lustre/obdclass/class_obd.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  *              An implementation of a loadable kernel mode driver providing
   5  *              multiple kernel/user space bidirectional communications links.
   6  *
   7  *              Author:         Alan Cox <alan@cymru.net>
   8  *
   9  *              This program is free software; you can redistribute it and/or
  10  *              modify it under the terms of the GNU General Public License
  11  *              version 2 as published by the Free Software Foundation.
  12  *
  13  *              Adapted to become the Linux 2.0 Coda pseudo device
  14  *              Peter  Braam  <braam@maths.ox.ac.uk>
  15  *              Michael Callahan <mjc@emmy.smith.edu>
  16  *
  17  *              Changes for Linux 2.1
  18  *              Copyright (c) 1997 Carnegie-Mellon University
  19  *
  20  *              Redone again for Intermezzo
  21  *              Copyright (c) 1998 Peter J. Braam
  22  *
  23  *              Hacked up again for simulated OBD
  24  *              Copyright (c) 1999 Stelias Computing, Inc.
  25  *                (authors {pschwan,braam}@stelias.com)
  26  *              Copyright (C) 1999 Seagate Technology, Inc.
  27  *              Copyright (C) 2001 Cluster File Systems, Inc.
  28  *
  29  *
  30  */
  31
  32 #define EXPORT_SYMTAB
  33 #include <linux/config.h> /* for CONFIG_PROC_FS */
  34 #include <linux/module.h>
  35 #include <linux/errno.h>
  36 #include <linux/kernel.h>
  37 #include <linux/major.h>
  38 #include <linux/kmod.h>   /* for request_module() */
  39 #include <linux/sched.h>
  40 #include <linux/lp.h>
  41 #include <linux/slab.h>
  42 #include <linux/ioport.h>
  43 #include <linux/fcntl.h>
  44 #include <linux/delay.h>
  45 #include <linux/skbuff.h>
  46 #include <linux/proc_fs.h>
  47 #include <linux/fs.h>
  48 #include <linux/poll.h>
  49 #include <linux/init.h>
  50 #include <linux/list.h>
  51 #include <asm/io.h>
  52 #include <asm/system.h>
  53 #include <asm/poll.h>
  54 #include <asm/uaccess.h>
  55 #include <linux/miscdevice.h>
  56
  57 #define DEBUG_SUBSYSTEM S_CLASS
  58
  59 #include <linux/obd_support.h>
  60 #include <linux/obd_class.h>
  61
  62 static int obd_init_magic;
  63 unsigned long obd_memory = 0;
  64 unsigned long obd_fail_loc = 0;
  65 struct obd_device obd_dev[MAX_OBD_DEVICES];
  66 struct list_head obd_types;
  67
  68 /*  opening /dev/obd */
  69 static int obd_class_open(struct inode * inode, struct file * file)
  70 {
  71         ENTRY;
  72
  73         file->private_data = NULL;
  74         MOD_INC_USE_COUNT;
  75         RETURN(0);
  76 }
  77
  78 /*  closing /dev/obd */
  79 static int obd_class_release(struct inode * inode, struct file * file)
  80 {
  81         ENTRY;
  82
  83         if (file->private_data)
  84                 file->private_data = NULL;
  85
  86         MOD_DEC_USE_COUNT;
  87         RETURN(0);
  88 }
  89
  90 /*
  91  * support functions: we could use inter-module communication, but this
  92  * is more portable to other OS's
  93  */
  94 static struct obd_type *obd_search_type(char *nm)
  95 {
  96         struct list_head *tmp;
  97         struct obd_type *type;
  98         CDEBUG(D_INFO, "SEARCH %s\n", nm);
  99
 100         tmp = &obd_types;
 101         while ( (tmp = tmp->next) != &obd_types ) {
 102                 type = list_entry(tmp, struct obd_type, typ_chain);
 103                 CDEBUG(D_INFO, "TYP %s\n", type->typ_name);
 104                 if (strlen(type->typ_name) == strlen(nm) &&
 105                     strcmp(type->typ_name, nm) == 0 ) {
 106                         return type;
 107                 }
 108         }
 109         return NULL;
 110 }
 111
 112 static struct obd_type *obd_nm_to_type(char *nm)
 113 {
 114         struct obd_type *type = obd_search_type(nm);
 115
 116 #ifdef CONFIG_KMOD
 117         if ( !type ) {
 118                 if ( !request_module(nm) ) {
 119                         CDEBUG(D_INFO, "Loaded module '%s'\n", nm);
 120                         type = obd_search_type(nm);
 121                 } else {
 122                         CDEBUG(D_INFO, "Can't load module '%s'\n", nm);
 123                 }
 124         }
 125 #endif
 126         return type;
 127 }
 128
 129 /* to control /dev/obd */
 130 static int obd_class_ioctl (struct inode * inode, struct file * filp,
 131                             unsigned int cmd, unsigned long arg)
 132 {
 133         /* NOTE this must be larger than any of the ioctl data structs */
 134         char buf[1024];
 135         struct obd_ioctl_data *data;
 136         struct obd_device *obd = filp->private_data;
 137         struct obd_conn conn;
 138         int rw = OBD_BRW_READ;
 139         int err = 0;
 140         ENTRY;
 141
 142         memset(buf, 0, sizeof(buf));
 143
 144         if (!obd && cmd != OBD_IOC_DEVICE && cmd != TCGETS) {
 145                 CERROR("OBD ioctl: No device\n");
 146                 RETURN(-EINVAL);
 147         }
 148         if (obd_ioctl_getdata(buf, buf + 800, (void *)arg)) {
 149                 CERROR("OBD ioctl: data error\n");
 150                 RETURN(-EINVAL);
 151         }
 152         data = (struct obd_ioctl_data *)buf;
 153
 154         switch (cmd) {
 155         case TCGETS:
 156                 RETURN(-EINVAL);
 157         case OBD_IOC_DEVICE: {
 158                 CDEBUG(D_IOCTL, "\n");
 159                 if (data->ioc_dev >= MAX_OBD_DEVICES ||
 160                     data->ioc_dev < 0) {
 161                         CERROR("OBD ioctl: DEVICE insufficient devices\n");
 162                         RETURN(-EINVAL);
 163                 }
 164                 CDEBUG(D_IOCTL, "device %d\n", data->ioc_dev);
 165
 166                 filp->private_data = &obd_dev[data->ioc_dev];
 167                 RETURN(0);
 168         }
 169
 170         case OBD_IOC_ATTACH: {
 171                 struct obd_type *type;
 172
 173                 /* have we attached a type to this device */
 174                 if (obd->obd_flags & OBD_ATTACHED) {
 175                         CERROR("OBD: Device %d already typed as  %s.\n",
 176                                obd->obd_minor, MKSTR(obd->obd_type->typ_name));
 177                         RETURN(-EBUSY);
 178                 }
 179
 180                 CDEBUG(D_IOCTL, "attach %s %s\n",  MKSTR(data->ioc_inlbuf1),
 181                        MKSTR(data->ioc_inlbuf2));
 182
 183                 /* find the type */
 184                 type = obd_nm_to_type(data->ioc_inlbuf1);
 185                 if (!type) {
 186                         CERROR("OBD: unknown type dev %d\n", obd->obd_minor);
 187                         RETURN(-EINVAL);
 188                 }
 189
 190                 obd->obd_type = type;
 191                 obd->obd_multi_count = 0;
 192                 INIT_LIST_HEAD(&obd->obd_gen_clients);
 193                 INIT_LIST_HEAD(&obd->obd_req_list);
 194
 195                 /* do the attach */
 196                 if (OBT(obd) && OBP(obd, attach))
 197                         err = OBP(obd, attach)(obd, sizeof(*data), data);
 198
 199                 if (err) {
 200                         obd->obd_type = NULL;
 201                 } else {
 202                         obd->obd_flags |=  OBD_ATTACHED;
 203                         type->typ_refcnt++;
 204                         CDEBUG(D_IOCTL, "OBD: dev %d attached type %s\n",
 205                                obd->obd_minor, data->ioc_inlbuf1);
 206                         obd->obd_proc_entry =
 207                                 proc_lustre_register_obd_device(obd);
 208                         MOD_INC_USE_COUNT;
 209                 }
 210
 211                 RETURN(err);
 212         }
 213
 214         case OBD_IOC_DETACH: {
 215                 ENTRY;
 216                 if (obd->obd_flags & OBD_SET_UP) {
 217                         CERROR("OBD device %d still set up\n", obd->obd_minor);
 218                         RETURN(-EBUSY);
 219                 }
 220                 if (! (obd->obd_flags & OBD_ATTACHED) ) {
 221                         CERROR("OBD device %d not attached\n", obd->obd_minor);
 222                         RETURN(-ENODEV);
 223                 }
 224                 if ( !list_empty(&obd->obd_gen_clients) ) {
 225                         CERROR("OBD device %d has connected clients\n",
 226                                obd->obd_minor);
 227                         RETURN(-EBUSY);
 228                 }
 229                 if ( !list_empty(&obd->obd_req_list) ) {
 230                         CERROR("OBD device %d has hanging requests\n",
 231                                obd->obd_minor);
 232                         RETURN(-EBUSY);
 233                 }
 234
 235                 if (obd->obd_proc_entry)
 236                         proc_lustre_release_obd_device(obd);
 237
 238                 obd->obd_flags &= ~OBD_ATTACHED;
 239                 obd->obd_type->typ_refcnt--;
 240                 obd->obd_type = NULL;
 241                 MOD_DEC_USE_COUNT;
 242                 RETURN(0);
 243         }
 244
 245         case OBD_IOC_SETUP: {
 246                 /* have we attached a type to this device? */
 247                 if (!(obd->obd_flags & OBD_ATTACHED)) {
 248                         CERROR("Device %d not attached\n", obd->obd_minor);
 249                         RETURN(-ENODEV);
 250                 }
 251
 252                 /* has this been done already? */
 253                 if ( obd->obd_flags & OBD_SET_UP ) {
 254                         CERROR("Device %d already setup (type %s)\n",
 255                                obd->obd_minor, obd->obd_type->typ_name);
 256                         RETURN(-EBUSY);
 257                 }
 258
 259                 if ( OBT(obd) && OBP(obd, setup) )
 260                         err = obd_setup(obd, sizeof(*data), data);
 261
 262                 if (!err) {
 263                         obd->obd_type->typ_refcnt++;
 264                         obd->obd_flags |= OBD_SET_UP;
 265                 }
 266
 267                 RETURN(err);
 268         }
 269         case OBD_IOC_CLEANUP: {
 270                 /* have we attached a type to this device? */
 271                 if (!(obd->obd_flags & OBD_ATTACHED)) {
 272                         CERROR("Device %d not attached\n", obd->obd_minor);
 273                         RETURN(-ENODEV);
 274                 }
 275
 276                 if ( OBT(obd) && OBP(obd, cleanup) )
 277                         err = obd_cleanup(obd);
 278
 279                 if (!err) {
 280                         obd->obd_flags &= ~OBD_SET_UP;
 281                         obd->obd_type->typ_refcnt--;
 282                 }
 283                 RETURN(err);
 284         }
 285
 286         case OBD_IOC_CONNECT: {
 287                 conn.oc_id = data->ioc_conn1;
 288                 conn.oc_dev = obd;
 289
 290                 err = obd_connect(&conn);
 291
 292                 CDEBUG(D_IOCTL, "assigned connection %d\n", conn.oc_id);
 293                 data->ioc_conn1 = conn.oc_id;
 294                 if (err)
 295                         RETURN(err);
 296
 297                 err = copy_to_user((int *)arg, data, sizeof(*data));
 298                 RETURN(err);
 299         }
 300
 301         case OBD_IOC_DISCONNECT: {
 302                 conn.oc_id = data->ioc_conn1;
 303                 conn.oc_dev = obd;
 304
 305                 err = obd_disconnect(&conn);
 306                 RETURN(err);
 307         }
 308
 309         case OBD_IOC_DEC_USE_COUNT: {
 310                 MOD_DEC_USE_COUNT;
 311                 RETURN(0);
 312         }
 313
 314         case OBD_IOC_CREATE: {
 315                 conn.oc_id = data->ioc_conn1;
 316                 conn.oc_dev = obd;
 317
 318                 err = obd_create(&conn, &data->ioc_obdo1);
 319                 if (err)
 320                         RETURN(err);
 321
 322                 err = copy_to_user((int *)arg, data, sizeof(*data));
 323                 RETURN(err);
 324         }
 325
 326         case OBD_IOC_GETATTR: {
 327                 conn.oc_id = data->ioc_conn1;
 328                 conn.oc_dev = obd;
 329
 330                 err = obd_getattr(&conn, &data->ioc_obdo1);
 331                 if (err)
 332                         RETURN(err);
 333
 334                 err = copy_to_user((int *)arg, data, sizeof(*data));
 335                 RETURN(err);
 336         }
 337
 338         case OBD_IOC_SETATTR: {
 339                 conn.oc_id = data->ioc_conn1;
 340                 conn.oc_dev = obd;
 341
 342                 err = obd_setattr(&conn, &data->ioc_obdo1);
 343                 if (err)
 344                         RETURN(err);
 345
 346                 err = copy_to_user((int *)arg, data, sizeof(*data));
 347                 RETURN(err);
 348         }
 349
 350         case OBD_IOC_DESTROY: {
 351                 conn.oc_id = data->ioc_conn1;
 352                 conn.oc_dev = obd;
 353
 354                 err = obd_destroy(&conn, &data->ioc_obdo1);
 355                 if (err)
 356                         RETURN(err);
 357
 358                 err = copy_to_user((int *)arg, data, sizeof(*data));
 359                 RETURN(err);
 360         }
 361
 362         case OBD_IOC_BRW_WRITE:
 363                 rw = OBD_BRW_WRITE;
 364         case OBD_IOC_BRW_READ: {
 365                 /* FIXME: use a better ioctl data struct than obd_ioctl_data.
 366                  *        We don't really support multiple-obdo I/Os here,
 367                  *        for example offset and count are not per-obdo.
 368                  */
 369                 struct obd_conn conns[2];
 370                 struct obdo     *obdos[2] = { NULL, NULL };
 371                 obd_count       oa_bufs[2] = { 0, 0 };
 372                 struct page     **bufs = NULL;
 373                 obd_size        *counts = NULL;
 374                 obd_off         *offsets = NULL;
 375                 obd_flag        *flags = NULL;
 376                 int             num = 1;
 377                 int             pages;
 378                 int             i, j;
 379
 380                 pages = oa_bufs[0] = data->ioc_plen1 / PAGE_SIZE;
 381                 if (data->ioc_obdo2.o_id) {
 382                         num = 2;
 383                         oa_bufs[1] = data->ioc_plen2 / PAGE_SIZE;
 384                         pages += oa_bufs[1];
 385                 }
 386
 387                 CDEBUG(D_INODE, "BRW %s with %dx%d pages\n",
 388                        rw == OBD_BRW_READ ? "read" : "write",
 389                        num, oa_bufs[0]);
 390                 bufs = kmalloc(pages * sizeof(*bufs), GFP_KERNEL);
 391                 counts = kmalloc(pages * sizeof(*counts), GFP_KERNEL);
 392                 offsets = kmalloc(pages * sizeof(*offsets), GFP_KERNEL);
 393                 flags = kmalloc(pages * sizeof(*flags), GFP_KERNEL);
 394                 if (!bufs || !counts || !offsets || !flags) {
 395                         CERROR("no memory for %d BRW per-page data\n", pages);
 396                         err = -ENOMEM;
 397                         GOTO(brw_free, err);
 398                 }
 399
 400                 obdos[0] = &data->ioc_obdo1;
 401                 if (num > 1)
 402                         obdos[1] = &data->ioc_obdo2;
 403
 404                 for (i = 0, pages = 0; i < num; i++) {
 405                         unsigned long off;
 406                         void *from;
 407
 408                         conns[i].oc_id = (&data->ioc_conn1)[i];
 409                         conns[i].oc_dev = obd;
 410
 411                         from = (&data->ioc_pbuf1)[i];
 412                         off = data->ioc_offset;
 413
 414                         for (j = 0; j < oa_bufs[i];
 415                              j++, pages++, off += PAGE_SIZE, from += PAGE_SIZE){
 416                                 unsigned long to;
 417
 418                                 to = __get_free_pages(GFP_KERNEL, 0);
 419                                 if (!to) {
 420                                 /*      ||
 421                                     copy_from_user((void *)to,from,PAGE_SIZE))
 422                                         free_pages(to, 0);
 423                                  */
 424                                         CERROR("no memory for brw pages\n");
 425                                         err = -ENOMEM;
 426                                         GOTO(brw_cleanup, err);
 427                                 }
 428                                 bufs[pages] = virt_to_page(to);
 429                                 counts[pages] = PAGE_SIZE;
 430                                 offsets[pages] = off;
 431                                 flags[pages] = 0;
 432                         }
 433                 }
 434
 435                 err = obd_brw(rw, conns, num, obdos, oa_bufs, bufs,
 436                               counts, offsets, flags);
 437
 438                 EXIT;
 439         brw_cleanup:
 440                 while (pages-- > 0)
 441                         free_pages((unsigned long)page_address(bufs[pages]), 0);
 442         brw_free:
 443                 kfree(flags);
 444                 kfree(offsets);
 445                 kfree(counts);
 446                 kfree(bufs);
 447                 return err;
 448         }
 449         default: {
 450                 conn.oc_id = data->ioc_conn1;
 451                 conn.oc_dev = obd;
 452
 453                 err = obd_iocontrol(cmd, &conn, sizeof(*data), data, NULL);
 454                 if (err)
 455                         RETURN(err);
 456
 457                 err = copy_to_user((int *)arg, data, sizeof(*data));
 458                 RETURN(err);
 459         }
 460         }
 461 } /* obd_class_ioctl */
 462
 463
 464 /* Driver interface done, utility functions follow */
 465 int obd_register_type(struct obd_ops *ops, char *nm)
 466 {
 467         struct obd_type *type;
 468
 469         ENTRY;
 470
 471         if (obd_init_magic != 0x11223344) {
 472                 CERROR("bad magic for type\n");
 473                 RETURN(-EINVAL);
 474         }
 475
 476         if  ( obd_nm_to_type(nm) ) {
 477                 CDEBUG(D_IOCTL, "Type %s already registered\n", nm);
 478                 RETURN(-EEXIST);
 479         }
 480
 481         OBD_ALLOC(type, sizeof(*type));
 482         if (!type)
 483                 RETURN(-ENOMEM);
 484         INIT_LIST_HEAD(&type->typ_chain);
 485         MOD_INC_USE_COUNT;
 486         list_add(&type->typ_chain, obd_types.next);
 487         type->typ_ops = ops;
 488         type->typ_name = nm;
 489         RETURN(0);
 490 }
 491
 492 int obd_unregister_type(char *nm)
 493 {
 494         struct obd_type *type = obd_nm_to_type(nm);
 495
 496         ENTRY;
 497
 498         if ( !type ) {
 499                 MOD_DEC_USE_COUNT;
 500                 CERROR("unknown obd type\n");
 501                 RETURN(-EINVAL);
 502         }
 503
 504         if ( type->typ_refcnt ) {
 505                 MOD_DEC_USE_COUNT;
 506                 CERROR("type %s has refcount (%d)\n", nm, type->typ_refcnt);
 507                 RETURN(-EBUSY);
 508         }
 509
 510         list_del(&type->typ_chain);
 511         OBD_FREE(type, sizeof(*type));
 512         MOD_DEC_USE_COUNT;
 513         RETURN(0);
 514 } /* obd_unregister_type */
 515
 516 /* declare character device */
 517 static struct file_operations obd_psdev_fops = {
 518         ioctl: obd_class_ioctl,       /* ioctl */
 519         open: obd_class_open,        /* open */
 520         release: obd_class_release,     /* release */
 521 };
 522
 523 /* modules setup */
 524 #define OBD_MINOR 241
 525 static struct miscdevice obd_psdev = {
 526         OBD_MINOR,
 527         "obd_psdev",
 528         &obd_psdev_fops
 529 };
 530
 531 EXPORT_SYMBOL(obd_register_type);
 532 EXPORT_SYMBOL(obd_unregister_type);
 533
 534 EXPORT_SYMBOL(obd_dev);
 535
 536 EXPORT_SYMBOL(gen_connect);
 537 EXPORT_SYMBOL(gen_client);
 538 EXPORT_SYMBOL(gen_cleanup);
 539 EXPORT_SYMBOL(gen_disconnect);
 540 EXPORT_SYMBOL(gen_copy_data);
 541 EXPORT_SYMBOL(obdo_cachep);
 542
 543 /* EXPORT_SYMBOL(gen_multi_attach); */
 544 EXPORT_SYMBOL(gen_multi_setup);
 545 EXPORT_SYMBOL(gen_multi_cleanup);
 546 EXPORT_SYMBOL(obd_memory);
 547 EXPORT_SYMBOL(obd_fail_loc);
 548
 549 static int __init init_obdclass(void)
 550 {
 551         int err;
 552         int i;
 553
 554         printk(KERN_INFO "OBD class driver  v0.01, braam@stelias.com\n");
 555
 556         INIT_LIST_HEAD(&obd_types);
 557
 558         if ((err = misc_register(&obd_psdev))) {
 559                 CERROR("cannot register %d err %d\n", OBD_MINOR, err);
 560                 return err;
 561         }
 562
 563         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 564                 memset(&(obd_dev[i]), 0, sizeof(obd_dev[i]));
 565                 obd_dev[i].obd_minor = i;
 566                 INIT_LIST_HEAD(&obd_dev[i].obd_gen_clients);
 567                 INIT_LIST_HEAD(&obd_dev[i].obd_req_list);
 568                 init_waitqueue_head(&obd_dev[i].obd_req_waitq);
 569         }
 570
 571         err = obd_init_obdo_cache();
 572         if (err)
 573                 return err;
 574         obd_sysctl_init();
 575         obd_init_magic = 0x11223344;
 576         return 0;
 577 }
 578
 579 static void __exit cleanup_obdclass(void)
 580 {
 581         int i;
 582         ENTRY;
 583
 584         misc_deregister(&obd_psdev);
 585         for (i = 0; i < MAX_OBD_DEVICES; i++) {
 586                 struct obd_device *obd = &obd_dev[i];
 587                 if ( obd->obd_type &&
 588                      (obd->obd_flags & OBD_SET_UP) &&
 589                      OBT(obd) && OBP(obd, detach) ) {
 590                         /* XXX should this call generic detach otherwise? */
 591                         OBP(obd, detach)(obd);
 592                 }
 593         }
 594
 595         obd_cleanup_obdo_cache();
 596         obd_sysctl_clean();
 597         CERROR("obd memory leaked: %ld bytes\n", obd_memory);
 598         obd_init_magic = 0;
 599         EXIT;
 600 }
 601
 602 MODULE_AUTHOR("Cluster File Systems, Inc. <braam@clusterfs.com>");
 603 MODULE_DESCRIPTION("Lustre Class Driver v1.0");
 604 MODULE_LICENSE("GPL");
 605
 606 module_init(init_obdclass);
 607 module_exit(cleanup_obdclass);