Re: [PATCH RFC 1/4] kmod: add a routine to return if usermode is disabled

[Mauro Carvalho Chehab <mchehab@redhat.com>]

Em 26-06-2012 17:38, Greg KH escreveu:
> On Tue, Jun 26, 2012 at 04:34:19PM -0300, Mauro Carvalho Chehab wrote:
>> Several media devices are only capable of probing the device if
>> the firmware load is enabled, e. g. when the usermode var is not
>> disabled.
>>
>> Add a routine to allow those drivers to test if probe can continue
>> or need to be deferred.
>>
>> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
>> ---
>>   include/linux/firmware.h |    6 ++++++
>>   kernel/kmod.c            |    6 ++++++
>>   2 files changed, 12 insertions(+)
>>
>> diff --git a/include/linux/firmware.h b/include/linux/firmware.h
>> index 1e7c011..cacf27e 100644
>> --- a/include/linux/firmware.h
>> +++ b/include/linux/firmware.h
>> @@ -35,6 +35,12 @@ struct builtin_fw {
>>   	static const struct builtin_fw __fw_concat(__builtin_fw,__COUNTER__) \
>>   	__used __section(.builtin_fw) = { name, blob, size }
>>   
>> +/**
>> + * is_usermodehelp_disabled - returns true if firmware usermode is disabled
>> + *			      false otherwise.
>> + */
>> +bool is_usermodehelp_disabled(void);
>> +
>>   #if defined(CONFIG_FW_LOADER) || (defined(CONFIG_FW_LOADER_MODULE) && defined(MODULE))
>>   int request_firmware(const struct firmware **fw, const char *name,
>>   		     struct device *device);
>> diff --git a/kernel/kmod.c b/kernel/kmod.c
>> index 05698a7..68901308 100644
>> --- a/kernel/kmod.c
>> +++ b/kernel/kmod.c
>> @@ -339,6 +339,12 @@ static DECLARE_WAIT_QUEUE_HEAD(running_helpers_waitq);
>>    */
>>   static DECLARE_WAIT_QUEUE_HEAD(usermodehelper_disabled_waitq);
>>   
>> +bool is_usermodehelp_disabled(void)
>> +{
>> +	return usermodehelper_disabled ? true : false;
>> +}
>> +EXPORT_SYMBOL_GPL(is_usermodehelp_disabled);
> 
> usermodehelper_disabled is an enum, and the 0 value is UMH_ENABLED, so I
> think you need to explicitly test for the correct value here, you don't
> want to return something incorrectly for UMH_FREEZING, right?

Yes. I'll change it to explicitly test for UMH_ENABLED.

Thanks!
Mauro