[Intel-gfx] [PATCH] make KMS resource mappings exclusive

[Jesse Barnes]

This should help avoid problems with unsupported userspace programs or
configurations running on top of a KMS enabled driver.  Updates the
ioremap to nocache as well, since that's really what we want to track.

Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index cde5a1f..6e60671 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -932,9 +932,15 @@ static int i915_load_modeset_init(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	unsigned long agp_size, prealloc_size;
-	int fb_bar = IS_I9XX(dev) ? 2 : 0;
+	int fb_bar = IS_I9XX(dev) ? 2 : 0, mmio_bar = IS_I9XX(dev) ? 0 : 1;
 	int ret = 0;
 
+	if (pci_request_region_exclusive(dev->pdev, mmio_bar, "i915 regs")) {
+		DRM_ERROR("i915 regs already mapped, aborting\n");
+		ret = -EINVAL;
+		goto out;
+	}
+
 	dev->devname = kstrdup(DRIVER_NAME, GFP_KERNEL);
 	if (!dev->devname) {
 		ret = -ENOMEM;
@@ -1067,7 +1073,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 	base = drm_get_resource_start(dev, mmio_bar);
 	size = drm_get_resource_len(dev, mmio_bar);
 
-	dev_priv->regs = ioremap(base, size);
+	dev_priv->regs = ioremap_nocache(base, size);
 	if (!dev_priv->regs) {
 		DRM_ERROR("failed to map registers\n");
 		ret = -EIO;
@@ -1137,6 +1143,7 @@ free_priv:
 int i915_driver_unload(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
+	int mmio_bar = IS_I9XX(dev) ? 0 : 1;
 
 	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
 		io_mapping_free(dev_priv->mm.gtt_mapping);
@@ -1153,6 +1160,7 @@ int i915_driver_unload(struct drm_device *dev)
 
 	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
 		intel_modeset_cleanup(dev);
+		pci_release_region(dev->pdev, mmio_bar);
 
 		i915_gem_free_all_phys_object(dev);