From 335426c6dcdd338d6b7c939c2da15fc9c5dd4959 Mon Sep 17 00:00:00 2001 From: WeiXiong Liao Date: Wed, 25 Mar 2020 16:55:03 +0800 Subject: pstore/zone: Provide way to skip "broken" zone for MTD devices One requirement to support MTD devices in pstore/zone is having a way to declare certain regions as broken. Add this support to pstore/zone. The MTD driver should return -ENOMSG when encountering a bad region, which tells pstore/zone to skip and try the next one. Signed-off-by: WeiXiong Liao Link: https://lore.kernel.org/lkml/20200511233229.27745-8-keescook@chromium.org/ Co-developed-by: Colin Ian King Signed-off-by: Colin Ian King Link: //lore.kernel.org/lkml/20200512173801.222666-1-colin.king@canonical.com Signed-off-by: Kees Cook --- fs/pstore/blk.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'fs/pstore/blk.c') diff --git a/fs/pstore/blk.c b/fs/pstore/blk.c index e0d95fb48428..67343d6aa27a 100644 --- a/fs/pstore/blk.c +++ b/fs/pstore/blk.c @@ -109,9 +109,12 @@ struct bdev_info { * means error. * @write: The same as @read, but the following error number: * -EBUSY means try to write again later. + * -ENOMSG means to try next zone. * @panic_write:The write operation only used for panic case. It's optional - * if you do not care panic log. The parameters and return value - * are the same as @read. + * if you do not care panic log. The parameters are relative + * value to storage. + * On success, the number of bytes should be returned, others + * excluding -ENOMSG mean error. -ENOMSG means to try next zone. */ struct pstore_device_info { unsigned long total_size; @@ -337,6 +340,9 @@ static ssize_t psblk_blk_panic_write(const char *buf, size_t size, /* size and off must align to SECTOR_SIZE for block device */ ret = blkdev_panic_write(buf, off >> SECTOR_SHIFT, size >> SECTOR_SHIFT); + /* try next zone */ + if (ret == -ENOMSG) + return ret; return ret ? -EIO : size; } -- cgit v1.2.1