/* * inftlcore.c -- Linux driver for Inverse Flash Translation Layer (INFTL) * * Copyright © 2002, Greg Ungerer (gerg@snapgear.com) * * Based heavily on the nftlcore.c code which is: * Copyright © 1999 Machine Vision Holdings, Inc. * Copyright © 1999 David Woodhouse * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * 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 inftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) { struct INFTLrecord *inftl; unsigned long temp; if (mtd->type != MTD_NANDFLASH || mtd->size > UINT_MAX) return; /* OK, this is moderately ugly. But probably safe. Alternatives? */ if (memcmp(mtd->name, "DiskOnChip", 10)) return; if (!mtd->_block_isbad) { printk(KERN_ERR "INFTL no longer supports the old DiskOnChip drivers loaded via docprobe.\n" "Please use the new diskonchip driver under the NAND subsystem.\n"); return; } pr_debug("INFTL: add_mtd for %s\n", mtd->name); inftl = kzalloc(sizeof(*inftl), GFP_KERNEL); if (!inftl) return; inftl->mbd.mtd = mtd; inftl->mbd.devnum = -1; inftl->mbd.tr = tr; if (INFTL_mount(inftl) < 0) { printk(KERN_WARNING "INFTL: could not mount device\n"); kfree(inftl); return; } /* OK, it's a new one. Set up all the data structures. */ /* Calculate geometry */ inftl->cylinders = 1024; inftl->heads = 16; temp = inftl->cylinders * inftl->heads; inftl->sectors = inftl->mbd.size / temp; if (inftl->mbd.size % temp) { inftl->sectors++; temp = inftl->cylinders * inftl->sectors; inftl->heads = inftl->mbd.size / temp; if (inftl->mbd.size % temp) { inftl->heads++; temp = inftl->heads * inftl->sectors; inftl->cylinders = inftl->mbd.size / temp; } } if (inftl->mbd.size != inftl->heads * inftl->cylinders * inftl->sectors) { /* Oh no we don't have mbd.size == heads * cylinders * sectors */ printk(KERN_WARNING "INFTL: cannot calculate a geometry to " "match size of 0x%lx.\n", inftl->mbd.size); printk(KERN_WARNING "INFTL: using C:%d H:%d S:%d " "(== 0x%lx sects)\n", inftl->cylinders, inftl->heads , inftl->sectors, (long)inftl->cylinders * (long)inftl->heads * (long)inftl->sectors ); } if (add_mtd_blktrans_dev(&inftl->mbd)) { kfree(inftl->PUtable); kfree(inftl->VUtable); kfree(inftl); return; } #ifdef PSYCHO_DEBUG printk(KERN_INFO "INFTL: Found new inftl%c\n", inftl->mbd.devnum + 'a'); #endif return; } static void inftl_remove_dev(struct mtd_blktrans_dev *dev) { struct INFTLrecord *inftl = (void *)dev; pr_debug("INFTL: remove_dev (i=%d)\n", dev->devnum); del_mtd_blktrans_dev(dev); kfree(inftl->PUtable); kfree(inftl->VUtable); } /* * Actual INFTL access routines. */ /* * Read oob data from flash */ int inftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { struct mtd_oob_ops ops; int res; ops.mode = MTD_OPS_PLACE_OOB; ops.ooboffs = offs & (mtd->writesize - 1); ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; res = mtd_read_oob(mtd, offs & ~(mtd->writesize - 1), &ops); *retlen = ops.oobretlen; return res; } /* * Write oob data to flash */ int inftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf) { struct mtd_oob_ops ops; int res; ops.mode = MTD_OPS_PLACE_OOB; ops.ooboffs = offs & (mtd->writesize - 1); ops.ooblen = len; ops.oobbuf = buf; ops.datbuf = NULL; res = mtd_write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); *retlen = ops.oobretlen; return res; } /* * Write data and oob to flash */ static int inftl_write(struct mtd_info *mtd, loff_t offs, size_t len, size_t *retlen, uint8_t *buf, uint8_t *oob) { struct mtd_oob_ops ops; int res; ops.mode = MTD_OPS_PLACE_OOB; ops.ooboffs = offs; ops.ooblen = mtd->oobsize; ops.oobbuf = oob; ops.datbuf = buf; ops.len = len; res = mtd_write_oob(mtd, offs & ~(mtd->writesize - 1), &ops); *retlen = ops.retlen; return res; } /* * INFTL_findfreeblock: Find a free Erase Unit on the INFTL partition. * This function is used when the give Virtual Unit Chain. */ static u16 INFTL_findfreeblock(struct INFTLrecord *inftl, int desperate) { u16 pot = inftl->LastFreeEUN; int silly = inftl->nb_blocks; pr_debug("INFTL: INFTL_findfreeblock(inftl=%p,desperate=%d)\n", inftl, desperate); /* * Normally, we force a fold to happen before we run out of free * blocks completely. */ if (!desperate && inftl->numfreeEUNs < 2) { pr_debug("INFTL: there are too few free EUNs (%d)\n", inftl->numfreeEUNs); return BLOCK_NIL; } /* Scan for a free block */ do { if (inftl->PUtable[pot] == BLOCK_FREE) { inftl->LastFreeEUN = pot; return pot; } if (++pot > inftl->lastEUN) pot = 0; if (!silly--) { printk(KERN_WARNING "INFTL: no free blocks found! " "EUN range = %d - %d\n", 0, inftl->LastFreeEUN); return BLOCK_NIL; } } while (pot != inftl->LastFreeEUN); return BLOCK_NIL; } static u16 INFTL_foldchain(struct INFTLrecord *inftl, unsigned thisVUC, unsigned pendingblock) { u16 BlockMap[MAX_SECTORS_PER_UNIT]; unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT]; unsigned int thisEUN, prevEUN, status; struct mtd_info *mtd = inftl->mbd.mtd; int block, silly; unsigned int targetEUN; struct inftl_oob oob; size_t retlen; pr_debug("INFTL: INFTL_foldchain(inftl=%p,thisVUC=%d,pending=%d)\n", inftl, thisVUC, pendingblock); memset(BlockMap, 0xff, sizeof(BlockMap)); memset(BlockDeleted, 0, sizeof(BlockDeleted)); thisEUN = targetEUN = inftl->VUtable[thisVUC]; if (thisEUN == BLOCK_NIL) { printk(KERN_WARNING "INFTL: 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; while (thisEUN < inftl->nb_blocks) { for (block = 0; block < inftl->EraseSize/SECTORSIZE; block ++) { if ((BlockMap[block] != BLOCK_NIL) || BlockDeleted[block]) continue; if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) + (block * SECTORSIZE), 16, &retlen, (char *)&oob) < 0) status = SECTOR_IGNORE; else status = oob.b.Status | oob.b.Status1; switch(status) { case SECTOR_FREE: case SECTOR_IGNORE: break; case SECTOR_USED: BlockMap[block] = thisEUN; continue; case SECTOR_DELETED: BlockDeleted[block] = 1; continue; default: printk(KERN_WARNING "INFTL: unknown status " "for block %d in EUN %d: %x\n", block, thisEUN, status); break; } } if (!silly--) { printk(KERN_WARNING "INFTL: infinite loop in Virtual " "Unit Chain 0x%x\n", thisVUC); return BLOCK_NIL; } thisEUN = inftl->PUtable[thisEUN]; } /* * 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("INFTL: folding chain %d into unit %d\n", thisVUC, targetEUN); for (block = 0; block < inftl->EraseSize/SECTORSIZE ; block++) { unsigned char movebuf[SECTORSIZE]; int ret; /* * If it's in the target EUN already, or if it's pending write, * do nothing. */ if (BlockMap[block] == targetEUN || (pendingblock == (thisVUC * (inftl->EraseSize / SECTORSIZE) + 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, (inftl->EraseSize * BlockMap[block]) + (block * SECTORSIZE), SECTORSIZE, &retlen, movebuf); if (ret < 0 && !mtd_is_bitflip(ret)) { ret = mtd_read(mtd, (inftl->EraseSize * BlockMap[block]) + (block * SECTORSIZE), SECTORSIZE, &retlen, movebuf); if (ret != -EIO) pr_debug("INFTL: error went away on retry?