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 <linux/uaccess.h>
  18 #include "internal.h"
  19
  20 static inline struct afs_net *afs_seq2net(struct seq_file *m)
  21 {
  22         return afs_net(seq_file_net(m));
  23 }
  24
  25 static inline struct afs_net *afs_seq2net_single(struct seq_file *m)
  26 {
  27         return afs_net(seq_file_single_net(m));
  28 }
  29
  30 /*
  31  * Display the list of cells known to the namespace.
  32  */
  33 static int afs_proc_cells_show(struct seq_file *m, void *v)
  34 {
  35         struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
  36         struct afs_net *net = afs_seq2net(m);
  37
  38         if (v == &net->proc_cells) {
  39                 /* display header on line 1 */
  40                 seq_puts(m, "USE NAME\n");
  41                 return 0;
  42         }
  43
  44         /* display one cell per line on subsequent lines */
  45         seq_printf(m, "%3u %s\n", atomic_read(&cell->usage), cell->name);
  46         return 0;
  47 }
  48
  49 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
  50         __acquires(rcu)
  51 {
  52         rcu_read_lock();
  53         return seq_list_start_head(&afs_seq2net(m)->proc_cells, *_pos);
  54 }
  55
  56 static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)
  57 {
  58         return seq_list_next(v, &afs_seq2net(m)->proc_cells, pos);
  59 }
  60
  61 static void afs_proc_cells_stop(struct seq_file *m, void *v)
  62         __releases(rcu)
  63 {
  64         rcu_read_unlock();
  65 }
  66
  67 static const struct seq_operations afs_proc_cells_ops = {
  68         .start  = afs_proc_cells_start,
  69         .next   = afs_proc_cells_next,
  70         .stop   = afs_proc_cells_stop,
  71         .show   = afs_proc_cells_show,
  72 };
  73
  74 /*
  75  * handle writes to /proc/fs/afs/cells
  76  * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
  77  */
  78 static int afs_proc_cells_write(struct file *file, char *buf, size_t size)
  79 {
  80         struct seq_file *m = file->private_data;
  81         struct afs_net *net = afs_seq2net(m);
  82         char *name, *args;
  83         int ret;
  84
  85         /* trim to first NL */
  86         name = memchr(buf, '\n', size);
  87         if (name)
  88                 *name = 0;
  89
  90         /* split into command, name and argslist */
  91         name = strchr(buf, ' ');
  92         if (!name)
  93                 goto inval;
  94         do {
  95                 *name++ = 0;
  96         } while(*name == ' ');
  97         if (!*name)
  98                 goto inval;
  99
 100         args = strchr(name, ' ');
 101         if (args) {
 102                 do {
 103                         *args++ = 0;
 104                 } while(*args == ' ');
 105                 if (!*args)
 106                         goto inval;
 107         }
 108
 109         /* determine command to perform */
 110         _debug("cmd=%s name=%s args=%s", buf, name, args);
 111
 112         if (strcmp(buf, "add") == 0) {
 113                 struct afs_cell *cell;
 114
 115                 cell = afs_lookup_cell(net, name, strlen(name), args, true);
 116                 if (IS_ERR(cell)) {
 117                         ret = PTR_ERR(cell);
 118                         goto done;
 119                 }
 120
 121                 if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags))
 122                         afs_put_cell(net, cell);
 123         } else {
 124                 goto inval;
 125         }
 126
 127         ret = 0;
 128
 129 done:
 130         _leave(" = %d", ret);
 131         return ret;
 132
 133 inval:
 134         ret = -EINVAL;
 135         printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
 136         goto done;
 137 }
 138
 139 /*
 140  * Display the name of the current workstation cell.
 141  */
 142 static int afs_proc_rootcell_show(struct seq_file *m, void *v)
 143 {
 144         struct afs_cell *cell;
 145         struct afs_net *net;
 146
 147         net = afs_seq2net_single(m);
 148         if (rcu_access_pointer(net->ws_cell)) {
 149                 rcu_read_lock();
 150                 cell = rcu_dereference(net->ws_cell);
 151                 if (cell)
 152                         seq_printf(m, "%s\n", cell->name);
 153                 rcu_read_unlock();
 154         }
 155         return 0;
 156 }
 157
 158 /*
 159  * Set the current workstation cell and optionally supply its list of volume
 160  * location servers.
