[PATCH net-next v3 05/12] ethtool: provide pause parameters with PAUSE_GET request

From: Michal Kubecek
Date: Fri Mar 27 2020 - 19:01:38 EST

Implement PAUSE_GET request to get pause parameters of a network device.
These are traditionally available via ETHTOOL_GPAUSEPARAM ioctl request.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
---
Documentation/networking/ethtool-netlink.rst | 40 +++++++++-
include/uapi/linux/ethtool_netlink.h | 16 ++++
net/ethtool/Makefile | 2 +-
net/ethtool/netlink.c | 8 ++
net/ethtool/netlink.h | 1 +
net/ethtool/pause.c | 81 ++++++++++++++++++++
6 files changed, 146 insertions(+), 2 deletions(-)
create mode 100644 net/ethtool/pause.c

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index d4be0a63786d..43c7baf36b32 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -199,6 +199,7 @@ Userspace to kernel:
``ETHTOOL_MSG_CHANNELS_SET`` set channel counts
``ETHTOOL_MSG_COALESCE_GET`` get coalescing parameters
``ETHTOOL_MSG_COALESCE_SET`` set coalescing parameters
+ ``ETHTOOL_MSG_PAUSE_GET`` get pause parameters
===================================== ================================

Kernel to userspace:
@@ -225,6 +226,7 @@ Kernel to userspace:
``ETHTOOL_MSG_CHANNELS_NTF`` channel counts
``ETHTOOL_MSG_COALESCE_GET_REPLY`` coalescing parameters
``ETHTOOL_MSG_COALESCE_NTF`` coalescing parameters
+ ``ETHTOOL_MSG_PAUSE_GET_REPLY`` pause parameters
===================================== =================================

``GET`` requests are sent by userspace applications to retrieve device
@@ -832,6 +834,42 @@ is not set), regardless of their values. Driver may impose additional
constraints on coalescing parameters and their values.


+PAUSE_GET
+============
+
+Gets channel counts like ``ETHTOOL_GPAUSE`` ioctl request.
+
+Request contents:
+
+ ===================================== ====== ==========================
+ ``ETHTOOL_A_PAUSE_HEADER`` nested request header
+ ===================================== ====== ==========================
+
+Kernel response contents:
+
+ ===================================== ====== ==========================
+ ``ETHTOOL_A_PAUSE_HEADER`` nested request header
+ ``ETHTOOL_A_PAUSE_AUTONEG`` bool pause autonegotiation
+ ``ETHTOOL_A_PAUSE_RX`` bool receive pause frames
+ ``ETHTOOL_A_PAUSE_TX`` bool transmit pause frames
+ ===================================== ====== ==========================
+
+
+PAUSE_SET
+============
+
+Sets pause parameters like ``ETHTOOL_GPAUSEPARAM`` ioctl request.
+
+Request contents:
+
+ ===================================== ====== ==========================
+ ``ETHTOOL_A_PAUSE_HEADER`` nested request header
+ ``ETHTOOL_A_PAUSE_AUTONEG`` bool pause autonegotiation
+ ``ETHTOOL_A_PAUSE_RX`` bool receive pause frames
+ ``ETHTOOL_A_PAUSE_TX`` bool transmit pause frames
+ ===================================== ====== ==========================
+
+
Request translation
===================

@@ -860,7 +898,7 @@ have their netlink replacement yet.
``ETHTOOL_SCOALESCE`` ``ETHTOOL_MSG_COALESCE_SET``
``ETHTOOL_GRINGPARAM`` ``ETHTOOL_MSG_RINGS_GET``
``ETHTOOL_SRINGPARAM`` ``ETHTOOL_MSG_RINGS_SET``
- ``ETHTOOL_GPAUSEPARAM`` n/a
+ ``ETHTOOL_GPAUSEPARAM`` ``ETHTOOL_MSG_PAUSE_GET``
``ETHTOOL_SPAUSEPARAM`` n/a
``ETHTOOL_GRXCSUM`` ``ETHTOOL_MSG_FEATURES_GET``
``ETHTOOL_SRXCSUM`` ``ETHTOOL_MSG_FEATURES_SET``
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index fdbcaf76df1e..1c8d1228f63f 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -34,6 +34,7 @@ enum {
ETHTOOL_MSG_CHANNELS_SET,
ETHTOOL_MSG_COALESCE_GET,
ETHTOOL_MSG_COALESCE_SET,
+ ETHTOOL_MSG_PAUSE_GET,

/* add new constants above here */
__ETHTOOL_MSG_USER_CNT,
@@ -64,6 +65,7 @@ enum {
ETHTOOL_MSG_CHANNELS_NTF,
ETHTOOL_MSG_COALESCE_GET_REPLY,
ETHTOOL_MSG_COALESCE_NTF,
+ ETHTOOL_MSG_PAUSE_GET_REPLY,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
@@ -347,6 +349,20 @@ enum {
ETHTOOL_A_COALESCE_MAX = (__ETHTOOL_A_COALESCE_CNT - 1)
};

