tmp_suning_uos_patched/drivers/mtd/mtdpart.c
Richard Purdie 388bbb09b9 [MTD] Add mtd panic_write function pointer
MTDs are well suited for logging critical data and the mtdoops driver
allows kernel panics/oops to be written to flash in a blackbox flight
recorder fashion allowing better debugging and analysis of crashes.

Any kernel oops in user context can be easily handled since the kernel
continues as normal and any queued mtd writes are scheduled. Any kernel
oops in interrupt context results in a panic and the delayed writes will
not be scheduled however. The existing mtd->write function cannot be
called in interrupt context so these messages can never be written to
flash.

This patch adds a panic_write function pointer that drivers can
optionally implement which can be called in interrupt context. It is
only intended to be called when its known the kernel is about to panic
and we need to write to succeed. Since the kernel is not going to be
running for much longer, this function can break locks and delay to
ensure the write succeeds (but not sleep).

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2008-02-07 10:30:48 +00:00

580 lines
15 KiB
C

/*
* Simple MTD partitioning layer
*
* (C) 2000 Nicolas Pitre <nico@cam.org>
*
* This code is GPL
*
* $Id: mtdpart.c,v 1.55 2005/11/07 11:14:20 gleixner Exp $
*
* 02-21-2002 Thomas Gleixner <gleixner@autronix.de>
* added support for read_oob, write_oob
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/kmod.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/compatmac.h>
/* Our partition linked list */
static LIST_HEAD(mtd_partitions);
/* Our partition node structure */
struct mtd_part {
struct mtd_info mtd;
struct mtd_info *master;
u_int32_t offset;
int index;
struct list_head list;
int registered;
};
/*
* Given a pointer to the MTD object in the mtd_part structure, we can retrieve
* the pointer to that structure with this macro.
*/
#define PART(x) ((struct mtd_part *)(x))
/*
* MTD methods which simply translate the effective address and pass through
* to the _real_ device.
*/
static int part_read (struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct mtd_part *part = PART(mtd);
int res;
if (from >= mtd->size)
len = 0;
else if (from + len > mtd->size)
len = mtd->size - from;
res = part->master->read (part->master, from + part->offset,
len, retlen, buf);
if (unlikely(res)) {
if (res == -EUCLEAN)
mtd->ecc_stats.corrected++;
if (res == -EBADMSG)
mtd->ecc_stats.failed++;
}
return res;
}
static int part_point (struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char **buf)
{
struct mtd_part *part = PART(mtd);
if (from >= mtd->size)
len = 0;
else if (from + len > mtd->size)
len = mtd->size - from;
return part->master->point (part->master, from + part->offset,
len, retlen, buf);
}
static void part_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from, size_t len)
{
struct mtd_part *part = PART(mtd);
part->master->unpoint (part->master, addr, from + part->offset, len);
}
static int part_read_oob(struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops)
{
struct mtd_part *part = PART(mtd);
int res;
if (from >= mtd->size)
return -EINVAL;
if (ops->datbuf && from + ops->len > mtd->size)
return -EINVAL;
res = part->master->read_oob(part->master, from + part->offset, ops);
if (unlikely(res)) {
if (res == -EUCLEAN)
mtd->ecc_stats.corrected++;
if (res == -EBADMSG)
mtd->ecc_stats.failed++;
}
return res;
}
static int part_read_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct mtd_part *part = PART(mtd);
return part->master->read_user_prot_reg (part->master, from,
len, retlen, buf);
}
static int part_get_user_prot_info (struct mtd_info *mtd,
struct otp_info *buf, size_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->get_user_prot_info (part->master, buf, len);
}
static int part_read_fact_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct mtd_part *part = PART(mtd);
return part->master->read_fact_prot_reg (part->master, from,
len, retlen, buf);
}
static int part_get_fact_prot_info (struct mtd_info *mtd,
struct otp_info *buf, size_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->get_fact_prot_info (part->master, buf, len);
}
static int part_write (struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct mtd_part *part = PART(mtd);
