fs/gfs2/ops_fstype.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9 #include <linux/sched.h>
  10 #include <linux/slab.h>
  11 #include <linux/spinlock.h>
  12 #include <linux/completion.h>
  13 #include <linux/buffer_head.h>
  14 #include <linux/blkdev.h>
  15 #include <linux/kthread.h>
  16 #include <linux/export.h>
  17 #include <linux/namei.h>
  18 #include <linux/mount.h>
  19 #include <linux/gfs2_ondisk.h>
  20 #include <linux/quotaops.h>
  21 #include <linux/lockdep.h>
  22 #include <linux/module.h>
  23 #include <linux/backing-dev.h>
  24
  25 #include "gfs2.h"
  26 #include "incore.h"
  27 #include "bmap.h"
  28 #include "glock.h"
  29 #include "glops.h"
  30 #include "inode.h"
  31 #include "recovery.h"
  32 #include "rgrp.h"
  33 #include "super.h"
  34 #include "sys.h"
  35 #include "util.h"
  36 #include "log.h"
  37 #include "quota.h"
  38 #include "dir.h"
  39 #include "meta_io.h"
  40 #include "trace_gfs2.h"
  41 #include "lops.h"
  42
  43 #define DO 0
  44 #define UNDO 1
  45
  46 /**
  47  * gfs2_tune_init - Fill a gfs2_tune structure with default values
  48  * @gt: tune
  49  *
  50  */
  51
  52 static void gfs2_tune_init(struct gfs2_tune *gt)
  53 {
  54         spin_lock_init(&gt->gt_spin);
  55
  56         gt->gt_quota_warn_period = 10;
  57         gt->gt_quota_scale_num = 1;
  58         gt->gt_quota_scale_den = 1;
  59         gt->gt_new_files_jdata = 0;
  60         gt->gt_max_readahead = BIT(18);
  61         gt->gt_complain_secs = 10;
  62 }
  63
  64 void free_sbd(struct gfs2_sbd *sdp)
  65 {
  66         if (sdp->sd_lkstats)
  67                 free_percpu(sdp->sd_lkstats);
  68         kfree(sdp);
  69 }
  70
  71 static struct gfs2_sbd *init_sbd(struct super_block *sb)
  72 {
  73         struct gfs2_sbd *sdp;
  74         struct address_space *mapping;
  75
  76         sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
  77         if (!sdp)
  78                 return NULL;
  79
  80         sdp->sd_vfs = sb;
  81         sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
  82         if (!sdp->sd_lkstats)
  83                 goto fail;
  84         sb->s_fs_info = sdp;
  85
  86         set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
  87         gfs2_tune_init(&sdp->sd_tune);
  88
  89         init_waitqueue_head(&sdp->sd_glock_wait);
  90         atomic_set(&sdp->sd_glock_disposal, 0);
  91         init_completion(&sdp->sd_locking_init);
  92         init_completion(&sdp->sd_wdack);
  93         spin_lock_init(&sdp->sd_statfs_spin);
  94
  95         spin_lock_init(&sdp->sd_rindex_spin);
  96         sdp->sd_rindex_tree.rb_node = NULL;
  97
  98         INIT_LIST_HEAD(&sdp->sd_jindex_list);
  99         spin_lock_init(&sdp->sd_jindex_spin);
 100         mutex_init(&sdp->sd_jindex_mutex);
 101         init_completion(&sdp->sd_journal_ready);
 102
 103         INIT_LIST_HEAD(&sdp->sd_quota_list);
 104         mutex_init(&sdp->sd_quota_mutex);
 105         mutex_init(&sdp->sd_quota_sync_mutex);
 106         init_waitqueue_head(&sdp->sd_quota_wait);
 107         INIT_LIST_HEAD(&sdp->sd_trunc_list);
 108         spin_lock_init(&sdp->sd_trunc_lock);
 109         spin_lock_init(&sdp->sd_bitmap_lock);
 110
 111         mapping = &sdp->sd_aspace;
 112
 113         address_space_init_once(mapping);
 114         mapping->a_ops = &gfs2_rgrp_aops;
 115         mapping->host = sb->s_bdev->bd_inode;
 116         mapping->flags = 0;
 117         mapping_set_gfp_mask(mapping, GFP_NOFS);
 118         mapping->private_data = NULL;
 119         mapping->writeback_index = 0;
 120
 121         spin_lock_init(&sdp->sd_log_lock);
 122         atomic_set(&sdp->sd_log_pinned, 0);
 123         INIT_LIST_HEAD(&sdp->sd_log_revokes);
 124         INIT_LIST_HEAD(&sdp->sd_log_ordered);
 125         spin_lock_init(&sdp->sd_ordered_lock);
 126
 127         init_waitqueue_head(&sdp->sd_log_waitq);
 128         init_waitqueue_head(&sdp->sd_logd_waitq);
 129         spin_lock_init(&sdp->sd_ail_lock);
 130         INIT_LIST_HEAD(&sdp->sd_ail1_list);
 131         INIT_LIST_HEAD(&sdp->sd_ail2_list);
 132
 133         init_rwsem(&sdp->sd_log_flush_lock);
 134         atomic_set(&sdp->sd_log_in_flight, 0);
 135         atomic_set(&sdp->sd_reserving_log, 0);
 136         init_waitqueue_head(&sdp->sd_reserving_log_wait);
 137         init_waitqueue_head(&sdp->sd_log_flush_wait);
 138         atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 139         mutex_init(&sdp->sd_freeze_mutex);
 140
 141         return sdp;
 142
 143 fail:
 144         free_sbd(sdp);
 145         return NULL;
 146 }
 147
 148 /**
 149  * gfs2_check_sb - Check superblock
 150  * @sdp: the filesystem
 151  * @sb: The superblock
 152  * @silent: Don't print a message if the check fails
 153  *
 154  * Checks the version code of the FS is one that we understand how to
 155  * read and that the sizes of the various on-disk structures have not
 156  * changed.
