Completely re-initialize DMA settings

There were two problems. First, the 'warp' and 'primary' pointers weren't
    cleared, so mga_do_cleanup_dma, which gets called multiple times, would
    try to ioremapfree them multiple times. This resulted in the new error
    messages to syslog. The second problem was the, since the dev_private
    structure isn't reallocated and cleaned out in mga_do_init_dma, when
    the server is reloaded idle-waits would wait for impossible values.
I have given this patch some more riggorous testing. This includes:
- Load module, start server, run GL app, stop server, unload module.
- Load module, start server, run GL app, stop server, unload module, reload
    module, restart server, run GL app.
- Load module, start server, run GL app, stop server, restart server, run
    GL app, stop server, unload module.
In all three cases, everything worked as expected. Please let me know if
    there are any further regressions with this patch.
Xorg bug: 3408 Reported by: Chris Rankin

1 files changed, 33 insertions, 24 deletions

diff --git a/shared-core/mga_dma.c b/shared-core/mga_dma.c
index 367c670e..4c0be4cc 100644
--- a/shared-core/mga_dma.c
+++ b/shared-core/mga_dma.c
@@ -440,38 +440,32 @@ static int mga_do_init_dma(drm_device_t * dev, drm_mga_init_t * init)
 
 	if (!dev_priv->sarea) {
 		DRM_ERROR("failed to find sarea!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 
 	dev_priv->mmio = drm_core_findmap(dev, init->mmio_offset);
 	if (!dev_priv->mmio) {
 		DRM_ERROR("failed to find mmio region!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 	dev_priv->status = drm_core_findmap(dev, init->status_offset);
 	if (!dev_priv->status) {
 		DRM_ERROR("failed to find status page!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 	dev_priv->warp = drm_core_findmap(dev, init->warp_offset);
 	if (!dev_priv->warp) {
 		DRM_ERROR("failed to find warp microcode region!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 	dev_priv->primary = drm_core_findmap(dev, init->primary_offset);
 	if (!dev_priv->primary) {
 		DRM_ERROR("failed to find primary dma region!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 	dev->agp_buffer_map = drm_core_findmap(dev, init->buffers_offset);
 	if (!dev->agp_buffer_map) {
 		DRM_ERROR("failed to find dma buffer region!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(EINVAL);
 	}
 
@@ -486,21 +480,18 @@ static int mga_do_init_dma(drm_device_t * dev, drm_mga_init_t * init)
 	if (!dev_priv->warp->handle ||
 	    !dev_priv->primary->handle || !dev->agp_buffer_map->handle) {
 		DRM_ERROR("failed to ioremap agp regions!\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(ENOMEM);
 	}
 
 	ret = mga_warp_install_microcode(dev_priv);
 	if (ret < 0) {
 		DRM_ERROR("failed to install WARP ucode!\n");
-		mga_do_cleanup_dma(dev);
 		return ret;
 	}
 
 	ret = mga_warp_init(dev_priv);
 	if (ret < 0) {
 		DRM_ERROR("failed to init WARP engine!\n");
-		mga_do_cleanup_dma(dev);
 		return ret;
 	}
 
@@ -539,7 +530,6 @@ static int mga_do_init_dma(drm_device_t * dev, drm_mga_init_t * init)
 
 	if (mga_freelist_init(dev, dev_priv) < 0) {
 		DRM_ERROR("could not initialize freelist\n");
-		mga_do_cleanup_dma(dev);
 		return DRM_ERR(ENOMEM);
 	}
 
@@ -564,10 +554,20 @@ static int mga_do_cleanup_dma(drm_device_t * dev)
 			drm_core_ioremapfree(dev_priv->warp, dev);
 		if (dev_priv->primary != NULL)
 			drm_core_ioremapfree(dev_priv->primary, dev);
-		if (dev->agp_buffer_map != NULL) {
+		if (dev->agp_buffer_map != NULL)
 			drm_core_ioremapfree(dev->agp_buffer_map, dev);
-			dev->agp_buffer_map = NULL;
-		}
+
+		dev_priv->warp = NULL;
+		dev_priv->primary = NULL;
+		dev_priv->mmio = NULL;
+		dev_priv->status = NULL;
+		dev_priv->sarea = NULL;
+		dev_priv->sarea_priv = NULL;
+		dev->agp_buffer_map = NULL;
+
+		memset(&dev_priv->prim, 0, sizeof(dev_priv->prim));
+		dev_priv->warp_pipe = 0;
+		memset(dev_priv->warp_pipe_phys, 0, sizeof(dev_priv->warp_pipe_phys));
 
 		if (dev_priv->head != NULL) {
 			mga_freelist_cleanup(dev);
@@ -581,6 +581,7 @@ int mga_dma_init(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	drm_mga_init_t init;
+	int err;
 
 	LOCK_TEST_WITH_RETURN(dev, filp);
 
@@ -589,7 +590,11 @@ int mga_dma_init(DRM_IOCTL_ARGS)
 
 	switch (init.func) {
 	case MGA_INIT_DMA:
-		return mga_do_init_dma(dev, &init);
+		err = mga_do_init_dma(dev, &init);
+		if (err) {
+			(void) mga_do_cleanup_dma(dev);
+		}
+		return err;
 	case MGA_CLEANUP_DMA:
 		return mga_do_cleanup_dma(dev);
 	}
@@ -717,19 +722,23 @@ int mga_dma_buffers(DRM_IOCTL_ARGS)
 	return ret;
 }
 
+/**
+ * Called just before the module is unloaded.
+ */
 int mga_driver_postcleanup(drm_device_t * dev)
 {
-	int err;
-	
-	
-	err = mga_do_cleanup_dma(dev);
-	if (!err) {
-		drm_free(dev->dev_private, sizeof(drm_mga_private_t),
-			 DRM_MEM_DRIVER);
-		dev->dev_private = NULL;
-	}
+	drm_free(dev->dev_private, sizeof(drm_mga_private_t), DRM_MEM_DRIVER);
+	dev->dev_private = NULL;
+
+	return 0;
+}
 
-	return err;
+/**
+ * Called when the last opener of the device is closed.
+ */
+void mga_driver_pretakedown(drm_device_t * dev)
+{
+	mga_do_cleanup_dma(dev);
 }
 
 int mga_driver_dma_quiescent(drm_device_t * dev)