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u-boot/drivers/mtd/mtdcore.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style 
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

1738 lines
44 KiB
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// SPDX-License-Identifier: GPL-2.0+
/*
* Core registration and callback routines for MTD
* drivers and users.
*
* Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
* Copyright © 2006 Red Hat UK Limited
*
*/
#ifndef __UBOOT__
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/err.h>
#include <linux/ioctl.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/idr.h>
#include <linux/backing-dev.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#else
#include <linux/err.h>
#include <ubi_uboot.h>
#endif
#include <linux/log2.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include "mtdcore.h"
#ifndef __UBOOT__
/*
* backing device capabilities for non-mappable devices (such as NAND flash)
* - permits private mappings, copies are taken of the data
*/
static struct backing_dev_info mtd_bdi_unmappable = {
.capabilities = BDI_CAP_MAP_COPY,
};
/*
* backing device capabilities for R/O mappable devices (such as ROM)
* - permits private mappings, copies are taken of the data
* - permits non-writable shared mappings
*/
static struct backing_dev_info mtd_bdi_ro_mappable = {
.capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
};
/*
* backing device capabilities for writable mappable devices (such as RAM)
* - permits private mappings, copies are taken of the data
* - permits non-writable shared mappings
*/
static struct backing_dev_info mtd_bdi_rw_mappable = {
.capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
BDI_CAP_WRITE_MAP),
};
static int mtd_cls_suspend(struct device *dev, pm_message_t state);
static int mtd_cls_resume(struct device *dev);
static struct class mtd_class = {
.name = "mtd",
.owner = THIS_MODULE,
.suspend = mtd_cls_suspend,
.resume = mtd_cls_resume,
};
#else
struct mtd_info *mtd_table[MAX_MTD_DEVICES];
#define MAX_IDR_ID 64
struct idr_layer {
int used;
void *ptr;
};
struct idr {
struct idr_layer id[MAX_IDR_ID];
};
#define DEFINE_IDR(name) struct idr name;
void idr_remove(struct idr *idp, int id)
{
if (idp->id[id].used)
idp->id[id].used = 0;
return;
}
void *idr_find(struct idr *idp, int id)
{
if (idp->id[id].used)
return idp->id[id].ptr;
return NULL;
}
void *idr_get_next(struct idr *idp, int *next)
{
void *ret;
int id = *next;
ret = idr_find(idp, id);
if (ret) {
id ++;
if (!idp->id[id].used)
id = 0;
*next = id;
} else {
*next = 0;
}
return ret;
}
int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
{
struct idr_layer *idl;
int i = 0;
while (i < MAX_IDR_ID) {
idl = &idp->id[i];
if (idl->used == 0) {
idl->used = 1;
idl->ptr = ptr;
return i;
}
i++;
}
return -ENOSPC;
}
#endif
static DEFINE_IDR(mtd_idr);
/* These are exported solely for the purpose of mtd_blkdevs.c. You
should not use them for _anything_ else */
DEFINE_MUTEX(mtd_table_mutex);
EXPORT_SYMBOL_GPL(mtd_table_mutex);
struct mtd_info *__mtd_next_device(int i)
{
return idr_get_next(&mtd_idr, &i);
}
EXPORT_SYMBOL_GPL(__mtd_next_device);
#ifndef __UBOOT__
static LIST_HEAD(mtd_notifiers);
#define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
/* REVISIT once MTD uses the driver model better, whoever allocates
* the mtd_info will probably want to use the release() hook...
