sfc: Don't use efx_filter_{build,hash,increment}() for default MAC filters

These functions happen to work for default MAC filters: they generate
an initial index of 1/0 for unicast/multicast respectively and an
increment of 1 for either, so a search succeeds at depth 2.  But this
is a matter of luck rather than design, and it really won't work well
with the bug fix we're about to do.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

1 files changed, 19 insertions, 16 deletions

diff --git a/drivers/net/ethernet/sfc/filter.c b/drivers/net/ethernet/sfc/filter.c
index 3d94ed73c65e..8d83d9832b21 100644
--- a/drivers/net/ethernet/sfc/filter.c
+++ b/drivers/net/ethernet/sfc/filter.c
@@ -463,13 +463,6 @@ static u32 efx_filter_build(efx_oword_t *filter, struct efx_filter_spec *spec)
                 break;
         }
 
-        case EFX_FILTER_TABLE_RX_DEF:
-                /* One filter spec per type */
-                BUILD_BUG_ON(EFX_FILTER_INDEX_UC_DEF != 0);
-                BUILD_BUG_ON(EFX_FILTER_INDEX_MC_DEF !=
-                             EFX_FILTER_MC_DEF - EFX_FILTER_UC_DEF);
-                return spec->type - EFX_FILTER_UC_DEF;
-
         case EFX_FILTER_TABLE_RX_MAC: {
                 bool is_wild = spec->type == EFX_FILTER_MAC_WILD;
                 EFX_POPULATE_OWORD_7(
@@ -667,25 +660,35 @@ s32 efx_filter_insert_filter(struct efx_nic *efx, struct efx_filter_spec *spec,
         struct efx_filter_spec *saved_spec;
         efx_oword_t filter;
         unsigned int filter_idx, depth = 0;
-        u32 key;
         int rc;
 
         if (!table || table->size == 0)
                 return -EINVAL;
 
-        key = efx_filter_build(&filter, spec);
-
         netif_vdbg(efx, hw, efx->net_dev,
                    "%s: type %d search_depth=%d", __func__, spec->type,
                    table->search_depth[spec->type]);
 
-        spin_lock_bh(&state->lock);
+        if (table->id == EFX_FILTER_TABLE_RX_DEF) {
+                /* One filter spec per type */
+                BUILD_BUG_ON(EFX_FILTER_INDEX_UC_DEF != 0);
+                BUILD_BUG_ON(EFX_FILTER_INDEX_MC_DEF !=
+                             EFX_FILTER_MC_DEF - EFX_FILTER_UC_DEF);
+                filter_idx = spec->type - EFX_FILTER_INDEX_UC_DEF;
+
+                spin_lock_bh(&state->lock);
+        } else {
+                u32 key = efx_filter_build(&filter, spec);
+
+                spin_lock_bh(&state->lock);
+
+                rc = efx_filter_search(table, spec, key, &depth);
+                if (rc < 0)
+                        goto out;
+                filter_idx = rc;
+                BUG_ON(filter_idx >= table->size);
+        }
 
-        rc = efx_filter_search(table, spec, key, &depth);
-        if (rc < 0)
-                goto out;
-        filter_idx = rc;
-        BUG_ON(filter_idx >= table->size);
         saved_spec = &table->spec[filter_idx];
 
         if (test_bit(filter_idx, table->used_bitmap)) {