xref: /openbmc/linux/include/rdma/restrack.h (revision 5b4cb650)
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 rdma_restrack_entry;
53 
54 /**
55  * struct rdma_restrack_root - main resource tracking management
56  * entity, per-device
57  */
58 struct rdma_restrack_root {
59 	/*
60 	 * @rwsem: Read/write lock to protect lists
61 	 */
62 	struct rw_semaphore	rwsem;
63 	/**
64 	 * @hash: global database for all resources per-device
65 	 */
66 	DECLARE_HASHTABLE(hash, RDMA_RESTRACK_HASH_BITS);
67 	/**
68 	 * @fill_res_entry: driver-specific fill function
69 	 *
70 	 * Allows rdma drivers to add their own restrack attributes.
71 	 */
72 	int (*fill_res_entry)(struct sk_buff *msg,
73 			      struct rdma_restrack_entry *entry);
74 };
75 
76 /**
77  * struct rdma_restrack_entry - metadata per-entry
78  */
79 struct rdma_restrack_entry {
80 	/**
81 	 * @valid: validity indicator
82 	 *
83 	 * The entries are filled during rdma_restrack_add,
84 	 * can be attempted to be free during rdma_restrack_del.
85 	 *
86 	 * As an example for that, see mlx5 QPs with type MLX5_IB_QPT_HW_GSI
87 	 */
88 	bool			valid;
89 	/*
90 	 * @kref: Protect destroy of the resource
91 	 */
92 	struct kref		kref;
93 	/*
94 	 * @comp: Signal that all consumers of resource are completed their work
95 	 */
96 	struct completion	comp;
97 	/**
98 	 * @task: owner of resource tracking entity
99 	 *
100 	 * There are two types of entities: created by user and created
101 	 * by kernel.
102 	 *
103 	 * This is relevant for the entities created by users.
104 	 * For the entities created by kernel, this pointer will be NULL.
105 	 */
106 	struct task_struct	*task;
107 	/**
108 	 * @kern_name: name of owner for the kernel created entities.
109 	 */
110 	const char		*kern_name;
111 	/**
112 	 * @node: hash table entry
113 	 */
114 	struct hlist_node	node;
115 	/**
116 	 * @type: various objects in restrack database
117 	 */
118 	enum rdma_restrack_type	type;
119 	/**
120 	 * @user: user resource
121 	 */
122 	bool			user;
123 };
124 
125 /**
126  * rdma_restrack_init() - initialize resource tracking
127  * @res:  resource tracking root
128  */
129 void rdma_restrack_init(struct rdma_restrack_root *res);
130 
131 /**
132  * rdma_restrack_clean() - clean resource tracking
133  * @res:  resource tracking root
134  */
135 void rdma_restrack_clean(struct rdma_restrack_root *res);
136 
137 /**
138  * rdma_restrack_count() - the current usage of specific object
139  * @res:  resource entry
140  * @type: actual type of object to operate
141  * @ns:   PID namespace
142  */
143 int rdma_restrack_count(struct rdma_restrack_root *res,
144 			enum rdma_restrack_type type,
145 			struct pid_namespace *ns);
146 
147 void rdma_restrack_kadd(struct rdma_restrack_entry *res);
148 void rdma_restrack_uadd(struct rdma_restrack_entry *res);
149 
150 /**
151  * rdma_restrack_del() - delete object from the reource tracking database
152  * @res:  resource entry
153  * @type: actual type of object to operate
154  */
155 void rdma_restrack_del(struct rdma_restrack_entry *res);
156 
157 /**
158  * rdma_is_kernel_res() - check the owner of resource
159  * @res:  resource entry
160  */
161 static inline bool rdma_is_kernel_res(struct rdma_restrack_entry *res)
162 {
163 	return !res->user;
164 }
165 
166 /**
167  * rdma_restrack_get() - grab to protect resource from release
168  * @res:  resource entry
169  */
170 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res);
171 
172 /**
173  * rdma_restrack_put() - release resource
174  * @res:  resource entry
175  */
176 int rdma_restrack_put(struct rdma_restrack_entry *res);
177 
178 /**
179  * rdma_restrack_set_task() - set the task for this resource
180  * @res:  resource entry
181  * @caller: kernel name, the current task will be used if the caller is NULL.
182  */
183 void rdma_restrack_set_task(struct rdma_restrack_entry *res,
184 			    const char *caller);
185 
186 /*
187  * Helper functions for rdma drivers when filling out
188  * nldev driver attributes.
189  */
190 int rdma_nl_put_driver_u32(struct sk_buff *msg, const char *name, u32 value);
191 int rdma_nl_put_driver_u32_hex(struct sk_buff *msg, const char *name,
192 			       u32 value);
193 int rdma_nl_put_driver_u64(struct sk_buff *msg, const char *name, u64 value);
194 int rdma_nl_put_driver_u64_hex(struct sk_buff *msg, const char *name,
195 			       u64 value);
196 #endif /* _RDMA_RESTRACK_H_ */
197