[PATCH V3 3/4] misc: vop: simply return the saved dma address instead of virt_to_phys

From: Sherry Sun
Date: Thu Oct 22 2020 - 01:08:17 EST


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 | 8 +++++++-
3 files changed, 17 insertions(+), 1 deletion(-)

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 8cb85b8b3e19..9591bf609f57 100644
--- a/drivers/misc/mic/host/mic_boot.c
+++ b/drivers/misc/mic/host/mic_boot.c
@@ -89,6 +89,13 @@ 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;
@@ -120,6 +127,7 @@ 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 cc928d45af5a..b5612183dcb8 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -1009,7 +1009,13 @@ 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;
}
--
2.17.1