xref: /linux/fs/afs/proc.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 /* /proc interface for AFS
2  *
3  * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version
9  * 2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/slab.h>
13 #include <linux/module.h>
14 #include <linux/proc_fs.h>
15 #include <linux/seq_file.h>
16 #include <linux/sched.h>
17 #include <asm/uaccess.h>
18 #include "internal.h"
19 
20 static struct proc_dir_entry *proc_afs;
21 
22 
23 static int afs_proc_cells_open(struct inode *inode, struct file *file);
24 static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
25 static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
26 static void afs_proc_cells_stop(struct seq_file *p, void *v);
27 static int afs_proc_cells_show(struct seq_file *m, void *v);
28 static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
29 				    size_t size, loff_t *_pos);
30 
31 static struct seq_operations afs_proc_cells_ops = {
32 	.start	= afs_proc_cells_start,
33 	.next	= afs_proc_cells_next,
34 	.stop	= afs_proc_cells_stop,
35 	.show	= afs_proc_cells_show,
36 };
37 
38 static const struct file_operations afs_proc_cells_fops = {
39 	.open		= afs_proc_cells_open,
40 	.read		= seq_read,
41 	.write		= afs_proc_cells_write,
42 	.llseek		= seq_lseek,
43 	.release	= seq_release,
44 	.owner		= THIS_MODULE,
45 };
46 
47 static int afs_proc_rootcell_open(struct inode *inode, struct file *file);
48 static int afs_proc_rootcell_release(struct inode *inode, struct file *file);
49 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
50 				      size_t size, loff_t *_pos);
51 static ssize_t afs_proc_rootcell_write(struct file *file,
52 				       const char __user *buf,
53 				       size_t size, loff_t *_pos);
54 
55 static const struct file_operations afs_proc_rootcell_fops = {
56 	.open		= afs_proc_rootcell_open,
57 	.read		= afs_proc_rootcell_read,
58 	.write		= afs_proc_rootcell_write,
59 	.llseek		= no_llseek,
60 	.release	= afs_proc_rootcell_release,
61 	.owner		= THIS_MODULE,
62 };
63 
64 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
65 static int afs_proc_cell_volumes_release(struct inode *inode,
66 					 struct file *file);
67 static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
68 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
69 					loff_t *pos);
70 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
71 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
72 
73 static struct seq_operations afs_proc_cell_volumes_ops = {
74 	.start	= afs_proc_cell_volumes_start,
75 	.next	= afs_proc_cell_volumes_next,
76 	.stop	= afs_proc_cell_volumes_stop,
77 	.show	= afs_proc_cell_volumes_show,
78 };
79 
80 static const struct file_operations afs_proc_cell_volumes_fops = {
81 	.open		= afs_proc_cell_volumes_open,
82 	.read		= seq_read,
83 	.llseek		= seq_lseek,
84 	.release	= afs_proc_cell_volumes_release,
85 	.owner		= THIS_MODULE,
86 };
87 
88 static int afs_proc_cell_vlservers_open(struct inode *inode,
89 					struct file *file);
90 static int afs_proc_cell_vlservers_release(struct inode *inode,
91 					   struct file *file);
92 static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
93 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
94 					  loff_t *pos);
95 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
96 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
97 
98 static struct seq_operations afs_proc_cell_vlservers_ops = {
99 	.start	= afs_proc_cell_vlservers_start,
100 	.next	= afs_proc_cell_vlservers_next,
101 	.stop	= afs_proc_cell_vlservers_stop,
102 	.show	= afs_proc_cell_vlservers_show,
103 };
104 
105 static const struct file_operations afs_proc_cell_vlservers_fops = {
106 	.open		= afs_proc_cell_vlservers_open,
107 	.read		= seq_read,
108 	.llseek		= seq_lseek,
109 	.release	= afs_proc_cell_vlservers_release,
110 	.owner		= THIS_MODULE,
111 };
112 
