xref: /openbmc/linux/net/sunrpc/debugfs.c (revision e52a6321)
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_clnt_dir;
15 static struct dentry *rpc_xprt_dir;
16 
17 unsigned int rpc_inject_disconnect;
18 
19 static int
20 tasks_show(struct seq_file *f, void *v)
21 {
22 	u32 xid = 0;
23 	struct rpc_task *task = v;
24 	struct rpc_clnt *clnt = task->tk_client;
25 	const char *rpc_waitq = "none";
26 
27 	if (RPC_IS_QUEUED(task))
28 		rpc_waitq = rpc_qname(task->tk_waitqueue);
29 
30 	if (task->tk_rqstp)
31 		xid = be32_to_cpu(task->tk_rqstp->rq_xid);
32 
33 	seq_printf(f, "%5u %04x %6d 0x%x 0x%x %8ld %ps %sv%u %s a:%ps q:%s\n",
34 		task->tk_pid, task->tk_flags, task->tk_status,
35 		clnt->cl_clid, xid, rpc_task_timeout(task), task->tk_ops,
36 		clnt->cl_program->name, clnt->cl_vers, rpc_proc_name(task),
37 		task->tk_action, rpc_waitq);
38 	return 0;
39 }
40 
41 static void *
42 tasks_start(struct seq_file *f, loff_t *ppos)
43 	__acquires(&clnt->cl_lock)
44 {
45 	struct rpc_clnt *clnt = f->private;
46 	loff_t pos = *ppos;
47 	struct rpc_task *task;
48 
49 	spin_lock(&clnt->cl_lock);
50 	list_for_each_entry(task, &clnt->cl_tasks, tk_task)
51 		if (pos-- == 0)
52 			return task;
53 	return NULL;
54 }
55 
56 static void *
57 tasks_next(struct seq_file *f, void *v, loff_t *pos)
58 {
59 	struct rpc_clnt *clnt = f->private;
60 	struct rpc_task *task = v;
61 	struct list_head *next = task->tk_task.next;
62 
63 	++*pos;
64 
65 	/* If there's another task on list, return it */
66 	if (next == &clnt->cl_tasks)
67 		return NULL;
68 	return list_entry(next, struct rpc_task, tk_task);
69 }
70 
71 static void
72 tasks_stop(struct seq_file *f, void *v)
73 	__releases(&clnt->cl_lock)
74 {
75 	struct rpc_clnt *clnt = f->private;
76 	spin_unlock(&clnt->cl_lock);
77 }
78 
79 static const struct seq_operations tasks_seq_operations = {
80 	.start	= tasks_start,
81 	.next	= tasks_next,
82 	.stop	= tasks_stop,
83 	.show	= tasks_show,
84 };
85 
86 static int tasks_open(struct inode *inode, struct file *filp)
87 {
88 	int ret = seq_open(filp, &tasks_seq_operations);
89 	if (!ret) {
90 		struct seq_file *seq = filp->private_data;
91 		struct rpc_clnt *clnt = seq->private = inode->i_private;
92 
93 		if (!atomic_inc_not_zero(&clnt->cl_count)) {
94 			seq_release(inode, filp);
95 			ret = -EINVAL;
96 		}
97 	}
98 
99 	return ret;
100 }
101 
102 static int
103 tasks_release(struct inode *inode, struct file *filp)
104 {
105 	struct seq_file *seq = filp->private_data;
106 	struct rpc_clnt *clnt = seq->private;
107 
108 	rpc_release_client(clnt);
109 	return seq_release(inode, filp);
110 }
111 
112 static const struct file_operations tasks_fops = {
113 	.owner		= THIS_MODULE,
114 	.open		= tasks_open,
115 	.read		= seq_read,
116 	.llseek		= seq_lseek,
117 	.release	= tasks_release,
118 };
119 
120 static int do_xprt_debugfs(struct rpc_clnt *clnt, struct rpc_xprt *xprt, void *numv)
121 {
122 	int len;
123 	char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
124 	char link[9]; /* enough for 8 hex digits + NULL */
125 	int *nump = numv;
126 
127 	if (IS_ERR_OR_NULL(xprt->debugfs))
128 		return 0;
129 	len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
130 		       xprt->debugfs->d_name.name);
131 	if (len > sizeof(name))
132 		return -1;
133 	if (*nump == 0)
134 		strcpy(link, "xprt");
135 	else {
136 		len = snprintf(link, sizeof(link), "xprt%d", *nump);
137 		if (len > sizeof(link))
138 			return -1;
139 	}
140 	debugfs_create_symlink(link, clnt->cl_debugfs, name);
141 	(*nump)++;
142 	return 0;
143 }
144 
145 void
146 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
147 {
148 	int len;
149 	char name[9]; /* enough for 8 hex digits + NULL */
150 	int xprtnum = 0;
151 
152 	len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
153 	if (len >= sizeof(name))
154 		return;
155 
156 	/* make the per-client dir */
157 	clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
158 
159 	/* make tasks file */
160 	debugfs_create_file("tasks", S_IFREG | 0400, clnt->cl_debugfs, clnt,
161 			    &tasks_fops);
162 
163 	rpc_clnt_iterate_for_each_xprt(clnt, do_xprt_debugfs, &xprtnum);
