fs/gfs2/ops_fstype.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/sched.h>
  13 #include <linux/slab.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/completion.h>
  16 #include <linux/buffer_head.h>
  17 #include <linux/blkdev.h>
  18 #include <linux/kthread.h>
  19 #include <linux/export.h>
  20 #include <linux/namei.h>
  21 #include <linux/mount.h>
  22 #include <linux/gfs2_ondisk.h>
  23 #include <linux/quotaops.h>
  24 #include <linux/lockdep.h>
  25 #include <linux/module.h>
  26 #include <linux/backing-dev.h>
  27
  28 #include "gfs2.h"
  29 #include "incore.h"
  30 #include "bmap.h"
  31 #include "glock.h"
  32 #include "glops.h"
  33 #include "inode.h"
  34 #include "recovery.h"
  35 #include "rgrp.h"
  36 #include "super.h"
  37 #include "sys.h"
  38 #include "util.h"
  39 #include "log.h"
  40 #include "quota.h"
  41 #include "dir.h"
  42 #include "meta_io.h"
  43 #include "trace_gfs2.h"
  44
  45 #define DO 0
  46 #define UNDO 1
  47
  48 /**
  49  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  50  * @gt: tune
  51  *
  52  */
  53
  54 static void gfs2_tune_init(struct gfs2_tune *gt)
  55 {
  56         spin_lock_init(&gt->gt_spin);
  57
  58         gt->gt_quota_warn_period = 10;
  59         gt->gt_quota_scale_num = 1;
  60         gt->gt_quota_scale_den = 1;
  61         gt->gt_new_files_jdata = 0;
  62         gt->gt_max_readahead = BIT(18);
  63         gt->gt_complain_secs = 10;
  64 }
  65
  66 static struct gfs2_sbd *init_sbd(struct super_block *sb)
  67 {
  68         struct gfs2_sbd *sdp;
  69         struct address_space *mapping;
  70
  71         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
  72         if (!sdp)
  73                 return NULL;
  74
  75         sb->s_fs_info = sdp;
  76         sdp->sd_vfs = sb;
  77         sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
  78         if (!sdp->sd_lkstats) {
  79                 kfree(sdp);
  80                 return NULL;
  81         }
  82
  83         set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
  84         gfs2_tune_init(&sdp->sd_tune);
  85
  86         init_waitqueue_head(&sdp->sd_glock_wait);
  87         atomic_set(&sdp->sd_glock_disposal, 0);
  88         init_completion(&sdp->sd_locking_init);
  89         init_completion(&sdp->sd_wdack);
  90         spin_lock_init(&sdp->sd_statfs_spin);
  91
  92         spin_lock_init(&sdp->sd_rindex_spin);
  93         sdp->sd_rindex_tree.rb_node = NULL;
  94
  95         INIT_LIST_HEAD(&sdp->sd_jindex_list);
  96         spin_lock_init(&sdp->sd_jindex_spin);
  97         mutex_init(&sdp->sd_jindex_mutex);
  98         init_completion(&sdp->sd_journal_ready);
  99
 100         INIT_LIST_HEAD(&sdp->sd_quota_list);
 101         mutex_init(&sdp->sd_quota_mutex);
 102         mutex_init(&sdp->sd_quota_sync_mutex);
 103         init_waitqueue_head(&sdp->sd_quota_wait);
 104         INIT_LIST_HEAD(&sdp->sd_trunc_list);
 105         spin_lock_init(&sdp->sd_trunc_lock);
 106         spin_lock_init(&sdp->sd_bitmap_lock);
 107
 108         mapping = &sdp->sd_aspace;
 109
 110         address_space_init_once(mapping);
 111         mapping->a_ops = &gfs2_rgrp_aops;
 112         mapping->host = sb->s_bdev->bd_inode;
 113         mapping->flags = 0;
 114         mapping_set_gfp_mask(mapping, GFP_NOFS);
 115         mapping->private_data = NULL;
 116         mapping->writeback_index = 0;
 117
 118         spin_lock_init(&sdp->sd_log_lock);
 119         atomic_set(&sdp->sd_log_pinned, 0);
 120         INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
 121         INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
 122         spin_lock_init(&sdp->sd_ordered_lock);
 123
 124         init_waitqueue_head(&sdp->sd_log_waitq);
 125         init_waitqueue_head(&sdp->sd_logd_waitq);
 126         spin_lock_init(&sdp->sd_ail_lock);
 127         INIT_LIST_HEAD(&sdp->sd_ail1_list);
 128         INIT_LIST_HEAD(&sdp->sd_ail2_list);
 129
 130         init_rwsem(&sdp->sd_log_flush_lock);
 131         atomic_set(&sdp->sd_log_in_flight, 0);
 132         atomic_set(&sdp->sd_reserving_log, 0);
 133         init_waitqueue_head(&sdp->sd_reserving_log_wait);
 134         init_waitqueue_head(&sdp->sd_log_flush_wait);
 135         atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 136         mutex_init(&sdp->sd_freeze_mutex);
 137
 138         return sdp;
 139 }
 140
 141
 142 /**
 143  * gfs2_check_sb - Check superblock
 144  * @sdp: the filesystem
 145  * @sb: The superblock
 146  * @silent: Don't print a message if the check fails
 147  *
 148  * Checks the version code of the FS is one that we understand how to
 149  * read and that the sizes of the various on-disk structures have not
 150  * changed.
 151  */
 152
 153 static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
 154 {
 155         struct gfs2_sb_host *sb = &sdp->sd_sb;
 156
 157         if (sb->sb_magic != GFS2_MAGIC ||
 158             sb->sb_type != GFS2_METATYPE_SB) {
 159                 if (!silent)
 160                         pr_warn("not a GFS2 filesystem\n");
 161                 return -EINVAL;
 162         }
 163
 164         /*  If format numbers match exactly, we're done.  */
 165
 166         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 167             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 168                 return 0;
 169
 170         fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
 171
 172         return -EINVAL;
 173 }
 174
 175 static void end_bio_io_page(struct bio *bio)
 176 {
 177         struct page *page = bio->bi_private;
 178
 179         if (!bio->bi_error)
 180                 SetPageUptodate(page);
 181         else
 182                 pr_warn("error %d reading superblock\n", bio->bi_error);
 183         unlock_page(page);
 184 }
 185
 186 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
 187 {
 188         struct gfs2_sb_host *sb = &sdp->sd_sb;
 189         struct super_block *s = sdp->sd_vfs;
 190         const struct gfs2_sb *str = buf;
 191
 192         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 193         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 194         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 195         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 196         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 197         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 198         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 199         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 200         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 201         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 202         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 203
 204         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 205         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 206         memcpy(s->s_uuid, str->sb_uuid, 16);
 207 }
 208
 209 /**
 210  * gfs2_read_super - Read the gfs2 super block from disk
 211  * @sdp: The GFS2 super block
 212  * @sector: The location of the super block
 213  * @error: The error code to return
 214  *
 215  * This uses the bio functions to read the super block from disk
 216  * because we want to be 100% sure that we never read cached data.
 217  * A super block is read twice only during each GFS2 mount and is
 218  * never written to by the filesystem. The first time its read no
 219  * locks are held, and the only details which are looked at are those
 220  * relating to the locking protocol. Once locking is up and working,
 221  * the sb is read again under the lock to establish the location of
 222  * the master directory (contains pointers to journals etc) and the
 223  * root directory.
 224  *
 225  * Returns: 0 on success or error
 226  */
 227
 228 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
 229 {
 230         struct super_block *sb = sdp->sd_vfs;
 231         struct gfs2_sb *p;
 232         struct page *page;
 233         struct bio *bio;
 234
 235         page = alloc_page(GFP_NOFS);
 236         if (unlikely(!page))
 237                 return -ENOMEM;
 238
 239         ClearPageUptodate(page);
 240         ClearPageDirty(page);
 241         lock_page(page);
 242
 243         bio = bio_alloc(GFP_NOFS, 1);
 244         bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
 245         bio->bi_bdev = sb->s_bdev;
 246         bio_add_page(bio, page, PAGE_SIZE, 0);
 247
 248         bio->bi_end_io = end_bio_io_page;
 249         bio->bi_private = page;
 250         bio_set_op_attrs(bio, REQ_OP_READ, REQ_META);
 251         submit_bio(bio);
 252         wait_on_page_locked(page);
 253         bio_put(bio);
 254         if (!PageUptodate(page)) {
 255                 __free_page(page);
 256                 return -EIO;
 257         }
 258         p = kmap(page);
 259         gfs2_sb_in(sdp, p);
 260         kunmap(page);
 261         __free_page(page);
 262         return gfs2_check_sb(sdp, silent);
 263 }
 264
 265 /**
 266  * gfs2_read_sb - Read super block
 267  * @sdp: The GFS2 superblock
 268  * @silent: Don't print message if mount fails
 269  *
 270  */
 271
 272 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
 273 {
 274         u32 hash_blocks, ind_blocks, leaf_blocks;
 275         u32 tmp_blocks;
 276         unsigned int x;
 277         int error;
 278
 279         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 280         if (error) {
 281                 if (!silent)
 282                         fs_err(sdp, "can't read superblock\n");
 283                 return error;
 284         }
 285
 286         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 287                                GFS2_BASIC_BLOCK_SHIFT;
 288         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
 289         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 290                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 291         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 292                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 293         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 294         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 295         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 296         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 297         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 298                                 sizeof(struct gfs2_meta_header)) /
 299                                 sizeof(struct gfs2_quota_change);
 300         sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
 301                                      sizeof(struct gfs2_meta_header))
 302                 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
 303
 304         /* Compute maximum reservation required to add a entry to a directory */
 305
 306         hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
 307                              sdp->sd_jbsize);
 308
 309         ind_blocks = 0;
 310         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 311                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 312                 ind_blocks += tmp_blocks;
 313         }
 314
 315         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 316
 317         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 318
 319         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 320                                 sizeof(struct gfs2_dinode);
 321         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 322         for (x = 2;; x++) {
 323                 u64 space, d;
 324                 u32 m;
 325
 326                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 327                 d = space;
 328                 m = do_div(d, sdp->sd_inptrs);
 329
 330                 if (d != sdp->sd_heightsize[x - 1] || m)
 331                         break;
 332                 sdp->sd_heightsize[x] = space;
 333         }
 334         sdp->sd_max_height = x;
 335         sdp->sd_heightsize[x] = ~0;
 336         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 337
 338         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 339                                  sizeof(struct gfs2_dinode);
 340         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 341         for (x = 2;; x++) {
 342                 u64 space, d;
 343                 u32 m;
 344
 345                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 346                 d = space;
 347                 m = do_div(d, sdp->sd_inptrs);
 348
 349                 if (d != sdp->sd_jheightsize[x - 1] || m)
 350                         break;
 351                 sdp->sd_jheightsize[x] = space;
 352         }
 353         sdp->sd_max_jheight = x;
 354         sdp->sd_jheightsize[x] = ~0;
 355         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 356
 357         sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
 358                                       sizeof(struct gfs2_leaf)) /
 359                                      GFS2_MIN_DIRENT_SIZE;
 360         return 0;
 361 }
 362
 363 static int init_names(struct gfs2_sbd *sdp, int silent)
 364 {
 365         char *proto, *table;
 366         int error = 0;
 367
 368         proto = sdp->sd_args.ar_lockproto;
 369         table = sdp->sd_args.ar_locktable;
 370
 371         /*  Try to autodetect  */
 372
 373         if (!proto[0] || !table[0]) {
 374                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 375                 if (error)
 376                         return error;
 377
 378                 if (!proto[0])
 379                         proto = sdp->sd_sb.sb_lockproto;
 380                 if (!table[0])
 381                         table = sdp->sd_sb.sb_locktable;
 382         }
 383
 384         if (!table[0])
 385                 table = sdp->sd_vfs->s_id;
 386
 387         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
 388         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
 389
 390         table = sdp->sd_table_name;
 391         while ((table = strchr(table, '/')))
 392                 *table = '_';
 393
 394         return error;
 395 }
 396
 397 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
 398                         int undo)
 399 {
 400         int error = 0;
 401
 402         if (undo)
 403                 goto fail_trans;
 404
 405         error = gfs2_glock_nq_num(sdp,
 406                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
 407                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
 408                                   mount_gh);
 409         if (error) {
 410                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
 411                 goto fail;
 412         }
 413
 414         error = gfs2_glock_nq_num(sdp,
 415                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
 416                                   LM_ST_SHARED,
 417                                   LM_FLAG_NOEXP | GL_EXACT,
 418                                   &sdp->sd_live_gh);
 419         if (error) {
 420                 fs_err(sdp, "can't acquire live glock: %d\n", error);
 421                 goto fail_mount;
 422         }
 423
 424         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
 425                                CREATE, &sdp->sd_rename_gl);
 426         if (error) {
 427                 fs_err(sdp, "can't create rename glock: %d\n", error);
 428                 goto fail_live;
 429         }
 430
 431         error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
 432                                CREATE, &sdp->sd_freeze_gl);
 433         if (error) {
 434                 fs_err(sdp, "can't create transaction glock: %d\n", error);
 435                 goto fail_rename;
 436         }
 437
 438         return 0;
 439
 440 fail_trans:
 441         gfs2_glock_put(sdp->sd_freeze_gl);
 442 fail_rename:
 443         gfs2_glock_put(sdp->sd_rename_gl);
 444 fail_live:
 445         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 446 fail_mount:
 447         gfs2_glock_dq_uninit(mount_gh);
 448 fail:
 449         return error;
 450 }
 451
 452 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
 453                             u64 no_addr, const char *name)
 454 {
 455         struct gfs2_sbd *sdp = sb->s_fs_info;
 456         struct dentry *dentry;
 457         struct inode *inode;
 458
 459         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
 460                                   GFS2_BLKST_FREE /* ignore */);
 461         if (IS_ERR(inode)) {
 462                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
 463                 return PTR_ERR(inode);
 464         }
 465         dentry = d_make_root(inode);
 466         if (!dentry) {
 467                 fs_err(sdp, "can't alloc %s dentry\n", name);
 468                 return -ENOMEM;
 469         }
 470         *dptr = dentry;
 471         return 0;
 472 }
 473
 474 static int init_sb(struct gfs2_sbd *sdp, int silent)
 475 {
 476         struct super_block *sb = sdp->sd_vfs;
 477         struct gfs2_holder sb_gh;
 478         u64 no_addr;
 479         int ret;
 480
 481         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
 482                                 LM_ST_SHARED, 0, &sb_gh);
 483         if (ret) {
 484                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
 485                 return ret;
 486         }
 487
 488         ret = gfs2_read_sb(sdp, silent);
 489         if (ret) {
 490                 fs_err(sdp, "can't read superblock: %d\n", ret);
 491                 goto out;
 492         }
 493
 494         /* Set up the buffer cache and SB for real */
 495         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
 496                 ret = -EINVAL;
 497                 fs_err(sdp, "FS block size (%u) is too small for device "
 498                        "block size (%u)\n",
 499                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
 500                 goto out;
 501         }
 502         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
 503                 ret = -EINVAL;
 504                 fs_err(sdp, "FS block size (%u) is too big for machine "
 505                        "page size (%u)\n",
 506                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
 507                 goto out;
 508         }
 509         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
 510
 511         /* Get the root inode */
 512         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
 513         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
 514         if (ret)
 515                 goto out;
 516
 517         /* Get the master inode */
 518         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
 519         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
 520         if (ret) {
 521                 dput(sdp->sd_root_dir);
 522                 goto out;
 523         }
 524         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
 525 out:
 526         gfs2_glock_dq_uninit(&sb_gh);
 527         return ret;
 528 }
 529
 530 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
 531 {
 532         char *message = "FIRSTMOUNT=Done";
 533         char *envp[] = { message, NULL };
 534
 535         fs_info(sdp, "first mount done, others may mount\n");
 536
 537         if (sdp->sd_lockstruct.ls_ops->lm_first_done)
 538                 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
 539
 540         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 541 }
 542
 543 /**
 544  * gfs2_jindex_hold - Grab a lock on the jindex
 545  * @sdp: The GFS2 superblock
 546  * @ji_gh: the holder for the jindex glock
 547  *
 548  * Returns: errno
 549  */
 550
 551 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 552 {
 553         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 554         struct qstr name;
 555         char buf[20];
 556         struct gfs2_jdesc *jd;
 557         int error;
 558
 559         name.name = buf;
 560
 561         mutex_lock(&sdp->sd_jindex_mutex);
 562
 563         for (;;) {
 564                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 565                 if (error)
 566                         break;
 567
 568                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 569                 name.hash = gfs2_disk_hash(name.name, name.len);
 570
 571                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 572                 if (error == -ENOENT) {
 573                         error = 0;
 574                         break;
 575                 }
 576
 577                 gfs2_glock_dq_uninit(ji_gh);
 578
 579                 if (error)
 580                         break;
 581
 582                 error = -ENOMEM;
 583                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 584                 if (!jd)
 585                         break;
 586
 587                 INIT_LIST_HEAD(&jd->extent_list);
 588                 INIT_LIST_HEAD(&jd->jd_revoke_list);
 589
 590                 INIT_WORK(&jd->jd_work, gfs2_recover_func);
 591                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
 592                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 593                         if (!jd->jd_inode)
 594                                 error = -ENOENT;
 595                         else
 596                                 error = PTR_ERR(jd->jd_inode);
 597                         kfree(jd);
 598                         break;
 599                 }
 600
 601                 spin_lock(&sdp->sd_jindex_spin);
 602                 jd->jd_jid = sdp->sd_journals++;
 603                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 604                 spin_unlock(&sdp->sd_jindex_spin);
 605         }
 606
 607         mutex_unlock(&sdp->sd_jindex_mutex);
 608
 609         return error;
 610 }
 611
 612 /**
 613  * check_journal_clean - Make sure a journal is clean for a spectator mount
 614  * @sdp: The GFS2 superblock
 615  * @jd: The journal descriptor
 616  *
 617  * Returns: 0 if the journal is clean or locked, else an error
 618  */
 619 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
 620 {
 621         int error;
 622         struct gfs2_holder j_gh;
 623         struct gfs2_log_header_host head;
 624         struct gfs2_inode *ip;
 625
 626         ip = GFS2_I(jd->jd_inode);
 627         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
 628                                    GL_EXACT | GL_NOCACHE, &j_gh);
 629         if (error) {
 630                 fs_err(sdp, "Error locking journal for spectator mount.\n");
 631                 return -EPERM;
 632         }
 633         error = gfs2_jdesc_check(jd);
 634         if (error) {
 635                 fs_err(sdp, "Error checking journal for spectator mount.\n");
 636                 goto out_unlock;
 637         }
 638         error = gfs2_find_jhead(jd, &head);
 639         if (error) {
 640                 fs_err(sdp, "Error parsing journal for spectator mount.\n");
 641                 goto out_unlock;
 642         }
 643         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 644                 error = -EPERM;
 645                 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
 646                        "must not be a spectator.\n", jd->jd_jid);
 647         }
 648
 649 out_unlock:
 650         gfs2_glock_dq_uninit(&j_gh);
 651         return error;
 652 }
 653
 654 static int init_journal(struct gfs2_sbd *sdp, int undo)
 655 {
 656         struct inode *master = d_inode(sdp->sd_master_dir);
 657         struct gfs2_holder ji_gh;
 658         struct gfs2_inode *ip;
 659         int jindex = 1;
 660         int error = 0;
 661
 662         if (undo) {
 663                 jindex = 0;
 664                 goto fail_jinode_gh;
 665         }
 666
 667         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
 668         if (IS_ERR(sdp->sd_jindex)) {
 669                 fs_err(sdp, "can't lookup journal index: %d\n", error);
 670                 return PTR_ERR(sdp->sd_jindex);
 671         }
 672
 673         /* Load in the journal index special file */
 674
 675         error = gfs2_jindex_hold(sdp, &ji_gh);
 676         if (error) {
 677                 fs_err(sdp, "can't read journal index: %d\n", error);
 678                 goto fail;
 679         }
 680
 681         error = -EUSERS;
 682         if (!gfs2_jindex_size(sdp)) {
 683                 fs_err(sdp, "no journals!\n");
 684                 goto fail_jindex;
 685         }
 686
 687         atomic_set(&sdp->sd_log_blks_needed, 0);
 688         if (sdp->sd_args.ar_spectator) {
 689                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
 690                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 691                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 692                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 693         } else {
 694                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
 695                         fs_err(sdp, "can't mount journal #%u\n",
 696                                sdp->sd_lockstruct.ls_jid);
 697                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
 698                                gfs2_jindex_size(sdp),
 699                                gfs2_jindex_size(sdp) - 1);
 700                         goto fail_jindex;
 701                 }
 702                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
 703
 704                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
 705                                           &gfs2_journal_glops,
 706                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
 707                                           &sdp->sd_journal_gh);
 708                 if (error) {
 709                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
 710                         goto fail_jindex;
 711                 }
 712
 713                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 714                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 715                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
 716                                            &sdp->sd_jinode_gh);
 717                 if (error) {
 718                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
 719                                error);
 720                         goto fail_journal_gh;
 721                 }
 722
 723                 error = gfs2_jdesc_check(sdp->sd_jdesc);
 724                 if (error) {
 725                         fs_err(sdp, "my journal (%u) is bad: %d\n",
 726                                sdp->sd_jdesc->jd_jid, error);
 727                         goto fail_jinode_gh;
 728                 }
 729                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 730                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 731                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 732
 733                 /* Map the extents for this journal's blocks */
 734                 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
 735         }
 736         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
 737
 738         if (sdp->sd_lockstruct.ls_first) {
 739                 unsigned int x;
 740                 for (x = 0; x < sdp->sd_journals; x++) {
 741                         struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
 742
 743                         if (sdp->sd_args.ar_spectator) {
 744                                 error = check_journal_clean(sdp, jd);
 745                                 if (error)
 746                                         goto fail_jinode_gh;
 747                                 continue;
 748                         }
 749                         error = gfs2_recover_journal(jd, true);
 750                         if (error) {
 751                                 fs_err(sdp, "error recovering journal %u: %d\n",
 752                                        x, error);
 753                                 goto fail_jinode_gh;
 754                         }
 755                 }
 756
 757                 gfs2_others_may_mount(sdp);
 758         } else if (!sdp->sd_args.ar_spectator) {
 759                 error = gfs2_recover_journal(sdp->sd_jdesc, true);
 760                 if (error) {
 761                         fs_err(sdp, "error recovering my journal: %d\n", error);
 762                         goto fail_jinode_gh;
 763                 }
 764         }
 765
 766         sdp->sd_log_idle = 1;
 767         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
 768         gfs2_glock_dq_uninit(&ji_gh);
 769         jindex = 0;
 770         INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
 771         return 0;
 772
 773 fail_jinode_gh:
 774         if (!sdp->sd_args.ar_spectator)
 775                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 776 fail_journal_gh:
 777         if (!sdp->sd_args.ar_spectator)
 778                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 779 fail_jindex:
 780         gfs2_jindex_free(sdp);
 781         if (jindex)
 782                 gfs2_glock_dq_uninit(&ji_gh);
 783 fail:
 784         iput(sdp->sd_jindex);
 785         return error;
 786 }
 787
 788 static struct lock_class_key gfs2_quota_imutex_key;
 789
 790 static int init_inodes(struct gfs2_sbd *sdp, int undo)
 791 {
 792         int error = 0;
 793         struct inode *master = d_inode(sdp->sd_master_dir);
 794
 795         if (undo)
 796                 goto fail_qinode;
 797
 798         error = init_journal(sdp, undo);
 799         complete_all(&sdp->sd_journal_ready);
 800         if (error)
 801                 goto fail;
 802
 803         /* Read in the master statfs inode */
 804         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
 805         if (IS_ERR(sdp->sd_statfs_inode)) {
 806                 error = PTR_ERR(sdp->sd_statfs_inode);
 807                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
 808                 goto fail_journal;
 809         }
 810
 811         /* Read in the resource index inode */
 812         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
 813         if (IS_ERR(sdp->sd_rindex)) {
 814                 error = PTR_ERR(sdp->sd_rindex);
 815                 fs_err(sdp, "can't get resource index inode: %d\n", error);
 816                 goto fail_statfs;
 817         }
 818         sdp->sd_rindex_uptodate = 0;
 819
 820         /* Read in the quota inode */
 821         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
 822         if (IS_ERR(sdp->sd_quota_inode)) {
 823                 error = PTR_ERR(sdp->sd_quota_inode);
 824                 fs_err(sdp, "can't get quota file inode: %d\n", error);
 825                 goto fail_rindex;
 826         }
 827         /*
 828          * i_mutex on quota files is special. Since this inode is hidden system
 829          * file, we are safe to define locking ourselves.
 830          */
 831         lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
 832                           &gfs2_quota_imutex_key);
 833
 834         error = gfs2_rindex_update(sdp);
 835         if (error)
 836                 goto fail_qinode;
 837
 838         return 0;
 839
 840 fail_qinode:
 841         iput(sdp->sd_quota_inode);
 842 fail_rindex:
 843         gfs2_clear_rgrpd(sdp);
 844         iput(sdp->sd_rindex);
 845 fail_statfs:
 846         iput(sdp->sd_statfs_inode);
 847 fail_journal:
 848         init_journal(sdp, UNDO);
 849 fail:
 850         return error;
 851 }
 852
 853 static int init_per_node(struct gfs2_sbd *sdp, int undo)
 854 {
 855         struct inode *pn = NULL;
 856         char buf[30];
 857         int error = 0;
 858         struct gfs2_inode *ip;
 859         struct inode *master = d_inode(sdp->sd_master_dir);
 860
 861         if (sdp->sd_args.ar_spectator)
 862                 return 0;
 863
 864         if (undo)
 865                 goto fail_qc_gh;
 866
 867         pn = gfs2_lookup_simple(master, "per_node");
 868         if (IS_ERR(pn)) {
 869                 error = PTR_ERR(pn);
 870                 fs_err(sdp, "can't find per_node directory: %d\n", error);
 871                 return error;
 872         }
 873
 874         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
 875         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
 876         if (IS_ERR(sdp->sd_sc_inode)) {
 877                 error = PTR_ERR(sdp->sd_sc_inode);
 878                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
 879                 goto fail;
 880         }
 881
 882         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
 883         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
 884         if (IS_ERR(sdp->sd_qc_inode)) {
 885                 error = PTR_ERR(sdp->sd_qc_inode);
 886                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
 887                 goto fail_ut_i;
 888         }
 889
 890         iput(pn);
 891         pn = NULL;
 892
 893         ip = GFS2_I(sdp->sd_sc_inode);
 894         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 895                                    &sdp->sd_sc_gh);
 896         if (error) {
 897                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
 898                 goto fail_qc_i;
 899         }
 900
 901         ip = GFS2_I(sdp->sd_qc_inode);
 902         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 903                                    &sdp->sd_qc_gh);
 904         if (error) {
 905                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
 906                 goto fail_ut_gh;
 907         }
 908
 909         return 0;
 910
 911 fail_qc_gh:
 912         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 913 fail_ut_gh:
 914         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 915 fail_qc_i:
 916         iput(sdp->sd_qc_inode);
 917 fail_ut_i:
 918         iput(sdp->sd_sc_inode);
 919 fail:
 920         iput(pn);
 921         return error;
 922 }
 923
 924 static const match_table_t nolock_tokens = {
 925         { Opt_jid, "jid=%d\n", },
 926         { Opt_err, NULL },
 927 };
 928
 929 static const struct lm_lockops nolock_ops = {
 930         .lm_proto_name = "lock_nolock",
 931         .lm_put_lock = gfs2_glock_free,
 932         .lm_tokens = &nolock_tokens,
 933 };
 934
 935 /**
 936  * gfs2_lm_mount - mount a locking protocol
 937  * @sdp: the filesystem
 938  * @args: mount arguments
 939  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
 940  *
 941  * Returns: errno
 942  */
 943
 944 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 945 {
 946         const struct lm_lockops *lm;
 947         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 948         struct gfs2_args *args = &sdp->sd_args;
 949         const char *proto = sdp->sd_proto_name;
 950         const char *table = sdp->sd_table_name;
 951         char *o, *options;
 952         int ret;
 953
 954         if (!strcmp("lock_nolock", proto)) {
 955                 lm = &nolock_ops;
 956                 sdp->sd_args.ar_localflocks = 1;
 957 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
 958         } else if (!strcmp("lock_dlm", proto)) {
 959                 lm = &gfs2_dlm_ops;
 960 #endif
 961         } else {
 962                 pr_info("can't find protocol %s\n", proto);
 963                 return -ENOENT;
 964         }
 965
 966         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
 967
 968         ls->ls_ops = lm;
 969         ls->ls_first = 1;
 970
 971         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
 972                 substring_t tmp[MAX_OPT_ARGS];
 973                 int token, option;
 974
 975                 if (!o || !*o)
 976                         continue;
 977
 978                 token = match_token(o, *lm->lm_tokens, tmp);
 979                 switch (token) {
 980                 case Opt_jid:
 981                         ret = match_int(&tmp[0], &option);
 982                         if (ret || option < 0)
 983                                 goto hostdata_error;
 984                         if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
 985                                 ls->ls_jid = option;
 986                         break;
 987                 case Opt_id:
 988                 case Opt_nodir:
 989                         /* Obsolete, but left for backward compat purposes */
 990                         break;
 991                 case Opt_first:
 992                         ret = match_int(&tmp[0], &option);
 993                         if (ret || (option != 0 && option != 1))
 994                                 goto hostdata_error;
 995                         ls->ls_first = option;
 996                         break;
 997                 case Opt_err:
 998                 default:
 999 hostdata_error:
1000                         fs_info(sdp, "unknown hostdata (%s)\n", o);
1001                         return -EINVAL;
1002                 }
1003         }
1004
1005         if (lm->lm_mount == NULL) {
1006                 fs_info(sdp, "Now mounting FS...\n");
1007                 complete_all(&sdp->sd_locking_init);
1008                 return 0;
1009         }
1010         ret = lm->lm_mount(sdp, table);
1011         if (ret == 0)
1012                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1013         complete_all(&sdp->sd_locking_init);
1014         return ret;
1015 }
1016
1017 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1018 {
1019         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1020         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1021             lm->lm_unmount)
1022                 lm->lm_unmount(sdp);
1023 }
1024
1025 static int wait_on_journal(struct gfs2_sbd *sdp)
1026 {
1027         if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
1028                 return 0;
1029
1030         return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
1031                 ? -EINTR : 0;
1032 }
1033
1034 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1035 {
1036         struct super_block *sb = sdp->sd_vfs;
1037         char ro[20];
1038         char spectator[20];
1039         char *envp[] = { ro, spectator, NULL };
1040         sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
1041         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1042         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1043 }
1044
1045 /**
1046  * fill_super - Read in superblock
1047  * @sb: The VFS superblock
1048  * @data: Mount options
1049  * @silent: Don't complain if it's not a GFS2 filesystem
1050  *
1051  * Returns: errno
1052  */
1053
1054 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1055 {
1056         struct gfs2_sbd *sdp;
1057         struct gfs2_holder mount_gh;
1058         int error;
1059
1060         sdp = init_sbd(sb);
1061         if (!sdp) {
1062                 pr_warn("can't alloc struct gfs2_sbd\n");
1063                 return -ENOMEM;
1064         }
1065         sdp->sd_args = *args;
1066
1067         if (sdp->sd_args.ar_spectator) {
1068                 sb->s_flags |= MS_RDONLY;
1069                 set_bit(SDF_RORECOVERY, &sdp->sd_flags);
1070         }
1071         if (sdp->sd_args.ar_posix_acl)
1072                 sb->s_flags |= MS_POSIXACL;
1073         if (sdp->sd_args.ar_nobarrier)
1074                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1075
1076         sb->s_flags |= MS_NOSEC;
1077         sb->s_magic = GFS2_MAGIC;
1078         sb->s_op = &gfs2_super_ops;
1079         sb->s_d_op = &gfs2_dops;
1080         sb->s_export_op = &gfs2_export_ops;
1081         sb->s_xattr = gfs2_xattr_handlers;
1082         sb->s_qcop = &gfs2_quotactl_ops;
1083         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1084         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1085         sb->s_time_gran = 1;
1086         sb->s_maxbytes = MAX_LFS_FILESIZE;
1087
1088         /* Set up the buffer cache and fill in some fake block size values
1089            to allow us to read-in the on-disk superblock. */
1090         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1091         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1092         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1093                                GFS2_BASIC_BLOCK_SHIFT;
1094         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
1095
1096         sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
1097         sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1098         if (sdp->sd_args.ar_statfs_quantum) {
1099                 sdp->sd_tune.gt_statfs_slow = 0;
1100                 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1101         } else {
1102                 sdp->sd_tune.gt_statfs_slow = 1;
1103                 sdp->sd_tune.gt_statfs_quantum = 30;
1104         }
1105
1106         error = init_names(sdp, silent);
1107         if (error) {
1108                 /* In this case, we haven't initialized sysfs, so we have to
1109                    manually free the sdp. */
1110                 free_percpu(sdp->sd_lkstats);
1111                 kfree(sdp);
1112                 sb->s_fs_info = NULL;
1113                 return error;
1114         }
1115
1116         snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s", sdp->sd_table_name);
1117
1118         error = gfs2_sys_fs_add(sdp);
1119         /*
1120          * If we hit an error here, gfs2_sys_fs_add will have called function
1121          * kobject_put which causes the sysfs usage count to go to zero, which
1122          * causes sysfs to call function gfs2_sbd_release, which frees sdp.
1123          * Subsequent error paths here will call gfs2_sys_fs_del, which also
1124          * kobject_put to free sdp.
1125          */
1126         if (error)
1127                 return error;
1128
1129         gfs2_create_debugfs_file(sdp);
1130
1131         error = gfs2_lm_mount(sdp, silent);
1132         if (error)
1133                 goto fail_debug;
1134
1135         error = init_locking(sdp, &mount_gh, DO);
1136         if (error)
1137                 goto fail_lm;
1138
1139         error = init_sb(sdp, silent);
1140         if (error)
1141                 goto fail_locking;
1142
1143         error = wait_on_journal(sdp);
1144         if (error)
1145                 goto fail_sb;
1146
1147         /*
1148          * If user space has failed to join the cluster or some similar
1149          * failure has occurred, then the journal id will contain a
1150          * negative (error) number. This will then be returned to the
1151          * caller (of the mount syscall). We do this even for spectator
1152          * mounts (which just write a jid of 0 to indicate "ok" even though
1153          * the jid is unused in the spectator case)
1154          */
1155         if (sdp->sd_lockstruct.ls_jid < 0) {
1156                 error = sdp->sd_lockstruct.ls_jid;
1157                 sdp->sd_lockstruct.ls_jid = 0;
1158                 goto fail_sb;
1159         }
1160
1161         if (sdp->sd_args.ar_spectator)
1162                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.s",
1163                          sdp->sd_table_name);
1164         else
1165                 snprintf(sdp->sd_fsname, GFS2_FSNAME_LEN, "%s.%u",
1166                          sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
1167
1168         error = init_inodes(sdp, DO);
1169         if (error)
1170                 goto fail_sb;
1171
1172         error = init_per_node(sdp, DO);
1173         if (error)
1174                 goto fail_inodes;
1175
1176         error = gfs2_statfs_init(sdp);
1177         if (error) {
1178                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1179                 goto fail_per_node;
1180         }
1181
1182         if (!(sb->s_flags & MS_RDONLY)) {
1183                 error = gfs2_make_fs_rw(sdp);
1184                 if (error) {
1185                         fs_err(sdp, "can't make FS RW: %d\n", error);
1186                         goto fail_per_node;
1187                 }
1188         }
1189
1190         gfs2_glock_dq_uninit(&mount_gh);
1191         gfs2_online_uevent(sdp);
1192         return 0;
1193
1194 fail_per_node:
1195         init_per_node(sdp, UNDO);
1196 fail_inodes:
1197         init_inodes(sdp, UNDO);
1198 fail_sb:
1199         if (sdp->sd_root_dir)
1200                 dput(sdp->sd_root_dir);
1201         if (sdp->sd_master_dir)
1202                 dput(sdp->sd_master_dir);
1203         if (sb->s_root)
1204                 dput(sb->s_root);
1205         sb->s_root = NULL;
1206 fail_locking:
1207         init_locking(sdp, &mount_gh, UNDO);
1208 fail_lm:
1209         complete_all(&sdp->sd_journal_ready);
1210         gfs2_gl_hash_clear(sdp);
1211         gfs2_lm_unmount(sdp);
1212 fail_debug:
1213         gfs2_delete_debugfs_file(sdp);
1214         free_percpu(sdp->sd_lkstats);
1215         /* gfs2_sys_fs_del must be the last thing we do, since it causes
1216          * sysfs to call function gfs2_sbd_release, which frees sdp. */
1217         gfs2_sys_fs_del(sdp);
1218         sb->s_fs_info = NULL;
1219         return error;
1220 }
1221
1222 static int set_gfs2_super(struct super_block *s, void *data)
1223 {
1224         s->s_bdev = data;
1225         s->s_dev = s->s_bdev->bd_dev;
1226         s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
1227         s->s_iflags |= SB_I_DYNBDI;
1228         return 0;
1229 }
1230
1231 static int test_gfs2_super(struct super_block *s, void *ptr)
1232 {
1233         struct block_device *bdev = ptr;
1234         return (bdev == s->s_bdev);
1235 }
1236
1237 /**
1238  * gfs2_mount - Get the GFS2 superblock
1239  * @fs_type: The GFS2 filesystem type
1240  * @flags: Mount flags
1241  * @dev_name: The name of the device
1242  * @data: The mount arguments
1243  *
1244  * Q. Why not use get_sb_bdev() ?