 157  */
 158
 159 static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
 160 {
 161         struct gfs2_sb_host *sb = &sdp->sd_sb;
 162
 163         if (sb->sb_magic != GFS2_MAGIC ||
 164             sb->sb_type != GFS2_METATYPE_SB) {
 165                 if (!silent)
 166                         pr_warn("not a GFS2 filesystem\n");
 167                 return -EINVAL;
 168         }
 169
 170         /*  If format numbers match exactly, we're done.  */
 171
 172         if (sb->sb_fs_format == GFS2_FORMAT_FS &&
 173             sb->sb_multihost_format == GFS2_FORMAT_MULTI)
 174                 return 0;
 175
 176         fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
 177
 178         return -EINVAL;
 179 }
 180
 181 static void end_bio_io_page(struct bio *bio)
 182 {
 183         struct page *page = bio->bi_private;
 184
 185         if (!bio->bi_status)
 186                 SetPageUptodate(page);
 187         else
 188                 pr_warn("error %d reading superblock\n", bio->bi_status);
 189         unlock_page(page);
 190 }
 191
 192 static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
 193 {
 194         struct gfs2_sb_host *sb = &sdp->sd_sb;
 195         struct super_block *s = sdp->sd_vfs;
 196         const struct gfs2_sb *str = buf;
 197
 198         sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
 199         sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
 200         sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
 201         sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
 202         sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
 203         sb->sb_bsize = be32_to_cpu(str->sb_bsize);
 204         sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
 205         sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
 206         sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
 207         sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
 208         sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
 209
 210         memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
 211         memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
 212         memcpy(&s->s_uuid, str->sb_uuid, 16);
 213 }
 214
 215 /**
 216  * gfs2_read_super - Read the gfs2 super block from disk
 217  * @sdp: The GFS2 super block
 218  * @sector: The location of the super block
 219  * @error: The error code to return
 220  *
 221  * This uses the bio functions to read the super block from disk
 222  * because we want to be 100% sure that we never read cached data.
 223  * A super block is read twice only during each GFS2 mount and is
 224  * never written to by the filesystem. The first time its read no
 225  * locks are held, and the only details which are looked at are those
 226  * relating to the locking protocol. Once locking is up and working,
 227  * the sb is read again under the lock to establish the location of
 228  * the master directory (contains pointers to journals etc) and the
 229  * root directory.
 230  *
 231  * Returns: 0 on success or error
 232  */
 233
 234 static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
 235 {
 236         struct super_block *sb = sdp->sd_vfs;
 237         struct gfs2_sb *p;
 238         struct page *page;
 239         struct bio *bio;
 240
 241         page = alloc_page(GFP_NOFS);
 242         if (unlikely(!page))
 243                 return -ENOMEM;
 244
 245         ClearPageUptodate(page);
 246         ClearPageDirty(page);
 247         lock_page(page);
 248
 249         bio = bio_alloc(GFP_NOFS, 1);
 250         bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
 251         bio_set_dev(bio, sb->s_bdev);
 252         bio_add_page(bio, page, PAGE_SIZE, 0);
 253
 254         bio->bi_end_io = end_bio_io_page;
 255         bio->bi_private = page;
 256         bio_set_op_attrs(bio, REQ_OP_READ, REQ_META);
 257         submit_bio(bio);
 258         wait_on_page_locked(page);
 259         bio_put(bio);
 260         if (!PageUptodate(page)) {
 261                 __free_page(page);
 262                 return -EIO;
 263         }
 264         p = kmap(page);
 265         gfs2_sb_in(sdp, p);
 266         kunmap(page);
 267         __free_page(page);
 268         return gfs2_check_sb(sdp, silent);
 269 }
 270
 271 /**
 272  * gfs2_read_sb - Read super block
 273  * @sdp: The GFS2 superblock
 274  * @silent: Don't print message if mount fails
 275  *
 276  */
 277
 278 static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
 279 {
 280         u32 hash_blocks, ind_blocks, leaf_blocks;
 281         u32 tmp_blocks;
 282         unsigned int x;
 283         int error;
 284
 285         error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 286         if (error) {
 287                 if (!silent)
 288                         fs_err(sdp, "can't read superblock\n");
 289                 return error;
 290         }
 291
 292         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
 293                                GFS2_BASIC_BLOCK_SHIFT;
 294         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
 295         sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
 296                           sizeof(struct gfs2_dinode)) / sizeof(u64);
 297         sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
 298                           sizeof(struct gfs2_meta_header)) / sizeof(u64);
 299         sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
 300         sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
 301         sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
 302         sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
 303         sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
 304                                 sizeof(struct gfs2_meta_header)) /
 305                                 sizeof(struct gfs2_quota_change);
 306         sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
 307                                      sizeof(struct gfs2_meta_header))
 308                 * GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
 309
 310         /* Compute maximum reservation required to add a entry to a directory */
 311
 312         hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
 313                              sdp->sd_jbsize);
 314
 315         ind_blocks = 0;
 316         for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
 317                 tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
 318                 ind_blocks += tmp_blocks;
 319         }
 320
 321         leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
 322
 323         sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
 324
 325         sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
 326                                 sizeof(struct gfs2_dinode);
 327         sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
 328         for (x = 2;; x++) {
 329                 u64 space, d;
 330                 u32 m;
 331
 332                 space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
 333                 d = space;
 334                 m = do_div(d, sdp->sd_inptrs);
 335
 336                 if (d != sdp->sd_heightsize[x - 1] || m)
 337                         break;
 338                 sdp->sd_heightsize[x] = space;
 339         }
