s390/zcrypt: use explicit return code for flushed requests

If a AP device is removed while messages are still pending, the requests
are cancelled by calling the message receive function with an error pointer
for the reply. The message type receive handler recognize this and create
a fake hardware error TYPE82_RSP_CODE / REP82_ERROR_MACHINE_FAILURE.
The message with the hardware error then causes a printk and a return
code of -EAGAIN.

Replace the intricate scheme with an explicit return code for this sitation
and avoid the error message.

Reviewd-by: Ingo Tuchscherer <ingo.tuchscherer@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

6 files changed, 88 insertions, 66 deletions

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index ba1f806..7224bf7 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1027,12 +1027,14 @@ static void __ap_flush_queue(struct ap_device *ap_dev)
 	list_for_each_entry_safe(ap_msg, next, &ap_dev->pendingq, list) {
 		list_del_init(&ap_msg->list);
 		ap_dev->pendingq_count--;
-		ap_msg->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
+		ap_msg->rc = -EAGAIN;
+		ap_msg->receive(ap_dev, ap_msg, NULL);
 	}
 	list_for_each_entry_safe(ap_msg, next, &ap_dev->requestq, list) {
 		list_del_init(&ap_msg->list);
 		ap_dev->requestq_count--;
-		ap_msg->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
+		ap_msg->rc = -EAGAIN;
+		ap_msg->receive(ap_dev, ap_msg, NULL);
 	}
 }
 
@@ -1690,10 +1692,12 @@ static int __ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_ms
 			return -EBUSY;
 		case AP_RESPONSE_REQ_FAC_NOT_INST:
 		case AP_RESPONSE_MESSAGE_TOO_BIG:
-			ap_msg->receive(ap_dev, ap_msg, ERR_PTR(-EINVAL));
+			ap_msg->rc = -EINVAL;
+			ap_msg->receive(ap_dev, ap_msg, NULL);
 			return -EINVAL;
 		default:	/* Device is gone. */
-			ap_msg->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
+			ap_msg->rc = -ENODEV;
+			ap_msg->receive(ap_dev, ap_msg, NULL);
 			return -ENODEV;
 		}
 	} else {
@@ -1726,7 +1730,8 @@ void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg)
 		if (rc == -ENODEV)
 			ap_dev->unregistered = 1;
 	} else {
-		ap_msg->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV));
+		ap_msg->rc = -ENODEV;
+		ap_msg->receive(ap_dev, ap_msg, NULL);
 		rc = -ENODEV;
 	}
 	spin_unlock_bh(&ap_dev->lock);
diff --git a/drivers/s390/crypto/ap_bus.h b/drivers/s390/crypto/ap_bus.h
index 83cc9e4..af9b705 100644
--- a/drivers/s390/crypto/ap_bus.h
+++ b/drivers/s390/crypto/ap_bus.h
@@ -187,6 +187,7 @@ struct ap_message {
 	unsigned long long psmid;	/* Message id. */
 	void *message;			/* Pointer to message buffer. */
 	size_t length;			/* Message length. */
+	int rc;				/* Return code for this message */
 
 	void *private;			/* ap driver private pointer. */
 	unsigned int special:1;		/* Used for special commands. */
@@ -219,6 +220,7 @@ static inline void ap_init_message(struct ap_message *ap_msg)
 {
 	ap_msg->psmid = 0;
 	ap_msg->length = 0;
+	ap_msg->rc = 0;
 	ap_msg->special = 0;
 	ap_msg->receive = NULL;
 }
diff --git a/drivers/s390/crypto/zcrypt_msgtype50.c b/drivers/s390/crypto/zcrypt_msgtype50.c
index 6c9af13..71ceee9 100644
--- a/drivers/s390/crypto/zcrypt_msgtype50.c
+++ b/drivers/s390/crypto/zcrypt_msgtype50.c
@@ -395,10 +395,8 @@ static void zcrypt_cex2a_receive(struct ap_device *ap_dev,
 	int length;
 
 	/* Copy the reply message to the request message buffer. */
-	if (IS_ERR(reply)) {
-		memcpy(msg->message, &error_reply, sizeof(error_reply));
-		goto out;
-	}
+	if (!reply)
+		goto out;	/* ap_msg->rc indicates the error */
 	t80h = reply->message;
 	if (t80h->type == TYPE80_RSP_CODE) {
 		if (ap_dev->device_type == AP_DEVICE_TYPE_CEX2A)
@@ -449,10 +447,12 @@ static long zcrypt_cex2a_modexpo(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, mex->outputdata,
-				      mex->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, mex->outputdata,
+					      mex->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -493,10 +493,12 @@ static long zcrypt_cex2a_modexpo_crt(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, crt->outputdata,
-				      crt->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, crt->outputdata,
+					      crt->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
diff --git a/drivers/s390/crypto/zcrypt_msgtype6.c b/drivers/s390/crypto/zcrypt_msgtype6.c
index 46b324c..7476221 100644
--- a/drivers/s390/crypto/zcrypt_msgtype6.c
+++ b/drivers/s390/crypto/zcrypt_msgtype6.c
@@ -829,10 +829,8 @@ static void zcrypt_msgtype6_receive(struct ap_device *ap_dev,
 	int length;
 
 	/* Copy the reply message to the request message buffer. */
-	if (IS_ERR(reply)) {
-		memcpy(msg->message, &error_reply, sizeof(error_reply));
-		goto out;
-	}
+	if (!reply)
+		goto out;	/* ap_msg->rc indicates the error */
 	t86r = reply->message;
 	if (t86r->hdr.type == TYPE86_RSP_CODE &&
 		 t86r->cprbx.cprb_ver_id == 0x02) {
@@ -880,10 +878,8 @@ static void zcrypt_msgtype6_receive_ep11(struct ap_device *ap_dev,
 	int length;
 
