xref: /openbmc/linux/fs/afs/proc.c (revision eb3fcf00) 
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 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 = 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 
286 done:
287 	kfree(kbuf);
288 	_leave(" = %d", ret);
289 	return ret;
290 
291 inval:
292 	ret = -EINVAL;
293 	printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
294 	goto done;
295 }
296 
297 static 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  */
307 static 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 
340 infault:
341 	kfree(kbuf);
342 nomem:
343 	_leave(" = %d", ret);
344 	return ret;
345 }
346 
347 /*
348  * initialise /proc/fs/afs/<cell>/
349  */
350 int 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 
371 error_tree:
372 	remove_proc_subtree(cell->name, proc_afs);
373 error_dir:
374 	_leave(" = -ENOMEM");
375 	return -ENOMEM;
376 }
377 
378 /*
379  * remove /proc/fs/afs/<cell>/
380  */
381 void 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  */
393 static 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  */
417 static 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  */
431 static 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  */
443 static 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 
450 static 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  */
463 static 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  */
491 static 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  */
515 static 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  */
539 static 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  */
558 static 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  */
568 static 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  */
587 static 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  */
610 static 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  */
625 static 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  */
637 static 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  */
648 static 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 }
667