1 // SPDX-License-Identifier: GPL-2.0
22  * struct ioasid_allocator_data - Internal data structure to hold information
25  * - Default allocator always has its own XArray to track the IOASIDs allocated.
26  * - Custom allocators may share allocation helpers with different private data.
27  *   Custom allocators that share the same helper functions also share the same
34  * 3. When all custom allocators sharing the same helper functions are
38  *    functions, outstanding IOASIDs are preserved.
42  * @ops:	allocator helper functions and its data
62 static ioasid_t default_alloc(ioasid_t min, ioasid_t max, void *opaque);
78 static ioasid_t default_alloc(ioasid_t min, ioasid_t max, void *opaque)  in default_alloc()  argument
82 	if (xa_alloc(&default_allocator.xa, &id, opaque, XA_LIMIT(min, max), GFP_ATOMIC)) {  in default_alloc()
83 		pr_err("Failed to alloc ioasid from %d to %d\n", min, max);  in default_alloc()
98 /* Allocate and initialize a new custom allocator with its helper functions */
107 	xa_init_flags(&ia_data->xa, XA_FLAGS_ALLOC);  in ioasid_alloc_allocator()
108 	INIT_LIST_HEAD(&ia_data->slist);  in ioasid_alloc_allocator()
109 	ia_data->flags |= IOASID_ALLOCATOR_CUSTOM;  in ioasid_alloc_allocator()
110 	ia_data->ops = ops;  in ioasid_alloc_allocator()
113 	list_add_tail(&ops->list, &ia_data->slist);  in ioasid_alloc_allocator()
120 	return (a->free == b->free) && (a->alloc == b->alloc);  in use_same_ops()
124  * ioasid_register_allocator - register a custom allocator
149 		ret = -ENOMEM;  in ioasid_register_allocator()
161 		if (xa_empty(&active_allocator->xa)) {  in ioasid_register_allocator()
163 			list_add_tail(&ia_data->list, &allocators_list);  in ioasid_register_allocator()
167 		ret = -EAGAIN;  in ioasid_register_allocator()
173 		if (pallocator->ops == ops) {  in ioasid_register_allocator()
175 			ret = -EEXIST;  in ioasid_register_allocator()
177 		} else if (use_same_ops(pallocator->ops, ops)) {  in ioasid_register_allocator()
183 			list_add_tail(&ops->list, &pallocator->slist);  in ioasid_register_allocator()
187 	list_add_tail(&ia_data->list, &allocators_list);  in ioasid_register_allocator()
200  * ioasid_unregister_allocator - Remove a custom IOASID allocator ops
219 		if (!use_same_ops(pallocator->ops, ops))  in ioasid_unregister_allocator()
222 		if (list_is_singular(&pallocator->slist)) {  in ioasid_unregister_allocator()
223 			/* No shared helper functions */  in ioasid_unregister_allocator()
224 			list_del(&pallocator->list);  in ioasid_unregister_allocator()
230 			WARN_ON(!xa_empty(&pallocator->xa));  in ioasid_unregister_allocator()
247 		list_for_each_entry(sops, &pallocator->slist, list) {  in ioasid_unregister_allocator()
249 				list_del(&ops->list);  in ioasid_unregister_allocator()
262  * ioasid_set_data - Set private data for an allocated ioasid
275 	ioasid_data = xa_load(&active_allocator->xa, ioasid);  in ioasid_set_data()
277 		rcu_assign_pointer(ioasid_data->private, data);  in ioasid_set_data()
279 		ret = -ENOENT;  in ioasid_set_data()
294  * ioasid_alloc - Allocate an IOASID
297  * @max: the maximum ID (inclusive)
300  * Allocate an ID between @min and @max. The @private pointer is stored
305 ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max,  in ioasid_alloc()  argument
316 	data->set = set;  in ioasid_alloc()
317 	data->private = private;  in ioasid_alloc()
318 	refcount_set(&data->refs, 1);  in ioasid_alloc()
325 	adata = active_allocator->flags & IOASID_ALLOCATOR_CUSTOM ? active_allocator->ops->pdata : data;  in ioasid_alloc()
326 	id = active_allocator->ops->alloc(min, max, adata);  in ioasid_alloc()
328 		pr_err("Failed ASID allocation %lu\n", active_allocator->flags);  in ioasid_alloc()
332 	if ((active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) &&  in ioasid_alloc()
333 	     xa_alloc(&active_allocator->xa, &id, data, XA_LIMIT(id, id), GFP_ATOMIC)) {  in ioasid_alloc()
336 		active_allocator->ops->free(id, active_allocator->ops->pdata);  in ioasid_alloc()
339 	data->id = id;  in ioasid_alloc()
351  * ioasid_get - obtain a reference to the IOASID
358 	ioasid_data = xa_load(&active_allocator->xa, ioasid);  in ioasid_get()
360 		refcount_inc(&ioasid_data->refs);  in ioasid_get()
368  * ioasid_put - Release a reference to an ioasid
382 	ioasid_data = xa_load(&active_allocator->xa, ioasid);  in ioasid_put()
388 	free = refcount_dec_and_test(&ioasid_data->refs);  in ioasid_put()
392 	active_allocator->ops->free(ioasid, active_allocator->ops->pdata);  in ioasid_put()
394 	if (active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) {  in ioasid_put()
395 		ioasid_data = xa_erase(&active_allocator->xa, ioasid);  in ioasid_put()
406  * ioasid_find - Find IOASID data
428 	ioasid_data = xa_load(&idata->xa, ioasid);  in ioasid_find()
430 		priv = ERR_PTR(-ENOENT);  in ioasid_find()
433 	if (set && ioasid_data->set != set) {  in ioasid_find()
435 		priv = ERR_PTR(-EACCES);  in ioasid_find()
439 	priv = rcu_dereference(ioasid_data->private);  in ioasid_find()
449 MODULE_AUTHOR("Jean-Philippe Brucker <jean-philippe.brucker@arm.com>");