drm/tegra: fb: Implement ->fb_mmap() callback

This fixes hangs with legacy applications that use the mmap() syscall on
the fbdev device to map framebuffer memory. The fbdev implementation for
mmap() creates a mapping that conflicts with DRM usage and causes a hang
when the memory is accessed through the mapping.

Reported-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tested-by: Stefan Agner <stefan@agner.ch>
Tested-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Reported-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This commit is contained in:
Thierry Reding 2018-02-07 18:45:56 +01:00
parent 04c0746663
commit b8f3f500e0

View file

@ -224,12 +224,28 @@ struct drm_framebuffer *tegra_fb_create(struct drm_device *drm,
}
#ifdef CONFIG_DRM_FBDEV_EMULATION
static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
{
struct drm_fb_helper *helper = info->par;
struct tegra_bo *bo;
int err;
bo = tegra_fb_get_plane(helper->fb, 0);
err = drm_gem_mmap_obj(&bo->gem, bo->gem.size, vma);
if (err < 0)
return err;
return __tegra_gem_mmap(&bo->gem, vma);
}
static struct fb_ops tegra_fb_ops = {
.owner = THIS_MODULE,
DRM_FB_HELPER_DEFAULT_OPS,
.fb_fillrect = drm_fb_helper_sys_fillrect,
.fb_copyarea = drm_fb_helper_sys_copyarea,
.fb_imageblit = drm_fb_helper_sys_imageblit,
.fb_mmap = tegra_fb_mmap,
};
static int tegra_fbdev_probe(struct drm_fb_helper *helper,