ethtool: provide ring sizes with RINGS_GET request

Implement RINGS_GET request to get ring sizes of a network device. These
are traditionally available via ETHTOOL_GRINGPARAM ioctl request.

Omit attributes for ring types which are not supported by driver or device
(zero reported for maximum).

v2: (all suggested by Jakub Kicinski)
  - minor cleanup in rings_prepare_data()
  - more descriptive rings_reply_size()
  - omit attributes with zero max size

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index e553112..798c2f9 100644 (file)
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -193,6 +193,7 @@ Userspace to kernel:
   ``ETHTOOL_MSG_FEATURES_SET``          set device features
   ``ETHTOOL_MSG_PRIVFLAGS_GET``         get private flags
   ``ETHTOOL_MSG_PRIVFLAGS_SET``         set private flags
+  ``ETHTOOL_MSG_RINGS_GET``             get ring sizes
   ===================================== ================================
 
 Kernel to userspace:
@@ -213,6 +214,7 @@ Kernel to userspace:
   ``ETHTOOL_MSG_FEATURES_NTF``          netdev features notification
   ``ETHTOOL_MSG_PRIVFLAGS_GET_REPLY``   private flags
   ``ETHTOOL_MSG_PRIVFLAGS_NTF``         private flags
+  ``ETHTOOL_MSG_RINGS_GET_REPLY``       ring sizes
   ===================================== =================================
 
 ``GET`` requests are sent by userspace applications to retrieve device
@@ -645,6 +647,32 @@ Request contents:
 modify only values of some of them.
 
 
+RINGS_GET
+=========
+
+Gets ring sizes like ``ETHTOOL_GRINGPARAM`` ioctl request.
+
+Request contents:
+
+  ====================================  ======  ==========================
+  ``ETHTOOL_A_RINGS_HEADER``            nested  request header
+  ====================================  ======  ==========================
+
+Kernel response contents:
+
+  ====================================  ======  ==========================
+  ``ETHTOOL_A_RINGS_HEADER``            nested  reply header
+  ``ETHTOOL_A_RINGS_RX_MAX``            u32     max size of RX ring
+  ``ETHTOOL_A_RINGS_RX_MINI_MAX``       u32     max size of RX mini ring
+  ``ETHTOOL_A_RINGS_RX_JUMBO_MAX``      u32     max size of RX jumbo ring
+  ``ETHTOOL_A_RINGS_TX_MAX``            u32     max size of TX ring
+  ``ETHTOOL_A_RINGS_RX``                u32     size of RX ring
+  ``ETHTOOL_A_RINGS_RX_MINI``           u32     size of RX mini ring
+  ``ETHTOOL_A_RINGS_RX_JUMBO``          u32     size of RX jumbo ring
+  ``ETHTOOL_A_RINGS_TX``                u32     size of TX ring
+  ====================================  ======  ==========================
+
+
 Request translation
 ===================
 
@@ -671,7 +699,7 @@ have their netlink replacement yet.
   ``ETHTOOL_SEEPROM``                 n/a
   ``ETHTOOL_GCOALESCE``               n/a
   ``ETHTOOL_SCOALESCE``               n/a
-  ``ETHTOOL_GRINGPARAM``              n/a
+  ``ETHTOOL_GRINGPARAM``              ``ETHTOOL_MSG_RINGS_GET``
   ``ETHTOOL_SRINGPARAM``              n/a
   ``ETHTOOL_GPAUSEPARAM``             n/a
   ``ETHTOOL_SPAUSEPARAM``             n/a

diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 7f23a7f..7cd220f 100644 (file)
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -28,6 +28,7 @@ enum {
        ETHTOOL_MSG_FEATURES_SET,
        ETHTOOL_MSG_PRIVFLAGS_GET,
        ETHTOOL_MSG_PRIVFLAGS_SET,
+       ETHTOOL_MSG_RINGS_GET,
 
