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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 <linux/uaccess.h>
18#include "internal.h"
19
20static inline struct afs_net *afs_proc2net(struct file *f)
21{
22 return &__afs_net;
23}
24
25static inline struct afs_net *afs_seq2net(struct seq_file *m)
26{
27 return &__afs_net; // TODO: use seq_file_net(m)
28}
29
30static int afs_proc_cells_open(struct inode *inode, struct file *file);
31static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
32static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
33static void afs_proc_cells_stop(struct seq_file *p, void *v);
34static int afs_proc_cells_show(struct seq_file *m, void *v);
35static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
36 size_t size, loff_t *_pos);
37
38static const struct seq_operations afs_proc_cells_ops = {
39 .start = afs_proc_cells_start,
40 .next = afs_proc_cells_next,
41 .stop = afs_proc_cells_stop,
42 .show = afs_proc_cells_show,
43};
44
45static const struct file_operations afs_proc_cells_fops = {
46 .open = afs_proc_cells_open,
47 .read = seq_read,
48 .write = afs_proc_cells_write,
49 .llseek = seq_lseek,
50 .release = seq_release,
51};
52
53static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
54 size_t size, loff_t *_pos);
55static ssize_t afs_proc_rootcell_write(struct file *file,
56 const char __user *buf,
57 size_t size, loff_t *_pos);
58
59static const struct file_operations afs_proc_rootcell_fops = {
60 .read = afs_proc_rootcell_read,
61 .write = afs_proc_rootcell_write,
62 .llseek = no_llseek,
63};
64
65static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
66static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
67static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
68 loff_t *pos);
69static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
70static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
71
72static const struct seq_operations afs_proc_cell_volumes_ops = {
73 .start = afs_proc_cell_volumes_start,
74 .next = afs_proc_cell_volumes_next,
75 .stop = afs_proc_cell_volumes_stop,
76 .show = afs_proc_cell_volumes_show,
77};
78
79static const struct file_operations afs_proc_cell_volumes_fops = {
80 .open = afs_proc_cell_volumes_open,
81 .read = seq_read,
82 .llseek = seq_lseek,
83 .release = seq_release,
84};
85
86static int afs_proc_cell_vlservers_open(struct inode *inode,
87 struct file *file);
88static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
89static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
90 loff_t *pos);
91static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
92static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
93
94static const struct seq_operations afs_proc_cell_vlservers_ops = {
95 .start = afs_proc_cell_vlservers_start,
96 .next = afs_proc_cell_vlservers_next,
97 .stop = afs_proc_cell_vlservers_stop,
98 .show = afs_proc_cell_vlservers_show,
99};
100
101static const struct file_operations afs_proc_cell_vlservers_fops = {
102 .open = afs_proc_cell_vlservers_open,
103 .read = seq_read,
104 .llseek = seq_lseek,
105 .release = seq_release,
106};
107
108static int afs_proc_servers_open(struct inode *inode, struct file *file);
109static void *afs_proc_servers_start(struct seq_file *p, loff_t *pos);
110static void *afs_proc_servers_next(struct seq_file *p, void *v,
111 loff_t *pos);
112static void afs_proc_servers_stop(struct seq_file *p, void *v);
113static int afs_proc_servers_show(struct seq_file *m, void *v);
114
115static const struct seq_operations afs_proc_servers_ops = {
