Re: [nfs-utils PATCH] nfsdctl: tweak the version subcommand behavior

[Steve Dickson <steved@redhat.com>]

On 1/8/25 5:54 PM, Scott Mayhew wrote:
> The section for the 'nfsdctl version' subcommand on the man page states
> that the minorversion is optional, and if omitted it will cause all
> minorversions to be enabled/disabled, but it currently doesn't work that
> way.
> 
> Make it work that way, with one exception.  If v4.0 is disabled, then
> 'nfsdctl version +4' will not re-enable it; instead it must be
> explicitly re-enabled via 'nfsdctl version +4.0'.  This mirrors the way
> /proc/fs/nfsd/versions works.
> 
> Link: https://issues.redhat.com/browse/RHEL-72477
> Signed-off-by: Scott Mayhew <smayhew@redhat.com>
> ---
>   utils/nfsdctl/nfsdctl.8    |  9 ++++--
>   utils/nfsdctl/nfsdctl.adoc |  5 +++-
>   utils/nfsdctl/nfsdctl.c    | 58 +++++++++++++++++++++++++++++++++++---
>   3 files changed, 64 insertions(+), 8 deletions(-)
> 
> diff --git a/utils/nfsdctl/nfsdctl.8 b/utils/nfsdctl/nfsdctl.8
> index b08fe803..835d60b4 100644
> --- a/utils/nfsdctl/nfsdctl.8
> +++ b/utils/nfsdctl/nfsdctl.8
> @@ -2,12 +2,12 @@
>   .\"     Title: nfsdctl
>   .\"    Author: Jeff Layton
>   .\" Generator: Asciidoctor 2.0.20
> -.\"      Date: 2024-12-30
> +.\"      Date: 2025-01-08
>   .\"    Manual: \ \&
>   .\"    Source: \ \&
>   .\"  Language: English
>   .\"
> -.TH "NFSDCTL" "8" "2024-12-30" "\ \&" "\ \&"
> +.TH "NFSDCTL" "8" "2025-01-08" "\ \&" "\ \&"
>   .ie \n(.g .ds Aq \(aq
>   .el       .ds Aq '
>   .ss \n[.ss] 0
> @@ -172,7 +172,10 @@ MINOR: the minor version integer value
>   .nf
>   .fam C
>   The minorversion field is optional. If not given, it will disable or enable
> -all minorversions for that major version.
> +all minorversions for that major version.  Note however that if NFSv4.0 was
> +previously disabled, it can only be re\-enabled by explicitly specifying the
> +minorversion (this mirrors the behavior of the /proc/fs/nfsd/versions
> +interface).
>   .fam
>   .fi
>   .if n .RE
> diff --git a/utils/nfsdctl/nfsdctl.adoc b/utils/nfsdctl/nfsdctl.adoc
> index c5921458..20e9bf8e 100644
> --- a/utils/nfsdctl/nfsdctl.adoc
> +++ b/utils/nfsdctl/nfsdctl.adoc
> @@ -91,7 +91,10 @@ Each subcommand can also accept its own set of options and arguments. The
>       MINOR: the minor version integer value
>   
>     The minorversion field is optional. If not given, it will disable or enable
> -  all minorversions for that major version.
> +  all minorversions for that major version.  Note however that if NFSv4.0 was
> +  previously disabled, it can only be re-enabled by explicitly specifying the
> +  minorversion (this mirrors the behavior of the /proc/fs/nfsd/versions
> +  interface).
>   
>     Note that versions can only be set when there are no nfsd threads running.
>   
> diff --git a/utils/nfsdctl/nfsdctl.c b/utils/nfsdctl/nfsdctl.c
> index 722bf4a0..d86ff80e 100644
> --- a/utils/nfsdctl/nfsdctl.c
> +++ b/utils/nfsdctl/nfsdctl.c
> @@ -761,6 +761,32 @@ static int update_nfsd_version(int major, int minor, bool enabled)
>   	return -EINVAL;
>   }
>   
> +static bool v40_is_disabled(void)
> +{
> +	int i;
> +
> +	for (i = 0; i < MAX_NFS_VERSIONS; ++i) {
> +		if (nfsd_versions[i].major == 0)
> +			break;
> +		if (nfsd_versions[i].major == 4 && nfsd_versions[i].minor == 0)
> +			return !nfsd_versions[i].enabled;
> +	}
> +	return false;
> +}
> +
> +static int get_max_minorversion(void)
> +{
> +	int i, max = 0;
> +
> +	for (i = 0; i < MAX_NFS_VERSIONS; ++i) {
> +		if (nfsd_versions[i].major == 0)
> +			break;
> +		if (nfsd_versions[i].major == 4 && nfsd_versions[i].minor > max)
> +			max = nfsd_versions[i].minor;
> +	}
> +	return max;
> +}
> +
>   static void version_usage(void)
>   {
>   	printf("Usage: %s version { {+,-}major.minor } ...\n", taskname);
> @@ -778,7 +804,8 @@ static void version_usage(void)
>   
>   static int version_func(struct nl_sock *sock, int argc, char ** argv)
>   {
> -	int ret, i;
> +	int ret, i, j, max_minor;
> +	bool v40_disabled;
>   
>   	/* help is only valid as first argument after command */
>   	if (argc > 1 &&
> @@ -792,6 +819,9 @@ static int version_func(struct nl_sock *sock, int argc, char ** argv)
>   		return ret;
>   
>   	if (argc > 1) {
> +		v40_disabled = v40_is_disabled();
> +		max_minor = get_max_minorversion();
> +
>   		for (i = 1; i < argc; ++i) {
>   			int ret, major, minor = 0;
>   			char sign = '\0', *str = argv[i];
> @@ -815,9 +845,29 @@ static int version_func(struct nl_sock *sock, int argc, char ** argv)
>   				return -EINVAL;
>   			}
>   
> -			ret = update_nfsd_version(major, minor, enabled);
> -			if (ret)
> -				return ret;
> +			/*
> +			 * The minorversion field is optional. If omitted, it should
> +			 * cause all the minor versions for that major version to be
> +			 * enabled/disabled.
> +			 *
> +			 * HOWEVER, we do not enable v4.0 in this manner if it was
> +			 * previously disabled - it has to be explicitly enabled
> +			 * instead.  This is to retain the behavior of the old
> +			 * /proc/fs/nfsd/versions interface.
> +			 */
> +			if (major == 4 && ret == 2) {
> +				for (j = 0; j <= max_minor; ++j) {
> +					if (j == 0 && enabled && v40_disabled)
> +						continue;
> +					ret = update_nfsd_version(major, j, enabled);
> +					if (ret)
> +						return ret;
> +				}
> +			} else {
> +				ret = update_nfsd_version(major, minor, enabled);
> +				if (ret)
> +					return ret;
> +			}
>   		}
>   		return set_nfsd_versions(sock);
>   	}
So nfsdctl version -4 turns of all v4 versions
and nfsdctl version +4 only turns on +4.1 +4.2.
nfsdctl version +4.0 is needed to turn on 4.0
leaving the rest of the minor versions on

Is this intended?

steved.