linux/fs/exofs/super.c
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   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/module.h>
  39#include <linux/exportfs.h>
  40#include <linux/slab.h>
  41
  42#include "exofs.h"
  43
  44#define EXOFS_DBGMSG2(M...) do {} while (0)
  45
  46/******************************************************************************
  47 * MOUNT OPTIONS
  48 *****************************************************************************/
  49
  50/*
  51 * struct to hold what we get from mount options
  52 */
  53struct exofs_mountopt {
  54        bool is_osdname;
  55        const char *dev_name;
  56        uint64_t pid;
  57        int timeout;
  58};
  59
  60/*
  61 * exofs-specific mount-time options.
  62 */
  63enum { Opt_name, Opt_pid, Opt_to, Opt_err };
  64
  65/*
  66 * Our mount-time options.  These should ideally be 64-bit unsigned, but the
  67 * kernel's parsing functions do not currently support that.  32-bit should be
  68 * sufficient for most applications now.
  69 */
  70static match_table_t tokens = {
  71        {Opt_name, "osdname=%s"},
  72        {Opt_pid, "pid=%u"},
  73        {Opt_to, "to=%u"},
  74        {Opt_err, NULL}
  75};
  76
  77/*
  78 * The main option parsing method.  Also makes sure that all of the mandatory
  79 * mount options were set.
  80 */
  81static int parse_options(char *options, struct exofs_mountopt *opts)
  82{
  83        char *p;
  84        substring_t args[MAX_OPT_ARGS];
  85        int option;
  86        bool s_pid = false;
  87
  88        EXOFS_DBGMSG("parse_options %s\n", options);
  89        /* defaults */
  90        memset(opts, 0, sizeof(*opts));
  91        opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
  92
  93        while ((p = strsep(&options, ",")) != NULL) {
  94                int token;
  95                char str[32];
  96
  97                if (!*p)
  98                        continue;
  99
 100                token = match_token(p, tokens, args);
 101                switch (token) {
 102                case Opt_name:
 103                        opts->dev_name = match_strdup(&args[0]);
 104                        if (unlikely(!opts->dev_name)) {
 105                                EXOFS_ERR("Error allocating dev_name");
 106                                return -ENOMEM;
 107                        }
 108                        opts->is_osdname = true;
 109                        break;
 110                case Opt_pid:
 111                        if (0 == match_strlcpy(str, &args[0], sizeof(str)))
 112                                return -EINVAL;
 113                        opts->pid = simple_strtoull(str, NULL, 0);
 114                        if (opts->pid < EXOFS_MIN_PID) {
 115                                EXOFS_ERR("Partition ID must be >= %u",
 116                                          EXOFS_MIN_PID);
 117                                return -EINVAL;
 118                        }
 119                        s_pid = 1;
 120                        break;
 121                case Opt_to:
 122                        if (match_int(&args[0], &option))
 123                                return -EINVAL;
 124                        if (option <= 0) {
 125                                EXOFS_ERR("Timout must be > 0");
 126                                return -EINVAL;
 127                        }
 128                        opts->timeout = option * HZ;
 129                        break;
 130                }
 131        }
 132
 133        if (!s_pid) {
 134                EXOFS_ERR("Need to specify the following options:\n");
 135                EXOFS_ERR("    -o pid=pid_no_to_use\n");
 136                return -EINVAL;
 137        }
 138
 139        return 0;
 140}
 141
 142/******************************************************************************
 143 * INODE CACHE
 144 *****************************************************************************/
 145
 146/*
 147 * Our inode cache.  Isn't it pretty?
