From e6e620f0e15e3bc4b3bc3078c9f3285830f2fd3c Mon Sep 17 00:00:00 2001 From: Boris Brezillon Date: Mon, 22 Jan 2018 10:38:01 +0100 Subject: [PATCH] mtd: Make sure the device supports erase operations in mtd_erase() Some devices do not implement ->_erase() or have an invalid ->erasesize value. In this case, mtd_erase() should return -ENOTSUPP. Note that the test is not done on the MTD_NO_ERASE flag because this flag means 'erasing a block before writing to it is unnecessary', not 'the erase operation is not supported'. Actually, some drivers are setting the MTD_NO_ERASE flag but still implementing the ->_erase() hook and setting a valid ->erasesize value. Signed-off-by: Boris Brezillon Reviewed-by: Miquel Raynal Signed-off-by: Boris Brezillon --- drivers/mtd/mtdcore.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 28553c840d32..56cb037a1052 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -971,10 +971,14 @@ EXPORT_SYMBOL_GPL(__put_mtd_device); */ int mtd_erase(struct mtd_info *mtd, struct erase_info *instr) { + if (!mtd->erasesize || !mtd->_erase) + return -ENOTSUPP; + if (instr->addr >= mtd->size || instr->len > mtd->size - instr->addr) return -EINVAL; if (!(mtd->flags & MTD_WRITEABLE)) return -EROFS; + instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN; if (!instr->len) { instr->state = MTD_ERASE_DONE; -- 2.11.0