From: Edward Cree <ecree.xilinx@gmail.com>
Date: Mon, 26 Sep 2022 19:57:36 +0100
Subject: sfc: bare bones TC offload on EF100
Patch-mainline: v6.1-rc1
Git-commit: d902e1a737d44e678eeb981df11c842c2cc1db74
References: jsc#PED-1565
This is the absolute minimum viable TC implementation to get traffic to
VFs and allow them to be tested; it supports no match fields besides
ingress port, no actions besides mirred and drop, and no stats.
Example usage:
tc filter add dev $PF parent ffff: flower skip_sw \
action mirred egress mirror dev $VFREP
tc filter add dev $VFREP parent ffff: flower skip_sw \
action mirred egress redirect dev $PF
gives a VF unfiltered access to the network out the physical port ($PF
acts here as a physical port representor).
More matches, actions, and counters will be added in subsequent patches.
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/sfc/mae.c | 109 ++++++++++++++++
drivers/net/ethernet/sfc/mae.h | 4
drivers/net/ethernet/sfc/mcdi.h | 10 +
drivers/net/ethernet/sfc/tc.c | 272 ++++++++++++++++++++++++++++++++++++++++
drivers/net/ethernet/sfc/tc.h | 2
5 files changed, 397 insertions(+)
--- a/drivers/net/ethernet/sfc/mae.c
+++ b/drivers/net/ethernet/sfc/mae.c
@@ -168,6 +168,111 @@ int efx_mae_get_caps(struct efx_nic *efx
caps->action_rule_fields);
}
+/* Bit twiddling:
+ * Prefix: 1...110...0
+ * ~: 0...001...1
+ * + 1: 0...010...0 is power of two
+ * so (~x) & ((~x) + 1) == 0. Converse holds also.
+ */
+#define is_prefix_byte(_x) !(((_x) ^ 0xff) & (((_x) ^ 0xff) + 1))
+
+enum mask_type { MASK_ONES, MASK_ZEROES, MASK_PREFIX, MASK_OTHER };
+
+static const char *mask_type_name(enum mask_type typ)
+{
+ switch (typ) {
+ case MASK_ONES:
+ return "all-1s";
+ case MASK_ZEROES:
+ return "all-0s";
+ case MASK_PREFIX:
+ return "prefix";
+ case MASK_OTHER:
+ return "arbitrary";
+ default: /* can't happen */
+ return "unknown";
+ }
+}
+
+/* Checks a (big-endian) bytestring is a bit prefix */
+static enum mask_type classify_mask(const u8 *mask, size_t len)
+{
+ bool zeroes = true; /* All bits seen so far are zeroes */
+ bool ones = true; /* All bits seen so far are ones */
+ bool prefix = true; /* Valid prefix so far */
+ size_t i;
+
+ for (i = 0; i < len; i++) {
+ if (ones) {
+ if (!is_prefix_byte(mask[i]))
+ prefix = false;
+ } else if (mask[i]) {
+ prefix = false;
+ }
+ if (mask[i] != 0xff)
+ ones = false;
+ if (mask[i])
+ zeroes = false;
+ }
+ if (ones)
+ return MASK_ONES;
+ if (zeroes)
+ return MASK_ZEROES;
+ if (prefix)
+ return MASK_PREFIX;
+ return MASK_OTHER;
+}
+
+static int efx_mae_match_check_cap_typ(u8 support, enum mask_type typ)
+{
+ switch (support) {
+ case MAE_FIELD_UNSUPPORTED:
+ case MAE_FIELD_SUPPORTED_MATCH_NEVER:
+ if (typ == MASK_ZEROES)
+ return 0;
+ return -EOPNOTSUPP;
+ case MAE_FIELD_SUPPORTED_MATCH_OPTIONAL:
+ if (typ == MASK_ZEROES)
+ return 0;
+ fallthrough;
+ case MAE_FIELD_SUPPORTED_MATCH_ALWAYS:
+ if (typ == MASK_ONES)
+ return 0;
+ return -EINVAL;
+ case MAE_FIELD_SUPPORTED_MATCH_PREFIX:
+ if (typ == MASK_OTHER)
+ return -EOPNOTSUPP;
+ return 0;
+ case MAE_FIELD_SUPPORTED_MATCH_MASK:
