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 /**
  48  * gfs2_jindex_free - Clear all the journal index information
  49  * @sdp: The GFS2 superblock
  50  *
  51  */
  52
  53 void gfs2_jindex_free(struct gfs2_sbd *sdp)
  54 {
  55         struct list_head list;
  56         struct gfs2_jdesc *jd;
  57
  58         spin_lock(&sdp->sd_jindex_spin);
  59         list_add(&list, &sdp->sd_jindex_list);
  60         list_del_init(&sdp->sd_jindex_list);
  61         sdp->sd_journals = 0;
  62         spin_unlock(&sdp->sd_jindex_spin);
  63
  64         while (!list_empty(&list)) {
  65                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
  66                 gfs2_free_journal_extents(jd);
  67                 list_del(&jd->jd_list);
  68                 iput(jd->jd_inode);
  69                 kfree(jd);
  70         }
  71 }
  72
  73 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
  74 {
  75         struct gfs2_jdesc *jd;
  76         int found = 0;
  77
  78         list_for_each_entry(jd, head, jd_list) {
  79                 if (jd->jd_jid == jid) {
  80                         found = 1;
  81                         break;
  82                 }
  83         }
  84
  85         if (!found)
  86                 jd = NULL;
  87
  88         return jd;
  89 }
  90
  91 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
  92 {
  93         struct gfs2_jdesc *jd;
  94
  95         spin_lock(&sdp->sd_jindex_spin);
  96         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
  97         spin_unlock(&sdp->sd_jindex_spin);
  98
  99         return jd;
 100 }
 101
 102 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
 103 {
 104         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 105         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 106         u64 size = i_size_read(jd->jd_inode);
 107
 108         if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, BIT(30)))
 109                 return -EIO;
 110
 111         jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
 112
 113         if (gfs2_write_alloc_required(ip, 0, size)) {
 114                 gfs2_consist_inode(ip);
 115                 return -EIO;
 116         }
 117
 118         return 0;
 119 }
 120
 121 static int init_threads(struct gfs2_sbd *sdp)
 122 {
 123         struct task_struct *p;
 124         int error = 0;
 125
 126         p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
 127         if (IS_ERR(p)) {
 128                 error = PTR_ERR(p);
 129                 fs_err(sdp, "can't start logd thread: %d\n", error);
 130                 return error;
 131         }
 132         sdp->sd_logd_process = p;
 133
 134         p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
 135         if (IS_ERR(p)) {
 136                 error = PTR_ERR(p);
 137                 fs_err(sdp, "can't start quotad thread: %d\n", error);
 138                 goto fail;
 139         }
 140         sdp->sd_quotad_process = p;
 141         return 0;
 142
 143 fail:
 144         kthread_stop(sdp->sd_logd_process);
 145         sdp->sd_logd_process = NULL;
 146         return error;
 147 }
 148
 149 /**
 150  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 151  * @sdp: the filesystem
 152  *
 153  * Returns: errno
 154  */
 155
 156 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 157 {
 158         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 159         struct gfs2_glock *j_gl = ip->i_gl;
 160         struct gfs2_holder freeze_gh;
 161         struct gfs2_log_header_host head;
 162         int error;
 163
 164         error = init_threads(sdp);
 165         if (error)
 166                 return error;
 167
 168         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
 169                                    &freeze_gh);
 170         if (error)
 171                 goto fail_threads;
 172
 173         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 174
 175         error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
 176         if (error)
 177                 goto fail;
 178
 179         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 180                 gfs2_consist(sdp);
 181                 error = -EIO;
 182                 goto fail;
 183         }
 184
 185         /*  Initialize some head of the log stuff  */
 186         sdp->sd_log_sequence = head.lh_sequence + 1;
 187         gfs2_log_pointers_init(sdp, head.lh_blkno);
 188
 189         error = gfs2_quota_init(sdp);
 190         if (error)
 191                 goto fail;
 192
 193         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 194
 195         gfs2_glock_dq_uninit(&freeze_gh);
 196
 197         return 0;
 198
 199 fail:
 200         freeze_gh.gh_flags |= GL_NOCACHE;
 201         gfs2_glock_dq_uninit(&freeze_gh);
 202 fail_threads:
 203         if (sdp->sd_quotad_process)
 204                 kthread_stop(sdp->sd_quotad_process);
 205         sdp->sd_quotad_process = NULL;
 206         if (sdp->sd_logd_process)
 207                 kthread_stop(sdp->sd_logd_process);
 208         sdp->sd_logd_process = NULL;
 209         return error;
 210 }
 211
 212 void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 213 {
 214         const struct gfs2_statfs_change *str = buf;
 215
 216         sc->sc_total = be64_to_cpu(str->sc_total);
 217         sc->sc_free = be64_to_cpu(str->sc_free);
 218         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 219 }
 220
 221 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 222 {
 223         struct gfs2_statfs_change *str = buf;
 224
 225         str->sc_total = cpu_to_be64(sc->sc_total);
 226         str->sc_free = cpu_to_be64(sc->sc_free);
 227         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 228 }
 229
 230 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 231 {
 232         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 233         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 234         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 235         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 236         struct buffer_head *m_bh, *l_bh;
 237         struct gfs2_holder gh;
 238         int error;
 239
 240         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 241                                    &gh);
 242         if (error)
 243                 return error;
 244
 245         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 246         if (error)
 247                 goto out;
 248
 249         if (sdp->sd_args.ar_spectator) {
 250                 spin_lock(&sdp->sd_statfs_spin);
 251                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 252                                       sizeof(struct gfs2_dinode));
 253                 spin_unlock(&sdp->sd_statfs_spin);
 254         } else {
 255                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 256                 if (error)
 257                         goto out_m_bh;
 258
 259                 spin_lock(&sdp->sd_statfs_spin);
 260                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 261                                       sizeof(struct gfs2_dinode));
 262                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 263                                       sizeof(struct gfs2_dinode));
 264                 spin_unlock(&sdp->sd_statfs_spin);
 265
 266                 brelse(l_bh);
 267         }
 268
 269 out_m_bh:
 270         brelse(m_bh);
 271 out:
 272         gfs2_glock_dq_uninit(&gh);
 273         return 0;
 274 }
 275
 276 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 277                         s64 dinodes)
 278 {
 279         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 280         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 281         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 282         struct buffer_head *l_bh;