*/
static void mtd_release(struct device *dev)
{
struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
dev_t index = MTD_DEVT(mtd->index);
/* remove /dev/mtdXro node if needed */
if (index)
device_destroy(&mtd_class, index + 1);
}
static int mtd_cls_suspend(struct device *dev, pm_message_t state)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return mtd ? mtd_suspend(mtd) : 0;
}
static int mtd_cls_resume(struct device *dev)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
if (mtd)
mtd_resume(mtd);
return 0;
}
static ssize_t mtd_type_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
char *type;
switch (mtd->type) {
case MTD_ABSENT:
type = "absent";
break;
case MTD_RAM:
type = "ram";
break;
case MTD_ROM:
type = "rom";
break;
case MTD_NORFLASH:
type = "nor";
break;
case MTD_NANDFLASH:
type = "nand";
break;
case MTD_DATAFLASH:
type = "dataflash";
break;
case MTD_UBIVOLUME:
type = "ubi";
break;
case MTD_MLCNANDFLASH:
type = "mlc-nand";
break;
default:
type = "unknown";
}
return snprintf(buf, PAGE_SIZE, "%s\n", type);
}
static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
static ssize_t mtd_flags_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
}
static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
static ssize_t mtd_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%llu\n",
(unsigned long long)mtd->size);
}
static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
static ssize_t mtd_erasesize_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
}
static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
static ssize_t mtd_writesize_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
}
static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
static ssize_t mtd_subpagesize_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
}
static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
static ssize_t mtd_oobsize_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
}
static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
static ssize_t mtd_numeraseregions_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
}
static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
NULL);
static ssize_t mtd_name_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
}
static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
static ssize_t mtd_ecc_strength_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
}
static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
static ssize_t mtd_bitflip_threshold_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
}
static ssize_t mtd_bitflip_threshold_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
unsigned int bitflip_threshold;
int retval;
retval = kstrtouint(buf, 0, &bitflip_threshold);
if (retval)
return retval;
mtd->bitflip_threshold = bitflip_threshold;
return count;
}
static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
mtd_bitflip_threshold_show,
mtd_bitflip_threshold_store);
static ssize_t mtd_ecc_step_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct mtd_info *mtd = dev_get_drvdata(dev);
return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_step_size);
}
static DEVICE_ATTR(ecc_step_size, S_IRUGO, mtd_ecc_step_size_show, NULL);
static struct attribute *mtd_attrs[] = {
&dev_attr_type.attr,
&dev_attr_flags.attr,
&dev_attr_size.attr,
&dev_attr_erasesize.attr,
&dev_attr_writesize.attr,
&dev_attr_subpagesize.attr,
&dev_attr_oobsize.attr,
&dev_attr_numeraseregions.attr,
&dev_attr_name.attr,
&dev_attr_ecc_strength.attr,
&dev_attr_ecc_step_size.attr,
&dev_attr_bitflip_threshold.attr,
NULL,
};
ATTRIBUTE_GROUPS(mtd);
static struct device_type mtd_devtype = {
.name = "mtd",
.groups = mtd_groups,
.release = mtd_release,
};
#endif
/**
* add_mtd_device - register an MTD device
* @mtd: pointer to new MTD device info structure
*
* Add a device to the list of MTD devices present in the system, and
* notify each currently active MTD 'user' of its arrival. Returns
* zero on success or 1 on failure, which currently will only happen
* if there is insufficient memory or a sysfs error.
*/
int add_mtd_device(struct mtd_info *mtd)
{
#ifndef __UBOOT__
struct mtd_notifier *not;
#endif
int i, error;
#ifndef __UBOOT__
if (!mtd->backing_dev_info) {
switch (mtd->type) {
case MTD_RAM:
mtd->backing_dev_info = &mtd_bdi_rw_mappable;
break;
case MTD_ROM:
mtd->backing_dev_info = &mtd_bdi_ro_mappable;
break;
default:
mtd->backing_dev_info = &mtd_bdi_unmappable;
break;
}
}
#endif
BUG_ON(mtd->writesize == 0);
mutex_lock(&mtd_table_mutex);
i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
if (i < 0)
goto fail_locked;
mtd->index = i;
mtd->usecount = 0;
/* default value if not set by driver */
if (mtd->bitflip_threshold == 0)
mtd->bitflip_threshold = mtd->ecc_strength;
if (is_power_of_2(mtd->erasesize))
mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
else
mtd->erasesize_shift = 0;
if (is_power_of_2(mtd->writesize))
mtd->writesize_shift = ffs(mtd->writesize) - 1;
else
mtd->writesize_shift = 0;
mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
/* Some chips always power up locked. Unlock them now */
if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
error = mtd_unlock(mtd, 0, mtd->size);
if (error && error != -EOPNOTSUPP)
printk(KERN_WARNING
"%s: unlock failed, writes may not work\n",
mtd->name);
}
#ifndef __UBOOT__
/* Caller should have set dev.parent to match the
* physical device.
*/
mtd->dev.type = &mtd_devtype;
mtd->dev.class = &mtd_class;
mtd->dev.devt = MTD_DEVT(i);
dev_set_name(&mtd->dev, "mtd%d", i);
dev_set_drvdata(&mtd->dev, mtd);
if (device_register(&mtd->dev) != 0)
goto fail_added;
if (MTD_DEVT(i))
device_create(&mtd_class, mtd->dev.parent,
MTD_DEVT(i) + 1,
NULL, "mtd%dro", i);
pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
/* No need to get a refcount on the module containing
the notifier, since we hold the mtd_table_mutex */
list_for_each_entry(not, &mtd_notifiers, list)
not->add(mtd);
#else
pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
#endif
mutex_unlock(&mtd_table_mutex);
/* We _know_ we aren't being removed, because
our caller is still holding us here. So none
of this try_ nonsense, and no bitching about it
either. :) */
__module_get(THIS_MODULE);
return 0;
#ifndef __UBOOT__
fail_added:
idr_remove(&mtd_idr, i);
#endif
fail_locked:
mutex_unlock(&mtd_table_mutex);
return 1;
}
/**
* del_mtd_device - unregister an MTD device
* @mtd: pointer to MTD device info structure
*
* Remove a device from the list of MTD devices present in the system,
* and notify each currently active MTD 'user' of its departure.
