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 <[email protected]>
---
drivers/net/ethernet/intel/ice/ice_switch.c | 15 +++++++--------
drivers/net/ethernet/intel/ice/ice_switch.h | 12 ++++++++++--
2 files changed, 17 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/intel/ice/ice_switch.c b/drivers/net/ethernet/intel/ice/ice_switch.c
index d98aa35c0337..7f7e929e73a8 100644
--- a/drivers/net/ethernet/intel/ice/ice_switch.c
+++ b/drivers/net/ethernet/intel/ice/ice_switch.c
@@ -5267,12 +5267,12 @@ 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);
@@ -5521,11 +5521,10 @@ 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 7b42c51a3eb0..950a66e86227 100644
--- a/drivers/net/ethernet/intel/ice/ice_switch.h
+++ b/drivers/net/ethernet/intel/ice/ice_switch.h
@@ -129,8 +129,16 @@ 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 {
--
2.34.1
>-----Original Message-----
>From: Intel-wired-lan <[email protected]> On Behalf Of
>Alexander Lobakin
>Sent: Thursday, January 27, 2022 9:10 PM
>To: [email protected]
>Cc: Szapar-Mudlaw, Martyna <[email protected]>;
>[email protected]; [email protected]; Jakub Kicinski
><[email protected]>; David S. Miller <[email protected]>
>Subject: [Intel-wired-lan] [PATCH v2 net-next 1/4] 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 <[email protected]>
>---
> drivers/net/ethernet/intel/ice/ice_switch.c | 15 +++++++--------
>drivers/net/ethernet/intel/ice/ice_switch.h | 12 ++++++++++--
> 2 files changed, 17 insertions(+), 10 deletions(-)
>
Tested-by: Sandeep Penigalapati <[email protected]>