116 .start = afs_proc_servers_start,
117 .next = afs_proc_servers_next,
118 .stop = afs_proc_servers_stop,
119 .show = afs_proc_servers_show,
120};
121
122static const struct file_operations afs_proc_servers_fops = {
123 .open = afs_proc_servers_open,
124 .read = seq_read,
125 .llseek = seq_lseek,
126 .release = seq_release,
127};
128
129static int afs_proc_sysname_open(struct inode *inode, struct file *file);
130static int afs_proc_sysname_release(struct inode *inode, struct file *file);
131static void *afs_proc_sysname_start(struct seq_file *p, loff_t *pos);
132static void *afs_proc_sysname_next(struct seq_file *p, void *v,
133 loff_t *pos);
134static void afs_proc_sysname_stop(struct seq_file *p, void *v);
135static int afs_proc_sysname_show(struct seq_file *m, void *v);
136static ssize_t afs_proc_sysname_write(struct file *file,
137 const char __user *buf,
138 size_t size, loff_t *_pos);
139
140static const struct seq_operations afs_proc_sysname_ops = {
141 .start = afs_proc_sysname_start,
142 .next = afs_proc_sysname_next,
143 .stop = afs_proc_sysname_stop,
144 .show = afs_proc_sysname_show,
145};
146
147static const struct file_operations afs_proc_sysname_fops = {
148 .open = afs_proc_sysname_open,
149 .read = seq_read,
150 .llseek = seq_lseek,
151 .release = afs_proc_sysname_release,
152 .write = afs_proc_sysname_write,
153};
154
155static const struct file_operations afs_proc_stats_fops;
156
157/*
158 * initialise the /proc/fs/afs/ directory
159 */
160int afs_proc_init(struct afs_net *net)
161{
162 _enter("");
163
164 net->proc_afs = proc_mkdir("fs/afs", NULL);
165 if (!net->proc_afs)
166 goto error_dir;
167
168 if (!proc_create("cells", 0644, net->proc_afs, &afs_proc_cells_fops) ||
169 !proc_create("rootcell", 0644, net->proc_afs, &afs_proc_rootcell_fops) ||
170 !proc_create("servers", 0644, net->proc_afs, &afs_proc_servers_fops) ||
171 !proc_create("stats", 0644, net->proc_afs, &afs_proc_stats_fops) ||
172 !proc_create("sysname", 0644, net->proc_afs, &afs_proc_sysname_fops))
173 goto error_tree;
174
175 _leave(" = 0");
176 return 0;
177
178error_tree:
179 proc_remove(net->proc_afs);
180error_dir:
181 _leave(" = -ENOMEM");
182 return -ENOMEM;
183}
184
185/*
186 * clean up the /proc/fs/afs/ directory
187 */
188void afs_proc_cleanup(struct afs_net *net)
189{
190 proc_remove(net->proc_afs);
191 net->proc_afs = NULL;
192}
193
194/*
195 * open "/proc/fs/afs/cells" which provides a summary of extant cells
196 */
197static int afs_proc_cells_open(struct inode *inode, struct file *file)
198{
199 struct seq_file *m;
200 int ret;
201
202 ret = seq_open(file, &afs_proc_cells_ops);
203 if (ret < 0)
204 return ret;
205
206 m = file->private_data;
207 m->private = PDE_DATA(inode);
208 return 0;
209}
210
211/*
212 * set up the iterator to start reading from the cells list and return the
213 * first item
214 */
215static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
216 __acquires(rcu)
217{
218 struct afs_net *net = afs_seq2net(m);
219
220 rcu_read_lock();
221 return seq_list_start_head(&net->proc_cells, *_pos);
222}
223
224/*
225 * move to next cell in cells list
226 */
227static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)
228{
229 struct afs_net *net = afs_seq2net(m);
230
231 return seq_list_next(v, &net->proc_cells, pos);
232}
233
234/*
235 * clean up after reading from the cells list
236 */
237static void afs_proc_cells_stop(struct seq_file *m, void *v)
238 __releases(rcu)
239{
240 rcu_read_unlock();
241}
242
243/*
244 * display a header line followed by a load of cell lines
