Drivers: hv: vmbus: Cleanup vmbus_post_msg()

Posting messages to the host can fail because of transient resource
related failures. Correctly deal with these failures and increase the
number of attempts to post the message before giving up.

In this version of the patch, I have normalized the error code to
Linux error code.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index ae22e3c1fc4c189f675b1ccd2c18cf90d5d4d8fc..e206619b946e577ff79b65a7273cfe5784964649 100644 (file)
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -427,10 +427,21 @@ int vmbus_post_msg(void *buffer, size_t buflen)
         * insufficient resources. Retry the operation a couple of
         * times before giving up.
         */
-       while (retries < 3) {
-               ret =  hv_post_message(conn_id, 1, buffer, buflen);
-               if (ret != HV_STATUS_INSUFFICIENT_BUFFERS)
+       while (retries < 10) {
+               ret = hv_post_message(conn_id, 1, buffer, buflen);
+
+               switch (ret) {
+               case HV_STATUS_INSUFFICIENT_BUFFERS:
+                       ret = -ENOMEM;
+               case -ENOMEM:
+                       break;
+               case HV_STATUS_SUCCESS:
                        return ret;
+               default:
+                       pr_err("hv_post_msg() failed; error code:%d\n", ret);
+                       return -EINVAL;
+               }
+
                retries++;
                msleep(100);
        }