113 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
114 static int afs_proc_cell_servers_release(struct inode *inode,
115 					 struct file *file);
116 static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
117 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
118 					loff_t *pos);
119 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
120 static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
121 
122 static struct seq_operations afs_proc_cell_servers_ops = {
123 	.start	= afs_proc_cell_servers_start,
124 	.next	= afs_proc_cell_servers_next,
125 	.stop	= afs_proc_cell_servers_stop,
126 	.show	= afs_proc_cell_servers_show,
127 };
128 
129 static const struct file_operations afs_proc_cell_servers_fops = {
130 	.open		= afs_proc_cell_servers_open,
131 	.read		= seq_read,
132 	.llseek		= seq_lseek,
133 	.release	= afs_proc_cell_servers_release,
134 	.owner		= THIS_MODULE,
135 };
136 
137 /*
138  * initialise the /proc/fs/afs/ directory
139  */
140 int afs_proc_init(void)
141 {
142 	struct proc_dir_entry *p;
143 
144 	_enter("");
145 
146 	proc_afs = proc_mkdir("fs/afs", NULL);
147 	if (!proc_afs)
148 		goto error_dir;
149 	proc_afs->owner = THIS_MODULE;
150 
151 	p = proc_create("cells", 0, proc_afs, &afs_proc_cells_fops);
152 	if (!p)
153 		goto error_cells;
154 
155 	p = proc_create("rootcell", 0, proc_afs, &afs_proc_rootcell_fops);
156 	if (!p)
157 		goto error_rootcell;
158 
159 	_leave(" = 0");
160 	return 0;
161 
162 error_rootcell:
163  	remove_proc_entry("cells", proc_afs);
164 error_cells:
165 	remove_proc_entry("fs/afs", NULL);
166 error_dir:
167 	_leave(" = -ENOMEM");
168 	return -ENOMEM;
169 }
170 
171 /*
172  * clean up the /proc/fs/afs/ directory
173  */
174 void afs_proc_cleanup(void)
175 {
176 	remove_proc_entry("rootcell", proc_afs);
177 	remove_proc_entry("cells", proc_afs);
178 	remove_proc_entry("fs/afs", NULL);
179 }
180 
181 /*
182  * open "/proc/fs/afs/cells" which provides a summary of extant cells
183  */
184 static int afs_proc_cells_open(struct inode *inode, struct file *file)
185 {
186 	struct seq_file *m;
187 	int ret;
188 
189 	ret = seq_open(file, &afs_proc_cells_ops);
190 	if (ret < 0)
191 		return ret;
192 
193 	m = file->private_data;
194 	m->private = PDE(inode)->data;
195 
196 	return 0;
197 }
198 
199 /*
200  * set up the iterator to start reading from the cells list and return the
201  * first item
202  */
203 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
204 {
205 	/* lock the list against modification */
206 	down_read(&afs_proc_cells_sem);
207 	return seq_list_start_head(&afs_proc_cells, *_pos);
208 }
209 
210 /*
211  * move to next cell in cells list
212  */
213 static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
214 {
215 	return seq_list_next(v, &afs_proc_cells, pos);
216 }
217 
218 /*
219  * clean up after reading from the cells list
220  */
221 static void afs_proc_cells_stop(struct seq_file *p, void *v)
222 {
223 	up_read(&afs_proc_cells_sem);
224 }
225 
226 /*
227  * display a header line followed by a load of cell lines
228  */
229 static int afs_proc_cells_show(struct seq_file *m, void *v)
230 {
231 	struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
232 
233 	if (v == &afs_proc_cells) {
234 		/* display header on line 1 */
235 		seq_puts(m, "USE NAME\n");
236 		return 0;
237 	}
238 
239 	/* display one cell per line on subsequent lines */
240 	seq_printf(m, "%3d %s\n",
241 		   atomic_read(&cell->usage), cell->name);
242 	return 0;
243 }
244 
245 /*
246  * handle writes to /proc/fs/afs/cells
247  * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
248  */
249 static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
250 				    size_t size, loff_t *_pos)
251 {
252 	char *kbuf, *name, *args;
253 	int ret;
254 
255 	/* start by dragging the command into memory */
256 	if (size <= 1 || size >= PAGE_SIZE)
257 		return -EINVAL;