 148 */
 149static struct kmem_cache *exofs_inode_cachep;
 150
 151/*
 152 * Allocate an inode in the cache
 153 */
 154static struct inode *exofs_alloc_inode(struct super_block *sb)
 155{
 156        struct exofs_i_info *oi;
 157
 158        oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
 159        if (!oi)
 160                return NULL;
 161
 162        oi->vfs_inode.i_version = 1;
 163        return &oi->vfs_inode;
 164}
 165
 166static void exofs_i_callback(struct rcu_head *head)
 167{
 168        struct inode *inode = container_of(head, struct inode, i_rcu);
 169        kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
 170}
 171
 172/*
 173 * Remove an inode from the cache
 174 */
 175static 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 */
 183static 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 */
 193static 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 */
 207static void destroy_inodecache(void)
 208{
 209        kmem_cache_destroy(exofs_inode_cachep);
 210}
 211
 212/******************************************************************************
 213 * Some osd helpers
 214 *****************************************************************************/
 215void 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
 220static 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
 248out:
 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
 256static 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
 261static 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->oc, &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
 304out:
 305        ore_put_io_state(ios);
 306        return ret;
 307}
 308
 309static 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 */
 316int 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->oc, &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 *****************************************************************************/
 352static const struct super_operations exofs_sops;
 353static const struct export_operations exofs_export_ops;
 354
 355/*
 356 * Write the superblock to the OSD
 357 */
 358static 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 oc;
 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(&oc, &one_comp, sbi, EXOFS_SUPER_ID);
 382
 383        ret = ore_get_io_state(&sbi->layout, &oc, &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_le64(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
 404
 405        unlock_super(sb);
 406out:
 407        EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
 408        ore_put_io_state(ios);
 409        kfree(fscb);
 410        return ret;
 411}
 412
 413static void _exofs_print_device(const char *msg, const char *dev_path,
 414                                struct osd_dev *od, u64 pid)
 415{
 416        const struct osd_dev_info *odi = osduld_device_info(od);
 417
 418        printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
 419                msg, dev_path ?: "", odi->osdname, _LLU(pid));
 420}
 421
 422static void exofs_free_sbi(struct exofs_sb_info *sbi)
 423{
 424        unsigned numdevs = sbi->oc.numdevs;
 425
 426        while (numdevs) {
 427                unsigned i = --numdevs;
 428                struct osd_dev *od = ore_comp_dev(&sbi->oc, i);
 429
 430                if (od) {
 431                        ore_comp_set_dev(&sbi->oc, i, NULL);
 432                        osduld_put_device(od);
 433                }
 434        }
 435        kfree(sbi->oc.ods);
 436        kfree(sbi);
 437}
 438
 439/*
 440 * This function is called when the vfs is freeing the superblock.  We just
 441 * need to free our own part.
 442 */
 443static void exofs_put_super(struct super_block *sb)
 444{
 445        int num_pend;
 446        struct exofs_sb_info *sbi = sb->s_fs_info;
 447
 448        /* make sure there are no pending commands */
 449        for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
 450             num_pend = atomic_read(&sbi->s_curr_pending)) {
 451                wait_queue_head_t wq;
 452
 453                printk(KERN_NOTICE "%s: !!Pending operations in flight. "
 454                       "This is a BUG. please report to osd-dev@open-osd.org\n",
 455                       __func__);
 456                init_waitqueue_head(&wq);
 457                wait_event_timeout(wq,
 458                                  (atomic_read(&sbi->s_curr_pending) == 0),
 459                                  msecs_to_jiffies(100));
 460        }
 461
 462        _exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0),
 463                            sbi->one_comp.obj.partition);