+ return 0;
+ default:
+ return -EIO;
+ }
+}
+
+int efx_mae_match_check_caps(struct efx_nic *efx,
+ const struct efx_tc_match_fields *mask,
+ struct netlink_ext_ack *extack)
+{
+ const u8 *supported_fields = efx->tc->caps->action_rule_fields;
+ __be32 ingress_port = cpu_to_be32(mask->ingress_port);
+ enum mask_type ingress_port_mask_type;
+ int rc;
+
+ /* Check for _PREFIX assumes big-endian, so we need to convert */
+ ingress_port_mask_type = classify_mask((const u8 *)&ingress_port,
+ sizeof(ingress_port));
+ rc = efx_mae_match_check_cap_typ(supported_fields[MAE_FIELD_INGRESS_PORT],
+ ingress_port_mask_type);
+ if (rc) {
+ efx_tc_err(efx, "No support for %s mask in field ingress_port\n",
+ mask_type_name(ingress_port_mask_type));
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported mask type for ingress_port");
+ return rc;
+ }
+ return 0;
+}
+
static bool efx_mae_asl_id(u32 id)
{
return !!(id & BIT(31));
@@ -335,6 +440,10 @@ static int efx_mae_populate_match_criter
}
MCDI_STRUCT_SET_DWORD(match_crit, MAE_FIELD_MASK_VALUE_PAIRS_V2_INGRESS_MPORT_SELECTOR_MASK,
match->mask.ingress_port);
+ MCDI_STRUCT_SET_BYTE(match_crit, MAE_FIELD_MASK_VALUE_PAIRS_V2_RECIRC_ID,
+ match->value.recirc_id);
+ MCDI_STRUCT_SET_BYTE(match_crit, MAE_FIELD_MASK_VALUE_PAIRS_V2_RECIRC_ID_MASK,
+ match->mask.recirc_id);
return 0;
}
--- a/drivers/net/ethernet/sfc/mae.h
+++ b/drivers/net/ethernet/sfc/mae.h
@@ -37,6 +37,10 @@ struct mae_caps {
int efx_mae_get_caps(struct efx_nic *efx, struct mae_caps *caps);
+int efx_mae_match_check_caps(struct efx_nic *efx,
+ const struct efx_tc_match_fields *mask,
+ struct netlink_ext_ack *extack);
+
int efx_mae_alloc_action_set(struct efx_nic *efx, struct efx_tc_action_set *act);
int efx_mae_free_action_set(struct efx_nic *efx, u32 fw_id);
--- a/drivers/net/ethernet/sfc/mcdi.h
+++ b/drivers/net/ethernet/sfc/mcdi.h
@@ -201,6 +201,12 @@ void efx_mcdi_sensor_event(struct efx_ni
((u8 *)(_buf) + (_offset))
#define MCDI_PTR(_buf, _field) \
_MCDI_PTR(_buf, MC_CMD_ ## _field ## _OFST)
+/* Use MCDI_STRUCT_ functions to access members of MCDI structuredefs.
+ * _buf should point to the start of the structure, typically obtained with
+ * MCDI_DECLARE_STRUCT_PTR(structure) = _MCDI_DWORD(mcdi_buf, FIELD_WHICH_IS_STRUCT);
+ */
+#define MCDI_STRUCT_PTR(_buf, _field) \
+ _MCDI_PTR(_buf, _field ## _OFST)
#define _MCDI_CHECK_ALIGN(_ofst, _align) \
((_ofst) + BUILD_BUG_ON_ZERO((_ofst) & (_align - 1)))
#define _MCDI_DWORD(_buf, _field) \
@@ -208,6 +214,10 @@ void efx_mcdi_sensor_event(struct efx_ni
#define _MCDI_STRUCT_DWORD(_buf, _field) \
((_buf) + (_MCDI_CHECK_ALIGN(_field ## _OFST, 4) >> 2))
+#define MCDI_STRUCT_SET_BYTE(_buf, _field, _value) do { \
+ BUILD_BUG_ON(_field ## _LEN != 1); \
+ *(u8 *)MCDI_STRUCT_PTR(_buf, _field) = _value; \
+ } while (0)
#define MCDI_BYTE(_buf, _field) \
((void)BUILD_BUG_ON_ZERO(MC_CMD_ ## _field ## _LEN != 1), \
*MCDI_PTR(_buf, _field))
--- a/drivers/net/ethernet/sfc/tc.c
+++ b/drivers/net/ethernet/sfc/tc.c
@@ -9,6 +9,7 @@
* by the Free Software Foundation, incorporated herein by reference.
