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_MAX: Last entry, used for array dclarations
43 */
44 RDMA_RESTRACK_MAX
45 };
46
47 #define RDMA_RESTRACK_HASH_BITS 8
48 struct rdma_restrack_entry;
49
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);
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);
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 */
rdma_is_kernel_res(struct rdma_restrack_entry * res)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 /**
168 * rdma_restrack_put() - release resource
169 * @res: resource entry
170 */
171 int rdma_restrack_put(struct rdma_restrack_entry *res);
172
173 /**
174 * rdma_restrack_set_task() - set the task for this resource
175 * @res: resource entry
176 * @task: task struct
177 */
rdma_restrack_set_task(struct rdma_restrack_entry * res,struct task_struct * task)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
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);
197 #endif /* _RDMA_RESTRACK_H_ */
198
