On Tue, 7 Feb 2017 17:26:57 +1100 Alexey Kardashevskiy <aik@xxxxxxxxx> wrote: > If a container already has a group attached, attaching a new group > should just program already created IOMMU tables to the hardware via > the iommu_table_group_ops::set_window() callback. > > However 6f01cc692 "vfio/spapr: Add a helper to create default DMA window" > did not just simplify the code but also removed the set_window() calls > in the case of attaching groups to a container which already has tables > so it broke VFIO PCI hotplug. > > This reverts set_window() bits in tce_iommu_take_ownership_ddw(). > > Fixes: 6f01cc692 See Documentation/process/submitting-patches.rst for the expected format here, 12 char SHA-1 + --oneline summary. > Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx> > --- > drivers/vfio/vfio_iommu_spapr_tce.c | 21 +++++++++++++++++++++ > 1 file changed, 21 insertions(+) > > diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c > index 7690e5bf3cf1..14c62a8495a2 100644 > --- a/drivers/vfio/vfio_iommu_spapr_tce.c > +++ b/drivers/vfio/vfio_iommu_spapr_tce.c > @@ -1245,6 +1245,8 @@ static void tce_iommu_release_ownership_ddw(struct tce_container *container, > static long tce_iommu_take_ownership_ddw(struct tce_container *container, > struct iommu_table_group *table_group) > { > + long i, ret = 0; > + > if (!table_group->ops->create_table || !table_group->ops->set_window || > !table_group->ops->release_ownership) { > WARN_ON_ONCE(1); > @@ -1253,7 +1255,26 @@ static long tce_iommu_take_ownership_ddw(struct tce_container *container, > > table_group->ops->take_ownership(table_group); > > + /* Set all windows to the new group */ > + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { > + struct iommu_table *tbl = container->tables[i]; checkpatch wants a blank line here. > + if (!tbl) > + continue; > + > + ret = table_group->ops->set_window(table_group, i, tbl); > + if (ret) > + goto release_exit; > + } > + > return 0; > + > +release_exit: > + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) > + table_group->ops->unset_window(table_group, i); > + > + table_group->ops->release_ownership(table_group); > + > + return ret; > } > > static int tce_iommu_attach_group(void *iommu_data, I've fixed these as shown below. David, please review/ack as well and I'll send a pull for v4.10. Thanks, Alex commit c019167838156a2efcc60a15fa4207710bac6e82 Author: Alexey Kardashevskiy <aik@xxxxxxxxx> Date: Tue Feb 7 17:26:57 2017 +1100 vfio/spapr_tce: Set window when adding additional groups to container If a container already has a group attached, attaching a new group should just program already created IOMMU tables to the hardware via the iommu_table_group_ops::set_window() callback. However commit 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") did not just simplify the code but also removed the set_window() calls in the case of attaching groups to a container which already has tables so it broke VFIO PCI hotplug. This reverts set_window() bits in tce_iommu_take_ownership_ddw(). Fixes: 6f01cc692a16 ("vfio/spapr: Add a helper to create default DMA window") Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index 7690e5bf3cf1..59b3f62a2d64 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1245,6 +1245,8 @@ static void tce_iommu_release_ownership_ddw(struct tce_container *container, static long tce_iommu_take_ownership_ddw(struct tce_container *container, struct iommu_table_group *table_group) { + long i, ret = 0; + if (!table_group->ops->create_table || !table_group->ops->set_window || !table_group->ops->release_ownership) { WARN_ON_ONCE(1); @@ -1253,7 +1255,27 @@ static long tce_iommu_take_ownership_ddw(struct tce_container *container, table_group->ops->take_ownership(table_group); + /* Set all windows to the new group */ + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) { + struct iommu_table *tbl = container->tables[i]; + + if (!tbl) + continue; + + ret = table_group->ops->set_window(table_group, i, tbl); + if (ret) + goto release_exit; + } + return 0; + +release_exit: + for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) + table_group->ops->unset_window(table_group, i); + + table_group->ops->release_ownership(table_group); + + return ret; } static int tce_iommu_attach_group(void *iommu_data,