fs/exofs/super.c

   1 /*
   2  * Copyright (C) 2005, 2006
   3  * Avishay Traeger (avishay@gmail.com)
   4  * Copyright (C) 2008, 2009
   5  * Boaz Harrosh <bharrosh@panasas.com>
   6  *
   7  * Copyrights for code taken from ext2:
   8  *     Copyright (C) 1992, 1993, 1994, 1995
   9  *     Remy Card (card@masi.ibp.fr)
  10  *     Laboratoire MASI - Institut Blaise Pascal
  11  *     Universite Pierre et Marie Curie (Paris VI)
  12  *     from
  13  *     linux/fs/minix/inode.c
  14  *     Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  * This file is part of exofs.
  17  *
  18  * exofs is free software; you can redistribute it and/or modify
  19  * it under the terms of the GNU General Public License as published by
  20  * the Free Software Foundation.  Since it is based on ext2, and the only
  21  * valid version of GPL for the Linux kernel is version 2, the only valid
  22  * version of GPL for exofs is version 2.
  23  *
  24  * exofs is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with exofs; if not, write to the Free Software
  31  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  32  */
  33
  34 #include <linux/string.h>
  35 #include <linux/parser.h>
  36 #include <linux/vfs.h>
  37 #include <linux/random.h>
  38 #include <linux/exportfs.h>
  39 #include <linux/slab.h>
  40
  41 #include "exofs.h"
  42
  43 #define EXOFS_DBGMSG2(M...) do {} while (0)
  44
  45 /******************************************************************************
  46  * MOUNT OPTIONS
  47  *****************************************************************************/
  48
  49 /*
  50  * struct to hold what we get from mount options
  51  */
  52 struct exofs_mountopt {
  53         bool is_osdname;
  54         const char *dev_name;
  55         uint64_t pid;
  56         int timeout;
  57 };
  58
  59 /*
  60  * exofs-specific mount-time options.
  61  */
  62 enum { Opt_name, Opt_pid, Opt_to, Opt_err };
  63
  64 /*
  65  * Our mount-time options.  These should ideally be 64-bit unsigned, but the
  66  * kernel's parsing functions do not currently support that.  32-bit should be
  67  * sufficient for most applications now.
  68  */
  69 static match_table_t tokens = {
  70         {Opt_name, "osdname=%s"},
  71         {Opt_pid, "pid=%u"},
  72         {Opt_to, "to=%u"},
  73         {Opt_err, NULL}
  74 };
  75
  76 /*
  77  * The main option parsing method.  Also makes sure that all of the mandatory
  78  * mount options were set.
  79  */
  80 static int parse_options(char *options, struct exofs_mountopt *opts)
  81 {
  82         char *p;
  83         substring_t args[MAX_OPT_ARGS];
  84         int option;
  85         bool s_pid = false;
  86
  87         EXOFS_DBGMSG("parse_options %s\n", options);
  88         /* defaults */
  89         memset(opts, 0, sizeof(*opts));
  90         opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
  91
  92         while ((p = strsep(&options, ",")) != NULL) {
  93                 int token;
  94                 char str[32];
  95
  96                 if (!*p)
  97                         continue;
  98
  99                 token = match_token(p, tokens, args);
 100                 switch (token) {
 101                 case Opt_name:
 102                         opts->dev_name = match_strdup(&args[0]);
 103                         if (unlikely(!opts->dev_name)) {
 104                                 EXOFS_ERR("Error allocating dev_name");
 105                                 return -ENOMEM;
 106                         }
 107                         opts->is_osdname = true;
 108                         break;
 109                 case Opt_pid:
 110                         if (0 == match_strlcpy(str, &args[0], sizeof(str)))
 111                                 return -EINVAL;
 112                         opts->pid = simple_strtoull(str, NULL, 0);
 113                         if (opts->pid < EXOFS_MIN_PID) {
 114                                 EXOFS_ERR("Partition ID must be >= %u",
 115                                           EXOFS_MIN_PID);
 116                                 return -EINVAL;
 117                         }
 118                         s_pid = 1;
 119                         break;
 120                 case Opt_to:
 121                         if (match_int(&args[0], &option))
 122                                 return -EINVAL;
 123                         if (option <= 0) {
 124                                 EXOFS_ERR("Timout must be > 0");
 125                                 return -EINVAL;
 126                         }
 127                         opts->timeout = option * HZ;
 128                         break;
 129                 }
 130         }
 131
 132         if (!s_pid) {
 133                 EXOFS_ERR("Need to specify the following options:\n");
 134                 EXOFS_ERR("    -o pid=pid_no_to_use\n");
 135                 return -EINVAL;
 136         }
 137
 138         return 0;
 139 }
 140
 141 /******************************************************************************
 142  * INODE CACHE
 143  *****************************************************************************/
 144
 145 /*
 146  * Our inode cache.  Isn't it pretty?
