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 #include "lops.h"
  45
  46 #define DO 0
  47 #define UNDO 1
  48
  49 /**
  50  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  51  * @gt: tune
  52  *
  53  */
  54
  55 static void gfs2_tune_init(struct gfs2_tune *gt)
  56 {
  57         spin_lock_init(&gt->gt_spin);
  58
  59         gt->gt_quota_warn_period = 10;
  60         gt->gt_quota_scale_num = 1;
  61         gt->gt_quota_scale_den = 1;
  62         gt->gt_new_files_jdata = 0;
  63         gt->gt_max_readahead = BIT(18);
  64         gt->gt_complain_secs = 10;
  65 }
  66
  67 static struct gfs2_sbd *init_sbd(struct super_block *sb)
  68 {
  69         struct gfs2_sbd *sdp;
  70         struct address_space *mapping;
  71
  72         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
  73         if (!sdp)
  74                 return NULL;
  75
  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         sb->s_fs_info = sdp;
  83
  84         set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
  85         gfs2_tune_init(&sdp->sd_tune);
  86
  87         init_waitqueue_head(&sdp->sd_glock_wait);
  88         atomic_set(&sdp->sd_glock_disposal, 0);
  89         init_completion(&sdp->sd_locking_init);
  90         init_completion(&sdp->sd_wdack);
  91         spin_lock_init(&sdp->sd_statfs_spin);
  92
  93         spin_lock_init(&sdp->sd_rindex_spin);
  94         sdp->sd_rindex_tree.rb_node = NULL;
  95
  96         INIT_LIST_HEAD(&sdp->sd_jindex_list);
  97         spin_lock_init(&sdp->sd_jindex_spin);
  98         mutex_init(&sdp->sd_jindex_mutex);
  99         init_completion(&sdp->sd_journal_ready);
 100
 101         INIT_LIST_HEAD(&sdp->sd_quota_list);
 102         mutex_init(&sdp->sd_quota_mutex);
 103         mutex_init(&sdp->sd_quota_sync_mutex);
 104         init_waitqueue_head(&sdp->sd_quota_wait);
 105         INIT_LIST_HEAD(&sdp->sd_trunc_list);
 106         spin_lock_init(&sdp->sd_trunc_lock);
 107         spin_lock_init(&sdp->sd_bitmap_lock);
 108
 109         mapping = &sdp->sd_aspace;
 110
 111         address_space_init_once(mapping);
 112         mapping->a_ops = &gfs2_rgrp_aops;
 113         mapping->host = sb->s_bdev->bd_inode;
 114         mapping->flags = 0;
 115         mapping_set_gfp_mask(mapping, GFP_NOFS);
 116         mapping->private_data = NULL;
 117         mapping->writeback_index = 0;
 118
 119         spin_lock_init(&sdp->sd_log_lock);
 120         atomic_set(&sdp->sd_log_pinned, 0);
 121         INIT_LIST_HEAD(&sdp->sd_log_le_revoke);
 122         INIT_LIST_HEAD(&sdp->sd_log_le_ordered);
 123         spin_lock_init(&sdp->sd_ordered_lock);
 124
 125         init_waitqueue_head(&sdp->sd_log_waitq);
 126         init_waitqueue_head(&sdp->sd_logd_waitq);
 127         spin_lock_init(&sdp->sd_ail_lock);
 128         INIT_LIST_HEAD(&sdp->sd_ail1_list);
 129         INIT_LIST_HEAD(&sdp->sd_ail2_list);
 130
 131         init_rwsem(&sdp->sd_log_flush_lock);
 132         atomic_set(&sdp->sd_log_in_flight, 0);
 133         atomic_set(&sdp->sd_reserving_log, 0);
 134         init_waitqueue_head(&sdp->sd_reserving_log_wait);
 135         init_waitqueue_head(&sdp->sd_log_flush_wait);
 136         atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 137         mutex_init(&sdp->sd_freeze_mutex);
 138
 139         return sdp;
 140 }
 141
 142
 143 /**
 144  * gfs2_check_sb - Check superblock
 145  * @sdp: the filesystem
 146  * @sb: The superblock
 147  * @silent: Don't print a message if the check fails
 148  *
 149  * Checks the version code of the FS is one that we understand how to
 150  * read and that the sizes of the various on-disk structures have not
 151  * changed.
 152  */
 153
 154 static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
 155 {
 156         struct gfs2_sb_host *sb = &sdp->sd_sb;
 157
 158         if (sb->sb_magic != GFS2_MAGIC ||
 159             sb->sb_type != GFS2_METATYPE_SB) {
 160                 if (!silent)
 161                         pr_warn("not a GFS2 filesystem\n");
 162                 return -EINVAL;
 163         }
 164
 165         /*  If format numbers match exactly, we're done.  */
 166
 167         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 168             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 169                 return 0;
 170
 171         fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
 172
 173         return -EINVAL;
 174 }
 175
 176 static void end_bio_io_page(struct bio *bio)
 177 {
 178         struct page *page = bio->bi_private;
 179
 180         if (!bio->bi_status)
 181                 SetPageUptodate(page);
 182         else
 183                 pr_warn("error %d reading superblock\n", bio->bi_status);
 184         unlock_page(page);
 185 }
 186
 187 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
 188 {
 189         struct gfs2_sb_host *sb = &sdp->sd_sb;
 190         struct super_block *s = sdp->sd_vfs;
 191         const struct gfs2_sb *str = buf;
 192
 193         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 194         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 195         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 196         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 197         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 198         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 199         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 200         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 201         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 202         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 203         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 204
 205         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 206         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 207         memcpy(&s->s_uuid, str->sb_uuid, 16);
 208 }
 209
 210 /**
 211  * gfs2_read_super - Read the gfs2 super block from disk
 212  * @sdp: The GFS2 super block
 213  * @sector: The location of the super block
 214  * @error: The error code to return
 215  *
 216  * This uses the bio functions to read the super block from disk
 217  * because we want to be 100% sure that we never read cached data.
