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>

diff --git a/drivers/net/ethernet/sfc/filter.c b/drivers/net/ethernet/sfc/filter.c
index 3d94ed7..8d83d98 100644 (file)
--- 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)) {