 147  */
 148 static struct kmem_cache *exofs_inode_cachep;
 149
 150 /*
 151  * Allocate an inode in the cache
 152  */
 153 static struct inode *exofs_alloc_inode(struct super_block *sb)
 154 {
 155         struct exofs_i_info *oi;
 156
 157         oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
 158         if (!oi)
 159                 return NULL;
 160
 161         oi->vfs_inode.i_version = 1;
 162         return &oi->vfs_inode;
 163 }
 164
 165 static void exofs_i_callback(struct rcu_head *head)
 166 {
 167         struct inode *inode = container_of(head, struct inode, i_rcu);
 168         INIT_LIST_HEAD(&inode->i_dentry);
 169         kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
 170 }
 171
 172 /*
 173  * Remove an inode from the cache
 174  */
 175 static void exofs_destroy_inode(struct inode *inode)
 176 {
 177         call_rcu(&inode->i_rcu, exofs_i_callback);
 178 }
 179
 180 /*
 181  * Initialize the inode
 182  */
 183 static void exofs_init_once(void *foo)
 184 {
 185         struct exofs_i_info *oi = foo;
 186
 187         inode_init_once(&oi->vfs_inode);
 188 }
 189
 190 /*
 191  * Create and initialize the inode cache
 192  */
 193 static int init_inodecache(void)
 194 {
 195         exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
 196                                 sizeof(struct exofs_i_info), 0,
 197                                 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
 198                                 exofs_init_once);
 199         if (exofs_inode_cachep == NULL)
 200                 return -ENOMEM;
 201         return 0;
 202 }
 203
 204 /*
 205  * Destroy the inode cache
 206  */
 207 static void destroy_inodecache(void)
 208 {
 209         kmem_cache_destroy(exofs_inode_cachep);
 210 }
 211
 212 /******************************************************************************
 213  * Some osd helpers
 214  *****************************************************************************/
 215 void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
 216 {
 217         osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
 218 }
 219
 220 static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
 221                     u64 offset, void *p, unsigned length)
 222 {
 223         struct osd_request *or = osd_start_request(od, GFP_KERNEL);
 224 /*      struct osd_sense_info osi = {.key = 0};*/
 225         int ret;
 226
 227         if (unlikely(!or)) {
 228                 EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
 229                 return -ENOMEM;
 230         }
 231         ret = osd_req_read_kern(or, obj, offset, p, length);
 232         if (unlikely(ret)) {
 233                 EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
 234                 goto out;
 235         }
 236
 237         ret = osd_finalize_request(or, 0, cred, NULL);
 238         if (unlikely(ret)) {
 239                 EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
 240                 goto out;
 241         }
 242
 243         ret = osd_execute_request(or);
 244         if (unlikely(ret))
 245                 EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
 246         /* osd_req_decode_sense(or, ret); */
 247
 248 out:
 249         osd_end_request(or);
 250         EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 251                       "length=0x%llx dev=%p ret=>%d\n",
 252                       _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
 253         return ret;
 254 }
 255
 256 static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
 257         EXOFS_APAGE_SB_DATA,
 258         EXOFS_ATTR_SB_STATS,
 259         sizeof(struct exofs_sb_stats));
 260
 261 static int __sbi_read_stats(struct exofs_sb_info *sbi)
 262 {
 263         struct osd_attr attrs[] = {
 264                 [0] = g_attr_sb_stats,
 265         };
 266         struct ore_io_state *ios;
 267         int ret;
 268
 269         ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 270         if (unlikely(ret)) {
 271                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 272                 return ret;
 273         }
 274
 275         ios->in_attr = attrs;
 276         ios->in_attr_len = ARRAY_SIZE(attrs);
 277
 278         ret = ore_read(ios);
 279         if (unlikely(ret)) {
 280                 EXOFS_ERR("Error reading super_block stats => %d\n", ret);
 281                 goto out;
 282         }
 283
 284         ret = extract_attr_from_ios(ios, &attrs[0]);
 285         if (ret) {
 286                 EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
 287                 goto out;
 288         }
 289         if (attrs[0].len) {
 290                 struct exofs_sb_stats *ess;
 291
 292                 if (unlikely(attrs[0].len != sizeof(*ess))) {
 293                         EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
 294                                   "size(%d) != expected(%zd)\n",
 295                                   __func__, attrs[0].len, sizeof(*ess));
 296                         goto out;
 297                 }
 298
 299                 ess = attrs[0].val_ptr;
 300                 sbi->s_nextid = le64_to_cpu(ess->s_nextid);
