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 */
23int rdma_restrack_init(struct ib_device *dev)
24{
25 struct rdma_restrack_root *rt;
26 int i;
27
28 dev->res = kcalloc(n: RDMA_RESTRACK_MAX, size: 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(xa: &rt[i].xa, XA_FLAGS_ALLOC);
36
37 return 0;
38}
39
40static 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 [RDMA_RESTRACK_SRQ] = "SRQ",
51 };
52
53 return names[type];
54};
55
56/**
57 * rdma_restrack_clean() - clean resource tracking
58 * @dev: IB device
59 */
60void rdma_restrack_clean(struct ib_device *dev)
61{
62 struct rdma_restrack_root *rt = dev->res;
63 struct rdma_restrack_entry *e;
64 char buf[TASK_COMM_LEN];
65 bool found = false;
66 const char *owner;
67 int i;
68
69 for (i = 0 ; i < RDMA_RESTRACK_MAX; i++) {
70 struct xarray *xa = &dev->res[i].xa;
71
72 if (!xa_empty(xa)) {
73 unsigned long index;
74
75 if (!found) {
76 pr_err("restrack: %s", CUT_HERE);
77 dev_err(&dev->dev, "BUG: RESTRACK detected leak of resources\n");
78 }
79 xa_for_each(xa, index, e) {
80 if (rdma_is_kernel_res(res: e)) {
81 owner = e->kern_name;
82 } else {
83 /*
84 * There is no need to call get_task_struct here,
85 * because we can be here only if there are more
86 * get_task_struct() call than put_task_struct().
87 */
88 get_task_comm(buf, e->task);
89 owner = buf;
90 }
91
92 pr_err("restrack: %s %s object allocated by %s is not freed\n",
93 rdma_is_kernel_res(e) ? "Kernel" :
94 "User",
95 type2str(e->type), owner);
96 }
97 found = true;
98 }
99 xa_destroy(xa);
100 }
101 if (found)
102 pr_err("restrack: %s", CUT_HERE);
103
104 kfree(objp: rt);
105}
106
107/**
108 * rdma_restrack_count() - the current usage of specific object
109 * @dev: IB device
110 * @type: actual type of object to operate
111 */
112int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type)
113{
114 struct rdma_restrack_root *rt = &dev->res[type];
115 struct rdma_restrack_entry *e;
116 XA_STATE(xas, &rt->xa, 0);
117 u32 cnt = 0;
118
119 xa_lock(&rt->xa);
120 xas_for_each(&xas, e, U32_MAX)
121 cnt++;
122 xa_unlock(&rt->xa);
123 return cnt;
124}
125EXPORT_SYMBOL(rdma_restrack_count);
126
127static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
128{
129 switch (res->type) {
130 case RDMA_RESTRACK_PD:
131 return container_of(res, struct ib_pd, res)->device;
132 case RDMA_RESTRACK_CQ:
133 return container_of(res, struct ib_cq, res)->device;
134 case RDMA_RESTRACK_QP:
135 return container_of(res, struct ib_qp, res)->device;
136 case RDMA_RESTRACK_CM_ID:
137 return container_of(res, struct rdma_id_private,
138 res)->id.device;
139 case RDMA_RESTRACK_MR:
140 return container_of(res, struct ib_mr, res)->device;
141 case RDMA_RESTRACK_CTX:
142 return container_of(res, struct ib_ucontext, res)->device;
143 case RDMA_RESTRACK_COUNTER:
144 return container_of(res, struct rdma_counter, res)->device;
145 case RDMA_RESTRACK_SRQ:
146 return container_of(res, struct ib_srq, res)->device;
147 default:
148 WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
149 return NULL;
150 }
151}
152
153/**
154 * rdma_restrack_attach_task() - attach the task onto this resource,
155 * valid for user space restrack entries.
156 * @res: resource entry
157 * @task: the task to attach
158 */
159static void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
160 struct task_struct *task)
161{
162 if (WARN_ON_ONCE(!task))
163 return;
164
165 if (res->task)
166 put_task_struct(t: res->task);
167 get_task_struct(t: task);
168 res->task = task;
169 res->user = true;
170}
171
172/**
173 * rdma_restrack_set_name() - set the task for this resource
174 * @res: resource entry
175 * @caller: kernel name, the current task will be used if the caller is NULL.
176 */
177void rdma_restrack_set_name(struct rdma_restrack_entry *res, const char *caller)
178{
179 if (caller) {
180 res->kern_name = caller;
181 return;
182 }
183
184 rdma_restrack_attach_task(res, current);
185}
186EXPORT_SYMBOL(rdma_restrack_set_name);
187
188/**
189 * rdma_restrack_parent_name() - set the restrack name properties based
190 * on parent restrack
191 * @dst: destination resource entry
192 * @parent: parent resource entry
193 */
194void rdma_restrack_parent_name(struct rdma_restrack_entry *dst,
195 const struct rdma_restrack_entry *parent)
196{
197 if (rdma_is_kernel_res(res: parent))
198 dst->kern_name = parent->kern_name;
199 else
200 rdma_restrack_attach_task(res: dst, task: parent->task);
201}
202EXPORT_SYMBOL(rdma_restrack_parent_name);
203
204/**
205 * rdma_restrack_new() - Initializes new restrack entry to allow _put() interface
206 * to release memory in fully automatic way.
