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 <[e-mail]>
Signed-off-by: J. Bruce Fields <[e-mail]>

fs/nfsd/nfs2acl.c

···
 static __be32
 nfsacld_proc_null(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 
 	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
 out:
-	return resp->status;
+	return rpc_success;
 
 fail:
 	posix_acl_release(resp->acl_access);
···
 	   nfssvc_decode_setaclargs. */
 	posix_acl_release(argp->acl_access);
 	posix_acl_release(argp->acl_default);
-	return resp->status;
+	return rpc_success;
 
 out_drop_lock:
 	fh_unlock(fh);
···
 		goto out;
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 		goto out;
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	int n;
 	int w;
 
+	*p++ = resp->status;
 	if (resp->status != nfs_ok)
 		return xdr_ressize_check(rqstp, 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 = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
+out:
 	return xdr_ressize_check(rqstp, p);
 }
 
···
 {
 	struct nfsd3_accessres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status != nfs_ok)
-		return xdr_ressize_check(rqstp, p);
+		goto out;
 
 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
 	*p++ = htonl(resp->access);
+out:
 	return xdr_ressize_check(rqstp, p);
 }
 

fs/nfsd/nfs3acl.c

···
 static __be32
 nfsd3_proc_null(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 
 	/* resp->acl_{access,default} are released in nfs3svc_release_getacl. */
 out:
-	return resp->status;
+	return rpc_success;
 
 fail:
 	posix_acl_release(resp->acl_access);
···
 	   nfs3svc_decode_setaclargs. */
 	posix_acl_release(argp->acl_access);
 	posix_acl_release(argp->acl_default);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
 	struct dentry *dentry = resp->fh.fh_dentry;
 
+	*p++ = resp->status;
 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
 	if (resp->status == 0 && dentry && d_really_is_positive(dentry)) {
 		struct inode *inode = d_inode(dentry);
···
 {
 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
-
 	return xdr_ressize_check(rqstp, p);
 }
 

fs/nfsd/nfs3proc.c

···
 static __be32
 nfsd3_proc_null(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_setattr(rqstp, &resp->fh, &argp->attrs,
 				    argp->check_guard, argp->guardtime);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_lookup(rqstp, &resp->dirfh,
 				   argp->name, argp->len,
 				   &resp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	fh_copy(&resp->fh, &argp->fh);
 	resp->access = argp->access;
 	resp->status = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	fh_copy(&resp->fh, &argp->fh);
 	resp->len = NFS3_MAXPATHLEN;
 	resp->status = nfsd_readlink(rqstp, &resp->fh, argp->buffer, &resp->len);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
 				 rqstp->rq_vec, argp->vlen, &resp->count,
 				 &resp->eof);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 				  resp->committed, resp->verf);
 	resp->count = cnt;
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = do_nfsd_create(rqstp, dirfhp, argp->name, argp->len,
 				      attr, newfhp, argp->createmode,
 				      (u32 *)argp->verf, NULL, NULL);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_create(rqstp, &resp->dirfh, argp->name, argp->len,
 				   &argp->attrs, S_IFDIR, 0, &resp->fh);
 	fh_unlock(&resp->dirfh);
-	return resp->status;
+	return rpc_success;
 }
 
 static __be32
···
 				    argp->flen, argp->tname, &resp->fh);
 	kfree(argp->tname);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 				   &argp->attrs, type, rdev, &resp->fh);
 	fh_unlock(&resp->dirfh);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_unlink(rqstp, &resp->fh, -S_IFDIR,
 				   argp->name, argp->len);
 	fh_unlock(&resp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_unlink(rqstp, &resp->fh, S_IFDIR,
 				   argp->name, argp->len);
 	fh_unlock(&resp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 static __be32
···
 	fh_copy(&resp->tfh, &argp->tfh);
 	resp->status = nfsd_rename(rqstp, &resp->ffh, argp->fname, argp->flen,
 				   &resp->tfh, argp->tname, argp->tlen);
-	return resp->status;
+	return rpc_success;
 }
 
 static __be32
···
 	fh_copy(&resp->tfh, &argp->tfh);
 	resp->status = nfsd_link(rqstp, &resp->tfh, argp->tname, argp->tlen,
 				 &resp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 		resp->offset = NULL;
 	}
 
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	}
 
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 
 	resp->status = nfsd_statfs(rqstp, &argp->fh, &resp->stats, 0);
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	}
 
