[RFC PATCH net-next v3 11/21] ethtool: provide driver/device information in GET_INFO request

From: Michal Kubecek
Date: Mon Feb 18 2019 - 13:22:25 EST

Implement GET_INFO request to get basic driver and device information as
provided by ETHTOOL_GDRVINFO ioct command. The information is read only so
that the corresponding SET_INFO message is only used in kernel replies.

Move most of ethtool_get_drvinfo() int common.c so that the code can be
shared by both ioctl and netlink interface.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
---
Documentation/networking/ethtool-netlink.txt | 43 ++++-
include/uapi/linux/ethtool_netlink.h | 32 ++++
net/ethtool/Makefile | 2 +-
net/ethtool/common.c | 54 +++++++
net/ethtool/common.h | 2 +
net/ethtool/info.c | 155 +++++++++++++++++++
net/ethtool/ioctl.c | 52 +------
net/ethtool/netlink.c | 9 ++
8 files changed, 300 insertions(+), 49 deletions(-)
create mode 100644 net/ethtool/info.c

diff --git a/Documentation/networking/ethtool-netlink.txt b/Documentation/networking/ethtool-netlink.txt
index f0fe4f50db9f..b6999a2167e8 100644
--- a/Documentation/networking/ethtool-netlink.txt
+++ b/Documentation/networking/ethtool-netlink.txt
@@ -128,6 +128,8 @@ List of message types
ETHNL_CMD_EVENT notification only
ETHNL_CMD_GET_STRSET
ETHNL_CMD_SET_STRSET response only
+ ETHNL_CMD_GET_INFO
+ ETHNL_CMD_SET_INFO response only

All constants use ETHNL_CMD_ prefix, usually followed by "GET", "SET" or "ACT"
to indicate the type.
@@ -208,6 +210,45 @@ ETHA_STRSET_COUNTS tells kernel to only return string counts of the sets, not
the actual strings.


+GET_INFO
+--------
+
+GET_INFO requests information provided by ioctl commands ETHTOOL_GDRVINFO,
+ETHTOOL_GPERMADDR and ETHTOOL_GET_TS_INFO to provide basic device information.
+Common pattern is that all information is read only so that SET_INFO message
+exists but is only used by kernel for replies to GET_INFO requests. There is
+also no corresponding notification.
+
+Request contents:
+
+ ETHA_INFO_DEV (nested) device identification
+ ETHA_INFO_INFOMASK (u32) info mask
+ ETHA_INFO_COMPACT (flag) request compact bitsets
+
+Info mask bits meaning:
+
+ ETH_INFO_IM_DRVINFO driver info (GDRVINFO)
+ ETH_INFO_IM_PERMADDR permanent HW address (GPERMADDR)
+ ETH_INFO_IM_TSINFO timestamping info (GET_TS_INFO)
+
+Kernel response contents:
+
+ ETHA_INFO_DEV (nested) device identification
+ ETHA_INFO_DRVINFO (nested) driver information
+ ETHA_DRVINFO_DRIVER (string) driver name
+ ETHA_DRVINFO_FWVERSION (string) firmware version
+ ETHA_DRVINFO_BUSINFO (string) device bus address
+ ETHA_DRVINFO_EROM_VER (string) expansion ROM version
+
+The meaning of DRVINFO attributes follows the corresponding fields of
+ETHTOOL_GDRVINFO response. Second part with various counts and sizes is
+omitted as these are not really needed (and if they are, they can be easily
+found by different means). Driver version is also omitted as it is rather
+misleading in most cases.
+
+GET_INFO requests allow dumps.
+
+
Request translation
-------------------

@@ -219,7 +260,7 @@ ioctl command netlink command
---------------------------------------------------------------------
ETHTOOL_GSET n/a
ETHTOOL_SSET n/a
-ETHTOOL_GDRVINFO n/a
+ETHTOOL_GDRVINFO ETHNL_CMD_GET_INFO
ETHTOOL_GREGS n/a
ETHTOOL_GWOL n/a
ETHTOOL_SWOL n/a
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 630b66732dc9..fdae12b6c6b6 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -10,6 +10,8 @@ enum {
ETHNL_CMD_EVENT, /* only for notifications */
ETHNL_CMD_GET_STRSET,
ETHNL_CMD_SET_STRSET, /* only for reply */
+ ETHNL_CMD_GET_INFO,
+ ETHNL_CMD_SET_INFO, /* only for reply */

__ETHNL_CMD_CNT,
ETHNL_CMD_MAX = (__ETHNL_CMD_CNT - 1)
@@ -135,6 +137,36 @@ enum {
ETHA_STRSET_MAX = (__ETHA_STRSET_CNT - 1)
};

