[PATCH V3 4/4] misc: vop: mapping kernel memory to user space as noncached

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


Mapping kernel space memory to user space as noncached, since user space
need check the updates of avail_idx and device page flags timely.

Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx>
---
drivers/misc/mic/vop/vop_vringh.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index b5612183dcb8..b75c2b713a3b 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -1058,7 +1058,7 @@ static int vop_mmap(struct file *f, struct vm_area_struct *vma)
}
err = remap_pfn_range(vma, vma->vm_start + offset,
pa >> PAGE_SHIFT, size,
- vma->vm_page_prot);
+ pgprot_noncached(vma->vm_page_prot));
if (err)
goto ret;
size_rem -= size;
--
2.17.1