[PATCH v2 0/6] mount.nfs default version

[PATCH v2 0/6] mount.nfs default version

[Benjamin Coddington]

Here's the work posted yesterday broken out a bit with an addition of
enabling nfsmount.conf by default, and the change to autonegotiate starting
with version 4.2 (instead of 4.0) when no version is specified in either
config or mount option.

Benjamin Coddington (6):
  mount.nfs: default enable mount config file (nfsmount.conf)
  mount.nfs: fix a comment typo in parse options
  mount.nfs: parse options - add helper po_contains_prefix
  mount.nfs: Add struct nfs_version and generalize version parsing
  nfsmount.conf: Always parse versions
  mount.nfs: configurable minor version defaults

 configure.ac             |    8 +-
 utils/mount/configfile.c |   36 +-----------
 utils/mount/network.c    |  122 ++++++++++++++++++-------------------
 utils/mount/network.h    |   15 ++++-
 utils/mount/nfsumount.c  |    4 +-
 utils/mount/parse_opt.c  |   26 ++++++++-
 utils/mount/parse_opt.h  |    2 +
 utils/mount/stropts.c    |  150 +++++++++++++++++++++++++++++++---------------
 8 files changed, 209 insertions(+), 154 deletions(-)

[PATCH 1/6] mount.nfs: default enable mount config file (nfsmount.conf)

[Benjamin Coddington]

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 configure.ac |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index e3af723..c13e7ee 100644
--- a/configure.ac
+++ b/configure.ac
@@ -178,8 +178,10 @@ if test "$enable_mount" = yes; then
 	[AC_HELP_STRING([--enable-mountconfig],
                         [enable mount to use a configuration file])],
 	mountconfig=$enableval,
-	mountconfig=no)
-	if test "$enable_mountconfig" = yes; then
+	mountconfig=yes)
+	if test "$enable_mountconfig" = no; then
+		enable_mountconfig=
+	else
 		AC_DEFINE(MOUNT_CONFIG, 1, 
 			[Define this if you want mount to read a configuration file])
 		AC_ARG_WITH(mountfile,
@@ -191,8 +193,6 @@ if test "$enable_mount" = yes; then
 		AC_SUBST(mountfile)
 		AC_DEFINE_UNQUOTED(MOUNTOPTS_CONFFILE, "$mountfile", 
 			[This defines the location of the NFS mount configuration file])
-	else
-		enable_mountconfig=
 	fi
 	AC_SUBST(enable_mountconfig)
 	AM_CONDITIONAL(MOUNT_CONFIG, [test "$enable_mountconfig" = "yes"])
-- 
1.7.1

[PATCH 2/6] mount.nfs: fix a comment typo in parse options

[Benjamin Coddington]

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 utils/mount/parse_opt.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/utils/mount/parse_opt.c b/utils/mount/parse_opt.c
index 75a0daa..342e210 100644
--- a/utils/mount/parse_opt.c
+++ b/utils/mount/parse_opt.c
@@ -391,7 +391,7 @@ po_return_t po_append(struct mount_options *options, char *str)
 }
 
 /**
- * po_contains - check for presense of an option in a group
+ * po_contains - check for presence of an option in a group
  * @options: pointer to mount options
  * @keyword: pointer to a C string containing option keyword for which to search
  *
-- 
1.7.1

[PATCH 3/6] mount.nfs: parse options - add helper po_contains_prefix

[Benjamin Coddington]

The version options (v2,v4,v4.2) may increase in the future, but they have
a predictable prefix.  Add a parse option helper to locate and return these
options by prefix so that a future increment of version does not require the
addition of strings to a search table.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 utils/mount/parse_opt.c |   24 ++++++++++++++++++++++++
 utils/mount/parse_opt.h |    2 ++
 2 files changed, 26 insertions(+), 0 deletions(-)

diff --git a/utils/mount/parse_opt.c b/utils/mount/parse_opt.c
index 342e210..7ba61c4 100644
--- a/utils/mount/parse_opt.c
+++ b/utils/mount/parse_opt.c
@@ -410,6 +410,30 @@ po_found_t po_contains(struct mount_options *options, char *keyword)
 }
 