 161  *
 162  *      echo "cell.name:192.168.231.14" >/proc/fs/afs/rootcell
 163  */
 164 static int afs_proc_rootcell_write(struct file *file, char *buf, size_t size)
 165 {
 166         struct seq_file *m = file->private_data;
 167         struct afs_net *net = afs_seq2net_single(m);
 168         char *s;
 169         int ret;
 170
 171         ret = -EINVAL;
 172         if (buf[0] == '.')
 173                 goto out;
 174         if (memchr(buf, '/', size))
 175                 goto out;
 176
 177         /* trim to first NL */
 178         s = memchr(buf, '\n', size);
 179         if (s)
 180                 *s = 0;
 181
 182         /* determine command to perform */
 183         _debug("rootcell=%s", buf);
 184
 185         ret = afs_cell_init(net, buf);
 186
 187 out:
 188         _leave(" = %d", ret);
 189         return ret;
 190 }
 191
 192 static const char afs_vol_types[3][3] = {
 193         [AFSVL_RWVOL]   = "RW",
 194         [AFSVL_ROVOL]   = "RO",
 195         [AFSVL_BACKVOL] = "BK",
 196 };
 197
 198 /*
 199  * Display the list of volumes known to a cell.
 200  */
 201 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
 202 {
 203         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 204         struct afs_volume *vol = list_entry(v, struct afs_volume, proc_link);
 205
 206         /* Display header on line 1 */
 207         if (v == &cell->proc_volumes) {
 208                 seq_puts(m, "USE VID      TY\n");
 209                 return 0;
 210         }
 211
 212         seq_printf(m, "%3d %08x %s\n",
 213                    atomic_read(&vol->usage), vol->vid,
 214                    afs_vol_types[vol->type]);
 215
 216         return 0;
 217 }
 218
 219 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
 220         __acquires(cell->proc_lock)
 221 {
 222         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 223
 224         read_lock(&cell->proc_lock);
 225         return seq_list_start_head(&cell->proc_volumes, *_pos);
 226 }
 227
 228 static void *afs_proc_cell_volumes_next(struct seq_file *m, void *v,
 229                                         loff_t *_pos)
 230 {
 231         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 232
 233         return seq_list_next(v, &cell->proc_volumes, _pos);
 234 }
 235
 236 static void afs_proc_cell_volumes_stop(struct seq_file *m, void *v)
 237         __releases(cell->proc_lock)
 238 {
 239         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 240
 241         read_unlock(&cell->proc_lock);
 242 }
 243
 244 static const struct seq_operations afs_proc_cell_volumes_ops = {
 245         .start  = afs_proc_cell_volumes_start,
 246         .next   = afs_proc_cell_volumes_next,
 247         .stop   = afs_proc_cell_volumes_stop,
 248         .show   = afs_proc_cell_volumes_show,
 249 };
 250
 251 /*
 252  * Display the list of Volume Location servers we're using for a cell.
 253  */
 254 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
 255 {
 256         struct sockaddr_rxrpc *addr = v;
 257
 258         /* display header on line 1 */
 259         if (v == (void *)1) {
 260                 seq_puts(m, "ADDRESS\n");
 261                 return 0;
 262         }
 263
 264         /* display one cell per line on subsequent lines */
 265         seq_printf(m, "%pISp\n", &addr->transport);
 266         return 0;
 267 }
 268
 269 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
 270         __acquires(rcu)
 271 {
 272         struct afs_addr_list *alist;
 273         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 274         loff_t pos = *_pos;
 275
 276         rcu_read_lock();
 277
 278         alist = rcu_dereference(cell->vl_addrs);
 279
 280         /* allow for the header line */
 281         if (!pos)
 282                 return (void *) 1;
 283         pos--;
 284
 285         if (!alist || pos >= alist->nr_addrs)
 286                 return NULL;
 287
 288         return alist->addrs + pos;
 289 }
 290
 291 static void *afs_proc_cell_vlservers_next(struct seq_file *m, void *v,
 292                                           loff_t *_pos)
 293 {
 294         struct afs_addr_list *alist;
 295         struct afs_cell *cell = PDE_DATA(file_inode(m->file));
 296         loff_t pos;
 297
 298         alist = rcu_dereference(cell->vl_addrs);
 299
 300         pos = *_pos;
 301         (*_pos)++;
 302         if (!alist || pos >= alist->nr_addrs)
 303                 return NULL;
 304
 305         return alist->addrs + pos;
 306 }
 307
 308 static void afs_proc_cell_vlservers_stop(struct seq_file *m, void *v)
 309         __releases(rcu)
 310 {
 311         rcu_read_unlock();
 312 }
 313
 314 static const struct seq_operations afs_proc_cell_vlservers_ops = {
 315         .start  = afs_proc_cell_vlservers_start,
 316         .next   = afs_proc_cell_vlservers_next,
 317         .stop   = afs_proc_cell_vlservers_stop,
 318         .show   = afs_proc_cell_vlservers_show,
 319 };
 320
 321 /*
 322  * Display the list of fileservers we're using within a namespace.
