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        /*
 210         * Make sure all delayed rcu free inodes are flushed before we
 211         * destroy cache.
 212         */
 213        rcu_barrier();
 214        kmem_cache_destroy(exofs_inode_cachep);
 215}
 216
 217/******************************************************************************
 218 * Some osd helpers
 219 *****************************************************************************/
 220void exofs_make_credential(u8 cred_a[OSD_CAP_LEN], const struct osd_obj_id *obj)
 221{
 222        osd_sec_init_nosec_doall_caps(cred_a, obj, false, true);
 223}
 224
 225static int exofs_read_kern(struct osd_dev *od, u8 *cred, struct osd_obj_id *obj,
 226                    u64 offset, void *p, unsigned length)
 227{
 228        struct osd_request *or = osd_start_request(od, GFP_KERNEL);
 229/*      struct osd_sense_info osi = {.key = 0};*/
 230        int ret;
 231
 232        if (unlikely(!or)) {
 233                EXOFS_DBGMSG("%s: osd_start_request failed.\n", __func__);
 234                return -ENOMEM;
 235        }
 236        ret = osd_req_read_kern(or, obj, offset, p, length);
 237        if (unlikely(ret)) {
 238                EXOFS_DBGMSG("%s: osd_req_read_kern failed.\n", __func__);
 239                goto out;
 240        }
 241
 242        ret = osd_finalize_request(or, 0, cred, NULL);
 243        if (unlikely(ret)) {
 244                EXOFS_DBGMSG("Failed to osd_finalize_request() => %d\n", ret);
 245                goto out;
 246        }
 247
 248        ret = osd_execute_request(or);
 249        if (unlikely(ret))
 250                EXOFS_DBGMSG("osd_execute_request() => %d\n", ret);
 251        /* osd_req_decode_sense(or, ret); */
 252
 253out:
 254        osd_end_request(or);
 255        EXOFS_DBGMSG2("read_kern(0x%llx) offset=0x%llx "
 256                      "length=0x%llx dev=%p ret=>%d\n",
 257                      _LLU(obj->id), _LLU(offset), _LLU(length), od, ret);
 258        return ret;
 259}
 260
 261static const struct osd_attr g_attr_sb_stats = ATTR_DEF(
 262        EXOFS_APAGE_SB_DATA,
 263        EXOFS_ATTR_SB_STATS,
 264        sizeof(struct exofs_sb_stats));
 265
 266static int __sbi_read_stats(struct exofs_sb_info *sbi)
 267{
 268        struct osd_attr attrs[] = {
 269                [0] = g_attr_sb_stats,
 270        };
 271        struct ore_io_state *ios;
 272        int ret;
 273
 274        ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
 275        if (unlikely(ret)) {
 276                EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 277                return ret;
 278        }
 279
 280        ios->in_attr = attrs;
 281        ios->in_attr_len = ARRAY_SIZE(attrs);
 282
 283        ret = ore_read(ios);
 284        if (unlikely(ret)) {
 285                EXOFS_ERR("Error reading super_block stats => %d\n", ret);
 286                goto out;
 287        }
 288
 289        ret = extract_attr_from_ios(ios, &attrs[0]);
 290        if (ret) {
 291                EXOFS_ERR("%s: extract_attr of sb_stats failed\n", __func__);
 292                goto out;
 293        }
 294        if (attrs[0].len) {
 295                struct exofs_sb_stats *ess;
 296
 297                if (unlikely(attrs[0].len != sizeof(*ess))) {
 298                        EXOFS_ERR("%s: Wrong version of exofs_sb_stats "
 299                                  "size(%d) != expected(%zd)\n",
 300                                  __func__, attrs[0].len, sizeof(*ess));
 301                        goto out;
 302                }
 303
 304                ess = attrs[0].val_ptr;
 305                sbi->s_nextid = le64_to_cpu(ess->s_nextid);
 306                sbi->s_numfiles = le32_to_cpu(ess->s_numfiles);
 307        }
 308
 309out:
 310        ore_put_io_state(ios);
 311        return ret;
 312}
 313
 314static void stats_done(struct ore_io_state *ios, void *p)
 315{
 316        ore_put_io_state(ios);
 317        /* Good thanks nothing to do anymore */
 318}
 319
 320/* Asynchronously write the stats attribute */
 321int exofs_sbi_write_stats(struct exofs_sb_info *sbi)
 322{
 323        struct osd_attr attrs[] = {
 324                [0] = g_attr_sb_stats,
