NFSD: convert callback RPC program to per-net namespace

The callback channel's rpc_program, rpc_version, rpc_stat,
and per-procedure counts are declared as file-scope statics in
nfs4callback.c, shared across all network namespaces.
Forechannel RPC statistics are already maintained per-netns
(via nfsd_svcstats in struct nfsd_net); the backchannel
has no such separation. When backchannel statistics are
eventually surfaced to userspace, the global counters would
expose cross-namespace data.

Allocate per-netns copies of these structures through a new
opaque struct nfsd_net_cb, managed by nfsd_net_cb_init()
and nfsd_net_cb_shutdown(). The struct definition is private
to nfs4callback.c; struct nfsd_net holds only a pointer.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h
index 6ad3fe5d7e1248dfbc9f8b67a5ab957eb1978e54..27da1a3edacbf3f4598bbfad3f4579b8ee34ed49 100644 (file)
--- a/fs/nfsd/netns.h
+++ b/fs/nfsd/netns.h
@@ -25,6 +25,7 @@
 #define SESSION_HASH_SIZE      512
 
 struct cld_net;
+struct nfsd_net_cb;
 struct nfsd4_client_tracking_ops;
 
 enum {
@@ -228,6 +229,8 @@ struct nfsd_net {
        struct list_head        local_clients;
 #endif
        siphash_key_t           *fh_key;
+
+       struct nfsd_net_cb      *nfsd_cb;
 };
 
 /* Simple check to find out if a given net was properly initialized */

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 74effafdd0dc9cc8aba13c7cbf27efc89aafc1b7..50827405468d2fb3bd8365cb97eb6a0b49231ce0 100644 (file)
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -1032,39 +1032,14 @@ static const struct rpc_procinfo nfs4_cb_procedures[] = {
        PROC(CB_GETATTR,        COMPOUND,       cb_getattr,     cb_getattr),
 };
 
-static unsigned int nfs4_cb_counts[ARRAY_SIZE(nfs4_cb_procedures)];
-static const struct rpc_version nfs_cb_version4 = {
-/*
- * Note on the callback rpc program version number: despite language in rfc
- * 5661 section 18.36.3 requiring servers to use 4 in this field, the
- * official xdr descriptions for both 4.0 and 4.1 specify version 1, and
- * in practice that appears to be what implementations use.  The section
- * 18.36.3 language is expected to be fixed in an erratum.
- */
-       .number                 = 1,
-       .nrprocs                = ARRAY_SIZE(nfs4_cb_procedures),
-       .procs                  = nfs4_cb_procedures,
-       .counts                 = nfs4_cb_counts,
-};
-
-static const struct rpc_version *nfs_cb_version[2] = {
-       [1] = &nfs_cb_version4,
-};
-
-static const struct rpc_program cb_program;
-
-static struct rpc_stat cb_stats = {
-       .program                = &cb_program
-};
-
-#define NFS4_CALLBACK 0x40000000
-static const struct rpc_program cb_program = {
-       .name                   = "nfs4_cb",
-       .number                 = NFS4_CALLBACK,
-       .nrvers                 = ARRAY_SIZE(nfs_cb_version),
-       .version                = nfs_cb_version,
-       .stats                  = &cb_stats,
-       .pipe_dir_name          = "nfsd4_cb",
+#define NFS4_CB_PROGRAM        0x40000000
+#define NFS4_CB_VERSION        1
+
+struct nfsd_net_cb {
+       struct rpc_version      version4;
+       const struct rpc_version *versions[NFS4_CB_VERSION + 1];
+       struct rpc_program      program;
+       struct rpc_stat         stat;
 };
 
 static int max_cb_time(struct net *net)
@@ -1140,6 +1115,7 @@ static const struct cred *get_backchannel_cred(struct nfs4_client *clp, struct r
 
 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses)
 {
+       struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
        int maxtime = max_cb_time(clp->net);
        struct rpc_timeout      timeparms = {
                .to_initval     = maxtime,
@@ -1152,14 +1128,14 @@ static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *c
                .addrsize       = conn->cb_addrlen,
                .saddress       = (struct sockaddr *) &conn->cb_saddr,
                .timeout        = &timeparms,
-               .program        = &cb_program,
-               .version        = 1,
+               .version        = NFS4_CB_VERSION,
                .flags          = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
                .cred           = current_cred(),
        };
        struct rpc_clnt *client;
        const struct cred *cred;
 
