Re: [dpdk-stable] [PATCH 2/2] nfp: allow for non-root user

[Eelco Chaudron <echaudro@redhat.com>]

On 30/04/18 19:20, Aaron Conole wrote:
> Currently, the nfp lock files are taken from the global lock file
> location, which will work when the user is running as root.  However,
> some distributions and applications (notably ovs 2.8+ on RHEL/Fedora)
> run as a non-root user.
>
> Acked-by: Alejandro Lucero <alejandro.lucero@netronome.com>
> Signed-off-by: Aaron Conole <aconole@redhat.com>
> ---
>   drivers/net/nfp/nfp_nfpu.c | 23 ++++++++++++++++++-----
>   1 file changed, 18 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/nfp/nfp_nfpu.c b/drivers/net/nfp/nfp_nfpu.c
> index 2ed985ff4..ae2e07220 100644
> --- a/drivers/net/nfp/nfp_nfpu.c
> +++ b/drivers/net/nfp/nfp_nfpu.c
> @@ -18,6 +18,22 @@
>   #define NFP_CFG_EXP_BAR         7
>   
>   #define NFP_CFG_EXP_BAR_CFG_BASE	0x30000
> +#define NFP_LOCKFILE_PATH_FMT "%s/nfp%d"
> +
> +/* get nfp lock file path (/var/lock if root, $HOME otherwise) */
> +static void
> +nspu_get_lockfile_path(char *buffer, int bufsz, nfpu_desc_t *desc)
> +{
> +	const char *dir = "/var/lock";
> +	const char *home_dir = getenv("HOME");
> +
> +	if (getuid() != 0 && home_dir != NULL)
> +		dir = home_dir;
> +
> +	/* use current prefix as file path */
> +	snprintf(buffer, bufsz, NFP_LOCKFILE_PATH_FMT, dir,
> +			desc->nfp);
> +}
>   
>   /* There could be other NFP userspace tools using the NSP interface.
>    * Make sure there is no other process using it and locking the access for
> @@ -30,9 +46,7 @@ nspv_aquire_process_lock(nfpu_desc_t *desc)
>   	struct flock lock;
>   	char lockname[30];
>   
> -	memset(&lock, 0, sizeof(lock));
> -
> -	snprintf(lockname, sizeof(lockname), "/var/lock/nfp%d", desc->nfp);
> +	nspu_get_lockfile_path(lockname, sizeof(lockname), desc);
>   
>   	/* Using S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH */
>   	desc->lock = open(lockname, O_RDWR | O_CREAT, 0666);
> @@ -106,7 +120,6 @@ nfpu_close(nfpu_desc_t *desc)
>   	rte_free(desc->nspu);
>   	close(desc->lock);
>   
> -	snprintf(lockname, sizeof(lockname), "/var/lock/nfp%d", desc->nfp);
> -	unlink(lockname);
Sorry for being late, but was this unlink() removed by accident? And 
should be below nspu_get_lockfile_path()
> +	nspu_get_lockfile_path(lockname, sizeof(lockname), desc);
>   	return 0;
>   }