805 lines
22 KiB
C
805 lines
22 KiB
C
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// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Linux driver for NAND Flash Translation Layer
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*
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* Copyright © 1999 Machine Vision Holdings, Inc.
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* Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
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*/
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#define PRERELEASE
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <asm/errno.h>
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#include <asm/io.h>
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#include <linux/uaccess.h>
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#include <linux/delay.h>
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#include <linux/slab.h>
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#include <linux/init.h>
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#include <linux/hdreg.h>
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#include <linux/blkdev.h>
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#include <linux/kmod.h>
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#include <linux/mtd/mtd.h>
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#include <linux/mtd/rawnand.h>
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#include <linux/mtd/nftl.h>
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#include <linux/mtd/blktrans.h>
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/* maximum number of loops while examining next block, to have a
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chance to detect consistency problems (they should never happen
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because of the checks done in the mounting */
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#define MAX_LOOPS 10000
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static void nftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
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{
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struct NFTLrecord *nftl;
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unsigned long temp;
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if (!mtd_type_is_nand(mtd) || mtd->size > UINT_MAX)
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return;
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/* OK, this is moderately ugly. But probably safe. Alternatives? */
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if (memcmp(mtd->name, "DiskOnChip", 10))
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return;
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pr_debug("NFTL: add_mtd for %s\n", mtd->name);
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nftl = kzalloc(sizeof(struct NFTLrecord), GFP_KERNEL);
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if (!nftl)
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return;
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nftl->mbd.mtd = mtd;
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nftl->mbd.devnum = -1;
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nftl->mbd.tr = tr;
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if (NFTL_mount(nftl) < 0) {
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printk(KERN_WARNING "NFTL: could not mount device\n");
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kfree(nftl);
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return;
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}
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/* OK, it's a new one. Set up all the data structures. */
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/* Calculate geometry */
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nftl->cylinders = 1024;
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nftl->heads = 16;
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temp = nftl->cylinders * nftl->heads;
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nftl->sectors = nftl->mbd.size / temp;
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if (nftl->mbd.size % temp) {
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nftl->sectors++;
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temp = nftl->cylinders * nftl->sectors;
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nftl->heads = nftl->mbd.size / temp;
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if (nftl->mbd.size % temp) {
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nftl->heads++;
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temp = nftl->heads * nftl->sectors;
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nftl->cylinders = nftl->mbd.size / temp;
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}
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}
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if (nftl->mbd.size != nftl->heads * nftl->cylinders * nftl->sectors) {
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/*
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Oh no we don't have
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mbd.size == heads * cylinders * sectors
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*/
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printk(KERN_WARNING "NFTL: cannot calculate a geometry to "
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"match size of 0x%lx.\n", nftl->mbd.size);
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printk(KERN_WARNING "NFTL: using C:%d H:%d S:%d "
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"(== 0x%lx sects)\n",
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nftl->cylinders, nftl->heads , nftl->sectors,
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(long)nftl->cylinders * (long)nftl->heads *
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(long)nftl->sectors );
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}
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if (add_mtd_blktrans_dev(&nftl->mbd)) {
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kfree(nftl->ReplUnitTable);
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kfree(nftl->EUNtable);
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kfree(nftl);
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return;
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}
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#ifdef PSYCHO_DEBUG
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printk(KERN_INFO "NFTL: Found new nftl%c\n", nftl->mbd.devnum + 'a');
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#endif
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}
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static void nftl_remove_dev(struct mtd_blktrans_dev *dev)
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{
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struct NFTLrecord *nftl = (void *)dev;
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pr_debug("NFTL: remove_dev (i=%d)\n", dev->devnum);
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del_mtd_blktrans_dev(dev);
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kfree(nftl->ReplUnitTable);
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kfree(nftl->EUNtable);
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}
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/*
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* Read oob data from flash
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*/
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int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len,
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size_t *retlen, uint8_t *buf)
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{
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loff_t mask = mtd->writesize - 1;
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struct mtd_oob_ops ops = { };
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int res;
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ops.mode = MTD_OPS_PLACE_OOB;
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ops.ooboffs = offs & mask;
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ops.ooblen = len;
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ops.oobbuf = buf;
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ops.datbuf = NULL;