 464
 465        exofs_sysfs_sb_del(sbi);
 466        bdi_destroy(&sbi->bdi);
 467        exofs_free_sbi(sbi);
 468        sb->s_fs_info = NULL;
 469}
 470
 471static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 472                                    struct exofs_device_table *dt)
 473{
 474        int ret;
 475
 476        sbi->layout.stripe_unit =
 477                                le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
 478        sbi->layout.group_width =
 479                                le32_to_cpu(dt->dt_data_map.cb_group_width);
 480        sbi->layout.group_depth =
 481                                le32_to_cpu(dt->dt_data_map.cb_group_depth);
 482        sbi->layout.mirrors_p1  =
 483                                le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
 484        sbi->layout.raid_algorithm  =
 485                                le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 486
 487        ret = ore_verify_layout(numdevs, &sbi->layout);
 488
 489        EXOFS_DBGMSG("exofs: layout: "
 490                "num_comps=%u stripe_unit=0x%x group_width=%u "
 491                "group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
 492                numdevs,
 493                sbi->layout.stripe_unit,
 494                sbi->layout.group_width,
 495                _LLU(sbi->layout.group_depth),
 496                sbi->layout.mirrors_p1,
 497                sbi->layout.raid_algorithm);
 498        return ret;
 499}
 500
 501static unsigned __ra_pages(struct ore_layout *layout)
 502{
 503        const unsigned _MIN_RA = 32; /* min 128K read-ahead */
 504        unsigned ra_pages = layout->group_width * layout->stripe_unit /
 505                                PAGE_SIZE;
 506        unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
 507
 508        ra_pages *= 2; /* two stripes */
 509        if (ra_pages < _MIN_RA)
 510                ra_pages = roundup(_MIN_RA, ra_pages / 2);
 511
 512        if (ra_pages > max_io_pages)
 513                ra_pages = max_io_pages;
 514
 515        return ra_pages;
 516}
 517
 518/* @odi is valid only as long as @fscb_dev is valid */
 519static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 520                             struct osd_dev_info *odi)
 521{
 522        odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
 523        if (likely(odi->systemid_len))
 524                memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
 525
 526        odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
 527        odi->osdname = dt_dev->osdname;
 528
 529        /* FIXME support long names. Will need a _put function */
 530        if (dt_dev->long_name_offset)
 531                return -EINVAL;
 532
 533        /* Make sure osdname is printable!
 534         * mkexofs should give us space for a null-terminator else the
 535         * device-table is invalid.
 536         */
 537        if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
 538                odi->osdname_len = sizeof(dt_dev->osdname) - 1;
 539        dt_dev->osdname[odi->osdname_len] = 0;
 540
 541        /* If it's all zeros something is bad we read past end-of-obj */
 542        return !(odi->systemid_len || odi->osdname_len);
 543}
 544
 545int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
 546                      struct exofs_dev **peds)
 547{
 548        struct __alloc_ore_devs_and_exofs_devs {
 549                /* Twice bigger table: See exofs_init_comps() and comment at
 550                 * exofs_read_lookup_dev_table()
 551                 */
 552                struct ore_dev *oreds[numdevs * 2 - 1];
 553                struct exofs_dev eds[numdevs];
 554        } *aoded;
 555        struct exofs_dev *eds;
 556        unsigned i;
 557
 558        aoded = kzalloc(sizeof(*aoded), GFP_KERNEL);
 559        if (unlikely(!aoded)) {
 560                EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
 561                          numdevs);
 562                return -ENOMEM;
 563        }
 564
 565        sbi->oc.ods = aoded->oreds;
 566        *peds = eds = aoded->eds;
 567        for (i = 0; i < numdevs; ++i)
 568                aoded->oreds[i] = &eds[i].ored;
 569        return 0;
 570}
 571
 572static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
 573                                       struct osd_dev *fscb_od,
 574                                       unsigned table_count)
 575{
 576        struct ore_comp comp;
 577        struct exofs_device_table *dt;
 578        struct exofs_dev *eds;
 579        unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 580                                             sizeof(*dt);
 581        unsigned numdevs, i;
 582        int ret;
 583
 584        dt = kmalloc(table_bytes, GFP_KERNEL);
 585        if (unlikely(!dt)) {
 586                EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
 587                          table_bytes);
 588                return -ENOMEM;
 589        }
 590
 591        sbi->oc.numdevs = 0;
 592
 593        comp.obj.partition = sbi->one_comp.obj.partition;
 594        comp.obj.id = EXOFS_DEVTABLE_ID;
 595        exofs_make_credential(comp.cred, &comp.obj);
 596
 597        ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
 598                              table_bytes);
 599        if (unlikely(ret)) {
 600                EXOFS_ERR("ERROR: reading device table\n");
 601                goto out;
 602        }
 603
 604        numdevs = le64_to_cpu(dt->dt_num_devices);
 605        if (unlikely(!numdevs)) {
 606                ret = -EINVAL;
 607                goto out;
 608        }
 609        WARN_ON(table_count != numdevs);
 610
 611        ret = _read_and_match_data_map(sbi, numdevs, dt);
 612        if (unlikely(ret))
 613                goto out;
 614
 615        ret = __alloc_dev_table(sbi, numdevs, &eds);
 616        if (unlikely(ret))
 617                goto out;
 618        /* exofs round-robins the device table view according to inode
 619         * number. We hold a: twice bigger table hence inodes can point
 620         * to any device and have a sequential view of the table
 621         * starting at this device. See exofs_init_comps()
 622         */
 623        memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0],
 624                (numdevs - 1) * sizeof(sbi->oc.ods[0]));
 625
 626        /* create sysfs subdir under which we put the device table
 627         * And cluster layout. A Superblock is identified by the string:
 628         *      "dev[0].osdname"_"pid"
 629         */
 630        exofs_sysfs_sb_add(sbi, &dt->dt_dev_table[0]);
 631
 632        for (i = 0; i < numdevs; i++) {
 633                struct exofs_fscb fscb;
 634                struct osd_dev_info odi;
 635                struct osd_dev *od;
 636
 637                if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
 638                        EXOFS_ERR("ERROR: Read all-zeros device entry\n");
 639                        ret = -EINVAL;
 640                        goto out;
 641                }
 642
 643                printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
 644                       i, odi.osdname);
 645
 646                /* the exofs id is currently the table index */
 647                eds[i].did = i;
 648
 649                /* On all devices the device table is identical. The user can
 650                 * specify any one of the participating devices on the command
 651                 * line. We always keep them in device-table order.
 652                 */
 653                if (fscb_od && osduld_device_same(fscb_od, &odi)) {
 654                        eds[i].ored.od = fscb_od;
 655                        ++sbi->oc.numdevs;
 656                        fscb_od = NULL;
 657                        exofs_sysfs_odev_add(&eds[i], sbi);
 658                        continue;
 659                }
 660
 661                od = osduld_info_lookup(&odi);
 662                if (IS_ERR(od)) {
 663                        ret = PTR_ERR(od);
 664                        EXOFS_ERR("ERROR: device requested is not found "
 665                                  "osd_name-%s =>%d\n", odi.osdname, ret);
 666                        goto out;
 667                }
 668
 669                eds[i].ored.od = od;
 670                ++sbi->oc.numdevs;
 671
 672                /* Read the fscb of the other devices to make sure the FS
 673                 * partition is there.
 674                 */
 675                ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
 676                                      sizeof(fscb));
 677                if (unlikely(ret)) {
 678                        EXOFS_ERR("ERROR: Malformed participating device "
 679                                  "error reading fscb osd_name-%s\n",
 680                                  odi.osdname);
 681                        goto out;
 682                }
 683                exofs_sysfs_odev_add(&eds[i], sbi);
 684
 685                /* TODO: verify other information is correct and FS-uuid
 686                 *       matches. Benny what did you say about device table
 687                 *       generation and old devices?
