Merge branch 'net-in_interrupt-cleanup-and-fixes'

Thomas Gleixner says:

====================
net: in_interrupt() cleanup and fixes

in the discussion about preempt count consistency accross kernel configurations:

  https://lore.kernel.org/r/20200914204209.256266093@linutronix.de/

Linus clearly requested that code in drivers and libraries which changes
behaviour based on execution context should either be split up so that
e.g. task context invocations and BH invocations have different interfaces
or if that's not possible the context information has to be provided by the
caller which knows in which context it is executing.

This includes conditional locking, allocation mode (GFP_*) decisions and
avoidance of code paths which might sleep.

In the long run, usage of 'preemptible, in_*irq etc.' should be banned from
driver code completely.

This is the second version of the first batch of related changes. V1 can be
found here:

     https://lore.kernel.org/r/20200927194846.045411263@linutronix.de

Changes vs. V1:

  - Rebased to net-next

  - Fixed the half done rename sillyness in the ENIC patch.

  - Fixed the IONIC driver fallout.

  - Picked up the SFC fix from Edward and adjusted the GFP_KERNEL change
    accordingly.

  - Addressed the review comments vs. BCRFMAC.

  - Collected Reviewed/Acked-by tags as appropriate.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

14 files changed, 47 insertions, 44 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcdc.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcdc.c
index 2c95a08a5871..3984fd7d918e 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcdc.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcdc.c
@@ -397,9 +397,9 @@ brcmf_proto_bcdc_add_tdls_peer(struct brcmf_pub *drvr, int ifidx,
 }
 
 static void brcmf_proto_bcdc_rxreorder(struct brcmf_if *ifp,
-				       struct sk_buff *skb)
+				       struct sk_buff *skb, bool inirq)
 {
-	brcmf_fws_rxreorder(ifp, skb);
+	brcmf_fws_rxreorder(ifp, skb, inirq);
 }
 
 static void
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
index 318bd00bf94f..f9ebb98b0e3c 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c
@@ -74,7 +74,7 @@ static irqreturn_t brcmf_sdiod_oob_irqhandler(int irq, void *dev_id)
 		sdiodev->irq_en = false;
 	}
 
-	brcmf_sdio_isr(sdiodev->bus);
+	brcmf_sdio_isr(sdiodev->bus, true);
 
 	return IRQ_HANDLED;
 }
@@ -86,7 +86,7 @@ static void brcmf_sdiod_ib_irqhandler(struct sdio_func *func)
 
 	brcmf_dbg(INTR, "IB intr triggered\n");
 
-	brcmf_sdio_isr(sdiodev->bus);
+	brcmf_sdio_isr(sdiodev->bus, false);
 }
 
 /* dummy handler for SDIO function 2 interrupt */
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
index 623c0168da79..08f9d47f2e5c 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/bus.h
@@ -249,7 +249,8 @@ int brcmf_bus_reset(struct brcmf_bus *bus)
  */
 
 /* Receive frame for delivery to OS.  Callee disposes of rxp. */
-void brcmf_rx_frame(struct device *dev, struct sk_buff *rxp, bool handle_event);
+void brcmf_rx_frame(struct device *dev, struct sk_buff *rxp, bool handle_event,
+		    bool inirq);
 /* Receive async event packet from firmware. Callee disposes of rxp. */
 void brcmf_rx_event(struct device *dev, struct sk_buff *rxp);
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index aa9ced3c86fb..4ac1e4fb7812 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -395,7 +395,7 @@ void brcmf_txflowblock_if(struct brcmf_if *ifp,
 	spin_unlock_irqrestore(&ifp->netif_stop_lock, flags);
 }
 
-void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb)
+void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq)
 {
 	/* Most of Broadcom's firmwares send 802.11f ADD frame every time a new
 	 * STA connects to the AP interface. This is an obsoleted standard most
@@ -418,14 +418,15 @@ void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb)
 	ifp->ndev->stats.rx_packets++;
 
 	brcmf_dbg(DATA, "rx proto=0x%X\n", ntohs(skb->protocol));
-	if (in_interrupt())
+	if (inirq) {
 		netif_rx(skb);
-	else
+	} else {
 		/* If the receive is not processed inside an ISR,
 		 * the softirqd must be woken explicitly to service
 		 * the NET_RX_SOFTIRQ.  This is handled by netif_rx_ni().
 		 */
 		netif_rx_ni(skb);
+	}
 }
 
 void brcmf_netif_mon_rx(struct brcmf_if *ifp, struct sk_buff *skb)
@@ -474,7 +475,7 @@ void brcmf_netif_mon_rx(struct brcmf_if *ifp, struct sk_buff *skb)
 	skb->pkt_type = PACKET_OTHERHOST;
 	skb->protocol = htons(ETH_P_802_2);
 
