Perform some rather amusing layering violations to add mbuf tags to the

net80211 receive path.  This allows drivers (notably USB right now, but
anything/everything!) to optionally defer bulk RX of 802.11 frames until
/outside/ of the driver lock(s), rather than doing:

UNLOCK(sc);
ieee80211_input*()
LOCK(sc);

.. which is really stupid.

The existing API is maintaned - if ieee80211_input() / ieee80211_input_all()
is called then the RSSI/NF values are used.  If the MIMO versions are called
with a given rx status pointer then it's used. Else, it'll use whatever
is in the RX mbuf tag.

5 files changed, 103 insertions, 34 deletions

diff --git a/sys/net80211/_ieee80211.h b/sys/net80211/_ieee80211.h
index 5120d41..4ff395d 100644
--- a/sys/net80211/_ieee80211.h
+++ b/sys/net80211/_ieee80211.h
@@ -390,15 +390,14 @@ struct ieee80211_regdomain {
  * MIMO antenna/radio state.
  */
 
-#define	IEEE80211_MAX_CHAINS		3
-#define	IEEE80211_MAX_EVM_PILOTS	6
-
 /*
  * XXX This doesn't yet export both ctl/ext chain details
+ * XXX TODO: IEEE80211_MAX_CHAINS is defined in _freebsd.h, not here;
+ * figure out how to pull it in!
  */
 struct ieee80211_mimo_info {
-	int8_t		rssi[IEEE80211_MAX_CHAINS];	/* per-antenna rssi */
-	int8_t		noise[IEEE80211_MAX_CHAINS];	/* per-antenna noise floor */
+	int8_t		rssi[3];	/* per-antenna rssi */
+	int8_t		noise[3];	/* per-antenna noise floor */
 	uint8_t		pad[2];
 	uint32_t	evm[3];		/* EVM data */
 };
diff --git a/sys/net80211/ieee80211_freebsd.c b/sys/net80211/ieee80211_freebsd.c
index 9a8e941..6fdfb5c 100644
--- a/sys/net80211/ieee80211_freebsd.c
+++ b/sys/net80211/ieee80211_freebsd.c
@@ -491,6 +491,43 @@ ieee80211_process_callback(struct ieee80211_node *ni,
 }
 
 /*
+ * Add RX parameters to the given mbuf.
+ *
+ * Returns 1 if OK, 0 on error.
+ */
+int
+ieee80211_add_rx_params(struct mbuf *m, const struct ieee80211_rx_stats *rxs)
+{
+	struct m_tag *mtag;
+	struct ieee80211_rx_params *rx;
+
+	mtag = m_tag_alloc(MTAG_ABI_NET80211, NET80211_TAG_RECV_PARAMS,
+	    sizeof(struct ieee80211_rx_stats), M_NOWAIT);
+	if (mtag == NULL)
+		return (0);
+
+	rx = (struct ieee80211_rx_params *)(mtag + 1);
+	memcpy(&rx->params, rxs, sizeof(*rxs));
+	m_tag_prepend(m, mtag);
+	return (1);
+}
+
+int
+ieee80211_get_rx_params(struct mbuf *m, struct ieee80211_rx_stats *rxs)
+{
+	struct m_tag *mtag;
+	struct ieee80211_rx_params *rx;
+
+	mtag = m_tag_locate(m, MTAG_ABI_NET80211, NET80211_TAG_RECV_PARAMS,
+	    NULL);
+	if (mtag == NULL)
+		return (-1);
+	rx = (struct ieee80211_rx_params *)(mtag + 1);
+	memcpy(rxs, &rx->params, sizeof(*rxs));
+	return (0);
+}
+
+/*
  * Transmit a frame to the parent interface.
  *
  * TODO: if the transmission fails, make sure the parent node is freed
diff --git a/sys/net80211/ieee80211_freebsd.h b/sys/net80211/ieee80211_freebsd.h
index 162cf43..f660c17 100644
--- a/sys/net80211/ieee80211_freebsd.h
+++ b/sys/net80211/ieee80211_freebsd.h
@@ -330,6 +330,8 @@ void	ieee80211_process_callback(struct ieee80211_node *, struct mbuf *, int);
 #define	NET80211_TAG_XMIT_PARAMS	1
 /* See below; this is after the bpf_params definition */
 