 283         s64 x, y;
 284         int need_sync = 0;
 285         int error;
 286
 287         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 288         if (error)
 289                 return;
 290
 291         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 292
 293         spin_lock(&sdp->sd_statfs_spin);
 294         l_sc->sc_total += total;
 295         l_sc->sc_free += free;
 296         l_sc->sc_dinodes += dinodes;
 297         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 298         if (sdp->sd_args.ar_statfs_percent) {
 299                 x = 100 * l_sc->sc_free;
 300                 y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
 301                 if (x >= y || x <= -y)
 302                         need_sync = 1;
 303         }
 304         spin_unlock(&sdp->sd_statfs_spin);
 305
 306         brelse(l_bh);
 307         if (need_sync)
 308                 gfs2_wake_up_statfs(sdp);
 309 }
 310
 311 void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
 312                    struct buffer_head *l_bh)
 313 {
 314         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 315         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 316         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 317         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 318
 319         gfs2_trans_add_meta(l_ip->i_gl, l_bh);
 320         gfs2_trans_add_meta(m_ip->i_gl, m_bh);
 321
 322         spin_lock(&sdp->sd_statfs_spin);
 323         m_sc->sc_total += l_sc->sc_total;
 324         m_sc->sc_free += l_sc->sc_free;
 325         m_sc->sc_dinodes += l_sc->sc_dinodes;
 326         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 327         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 328                0, sizeof(struct gfs2_statfs_change));
 329         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 330         spin_unlock(&sdp->sd_statfs_spin);
 331 }
 332
 333 int gfs2_statfs_sync(struct super_block *sb, int type)
 334 {
 335         struct gfs2_sbd *sdp = sb->s_fs_info;
 336         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 337         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 338         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 339         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 340         struct gfs2_holder gh;
 341         struct buffer_head *m_bh, *l_bh;
 342         int error;
 343
 344         sb_start_write(sb);
 345         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 346                                    &gh);
 347         if (error)
 348                 goto out;
 349
 350         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 351         if (error)
 352                 goto out_unlock;
 353
 354         spin_lock(&sdp->sd_statfs_spin);
 355         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 356                               sizeof(struct gfs2_dinode));
 357         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 358                 spin_unlock(&sdp->sd_statfs_spin);
 359                 goto out_bh;
 360         }
 361         spin_unlock(&sdp->sd_statfs_spin);
 362
 363         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 364         if (error)
 365                 goto out_bh;
 366
 367         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 368         if (error)
 369                 goto out_bh2;
 370
 371         update_statfs(sdp, m_bh, l_bh);
 372         sdp->sd_statfs_force_sync = 0;
 373
 374         gfs2_trans_end(sdp);
 375
 376 out_bh2:
 377         brelse(l_bh);
 378 out_bh:
 379         brelse(m_bh);
 380 out_unlock:
 381         gfs2_glock_dq_uninit(&gh);
 382 out:
 383         sb_end_write(sb);
 384         return error;
 385 }
 386
 387 struct lfcc {
 388         struct list_head list;
 389         struct gfs2_holder gh;
 390 };
 391
 392 /**
 393  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 394  *                            journals are clean
 395  * @sdp: the file system
 396  * @state: the state to put the transaction lock into
 397  * @t_gh: the hold on the transaction lock
 398  *
 399  * Returns: errno
 400  */
 401
 402 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp)
 403 {
 404         struct gfs2_inode *ip;
 405         struct gfs2_jdesc *jd;
 406         struct lfcc *lfcc;
 407         LIST_HEAD(list);
 408         struct gfs2_log_header_host lh;
 409         int error;
 410
 411         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 412                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 413                 if (!lfcc) {
 414                         error = -ENOMEM;
 415                         goto out;
 416                 }
 417                 ip = GFS2_I(jd->jd_inode);
 418                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 419                 if (error) {
 420                         kfree(lfcc);
 421                         goto out;
 422                 }
 423                 list_add(&lfcc->list, &list);
 424         }
 425
 426         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
 427                                    GL_NOCACHE, &sdp->sd_freeze_gh);
 428         if (error)
 429                 goto out;
 430
 431         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 432                 error = gfs2_jdesc_check(jd);
 433                 if (error)
 434                         break;
 435                 error = gfs2_find_jhead(jd, &lh, false);
 436                 if (error)
 437                         break;
 438                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 439                         error = -EBUSY;
 440                         break;
 441                 }
 442         }
 443
 444         if (error)
 445                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 446
 447 out:
 448         while (!list_empty(&list)) {
 449                 lfcc = list_entry(list.next, struct lfcc, list);
 450                 list_del(&lfcc->list);
 451                 gfs2_glock_dq_uninit(&lfcc->gh);
 452                 kfree(lfcc);
 453         }
 454         return error;
 455 }
 456
 457 void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
 458 {
 459         struct gfs2_dinode *str = buf;
 460
 461         str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
 462         str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
 463         str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
 464         str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
 465         str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
 466         str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
 467         str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
 468         str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
 469         str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
 470         str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
 471         str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
 472         str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
 473         str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
 474         str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
 475
 476         str->di_goal_meta = cpu_to_be64(ip->i_goal);
 477         str->di_goal_data = cpu_to_be64(ip->i_goal);
 478         str->di_generation = cpu_to_be64(ip->i_generation);
 479
 480         str->di_flags = cpu_to_be32(ip->i_diskflags);
 481         str->di_height = cpu_to_be16(ip->i_height);
 482         str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
 483                                              !(ip->i_diskflags & GFS2_DIF_EXHASH) ?
