On 12/19, Lorenzo Bianconi wrote:
From: Marek Majtyka <alardam@xxxxxxxxx>
Implement support for checking what kind of XDP features a netdev
supports. Previously, there was no way to do this other than to try to
create an AF_XDP socket on the interface or load an XDP program and see
if it worked. This commit changes this by adding a new variable which
describes all xdp supported functions on pretty detailed level:
- aborted
- drop
- pass
- tx
- redirect
- sock_zerocopy
- hw_offload
- redirect_target
- tx_lock
- frag_rx
- frag_target
Zerocopy mode requires that redirect XDP operation is implemented in a
driver and the driver supports also zero copy mode. Full mode requires
that all XDP operation are implemented in the driver. Basic mode is just
full mode without redirect operation. Frag target requires
redirect_target one is supported by the driver.
Can you share more about _why_ is it needed? If we can already obtain
most of these signals via probing, why export the flags?
Initially, these new flags are disabled for all drivers by default.
Co-developed-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
Co-developed-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Marek Majtyka <alardam@xxxxxxxxx>
---
.../networking/netdev-xdp-features.rst | 60 +++++++++++++++++
include/linux/netdevice.h | 2 +
include/linux/xdp_features.h | 64 +++++++++++++++++++
include/uapi/linux/if_link.h | 7 ++
include/uapi/linux/xdp_features.h | 34 ++++++++++
net/core/rtnetlink.c | 34 ++++++++++
tools/include/uapi/linux/if_link.h | 7 ++
tools/include/uapi/linux/xdp_features.h | 34 ++++++++++
8 files changed, 242 insertions(+)
create mode 100644 Documentation/networking/netdev-xdp-features.rst
create mode 100644 include/linux/xdp_features.h
create mode 100644 include/uapi/linux/xdp_features.h
create mode 100644 tools/include/uapi/linux/xdp_features.h
diff --git a/Documentation/networking/netdev-xdp-features.rst
b/Documentation/networking/netdev-xdp-features.rst
new file mode 100644
index 000000000000..1dc803fe72dd
--- /dev/null
+++ b/Documentation/networking/netdev-xdp-features.rst
@@ -0,0 +1,60 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=====================
+Netdev XDP features
+=====================
+
+ * XDP FEATURES FLAGS
+
+Following netdev xdp features flags can be retrieved over route netlink
+interface (compact form) - the same way as netdev feature flags.
+These features flags are read only and cannot be change at runtime.
+
+* XDP_ABORTED
+
+This feature informs if netdev supports xdp aborted action.
+
+* XDP_DROP
+
+This feature informs if netdev supports xdp drop action.
+
+* XDP_PASS
+
+This feature informs if netdev supports xdp pass action.
+
+* XDP_TX
+
+This feature informs if netdev supports xdp tx action.
+
+* XDP_REDIRECT
+
+This feature informs if netdev supports xdp redirect action.
+It assumes the all beforehand mentioned flags are enabled.
+
+* XDP_SOCK_ZEROCOPY
+
+This feature informs if netdev driver supports xdp zero copy.
+It assumes the all beforehand mentioned flags are enabled.
+
+* XDP_HW_OFFLOAD
+
+This feature informs if netdev driver supports xdp hw oflloading.
+
+* XDP_TX_LOCK
+
+This feature informs if netdev ndo_xdp_xmit function requires locking.
+
+* XDP_REDIRECT_TARGET
+
+This feature informs if netdev implements ndo_xdp_xmit callback.
+
+* XDP_FRAG_RX
+
+This feature informs if netdev implements non-linear xdp buff support in
+the driver napi callback.
+
+* XDP_FRAG_TARGET
+
+This feature informs if netdev implements non-linear xdp buff support in
+ndo_xdp_xmit callback. XDP_FRAG_TARGET requires XDP_REDIRECT_TARGET is
properly
+supported.