 /**
+ * po_contains_prefix - check for presence of an option matching a prefix
+ * @options: pointer to mount options
+ * @prefix: pointer to prefix to match against a keyword
+ * @keyword: pointer to a C string containing the option keyword if found
+ *
+ * On success, *keyword contains the pointer of the matching option's keyword.
+ */
+po_found_t po_contains_prefix(struct mount_options *options,
+								const char *prefix, char **keyword)
+{
+	struct mount_option *option;
+
+	if (options && prefix) {
+		for (option = options->head; option; option = option->next)
+			if (strncmp(option->keyword, prefix, strlen(prefix)) == 0) {
+				*keyword = option->keyword;
+				return PO_FOUND;
+			}
+	}
+
+	return PO_NOT_FOUND;
+}
+
+/**
  * po_get - return the value of the rightmost instance of an option
  * @options: pointer to mount options
  * @keyword: pointer to a C string containing option keyword for which to search
diff --git a/utils/mount/parse_opt.h b/utils/mount/parse_opt.h
index 5037207..0745e0f 100644
--- a/utils/mount/parse_opt.h
+++ b/utils/mount/parse_opt.h
@@ -45,6 +45,8 @@ po_return_t		po_join(struct mount_options *, char **);
 
 po_return_t		po_append(struct mount_options *, char *);
 po_found_t		po_contains(struct mount_options *, char *);
+po_found_t		po_contains_prefix(struct mount_options *options,
+						const char *prefix, char **keyword);
 char *			po_get(struct mount_options *, char *);
 po_found_t		po_get_numeric(struct mount_options *,
 					char *, long *);
-- 
1.7.1

[PATCH 4/6] mount.nfs: Add struct nfs_version and generalize version parsing

[Benjamin Coddington]

The nfs_version needs to carry major, minor, and basic mode information to
allow decisions to be made to override, discard, or negotiate various
versions.  Update nfs_nfs_version() to work against this struct and set the
various modes.  This change also makes nfs_nfs_version() parse properly
for future version number additions.

The general rules for version.v_mode are
 - not set             V_DEFAULT
 - single digit => 4   V_GENERAL
 - single digit < 4    V_SPECIFIC
 - decimal included    V_SPECIFIC
 - miss all others     V_PARSE_ERR

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 utils/mount/configfile.c |    2 +-
 utils/mount/network.c    |  122 ++++++++++++++++++++++-----------------------
 utils/mount/network.h    |   15 +++++-
 utils/mount/nfsumount.c  |    4 +-
 utils/mount/stropts.c    |   22 ++++----
 5 files changed, 88 insertions(+), 77 deletions(-)

diff --git a/utils/mount/configfile.c b/utils/mount/configfile.c
index 39d3741..a0072f1 100644
--- a/utils/mount/configfile.c
+++ b/utils/mount/configfile.c
@@ -258,7 +258,7 @@ check_vers(char *mopt, char *field)
 	return 0;
 }
 
-unsigned long config_default_vers;
+struct nfs_version config_default_vers;
 unsigned long config_default_proto;
 extern sa_family_t config_default_family;
 
diff --git a/utils/mount/network.c b/utils/mount/network.c
index 4f8c15c..b5ed850 100644
--- a/utils/mount/network.c
+++ b/utils/mount/network.c
@@ -92,9 +92,6 @@ static const char *nfs_version_opttbl[] = {
 	"v4",
 	"vers",
 	"nfsvers",
-	"v4.0",
-	"v4.1",
-	"v4.2",
 	NULL,
 };
 
@@ -1242,71 +1239,69 @@ nfs_nfs_program(struct mount_options *options, unsigned long *program)
  * or FALSE if the option was specified with an invalid value.
  */
 int
-nfs_nfs_version(struct mount_options *options, unsigned long *version)
+nfs_nfs_version(struct mount_options *options, struct nfs_version *version)
 {
-	long tmp;
+	char *version_key, *version_val, *cptr;
+	int i, found = 0;
 
