On 04/29/2015 12:16 PM, David Gibson wrote:
On Sat, Apr 25, 2015 at 10:14:33PM +1000, Alexey Kardashevskiy wrote:
This is to make extended ownership and multiple groups support patches
simpler for review.
This should cause no behavioural change.
Um.. this doesn't appear to be true. Previously removing a group from
an enabled container would fail with EBUSY, now it forces a disable.
This is the original tce_iommu_detach_group() where I cannot find EBUSY you
are referring to; it did and does enforce disable. What do I miss here?
static void tce_iommu_detach_group(void *iommu_data,
struct iommu_group *iommu_group)
{
struct tce_container *container = iommu_data;
struct iommu_table *tbl = iommu_group_get_iommudata(iommu_group);
BUG_ON(!tbl);
mutex_lock(&container->lock);
if (tbl != container->tbl) {
pr_warn("tce_vfio: detaching group #%u, expected group is
#%u\n",
iommu_group_id(iommu_group),
iommu_group_id(tbl->it_group));
} else {
if (container->enabled) {
pr_warn("tce_vfio: detaching group #%u from
enabled container, forcing disable\n",
iommu_group_id(tbl->it_group));
tce_iommu_disable(container);
}
/* pr_debug("tce_vfio: detaching group #%u from iommu %p\n",
iommu_group_id(iommu_group), iommu_group); */
container->tbl = NULL;
tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
iommu_release_ownership(tbl);
}
mutex_unlock(&container->lock);
}
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.william...@redhat.com>
Reviewed-by: David Gibson <da...@gibson.dropbear.id.au>
---
drivers/vfio/vfio_iommu_spapr_tce.c | 40 ++++++++++++++++++++++---------------
1 file changed, 24 insertions(+), 16 deletions(-)
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c
b/drivers/vfio/vfio_iommu_spapr_tce.c
index 115d5e6..0fbe03e 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -460,16 +460,21 @@ static int tce_iommu_attach_group(void *iommu_data,
iommu_group_id(container->tbl->it_group),
iommu_group_id(iommu_group));
ret = -EBUSY;
- } else if (container->enabled) {
+ goto unlock_exit;
+ }
+
+ if (container->enabled) {
pr_err("tce_vfio: attaching group #%u to enabled container\n",
iommu_group_id(iommu_group));
ret = -EBUSY;
- } else {
- ret = iommu_take_ownership(tbl);
- if (!ret)
- container->tbl = tbl;
+ goto unlock_exit;
}
+ ret = iommu_take_ownership(tbl);
+ if (!ret)
+ container->tbl = tbl;
+
+unlock_exit:
mutex_unlock(&container->lock);
return ret;
@@ -487,19 +492,22 @@ static void tce_iommu_detach_group(void *iommu_data,
pr_warn("tce_vfio: detaching group #%u, expected group is
#%u\n",
iommu_group_id(iommu_group),
iommu_group_id(tbl->it_group));
- } else {
- if (container->enabled) {
- pr_warn("tce_vfio: detaching group #%u from enabled
container, forcing disable\n",
- iommu_group_id(tbl->it_group));
- tce_iommu_disable(container);
- }
+ goto unlock_exit;
+ }
- /* pr_debug("tce_vfio: detaching group #%u from iommu %p\n",
- iommu_group_id(iommu_group), iommu_group); */
- container->tbl = NULL;
- tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
- iommu_release_ownership(tbl);
+ if (container->enabled) {
+ pr_warn("tce_vfio: detaching group #%u from enabled container,
forcing disable\n",
+ iommu_group_id(tbl->it_group));
+ tce_iommu_disable(container);
}
+
+ /* pr_debug("tce_vfio: detaching group #%u from iommu %p\n",
+ iommu_group_id(iommu_group), iommu_group); */
+ container->tbl = NULL;
+ tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
+ iommu_release_ownership(tbl);
+
+unlock_exit:
mutex_unlock(&container->lock);
}
--
Alexey
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@lists.ozlabs.org
https://lists.ozlabs.org/listinfo/linuxppc-dev
