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Diffstat (limited to 'fs/yaffs2/yaffs_mtdif1.c')
| -rw-r--r-- | fs/yaffs2/yaffs_mtdif1.c | 369 |
1 files changed, 0 insertions, 369 deletions
diff --git a/fs/yaffs2/yaffs_mtdif1.c b/fs/yaffs2/yaffs_mtdif1.c deleted file mode 100644 index 36185b6..0000000 --- a/fs/yaffs2/yaffs_mtdif1.c +++ /dev/null @@ -1,369 +0,0 @@ -/* - * YAFFS: Yet another FFS. A NAND-flash specific file system. - * yaffs_mtdif1.c NAND mtd interface functions for small-page NAND. - * - * Copyright (C) 2002 Aleph One Ltd. - * for Toby Churchill Ltd and Brightstar Engineering - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ - -/* - * This module provides the interface between yaffs_nand.c and the - * MTD API. This version is used when the MTD interface supports the - * 'mtd_oob_ops' style calls to read_oob and write_oob, circa 2.6.17, - * and we have small-page NAND device. - * - * These functions are invoked via function pointers in yaffs_nand.c. - * This replaces functionality provided by functions in yaffs_mtdif.c - * and the yaffs_TagsCompatability functions in yaffs_tagscompat.c that are - * called in yaffs_mtdif.c when the function pointers are NULL. - * We assume the MTD layer is performing ECC (useNANDECC is true). - */ - -#include "yportenv.h" -#include "yaffs_guts.h" -#include "yaffs_packedtags1.h" -#include "yaffs_tagscompat.h" // for yaffs_CalcTagsECC - -#include "linux/kernel.h" -#include "linux/version.h" -#include "linux/types.h" -#include "linux/mtd/mtd.h" - -/* Don't compile this module if we don't have MTD's mtd_oob_ops interface */ -#if (LINUX_VERSION_CODE > KERNEL_VERSION(2,6,17)) - -const char *yaffs_mtdif1_c_version = "$Id: yaffs_mtdif1.c,v 1.5 2007/10/29 14:59:57 imcd Exp $"; - -#ifndef CONFIG_YAFFS_9BYTE_TAGS -# define YTAG1_SIZE 8 -#else -# define YTAG1_SIZE 9 -#endif - -#if 0 -/* Use the following nand_ecclayout with MTD when using - * CONFIG_YAFFS_9BYTE_TAGS and the older on-NAND tags layout. - * If you have existing Yaffs images and the byte order differs from this, - * adjust 'oobfree' to match your existing Yaffs data. - * - * This nand_ecclayout scatters/gathers to/from the old-yaffs layout with the - * pageStatus byte (at NAND spare offset 4) scattered/gathered from/to - * the 9th byte. - * - * Old-style on-NAND format: T0,T1,T2,T3,P,B,T4,T5,E0,E1,E2,T6,T7,E3,E4,E5 - * We have/need PackedTags1 plus pageStatus: T0,T1,T2,T3,T4,T5,T6,T7,P - * where Tn are the tag bytes, En are MTD's ECC bytes, P is the pageStatus - * byte and B is the small-page bad-block indicator byte. - */ -static struct nand_ecclayout nand_oob_16 = { - .eccbytes = 6, - .eccpos = { 8, 9, 10, 13, 14, 15 }, - .oobavail = 9, - .oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } } -}; -#endif - -/* Write a chunk (page) of data to NAND. - * - * Caller always provides ExtendedTags data which are converted to a more - * compact (packed) form for storage in NAND. A mini-ECC runs over the - * contents of the tags meta-data; used to valid the tags when read. - * - * - Pack ExtendedTags to PackedTags1 form - * - Compute mini-ECC for PackedTags1 - * - Write data and packed tags to NAND. - * - * Note: Due to the use of the PackedTags1 meta-data which does not include - * a full sequence number (as found in the larger PackedTags2 form) it is - * necessary for Yaffs to re-write a chunk/page (just once) to mark it as - * discarded and dirty. This is not ideal: newer NAND parts are supposed - * to be written just once. When Yaffs performs this operation, this - * function is called with a NULL data pointer -- calling MTD write_oob - * without data is valid usage (2.6.17). - * - * Any underlying MTD error results in YAFFS_FAIL. - * Returns YAFFS_OK or YAFFS_FAIL. - */ -int nandmtd1_WriteChunkWithTagsToNAND(yaffs_Device *dev, - int chunkInNAND, const __u8 * data, const yaffs_ExtendedTags * etags) -{ - struct mtd_info * mtd = dev->genericDevice; - int chunkBytes = dev->nDataBytesPerChunk; - loff_t addr = ((loff_t)chunkInNAND) * chunkBytes; - struct mtd_oob_ops ops; - yaffs_PackedTags1 pt1; - int retval; - - /* we assume that PackedTags1 and yaffs_Tags are compatible */ - compile_time_assertion(sizeof(yaffs_PackedTags1) == 12); - compile_time_assertion(sizeof(yaffs_Tags) == 8); - - dev->nPageWrites++; - - yaffs_PackTags1(&pt1, etags); - yaffs_CalcTagsECC((yaffs_Tags *)&pt1); - - /* When deleting a chunk, the upper layer provides only skeletal - * etags, one with chunkDeleted set. However, we need to update the - * tags, not erase them completely. So we use the NAND write property - * that only zeroed-bits stick and set tag bytes to all-ones and - * zero just the (not) deleted bit. - */ -#ifndef CONFIG_YAFFS_9BYTE_TAGS - if (etags->chunkDeleted) { - memset(&pt1, 0xff, 8); - /* clear delete status bit to indicate deleted */ - pt1.deleted = 0; - } -#else - ((__u8 *)&pt1)[8] = 0xff; - if (etags->chunkDeleted) { - memset(&pt1, 0xff, 8); - /* zero pageStatus byte to indicate deleted */ - ((__u8 *)&pt1)[8] = 0; - } -#endif - - memset(&ops, 0, sizeof(ops)); - ops.mode = MTD_OOB_AUTO; - ops.len = (data) ? chunkBytes : 0; - ops.ooblen = YTAG1_SIZE; - ops.datbuf = (__u8 *)data; - ops.oobbuf = (__u8 *)&pt1; - - retval = mtd->write_oob(mtd, addr, &ops); - if (retval) { - yaffs_trace(YAFFS_TRACE_MTD, - "write_oob failed, chunk %d, mtd error %d\n", - chunkInNAND, retval); - } - return retval ? YAFFS_FAIL : YAFFS_OK; -} - -/* Return with empty ExtendedTags but add eccResult. - */ -static int rettags(yaffs_ExtendedTags * etags, int eccResult, int retval) -{ - if (etags) { - memset(etags, 0, sizeof(*etags)); - etags->eccResult = eccResult; - } - return retval; -} - -/* Read a chunk (page) from NAND. - * - * Caller expects ExtendedTags data to be usable even on error; that is, - * all members except eccResult and blockBad are zeroed. - * - * - Check ECC results for data (if applicable) - * - Check for blank/erased block (return empty ExtendedTags if blank) - * - Check the PackedTags1 mini-ECC (correct if necessary/possible) - * - Convert PackedTags1 to ExtendedTags - * - Update eccResult and blockBad members to refect state. - * - * Returns YAFFS_OK or YAFFS_FAIL. - */ -int nandmtd1_ReadChunkWithTagsFromNAND(yaffs_Device *dev, - int chunkInNAND, __u8 * data, yaffs_ExtendedTags * etags) -{ - struct mtd_info * mtd = dev->genericDevice; - int chunkBytes = dev->nDataBytesPerChunk; - loff_t addr = ((loff_t)chunkInNAND) * chunkBytes; - int eccres = YAFFS_ECC_RESULT_NO_ERROR; - struct mtd_oob_ops ops; - yaffs_PackedTags1 pt1; - int retval; - int deleted; - - dev->nPageReads++; - - memset(&ops, 0, sizeof(ops)); - ops.mode = MTD_OOB_AUTO; - ops.len = (data) ? chunkBytes : 0; - ops.ooblen = YTAG1_SIZE; - ops.datbuf = data; - ops.oobbuf = (__u8 *)&pt1; - -#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,20)) - /* In MTD 2.6.18 to 2.6.19 nand_base.c:nand_do_read_oob() has a bug; - * help it out with ops.len = ops.ooblen when ops.datbuf == NULL. - */ - ops.len = (ops.datbuf) ? ops.len : ops.ooblen; -#endif - /* Read page and oob using MTD. - * Check status and determine ECC result. - */ - retval = mtd->read_oob(mtd, addr, &ops); - if (retval) { - yaffs_trace(YAFFS_TRACE_MTD, - "read_oob failed, chunk %d, mtd error %d\n", - chunkInNAND, retval); - } - - switch (retval) { - case 0: - /* no error */ - break; - - case -EUCLEAN: - /* MTD's ECC fixed the data */ - eccres = YAFFS_ECC_RESULT_FIXED; - dev->eccFixed++; - break; - - case -EBADMSG: - /* MTD's ECC could not fix the data */ - dev->eccUnfixed++; - /* fall into... */ - default: - rettags(etags, YAFFS_ECC_RESULT_UNFIXED, 0); - etags->blockBad = (mtd->block_isbad)(mtd, addr); - return YAFFS_FAIL; - } - - /* Check for a blank/erased chunk. - */ - if (yaffs_CheckFF((__u8 *)&pt1, 8)) { - /* when