vfio/spapr: Always clear TCEs before unsetting the window

The PAPR expects the TCE table to have no entries at the time of
unset window(i.e. remove-pe). The TCE clear right now is done
before freeing the iommu table. On pSeries, the unset window
makes those entries inaccessible to the OS and the H_PUT/GET calls
fail on them with H_CONSTRAINED.

On PowerNV, this has no side effect as the TCE clear can be done
before the DMA window removal as well.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/171923273535.1397.1236742071894414895.stgit@linux.ibm.com
This commit is contained in:
Shivaprasad G Bhat 2024-06-24 12:38:58 +00:00 committed by Michael Ellerman
parent aed6e4946e
commit 4ba2fdff2e

View file

@ -364,7 +364,6 @@ static void tce_iommu_release(void *iommu_data)
if (!tbl)
continue;
tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
tce_iommu_free_table(container, tbl);
}
@ -720,6 +719,8 @@ static long tce_iommu_remove_window(struct tce_container *container,
BUG_ON(!tbl->it_size);
tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
/* Detach groups from IOMMUs */
list_for_each_entry(tcegrp, &container->group_list, next) {
table_group = iommu_group_get_iommudata(tcegrp->grp);
@ -738,7 +739,6 @@ static long tce_iommu_remove_window(struct tce_container *container,
}
/* Free table */
tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
tce_iommu_free_table(container, tbl);
container->tables[num] = NULL;
@ -1197,9 +1197,14 @@ static void tce_iommu_release_ownership(struct tce_container *container,
return;
}
for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
if (container->tables[i])
for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
if (container->tables[i]) {
tce_iommu_clear(container, container->tables[i],
container->tables[i]->it_offset,
container->tables[i]->it_size);
table_group->ops->unset_window(table_group, i);
}
}
}
static long tce_iommu_take_ownership(struct tce_container *container,