Merge tag 'nfs-for-5.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
[sfrench/cifs-2.6.git] / net / sunrpc / debugfs.c
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 }