 688                 */
 689        }
 690
 691out:
 692        kfree(dt);
 693        if (unlikely(fscb_od && !ret)) {
 694                        EXOFS_ERR("ERROR: Bad device-table container device not present\n");
 695                        osduld_put_device(fscb_od);
 696                        return -EINVAL;
 697        }
 698        return ret;
 699}
 700
 701/*
 702 * Read the superblock from the OSD and fill in the fields
 703 */
 704static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 705{
 706        struct inode *root;
 707        struct exofs_mountopt *opts = data;
 708        struct exofs_sb_info *sbi;      /*extended info                  */
 709        struct osd_dev *od;             /* Master device                 */
 710        struct exofs_fscb fscb;         /*on-disk superblock info        */
 711        struct ore_comp comp;
 712        unsigned table_count;
 713        int ret;
 714
 715        sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 716        if (!sbi)
 717                return -ENOMEM;
 718
 719        /* use mount options to fill superblock */
 720        if (opts->is_osdname) {
 721                struct osd_dev_info odi = {.systemid_len = 0};
 722
 723                odi.osdname_len = strlen(opts->dev_name);
 724                odi.osdname = (u8 *)opts->dev_name;
 725                od = osduld_info_lookup(&odi);
 726                kfree(opts->dev_name);
 727                opts->dev_name = NULL;
 728        } else {
 729                od = osduld_path_lookup(opts->dev_name);
 730        }
 731        if (IS_ERR(od)) {
 732                ret = -EINVAL;
 733                goto free_sbi;
 734        }
 735
 736        /* Default layout in case we do not have a device-table */
 737        sbi->layout.stripe_unit = PAGE_SIZE;
 738        sbi->layout.mirrors_p1 = 1;
 739        sbi->layout.group_width = 1;
 740        sbi->layout.group_depth = -1;
 741        sbi->layout.group_count = 1;
 742        sbi->s_timeout = opts->timeout;
 743
 744        sbi->one_comp.obj.partition = opts->pid;
 745        sbi->one_comp.obj.id = 0;
 746        exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
 747        sbi->oc.single_comp = EC_SINGLE_COMP;
 748        sbi->oc.comps = &sbi->one_comp;
 749
 750        /* fill in some other data by hand */
 751        memset(sb->s_id, 0, sizeof(sb->s_id));
 752        strcpy(sb->s_id, "exofs");
 753        sb->s_blocksize = EXOFS_BLKSIZE;
 754        sb->s_blocksize_bits = EXOFS_BLKSHIFT;
 755        sb->s_maxbytes = MAX_LFS_FILESIZE;
 756        sb->s_max_links = EXOFS_LINK_MAX;
 757        atomic_set(&sbi->s_curr_pending, 0);
 758        sb->s_bdev = NULL;
 759        sb->s_dev = 0;
 760
 761        comp.obj.partition = sbi->one_comp.obj.partition;
 762        comp.obj.id = EXOFS_SUPER_ID;
 763        exofs_make_credential(comp.cred, &comp.obj);
 764
 765        ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
 766        if (unlikely(ret))
 767                goto free_sbi;
 768
 769        sb->s_magic = le16_to_cpu(fscb.s_magic);
 770        /* NOTE: we read below to be backward compatible with old versions */
 771        sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
 772        sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
 773
 774        /* make sure what we read from the object store is correct */
 775        if (sb->s_magic != EXOFS_SUPER_MAGIC) {
 776                if (!silent)
 777                        EXOFS_ERR("ERROR: Bad magic value\n");
 778                ret = -EINVAL;
 779                goto free_sbi;
 780        }
 781        if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
 782                EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
 783                          EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
 784                ret = -EINVAL;
 785                goto free_sbi;
 786        }
 787
 788        /* start generation numbers from a random point */
 789        get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 790        spin_lock_init(&sbi->s_next_gen_lock);
 791
 792        table_count = le64_to_cpu(fscb.s_dev_table_count);
 793        if (table_count) {
 794                ret = exofs_read_lookup_dev_table(sbi, od, table_count);
 795                if (unlikely(ret))
 796                        goto free_sbi;
