| /* |
| * 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/nand.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 + |
| SECTORSIZE + 8, 8, &retlen, |
| (char *)&h1); |
| if (ret < 0) { |
| printk(KERN_WARNING "ANAND header found at 0x%x in mtd%d, but OOB data read failed (err %d)\n", |
| block * nftl->EraseSize, nftl->mbd.mtd->index, ret); |
| continue; |
| } |
| |
| #if 0 /* Some people seem to have devices without ECC or erase marks |
| on the Media Header blocks. There are enough other sanity |
| checks in here that we can probably do without it. |
| */ |
| if (le16_to_cpu(h1.EraseMark | h1.EraseMark1) != ERASE_MARK) { |
| printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but erase mark not present (0x%04x,0x%04x instead)\n", |
| block * nftl->EraseSize, nftl->mbd.mtd->index, |
| le16_to_cpu(h1.EraseMark), le16_to_cpu(h1.EraseMark1)); |
| continue; |
| } |
| |
| /* Finally reread to check ECC */ |
| ret = mtd->read(mtd, block * nftl->EraseSize, SECTORSIZE, |
| &retlen, buf); |
| if (ret < 0) { |
| printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but ECC read failed (err %d)\n", |
| block * nftl->EraseSize, nftl->mbd.mtd->index, ret); |
| continue; |
| } |
| |
| /* Paranoia. Check the ANAND header is still there after the ECC read */ |
| if (memcmp(buf, "ANAND", 6)) { |
| printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but went away on reread!\n", |
| block * nftl->EraseSize, nftl->mbd.mtd->index); |
| printk(KERN_NOTICE "New data are: %02x %02x %02x %02x %02x %02x\n", |
| buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]); |
| continue; |
| } |
| #endif |
| /* OK, we like it. */ |
| |
| if (boot_record_count) { |
| /* We've already processed one. So we just check if |
| this one is the same as the first one we found */ |
| if (memcmp(mh, buf, sizeof(struct NFTLMediaHeader))) { |
| printk(KERN_NOTICE "NFTL Media Headers at 0x%x and 0x%x disagree.\n", |
| nftl->MediaUnit * nftl->EraseSize, block * nftl->EraseSize); |
| /* if (debug) Print both side by side */ |
| if (boot_record_count < 2) { |
| /* We haven't yet seen two real ones */ |
| return -1; |
| } |
| continue; |
| } |
| if (boot_record_count == 1) |
| nftl->SpareMediaUnit = block; |
| |
| /* Mark this boot record (NFTL MediaHeader) block as reserved */ |
| nftl->ReplUnitTable[block] = BLOCK_RESERVED; |
| |
| |
| boot_record_count++; |
| continue; |
| } |
| |
| /* This is the first we've seen. Copy the media header structure into place */ |
| memcpy(mh, buf, sizeof(struct NFTLMediaHeader)); |
| |
| /* Do some sanity checks on it */ |
| #if 0 |
| The new DiskOnChip driver scans the MediaHeader itself, and presents a virtual |
| erasesize based on UnitSizeFactor. So the erasesize we read from the mtd |
| device is already correct. |
| if (mh->UnitSizeFactor == 0) { |
| printk(KERN_NOTICE "NFTL: UnitSizeFactor 0x00 detected. This violates the spec but we think we know what it means...\n"); |
| } else if (mh->UnitSizeFactor < 0xfc) { |
| printk(KERN_NOTICE "Sorry, we don't support UnitSizeFactor 0x%02x\n", |
| mh->UnitSizeFactor); |
| return -1; |
| } else if (mh->UnitSizeFactor != 0xff) { |
| printk(KERN_NOTICE "WARNING: Support for NFTL with UnitSizeFactor 0x%02x is experimental\n", |
| mh->UnitSizeFactor); |
| nftl->EraseSize = nftl->mbd.mtd->erasesize << (0xff - mh->UnitSizeFactor); |
| nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize; |