* Returns zero on success or 1 on failure, which currently will happen
* if the requested device does not appear to be present in the list.
*/
int del_mtd_device(struct mtd_info *mtd)
{
int ret;
#ifndef __UBOOT__
struct mtd_notifier *not;
#endif
mutex_lock(&mtd_table_mutex);
if (idr_find(&mtd_idr, mtd->index) != mtd) {
ret = -ENODEV;
goto out_error;
}
#ifndef __UBOOT__
/* No need to get a refcount on the module containing
the notifier, since we hold the mtd_table_mutex */
list_for_each_entry(not, &mtd_notifiers, list)
not->remove(mtd);
#endif
if (mtd->usecount) {
printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
mtd->index, mtd->name, mtd->usecount);
ret = -EBUSY;
} else {
#ifndef __UBOOT__
device_unregister(&mtd->dev);
#endif
idr_remove(&mtd_idr, mtd->index);
module_put(THIS_MODULE);
ret = 0;
}
out_error:
mutex_unlock(&mtd_table_mutex);
return ret;
}
#ifndef __UBOOT__
/**
* mtd_device_parse_register - parse partitions and register an MTD device.
*
* @mtd: the MTD device to register
* @types: the list of MTD partition probes to try, see
* 'parse_mtd_partitions()' for more information
* @parser_data: MTD partition parser-specific data
* @parts: fallback partition information to register, if parsing fails;
* only valid if %nr_parts > %0
* @nr_parts: the number of partitions in parts, if zero then the full
* MTD device is registered if no partition info is found
*
* This function aggregates MTD partitions parsing (done by
* 'parse_mtd_partitions()') and MTD device and partitions registering. It
* basically follows the most common pattern found in many MTD drivers:
*
* * It first tries to probe partitions on MTD device @mtd using parsers
* specified in @types (if @types is %NULL, then the default list of parsers
* is used, see 'parse_mtd_partitions()' for more information). If none are
* found this functions tries to fallback to information specified in
* @parts/@nr_parts.
* * If any partitioning info was found, this function registers the found
* partitions.
* * If no partitions were found this function just registers the MTD device
* @mtd and exits.
*
* Returns zero in case of success and a negative error code in case of failure.
*/
int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
struct mtd_part_parser_data *parser_data,
const struct mtd_partition *parts,
int nr_parts)
{
int err;
struct mtd_partition *real_parts;
err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
if (err <= 0 && nr_parts && parts) {
real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
GFP_KERNEL);
if (!real_parts)
err = -ENOMEM;
else
err = nr_parts;
}
if (err > 0) {
err = add_mtd_partitions(mtd, real_parts, err);
kfree(real_parts);
} else if (err == 0) {
err = add_mtd_device(mtd);
if (err == 1)
err = -ENODEV;
}
return err;
}
EXPORT_SYMBOL_GPL(mtd_device_parse_register);
/**
* mtd_device_unregister - unregister an existing MTD device.
*
* @master: the MTD device to unregister. This will unregister both the master
* and any partitions if registered.
*/
int mtd_device_unregister(struct mtd_info *master)
{
int err;
err = del_mtd_partitions(master);
if (err)
return err;
if (!device_is_registered(&master->dev))
return 0;
return del_mtd_device(master);
}
EXPORT_SYMBOL_GPL(mtd_device_unregister);
/**
* register_mtd_user - register a 'user' of MTD devices.
* @new: pointer to notifier info structure
*
* Registers a pair of callbacks function to be called upon addition
* or removal of MTD devices. Causes the 'add' callback to be immediately
* invoked for each MTD device currently present in the system.
*/
void register_mtd_user (struct mtd_notifier *new)
{
struct mtd_info *mtd;
mutex_lock(&mtd_table_mutex);
list_add(&new->list, &mtd_notifiers);
__module_get(THIS_MODULE);
mtd_for_each_device(mtd)
new->add(mtd);
mutex_unlock(&mtd_table_mutex);
}
EXPORT_SYMBOL_GPL(register_mtd_user);
/**
* unregister_mtd_user - unregister a 'user' of MTD devices.
* @old: pointer to notifier info structure
*
* Removes a callback function pair from the list of 'users' to be
* notified upon addition or removal of MTD devices. Causes the
* 'remove' callback to be immediately invoked for each MTD device
* currently present in the system.
