[PATCH 2/2] nfsd: default to kernel default for minorversion 1

["J. Bruce Fields" <bfields@citi.umich.edu>]

The current kernel code should not be enabled by default, because it
does not yet attempt to be a conform completely to the rfc; for example,
some required pieces of protocol are missing.

Therefore the kernel defaults to leaving minorversion1 off.  When the
code matures sufficiently, that default will change.

That kernel default becomes meaningless if nfs-utils always explicitly
turns 4.1 on or off.  So, nfs-utils should by default do nothing.

Provide a --enable-experimental-v41-support option to turn it on
explicitly.  The option is intentionally spelled out (and has no short
equivalent), to help ensure that users know what they're getting into.

Once 4.1 defaults to on, that option will become unnecessary (and can
probably just be dropped from nfs-utils), and only the -N 4.1 option
will be necessary.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
---
 support/include/nfs/nfs.h |    3 ---
 utils/nfsd/nfsd.c         |   17 +++++++++++++----
 utils/nfsd/nfssvc.c       |   10 ++++------
 3 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/support/include/nfs/nfs.h b/support/include/nfs/nfs.h
index a64eb0a..824f604 100644
--- a/support/include/nfs/nfs.h
+++ b/support/include/nfs/nfs.h
@@ -13,9 +13,6 @@
 #define NFSD_MINVERS 2
 #define NFSD_MAXVERS 4
 
-#define NFSD_MINMINORVERS4 1
-#define NFSD_MAXMINORVERS4 1
-
 struct nfs_fh_len {
 	int		fh_size;
 	u_int8_t	fh_handle[NFS3_FHSIZE];
diff --git a/utils/nfsd/nfsd.c b/utils/nfsd/nfsd.c
index 1cda1e5..c72f73e 100644
--- a/utils/nfsd/nfsd.c
+++ b/utils/nfsd/nfsd.c
@@ -49,6 +49,7 @@ static struct option longopts[] =
 	{ "port", 1, 0, 'p' },
 	{ "debug", 0, 0, 'd' },
 	{ "syslog", 0, 0, 's' },
+	{ "enable-experimental-v41-support", 0, 0, 'X' },
 	{ NULL, 0, 0, 0 }
 };
 
@@ -103,7 +104,7 @@ main(int argc, char **argv)
 	char *p, *progname, *port;
 	char *haddr = NULL;
 	int	socket_up = 0;
-	int minorvers4 = NFSD_MAXMINORVERS4;	/* nfsv4 minor version */
+	int minorvers41 = 0;	/* nfsv4 minor version */
 	unsigned int versbits = NFSCTL_ALLBITS;
 	unsigned int protobits = NFSCTL_ALLBITS;
 	unsigned int proto4 = 0;
@@ -163,7 +164,12 @@ main(int argc, char **argv)
 			switch((c = strtol(optarg, &p, 0))) {
 			case 4:
 				if (*p == '.') {
-					minorvers4 = -atoi(p + 1);
+					int i = atoi(p+1);
+					if (i != 1) {
+						fprintf(stderr, "%s: unsupported minor version\n", optarg);
+						exit(1);
+					}
+					minorvers41 = -1;
 					break;
 				}
 			case 3:
@@ -185,6 +191,9 @@ main(int argc, char **argv)
 		case 'U':
 			NFSCTL_UDPUNSET(protobits);
 			break;
+		case 'X':
+			minorvers41 = 1;
+			break;
 		default:
 			fprintf(stderr, "Invalid argument: '%c'\n", c);
 		case 'h':
@@ -257,7 +266,7 @@ main(int argc, char **argv)
 	 * registered with rpcbind. Note that on older kernels w/o the right
 	 * interfaces, these are a no-op.
 	 */
-	nfssvc_setvers(versbits, minorvers4);
+	nfssvc_setvers(versbits, minorvers41);
  
 	error = nfssvc_set_sockets(AF_INET, proto4, haddr, port);
 	if (!error)
@@ -309,7 +318,7 @@ static void
 usage(const char *prog)
 {
 	fprintf(stderr, "Usage:\n"
-		"%s [-d|--debug] [-H hostname] [-p|-P|--port port] [-N|--no-nfs-version version ] [-s|--syslog] [-T|--no-tcp] [-U|--no-udp] nrservs\n", 
+		"%s [-d|--debug] [-H hostname] [-p|-P|--port port] [-N|--no-nfs-version version ] [-s|--syslog] [-T|--no-tcp] [-U|--no-udp] [--enable-experimental-v41-support] nrservs\n", 
 		prog);
 	exit(2);
 }
diff --git a/utils/nfsd/nfssvc.c b/utils/nfsd/nfssvc.c
index 7bbbaba..ec9446a 100644
--- a/utils/nfsd/nfssvc.c
+++ b/utils/nfsd/nfssvc.c
@@ -227,7 +227,7 @@ nfssvc_set_sockets(const int family, const unsigned int protobits,
 }
 
 void
-nfssvc_setvers(unsigned int ctlbits, int minorvers4)
+nfssvc_setvers(unsigned int ctlbits, int minorvers41)
 {
 	int fd, n, off;
 	char *ptr;
@@ -238,11 +238,9 @@ nfssvc_setvers(unsigned int ctlbits, int minorvers4)
 	if (fd < 0)
 		return;
 
-	n = minorvers4 >= 0 ? minorvers4 : -minorvers4;
-	if (n >= NFSD_MINMINORVERS4 && n <= NFSD_MAXMINORVERS4)
-		    off += snprintf(ptr+off, sizeof(buf) - off, "%c4.%d",
-				    minorvers4 > 0 ? '+' : '-',
-				    n);
+	if (minorvers41)
+		off += snprintf(ptr+off, sizeof(buf) - off, "%c4.1",
+				minorvers41 > 0 ? '+' : '-');
 	for (n = NFSD_MINVERS; n <= NFSD_MAXVERS; n++) {
 		if (NFSCTL_VERISSET(ctlbits, n))
 		    off += snprintf(ptr+off, sizeof(buf) - off, "+%d ", n);
-- 
1.6.3.3