1 // SPDX-License-Identifier: GPL-2.0
21  * struct ioasid_allocator_data - Internal data structure to hold information
24  * - Default allocator always has its own XArray to track the IOASIDs allocated.
25  * - Custom allocators may share allocation helpers with different private data.
26  *   Custom allocators that share the same helper functions also share the same
33  * 3. When all custom allocators sharing the same helper functions are
37  *    functions, outstanding IOASIDs are preserved.
41  * @ops:	allocator helper functions and its data
61 static ioasid_t default_alloc(ioasid_t min, ioasid_t max, void *opaque);
77 static ioasid_t default_alloc(ioasid_t min, ioasid_t max, void *opaque)  in default_alloc()  argument
81 	if (xa_alloc(&default_allocator.xa, &id, opaque, XA_LIMIT(min, max), GFP_ATOMIC)) {  in default_alloc()
82 		pr_err("Failed to alloc ioasid from %d to %d\n", min, max);  in default_alloc()
97 /* Allocate and initialize a new custom allocator with its helper functions */
106 	xa_init_flags(&ia_data->xa, XA_FLAGS_ALLOC);  in ioasid_alloc_allocator()
107 	INIT_LIST_HEAD(&ia_data->slist);  in ioasid_alloc_allocator()
108 	ia_data->flags |= IOASID_ALLOCATOR_CUSTOM;  in ioasid_alloc_allocator()
109 	ia_data->ops = ops;  in ioasid_alloc_allocator()
112 	list_add_tail(&ops->list, &ia_data->slist);  in ioasid_alloc_allocator()
119 	return (a->free == b->free) && (a->alloc == b->alloc);  in use_same_ops()
123  * ioasid_register_allocator - register a custom allocator
148 		ret = -ENOMEM;  in ioasid_register_allocator()
160 		if (xa_empty(&active_allocator->xa)) {  in ioasid_register_allocator()
162 			list_add_tail(&ia_data->list, &allocators_list);  in ioasid_register_allocator()
166 		ret = -EAGAIN;  in ioasid_register_allocator()
172 		if (pallocator->ops == ops) {  in ioasid_register_allocator()
174 			ret = -EEXIST;  in ioasid_register_allocator()
176 		} else if (use_same_ops(pallocator->ops, ops)) {  in ioasid_register_allocator()
182 			list_add_tail(&ops->list, &pallocator->slist);  in ioasid_register_allocator()
186 	list_add_tail(&ia_data->list, &allocators_list);  in ioasid_register_allocator()
199  * ioasid_unregister_allocator - Remove a custom IOASID allocator ops
218 		if (!use_same_ops(pallocator->ops, ops))  in ioasid_unregister_allocator()
221 		if (list_is_singular(&pallocator->slist)) {  in ioasid_unregister_allocator()
222 			/* No shared helper functions */  in ioasid_unregister_allocator()
223 			list_del(&pallocator->list);  in ioasid_unregister_allocator()
229 			WARN_ON(!xa_empty(&pallocator->xa));  in ioasid_unregister_allocator()
246 		list_for_each_entry(sops, &pallocator->slist, list) {  in ioasid_unregister_allocator()
248 				list_del(&ops->list);  in ioasid_unregister_allocator()
261  * ioasid_set_data - Set private data for an allocated ioasid
274 	ioasid_data = xa_load(&active_allocator->xa, ioasid);  in ioasid_set_data()
276 		rcu_assign_pointer(ioasid_data->private, data);  in ioasid_set_data()
278 		ret = -ENOENT;  in ioasid_set_data()
293  * ioasid_alloc - Allocate an IOASID
296  * @max: the maximum ID (inclusive)
299  * Allocate an ID between @min and @max. The @private pointer is stored
304 ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max,  in ioasid_alloc()  argument
315 	data->set = set;  in ioasid_alloc()
316 	data->private = private;  in ioasid_alloc()
323 	adata = active_allocator->flags & IOASID_ALLOCATOR_CUSTOM ? active_allocator->ops->pdata : data;  in ioasid_alloc()
324 	id = active_allocator->ops->alloc(min, max, adata);  in ioasid_alloc()
326 		pr_err("Failed ASID allocation %lu\n", active_allocator->flags);  in ioasid_alloc()
330 	if ((active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) &&  in ioasid_alloc()
331 	     xa_alloc(&active_allocator->xa, &id, data, XA_LIMIT(id, id), GFP_ATOMIC)) {  in ioasid_alloc()
334 		active_allocator->ops->free(id, active_allocator->ops->pdata);  in ioasid_alloc()
337 	data->id = id;  in ioasid_alloc()
349  * ioasid_free - Free an ioasid
357 	ioasid_data = xa_load(&active_allocator->xa, ioasid);  in ioasid_free()
363 	active_allocator->ops->free(ioasid, active_allocator->ops->pdata);  in ioasid_free()
365 	if (active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) {  in ioasid_free()
366 		ioasid_data = xa_erase(&active_allocator->xa, ioasid);  in ioasid_free()
376  * ioasid_find - Find IOASID data
398 	ioasid_data = xa_load(&idata->xa, ioasid);  in ioasid_find()
400 		priv = ERR_PTR(-ENOENT);  in ioasid_find()
403 	if (set && ioasid_data->set != set) {  in ioasid_find()
405 		priv = ERR_PTR(-EACCES);  in ioasid_find()
409 	priv = rcu_dereference(ioasid_data->private);  in ioasid_find()
419 MODULE_AUTHOR("Jean-Philippe Brucker <jean-philippe.brucker@arm.com>");