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                 return error;
 167
 168         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 169         if (gfs2_withdrawn(sdp)) {
 170                 error = -EIO;
 171                 goto fail;
 172         }
 173
 174         error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
 175         if (error || gfs2_withdrawn(sdp))
 176                 goto fail;
 177
 178         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 179                 gfs2_consist(sdp);
 180                 error = -EIO;
 181                 goto fail;
 182         }
 183
 184         /*  Initialize some head of the log stuff  */
 185         sdp->sd_log_sequence = head.lh_sequence + 1;
 186         gfs2_log_pointers_init(sdp, head.lh_blkno);
 187
 188         error = gfs2_quota_init(sdp);
 189         if (error || gfs2_withdrawn(sdp))
 190                 goto fail;
 191
 192         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 193
 194         return 0;
 195
 196 fail:
 197         if (sdp->sd_quotad_process)
 198                 kthread_stop(sdp->sd_quotad_process);
 199         sdp->sd_quotad_process = NULL;
 200         if (sdp->sd_logd_process)
 201                 kthread_stop(sdp->sd_logd_process);
 202         sdp->sd_logd_process = NULL;
 203         return error;
 204 }
 205
 206 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 207 {
 208         const struct gfs2_statfs_change *str = buf;
 209
 210         sc->sc_total = be64_to_cpu(str->sc_total);
 211         sc->sc_free = be64_to_cpu(str->sc_free);
 212         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 213 }
 214
 215 void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 216 {
 217         struct gfs2_statfs_change *str = buf;
 218
 219         str->sc_total = cpu_to_be64(sc->sc_total);
 220         str->sc_free = cpu_to_be64(sc->sc_free);
 221         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 222 }
 223
 224 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 225 {
 226         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 227         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 228         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 229         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 230         struct buffer_head *m_bh, *l_bh;
 231         struct gfs2_holder gh;
 232         int error;
 233
 234         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 235                                    &gh);
 236         if (error)
 237                 return error;
 238
 239         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 240         if (error)
 241                 goto out;
 242
 243         if (sdp->sd_args.ar_spectator) {
 244                 spin_lock(&sdp->sd_statfs_spin);
 245                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 246                                       sizeof(struct gfs2_dinode));
 247                 spin_unlock(&sdp->sd_statfs_spin);
 248         } else {
 249                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 250                 if (error)
 251                         goto out_m_bh;
 252
 253                 spin_lock(&sdp->sd_statfs_spin);
 254                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 255                                       sizeof(struct gfs2_dinode));
 256                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 257                                       sizeof(struct gfs2_dinode));
 258                 spin_unlock(&sdp->sd_statfs_spin);
 259
 260                 brelse(l_bh);
 261         }
 262
 263 out_m_bh:
 264         brelse(m_bh);
 265 out:
 266         gfs2_glock_dq_uninit(&gh);
 267         return 0;
 268 }
 269
 270 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 271                         s64 dinodes)
 272 {
 273         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 274         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 275         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 276         struct buffer_head *l_bh;
 277         s64 x, y;
 278         int need_sync = 0;
 279         int error;
 280
 281         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 282         if (error)
 283                 return;
 284
 285         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 286
 287         spin_lock(&sdp->sd_statfs_spin);
 288         l_sc->sc_total += total;
 289         l_sc->sc_free += free;
 290         l_sc->sc_dinodes += dinodes;
 291         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 292         if (sdp->sd_args.ar_statfs_percent) {
 293                 x = 100 * l_sc->sc_free;
 294                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 295                 if (x >= y || x <= -y)
 296                         need_sync = 1;
 297         }
 298         spin_unlock(&sdp->sd_statfs_spin);
 299
 300         brelse(l_bh);
 301         if (need_sync)
 302                 gfs2_wake_up_statfs(sdp);
 303 }
 304
 305 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 306                    struct buffer_head *l_bh)
 307 {
 308         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 309         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 310         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 311         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 312
 313         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 314         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
 315
 316         spin_lock(&sdp->sd_statfs_spin);
 317         m_sc->sc_total += l_sc->sc_total;
 318         m_sc->sc_free += l_sc->sc_free;
 319         m_sc->sc_dinodes += l_sc->sc_dinodes;
 320         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 321         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 322                0, sizeof(struct gfs2_statfs_change));
 323         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 324         spin_unlock(&sdp->sd_statfs_spin);
 325 }
 326
 327 int gfs2_statfs_sync(struct super_block *sb, int type)
 328 {
 329         struct gfs2_sbd *sdp = sb->s_fs_info;
 330         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 331         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 332         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 333         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 334         struct gfs2_holder gh;
