Mapping kernel space memory to user space as noncached for noncoherent platform, since user space need check avail_idx and device page flags timely.
Signed-off-by: Joakim Zhang <qiangqing.zh...@nxp.com> Signed-off-by: Sherry Sun <sherry....@nxp.com> --- drivers/misc/mic/vop/vop_vringh.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c index aa2dd240c11e..9850515e8d21 100644 --- a/drivers/misc/mic/vop/vop_vringh.c +++ b/drivers/misc/mic/vop/vop_vringh.c @@ -1139,7 +1139,9 @@ 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); + dev_is_dma_coherent(vop_dev(vdev)) ? vma->vm_page_prot : + pgprot_noncached(vma->vm_page_prot)); + if (err) goto ret; size_rem -= size; -- 2.17.1