fs/gfs2/super.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   4  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
   5  */
   6
   7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   8
   9 #include <linux/bio.h>
  10 #include <linux/sched/signal.h>
  11 #include <linux/slab.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/completion.h>
  14 #include <linux/buffer_head.h>
  15 #include <linux/statfs.h>
  16 #include <linux/seq_file.h>
  17 #include <linux/mount.h>
  18 #include <linux/kthread.h>
  19 #include <linux/delay.h>
  20 #include <linux/gfs2_ondisk.h>
  21 #include <linux/crc32.h>
  22 #include <linux/time.h>
  23 #include <linux/wait.h>
  24 #include <linux/writeback.h>
  25 #include <linux/backing-dev.h>
  26 #include <linux/kernel.h>
  27
  28 #include "gfs2.h"
  29 #include "incore.h"
  30 #include "bmap.h"
  31 #include "dir.h"
  32 #include "glock.h"
  33 #include "glops.h"
  34 #include "inode.h"
  35 #include "log.h"
  36 #include "meta_io.h"
  37 #include "quota.h"
  38 #include "recovery.h"
  39 #include "rgrp.h"
  40 #include "super.h"
  41 #include "trans.h"
  42 #include "util.h"
  43 #include "sys.h"
  44 #include "xattr.h"
  45 #include "lops.h"
  46
  47 enum dinode_demise {
  48         SHOULD_DELETE_DINODE,
  49         SHOULD_NOT_DELETE_DINODE,
  50         SHOULD_DEFER_EVICTION,
  51 };
  52
  53 /**
  54  * gfs2_jindex_free - Clear all the journal index information
  55  * @sdp: The GFS2 superblock
  56  *
  57  */
  58
  59 void gfs2_jindex_free(struct gfs2_sbd *sdp)
  60 {
  61         struct list_head list;
  62         struct gfs2_jdesc *jd;
  63
  64         spin_lock(&sdp->sd_jindex_spin);
  65         list_add(&list, &sdp->sd_jindex_list);
  66         list_del_init(&sdp->sd_jindex_list);
  67         sdp->sd_journals = 0;
  68         spin_unlock(&sdp->sd_jindex_spin);
  69
  70         sdp->sd_jdesc = NULL;
  71         while (!list_empty(&list)) {
  72                 jd = list_first_entry(&list, struct gfs2_jdesc, jd_list);
  73                 gfs2_free_journal_extents(jd);
  74                 list_del(&jd->jd_list);
  75                 iput(jd->jd_inode);
  76                 jd->jd_inode = NULL;
  77                 kfree(jd);
  78         }
  79 }
  80
  81 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
  82 {
  83         struct gfs2_jdesc *jd;
  84
  85         list_for_each_entry(jd, head, jd_list) {
  86                 if (jd->jd_jid == jid)
  87                         return jd;
  88         }
  89         return NULL;
  90 }
  91
  92 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
  93 {
  94         struct gfs2_jdesc *jd;
  95
  96         spin_lock(&sdp->sd_jindex_spin);
  97         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
  98         spin_unlock(&sdp->sd_jindex_spin);
  99
 100         return jd;
 101 }
 102
 103 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 104 {
 105         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 106         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 107         u64 size = i_size_read(jd->jd_inode);
 108
 109         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, BIT(30)))
 110                 return -EIO;
 111
 112         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
 113
 114         if (gfs2_write_alloc_required(ip, 0, size)) {
 115                 gfs2_consist_inode(ip);
 116                 return -EIO;
 117         }
 118
 119         return 0;
 120 }
 121
 122 static int init_threads(struct gfs2_sbd *sdp)
 123 {
 124         struct task_struct *p;
 125         int error = 0;
 126
 127         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
 128         if (IS_ERR(p)) {
 129                 error = PTR_ERR(p);
 130                 fs_err(sdp, "can't start logd thread: %d\n", error);
 131                 return error;
 132         }
 133         sdp->sd_logd_process = p;
 134
 135         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
 136         if (IS_ERR(p)) {
 137                 error = PTR_ERR(p);
 138                 fs_err(sdp, "can't start quotad thread: %d\n", error);
 139                 goto fail;
 140         }
 141         sdp->sd_quotad_process = p;
 142         return 0;
 143
 144 fail:
 145         kthread_stop(sdp->sd_logd_process);
 146         sdp->sd_logd_process = NULL;
 147         return error;
 148 }
 149
 150 /**
 151  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 152  * @sdp: the filesystem
 153  *
 154  * Returns: errno
 155  */
 156
 157 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 158 {
 159         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 160         struct gfs2_glock *j_gl = ip->i_gl;
 161         struct gfs2_log_header_host head;
 162         int error;
 163
 164         error = init_threads(sdp);
 165         if (error) {
 166                 gfs2_withdraw_delayed(sdp);
 167                 return error;
 168         }
 169
 170         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 171         if (gfs2_withdrawn(sdp)) {
 172                 error = -EIO;
 173                 goto fail;
 174         }
 175
 176         error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
 177         if (error || gfs2_withdrawn(sdp))
 178                 goto fail;
 179
 180         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 181                 gfs2_consist(sdp);
 182                 error = -EIO;
 183                 goto fail;
 184         }
 185
 186         /*  Initialize some head of the log stuff  */
 187         sdp->sd_log_sequence = head.lh_sequence + 1;
 188         gfs2_log_pointers_init(sdp, head.lh_blkno);
 189
 190         error = gfs2_quota_init(sdp);
 191         if (error || gfs2_withdrawn(sdp))
 192                 goto fail;
 193
 194         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 195
 196         return 0;
 197
 198 fail:
 199         if (sdp->sd_quotad_process)
 200                 kthread_stop(sdp->sd_quotad_process);
 201         sdp->sd_quotad_process = NULL;
 202         if (sdp->sd_logd_process)
 203                 kthread_stop(sdp->sd_logd_process);
 204         sdp->sd_logd_process = NULL;
 205         return error;
 206 }
 207
 208 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 209 {
 210         const struct gfs2_statfs_change *str = buf;
 211
 212         sc->sc_total = be64_to_cpu(str->sc_total);
 213         sc->sc_free = be64_to_cpu(str->sc_free);
 214         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 215 }
 216
 217 void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 218 {
 219         struct gfs2_statfs_change *str = buf;
 220
 221         str->sc_total = cpu_to_be64(sc->sc_total);
 222         str->sc_free = cpu_to_be64(sc->sc_free);
 223         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 224 }
 225
 226 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 227 {
 228         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 229         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 230         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 231         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 232         struct buffer_head *m_bh, *l_bh;
 233         struct gfs2_holder gh;
 234         int error;
 235
 236         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 237                                    &gh);
 238         if (error)
 239                 return error;
