bnxt_en: Add separate function to delete the filter structure

Since we are going to do filter deletion at multiple places in the
upcoming patches, add a function that does the deletion.  Future patches
add more code into this function.

Since we are passing the address of the filter base to free the
entire filter structure, add a comment to make sure that the base
is always at the beginning of the structure.
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20240205223202.25341-8-michael.chan@broadcom.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -4841,6 +4841,16 @@ static void bnxt_clear_ring_indices(struct bnxt *bp)
 	}
 }
 
+static void bnxt_del_fltr(struct bnxt *bp, struct bnxt_filter_base *fltr)
+{
+	hlist_del(&fltr->hash);
+	if (fltr->flags) {
+		clear_bit(fltr->sw_id, bp->ntp_fltr_bmap);
+		bp->ntp_fltr_count--;
+	}
+	kfree(fltr);
+}
+
 static void bnxt_free_ntp_fltrs(struct bnxt *bp, bool all)
 {
 	int i;
@@ -4858,10 +4868,7 @@ static void bnxt_free_ntp_fltrs(struct bnxt *bp, bool all)
 			bnxt_del_l2_filter(bp, fltr->l2_fltr);
 			if (!all && (fltr->base.flags & BNXT_ACT_FUNC_DST))
 				continue;
-			hlist_del(&fltr->base.hash);
-			clear_bit(fltr->base.sw_id, bp->ntp_fltr_bmap);
-			bp->ntp_fltr_count--;
-			kfree(fltr);
+			bnxt_del_fltr(bp, &fltr->base);
 		}
 	}
 	if (!all)
@@ -4904,12 +4911,7 @@ static void bnxt_free_l2_filters(struct bnxt *bp, bool all)
 		hlist_for_each_entry_safe(fltr, tmp, head, base.hash) {
 			if (!all && (fltr->base.flags & BNXT_ACT_FUNC_DST))
 				continue;
-			hlist_del(&fltr->base.hash);
-			if (fltr->base.flags) {
-				clear_bit(fltr->base.sw_id, bp->ntp_fltr_bmap);
-				bp->ntp_fltr_count--;
-			}
-			kfree(fltr);
+			bnxt_del_fltr(bp, &fltr->base);
 		}
 	}
 }

drivers/net/ethernet/broadcom/bnxt/bnxt.h

@@ -1365,6 +1365,7 @@ extern const struct bnxt_flow_masks BNXT_FLOW_IPV6_MASK_ALL;
 extern const struct bnxt_flow_masks BNXT_FLOW_IPV4_MASK_ALL;
 
 struct bnxt_ntuple_filter {
+	/* base filter must be the first member */
 	struct bnxt_filter_base	base;
 	struct flow_keys	fkeys;
 	struct bnxt_flow_masks	fmasks;
@@ -1395,6 +1396,7 @@ struct bnxt_ipv6_tuple {
 #define BNXT_L2_KEY_SIZE	(sizeof(struct bnxt_l2_key) / 4)
 
 struct bnxt_l2_filter {
+	/* base filter must be the first member */
 	struct bnxt_filter_base	base;
 	struct bnxt_l2_key	l2_key;
 	atomic_t		refcnt;