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (to >= mtd->size)
len = 0;
else if (to + len > mtd->size)
len = mtd->size - to;
return part->master->write (part->master, to + part->offset,
len, retlen, buf);
}
static int part_panic_write (struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct mtd_part *part = PART(mtd);
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (to >= mtd->size)
len = 0;
else if (to + len > mtd->size)
len = mtd->size - to;
return part->master->panic_write (part->master, to + part->offset,
len, retlen, buf);
}
static int part_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
struct mtd_part *part = PART(mtd);
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (to >= mtd->size)
return -EINVAL;
if (ops->datbuf && to + ops->len > mtd->size)
return -EINVAL;
return part->master->write_oob(part->master, to + part->offset, ops);
}
static int part_write_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct mtd_part *part = PART(mtd);
return part->master->write_user_prot_reg (part->master, from,
len, retlen, buf);
}
static int part_lock_user_prot_reg (struct mtd_info *mtd, loff_t from, size_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->lock_user_prot_reg (part->master, from, len);
}
static int part_writev (struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen)
{
struct mtd_part *part = PART(mtd);
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
return part->master->writev (part->master, vecs, count,
to + part->offset, retlen);
}
static int part_erase (struct mtd_info *mtd, struct erase_info *instr)
{
struct mtd_part *part = PART(mtd);
int ret;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (instr->addr >= mtd->size)
return -EINVAL;
instr->addr += part->offset;
ret = part->master->erase(part->master, instr);
if (ret) {
if (instr->fail_addr != 0xffffffff)
instr->fail_addr -= part->offset;
instr->addr -= part->offset;
}
return ret;
}
void mtd_erase_callback(struct erase_info *instr)
{
if (instr->mtd->erase == part_erase) {
struct mtd_part *part = PART(instr->mtd);
if (instr->fail_addr != 0xffffffff)
instr->fail_addr -= part->offset;
instr->addr -= part->offset;
}
if (instr->callback)
instr->callback(instr);
}
EXPORT_SYMBOL_GPL(mtd_erase_callback);
static int part_lock (struct mtd_info *mtd, loff_t ofs, size_t len)
{
struct mtd_part *part = PART(mtd);
if ((len + ofs) > mtd->size)
return -EINVAL;
return part->master->lock(part->master, ofs + part->offset, len);
}
static int part_unlock (struct mtd_info *mtd, loff_t ofs, size_t len)
{
struct mtd_part *part = PART(mtd);
if ((len + ofs) > mtd->size)
return -EINVAL;
return part->master->unlock(part->master, ofs + part->offset, len);
}
static void part_sync(struct mtd_info *mtd)
{
struct mtd_part *part = PART(mtd);
part->master->sync(part->master);
}
static int part_suspend(struct mtd_info *mtd)
{
struct mtd_part *part = PART(mtd);
return part->master->suspend(part->master);
}
static void part_resume(struct mtd_info *mtd)
{
struct mtd_part *part = PART(mtd);
part->master->resume(part->master);
}
static int part_block_isbad (struct mtd_info *mtd, loff_t ofs)
{
struct mtd_part *part = PART(mtd);
if (ofs >= mtd->size)
return -EINVAL;
ofs += part->offset;
return part->master->block_isbad(part->master, ofs);
}
static int part_block_markbad (struct mtd_info *mtd, loff_t ofs)
{
struct mtd_part *part = PART(mtd);
int res;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (ofs >= mtd->size)
return -EINVAL;
ofs += part->offset;
res = part->master->block_markbad(part->master, ofs);
if (!res)
mtd->ecc_stats.badblocks++;
return res;
}
/*
* This function unregisters and destroy all slave MTD objects which are
* attached to the given master MTD object.
*/
int del_mtd_partitions(struct mtd_info *master)
{
struct list_head *node;
struct mtd_part *slave;
for (node = mtd_partitions.next;
node != &mtd_partitions;
node = node->next) {
slave = list_entry(node, struct mtd_part, list);
if (slave->master == master) {
struct list_head *prev = node->prev;
__list_del(prev, node->next);
if(slave->registered)
del_mtd_device(&slave->mtd);
kfree(slave);
node = prev;
}
}
return 0;
}
/*
* This function, given a master MTD object and a partition table, creates
* and registers slave MTD objects which are bound to the master according to
* the partition definitions.
