Re: [PATCH] btrfs: suppress a build warning on building 32bit kernel

[Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>]

Hi David,

On 2014/12/30 0:09, David Sterba wrote:
> On Thu, Dec 25, 2014 at 06:21:41PM +0900, Satoru Takeuchi wrote:
>> From: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
>> --- a/fs/btrfs/extent_io.c
>> +++ b/fs/btrfs/extent_io.c
>> @@ -2190,7 +2190,7 @@ void btrfs_free_io_failure_record(struct inode *inode, u64 start, u64 end)
>>
>>    		next = next_state(state);
>>
>> -		failrec = (struct io_failure_record *)state->private;
>> +		failrec = (struct io_failure_record *)(unsigned long)state->private;
>
> We're always using the 'private' data to store a pointer to
> 'struct io_failure_record *', please change the defintion in
> 'struct extent_state' instead of the typecasting.

Current definition is as follow.

===============================================================================
struct extent_state {
...
         /* for use by the FS */
         u64 private;
};
===============================================================================

It it OK to changing "u64 private" to "struct io_failure_record *failrec"
and change "{set,get}_state_private()" to "{set,get}_state_failrec()?
Or is it better to keep the name "private" as is and just change its type
to "unsigned long" or "(void *)"?

Thanks,
Satoru

>
>>    		free_extent_state(state);
>>    		kfree(failrec);