 797        } else {
 798                struct exofs_dev *eds;
 799
 800                ret = __alloc_dev_table(sbi, 1, &eds);
 801                if (unlikely(ret))
 802                        goto free_sbi;
 803
 804                ore_comp_set_dev(&sbi->oc, 0, od);
 805                sbi->oc.numdevs = 1;
 806        }
 807
 808        __sbi_read_stats(sbi);
 809
 810        /* set up operation vectors */
 811        sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
 812        sb->s_bdi = &sbi->bdi;
 813        sb->s_fs_info = sbi;
 814        sb->s_op = &exofs_sops;
 815        sb->s_export_op = &exofs_export_ops;
 816        root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
 817        if (IS_ERR(root)) {
 818                EXOFS_ERR("ERROR: exofs_iget failed\n");
 819                ret = PTR_ERR(root);
 820                goto free_sbi;
 821        }
 822        sb->s_root = d_make_root(root);
 823        if (!sb->s_root) {
 824                EXOFS_ERR("ERROR: get root inode failed\n");
 825                ret = -ENOMEM;
 826                goto free_sbi;
 827        }
 828
 829        if (!S_ISDIR(root->i_mode)) {
 830                dput(sb->s_root);
 831                sb->s_root = NULL;
 832                EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
 833                       root->i_mode);
 834                ret = -EINVAL;
 835                goto free_sbi;
 836        }
 837
 838        ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
 839        if (ret) {
 840                EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
 841                dput(sb->s_root);
 842                sb->s_root = NULL;
 843                goto free_sbi;
 844        }
 845
 846        exofs_sysfs_dbg_print();
 847        _exofs_print_device("Mounting", opts->dev_name,
 848                            ore_comp_dev(&sbi->oc, 0),
 849                            sbi->one_comp.obj.partition);
 850        return 0;
 851
 852free_sbi:
 853        EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
 854                  opts->dev_name, sbi->one_comp.obj.partition, ret);
 855        exofs_free_sbi(sbi);
 856        return ret;
 857}
 858
 859/*
 860 * Set up the superblock (calls exofs_fill_super eventually)
 861 */
 862static struct dentry *exofs_mount(struct file_system_type *type,
 863                          int flags, const char *dev_name,
 864                          void *data)
 865{
 866        struct exofs_mountopt opts;
 867        int ret;
 868
 869        ret = parse_options(data, &opts);
 870        if (ret)
 871                return ERR_PTR(ret);
 872
 873        if (!opts.dev_name)
 874                opts.dev_name = dev_name;
 875        return mount_nodev(type, flags, &opts, exofs_fill_super);
 876}
 877
 878/*
 879 * Return information about the file system state in the buffer.  This is used
 880 * by the 'df' command, for example.
 881 */
 882static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 883{
 884        struct super_block *sb = dentry->d_sb;
 885        struct exofs_sb_info *sbi = sb->s_fs_info;
 886        struct ore_io_state *ios;
 887        struct osd_attr attrs[] = {
 888                ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 889                        OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
 890                ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
 891                        OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
 892        };
 893        uint64_t capacity = ULLONG_MAX;
 894        uint64_t used = ULLONG_MAX;
 895        int ret;
 896
 897        ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
 898        if (ret) {
 899                EXOFS_DBGMSG("ore_get_io_state failed.\n");
 900                return ret;
 901        }
 902
 903        ios->in_attr = attrs;
 904        ios->in_attr_len = ARRAY_SIZE(attrs);
 905
 906        ret = ore_read(ios);
 907        if (unlikely(ret))
 908                goto out;
 909
 910        ret = extract_attr_from_ios(ios, &attrs[0]);
 911        if (likely(!ret)) {
 912                capacity = get_unaligned_be64(attrs[0].val_ptr);
 913                if (unlikely(!capacity))
 914                        capacity = ULLONG_MAX;
 915        } else
 916                EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