 301                 sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
 302         }
 303
 304 out:
 305         ore_put_io_state(ios);
 306         return ret;
 307 }
 308
 309 static void stats_done(struct ore_io_state *ios, void *p)
 310 {
 311         ore_put_io_state(ios);
 312         /* Good thanks nothing to do anymore */
 313 }
 314
 315 /* Asynchronously write the stats attribute */
 316 int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
 317 {
 318         struct osd_attr attrs[] = {
 319                 [0] = g_attr_sb_stats,
 320         };
 321         struct ore_io_state *ios;
 322         int ret;
 323
 324         ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 325         if (unlikely(ret)) {
 326                 EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 327                 return ret;
 328         }
 329
 330         sbi->s_ess.s_nextid   = cpu_to_le64(sbi->s_nextid);
 331         sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
 332         attrs[0].val_ptr = &sbi->s_ess;
 333
 334
 335         ios->done = stats_done;
 336         ios->private = sbi;
 337         ios->out_attr = attrs;
 338         ios->out_attr_len = ARRAY_SIZE(attrs);
 339
 340         ret = ore_write(ios);
 341         if (unlikely(ret)) {
 342                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
 343                 ore_put_io_state(ios);
 344         }
 345
 346         return ret;
 347 }
 348
 349 /******************************************************************************
 350  * SUPERBLOCK FUNCTIONS
 351  *****************************************************************************/
 352 static const struct super_operations exofs_sops;
 353 static const struct export_operations exofs_export_ops;
 354
 355 /*
 356  * Write the superblock to the OSD
 357  */
 358 int exofs_sync_fs(struct super_block *sb, int wait)
 359 {
 360         struct exofs_sb_info *sbi;
 361         struct exofs_fscb *fscb;
 362         struct ore_comp one_comp;
 363         struct ore_components comps;
 364         struct ore_io_state *ios;
 365         int ret = -ENOMEM;
 366
 367         fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
 368         if (unlikely(!fscb))
 369                 return -ENOMEM;
 370
 371         sbi = sb->s_fs_info;
 372
 373         /* NOTE: We no longer dirty the super_block anywhere in exofs. The
 374          * reason we write the fscb here on unmount is so we can stay backwards
 375          * compatible with fscb->s_version == 1. (What we are not compatible
 376          * with is if a new version FS crashed and then we try to mount an old
 377          * version). Otherwise the exofs_fscb is read-only from mkfs time. All
 378          * the writeable info is set in exofs_sbi_write_stats() above.
 379          */
 380
 381         exofs_init_comps(&comps, &one_comp, sbi, EXOFS_SUPER_ID);
 382
 383         ret = ore_get_io_state(&sbi->layout, &comps, &ios);
 384         if (unlikely(ret))
 385                 goto out;
 386
 387         lock_super(sb);
 388
 389         ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
 390         memset(fscb, 0, ios->length);
 391         fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
 392         fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
 393         fscb->s_magic = cpu_to_le16(sb->s_magic);
 394         fscb->s_newfs = 0;
 395         fscb->s_version = EXOFS_FSCB_VER;
 396
 397         ios->offset = 0;
 398         ios->kern_buff = fscb;
 399
 400         ret = ore_write(ios);
 401         if (unlikely(ret))
 402                 EXOFS_ERR("%s: ore_write failed.\n", __func__);
 403         else
 404                 sb->s_dirt = 0;
 405
 406
 407         unlock_super(sb);
 408 out:
 409         EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
 410         ore_put_io_state(ios);
 411         kfree(fscb);
 412         return ret;
 413 }
 414
 415 static void exofs_write_super(struct super_block *sb)
 416 {
 417         if (!(sb->s_flags & MS_RDONLY))
 418                 exofs_sync_fs(sb, 1);
 419         else
 420                 sb->s_dirt = 0;
 421 }
 422
 423 static void _exofs_print_device(const char *msg, const char *dev_path,
 424                                 struct osd_dev *od, u64 pid)
 425 {
 426         const struct osd_dev_info *odi = osduld_device_info(od);
 427
 428         printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
 429                 msg, dev_path ?: "", odi->osdname, _LLU(pid));
 430 }
 431
 432 void exofs_free_sbi(struct exofs_sb_info *sbi)
 433 {
 434         while (sbi->comps.numdevs) {
 435                 int i = --sbi->comps.numdevs;
 436                 struct osd_dev *od = sbi->comps.ods[i];
 437
 438                 if (od) {
 439                         sbi->comps.ods[i] = NULL;
 440                         osduld_put_device(od);
 441                 }
 442         }
 443         if (sbi->comps.ods != sbi->_min_one_dev)
 444                 kfree(sbi->comps.ods);
 445         kfree(sbi);
 446 }
 447
 448 /*
 449  * This function is called when the vfs is freeing the superblock.  We just
 450  * need to free our own part.
