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 /**
 123  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 124  * @sdp: the filesystem
 125  *
 126  * Returns: errno
 127  */
 128
 129 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 130 {
 131         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 132         struct gfs2_glock *j_gl = ip->i_gl;
 133         struct gfs2_log_header_host head;
 134         int error;
 135
 136         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 137         if (gfs2_withdrawn(sdp))
 138                 return -EIO;
 139
 140         error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
 141         if (error || gfs2_withdrawn(sdp))
 142                 return error;
 143
 144         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 145                 gfs2_consist(sdp);
 146                 return -EIO;
 147         }
 148
 149         /*  Initialize some head of the log stuff  */
 150         sdp->sd_log_sequence = head.lh_sequence + 1;
 151         gfs2_log_pointers_init(sdp, head.lh_blkno);
 152
 153         error = gfs2_quota_init(sdp);
 154         if (!error && !gfs2_withdrawn(sdp))
 155                 set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 156         return error;
 157 }
 158
 159 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 160 {
 161         const struct gfs2_statfs_change *str = buf;
 162
 163         sc->sc_total = be64_to_cpu(str->sc_total);
 164         sc->sc_free = be64_to_cpu(str->sc_free);
 165         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 166 }
 167
 168 void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 169 {
 170         struct gfs2_statfs_change *str = buf;
 171
 172         str->sc_total = cpu_to_be64(sc->sc_total);
 173         str->sc_free = cpu_to_be64(sc->sc_free);
 174         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 175 }
 176
 177 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 178 {
 179         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 180         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 181         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 182         struct buffer_head *m_bh;
 183         struct gfs2_holder gh;
 184         int error;
 185
 186         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 187                                    &gh);
 188         if (error)
 189                 return error;
 190
 191         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 192         if (error)
 193                 goto out;
 194
 195         if (sdp->sd_args.ar_spectator) {
 196                 spin_lock(&sdp->sd_statfs_spin);
 197                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 198                                       sizeof(struct gfs2_dinode));
 199                 spin_unlock(&sdp->sd_statfs_spin);
 200         } else {
 201                 spin_lock(&sdp->sd_statfs_spin);
 202                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 203                                       sizeof(struct gfs2_dinode));
 204                 gfs2_statfs_change_in(l_sc, sdp->sd_sc_bh->b_data +
 205                                       sizeof(struct gfs2_dinode));
 206                 spin_unlock(&sdp->sd_statfs_spin);
 207
 208         }
 209
 210         brelse(m_bh);
 211 out:
 212         gfs2_glock_dq_uninit(&gh);
 213         return 0;
 214 }
 215
 216 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 217                         s64 dinodes)
 218 {
 219         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 220         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 221         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 222         s64 x, y;
 223         int need_sync = 0;
 224
 225         gfs2_trans_add_meta(l_ip->i_gl, sdp->sd_sc_bh);
 226
 227         spin_lock(&sdp->sd_statfs_spin);
 228         l_sc->sc_total += total;
 229         l_sc->sc_free += free;
 230         l_sc->sc_dinodes += dinodes;
 231         gfs2_statfs_change_out(l_sc, sdp->sd_sc_bh->b_data +
 232                                sizeof(struct gfs2_dinode));
 233         if (sdp->sd_args.ar_statfs_percent) {
 234                 x = 100 * l_sc->sc_free;
 235                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 236                 if (x >= y || x <= -y)
 237                         need_sync = 1;
 238         }
 239         spin_unlock(&sdp->sd_statfs_spin);
 240
 241         if (need_sync)
 242                 gfs2_wake_up_statfs(sdp);
 243 }
 244
 245 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh)
 246 {
 247         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 248         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 249         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 250         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 251
 252         gfs2_trans_add_meta(l_ip->i_gl, sdp->sd_sc_bh);
 253         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
 254
 255         spin_lock(&sdp->sd_statfs_spin);
 256         m_sc->sc_total += l_sc->sc_total;
 257         m_sc->sc_free += l_sc->sc_free;
 258         m_sc->sc_dinodes += l_sc->sc_dinodes;
 259         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 260         memset(sdp->sd_sc_bh->b_data + sizeof(struct gfs2_dinode),
 261                0, sizeof(struct gfs2_statfs_change));
 262         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 263         spin_unlock(&sdp->sd_statfs_spin);
 264 }
 265
 266 int gfs2_statfs_sync(struct super_block *sb, int type)
 267 {
 268         struct gfs2_sbd *sdp = sb->s_fs_info;
 269         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 270         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 271         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 272         struct gfs2_holder gh;
 273         struct buffer_head *m_bh;
 274         int error;
 275
 276         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 277                                    &gh);
 278         if (error)
 279                 goto out;
 280
 281         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 282         if (error)
 283                 goto out_unlock;
 284
 285         spin_lock(&sdp->sd_statfs_spin);
 286         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 287                               sizeof(struct gfs2_dinode));
 288         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 289                 spin_unlock(&sdp->sd_statfs_spin);
 290                 goto out_bh;
 291         }
