blob: 101d21b6c03715b45ead510a2abccb706f23d209 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/* proc.c: /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/sched.h>
13#include <linux/slab.h>
14#include <linux/module.h>
15#include <linux/proc_fs.h>
16#include <linux/seq_file.h>
17#include "cell.h"
18#include "volume.h"
19#include <asm/uaccess.h>
20#include "internal.h"
21
22static struct proc_dir_entry *proc_afs;
23
24
25static int afs_proc_cells_open(struct inode *inode, struct file *file);
26static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
27static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
28static void afs_proc_cells_stop(struct seq_file *p, void *v);
29static int afs_proc_cells_show(struct seq_file *m, void *v);
30static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
31 size_t size, loff_t *_pos);
32
33static struct seq_operations afs_proc_cells_ops = {
34 .start = afs_proc_cells_start,
35 .next = afs_proc_cells_next,
36 .stop = afs_proc_cells_stop,
37 .show = afs_proc_cells_show,
38};
39
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080040static const struct file_operations afs_proc_cells_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 .open = afs_proc_cells_open,
42 .read = seq_read,
43 .write = afs_proc_cells_write,
44 .llseek = seq_lseek,
45 .release = seq_release,
46};
47
48static int afs_proc_rootcell_open(struct inode *inode, struct file *file);
49static int afs_proc_rootcell_release(struct inode *inode, struct file *file);
50static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
51 size_t size, loff_t *_pos);
52static ssize_t afs_proc_rootcell_write(struct file *file,
53 const char __user *buf,
54 size_t size, loff_t *_pos);
55
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080056static const struct file_operations afs_proc_rootcell_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 .open = afs_proc_rootcell_open,
58 .read = afs_proc_rootcell_read,
59 .write = afs_proc_rootcell_write,
60 .llseek = no_llseek,
61 .release = afs_proc_rootcell_release
62};
63
64static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
65static int afs_proc_cell_volumes_release(struct inode *inode,
66 struct file *file);
67static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
68static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
69 loff_t *pos);
70static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
71static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
72
73static 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
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080080static const struct file_operations afs_proc_cell_volumes_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 .open = afs_proc_cell_volumes_open,
82 .read = seq_read,
83 .llseek = seq_lseek,
84 .release = afs_proc_cell_volumes_release,
85};
86
87static int afs_proc_cell_vlservers_open(struct inode *inode,
88 struct file *file);
89static int afs_proc_cell_vlservers_release(struct inode *inode,
90 struct file *file);
91static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
92static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
93 loff_t *pos);
94static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
95static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
96
97static struct seq_operations afs_proc_cell_vlservers_ops = {
98 .start = afs_proc_cell_vlservers_start,
99 .next = afs_proc_cell_vlservers_next,
100 .stop = afs_proc_cell_vlservers_stop,
101 .show = afs_proc_cell_vlservers_show,
102};
103
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800104static const struct file_operations afs_proc_cell_vlservers_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 .open = afs_proc_cell_vlservers_open,
106 .read = seq_read,
107 .llseek = seq_lseek,
108 .release = afs_proc_cell_vlservers_release,
109};
110
111static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
