drm: GEM mmap support
Add core support for mapping of GEM objects. Drivers should provide a
vm_operations_struct if they want to support page faulting of objects.
The code for handling GEM object offsets was taken from TTM, which was
written by Thomas Hellström.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_fops.c b/drivers/gpu/drm/drm_fops.c
index f228523..3a6c439 100644
--- a/drivers/gpu/drm/drm_fops.c
+++ b/drivers/gpu/drm/drm_fops.c
@@ -133,11 +133,21 @@
spin_lock(&dev->count_lock);
if (!dev->open_count++) {
spin_unlock(&dev->count_lock);
- return drm_setup(dev);
+ retcode = drm_setup(dev);
+ goto out;
}
spin_unlock(&dev->count_lock);
}
+out:
+ mutex_lock(&dev->struct_mutex);
+ if (dev->dev_mapping == NULL)
+ dev->dev_mapping = inode->i_mapping;
+ else if (dev->dev_mapping != inode->i_mapping)
+ WARN(1, "dev->dev_mapping not inode mapping (%p expected %p)\n",
+ dev->dev_mapping, inode->i_mapping);
+ mutex_unlock(&dev->struct_mutex);
+
return retcode;
}
EXPORT_SYMBOL(drm_open);