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 <aik@xxxxxxxxx>
---
Changes:
v6:
* moved missing hunk from the next patch: tce_iommu_create_table()
would decrement locked_vm while new caller - tce_iommu_build_v2() -
will not; this adds a new return code to the DMA mapping path but
this seems to be a minor change.
---
drivers/vfio/vfio_iommu_spapr_tce.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index d0c38b2..4efd2b2 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,
@@ -588,15 +594,6 @@ static long tce_iommu_create_table(struct tce_container *container,
WARN_ON(!ret && !(*ptbl)->it_ops->free);
WARN_ON(!ret && ((*ptbl)->it_allocated_size != table_size));
- if (!ret && container->v2) {
- ret = tce_iommu_userspace_view_alloc(*ptbl);
- if (ret)
- (*ptbl)->it_ops->free(*ptbl);
- }
-
- if (ret)
- decrement_locked_vm(table_size >> PAGE_SHIFT);
-
return ret;
}
@@ -1068,10 +1065,7 @@ 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
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
