u-boot/drivers/mtd/mtdpart.c

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/*
* Simple MTD partitioning layer
*
* Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
* Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
* Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
*
* SPDX-License-Identifier: GPL-2.0+
*
*/
#ifndef __UBOOT__
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/kmod.h>
#endif
#include <common.h>
#include <malloc.h>
#include <asm/errno.h>
#include <linux/compat.h>
#include <ubi_uboot.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/err.h>
#include "mtdcore.h"
/* Our partition linked list */
static LIST_HEAD(mtd_partitions);
#ifndef __UBOOT__
static DEFINE_MUTEX(mtd_partitions_mutex);
#else
DEFINE_MUTEX(mtd_partitions_mutex);
#endif
/* Our partition node structure */
struct mtd_part {
struct mtd_info mtd;
struct mtd_info *master;
uint64_t offset;
struct list_head list;
};
/*
* 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))
#ifdef __UBOOT__
/* from mm/util.c */
/**
* kstrdup - allocate space for and copy an existing string
* @s: the string to duplicate
* @gfp: the GFP mask used in the kmalloc() call when allocating memory
*/
char *kstrdup(const char *s, gfp_t gfp)
{
size_t len;
char *buf;
if (!s)
return NULL;
len = strlen(s) + 1;
buf = kmalloc(len, gfp);
if (buf)
memcpy(buf, s, len);
return buf;
}
#endif
/*
* 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);
struct mtd_ecc_stats stats;
int res;
stats = part->master->ecc_stats;
res = part->master->_read(part->master, from + part->offset, len,
retlen, buf);
mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN Linux modified the MTD driver interface in commit edbc4540 (with the same name as this commit). The effect is that calls to mtd_read will not return -EUCLEAN if the number of ECC-corrected bit errors is below a certain threshold, which defaults to the strength of the ECC. This allows -EUCLEAN to stop indicating "some bits were corrected" and begin indicating "a large number of bits were corrected, the data held in this region of flash may be lost soon". UBI makes use of this and when -EUCLEAN is returned from mtd_read it will move data to another block of flash. Without adopting this interface change UBI on U-boot attempts to move data between blocks every time a single bit is corrected using the ECC, which is a very common occurance on some devices. For some devices where bit errors are common enough, UBI can get stuck constantly moving data around because each block it attempts to use has a single bit error. This condition is hit when wear_leveling_worker attempts to move data from one PEB to another in response to an -EUCLEAN/UBI_IO_BITFLIPS error. When this happens ubi_eba_copy_leb is called to perform the data copy, and after the data is written it is read back to check its validity. If that read returns UBI_IO_BITFLIPS (in response to an MTD -EUCLEAN) then ubi_eba_copy_leb returns 1 to wear_leveling worker, which then proceeds to schedule the destination PEB for erasure. This leads to erase_worker running on the PEB, and following a successful erase wear_leveling_worker is called which begins this whole cycle all over again. The end result is that (without UBI debug output enabled) the boot appears to simply hang whilst in reality U-boot busily works away at destroying a block of the NAND flash. Debug output from this situation: UBI DBG: ensure_wear_leveling: schedule scrubbing UBI DBG: wear_leveling_worker: scrub PEB 1027 to PEB 4083 UBI DBG: ubi_io_read_vid_hdr: read VID header from PEB 1027 UBI DBG: ubi_io_read: read 4096 bytes from PEB 1027:4096 UBI DBG: ubi_eba_copy_leb: copy LEB 0:0, PEB 1027 to PEB 4083 UBI DBG: ubi_eba_copy_leb: read 1040384 bytes of data UBI DBG: ubi_io_read: read 1040384 bytes from PEB 1027:8192 UBI: fixable bit-flip detected at PEB 1027 UBI DBG: ubi_io_write_vid_hdr: write VID header to PEB 4083 UBI DBG: ubi_io_write: write 4096 bytes to PEB 4083:4096 UBI DBG: ubi_io_read_vid_hdr: read VID header from PEB 