 484                                              GFS2_FORMAT_DE : 0);
 485         str->di_depth = cpu_to_be16(ip->i_depth);
 486         str->di_entries = cpu_to_be32(ip->i_entries);
 487
 488         str->di_eattr = cpu_to_be64(ip->i_eattr);
 489         str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
 490         str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
 491         str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
 492 }
 493
 494 /**
 495  * gfs2_write_inode - Make sure the inode is stable on the disk
 496  * @inode: The inode
 497  * @wbc: The writeback control structure
 498  *
 499  * Returns: errno
 500  */
 501
 502 static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
 503 {
 504         struct gfs2_inode *ip = GFS2_I(inode);
 505         struct gfs2_sbd *sdp = GFS2_SB(inode);
 506         struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
 507         struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
 508         int ret = 0;
 509         bool flush_all = (wbc->sync_mode == WB_SYNC_ALL || gfs2_is_jdata(ip));
 510
 511         if (flush_all)
 512                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl,
 513                                GFS2_LOG_HEAD_FLUSH_NORMAL |
 514                                GFS2_LFC_WRITE_INODE);
 515         if (bdi->wb.dirty_exceeded)
 516                 gfs2_ail1_flush(sdp, wbc);
 517         else
 518                 filemap_fdatawrite(metamapping);
 519         if (flush_all)
 520                 ret = filemap_fdatawait(metamapping);
 521         if (ret)
 522                 mark_inode_dirty_sync(inode);
 523         else {
 524                 spin_lock(&inode->i_lock);
 525                 if (!(inode->i_flags & I_DIRTY))
 526                         gfs2_ordered_del_inode(ip);
 527                 spin_unlock(&inode->i_lock);
 528         }
 529         return ret;
 530 }
 531
 532 /**
 533  * gfs2_dirty_inode - check for atime updates
 534  * @inode: The inode in question
 535  * @flags: The type of dirty
 536  *
 537  * Unfortunately it can be called under any combination of inode
 538  * glock and transaction lock, so we have to check carefully.
 539  *
 540  * At the moment this deals only with atime - it should be possible
 541  * to expand that role in future, once a review of the locking has
 542  * been carried out.
 543  */
 544
 545 static void gfs2_dirty_inode(struct inode *inode, int flags)
 546 {
 547         struct gfs2_inode *ip = GFS2_I(inode);
 548         struct gfs2_sbd *sdp = GFS2_SB(inode);
 549         struct buffer_head *bh;
 550         struct gfs2_holder gh;
 551         int need_unlock = 0;
 552         int need_endtrans = 0;
 553         int ret;
 554
 555         if (!(flags & I_DIRTY_INODE))
 556                 return;
 557         if (unlikely(gfs2_withdrawn(sdp)))
 558                 return;
 559         if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
 560                 ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 561                 if (ret) {
 562                         fs_err(sdp, "dirty_inode: glock %d\n", ret);
 563                         return;
 564                 }
 565                 need_unlock = 1;
 566         } else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
 567                 return;
 568
 569         if (current->journal_info == NULL) {
 570                 ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
 571                 if (ret) {
 572                         fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
 573                         goto out;
 574                 }
 575                 need_endtrans = 1;
 576         }
 577
 578         ret = gfs2_meta_inode_buffer(ip, &bh);
 579         if (ret == 0) {
 580                 gfs2_trans_add_meta(ip->i_gl, bh);
 581                 gfs2_dinode_out(ip, bh->b_data);
 582                 brelse(bh);
 583         }
 584
 585         if (need_endtrans)
 586                 gfs2_trans_end(sdp);
 587 out:
 588         if (need_unlock)
 589                 gfs2_glock_dq_uninit(&gh);
 590 }
 591
 592 /**
 593  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
 594  * @sdp: the filesystem
 595  *
 596  * Returns: errno
 597  */
 598
 599 int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 600 {
 601         struct gfs2_holder freeze_gh;
 602         int error;
 603
 604         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_NOCACHE,
 605                                    &freeze_gh);
 606         if (error && !gfs2_withdrawn(sdp))
 607                 return error;
 608
 609         flush_workqueue(gfs2_delete_workqueue);
 610         if (sdp->sd_quotad_process)
 611                 kthread_stop(sdp->sd_quotad_process);
 612         sdp->sd_quotad_process = NULL;
 613         if (sdp->sd_logd_process)
 614                 kthread_stop(sdp->sd_logd_process);
 615         sdp->sd_logd_process = NULL;
 616
 617         gfs2_quota_sync(sdp->sd_vfs, 0);
 618         gfs2_statfs_sync(sdp->sd_vfs, 0);
 619
 620         gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SHUTDOWN |
 621                        GFS2_LFC_MAKE_FS_RO);
 622         wait_event(sdp->sd_reserving_log_wait, atomic_read(&sdp->sd_reserving_log) == 0);
 623         gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
 624
 625         if (gfs2_holder_initialized(&freeze_gh))
 626                 gfs2_glock_dq_uninit(&freeze_gh);
 627
 628         gfs2_quota_cleanup(sdp);
 629
 630         return error;
 631 }
 632
 633 /**
 634  * gfs2_put_super - Unmount the filesystem
 635  * @sb: The VFS superblock
 636  *
 637  */
 638
 639 static void gfs2_put_super(struct super_block *sb)
 640 {
 641         struct gfs2_sbd *sdp = sb->s_fs_info;
 642         int error;
 643         struct gfs2_jdesc *jd;
 644
 645         /* No more recovery requests */
 646         set_bit(SDF_NORECOVERY, &sdp->sd_flags);
 647         smp_mb();
 648
 649         /* Wait on outstanding recovery */
 650 restart:
 651         spin_lock(&sdp->sd_jindex_spin);
 652         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 653                 if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