| } |
| #endif |
| nftl->nb_boot_blocks = le16_to_cpu(mh->FirstPhysicalEUN); |
| if ((nftl->nb_boot_blocks + 2) >= nftl->nb_blocks) { |
| printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); |
| printk(KERN_NOTICE "nb_boot_blocks (%d) + 2 > nb_blocks (%d)\n", |
| nftl->nb_boot_blocks, nftl->nb_blocks); |
| return -1; |
| } |
| |
| nftl->numvunits = le32_to_cpu(mh->FormattedSize) / nftl->EraseSize; |
| if (nftl->numvunits > (nftl->nb_blocks - nftl->nb_boot_blocks - 2)) { |
| printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); |
| printk(KERN_NOTICE "numvunits (%d) > nb_blocks (%d) - nb_boot_blocks(%d) - 2\n", |
| nftl->numvunits, nftl->nb_blocks, nftl->nb_boot_blocks); |
| return -1; |
| } |
| |
| nftl->mbd.size = nftl->numvunits * (nftl->EraseSize / SECTORSIZE); |
| |
| /* If we're not using the last sectors in the device for some reason, |
| reduce nb_blocks accordingly so we forget they're there */ |
| nftl->nb_blocks = le16_to_cpu(mh->NumEraseUnits) + le16_to_cpu(mh->FirstPhysicalEUN); |
| |
| /* XXX: will be suppressed */ |
| nftl->lastEUN = nftl->nb_blocks - 1; |
| |
| /* memory alloc */ |
| nftl->EUNtable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL); |
| if (!nftl->EUNtable) { |
| printk(KERN_NOTICE "NFTL: allocation of EUNtable failed\n"); |
| return -ENOMEM; |
| } |
| |
| nftl->ReplUnitTable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL); |
| if (!nftl->ReplUnitTable) { |
| kfree(nftl->EUNtable); |
| printk(KERN_NOTICE "NFTL: allocation of ReplUnitTable failed\n"); |
| return -ENOMEM; |
| } |
| |
| /* mark the bios blocks (blocks before NFTL MediaHeader) as reserved */ |
| for (i = 0; i < nftl->nb_boot_blocks; i++) |
| nftl->ReplUnitTable[i] = BLOCK_RESERVED; |
| /* mark all remaining blocks as potentially containing data */ |
| for (; i < nftl->nb_blocks; i++) { |
| nftl->ReplUnitTable[i] = BLOCK_NOTEXPLORED; |
| } |
| |
| /* Mark this boot record (NFTL MediaHeader) block as reserved */ |
| nftl->ReplUnitTable[block] = BLOCK_RESERVED; |
| |
| /* read the Bad Erase Unit Table and modify ReplUnitTable[] accordingly */ |
| for (i = 0; i < nftl->nb_blocks; i++) { |
| #if 0 |
| The new DiskOnChip driver already scanned the bad block table. Just query it. |
| if ((i & (SECTORSIZE - 1)) == 0) { |
| /* read one sector for every SECTORSIZE of blocks */ |
| ret = mtd->read(nftl->mbd.mtd, |
| block * nftl->EraseSize + i + |
| SECTORSIZE, SECTORSIZE, |
| &retlen, buf); |
| if (ret < 0) { |
| printk(KERN_NOTICE "Read of bad sector table failed (err %d)\n", |
| ret); |
| kfree(nftl->ReplUnitTable); |
| kfree(nftl->EUNtable); |
| return -1; |
| } |
| } |
| /* mark the Bad Erase Unit as RESERVED in ReplUnitTable */ |
| if (buf[i & (SECTORSIZE - 1)] != 0xff) |
| nftl->ReplUnitTable[i] = BLOCK_RESERVED; |
| #endif |
| if (mtd_block_isbad(nftl->mbd.mtd, |
| i * nftl->EraseSize)) |
| nftl->ReplUnitTable[i] = BLOCK_RESERVED; |
| } |
| |
| nftl->MediaUnit = block; |
| boot_record_count++; |
| |
| } /* foreach (block) */ |
| |
| return boot_record_count?0:-1; |
| } |
| |
| static int memcmpb(void *a, int c, int n) |
| { |
| int i; |
| for (i = 0; i < n; i++) { |
| if (c != ((unsigned char *)a)[i]) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* check_free_sector: check if a free sector is actually FREE, i.e. All 0xff in data and oob area */ |
| static int check_free_sectors(struct NFTLrecord *nftl, unsigned int address, int len, |
