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 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  *
 703  * Flushes the log to disk.
 704  */
 705
 706 static int gfs2_sync_fs(struct super_block *sb, int wait)
 707 {
 708         struct gfs2_sbd *sdp = sb->s_fs_info;
 709
 710         gfs2_quota_sync(sb, -1);
 711         if (wait)
 712                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 713                                GFS2_LFC_SYNC_FS);
 714         return sdp->sd_log_error;
 715 }
 716
 717 void gfs2_freeze_func(struct work_struct *work)
 718 {
 719         int error;
 720         struct gfs2_holder freeze_gh;
 721         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
 722         struct super_block *sb = sdp->sd_vfs;
 723
 724         atomic_inc(&sb->s_active);
 725         error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 726         if (error) {
 727                 gfs2_assert_withdraw(sdp, 0);
 728         } else {
 729                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 730                 error = thaw_super(sb);
 731                 if (error) {
 732                         fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n",
 733                                 error);
 734                         gfs2_assert_withdraw(sdp, 0);
 735                 }
 736                 gfs2_freeze_unlock(&freeze_gh);
 737         }
 738         deactivate_super(sb);
 739         clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
 740         wake_up_bit(&sdp->sd_flags, SDF_FS_FROZEN);
 741         return;
 742 }
 743
 744 /**
 745  * gfs2_freeze - prevent further writes to the filesystem
 746  * @sb: the VFS structure for the filesystem
 747  *
 748  */
 749
 750 static int gfs2_freeze(struct super_block *sb)
 751 {
 752         struct gfs2_sbd *sdp = sb->s_fs_info;
 753         int error = 0;
 754
 755         mutex_lock(&sdp->sd_freeze_mutex);
 756         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN)
 757                 goto out;
 758
 759         for (;;) {
 760                 if (gfs2_withdrawn(sdp)) {
 761                         error = -EINVAL;
 762                         goto out;
 763                 }
 764
 765                 error = gfs2_lock_fs_check_clean(sdp);
 766                 if (!error)
 767                         break;
 768
 769                 if (error == -EBUSY)
 770                         fs_err(sdp, "waiting for recovery before freeze\n");
 771                 else if (error == -EIO) {
 772                         fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
 773                                "to recovery error.\n");
 774                         goto out;
 775                 } else {
 776                         fs_err(sdp, "error freezing FS: %d\n", error);
 777                 }
 778                 fs_err(sdp, "retrying...\n");
 779                 msleep(1000);
 780         }
 781         set_bit(SDF_FS_FROZEN, &sdp->sd_flags);
 782 out:
 783         mutex_unlock(&sdp->sd_freeze_mutex);
 784         return error;
 785 }
 786
 787 /**
 788  * gfs2_unfreeze - reallow writes to the filesystem
 789  * @sb: the VFS structure for the filesystem
 790  *
 791  */
 792
 793 static int gfs2_unfreeze(struct super_block *sb)
 794 {
 795         struct gfs2_sbd *sdp = sb->s_fs_info;
 796
 797         mutex_lock(&sdp->sd_freeze_mutex);
 798         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
 799             !gfs2_holder_initialized(&sdp->sd_freeze_gh)) {
 800                 mutex_unlock(&sdp->sd_freeze_mutex);
 801                 return 0;
 802         }
 803
 804         gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 805         mutex_unlock(&sdp->sd_freeze_mutex);
 806         return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 807 }
 808
 809 /**
 810  * statfs_fill - fill in the sg for a given RG
 811  * @rgd: the RG
 812  * @sc: the sc structure
 813  *
 814  * Returns: 0 on success, -ESTALE if the LVB is invalid
 815  */
 816
 817 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 818                             struct gfs2_statfs_change_host *sc)
 819 {
 820         gfs2_rgrp_verify(rgd);
 821         sc->sc_total += rgd->rd_data;
 822         sc->sc_free += rgd->rd_free;
 823         sc->sc_dinodes += rgd->rd_dinodes;
 824         return 0;
 825 }
 826
 827 /**
 828  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 829  * @sdp: the filesystem
 830  * @sc: the sc info that will be returned
 831  *
 832  * Any error (other than a signal) will cause this routine to fall back
 833  * to the synchronous version.