 240
 241         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 242         if (error)
 243                 goto out;
 244
 245         if (sdp->sd_args.ar_spectator) {
 246                 spin_lock(&sdp->sd_statfs_spin);
 247                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 248                                       sizeof(struct gfs2_dinode));
 249                 spin_unlock(&sdp->sd_statfs_spin);
 250         } else {
 251                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 252                 if (error)
 253                         goto out_m_bh;
 254
 255                 spin_lock(&sdp->sd_statfs_spin);
 256                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 257                                       sizeof(struct gfs2_dinode));
 258                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 259                                       sizeof(struct gfs2_dinode));
 260                 spin_unlock(&sdp->sd_statfs_spin);
 261
 262                 brelse(l_bh);
 263         }
 264
 265 out_m_bh:
 266         brelse(m_bh);
 267 out:
 268         gfs2_glock_dq_uninit(&gh);
 269         return 0;
 270 }
 271
 272 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 273                         s64 dinodes)
 274 {
 275         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 276         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 277         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 278         struct buffer_head *l_bh;
 279         s64 x, y;
 280         int need_sync = 0;
 281         int error;
 282
 283         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 284         if (error)
 285                 return;
 286
 287         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 288
 289         spin_lock(&sdp->sd_statfs_spin);
 290         l_sc->sc_total += total;
 291         l_sc->sc_free += free;
 292         l_sc->sc_dinodes += dinodes;
 293         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 294         if (sdp->sd_args.ar_statfs_percent) {
 295                 x = 100 * l_sc->sc_free;
 296                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 297                 if (x >= y || x <= -y)
 298                         need_sync = 1;
 299         }
 300         spin_unlock(&sdp->sd_statfs_spin);
 301
 302         brelse(l_bh);
 303         if (need_sync)
 304                 gfs2_wake_up_statfs(sdp);
 305 }
 306
 307 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 308                    struct buffer_head *l_bh)
 309 {
 310         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 311         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 312         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 313         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 314
 315         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 316         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
 317
 318         spin_lock(&sdp->sd_statfs_spin);
 319         m_sc->sc_total += l_sc->sc_total;
 320         m_sc->sc_free += l_sc->sc_free;
 321         m_sc->sc_dinodes += l_sc->sc_dinodes;
 322         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 323         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 324                0, sizeof(struct gfs2_statfs_change));
 325         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 326         spin_unlock(&sdp->sd_statfs_spin);
 327 }
 328
 329 int gfs2_statfs_sync(struct super_block *sb, int type)
 330 {
 331         struct gfs2_sbd *sdp = sb->s_fs_info;
 332         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 333         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 334         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 335         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 336         struct gfs2_holder gh;
 337         struct buffer_head *m_bh, *l_bh;
 338         int error;
 339
 340         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 341                                    &gh);
 342         if (error)
 343                 goto out;
 344
 345         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 346         if (error)
 347                 goto out_unlock;
 348
 349         spin_lock(&sdp->sd_statfs_spin);
 350         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 351                               sizeof(struct gfs2_dinode));
 352         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 353                 spin_unlock(&sdp->sd_statfs_spin);
 354                 goto out_bh;
 355         }
 356         spin_unlock(&sdp->sd_statfs_spin);
 357
 358         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 359         if (error)
 360                 goto out_bh;
 361
 362         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 363         if (error)
 364                 goto out_bh2;
 365
 366         update_statfs(sdp, m_bh, l_bh);
 367         sdp->sd_statfs_force_sync = 0;
 368
 369         gfs2_trans_end(sdp);
 370
 371 out_bh2:
 372         brelse(l_bh);
 373 out_bh:
 374         brelse(m_bh);
 375 out_unlock:
 376         gfs2_glock_dq_uninit(&gh);
 377 out:
 378         return error;
 379 }
 380
 381 struct lfcc {
 382         struct list_head list;
 383         struct gfs2_holder gh;
 384 };
 385
 386 /**
 387  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 388  *                            journals are clean
 389  * @sdp: the file system
 390  *
 391  * Returns: errno
 392  */
 393
 394 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
 395 {
 396         struct gfs2_inode *ip;
 397         struct gfs2_jdesc *jd;
 398         struct lfcc *lfcc;
 399         LIST_HEAD(list);
 400         struct gfs2_log_header_host lh;
 401         int error;
 402
 403         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 404                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 405                 if (!lfcc) {
 406                         error = -ENOMEM;
 407                         goto out;
 408                 }
 409                 ip = GFS2_I(jd->jd_inode);
 410                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 411                 if (error) {
 412                         kfree(lfcc);
 413                         goto out;
 414                 }
 415                 list_add(&lfcc->list, &list);
 416         }
 417
 418         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
 419                                    LM_FLAG_NOEXP, &sdp->sd_freeze_gh);
 420         if (error)
 421                 goto out;
 422
 423         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 424                 error = gfs2_jdesc_check(jd);
 425                 if (error)
 426                         break;
 427                 error = gfs2_find_jhead(jd, &lh, false);
 428                 if (error)
 429                         break;
 430                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 431                         error = -EBUSY;
 432                         break;
 433                 }
 434         }
 435
 436         if (error)
 437                 gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 438
 439 out:
 440         while (!list_empty(&list)) {
 441                 lfcc = list_first_entry(&list, struct lfcc, list);
 442                 list_del(&lfcc->list);
