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_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, rpc_task_timeout(task), 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 static int do_xprt_debugfs(struct rpc_clnt *clnt, struct rpc_xprt *xprt, void *numv)
 122 {
 123         int len;
 124         char name[24]; /* enough for "../../rpc_xprt/ + 8 hex digits + NULL */
 125         char link[9]; /* enough for 8 hex digits + NULL */
 126         int *nump = numv;
 127
 128         if (IS_ERR_OR_NULL(xprt->debugfs))
 129                 return 0;
 130         len = snprintf(name, sizeof(name), "../../rpc_xprt/%s",
 131                        xprt->debugfs->d_name.name);
 132         if (len > sizeof(name))
 133                 return -1;
 134         if (*nump == 0)
 135                 strcpy(link, "xprt");
 136         else {
 137                 len = snprintf(link, sizeof(link), "xprt%d", *nump);
 138                 if (len > sizeof(link))
 139                         return -1;
 140         }
 141         if (!debugfs_create_symlink(link, clnt->cl_debugfs, name))
 142                 return -1;
 143         (*nump)++;
 144         return 0;
 145 }
 146
 147 void
 148 rpc_clnt_debugfs_register(struct rpc_clnt *clnt)
 149 {
 150         int len;
 151         char name[9]; /* enough for 8 hex digits + NULL */
 152         int xprtnum = 0;
 153
 154         /* Already registered? */
 155         if (clnt->cl_debugfs || !rpc_clnt_dir)
 156                 return;
 157
 158         len = snprintf(name, sizeof(name), "%x", clnt->cl_clid);
 159         if (len >= sizeof(name))
 160                 return;
 161
 162         /* make the per-client dir */
 163         clnt->cl_debugfs = debugfs_create_dir(name, rpc_clnt_dir);
 164         if (!clnt->cl_debugfs)
 165                 return;
 166
 167         /* make tasks file */
 168         if (!debugfs_create_file("tasks", S_IFREG | 0400, clnt->cl_debugfs,
 169                                  clnt, &tasks_fops))
 170                 goto out_err;
 171
 172         if (rpc_clnt_iterate_for_each_xprt(clnt, do_xprt_debugfs, &xprtnum) < 0)
 173                 goto out_err;
 174
 175         return;
 176 out_err:
 177         debugfs_remove_recursive(clnt->cl_debugfs);
 178         clnt->cl_debugfs = NULL;
 179 }
 180
 181 void
 182 rpc_clnt_debugfs_unregister(struct rpc_clnt *clnt)
 183 {
 184         debugfs_remove_recursive(clnt->cl_debugfs);
 185         clnt->cl_debugfs = NULL;
 186 }
 187
 188 static int
 189 xprt_info_show(struct seq_file *f, void *v)
 190 {
 191         struct rpc_xprt *xprt = f->private;
 192
 193         seq_printf(f, "netid: %s\n", xprt->address_strings[RPC_DISPLAY_NETID]);
 194         seq_printf(f, "addr:  %s\n", xprt->address_strings[RPC_DISPLAY_ADDR]);
 195         seq_printf(f, "port:  %s\n", xprt->address_strings[RPC_DISPLAY_PORT]);
 196         seq_printf(f, "state: 0x%lx\n", xprt->state);
 197         return 0;
 198 }
 199
 200 static int
 201 xprt_info_open(struct inode *inode, struct file *filp)
 202 {
 203         int ret;
 204         struct rpc_xprt *xprt = inode->i_private;
 205
 206         ret = single_open(filp, xprt_info_show, xprt);
 207
 208         if (!ret) {
 209                 if (!xprt_get(xprt)) {
 210                         single_release(inode, filp);
 211                         ret = -EINVAL;
 212                 }
 213         }
 214         return ret;
 215 }
 216
 217 static int
 218 xprt_info_release(struct inode *inode, struct file *filp)
 219 {
 220         struct rpc_xprt *xprt = inode->i_private;
 221
 222         xprt_put(xprt);
 223         return single_release(inode, filp);
 224 }
 225
 226 static const struct file_operations xprt_info_fops = {
 227         .owner          = THIS_MODULE,
 228         .open           = xprt_info_open,
 229         .read           = seq_read,
 230         .llseek         = seq_lseek,
 231         .release        = xprt_info_release,
 232 };
 233
 234 void
 235 rpc_xprt_debugfs_register(struct rpc_xprt *xprt)
 236 {
 237         int len, id;
 238         static atomic_t cur_id;
 239         char            name[9]; /* 8 hex digits + NULL term */
 240