 292         spin_unlock(&sdp->sd_statfs_spin);
 293
 294         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 295         if (error)
 296                 goto out_bh;
 297
 298         update_statfs(sdp, m_bh);
 299         sdp->sd_statfs_force_sync = 0;
 300
 301         gfs2_trans_end(sdp);
 302
 303 out_bh:
 304         brelse(m_bh);
 305 out_unlock:
 306         gfs2_glock_dq_uninit(&gh);
 307 out:
 308         return error;
 309 }
 310
 311 struct lfcc {
 312         struct list_head list;
 313         struct gfs2_holder gh;
 314 };
 315
 316 /**
 317  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 318  *                            journals are clean
 319  * @sdp: the file system
 320  *
 321  * Returns: errno
 322  */
 323
 324 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
 325 {
 326         struct gfs2_inode *ip;
 327         struct gfs2_jdesc *jd;
 328         struct lfcc *lfcc;
 329         LIST_HEAD(list);
 330         struct gfs2_log_header_host lh;
 331         int error;
 332
 333         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 334                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 335                 if (!lfcc) {
 336                         error = -ENOMEM;
 337                         goto out;
 338                 }
 339                 ip = GFS2_I(jd->jd_inode);
 340                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 341                 if (error) {
 342                         kfree(lfcc);
 343                         goto out;
 344                 }
 345                 list_add(&lfcc->list, &list);
 346         }
 347
 348         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
 349                                    LM_FLAG_NOEXP | GL_NOPID,
 350                                    &sdp->sd_freeze_gh);
 351         if (error)
 352                 goto out;
 353
 354         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 355                 error = gfs2_jdesc_check(jd);
 356                 if (error)
 357                         break;
 358                 error = gfs2_find_jhead(jd, &lh, false);
 359                 if (error)
 360                         break;
 361                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 362                         error = -EBUSY;
 363                         break;
 364                 }
 365         }
 366
 367         if (error)
 368                 gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 369
 370 out:
 371         while (!list_empty(&list)) {
 372                 lfcc = list_first_entry(&list, struct lfcc, list);
 373                 list_del(&lfcc->list);
 374                 gfs2_glock_dq_uninit(&lfcc->gh);
 375                 kfree(lfcc);
 376         }
 377         return error;
 378 }
 379
 380 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 381 {
 382         struct gfs2_dinode *str = buf;
 383
 384         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 385         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
 386         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
 387         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
 388         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
 389         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
 390         str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
 391         str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
 392         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
 393         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
 394         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
 395         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
 396         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
 397         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
 398
 399         str->di_goal_meta = cpu_to_be64(ip->i_goal);
 400         str->di_goal_data = cpu_to_be64(ip->i_goal);
 401         str->di_generation = cpu_to_be64(ip->i_generation);
 402
 403         str->di_flags = cpu_to_be32(ip->i_diskflags);
 404         str->di_height = cpu_to_be16(ip->i_height);
 405         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
 406                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
 407                                              GFS2_FORMAT_DE : 0);
 408         str->di_depth = cpu_to_be16(ip->i_depth);
 409         str->di_entries = cpu_to_be32(ip->i_entries);
 410
 411         str->di_eattr = cpu_to_be64(ip->i_eattr);
 412         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
 413         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
 414         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
 415 }
 416
 417 /**
 418  * gfs2_write_inode - Make sure the inode is stable on the disk
 419  * @inode: The inode
 420  * @wbc: The writeback control structure
 421  *
 422  * Returns: errno
 423  */
 424
 425 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 426 {
 427         struct gfs2_inode *ip = GFS2_I(inode);
 428         struct gfs2_sbd *sdp = GFS2_SB(inode);
 429         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
 430         struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
 431         int ret = 0;
 432         bool flush_all = (wbc->sync_mode == WB_SYNC_ALL || gfs2_is_jdata(ip));
 433
 434         if (flush_all)
 435                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl,
 436                                GFS2_LOG_HEAD_FLUSH_NORMAL |
 437                                GFS2_LFC_WRITE_INODE);
 438         if (bdi->wb.dirty_exceeded)
 439                 gfs2_ail1_flush(sdp, wbc);
 440         else
 441                 filemap_fdatawrite(metamapping);
 442         if (flush_all)
 443                 ret = filemap_fdatawait(metamapping);
 444         if (ret)
 445                 mark_inode_dirty_sync(inode);
 446         else {
 447                 spin_lock(&inode->i_lock);
 448                 if (!(inode->i_flags & I_DIRTY))
 449                         gfs2_ordered_del_inode(ip);
 450                 spin_unlock(&inode->i_lock);
 451         }
 452         return ret;
 453 }
 454
 455 /**
 456  * gfs2_dirty_inode - check for atime updates
 457  * @inode: The inode in question
 458  * @flags: The type of dirty
 459  *
 460  * Unfortunately it can be called under any combination of inode
 461  * glock and transaction lock, so we have to check carefully.
 462  *
 463  * At the moment this deals only with atime - it should be possible
 464  * to expand that role in future, once a review of the locking has
 465  * been carried out.