 325        };
 326        struct ore_io_state *ios;
 327        int ret;
 328
 329        ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
 330        if (unlikely(ret)) {
 331                EXOFS_ERR("%s: ore_get_io_state failed.\n", __func__);
 332                return ret;
 333        }
 334
 335        sbi->s_ess.s_nextid   = cpu_to_le64(sbi->s_nextid);
 336        sbi->s_ess.s_numfiles = cpu_to_le64(sbi->s_numfiles);
 337        attrs[0].val_ptr = &sbi->s_ess;
 338
 339
 340        ios->done = stats_done;
 341        ios->private = sbi;
 342        ios->out_attr = attrs;
 343        ios->out_attr_len = ARRAY_SIZE(attrs);
 344
 345        ret = ore_write(ios);
 346        if (unlikely(ret)) {
 347                EXOFS_ERR("%s: ore_write failed.\n", __func__);
 348                ore_put_io_state(ios);
 349        }
 350
 351        return ret;
 352}
 353
 354/******************************************************************************
 355 * SUPERBLOCK FUNCTIONS
 356 *****************************************************************************/
 357static const struct super_operations exofs_sops;
 358static const struct export_operations exofs_export_ops;
 359
 360/*
 361 * Write the superblock to the OSD
 362 */
 363static int exofs_sync_fs(struct super_block *sb, int wait)
 364{
 365        struct exofs_sb_info *sbi;
 366        struct exofs_fscb *fscb;
 367        struct ore_comp one_comp;
 368        struct ore_components oc;
 369        struct ore_io_state *ios;
 370        int ret = -ENOMEM;
 371
 372        fscb = kmalloc(sizeof(*fscb), GFP_KERNEL);
 373        if (unlikely(!fscb))
 374                return -ENOMEM;
 375
 376        sbi = sb->s_fs_info;
 377
 378        /* NOTE: We no longer dirty the super_block anywhere in exofs. The
 379         * reason we write the fscb here on unmount is so we can stay backwards
 380         * compatible with fscb->s_version == 1. (What we are not compatible
 381         * with is if a new version FS crashed and then we try to mount an old
 382         * version). Otherwise the exofs_fscb is read-only from mkfs time. All
 383         * the writeable info is set in exofs_sbi_write_stats() above.
 384         */
 385
 386        exofs_init_comps(&oc, &one_comp, sbi, EXOFS_SUPER_ID);
 387
 388        ret = ore_get_io_state(&sbi->layout, &oc, &ios);
 389        if (unlikely(ret))
 390                goto out;
 391
 392        ios->length = offsetof(struct exofs_fscb, s_dev_table_oid);
 393        memset(fscb, 0, ios->length);
 394        fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
 395        fscb->s_numfiles = cpu_to_le64(sbi->s_numfiles);
 396        fscb->s_magic = cpu_to_le16(sb->s_magic);
 397        fscb->s_newfs = 0;
 398        fscb->s_version = EXOFS_FSCB_VER;
 399
 400        ios->offset = 0;
 401        ios->kern_buff = fscb;
 402
 403        ret = ore_write(ios);
 404        if (unlikely(ret))
 405                EXOFS_ERR("%s: ore_write failed.\n", __func__);
 406
 407out:
 408        EXOFS_DBGMSG("s_nextid=0x%llx ret=%d\n", _LLU(sbi->s_nextid), ret);
 409        ore_put_io_state(ios);
 410        kfree(fscb);
 411        return ret;
 412}
 413
 414static void _exofs_print_device(const char *msg, const char *dev_path,
 415                                struct osd_dev *od, u64 pid)
 416{
 417        const struct osd_dev_info *odi = osduld_device_info(od);
 418
 419        printk(KERN_NOTICE "exofs: %s %s osd_name-%s pid-0x%llx\n",
 420                msg, dev_path ?: "", odi->osdname, _LLU(pid));
 421}
 422
 423static void exofs_free_sbi(struct exofs_sb_info *sbi)
 424{
 425        unsigned numdevs = sbi->oc.numdevs;
 426
 427        while (numdevs) {
 428                unsigned i = --numdevs;
 429                struct osd_dev *od = ore_comp_dev(&sbi->oc, i);
 430
 431                if (od) {
 432                        ore_comp_set_dev(&sbi->oc, i, NULL);
 433                        osduld_put_device(od);
 434                }
 435        }
 436        kfree(sbi->oc.ods);
 437        kfree(sbi);
 438}
 439
 440/*
 441 * This function is called when the vfs is freeing the superblock.  We just
 442 * need to free our own part.