* (Q: should we register the master MTD object as well?)
*/
int add_mtd_partitions(struct mtd_info *master,
const struct mtd_partition *parts,
int nbparts)
{
struct mtd_part *slave;
u_int32_t cur_offset = 0;
int i;
printk (KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
for (i = 0; i < nbparts; i++) {
/* allocate the partition structure */
slave = kzalloc (sizeof(*slave), GFP_KERNEL);
if (!slave) {
printk ("memory allocation error while creating partitions for \"%s\"\n",
master->name);
del_mtd_partitions(master);
return -ENOMEM;
}
list_add(&slave->list, &mtd_partitions);
/* set up the MTD object for this partition */
slave->mtd.type = master->type;
slave->mtd.flags = master->flags & ~parts[i].mask_flags;
slave->mtd.size = parts[i].size;
slave->mtd.writesize = master->writesize;
slave->mtd.oobsize = master->oobsize;
slave->mtd.oobavail = master->oobavail;
slave->mtd.subpage_sft = master->subpage_sft;
slave->mtd.name = parts[i].name;
slave->mtd.owner = master->owner;
slave->mtd.read = part_read;
slave->mtd.write = part_write;
if (master->panic_write)
slave->mtd.panic_write = part_panic_write;
if(master->point && master->unpoint){
slave->mtd.point = part_point;
slave->mtd.unpoint = part_unpoint;
}
if (master->read_oob)
slave->mtd.read_oob = part_read_oob;
if (master->write_oob)
slave->mtd.write_oob = part_write_oob;
if(master->read_user_prot_reg)
slave->mtd.read_user_prot_reg = part_read_user_prot_reg;
if(master->read_fact_prot_reg)
slave->mtd.read_fact_prot_reg = part_read_fact_prot_reg;
if(master->write_user_prot_reg)
slave->mtd.write_user_prot_reg = part_write_user_prot_reg;
if(master->lock_user_prot_reg)
slave->mtd.lock_user_prot_reg = part_lock_user_prot_reg;
if(master->get_user_prot_info)
slave->mtd.get_user_prot_info = part_get_user_prot_info;
if(master->get_fact_prot_info)
slave->mtd.get_fact_prot_info = part_get_fact_prot_info;
if (master->sync)
slave->mtd.sync = part_sync;
if (!i && master->suspend && master->resume) {
slave->mtd.suspend = part_suspend;
slave->mtd.resume = part_resume;
}
if (master->writev)
slave->mtd.writev = part_writev;
if (master->lock)
slave->mtd.lock = part_lock;
if (master->unlock)
slave->mtd.unlock = part_unlock;
if (master->block_isbad)
slave->mtd.block_isbad = part_block_isbad;
if (master->block_markbad)
slave->mtd.block_markbad = part_block_markbad;
slave->mtd.erase = part_erase;
slave->master = master;
slave->offset = parts[i].offset;
slave->index = i;
if (slave->offset == MTDPART_OFS_APPEND)
slave->offset = cur_offset;
if (slave->offset == MTDPART_OFS_NXTBLK) {
slave->offset = cur_offset;
if ((cur_offset % master->erasesize) != 0) {
/* Round up to next erasesize */
slave->offset = ((cur_offset / master->erasesize) + 1) * master->erasesize;
printk(KERN_NOTICE "Moving partition %d: "
"0x%08x -> 0x%08x\n", i,
cur_offset, slave->offset);
}
}
if (slave->mtd.size == MTDPART_SIZ_FULL)
slave->mtd.size = master->size - slave->offset;
cur_offset = slave->offset + slave->mtd.size;
printk (KERN_NOTICE "0x%08x-0x%08x : \"%s\"\n", slave->offset,
slave->offset + slave->mtd.size, slave->mtd.name);
/* let's do some sanity checks */
if (slave->offset >= master->size) {
/* let's register it anyway to preserve ordering */
slave->offset = 0;
slave->mtd.size = 0;
printk ("mtd: partition \"%s\" is out of reach -- disabled\n",
parts[i].name);
}
if (slave->offset + slave->mtd.size > master->size) {
