SUNRPC: Make rpc_clnt store the multipath iterators

This is a pre-patch for the RPC multipath code. It sets up the storage in
struct rpc_clnt for the multipath code.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 0c5c2cb..1713e41 100644 (file)
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -25,6 +25,7 @@
 #include <asm/signal.h>
 #include <linux/path.h>
 #include <net/ipv6.h>
+#include <linux/sunrpc/xprtmultipath.h>
 
 struct rpc_inode;
 
@@ -67,6 +68,7 @@ struct rpc_clnt {
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
        struct dentry           *cl_debugfs;    /* debugfs directory */
 #endif
+       struct rpc_xprt_iter    cl_xpi;
 };
 
 /*

diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 799e65b..3ce391c 100644 (file)
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -1181,12 +1181,12 @@ static struct rpc_auth *
 gss_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
 {
        struct gss_auth *gss_auth;
-       struct rpc_xprt *xprt = rcu_access_pointer(clnt->cl_xprt);
+       struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch);
 
        while (clnt != clnt->cl_parent) {
                struct rpc_clnt *parent = clnt->cl_parent;
                /* Find the original parent for this transport */
-               if (rcu_access_pointer(parent->cl_xprt) != xprt)
+               if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps)
                        break;
                clnt = parent;
        }

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 2b4ad7a..625fb8a 100644 (file)
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -354,6 +354,7 @@ static void rpc_free_clid(struct rpc_clnt *clnt)
 }
 
 static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
+               struct rpc_xprt_switch *xps,
                struct rpc_xprt *xprt,
                struct rpc_clnt *parent)
 {
@@ -411,6 +412,8 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args,
        }
 
        rpc_clnt_set_transport(clnt, xprt, timeout);
+       xprt_iter_init(&clnt->cl_xpi, xps);
+       xprt_switch_put(xps);
 
        clnt->cl_rtt = &clnt->cl_rtt_default;
        rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
@@ -438,6 +441,7 @@ out_no_clid:
 out_err:
        rpciod_down();
 out_no_rpciod:
+       xprt_switch_put(xps);
        xprt_put(xprt);
        return ERR_PTR(err);
 }
@@ -446,8 +450,13 @@ struct rpc_clnt *rpc_create_xprt(struct rpc_create_args *args,
                                        struct rpc_xprt *xprt)
 {
        struct rpc_clnt *clnt = NULL;
+       struct rpc_xprt_switch *xps;
 
-       clnt = rpc_new_client(args, xprt, NULL);
+       xps = xprt_switch_alloc(xprt, GFP_KERNEL);
+       if (xps == NULL)
+               return ERR_PTR(-ENOMEM);
+
+       clnt = rpc_new_client(args, xps, xprt, NULL);
        if (IS_ERR(clnt))
                return clnt;
 
@@ -564,6 +573,7 @@ EXPORT_SYMBOL_GPL(rpc_create);
 static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
                                           struct rpc_clnt *clnt)
 {
+       struct rpc_xprt_switch *xps;
        struct rpc_xprt *xprt;
        struct rpc_clnt *new;
        int err;
@@ -571,13 +581,17 @@ static struct rpc_clnt *__rpc_clone_client(struct rpc_create_args *args,
        err = -ENOMEM;
        rcu_read_lock();
        xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
+       xps = xprt_switch_get(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
        rcu_read_unlock();
-       if (xprt == NULL)
+       if (xprt == NULL || xps == NULL) {
+               xprt_put(xprt);
+               xprt_switch_put(xps);
                goto out_err;
+       }
        args->servername = xprt->servername;
        args->nodename = clnt->cl_nodename;
 
-       new = rpc_new_client(args, xprt, clnt);
+       new = rpc_new_client(args, xps, xprt, clnt);
        if (IS_ERR(new)) {
                err = PTR_ERR(new);
                goto out_err;
@@ -657,6 +671,7 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
 {
        const struct rpc_timeout *old_timeo;
        rpc_authflavor_t pseudoflavor;
+       struct rpc_xprt_switch *xps, *oldxps;
        struct rpc_xprt *xprt, *old;
        struct rpc_clnt *parent;
        int err;
@@ -668,10 +683,17 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
                return PTR_ERR(xprt);
        }
 
+       xps = xprt_switch_alloc(xprt, GFP_KERNEL);
+       if (xps == NULL) {
+               xprt_put(xprt);
+               return -ENOMEM;
+       }
+
        pseudoflavor = clnt->cl_auth->au_flavor;
 
        old_timeo = clnt->cl_timeout;
        old = rpc_clnt_set_transport(clnt, xprt, timeout);
+       oldxps = xprt_iter_xchg_switch(&clnt->cl_xpi, xps);
 
        rpc_unregister_client(clnt);
        __rpc_clnt_remove_pipedir(clnt);
@@ -697,14 +719,17 @@ int rpc_switch_client_transport(struct rpc_clnt *clnt,
        synchronize_rcu();
        if (parent != clnt)
                rpc_release_client(parent);
+       xprt_switch_put(oldxps);
        xprt_put(old);
        dprintk("RPC:       replaced xprt for clnt %p\n", clnt);
        return 0;
 
 out_revert:
+       xps = xprt_iter_xchg_switch(&clnt->cl_xpi, oldxps);
        rpc_clnt_set_transport(clnt, old, old_timeo);
        clnt->cl_parent = parent;
        rpc_client_register(clnt, pseudoflavor, NULL);
+       xprt_switch_put(xps);
        xprt_put(xprt);
        dprintk("RPC:       failed to switch xprt for clnt %p\n", clnt);
        return err;
@@ -783,6 +808,7 @@ rpc_free_client(struct rpc_clnt *clnt)
        rpc_free_iostats(clnt->cl_metrics);
        clnt->cl_metrics = NULL;
        xprt_put(rcu_dereference_raw(clnt->cl_xprt));
+       xprt_iter_destroy(&clnt->cl_xpi);
        rpciod_down();
        rpc_free_clid(clnt);
        kfree(clnt);

diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
index cf5770d..44f025c 100644 (file)
--- a/net/sunrpc/rpcb_clnt.c
+++ b/net/sunrpc/rpcb_clnt.c
@@ -648,10 +648,10 @@ static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbi
 static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
 {
        struct rpc_clnt *parent = clnt->cl_parent;
-       struct rpc_xprt *xprt = rcu_dereference(clnt->cl_xprt);
+       struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch);
 
        while (parent != clnt) {
-               if (rcu_dereference(parent->cl_xprt) != xprt)
+               if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps)
                        break;
                if (clnt->cl_autobind)
                        break;