*/
int unregister_mtd_user (struct mtd_notifier *old)
{
struct mtd_info *mtd;
mutex_lock(&mtd_table_mutex);
module_put(THIS_MODULE);
mtd_for_each_device(mtd)
old->remove(mtd);
list_del(&old->list);
mutex_unlock(&mtd_table_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(unregister_mtd_user);
#endif
/**
* get_mtd_device - obtain a validated handle for an MTD device
* @mtd: last known address of the required MTD device
* @num: internal device number of the required MTD device
*
* Given a number and NULL address, return the num'th entry in the device
* table, if any. Given an address and num == -1, search the device table
* for a device with that address and return if it's still present. Given
* both, return the num'th driver only if its address matches. Return
* error code if not.
*/
struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
{
struct mtd_info *ret = NULL, *other;
int err = -ENODEV;
mutex_lock(&mtd_table_mutex);
if (num == -1) {
mtd_for_each_device(other) {
if (other == mtd) {
ret = mtd;
break;
}
}
} else if (num >= 0) {
ret = idr_find(&mtd_idr, num);
if (mtd && mtd != ret)
ret = NULL;
}
if (!ret) {
ret = ERR_PTR(err);
goto out;
}
err = __get_mtd_device(ret);
if (err)
ret = ERR_PTR(err);
out:
mutex_unlock(&mtd_table_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(get_mtd_device);
int __get_mtd_device(struct mtd_info *mtd)
{
int err;
if (!try_module_get(mtd->owner))
return -ENODEV;
if (mtd->_get_device) {
err = mtd->_get_device(mtd);
if (err) {
module_put(mtd->owner);
return err;
}
}
mtd->usecount++;
return 0;
}
EXPORT_SYMBOL_GPL(__get_mtd_device);
/**
* get_mtd_device_nm - obtain a validated handle for an MTD device by
* device name
* @name: MTD device name to open
*
* This function returns MTD device description structure in case of
* success and an error code in case of failure.
*/
struct mtd_info *get_mtd_device_nm(const char *name)
{
int err = -ENODEV;
struct mtd_info *mtd = NULL, *other;
mutex_lock(&mtd_table_mutex);
mtd_for_each_device(other) {
if (!strcmp(name, other->name)) {
mtd = other;
break;
}
}
if (!mtd)
goto out_unlock;
err = __get_mtd_device(mtd);
if (err)
goto out_unlock;
mutex_unlock(&mtd_table_mutex);
return mtd;
out_unlock:
mutex_unlock(&mtd_table_mutex);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(get_mtd_device_nm);
#if defined(CONFIG_CMD_MTDPARTS_SPREAD)
/**
* mtd_get_len_incl_bad
*
* Check if length including bad blocks fits into device.
*
* @param mtd an MTD device
* @param offset offset in flash
* @param length image length
* @return image length including bad blocks in *len_incl_bad and whether or not
* the length returned was truncated in *truncated
*/
void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset,
const uint64_t length, uint64_t *len_incl_bad,
int *truncated)
{
*truncated = 0;
*len_incl_bad = 0;
if (!mtd->_block_isbad) {
*len_incl_bad = length;
return;
}
uint64_t len_excl_bad = 0;
uint64_t block_len;
while (len_excl_bad < length) {
if (offset >= mtd->size) {
*truncated = 1;
return;
}
block_len = mtd->erasesize - (offset & (mtd->erasesize - 1));
if (!mtd->_block_isbad(mtd, offset & ~(mtd->erasesize - 1)))
len_excl_bad += block_len;
*len_incl_bad += block_len;
offset += block_len;
}
}
#endif /* defined(CONFIG_CMD_MTDPARTS_SPREAD) */
void put_mtd_device(struct mtd_info *mtd)
{
mutex_lock(&mtd_table_mutex);
__put_mtd_device(mtd);
mutex_unlock(&mtd_table_mutex);
}
EXPORT_SYMBOL_GPL(put_mtd_device);
void __put_mtd_device(struct mtd_info *mtd)
{
--mtd->usecount;
BUG_ON(mtd->usecount < 0);
if (mtd->_put_device)
mtd->_put_device(mtd);
module_put(mtd->owner);
}
EXPORT_SYMBOL_GPL(__put_mtd_device);
/*
* Erase is an asynchronous operation. Device drivers are supposed
* to call instr->callback() whenever the operation completes, even
* if it completes with a failure.
* Callers are supposed to pass a callback function and wait for it
* to be called before writing to the block.
