Commit cfe1f877 authored by Benjamin Coddington's avatar Benjamin Coddington Committed by Trond Myklebust
Browse files

NFS: Extend rdirplus mount option with "force|none" 



There are certain users that wish to force the NFS client to choose
READDIRPLUS over READDIR for a particular mount.  Update the "rdirplus" mount
option to optionally accept values.  For "rdirplus=force", the NFS client
will always attempt to use READDDIRPLUS.  The setting of "rdirplus=none" is
aliased to the existing "nordirplus".

Signed-off-by: default avatarBenjamin Coddington <bcodding@redhat.com>
Link: https://lore.kernel.org/r/c4cf0de4c8be0930b91bc74bee310d289781cd3b.1741885071.git.bcodding@redhat.com


Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent 2d6a194f

fs/nfs/dir.c

+2 −0
Original line number Diff line number Diff line
@@ -666,6 +666,8 @@ static bool nfs_use_readdirplus(struct inode *dir, struct dir_context *ctx, 
{

	if (!nfs_server_capable(dir, NFS_CAP_READDIRPLUS))

		return false;

	if (NFS_SERVER(dir)->flags & NFS_MOUNT_FORCE_RDIRPLUS)

		return true;

	if (ctx->pos == 0 ||

	    cache_hits + cache_misses > NFS_READDIR_CACHE_USAGE_THRESHOLD)

		return true;

fs/nfs/fs_context.c

+28 −4
Original line number Diff line number Diff line
@@ -72,6 +72,8 @@ enum nfs_param { 
	Opt_posix,

	Opt_proto,

	Opt_rdirplus,

	Opt_rdirplus_none,

	Opt_rdirplus_force,

	Opt_rdma,

	Opt_resvport,

	Opt_retrans,
@@ -174,7 +176,8 @@ static const struct fs_parameter_spec nfs_fs_parameters[] = { 
	fsparam_u32   ("port",		Opt_port),

	fsparam_flag_no("posix",	Opt_posix),

	fsparam_string("proto",		Opt_proto),

	fsparam_flag_no("rdirplus",	Opt_rdirplus),

	fsparam_flag_no("rdirplus", Opt_rdirplus), // rdirplus|nordirplus

	fsparam_string("rdirplus",  Opt_rdirplus), // rdirplus=...

	fsparam_flag  ("rdma",		Opt_rdma),

	fsparam_flag_no("resvport",	Opt_resvport),

	fsparam_u32   ("retrans",	Opt_retrans),
@@ -288,6 +291,12 @@ static const struct constant_table nfs_xprtsec_policies[] = { 
	{}

};



static const struct constant_table nfs_rdirplus_tokens[] = {

	{ "none",	Opt_rdirplus_none },

	{ "force",	Opt_rdirplus_force },

	{}

};



/*

 * Sanity-check a server address provided by the mount command.

 *
@@ -636,10 +645,25 @@ static int nfs_fs_context_parse_param(struct fs_context *fc, 
			ctx->flags &= ~NFS_MOUNT_NOACL;

		break;

	case Opt_rdirplus:

		if (result.negated)

		if (result.negated) {

			ctx->flags &= ~NFS_MOUNT_FORCE_RDIRPLUS;

			ctx->flags |= NFS_MOUNT_NORDIRPLUS;

		else

		} else if (!param->string) {

			ctx->flags &= ~(NFS_MOUNT_NORDIRPLUS | NFS_MOUNT_FORCE_RDIRPLUS);

		} else {

			switch (lookup_constant(nfs_rdirplus_tokens, param->string, -1)) {

			case Opt_rdirplus_none:

				ctx->flags &= ~NFS_MOUNT_FORCE_RDIRPLUS;

				ctx->flags |= NFS_MOUNT_NORDIRPLUS;

				break;

			case Opt_rdirplus_force:

				ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;

				ctx->flags |= NFS_MOUNT_FORCE_RDIRPLUS;

				break;

			default:

				goto out_invalid_value;

			}

		}

		break;

	case Opt_sharecache:

		if (result.negated)

fs/nfs/super.c

+1 −0
Original line number Diff line number Diff line
@@ -454,6 +454,7 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 
		{ NFS_MOUNT_NONLM, ",nolock", "" },

		{ NFS_MOUNT_NOACL, ",noacl", "" },

		{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },

		{ NFS_MOUNT_FORCE_RDIRPLUS, ",rdirplus=force", "" },

		{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },

		{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },

		{ 0, NULL, NULL }

include/linux/nfs_fs_sb.h

+1 −0
Original line number Diff line number Diff line
@@ -167,6 +167,7 @@ struct nfs_server { 
#define NFS_MOUNT_TRUNK_DISCOVERY	0x04000000

#define NFS_MOUNT_SHUTDOWN			0x08000000

#define NFS_MOUNT_NO_ALIGNWRITE		0x10000000

#define NFS_MOUNT_FORCE_RDIRPLUS	0x20000000



	unsigned int		fattr_valid;	/* Valid attributes */

	unsigned int		caps;		/* server capabilities */