[PATCH net-next 2/7] ethtool: provide message mask with DEBUG_GET request

From: Michal Kubecek
Date: Sun Jan 26 2020 - 17:11:37 EST

Implement DEBUG_GET request to get debugging settings for a device. At the
moment, only message mask corresponding to message level as reported by
ETHTOOL_GMSGLVL ioctl request is provided. (It is called message level in
ioctl interface but almost all drivers interpret it as a bit mask.)

As part of the implementation, provide symbolic names for message mask bits
as ETH_SS_MSG_CLASSES string set.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
---
Documentation/networking/ethtool-netlink.rst | 34 ++++++++-
include/linux/netdevice.h | 56 ++++++++++----
include/uapi/linux/ethtool.h | 2 +
include/uapi/linux/ethtool_netlink.h | 14 ++++
net/ethtool/Makefile | 2 +-
net/ethtool/common.c | 19 +++++
net/ethtool/common.h | 1 +
net/ethtool/debug.c | 80 ++++++++++++++++++++
net/ethtool/netlink.c | 8 ++
net/ethtool/netlink.h | 1 +
net/ethtool/strset.c | 5 ++
11 files changed, 205 insertions(+), 17 deletions(-)
create mode 100644 net/ethtool/debug.c

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index c60afba69e3c..76a411d3102d 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -185,6 +185,7 @@ Userspace to kernel:
``ETHTOOL_MSG_LINKMODES_GET`` get link modes info
``ETHTOOL_MSG_LINKMODES_SET`` set link modes info
``ETHTOOL_MSG_LINKSTATE_GET`` get link state
+ ``ETHTOOL_MSG_DEBUG_GET`` get debugging settings
===================================== ================================

Kernel to userspace:
@@ -196,6 +197,7 @@ Kernel to userspace:
``ETHTOOL_MSG_LINKMODES_GET_REPLY`` link modes info
``ETHTOOL_MSG_LINKMODES_NTF`` link modes notification
``ETHTOOL_MSG_LINKSTATE_GET_REPLY`` link state info
+ ``ETHTOOL_MSG_DEBUG_GET_REPLY`` debugging settings
===================================== ================================

``GET`` requests are sent by userspace applications to retrieve device
@@ -423,6 +425,36 @@ define their own handler.
devices supporting the request).


+DEBUG_GET
+=========
+
+Requests debugging settings of a device. At the moment, only message mask is
+provided.
+
+Request contents:
+
+ ==================================== ====== ==========================
+ ``ETHTOOL_A_DEBUG_HEADER`` nested request header
+ ==================================== ====== ==========================
+
+Kernel response contents:
+
+ ==================================== ====== ==========================
+ ``ETHTOOL_A_DEBUG_HEADER`` nested reply header
+ ``ETHTOOL_A_DEBUG_MSGMASK`` bitset message mask
+ ==================================== ====== ==========================
+
+The message mask (``ETHTOOL_A_DEBUG_MSGMASK``) is equal to message level as
+provided by ``ETHTOOL_GMSGLVL`` and set by ``ETHTOOL_SMSGLVL`` in ioctl
+interface. While it is called message level there for historical reasons, most
+drivers and almost all newer drivers use it as a mask of enabled message
+classes (represented by ``NETIF_MSG_*`` constants); therefore netlink
+interface follows its actual use in practice.
+
+``DEBUG_GET`` allows dump requests (kernel returns reply messages for all
+devices supporting the request).
+
+
Request translation
===================

@@ -441,7 +473,7 @@ have their netlink replacement yet.
``ETHTOOL_GREGS`` n/a
``ETHTOOL_GWOL`` n/a
``ETHTOOL_SWOL`` n/a
- ``ETHTOOL_GMSGLVL`` n/a
+ ``ETHTOOL_GMSGLVL`` ``ETHTOOL_MSG_DEBUG_GET``
``ETHTOOL_SMSGLVL`` n/a
``ETHTOOL_NWAY_RST`` n/a
``ETHTOOL_GLINK`` ``ETHTOOL_MSG_LINKSTATE_GET``
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 78e9c6c1b131..bdec77b7bec3 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3894,22 +3894,48 @@ void netif_device_attach(struct net_device *dev);
*/