4083 UBI DBG: ubi_io_read: read 4096 bytes from PEB 4083:4096 UBI DBG: ubi_io_write: write 4096 bytes to PEB 4083:8192 UBI DBG: ubi_io_read: read 4096 bytes from PEB 4083:8192 UBI: fixable bit-flip detected at PEB 4083 UBI DBG: schedule_erase: schedule erasure of PEB 4083, EC 55, torture 0 UBI DBG: erase_worker: erase PEB 4083 EC 55 UBI DBG: sync_erase: erase PEB 4083, old EC 55 UBI DBG: do_sync_erase: erase PEB 4083 UBI DBG: sync_erase: erased PEB 4083, new EC 56 UBI DBG: ubi_io_write_ec_hdr: write EC header to PEB 4083 UBI DBG: ubi_io_write: write 4096 bytes to PEB 4083:0 UBI DBG: ensure_wear_leveling: schedule scrubbing UBI DBG: wear_leveling_worker: scrub PEB 1027 to PEB 4083 ... This patch adopts the interface change as in Linux commit edbc4540 in order to avoid such situations. Given that none of the drivers under drivers/mtd return -EUCLEAN, this should only affect those using software ECC. I have tested that it works on a board which is currently out of tree, but which I hope to be able to begin upstreaming soon. Signed-off-by: Paul Burton <paul.burton@imgtec.com> Acked-by: Stefan Roese <sr@denx.de>
2013-09-04 14:16:56 +00:00
if (unlikely(mtd_is_eccerr(res)))
mtd->ecc_stats.failed +=
part->master->ecc_stats.failed - stats.failed;
else
mtd->ecc_stats.corrected +=
part->master->ecc_stats.corrected - stats.corrected;
return res;
}
#ifndef __UBOOT__
static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, void **virt, resource_size_t *phys)
{
struct mtd_part *part = PART(mtd);
return part->master->_point(part->master, from + part->offset, len,
retlen, virt, phys);
}
static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->_unpoint(part->master, from + part->offset, len);
}
#endif
static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
unsigned long len,
unsigned long offset,
unsigned long flags)
{
struct mtd_part *part = PART(mtd);
offset += part->offset;
return part->master->_get_unmapped_area(part->master, len, offset,
flags);
}
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;
/*
* If OOB is also requested, make sure that we do not read past the end
* of this partition.
*/
if (ops->oobbuf) {
size_t len, pages;
if (ops->mode == MTD_OPS_AUTO_OOB)
len = mtd->oobavail;
else
len = mtd->oobsize;
pages = mtd_div_by_ws(mtd->size, mtd);
pages -= mtd_div_by_ws(from, mtd);
if (ops->ooboffs + ops->ooblen > pages * len)
return -EINVAL;
}
res = part->master->_read_oob(part->master, from + part->offset, ops);
if (unlikely(res)) {
if (mtd_is_bitflip(res))
mtd->ecc_stats.corrected++;
if (mtd_is_eccerr(res))
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, size_t len,
size_t *retlen, struct otp_info *buf)
{
struct mtd_part *part = PART(mtd);
return part->master->_get_user_prot_info(part->master, len, retlen,
buf);
}
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, size_t len,
size_t *retlen, struct otp_info *buf)
{
struct mtd_part *part = PART(mtd);
return part->master->_get_fact_prot_info(part->master, len, retlen,
buf);
}
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);
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);
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 (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);
}
#ifndef __UBOOT__
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);
return part->master->_writev(part->master, vecs, count,
to + part->offset, retlen);
}
#endif
static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
{
struct mtd_part *part = PART(mtd);
int ret;
instr->addr += part->offset;
ret = part->master->_erase(part->master, instr);
if (ret) {
if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
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 != MTD_FAIL_ADDR_UNKNOWN)
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, uint64_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->_lock(part->master, ofs + part->offset, len);
}
static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->_unlock(part->master, ofs + part->offset, len);
}
