Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Fix verifier memory corruption and other bugs in BPF layer, from
    Alexei Starovoitov.

 2) Add a conservative fix for doing BPF properly in the BPF classifier
    of the packet scheduler on ingress.  Also from Alexei.

 3) The SKB scrubber should not clear out the packet MARK and security
    label, from Herbert Xu.

 4) Fix oops on rmmod in stmmac driver, from Bryan O'Donoghue.

 5) Pause handling is not correct in the stmmac driver because it
    doesn't take into consideration the RX and TX fifo sizes.  From
    Vince Bridgers.

 6) Failure path missing unlock in FOU driver, from Wang Cong.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
  net: dsa: use DEVICE_ATTR_RW to declare temp1_max
  netns: remove BUG_ONs from net_generic()
  IB/ipoib: Fix ndo_get_iflink
  sfc: Fix memcpy() with const destination compiler warning.
  altera tse: Fix network-delays and -retransmissions after high throughput.
  net: remove unused 'dev' argument from netif_needs_gso()
  act_mirred: Fix bogus header when redirecting from VLAN
  inet_diag: fix access to tcp cc information
  tcp: tcp_get_info() should fetch socket fields once
  net: dsa: mv88e6xxx: Add missing initialization in mv88e6xxx_set_port_state()
  skbuff: Do not scrub skb mark within the same name space
  Revert "net: Reset secmark when scrubbing packet"
  bpf: fix two bugs in verification logic when accessing 'ctx' pointer
  bpf: fix bpf helpers to use skb->mac_header relative offsets
  stmmac: Configure Flow Control to work correctly based on rxfifo size
  stmmac: Enable unicast pause frame detect in GMAC Register 6
  stmmac: Read tx-fifo-depth and rx-fifo-depth from the devicetree
  stmmac: Add defines and documentation for enabling flow control
  stmmac: Add properties for transmit and receive fifo sizes
  stmmac: fix oops on rmmod after assigning ip addr
  ...

2 files changed, 56 insertions, 90 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
index 4085c4b31047..355d5fea5be9 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
@@ -531,20 +531,8 @@ struct bnx2x_fastpath {
 	struct napi_struct	napi;
 
 #ifdef CONFIG_NET_RX_BUSY_POLL
-	unsigned int state;
-#define BNX2X_FP_STATE_IDLE		      0
-#define BNX2X_FP_STATE_NAPI		(1 << 0)    /* NAPI owns this FP */
-#define BNX2X_FP_STATE_POLL		(1 << 1)    /* poll owns this FP */
-#define BNX2X_FP_STATE_DISABLED		(1 << 2)
-#define BNX2X_FP_STATE_NAPI_YIELD	(1 << 3)    /* NAPI yielded this FP */
-#define BNX2X_FP_STATE_POLL_YIELD	(1 << 4)    /* poll yielded this FP */
-#define BNX2X_FP_OWNED	(BNX2X_FP_STATE_NAPI | BNX2X_FP_STATE_POLL)
-#define BNX2X_FP_YIELD	(BNX2X_FP_STATE_NAPI_YIELD | BNX2X_FP_STATE_POLL_YIELD)
-#define BNX2X_FP_LOCKED	(BNX2X_FP_OWNED | BNX2X_FP_STATE_DISABLED)
-#define BNX2X_FP_USER_PEND (BNX2X_FP_STATE_POLL | BNX2X_FP_STATE_POLL_YIELD)
-	/* protect state */
-	spinlock_t lock;
-#endif /* CONFIG_NET_RX_BUSY_POLL */
+	unsigned long		busy_poll_state;
+#endif
 
 	union host_hc_status_block	status_blk;
 	/* chip independent shortcuts into sb structure */
@@ -619,104 +607,83 @@ struct bnx2x_fastpath {
 #define bnx2x_fp_qstats(bp, fp)	(&((bp)->fp_stats[(fp)->index].eth_q_stats))
 