 443 */
 444static void exofs_put_super(struct super_block *sb)
 445{
 446        int num_pend;
 447        struct exofs_sb_info *sbi = sb->s_fs_info;
 448
 449        /* make sure there are no pending commands */
 450        for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
 451             num_pend = atomic_read(&sbi->s_curr_pending)) {
 452                wait_queue_head_t wq;
 453
 454                printk(KERN_NOTICE "%s: !!Pending operations in flight. "
 455                       "This is a BUG. please report to osd-dev@open-osd.org\n",
 456                       __func__);
 457                init_waitqueue_head(&wq);
 458                wait_event_timeout(wq,
 459                                  (atomic_read(&sbi->s_curr_pending) == 0),
 460                                  msecs_to_jiffies(100));
 461        }
 462
 463        _exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0),
 464                            sbi->one_comp.obj.partition);
 465
 466        exofs_sysfs_sb_del(sbi);
 467        bdi_destroy(&sbi->bdi);
 468        exofs_free_sbi(sbi);
 469        sb->s_fs_info = NULL;
 470}
 471
 472static int _read_and_match_data_map(struct exofs_sb_info *sbi, unsigned numdevs,
 473                                    struct exofs_device_table *dt)
 474{
 475        int ret;
 476
 477        sbi->layout.stripe_unit =
 478                                le64_to_cpu(dt->dt_data_map.cb_stripe_unit);
 479        sbi->layout.group_width =
 480                                le32_to_cpu(dt->dt_data_map.cb_group_width);
 481        sbi->layout.group_depth =
 482                                le32_to_cpu(dt->dt_data_map.cb_group_depth);
 483        sbi->layout.mirrors_p1  =
 484                                le32_to_cpu(dt->dt_data_map.cb_mirror_cnt) + 1;
 485        sbi->layout.raid_algorithm  =
 486                                le32_to_cpu(dt->dt_data_map.cb_raid_algorithm);
 487
 488        ret = ore_verify_layout(numdevs, &sbi->layout);
 489
 490        EXOFS_DBGMSG("exofs: layout: "
 491                "num_comps=%u stripe_unit=0x%x group_width=%u "
 492                "group_depth=0x%llx mirrors_p1=%u raid_algorithm=%u\n",
 493                numdevs,
 494                sbi->layout.stripe_unit,
 495                sbi->layout.group_width,
 496                _LLU(sbi->layout.group_depth),
 497                sbi->layout.mirrors_p1,
 498                sbi->layout.raid_algorithm);
 499        return ret;
 500}
 501
 502static unsigned __ra_pages(struct ore_layout *layout)
 503{
 504        const unsigned _MIN_RA = 32; /* min 128K read-ahead */
 505        unsigned ra_pages = layout->group_width * layout->stripe_unit /
 506                                PAGE_SIZE;
 507        unsigned max_io_pages = exofs_max_io_pages(layout, ~0);
 508
 509        ra_pages *= 2; /* two stripes */
 510        if (ra_pages < _MIN_RA)
 511                ra_pages = roundup(_MIN_RA, ra_pages / 2);
 512
 513        if (ra_pages > max_io_pages)
 514                ra_pages = max_io_pages;
 515
 516        return ra_pages;
 517}
 518
 519/* @odi is valid only as long as @fscb_dev is valid */
 520static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev,
 521                             struct osd_dev_info *odi)
 522{
 523        odi->systemid_len = le32_to_cpu(dt_dev->systemid_len);
 524        if (likely(odi->systemid_len))
 525                memcpy(odi->systemid, dt_dev->systemid, OSD_SYSTEMID_LEN);
 526
 527        odi->osdname_len = le32_to_cpu(dt_dev->osdname_len);
 528        odi->osdname = dt_dev->osdname;
 529
 530        /* FIXME support long names. Will need a _put function */
 531        if (dt_dev->long_name_offset)
 532                return -EINVAL;
 533
 534        /* Make sure osdname is printable!
