1 /* /proc interface for AFS
2 *
3 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/proc_fs.h>
15 #include <linux/seq_file.h>
16 #include <linux/sched.h>
17 #include <asm/uaccess.h>
18 #include "internal.h"
19
20 static struct proc_dir_entry *proc_afs;
21
22
23 static int afs_proc_cells_open(struct inode *inode, struct file *file);
24 static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
25 static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
26 static void afs_proc_cells_stop(struct seq_file *p, void *v);
27 static int afs_proc_cells_show(struct seq_file *m, void *v);
28 static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
29 size_t size, loff_t *_pos);
30
31 static const struct seq_operations afs_proc_cells_ops = {
32 .start = afs_proc_cells_start,
33 .next = afs_proc_cells_next,
34 .stop = afs_proc_cells_stop,
35 .show = afs_proc_cells_show,
36 };
37
38 static const struct file_operations afs_proc_cells_fops = {
39 .open = afs_proc_cells_open,
40 .read = seq_read,
41 .write = afs_proc_cells_write,
42 .llseek = seq_lseek,
43 .release = seq_release,
44 .owner = THIS_MODULE,
45 };
46
47 static int afs_proc_rootcell_open(struct inode *inode, struct file *file);
48 static int afs_proc_rootcell_release(struct inode *inode, struct file *file);
49 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
50 size_t size, loff_t *_pos);
51 static ssize_t afs_proc_rootcell_write(struct file *file,
52 const char __user *buf,
53 size_t size, loff_t *_pos);
54
55 static const struct file_operations afs_proc_rootcell_fops = {
56 .open = afs_proc_rootcell_open,
57 .read = afs_proc_rootcell_read,
58 .write = afs_proc_rootcell_write,
59 .llseek = no_llseek,
60 .release = afs_proc_rootcell_release,
61 .owner = THIS_MODULE,
62 };
63
64 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
65 static int afs_proc_cell_volumes_release(struct inode *inode,
66 struct file *file);
67 static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
68 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
69 loff_t *pos);
70 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
71 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
72
73 static const struct seq_operations afs_proc_cell_volumes_ops = {
74 .start = afs_proc_cell_volumes_start,
75 .next = afs_proc_cell_volumes_next,
76 .stop = afs_proc_cell_volumes_stop,
77 .show = afs_proc_cell_volumes_show,
78 };
79
80 static const struct file_operations afs_proc_cell_volumes_fops = {
81 .open = afs_proc_cell_volumes_open,
82 .read = seq_read,
83 .llseek = seq_lseek,
84 .release = afs_proc_cell_volumes_release,
85 .owner = THIS_MODULE,
86 };
87
88 static int afs_proc_cell_vlservers_open(struct inode *inode,
89 struct file *file);
90 static int afs_proc_cell_vlservers_release(struct inode *inode,
91 struct file *file);
92 static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
93 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
94 loff_t *pos);
95 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
96 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
97
98 static const struct seq_operations afs_proc_cell_vlservers_ops = {
99 .start = afs_proc_cell_vlservers_start,
100 .next = afs_proc_cell_vlservers_next,
101 .stop = afs_proc_cell_vlservers_stop,
102 .show = afs_proc_cell_vlservers_show,
103 };
104
105 static const struct file_operations afs_proc_cell_vlservers_fops = {
106 .open = afs_proc_cell_vlservers_open,
107 .read = seq_read,
108 .llseek = seq_lseek,
109 .release = afs_proc_cell_vlservers_release,
110 .owner = THIS_MODULE,
111 };
112
113 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
114 static int afs_proc_cell_servers_release(struct inode *inode,
115 struct file *file);
116 static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
117 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
118 loff_t *pos);
119 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
120 static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
121
122 static const struct seq_operations afs_proc_cell_servers_ops = {
123 .start = afs_proc_cell_servers_start,