258 
259 	kbuf = kmalloc(size + 1, GFP_KERNEL);
260 	if (!kbuf)
261 		return -ENOMEM;
262 
263 	ret = -EFAULT;
264 	if (copy_from_user(kbuf, buf, size) != 0)
265 		goto done;
266 	kbuf[size] = 0;
267 
268 	/* trim to first NL */
269 	name = memchr(kbuf, '\n', size);
270 	if (name)
271 		*name = 0;
272 
273 	/* split into command, name and argslist */
274 	name = strchr(kbuf, ' ');
275 	if (!name)
276 		goto inval;
277 	do {
278 		*name++ = 0;
279 	} while(*name == ' ');
280 	if (!*name)
281 		goto inval;
282 
283 	args = strchr(name, ' ');
284 	if (!args)
285 		goto inval;
286 	do {
287 		*args++ = 0;
288 	} while(*args == ' ');
289 	if (!*args)
290 		goto inval;
291 
292 	/* determine command to perform */
293 	_debug("cmd=%s name=%s args=%s", kbuf, name, args);
294 
295 	if (strcmp(kbuf, "add") == 0) {
296 		struct afs_cell *cell;
297 
298 		cell = afs_cell_create(name, args);
299 		if (IS_ERR(cell)) {
300 			ret = PTR_ERR(cell);
301 			goto done;
302 		}
303 
304 		afs_put_cell(cell);
305 		printk("kAFS: Added new cell '%s'\n", name);
306 	} else {
307 		goto inval;
308 	}
309 
310 	ret = size;
311 
312 done:
313 	kfree(kbuf);
314 	_leave(" = %d", ret);
315 	return ret;
316 
317 inval:
318 	ret = -EINVAL;
319 	printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
320 	goto done;
321 }
322 
323 /*
324  * Stubs for /proc/fs/afs/rootcell
325  */
326 static int afs_proc_rootcell_open(struct inode *inode, struct file *file)
327 {
328 	return 0;
329 }
330 
331 static int afs_proc_rootcell_release(struct inode *inode, struct file *file)
332 {
333 	return 0;
334 }
335 
336 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
337 				      size_t size, loff_t *_pos)
338 {
339 	return 0;
340 }
341 
342 /*
343  * handle writes to /proc/fs/afs/rootcell
344  * - to initialize rootcell: echo "cell.name:192.168.231.14"
345  */
346 static ssize_t afs_proc_rootcell_write(struct file *file,
347 				       const char __user *buf,
348 				       size_t size, loff_t *_pos)
349 {
350 	char *kbuf, *s;
351 	int ret;
352 
353 	/* start by dragging the command into memory */
354 	if (size <= 1 || size >= PAGE_SIZE)
355 		return -EINVAL;
356 
357 	ret = -ENOMEM;
358 	kbuf = kmalloc(size + 1, GFP_KERNEL);
359 	if (!kbuf)
360 		goto nomem;
361 
362 	ret = -EFAULT;
363 	if (copy_from_user(kbuf, buf, size) != 0)
364 		goto infault;
365 	kbuf[size] = 0;
366 
367 	/* trim to first NL */
368 	s = memchr(kbuf, '\n', size);
369 	if (s)
370 		*s = 0;
371 
372 	/* determine command to perform */
373 	_debug("rootcell=%s", kbuf);
374 
375 	ret = afs_cell_init(kbuf);
376 	if (ret >= 0)
377 		ret = size;	/* consume everything, always */
378 
379 infault:
380 	kfree(kbuf);
381 nomem:
382 	_leave(" = %d", ret);
383 	return ret;
384 }
385 
386 /*
387  * initialise /proc/fs/afs/<cell>/
388  */
389 int afs_proc_cell_setup(struct afs_cell *cell)
390 {
391 	struct proc_dir_entry *p;
392 
393 	_enter("%p{%s}", cell, cell->name);
394 
395 	cell->proc_dir = proc_mkdir(cell->name, proc_afs);
396 	if (!cell->proc_dir)
397 		goto error_dir;
398 
399 	p = proc_create_data("servers", 0, cell->proc_dir,
400 			     &afs_proc_cell_servers_fops, cell);
401 	if (!p)
402 		goto error_servers;
403 
404 	p = proc_create_data("vlservers", 0, cell->proc_dir,
405 			     &afs_proc_cell_vlservers_fops, cell);
406 	if (!p)
407 		goto error_vlservers;
408 
409 	p = proc_create_data("volumes", 0, cell->proc_dir,
410 			     &afs_proc_cell_volumes_fops, cell);
411 	if (!p)
412 		goto error_volumes;
413 
414 	_leave(" = 0");
415 	return 0;
416 
417 error_volumes:
418 	remove_proc_entry("vlservers", cell->proc_dir);
419 error_vlservers:
420 	remove_proc_entry("servers", cell->proc_dir);
421 error_servers:
422 	remove_proc_entry(cell->name, proc_afs);
423 error_dir:
424 	_leave(" = -ENOMEM");
425 	return -ENOMEM;
426 }
427 
428 /*
429  * remove /proc/fs/afs/<cell>/
430  */