 218  * A super block is read twice only during each GFS2 mount and is
 219  * never written to by the filesystem. The first time its read no
 220  * locks are held, and the only details which are looked at are those
 221  * relating to the locking protocol. Once locking is up and working,
 222  * the sb is read again under the lock to establish the location of
 223  * the master directory (contains pointers to journals etc) and the
 224  * root directory.
 225  *
 226  * Returns: 0 on success or error
 227  */
 228
 229 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
 230 {
 231         struct super_block *sb = sdp->sd_vfs;
 232         struct gfs2_sb *p;
 233         struct page *page;
 234         struct bio *bio;
 235
 236         page = alloc_page(GFP_NOFS);
 237         if (unlikely(!page))
 238                 return -ENOMEM;
 239
 240         ClearPageUptodate(page);
 241         ClearPageDirty(page);
 242         lock_page(page);
 243
 244         bio = bio_alloc(GFP_NOFS, 1);
 245         bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
 246         bio_set_dev(bio, sb->s_bdev);
 247         bio_add_page(bio, page, PAGE_SIZE, 0);
 248
 249         bio->bi_end_io = end_bio_io_page;
 250         bio->bi_private = page;
 251         bio_set_op_attrs(bio, REQ_OP_READ, REQ_META);
 252         submit_bio(bio);
 253         wait_on_page_locked(page);
 254         bio_put(bio);
 255         if (!PageUptodate(page)) {
 256                 __free_page(page);
 257                 return -EIO;
 258         }
 259         p = kmap(page);
 260         gfs2_sb_in(sdp, p);
 261         kunmap(page);
 262         __free_page(page);
 263         return gfs2_check_sb(sdp, silent);
 264 }
 265
 266 /**
 267  * gfs2_read_sb - Read super block
 268  * @sdp: The GFS2 superblock
 269  * @silent: Don't print message if mount fails
 270  *
 271  */
 272
 273 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
 274 {
 275         u32 hash_blocks, ind_blocks, leaf_blocks;
 276         u32 tmp_blocks;
 277         unsigned int x;
 278         int error;
 279
 280         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 281         if (error) {
 282                 if (!silent)
 283                         fs_err(sdp, "can't read superblock\n");
 284                 return error;
 285         }
 286
 287         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 288                                GFS2_BASIC_BLOCK_SHIFT;
 289         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
 290         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 291                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 292         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 293                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 294         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 295         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 296         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 297         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 298         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 299                                 sizeof(struct gfs2_meta_header)) /
 300                                 sizeof(struct gfs2_quota_change);
 301         sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
 302                                      sizeof(struct gfs2_meta_header))
 303                 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
 304
 305         /* Compute maximum reservation required to add a entry to a directory */
 306
 307         hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
 308                              sdp->sd_jbsize);
 309
 310         ind_blocks = 0;
 311         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 312                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 313                 ind_blocks += tmp_blocks;
 314         }
 315
 316         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 317
 318         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 319
 320         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 321                                 sizeof(struct gfs2_dinode);
 322         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 323         for (x = 2;; x++) {
 324                 u64 space, d;
 325                 u32 m;
 326
 327                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 328                 d = space;
 329                 m = do_div(d, sdp->sd_inptrs);
 330
 331                 if (d != sdp->sd_heightsize[x - 1] || m)
 332                         break;
 333                 sdp->sd_heightsize[x] = space;
 334         }
 335         sdp->sd_max_height = x;
 336         sdp->sd_heightsize[x] = ~0;
 337         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 338
 339         sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
 340                                       sizeof(struct gfs2_leaf)) /
 341                                      GFS2_MIN_DIRENT_SIZE;
 342         return 0;
 343 }
 344
 345 static int init_names(struct gfs2_sbd *sdp, int silent)
 346 {
 347         char *proto, *table;
 348         int error = 0;
 349
 350         proto = sdp->sd_args.ar_lockproto;
 351         table = sdp->sd_args.ar_locktable;
 352
 353         /*  Try to autodetect  */
 354
 355         if (!proto[0] || !table[0]) {
 356                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 357                 if (error)
 358                         return error;
 359
 360                 if (!proto[0])
 361                         proto = sdp->sd_sb.sb_lockproto;
 362                 if (!table[0])
 363                         table = sdp->sd_sb.sb_locktable;
 364         }
 365
 366         if (!table[0])
 367                 table = sdp->sd_vfs->s_id;
 368
 369         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
 370         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
 371
 372         table = sdp->sd_table_name;
 373         while ((table = strchr(table, '/')))
 374                 *table = '_';
 375
 376         return error;
 377 }
 378
 379 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
 380                         int undo)
 381 {
 382         int error = 0;
 383
 384         if (undo)
 385                 goto fail_trans;
 386
 387         error = gfs2_glock_nq_num(sdp,
 388                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
 389                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
 390                                   mount_gh);
 391         if (error) {
 392                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
 393                 goto fail;
 394         }
 395
 396         error = gfs2_glock_nq_num(sdp,
 397                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
 398                                   LM_ST_SHARED,
 399                                   LM_FLAG_NOEXP | GL_EXACT,
 400                                   &sdp->sd_live_gh);
 401         if (error) {
 402                 fs_err(sdp, "can't acquire live glock: %d\n", error);
 403                 goto fail_mount;
 404         }
 405
 406         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
 407                                CREATE, &sdp->sd_rename_gl);
 408         if (error) {
 409                 fs_err(sdp, "can't create rename glock: %d\n", error);
 410                 goto fail_live;
 411         }
 412
 413         error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
 414                                CREATE, &sdp->sd_freeze_gl);
 415         if (error) {
 416                 fs_err(sdp, "can't create transaction glock: %d\n", error);
 417                 goto fail_rename;
 418         }
 419
 420         return 0;
 421
 422 fail_trans:
 423         gfs2_glock_put(sdp->sd_freeze_gl);
 424 fail_rename:
 425         gfs2_glock_put(sdp->sd_rename_gl);
 426 fail_live:
 427         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 428 fail_mount:
 429         gfs2_glock_dq_uninit(mount_gh);
 430 fail:
 431         return error;
 432 }
 433
 434 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
 435                             u64 no_addr, const char *name)
 436 {
 437         struct gfs2_sbd *sdp = sb->s_fs_info;
 438         struct dentry *dentry;
 439         struct inode *inode;
 440
 441         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
 442                                   GFS2_BLKST_FREE /* ignore */);
 443         if (IS_ERR(inode)) {
 444                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
 445                 return PTR_ERR(inode);
 446         }
 447         dentry = d_make_root(inode);
 448         if (!dentry) {
 449                 fs_err(sdp, "can't alloc %s dentry\n", name);
 450                 return -ENOMEM;
 451         }
 452         *dptr = dentry;
 453         return 0;
 454 }
 455
 456 static int init_sb(struct gfs2_sbd *sdp, int silent)
 457 {
 458         struct super_block *sb = sdp->sd_vfs;
 459         struct gfs2_holder sb_gh;
 460         u64 no_addr;
 461         int ret;
 462
 463         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
 464                                 LM_ST_SHARED, 0, &sb_gh);
 465         if (ret) {
 466                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
 467                 return ret;
 468         }
 469
 470         ret = gfs2_read_sb(sdp, silent);
 471         if (ret) {
 472                 fs_err(sdp, "can't read superblock: %d\n", ret);
 473                 goto out;
 474         }
 475
 476         /* Set up the buffer cache and SB for real */
 477         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
 478                 ret = -EINVAL;
 479                 fs_err(sdp, "FS block size (%u) is too small for device "
 480                        "block size (%u)\n",
 481                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
 482                 goto out;
 483         }
 484         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
 485                 ret = -EINVAL;
 486                 fs_err(sdp, "FS block size (%u) is too big for machine "
 487                        "page size (%u)\n",
 488                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
 489                 goto out;
 490         }
 491         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
 492
 493         /* Get the root inode */
 494         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
 495         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
 496         if (ret)
 497                 goto out;
 498
 499         /* Get the master inode */
 500         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
 501         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
 502         if (ret) {
 503                 dput(sdp->sd_root_dir);
 504                 goto out;
 505         }
 506         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
 507 out:
 508         gfs2_glock_dq_uninit(&sb_gh);
 509         return ret;
 510 }
 511
 512 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
 513 {
 514         char *message = "FIRSTMOUNT=Done";
 515         char *envp[] = { message, NULL };
 516
 517         fs_info(sdp, "first mount done, others may mount\n");
 518
 519         if (sdp->sd_lockstruct.ls_ops->lm_first_done)
 520                 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
 521
 522         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 523 }
 524
 525 /**
 526  * gfs2_jindex_hold - Grab a lock on the jindex
 527  * @sdp: The GFS2 superblock
 528  * @ji_gh: the holder for the jindex glock
 529  *
 530  * Returns: errno
 531  */
 532
 533 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 534 {
 535         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 536         struct qstr name;
 537         char buf[20];
 538         struct gfs2_jdesc *jd;
 539         int error;
 540
 541         name.name = buf;
 542
 543         mutex_lock(&sdp->sd_jindex_mutex);
 544
 545         for (;;) {
 546                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 547                 if (error)
 548                         break;
 549
 550                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 551                 name.hash = gfs2_disk_hash(name.name, name.len);
 552
 553                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 554                 if (error == -ENOENT) {
 555                         error = 0;
 556                         break;
 557                 }
 558
 559                 gfs2_glock_dq_uninit(ji_gh);
 560
 561                 if (error)
 562                         break;
 563
 564                 error = -ENOMEM;
 565                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 566                 if (!jd)
 567                         break;
 568
 569                 INIT_LIST_HEAD(&jd->extent_list);
 570                 INIT_LIST_HEAD(&jd->jd_revoke_list);
 571
 572                 INIT_WORK(&jd->jd_work, gfs2_recover_func);
 573                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
 574                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 575                         if (!jd->jd_inode)
 576                                 error = -ENOENT;
 577                         else
 578                                 error = PTR_ERR(jd->jd_inode);
 579                         kfree(jd);
 580                         break;
 581                 }
 582
 583                 spin_lock(&sdp->sd_jindex_spin);
 584                 jd->jd_jid = sdp->sd_journals++;
 585                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 586                 spin_unlock(&sdp->sd_jindex_spin);
 587         }
 588
 589         mutex_unlock(&sdp->sd_jindex_mutex);
 590
 591         return error;
 592 }
 593
 594 /**
 595  * check_journal_clean - Make sure a journal is clean for a spectator mount
 596  * @sdp: The GFS2 superblock
 597  * @jd: The journal descriptor
 598  *
 599  * Returns: 0 if the journal is clean or locked, else an error
 600  */
 601 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
 602 {
 603         int error;
 604         struct gfs2_holder j_gh;
 605         struct gfs2_log_header_host head;
 606         struct gfs2_inode *ip;
 607
 608         ip = GFS2_I(jd->jd_inode);
 609         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
 610                                    GL_EXACT | GL_NOCACHE, &j_gh);
 611         if (error) {
 612                 fs_err(sdp, "Error locking journal for spectator mount.\n");
 613                 return -EPERM;
 614         }
 615         error = gfs2_jdesc_check(jd);
 616         if (error) {
 617                 fs_err(sdp, "Error checking journal for spectator mount.\n");
 618                 goto out_unlock;
 619         }
 620         error = gfs2_find_jhead(jd, &head);
 621         if (error) {
 622                 fs_err(sdp, "Error parsing journal for spectator mount.\n");
 623                 goto out_unlock;
 624         }
 625         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 626                 error = -EPERM;
 627                 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
 628                        "must not be a spectator.\n", jd->jd_jid);
 629         }
 630
 631 out_unlock:
 632         gfs2_glock_dq_uninit(&j_gh);
 633         return error;
 634 }
 635
 636 static int init_journal(struct gfs2_sbd *sdp, int undo)
 637 {
 638         struct inode *master = d_inode(sdp->sd_master_dir);
 639         struct gfs2_holder ji_gh;
 640         struct gfs2_inode *ip;
 641         int jindex = 1;
 642         int error = 0;
 643
 644         if (undo) {
 645                 jindex = 0;
 646                 goto fail_jinode_gh;
 647         }
 648
 649         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
 650         if (IS_ERR(sdp->sd_jindex)) {
 651                 fs_err(sdp, "can't lookup journal index: %d\n", error);
 652                 return PTR_ERR(sdp->sd_jindex);
 653         }
 654
 655         /* Load in the journal index special file */
 656
 657         error = gfs2_jindex_hold(sdp, &ji_gh);
 658         if (error) {
 659                 fs_err(sdp, "can't read journal index: %d\n", error);
 660                 goto fail;
 661         }
 662
 663         error = -EUSERS;
 664         if (!gfs2_jindex_size(sdp)) {
 665                 fs_err(sdp, "no journals!\n");
 666                 goto fail_jindex;
 667         }
 668
 669         atomic_set(&sdp->sd_log_blks_needed, 0);
 670         if (sdp->sd_args.ar_spectator) {
 671                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
 672                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 673                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 674                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 675         } else {
 676                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
 677                         fs_err(sdp, "can't mount journal #%u\n",
 678                                sdp->sd_lockstruct.ls_jid);
 679                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
 680                                gfs2_jindex_size(sdp),
 681                                gfs2_jindex_size(sdp) - 1);
 682                         goto fail_jindex;
 683                 }
 684                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
 685
 686                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
 687                                           &gfs2_journal_glops,
 688                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
 689                                           &sdp->sd_journal_gh);
 690                 if (error) {
 691                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
 692                         goto fail_jindex;
 693                 }
 694
 695                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 696                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 697                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
 698                                            &sdp->sd_jinode_gh);
 699                 if (error) {
 700                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
 701                                error);
 702                         goto fail_journal_gh;
 703                 }
 704
 705                 error = gfs2_jdesc_check(sdp->sd_jdesc);
 706                 if (error) {
 707                         fs_err(sdp, "my journal (%u) is bad: %d\n",
 708                                sdp->sd_jdesc->jd_jid, error);
 709                         goto fail_jinode_gh;
 710                 }
 711                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 712                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 713                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 714
 715                 /* Map the extents for this journal's blocks */
 716                 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
 717         }
 718         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
 719
 720         if (sdp->sd_lockstruct.ls_first) {
 721                 unsigned int x;
 722                 for (x = 0; x < sdp->sd_journals; x++) {
 723                         struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
 724
 725                         if (sdp->sd_args.ar_spectator) {
 726                                 error = check_journal_clean(sdp, jd);
 727                                 if (error)
 728                                         goto fail_jinode_gh;
 729                                 continue;
 730                         }
 731                         error = gfs2_recover_journal(jd, true);
 732                         if (error) {
 733                                 fs_err(sdp, "error recovering journal %u: %d\n",
 734                                        x, error);
 735                                 goto fail_jinode_gh;
 736                         }
 737                 }
 738
 739                 gfs2_others_may_mount(sdp);
 740         } else if (!sdp->sd_args.ar_spectator) {
 741                 error = gfs2_recover_journal(sdp->sd_jdesc, true);
 742                 if (error) {
 743                         fs_err(sdp, "error recovering my journal: %d\n", error);
 744                         goto fail_jinode_gh;
 745                 }
 746         }
 747
 748         sdp->sd_log_idle = 1;
 749         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
 750         gfs2_glock_dq_uninit(&ji_gh);
 751         jindex = 0;
 752         INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
 753         return 0;
 754
 755 fail_jinode_gh:
 756         if (!sdp->sd_args.ar_spectator)
 757                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 758 fail_journal_gh:
 759         if (!sdp->sd_args.ar_spectator)
 760                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 761 fail_jindex:
 762         gfs2_jindex_free(sdp);
 763         if (jindex)
 764                 gfs2_glock_dq_uninit(&ji_gh);
 765 fail:
 766         iput(sdp->sd_jindex);
 767         return error;
 768 }
 769
 770 static struct lock_class_key gfs2_quota_imutex_key;
 771
 772 static int init_inodes(struct gfs2_sbd *sdp, int undo)
 773 {
 774         int error = 0;
 775         struct inode *master = d_inode(sdp->sd_master_dir);
 776
 777         if (undo)
 778                 goto fail_qinode;
 779
 780         error = init_journal(sdp, undo);
 781         complete_all(&sdp->sd_journal_ready);
 782         if (error)
 783                 goto fail;
 784
 785         /* Read in the master statfs inode */
 786         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
 787         if (IS_ERR(sdp->sd_statfs_inode)) {
 788                 error = PTR_ERR(sdp->sd_statfs_inode);
 789                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
 790                 goto fail_journal;
 791         }
 792
 793         /* Read in the resource index inode */
 794         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
 795         if (IS_ERR(sdp->sd_rindex)) {
 796                 error = PTR_ERR(sdp->sd_rindex);
 797                 fs_err(sdp, "can't get resource index inode: %d\n", error);
 798                 goto fail_statfs;
 799         }
 800         sdp->sd_rindex_uptodate = 0;
 801
 802         /* Read in the quota inode */
 803         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
 804         if (IS_ERR(sdp->sd_quota_inode)) {
 805                 error = PTR_ERR(sdp->sd_quota_inode);
 806                 fs_err(sdp, "can't get quota file inode: %d\n", error);
 807                 goto fail_rindex;
 808         }
 809         /*
 810          * i_rwsem on quota files is special. Since this inode is hidden system
 811          * file, we are safe to define locking ourselves.
 812          */
 813         lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
 814                           &gfs2_quota_imutex_key);
 815
 816         error = gfs2_rindex_update(sdp);
 817         if (error)
 818                 goto fail_qinode;
 819
 820         return 0;
 821
 822 fail_qinode:
 823         iput(sdp->sd_quota_inode);
 824 fail_rindex:
 825         gfs2_clear_rgrpd(sdp);
 826         iput(sdp->sd_rindex);
 827 fail_statfs:
 828         iput(sdp->sd_statfs_inode);
 829 fail_journal:
 830         init_journal(sdp, UNDO);
 831 fail:
 832         return error;
 833 }
 834
 835 static int init_per_node(struct gfs2_sbd *sdp, int undo)
 836 {
 837         struct inode *pn = NULL;
 838         char buf[30];
 839         int error = 0;
 840         struct gfs2_inode *ip;
 841         struct inode *master = d_inode(sdp->sd_master_dir);
 842
 843         if (sdp->sd_args.ar_spectator)
 844                 return 0;
 845
 846         if (undo)
 847                 goto fail_qc_gh;
 848
 849         pn = gfs2_lookup_simple(master, "per_node");
 850         if (IS_ERR(pn)) {
 851                 error = PTR_ERR(pn);
 852                 fs_err(sdp, "can't find per_node directory: %d\n", error);
 853                 return error;
 854         }
 855
 856         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
 857         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
 858         if (IS_ERR(sdp->sd_sc_inode)) {
 859                 error = PTR_ERR(sdp->sd_sc_inode);
 860                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
 861                 goto fail;
 862         }
 863
 864         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
 865         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
 866         if (IS_ERR(sdp->sd_qc_inode)) {
 867                 error = PTR_ERR(sdp->sd_qc_inode);
 868                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
 869                 goto fail_ut_i;
 870         }
 871
 872         iput(pn);
 873         pn = NULL;
 874
 875         ip = GFS2_I(sdp->sd_sc_inode);
 876         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 877                                    &sdp->sd_sc_gh);
 878         if (error) {
 879                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
 880                 goto fail_qc_i;
 881         }
 882
 883         ip = GFS2_I(sdp->sd_qc_inode);
 884         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 885                                    &sdp->sd_qc_gh);
 886         if (error) {
 887                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
 888                 goto fail_ut_gh;
 889         }
 890
 891         return 0;
 892
 893 fail_qc_gh:
 894         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 895 fail_ut_gh:
 896         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 897 fail_qc_i:
 898         iput(sdp->sd_qc_inode);
 899 fail_ut_i:
 900         iput(sdp->sd_sc_inode);
 901 fail:
 902         iput(pn);
 903         return error;
 904 }
 905
 906 static const match_table_t nolock_tokens = {
 907         { Opt_jid, "jid=%d\n", },
 908         { Opt_err, NULL },
 909 };
 910
 911 static const struct lm_lockops nolock_ops = {
 912         .lm_proto_name = "lock_nolock",
 913         .lm_put_lock = gfs2_glock_free,
 914         .lm_tokens = &nolock_tokens,
 915 };
 916
 917 /**
 918  * gfs2_lm_mount - mount a locking protocol
 919  * @sdp: the filesystem
 920  * @args: mount arguments
 921  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
 922  *
 923  * Returns: errno
 924  */
 925
 926 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 927 {
 928         const struct lm_lockops *lm;
 929         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 930         struct gfs2_args *args = &sdp->sd_args;
 931         const char *proto = sdp->sd_proto_name;
 932         const char *table = sdp->sd_table_name;