124 .next = afs_proc_cell_servers_next,
125 .stop = afs_proc_cell_servers_stop,
126 .show = afs_proc_cell_servers_show,
127 };
128
129 static const struct file_operations afs_proc_cell_servers_fops = {
130 .open = afs_proc_cell_servers_open,
131 .read = seq_read,
132 .llseek = seq_lseek,
133 .release = afs_proc_cell_servers_release,
134 .owner = THIS_MODULE,
135 };
136
137 /*
138 * initialise the /proc/fs/afs/ directory
139 */
afs_proc_init(void)140 int afs_proc_init(void)
141 {
142 struct proc_dir_entry *p;
143
144 _enter("");
145
146 proc_afs = proc_mkdir("fs/afs", NULL);
147 if (!proc_afs)
148 goto error_dir;
149
150 p = proc_create("cells", 0, proc_afs, &afs_proc_cells_fops);
151 if (!p)
152 goto error_cells;
153
154 p = proc_create("rootcell", 0, proc_afs, &afs_proc_rootcell_fops);
155 if (!p)
156 goto error_rootcell;
157
158 _leave(" = 0");
159 return 0;
160
161 error_rootcell:
162 remove_proc_entry("cells", proc_afs);
163 error_cells:
164 remove_proc_entry("fs/afs", NULL);
165 error_dir:
166 _leave(" = -ENOMEM");
167 return -ENOMEM;
168 }
169
170 /*
171 * clean up the /proc/fs/afs/ directory
172 */
afs_proc_cleanup(void)173 void afs_proc_cleanup(void)
174 {
175 remove_proc_entry("rootcell", proc_afs);
176 remove_proc_entry("cells", proc_afs);
177 remove_proc_entry("fs/afs", NULL);
178 }
179
180 /*
181 * open "/proc/fs/afs/cells" which provides a summary of extant cells
182 */
afs_proc_cells_open(struct inode * inode,struct file * file)183 static int afs_proc_cells_open(struct inode *inode, struct file *file)
184 {
185 struct seq_file *m;
186 int ret;
187
188 ret = seq_open(file, &afs_proc_cells_ops);
189 if (ret < 0)
190 return ret;
191
192 m = file->private_data;
193 m->private = PDE(inode)->data;
194
195 return 0;
196 }
197
198 /*
199 * set up the iterator to start reading from the cells list and return the
200 * first item
201 */
afs_proc_cells_start(struct seq_file * m,loff_t * _pos)202 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
203 {
204 /* lock the list against modification */
205 down_read(&afs_proc_cells_sem);
206 return seq_list_start_head(&afs_proc_cells, *_pos);
207 }
208
209 /*
210 * move to next cell in cells list
211 */
afs_proc_cells_next(struct seq_file * p,void * v,loff_t * pos)212 static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
213 {
214 return seq_list_next(v, &afs_proc_cells, pos);
215 }
216
217 /*
218 * clean up after reading from the cells list
219 */
afs_proc_cells_stop(struct seq_file * p,void * v)220 static void afs_proc_cells_stop(struct seq_file *p, void *v)
221 {
222 up_read(&afs_proc_cells_sem);
223 }
224
225 /*
226 * display a header line followed by a load of cell lines
227 */
afs_proc_cells_show(struct seq_file * m,void * v)228 static int afs_proc_cells_show(struct seq_file *m, void *v)
229 {
230 struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
231
232 if (v == &afs_proc_cells) {
233 /* display header on line 1 */
234 seq_puts(m, "USE NAME\n");
235 return 0;
236 }
237
238 /* display one cell per line on subsequent lines */
239 seq_printf(m, "%3d %s\n",
240 atomic_read(&cell->usage), cell->name);
241 return 0;
242 }
243
244 /*
245 * handle writes to /proc/fs/afs/cells
246 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
247 */
afs_proc_cells_write(struct file * file,const char __user * buf,size_t size,loff_t * _pos)248 static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
249 size_t size, loff_t *_pos)
250 {
251 char *kbuf, *name, *args;
252 int ret;
253
254 /* start by dragging the command into memory */
255 if (size <= 1 || size >= PAGE_SIZE)
256 return -EINVAL;
257
258 kbuf = kmalloc(size + 1, GFP_KERNEL);
259 if (!kbuf)
260 return -ENOMEM;
261
262 ret = -EFAULT;
263 if (copy_from_user(kbuf, buf, size) != 0)
264 goto done;
265 kbuf[size] = 0;
266
267 /* trim to first NL */
268 name = memchr(kbuf, '\n', size);
269 if (name)
270 *name = 0;
271
272 /* split into command, name and argslist */
273 name = strchr(kbuf, ' ');
274 if (!name)
275 goto inval;
276 do {
277 *name++ = 0;
278 } while(*name == ' ');
