parts[i].size = master->size - offset;
if (offset + part->parts[i].size > master->size)
{
printk(KERN_WARNING ERRP
"%s: partitioning exceeds flash size, truncating\n",
part->mtd_id);
part->parts[i].size = master->size - offset;
part->num_parts = i;
}
offset += part->parts[i].size;
}
*pparts = kmemdup(part->parts,
sizeof(*part->parts) * part->num_parts,
GFP_KERNEL);
if (!*pparts)
return -ENOMEM;
return part->num_parts;
}
}
return 0;
}
/*
* This is the handler for our kernel parameter, called from
* main.c::checksetup(). Note that we can not yet kmalloc() anything,
* so we only save the commandline for later processing.
*
* This function needs to be visible for bootloaders.
*/
static int mtdpart_setup(char *s)
{
cmdline = s;
return 1;
}
__setup("mtdparts=", mtdpart_setup);
static struct mtd_part_parser cmdline_parser = {
.owner = THIS_MODULE,
.parse_fn = parse_cmdline_partitions,
.name = "cmdlinepart",
};
static int __init cmdline_parser_init(void)
{
return register_mtd_parser(&cmdline_parser);
}
module_init(cmdline_parser_init);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
MODULE_DESCRIPTION("Command line configuration of MTD partitions");