static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
struct mtd_part *part = PART(mtd);
return part->master->_is_locked(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);
}
#ifndef __UBOOT__
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);
}
#endif
static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
{
struct mtd_part *part = PART(mtd);
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;
ofs += part->offset;
res = part->master->_block_markbad(part->master, ofs);
if (!res)
mtd->ecc_stats.badblocks++;
return res;
}
static inline void free_partition(struct mtd_part *p)
{
kfree(p->mtd.name);
kfree(p);
}
/*
* 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 mtd_part *slave, *next;
int ret, err = 0;
mutex_lock(&mtd_partitions_mutex);
list_for_each_entry_safe(slave, next, &mtd_partitions, list)
if (slave->master == master) {
ret = del_mtd_device(&slave->mtd);
if (ret < 0) {
err = ret;
continue;
}
list_del(&slave->list);
free_partition(slave);
}
mutex_unlock(&mtd_partitions_mutex);
return err;
}
static struct mtd_part *allocate_partition(struct mtd_info *master,
const struct mtd_partition *part, int partno,
uint64_t cur_offset)
{
struct mtd_part *slave;
char *name;
/* allocate the partition structure */
slave = kzalloc(sizeof(*slave), GFP_KERNEL);
name = kstrdup(part->name, GFP_KERNEL);
if (!name || !slave) {
printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
master->name);
kfree(name);
kfree(slave);
return ERR_PTR(-ENOMEM);
}
/* set up the MTD object for this partition */
slave->mtd.type = master->type;
slave->mtd.flags = master->flags & ~part->mask_flags;
slave->mtd.size = part->size;
slave->mtd.writesize = master->writesize;
slave->mtd.writebufsize = master->writebufsize;
slave->mtd.oobsize = master->oobsize;
slave->mtd.oobavail = master->oobavail;
slave->mtd.subpage_sft = master->subpage_sft;
slave->mtd.name = name;
slave->mtd.owner = master->owner;
#ifndef __UBOOT__
slave->mtd.backing_dev_info = master->backing_dev_info;
/* NOTE: we don't arrange MTDs as a tree; it'd be error-prone
* to have the same data be in two different partitions.
*/
slave->mtd.dev.parent = master->dev.parent;
#endif
slave->mtd._read = part_read;
slave->mtd._write = part_write;
if (master->_panic_write)
slave->mtd._panic_write = part_panic_write;
#ifndef __UBOOT__
if (master->_point && master->_unpoint) {
slave->mtd._point = part_point;
slave->mtd._unpoint = part_unpoint;
}
#endif
if (master->_get_unmapped_area)
slave->mtd._get_unmapped_area = part_get_unmapped_area;
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;
#ifndef __UBOOT__
if (!partno && !master->dev.class && master->_suspend &&
master->_resume) {
slave->mtd._suspend = part_suspend;
slave->mtd._resume = part_resume;
}
if (master->_writev)
slave->mtd._writev = part_writev;
#endif
if (master->_lock)
slave->mtd._lock = part_lock;
if (master->_unlock)
slave->mtd._unlock = part_unlock;
if (master->_is_locked)
slave->mtd._is_locked = part_is_locked;
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 = part->offset;
if (slave->offset == MTDPART_OFS_APPEND)
slave->offset = cur_offset;
if (slave->offset == MTDPART_OFS_NXTBLK) {
slave->offset = cur_offset;
if (mtd_mod_by_eb(cur_offset, master) != 0) {
/* Round up to next erasesize */
slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
debug("Moving partition %d: "
"0x%012llx -> 0x%012llx\n", partno,
(unsigned long long)cur_offset, (unsigned long long)slave->offset);
}
}
if (slave->offset == MTDPART_OFS_RETAIN) {
slave->offset = cur_offset;
if (master->size - slave->offset >= slave->mtd.size) {
slave->mtd.size = master->size - slave->offset
- slave->mtd.size;
} else {
debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
part->name, master->size - slave->offset,
slave->mtd.size);
/* register to preserve ordering */
goto out_register;
}
}
if (slave->mtd.size == MTDPART_SIZ_FULL)
slave->mtd.size = master->size - slave->offset;
debug("0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