*/
int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
{
if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
if (!instr->len) {
instr->state = MTD_ERASE_DONE;
mtd_erase_callback(instr);
return 0;
}
return mtd->_erase(mtd, instr);
}
EXPORT_SYMBOL_GPL(mtd_erase);
#ifndef __UBOOT__
/*
* This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
*/
int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
void **virt, resource_size_t *phys)
{
*retlen = 0;
*virt = NULL;
if (phys)
*phys = 0;
if (!mtd->_point)
return -EOPNOTSUPP;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
if (!len)
return 0;
return mtd->_point(mtd, from, len, retlen, virt, phys);
}
EXPORT_SYMBOL_GPL(mtd_point);
/* We probably shouldn't allow XIP if the unpoint isn't a NULL */
int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
{
if (!mtd->_point)
return -EOPNOTSUPP;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
if (!len)
return 0;
return mtd->_unpoint(mtd, from, len);
}
EXPORT_SYMBOL_GPL(mtd_unpoint);
#endif
/*
* Allow NOMMU mmap() to directly map the device (if not NULL)
* - return the address to which the offset maps
* - return -ENOSYS to indicate refusal to do the mapping
*/
unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
unsigned long offset, unsigned long flags)
{
if (!mtd->_get_unmapped_area)
return -EOPNOTSUPP;
if (offset > mtd->size || len > mtd->size - offset)
return -EINVAL;
return mtd->_get_unmapped_area(mtd, len, offset, flags);
}
EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
u_char *buf)
{
int ret_code;
*retlen = 0;
if (from < 0 || from > mtd->size || len > mtd->size - from)
return -EINVAL;
if (!len)
return 0;
/*
* In the absence of an error, drivers return a non-negative integer
* representing the maximum number of bitflips that were corrected on
* any one ecc region (if applicable; zero otherwise).
*/
ret_code = mtd->_read(mtd, from, len, retlen, buf);
if (unlikely(ret_code < 0))
return ret_code;
if (mtd->ecc_strength == 0)
return 0; /* device lacks ecc */
return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
}
EXPORT_SYMBOL_GPL(mtd_read);
int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
const u_char *buf)
{
*retlen = 0;
if (to < 0 || to > mtd->size || len > mtd->size - to)
return -EINVAL;
if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!len)
return 0;
return mtd->_write(mtd, to, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_write);
/*
* In blackbox flight recorder like scenarios we want to make successful writes
* in interrupt context. panic_write() is only intended to be called when its
* known the kernel is about to panic and we need the 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).
*/
int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
const u_char *buf)
{
*retlen = 0;
if (!mtd->_panic_write)
return -EOPNOTSUPP;
if (to < 0 || to > mtd->size || len > mtd->size - to)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!len)
return 0;
return mtd->_panic_write(mtd, to, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_panic_write);
int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
{
int ret_code;
ops->retlen = ops->oobretlen = 0;
if (!mtd->_read_oob)
return -EOPNOTSUPP;
/*
* In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
* similar to mtd->_read(), returning a non-negative integer
* representing max bitflips. In other cases, mtd->_read_oob() may
* return -EUCLEAN. In all cases, perform similar logic to mtd_read().
*/
ret_code = mtd->_read_oob(mtd, from, ops);
if (unlikely(ret_code < 0))
return ret_code;
if (mtd->ecc_strength == 0)
return 0; /* device lacks ecc */
return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
}
EXPORT_SYMBOL_GPL(mtd_read_oob);
/**
* mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section
* @mtd: MTD device structure
* @section: ECC section. Depending on the layout you may have all the ECC
* bytes stored in a single contiguous section, or one section
* per ECC chunk (and sometime several sections for a single ECC
* ECC chunk)
* @oobecc: OOB region struct filled with the appropriate ECC position
* information
*
* This function returns ECC section information in the OOB area. If you want
* to get all the ECC bytes information, then you should call
* mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobecc)
{
memset(oobecc, 0, sizeof(*oobecc));
if (!mtd || section < 0)
return -EINVAL;
if (!mtd->ooblayout || !mtd->ooblayout->ecc)
return -ENOTSUPP;
return mtd->ooblayout->ecc(mtd, section, oobecc);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc);
/**
* mtd_ooblayout_free - Get the OOB region definition of a specific free
* section
* @mtd: MTD device structure
* @section: Free section you are interested in. Depending on the layout
* you may have all the free bytes stored in a single contiguous
* section, or one section per ECC chunk plus an extra section
* for the remaining bytes (or other funky layout).
* @oobfree: OOB region struct filled with the appropriate free position
* information
*
* This function returns free bytes position in the OOB area. If you want
* to get all the free bytes information, then you should call
* mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_free(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobfree)
{
memset(oobfree, 0, sizeof(*oobfree));
if (!mtd || section < 0)
return -EINVAL;
if (!mtd->ooblayout || !mtd->ooblayout->free)
return -ENOTSUPP;
return mtd->ooblayout->free(mtd, section, oobfree);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_free);
/**
* mtd_ooblayout_find_region - Find the region attached to a specific byte
* @mtd: mtd info structure
* @byte: the byte we are searching for
* @sectionp: pointer where the section id will be stored
* @oobregion: used to retrieve the ECC position
* @iter: iterator function. Should be either mtd_ooblayout_free or
* mtd_ooblayout_ecc depending on the region type you're searching for
*
* This function returns the section id and oobregion information of a
* specific byte. For example, say you want to know where the 4th ECC byte is
* stored, you'll use:
*
* mtd_ooblayout_find_region(mtd, 3, &section, &oobregion, mtd_ooblayout_ecc);
*
* Returns zero on success, a negative error code otherwise.
