From 11eaf6df1cce3c5e9f51b422aaedc42dc4aa1d37 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ezequiel=20Garc=C3=ADa?= Date: Fri, 1 Apr 2016 18:29:24 -0300 Subject: [PATCH] mtd: nand: Remove BUG() abuse in nand_scan_tail There's no reason to BUG() when parameters are being validated. Drivers can get things wrong, and it's much nicer to just throw a noisy warn and fail gracefully, than calling BUG() and throwing the whole system down the drain. Signed-off-by: Ezequiel Garcia Reviewed-by: Richard Weinberger Signed-off-by: Boris Brezillon --- drivers/mtd/nand/nand_base.c | 52 +++++++++++++++++++++++------------- 1 file changed, 33 insertions(+), 19 deletions(-) diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 728543b97dd8..0f0c5b190316 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -4107,10 +4107,12 @@ int nand_scan_tail(struct mtd_info *mtd) struct nand_chip *chip = mtd_to_nand(mtd); struct nand_ecc_ctrl *ecc = &chip->ecc; struct nand_buffers *nbuf; + int ret; /* New bad blocks should be marked in OOB, flash-based BBT, or both */ - BUG_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) && - !(chip->bbt_options & NAND_BBT_USE_FLASH)); + if (WARN_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) && + !(chip->bbt_options & NAND_BBT_USE_FLASH))) + return -EINVAL; if (!(chip->options & NAND_OWN_BUFFERS)) { nbuf = kzalloc(sizeof(*nbuf) + mtd->writesize @@ -4148,9 +4150,10 @@ int nand_scan_tail(struct mtd_info *mtd) ecc->layout = &nand_oob_128; break; default: - pr_warn("No oob scheme defined for oobsize %d\n", - mtd->oobsize); - BUG(); + WARN(1, "No oob scheme defined for oobsize %d\n", + mtd->oobsize); + ret = -EINVAL; + goto err_free; } } @@ -4166,8 +4169,9 @@ int nand_scan_tail(struct mtd_info *mtd) case NAND_ECC_HW_OOB_FIRST: /* Similar to NAND_ECC_HW, but a separate read_page handle */ if (!ecc->calculate || !ecc->correct || !ecc->hwctl) { - pr_warn("No ECC functions supplied; hardware ECC not possible\n"); - BUG(); + WARN(1, "No ECC functions supplied; hardware ECC not possible\n"); + ret = -EINVAL; + goto err_free; } if (!ecc->read_page) ecc->read_page = nand_read_page_hwecc_oob_first; @@ -4197,8 +4201,9 @@ int nand_scan_tail(struct mtd_info *mtd) ecc->read_page == nand_read_page_hwecc || !ecc->write_page || ecc->write_page == nand_write_page_hwecc)) { - pr_warn("No ECC functions supplied; hardware ECC not possible\n"); - BUG(); + WARN(1, "No ECC functions supplied; hardware ECC not possible\n"); + ret = -EINVAL; + goto err_free; } /* Use standard syndrome read/write page function? */ if (!ecc->read_page) @@ -4216,8 +4221,9 @@ int nand_scan_tail(struct mtd_info *mtd) if (mtd->writesize >= ecc->size) { if (!ecc->strength) { - pr_warn("Driver must set ecc.strength when using hardware ECC\n"); - BUG(); + WARN(1, "Driver must set ecc.strength when using hardware ECC\n"); + ret = -EINVAL; + goto err_free; } break; } @@ -4243,8 +4249,9 @@ int nand_scan_tail(struct mtd_info *mtd) case NAND_ECC_SOFT_BCH: if (!mtd_nand_has_bch()) { - pr_warn("CONFIG_MTD_NAND_ECC_BCH not enabled\n"); - BUG(); + WARN(1, "CONFIG_MTD_NAND_ECC_BCH not enabled\n"); + ret = -EINVAL; + goto err_free; } ecc->calculate = nand_bch_calculate_ecc; ecc->correct = nand_bch_correct_data; @@ -4269,8 +4276,9 @@ int nand_scan_tail(struct mtd_info *mtd) ecc->bytes = 0; ecc->priv = nand_bch_init(mtd); if (!ecc->priv) { - pr_warn("BCH ECC initialization failed!\n"); - BUG(); + WARN(1, "BCH ECC initialization failed!\n"); + ret = -EINVAL; + goto err_free; } break; @@ -4288,8 +4296,9 @@ int nand_scan_tail(struct mtd_info *mtd) break; default: - pr_warn("Invalid NAND_ECC_MODE %d\n", ecc->mode); - BUG(); + WARN(1, "Invalid NAND_ECC_MODE %d\n", ecc->mode); + ret = -EINVAL; + goto err_free; } /* For many systems, the standard OOB write also works for raw */ @@ -4319,8 +4328,9 @@ int nand_scan_tail(struct mtd_info *mtd) */ ecc->steps = mtd->writesize / ecc->size; if (ecc->steps * ecc->size != mtd->writesize) { - pr_warn("Invalid ECC parameters\n"); - BUG(); + WARN(1, "Invalid ECC parameters\n"); + ret = -EINVAL; + goto err_free; } ecc->total = ecc->steps * ecc->bytes; @@ -4398,6 +4408,10 @@ int nand_scan_tail(struct mtd_info *mtd) /* Build bad block table */ return chip->scan_bbt(mtd); +err_free: + if (!(chip->options & NAND_OWN_BUFFERS)) + kfree(chip->buffers); + return ret; } EXPORT_SYMBOL(nand_scan_tail);