xref: /openbmc/linux/fs/afs/proc.c (revision 4beec1d7) 
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 
20 static struct proc_dir_entry *proc_afs;
21 
22 
23 static int afs_proc_cells_open(struct inode *inode, struct file *file);
24 static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
25 static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
26 static void afs_proc_cells_stop(struct seq_file *p, void *v);
27 static int afs_proc_cells_show(struct seq_file *m, void *v);
28 static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
29 				    size_t size, loff_t *_pos);
30 
31 static const struct seq_operations afs_proc_cells_ops = {
32 	.start	= afs_proc_cells_start,
33 	.next	= afs_proc_cells_next,
34 	.stop	= afs_proc_cells_stop,
35 	.show	= afs_proc_cells_show,
36 };
37 
38 static const struct file_operations afs_proc_cells_fops = {
39 	.open		= afs_proc_cells_open,
40 	.read		= seq_read,
41 	.write		= afs_proc_cells_write,
42 	.llseek		= seq_lseek,
43 	.release	= seq_release,
44 };
45 
46 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
47 				      size_t size, loff_t *_pos);
48 static ssize_t afs_proc_rootcell_write(struct file *file,
49 				       const char __user *buf,
50 				       size_t size, loff_t *_pos);
51 
52 static 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 
58 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
59 static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
60 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
61 					loff_t *pos);
62 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
63 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
64 
65 static 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 
72 static 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 
79 static int afs_proc_cell_vlservers_open(struct inode *inode,
80 					struct file *file);
81 static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
82 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
83 					  loff_t *pos);
84 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
85 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
86 
87 static 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 
94 static 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 
101 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
102 static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
103 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
104 					loff_t *pos);
105 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
106 static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
107 
108 static 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 
115 static 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  */
125 int 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 
140 error_tree:
141 	remove_proc_subtree("fs/afs", NULL);
142 error_dir:
143 	_leave(" = -ENOMEM");
144 	return -ENOMEM;
145 }
146 
147 /*
148  * clean up the /proc/fs/afs/ directory
149  */
150 void 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  */
158 static 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  */
177 static 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  */
187 static 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  */
195 static 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  */
203 static 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  */
223 static 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 = memdup_user_nul(buf, size);
234 	if (IS_ERR(kbuf))
235 		return PTR_ERR(kbuf);
236 
237 	/* trim to first NL */
238 	name = memchr(kbuf, '\n', size);
239 	if (name)
240 		*name = 0;
241 
242 	/* split into command, name and argslist */
243 	name = strchr(kbuf, ' ');
244 	if (!name)
245 		goto inval;
246 	do {
247 		*name++ = 0;
248 	} while(*name == ' ');
249 	if (!*name)
250 		goto inval;
251 
252 	args = strchr(name, ' ');
253 	if (!args)
254 		goto inval;
255 	do {
256 		*args++ = 0;
257 	} while(*args == ' ');
258 	if (!*args)
259 		goto inval;
260 
261 	/* determine command to perform */
262 	_debug("cmd=%s name=%s args=%s", kbuf, name, args);
263 
264 	if (strcmp(kbuf, "add") == 0) {
265 		struct afs_cell *cell;
266 
267 		cell = afs_cell_create(name, strlen(name), args, false);
268 		if (IS_ERR(cell)) {
269 			ret = PTR_ERR(cell);
270 			goto done;
271 		}
272 
273 		afs_put_cell(cell);
274 		printk("kAFS: Added new cell '%s'\n", name);
275 	} else {
276 		goto inval;
277 	}
278 
279 	ret = size;
280 
281 done:
282 	kfree(kbuf);
