RDMA/core: Remove ucontext_lock from the uverbs_destry_ufile_hw() path

}

/*

 * Destroy the uncontext and every uobject associated with it. If called with

 * reason != RDMA_REMOVE_CLOSE this will not return until the destruction has

 * been completed and ufile->ucontext is NULL.

 * Destroy the uncontext and every uobject associated with it.

 *

 * This is internally locked and can be called in parallel from multiple

 * contexts.

void uverbs_destroy_ufile_hw(struct ib_uverbs_file *ufile,

			     enum rdma_remove_reason reason)

{

	if (reason == RDMA_REMOVE_CLOSE) {

		/*

		 * During destruction we might trigger something that

		 * synchronously calls release on any file descriptor. For

		 * this reason all paths that come from file_operations

		 * release must use try_lock. They can progress knowing that

		 * there is an ongoing uverbs_destroy_ufile_hw that will clean

		 * up the driver resources.

		 */

		if (!mutex_trylock(&ufile->ucontext_lock))

			return;

	} else {

		mutex_lock(&ufile->ucontext_lock);

	}

	down_write(&ufile->hw_destroy_rwsem);

	/*

done:

	up_write(&ufile->hw_destroy_rwsem);

	mutex_unlock(&ufile->ucontext_lock);

}

const struct uverbs_obj_type_class uverbs_fd_class = {

	if (ret)

		return ret;

	if (!down_read_trylock(&file->hw_destroy_rwsem))

		return -EIO;

	mutex_lock(&file->ucontext_lock);

	ib_dev = srcu_dereference(file->device->ib_dev,

				  &file->device->disassociate_srcu);

	smp_store_release(&file->ucontext, ucontext);

	mutex_unlock(&file->ucontext_lock);

	up_read(&file->hw_destroy_rwsem);

	return 0;

err_uobj:

err:

	mutex_unlock(&file->ucontext_lock);

	up_read(&file->hw_destroy_rwsem);

	return ret;

}