 466  */
 467
 468 static void gfs2_dirty_inode(struct inode *inode, int flags)
 469 {
 470         struct gfs2_inode *ip = GFS2_I(inode);
 471         struct gfs2_sbd *sdp = GFS2_SB(inode);
 472         struct buffer_head *bh;
 473         struct gfs2_holder gh;
 474         int need_unlock = 0;
 475         int need_endtrans = 0;
 476         int ret;
 477
 478         if (unlikely(gfs2_withdrawn(sdp)))
 479                 return;
 480         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 481                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 482                 if (ret) {
 483                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
 484                         gfs2_dump_glock(NULL, ip->i_gl, true);
 485                         return;
 486                 }
 487                 need_unlock = 1;
 488         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
 489                 return;
 490
 491         if (current->journal_info == NULL) {
 492                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 493                 if (ret) {
 494                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
 495                         goto out;
 496                 }
 497                 need_endtrans = 1;
 498         }
 499
 500         ret = gfs2_meta_inode_buffer(ip, &bh);
 501         if (ret == 0) {
 502                 gfs2_trans_add_meta(ip->i_gl, bh);
 503                 gfs2_dinode_out(ip, bh->b_data);
 504                 brelse(bh);
 505         }
 506
 507         if (need_endtrans)
 508                 gfs2_trans_end(sdp);
 509 out:
 510         if (need_unlock)
 511                 gfs2_glock_dq_uninit(&gh);
 512 }
 513
 514 /**
 515  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 516  * @sdp: the filesystem
 517  *
 518  * Returns: errno
 519  */
 520
 521 void gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 522 {
 523         int log_write_allowed = test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 524
 525         gfs2_flush_delete_work(sdp);
 526         if (!log_write_allowed && current == sdp->sd_quotad_process)
 527                 fs_warn(sdp, "The quotad daemon is withdrawing.\n");
 528         else if (sdp->sd_quotad_process)
 529                 kthread_stop(sdp->sd_quotad_process);
 530         sdp->sd_quotad_process = NULL;
 531
 532         if (!log_write_allowed && current == sdp->sd_logd_process)
 533                 fs_warn(sdp, "The logd daemon is withdrawing.\n");
 534         else if (sdp->sd_logd_process)
 535                 kthread_stop(sdp->sd_logd_process);
 536         sdp->sd_logd_process = NULL;
 537
 538         if (log_write_allowed) {
 539                 gfs2_quota_sync(sdp->sd_vfs, 0);
 540                 gfs2_statfs_sync(sdp->sd_vfs, 0);
 541
 542                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 543                                GFS2_LFC_MAKE_FS_RO);
 544                 wait_event_timeout(sdp->sd_log_waitq,
 545                                    gfs2_log_is_empty(sdp),
 546                                    HZ * 5);
 547                 gfs2_assert_warn(sdp, gfs2_log_is_empty(sdp));
 548         } else {
 549                 wait_event_timeout(sdp->sd_log_waitq,
 550                                    gfs2_log_is_empty(sdp),
 551                                    HZ * 5);
 552         }
 553         gfs2_quota_cleanup(sdp);
 554
 555         if (!log_write_allowed)
 556                 sdp->sd_vfs->s_flags |= SB_RDONLY;
 557 }
 558
 559 /**
 560  * gfs2_put_super - Unmount the filesystem
 561  * @sb: The VFS superblock
 562  *
 563  */
 564
 565 static void gfs2_put_super(struct super_block *sb)
 566 {
 567         struct gfs2_sbd *sdp = sb->s_fs_info;
 568         struct gfs2_jdesc *jd;
 569
 570         /* No more recovery requests */
 571         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 572         smp_mb();
 573
 574         /* Wait on outstanding recovery */
 575 restart:
 576         spin_lock(&sdp->sd_jindex_spin);
 577         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 578                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 579                         continue;
 580                 spin_unlock(&sdp->sd_jindex_spin);
 581                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 582                             TASK_UNINTERRUPTIBLE);
 583                 goto restart;
 584         }
 585         spin_unlock(&sdp->sd_jindex_spin);
 586
 587         if (!sb_rdonly(sb)) {
 588                 gfs2_make_fs_ro(sdp);
 589         }
 590         WARN_ON(gfs2_withdrawing(sdp));
 591
 592         /*  At this point, we're through modifying the disk  */
 593
 594         /*  Release stuff  */
 595
 596         iput(sdp->sd_jindex);
 597         iput(sdp->sd_statfs_inode);
 598         iput(sdp->sd_rindex);
 599         iput(sdp->sd_quota_inode);
 600
 601         gfs2_glock_put(sdp->sd_rename_gl);
 602         gfs2_glock_put(sdp->sd_freeze_gl);
 603
 604         if (!sdp->sd_args.ar_spectator) {
 605                 if (gfs2_holder_initialized(&sdp->sd_journal_gh))
 606                         gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 607                 if (gfs2_holder_initialized(&sdp->sd_jinode_gh))
 608                         gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 609                 brelse(sdp->sd_sc_bh);
 610                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 611                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 612                 free_local_statfs_inodes(sdp);
 613                 iput(sdp->sd_qc_inode);
 614         }
 615
 616         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 617         gfs2_clear_rgrpd(sdp);
 618         gfs2_jindex_free(sdp);
 619         /*  Take apart glock structures and buffer lists  */
 620         gfs2_gl_hash_clear(sdp);
 621         truncate_inode_pages_final(&sdp->sd_aspace);
 622         gfs2_delete_debugfs_file(sdp);
 623         /*  Unmount the locking protocol  */
 624         gfs2_lm_unmount(sdp);
 625
 626         /*  At this point, we're through participating in the lockspace  */
 627         gfs2_sys_fs_del(sdp);
 628         free_sbd(sdp);
 629 }
 630
 631 /**
 632  * gfs2_sync_fs - sync the filesystem
 633  * @sb: the superblock
 634  * @wait: true to wait for completion
 635  *
 636  * Flushes the log to disk.
