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v4.17
  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};
v3.15
  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};
 45
 46static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
 47				      size_t size, loff_t *_pos);
 48static ssize_t afs_proc_rootcell_write(struct file *file,
 49				       const char __user *buf,
 50				       size_t size, loff_t *_pos);
 51
 52static const struct file_operations afs_proc_rootcell_fops = {
 53	.read		= afs_proc_rootcell_read,
 54	.write		= afs_proc_rootcell_write,
 55	.llseek		= no_llseek,
 56};
 57
 58static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
 59static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
 60static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
 61					loff_t *pos);
 62static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
 63static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
 64
 65static const struct seq_operations afs_proc_cell_volumes_ops = {
 66	.start	= afs_proc_cell_volumes_start,
 67	.next	= afs_proc_cell_volumes_next,
 68	.stop	= afs_proc_cell_volumes_stop,
 69	.show	= afs_proc_cell_volumes_show,
 70};
 71
 72static const struct file_operations afs_proc_cell_volumes_fops = {
 73	.open		= afs_proc_cell_volumes_open,
 74	.read		= seq_read,
 75	.llseek		= seq_lseek,
 76	.release	= seq_release,
 77};
 78
 79static int afs_proc_cell_vlservers_open(struct inode *inode,
 80					struct file *file);
 81static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
 82static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
 83					  loff_t *pos);
 84static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
 85static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
 86
 87static const struct seq_operations afs_proc_cell_vlservers_ops = {
 88	.start	= afs_proc_cell_vlservers_start,
 89	.next	= afs_proc_cell_vlservers_next,
 90	.stop	= afs_proc_cell_vlservers_stop,
 91	.show	= afs_proc_cell_vlservers_show,
 92};
 93
 94static const struct file_operations afs_proc_cell_vlservers_fops = {
 95	.open		= afs_proc_cell_vlservers_open,
 96	.read		= seq_read,
 97	.llseek		= seq_lseek,
 98	.release	= seq_release,
 99};
100
101static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
102static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
103static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
104					loff_t *pos);
105static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
106static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
107
108static const struct seq_operations afs_proc_cell_servers_ops = {
109	.start	= afs_proc_cell_servers_start,
110	.next	= afs_proc_cell_servers_next,
111	.stop	= afs_proc_cell_servers_stop,
112	.show	= afs_proc_cell_servers_show,
113};
114
115static const struct file_operations afs_proc_cell_servers_fops = {
116	.open		= afs_proc_cell_servers_open,
117	.read		= seq_read,
118	.llseek		= seq_lseek,
119	.release	= seq_release,
120};
121
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
122/*
123 * initialise the /proc/fs/afs/ directory
124 */
125int afs_proc_init(void)
126{
127	_enter("");
128
129	proc_afs = proc_mkdir("fs/afs", NULL);
130	if (!proc_afs)
131		goto error_dir;
132
133	if (!proc_create("cells", 0644, proc_afs, &afs_proc_cells_fops) ||
134	    !proc_create("rootcell", 0644, proc_afs, &afs_proc_rootcell_fops))
 
 
 
135		goto error_tree;
136
137	_leave(" = 0");
138	return 0;
139
140error_tree:
141	remove_proc_subtree("fs/afs", NULL);
142error_dir:
143	_leave(" = -ENOMEM");
144	return -ENOMEM;
145}
146
147/*
148 * clean up the /proc/fs/afs/ directory
149 */
150void afs_proc_cleanup(void)
151{
152	remove_proc_subtree("fs/afs", NULL);
 
153}
154
155/*
156 * open "/proc/fs/afs/cells" which provides a summary of extant cells
157 */
158static int afs_proc_cells_open(struct inode *inode, struct file *file)
159{
160	struct seq_file *m;
161	int ret;
162
163	ret = seq_open(file, &afs_proc_cells_ops);
164	if (ret < 0)
165		return ret;
166
167	m = file->private_data;
168	m->private = PDE_DATA(inode);
169
170	return 0;
171}
172
173/*
174 * set up the iterator to start reading from the cells list and return the
175 * first item
176 */
177static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
 
178{
179	/* lock the list against modification */
180	down_read(&afs_proc_cells_sem);
181	return seq_list_start_head(&afs_proc_cells, *_pos);
 
