diff mbox series

[V2] mtd: improve calculating partition boundaries when checking for alignment

Message ID 20181120092409.13864-1-zajec5@gmail.com
State Accepted
Delegated to: Boris Brezillon
Headers show
Series [V2] mtd: improve calculating partition boundaries when checking for alignment | expand

Commit Message

Rafał Miłecki Nov. 20, 2018, 9:24 a.m. UTC
From: Rafał Miłecki <rafal@milecki.pl>

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>
---
V2: Switch from uint64_t to u64. I got incorrectly inspired by
    uint64_t offset;
---
 drivers/mtd/mtdpart.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Comments

Boris Brezillon Dec. 3, 2018, 7:53 a.m. UTC | #1
On Tue, 20 Nov 2018 10:24:09 +0100
Rafał Miłecki <zajec5@gmail.com> wrote:

> From: Rafał Miłecki <rafal@milecki.pl>
> 
> 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>

Queued to mtd/next.

> ---
> V2: Switch from uint64_t to u64. I got incorrectly inspired by
>     uint64_t offset;
> ---
>  drivers/mtd/mtdpart.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
> index 2b6e53af47da..b6af41b04622 100644
> --- a/drivers/mtd/mtdpart.c
> +++ b/drivers/mtd/mtdpart.c
> @@ -61,6 +61,15 @@ static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
>  	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
> @@ -514,7 +523,7 @@ static struct mtd_part *allocate_partition(struct mtd_info *parent,
>  	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 */
> @@ -525,7 +534,7 @@ static struct mtd_part *allocate_partition(struct mtd_info *parent,
>  			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;
diff mbox series

Patch

diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index 2b6e53af47da..b6af41b04622 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -61,6 +61,15 @@  static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
 	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
@@ -514,7 +523,7 @@  static struct mtd_part *allocate_partition(struct mtd_info *parent,
 	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 */
@@ -525,7 +534,7 @@  static struct mtd_part *allocate_partition(struct mtd_info *parent,
 			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;