 335         struct buffer_head *m_bh, *l_bh;
 336         int error;
 337
 338         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 339                                    &gh);
 340         if (error)
 341                 goto out;
 342
 343         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 344         if (error)
 345                 goto out_unlock;
 346
 347         spin_lock(&sdp->sd_statfs_spin);
 348         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 349                               sizeof(struct gfs2_dinode));
 350         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 351                 spin_unlock(&sdp->sd_statfs_spin);
 352                 goto out_bh;
 353         }
 354         spin_unlock(&sdp->sd_statfs_spin);
 355
 356         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 357         if (error)
 358                 goto out_bh;
 359
 360         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 361         if (error)
 362                 goto out_bh2;
 363
 364         update_statfs(sdp, m_bh, l_bh);
 365         sdp->sd_statfs_force_sync = 0;
 366
 367         gfs2_trans_end(sdp);
 368
 369 out_bh2:
 370         brelse(l_bh);
 371 out_bh:
 372         brelse(m_bh);
 373 out_unlock:
 374         gfs2_glock_dq_uninit(&gh);
 375 out:
 376         return error;
 377 }
 378
 379 struct lfcc {
 380         struct list_head list;
 381         struct gfs2_holder gh;
 382 };
 383
 384 /**
 385  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 386  *                            journals are clean
 387  * @sdp: the file system
 388  * @state: the state to put the transaction lock into
 389  * @t_gh: the hold on the transaction lock
 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 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 591 {
 592         int error = 0;
 593         int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 594
 595         gfs2_flush_delete_work(sdp);
 596         if (!log_write_allowed && current == sdp->sd_quotad_process)
 597                 fs_warn(sdp, "The quotad daemon is withdrawing.\n");
 598         else if (sdp->sd_quotad_process)
 599                 kthread_stop(sdp->sd_quotad_process);
 600         sdp->sd_quotad_process = NULL;
 601
 602         if (!log_write_allowed && current == sdp->sd_logd_process)
 603                 fs_warn(sdp, "The logd daemon is withdrawing.\n");
 604         else if (sdp->sd_logd_process)
 605                 kthread_stop(sdp->sd_logd_process);
 606         sdp->sd_logd_process = NULL;
 607
 608         if (log_write_allowed) {
 609                 gfs2_quota_sync(sdp->sd_vfs, 0);
 610                 gfs2_statfs_sync(sdp->sd_vfs, 0);
 611
 612                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 613                                GFS2_LFC_MAKE_FS_RO);
 614                 wait_event_timeout(sdp->sd_log_waitq,
 615                                    gfs2_log_is_empty(sdp),
 616                                    HZ * 5);
 617                 gfs2_assert_warn(sdp, gfs2_log_is_empty(sdp));
 618         } else {
 619                 wait_event_timeout(sdp->sd_log_waitq,
 620                                    gfs2_log_is_empty(sdp),
 621                                    HZ * 5);
 622         }
 623         gfs2_quota_cleanup(sdp);
 624
 625         if (!log_write_allowed)
 626                 sdp->sd_vfs->s_flags |= SB_RDONLY;
 627
 628         return error;
 629 }
 630
 631 /**
 632  * gfs2_put_super - Unmount the filesystem
 633  * @sb: The VFS superblock
 634  *
 635  */
 636
 637 static void gfs2_put_super(struct super_block *sb)
 638 {
 639         struct gfs2_sbd *sdp = sb->s_fs_info;
 640         int error;
 641         struct gfs2_jdesc *jd;
 642
 643         /* No more recovery requests */
 644         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 645         smp_mb();
 646
 647         /* Wait on outstanding recovery */
 648 restart:
 649         spin_lock(&sdp->sd_jindex_spin);
 650         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 651                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 652                         continue;
 653                 spin_unlock(&sdp->sd_jindex_spin);
 654                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 655                             TASK_UNINTERRUPTIBLE);
 656                 goto restart;
 657         }
 658         spin_unlock(&sdp->sd_jindex_spin);
 659
 660         if (!sb_rdonly(sb)) {
 661                 error = gfs2_make_fs_ro(sdp);
 662                 if (error)
 663                         gfs2_io_error(sdp);
 664         }
 665         WARN_ON(gfs2_withdrawing(sdp));
 666
 667         /*  At this point, we're through modifying the disk  */
 668
 669         /*  Release stuff  */
 670
 671         iput(sdp->sd_jindex);
 672         iput(sdp->sd_statfs_inode);
 673         iput(sdp->sd_rindex);
 674         iput(sdp->sd_quota_inode);
 675
 676         gfs2_glock_put(sdp->sd_rename_gl);
 677         gfs2_glock_put(sdp->sd_freeze_gl);
 678
 679         if (!sdp->sd_args.ar_spectator) {
 680                 if (gfs2_holder_initialized(&sdp->sd_journal_gh))
 681                         gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 682                 if (gfs2_holder_initialized(&sdp->sd_jinode_gh))
 683                         gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 684                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 685                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 686                 free_local_statfs_inodes(sdp);
 687                 iput(sdp->sd_qc_inode);
 688         }
 689
 690         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 691         gfs2_clear_rgrpd(sdp);
 692         gfs2_jindex_free(sdp);
 693         /*  Take apart glock structures and buffer lists  */
 694         gfs2_gl_hash_clear(sdp);
 695         truncate_inode_pages_final(&sdp->sd_aspace);
 696         gfs2_delete_debugfs_file(sdp);
 697         /*  Unmount the locking protocol  */
 698         gfs2_lm_unmount(sdp);
 699
 700         /*  At this point, we're through participating in the lockspace  */
 701         gfs2_sys_fs_del(sdp);
 702         free_sbd(sdp);
 703 }
 704
 705 /**
 706  * gfs2_sync_fs - sync the filesystem
 707  * @sb: the superblock
 708  *
 709  * Flushes the log to disk.