 	/* Copy the reply message to the request message buffer. */
-	if (IS_ERR(reply)) {
-		memcpy(msg->message, &error_reply, sizeof(error_reply));
-		goto out;
-	}
+	if (!reply)
+		goto out;	/* ap_msg->rc indicates the error */
 	t86r = reply->message;
 	if (t86r->hdr.type == TYPE86_RSP_CODE &&
 	    t86r->cprbx.cprb_ver_id == 0x04) {
@@ -935,10 +931,13 @@ static long zcrypt_msgtype6_modexpo(struct zcrypt_device *zdev,
 	init_completion(&resp_type.work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&resp_type.work);
-	if (rc == 0)
-		rc = convert_response_ica(zdev, &ap_msg, mex->outputdata,
-					  mex->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response_ica(zdev, &ap_msg,
+						  mex->outputdata,
+						  mex->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -976,10 +975,13 @@ static long zcrypt_msgtype6_modexpo_crt(struct zcrypt_device *zdev,
 	init_completion(&resp_type.work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&resp_type.work);
-	if (rc == 0)
-		rc = convert_response_ica(zdev, &ap_msg, crt->outputdata,
-					  crt->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response_ica(zdev, &ap_msg,
+						  crt->outputdata,
+						  crt->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -1017,9 +1019,11 @@ static long zcrypt_msgtype6_send_cprb(struct zcrypt_device *zdev,
 	init_completion(&resp_type.work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&resp_type.work);
-	if (rc == 0)
-		rc = convert_response_xcrb(zdev, &ap_msg, xcRB);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response_xcrb(zdev, &ap_msg, xcRB);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -1057,9 +1061,12 @@ static long zcrypt_msgtype6_send_ep11_cprb(struct zcrypt_device *zdev,
 	init_completion(&resp_type.work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&resp_type.work);
-	if (rc == 0)
-		rc = convert_response_ep11_xcrb(zdev, &ap_msg, xcrb);
-	else /* Signal pending. */
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response_ep11_xcrb(zdev, &ap_msg, xcrb);
+	} else
+		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 
 out_free:
@@ -1096,9 +1103,11 @@ static long zcrypt_msgtype6_rng(struct zcrypt_device *zdev,
 	init_completion(&resp_type.work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&resp_type.work);
-	if (rc == 0)
-		rc = convert_response_rng(zdev, &ap_msg, buffer);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response_rng(zdev, &ap_msg, buffer);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 	kfree(ap_msg.message);
diff --git a/drivers/s390/crypto/zcrypt_pcica.c b/drivers/s390/crypto/zcrypt_pcica.c
index 2f22020..6af9c9f 100644
--- a/drivers/s390/crypto/zcrypt_pcica.c
+++ b/drivers/s390/crypto/zcrypt_pcica.c
@@ -258,10 +258,8 @@ static void zcrypt_pcica_receive(struct ap_device *ap_dev,
 	int length;
 
 	/* Copy the reply message to the request message buffer. */
-	if (IS_ERR(reply)) {
-		memcpy(msg->message, &error_reply, sizeof(error_reply));
-		goto out;
-	}
+	if (!reply)
+		goto out;	/* ap_msg->rc indicates the error */
 	t84h = reply->message;
 	if (t84h->code == TYPE84_RSP_CODE) {
 		length = min(PCICA_MAX_RESPONSE_SIZE, (int) t84h->len);
@@ -302,10 +300,12 @@ static long zcrypt_pcica_modexpo(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, mex->outputdata,
-				      mex->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, mex->outputdata,
+					      mex->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -341,10 +341,12 @@ static long zcrypt_pcica_modexpo_crt(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, crt->outputdata,
-				      crt->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, crt->outputdata,
+					      crt->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
diff --git a/drivers/s390/crypto/zcrypt_pcicc.c b/drivers/s390/crypto/zcrypt_pcicc.c
index 9f18876..4cf2115 100644
--- a/drivers/s390/crypto/zcrypt_pcicc.c
+++ b/drivers/s390/crypto/zcrypt_pcicc.c
@@ -461,10 +461,8 @@ static void zcrypt_pcicc_receive(struct ap_device *ap_dev,
 	int length;
 
 	/* Copy the reply message to the request message buffer. */
-	if (IS_ERR(reply)) {
-		memcpy(msg->message, &error_reply, sizeof(error_reply));
-		goto out;
-	}
+	if (!reply)
+		goto out;	/* ap_msg->rc indicates the error */
 	t86r = reply->message;
 	if (t86r->hdr.type == TYPE86_RSP_CODE &&
 		 t86r->cprb.cprb_ver_id == 0x01) {
@@ -508,10 +506,12 @@ static long zcrypt_pcicc_modexpo(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, mex->outputdata,
-				      mex->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, mex->outputdata,
+					      mex->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free:
@@ -548,10 +548,12 @@ static long zcrypt_pcicc_modexpo_crt(struct zcrypt_device *zdev,
 	init_completion(&work);
 	ap_queue_message(zdev->ap_dev, &ap_msg);
 	rc = wait_for_completion_interruptible(&work);
-	if (rc == 0)
-		rc = convert_response(zdev, &ap_msg, crt->outputdata,
-				      crt->outputdatalength);
-	else
+	if (rc == 0) {
+		rc = ap_msg.rc;
+		if (rc == 0)
+			rc = convert_response(zdev, &ap_msg, crt->outputdata,
+					      crt->outputdatalength);
+	} else
 		/* Signal pending. */
 		ap_cancel_message(zdev->ap_dev, &ap_msg);
 out_free: