aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/core/restrack.c
blob: 035af568ba64fa89011bd7f76ec567bbca22e563 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
/*
 * Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved.
 */

#include <rdma/rdma_cm.h>
#include <rdma/ib_verbs.h>
#include <rdma/restrack.h>
#include <linux/mutex.h>
#include <linux/sched/task.h>
#include <linux/pid_namespace.h>

#include "cma_priv.h"

static int fill_res_noop(struct sk_buff *msg,
			 struct rdma_restrack_entry *entry)
{
	return 0;
}

void rdma_restrack_init(struct rdma_restrack_root *res)
{
	init_rwsem(&res->rwsem);
	res->fill_res_entry = fill_res_noop;
}

static const char *type2str(enum rdma_restrack_type type)
{
	static const char * const names[RDMA_RESTRACK_MAX] = {
		[RDMA_RESTRACK_PD] = "PD",
		[RDMA_RESTRACK_CQ] = "CQ",
		[RDMA_RESTRACK_QP] = "QP",
		[RDMA_RESTRACK_CM_ID] = "CM_ID",
		[RDMA_RESTRACK_MR] = "MR",
	};

	return names[type];
};

void rdma_restrack_clean(struct rdma_restrack_root *res)
{
	struct rdma_restrack_entry *e;
	char buf[TASK_COMM_LEN];
	struct ib_device *dev;
	const char *owner;
	int bkt;

	if (hash_empty(res->hash))
		return;

	dev = container_of(res, struct ib_device, res);
	pr_err("restrack: %s", CUT_HERE);
	dev_err(&dev->dev, "BUG: RESTRACK detected leak of resources\n");
	hash_for_each(res->hash, bkt, e, node) {
		if (rdma_is_kernel_res(e)) {
			owner = e->kern_name;
		} else {
			/*
			 * There is no need to call get_task_struct here,
			 * because we can be here only if there are more
			 * get_task_struct() call than put_task_struct().
			 */
			get_task_comm(buf, e->task);
			owner = buf;
		}

		pr_err("restrack: %s %s object allocated by %s is not freed\n",
		       rdma_is_kernel_res(e) ? "Kernel" : "User",
		       type2str(e->type), owner);
	}
	pr_err("restrack: %s", CUT_HERE);
}

int rdma_restrack_count(struct rdma_restrack_root *res,
			enum rdma_restrack_type type,
			struct pid_namespace *ns)
{
	struct rdma_restrack_entry *e;
	u32 cnt = 0;

	down_read(&res->rwsem);
	hash_for_each_possible(res->hash, e, node, type) {
		if (ns == &init_pid_ns ||
		    (!rdma_is_kernel_res(e) &&
		     ns == task_active_pid_ns(e->task)))
			cnt++;
	}
	up_read(&res->rwsem);
	return cnt;
}
EXPORT_SYMBOL(rdma_restrack_count);

static void set_kern_name(struct rdma_restrack_entry *res)
{
	struct ib_pd *pd;

	switch (res->type) {
	case RDMA_RESTRACK_QP:
		pd = container_of(res, struct ib_qp, res)->pd;
		if (!pd) {
			WARN_ONCE(true, "XRC QPs are not supported\n");
			/* Survive, despite the programmer's error */
			res->kern_name = " ";
		}
		break;
	case RDMA_RESTRACK_MR:
		pd = container_of(res, struct ib_mr, res)->pd;
		break;
	default:
		/* Other types set kern_name directly */
		pd = NULL;
		break;
	}

	if (pd)
		res->kern_name = pd->res.kern_name;
}

static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
{
	switch (res->type) {
	case RDMA_RESTRACK_PD:
		return container_of(res, struct ib_pd, res)->device;
	case RDMA_RESTRACK_CQ:
		return container_of(res, struct ib_cq, res)->device;
	case RDMA_RESTRACK_QP:
		return container_of(res, struct ib_qp, res)->device;
	case RDMA_RESTRACK_CM_ID:
		return container_of(res, struct rdma_id_private,
				    res)->id.device;
	case RDMA_RESTRACK_MR:
		return container_of(res, struct ib_mr, res)->device;
	default:
		WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
		return NULL;
	}
}

static bool res_is_user(struct rdma_restrack_entry *res)
{
	switch (res->type) {
	case RDMA_RESTRACK_PD:
		return container_of(res, struct ib_pd, res)->uobject;
	case RDMA_RESTRACK_CQ:
		return container_of(res, struct ib_cq, res)->uobject;
	case RDMA_RESTRACK_QP:
		return container_of(res, struct ib_qp, res)->uobject;
	case RDMA_RESTRACK_CM_ID:
		return !res->kern_name;
	case RDMA_RESTRACK_MR:
		return container_of(res, struct ib_mr, res)->pd->uobject;
	default:
		WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
		return false;
	}
}

void rdma_restrack_set_task(struct rdma_restrack_entry *res,
			    const char *caller)
{
	if (caller) {
		res->kern_name = caller;
		return;
	}

	if (res->task)
		put_task_struct(res->task);
	get_task_struct(current);
	res->task = current;
}
EXPORT_SYMBOL(rdma_restrack_set_task);

void rdma_restrack_add(struct rdma_restrack_entry *res)
{
	struct ib_device *dev = res_to_dev(res);

	if (!dev)
		return;

	if (res->type != RDMA_RESTRACK_CM_ID || !res_is_user(res))
		res->task = NULL;

	if (res_is_user(res)) {
		if (!res->task)
			rdma_restrack_set_task(res, NULL);
		res->kern_name = NULL;
	} else {
		set_kern_name(res);
	}

	kref_init(&res->kref);
	init_completion(&res->comp);
	res->valid = true;

	down_write(&dev->res.rwsem);
	hash_add(dev->res.hash, &res->node, res->type);
	up_write(&dev->res.rwsem);
}
EXPORT_SYMBOL(rdma_restrack_add);

int __must_check rdma_restrack_get(struct rdma_restrack_entry *res)
{
	return kref_get_unless_zero(&res->kref);
}
EXPORT_SYMBOL(rdma_restrack_get);

static void restrack_release(struct kref *kref)
{
	struct rdma_restrack_entry *res;

	res = container_of(kref, struct rdma_restrack_entry, kref);
	complete(&res->comp);
}

int rdma_restrack_put(struct rdma_restrack_entry *res)
{
	return kref_put(&res->kref, restrack_release);
}
EXPORT_SYMBOL(rdma_restrack_put);

void rdma_restrack_del(struct rdma_restrack_entry *res)
{
	struct ib_device *dev;

	if (!res->valid)
		return;

	dev = res_to_dev(res);
	if (!dev)
		return;

	rdma_restrack_put(res);

	wait_for_completion(&res->comp);

	down_write(&dev->res.rwsem);
	hash_del(&res->node);
	res->valid = false;
	if (res->task)
		put_task_struct(res->task);
	up_write(&dev->res.rwsem);
}
EXPORT_SYMBOL(rdma_restrack_del);