diff mbox series

[net-next,2/6] sfc: add mac source and destination pedit action offload

Message ID 20230823111725.28090-3-pieter.jansen-van-vuuren@amd.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series sfc: introduce eth, ipv4 and ipv6 pedit offloads | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1330 this patch: 1330
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 1353 this patch: 1353
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1353 this patch: 1353
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 82 exceeds 80 columns WARNING: line length of 85 exceeds 80 columns WARNING: line length of 90 exceeds 80 columns WARNING: line length of 91 exceeds 80 columns WARNING: line length of 99 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Pieter Jansen van Vuuren Aug. 23, 2023, 11:17 a.m. UTC
Introduce the first pedit set offload functionality for the sfc driver.
In addition to this, add offload functionality for both mac source and
destination pedit set actions.

Co-developed-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
---
 drivers/net/ethernet/sfc/tc.c | 209 +++++++++++++++++++++++++++++++++-
 1 file changed, 207 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/sfc/tc.c b/drivers/net/ethernet/sfc/tc.c
index 8a9fc2f47514..47bf59529a46 100644
--- a/drivers/net/ethernet/sfc/tc.c
+++ b/drivers/net/ethernet/sfc/tc.c
@@ -116,7 +116,7 @@  static const struct rhashtable_params efx_tc_recirc_ht_params = {
 	.head_offset	= offsetof(struct efx_tc_recirc_id, linkage),
 };
 
-static struct efx_tc_mac_pedit_action __maybe_unused *efx_tc_flower_get_mac(struct efx_nic *efx,
+static struct efx_tc_mac_pedit_action *efx_tc_flower_get_mac(struct efx_nic *efx,
 							     unsigned char h_addr[ETH_ALEN],
 							     struct netlink_ext_ack *extack)
 {
@@ -155,7 +155,7 @@  static struct efx_tc_mac_pedit_action __maybe_unused *efx_tc_flower_get_mac(stru
 	return ERR_PTR(rc);
 }
 
-static void __maybe_unused efx_tc_flower_put_mac(struct efx_nic *efx,
+static void efx_tc_flower_put_mac(struct efx_nic *efx,
 				  struct efx_tc_mac_pedit_action *ped)
 {
 	if (!refcount_dec_and_test(&ped->ref))
@@ -191,6 +191,10 @@  static void efx_tc_free_action_set(struct efx_nic *efx,
 		list_del(&act->encap_user);
 		efx_tc_flower_release_encap_md(efx, act->encap_md);
 	}
+	if (act->src_mac)
+		efx_tc_flower_put_mac(efx, act->src_mac);
+	if (act->dst_mac)
+		efx_tc_flower_put_mac(efx, act->dst_mac);
 	kfree(act);
 }
 
@@ -753,6 +757,7 @@  static const char *efx_tc_encap_type_name(enum efx_encap_type typ)
 /* For details of action order constraints refer to SF-123102-TC-1§12.6.1 */
 enum efx_tc_action_order {
 	EFX_TC_AO_DECAP,
+	EFX_TC_AO_PEDIT_MAC_ADDRS,
 	EFX_TC_AO_VLAN_POP,
 	EFX_TC_AO_VLAN_PUSH,
 	EFX_TC_AO_COUNT,
@@ -767,6 +772,11 @@  static bool efx_tc_flower_action_order_ok(const struct efx_tc_action_set *act,
 	case EFX_TC_AO_DECAP:
 		if (act->decap)
 			return false;
+		/* PEDIT_MAC_ADDRS must not happen before DECAP, though it
+		 * can wait until much later
+		 */
+		if (act->dst_mac || act->src_mac)
+			return false;
 		fallthrough;
 	case EFX_TC_AO_VLAN_POP:
 		if (act->vlan_pop >= 2)
@@ -786,6 +796,7 @@  static bool efx_tc_flower_action_order_ok(const struct efx_tc_action_set *act,
 		if (act->count)
 			return false;
 		fallthrough;
+	case EFX_TC_AO_PEDIT_MAC_ADDRS:
 	case EFX_TC_AO_ENCAP:
 		if (act->encap_md)
 			return false;
@@ -956,6 +967,191 @@  static void efx_tc_flower_release_lhs_actions(struct efx_nic *efx,
 		efx_tc_flower_put_counter_index(efx, act->count);
 }
 