-	switch (po_rightmost(options, nfs_version_opttbl)) {
-	case 0:	/* v2 */
-		*version = 2;
-		return 1;
-	case 1: /* v3 */
-		*version = 3;
-		return 1;
-	case 2: /* v4 */
-		*version = 4;
-		return 1;
-	case 3:	/* vers */
-		switch (po_get_numeric(options, "vers", &tmp)) {
-		case PO_FOUND:
-			if (tmp >= 2 && tmp <= 4) {
-				*version = tmp;
-				return 1;
-			}
-			nfs_error(_("%s: parsing error on 'vers=' option\n"),
-					progname);
-			return 0;
-		case PO_NOT_FOUND:
-			nfs_error(_("%s: parsing error on 'vers=' option\n"),
-					progname);
-			return 0;
-		case PO_BAD_VALUE:
-			nfs_error(_("%s: invalid value for 'vers=' option"),
-					progname);
-			return 0;
-		}
-	case 4: /* nfsvers */
-		switch (po_get_numeric(options, "nfsvers", &tmp)) {
-		case PO_FOUND:
-			if (tmp >= 2 && tmp <= 4) {
-				*version = tmp;
-				return 1;
-			}
-			nfs_error(_("%s: parsing error on 'nfsvers=' option\n"),
-					progname);
-			return 0;
-		case PO_NOT_FOUND:
-			nfs_error(_("%s: parsing error on 'nfsvers=' option\n"),
-					progname);
-			return 0;
-		case PO_BAD_VALUE:
-			nfs_error(_("%s: invalid value for 'nfsvers=' option"),
-					progname);
-			return 0;
+	version->v_mode = V_DEFAULT;
+
+	for (i = 0; nfs_version_opttbl[i]; i++) {
+		if (po_contains_prefix(options, nfs_version_opttbl[i],
+								&version_key) == PO_FOUND) {
+			found++;
+			break;
 		}
-	case 5: /* v4.0 */
-	case 6: /* v4.1 */
-	case 7: /* v4.2 */
-		*version = 4;
+	}
+
+	if (!found)
 		return 1;
+
+	if (i <= 2 ) {
+		/* v2, v3, v4 */
+		version_val = version_key + 1;
+		version->v_mode = V_SPECIFIC;
+	} else if (i > 2 ) {
+		/* vers=, nfsvers= */
+		version_val = po_get(options, version_key);
 	}
 
-	/*
-	 * NFS version wasn't specified.  The pmap version value
-	 * will be filled in later by an rpcbind query in this case.
-	 */
-	*version = 0;
+	if (!version_val)
+		goto ret_error;
+
+	if (!(version->major = strtol(version_val, &cptr, 10)))
+		goto ret_error;
+
+	if (version->major < 4)
+		version->v_mode = V_SPECIFIC;
+
+	if (*cptr == '.') {
+		version_val = ++cptr;
+		if (!(version->minor = strtol(version_val, &cptr, 10)) && cptr == version_val)
+			goto ret_error;
+		version->v_mode = V_SPECIFIC;
+	} else if (version->major > 3 && *cptr == '\0')
+		version->v_mode = V_GENERAL;
+
+	if (*cptr != '\0')
+		goto ret_error;
+
 	return 1;
+
+ret_error:
+	if (i <= 2 ) {
+		nfs_error(_("%s: parsing error on 'v' option"),
+			progname);
+	} else if (i == 3 ) {
+		nfs_error(_("%s: parsing error on 'vers=' option"),
+			progname);
+	} else if (i == 4) {
+		nfs_error(_("%s: parsing error on 'nfsvers=' option"),
+			progname);
+	}
+	version->v_mode = V_PARSE_ERR;
+	errno = EINVAL;
+	return 0;
 }
 
 /*
@@ -1625,10 +1620,13 @@ out_err:
 int nfs_options2pmap(struct mount_options *options,
 		     struct pmap *nfs_pmap, struct pmap *mnt_pmap)
 {
+	struct nfs_version version;
+
 	if (!nfs_nfs_program(options, &nfs_pmap->pm_prog))
 		return 0;
-	if (!nfs_nfs_version(options, &nfs_pmap->pm_vers))
+	if (!nfs_nfs_version(options, &version))
 		return 0;
+	nfs_pmap->pm_vers = version.major;
 	if (!nfs_nfs_protocol(options, &nfs_pmap->pm_prot))
 		return 0;
 	if (!nfs_nfs_port(options, &nfs_pmap->pm_port))
diff --git a/utils/mount/network.h b/utils/mount/network.h
index d7636d7..9cc5dec 100644
--- a/utils/mount/network.h
+++ b/utils/mount/network.h
@@ -57,9 +57,22 @@ int clnt_ping(struct sockaddr_in *, const unsigned long,
 
 struct mount_options;
 