182}
183
184/*
185 * move to next cell in cells list
186 */
187static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
188{
189	return seq_list_next(v, &afs_proc_cells, pos);
 
 
190}
191
192/*
193 * clean up after reading from the cells list
194 */
195static void afs_proc_cells_stop(struct seq_file *p, void *v)
 
196{
197	up_read(&afs_proc_cells_sem);
198}
199
200/*
201 * display a header line followed by a load of cell lines
202 */
203static int afs_proc_cells_show(struct seq_file *m, void *v)
204{
205	struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
 
206
207	if (v == &afs_proc_cells) {
208		/* display header on line 1 */
209		seq_puts(m, "USE NAME\n");
210		return 0;
211	}
212
213	/* display one cell per line on subsequent lines */
214	seq_printf(m, "%3d %s\n",
215		   atomic_read(&cell->usage), cell->name);
216	return 0;
217}
218
219/*
220 * handle writes to /proc/fs/afs/cells
221 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
222 */
223static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
224				    size_t size, loff_t *_pos)
225{
 
226	char *kbuf, *name, *args;
227	int ret;
228
229	/* start by dragging the command into memory */
230	if (size <= 1 || size >= PAGE_SIZE)
231		return -EINVAL;
232
233	kbuf = kmalloc(size + 1, GFP_KERNEL);
234	if (!kbuf)
235		return -ENOMEM;
236
237	ret = -EFAULT;
238	if (copy_from_user(kbuf, buf, size) != 0)
239		goto done;
240	kbuf[size] = 0;
241
242	/* trim to first NL */
243	name = memchr(kbuf, '\n', size);
244	if (name)
245		*name = 0;
246
247	/* split into command, name and argslist */
248	name = strchr(kbuf, ' ');
249	if (!name)
250		goto inval;
251	do {
252		*name++ = 0;
253	} while(*name == ' ');
254	if (!*name)
255		goto inval;
256
257	args = strchr(name, ' ');
258	if (!args)
259		goto inval;
260	do {
261		*args++ = 0;
262	} while(*args == ' ');
263	if (!*args)
264		goto inval;
265
266	/* determine command to perform */
267	_debug("cmd=%s name=%s args=%s", kbuf, name, args);
268
269	if (strcmp(kbuf, "add") == 0) {
270		struct afs_cell *cell;
271
272		cell = afs_cell_create(name, strlen(name), args, false);
273		if (IS_ERR(cell)) {
274			ret = PTR_ERR(cell);
275			goto done;
276		}
277
278		afs_put_cell(cell);
 
279		printk("kAFS: Added new cell '%s'\n", name);
280	} else {
281		goto inval;
282	}
283
284	ret = size;
285
286done:
287	kfree(kbuf);
288	_leave(" = %d", ret);
289	return ret;
290
291inval:
292	ret = -EINVAL;
293	printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
294	goto done;
295}
296
297static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
298				      size_t size, loff_t *_pos)
299{
300	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
301}
302
303/*
304 * handle writes to /proc/fs/afs/rootcell
305 * - to initialize rootcell: echo "cell.name:192.168.231.14"
306 */
307static ssize_t afs_proc_rootcell_write(struct file *file,
308				       const char __user *buf,
309				       size_t size, loff_t *_pos)
310{
 