 917
 918        ret = extract_attr_from_ios(ios, &attrs[1]);
 919        if (likely(!ret))
 920                used = get_unaligned_be64(attrs[1].val_ptr);
 921        else
 922                EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
 923
 924        /* fill in the stats buffer */
 925        buf->f_type = EXOFS_SUPER_MAGIC;
 926        buf->f_bsize = EXOFS_BLKSIZE;
 927        buf->f_blocks = capacity >> 9;
 928        buf->f_bfree = (capacity - used) >> 9;
 929        buf->f_bavail = buf->f_bfree;
 930        buf->f_files = sbi->s_numfiles;
 931        buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
 932        buf->f_namelen = EXOFS_NAME_LEN;
 933
 934out:
 935        ore_put_io_state(ios);
 936        return ret;
 937}
 938
 939static const struct super_operations exofs_sops = {
 940        .alloc_inode    = exofs_alloc_inode,
 941        .destroy_inode  = exofs_destroy_inode,
 942        .write_inode    = exofs_write_inode,
 943        .evict_inode    = exofs_evict_inode,
 944        .put_super      = exofs_put_super,
 945        .sync_fs        = exofs_sync_fs,
 946        .statfs         = exofs_statfs,
 947};
 948
 949/******************************************************************************
 950 * EXPORT OPERATIONS
 951 *****************************************************************************/
 952
 953static struct dentry *exofs_get_parent(struct dentry *child)
 954{
 955        unsigned long ino = exofs_parent_ino(child);
 956
 957        if (!ino)
 958                return ERR_PTR(-ESTALE);
 959
 960        return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
 961}
 962
 963static struct inode *exofs_nfs_get_inode(struct super_block *sb,
 964                u64 ino, u32 generation)
 965{
 966        struct inode *inode;
 967
 968        inode = exofs_iget(sb, ino);
 969        if (IS_ERR(inode))
 970                return ERR_CAST(inode);
 971        if (generation && inode->i_generation != generation) {
 972                /* we didn't find the right inode.. */
 973                iput(inode);
 974                return ERR_PTR(-ESTALE);
 975        }
 976        return inode;
 977}
 978
 979static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
 980                                struct fid *fid, int fh_len, int fh_type)
 981{
 982        return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 983                                    exofs_nfs_get_inode);
 984}
 985
 986static struct dentry *exofs_fh_to_parent(struct super_block *sb,
 987                                struct fid *fid, int fh_len, int fh_type)
 988{
 989        return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 990                                    exofs_nfs_get_inode);
 991}
 992
 993static const struct export_operations exofs_export_ops = {
 994        .fh_to_dentry = exofs_fh_to_dentry,
 995        .fh_to_parent = exofs_fh_to_parent,
 996        .get_parent = exofs_get_parent,
 997};
 998
 999/******************************************************************************
1000 * INSMOD/RMMOD
1001 *****************************************************************************/
1002
1003/*
1004 * struct that describes this file system
1005 */
1006static struct file_system_type exofs_type = {
1007        .owner          = THIS_MODULE,
1008        .name           = "exofs",
1009        .mount          = exofs_mount,
1010        .kill_sb        = generic_shutdown_super,
1011};
1012
1013static int __init init_exofs(void)
1014{
1015        int err;
1016
1017        err = init_inodecache();
1018        if (err)
1019                goto out;
1020
1021        err = register_filesystem(&exofs_type);
1022        if (err)
1023                goto out_d;
1024
1025        /* We don't fail if sysfs creation failed */
1026        exofs_sysfs_init();
1027
1028        return 0;
1029out_d:
1030        destroy_inodecache();
1031out:
1032        return err;
1033}
1034
1035static void __exit exit_exofs(void)
1036{
1037        exofs_sysfs_uninit();
1038        unregister_filesystem(&exofs_type);
1039        destroy_inodecache();
1040}
1041
1042MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1043MODULE_DESCRIPTION("exofs");
1044MODULE_LICENSE("GPL");
1045
1046module_init(init_exofs)
1047module_exit(exit_exofs)
1048
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