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         sdp->sd_vfs = sb;
  76         sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
  77         if (!sdp->sd_lkstats) {
  78                 kfree(sdp);
  79                 return NULL;
  80         }
  81         sb->s_fs_info = sdp;
  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 (sb->sb_fs_format != GFS2_FORMAT_FS ||
 165             sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
 166                 fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
 167                 return -EINVAL;
 168         }
 169
 170         if (sb->sb_bsize < 512 || sb->sb_bsize > PAGE_SIZE ||
 171             (sb->sb_bsize & (sb->sb_bsize - 1))) {
 172                 pr_warn("Invalid superblock size\n");
 173                 return -EINVAL;
 174         }
 175         if (sb->sb_bsize_shift != ffs(sb->sb_bsize) - 1) {
 176                 pr_warn("Invalid block size shift\n");
 177                 return -EINVAL;
 178         }
 179         return 0;
 180 }
 181
 182 static void end_bio_io_page(struct bio *bio)
 183 {
 184         struct page *page = bio->bi_private;
 185
 186         if (!bio->bi_status)
 187                 SetPageUptodate(page);
 188         else
 189                 pr_warn("error %d reading superblock\n", bio->bi_status);
 190         unlock_page(page);
 191 }
 192
 193 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
 194 {
 195         struct gfs2_sb_host *sb = &sdp->sd_sb;
 196         struct super_block *s = sdp->sd_vfs;
 197         const struct gfs2_sb *str = buf;
 198
 199         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 200         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 201         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 202         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 203         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 204         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 205         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 206         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 207         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 208         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 209         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 210
 211         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 212         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 213         memcpy(&s->s_uuid, str->sb_uuid, 16);
 214 }
 215
 216 /**
 217  * gfs2_read_super - Read the gfs2 super block from disk
 218  * @sdp: The GFS2 super block
 219  * @sector: The location of the super block
 220  * @error: The error code to return
 221  *
 222  * This uses the bio functions to read the super block from disk
 223  * because we want to be 100% sure that we never read cached data.
 224  * A super block is read twice only during each GFS2 mount and is
 225  * never written to by the filesystem. The first time its read no
 226  * locks are held, and the only details which are looked at are those
 227  * relating to the locking protocol. Once locking is up and working,
 228  * the sb is read again under the lock to establish the location of
 229  * the master directory (contains pointers to journals etc) and the
 230  * root directory.
 231  *
 232  * Returns: 0 on success or error
 233  */
 234
 235 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
 236 {
 237         struct super_block *sb = sdp->sd_vfs;
 238         struct gfs2_sb *p;
 239         struct page *page;
 240         struct bio *bio;
 241
 242         page = alloc_page(GFP_NOFS);
 243         if (unlikely(!page))
 244                 return -ENOMEM;
 245
 246         ClearPageUptodate(page);
 247         ClearPageDirty(page);
 248         lock_page(page);
 249
 250         bio = bio_alloc(GFP_NOFS, 1);
 251         bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
 252         bio_set_dev(bio, sb->s_bdev);
 253         bio_add_page(bio, page, PAGE_SIZE, 0);
 254
 255         bio->bi_end_io = end_bio_io_page;
 256         bio->bi_private = page;
 257         bio_set_op_attrs(bio, REQ_OP_READ, REQ_META);
 258         submit_bio(bio);
 259         wait_on_page_locked(page);
 260         bio_put(bio);
 261         if (!PageUptodate(page)) {
 262                 __free_page(page);
 263                 return -EIO;
 264         }
 265         p = kmap(page);
 266         gfs2_sb_in(sdp, p);
 267         kunmap(page);
 268         __free_page(page);
 269         return gfs2_check_sb(sdp, silent);
 270 }
 271
 272 /**
 273  * gfs2_read_sb - Read super block
 274  * @sdp: The GFS2 superblock
 275  * @silent: Don't print message if mount fails
 276  *
 277  */
 278
 279 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
 280 {
 281         u32 hash_blocks, ind_blocks, leaf_blocks;
 282         u32 tmp_blocks;
 283         unsigned int x;
 284         int error;
 285
 286         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 287         if (error) {
 288                 if (!silent)
 289                         fs_err(sdp, "can't read superblock\n");
 290                 return error;
 291         }
 292
 293         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 294                                GFS2_BASIC_BLOCK_SHIFT;
 295         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
 296         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 297                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 298         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 299                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 300         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 301         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 302         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 303         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 304         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 305                                 sizeof(struct gfs2_meta_header)) /
 306                                 sizeof(struct gfs2_quota_change);
 307         sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
 308                                      sizeof(struct gfs2_meta_header))
 309                 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
 310
 311         /* Compute maximum reservation required to add a entry to a directory */
 312
 313         hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
 314                              sdp->sd_jbsize);
 315
 316         ind_blocks = 0;
 317         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 318                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 319                 ind_blocks += tmp_blocks;