 340         sdp->sd_max_height = x;
 341         sdp->sd_heightsize[x] = ~0;
 342         gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
 343
 344         sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
 345                                       sizeof(struct gfs2_leaf)) /
 346                                      GFS2_MIN_DIRENT_SIZE;
 347         return 0;
 348 }
 349
 350 static int init_names(struct gfs2_sbd *sdp, int silent)
 351 {
 352         char *proto, *table;
 353         int error = 0;
 354
 355         proto = sdp->sd_args.ar_lockproto;
 356         table = sdp->sd_args.ar_locktable;
 357
 358         /*  Try to autodetect  */
 359
 360         if (!proto[0] || !table[0]) {
 361                 error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
 362                 if (error)
 363                         return error;
 364
 365                 if (!proto[0])
 366                         proto = sdp->sd_sb.sb_lockproto;
 367                 if (!table[0])
 368                         table = sdp->sd_sb.sb_locktable;
 369         }
 370
 371         if (!table[0])
 372                 table = sdp->sd_vfs->s_id;
 373
 374         strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
 375         strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
 376
 377         table = sdp->sd_table_name;
 378         while ((table = strchr(table, '/')))
 379                 *table = '_';
 380
 381         return error;
 382 }
 383
 384 static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
 385                         int undo)
 386 {
 387         int error = 0;
 388
 389         if (undo)
 390                 goto fail_trans;
 391
 392         error = gfs2_glock_nq_num(sdp,
 393                                   GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
 394                                   LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
 395                                   mount_gh);
 396         if (error) {
 397                 fs_err(sdp, "can't acquire mount glock: %d\n", error);
 398                 goto fail;
 399         }
 400
 401         error = gfs2_glock_nq_num(sdp,
 402                                   GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
 403                                   LM_ST_SHARED,
 404                                   LM_FLAG_NOEXP | GL_EXACT,
 405                                   &sdp->sd_live_gh);
 406         if (error) {
 407                 fs_err(sdp, "can't acquire live glock: %d\n", error);
 408                 goto fail_mount;
 409         }
 410
 411         error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
 412                                CREATE, &sdp->sd_rename_gl);
 413         if (error) {
 414                 fs_err(sdp, "can't create rename glock: %d\n", error);
 415                 goto fail_live;
 416         }
 417
 418         error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
 419                                CREATE, &sdp->sd_freeze_gl);
 420         if (error) {
 421                 fs_err(sdp, "can't create transaction glock: %d\n", error);
 422                 goto fail_rename;
 423         }
 424
 425         return 0;
 426
 427 fail_trans:
 428         gfs2_glock_put(sdp->sd_freeze_gl);
 429 fail_rename:
 430         gfs2_glock_put(sdp->sd_rename_gl);
 431 fail_live:
 432         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 433 fail_mount:
 434         gfs2_glock_dq_uninit(mount_gh);
 435 fail:
 436         return error;
 437 }
 438
 439 static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
 440                             u64 no_addr, const char *name)
 441 {
 442         struct gfs2_sbd *sdp = sb->s_fs_info;
 443         struct dentry *dentry;
 444         struct inode *inode;
 445
 446         inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
 447                                   GFS2_BLKST_FREE /* ignore */);
 448         if (IS_ERR(inode)) {
 449                 fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
 450                 return PTR_ERR(inode);
 451         }
 452         dentry = d_make_root(inode);
 453         if (!dentry) {
 454                 fs_err(sdp, "can't alloc %s dentry\n", name);
 455                 return -ENOMEM;
 456         }
 457         *dptr = dentry;
 458         return 0;
 459 }
 460
 461 static int init_sb(struct gfs2_sbd *sdp, int silent)
 462 {
 463         struct super_block *sb = sdp->sd_vfs;
 464         struct gfs2_holder sb_gh;
 465         u64 no_addr;
 466         int ret;
 467
 468         ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
 469                                 LM_ST_SHARED, 0, &sb_gh);
 470         if (ret) {
 471                 fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
 472                 return ret;
 473         }
 474
 475         ret = gfs2_read_sb(sdp, silent);
 476         if (ret) {
 477                 fs_err(sdp, "can't read superblock: %d\n", ret);
 478                 goto out;
 479         }
 480
 481         /* Set up the buffer cache and SB for real */
 482         if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
 483                 ret = -EINVAL;
 484                 fs_err(sdp, "FS block size (%u) is too small for device "
 485                        "block size (%u)\n",
 486                        sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
 487                 goto out;
 488         }
 489         if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
 490                 ret = -EINVAL;
 491                 fs_err(sdp, "FS block size (%u) is too big for machine "
 492                        "page size (%u)\n",
 493                        sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
 494                 goto out;
 495         }
 496         sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
 497
 498         /* Get the root inode */
 499         no_addr = sdp->sd_sb.sb_root_dir.no_addr;
 500         ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
 501         if (ret)
 502                 goto out;
 503
 504         /* Get the master inode */
 505         no_addr = sdp->sd_sb.sb_master_dir.no_addr;
 506         ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
 507         if (ret) {
 508                 dput(sdp->sd_root_dir);
 509                 goto out;
 510         }
 511         sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
 512 out:
 513         gfs2_glock_dq_uninit(&sb_gh);
 514         return ret;
 515 }
 516
 517 static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
 518 {
 519         char *message = "FIRSTMOUNT=Done";
 520         char *envp[] = { message, NULL };
 521
 522         fs_info(sdp, "first mount done, others may mount\n");
 523
 524         if (sdp->sd_lockstruct.ls_ops->lm_first_done)
 525                 sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
 526
 527         kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
 528 }
 529
 530 /**
 531  * gfs2_jindex_hold - Grab a lock on the jindex
 532  * @sdp: The GFS2 superblock
 533  * @ji_gh: the holder for the jindex glock
 534  *
 535  * Returns: errno
 536  */
 537
 538 static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
 539 {
 540         struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
 541         struct qstr name;
 542         char buf[20];
 543         struct gfs2_jdesc *jd;
 544         int error;
 545
 546         name.name = buf;
 547
 548         mutex_lock(&sdp->sd_jindex_mutex);
 549
 550         for (;;) {
 551                 error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
 552                 if (error)
 553                         break;
 554
 555                 name.len = sprintf(buf, "journal%u", sdp->sd_journals);
 556                 name.hash = gfs2_disk_hash(name.name, name.len);
 557
 558                 error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
 559                 if (error == -ENOENT) {
 560                         error = 0;
 561                         break;
 562                 }
 563
 564                 gfs2_glock_dq_uninit(ji_gh);
 565
 566                 if (error)
 567                         break;
 568
 569                 error = -ENOMEM;
 570                 jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
 571                 if (!jd)
 572                         break;
 573
 574                 INIT_LIST_HEAD(&jd->extent_list);
 575                 INIT_LIST_HEAD(&jd->jd_revoke_list);
 576
 577                 INIT_WORK(&jd->jd_work, gfs2_recover_func);
 578                 jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
 579                 if (IS_ERR_OR_NULL(jd->jd_inode)) {
 580                         if (!jd->jd_inode)
 581                                 error = -ENOENT;
 582                         else
 583                                 error = PTR_ERR(jd->jd_inode);
 584                         kfree(jd);
 585                         break;
 586                 }
 587
 588                 spin_lock(&sdp->sd_jindex_spin);
 589                 jd->jd_jid = sdp->sd_journals++;
 590                 list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
 591                 spin_unlock(&sdp->sd_jindex_spin);
 592         }
 593
 594         mutex_unlock(&sdp->sd_jindex_mutex);
 595
 596         return error;
 597 }
 598
 599 /**
 600  * check_journal_clean - Make sure a journal is clean for a spectator mount
 601  * @sdp: The GFS2 superblock
 602  * @jd: The journal descriptor
 603  *
 604  * Returns: 0 if the journal is clean or locked, else an error
 605  */
 606 static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
 607 {
 608         int error;
 609         struct gfs2_holder j_gh;
 610         struct gfs2_log_header_host head;
 611         struct gfs2_inode *ip;
 612
 613         ip = GFS2_I(jd->jd_inode);
 614         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
 615                                    GL_EXACT | GL_NOCACHE, &j_gh);
 616         if (error) {
 617                 fs_err(sdp, "Error locking journal for spectator mount.\n");
 618                 return -EPERM;
 619         }
 620         error = gfs2_jdesc_check(jd);
 621         if (error) {
 622                 fs_err(sdp, "Error checking journal for spectator mount.\n");
 623                 goto out_unlock;
 624         }
 625         error = gfs2_find_jhead(jd, &head, false);
 626         if (error) {
 627                 fs_err(sdp, "Error parsing journal for spectator mount.\n");
 628                 goto out_unlock;
 629         }
 630         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 631                 error = -EPERM;
 632                 fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
 633                        "must not be a spectator.\n", jd->jd_jid);
 634         }
 635
 636 out_unlock:
 637         gfs2_glock_dq_uninit(&j_gh);
 638         return error;
 639 }
 640
 641 static int init_journal(struct gfs2_sbd *sdp, int undo)
 642 {
 643         struct inode *master = d_inode(sdp->sd_master_dir);
 644         struct gfs2_holder ji_gh;
 645         struct gfs2_inode *ip;
 646         int jindex = 1;
 647         int error = 0;
 648
 649         if (undo) {
 650                 jindex = 0;
 651                 goto fail_jinode_gh;
 652         }
 653
 654         sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
 655         if (IS_ERR(sdp->sd_jindex)) {
 656                 fs_err(sdp, "can't lookup journal index: %d\n", error);
 657                 return PTR_ERR(sdp->sd_jindex);
 658         }
 659
 660         /* Load in the journal index special file */
 661
 662         error = gfs2_jindex_hold(sdp, &ji_gh);
 663         if (error) {
 664                 fs_err(sdp, "can't read journal index: %d\n", error);
 665                 goto fail;
 666         }
 667
 668         error = -EUSERS;
 669         if (!gfs2_jindex_size(sdp)) {
 670                 fs_err(sdp, "no journals!\n");
 671                 goto fail_jindex;
 672         }
 673
 674         atomic_set(&sdp->sd_log_blks_needed, 0);
 675         if (sdp->sd_args.ar_spectator) {
 676                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
 677                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 678                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 679                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 680         } else {
 681                 if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
 682                         fs_err(sdp, "can't mount journal #%u\n",
 683                                sdp->sd_lockstruct.ls_jid);
 684                         fs_err(sdp, "there are only %u journals (0 - %u)\n",
 685                                gfs2_jindex_size(sdp),
 686                                gfs2_jindex_size(sdp) - 1);
 687                         goto fail_jindex;
 688                 }
 689                 sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
 690
 691                 error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
 692                                           &gfs2_journal_glops,
 693                                           LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
 694                                           &sdp->sd_journal_gh);
 695                 if (error) {
 696                         fs_err(sdp, "can't acquire journal glock: %d\n", error);
 697                         goto fail_jindex;
 698                 }
 699
 700                 ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 701                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
 702                                            LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
 703                                            &sdp->sd_jinode_gh);
 704                 if (error) {
 705                         fs_err(sdp, "can't acquire journal inode glock: %d\n",
 706                                error);
 707                         goto fail_journal_gh;
 708                 }
 709
 710                 error = gfs2_jdesc_check(sdp->sd_jdesc);
 711                 if (error) {
 712                         fs_err(sdp, "my journal (%u) is bad: %d\n",
 713                                sdp->sd_jdesc->jd_jid, error);
 714                         goto fail_jinode_gh;
 715                 }
 716                 atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
 717                 atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
 718                 atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
 719
 720                 /* Map the extents for this journal's blocks */
