1 files changed, 35 insertions, 6 deletions

diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
index a75ca63deea6..bfaf59b02bda 100644
--- a/drivers/gpu/drm/drm_drv.c
+++ b/drivers/gpu/drm/drm_drv.c
@@ -145,6 +145,7 @@ static struct drm_ioctl_desc drm_ioctls[] = {
         DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_MASTER|DRM_CONTROL_ALLOW),
         DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_MASTER|DRM_CONTROL_ALLOW),
         DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb, DRM_MASTER|DRM_CONTROL_ALLOW),
+        DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW),
 };
 
 #define DRM_CORE_IOCTL_COUNT    ARRAY_SIZE( drm_ioctls )
@@ -366,6 +367,29 @@ module_init(drm_core_init);
 module_exit(drm_core_exit);
 
 /**
+ * Copy and IOCTL return string to user space
+ */
+static int drm_copy_field(char *buf, size_t *buf_len, const char *value)
+{
+        int len;
+
+        /* don't overflow userbuf */
+        len = strlen(value);
+        if (len > *buf_len)
+                len = *buf_len;
+
+        /* let userspace know exact length of driver value (which could be
+         * larger than the userspace-supplied buffer) */
+        *buf_len = strlen(value);
+
+        /* finally, try filling in the userbuf */
+        if (len && buf)
+                if (copy_to_user(buf, value, len))
+                        return -EFAULT;
+        return 0;
+}
+
+/**
  * Get version information
  *
  * \param inode device inode.
@@ -380,16 +404,21 @@ static int drm_version(struct drm_device *dev, void *data,
                        struct drm_file *file_priv)
 {
         struct drm_version *version = data;
-        int len;
+        int err;
 
         version->version_major = dev->driver->major;
         version->version_minor = dev->driver->minor;
         version->version_patchlevel = dev->driver->patchlevel;
-        DRM_COPY(version->name, dev->driver->name);
-        DRM_COPY(version->date, dev->driver->date);
-        DRM_COPY(version->desc, dev->driver->desc);
-
-        return 0;
+        err = drm_copy_field(version->name, &version->name_len,
+                        dev->driver->name);
+        if (!err)
+                err = drm_copy_field(version->date, &version->date_len,
+                                dev->driver->date);
+        if (!err)
+                err = drm_copy_field(version->desc, &version->desc_len,
+                                dev->driver->desc);
+
+        return err;
 }
 
 /**