 451  */
 452 static void exofs_put_super(struct super_block *sb)
 453 {
 454         int num_pend;
 455         struct exofs_sb_info *sbi = sb->s_fs_info;
 456
 457         /* make sure there are no pending commands */
 458         for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
 459              num_pend = atomic_read(&sbi->s_curr_pending)) {
 460                 wait_queue_head_t wq;
 461
 462                 printk(KERN_NOTICE "%s: !!Pending operations in flight. "
 463                        "This is a BUG. please report to osd-dev@open-osd.org\n",
 464                        __func__);
 465                 init_waitqueue_head(&wq);
 466                 wait_event_timeout(wq,
 467                                   (atomic_read(&sbi->s_curr_pending) == 0),
 468                                   msecs_to_jiffies(100));
 469         }
 470
 471         _exofs_print_device("Unmounting", NULL, sbi->comps.ods[0],
 472                             sbi->one_comp.obj.partition);
 473
 474         bdi_destroy(&sbi->bdi);
 475         exofs_free_sbi(sbi);
 476         sb->s_fs_info = NULL;
 477 }
 478
 479 static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 480                                     struct exofs_device_table *dt)
 481 {
 482         u64 stripe_length;
 483
 484         sbi->data_map.odm_num_comps   =
 485                                 le32_to_cpu(dt->dt_data_map.cb_num_comps);
 486         sbi->data_map.odm_stripe_unit =
 487                                 le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
 488         sbi->data_map.odm_group_width =
 489                                 le32_to_cpu(dt->dt_data_map.cb_group_width);
 490         sbi->data_map.odm_group_depth =
 491                                 le32_to_cpu(dt->dt_data_map.cb_group_depth);
 492         sbi->data_map.odm_mirror_cnt  =
 493                                 le32_to_cpu(dt->dt_data_map.cb_mirror_cnt);
 494         sbi->data_map.odm_raid_algorithm  =
 495                                 le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 496
 497 /* FIXME: Only raid0 for now. if not so, do not mount */
 498         if (sbi->data_map.odm_num_comps != numdevs) {
 499                 EXOFS_ERR("odm_num_comps(%u) != numdevs(%u)\n",
 500                           sbi->data_map.odm_num_comps, numdevs);
 501                 return -EINVAL;
 502         }
 503         if (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) {
 504                 EXOFS_ERR("Only RAID_0 for now\n");
 505                 return -EINVAL;
 506         }
 507         if (0 != (numdevs % (sbi->data_map.odm_mirror_cnt + 1))) {
 508                 EXOFS_ERR("Data Map wrong, numdevs=%d mirrors=%d\n",
 509                           numdevs, sbi->data_map.odm_mirror_cnt);
 510                 return -EINVAL;
 511         }
 512
 513         if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
 514                 EXOFS_ERR("Stripe Unit(0x%llx)"
 515                           " must be Multples of PAGE_SIZE(0x%lx)\n",
 516                           _LLU(sbi->data_map.odm_stripe_unit), PAGE_SIZE);
 517                 return -EINVAL;
 518         }
 519
 520         sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
 521         sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
 522
 523         if (sbi->data_map.odm_group_width) {
 524                 sbi->layout.group_width = sbi->data_map.odm_group_width;
 525                 sbi->layout.group_depth = sbi->data_map.odm_group_depth;
 526                 if (!sbi->layout.group_depth) {
 527                         EXOFS_ERR("group_depth == 0 && group_width != 0\n");
 528                         return -EINVAL;
 529                 }
 530                 sbi->layout.group_count = sbi->data_map.odm_num_comps /
 531                                                 sbi->layout.mirrors_p1 /
 532                                                 sbi->data_map.odm_group_width;
 533         } else {
 534                 if (sbi->data_map.odm_group_depth) {
 535                         printk(KERN_NOTICE "Warning: group_depth ignored "
 536                                 "group_width == 0 && group_depth == %d\n",
 537                                 sbi->data_map.odm_group_depth);
 538                         sbi->data_map.odm_group_depth = 0;
 539                 }
 540                 sbi->layout.group_width = sbi->data_map.odm_num_comps /
 541                                                         sbi->layout.mirrors_p1;
 542                 sbi->layout.group_depth = -1;
 543                 sbi->layout.group_count = 1;
 544         }
 545
 546         stripe_length = (u64)sbi->layout.group_width * sbi->layout.stripe_unit;
 547         if (stripe_length >= (1ULL << 32)) {
 548                 EXOFS_ERR("Total Stripe length(0x%llx)"
 549                           " >= 32bit is not supported\n", _LLU(stripe_length));
 550                 return -EINVAL;
 551         }
 552
 553         EXOFS_DBGMSG("exofs: layout: "
 554                 "num_comps=%u stripe_unit=0x%x group_width=%u "
 555                 "group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