 535         * mkexofs should give us space for a null-terminator else the
 536         * device-table is invalid.
 537         */
 538        if (unlikely(odi->osdname_len >= sizeof(dt_dev->osdname)))
 539                odi->osdname_len = sizeof(dt_dev->osdname) - 1;
 540        dt_dev->osdname[odi->osdname_len] = 0;
 541
 542        /* If it's all zeros something is bad we read past end-of-obj */
 543        return !(odi->systemid_len || odi->osdname_len);
 544}
 545
 546int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs,
 547                      struct exofs_dev **peds)
 548{
 549        struct __alloc_ore_devs_and_exofs_devs {
 550                /* Twice bigger table: See exofs_init_comps() and comment at
 551                 * exofs_read_lookup_dev_table()
 552                 */
 553                struct ore_dev *oreds[numdevs * 2 - 1];
 554                struct exofs_dev eds[numdevs];
 555        } *aoded;
 556        struct exofs_dev *eds;
 557        unsigned i;
 558
 559        aoded = kzalloc(sizeof(*aoded), GFP_KERNEL);
 560        if (unlikely(!aoded)) {
 561                EXOFS_ERR("ERROR: failed allocating Device array[%d]\n",
 562                          numdevs);
 563                return -ENOMEM;
 564        }
 565
 566        sbi->oc.ods = aoded->oreds;
 567        *peds = eds = aoded->eds;
 568        for (i = 0; i < numdevs; ++i)
 569                aoded->oreds[i] = &eds[i].ored;
 570        return 0;
 571}
 572
 573static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi,
 574                                       struct osd_dev *fscb_od,
 575                                       unsigned table_count)
 576{
 577        struct ore_comp comp;
 578        struct exofs_device_table *dt;
 579        struct exofs_dev *eds;
 580        unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) +
 581                                             sizeof(*dt);
 582        unsigned numdevs, i;
 583        int ret;
 584
 585        dt = kmalloc(table_bytes, GFP_KERNEL);
 586        if (unlikely(!dt)) {
 587                EXOFS_ERR("ERROR: allocating %x bytes for device table\n",
 588                          table_bytes);
 589                return -ENOMEM;
 590        }
 591
 592        sbi->oc.numdevs = 0;
 593
 594        comp.obj.partition = sbi->one_comp.obj.partition;
 595        comp.obj.id = EXOFS_DEVTABLE_ID;
 596        exofs_make_credential(comp.cred, &comp.obj);
 597
 598        ret = exofs_read_kern(fscb_od, comp.cred, &comp.obj, 0, dt,
 599                              table_bytes);
 600        if (unlikely(ret)) {
 601                EXOFS_ERR("ERROR: reading device table\n");
 602                goto out;
 603        }
 604
 605        numdevs = le64_to_cpu(dt->dt_num_devices);
 606        if (unlikely(!numdevs)) {
 607                ret = -EINVAL;
 608                goto out;
 609        }
 610        WARN_ON(table_count != numdevs);
 611
 612        ret = _read_and_match_data_map(sbi, numdevs, dt);
 613        if (unlikely(ret))
 614                goto out;
 615
 616        ret = __alloc_dev_table(sbi, numdevs, &eds);
 617        if (unlikely(ret))
 618                goto out;
 619        /* exofs round-robins the device table view according to inode
