From c1194c793240330ce59500d67737e3f28b4bde40 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Fri, 3 Sep 2010 22:01:16 +0300 Subject: [PATCH] mtd: nand_base: do not cache pages with uncorrectable ECC errors Currently MTD caches the last read NAND page, even if there was an uncorrectable ECC error. This patch prevents caching in case of uncorrectable ECC errors. The reason is that we want to allow the user to re-read the NAND page several times. In case of unstable bits re-trying may help. Moreover, current behavior is wrong because the first read returns -EBADMSG (correctly) but the second read succeeds and incorrectly returns 0 (because we read from the cache). Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/nand/nand_base.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 922b890c8fcb..0b70c175999c 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -1505,7 +1505,8 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from, /* Transfer not aligned data */ if (!aligned) { - if (!NAND_SUBPAGE_READ(chip) && !oob) + if (!NAND_SUBPAGE_READ(chip) && !oob && + !(mtd->ecc_stats.failed - stats.failed)) chip->pagebuf = realpage; memcpy(buf, chip->buffers->databuf + col, bytes); } -- 2.30.2