drm: Make handling of dev_priv->vblank_pipe more robust.
Initialize it to default value if it hasn't been set by the X server yet.
In i915_vblank_pipe_set(), only update dev_priv->vblank_pipe and call
i915_enable_interrupt() if the argument passed from userspace is valid to avoid
corrupting dev_priv->vblank_pipe on invalid arguments.
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/i915_irq.c b/drivers/char/drm/i915_irq.c
index d564556..e9e46c4 100644
--- a/drivers/char/drm/i915_irq.c
+++ b/drivers/char/drm/i915_irq.c
@@ -304,7 +304,7 @@
return i915_wait_irq(dev, irqwait.irq_seq);
}
-static int i915_enable_interrupt (drm_device_t *dev)
+static void i915_enable_interrupt (drm_device_t *dev)
{
drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
u16 flag;
@@ -314,13 +314,8 @@
flag |= VSYNC_PIPEA_FLAG;
if (dev_priv->vblank_pipe & DRM_I915_VBLANK_PIPE_B)
flag |= VSYNC_PIPEB_FLAG;
- if (dev_priv->vblank_pipe & ~(DRM_I915_VBLANK_PIPE_A|DRM_I915_VBLANK_PIPE_B)) {
- DRM_ERROR("%s called with invalid pipe 0x%x\n",
- __FUNCTION__, dev_priv->vblank_pipe);
- return DRM_ERR(EINVAL);
- }
+
I915_WRITE16(I915REG_INT_ENABLE_R, USER_INT_FLAG | flag);
- return 0;
}
/* Set the vblank monitor pipe
@@ -339,8 +334,17 @@
DRM_COPY_FROM_USER_IOCTL(pipe, (drm_i915_vblank_pipe_t __user *) data,
sizeof(pipe));
+ if (pipe.pipe & ~(DRM_I915_VBLANK_PIPE_A|DRM_I915_VBLANK_PIPE_B)) {
+ DRM_ERROR("%s called with invalid pipe 0x%x\n",
+ __FUNCTION__, pipe.pipe);
+ return DRM_ERR(EINVAL);
+ }
+
dev_priv->vblank_pipe = pipe.pipe;
- return i915_enable_interrupt (dev);
+
+ i915_enable_interrupt (dev);
+
+ return 0;
}
int i915_vblank_pipe_get(DRM_IOCTL_ARGS)
@@ -502,6 +506,8 @@
INIT_LIST_HEAD(&dev_priv->vbl_swaps.head);
dev_priv->swaps_pending = 0;
+ if (!dev_priv->vblank_pipe)
+ dev_priv->vblank_pipe = DRM_I915_VBLANK_PIPE_A;
i915_enable_interrupt(dev);
DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
}