 556                 numdevs,
 557                 sbi->layout.stripe_unit,
 558                 sbi->layout.group_width,
 559                 _LLU(sbi->layout.group_depth),
 560                 sbi->layout.mirrors_p1,
 561                 sbi->data_map.odm_raid_algorithm);
 562         return 0;
 563 }
 564
 565 static unsigned __ra_pages(struct ore_layout *layout)
 566 {
 567         const unsigned _MIN_RA = 32; /* min 128K read-ahead */
 568         unsigned ra_pages = layout->group_width * layout->stripe_unit /
 569                                 PAGE_SIZE;
 570         unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
 571
 572         ra_pages *= 2; /* two stripes */
 573         if (ra_pages < _MIN_RA)
 574                 ra_pages = roundup(_MIN_RA, ra_pages / 2);
 575
 576         if (ra_pages > max_io_pages)
 577                 ra_pages = max_io_pages;
 578
 579         return ra_pages;
 580 }
 581
 582 /* @odi is valid only as long as @fscb_dev is valid */
 583 static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 584                              struct osd_dev_info *odi)
 585 {
 586         odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
 587         memcpy(odi->systemid, dt_dev->systemid, odi->systemid_len);
 588
 589         odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
 590         odi->osdname = dt_dev->osdname;
 591
 592         /* FIXME support long names. Will need a _put function */
 593         if (dt_dev->long_name_offset)
 594                 return -EINVAL;
 595
 596         /* Make sure osdname is printable!
 597          * mkexofs should give us space for a null-terminator else the
 598          * device-table is invalid.
 599          */
 600         if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
 601                 odi->osdname_len = sizeof(dt_dev->osdname) - 1;
 602         dt_dev->osdname[odi->osdname_len] = 0;
 603
 604         /* If it's all zeros something is bad we read past end-of-obj */
 605         return !(odi->systemid_len || odi->osdname_len);
 606 }
 607
 608 static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
 609                                        struct osd_dev *fscb_od,
 610                                        unsigned table_count)
 611 {
 612         struct ore_comp comp;
 613         struct exofs_device_table *dt;
 614         unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 615                                              sizeof(*dt);
 616         unsigned numdevs, i;
 617         int ret;
 618
 619         dt = kmalloc(table_bytes, GFP_KERNEL);
 620         if (unlikely(!dt)) {
 621                 EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
 622                           table_bytes);
 623                 return -ENOMEM;
 624         }
 625
 626         sbi->comps.numdevs = 0;
 627
 628         comp.obj.partition = sbi->one_comp.obj.partition;
 629         comp.obj.id = EXOFS_DEVTABLE_ID;
 630         exofs_make_credential(comp.cred, &comp.obj);
 631
 632         ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
 633                               table_bytes);
 634         if (unlikely(ret)) {
 635                 EXOFS_ERR("ERROR: reading device table\n");
 636                 goto out;
 637         }
 638
 639         numdevs = le64_to_cpu(dt->dt_num_devices);
 640         if (unlikely(!numdevs)) {
 641                 ret = -EINVAL;
 642                 goto out;
 643         }
 644         WARN_ON(table_count != numdevs);
 645
 646         ret = _read_and_match_data_map(sbi, numdevs, dt);
 647         if (unlikely(ret))
 648                 goto out;
 649
 650         if (likely(numdevs > 1)) {
 651                 unsigned size = numdevs * sizeof(sbi->comps.ods[0]);
 652
 653                 /* Twice bigger table: See exofs_init_comps() and below
 654                  * comment
 655                  */
 656                 sbi->comps.ods = kzalloc(size + size - 1, GFP_KERNEL);
 657                 if (unlikely(!sbi->comps.ods)) {
 658                         EXOFS_ERR("ERROR: faild allocating Device array[%d]\n",
 659                                   numdevs);
 660                         ret = -ENOMEM;
 661                         goto out;
 662                 }
 663         }
 664
 665         for (i = 0; i < numdevs; i++) {
 666                 struct exofs_fscb fscb;
 667                 struct osd_dev_info odi;
 668                 struct osd_dev *od;
 669
 670                 if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
 671                         EXOFS_ERR("ERROR: Read all-zeros device entry\n");
 672                         ret = -EINVAL;
 673                         goto out;
 674                 }
 675
 676                 printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
 677                        i, odi.osdname);
 678
 679                 /* On all devices the device table is identical. The user can
 680                  * specify any one of the participating devices on the command
 681                  * line. We always keep them in device-table order.