+enum {
+	V_DEFAULT = 0,
+	V_GENERAL,
+	V_SPECIFIC,
+	V_PARSE_ERR,
+};
+
+struct nfs_version {
+	unsigned long major;
+	unsigned long minor;
+	int v_mode;
+};
+
 int nfs_nfs_proto_family(struct mount_options *options, sa_family_t *family);
 int nfs_mount_proto_family(struct mount_options *options, sa_family_t *family);
-int nfs_nfs_version(struct mount_options *options, unsigned long *version);
+int nfs_nfs_version(struct mount_options *options, struct nfs_version *version);
 int  nfs_nfs_protocol(struct mount_options *options, unsigned long *protocol);
 
 int nfs_options2pmap(struct mount_options *,
diff --git a/utils/mount/nfsumount.c b/utils/mount/nfsumount.c
index 3538d88..de284f2 100644
--- a/utils/mount/nfsumount.c
+++ b/utils/mount/nfsumount.c
@@ -179,10 +179,10 @@ static int nfs_umount_is_vers4(const struct mntentchn *mc)
 
 		options = po_split(pmc->m.mnt_opts);
 		if (options != NULL) {
-			unsigned long version;
+			struct nfs_version version;
 			int rc = nfs_nfs_version(options, &version);
 			po_destroy(options);
-			if (rc && version == 4)
+			if (rc && version.major == 4)
 				goto out_nfs4;
 		}
 
diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
index 2d72d5b..faa77cf 100644
--- a/utils/mount/stropts.c
+++ b/utils/mount/stropts.c
@@ -88,7 +88,7 @@ struct nfsmount_info {
 	struct mount_options	*options;	/* parsed mount options */
 	char			**extra_opts;	/* string for /etc/mtab */
 
-	unsigned long		version;	/* NFS version */
+	struct nfs_version	version;	/* NFS version */
 	int			flags,		/* MS_ flags */
 				fake,		/* actually do the mount? */
 				child;		/* forked bg child? */
@@ -99,13 +99,13 @@ static void nfs_default_version(struct nfsmount_info *mi);
 
 static void nfs_default_version(struct nfsmount_info *mi)
 {
-	extern unsigned long config_default_vers;
+	extern struct nfs_version config_default_vers;
 	/*
 	 * Use the default value set in the config file when
 	 * the version has not been explicitly set.
 	 */
-	if (mi->version == 0 && config_default_vers) {
-		if (config_default_vers < 4)
+	if (mi->version.major == 0 && config_default_vers.major) {
+		if (config_default_vers.major < 4)
 			mi->version = config_default_vers;
 	}
 }
@@ -300,7 +300,7 @@ static int nfs_set_version(struct nfsmount_info *mi)
 		return 0;
 
 	if (strncmp(mi->type, "nfs4", 4) == 0)
-		mi->version = 4;
+		mi->version.major = 4;
 
 	/*
 	 * Before 2.6.32, the kernel NFS client didn't
@@ -308,20 +308,20 @@ static int nfs_set_version(struct nfsmount_info *mi)
 	 * 4 cannot be included when autonegotiating
 	 * while running on those kernels.
 	 */
-	if (mi->version == 0 &&
+	if (mi->version.major == 0 &&
 	    linux_version_code() <= MAKE_VERSION(2, 6, 31))
-		mi->version = 3;
+		mi->version.major = 3;
 
 	/*
 	 * If we still don't know, check for version-specific
 	 * mount options.
 	 */
-	if (mi->version == 0) {
+	if (mi->version.major == 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;
+			mi->version.major = 3;
 	}
 
 	/*
@@ -691,7 +691,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
 		return result;
 	}
 
-	if (mi->version == 0) {
+	if (mi->version.major == 0) {
 		if (po_contains(options, "mounthost") ||
 			po_contains(options, "mountaddr") ||
 			po_contains(options, "mountvers") ||
@@ -839,7 +839,7 @@ static int nfs_try_mount(struct nfsmount_info *mi)
 {
 	int result = 0;
 
-	switch (mi->version) {
+	switch (mi->version.major) {
 	case 0:
 		result = nfs_autonegotiate(mi);
 		break;
-- 
1.7.1

[PATCH 5/6] nfsmount.conf: Always parse versions

[Benjamin Coddington]

In order to make decisions about which default version to use when only the
major version is specified, the nfsmount.conf Defaultvers options should
always be parsed, even when a version has already been specified.  Remove
the check and bypass for parsing the Defaultvers options from nfsmount.conf.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 utils/mount/configfile.c |   34 ----------------------------------
 1 files changed, 0 insertions(+), 34 deletions(-)

diff --git a/utils/mount/configfile.c b/utils/mount/configfile.c
index a0072f1..0a4cc04 100644
--- a/utils/mount/configfile.c
+++ b/utils/mount/configfile.c
@@ -228,35 +228,6 @@ void free_all(void)
 		free(entry);
 	}
 }
-static char *versions[] = {"v2", "v3", "v4", "vers", "nfsvers", NULL};
-static int 
-check_vers(char *mopt, char *field)
-{
-	int i, found=0;
-
-	/*
-	 * First check to see if the config setting is one 
-	 * of the many version settings
-	 */
-	for (i=0; versions[i]; i++) { 
-		if (strcasestr(field, versions[i]) != NULL) {
-			found++;
-			break;
-		}
-	}
-	if (!found)
-		return 0;
-	/*
-	 * It appears the version is being set, now see
-	 * if the version appears on the command 
-	 */
-	for (i=0; versions[i]; i++)  {
-		if (strcasestr(mopt, versions[i]) != NULL)
-			return 1;
-	}
-
-	return 0;
-}
 
 struct nfs_version config_default_vers;
 unsigned long config_default_proto;
@@ -331,11 +302,6 @@ conf_parse_mntopts(char *section, char *arg, char *opts)
 		snprintf(buf, BUFSIZ, "%s=", node->field);
 		if (opts && strcasestr(opts, buf) != NULL)
 			continue;
-		/* 
-		 * Protocol verions can be set in a number of ways
-		 */
-		if (opts && check_vers(opts, node->field))
-			continue;
 
 		if (lookup_entry(node->field) != NULL)
 			continue;
-- 
1.7.1

[PATCH 6/6] mount.nfs: configurable minor version defaults

[Benjamin Coddington]

Update nfsmount.conf to allow minor version specification, and rearrange
the autonegotiation logic to agreed upon best behavior.  Depending upon the
combination of values specified within nfsmount.conf and given to mount.nfs,
the retry behavior of mount.nfs varies according to the general rule of
defaulting to the most specific setting, with some exceptions.  A general
guide to the expected behavior follows:

┌────────────────┐
│ nfsmount.conf  ├──────────────┬───────────────────┐
│ Defaultvers=   │  arg option  │     attempts:     │
├────────────────┼──────────────┼───────────────────┤
│     4.2        │  not set     │ v4.2 v4.1 v4.0 v3 │
│     4.2        │   v4         │ v4.2 v4.1 v4.0    │
│     4.1        │  not set     │      v4.1 v4.0 v3 │
│     4.1        │   v4         │      v4.1 v4.0    │
│     4          │  not set     │           v4.0 v3 │
│     4          │   v4         │           v4.0    │
│     3          │  not set     │                v3 │
│    any set     │   v4.2       │ v4.2              │
│    any set     │   v4.1       │      v4.1         │
│    any set     │   v4         │           v4.0    │
│    any set     │   v3         │                v3 │
│    not set     │  not set     │ v4.2 v4.1 v4.0 v3 │
└────────────────┴──────────────┴───────────────────┘

If built with --enable-mountconfig=no, then the behavior is the same as if
nfsmount.conf did not set Defaultvers.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
---
 utils/mount/stropts.c |  138 +++++++++++++++++++++++++++++++++---------------
 1 files changed, 95 insertions(+), 43 deletions(-)

diff --git a/utils/mount/stropts.c b/utils/mount/stropts.c
index faa77cf..76ecb32 100644
--- a/utils/mount/stropts.c
+++ b/utils/mount/stropts.c
@@ -94,24 +94,44 @@ struct nfsmount_info {
 				child;		/* forked bg child? */
 };
 
-#ifdef MOUNT_CONFIG
-static void nfs_default_version(struct nfsmount_info *mi);
 
 static void nfs_default_version(struct nfsmount_info *mi)
 {
+#ifdef MOUNT_CONFIG
 	extern struct nfs_version config_default_vers;
 	/*
 	 * Use the default value set in the config file when
 	 * the version has not been explicitly set.
 	 */
-	if (mi->version.major == 0 && config_default_vers.major) {
-		if (config_default_vers.major < 4)
-			mi->version = config_default_vers;
+	if (config_default_vers.v_mode == V_PARSE_ERR) {
+		mi->version.v_mode = V_PARSE_ERR;
+		return;
 	}
-}
-#else
-inline void nfs_default_version(__attribute__ ((unused)) struct nfsmount_info *mi) {}
+
+	if (mi->version.v_mode == V_GENERAL &&
+		config_default_vers.v_mode == V_DEFAULT) {
+		mi->version.v_mode = V_SPECIFIC;
+		return;
+	}
+
+	if (mi->version.v_mode == V_DEFAULT &&
+		config_default_vers.v_mode != V_DEFAULT) {
+		mi->version.major = config_default_vers.major;
+		mi->version.minor = config_default_vers.minor;
+		return;
+	}
+
+	if (mi->version.v_mode == V_GENERAL &&
+		config_default_vers.v_mode != V_DEFAULT) {
+		if (mi->version.major == config_default_vers.major)
+			mi->version.minor = config_default_vers.minor;
+		return;
+	}
+
 #endif /* MOUNT_CONFIG */
+	mi->version.major = 4;
+	mi->version.minor = 2;
+}
 
 /*
  * Obtain a retry timeout value based on the value of the "retry=" option.
@@ -308,28 +328,44 @@ static int nfs_set_version(struct nfsmount_info *mi)
 	 * 4 cannot be included when autonegotiating
 	 * while running on those kernels.
 	 */
-	if (mi->version.major == 0 &&
-	    linux_version_code() <= MAKE_VERSION(2, 6, 31))
+	if (mi->version.v_mode == V_DEFAULT &&
+	    linux_version_code() <= MAKE_VERSION(2, 6, 31)) {
 		mi->version.major = 3;
+		mi->version.v_mode = V_SPECIFIC;
+	}
 
 	/*
 	 * If we still don't know, check for version-specific
 	 * mount options.
 	 */
-	if (mi->version.major == 0) {
+	if (mi->version.v_mode == V_DEFAULT) {
 		if (po_contains(mi->options, "mounthost") ||
 		    po_contains(mi->options, "mountaddr") ||
 		    po_contains(mi->options, "mountvers") ||
-		    po_contains(mi->options, "mountproto"))
+		    po_contains(mi->options, "mountproto")) {
 			mi->version.major = 3;
+			mi->version.v_mode = V_SPECIFIC;
+		}
 	}
 
 	/*
 	 * If enabled, see if the default version was
 	 * set in the config file
 	 */
-	nfs_default_version(mi);
-	
+	if (mi->version.v_mode != V_SPECIFIC) {
+		nfs_default_version(mi);
+		/*
+		 * If the version was not specifically set, it will
+		 * be set by autonegotiation later, so remove it now:
+		 */
+		po_remove_all(mi->options, "v4");
+		po_remove_all(mi->options, "vers");
+		po_remove_all(mi->options, "nfsvers");
+	}
+
+	if (mi->version.v_mode == V_PARSE_ERR)
+		return 0;
+
 	return 1;
 }
 
@@ -684,6 +720,7 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
 {
 	struct mount_options *options = po_dup(mi->options);
 	int result = 0;
+	char version_opt[16];
 	char *extra_opts = NULL;
 
 	if (!options) {
@@ -691,20 +728,24 @@ static int nfs_do_mount_v4(struct nfsmount_info *mi,
 		return result;
 	}
 
