xref: /openbmc/linux/net/sunrpc/debugfs.c (revision e3b9f1e8)
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * debugfs interface for sunrpc
4  *
5  * (c) 2014 Jeff Layton <jlayton@primarydata.com>
6  */
7 
8 #include <linux/debugfs.h>
9 #include <linux/sunrpc/sched.h>
10 #include <linux/sunrpc/clnt.h>
11 #include "netns.h"
12 
13 static struct dentry *topdir;
14 static struct dentry *rpc_fault_dir;
15 static struct dentry *rpc_clnt_dir;
16 static struct dentry *rpc_xprt_dir;
17 
18 unsigned int rpc_inject_disconnect;
19 
20 static int
21 tasks_show(struct seq_file *f, void *v)
22 {
23 	u32 xid = 0;
24 	struct rpc_task *task = v;
25 	struct rpc_clnt *clnt = task->tk_client;
26 	const char *rpc_waitq = "none";
27 
28 	if (RPC_IS_QUEUED(task))
29 		rpc_waitq = rpc_qname(task->tk_waitqueue);
30 
31 	if (task->tk_rqstp)
32 		xid = be32_to_cpu(task->tk_rqstp->rq_xid);
33 
34 	seq_printf(f, "%5u %04x %6d 0x%x 0x%x %8ld %ps %sv%u %s a:%ps q:%s\n",
35 		task->tk_pid, task->tk_flags, task->tk_status,
36 		clnt->cl_clid, xid, task->tk_timeout, task->tk_ops,
37 		clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
38 		task->tk_action, rpc_waitq);
39 	return 0;
40 }
41 
42 static void *
43 tasks_start(struct seq_file *f, loff_t *ppos)
44 	__acquires(&clnt->cl_lock)
45 {
46 	struct rpc_clnt *clnt = f->private;
47 	loff_t pos = *ppos;
48 	struct rpc_task *task;
49 
50 	spin_lock(&clnt->cl_lock);
51 	list_for_each_entry(task, &clnt->cl_tasks, tk_task)
52 		if (pos-- == 0)
53 			return task;
54 	return NULL;
55 }
56 
57 static void *
58 tasks_next(struct seq_file *f, void *v, loff_t *pos)
59 {
60 	struct rpc_clnt *clnt = f->private;
61 	struct rpc_task *task = v;
62 	struct list_head *next = task->tk_task.next;
63 
64 	++*pos;
65 
66 	/* If there's another task on list, return it */
67 	if (next == &clnt->cl_tasks)
68 		return NULL;
69 	return list_entry(next, struct rpc_task, tk_task);
70 }
71 
72 static void
73 tasks_stop(struct seq_file *f, void *v)
74 	__releases(&clnt->cl_lock)
75 {
76 	struct rpc_clnt *clnt = f->private;
77 	spin_unlock(&clnt->cl_lock);
78 }
79 
80 static const struct seq_operations tasks_seq_operations = {
81 	.start	= tasks_start,
82 	.next	= tasks_next,
83 	.stop	= tasks_stop,
84 	.show	= tasks_show,
85 };
86 
87 static int tasks_open(struct inode *inode, struct file *filp)
88 {
89 	int ret = seq_open(filp, &tasks_seq_operations);
90 	if (!ret) {
91 		struct seq_file *seq = filp->private_data;
92 		struct rpc_clnt *clnt = seq->private = inode->i_private;
93 
94 		if (!atomic_inc_not_zero(&clnt->cl_count)) {
95 			seq_release(inode, filp);
96 			ret = -EINVAL;
97 		}
98 	}
99 
100 	return ret;
101 }
102 
103 static int
104 tasks_release(struct inode *inode, struct file *filp)
105 {
106 	struct seq_file *seq = filp->private_data;
107 	struct rpc_clnt *clnt = seq->private;
108 
109 	rpc_release_client(clnt);
110 	return seq_release(inode, filp);
111 }
112 
113 static const struct file_operations tasks_fops = {
114 	.owner		= THIS_MODULE,
115 	.open		= tasks_open,
116 	.read		= seq_read,
117 	.llseek		= seq_lseek,
118 	.release	= tasks_release,
119 };
120 
121 void
122 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
123 {
124 	int len;
125 	char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
126 	struct rpc_xprt *xprt;
127 
128 	/* Already registered? */
129 	if (clnt->cl_debugfs || !rpc_clnt_dir)
130 		return;
131 
132 	len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
133 	if (len >= sizeof(name))
134 		return;
135 
136 	/* make the per-client dir */
137 	clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
138 	if (!clnt->cl_debugfs)
139 		return;
140 
141 	/* make tasks file */
142 	if (!debugfs_create_file("tasks", S_IFREG | S_IRUSR, clnt->cl_debugfs,
143 				 clnt, &tasks_fops))
144 		goto out_err;
145 
146 	rcu_read_lock();
147 	xprt = rcu_dereference(clnt->cl_xprt);
148 	/* no "debugfs" dentry? Don't bother with the symlink. */
149 	if (!xprt->debugfs) {
150 		rcu_read_unlock();
151 		return;
152 	}
153 	len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
154 			xprt->debugfs->d_name.name);
155 	rcu_read_unlock();
156 
157 	if (len >= sizeof(name))
158 		goto out_err;
159 
160 	if (!debugfs_create_symlink("xprt", clnt->cl_debugfs, name))
161 		goto out_err;
162 
163 	return;
164 out_err:
165 	debugfs_remove_recursive(clnt->cl_debugfs);
166 	clnt->cl_debugfs = NULL;
167 }
168 
169 void
170 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
171 {
172 	debugfs_remove_recursive(clnt->cl_debugfs);
173 	clnt->cl_debugfs = NULL;
174 }
175 
176 static int
177 xprt_info_show(struct seq_file *f, void *v)