\n"); } memset(&oob, 0xff, sizeof(struct inftl_oob)); oob.b.Status = oob.b.Status1 = SECTOR_USED; inftl_write(inftl->mbd.mtd, (inftl->EraseSize * targetEUN) + (block * SECTORSIZE), SECTORSIZE, &retlen, movebuf, (char *)&oob); } /* * Newest unit in chain now contains data from _all_ older units. * So go through and erase each unit in chain, oldest first. (This * is important, by doing oldest first if we crash/reboot then it * it is relatively simple to clean up the mess). */ pr_debug("INFTL: want to erase virtual chain %d\n", thisVUC); for (;;) { /* Find oldest unit in chain. */ thisEUN = inftl->VUtable[thisVUC]; prevEUN = BLOCK_NIL; while (inftl->PUtable[thisEUN] != BLOCK_NIL) { prevEUN = thisEUN; thisEUN = inftl->PUtable[thisEUN]; } /* Check if we are all done */ if (thisEUN == targetEUN) break; /* Unlink the last block from the chain. */ inftl->PUtable[prevEUN] = BLOCK_NIL; /* Now try to erase it. */ if (INFTL_formatblock(inftl, thisEUN) < 0) { /* * Could not erase : mark block as reserved. */ inftl->PUtable[thisEUN] = BLOCK_RESERVED; } else { /* Correctly erased : mark it as free */ inftl->PUtable[thisEUN] = BLOCK_FREE; inftl->numfreeEUNs++; } } return targetEUN; } static u16 INFTL_makefreeblock(struct INFTLrecord *inftl, 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; pr_debug("INFTL: INFTL_makefreeblock(inftl=%p," "pending=%d)\n", inftl, pendingblock); for (chain = 0; chain < inftl->nb_blocks; chain++) { EUN = inftl->VUtable[chain]; thislen = 0; while (EUN <= inftl->lastEUN) { thislen++; EUN = inftl->PUtable[EUN]; if (thislen > 0xff00) { printk(KERN_WARNING "INFTL: endless loop in " "Virtual Chain %d: Unit %x\n", chain, EUN); /* * Actually, don't return failure. * Just ignore this chain and get on with it. */ thislen = 0; break; } } if (thislen > ChainLength) { ChainLength = thislen; LongestChain = chain; } } if (ChainLength < 2) { printk(KERN_WARNING "INFTL: no Virtual Unit Chains available " "for folding. Failing request\n"); return BLOCK_NIL; } return INFTL_foldchain(inftl, LongestChain, pendingblock); } static int nrbits(unsigned int val, int bitcount) { int i, total = 0; for (i = 0; (i < bitcount); i++) total += (((0x1 << i) & val) ? 1 : 0); return total; } /* * INFTL_findwriteunit: Return the unit number into which we can write * for this block. Make it available if it isn't already. */ static inline u16 INFTL_findwriteunit(struct INFTLrecord *inftl, unsigned block) { unsigned int thisVUC = block / (inftl->EraseSize / SECTORSIZE); unsigned int thisEUN, writeEUN, prev_block, status; unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize -1); struct mtd_info *mtd = inftl->mbd.mtd; struct inftl_oob oob; struct inftl_bci bci; unsigned char anac, nacs, parity; size_t retlen; int silly, silly2 = 3; pr_debug("INFTL: INFTL_findwriteunit(inftl=%p,block=%d)\n", inftl, block); do { /* * Scan the media to find a unit in the VUC which has * a free space for the block in question. */ writeEUN = BLOCK_NIL; thisEUN = inftl->VUtable[thisVUC]; silly = MAX_LOOPS; while (thisEUN <= inftl->lastEUN) { inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) + blockofs, 8, &retlen, (char *)&bci); status = bci.Status | bci.Status1; pr_debug("INFTL: status of block %d in EUN %d is %x\n", block , writeEUN, status); switch(status) { case SECTOR_FREE: writeEUN = thisEUN; break; case SECTOR_DELETED: case SECTOR_USED: /* Can't go any further */ goto hitused; case SECTOR_IGNORE: break; default: /* * Invalid block. Don't use it any more. * Must implement. */ break; } if (!silly--) { printk(KERN_WARNING "INFTL: infinite loop in " "Virtual Unit Chain 0x%x\n", thisVUC); return BLOCK_NIL; } /* Skip to next block in chain */ thisEUN = inftl->PUtable[thisEUN]; } hitused: if (writeEUN != BLOCK_NIL) return writeEUN; /* * OK. We didn't find one in the existing chain, or there * is no existing chain. Allocate a new one. */ writeEUN = INFTL_findfreeblock(inftl, 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. */ thisEUN = INFTL_makefreeblock(inftl, block); /* * Hopefully we free something, lets try again. * This time we are desperate... */ pr_debug("INFTL: using desperate==1 to find free EUN " "to accommodate write to VUC %d\n", thisVUC); writeEUN = INFTL_findfreeblock(inftl, 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 "INFTL: cannot make free " "space.\n"); #ifdef DEBUG INFTL_dumptables(inftl); INFTL_dumpVUchains(inftl); #endif return BLOCK_NIL; } } /* * Insert new block into virtual chain. Firstly update the * block headers in flash... */ anac = 0; nacs = 0; thisEUN = inftl->VUtable[thisVUC]; if (thisEUN != BLOCK_NIL) { inftl_read_oob(mtd, thisEUN * inftl->EraseSize + 8, 8, &retlen, (char *)&oob.u); anac = oob.u.a.ANAC + 1; nacs = oob.u.a.NACs + 1; } prev_block = inftl->VUtable[thisVUC]; if (prev_block < inftl->nb_blocks) prev_block -= inftl->firstEUN; parity = (nrbits(thisVUC, 16) & 0x1) ? 0x1 : 0; parity |= (nrbits(prev_block, 16) & 0x1) ? 0x2 : 0; parity |= (nrbits(anac, 8) & 0x1) ? 0x4 : 0; parity |= (nrbits(nacs, 8) & 0x1) ? 0x8 : 0; oob.u.a.virtualUnitNo = cpu_to_le16(thisVUC); oob.u.a.prevUnitNo = cpu_to_le16(prev_block); oob.u.a.ANAC = anac; oob.u.a.NACs = nacs; oob.u.a.parityPerField = parity; oob.u.a.discarded = 0xaa; inftl_write_oob(mtd, writeEUN * inftl->EraseSize + 8, 8, &retlen, (char *)&oob.u); /* Also back up header... */ oob.u.b.virtualUnitNo = cpu_to_le16(thisVUC); oob.u.b.prevUnitNo = cpu_to_le16(prev_block); oob.u.b.ANAC = anac; oob.u.b.NACs = nacs; oob.u.b.parityPerField = parity; oob.u.b.discarded = 0xaa; inftl_write_oob(mtd, writeEUN * inftl->EraseSize + SECTORSIZE * 4 + 8, 8, &retlen, (char *)&oob.u); inftl->PUtable[writeEUN] = inftl->VUtable[thisVUC]; inftl->VUtable[thisVUC] = writeEUN; inftl->numfreeEUNs--; return writeEUN; } while (silly2--); printk(KERN_WARNING "INFTL: error folding to make room for Virtual " "Unit Chain 0x%x\n", thisVUC); return BLOCK_NIL; } /* * Given a Virtual Unit Chain, see if it can be deleted, and if so do it. */ static void INFTL_trydeletechain(struct INFTLrecord *inftl, unsigned thisVUC) { struct mtd_info *mtd = inftl->mbd.mtd; unsigned char BlockUsed[MAX_SECTORS_PER_UNIT]; unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT]; unsigned int thisEUN, status; int block, silly; struct inftl_bci bci; size_t retlen; pr_debug("INFTL: INFTL_trydeletechain(inftl=%p," "thisVUC=%d)\n", inftl, thisVUC); memset(BlockUsed, 0, sizeof(BlockUsed)); memset(BlockDeleted, 0, sizeof(BlockDeleted)); thisEUN = inftl->VUtable[thisVUC]; if (thisEUN == BLOCK_NIL) { printk(KERN_WARNING "INFTL: trying to delete non-existent " "Virtual Unit Chain %d!