[PATCH v6 04/10] iommufd/device: Wrap IOMMUFD_OBJ_HWPT_PAGING-only configurations

Yi Liu
2023-10-24T15:09:58Z

From: Jason Gunthorpe <jgg@nvidia.com>

Some of the configurations during the attach/replace() should only apply
to IOMMUFD_OBJ_HWPT_PAGING. Once IOMMUFD_OBJ_HWPT_NESTED gets introduced
in a following patch, keeping them unconditionally in the common routine
will not work.

Wrap all of those PAGING-only configurations together into helpers. Do a
hwpt_is_paging check whenever calling them or their fallback routines.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/device.c | 110 +++++++++++++++++-------
drivers/iommu/iommufd/iommufd_private.h | 5 ++
2 files changed, 85 insertions(+), 30 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index 449b64e6ef53..5bcc15cd54a1 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -325,6 +325,28 @@ static int iommufd_group_setup_msi(struct iommufd_group *igroup,
return 0;
}

+static int iommufd_hwpt_paging_attach(struct iommufd_hw_pagetable *hwpt,
+ struct iommufd_device *idev)
+{
+ int rc;
+
+ lockdep_assert_held(&idev->igroup->lock);
+
+ rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev,
+ &idev->igroup->sw_msi_start);
+ if (rc)
+ return rc;
+
+ if (list_empty(&idev->igroup->device_list)) {
+ rc = iommufd_group_setup_msi(idev->igroup, hwpt);
+ if (rc) {
+ iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
+ return rc;
+ }
+ }
+ return 0;
+}
+
int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
struct iommufd_device *idev)
{
@@ -337,10 +359,11 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
goto err_unlock;
}

- rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev,
- &idev->igroup->sw_msi_start);
- if (rc)
- goto err_unlock;
+ if (hwpt_is_paging(hwpt)) {
+ rc = iommufd_hwpt_paging_attach(hwpt, idev);
+ if (rc)
+ goto err_unlock;
+ }

/*
* Only attach to the group once for the first device that is in the
@@ -350,10 +373,6 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
* attachment.
*/
if (list_empty(&idev->igroup->device_list)) {
- rc = iommufd_group_setup_msi(idev->igroup, hwpt);
- if (rc)
- goto err_unresv;
-
rc = iommu_attach_group(hwpt->domain, idev->igroup->group);
if (rc)
goto err_unresv;
@@ -364,7 +383,8 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
mutex_unlock(&idev->igroup->lock);
return 0;
err_unresv:
- iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
+ if (hwpt_is_paging(hwpt))
+ iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
err_unlock:
mutex_unlock(&idev->igroup->lock);
return rc;
@@ -381,7 +401,8 @@ iommufd_hw_pagetable_detach(struct iommufd_device *idev)
iommu_detach_group(hwpt->domain, idev->igroup->group);
idev->igroup->hwpt = NULL;
}
- iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
+ if (hwpt_is_paging(hwpt))
+ iopt_remove_reserved_iova(&hwpt->ioas->iopt, idev->dev);
mutex_unlock(&idev->igroup->lock);

/* Caller must destroy hwpt */
@@ -400,13 +421,51 @@ iommufd_device_do_attach(struct iommufd_device *idev,
return NULL;
}

+static void iommufd_group_remove_reserved_iova(struct iommufd_group *igroup,
+ struct iommufd_hw_pagetable *hwpt)
+{
+ struct iommufd_device *cur;
+
+ lockdep_assert_held(&igroup->lock);
+
+ list_for_each_entry(cur, &igroup->device_list, group_item)
+ iopt_remove_reserved_iova(&hwpt->ioas->iopt, cur->dev);
+}
+
+static int iommufd_group_do_replace_paging(struct iommufd_group *igroup,
+ struct iommufd_hw_pagetable *hwpt)
+{
+ struct iommufd_hw_pagetable *old_hwpt = igroup->hwpt;
+ struct iommufd_device *cur;
+ int rc;
+
+ lockdep_assert_held(&igroup->lock);
+
+ if (hwpt_is_paging(old_hwpt) && hwpt->ioas != old_hwpt->ioas) {
+ list_for_each_entry(cur, &igroup->device_list, group_item) {
+ rc = iopt_table_enforce_dev_resv_regions(
+ &hwpt->ioas->iopt, cur->dev, NULL);
+ if (rc)
+ goto err_unresv;
+ }
+ }
+
+ rc = iommufd_group_setup_msi(igroup, hwpt);
+ if (rc)
+ goto err_unresv;
+ return 0;
+
+err_unresv:
+ iommufd_group_remove_reserved_iova(igroup, hwpt);
+ return rc;
+}
+
static struct iommufd_hw_pagetable *
iommufd_device_do_replace(struct iommufd_device *idev,
struct iommufd_hw_pagetable *hwpt)
{
struct iommufd_group *igroup = idev->igroup;
struct iommufd_hw_pagetable *old_hwpt;
- struct iommufd_device *cur;
unsigned int num_devices;
int rc;

@@ -422,29 +481,20 @@ iommufd_device_do_replace(struct iommufd_device *idev,
return NULL;
}

- old_hwpt = igroup->hwpt;
- if (hwpt->ioas != old_hwpt->ioas) {
- list_for_each_entry(cur, &igroup->device_list, group_item) {
- rc = iopt_table_enforce_dev_resv_regions(
- &hwpt->ioas->iopt, cur->dev, NULL);
- if (rc)
- goto err_unresv;
- }
+ if (hwpt_is_paging(hwpt)) {
+ rc = iommufd_group_do_replace_paging(igroup, hwpt);
+ if (rc)
+ goto err_unlock;
}

- rc = iommufd_group_setup_msi(idev->igroup, hwpt);
- if (rc)
- goto err_unresv;
-
rc = iommu_group_replace_domain(igroup->group, hwpt->domain);
if (rc)
goto err_unresv;

- if (hwpt->ioas != old_hwpt->ioas) {
- list_for_each_entry(cur, &igroup->device_list, group_item)
- iopt_remove_reserved_iova(&old_hwpt->ioas->iopt,
- cur->dev);
- }
+ old_hwpt = igroup->hwpt;
+ if (hwpt_is_paging(old_hwpt) &&
+ (!hwpt_is_paging(hwpt) || hwpt->ioas != old_hwpt->ioas))
+ iommufd_group_remove_reserved_iova(igroup, old_hwpt);

igroup->hwpt = hwpt;

@@ -462,8 +512,8 @@ iommufd_device_do_replace(struct iommufd_device *idev,
/* Caller must destroy old_hwpt */
return old_hwpt;
err_unresv:
- list_for_each_entry(cur, &igroup->device_list, group_item)
- iopt_remove_reserved_iova(&hwpt->ioas->iopt, cur->dev);
+ if (hwpt_is_paging(hwpt))
+ iommufd_group_remove_reserved_iova(igroup, hwpt);
err_unlock:
mutex_unlock(&idev->igroup->lock);
return ERR_PTR(rc);
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 70bebad63a74..776dd41c077f 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -252,6 +252,11 @@ struct iommufd_hw_pagetable {
struct list_head hwpt_item;
};

+static inline bool hwpt_is_paging(struct iommufd_hw_pagetable *hwpt)
+{
+ return hwpt->obj.type == IOMMUFD_OBJ_HWPT_PAGING;
+}
+
static inline struct iommufd_hw_pagetable *
iommufd_get_hwpt(struct iommufd_ucmd *ucmd, u32 id)
{
--
2.34.1