+#define	NET80211_TAG_RECV_PARAMS	2
+
 struct ieee80211com;
 int	ieee80211_parent_xmitpkt(struct ieee80211com *, struct mbuf *);
 int	ieee80211_vap_xmitpkt(struct ieee80211vap *, struct mbuf *);
@@ -618,6 +620,43 @@ int	ieee80211_add_xmit_params(struct mbuf *m,
 	    const struct ieee80211_bpf_params *);
 int	ieee80211_get_xmit_params(struct mbuf *m,
 	    struct ieee80211_bpf_params *);
+
+#define	IEEE80211_MAX_CHAINS		3
+#define	IEEE80211_MAX_EVM_PILOTS	6
+
+#define	IEEE80211_R_NF		0x0000001	/* global NF value valid */
+#define	IEEE80211_R_RSSI	0x0000002	/* global RSSI value valid */
+#define	IEEE80211_R_C_CHAIN	0x0000004	/* RX chain count valid */
+#define	IEEE80211_R_C_NF	0x0000008	/* per-chain NF value valid */
+#define	IEEE80211_R_C_RSSI	0x0000010	/* per-chain RSSI value valid */
+#define	IEEE80211_R_C_EVM	0x0000020	/* per-chain EVM valid */
+#define	IEEE80211_R_C_HT40	0x0000040	/* RX'ed packet is 40mhz, pilots 4,5 valid */
+#define	IEEE80211_R_FREQ	0x0000080	/* Freq value populated, MHz */
+#define	IEEE80211_R_IEEE	0x0000100	/* IEEE value populated */
+#define	IEEE80211_R_BAND	0x0000200	/* Frequency band populated */
+
+struct ieee80211_rx_stats {
+	uint32_t r_flags;		/* IEEE80211_R_* flags */
+	uint8_t c_chain;		/* number of RX chains involved */
+	int16_t	c_nf_ctl[IEEE80211_MAX_CHAINS];	/* per-chain NF */
+	int16_t	c_nf_ext[IEEE80211_MAX_CHAINS];	/* per-chain NF */
+	int16_t	c_rssi_ctl[IEEE80211_MAX_CHAINS];	/* per-chain RSSI */
+	int16_t	c_rssi_ext[IEEE80211_MAX_CHAINS];	/* per-chain RSSI */
+	uint8_t nf;			/* global NF */
+	uint8_t rssi;			/* global RSSI */
+	uint8_t evm[IEEE80211_MAX_CHAINS][IEEE80211_MAX_EVM_PILOTS];
+					/* per-chain, per-pilot EVM values */
+	uint16_t c_freq;
+	uint8_t c_ieee;
+};
+
+struct ieee80211_rx_params {
+	struct ieee80211_rx_stats params;
+};
+int	ieee80211_add_rx_params(struct mbuf *m,
+	    const struct ieee80211_rx_stats *rxs);
+int	ieee80211_get_rx_params(struct mbuf *m,
+	    struct ieee80211_rx_stats *rxs);
 #endif /* _KERNEL */
 
 /*
diff --git a/sys/net80211/ieee80211_input.c b/sys/net80211/ieee80211_input.c
index b757ae6..0b95520 100644
--- a/sys/net80211/ieee80211_input.c
+++ b/sys/net80211/ieee80211_input.c
@@ -86,10 +86,21 @@ int
 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
     struct ieee80211_rx_stats *rx)
 {
+	struct ieee80211_rx_stats rxs;
+
+	if (rx) {
+		memcpy(&rxs, rx, sizeof(*rx));
+	} else {
+		/* try to read from mbuf */
+		bzero(&rxs, sizeof(rxs));
+		ieee80211_get_rx_params(m, &rxs);
+	}
+
 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
-	ieee80211_process_mimo(ni, rx);
+	ieee80211_process_mimo(ni, &rxs);
+
 	//return ieee80211_input(ni, m, rx->rssi, rx->nf);
-	return ni->ni_vap->iv_input(ni, m, rx, rx->rssi, rx->nf);
+	return ni->ni_vap->iv_input(ni, m, &rxs, rxs.rssi, rxs.nf);
 }
 
 int
@@ -107,11 +118,20 @@ int
 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
     struct ieee80211_rx_stats *rx)
 {
+	struct ieee80211_rx_stats rxs;
 	struct ieee80211vap *vap;
 	int type = -1;
 
