From: Nicolin Chen nicolinc@nvidia.com
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@nvidia.com Signed-off-by: Yi Liu yi.l.liu@intel.com --- 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; };