 834  *
 835  * FIXME: This really shouldn't busy wait like this.
 836  *
 837  * Returns: errno
 838  */
 839
 840 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 841 {
 842         struct gfs2_rgrpd *rgd_next;
 843         struct gfs2_holder *gha, *gh;
 844         unsigned int slots = 64;
 845         unsigned int x;
 846         int done;
 847         int error = 0, err;
 848
 849         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 850         gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 851         if (!gha)
 852                 return -ENOMEM;
 853         for (x = 0; x < slots; x++)
 854                 gfs2_holder_mark_uninitialized(gha + x);
 855
 856         rgd_next = gfs2_rgrpd_get_first(sdp);
 857
 858         for (;;) {
 859                 done = 1;
 860
 861                 for (x = 0; x < slots; x++) {
 862                         gh = gha + x;
 863
 864                         if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
 865                                 err = gfs2_glock_wait(gh);
 866                                 if (err) {
 867                                         gfs2_holder_uninit(gh);
 868                                         error = err;
 869                                 } else {
 870                                         if (!error) {
 871                                                 struct gfs2_rgrpd *rgd =
 872                                                         gfs2_glock2rgrp(gh->gh_gl);
 873
 874                                                 error = statfs_slow_fill(rgd, sc);
 875                                         }
 876                                         gfs2_glock_dq_uninit(gh);
 877                                 }
 878                         }
 879
 880                         if (gfs2_holder_initialized(gh))
 881                                 done = 0;
 882                         else if (rgd_next && !error) {
 883                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 884                                                            LM_ST_SHARED,
 885                                                            GL_ASYNC,
 886                                                            gh);
 887                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 888                                 done = 0;
 889                         }
 890
 891                         if (signal_pending(current))
 892                                 error = -ERESTARTSYS;
 893                 }
 894
 895                 if (done)
 896                         break;
 897
 898                 yield();
 899         }
 900
 901         kfree(gha);
 902         return error;
 903 }
 904
 905 /**
 906  * gfs2_statfs_i - Do a statfs
 907  * @sdp: the filesystem
 908  * @sg: the sg structure
 909  *
 910  * Returns: errno
 911  */
 912
 913 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 914 {
 915         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 916         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 917
 918         spin_lock(&sdp->sd_statfs_spin);
 919
 920         *sc = *m_sc;
 921         sc->sc_total += l_sc->sc_total;
 922         sc->sc_free += l_sc->sc_free;
 923         sc->sc_dinodes += l_sc->sc_dinodes;
 924
 925         spin_unlock(&sdp->sd_statfs_spin);
 926
 927         if (sc->sc_free < 0)
 928                 sc->sc_free = 0;
 929         if (sc->sc_free > sc->sc_total)
 930                 sc->sc_free = sc->sc_total;
 931         if (sc->sc_dinodes < 0)
 932                 sc->sc_dinodes = 0;
 933
 934         return 0;
 935 }
 936
 937 /**
 938  * gfs2_statfs - Gather and return stats about the filesystem
 939  * @sb: The superblock
 940  * @statfsbuf: The buffer
 941  *
 942  * Returns: 0 on success or error code
 943  */
 944
 945 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 946 {
 947         struct super_block *sb = dentry->d_sb;
 948         struct gfs2_sbd *sdp = sb->s_fs_info;
 949         struct gfs2_statfs_change_host sc;
 950         int error;
 951
 952         error = gfs2_rindex_update(sdp);
 953         if (error)
 954                 return error;
 955
 956         if (gfs2_tune_get(sdp, gt_statfs_slow))
 957                 error = gfs2_statfs_slow(sdp, &sc);
 958         else
 959                 error = gfs2_statfs_i(sdp, &sc);
 960
 961         if (error)
 962                 return error;
 963
 964         buf->f_type = GFS2_MAGIC;
 965         buf->f_bsize = sdp->sd_sb.sb_bsize;
 966         buf->f_blocks = sc.sc_total;
 967         buf->f_bfree = sc.sc_free;
 968         buf->f_bavail = sc.sc_free;
 969         buf->f_files = sc.sc_dinodes + sc.sc_free;
 970         buf->f_ffree = sc.sc_free;
 971         buf->f_namelen = GFS2_FNAMESIZE;
 972
 973         return 0;
 974 }
 975
 976 /**
 977  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 978  * @inode: The inode to drop
 979  *
 980  * If we've received a callback on an iopen lock then it's because a
 981  * remote node tried to deallocate the inode but failed due to this node
 982  * still having the inode open. Here we mark the link count zero
 983  * since we know that it must have reached zero if the GLF_DEMOTE flag
 984  * is set on the iopen glock. If we didn't do a disk read since the
 985  * remote node removed the final link then we might otherwise miss
 986  * this event. This check ensures that this node will deallocate the
 987  * inode's blocks, or alternatively pass the baton on to another
 988  * node for later deallocation.
