nfsd: Allow containers to set supported nfs versions

Support use of the --nfs-version/--no-nfs-version arguments to rpc.nfsd
in containers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 168 insertions, 46 deletions

diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 378edcfe9701..520757774614 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -38,12 +38,18 @@ static int			nfsd_acl_rpcbind_set(struct net *,
 						     u32, int,
 						     unsigned short,
 						     unsigned short);
+static __be32			nfsd_acl_init_request(struct svc_rqst *,
+						const struct svc_program *,
+						struct svc_process_info *);
 #endif
 static int			nfsd_rpcbind_set(struct net *,
 						 const struct svc_program *,
 						 u32, int,
 						 unsigned short,
 						 unsigned short);
+static __be32			nfsd_init_request(struct svc_rqst *,
+						const struct svc_program *,
+						struct svc_process_info *);
 
 /*
  * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
@@ -98,7 +104,7 @@ static struct svc_program	nfsd_acl_program = {
 	.pg_class		= "nfsd",
 	.pg_stats		= &nfsd_acl_svcstats,
 	.pg_authenticate	= &svc_set_client,
-	.pg_init_request	= svc_generic_init_request,
+	.pg_init_request	= nfsd_acl_init_request,
 	.pg_rpcbind_set		= nfsd_acl_rpcbind_set,
 };
 
@@ -119,7 +125,6 @@ static const struct svc_version *nfsd_version[] = {
 
 #define NFSD_MINVERS    	2
 #define NFSD_NRVERS		ARRAY_SIZE(nfsd_version)
-static const struct svc_version *nfsd_versions[NFSD_NRVERS];
 
 struct svc_program		nfsd_program = {
 #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
@@ -127,78 +132,136 @@ struct svc_program		nfsd_program = {
 #endif
 	.pg_prog		= NFS_PROGRAM,		/* program number */
 	.pg_nvers		= NFSD_NRVERS,		/* nr of entries in nfsd_version */
-	.pg_vers		= nfsd_versions,	/* version table */
+	.pg_vers		= nfsd_version,		/* version table */
 	.pg_name		= "nfsd",		/* program name */
 	.pg_class		= "nfsd",		/* authentication class */
 	.pg_stats		= &nfsd_svcstats,	/* version table */
 	.pg_authenticate	= &svc_set_client,	/* export authentication */
-	.pg_init_request	= svc_generic_init_request,
+	.pg_init_request	= nfsd_init_request,
 	.pg_rpcbind_set		= nfsd_rpcbind_set,
 };
 
-static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = {
-	[0] = 1,
-	[1] = 1,
-	[2] = 1,
-};
+static bool
+nfsd_support_version(int vers)
+{
+	if (vers >= NFSD_MINVERS && vers < NFSD_NRVERS)
+		return nfsd_version[vers] != NULL;
+	return false;
+}
+
+static bool *
+nfsd_alloc_versions(void)
+{
+	bool *vers = kmalloc_array(NFSD_NRVERS, sizeof(bool), GFP_KERNEL);
+	unsigned i;
+
+	if (vers) {
+		/* All compiled versions are enabled by default */
+		for (i = 0; i < NFSD_NRVERS; i++)
+			vers[i] = nfsd_support_version(i);
+	}
+	return vers;
+}
+
+static bool *
+nfsd_alloc_minorversions(void)
+{
+	bool *vers = kmalloc_array(NFSD_SUPPORTED_MINOR_VERSION + 1,
+			sizeof(bool), GFP_KERNEL);
+	unsigned i;
 