 654                         continue;
 655                 spin_unlock(&sdp->sd_jindex_spin);
 656                 wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
 657                             TASK_UNINTERRUPTIBLE);
 658                 goto restart;
 659         }
 660         spin_unlock(&sdp->sd_jindex_spin);
 661
 662         if (!sb_rdonly(sb)) {
 663                 error = gfs2_make_fs_ro(sdp);
 664                 if (error)
 665                         gfs2_io_error(sdp);
 666         }
 667         /*  At this point, we're through modifying the disk  */
 668
 669         /*  Release stuff  */
 670
 671         iput(sdp->sd_jindex);
 672         iput(sdp->sd_statfs_inode);
 673         iput(sdp->sd_rindex);
 674         iput(sdp->sd_quota_inode);
 675
 676         gfs2_glock_put(sdp->sd_rename_gl);
 677         gfs2_glock_put(sdp->sd_freeze_gl);
 678
 679         if (!sdp->sd_args.ar_spectator) {
 680                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 681                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 682                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 683                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 684                 iput(sdp->sd_sc_inode);
 685                 iput(sdp->sd_qc_inode);
 686         }
 687
 688         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 689         gfs2_clear_rgrpd(sdp);
 690         gfs2_jindex_free(sdp);
 691         /*  Take apart glock structures and buffer lists  */
 692         gfs2_gl_hash_clear(sdp);
 693         gfs2_delete_debugfs_file(sdp);
 694         /*  Unmount the locking protocol  */
 695         gfs2_lm_unmount(sdp);
 696
 697         /*  At this point, we're through participating in the lockspace  */
 698         gfs2_sys_fs_del(sdp);
 699 }
 700
 701 /**
 702  * gfs2_sync_fs - sync the filesystem
 703  * @sb: the superblock
 704  *
 705  * Flushes the log to disk.
 706  */
 707
 708 static int gfs2_sync_fs(struct super_block *sb, int wait)
 709 {
 710         struct gfs2_sbd *sdp = sb->s_fs_info;
 711
 712         gfs2_quota_sync(sb, -1);
 713         if (wait)
 714                 gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
 715                                GFS2_LFC_SYNC_FS);
 716         return sdp->sd_log_error;
 717 }
 718
 719 void gfs2_freeze_func(struct work_struct *work)
 720 {
 721         int error;
 722         struct gfs2_holder freeze_gh;
 723         struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
 724         struct super_block *sb = sdp->sd_vfs;
 725
 726         atomic_inc(&sb->s_active);
 727         error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
 728                                    &freeze_gh);
 729         if (error) {
 730                 fs_info(sdp, "GFS2: couldn't get freeze lock : %d\n", error);
 731                 gfs2_assert_withdraw(sdp, 0);
 732         } else {
 733                 atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
 734                 error = thaw_super(sb);
 735                 if (error) {
 736                         fs_info(sdp, "GFS2: couldn't thaw filesystem: %d\n",
 737                                 error);
 738                         gfs2_assert_withdraw(sdp, 0);
 739                 }
 740                 if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
 741                         freeze_gh.gh_flags |= GL_NOCACHE;
 742                 gfs2_glock_dq_uninit(&freeze_gh);
 743         }
 744         deactivate_super(sb);
 745         clear_bit_unlock(SDF_FS_FROZEN, &sdp->sd_flags);
 746         wake_up_bit(&sdp->sd_flags, SDF_FS_FROZEN);
 747         return;
 748 }
 749
 750 /**
 751  * gfs2_freeze - prevent further writes to the filesystem
 752  * @sb: the VFS structure for the filesystem
 753  *
 754  */
 755
 756 static int gfs2_freeze(struct super_block *sb)
 757 {
 758         struct gfs2_sbd *sdp = sb->s_fs_info;
 759         int error = 0;
 760
 761         mutex_lock(&sdp->sd_freeze_mutex);
 762         if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN)
 763                 goto out;
 764
 765         for (;;) {
 766                 if (gfs2_withdrawn(sdp)) {
 767                         error = -EINVAL;
 768                         goto out;
 769                 }
 770
 771                 error = gfs2_lock_fs_check_clean(sdp);
 772                 if (!error)
 773                         break;
 774
 775                 if (error == -EBUSY)
 776                         fs_err(sdp, "waiting for recovery before freeze\n");
 777                 else if (error == -EIO) {
 778                         fs_err(sdp, "Fatal IO error: cannot freeze gfs2 due "
 779                                "to recovery error.\n");
 780                         goto out;
 781                 } else {
 782                         fs_err(sdp, "error freezing FS: %d\n", error);
 783                 }
 784                 fs_err(sdp, "retrying...\n");
 785                 msleep(1000);
 786         }
 787         set_bit(SDF_FS_FROZEN, &sdp->sd_flags);
 788 out:
 789         mutex_unlock(&sdp->sd_freeze_mutex);
 790         return error;
 791 }
 792
 793 /**
 794  * gfs2_unfreeze - reallow writes to the filesystem
 795  * @sb: the VFS structure for the filesystem
 796  *
 797  */
 798
 799 static int gfs2_unfreeze(struct super_block *sb)
 800 {
 801         struct gfs2_sbd *sdp = sb->s_fs_info;
 802
 803         mutex_lock(&sdp->sd_freeze_mutex);
 804         if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
 805             !gfs2_holder_initialized(&sdp->sd_freeze_gh)) {
 806                 mutex_unlock(&sdp->sd_freeze_mutex);
 807                 return 0;
 808         }
 809
 810         gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 811         mutex_unlock(&sdp->sd_freeze_mutex);
 812         return wait_on_bit(&sdp->sd_flags, SDF_FS_FROZEN, TASK_INTERRUPTIBLE);
 813 }
 814
 815 /**
 816  * statfs_fill - fill in the sg for a given RG
 817  * @rgd: the RG
 818  * @sc: the sc structure
 819  *
 820  * Returns: 0 on success, -ESTALE if the LVB is invalid
 821  */
 822
 823 static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