 443                 gfs2_glock_dq_uninit(&lfcc->gh);
 444                 kfree(lfcc);
 445         }
 446         return error;
 447 }
 448
 449 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 450 {
 451         struct gfs2_dinode *str = buf;
 452
 453         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 454         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
 455         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
 456         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
 457         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
 458         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
 459         str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
 460         str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
 461         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
 462         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
 463         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
 464         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
 465         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
 466         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
 467
 468         str->di_goal_meta = cpu_to_be64(ip->i_goal);
 469         str->di_goal_data = cpu_to_be64(ip->i_goal);
 470         str->di_generation = cpu_to_be64(ip->i_generation);
 471
 472         str->di_flags = cpu_to_be32(ip->i_diskflags);
 473         str->di_height = cpu_to_be16(ip->i_height);
 474         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
 475                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
 476                                              GFS2_FORMAT_DE : 0);
 477         str->di_depth = cpu_to_be16(ip->i_depth);
 478         str->di_entries = cpu_to_be32(ip->i_entries);
 479
 480         str->di_eattr = cpu_to_be64(ip->i_eattr);
 481         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
 482         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
 483         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
 484 }
 485
 486 /**
 487  * gfs2_write_inode - Make sure the inode is stable on the disk
 488  * @inode: The inode
 489  * @wbc: The writeback control structure
 490  *
 491  * Returns: errno
 492  */
 493
 494 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 495 {
 496         struct gfs2_inode *ip = GFS2_I(inode);
 497         struct gfs2_sbd *sdp = GFS2_SB(inode);
 498         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
 499         struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
 500         int ret = 0;
 501         bool flush_all = (wbc->sync_mode == WB_SYNC_ALL || gfs2_is_jdata(ip));
 502
 503         if (flush_all)
 504                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl,
 505                                GFS2_LOG_HEAD_FLUSH_NORMAL |
 506                                GFS2_LFC_WRITE_INODE);
 507         if (bdi->wb.dirty_exceeded)
 508                 gfs2_ail1_flush(sdp, wbc);
 509         else
 510                 filemap_fdatawrite(metamapping);
 511         if (flush_all)
 512                 ret = filemap_fdatawait(metamapping);
 513         if (ret)
 514                 mark_inode_dirty_sync(inode);
 515         else {
 516                 spin_lock(&inode->i_lock);
 517                 if (!(inode->i_flags & I_DIRTY))
 518                         gfs2_ordered_del_inode(ip);
 519                 spin_unlock(&inode->i_lock);
 520         }
 521         return ret;
 522 }
 523
 524 /**
 525  * gfs2_dirty_inode - check for atime updates
 526  * @inode: The inode in question
 527  * @flags: The type of dirty
 528  *
 529  * Unfortunately it can be called under any combination of inode
 530  * glock and transaction lock, so we have to check carefully.
 531  *
 532  * At the moment this deals only with atime - it should be possible
 533  * to expand that role in future, once a review of the locking has
 534  * been carried out.
 535  */
 536
 537 static void gfs2_dirty_inode(struct inode *inode, int flags)
 538 {
 539         struct gfs2_inode *ip = GFS2_I(inode);
 540         struct gfs2_sbd *sdp = GFS2_SB(inode);
 541         struct buffer_head *bh;
 542         struct gfs2_holder gh;
 543         int need_unlock = 0;
 544         int need_endtrans = 0;
 545         int ret;
 546
 547         if (unlikely(gfs2_withdrawn(sdp)))
 548                 return;
 549         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 550                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 551                 if (ret) {
 552                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
 553                         gfs2_dump_glock(NULL, ip->i_gl, true);
 554                         return;
 555                 }
 556                 need_unlock = 1;
 557         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
 558                 return;
 559
 560         if (current->journal_info == NULL) {
 561                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 562                 if (ret) {
 563                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
 564                         goto out;
 565                 }
 566                 need_endtrans = 1;
 567         }
 568
 569         ret = gfs2_meta_inode_buffer(ip, &bh);
 570         if (ret == 0) {
 571                 gfs2_trans_add_meta(ip->i_gl, bh);
 572                 gfs2_dinode_out(ip, bh->b_data);
 573                 brelse(bh);
 574         }
 575
 576         if (need_endtrans)
 577                 gfs2_trans_end(sdp);
 578 out:
 579         if (need_unlock)
 580                 gfs2_glock_dq_uninit(&gh);
 581 }
 582
 583 /**
 584  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 585  * @sdp: the filesystem
 586  *
 587  * Returns: errno
 588  */
 589
 590 void gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 591 {
 592         int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 593
 594         gfs2_flush_delete_work(sdp);
 595         if (!log_write_allowed && current == sdp->sd_quotad_process)
 596                 fs_warn(sdp, "The quotad daemon is withdrawing.\n");
 597         else if (sdp->sd_quotad_process)
 598                 kthread_stop(sdp->sd_quotad_process);
 599         sdp->sd_quotad_process = NULL;
 600
 601         if (!log_write_allowed && current == sdp->sd_logd_process)
 602                 fs_warn(sdp, "The logd daemon is withdrawing.\n");
 603         else if (sdp->sd_logd_process)
 604                 kthread_stop(sdp->sd_logd_process);
 605         sdp->sd_logd_process = NULL;
 606
 607         if (log_write_allowed) {
 608                 gfs2_quota_sync(sdp->sd_vfs, 0);
 609                 gfs2_statfs_sync(sdp->sd_vfs, 0);
 610
 611                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 612                                GFS2_LFC_MAKE_FS_RO);
 613                 wait_event_timeout(sdp->sd_log_waitq,
 614                                    gfs2_log_is_empty(sdp),
 615                                    HZ * 5);
 616                 gfs2_assert_warn(sdp, gfs2_log_is_empty(sdp));
 617         } else {
 618                 wait_event_timeout(sdp->sd_log_waitq,
 619                                    gfs2_log_is_empty(sdp),
 620                                    HZ * 5);
 621         }
 622         gfs2_quota_cleanup(sdp);
 623
 624         if (!log_write_allowed)