 637  */
 638
 639 static int gfs2_sync_fs(struct super_block *sb, int wait)
 640 {
 641         struct gfs2_sbd *sdp = sb->s_fs_info;
 642
 643         gfs2_quota_sync(sb, -1);
 644         if (wait)
 645                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 646                                GFS2_LFC_SYNC_FS);
 647         return sdp->sd_log_error;
 648 }
 649
 650 void gfs2_freeze_func(struct work_struct *work)
 651 {
 652         int error;
 653         struct gfs2_holder freeze_gh;
 654         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
 655         struct super_block *sb = sdp->sd_vfs;
 656
 657         atomic_inc(&sb->s_active);
 658         error = gfs2_freeze_lock(sdp, &freeze_gh, 0);
 659         if (error) {
 660                 gfs2_assert_withdraw(sdp, 0);
 661         } else {
 662                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 663                 error = thaw_super(sb);
 664                 if (error) {
 665                         fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n",
 666                                 error);
 667                         gfs2_assert_withdraw(sdp, 0);
 668                 }
 669                 gfs2_freeze_unlock(&freeze_gh);
 670         }
 671         deactivate_super(sb);
 672         clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
 673         wake_up_bit(&sdp->sd_flags, SDF_FS_FROZEN);
 674         return;
 675 }
 676
 677 /**
 678  * gfs2_freeze - prevent further writes to the filesystem
 679  * @sb: the VFS structure for the filesystem
 680  *
 681  */
 682
 683 static int gfs2_freeze(struct super_block *sb)
 684 {
 685         struct gfs2_sbd *sdp = sb->s_fs_info;
 686         int error;
 687
 688         mutex_lock(&sdp->sd_freeze_mutex);
 689         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN) {
 690                 error = -EBUSY;
 691                 goto out;
 692         }
 693
 694         for (;;) {
 695                 if (gfs2_withdrawn(sdp)) {
 696                         error = -EINVAL;
 697                         goto out;
 698                 }
 699
 700                 error = gfs2_lock_fs_check_clean(sdp);
 701                 if (!error)
 702                         break;
 703
 704                 if (error == -EBUSY)
 705                         fs_err(sdp, "waiting for recovery before freeze\n");
 706                 else if (error == -EIO) {
 707                         fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
 708                                "to recovery error.\n");
 709                         goto out;
 710                 } else {
 711                         fs_err(sdp, "error freezing FS: %d\n", error);
 712                 }
 713                 fs_err(sdp, "retrying...\n");
 714                 msleep(1000);
 715         }
 716         set_bit(SDF_FS_FROZEN, &sdp->sd_flags);
 717 out:
 718         mutex_unlock(&sdp->sd_freeze_mutex);
 719         return error;
 720 }
 721
 722 /**
 723  * gfs2_unfreeze - reallow writes to the filesystem
 724  * @sb: the VFS structure for the filesystem
 725  *
 726  */
 727
 728 static int gfs2_unfreeze(struct super_block *sb)
 729 {
 730         struct gfs2_sbd *sdp = sb->s_fs_info;
 731
 732         mutex_lock(&sdp->sd_freeze_mutex);
 733         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
 734             !gfs2_holder_initialized(&sdp->sd_freeze_gh)) {
 735                 mutex_unlock(&sdp->sd_freeze_mutex);
 736                 return -EINVAL;
 737         }
 738
 739         gfs2_freeze_unlock(&sdp->sd_freeze_gh);
 740         mutex_unlock(&sdp->sd_freeze_mutex);
 741         return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 742 }
 743
 744 /**
 745  * statfs_slow_fill - fill in the sg for a given RG
 746  * @rgd: the RG
 747  * @sc: the sc structure
 748  *
 749  * Returns: 0 on success, -ESTALE if the LVB is invalid
 750  */
 751
 752 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 753                             struct gfs2_statfs_change_host *sc)
 754 {
 755         gfs2_rgrp_verify(rgd);
 756         sc->sc_total += rgd->rd_data;
 757         sc->sc_free += rgd->rd_free;
 758         sc->sc_dinodes += rgd->rd_dinodes;
 759         return 0;
 760 }
 761
 762 /**
 763  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 764  * @sdp: the filesystem
 765  * @sc: the sc info that will be returned
 766  *
 767  * Any error (other than a signal) will cause this routine to fall back
 768  * to the synchronous version.
 769  *
 770  * FIXME: This really shouldn't busy wait like this.
 771  *
 772  * Returns: errno
 773  */
 774
 775 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 776 {
 777         struct gfs2_rgrpd *rgd_next;
 778         struct gfs2_holder *gha, *gh;
 779         unsigned int slots = 64;
 780         unsigned int x;
 781         int done;
 782         int error = 0, err;
 783
 784         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 785         gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 786         if (!gha)
 787                 return -ENOMEM;
 788         for (x = 0; x < slots; x++)
 789                 gfs2_holder_mark_uninitialized(gha + x);
 790
 791         rgd_next = gfs2_rgrpd_get_first(sdp);
 792
 793         for (;;) {
 794                 done = 1;
 795
 796                 for (x = 0; x < slots; x++) {
 797                         gh = gha + x;
 798
 799                         if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
 800                                 err = gfs2_glock_wait(gh);
 801                                 if (err) {
 802                                         gfs2_holder_uninit(gh);
 803                                         error = err;
 804                                 } else {
 805                                         if (!error) {
 806                                                 struct gfs2_rgrpd *rgd =
 807                                                         gfs2_glock2rgrp(gh->gh_gl);
 808
 809                                                 error = statfs_slow_fill(rgd, sc);
 810                                         }
 811                                         gfs2_glock_dq_uninit(gh);
 812                                 }
 813                         }
 814
 815                         if (gfs2_holder_initialized(gh))
 816                                 done = 0;
 817                         else if (rgd_next && !error) {
 818                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 819                                                            LM_ST_SHARED,
