[S390] zcrypt: fix request timeout handling

Under very high load zcrypt requests may timeout while waiting on the
request queue. Modify zcrypt that timeouts are based on crypto adapter
responses. A timeout occurs only if a crypto adapter does not respond
within a given time frame to sumitted requests.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 9 insertions, 18 deletions

diff --git a/drivers/s390/crypto/zcrypt_cex2a.c b/drivers/s390/crypto/zcrypt_cex2a.c
index 5bb13a9d0898..08657f604b8c 100644
--- a/drivers/s390/crypto/zcrypt_cex2a.c
+++ b/drivers/s390/crypto/zcrypt_cex2a.c
@@ -70,6 +70,7 @@ static struct ap_driver zcrypt_cex2a_driver = {
         .remove = zcrypt_cex2a_remove,
         .receive = zcrypt_cex2a_receive,
         .ids = zcrypt_cex2a_ids,
+        .request_timeout = CEX2A_CLEANUP_TIME,
 };
 
 /**
@@ -306,18 +307,13 @@ static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev,
                 goto out_free;
         init_completion(&work);
         ap_queue_message(zdev->ap_dev, &ap_msg);
-        rc = wait_for_completion_interruptible_timeout(
-                                &work, CEX2A_CLEANUP_TIME);
-        if (rc > 0)
+        rc = wait_for_completion_interruptible(&work);
+        if (rc == 0)
                 rc = convert_response(zdev, &ap_msg, mex->outputdata,
                                       mex->outputdatalength);
-        else {
-                /* Signal pending or message timed out. */
+        else
+                /* Signal pending. */
                 ap_cancel_message(zdev->ap_dev, &ap_msg);
-                if (rc == 0)
-                        /* Message timed out. */
-                        rc = -ETIME;
-        }
 out_free:
         kfree(ap_msg.message);
         return rc;
@@ -348,18 +344,13 @@ static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev,
                 goto out_free;
         init_completion(&work);
         ap_queue_message(zdev->ap_dev, &ap_msg);
-        rc = wait_for_completion_interruptible_timeout(
-                                &work, CEX2A_CLEANUP_TIME);
-        if (rc > 0)
+        rc = wait_for_completion_interruptible(&work);
+        if (rc == 0)
                 rc = convert_response(zdev, &ap_msg, crt->outputdata,
                                       crt->outputdatalength);
-        else {
-                /* Signal pending or message timed out. */
+        else
+                /* Signal pending. */
                 ap_cancel_message(zdev->ap_dev, &ap_msg);
-                if (rc == 0)
-                        /* Message timed out. */
-                        rc = -ETIME;
-        }
 out_free:
         kfree(ap_msg.message);
         return rc;