Subject: Re: [PATCH v3 net-next 1/5] device_cgroup: add DEVCG_ prefix to ACC_* and DEV_* constants

From: Joe Perches <[email-masked]>
Date: Thu, 02 Nov 2017 10:54:12 -0700

On Thu, 2017-11-02 at 13:15 -0400, Roman Gushchin wrote:
> Rename device type and access type constants defined in
> security/device_cgroup.c by adding the DEVCG_ prefix.
> 
> The reason behind this renaming is to make them global namespace
> friendly, as they will be moved to the corresponding header file
> by following patches.
[]
> diff --git a/security/device_cgroup.c b/security/device_cgroup.c
[]
> @@ -14,14 +14,14 @@
>  #include <linux/rcupdate.h>
>  #include <linux/mutex.h>
>  
> -#define ACC_MKNOD 1
> -#define ACC_READ  2
> -#define ACC_WRITE 4
> -#define ACC_MASK (ACC_MKNOD | ACC_READ | ACC_WRITE)
> +#define DEVCG_ACC_MKNOD 1
> +#define DEVCG_ACC_READ  2
> +#define DEVCG_ACC_WRITE 4
> +#define DEVCG_ACC_MASK (DEVCG_ACC_MKNOD | DEVCG_ACC_READ | DEVCG_ACC_WRITE)

trivia:

major and minor are u32 but all the
type and access uses seem to be "short"

Perhaps u16 (or __u16 if uapi public) instead?

> -#define DEV_BLOCK 1
> -#define DEV_CHAR  2
> -#define DEV_ALL   4  /* this represents all devices */
> +#define DEVCG_DEV_BLOCK 1
> +#define DEVCG_DEV_CHAR  2
> +#define DEVCG_DEV_ALL   4  /* this represents all devices */
>  
>  static DEFINE_MUTEX(devcgroup_mutex);
>  
> @@ -245,21 +245,21 @@ static void set_access(char *acc, short access)
>  {
>  	int idx = 0;
>  	memset(acc, 0, ACCLEN);
> -	if (access & ACC_READ)
> +	if (access & DEVCG_ACC_READ)
>  		acc[idx++] = 'r';
> -	if (access & ACC_WRITE)
> +	if (access & DEVCG_ACC_WRITE)
>  		acc[idx++] = 'w';
> -	if (access & ACC_MKNOD)
> +	if (access & DEVCG_ACC_MKNOD)
>  		acc[idx++] = 'm';
>  }
>  
>  static char type_to_char(short type)
>  {
> -	if (type == DEV_ALL)
> +	if (type == DEVCG_DEV_ALL)
>  		return 'a';
> -	if (type == DEV_CHAR)
> +	if (type == DEVCG_DEV_CHAR)
>  		return 'c';
> -	if (type == DEV_BLOCK)
> +	if (type == DEVCG_DEV_BLOCK)
>  		return 'b';
>  	return 'X';
>  }