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res = mtd_read_oob(mtd, offs & ~mask, &ops);
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*retlen = ops.oobretlen;
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return res;
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}
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/*
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* Write oob data to flash
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*/
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int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len,
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size_t *retlen, uint8_t *buf)
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{
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loff_t mask = mtd->writesize - 1;
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struct mtd_oob_ops ops = { };
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int res;
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ops.mode = MTD_OPS_PLACE_OOB;
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ops.ooboffs = offs & mask;
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ops.ooblen = len;
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ops.oobbuf = buf;
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ops.datbuf = NULL;
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res = mtd_write_oob(mtd, offs & ~mask, &ops);
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*retlen = ops.oobretlen;
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return res;
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}
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#ifdef CONFIG_NFTL_RW
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/*
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* Write data and oob to flash
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*/
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static int nftl_write(struct mtd_info *mtd, loff_t offs, size_t len,
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size_t *retlen, uint8_t *buf, uint8_t *oob)
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{
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loff_t mask = mtd->writesize - 1;
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struct mtd_oob_ops ops = { };
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int res;
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ops.mode = MTD_OPS_PLACE_OOB;
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ops.ooboffs = offs & mask;
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ops.ooblen = mtd->oobsize;
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ops.oobbuf = oob;
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ops.datbuf = buf;
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ops.len = len;
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res = mtd_write_oob(mtd, offs & ~mask, &ops);
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*retlen = ops.retlen;
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return res;
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}
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/* Actual NFTL access routines */
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/* NFTL_findfreeblock: Find a free Erase Unit on the NFTL partition. This function is used
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* when the give Virtual Unit Chain
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*/
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static u16 NFTL_findfreeblock(struct NFTLrecord *nftl, int desperate )
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{
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/* For a given Virtual Unit Chain: find or create a free block and
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add it to the chain */
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/* We're passed the number of the last EUN in the chain, to save us from
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having to look it up again */
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u16 pot = nftl->LastFreeEUN;
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int silly = nftl->nb_blocks;
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/* Normally, we force a fold to happen before we run out of free blocks completely */
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if (!desperate && nftl->numfreeEUNs < 2) {
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pr_debug("NFTL_findfreeblock: there are too few free EUNs\n");
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return BLOCK_NIL;
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}
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/* Scan for a free block */
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do {
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if (nftl->ReplUnitTable[pot] == BLOCK_FREE) {
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nftl->LastFreeEUN = pot;
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nftl->numfreeEUNs--;
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return pot;
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}
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/* This will probably point to the MediaHdr unit itself,
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right at the beginning of the partition. But that unit
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(and the backup unit too) should have the UCI set
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up so that it's not selected for overwriting */
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if (++pot > nftl->lastEUN)
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pot = le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN);
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if (!silly--) {
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printk("Argh! No free blocks found! LastFreeEUN = %d, "
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"FirstEUN = %d\n", nftl->LastFreeEUN,
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le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN));
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return BLOCK_NIL;
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}
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} while (pot != nftl->LastFreeEUN);
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return BLOCK_NIL;
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}
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static u16 NFTL_foldchain (struct NFTLrecord *nftl, unsigned thisVUC, unsigned pendingblock )
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{
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struct mtd_info *mtd = nftl->mbd.mtd;
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u16 BlockMap[MAX_SECTORS_PER_UNIT];
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unsigned char BlockLastState[MAX_SECTORS_PER_UNIT];
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unsigned char BlockFreeFound[MAX_SECTORS_PER_UNIT];
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unsigned int thisEUN;
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int block;
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int silly;
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unsigned int targetEUN;
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struct nftl_oob oob;
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int inplace = 1;
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size_t retlen;
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memset(BlockMap, 0xff, sizeof(BlockMap));
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memset(BlockFreeFound, 0, sizeof(BlockFreeFound));
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thisEUN = nftl->EUNtable[thisVUC];
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if (thisEUN == BLOCK_NIL) {
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printk(KERN_WARNING "Trying to fold non-existent "
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"Virtual Unit Chain %d!\n", thisVUC);
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return BLOCK_NIL;
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}
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/* Scan to find the Erase Unit which holds the actual data for each
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512-byte block within the Chain.