slave->mtd.size = master->size - slave->offset;
printk ("mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#x\n",
parts[i].name, master->name, slave->mtd.size);
}
if (master->numeraseregions>1) {
/* Deal with variable erase size stuff */
int i;
struct mtd_erase_region_info *regions = master->eraseregions;
/* Find the first erase regions which is part of this partition. */
for (i=0; i < master->numeraseregions && slave->offset >= regions[i].offset; i++)
;
for (i--; i < master->numeraseregions && slave->offset + slave->mtd.size > regions[i].offset; i++) {
if (slave->mtd.erasesize < regions[i].erasesize) {
slave->mtd.erasesize = regions[i].erasesize;
}
}
} else {
/* Single erase size */
slave->mtd.erasesize = master->erasesize;
}
if ((slave->mtd.flags & MTD_WRITEABLE) &&
(slave->offset % slave->mtd.erasesize)) {
/* Doesn't start on a boundary of major erase size */
/* FIXME: Let it be writable if it is on a boundary of _minor_ erase size though */
slave->mtd.flags &= ~MTD_WRITEABLE;
printk ("mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
parts[i].name);
}
if ((slave->mtd.flags & MTD_WRITEABLE) &&
(slave->mtd.size % slave->mtd.erasesize)) {
slave->mtd.flags &= ~MTD_WRITEABLE;
printk ("mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
parts[i].name);
}
slave->mtd.ecclayout = master->ecclayout;
if (master->block_isbad) {
uint32_t offs = 0;
while(offs < slave->mtd.size) {
if (master->block_isbad(master,
offs + slave->offset))
slave->mtd.ecc_stats.badblocks++;
offs += slave->mtd.erasesize;
}
}
if(parts[i].mtdp)
{ /* store the object pointer (caller may or may not register it */
*parts[i].mtdp = &slave->mtd;
slave->registered = 0;
}
else
{
/* register our partition */
add_mtd_device(&slave->mtd);
slave->registered = 1;
}
}
return 0;
}
EXPORT_SYMBOL(add_mtd_partitions);
EXPORT_SYMBOL(del_mtd_partitions);
static DEFINE_SPINLOCK(part_parser_lock);
static LIST_HEAD(part_parsers);
static struct mtd_part_parser *get_partition_parser(const char *name)
{
struct list_head *this;
void *ret = NULL;
spin_lock(&part_parser_lock);
list_for_each(this, &part_parsers) {
struct mtd_part_parser *p = list_entry(this, struct mtd_part_parser, list);
if (!strcmp(p->name, name) && try_module_get(p->owner)) {
ret = p;
break;
}
}
spin_unlock(&part_parser_lock);
return ret;
}
int register_mtd_parser(struct mtd_part_parser *p)
{
spin_lock(&part_parser_lock);
list_add(&p->list, &part_parsers);
spin_unlock(&part_parser_lock);
return 0;
}
int deregister_mtd_parser(struct mtd_part_parser *p)
{
spin_lock(&part_parser_lock);
list_del(&p->list);
spin_unlock(&part_parser_lock);
return 0;
}
int parse_mtd_partitions(struct mtd_info *master, const char **types,
struct mtd_partition **pparts, unsigned long origin)
{
struct mtd_part_parser *parser;
int ret = 0;
for ( ; ret <= 0 && *types; types++) {
parser = get_partition_parser(*types);
#ifdef CONFIG_KMOD
if (!parser && !request_module("%s", *types))
parser = get_partition_parser(*types);
#endif
if (!parser) {
printk(KERN_NOTICE "%s partition parsing not available\n",
*types);
continue;
}
ret = (*parser->parse_fn)(master, pparts, origin);
if (ret > 0) {
printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
ret, parser->name, master->name);
}
put_partition_parser(parser);
}
return ret;
}
EXPORT_SYMBOL_GPL(parse_mtd_partitions);
EXPORT_SYMBOL_GPL(register_mtd_parser);
EXPORT_SYMBOL_GPL(deregister_mtd_parser);