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	}
 
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_commit(rqstp, &resp->fh, argp->offset,
 				   argp->count, resp->verf);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 

fs/nfsd/nfs3xdr.c

···
 /*
  * XDR encode functions
  */
-/*
- * There must be an encoding function for void results so svc_process
- * will work properly.
- */
+
 int
 nfs3svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
 {
···
 {
 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status == 0) {
 		lease_get_mtime(d_inode(resp->fh.fh_dentry),
 				&resp->stat.mtime);
···
 {
 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_wcc_data(rqstp, p, &resp->fh);
 	return xdr_ressize_check(rqstp, p);
 }
···
 {
 	struct nfsd3_diropres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status == 0) {
 		p = encode_fh(p, &resp->fh);
 		p = encode_post_op_attr(rqstp, p, &resp->fh);
···
 {
 	struct nfsd3_accessres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_post_op_attr(rqstp, p, &resp->fh);
 	if (resp->status == 0)
 		*p++ = htonl(resp->access);
···
 {
 	struct nfsd3_readlinkres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_post_op_attr(rqstp, p, &resp->fh);
 	if (resp->status == 0) {
 		*p++ = htonl(resp->len);
···
 {
 	struct nfsd3_readres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_post_op_attr(rqstp, p, &resp->fh);
 	if (resp->status == 0) {
 		*p++ = htonl(resp->count);
···
 {
 	struct nfsd3_writeres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_wcc_data(rqstp, p, &resp->fh);
 	if (resp->status == 0) {
 		*p++ = htonl(resp->count);
···
 {
 	struct nfsd3_diropres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status == 0) {
 		*p++ = xdr_one;
 		p = encode_fh(p, &resp->fh);
···
 {
 	struct nfsd3_renameres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_wcc_data(rqstp, p, &resp->ffh);
 	p = encode_wcc_data(rqstp, p, &resp->tfh);
 	return xdr_ressize_check(rqstp, p);
···
 {
 	struct nfsd3_linkres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_post_op_attr(rqstp, p, &resp->fh);
 	p = encode_wcc_data(rqstp, p, &resp->tfh);
 	return xdr_ressize_check(rqstp, p);
···
 {
 	struct nfsd3_readdirres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_post_op_attr(rqstp, p, &resp->fh);
 
 	if (resp->status == 0) {
···
 	struct kstatfs	*s = &resp->stats;
 	u64		bs = s->f_bsize;
 
+	*p++ = resp->status;
 	*p++ = xdr_zero;	/* no post_op_attr */
 
 	if (resp->status == 0) {
···
 {
 	struct nfsd3_fsinfores *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	*p++ = xdr_zero;	/* no post_op_attr */
 
 	if (resp->status == 0) {
···
 {
 	struct nfsd3_commitres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	p = encode_wcc_data(rqstp, p, &resp->fh);
 	/* Write verifier */
 	if (resp->status == 0) {

fs/nfsd/nfs4proc.c

···
 static __be32
 nfsd4_proc_null(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 static inline void nfsd4_increment_op_stats(u32 opnum)
···
 		nfsd4_increment_op_stats(op->opnum);
 	}
 
-	cstate->status = status;
 	fh_put(current_fh);
 	fh_put(save_fh);
 	BUG_ON(cstate->replay_owner);
 out:
+	cstate->status = status;
 	/* Reset deferral mechanism for RPC deferrals */
 	set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
-	dprintk("nfsv4 compound returned %d\n", ntohl(status));
-	return status;
+	return rpc_success;
 }
 
 #define op_encode_hdr_size		(2)

fs/nfsd/nfs4xdr.c

···
 int
 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
 {
-	/*
-	 * All that remains is to write the tag and operation count...
-	 */
 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
 	struct xdr_buf *buf = resp->xdr.buf;
 
 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
 				 buf->tail[0].iov_len);
+
+	*p = resp->cstate.status;
 
 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
 

fs/nfsd/nfsproc.c

···
 static __be32
 nfsd_proc_null(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 		goto out;
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 
 		resp->status = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
 		if (resp->status != nfs_ok)
-			return resp->status;
+			goto out;
 
 		if (delta < 0)
 			delta = -delta;
···
 
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /* Obsolete, replaced by MNTPROC_MNT. */
 static __be32
 nfsd_proc_root(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_readlink(rqstp, &argp->fh, argp->buffer, &resp->len);
 