| int check_oob) |
| { |
| u8 buf[SECTORSIZE + nftl->mbd.mtd->oobsize]; |
| struct mtd_info *mtd = nftl->mbd.mtd; |
| size_t retlen; |
| int i; |
| |
| for (i = 0; i < len; i += SECTORSIZE) { |
| if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf)) |
| return -1; |
| if (memcmpb(buf, 0xff, SECTORSIZE) != 0) |
| return -1; |
| |
| if (check_oob) { |
| if(nftl_read_oob(mtd, address, mtd->oobsize, |
| &retlen, &buf[SECTORSIZE]) < 0) |
| return -1; |
| if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0) |
| return -1; |
| } |
| address += SECTORSIZE; |
| } |
| |
| return 0; |
| } |
| |
| /* NFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase Unit and |
| * Update NFTL metadata. Each erase operation is checked with check_free_sectors |
| * |
| * Return: 0 when succeed, -1 on error. |
| * |
| * ToDo: 1. Is it necessary to check_free_sector after erasing ?? |
| */ |
| int NFTL_formatblock(struct NFTLrecord *nftl, int block) |
| { |
| size_t retlen; |
| unsigned int nb_erases, erase_mark; |
| struct nftl_uci1 uci; |
| struct erase_info *instr = &nftl->instr; |
| struct mtd_info *mtd = nftl->mbd.mtd; |
| |
| /* Read the Unit Control Information #1 for Wear-Leveling */ |
| if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, |
| 8, &retlen, (char *)&uci) < 0) |
| goto default_uci1; |
| |
| erase_mark = le16_to_cpu ((uci.EraseMark | uci.EraseMark1)); |
| if (erase_mark != ERASE_MARK) { |
| default_uci1: |
| uci.EraseMark = cpu_to_le16(ERASE_MARK); |
| uci.EraseMark1 = cpu_to_le16(ERASE_MARK); |
| uci.WearInfo = cpu_to_le32(0); |
| } |
| |
| memset(instr, 0, sizeof(struct erase_info)); |
| |
| /* XXX: use async erase interface, XXX: test return code */ |
| instr->mtd = nftl->mbd.mtd; |
| instr->addr = block * nftl->EraseSize; |
| instr->len = nftl->EraseSize; |
| mtd_erase(mtd, instr); |
| |
| if (instr->state == MTD_ERASE_FAILED) { |
| printk("Error while formatting block %d\n", block); |
| goto fail; |
| } |
| |
| /* increase and write Wear-Leveling info */ |
| nb_erases = le32_to_cpu(uci.WearInfo); |
| nb_erases++; |
| |
| /* wrap (almost impossible with current flash) or free block */ |
| if (nb_erases == 0) |
| nb_erases = 1; |
| |
| /* check the "freeness" of Erase Unit before updating metadata |
| * FixMe: is this check really necessary ? since we have check the |
| * return code after the erase operation. */ |
| if (check_free_sectors(nftl, instr->addr, nftl->EraseSize, 1) != 0) |
| goto fail; |
| |
| uci.WearInfo = le32_to_cpu(nb_erases); |
| if (nftl_write_oob(mtd, block * nftl->EraseSize + SECTORSIZE + |
| 8, 8, &retlen, (char *)&uci) < 0) |
| goto fail; |
| return 0; |
| fail: |
| /* could not format, update the bad block table (caller is responsible |
| for setting the ReplUnitTable to BLOCK_RESERVED on failure) */ |
| mtd_block_markbad(nftl->mbd.mtd, instr->addr); |
| return -1; |
| } |
| |
| /* check_sectors_in_chain: Check that each sector of a Virtual Unit Chain is correct. |
| * Mark as 'IGNORE' each incorrect sector. This check is only done if the chain |
| * was being folded when NFTL was interrupted. |
| * |
| * The check_free_sectors in this function is necessary. There is a possible |
| * situation that after writing the Data area, the Block Control Information is |
| * not updated according (due to power failure or something) which leaves the block |
| * in an inconsistent state. So we have to check if a block is really FREE in this |
