Re: [PATCH v2 1/2] dax: Introduce normal and recovery dax operation modes

[Jane Chu <jane.chu@oracle.com>]

On 11/5/2021 6:50 PM, Darrick J. Wong wrote:
> 
> <snip>
> 
>> diff --git a/include/linux/dax.h b/include/linux/dax.h
>> index 324363b798ec..931586df2905 100644
>> --- a/include/linux/dax.h
>> +++ b/include/linux/dax.h
>> @@ -9,6 +9,10 @@
>>   /* Flag for synchronous flush */
>>   #define DAXDEV_F_SYNC (1UL << 0)
>>   
>> +/* dax operation mode dynamically set by caller */
>> +#define	DAX_OP_NORMAL		0
>> +#define	DAX_OP_RECOVERY		1
> 
> Mostly looks ok to me, but since this is an operation mode, should this
> be an enum instead of an int?

Yeah, I tried enum at first, and then noticed that the
new dax enum type need to be introduced to device-mapper.h
by either include dax.h or define a mirrored enum, and
I wondered if that would be an over kill, so I ended up
settle on #define.

> 
> Granted I also think six arguments is a lot... though I don't really
> see any better way to do this.

Dan has a suggestion, and that'll reduce the number of args to 5.
> 
> (Dunno, I spent all day running internal patches through the process
> gauntlet so this is the remaining 2% of my brain speaking...)

Thanks!
-jane

> 
> --D
>