 721                 gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
 722         }
 723         trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
 724
 725         if (sdp->sd_lockstruct.ls_first) {
 726                 unsigned int x;
 727                 for (x = 0; x < sdp->sd_journals; x++) {
 728                         struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
 729
 730                         if (sdp->sd_args.ar_spectator) {
 731                                 error = check_journal_clean(sdp, jd);
 732                                 if (error)
 733                                         goto fail_jinode_gh;
 734                                 continue;
 735                         }
 736                         error = gfs2_recover_journal(jd, true);
 737                         if (error) {
 738                                 fs_err(sdp, "error recovering journal %u: %d\n",
 739                                        x, error);
 740                                 goto fail_jinode_gh;
 741                         }
 742                 }
 743
 744                 gfs2_others_may_mount(sdp);
 745         } else if (!sdp->sd_args.ar_spectator) {
 746                 error = gfs2_recover_journal(sdp->sd_jdesc, true);
 747                 if (error) {
 748                         fs_err(sdp, "error recovering my journal: %d\n", error);
 749                         goto fail_jinode_gh;
 750                 }
 751         }
 752
 753         sdp->sd_log_idle = 1;
 754         set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
 755         gfs2_glock_dq_uninit(&ji_gh);
 756         jindex = 0;
 757         INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
 758         return 0;
 759
 760 fail_jinode_gh:
 761         if (!sdp->sd_args.ar_spectator)
 762                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 763 fail_journal_gh:
 764         if (!sdp->sd_args.ar_spectator)
 765                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 766 fail_jindex:
 767         gfs2_jindex_free(sdp);
 768         if (jindex)
 769                 gfs2_glock_dq_uninit(&ji_gh);
 770 fail:
 771         iput(sdp->sd_jindex);
 772         return error;
 773 }
 774
 775 static struct lock_class_key gfs2_quota_imutex_key;
 776
 777 static int init_inodes(struct gfs2_sbd *sdp, int undo)
 778 {
 779         int error = 0;
 780         struct inode *master = d_inode(sdp->sd_master_dir);
 781
 782         if (undo)
 783                 goto fail_qinode;
 784
 785         error = init_journal(sdp, undo);
 786         complete_all(&sdp->sd_journal_ready);
 787         if (error)
 788                 goto fail;
 789
 790         /* Read in the master statfs inode */
 791         sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
 792         if (IS_ERR(sdp->sd_statfs_inode)) {
 793                 error = PTR_ERR(sdp->sd_statfs_inode);
 794                 fs_err(sdp, "can't read in statfs inode: %d\n", error);
 795                 goto fail_journal;
 796         }
 797
 798         /* Read in the resource index inode */
 799         sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
 800         if (IS_ERR(sdp->sd_rindex)) {
 801                 error = PTR_ERR(sdp->sd_rindex);
 802                 fs_err(sdp, "can't get resource index inode: %d\n", error);
 803                 goto fail_statfs;
 804         }
 805         sdp->sd_rindex_uptodate = 0;
 806
 807         /* Read in the quota inode */
 808         sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
 809         if (IS_ERR(sdp->sd_quota_inode)) {
 810                 error = PTR_ERR(sdp->sd_quota_inode);
 811                 fs_err(sdp, "can't get quota file inode: %d\n", error);
 812                 goto fail_rindex;
 813         }
 814         /*
 815          * i_rwsem on quota files is special. Since this inode is hidden system
 816          * file, we are safe to define locking ourselves.
 817          */
 818         lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
 819                           &gfs2_quota_imutex_key);
 820
 821         error = gfs2_rindex_update(sdp);
 822         if (error)
 823                 goto fail_qinode;
 824
 825         return 0;
 826
 827 fail_qinode:
 828         iput(sdp->sd_quota_inode);
 829 fail_rindex:
 830         gfs2_clear_rgrpd(sdp);
 831         iput(sdp->sd_rindex);
 832 fail_statfs:
 833         iput(sdp->sd_statfs_inode);
 834 fail_journal:
 835         init_journal(sdp, UNDO);
 836 fail:
 837         return error;
 838 }
 839
 840 static int init_per_node(struct gfs2_sbd *sdp, int undo)
 841 {
 842         struct inode *pn = NULL;
 843         char buf[30];
 844         int error = 0;
 845         struct gfs2_inode *ip;
 846         struct inode *master = d_inode(sdp->sd_master_dir);
 847
 848         if (sdp->sd_args.ar_spectator)
 849                 return 0;
 850
 851         if (undo)
 852                 goto fail_qc_gh;
 853
 854         pn = gfs2_lookup_simple(master, "per_node");
 855         if (IS_ERR(pn)) {
 856                 error = PTR_ERR(pn);
 857                 fs_err(sdp, "can't find per_node directory: %d\n", error);
 858                 return error;
 859         }
 860
 861         sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
 862         sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
 863         if (IS_ERR(sdp->sd_sc_inode)) {
 864                 error = PTR_ERR(sdp->sd_sc_inode);
 865                 fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
 866                 goto fail;
 867         }
 868
 869         sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
 870         sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
 871         if (IS_ERR(sdp->sd_qc_inode)) {
 872                 error = PTR_ERR(sdp->sd_qc_inode);
 873                 fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
 874                 goto fail_ut_i;
 875         }
 876
 877         iput(pn);
 878         pn = NULL;
 879
 880         ip = GFS2_I(sdp->sd_sc_inode);
 881         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 882                                    &sdp->sd_sc_gh);
 883         if (error) {
 884                 fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
 885                 goto fail_qc_i;
 886         }
 887
 888         ip = GFS2_I(sdp->sd_qc_inode);
 889         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
 890                                    &sdp->sd_qc_gh);
 891         if (error) {
 892                 fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
 893                 goto fail_ut_gh;
 894         }
 895
 896         return 0;
 897
 898 fail_qc_gh:
 899         gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 900 fail_ut_gh:
 901         gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 902 fail_qc_i:
 903         iput(sdp->sd_qc_inode);
 904 fail_ut_i:
 905         iput(sdp->sd_sc_inode);
 906 fail:
 907         iput(pn);
 908         return error;
 909 }
 910
 911 static const match_table_t nolock_tokens = {
 912         { Opt_jid, "jid=%d\n", },
 913         { Opt_err, NULL },
 914 };
 915
 916 static const struct lm_lockops nolock_ops = {
 917         .lm_proto_name = "lock_nolock",
 918         .lm_put_lock = gfs2_glock_free,
