gma500: Fix mmap frambuffer
It cannot map correctly if page fault begins from a intermediate address.
[The driver prefaults the mapping, so we need to work from the correct
base address not the faulting address otherwise the map appears offset by
the fault offset]
Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/gma500/framebuffer.c b/drivers/gpu/drm/gma500/framebuffer.c
index 153f9cf..8ea202f 100644
--- a/drivers/gpu/drm/gma500/framebuffer.c
+++ b/drivers/gpu/drm/gma500/framebuffer.c
@@ -125,7 +125,7 @@
unsigned long phys_addr = (unsigned long)dev_priv->stolen_base;
page_num = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
- address = (unsigned long)vmf->virtual_address;
+ address = (unsigned long)vmf->virtual_address - (vmf->pgoff << PAGE_SHIFT);
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);