xref: /linux/net/sunrpc/debugfs.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
1 /**
2  * debugfs interface for sunrpc
3  *
4  * (c) 2014 Jeff Layton <jlayton@primarydata.com>
5  */
6 
7 #include <linux/debugfs.h>
8 #include <linux/sunrpc/sched.h>
9 #include <linux/sunrpc/clnt.h>
10 #include "netns.h"
11 
12 static struct dentry *topdir;
13 static struct dentry *rpc_clnt_dir;
14 static struct dentry *rpc_xprt_dir;
15 
16 struct rpc_clnt_iter {
17 	struct rpc_clnt	*clnt;
18 	loff_t		pos;
19 };
20 
21 static int
22 tasks_show(struct seq_file *f, void *v)
23 {
24 	u32 xid = 0;
25 	struct rpc_task *task = v;
26 	struct rpc_clnt *clnt = task->tk_client;
27 	const char *rpc_waitq = "none";
28 
29 	if (RPC_IS_QUEUED(task))
30 		rpc_waitq = rpc_qname(task->tk_waitqueue);
31 
32 	if (task->tk_rqstp)
33 		xid = be32_to_cpu(task->tk_rqstp->rq_xid);
34 
35 	seq_printf(f, "%5u %04x %6d 0x%x 0x%x %8ld %ps %sv%u %s a:%ps q:%s\n",
36 		task->tk_pid, task->tk_flags, task->tk_status,
37 		clnt->cl_clid, xid, task->tk_timeout, task->tk_ops,
38 		clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
39 		task->tk_action, rpc_waitq);
40 	return 0;
41 }
42 
43 static void *
44 tasks_start(struct seq_file *f, loff_t *ppos)
45 	__acquires(&clnt->cl_lock)
46 {
47 	struct rpc_clnt_iter *iter = f->private;
48 	loff_t pos = *ppos;
49 	struct rpc_clnt *clnt = iter->clnt;
50 	struct rpc_task *task;
51 
52 	iter->pos = pos + 1;
53 	spin_lock(&clnt->cl_lock);
54 	list_for_each_entry(task, &clnt->cl_tasks, tk_task)
55 		if (pos-- == 0)
56 			return task;
57 	return NULL;
58 }
59 
60 static void *
61 tasks_next(struct seq_file *f, void *v, loff_t *pos)
62 {
63 	struct rpc_clnt_iter *iter = f->private;
64 	struct rpc_clnt *clnt = iter->clnt;
65 	struct rpc_task *task = v;
66 	struct list_head *next = task->tk_task.next;
67 
68 	++iter->pos;
69 	++*pos;
70 
71 	/* If there's another task on list, return it */
72 	if (next == &clnt->cl_tasks)
73 		return NULL;
74 	return list_entry(next, struct rpc_task, tk_task);
75 }
76 
77 static void
78 tasks_stop(struct seq_file *f, void *v)
79 	__releases(&clnt->cl_lock)
80 {
81 	struct rpc_clnt_iter *iter = f->private;
82 	struct rpc_clnt *clnt = iter->clnt;
83 
84 	spin_unlock(&clnt->cl_lock);
85 }
86 
87 static const struct seq_operations tasks_seq_operations = {
88 	.start	= tasks_start,
89 	.next	= tasks_next,
90 	.stop	= tasks_stop,
91 	.show	= tasks_show,
92 };
93 
94 static int tasks_open(struct inode *inode, struct file *filp)
95 {
96 	int ret = seq_open_private(filp, &tasks_seq_operations,
97 					sizeof(struct rpc_clnt_iter));
98 
99 	if (!ret) {
100 		struct seq_file *seq = filp->private_data;
101 		struct rpc_clnt_iter *iter = seq->private;
102 
103 		iter->clnt = inode->i_private;
104 
105 		if (!atomic_inc_not_zero(&iter->clnt->cl_count)) {
106 			seq_release_private(inode, filp);
107 			ret = -EINVAL;
108 		}
109 	}
110 
111 	return ret;
112 }
113 
114 static int
115 tasks_release(struct inode *inode, struct file *filp)
116 {
117 	struct seq_file *seq = filp->private_data;
118 	struct rpc_clnt_iter *iter = seq->private;
119 
120 	rpc_release_client(iter->clnt);
121 	return seq_release_private(inode, filp);
122 }
123 
124 static const struct file_operations tasks_fops = {
125 	.owner		= THIS_MODULE,
126 	.open		= tasks_open,
127 	.read		= seq_read,
128 	.llseek		= seq_lseek,
129 	.release	= tasks_release,
130 };
131 
132 int
133 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
134 {
135 	int len, err;
136 	char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
137 
138 	/* Already registered? */
139 	if (clnt->cl_debugfs)
140 		return 0;
141 
142 	len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
143 	if (len >= sizeof(name))
144 		return -EINVAL;
145 
146 	/* make the per-client dir */
147 	clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
148 	if (!clnt->cl_debugfs)
149 		return -ENOMEM;
150 
151 	/* make tasks file */
152 	err = -ENOMEM;
153 	if (!debugfs_create_file("tasks", S_IFREG | S_IRUSR, clnt->cl_debugfs,
154 				 clnt, &tasks_fops))
155 		goto out_err;
156 
157 	err = -EINVAL;
158 	rcu_read_lock();
159 	len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
160 			rcu_dereference(clnt->cl_xprt)->debugfs->d_name.name);
161 	rcu_read_unlock();
162 	if (len >= sizeof(name))
163 		goto out_err;
164 
165 	err = -ENOMEM;
166 	if (!debugfs_create_symlink("xprt", clnt->cl_debugfs, name))
167 		goto out_err;
168 
169 	return 0;
170 out_err:
171 	debugfs_remove_recursive(clnt->cl_debugfs);
172 	clnt->cl_debugfs = NULL;
173 	return err;
174 }
175 
176 void
177 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
178 {
179 	debugfs_remove_recursive(clnt->cl_debugfs);
180 	clnt->cl_debugfs = NULL;
181 }
182 
183 static int
184 xprt_info_show(struct seq_file *f, void *v)
185 {
186 	struct rpc_xprt *xprt = f->private;
187 
188 	seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
189 	seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
190 	seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
191 	seq_printf(f, "state: 0x%lx\n", xprt->state);
192 	return 0;
193 }
194 
195 static int
196 xprt_info_open(struct inode *inode, struct file *filp)
197 {
198 	int ret;
199 	struct rpc_xprt *xprt = inode->i_private;
200 
201 	ret = single_open(filp, xprt_info_show, xprt);
202 
203 	if (!ret) {
204 		if (!xprt_get(xprt)) {
205 			single_release(inode, filp);
206 			ret = -EINVAL;
207 		}
208 	}
209 	return ret;
210 }
211 
212 static int
213 xprt_info_release(struct inode *inode, struct file *filp)
214 {
215 	struct rpc_xprt *xprt = inode->i_private;
216 
217 	xprt_put(xprt);
218 	return single_release(inode, filp);
219 }
220 
221 static const struct file_operations xprt_info_fops = {
222 	.owner		= THIS_MODULE,
223 	.open		= xprt_info_open,
224 	.read		= seq_read,
225 	.llseek		= seq_lseek,
226 	.release	= xprt_info_release,
227 };
228 
229 int
230 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
231 {
232 	int len, id;
233 	static atomic_t	cur_id;
234 	char		name[9]; /* 8 hex digits + NULL term */
235 
236 	id = (unsigned int)atomic_inc_return(&cur_id);
237 
238 	len = snprintf(name, sizeof(name), "%x", id);
239 	if (len >= sizeof(name))
240 		return -EINVAL;
241 
242 	/* make the per-client dir */
243 	xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
244 	if (!xprt->debugfs)
245 		return -ENOMEM;
246 
247 	/* make tasks file */
248 	if (!debugfs_create_file("info", S_IFREG | S_IRUSR, xprt->debugfs,
249 				 xprt, &xprt_info_fops)) {
250 		debugfs_remove_recursive(xprt->debugfs);
251 		xprt->debugfs = NULL;
252 		return -ENOMEM;
253 	}
254 
255 	return 0;
256 }
257 
258 void
259 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
260 {
261 	debugfs_remove_recursive(xprt->debugfs);
262 	xprt->debugfs = NULL;
263 }
264 
265 void __exit
266 sunrpc_debugfs_exit(void)
267 {
268 	debugfs_remove_recursive(topdir);
269 }
270 
271 int __init
272 sunrpc_debugfs_init(void)
273 {
274 	topdir = debugfs_create_dir("sunrpc", NULL);
275 	if (!topdir)
276 		goto out;
277 
278 	rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
279 	if (!rpc_clnt_dir)
280 		goto out_remove;
281 
282 	rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
283 	if (!rpc_xprt_dir)
284 		goto out_remove;
285 
286 	return 0;
287 out_remove:
288 	debugfs_remove_recursive(topdir);
289 	topdir = NULL;
290 out:
291 	return -ENOMEM;
292 }
293