[PATCH 1/1] drm/ttm: Set memory as decrypted for ttm framebuffer mappings

From: Jiandi An
Date: Wed Aug 22 2018 - 14:58:19 EST


Framebuffer memory needs to be accessed decrypted. Ensure the
memory encryption mask is not set for the ttm framebuffer mappings.

Signed-off-by: Jiandi An <jiandi.an@xxxxxxx>
---
drivers/gpu/drm/ttm/ttm_bo_util.c | 12 +++++++++++-
drivers/gpu/drm/ttm/ttm_bo_vm.c | 6 ++++--
2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 046a6dda690a..b3f5d26f571e 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -29,6 +29,7 @@
* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
*/

+#include <asm/set_memory.h>
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_placement.h>
#include <drm/drm_vma_manager.h>
@@ -639,7 +640,11 @@ int ttm_bo_kmap(struct ttm_buffer_object *bo,
if (ret)
return ret;
if (!bo->mem.bus.is_iomem) {
- return ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
+ ret = ttm_bo_kmap_ttm(bo, start_page, num_pages, map);
+ if (!ret && sev_active())
+ set_memory_decrypted((unsigned long) map->virtual,
+ num_pages);
+ return ret;
} else {
offset = start_page << PAGE_SHIFT;
size = num_pages << PAGE_SHIFT;
@@ -661,9 +666,14 @@ void ttm_bo_kunmap(struct ttm_bo_kmap_obj *map)
iounmap(map->virtual);
break;
case ttm_bo_map_vmap:
+ if (sev_active())
+ set_memory_encrypted((unsigned long) map->virtual,
+ bo->num_pages);
vunmap(map->virtual);
break;
case ttm_bo_map_kmap:
+ if (sev_active())
+ set_memory_encrypted((unsigned long) map->virtual, 1);
kunmap(map->page);
break;
case ttm_bo_map_premapped:
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 6fe91c1b692d..211d3549fd9f 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -249,10 +249,12 @@ static vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf)
* Speculatively prefault a number of pages. Only error on
* first page.
*/
+
+ /* Mark framebuffer pages decrypted */
+ cvma.vm_page_prot = pgprot_decrypted(cvma.vm_page_prot);
+
for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
if (bo->mem.bus.is_iomem) {
- /* Iomem should not be marked encrypted */
- cvma.vm_page_prot = pgprot_decrypted(cvma.vm_page_prot);
pfn = ttm_bo_io_mem_pfn(bo, page_offset);
} else {
page = ttm->pages[page_offset];
--
2.17.1