-	brcmf_netif_rx(ifp, skb);
+	brcmf_netif_rx(ifp, skb, false);
 }
 
 static int brcmf_rx_hdrpull(struct brcmf_pub *drvr, struct sk_buff *skb,
@@ -496,7 +497,8 @@ static int brcmf_rx_hdrpull(struct brcmf_pub *drvr, struct sk_buff *skb,
 	return 0;
 }
 
-void brcmf_rx_frame(struct device *dev, struct sk_buff *skb, bool handle_event)
+void brcmf_rx_frame(struct device *dev, struct sk_buff *skb, bool handle_event,
+		    bool inirq)
 {
 	struct brcmf_if *ifp;
 	struct brcmf_bus *bus_if = dev_get_drvdata(dev);
@@ -508,14 +510,16 @@ void brcmf_rx_frame(struct device *dev, struct sk_buff *skb, bool handle_event)
 		return;
 
 	if (brcmf_proto_is_reorder_skb(skb)) {
-		brcmf_proto_rxreorder(ifp, skb);
+		brcmf_proto_rxreorder(ifp, skb, inirq);
 	} else {
 		/* Process special event packets */
-		if (handle_event)
-			brcmf_fweh_process_skb(ifp->drvr, skb,
-					       BCMILCP_SUBTYPE_VENDOR_LONG);
+		if (handle_event) {
+			gfp_t gfp = inirq ? GFP_ATOMIC : GFP_KERNEL;
 
-		brcmf_netif_rx(ifp, skb);
+			brcmf_fweh_process_skb(ifp->drvr, skb,
+					       BCMILCP_SUBTYPE_VENDOR_LONG, gfp);
+		}
+		brcmf_netif_rx(ifp, skb, inirq);
 	}
 }
 
@@ -530,7 +534,7 @@ void brcmf_rx_event(struct device *dev, struct sk_buff *skb)
 	if (brcmf_rx_hdrpull(drvr, skb, &ifp))
 		return;
 
-	brcmf_fweh_process_skb(ifp->drvr, skb, 0);
+	brcmf_fweh_process_skb(ifp->drvr, skb, 0, GFP_KERNEL);
 	brcmu_pkt_buf_free_skb(skb);
 }
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
index 33b2ab3b54b0..5767d665cee5 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.h
@@ -208,7 +208,7 @@ void brcmf_remove_interface(struct brcmf_if *ifp, bool rtnl_locked);
 void brcmf_txflowblock_if(struct brcmf_if *ifp,
 			  enum brcmf_netif_stop_reason reason, bool state);
 void brcmf_txfinalize(struct brcmf_if *ifp, struct sk_buff *txp, bool success);
-void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb);
+void brcmf_netif_rx(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq);
 void brcmf_netif_mon_rx(struct brcmf_if *ifp, struct sk_buff *skb);
 void brcmf_net_detach(struct net_device *ndev, bool rtnl_locked);
 int brcmf_net_mon_attach(struct brcmf_if *ifp);
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c
index 3bdbb285b3aa..c847062dd393 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c
@@ -388,12 +388,11 @@ int brcmf_fweh_activate_events(struct brcmf_if *ifp)
  */
 void brcmf_fweh_process_event(struct brcmf_pub *drvr,
 			      struct brcmf_event *event_packet,
-			      u32 packet_len)
+			      u32 packet_len, gfp_t gfp)
 {
 	enum brcmf_fweh_event_code code;
 	struct brcmf_fweh_info *fweh = &drvr->fweh;
 	struct brcmf_fweh_queue_item *event;
-	gfp_t alloc_flag = GFP_KERNEL;
 	void *data;
 	u32 datalen;
 
@@ -412,10 +411,7 @@ void brcmf_fweh_process_event(struct brcmf_pub *drvr,
 	    datalen + sizeof(*event_packet) > packet_len)
 		return;
 