+/* GET_INFO / SET_INFO */
+
+enum {
+ ETHA_INFO_UNSPEC,
+ ETHA_INFO_DEV, /* nest - ETHA_DEV_* */
+ ETHA_INFO_INFOMASK, /* u32 */
+ ETHA_INFO_COMPACT, /* flag */
+ ETHA_INFO_DRVINFO, /* nest - ETHA_DRVINFO_* */
+ ETHA_INFO_PERMADDR, /* nest - ETHA_PERMADDR_* */
+ ETHA_INFO_TSINFO, /* nest - ETHA_TSINFO_* */
+
+ __ETHA_INFO_CNT,
+ ETHA_INFO_MAX = (__ETHA_INFO_CNT - 1)
+};
+
+#define ETH_INFO_IM_DRVINFO 0x01
+
+#define ETH_INFO_IM_ALL 0x01
+
+enum {
+ ETHA_DRVINFO_UNSPEC,
+ ETHA_DRVINFO_DRIVER, /* string */
+ ETHA_DRVINFO_FWVERSION, /* string */
+ ETHA_DRVINFO_BUSINFO, /* string */
+ ETHA_DRVINFO_EROM_VER, /* string */
+
+ __ETHA_DRVINFO_CNT,
+ ETHA_DRVINFO_MAX = (__ETHA_DRVINFO_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 11ceb00821b3..96d41dc45d4f 100644
--- a/net/ethtool/Makefile
+++ b/net/ethtool/Makefile
@@ -4,4 +4,4 @@ obj-y += ioctl.o common.o

obj-$(CONFIG_ETHTOOL_NETLINK) += ethtool_nl.o

-ethtool_nl-y := netlink.o bitset.o strset.o
+ethtool_nl-y := netlink.o bitset.o strset.o info.o
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 73f721a1c557..e0bd7c6c5874 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -1,5 +1,7 @@
// SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note

+#include <linux/rtnetlink.h>
+#include <net/devlink.h>
#include "common.h"

const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
@@ -81,3 +83,55 @@ phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN] = {
[ETHTOOL_ID_UNSPEC] = "Unspec",
[ETHTOOL_PHY_DOWNSHIFT] = "phy-downshift",
};
+
+int __ethtool_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
+{
+ const struct ethtool_ops *ops = dev->ethtool_ops;
+
+ memset(info, 0, sizeof(*info));
+ info->cmd = ETHTOOL_GDRVINFO;
+ if (ops->get_drvinfo) {
+ ops->get_drvinfo(dev, info);
+ } else if (dev->dev.parent && dev->dev.parent->driver) {
+ strlcpy(info->bus_info, dev_name(dev->dev.parent),
+ sizeof(info->bus_info));
+ strlcpy(info->driver, dev->dev.parent->driver->name,
+ sizeof(info->driver));
+ } else {
+ return -EOPNOTSUPP;
+ }
+
+ /* this method of obtaining string set info is deprecated;
+ * Use ETHTOOL_GSSET_INFO instead.
+ */
+ if (ops->get_sset_count) {
+ int rc;
+
+ rc = ops->get_sset_count(dev, ETH_SS_TEST);
+ if (rc >= 0)
+ info->testinfo_len = rc;
+ rc = ops->get_sset_count(dev, ETH_SS_STATS);
+ if (rc >= 0)
+ info->n_stats = rc;
+ rc = ops->get_sset_count(dev, ETH_SS_PRIV_FLAGS);
+ if (rc >= 0)
+ info->n_priv_flags = rc;
+ }
+ if (ops->get_regs_len) {
+ int ret = ops->get_regs_len(dev);
+
+ if (ret > 0)
+ info->regdump_len = ret;
+ }
+
+ if (ops->get_eeprom_len)
+ info->eedump_len = ops->get_eeprom_len(dev);
+
+ rtnl_unlock();
+ if (!info->fw_version[0])
+ devlink_compat_running_version(dev, info->fw_version,
+ sizeof(info->fw_version));
+ rtnl_lock();
+
+ return 0;
+}
diff --git a/net/ethtool/common.h b/net/ethtool/common.h
index 41b2efc1e4e1..e87e58b3a274 100644
--- a/net/ethtool/common.h
+++ b/net/ethtool/common.h
@@ -3,6 +3,7 @@
#ifndef _ETHTOOL_COMMON_H
#define _ETHTOOL_COMMON_H

+#include <linux/netdevice.h>
#include <linux/ethtool.h>

extern const char
@@ -14,4 +15,5 @@ tunable_strings[__ETHTOOL_TUNABLE_COUNT][ETH_GSTRING_LEN];
extern const char
phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN];

