Do not allocate multicast array memory in multicast filter

configuration function. For failed memory allocations, em(4)/lem(4)
called panic(9) which is not acceptable on production box.
igb(4)/ixgb(4)/ix(4) allocated the required memory in stack which
consumed 768 bytes of stack memory which looks too big.

To address these issues, allocate multicast array memory in device
attach time and make multicast configuration success under any
conditions. This change also removes the excessive use of memory in
stack.

Reviewed by:	jfv

2 files changed, 18 insertions, 1 deletions

diff --git a/sys/dev/ixgbe/ixgbe.c b/sys/dev/ixgbe/ixgbe.c
index e7ecff8..37b98df 100644
--- a/sys/dev/ixgbe/ixgbe.c
+++ b/sys/dev/ixgbe/ixgbe.c
@@ -524,6 +524,15 @@ ixgbe_attach(device_t dev)
 		goto err_out;
 	}
 
+	/* Allocate multicast array memory. */
+	adapter->mta = malloc(sizeof(u8) * IXGBE_ETH_LENGTH_OF_ADDRESS *
+	    MAX_NUM_MULTICAST_ADDRESSES, M_DEVBUF, M_NOWAIT);
+	if (adapter->mta == NULL) {
+		device_printf(dev, "Can not allocate multicast setup array\n");
+		error = ENOMEM;
+		goto err_late;
+	}
+
 	/* Initialize the shared code */
 	error = ixgbe_init_shared_code(hw);
 	if (error == IXGBE_ERR_SFP_NOT_PRESENT) {
@@ -636,6 +645,7 @@ err_out:
 	if (adapter->ifp != NULL)
 		if_free(adapter->ifp);
 	ixgbe_free_pci_resources(adapter);
+	free(adapter->mta, M_DEVBUF);
 	return (error);
 
 }
@@ -706,6 +716,7 @@ ixgbe_detach(device_t dev)
 
 	ixgbe_free_transmit_structures(adapter);
 	ixgbe_free_receive_structures(adapter);
+	free(adapter->mta, M_DEVBUF);
 
 	IXGBE_CORE_LOCK_DESTROY(adapter);
 	return (0);
@@ -1808,7 +1819,7 @@ static void
 ixgbe_set_multi(struct adapter *adapter)
 {
 	u32	fctrl;
-	u8	mta[MAX_NUM_MULTICAST_ADDRESSES * IXGBE_ETH_LENGTH_OF_ADDRESS];
+	u8	*mta;
 	u8	*update_ptr;
 	struct	ifmultiaddr *ifma;
 	int	mcnt = 0;
@@ -1816,6 +1827,10 @@ ixgbe_set_multi(struct adapter *adapter)
 
 	IOCTL_DEBUGOUT("ixgbe_set_multi: begin");
 
+	mta = adapter->mta;
+	bzero(mta, sizeof(u8) * IXGBE_ETH_LENGTH_OF_ADDRESS *
+	    MAX_NUM_MULTICAST_ADDRESSES);
+
 	fctrl = IXGBE_READ_REG(&adapter->hw, IXGBE_FCTRL);
 	fctrl |= (IXGBE_FCTRL_UPE | IXGBE_FCTRL_MPE);
 	if (ifp->if_flags & IFF_PROMISC)
diff --git a/sys/dev/ixgbe/ixgbe.h b/sys/dev/ixgbe/ixgbe.h
index 6aa32e4..abfdfa1 100644
--- a/sys/dev/ixgbe/ixgbe.h
+++ b/sys/dev/ixgbe/ixgbe.h
@@ -421,6 +421,8 @@ struct adapter {
 	u64			que_mask;
 	u32			rx_process_limit;
 
+	/* Multicast array memory */
+	u8			*mta;
 	/* Misc stats maintained by the driver */
 	unsigned long   	dropped_pkts;
 	unsigned long   	mbuf_defrag_failed;