 710  */
 711
 712 static int gfs2_sync_fs(struct super_block *sb, int wait)
 713 {
 714         struct gfs2_sbd *sdp = sb->s_fs_info;
 715
 716         gfs2_quota_sync(sb, -1);
 717         if (wait)
 718                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 719                                GFS2_LFC_SYNC_FS);
 720         return sdp->sd_log_error;
 721 }
 722
 723 void gfs2_freeze_func(struct work_struct *work)
 724 {
 725         int error;
 726         struct gfs2_holder freeze_gh;
 727         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
 728         struct super_block *sb = sdp->sd_vfs;
 729
 730         atomic_inc(&sb->s_active);
 731         error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 732         if (error) {
 733                 gfs2_assert_withdraw(sdp, 0);
 734         } else {
 735                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 736                 error = thaw_super(sb);
 737                 if (error) {
 738                         fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n",
 739                                 error);
 740                         gfs2_assert_withdraw(sdp, 0);
 741                 }
 742                 gfs2_freeze_unlock(&freeze_gh);
 743         }
 744         deactivate_super(sb);
 745         clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
 746         wake_up_bit(&sdp->sd_flags, SDF_FS_FROZEN);
 747         return;
 748 }
 749
 750 /**
 751  * gfs2_freeze - prevent further writes to the filesystem
 752  * @sb: the VFS structure for the filesystem
 753  *
 754  */
 755
 756 static int gfs2_freeze(struct super_block *sb)
 757 {
 758         struct gfs2_sbd *sdp = sb->s_fs_info;
 759         int error = 0;
 760
 761         mutex_lock(&sdp->sd_freeze_mutex);
 762         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN)
 763                 goto out;
 764
 765         for (;;) {
 766                 if (gfs2_withdrawn(sdp)) {
 767                         error = -EINVAL;
 768                         goto out;
 769                 }
 770
 771                 error = gfs2_lock_fs_check_clean(sdp);
 772                 if (!error)
 773                         break;
 774
 775                 if (error == -EBUSY)
 776                         fs_err(sdp, "waiting for recovery before freeze\n");
 777                 else if (error == -EIO) {
 778                         fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
 779                                "to recovery error.\n");
 780                         goto out;
 781                 } else {
 782                         fs_err(sdp, "error freezing FS: %d\n", error);
 783                 }
 784                 fs_err(sdp, "retrying...\n");
 785                 msleep(1000);
 786         }
 787         set_bit(SDF_FS_FROZEN, &sdp->sd_flags);
 788 out:
 789         mutex_unlock(&sdp->sd_freeze_mutex);
 790         return error;
 791 }
 792
 793 /**
 794  * gfs2_unfreeze - reallow writes to the filesystem
 795  * @sb: the VFS structure for the filesystem
 796  *
 797  */
 798
 799 static int gfs2_unfreeze(struct super_block *sb)
 800 {
 801         struct gfs2_sbd *sdp = sb->s_fs_info;
 802
 803         mutex_lock(&sdp->sd_freeze_mutex);
 804         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
 805             !gfs2_holder_initialized(&sdp->sd_freeze_gh)) {
 806                 mutex_unlock(&sdp->sd_freeze_mutex);
 807                 return 0;
 808         }
 809
 810         gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 811         mutex_unlock(&sdp->sd_freeze_mutex);
 812         return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 813 }
 814
 815 /**
 816  * statfs_fill - fill in the sg for a given RG
 817  * @rgd: the RG
 818  * @sc: the sc structure
 819  *
 820  * Returns: 0 on success, -ESTALE if the LVB is invalid
 821  */
 822
 823 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 824                             struct gfs2_statfs_change_host *sc)
 825 {
 826         gfs2_rgrp_verify(rgd);
 827         sc->sc_total += rgd->rd_data;
 828         sc->sc_free += rgd->rd_free;
 829         sc->sc_dinodes += rgd->rd_dinodes;
 830         return 0;
 831 }
 832
 833 /**
 834  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 835  * @sdp: the filesystem
 836  * @sc: the sc info that will be returned
 837  *
 838  * Any error (other than a signal) will cause this routine to fall back
 839  * to the synchronous version.
 840  *
 841  * FIXME: This really shouldn't busy wait like this.