 919         .lm_tokens = &nolock_tokens,
 920 };
 921
 922 /**
 923  * gfs2_lm_mount - mount a locking protocol
 924  * @sdp: the filesystem
 925  * @args: mount arguments
 926  * @silent: if 1, don't complain if the FS isn't a GFS2 fs
 927  *
 928  * Returns: errno
 929  */
 930
 931 static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
 932 {
 933         const struct lm_lockops *lm;
 934         struct lm_lockstruct *ls = &sdp->sd_lockstruct;
 935         struct gfs2_args *args = &sdp->sd_args;
 936         const char *proto = sdp->sd_proto_name;
 937         const char *table = sdp->sd_table_name;
 938         char *o, *options;
 939         int ret;
 940
 941         if (!strcmp("lock_nolock", proto)) {
 942                 lm = &nolock_ops;
 943                 sdp->sd_args.ar_localflocks = 1;
 944 #ifdef CONFIG_GFS2_FS_LOCKING_DLM
 945         } else if (!strcmp("lock_dlm", proto)) {
 946                 lm = &gfs2_dlm_ops;
 947 #endif
 948         } else {
 949                 pr_info("can't find protocol %s\n", proto);
 950                 return -ENOENT;
 951         }
 952
 953         fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
 954
 955         ls->ls_ops = lm;
 956         ls->ls_first = 1;
 957
 958         for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
 959                 substring_t tmp[MAX_OPT_ARGS];
 960                 int token, option;
 961
 962                 if (!o || !*o)
 963                         continue;
 964
 965                 token = match_token(o, *lm->lm_tokens, tmp);
 966                 switch (token) {
 967                 case Opt_jid:
 968                         ret = match_int(&tmp[0], &option);
 969                         if (ret || option < 0)
 970                                 goto hostdata_error;
 971                         if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
 972                                 ls->ls_jid = option;
 973                         break;
 974                 case Opt_id:
 975                 case Opt_nodir:
 976                         /* Obsolete, but left for backward compat purposes */
 977                         break;
 978                 case Opt_first:
 979                         ret = match_int(&tmp[0], &option);
 980                         if (ret || (option != 0 && option != 1))
 981                                 goto hostdata_error;
 982                         ls->ls_first = option;
 983                         break;
 984                 case Opt_err:
 985                 default:
 986 hostdata_error:
 987                         fs_info(sdp, "unknown hostdata (%s)\n", o);
 988                         return -EINVAL;
 989                 }
 990         }
 991
 992         if (lm->lm_mount == NULL) {
 993                 fs_info(sdp, "Now mounting FS...\n");
 994                 complete_all(&sdp->sd_locking_init);
 995                 return 0;
 996         }
 997         ret = lm->lm_mount(sdp, table);
 998         if (ret == 0)
 999                 fs_info(sdp, "Joined cluster. Now mounting FS...\n");
1000         complete_all(&sdp->sd_locking_init);
1001         return ret;
1002 }
1003
1004 void gfs2_lm_unmount(struct gfs2_sbd *sdp)
1005 {
1006         const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
1007         if (likely(!test_bit(SDF_WITHDRAWN, &sdp->sd_flags)) &&
1008             lm->lm_unmount)
1009                 lm->lm_unmount(sdp);
1010 }
1011
1012 static int wait_on_journal(struct gfs2_sbd *sdp)
1013 {
1014         if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
1015                 return 0;
1016
1017         return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
1018                 ? -EINTR : 0;
1019 }
1020
1021 void gfs2_online_uevent(struct gfs2_sbd *sdp)
1022 {
1023         struct super_block *sb = sdp->sd_vfs;
1024         char ro[20];
1025         char spectator[20];
1026         char *envp[] = { ro, spectator, NULL };
1027         sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
1028         sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
1029         kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
1030 }
1031
1032 /**
1033  * fill_super - Read in superblock
1034  * @sb: The VFS superblock
1035  * @data: Mount options
1036  * @silent: Don't complain if it's not a GFS2 filesystem
1037  *
1038  * Returns: errno
1039  */
1040
1041 static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
1042 {
1043         struct gfs2_sbd *sdp;
1044         struct gfs2_holder mount_gh;
1045         int error;
1046
1047         sdp = init_sbd(sb);
1048         if (!sdp) {
1049                 pr_warn("can't alloc struct gfs2_sbd\n");
1050                 return -ENOMEM;
1051         }
1052         sdp->sd_args = *args;
1053
1054         if (sdp->sd_args.ar_spectator) {
1055                 sb->s_flags |= SB_RDONLY;
1056                 set_bit(SDF_RORECOVERY, &sdp->sd_flags);
1057         }
1058         if (sdp->sd_args.ar_posix_acl)
1059                 sb->s_flags |= SB_POSIXACL;
1060         if (sdp->sd_args.ar_nobarrier)
1061                 set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
1062
1063         sb->s_flags |= SB_NOSEC;
1064         sb->s_magic = GFS2_MAGIC;
1065         sb->s_op = &gfs2_super_ops;
1066         sb->s_d_op = &gfs2_dops;
1067         sb->s_export_op = &gfs2_export_ops;
1068         sb->s_xattr = gfs2_xattr_handlers;
1069         sb->s_qcop = &gfs2_quotactl_ops;
1070         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
1071         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
1072         sb->s_time_gran = 1;
1073         sb->s_maxbytes = MAX_LFS_FILESIZE;
1074
1075         /* Set up the buffer cache and fill in some fake block size values
1076            to allow us to read-in the on-disk superblock. */
1077         sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
1078         sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
1079         sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
1080                                GFS2_BASIC_BLOCK_SHIFT;
1081         sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
1082
1083         sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
1084         sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
1085         if (sdp->sd_args.ar_statfs_quantum) {
1086                 sdp->sd_tune.gt_statfs_slow = 0;
1087                 sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
1088         } else {
1089                 sdp->sd_tune.gt_statfs_slow = 1;
1090                 sdp->sd_tune.gt_statfs_quantum = 30;
1091         }
1092
1093         error = init_names(sdp, silent);
1094         if (error) {
1095                 /* In this case, we haven't initialized sysfs, so we have to
1096                    manually free the sdp. */
1097                 free_sbd(sdp);
1098                 sb->s_fs_info = NULL;
1099                 return error;
1100         }
1101
1102         snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
1103
1104         error = gfs2_sys_fs_add(sdp);
1105         /*
1106          * If we hit an error here, gfs2_sys_fs_add will have called function
1107          * kobject_put which causes the sysfs usage count to go to zero, which
1108          * causes sysfs to call function gfs2_sbd_release, which frees sdp.