*/
static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte,
int *sectionp, struct mtd_oob_region *oobregion,
int (*iter)(struct mtd_info *,
int section,
struct mtd_oob_region *oobregion))
{
int pos = 0, ret, section = 0;
memset(oobregion, 0, sizeof(*oobregion));
while (1) {
ret = iter(mtd, section, oobregion);
if (ret)
return ret;
if (pos + oobregion->length > byte)
break;
pos += oobregion->length;
section++;
}
/*
* Adjust region info to make it start at the beginning at the
* 'start' ECC byte.
*/
oobregion->offset += byte - pos;
oobregion->length -= byte - pos;
*sectionp = section;
return 0;
}
/**
* mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific
* ECC byte
* @mtd: mtd info structure
* @eccbyte: the byte we are searching for
* @sectionp: pointer where the section id will be stored
* @oobregion: OOB region information
*
* Works like mtd_ooblayout_find_region() except it searches for a specific ECC
* byte.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
int *section,
struct mtd_oob_region *oobregion)
{
return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion,
mtd_ooblayout_ecc);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion);
/**
* mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer
* @mtd: mtd info structure
* @buf: destination buffer to store OOB bytes
* @oobbuf: OOB buffer
* @start: first byte to retrieve
* @nbytes: number of bytes to retrieve
* @iter: section iterator
*
* Extract bytes attached to a specific category (ECC or free)
* from the OOB buffer and copy them into buf.
*
* Returns zero on success, a negative error code otherwise.
*/
static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf,
const u8 *oobbuf, int start, int nbytes,
int (*iter)(struct mtd_info *,
int section,
struct mtd_oob_region *oobregion))
{
struct mtd_oob_region oobregion;
int section, ret;
ret = mtd_ooblayout_find_region(mtd, start, &section,
&oobregion, iter);
while (!ret) {
int cnt;
cnt = min_t(int, nbytes, oobregion.length);
memcpy(buf, oobbuf + oobregion.offset, cnt);
buf += cnt;
nbytes -= cnt;
if (!nbytes)
break;
ret = iter(mtd, ++section, &oobregion);
}
return ret;
}
/**
* mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer
* @mtd: mtd info structure
* @buf: source buffer to get OOB bytes from
* @oobbuf: OOB buffer
* @start: first OOB byte to set
* @nbytes: number of OOB bytes to set
* @iter: section iterator
*
* Fill the OOB buffer with data provided in buf. The category (ECC or free)
* is selected by passing the appropriate iterator.
*
* Returns zero on success, a negative error code otherwise.
*/
static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf,
u8 *oobbuf, int start, int nbytes,
int (*iter)(struct mtd_info *,
int section,
struct mtd_oob_region *oobregion))
{
struct mtd_oob_region oobregion;
int section, ret;
ret = mtd_ooblayout_find_region(mtd, start, &section,
&oobregion, iter);
while (!ret) {
int cnt;
cnt = min_t(int, nbytes, oobregion.length);
memcpy(oobbuf + oobregion.offset, buf, cnt);
buf += cnt;
nbytes -= cnt;
if (!nbytes)
break;
ret = iter(mtd, ++section, &oobregion);
}
return ret;
}
/**
* mtd_ooblayout_count_bytes - count the number of bytes in a OOB category
* @mtd: mtd info structure
* @iter: category iterator
*
* Count the number of bytes in a given category.
*
* Returns a positive value on success, a negative error code otherwise.
