894 lines
22 KiB
C
894 lines
22 KiB
C
/*
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* Core registration and callback routines for MTD
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* drivers and users.
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*
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* Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
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* Copyright © 2006 Red Hat UK Limited
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/ptrace.h>
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#include <linux/seq_file.h>
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#include <linux/string.h>
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#include <linux/timer.h>
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#include <linux/major.h>
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#include <linux/fs.h>
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#include <linux/err.h>
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#include <linux/ioctl.h>
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#include <linux/init.h>
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#include <linux/proc_fs.h>
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#include <linux/idr.h>
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#include <linux/backing-dev.h>
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#include <linux/gfp.h>
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#include <linux/mtd/mtd.h>
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#include <linux/mtd/partitions.h>
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#include "mtdcore.h"
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/*
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* backing device capabilities for non-mappable devices (such as NAND flash)
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* - permits private mappings, copies are taken of the data
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*/
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static struct backing_dev_info mtd_bdi_unmappable = {
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.capabilities = BDI_CAP_MAP_COPY,
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};
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/*
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* backing device capabilities for R/O mappable devices (such as ROM)
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* - permits private mappings, copies are taken of the data
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* - permits non-writable shared mappings
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*/
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static struct backing_dev_info mtd_bdi_ro_mappable = {
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.capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
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BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP),
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};
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/*
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* backing device capabilities for writable mappable devices (such as RAM)
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* - permits private mappings, copies are taken of the data
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* - permits non-writable shared mappings
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*/
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static struct backing_dev_info mtd_bdi_rw_mappable = {
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.capabilities = (BDI_CAP_MAP_COPY | BDI_CAP_MAP_DIRECT |
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BDI_CAP_EXEC_MAP | BDI_CAP_READ_MAP |
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BDI_CAP_WRITE_MAP),
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};
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static int mtd_cls_suspend(struct device *dev, pm_message_t state);
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static int mtd_cls_resume(struct device *dev);
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static struct class mtd_class = {
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.name = "mtd",
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.owner = THIS_MODULE,
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.suspend = mtd_cls_suspend,
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.resume = mtd_cls_resume,
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};
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static DEFINE_IDR(mtd_idr);
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/* These are exported solely for the purpose of mtd_blkdevs.c. You
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should not use them for _anything_ else */
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DEFINE_MUTEX(mtd_table_mutex);
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EXPORT_SYMBOL_GPL(mtd_table_mutex);
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struct mtd_info *__mtd_next_device(int i)
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{
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return idr_get_next(&mtd_idr, &i);
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}
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EXPORT_SYMBOL_GPL(__mtd_next_device);
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static LIST_HEAD(mtd_notifiers);
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#if defined(CONFIG_MTD_CHAR) || defined(CONFIG_MTD_CHAR_MODULE)
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#define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
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#else
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#define MTD_DEVT(index) 0
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#endif
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/* REVISIT once MTD uses the driver model better, whoever allocates
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* the mtd_info will probably want to use the release() hook...
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*/
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static void mtd_release(struct device *dev)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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dev_t index = MTD_DEVT(mtd->index);
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/* remove /dev/mtdXro node if needed */
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if (index)
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device_destroy(&mtd_class, index + 1);
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}
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static int mtd_cls_suspend(struct device *dev, pm_message_t state)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return mtd ? mtd_suspend(mtd) : 0;
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}
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static int mtd_cls_resume(struct device *dev)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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if (mtd && mtd->resume)
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mtd_resume(mtd);
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return 0;
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}
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static ssize_t mtd_type_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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char *type;
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switch (mtd->type) {
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case MTD_ABSENT:
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type = "absent";
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break;
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case MTD_RAM:
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type = "ram";
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break;
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case MTD_ROM:
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type = "rom";
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break;
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case MTD_NORFLASH:
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type = "nor";
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break;
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case MTD_NANDFLASH:
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type = "nand";
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break;
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case MTD_DATAFLASH:
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type = "dataflash";
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break;
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case MTD_UBIVOLUME:
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type = "ubi";
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break;
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default:
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type = "unknown";
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}
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return snprintf(buf, PAGE_SIZE, "%s\n", type);
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}
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static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
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static ssize_t mtd_flags_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
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}
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static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
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static ssize_t mtd_size_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%llu\n",
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(unsigned long long)mtd->size);
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}
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static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
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static ssize_t mtd_erasesize_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
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}
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static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
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static ssize_t mtd_writesize_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
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}
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static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
