drm/etnaviv: trick drm_mm into giving out a low IOVA
After rollover of the IOVA space, we want to get a low IOVA address, otherwise the the games we play by remembering the last IOVA are pointless. When we search for a free hole with DRM_MM_SEARCH_DEFAULT, drm_mm will pop the next entry from the free holes stack, which will likely be a high IOVA. By using DRM_MM_SEARCH_BELOW we can trick drm_mm into reversing the search and provide us with a low IOVA. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Reviewed-by: Wladimir van der Laan <laanwj@gmail.com>
This commit is contained in:
parent
7ce7d89f48
commit
3546fb0cda
|
@ -116,9 +116,14 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu *mmu,
|
|||
struct list_head list;
|
||||
bool found;
|
||||
|
||||
/*
|
||||
* XXX: The DRM_MM_SEARCH_BELOW is really a hack to trick
|
||||
* drm_mm into giving out a low IOVA after address space
|
||||
* rollover. This needs a proper fix.
|
||||
*/
|
||||
ret = drm_mm_insert_node_in_range(&mmu->mm, node,
|
||||
size, 0, mmu->last_iova, ~0UL,
|
||||
DRM_MM_SEARCH_DEFAULT);
|
||||
mmu->last_iova ? DRM_MM_SEARCH_DEFAULT : DRM_MM_SEARCH_BELOW);
|
||||
|
||||
if (ret != -ENOSPC)
|
||||
break;
|
||||
|
|
Loading…
Reference in a new issue