 682                  */
 683                 if (fscb_od && osduld_device_same(fscb_od, &odi)) {
 684                         sbi->comps.ods[i] = fscb_od;
 685                         ++sbi->comps.numdevs;
 686                         fscb_od = NULL;
 687                         continue;
 688                 }
 689
 690                 od = osduld_info_lookup(&odi);
 691                 if (IS_ERR(od)) {
 692                         ret = PTR_ERR(od);
 693                         EXOFS_ERR("ERROR: device requested is not found "
 694                                   "osd_name-%s =>%d\n", odi.osdname, ret);
 695                         goto out;
 696                 }
 697
 698                 sbi->comps.ods[i] = od;
 699                 ++sbi->comps.numdevs;
 700
 701                 /* Read the fscb of the other devices to make sure the FS
 702                  * partition is there.
 703                  */
 704                 ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
 705                                       sizeof(fscb));
 706                 if (unlikely(ret)) {
 707                         EXOFS_ERR("ERROR: Malformed participating device "
 708                                   "error reading fscb osd_name-%s\n",
 709                                   odi.osdname);
 710                         goto out;
 711                 }
 712
 713                 /* TODO: verify other information is correct and FS-uuid
 714                  *       matches. Benny what did you say about device table
 715                  *       generation and old devices?
 716                  */
 717         }
 718
 719 out:
 720         kfree(dt);
 721         if (likely(!ret)) {
 722                 unsigned numdevs = sbi->comps.numdevs;
 723
 724                 if (unlikely(fscb_od)) {
 725                         EXOFS_ERR("ERROR: Bad device-table container device not present\n");
 726                         osduld_put_device(fscb_od);
 727                         return -EINVAL;
 728                 }
 729                 /* exofs round-robins the device table view according to inode
 730                  * number. We hold a: twice bigger table hence inodes can point
 731                  * to any device and have a sequential view of the table
 732                  * starting at this device. See exofs_init_comps()
 733                  */
 734                 for (i = 0; i < numdevs - 1; ++i)
 735                         sbi->comps.ods[i + numdevs] = sbi->comps.ods[i];
 736         }
 737         return ret;
 738 }
 739
 740 /*
 741  * Read the superblock from the OSD and fill in the fields
 742  */
 743 static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 744 {
 745         struct inode *root;
 746         struct exofs_mountopt *opts = data;
 747         struct exofs_sb_info *sbi;      /*extended info                  */
 748         struct osd_dev *od;             /* Master device                 */
 749         struct exofs_fscb fscb;         /*on-disk superblock info        */
 750         struct ore_comp comp;
 751         unsigned table_count;
 752         int ret;
 753
 754         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 755         if (!sbi)
 756                 return -ENOMEM;
 757
 758         /* use mount options to fill superblock */
 759         if (opts->is_osdname) {
 760                 struct osd_dev_info odi = {.systemid_len = 0};
 761
 762                 odi.osdname_len = strlen(opts->dev_name);
 763                 odi.osdname = (u8 *)opts->dev_name;
 764                 od = osduld_info_lookup(&odi);
 765                 kfree(opts->dev_name);
 766                 opts->dev_name = NULL;
 767         } else {
 768                 od = osduld_path_lookup(opts->dev_name);
 769         }
 770         if (IS_ERR(od)) {
 771                 ret = -EINVAL;
 772                 goto free_sbi;
 773         }
 774
 775         /* Default layout in case we do not have a device-table */
 776         sbi->layout.stripe_unit = PAGE_SIZE;
 777         sbi->layout.mirrors_p1 = 1;
 778         sbi->layout.group_width = 1;
 779         sbi->layout.group_depth = -1;
 780         sbi->layout.group_count = 1;
 781         sbi->s_timeout = opts->timeout;
 782
 783         sbi->one_comp.obj.partition = opts->pid;
 784         sbi->one_comp.obj.id = 0;
 785         exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
 786         sbi->comps.numdevs = 1;
 787         sbi->comps.single_comp = EC_SINGLE_COMP;
 788         sbi->comps.comps = &sbi->one_comp;
 789         sbi->comps.ods = sbi->_min_one_dev;
 790
 791         /* fill in some other data by hand */
