openwrt/target/linux/generic/backport-4.19/048-v4.21-mtd-improve-calcu...

56 lines
1.8 KiB
Diff

From 6750f61a13a0197c40e4a40739117493b15f19e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Tue, 20 Nov 2018 10:24:09 +0100
Subject: [PATCH] mtd: improve calculating partition boundaries when checking
for alignment
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When checking for alignment mtd should check absolute offsets. It's
important for subpartitions as it doesn't make sense to check their
relative addresses.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
---
drivers/mtd/mtdpart.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -61,6 +61,15 @@ static inline struct mtd_part *mtd_to_pa
return container_of(mtd, struct mtd_part, mtd);
}
+static u64 part_absolute_offset(struct mtd_info *mtd)
+{
+ struct mtd_part *part = mtd_to_part(mtd);
+
+ if (!mtd_is_partition(mtd))
+ return 0;
+
+ return part_absolute_offset(part->parent) + part->offset;
+}
/*
* MTD methods which simply translate the effective address and pass through
@@ -518,7 +527,7 @@ static struct mtd_part *allocate_partiti
if (!(slave->mtd.flags & MTD_NO_ERASE))
wr_alignment = slave->mtd.erasesize;
- tmp = slave->offset;
+ tmp = part_absolute_offset(parent) + slave->offset;
remainder = do_div(tmp, wr_alignment);
if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
/* Doesn't start on a boundary of major erase size */
@@ -529,7 +538,7 @@ static struct mtd_part *allocate_partiti
part->name);
}
- tmp = slave->mtd.size;
+ tmp = part_absolute_offset(parent) + slave->mtd.size;
remainder = do_div(tmp, wr_alignment);
if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) {
slave->mtd.flags &= ~MTD_WRITEABLE;