From 3d2b847fb99cf2b28aa046e486636e555bc6ed1c Mon Sep 17 00:00:00 2001 From: Michal Kubecek Date: Fri, 27 Dec 2019 15:56:23 +0100 Subject: [PATCH] ethtool: provide link state with LINKSTATE_GET request Implement LINKSTATE_GET netlink request to get link state information. At the moment, only link up flag as provided by ETHTOOL_GLINK ioctl command is returned. LINKSTATE_GET request can be used with NLM_F_DUMP (without device identification) to request the information for all devices in current network namespace providing the data. Signed-off-by: Michal Kubecek Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- Documentation/networking/ethtool-netlink.rst | 33 ++++++++- include/uapi/linux/ethtool_netlink.h | 14 ++++ net/ethtool/Makefile | 3 +- net/ethtool/common.c | 8 +++ net/ethtool/common.h | 3 + net/ethtool/ioctl.c | 8 +-- net/ethtool/linkstate.c | 74 ++++++++++++++++++++ net/ethtool/netlink.c | 8 +++ net/ethtool/netlink.h | 1 + 9 files changed, 146 insertions(+), 6 deletions(-) create mode 100644 net/ethtool/linkstate.c diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst index 9d96d51e9360..c60afba69e3c 100644 --- a/Documentation/networking/ethtool-netlink.rst +++ b/Documentation/networking/ethtool-netlink.rst @@ -184,6 +184,7 @@ Userspace to kernel: ``ETHTOOL_MSG_LINKINFO_SET`` set link settings ``ETHTOOL_MSG_LINKMODES_GET`` get link modes info ``ETHTOOL_MSG_LINKMODES_SET`` set link modes info + ``ETHTOOL_MSG_LINKSTATE_GET`` get link state ===================================== ================================ Kernel to userspace: @@ -194,6 +195,7 @@ Kernel to userspace: ``ETHTOOL_MSG_LINKINFO_NTF`` link settings notification ``ETHTOOL_MSG_LINKMODES_GET_REPLY`` link modes info ``ETHTOOL_MSG_LINKMODES_NTF`` link modes notification + ``ETHTOOL_MSG_LINKSTATE_GET_REPLY`` link state info ===================================== ================================ ``GET`` requests are sent by userspace applications to retrieve device @@ -392,6 +394,35 @@ is supposed to allow requesting changes without knowing what exactly kernel supports. +LINKSTATE_GET +============= + +Requests link state information. At the moment, only link up/down flag (as +provided by ``ETHTOOL_GLINK`` ioctl command) is provided but some future +extensions are planned (e.g. link down reason). This request does not have any +attributes. + +Request contents: + + ==================================== ====== ========================== + ``ETHTOOL_A_LINKSTATE_HEADER`` nested request header + ==================================== ====== ========================== + +Kernel response contents: + + ==================================== ====== ========================== + ``ETHTOOL_A_LINKSTATE_HEADER`` nested reply header + ``ETHTOOL_A_LINKSTATE_LINK`` bool link state (up/down) + ==================================== ====== ========================== + +For most NIC drivers, the value of ``ETHTOOL_A_LINKSTATE_LINK`` returns +carrier flag provided by ``netif_carrier_ok()`` but there are drivers which +define their own handler. + +``LINKSTATE_GET`` allows dump requests (kernel returns reply messages for all +devices supporting the request). + + Request translation =================== @@ -413,7 +444,7 @@ have their