[PATCH V2 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys

[Sherry Sun <sherry.sun@xxxxxxx>]

The device page and vring should use consistent memory which are
allocated by dma_alloc_coherent api, when user space wants to get its
physical address, virt_to_phys cannot be used, should simply return the
saved device page dma address by get_dp_dma callback and the vring dma
address saved in mic_vqconfig.

Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
---
 drivers/misc/mic/bus/vop_bus.h    |  2 ++
 drivers/misc/mic/host/mic_boot.c  |  8 ++++++++
 drivers/misc/mic/vop/vop_vringh.c | 11 +++++++++--
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/misc/mic/bus/vop_bus.h b/drivers/misc/mic/bus/vop_bus.h
index 4fa02808c1e2..d891eacae358 100644
--- a/drivers/misc/mic/bus/vop_bus.h
+++ b/drivers/misc/mic/bus/vop_bus.h
@@ -75,6 +75,7 @@ struct vop_driver {
  *                 node to add/remove/configure virtio devices.
  * @get_dp: Get access to the virtio device page used by the self
  *          node to add/remove/configure virtio devices.
+ * @get_dp_dma: Get dma address of the virtio device page.
  * @send_intr: Send an interrupt to the peer node on a specified doorbell.
  * @remap: Map a buffer with the specified DMA address and length.
  * @unmap: Unmap a buffer previously mapped.
@@ -92,6 +93,7 @@ struct vop_hw_ops {
 	void (*ack_interrupt)(struct vop_device *vpdev, int num);
 	void __iomem * (*get_remote_dp)(struct vop_device *vpdev);
 	void * (*get_dp)(struct vop_device *vpdev);
+	dma_addr_t (*get_dp_dma)(struct vop_device *vpdev);
 	void (*send_intr)(struct vop_device *vpdev, int db);
 	void __iomem * (*remap)(struct vop_device *vpdev,
 				  dma_addr_t pa, size_t len);
diff --git a/drivers/misc/mic/host/mic_boot.c b/drivers/misc/mic/host/mic_boot.c
index fb5b3989753d..ced03662cd8f 100644
--- a/drivers/misc/mic/host/mic_boot.c
+++ b/drivers/misc/mic/host/mic_boot.c
@@ -88,6 +88,13 @@ static void *__mic_get_dp(struct vop_device *vpdev)
 	return mdev->dp;
 }
 
+static dma_addr_t __mic_get_dp_dma(struct vop_device *vpdev)
+{
+	struct mic_device *mdev = vpdev_to_mdev(&vpdev->dev);
+
+	return mdev->dp_dma_addr;
+}
+
 static void __iomem *__mic_get_remote_dp(struct vop_device *vpdev)
 {
 	return NULL;
@@ -119,6 +126,7 @@ static struct vop_hw_ops vop_hw_ops = {
 	.ack_interrupt = __mic_ack_interrupt,
 	.next_db = __mic_next_db,
 	.get_dp = __mic_get_dp,
+	.get_dp_dma = __mic_get_dp_dma,
 	.get_remote_dp = __mic_get_remote_dp,
 	.send_intr = __mic_send_intr,
 	.remap = __mic_ioremap,
diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index 422a28c1bb7a..4d5feb39aeb7 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -995,6 +995,7 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
 		 unsigned long *size, unsigned long *pa)
 {
 	struct vop_device *vpdev = vdev->vpdev;
+	struct mic_vqconfig *vqconfig = mic_vq_config(vdev->dd);
 	unsigned long start = MIC_DP_SIZE;
 	int i;
 
@@ -1007,7 +1008,13 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
 	 * ....
 	 */
 	if (!offset) {
-		*pa = virt_to_phys(vpdev->hw_ops->get_dp(vpdev));
+		if (vpdev->hw_ops->get_dp_dma)
+			*pa = vpdev->hw_ops->get_dp_dma(vpdev);
+		else {
+			dev_err(vop_dev(vdev), "can't get device page physical address\n");
+			return -EINVAL;
+		}
+
 		*size = MIC_DP_SIZE;
 		return 0;
 	}
@@ -1016,7 +1023,7 @@ vop_query_offset(struct vop_vdev *vdev, unsigned long offset,
 		struct vop_vringh *vvr = &vdev->vvr[i];
 
 		if (offset == start) {
-			*pa = virt_to_phys(vvr->vring.va);
+			*pa = vqconfig[i].address;
 			*size = vvr->vring.len;
 			return 0;
 		}
-- 
2.17.1