linux-imx

/*

 * NFTL mount code with extensive checks

 *

 * Author: Fabrice Bellard (fabrice.bellard@netgem.com)

 * Copyright © 2000 Netgem S.A.

 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

​

#include <linux/kernel.h>

#include <asm/errno.h>

#include <linux/delay.h>

#include <linux/slab.h>

#include <linux/mtd/mtd.h>

#include <linux/mtd/rawnand.h>

#include <linux/mtd/nftl.h>

​

#define SECTORSIZE 512

​

/* find_boot_record: Find the NFTL Media Header and its Spare copy which contains the

 *  various device information of the NFTL partition and Bad Unit Table. Update

 *  the ReplUnitTable[] table according to the Bad Unit Table. ReplUnitTable[]

 *  is used for management of Erase Unit in other routines in nftl.c and nftlmount.c

 */

static int find_boot_record(struct NFTLrecord *nftl)

{

    struct nftl_uci1 h1;

    unsigned int block, boot_record_count = 0;

    size_t retlen;

    u8 buf[SECTORSIZE];

    struct NFTLMediaHeader *mh = &nftl->MediaHdr;

    struct mtd_info *mtd = nftl->mbd.mtd;

    unsigned int i;

​

        /* Assume logical EraseSize == physical erasesize for starting the scan.

       We'll sort it out later if we find a MediaHeader which says otherwise */

    /* Actually, we won't.  The new DiskOnChip driver has already scanned

       the MediaHeader and adjusted the virtual erasesize it presents in

       the mtd device accordingly.  We could even get rid of

       nftl->EraseSize if there were any point in doing so. */

    nftl->EraseSize = nftl->mbd.mtd->erasesize;

        nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize;

​

    nftl->MediaUnit = BLOCK_NIL;

    nftl->SpareMediaUnit = BLOCK_NIL;

​

    /* search for a valid boot record */

    for (block = 0; block < nftl->nb_blocks; block++) {

        int ret;

​

        /* Check for ANAND header first. Then can whinge if it's found but later

           checks fail */

        ret = mtd_read(mtd, block * nftl->EraseSize, SECTORSIZE,

                   &retlen, buf);

        /* We ignore ret in case the ECC of the MediaHeader is invalid

           (which is apparently acceptable) */

        if (retlen != SECTORSIZE) {

            static int warncount = 5;

​

            if (warncount) {

                printk(KERN_WARNING "Block read at 0x%x of mtd%d failed: %d\n",

                       block * nftl->EraseSize, nftl->mbd.mtd->index, ret);

                if (!--warncount)

                    printk(KERN_WARNING "Further failures for this block will not be printed\n");

            }

            continue;

        }

​

        if (retlen < 6 || memcmp(buf, "ANAND", 6)) {

            /* ANAND\0 not found. Continue */

#if 0

            printk(KERN_DEBUG "ANAND header not found at 0x%x in mtd%d\n",

                   block * nftl->EraseSize, nftl->mbd.mtd->index);

#endif

            continue;

        }

​

        /* To be safer with BIOS, also use erase mark as discriminant */

        ret = nftl_read_oob(mtd, block * nftl->EraseSize +