brcmfmac: Fix msgbuf flow control.

Msgbuf flow control was using a function to flow off and on which
was not supported without proptx enabled. Also flow control needs
to be handled per ifidx.

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Daniel (Deognyoun) Kim <dekim@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 62 insertions, 8 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/dhd.h b/drivers/net/wireless/brcm80211/brcmfmac/dhd.h
index 1825f736fd45..5e4317dbc2b0 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/dhd.h
+++ b/drivers/net/wireless/brcm80211/brcmfmac/dhd.h
@@ -121,12 +121,12 @@ struct brcmf_fws_mac_descriptor;
  *
  * @BRCMF_NETIF_STOP_REASON_FWS_FC:
  *      netif stopped due to firmware signalling flow control.
- * @BRCMF_NETIF_STOP_REASON_BLOCK_BUS:
- *      netif stopped due to bus blocking.
+ * @BRCMF_NETIF_STOP_REASON_FLOW:
+ *      netif stopped due to flowring full.
  */
 enum brcmf_netif_stop_reason {
         BRCMF_NETIF_STOP_REASON_FWS_FC = 1,
-        BRCMF_NETIF_STOP_REASON_BLOCK_BUS = 2
+        BRCMF_NETIF_STOP_REASON_FLOW = 2
 };
 
 /**
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/flowring.c b/drivers/net/wireless/brcm80211/brcmfmac/flowring.c
index 26cbb7c4ec4c..07009046fda5 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/flowring.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/flowring.c
@@ -158,6 +158,51 @@ u8 brcmf_flowring_tid(struct brcmf_flowring *flow, u8 flowid)
 }
 
 
+static void brcmf_flowring_block(struct brcmf_flowring *flow, u8 flowid,
+                                 bool blocked)
+{
+        struct brcmf_flowring_ring *ring;
+        struct brcmf_bus *bus_if;
+        struct brcmf_pub *drvr;
+        struct brcmf_if *ifp;
+        bool currently_blocked;
+        int i;
+        u8 ifidx;
+        unsigned long flags;
+
+        spin_lock_irqsave(&flow->block_lock, flags);
+
+        ring = flow->rings[flowid];
+        ifidx = brcmf_flowring_ifidx_get(flow, flowid);
+
+        currently_blocked = false;
+        for (i = 0; i < flow->nrofrings; i++) {
+                if (flow->rings[i]) {
+                        ring = flow->rings[i];
+                        if ((ring->status == RING_OPEN) &&
+                            (brcmf_flowring_ifidx_get(flow, i) == ifidx)) {
+                                if (ring->blocked) {
+                                        currently_blocked = true;
+                                        break;
+                                }
+                        }
+                }
+        }
+        ring->blocked = blocked;
+        if (currently_blocked == blocked) {
+                spin_unlock_irqrestore(&flow->block_lock, flags);
+                return;
+        }
+
+        bus_if = dev_get_drvdata(flow->dev);
+        drvr = bus_if->drvr;
+        ifp = drvr->iflist[ifidx];
+        brcmf_txflowblock_if(ifp, BRCMF_NETIF_STOP_REASON_FLOW, blocked);
+
+        spin_unlock_irqrestore(&flow->block_lock, flags);
+}
+
+
 void brcmf_flowring_delete(struct brcmf_flowring *flow, u8 flowid)
 {
         struct brcmf_flowring_ring *ring;
@@ -167,6 +212,7 @@ void brcmf_flowring_delete(struct brcmf_flowring *flow, u8 flowid)
         ring = flow->rings[flowid];
         if (!ring)
                 return;
+        brcmf_flowring_block(flow, flowid, false);
         hash_idx = ring->hash_id;
         flow->hash[hash_idx].ifidx = BRCMF_FLOWRING_INVALID_IFIDX;
         memset(flow->hash[hash_idx].mac, 0, ETH_ALEN);
@@ -193,9 +239,16 @@ void brcmf_flowring_enqueue(struct brcmf_flowring *flow, u8 flowid,
 
         if (!ring->blocked &&
             (skb_queue_len(&ring->skblist) > BRCMF_FLOWRING_HIGH)) {
-                brcmf_txflowblock(flow->dev, true);
+                brcmf_flowring_block(flow, flowid, true);
                 brcmf_dbg(MSGBUF, "Flowcontrol: BLOCK for ring %d\n", flowid);
-                ring->blocked = 1;
+                /* To prevent (work around) possible race condition, check
+                 * queue len again. It is also possible to use locking to
+                 * protect, but that is undesirable for every enqueue and
+                 * dequeue. This simple check will solve a possible race
+                 * condition if it occurs.
+                 */
+                if (skb_queue_len(&ring->skblist) < BRCMF_FLOWRING_LOW)
+                        brcmf_flowring_block(flow, flowid, false);
         }
 }
 
@@ -213,9 +266,8 @@ struct sk_buff *brcmf_flowring_dequeue(struct brcmf_flowring *flow, u8 flowid)
 
         if (ring->blocked &&
             (skb_queue_len(&ring->skblist) < BRCMF_FLOWRING_LOW)) {
-                brcmf_txflowblock(flow->dev, false);
+                brcmf_flowring_block(flow, flowid, false);
                 brcmf_dbg(MSGBUF, "Flowcontrol: OPEN for ring %d\n", flowid);
-                ring->blocked = 0;
         }
 
         return skb;
@@ -283,6 +335,7 @@ struct brcmf_flowring *brcmf_flowring_attach(struct device *dev, u16 nrofrings)
         if (flow) {
                 flow->dev = dev;
                 flow->nrofrings = nrofrings;
+                spin_lock_init(&flow->block_lock);
                 for (i = 0; i < ARRAY_SIZE(flow->addr_mode); i++)
                         flow->addr_mode[i] = ADDR_INDIRECT;
                 for (i = 0; i < ARRAY_SIZE(flow->hash); i++)
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/flowring.h b/drivers/net/wireless/brcm80211/brcmfmac/flowring.h
index 677f4b8065f6..cb9644ca6ece 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/flowring.h
+++ b/drivers/net/wireless/brcm80211/brcmfmac/flowring.h
@@ -35,7 +35,7 @@ enum ring_status {
 
 struct brcmf_flowring_ring {
         u8 hash_id;
-        u8 blocked;
+        bool blocked;
         enum ring_status status;
         struct sk_buff_head skblist;
 };
@@ -44,6 +44,7 @@ struct brcmf_flowring {
         struct device *dev;
         struct brcmf_flowring_hash hash[BRCMF_FLOWRING_HASHSIZE];
         struct brcmf_flowring_ring **rings;
+        spinlock_t block_lock;
         enum proto_addr_mode addr_mode[BRCMF_MAX_IFS];
         u16 nrofrings;
 };