 824                             struct gfs2_statfs_change_host *sc)
 825 {
 826         gfs2_rgrp_verify(rgd);
 827         sc->sc_total += rgd->rd_data;
 828         sc->sc_free += rgd->rd_free;
 829         sc->sc_dinodes += rgd->rd_dinodes;
 830         return 0;
 831 }
 832
 833 /**
 834  * gfs2_statfs_slow - Stat a filesystem using asynchronous locking
 835  * @sdp: the filesystem
 836  * @sc: the sc info that will be returned
 837  *
 838  * Any error (other than a signal) will cause this routine to fall back
 839  * to the synchronous version.
 840  *
 841  * FIXME: This really shouldn't busy wait like this.
 842  *
 843  * Returns: errno
 844  */
 845
 846 static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 847 {
 848         struct gfs2_rgrpd *rgd_next;
 849         struct gfs2_holder *gha, *gh;
 850         unsigned int slots = 64;
 851         unsigned int x;
 852         int done;
 853         int error = 0, err;
 854
 855         memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
 856         gha = kmalloc_array(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
 857         if (!gha)
 858                 return -ENOMEM;
 859         for (x = 0; x < slots; x++)
 860                 gfs2_holder_mark_uninitialized(gha + x);
 861
 862         rgd_next = gfs2_rgrpd_get_first(sdp);
 863
 864         for (;;) {
 865                 done = 1;
 866
 867                 for (x = 0; x < slots; x++) {
 868                         gh = gha + x;
 869
 870                         if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) {
 871                                 err = gfs2_glock_wait(gh);
 872                                 if (err) {
 873                                         gfs2_holder_uninit(gh);
 874                                         error = err;
 875                                 } else {
 876                                         if (!error) {
 877                                                 struct gfs2_rgrpd *rgd =
 878                                                         gfs2_glock2rgrp(gh->gh_gl);
 879
 880                                                 error = statfs_slow_fill(rgd, sc);
 881                                         }
 882                                         gfs2_glock_dq_uninit(gh);
 883                                 }
 884                         }
 885
 886                         if (gfs2_holder_initialized(gh))
 887                                 done = 0;
 888                         else if (rgd_next && !error) {
 889                                 error = gfs2_glock_nq_init(rgd_next->rd_gl,
 890                                                            LM_ST_SHARED,
 891                                                            GL_ASYNC,
 892                                                            gh);
 893                                 rgd_next = gfs2_rgrpd_get_next(rgd_next);
 894                                 done = 0;
 895                         }
 896
 897                         if (signal_pending(current))
 898                                 error = -ERESTARTSYS;
 899                 }
 900
 901                 if (done)
 902                         break;
 903
 904                 yield();
 905         }
 906
 907         kfree(gha);
 908         return error;
 909 }
 910
 911 /**
 912  * gfs2_statfs_i - Do a statfs
 913  * @sdp: the filesystem
 914  * @sg: the sg structure
 915  *
 916  * Returns: errno
 917  */
 918
 919 static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
 920 {
 921         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 922         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 923
 924         spin_lock(&sdp->sd_statfs_spin);
 925
 926         *sc = *m_sc;
 927         sc->sc_total += l_sc->sc_total;
 928         sc->sc_free += l_sc->sc_free;
 929         sc->sc_dinodes += l_sc->sc_dinodes;
 930
 931         spin_unlock(&sdp->sd_statfs_spin);
 932
 933         if (sc->sc_free < 0)
 934                 sc->sc_free = 0;
 935         if (sc->sc_free > sc->sc_total)
 936                 sc->sc_free = sc->sc_total;
 937         if (sc->sc_dinodes < 0)
 938                 sc->sc_dinodes = 0;
 939
 940         return 0;
 941 }
 942
 943 /**
 944  * gfs2_statfs - Gather and return stats about the filesystem
 945  * @sb: The superblock
 946  * @statfsbuf: The buffer
 947  *
 948  * Returns: 0 on success or error code
 949  */
 950
 951 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 952 {
 953         struct super_block *sb = dentry->d_sb;
 954         struct gfs2_sbd *sdp = sb->s_fs_info;
 955         struct gfs2_statfs_change_host sc;
 956         int error;
 957
 958         error = gfs2_rindex_update(sdp);
 959         if (error)
 960                 return error;
 961
 962         if (gfs2_tune_get(sdp, gt_statfs_slow))
 963                 error = gfs2_statfs_slow(sdp, &sc);
 964         else
 965                 error = gfs2_statfs_i(sdp, &sc);
 966
 967         if (error)
 968                 return error;
 969
 970         buf->f_type = GFS2_MAGIC;
 971         buf->f_bsize = sdp->sd_sb.sb_bsize;
 972         buf->f_blocks = sc.sc_total;
 973         buf->f_bfree = sc.sc_free;
 974         buf->f_bavail = sc.sc_free;
 975         buf->f_files = sc.sc_dinodes + sc.sc_free;
 976         buf->f_ffree = sc.sc_free;
 977         buf->f_namelen = GFS2_FNAMESIZE;
 978
 979         return 0;
 980 }
 981
 982 /**
 983  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 984  * @inode: The inode to drop
 985  *
 986  * If we've received a callback on an iopen lock then it's because a
 987  * remote node tried to deallocate the inode but failed due to this node
 988  * still having the inode open. Here we mark the link count zero
 989  * since we know that it must have reached zero if the GLF_DEMOTE flag
 990  * is set on the iopen glock. If we didn't do a disk read since the
 991  * remote node removed the final link then we might otherwise miss
 992  * this event. This check ensures that this node will deallocate the
 993  * inode's blocks, or alternatively pass the baton on to another
 994  * node for later deallocation.