 320         }
 321
 322         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 323
 324         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 325
 326         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 327                                 sizeof(struct gfs2_dinode);
 328         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 329         for (x = 2;; x++) {
 330                 u64 space, d;
 331                 u32 m;
 332
 333                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 334                 d = space;
 335                 m = do_div(d, sdp->sd_inptrs);
 336
 337                 if (d != sdp->sd_heightsize[x - 1] || m)
 338                         break;
 339                 sdp->sd_heightsize[x] = space;
 340         }
 341         sdp->sd_max_height = x;
 342         sdp->sd_heightsize[x] = ~0;
 343         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 344
 345         sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
 346                                  sizeof(struct gfs2_dinode);
 347         sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
 348         for (x = 2;; x++) {
 349                 u64 space, d;
 350                 u32 m;
 351
 352                 space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
 353                 d = space;
 354                 m = do_div(d, sdp->sd_inptrs);
 355
 356                 if (d != sdp->sd_jheightsize[x - 1] || m)
 357                         break;
 358                 sdp->sd_jheightsize[x] = space;
 359         }
 360         sdp->sd_max_jheight = x;
 361         sdp->sd_jheightsize[x] = ~0;
 362         gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
 363
 364         sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
 365                                       sizeof(struct gfs2_leaf)) /
 366                                      GFS2_MIN_DIRENT_SIZE;
 367         return 0;
 368 }
 369
 370 static int init_names(struct gfs2_sbd *sdp, int silent)
 371 {
 372         char *proto, *table;
 373         int error = 0;
 374
 375         proto = sdp->sd_args.ar_lockproto;
 376         table = sdp->sd_args.ar_locktable;
 377
 378         /*  Try to autodetect  */
 379
 380         if (!proto[0] || !table[0]) {
 381                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 382                 if (error)
 383                         return error;
 384
 385                 if (!proto[0])
 386                         proto = sdp->sd_sb.sb_lockproto;
 387                 if (!table[0])
 388                         table = sdp->sd_sb.sb_locktable;
 389         }
 390
 391         if (!table[0])
 392                 table = sdp->sd_vfs->s_id;
 393
 394         BUILD_BUG_ON(GFS2_LOCKNAME_LEN > GFS2_FSNAME_LEN);
 395
 396         strscpy(sdp->sd_proto_name, proto, GFS2_LOCKNAME_LEN);
 397         strscpy(sdp->sd_table_name, table, GFS2_LOCKNAME_LEN);
 398
 399         table = sdp->sd_table_name;
 400         while ((table = strchr(table, '/')))
 401                 *table = '_';
 402
 403         return error;
 404 }
 405
 406 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
 407                         int undo)
 408 {
 409         int error = 0;
 410
 411         if (undo)
 412                 goto fail_trans;
 413
 414         error = gfs2_glock_nq_num(sdp,
 415                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
 416                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
 417                                   mount_gh);
 418         if (error) {
 419                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
 420                 goto fail;
 421         }
 422
 423         error = gfs2_glock_nq_num(sdp,
 424                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
 425                                   LM_ST_SHARED,
 426                                   LM_FLAG_NOEXP | GL_EXACT,
 427                                   &sdp->sd_live_gh);
 428         if (error) {
 429                 fs_err(sdp, "can't acquire live glock: %d\n", error);
 430                 goto fail_mount;
 431         }
 432
 433         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
 434                                CREATE, &sdp->sd_rename_gl);
 435         if (error) {
 436                 fs_err(sdp, "can't create rename glock: %d\n", error);
 437                 goto fail_live;
 438         }
 439
 440         error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
 441                                CREATE, &sdp->sd_freeze_gl);
 442         if (error) {
 443                 fs_err(sdp, "can't create transaction glock: %d\n", error);
 444                 goto fail_rename;
 445         }
 446
 447         return 0;
 448
 449 fail_trans:
 450         gfs2_glock_put(sdp->sd_freeze_gl);
 451 fail_rename:
 452         gfs2_glock_put(sdp->sd_rename_gl);
 453 fail_live:
 454         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 455 fail_mount:
 456         gfs2_glock_dq_uninit(mount_gh);
 457 fail:
 458         return error;
 459 }
 460
 461 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
 462                             u64 no_addr, const char *name)
 463 {
 464         struct gfs2_sbd *sdp = sb->s_fs_info;
 465         struct dentry *dentry;
 466         struct inode *inode;
 467
 468         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
 469                                   GFS2_BLKST_FREE /* ignore */);
 470         if (IS_ERR(inode)) {
 471                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
 472                 return PTR_ERR(inode);
 473         }
 474         dentry = d_make_root(inode);
 475         if (!dentry) {
 476                 fs_err(sdp, "can't alloc %s dentry\n", name);
 477                 return -ENOMEM;
 478         }
 479         *dptr = dentry;
 480         return 0;
 481 }
 482
 483 static int init_sb(struct gfs2_sbd *sdp, int silent)
 484 {
 485         struct super_block *sb = sdp->sd_vfs;
 486         struct gfs2_holder sb_gh;
 487         u64 no_addr;
 488         int ret;
 489
 490         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
 491                                 LM_ST_SHARED, 0, &sb_gh);
 492         if (ret) {
 493                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
 494                 return ret;
 495         }
 496
 497         ret = gfs2_read_sb(sdp, silent);
 498         if (ret) {
 499                 fs_err(sdp, "can't read superblock: %d\n", ret);
 500                 goto out;
 501         }
 502
 503         /* Set up the buffer cache and SB for real */