311	char *kbuf, *s;
312	int ret;
313
314	/* start by dragging the command into memory */
315	if (size <= 1 || size >= PAGE_SIZE)
316		return -EINVAL;
317
318	ret = -ENOMEM;
319	kbuf = kmalloc(size + 1, GFP_KERNEL);
320	if (!kbuf)
321		goto nomem;
322
323	ret = -EFAULT;
324	if (copy_from_user(kbuf, buf, size) != 0)
325		goto infault;
326	kbuf[size] = 0;
327
328	/* trim to first NL */
329	s = memchr(kbuf, '\n', size);
330	if (s)
331		*s = 0;
332
333	/* determine command to perform */
334	_debug("rootcell=%s", kbuf);
335
336	ret = afs_cell_init(kbuf);
337	if (ret >= 0)
338		ret = size;	/* consume everything, always */
339
340infault:
341	kfree(kbuf);
342nomem:
343	_leave(" = %d", ret);
344	return ret;
345}
346
347/*
348 * initialise /proc/fs/afs/<cell>/
349 */
350int afs_proc_cell_setup(struct afs_cell *cell)
351{
352	struct proc_dir_entry *dir;
353
354	_enter("%p{%s}", cell, cell->name);
355
356	dir = proc_mkdir(cell->name, proc_afs);
357	if (!dir)
358		goto error_dir;
359
360	if (!proc_create_data("servers", 0, dir,
361			     &afs_proc_cell_servers_fops, cell) ||
362	    !proc_create_data("vlservers", 0, dir,
363			     &afs_proc_cell_vlservers_fops, cell) ||
364	    !proc_create_data("volumes", 0, dir,
365			     &afs_proc_cell_volumes_fops, cell))
366		goto error_tree;
367
368	_leave(" = 0");
369	return 0;
370
371error_tree:
372	remove_proc_subtree(cell->name, proc_afs);
373error_dir:
374	_leave(" = -ENOMEM");
375	return -ENOMEM;
376}
377
378/*
379 * remove /proc/fs/afs/<cell>/
380 */
381void afs_proc_cell_remove(struct afs_cell *cell)
382{
383	_enter("");
384
385	remove_proc_subtree(cell->name, proc_afs);
386
387	_leave("");
388}
389
390/*
391 * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
392 */
393static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
394{
395	struct afs_cell *cell;
396	struct seq_file *m;
397	int ret;
398
399	cell = PDE_DATA(inode);
400	if (!cell)
401		return -ENOENT;
402
403	ret = seq_open(file, &afs_proc_cell_volumes_ops);
404	if (ret < 0)
405		return ret;
406
407	m = file->private_data;
408	m->private = cell;
409
410	return 0;
411}
412
413/*
414 * set up the iterator to start reading from the cells list and return the
415 * first item
416 */
417static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
 
418{
419	struct afs_cell *cell = m->private;
420
421	_enter("cell=%p pos=%Ld", cell, *_pos);
422
423	/* lock the list against modification */
424	down_read(&cell->vl_sem);
425	return seq_list_start_head(&cell->vl_list, *_pos);
426}
427
428/*
429 * move to next cell in cells list
430 */
431static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
432					loff_t *_pos)
433{
434	struct afs_cell *cell = p->private;
435
436	_enter("cell=%p pos=%Ld", cell, *_pos);
437	return seq_list_next(v, &cell->vl_list, _pos);
438}
439
440/*
441 * clean up after reading from the cells list
442 */
443static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
 
444{
445	struct afs_cell *cell = p->private;
446
447	up_read(&cell->vl_sem);
448}
449
450static const char afs_vlocation_states[][4] = {
451	[AFS_VL_NEW]			= "New",
452	[AFS_VL_CREATING]		= "Crt",
453	[AFS_VL_VALID]			= "Val",
454	[AFS_VL_NO_VOLUME]		= "NoV",
455	[AFS_VL_UPDATING]		= "Upd",
456	[AFS_VL_VOLUME_DELETED]		= "Del",
457	[AFS_VL_UNCERTAIN]		= "Unc",
458};
459
460/*
461 * display a header line followed by a load of volume lines
462 */
463static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
464{
465	struct afs_cell *cell = m->private;
466	struct afs_vlocation *vlocation =
467		list_entry(v, struct afs_vlocation, link);
468
469	/* display header on line 1 */
470	if (v == &cell->vl_list) {
471		seq_puts(m, "USE STT VLID[0]  VLID[1]  VLID[2]  NAME\n");
472		return 0;
473	}
474
475	/* display one cell per line on subsequent lines */
476	seq_printf(m, "%3d %s %08x %08x %08x %s\n",
477		   atomic_read(&vlocation->usage),
478		   afs_vlocation_states[vlocation->state],
479		   vlocation->vldb.vid[0],
480		   vlocation->vldb.vid[1],
481		   vlocation->vldb.vid[2],
482		   vlocation->vldb.name);
483
484	return 0;
485}
486
487/*
488 * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
489 * location server
490 */
491static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
492{
493	struct afs_cell *cell;
494	struct seq_file *m;
495	int ret;
496
497	cell = PDE_DATA(inode);
498	if (!cell)
499		return -ENOENT;
500
501	ret = seq_open(file, &afs_proc_cell_vlservers_ops);
502	if (ret<0)
503		return ret;
504
505	m = file->private_data;
506	m->private = cell;
507
508	return 0;
509}
510
511/*
512 * set up the iterator to start reading from the cells list and return the
513 * first item
514 */
515static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
 
