On Sun, Jun 30, 2024 at 10:49:51AM -0400, Chuck Lever wrote:
> On Sat, Jun 29, 2024 at 06:18:42PM -0400, Chuck Lever wrote:
> > > +
> > > + /* nfs_fh -> svc_fh */
> > > + if (nfs_fh->size > NFS4_FHSIZE) {
> > > + status = -EINVAL;
> > > + goto out;
> > > + }
> > > + fh_init(&fh, NFS4_FHSIZE);
> > > + fh.fh_handle.fh_size = nfs_fh->size;
> > > + memcpy(fh.fh_handle.fh_raw, nfs_fh->data, nfs_fh->size);
> > > +
> > > + if (fmode & FMODE_READ)
> > > + mayflags |= NFSD_MAY_READ;
> > > + if (fmode & FMODE_WRITE)
> > > + mayflags |= NFSD_MAY_WRITE;
> > > +
> > > + beres = nfsd_file_acquire(rqstp, &fh, mayflags, &nf);
> > > + if (beres) {
> > > + status = nfs_stat_to_errno(be32_to_cpu(beres));
> > > + goto out_fh_put;
> > > + }
> >
> > So I'm wondering whether just calling fh_verify() and then
> > nfsd_open_verified() would be simpler and/or good enough here. Is
> > there a strong reason to use the file cache for locally opened
> > files? Jeff, any thoughts?
>
> > Will there be writeback ramifications for
> > doing this? Maybe we need a comment here explaining how these files
> > are garbage collected (just an fput by the local I/O client, I would
> > guess).
>
> OK, going back to this: Since right here we immediately call
>
> nfsd_file_put(nf);
>
> There are no writeback ramifications nor any need to comment about
> garbage collection. But this still seems like a lot of (possibly
> unnecessary) overhead for simply obtaining a struct file.
Easy enough change, probably best to avoid the filecache but would like
to verify with Jeff before switching:
diff --git a/fs/nfsd/localio.c b/fs/nfsd/localio.c
index 1d6508aa931e..85ebf63789fb 100644
--- a/fs/nfsd/localio.c
+++ b/fs/nfsd/localio.c
@@ -197,7 +197,6 @@ int nfsd_open_local_fh(struct net *cl_nfssvc_net,
const struct cred *save_cred;
struct svc_rqst *rqstp;
struct svc_fh fh;
- struct nfsd_file *nf;
__be32 beres;
if (nfs_fh->size > NFS4_FHSIZE)
@@ -235,13 +234,12 @@ int nfsd_open_local_fh(struct net *cl_nfssvc_net,
if (fmode & FMODE_WRITE)
mayflags |= NFSD_MAY_WRITE;
- beres = nfsd_file_acquire(rqstp, &fh, mayflags, &nf);
+ beres = fh_verify(rqstp, &fh, S_IFREG, mayflags);
if (beres) {
status = nfs_stat_to_errno(be32_to_cpu(beres));
goto out_fh_put;
}
- *pfilp = get_file(nf->nf_file);
- nfsd_file_put(nf);
+ status = nfsd_open_verified(rqstp, &fh, mayflags, pfilp);
out_fh_put:
fh_put(&fh);
nfsd_local_fakerqst_destroy(rqstp);
Mike