| * case. */ |
| static void check_sectors_in_chain(struct NFTLrecord *nftl, unsigned int first_block) |
| { |
| struct mtd_info *mtd = nftl->mbd.mtd; |
| unsigned int block, i, status; |
| struct nftl_bci bci; |
| int sectors_per_block; |
| size_t retlen; |
| |
| sectors_per_block = nftl->EraseSize / SECTORSIZE; |
| block = first_block; |
| for (;;) { |
| for (i = 0; i < sectors_per_block; i++) { |
| if (nftl_read_oob(mtd, |
| block * nftl->EraseSize + i * SECTORSIZE, |
| 8, &retlen, (char *)&bci) < 0) |
| status = SECTOR_IGNORE; |
| else |
| status = bci.Status | bci.Status1; |
| |
| switch(status) { |
| case SECTOR_FREE: |
| /* verify that the sector is really free. If not, mark |
| as ignore */ |
| if (memcmpb(&bci, 0xff, 8) != 0 || |
| check_free_sectors(nftl, block * nftl->EraseSize + i * SECTORSIZE, |
| SECTORSIZE, 0) != 0) { |
| printk("Incorrect free sector %d in block %d: " |
| "marking it as ignored\n", |
| i, block); |
| |
| /* sector not free actually : mark it as SECTOR_IGNORE */ |
| bci.Status = SECTOR_IGNORE; |
| bci.Status1 = SECTOR_IGNORE; |
| nftl_write_oob(mtd, block * |
| nftl->EraseSize + |
| i * SECTORSIZE, 8, |
| &retlen, (char *)&bci); |
| } |
| break; |
| default: |
| break; |
| } |
| } |
| |
| /* proceed to next Erase Unit on the chain */ |
| block = nftl->ReplUnitTable[block]; |
| if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) |
| printk("incorrect ReplUnitTable[] : %d\n", block); |
| if (block == BLOCK_NIL || block >= nftl->nb_blocks) |
| break; |
| } |
| } |
| |
| /* calc_chain_length: Walk through a Virtual Unit Chain and estimate chain length */ |
| static int calc_chain_length(struct NFTLrecord *nftl, unsigned int first_block) |
| { |
| unsigned int length = 0, block = first_block; |
| |
| for (;;) { |
| length++; |
| /* avoid infinite loops, although this is guaranteed not to |
| happen because of the previous checks */ |
| if (length >= nftl->nb_blocks) { |
| printk("nftl: length too long %d !\n", length); |
| break; |
| } |
| |
| block = nftl->ReplUnitTable[block]; |
| if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) |
| printk("incorrect ReplUnitTable[] : %d\n", block); |
| if (block == BLOCK_NIL || block >= nftl->nb_blocks) |
| break; |
| } |
| return length; |
| } |
| |
| /* format_chain: Format an invalid Virtual Unit chain. It frees all the Erase Units in a |
| * Virtual Unit Chain, i.e. all the units are disconnected. |
| * |
| * It is not strictly correct to begin from the first block of the chain because |
| * if we stop the code, we may see again a valid chain if there was a first_block |
| * flag in a block inside it. But is it really a problem ? |
| * |
| * FixMe: Figure out what the last statement means. What if power failure when we are |
| * in the for (;;) loop formatting blocks ?? |
| */ |
| static void format_chain(struct NFTLrecord *nftl, unsigned int first_block) |
| { |
| unsigned int block = first_block, block1; |
| |
| printk("Formatting chain at block %d\n", first_block); |
| |
| for (;;) { |
| block1 = nftl->ReplUnitTable[block]; |
| |
| printk("Formatting block %d\n", block); |
| if (NFTL_formatblock(nftl, block) < 0) { |
| /* cannot format !!!! Mark it as Bad Unit */ |
| nftl->ReplUnitTable[block] = BLOCK_RESERVED; |
| } else { |
| nftl->ReplUnitTable[block] = BLOCK_FREE; |
| } |
| |
| /* goto next block on the chain */ |
| block = block1; |