 842  *
 843  * Returns: errno
 844  */
 845
 846 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 847 {
 848         struct gfs2_rgrpd *rgd_next;
 849         struct gfs2_holder *gha, *gh;
 850         unsigned int slots = 64;
 851         unsigned int x;
 852         int done;
 853         int error = 0, err;
 854
 855         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 856         gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 857         if (!gha)
 858                 return -ENOMEM;
 859         for (x = 0; x < slots; x++)
 860                 gfs2_holder_mark_uninitialized(gha + x);
 861
 862         rgd_next = gfs2_rgrpd_get_first(sdp);
 863
 864         for (;;) {
 865                 done = 1;
 866
 867                 for (x = 0; x < slots; x++) {
 868                         gh = gha + x;
 869
 870                         if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
 871                                 err = gfs2_glock_wait(gh);
 872                                 if (err) {
 873                                         gfs2_holder_uninit(gh);
 874                                         error = err;
 875                                 } else {
 876                                         if (!error) {
 877                                                 struct gfs2_rgrpd *rgd =
 878                                                         gfs2_glock2rgrp(gh->gh_gl);
 879
 880                                                 error = statfs_slow_fill(rgd, sc);
 881                                         }
 882                                         gfs2_glock_dq_uninit(gh);
 883                                 }
 884                         }
 885
 886                         if (gfs2_holder_initialized(gh))
 887                                 done = 0;
 888                         else if (rgd_next && !error) {
 889                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 890                                                            LM_ST_SHARED,
 891                                                            GL_ASYNC,
 892                                                            gh);
 893                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 894                                 done = 0;
 895                         }
 896
 897                         if (signal_pending(current))
 898                                 error = -ERESTARTSYS;
 899                 }
 900
 901                 if (done)
 902                         break;
 903
 904                 yield();
 905         }
 906
 907         kfree(gha);
 908         return error;
 909 }
 910
 911 /**
 912  * gfs2_statfs_i - Do a statfs
 913  * @sdp: the filesystem
 914  * @sg: the sg structure
 915  *
 916  * Returns: errno
 917  */
 918
 919 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 920 {
 921         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 922         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 923
 924         spin_lock(&sdp->sd_statfs_spin);
 925
 926         *sc = *m_sc;
 927         sc->sc_total += l_sc->sc_total;
 928         sc->sc_free += l_sc->sc_free;
 929         sc->sc_dinodes += l_sc->sc_dinodes;
 930
 931         spin_unlock(&sdp->sd_statfs_spin);
 932
 933         if (sc->sc_free < 0)
 934                 sc->sc_free = 0;
 935         if (sc->sc_free > sc->sc_total)
 936                 sc->sc_free = sc->sc_total;
 937         if (sc->sc_dinodes < 0)
 938                 sc->sc_dinodes = 0;
 939
 940         return 0;
 941 }
 942
 943 /**
 944  * gfs2_statfs - Gather and return stats about the filesystem
 945  * @sb: The superblock
 946  * @statfsbuf: The buffer
 947  *
 948  * Returns: 0 on success or error code
 949  */
 950
 951 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 952 {
 953         struct super_block *sb = dentry->d_sb;
 954         struct gfs2_sbd *sdp = sb->s_fs_info;
 955         struct gfs2_statfs_change_host sc;
 956         int error;
 957
 958         error = gfs2_rindex_update(sdp);
 959         if (error)
 960                 return error;
 961
 962         if (gfs2_tune_get(sdp, gt_statfs_slow))
 963                 error = gfs2_statfs_slow(sdp, &sc);
 964         else
 965                 error = gfs2_statfs_i(sdp, &sc);
 966
 967         if (error)
 968                 return error;
 969
 970         buf->f_type = GFS2_MAGIC;
 971         buf->f_bsize = sdp->sd_sb.sb_bsize;
 972         buf->f_blocks = sc.sc_total;
 973         buf->f_bfree = sc.sc_free;
 974         buf->f_bavail = sc.sc_free;
 975         buf->f_files = sc.sc_dinodes + sc.sc_free;
 976         buf->f_ffree = sc.sc_free;
 977         buf->f_namelen = GFS2_FNAMESIZE;
 978
 979         return 0;
 980 }
 981
 982 /**
 983  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 984  * @inode: The inode to drop
 985  *
 986  * If we've received a callback on an iopen lock then it's because a
 987  * remote node tried to deallocate the inode but failed due to this node
 988  * still having the inode open. Here we mark the link count zero
 989  * since we know that it must have reached zero if the GLF_DEMOTE flag
 990  * is set on the iopen glock. If we didn't do a disk read since the
 991  * remote node removed the final link then we might otherwise miss
 992  * this event. This check ensures that this node will deallocate the
 993  * inode's blocks, or alternatively pass the baton on to another
 994  * node for later deallocation.
 995  */
 996
 997 static int gfs2_drop_inode(struct inode *inode)
 998 {
 999         struct gfs2_inode *ip = GFS2_I(inode);
1000
1001         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) &&
1002             inode->i_nlink &&
1003             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1004                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1005                 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
1006                         clear_nlink(inode);
1007         }
1008
1009         /*
1010          * When under memory pressure when an inode's link count has dropped to
1011          * zero, defer deleting the inode to the delete workqueue.  This avoids
1012          * calling into DLM under memory pressure, which can deadlock.