*/
static int mtd_ooblayout_count_bytes(struct mtd_info *mtd,
int (*iter)(struct mtd_info *,
int section,
struct mtd_oob_region *oobregion))
{
struct mtd_oob_region oobregion;
int section = 0, ret, nbytes = 0;
while (1) {
ret = iter(mtd, section++, &oobregion);
if (ret) {
if (ret == -ERANGE)
ret = nbytes;
break;
}
nbytes += oobregion.length;
}
return ret;
}
/**
* mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer
* @mtd: mtd info structure
* @eccbuf: destination buffer to store ECC bytes
* @oobbuf: OOB buffer
* @start: first ECC byte to retrieve
* @nbytes: number of ECC bytes to retrieve
*
* Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
const u8 *oobbuf, int start, int nbytes)
{
return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes,
mtd_ooblayout_ecc);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes);
/**
* mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer
* @mtd: mtd info structure
* @eccbuf: source buffer to get ECC bytes from
* @oobbuf: OOB buffer
* @start: first ECC byte to set
* @nbytes: number of ECC bytes to set
*
* Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
u8 *oobbuf, int start, int nbytes)
{
return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes,
mtd_ooblayout_ecc);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes);
/**
* mtd_ooblayout_get_databytes - extract data bytes from the oob buffer
* @mtd: mtd info structure
* @databuf: destination buffer to store ECC bytes
* @oobbuf: OOB buffer
* @start: first ECC byte to retrieve
* @nbytes: number of ECC bytes to retrieve
*
* Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
const u8 *oobbuf, int start, int nbytes)
{
return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes,
mtd_ooblayout_free);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes);
/**
* mtd_ooblayout_get_eccbytes - set data bytes into the oob buffer
* @mtd: mtd info structure
* @eccbuf: source buffer to get data bytes from
* @oobbuf: OOB buffer
* @start: first ECC byte to set
* @nbytes: number of ECC bytes to set
*
* Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
u8 *oobbuf, int start, int nbytes)
{
return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes,
mtd_ooblayout_free);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes);
/**
* mtd_ooblayout_count_freebytes - count the number of free bytes in OOB
* @mtd: mtd info structure
*
* Works like mtd_ooblayout_count_bytes(), except it count free bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_count_freebytes(struct mtd_info *mtd)
{
return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes);
/**
* mtd_ooblayout_count_freebytes - count the number of ECC bytes in OOB
* @mtd: mtd info structure
*
* Works like mtd_ooblayout_count_bytes(), except it count ECC bytes.
*
* Returns zero on success, a negative error code otherwise.
*/
int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd)
{
return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc);
}
EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes);
/*
* Method to access the protection register area, present in some flash
* devices. The user data is one time programmable but the factory data is read
* only.
*/
int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
struct otp_info *buf)
{
if (!mtd->_get_fact_prot_info)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_get_fact_prot_info(mtd, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
*retlen = 0;
if (!mtd->_read_fact_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
struct otp_info *buf)
{
if (!mtd->_get_user_prot_info)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_get_user_prot_info(mtd, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
*retlen = 0;
if (!mtd->_read_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, u_char *buf)
{
int ret;
*retlen = 0;
if (!mtd->_write_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
ret = mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
if (ret)
return ret;
/*
* If no data could be written at all, we are out of memory and
* must return -ENOSPC.
*/
return (*retlen) ? 0 : -ENOSPC;
}
EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
{
if (!mtd->_lock_user_prot_reg)
return -EOPNOTSUPP;
if (!len)
return 0;
return mtd->_lock_user_prot_reg(mtd, from, len);
}
EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
/* Chip-supported device locking */
int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
if (!mtd->_lock)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
if (!len)
return 0;
return mtd->_lock(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_lock);
int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
if (!mtd->_unlock)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
if (!len)
return 0;
return mtd->_unlock(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_unlock);
int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
if (!mtd->_is_locked)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
return -EINVAL;
if (!len)
return 0;
return mtd->_is_locked(mtd, ofs, len);
}
EXPORT_SYMBOL_GPL(mtd_is_locked);
int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs)
{
if (ofs < 0 || ofs > mtd->size)
return -EINVAL;
if (!mtd->_block_isreserved)
return 0;
return mtd->_block_isreserved(mtd, ofs);
}
EXPORT_SYMBOL_GPL(mtd_block_isreserved);
int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
{
if (ofs < 0 || ofs > mtd->size)
return -EINVAL;
if (!mtd->_block_isbad)
return 0;
return mtd->_block_isbad(mtd, ofs);
}
EXPORT_SYMBOL_GPL(mtd_block_isbad);
int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
if (!mtd->_block_markbad)
return -EOPNOTSUPP;
if (ofs < 0 || ofs > mtd->size)
return -EINVAL;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
return mtd->_block_markbad(mtd, ofs);
}
EXPORT_SYMBOL_GPL(mtd_block_markbad);
#ifndef __UBOOT__
/*
* default_mtd_writev - the default writev method
* @mtd: mtd device description object pointer
* @vecs: the vectors to write
* @count: count of vectors in @vecs
* @to: the MTD device offset to write to
* @retlen: on exit contains the count of bytes written to the MTD device.
*
* This function returns zero in case of success and a negative error code in
* case of failure.
*/
static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen)
{
unsigned long i;
size_t totlen = 0, thislen;
int ret = 0;
for (i = 0; i < count; i++) {
if (!vecs[i].iov_len)
continue;
ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
vecs[i].iov_base);
totlen += thislen;
if (ret || thislen != vecs[i].iov_len)
break;
to += vecs[i].iov_len;
}
*retlen = totlen;
return ret;
}
/*
* mtd_writev - the vector-based MTD write method
* @mtd: mtd device description object pointer
* @vecs: the vectors to write
* @count: count of vectors in @vecs
* @to: the MTD device offset to write to
* @retlen: on exit contains the count of bytes written to the MTD device.