 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
 
+	if (rx) {
+		memcpy(&rxs, rx, sizeof(*rx));
+	} else {
+		/* try to read from mbuf */
+		bzero(&rxs, sizeof(rxs));
+		ieee80211_get_rx_params(m, &rxs);
+	}
+
 	/* XXX locking */
 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
 		struct ieee80211_node *ni;
@@ -143,7 +163,7 @@ ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
 			m = NULL;
 		}
 		ni = ieee80211_ref_node(vap->iv_bss);
-		type = ieee80211_input_mimo(ni, mcopy, rx);
+		type = ieee80211_input_mimo(ni, mcopy, &rxs);
 		ieee80211_free_node(ni);
 	}
 	if (m != NULL)			/* no vaps, reclaim mbuf */
diff --git a/sys/net80211/ieee80211_proto.h b/sys/net80211/ieee80211_proto.h
index 165431b..273e759 100644
--- a/sys/net80211/ieee80211_proto.h
+++ b/sys/net80211/ieee80211_proto.h
@@ -62,32 +62,6 @@ void	ieee80211_syncflag(struct ieee80211vap *, int flag);
 void	ieee80211_syncflag_ht(struct ieee80211vap *, int flag);
 void	ieee80211_syncflag_ext(struct ieee80211vap *, int flag);
 
-#define	IEEE80211_R_NF		0x0000001	/* global NF value valid */
-#define	IEEE80211_R_RSSI	0x0000002	/* global RSSI value valid */
-#define	IEEE80211_R_C_CHAIN	0x0000004	/* RX chain count valid */
-#define	IEEE80211_R_C_NF	0x0000008	/* per-chain NF value valid */
-#define	IEEE80211_R_C_RSSI	0x0000010	/* per-chain RSSI value valid */
-#define	IEEE80211_R_C_EVM	0x0000020	/* per-chain EVM valid */
-#define	IEEE80211_R_C_HT40	0x0000040	/* RX'ed packet is 40mhz, pilots 4,5 valid */
-#define	IEEE80211_R_FREQ	0x0000080	/* Freq value populated, MHz */
-#define	IEEE80211_R_IEEE	0x0000100	/* IEEE value populated */
-#define	IEEE80211_R_BAND	0x0000200	/* Frequency band populated */
-
-struct ieee80211_rx_stats {
-	uint32_t r_flags;		/* IEEE80211_R_* flags */
-	uint8_t c_chain;		/* number of RX chains involved */
-	int16_t	c_nf_ctl[IEEE80211_MAX_CHAINS];	/* per-chain NF */
-	int16_t	c_nf_ext[IEEE80211_MAX_CHAINS];	/* per-chain NF */
-	int16_t	c_rssi_ctl[IEEE80211_MAX_CHAINS];	/* per-chain RSSI */
-	int16_t	c_rssi_ext[IEEE80211_MAX_CHAINS];	/* per-chain RSSI */
-	uint8_t nf;			/* global NF */
-	uint8_t rssi;			/* global RSSI */
-	uint8_t evm[IEEE80211_MAX_CHAINS][IEEE80211_MAX_EVM_PILOTS];
-					/* per-chain, per-pilot EVM values */
-	uint16_t c_freq;
-	uint8_t c_ieee;
-};
-
 #define	ieee80211_input(ni, m, rssi, nf) \
 	((ni)->ni_vap->iv_input(ni, m, NULL, rssi, nf))
 int	ieee80211_input_all(struct ieee80211com *, struct mbuf *, int, int);