1245  * A. We need to select one of two root directories to mount, independent
1246  *    of whether this is the initial, or subsequent, mount of this sb
1247  *
1248  * Returns: 0 or -ve on error
1249  */
1250
1251 static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
1252                        const char *dev_name, void *data)
1253 {
1254         struct block_device *bdev;
1255         struct super_block *s;
1256         fmode_t mode = FMODE_READ | FMODE_EXCL;
1257         int error;
1258         struct gfs2_args args;
1259         struct gfs2_sbd *sdp;
1260
1261         if (!(flags & MS_RDONLY))
1262                 mode |= FMODE_WRITE;
1263
1264         bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1265         if (IS_ERR(bdev))
1266                 return ERR_CAST(bdev);
1267
1268         /*
1269          * once the super is inserted into the list by sget, s_umount
1270          * will protect the lockfs code from trying to start a snapshot
1271          * while we are mounting
1272          */
1273         mutex_lock(&bdev->bd_fsfreeze_mutex);
1274         if (bdev->bd_fsfreeze_count > 0) {
1275                 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1276                 error = -EBUSY;
1277                 goto error_bdev;
1278         }
1279         s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
1280         mutex_unlock(&bdev->bd_fsfreeze_mutex);
1281         error = PTR_ERR(s);
1282         if (IS_ERR(s))
1283                 goto error_bdev;
1284
1285         if (s->s_root) {
1286                 /*
1287                  * s_umount nests inside bd_mutex during
1288                  * __invalidate_device().  blkdev_put() acquires
1289                  * bd_mutex and can't be called under s_umount.  Drop
1290                  * s_umount temporarily.  This is safe as we're
1291                  * holding an active reference.
1292                  */
1293                 up_write(&s->s_umount);
1294                 blkdev_put(bdev, mode);
1295                 down_write(&s->s_umount);
1296         } else {
1297                 /* s_mode must be set before deactivate_locked_super calls */
1298                 s->s_mode = mode;
1299         }
1300
1301         memset(&args, 0, sizeof(args));
1302         args.ar_quota = GFS2_QUOTA_DEFAULT;
1303         args.ar_data = GFS2_DATA_DEFAULT;
1304         args.ar_commit = 30;
1305         args.ar_statfs_quantum = 30;
1306         args.ar_quota_quantum = 60;
1307         args.ar_errors = GFS2_ERRORS_DEFAULT;
1308
1309         error = gfs2_mount_args(&args, data);
1310         if (error) {
1311                 pr_warn("can't parse mount arguments\n");
1312                 goto error_super;
1313         }
1314
1315         if (s->s_root) {
1316                 error = -EBUSY;
1317                 if ((flags ^ s->s_flags) & MS_RDONLY)
1318                         goto error_super;
1319         } else {
1320                 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1321                 sb_set_blocksize(s, block_size(bdev));
1322                 error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
1323                 if (error)
1324                         goto error_super;
1325                 s->s_flags |= MS_ACTIVE;
1326                 bdev->bd_super = s;
1327         }
1328
1329         sdp = s->s_fs_info;
1330         if (args.ar_meta)
1331                 return dget(sdp->sd_master_dir);
1332         else
1333                 return dget(sdp->sd_root_dir);
1334
1335 error_super:
1336         deactivate_locked_super(s);
1337         return ERR_PTR(error);
1338 error_bdev:
1339         blkdev_put(bdev, mode);
1340         return ERR_PTR(error);
1341 }
1342
1343 static int set_meta_super(struct super_block *s, void *ptr)
1344 {
1345         return -EINVAL;
1346 }
1347
1348 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1349                         int flags, const char *dev_name, void *data)
1350 {
1351         struct super_block *s;
1352         struct gfs2_sbd *sdp;
1353         struct path path;
1354         int error;
1355
1356         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1357         if (error) {
1358                 pr_warn("path_lookup on %s returned error %d\n",
1359                         dev_name, error);
1360                 return ERR_PTR(error);
1361         }
1362         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1363                  path.dentry->d_sb->s_bdev);
1364         path_put(&path);
1365         if (IS_ERR(s)) {
1366                 pr_warn("gfs2 mount does not exist\n");
1367                 return ERR_CAST(s);
1368         }
1369         if ((flags ^ s->s_flags) & MS_RDONLY) {
1370                 deactivate_locked_super(s);
1371                 return ERR_PTR(-EBUSY);
1372         }
1373         sdp = s->s_fs_info;
1374         return dget(sdp->sd_master_dir);
1375 }
1376
1377 static void gfs2_kill_sb(struct super_block *sb)
1378 {
1379         struct gfs2_sbd *sdp = sb->s_fs_info;
1380
1381         if (sdp == NULL) {
1382                 kill_block_super(sb);
1383                 return;
1384         }
1385
1386         gfs2_log_flush(sdp, NULL, SYNC_FLUSH);
1387         dput(sdp->sd_root_dir);
1388         dput(sdp->sd_master_dir);
1389         sdp->sd_root_dir = NULL;
1390         sdp->sd_master_dir = NULL;
1391         shrink_dcache_sb(sb);
1392         gfs2_delete_debugfs_file(sdp);
1393         free_percpu(sdp->sd_lkstats);
1394         kill_block_super(sb);
1395 }
1396
1397 struct file_system_type gfs2_fs_type = {
1398         .name = "gfs2",
1399         .fs_flags = FS_REQUIRES_DEV,
1400         .mount = gfs2_mount,
1401         .kill_sb = gfs2_kill_sb,
1402         .owner = THIS_MODULE,
1403 };
1404 MODULE_ALIAS_FS("gfs2");
1405
1406 struct file_system_type gfs2meta_fs_type = {
1407         .name = "gfs2meta",
1408         .fs_flags = FS_REQUIRES_DEV,
1409         .mount = gfs2_mount_meta,
1410         .owner = THIS_MODULE,
1411 };
1412 MODULE_ALIAS_FS("gfs2meta");