blank, upper layers want eccResult to be <= NO_ERROR */ - return rettags(etags, YAFFS_ECC_RESULT_NO_ERROR, YAFFS_OK); - } - -#ifndef CONFIG_YAFFS_9BYTE_TAGS - /* Read deleted status (bit) then return it to it's non-deleted - * state before performing tags mini-ECC check. pt1.deleted is - * inverted. - */ - deleted = !pt1.deleted; - pt1.deleted = 1; -#else - deleted = (yaffs_CountBits(((__u8 *)&pt1)[8]) < 7); -#endif - - /* Check the packed tags mini-ECC and correct if necessary/possible. - */ - retval = yaffs_CheckECCOnTags((yaffs_Tags *)&pt1); - switch (retval) { - case 0: - /* no tags error, use MTD result */ - break; - case 1: - /* recovered tags-ECC error */ - dev->tagsEccFixed++; - if (eccres == YAFFS_ECC_RESULT_NO_ERROR) - eccres = YAFFS_ECC_RESULT_FIXED; - break; - default: - /* unrecovered tags-ECC error */ - dev->tagsEccUnfixed++; - return rettags(etags, YAFFS_ECC_RESULT_UNFIXED, YAFFS_FAIL); - } - - /* Unpack the tags to extended form and set ECC result. - * [set shouldBeFF just to keep yaffs_UnpackTags1 happy] - */ - pt1.shouldBeFF = 0xFFFFFFFF; - yaffs_UnpackTags1(etags, &pt1); - etags->eccResult = eccres; - - /* Set deleted state */ - etags->chunkDeleted = deleted; - return YAFFS_OK; -} - -/* Mark a block bad. - * - * This is a persistant state. - * Use of this function should be rare. - * - * Returns YAFFS_OK or YAFFS_FAIL. - */ -int nandmtd1_MarkNANDBlockBad(struct yaffs_DeviceStruct *dev, int blockNo) -{ - struct mtd_info * mtd = dev->genericDevice; - int blocksize = dev->nChunksPerBlock * dev->nDataBytesPerChunk; - int retval; - - yaffs_trace(YAFFS_TRACE_BAD_BLOCKS, "marking block %d bad\n", blockNo); - - retval = mtd->block_markbad(mtd, (loff_t)blocksize * blockNo); - return (retval) ? YAFFS_FAIL : YAFFS_OK; -} - -/* Check any MTD prerequists. - * - * Returns YAFFS_OK or YAFFS_FAIL. - */ -static int nandmtd1_TestPrerequists(struct mtd_info * mtd) -{ - /* 2.6.18 has mtd->ecclayout->oobavail */ - /* 2.6.21 has mtd->ecclayout->oobavail and mtd->oobavail */ - int oobavail = mtd->ecclayout->oobavail; - - if (oobavail < YTAG1_SIZE) { - yaffs_trace(YAFFS_TRACE_ERROR, - "mtd device has only %d bytes for tags, need %d\n", - oobavail, YTAG1_SIZE); - return YAFFS_FAIL; - } - return YAFFS_OK; -} - -/* Query for the current state of a specific block. - * - * Examine the tags of the first chunk of the block and return the state: - * - YAFFS_BLOCK_STATE_DEAD, the block is marked bad - * - YAFFS_BLOCK_STATE_NEEDS_SCANNING, the block is in use - * - YAFFS_BLOCK_STATE_EMPTY, the block is clean - * - * Always returns YAFFS_OK. - */ -int nandmtd1_QueryNANDBlock(struct yaffs_DeviceStruct *dev, int blockNo, - yaffs_BlockState * pState, int *pSequenceNumber) -{ - struct mtd_info * mtd = dev->genericDevice; - int chunkNo = blockNo * dev->nChunksPerBlock; - loff_t addr = (loff_t)chunkNo * dev->nDataBytesPerChunk; - yaffs_ExtendedTags etags; - int state = YAFFS_BLOCK_STATE_DEAD; - int seqnum = 0; - int retval; - - /* We don't yet have a good place to test for MTD config prerequists. - * Do it here as we are called during the initial scan. - */ - if (nandmtd1_TestPrerequists(mtd) != YAFFS_OK) { - return YAFFS_FAIL; - } - - retval = nandmtd1_ReadChunkWithTagsFromNAND(dev, chunkNo, NULL, &etags); - etags.blockBad = (mtd->block_isbad)(mtd, addr); - if (etags.blockBad) { - yaffs_trace(YAFFS_TRACE_BAD_BLOCKS, - "block %d is marked bad\n", blockNo); - state = YAFFS_BLOCK_STATE_DEAD; - } - else if (etags.eccResult != YAFFS_ECC_RESULT_NO_ERROR) { - /* bad tags, need to look more closely */ - state = YAFFS_BLOCK_STATE_NEEDS_SCANNING; - } - else if (etags.chunkUsed) { - state = YAFFS_BLOCK_STATE_NEEDS_SCANNING; - seqnum = etags.sequenceNumber; - } - else { - state = YAFFS_BLOCK_STATE_EMPTY; - } - - *pState = state; - *pSequenceNumber = seqnum; - - /* query always succeeds */ - return YAFFS_OK; -} - -#endif /*KERNEL_VERSION*/ |