Re: [PATCH for-next 03/10] RDMA/rtrs: Use sysfs_emit instead of s*printf function for sysfs show

[Leon Romanovsky <leon@kernel.org>]

On Fri, Jul 30, 2021 at 03:18:25PM +0200, Jack Wang wrote:
> From: Md Haris Iqbal <haris.iqbal@ionos.com>
> 
> sysfs_emit function was added to be aware of the PAGE_SIZE maximum of
> the temporary buffer used for outputting sysfs content, so there is no
> possible overruns. So replace the uses of any s*printf functions for
> the sysfs show functions with sysfs_emit.
> 
> Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
> Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
> ---
>  drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c | 24 +++++++++-----------
>  drivers/infiniband/ulp/rtrs/rtrs-srv-sysfs.c |  2 +-
>  2 files changed, 12 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> index 26bbe5d6dff5..c5c047aa45a4 100644
> --- a/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> +++ b/drivers/infiniband/ulp/rtrs/rtrs-clt-stats.c
> @@ -45,24 +45,23 @@ int rtrs_clt_stats_migration_cnt_to_str(struct rtrs_clt_stats *stats,
>  	size_t used;
>  	int cpu;
>  
> -	used = scnprintf(buf, len, "    ");
> +	used = sysfs_emit(buf, "    ");
>  	for_each_possible_cpu(cpu)
> -		used += scnprintf(buf + used, len - used, " CPU%u", cpu);
> +		used += sysfs_emit_at(buf, used, " CPU%u", cpu);
>  
> -	used += scnprintf(buf + used, len - used, "\nfrom:");
> +	used += sysfs_emit_at(buf, used, "\nfrom:");

"\nfrom" and "\nto" are abuse of sysfs rules.
https://lore.kernel.org/kernelnewbies/7a353c64-a81f-a149-9541-ef328a197761@gmail.com/T/#m8bf898fcdb4a5371781bbc9646993a50fa950fbc
https://lore.kernel.org/kernelnewbies/7a353c64-a81f-a149-9541-ef328a197761@gmail.com/T/#m9ce6f045a863597922012d71a6719d6d90c8e0a6

Thanks