 995  */
 996
 997 static int gfs2_drop_inode(struct inode *inode)
 998 {
 999         struct gfs2_inode *ip = GFS2_I(inode);
1000
1001         if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) &&
1002             inode->i_nlink &&
1003             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1004                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1005                 if (test_bit(GLF_DEMOTE, &gl->gl_flags))
1006                         clear_nlink(inode);
1007         }
1008
1009         /*
1010          * When under memory pressure when an inode's link count has dropped to
1011          * zero, defer deleting the inode to the delete workqueue.  This avoids
1012          * calling into DLM under memory pressure, which can deadlock.
1013          */
1014         if (!inode->i_nlink &&
1015             unlikely(current->flags & PF_MEMALLOC) &&
1016             gfs2_holder_initialized(&ip->i_iopen_gh)) {
1017                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1018
1019                 gfs2_glock_hold(gl);
1020                 if (queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
1021                         gfs2_glock_queue_put(gl);
1022                 return false;
1023         }
1024
1025         return generic_drop_inode(inode);
1026 }
1027
1028 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
1029 {
1030         do {
1031                 if (d1 == d2)
1032                         return 1;
1033                 d1 = d1->d_parent;
1034         } while (!IS_ROOT(d1));
1035         return 0;
1036 }
1037
1038 /**
1039  * gfs2_show_options - Show mount options for /proc/mounts
1040  * @s: seq_file structure
1041  * @root: root of this (sub)tree
1042  *
1043  * Returns: 0 on success or error code
1044  */
1045
1046 static int gfs2_show_options(struct seq_file *s, struct dentry *root)
1047 {
1048         struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
1049         struct gfs2_args *args = &sdp->sd_args;
1050         int val;
1051
1052         if (is_ancestor(root, sdp->sd_master_dir))
1053                 seq_puts(s, ",meta");
1054         if (args->ar_lockproto[0])
1055                 seq_show_option(s, "lockproto", args->ar_lockproto);
1056         if (args->ar_locktable[0])
1057                 seq_show_option(s, "locktable", args->ar_locktable);
1058         if (args->ar_hostdata[0])
1059                 seq_show_option(s, "hostdata", args->ar_hostdata);
1060         if (args->ar_spectator)
1061                 seq_puts(s, ",spectator");
1062         if (args->ar_localflocks)
1063                 seq_puts(s, ",localflocks");
1064         if (args->ar_debug)
1065                 seq_puts(s, ",debug");
1066         if (args->ar_posix_acl)
1067                 seq_puts(s, ",acl");
1068         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
1069                 char *state;
1070                 switch (args->ar_quota) {
1071                 case GFS2_QUOTA_OFF:
1072                         state = "off";
1073                         break;
1074                 case GFS2_QUOTA_ACCOUNT:
1075                         state = "account";
1076                         break;
1077                 case GFS2_QUOTA_ON:
1078                         state = "on";
1079                         break;
1080                 default:
1081                         state = "unknown";
1082                         break;
1083                 }
1084                 seq_printf(s, ",quota=%s", state);
1085         }
1086         if (args->ar_suiddir)
1087                 seq_puts(s, ",suiddir");
1088         if (args->ar_data != GFS2_DATA_DEFAULT) {
1089                 char *state;
1090                 switch (args->ar_data) {
1091                 case GFS2_DATA_WRITEBACK:
1092                         state = "writeback";
1093                         break;
1094                 case GFS2_DATA_ORDERED:
1095                         state = "ordered";
1096                         break;
1097                 default:
1098                         state = "unknown";
1099                         break;
1100                 }
1101                 seq_printf(s, ",data=%s", state);
1102         }
1103         if (args->ar_discard)
1104                 seq_puts(s, ",discard");
1105         val = sdp->sd_tune.gt_logd_secs;
1106         if (val != 30)
1107                 seq_printf(s, ",commit=%d", val);
1108         val = sdp->sd_tune.gt_statfs_quantum;
1109         if (val != 30)
1110                 seq_printf(s, ",statfs_quantum=%d", val);
1111         else if (sdp->sd_tune.gt_statfs_slow)
1112                 seq_puts(s, ",statfs_quantum=0");
1113         val = sdp->sd_tune.gt_quota_quantum;
1114         if (val != 60)
1115                 seq_printf(s, ",quota_quantum=%d", val);
1116         if (args->ar_statfs_percent)
1117                 seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
1118         if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
1119                 const char *state;
1120
1121                 switch (args->ar_errors) {
1122                 case GFS2_ERRORS_WITHDRAW:
1123                         state = "withdraw";
1124                         break;
1125                 case GFS2_ERRORS_PANIC:
1126                         state = "panic";
1127                         break;
1128                 default:
1129                         state = "unknown";
1130                         break;
1131                 }
1132                 seq_printf(s, ",errors=%s", state);
1133         }
1134         if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
1135                 seq_puts(s, ",nobarrier");