-int nfsd_vers(int vers, enum vers_op change)
+	if (vers) {
+		/* All minor versions are enabled by default */
+		for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++)
+			vers[i] = nfsd_support_version(4);
+	}
+	return vers;
+}
+
+void
+nfsd_netns_free_versions(struct nfsd_net *nn)
+{
+	kfree(nn->nfsd_versions);
+	kfree(nn->nfsd4_minorversions);
+	nn->nfsd_versions = NULL;
+	nn->nfsd4_minorversions = NULL;
+}
+
+static void
+nfsd_netns_init_versions(struct nfsd_net *nn)
+{
+	if (!nn->nfsd_versions) {
+		nn->nfsd_versions = nfsd_alloc_versions();
+		nn->nfsd4_minorversions = nfsd_alloc_minorversions();
+		if (!nn->nfsd_versions || !nn->nfsd4_minorversions)
+			nfsd_netns_free_versions(nn);
+	}
+}
+
+int nfsd_vers(struct nfsd_net *nn, int vers, enum vers_op change)
 {
 	if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
 		return 0;
 	switch(change) {
 	case NFSD_SET:
-		nfsd_versions[vers] = nfsd_version[vers];
-#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
-		if (vers < NFSD_ACL_NRVERS)
-			nfsd_acl_versions[vers] = nfsd_acl_version[vers];
-#endif
+		if (nn->nfsd_versions)
+			nn->nfsd_versions[vers] = nfsd_support_version(vers);
 		break;
 	case NFSD_CLEAR:
-		nfsd_versions[vers] = NULL;
-#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
-		if (vers < NFSD_ACL_NRVERS)
-			nfsd_acl_versions[vers] = NULL;
-#endif
+		nfsd_netns_init_versions(nn);
+		if (nn->nfsd_versions)
+			nn->nfsd_versions[vers] = false;
 		break;
 	case NFSD_TEST:
-		return nfsd_versions[vers] != NULL;
+		if (nn->nfsd_versions)
+			return nn->nfsd_versions[vers];
+		/* Fallthrough */
 	case NFSD_AVAIL:
-		return nfsd_version[vers] != NULL;
+		return nfsd_support_version(vers);
 	}
 	return 0;
 }
 
 static void
-nfsd_adjust_nfsd_versions4(void)
+nfsd_adjust_nfsd_versions4(struct nfsd_net *nn)
 {
 	unsigned i;
 
 	for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
-		if (nfsd_supported_minorversions[i])
+		if (nn->nfsd4_minorversions[i])
 			return;
 	}
-	nfsd_vers(4, NFSD_CLEAR);
+	nfsd_vers(nn, 4, NFSD_CLEAR);
 }
 
-int nfsd_minorversion(u32 minorversion, enum vers_op change)
+int nfsd_minorversion(struct nfsd_net *nn, u32 minorversion, enum vers_op change)
 {
 	if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
 	    change != NFSD_AVAIL)
 		return -1;
+
 	switch(change) {
 	case NFSD_SET:
-		nfsd_supported_minorversions[minorversion] = true;
-		nfsd_vers(4, NFSD_SET);
+		if (nn->nfsd4_minorversions) {
+			nfsd_vers(nn, 4, NFSD_SET);
+			nn->nfsd4_minorversions[minorversion] =
+				nfsd_vers(nn, 4, NFSD_TEST);
+		}
 		break;
 	case NFSD_CLEAR:
-		nfsd_supported_minorversions[minorversion] = false;
-		nfsd_adjust_nfsd_versions4();
+		nfsd_netns_init_versions(nn);
+		if (nn->nfsd4_minorversions) {
+			nn->nfsd4_minorversions[minorversion] = false;
+			nfsd_adjust_nfsd_versions4(nn);
+		}
 		break;
 	case NFSD_TEST:
-		return nfsd_supported_minorversions[minorversion];
+		if (nn->nfsd4_minorversions)
+			return nn->nfsd4_minorversions[minorversion];
+		return nfsd_vers(nn, 4, NFSD_TEST);
 	case NFSD_AVAIL:
-		return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
+		return minorversion <= NFSD_SUPPORTED_MINOR_VERSION &&
+			nfsd_vers(nn, 4, NFSD_AVAIL);
 	}
 	return 0;
 }
@@ -280,13 +343,9 @@ static void nfsd_shutdown_generic(void)
 	nfsd_racache_shutdown();
 }
 
-static bool nfsd_needs_lockd(void)
+static bool nfsd_needs_lockd(struct nfsd_net *nn)
 {
-#if defined(CONFIG_NFSD_V3)
-	return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
-#else
-	return (nfsd_versions[2] != NULL);
-#endif
+	return nfsd_vers(nn, 2, NFSD_TEST) || nfsd_vers(nn, 3, NFSD_TEST);
 }
 
 static int nfsd_startup_net(int nrservs, struct net *net)
@@ -304,7 +363,7 @@ static int nfsd_startup_net(int nrservs, struct net *net)
 	if (ret)
 		goto out_socks;
 
-	if (nfsd_needs_lockd() && !nn->lockd_up) {
+	if (nfsd_needs_lockd(nn) && !nn->lockd_up) {
 		ret = lockd_up(net);
 		if (ret)
 			goto out_socks;
@@ -437,20 +496,20 @@ static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
 	nfsd_export_flush(net);
 }
 
