From: Nicolin Chen <nicolinc@xxxxxxxxxx>
Add a parent hw_pagetable pointer for user-managed hw_pagetables. Similar
to the ioas->mutex, add another mutex in the kernel-managed hw_pagetable
to serialize associating user-managed hw_pagetable allocations. Then, add
user_managed flag too in the struct to ease identifying a HWPT.
Also, add a new allocator iommufd_user_managed_hwpt_alloc() and two pairs
of cleanup functions iommufd_user_managed_hwpt_destroy/abort().
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
drivers/iommu/iommufd/hw_pagetable.c | 112 +++++++++++++++++++++++-
drivers/iommu/iommufd/iommufd_private.h | 6 ++
2 files changed, 117 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index b2af68776877..dc3e11a23acf 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -8,6 +8,17 @@
#include "../iommu-priv.h"
#include "iommufd_private.h"
+static void iommufd_user_managed_hwpt_destroy(struct iommufd_object *obj)
+{
+ struct iommufd_hw_pagetable *hwpt =
+ container_of(obj, struct iommufd_hw_pagetable, obj);
+
+ if (hwpt->domain)
+ iommu_domain_free(hwpt->domain);
+
+ refcount_dec(&hwpt->parent->obj.users);
+}
+
static void iommufd_kernel_managed_hwpt_destroy(struct iommufd_object *obj)
{
struct iommufd_hw_pagetable *hwpt =
@@ -32,6 +43,17 @@ void iommufd_hw_pagetable_destroy(struct iommufd_object *obj)
container_of(obj, struct iommufd_hw_pagetable, obj)->destroy(obj);
}
+static void iommufd_user_managed_hwpt_abort(struct iommufd_object *obj)
+{
+ struct iommufd_hw_pagetable *hwpt =
+ container_of(obj, struct iommufd_hw_pagetable, obj);
+
+ /* The parent->mutex must be held until finalize is called. */
+ lockdep_assert_held(&hwpt->parent->mutex);
+
+ iommufd_hw_pagetable_destroy(obj);
+}
+
static void iommufd_kernel_managed_hwpt_abort(struct iommufd_object *obj)
{
struct iommufd_hw_pagetable *hwpt =
@@ -52,6 +74,82 @@ void iommufd_hw_pagetable_abort(struct iommufd_object *obj)
container_of(obj, struct iommufd_hw_pagetable, obj)->abort(obj);
}
+/**
+ * iommufd_user_managed_hwpt_alloc() - Get a user-managed hw_pagetable
+ * @ictx: iommufd context
+ * @pt_obj: Parent object to an HWPT to associate the domain with
+ * @idev: Device to get an iommu_domain for
+ * @flags: Flags from userspace
+ * @hwpt_type: Requested type of hw_pagetable
+ * @user_data: user_data pointer
+ * @dummy: never used
+ *
+ * Allocate a new iommu_domain (must be IOMMU_DOMAIN_NESTED) and return it as
+ * a user-managed hw_pagetable.