 625                 sdp->sd_vfs->s_flags |= SB_RDONLY;
 626 }
 627
 628 /**
 629  * gfs2_put_super - Unmount the filesystem
 630  * @sb: The VFS superblock
 631  *
 632  */
 633
 634 static void gfs2_put_super(struct super_block *sb)
 635 {
 636         struct gfs2_sbd *sdp = sb->s_fs_info;
 637         struct gfs2_jdesc *jd;
 638
 639         /* No more recovery requests */
 640         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 641         smp_mb();
 642
 643         /* Wait on outstanding recovery */
 644 restart:
 645         spin_lock(&sdp->sd_jindex_spin);
 646         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 647                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 648                         continue;
 649                 spin_unlock(&sdp->sd_jindex_spin);
 650                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 651                             TASK_UNINTERRUPTIBLE);
 652                 goto restart;
 653         }
 654         spin_unlock(&sdp->sd_jindex_spin);
 655
 656         if (!sb_rdonly(sb)) {
 657                 gfs2_make_fs_ro(sdp);
 658         }
 659         WARN_ON(gfs2_withdrawing(sdp));
 660
 661         /*  At this point, we're through modifying the disk  */
 662
 663         /*  Release stuff  */
 664
 665         iput(sdp->sd_jindex);
 666         iput(sdp->sd_statfs_inode);
 667         iput(sdp->sd_rindex);
 668         iput(sdp->sd_quota_inode);
 669
 670         gfs2_glock_put(sdp->sd_rename_gl);
 671         gfs2_glock_put(sdp->sd_freeze_gl);
 672
 673         if (!sdp->sd_args.ar_spectator) {
 674                 if (gfs2_holder_initialized(&sdp->sd_journal_gh))
 675                         gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 676                 if (gfs2_holder_initialized(&sdp->sd_jinode_gh))
 677                         gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 678                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 679                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 680                 free_local_statfs_inodes(sdp);
 681                 iput(sdp->sd_qc_inode);
 682         }
 683
 684         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 685         gfs2_clear_rgrpd(sdp);
 686         gfs2_jindex_free(sdp);
 687         /*  Take apart glock structures and buffer lists  */
 688         gfs2_gl_hash_clear(sdp);
 689         truncate_inode_pages_final(&sdp->sd_aspace);
 690         gfs2_delete_debugfs_file(sdp);
 691         /*  Unmount the locking protocol  */
 692         gfs2_lm_unmount(sdp);
 693
 694         /*  At this point, we're through participating in the lockspace  */
 695         gfs2_sys_fs_del(sdp);
 696         free_sbd(sdp);
 697 }
 698
 699 /**
 700  * gfs2_sync_fs - sync the filesystem
 701  * @sb: the superblock
 702  * @wait: true to wait for completion
 703  *
 704  * Flushes the log to disk.
 705  */
 706
 707 static int gfs2_sync_fs(struct super_block *sb, int wait)
 708 {
 709         struct gfs2_sbd *sdp = sb->s_fs_info;
 710
 711         gfs2_quota_sync(sb, -1);
 712         if (wait)
 713                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 714                                GFS2_LFC_SYNC_FS);
 715         return sdp->sd_log_error;
 716 }
 717
 718 void gfs2_freeze_func(struct work_struct *work)
 719 {
 720         int error;
 721         struct gfs2_holder freeze_gh;
 722         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
 723         struct super_block *sb = sdp->sd_vfs;
 724
 725         atomic_inc(&sb->s_active);
 726         error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 727         if (error) {
 728                 gfs2_assert_withdraw(sdp, 0);
 729         } else {
 730                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 731                 error = thaw_super(sb);
 732                 if (error) {
 733                         fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n",
 734                                 error);
 735                         gfs2_assert_withdraw(sdp, 0);
 736                 }
 737                 gfs2_freeze_unlock(&freeze_gh);
 738         }
 739         deactivate_super(sb);
 740         clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
 741         wake_up_bit(&sdp->sd_flags, SDF_FS_FROZEN);
 742         return;
 743 }
 744
 745 /**
 746  * gfs2_freeze - prevent further writes to the filesystem
 747  * @sb: the VFS structure for the filesystem
 748  *
 749  */
 750
 751 static int gfs2_freeze(struct super_block *sb)
 752 {
 753         struct gfs2_sbd *sdp = sb->s_fs_info;
 754         int error;
 755
 756         mutex_lock(&sdp->sd_freeze_mutex);
 757         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN) {
 758                 error = -EBUSY;
 759                 goto out;
 760         }
 761
 762         for (;;) {
 763                 if (gfs2_withdrawn(sdp)) {
 764                         error = -EINVAL;
 765                         goto out;
 766                 }
 767
 768                 error = gfs2_lock_fs_check_clean(sdp);
 769                 if (!error)
 770                         break;
 771
 772                 if (error == -EBUSY)
 773                         fs_err(sdp, "waiting for recovery before freeze\n");
 774                 else if (error == -EIO) {
 775                         fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
 776                                "to recovery error.\n");
 777                         goto out;
 778                 } else {
 779                         fs_err(sdp, "error freezing FS: %d\n", error);
 780                 }
 781                 fs_err(sdp, "retrying...\n");
 782                 msleep(1000);
 783         }
 784         set_bit(SDF_FS_FROZEN, &sdp->sd_flags);
 785 out:
 786         mutex_unlock(&sdp->sd_freeze_mutex);
 787         return error;
 788 }
 789
 790 /**
 791  * gfs2_unfreeze - reallow writes to the filesystem
 792  * @sb: the VFS structure for the filesystem
 793  *
 794  */
 795
 796 static int gfs2_unfreeze(struct super_block *sb)
 797 {
 798         struct gfs2_sbd *sdp = sb->s_fs_info;
 799
 800         mutex_lock(&sdp->sd_freeze_mutex);
 801         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
 802             !gfs2_holder_initialized(&sdp->sd_freeze_gh)) {
 803                 mutex_unlock(&sdp->sd_freeze_mutex);
 804                 return -EINVAL;
 805         }
 806
 807         gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 808         mutex_unlock(&sdp->sd_freeze_mutex);
 809         return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 810 }
 811
 812 /**
 813  * statfs_slow_fill - fill in the sg for a given RG
 814  * @rgd: the RG
 815  * @sc: the sc structure
 816  *
 817  * Returns: 0 on success, -ESTALE if the LVB is invalid
 818  */
 819
 820 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 821                             struct gfs2_statfs_change_host *sc)
 822 {
 823         gfs2_rgrp_verify(rgd);
 824         sc->sc_total += rgd->rd_data;
 825         sc->sc_free += rgd->rd_free;
 826         sc->sc_dinodes += rgd->rd_dinodes;
 827         return 0;
 828 }
 829
 830 /**
 831  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 832  * @sdp: the filesystem
 833  * @sc: the sc info that will be returned
 834  *
 835  * Any error (other than a signal) will cause this routine to fall back
 836  * to the synchronous version.
