ice: switch: add and use u16[] aliases to ice_adv_lkup_elem::{h, m}_u

ice_adv_lkup_elem fields h_u and m_u are being accessed as raw u16
arrays in several places.
To reduce cast and braces burden, add permanent array-of-u16 aliases
with the same size as the `union ice_prot_hdr` itself via anonymous
unions to the actual struct declaration, and just access them
directly.

This:
 - removes the need to cast the union to u16[] and then dereference
   it each time -> reduces the horizon for potential bugs;
 - improves -Warray-bounds coverage -- the array size is now known
   at compilation time;
 - addresses cppcheck complaints.

Signed-off-by: Alexander Lobakin <alexandr.lobakin@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Tested-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Tested-by: Sandeep Penigalapati <sandeep.penigalapati@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/ice/ice_switch.c b/drivers/net/ethernet/intel/ice/ice_switch.c
index 25b8f6f..075df24 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_switch.c
+++ b/drivers/net/ethernet/intel/ice/ice_switch.c
@@ -5811,12 +5811,12 @@ ice_fill_adv_dummy_packet(struct ice_adv_lkup_elem *lkups, u16 lkups_cnt,
                 * over any significant packet data.
                 */
                for (j = 0; j < len / sizeof(u16); j++)
-                       if (((u16 *)&lkups[i].m_u)[j])
+                       if (lkups[i].m_raw[j])
                                ((u16 *)(pkt + offset))[j] =
                                        (((u16 *)(pkt + offset))[j] &
-                                        ~((u16 *)&lkups[i].m_u)[j]) |
-                                       (((u16 *)&lkups[i].h_u)[j] &
-                                        ((u16 *)&lkups[i].m_u)[j]);
+                                        ~lkups[i].m_raw[j]) |
+                                       (lkups[i].h_raw[j] &
+                                        lkups[i].m_raw[j]);
        }
 
        s_rule->pdata.lkup_tx_rx.hdr_len = cpu_to_le16(pkt_len);
@@ -6065,11 +6065,10 @@ ice_add_adv_rule(struct ice_hw *hw, struct ice_adv_lkup_elem *lkups,
        /* get # of words we need to match */
        word_cnt = 0;
        for (i = 0; i < lkups_cnt; i++) {
-               u16 j, *ptr;
+               u16 j;
 
-               ptr = (u16 *)&lkups[i].m_u;
-               for (j = 0; j < sizeof(lkups->m_u) / sizeof(u16); j++)
-                       if (ptr[j] != 0)
+               for (j = 0; j < ARRAY_SIZE(lkups->m_raw); j++)
+                       if (lkups[i].m_raw[j])
                                word_cnt++;
        }
 

diff --git a/drivers/net/ethernet/intel/ice/ice_switch.h b/drivers/net/ethernet/intel/ice/ice_switch.h
index ed3d1d0..ecac75e 100644 (file)
--- a/drivers/net/ethernet/intel/ice/ice_switch.h
+++ b/drivers/net/ethernet/intel/ice/ice_switch.h
@@ -138,8 +138,16 @@ struct ice_update_recipe_lkup_idx_params {
 
 struct ice_adv_lkup_elem {
        enum ice_protocol_type type;
-       union ice_prot_hdr h_u; /* Header values */
-       union ice_prot_hdr m_u; /* Mask of header values to match */
+       union {
+               union ice_prot_hdr h_u; /* Header values */
+               /* Used to iterate over the headers */
+               u16 h_raw[sizeof(union ice_prot_hdr) / sizeof(u16)];
+       };
+       union {
+               union ice_prot_hdr m_u; /* Mask of header values to match */
+               /* Used to iterate over header mask */
+               u16 m_raw[sizeof(union ice_prot_hdr) / sizeof(u16)];
+       };
 };
 
 struct ice_sw_act_ctrl {