enum {
- NETIF_MSG_DRV = 0x0001,
- NETIF_MSG_PROBE = 0x0002,
- NETIF_MSG_LINK = 0x0004,
- NETIF_MSG_TIMER = 0x0008,
- NETIF_MSG_IFDOWN = 0x0010,
- NETIF_MSG_IFUP = 0x0020,
- NETIF_MSG_RX_ERR = 0x0040,
- NETIF_MSG_TX_ERR = 0x0080,
- NETIF_MSG_TX_QUEUED = 0x0100,
- NETIF_MSG_INTR = 0x0200,
- NETIF_MSG_TX_DONE = 0x0400,
- NETIF_MSG_RX_STATUS = 0x0800,
- NETIF_MSG_PKTDATA = 0x1000,
- NETIF_MSG_HW = 0x2000,
- NETIF_MSG_WOL = 0x4000,
+ NETIF_MSG_DRV_BIT,
+ NETIF_MSG_PROBE_BIT,
+ NETIF_MSG_LINK_BIT,
+ NETIF_MSG_TIMER_BIT,
+ NETIF_MSG_IFDOWN_BIT,
+ NETIF_MSG_IFUP_BIT,
+ NETIF_MSG_RX_ERR_BIT,
+ NETIF_MSG_TX_ERR_BIT,
+ NETIF_MSG_TX_QUEUED_BIT,
+ NETIF_MSG_INTR_BIT,
+ NETIF_MSG_TX_DONE_BIT,
+ NETIF_MSG_RX_STATUS_BIT,
+ NETIF_MSG_PKTDATA_BIT,
+ NETIF_MSG_HW_BIT,
+ NETIF_MSG_WOL_BIT,
+
+ /* When you add a new bit above, update netif_msg_class_names array
+ * in net/ethtool/common.c
+ */
+ NETIF_MSG_CLASS_COUNT,
};
+/* Both ethtool_ops interface and internal driver implementation use u32 */
+static_assert(NETIF_MSG_CLASS_COUNT <= 32);
+
+#define __NETIF_MSG_BIT(bit) ((u32)1 << (bit))
+#define __NETIF_MSG(name) __NETIF_MSG_BIT(NETIF_MSG_ ## name ## _BIT)
+
+#define NETIF_MSG_DRV __NETIF_MSG(DRV)
+#define NETIF_MSG_PROBE __NETIF_MSG(PROBE)
+#define NETIF_MSG_LINK __NETIF_MSG(LINK)
+#define NETIF_MSG_TIMER __NETIF_MSG(TIMER)
+#define NETIF_MSG_IFDOWN __NETIF_MSG(IFDOWN)
+#define NETIF_MSG_IFUP __NETIF_MSG(IFUP)
+#define NETIF_MSG_RX_ERR __NETIF_MSG(RX_ERR)
+#define NETIF_MSG_TX_ERR __NETIF_MSG(TX_ERR)
+#define NETIF_MSG_TX_QUEUED __NETIF_MSG(TX_QUEUED)
+#define NETIF_MSG_INTR __NETIF_MSG(INTR)
+#define NETIF_MSG_TX_DONE __NETIF_MSG(TX_DONE)
+#define NETIF_MSG_RX_STATUS __NETIF_MSG(RX_STATUS)
+#define NETIF_MSG_PKTDATA __NETIF_MSG(PKTDATA)
+#define NETIF_MSG_HW __NETIF_MSG(HW)
+#define NETIF_MSG_WOL __NETIF_MSG(WOL)

#define netif_msg_drv(p) ((p)->msg_enable & NETIF_MSG_DRV)
#define netif_msg_probe(p) ((p)->msg_enable & NETIF_MSG_PROBE)
diff --git a/include/uapi/linux/ethtool.h b/include/uapi/linux/ethtool.h
index 116bcbf09c74..456fb2aa0fad 100644
--- a/include/uapi/linux/ethtool.h
+++ b/include/uapi/linux/ethtool.h
@@ -594,6 +594,7 @@ struct ethtool_pauseparam {
* @ETH_SS_PHY_STATS: Statistic names, for use with %ETHTOOL_GPHYSTATS
* @ETH_SS_PHY_TUNABLES: PHY tunable names
* @ETH_SS_LINK_MODES: link mode names
+ * @ETH_SS_MSG_CLASSES: debug message class names
*/
enum ethtool_stringset {
ETH_SS_TEST = 0,
@@ -606,6 +607,7 @@ enum ethtool_stringset {
ETH_SS_PHY_STATS,
ETH_SS_PHY_TUNABLES,
ETH_SS_LINK_MODES,
+ ETH_SS_MSG_CLASSES,