 837  *
 838  * FIXME: This really shouldn't busy wait like this.
 839  *
 840  * Returns: errno
 841  */
 842
 843 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 844 {
 845         struct gfs2_rgrpd *rgd_next;
 846         struct gfs2_holder *gha, *gh;
 847         unsigned int slots = 64;
 848         unsigned int x;
 849         int done;
 850         int error = 0, err;
 851
 852         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 853         gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 854         if (!gha)
 855                 return -ENOMEM;
 856         for (x = 0; x < slots; x++)
 857                 gfs2_holder_mark_uninitialized(gha + x);
 858
 859         rgd_next = gfs2_rgrpd_get_first(sdp);
 860
 861         for (;;) {
 862                 done = 1;
 863
 864                 for (x = 0; x < slots; x++) {
 865                         gh = gha + x;
 866
 867                         if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
 868                                 err = gfs2_glock_wait(gh);
 869                                 if (err) {
 870                                         gfs2_holder_uninit(gh);
 871                                         error = err;
 872                                 } else {
 873                                         if (!error) {
 874                                                 struct gfs2_rgrpd *rgd =
 875                                                         gfs2_glock2rgrp(gh->gh_gl);
 876
 877                                                 error = statfs_slow_fill(rgd, sc);
 878                                         }
 879                                         gfs2_glock_dq_uninit(gh);
 880                                 }
 881                         }
 882
 883                         if (gfs2_holder_initialized(gh))
 884                                 done = 0;
 885                         else if (rgd_next && !error) {
 886                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 887                                                            LM_ST_SHARED,
 888                                                            GL_ASYNC,
 889                                                            gh);
 890                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 891                                 done = 0;
 892                         }
 893
 894                         if (signal_pending(current))
 895                                 error = -ERESTARTSYS;
 896                 }
 897
 898                 if (done)
 899                         break;
 900
 901                 yield();
 902         }
 903
 904         kfree(gha);
 905         return error;
 906 }
 907
 908 /**
 909  * gfs2_statfs_i - Do a statfs
 910  * @sdp: the filesystem
 911  * @sc: the sc structure
 912  *
 913  * Returns: errno
 914  */
 915
 916 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 917 {
 918         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 919         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 920
 921         spin_lock(&sdp->sd_statfs_spin);
 922
 923         *sc = *m_sc;
 924         sc->sc_total += l_sc->sc_total;
 925         sc->sc_free += l_sc->sc_free;
 926         sc->sc_dinodes += l_sc->sc_dinodes;
 927
 928         spin_unlock(&sdp->sd_statfs_spin);
 929
 930         if (sc->sc_free < 0)
 931                 sc->sc_free = 0;
 932         if (sc->sc_free > sc->sc_total)
 933                 sc->sc_free = sc->sc_total;
 934         if (sc->sc_dinodes < 0)
 935                 sc->sc_dinodes = 0;
 936
 937         return 0;
 938 }
 939
 940 /**
 941  * gfs2_statfs - Gather and return stats about the filesystem
 942  * @dentry: The name of the link
 943  * @buf: The buffer
 944  *
 945  * Returns: 0 on success or error code
 946  */
 947
 948 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 949 {
 950         struct super_block *sb = dentry->d_sb;
 951         struct gfs2_sbd *sdp = sb->s_fs_info;
 952         struct gfs2_statfs_change_host sc;
 953         int error;
 954
 955         error = gfs2_rindex_update(sdp);
 956         if (error)
 957                 return error;
 958
 959         if (gfs2_tune_get(sdp, gt_statfs_slow))
 960                 error = gfs2_statfs_slow(sdp, &sc);
 961         else
 962                 error = gfs2_statfs_i(sdp, &sc);
 963
 964         if (error)
 965                 return error;
 966
 967         buf->f_type = GFS2_MAGIC;
 968         buf->f_bsize = sdp->sd_sb.sb_bsize;
 969         buf->f_blocks = sc.sc_total;
 970         buf->f_bfree = sc.sc_free;
 971         buf->f_bavail = sc.sc_free;
 972         buf->f_files = sc.sc_dinodes + sc.sc_free;
 973         buf->f_ffree = sc.sc_free;
 974         buf->f_namelen = GFS2_FNAMESIZE;
 975
 976         return 0;
 977 }
 978
 979 /**
 980  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 981  * @inode: The inode to drop
 982  *
 983  * If we've received a callback on an iopen lock then it's because a
 984  * remote node tried to deallocate the inode but failed due to this node
 985  * still having the inode open. Here we mark the link count zero
 986  * since we know that it must have reached zero if the GLF_DEMOTE flag
 987  * is set on the iopen glock. If we didn't do a disk read since the
 988  * remote node removed the final link then we might otherwise miss
 989  * this event. This check ensures that this node will deallocate the
 990  * inode's blocks, or alternatively pass the baton on to another
 991  * node for later deallocation.
 992  */
 993
 994 static int gfs2_drop_inode(struct inode *inode)
 995 {
 996         struct gfs2_inode *ip = GFS2_I(inode);
 997
 998         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) &&
 999             inode->i_nlink &&
1000             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1001                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1002                 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
1003                         clear_nlink(inode);
1004         }
1005
1006         /*
1007          * When under memory pressure when an inode's link count has dropped to
1008          * zero, defer deleting the inode to the delete workqueue.  This avoids
1009          * calling into DLM under memory pressure, which can deadlock.
