[linux-2.6-block.git] / include / rdma / restrack.h

/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
 * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
 */

#ifndef _RDMA_RESTRACK_H_
#define _RDMA_RESTRACK_H_

#include <linux/typecheck.h>
#include <linux/rwsem.h>
#include <linux/sched.h>
#include <linux/kref.h>
#include <linux/completion.h>
#include <linux/sched/task.h>
#include <uapi/rdma/rdma_netlink.h>

/**
 * enum rdma_restrack_type - HW objects to track
 */
enum rdma_restrack_type {
	/**
	 * @RDMA_RESTRACK_PD: Protection domain (PD)
	 */
	RDMA_RESTRACK_PD,
	/**
	 * @RDMA_RESTRACK_CQ: Completion queue (CQ)
	 */
	RDMA_RESTRACK_CQ,
	/**
	 * @RDMA_RESTRACK_QP: Queue pair (QP)
	 */
	RDMA_RESTRACK_QP,
	/**
	 * @RDMA_RESTRACK_CM_ID: Connection Manager ID (CM_ID)
	 */
	RDMA_RESTRACK_CM_ID,
	/**
	 * @RDMA_RESTRACK_MR: Memory Region (MR)
	 */
	RDMA_RESTRACK_MR,
	/**
	 * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
	 */
	RDMA_RESTRACK_MAX
};

#define RDMA_RESTRACK_HASH_BITS	8
struct rdma_restrack_entry;

/**
 * struct rdma_restrack_root - main resource tracking management
 * entity, per-device
 */
struct rdma_restrack_root {
	/*
	 * @rwsem: Read/write lock to protect lists
	 */
	struct rw_semaphore	rwsem;
	/**
	 * @hash: global database for all resources per-device
	 */
	DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
	/**
	 * @fill_res_entry: driver-specific fill function
	 *
	 * Allows rdma drivers to add their own restrack attributes.
	 */
	int (*fill_res_entry)(struct sk_buff *msg,
			      struct rdma_restrack_entry *entry);
};

/**
 * struct rdma_restrack_entry - metadata per-entry
 */
struct rdma_restrack_entry {
	/**
	 * @valid: validity indicator
	 *
	 * The entries are filled during rdma_restrack_add,
	 * can be attempted to be free during rdma_restrack_del.
	 *
	 * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
	 */
	bool			valid;
	/*
	 * @kref: Protect destroy of the resource
	 */
	struct kref		kref;
	/*
	 * @comp: Signal that all consumers of resource are completed their work
	 */
	struct completion	comp;
	/**
	 * @task: owner of resource tracking entity
	 *
	 * There are two types of entities: created by user and created
	 * by kernel.
	 *
	 * This is relevant for the entities created by users.
	 * For the entities created by kernel, this pointer will be NULL.
	 */
	struct task_struct	*task;
	/**
	 * @kern_name: name of owner for the kernel created entities.
	 */
	const char		*kern_name;
	/**
	 * @node: hash table entry
	 */
	struct hlist_node	node;
	/**
	 * @type: various objects in restrack database
	 */
	enum rdma_restrack_type	type;
};

/**
 * rdma_restrack_init() - initialize resource tracking
 * @res:  resource tracking root
 */
void rdma_restrack_init(struct rdma_restrack_root *res);

/**
 * rdma_restrack_clean() - clean resource tracking
 * @res:  resource tracking root
 */
void rdma_restrack_clean(struct rdma_restrack_root *res);

/**
 * rdma_restrack_count() - the current usage of specific object
 * @res:  resource entry
 * @type: actual type of object to operate
 * @ns:   PID namespace
 */
int rdma_restrack_count(struct rdma_restrack_root *res,
			enum rdma_restrack_type type,
			struct pid_namespace *ns);

/**
 * rdma_restrack_add() - add object to the reource tracking database
 * @res:  resource entry
 */
void rdma_restrack_add(struct rdma_restrack_entry *res);