 933         char *o, *options;
 934         int ret;
 935
 936         if (!strcmp("lock_nolock", proto)) {
 937                 lm = &nolock_ops;
 938                 sdp->sd_args.ar_localflocks = 1;
 939 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
 940         } else if (!strcmp("lock_dlm", proto)) {
 941                 lm = &gfs2_dlm_ops;
 942 #endif
 943         } else {
 944                 pr_info("can't find protocol %s\n", proto);
 945                 return -ENOENT;
 946         }
 947
 948         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
 949
 950         ls->ls_ops = lm;
 951         ls->ls_first = 1;
 952
 953         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
 954                 substring_t tmp[MAX_OPT_ARGS];
 955                 int token, option;
 956
 957                 if (!o || !*o)
 958                         continue;
 959
 960                 token = match_token(o, *lm->lm_tokens, tmp);
 961                 switch (token) {
 962                 case Opt_jid:
 963                         ret = match_int(&tmp[0], &option);
 964                         if (ret || option < 0)
 965                                 goto hostdata_error;
 966                         if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
 967                                 ls->ls_jid = option;
 968                         break;
 969                 case Opt_id:
 970                 case Opt_nodir:
 971                         /* Obsolete, but left for backward compat purposes */
 972                         break;
 973                 case Opt_first:
 974                         ret = match_int(&tmp[0], &option);
 975                         if (ret || (option != 0 && option != 1))
 976                                 goto hostdata_error;
 977                         ls->ls_first = option;
 978                         break;
 979                 case Opt_err:
 980                 default:
 981 hostdata_error:
 982                         fs_info(sdp, "unknown hostdata (%s)\n", o);
 983                         return -EINVAL;
 984                 }
 985         }
 986
 987         if (lm->lm_mount == NULL) {
 988                 fs_info(sdp, "Now mounting FS...\n");
 989                 complete_all(&sdp->sd_locking_init);
 990                 return 0;
 991         }
 992         ret = lm->lm_mount(sdp, table);
 993         if (ret == 0)
 994                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
 995         complete_all(&sdp->sd_locking_init);
 996         return ret;
 997 }
 998
 999 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1000 {
1001         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1002         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1003             lm->lm_unmount)
1004                 lm->lm_unmount(sdp);
1005 }
1006
1007 static int wait_on_journal(struct gfs2_sbd *sdp)
1008 {
1009         if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
1010                 return 0;
1011
1012         return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
1013                 ? -EINTR : 0;
1014 }
1015
1016 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1017 {
1018         struct super_block *sb = sdp->sd_vfs;
1019         char ro[20];
1020         char spectator[20];
1021         char *envp[] = { ro, spectator, NULL };
1022         sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
1023         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1024         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1025 }
1026
1027 /**
1028  * fill_super - Read in superblock
1029  * @sb: The VFS superblock
1030  * @data: Mount options
1031  * @silent: Don't complain if it's not a GFS2 filesystem
1032  *
1033  * Returns: errno
1034  */
1035
1036 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1037 {
1038         struct gfs2_sbd *sdp;
1039         struct gfs2_holder mount_gh;
1040         int error;
1041
1042         sdp = init_sbd(sb);
1043         if (!sdp) {
1044                 pr_warn("can't alloc struct gfs2_sbd\n");
1045                 return -ENOMEM;
1046         }
1047         sdp->sd_args = *args;
1048
1049         if (sdp->sd_args.ar_spectator) {
1050                 sb->s_flags |= SB_RDONLY;
1051                 set_bit(SDF_RORECOVERY, &sdp->sd_flags);
1052         }
1053         if (sdp->sd_args.ar_posix_acl)
1054                 sb->s_flags |= SB_POSIXACL;
1055         if (sdp->sd_args.ar_nobarrier)
1056                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1057
1058         sb->s_flags |= SB_NOSEC;
1059         sb->s_magic = GFS2_MAGIC;
1060         sb->s_op = &gfs2_super_ops;
1061         sb->s_d_op = &gfs2_dops;
1062         sb->s_export_op = &gfs2_export_ops;
1063         sb->s_xattr = gfs2_xattr_handlers;
1064         sb->s_qcop = &gfs2_quotactl_ops;
1065         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1066         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1067         sb->s_time_gran = 1;
1068         sb->s_maxbytes = MAX_LFS_FILESIZE;
1069
1070         /* Set up the buffer cache and fill in some fake block size values
1071            to allow us to read-in the on-disk superblock. */
1072         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1073         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1074         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1075                                GFS2_BASIC_BLOCK_SHIFT;
1076         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
1077
1078         sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
1079         sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1080         if (sdp->sd_args.ar_statfs_quantum) {
1081                 sdp->sd_tune.gt_statfs_slow = 0;
1082                 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1083         } else {
1084                 sdp->sd_tune.gt_statfs_slow = 1;
1085                 sdp->sd_tune.gt_statfs_quantum = 30;
1086         }
1087
1088         error = init_names(sdp, silent);
1089         if (error) {
1090                 /* In this case, we haven't initialized sysfs, so we have to
1091                    manually free the sdp. */
1092                 free_percpu(sdp->sd_lkstats);
1093                 kfree(sdp);
1094                 sb->s_fs_info = NULL;
1095                 return error;
1096         }
1097
1098         snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
1099
1100         error = gfs2_sys_fs_add(sdp);
1101         /*
1102          * If we hit an error here, gfs2_sys_fs_add will have called function
1103          * kobject_put which causes the sysfs usage count to go to zero, which
1104          * causes sysfs to call function gfs2_sbd_release, which frees sdp.
1105          * Subsequent error paths here will call gfs2_sys_fs_del, which also
1106          * kobject_put to free sdp.
1107          */
1108         if (error)
1109                 return error;
1110
1111         gfs2_create_debugfs_file(sdp);
1112
1113         error = gfs2_lm_mount(sdp, silent);
1114         if (error)
1115                 goto fail_debug;
1116
1117         error = init_locking(sdp, &mount_gh, DO);
1118         if (error)
1119                 goto fail_lm;
1120
1121         error = init_sb(sdp, silent);
1122         if (error)
1123                 goto fail_locking;
1124
1125         error = wait_on_journal(sdp);
1126         if (error)
1127                 goto fail_sb;
1128
1129         /*
1130          * If user space has failed to join the cluster or some similar
1131          * failure has occurred, then the journal id will contain a
1132          * negative (error) number. This will then be returned to the
1133          * caller (of the mount syscall). We do this even for spectator
1134          * mounts (which just write a jid of 0 to indicate "ok" even though
1135          * the jid is unused in the spectator case)
1136          */
1137         if (sdp->sd_lockstruct.ls_jid < 0) {
1138                 error = sdp->sd_lockstruct.ls_jid;
1139                 sdp->sd_lockstruct.ls_jid = 0;
1140                 goto fail_sb;
1141         }
1142
1143         if (sdp->sd_args.ar_spectator)
1144                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
1145                          sdp->sd_table_name);
1146         else
1147                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
1148                          sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
1149
1150         error = init_inodes(sdp, DO);
1151         if (error)
1152                 goto fail_sb;
1153
1154         error = init_per_node(sdp, DO);
1155         if (error)
1156                 goto fail_inodes;
1157
1158         error = gfs2_statfs_init(sdp);
1159         if (error) {
1160                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1161                 goto fail_per_node;
1162         }
1163
1164         if (!sb_rdonly(sb)) {
1165                 error = gfs2_make_fs_rw(sdp);
1166                 if (error) {
1167                         fs_err(sdp, "can't make FS RW: %d\n", error);
1168                         goto fail_per_node;
1169                 }
1170         }
1171
1172         gfs2_glock_dq_uninit(&mount_gh);
1173         gfs2_online_uevent(sdp);
1174         return 0;
1175
1176 fail_per_node:
1177         init_per_node(sdp, UNDO);
1178 fail_inodes:
1179         init_inodes(sdp, UNDO);
1180 fail_sb:
1181         if (sdp->sd_root_dir)
1182                 dput(sdp->sd_root_dir);
1183         if (sdp->sd_master_dir)
1184                 dput(sdp->sd_master_dir);
1185         if (sb->s_root)
1186                 dput(sb->s_root);
1187         sb->s_root = NULL;
1188 fail_locking:
1189         init_locking(sdp, &mount_gh, UNDO);
1190 fail_lm:
1191         complete_all(&sdp->sd_journal_ready);
1192         gfs2_gl_hash_clear(sdp);
1193         gfs2_lm_unmount(sdp);
1194 fail_debug:
1195         gfs2_delete_debugfs_file(sdp);
1196         free_percpu(sdp->sd_lkstats);
1197         /* gfs2_sys_fs_del must be the last thing we do, since it causes
1198          * sysfs to call function gfs2_sbd_release, which frees sdp. */
1199         gfs2_sys_fs_del(sdp);
1200         sb->s_fs_info = NULL;
1201         return error;
1202 }
1203
1204 static int set_gfs2_super(struct super_block *s, void *data)
1205 {
1206         s->s_bdev = data;
1207         s->s_dev = s->s_bdev->bd_dev;
1208         s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
1209         return 0;
1210 }
1211
1212 static int test_gfs2_super(struct super_block *s, void *ptr)
1213 {
1214         struct block_device *bdev = ptr;
1215         return (bdev == s->s_bdev);
1216 }
1217
1218 /**
1219  * gfs2_mount - Get the GFS2 superblock
1220  * @fs_type: The GFS2 filesystem type
1221  * @flags: Mount flags
1222  * @dev_name: The name of the device
1223  * @data: The mount arguments
1224  *
1225  * Q. Why not use get_sb_bdev() ?
