[PATCH v6 06/10] iommufd: Share iommufd_hwpt_alloc with IOMMUFD_OBJ_HWPT_NESTED

Yi Liu
2023-10-24T15:10:14Z

From: Nicolin Chen <nicolinc@nvidia.com>

Allow iommufd_hwpt_alloc() to have a common routine but jump to different
allocators corresponding to different user input pt_obj types, either an
IOMMUFD_OBJ_IOAS for a PAGING hwpt or an IOMMUFD_OBJ_HWPT_PAGING as the
parent for a NESTED hwpt.

Also, move the "flags" validation to the hwpt allocator (paging), so that
later the hwpt_nested allocator can do its own separate flags validation.

Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
drivers/iommu/iommufd/hw_pagetable.c | 46 ++++++++++++++++++----------
1 file changed, 29 insertions(+), 17 deletions(-)

diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index ddce4189753f..fbe09e2473bc 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -82,6 +82,8 @@ iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
struct iommufd_device *idev, u32 flags,
bool immediate_attach)
{
+ const u32 valid_flags = IOMMU_HWPT_ALLOC_NEST_PARENT |
+ IOMMU_HWPT_ALLOC_DIRTY_TRACKING;
const struct iommu_ops *ops = dev_iommu_ops(idev->dev);
struct iommufd_hwpt_paging *hwpt_paging;
struct iommufd_hw_pagetable *hwpt;
@@ -91,6 +93,8 @@ iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,

if (flags && !ops->domain_alloc_user)
return ERR_PTR(-EOPNOTSUPP);
+ if (flags & ~valid_flags)
+ return ERR_PTR(-EOPNOTSUPP);

hwpt_paging = __iommufd_object_alloc(ictx, hwpt_paging,
IOMMUFD_OBJ_HWPT_PAGING,
@@ -169,35 +173,41 @@ iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
{
struct iommu_hwpt_alloc *cmd = ucmd->cmd;
- struct iommufd_hwpt_paging *hwpt_paging;
struct iommufd_hw_pagetable *hwpt;
+ struct iommufd_ioas *ioas = NULL;
+ struct iommufd_object *pt_obj;
struct iommufd_device *idev;
- struct iommufd_ioas *ioas;
int rc;

- if ((cmd->flags & ~(IOMMU_HWPT_ALLOC_NEST_PARENT |
- IOMMU_HWPT_ALLOC_DIRTY_TRACKING)) ||
- cmd->__reserved)
+ if (cmd->__reserved)
return -EOPNOTSUPP;

idev = iommufd_get_device(ucmd, cmd->dev_id);
if (IS_ERR(idev))
return PTR_ERR(idev);

- ioas = iommufd_get_ioas(ucmd->ictx, cmd->pt_id);
- if (IS_ERR(ioas)) {
- rc = PTR_ERR(ioas);
+ pt_obj = iommufd_get_object(ucmd->ictx, cmd->pt_id, IOMMUFD_OBJ_ANY);
+ if (IS_ERR(pt_obj)) {
+ rc = -EINVAL;
goto out_put_idev;
}

- mutex_lock(&ioas->mutex);
- hwpt_paging = iommufd_hwpt_paging_alloc(ucmd->ictx, ioas, idev,
- cmd->flags, false);
- if (IS_ERR(hwpt_paging)) {
- rc = PTR_ERR(hwpt_paging);
- goto out_unlock;
+ if (pt_obj->type == IOMMUFD_OBJ_IOAS) {
+ struct iommufd_hwpt_paging *hwpt_paging;
+
+ ioas = container_of(pt_obj, struct iommufd_ioas, obj);
+ mutex_lock(&ioas->mutex);
+ hwpt_paging = iommufd_hwpt_paging_alloc(ucmd->ictx, ioas, idev,
+ cmd->flags, false);
+ if (IS_ERR(hwpt_paging)) {
+ rc = PTR_ERR(hwpt_paging);
+ goto out_unlock;
+ }
+ hwpt = &hwpt_paging->common;
+ } else {
+ rc = -EINVAL;
+ goto out_put_pt;
}
- hwpt = &hwpt_paging->common;

cmd->out_hwpt_id = hwpt->obj.id;
rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd));
@@ -209,8 +219,10 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
out_hwpt:
iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj);
out_unlock:
- mutex_unlock(&ioas->mutex);
- iommufd_put_object(&ioas->obj);
+ if (ioas)
+ mutex_unlock(&ioas->mutex);
+out_put_pt:
+ iommufd_put_object(pt_obj);
out_put_idev:
iommufd_put_object(&idev->obj);
return rc;
--
2.34.1