Re: [PATCH] NFS: simplify check for freeing cn_resp

[Tom Rix]

On 1/16/22 7:47 AM, Trond Myklebust wrote:
> Hi Tom,
>
> On Sun, 2022-01-16 at 06:43 -0800, trix@xxxxxxxxxx wrote:
> > From: Tom Rix <trix@xxxxxxxxxx>
> >
> > nfs42_files_from_same_server() is called to check if freeing
> > cn_resp is required.  Instead of calling a function, check
> > the pointer.
> >
> > Signed-off-by: Tom Rix <trix@xxxxxxxxxx>
> > ---
> >   fs/nfs/nfs4file.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
> > index e79ae4cbc395e..677631ea4cfb3 100644
> > --- a/fs/nfs/nfs4file.c
> > +++ b/fs/nfs/nfs4file.c
> > @@ -180,7 +180,7 @@ static ssize_t __nfs4_copy_file_range(struct file
> > *file_in, loff_t pos_in,
> >          ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out,
> > count,
> >                                  nss, cnrs, sync);
> >   out:
> > -       if (!nfs42_files_from_same_server(file_in, file_out))
> > +       if (cn_resp)
> >                  kfree(cn_resp);
> The kernel convention in these circumstances is to just skip the NULL
> pointer check, since kfree() does that anyway.

Yes. I'll respin.

Tom

> >          if (ret == -EAGAIN)
> >                  goto retry;