1010          */
1011         if (!inode->i_nlink &&
1012             unlikely(current->flags & PF_MEMALLOC) &&
1013             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1014                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1015
1016                 gfs2_glock_hold(gl);
1017                 if (!gfs2_queue_delete_work(gl, 0))
1018                         gfs2_glock_queue_put(gl);
1019                 return false;
1020         }
1021
1022         return generic_drop_inode(inode);
1023 }
1024
1025 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1026 {
1027         do {
1028                 if (d1 == d2)
1029                         return 1;
1030                 d1 = d1->d_parent;
1031         } while (!IS_ROOT(d1));
1032         return 0;
1033 }
1034
1035 /**
1036  * gfs2_show_options - Show mount options for /proc/mounts
1037  * @s: seq_file structure
1038  * @root: root of this (sub)tree
1039  *
1040  * Returns: 0 on success or error code
1041  */
1042
1043 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1044 {
1045         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1046         struct gfs2_args *args = &sdp->sd_args;
1047         int val;
1048
1049         if (is_ancestor(root, sdp->sd_master_dir))
1050                 seq_puts(s, ",meta");
1051         if (args->ar_lockproto[0])
1052                 seq_show_option(s, "lockproto", args->ar_lockproto);
1053         if (args->ar_locktable[0])
1054                 seq_show_option(s, "locktable", args->ar_locktable);
1055         if (args->ar_hostdata[0])
1056                 seq_show_option(s, "hostdata", args->ar_hostdata);
1057         if (args->ar_spectator)
1058                 seq_puts(s, ",spectator");
1059         if (args->ar_localflocks)
1060                 seq_puts(s, ",localflocks");
1061         if (args->ar_debug)
1062                 seq_puts(s, ",debug");
1063         if (args->ar_posix_acl)
1064                 seq_puts(s, ",acl");
1065         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1066                 char *state;
1067                 switch (args->ar_quota) {
1068                 case GFS2_QUOTA_OFF:
1069                         state = "off";
1070                         break;
1071                 case GFS2_QUOTA_ACCOUNT:
1072                         state = "account";
1073                         break;
1074                 case GFS2_QUOTA_ON:
1075                         state = "on";
1076                         break;
1077                 default:
1078                         state = "unknown";
1079                         break;
1080                 }
1081                 seq_printf(s, ",quota=%s", state);
1082         }
1083         if (args->ar_suiddir)
1084                 seq_puts(s, ",suiddir");
1085         if (args->ar_data != GFS2_DATA_DEFAULT) {
1086                 char *state;
1087                 switch (args->ar_data) {
1088                 case GFS2_DATA_WRITEBACK:
1089                         state = "writeback";
1090                         break;
1091                 case GFS2_DATA_ORDERED:
1092                         state = "ordered";
1093                         break;
1094                 default:
1095                         state = "unknown";
1096                         break;
1097                 }
1098                 seq_printf(s, ",data=%s", state);
1099         }
1100         if (args->ar_discard)
1101                 seq_puts(s, ",discard");
1102         val = sdp->sd_tune.gt_logd_secs;
1103         if (val != 30)
1104                 seq_printf(s, ",commit=%d", val);
1105         val = sdp->sd_tune.gt_statfs_quantum;
1106         if (val != 30)
1107                 seq_printf(s, ",statfs_quantum=%d", val);
1108         else if (sdp->sd_tune.gt_statfs_slow)
1109                 seq_puts(s, ",statfs_quantum=0");
1110         val = sdp->sd_tune.gt_quota_quantum;
1111         if (val != 60)
1112                 seq_printf(s, ",quota_quantum=%d", val);
1113         if (args->ar_statfs_percent)
1114                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1115         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1116                 const char *state;
1117
1118                 switch (args->ar_errors) {
1119                 case GFS2_ERRORS_WITHDRAW:
1120                         state = "withdraw";
1121                         break;
1122                 case GFS2_ERRORS_PANIC:
1123                         state = "panic";
1124                         break;
1125                 default:
1126                         state = "unknown";
1127                         break;
1128                 }
1129                 seq_printf(s, ",errors=%s", state);
1130         }
1131         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1132                 seq_puts(s, ",nobarrier");
1133         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1134                 seq_puts(s, ",demote_interface_used");
1135         if (args->ar_rgrplvb)
1136                 seq_puts(s, ",rgrplvb");
1137         if (args->ar_loccookie)
1138                 seq_puts(s, ",loccookie");
1139         return 0;
1140 }
1141
1142 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1143 {
1144         struct inode *inode = &ip->i_inode;
1145         struct gfs2_glock *gl = ip->i_gl;
1146
1147         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1148         truncate_inode_pages(&inode->i_data, 0);
1149
1150         if (atomic_read(&gl->gl_revokes) == 0) {
1151                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1152                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1153         }
1154 }
1155
1156 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1157 {
1158         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1159         struct gfs2_rgrpd *rgd;
1160         struct gfs2_holder gh;
1161         int error;
1162
1163         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1164                 gfs2_consist_inode(ip);
1165                 return -EIO;
1166         }
1167
1168         error = gfs2_rindex_update(sdp);
1169         if (error)
1170                 return error;
1171
1172         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1173         if (error)
1174                 return error;
1175
1176         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1177         if (!rgd) {
1178                 gfs2_consist_inode(ip);
1179                 error = -EIO;
1180                 goto out_qs;
1181         }
1182
1183         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1184                                    LM_FLAG_NODE_SCOPE, &gh);
1185         if (error)
1186                 goto out_qs;
1187
1188         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1189                                  sdp->sd_jdesc->jd_blocks);
1190         if (error)
1191                 goto out_rg_gunlock;
1192
1193         gfs2_free_di(rgd, ip);
1194
1195         gfs2_final_release_pages(ip);
1196
1197         gfs2_trans_end(sdp);
1198
1199 out_rg_gunlock:
1200         gfs2_glock_dq_uninit(&gh);
1201 out_qs:
1202         gfs2_quota_unhold(ip);
1203         return error;
1204 }
1205
1206 /**
1207  * gfs2_glock_put_eventually
1208  * @gl: The glock to put
1209  *
1210  * When under memory pressure, trigger a deferred glock put to make sure we
1211  * won't call into DLM and deadlock.  Otherwise, put the glock directly.
1212  */
1213
1214 static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
1215 {
1216         if (current->flags & PF_MEMALLOC)
1217                 gfs2_glock_queue_put(gl);
1218         else
1219                 gfs2_glock_put(gl);
1220 }
1221
1222 static bool gfs2_upgrade_iopen_glock(struct inode *inode)
1223 {
1224         struct gfs2_inode *ip = GFS2_I(inode);
1225         struct gfs2_sbd *sdp = GFS2_SB(inode);
1226         struct gfs2_holder *gh = &ip->i_iopen_gh;
1227         long timeout = 5 * HZ;
1228         int error;
1229
1230         gh->gh_flags |= GL_NOCACHE;
1231         gfs2_glock_dq_wait(gh);
1232
1233         /*
1234          * If there are no other lock holders, we'll get the lock immediately.