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*/
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silly = MAX_LOOPS;
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targetEUN = BLOCK_NIL;
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while (thisEUN <= nftl->lastEUN ) {
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unsigned int status, foldmark;
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targetEUN = thisEUN;
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for (block = 0; block < nftl->EraseSize / 512; block ++) {
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nftl_read_oob(mtd, (thisEUN * nftl->EraseSize) +
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(block * 512), 16 , &retlen,
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(char *)&oob);
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if (block == 2) {
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foldmark = oob.u.c.FoldMark | oob.u.c.FoldMark1;
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if (foldmark == FOLD_MARK_IN_PROGRESS) {
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pr_debug("Write Inhibited on EUN %d\n", thisEUN);
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inplace = 0;
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} else {
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/* There's no other reason not to do inplace,
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except ones that come later. So we don't need
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to preserve inplace */
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inplace = 1;
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}
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}
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status = oob.b.Status | oob.b.Status1;
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BlockLastState[block] = status;
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switch(status) {
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case SECTOR_FREE:
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BlockFreeFound[block] = 1;
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break;
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case SECTOR_USED:
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if (!BlockFreeFound[block])
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BlockMap[block] = thisEUN;
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else
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printk(KERN_WARNING
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"SECTOR_USED found after SECTOR_FREE "
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"in Virtual Unit Chain %d for block %d\n",
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thisVUC, block);
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break;
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case SECTOR_DELETED:
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if (!BlockFreeFound[block])
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BlockMap[block] = BLOCK_NIL;
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else
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printk(KERN_WARNING
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"SECTOR_DELETED found after SECTOR_FREE "
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"in Virtual Unit Chain %d for block %d\n",
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thisVUC, block);
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break;
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case SECTOR_IGNORE:
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break;
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default:
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printk("Unknown status for block %d in EUN %d: %x\n",
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block, thisEUN, status);
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}
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}
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if (!silly--) {
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printk(KERN_WARNING "Infinite loop in Virtual Unit Chain 0x%x\n",
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thisVUC);
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return BLOCK_NIL;
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}
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thisEUN = nftl->ReplUnitTable[thisEUN];
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}
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if (inplace) {
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/* We're being asked to be a fold-in-place. Check
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that all blocks which actually have data associated
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with them (i.e. BlockMap[block] != BLOCK_NIL) are
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either already present or SECTOR_FREE in the target
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block. If not, we're going to have to fold out-of-place
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anyway.
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*/
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for (block = 0; block < nftl->EraseSize / 512 ; block++) {
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if (BlockLastState[block] != SECTOR_FREE &&
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BlockMap[block] != BLOCK_NIL &&
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BlockMap[block] != targetEUN) {
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pr_debug("Setting inplace to 0. VUC %d, "
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"block %d was %x lastEUN, "
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"and is in EUN %d (%s) %d\n",
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thisVUC, block, BlockLastState[block],
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BlockMap[block],
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BlockMap[block]== targetEUN ? "==" : "!=",
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targetEUN);
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inplace = 0;
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break;
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}
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}
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if (pendingblock >= (thisVUC * (nftl->EraseSize / 512)) &&
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pendingblock < ((thisVUC + 1)* (nftl->EraseSize / 512)) &&
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BlockLastState[pendingblock - (thisVUC * (nftl->EraseSize / 512))] !=
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SECTOR_FREE) {
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pr_debug("Pending write not free in EUN %d. "
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"Folding out of place.\n", targetEUN);
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inplace = 0;
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}
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}
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if (!inplace) {
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pr_debug("Cannot fold Virtual Unit Chain %d in place. "
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"Trying out-of-place\n", thisVUC);
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/* We need to find a targetEUN to fold into. */
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targetEUN = NFTL_findfreeblock(nftl, 1);
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if (targetEUN == BLOCK_NIL) {
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/* Ouch. Now we're screwed. We need to do a
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fold-in-place of another chain to make room
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for this one. We need a better way of selecting
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which chain to fold, because makefreeblock will
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only ask us to fold the same one again.