+int __ethtool_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info);
#endif /* _ETHTOOL_COMMON_H */
diff --git a/net/ethtool/info.c b/net/ethtool/info.c
new file mode 100644
index 000000000000..1a2e78d238e3
--- /dev/null
+++ b/net/ethtool/info.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
+
+#include "netlink.h"
+#include "common.h"
+#include "bitset.h"
+
+struct info_data {
+ struct common_req_info reqinfo_base;
+
+ /* everything below here will be reset for each device in dumps */
+ struct common_reply_data repdata_base;
+ struct ethtool_drvinfo drvinfo;
+};
+
+static const struct nla_policy get_info_policy[ETHA_INFO_MAX + 1] = {
+ [ETHA_INFO_UNSPEC] = { .type = NLA_REJECT },
+ [ETHA_INFO_DEV] = { .type = NLA_NESTED },
+ [ETHA_INFO_INFOMASK] = { .type = NLA_U32 },
+ [ETHA_INFO_COMPACT] = { .type = NLA_FLAG },
+ [ETHA_INFO_DRVINFO] = { .type = NLA_REJECT },
+};
+
+static int parse_info(struct common_req_info *req_info, struct sk_buff *skb,
+ struct genl_info *info, const struct nlmsghdr *nlhdr)
+{
+ struct nlattr *tb[ETHA_INFO_MAX + 1];
+ int ret;
+
+ ret = genlmsg_parse(nlhdr, &ethtool_genl_family, tb, ETHA_INFO_MAX,
+ get_info_policy, info ? info->extack : NULL);
+ if (ret < 0)
+ return ret;
+
+ if (tb[ETHA_INFO_DEV]) {
+ req_info->dev = ethnl_dev_get(info, tb[ETHA_INFO_DEV]);
+ if (IS_ERR(req_info->dev)) {
+ ret = PTR_ERR(req_info->dev);
+ req_info->dev = NULL;
+ return ret;
+ }
+ }
+ if (tb[ETHA_INFO_INFOMASK])
+ req_info->req_mask = nla_get_u32(tb[ETHA_INFO_INFOMASK]);
+ if (tb[ETHA_INFO_COMPACT])
+ req_info->compact = true;
+ if (req_info->req_mask == 0)
+ req_info->req_mask = ETH_INFO_IM_ALL;
+
+ return 0;
+}
+
+static int prepare_info(struct common_req_info *req_info,
+ struct genl_info *info)
+{
+ struct info_data *data =
+ container_of(req_info, struct info_data, reqinfo_base);
+ struct net_device *dev = data->repdata_base.dev;
+ u32 req_mask = req_info->req_mask & ETH_INFO_IM_ALL;
+ int ret;
+
+ ret = ethnl_before_ops(dev);
+ if (ret < 0)
+ return ret;
+ if (req_mask & ETH_INFO_IM_DRVINFO) {
+ ret = __ethtool_get_drvinfo(dev, &data->drvinfo);
+ if (ret < 0)
+ req_mask &= ~ETH_INFO_IM_DRVINFO;
+ }
+ ethnl_after_ops(dev);
+
+ data->repdata_base.info_mask = req_mask;
+ if (req_info->req_mask & ~req_mask)
+ warn_partial_info(info);
+ return 0;
+}
+
+static int drvinfo_size(const struct ethtool_drvinfo *drvinfo)
+{
+ int len = 0;
+
+ len += ethnl_str_ifne_size(drvinfo->driver);
+ len += ethnl_str_ifne_size(drvinfo->fw_version);
+ len += ethnl_str_ifne_size(drvinfo->bus_info);
+ len += ethnl_str_ifne_size(drvinfo->erom_version);
+
+ return nla_total_size(len);
+}
+
+static int info_size(const struct common_req_info *req_info)
+{
+ const struct info_data *data =
+ container_of(req_info, struct info_data, reqinfo_base);
+ u32 info_mask = data->repdata_base.info_mask;
+ int len = 0;
+
+ len += dev_ident_size();
+ if (info_mask & ETH_INFO_IM_DRVINFO)
+ len += drvinfo_size(&data->drvinfo);
+
+ return len;
+}
+
+static int fill_drvinfo(struct sk_buff *skb,
+ const struct ethtool_drvinfo *drvinfo)
+{
+ struct nlattr *nest = ethnl_nest_start(skb, ETHA_INFO_DRVINFO);
+ int ret;
+
+ if (!nest)
+ return -EMSGSIZE;
+ ret = -EMSGSIZE;
+ if (ethnl_put_str_ifne(skb, ETHA_DRVINFO_DRIVER, drvinfo->driver) ||
+ ethnl_put_str_ifne(skb, ETHA_DRVINFO_FWVERSION,
+ drvinfo->fw_version) ||
+ ethnl_put_str_ifne(skb, ETHA_DRVINFO_BUSINFO, drvinfo->bus_info) ||
+ ethnl_put_str_ifne(skb, ETHA_DRVINFO_EROM_VER,