-	if (in_interrupt())
-		alloc_flag = GFP_ATOMIC;
-
-	event = kzalloc(sizeof(*event) + datalen, alloc_flag);
+	event = kzalloc(sizeof(*event) + datalen, gfp);
 	if (!event)
 		return;
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
index a82f51bc1e69..48414e8b9389 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.h
@@ -319,11 +319,12 @@ void brcmf_fweh_unregister(struct brcmf_pub *drvr,
 int brcmf_fweh_activate_events(struct brcmf_if *ifp);
 void brcmf_fweh_process_event(struct brcmf_pub *drvr,
 			      struct brcmf_event *event_packet,
-			      u32 packet_len);
+			      u32 packet_len, gfp_t gfp);
 void brcmf_fweh_p2pdev_setup(struct brcmf_if *ifp, bool ongoing);
 
 static inline void brcmf_fweh_process_skb(struct brcmf_pub *drvr,
-					  struct sk_buff *skb, u16 stype)
+					  struct sk_buff *skb, u16 stype,
+					  gfp_t gfp)
 {
 	struct brcmf_event *event_packet;
 	u16 subtype, usr_stype;
@@ -354,7 +355,7 @@ static inline void brcmf_fweh_process_skb(struct brcmf_pub *drvr,
 	if (usr_stype != BCMILCP_BCM_SUBTYPE_EVENT)
 		return;
 
-	brcmf_fweh_process_event(drvr, event_packet, skb->len + ETH_HLEN);
+	brcmf_fweh_process_event(drvr, event_packet, skb->len + ETH_HLEN, gfp);
 }
 
 #endif /* FWEH_H_ */
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
index 775e0612fa17..437e83ea8902 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.c
@@ -1664,7 +1664,7 @@ static void brcmf_rxreorder_get_skb_list(struct brcmf_ampdu_rx_reorder *rfi,
 	rfi->pend_pkts -= skb_queue_len(skb_list);
 }
 
-void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt)
+void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt, bool inirq)
 {
 	struct brcmf_pub *drvr = ifp->drvr;
 	u8 *reorder_data;
@@ -1682,7 +1682,7 @@ void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt)
 	/* validate flags and flow id */
 	if (flags == 0xFF) {
 		bphy_err(drvr, "invalid flags...so ignore this packet\n");
-		brcmf_netif_rx(ifp, pkt);
+		brcmf_netif_rx(ifp, pkt, inirq);
 		return;
 	}
 
@@ -1694,7 +1694,7 @@ void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt)
 		if (rfi == NULL) {
 			brcmf_dbg(INFO, "received flags to cleanup, but no flow (%d) yet\n",
 				  flow_id);
-			brcmf_netif_rx(ifp, pkt);
+			brcmf_netif_rx(ifp, pkt, inirq);
 			return;
 		}
 
@@ -1719,7 +1719,7 @@ void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt)
 		rfi = kzalloc(buf_size, GFP_ATOMIC);
 		if (rfi == NULL) {
 			bphy_err(drvr, "failed to alloc buffer\n");
-			brcmf_netif_rx(ifp, pkt);
+			brcmf_netif_rx(ifp, pkt, inirq);
 			return;
 		}
 
@@ -1833,7 +1833,7 @@ void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *pkt)
 netif_rx:
 	skb_queue_walk_safe(&reorder_list, pkt, pnext) {
 		__skb_unlink(pkt, &reorder_list);
-		brcmf_netif_rx(ifp, pkt);
+		brcmf_netif_rx(ifp, pkt, inirq);
 	}
 }
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.h
index b16a9d1c0508..50e424b5880d 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwsignal.h
@@ -42,6 +42,6 @@ void brcmf_fws_add_interface(struct brcmf_if *ifp);
 void brcmf_fws_del_interface(struct brcmf_if *ifp);
 void brcmf_fws_bustxfail(struct brcmf_fws_info *fws, struct sk_buff *skb);
 void brcmf_fws_bus_blocked(struct brcmf_pub *drvr, bool flow_blocked);
-void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb);
+void brcmf_fws_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq);
 
 #endif /* FWSIGNAL_H_ */
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
index bfddb851e386..7c8e08ee8f0f 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/msgbuf.c
@@ -536,7 +536,8 @@ static int brcmf_msgbuf_hdrpull(struct brcmf_pub *drvr, bool do_fws,
 	return -ENODEV;
 }
 
-static void brcmf_msgbuf_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb)
+static void brcmf_msgbuf_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb,
+				   bool inirq)
 {
 }
 
@@ -1128,7 +1129,7 @@ static void brcmf_msgbuf_process_event(struct brcmf_msgbuf *msgbuf, void *buf)
 
 	skb->protocol = eth_type_trans(skb, ifp->ndev);
 