/* add new constants above here */
ETH_SS_COUNT
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 02f82f42a889..0d39e04567cb 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -20,6 +20,7 @@ enum {
ETHTOOL_MSG_LINKMODES_GET,
ETHTOOL_MSG_LINKMODES_SET,
ETHTOOL_MSG_LINKSTATE_GET,
+ ETHTOOL_MSG_DEBUG_GET,

/* add new constants above here */
__ETHTOOL_MSG_USER_CNT,
@@ -35,6 +36,7 @@ enum {
ETHTOOL_MSG_LINKMODES_GET_REPLY,
ETHTOOL_MSG_LINKMODES_NTF,
ETHTOOL_MSG_LINKSTATE_GET_REPLY,
+ ETHTOOL_MSG_DEBUG_GET_REPLY,

/* add new constants above here */
__ETHTOOL_MSG_KERNEL_CNT,
@@ -195,6 +197,18 @@ enum {
ETHTOOL_A_LINKSTATE_MAX = __ETHTOOL_A_LINKSTATE_CNT - 1
};

+/* DEBUG */
+
+enum {
+ ETHTOOL_A_DEBUG_UNSPEC,
+ ETHTOOL_A_DEBUG_HEADER, /* nest - _A_HEADER_* */
+ ETHTOOL_A_DEBUG_MSGMASK, /* bitset */
+
+ /* add new constants above here */
+ __ETHTOOL_A_DEBUG_CNT,
+ ETHTOOL_A_DEBUG_MAX = __ETHTOOL_A_DEBUG_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 9a1332fb0cc6..c120c820a4f5 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -5,4 +5,4 @@ obj-y += ioctl.o common.o
obj-$(CONFIG_ETHTOOL_NETLINK) += ethtool_nl.o

ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o \
- linkstate.o
+ linkstate.o debug.o
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index e621b1694d2f..93a46c640181 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -170,6 +170,25 @@ const char link_mode_names[][ETH_GSTRING_LEN] = {
};
static_assert(ARRAY_SIZE(link_mode_names) == __ETHTOOL_LINK_MODE_MASK_NBITS);

+const char netif_msg_class_names[][ETH_GSTRING_LEN] = {
+ [NETIF_MSG_DRV_BIT] = "drv",
+ [NETIF_MSG_PROBE_BIT] = "probe",
+ [NETIF_MSG_LINK_BIT] = "link",
+ [NETIF_MSG_TIMER_BIT] = "timer",
+ [NETIF_MSG_IFDOWN_BIT] = "ifdown",
+ [NETIF_MSG_IFUP_BIT] = "ifup",
+ [NETIF_MSG_RX_ERR_BIT] = "rx_err",
+ [NETIF_MSG_TX_ERR_BIT] = "tx_err",
+ [NETIF_MSG_TX_QUEUED_BIT] = "tx_queued",
+ [NETIF_MSG_INTR_BIT] = "intr",
+ [NETIF_MSG_TX_DONE_BIT] = "tx_done",
+ [NETIF_MSG_RX_STATUS_BIT] = "rx_status",
+ [NETIF_MSG_PKTDATA_BIT] = "pktdata",
+ [NETIF_MSG_HW_BIT] = "hw",
+ [NETIF_MSG_WOL_BIT] = "wol",
+};
+static_assert(ARRAY_SIZE(netif_msg_class_names) == NETIF_MSG_CLASS_COUNT);
+
/* return false if legacy contained non-0 deprecated fields
* maxtxpkt/maxrxpkt. rest of ksettings always updated
*/
diff --git a/net/ethtool/common.h b/net/ethtool/common.h
index 5c5f7dc90cd4..064c5c3aa990 100644
--- a/net/ethtool/common.h
+++ b/net/ethtool/common.h
@@ -19,6 +19,7 @@ tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN];
extern const char
phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN];
extern const char link_mode_names[][ETH_GSTRING_LEN];
+extern const char netif_msg_class_names[][ETH_GSTRING_LEN];

int __ethtool_get_link(struct net_device *dev);

