Added Little Endian support to vtpm module

commit eb71f8a5 upstream.

The tpm_ibmvtpm module is affected by an unaligned access problem.
ibmvtpm_crq_get_version failed with rc=-4 during boot when vTPM is
enabled in Power partition, which supports both little endian and
big endian modes.

We added little endian support to fix this problem:
1) added cpu_to_be64 calls to ensure BE data is sent from an LE OS.
2) added be16_to_cpu and be32_to_cpu calls to make sure data received
   is in LE format on a LE OS.
Signed-off-by: Hon Ching(Vicky) Lo <honclo@linux.vnet.ibm.com>
Signed-off-by: Joy Latten <jmlatten@linux.vnet.ibm.com>
[phuewe: manually applied the patch :( ]
Reviewed-by: Ashley Lai <ashley@ahsleylai.com>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

drivers/char/tpm/tpm_ibmvtpm.c

@@ -148,7 +148,8 @@ static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
 	crq.len = (u16)count;
 	crq.data = ibmvtpm->rtce_dma_handle;
 
-	rc = ibmvtpm_send_crq(ibmvtpm->vdev, word[0], word[1]);
+	rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(word[0]),
+			      cpu_to_be64(word[1]));
 	if (rc != H_SUCCESS) {
 		dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
 		rc = 0;
@@ -186,7 +187,8 @@ static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
 	crq.valid = (u8)IBMVTPM_VALID_CMD;
 	crq.msg = (u8)VTPM_GET_RTCE_BUFFER_SIZE;
 
-	rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
+	rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]),
+			      cpu_to_be64(buf[1]));
 	if (rc != H_SUCCESS)
 		dev_err(ibmvtpm->dev,
 			"ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
@@ -212,7 +214,8 @@ static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
 	crq.valid = (u8)IBMVTPM_VALID_CMD;
 	crq.msg = (u8)VTPM_GET_VERSION;
 
-	rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
+	rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]),
+			      cpu_to_be64(buf[1]));
 	if (rc != H_SUCCESS)
 		dev_err(ibmvtpm->dev,
 			"ibmvtpm_crq_get_version failed rc=%d\n", rc);
@@ -335,7 +338,8 @@ static int tpm_ibmvtpm_suspend(struct device *dev)
 	crq.valid = (u8)IBMVTPM_VALID_CMD;
 	crq.msg = (u8)VTPM_PREPARE_TO_SUSPEND;
 
-	rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
+	rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]),
+			      cpu_to_be64(buf[1]));
 	if (rc != H_SUCCESS)
 		dev_err(ibmvtpm->dev,
 			"tpm_ibmvtpm_suspend failed rc=%d\n", rc);
@@ -519,11 +523,11 @@ static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
 	case IBMVTPM_VALID_CMD:
 		switch (crq->msg) {
 		case VTPM_GET_RTCE_BUFFER_SIZE_RES:
-			if (crq->len <= 0) {
+			if (be16_to_cpu(crq->len) <= 0) {
 				dev_err(ibmvtpm->dev, "Invalid rtce size\n");
 				return;
 			}
-			ibmvtpm->rtce_size = crq->len;
+			ibmvtpm->rtce_size = be16_to_cpu(crq->len);
 			ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
 						    GFP_KERNEL);
 			if (!ibmvtpm->rtce_buf) {
@@ -544,11 +548,11 @@ static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
 
 			return;
 		case VTPM_GET_VERSION_RES:
-			ibmvtpm->vtpm_version = crq->data;
+			ibmvtpm->vtpm_version = be32_to_cpu(crq->data);
 			return;
 		case VTPM_TPM_COMMAND_RES:
 			/* len of the data in rtce buffer */
-			ibmvtpm->res_len = crq->len;
+			ibmvtpm->res_len = be16_to_cpu(crq->len);
 			wake_up_interruptible(&ibmvtpm->wq);
 			return;
 		default: