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/smp_lock.h>
  35 #include <linux/string.h>
  36 #include <linux/parser.h>
  37 #include <linux/vfs.h>
  38 #include <linux/random.h>
  39 #include <linux/exportfs.h>
  40 #include <linux/slab.h>
  41
  42 #include "exofs.h"
  43
  44 /******************************************************************************
  45  * MOUNT OPTIONS
  46  *****************************************************************************/
  47
  48 /*
  49  * struct to hold what we get from mount options
  50  */
  51 struct exofs_mountopt {
  52         const char *dev_name;
  53         uint64_t pid;
  54         int timeout;
  55 };
  56
  57 /*
  58  * exofs-specific mount-time options.
  59  */
  60 enum { Opt_pid, Opt_to, Opt_mkfs, Opt_format, Opt_err };
  61
  62 /*
  63  * Our mount-time options.  These should ideally be 64-bit unsigned, but the
  64  * kernel's parsing functions do not currently support that.  32-bit should be
  65  * sufficient for most applications now.
  66  */
  67 static match_table_t tokens = {
  68         {Opt_pid, "pid=%u"},
  69         {Opt_to, "to=%u"},
  70         {Opt_err, NULL}
  71 };
  72
  73 /*
  74  * The main option parsing method.  Also makes sure that all of the mandatory
  75  * mount options were set.
  76  */
  77 static int parse_options(char *options, struct exofs_mountopt *opts)
  78 {
  79         char *p;
  80         substring_t args[MAX_OPT_ARGS];
  81         int option;
  82         bool s_pid = false;
  83
  84         EXOFS_DBGMSG("parse_options %s\n", options);
  85         /* defaults */
  86         memset(opts, 0, sizeof(*opts));
  87         opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
  88
  89         while ((p = strsep(&options, ",")) != NULL) {
  90                 int token;
  91                 char str[32];
  92
  93                 if (!*p)
  94                         continue;
  95
  96                 token = match_token(p, tokens, args);
  97                 switch (token) {
  98                 case Opt_pid:
  99                         if (0 == match_strlcpy(str, &args[0], sizeof(str)))
 100                                 return -EINVAL;
 101                         opts->pid = simple_strtoull(str, NULL, 0);
 102                         if (opts->pid < EXOFS_MIN_PID) {
 103                                 EXOFS_ERR("Partition ID must be >= %u",
 104                                           EXOFS_MIN_PID);
 105                                 return -EINVAL;
 106                         }
 107                         s_pid = 1;
 108                         break;
 109                 case Opt_to:
 110                         if (match_int(&args[0], &option))
 111                                 return -EINVAL;
 112                         if (option <= 0) {
 113                                 EXOFS_ERR("Timout must be > 0");
 114                                 return -EINVAL;
 115                         }
 116                         opts->timeout = option * HZ;
 117                         break;
 118                 }
 119         }
 120
 121         if (!s_pid) {
 122                 EXOFS_ERR("Need to specify the following options:\n");
 123                 EXOFS_ERR("    -o pid=pid_no_to_use\n");
 124                 return -EINVAL;
 125         }
 126
 127         return 0;
 128 }
 129
 130 /******************************************************************************
 131  * INODE CACHE
 132  *****************************************************************************/
 133
 134 /*
 135  * Our inode cache.  Isn't it pretty?
 136  */
 137 static struct kmem_cache *exofs_inode_cachep;
 138
 139 /*
 140  * Allocate an inode in the cache
 141  */
 142 static struct inode *exofs_alloc_inode(struct super_block *sb)
 143 {
 144         struct exofs_i_info *oi;
 145
 146         oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
 147         if (!oi)
 148                 return NULL;
 149
 150         oi->vfs_inode.i_version = 1;
 151         return &oi->vfs_inode;
 152 }
 153
 154 /*
 155  * Remove an inode from the cache
 156  */
 157 static void exofs_destroy_inode(struct inode *inode)
 158 {
 159         kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
 160 }
 161
 162 /*
 163  * Initialize the inode
 164  */
 165 static void exofs_init_once(void *foo)
 166 {
 167         struct exofs_i_info *oi = foo;
 168
 169         inode_init_once(&oi->vfs_inode);
 170 }
 171
 172 /*
 173  * Create and initialize the inode cache
 174  */
 175 static int init_inodecache(void)
 176 {
 177         exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
 178                                 sizeof(struct exofs_i_info), 0,
 179                                 SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
 180                                 exofs_init_once);
 181         if (exofs_inode_cachep == NULL)
 182                 return -ENOMEM;
 183         return 0;
 184 }
 185
 186 /*
 187  * Destroy the inode cache
 188  */
 189 static void destroy_inodecache(void)
 190 {
 191         kmem_cache_destroy(exofs_inode_cachep);
 192 }
 193
 194 /******************************************************************************
 195  * SUPERBLOCK FUNCTIONS
 196  *****************************************************************************/
 197 static const struct super_operations exofs_sops;
 198 static const struct export_operations exofs_export_ops;
 199
 200 /*
 201  * Write the superblock to the OSD
 202  */
 203 int exofs_sync_fs(struct super_block *sb, int wait)
 204 {
 205         struct exofs_sb_info *sbi;
 206         struct exofs_fscb *fscb;
 207         struct exofs_io_state *ios;
 208         int ret = -ENOMEM;
 209
 210         lock_super(sb);
 211         sbi = sb->s_fs_info;
 212         fscb = &sbi->s_fscb;
 213
 214         ret = exofs_get_io_state(&sbi->layout, &ios);
 215         if (ret)
 216                 goto out;
 217
 218         /* Note: We only write the changing part of the fscb. .i.e upto the
 219          *       the fscb->s_dev_table_oid member. There is no read-modify-write
 220          *       here.
 221          */
 222         ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
 223         memset(fscb, 0, ios->length);
 224         fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
 225         fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
 226         fscb->s_magic = cpu_to_le16(sb->s_magic);
 227         fscb->s_newfs = 0;
 228         fscb->s_version = EXOFS_FSCB_VER;
 229
 230         ios->obj.id = EXOFS_SUPER_ID;
 231         ios->offset = 0;
 232         ios->kern_buff = fscb;
 233         ios->cred = sbi->s_cred;
 234
 235         ret = exofs_sbi_write(ios);
 236         if (unlikely(ret)) {
 237                 EXOFS_ERR("%s: exofs_sbi_write failed.\n", __func__);
 238                 goto out;
 239         }
 240         sb->s_dirt = 0;
 241
 242 out:
 243         EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
 244         exofs_put_io_state(ios);
 245         unlock_super(sb);
 246         return ret;
 247 }
 248
 249 static void exofs_write_super(struct super_block *sb)
 250 {
 251         if (!(sb->s_flags & MS_RDONLY))
 252                 exofs_sync_fs(sb, 1);
 253         else
 254                 sb->s_dirt = 0;
 255 }
 256
 257 static void _exofs_print_device(const char *msg, const char *dev_path,
 258                                 struct osd_dev *od, u64 pid)
 259 {
 260         const struct osd_dev_info *odi = osduld_device_info(od);
 261
 262         printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
 263                 msg, dev_path ?: "", odi->osdname, _LLU(pid));
 264 }
 265
 266 void exofs_free_sbi(struct exofs_sb_info *sbi)
 267 {
 268         while (sbi->layout.s_numdevs) {
 269                 int i = --sbi->layout.s_numdevs;
 270                 struct osd_dev *od = sbi->layout.s_ods[i];
 271
 272                 if (od) {
 273                         sbi->layout.s_ods[i] = NULL;
 274                         osduld_put_device(od);
 275                 }
 276         }
 277         kfree(sbi);
 278 }
 279
 280 /*
 281  * This function is called when the vfs is freeing the superblock.  We just
 282  * need to free our own part.
 283  */
 284 static void exofs_put_super(struct super_block *sb)
 285 {
 286         int num_pend;
 287         struct exofs_sb_info *sbi = sb->s_fs_info;
 288
 289         if (sb->s_dirt)
 290                 exofs_write_super(sb);
 291
 292         /* make sure there are no pending commands */
 293         for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
 294              num_pend = atomic_read(&sbi->s_curr_pending)) {
 295                 wait_queue_head_t wq;
 296                 init_waitqueue_head(&wq);
 297                 wait_event_timeout(wq,
 298                                   (atomic_read(&sbi->s_curr_pending) == 0),
 299                                   msecs_to_jiffies(100));
 300         }
 301
 302         _exofs_print_device("Unmounting", NULL, sbi->layout.s_ods[0],
 303                             sbi->layout.s_pid);
 304
 305         bdi_destroy(&sbi->bdi);
 306         exofs_free_sbi(sbi);
 307         sb->s_fs_info = NULL;
 308 }
 309
 310 static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 311                                     struct exofs_device_table *dt)
 312 {
 313         u64 stripe_length;
 314
 315         sbi->data_map.odm_num_comps   =
 316                                 le32_to_cpu(dt->dt_data_map.cb_num_comps);
 317         sbi->data_map.odm_stripe_unit =
 318                                 le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
 319         sbi->data_map.odm_group_width =
 320                                 le32_to_cpu(dt->dt_data_map.cb_group_width);
 321         sbi->data_map.odm_group_depth =
 322                                 le32_to_cpu(dt->dt_data_map.cb_group_depth);
 323         sbi->data_map.odm_mirror_cnt  =
 324                                 le32_to_cpu(dt->dt_data_map.cb_mirror_cnt);
 325         sbi->data_map.odm_raid_algorithm  =
 326                                 le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 327
 328 /* FIXME: Only raid0 for now. if not so, do not mount */
 329         if (sbi->data_map.odm_num_comps != numdevs) {
 330                 EXOFS_ERR("odm_num_comps(%u) != numdevs(%u)\n",
 331                           sbi->data_map.odm_num_comps, numdevs);
 332                 return -EINVAL;
 333         }
 334         if (sbi->data_map.odm_raid_algorithm != PNFS_OSD_RAID_0) {
 335                 EXOFS_ERR("Only RAID_0 for now\n");
 336                 return -EINVAL;
 337         }
 338         if (0 != (numdevs % (sbi->data_map.odm_mirror_cnt + 1))) {
 339                 EXOFS_ERR("Data Map wrong, numdevs=%d mirrors=%d\n",
 340                           numdevs, sbi->data_map.odm_mirror_cnt);
 341                 return -EINVAL;
 342         }
 343
 344         if (0 != (sbi->data_map.odm_stripe_unit & ~PAGE_MASK)) {
 345                 EXOFS_ERR("Stripe Unit(0x%llx)"
 346                           " must be Multples of PAGE_SIZE(0x%lx)\n",
 347                           _LLU(sbi->data_map.odm_stripe_unit), PAGE_SIZE);
 348                 return -EINVAL;
 349         }
 350
 351         sbi->layout.stripe_unit = sbi->data_map.odm_stripe_unit;
 352         sbi->layout.mirrors_p1 = sbi->data_map.odm_mirror_cnt + 1;
 353
 354         if (sbi->data_map.odm_group_width) {
 355                 sbi->layout.group_width = sbi->data_map.odm_group_width;
 356                 sbi->layout.group_depth = sbi->data_map.odm_group_depth;
 357                 if (!sbi->layout.group_depth) {
 358                         EXOFS_ERR("group_depth == 0 && group_width != 0\n");
 359                         return -EINVAL;
 360                 }
 361                 sbi->layout.group_count = sbi->data_map.odm_num_comps /
 362                                                 sbi->layout.mirrors_p1 /
 363                                                 sbi->data_map.odm_group_width;
 364         } else {
 365                 if (sbi->data_map.odm_group_depth) {
 366                         printk(KERN_NOTICE "Warning: group_depth ignored "
 367                                 "group_width == 0 && group_depth == %d\n",
 368                                 sbi->data_map.odm_group_depth);
 369                         sbi->data_map.odm_group_depth = 0;
 370                 }
 371                 sbi->layout.group_width = sbi->data_map.odm_num_comps /
 372                                                         sbi->layout.mirrors_p1;
 373                 sbi->layout.group_depth = -1;
 374                 sbi->layout.group_count = 1;
 375         }
 376
 377         stripe_length = (u64)sbi->layout.group_width * sbi->layout.stripe_unit;
 378         if (stripe_length >= (1ULL << 32)) {
 379                 EXOFS_ERR("Total Stripe length(0x%llx)"
 380                           " >= 32bit is not supported\n", _LLU(stripe_length));
 381                 return -EINVAL;
 382         }
 383
 384         return 0;
 385 }
 386
 387 /* @odi is valid only as long as @fscb_dev is valid */
 388 static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 389                              struct osd_dev_info *odi)
 390 {
 391         odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
 392         memcpy(odi->systemid, dt_dev->systemid, odi->systemid_len);
 393
 394         odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
 395         odi->osdname = dt_dev->osdname;
 396
 397         /* FIXME support long names. Will need a _put function */
 398         if (dt_dev->long_name_offset)
 399                 return -EINVAL;
 400
 401         /* Make sure osdname is printable!
 402          * mkexofs should give us space for a null-terminator else the
 403          * device-table is invalid.
 404          */
 405         if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
 406                 odi->osdname_len = sizeof(dt_dev->osdname) - 1;
 407         dt_dev->osdname[odi->osdname_len] = 0;
 408
 409         /* If it's all zeros something is bad we read past end-of-obj */
 410         return !(odi->systemid_len || odi->osdname_len);
 411 }
 412
 413 static int exofs_read_lookup_dev_table(struct exofs_sb_info **psbi,
 414                                        unsigned table_count)
 415 {
 416         struct exofs_sb_info *sbi = *psbi;
 417         struct osd_dev *fscb_od;
 418         struct osd_obj_id obj = {.partition = sbi->layout.s_pid,
 419                                  .id = EXOFS_DEVTABLE_ID};
 420         struct exofs_device_table *dt;
 421         unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 422                                              sizeof(*dt);
 423         unsigned numdevs, i;
 424         int ret;
 425
 426         dt = kmalloc(table_bytes, GFP_KERNEL);
 427         if (unlikely(!dt)) {
 428                 EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
 429                           table_bytes);
 430                 return -ENOMEM;
 431         }
 432
 433         fscb_od = sbi->layout.s_ods[0];
 434         sbi->layout.s_ods[0] = NULL;
 435         sbi->layout.s_numdevs = 0;
 436         ret = exofs_read_kern(fscb_od, sbi->s_cred, &obj, 0, dt, table_bytes);
 437         if (unlikely(ret)) {
 438                 EXOFS_ERR("ERROR: reading device table\n");
 439                 goto out;
 440         }
 441
 442         numdevs = le64_to_cpu(dt->dt_num_devices);
 443         if (unlikely(!numdevs)) {
 444                 ret = -EINVAL;
 445                 goto out;
 446         }
 447         WARN_ON(table_count != numdevs);
 448
 449         ret = _read_and_match_data_map(sbi, numdevs, dt);
 450         if (unlikely(ret))
 451                 goto out;
 452
 453         if (likely(numdevs > 1)) {
 454                 unsigned size = numdevs * sizeof(sbi->layout.s_ods[0]);
 455
 456                 sbi = krealloc(sbi, sizeof(*sbi) + size, GFP_KERNEL);
 457                 if (unlikely(!sbi)) {
 458                         ret = -ENOMEM;
 459                         goto out;
 460                 }
 461                 memset(&sbi->layout.s_ods[1], 0,
 462                        size - sizeof(sbi->layout.s_ods[0]));
 463                 *psbi = sbi;
 464         }
 465
 466         for (i = 0; i < numdevs; i++) {
 467                 struct exofs_fscb fscb;
 468                 struct osd_dev_info odi;
 469                 struct osd_dev *od;
 470
 471                 if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
 472                         EXOFS_ERR("ERROR: Read all-zeros device entry\n");
 473                         ret = -EINVAL;
 474                         goto out;
 475                 }
 476
 477                 printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
 478                        i, odi.osdname);
 479
 480                 /* On all devices the device table is identical. The user can
 481                  * specify any one of the participating devices on the command
 482                  * line. We always keep them in device-table order.
 483                  */
 484                 if (fscb_od && osduld_device_same(fscb_od, &odi)) {
 485                         sbi->layout.s_ods[i] = fscb_od;
 486                         ++sbi->layout.s_numdevs;
 487                         fscb_od = NULL;
 488                         continue;
 489                 }
 490
 491                 od = osduld_info_lookup(&odi);
 492                 if (unlikely(IS_ERR(od))) {
 493                         ret = PTR_ERR(od);
 494                         EXOFS_ERR("ERROR: device requested is not found "
 495                                   "osd_name-%s =>%d\n", odi.osdname, ret);
 496                         goto out;
 497                 }
 498
 499                 sbi->layout.s_ods[i] = od;
 500                 ++sbi->layout.s_numdevs;
 501
 502                 /* Read the fscb of the other devices to make sure the FS
 503                  * partition is there.
 504                  */
 505                 ret = exofs_read_kern(od, sbi->s_cred, &obj, 0, &fscb,
 506                                       sizeof(fscb));
 507                 if (unlikely(ret)) {
 508                         EXOFS_ERR("ERROR: Malformed participating device "
 509                                   "error reading fscb osd_name-%s\n",
 510                                   odi.osdname);
 511                         goto out;
 512                 }
 513
 514                 /* TODO: verify other information is correct and FS-uuid
 515                  *       matches. Benny what did you say about device table
 516                  *       generation and old devices?
 517                  */
 518         }
 519
 520 out:
 521         kfree(dt);
 522         if (unlikely(!ret && fscb_od)) {
 523                 EXOFS_ERR(
 524                       "ERROR: Bad device-table container device not present\n");
 525                 osduld_put_device(fscb_od);
 526                 ret = -EINVAL;
 527         }
 528
 529         return ret;
 530 }
 531
 532 /*
 533  * Read the superblock from the OSD and fill in the fields
 534  */
 535 static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 536 {
 537         struct inode *root;
 538         struct exofs_mountopt *opts = data;
 539         struct exofs_sb_info *sbi;      /*extended info                  */
 540         struct osd_dev *od;             /* Master device                 */
 541         struct exofs_fscb fscb;         /*on-disk superblock info        */
 542         struct osd_obj_id obj;
 543         unsigned table_count;
 544         int ret;
 545
 546         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 547         if (!sbi)
 548                 return -ENOMEM;
 549
 550         ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
 551         if (ret)
 552                 goto free_bdi;
 553
 554         /* use mount options to fill superblock */
 555         od = osduld_path_lookup(opts->dev_name);
 556         if (IS_ERR(od)) {
 557                 ret = PTR_ERR(od);
 558                 goto free_sbi;
 559         }
 560
 561         /* Default layout in case we do not have a device-table */
 562         sbi->layout.stripe_unit = PAGE_SIZE;
 563         sbi->layout.mirrors_p1 = 1;
 564         sbi->layout.group_width = 1;
 565         sbi->layout.group_depth = -1;
 566         sbi->layout.group_count = 1;
 567         sbi->layout.s_ods[0] = od;
 568         sbi->layout.s_numdevs = 1;
 569         sbi->layout.s_pid = opts->pid;
 570         sbi->s_timeout = opts->timeout;
 571
 572         /* fill in some other data by hand */
 573         memset(sb->s_id, 0, sizeof(sb->s_id));
 574         strcpy(sb->s_id, "exofs");
 575         sb->s_blocksize = EXOFS_BLKSIZE;
 576         sb->s_blocksize_bits = EXOFS_BLKSHIFT;
 577         sb->s_maxbytes = MAX_LFS_FILESIZE;
 578         atomic_set(&sbi->s_curr_pending, 0);
 579         sb->s_bdev = NULL;
 580         sb->s_dev = 0;
 581
 582         obj.partition = sbi->layout.s_pid;
 583         obj.id = EXOFS_SUPER_ID;
 584         exofs_make_credential(sbi->s_cred, &obj);
 585
 586         ret = exofs_read_kern(od, sbi->s_cred, &obj, 0, &fscb, sizeof(fscb));
 587         if (unlikely(ret))
 588                 goto free_sbi;
 589
 590         sb->s_magic = le16_to_cpu(fscb.s_magic);
 591         sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
 592         sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
 593
 594         /* make sure what we read from the object store is correct */
 595         if (sb->s_magic != EXOFS_SUPER_MAGIC) {
 596                 if (!silent)
 597                         EXOFS_ERR("ERROR: Bad magic value\n");
 598                 ret = -EINVAL;
 599                 goto free_sbi;
 600         }
 601         if (le32_to_cpu(fscb.s_version) != EXOFS_FSCB_VER) {
 602                 EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
 603                           EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
 604                 ret = -EINVAL;
 605                 goto free_sbi;
 606         }
 607
 608         /* start generation numbers from a random point */
 609         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 610         spin_lock_init(&sbi->s_next_gen_lock);
 611
 612         table_count = le64_to_cpu(fscb.s_dev_table_count);
 613         if (table_count) {
 614                 ret = exofs_read_lookup_dev_table(&sbi, table_count);
 615                 if (unlikely(ret))
 616                         goto free_sbi;
 617         }
 618
 619         /* set up operation vectors */
 620         sb->s_bdi = &sbi->bdi;
 621         sb->s_fs_info = sbi;
 622         sb->s_op = &exofs_sops;
 623         sb->s_export_op = &exofs_export_ops;
 624         root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
 625         if (IS_ERR(root)) {
 626                 EXOFS_ERR("ERROR: exofs_iget failed\n");
 627                 ret = PTR_ERR(root);
 628                 goto free_sbi;
 629         }
 630         sb->s_root = d_alloc_root(root);
 631         if (!sb->s_root) {
 632                 iput(root);
 633                 EXOFS_ERR("ERROR: get root inode failed\n");
 634                 ret = -ENOMEM;
 635                 goto free_sbi;
 636         }
 637
 638         if (!S_ISDIR(root->i_mode)) {
 639                 dput(sb->s_root);
 640                 sb->s_root = NULL;
 641                 EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
 642                        root->i_mode);
 643                 ret = -EINVAL;
 644                 goto free_sbi;
 645         }
 646
 647         _exofs_print_device("Mounting", opts->dev_name, sbi->layout.s_ods[0],
 648                             sbi->layout.s_pid);
 649         return 0;
 650
 651 free_sbi:
 652         bdi_destroy(&sbi->bdi);
 653 free_bdi:
 654         EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
 655                   opts->dev_name, sbi->layout.s_pid, ret);
 656         exofs_free_sbi(sbi);
 657         return ret;
 658 }
 659
 660 /*
 661  * Set up the superblock (calls exofs_fill_super eventually)
 662  */
 663 static int exofs_get_sb(struct file_system_type *type,
 664                           int flags, const char *dev_name,
 665                           void *data, struct vfsmount *mnt)
 666 {
 667         struct exofs_mountopt opts;
 668         int ret;
 669
 670         ret = parse_options(data, &opts);
 671         if (ret)
 672                 return ret;
 673
 674         opts.dev_name = dev_name;
 675         return get_sb_nodev(type, flags, &opts, exofs_fill_super, mnt);
 676 }
 677
 678 /*
 679  * Return information about the file system state in the buffer.  This is used
 680  * by the 'df' command, for example.
 681  */
 682 static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 683 {
 684         struct super_block *sb = dentry->d_sb;
 685         struct exofs_sb_info *sbi = sb->s_fs_info;
 686         struct exofs_io_state *ios;
 687         struct osd_attr attrs[] = {
 688                 ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 689                         OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
 690                 ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
 691                         OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
 692         };
 693         uint64_t capacity = ULLONG_MAX;
 694         uint64_t used = ULLONG_MAX;
 695         uint8_t cred_a[OSD_CAP_LEN];
 696         int ret;
 697
 698         ret = exofs_get_io_state(&sbi->layout, &ios);
 699         if (ret) {
 700                 EXOFS_DBGMSG("exofs_get_io_state failed.\n");
 701                 return ret;
 702         }
 703
 704         exofs_make_credential(cred_a, &ios->obj);
 705         ios->cred = sbi->s_cred;
 706         ios->in_attr = attrs;
 707         ios->in_attr_len = ARRAY_SIZE(attrs);
 708
 709         ret = exofs_sbi_read(ios);
 710         if (unlikely(ret))
 711                 goto out;
 712
 713         ret = extract_attr_from_ios(ios, &attrs[0]);
 714         if (likely(!ret)) {
 715                 capacity = get_unaligned_be64(attrs[0].val_ptr);
 716                 if (unlikely(!capacity))
 717                         capacity = ULLONG_MAX;
 718         } else
 719                 EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
 720
 721         ret = extract_attr_from_ios(ios, &attrs[1]);
 722         if (likely(!ret))
 723                 used = get_unaligned_be64(attrs[1].val_ptr);
 724         else
 725                 EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
 726
 727         /* fill in the stats buffer */
 728         buf->f_type = EXOFS_SUPER_MAGIC;
 729         buf->f_bsize = EXOFS_BLKSIZE;
 730         buf->f_blocks = capacity >> 9;
 731         buf->f_bfree = (capacity - used) >> 9;
 732         buf->f_bavail = buf->f_bfree;
 733         buf->f_files = sbi->s_numfiles;
 734         buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
 735         buf->f_namelen = EXOFS_NAME_LEN;
 736
 737 out:
 738         exofs_put_io_state(ios);
 739         return ret;
 740 }
 741
 742 static const struct super_operations exofs_sops = {
 743         .alloc_inode    = exofs_alloc_inode,
 744         .destroy_inode  = exofs_destroy_inode,
 745         .write_inode    = exofs_write_inode,
 746         .delete_inode   = exofs_delete_inode,
 747         .put_super      = exofs_put_super,
 748         .write_super    = exofs_write_super,
 749         .sync_fs        = exofs_sync_fs,
 750         .statfs         = exofs_statfs,
 751 };
 752
 753 /******************************************************************************
 754  * EXPORT OPERATIONS
 755  *****************************************************************************/
 756
 757 struct dentry *exofs_get_parent(struct dentry *child)
 758 {
 759         unsigned long ino = exofs_parent_ino(child);
 760
 761         if (!ino)
 762                 return NULL;
 763
 764         return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
 765 }
 766
 767 static struct inode *exofs_nfs_get_inode(struct super_block *sb,
 768                 u64 ino, u32 generation)
 769 {
 770         struct inode *inode;
 771
 772         inode = exofs_iget(sb, ino);
 773         if (IS_ERR(inode))
 774                 return ERR_CAST(inode);
 775         if (generation && inode->i_generation != generation) {
 776                 /* we didn't find the right inode.. */
 777                 iput(inode);
 778                 return ERR_PTR(-ESTALE);
 779         }
 780         return inode;
 781 }
 782
 783 static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
 784                                 struct fid *fid, int fh_len, int fh_type)
 785 {
 786         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 787                                     exofs_nfs_get_inode);
 788 }
 789
 790 static struct dentry *exofs_fh_to_parent(struct super_block *sb,
 791                                 struct fid *fid, int fh_len, int fh_type)
 792 {
 793         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 794                                     exofs_nfs_get_inode);
 795 }
 796
 797 static const struct export_operations exofs_export_ops = {
 798         .fh_to_dentry = exofs_fh_to_dentry,
 799         .fh_to_parent = exofs_fh_to_parent,
 800         .get_parent = exofs_get_parent,
 801 };
 802
 803 /******************************************************************************
 804  * INSMOD/RMMOD
 805  *****************************************************************************/
 806
 807 /*
 808  * struct that describes this file system
 809  */
 810 static struct file_system_type exofs_type = {
 811         .owner          = THIS_MODULE,
 812         .name           = "exofs",
 813         .get_sb         = exofs_get_sb,
 814         .kill_sb        = generic_shutdown_super,
 815 };
 816
 817 static int __init init_exofs(void)
 818 {
 819         int err;
 820
 821         err = init_inodecache();
 822         if (err)
 823                 goto out;
 824
 825         err = register_filesystem(&exofs_type);
 826         if (err)
 827                 goto out_d;
 828
 829         return 0;
 830 out_d:
 831         destroy_inodecache();
 832 out:
 833         return err;
 834 }
 835
 836 static void __exit exit_exofs(void)
 837 {
 838         unregister_filesystem(&exofs_type);
 839         destroy_inodecache();
 840 }
 841
 842 MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
 843 MODULE_DESCRIPTION("exofs");
 844 MODULE_LICENSE("GPL");
 845
 846 module_init(init_exofs)
 847 module_exit(exit_exofs)