-void nfsd_reset_versions(void)
+void nfsd_reset_versions(struct nfsd_net *nn)
 {
 	int i;
 
 	for (i = 0; i < NFSD_NRVERS; i++)
-		if (nfsd_vers(i, NFSD_TEST))
+		if (nfsd_vers(nn, i, NFSD_TEST))
 			return;
 
 	for (i = 0; i < NFSD_NRVERS; i++)
 		if (i != 4)
-			nfsd_vers(i, NFSD_SET);
+			nfsd_vers(nn, i, NFSD_SET);
 		else {
 			int minor = 0;
-			while (nfsd_minorversion(minor, NFSD_SET) >= 0)
+			while (nfsd_minorversion(nn, minor, NFSD_SET) >= 0)
 				minor++;
 		}
 }
@@ -518,7 +577,7 @@ int nfsd_create_serv(struct net *net)
 	}
 	if (nfsd_max_blksize == 0)
 		nfsd_max_blksize = nfsd_get_default_max_blksize();
-	nfsd_reset_versions();
+	nfsd_reset_versions(nn);
 	nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
 						&nfsd_thread_sv_ops);
 	if (nn->nfsd_serv == NULL)
@@ -697,11 +756,44 @@ nfsd_acl_rpcbind_set(struct net *net, const struct svc_program *progp,
 		     unsigned short port)
 {
 	if (!nfsd_support_acl_version(version) ||
-	    !nfsd_vers(version, NFSD_TEST))
+	    !nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
 		return 0;
 	return svc_generic_rpcbind_set(net, progp, version, family,
 			proto, port);
 }
+
+static __be32
+nfsd_acl_init_request(struct svc_rqst *rqstp,
+		      const struct svc_program *progp,
+		      struct svc_process_info *ret)
+{
+	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+	int i;
+
+	if (likely(nfsd_support_acl_version(rqstp->rq_vers) &&
+	    nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
+		return svc_generic_init_request(rqstp, progp, ret);
+
+	ret->mismatch.lovers = NFSD_ACL_NRVERS;
+	for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) {
+		if (nfsd_support_acl_version(rqstp->rq_vers) &&
+		    nfsd_vers(nn, i, NFSD_TEST)) {
+			ret->mismatch.lovers = i;
+			break;
+		}
+	}
+	if (ret->mismatch.lovers == NFSD_ACL_NRVERS)
+		return rpc_prog_unavail;
+	ret->mismatch.hivers = NFSD_ACL_MINVERS;
+	for (i = NFSD_ACL_NRVERS - 1; i >= NFSD_ACL_MINVERS; i--) {
+		if (nfsd_support_acl_version(rqstp->rq_vers) &&
+		    nfsd_vers(nn, i, NFSD_TEST)) {
+			ret->mismatch.hivers = i;
+			break;
+		}
+	}
+	return rpc_prog_mismatch;
+}
 #endif
 
 static int
@@ -709,12 +801,42 @@ nfsd_rpcbind_set(struct net *net, const struct svc_program *progp,
 		 u32 version, int family, unsigned short proto,
 		 unsigned short port)
 {
-	if (!nfsd_vers(version, NFSD_TEST))
+	if (!nfsd_vers(net_generic(net, nfsd_net_id), version, NFSD_TEST))
 		return 0;
 	return svc_generic_rpcbind_set(net, progp, version, family,
 			proto, port);
 }
 
+static __be32
+nfsd_init_request(struct svc_rqst *rqstp,
+		  const struct svc_program *progp,
+		  struct svc_process_info *ret)
+{
+	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+	int i;
+
+	if (likely(nfsd_vers(nn, rqstp->rq_vers, NFSD_TEST)))
+		return svc_generic_init_request(rqstp, progp, ret);
+
+	ret->mismatch.lovers = NFSD_NRVERS;
+	for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) {
+		if (nfsd_vers(nn, i, NFSD_TEST)) {
+			ret->mismatch.lovers = i;
+			break;
+		}
+	}
+	if (ret->mismatch.lovers == NFSD_NRVERS)
+		return rpc_prog_unavail;
+	ret->mismatch.hivers = NFSD_MINVERS;
+	for (i = NFSD_NRVERS - 1; i >= NFSD_MINVERS; i--) {
+		if (nfsd_vers(nn, i, NFSD_TEST)) {
+			ret->mismatch.hivers = i;
+			break;
+		}
+	}
+	return rpc_prog_mismatch;
+}
+
 /*
  * This is the NFS server kernel thread
  */