fs/afs/proc.c

   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 = 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 }