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index aad12a179e54..ae5a8564383b 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -43,6 +43,7 @@
#include <net/xdp.h>
#include <linux/netdev_features.h>
+#include <linux/xdp_features.h>
#include <linux/neighbour.h>
#include <uapi/linux/netdevice.h>
#include <uapi/linux/if_bonding.h>
@@ -2362,6 +2363,7 @@ struct net_device {
struct rtnl_hw_stats64 *offload_xstats_l3;
struct devlink_port *devlink_port;
+ xdp_features_t xdp_features;
};
#define to_net_dev(d) container_of(d, struct net_device, dev)
diff --git a/include/linux/xdp_features.h b/include/linux/xdp_features.h
new file mode 100644
index 000000000000..4e72a86ef329
--- /dev/null
+++ b/include/linux/xdp_features.h
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Network device xdp features.
+ */
+#ifndef _LINUX_XDP_FEATURES_H
+#define _LINUX_XDP_FEATURES_H
+
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <asm/byteorder.h>
+#include <uapi/linux/xdp_features.h>
+
+typedef u32 xdp_features_t;
+
+#define __XDP_F_BIT(bit) ((xdp_features_t)1 << (bit))
+#define __XDP_F(name) __XDP_F_BIT(XDP_F_##name##_BIT)
+
+#define XDP_F_ABORTED __XDP_F(ABORTED)
+#define XDP_F_DROP __XDP_F(DROP)
+#define XDP_F_PASS __XDP_F(PASS)
+#define XDP_F_TX __XDP_F(TX)
+#define XDP_F_REDIRECT __XDP_F(REDIRECT)
+#define XDP_F_REDIRECT_TARGET __XDP_F(REDIRECT_TARGET)
+#define XDP_F_SOCK_ZEROCOPY __XDP_F(SOCK_ZEROCOPY)
+#define XDP_F_HW_OFFLOAD __XDP_F(HW_OFFLOAD)
+#define XDP_F_TX_LOCK __XDP_F(TX_LOCK)
+#define XDP_F_FRAG_RX __XDP_F(FRAG_RX)
+#define XDP_F_FRAG_TARGET __XDP_F(FRAG_TARGET)
+
+#define XDP_F_BASIC (XDP_F_ABORTED | XDP_F_DROP | \
+ XDP_F_PASS | XDP_F_TX)
+
+#define XDP_F_FULL (XDP_F_BASIC | XDP_F_REDIRECT)
+
+#define XDP_F_FULL_ZC (XDP_F_FULL | XDP_F_SOCK_ZEROCOPY)
+
+#define XDP_FEATURES_ABORTED_STR "xdp-aborted"
+#define XDP_FEATURES_DROP_STR "xdp-drop"
+#define XDP_FEATURES_PASS_STR "xdp-pass"
+#define XDP_FEATURES_TX_STR "xdp-tx"
+#define XDP_FEATURES_REDIRECT_STR "xdp-redirect"
+#define XDP_FEATURES_REDIRECT_TARGET_STR "xdp-redirect-target"
+#define XDP_FEATURES_SOCK_ZEROCOPY_STR "xdp-sock-zerocopy"
+#define XDP_FEATURES_HW_OFFLOAD_STR "xdp-hw-offload"
+#define XDP_FEATURES_TX_LOCK_STR "xdp-tx-lock"
+#define XDP_FEATURES_FRAG_RX_STR "xdp-frag-rx"
+#define XDP_FEATURES_FRAG_TARGET_STR "xdp-frag-target"
+
+#define DECLARE_XDP_FEATURES_TABLE(name, length) \
+ const char name[][length] = { \
+ [XDP_F_ABORTED_BIT] = XDP_FEATURES_ABORTED_STR, \
+ [XDP_F_DROP_BIT] = XDP_FEATURES_DROP_STR, \
+ [XDP_F_PASS_BIT] = XDP_FEATURES_PASS_STR, \
+ [XDP_F_TX_BIT] = XDP_FEATURES_TX_STR, \
+ [XDP_F_REDIRECT_BIT] = XDP_FEATURES_REDIRECT_STR, \
+ [XDP_F_REDIRECT_TARGET_BIT] = XDP_FEATURES_REDIRECT_TARGET_STR, \