1013          */
1014         if (!inode->i_nlink &&
1015             unlikely(current->flags & PF_MEMALLOC) &&
1016             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1017                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1018
1019                 gfs2_glock_hold(gl);
1020                 if (!gfs2_queue_delete_work(gl, 0))
1021                         gfs2_glock_queue_put(gl);
1022                 return false;
1023         }
1024
1025         return generic_drop_inode(inode);
1026 }
1027
1028 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1029 {
1030         do {
1031                 if (d1 == d2)
1032                         return 1;
1033                 d1 = d1->d_parent;
1034         } while (!IS_ROOT(d1));
1035         return 0;
1036 }
1037
1038 /**
1039  * gfs2_show_options - Show mount options for /proc/mounts
1040  * @s: seq_file structure
1041  * @root: root of this (sub)tree
1042  *
1043  * Returns: 0 on success or error code
1044  */
1045
1046 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1047 {
1048         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1049         struct gfs2_args *args = &sdp->sd_args;
1050         int val;
1051
1052         if (is_ancestor(root, sdp->sd_master_dir))
1053                 seq_puts(s, ",meta");
1054         if (args->ar_lockproto[0])
1055                 seq_show_option(s, "lockproto", args->ar_lockproto);
1056         if (args->ar_locktable[0])
1057                 seq_show_option(s, "locktable", args->ar_locktable);
1058         if (args->ar_hostdata[0])
1059                 seq_show_option(s, "hostdata", args->ar_hostdata);
1060         if (args->ar_spectator)
1061                 seq_puts(s, ",spectator");
1062         if (args->ar_localflocks)
1063                 seq_puts(s, ",localflocks");
1064         if (args->ar_debug)
1065                 seq_puts(s, ",debug");
1066         if (args->ar_posix_acl)
1067                 seq_puts(s, ",acl");
1068         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1069                 char *state;
1070                 switch (args->ar_quota) {
1071                 case GFS2_QUOTA_OFF:
1072                         state = "off";
1073                         break;
1074                 case GFS2_QUOTA_ACCOUNT:
1075                         state = "account";
1076                         break;
1077                 case GFS2_QUOTA_ON:
1078                         state = "on";
1079                         break;
1080                 default:
1081                         state = "unknown";
1082                         break;
1083                 }
1084                 seq_printf(s, ",quota=%s", state);
1085         }
1086         if (args->ar_suiddir)
1087                 seq_puts(s, ",suiddir");
1088         if (args->ar_data != GFS2_DATA_DEFAULT) {
1089                 char *state;
1090                 switch (args->ar_data) {
1091                 case GFS2_DATA_WRITEBACK:
1092                         state = "writeback";
1093                         break;
1094                 case GFS2_DATA_ORDERED:
1095                         state = "ordered";
1096                         break;
1097                 default:
1098                         state = "unknown";
1099                         break;
1100                 }
1101                 seq_printf(s, ",data=%s", state);
1102         }
1103         if (args->ar_discard)
1104                 seq_puts(s, ",discard");
1105         val = sdp->sd_tune.gt_logd_secs;
1106         if (val != 30)
1107                 seq_printf(s, ",commit=%d", val);
1108         val = sdp->sd_tune.gt_statfs_quantum;
1109         if (val != 30)
1110                 seq_printf(s, ",statfs_quantum=%d", val);
1111         else if (sdp->sd_tune.gt_statfs_slow)
1112                 seq_puts(s, ",statfs_quantum=0");
1113         val = sdp->sd_tune.gt_quota_quantum;
1114         if (val != 60)
1115                 seq_printf(s, ",quota_quantum=%d", val);
1116         if (args->ar_statfs_percent)
1117                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1118         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1119                 const char *state;
1120
1121                 switch (args->ar_errors) {
1122                 case GFS2_ERRORS_WITHDRAW:
1123                         state = "withdraw";
1124                         break;
1125                 case GFS2_ERRORS_PANIC:
1126                         state = "panic";
1127                         break;
1128                 default:
1129                         state = "unknown";
1130                         break;
1131                 }
1132                 seq_printf(s, ",errors=%s", state);
1133         }
1134         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1135                 seq_puts(s, ",nobarrier");
1136         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1137                 seq_puts(s, ",demote_interface_used");
1138         if (args->ar_rgrplvb)
1139                 seq_puts(s, ",rgrplvb");
1140         if (args->ar_loccookie)