112static int afs_proc_cell_servers_release(struct inode *inode,
113 struct file *file);
114static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
115static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
116 loff_t *pos);
117static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
118static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
119
120static struct seq_operations afs_proc_cell_servers_ops = {
121 .start = afs_proc_cell_servers_start,
122 .next = afs_proc_cell_servers_next,
123 .stop = afs_proc_cell_servers_stop,
124 .show = afs_proc_cell_servers_show,
125};
126
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -0800127static const struct file_operations afs_proc_cell_servers_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 .open = afs_proc_cell_servers_open,
129 .read = seq_read,
130 .llseek = seq_lseek,
131 .release = afs_proc_cell_servers_release,
132};
133
134/*****************************************************************************/
135/*
136 * initialise the /proc/fs/afs/ directory
137 */
138int afs_proc_init(void)
139{
140 struct proc_dir_entry *p;
141
142 _enter("");
143
144 proc_afs = proc_mkdir("fs/afs", NULL);
145 if (!proc_afs)
146 goto error;
147 proc_afs->owner = THIS_MODULE;
148
149 p = create_proc_entry("cells", 0, proc_afs);
150 if (!p)
151 goto error_proc;
152 p->proc_fops = &afs_proc_cells_fops;
153 p->owner = THIS_MODULE;
154
155 p = create_proc_entry("rootcell", 0, proc_afs);
156 if (!p)
157 goto error_cells;
158 p->proc_fops = &afs_proc_rootcell_fops;
159 p->owner = THIS_MODULE;
160
161 _leave(" = 0");
162 return 0;
163
164 error_cells:
165 remove_proc_entry("cells", proc_afs);
166 error_proc:
167 remove_proc_entry("fs/afs", NULL);
168 error:
169 _leave(" = -ENOMEM");
170 return -ENOMEM;
171
172} /* end afs_proc_init() */
173
174/*****************************************************************************/
175/*
176 * clean up the /proc/fs/afs/ directory
177 */
178void afs_proc_cleanup(void)
179{
180 remove_proc_entry("cells", proc_afs);
181
182 remove_proc_entry("fs/afs", NULL);
183
184} /* end afs_proc_cleanup() */
185
186/*****************************************************************************/
187/*
188 * open "/proc/fs/afs/cells" which provides a summary of extant cells
189 */
190static int afs_proc_cells_open(struct inode *inode, struct file *file)
191{
192 struct seq_file *m;
193 int ret;
194
195 ret = seq_open(file, &afs_proc_cells_ops);
196 if (ret < 0)
197 return ret;
198
199 m = file->private_data;
200 m->private = PDE(inode)->data;
201
202 return 0;
203} /* end afs_proc_cells_open() */
204
205/*****************************************************************************/
206/*
207 * set up the iterator to start reading from the cells list and return the
208 * first item
209 */
210static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
211{
212 struct list_head *_p;
213 loff_t pos = *_pos;
214
215 /* lock the list against modification */
216 down_read(&afs_proc_cells_sem);
217
218 /* allow for the header line */
219 if (!pos)
220 return (void *) 1;
221 pos--;
222
223 /* find the n'th element in the list */
224 list_for_each(_p, &afs_proc_cells)
225 if (!pos--)
226 break;
227
228 return _p != &afs_proc_cells ? _p : NULL;
229} /* end afs_proc_cells_start() */
230
231/*****************************************************************************/
232/*
233 * move to next cell in cells list
234 */
235static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
236{
237 struct list_head *_p;
238
239 (*pos)++;
240
241 _p = v;
242 _p = v == (void *) 1 ? afs_proc_cells.next : _p->next;
243
244 return _p != &afs_proc_cells ? _p : NULL;
245} /* end afs_proc_cells_next() */
246
247/*****************************************************************************/
248/*
249 * clean up after reading from the cells list
250 */
251static void afs_proc_cells_stop(struct seq_file *p, void *v)
252{