netlink replacement yet. ``ETHTOOL_GMSGLVL`` n/a ``ETHTOOL_SMSGLVL`` n/a ``ETHTOOL_NWAY_RST`` n/a - ``ETHTOOL_GLINK`` n/a + ``ETHTOOL_GLINK`` ``ETHTOOL_MSG_LINKSTATE_GET`` ``ETHTOOL_GEEPROM`` n/a ``ETHTOOL_SEEPROM`` n/a ``ETHTOOL_GCOALESCE`` n/a diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h index 35948df6d6e3..02f82f42a889 100644 --- a/include/uapi/linux/ethtool_netlink.h +++ b/include/uapi/linux/ethtool_netlink.h @@ -19,6 +19,7 @@ enum { ETHTOOL_MSG_LINKINFO_SET, ETHTOOL_MSG_LINKMODES_GET, ETHTOOL_MSG_LINKMODES_SET, + ETHTOOL_MSG_LINKSTATE_GET, /* add new constants above here */ __ETHTOOL_MSG_USER_CNT, @@ -33,6 +34,7 @@ enum { ETHTOOL_MSG_LINKINFO_NTF, ETHTOOL_MSG_LINKMODES_GET_REPLY, ETHTOOL_MSG_LINKMODES_NTF, + ETHTOOL_MSG_LINKSTATE_GET_REPLY, /* add new constants above here */ __ETHTOOL_MSG_KERNEL_CNT, @@ -181,6 +183,18 @@ enum { ETHTOOL_A_LINKMODES_MAX = __ETHTOOL_A_LINKMODES_CNT - 1 }; +/* LINKSTATE */ + +enum { + ETHTOOL_A_LINKSTATE_UNSPEC, + ETHTOOL_A_LINKSTATE_HEADER, /* nest - _A_HEADER_* */ + ETHTOOL_A_LINKSTATE_LINK, /* u8 */ + + /* add new constants above here */ + __ETHTOOL_A_LINKSTATE_CNT, + ETHTOOL_A_LINKSTATE_MAX = __ETHTOOL_A_LINKSTATE_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 8023da6672ce..9a1332fb0cc6 100644 --- a/net/ethtool/Makefile +++ b/net/ethtool/Makefile @@ -4,4 +4,5 @@ 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 +ethtool_nl-y := netlink.o bitset.o strset.o linkinfo.o linkmodes.o \ + linkstate.o diff --git a/net/ethtool/common.c b/net/ethtool/common.c index 1d4a0aeff2cb..e621b1694d2f 100644 --- a/net/ethtool/common.c +++ b/net/ethtool/common.c @@ -217,3 +217,11 @@ convert_legacy_settings_to_link_ksettings( = legacy_settings->eth_tp_mdix_ctrl; return retval; } + +int __ethtool_get_link(struct net_device *dev) +{ + if (!dev->ethtool_ops->get_link) + return -EOPNOTSUPP; + + return netif_running(dev) && dev->ethtool_ops->get_link(dev); +} diff --git a/net/ethtool/common.h b/net/ethtool/common.h index c8a237402729..5c5f7dc90cd4 100644 --- a/net/ethtool/common.h +++ b/net/ethtool/common.h @@ -3,6 +3,7 @@ #ifndef _ETHTOOL_COMMON_H #define _ETHTOOL_COMMON_H +#include #include /* compose link mode index from speed, type and duplex */ @@ -19,6 +20,8 @@ extern const char phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN]; extern const char link_mode_names[][ETH_GSTRING_LEN]; +int __ethtool_get_link(struct net_device *dev); + bool convert_legacy_settings_to_link_ksettings( struct ethtool_link_ksettings *link_ksettings, const struct ethtool_cmd *legacy_settings); diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index 36e2ef2d900d..182bffbffa78 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -1365,12 +1365,12 @@ static int ethtool_nway_reset(struct net_device *dev) static int ethtool_get_link(struct net_device *dev, char __user *useraddr) { struct ethtool_value edata = { .cmd = ETHTOOL_GLINK }; + int link = __ethtool_get_link(dev); - if (!dev->ethtool_ops->get_link) - return -EOPNOTSUPP; - - edata.data = netif_running(dev) && dev->ethtool_ops->get_link(dev); + if (link < 0) + return link; + edata.data = link; if (copy_to_user(useraddr, &edata, sizeof(edata))) return -EFAULT; return 0; diff --git a/net/ethtool/linkstate.c b/net/ethtool/linkstate.c new file mode 100644 index 000000000000..2740cde0a182 --- /dev/null +++ b/net/ethtool/linkstate.