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*/
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printk(KERN_WARNING
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"NFTL_findfreeblock(desperate) returns 0xffff.\n");
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return BLOCK_NIL;
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}
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} else {
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/* We put a fold mark in the chain we are folding only if we
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fold in place to help the mount check code. If we do not fold in
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place, it is possible to find the valid chain by selecting the
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longer one */
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oob.u.c.FoldMark = oob.u.c.FoldMark1 = cpu_to_le16(FOLD_MARK_IN_PROGRESS);
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oob.u.c.unused = 0xffffffff;
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nftl_write_oob(mtd, (nftl->EraseSize * targetEUN) + 2 * 512 + 8,
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8, &retlen, (char *)&oob.u);
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}
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/* OK. We now know the location of every block in the Virtual Unit Chain,
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and the Erase Unit into which we are supposed to be copying.
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Go for it.
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*/
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pr_debug("Folding chain %d into unit %d\n", thisVUC, targetEUN);
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for (block = 0; block < nftl->EraseSize / 512 ; block++) {
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unsigned char movebuf[512];
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int ret;
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/* If it's in the target EUN already, or if it's pending write, do nothing */
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if (BlockMap[block] == targetEUN ||
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(pendingblock == (thisVUC * (nftl->EraseSize / 512) + block))) {
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continue;
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}
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/* copy only in non free block (free blocks can only
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happen in case of media errors or deleted blocks) */
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if (BlockMap[block] == BLOCK_NIL)
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continue;
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ret = mtd_read(mtd,
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(nftl->EraseSize * BlockMap[block]) + (block * 512),
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512,
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&retlen,
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movebuf);
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if (ret < 0 && !mtd_is_bitflip(ret)) {
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ret = mtd_read(mtd,
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(nftl->EraseSize * BlockMap[block]) + (block * 512),
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512,
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&retlen,
|
||
|
movebuf);
|
||
|
if (ret != -EIO)
|
||
|
printk("Error went away on retry.\n");
|
||
|
}
|
||
|
memset(&oob, 0xff, sizeof(struct nftl_oob));
|
||
|
oob.b.Status = oob.b.Status1 = SECTOR_USED;
|
||
|
|
||
|
nftl_write(nftl->mbd.mtd, (nftl->EraseSize * targetEUN) +
|
||
|
(block * 512), 512, &retlen, movebuf, (char *)&oob);
|
||
|
}
|
||
|
|
||
|
/* add the header so that it is now a valid chain */
|
||
|
oob.u.a.VirtUnitNum = oob.u.a.SpareVirtUnitNum = cpu_to_le16(thisVUC);
|
||
|
oob.u.a.ReplUnitNum = oob.u.a.SpareReplUnitNum = BLOCK_NIL;
|
||
|
|
||
|
nftl_write_oob(mtd, (nftl->EraseSize * targetEUN) + 8,
|
||
|
8, &retlen, (char *)&oob.u);
|
||
|
|
||
|
/* OK. We've moved the whole lot into the new block. Now we have to free the original blocks. */
|
||
|
|
||
|
/* At this point, we have two different chains for this Virtual Unit, and no way to tell
|
||
|
them apart. If we crash now, we get confused. However, both contain the same data, so we
|
||
|
shouldn't actually lose data in this case. It's just that when we load up on a medium which
|
||
|
has duplicate chains, we need to free one of the chains because it's not necessary any more.
