[net-next,v6,6/9] net: devmem: add ring parameter filtering

Commit Message

Taehee Yoo Dec. 18, 2024, 2:45 p.m. UTC

If driver doesn't support ring parameter or tcp-data-split configuration
is not sufficient, the devmem should not be set up.
Before setup the devmem, tcp-data-split should be ON and hds-thresh
value should be 0.

Tested-by: Stanislav Fomichev <[e-mail]>
Reviewed-by: Mina Almasry <[e-mail]>
Signed-off-by: Taehee Yoo <[e-mail]>
---

v6:
 - No changes.

v5:
 - Add Review tag from Mina.

v4:
 - Check condition before __netif_get_rx_queue().
 - Separate condition check.
 - Add Test tag from Stanislav.

v3:
 - Patch added.

 net/core/devmem.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

Patch

diff --git a/net/core/devmem.c b/net/core/devmem.c
index 0b6ed7525b22..a29333af3ebd 100644
--- a/net/core/devmem.c
+++ b/net/core/devmem.c
@@ -8,6 +8,8 @@ 
  */
 
 #include <linux/dma-buf.h>
+#include <linux/ethtool.h>
+#include <linux/ethtool_netlink.h>
 #include <linux/genalloc.h>
 #include <linux/mm.h>
 #include <linux/netdevice.h>
@@ -131,6 +133,8 @@  int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 				    struct net_devmem_dmabuf_binding *binding,
 				    struct netlink_ext_ack *extack)
 {
+	struct kernel_ethtool_ringparam kernel_ringparam = {};
+	struct ethtool_ringparam ringparam = {};
 	struct netdev_rx_queue *rxq;
 	u32 xa_idx;
 	int err;
@@ -140,6 +144,21 @@  int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
 		return -ERANGE;
 	}
 
+	if (dev->ethtool->hds_config != ETHTOOL_TCP_DATA_SPLIT_ENABLED) {
+		NL_SET_ERR_MSG(extack, "tcp-data-split is disabled");
+		return -EINVAL;
+	}
+
+	if (!dev->ethtool_ops->get_ringparam)
+		return -EOPNOTSUPP;
+
+	dev->ethtool_ops->get_ringparam(dev, &ringparam, &kernel_ringparam,
+					extack);
+	if (kernel_ringparam.hds_thresh) {
+		NL_SET_ERR_MSG(extack, "hds-thresh is not zero");
+		return -EINVAL;
+	}
+
 	rxq = __netif_get_rx_queue(dev, rxq_idx);
 	if (rxq->mp_params.mp_priv) {
 		NL_SET_ERR_MSG(extack, "designated queue already memory provider bound");