+ [XDP_F_SOCK_ZEROCOPY_BIT] = XDP_FEATURES_SOCK_ZEROCOPY_STR, \
+ [XDP_F_HW_OFFLOAD_BIT] = XDP_FEATURES_HW_OFFLOAD_STR, \
+ [XDP_F_TX_LOCK_BIT] = XDP_FEATURES_TX_LOCK_STR, \
+ [XDP_F_FRAG_RX_BIT] = XDP_FEATURES_FRAG_RX_STR, \
+ [XDP_F_FRAG_TARGET_BIT] = XDP_FEATURES_FRAG_TARGET_STR, \
+ }
+
+#endif /* _LINUX_XDP_FEATURES_H */
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 1021a7e47a86..971c658ceaea 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -374,6 +374,8 @@ enum {
IFLA_DEVLINK_PORT,
+ IFLA_XDP_FEATURES,
+
__IFLA_MAX
};
@@ -1318,6 +1320,11 @@ enum {
#define IFLA_XDP_MAX (__IFLA_XDP_MAX - 1)
+enum {
+ IFLA_XDP_FEATURES_WORD_UNSPEC = 0,
+ IFLA_XDP_FEATURES_BITS_WORD,
+};
+
enum {
IFLA_EVENT_NONE,
IFLA_EVENT_REBOOT, /* internal reset / reboot */
diff --git a/include/uapi/linux/xdp_features.h
b/include/uapi/linux/xdp_features.h
new file mode 100644
index 000000000000..48eb42069bcd
--- /dev/null
+++ b/include/uapi/linux/xdp_features.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2020 Intel
+ */
+
+#ifndef __UAPI_LINUX_XDP_FEATURES__
+#define __UAPI_LINUX_XDP_FEATURES__
+
+enum {
+ XDP_F_ABORTED_BIT,
+ XDP_F_DROP_BIT,
+ XDP_F_PASS_BIT,
+ XDP_F_TX_BIT,
+ XDP_F_REDIRECT_BIT,
+ XDP_F_REDIRECT_TARGET_BIT,
+ XDP_F_SOCK_ZEROCOPY_BIT,
+ XDP_F_HW_OFFLOAD_BIT,
+ XDP_F_TX_LOCK_BIT,
+ XDP_F_FRAG_RX_BIT,
+ XDP_F_FRAG_TARGET_BIT,
+ /*
+ * Add your fresh new property above and remember to update
+ * documentation.
+ */
+ XDP_FEATURES_COUNT,
+};
+
+#define XDP_FEATURES_WORDS ((XDP_FEATURES_COUNT + 32 - 1) / 32)
+#define XDP_FEATURES_WORD(blocks, index) ((blocks)[(index) / 32U])
+#define XDP_FEATURES_FIELD_FLAG(index) (1U << (index) % 32U)
+#define XDP_FEATURES_BIT_IS_SET(blocks, index) \
+ (XDP_FEATURES_WORD(blocks, index) & XDP_FEATURES_FIELD_FLAG(index))
+
+#endif /* __UAPI_LINUX_XDP_FEATURES__ */
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 64289bc98887..1c299746b614 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1016,6 +1016,14 @@ static size_t rtnl_xdp_size(void)
return xdp_size;
}
+static size_t rtnl_xdp_features_size(void)
+{
+ size_t xdp_size = nla_total_size(0) + /* nest IFLA_XDP_FEATURES */
+ XDP_FEATURES_WORDS * nla_total_size(4);
+
+ return xdp_size;
+}
+
static size_t rtnl_prop_list_size(const struct net_device *dev)
{
struct netdev_name_node *name_node;
@@ -1103,6 +1111,7 @@ static noinline size_t if_nlmsg_size(const struct
net_device *dev,
+ rtnl_prop_list_size(dev)
+ nla_total_size(MAX_ADDR_LEN) /* IFLA_PERM_ADDRESS */
+ rtnl_devlink_port_size(dev)
+ + rtnl_xdp_features_size() /* IFLA_XDP_FEATURES */
+ 0;
}
@@ -1546,6 +1555,27 @@ static int rtnl_xdp_fill(struct sk_buff *skb,
struct net_device *dev)