245 */
246static int afs_proc_cells_show(struct seq_file *m, void *v)
247{
248 struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
249 struct afs_net *net = afs_seq2net(m);
250
251 if (v == &net->proc_cells) {
252 /* display header on line 1 */
253 seq_puts(m, "USE NAME\n");
254 return 0;
255 }
256
257 /* display one cell per line on subsequent lines */
258 seq_printf(m, "%3u %s\n", atomic_read(&cell->usage), cell->name);
259 return 0;
260}
261
262/*
263 * handle writes to /proc/fs/afs/cells
264 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
265 */
266static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
267 size_t size, loff_t *_pos)
268{
269 struct afs_net *net = afs_proc2net(file);
270 char *kbuf, *name, *args;
271 int ret;
272
273 /* start by dragging the command into memory */
274 if (size <= 1 || size >= PAGE_SIZE)
275 return -EINVAL;
276
277 kbuf = memdup_user_nul(buf, size);
278 if (IS_ERR(kbuf))
279 return PTR_ERR(kbuf);
280
281 /* trim to first NL */
282 name = memchr(kbuf, '\n', size);
283 if (name)
284 *name = 0;
285
286 /* split into command, name and argslist */
287 name = strchr(kbuf, ' ');
288 if (!name)
289 goto inval;
290 do {
291 *name++ = 0;
292 } while(*name == ' ');
293 if (!*name)
294 goto inval;
295
296 args = strchr(name, ' ');
297 if (!args)
298 goto inval;
299 do {
300 *args++ = 0;
301 } while(*args == ' ');
302 if (!*args)
303 goto inval;
304
305 /* determine command to perform */
306 _debug("cmd=%s name=%s args=%s", kbuf, name, args);
307
308 if (strcmp(kbuf, "add") == 0) {
309 struct afs_cell *cell;
310
311 cell = afs_lookup_cell(net, name, strlen(name), args, true);
312 if (IS_ERR(cell)) {
313 ret = PTR_ERR(cell);
314 goto done;
315 }
316
317 if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags))
318 afs_put_cell(net, cell);
319 printk("kAFS: Added new cell '%s'\n", name);
320 } else {
321 goto inval;
322 }
323
324 ret = size;
325
326done:
327 kfree(kbuf);
328 _leave(" = %d", ret);
329 return ret;
330
331inval:
332 ret = -EINVAL;
333 printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
334 goto done;
335}
336
337static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
338 size_t size, loff_t *_pos)
339{
340 struct afs_cell *cell;
341 struct afs_net *net = afs_proc2net(file);
342 unsigned int seq = 0;
343 char name[AFS_MAXCELLNAME + 1];
344 int len;
345
346 if (*_pos > 0)
347 return 0;
348 if (!net->ws_cell)
349 return 0;
350
351 rcu_read_lock();
352 do {
353 read_seqbegin_or_lock(&net->cells_lock, &seq);
354 len = 0;
355 cell = rcu_dereference_raw(net->ws_cell);
356 if (cell) {
357 len = cell->name_len;
358 memcpy(name, cell->name, len);
359 }
360 } while (need_seqretry(&net->cells_lock, seq));
361 done_seqretry(&net->cells_lock, seq);
362 rcu_read_unlock();
363
364 if (!len)
365 return 0;
366
367 name[len++] = '\n';
368 if (len > size)
369 len = size;
370 if (copy_to_user(buf, name, len) != 0)
371 return -EFAULT;
372 *_pos = 1;
373 return len;
374}
375
376/*
377 * handle writes to /proc/fs/afs/rootcell
378 * - to initialize rootcell: echo "cell.name:192.168.231.14"
379 */
380static ssize_t afs_proc_rootcell_write(struct file *file,
381 const char __user *buf,
382 size_t size, loff_t *_pos)
383{
384 struct afs_net *net = afs_proc2net(file);
385 char *kbuf, *s;
386 int ret;
387
388 /* start by dragging the command into memory */
389 if (size <= 1 || size >= PAGE_SIZE)
390 return -EINVAL;
391
392 kbuf = memdup_user_nul(buf, size);
393 if (IS_ERR(kbuf))
394 return PTR_ERR(kbuf);
395
396 ret = -EINVAL;
397 if (kbuf[0] == '.')