+ drvinfo->erom_version))
+ goto err;
+
+ nla_nest_end(skb, nest);
+ return 0;
+err:
+ nla_nest_cancel(skb, nest);
+ return ret;
+}
+
+static int fill_info(struct sk_buff *skb,
+ const struct common_req_info *req_info)
+{
+ const struct info_data *data =
+ container_of(req_info, struct info_data, reqinfo_base);
+ u32 info_mask = data->repdata_base.info_mask;
+ int ret;
+
+ if (info_mask & ETH_INFO_IM_DRVINFO) {
+ ret = fill_drvinfo(skb, &data->drvinfo);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+const struct get_request_ops info_request_ops = {
+ .request_cmd = ETHNL_CMD_GET_INFO,
+ .reply_cmd = ETHNL_CMD_SET_INFO,
+ .dev_attrtype = ETHA_INFO_DEV,
+ .data_size = sizeof(struct info_data),
+ .repdata_offset = offsetof(struct info_data, repdata_base),
+
+ .parse_request = parse_info,
+ .prepare_data = prepare_info,
+ .reply_size = info_size,
+ .fill_reply = fill_info,
+};
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 71a1643adb2b..c883239001a4 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -685,56 +685,14 @@ static noinline_for_stack int ethtool_get_drvinfo(struct net_device *dev,
void __user *useraddr)
{
struct ethtool_drvinfo info;
- const struct ethtool_ops *ops = dev->ethtool_ops;
-
- memset(&info, 0, sizeof(info));
- info.cmd = ETHTOOL_GDRVINFO;
- if (ops->get_drvinfo) {
- ops->get_drvinfo(dev, &info);
- } else if (dev->dev.parent && dev->dev.parent->driver) {
- strlcpy(info.bus_info, dev_name(dev->dev.parent),
- sizeof(info.bus_info));
- strlcpy(info.driver, dev->dev.parent->driver->name,
- sizeof(info.driver));
- } else {
- return -EOPNOTSUPP;
- }
-
- /*
- * this method of obtaining string set info is deprecated;
- * Use ETHTOOL_GSSET_INFO instead.
- */
- if (ops->get_sset_count) {
- int rc;
-
- rc = ops->get_sset_count(dev, ETH_SS_TEST);
- if (rc >= 0)
- info.testinfo_len = rc;
- rc = ops->get_sset_count(dev, ETH_SS_STATS);
- if (rc >= 0)
- info.n_stats = rc;
- rc = ops->get_sset_count(dev, ETH_SS_PRIV_FLAGS);
- if (rc >= 0)
- info.n_priv_flags = rc;
- }
- if (ops->get_regs_len) {
- int ret = ops->get_regs_len(dev);
-
- if (ret > 0)
- info.regdump_len = ret;
- }
-
- if (ops->get_eeprom_len)
- info.eedump_len = ops->get_eeprom_len(dev);
-
- rtnl_unlock();
- if (!info.fw_version[0])
- devlink_compat_running_version(dev, info.fw_version,
- sizeof(info.fw_version));
- rtnl_lock();
+ int rc;

+ rc = __ethtool_get_drvinfo(dev, &info);
+ if (rc < 0)
+ return rc;
if (copy_to_user(useraddr, &info, sizeof(info)))
return -EFAULT;
+
return 0;
}

diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 082a9f2aa0a7..e27dec427414 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -87,9 +87,11 @@ int ethnl_fill_dev(struct sk_buff *msg, struct net_device *dev, u16 attrtype)
/* GET request helpers */

extern const struct get_request_ops strset_request_ops;
+extern const struct get_request_ops info_request_ops;

const struct get_request_ops *get_requests[__ETHNL_CMD_CNT] = {
[ETHNL_CMD_GET_STRSET] = &strset_request_ops,
+ [ETHNL_CMD_GET_INFO] = &info_request_ops,
};

static struct common_req_info *alloc_get_data(const struct get_request_ops *ops)
@@ -508,6 +510,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
.dumpit = ethnl_get_dumpit,
.done = ethnl_get_done,
},
+ {
+ .cmd = ETHNL_CMD_GET_INFO,
+ .doit = ethnl_get_doit,
+ .start = ethnl_get_start,
+ .dumpit = ethnl_get_dumpit,
+ .done = ethnl_get_done,
+ },
};

static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
--
2.20.1