[mirror_ubuntu-jammy-kernel.git] / include / rdma / uverbs_types.h

/*
 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#ifndef _UVERBS_TYPES_
#define _UVERBS_TYPES_

#include <linux/kernel.h>
#include <rdma/ib_verbs.h>

struct uverbs_obj_type;

struct uverbs_obj_type_class {
	/*
	 * Get an ib_uobject that corresponds to the given id from ucontext,
	 * These functions could create or destroy objects if required.
	 * The action will be finalized only when commit, abort or put fops are
	 * called.
	 * The flow of the different actions is:
	 * [alloc]:	 Starts with alloc_begin. The handlers logic is than
	 *		 executed. If the handler is successful, alloc_commit
	 *		 is called and the object is inserted to the repository.
	 *		 Once alloc_commit completes the object is visible to
	 *		 other threads and userspace.
	 e		 Otherwise, alloc_abort is called and the object is
	 *		 destroyed.
	 * [lookup]:	 Starts with lookup_get which fetches and locks the
	 *		 object. After the handler finished using the object, it
	 *		 needs to call lookup_put to unlock it. The write flag
	 *		 indicates if the object is locked for exclusive access.
	 * [remove]:	 Starts with lookup_get with write flag set. This locks
	 *		 the object for exclusive access. If the handler code
	 *		 completed successfully, remove_commit is called and
	 *		 the ib_uobject is removed from the context's uobjects
	 *		 repository and put. The object itself is destroyed as
	 *		 well. Once remove succeeds new krefs to the object
	 *		 cannot be acquired by other threads or userspace and
	 *		 the hardware driver is removed from the object.
	 *		 Other krefs on the object may still exist.
	 *		 If the handler code failed, lookup_put should be
	 *		 called. This callback is used when the context
	 *		 is destroyed as well (process termination,
	 *		 reset flow).
	 */
	struct ib_uobject *(*alloc_begin)(const struct uverbs_obj_type *type,
					  struct ib_ucontext *ucontext);
	void (*alloc_commit)(struct ib_uobject *uobj);
	void (*alloc_abort)(struct ib_uobject *uobj);

	struct ib_uobject *(*lookup_get)(const struct uverbs_obj_type *type,
					 struct ib_ucontext *ucontext, int id,
					 bool write);
	void (*lookup_put)(struct ib_uobject *uobj, bool write);
	/*
	 * Must be called with the write lock held. If successful uobj is
	 * invalid on return. On failure uobject is left completely
	 * unchanged
	 */
	int __must_check (*remove_commit)(struct ib_uobject *uobj,
					  enum rdma_remove_reason why);
	u8    needs_kfree_rcu;
};

struct uverbs_obj_type {
	const struct uverbs_obj_type_class * const type_class;
	size_t	     obj_size;
	unsigned int destroy_order;
};

/*
 * Objects type classes which support a detach state (object is still alive but
 * it's not attached to any context need to make sure:
 * (a) no call through to a driver after a detach is called
 * (b) detach isn't called concurrently with context_cleanup
 */

struct uverbs_obj_idr_type {
	/*
	 * In idr based objects, uverbs_obj_type_class points to a generic
	 * idr operations. In order to specialize the underlying types (e.g. CQ,
	 * QPs, etc.), we add destroy_object specific callbacks.
	 */
	struct uverbs_obj_type  type;

	/* Free driver resources from the uobject, make the driver uncallable,
	 * and move the uobject to the detached state. If the object was
	 * destroyed by the user's request, a failure should leave the uobject
	 * completely unchanged.
	 */
	int __must_check (*destroy_object)(struct ib_uobject *uobj,
					   enum rdma_remove_reason why);
};

struct ib_uobject *rdma_lookup_get_uobject(const struct uverbs_obj_type *type,
					   struct ib_ucontext *ucontext,
					   int id, bool write);
void rdma_lookup_put_uobject(struct ib_uobject *uobj, bool write);
struct ib_uobject *rdma_alloc_begin_uobject(const struct uverbs_obj_type *type,
					    struct ib_ucontext *ucontext);
void rdma_alloc_abort_uobject(struct ib_uobject *uobj);
int __must_check rdma_remove_commit_uobject(struct ib_uobject *uobj);
int rdma_alloc_commit_uobject(struct ib_uobject *uobj);

extern const struct uverbs_obj_type_class uverbs_idr_class;

