[PATCH net-next v5 6/7] net: devmem: add ring parameter filtering

Taehee Yoo
2024-11-13T17:33:32Z

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
header-data-split-thresh value should be 0.

Tested-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
---

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 | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)

diff --git a/net/core/devmem.c b/net/core/devmem.c
index 11b91c12ee11..3425e872e87a 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 +144,20 @@ int net_devmem_bind_dmabuf_to_queue(struct net_device *dev, u32 rxq_idx,
return -ERANGE;
}

+ if (!dev->ethtool_ops->get_ringparam)
+ return -EOPNOTSUPP;
+
+ dev->ethtool_ops->get_ringparam(dev, &ringparam, &kernel_ringparam,
+ extack);
+ if (kernel_ringparam.tcp_data_split != ETHTOOL_TCP_DATA_SPLIT_ENABLED) {
+ NL_SET_ERR_MSG(extack, "tcp-data-split is disabled");
+ return -EINVAL;
+ }
+ if (kernel_ringparam.hds_thresh) {
+ NL_SET_ERR_MSG(extack, "header-data-split-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");
--
2.34.1