(unsigned long long)(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(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
part->name);
goto out_register;
}
if (slave->offset + slave->mtd.size > master->size) {
slave->mtd.size = master->size - slave->offset;
printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
part->name, master->name, (unsigned long long)slave->mtd.size);
}
if (master->numeraseregions > 1) {
/* Deal with variable erase size stuff */
int i, max = master->numeraseregions;
u64 end = slave->offset + slave->mtd.size;
struct mtd_erase_region_info *regions = master->eraseregions;
/* Find the first erase regions which is part of this
* partition. */
for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
;
/* The loop searched for the region _behind_ the first one */
if (i > 0)
i--;
/* Pick biggest erasesize */
for (; i < max && regions[i].offset < end; i++) {
if (slave->mtd.erasesize < regions[i].erasesize) {
slave->mtd.erasesize = regions[i].erasesize;
}
}
BUG_ON(slave->mtd.erasesize == 0);
} else {
/* Single erase size */
slave->mtd.erasesize = master->erasesize;
}
if ((slave->mtd.flags & MTD_WRITEABLE) &&
mtd_mod_by_eb(slave->offset, &slave->mtd)) {
/* 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(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
part->name);
}
if ((slave->mtd.flags & MTD_WRITEABLE) &&
mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
slave->mtd.flags &= ~MTD_WRITEABLE;
printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
part->name);
}
slave->mtd.ecclayout = master->ecclayout;
slave->mtd.ecc_step_size = master->ecc_step_size;
slave->mtd.ecc_strength = master->ecc_strength;
slave->mtd.bitflip_threshold = master->bitflip_threshold;
if (master->_block_isbad) {
uint64_t offs = 0;
while (offs < slave->mtd.size) {
if (mtd_block_isbad(master, offs + slave->offset))
slave->mtd.ecc_stats.badblocks++;
offs += slave->mtd.erasesize;
}
}
out_register:
return slave;
}
#ifndef __UBOOT__
int mtd_add_partition(struct mtd_info *master, const char *name,
long long offset, long long length)
{
struct mtd_partition part;
struct mtd_part *p, *new;
uint64_t start, end;
int ret = 0;
/* the direct offset is expected */
if (offset == MTDPART_OFS_APPEND ||
offset == MTDPART_OFS_NXTBLK)
return -EINVAL;
if (length == MTDPART_SIZ_FULL)
length = master->size - offset;
if (length <= 0)
return -EINVAL;
part.name = name;
part.size = length;
part.offset = offset;
part.mask_flags = 0;
part.ecclayout = NULL;
new = allocate_partition(master, &part, -1, offset);
if (IS_ERR(new))
return PTR_ERR(new);
start = offset;
end = offset + length;
mutex_lock(&mtd_partitions_mutex);
list_for_each_entry(p, &mtd_partitions, list)
if (p->master == master) {
if ((start >= p->offset) &&
(start < (p->offset + p->mtd.size)))
goto err_inv;
if ((end >= p->offset) &&
(end < (p->offset + p->mtd.size)))
goto err_inv;
}
list_add(&new->list, &mtd_partitions);
mutex_unlock(&mtd_partitions_mutex);
add_mtd_device(&new->mtd);
return ret;
err_inv:
mutex_unlock(&mtd_partitions_mutex);
free_partition(new);
return -EINVAL;
}
EXPORT_SYMBOL_GPL(mtd_add_partition);
int mtd_del_partition(struct mtd_info *master, int partno)
{
struct mtd_part *slave, *next;
int ret = -EINVAL;
mutex_lock(&mtd_partitions_mutex);
list_for_each_entry_safe(slave, next, &mtd_partitions, list)
if ((slave->master == master) &&
(slave->mtd.index == partno)) {
ret = del_mtd_device(&slave->mtd);
if (ret < 0)
break;
list_del(&slave->list);
free_partition(slave);
break;
}
mutex_unlock(&mtd_partitions_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(mtd_del_partition);
#endif
/*
* 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.
*
* We don't register the master, or expect the caller to have done so,
* for reasons of data integrity.
*/
int add_mtd_partitions(struct mtd_info *master,
const struct mtd_partition *parts,
int nbparts)
{
struct mtd_part *slave;
uint64_t cur_offset = 0;
int i;
#ifdef __UBOOT__
/*
* Need to init the list here, since LIST_INIT() does not
* work on platforms where relocation has problems (like MIPS
* & PPC).
