Commit 3546fb0c authored by Lucas Stach's avatar Lucas Stach
Browse files

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: default avatarLucas Stach <>
Reviewed-by: default avatarWladimir van der Laan <>
parent 7ce7d89f
......@@ -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,
if (ret != -ENOSPC)
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