516{
 
517	struct afs_cell *cell = m->private;
518	loff_t pos = *_pos;
519
520	_enter("cell=%p pos=%Ld", cell, *_pos);
521
522	/* lock the list against modification */
523	down_read(&cell->vl_sem);
524
525	/* allow for the header line */
526	if (!pos)
527		return (void *) 1;
528	pos--;
529
530	if (pos >= cell->vl_naddrs)
531		return NULL;
532
533	return &cell->vl_addrs[pos];
534}
535
536/*
537 * move to next cell in cells list
538 */
539static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
540					  loff_t *_pos)
541{
 
542	struct afs_cell *cell = p->private;
543	loff_t pos;
544
545	_enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
546
547	pos = *_pos;
548	(*_pos)++;
549	if (pos >= cell->vl_naddrs)
550		return NULL;
551
552	return &cell->vl_addrs[pos];
553}
554
555/*
556 * clean up after reading from the cells list
557 */
558static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
 
559{
560	struct afs_cell *cell = p->private;
561
562	up_read(&cell->vl_sem);
563}
564
565/*
566 * display a header line followed by a load of volume lines
567 */
568static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
569{
570	struct in_addr *addr = v;
571
572	/* display header on line 1 */
573	if (v == (struct in_addr *) 1) {
574		seq_puts(m, "ADDRESS\n");
575		return 0;
576	}
577
578	/* display one cell per line on subsequent lines */
579	seq_printf(m, "%pI4\n", &addr->s_addr);
580	return 0;
581}
582
583/*
584 * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
585 * servers
586 */
587static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
588{
589	struct afs_cell *cell;
590	struct seq_file *m;
591	int ret;
592
593	cell = PDE_DATA(inode);
594	if (!cell)
595		return -ENOENT;
 
 
 
 
 
596
597	ret = seq_open(file, &afs_proc_cell_servers_ops);
598	if (ret < 0)
599		return ret;
600
601	m = file->private_data;
602	m->private = cell;
603	return 0;
604}
605
606/*
607 * set up the iterator to start reading from the cells list and return the
608 * first item
609 */
610static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
611	__acquires(m->private->servers_lock)
612{
613	struct afs_cell *cell = m->private;
614
615	_enter("cell=%p pos=%Ld", cell, *_pos);
 
616
617	/* lock the list against modification */
618	read_lock(&cell->servers_lock);
619	return seq_list_start_head(&cell->servers, *_pos);
 
 
 
 
620}
621
622/*
623 * move to next cell in cells list
624 */
625static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
626					loff_t *_pos)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
627{
628	struct afs_cell *cell = p->private;
629
630	_enter("cell=%p pos=%Ld", cell, *_pos);
631	return seq_list_next(v, &cell->servers, _pos);
 
 
 
 
632}
633
634/*
635 * clean up after reading from the cells list
 
 
636 */
637static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
638	__releases(p->private->servers_lock)
639{
640	struct afs_cell *cell = p->private;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
641
642	read_unlock(&cell->servers_lock);
643}
644
645/*
646 * display a header line followed by a load of volume lines
647 */
648static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
 
 
649{
650	struct afs_cell *cell = m->private;
651	struct afs_server *server = list_entry(v, struct afs_server, link);
652	char ipaddr[20];
 
 
 
 
 
 
 
653
654	/* display header on line 1 */
655	if (v == &cell->servers) {
656		seq_puts(m, "USE ADDR            STATE\n");
 
 
657		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
658	}
659
660	/* display one cell per line on subsequent lines */
661	sprintf(ipaddr, "%pI4", &server->addr);
662	seq_printf(m, "%3d %-15.15s %5d\n",
663		   atomic_read(&server->usage), ipaddr, server->fs_state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
664
 
 
 
 
 
 
665	return 0;
666}