[Devel] [PATCH rh7 v2] ve: fs -- Export fs.aio-max-nr via ve cgroup

[Kirill Tkhai]

On 09.04.2016 19:31, Cyrill Gorcunov wrote:
> This member represents fs.aio-max-nr sysctl entries. I think being able
> to c/r from libvzctl script is better in terms of keeping c/r work
> in one place, so instead of handling fs.aio-max-nr with sysctl utility
> from inside of ve context, I do it via scripts and for this sake
> fs.aio-max-nr is exported via cgroup api.
> 
> https://jira.sw.ru/browse/PSBM-45646
> 
> Signed-off-by: Cyrill Gorcunov <gorcunov at virtuozzo.com>
> CC: Vladimir Davydov <vdavydov at virtuozzo.com>
> CC: Konstantin Khorenko <khorenko at virtuozzo.com>

Acked-by: Kirill Tkhai <ktkhai at virtuozzo.com>

> ---
>  kernel/ve/ve.c |   17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> Index: linux-pcs7.git/kernel/ve/ve.c
> ===================================================================
> --- linux-pcs7.git.orig/kernel/ve/ve.c
> +++ linux-pcs7.git/kernel/ve/ve.c
> @@ -1180,7 +1180,8 @@ enum {
>  	VE_CF_IPTABLES_MASK,
>  	VE_CF_PSEUDOSUPER,
>  	VE_CF_CLOCK_MONOTONIC,
> -	VE_CF_CLOCK_BOOTBASED
> +	VE_CF_CLOCK_BOOTBASED,
> +	VE_CF_AIO_MAX_NR,
>  };
>  
>  static int ve_ts_read(struct cgroup *cg, struct cftype *cft, struct seq_file *m)
> @@ -1240,6 +1241,8 @@ static u64 ve_read_u64(struct cgroup *cg
>  #endif
>  	else if (cft->private == VE_CF_PSEUDOSUPER)
>  		return cgroup_ve(cg)->is_pseudosuper;
> +	else if (cft->private == VE_CF_AIO_MAX_NR)
> +		return cgroup_ve(cg)->aio_max_nr;
>  	return 0;
>  }
>  
> @@ -1276,7 +1279,8 @@ static int ve_write_u64(struct cgroup *c
>  {
>  	struct ve_struct *ve = cgroup_ve(cg);
>  
> -	if (!ve_is_super(get_exec_env()))
> +	if (!ve_is_super(get_exec_env()) &&
> +	    !ve->is_pseudosuper)
>  		return -EPERM;
>  
>  	down_write(&ve->op_sem);
> @@ -1291,6 +1295,8 @@ static int ve_write_u64(struct cgroup *c
>  	else if (cft->private == VE_CF_IPTABLES_MASK)
>  		ve->ipt_mask = ve_setup_iptables_mask(value);
>  #endif
> +	else if (cft->private == VE_CF_AIO_MAX_NR)
> +		ve->aio_max_nr = value;
>  	up_write(&ve->op_sem);
>  	return 0;
>  }
> @@ -1359,6 +1365,13 @@ static struct cftype ve_cftypes[] = {
>  		.write_string		= ve_ts_write,
>  		.private		= VE_CF_CLOCK_BOOTBASED,
>  	},
> +	{
> +		.name			= "aio_max_nr",
> +		.flags			= CFTYPE_NOT_ON_ROOT,
> +		.read_u64		= ve_read_u64,
> +		.write_u64		= ve_write_u64,
> +		.private		= VE_CF_AIO_MAX_NR,
> +	},
>  	{ }
>  };
>  
>