From 3fbe507ebd828bc8ce747181a204ddafbe5cce2f Mon Sep 17 00:00:00 2001 From: Matt Weber Date: Tue, 2 Jun 2020 09:34:03 -0500 Subject: [PATCH] mtd: mtdconcat: map through panic write handler Allows a mtdconcat's subdevice->_panic_write to be used for capturing a mtdoops dump. Note: The ->_panic_write is mapped through from the first chip that is part of the concat virtual device. Signed-off-by: Matthew Weber [miquel.raynal@bootlin.com: return err, not void] Signed-off-by: Miquel Raynal Link: https://lore.kernel.org/linux-mtd/20200602143403.13465-1-matthew.weber@rockwellcollins.com --- drivers/mtd/mtdconcat.c | 44 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c index 1d6c9e7e7b7d..242c3a660002 100644 --- a/drivers/mtd/mtdconcat.c +++ b/drivers/mtd/mtdconcat.c @@ -102,6 +102,48 @@ concat_read(struct mtd_info *mtd, loff_t from, size_t len, return -EINVAL; } +static int +concat_panic_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t * retlen, const u_char * buf) +{ + struct mtd_concat *concat = CONCAT(mtd); + int err = -EINVAL; + int i; + for (i = 0; i < concat->num_subdev; i++) { + struct mtd_info *subdev = concat->subdev[i]; + size_t size, retsize; + + if (to >= subdev->size) { + size = 0; + to -= subdev->size; + continue; + } + if (to + len > subdev->size) + size = subdev->size - to; + else + size = len; + + err = mtd_panic_write(subdev, to, size, &retsize, buf); + if (err == -EOPNOTSUPP) { + printk(KERN_ERR "mtdconcat: Cannot write from panic without panic_write\n"); + return err; + } + if (err) + break; + + *retlen += retsize; + len -= size; + if (len == 0) + break; + + err = -EINVAL; + buf += size; + to = 0; + } + return err; +} + + static int concat_write(struct mtd_info *mtd, loff_t to, size_t len, size_t * retlen, const u_char * buf) @@ -648,6 +690,8 @@ struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to c concat->mtd._block_isbad = concat_block_isbad; if (subdev[0]->_block_markbad) concat->mtd._block_markbad = concat_block_markbad; + if (subdev[0]->_panic_write) + concat->mtd._panic_write = concat_panic_write; concat->mtd.ecc_stats.badblocks = subdev[0]->ecc_stats.badblocks;