return err;
}
+static int rtnl_xdp_features_fill(struct sk_buff *skb, struct net_device
*dev)
+{
+ struct nlattr *attr;
+
+ attr = nla_nest_start_noflag(skb, IFLA_XDP_FEATURES);
+ if (!attr)
+ return -EMSGSIZE;
+
+ BUILD_BUG_ON(XDP_FEATURES_WORDS != 1);
+ if (nla_put_u32(skb, IFLA_XDP_FEATURES_BITS_WORD, dev->xdp_features))
+ goto err_cancel;
+
+ nla_nest_end(skb, attr);
+
+ return 0;
+
+err_cancel:
+ nla_nest_cancel(skb, attr);
+ return -EMSGSIZE;
+}
+
static u32 rtnl_get_event(unsigned long event)
{
u32 rtnl_event_type = IFLA_EVENT_NONE;
@@ -1904,6 +1934,9 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb,
if (rtnl_fill_devlink_port(skb, dev))
goto nla_put_failure;
+ if (rtnl_xdp_features_fill(skb, dev))
+ goto nla_put_failure;
+
nlmsg_end(skb, nlh);
return 0;
@@ -1968,6 +2001,7 @@ static const struct nla_policy
ifla_policy[IFLA_MAX+1] = {
[IFLA_TSO_MAX_SIZE] = { .type = NLA_REJECT },
[IFLA_TSO_MAX_SEGS] = { .type = NLA_REJECT },
[IFLA_ALLMULTI] = { .type = NLA_REJECT },
+ [IFLA_XDP_FEATURES] = { .type = NLA_NESTED },
};
static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
diff --git a/tools/include/uapi/linux/if_link.h
b/tools/include/uapi/linux/if_link.h
index 82fe18f26db5..994228e9909a 100644
--- a/tools/include/uapi/linux/if_link.h
+++ b/tools/include/uapi/linux/if_link.h
@@ -354,6 +354,8 @@ enum {
IFLA_DEVLINK_PORT,
+ IFLA_XDP_FEATURES,
+
__IFLA_MAX
};
@@ -1222,6 +1224,11 @@ enum {
#define IFLA_XDP_MAX (__IFLA_XDP_MAX - 1)
+enum {
+ IFLA_XDP_FEATURES_WORD_UNSPEC = 0,
+ IFLA_XDP_FEATURES_BITS_WORD,
+};
+
enum {
IFLA_EVENT_NONE,
IFLA_EVENT_REBOOT, /* internal reset / reboot */
diff --git a/tools/include/uapi/linux/xdp_features.h
b/tools/include/uapi/linux/xdp_features.h
new file mode 100644
index 000000000000..48eb42069bcd
--- /dev/null
+++ b/tools/include/uapi/linux/xdp_features.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2020 Intel
+ */
+
+#ifndef __UAPI_LINUX_XDP_FEATURES__
+#define __UAPI_LINUX_XDP_FEATURES__
+
+enum {
+ XDP_F_ABORTED_BIT,
+ XDP_F_DROP_BIT,
+ XDP_F_PASS_BIT,
+ XDP_F_TX_BIT,
+ XDP_F_REDIRECT_BIT,
+ XDP_F_REDIRECT_TARGET_BIT,
+ XDP_F_SOCK_ZEROCOPY_BIT,
+ XDP_F_HW_OFFLOAD_BIT,
+ XDP_F_TX_LOCK_BIT,
+ XDP_F_FRAG_RX_BIT,
+ XDP_F_FRAG_TARGET_BIT,
+ /*
+ * Add your fresh new property above and remember to update
+ * documentation.
+ */
+ XDP_FEATURES_COUNT,
+};
+
+#define XDP_FEATURES_WORDS ((XDP_FEATURES_COUNT + 32 - 1) / 32)
+#define XDP_FEATURES_WORD(blocks, index) ((blocks)[(index) / 32U])
+#define XDP_FEATURES_FIELD_FLAG(index) (1U << (index) % 32U)
+#define XDP_FEATURES_BIT_IS_SET(blocks, index) \
+ (XDP_FEATURES_WORD(blocks, index) & XDP_FEATURES_FIELD_FLAG(index))
+
+#endif /* __UAPI_LINUX_XDP_FEATURES__ */
--
2.38.1