 989  */
 990
 991 static int gfs2_drop_inode(struct inode *inode)
 992 {
 993         struct gfs2_inode *ip = GFS2_I(inode);
 994
 995         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) &&
 996             inode->i_nlink &&
 997             gfs2_holder_initialized(&ip->i_iopen_gh)) {
 998                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 999                 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
1000                         clear_nlink(inode);
1001         }
1002
1003         /*
1004          * When under memory pressure when an inode's link count has dropped to
1005          * zero, defer deleting the inode to the delete workqueue.  This avoids
1006          * calling into DLM under memory pressure, which can deadlock.
1007          */
1008         if (!inode->i_nlink &&
1009             unlikely(current->flags & PF_MEMALLOC) &&
1010             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1011                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1012
1013                 gfs2_glock_hold(gl);
1014                 if (!gfs2_queue_delete_work(gl, 0))
1015                         gfs2_glock_queue_put(gl);
1016                 return false;
1017         }
1018
1019         return generic_drop_inode(inode);
1020 }
1021
1022 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1023 {
1024         do {
1025                 if (d1 == d2)
1026                         return 1;
1027                 d1 = d1->d_parent;
1028         } while (!IS_ROOT(d1));
1029         return 0;
1030 }
1031
1032 /**
1033  * gfs2_show_options - Show mount options for /proc/mounts
1034  * @s: seq_file structure
1035  * @root: root of this (sub)tree
1036  *
1037  * Returns: 0 on success or error code
1038  */
1039
1040 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1041 {
1042         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1043         struct gfs2_args *args = &sdp->sd_args;
1044         int val;
1045
1046         if (is_ancestor(root, sdp->sd_master_dir))
1047                 seq_puts(s, ",meta");
1048         if (args->ar_lockproto[0])
1049                 seq_show_option(s, "lockproto", args->ar_lockproto);
1050         if (args->ar_locktable[0])
1051                 seq_show_option(s, "locktable", args->ar_locktable);
1052         if (args->ar_hostdata[0])
1053                 seq_show_option(s, "hostdata", args->ar_hostdata);
1054         if (args->ar_spectator)
1055                 seq_puts(s, ",spectator");
1056         if (args->ar_localflocks)
1057                 seq_puts(s, ",localflocks");
1058         if (args->ar_debug)
1059                 seq_puts(s, ",debug");
1060         if (args->ar_posix_acl)
1061                 seq_puts(s, ",acl");
1062         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1063                 char *state;
1064                 switch (args->ar_quota) {
1065                 case GFS2_QUOTA_OFF:
1066                         state = "off";
1067                         break;
1068                 case GFS2_QUOTA_ACCOUNT:
1069                         state = "account";
1070                         break;
1071                 case GFS2_QUOTA_ON:
1072                         state = "on";
1073                         break;
1074                 default:
1075                         state = "unknown";
1076                         break;
1077                 }
1078                 seq_printf(s, ",quota=%s", state);
1079         }
1080         if (args->ar_suiddir)
1081                 seq_puts(s, ",suiddir");
1082         if (args->ar_data != GFS2_DATA_DEFAULT) {
1083                 char *state;
1084                 switch (args->ar_data) {
1085                 case GFS2_DATA_WRITEBACK:
1086                         state = "writeback";
1087                         break;
1088                 case GFS2_DATA_ORDERED:
1089                         state = "ordered";
1090                         break;
1091                 default:
1092                         state = "unknown";
1093                         break;
1094                 }
1095                 seq_printf(s, ",data=%s", state);
1096         }
1097         if (args->ar_discard)
1098                 seq_puts(s, ",discard");
1099         val = sdp->sd_tune.gt_logd_secs;
1100         if (val != 30)
1101                 seq_printf(s, ",commit=%d", val);
1102         val = sdp->sd_tune.gt_statfs_quantum;
1103         if (val != 30)