1141                 seq_puts(s, ",loccookie");
1142         return 0;
1143 }
1144
1145 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1146 {
1147         struct inode *inode = &ip->i_inode;
1148         struct gfs2_glock *gl = ip->i_gl;
1149
1150         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1151         truncate_inode_pages(&inode->i_data, 0);
1152
1153         if (atomic_read(&gl->gl_revokes) == 0) {
1154                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1155                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1156         }
1157 }
1158
1159 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1160 {
1161         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1162         struct gfs2_rgrpd *rgd;
1163         struct gfs2_holder gh;
1164         int error;
1165
1166         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1167                 gfs2_consist_inode(ip);
1168                 return -EIO;
1169         }
1170
1171         error = gfs2_rindex_update(sdp);
1172         if (error)
1173                 return error;
1174
1175         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1176         if (error)
1177                 return error;
1178
1179         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1180         if (!rgd) {
1181                 gfs2_consist_inode(ip);
1182                 error = -EIO;
1183                 goto out_qs;
1184         }
1185
1186         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1187                                    LM_FLAG_NODE_SCOPE, &gh);
1188         if (error)
1189                 goto out_qs;
1190
1191         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1192                                  sdp->sd_jdesc->jd_blocks);
1193         if (error)
1194                 goto out_rg_gunlock;
1195
1196         gfs2_free_di(rgd, ip);
1197
1198         gfs2_final_release_pages(ip);
1199
1200         gfs2_trans_end(sdp);
1201
1202 out_rg_gunlock:
1203         gfs2_glock_dq_uninit(&gh);
1204 out_qs:
1205         gfs2_quota_unhold(ip);
1206         return error;
1207 }
1208
1209 /**
1210  * gfs2_glock_put_eventually
1211  * @gl: The glock to put
1212  *
1213  * When under memory pressure, trigger a deferred glock put to make sure we
1214  * won't call into DLM and deadlock.  Otherwise, put the glock directly.
1215  */
1216
1217 static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
1218 {
1219         if (current->flags & PF_MEMALLOC)
1220                 gfs2_glock_queue_put(gl);
1221         else
1222                 gfs2_glock_put(gl);
1223 }
1224
1225 static bool gfs2_upgrade_iopen_glock(struct inode *inode)
1226 {
1227         struct gfs2_inode *ip = GFS2_I(inode);
1228         struct gfs2_sbd *sdp = GFS2_SB(inode);
1229         struct gfs2_holder *gh = &ip->i_iopen_gh;
1230         long timeout = 5 * HZ;
1231         int error;
1232
1233         gh->gh_flags |= GL_NOCACHE;
1234         gfs2_glock_dq_wait(gh);
1235
1236         /*
1237          * If there are no other lock holders, we'll get the lock immediately.
1238          * Otherwise, the other nodes holding the lock will be notified about
1239          * our locking request.  If they don't have the inode open, they'll
1240          * evict the cached inode and release the lock.  Otherwise, if they
1241          * poke the inode glock, we'll take this as an indication that they
1242          * still need the iopen glock and that they'll take care of deleting
1243          * the inode when they're done.  As a last resort, if another node
1244          * keeps holding the iopen glock without showing any activity on the
1245          * inode glock, we'll eventually time out.
1246          *
1247          * Note that we're passing the LM_FLAG_TRY_1CB flag to the first
1248          * locking request as an optimization to notify lock holders as soon as
1249          * possible.  Without that flag, they'd be notified implicitly by the
1250          * second locking request.
1251          */
1252
1253         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, gh);
1254         error = gfs2_glock_nq(gh);
1255         if (error != GLR_TRYFAILED)
1256                 return !error;
1257
1258         gfs2_holder_reinit(LM_ST_EXCLUSIVE, GL_ASYNC | GL_NOCACHE, gh);
1259         error = gfs2_glock_nq(gh);
1260         if (error)
1261                 return false;
1262
1263         timeout = wait_event_interruptible_timeout(sdp->sd_async_glock_wait,
1264                 !test_bit(HIF_WAIT, &gh->gh_iflags) ||
1265                 test_bit(GLF_DEMOTE, &ip->i_gl->gl_flags),
1266                 timeout);
1267         if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) {
1268                 gfs2_glock_dq(gh);
1269                 return false;
1270         }
1271         return true;
1272 }
1273
1274 /**
1275  * evict_should_delete - determine whether the inode is eligible for deletion
1276  * @inode: The inode to evict
1277  *
1278  * This function determines whether the evicted inode is eligible to be deleted
1279  * and locks the inode glock.
