NFSD: Hoist status code encoding into XDR encoder functions
The original intent was presumably to reduce code duplication. The
trade-off was:
- No support for an NFSD proc function returning a non-success
RPC accept_stat value.
- No support for void NFS replies to non-NULL procedures.
- Everyone pays for the deduplication with a few extra conditional
branches in a hot path.
In addition, nfsd_dispatch() leaves *statp uninitialized in the
success path, unlike svc_generic_dispatch().
Address all of these problems by moving the logic for encoding
the NFS status code into the NFS XDR encoders themselves. Then
update the NFS .pc_func methods to return an RPC accept_stat
value.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index 952e71c..8a288c8 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -430,14 +430,24 @@ nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p)
}
int
+nfssvc_encode_stat(struct svc_rqst *rqstp, __be32 *p)
+{
+ struct nfsd_stat *resp = rqstp->rq_resp;
+
+ *p++ = resp->status;
+ return xdr_ressize_check(rqstp, p);
+}
+
+int
nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_attrstat *resp = rqstp->rq_resp;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
- return xdr_ressize_check(rqstp, p);
-
+ goto out;
p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
+out:
return xdr_ressize_check(rqstp, p);
}
@@ -446,11 +456,12 @@ nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_diropres *resp = rqstp->rq_resp;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
- return xdr_ressize_check(rqstp, p);
-
+ goto out;
p = encode_fh(p, &resp->fh);
p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
+out:
return xdr_ressize_check(rqstp, p);
}
@@ -459,6 +470,7 @@ nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_readlinkres *resp = rqstp->rq_resp;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
return xdr_ressize_check(rqstp, p);
@@ -479,6 +491,7 @@ nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_readres *resp = rqstp->rq_resp;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
return xdr_ressize_check(rqstp, p);
@@ -502,6 +515,7 @@ nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_readdirres *resp = rqstp->rq_resp;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
return xdr_ressize_check(rqstp, p);
@@ -520,6 +534,7 @@ nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p)
struct nfsd_statfsres *resp = rqstp->rq_resp;
struct kstatfs *stat = &resp->stats;
+ *p++ = resp->status;
if (resp->status != nfs_ok)
return xdr_ressize_check(rqstp, p);