283 	_leave(" = %d", ret);
284 	return ret;
285 
286 inval:
287 	ret = -EINVAL;
288 	printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
289 	goto done;
290 }
291 
292 static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
293 				      size_t size, loff_t *_pos)
294 {
295 	return 0;
296 }
297 
298 /*
299  * handle writes to /proc/fs/afs/rootcell
300  * - to initialize rootcell: echo "cell.name:192.168.231.14"
301  */
302 static ssize_t afs_proc_rootcell_write(struct file *file,
303 				       const char __user *buf,
304 				       size_t size, loff_t *_pos)
305 {
306 	char *kbuf, *s;
307 	int ret;
308 
309 	/* start by dragging the command into memory */
310 	if (size <= 1 || size >= PAGE_SIZE)
311 		return -EINVAL;
312 
313 	kbuf = memdup_user_nul(buf, size);
314 	if (IS_ERR(kbuf))
315 		return PTR_ERR(kbuf);
316 
317 	/* trim to first NL */
318 	s = memchr(kbuf, '\n', size);
319 	if (s)
320 		*s = 0;
321 
322 	/* determine command to perform */
323 	_debug("rootcell=%s", kbuf);
324 
325 	ret = afs_cell_init(kbuf);
326 	if (ret >= 0)
327 		ret = size;	/* consume everything, always */
328 
329 	kfree(kbuf);
330 	_leave(" = %d", ret);
331 	return ret;
332 }
333 
334 /*
335  * initialise /proc/fs/afs/<cell>/
336  */
337 int afs_proc_cell_setup(struct afs_cell *cell)
338 {
339 	struct proc_dir_entry *dir;
340 
341 	_enter("%p{%s}", cell, cell->name);
342 
343 	dir = proc_mkdir(cell->name, proc_afs);
344 	if (!dir)
345 		goto error_dir;
346 
347 	if (!proc_create_data("servers", 0, dir,
348 			     &afs_proc_cell_servers_fops, cell) ||
349 	    !proc_create_data("vlservers", 0, dir,
350 			     &afs_proc_cell_vlservers_fops, cell) ||
351 	    !proc_create_data("volumes", 0, dir,
352 			     &afs_proc_cell_volumes_fops, cell))
353 		goto error_tree;
354 
355 	_leave(" = 0");
356 	return 0;
357 
358 error_tree:
359 	remove_proc_subtree(cell->name, proc_afs);
360 error_dir:
361 	_leave(" = -ENOMEM");
362 	return -ENOMEM;
363 }
364 
365 /*
366  * remove /proc/fs/afs/<cell>/
367  */
368 void afs_proc_cell_remove(struct afs_cell *cell)
369 {
370 	_enter("");
371 
372 	remove_proc_subtree(cell->name, proc_afs);
373 
374 	_leave("");
375 }
376 
377 /*
378  * open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
379  */
380 static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
381 {
382 	struct afs_cell *cell;
383 	struct seq_file *m;
384 	int ret;
385 
386 	cell = PDE_DATA(inode);
387 	if (!cell)
388 		return -ENOENT;
389 
390 	ret = seq_open(file, &afs_proc_cell_volumes_ops);
391 	if (ret < 0)
392 		return ret;
393 
394 	m = file->private_data;
395 	m->private = cell;
396 
397 	return 0;
398 }
399 
400 /*
401  * set up the iterator to start reading from the cells list and return the
402  * first item
403  */
404 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
405 {
406 	struct afs_cell *cell = m->private;
407 
408 	_enter("cell=%p pos=%Ld", cell, *_pos);
409 
410 	/* lock the list against modification */
411 	down_read(&cell->vl_sem);
412 	return seq_list_start_head(&cell->vl_list, *_pos);
413 }
414 
415 /*
416  * move to next cell in cells list
417  */
418 static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
419 					loff_t *_pos)
420 {
421 	struct afs_cell *cell = p->private;
422 
423 	_enter("cell=%p pos=%Ld", cell, *_pos);
424 	return seq_list_next(v, &cell->vl_list, _pos);
425 }
426 
427 /*
428  * clean up after reading from the cells list
429  */
430 static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
431 {
432 	struct afs_cell *cell = p->private;
433 
434 	up_read(&cell->vl_sem);
435 }
436 
437 static const char afs_vlocation_states[][4] = {
438 	[AFS_VL_NEW]			= "New",
439 	[AFS_VL_CREATING]		= "Crt",
440 	[AFS_VL_VALID]			= "Val",
441 	[AFS_VL_NO_VOLUME]		= "NoV",
442 	[AFS_VL_UPDATING]		= "Upd",
443 	[AFS_VL_VOLUME_DELETED]		= "Del",
444 	[AFS_VL_UNCERTAIN]		= "Unc",
445 };
446 
447 /*
448  * display a header line followed by a load of volume lines
449  */
450 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
451 {
452 	struct afs_cell *cell = m->private;
453 	struct afs_vlocation *vlocation =
454 		list_entry(v, struct afs_vlocation, link);
455 
456 	/* display header on line 1 */
457 	if (v == &cell->vl_list) {
458 		seq_puts(m, "USE STT VLID[0]  VLID[1]  VLID[2]  NAME\n");
459 		return 0;
460 	}
461 
462 	/* display one cell per line on subsequent lines */
463 	seq_printf(m, "%3d %s %08x %08x %08x %s\n",
464 		   atomic_read(&vlocation->usage),
465 		   afs_vlocation_states[vlocation->state],