431 void afs_proc_cell_remove(struct afs_cell *cell)
432 {
433 	_enter("");
434 
435 	remove_proc_entry("volumes", cell->proc_dir);
436 	remove_proc_entry("vlservers", cell->proc_dir);
437 	remove_proc_entry("servers", cell->proc_dir);
438 	remove_proc_entry(cell->name, proc_afs);
439 
440 	_leave("");
441 }
442 
443 /*
444  * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
445  */
446 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
447 {
448 	struct afs_cell *cell;
449 	struct seq_file *m;
450 	int ret;
451 
452 	cell = PDE(inode)->data;
453 	if (!cell)
454 		return -ENOENT;
455 
456 	ret = seq_open(file, &afs_proc_cell_volumes_ops);
457 	if (ret < 0)
458 		return ret;
459 
460 	m = file->private_data;
461 	m->private = cell;
462 
463 	return 0;
464 }
465 
466 /*
467  * close the file and release the ref to the cell
468  */
469 static int afs_proc_cell_volumes_release(struct inode *inode, struct file *file)
470 {
471 	return seq_release(inode, file);
472 }
473 
474 /*
475  * set up the iterator to start reading from the cells list and return the
476  * first item
477  */
478 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
479 {
480 	struct afs_cell *cell = m->private;
481 
482 	_enter("cell=%p pos=%Ld", cell, *_pos);
483 
484 	/* lock the list against modification */
485 	down_read(&cell->vl_sem);
486 	return seq_list_start_head(&cell->vl_list, *_pos);
487 }
488 
489 /*
490  * move to next cell in cells list
491  */
492 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
493 					loff_t *_pos)
494 {
495 	struct afs_cell *cell = p->private;
496 
497 	_enter("cell=%p pos=%Ld", cell, *_pos);
498 	return seq_list_next(v, &cell->vl_list, _pos);
499 }
500 
501 /*
502  * clean up after reading from the cells list
503  */
504 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
505 {
506 	struct afs_cell *cell = p->private;
507 
508 	up_read(&cell->vl_sem);
509 }
510 
511 static const char afs_vlocation_states[][4] = {
512 	[AFS_VL_NEW]			= "New",
513 	[AFS_VL_CREATING]		= "Crt",
514 	[AFS_VL_VALID]			= "Val",
515 	[AFS_VL_NO_VOLUME]		= "NoV",
516 	[AFS_VL_UPDATING]		= "Upd",
517 	[AFS_VL_VOLUME_DELETED]		= "Del",
518 	[AFS_VL_UNCERTAIN]		= "Unc",
519 };
520 
521 /*
522  * display a header line followed by a load of volume lines
523  */
524 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
525 {
526 	struct afs_cell *cell = m->private;
527 	struct afs_vlocation *vlocation =
528 		list_entry(v, struct afs_vlocation, link);
529 
530 	/* display header on line 1 */
531 	if (v == &cell->vl_list) {
532 		seq_puts(m, "USE STT VLID[0]  VLID[1]  VLID[2]  NAME\n");
533 		return 0;
534 	}
535 
536 	/* display one cell per line on subsequent lines */
537 	seq_printf(m, "%3d %s %08x %08x %08x %s\n",
538 		   atomic_read(&vlocation->usage),
539 		   afs_vlocation_states[vlocation->state],
540 		   vlocation->vldb.vid[0],
541 		   vlocation->vldb.vid[1],
542 		   vlocation->vldb.vid[2],
543 		   vlocation->vldb.name);
544 
545 	return 0;
546 }
547 
548 /*
549  * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
550  * location server
551  */
552 static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
553 {
554 	struct afs_cell *cell;
555 	struct seq_file *m;
556 	int ret;
557 
558 	cell = PDE(inode)->data;
559 	if (!cell)
560 		return -ENOENT;
561 
562 	ret = seq_open(file, &afs_proc_cell_vlservers_ops);
563 	if (ret<0)
564 		return ret;
565 
566 	m = file->private_data;
567 	m->private = cell;
568 
569 	return 0;
570 }
571 
572 /*
573  * close the file and release the ref to the cell
574  */
575 static int afs_proc_cell_vlservers_release(struct inode *inode,
576 					   struct file *file)
577 {
578 	return seq_release(inode, file);
579 }
580 
581 /*
582  * set up the iterator to start reading from the cells list and return the
583  * first item
584  */
585 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
586 {