1136         if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
1137                 seq_puts(s, ",demote_interface_used");
1138         if (args->ar_rgrplvb)
1139                 seq_puts(s, ",rgrplvb");
1140         if (args->ar_loccookie)
1141                 seq_puts(s, ",loccookie");
1142         return 0;
1143 }
1144
1145 static void gfs2_final_release_pages(struct gfs2_inode *ip)
1146 {
1147         struct inode *inode = &ip->i_inode;
1148         struct gfs2_glock *gl = ip->i_gl;
1149
1150         truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
1151         truncate_inode_pages(&inode->i_data, 0);
1152
1153         if (atomic_read(&gl->gl_revokes) == 0) {
1154                 clear_bit(GLF_LFLUSH, &gl->gl_flags);
1155                 clear_bit(GLF_DIRTY, &gl->gl_flags);
1156         }
1157 }
1158
1159 static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
1160 {
1161         struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
1162         struct gfs2_rgrpd *rgd;
1163         struct gfs2_holder gh;
1164         int error;
1165
1166         if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
1167                 gfs2_consist_inode(ip);
1168                 return -EIO;
1169         }
1170
1171         error = gfs2_rindex_update(sdp);
1172         if (error)
1173                 return error;
1174
1175         error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
1176         if (error)
1177                 return error;
1178
1179         rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
1180         if (!rgd) {
1181                 gfs2_consist_inode(ip);
1182                 error = -EIO;
1183                 goto out_qs;
1184         }
1185
1186         error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
1187         if (error)
1188                 goto out_qs;
1189
1190         error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
1191                                  sdp->sd_jdesc->jd_blocks);
1192         if (error)
1193                 goto out_rg_gunlock;
1194
1195         gfs2_free_di(rgd, ip);
1196
1197         gfs2_final_release_pages(ip);
1198
1199         gfs2_trans_end(sdp);
1200
1201 out_rg_gunlock:
1202         gfs2_glock_dq_uninit(&gh);
1203 out_qs:
1204         gfs2_quota_unhold(ip);
1205         return error;
1206 }
1207
1208 /**
1209  * gfs2_glock_put_eventually
1210  * @gl: The glock to put
1211  *
1212  * When under memory pressure, trigger a deferred glock put to make sure we
1213  * won't call into DLM and deadlock.  Otherwise, put the glock directly.
1214  */
1215
1216 static void gfs2_glock_put_eventually(struct gfs2_glock *gl)
1217 {
1218         if (current->flags & PF_MEMALLOC)
1219                 gfs2_glock_queue_put(gl);
1220         else
1221                 gfs2_glock_put(gl);
1222 }
1223
1224 /**
1225  * gfs2_evict_inode - Remove an inode from cache
1226  * @inode: The inode to evict
1227  *
1228  * There are three cases to consider:
1229  * 1. i_nlink == 0, we are final opener (and must deallocate)
1230  * 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
1231  * 3. i_nlink > 0
1232  *
1233  * If the fs is read only, then we have to treat all cases as per #3
1234  * since we are unable to do any deallocation. The inode will be
1235  * deallocated by the next read/write node to attempt an allocation
1236  * in the same resource group
1237  *
1238  * We have to (at the moment) hold the inodes main lock to cover
1239  * the gap between unlocking the shared lock on the iopen lock and
1240  * taking the exclusive lock. I'd rather do a shared -> exclusive
1241  * conversion on the iopen lock, but we can change that later. This
1242  * is safe, just less efficient.
1243  */
1244
1245 static void gfs2_evict_inode(struct inode *inode)
1246 {
1247         struct super_block *sb = inode->i_sb;
1248         struct gfs2_sbd *sdp = sb->s_fs_info;
1249         struct gfs2_inode *ip = GFS2_I(inode);
1250         struct gfs2_holder gh;
1251         struct address_space *metamapping;
1252         int error;
1253
1254         if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
1255                 clear_inode(inode);
1256                 return;
1257         }
1258
1259         if (inode->i_nlink || sb_rdonly(sb))
1260                 goto out;
1261
1262         if (test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
1263                 BUG_ON(!gfs2_glock_is_locked_by_me(ip->i_gl));
1264                 gfs2_holder_mark_uninitialized(&gh);
1265                 goto alloc_failed;
1266         }
1267
1268         /* Deletes should never happen under memory pressure anymore.  */
1269         if (WARN_ON_ONCE(current->flags & PF_MEMALLOC))
1270                 goto out;
1271
1272         /* Must not read inode block until block type has been verified */
1273         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
1274         if (unlikely(error)) {
1275                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1276                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1277                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1278                 goto out;
1279         }
1280
1281         error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
1282         if (error)
1283                 goto out_truncate;
1284
1285         if (test_bit(GIF_INVALID, &ip->i_flags)) {
1286                 error = gfs2_inode_refresh(ip);
1287                 if (error)
1288                         goto out_truncate;
1289         }
1290
1291         /*
1292          * The inode may have been recreated in the meantime.
