staging: unisys: visornic - check visorchannel_signalinsert/remove failures

Logic to check for failures of visorchannel_signalinsert() and
visorchannel_signalremove() were added, and a new sent_post_failed counter
tracks the number of times we failed to post a rcv buffer to the IO
partition.
Signed-off-by: Tim Sell <Timothy.Sell@unisys.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/visornic/visornic_main.c

@@ -102,6 +102,7 @@ struct chanstat {
 	unsigned long sent_enbdis;
 	unsigned long sent_promisc;
 	unsigned long sent_post;
+	unsigned long sent_post_failed;
 	unsigned long sent_xmit;
 	unsigned long reject_count;
 	unsigned long extra_rcvbufs_sent;
@@ -479,11 +480,14 @@ post_skb(struct uiscmdrsp *cmdrsp,
 	if ((cmdrsp->net.rcvpost.frag.pi_off + skb->len) <= PI_PAGE_SIZE) {
 		cmdrsp->net.type = NET_RCV_POST;
 		cmdrsp->cmdtype = CMD_NET_TYPE;
-		visorchannel_signalinsert(devdata->dev->visorchannel,
+		if (visorchannel_signalinsert(devdata->dev->visorchannel,
 					  IOCHAN_TO_IOPART,
-					  cmdrsp);
+					  cmdrsp)) {
 			atomic_inc(&devdata->num_rcvbuf_in_iovm);
 			devdata->chstat.sent_post++;
+		} else {
+			devdata->chstat.sent_post_failed++;
+		}
 	}
 }
 
@@ -505,9 +509,9 @@ send_enbdis(struct net_device *netdev, int state,
 	devdata->cmdrsp_rcv->net.enbdis.context = netdev;
 	devdata->cmdrsp_rcv->net.type = NET_RCV_ENBDIS;
 	devdata->cmdrsp_rcv->cmdtype = CMD_NET_TYPE;
-	visorchannel_signalinsert(devdata->dev->visorchannel,
+	if (visorchannel_signalinsert(devdata->dev->visorchannel,
 				  IOCHAN_TO_IOPART,
-				  devdata->cmdrsp_rcv);
+				  devdata->cmdrsp_rcv))
 		devdata->chstat.sent_enbdis++;
 }
 
@@ -1501,6 +1505,9 @@ static ssize_t info_debugfs_read(struct file *file, char __user *buf,
 		str_pos += scnprintf(vbuf + str_pos, len - str_pos,
 				     " chstat.sent_post = %lu\n",
 				     devdata->chstat.sent_post);
+		str_pos += scnprintf(vbuf + str_pos, len - str_pos,
+				     " chstat.sent_post_failed = %lu\n",
+				     devdata->chstat.sent_post_failed);
 		str_pos += scnprintf(vbuf + str_pos, len - str_pos,
 				     " chstat.sent_xmit = %lu\n",
 				     devdata->chstat.sent_xmit);