 620         * number. We hold a: twice bigger table hence inodes can point
 621         * to any device and have a sequential view of the table
 622         * starting at this device. See exofs_init_comps()
 623         */
 624        memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0],
 625                (numdevs - 1) * sizeof(sbi->oc.ods[0]));
 626
 627        /* create sysfs subdir under which we put the device table
 628         * And cluster layout. A Superblock is identified by the string:
 629         *      "dev[0].osdname"_"pid"
 630         */
 631        exofs_sysfs_sb_add(sbi, &dt->dt_dev_table[0]);
 632
 633        for (i = 0; i < numdevs; i++) {
 634                struct exofs_fscb fscb;
 635                struct osd_dev_info odi;
 636                struct osd_dev *od;
 637
 638                if (exofs_devs_2_odi(&dt->dt_dev_table[i], &odi)) {
 639                        EXOFS_ERR("ERROR: Read all-zeros device entry\n");
 640                        ret = -EINVAL;
 641                        goto out;
 642                }
 643
 644                printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n",
 645                       i, odi.osdname);
 646
 647                /* the exofs id is currently the table index */
 648                eds[i].did = i;
 649
 650                /* On all devices the device table is identical. The user can
 651                 * specify any one of the participating devices on the command
 652                 * line. We always keep them in device-table order.
 653                 */
 654                if (fscb_od && osduld_device_same(fscb_od, &odi)) {
 655                        eds[i].ored.od = fscb_od;
 656                        ++sbi->oc.numdevs;
 657                        fscb_od = NULL;
 658                        exofs_sysfs_odev_add(&eds[i], sbi);
 659                        continue;
 660                }
 661
 662                od = osduld_info_lookup(&odi);
 663                if (IS_ERR(od)) {
 664                        ret = PTR_ERR(od);
 665                        EXOFS_ERR("ERROR: device requested is not found "
 666                                  "osd_name-%s =>%d\n", odi.osdname, ret);
 667                        goto out;
 668                }
 669
 670                eds[i].ored.od = od;
 671                ++sbi->oc.numdevs;
 672
 673                /* Read the fscb of the other devices to make sure the FS
 674                 * partition is there.
 675                 */
 676                ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb,
 677                                      sizeof(fscb));
 678                if (unlikely(ret)) {
 679                        EXOFS_ERR("ERROR: Malformed participating device "
 680                                  "error reading fscb osd_name-%s\n",
 681                                  odi.osdname);
 682                        goto out;
 683                }
 684                exofs_sysfs_odev_add(&eds[i], sbi);
 685
 686                /* TODO: verify other information is correct and FS-uuid
 687                 *       matches. Benny what did you say about device table
 688                 *       generation and old devices?
