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

[Aaron Conole <aconole@redhat.com>]

Eelco Chaudron <echaudro@redhat.com> writes:

> 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()

That looks like a bug.  If you have a patch already to go, please submit
it.  If not, I can cook one up.

Thanks for the catch, Eelco!

>> +	nspu_get_lockfile_path(lockname, sizeof(lockname), desc);
>>   	return 0;
>>   }