 323  */
 324 static int afs_proc_servers_show(struct seq_file *m, void *v)
 325 {
 326         struct afs_server *server;
 327         struct afs_addr_list *alist;
 328         int i;
 329
 330         if (v == SEQ_START_TOKEN) {
 331                 seq_puts(m, "UUID                                 USE ADDR\n");
 332                 return 0;
 333         }
 334
 335         server = list_entry(v, struct afs_server, proc_link);
 336         alist = rcu_dereference(server->addresses);
 337         seq_printf(m, "%pU %3d %pISpc%s\n",
 338                    &server->uuid,
 339                    atomic_read(&server->usage),
 340                    &alist->addrs[0].transport,
 341                    alist->index == 0 ? "*" : "");
 342         for (i = 1; i < alist->nr_addrs; i++)
 343                 seq_printf(m, "                                         %pISpc%s\n",
 344                            &alist->addrs[i].transport,
 345                            alist->index == i ? "*" : "");
 346         return 0;
 347 }
 348
 349 static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)
 350         __acquires(rcu)
 351 {
 352         rcu_read_lock();
 353         return seq_hlist_start_head_rcu(&afs_seq2net(m)->fs_proc, *_pos);
 354 }
 355
 356 static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)
 357 {
 358         return seq_hlist_next_rcu(v, &afs_seq2net(m)->fs_proc, _pos);
 359 }
 360
 361 static void afs_proc_servers_stop(struct seq_file *m, void *v)
 362         __releases(rcu)
 363 {
 364         rcu_read_unlock();
 365 }
 366
 367 static const struct seq_operations afs_proc_servers_ops = {
 368         .start  = afs_proc_servers_start,
 369         .next   = afs_proc_servers_next,
 370         .stop   = afs_proc_servers_stop,
 371         .show   = afs_proc_servers_show,
 372 };
 373
 374 /*
 375  * Display the list of strings that may be substituted for the @sys pathname
 376  * macro.
 377  */
 378 static int afs_proc_sysname_show(struct seq_file *m, void *v)
 379 {
 380         struct afs_net *net = afs_seq2net(m);
 381         struct afs_sysnames *sysnames = net->sysnames;
 382         unsigned int i = (unsigned long)v - 1;
 383
 384         if (i < sysnames->nr)
 385                 seq_printf(m, "%s\n", sysnames->subs[i]);
 386         return 0;
 387 }
 388
 389 static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos)
 390         __acquires(&net->sysnames_lock)
 391 {
 392         struct afs_net *net = afs_seq2net(m);
 393         struct afs_sysnames *names;
 394
 395         read_lock(&net->sysnames_lock);
 396
 397         names = net->sysnames;
 398         if (*pos >= names->nr)
 399                 return NULL;
 400         return (void *)(unsigned long)(*pos + 1);
 401 }
 402
 403 static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos)
 404 {
 405         struct afs_net *net = afs_seq2net(m);
 406         struct afs_sysnames *names = net->sysnames;
 407
 408         *pos += 1;
 409         if (*pos >= names->nr)
 410                 return NULL;
 411         return (void *)(unsigned long)(*pos + 1);
 412 }
 413
 414 static void afs_proc_sysname_stop(struct seq_file *m, void *v)
 415         __releases(&net->sysnames_lock)
 416 {
 417         struct afs_net *net = afs_seq2net(m);
 418
 419         read_unlock(&net->sysnames_lock);
 420 }
 421
 422 static const struct seq_operations afs_proc_sysname_ops = {
 423         .start  = afs_proc_sysname_start,
 424         .next   = afs_proc_sysname_next,
 425         .stop   = afs_proc_sysname_stop,
 426         .show   = afs_proc_sysname_show,
 427 };
 428
 429 /*
 430  * Allow the @sys substitution to be configured.