+       args.program = &nn->nfsd_cb->program;
        if (clp->cl_minorversion == 0) {
                if (!clp->cl_cred.cr_principal &&
                    (clp->cl_cred.cr_flavor >= RPC_AUTH_GSS_KRB5)) {
@@ -1786,3 +1762,70 @@ bool nfsd4_run_cb(struct nfsd4_callback *cb)
                nfsd41_cb_inflight_end(clp);
        return queued;
 }
+
+/**
+ * nfsd_net_cb_shutdown - release per-netns callback RPC program resources
+ * @nn: NFS server network namespace
+ *
+ * Frees resources allocated by nfsd_net_cb_init().
+ */
+void nfsd_net_cb_shutdown(struct nfsd_net *nn)
+{
+       struct nfsd_net_cb *cb = nn->nfsd_cb;
+
+       if (cb) {
+               kfree(cb->version4.counts);
+               kfree(cb);
+               nn->nfsd_cb = NULL;
+       }
+}
+
+/**
+ * nfsd_net_cb_init - initialize per-netns callback RPC program
+ * @nn: NFS server network namespace
+ *
+ * Sets up the callback RPC program, version table, procedure
+ * counts, and statistics structure for @nn. Caller must release
+ * these resources using nfsd_net_cb_shutdown().
+ *
+ * Return: 0 on success, or -ENOMEM if allocation fails.
+ */
+int nfsd_net_cb_init(struct nfsd_net *nn)
+{
+       struct nfsd_net_cb *cb;
+
+       cb = kzalloc(sizeof(*cb), GFP_KERNEL);
+       if (!cb)
+               return -ENOMEM;
+
+       cb->version4.counts = kzalloc_objs(unsigned int,
+                       ARRAY_SIZE(nfs4_cb_procedures), GFP_KERNEL);
+       if (!cb->version4.counts) {
+               kfree(cb);
+               return -ENOMEM;
+       }
+       /*
+        * Note on the callback rpc program version number: despite language
+        * in rfc 5661 section 18.36.3 requiring servers to use 4 in this
+        * field, the official xdr descriptions for both 4.0 and 4.1 specify
+        * version 1, and in practice that appears to be what implementations
+        * use. The section 18.36.3 language is expected to be fixed in an
+        * erratum.
+        */
+       cb->version4.number = NFS4_CB_VERSION;
+       cb->version4.nrprocs = ARRAY_SIZE(nfs4_cb_procedures);
+       cb->version4.procs = nfs4_cb_procedures;
+       cb->versions[NFS4_CB_VERSION] = &cb->version4;
+
+       cb->program.name = "nfs4_cb";
+       cb->program.number = NFS4_CB_PROGRAM;
+       cb->program.nrvers = ARRAY_SIZE(cb->versions);
+       cb->program.version = &cb->versions[0];
+       cb->program.pipe_dir_name = "nfsd4_cb";
+       cb->program.stats = &cb->stat;
+       cb->stat.program = &cb->program;
+
+       nn->nfsd_cb = cb;
+
+       return 0;
+}

diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 20ec00f323b490e397c8d6907e7511bb24f94510..39e7012a60d8ebc4e86bcb2fed65051f2d3f357f 100644 (file)
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -2203,6 +2203,9 @@ static __net_init int nfsd_net_init(struct net *net)
        int retval;
        int i;
 
+       retval = nfsd_net_cb_init(nn);
+       if (retval)
+               return retval;
        retval = nfsd_export_init(net);
        if (retval)
                goto out_export_error;
@@ -2243,6 +2246,7 @@ out_repcache_error:
 out_idmap_error:
        nfsd_export_shutdown(net);
 out_export_error:
+       nfsd_net_cb_shutdown(nn);
        return retval;
 }
 
@@ -2273,6 +2277,7 @@ static __net_exit void nfsd_net_exit(struct net *net)
        struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
        kfree_sensitive(nn->fh_key);
+       nfsd_net_cb_shutdown(nn);
        nfsd_proc_stat_shutdown(net);
        percpu_counter_destroy_many(nn->counter, NFSD_STATS_COUNTERS_NUM);
        nfsd_idmap_shutdown(net);

diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 9b05462da4cc1353b09843eeddc972afbdaac574..953675eba5c36654937262ca8199d4b975723899 100644 (file)
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -862,6 +862,8 @@ struct nfsd_file *find_any_file(struct nfs4_file *f);
 #ifdef CONFIG_NFSD_V4
 void nfsd4_revoke_states(struct nfsd_net *nn, struct super_block *sb);
 void nfsd4_cancel_copy_by_sb(struct net *net, struct super_block *sb);
+int nfsd_net_cb_init(struct nfsd_net *nn);
+void nfsd_net_cb_shutdown(struct nfsd_net *nn);
 #else
 static inline void nfsd4_revoke_states(struct nfsd_net *nn, struct super_block *sb)
 {
@@ -869,6 +871,13 @@ static inline void nfsd4_revoke_states(struct nfsd_net *nn, struct super_block *
 static inline void nfsd4_cancel_copy_by_sb(struct net *net, struct super_block *sb)
 {
 }
+static inline int nfsd_net_cb_init(struct nfsd_net *nn)
+{
+       return 0;
+}
+static inline void nfsd_net_cb_shutdown(struct nfsd_net *nn)
+{
+}
 #endif
 
 /* grace period management */