*
* This function returns zero in case of success and a negative error code in
* case of failure.
*/
int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
unsigned long count, loff_t to, size_t *retlen)
{
*retlen = 0;
if (!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!mtd->_writev)
return default_mtd_writev(mtd, vecs, count, to, retlen);
return mtd->_writev(mtd, vecs, count, to, retlen);
}
EXPORT_SYMBOL_GPL(mtd_writev);
/**
* mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
* @mtd: mtd device description object pointer
* @size: a pointer to the ideal or maximum size of the allocation, points
* to the actual allocation size on success.
*
* This routine attempts to allocate a contiguous kernel buffer up to
* the specified size, backing off the size of the request exponentially
* until the request succeeds or until the allocation size falls below
* the system page size. This attempts to make sure it does not adversely
* impact system performance, so when allocating more than one page, we
* ask the memory allocator to avoid re-trying, swapping, writing back
* or performing I/O.
*
* Note, this function also makes sure that the allocated buffer is aligned to
* the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
*
* This is called, for example by mtd_{read,write} and jffs2_scan_medium,
* to handle smaller (i.e. degraded) buffer allocations under low- or
* fragmented-memory situations where such reduced allocations, from a
* requested ideal, are allowed.
*
* Returns a pointer to the allocated buffer on success; otherwise, NULL.
*/
void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
{
gfp_t flags = __GFP_NOWARN | __GFP_WAIT |
__GFP_NORETRY | __GFP_NO_KSWAPD;
size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
void *kbuf;
*size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
while (*size > min_alloc) {
kbuf = kmalloc(*size, flags);
if (kbuf)
return kbuf;
*size >>= 1;
*size = ALIGN(*size, mtd->writesize);
}
/*
* For the last resort allocation allow 'kmalloc()' to do all sorts of
* things (write-back, dropping caches, etc) by using GFP_KERNEL.
*/
return kmalloc(*size, GFP_KERNEL);
}
EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
#endif
#ifdef CONFIG_PROC_FS
/*====================================================================*/
/* Support for /proc/mtd */
static int mtd_proc_show(struct seq_file *m, void *v)
{
struct mtd_info *mtd;
seq_puts(m, "dev: size erasesize name\n");
mutex_lock(&mtd_table_mutex);
mtd_for_each_device(mtd) {
seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
mtd->index, (unsigned long long)mtd->size,
mtd->erasesize, mtd->name);
}
mutex_unlock(&mtd_table_mutex);
return 0;
}
static int mtd_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, mtd_proc_show, NULL);
}
static const struct file_operations mtd_proc_ops = {
.open = mtd_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
#endif /* CONFIG_PROC_FS */
/*====================================================================*/
/* Init code */
#ifndef __UBOOT__
static int __init mtd_bdi_init(struct backing_dev_info *bdi, const char *name)
{
int ret;
ret = bdi_init(bdi);
if (!ret)
ret = bdi_register(bdi, NULL, "%s", name);
if (ret)
bdi_destroy(bdi);
return ret;
}
static struct proc_dir_entry *proc_mtd;
static int __init init_mtd(void)
{
int ret;
ret = class_register(&mtd_class);
if (ret)
goto err_reg;
ret = mtd_bdi_init(&mtd_bdi_unmappable, "mtd-unmap");
if (ret)
goto err_bdi1;
ret = mtd_bdi_init(&mtd_bdi_ro_mappable, "mtd-romap");
if (ret)
goto err_bdi2;
ret = mtd_bdi_init(&mtd_bdi_rw_mappable, "mtd-rwmap");
if (ret)
goto err_bdi3;
proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
ret = init_mtdchar();
if (ret)
goto out_procfs;
return 0;
out_procfs:
if (proc_mtd)
remove_proc_entry("mtd", NULL);
err_bdi3:
bdi_destroy(&mtd_bdi_ro_mappable);
err_bdi2:
bdi_destroy(&mtd_bdi_unmappable);
err_bdi1:
class_unregister(&mtd_class);
err_reg:
pr_err("Error registering mtd class or bdi: %d\n", ret);
return ret;
}
static void __exit cleanup_mtd(void)
{
cleanup_mtdchar();
if (proc_mtd)
remove_proc_entry("mtd", NULL);
class_unregister(&mtd_class);
bdi_destroy(&mtd_bdi_unmappable);
bdi_destroy(&mtd_bdi_ro_mappable);
bdi_destroy(&mtd_bdi_rw_mappable);
}
module_init(init_mtd);
module_exit(cleanup_mtd);
#endif
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Core MTD registration and access routines");
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