[PATCH 104/115] ion: use vm_insert_pfn for faulted pages

John Stultz
2013-12-14T03:27:50Z

From: Colin Cross <ccross@android.com>

Most ion userspace mappings are created with remap_pfn_range. Use
vm_insert_pfn instead of vm_insert_page to make faulted cached
mappings look more like uncached mappings.

Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
drivers/staging/android/ion/ion.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
index fc77aa6..45127f5 100644
--- a/drivers/staging/android/ion/ion.c
+++ b/drivers/staging/android/ion/ion.c
@@ -890,14 +890,15 @@ static void ion_buffer_sync_for_device(struct ion_buffer *buffer,
int ion_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct ion_buffer *buffer = vma->vm_private_data;
+ unsigned long pfn;
int ret;

mutex_lock(&buffer->lock);
ion_buffer_page_dirty(buffer->pages + vmf->pgoff);
-
BUG_ON(!buffer->pages || !buffer->pages[vmf->pgoff]);
- ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address,
- ion_buffer_page(buffer->pages[vmf->pgoff]));
+
+ pfn = page_to_pfn(ion_buffer_page(buffer->pages[vmf->pgoff]));
+ ret = vm_insert_pfn(vma, (unsigned long)vmf->virtual_address, pfn);
mutex_unlock(&buffer->lock);
if (ret)
return VM_FAULT_ERROR;
@@ -956,6 +957,8 @@ static int ion_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma)
}

if (ion_buffer_fault_user_mappings(buffer)) {
+ vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND |
+ VM_DONTDUMP;
vma->vm_private_data = buffer;
vma->vm_ops = &ion_vma_ops;
ion_vm_open(vma);
--
1.8.3.2