1109          * Subsequent error paths here will call gfs2_sys_fs_del, which also
1110          * kobject_put to free sdp.
1111          */
1112         if (error)
1113                 return error;
1114
1115         gfs2_create_debugfs_file(sdp);
1116
1117         error = gfs2_lm_mount(sdp, silent);
1118         if (error)
1119                 goto fail_debug;
1120
1121         error = init_locking(sdp, &mount_gh, DO);
1122         if (error)
1123                 goto fail_lm;
1124
1125         error = init_sb(sdp, silent);
1126         if (error)
1127                 goto fail_locking;
1128
1129         error = wait_on_journal(sdp);
1130         if (error)
1131                 goto fail_sb;
1132
1133         /*
1134          * If user space has failed to join the cluster or some similar
1135          * failure has occurred, then the journal id will contain a
1136          * negative (error) number. This will then be returned to the
1137          * caller (of the mount syscall). We do this even for spectator
1138          * mounts (which just write a jid of 0 to indicate "ok" even though
1139          * the jid is unused in the spectator case)
1140          */
1141         if (sdp->sd_lockstruct.ls_jid < 0) {
1142                 error = sdp->sd_lockstruct.ls_jid;
1143                 sdp->sd_lockstruct.ls_jid = 0;
1144                 goto fail_sb;
1145         }
1146
1147         if (sdp->sd_args.ar_spectator)
1148                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
1149                          sdp->sd_table_name);
1150         else
1151                 snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
1152                          sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
1153
1154         error = init_inodes(sdp, DO);
1155         if (error)
1156                 goto fail_sb;
1157
1158         error = init_per_node(sdp, DO);
1159         if (error)
1160                 goto fail_inodes;
1161
1162         error = gfs2_statfs_init(sdp);
1163         if (error) {
1164                 fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
1165                 goto fail_per_node;
1166         }
1167
1168         if (!sb_rdonly(sb)) {
1169                 error = gfs2_make_fs_rw(sdp);
1170                 if (error) {
1171                         fs_err(sdp, "can't make FS RW: %d\n", error);
1172                         goto fail_per_node;
1173                 }
1174         }
1175
1176         gfs2_glock_dq_uninit(&mount_gh);
1177         gfs2_online_uevent(sdp);
1178         return 0;
1179
1180 fail_per_node:
1181         init_per_node(sdp, UNDO);
1182 fail_inodes:
1183         init_inodes(sdp, UNDO);
1184 fail_sb:
1185         if (sdp->sd_root_dir)
1186                 dput(sdp->sd_root_dir);
1187         if (sdp->sd_master_dir)
1188                 dput(sdp->sd_master_dir);
1189         if (sb->s_root)
1190                 dput(sb->s_root);
1191         sb->s_root = NULL;
1192 fail_locking:
1193         init_locking(sdp, &mount_gh, UNDO);
1194 fail_lm:
1195         complete_all(&sdp->sd_journal_ready);
1196         gfs2_gl_hash_clear(sdp);
1197         gfs2_lm_unmount(sdp);
1198 fail_debug:
1199         gfs2_delete_debugfs_file(sdp);
1200         /* gfs2_sys_fs_del must be the last thing we do, since it causes
1201          * sysfs to call function gfs2_sbd_release, which frees sdp. */
1202         gfs2_sys_fs_del(sdp);
1203         sb->s_fs_info = NULL;
1204         return error;
1205 }
1206
1207 static int set_gfs2_super(struct super_block *s, void *data)
1208 {
1209         s->s_bdev = data;
1210         s->s_dev = s->s_bdev->bd_dev;
1211         s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
1212         return 0;
1213 }
1214
1215 static int test_gfs2_super(struct super_block *s, void *ptr)
1216 {
1217         struct block_device *bdev = ptr;
1218         return (bdev == s->s_bdev);
1219 }
1220
1221 /**
1222  * gfs2_mount - Get the GFS2 superblock
1223  * @fs_type: The GFS2 filesystem type
1224  * @flags: Mount flags
1225  * @dev_name: The name of the device
1226  * @data: The mount arguments
1227  *
1228  * Q. Why not use get_sb_bdev() ?