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include "netlink.h" +#include "common.h" + +struct linkstate_req_info { + struct ethnl_req_info base; +}; + +struct linkstate_reply_data { + struct ethnl_reply_data base; + int link; +}; + +#define LINKSTATE_REPDATA(__reply_base) \ + container_of(__reply_base, struct linkstate_reply_data, base) + +static const struct nla_policy +linkstate_get_policy[ETHTOOL_A_LINKSTATE_MAX + 1] = { + [ETHTOOL_A_LINKSTATE_UNSPEC] = { .type = NLA_REJECT }, + [ETHTOOL_A_LINKSTATE_HEADER] = { .type = NLA_NESTED }, + [ETHTOOL_A_LINKSTATE_LINK] = { .type = NLA_REJECT }, +}; + +static int linkstate_prepare_data(const struct ethnl_req_info *req_base, + struct ethnl_reply_data *reply_base, + struct genl_info *info) +{ + struct linkstate_reply_data *data = LINKSTATE_REPDATA(reply_base); + struct net_device *dev = reply_base->dev; + int ret; + + ret = ethnl_ops_begin(dev); + if (ret < 0) + return ret; + data->link = __ethtool_get_link(dev); + ethnl_ops_complete(dev); + + return 0; +} + +static int linkstate_reply_size(const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + return nla_total_size(sizeof(u8)) /* LINKSTATE_LINK */ + + 0; +} + +static int linkstate_fill_reply(struct sk_buff *skb, + const struct ethnl_req_info *req_base, + const struct ethnl_reply_data *reply_base) +{ + struct linkstate_reply_data *data = LINKSTATE_REPDATA(reply_base); + + if (data->link >= 0 && + nla_put_u8(skb, ETHTOOL_A_LINKSTATE_LINK, !!data->link)) + return -EMSGSIZE; + + return 0; +} + +const struct ethnl_request_ops ethnl_linkstate_request_ops = { + .request_cmd = ETHTOOL_MSG_LINKSTATE_GET, + .reply_cmd = ETHTOOL_MSG_LINKSTATE_GET_REPLY, + .hdr_attr = ETHTOOL_A_LINKSTATE_HEADER, + .max_attr = ETHTOOL_A_LINKSTATE_MAX, + .req_info_size = sizeof(struct linkstate_req_info), + .reply_data_size = sizeof(struct linkstate_reply_data), + .request_policy = linkstate_get_policy, + + .prepare_data = linkstate_prepare_data, + .reply_size = linkstate_reply_size, + .fill_reply = linkstate_fill_reply, +}; diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c index 1b5e1bd26504..4ca96c7b86b3 100644 --- a/net/ethtool/netlink.c +++ b/net/ethtool/netlink.c @@ -210,6 +210,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = { [ETHTOOL_MSG_STRSET_GET] = ðnl_strset_request_ops, [ETHTOOL_MSG_LINKINFO_GET] = ðnl_linkinfo_request_ops, [ETHTOOL_MSG_LINKMODES_GET] = ðnl_linkmodes_request_ops, + [ETHTOOL_MSG_LINKSTATE_GET] = ðnl_linkstate_request_ops, }; static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb) @@ -645,6 +646,13 @@ static const struct genl_ops ethtool_genl_ops[] = { .flags = GENL_UNS_ADMIN_PERM, .doit = ethnl_set_linkmodes, }, + { + .cmd = ETHTOOL_MSG_LINKSTATE_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 1269cca8a002..da9d6521a4eb 100644 --- a/net/ethtool/netlink.h +++ b/net/ethtool/netlink.h @@ -333,6 +333,7 @@ struct ethnl_request_ops { 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; int ethnl_set_linkinfo(struct sk_buff *skb, struct genl_info *info); int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info);