398 goto out;
399 if (memchr(kbuf, '/', size))
400 goto out;
401
402 /* trim to first NL */
403 s = memchr(kbuf, '\n', size);
404 if (s)
405 *s = 0;
406
407 /* determine command to perform */
408 _debug("rootcell=%s", kbuf);
409
410 ret = afs_cell_init(net, kbuf);
411 if (ret >= 0)
412 ret = size; /* consume everything, always */
413
414out:
415 kfree(kbuf);
416 _leave(" = %d", ret);
417 return ret;
418}
419
420/*
421 * initialise /proc/fs/afs/<cell>/
422 */
423int afs_proc_cell_setup(struct afs_net *net, struct afs_cell *cell)
424{
425 struct proc_dir_entry *dir;
426
427 _enter("%p{%s},%p", cell, cell->name, net->proc_afs);
428
429 dir = proc_mkdir(cell->name, net->proc_afs);
430 if (!dir)
431 goto error_dir;
432
433 if (!proc_create_data("vlservers", 0, dir,
434 &afs_proc_cell_vlservers_fops, cell) ||
435 !proc_create_data("volumes", 0, dir,
436 &afs_proc_cell_volumes_fops, cell))
437 goto error_tree;
438
439 _leave(" = 0");
440 return 0;
441
442error_tree:
443 remove_proc_subtree(cell->name, net->proc_afs);
444error_dir:
445 _leave(" = -ENOMEM");
446 return -ENOMEM;
447}
448
449/*
450 * remove /proc/fs/afs/<cell>/
451 */
452void afs_proc_cell_remove(struct afs_net *net, struct afs_cell *cell)
453{
454 _enter("");
455
456 remove_proc_subtree(cell->name, net->proc_afs);
457
458 _leave("");
459}
460
461/*
462 * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
463 */
464static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
465{
466 struct afs_cell *cell;
467 struct seq_file *m;
468 int ret;
469
470 cell = PDE_DATA(inode);
471 if (!cell)
472 return -ENOENT;
473
474 ret = seq_open(file, &afs_proc_cell_volumes_ops);
475 if (ret < 0)
476 return ret;
477
478 m = file->private_data;
479 m->private = cell;
480
481 return 0;
482}
483
484/*
485 * set up the iterator to start reading from the cells list and return the
486 * first item
487 */
488static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
489 __acquires(cell->proc_lock)
490{
491 struct afs_cell *cell = m->private;
492
493 _enter("cell=%p pos=%Ld", cell, *_pos);
494
495 read_lock(&cell->proc_lock);
496 return seq_list_start_head(&cell->proc_volumes, *_pos);
497}
498
499/*
500 * move to next cell in cells list
501 */
502static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
503 loff_t *_pos)
504{
505 struct afs_cell *cell = p->private;
506
507 _enter("cell=%p pos=%Ld", cell, *_pos);
508 return seq_list_next(v, &cell->proc_volumes, _pos);
509}
510
511/*
512 * clean up after reading from the cells list
513 */
514static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
515 __releases(cell->proc_lock)
516{
517 struct afs_cell *cell = p->private;
518
519 read_unlock(&cell->proc_lock);
520}
521
522static const char afs_vol_types[3][3] = {
523 [AFSVL_RWVOL] = "RW",
524 [AFSVL_ROVOL] = "RO",
525 [AFSVL_BACKVOL] = "BK",
526};
527
528/*
529 * display a header line followed by a load of volume lines
530 */
531static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
532{
533 struct afs_cell *cell = m->private;
534 struct afs_volume *vol = list_entry(v, struct afs_volume, proc_link);
535
536 /* Display header on line 1 */
537 if (v == &cell->proc_volumes) {
538 seq_puts(m, "USE VID TY\n");
539 return 0;
540 }
541
542 seq_printf(m, "%3d %08x %s\n",
543 atomic_read(&vol->usage), vol->vid,
544 afs_vol_types[vol->type]);
545
546 return 0;
547}
548
549/*
550 * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
551 * location server
552 */
553static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
554{
555 struct afs_cell *cell;
556 struct seq_file *m;
557 int ret;
558
559 cell = PDE_DATA(inode);
560 if (!cell)
561 return -ENOENT;
562
563 ret = seq_open(file, &afs_proc_cell_vlservers_ops);
564 if (ret<0)
565 return ret;
566
567 m = file->private_data;
568 m->private = cell;
569
570 return 0;
571}
572
573/*
574 * set up the iterator to start reading from the cells list and return the
575 * first item
576 */
577static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
578 __acquires(rcu)
579{
580 struct afs_addr_list *alist;
581 struct afs_cell *cell = m->private;
582 loff_t pos = *_pos;
583
584 rcu_read_lock();
585
586 alist = rcu_dereference(cell->vl_addrs);
587
588 /* allow for the header line */
589 if (!pos)
590 return (void *) 1;
591 pos--;
592
593 if (!alist || pos >= alist->nr_addrs)
594 return NULL;
595
596 return alist->addrs + pos;
597}
598
599/*
600 * move to next cell in cells list
601 */
602static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
603 loff_t *_pos)
604{
605 struct afs_addr_list *alist;
606 struct afs_cell *cell = p->private;
607 loff_t pos;
608
609 alist = rcu_dereference(cell->vl_addrs);
610
611 pos = *_pos;
612 (*_pos)++;
613 if (!alist || pos >= alist->nr_addrs)
614 return NULL;
615
616 return alist->addrs + pos;
617}
618
619/*
620 * clean up after reading from the cells list
621 */
622static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
623 __releases(rcu)
624{
625 rcu_read_unlock();
626}
627
628/*
629 * display a header line followed by a load of volume lines
630 */
631static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
632{
633 struct sockaddr_rxrpc *addr = v;
634
635 /* display header on line 1 */
636 if (v == (void *)1) {
637 seq_puts(m, "ADDRESS\n");
638 return 0;
639 }
640
641 /* display one cell per line on subsequent lines */
642 seq_printf(m, "%pISp\n", &addr->transport);
643 return 0;
644}
645
646/*
647 * open "/proc/fs/afs/servers" which provides a summary of active
648 * servers
649 */
650static int afs_proc_servers_open(struct inode *inode, struct file *file)
651{
652 return seq_open(file, &afs_proc_servers_ops);
653}
654
655/*
656 * Set up the iterator to start reading from the server list and return the
657 * first item.
