1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2 /*
3 * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
4 */
5
6 #include <rdma/rdma_cm.h>
7 #include <rdma/ib_verbs.h>
8 #include <rdma/restrack.h>
9 #include <rdma/rdma_counter.h>
10 #include <linux/mutex.h>
11 #include <linux/sched/task.h>
12 #include <linux/pid_namespace.h>
13
14 #include "cma_priv.h"
15 #include "restrack.h"
16
17 /**
18 * rdma_restrack_init() - initialize and allocate resource tracking
19 * @dev: IB device
20 *
21 * Return: 0 on success
22 */
rdma_restrack_init(struct ib_device * dev)23 int rdma_restrack_init(struct ib_device *dev)
24 {
25 struct rdma_restrack_root *rt;
26 int i;
27
28 dev->res = kcalloc(RDMA_RESTRACK_MAX, sizeof(*rt), GFP_KERNEL);
29 if (!dev->res)
30 return -ENOMEM;
31
32 rt = dev->res;
33
34 for (i = 0; i < RDMA_RESTRACK_MAX; i++)
35 xa_init_flags(&rt[i].xa, XA_FLAGS_ALLOC);
36
37 return 0;
38 }
39
40 /**
41 * rdma_restrack_clean() - clean resource tracking
42 * @dev: IB device
43 */
rdma_restrack_clean(struct ib_device * dev)44 void rdma_restrack_clean(struct ib_device *dev)
45 {
46 struct rdma_restrack_root *rt = dev->res;
47 int i;
48
49 for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) {
50 struct xarray *xa = &dev->res[i].xa;
51
52 WARN_ON(!xa_empty(xa));
53 xa_destroy(xa);
54 }
55 kfree(rt);
56 }
57
58 /**
59 * rdma_restrack_count() - the current usage of specific object
60 * @dev: IB device
61 * @type: actual type of object to operate
62 * @show_details: count driver specific objects
63 */
rdma_restrack_count(struct ib_device * dev,enum rdma_restrack_type type,bool show_details)64 int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type,
65 bool show_details)
66 {
67 struct rdma_restrack_root *rt = &dev->res[type];
68 struct rdma_restrack_entry *e;
69 XA_STATE(xas, &rt->xa, 0);
70 u32 cnt = 0;
71
72 xa_lock(&rt->xa);
73 xas_for_each(&xas, e, U32_MAX) {
74 if (xa_get_mark(&rt->xa, e->id, RESTRACK_DD) && !show_details)
75 continue;
76 cnt++;
77 }
78 xa_unlock(&rt->xa);
79 return cnt;
80 }
81 EXPORT_SYMBOL(rdma_restrack_count);
82
res_to_dev(struct rdma_restrack_entry * res)83 static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
84 {
85 switch (res->type) {
86 case RDMA_RESTRACK_PD:
87 return container_of(res, struct ib_pd, res)->device;
88 case RDMA_RESTRACK_CQ:
89 return container_of(res, struct ib_cq, res)->device;
90 case RDMA_RESTRACK_QP:
91 return container_of(res, struct ib_qp, res)->device;
92 case RDMA_RESTRACK_CM_ID:
93 return container_of(res, struct rdma_id_private,
94 res)->id.device;
95 case RDMA_RESTRACK_MR:
96 return container_of(res, struct ib_mr, res)->device;
97 case RDMA_RESTRACK_CTX:
98 return container_of(res, struct ib_ucontext, res)->device;
99 case RDMA_RESTRACK_COUNTER:
100 return container_of(res, struct rdma_counter, res)->device;
101 case RDMA_RESTRACK_SRQ:
102 return container_of(res, struct ib_srq, res)->device;
103 default:
104 WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
105 return NULL;
106 }
107 }
108
109 /**
110 * rdma_restrack_attach_task() - attach the task onto this resource,
111 * valid for user space restrack entries.
112 * @res: resource entry
113 * @task: the task to attach
114 */
rdma_restrack_attach_task(struct rdma_restrack_entry * res,struct task_struct * task)115 static void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
116 struct task_struct *task)
117 {
118 if (WARN_ON_ONCE(!task))
119 return;
120
121 if (res->task)
122 put_task_struct(res->task);
123 get_task_struct(task);
124 res->task = task;
125 res->user = true;
126 }
127
128 /**
129 * rdma_restrack_set_name() - set the task for this resource
130 * @res: resource entry
131 * @caller: kernel name, the current task will be used if the caller is NULL.
132 */
rdma_restrack_set_name(struct rdma_restrack_entry * res,const char * caller)133 void rdma_restrack_set_name(struct rdma_restrack_entry *res, const char *caller)
134 {
135 if (caller) {
136 res->kern_name = caller;
137 return;
138 }
139
140 rdma_restrack_attach_task(res, current);
141 }
142 EXPORT_SYMBOL(rdma_restrack_set_name);
143
144 /**
145 * rdma_restrack_parent_name() - set the restrack name properties based
146 * on parent restrack
147 * @dst: destination resource entry
148 * @parent: parent resource entry
149 */
rdma_restrack_parent_name(struct rdma_restrack_entry * dst,const struct rdma_restrack_entry * parent)150 void rdma_restrack_parent_name(struct rdma_restrack_entry *dst,
151 const struct rdma_restrack_entry *parent)
152 {
153 if (rdma_is_kernel_res(parent))
154 dst->kern_name = parent->kern_name;
155 else
156 rdma_restrack_attach_task(dst, parent->task);
157 }
158 EXPORT_SYMBOL(rdma_restrack_parent_name);
159
160 /**
161 * rdma_restrack_new() - Initializes new restrack entry to allow _put() interface
162 * to release memory in fully automatic way.