 #ifdef CONFIG_NET_RX_BUSY_POLL
-static inline void bnx2x_fp_init_lock(struct bnx2x_fastpath *fp)
+
+enum bnx2x_fp_state {
+	BNX2X_STATE_FP_NAPI	= BIT(0), /* NAPI handler owns the queue */
+
+	BNX2X_STATE_FP_NAPI_REQ_BIT = 1, /* NAPI would like to own the queue */
+	BNX2X_STATE_FP_NAPI_REQ = BIT(1),
+
+	BNX2X_STATE_FP_POLL_BIT = 2,
+	BNX2X_STATE_FP_POLL     = BIT(2), /* busy_poll owns the queue */
+
+	BNX2X_STATE_FP_DISABLE_BIT = 3, /* queue is dismantled */
+};
+
+static inline void bnx2x_fp_busy_poll_init(struct bnx2x_fastpath *fp)
 {
-	spin_lock_init(&fp->lock);
-	fp->state = BNX2X_FP_STATE_IDLE;
+	WRITE_ONCE(fp->busy_poll_state, 0);
 }
 
 /* called from the device poll routine to get ownership of a FP */
 static inline bool bnx2x_fp_lock_napi(struct bnx2x_fastpath *fp)
 {
-	bool rc = true;
-
-	spin_lock_bh(&fp->lock);
-	if (fp->state & BNX2X_FP_LOCKED) {
-		WARN_ON(fp->state & BNX2X_FP_STATE_NAPI);
-		fp->state |= BNX2X_FP_STATE_NAPI_YIELD;
-		rc = false;
-	} else {
-		/* we don't care if someone yielded */
-		fp->state = BNX2X_FP_STATE_NAPI;
+	unsigned long prev, old = READ_ONCE(fp->busy_poll_state);
+
+	while (1) {
+		switch (old) {
+		case BNX2X_STATE_FP_POLL:
+			/* make sure bnx2x_fp_lock_poll() wont starve us */
+			set_bit(BNX2X_STATE_FP_NAPI_REQ_BIT,
+				&fp->busy_poll_state);
+			/* fallthrough */
+		case BNX2X_STATE_FP_POLL | BNX2X_STATE_FP_NAPI_REQ:
+			return false;
+		default:
+			break;
+		}
+		prev = cmpxchg(&fp->busy_poll_state, old, BNX2X_STATE_FP_NAPI);
+		if (unlikely(prev != old)) {
+			old = prev;
+			continue;
+		}
+		return true;
 	}
-	spin_unlock_bh(&fp->lock);
-	return rc;
 }
 
-/* returns true is someone tried to get the FP while napi had it */
-static inline bool bnx2x_fp_unlock_napi(struct bnx2x_fastpath *fp)
+static inline void bnx2x_fp_unlock_napi(struct bnx2x_fastpath *fp)
 {
-	bool rc = false;
-
-	spin_lock_bh(&fp->lock);
-	WARN_ON(fp->state &
-		(BNX2X_FP_STATE_POLL | BNX2X_FP_STATE_NAPI_YIELD));
-
-	if (fp->state & BNX2X_FP_STATE_POLL_YIELD)
-		rc = true;
-
-	/* state ==> idle, unless currently disabled */
-	fp->state &= BNX2X_FP_STATE_DISABLED;
-	spin_unlock_bh(&fp->lock);
-	return rc;
+	smp_wmb();
+	fp->busy_poll_state = 0;
 }
 
 /* called from bnx2x_low_latency_poll() */
 static inline bool bnx2x_fp_lock_poll(struct bnx2x_fastpath *fp)
 {
-	bool rc = true;
-
-	spin_lock_bh(&fp->lock);
-	if ((fp->state & BNX2X_FP_LOCKED)) {
-		fp->state |= BNX2X_FP_STATE_POLL_YIELD;
-		rc = false;
-	} else {
-		/* preserve yield marks */
-		fp->state |= BNX2X_FP_STATE_POLL;
-	}
-	spin_unlock_bh(&fp->lock);
-	return rc;
+	return cmpxchg(&fp->busy_poll_state, 0, BNX2X_STATE_FP_POLL) == 0;
 }
 