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 				 rqstp->rq_vec, argp->vlen,
 				 &resp->count,
 				 &eof);
-	if (resp->status != nfs_ok)
-		goto out;
-
-	resp->status = fh_getattr(&resp->fh, &resp->stat);
-out:
-	return resp->status;
+	if (resp->status == nfs_ok)
+		resp->status = fh_getattr(&resp->fh, &resp->stat);
+	else if (resp->status == nfserr_jukebox)
+		return rpc_drop_reply;
+	return rpc_success;
 }
 
 /* Reserved */
 static __be32
 nfsd_proc_writecache(struct svc_rqst *rqstp)
 {
-	return nfs_ok;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_write(rqstp, fh_copy(&resp->fh, &argp->fh),
 				  argp->offset, rqstp->rq_vec, nvecs,
 				  &cnt, NFS_DATA_SYNC, NULL);
-	if (resp->status != nfs_ok)
-		goto out;
-
-	resp->status = fh_getattr(&resp->fh, &resp->stat);
+	if (resp->status == nfs_ok)
+		resp->status = fh_getattr(&resp->fh, &resp->stat);
+	else if (resp->status == nfserr_jukebox)
+		return rpc_drop_reply;
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 		goto out;
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 static __be32
 nfsd_proc_remove(struct svc_rqst *rqstp)
 {
 	struct nfsd_diropargs *argp = rqstp->rq_argp;
-	__be32	nfserr;
+	struct nfsd_stat *resp = rqstp->rq_resp;
 
 	dprintk("nfsd: REMOVE   %s %.*s\n", SVCFH_fmt(&argp->fh),
 		argp->len, argp->name);
 
 	/* Unlink. -SIFDIR means file must not be a directory */
-	nfserr = nfsd_unlink(rqstp, &argp->fh, -S_IFDIR, argp->name, argp->len);
+	resp->status = nfsd_unlink(rqstp, &argp->fh, -S_IFDIR,
+				   argp->name, argp->len);
 	fh_put(&argp->fh);
-	return nfserr;
+	return rpc_success;
 }
 
 static __be32
 nfsd_proc_rename(struct svc_rqst *rqstp)
 {
 	struct nfsd_renameargs *argp = rqstp->rq_argp;
-	__be32	nfserr;
+	struct nfsd_stat *resp = rqstp->rq_resp;
 
 	dprintk("nfsd: RENAME   %s %.*s -> \n",
 		SVCFH_fmt(&argp->ffh), argp->flen, argp->fname);
 	dprintk("nfsd:        ->  %s %.*s\n",
 		SVCFH_fmt(&argp->tfh), argp->tlen, argp->tname);
 
-	nfserr = nfsd_rename(rqstp, &argp->ffh, argp->fname, argp->flen,
-				    &argp->tfh, argp->tname, argp->tlen);
+	resp->status = nfsd_rename(rqstp, &argp->ffh, argp->fname, argp->flen,
+				   &argp->tfh, argp->tname, argp->tlen);
 	fh_put(&argp->ffh);
 	fh_put(&argp->tfh);
-	return nfserr;
+	return rpc_success;
 }
 
 static __be32
 nfsd_proc_link(struct svc_rqst *rqstp)
 {
 	struct nfsd_linkargs *argp = rqstp->rq_argp;
-	__be32	nfserr;
+	struct nfsd_stat *resp = rqstp->rq_resp;
 
 	dprintk("nfsd: LINK     %s ->\n",
 		SVCFH_fmt(&argp->ffh));
···
 		argp->tlen,
 		argp->tname);
 
-	nfserr = nfsd_link(rqstp, &argp->tfh, argp->tname, argp->tlen,
-				  &argp->ffh);
+	resp->status = nfsd_link(rqstp, &argp->tfh, argp->tname, argp->tlen,
+				 &argp->ffh);
 	fh_put(&argp->ffh);
 	fh_put(&argp->tfh);
-	return nfserr;
+	return rpc_success;
 }
 
 static __be32
 nfsd_proc_symlink(struct svc_rqst *rqstp)
 {
 	struct nfsd_symlinkargs *argp = rqstp->rq_argp;
+	struct nfsd_stat *resp = rqstp->rq_resp;
 	struct svc_fh	newfh;
-	__be32		nfserr;
 
 	if (argp->tlen > NFS_MAXPATHLEN) {
-		nfserr = nfserr_nametoolong;
+		resp->status = nfserr_nametoolong;
 		goto out;
 	}
 