 504         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
 505                 ret = -EINVAL;
 506                 fs_err(sdp, "FS block size (%u) is too small for device "
 507                        "block size (%u)\n",
 508                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
 509                 goto out;
 510         }
 511         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
 512                 ret = -EINVAL;
 513                 fs_err(sdp, "FS block size (%u) is too big for machine "
 514                        "page size (%u)\n",
 515                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
 516                 goto out;
 517         }
 518         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
 519
 520         /* Get the root inode */
 521         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
 522         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
 523         if (ret)
 524                 goto out;
 525
 526         /* Get the master inode */
 527         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
 528         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
 529         if (ret) {
 530                 dput(sdp->sd_root_dir);
 531                 goto out;
 532         }
 533         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
 534 out:
 535         gfs2_glock_dq_uninit(&sb_gh);
 536         return ret;
 537 }
 538
 539 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
 540 {
 541         char *message = "FIRSTMOUNT=Done";
 542         char *envp[] = { message, NULL };
 543
 544         fs_info(sdp, "first mount done, others may mount\n");
 545
 546         if (sdp->sd_lockstruct.ls_ops->lm_first_done)
 547                 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
 548
 549         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 550 }
 551
 552 /**
 553  * gfs2_jindex_hold - Grab a lock on the jindex
 554  * @sdp: The GFS2 superblock
 555  * @ji_gh: the holder for the jindex glock
 556  *
 557  * Returns: errno
 558  */
 559
 560 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 561 {
 562         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 563         struct qstr name;
 564         char buf[20];
 565         struct gfs2_jdesc *jd;
 566         int error;
 567
 568         name.name = buf;
 569
 570         mutex_lock(&sdp->sd_jindex_mutex);
 571
 572         for (;;) {
 573                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 574                 if (error)
 575                         break;
 576
 577                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 578                 name.hash = gfs2_disk_hash(name.name, name.len);
 579
 580                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 581                 if (error == -ENOENT) {
 582                         error = 0;
 583                         break;
 584                 }
 585
 586                 gfs2_glock_dq_uninit(ji_gh);
 587
 588                 if (error)
 589                         break;
 590
 591                 error = -ENOMEM;
 592                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 593                 if (!jd)
 594                         break;
 595
 596                 INIT_LIST_HEAD(&jd->extent_list);
 597                 INIT_LIST_HEAD(&jd->jd_revoke_list);
 598
 599                 INIT_WORK(&jd->jd_work, gfs2_recover_func);
 600                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
 601                 if (!jd->jd_inode || IS_ERR(jd->jd_inode)) {
 602                         if (!jd->jd_inode)
 603                                 error = -ENOENT;
 604                         else
 605                                 error = PTR_ERR(jd->jd_inode);
 606                         kfree(jd);
 607                         break;
 608                 }
 609
 610                 spin_lock(&sdp->sd_jindex_spin);
 611                 jd->jd_jid = sdp->sd_journals++;
 612                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 613                 spin_unlock(&sdp->sd_jindex_spin);
 614         }
 615
 616         mutex_unlock(&sdp->sd_jindex_mutex);
 617
 618         return error;
 619 }
 620
 621 /**
 622  * check_journal_clean - Make sure a journal is clean for a spectator mount
 623  * @sdp: The GFS2 superblock
 624  * @jd: The journal descriptor
 625  *
 626  * Returns: 0 if the journal is clean or locked, else an error
 627  */
 628 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
 629 {
 630         int error;
 631         struct gfs2_holder j_gh;
 632         struct gfs2_log_header_host head;
 633         struct gfs2_inode *ip;
 634
 635         ip = GFS2_I(jd->jd_inode);
 636         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
 637                                    GL_EXACT | GL_NOCACHE, &j_gh);
 638         if (error) {
 639                 fs_err(sdp, "Error locking journal for spectator mount.\n");
 640                 return -EPERM;
 641         }
 642         error = gfs2_jdesc_check(jd);
 643         if (error) {
 644                 fs_err(sdp, "Error checking journal for spectator mount.\n");
 645                 goto out_unlock;
 646         }
 647         error = gfs2_find_jhead(jd, &head);
 648         if (error) {
 649                 fs_err(sdp, "Error parsing journal for spectator mount.\n");
 650                 goto out_unlock;
 651         }
 652         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 653                 error = -EPERM;
 654                 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
 655                        "must not be a spectator.\n", jd->jd_jid);
 656         }
 657
 658 out_unlock:
 659         gfs2_glock_dq_uninit(&j_gh);
 660         return error;
 661 }
 662
 663 static int init_journal(struct gfs2_sbd *sdp, int undo)
 664 {
 665         struct inode *master = d_inode(sdp->sd_master_dir);
 666         struct gfs2_holder ji_gh;
 667         struct gfs2_inode *ip;
 668         int jindex = 1;
 669         int error = 0;
 670
 671         if (undo) {
 672                 jindex = 0;
 673                 goto fail_jinode_gh;
 674         }
 675
 676         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
 677         if (IS_ERR(sdp->sd_jindex)) {
 678                 fs_err(sdp, "can't lookup journal index: %d\n", error);
 679                 return PTR_ERR(sdp->sd_jindex);
 680         }
 681
 682         /* Load in the journal index special file */
 683
 684         error = gfs2_jindex_hold(sdp, &ji_gh);
 685         if (error) {
 686                 fs_err(sdp, "can't read journal index: %d\n", error);
 687                 goto fail;