#define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) -	\
				   sizeof(char))
#define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _order)				\
	{								\
		.destroy_order = _order,				\
		.type_class = &uverbs_idr_class,			\
		.obj_size = (_size) +					\
			  UVERBS_BUILD_BUG_ON((_size) <			\
					      sizeof(struct ib_uobject)), \
	}
#define UVERBS_TYPE_ALLOC_IDR(_order)					\
	 UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), _order)
#endif
Commit	Line	Data
38321256 MB	1	/*
	2	* Copyright (c) 2017, Mellanox Technologies inc. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the
	8	* OpenIB.org BSD license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or
	11	* without modification, are permitted provided that the following
	12	* conditions are met:
	13	*
	14	* - Redistributions of source code must retain the above
	15	* copyright notice, this list of conditions and the following
	16	* disclaimer.
	17	*
	18	* - Redistributions in binary form must reproduce the above
	19	* copyright notice, this list of conditions and the following
	20	* disclaimer in the documentation and/or other materials
	21	* provided with the distribution.
	22	*
	23	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	24	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	25	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	26	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	27	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	28	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	29	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	30	* SOFTWARE.
	31	*/
	32
	33	#ifndef _UVERBS_TYPES_
	34	#define _UVERBS_TYPES_
	35
	36	#include <linux/kernel.h>
	37	#include <rdma/ib_verbs.h>
	38
	39	struct uverbs_obj_type;
	40
	41	struct uverbs_obj_type_class {
	42	/*
	43	* Get an ib_uobject that corresponds to the given id from ucontext,
	44	* These functions could create or destroy objects if required.
	45	* The action will be finalized only when commit, abort or put fops are
	46	* called.
	47	* The flow of the different actions is:
	48	* [alloc]: Starts with alloc_begin. The handlers logic is than
	49	* executed. If the handler is successful, alloc_commit
	50	* is called and the object is inserted to the repository.
	51	* Once alloc_commit completes the object is visible to
	52	* other threads and userspace.
	53	e Otherwise, alloc_abort is called and the object is
	54	* destroyed.
	55	* [lookup]: Starts with lookup_get which fetches and locks the
	56	* object. After the handler finished using the object, it
	57	* needs to call lookup_put to unlock it. The write flag
	58	* indicates if the object is locked for exclusive access.
	59	* [remove]: Starts with lookup_get with write flag set. This locks
	60	* the object for exclusive access. If the handler code
	61	* completed successfully, remove_commit is called and
	62	* the ib_uobject is removed from the context's uobjects
	63	* repository and put. The object itself is destroyed as
	64	* well. Once remove succeeds new krefs to the object
65	* cannot be acquired by other threads or userspace and
66	* the hardware driver is removed from the object.
67	* Other krefs on the object may still exist.
68	* If the handler code failed, lookup_put should be
69	* called. This callback is used when the context
70	* is destroyed as well (process termination,
71	* reset flow).
72	*/
73	struct ib_uobject (alloc_begin)(const struct uverbs_obj_type *type,
74	struct ib_ucontext *ucontext);
75	void (alloc_commit)(struct ib_uobject uobj);
76	void (alloc_abort)(struct ib_uobject uobj);
77
78	struct ib_uobject (lookup_get)(const struct uverbs_obj_type *type,
79	struct ib_ucontext *ucontext, int id,
80	bool write);
81	void (lookup_put)(struct ib_uobject uobj, bool write);
82	/*
83	* Must be called with the write lock held. If successful uobj is
84	* invalid on return. On failure uobject is left completely
85	* unchanged
86	*/
87	int __must_check (remove_commit)(struct ib_uobject uobj,
88	enum rdma_remove_reason why);
89	u8 needs_kfree_rcu;
90	};
91
92	struct uverbs_obj_type {
93	const struct uverbs_obj_type_class * const type_class;
94	size_t obj_size;
95	unsigned int destroy_order;
96	};
97
98	/*
99	* Objects type classes which support a detach state (object is still alive but
100	* it's not attached to any context need to make sure:
101	* (a) no call through to a driver after a detach is called
102	* (b) detach isn't called concurrently with context_cleanup
103	*/
104
105	struct uverbs_obj_idr_type {
106	/*
107	* In idr based objects, uverbs_obj_type_class points to a generic
108	* idr operations. In order to specialize the underlying types (e.g. CQ,
109	* QPs, etc.), we add destroy_object specific callbacks.
110	*/
111	struct uverbs_obj_type type;
112
113	/* Free driver resources from the uobject, make the driver uncallable,
114	* and move the uobject to the detached state. If the object was
115	* destroyed by the user's request, a failure should leave the uobject
116	* completely unchanged.
117	*/
118	int __must_check (destroy_object)(struct ib_uobject uobj,
119	enum rdma_remove_reason why);
120	};
121
122	struct ib_uobject rdma_lookup_get_uobject(const struct uverbs_obj_type type,
123	struct ib_ucontext *ucontext,
124	int id, bool write);
125	void rdma_lookup_put_uobject(struct ib_uobject *uobj, bool write);
126	struct ib_uobject rdma_alloc_begin_uobject(const struct uverbs_obj_type type,
127	struct ib_ucontext *ucontext);
128	void rdma_alloc_abort_uobject(struct ib_uobject *uobj);
129	int __must_check rdma_remove_commit_uobject(struct ib_uobject *uobj);
130	int rdma_alloc_commit_uobject(struct ib_uobject *uobj);
131
6be60aed MB	132	extern const struct uverbs_obj_type_class uverbs_idr_class;
	133
	134	#define UVERBS_BUILD_BUG_ON(cond) (sizeof(char[1 - 2 * !!(cond)]) - \
	135	sizeof(char))
	136	#define UVERBS_TYPE_ALLOC_IDR_SZ(_size, _order) \
	137	{ \
	138	.destroy_order = _order, \
	139	.type_class = &uverbs_idr_class, \
	140	.obj_size = (_size) + \
	141	UVERBS_BUILD_BUG_ON((_size) < \
	142	sizeof(struct ib_uobject)), \
	143	}
	144	#define UVERBS_TYPE_ALLOC_IDR(_order) \
	145	UVERBS_TYPE_ALLOC_IDR_SZ(sizeof(struct ib_uobject), _order)
38321256	146	#endif