|
||
|
*/
|
||
|
thisEUN = nftl->EUNtable[thisVUC];
|
||
|
pr_debug("Want to erase\n");
|
||
|
|
||
|
/* For each block in the old chain (except the targetEUN of course),
|
||
|
free it and make it available for future use */
|
||
|
while (thisEUN <= nftl->lastEUN && thisEUN != targetEUN) {
|
||
|
unsigned int EUNtmp;
|
||
|
|
||
|
EUNtmp = nftl->ReplUnitTable[thisEUN];
|
||
|
|
||
|
if (NFTL_formatblock(nftl, thisEUN) < 0) {
|
||
|
/* could not erase : mark block as reserved
|
||
|
*/
|
||
|
nftl->ReplUnitTable[thisEUN] = BLOCK_RESERVED;
|
||
|
} else {
|
||
|
/* correctly erased : mark it as free */
|
||
|
nftl->ReplUnitTable[thisEUN] = BLOCK_FREE;
|
||
|
nftl->numfreeEUNs++;
|
||
|
}
|
||
|
thisEUN = EUNtmp;
|
||
|
}
|
||
|
|
||
|
/* Make this the new start of chain for thisVUC */
|
||
|
nftl->ReplUnitTable[targetEUN] = BLOCK_NIL;
|
||
|
nftl->EUNtable[thisVUC] = targetEUN;
|
||
|
|
||
|
return targetEUN;
|
||
|
}
|
||
|
|
||
|
static u16 NFTL_makefreeblock( struct NFTLrecord *nftl , unsigned pendingblock)
|
||
|
{
|
||
|
/* This is the part that needs some cleverness applied.
|
||
|
For now, I'm doing the minimum applicable to actually
|
||
|
get the thing to work.
|
||
|
Wear-levelling and other clever stuff needs to be implemented
|
||
|
and we also need to do some assessment of the results when
|
||
|
the system loses power half-way through the routine.
|
||
|
*/
|
||
|
u16 LongestChain = 0;
|
||
|
u16 ChainLength = 0, thislen;
|
||
|
u16 chain, EUN;
|
||
|
|
||
|
for (chain = 0; chain < le32_to_cpu(nftl->MediaHdr.FormattedSize) / nftl->EraseSize; chain++) {
|
||
|
EUN = nftl->EUNtable[chain];
|
||
|
thislen = 0;
|
||
|
|
||
|
while (EUN <= nftl->lastEUN) {
|
||
|
thislen++;
|
||
|
//printk("VUC %d reaches len %d with EUN %d\n", chain, thislen, EUN);
|
||
|
EUN = nftl->ReplUnitTable[EUN] & 0x7fff;
|
||
|
if (thislen > 0xff00) {
|
||
|
printk("Endless loop in Virtual Chain %d: Unit %x\n",
|
||
|
chain, EUN);
|
||
|
}
|
||
|
if (thislen > 0xff10) {
|
||
|
/* Actually, don't return failure. Just ignore this chain and
|
||
|
get on with it. */
|
||
|
thislen = 0;
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (thislen > ChainLength) {
|
||
|
//printk("New longest chain is %d with length %d\n", chain, thislen);
|
||
|
ChainLength = thislen;
|
||
|
LongestChain = chain;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (ChainLength < 2) {
|
||
|
printk(KERN_WARNING "No Virtual Unit Chains available for folding. "
|
||
|
"Failing request\n");
|
||
|
return BLOCK_NIL;
|
||
|
}
|
||
|
|
||
|
return NFTL_foldchain (nftl, LongestChain, pendingblock);
|
||
|
}
|
||
|
|
||
|
/* NFTL_findwriteunit: Return the unit number into which we can write
|
||
|
for this block. Make it available if it isn't already
|
||
|
*/
|
||
|
static inline u16 NFTL_findwriteunit(struct NFTLrecord *nftl, unsigned block)
|
||
|
{
|
||
|
u16 lastEUN;
|
||
|
u16 thisVUC = block / (nftl->EraseSize / 512);
|
||
|
struct mtd_info *mtd = nftl->mbd.mtd;
|
||
|
unsigned int writeEUN;
|
||
|
unsigned long blockofs = (block * 512) & (nftl->EraseSize -1);
|
||
|
size_t retlen;
|
||
|
int silly, silly2 = 3;
|
||
|
struct nftl_oob oob;
|
||
|
|
||
|
do {
|
||
|
/* Scan the media to find a unit in the VUC which has
|
||
|
a free space for the block in question.
