--- /dev/null
+/*
+ * 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;
+}
Code Review / kvmfornfv.git / blobdiff