587 	struct afs_cell *cell = m->private;
588 	loff_t pos = *_pos;
589 
590 	_enter("cell=%p pos=%Ld", cell, *_pos);
591 
592 	/* lock the list against modification */
593 	down_read(&cell->vl_sem);
594 
595 	/* allow for the header line */
596 	if (!pos)
597 		return (void *) 1;
598 	pos--;
599 
600 	if (pos >= cell->vl_naddrs)
601 		return NULL;
602 
603 	return &cell->vl_addrs[pos];
604 }
605 
606 /*
607  * move to next cell in cells list
608  */
609 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
610 					  loff_t *_pos)
611 {
612 	struct afs_cell *cell = p->private;
613 	loff_t pos;
614 
615 	_enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
616 
617 	pos = *_pos;
618 	(*_pos)++;
619 	if (pos >= cell->vl_naddrs)
620 		return NULL;
621 
622 	return &cell->vl_addrs[pos];
623 }
624 
625 /*
626  * clean up after reading from the cells list
627  */
628 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
629 {
630 	struct afs_cell *cell = p->private;
631 
632 	up_read(&cell->vl_sem);
633 }
634 
635 /*
636  * display a header line followed by a load of volume lines
637  */
638 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
639 {
640 	struct in_addr *addr = v;
641 
642 	/* display header on line 1 */
643 	if (v == (struct in_addr *) 1) {
644 		seq_puts(m, "ADDRESS\n");
645 		return 0;
646 	}
647 
648 	/* display one cell per line on subsequent lines */
649 	seq_printf(m, "%u.%u.%u.%u\n", NIPQUAD(addr->s_addr));
650 	return 0;
651 }
652 
653 /*
654  * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
655  * servers
656  */
657 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
658 {
659 	struct afs_cell *cell;
660 	struct seq_file *m;
661 	int ret;
662 
663 	cell = PDE(inode)->data;
664 	if (!cell)
665 		return -ENOENT;
666 
667 	ret = seq_open(file, &afs_proc_cell_servers_ops);
668 	if (ret < 0)
669 		return ret;
670 
671 	m = file->private_data;
672 	m->private = cell;
673 	return 0;
674 }
675 
676 /*
677  * close the file and release the ref to the cell
678  */
679 static int afs_proc_cell_servers_release(struct inode *inode,
680 					 struct file *file)
681 {
682 	return seq_release(inode, file);
683 }
684 
685 /*
686  * set up the iterator to start reading from the cells list and return the
687  * first item
688  */
689 static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
690 	__acquires(m->private->servers_lock)
691 {
692 	struct afs_cell *cell = m->private;
693 
694 	_enter("cell=%p pos=%Ld", cell, *_pos);
695 
696 	/* lock the list against modification */
697 	read_lock(&cell->servers_lock);
698 	return seq_list_start_head(&cell->servers, *_pos);
699 }
700 
701 /*
702  * move to next cell in cells list
703  */
704 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
705 					loff_t *_pos)
706 {
707 	struct afs_cell *cell = p->private;
708 
709 	_enter("cell=%p pos=%Ld", cell, *_pos);
710 	return seq_list_next(v, &cell->servers, _pos);
711 }
712 
713 /*
714  * clean up after reading from the cells list
715  */
716 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
717 	__releases(p->private->servers_lock)
718 {
719 	struct afs_cell *cell = p->private;
720 
721 	read_unlock(&cell->servers_lock);
722 }
723 
724 /*
725  * display a header line followed by a load of volume lines
726  */
727 static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
728 {
729 	struct afs_cell *cell = m->private;
730 	struct afs_server *server = list_entry(v, struct afs_server, link);
731 	char ipaddr[20];
732 
733 	/* display header on line 1 */
734 	if (v == &cell->servers) {
735 		seq_puts(m, "USE ADDR            STATE\n");
736 		return 0;
737 	}
738 
739 	/* display one cell per line on subsequent lines */
740 	sprintf(ipaddr, "%u.%u.%u.%u", NIPQUAD(server->addr));
741 	seq_printf(m, "%3d %-15.15s %5d\n",
742 		   atomic_read(&server->usage), ipaddr, server->fs_state);
743 
744 	return 0;
745 }
746