253 up_read(&afs_proc_cells_sem);
254
255} /* end afs_proc_cells_stop() */
256
257/*****************************************************************************/
258/*
259 * display a header line followed by a load of cell lines
260 */
261static int afs_proc_cells_show(struct seq_file *m, void *v)
262{
263 struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
264
265 /* display header on line 1 */
266 if (v == (void *) 1) {
267 seq_puts(m, "USE NAME\n");
268 return 0;
269 }
270
271 /* display one cell per line on subsequent lines */
272 seq_printf(m, "%3d %s\n", atomic_read(&cell->usage), cell->name);
273
274 return 0;
275} /* end afs_proc_cells_show() */
276
277/*****************************************************************************/
278/*
279 * handle writes to /proc/fs/afs/cells
280 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
281 */
282static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
283 size_t size, loff_t *_pos)
284{
285 char *kbuf, *name, *args;
286 int ret;
287
288 /* start by dragging the command into memory */
289 if (size <= 1 || size >= PAGE_SIZE)
290 return -EINVAL;
291
292 kbuf = kmalloc(size + 1, GFP_KERNEL);
293 if (!kbuf)
294 return -ENOMEM;
295
296 ret = -EFAULT;
297 if (copy_from_user(kbuf, buf, size) != 0)
298 goto done;
299 kbuf[size] = 0;
300
301 /* trim to first NL */
302 name = memchr(kbuf, '\n', size);
303 if (name)
304 *name = 0;
305
306 /* split into command, name and argslist */
307 name = strchr(kbuf, ' ');
308 if (!name)
309 goto inval;
310 do {
311 *name++ = 0;
312 } while(*name == ' ');
313 if (!*name)
314 goto inval;
315
316 args = strchr(name, ' ');
317 if (!args)
318 goto inval;
319 do {
320 *args++ = 0;
321 } while(*args == ' ');
322 if (!*args)
323 goto inval;
324
325 /* determine command to perform */
326 _debug("cmd=%s name=%s args=%s", kbuf, name, args);
327
328 if (strcmp(kbuf, "add") == 0) {
329 struct afs_cell *cell;
330 ret = afs_cell_create(name, args, &cell);
331 if (ret < 0)
332 goto done;
333
334 printk("kAFS: Added new cell '%s'\n", name);
335 }
336 else {
337 goto inval;
338 }
339
340 ret = size;
341
342 done:
343 kfree(kbuf);
344 _leave(" = %d", ret);
345 return ret;
346
347 inval:
348 ret = -EINVAL;
349 printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
350 goto done;
351} /* end afs_proc_cells_write() */
352
353/*****************************************************************************/
354/*
355 * Stubs for /proc/fs/afs/rootcell
356 */
357static int afs_proc_rootcell_open(struct inode *inode, struct file *file)
358{
359 return 0;
360}
361
362static int afs_proc_rootcell_release(struct inode *inode, struct file *file)
363{
364 return 0;
365}
366
367static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
368 size_t size, loff_t *_pos)
369{
370 return 0;
371}
372
373/*****************************************************************************/
374/*
375 * handle writes to /proc/fs/afs/rootcell
376 * - to initialize rootcell: echo "cell.name:192.168.231.14"
377 */
378static ssize_t afs_proc_rootcell_write(struct file *file,
379 const char __user *buf,
380 size_t size, loff_t *_pos)
381{
382 char *kbuf, *s;
383 int ret;
384
385 /* start by dragging the command into memory */
386 if (size <= 1 || size >= PAGE_SIZE)
387 return -EINVAL;
388
389 ret = -ENOMEM;
390 kbuf = kmalloc(size + 1, GFP_KERNEL);
391 if (!kbuf)
392 goto nomem;
393
394 ret = -EFAULT;
395 if (copy_from_user(kbuf, buf, size) != 0)
396 goto infault;
397 kbuf[size] = 0;
398
399 /* trim to first NL */
400 s = memchr(kbuf, '\n', size);
401 if (s)
402 *s = 0;
403
404 /* determine command to perform */
405 _debug("rootcell=%s", kbuf);
406
407 ret = afs_cell_init(kbuf);
408 if (ret >= 0)
409 ret = size; /* consume everything, always */
410
411 infault:
412 kfree(kbuf);
413 nomem:
414 _leave(" = %d", ret);
415 return ret;
416} /* end afs_proc_rootcell_write() */
417
418/*****************************************************************************/
