[PATCH 3/6] vfio: remove the unused mdev iommu hook

Christoph Hellwig
2021-05-10T06:54:34Z

The iommu_device field in struct mdev_device has never been used
since it was added more than 2 years ago.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/vfio/vfio_iommu_type1.c | 132 ++++++--------------------------
include/linux/mdev.h | 20 -----
2 files changed, 25 insertions(+), 127 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index a0747c35a7781e..5974a3fb2e2e12 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -113,7 +113,6 @@ struct vfio_batch {
struct vfio_group {
struct iommu_group *iommu_group;
struct list_head next;
- bool mdev_group; /* An mdev group */
bool pinned_page_dirty_scope;
};

@@ -1932,61 +1931,6 @@ static bool vfio_iommu_has_sw_msi(struct list_head *group_resv_regions,
return ret;
}

-static int vfio_mdev_attach_domain(struct device *dev, void *data)
-{
- struct mdev_device *mdev = to_mdev_device(dev);
- struct iommu_domain *domain = data;
- struct device *iommu_device;
-
- iommu_device = mdev_get_iommu_device(mdev);
- if (iommu_device) {
- if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
- return iommu_aux_attach_device(domain, iommu_device);
- else
- return iommu_attach_device(domain, iommu_device);
- }
-
- return -EINVAL;
-}
-
-static int vfio_mdev_detach_domain(struct device *dev, void *data)
-{
- struct mdev_device *mdev = to_mdev_device(dev);
- struct iommu_domain *domain = data;
- struct device *iommu_device;
-
- iommu_device = mdev_get_iommu_device(mdev);
- if (iommu_device) {
- if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
- iommu_aux_detach_device(domain, iommu_device);
- else
- iommu_detach_device(domain, iommu_device);
- }
-
- return 0;
-}
-
-static int vfio_iommu_attach_group(struct vfio_domain *domain,
- struct vfio_group *group)
-{
- if (group->mdev_group)
- return iommu_group_for_each_dev(group->iommu_group,
- domain->domain,
- vfio_mdev_attach_domain);
- else
- return iommu_attach_group(domain->domain, group->iommu_group);
-}
-
-static void vfio_iommu_detach_group(struct vfio_domain *domain,
- struct vfio_group *group)
-{
- if (group->mdev_group)
- iommu_group_for_each_dev(group->iommu_group, domain->domain,
- vfio_mdev_detach_domain);
- else
- iommu_detach_group(domain->domain, group->iommu_group);
-}
-
static bool vfio_bus_is_mdev(struct bus_type *bus)
{
struct bus_type *mdev_bus;
@@ -2001,20 +1945,6 @@ static bool vfio_bus_is_mdev(struct bus_type *bus)
return ret;
}

-static int vfio_mdev_iommu_device(struct device *dev, void *data)
-{
- struct mdev_device *mdev = to_mdev_device(dev);
- struct device **old = data, *new;
-
- new = mdev_get_iommu_device(mdev);
- if (!new || (*old && *old != new))
- return -EINVAL;
-
- *old = new;
-
- return 0;
-}
-
/*
* This is a helper function to insert an address range to iova list.
* The list is initially created with a single entry corresponding to
@@ -2275,38 +2205,24 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
goto out_free;

if (vfio_bus_is_mdev(bus)) {
- struct device *iommu_device = NULL;
-
- group->mdev_group = true;
-
- /* Determine the isolation type */
- ret = iommu_group_for_each_dev(iommu_group, &iommu_device,
- vfio_mdev_iommu_device);
- if (ret || !iommu_device) {
- if (!iommu->external_domain) {
- INIT_LIST_HEAD(&domain->group_list);
- iommu->external_domain = domain;
- vfio_update_pgsize_bitmap(iommu);
- } else {
- kfree(domain);
- }
-
- list_add(&group->next,
- &iommu->external_domain->group_list);
- /*
- * Non-iommu backed group cannot dirty memory directly,
- * it can only use interfaces that provide dirty
- * tracking.
- * The iommu scope can only be promoted with the
- * addition of a dirty tracking group.
- */
- group->pinned_page_dirty_scope = true;
- mutex_unlock(&iommu->lock);
-
- return 0;
+ if (!iommu->external_domain) {
+ INIT_LIST_HEAD(&domain->group_list);
+ iommu->external_domain = domain;
+ vfio_update_pgsize_bitmap(iommu);
+ } else {
+ kfree(domain);
}

