NFS: Do some tidying of the parsing code

Do some tidying of the parsing code, including:

 (*) Returning 0/error rather than true/false.

 (*) Putting the nfs_fs_context pointer first in some arg lists.

 (*) Unwrap some lines that will now fit on one line.

 (*) Provide unioned sockaddr/sockaddr_storage fields to avoid casts.

 (*) nfs_parse_devname() can paste its return values directly into the
     nfs_fs_context struct as that's where the caller puts them.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/internal.h

@@ -82,11 +82,11 @@ struct nfs_client_initdata {
  * In-kernel mount arguments
  */
 struct nfs_fs_context {
-	int			flags;
+	unsigned int		flags;		/* NFS{,4}_MOUNT_* flags */
 	unsigned int		rsize, wsize;
 	unsigned int		timeo, retrans;
-	unsigned int		acregmin, acregmax,
-				acdirmin, acdirmax;
+	unsigned int		acregmin, acregmax;
+	unsigned int		acdirmin, acdirmax;
 	unsigned int		namlen;
 	unsigned int		options;
 	unsigned int		bsize;
@@ -102,7 +102,10 @@ struct nfs_fs_context {
 	bool			sloppy;
 
 	struct {
-		struct sockaddr_storage	address;
+		union {
+			struct sockaddr	address;
+			struct sockaddr_storage	_address;
+		};
 		size_t			addrlen;
 		char			*hostname;
 		u32			version;
@@ -111,7 +114,10 @@ struct nfs_fs_context {
 	} mount_server;
 
 	struct {
-		struct sockaddr_storage	address;
+		union {
+			struct sockaddr	address;
+			struct sockaddr_storage	_address;
+		};
 		size_t			addrlen;
 		char			*hostname;
 		char			*export_path;

fs/nfs/super.c

@@ -816,7 +816,7 @@ static int nfs_request_mount(struct nfs_fs_context *cfg,
 	/*
 	 * Construct the mount server's address.
 	 */
-	if (cfg->mount_server.address.ss_family == AF_UNSPEC) {
+	if (cfg->mount_server.address.sa_family == AF_UNSPEC) {
 		memcpy(request.sap, &cfg->nfs_server.address,
 		       cfg->nfs_server.addrlen);
 		cfg->mount_server.addrlen = cfg->nfs_server.addrlen;