| |
| if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) |
| printk("incorrect ReplUnitTable[] : %d\n", block); |
| if (block == BLOCK_NIL || block >= nftl->nb_blocks) |
| break; |
| } |
| } |
| |
| /* check_and_mark_free_block: Verify that a block is free in the NFTL sense (valid erase mark) or |
| * totally free (only 0xff). |
| * |
| * Definition: Free Erase Unit -- A properly erased/formatted Free Erase Unit should have meet the |
| * following criteria: |
| * 1. */ |
| static int check_and_mark_free_block(struct NFTLrecord *nftl, int block) |
| { |
| struct mtd_info *mtd = nftl->mbd.mtd; |
| struct nftl_uci1 h1; |
| unsigned int erase_mark; |
| size_t retlen; |
| |
| /* check erase mark. */ |
| if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8, |
| &retlen, (char *)&h1) < 0) |
| return -1; |
| |
| erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1)); |
| if (erase_mark != ERASE_MARK) { |
| /* if no erase mark, the block must be totally free. This is |
| possible in two cases : empty filesystem or interrupted erase (very unlikely) */ |
| if (check_free_sectors (nftl, block * nftl->EraseSize, nftl->EraseSize, 1) != 0) |
| return -1; |
| |
| /* free block : write erase mark */ |
| h1.EraseMark = cpu_to_le16(ERASE_MARK); |
| h1.EraseMark1 = cpu_to_le16(ERASE_MARK); |
| h1.WearInfo = cpu_to_le32(0); |
| if (nftl_write_oob(mtd, |
| block * nftl->EraseSize + SECTORSIZE + 8, 8, |
| &retlen, (char *)&h1) < 0) |
| return -1; |
| } else { |
| #if 0 |
| /* if erase mark present, need to skip it when doing check */ |
| for (i = 0; i < nftl->EraseSize; i += SECTORSIZE) { |
| /* check free sector */ |
| if (check_free_sectors (nftl, block * nftl->EraseSize + i, |
| SECTORSIZE, 0) != 0) |
| return -1; |
| |
| if (nftl_read_oob(mtd, block * nftl->EraseSize + i, |
| 16, &retlen, buf) < 0) |
| return -1; |
| if (i == SECTORSIZE) { |
| /* skip erase mark */ |
| if (memcmpb(buf, 0xff, 8)) |
| return -1; |
| } else { |
| if (memcmpb(buf, 0xff, 16)) |
| return -1; |
| } |
| } |
| #endif |
| } |
| |
| return 0; |
| } |
| |
| /* get_fold_mark: Read fold mark from Unit Control Information #2, we use FOLD_MARK_IN_PROGRESS |
| * to indicate that we are in the progression of a Virtual Unit Chain folding. If the UCI #2 |
| * is FOLD_MARK_IN_PROGRESS when mounting the NFTL, the (previous) folding process is interrupted |
| * for some reason. A clean up/check of the VUC is necessary in this case. |
| * |
| * WARNING: return 0 if read error |
| */ |
| static int get_fold_mark(struct NFTLrecord *nftl, unsigned int block) |
| { |
| struct mtd_info *mtd = nftl->mbd.mtd; |
| struct nftl_uci2 uci; |
| size_t retlen; |
| |
| if (nftl_read_oob(mtd, block * nftl->EraseSize + 2 * SECTORSIZE + 8, |
| 8, &retlen, (char *)&uci) < 0) |
| return 0; |
| |
| return le16_to_cpu((uci.FoldMark | uci.FoldMark1)); |
| } |
| |
| int NFTL_mount(struct NFTLrecord *s) |
| { |
| int i; |
| unsigned int first_logical_block, logical_block, rep_block, nb_erases, erase_mark; |
| unsigned int block, first_block, is_first_block; |
| int chain_length, do_format_chain; |
| struct nftl_uci0 h0; |
| struct nftl_uci1 h1; |
| struct mtd_info *mtd = s->mbd.mtd; |
| size_t retlen; |
| |
| /* search for NFTL MediaHeader and Spare NFTL Media Header */ |
| if (find_boot_record(s) < 0) { |
| printk("Could not find valid boot record\n"); |
| return -1; |
| } |
| |
| /* init the logical to physical table */ |
