[PATCH] mm/zswap: constify struct kernel_param_ops uses

[PATCH] mm/zswap: constify struct kernel_param_ops uses

[Arvind Yadav]

kernel_param_ops are not supposed to change at runtime. All functions
working with kernel_param_ops provided by <linux/moduleparam.h> work
with const kernel_param_ops. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
---
 mm/zswap.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index d39581a..030fbf9 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -82,7 +82,7 @@ static u64 zswap_duplicate_entry;
 static bool zswap_enabled;
 static int zswap_enabled_param_set(const char *,
 				   const struct kernel_param *);
-static struct kernel_param_ops zswap_enabled_param_ops = {
+static const struct kernel_param_ops zswap_enabled_param_ops = {
 	.set =		zswap_enabled_param_set,
 	.get =		param_get_bool,
 };
@@ -93,7 +93,7 @@ module_param_cb(enabled, &zswap_enabled_param_ops, &zswap_enabled, 0644);
 static char *zswap_compressor = ZSWAP_COMPRESSOR_DEFAULT;
 static int zswap_compressor_param_set(const char *,
 				      const struct kernel_param *);
-static struct kernel_param_ops zswap_compressor_param_ops = {
+static const struct kernel_param_ops zswap_compressor_param_ops = {
 	.set =		zswap_compressor_param_set,
 	.get =		param_get_charp,
 	.free =		param_free_charp,
@@ -105,7 +105,7 @@ module_param_cb(compressor, &zswap_compressor_param_ops,
 #define ZSWAP_ZPOOL_DEFAULT "zbud"
 static char *zswap_zpool_type = ZSWAP_ZPOOL_DEFAULT;
 static int zswap_zpool_param_set(const char *, const struct kernel_param *);
-static struct kernel_param_ops zswap_zpool_param_ops = {
+static const struct kernel_param_ops zswap_zpool_param_ops = {
 	.set =		zswap_zpool_param_set,
 	.get =		param_get_charp,
 	.free =		param_free_charp,
-- 
2.7.4

Re: [PATCH] mm/zswap: constify struct kernel_param_ops uses

[Dan Streetman]

On Sat, Aug 26, 2017 at 1:41 PM, Arvind Yadav <arvind.yadav.cs@gmail.com> wrote:
> kernel_param_ops are not supposed to change at runtime. All functions
> working with kernel_param_ops provided by <linux/moduleparam.h> work
> with const kernel_param_ops. So mark the non-const structs as const.
>
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>

Reviewed-by: Dan Streetman <ddstreet@ieee.org>

> ---
>  mm/zswap.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/zswap.c b/mm/zswap.c
> index d39581a..030fbf9 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -82,7 +82,7 @@ static u64 zswap_duplicate_entry;
>  static bool zswap_enabled;
>  static int zswap_enabled_param_set(const char *,
>                                    const struct kernel_param *);
> -static struct kernel_param_ops zswap_enabled_param_ops = {
> +static const struct kernel_param_ops zswap_enabled_param_ops = {
>         .set =          zswap_enabled_param_set,
>         .get =          param_get_bool,
>  };
> @@ -93,7 +93,7 @@ module_param_cb(enabled, &zswap_enabled_param_ops, &zswap_enabled, 0644);
>  static char *zswap_compressor = ZSWAP_COMPRESSOR_DEFAULT;
>  static int zswap_compressor_param_set(const char *,
>                                       const struct kernel_param *);
> -static struct kernel_param_ops zswap_compressor_param_ops = {
> +static const struct kernel_param_ops zswap_compressor_param_ops = {
>         .set =          zswap_compressor_param_set,
>         .get =          param_get_charp,
>         .free =         param_free_charp,
> @@ -105,7 +105,7 @@ module_param_cb(compressor, &zswap_compressor_param_ops,
>  #define ZSWAP_ZPOOL_DEFAULT "zbud"
>  static char *zswap_zpool_type = ZSWAP_ZPOOL_DEFAULT;
>  static int zswap_zpool_param_set(const char *, const struct kernel_param *);
> -static struct kernel_param_ops zswap_zpool_param_ops = {
> +static const struct kernel_param_ops zswap_zpool_param_ops = {
>         .set =          zswap_zpool_param_set,
>         .get =          param_get_charp,
>         .free =         param_free_charp,
> --
> 2.7.4
>