1104                 seq_printf(s, ",statfs_quantum=%d", val);
1105         else if (sdp->sd_tune.gt_statfs_slow)
1106                 seq_puts(s, ",statfs_quantum=0");
1107         val = sdp->sd_tune.gt_quota_quantum;
1108         if (val != 60)
1109                 seq_printf(s, ",quota_quantum=%d", val);
1110         if (args->ar_statfs_percent)
1111                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1112         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1113                 const char *state;
1114
1115                 switch (args->ar_errors) {
1116                 case GFS2_ERRORS_WITHDRAW:
1117                         state = "withdraw";
1118                         break;
1119                 case GFS2_ERRORS_PANIC:
1120                         state = "panic";
1121                         break;
1122                 default:
1123                         state = "unknown";
1124                         break;
1125                 }
1126                 seq_printf(s, ",errors=%s", state);
1127         }
1128         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1129                 seq_puts(s, ",nobarrier");
1130         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1131                 seq_puts(s, ",demote_interface_used");
1132         if (args->ar_rgrplvb)
1133                 seq_puts(s, ",rgrplvb");
1134         if (args->ar_loccookie)
1135                 seq_puts(s, ",loccookie");
1136         return 0;
1137 }
1138
1139 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1140 {
1141         struct inode *inode = &ip->i_inode;
1142         struct gfs2_glock *gl = ip->i_gl;
1143
1144         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1145         truncate_inode_pages(&inode->i_data, 0);
1146
1147         if (atomic_read(&gl->gl_revokes) == 0) {
1148                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1149                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1150         }
1151 }
1152
1153 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1154 {
1155         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1156         struct gfs2_rgrpd *rgd;
1157         struct gfs2_holder gh;
1158         int error;
1159
1160         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1161                 gfs2_consist_inode(ip);
1162                 return -EIO;
1163         }
1164
1165         error = gfs2_rindex_update(sdp);
1166         if (error)
1167                 return error;
1168
1169         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1170         if (error)
1171                 return error;
1172
1173         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1174         if (!rgd) {
1175                 gfs2_consist_inode(ip);
1176                 error = -EIO;
1177                 goto out_qs;
1178         }
1179
1180         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1181                                    LM_FLAG_NODE_SCOPE, &gh);
1182         if (error)
1183                 goto out_qs;
1184
1185         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1186                                  sdp->sd_jdesc->jd_blocks);
1187         if (error)
1188                 goto out_rg_gunlock;
1189
1190         gfs2_free_di(rgd, ip);
1191
1192         gfs2_final_release_pages(ip);
1193
1194         gfs2_trans_end(sdp);
1195
1196 out_rg_gunlock:
1197         gfs2_glock_dq_uninit(&gh);
1198 out_qs:
1199         gfs2_quota_unhold(ip);
1200         return error;
1201 }
1202
1203 /**
1204  * gfs2_glock_put_eventually
1205  * @gl: The glock to put
1206  *
1207  * When under memory pressure, trigger a deferred glock put to make sure we
1208  * won't call into DLM and deadlock.  Otherwise, put the glock directly.
1209  */
1210
1211 static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
1212 {
1213         if (current->flags & PF_MEMALLOC)
1214                 gfs2_glock_queue_put(gl);
1215         else
1216                 gfs2_glock_put(gl);
1217 }
1218
1219 static bool gfs2_upgrade_iopen_glock(struct inode *inode)
1220 {
1221         struct gfs2_inode *ip = GFS2_I(inode);
1222         struct gfs2_sbd *sdp = GFS2_SB(inode);
1223         struct gfs2_holder *gh = &ip->i_iopen_gh;
1224         long timeout = 5 * HZ;
1225         int error;
1226
1227         gh->gh_flags |= GL_NOCACHE;
1228         gfs2_glock_dq_wait(gh);
1229
1230         /*
1231          * If there are no other lock holders, we'll get the lock immediately.