 689                 */
 690        }
 691
 692out:
 693        kfree(dt);
 694        if (unlikely(fscb_od && !ret)) {
 695                        EXOFS_ERR("ERROR: Bad device-table container device not present\n");
 696                        osduld_put_device(fscb_od);
 697                        return -EINVAL;
 698        }
 699        return ret;
 700}
 701
 702/*
 703 * Read the superblock from the OSD and fill in the fields
 704 */
 705static int exofs_fill_super(struct super_block *sb, void *data, int silent)
 706{
 707        struct inode *root;
 708        struct exofs_mountopt *opts = data;
 709        struct exofs_sb_info *sbi;      /*extended info                  */
 710        struct osd_dev *od;             /* Master device                 */
 711        struct exofs_fscb fscb;         /*on-disk superblock info        */
 712        struct ore_comp comp;
 713        unsigned table_count;
 714        int ret;
 715
 716        sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 717        if (!sbi)
 718                return -ENOMEM;
 719
 720        /* use mount options to fill superblock */
 721        if (opts->is_osdname) {
 722                struct osd_dev_info odi = {.systemid_len = 0};
 723
 724                odi.osdname_len = strlen(opts->dev_name);
 725                odi.osdname = (u8 *)opts->dev_name;
 726                od = osduld_info_lookup(&odi);
 727                kfree(opts->dev_name);
 728                opts->dev_name = NULL;
 729        } else {
 730                od = osduld_path_lookup(opts->dev_name);
 731        }
 732        if (IS_ERR(od)) {
 733                ret = -EINVAL;
 734                goto free_sbi;
 735        }
 736
 737        /* Default layout in case we do not have a device-table */
 738        sbi->layout.stripe_unit = PAGE_SIZE;
 739        sbi->layout.mirrors_p1 = 1;
 740        sbi->layout.group_width = 1;
 741        sbi->layout.group_depth = -1;
 742        sbi->layout.group_count = 1;
 743        sbi->s_timeout = opts->timeout;
 744
 745        sbi->one_comp.obj.partition = opts->pid;
 746        sbi->one_comp.obj.id = 0;
 747        exofs_make_credential(sbi->one_comp.cred, &sbi->one_comp.obj);
 748        sbi->oc.single_comp = EC_SINGLE_COMP;
 749        sbi->oc.comps = &sbi->one_comp;
 750
 751        /* fill in some other data by hand */
 752        memset(sb->s_id, 0, sizeof(sb->s_id));
 753        strcpy(sb->s_id, "exofs");
 754        sb->s_blocksize = EXOFS_BLKSIZE;
 755        sb->s_blocksize_bits = EXOFS_BLKSHIFT;
 756        sb->s_maxbytes = MAX_LFS_FILESIZE;
 757        sb->s_max_links = EXOFS_LINK_MAX;
 758        atomic_set(&sbi->s_curr_pending, 0);
 759        sb->s_bdev = NULL;
 760        sb->s_dev = 0;
 761
 762        comp.obj.partition = sbi->one_comp.obj.partition;
 763        comp.obj.id = EXOFS_SUPER_ID;
 764        exofs_make_credential(comp.cred, &comp.obj);
 765
 766        ret = exofs_read_kern(od, comp.cred, &comp.obj, 0, &fscb, sizeof(fscb));
 767        if (unlikely(ret))
 768                goto free_sbi;
 769
 770        sb->s_magic = le16_to_cpu(fscb.s_magic);
 771        /* NOTE: we read below to be backward compatible with old versions */
 772        sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
 773        sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
 774
 775        /* make sure what we read from the object store is correct */
 776        if (sb->s_magic != EXOFS_SUPER_MAGIC) {
 777                if (!silent)
 778                        EXOFS_ERR("ERROR: Bad magic value\n");
 779                ret = -EINVAL;
 780                goto free_sbi;
 781        }
 782        if (le32_to_cpu(fscb.s_version) > EXOFS_FSCB_VER) {
 783                EXOFS_ERR("ERROR: Bad FSCB version expected-%d got-%d\n",
 784                          EXOFS_FSCB_VER, le32_to_cpu(fscb.s_version));
 785                ret = -EINVAL;
 786                goto free_sbi;
 787        }
 788
 789        /* start generation numbers from a random point */
 790        get_random_bytes(&sbi->s_next_generation, sizeof(u32));
 791        spin_lock_init(&sbi->s_next_gen_lock);
 792
 793        table_count = le64_to_cpu(fscb.s_dev_table_count);
 794        if (table_count) {
 795                ret = exofs_read_lookup_dev_table(sbi, od, table_count);
 796                if (unlikely(ret))
 797                        goto free_sbi;
