+/*
+ * Reconstruct the mount option string based on a portmapper probe
+ * of the server. Returns one if the server's portmapper returned
+ * something we can use, otherwise zero.
+ *
+ * To handle version and transport protocol fallback properly, we
+ * need to parse some of the mount options in order to set up a
+ * portmap probe. Mount options that nfs_rewrite_pmap_mount_options()
+ * doesn't recognize are left alone.
+ *
+ * Returns TRUE if rewriting was successful; otherwise
+ * FALSE is returned if some failure occurred.
+ */
+static int
+nfs_rewrite_pmap_mount_options(struct mount_options *options)
+{
+ union nfs_sockaddr nfs_address;
+ struct sockaddr *nfs_saddr = &nfs_address.sa;
+ socklen_t nfs_salen = sizeof(nfs_address);
+ struct pmap nfs_pmap;
+ union nfs_sockaddr mnt_address;
+ struct sockaddr *mnt_saddr = &mnt_address.sa;
+ socklen_t mnt_salen = sizeof(mnt_address);
+ struct pmap mnt_pmap;
+ char *option;
+
+ /*
+ * Skip option negotiation for proto=rdma mounts.
+ */
+ option = po_get(options, "proto");
+ if (option && strcmp(option, "rdma") == 0)
+ goto out;
+
+ /*
+ * Extract just the options needed to contact server.
+ * Bail now if any of these have bad values.
+ */
+ if (!nfs_extract_server_addresses(options, nfs_saddr, &nfs_salen,
+ mnt_saddr, &mnt_salen)) {
+ errno = EINVAL;
+ return 0;
+ }
+ if (!nfs_options2pmap(options, &nfs_pmap, &mnt_pmap)) {
+ errno = EINVAL;
+ return 0;
+ }
+
+ /*
+ * The kernel NFS client doesn't support changing the RPC
+ * program number for these services, so force the value of
+ * these fields before probing the server's ports.
+ */
+ nfs_pmap.pm_prog = NFS_PROGRAM;
+ mnt_pmap.pm_prog = MOUNTPROG;
+
+ /*
+ * If the server's rpcbind service isn't available, we can't
+ * negotiate. Bail now if we can't contact it.
+ */
+ if (!nfs_probe_bothports(mnt_saddr, mnt_salen, &mnt_pmap,
+ nfs_saddr, nfs_salen, &nfs_pmap)) {
+ errno = ESPIPE;
+ if (rpc_createerr.cf_stat == RPC_PROGNOTREGISTERED)
+ errno = EOPNOTSUPP;
+ else if (rpc_createerr.cf_error.re_errno != 0)
+ errno = rpc_createerr.cf_error.re_errno;
+ return 0;
+ }
+
+ if (!nfs_construct_new_options(options, nfs_saddr, &nfs_pmap,
+ mnt_saddr, &mnt_pmap)) {
+ if (rpc_createerr.cf_stat == RPC_UNKNOWNPROTO)
+ errno = EPROTONOSUPPORT;
+ else
+ errno = EINVAL;
+ return 0;
+ }
+
+out:
+ errno = 0;