diff --git a/net/ethtool/debug.c b/net/ethtool/debug.c
new file mode 100644
index 000000000000..cc121a23be5f
--- /dev/null
+++ b/net/ethtool/debug.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+#include "bitset.h"
+
+struct debug_req_info {
+ struct ethnl_req_info base;
+};
+
+struct debug_reply_data {
+ struct ethnl_reply_data base;
+ u32 msg_mask;
+};
+
+#define DEBUG_REPDATA(__reply_base) \
+ container_of(__reply_base, struct debug_reply_data, base)
+
+static const struct nla_policy
+debug_get_policy[ETHTOOL_A_DEBUG_MAX + 1] = {
+ [ETHTOOL_A_DEBUG_UNSPEC] = { .type = NLA_REJECT },
+ [ETHTOOL_A_DEBUG_HEADER] = { .type = NLA_NESTED },
+ [ETHTOOL_A_DEBUG_MSGMASK] = { .type = NLA_REJECT },
+};
+
+static int debug_prepare_data(const struct ethnl_req_info *req_base,
+ struct ethnl_reply_data *reply_base,
+ struct genl_info *info)
+{
+ struct debug_reply_data *data = DEBUG_REPDATA(reply_base);
+ struct net_device *dev = reply_base->dev;
+ int ret;
+
+ if (!dev->ethtool_ops->get_msglevel)
+ return -EOPNOTSUPP;
+
+ ret = ethnl_ops_begin(dev);
+ if (ret < 0)
+ return ret;
+ data->msg_mask = dev->ethtool_ops->get_msglevel(dev);
+ ethnl_ops_complete(dev);
+
+ return 0;
+}
+
+static int debug_reply_size(const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct debug_reply_data *data = DEBUG_REPDATA(reply_base);
+ bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+
+ return ethnl_bitset32_size(&data->msg_mask, NULL, NETIF_MSG_CLASS_COUNT,
+ netif_msg_class_names, compact);
+}
+
+static int debug_fill_reply(struct sk_buff *skb,
+ const struct ethnl_req_info *req_base,
+ const struct ethnl_reply_data *reply_base)
+{
+ const struct debug_reply_data *data = DEBUG_REPDATA(reply_base);
+ bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
+
+ return ethnl_put_bitset32(skb, ETHTOOL_A_DEBUG_MSGMASK, &data->msg_mask,
+ NULL, NETIF_MSG_CLASS_COUNT,
+ netif_msg_class_names, compact);
+}
+
+const struct ethnl_request_ops ethnl_debug_request_ops = {
+ .request_cmd = ETHTOOL_MSG_DEBUG_GET,
+ .reply_cmd = ETHTOOL_MSG_DEBUG_GET_REPLY,
+ .hdr_attr = ETHTOOL_A_DEBUG_HEADER,
+ .max_attr = ETHTOOL_A_DEBUG_MAX,
+ .req_info_size = sizeof(struct debug_req_info),
+ .reply_data_size = sizeof(struct debug_reply_data),
+ .request_policy = debug_get_policy,
+
+ .prepare_data = debug_prepare_data,
+ .reply_size = debug_reply_size,
+ .fill_reply = debug_fill_reply,
+};
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 0af43bbdb9b2..bdaf583e392b 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -213,6 +213,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
[ETHTOOL_MSG_LINKINFO_GET] = &ethnl_linkinfo_request_ops,
[ETHTOOL_MSG_LINKMODES_GET] = &ethnl_linkmodes_request_ops,
[ETHTOOL_MSG_LINKSTATE_GET] = &ethnl_linkstate_request_ops,
+ [ETHTOOL_MSG_DEBUG_GET] = &ethnl_debug_request_ops,
};

static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -664,6 +665,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
.dumpit = ethnl_default_dumpit,
.done = ethnl_default_done,
},
+ {
+ .cmd = ETHTOOL_MSG_DEBUG_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 da9d6521a4eb..9bd8ef671501 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -334,6 +334,7 @@ extern const struct ethnl_request_ops ethnl_strset_request_ops;
extern const struct ethnl_request_ops ethnl_linkinfo_request_ops;
extern const struct ethnl_request_ops ethnl_linkmodes_request_ops;
extern const struct ethnl_request_ops ethnl_linkstate_request_ops;
+extern const struct ethnl_request_ops ethnl_debug_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/strset.c b/net/ethtool/strset.c
index 948d967f1eca..7a45c25355b8 100644
--- a/net/ethtool/strset.c
+++ b/net/ethtool/strset.c
@@ -50,6 +50,11 @@ static const struct strset_info info_template[] = {
.count = __ETHTOOL_LINK_MODE_MASK_NBITS,
.strings = link_mode_names,
},
+ [ETH_SS_MSG_CLASSES] = {
+ .per_dev = false,
+ .count = NETIF_MSG_CLASS_COUNT,
+ .strings = netif_msg_class_names,
+ },
};

struct strset_req_info {
--
2.25.0