 798        } else {
 799                struct exofs_dev *eds;
 800
 801                ret = __alloc_dev_table(sbi, 1, &eds);
 802                if (unlikely(ret))
 803                        goto free_sbi;
 804
 805                ore_comp_set_dev(&sbi->oc, 0, od);
 806                sbi->oc.numdevs = 1;
 807        }
 808
 809        __sbi_read_stats(sbi);
 810
 811        /* set up operation vectors */
 812        sbi->bdi.ra_pages = __ra_pages(&sbi->layout);
 813        sb->s_bdi = &sbi->bdi;
 814        sb->s_fs_info = sbi;
 815        sb->s_op = &exofs_sops;
 816        sb->s_export_op = &exofs_export_ops;
 817        root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
 818        if (IS_ERR(root)) {
 819                EXOFS_ERR("ERROR: exofs_iget failed\n");
 820                ret = PTR_ERR(root);
 821                goto free_sbi;
 822        }
 823        sb->s_root = d_make_root(root);
 824        if (!sb->s_root) {
 825                EXOFS_ERR("ERROR: get root inode failed\n");
 826                ret = -ENOMEM;
 827                goto free_sbi;
 828        }
 829
 830        if (!S_ISDIR(root->i_mode)) {
 831                dput(sb->s_root);
 832                sb->s_root = NULL;
 833                EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
 834                       root->i_mode);
 835                ret = -EINVAL;
 836                goto free_sbi;
 837        }
 838
 839        ret = bdi_setup_and_register(&sbi->bdi, "exofs", BDI_CAP_MAP_COPY);
 840        if (ret) {
 841                EXOFS_DBGMSG("Failed to bdi_setup_and_register\n");
 842                dput(sb->s_root);
 843                sb->s_root = NULL;
 844                goto free_sbi;
 845        }
 846
 847        exofs_sysfs_dbg_print();
 848        _exofs_print_device("Mounting", opts->dev_name,
 849                            ore_comp_dev(&sbi->oc, 0),
 850                            sbi->one_comp.obj.partition);
 851        return 0;
 852
 853free_sbi:
 854        EXOFS_ERR("Unable to mount exofs on %s pid=0x%llx err=%d\n",
 855                  opts->dev_name, sbi->one_comp.obj.partition, ret);
 856        exofs_free_sbi(sbi);
 857        return ret;
 858}
 859
 860/*
 861 * Set up the superblock (calls exofs_fill_super eventually)
 862 */
 863static struct dentry *exofs_mount(struct file_system_type *type,
 864                          int flags, const char *dev_name,
 865                          void *data)
 866{
 867        struct exofs_mountopt opts;
 868        int ret;
 869
 870        ret = parse_options(data, &opts);
 871        if (ret)
 872                return ERR_PTR(ret);
 873
 874        if (!opts.dev_name)
 875                opts.dev_name = dev_name;
 876        return mount_nodev(type, flags, &opts, exofs_fill_super);
 877}
 878
 879/*
 880 * Return information about the file system state in the buffer.  This is used
 881 * by the 'df' command, for example.
 882 */
 883static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
 884{
 885        struct super_block *sb = dentry->d_sb;
 886        struct exofs_sb_info *sbi = sb->s_fs_info;
 887        struct ore_io_state *ios;
 888        struct osd_attr attrs[] = {
 889                ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
 890                        OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
 891                ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
 892                        OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
 893        };
 894        uint64_t capacity = ULLONG_MAX;
 895        uint64_t used = ULLONG_MAX;
 896        int ret;
 897
 898        ret = ore_get_io_state(&sbi->layout, &sbi->oc, &ios);
 899        if (ret) {
 900                EXOFS_DBGMSG("ore_get_io_state failed.\n");
 901                return ret;
 902        }
 903
 904        ios->in_attr = attrs;
 905        ios->in_attr_len = ARRAY_SIZE(attrs);
 906
 907        ret = ore_read(ios);
 908        if (unlikely(ret))
 909                goto out;
 910
 911        ret = extract_attr_from_ios(ios, &attrs[0]);
 912        if (likely(!ret)) {
 913                capacity = get_unaligned_be64(attrs[0].val_ptr);
 914                if (unlikely(!capacity))
 915                        capacity = ULLONG_MAX;
 916        } else
 917                EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