\n", thisVUC); return; } /* * Scan through the Erase Units to determine whether any data is in * each of the 512-byte blocks within the Chain. */ silly = MAX_LOOPS; while (thisEUN < inftl->nb_blocks) { for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++) { if (BlockUsed[block] || BlockDeleted[block]) continue; if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) + (block * SECTORSIZE), 8 , &retlen, (char *)&bci) < 0) status = SECTOR_IGNORE; else status = bci.Status | bci.Status1; switch(status) { case SECTOR_FREE: case SECTOR_IGNORE: break; case SECTOR_USED: BlockUsed[block] = 1; continue; case SECTOR_DELETED: BlockDeleted[block] = 1; continue; default: printk(KERN_WARNING "INFTL: unknown status " "for block %d in EUN %d: 0x%x\n", block, thisEUN, status); } } if (!silly--) { printk(KERN_WARNING "INFTL: infinite loop in Virtual " "Unit Chain 0x%x\n", thisVUC); return; } thisEUN = inftl->PUtable[thisEUN]; } for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++) if (BlockUsed[block]) return; /* * For each block in the chain free it and make it available * for future use. Erase from the oldest unit first. */ pr_debug("INFTL: deleting empty VUC %d\n", thisVUC); for (;;) { u16 *prevEUN = &inftl->VUtable[thisVUC]; thisEUN = *prevEUN; /* If the chain is all gone already, we're done */ if (thisEUN == BLOCK_NIL) { pr_debug("INFTL: Empty VUC %d for deletion was already absent\n", thisEUN); return; } /* Find oldest unit in chain. */ while (inftl->PUtable[thisEUN] != BLOCK_NIL) { BUG_ON(thisEUN >= inftl->nb_blocks); prevEUN = &inftl->PUtable[thisEUN]; thisEUN = *prevEUN; } pr_debug("Deleting EUN %d from VUC %d\n", thisEUN, thisVUC); if (INFTL_formatblock(inftl, thisEUN) < 0) { /* * Could not erase : mark block as reserved. */ inftl->PUtable[thisEUN] = BLOCK_RESERVED; } else { /* Correctly erased : mark it as free */ inftl->PUtable[thisEUN] = BLOCK_FREE; inftl->numfreeEUNs++; } /* Now sort out whatever was pointing to it... */ *prevEUN = BLOCK_NIL; /* Ideally we'd actually be responsive to new requests while we're doing this -- if there's free space why should others be made to wait? */ cond_resched(); } inftl->VUtable[thisVUC] = BLOCK_NIL; } static int INFTL_deleteblock(struct INFTLrecord *inftl, unsigned block) { unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)]; unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); struct mtd_info *mtd = inftl->mbd.mtd; unsigned int status; int silly = MAX_LOOPS; size_t retlen; struct inftl_bci bci; pr_debug("INFTL: INFTL_deleteblock(inftl=%p," "block=%d)\n", inftl, block); while (thisEUN < inftl->nb_blocks) { if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) + blockofs, 8, &retlen, (char *)&bci) < 0) status = SECTOR_IGNORE; else status = bci.Status | bci.Status1; switch (status) { case SECTOR_FREE: case SECTOR_IGNORE: break; case SECTOR_DELETED: thisEUN = BLOCK_NIL; goto foundit; case SECTOR_USED: goto foundit; default: printk(KERN_WARNING "INFTL: unknown status for " "block %d in EUN %d: 0x%x\n", block, thisEUN, status); break; } if (!silly--) { printk(KERN_WARNING "INFTL: infinite loop in Virtual " "Unit Chain 0x%x\n", block / (inftl->EraseSize / SECTORSIZE)); return 1; } thisEUN = inftl->PUtable[thisEUN]; } foundit: if (thisEUN != BLOCK_NIL) { loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs; if (inftl_read_oob(mtd, ptr, 8, &retlen, (char *)&bci) < 0) return -EIO; bci.Status = bci.Status1 = SECTOR_DELETED; if (inftl_write_oob(mtd, ptr, 8, &retlen, (char *)&bci) < 0) return -EIO; INFTL_trydeletechain(inftl, block / (inftl->EraseSize / SECTORSIZE)); } return 0; } static int inftl_writeblock(struct mtd_blktrans_dev *mbd, unsigned long block, char *buffer) { struct INFTLrecord *inftl = (void *)mbd; unsigned int writeEUN; unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); size_t retlen; struct inftl_oob oob; char *p, *pend; pr_debug("INFTL: inftl_writeblock(inftl=%p,block=%ld," "buffer=%p)\n", inftl, block, buffer); /* Is block all zero? */ pend = buffer + SECTORSIZE; for (p = buffer; p < pend && !