[v3,RFC] rdma/cm: support option to allow manually setting IB path

Commit Message

Hefty, Sean Oct. 22, 2009, 8:26 p.m. UTC

None

Patch

diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c
index 1865049..2e73dcc 100644
--- a/drivers/infiniband/core/sa_query.c
+++ b/drivers/infiniband/core/sa_query.c
@@ -604,6 +604,12 @@  retry:
 	return ret ? ret : id;
 }
 
+void ib_sa_unpack_path(void *attribute, struct ib_sa_path_rec *rec)
+{
+	ib_unpack(path_rec_table, ARRAY_SIZE(path_rec_table), attribute, rec);
+}
+EXPORT_SYMBOL(ib_sa_unpack_path);
+
 static void ib_sa_path_rec_callback(struct ib_sa_query *sa_query,
 				    int status,
 				    struct ib_sa_mad *mad)
diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c
index 4346a24..23d9939 100644
--- a/drivers/infiniband/core/ucma.c
+++ b/drivers/infiniband/core/ucma.c
@@ -42,6 +42,7 @@ 
 #include <rdma/rdma_user_cm.h>
 #include <rdma/ib_marshall.h>
 #include <rdma/rdma_cm.h>
+#include <rdma/rdma_cm_ib.h>
 
 MODULE_AUTHOR("Sean Hefty");
 MODULE_DESCRIPTION("RDMA Userspace Connection Manager Access");
@@ -811,6 +812,51 @@  static int ucma_set_option_id(struct ucma_context *ctx, int optname,
 	return ret;
 }
 
+static int ucma_set_ib_path(struct ucma_context *ctx,
+			    struct ib_path_rec_data *path_data, size_t optlen)
+{
+	struct ib_sa_path_rec sa_path;
+	struct rdma_cm_event event;
+	int ret;
+
+	if (optlen % sizeof(*path_data))
+		return -EINVAL;
+
+	for (; optlen; optlen -= sizeof(*path_data), path_data++) {
+		if (path_data->flags == (IB_PATH_GMP | IB_PATH_PRIMARY |
+					 IB_PATH_BIDIRECTIONAL))
+			break;
+	}
+
+	if (!optlen)
+		return -EINVAL;
+
+	ib_sa_unpack_path(path_data->path_rec, &sa_path);
+	ret = rdma_set_ib_paths(ctx->cm_id, &sa_path, 1);
+	if (ret)
+		return ret;
+
+	memset(&event, 0, sizeof event);
+	event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
+	return ucma_event_handler(ctx->cm_id, &event);
+}
+
+static int ucma_set_option_ib(struct ucma_context *ctx, int optname,
+			      void *optval, size_t optlen)
+{
+	int ret;
+
+	switch (optname) {
+	case RDMA_OPTION_IB_PATH:
+		ret = ucma_set_ib_path(ctx, optval, optlen);
+		break;
+	default:
+		ret = -ENOSYS;
+	}
+
+	return ret;
+}
+
 static int ucma_set_option_level(struct ucma_context *ctx, int level,
 				 int optname, void *optval, size_t optlen)
 {
@@ -820,6 +866,9 @@  static int ucma_set_option_level(struct ucma_context *ctx, int level,
 	case RDMA_OPTION_ID:
 		ret = ucma_set_option_id(ctx, optname, optval, optlen);
 		break;
+	case RDMA_OPTION_IB:
+		ret = ucma_set_option_ib(ctx, optname, optval, optlen);
+		break;
 	default:
 		ret = -ENOSYS;
 	}
diff --git a/include/rdma/ib_sa.h b/include/rdma/ib_sa.h
index 3841c1a..1082afa 100644
--- a/include/rdma/ib_sa.h
+++ b/include/rdma/ib_sa.h
@@ -379,4 +379,10 @@  int ib_init_ah_from_path(struct ib_device *device, u8 port_num,
 			 struct ib_sa_path_rec *rec,
 			 struct ib_ah_attr *ah_attr);
 
+/**
+ * ib_sa_unpack_path - Convert a path record from MAD format to struct
+ * ib_sa_path_rec.
+ */
+void ib_sa_unpack_path(void *attribute, struct ib_sa_path_rec *rec);
+
 #endif /* IB_SA_H */
diff --git a/include/rdma/ib_user_sa.h b/include/rdma/ib_user_sa.h
index 6591201..cfc7c9b 100644
--- a/include/rdma/ib_user_sa.h
+++ b/include/rdma/ib_user_sa.h
@@ -35,6 +35,22 @@ 
 
 #include <linux/types.h>
 
+enum {
+	IB_PATH_GMP		= 1,
+	IB_PATH_PRIMARY		= (1<<1),
+	IB_PATH_ALTERNATE	= (1<<2),
+	IB_PATH_OUTBOUND	= (1<<3),
+	IB_PATH_INBOUND		= (1<<4),
+	IB_PATH_INBOUND_REVERSE = (1<<5),
+	IB_PATH_BIDIRECTIONAL	= IB_PATH_OUTBOUND | IB_PATH_INBOUND_REVERSE
+};
+
+struct ib_path_rec_data {
+	__u32	flags;
+	__u32	reserved;
+	__u32	path_rec[16];
+};
+
 struct ib_user_path_rec {
 	__u8	dgid[16];
 	__u8	sgid[16];
diff --git a/include/rdma/rdma_user_cm.h b/include/rdma/rdma_user_cm.h
index c557054..d7829f4 100644
--- a/include/rdma/rdma_user_cm.h
+++ b/include/rdma/rdma_user_cm.h
@@ -215,12 +215,15 @@  struct rdma_ucm_event_resp {
 
 /* Option levels */
 enum {
-	RDMA_OPTION_ID		= 0
+	RDMA_OPTION_ID		= 0,
+	RDMA_OPTION_IB		= 1
 };
 
 /* Option details */
 enum {
-	RDMA_OPTION_ID_TOS	= 0
+	RDMA_OPTION_ID_TOS	= 0,
+
+	RDMA_OPTION_IB_PATH	= 1
 };
 
 struct rdma_ucm_set_option {