*/
+#include <net/pkt_cls.h>
#include "tc.h"
#include "tc_bindings.h"
#include "mae.h"
@@ -42,6 +43,20 @@ static struct efx_rep *efx_tc_flower_loo
return efv;
}
+/* Convert a driver-internal vport ID into an external device (wire or VF) */
+static s64 efx_tc_flower_external_mport(struct efx_nic *efx, struct efx_rep *efv)
+{
+ u32 mport;
+
+ if (IS_ERR(efv))
+ return PTR_ERR(efv);
+ if (!efv) /* device is PF (us) */
+ efx_mae_mport_wire(efx, &mport);
+ else /* device is repr */
+ efx_mae_mport_mport(efx, efv->mport, &mport);
+ return mport;
+}
+
static const struct rhashtable_params efx_tc_match_action_ht_params = {
.key_len = sizeof(unsigned long),
.key_offset = offsetof(struct efx_tc_flow_rule, cookie),
@@ -109,6 +124,260 @@ static void efx_tc_flow_free(void *ptr,
kfree(rule);
}
+static int efx_tc_flower_parse_match(struct efx_nic *efx,
+ struct flow_rule *rule,
+ struct efx_tc_match *match,
+ struct netlink_ext_ack *extack)
+{
+ struct flow_dissector *dissector = rule->match.dissector;
+
+ if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_CONTROL)) {
+ struct flow_match_control fm;
+
+ flow_rule_match_control(rule, &fm);
+
+ if (fm.mask->flags) {
+ efx_tc_err(efx, "Unsupported match on control.flags %#x\n",
+ fm.mask->flags);
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported match on control.flags");
+ return -EOPNOTSUPP;
+ }
+ }
+ if (dissector->used_keys &
+ ~(BIT(FLOW_DISSECTOR_KEY_CONTROL) |
+ BIT(FLOW_DISSECTOR_KEY_BASIC))) {
+ efx_tc_err(efx, "Unsupported flower keys %#x\n", dissector->used_keys);
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported flower keys encountered");
+ return -EOPNOTSUPP;
+ }
+
+ if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_BASIC)) {
+ struct flow_match_basic fm;
+
+ flow_rule_match_basic(rule, &fm);
+ if (fm.mask->n_proto) {
+ EFX_TC_ERR_MSG(efx, extack, "Unsupported eth_proto match\n");
+ return -EOPNOTSUPP;
+ }
+ if (fm.mask->ip_proto) {
+ EFX_TC_ERR_MSG(efx, extack, "Unsupported ip_proto match\n");
+ return -EOPNOTSUPP;
+ }
+ }
+
+ return 0;
+}
+
+static int efx_tc_flower_replace(struct efx_nic *efx,
+ struct net_device *net_dev,
+ struct flow_cls_offload *tc,
+ struct efx_rep *efv)
+{
+ struct flow_rule *fr = flow_cls_offload_flow_rule(tc);
+ struct netlink_ext_ack *extack = tc->common.extack;
+ struct efx_tc_flow_rule *rule = NULL, *old;
+ struct efx_tc_action_set *act = NULL;
+ const struct flow_action_entry *fa;
+ struct efx_rep *from_efv, *to_efv;
+ struct efx_tc_match match;
+ s64 rc;
+ int i;
+
+ if (!tc_can_offload_extack(efx->net_dev, extack))
+ return -EOPNOTSUPP;
+ if (WARN_ON(!efx->tc))
+ return -ENETDOWN;
+ if (WARN_ON(!efx->tc->up))
+ return -ENETDOWN;
+
+ from_efv = efx_tc_flower_lookup_efv(efx, net_dev);
+ if (IS_ERR(from_efv)) {
+ /* Might be a tunnel decap rule from an indirect block.