+ */
+static struct iommufd_hw_pagetable *
+iommufd_user_managed_hwpt_alloc(struct iommufd_ctx *ictx,
+ struct iommufd_object *pt_obj,
+ struct iommufd_device *idev,
+ u32 flags,
+ enum iommu_hwpt_type hwpt_type,
+ struct iommu_user_data *user_data,
+ bool dummy)
+{
+ struct iommufd_hw_pagetable *parent =
+ container_of(pt_obj, struct iommufd_hw_pagetable, obj);
+ const struct iommu_ops *ops = dev_iommu_ops(idev->dev);
+ struct iommufd_hw_pagetable *hwpt;
+ int rc;
+
+ if (!user_data)
+ return ERR_PTR(-EINVAL);
+ if (parent->auto_domain)
+ return ERR_PTR(-EINVAL);
+ if (!parent->nest_parent)
+ return ERR_PTR(-EINVAL);
+ if (hwpt_type == IOMMU_HWPT_TYPE_DEFAULT)
+ return ERR_PTR(-EINVAL);
+
+ if (!ops->domain_alloc_user)
+ return ERR_PTR(-EOPNOTSUPP);
+
+ lockdep_assert_held(&parent->mutex);
+
+ hwpt = iommufd_object_alloc(ictx, hwpt, IOMMUFD_OBJ_HW_PAGETABLE);
+ if (IS_ERR(hwpt))
+ return hwpt;
+
+ refcount_inc(&parent->obj.users);
+ hwpt->parent = parent;
+ hwpt->user_managed = true;
+ hwpt->abort = iommufd_user_managed_hwpt_abort;
+ hwpt->destroy = iommufd_user_managed_hwpt_destroy;
+
+ hwpt->domain = ops->domain_alloc_user(idev->dev, flags, hwpt_type,
+ parent->domain, user_data);
+ if (IS_ERR(hwpt->domain)) {
+ rc = PTR_ERR(hwpt->domain);
+ hwpt->domain = NULL;
+ goto out_abort;
+ }
+
+ if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED)) {
+ rc = -EINVAL;
+ goto out_abort;
+ }
+ /* Driver is buggy by missing cache_invalidate_user in domain_ops */
+ if (WARN_ON_ONCE(!hwpt->domain->ops->cache_invalidate_user)) {
+ rc = -EINVAL;
+ goto out_abort;
+ }
+ return hwpt;
+
+out_abort:
+ iommufd_object_abort_and_destroy(ictx, &hwpt->obj);
+ return ERR_PTR(rc);
+}
+
int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
{
if (hwpt->enforce_cache_coherency)
@@ -112,10 +210,12 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx,
if (IS_ERR(hwpt))
return hwpt;
+ mutex_init(&hwpt->mutex);
INIT_LIST_HEAD(&hwpt->hwpt_item);
/* Pairs with iommufd_hw_pagetable_destroy() */
refcount_inc(&ioas->obj.users);
hwpt->ioas = ioas;
+ hwpt->nest_parent = flags & IOMMU_HWPT_ALLOC_NEST_PARENT;
hwpt->abort = iommufd_kernel_managed_hwpt_abort;
hwpt->destroy = iommufd_kernel_managed_hwpt_destroy;
@@ -194,8 +294,8 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
u32 flags, enum iommu_hwpt_type type,
struct iommu_user_data *user_data,
bool flag);
+ struct iommufd_hw_pagetable *hwpt, *parent;
struct iommu_hwpt_alloc *cmd = ucmd->cmd;
- struct iommufd_hw_pagetable *hwpt;
struct iommufd_object *pt_obj;
struct iommufd_device *idev;
struct iommufd_ioas *ioas;
@@ -221,6 +321,16 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
mutex = &ioas->mutex;
alloc_fn = iommufd_hw_pagetable_alloc;
break;
+ case IOMMUFD_OBJ_HW_PAGETABLE:
+ parent = container_of(pt_obj, struct iommufd_hw_pagetable, obj);
+ /* No user-managed HWPT on top of an user-managed one */
+ if (parent->user_managed) {
+ rc = -EINVAL;
+ goto out_put_pt;
+ }
+ mutex = &parent->mutex;
+ alloc_fn = iommufd_user_managed_hwpt_alloc;
+ break;
default:
rc = -EINVAL;
goto out_put_pt;
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index e4d06ae6b0c5..34940596c2c2 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -237,12 +237,18 @@ struct iommufd_hw_pagetable {
void (*abort)(struct iommufd_object *obj);
void (*destroy)(struct iommufd_object *obj);
+ bool user_managed : 1;
union {
+ struct { /* user-managed */
+ struct iommufd_hw_pagetable *parent;
+ };
struct { /* kernel-managed */
struct iommufd_ioas *ioas;
+ struct mutex mutex;
bool auto_domain : 1;
bool enforce_cache_coherency : 1;
bool msi_cookie : 1;
+ bool nest_parent : 1;
/* Head at iommufd_ioas::hwpt_list */
struct list_head hwpt_item;
};
--
2.34.1