 918
 919        ret = extract_attr_from_ios(ios, &attrs[1]);
 920        if (likely(!ret))
 921                used = get_unaligned_be64(attrs[1].val_ptr);
 922        else
 923                EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
 924
 925        /* fill in the stats buffer */
 926        buf->f_type = EXOFS_SUPER_MAGIC;
 927        buf->f_bsize = EXOFS_BLKSIZE;
 928        buf->f_blocks = capacity >> 9;
 929        buf->f_bfree = (capacity - used) >> 9;
 930        buf->f_bavail = buf->f_bfree;
 931        buf->f_files = sbi->s_numfiles;
 932        buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
 933        buf->f_namelen = EXOFS_NAME_LEN;
 934
 935out:
 936        ore_put_io_state(ios);
 937        return ret;
 938}
 939
 940static const struct super_operations exofs_sops = {
 941        .alloc_inode    = exofs_alloc_inode,
 942        .destroy_inode  = exofs_destroy_inode,
 943        .write_inode    = exofs_write_inode,
 944        .evict_inode    = exofs_evict_inode,
 945        .put_super      = exofs_put_super,
 946        .sync_fs        = exofs_sync_fs,
 947        .statfs         = exofs_statfs,
 948};
 949
 950/******************************************************************************
 951 * EXPORT OPERATIONS
 952 *****************************************************************************/
 953
 954static struct dentry *exofs_get_parent(struct dentry *child)
 955{
 956        unsigned long ino = exofs_parent_ino(child);
 957
 958        if (!ino)
 959                return ERR_PTR(-ESTALE);
 960
 961        return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
 962}
 963
 964static struct inode *exofs_nfs_get_inode(struct super_block *sb,
 965                u64 ino, u32 generation)
 966{
 967        struct inode *inode;
 968
 969        inode = exofs_iget(sb, ino);
 970        if (IS_ERR(inode))
 971                return ERR_CAST(inode);
 972        if (generation && inode->i_generation != generation) {
 973                /* we didn't find the right inode.. */
 974                iput(inode);
 975                return ERR_PTR(-ESTALE);
 976        }
 977        return inode;
 978}
 979
 980static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
 981                                struct fid *fid, int fh_len, int fh_type)
 982{
 983        return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
 984                                    exofs_nfs_get_inode);
 985}
 986
 987static struct dentry *exofs_fh_to_parent(struct super_block *sb,
 988                                struct fid *fid, int fh_len, int fh_type)
 989{
 990        return generic_fh_to_parent(sb, fid, fh_len, fh_type,
 991                                    exofs_nfs_get_inode);
 992}
 993
 994static const struct export_operations exofs_export_ops = {
 995        .fh_to_dentry = exofs_fh_to_dentry,
 996        .fh_to_parent = exofs_fh_to_parent,
 997        .get_parent = exofs_get_parent,
 998};
 999
1000/******************************************************************************
1001 * INSMOD/RMMOD
1002 *****************************************************************************/
1003
1004/*
1005 * struct that describes this file system
1006 */
1007static struct file_system_type exofs_type = {
1008        .owner          = THIS_MODULE,
1009        .name           = "exofs",
1010        .mount          = exofs_mount,
1011        .kill_sb        = generic_shutdown_super,
1012};
1013
1014static int __init init_exofs(void)
1015{
1016        int err;
1017
1018        err = init_inodecache();
1019        if (err)
1020                goto out;
1021
1022        err = register_filesystem(&exofs_type);
1023        if (err)
1024                goto out_d;
1025
1026        /* We don't fail if sysfs creation failed */
1027        exofs_sysfs_init();
1028
1029        return 0;
1030out_d:
1031        destroy_inodecache();
1032out:
1033        return err;
1034}
1035
1036static void __exit exit_exofs(void)
1037{
1038        exofs_sysfs_uninit();
1039        unregister_filesystem(&exofs_type);
1040        destroy_inodecache();
1041}
1042
1043MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
1044MODULE_DESCRIPTION("exofs");
1045MODULE_LICENSE("GPL");
1046
1047module_init(init_exofs)
1048module_exit(exit_exofs)
1049
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