279 if (!*name)
280 goto inval;
281
282 args = strchr(name, ' ');
283 if (!args)
284 goto inval;
285 do {
286 *args++ = 0;
287 } while(*args == ' ');
288 if (!*args)
289 goto inval;
290
291 /* determine command to perform */
292 _debug("cmd=%s name=%s args=%s", kbuf, name, args);
293
294 if (strcmp(kbuf, "add") == 0) {
295 struct afs_cell *cell;
296
297 cell = afs_cell_create(name, strlen(name), args, false);
298 if (IS_ERR(cell)) {
299 ret = PTR_ERR(cell);
300 goto done;
301 }
302
303 afs_put_cell(cell);
304 printk("kAFS: Added new cell '%s'\n", name);
305 } else {
306 goto inval;
307 }
308
309 ret = size;
310
311 done:
312 kfree(kbuf);
313 _leave(" = %d", ret);
314 return ret;
315
316 inval:
317 ret = -EINVAL;
318 printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
319 goto done;
320 }
321
322 /*
323 * Stubs for /proc/fs/afs/rootcell
324 */
afs_proc_rootcell_open(struct inode * inode,struct file * file)325 static int afs_proc_rootcell_open(struct inode *inode, struct file *file)
326 {
327 return 0;
328 }
329
afs_proc_rootcell_release(struct inode * inode,struct file * file)330 static int afs_proc_rootcell_release(struct inode *inode, struct file *file)
331 {
332 return 0;
333 }
334
afs_proc_rootcell_read(struct file * file,char __user * buf,size_t size,loff_t * _pos)335 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
336 size_t size, loff_t *_pos)
337 {
338 return 0;
339 }
340
341 /*
342 * handle writes to /proc/fs/afs/rootcell
343 * - to initialize rootcell: echo "cell.name:192.168.231.14"
344 */
afs_proc_rootcell_write(struct file * file,const char __user * buf,size_t size,loff_t * _pos)345 static ssize_t afs_proc_rootcell_write(struct file *file,
346 const char __user *buf,
347 size_t size, loff_t *_pos)
348 {
349 char *kbuf, *s;
350 int ret;
351
352 /* start by dragging the command into memory */
353 if (size <= 1 || size >= PAGE_SIZE)
354 return -EINVAL;
355
356 ret = -ENOMEM;
357 kbuf = kmalloc(size + 1, GFP_KERNEL);
358 if (!kbuf)
359 goto nomem;
360
361 ret = -EFAULT;
362 if (copy_from_user(kbuf, buf, size) != 0)
363 goto infault;
364 kbuf[size] = 0;
365
366 /* trim to first NL */
367 s = memchr(kbuf, '\n', size);
368 if (s)
369 *s = 0;
370
371 /* determine command to perform */
372 _debug("rootcell=%s", kbuf);
373
374 ret = afs_cell_init(kbuf);
375 if (ret >= 0)
376 ret = size; /* consume everything, always */
377
378 infault:
379 kfree(kbuf);
380 nomem:
381 _leave(" = %d", ret);
382 return ret;
383 }
384
385 /*
386 * initialise /proc/fs/afs/<cell>/
387 */
afs_proc_cell_setup(struct afs_cell * cell)388 int afs_proc_cell_setup(struct afs_cell *cell)
389 {
390 struct proc_dir_entry *p;
391
392 _enter("%p{%s}", cell, cell->name);
393
394 cell->proc_dir = proc_mkdir(cell->name, proc_afs);
395 if (!cell->proc_dir)
396 goto error_dir;
397
398 p = proc_create_data("servers", 0, cell->proc_dir,
399 &afs_proc_cell_servers_fops, cell);
400 if (!p)
401 goto error_servers;
402
403 p = proc_create_data("vlservers", 0, cell->proc_dir,
404 &afs_proc_cell_vlservers_fops, cell);
405 if (!p)
406 goto error_vlservers;
407
408 p = proc_create_data("volumes", 0, cell->proc_dir,
409 &afs_proc_cell_volumes_fops, cell);
410 if (!p)
411 goto error_volumes;
412
413 _leave(" = 0");
414 return 0;
415
416 error_volumes:
417 remove_proc_entry("vlservers", cell->proc_dir);
418 error_vlservers:
419 remove_proc_entry("servers", cell->proc_dir);
420 error_servers:
421 remove_proc_entry(cell->name, proc_afs);
422 error_dir:
423 _leave(" = -ENOMEM");
424 return -ENOMEM;
425 }
426
427 /*
428 * remove /proc/fs/afs/<cell>/
429 */
afs_proc_cell_remove(struct afs_cell * cell)430 void afs_proc_cell_remove(struct afs_cell *cell)
431 {
432 _enter("");
433
434 remove_proc_entry("volumes", cell->proc_dir);
435 remove_proc_entry("vlservers", cell->proc_dir);
436 remove_proc_entry("servers", cell->proc_dir);
437 remove_proc_entry(cell->name, proc_afs);
438
439 _leave("");
440 }
441
442 /*
443 * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
444 */
afs_proc_cell_volumes_open(struct inode * inode,struct file * file)445 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