 792         memset(sb->s_id, 0, sizeof(sb->s_id));
 793         strcpy(sb->s_id, "exofs");
 794         sb->s_blocksize = EXOFS_BLKSIZE;
 795         sb->s_blocksize_bits = EXOFS_BLKSHIFT;
 796         sb->s_maxbytes = MAX_LFS_FILESIZE;
 797         atomic_set(&sbi->s_curr_pending, 0);
 798         sb->s_bdev = NULL;
 799         sb->s_dev = 0;
 800
 801         comp.obj.partition = sbi->one_comp.obj.partition;
 802         comp.obj.id = EXOFS_SUPER_ID;
 803         exofs_make_credential(comp.cred, &comp.obj);
 804
 805         ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
 806         if (unlikely(ret))
 807                 goto free_sbi;
 808
 809         sb->s_magic = le16_to_cpu(fscb.s_magic);
 810         /* NOTE: we read below to be backward compatible with old versions */
 811         sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
 812         sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
 813
 814         /* make sure what we read from the object store is correct */
 815         if (sb->s_magic != EXOFS_SUPER_MAGIC) {
 816                 if (!silent)
 817                         EXOFS_ERR("ERROR: Bad magic value\n");
 818                 ret = -EINVAL;
 819                 goto free_sbi;
 820         }
 821         if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
 822                 EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
 823                           EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
 824                 ret = -EINVAL;
 825                 goto free_sbi;
 826         }
 827
 828         /* start generation numbers from a random point */
 829         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 830         spin_lock_init(&sbi->s_next_gen_lock);
 831
 832         table_count = le64_to_cpu(fscb.s_dev_table_count);
 833         if (table_count) {
 834                 ret = exofs_read_lookup_dev_table(sbi, od, table_count);
 835                 if (unlikely(ret))
 836                         goto free_sbi;
 837         } else {
 838                 sbi->comps.ods[0] = od;
 839         }
 840
 841         __sbi_read_stats(sbi);
 842
 843         /* set up operation vectors */
 844         sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
 845         sb->s_bdi = &sbi->bdi;
 846         sb->s_fs_info = sbi;
 847         sb->s_op = &exofs_sops;
 848         sb->s_export_op = &exofs_export_ops;
 849         root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
 850         if (IS_ERR(root)) {
 851                 EXOFS_ERR("ERROR: exofs_iget failed\n");
 852                 ret = PTR_ERR(root);
 853                 goto free_sbi;
 854         }
 855         sb->s_root = d_alloc_root(root);
 856         if (!sb->s_root) {
 857                 iput(root);
 858                 EXOFS_ERR("ERROR: get root inode failed\n");
 859                 ret = -ENOMEM;
 860                 goto free_sbi;
 861         }
 862
 863         if (!S_ISDIR(root->i_mode)) {
 864                 dput(sb->s_root);
 865                 sb->s_root = NULL;
 866                 EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
 867                        root->i_mode);
 868                 ret = -EINVAL;
 869                 goto free_sbi;
 870         }
 871
 872         ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
 873         if (ret) {
 874                 EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
 875                 goto free_sbi;
 876         }
 877
 878         _exofs_print_device("Mounting", opts->dev_name, sbi->comps.ods[0],
 879                             sbi->one_comp.obj.partition);
 880         return 0;
 881
 882 free_sbi:
 883         EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
 884                   opts->dev_name, sbi->one_comp.obj.partition, ret);
 885         exofs_free_sbi(sbi);
 886         return ret;
 887 }
 888
 889 /*
 890  * Set up the superblock (calls exofs_fill_super eventually)
 891  */
 892 static struct dentry *exofs_mount(struct file_system_type *type,
 893                           int flags, const char *dev_name,
 894                           void *data)
 895 {
 896         struct exofs_mountopt opts;
 897         int ret;
 898
 899         ret = parse_options(data, &opts);
 900         if (ret)
 901                 return ERR_PTR(ret);
 902
 903         if (!opts.dev_name)
 904                 opts.dev_name = dev_name;
 905         return mount_nodev(type, flags, &opts, exofs_fill_super);
 906 }
 907
 908 /*
 909  * Return information about the file system state in the buffer.  This is used
 910  * by the 'df' command, for example.