1232          * Otherwise, the other nodes holding the lock will be notified about
1233          * our locking request.  If they don't have the inode open, they'll
1234          * evict the cached inode and release the lock.  Otherwise, if they
1235          * poke the inode glock, we'll take this as an indication that they
1236          * still need the iopen glock and that they'll take care of deleting
1237          * the inode when they're done.  As a last resort, if another node
1238          * keeps holding the iopen glock without showing any activity on the
1239          * inode glock, we'll eventually time out.
1240          *
1241          * Note that we're passing the LM_FLAG_TRY_1CB flag to the first
1242          * locking request as an optimization to notify lock holders as soon as
1243          * possible.  Without that flag, they'd be notified implicitly by the
1244          * second locking request.
1245          */
1246
1247         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, gh);
1248         error = gfs2_glock_nq(gh);
1249         if (error != GLR_TRYFAILED)
1250                 return !error;
1251
1252         gfs2_holder_reinit(LM_ST_EXCLUSIVE, GL_ASYNC | GL_NOCACHE, gh);
1253         error = gfs2_glock_nq(gh);
1254         if (error)
1255                 return false;
1256
1257         timeout = wait_event_interruptible_timeout(sdp->sd_async_glock_wait,
1258                 !test_bit(HIF_WAIT, &gh->gh_iflags) ||
1259                 test_bit(GLF_DEMOTE, &ip->i_gl->gl_flags),
1260                 timeout);
1261         if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) {
1262                 gfs2_glock_dq(gh);
1263                 return false;
1264         }
1265         return true;
1266 }
1267
1268 /**
1269  * evict_should_delete - determine whether the inode is eligible for deletion
1270  * @inode: The inode to evict
1271  *
1272  * This function determines whether the evicted inode is eligible to be deleted
1273  * and locks the inode glock.
1274  *
1275  * Returns: the fate of the dinode
1276  */
1277 static enum dinode_demise evict_should_delete(struct inode *inode,
1278                                               struct gfs2_holder *gh)
1279 {
1280         struct gfs2_inode *ip = GFS2_I(inode);
1281         struct super_block *sb = inode->i_sb;
1282         struct gfs2_sbd *sdp = sb->s_fs_info;
1283         int ret;
1284
1285         if (test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1286                 BUG_ON(!gfs2_glock_is_locked_by_me(ip->i_gl));
1287                 goto should_delete;
1288         }
1289
1290         if (test_bit(GIF_DEFERRED_DELETE, &ip->i_flags))
1291                 return SHOULD_DEFER_EVICTION;
1292
1293         /* Deletes should never happen under memory pressure anymore.  */
1294         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
1295                 return SHOULD_DEFER_EVICTION;
1296
1297         /* Must not read inode block until block type has been verified */
1298         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, gh);
1299         if (unlikely(ret)) {
1300                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1301                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1302                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1303                 return SHOULD_DEFER_EVICTION;
1304         }
1305
1306         if (gfs2_inode_already_deleted(ip->i_gl, ip->i_no_formal_ino))
1307                 return SHOULD_NOT_DELETE_DINODE;
1308         ret = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1309         if (ret)
1310                 return SHOULD_NOT_DELETE_DINODE;
1311
1312         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1313                 ret = gfs2_inode_refresh(ip);
1314                 if (ret)
1315                         return SHOULD_NOT_DELETE_DINODE;
1316         }
1317
1318         /*
1319          * The inode may have been recreated in the meantime.