466 		   vlocation->vldb.vid[0],
467 		   vlocation->vldb.vid[1],
468 		   vlocation->vldb.vid[2],
469 		   vlocation->vldb.name);
470 
471 	return 0;
472 }
473 
474 /*
475  * open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
476  * location server
477  */
478 static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
479 {
480 	struct afs_cell *cell;
481 	struct seq_file *m;
482 	int ret;
483 
484 	cell = PDE_DATA(inode);
485 	if (!cell)
486 		return -ENOENT;
487 
488 	ret = seq_open(file, &afs_proc_cell_vlservers_ops);
489 	if (ret<0)
490 		return ret;
491 
492 	m = file->private_data;
493 	m->private = cell;
494 
495 	return 0;
496 }
497 
498 /*
499  * set up the iterator to start reading from the cells list and return the
500  * first item
501  */
502 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
503 {
504 	struct afs_cell *cell = m->private;
505 	loff_t pos = *_pos;
506 
507 	_enter("cell=%p pos=%Ld", cell, *_pos);
508 
509 	/* lock the list against modification */
510 	down_read(&cell->vl_sem);
511 
512 	/* allow for the header line */
513 	if (!pos)
514 		return (void *) 1;
515 	pos--;
516 
517 	if (pos >= cell->vl_naddrs)
518 		return NULL;
519 
520 	return &cell->vl_addrs[pos];
521 }
522 
523 /*
524  * move to next cell in cells list
525  */
526 static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
527 					  loff_t *_pos)
528 {
529 	struct afs_cell *cell = p->private;
530 	loff_t pos;
531 
532 	_enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
533 
534 	pos = *_pos;
535 	(*_pos)++;
536 	if (pos >= cell->vl_naddrs)
537 		return NULL;
538 
539 	return &cell->vl_addrs[pos];
540 }
541 
542 /*
543  * clean up after reading from the cells list
544  */
545 static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
546 {
547 	struct afs_cell *cell = p->private;
548 
549 	up_read(&cell->vl_sem);
550 }
551 
552 /*
553  * display a header line followed by a load of volume lines
554  */
555 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
556 {
557 	struct in_addr *addr = v;
558 
559 	/* display header on line 1 */
560 	if (v == (struct in_addr *) 1) {
561 		seq_puts(m, "ADDRESS\n");
562 		return 0;
563 	}
564 
565 	/* display one cell per line on subsequent lines */
566 	seq_printf(m, "%pI4\n", &addr->s_addr);
567 	return 0;
568 }
569 
570 /*
571  * open "/proc/fs/afs/<cell>/servers" which provides a summary of active
572  * servers
573  */
574 static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
575 {
576 	struct afs_cell *cell;
577 	struct seq_file *m;
578 	int ret;
579 
580 	cell = PDE_DATA(inode);
581 	if (!cell)
582 		return -ENOENT;
583 
584 	ret = seq_open(file, &afs_proc_cell_servers_ops);
585 	if (ret < 0)
586 		return ret;
587 
588 	m = file->private_data;
589 	m->private = cell;
590 	return 0;
591 }
592 
593 /*
594  * set up the iterator to start reading from the cells list and return the
595  * first item
596  */
597 static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
598 	__acquires(m->private->servers_lock)
599 {
600 	struct afs_cell *cell = m->private;
601 
602 	_enter("cell=%p pos=%Ld", cell, *_pos);
603 
604 	/* lock the list against modification */
605 	read_lock(&cell->servers_lock);
606 	return seq_list_start_head(&cell->servers, *_pos);
607 }
608 
609 /*
610  * move to next cell in cells list
611  */
612 static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
613 					loff_t *_pos)
614 {
615 	struct afs_cell *cell = p->private;
616 
617 	_enter("cell=%p pos=%Ld", cell, *_pos);
618 	return seq_list_next(v, &cell->servers, _pos);
619 }
620 
621 /*
622  * clean up after reading from the cells list
623  */
624 static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
625 	__releases(p->private->servers_lock)
626 {
627 	struct afs_cell *cell = p->private;
628 
629 	read_unlock(&cell->servers_lock);
630 }
631 
632 /*
633  * display a header line followed by a load of volume lines
634  */
635 static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
636 {
637 	struct afs_cell *cell = m->private;
638 	struct afs_server *server = list_entry(v, struct afs_server, link);
639 	char ipaddr[20];
640 
641 	/* display header on line 1 */
642 	if (v == &cell->servers) {
643 		seq_puts(m, "USE ADDR            STATE\n");
644 		return 0;
645 	}
646 
647 	/* display one cell per line on subsequent lines */
648 	sprintf(ipaddr, "%pI4", &server->addr);
649 	seq_printf(m, "%3d %-15.15s %5d\n",
650 		   atomic_read(&server->usage), ipaddr, server->fs_state);
651 
652 	return 0;
653 }
654