 911  */
 912 static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 913 {
 914         struct super_block *sb = dentry->d_sb;
 915         struct exofs_sb_info *sbi = sb->s_fs_info;
 916         struct ore_io_state *ios;
 917         struct osd_attr attrs[] = {
 918                 ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 919                         OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
 920                 ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
 921                         OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
 922         };
 923         uint64_t capacity = ULLONG_MAX;
 924         uint64_t used = ULLONG_MAX;
 925         int ret;
 926
 927         ret = ore_get_io_state(&sbi->layout, &sbi->comps, &ios);
 928         if (ret) {
 929                 EXOFS_DBGMSG("ore_get_io_state failed.\n");
 930                 return ret;
 931         }
 932
 933         ios->in_attr = attrs;
 934         ios->in_attr_len = ARRAY_SIZE(attrs);
 935
 936         ret = ore_read(ios);
 937         if (unlikely(ret))
 938                 goto out;
 939
 940         ret = extract_attr_from_ios(ios, &attrs[0]);
 941         if (likely(!ret)) {
 942                 capacity = get_unaligned_be64(attrs[0].val_ptr);
 943                 if (unlikely(!capacity))
 944                         capacity = ULLONG_MAX;
 945         } else
 946                 EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
 947
 948         ret = extract_attr_from_ios(ios, &attrs[1]);
 949         if (likely(!ret))
 950                 used = get_unaligned_be64(attrs[1].val_ptr);
 951         else
 952                 EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
 953
 954         /* fill in the stats buffer */
 955         buf->f_type = EXOFS_SUPER_MAGIC;
 956         buf->f_bsize = EXOFS_BLKSIZE;
 957         buf->f_blocks = capacity >> 9;
 958         buf->f_bfree = (capacity - used) >> 9;
 959         buf->f_bavail = buf->f_bfree;
 960         buf->f_files = sbi->s_numfiles;
 961         buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
 962         buf->f_namelen = EXOFS_NAME_LEN;
 963
 964 out:
 965         ore_put_io_state(ios);
 966         return ret;
 967 }
 968
 969 static const struct super_operations exofs_sops = {
 970         .alloc_inode    = exofs_alloc_inode,
 971         .destroy_inode  = exofs_destroy_inode,
 972         .write_inode    = exofs_write_inode,
 973         .evict_inode    = exofs_evict_inode,
 974         .put_super      = exofs_put_super,
 975         .write_super    = exofs_write_super,
 976         .sync_fs        = exofs_sync_fs,
 977         .statfs         = exofs_statfs,
 978 };
 979
 980 /******************************************************************************
 981  * EXPORT OPERATIONS
 982  *****************************************************************************/
 983
 984 struct dentry *exofs_get_parent(struct dentry *child)
 985 {
 986         unsigned long ino = exofs_parent_ino(child);
 987
 988         if (!ino)
 989                 return ERR_PTR(-ESTALE);
 990
 991         return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
 992 }
 993
 994 static struct inode *exofs_nfs_get_inode(struct super_block *sb,
 995                 u64 ino, u32 generation)
 996 {
 997         struct inode *inode;
 998
 999         inode = exofs_iget(sb, ino);
1000         if (IS_ERR(inode))
1001                 return ERR_CAST(inode);
1002         if (generation && inode->i_generation != generation) {
1003                 /* we didn't find the right inode.. */
1004                 iput(inode);
1005                 return ERR_PTR(-ESTALE);
1006         }
1007         return inode;
1008 }
1009
1010 static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
1011                                 struct fid *fid, int fh_len, int fh_type)
1012 {
1013         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1014                                     exofs_nfs_get_inode);
1015 }
1016
1017 static struct dentry *exofs_fh_to_parent(struct super_block *sb,
1018                                 struct fid *fid, int fh_len, int fh_type)
1019 {
1020         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1021                                     exofs_nfs_get_inode);
1022 }
1023
1024 static const struct export_operations exofs_export_ops = {
1025         .fh_to_dentry = exofs_fh_to_dentry,
1026         .fh_to_parent = exofs_fh_to_parent,
1027         .get_parent = exofs_get_parent,
1028 };
1029
1030 /******************************************************************************
1031  * INSMOD/RMMOD
1032  *****************************************************************************/
1033
1034 /*
1035  * struct that describes this file system
1036  */
1037 static struct file_system_type exofs_type = {
1038         .owner          = THIS_MODULE,
1039         .name           = "exofs",
1040         .mount          = exofs_mount,
1041         .kill_sb        = generic_shutdown_super,
1042 };
1043
1044 static int __init init_exofs(void)
1045 {
1046         int err;
1047
1048         err = init_inodecache();
1049         if (err)
1050                 goto out;
1051
1052         err = register_filesystem(&exofs_type);
1053         if (err)
1054                 goto out_d;
1055
1056         return 0;
1057 out_d:
1058         destroy_inodecache();
1059 out:
1060         return err;
1061 }
1062
1063 static void __exit exit_exofs(void)
1064 {
1065         unregister_filesystem(&exofs_type);
1066         destroy_inodecache();
1067 }
1068
1069 MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1070 MODULE_DESCRIPTION("exofs");
1071 MODULE_LICENSE("GPL");
1072
1073 module_init(init_exofs)
1074 module_exit(exit_exofs)