+static int nfs_set_version(struct nfsmount_info *mi)
+{
+ if (!nfs_nfs_version(mi->options, &mi->version))
+ return 0;
+
+ if (strncmp(mi->type, "nfs4", 4) == 0)
+ mi->version = 4;
+
+ /*
+ * Before 2.6.32, the kernel NFS client didn't
+ * support "-t nfs vers=4" mounts, so NFS version
+ * 4 cannot be included when autonegotiating
+ * while running on those kernels.
+ */
+ if (mi->version == 0 &&
+ linux_version_code() <= MAKE_VERSION(2, 6, 31))
+ mi->version = 3;
+
+ /*
+ * If we still don't know, check for version-specific
+ * mount options.
+ */
+ if (mi->version == 0) {
+ if (po_contains(mi->options, "mounthost") ||
+ po_contains(mi->options, "mountaddr") ||
+ po_contains(mi->options, "mountvers") ||
+ po_contains(mi->options, "mountproto"))
+ mi->version = 3;
+ }
+
+ /*
+ * If enabled, see if the default version was
+ * set in the config file
+ */
+ nfs_default_version(mi);
+
+ return 1;
+}
+
+/*
+ * Set up mandatory non-version specific NFS mount options.
+ *
+ * Returns 1 if successful; otherwise zero.
+ */
+static int nfs_validate_options(struct nfsmount_info *mi)
+{
+ struct addrinfo hint = {
+ .ai_protocol = (int)IPPROTO_UDP,
+ };
+ sa_family_t family;
+ int error;
+
+ if (!nfs_parse_devname(mi->spec, &mi->hostname, NULL))
+ return 0;
+
+ if (!nfs_nfs_proto_family(mi->options, &family))
+ return 0;
+
+ hint.ai_family = (int)family;
+ error = getaddrinfo(mi->hostname, NULL, &hint, &mi->address);
+ if (error != 0) {
+ nfs_error(_("%s: Failed to resolve server %s: %s"),
+ progname, mi->hostname, gai_strerror(error));
+ mi->address = NULL;
+ return 0;
+ }
+
+ if (!nfs_set_version(mi))
+ return 0;
+
+ if (!nfs_append_sloppy_option(mi->options))
+ return 0;
+
+ if (!nfs_append_addr_option(mi->address->ai_addr,
+ mi->address->ai_addrlen, mi->options))
+ return 0;
+
+ return 1;
+}
+
+/*
+ * Get NFS/mnt server addresses from mount options
+ *
+ * Returns 1 and fills in @nfs_saddr, @nfs_salen, @mnt_saddr, and @mnt_salen
+ * if all goes well; otherwise zero.
+ */
+static int nfs_extract_server_addresses(struct mount_options *options,
+ struct sockaddr *nfs_saddr,
+ socklen_t *nfs_salen,
+ struct sockaddr *mnt_saddr,
+ socklen_t *mnt_salen)
+{
+ char *option;
+
+ option = po_get(options, "addr");
+ if (option == NULL)
+ return 0;
+ if (!nfs_string_to_sockaddr(option, nfs_saddr, nfs_salen))
+ return 0;
+
+ option = po_get(options, "mountaddr");
+ if (option == NULL) {
+ memcpy(mnt_saddr, nfs_saddr, *nfs_salen);
+ *mnt_salen = *nfs_salen;
+ } else if (!nfs_string_to_sockaddr(option, mnt_saddr, mnt_salen))
+ return 0;
+
+ return 1;
+}
+
+static int nfs_construct_new_options(struct mount_options *options,
+ struct sockaddr *nfs_saddr,
+ struct pmap *nfs_pmap,
+ struct sockaddr *mnt_saddr,
+ struct pmap *mnt_pmap)
+{
+ char new_option[64];
+ char *netid;
+
+ po_remove_all(options, "nfsprog");
+ po_remove_all(options, "mountprog");
+
+ po_remove_all(options, "v2");
+ po_remove_all(options, "v3");
+ po_remove_all(options, "vers");
+ po_remove_all(options, "nfsvers");