/**
 * rdma_restrack_del() - delete object from the reource tracking database
 * @res:  resource entry
 * @type: actual type of object to operate
 */
void rdma_restrack_del(struct rdma_restrack_entry *res);

/**
 * rdma_is_kernel_res() - check the owner of resource
 * @res:  resource entry
 */
static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
{
	return !res->task;
}

/**
 * rdma_restrack_get() - grab to protect resource from release
 * @res:  resource entry
 */
int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);

/**
 * rdma_restrack_put() - release resource
 * @res:  resource entry
 */
int rdma_restrack_put(struct rdma_restrack_entry *res);

/**
 * rdma_restrack_set_task() - set the task for this resource
 * @res:  resource entry
 * @task: task struct
 */
static inline void rdma_restrack_set_task(struct rdma_restrack_entry *res,
					  struct task_struct *task)
{
	if (res->task)
		put_task_struct(res->task);
	get_task_struct(task);
	res->task = task;
}

/*
 * Helper functions for rdma drivers when filling out
 * nldev driver attributes.
 */
int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
			       u32 value);
int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
			       u64 value);
#endif /* _RDMA_RESTRACK_H_ */
Commit	Line	Data
33edc3b2	1	/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
02d8883f LR	2	/*
	3	* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
	4	*/
	5
	6	#ifndef _RDMA_RESTRACK_H_
	7	#define _RDMA_RESTRACK_H_
	8
	9	#include <linux/typecheck.h>
	10	#include <linux/rwsem.h>
	11	#include <linux/sched.h>
	12	#include <linux/kref.h>
	13	#include <linux/completion.h>
00313983	14	#include <linux/sched/task.h>
73937e8a	15	#include <uapi/rdma/rdma_netlink.h>
02d8883f LR	16
	17	/**
	18	* enum rdma_restrack_type - HW objects to track
	19	*/
	20	enum rdma_restrack_type {
	21	/**
	22	* @RDMA_RESTRACK_PD: Protection domain (PD)
	23	*/
	24	RDMA_RESTRACK_PD,
	25	/**
	26	* @RDMA_RESTRACK_CQ: Completion queue (CQ)
	27	*/
	28	RDMA_RESTRACK_CQ,
	29	/**
	30	* @RDMA_RESTRACK_QP: Queue pair (QP)
	31	*/
	32	RDMA_RESTRACK_QP,
00313983 SW	33	/**
	34	* @RDMA_RESTRACK_CM_ID: Connection Manager ID (CM_ID)
	35	*/
	36	RDMA_RESTRACK_CM_ID,
fccec5b8 SW	37	/**
	38	* @RDMA_RESTRACK_MR: Memory Region (MR)
	39	*/
	40	RDMA_RESTRACK_MR,
02d8883f LR	41	/**
	42	* @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
	43	*/
	44	RDMA_RESTRACK_MAX
	45	};
	46
	47	#define RDMA_RESTRACK_HASH_BITS 8
da5c8507 SW	48	struct rdma_restrack_entry;
da5c8507 SW	49
02d8883f LR	50	/**
	51	* struct rdma_restrack_root - main resource tracking management
	52	* entity, per-device
	53	*/
	54	struct rdma_restrack_root {
	55	/*
	56	* @rwsem: Read/write lock to protect lists
	57	*/
	58	struct rw_semaphore rwsem;
	59	/**
	60	* @hash: global database for all resources per-device
	61	*/
	62	DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
da5c8507 SW	63	/**
	64	* @fill_res_entry: driver-specific fill function
	65	*
	66	* Allows rdma drivers to add their own restrack attributes.
	67	*/
	68	int (fill_res_entry)(struct sk_buff msg,
	69	struct rdma_restrack_entry *entry);
02d8883f LR	70	};
	71
	72	/**
	73	* struct rdma_restrack_entry - metadata per-entry
	74	*/
	75	struct rdma_restrack_entry {
	76	/**
	77	* @valid: validity indicator
	78	*
	79	* The entries are filled during rdma_restrack_add,
	80	* can be attempted to be free during rdma_restrack_del.
	81	*