+ * Support for those not implemented yet.
+ */
+ return -EOPNOTSUPP;
+ }
+
+ if (efv != from_efv) {
+ /* can't happen */
+ efx_tc_err(efx, "for %s efv is %snull but from_efv is %snull\n",
+ netdev_name(net_dev), efv ? "non-" : "",
+ from_efv ? "non-" : "");
+ if (efv)
+ NL_SET_ERR_MSG_MOD(extack, "vfrep filter has PF net_dev (can't happen)");
+ else
+ NL_SET_ERR_MSG_MOD(extack, "PF filter has vfrep net_dev (can't happen)");
+ return -EINVAL;
+ }
+
+ /* Parse match */
+ memset(&match, 0, sizeof(match));
+ rc = efx_tc_flower_external_mport(efx, from_efv);
+ if (rc < 0) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to identify ingress m-port");
+ return rc;
+ }
+ match.value.ingress_port = rc;
+ match.mask.ingress_port = ~0;
+ rc = efx_tc_flower_parse_match(efx, fr, &match, extack);
+ if (rc)
+ return rc;
+
+ if (tc->common.chain_index) {
+ EFX_TC_ERR_MSG(efx, extack, "No support for nonzero chain_index");
+ return -EOPNOTSUPP;
+ }
+ match.mask.recirc_id = 0xff;
+
+ rc = efx_mae_match_check_caps(efx, &match.mask, extack);
+ if (rc)
+ return rc;
+
+ rule = kzalloc(sizeof(*rule), GFP_USER);
+ if (!rule)
+ return -ENOMEM;
+ INIT_LIST_HEAD(&rule->acts.list);
+ rule->cookie = tc->cookie;
+ old = rhashtable_lookup_get_insert_fast(&efx->tc->match_action_ht,
+ &rule->linkage,
+ efx_tc_match_action_ht_params);
+ if (old) {
+ netif_dbg(efx, drv, efx->net_dev,
+ "Already offloaded rule (cookie %lx)\n", tc->cookie);
+ rc = -EEXIST;
+ NL_SET_ERR_MSG_MOD(extack, "Rule already offloaded");
+ goto release;
+ }
+
+ /* Parse actions */
+ act = kzalloc(sizeof(*act), GFP_USER);
+ if (!act) {
+ rc = -ENOMEM;
+ goto release;
+ }
+
+ flow_action_for_each(i, fa, &fr->action) {
+ struct efx_tc_action_set save;
+
+ if (!act) {
+ /* more actions after a non-pipe action */
+ EFX_TC_ERR_MSG(efx, extack, "Action follows non-pipe action");
+ rc = -EINVAL;
+ goto release;
+ }
+
+ switch (fa->id) {
+ case FLOW_ACTION_DROP:
+ rc = efx_mae_alloc_action_set(efx, act);
+ if (rc) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to write action set to hw (drop)");
+ goto release;
+ }
+ list_add_tail(&act->list, &rule->acts.list);
+ act = NULL; /* end of the line */
+ break;
+ case FLOW_ACTION_REDIRECT:
+ case FLOW_ACTION_MIRRED:
+ save = *act;
+ to_efv = efx_tc_flower_lookup_efv(efx, fa->dev);
+ if (IS_ERR(to_efv)) {
+ EFX_TC_ERR_MSG(efx, extack, "Mirred egress device not on switch");
+ rc = PTR_ERR(to_efv);
+ goto release;
+ }
+ rc = efx_tc_flower_external_mport(efx, to_efv);
+ if (rc < 0) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to identify egress m-port");
+ goto release;
+ }
+ act->dest_mport = rc;
+ act->deliver = 1;
+ rc = efx_mae_alloc_action_set(efx, act);
+ if (rc) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to write action set to hw (mirred)");
+ goto release;
+ }
+ list_add_tail(&act->list, &rule->acts.list);
+ act = NULL;
+ if (fa->id == FLOW_ACTION_REDIRECT)
+ break; /* end of the line */
+ /* Mirror, so continue on with saved act */
+ act = kzalloc(sizeof(*act), GFP_USER);
+ if (!act) {
+ rc = -ENOMEM;
+ goto release;
+ }
+ *act = save;
+ break;
+ default:
+ efx_tc_err(efx, "Unhandled action %u\n", fa->id);
+ rc = -EOPNOTSUPP;
+ NL_SET_ERR_MSG_MOD(extack, "Unsupported action");
+ goto release;
+ }
+ }
+
+ if (act) {
+ /* Not shot/redirected, so deliver to default dest */
+ if (from_efv == EFX_EFV_PF)
+ /* Rule applies to traffic from the wire,
+ * and default dest is thus the PF
+ */
+ efx_mae_mport_uplink(efx, &act->dest_mport);
+ else
+ /* Representor, so rule applies to traffic from
+ * representee, and default dest is thus the rep.