419/*
420 * initialise /proc/fs/afs/<cell>/
421 */
422int afs_proc_cell_setup(struct afs_cell *cell)
423{
424 struct proc_dir_entry *p;
425
426 _enter("%p{%s}", cell, cell->name);
427
428 cell->proc_dir = proc_mkdir(cell->name, proc_afs);
429 if (!cell->proc_dir)
430 return -ENOMEM;
431
432 p = create_proc_entry("servers", 0, cell->proc_dir);
433 if (!p)
434 goto error_proc;
435 p->proc_fops = &afs_proc_cell_servers_fops;
436 p->owner = THIS_MODULE;
437 p->data = cell;
438
439 p = create_proc_entry("vlservers", 0, cell->proc_dir);
440 if (!p)
441 goto error_servers;
442 p->proc_fops = &afs_proc_cell_vlservers_fops;
443 p->owner = THIS_MODULE;
444 p->data = cell;
445
446 p = create_proc_entry("volumes", 0, cell->proc_dir);
447 if (!p)
448 goto error_vlservers;
449 p->proc_fops = &afs_proc_cell_volumes_fops;
450 p->owner = THIS_MODULE;
451 p->data = cell;
452
453 _leave(" = 0");
454 return 0;
455
456 error_vlservers:
457 remove_proc_entry("vlservers", cell->proc_dir);
458 error_servers:
459 remove_proc_entry("servers", cell->proc_dir);
460 error_proc:
461 remove_proc_entry(cell->name, proc_afs);
462 _leave(" = -ENOMEM");
463 return -ENOMEM;
464} /* end afs_proc_cell_setup() */
465
466/*****************************************************************************/
467/*
468 * remove /proc/fs/afs/<cell>/
469 */
470void afs_proc_cell_remove(struct afs_cell *cell)
471{
472 _enter("");
473
474 remove_proc_entry("volumes", cell->proc_dir);
475 remove_proc_entry("vlservers", cell->proc_dir);
476 remove_proc_entry("servers", cell->proc_dir);
477 remove_proc_entry(cell->name, proc_afs);
478
479 _leave("");
480} /* end afs_proc_cell_remove() */
481
482/*****************************************************************************/
483/*
484 * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
485 */
486static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
487{
488 struct afs_cell *cell;
489 struct seq_file *m;
490 int ret;
491
492 cell = afs_get_cell_maybe((struct afs_cell **) &PDE(inode)->data);
493 if (!cell)
494 return -ENOENT;
495
496 ret = seq_open(file, &afs_proc_cell_volumes_ops);
497 if (ret < 0)
498 return ret;
499
500 m = file->private_data;
501 m->private = cell;
502
503 return 0;
504} /* end afs_proc_cell_volumes_open() */
505
506/*****************************************************************************/
507/*
508 * close the file and release the ref to the cell
509 */
510static int afs_proc_cell_volumes_release(struct inode *inode, struct file *file)
511{
512 struct afs_cell *cell = PDE(inode)->data;
513 int ret;
514
515 ret = seq_release(inode,file);
516
517 afs_put_cell(cell);
518
519 return ret;
520} /* end afs_proc_cell_volumes_release() */
521
522/*****************************************************************************/
523/*
524 * set up the iterator to start reading from the cells list and return the
525 * first item
526 */
527static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
528{
529 struct list_head *_p;
530 struct afs_cell *cell = m->private;
531 loff_t pos = *_pos;
532
533 _enter("cell=%p pos=%Ld", cell, *_pos);
534
535 /* lock the list against modification */
536 down_read(&cell->vl_sem);
537
538 /* allow for the header line */
539 if (!pos)
540 return (void *) 1;
541 pos--;
542
543 /* find the n'th element in the list */
544 list_for_each(_p, &cell->vl_list)
545 if (!pos--)
546 break;
547
548 return _p != &cell->vl_list ? _p : NULL;
549} /* end afs_proc_cell_volumes_start() */
550
551/*****************************************************************************/
552/*
553 * move to next cell in cells list
554 */
555static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
556 loff_t *_pos)
557{
558 struct list_head *_p;
559 struct afs_cell *cell = p->private;
560
561 _enter("cell=%p pos=%Ld", cell, *_pos);
562
563 (*_pos)++;
564
565 _p = v;
566 _p = v == (void *) 1 ? cell->vl_list.next : _p->next;
