diff options
Diffstat (limited to 'drivers/mtd/nftlcore.c')
| -rw-r--r-- | drivers/mtd/nftlcore.c | 816 |
1 files changed, 816 insertions, 0 deletions
diff --git a/drivers/mtd/nftlcore.c b/drivers/mtd/nftlcore.c new file mode 100644 index 000000000..d44641129 --- /dev/null +++ b/drivers/mtd/nftlcore.c @@ -0,0 +1,816 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux driver for NAND Flash Translation Layer + * + * Copyright © 1999 Machine Vision Holdings, Inc. + * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> + */ + +#define PRERELEASE + +#include <linux/kernel.h> +#include <linux/module.h> +#include <asm/errno.h> +#include <asm/io.h> +#include <linux/uaccess.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/hdreg.h> +#include <linux/blkdev.h> + +#include <linux/kmod.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/rawnand.h> +#include <linux/mtd/nftl.h> +#include <linux/mtd/blktrans.h> + +/* maximum number of loops while examining next block, to have a + chance to detect consistency problems (they should never happen + because of the checks done in the mounting */ + +#define MAX_LOOPS 10000 + + +static void nftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) +{ + struct NFTLrecord *nftl; + unsigned long temp; + + if (!mtd_type_is_nand(mtd) || mtd->size > UINT_MAX) + return; + /* OK, this is moderately ugly. But probably safe. Alternatives? */ + if (memcmp(mtd->name, "DiskOnChip", 10)) + return; + + pr_debug("NFTL: add_mtd for %s\n", mtd->name); + + nftl = kzalloc(sizeof(struct NFTLrecord), GFP_KERNEL); + + if (!nftl) + return; + + nftl->mbd.mtd = mtd; + nftl->mbd.devnum = -1; + + nftl->mbd.tr = tr; + + if (NFTL_mount(nftl) < 0) { + printk(KERN_WARNING "NFTL: could not mount device\n"); + kfree(nftl); + return; + } + + /* OK, it's a new one. Set up all the data structures. */ + + /* Calculate geometry */ + nftl->cylinders = 1024; + nftl->heads = 16; + + temp = nftl->cylinders * nftl->heads; + nftl->sectors = nftl->mbd.size / temp; + if (nftl->mbd.size % temp) { + nftl->sectors++; + temp = nftl->cylinders * nftl->sectors; + nftl->heads = nftl->mbd.size / temp; + + if (nftl->mbd.size % temp) { + nftl->heads++; + temp = nftl->heads * nftl->sectors; + nftl->cylinders = nftl->mbd.size / temp; + } + } + + if (nftl->mbd.size != nftl->heads * nftl->cylinders * nftl->sectors) { + /* + Oh no we don't have + mbd.size == heads * cylinders * sectors + */ + printk(KERN_WARNING "NFTL: cannot calculate a geometry to " + "match size of 0x%lx.\n", nftl->mbd.size); + printk(KERN_WARNING "NFTL: using C:%d H:%d S:%d " + "(== 0x%lx sects)\n", + nftl->cylinders, nftl->heads , nftl->sectors, + (long)nftl->cylinders * (long)nftl->heads * + (long)nftl->sectors ); + } + + if (add_mtd_blktrans_dev(&nftl->mbd)) { + kfree(nftl->ReplUnitTable); + kfree(nftl->EUNtable); + kfree(nftl); + return; + } +#ifdef PSYCHO_DEBUG + printk(KERN_INFO "NFTL: Found new nftl%c\n", nftl->mbd.devnum + 'a'); +#endif +} + +static void nftl_remove_dev(struct mtd_blktrans_dev *dev) +{ + struct NFTLrecord *nftl = (void *)dev; + + pr_debug("NFTL: remove_dev (i=%d)\n", dev->devnum); + + del_mtd_blktrans_dev(dev); + kfree(nftl->ReplUnitTable); + kfree(nftl->EUNtable); +} + +/* + * Read oob data from flash + */ +int nftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, + size_t *retlen, uint8_t *buf) +{ + loff_t mask = mtd->writesize - 1; + struct mtd_oob_ops ops; + int res; + + ops.mode = MTD_OPS_PLACE_OOB; + ops.ooboffs = offs & mask; + ops.ooblen = len; + ops.oobbuf = buf; + ops.datbuf = NULL; + + res = mtd_read_oob(mtd, offs & ~mask, &ops); + *retlen = ops.oobretlen; + return res; +} + +/* + * Write oob data to flash + */ +int nftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, + size_t *retlen, uint8_t *buf) +{ + loff_t mask = mtd->writesize - 1; + struct mtd_oob_ops ops; + int res; + + ops.mode = MTD_OPS_PLACE_OOB; + ops.ooboffs = offs & mask; + ops.ooblen = len; + ops.oobbuf = buf; + ops.datbuf = NULL; + + res = mtd_write_oob(mtd, offs & ~mask, &ops); + *retlen = ops.oobretlen; + return res; +} + +#ifdef CONFIG_NFTL_RW + +/* + * Write data and oob to flash + */ +static int nftl_write(struct mtd_info *mtd, loff_t offs, size_t len, + size_t *retlen, uint8_t *buf, uint8_t *oob) +{ + loff_t mask = mtd->writesize - 1; + struct mtd_oob_ops ops; + int res; + + ops.mode = MTD_OPS_PLACE_OOB; + ops.ooboffs = offs & mask; + ops.ooblen = mtd->oobsize; + ops.oobbuf = oob; + ops.datbuf = buf; + ops.len = len; + + res = mtd_write_oob(mtd, offs & ~mask, &ops); + *retlen = ops.retlen; + return res; +} + +/* Actual NFTL access routines */ +/* NFTL_findfreeblock: Find a free Erase Unit on the NFTL partition. This function is used + * when the give Virtual Unit Chain + */ +static u16 NFTL_findfreeblock(struct NFTLrecord *nftl, int desperate ) +{ + /* For a given Virtual Unit Chain: find or create a free block and + add it to the chain */ + /* We're passed the number of the last EUN in the chain, to save us from + having to look it up again */ + u16 pot = nftl->LastFreeEUN; + int silly = nftl->nb_blocks; + + /* Normally, we force a fold to happen before we run out of free blocks completely */ + if (!desperate && nftl->numfreeEUNs < 2) { + pr_debug("NFTL_findfreeblock: there are too few free EUNs\n"); + return BLOCK_NIL; + } + + /* Scan for a free block */ + do { + if (nftl->ReplUnitTable[pot] == BLOCK_FREE) { + nftl->LastFreeEUN = pot; + nftl->numfreeEUNs--; + return pot; + } + + /* This will probably point to the MediaHdr unit itself, + right at the beginning of the partition. But that unit + (and the backup unit too) should have the UCI set + up so that it's not selected for overwriting */ + if (++pot > nftl->lastEUN) + pot = le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN); + + if (!silly--) { + printk("Argh! No free blocks found! LastFreeEUN = %d, " + "FirstEUN = %d\n", nftl->LastFreeEUN, + le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN)); + return BLOCK_NIL; + } + } while (pot != nftl->LastFreeEUN); + + return BLOCK_NIL; +} + +static u16 NFTL_foldchain (struct NFTLrecord *nftl, unsigned thisVUC, unsigned pendingblock ) +{ + struct mtd_info *mtd = nftl->mbd.mtd; + u16 BlockMap[MAX_SECTORS_PER_UNIT]; + unsigned char BlockLastState[MAX_SECTORS_PER_UNIT]; + unsigned char BlockFreeFound[MAX_SECTORS_PER_UNIT]; + unsigned int thisEUN; + int block; + int silly; + unsigned int targetEUN; + struct nftl_oob oob; + int inplace = 1; + size_t retlen; + + memset(BlockMap, 0xff, sizeof(BlockMap)); + memset(BlockFreeFound, 0, sizeof(BlockFreeFound)); + + thisEUN = nftl->EUNtable[thisVUC]; + + if (thisEUN == BLOCK_NIL) { + printk(KERN_WARNING "Trying to fold non-existent " + "Virtual Unit Chain %d!\n", thisVUC); + return BLOCK_NIL; + } + + /* Scan to find the Erase Unit which holds the actual data for each + 512-byte block within the Chain. + */ + silly = MAX_LOOPS; + targetEUN = BLOCK_NIL; + while (thisEUN <= nftl->lastEUN ) { + unsigned int status, foldmark; + + targetEUN = thisEUN; + for (block = 0; block < nftl->EraseSize / 512; block ++) { + nftl_read_oob(mtd, (thisEUN * nftl->EraseSize) + + (block * 512), 16 , &retlen, + (char *)&oob); + if (block == 2) { + foldmark = oob.u.c.FoldMark | oob.u.c.FoldMark1; + if (foldmark == FOLD_MARK_IN_PROGRESS) { + pr_debug("Write Inhibited on EUN %d\n", thisEUN); + inplace = 0; + } else { + /* There's no other reason not to do inplace, + except ones that come later. So we don't need + to preserve inplace */ + inplace = 1; + } + } + status = oob.b.Status | oob.b.Status1; + BlockLastState[block] = status; + + switch(status) { + case SECTOR_FREE: + BlockFreeFound[block] = 1; + break; + + case SECTOR_USED: + if (!BlockFreeFound[block]) + BlockMap[block] = thisEUN; + else + printk(KERN_WARNING + "SECTOR_USED found after SECTOR_FREE " + "in Virtual Unit Chain %d for block %d\n", + thisVUC, block); + break; + case SECTOR_DELETED: + if (!BlockFreeFound[block]) + BlockMap[block] = BLOCK_NIL; + else + printk(KERN_WARNING + "SECTOR_DELETED found after SECTOR_FREE " + "in Virtual Unit Chain %d for block %d\n", + thisVUC, block); + break; + + case SECTOR_IGNORE: + break; + default: + printk("Unknown status for block %d in EUN %d: %x\n", + block, thisEUN, status); + } + } + + if (!silly--) { + printk(KERN_WARNING "Infinite loop in Virtual Unit Chain 0x%x\n", + thisVUC); + return BLOCK_NIL; + } + + thisEUN = nftl->ReplUnitTable[thisEUN]; + } + + if (inplace) { + /* We're being asked to be a fold-in-place. Check + that all blocks which actually have data associated + with them (i.e. BlockMap[block] != BLOCK_NIL) are + either already present or SECTOR_FREE in the target + block. If not, we're going to have to fold out-of-place + anyway. + */ + for (block = 0; block < nftl->EraseSize / 512 ; block++) { + if (BlockLastState[block] != SECTOR_FREE && + BlockMap[block] != BLOCK_NIL && + BlockMap[block] != targetEUN) { + pr_debug("Setting inplace to 0. VUC %d, " + "block %d was %x lastEUN, " + "and is in EUN %d (%s) %d\n", + thisVUC, block, BlockLastState[block], + BlockMap[block], + BlockMap[block]== targetEUN ? "==" : "!=", + targetEUN); + inplace = 0; + break; + } + } + + if (pendingblock >= (thisVUC * (nftl->EraseSize / 512)) && + pendingblock < ((thisVUC + 1)* (nftl->EraseSize / 512)) && + BlockLastState[pendingblock - (thisVUC * (nftl->EraseSize / 512))] != + SECTOR_FREE) { + pr_debug("Pending write not free in EUN %d. " + "Folding out of place.\n", targetEUN); + inplace = 0; + } + } + + if (!inplace) { + pr_debug("Cannot fold Virtual Unit Chain %d in place. " + "Trying out-of-place\n", thisVUC); + /* We need to find a targetEUN to fold into. */ + targetEUN = NFTL_findfreeblock(nftl, 1); + if (targetEUN == BLOCK_NIL) { + /* Ouch. Now we're screwed. We need to do a + fold-in-place of another chain to make room + for this one. We need a better way of selecting + which chain to fold, because makefreeblock will + only ask us to fold the same one again. + */ + printk(KERN_WARNING + "NFTL_findfreeblock(desperate) returns 0xffff.\n"); + return BLOCK_NIL; + } + } else { + /* We put a fold mark in the chain we are folding only if we + fold in place to help the mount check code. If we do not fold in + place, it is possible to find the valid chain by selecting the + longer one */ + oob.u.c.FoldMark = oob.u.c.FoldMark1 = cpu_to_le16(FOLD_MARK_IN_PROGRESS); + oob.u.c.unused = 0xffffffff; + nftl_write_oob(mtd, (nftl->EraseSize * targetEUN) + 2 * 512 + 8, + 8, &retlen, (char *)&oob.u); + } + + /* OK. We now know the location of every block in the Virtual Unit Chain, + and the Erase Unit into which we are supposed to be copying. + Go for it. + */ + pr_debug("Folding chain %d into unit %d\n", thisVUC, targetEUN); + for (block = 0; block < nftl->EraseSize / 512 ; block++) { + unsigned char movebuf[512]; + int ret; + + /* If it's in the target EUN already, or if it's pending write, do nothing */ + if (BlockMap[block] == targetEUN || + (pendingblock == (thisVUC * (nftl->EraseSize / 512) + block))) { + continue; + } + + /* copy only in non free block (free blocks can only + happen in case of media errors or deleted blocks) */ + if (BlockMap[block] == BLOCK_NIL) + continue; + + ret = mtd_read(mtd, + (nftl->EraseSize * BlockMap[block]) + (block * 512), + 512, + &retlen, + movebuf); + if (ret < 0 && !mtd_is_bitflip(ret)) { + ret = mtd_read(mtd, + (nftl->EraseSize * BlockMap[block]) + (block * 512), + 512, + &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"); + lastEUN = BLOCK_NIL; + 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, +}; + +static int __init init_nftl(void) +{ + return register_mtd_blktrans(&nftl_tr); +} + +static void __exit cleanup_nftl(void) +{ + deregister_mtd_blktrans(&nftl_tr); +} + +module_init(init_nftl); +module_exit(cleanup_nftl); + +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); |