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
type2str(enum rdma_restrack_type type)40 static const char *type2str(enum rdma_restrack_type type)
41 {
42 static const char * const names[RDMA_RESTRACK_MAX] = {
43 [RDMA_RESTRACK_PD] = "PD",
44 [RDMA_RESTRACK_CQ] = "CQ",
45 [RDMA_RESTRACK_QP] = "QP",
46 [RDMA_RESTRACK_CM_ID] = "CM_ID",
47 [RDMA_RESTRACK_MR] = "MR",
48 [RDMA_RESTRACK_CTX] = "CTX",
49 [RDMA_RESTRACK_COUNTER] = "COUNTER",
50 };
51
52 return names[type];
53 };
54
55 /**
56 * rdma_restrack_clean() - clean resource tracking
57 * @dev: IB device
58 */
rdma_restrack_clean(struct ib_device * dev)59 void rdma_restrack_clean(struct ib_device *dev)
60 {
61 struct rdma_restrack_root *rt = dev->res;
62 struct rdma_restrack_entry *e;
63 char buf[TASK_COMM_LEN];
64 bool found = false;
65 const char *owner;
66 int i;
67
68 for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) {
69 struct xarray *xa = &dev->res[i].xa;
70
71 if (!xa_empty(xa)) {
72 unsigned long index;
73
74 if (!found) {
75 pr_err("restrack: %s", CUT_HERE);
76 dev_err(&dev->dev, "BUG: RESTRACK detected leak of resources\n");
77 }
78 xa_for_each(xa, index, e) {
79 if (rdma_is_kernel_res(e)) {
80 owner = e->kern_name;
81 } else {
82 /*
83 * There is no need to call get_task_struct here,
84 * because we can be here only if there are more
85 * get_task_struct() call than put_task_struct().
86 */
87 get_task_comm(buf, e->task);
88 owner = buf;
89 }
90
91 pr_err("restrack: %s %s object allocated by %s is not freed\n",
92 rdma_is_kernel_res(e) ? "Kernel" :
93 "User",
94 type2str(e->type), owner);
95 }
96 found = true;
97 }
98 xa_destroy(xa);
99 }
100 if (found)
101 pr_err("restrack: %s", CUT_HERE);
102
103 kfree(rt);
104 }
105
106 /**
107 * rdma_restrack_count() - the current usage of specific object
108 * @dev: IB device
109 * @type: actual type of object to operate
110 */
rdma_restrack_count(struct ib_device * dev,enum rdma_restrack_type type)111 int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type)
112 {
113 struct rdma_restrack_root *rt = &dev->res[type];
114 struct rdma_restrack_entry *e;
115 XA_STATE(xas, &rt->xa, 0);
116 u32 cnt = 0;
117
118 xa_lock(&rt->xa);
119 xas_for_each(&xas, e, U32_MAX)
120 cnt++;
121 xa_unlock(&rt->xa);
122 return cnt;
123 }
124 EXPORT_SYMBOL(rdma_restrack_count);
125
res_to_dev(struct rdma_restrack_entry * res)126 static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
127 {
128 switch (res->type) {
129 case RDMA_RESTRACK_PD:
130 return container_of(res, struct ib_pd, res)->device;
131 case RDMA_RESTRACK_CQ:
132 return container_of(res, struct ib_cq, res)->device;
133 case RDMA_RESTRACK_QP:
134 return container_of(res, struct ib_qp, res)->device;
135 case RDMA_RESTRACK_CM_ID:
136 return container_of(res, struct rdma_id_private,
137 res)->id.device;
138 case RDMA_RESTRACK_MR:
139 return container_of(res, struct ib_mr, res)->device;
140 case RDMA_RESTRACK_CTX:
141 return container_of(res, struct ib_ucontext, res)->device;
142 case RDMA_RESTRACK_COUNTER:
143 return container_of(res, struct rdma_counter, res)->device;
144 default:
145 WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
146 return NULL;
147 }
148 }
149
150 /**
151 * rdma_restrack_attach_task() - attach the task onto this resource,
152 * valid for user space restrack entries.
153 * @res: resource entry
154 * @task: the task to attach
155 */
rdma_restrack_attach_task(struct rdma_restrack_entry * res,struct task_struct * task)156 static void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
157 struct task_struct *task)
158 {
159 if (WARN_ON_ONCE(!task))
160 return;
161
162 if (res->task)
163 put_task_struct(res->task);
164 get_task_struct(task);
165 res->task = task;
166 res->user = true;
167 }
168
169 /**
170 * rdma_restrack_set_name() - set the task for this resource
171 * @res: resource entry
172 * @caller: kernel name, the current task will be used if the caller is NULL.
173 */
rdma_restrack_set_name(struct rdma_restrack_entry * res,const char * caller)174 void rdma_restrack_set_name(struct rdma_restrack_entry *res, const char *caller)
175 {
176 if (caller) {
177 res->kern_name = caller;
178 return;
179 }
180
181 rdma_restrack_attach_task(res, current);
182 }
183 EXPORT_SYMBOL(rdma_restrack_set_name);
184
185 /**
186 * rdma_restrack_parent_name() - set the restrack name properties based
187 * on parent restrack
188 * @dst: destination resource entry
189 * @parent: parent resource entry
190 */
rdma_restrack_parent_name(struct rdma_restrack_entry * dst,const struct rdma_restrack_entry * parent)191 void rdma_restrack_parent_name(struct rdma_restrack_entry *dst,
192 const struct rdma_restrack_entry *parent)
193 {
194 if (rdma_is_kernel_res(parent))
195 dst->kern_name = parent->kern_name;
196 else
197 rdma_restrack_attach_task(dst, parent->task);
198 }
199 EXPORT_SYMBOL(rdma_restrack_parent_name);
200
201 /**
202 * rdma_restrack_new() - Initializes new restrack entry to allow _put() interface
203 * to release memory in fully automatic way.