| for (i = 0; i < s->nb_blocks; i++) { |
| s->EUNtable[i] = BLOCK_NIL; |
| } |
| |
| /* first pass : explore each block chain */ |
| first_logical_block = 0; |
| for (first_block = 0; first_block < s->nb_blocks; first_block++) { |
| /* if the block was not already explored, we can look at it */ |
| if (s->ReplUnitTable[first_block] == BLOCK_NOTEXPLORED) { |
| block = first_block; |
| chain_length = 0; |
| do_format_chain = 0; |
| |
| for (;;) { |
| /* read the block header. If error, we format the chain */ |
| if (nftl_read_oob(mtd, |
| block * s->EraseSize + 8, 8, |
| &retlen, (char *)&h0) < 0 || |
| nftl_read_oob(mtd, |
| block * s->EraseSize + |
| SECTORSIZE + 8, 8, |
| &retlen, (char *)&h1) < 0) { |
| s->ReplUnitTable[block] = BLOCK_NIL; |
| do_format_chain = 1; |
| break; |
| } |
| |
| logical_block = le16_to_cpu ((h0.VirtUnitNum | h0.SpareVirtUnitNum)); |
| rep_block = le16_to_cpu ((h0.ReplUnitNum | h0.SpareReplUnitNum)); |
| nb_erases = le32_to_cpu (h1.WearInfo); |
| erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1)); |
| |
| is_first_block = !(logical_block >> 15); |
| logical_block = logical_block & 0x7fff; |
| |
| /* invalid/free block test */ |
| if (erase_mark != ERASE_MARK || logical_block >= s->nb_blocks) { |
| if (chain_length == 0) { |
| /* if not currently in a chain, we can handle it safely */ |
| if (check_and_mark_free_block(s, block) < 0) { |
| /* not really free: format it */ |
| printk("Formatting block %d\n", block); |
| if (NFTL_formatblock(s, block) < 0) { |
| /* could not format: reserve the block */ |
| s->ReplUnitTable[block] = BLOCK_RESERVED; |
| } else { |
| s->ReplUnitTable[block] = BLOCK_FREE; |
| } |
| } else { |
| /* free block: mark it */ |
| s->ReplUnitTable[block] = BLOCK_FREE; |
| } |
| /* directly examine the next block. */ |
| goto examine_ReplUnitTable; |
| } else { |
| /* the block was in a chain : this is bad. We |
| must format all the chain */ |
| printk("Block %d: free but referenced in chain %d\n", |
| block, first_block); |
| s->ReplUnitTable[block] = BLOCK_NIL; |
| do_format_chain = 1; |
| break; |
| } |
| } |
| |
| /* we accept only first blocks here */ |
| if (chain_length == 0) { |
| /* this block is not the first block in chain : |
| ignore it, it will be included in a chain |
| later, or marked as not explored */ |
| if (!is_first_block) |
| goto examine_ReplUnitTable; |
| first_logical_block = logical_block; |
| } else { |
| if (logical_block != first_logical_block) { |
| printk("Block %d: incorrect logical block: %d expected: %d\n", |
| block, logical_block, first_logical_block); |
| /* the chain is incorrect : we must format it, |
| but we need to read it completely */ |
| do_format_chain = 1; |
| } |
| if (is_first_block) { |
| /* we accept that a block is marked as first |
| block while being last block in a chain |
| only if the chain is being folded */ |
| if (get_fold_mark(s, block) != FOLD_MARK_IN_PROGRESS || |
| rep_block != 0xffff) { |
| printk("Block %d: incorrectly marked as first block in chain\n", |
| block); |
| /* the chain is incorrect : we must format it, |
| but we need to read it completely */ |
| do_format_chain = 1; |
| } else { |
| printk("Block %d: folding in progress - ignoring first block flag\n", |
| block); |
| } |
| } |
| } |
| chain_length++; |
| if (rep_block == 0xffff) { |
| /* no more blocks after */ |
| s->ReplUnitTable[block] = BLOCK_NIL; |