 241         if (!rpc_xprt_dir)
 242                 return;
 243
 244         id = (unsigned int)atomic_inc_return(&cur_id);
 245
 246         len = snprintf(name, sizeof(name), "%x", id);
 247         if (len >= sizeof(name))
 248                 return;
 249
 250         /* make the per-client dir */
 251         xprt->debugfs = debugfs_create_dir(name, rpc_xprt_dir);
 252         if (!xprt->debugfs)
 253                 return;
 254
 255         /* make tasks file */
 256         if (!debugfs_create_file("info", S_IFREG | 0400, xprt->debugfs,
 257                                  xprt, &xprt_info_fops)) {
 258                 debugfs_remove_recursive(xprt->debugfs);
 259                 xprt->debugfs = NULL;
 260         }
 261
 262         atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect);
 263 }
 264
 265 void
 266 rpc_xprt_debugfs_unregister(struct rpc_xprt *xprt)
 267 {
 268         debugfs_remove_recursive(xprt->debugfs);
 269         xprt->debugfs = NULL;
 270 }
 271
 272 static int
 273 fault_open(struct inode *inode, struct file *filp)
 274 {
 275         filp->private_data = kmalloc(128, GFP_KERNEL);
 276         if (!filp->private_data)
 277                 return -ENOMEM;
 278         return 0;
 279 }
 280
 281 static int
 282 fault_release(struct inode *inode, struct file *filp)
 283 {
 284         kfree(filp->private_data);
 285         return 0;
 286 }
 287
 288 static ssize_t
 289 fault_disconnect_read(struct file *filp, char __user *user_buf,
 290                       size_t len, loff_t *offset)
 291 {
 292         char *buffer = (char *)filp->private_data;
 293         size_t size;
 294
 295         size = sprintf(buffer, "%u\n", rpc_inject_disconnect);
 296         return simple_read_from_buffer(user_buf, len, offset, buffer, size);
 297 }
 298
 299 static ssize_t
 300 fault_disconnect_write(struct file *filp, const char __user *user_buf,
 301                        size_t len, loff_t *offset)
 302 {
 303         char buffer[16];
 304
 305         if (len >= sizeof(buffer))
 306                 len = sizeof(buffer) - 1;
 307         if (copy_from_user(buffer, user_buf, len))
 308                 return -EFAULT;
 309         buffer[len] = '\0';
 310         if (kstrtouint(buffer, 10, &rpc_inject_disconnect))
 311                 return -EINVAL;
 312         return len;
 313 }
 314
 315 static const struct file_operations fault_disconnect_fops = {
 316         .owner          = THIS_MODULE,
 317         .open           = fault_open,
 318         .read           = fault_disconnect_read,
 319         .write          = fault_disconnect_write,
 320         .release        = fault_release,
 321 };
 322
 323 static struct dentry *
 324 inject_fault_dir(struct dentry *topdir)
 325 {
 326         struct dentry *faultdir;
 327
 328         faultdir = debugfs_create_dir("inject_fault", topdir);
 329         if (!faultdir)
 330                 return NULL;
 331
 332         if (!debugfs_create_file("disconnect", S_IFREG | 0400, faultdir,
 333                                  NULL, &fault_disconnect_fops))
 334                 return NULL;
 335
 336         return faultdir;
 337 }
 338
 339 void __exit
 340 sunrpc_debugfs_exit(void)
 341 {
 342         debugfs_remove_recursive(topdir);
 343         topdir = NULL;
 344         rpc_fault_dir = NULL;
 345         rpc_clnt_dir = NULL;
 346         rpc_xprt_dir = NULL;
 347 }
 348
 349 void __init
 350 sunrpc_debugfs_init(void)
 351 {
 352         topdir = debugfs_create_dir("sunrpc", NULL);
 353         if (!topdir)
 354                 return;
 355
 356         rpc_fault_dir = inject_fault_dir(topdir);
 357         if (!rpc_fault_dir)
 358                 goto out_remove;
 359
 360         rpc_clnt_dir = debugfs_create_dir("rpc_clnt", topdir);
 361         if (!rpc_clnt_dir)
 362                 goto out_remove;
 363
 364         rpc_xprt_dir = debugfs_create_dir("rpc_xprt", topdir);
 365         if (!rpc_xprt_dir)
 366                 goto out_remove;
 367
 368         return;
 369 out_remove:
 370         debugfs_remove_recursive(topdir);
 371         topdir = NULL;
 372         rpc_fault_dir = NULL;
 373         rpc_clnt_dir = NULL;
 374 }