446 {
447 struct afs_cell *cell;
448 struct seq_file *m;
449 int ret;
450
451 cell = PDE(inode)->data;
452 if (!cell)
453 return -ENOENT;
454
455 ret = seq_open(file, &afs_proc_cell_volumes_ops);
456 if (ret < 0)
457 return ret;
458
459 m = file->private_data;
460 m->private = cell;
461
462 return 0;
463 }
464
465 /*
466 * close the file and release the ref to the cell
467 */
afs_proc_cell_volumes_release(struct inode * inode,struct file * file)468 static int afs_proc_cell_volumes_release(struct inode *inode, struct file *file)
469 {
470 return seq_release(inode, file);
471 }
472
473 /*
474 * set up the iterator to start reading from the cells list and return the
475 * first item
476 */
afs_proc_cell_volumes_start(struct seq_file * m,loff_t * _pos)477 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
478 {
479 struct afs_cell *cell = m->private;
480
481 _enter("cell=%p pos=%Ld", cell, *_pos);
482
483 /* lock the list against modification */
484 down_read(&cell->vl_sem);
485 return seq_list_start_head(&cell->vl_list, *_pos);
486 }
487
488 /*
489 * move to next cell in cells list
490 */
afs_proc_cell_volumes_next(struct seq_file * p,void * v,loff_t * _pos)491 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
492 loff_t *_pos)
493 {
494 struct afs_cell *cell = p->private;
495
496 _enter("cell=%p pos=%Ld", cell, *_pos);
497 return seq_list_next(v, &cell->vl_list, _pos);
498 }
499
500 /*
501 * clean up after reading from the cells list
502 */
afs_proc_cell_volumes_stop(struct seq_file * p,void * v)503 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
504 {
505 struct afs_cell *cell = p->private;
506
507 up_read(&cell->vl_sem);
508 }
509
510 static const char afs_vlocation_states[][4] = {
511 [AFS_VL_NEW] = "New",
512 [AFS_VL_CREATING] = "Crt",
513 [AFS_VL_VALID] = "Val",
514 [AFS_VL_NO_VOLUME] = "NoV",
515 [AFS_VL_UPDATING] = "Upd",
516 [AFS_VL_VOLUME_DELETED] = "Del",
517 [AFS_VL_UNCERTAIN] = "Unc",
518 };
519
520 /*
521 * display a header line followed by a load of volume lines
522 */
afs_proc_cell_volumes_show(struct seq_file * m,void * v)523 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
524 {
525 struct afs_cell *cell = m->private;
526 struct afs_vlocation *vlocation =
527 list_entry(v, struct afs_vlocation, link);
528
529 /* display header on line 1 */
530 if (v == &cell->vl_list) {
531 seq_puts(m, "USE STT VLID[0] VLID[1] VLID[2] NAME\n");
532 return 0;
533 }
534
535 /* display one cell per line on subsequent lines */
536 seq_printf(m, "%3d %s %08x %08x %08x %s\n",
537 atomic_read(&vlocation->usage),
538 afs_vlocation_states[vlocation->state],
539 vlocation->vldb.vid[0],
540 vlocation->vldb.vid[1],
541 vlocation->vldb.vid[2],
542 vlocation->vldb.name);
543
544 return 0;
545 }
546
547 /*
548 * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
549 * location server
550 */
afs_proc_cell_vlservers_open(struct inode * inode,struct file * file)551 static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
552 {
553 struct afs_cell *cell;
554 struct seq_file *m;
555 int ret;
556
557 cell = PDE(inode)->data;
558 if (!cell)
559 return -ENOENT;
560
561 ret = seq_open(file, &afs_proc_cell_vlservers_ops);
562 if (ret<0)
563 return ret;
564
565 m = file->private_data;
566 m->private = cell;
567
568 return 0;
569 }
570
571 /*
572 * close the file and release the ref to the cell
573 */
afs_proc_cell_vlservers_release(struct inode * inode,struct file * file)574 static int afs_proc_cell_vlservers_release(struct inode *inode,
575 struct file *file)
576 {
577 return seq_release(inode, file);
578 }
579
580 /*
581 * set up the iterator to start reading from the cells list and return the
582 * first item
583 */
afs_proc_cell_vlservers_start(struct seq_file * m,loff_t * _pos)584 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
585 {
586 struct afs_cell *cell = m->private;
587 loff_t pos = *_pos;
588
589 _enter("cell=%p pos=%Ld", cell, *_pos);
590
591 /* lock the list against modification */
592 down_read(&cell->vl_sem);
593