1280  *
1281  * Returns: the fate of the dinode
1282  */
1283 static enum dinode_demise evict_should_delete(struct inode *inode,
1284                                               struct gfs2_holder *gh)
1285 {
1286         struct gfs2_inode *ip = GFS2_I(inode);
1287         struct super_block *sb = inode->i_sb;
1288         struct gfs2_sbd *sdp = sb->s_fs_info;
1289         int ret;
1290
1291         if (test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1292                 BUG_ON(!gfs2_glock_is_locked_by_me(ip->i_gl));
1293                 goto should_delete;
1294         }
1295
1296         if (test_bit(GIF_DEFERRED_DELETE, &ip->i_flags))
1297                 return SHOULD_DEFER_EVICTION;
1298
1299         /* Deletes should never happen under memory pressure anymore.  */
1300         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
1301                 return SHOULD_DEFER_EVICTION;
1302
1303         /* Must not read inode block until block type has been verified */
1304         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, gh);
1305         if (unlikely(ret)) {
1306                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1307                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1308                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1309                 return SHOULD_DEFER_EVICTION;
1310         }
1311
1312         if (gfs2_inode_already_deleted(ip->i_gl, ip->i_no_formal_ino))
1313                 return SHOULD_NOT_DELETE_DINODE;
1314         ret = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1315         if (ret)
1316                 return SHOULD_NOT_DELETE_DINODE;
1317
1318         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1319                 ret = gfs2_inode_refresh(ip);
1320                 if (ret)
1321                         return SHOULD_NOT_DELETE_DINODE;
1322         }
1323
1324         /*
1325          * The inode may have been recreated in the meantime.
1326          */
1327         if (inode->i_nlink)
1328                 return SHOULD_NOT_DELETE_DINODE;
1329
1330 should_delete:
1331         if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
1332             test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1333                 if (!gfs2_upgrade_iopen_glock(inode)) {
1334                         gfs2_holder_uninit(&ip->i_iopen_gh);
1335                         return SHOULD_NOT_DELETE_DINODE;
1336                 }
1337         }
1338         return SHOULD_DELETE_DINODE;
1339 }
1340
1341 /**
1342  * evict_unlinked_inode - delete the pieces of an unlinked evicted inode
1343  * @inode: The inode to evict
1344  */
1345 static int evict_unlinked_inode(struct inode *inode)
1346 {
1347         struct gfs2_inode *ip = GFS2_I(inode);
1348         int ret;
1349
1350         if (S_ISDIR(inode->i_mode) &&
1351             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1352                 ret = gfs2_dir_exhash_dealloc(ip);
1353                 if (ret)
1354                         goto out;
1355         }
1356
1357         if (ip->i_eattr) {
1358                 ret = gfs2_ea_dealloc(ip);
1359                 if (ret)
1360                         goto out;
1361         }
1362
1363         if (!gfs2_is_stuffed(ip)) {
1364                 ret = gfs2_file_dealloc(ip);
1365                 if (ret)
1366                         goto out;
1367         }
1368
1369         /* We're about to clear the bitmap for the dinode, but as soon as we
1370            do, gfs2_create_inode can create another inode at the same block
1371            location and try to set gl_object again. We clear gl_object here so
1372            that subsequent inode creates don't see an old gl_object. */
1373         glock_clear_object(ip->i_gl, ip);
1374         ret = gfs2_dinode_dealloc(ip);
1375         gfs2_inode_remember_delete(ip->i_gl, ip->i_no_formal_ino);
1376 out:
1377         return ret;
1378 }
1379
1380 /*
1381  * evict_linked_inode - evict an inode whose dinode has not been unlinked
1382  * @inode: The inode to evict
1383  */
1384 static int evict_linked_inode(struct inode *inode)
1385 {
1386         struct super_block *sb = inode->i_sb;
1387         struct gfs2_sbd *sdp = sb->s_fs_info;
1388         struct gfs2_inode *ip = GFS2_I(inode);
1389         struct address_space *metamapping;
1390         int ret;
1391
1392         gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
1393                        GFS2_LFC_EVICT_INODE);
1394         metamapping = gfs2_glock2aspace(ip->i_gl);
1395         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1396                 filemap_fdatawrite(metamapping);
1397                 filemap_fdatawait(metamapping);
1398         }
1399         write_inode_now(inode, 1);
1400         gfs2_ail_flush(ip->i_gl, 0);
1401
1402         ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1403         if (ret)
1404                 return ret;
1405
1406         /* Needs to be done before glock release & also in a transaction */
1407         truncate_inode_pages(&inode->i_data, 0);
1408         truncate_inode_pages(metamapping, 0);
1409         gfs2_trans_end(sdp);
1410         return 0;
1411 }
1412
1413 /**
1414  * gfs2_evict_inode - Remove an inode from cache
1415  * @inode: The inode to evict
1416  *
1417  * There are three cases to consider:
1418  * 1. i_nlink == 0, we are final opener (and must deallocate)
1419  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1420  * 3. i_nlink > 0
1421  *
1422  * If the fs is read only, then we have to treat all cases as per #3
1423  * since we are unable to do any deallocation. The inode will be
1424  * deallocated by the next read/write node to attempt an allocation
1425  * in the same resource group
1426  *
1427  * We have to (at the moment) hold the inodes main lock to cover
1428  * the gap between unlocking the shared lock on the iopen lock and
1429  * taking the exclusive lock. I'd rather do a shared -> exclusive
1430  * conversion on the iopen lock, but we can change that later. This
1431  * is safe, just less efficient.