	82	* As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
	83	*/
	84	bool valid;
	85	/*
	86	* @kref: Protect destroy of the resource
	87	*/
	88	struct kref kref;
	89	/*
	90	* @comp: Signal that all consumers of resource are completed their work
	91	*/
	92	struct completion comp;
	93	/**
	94	* @task: owner of resource tracking entity
	95	*
	96	* There are two types of entities: created by user and created
	97	* by kernel.
	98	*
	99	* This is relevant for the entities created by users.
	100	* For the entities created by kernel, this pointer will be NULL.
	101	*/
	102	struct task_struct *task;
	103	/**
	104	* @kern_name: name of owner for the kernel created entities.
	105	*/
	106	const char *kern_name;
	107	/**
	108	* @node: hash table entry
	109	*/
	110	struct hlist_node node;
	111	/**
	112	* @type: various objects in restrack database
	113	*/
	114	enum rdma_restrack_type type;
	115	};
	116
	117	/**
	118	* rdma_restrack_init() - initialize resource tracking
	119	* @res: resource tracking root
	120	*/
	121	void rdma_restrack_init(struct rdma_restrack_root *res);
	122
	123	/**
	124	* rdma_restrack_clean() - clean resource tracking
	125	* @res: resource tracking root
	126	*/
	127	void rdma_restrack_clean(struct rdma_restrack_root *res);
	128
	129	/**
	130	* rdma_restrack_count() - the current usage of specific object
	131	* @res: resource entry
	132	* @type: actual type of object to operate
	133	* @ns: PID namespace
134	*/
135	int rdma_restrack_count(struct rdma_restrack_root *res,
136	enum rdma_restrack_type type,
137	struct pid_namespace *ns);
138
139	/**
140	* rdma_restrack_add() - add object to the reource tracking database
141	* @res: resource entry
142	*/
143	void rdma_restrack_add(struct rdma_restrack_entry *res);
144
145	/**
146	* rdma_restrack_del() - delete object from the reource tracking database
147	* @res: resource entry
148	* @type: actual type of object to operate
149	*/
150	void rdma_restrack_del(struct rdma_restrack_entry *res);
151
152	/**
153	* rdma_is_kernel_res() - check the owner of resource
154	* @res: resource entry
155	*/
156	static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
157	{
158	return !res->task;
159	}
160
161	/**
162	* rdma_restrack_get() - grab to protect resource from release
163	* @res: resource entry
164	*/
165	int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
166
167	/**
03286030	168	* rdma_restrack_put() - release resource
02d8883f LR	169	* @res: resource entry
	170	*/
	171	int rdma_restrack_put(struct rdma_restrack_entry *res);
00313983 SW	172
	173	/**
	174	* rdma_restrack_set_task() - set the task for this resource
	175	* @res: resource entry
	176	* @task: task struct
	177	*/
	178	static inline void rdma_restrack_set_task(struct rdma_restrack_entry *res,
	179	struct task_struct *task)
	180	{
	181	if (res->task)
	182	put_task_struct(res->task);
	183	get_task_struct(task);
	184	res->task = task;
	185	}
	186
73937e8a SW	187	/*
	188	* Helper functions for rdma drivers when filling out
	189	* nldev driver attributes.
	190	*/
	191	int rdma_nl_put_driver_u32(struct sk_buff msg, const char name, u32 value);
	192	int rdma_nl_put_driver_u32_hex(struct sk_buff msg, const char name,
	193	u32 value);
	194	int rdma_nl_put_driver_u64(struct sk_buff msg, const char name, u64 value);
	195	int rdma_nl_put_driver_u64_hex(struct sk_buff msg, const char name,
	196	u64 value);
02d8883f	197	#endif /* _RDMA_RESTRACK_H_ */