        /* add new constants above here */
        __ETHTOOL_MSG_USER_CNT,
@@ -52,6 +53,7 @@ enum {
        ETHTOOL_MSG_FEATURES_NTF,
        ETHTOOL_MSG_PRIVFLAGS_GET_REPLY,
        ETHTOOL_MSG_PRIVFLAGS_NTF,
+       ETHTOOL_MSG_RINGS_GET_REPLY,
 
        /* add new constants above here */
        __ETHTOOL_MSG_KERNEL_CNT,
@@ -264,6 +266,25 @@ enum {
        ETHTOOL_A_PRIVFLAGS_MAX = __ETHTOOL_A_PRIVFLAGS_CNT - 1
 };
 
+/* RINGS */
+
+enum {
+       ETHTOOL_A_RINGS_UNSPEC,
+       ETHTOOL_A_RINGS_HEADER,                         /* nest - _A_HEADER_* */
+       ETHTOOL_A_RINGS_RX_MAX,                         /* u32 */
+       ETHTOOL_A_RINGS_RX_MINI_MAX,                    /* u32 */
+       ETHTOOL_A_RINGS_RX_JUMBO_MAX,                   /* u32 */
+       ETHTOOL_A_RINGS_TX_MAX,                         /* u32 */
+       ETHTOOL_A_RINGS_RX,                             /* u32 */
+       ETHTOOL_A_RINGS_RX_MINI,                        /* u32 */
+       ETHTOOL_A_RINGS_RX_JUMBO,                       /* u32 */
+       ETHTOOL_A_RINGS_TX,                             /* u32 */
+
+       /* add new constants above here */
+       __ETHTOOL_A_RINGS_CNT,
+       ETHTOOL_A_RINGS_MAX = (__ETHTOOL_A_RINGS_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 58708bc..b48b70e 100644 (file)
--- 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 debug.o wol.o features.o privflags.o
+                  linkstate.o debug.o wol.o features.o privflags.o rings.o

diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index dec82b0..0dc25a4 100644 (file)
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -217,6 +217,7 @@ ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {
        [ETHTOOL_MSG_WOL_GET]           = &ethnl_wol_request_ops,
        [ETHTOOL_MSG_FEATURES_GET]      = &ethnl_features_request_ops,
        [ETHTOOL_MSG_PRIVFLAGS_GET]     = &ethnl_privflags_request_ops,
+       [ETHTOOL_MSG_RINGS_GET]         = &ethnl_rings_request_ops,
 };
 