207 * @res: Entry to initialize
208 * @type: REstrack type
209 */
210void rdma_restrack_new(struct rdma_restrack_entry *res,
211 enum rdma_restrack_type type)
212{
213 kref_init(kref: &res->kref);
214 init_completion(x: &res->comp);
215 res->type = type;
216}
217EXPORT_SYMBOL(rdma_restrack_new);
218
219/**
220 * rdma_restrack_add() - add object to the reource tracking database
221 * @res: resource entry
222 */
223void rdma_restrack_add(struct rdma_restrack_entry *res)
224{
225 struct ib_device *dev = res_to_dev(res);
226 struct rdma_restrack_root *rt;
227 int ret = 0;
228
229 if (!dev)
230 return;
231
232 if (res->no_track)
233 goto out;
234
235 rt = &dev->res[res->type];
236
237 if (res->type == RDMA_RESTRACK_QP) {
238 /* Special case to ensure that LQPN points to right QP */
239 struct ib_qp *qp = container_of(res, struct ib_qp, res);
240
241 WARN_ONCE(qp->qp_num >> 24 || qp->port >> 8,
242 "QP number 0x%0X and port 0x%0X", qp->qp_num,
243 qp->port);
244 res->id = qp->qp_num;
245 if (qp->qp_type == IB_QPT_SMI || qp->qp_type == IB_QPT_GSI)
246 res->id |= qp->port << 24;
247 ret = xa_insert(xa: &rt->xa, index: res->id, entry: res, GFP_KERNEL);
248 if (ret)
249 res->id = 0;
250 } else if (res->type == RDMA_RESTRACK_COUNTER) {
251 /* Special case to ensure that cntn points to right counter */
252 struct rdma_counter *counter;
253
254 counter = container_of(res, struct rdma_counter, res);
255 ret = xa_insert(xa: &rt->xa, index: counter->id, entry: res, GFP_KERNEL);
256 res->id = ret ? 0 : counter->id;
257 } else {
258 ret = xa_alloc_cyclic(xa: &rt->xa, id: &res->id, entry: res, xa_limit_32b,
259 next: &rt->next_id, GFP_KERNEL);
260 ret = (ret < 0) ? ret : 0;
261 }
262
263out:
264 if (!ret)
265 res->valid = true;
266}
267EXPORT_SYMBOL(rdma_restrack_add);
268
269int __must_check rdma_restrack_get(struct rdma_restrack_entry *res)
270{
271 return kref_get_unless_zero(kref: &res->kref);
272}
273EXPORT_SYMBOL(rdma_restrack_get);
274
275/**
276 * rdma_restrack_get_byid() - translate from ID to restrack object
277 * @dev: IB device
278 * @type: resource track type
279 * @id: ID to take a look
280 *
281 * Return: Pointer to restrack entry or -ENOENT in case of error.
282 */
283struct rdma_restrack_entry *
284rdma_restrack_get_byid(struct ib_device *dev,
285 enum rdma_restrack_type type, u32 id)
286{
287 struct rdma_restrack_root *rt = &dev->res[type];
288 struct rdma_restrack_entry *res;
289
290 xa_lock(&rt->xa);
291 res = xa_load(&rt->xa, index: id);
292 if (!res || !rdma_restrack_get(res))
293 res = ERR_PTR(error: -ENOENT);
294 xa_unlock(&rt->xa);
295
296 return res;
297}
298EXPORT_SYMBOL(rdma_restrack_get_byid);
299
300static void restrack_release(struct kref *kref)
301{
302 struct rdma_restrack_entry *res;
303
304 res = container_of(kref, struct rdma_restrack_entry, kref);
305 if (res->task) {
306 put_task_struct(t: res->task);
307 res->task = NULL;
308 }
309 complete(&res->comp);
310}
311
312int rdma_restrack_put(struct rdma_restrack_entry *res)
313{
314 return kref_put(kref: &res->kref, release: restrack_release);
315}
316EXPORT_SYMBOL(rdma_restrack_put);
317
318/**
319 * rdma_restrack_del() - delete object from the reource tracking database
320 * @res: resource entry
321 */
322void rdma_restrack_del(struct rdma_restrack_entry *res)
323{
324 struct rdma_restrack_entry *old;
325 struct rdma_restrack_root *rt;
326 struct ib_device *dev;
327
328 if (!res->valid) {
329 if (res->task) {
330 put_task_struct(t: res->task);
331 res->task = NULL;
332 }
333 return;
334 }
335
336 if (res->no_track)
337 goto out;
338
339 dev = res_to_dev(res);
340 if (WARN_ON(!dev))
341 return;
342
343 rt = &dev->res[res->type];
344
345 old = xa_erase(&rt->xa, index: res->id);
346 WARN_ON(old != res);
347
348out:
349 res->valid = false;
350 rdma_restrack_put(res);
351 wait_for_completion(&res->comp);
352}
353EXPORT_SYMBOL(rdma_restrack_del);
354

source code of linux/drivers/infiniband/core/restrack.c