[Ocfs2-devel] [PATCH] Track negative dentries

[Goldwyn Rodrigues]

On Wed, Jun 23, 2010 at 4:01 PM, Joel Becker <Joel.Becker at oracle.com> wrote:
> On Wed, Jun 23, 2010 at 03:27:50PM -0500, Goldwyn Rodrigues wrote:
>> On Wed, Jun 23, 2010 at 2:05 PM, Sunil Mushran <sunil.mushran at oracle.com> wrote:
>> >>> kmalloc()s can fail. If this is just an int, why not just store it
>> >>> directly in d_fsdata. Add appropriate casts.
>> >>>
>> >>
>> >> This will cause compilation warnings for either x86_64 or i686 systems
>> >> depending on the data type we choose. I will do this anyways.
>> >>
>> >
>> > See if you can silence the warning. My main problem here is that
>> > we don't handle the error case. So if kmalloc() is seen as the best
>> > solution, go ahead use it, but do handle the ENOMEM case.
>> >
>>
>> Oh yes, changing the (function) variables to long should do it, since
>> long is the same size as pointer.
>> I will make the change and test it. Thanks.
>
>        You can use an int too.  Casting works.  That said, using an

Without warnings? this is on an x86_64 compile -

unsigned int gen = (unsigned int)dentry->d_fsdata;

/home/goldwyn/work/linux-2.6/fs/ocfs2/dcache.c: In function
‘ocfs2_dentry_revalidate’:
/home/goldwyn/work/linux-2.6/fs/ocfs2/dcache.c:69: warning: cast from
pointer to integer of different size

Changing it to a different cast type might help, but it would create
more confusion.

> unsigned long does not hurt.  Make sure you use unsigned long, as
> pointers are unsigned longs.  You'll still need to cast to/from.

Yes, I am using unsigned long.

-- 
Goldwyn