+/**
+ * struct efx_tc_mangler_state - accumulates 32-bit pedits into fields
+ *
+ * @dst_mac_32: dst_mac[0:3] has been populated
+ * @dst_mac_16: dst_mac[4:5] has been populated
+ * @src_mac_16: src_mac[0:1] has been populated
+ * @src_mac_32: src_mac[2:5] has been populated
+ * @dst_mac: h_dest field of ethhdr
+ * @src_mac: h_source field of ethhdr
+ *
+ * Since FLOW_ACTION_MANGLE comes in 32-bit chunks that do not
+ * necessarily equate to whole fields of the packet header, this
+ * structure is used to hold the cumulative effect of the partial
+ * field pedits that have been processed so far.
+ */
+struct efx_tc_mangler_state {
+	u8 dst_mac_32:1; /* eth->h_dest[0:3] */
+	u8 dst_mac_16:1; /* eth->h_dest[4:5] */
+	u8 src_mac_16:1; /* eth->h_source[0:1] */
+	u8 src_mac_32:1; /* eth->h_source[2:5] */
+	unsigned char dst_mac[ETH_ALEN];
+	unsigned char src_mac[ETH_ALEN];
+};
+
+/** efx_tc_complete_mac_mangle() - pull complete field pedits out of @mung
+ * @efx: NIC we're installing a flow rule on
+ * @act: action set (cursor) to update
+ * @mung:        accumulated partial mangles
+ * @extack:      netlink extended ack for reporting errors
+ *
+ * Check @mung to find any combinations of partial mangles that can be
+ * combined into a complete packet field edit, add that edit to @act,
+ * and consume the partial mangles from @mung.
+ */
+
+static int efx_tc_complete_mac_mangle(struct efx_nic *efx,
+				      struct efx_tc_action_set *act,
+				      struct efx_tc_mangler_state *mung,
+				      struct netlink_ext_ack *extack)
+{
+	struct efx_tc_mac_pedit_action *ped;
+
+	if (mung->dst_mac_32 && mung->dst_mac_16) {
+		ped = efx_tc_flower_get_mac(efx, mung->dst_mac, extack);
+		if (IS_ERR(ped))
+			return PTR_ERR(ped);
+
+		/* Check that we have not already populated dst_mac */
+		if (act->dst_mac)
+			efx_tc_flower_put_mac(efx, act->dst_mac);
+
+		act->dst_mac = ped;
+
+		/* consume the incomplete state */
+		mung->dst_mac_32 = 0;
+		mung->dst_mac_16 = 0;
+	}
+	if (mung->src_mac_16 && mung->src_mac_32) {
+		ped = efx_tc_flower_get_mac(efx, mung->src_mac, extack);
+		if (IS_ERR(ped))
+			return PTR_ERR(ped);
+
+		/* Check that we have not already populated src_mac */
+		if (act->src_mac)
+			efx_tc_flower_put_mac(efx, act->src_mac);
+
+		act->src_mac = ped;
+
+		/* consume the incomplete state */
+		mung->src_mac_32 = 0;
+		mung->src_mac_16 = 0;
+	}
+	return 0;
+}
+
+/**
+ * efx_tc_mangle() - handle a single 32-bit (or less) pedit
+ * @efx: NIC we're installing a flow rule on
+ * @act: action set (cursor) to update
+ * @fa:          FLOW_ACTION_MANGLE action metadata
+ * @mung:        accumulator for partial mangles
+ * @extack:      netlink extended ack for reporting errors
+ *
+ * Identify the fields written by a FLOW_ACTION_MANGLE, and record
+ * the partial mangle state in @mung.  If this mangle completes an
+ * earlier partial mangle, consume and apply to @act by calling
+ * efx_tc_complete_mac_mangle().
+ */
+
+static int efx_tc_mangle(struct efx_nic *efx, struct efx_tc_action_set *act,
+			 const struct flow_action_entry *fa,
+			 struct efx_tc_mangler_state *mung,
+			 struct netlink_ext_ack *extack)
+{
+	__le32 mac32;
+	__le16 mac16;
+
+	switch (fa->mangle.htype) {
+	case FLOW_ACT_MANGLE_HDR_TYPE_ETH:
+		BUILD_BUG_ON(offsetof(struct ethhdr, h_dest) != 0);
+		BUILD_BUG_ON(offsetof(struct ethhdr, h_source) != 6);
+		if (!efx_tc_flower_action_order_ok(act, EFX_TC_AO_PEDIT_MAC_ADDRS)) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Pedit mangle mac action violates action order");
+			return -EOPNOTSUPP;
+		}
+		switch (fa->mangle.offset) {
+		case 0:
+			if (fa->mangle.mask) {
+				NL_SET_ERR_MSG_FMT_MOD(extack,