 static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb)
@@ -748,6 +749,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
                .flags  = GENL_UNS_ADMIN_PERM,
                .doit   = ethnl_set_privflags,
        },
+       {
+               .cmd    = ETHTOOL_MSG_RINGS_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 ca789f5..0176193 100644 (file)
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -339,6 +339,7 @@ extern const struct ethnl_request_ops ethnl_debug_request_ops;
 extern const struct ethnl_request_ops ethnl_wol_request_ops;
 extern const struct ethnl_request_ops ethnl_features_request_ops;
 extern const struct ethnl_request_ops ethnl_privflags_request_ops;
+extern const struct ethnl_request_ops ethnl_rings_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/rings.c b/net/ethtool/rings.c
new file mode 100644 (file)
index 0000000..d3129d8
--- /dev/null
+++ b/net/ethtool/rings.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "netlink.h"
+#include "common.h"
+
+struct rings_req_info {
+       struct ethnl_req_info           base;
+};
+
+struct rings_reply_data {
+       struct ethnl_reply_data         base;
+       struct ethtool_ringparam        ringparam;
+};
+
+#define RINGS_REPDATA(__reply_base) \
+       container_of(__reply_base, struct rings_reply_data, base)
+
+static const struct nla_policy
+rings_get_policy[ETHTOOL_A_RINGS_MAX + 1] = {
+       [ETHTOOL_A_RINGS_UNSPEC]                = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_HEADER]                = { .type = NLA_NESTED },
+       [ETHTOOL_A_RINGS_RX_MAX]                = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_RX_MINI_MAX]           = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_RX_JUMBO_MAX]          = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_TX_MAX]                = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_RX]                    = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_RX_MINI]               = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_RX_JUMBO]              = { .type = NLA_REJECT },
+       [ETHTOOL_A_RINGS_TX]                    = { .type = NLA_REJECT },
+};
+
+static int rings_prepare_data(const struct ethnl_req_info *req_base,
+                             struct ethnl_reply_data *reply_base,
+                             struct genl_info *info)
+{
+       struct rings_reply_data *data = RINGS_REPDATA(reply_base);
+       struct net_device *dev = reply_base->dev;
+       int ret;
+
+       if (!dev->ethtool_ops->get_ringparam)
+               return -EOPNOTSUPP;
+       ret = ethnl_ops_begin(dev);
+       if (ret < 0)
+               return ret;
+       dev->ethtool_ops->get_ringparam(dev, &data->ringparam);
+       ethnl_ops_complete(dev);
+
+       return 0;
+}
+
+static int rings_reply_size(const struct ethnl_req_info *req_base,
+                           const struct ethnl_reply_data *reply_base)
+{
+       return nla_total_size(sizeof(u32)) +    /* _RINGS_RX_MAX */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_RX_MINI_MAX */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_RX_JUMBO_MAX */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_TX_MAX */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_RX */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_RX_MINI */
+              nla_total_size(sizeof(u32)) +    /* _RINGS_RX_JUMBO */
+              nla_total_size(sizeof(u32));     /* _RINGS_TX */
+}
+
+static int rings_fill_reply(struct sk_buff *skb,
+                           const struct ethnl_req_info *req_base,
+                           const struct ethnl_reply_data *reply_base)
+{
+       const struct rings_reply_data *data = RINGS_REPDATA(reply_base);
+       const struct ethtool_ringparam *ringparam = &data->ringparam;
+
+       if ((ringparam->rx_max_pending &&
+            (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MAX,
+                         ringparam->rx_max_pending) ||
+             nla_put_u32(skb, ETHTOOL_A_RINGS_RX,
+                         ringparam->rx_pending))) ||
+           (ringparam->rx_mini_max_pending &&
+            (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MINI_MAX,
+                         ringparam->rx_mini_max_pending) ||
+             nla_put_u32(skb, ETHTOOL_A_RINGS_RX_MINI,
+                         ringparam->rx_mini_pending))) ||
+           (ringparam->rx_jumbo_max_pending &&
+            (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_JUMBO_MAX,
+                         ringparam->rx_jumbo_max_pending) ||
+             nla_put_u32(skb, ETHTOOL_A_RINGS_RX_JUMBO,
+                         ringparam->rx_jumbo_pending))) ||
+           (ringparam->tx_max_pending &&
+            (nla_put_u32(skb, ETHTOOL_A_RINGS_TX_MAX,
+                         ringparam->tx_max_pending) ||
+             nla_put_u32(skb, ETHTOOL_A_RINGS_TX,
+                         ringparam->tx_pending))))
+               return -EMSGSIZE;
+
+       return 0;
+}
+
+const struct ethnl_request_ops ethnl_rings_request_ops = {
+       .request_cmd            = ETHTOOL_MSG_RINGS_GET,
+       .reply_cmd              = ETHTOOL_MSG_RINGS_GET_REPLY,
+       .hdr_attr               = ETHTOOL_A_RINGS_HEADER,
+       .max_attr               = ETHTOOL_A_RINGS_MAX,
+       .req_info_size          = sizeof(struct rings_req_info),
+       .reply_data_size        = sizeof(struct rings_reply_data),
+       .request_policy         = rings_get_policy,
+
+       .prepare_data           = rings_prepare_data,
+       .reply_size             = rings_reply_size,
+       .fill_reply             = rings_fill_reply,
+};