cnic, bnx2x: Add CNIC_DRV_STATE_HANDLES_IRQ to ethdev->drv_state

In INTA mode, cnic and bnx2x share the same IRQ.  During chip reset,
for example, cnic will stop servicing IRQs after it has shutdown the
cnic hardware resources.  However, the shared IRQ is still active as
bnx2x needs to finish the reset.  There is a window when bnx2x does
not know that cnic is no longer handling IRQ and things don't always
work properly.

Add a flag to tell bnx2x that cnic is handling IRQ.  The flag is set
before the first cnic IRQ is expected and cleared when no more cnic
IRQs are expected, so there should be no race conditions.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Ariel Elior <ariele@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 11 insertions, 8 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
index ac00ddcd32fa..c4daee1b7286 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
@@ -1875,14 +1875,12 @@ irqreturn_t bnx2x_interrupt(int irq, void *dev_instance)
                 if (status & (mask | 0x1)) {
                         struct cnic_ops *c_ops = NULL;
 
-                        if (likely(bp->state == BNX2X_STATE_OPEN)) {
-                                rcu_read_lock();
-                                c_ops = rcu_dereference(bp->cnic_ops);
-                                if (c_ops)
-                                        c_ops->cnic_handler(bp->cnic_data,
-                                                            NULL);
-                                rcu_read_unlock();
-                        }
+                        rcu_read_lock();
+                        c_ops = rcu_dereference(bp->cnic_ops);
+                        if (c_ops && (bp->cnic_eth_dev.drv_state &
+                                      CNIC_DRV_STATE_HANDLES_IRQ))
+                                c_ops->cnic_handler(bp->cnic_data, NULL);
+                        rcu_read_unlock();
 
                         status &= ~mask;
                 }
diff --git a/drivers/net/ethernet/broadcom/cnic.c b/drivers/net/ethernet/broadcom/cnic.c
index df8c30d1a52c..1c4dadc7ebbb 100644
--- a/drivers/net/ethernet/broadcom/cnic.c
+++ b/drivers/net/ethernet/broadcom/cnic.c
@@ -4816,6 +4816,8 @@ static int cnic_start_bnx2_hw(struct cnic_dev *dev)
                 return err;
         }
 
+        ethdev->drv_state |= CNIC_DRV_STATE_HANDLES_IRQ;
+
         return 0;
 }
 
@@ -5136,6 +5138,7 @@ static int cnic_start_bnx2x_hw(struct cnic_dev *dev)
         if (ret)
                 return ret;
 
+        ethdev->drv_state |= CNIC_DRV_STATE_HANDLES_IRQ;
         return 0;
 }
 
@@ -5387,6 +5390,7 @@ static void cnic_stop_hw(struct cnic_dev *dev)
                 }
                 cnic_shutdown_rings(dev);
                 cp->stop_cm(dev);
+                cp->ethdev->drv_state &= ~CNIC_DRV_STATE_HANDLES_IRQ;
                 clear_bit(CNIC_F_CNIC_UP, &dev->flags);
                 RCU_INIT_POINTER(cp->ulp_ops[CNIC_ULP_L4], NULL);
                 synchronize_rcu();
diff --git a/drivers/net/ethernet/broadcom/cnic_if.h b/drivers/net/ethernet/broadcom/cnic_if.h
index 2a35436f9095..0c9367a0f57d 100644
--- a/drivers/net/ethernet/broadcom/cnic_if.h
+++ b/drivers/net/ethernet/broadcom/cnic_if.h
@@ -179,6 +179,7 @@ struct cnic_eth_dev {
 #define CNIC_DRV_STATE_NO_ISCSI_OOO     0x00000004
 #define CNIC_DRV_STATE_NO_ISCSI         0x00000008
 #define CNIC_DRV_STATE_NO_FCOE          0x00000010
+#define CNIC_DRV_STATE_HANDLES_IRQ      0x00000020
         u32             chip_id;
         u32             max_kwqe_pending;
         struct pci_dev  *pdev;