| break; |
| } else if (rep_block >= s->nb_blocks) { |
| printk("Block %d: referencing invalid block %d\n", |
| block, rep_block); |
| do_format_chain = 1; |
| s->ReplUnitTable[block] = BLOCK_NIL; |
| break; |
| } else if (s->ReplUnitTable[rep_block] != BLOCK_NOTEXPLORED) { |
| /* same problem as previous 'is_first_block' test: |
| we accept that the last block of a chain has |
| the first_block flag set if folding is in |
| progress. We handle here the case where the |
| last block appeared first */ |
| if (s->ReplUnitTable[rep_block] == BLOCK_NIL && |
| s->EUNtable[first_logical_block] == rep_block && |
| get_fold_mark(s, first_block) == FOLD_MARK_IN_PROGRESS) { |
| /* EUNtable[] will be set after */ |
| printk("Block %d: folding in progress - ignoring first block flag\n", |
| rep_block); |
| s->ReplUnitTable[block] = rep_block; |
| s->EUNtable[first_logical_block] = BLOCK_NIL; |
| } else { |
| printk("Block %d: referencing block %d already in another chain\n", |
| block, rep_block); |
| /* XXX: should handle correctly fold in progress chains */ |
| do_format_chain = 1; |
| s->ReplUnitTable[block] = BLOCK_NIL; |
| } |
| break; |
| } else { |
| /* this is OK */ |
| s->ReplUnitTable[block] = rep_block; |
| block = rep_block; |
| } |
| } |
| |
| /* the chain was completely explored. Now we can decide |
| what to do with it */ |
| if (do_format_chain) { |
| /* invalid chain : format it */ |
| format_chain(s, first_block); |
| } else { |
| unsigned int first_block1, chain_to_format, chain_length1; |
| int fold_mark; |
| |
| /* valid chain : get foldmark */ |
| fold_mark = get_fold_mark(s, first_block); |
| if (fold_mark == 0) { |
| /* cannot get foldmark : format the chain */ |
| printk("Could read foldmark at block %d\n", first_block); |
| format_chain(s, first_block); |
| } else { |
| if (fold_mark == FOLD_MARK_IN_PROGRESS) |
| check_sectors_in_chain(s, first_block); |
| |
| /* now handle the case where we find two chains at the |
| same virtual address : we select the longer one, |
| because the shorter one is the one which was being |
| folded if the folding was not done in place */ |
| first_block1 = s->EUNtable[first_logical_block]; |
| if (first_block1 != BLOCK_NIL) { |
| /* XXX: what to do if same length ? */ |
| chain_length1 = calc_chain_length(s, first_block1); |
| printk("Two chains at blocks %d (len=%d) and %d (len=%d)\n", |
| first_block1, chain_length1, first_block, chain_length); |
| |
| if (chain_length >= chain_length1) { |
| chain_to_format = first_block1; |
| s->EUNtable[first_logical_block] = first_block; |
| } else { |
| chain_to_format = first_block; |
| } |
| format_chain(s, chain_to_format); |
| } else { |
| s->EUNtable[first_logical_block] = first_block; |
| } |
| } |
| } |
| } |
| examine_ReplUnitTable:; |
| } |
| |
| /* second pass to format unreferenced blocks and init free block count */ |
| s->numfreeEUNs = 0; |
| s->LastFreeEUN = le16_to_cpu(s->MediaHdr.FirstPhysicalEUN); |
| |
| for (block = 0; block < s->nb_blocks; block++) { |
| if (s->ReplUnitTable[block] == BLOCK_NOTEXPLORED) { |
| printk("Unreferenced block %d, formatting it\n", block); |
| if (NFTL_formatblock(s, block) < 0) |
| s->ReplUnitTable[block] = BLOCK_RESERVED; |
| else |
| s->ReplUnitTable[block] = BLOCK_FREE; |
| } |
| if (s->ReplUnitTable[block] == BLOCK_FREE) { |
| s->numfreeEUNs++; |
| s->LastFreeEUN = block; |
| } |
| } |
| |
| return 0; |
| } |