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static ssize_t mtd_subpagesize_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
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return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
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}
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static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
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static ssize_t mtd_oobsize_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
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}
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static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
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static ssize_t mtd_numeraseregions_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
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}
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static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
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NULL);
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static ssize_t mtd_name_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct mtd_info *mtd = dev_get_drvdata(dev);
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return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
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}
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static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
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static struct attribute *mtd_attrs[] = {
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&dev_attr_type.attr,
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&dev_attr_flags.attr,
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&dev_attr_size.attr,
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&dev_attr_erasesize.attr,
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&dev_attr_writesize.attr,
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&dev_attr_subpagesize.attr,
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&dev_attr_oobsize.attr,
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&dev_attr_numeraseregions.attr,
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&dev_attr_name.attr,
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NULL,
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};
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static struct attribute_group mtd_group = {
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.attrs = mtd_attrs,
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};
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static const struct attribute_group *mtd_groups[] = {
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&mtd_group,
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NULL,
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};
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static struct device_type mtd_devtype = {
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.name = "mtd",
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.groups = mtd_groups,
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.release = mtd_release,
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};
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/**
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* add_mtd_device - register an MTD device
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* @mtd: pointer to new MTD device info structure
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*
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* Add a device to the list of MTD devices present in the system, and
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* notify each currently active MTD 'user' of its arrival. Returns
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* zero on success or 1 on failure, which currently will only happen
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* if there is insufficient memory or a sysfs error.
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*/
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int add_mtd_device(struct mtd_info *mtd)
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{
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struct mtd_notifier *not;
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int i, error;
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if (!mtd->backing_dev_info) {
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switch (mtd->type) {
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case MTD_RAM:
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mtd->backing_dev_info = &mtd_bdi_rw_mappable;
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break;
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case MTD_ROM:
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mtd->backing_dev_info = &mtd_bdi_ro_mappable;
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break;
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default:
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mtd->backing_dev_info = &mtd_bdi_unmappable;
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break;
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}
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}
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BUG_ON(mtd->writesize == 0);
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mutex_lock(&mtd_table_mutex);
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do {
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if (!idr_pre_get(&mtd_idr, GFP_KERNEL))
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goto fail_locked;
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error = idr_get_new(&mtd_idr, mtd, &i);
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} while (error == -EAGAIN);
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if (error)
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goto fail_locked;
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mtd->index = i;
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mtd->usecount = 0;
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if (is_power_of_2(mtd->erasesize))
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mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
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else
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mtd->erasesize_shift = 0;
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if (is_power_of_2(mtd->writesize))
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mtd->writesize_shift = ffs(mtd->writesize) - 1;
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else
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mtd->writesize_shift = 0;
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mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
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mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
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/* Some chips always power up locked. Unlock them now */
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if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
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error = mtd_unlock(mtd, 0, mtd->size);
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if (error && error != -EOPNOTSUPP)
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printk(KERN_WARNING
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"%s: unlock failed, writes may not work\n",
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mtd->name);
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}
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/* Caller should have set dev.parent to match the
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* physical device.
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*/
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mtd->dev.type = &mtd_devtype;
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mtd->dev.class = &mtd_class;
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mtd->dev.devt = MTD_DEVT(i);
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dev_set_name(&mtd->dev, "mtd%d", i);
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dev_set_drvdata(&mtd->dev, mtd);
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if (device_register(&mtd->dev) != 0)
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goto fail_added;
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if (MTD_DEVT(i))
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device_create(&mtd_class, mtd->dev.parent,
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MTD_DEVT(i) + 1,
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NULL, "mtd%dro", i);
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pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
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/* No need to get a refcount on the module containing
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the notifier, since we hold the mtd_table_mutex */
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list_for_each_entry(not, &mtd_notifiers, list)
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not->add(mtd);
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mutex_unlock(&mtd_table_mutex);
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/* We _know_ we aren't being removed, because
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our caller is still holding us here. So none
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of this try_ nonsense, and no bitching about it
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either. :) */
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__module_get(THIS_MODULE);
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return 0;
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fail_added:
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idr_remove(&mtd_idr, i);
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fail_locked:
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mutex_unlock(&mtd_table_mutex);
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return 1;
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}
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/**
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* del_mtd_device - unregister an MTD device
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* @mtd: pointer to MTD device info structure
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*
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* Remove a device from the list of MTD devices present in the system,
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* and notify each currently active MTD 'user' of its departure.