1235          * Otherwise, the other nodes holding the lock will be notified about
1236          * our locking request.  If they don't have the inode open, they'll
1237          * evict the cached inode and release the lock.  Otherwise, if they
1238          * poke the inode glock, we'll take this as an indication that they
1239          * still need the iopen glock and that they'll take care of deleting
1240          * the inode when they're done.  As a last resort, if another node
1241          * keeps holding the iopen glock without showing any activity on the
1242          * inode glock, we'll eventually time out.
1243          *
1244          * Note that we're passing the LM_FLAG_TRY_1CB flag to the first
1245          * locking request as an optimization to notify lock holders as soon as
1246          * possible.  Without that flag, they'd be notified implicitly by the
1247          * second locking request.
1248          */
1249
1250         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, gh);
1251         error = gfs2_glock_nq(gh);
1252         if (error != GLR_TRYFAILED)
1253                 return !error;
1254
1255         gfs2_holder_reinit(LM_ST_EXCLUSIVE, GL_ASYNC | GL_NOCACHE, gh);
1256         error = gfs2_glock_nq(gh);
1257         if (error)
1258                 return false;
1259
1260         timeout = wait_event_interruptible_timeout(sdp->sd_async_glock_wait,
1261                 !test_bit(HIF_WAIT, &gh->gh_iflags) ||
1262                 test_bit(GLF_DEMOTE, &ip->i_gl->gl_flags),
1263                 timeout);
1264         if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) {
1265                 gfs2_glock_dq(gh);
1266                 return false;
1267         }
1268         return true;
1269 }
1270
1271 /**
1272  * evict_should_delete - determine whether the inode is eligible for deletion
1273  * @inode: The inode to evict
1274  * @gh: The glock holder structure
1275  *
1276  * This function determines whether the evicted inode is eligible to be deleted
1277  * and locks the inode glock.
1278  *
1279  * Returns: the fate of the dinode
1280  */
1281 static enum dinode_demise evict_should_delete(struct inode *inode,
1282                                               struct gfs2_holder *gh)
1283 {
1284         struct gfs2_inode *ip = GFS2_I(inode);
1285         struct super_block *sb = inode->i_sb;
1286         struct gfs2_sbd *sdp = sb->s_fs_info;
1287         int ret;
1288
1289         if (test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1290                 BUG_ON(!gfs2_glock_is_locked_by_me(ip->i_gl));
1291                 goto should_delete;
1292         }
1293
1294         if (test_bit(GIF_DEFERRED_DELETE, &ip->i_flags))
1295                 return SHOULD_DEFER_EVICTION;
1296
1297         /* Deletes should never happen under memory pressure anymore.  */
1298         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
1299                 return SHOULD_DEFER_EVICTION;
1300
1301         /* Must not read inode block until block type has been verified */
1302         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, gh);
1303         if (unlikely(ret)) {
1304                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1305                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1306                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1307                 return SHOULD_DEFER_EVICTION;
1308         }
1309
1310         if (gfs2_inode_already_deleted(ip->i_gl, ip->i_no_formal_ino))
1311                 return SHOULD_NOT_DELETE_DINODE;
1312         ret = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1313         if (ret)
1314                 return SHOULD_NOT_DELETE_DINODE;
1315
1316         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1317                 ret = gfs2_inode_refresh(ip);
1318                 if (ret)
1319                         return SHOULD_NOT_DELETE_DINODE;
1320         }
1321
1322         /*
1323          * The inode may have been recreated in the meantime.
1324          */
1325         if (inode->i_nlink)
1326                 return SHOULD_NOT_DELETE_DINODE;
1327
1328 should_delete:
1329         if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
1330             test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1331                 if (!gfs2_upgrade_iopen_glock(inode)) {
1332                         gfs2_holder_uninit(&ip->i_iopen_gh);
1333                         return SHOULD_NOT_DELETE_DINODE;
1334                 }
1335         }
1336         return SHOULD_DELETE_DINODE;
1337 }
1338
1339 /**
1340  * evict_unlinked_inode - delete the pieces of an unlinked evicted inode
1341  * @inode: The inode to evict
1342  */
1343 static int evict_unlinked_inode(struct inode *inode)
1344 {
1345         struct gfs2_inode *ip = GFS2_I(inode);
1346         int ret;
1347
1348         if (S_ISDIR(inode->i_mode) &&
1349             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1350                 ret = gfs2_dir_exhash_dealloc(ip);
1351                 if (ret)
1352                         goto out;
1353         }
1354
1355         if (ip->i_eattr) {
1356                 ret = gfs2_ea_dealloc(ip);
1357                 if (ret)
1358                         goto out;
1359         }
1360
1361         if (!gfs2_is_stuffed(ip)) {
1362                 ret = gfs2_file_dealloc(ip);
1363                 if (ret)
1364                         goto out;
1365         }
1366
1367         /* We're about to clear the bitmap for the dinode, but as soon as we
1368            do, gfs2_create_inode can create another inode at the same block
1369            location and try to set gl_object again. We clear gl_object here so
1370            that subsequent inode creates don't see an old gl_object. */
1371         glock_clear_object(ip->i_gl, ip);
1372         ret = gfs2_dinode_dealloc(ip);
1373         gfs2_inode_remember_delete(ip->i_gl, ip->i_no_formal_ino);
1374 out:
1375         return ret;
1376 }
1377
1378 /*
1379  * evict_linked_inode - evict an inode whose dinode has not been unlinked
1380  * @inode: The inode to evict
1381  */
1382 static int evict_linked_inode(struct inode *inode)
1383 {
1384         struct super_block *sb = inode->i_sb;
1385         struct gfs2_sbd *sdp = sb->s_fs_info;
1386         struct gfs2_inode *ip = GFS2_I(inode);
1387         struct address_space *metamapping;
1388         int ret;
1389
1390         gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
1391                        GFS2_LFC_EVICT_INODE);
1392         metamapping = gfs2_glock2aspace(ip->i_gl);
1393         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1394                 filemap_fdatawrite(metamapping);
1395                 filemap_fdatawait(metamapping);
1396         }
1397         write_inode_now(inode, 1);
1398         gfs2_ail_flush(ip->i_gl, 0);
1399
1400         ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1401         if (ret)
1402                 return ret;
1403
1404         /* Needs to be done before glock release & also in a transaction */
1405         truncate_inode_pages(&inode->i_data, 0);
1406         truncate_inode_pages(metamapping, 0);
1407         gfs2_trans_end(sdp);
1408         return 0;
1409 }
1410
1411 /**
1412  * gfs2_evict_inode - Remove an inode from cache
1413  * @inode: The inode to evict
1414  *
1415  * There are three cases to consider:
1416  * 1. i_nlink == 0, we are final opener (and must deallocate)
1417  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1418  * 3. i_nlink > 0
1419  *
1420  * If the fs is read only, then we have to treat all cases as per #3
1421  * since we are unable to do any deallocation. The inode will be
1422  * deallocated by the next read/write node to attempt an allocation
1423  * in the same resource group
1424  *
1425  * We have to (at the moment) hold the inodes main lock to cover
1426  * the gap between unlocking the shared lock on the iopen lock and
1427  * taking the exclusive lock. I'd rather do a shared -> exclusive
1428  * conversion on the iopen lock, but we can change that later. This
1429  * is safe, just less efficient.