+/* PAUSE */
+
+enum {
+ ETHTOOL_A_PAUSE_UNSPEC,
+ ETHTOOL_A_PAUSE_HEADER, /* nest - _A_HEADER_* */
+ ETHTOOL_A_PAUSE_AUTONEG, /* u8 */
+ ETHTOOL_A_PAUSE_RX, /* u8 */
+ ETHTOOL_A_PAUSE_TX, /* u8 */
+
+ /* add new constants above here */
+ __ETHTOOL_A_PAUSE_CNT,
+ ETHTOOL_A_PAUSE_MAX = (__ETHTOOL_A_PAUSE_CNT - 1)
+};
+
/* generic netlink info */
#define ETHTOOL_GENL_NAME "ethtool"
#define ETHTOOL_GENL_VERSION 1
diff --git a/net/ethtool/Makefile b/net/ethtool/Makefile
index 7f7f40e03d16..28589ad5fd8a 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -6,4 +6,4 @@ obj-$(CONFIG_ETHTOOL_NETLINK) += ethtool_nl.o

ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o \
linkstate.o debug.o wol.o features.o privflags.o rings.o \
- channels.o coalesce.o
+ channels.o coalesce.o pause.o
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 117971e695ca..ca1695de8c9d 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -228,6 +228,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
[ETHTOOL_MSG_RINGS_GET] = &ethnl_rings_request_ops,
[ETHTOOL_MSG_CHANNELS_GET] = &ethnl_channels_request_ops,
[ETHTOOL_MSG_COALESCE_GET] = &ethnl_coalesce_request_ops,
+ [ETHTOOL_MSG_PAUSE_GET] = &ethnl_pause_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -801,6 +802,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
.flags = GENL_UNS_ADMIN_PERM,
.doit = ethnl_set_coalesce,
},
+ {
+ .cmd = ETHTOOL_MSG_PAUSE_GET,
+ .doit = ethnl_default_doit,
+ .start = ethnl_default_start,
+ .dumpit = ethnl_default_dumpit,
+ .done = ethnl_default_done,
+ },
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index c3fb4fe5a3b7..e14ac089bfb1 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -342,6 +342,7 @@ extern const struct ethnl_request_ops ethnl_privflags_request_ops;
extern const struct ethnl_request_ops ethnl_rings_request_ops;
extern const struct ethnl_request_ops ethnl_channels_request_ops;
extern const struct ethnl_request_ops ethnl_coalesce_request_ops;
+extern const struct ethnl_request_ops ethnl_pause_request_ops;

int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info);
int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);
diff --git a/net/ethtool/pause.c b/net/ethtool/pause.c
new file mode 100644
index 000000000000..9feafeb7bb1c
--- /dev/null
+++ b/net/ethtool/pause.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+
+struct pause_req_info {
+ struct ethnl_req_info base;
+};
+
+struct pause_reply_data {
+ struct ethnl_reply_data base;
+ struct ethtool_pauseparam pauseparam;
+};
+
+#define PAUSE_REPDATA(__reply_base) \
+ container_of(__reply_base, struct pause_reply_data, base)
+
+static const struct nla_policy
+pause_get_policy[ETHTOOL_A_PAUSE_MAX + 1] = {
+ [ETHTOOL_A_PAUSE_UNSPEC] = { .type = NLA_REJECT },
+ [ETHTOOL_A_PAUSE_HEADER] = { .type = NLA_NESTED },
+ [ETHTOOL_A_PAUSE_AUTONEG] = { .type = NLA_REJECT },
+ [ETHTOOL_A_PAUSE_RX] = { .type = NLA_REJECT },
+ [ETHTOOL_A_PAUSE_TX] = { .type = NLA_REJECT },
+};
+
+static int pause_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct pause_reply_data *data = PAUSE_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ int ret;
+
+ if (!dev->ethtool_ops->get_pauseparam)
+ return -EOPNOTSUPP;
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ return ret;
+ dev->ethtool_ops->get_pauseparam(dev, &data->pauseparam);
+ ethnl_ops_complete(dev);
+
+ return 0;
+}
+
+static int pause_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ return nla_total_size(sizeof(u8)) + /* _PAUSE_AUTONEG */
+ nla_total_size(sizeof(u8)) + /* _PAUSE_RX */
+ nla_total_size(sizeof(u8)); /* _PAUSE_TX */
+}
+
+static int pause_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct pause_reply_data *data = PAUSE_REPDATA(reply_base);
+ const struct ethtool_pauseparam *pauseparam = &data->pauseparam;
+
+ if (nla_put_u8(skb, ETHTOOL_A_PAUSE_AUTONEG, !!pauseparam->autoneg) ||
+ nla_put_u8(skb, ETHTOOL_A_PAUSE_RX, !!pauseparam->rx_pause) ||
+ nla_put_u8(skb, ETHTOOL_A_PAUSE_TX, !!pauseparam->tx_pause))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+const struct ethnl_request_ops ethnl_pause_request_ops = {
+ .request_cmd = ETHTOOL_MSG_PAUSE_GET,
+ .reply_cmd = ETHTOOL_MSG_PAUSE_GET_REPLY,
+ .hdr_attr = ETHTOOL_A_PAUSE_HEADER,
+ .max_attr = ETHTOOL_A_PAUSE_MAX,
+ .req_info_size = sizeof(struct pause_req_info),
+ .reply_data_size = sizeof(struct pause_reply_data),
+ .request_policy = pause_get_policy,
+
+ .prepare_data = pause_prepare_data,
+ .reply_size = pause_reply_size,
+ .fill_reply = pause_fill_reply,
+};
--
2.25.1