1229  * A. We need to select one of two root directories to mount, independent
1230  *    of whether this is the initial, or subsequent, mount of this sb
1231  *
1232  * Returns: 0 or -ve on error
1233  */
1234
1235 static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
1236                        const char *dev_name, void *data)
1237 {
1238         struct block_device *bdev;
1239         struct super_block *s;
1240         fmode_t mode = FMODE_READ | FMODE_EXCL;
1241         int error;
1242         struct gfs2_args args;
1243         struct gfs2_sbd *sdp;
1244
1245         if (!(flags & SB_RDONLY))
1246                 mode |= FMODE_WRITE;
1247
1248         bdev = blkdev_get_by_path(dev_name, mode, fs_type);
1249         if (IS_ERR(bdev))
1250                 return ERR_CAST(bdev);
1251
1252         /*
1253          * once the super is inserted into the list by sget, s_umount
1254          * will protect the lockfs code from trying to start a snapshot
1255          * while we are mounting
1256          */
1257         mutex_lock(&bdev->bd_fsfreeze_mutex);
1258         if (bdev->bd_fsfreeze_count > 0) {
1259                 mutex_unlock(&bdev->bd_fsfreeze_mutex);
1260                 error = -EBUSY;
1261                 goto error_bdev;
1262         }
1263         s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
1264         mutex_unlock(&bdev->bd_fsfreeze_mutex);
1265         error = PTR_ERR(s);
1266         if (IS_ERR(s))
1267                 goto error_bdev;
1268
1269         if (s->s_root) {
1270                 /*
1271                  * s_umount nests inside bd_mutex during
1272                  * __invalidate_device().  blkdev_put() acquires
1273                  * bd_mutex and can't be called under s_umount.  Drop
1274                  * s_umount temporarily.  This is safe as we're
1275                  * holding an active reference.
1276                  */
1277                 up_write(&s->s_umount);
1278                 blkdev_put(bdev, mode);
1279                 down_write(&s->s_umount);
1280         } else {
1281                 /* s_mode must be set before deactivate_locked_super calls */
1282                 s->s_mode = mode;
1283         }
1284
1285         memset(&args, 0, sizeof(args));
1286         args.ar_quota = GFS2_QUOTA_DEFAULT;
1287         args.ar_data = GFS2_DATA_DEFAULT;
1288         args.ar_commit = 30;
1289         args.ar_statfs_quantum = 30;
1290         args.ar_quota_quantum = 60;
1291         args.ar_errors = GFS2_ERRORS_DEFAULT;
1292
1293         error = gfs2_mount_args(&args, data);
1294         if (error) {
1295                 pr_warn("can't parse mount arguments\n");
1296                 goto error_super;
1297         }
1298
1299         if (s->s_root) {
1300                 error = -EBUSY;
1301                 if ((flags ^ s->s_flags) & SB_RDONLY)
1302                         goto error_super;
1303         } else {
1304                 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1305                 sb_set_blocksize(s, block_size(bdev));
1306                 error = fill_super(s, &args, flags & SB_SILENT ? 1 : 0);
1307                 if (error)
1308                         goto error_super;
1309                 s->s_flags |= SB_ACTIVE;
1310                 bdev->bd_super = s;
1311         }
1312
1313         sdp = s->s_fs_info;
1314         if (args.ar_meta)
1315                 return dget(sdp->sd_master_dir);
1316         else
1317                 return dget(sdp->sd_root_dir);
1318
1319 error_super:
1320         deactivate_locked_super(s);
1321         return ERR_PTR(error);
1322 error_bdev:
1323         blkdev_put(bdev, mode);
1324         return ERR_PTR(error);
1325 }
1326
1327 static int set_meta_super(struct super_block *s, void *ptr)
1328 {
1329         return -EINVAL;
1330 }
1331
1332 static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
1333                         int flags, const char *dev_name, void *data)
1334 {
1335         struct super_block *s;
1336         struct gfs2_sbd *sdp;
1337         struct path path;
1338         int error;
1339
1340         if (!dev_name || !*dev_name)
1341                 return ERR_PTR(-EINVAL);
1342
1343         error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
1344         if (error) {
1345                 pr_warn("path_lookup on %s returned error %d\n",
1346                         dev_name, error);
1347                 return ERR_PTR(error);
1348         }
1349         s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
1350                  path.dentry->d_sb->s_bdev);
1351         path_put(&path);
1352         if (IS_ERR(s)) {
1353                 pr_warn("gfs2 mount does not exist\n");
1354                 return ERR_CAST(s);
1355         }
1356         if ((flags ^ s->s_flags) & SB_RDONLY) {
1357                 deactivate_locked_super(s);
1358                 return ERR_PTR(-EBUSY);
1359         }
1360         sdp = s->s_fs_info;
1361         return dget(sdp->sd_master_dir);
1362 }
1363
1364 static void gfs2_kill_sb(struct super_block *sb)
1365 {
1366         struct gfs2_sbd *sdp = sb->s_fs_info;
1367
1368         if (sdp == NULL) {
1369                 kill_block_super(sb);
1370                 return;
1371         }
1372
1373         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SYNC | GFS2_LFC_KILL_SB);
1374         dput(sdp->sd_root_dir);
1375         dput(sdp->sd_master_dir);
1376         sdp->sd_root_dir = NULL;
1377         sdp->sd_master_dir = NULL;
1378         shrink_dcache_sb(sb);
1379         kill_block_super(sb);
1380 }
1381
1382 struct file_system_type gfs2_fs_type = {
1383         .name = "gfs2",
1384         .fs_flags = FS_REQUIRES_DEV,
1385         .mount = gfs2_mount,
1386         .kill_sb = gfs2_kill_sb,
1387         .owner = THIS_MODULE,
1388 };
1389 MODULE_ALIAS_FS("gfs2");
1390
1391 struct file_system_type gfs2meta_fs_type = {
1392         .name = "gfs2meta",
1393         .fs_flags = FS_REQUIRES_DEV,
1394         .mount = gfs2_mount_meta,
1395         .owner = THIS_MODULE,
1396 };
1397 MODULE_ALIAS_FS("gfs2meta");