sfc: Fix the reported priorities of different filter types

Each RX filter table contains filters with two different levels of
specificity: TCP/IPv4 and UDP/IPv4 filters match the local address and
port and optionally the remote address and port; Ethernet filters
match the local address and optionally the VID.  The more specific
filters always override less specific filters within the same table,
and should be numbered accordingly.

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

1 files changed, 53 insertions, 16 deletions

diff --git a/drivers/net/ethernet/sfc/filter.c b/drivers/net/ethernet/sfc/filter.c
index e89bad78312e..8af42cd1feda 100644
--- a/drivers/net/ethernet/sfc/filter.c
+++ b/drivers/net/ethernet/sfc/filter.c
@@ -557,26 +557,62 @@ static int efx_filter_search(struct efx_filter_table *table,
 }
 
 /*
- * Construct/deconstruct external filter IDs.  These must be ordered
- * by matching priority, for RX NFC semantics.
+ * Construct/deconstruct external filter IDs.  At least the RX filter
+ * IDs must be ordered by matching priority, for RX NFC semantics.
+ *
+ * Deconstruction needs to be robust against invalid IDs so that
+ * efx_filter_remove_id_safe() and efx_filter_get_filter_safe() can
+ * accept user-provided IDs.
  */
 
+#define EFX_FILTER_MATCH_PRI_COUNT      5
+
+static const u8 efx_filter_type_match_pri[EFX_FILTER_TYPE_COUNT] = {
+        [EFX_FILTER_TCP_FULL]   = 0,
+        [EFX_FILTER_UDP_FULL]   = 0,
+        [EFX_FILTER_TCP_WILD]   = 1,
+        [EFX_FILTER_UDP_WILD]   = 1,
+        [EFX_FILTER_MAC_FULL]   = 2,
+        [EFX_FILTER_MAC_WILD]   = 3,
+        [EFX_FILTER_UC_DEF]     = 4,
+        [EFX_FILTER_MC_DEF]     = 4,
+};
+
+static const enum efx_filter_table_id efx_filter_range_table[] = {
+        EFX_FILTER_TABLE_RX_IP,         /* RX match pri 0 */
+        EFX_FILTER_TABLE_RX_IP,
+        EFX_FILTER_TABLE_RX_MAC,
+        EFX_FILTER_TABLE_RX_MAC,
+        EFX_FILTER_TABLE_RX_DEF,        /* RX match pri 4 */
+        EFX_FILTER_TABLE_COUNT,         /* TX match pri 0; invalid */
+        EFX_FILTER_TABLE_COUNT,         /* invalid */
+        EFX_FILTER_TABLE_TX_MAC,
+        EFX_FILTER_TABLE_TX_MAC,        /* TX match pri 3 */
+};
+
 #define EFX_FILTER_INDEX_WIDTH  13
 #define EFX_FILTER_INDEX_MASK   ((1 << EFX_FILTER_INDEX_WIDTH) - 1)
 
-static inline u32 efx_filter_make_id(enum efx_filter_table_id table_id,
-                                     unsigned int index, u8 flags)
+static inline u32
+efx_filter_make_id(const struct efx_filter_spec *spec, unsigned int index)
 {
-        unsigned int match_pri = table_id;
+        unsigned int range;
+
+        range = efx_filter_type_match_pri[spec->type];
+        if (!(spec->flags & EFX_FILTER_FLAG_RX))
+                range += EFX_FILTER_MATCH_PRI_COUNT;
 
-        return match_pri << EFX_FILTER_INDEX_WIDTH | index;
+        return range << EFX_FILTER_INDEX_WIDTH | index;
 }
 
 static inline enum efx_filter_table_id efx_filter_id_table_id(u32 id)
 {
-        unsigned int match_pri = id >> EFX_FILTER_INDEX_WIDTH;
+        unsigned int range = id >> EFX_FILTER_INDEX_WIDTH;
 
-        return match_pri;
+        if (range < ARRAY_SIZE(efx_filter_range_table))
+                return efx_filter_range_table[range];
+        else
+                return EFX_FILTER_TABLE_COUNT; /* invalid */
 }
 
 static inline unsigned int efx_filter_id_index(u32 id)
@@ -586,9 +622,9 @@ static inline unsigned int efx_filter_id_index(u32 id)
 
 static inline u8 efx_filter_id_flags(u32 id)
 {
-        unsigned int match_pri = id >> EFX_FILTER_INDEX_WIDTH;
+        unsigned int range = id >> EFX_FILTER_INDEX_WIDTH;
 
-        if (match_pri <= EFX_FILTER_TABLE_RX_DEF)
+        if (range < EFX_FILTER_MATCH_PRI_COUNT)
                 return EFX_FILTER_FLAG_RX;
         else
                 return EFX_FILTER_FLAG_TX;
@@ -597,13 +633,15 @@ static inline u8 efx_filter_id_flags(u32 id)
 u32 efx_filter_get_rx_id_limit(struct efx_nic *efx)
 {
         struct efx_filter_state *state = efx->filter_state;
-        unsigned int table_id = EFX_FILTER_TABLE_RX_DEF;
+        unsigned int range = EFX_FILTER_MATCH_PRI_COUNT - 1;
+        enum efx_filter_table_id table_id;
 
         do {
+                table_id = efx_filter_range_table[range];
                 if (state->table[table_id].size != 0)
-                        return (table_id << EFX_FILTER_INDEX_WIDTH) +
+                        return range << EFX_FILTER_INDEX_WIDTH |
                                 state->table[table_id].size;
-        } while (table_id--);
+        } while (range--);
 
         return 0;
 }
@@ -681,7 +719,7 @@ s32 efx_filter_insert_filter(struct efx_nic *efx, struct efx_filter_spec *spec,
         netif_vdbg(efx, hw, efx->net_dev,
                    "%s: filter type %d index %d rxq %u set",
                    __func__, spec->type, filter_idx, spec->dmaq_id);
-        rc = efx_filter_make_id(table->id, filter_idx, spec->flags);
+        rc = efx_filter_make_id(spec, filter_idx);
 
 out:
         spin_unlock_bh(&state->lock);
@@ -888,8 +926,7 @@ s32 efx_filter_get_rx_ids(struct efx_nic *efx,
                                         goto out;
                                 }
                                 buf[count++] = efx_filter_make_id(
-                                        table_id, filter_idx,
-                                        table->spec[filter_idx].flags);
+                                        &table->spec[filter_idx], filter_idx);
                         }
                 }
         }