204 * @res - Entry to initialize
205 * @type - REstrack type
206 */
rdma_restrack_new(struct rdma_restrack_entry * res,enum rdma_restrack_type type)207 void rdma_restrack_new(struct rdma_restrack_entry *res,
208 enum rdma_restrack_type type)
209 {
210 kref_init(&res->kref);
211 init_completion(&res->comp);
212 res->type = type;
213 }
214 EXPORT_SYMBOL(rdma_restrack_new);
215
216 /**
217 * rdma_restrack_add() - add object to the reource tracking database
218 * @res: resource entry
219 */
rdma_restrack_add(struct rdma_restrack_entry * res)220 void rdma_restrack_add(struct rdma_restrack_entry *res)
221 {
222 struct ib_device *dev = res_to_dev(res);
223 struct rdma_restrack_root *rt;
224 int ret;
225
226 if (!dev)
227 return;
228
229 rt = &dev->res[res->type];
230
231 if (res->type == RDMA_RESTRACK_QP) {
232 /* Special case to ensure that LQPN points to right QP */
233 struct ib_qp *qp = container_of(res, struct ib_qp, res);
234
235 ret = xa_insert(&rt->xa, qp->qp_num, res, GFP_KERNEL);
236 res->id = ret ? 0 : qp->qp_num;
237 } else if (res->type == RDMA_RESTRACK_COUNTER) {
238 /* Special case to ensure that cntn points to right counter */
239 struct rdma_counter *counter;
240
241 counter = container_of(res, struct rdma_counter, res);
242 ret = xa_insert(&rt->xa, counter->id, res, GFP_KERNEL);
243 res->id = ret ? 0 : counter->id;
244 } else {
245 ret = xa_alloc_cyclic(&rt->xa, &res->id, res, xa_limit_32b,
246 &rt->next_id, GFP_KERNEL);
247 ret = (ret < 0) ? ret : 0;
248 }
249
250 if (!ret)
251 res->valid = true;
252 }
253 EXPORT_SYMBOL(rdma_restrack_add);
254
rdma_restrack_get(struct rdma_restrack_entry * res)255 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res)
256 {
257 return kref_get_unless_zero(&res->kref);
258 }
259 EXPORT_SYMBOL(rdma_restrack_get);
260
261 /**
262 * rdma_restrack_get_byid() - translate from ID to restrack object
263 * @dev: IB device
264 * @type: resource track type
265 * @id: ID to take a look
266 *
267 * Return: Pointer to restrack entry or -ENOENT in case of error.
268 */
269 struct rdma_restrack_entry *
rdma_restrack_get_byid(struct ib_device * dev,enum rdma_restrack_type type,u32 id)270 rdma_restrack_get_byid(struct ib_device *dev,
271 enum rdma_restrack_type type, u32 id)
272 {
273 struct rdma_restrack_root *rt = &dev->res[type];
274 struct rdma_restrack_entry *res;
275
276 xa_lock(&rt->xa);
277 res = xa_load(&rt->xa, id);
278 if (!res || !rdma_restrack_get(res))
279 res = ERR_PTR(-ENOENT);
280 xa_unlock(&rt->xa);
281
282 return res;
283 }
284 EXPORT_SYMBOL(rdma_restrack_get_byid);
285
restrack_release(struct kref * kref)286 static void restrack_release(struct kref *kref)
287 {
288 struct rdma_restrack_entry *res;
289
290 res = container_of(kref, struct rdma_restrack_entry, kref);
291 if (res->task) {
292 put_task_struct(res->task);
293 res->task = NULL;
294 }
295 complete(&res->comp);
296 }
297
rdma_restrack_put(struct rdma_restrack_entry * res)298 int rdma_restrack_put(struct rdma_restrack_entry *res)
299 {
300 return kref_put(&res->kref, restrack_release);
301 }
302 EXPORT_SYMBOL(rdma_restrack_put);
303
304 /**
305 * rdma_restrack_del() - delete object from the reource tracking database
306 * @res: resource entry
307 */
rdma_restrack_del(struct rdma_restrack_entry * res)308 void rdma_restrack_del(struct rdma_restrack_entry *res)
309 {
310 struct rdma_restrack_entry *old;
311 struct rdma_restrack_root *rt;
312 struct ib_device *dev;
313
314 if (!res->valid) {
315 if (res->task) {
316 put_task_struct(res->task);
317 res->task = NULL;
318 }
319 return;
320 }
321
322 dev = res_to_dev(res);
323 if (WARN_ON(!dev))
324 return;
325
326 rt = &dev->res[res->type];
327
328 old = xa_erase(&rt->xa, res->id);
329 if (res->type == RDMA_RESTRACK_MR || res->type == RDMA_RESTRACK_QP)
330 return;
331 WARN_ON(old != res);
332 res->valid = false;
333
334 rdma_restrack_put(res);
335 wait_for_completion(&res->comp);
336 }
337 EXPORT_SYMBOL(rdma_restrack_del);
338