 688         }
 689
 690         error = -EUSERS;
 691         if (!gfs2_jindex_size(sdp)) {
 692                 fs_err(sdp, "no journals!\n");
 693                 goto fail_jindex;
 694         }
 695
 696         atomic_set(&sdp->sd_log_blks_needed, 0);
 697         if (sdp->sd_args.ar_spectator) {
 698                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
 699                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 700                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 701                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 702         } else {
 703                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
 704                         fs_err(sdp, "can't mount journal #%u\n",
 705                                sdp->sd_lockstruct.ls_jid);
 706                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
 707                                gfs2_jindex_size(sdp),
 708                                gfs2_jindex_size(sdp) - 1);
 709                         goto fail_jindex;
 710                 }
 711                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
 712
 713                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
 714                                           &gfs2_journal_glops,
 715                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
 716                                           &sdp->sd_journal_gh);
 717                 if (error) {
 718                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
 719                         goto fail_jindex;
 720                 }
 721
 722                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 723                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 724                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
 725                                            &sdp->sd_jinode_gh);
 726                 if (error) {
 727                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
 728                                error);
 729                         goto fail_journal_gh;
 730                 }
 731
 732                 error = gfs2_jdesc_check(sdp->sd_jdesc);
 733                 if (error) {
 734                         fs_err(sdp, "my journal (%u) is bad: %d\n",
 735                                sdp->sd_jdesc->jd_jid, error);
 736                         goto fail_jinode_gh;
 737                 }
 738                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 739                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 740                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 741
 742                 /* Map the extents for this journal's blocks */
 743                 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
 744         }
 745         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
 746
 747         if (sdp->sd_lockstruct.ls_first) {
 748                 unsigned int x;
 749                 for (x = 0; x < sdp->sd_journals; x++) {
 750                         struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
 751
 752                         if (sdp->sd_args.ar_spectator) {
 753                                 error = check_journal_clean(sdp, jd);
 754                                 if (error)
 755                                         goto fail_jinode_gh;
 756                                 continue;
 757                         }
 758                         error = gfs2_recover_journal(jd, true);
 759                         if (error) {
 760                                 fs_err(sdp, "error recovering journal %u: %d\n",
 761                                        x, error);
 762                                 goto fail_jinode_gh;
 763                         }
 764                 }
 765
 766                 gfs2_others_may_mount(sdp);
 767         } else if (!sdp->sd_args.ar_spectator) {
 768                 error = gfs2_recover_journal(sdp->sd_jdesc, true);
 769                 if (error) {
 770                         fs_err(sdp, "error recovering my journal: %d\n", error);
 771                         goto fail_jinode_gh;
 772                 }
 773         }
 774
 775         sdp->sd_log_idle = 1;
 776         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
 777         gfs2_glock_dq_uninit(&ji_gh);
 778         jindex = 0;
 779         INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
 780         return 0;
 781
 782 fail_jinode_gh:
 783         if (!sdp->sd_args.ar_spectator)
 784                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 785 fail_journal_gh:
 786         if (!sdp->sd_args.ar_spectator)
 787                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 788 fail_jindex:
 789         gfs2_jindex_free(sdp);
 790         if (jindex)
 791                 gfs2_glock_dq_uninit(&ji_gh);
 792 fail:
 793         iput(sdp->sd_jindex);
 794         return error;
 795 }
 796
 797 static struct lock_class_key gfs2_quota_imutex_key;
 798
 799 static int init_inodes(struct gfs2_sbd *sdp, int undo)
 800 {
 801         int error = 0;
 802         struct inode *master = d_inode(sdp->sd_master_dir);
 803
 804         if (undo)
 805                 goto fail_qinode;
 806
 807         error = init_journal(sdp, undo);
 808         complete_all(&sdp->sd_journal_ready);
 809         if (error)
 810                 goto fail;
 811
 812         /* Read in the master statfs inode */
 813         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
 814         if (IS_ERR(sdp->sd_statfs_inode)) {
 815                 error = PTR_ERR(sdp->sd_statfs_inode);
 816                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
 817                 goto fail_journal;
 818         }
 819
 820         /* Read in the resource index inode */
 821         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
 822         if (IS_ERR(sdp->sd_rindex)) {
 823                 error = PTR_ERR(sdp->sd_rindex);
 824                 fs_err(sdp, "can't get resource index inode: %d\n", error);
 825                 goto fail_statfs;
 826         }
 827         sdp->sd_rindex_uptodate = 0;
 828
 829         /* Read in the quota inode */
 830         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
 831         if (IS_ERR(sdp->sd_quota_inode)) {
 832                 error = PTR_ERR(sdp->sd_quota_inode);
 833                 fs_err(sdp, "can't get quota file inode: %d\n", error);
 834                 goto fail_rindex;
 835         }
 836         /*
 837          * i_mutex on quota files is special. Since this inode is hidden system
 838          * file, we are safe to define locking ourselves.