*p; p++) ; if (p < pend) { writeEUN = INFTL_findwriteunit(inftl, block); if (writeEUN == BLOCK_NIL) { printk(KERN_WARNING "inftl_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 inftl_oob)); oob.b.Status = oob.b.Status1 = SECTOR_USED; inftl_write(inftl->mbd.mtd, (writeEUN * inftl->EraseSize) + blockofs, SECTORSIZE, &retlen, (char *)buffer, (char *)&oob); /* * need to write SECTOR_USED flags since they are not written * in mtd_writeecc */ } else { INFTL_deleteblock(inftl, block); } return 0; } static int inftl_readblock(struct mtd_blktrans_dev *mbd, unsigned long block, char *buffer) { struct INFTLrecord *inftl = (void *)mbd; unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)]; unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); struct mtd_info *mtd = inftl->mbd.mtd; unsigned int status; int silly = MAX_LOOPS; struct inftl_bci bci; size_t retlen; pr_debug("INFTL: inftl_readblock(inftl=%p,block=%ld," "buffer=%p)\n", inftl, block, buffer); while (thisEUN < inftl->nb_blocks) { if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) + blockofs, 8, &retlen, (char *)&bci) < 0) status = SECTOR_IGNORE; else status = bci.Status | bci.Status1; switch (status) { case SECTOR_DELETED: thisEUN = BLOCK_NIL; goto foundit; case SECTOR_USED: goto foundit; case SECTOR_FREE: case SECTOR_IGNORE: break; default: printk(KERN_WARNING "INFTL: unknown status for " "block %ld in EUN %d: 0x%04x\n", block, thisEUN, status); break; } if (!silly--) { printk(KERN_WARNING "INFTL: infinite loop in " "Virtual Unit Chain 0x%lx\n", block / (inftl->EraseSize / SECTORSIZE)); return 1; } thisEUN = inftl->PUtable[thisEUN]; } foundit: if (thisEUN == BLOCK_NIL) { /* The requested block is not on the media, return all 0x00 */ memset(buffer, 0, SECTORSIZE); } else { size_t retlen; loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs; int ret = mtd_read(mtd, ptr, SECTORSIZE, &retlen, buffer); /* Handle corrected bit flips gracefully */ if (ret < 0 && !mtd_is_bitflip(ret)) return -EIO; } return 0; } static int inftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) { struct INFTLrecord *inftl = (void *)dev; geo->heads = inftl->heads; geo->sectors = inftl->sectors; geo->cylinders = inftl->cylinders; return 0; } static struct mtd_blktrans_ops inftl_tr = { .name = "inftl", .major = INFTL_MAJOR, .part_bits = INFTL_PARTN_BITS, .blksize = 512, .getgeo = inftl_getgeo, .readsect = inftl_readblock, .writesect = inftl_writeblock, .add_mtd = inftl_add_mtd, .remove_dev = inftl_remove_dev, .owner = THIS_MODULE, }; static int __init init_inftl(void) { return register_mtd_blktrans(&inftl_tr); } static void __exit cleanup_inftl(void) { deregister_mtd_blktrans(&inftl_tr); } module_init(init_inftl); module_exit(cleanup_inftl); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Greg Ungerer , David Woodhouse , Fabrice Bellard et al."); MODULE_DESCRIPTION("Support code for Inverse Flash Translation Layer, used on M-Systems DiskOnChip 2000, Millennium and Millennium Plus");