658 */
659static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)
660 __acquires(rcu)
661{
662 struct afs_net *net = afs_seq2net(m);
663
664 rcu_read_lock();
665 return seq_hlist_start_head_rcu(&net->fs_proc, *_pos);
666}
667
668/*
669 * move to next cell in cells list
670 */
671static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)
672{
673 struct afs_net *net = afs_seq2net(m);
674
675 return seq_hlist_next_rcu(v, &net->fs_proc, _pos);
676}
677
678/*
679 * clean up after reading from the cells list
680 */
681static void afs_proc_servers_stop(struct seq_file *p, void *v)
682 __releases(rcu)
683{
684 rcu_read_unlock();
685}
686
687/*
688 * display a header line followed by a load of volume lines
689 */
690static int afs_proc_servers_show(struct seq_file *m, void *v)
691{
692 struct afs_server *server;
693 struct afs_addr_list *alist;
694
695 if (v == SEQ_START_TOKEN) {
696 seq_puts(m, "UUID USE ADDR\n");
697 return 0;
698 }
699
700 server = list_entry(v, struct afs_server, proc_link);
701 alist = rcu_dereference(server->addresses);
702 seq_printf(m, "%pU %3d %pISp\n",
703 &server->uuid,
704 atomic_read(&server->usage),
705 &alist->addrs[alist->index].transport);
706 return 0;
707}
708
709void afs_put_sysnames(struct afs_sysnames *sysnames)
710{
711 int i;
712
713 if (sysnames && refcount_dec_and_test(&sysnames->usage)) {
714 for (i = 0; i < sysnames->nr; i++)
715 if (sysnames->subs[i] != afs_init_sysname &&
716 sysnames->subs[i] != sysnames->blank)
717 kfree(sysnames->subs[i]);
718 }
719}
720
721/*
722 * Handle opening of /proc/fs/afs/sysname. If it is opened for writing, we
723 * assume the caller wants to change the substitution list and we allocate a
724 * buffer to hold the list.
725 */
726static int afs_proc_sysname_open(struct inode *inode, struct file *file)
727{
728 struct afs_sysnames *sysnames;
729 struct seq_file *m;
730 int ret;
731
732 ret = seq_open(file, &afs_proc_sysname_ops);
733 if (ret < 0)
734 return ret;
735
736 if (file->f_mode & FMODE_WRITE) {
737 sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
738 if (!sysnames) {
739 seq_release(inode, file);
740 return -ENOMEM;
741 }
742
743 refcount_set(&sysnames->usage, 1);
744 m = file->private_data;
745 m->private = sysnames;
746 }
747
748 return 0;
749}
750
751/*
752 * Handle writes to /proc/fs/afs/sysname to set the @sys substitution.