 431  */
 432 static int afs_proc_sysname_write(struct file *file, char *buf, size_t size)
 433 {
 434         struct afs_sysnames *sysnames, *kill;
 435         struct seq_file *m = file->private_data;
 436         struct afs_net *net = afs_seq2net(m);
 437         char *s, *p, *sub;
 438         int ret, len;
 439
 440         sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
 441         if (!sysnames)
 442                 return -ENOMEM;
 443         refcount_set(&sysnames->usage, 1);
 444         kill = sysnames;
 445
 446         p = buf;
 447         while ((s = strsep(&p, " \t\n"))) {
 448                 len = strlen(s);
 449                 if (len == 0)
 450                         continue;
 451                 ret = -ENAMETOOLONG;
 452                 if (len >= AFSNAMEMAX)
 453                         goto error;
 454
 455                 if (len >= 4 &&
 456                     s[len - 4] == '@' &&
 457                     s[len - 3] == 's' &&
 458                     s[len - 2] == 'y' &&
 459                     s[len - 1] == 's')
 460                         /* Protect against recursion */
 461                         goto invalid;
 462
 463                 if (s[0] == '.' &&
 464                     (len < 2 || (len == 2 && s[1] == '.')))
 465                         goto invalid;
 466
 467                 if (memchr(s, '/', len))
 468                         goto invalid;
 469
 470                 ret = -EFBIG;
 471                 if (sysnames->nr >= AFS_NR_SYSNAME)
 472                         goto out;
 473
 474                 if (strcmp(s, afs_init_sysname) == 0) {
 475                         sub = (char *)afs_init_sysname;
 476                 } else {
 477                         ret = -ENOMEM;
 478                         sub = kmemdup(s, len + 1, GFP_KERNEL);
 479                         if (!sub)
 480                                 goto out;
 481                 }
 482
 483                 sysnames->subs[sysnames->nr] = sub;
 484                 sysnames->nr++;
 485         }
 486
 487         if (sysnames->nr == 0) {
 488                 sysnames->subs[0] = sysnames->blank;
 489                 sysnames->nr++;
 490         }
 491
 492         write_lock(&net->sysnames_lock);
 493         kill = net->sysnames;
 494         net->sysnames = sysnames;
 495         write_unlock(&net->sysnames_lock);
 496         ret = 0;
 497 out:
 498         afs_put_sysnames(kill);
 499         return ret;
 500
 501 invalid:
 502         ret = -EINVAL;
 503 error:
 504         goto out;
 505 }
 506
 507 void afs_put_sysnames(struct afs_sysnames *sysnames)
 508 {
 509         int i;
 510
 511         if (sysnames && refcount_dec_and_test(&sysnames->usage)) {
 512                 for (i = 0; i < sysnames->nr; i++)
 513                         if (sysnames->subs[i] != afs_init_sysname &&
 514                             sysnames->subs[i] != sysnames->blank)
 515                                 kfree(sysnames->subs[i]);
 516         }
 517 }
 518
 519 /*
 520  * Display general per-net namespace statistics
 521  */
 522 static int afs_proc_stats_show(struct seq_file *m, void *v)
 523 {
 524         struct afs_net *net = afs_seq2net_single(m);
 525
 526         seq_puts(m, "kAFS statistics\n");
 527
 528         seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n",
 529                    atomic_read(&net->n_lookup),
 530                    atomic_read(&net->n_reval),
 531                    atomic_read(&net->n_inval),
 532                    atomic_read(&net->n_relpg));
 533
 534         seq_printf(m, "dir-data: rdpg=%u\n",
 535                    atomic_read(&net->n_read_dir));
 536
 537         seq_printf(m, "dir-edit: cr=%u rm=%u\n",
 538                    atomic_read(&net->n_dir_cr),
 539                    atomic_read(&net->n_dir_rm));