 839          */
 840         lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
 841                           &gfs2_quota_imutex_key);
 842
 843         error = gfs2_rindex_update(sdp);
 844         if (error)
 845                 goto fail_qinode;
 846
 847         return 0;
 848
 849 fail_qinode:
 850         iput(sdp->sd_quota_inode);
 851 fail_rindex:
 852         gfs2_clear_rgrpd(sdp);
 853         iput(sdp->sd_rindex);
 854 fail_statfs:
 855         iput(sdp->sd_statfs_inode);
 856 fail_journal:
 857         init_journal(sdp, UNDO);
 858 fail:
 859         return error;
 860 }
 861
 862 static int init_per_node(struct gfs2_sbd *sdp, int undo)
 863 {
 864         struct inode *pn = NULL;
 865         char buf[30];
 866         int error = 0;
 867         struct gfs2_inode *ip;
 868         struct inode *master = d_inode(sdp->sd_master_dir);
 869
 870         if (sdp->sd_args.ar_spectator)
 871                 return 0;
 872
 873         if (undo)
 874                 goto fail_qc_gh;
 875
 876         pn = gfs2_lookup_simple(master, "per_node");
 877         if (IS_ERR(pn)) {
 878                 error = PTR_ERR(pn);
 879                 fs_err(sdp, "can't find per_node directory: %d\n", error);
 880                 return error;
 881         }
 882
 883         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
 884         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
 885         if (IS_ERR(sdp->sd_sc_inode)) {
 886                 error = PTR_ERR(sdp->sd_sc_inode);
 887                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
 888                 goto fail;
 889         }
 890
 891         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
 892         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
 893         if (IS_ERR(sdp->sd_qc_inode)) {
 894                 error = PTR_ERR(sdp->sd_qc_inode);
 895                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
 896                 goto fail_ut_i;
 897         }
 898
 899         iput(pn);
 900         pn = NULL;
 901
 902         ip = GFS2_I(sdp->sd_sc_inode);
 903         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 904                                    &sdp->sd_sc_gh);
 905         if (error) {
 906                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
 907                 goto fail_qc_i;
 908         }
 909
 910         ip = GFS2_I(sdp->sd_qc_inode);
 911         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 912                                    &sdp->sd_qc_gh);
 913         if (error) {
 914                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
 915                 goto fail_ut_gh;
 916         }
 917
 918         return 0;
 919
 920 fail_qc_gh:
 921         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 922 fail_ut_gh:
 923         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 924 fail_qc_i:
 925         iput(sdp->sd_qc_inode);
 926 fail_ut_i:
 927         iput(sdp->sd_sc_inode);
 928 fail:
 929         iput(pn);
 930         return error;
 931 }
 932
 933 static const match_table_t nolock_tokens = {
 934         { Opt_jid, "jid=%d", },
 935         { Opt_err, NULL },
 936 };
 937
 938 static const struct lm_lockops nolock_ops = {
 939         .lm_proto_name = "lock_nolock",
 940         .lm_put_lock = gfs2_glock_free,
 941         .lm_tokens = &nolock_tokens,
 942 };
 943
 944 /**
 945  * gfs2_lm_mount - mount a locking protocol
 946  * @sdp: the filesystem
 947  * @args: mount arguments
 948  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
 949  *
 950  * Returns: errno
 951  */
 952
 953 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 954 {
 955         const struct lm_lockops *lm;
 956         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 957         struct gfs2_args *args = &sdp->sd_args;
 958         const char *proto = sdp->sd_proto_name;
 959         const char *table = sdp->sd_table_name;
 960         char *o, *options;
 961         int ret;
 962
 963         if (!strcmp("lock_nolock", proto)) {
 964                 lm = &nolock_ops;
 965                 sdp->sd_args.ar_localflocks = 1;
 966 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
 967         } else if (!strcmp("lock_dlm", proto)) {
 968                 lm = &gfs2_dlm_ops;
 969 #endif
 970         } else {
 971                 pr_info("can't find protocol %s\n", proto);
 972                 return -ENOENT;
 973         }
 974
 975         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
 976
 977         ls->ls_ops = lm;
 978         ls->ls_first = 1;
 979
 980         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
 981                 substring_t tmp[MAX_OPT_ARGS];
 982                 int token, option;
 983
 984                 if (!o || !*o)
 985                         continue;
 986
 987                 token = match_token(o, *lm->lm_tokens, tmp);
 988                 switch (token) {
 989                 case Opt_jid:
 990                         ret = match_int(&tmp[0], &option);
 991                         if (ret || option < 0)
 992                                 goto hostdata_error;
 993                         if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
 994                                 ls->ls_jid = option;
 995                         break;
 996                 case Opt_id:
 997                 case Opt_nodir:
 998                         /* Obsolete, but left for backward compat purposes */
 999                         break;
1000                 case Opt_first:
1001                         ret = match_int(&tmp[0], &option);
1002                         if (ret || (option != 0 && option != 1))
1003                                 goto hostdata_error;
1004                         ls->ls_first = option;
1005                         break;
1006                 case Opt_err:
1007                 default:
1008 hostdata_error:
1009                         fs_info(sdp, "unknown hostdata (%s)\n", o);
1010                         return -EINVAL;
1011                 }
1012         }
1013
1014         if (lm->lm_mount == NULL) {
1015                 fs_info(sdp, "Now mounting FS...\n");
1016                 complete_all(&sdp->sd_locking_init);
1017                 return 0;
1018         }
1019         ret = lm->lm_mount(sdp, table);
1020         if (ret == 0)
1021                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1022         complete_all(&sdp->sd_locking_init);
1023         return ret;
1024 }
1025
1026 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1027 {
1028         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1029         if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) &&
1030             lm->lm_unmount)
1031                 lm->lm_unmount(sdp);
1032 }
1033
1034 static int wait_on_journal(struct gfs2_sbd *sdp)
1035 {
1036         if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
1037                 return 0;
1038
1039         return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
1040                 ? -EINTR : 0;
1041 }
1042
1043 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1044 {
1045         struct super_block *sb = sdp->sd_vfs;
1046         char ro[20];
1047         char spectator[20];
1048         char *envp[] = { ro, spectator, NULL };
1049         sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
1050         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1051         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1052 }
1053
1054 /**
1055  * fill_super - Read in superblock
1056  * @sb: The VFS superblock
1057  * @data: Mount options
1058  * @silent: Don't complain if it's not a GFS2 filesystem
1059  *
1060  * Returns: errno
1061  */
1062
1063 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1064 {
1065         struct gfs2_sbd *sdp;
1066         struct gfs2_holder mount_gh;
1067         int error;
1068
1069         sdp = init_sbd(sb);
1070         if (!sdp) {
1071                 pr_warn("can't alloc struct gfs2_sbd\n");
1072                 return -ENOMEM;
1073         }
1074         sdp->sd_args = *args;
1075
1076         if (sdp->sd_args.ar_spectator) {
1077                 sb->s_flags |= MS_RDONLY;
1078                 set_bit(SDF_RORECOVERY, &sdp->sd_flags);
1079         }
1080         if (sdp->sd_args.ar_posix_acl)
1081                 sb->s_flags |= MS_POSIXACL;
1082         if (sdp->sd_args.ar_nobarrier)
1083                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1084
1085         sb->s_flags |= MS_NOSEC;
1086         sb->s_magic = GFS2_MAGIC;
1087         sb->s_op = &gfs2_super_ops;
1088         sb->s_d_op = &gfs2_dops;
1089         sb->s_export_op = &gfs2_export_ops;
1090         sb->s_xattr = gfs2_xattr_handlers;
1091         sb->s_qcop = &gfs2_quotactl_ops;
1092         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1093         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1094         sb->s_time_gran = 1;
1095         sb->s_maxbytes = MAX_LFS_FILESIZE;
1096
1097         /* Set up the buffer cache and fill in some fake block size values
1098            to allow us to read-in the on-disk superblock. */
1099         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1100         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1101         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1102                                GFS2_BASIC_BLOCK_SHIFT;
1103         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
1104
1105         sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
1106         sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1107         if (sdp->sd_args.ar_statfs_quantum) {
1108                 sdp->sd_tune.gt_statfs_slow = 0;
1109                 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1110         } else {
1111                 sdp->sd_tune.gt_statfs_slow = 1;
1112                 sdp->sd_tune.gt_statfs_quantum = 30;
1113         }
1114
1115         error = init_names(sdp, silent);
1116         if (error) {
1117                 /* In this case, we haven't initialized sysfs, so we have to
1118                    manually free the sdp. */
1119                 free_percpu(sdp->sd_lkstats);
1120                 kfree(sdp);
1121                 sb->s_fs_info = NULL;
1122                 return error;
1123         }
1124
1125         snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
1126
1127         error = gfs2_sys_fs_add(sdp);
1128         /*
1129          * If we hit an error here, gfs2_sys_fs_add will have called function
1130          * kobject_put which causes the sysfs usage count to go to zero, which
1131          * causes sysfs to call function gfs2_sbd_release, which frees sdp.
1132          * Subsequent error paths here will call gfs2_sys_fs_del, which also
1133          * kobject_put to free sdp.
