Since commit 0286300e6045 ("iommu: iommu_group_claim_dma_owner() must
always assign a domain") s390-iommu will get called to allocate multiple
unmanaged iommu domains for a vfio-pci device -- however the current
s390-iommu logic tolerates only one. Recognize that multiple domains can
be allocated and handle switching between DMA or different iommu domain
tables during attach_dev.
Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
---
drivers/iommu/s390-iommu.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index 3833e86c6e7b..c898bcbbce11 100644
--- a/drivers/iommu/s390-iommu.c
+++ b/drivers/iommu/s390-iommu.c
@@ -99,7 +99,7 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
if (!domain_device)
return -ENOMEM;
- if (zdev->dma_table) {
+ if (zdev->dma_table && !zdev->s390_domain) {
cc = zpci_dma_exit_device(zdev);
if (cc) {
rc = -EIO;
@@ -107,6 +107,9 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
}
}
+ if (zdev->s390_domain)
+ zpci_unregister_ioat(zdev, 0);
+
zdev->dma_table = s390_domain->dma_table;
cc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
virt_to_phys(zdev->dma_table));
@@ -136,7 +139,13 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
return 0;
out_restore:
- zpci_dma_init_device(zdev);
+ if (!zdev->s390_domain) {
+ zpci_dma_init_device(zdev);
+ } else {
+ zdev->dma_table = zdev->s390_domain->dma_table;
+ zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+ virt_to_phys(zdev->dma_table));
+ }
out_free:
kfree(domain_device);
@@ -167,7 +176,7 @@ static void s390_iommu_detach_device(struct iommu_domain *domain,
}
spin_unlock_irqrestore(&s390_domain->list_lock, flags);
- if (found) {
+ if (found && (zdev->s390_domain == s390_domain)) {
zdev->s390_domain = NULL;
zpci_unregister_ioat(zdev, 0);
zpci_dma_init_device(zdev);
--
2.27.0