594 /* allow for the header line */
595 if (!pos)
596 return (void *) 1;
597 pos--;
598
599 if (pos >= cell->vl_naddrs)
600 return NULL;
601
602 return &cell->vl_addrs[pos];
603 }
604
605 /*
606 * move to next cell in cells list
607 */
afs_proc_cell_vlservers_next(struct seq_file * p,void * v,loff_t * _pos)608 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
609 loff_t *_pos)
610 {
611 struct afs_cell *cell = p->private;
612 loff_t pos;
613
614 _enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
615
616 pos = *_pos;
617 (*_pos)++;
618 if (pos >= cell->vl_naddrs)
619 return NULL;
620
621 return &cell->vl_addrs[pos];
622 }
623
624 /*
625 * clean up after reading from the cells list
626 */
afs_proc_cell_vlservers_stop(struct seq_file * p,void * v)627 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
628 {
629 struct afs_cell *cell = p->private;
630
631 up_read(&cell->vl_sem);
632 }
633
634 /*
635 * display a header line followed by a load of volume lines
636 */
afs_proc_cell_vlservers_show(struct seq_file * m,void * v)637 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
638 {
639 struct in_addr *addr = v;
640
641 /* display header on line 1 */
642 if (v == (struct in_addr *) 1) {
643 seq_puts(m, "ADDRESS\n");
644 return 0;
645 }
646
647 /* display one cell per line on subsequent lines */
648 seq_printf(m, "%pI4\n", &addr->s_addr);
649 return 0;
650 }
651
652 /*
653 * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
654 * servers
655 */
afs_proc_cell_servers_open(struct inode * inode,struct file * file)656 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
657 {
658 struct afs_cell *cell;
659 struct seq_file *m;
660 int ret;
661
662 cell = PDE(inode)->data;
663 if (!cell)
664 return -ENOENT;
665
666 ret = seq_open(file, &afs_proc_cell_servers_ops);
667 if (ret < 0)
668 return ret;
669
670 m = file->private_data;
671 m->private = cell;
672 return 0;
673 }
674
675 /*
676 * close the file and release the ref to the cell
677 */
afs_proc_cell_servers_release(struct inode * inode,struct file * file)678 static int afs_proc_cell_servers_release(struct inode *inode,
679 struct file *file)
680 {
681 return seq_release(inode, file);
682 }
683
684 /*
685 * set up the iterator to start reading from the cells list and return the
686 * first item
687 */
afs_proc_cell_servers_start(struct seq_file * m,loff_t * _pos)688 static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
689 __acquires(m->private->servers_lock)
690 {
691 struct afs_cell *cell = m->private;
692
693 _enter("cell=%p pos=%Ld", cell, *_pos);
694
695 /* lock the list against modification */
696 read_lock(&cell->servers_lock);
697 return seq_list_start_head(&cell->servers, *_pos);
698 }
699
700 /*
701 * move to next cell in cells list
702 */
afs_proc_cell_servers_next(struct seq_file * p,void * v,loff_t * _pos)703 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
704 loff_t *_pos)
705 {
706 struct afs_cell *cell = p->private;
707
708 _enter("cell=%p pos=%Ld", cell, *_pos);
709 return seq_list_next(v, &cell->servers, _pos);
710 }
711
712 /*
713 * clean up after reading from the cells list
714 */
afs_proc_cell_servers_stop(struct seq_file * p,void * v)715 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
716 __releases(p->private->servers_lock)
717 {
718 struct afs_cell *cell = p->private;
719
720 read_unlock(&cell->servers_lock);
721 }
722
723 /*
724 * display a header line followed by a load of volume lines
725 */
afs_proc_cell_servers_show(struct seq_file * m,void * v)726 static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
727 {
728 struct afs_cell *cell = m->private;
729 struct afs_server *server = list_entry(v, struct afs_server, link);
730 char ipaddr[20];
731
732 /* display header on line 1 */
733 if (v == &cell->servers) {
734 seq_puts(m, "USE ADDR STATE\n");
735 return 0;
736 }
737
738 /* display one cell per line on subsequent lines */
739 sprintf(ipaddr, "%pI4", &server->addr);
740 seq_printf(m, "%3d %-15.15s %5d\n",
741 atomic_read(&server->usage), ipaddr, server->fs_state);
742
743 return 0;
744 }
745