-	brcmf_fweh_process_skb(ifp->drvr, skb, 0);
+	brcmf_fweh_process_skb(ifp->drvr, skb, 0, GFP_KERNEL);
 
 exit:
 	brcmu_pkt_buf_free_skb(skb);
@@ -1190,7 +1191,7 @@ brcmf_msgbuf_process_rx_complete(struct brcmf_msgbuf *msgbuf, void *buf)
 	}
 
 	skb->protocol = eth_type_trans(skb, ifp->ndev);
-	brcmf_netif_rx(ifp, skb);
+	brcmf_netif_rx(ifp, skb, false);
 }
 
 static void brcmf_msgbuf_process_gen_status(struct brcmf_msgbuf *msgbuf,
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/proto.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/proto.h
index bd08d3aaa8f4..f4a79e217da5 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/proto.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/proto.h
@@ -32,7 +32,7 @@ struct brcmf_proto {
 			    u8 peer[ETH_ALEN]);
 	void (*add_tdls_peer)(struct brcmf_pub *drvr, int ifidx,
 			      u8 peer[ETH_ALEN]);
-	void (*rxreorder)(struct brcmf_if *ifp, struct sk_buff *skb);
+	void (*rxreorder)(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq);
 	void (*add_if)(struct brcmf_if *ifp);
 	void (*del_if)(struct brcmf_if *ifp);
 	void (*reset_if)(struct brcmf_if *ifp);
@@ -109,9 +109,9 @@ static inline bool brcmf_proto_is_reorder_skb(struct sk_buff *skb)
 }
 
 static inline void
-brcmf_proto_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb)
+brcmf_proto_rxreorder(struct brcmf_if *ifp, struct sk_buff *skb, bool inirq)
 {
-	ifp->drvr->proto->rxreorder(ifp, skb);
+	ifp->drvr->proto->rxreorder(ifp, skb, inirq);
 }
 
 static inline void
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
index d4989e0cd7be..99987a789e7e 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
@@ -1704,7 +1704,7 @@ static u8 brcmf_sdio_rxglom(struct brcmf_sdio *bus, u8 rxseq)
 				brcmf_rx_event(bus->sdiodev->dev, pfirst);
 			else
 				brcmf_rx_frame(bus->sdiodev->dev, pfirst,
-					       false);
+					       false, false);
 			bus->sdcnt.rxglompkts++;
 		}
 
@@ -2038,7 +2038,7 @@ static uint brcmf_sdio_readframes(struct brcmf_sdio *bus, uint maxframes)
 			brcmf_rx_event(bus->sdiodev->dev, pkt);
 		else
 			brcmf_rx_frame(bus->sdiodev->dev, pkt,
-				       false);
+				       false, false);
 
 		/* prepare the descriptor for the next read */
 		rd->len = rd->len_nxtfrm << 4;
@@ -3625,7 +3625,7 @@ void brcmf_sdio_trigger_dpc(struct brcmf_sdio *bus)
 	}
 }
 
-void brcmf_sdio_isr(struct brcmf_sdio *bus)
+void brcmf_sdio_isr(struct brcmf_sdio *bus, bool in_isr)
 {
 	brcmf_dbg(TRACE, "Enter\n");
 
@@ -3636,7 +3636,7 @@ void brcmf_sdio_isr(struct brcmf_sdio *bus)
 
 	/* Count the interrupt call */
 	bus->sdcnt.intrcount++;
-	if (in_interrupt())
+	if (in_isr)
 		atomic_set(&bus->ipend, 1);
 	else
 		if (brcmf_sdio_intr_rstatus(bus)) {
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.h
index 12108927fb50..15d2c02fa3ec 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.h
@@ -372,7 +372,7 @@ int brcmf_sdiod_remove(struct brcmf_sdio_dev *sdiodev);
 
 struct brcmf_sdio *brcmf_sdio_probe(struct brcmf_sdio_dev *sdiodev);
 void brcmf_sdio_remove(struct brcmf_sdio *bus);
-void brcmf_sdio_isr(struct brcmf_sdio *bus);
+void brcmf_sdio_isr(struct brcmf_sdio *bus, bool in_isr);
 
 void brcmf_sdio_wd_timer(struct brcmf_sdio *bus, bool active);
 void brcmf_sdio_wowl_config(struct device *dev, bool enabled);
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/usb.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/usb.c
index 6f67fefe4b58..586f4dfc638b 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/usb.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/usb.c
@@ -532,7 +532,7 @@ static void brcmf_usb_rx_complete(struct urb *urb)
 	if (devinfo->bus_pub.state == BRCMFMAC_USB_STATE_UP ||
 	    devinfo->bus_pub.state == BRCMFMAC_USB_STATE_SLEEP) {
 		skb_put(skb, urb->actual_length);
-		brcmf_rx_frame(devinfo->dev, skb, true);
+		brcmf_rx_frame(devinfo->dev, skb, true, true);
 		brcmf_usb_rx_refill(devinfo, req);
 		usb_mark_last_busy(urb->dev);
 	} else {