mac80211: Adapt to changes to skb_get_hash_perturb()

The skb_get_hash_perturb() function now takes a siphash_key_t instead of
an u32. This was changed in commit 55667441c84f ("net/flow_dissector:
switch to siphash"). Use the correct type in the fq header file
depending on the kernel version.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Stefan Lippers-Hollmann <s.l-h@gmx.de>
(cherry picked from commit eaa047179ad30d156d0c3da7ec225acfae7a9f00)

package/kernel/mac80211/patches/subsys/370-backports-Adapt-to-changes-to-skb_get_hash_perturb.patch

@@ -0,0 +1,68 @@
+From e3c57dd949835419cee8d3b45db38de58bf6ebd5 Mon Sep 17 00:00:00 2001
+From: Hauke Mehrtens <hauke@hauke-m.de>
+Date: Mon, 18 Nov 2019 01:13:37 +0100
+Subject: [PATCH] backports: Adapt to changes to skb_get_hash_perturb()
+
+The skb_get_hash_perturb() function now takes a siphash_key_t instead of
+an u32. This was changed in commit 55667441c84f ("net/flow_dissector:
+switch to siphash"). Use the correct type in the fq header file
+depending on the kernel version.
+
+Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
+---
+ include/net/fq.h      | 8 ++++++++
+ include/net/fq_impl.h | 8 ++++++++
+ 2 files changed, 16 insertions(+)
+
+--- a/include/net/fq.h
++++ b/include/net/fq.h
+@@ -70,7 +70,15 @@ struct fq {
+ 	struct list_head backlogs;
+ 	spinlock_t lock;
+ 	u32 flows_cnt;
++#if LINUX_VERSION_IS_GEQ(5,3,10) || \
++    LINUX_VERSION_IN_RANGE(4,19,83, 4,20,0) || \
++    LINUX_VERSION_IN_RANGE(4,14,153, 4,15,0) || \
++    LINUX_VERSION_IN_RANGE(4,9,200, 4,10,0) || \
++    LINUX_VERSION_IN_RANGE(4,4,200, 4,5,0)
++	siphash_key_t	perturbation;
++#else
+ 	u32 perturbation;
++#endif
+ 	u32 limit;
+ 	u32 memory_limit;
+ 	u32 memory_usage;
+--- a/include/net/fq_impl.h
++++ b/include/net/fq_impl.h
+@@ -109,7 +109,15 @@ begin:
+ 
+ static u32 fq_flow_idx(struct fq *fq, struct sk_buff *skb)
+ {
++#if LINUX_VERSION_IS_GEQ(5,3,10) || \
++    LINUX_VERSION_IN_RANGE(4,19,83, 4,20,0) || \
++    LINUX_VERSION_IN_RANGE(4,14,153, 4,15,0) || \
++    LINUX_VERSION_IN_RANGE(4,9,200, 4,10,0) || \
++    LINUX_VERSION_IN_RANGE(4,4,200, 4,5,0)
++	u32 hash = skb_get_hash_perturb(skb, &fq->perturbation);
++#else
+ 	u32 hash = skb_get_hash_perturb(skb, fq->perturbation);
++#endif
+ 
+ 	return reciprocal_scale(hash, fq->flows_cnt);
+ }
+@@ -309,7 +317,15 @@ static int fq_init(struct fq *fq, int fl
+ 	INIT_LIST_HEAD(&fq->backlogs);
+ 	spin_lock_init(&fq->lock);
+ 	fq->flows_cnt = max_t(u32, flows_cnt, 1);
++#if LINUX_VERSION_IS_GEQ(5,3,10) || \
++    LINUX_VERSION_IN_RANGE(4,19,83, 4,20,0) || \
++    LINUX_VERSION_IN_RANGE(4,14,153, 4,15,0) || \
++    LINUX_VERSION_IN_RANGE(4,9,200, 4,10,0) || \
++    LINUX_VERSION_IN_RANGE(4,4,200, 4,5,0)
++	get_random_bytes(&fq->perturbation, sizeof(fq->perturbation));
++#else
+ 	fq->perturbation = prandom_u32();
++#endif
+ 	fq->quantum = 300;
+ 	fq->limit = 8192;
+ 	fq->memory_limit = 16 << 20; /* 16 MBytes */