*/
if (mtd_partitions.next == NULL)
INIT_LIST_HEAD(&mtd_partitions);
#endif
debug("Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
for (i = 0; i < nbparts; i++) {
slave = allocate_partition(master, parts + i, i, cur_offset);
if (IS_ERR(slave))
return PTR_ERR(slave);
mutex_lock(&mtd_partitions_mutex);
list_add(&slave->list, &mtd_partitions);
mutex_unlock(&mtd_partitions_mutex);
add_mtd_device(&slave->mtd);
cur_offset = slave->offset + slave->mtd.size;
}
return 0;
}
#ifndef __UBOOT__
static DEFINE_SPINLOCK(part_parser_lock);
static LIST_HEAD(part_parsers);
static struct mtd_part_parser *get_partition_parser(const char *name)
{
struct mtd_part_parser *p, *ret = NULL;
spin_lock(&part_parser_lock);
list_for_each_entry(p, &part_parsers, list)
if (!strcmp(p->name, name) && try_module_get(p->owner)) {
ret = p;
break;
}
spin_unlock(&part_parser_lock);
return ret;
}
#define put_partition_parser(p) do { module_put((p)->owner); } while (0)
void register_mtd_parser(struct mtd_part_parser *p)
{
spin_lock(&part_parser_lock);
list_add(&p->list, &part_parsers);
spin_unlock(&part_parser_lock);
}
EXPORT_SYMBOL_GPL(register_mtd_parser);
void deregister_mtd_parser(struct mtd_part_parser *p)
{
spin_lock(&part_parser_lock);
list_del(&p->list);
spin_unlock(&part_parser_lock);
}
EXPORT_SYMBOL_GPL(deregister_mtd_parser);
/*
* Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
* are changing this array!
*/
static const char * const default_mtd_part_types[] = {
"cmdlinepart",
"ofpart",
NULL
};
/**
* parse_mtd_partitions - parse MTD partitions
* @master: the master partition (describes whole MTD device)
* @types: names of partition parsers to try or %NULL
* @pparts: array of partitions found is returned here
* @data: MTD partition parser-specific data
*
* This function tries to find partition on MTD device @master. It uses MTD
* partition parsers, specified in @types. However, if @types is %NULL, then
* the default list of parsers is used. The default list contains only the
* "cmdlinepart" and "ofpart" parsers ATM.
* Note: If there are more then one parser in @types, the kernel only takes the
* partitions parsed out by the first parser.
*
* This function may return:
* o a negative error code in case of failure
* o zero if no partitions were found
* o a positive number of found partitions, in which case on exit @pparts will
* point to an array containing this number of &struct mtd_info objects.
*/
int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
struct mtd_partition **pparts,
struct mtd_part_parser_data *data)
{
struct mtd_part_parser *parser;
int ret = 0;
if (!types)
types = default_mtd_part_types;
for ( ; ret <= 0 && *types; types++) {
parser = get_partition_parser(*types);
if (!parser && !request_module("%s", *types))
parser = get_partition_parser(*types);
if (!parser)
continue;
ret = (*parser->parse_fn)(master, pparts, data);
put_partition_parser(parser);
if (ret > 0) {
printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
ret, parser->name, master->name);
break;
}
}
return ret;
}
#endif
int mtd_is_partition(const struct mtd_info *mtd)
{
struct mtd_part *part;
int ispart = 0;
mutex_lock(&mtd_partitions_mutex);
list_for_each_entry(part, &mtd_partitions, list)
if (&part->mtd == mtd) {
ispart = 1;
break;
}
mutex_unlock(&mtd_partitions_mutex);
return ispart;
}
EXPORT_SYMBOL_GPL(mtd_is_partition);
/* Returns the size of the entire flash chip */
uint64_t mtd_get_device_size(const struct mtd_info *mtd)
{
if (!mtd_is_partition(mtd))
return mtd->size;
return PART(mtd)->master->size;
}
EXPORT_SYMBOL_GPL(mtd_get_device_size);