 540
 541         seq_printf(m, "file-rd : n=%u nb=%lu\n",
 542                    atomic_read(&net->n_fetches),
 543                    atomic_long_read(&net->n_fetch_bytes));
 544         seq_printf(m, "file-wr : n=%u nb=%lu\n",
 545                    atomic_read(&net->n_stores),
 546                    atomic_long_read(&net->n_store_bytes));
 547         return 0;
 548 }
 549
 550 /*
 551  * initialise /proc/fs/afs/<cell>/
 552  */
 553 int afs_proc_cell_setup(struct afs_cell *cell)
 554 {
 555         struct proc_dir_entry *dir;
 556         struct afs_net *net = cell->net;
 557
 558         _enter("%p{%s},%p", cell, cell->name, net->proc_afs);
 559
 560         dir = proc_net_mkdir(net->net, cell->name, net->proc_afs);
 561         if (!dir)
 562                 goto error_dir;
 563
 564         if (!proc_create_net_data("vlservers", 0444, dir,
 565                                   &afs_proc_cell_vlservers_ops,
 566                                   sizeof(struct seq_net_private),
 567                                   cell) ||
 568             !proc_create_net_data("volumes", 0444, dir,
 569                                   &afs_proc_cell_volumes_ops,
 570                                   sizeof(struct seq_net_private),
 571                                   cell))
 572                 goto error_tree;
 573
 574         _leave(" = 0");
 575         return 0;
 576
 577 error_tree:
 578         remove_proc_subtree(cell->name, net->proc_afs);
 579 error_dir:
 580         _leave(" = -ENOMEM");
 581         return -ENOMEM;
 582 }
 583
 584 /*
 585  * remove /proc/fs/afs/<cell>/
 586  */
 587 void afs_proc_cell_remove(struct afs_cell *cell)
 588 {
 589         struct afs_net *net = cell->net;
 590
 591         _enter("");
 592         remove_proc_subtree(cell->name, net->proc_afs);
 593         _leave("");
 594 }
 595
 596 /*
 597  * initialise the /proc/fs/afs/ directory
 598  */
 599 int afs_proc_init(struct afs_net *net)
 600 {
 601         struct proc_dir_entry *p;
 602
 603         _enter("");
 604
 605         p = proc_net_mkdir(net->net, "afs", net->net->proc_net);
 606         if (!p)
 607                 goto error_dir;
 608
 609         if (!proc_create_net_data_write("cells", 0644, p,
 610                                         &afs_proc_cells_ops,
 611                                         afs_proc_cells_write,
 612                                         sizeof(struct seq_net_private),
 613                                         NULL) ||
 614             !proc_create_net_single_write("rootcell", 0644, p,
 615                                           afs_proc_rootcell_show,
 616                                           afs_proc_rootcell_write,
 617                                           NULL) ||
 618             !proc_create_net("servers", 0444, p, &afs_proc_servers_ops,
 619                              sizeof(struct seq_net_private)) ||
 620             !proc_create_net_single("stats", 0444, p, afs_proc_stats_show, NULL) ||
 621             !proc_create_net_data_write("sysname", 0644, p,
 622                                         &afs_proc_sysname_ops,
 623                                         afs_proc_sysname_write,
 624                                         sizeof(struct seq_net_private),
 625                                         NULL))
 626                 goto error_tree;
 627
 628         net->proc_afs = p;
 629         _leave(" = 0");
 630         return 0;
 631
 632 error_tree:
 633         proc_remove(p);
 634 error_dir:
 635         _leave(" = -ENOMEM");
 636         return -ENOMEM;
 637 }
 638
 639 /*
 640  * clean up the /proc/fs/afs/ directory
 641  */
 642 void afs_proc_cleanup(struct afs_net *net)
 643 {
 644         proc_remove(net->proc_afs);
 645         net->proc_afs = NULL;
 646 }