I didn't fix this in the earlier patch -- it would have broken the
build due to the now-deleted garbage in drm_os_linux.h.
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Signed-off-by: Andy Lutomirski <luto at amacapital.net>
---
drivers/gpu/drm/drm_bufs.c | 9 +++++++++
drivers/gpu/drm/drm_ioctl.c | 15 ++++++++++++++-
2 files changed, 23 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_bufs.c b/drivers/gpu/drm/drm_bufs.c
index 0190fce..5a4dbb4 100644
--- a/drivers/gpu/drm/drm_bufs.c
+++ b/drivers/gpu/drm/drm_bufs.c
@@ -414,6 +414,15 @@ int drm_addmap_ioctl(struct drm_device *dev, void *data,
/* avoid a warning on 64-bit, this casting isn't very nice, but the API
is set so too late */
map->handle = (void *)(unsigned long)maplist->user_token;
+
+ /*
+ * It appears that there are no users of this value whatsoever --
+ * drmAddMap just discards it. Let's not encourage its use.
+ * (Keeping drm_addmap_core's returned mtrr value would be wrong --
+ * it's not a real mtrr index anymore.)
+ */
+ map->mtrr = -1;
+
return 0;
}
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index e77bd8b..ffd7a7b 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -38,6 +38,9 @@
#include <linux/pci.h>
#include <linux/export.h>
+#ifdef CONFIG_X86
+#include <asm/mtrr.h>
+#endif
/**
* Get the bus id.
@@ -181,7 +184,17 @@ int drm_getmap(struct drm_device *dev, void *data,
map->type = r_list->map->type;
map->flags = r_list->map->flags;
map->handle = (void *)(unsigned long) r_list->user_token;
- map->mtrr = r_list->map->mtrr;
+
+#ifdef CONFIG_X86
+ /*
+ * There appears to be exactly one user of the mtrr index: dritest.
+ * It's easy enough to keep it working on non-PAT systems.
+ */
+ map->mtrr = phys_wc_to_mtrr_index(r_list->map->mtrr);
+#else
+ map->mtrr = -1;
+#endif
+
mutex_unlock(&dev->struct_mutex);
return 0;
--
1.8.1.4