1430  */
1431
1432 static void gfs2_evict_inode(struct inode *inode)
1433 {
1434         struct super_block *sb = inode->i_sb;
1435         struct gfs2_sbd *sdp = sb->s_fs_info;
1436         struct gfs2_inode *ip = GFS2_I(inode);
1437         struct gfs2_holder gh;
1438         int ret;
1439
1440         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1441                 clear_inode(inode);
1442                 return;
1443         }
1444
1445         if (inode->i_nlink || sb_rdonly(sb))
1446                 goto out;
1447
1448         gfs2_holder_mark_uninitialized(&gh);
1449         ret = evict_should_delete(inode, &gh);
1450         if (ret == SHOULD_DEFER_EVICTION)
1451                 goto out;
1452         if (ret == SHOULD_DELETE_DINODE)
1453                 ret = evict_unlinked_inode(inode);
1454         else
1455                 ret = evict_linked_inode(inode);
1456
1457         if (gfs2_rs_active(&ip->i_res))
1458                 gfs2_rs_deltree(&ip->i_res);
1459
1460         if (gfs2_holder_initialized(&gh)) {
1461                 glock_clear_object(ip->i_gl, ip);
1462                 gfs2_glock_dq_uninit(&gh);
1463         }
1464         if (ret && ret != GLR_TRYFAILED && ret != -EROFS)
1465                 fs_warn(sdp, "gfs2_evict_inode: %d\n", ret);
1466 out:
1467         truncate_inode_pages_final(&inode->i_data);
1468         if (ip->i_qadata)
1469                 gfs2_assert_warn(sdp, ip->i_qadata->qa_ref == 0);
1470         gfs2_rs_delete(ip, NULL);
1471         gfs2_ordered_del_inode(ip);
1472         clear_inode(inode);
1473         gfs2_dir_hash_inval(ip);
1474         if (ip->i_gl) {
1475                 glock_clear_object(ip->i_gl, ip);
1476                 wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
1477                 gfs2_glock_add_to_lru(ip->i_gl);
1478                 gfs2_glock_put_eventually(ip->i_gl);
1479                 ip->i_gl = NULL;
1480         }
1481         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1482                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1483
1484                 glock_clear_object(gl, ip);
1485                 if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1486                         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1487                         gfs2_glock_dq(&ip->i_iopen_gh);
1488                 }
1489                 gfs2_glock_hold(gl);
1490                 gfs2_holder_uninit(&ip->i_iopen_gh);
1491                 gfs2_glock_put_eventually(gl);
1492         }
1493 }
1494
1495 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1496 {
1497         struct gfs2_inode *ip;
1498
1499         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1500         if (!ip)
1501                 return NULL;
1502         ip->i_flags = 0;
1503         ip->i_gl = NULL;
1504         gfs2_holder_mark_uninitialized(&ip->i_iopen_gh);
1505         memset(&ip->i_res, 0, sizeof(ip->i_res));
1506         RB_CLEAR_NODE(&ip->i_res.rs_node);
1507         ip->i_rahead = 0;
1508         return &ip->i_inode;
1509 }
1510
1511 static void gfs2_free_inode(struct inode *inode)
1512 {
1513         kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
1514 }
1515
1516 extern void free_local_statfs_inodes(struct gfs2_sbd *sdp)
1517 {
1518         struct local_statfs_inode *lsi, *safe;
1519
1520         /* Run through the statfs inodes list to iput and free memory */
1521         list_for_each_entry_safe(lsi, safe, &sdp->sd_sc_inodes_list, si_list) {
1522                 if (lsi->si_jid == sdp->sd_jdesc->jd_jid)
1523                         sdp->sd_sc_inode = NULL; /* belongs to this node */
1524                 if (lsi->si_sc_inode)
1525                         iput(lsi->si_sc_inode);
1526                 list_del(&lsi->si_list);
1527                 kfree(lsi);
1528         }
1529 }
1530
1531 extern struct inode *find_local_statfs_inode(struct gfs2_sbd *sdp,
1532                                              unsigned int index)
1533 {
1534         struct local_statfs_inode *lsi;
1535
1536         /* Return the local (per node) statfs inode in the
1537          * sdp->sd_sc_inodes_list corresponding to the 'index'. */
1538         list_for_each_entry(lsi, &sdp->sd_sc_inodes_list, si_list) {
1539                 if (lsi->si_jid == index)
1540                         return lsi->si_sc_inode;
1541         }
1542         return NULL;
1543 }
1544
1545 const struct super_operations gfs2_super_ops = {
1546         .alloc_inode            = gfs2_alloc_inode,
1547         .free_inode             = gfs2_free_inode,
1548         .write_inode            = gfs2_write_inode,
1549         .dirty_inode            = gfs2_dirty_inode,
1550         .evict_inode            = gfs2_evict_inode,
1551         .put_super              = gfs2_put_super,
1552         .sync_fs                = gfs2_sync_fs,
1553         .freeze_super           = gfs2_freeze,
1554         .thaw_super             = gfs2_unfreeze,
1555         .statfs                 = gfs2_statfs,
1556         .drop_inode             = gfs2_drop_inode,
1557         .show_options           = gfs2_show_options,
1558 };
1559