 820                                                            GL_ASYNC,
 821                                                            gh);
 822                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 823                                 done = 0;
 824                         }
 825
 826                         if (signal_pending(current))
 827                                 error = -ERESTARTSYS;
 828                 }
 829
 830                 if (done)
 831                         break;
 832
 833                 yield();
 834         }
 835
 836         kfree(gha);
 837         return error;
 838 }
 839
 840 /**
 841  * gfs2_statfs_i - Do a statfs
 842  * @sdp: the filesystem
 843  * @sc: the sc structure
 844  *
 845  * Returns: errno
 846  */
 847
 848 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 849 {
 850         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 851         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 852
 853         spin_lock(&sdp->sd_statfs_spin);
 854
 855         *sc = *m_sc;
 856         sc->sc_total += l_sc->sc_total;
 857         sc->sc_free += l_sc->sc_free;
 858         sc->sc_dinodes += l_sc->sc_dinodes;
 859
 860         spin_unlock(&sdp->sd_statfs_spin);
 861
 862         if (sc->sc_free < 0)
 863                 sc->sc_free = 0;
 864         if (sc->sc_free > sc->sc_total)
 865                 sc->sc_free = sc->sc_total;
 866         if (sc->sc_dinodes < 0)
 867                 sc->sc_dinodes = 0;
 868
 869         return 0;
 870 }
 871
 872 /**
 873  * gfs2_statfs - Gather and return stats about the filesystem
 874  * @dentry: The name of the link
 875  * @buf: The buffer
 876  *
 877  * Returns: 0 on success or error code
 878  */
 879
 880 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 881 {
 882         struct super_block *sb = dentry->d_sb;
 883         struct gfs2_sbd *sdp = sb->s_fs_info;
 884         struct gfs2_statfs_change_host sc;
 885         int error;
 886
 887         error = gfs2_rindex_update(sdp);
 888         if (error)
 889                 return error;
 890
 891         if (gfs2_tune_get(sdp, gt_statfs_slow))
 892                 error = gfs2_statfs_slow(sdp, &sc);
 893         else
 894                 error = gfs2_statfs_i(sdp, &sc);
 895
 896         if (error)
 897                 return error;
 898
 899         buf->f_type = GFS2_MAGIC;
 900         buf->f_bsize = sdp->sd_sb.sb_bsize;
 901         buf->f_blocks = sc.sc_total;
 902         buf->f_bfree = sc.sc_free;
 903         buf->f_bavail = sc.sc_free;
 904         buf->f_files = sc.sc_dinodes + sc.sc_free;
 905         buf->f_ffree = sc.sc_free;
 906         buf->f_namelen = GFS2_FNAMESIZE;
 907
 908         return 0;
 909 }
 910
 911 /**
 912  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 913  * @inode: The inode to drop
 914  *
 915  * If we've received a callback on an iopen lock then it's because a
 916  * remote node tried to deallocate the inode but failed due to this node
 917  * still having the inode open. Here we mark the link count zero
 918  * since we know that it must have reached zero if the GLF_DEMOTE flag
 919  * is set on the iopen glock. If we didn't do a disk read since the
 920  * remote node removed the final link then we might otherwise miss
 921  * this event. This check ensures that this node will deallocate the
 922  * inode's blocks, or alternatively pass the baton on to another
 923  * node for later deallocation.
 924  */
 925
 926 static int gfs2_drop_inode(struct inode *inode)
 927 {
 928         struct gfs2_inode *ip = GFS2_I(inode);
 929
 930         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) &&
 931             inode->i_nlink &&
 932             gfs2_holder_initialized(&ip->i_iopen_gh)) {
 933                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 934                 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
 935                         clear_nlink(inode);
 936         }
 937
 938         /*
 939          * When under memory pressure when an inode's link count has dropped to
 940          * zero, defer deleting the inode to the delete workqueue.  This avoids
 941          * calling into DLM under memory pressure, which can deadlock.
 942          */
 943         if (!inode->i_nlink &&
 944             unlikely(current->flags & PF_MEMALLOC) &&
 945             gfs2_holder_initialized(&ip->i_iopen_gh)) {
 946                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 947
 948                 gfs2_glock_hold(gl);
 949                 if (!gfs2_queue_delete_work(gl, 0))
 950                         gfs2_glock_queue_put(gl);
 951                 return 0;
 952         }
 953
 954         return generic_drop_inode(inode);
 955 }
 956
 957 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
 958 {
 959         do {
 960                 if (d1 == d2)
 961                         return 1;
 962                 d1 = d1->d_parent;
 963         } while (!IS_ROOT(d1));
 964         return 0;
 965 }
 966
 967 /**
 968  * gfs2_show_options - Show mount options for /proc/mounts
 969  * @s: seq_file structure
 970  * @root: root of this (sub)tree
 971  *
 972  * Returns: 0 on success or error code
 973  */
 974
 975 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
 976 {
 977         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
 978         struct gfs2_args *args = &sdp->sd_args;
 979         int val;
 980
 981         if (is_ancestor(root, sdp->sd_master_dir))
 982                 seq_puts(s, ",meta");
 983         if (args->ar_lockproto[0])
 984                 seq_show_option(s, "lockproto", args->ar_lockproto);
 985         if (args->ar_locktable[0])
 986                 seq_show_option(s, "locktable", args->ar_locktable);
 987         if (args->ar_hostdata[0])
 988                 seq_show_option(s, "hostdata", args->ar_hostdata);
 989         if (args->ar_spectator)
 990                 seq_puts(s, ",spectator");
 991         if (args->ar_localflocks)
 992                 seq_puts(s, ",localflocks");
 993         if (args->ar_debug)
 994                 seq_puts(s, ",debug");
 995         if (args->ar_posix_acl)
 996                 seq_puts(s, ",acl");
 997         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
 998                 char *state;
 999                 switch (args->ar_quota) {
1000                 case GFS2_QUOTA_OFF:
1001                         state = "off";
1002                         break;
1003                 case GFS2_QUOTA_ACCOUNT:
1004                         state = "account";
1005                         break;
1006                 case GFS2_QUOTA_ON:
1007                         state = "on";