-/* returns true if someone tried to get the FP while it was locked */
-static inline bool bnx2x_fp_unlock_poll(struct bnx2x_fastpath *fp)
+static inline void bnx2x_fp_unlock_poll(struct bnx2x_fastpath *fp)
 {
-	bool rc = false;
-
-	spin_lock_bh(&fp->lock);
-	WARN_ON(fp->state & BNX2X_FP_STATE_NAPI);
-
-	if (fp->state & BNX2X_FP_STATE_POLL_YIELD)
-		rc = true;
-
-	/* state ==> idle, unless currently disabled */
-	fp->state &= BNX2X_FP_STATE_DISABLED;
-	spin_unlock_bh(&fp->lock);
-	return rc;
+	smp_mb__before_atomic();
+	clear_bit(BNX2X_STATE_FP_POLL_BIT, &fp->busy_poll_state);
 }
 
-/* true if a socket is polling, even if it did not get the lock */
+/* true if a socket is polling */
 static inline bool bnx2x_fp_ll_polling(struct bnx2x_fastpath *fp)
 {
-	WARN_ON(!(fp->state & BNX2X_FP_OWNED));
-	return fp->state & BNX2X_FP_USER_PEND;
+	return READ_ONCE(fp->busy_poll_state) & BNX2X_STATE_FP_POLL;
 }
 
 /* false if fp is currently owned */
 static inline bool bnx2x_fp_ll_disable(struct bnx2x_fastpath *fp)
 {
-	int rc = true;
-
-	spin_lock_bh(&fp->lock);
-	if (fp->state & BNX2X_FP_OWNED)
-		rc = false;
-	fp->state |= BNX2X_FP_STATE_DISABLED;
-	spin_unlock_bh(&fp->lock);
+	set_bit(BNX2X_STATE_FP_DISABLE_BIT, &fp->busy_poll_state);
+	return !bnx2x_fp_ll_polling(fp);
 
-	return rc;
 }
 #else
-static inline void bnx2x_fp_init_lock(struct bnx2x_fastpath *fp)
+static inline void bnx2x_fp_busy_poll_init(struct bnx2x_fastpath *fp)
 {
 }
 
@@ -725,9 +692,8 @@ static inline bool bnx2x_fp_lock_napi(struct bnx2x_fastpath *fp)
 	return true;
 }
 
-static inline bool bnx2x_fp_unlock_napi(struct bnx2x_fastpath *fp)
+static inline void bnx2x_fp_unlock_napi(struct bnx2x_fastpath *fp)
 {
-	return false;
 }
 
 static inline bool bnx2x_fp_lock_poll(struct bnx2x_fastpath *fp)
@@ -735,9 +701,8 @@ static inline bool bnx2x_fp_lock_poll(struct bnx2x_fastpath *fp)
 	return false;
 }
 
-static inline bool bnx2x_fp_unlock_poll(struct bnx2x_fastpath *fp)
+static inline void bnx2x_fp_unlock_poll(struct bnx2x_fastpath *fp)
 {
-	return false;
 }
 
 static inline bool bnx2x_fp_ll_polling(struct bnx2x_fastpath *fp)
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 0a9faa134a9a..2f63467bce46 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -1849,7 +1849,7 @@ static void bnx2x_napi_enable_cnic(struct bnx2x *bp)
 	int i;
 
 	for_each_rx_queue_cnic(bp, i) {
-		bnx2x_fp_init_lock(&bp->fp[i]);
+		bnx2x_fp_busy_poll_init(&bp->fp[i]);
 		napi_enable(&bnx2x_fp(bp, i, napi));
 	}
 }
@@ -1859,7 +1859,7 @@ static void bnx2x_napi_enable(struct bnx2x *bp)
 	int i;
 
 	for_each_eth_queue(bp, i) {
-		bnx2x_fp_init_lock(&bp->fp[i]);
+		bnx2x_fp_busy_poll_init(&bp->fp[i]);
 		napi_enable(&bnx2x_fp(bp, i, napi));
 	}
 }
@@ -3191,9 +3191,10 @@ static int bnx2x_poll(struct napi_struct *napi, int budget)
 			}
 		}
 
+		bnx2x_fp_unlock_napi(fp);
+
 		/* Fall out from the NAPI loop if needed */
-		if (!bnx2x_fp_unlock_napi(fp) &&
-		    !(bnx2x_has_rx_work(fp) || bnx2x_has_tx_work(fp))) {
+		if (!(bnx2x_has_rx_work(fp) || bnx2x_has_tx_work(fp))) {
 
 			/* No need to update SB for FCoE L2 ring as long as
 			 * it's connected to the default SB and the SB