1134          */
1135         if (error)
1136                 return error;
1137
1138         gfs2_create_debugfs_file(sdp);
1139
1140         error = gfs2_lm_mount(sdp, silent);
1141         if (error)
1142                 goto fail_debug;
1143
1144         error = init_locking(sdp, &mount_gh, DO);
1145         if (error)
1146                 goto fail_lm;
1147
1148         error = init_sb(sdp, silent);
1149         if (error)
1150                 goto fail_locking;
1151
1152         error = wait_on_journal(sdp);
1153         if (error)
1154                 goto fail_sb;
1155
1156         /*
1157          * If user space has failed to join the cluster or some similar
1158          * failure has occurred, then the journal id will contain a
1159          * negative (error) number. This will then be returned to the
1160          * caller (of the mount syscall). We do this even for spectator
1161          * mounts (which just write a jid of 0 to indicate "ok" even though
1162          * the jid is unused in the spectator case)
1163          */
1164         if (sdp->sd_lockstruct.ls_jid < 0) {
1165                 error = sdp->sd_lockstruct.ls_jid;
1166                 sdp->sd_lockstruct.ls_jid = 0;
1167                 goto fail_sb;
1168         }
1169
1170         if (sdp->sd_args.ar_spectator)
1171                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
1172                          sdp->sd_table_name);
1173         else
1174                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
1175                          sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
1176
1177         error = init_inodes(sdp, DO);
1178         if (error)
1179                 goto fail_sb;
1180
1181         error = init_per_node(sdp, DO);
1182         if (error)
1183                 goto fail_inodes;
1184
1185         error = gfs2_statfs_init(sdp);
1186         if (error) {
1187                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1188                 goto fail_per_node;
1189         }
1190
1191         if (sb_rdonly(sb)) {
1192                 struct gfs2_holder freeze_gh;
1193
1194                 error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED,
1195                                            GL_EXACT, &freeze_gh);
1196                 if (error) {
1197                         fs_err(sdp, "can't make FS RO: %d\n", error);
1198                         goto fail_per_node;
1199                 }
1200                 gfs2_glock_dq_uninit(&freeze_gh);
1201         } else {
1202                 error = gfs2_make_fs_rw(sdp);
1203                 if (error) {
1204                         fs_err(sdp, "can't make FS RW: %d\n", error);
1205                         goto fail_per_node;
1206                 }
1207         }
1208
1209         gfs2_glock_dq_uninit(&mount_gh);
1210         gfs2_online_uevent(sdp);
1211         return 0;
1212
1213 fail_per_node:
1214         init_per_node(sdp, UNDO);
1215 fail_inodes:
1216         init_inodes(sdp, UNDO);
1217 fail_sb:
1218         if (sdp->sd_root_dir)
1219                 dput(sdp->sd_root_dir);
1220         if (sdp->sd_master_dir)
1221                 dput(sdp->sd_master_dir);
1222         if (sb->s_root)
1223                 dput(sb->s_root);
1224         sb->s_root = NULL;
1225 fail_locking:
1226         init_locking(sdp, &mount_gh, UNDO);
1227 fail_lm:
1228         complete_all(&sdp->sd_journal_ready);
1229         gfs2_gl_hash_clear(sdp);
1230         gfs2_lm_unmount(sdp);
1231 fail_debug:
1232         gfs2_delete_debugfs_file(sdp);
1233         free_percpu(sdp->sd_lkstats);
1234         /* gfs2_sys_fs_del must be the last thing we do, since it causes
1235          * sysfs to call function gfs2_sbd_release, which frees sdp. */
1236         gfs2_sys_fs_del(sdp);
1237         sb->s_fs_info = NULL;
1238         return error;
1239 }
1240
1241 static int set_gfs2_super(struct super_block *s, void *data)
1242 {
1243         s->s_bdev = data;
1244         s->s_dev = s->s_bdev->bd_dev;
1245         s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
1246         return 0;
1247 }
1248
1249 static int test_gfs2_super(struct super_block *s, void *ptr)
1250 {
1251         struct block_device *bdev = ptr;
1252         return (bdev == s->s_bdev);
1253 }
1254
1255 /**
1256  * gfs2_mount - Get the GFS2 superblock
1257  * @fs_type: The GFS2 filesystem type
1258  * @flags: Mount flags
1259  * @dev_name: The name of the device
1260  * @data: The mount arguments
1261  *
1262  * Q. Why not use get_sb_bdev() ?
1263  * A. We need to select one of two root directories to mount, independent
1264  *    of whether this is the initial, or subsequent, mount of this sb
1265  *
1266  * Returns: 0 or -ve on error
1267  */
1268
1269 static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
1270                        const char *dev_name, void *data)
1271 {
1272         struct block_device *bdev;
1273         struct super_block *s;
1274         fmode_t mode = FMODE_READ | FMODE_EXCL;
1275         int error;
1276         struct gfs2_args args;
1277         struct gfs2_sbd *sdp;
1278
1279         if (!(flags & MS_RDONLY))
1280                 mode |= FMODE_WRITE;
1281
1282         bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1283         if (IS_ERR(bdev))
1284                 return ERR_CAST(bdev);
1285
1286         /*
1287          * once the super is inserted into the list by sget, s_umount
1288          * will protect the lockfs code from trying to start a snapshot
1289          * while we are mounting
1290          */
1291         mutex_lock(&bdev->bd_fsfreeze_mutex);
1292         if (bdev->bd_fsfreeze_count > 0) {
1293                 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1294                 error = -EBUSY;
1295                 goto error_bdev;
1296         }
1297         s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
1298         mutex_unlock(&bdev->bd_fsfreeze_mutex);
1299         error = PTR_ERR(s);
1300         if (IS_ERR(s))
1301                 goto error_bdev;
1302
1303         if (s->s_root) {
1304                 /*
1305                  * s_umount nests inside bd_mutex during
1306                  * __invalidate_device().  blkdev_put() acquires
1307                  * bd_mutex and can't be called under s_umount.  Drop
1308                  * s_umount temporarily.  This is safe as we're
1309                  * holding an active reference.