178 {
179 	struct rpc_xprt *xprt = f->private;
180 
181 	seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
182 	seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
183 	seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
184 	seq_printf(f, "state: 0x%lx\n", xprt->state);
185 	return 0;
186 }
187 
188 static int
189 xprt_info_open(struct inode *inode, struct file *filp)
190 {
191 	int ret;
192 	struct rpc_xprt *xprt = inode->i_private;
193 
194 	ret = single_open(filp, xprt_info_show, xprt);
195 
196 	if (!ret) {
197 		if (!xprt_get(xprt)) {
198 			single_release(inode, filp);
199 			ret = -EINVAL;
200 		}
201 	}
202 	return ret;
203 }
204 
205 static int
206 xprt_info_release(struct inode *inode, struct file *filp)
207 {
208 	struct rpc_xprt *xprt = inode->i_private;
209 
210 	xprt_put(xprt);
211 	return single_release(inode, filp);
212 }
213 
214 static const struct file_operations xprt_info_fops = {
215 	.owner		= THIS_MODULE,
216 	.open		= xprt_info_open,
217 	.read		= seq_read,
218 	.llseek		= seq_lseek,
219 	.release	= xprt_info_release,
220 };
221 
222 void
223 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
224 {
225 	int len, id;
226 	static atomic_t	cur_id;
227 	char		name[9]; /* 8 hex digits + NULL term */
228 
229 	if (!rpc_xprt_dir)
230 		return;
231 
232 	id = (unsigned int)atomic_inc_return(&cur_id);
233 
234 	len = snprintf(name, sizeof(name), "%x", id);
235 	if (len >= sizeof(name))
236 		return;
237 
238 	/* make the per-client dir */
239 	xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
240 	if (!xprt->debugfs)
241 		return;
242 
243 	/* make tasks file */
244 	if (!debugfs_create_file("info", S_IFREG | S_IRUSR, xprt->debugfs,
245 				 xprt, &xprt_info_fops)) {
246 		debugfs_remove_recursive(xprt->debugfs);
247 		xprt->debugfs = NULL;
248 	}
249 
250 	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
251 }
252 
253 void
254 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
255 {
256 	debugfs_remove_recursive(xprt->debugfs);
257 	xprt->debugfs = NULL;
258 }
259 
260 static int
261 fault_open(struct inode *inode, struct file *filp)
262 {
263 	filp->private_data = kmalloc(128, GFP_KERNEL);
264 	if (!filp->private_data)
265 		return -ENOMEM;
266 	return 0;
267 }
268 
269 static int
270 fault_release(struct inode *inode, struct file *filp)
271 {
272 	kfree(filp->private_data);
273 	return 0;
274 }
275 
276 static ssize_t
277 fault_disconnect_read(struct file *filp, char __user *user_buf,
278 		      size_t len, loff_t *offset)
279 {
280 	char *buffer = (char *)filp->private_data;
281 	size_t size;
282 
283 	size = sprintf(buffer, "%u\n", rpc_inject_disconnect);
284 	return simple_read_from_buffer(user_buf, len, offset, buffer, size);
285 }
286 
287 static ssize_t
288 fault_disconnect_write(struct file *filp, const char __user *user_buf,
289 		       size_t len, loff_t *offset)
290 {
291 	char buffer[16];
292 
293 	if (len >= sizeof(buffer))
294 		len = sizeof(buffer) - 1;
295 	if (copy_from_user(buffer, user_buf, len))
296 		return -EFAULT;
297 	buffer[len] = '\0';
298 	if (kstrtouint(buffer, 10, &rpc_inject_disconnect))
299 		return -EINVAL;
300 	return len;
301 }
302 
303 static const struct file_operations fault_disconnect_fops = {
304 	.owner		= THIS_MODULE,
305 	.open		= fault_open,
306 	.read		= fault_disconnect_read,
307 	.write		= fault_disconnect_write,
308 	.release	= fault_release,
309 };
310 
311 static struct dentry *
312 inject_fault_dir(struct dentry *topdir)
313 {
314 	struct dentry *faultdir;
315 
316 	faultdir = debugfs_create_dir("inject_fault", topdir);
317 	if (!faultdir)
318 		return NULL;
319 
320 	if (!debugfs_create_file("disconnect", S_IFREG | S_IRUSR, faultdir,
321 				 NULL, &fault_disconnect_fops))
322 		return NULL;
323 
324 	return faultdir;
325 }
326 
327 void __exit
328 sunrpc_debugfs_exit(void)
329 {
330 	debugfs_remove_recursive(topdir);
331 	topdir = NULL;
332 	rpc_fault_dir = NULL;
333 	rpc_clnt_dir = NULL;
334 	rpc_xprt_dir = NULL;
335 }
336 
337 void __init
338 sunrpc_debugfs_init(void)
339 {
340 	topdir = debugfs_create_dir("sunrpc", NULL);
341 	if (!topdir)
342 		return;
343 
344 	rpc_fault_dir = inject_fault_dir(topdir);
345 	if (!rpc_fault_dir)
346 		goto out_remove;
347 
348 	rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
349 	if (!rpc_clnt_dir)
350 		goto out_remove;
351 
352 	rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
353 	if (!rpc_xprt_dir)
354 		goto out_remove;
355 
356 	return;
357 out_remove:
358 	debugfs_remove_recursive(topdir);
359 	topdir = NULL;
360 	rpc_fault_dir = NULL;
361 	rpc_clnt_dir = NULL;
362 }
363