753 */
754static ssize_t afs_proc_sysname_write(struct file *file,
755 const char __user *buf,
756 size_t size, loff_t *_pos)
757{
758 struct afs_sysnames *sysnames;
759 struct seq_file *m = file->private_data;
760 char *kbuf = NULL, *s, *p, *sub;
761 int ret, len;
762
763 sysnames = m->private;
764 if (!sysnames)
765 return -EINVAL;
766 if (sysnames->error)
767 return sysnames->error;
768
769 if (size >= PAGE_SIZE - 1) {
770 sysnames->error = -EINVAL;
771 return -EINVAL;
772 }
773 if (size == 0)
774 return 0;
775
776 kbuf = memdup_user_nul(buf, size);
777 if (IS_ERR(kbuf))
778 return PTR_ERR(kbuf);
779
780 inode_lock(file_inode(file));
781
782 p = kbuf;
783 while ((s = strsep(&p, " \t\n"))) {
784 len = strlen(s);
785 if (len == 0)
786 continue;
787 ret = -ENAMETOOLONG;
788 if (len >= AFSNAMEMAX)
789 goto error;
790
791 if (len >= 4 &&
792 s[len - 4] == '@' &&
793 s[len - 3] == 's' &&
794 s[len - 2] == 'y' &&
795 s[len - 1] == 's')
796 /* Protect against recursion */
797 goto invalid;
798
799 if (s[0] == '.' &&
800 (len < 2 || (len == 2 && s[1] == '.')))
801 goto invalid;
802
803 if (memchr(s, '/', len))
804 goto invalid;
805
806 ret = -EFBIG;
807 if (sysnames->nr >= AFS_NR_SYSNAME)
808 goto out;
809
810 if (strcmp(s, afs_init_sysname) == 0) {
811 sub = (char *)afs_init_sysname;
812 } else {
813 ret = -ENOMEM;
814 sub = kmemdup(s, len + 1, GFP_KERNEL);
815 if (!sub)
816 goto out;
817 }
818
819 sysnames->subs[sysnames->nr] = sub;
820 sysnames->nr++;
821 }
822
823 ret = size; /* consume everything, always */
824out:
825 inode_unlock(file_inode(file));
826 kfree(kbuf);
827 return ret;
828
829invalid:
830 ret = -EINVAL;
831error:
832 sysnames->error = ret;
833 goto out;
834}
835
836static int afs_proc_sysname_release(struct inode *inode, struct file *file)
837{
838 struct afs_sysnames *sysnames, *kill = NULL;
839 struct seq_file *m = file->private_data;
840 struct afs_net *net = afs_seq2net(m);
841
842 sysnames = m->private;
843 if (sysnames) {
844 if (!sysnames->error) {
845 kill = sysnames;
846 if (sysnames->nr == 0) {
847 sysnames->subs[0] = sysnames->blank;
848 sysnames->nr++;
849 }
850 write_lock(&net->sysnames_lock);
851 kill = net->sysnames;
852 net->sysnames = sysnames;
853 write_unlock(&net->sysnames_lock);
854 }
855 afs_put_sysnames(kill);
856 }
857
858 return seq_release(inode, file);
859}
860
861static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos)
862 __acquires(&net->sysnames_lock)
863{
864 struct afs_net *net = afs_seq2net(m);
865 struct afs_sysnames *names = net->sysnames;
866
867 read_lock(&net->sysnames_lock);
868
869 if (*pos >= names->nr)
870 return NULL;
871 return (void *)(unsigned long)(*pos + 1);
872}
873
874static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos)
875{
876 struct afs_net *net = afs_seq2net(m);
877 struct afs_sysnames *names = net->sysnames;
878
879 *pos += 1;
880 if (*pos >= names->nr)
881 return NULL;
882 return (void *)(unsigned long)(*pos + 1);
883}
884
885static void afs_proc_sysname_stop(struct seq_file *m, void *v)
886 __releases(&net->sysnames_lock)
887{
888 struct afs_net *net = afs_seq2net(m);
889
890 read_unlock(&net->sysnames_lock);
891}
892
893static int afs_proc_sysname_show(struct seq_file *m, void *v)
894{
895 struct afs_net *net = afs_seq2net(m);
896 struct afs_sysnames *sysnames = net->sysnames;
897 unsigned int i = (unsigned long)v - 1;
898
899 if (i < sysnames->nr)
900 seq_printf(m, "%s\n", sysnames->subs[i]);
901 return 0;
902}
903
904/*
905 * Display general per-net namespace statistics
906 */
907static int afs_proc_stats_show(struct seq_file *m, void *v)
908{
909 struct afs_net *net = afs_seq2net(m);
910
911 seq_puts(m, "kAFS statistics\n");
912
913 seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n",
914 atomic_read(&net->n_lookup),
915 atomic_read(&net->n_reval),
916 atomic_read(&net->n_inval),
917 atomic_read(&net->n_relpg));
918
919 seq_printf(m, "dir-data: rdpg=%u\n",
920 atomic_read(&net->n_read_dir));
921
922 seq_printf(m, "dir-edit: cr=%u rm=%u\n",
923 atomic_read(&net->n_dir_cr),
924 atomic_read(&net->n_dir_rm));
925
926 seq_printf(m, "file-rd : n=%u nb=%lu\n",
927 atomic_read(&net->n_fetches),
928 atomic_long_read(&net->n_fetch_bytes));
929 seq_printf(m, "file-wr : n=%u nb=%lu\n",
930 atomic_read(&net->n_stores),
931 atomic_long_read(&net->n_store_bytes));
932 return 0;
933}
934
935/*
936 * Open "/proc/fs/afs/stats" to allow reading of the stat counters.