|
||
|
*/
|
||
|
|
||
|
/* This condition catches the 0x[7f]fff cases, as well as
|
||
|
being a sanity check for past-end-of-media access
|
||
|
*/
|
||
|
lastEUN = BLOCK_NIL;
|
||
|
writeEUN = nftl->EUNtable[thisVUC];
|
||
|
silly = MAX_LOOPS;
|
||
|
while (writeEUN <= nftl->lastEUN) {
|
||
|
struct nftl_bci bci;
|
||
|
size_t retlen;
|
||
|
unsigned int status;
|
||
|
|
||
|
lastEUN = writeEUN;
|
||
|
|
||
|
nftl_read_oob(mtd,
|
||
|
(writeEUN * nftl->EraseSize) + blockofs,
|
||
|
8, &retlen, (char *)&bci);
|
||
|
|
||
|
pr_debug("Status of block %d in EUN %d is %x\n",
|
||
|
block , writeEUN, le16_to_cpu(bci.Status));
|
||
|
|
||
|
status = bci.Status | bci.Status1;
|
||
|
switch(status) {
|
||
|
case SECTOR_FREE:
|
||
|
return writeEUN;
|
||
|
|
||
|
case SECTOR_DELETED:
|
||
|
case SECTOR_USED:
|
||
|
case SECTOR_IGNORE:
|
||
|
break;
|
||
|
default:
|
||
|
// Invalid block. Don't use it any more. Must implement.
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
if (!silly--) {
|
||
|
printk(KERN_WARNING
|
||
|
"Infinite loop in Virtual Unit Chain 0x%x\n",
|
||
|
thisVUC);
|
||
|
return BLOCK_NIL;
|
||
|
}
|
||
|
|
||
|
/* Skip to next block in chain */
|
||
|
writeEUN = nftl->ReplUnitTable[writeEUN];
|
||
|
}
|
||
|
|
||
|
/* OK. We didn't find one in the existing chain, or there
|
||
|
is no existing chain. */
|
||
|
|
||
|
/* Try to find an already-free block */
|
||
|
writeEUN = NFTL_findfreeblock(nftl, 0);
|
||
|
|
||
|
if (writeEUN == BLOCK_NIL) {
|
||
|
/* That didn't work - there were no free blocks just
|
||
|
waiting to be picked up. We're going to have to fold
|
||
|
a chain to make room.
|
||
|
*/
|
||
|
|
||
|
/* First remember the start of this chain */
|
||
|
//u16 startEUN = nftl->EUNtable[thisVUC];
|
||
|
|
||
|
//printk("Write to VirtualUnitChain %d, calling makefreeblock()\n", thisVUC);
|
||
|
writeEUN = NFTL_makefreeblock(nftl, BLOCK_NIL);
|
||
|
|
||
|
if (writeEUN == BLOCK_NIL) {
|
||
|
/* OK, we accept that the above comment is
|
||
|
lying - there may have been free blocks
|
||
|
last time we called NFTL_findfreeblock(),
|
||
|
but they are reserved for when we're
|
||
|
desperate. Well, now we're desperate.
|
||
|
*/
|
||
|
pr_debug("Using desperate==1 to find free EUN to accommodate write to VUC %d\n", thisVUC);
|
||
|
writeEUN = NFTL_findfreeblock(nftl, 1);
|
||
|
}
|
||
|
if (writeEUN == BLOCK_NIL) {
|
||
|
/* Ouch. This should never happen - we should
|
||
|
always be able to make some room somehow.
|
||
|
If we get here, we've allocated more storage
|
||
|
space than actual media, or our makefreeblock
|
||
|
routine is missing something.