+ * All reps use the same mport for delivery
+ */
+ efx_mae_mport_mport(efx, efx->tc->reps_mport_id,
+ &act->dest_mport);
+ act->deliver = 1;
+ rc = efx_mae_alloc_action_set(efx, act);
+ if (rc) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to write action set to hw (deliver)");
+ goto release;
+ }
+ list_add_tail(&act->list, &rule->acts.list);
+ act = NULL; /* Prevent double-free in error path */
+ }
+
+ netif_dbg(efx, drv, efx->net_dev,
+ "Successfully parsed filter (cookie %lx)\n",
+ tc->cookie);
+
+ rule->match = match;
+
+ rc = efx_mae_alloc_action_set_list(efx, &rule->acts);
+ if (rc) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to write action set list to hw");
+ goto release;
+ }
+ rc = efx_mae_insert_rule(efx, &rule->match, EFX_TC_PRIO_TC,
+ rule->acts.fw_id, &rule->fw_id);
+ if (rc) {
+ EFX_TC_ERR_MSG(efx, extack, "Failed to insert rule in hw");
+ goto release_acts;
+ }
+ return 0;
+
+release_acts:
+ efx_mae_free_action_set_list(efx, &rule->acts);
+release:
+ /* We failed to insert the rule, so free up any entries we created in
+ * subsidiary tables.
+ */
+ if (act)
+ efx_tc_free_action_set(efx, act, false);
+ if (rule) {
+ rhashtable_remove_fast(&efx->tc->match_action_ht,
+ &rule->linkage,
+ efx_tc_match_action_ht_params);
+ efx_tc_free_action_set_list(efx, &rule->acts, false);
+ }
+ kfree(rule);
+ return rc;
+}
+
static int efx_tc_flower_destroy(struct efx_nic *efx,
struct net_device *net_dev,
struct flow_cls_offload *tc)
@@ -151,6 +420,9 @@ int efx_tc_flower(struct efx_nic *efx, s
mutex_lock(&efx->tc->mutex);
switch (tc->command) {
+ case FLOW_CLS_REPLACE:
+ rc = efx_tc_flower_replace(efx, net_dev, tc, efv);
+ break;
case FLOW_CLS_DESTROY:
rc = efx_tc_flower_destroy(efx, net_dev, tc);
break;
--- a/drivers/net/ethernet/sfc/tc.h
+++ b/drivers/net/ethernet/sfc/tc.h
@@ -43,6 +43,7 @@ struct efx_tc_action_set {
struct efx_tc_match_fields {
/* L1 */
u32 ingress_port;
+ u8 recirc_id;
};
struct efx_tc_match {
@@ -64,6 +65,7 @@ struct efx_tc_flow_rule {
};
enum efx_tc_rule_prios {
+ EFX_TC_PRIO_TC, /* Rule inserted by TC */
EFX_TC_PRIO_DFLT, /* Default switch rule; one of efx_tc_default_rules */
EFX_TC_PRIO__NUM
};