···
 						page_address(rqstp->rq_arg.pages[0]),
 						argp->tlen);
 	if (IS_ERR(argp->tname)) {
-		nfserr = nfserrno(PTR_ERR(argp->tname));
+		resp->status = nfserrno(PTR_ERR(argp->tname));
 		goto out;
 	}
 
···
 		argp->tlen, argp->tname);
 
 	fh_init(&newfh, NFS_FHSIZE);
-	nfserr = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen,
-						 argp->tname, &newfh);
+	resp->status = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen,
+				    argp->tname, &newfh);
 
 	kfree(argp->tname);
 	fh_put(&argp->ffh);
 	fh_put(&newfh);
 out:
-	return nfserr;
+	return rpc_success;
 }
 
 /*
···
 
 	resp->status = fh_getattr(&resp->fh, &resp->stat);
 out:
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 nfsd_proc_rmdir(struct svc_rqst *rqstp)
 {
 	struct nfsd_diropargs *argp = rqstp->rq_argp;
-	__be32	nfserr;
+	struct nfsd_stat *resp = rqstp->rq_resp;
 
 	dprintk("nfsd: RMDIR    %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);
 
-	nfserr = nfsd_unlink(rqstp, &argp->fh, S_IFDIR, argp->name, argp->len);
+	resp->status = nfsd_unlink(rqstp, &argp->fh, S_IFDIR,
+				   argp->name, argp->len);
 	fh_put(&argp->fh);
-	return nfserr;
+	return rpc_success;
 }
 
 /*
···
 		*resp->offset = htonl(offset);
 
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 	resp->status = nfsd_statfs(rqstp, &argp->fh, &resp->stats,
 				   NFSD_MAY_BYPASS_GSS_ON_ROOT);
 	fh_put(&argp->fh);
-	return resp->status;
+	return rpc_success;
 }
 
 /*
···
 		.pc_argsize = sizeof(struct nfsd_void),
 		.pc_ressize = sizeof(struct nfsd_void),
 		.pc_cachetype = RC_NOCACHE,
-		.pc_xdrressize = ST,
+		.pc_xdrressize = 0,
 	},
 	[NFSPROC_GETATTR] = {
 		.pc_func = nfsd_proc_getattr,
···
 		.pc_argsize = sizeof(struct nfsd_void),
 		.pc_ressize = sizeof(struct nfsd_void),
 		.pc_cachetype = RC_NOCACHE,
-		.pc_xdrressize = ST,
+		.pc_xdrressize = 0,
 	},
 	[NFSPROC_LOOKUP] = {
 		.pc_func = nfsd_proc_lookup,
···
 		.pc_argsize = sizeof(struct nfsd_void),
 		.pc_ressize = sizeof(struct nfsd_void),
 		.pc_cachetype = RC_NOCACHE,
-		.pc_xdrressize = ST,
+		.pc_xdrressize = 0,
 	},
 	[NFSPROC_WRITE] = {
 		.pc_func = nfsd_proc_write,
···
 	[NFSPROC_REMOVE] = {
 		.pc_func = nfsd_proc_remove,
 		.pc_decode = nfssvc_decode_diropargs,
-		.pc_encode = nfssvc_encode_void,
+		.pc_encode = nfssvc_encode_stat,
 		.pc_argsize = sizeof(struct nfsd_diropargs),
-		.pc_ressize = sizeof(struct nfsd_void),
+		.pc_ressize = sizeof(struct nfsd_stat),
 		.pc_cachetype = RC_REPLSTAT,
 		.pc_xdrressize = ST,
 	},
 	[NFSPROC_RENAME] = {
 		.pc_func = nfsd_proc_rename,
 		.pc_decode = nfssvc_decode_renameargs,
-		.pc_encode = nfssvc_encode_void,
+		.pc_encode = nfssvc_encode_stat,
 		.pc_argsize = sizeof(struct nfsd_renameargs),
-		.pc_ressize = sizeof(struct nfsd_void),
+		.pc_ressize = sizeof(struct nfsd_stat),
 		.pc_cachetype = RC_REPLSTAT,
 		.pc_xdrressize = ST,
 	},
 	[NFSPROC_LINK] = {
 		.pc_func = nfsd_proc_link,
 		.pc_decode = nfssvc_decode_linkargs,
-		.pc_encode = nfssvc_encode_void,
+		.pc_encode = nfssvc_encode_stat,
 		.pc_argsize = sizeof(struct nfsd_linkargs),
-		.pc_ressize = sizeof(struct nfsd_void),
+		.pc_ressize = sizeof(struct nfsd_stat),
 		.pc_cachetype = RC_REPLSTAT,
 		.pc_xdrressize = ST,
 	},
 	[NFSPROC_SYMLINK] = {
 		.pc_func = nfsd_proc_symlink,
 		.pc_decode = nfssvc_decode_symlinkargs,
-		.pc_encode = nfssvc_encode_void,
+		.pc_encode = nfssvc_encode_stat,
 		.pc_argsize = sizeof(struct nfsd_symlinkargs),
-		.pc_ressize = sizeof(struct nfsd_void),
+		.pc_ressize = sizeof(struct nfsd_stat),
 		.pc_cachetype = RC_REPLSTAT,
 		.pc_xdrressize = ST,
 	},
···
 	[NFSPROC_RMDIR] = {
 		.pc_func = nfsd_proc_rmdir,
 		.pc_decode = nfssvc_decode_diropargs,
-		.pc_encode = nfssvc_encode_void,
+		.pc_encode = nfssvc_encode_stat,
 		.pc_argsize = sizeof(struct nfsd_diropargs),
-		.pc_ressize = sizeof(struct nfsd_void),
+		.pc_ressize = sizeof(struct nfsd_stat),
 		.pc_cachetype = RC_REPLSTAT,
 		.pc_xdrressize = ST,
 	},

