1 files changed, 24 insertions, 9 deletions

diff --git a/drivers/misc/sgi-gru/grukservices.c b/drivers/misc/sgi-gru/grukservices.c
index 50b4dd8b0c9f..a0f981022a6c 100644
--- a/drivers/misc/sgi-gru/grukservices.c
+++ b/drivers/misc/sgi-gru/grukservices.c
@@ -503,6 +503,29 @@ static void send_message_queue_interrupt(struct gru_message_queue_desc *mqd)
                                 mqd->interrupt_vector);
 }
 
+/*
+ * Handle a PUT failure. Note: if message was a 2-line message, one of the
+ * lines might have successfully have been written. Before sending the
+ * message, "present" must be cleared in BOTH lines to prevent the receiver
+ * from prematurely seeing the full message.
+ */
+static int send_message_put_nacked(void *cb, struct gru_message_queue_desc *mqd,
+                        void *mesg, int lines)
+{
+        unsigned long m;
+
+        m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
+        if (lines == 2) {
+                gru_vset(cb, m, 0, XTYPE_CL, lines, 1, IMA);
+                if (gru_wait(cb) != CBS_IDLE)
+                        return MQE_UNEXPECTED_CB_ERR;
+        }
+        gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA);
+        if (gru_wait(cb) != CBS_IDLE)
+                return MQE_UNEXPECTED_CB_ERR;
+        send_message_queue_interrupt(mqd);
+        return MQE_OK;
+}
 
 /*
  * Handle a gru_mesq failure. Some of these failures are software recoverable
@@ -512,7 +535,6 @@ static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd,
                                 void *mesg, int lines)
 {
         int substatus, ret = 0;
-        unsigned long m;
 
         substatus = gru_get_cb_message_queue_substatus(cb);
         switch (substatus) {
@@ -534,14 +556,7 @@ static int send_message_failure(void *cb, struct gru_message_queue_desc *mqd,
                 break;
         case CBSS_PUT_NACKED:
                 STAT(mesq_send_put_nacked);
-                m = mqd->mq_gpa + (gru_get_amo_value_head(cb) << 6);
-                gru_vstore(cb, m, gru_get_tri(mesg), XTYPE_CL, lines, 1, IMA);
-                if (gru_wait(cb) == CBS_IDLE) {
-                        ret = MQE_OK;
-                        send_message_queue_interrupt(mqd);
-                } else {
-                        ret = MQE_UNEXPECTED_CB_ERR;
-                }
+                ret = send_message_put_nacked(cb, mqd, mesg, lines);
                 break;
         default:
                 BUG();