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* Returns zero on success or 1 on failure, which currently will happen
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* if the requested device does not appear to be present in the list.
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*/
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int del_mtd_device(struct mtd_info *mtd)
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{
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int ret;
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struct mtd_notifier *not;
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mutex_lock(&mtd_table_mutex);
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if (idr_find(&mtd_idr, mtd->index) != mtd) {
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ret = -ENODEV;
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goto out_error;
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}
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/* No need to get a refcount on the module containing
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the notifier, since we hold the mtd_table_mutex */
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list_for_each_entry(not, &mtd_notifiers, list)
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not->remove(mtd);
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if (mtd->usecount) {
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printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
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mtd->index, mtd->name, mtd->usecount);
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ret = -EBUSY;
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} else {
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device_unregister(&mtd->dev);
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idr_remove(&mtd_idr, mtd->index);
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module_put(THIS_MODULE);
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ret = 0;
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}
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out_error:
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mutex_unlock(&mtd_table_mutex);
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return ret;
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}
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/**
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* mtd_device_parse_register - parse partitions and register an MTD device.
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*
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* @mtd: the MTD device to register
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* @types: the list of MTD partition probes to try, see
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* 'parse_mtd_partitions()' for more information
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* @parser_data: MTD partition parser-specific data
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* @parts: fallback partition information to register, if parsing fails;
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* only valid if %nr_parts > %0
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* @nr_parts: the number of partitions in parts, if zero then the full
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* MTD device is registered if no partition info is found
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*
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* This function aggregates MTD partitions parsing (done by
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* 'parse_mtd_partitions()') and MTD device and partitions registering. It
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* basically follows the most common pattern found in many MTD drivers:
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*
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* * It first tries to probe partitions on MTD device @mtd using parsers
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* specified in @types (if @types is %NULL, then the default list of parsers
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* is used, see 'parse_mtd_partitions()' for more information). If none are
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* found this functions tries to fallback to information specified in
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* @parts/@nr_parts.
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* * If any partitioning info was found, this function registers the found
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* partitions.
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* * If no partitions were found this function just registers the MTD device
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* @mtd and exits.
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*
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* Returns zero in case of success and a negative error code in case of failure.
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*/
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int mtd_device_parse_register(struct mtd_info *mtd, const char **types,
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struct mtd_part_parser_data *parser_data,
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const struct mtd_partition *parts,
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int nr_parts)
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{
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int err;
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struct mtd_partition *real_parts;
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err = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
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if (err <= 0 && nr_parts && parts) {
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real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
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GFP_KERNEL);
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if (!real_parts)
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err = -ENOMEM;
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else
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err = nr_parts;
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}
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if (err > 0) {
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err = add_mtd_partitions(mtd, real_parts, err);
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kfree(real_parts);
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} else if (err == 0) {
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err = add_mtd_device(mtd);
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if (err == 1)
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err = -ENODEV;
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}
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return err;
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}
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EXPORT_SYMBOL_GPL(mtd_device_parse_register);
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/**
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* mtd_device_unregister - unregister an existing MTD device.
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*
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* @master: the MTD device to unregister. This will unregister both the master
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* and any partitions if registered.
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*/
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int mtd_device_unregister(struct mtd_info *master)
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{
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int err;
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err = del_mtd_partitions(master);
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if (err)
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return err;
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if (!device_is_registered(&master->dev))
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return 0;
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return del_mtd_device(master);
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|
}
|
|
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);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
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);
|
|
|
|
/*
|
|
* 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->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);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
/*====================================================================*/
|
|
/* Support for /proc/mtd */
|
|
|
|
static struct proc_dir_entry *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 */
|
|
|
|
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, name);
|
|
|
|
if (ret)
|
|
bdi_destroy(bdi);
|
|
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
|
|
#endif /* CONFIG_PROC_FS */
|
|
return 0;
|
|
|
|
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)
|
|
{
|
|
#ifdef CONFIG_PROC_FS
|
|
if (proc_mtd)
|
|
remove_proc_entry( "mtd", NULL);
|
|
#endif /* CONFIG_PROC_FS */
|
|
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);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
|
|
MODULE_DESCRIPTION("Core MTD registration and access routines");
|