Commit e1ea9d30 authored by Yi Liu's avatar Yi Liu Committed by Jason Gunthorpe
Browse files

iommu: Store either domain or handle in group->pasid_array 

iommu_attach_device_pasid() only stores handle to group->pasid_array
when there is a valid handle input. However, it makes the
iommu_attach_device_pasid() unable to detect if the pasid has been
attached or not previously.

To be complete, let the iommu_attach_device_pasid() store the domain
to group->pasid_array if no valid handle. The other users of the
group->pasid_array should be updated to be consistent. e.g. the
iommu_attach_group_handle() and iommu_replace_group_handle().

Link: https://patch.msgid.link/r/20250226011849.5102-4-yi.l.liu@intel.com


Suggested-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarYi Liu <yi.l.liu@intel.com>
Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 473ec072

drivers/iommu/iommu.c

+31 −12
Original line number Diff line number Diff line
@@ -45,6 +45,9 @@ static unsigned int iommu_def_domain_type __read_mostly; 
static bool iommu_dma_strict __read_mostly = IS_ENABLED(CONFIG_IOMMU_DEFAULT_DMA_STRICT);

static u32 iommu_cmd_line __read_mostly;



/* Tags used with xa_tag_pointer() in group->pasid_array */

enum { IOMMU_PASID_ARRAY_DOMAIN = 0, IOMMU_PASID_ARRAY_HANDLE = 1 };



struct iommu_group {

	struct kobject kobj;

	struct kobject *devices_kobj;
@@ -2147,6 +2150,17 @@ struct iommu_domain *iommu_get_dma_domain(struct device *dev) 
	return dev->iommu_group->default_domain;

}



static void *iommu_make_pasid_array_entry(struct iommu_domain *domain,

					  struct iommu_attach_handle *handle)

{

	if (handle) {

		handle->domain = domain;

		return xa_tag_pointer(handle, IOMMU_PASID_ARRAY_HANDLE);

	}



	return xa_tag_pointer(domain, IOMMU_PASID_ARRAY_DOMAIN);

}



static int __iommu_attach_group(struct iommu_domain *domain,

				struct iommu_group *group)

{
@@ -3348,6 +3362,7 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, 
	struct iommu_group *group = dev->iommu_group;

	struct group_device *device;

	const struct iommu_ops *ops;

	void *entry;

	int ret;



	if (!group)
@@ -3371,10 +3386,9 @@ int iommu_attach_device_pasid(struct iommu_domain *domain, 
		}

	}



	if (handle)

		handle->domain = domain;

	entry = iommu_make_pasid_array_entry(domain, handle);



	ret = xa_insert(&group->pasid_array, pasid, handle, GFP_KERNEL);

	ret = xa_insert(&group->pasid_array, pasid, entry, GFP_KERNEL);

	if (ret)

		goto out_unlock;
@@ -3454,13 +3468,17 @@ struct iommu_attach_handle * 
iommu_attach_handle_get(struct iommu_group *group, ioasid_t pasid, unsigned int type)

{

	struct iommu_attach_handle *handle;

	void *entry;



	xa_lock(&group->pasid_array);

	handle = xa_load(&group->pasid_array, pasid);

	if (!handle)

	entry = xa_load(&group->pasid_array, pasid);

	if (!entry || xa_pointer_tag(entry) != IOMMU_PASID_ARRAY_HANDLE) {

		handle = ERR_PTR(-ENOENT);

	else if (type && handle->domain->type != type)

	} else {

		handle = xa_untag_pointer(entry);

		if (type && handle->domain->type != type)

			handle = ERR_PTR(-EBUSY);

	}

	xa_unlock(&group->pasid_array);



	return handle;
@@ -3483,14 +3501,15 @@ int iommu_attach_group_handle(struct iommu_domain *domain, 
			      struct iommu_group *group,

			      struct iommu_attach_handle *handle)

{

	void *entry;

	int ret;



	if (!handle)

		return -EINVAL;



	mutex_lock(&group->mutex);

	handle->domain = domain;

	ret = xa_insert(&group->pasid_array, IOMMU_NO_PASID, handle, GFP_KERNEL);

	entry = iommu_make_pasid_array_entry(domain, handle);

	ret = xa_insert(&group->pasid_array, IOMMU_NO_PASID, entry, GFP_KERNEL);

	if (ret)

		goto err_unlock;
@@ -3543,14 +3562,14 @@ int iommu_replace_group_handle(struct iommu_group *group, 
			       struct iommu_domain *new_domain,

			       struct iommu_attach_handle *handle)

{

	void *curr;

	void *curr, *entry;

	int ret;



	if (!new_domain || !handle)

		return -EINVAL;



	mutex_lock(&group->mutex);

	handle->domain = new_domain;

	entry = iommu_make_pasid_array_entry(new_domain, handle);

	ret = xa_reserve(&group->pasid_array, IOMMU_NO_PASID, GFP_KERNEL);

	if (ret)

		goto err_unlock;
@@ -3559,7 +3578,7 @@ int iommu_replace_group_handle(struct iommu_group *group, 
	if (ret)

		goto err_release;



	curr = xa_store(&group->pasid_array, IOMMU_NO_PASID, handle, GFP_KERNEL);

	curr = xa_store(&group->pasid_array, IOMMU_NO_PASID, entry, GFP_KERNEL);

	WARN_ON(xa_is_err(curr));



	mutex_unlock(&group->mutex);