fs/nfsd/nfssvc.c

···
 	return 0;
 }
 
-static __be32 map_new_errors(u32 vers, __be32 nfserr)
-{
-	if (nfserr == nfserr_jukebox && vers == 2)
-		return nfserr_dropit;
-	return nfserr;
-}
-
 /*
  * A write procedure can have a large argument, and a read procedure can
  * have a large reply, but no NFSv2 or NFSv3 procedure has argument and
···
 	const struct svc_procedure *proc = rqstp->rq_procinfo;
 	struct kvec *argv = &rqstp->rq_arg.head[0];
 	struct kvec *resv = &rqstp->rq_res.head[0];
-	__be32 nfserr, *nfserrp;
+	__be32 *p;
 
 	dprintk("nfsd_dispatch: vers %d proc %d\n",
 				rqstp->rq_vers, rqstp->rq_proc);
···
 	 * Need to grab the location to store the status, as
 	 * NFSv4 does some encoding while processing
 	 */
-	nfserrp = resv->iov_base + resv->iov_len;
+	p = resv->iov_base + resv->iov_len;
 	resv->iov_len += sizeof(__be32);
 
-	nfserr = proc->pc_func(rqstp);
-	nfserr = map_new_errors(rqstp->rq_vers, nfserr);
-	if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags))
+	*statp = proc->pc_func(rqstp);
+	if (*statp == rpc_drop_reply || test_bit(RQ_DROPME, &rqstp->rq_flags))
 		goto out_update_drop;
 
-	if (rqstp->rq_proc != 0)
-		*nfserrp++ = nfserr;
-
-	if (!proc->pc_encode(rqstp, nfserrp))
+	if (!proc->pc_encode(rqstp, p))
 		goto out_encode_err;
 
 	nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);

fs/nfsd/nfsxdr.c

···
 }
 
 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);
 }
 
···
 {
 	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);
 }
 
···
 {
 	struct nfsd_readlinkres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status != nfs_ok)
 		return xdr_ressize_check(rqstp, p);
 
···
 {
 	struct nfsd_readres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status != nfs_ok)
 		return xdr_ressize_check(rqstp, p);
 
···
 {
 	struct nfsd_readdirres *resp = rqstp->rq_resp;
 
+	*p++ = resp->status;
 	if (resp->status != nfs_ok)
 		return xdr_ressize_check(rqstp, 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);
 

fs/nfsd/xdr.h

···
 	__be32 *		buffer;
 };
 
+struct nfsd_stat {
+	__be32			status;
+};
+
 struct nfsd_attrstat {
 	__be32			status;
 	struct svc_fh		fh;
···
 int nfssvc_decode_symlinkargs(struct svc_rqst *, __be32 *);
 int nfssvc_decode_readdirargs(struct svc_rqst *, __be32 *);
 int nfssvc_encode_void(struct svc_rqst *, __be32 *);
+int nfssvc_encode_stat(struct svc_rqst *, __be32 *);
 int nfssvc_encode_attrstat(struct svc_rqst *, __be32 *);
 int nfssvc_encode_diropres(struct svc_rqst *, __be32 *);
 int nfssvc_encode_readlinkres(struct svc_rqst *, __be32 *);