The iommu_table struct manages a hardware TCE table and a vmalloc'd
table with corresponding userspace addresses. Both are allocated when
the default DMA window is created and this happens when the very first
group is attached to a container.
As we are going to allow the userspace to configure container in one
memory context and pas container fd to another, we have to postpones
such allocations till a container fd is passed to the destination
user process so we would account locked memory limit against the actual
container user constrainsts.
This postpones the it_userspace array allocation till it is used first
time for mapping. The unmapping patch already checks if the array is
allocated.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
drivers/vfio/vfio_iommu_spapr_tce.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c
b/drivers/vfio/vfio_iommu_spapr_tce.c
index d0c38b2..442baac 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -515,6 +515,12 @@ static long tce_iommu_build_v2(struct tce_container
*container,
unsigned long hpa;
enum dma_data_direction dirtmp;
+ if (!tbl->it_userspace) {
+ ret = tce_iommu_userspace_view_alloc(tbl);
+ if (ret)
+ return ret;
+ }
+
for (i = 0; i < pages; ++i) {
struct mm_iommu_table_group_mem_t *mem = NULL;
unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl,
@@ -1068,10 +1074,7 @@ static int tce_iommu_take_ownership(struct tce_container
*container,
if (!tbl || !tbl->it_map)
continue;
- rc = tce_iommu_userspace_view_alloc(tbl);
- if (!rc)
- rc = iommu_take_ownership(tbl);
-
+ rc = iommu_take_ownership(tbl);
if (rc) {
for (j = 0; j < i; ++j)
iommu_release_ownership(
--
2.5.0.rc3
