xref: /linux/include/rdma/restrack.h (revision 1a7a05e88fa0e4e168f83585d1bb1937197a9745)
1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
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>
14 #include <linux/sched/task.h>
15 #include <uapi/rdma/rdma_netlink.h>
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,
33 	/**
34 	 * @RDMA_RESTRACK_CM_ID: Connection Manager ID (CM_ID)
35 	 */
36 	RDMA_RESTRACK_CM_ID,
37 	/**
38 	 * @RDMA_RESTRACK_MR: Memory Region (MR)
39 	 */
40 	RDMA_RESTRACK_MR,
41 	/**
42 	 * @RDMA_RESTRACK_CTX: Verbs contexts (CTX)
43 	 */
44 	RDMA_RESTRACK_CTX,
45 	/**
46 	 * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
47 	 */
48 	RDMA_RESTRACK_MAX
49 };
50 
51 #define RDMA_RESTRACK_HASH_BITS	8
52 struct ib_device;
53 struct rdma_restrack_entry;
54 
55 /**
56  * struct rdma_restrack_root - main resource tracking management
57  * entity, per-device
58  */
59 struct rdma_restrack_root {
60 	/*
61 	 * @rwsem: Read/write lock to protect lists
62 	 */
63 	struct rw_semaphore	rwsem;
64 	/**
65 	 * @hash: global database for all resources per-device
66 	 */
67 	DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
68 };
69 
70 /**
71  * struct rdma_restrack_entry - metadata per-entry
72  */
73 struct rdma_restrack_entry {
74 	/**
75 	 * @valid: validity indicator
76 	 *
77 	 * The entries are filled during rdma_restrack_add,
78 	 * can be attempted to be free during rdma_restrack_del.
79 	 *
80 	 * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
81 	 */
82 	bool			valid;
83 	/*
84 	 * @kref: Protect destroy of the resource
85 	 */
86 	struct kref		kref;
87 	/*
88 	 * @comp: Signal that all consumers of resource are completed their work
89 	 */
90 	struct completion	comp;
91 	/**
92 	 * @task: owner of resource tracking entity
93 	 *
94 	 * There are two types of entities: created by user and created
95 	 * by kernel.
96 	 *
97 	 * This is relevant for the entities created by users.
98 	 * For the entities created by kernel, this pointer will be NULL.
99 	 */
100 	struct task_struct	*task;
101 	/**
102 	 * @kern_name: name of owner for the kernel created entities.
103 	 */
104 	const char		*kern_name;
105 	/**
106 	 * @node: hash table entry
107 	 */
108 	struct hlist_node	node;
109 	/**
110 	 * @type: various objects in restrack database
111 	 */
112 	enum rdma_restrack_type	type;
113 	/**
114 	 * @user: user resource
115 	 */
116 	bool			user;
117 };
118 
119 void rdma_restrack_init(struct ib_device *dev);
120 void rdma_restrack_clean(struct ib_device *dev);
121 int rdma_restrack_count(struct ib_device *dev,
122 			enum rdma_restrack_type type,
123 			struct pid_namespace *ns);
124 
125 void rdma_restrack_kadd(struct rdma_restrack_entry *res);
126 void rdma_restrack_uadd(struct rdma_restrack_entry *res);
127 
128 /**
129  * rdma_restrack_del() - delete object from the reource tracking database
130  * @res:  resource entry
131  * @type: actual type of object to operate
132  */
133 void rdma_restrack_del(struct rdma_restrack_entry *res);
134 
135 /**
136  * rdma_is_kernel_res() - check the owner of resource
137  * @res:  resource entry
138  */
139 static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
140 {
141 	return !res->user;
142 }
143 
144 /**
145  * rdma_restrack_get() - grab to protect resource from release
146  * @res:  resource entry
147  */
148 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
149 
150 /**
151  * rdma_restrack_put() - release resource
152  * @res:  resource entry
153  */
154 int rdma_restrack_put(struct rdma_restrack_entry *res);
155 
156 /**
157  * rdma_restrack_set_task() - set the task for this resource
158  * @res:  resource entry
159  * @caller: kernel name, the current task will be used if the caller is NULL.
160  */
161 void rdma_restrack_set_task(struct rdma_restrack_entry *res,
162 			    const char *caller);
163 
164 /*
165  * Helper functions for rdma drivers when filling out
166  * nldev driver attributes.
167  */
168 int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
169 int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
170 			       u32 value);
171 int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
172 int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
173 			       u64 value);
174 #endif /* _RDMA_RESTRACK_H_ */
175