|
||
|
*/
|
||
|
printk(KERN_WARNING "Cannot make free space.\n");
|
||
|
return BLOCK_NIL;
|
||
|
}
|
||
|
//printk("Restarting scan\n");
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
/* We've found a free block. Insert it into the chain. */
|
||
|
|
||
|
if (lastEUN != BLOCK_NIL) {
|
||
|
thisVUC |= 0x8000; /* It's a replacement block */
|
||
|
} else {
|
||
|
/* The first block in a new chain */
|
||
|
nftl->EUNtable[thisVUC] = writeEUN;
|
||
|
}
|
||
|
|
||
|
/* set up the actual EUN we're writing into */
|
||
|
/* Both in our cache... */
|
||
|
nftl->ReplUnitTable[writeEUN] = BLOCK_NIL;
|
||
|
|
||
|
/* ... and on the flash itself */
|
||
|
nftl_read_oob(mtd, writeEUN * nftl->EraseSize + 8, 8,
|
||
|
&retlen, (char *)&oob.u);
|
||
|
|
||
|
oob.u.a.VirtUnitNum = oob.u.a.SpareVirtUnitNum = cpu_to_le16(thisVUC);
|
||
|
|
||
|
nftl_write_oob(mtd, writeEUN * nftl->EraseSize + 8, 8,
|
||
|
&retlen, (char *)&oob.u);
|
||
|
|
||
|
/* we link the new block to the chain only after the
|
||
|
block is ready. It avoids the case where the chain
|
||
|
could point to a free block */
|
||
|
if (lastEUN != BLOCK_NIL) {
|
||
|
/* Both in our cache... */
|
||
|
nftl->ReplUnitTable[lastEUN] = writeEUN;
|
||
|
/* ... and on the flash itself */
|
||
|
nftl_read_oob(mtd, (lastEUN * nftl->EraseSize) + 8,
|
||
|
8, &retlen, (char *)&oob.u);
|
||
|
|
||
|
oob.u.a.ReplUnitNum = oob.u.a.SpareReplUnitNum
|
||
|
= cpu_to_le16(writeEUN);
|
||
|
|
||
|
nftl_write_oob(mtd, (lastEUN * nftl->EraseSize) + 8,
|
||
|
8, &retlen, (char *)&oob.u);
|
||
|
}
|
||
|
|
||
|
return writeEUN;
|
||
|
|
||
|
} while (silly2--);
|
||
|
|
||
|
printk(KERN_WARNING "Error folding to make room for Virtual Unit Chain 0x%x\n",
|
||
|
thisVUC);
|
||
|
return BLOCK_NIL;
|
||
|
}
|
||
|
|
||
|
static int nftl_writeblock(struct mtd_blktrans_dev *mbd, unsigned long block,
|
||
|
char *buffer)
|
||
|
{
|
||
|
struct NFTLrecord *nftl = (void *)mbd;
|
||
|
u16 writeEUN;
|
||
|
unsigned long blockofs = (block * 512) & (nftl->EraseSize - 1);
|
||
|
size_t retlen;
|
||
|
struct nftl_oob oob;
|
||
|
|
||
|
writeEUN = NFTL_findwriteunit(nftl, block);
|
||
|
|
||
|
if (writeEUN == BLOCK_NIL) {
|
||
|
printk(KERN_WARNING
|
||
|
"NFTL_writeblock(): Cannot find block to write to\n");
|
||
|
/* If we _still_ haven't got a block to use, we're screwed */
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
memset(&oob, 0xff, sizeof(struct nftl_oob));
|
||
|
oob.b.Status = oob.b.Status1 = SECTOR_USED;
|
||
|
|
||
|
nftl_write(nftl->mbd.mtd, (writeEUN * nftl->EraseSize) + blockofs,
|
||
|
512, &retlen, (char *)buffer, (char *)&oob);
|
||
|
return 0;
|
||
|
}
|
||
|
#endif /* CONFIG_NFTL_RW */
|
||
|
|
||
|
static int nftl_readblock(struct mtd_blktrans_dev *mbd, unsigned long block,
|
||
|
char *buffer)
|
||
|
{
|
||
|
struct NFTLrecord *nftl = (void *)mbd;
|
||
|
struct mtd_info *mtd = nftl->mbd.mtd;
|
||
|
u16 lastgoodEUN;
|
||
|
u16 thisEUN = nftl->EUNtable[block / (nftl->EraseSize / 512)];