1293          */
1294         if (inode->i_nlink)
1295                 goto out_truncate;
1296
1297 alloc_failed:
1298         if (gfs2_holder_initialized(&ip->i_iopen_gh) &&
1299             test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1300                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1301                 gfs2_glock_dq_wait(&ip->i_iopen_gh);
1302                 gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE,
1303                                    &ip->i_iopen_gh);
1304                 error = gfs2_glock_nq(&ip->i_iopen_gh);
1305                 if (error)
1306                         goto out_truncate;
1307         }
1308
1309         if (S_ISDIR(inode->i_mode) &&
1310             (ip->i_diskflags & GFS2_DIF_EXHASH)) {
1311                 error = gfs2_dir_exhash_dealloc(ip);
1312                 if (error)
1313                         goto out_unlock;
1314         }
1315
1316         if (ip->i_eattr) {
1317                 error = gfs2_ea_dealloc(ip);
1318                 if (error)
1319                         goto out_unlock;
1320         }
1321
1322         if (!gfs2_is_stuffed(ip)) {
1323                 error = gfs2_file_dealloc(ip);
1324                 if (error)
1325                         goto out_unlock;
1326         }
1327
1328         /* We're about to clear the bitmap for the dinode, but as soon as we
1329            do, gfs2_create_inode can create another inode at the same block
1330            location and try to set gl_object again. We clear gl_object here so
1331            that subsequent inode creates don't see an old gl_object. */
1332         glock_clear_object(ip->i_gl, ip);
1333         error = gfs2_dinode_dealloc(ip);
1334         goto out_unlock;
1335
1336 out_truncate:
1337         gfs2_log_flush(sdp, ip->i_gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
1338                        GFS2_LFC_EVICT_INODE);
1339         metamapping = gfs2_glock2aspace(ip->i_gl);
1340         if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
1341                 filemap_fdatawrite(metamapping);
1342                 filemap_fdatawait(metamapping);
1343         }
1344         write_inode_now(inode, 1);
1345         gfs2_ail_flush(ip->i_gl, 0);
1346
1347         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
1348         if (error)
1349                 goto out_unlock;
1350         /* Needs to be done before glock release & also in a transaction */
1351         truncate_inode_pages(&inode->i_data, 0);
1352         truncate_inode_pages(metamapping, 0);
1353         gfs2_trans_end(sdp);
1354
1355 out_unlock:
1356         if (gfs2_rs_active(&ip->i_res))
1357                 gfs2_rs_deltree(&ip->i_res);
1358
1359         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1360                 glock_clear_object(ip->i_iopen_gh.gh_gl, ip);
1361                 if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
1362                         ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1363                         gfs2_glock_dq(&ip->i_iopen_gh);
1364                 }
1365                 gfs2_holder_uninit(&ip->i_iopen_gh);
1366         }
1367         if (gfs2_holder_initialized(&gh)) {
1368                 glock_clear_object(ip->i_gl, ip);
1369                 gfs2_glock_dq_uninit(&gh);
1370         }
1371         if (error && error != GLR_TRYFAILED && error != -EROFS)
1372                 fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
1373 out:
1374         truncate_inode_pages_final(&inode->i_data);
1375         gfs2_rsqa_delete(ip, NULL);
1376         gfs2_ordered_del_inode(ip);
1377         clear_inode(inode);
1378         gfs2_dir_hash_inval(ip);
1379         glock_clear_object(ip->i_gl, ip);
1380         wait_on_bit_io(&ip->i_flags, GIF_GLOP_PENDING, TASK_UNINTERRUPTIBLE);
1381         gfs2_glock_add_to_lru(ip->i_gl);
1382         gfs2_glock_put_eventually(ip->i_gl);
1383         ip->i_gl = NULL;
1384         if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
1385                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
1386
1387                 glock_clear_object(gl, ip);
1388                 ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
1389                 gfs2_glock_hold(gl);
1390                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
1391                 gfs2_glock_put_eventually(gl);
1392         }
1393 }
1394
1395 static struct inode *gfs2_alloc_inode(struct super_block *sb)
1396 {
1397         struct gfs2_inode *ip;
1398
1399         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
1400         if (!ip)
1401                 return NULL;
1402         ip->i_flags = 0;
1403         ip->i_gl = NULL;
1404         memset(&ip->i_res, 0, sizeof(ip->i_res));
1405         RB_CLEAR_NODE(&ip->i_res.rs_node);
1406         ip->i_rahead = 0;
1407         return &ip->i_inode;
1408 }
1409
1410 static void gfs2_free_inode(struct inode *inode)
1411 {
1412         kmem_cache_free(gfs2_inode_cachep, GFS2_I(inode));
1413 }
1414
1415 const struct super_operations gfs2_super_ops = {
1416         .alloc_inode            = gfs2_alloc_inode,
1417         .free_inode             = gfs2_free_inode,
1418         .write_inode            = gfs2_write_inode,
1419         .dirty_inode            = gfs2_dirty_inode,
1420         .evict_inode            = gfs2_evict_inode,
1421         .put_super              = gfs2_put_super,
1422         .sync_fs                = gfs2_sync_fs,
1423         .freeze_super           = gfs2_freeze,
1424         .thaw_super             = gfs2_unfreeze,
1425         .statfs                 = gfs2_statfs,
1426         .drop_inode             = gfs2_drop_inode,
1427         .show_options           = gfs2_show_options,
1428 };
1429