567
568 return _p != &cell->vl_list ? _p : NULL;
569} /* end afs_proc_cell_volumes_next() */
570
571/*****************************************************************************/
572/*
573 * clean up after reading from the cells list
574 */
575static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
576{
577 struct afs_cell *cell = p->private;
578
579 up_read(&cell->vl_sem);
580
581} /* end afs_proc_cell_volumes_stop() */
582
583/*****************************************************************************/
584/*
585 * display a header line followed by a load of volume lines
586 */
587static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
588{
589 struct afs_vlocation *vlocation =
590 list_entry(v, struct afs_vlocation, link);
591
592 /* display header on line 1 */
593 if (v == (void *) 1) {
594 seq_puts(m, "USE VLID[0] VLID[1] VLID[2] NAME\n");
595 return 0;
596 }
597
598 /* display one cell per line on subsequent lines */
599 seq_printf(m, "%3d %08x %08x %08x %s\n",
600 atomic_read(&vlocation->usage),
601 vlocation->vldb.vid[0],
602 vlocation->vldb.vid[1],
603 vlocation->vldb.vid[2],
604 vlocation->vldb.name
605 );
606
607 return 0;
608} /* end afs_proc_cell_volumes_show() */
609
610/*****************************************************************************/
611/*
612 * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
613 * location server
614 */
615static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
616{
617 struct afs_cell *cell;
618 struct seq_file *m;
619 int ret;
620
621 cell = afs_get_cell_maybe((struct afs_cell**)&PDE(inode)->data);
622 if (!cell)
623 return -ENOENT;
624
625 ret = seq_open(file,&afs_proc_cell_vlservers_ops);
626 if (ret<0)
627 return ret;
628
629 m = file->private_data;
630 m->private = cell;
631
632 return 0;
633} /* end afs_proc_cell_vlservers_open() */
634
635/*****************************************************************************/
636/*
637 * close the file and release the ref to the cell
638 */
639static int afs_proc_cell_vlservers_release(struct inode *inode,
640 struct file *file)
641{
642 struct afs_cell *cell = PDE(inode)->data;
643 int ret;
644
645 ret = seq_release(inode,file);
646
647 afs_put_cell(cell);
648
649 return ret;
650} /* end afs_proc_cell_vlservers_release() */
651
652/*****************************************************************************/
653/*
654 * set up the iterator to start reading from the cells list and return the
655 * first item
656 */
657static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
658{
659 struct afs_cell *cell = m->private;
660 loff_t pos = *_pos;
661
662 _enter("cell=%p pos=%Ld", cell, *_pos);
663
664 /* lock the list against modification */
665 down_read(&cell->vl_sem);
666
667 /* allow for the header line */
668 if (!pos)
669 return (void *) 1;
670 pos--;
671
672 if (pos >= cell->vl_naddrs)
673 return NULL;
674
675 return &cell->vl_addrs[pos];
676} /* end afs_proc_cell_vlservers_start() */
677
678/*****************************************************************************/
679/*
680 * move to next cell in cells list
681 */
682static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
683 loff_t *_pos)
684{
685 struct afs_cell *cell = p->private;
686 loff_t pos;
687
688 _enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
689
690 pos = *_pos;
691 (*_pos)++;
692 if (pos >= cell->vl_naddrs)
693 return NULL;
694
695 return &cell->vl_addrs[pos];
696} /* end afs_proc_cell_vlservers_next() */
697
698/*****************************************************************************/
699/*
700 * clean up after reading from the cells list
701 */
702static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
703{
704 struct afs_cell *cell = p->private;
705
706 up_read(&cell->vl_sem);
707
708} /* end afs_proc_cell_vlservers_stop() */
709
710/*****************************************************************************/
711/*