|
||
|
unsigned long blockofs = (block * 512) & (nftl->EraseSize - 1);
|
||
|
unsigned int status;
|
||
|
int silly = MAX_LOOPS;
|
||
|
size_t retlen;
|
||
|
struct nftl_bci bci;
|
||
|
|
||
|
lastgoodEUN = BLOCK_NIL;
|
||
|
|
||
|
if (thisEUN != BLOCK_NIL) {
|
||
|
while (thisEUN < nftl->nb_blocks) {
|
||
|
if (nftl_read_oob(mtd, (thisEUN * nftl->EraseSize) +
|
||
|
blockofs, 8, &retlen,
|
||
|
(char *)&bci) < 0)
|
||
|
status = SECTOR_IGNORE;
|
||
|
else
|
||
|
status = bci.Status | bci.Status1;
|
||
|
|
||
|
switch (status) {
|
||
|
case SECTOR_FREE:
|
||
|
/* no modification of a sector should follow a free sector */
|
||
|
goto the_end;
|
||
|
case SECTOR_DELETED:
|
||
|
lastgoodEUN = BLOCK_NIL;
|
||
|
break;
|
||
|
case SECTOR_USED:
|
||
|
lastgoodEUN = thisEUN;
|
||
|
break;
|
||
|
case SECTOR_IGNORE:
|
||
|
break;
|
||
|
default:
|
||
|
printk("Unknown status for block %ld in EUN %d: %x\n",
|
||
|
block, thisEUN, status);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
if (!silly--) {
|
||
|
printk(KERN_WARNING "Infinite loop in Virtual Unit Chain 0x%lx\n",
|
||
|
block / (nftl->EraseSize / 512));
|
||
|
return 1;
|
||
|
}
|
||
|
thisEUN = nftl->ReplUnitTable[thisEUN];
|
||
|
}
|
||
|
}
|
||
|
|
||
|
the_end:
|
||
|
if (lastgoodEUN == BLOCK_NIL) {
|
||
|
/* the requested block is not on the media, return all 0x00 */
|
||
|
memset(buffer, 0, 512);
|
||
|
} else {
|
||
|
loff_t ptr = (lastgoodEUN * nftl->EraseSize) + blockofs;
|
||
|
size_t retlen;
|
||
|
int res = mtd_read(mtd, ptr, 512, &retlen, buffer);
|
||
|
|
||
|
if (res < 0 && !mtd_is_bitflip(res))
|
||
|
return -EIO;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int nftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
|
||
|
{
|
||
|
struct NFTLrecord *nftl = (void *)dev;
|
||
|
|
||
|
geo->heads = nftl->heads;
|
||
|
geo->sectors = nftl->sectors;
|
||
|
geo->cylinders = nftl->cylinders;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/****************************************************************************
|
||
|
*
|
||
|
* Module stuff
|
||
|
*
|
||
|
****************************************************************************/
|
||
|
|
||
|
|
||
|
static struct mtd_blktrans_ops nftl_tr = {
|
||
|
.name = "nftl",
|
||
|
.major = NFTL_MAJOR,
|
||
|
.part_bits = NFTL_PARTN_BITS,
|
||
|
.blksize = 512,
|
||
|
.getgeo = nftl_getgeo,
|
||
|
.readsect = nftl_readblock,
|
||
|
#ifdef CONFIG_NFTL_RW
|
||
|
.writesect = nftl_writeblock,
|
||
|
#endif
|
||
|
.add_mtd = nftl_add_mtd,
|
||
|
.remove_dev = nftl_remove_dev,
|
||
|
.owner = THIS_MODULE,
|
||
|
};
|
||
|
|
||
|
module_mtd_blktrans(nftl_tr);
|
||
|
|
||
|
MODULE_LICENSE("GPL");
|
||
|
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>, Fabrice Bellard <fabrice.bellard@netgem.com> et al.");
|
||
|
MODULE_DESCRIPTION("Support code for NAND Flash Translation Layer, used on M-Systems DiskOnChip 2000 and Millennium");
|
||
|
MODULE_ALIAS_BLOCKDEV_MAJOR(NFTL_MAJOR);
|