From: Christian K?nig <christian.koe...@amd.com>
Avoid problems with writeback by limiting userptr to anonymous memory.
v2: add commit and code comments
Signed-off-by: Christian K?nig <christian.koenig at amd.com>
---
drivers/gpu/drm/radeon/radeon_gem.c | 3 ++-
drivers/gpu/drm/radeon/radeon_ttm.c | 10 ++++++++++
include/uapi/drm/radeon_drm.h | 1 +
3 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/radeon/radeon_gem.c
b/drivers/gpu/drm/radeon/radeon_gem.c
index 993ab22..032736b 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -290,7 +290,8 @@ int radeon_gem_userptr_ioctl(struct drm_device *dev, void
*data,
return -EACCES;
/* reject unknown flag values */
- if (args->flags & ~RADEON_GEM_USERPTR_READONLY)
+ if (args->flags & ~(RADEON_GEM_USERPTR_READONLY |
+ RADEON_GEM_USERPTR_ANONONLY))
return -EINVAL;
/* readonly pages not tested on older hardware */
diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c
b/drivers/gpu/drm/radeon/radeon_ttm.c
index 0109090..54eb7bc 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -542,6 +542,16 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_tt *ttm)
ttm->num_pages * PAGE_SIZE))
return -EFAULT;
+ if (gtt->userflags & RADEON_GEM_USERPTR_ANONONLY) {
+ /* check that we only pin down anonymous memory
+ to prevent problems with writeback */
+ unsigned long end = gtt->userptr + ttm->num_pages * PAGE_SIZE;
+ struct vm_area_struct *vma;
+ vma = find_vma(gtt->usermm, gtt->userptr);
+ if (!vma || vma->vm_file || vma->vm_end < end)
+ return -EPERM;
+ }
+
do {
unsigned num_pages = ttm->num_pages - pinned;
uint64_t userptr = gtt->userptr + pinned * PAGE_SIZE;
diff --git a/include/uapi/drm/radeon_drm.h b/include/uapi/drm/radeon_drm.h
index 3a9f209..9720e1a 100644
--- a/include/uapi/drm/radeon_drm.h
+++ b/include/uapi/drm/radeon_drm.h
@@ -816,6 +816,7 @@ struct drm_radeon_gem_create {
* perform any operation.
*/
#define RADEON_GEM_USERPTR_READONLY (1 << 0)
+#define RADEON_GEM_USERPTR_ANONONLY (1 << 1)
struct drm_radeon_gem_userptr {
uint64_t addr;
--
1.9.1