712 * display a header line followed by a load of volume lines
713 */
714static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
715{
716 struct in_addr *addr = v;
717
718 /* display header on line 1 */
719 if (v == (struct in_addr *) 1) {
720 seq_puts(m, "ADDRESS\n");
721 return 0;
722 }
723
724 /* display one cell per line on subsequent lines */
725 seq_printf(m, "%u.%u.%u.%u\n", NIPQUAD(addr->s_addr));
726
727 return 0;
728} /* end afs_proc_cell_vlservers_show() */
729
730/*****************************************************************************/
731/*
732 * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
733 * servers
734 */
735static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
736{
737 struct afs_cell *cell;
738 struct seq_file *m;
739 int ret;
740
741 cell = afs_get_cell_maybe((struct afs_cell **) &PDE(inode)->data);
742 if (!cell)
743 return -ENOENT;
744
745 ret = seq_open(file, &afs_proc_cell_servers_ops);
746 if (ret < 0)
747 return ret;
748
749 m = file->private_data;
750 m->private = cell;
751
752 return 0;
753} /* end afs_proc_cell_servers_open() */
754
755/*****************************************************************************/
756/*
757 * close the file and release the ref to the cell
758 */
759static int afs_proc_cell_servers_release(struct inode *inode,
760 struct file *file)
761{
762 struct afs_cell *cell = PDE(inode)->data;
763 int ret;
764
765 ret = seq_release(inode, file);
766
767 afs_put_cell(cell);
768
769 return ret;
770} /* end afs_proc_cell_servers_release() */
771
772/*****************************************************************************/
773/*
774 * set up the iterator to start reading from the cells list and return the
775 * first item
776 */
777static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
778{
779 struct list_head *_p;
780 struct afs_cell *cell = m->private;
781 loff_t pos = *_pos;
782
783 _enter("cell=%p pos=%Ld", cell, *_pos);
784
785 /* lock the list against modification */
786 read_lock(&cell->sv_lock);
787
788 /* allow for the header line */
789 if (!pos)
790 return (void *) 1;
791 pos--;
792
793 /* find the n'th element in the list */
794 list_for_each(_p, &cell->sv_list)
795 if (!pos--)
796 break;
797
798 return _p != &cell->sv_list ? _p : NULL;
799} /* end afs_proc_cell_servers_start() */
800
801/*****************************************************************************/
802/*
803 * move to next cell in cells list
804 */
805static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
806 loff_t *_pos)
807{
808 struct list_head *_p;
809 struct afs_cell *cell = p->private;
810
811 _enter("cell=%p pos=%Ld", cell, *_pos);
812
813 (*_pos)++;
814
815 _p = v;
816 _p = v == (void *) 1 ? cell->sv_list.next : _p->next;
817
818 return _p != &cell->sv_list ? _p : NULL;
819} /* end afs_proc_cell_servers_next() */
820
821/*****************************************************************************/
822/*
823 * clean up after reading from the cells list
824 */
825static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
826{
827 struct afs_cell *cell = p->private;
828
829 read_unlock(&cell->sv_lock);
830
831} /* end afs_proc_cell_servers_stop() */
832
833/*****************************************************************************/
834/*
835 * display a header line followed by a load of volume lines
836 */
837static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
838{
839 struct afs_server *server = list_entry(v, struct afs_server, link);
840 char ipaddr[20];
841
842 /* display header on line 1 */
843 if (v == (void *) 1) {
844 seq_puts(m, "USE ADDR STATE\n");
845 return 0;
846 }
847
848 /* display one cell per line on subsequent lines */
849 sprintf(ipaddr, "%u.%u.%u.%u", NIPQUAD(server->addr));
850 seq_printf(m, "%3d %-15.15s %5d\n",
851 atomic_read(&server->usage),
852 ipaddr,
853 server->fs_state
854 );
855
856 return 0;
857} /* end afs_proc_cell_servers_show() */