937 */
938static int afs_proc_stats_open(struct inode *inode, struct file *file)
939{
940 return single_open(file, afs_proc_stats_show, NULL);
941}
942
943static const struct file_operations afs_proc_stats_fops = {
944 .open = afs_proc_stats_open,
945 .read = seq_read,
946 .llseek = seq_lseek,
947 .release = single_release,
948};
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
20static struct proc_dir_entry *proc_afs;
21
22
23static int afs_proc_cells_open(struct inode *inode, struct file *file);
24static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
25static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
26static void afs_proc_cells_stop(struct seq_file *p, void *v);
27static int afs_proc_cells_show(struct seq_file *m, void *v);
28static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
29 size_t size, loff_t *_pos);
30
31static 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
38static 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
47static int afs_proc_rootcell_open(struct inode *inode, struct file *file);
48static int afs_proc_rootcell_release(struct inode *inode, struct file *file);
49static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
50 size_t size, loff_t *_pos);
51static ssize_t afs_proc_rootcell_write(struct file *file,
52 const char __user *buf,
53 size_t size, loff_t *_pos);
54
55static 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
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 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
80static 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
88static int afs_proc_cell_vlservers_open(struct inode *inode,
89 struct file *file);
90static int afs_proc_cell_vlservers_release(struct inode *inode,
91 struct file *file);
92static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
93static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
94 loff_t *pos);
95static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
96static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
97
98static 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
105static 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
113static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
114static int afs_proc_cell_servers_release(struct inode *inode,
115 struct file *file);
116static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
117static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
118 loff_t *pos);
119static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
120static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
121
122static 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
129static 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 */
140int 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
161error_rootcell:
162 remove_proc_entry("cells", proc_afs);
163error_cells:
164 remove_proc_entry("fs/afs", NULL);
165error_dir:
166 _leave(" = -ENOMEM");
167 return -ENOMEM;
168}
169
170/*
171 * clean up the /proc/fs/afs/ directory
172 */
173void 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 */
183static 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 */
202static 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 */
212static 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 */
220static 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 */
228static 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 */
248static 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
311done:
312 kfree(kbuf);
313 _leave(" = %d", ret);
314 return ret;
315
316inval:
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 */
325static int afs_proc_rootcell_open(struct inode *inode, struct file *file)
326{
327 return 0;
328}
329
330static int afs_proc_rootcell_release(struct inode *inode, struct file *file)
331{
332 return 0;
333}
334
335static 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 */
345static 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
378infault:
379 kfree(kbuf);
380nomem:
381 _leave(" = %d", ret);
382 return ret;
383}
384
385/*
386 * initialise /proc/fs/afs/<cell>/
387 */
388int 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
416error_volumes:
417 remove_proc_entry("vlservers", cell->proc_dir);
418error_vlservers:
419 remove_proc_entry("servers", cell->proc_dir);
420error_servers:
421 remove_proc_entry(cell->name, proc_afs);
422error_dir:
423 _leave(" = -ENOMEM");
424 return -ENOMEM;
425}
426
427/*
428 * remove /proc/fs/afs/<cell>/
429 */
430void 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 */
445static 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 */
468static 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 */
477static 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 */
491static 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 */
503static 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
510static 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 */
523static 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 */
551static 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 */
574static 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 */
584static 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 */
608static 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 */
627static 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 */
637static 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 */
656static 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 */
678static 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 */
688static 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 */
703static 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 */
715static 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 */
726static 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}