1226  * A. We need to select one of two root directories to mount, independent
1227  *    of whether this is the initial, or subsequent, mount of this sb
1228  *
1229  * Returns: 0 or -ve on error
1230  */
1231
1232 static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
1233                        const char *dev_name, void *data)
1234 {
1235         struct block_device *bdev;
1236         struct super_block *s;
1237         fmode_t mode = FMODE_READ | FMODE_EXCL;
1238         int error;
1239         struct gfs2_args args;
1240         struct gfs2_sbd *sdp;
1241
1242         if (!(flags & SB_RDONLY))
1243                 mode |= FMODE_WRITE;
1244
1245         bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1246         if (IS_ERR(bdev))
1247                 return ERR_CAST(bdev);
1248
1249         /*
1250          * once the super is inserted into the list by sget, s_umount
1251          * will protect the lockfs code from trying to start a snapshot
1252          * while we are mounting
1253          */
1254         mutex_lock(&bdev->bd_fsfreeze_mutex);
1255         if (bdev->bd_fsfreeze_count > 0) {
1256                 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1257                 error = -EBUSY;
1258                 goto error_bdev;
1259         }
1260         s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
1261         mutex_unlock(&bdev->bd_fsfreeze_mutex);
1262         error = PTR_ERR(s);
1263         if (IS_ERR(s))
1264                 goto error_bdev;
1265
1266         if (s->s_root) {
1267                 /*
1268                  * s_umount nests inside bd_mutex during
1269                  * __invalidate_device().  blkdev_put() acquires
1270                  * bd_mutex and can't be called under s_umount.  Drop
1271                  * s_umount temporarily.  This is safe as we're
1272                  * holding an active reference.
1273                  */
1274                 up_write(&s->s_umount);
1275                 blkdev_put(bdev, mode);
1276                 down_write(&s->s_umount);
1277         } else {
1278                 /* s_mode must be set before deactivate_locked_super calls */
1279                 s->s_mode = mode;
1280         }
1281
1282         memset(&args, 0, sizeof(args));
1283         args.ar_quota = GFS2_QUOTA_DEFAULT;
1284         args.ar_data = GFS2_DATA_DEFAULT;
1285         args.ar_commit = 30;
1286         args.ar_statfs_quantum = 30;
1287         args.ar_quota_quantum = 60;
1288         args.ar_errors = GFS2_ERRORS_DEFAULT;
1289
1290         error = gfs2_mount_args(&args, data);
1291         if (error) {
1292                 pr_warn("can't parse mount arguments\n");
1293                 goto error_super;
1294         }
1295
1296         if (s->s_root) {
1297                 error = -EBUSY;
1298                 if ((flags ^ s->s_flags) & SB_RDONLY)
1299                         goto error_super;
1300         } else {
1301                 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1302                 sb_set_blocksize(s, block_size(bdev));
1303                 error = fill_super(s, &args, flags & SB_SILENT ? 1 : 0);
1304                 if (error)
1305                         goto error_super;
1306                 s->s_flags |= SB_ACTIVE;
1307                 bdev->bd_super = s;
1308         }
1309
1310         sdp = s->s_fs_info;
1311         if (args.ar_meta)
1312                 return dget(sdp->sd_master_dir);
1313         else
1314                 return dget(sdp->sd_root_dir);
1315
1316 error_super:
1317         deactivate_locked_super(s);
1318         return ERR_PTR(error);
1319 error_bdev:
1320         blkdev_put(bdev, mode);
1321         return ERR_PTR(error);
1322 }
1323
1324 static int set_meta_super(struct super_block *s, void *ptr)
1325 {
1326         return -EINVAL;
1327 }
1328
1329 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1330                         int flags, const char *dev_name, void *data)
1331 {
1332         struct super_block *s;
1333         struct gfs2_sbd *sdp;
1334         struct path path;
1335         int error;
1336
1337         if (!dev_name || !*dev_name)
1338                 return ERR_PTR(-EINVAL);
1339
1340         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1341         if (error) {
1342                 pr_warn("path_lookup on %s returned error %d\n",
1343                         dev_name, error);
1344                 return ERR_PTR(error);
1345         }
1346         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1347                  path.dentry->d_sb->s_bdev);
1348         path_put(&path);
1349         if (IS_ERR(s)) {
1350                 pr_warn("gfs2 mount does not exist\n");
1351                 return ERR_CAST(s);
1352         }
1353         if ((flags ^ s->s_flags) & SB_RDONLY) {
1354                 deactivate_locked_super(s);
1355                 return ERR_PTR(-EBUSY);
1356         }
1357         sdp = s->s_fs_info;
1358         return dget(sdp->sd_master_dir);
1359 }
1360
1361 static void gfs2_kill_sb(struct super_block *sb)
1362 {
1363         struct gfs2_sbd *sdp = sb->s_fs_info;
1364
1365         if (sdp == NULL) {
1366                 kill_block_super(sb);
1367                 return;
1368         }
1369
1370         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SYNC | GFS2_LFC_KILL_SB);
1371         dput(sdp->sd_root_dir);
1372         dput(sdp->sd_master_dir);
1373         sdp->sd_root_dir = NULL;
1374         sdp->sd_master_dir = NULL;
1375         shrink_dcache_sb(sb);
1376         free_percpu(sdp->sd_lkstats);
1377         kill_block_super(sb);
1378 }
1379
1380 struct file_system_type gfs2_fs_type = {
1381         .name = "gfs2",
1382         .fs_flags = FS_REQUIRES_DEV,
1383         .mount = gfs2_mount,
1384         .kill_sb = gfs2_kill_sb,
1385         .owner = THIS_MODULE,
1386 };
1387 MODULE_ALIAS_FS("gfs2");
1388
1389 struct file_system_type gfs2meta_fs_type = {
1390         .name = "gfs2meta",
1391         .fs_flags = FS_REQUIRES_DEV,
1392         .mount = gfs2_mount_meta,
1393         .owner = THIS_MODULE,
1394 };
1395 MODULE_ALIAS_FS("gfs2meta");