[systemd-devel] [PATCH] metadata: reflect change in task_cgroup_name

[Daniel Mack]

On 04/09/2014 07:20 PM, Hristo Venev wrote:
> On Wed, 2014-04-09 at 15:04 +0200, Daniel Mack wrote:
>> Eh. Thanks for spotting this. However, I think we should have a compat
>> workaround for 3.14, for at least a couple of weeks. We can drop it
>> after that. Could you amend your patch for that?
> 
> How do I check if the kernel version is 3.14.0 or 3.14.0+?
> linux/version.h is the same. I've amended the patch to check for 3.15.0
> so it will be broken until the release of 3.15.0-rc1.
> 
>> Apart from that, please take care to follow the kernel CodingStyle. In
>> particular, we use tabs for indentation, not spaces.
> 
> Done.

Thanks, applied with a small style fixup: I moved the # characters to
the first column.


Thanks,
Daniel


> 
> ---
>  metadata.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/metadata.c b/metadata.c
> index 5b47bb2..1dab96e 100644
> --- a/metadata.c
> +++ b/metadata.c
> @@ -23,6 +23,7 @@
>  #include <linux/sizes.h>
>  #include <linux/slab.h>
>  #include <linux/uaccess.h>
> +#include <linux/version.h>
>  
>  #include "connection.h"
>  #include "message.h"
> @@ -335,18 +336,29 @@ static int kdbus_meta_append_caps(struct
> kdbus_meta *meta)
>  #ifdef CONFIG_CGROUPS
>  static int kdbus_meta_append_cgroup(struct kdbus_meta *meta)
>  {
> -	char *tmp;
> +	char *buf, *path;
>  	int ret;
>  
> -	tmp = (char *)__get_free_page(GFP_TEMPORARY | __GFP_ZERO);
> -	if (!tmp)
> +	buf = (char *)__get_free_page(GFP_TEMPORARY | __GFP_ZERO);
> +	if (!buf)
>  		return -ENOMEM;
>  
> -	ret = task_cgroup_path(current, tmp, PAGE_SIZE);
> -	if (ret >= 0)
> -		ret = kdbus_meta_append_str(meta, KDBUS_ITEM_CGROUP, tmp);
> +	#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,15,0)
> +	path = task_cgroup_path(current, buf, PAGE_SIZE);
> +	#else
> +	ret = task_cgroup_path(current, buf, PAGE_SIZE);
> +	if (ret < 0)
> +		path = NULL;
> +	else
> +		path = buf;
> +	#endif
>  
> -	free_page((unsigned long) tmp);
> +	if (path)
> +		ret = kdbus_meta_append_str(meta, KDBUS_ITEM_CGROUP, path);
> +	else
> +		ret = -ENAMETOOLONG;
> +
> +	free_page((unsigned long) buf);
>  
>  	return ret;
>  }
>