1008                         break;
1009                 default:
1010                         state = "unknown";
1011                         break;
1012                 }
1013                 seq_printf(s, ",quota=%s", state);
1014         }
1015         if (args->ar_suiddir)
1016                 seq_puts(s, ",suiddir");
1017         if (args->ar_data != GFS2_DATA_DEFAULT) {
1018                 char *state;
1019                 switch (args->ar_data) {
1020                 case GFS2_DATA_WRITEBACK:
1021                         state = "writeback";
1022                         break;
1023                 case GFS2_DATA_ORDERED:
1024                         state = "ordered";
1025                         break;
1026                 default:
1027                         state = "unknown";
1028                         break;
1029                 }
1030                 seq_printf(s, ",data=%s", state);
1031         }
1032         if (args->ar_discard)
1033                 seq_puts(s, ",discard");
1034         val = sdp->sd_tune.gt_logd_secs;
1035         if (val != 30)
1036                 seq_printf(s, ",commit=%d", val);
1037         val = sdp->sd_tune.gt_statfs_quantum;
1038         if (val != 30)
1039                 seq_printf(s, ",statfs_quantum=%d", val);
1040         else if (sdp->sd_tune.gt_statfs_slow)
1041                 seq_puts(s, ",statfs_quantum=0");
1042         val = sdp->sd_tune.gt_quota_quantum;
1043         if (val != 60)
1044                 seq_printf(s, ",quota_quantum=%d", val);
1045         if (args->ar_statfs_percent)
1046                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1047         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1048                 const char *state;
1049
1050                 switch (args->ar_errors) {
1051                 case GFS2_ERRORS_WITHDRAW:
1052                         state = "withdraw";
1053                         break;
1054                 case GFS2_ERRORS_PANIC:
1055                         state = "panic";
1056                         break;
1057                 default:
1058                         state = "unknown";
1059                         break;
1060                 }
1061                 seq_printf(s, ",errors=%s", state);
1062         }
1063         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1064                 seq_puts(s, ",nobarrier");
1065         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1066                 seq_puts(s, ",demote_interface_used");
1067         if (args->ar_rgrplvb)
1068                 seq_puts(s, ",rgrplvb");
1069         if (args->ar_loccookie)
1070                 seq_puts(s, ",loccookie");
1071         return 0;
1072 }
1073
1074 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1075 {
1076         struct inode *inode = &ip->i_inode;
1077         struct gfs2_glock *gl = ip->i_gl;
1078
1079         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1080         truncate_inode_pages(&inode->i_data, 0);
1081
1082         if (atomic_read(&gl->gl_revokes) == 0) {
1083                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1084                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1085         }
1086 }
1087
1088 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1089 {
1090         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1091         struct gfs2_rgrpd *rgd;
1092         struct gfs2_holder gh;
1093         int error;
1094
1095         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1096                 gfs2_consist_inode(ip);
1097                 return -EIO;
1098         }
1099
1100         error = gfs2_rindex_update(sdp);
1101         if (error)
1102                 return error;
1103
1104         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1105         if (error)
1106                 return error;
1107
1108         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1109         if (!rgd) {
1110                 gfs2_consist_inode(ip);
1111                 error = -EIO;
1112                 goto out_qs;
1113         }
1114
1115         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE,
1116                                    LM_FLAG_NODE_SCOPE, &gh);
1117         if (error)
1118                 goto out_qs;
1119
1120         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1121                                  sdp->sd_jdesc->jd_blocks);
1122         if (error)
1123                 goto out_rg_gunlock;
1124
1125         gfs2_free_di(rgd, ip);
1126
1127         gfs2_final_release_pages(ip);
1128
1129         gfs2_trans_end(sdp);
1130
1131 out_rg_gunlock:
1132         gfs2_glock_dq_uninit(&gh);
1133 out_qs:
1134         gfs2_quota_unhold(ip);
1135         return error;
1136 }
1137
1138 /**
1139  * gfs2_glock_put_eventually
1140  * @gl: The glock to put
1141  *
1142  * When under memory pressure, trigger a deferred glock put to make sure we
1143  * won't call into DLM and deadlock.  Otherwise, put the glock directly.
1144  */
1145
1146 static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
1147 {
1148         if (current->flags & PF_MEMALLOC)
1149                 gfs2_glock_queue_put(gl);
1150         else
1151                 gfs2_glock_put(gl);
1152 }
1153
1154 static bool gfs2_upgrade_iopen_glock(struct inode *inode)
1155 {
1156         struct gfs2_inode *ip = GFS2_I(inode);
1157         struct gfs2_sbd *sdp = GFS2_SB(inode);
1158         struct gfs2_holder *gh = &ip->i_iopen_gh;
1159         long timeout = 5 * HZ;
1160         int error;
1161
1162         gh->gh_flags |= GL_NOCACHE;
1163         gfs2_glock_dq_wait(gh);
1164
1165         /*
1166          * If there are no other lock holders, we'll get the lock immediately.
1167          * Otherwise, the other nodes holding the lock will be notified about
1168          * our locking request.  If they don't have the inode open, they'll
1169          * evict the cached inode and release the lock.  Otherwise, if they
1170          * poke the inode glock, we'll take this as an indication that they
1171          * still need the iopen glock and that they'll take care of deleting
1172          * the inode when they're done.  As a last resort, if another node
1173          * keeps holding the iopen glock without showing any activity on the
1174          * inode glock, we'll eventually time out.
1175          *
1176          * Note that we're passing the LM_FLAG_TRY_1CB flag to the first
1177          * locking request as an optimization to notify lock holders as soon as
1178          * possible.  Without that flag, they'd be notified implicitly by the
1179          * second locking request.
