@@ -34,6 +34,17 @@ static int so_priority;
module_param(so_priority, int, 0644);
MODULE_PARM_DESC(so_priority, "nvme tcp socket optimize priority");
+#ifdef CONFIG_ULP_DDP
+/* NVMeTCP direct data placement and data digest offload will not
+ * happen if this parameter false (default), regardless of what the
+ * underlying netdev capabilities are.
+ */
+static bool ulp_offload;
+module_param(ulp_offload, bool, 0644);
+MODULE_PARM_DESC(ulp_offload, "Enable or disable NVMeTCP ULP support");
+#endif
+
+
#ifdef CONFIG_DEBUG_LOCK_ALLOC
/* lockdep can detect a circular dependency of the form
* sk_lock -> mmap_lock (page fault) -> fs locks -> sk_lock
@@ -298,6 +309,9 @@ static bool nvme_tcp_ddp_query_limits(struct net_device *netdev,
{
int ret;
+ if (!ulp_offload)
+ return false;
+
if (!netdev || !(netdev->features & NETIF_F_HW_ULP_DDP) ||
!netdev->ulp_ddp_ops || !netdev->ulp_ddp_ops->ulp_ddp_limits)
return false;
@@ -497,6 +511,9 @@ static int nvme_tcp_offload_limits(struct nvme_tcp_queue *queue, struct net_devi
{
struct nvme_tcp_ddp_limits limits = {{ULP_DDP_NVME}};
+ if (!ulp_offload)
+ return 0;
+
if (!nvme_tcp_ddp_query_limits(netdev, &limits)) {
queue->ctrl->offloading_netdev = NULL;
return -EOPNOTSUPP;
Add ulp_offload module parameter to the nvme-tcp module to control ULP offload at the NVMe-TCP layer. Turn ULP offload off be default, regardless of the NIC driver support. In summary, to enable ULP offload: - nvme-tcp modparam must be set to 1 - the NIC driver must set - NETIF_F_HW_ULP_DDP flag in netdev->features - ULP_DDP_C_NVME_TCP and/or ULP_DDP_C_NVME_TCP_DDGST_RX flags in ulp_limits->offload_capabilities Signed-off-by: Yoray Zack <yorayz@nvidia.com> Signed-off-by: Shai Malin <smalin@nvidia.com> Signed-off-by: Aurelien Aptel <aaptel@nvidia.com> --- drivers/nvme/host/tcp.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)