- bus = iommu_device->bus;
+ list_add(&group->next, &iommu->external_domain->group_list);
+ /*
+ * Non-iommu backed group cannot dirty memory directly, it can
+ * only use interfaces that provide dirty tracking.
+ * The iommu scope can only be promoted with the addition of a
+ * dirty tracking group.
+ */
+ group->pinned_page_dirty_scope = true;
+ mutex_unlock(&iommu->lock);
+ return 0;
}

domain->domain = iommu_domain_alloc(bus);
@@ -2321,7 +2237,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
goto out_domain;
}

- ret = vfio_iommu_attach_group(domain, group);
+ ret = iommu_attach_group(domain->domain, group->iommu_group);
if (ret)
goto out_domain;

@@ -2388,15 +2304,17 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
list_for_each_entry(d, &iommu->domain_list, next) {
if (d->domain->ops == domain->domain->ops &&
d->prot == domain->prot) {
- vfio_iommu_detach_group(domain, group);
- if (!vfio_iommu_attach_group(d, group)) {
+ iommu_detach_group(domain->domain, group->iommu_group);
+ if (!iommu_attach_group(d->domain,
+ group->iommu_group)) {
list_add(&group->next, &d->group_list);
iommu_domain_free(domain->domain);
kfree(domain);
goto done;
}

- ret = vfio_iommu_attach_group(domain, group);
+ ret = iommu_attach_group(domain->domain,
+ group->iommu_group);
if (ret)
goto out_domain;
}
@@ -2433,7 +2351,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
return 0;

out_detach:
- vfio_iommu_detach_group(domain, group);
+ iommu_detach_group(domain->domain, group->iommu_group);
out_domain:
iommu_domain_free(domain->domain);
vfio_iommu_iova_free(&iova_copy);
@@ -2598,7 +2516,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
if (!group)
continue;

- vfio_iommu_detach_group(domain, group);
+ iommu_detach_group(domain->domain, group->iommu_group);
update_dirty_scope = !group->pinned_page_dirty_scope;
list_del(&group->next);
kfree(group);
@@ -2686,7 +2604,7 @@ static void vfio_release_domain(struct vfio_domain *domain, bool external)
list_for_each_entry_safe(group, group_tmp,
&domain->group_list, next) {
if (!external)
- vfio_iommu_detach_group(domain, group);
+ iommu_detach_group(domain->domain, group->iommu_group);
list_del(&group->next);
kfree(group);
}
diff --git a/include/linux/mdev.h b/include/linux/mdev.h
index 1fb34ea394ad46..bf818e6f8931ed 100644
--- a/include/linux/mdev.h
+++ b/include/linux/mdev.h
@@ -18,7 +18,6 @@ struct mdev_device {
void *driver_data;
struct list_head next;
struct mdev_type *type;
- struct device *iommu_device;
bool active;
};

@@ -27,25 +26,6 @@ static inline struct mdev_device *to_mdev_device(struct device *dev)
return container_of(dev, struct mdev_device, dev);
}

-/*
- * Called by the parent device driver to set the device which represents
- * this mdev in iommu protection scope. By default, the iommu device is
- * NULL, that indicates using vendor defined isolation.
- *
- * @dev: the mediated device that iommu will isolate.
- * @iommu_device: a pci device which represents the iommu for @dev.
- */
-static inline void mdev_set_iommu_device(struct mdev_device *mdev,
- struct device *iommu_device)
-{
- mdev->iommu_device = iommu_device;
-}
-
-static inline struct device *mdev_get_iommu_device(struct mdev_device *mdev)
-{
- return mdev->iommu_device;
-}
-
unsigned int mdev_get_type_group_id(struct mdev_device *mdev);
unsigned int mtype_get_type_group_id(struct mdev_type *mtype);
struct device *mtype_get_parent_dev(struct mdev_type *mtype);
--
2.30.2