1180          */
1181
1182         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, gh);
1183         error = gfs2_glock_nq(gh);
1184         if (error != GLR_TRYFAILED)
1185                 return !error;
1186
1187         gfs2_holder_reinit(LM_ST_EXCLUSIVE, GL_ASYNC | GL_NOCACHE, gh);
1188         error = gfs2_glock_nq(gh);
1189         if (error)
1190                 return false;
1191
1192         timeout = wait_event_interruptible_timeout(sdp->sd_async_glock_wait,
1193                 !test_bit(HIF_WAIT, &gh->gh_iflags) ||
1194                 test_bit(GLF_DEMOTE, &ip->i_gl->gl_flags),
1195                 timeout);
1196         if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) {
1197                 gfs2_glock_dq(gh);
1198                 return false;
1199         }
1200         return gfs2_glock_holder_ready(gh) == 0;
1201 }
1202
1203 /**
1204  * evict_should_delete - determine whether the inode is eligible for deletion
1205  * @inode: The inode to evict
1206  * @gh: The glock holder structure
1207  *
1208  * This function determines whether the evicted inode is eligible to be deleted
1209  * and locks the inode glock.
1210  *
1211  * Returns: the fate of the dinode
1212  */
1213 static enum dinode_demise evict_should_delete(struct inode *inode,
1214                                               struct gfs2_holder *gh)
1215 {
1216         struct gfs2_inode *ip = GFS2_I(inode);
1217         struct super_block *sb = inode->i_sb;
1218         struct gfs2_sbd *sdp = sb->s_fs_info;
1219         int ret;
1220
1221         if (test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1222                 BUG_ON(!gfs2_glock_is_locked_by_me(ip->i_gl));
1223                 goto should_delete;
1224         }
1225
1226         if (test_bit(GIF_DEFERRED_DELETE, &ip->i_flags))
1227                 return SHOULD_DEFER_EVICTION;
1228
1229         /* Deletes should never happen under memory pressure anymore.  */
1230         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
1231                 return SHOULD_DEFER_EVICTION;
1232
1233         /* Must not read inode block until block type has been verified */
1234         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, gh);
1235         if (unlikely(ret)) {
1236                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1237                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1238                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1239                 return SHOULD_DEFER_EVICTION;
1240         }
1241
1242         if (gfs2_inode_already_deleted(ip->i_gl, ip->i_no_formal_ino))
1243                 return SHOULD_NOT_DELETE_DINODE;
1244         ret = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1245         if (ret)
1246                 return SHOULD_NOT_DELETE_DINODE;
1247
1248         ret = gfs2_instantiate(gh);
1249         if (ret)
1250                 return SHOULD_NOT_DELETE_DINODE;
1251
1252         /*
1253          * The inode may have been recreated in the meantime.
1254          */
1255         if (inode->i_nlink)
1256                 return SHOULD_NOT_DELETE_DINODE;
1257
1258 should_delete:
1259         if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
1260             test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1261                 if (!gfs2_upgrade_iopen_glock(inode)) {
1262                         gfs2_holder_uninit(&ip->i_iopen_gh);
1263                         return SHOULD_NOT_DELETE_DINODE;
1264                 }
1265         }
1266         return SHOULD_DELETE_DINODE;
1267 }
1268
1269 /**
1270  * evict_unlinked_inode - delete the pieces of an unlinked evicted inode
1271  * @inode: The inode to evict
1272  */
1273 static int evict_unlinked_inode(struct inode *inode)
1274 {
1275         struct gfs2_inode *ip = GFS2_I(inode);
1276         int ret;
1277
1278         if (S_ISDIR(inode->i_mode) &&
1279             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1280                 ret = gfs2_dir_exhash_dealloc(ip);
1281                 if (ret)
1282                         goto out;
1283         }
1284
1285         if (ip->i_eattr) {
1286                 ret = gfs2_ea_dealloc(ip);
1287                 if (ret)
1288                         goto out;
1289         }
1290
1291         if (!gfs2_is_stuffed(ip)) {
1292                 ret = gfs2_file_dealloc(ip);
1293                 if (ret)
1294                         goto out;
1295         }
1296
1297         /* We're about to clear the bitmap for the dinode, but as soon as we
1298            do, gfs2_create_inode can create another inode at the same block
1299            location and try to set gl_object again. We clear gl_object here so
1300            that subsequent inode creates don't see an old gl_object. */
1301         glock_clear_object(ip->i_gl, ip);
1302         ret = gfs2_dinode_dealloc(ip);
1303         gfs2_inode_remember_delete(ip->i_gl, ip->i_no_formal_ino);
1304 out:
1305         return ret;
1306 }
1307
1308 /*
1309  * evict_linked_inode - evict an inode whose dinode has not been unlinked
1310  * @inode: The inode to evict
1311  */
1312 static int evict_linked_inode(struct inode *inode)
1313 {
1314         struct super_block *sb = inode->i_sb;
1315         struct gfs2_sbd *sdp = sb->s_fs_info;
1316         struct gfs2_inode *ip = GFS2_I(inode);
1317         struct address_space *metamapping;
1318         int ret;
1319
1320         gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
1321                        GFS2_LFC_EVICT_INODE);
1322         metamapping = gfs2_glock2aspace(ip->i_gl);
1323         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1324                 filemap_fdatawrite(metamapping);
1325                 filemap_fdatawait(metamapping);
1326         }
1327         write_inode_now(inode, 1);
1328         gfs2_ail_flush(ip->i_gl, 0);
1329
1330         ret = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1331         if (ret)
1332                 return ret;
1333
1334         /* Needs to be done before glock release & also in a transaction */
1335         truncate_inode_pages(&inode->i_data, 0);
1336         truncate_inode_pages(metamapping, 0);
1337         gfs2_trans_end(sdp);
1338         return 0;
1339 }
1340
1341 /**
1342  * gfs2_evict_inode - Remove an inode from cache
1343  * @inode: The inode to evict
1344  *
1345  * There are three cases to consider:
1346  * 1. i_nlink == 0, we are final opener (and must deallocate)
1347  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1348  * 3. i_nlink > 0
1349  *
1350  * If the fs is read only, then we have to treat all cases as per #3
1351  * since we are unable to do any deallocation. The inode will be
1352  * deallocated by the next read/write node to attempt an allocation
1353  * in the same resource group
1354  *
1355  * We have to (at the moment) hold the inodes main lock to cover
1356  * the gap between unlocking the shared lock on the iopen lock and
1357  * taking the exclusive lock. I'd rather do a shared -> exclusive
1358  * conversion on the iopen lock, but we can change that later. This
1359  * is safe, just less efficient.