1320          */
1321         if (inode->i_nlink)
1322                 return SHOULD_NOT_DELETE_DINODE;
1323
1324 should_delete:
1325         if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
1326             test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1327                 if (!gfs2_upgrade_iopen_glock(inode)) {
1328                         gfs2_holder_uninit(&ip->i_iopen_gh);
1329                         return SHOULD_NOT_DELETE_DINODE;
1330                 }
1331         }
1332         return SHOULD_DELETE_DINODE;
1333 }
1334
1335 /**
1336  * evict_unlinked_inode - delete the pieces of an unlinked evicted inode
1337  * @inode: The inode to evict
1338  */
1339 static int evict_unlinked_inode(struct inode *inode)
1340 {
1341         struct gfs2_inode *ip = GFS2_I(inode);
1342         int ret;
1343
1344         if (S_ISDIR(inode->i_mode) &&
1345             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1346                 ret = gfs2_dir_exhash_dealloc(ip);
1347                 if (ret)
1348                         goto out;
1349         }
1350
1351         if (ip->i_eattr) {
1352                 ret = gfs2_ea_dealloc(ip);
1353                 if (ret)
1354                         goto out;
1355         }
1356
1357         if (!gfs2_is_stuffed(ip)) {
1358                 ret = gfs2_file_dealloc(ip);
1359                 if (ret)
1360                         goto out;
1361         }
1362
1363         /* We're about to clear the bitmap for the dinode, but as soon as we
1364            do, gfs2_create_inode can create another inode at the same block
1365            location and try to set gl_object again. We clear gl_object here so
1366            that subsequent inode creates don't see an old gl_object. */
1367         glock_clear_object(ip->i_gl, ip);
1368         ret = gfs2_dinode_dealloc(ip);
1369         gfs2_inode_remember_delete(ip->i_gl, ip->i_no_formal_ino);
1370 out:
1371         return ret;
1372 }
1373
1374 /*
1375  * evict_linked_inode - evict an inode whose dinode has not been unlinked
1376  * @inode: The inode to evict
1377  */
1378 static int evict_linked_inode(struct inode *inode)
1379 {
1380         struct super_block *sb = inode->i_sb;
1381         struct gfs2_sbd *sdp = sb->s_fs_info;
1382         struct gfs2_inode *ip = GFS2_I(inode);
1383         struct address_space *metamapping;
1384         int ret;
1385
1386         gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
1387                        GFS2_LFC_EVICT_INODE);
1388         metamapping = gfs2_glock2aspace(ip->i_gl);
1389         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1390                 filemap_fdatawrite(metamapping);
1391                 filemap_fdatawait(metamapping);
1392         }
1393         write_inode_now(inode, 1);
1394         gfs2_ail_flush(ip->i_gl, 0);
1395
1396         ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1397         if (ret)
1398                 return ret;
1399
1400         /* Needs to be done before glock release & also in a transaction */
1401         truncate_inode_pages(&inode->i_data, 0);
1402         truncate_inode_pages(metamapping, 0);
1403         gfs2_trans_end(sdp);
1404         return 0;
1405 }
1406
1407 /**
1408  * gfs2_evict_inode - Remove an inode from cache
1409  * @inode: The inode to evict
1410  *
1411  * There are three cases to consider:
1412  * 1. i_nlink == 0, we are final opener (and must deallocate)
1413  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1414  * 3. i_nlink > 0
1415  *
1416  * If the fs is read only, then we have to treat all cases as per #3
1417  * since we are unable to do any deallocation. The inode will be
1418  * deallocated by the next read/write node to attempt an allocation
1419  * in the same resource group
1420  *
1421  * We have to (at the moment) hold the inodes main lock to cover
1422  * the gap between unlocking the shared lock on the iopen lock and
1423  * taking the exclusive lock. I'd rather do a shared -> exclusive
1424  * conversion on the iopen lock, but we can change that later. This
1425  * is safe, just less efficient.