163 * @res: Entry to initialize
164 * @type: REstrack type
165 */
rdma_restrack_new(struct rdma_restrack_entry * res,enum rdma_restrack_type type)166 void rdma_restrack_new(struct rdma_restrack_entry *res,
167 enum rdma_restrack_type type)
168 {
169 kref_init(&res->kref);
170 init_completion(&res->comp);
171 res->type = type;
172 }
173 EXPORT_SYMBOL(rdma_restrack_new);
174
175 /**
176 * rdma_restrack_add() - add object to the reource tracking database
177 * @res: resource entry
178 */
rdma_restrack_add(struct rdma_restrack_entry * res)179 void rdma_restrack_add(struct rdma_restrack_entry *res)
180 {
181 struct ib_device *dev = res_to_dev(res);
182 struct rdma_restrack_root *rt;
183 int ret = 0;
184
185 if (!dev)
186 return;
187
188 if (res->no_track)
189 goto out;
190
191 rt = &dev->res[res->type];
192
193 if (res->type == RDMA_RESTRACK_QP) {
194 /* Special case to ensure that LQPN points to right QP */
195 struct ib_qp *qp = container_of(res, struct ib_qp, res);
196
197 WARN_ONCE(qp->qp_num >> 24 || qp->port >> 8,
198 "QP number 0x%0X and port 0x%0X", qp->qp_num,
199 qp->port);
200 res->id = qp->qp_num;
201 if (qp->qp_type == IB_QPT_SMI || qp->qp_type == IB_QPT_GSI)
202 res->id |= qp->port << 24;
203 ret = xa_insert(&rt->xa, res->id, res, GFP_KERNEL);
204 if (ret)
205 res->id = 0;
206
207 if (qp->qp_type >= IB_QPT_DRIVER)
208 xa_set_mark(&rt->xa, res->id, RESTRACK_DD);
209 } else if (res->type == RDMA_RESTRACK_COUNTER) {
210 /* Special case to ensure that cntn points to right counter */
211 struct rdma_counter *counter;
212
213 counter = container_of(res, struct rdma_counter, res);
214 ret = xa_insert(&rt->xa, counter->id, res, GFP_KERNEL);
215 res->id = ret ? 0 : counter->id;
216 } else {
217 ret = xa_alloc_cyclic(&rt->xa, &res->id, res, xa_limit_32b,
218 &rt->next_id, GFP_KERNEL);
219 ret = (ret < 0) ? ret : 0;
220 }
221
222 out:
223 if (!ret)
224 res->valid = true;
225 }
226 EXPORT_SYMBOL(rdma_restrack_add);
227
rdma_restrack_get(struct rdma_restrack_entry * res)228 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res)
229 {
230 return kref_get_unless_zero(&res->kref);
231 }
232 EXPORT_SYMBOL(rdma_restrack_get);
233
234 /**
235 * rdma_restrack_get_byid() - translate from ID to restrack object
236 * @dev: IB device
237 * @type: resource track type
238 * @id: ID to take a look
239 *
240 * Return: Pointer to restrack entry or -ENOENT in case of error.
241 */
242 struct rdma_restrack_entry *
rdma_restrack_get_byid(struct ib_device * dev,enum rdma_restrack_type type,u32 id)243 rdma_restrack_get_byid(struct ib_device *dev,
244 enum rdma_restrack_type type, u32 id)
245 {
246 struct rdma_restrack_root *rt = &dev->res[type];
247 struct rdma_restrack_entry *res;
248
249 xa_lock(&rt->xa);
250 res = xa_load(&rt->xa, id);
251 if (!res || !rdma_restrack_get(res))
252 res = ERR_PTR(-ENOENT);
253 xa_unlock(&rt->xa);
254
255 return res;
256 }
257 EXPORT_SYMBOL(rdma_restrack_get_byid);
258
restrack_release(struct kref * kref)259 static void restrack_release(struct kref *kref)
260 {
261 struct rdma_restrack_entry *res;
262
263 res = container_of(kref, struct rdma_restrack_entry, kref);
264 if (res->task) {
265 put_task_struct(res->task);
266 res->task = NULL;
267 }
268 complete(&res->comp);
269 }
270
rdma_restrack_put(struct rdma_restrack_entry * res)271 int rdma_restrack_put(struct rdma_restrack_entry *res)
272 {
273 return kref_put(&res->kref, restrack_release);
274 }
275 EXPORT_SYMBOL(rdma_restrack_put);
276
277 /**
278 * rdma_restrack_del() - delete object from the reource tracking database
279 * @res: resource entry
280 */
rdma_restrack_del(struct rdma_restrack_entry * res)281 void rdma_restrack_del(struct rdma_restrack_entry *res)
282 {
283 struct rdma_restrack_entry *old;
284 struct rdma_restrack_root *rt;
285 struct ib_device *dev;
286
287 if (!res->valid) {
288 if (res->task) {
289 put_task_struct(res->task);
290 res->task = NULL;
291 }
292 return;
293 }
294
295 if (res->no_track)
296 goto out;
297
298 dev = res_to_dev(res);
299 if (WARN_ON(!dev))
300 return;
301
302 rt = &dev->res[res->type];
303
304 old = xa_erase(&rt->xa, res->id);
305 WARN_ON(old != res);
306
307 out:
308 res->valid = false;
309 rdma_restrack_put(res);
310 wait_for_completion(&res->comp);
311 }
312 EXPORT_SYMBOL(rdma_restrack_del);
313