xref: /linux/net/sctp/objcnt.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /* SCTP kernel implementation
2  * (C) Copyright IBM Corp. 2001, 2004
3  *
4  * This file is part of the SCTP kernel implementation
5  *
6  * Support for memory object debugging.  This allows one to monitor the
7  * object allocations/deallocations for types instrumented for this
8  * via the proc fs.
9  *
10  * This SCTP implementation is free software;
11  * you can redistribute it and/or modify it under the terms of
12  * the GNU General Public License as published by
13  * the Free Software Foundation; either version 2, or (at your option)
14  * any later version.
15  *
16  * This SCTP implementation is distributed in the hope that it
17  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
18  *                 ************************
19  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
20  * See the GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with GNU CC; see the file COPYING.  If not, see
24  * <http://www.gnu.org/licenses/>.
25  *
26  * Please send any bug reports or fixes you make to the
27  * email address(es):
28  *    lksctp developers <linux-sctp@vger.kernel.org>
29  *
30  * Written or modified by:
31  *    Jon Grimm             <jgrimm@us.ibm.com>
32  */
33 
34 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
35 
36 #include <linux/kernel.h>
37 #include <net/sctp/sctp.h>
38 
39 /*
40  * Global counters to count raw object allocation counts.
41  * To add new counters, choose a unique suffix for the variable
42  * name as the helper macros key off this suffix to make
43  * life easier for the programmer.
44  */
45 
46 SCTP_DBG_OBJCNT(sock);
47 SCTP_DBG_OBJCNT(ep);
48 SCTP_DBG_OBJCNT(transport);
49 SCTP_DBG_OBJCNT(assoc);
50 SCTP_DBG_OBJCNT(bind_addr);
51 SCTP_DBG_OBJCNT(bind_bucket);
52 SCTP_DBG_OBJCNT(chunk);
53 SCTP_DBG_OBJCNT(addr);
54 SCTP_DBG_OBJCNT(ssnmap);
55 SCTP_DBG_OBJCNT(datamsg);
56 SCTP_DBG_OBJCNT(keys);
57 
58 /* An array to make it easy to pretty print the debug information
59  * to the proc fs.
60  */
61 static sctp_dbg_objcnt_entry_t sctp_dbg_objcnt[] = {
62 	SCTP_DBG_OBJCNT_ENTRY(sock),
63 	SCTP_DBG_OBJCNT_ENTRY(ep),
64 	SCTP_DBG_OBJCNT_ENTRY(assoc),
65 	SCTP_DBG_OBJCNT_ENTRY(transport),
66 	SCTP_DBG_OBJCNT_ENTRY(chunk),
67 	SCTP_DBG_OBJCNT_ENTRY(bind_addr),
68 	SCTP_DBG_OBJCNT_ENTRY(bind_bucket),
69 	SCTP_DBG_OBJCNT_ENTRY(addr),
70 	SCTP_DBG_OBJCNT_ENTRY(ssnmap),
71 	SCTP_DBG_OBJCNT_ENTRY(datamsg),
72 	SCTP_DBG_OBJCNT_ENTRY(keys),
73 };
74 
75 /* Callback from procfs to read out objcount information.
76  * Walk through the entries in the sctp_dbg_objcnt array, dumping
77  * the raw object counts for each monitored type.
78  */
79 static int sctp_objcnt_seq_show(struct seq_file *seq, void *v)
80 {
81 	int i;
82 
83 	i = (int)*(loff_t *)v;
84 	seq_setwidth(seq, 127);
85 	seq_printf(seq, "%s: %d", sctp_dbg_objcnt[i].label,
86 				atomic_read(sctp_dbg_objcnt[i].counter));
87 	seq_pad(seq, '\n');
88 	return 0;
89 }
90 
91 static void *sctp_objcnt_seq_start(struct seq_file *seq, loff_t *pos)
92 {
93 	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
94 }
95 
96 static void sctp_objcnt_seq_stop(struct seq_file *seq, void *v)
97 {
98 }
99 
100 static void *sctp_objcnt_seq_next(struct seq_file *seq, void *v, loff_t *pos)
101 {
102 	++*pos;
103 	return (*pos >= ARRAY_SIZE(sctp_dbg_objcnt)) ? NULL : (void *)pos;
104 }
105 
106 static const struct seq_operations sctp_objcnt_seq_ops = {
107 	.start = sctp_objcnt_seq_start,
108 	.next  = sctp_objcnt_seq_next,
109 	.stop  = sctp_objcnt_seq_stop,
110 	.show  = sctp_objcnt_seq_show,
111 };
112 
113 static int sctp_objcnt_seq_open(struct inode *inode, struct file *file)
114 {
115 	return seq_open(file, &sctp_objcnt_seq_ops);
116 }
117 
118 static const struct file_operations sctp_objcnt_ops = {
119 	.open	 = sctp_objcnt_seq_open,
120 	.read	 = seq_read,
121 	.llseek	 = seq_lseek,
122 	.release = seq_release,
123 };
124 
125 /* Initialize the objcount in the proc filesystem.  */
126 void sctp_dbg_objcnt_init(struct net *net)
127 {
128 	struct proc_dir_entry *ent;
129 
130 	ent = proc_create("sctp_dbg_objcnt", 0,
131 			  net->sctp.proc_net_sctp, &sctp_objcnt_ops);
132 	if (!ent)
133 		pr_warn("sctp_dbg_objcnt: Unable to create /proc entry.\n");
134 }
135 
136 /* Cleanup the objcount entry in the proc filesystem.  */
137 void sctp_dbg_objcnt_exit(struct net *net)
138 {
139 	remove_proc_entry("sctp_dbg_objcnt", net->sctp.proc_net_sctp);
140 }
141 
142 
143