1360  */
1361
1362 static void gfs2_evict_inode(struct inode *inode)
1363 {
1364         struct super_block *sb = inode->i_sb;
1365         struct gfs2_sbd *sdp = sb->s_fs_info;
1366         struct gfs2_inode *ip = GFS2_I(inode);
1367         struct gfs2_holder gh;
1368         int ret;
1369
1370         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1371                 clear_inode(inode);
1372                 return;
1373         }
1374
1375         if (inode->i_nlink || sb_rdonly(sb))
1376                 goto out;
1377
1378         gfs2_holder_mark_uninitialized(&gh);
1379         ret = evict_should_delete(inode, &gh);
1380         if (ret == SHOULD_DEFER_EVICTION)
1381                 goto out;
1382         if (ret == SHOULD_DELETE_DINODE)
1383                 ret = evict_unlinked_inode(inode);
1384         else
1385                 ret = evict_linked_inode(inode);
1386
1387         if (gfs2_rs_active(&ip->i_res))
1388                 gfs2_rs_deltree(&ip->i_res);
1389
1390         if (gfs2_holder_initialized(&gh)) {
1391                 glock_clear_object(ip->i_gl, ip);
1392                 gfs2_glock_dq_uninit(&gh);
1393         }
1394         if (ret && ret != GLR_TRYFAILED && ret != -EROFS)
1395                 fs_warn(sdp, "gfs2_evict_inode: %d\n", ret);
1396 out:
1397         truncate_inode_pages_final(&inode->i_data);
1398         if (ip->i_qadata)
1399                 gfs2_assert_warn(sdp, ip->i_qadata->qa_ref == 0);
1400         gfs2_rs_deltree(&ip->i_res);
1401         gfs2_ordered_del_inode(ip);
1402         clear_inode(inode);
1403         gfs2_dir_hash_inval(ip);
1404         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1405                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1406
1407                 glock_clear_object(gl, ip);
1408                 if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1409                         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1410                         gfs2_glock_dq(&ip->i_iopen_gh);
1411                 }
1412                 gfs2_glock_hold(gl);
1413                 gfs2_holder_uninit(&ip->i_iopen_gh);
1414                 gfs2_glock_put_eventually(gl);
1415         }
1416         if (ip->i_gl) {
1417                 glock_clear_object(ip->i_gl, ip);
1418                 wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
1419                 gfs2_glock_add_to_lru(ip->i_gl);
1420                 gfs2_glock_put_eventually(ip->i_gl);
1421                 ip->i_gl = NULL;
1422         }
1423 }
1424
1425 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1426 {
1427         struct gfs2_inode *ip;
1428
1429         ip = alloc_inode_sb(sb, gfs2_inode_cachep, GFP_KERNEL);
1430         if (!ip)
1431                 return NULL;
1432         ip->i_flags = 0;
1433         ip->i_gl = NULL;
1434         gfs2_holder_mark_uninitialized(&ip->i_iopen_gh);
1435         memset(&ip->i_res, 0, sizeof(ip->i_res));
1436         RB_CLEAR_NODE(&ip->i_res.rs_node);
1437         ip->i_rahead = 0;
1438         return &ip->i_inode;
1439 }
1440
1441 static void gfs2_free_inode(struct inode *inode)
1442 {
1443         kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
1444 }
1445
1446 extern void free_local_statfs_inodes(struct gfs2_sbd *sdp)
1447 {
1448         struct local_statfs_inode *lsi, *safe;
1449
1450         /* Run through the statfs inodes list to iput and free memory */
1451         list_for_each_entry_safe(lsi, safe, &sdp->sd_sc_inodes_list, si_list) {
1452                 if (lsi->si_jid == sdp->sd_jdesc->jd_jid)
1453                         sdp->sd_sc_inode = NULL; /* belongs to this node */
1454                 if (lsi->si_sc_inode)
1455                         iput(lsi->si_sc_inode);
1456                 list_del(&lsi->si_list);
1457                 kfree(lsi);
1458         }
1459 }
1460
1461 extern struct inode *find_local_statfs_inode(struct gfs2_sbd *sdp,
1462                                              unsigned int index)
1463 {
1464         struct local_statfs_inode *lsi;
1465
1466         /* Return the local (per node) statfs inode in the
1467          * sdp->sd_sc_inodes_list corresponding to the 'index'. */
1468         list_for_each_entry(lsi, &sdp->sd_sc_inodes_list, si_list) {
1469                 if (lsi->si_jid == index)
1470                         return lsi->si_sc_inode;
1471         }
1472         return NULL;
1473 }
1474
1475 const struct super_operations gfs2_super_ops = {
1476         .alloc_inode            = gfs2_alloc_inode,
1477         .free_inode             = gfs2_free_inode,
1478         .write_inode            = gfs2_write_inode,
1479         .dirty_inode            = gfs2_dirty_inode,
1480         .evict_inode            = gfs2_evict_inode,
1481         .put_super              = gfs2_put_super,
1482         .sync_fs                = gfs2_sync_fs,
1483         .freeze_super           = gfs2_freeze,
1484         .thaw_super             = gfs2_unfreeze,
1485         .statfs                 = gfs2_statfs,
1486         .drop_inode             = gfs2_drop_inode,
1487         .show_options           = gfs2_show_options,
1488 };
1489