svcrdma: Create a kmem cache for the WR contexts

Create a kmem cache to hold WR contexts. Next we will convert
the WR context get and put services to use this kmem cache.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>

net/sunrpc/xprtrdma/svc_rdma.c

@@ -69,8 +69,9 @@ atomic_t rdma_stat_rq_prod;
 atomic_t rdma_stat_sq_poll;
 atomic_t rdma_stat_sq_prod;
 
-/* Temporary NFS request map cache */
+/* Temporary NFS request map and context caches */
 struct kmem_cache *svc_rdma_map_cachep;
+struct kmem_cache *svc_rdma_ctxt_cachep;
 
 /*
  * This function implements reading and resetting an atomic_t stat
@@ -246,6 +247,7 @@ void svc_rdma_cleanup(void)
 	}
 	svc_unreg_xprt_class(&svc_rdma_class);
 	kmem_cache_destroy(svc_rdma_map_cachep);
+	kmem_cache_destroy(svc_rdma_ctxt_cachep);
 }
 
 int svc_rdma_init(void)
@@ -268,14 +270,27 @@ int svc_rdma_init(void)
 						NULL);
 	if (!svc_rdma_map_cachep) {
 		printk(KERN_INFO "Could not allocate map cache.\n");
-		goto err;
+		goto err0;
+	}
+
+	/* Create the temporary context cache */
+	svc_rdma_ctxt_cachep =
+		kmem_cache_create("svc_rdma_ctxt_cache",
+				  sizeof(struct svc_rdma_op_ctxt),
+				  0,
+				  SLAB_HWCACHE_ALIGN,
+				  NULL);
+	if (!svc_rdma_ctxt_cachep) {
+		printk(KERN_INFO "Could not allocate WR ctxt cache.\n");
+		goto err1;
 	}
 
 	/* Register RDMA with the SVC transport switch */
 	svc_reg_xprt_class(&svc_rdma_class);
 	return 0;
-
- err:
+ err1:
+	kmem_cache_destroy(svc_rdma_map_cachep);
+ err0:
 	unregister_sysctl_table(svcrdma_table_header);
 	return -ENOMEM;
 }