1432  */
1433
1434 static void gfs2_evict_inode(struct inode *inode)
1435 {
1436         struct super_block *sb = inode->i_sb;
1437         struct gfs2_sbd *sdp = sb->s_fs_info;
1438         struct gfs2_inode *ip = GFS2_I(inode);
1439         struct gfs2_holder gh;
1440         int ret;
1441
1442         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1443                 clear_inode(inode);
1444                 return;
1445         }
1446
1447         if (inode->i_nlink || sb_rdonly(sb))
1448                 goto out;
1449
1450         gfs2_holder_mark_uninitialized(&gh);
1451         ret = evict_should_delete(inode, &gh);
1452         if (ret == SHOULD_DEFER_EVICTION)
1453                 goto out;
1454         if (ret == SHOULD_DELETE_DINODE)
1455                 ret = evict_unlinked_inode(inode);
1456         else
1457                 ret = evict_linked_inode(inode);
1458
1459         if (gfs2_rs_active(&ip->i_res))
1460                 gfs2_rs_deltree(&ip->i_res);
1461
1462         if (gfs2_holder_initialized(&gh)) {
1463                 glock_clear_object(ip->i_gl, ip);
1464                 gfs2_glock_dq_uninit(&gh);
1465         }
1466         if (ret && ret != GLR_TRYFAILED && ret != -EROFS)
1467                 fs_warn(sdp, "gfs2_evict_inode: %d\n", ret);
1468 out:
1469         truncate_inode_pages_final(&inode->i_data);
1470         if (ip->i_qadata)
1471                 gfs2_assert_warn(sdp, ip->i_qadata->qa_ref == 0);
1472         gfs2_rs_delete(ip, NULL);
1473         gfs2_ordered_del_inode(ip);
1474         clear_inode(inode);
1475         gfs2_dir_hash_inval(ip);
1476         if (ip->i_gl) {
1477                 glock_clear_object(ip->i_gl, ip);
1478                 wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
1479                 gfs2_glock_add_to_lru(ip->i_gl);
1480                 gfs2_glock_put_eventually(ip->i_gl);
1481                 ip->i_gl = NULL;
1482         }
1483         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1484                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1485
1486                 glock_clear_object(gl, ip);
1487                 if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1488                         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1489                         gfs2_glock_dq(&ip->i_iopen_gh);
1490                 }
1491                 gfs2_glock_hold(gl);
1492                 gfs2_holder_uninit(&ip->i_iopen_gh);
1493                 gfs2_glock_put_eventually(gl);
1494         }
1495 }
1496
1497 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1498 {
1499         struct gfs2_inode *ip;
1500
1501         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1502         if (!ip)
1503                 return NULL;
1504         ip->i_flags = 0;
1505         ip->i_gl = NULL;
1506         gfs2_holder_mark_uninitialized(&ip->i_iopen_gh);
1507         memset(&ip->i_res, 0, sizeof(ip->i_res));
1508         RB_CLEAR_NODE(&ip->i_res.rs_node);
1509         ip->i_rahead = 0;
1510         return &ip->i_inode;
1511 }
1512
1513 static void gfs2_free_inode(struct inode *inode)
1514 {
1515         kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
1516 }
1517
1518 extern void free_local_statfs_inodes(struct gfs2_sbd *sdp)
1519 {
1520         struct local_statfs_inode *lsi, *safe;
1521
1522         /* Run through the statfs inodes list to iput and free memory */
1523         list_for_each_entry_safe(lsi, safe, &sdp->sd_sc_inodes_list, si_list) {
1524                 if (lsi->si_jid == sdp->sd_jdesc->jd_jid)
1525                         sdp->sd_sc_inode = NULL; /* belongs to this node */
1526                 if (lsi->si_sc_inode)
1527                         iput(lsi->si_sc_inode);
1528                 list_del(&lsi->si_list);
1529                 kfree(lsi);
1530         }
1531 }
1532
1533 extern struct inode *find_local_statfs_inode(struct gfs2_sbd *sdp,
1534                                              unsigned int index)
1535 {
1536         struct local_statfs_inode *lsi;
1537
1538         /* Return the local (per node) statfs inode in the
1539          * sdp->sd_sc_inodes_list corresponding to the 'index'. */
1540         list_for_each_entry(lsi, &sdp->sd_sc_inodes_list, si_list) {
1541                 if (lsi->si_jid == index)
1542                         return lsi->si_sc_inode;
1543         }
1544         return NULL;
1545 }
1546
1547 const struct super_operations gfs2_super_ops = {
1548         .alloc_inode            = gfs2_alloc_inode,
1549         .free_inode             = gfs2_free_inode,
1550         .write_inode            = gfs2_write_inode,
1551         .dirty_inode            = gfs2_dirty_inode,
1552         .evict_inode            = gfs2_evict_inode,
1553         .put_super              = gfs2_put_super,
1554         .sync_fs                = gfs2_sync_fs,
1555         .freeze_super           = gfs2_freeze,
1556         .thaw_super             = gfs2_unfreeze,
1557         .statfs                 = gfs2_statfs,
1558         .drop_inode             = gfs2_drop_inode,
1559         .show_options           = gfs2_show_options,
1560 };
1561