164 }
165 
166 void
167 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
168 {
169 	debugfs_remove_recursive(clnt->cl_debugfs);
170 	clnt->cl_debugfs = NULL;
171 }
172 
173 static int
174 xprt_info_show(struct seq_file *f, void *v)
175 {
176 	struct rpc_xprt *xprt = f->private;
177 
178 	seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
179 	seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
180 	seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
181 	seq_printf(f, "state: 0x%lx\n", xprt->state);
182 	return 0;
183 }
184 
185 static int
186 xprt_info_open(struct inode *inode, struct file *filp)
187 {
188 	int ret;
189 	struct rpc_xprt *xprt = inode->i_private;
190 
191 	ret = single_open(filp, xprt_info_show, xprt);
192 
193 	if (!ret) {
194 		if (!xprt_get(xprt)) {
195 			single_release(inode, filp);
196 			ret = -EINVAL;
197 		}
198 	}
199 	return ret;
200 }
201 
202 static int
203 xprt_info_release(struct inode *inode, struct file *filp)
204 {
205 	struct rpc_xprt *xprt = inode->i_private;
206 
207 	xprt_put(xprt);
208 	return single_release(inode, filp);
209 }
210 
211 static const struct file_operations xprt_info_fops = {
212 	.owner		= THIS_MODULE,
213 	.open		= xprt_info_open,
214 	.read		= seq_read,
215 	.llseek		= seq_lseek,
216 	.release	= xprt_info_release,
217 };
218 
219 void
220 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
221 {
222 	int len, id;
223 	static atomic_t	cur_id;
224 	char		name[9]; /* 8 hex digits + NULL term */
225 
226 	id = (unsigned int)atomic_inc_return(&cur_id);
227 
228 	len = snprintf(name, sizeof(name), "%x", id);
229 	if (len >= sizeof(name))
230 		return;
231 
232 	/* make the per-client dir */
233 	xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
234 
235 	/* make tasks file */
236 	debugfs_create_file("info", S_IFREG | 0400, xprt->debugfs, xprt,
237 			    &xprt_info_fops);
238 
239 	atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
240 }
241 
242 void
243 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
244 {
245 	debugfs_remove_recursive(xprt->debugfs);
246 	xprt->debugfs = NULL;
247 }
248 
249 static int
250 fault_open(struct inode *inode, struct file *filp)
251 {
252 	filp->private_data = kmalloc(128, GFP_KERNEL);
253 	if (!filp->private_data)
254 		return -ENOMEM;
255 	return 0;
256 }
257 
258 static int
259 fault_release(struct inode *inode, struct file *filp)
260 {
261 	kfree(filp->private_data);
262 	return 0;
263 }
264 
265 static ssize_t
266 fault_disconnect_read(struct file *filp, char __user *user_buf,
267 		      size_t len, loff_t *offset)
268 {
269 	char *buffer = (char *)filp->private_data;
270 	size_t size;
271 
272 	size = sprintf(buffer, "%u\n", rpc_inject_disconnect);
273 	return simple_read_from_buffer(user_buf, len, offset, buffer, size);
274 }
275 
276 static ssize_t
277 fault_disconnect_write(struct file *filp, const char __user *user_buf,
278 		       size_t len, loff_t *offset)
279 {
280 	char buffer[16];
281 
282 	if (len >= sizeof(buffer))
283 		len = sizeof(buffer) - 1;
284 	if (copy_from_user(buffer, user_buf, len))
285 		return -EFAULT;
286 	buffer[len] = '\0';
287 	if (kstrtouint(buffer, 10, &rpc_inject_disconnect))
288 		return -EINVAL;
289 	return len;
290 }
291 
292 static const struct file_operations fault_disconnect_fops = {
293 	.owner		= THIS_MODULE,
294 	.open		= fault_open,
295 	.read		= fault_disconnect_read,
296 	.write		= fault_disconnect_write,
297 	.release	= fault_release,
298 };
299 
300 void __exit
301 sunrpc_debugfs_exit(void)
302 {
303 	debugfs_remove_recursive(topdir);
304 	topdir = NULL;
305 	rpc_clnt_dir = NULL;
306 	rpc_xprt_dir = NULL;
307 }
308 
309 void __init
310 sunrpc_debugfs_init(void)
311 {
312 	struct dentry *rpc_fault_dir;
313 
314 	topdir = debugfs_create_dir("sunrpc", NULL);
315 
316 	rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
317 
318 	rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
319 
320 	rpc_fault_dir = debugfs_create_dir("inject_fault", topdir);
321 
322 	debugfs_create_file("disconnect", S_IFREG | 0400, rpc_fault_dir, NULL,
323 			    &fault_disconnect_fops);
324 }
325