1426  */
1427
1428 static void gfs2_evict_inode(struct inode *inode)
1429 {
1430         struct super_block *sb = inode->i_sb;
1431         struct gfs2_sbd *sdp = sb->s_fs_info;
1432         struct gfs2_inode *ip = GFS2_I(inode);
1433         struct gfs2_holder gh;
1434         int ret;
1435
1436         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1437                 clear_inode(inode);
1438                 return;
1439         }
1440
1441         if (inode->i_nlink || sb_rdonly(sb))
1442                 goto out;
1443
1444         gfs2_holder_mark_uninitialized(&gh);
1445         ret = evict_should_delete(inode, &gh);
1446         if (ret == SHOULD_DEFER_EVICTION)
1447                 goto out;
1448         if (ret == SHOULD_DELETE_DINODE)
1449                 ret = evict_unlinked_inode(inode);
1450         else
1451                 ret = evict_linked_inode(inode);
1452
1453         if (gfs2_rs_active(&ip->i_res))
1454                 gfs2_rs_deltree(&ip->i_res);
1455
1456         if (gfs2_holder_initialized(&gh)) {
1457                 glock_clear_object(ip->i_gl, ip);
1458                 gfs2_glock_dq_uninit(&gh);
1459         }
1460         if (ret && ret != GLR_TRYFAILED && ret != -EROFS)
1461                 fs_warn(sdp, "gfs2_evict_inode: %d\n", ret);
1462 out:
1463         truncate_inode_pages_final(&inode->i_data);
1464         if (ip->i_qadata)
1465                 gfs2_assert_warn(sdp, ip->i_qadata->qa_ref == 0);
1466         gfs2_rs_delete(ip, NULL);
1467         gfs2_ordered_del_inode(ip);
1468         clear_inode(inode);
1469         gfs2_dir_hash_inval(ip);
1470         if (ip->i_gl) {
1471                 glock_clear_object(ip->i_gl, ip);
1472                 wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
1473                 gfs2_glock_add_to_lru(ip->i_gl);
1474                 gfs2_glock_put_eventually(ip->i_gl);
1475                 ip->i_gl = NULL;
1476         }
1477         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1478                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1479
1480                 glock_clear_object(gl, ip);
1481                 if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1482                         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1483                         gfs2_glock_dq(&ip->i_iopen_gh);
1484                 }
1485                 gfs2_glock_hold(gl);
1486                 gfs2_holder_uninit(&ip->i_iopen_gh);
1487                 gfs2_glock_put_eventually(gl);
1488         }
1489 }
1490
1491 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1492 {
1493         struct gfs2_inode *ip;
1494
1495         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1496         if (!ip)
1497                 return NULL;
1498         ip->i_flags = 0;
1499         ip->i_gl = NULL;
1500         gfs2_holder_mark_uninitialized(&ip->i_iopen_gh);
1501         memset(&ip->i_res, 0, sizeof(ip->i_res));
1502         RB_CLEAR_NODE(&ip->i_res.rs_node);
1503         ip->i_rahead = 0;
1504         return &ip->i_inode;
1505 }
1506
1507 static void gfs2_free_inode(struct inode *inode)
1508 {
1509         kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
1510 }
1511
1512 extern void free_local_statfs_inodes(struct gfs2_sbd *sdp)
1513 {
1514         struct local_statfs_inode *lsi, *safe;
1515
1516         /* Run through the statfs inodes list to iput and free memory */
1517         list_for_each_entry_safe(lsi, safe, &sdp->sd_sc_inodes_list, si_list) {
1518                 if (lsi->si_jid == sdp->sd_jdesc->jd_jid)
1519                         sdp->sd_sc_inode = NULL; /* belongs to this node */
1520                 if (lsi->si_sc_inode)
1521                         iput(lsi->si_sc_inode);
1522                 list_del(&lsi->si_list);
1523                 kfree(lsi);
1524         }
1525 }
1526
1527 extern struct inode *find_local_statfs_inode(struct gfs2_sbd *sdp,
1528                                              unsigned int index)
1529 {
1530         struct local_statfs_inode *lsi;
1531
1532         /* Return the local (per node) statfs inode in the
1533          * sdp->sd_sc_inodes_list corresponding to the 'index'. */
1534         list_for_each_entry(lsi, &sdp->sd_sc_inodes_list, si_list) {
1535                 if (lsi->si_jid == index)
1536                         return lsi->si_sc_inode;
1537         }
1538         return NULL;
1539 }
1540
1541 const struct super_operations gfs2_super_ops = {
1542         .alloc_inode            = gfs2_alloc_inode,
1543         .free_inode             = gfs2_free_inode,
1544         .write_inode            = gfs2_write_inode,
1545         .dirty_inode            = gfs2_dirty_inode,
1546         .evict_inode            = gfs2_evict_inode,
1547         .put_super              = gfs2_put_super,
1548         .sync_fs                = gfs2_sync_fs,
1549         .freeze_super           = gfs2_freeze,
1550         .thaw_super             = gfs2_unfreeze,
1551         .statfs                 = gfs2_statfs,
1552         .drop_inode             = gfs2_drop_inode,
1553         .show_options           = gfs2_show_options,
1554 };
1555