Helen Chao <helen.chao@xxxxxxxxxx> noticed that when a user traverses a referral on an NFS/RDMA mount, the resulting submount always uses TCP. This behavior does not match the vers= setting when traversing a referral (vers=4.1 is preserved). It also does not match the behavior of crossing from the pseudofs into a real filesystem (proto=rdma is preserved in that case). The Linux NFS client does not currently support the fs_locations_info attribute. The situation is similar for all NFSv4 servers I know of. Therefore until the community has broad support for fs_locations_info, when following a referral: - First try to connect with RPC-over-RDMA. This will fail quickly if the client has no RDMA-capable interfaces. - If connecting with RPC-over-RDMA fails, or the RPC-over-RDMA transport is not available, use TCP. Reported-by: Helen Chao <helen.chao@xxxxxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/nfs/nfs4client.c | 23 ++++++++++++++++++++--- fs/nfs/nfs4namespace.c | 2 -- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c index 12bbab0..a3d5592 100644 --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -1114,19 +1114,36 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data, /* Initialise the client representation from the parent server */ nfs_server_copy_userdata(server, parent_server); - /* Get a client representation. - * Note: NFSv4 always uses TCP, */ + /* Get a client representation */ +#ifdef CONFIG_SUNRPC_XPRT_RDMA + rpc_set_port(data->addr, NFS_RDMA_PORT); error = nfs4_set_client(server, data->hostname, data->addr, data->addrlen, parent_client->cl_ipaddr, - rpc_protocol(parent_server->client), + XPRT_TRANSPORT_RDMA, + parent_server->client->cl_timeout, + parent_client->cl_mvops->minor_version, + parent_client->cl_net); + if (!error) + goto init_server; +#endif /* CONFIG_SUNRPC_XPRT_RDMA */ + + rpc_set_port(data->addr, NFS_PORT); + error = nfs4_set_client(server, data->hostname, + data->addr, + data->addrlen, + parent_client->cl_ipaddr, + XPRT_TRANSPORT_TCP, parent_server->client->cl_timeout, parent_client->cl_mvops->minor_version, parent_client->cl_net); if (error < 0) goto error; +#ifdef CONFIG_SUNRPC_XPRT_RDMA +init_server: +#endif error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor); if (error < 0) goto error; diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index 8c3f327..24f06dc 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -270,8 +270,6 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata, if (mountdata->addrlen == 0) continue; - rpc_set_port(mountdata->addr, NFS_PORT); - memcpy(page2, buf->data, buf->len); page2[buf->len] = '\0'; mountdata->hostname = page2; -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
