[PATCH v2] mtd: change len type from signed to unsigned type

[PATCH v2] mtd: change len type from signed to unsigned type

[Huijin Park]

From: "huijin.park" <huijin.park@samsung.com>

This patch casts the "len" parameter to an unsigned int.
The callers of erase_write() pass the "len" parameter as unsigned int.

Signed-off-by: huijin.park <huijin.park@samsung.com>
---
 drivers/mtd/mtdblock.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
index a5b1933..b2d5ed1 100644
--- a/drivers/mtd/mtdblock.c
+++ b/drivers/mtd/mtdblock.c
@@ -56,7 +56,7 @@ struct mtdblk_dev {
  */
 
 static int erase_write (struct mtd_info *mtd, unsigned long pos,
-			int len, const char *buf)
+			unsigned int len, const char *buf)
 {
 	struct erase_info erase;
 	size_t retlen;
-- 
1.7.9.5

Re: [PATCH v2] mtd: change len type from signed to unsigned type

[Miquel Raynal]

Hi Huijin,

Huijin Park <huijin.park@samsung.com> wrote on Thu, 15 Nov 2018
00:07:10 -0500:

> From: "huijin.park" <huijin.park@samsung.com>
> 
> This patch casts the "len" parameter to an unsigned int.
> The callers of erase_write() pass the "len" parameter as unsigned int.

Indeed. Perhaps it is worth backporting this patch to a stable releases?

> 
> Signed-off-by: huijin.park <huijin.park@samsung.com>
> ---
>  drivers/mtd/mtdblock.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
> index a5b1933..b2d5ed1 100644
> --- a/drivers/mtd/mtdblock.c
> +++ b/drivers/mtd/mtdblock.c
> @@ -56,7 +56,7 @@ struct mtdblk_dev {
>   */
>  
>  static int erase_write (struct mtd_info *mtd, unsigned long pos,
> -			int len, const char *buf)
> +			unsigned int len, const char *buf)
>  {
>  	struct erase_info erase;
>  	size_t retlen;

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>


Thanks,
Miquèl

Re: [PATCH v2] mtd: change len type from signed to unsigned type

[Huijin Park]

Hi Miquèl,

On Thu, Nov 15, 2018 at 6:29 PM Miquel Raynal <miquel.raynal@bootlin.com> wrote:
>
> Hi Huijin,
>
> Huijin Park <huijin.park@samsung.com> wrote on Thu, 15 Nov 2018
> 00:07:10 -0500:
>
> > From: "huijin.park" <huijin.park@samsung.com>
> >
> > This patch casts the "len" parameter to an unsigned int.
> > The callers of erase_write() pass the "len" parameter as unsigned int.
>
> Indeed. Perhaps it is worth backporting this patch to a stable releases?
>

It doesn't need backporting.
Because this patch is for enforcing code correctness.

> >
> > Signed-off-by: huijin.park <huijin.park@samsung.com>
> > ---
> >  drivers/mtd/mtdblock.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
> > index a5b1933..b2d5ed1 100644
> > --- a/drivers/mtd/mtdblock.c
> > +++ b/drivers/mtd/mtdblock.c
> > @@ -56,7 +56,7 @@ struct mtdblk_dev {
> >   */
> >
> >  static int erase_write (struct mtd_info *mtd, unsigned long pos,
> > -                     int len, const char *buf)
> > +                     unsigned int len, const char *buf)
> >  {
> >       struct erase_info erase;
> >       size_t retlen;
>
> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
>
>
> Thanks,
> Miquèl

Thanks,
Huijin

Re: [PATCH v2] mtd: change len type from signed to unsigned type

[Boris Brezillon]

On Thu, 15 Nov 2018 00:07:10 -0500
Huijin Park <huijin.park@samsung.com> wrote:

> From: "huijin.park" <huijin.park@samsung.com>
> 
> This patch casts the "len" parameter to an unsigned int.

Hm, that's not really what this patch actually. Actually it avoids the
cast from an int to an unsigned int.

> The callers of erase_write() pass the "len" parameter as unsigned int.

That's the important part here. Callers of erase_write() always pass an
unsigned int, so what you're trying to do here is avoid a cast to an
int.

> 
> Signed-off-by: huijin.park <huijin.park@samsung.com>
> ---

You should have a changelog here.

>  drivers/mtd/mtdblock.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c
> index a5b1933..b2d5ed1 100644
> --- a/drivers/mtd/mtdblock.c
> +++ b/drivers/mtd/mtdblock.c
> @@ -56,7 +56,7 @@ struct mtdblk_dev {
>   */
>  
>  static int erase_write (struct mtd_info *mtd, unsigned long pos,
> -			int len, const char *buf)
> +			unsigned int len, const char *buf)
>  {
>  	struct erase_info erase;
>  	size_t retlen;