+						       "Unsupported: mask (%#x) of eth.dst32 mangle",
+						       fa->mangle.mask);
+				return -EOPNOTSUPP;
+			}
+			/* Ethernet address is little-endian */
+			mac32 = cpu_to_le32(fa->mangle.val);
+			memcpy(mung->dst_mac, &mac32, sizeof(mac32));
+			mung->dst_mac_32 = 1;
+			return efx_tc_complete_mac_mangle(efx, act, mung, extack);
+		case 4:
+			if (fa->mangle.mask == 0xffff) {
+				mac16 = cpu_to_le16(fa->mangle.val >> 16);
+				memcpy(mung->src_mac, &mac16, sizeof(mac16));
+				mung->src_mac_16 = 1;
+			} else if (fa->mangle.mask == 0xffff0000) {
+				mac16 = cpu_to_le16((u16)fa->mangle.val);
+				memcpy(mung->dst_mac + 4, &mac16, sizeof(mac16));
+				mung->dst_mac_16 = 1;
+			} else {
+				NL_SET_ERR_MSG_FMT_MOD(extack,
+						       "Unsupported: mask (%#x) of eth+4 mangle is not high or low 16b",
+						       fa->mangle.mask);
+				return -EOPNOTSUPP;
+			}
+			return efx_tc_complete_mac_mangle(efx, act, mung, extack);
+		case 8:
+			if (fa->mangle.mask) {
+				NL_SET_ERR_MSG_FMT_MOD(extack,
+						       "Unsupported: mask (%#x) of eth.src32 mangle",
+						       fa->mangle.mask);
+				return -EOPNOTSUPP;
+			}
+			mac32 = cpu_to_le32(fa->mangle.val);
+			memcpy(mung->src_mac + 2, &mac32, sizeof(mac32));
+			mung->src_mac_32 = 1;
+			return efx_tc_complete_mac_mangle(efx, act, mung, extack);
+		default:
+			NL_SET_ERR_MSG_FMT_MOD(extack, "Unsupported: mangle eth+%u %x/%x",
+					       fa->mangle.offset, fa->mangle.val, fa->mangle.mask);
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		NL_SET_ERR_MSG_FMT_MOD(extack, "Unhandled mangle htype %u for action rule",
+				       fa->mangle.htype);
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+/**
+ * efx_tc_incomplete_mangle() - check for leftover partial pedits
+ * @mung:        accumulator for partial mangles
+ * @extack:      netlink extended ack for reporting errors
+ *
+ * Since the MAE can only overwrite whole fields, any partial
+ * field mangle left over on reaching packet delivery (mirred or
+ * end of TC actions) cannot be offloaded.  Check for any such
+ * and reject them with -%EOPNOTSUPP.
+ */
+
+static int efx_tc_incomplete_mangle(struct efx_tc_mangler_state *mung,
+				    struct netlink_ext_ack *extack)
+{
+	if (mung->dst_mac_32 || mung->dst_mac_16) {
+		NL_SET_ERR_MSG_MOD(extack, "Incomplete pedit of destination MAC address");
+		return -EOPNOTSUPP;
+	}
+	if (mung->src_mac_16 || mung->src_mac_32) {
+		NL_SET_ERR_MSG_MOD(extack, "Incomplete pedit of source MAC address");
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
 static int efx_tc_flower_replace_foreign(struct efx_nic *efx,
 					 struct net_device *net_dev,
 					 struct flow_cls_offload *tc)
@@ -1351,6 +1547,7 @@  static int efx_tc_flower_replace(struct efx_nic *efx,
 	struct netlink_ext_ack *extack = tc->common.extack;
 	const struct ip_tunnel_info *encap_info = NULL;
 	struct efx_tc_flow_rule *rule = NULL, *old;
+	struct efx_tc_mangler_state mung = {};
 	struct efx_tc_action_set *act = NULL;
 	const struct flow_action_entry *fa;
 	struct efx_rep *from_efv, *to_efv;
@@ -1687,6 +1884,11 @@  static int efx_tc_flower_replace(struct efx_nic *efx,
 			act->vlan_proto[act->vlan_push] = fa->vlan.proto;
 			act->vlan_push++;
 			break;
+		case FLOW_ACTION_MANGLE:
+			rc = efx_tc_mangle(efx, act, fa, &mung, extack);
+			if (rc < 0)
+				goto release;
+			break;
 		case FLOW_ACTION_TUNNEL_ENCAP:
 			if (encap_info) {
 				/* Can't specify encap multiple times.
@@ -1726,6 +1928,9 @@  static int efx_tc_flower_replace(struct efx_nic *efx,
 		}
 	}
 
+	rc = efx_tc_incomplete_mangle(&mung, extack);
+	if (rc < 0)
+		goto release;
 	if (act) {
 		/* Not shot/redirected, so deliver to default dest */
 		if (from_efv == EFX_EFV_PF)