misc: mic: Suppress memory space sparse warnings

MIC card and host drivers are able to use virtio over the PCIe bus by
treating ioremap return values for the prefetchable BARs as pointers,
effectively treating I/O memory the same as system memory. However this
results in sparse warnings. Knowing that these warnings do not point to
a functional issue, this patch suppresses these warnings.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Sudeep Dutt <sudeep.dutt@intel.com>
Signed-off-by: Nikhil Rao <nikhil.rao@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mic/card/mic_virtio.c

@@ -256,8 +256,9 @@ static struct virtqueue *mic_find_vq(struct virtio_device *vdev,
 	mvdev->vr[index] = va;
 	memset_io(va, 0x0, _vr_size);
 	vq = vring_new_virtqueue(index, le16_to_cpu(config.num),
-				 MIC_VIRTIO_RING_ALIGN, vdev, false, va,
-				 mic_notify, callback, name);
+				 MIC_VIRTIO_RING_ALIGN, vdev, false,
+				 (void __force *)va, mic_notify, callback,
+				 name);
 	if (!vq) {
 		err = -ENOMEM;
 		goto unmap;
@@ -540,7 +541,8 @@ static void mic_scan_devices(struct mic_driver *mdrv, bool remove)
 			continue;
 
 		/* device already exists */
-		dev = device_find_child(mdrv->dev, d, mic_match_desc);
+		dev = device_find_child(mdrv->dev, (void __force *)d,
+					mic_match_desc);
 		if (dev) {
 			if (remove)
 				iowrite8(MIC_VIRTIO_PARAM_DEV_REMOVE,

drivers/misc/mic/host/mic_virtio.c

@@ -41,7 +41,7 @@ static int mic_virtio_copy_to_user(struct mic_vdev *mvdev,
 	 * We are copying from IO below an should ideally use something
 	 * like copy_to_user_fromio(..) if it existed.
 	 */
-	if (copy_to_user(ubuf, dbuf, len)) {
+	if (copy_to_user(ubuf, (void __force *)dbuf, len)) {
 		err = -EFAULT;
 		dev_err(mic_dev(mvdev), "%s %d err %d\n",
 			__func__, __LINE__, err);
@@ -66,7 +66,7 @@ static int mic_virtio_copy_from_user(struct mic_vdev *mvdev,
 	 * We are copying to IO below and should ideally use something
 	 * like copy_from_user_toio(..) if it existed.
 	 */
-	if (copy_from_user(dbuf, ubuf, len)) {
+	if (copy_from_user((void __force *)dbuf, ubuf, len)) {
 		err = -EFAULT;
 		dev_err(mic_dev(mvdev), "%s %d err %d\n",
 			__func__, __LINE__, err);
@@ -293,8 +293,8 @@ static void mic_virtio_init_post(struct mic_vdev *mvdev)
 			continue;
 		}
 		mvdev->mvr[i].vrh.vring.used =
-			mvdev->mdev->aper.va
-			+ le64_to_cpu(vqconfig[i].used_address);
+			(void __force *)mvdev->mdev->aper.va +
+			le64_to_cpu(vqconfig[i].used_address);
 	}
 
 	mvdev->dc->used_address_updated = 0;