SUNRPC: Change return value type of .pc_encode

Returning an undecorated integer is an age-old trope, but it's
not clear (even to previous experts in this code) that the only
valid return values are 1 and 0. These functions do not return
a negative errno, rpc_stat value, or a positive length.

Document there are only two valid return values by having
.pc_encode return only true or false.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/lockd/xdr.c

@@ -313,13 +313,13 @@ nlmsvc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
  * Encode Reply results
  */
 
-int
+bool
 nlmsvc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
-	return 1;
+	return true;
 }
 
-int
+bool
 nlmsvc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
@@ -328,7 +328,7 @@ nlmsvc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 		svcxdr_encode_testrply(xdr, resp);
 }
 
-int
+bool
 nlmsvc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
@@ -337,18 +337,18 @@ nlmsvc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 		svcxdr_encode_stats(xdr, resp->status);
 }
 
-int
+bool
 nlmsvc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
 
 	if (!svcxdr_encode_cookie(xdr, &resp->cookie))
-		return 0;
+		return false;
 	if (!svcxdr_encode_stats(xdr, resp->status))
-		return 0;
+		return false;
 	/* sequence */
 	if (xdr_stream_encode_u32(xdr, 0) < 0)
-		return 0;
+		return false;
 
-	return 1;
+	return true;
 }

fs/lockd/xdr4.c

@@ -312,13 +312,13 @@ nlm4svc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
  * Encode Reply results
  */
 
-int
+bool
 nlm4svc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
-	return 1;
+	return true;
 }
 
-int
+bool
 nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
@@ -327,7 +327,7 @@ nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 		svcxdr_encode_testrply(xdr, resp);
 }
 
-int
+bool
 nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
@@ -336,18 +336,18 @@ nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 		svcxdr_encode_stats(xdr, resp->status);
 }
 
-int
+bool
 nlm4svc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nlm_res *resp = rqstp->rq_resp;
 
 	if (!svcxdr_encode_cookie(xdr, &resp->cookie))
-		return 0;
+		return false;
 	if (!svcxdr_encode_stats(xdr, resp->status))
-		return 0;
+		return false;
 	/* sequence */
 	if (xdr_stream_encode_u32(xdr, 0) < 0)
-		return 0;
+		return false;
 
-	return 1;
+	return true;
 }

fs/nfs/callback_xdr.c

@@ -67,9 +67,9 @@ static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
  * svc_process_common() looks for an XDR encoder to know when
  * not to drop a Reply.
  */
-static int nfs4_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
+static bool nfs4_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
-	return 1;
+	return true;
 }
 
 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len,

fs/nfsd/nfs2acl.c

@@ -240,7 +240,7 @@ nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
  */
 
 /* GETACL */
-static int
+static bool
 nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
@@ -280,7 +280,7 @@ nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 }
 
 /* ACCESS */
-static int
+static bool
 nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nfsd3_accessres *resp = rqstp->rq_resp;

fs/nfsd/nfs3acl.c

@@ -166,7 +166,7 @@ nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
  */
 
 /* GETACL */
-static int
+static bool
 nfs3svc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
@@ -178,14 +178,14 @@ nfs3svc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 	int w;
 
 	if (!svcxdr_encode_nfsstat3(xdr, resp->status))
-		return 0;
+		return false;
 	switch (resp->status) {
 	case nfs_ok:
 		inode = d_inode(dentry);
 		if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
-			return 0;
+			return false;
 		if (xdr_stream_encode_u32(xdr, resp->mask) < 0)
-			return 0;
+			return false;
 
 		base = (char *)xdr->p - (char *)head->iov_base;
 
@@ -194,7 +194,7 @@ nfs3svc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
 		while (w > 0) {
 			if (!*(rqstp->rq_next_page++))
-				return 0;
+				return false;
 			w -= PAGE_SIZE;
 		}
 
@@ -207,18 +207,18 @@ nfs3svc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 					  resp->mask & NFS_DFACL,
 					  NFS_ACL_DEFAULT);
 		if (n <= 0)
-			return 0;
+			return false;
 		break;
 	default:
 		if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
-			return 0;
+			return false;
 	}
 
-	return 1;
+	return true;
 }
 
 /* SETACL */
-static int
+static bool
 nfs3svc_encode_setaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
 {
 	struct nfsd3_attrstat *resp = rqstp->rq_resp;