1310                  */
1311                 up_write(&s->s_umount);
1312                 blkdev_put(bdev, mode);
1313                 down_write(&s->s_umount);
1314         } else {
1315                 /* s_mode must be set before deactivate_locked_super calls */
1316                 s->s_mode = mode;
1317         }
1318
1319         memset(&args, 0, sizeof(args));
1320         args.ar_quota = GFS2_QUOTA_DEFAULT;
1321         args.ar_data = GFS2_DATA_DEFAULT;
1322         args.ar_commit = 30;
1323         args.ar_statfs_quantum = 30;
1324         args.ar_quota_quantum = 60;
1325         args.ar_errors = GFS2_ERRORS_DEFAULT;
1326
1327         error = gfs2_mount_args(&args, data);
1328         if (error) {
1329                 pr_warn("can't parse mount arguments\n");
1330                 goto error_super;
1331         }
1332
1333         if (s->s_root) {
1334                 error = -EBUSY;
1335                 if ((flags ^ s->s_flags) & MS_RDONLY)
1336                         goto error_super;
1337         } else {
1338                 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1339                 sb_set_blocksize(s, block_size(bdev));
1340                 error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0);
1341                 if (error)
1342                         goto error_super;
1343                 s->s_flags |= MS_ACTIVE;
1344                 bdev->bd_super = s;
1345         }
1346
1347         sdp = s->s_fs_info;
1348         if (args.ar_meta)
1349                 return dget(sdp->sd_master_dir);
1350         else
1351                 return dget(sdp->sd_root_dir);
1352
1353 error_super:
1354         deactivate_locked_super(s);
1355         return ERR_PTR(error);
1356 error_bdev:
1357         blkdev_put(bdev, mode);
1358         return ERR_PTR(error);
1359 }
1360
1361 static int set_meta_super(struct super_block *s, void *ptr)
1362 {
1363         return -EINVAL;
1364 }
1365
1366 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1367                         int flags, const char *dev_name, void *data)
1368 {
1369         struct super_block *s;
1370         struct gfs2_sbd *sdp;
1371         struct path path;
1372         int error;
1373
1374         if (!dev_name || !*dev_name)
1375                 return ERR_PTR(-EINVAL);
1376
1377         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1378         if (error) {
1379                 pr_warn("path_lookup on %s returned error %d\n",
1380                         dev_name, error);
1381                 return ERR_PTR(error);
1382         }
1383         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1384                  path.dentry->d_sb->s_bdev);
1385         path_put(&path);
1386         if (IS_ERR(s)) {
1387                 pr_warn("gfs2 mount does not exist\n");
1388                 return ERR_CAST(s);
1389         }
1390         if ((flags ^ s->s_flags) & MS_RDONLY) {
1391                 deactivate_locked_super(s);
1392                 return ERR_PTR(-EBUSY);
1393         }
1394         sdp = s->s_fs_info;
1395         return dget(sdp->sd_master_dir);
1396 }
1397
1398 static void gfs2_kill_sb(struct super_block *sb)
1399 {
1400         struct gfs2_sbd *sdp = sb->s_fs_info;
1401
1402         if (sdp == NULL) {
1403                 kill_block_super(sb);
1404                 return;
1405         }
1406
1407         gfs2_log_flush(sdp, NULL, SYNC_FLUSH);
1408         dput(sdp->sd_root_dir);
1409         dput(sdp->sd_master_dir);
1410         sdp->sd_root_dir = NULL;
1411         sdp->sd_master_dir = NULL;
1412         shrink_dcache_sb(sb);
1413         free_percpu(sdp->sd_lkstats);
1414         kill_block_super(sb);
1415 }
1416
1417 struct file_system_type gfs2_fs_type = {
1418         .name = "gfs2",
1419         .fs_flags = FS_REQUIRES_DEV,
1420         .mount = gfs2_mount,
1421         .kill_sb = gfs2_kill_sb,
1422         .owner = THIS_MODULE,
1423 };
1424 MODULE_ALIAS_FS("gfs2");
1425
1426 struct file_system_type gfs2meta_fs_type = {
1427         .name = "gfs2meta",
1428         .fs_flags = FS_REQUIRES_DEV,
1429         .mount = gfs2_mount_meta,
1430         .owner = THIS_MODULE,
1431 };
1432 MODULE_ALIAS_FS("gfs2meta");