-	if (mi->version.major == 0) {
-		if (po_contains(options, "mounthost") ||
-			po_contains(options, "mountaddr") ||
-			po_contains(options, "mountvers") ||
-			po_contains(options, "mountproto")) {
-		/*
-		 * Since these mountd options are set assume version 3
-		 * is wanted so error out with EPROTONOSUPPORT so the
-		 * protocol negation starts with v3.
-		 */
-			errno = EPROTONOSUPPORT;
-			goto out_fail;
-		}
-		if (po_append(options, "vers=4") == PO_FAILED) {
+	if (po_contains(options, "mounthost") ||
+		po_contains(options, "mountaddr") ||
+		po_contains(options, "mountvers") ||
+		po_contains(options, "mountproto")) {
+	/*
+	 * Since these mountd options are set assume version 3
+	 * is wanted so error out with EPROTONOSUPPORT so the
+	 * protocol negation starts with v3.
+	 */
+		errno = EPROTONOSUPPORT;
+		goto out_fail;
+	}
+
+	if (mi->version.v_mode != V_SPECIFIC) {
+		snprintf(version_opt, sizeof(version_opt) - 1,
+			"vers=%lu.%lu", mi->version.major, mi->version.minor);
+
+		if (po_append(options, version_opt) == PO_FAILED) {
 			errno = EINVAL;
 			goto out_fail;
 		}
@@ -792,14 +833,25 @@ static int nfs_autonegotiate(struct nfsmount_info *mi)
 	int result;
 
 	result = nfs_try_mount_v4(mi);
+check_result:
 	if (result)
 		return result;
 
-check_errno:
 	switch (errno) {
 	case EPROTONOSUPPORT:
 		/* A clear indication that the server or our
-		 * client does not support NFS version 4. */
+		 * client does not support NFS version 4 and minor */
+		if (mi->version.v_mode == V_GENERAL &&
+			mi->version.minor == 0)
+				return result;
+		if (mi->version.v_mode != V_SPECIFIC) {
+			if (mi->version.minor > 0) {
+				mi->version.minor--;
+				result = nfs_try_mount_v4(mi);
+				goto check_result;
+			}
+		}
+
 		goto fall_back;
 	case ENOENT:
 		/* Legacy Linux servers don't export an NFS
@@ -818,7 +870,7 @@ check_errno:
 			/* v4 server seems to be registered now. */
 			result = nfs_try_mount_v4(mi);
 			if (result == 0 && errno != ECONNREFUSED)
-				goto check_errno;
+				goto check_result;
 		}
 		return result;
 	default:
@@ -840,18 +892,18 @@ static int nfs_try_mount(struct nfsmount_info *mi)
 	int result = 0;
 
 	switch (mi->version.major) {
-	case 0:
-		result = nfs_autonegotiate(mi);
-		break;
-	case 2:
-	case 3:
-		result = nfs_try_mount_v3v2(mi, FALSE);
-		break;
-	case 4:
-		result = nfs_try_mount_v4(mi);
-		break;
-	default:
-		errno = EIO;
+		case 2:
+		case 3:
+			result = nfs_try_mount_v3v2(mi, FALSE);
+			break;
+		case 4:
+			if (mi->version.v_mode != V_SPECIFIC)
+				result = nfs_autonegotiate(mi);
+			else
+				result = nfs_try_mount_v4(mi);
+			break;
+		default:
+			errno = EIO;
 	}
 
 	return result;
-- 
1.7.1

Re: [PATCH v2 0/6] mount.nfs default version

[Steve Dickson]

On 11/18/2014 09:06 AM, Benjamin Coddington wrote:
> Here's the work posted yesterday broken out a bit with an addition of
> enabling nfsmount.conf by default, and the change to autonegotiate starting
> with version 4.2 (instead of 4.0) when no version is specified in either
> config or mount option.
> 
> Benjamin Coddington (6):
>   mount.nfs: default enable mount config file (nfsmount.conf)
>   mount.nfs: fix a comment typo in parse options
>   mount.nfs: parse options - add helper po_contains_prefix
>   mount.nfs: Add struct nfs_version and generalize version parsing
>   nfsmount.conf: Always parse versions
>   mount.nfs: configurable minor version defaults
> 
>  configure.ac             |    8 +-
>  utils/mount/configfile.c |   36 +-----------
>  utils/mount/network.c    |  122 ++++++++++++++++++-------------------
>  utils/mount/network.h    |   15 ++++-
>  utils/mount/nfsumount.c  |    4 +-
>  utils/mount/parse_opt.c  |   26 ++++++++-
>  utils/mount/parse_opt.h  |    2 +
>  utils/mount/stropts.c    |  150 +++++++++++++++++++++++++++++++---------------
>  8 files changed, 209 insertions(+), 154 deletions(-)
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
Committed... But I did have to fix an issue with the first patch
See commit e1a49cf3... No biggie... 

steved.