git.oblomov.eu Git - linux-2.6/blob - fs/gfs2/super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2007 Red Hat, Inc.  All rights reserved.
   4  *
   5  * This copyrighted material is made available to anyone wishing to use,
   6  * modify, copy, or redistribute it subject to the terms and conditions
   7  * of the GNU General Public License version 2.
   8  */
   9
  10 #include <linux/sched.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/crc32.h>
  16 #include <linux/gfs2_ondisk.h>
  17 #include <linux/bio.h>
  18
  19 #include "gfs2.h"
  20 #include "incore.h"
  21 #include "bmap.h"
  22 #include "dir.h"
  23 #include "glock.h"
  24 #include "glops.h"
  25 #include "inode.h"
  26 #include "log.h"
  27 #include "meta_io.h"
  28 #include "quota.h"
  29 #include "recovery.h"
  30 #include "rgrp.h"
  31 #include "super.h"
  32 #include "trans.h"
  33 #include "util.h"
  34
  35 /**
  36  * gfs2_jindex_free - Clear all the journal index information
  37  * @sdp: The GFS2 superblock
  38  *
  39  */
  40
  41 void gfs2_jindex_free(struct gfs2_sbd *sdp)
  42 {
  43         struct list_head list, *head;
  44         struct gfs2_jdesc *jd;
  45         struct gfs2_journal_extent *jext;
  46
  47         spin_lock(&sdp->sd_jindex_spin);
  48         list_add(&list, &sdp->sd_jindex_list);
  49         list_del_init(&sdp->sd_jindex_list);
  50         sdp->sd_journals = 0;
  51         spin_unlock(&sdp->sd_jindex_spin);
  52
  53         while (!list_empty(&list)) {
  54                 jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
  55                 head = &jd->extent_list;
  56                 while (!list_empty(head)) {
  57                         jext = list_entry(head->next,
  58                                           struct gfs2_journal_extent,
  59                                           extent_list);
  60                         list_del(&jext->extent_list);
  61                         kfree(jext);
  62                 }
  63                 list_del(&jd->jd_list);
  64                 iput(jd->jd_inode);
  65                 kfree(jd);
  66         }
  67 }
  68
  69 static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
  70 {
  71         struct gfs2_jdesc *jd;
  72         int found = 0;
  73
  74         list_for_each_entry(jd, head, jd_list) {
  75                 if (jd->jd_jid == jid) {
  76                         found = 1;
  77                         break;
  78                 }
  79         }
  80
  81         if (!found)
  82                 jd = NULL;
  83
  84         return jd;
  85 }
  86
  87 struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
  88 {
  89         struct gfs2_jdesc *jd;
  90
  91         spin_lock(&sdp->sd_jindex_spin);
  92         jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
  93         spin_unlock(&sdp->sd_jindex_spin);
  94
  95         return jd;
  96 }
  97
  98 int gfs2_jdesc_check(struct gfs2_jdesc *jd)
  99 {
 100         struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
 101         struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
 102         int ar;
 103         int error;
 104
 105         if (ip->i_disksize < (8 << 20) || ip->i_disksize > (1 << 30) ||
 106             (ip->i_disksize & (sdp->sd_sb.sb_bsize - 1))) {
 107                 gfs2_consist_inode(ip);
 108                 return -EIO;
 109         }
 110         jd->jd_blocks = ip->i_disksize >> sdp->sd_sb.sb_bsize_shift;
 111
 112         error = gfs2_write_alloc_required(ip, 0, ip->i_disksize, &ar);
 113         if (!error && ar) {
 114                 gfs2_consist_inode(ip);
 115                 error = -EIO;
 116         }
 117
 118         return error;
 119 }
 120
 121 /**
 122  * gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
 123  * @sdp: the filesystem
 124  *
 125  * Returns: errno
 126  */
 127
 128 int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
 129 {
 130         struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
 131         struct gfs2_glock *j_gl = ip->i_gl;
 132         struct gfs2_holder t_gh;
 133         struct gfs2_log_header_host head;
 134         int error;
 135
 136         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, 0, &t_gh);
 137         if (error)
 138                 return error;
 139
 140         j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
 141
 142         error = gfs2_find_jhead(sdp->sd_jdesc, &head);
 143         if (error)
 144                 goto fail;
 145
 146         if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 147                 gfs2_consist(sdp);
 148                 error = -EIO;
 149                 goto fail;
 150         }
 151
 152         /*  Initialize some head of the log stuff  */
 153         sdp->sd_log_sequence = head.lh_sequence + 1;
 154         gfs2_log_pointers_init(sdp, head.lh_blkno);
 155
 156         error = gfs2_quota_init(sdp);
 157         if (error)
 158                 goto fail;
 159
 160         set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 161
 162         gfs2_glock_dq_uninit(&t_gh);
 163
 164         return 0;
 165
 166 fail:
 167         t_gh.gh_flags |= GL_NOCACHE;
 168         gfs2_glock_dq_uninit(&t_gh);
 169
 170         return error;
 171 }
 172
 173 static void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
 174 {
 175         const struct gfs2_statfs_change *str = buf;
 176
 177         sc->sc_total = be64_to_cpu(str->sc_total);
 178         sc->sc_free = be64_to_cpu(str->sc_free);
 179         sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
 180 }
 181
 182 static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
 183 {
 184         struct gfs2_statfs_change *str = buf;
 185
 186         str->sc_total = cpu_to_be64(sc->sc_total);
 187         str->sc_free = cpu_to_be64(sc->sc_free);
 188         str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
 189 }
 190
 191 int gfs2_statfs_init(struct gfs2_sbd *sdp)
 192 {
 193         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 194         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 195         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 196         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 197         struct buffer_head *m_bh, *l_bh;
 198         struct gfs2_holder gh;
 199         int error;
 200
 201         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 202                                    &gh);
 203         if (error)
 204                 return error;
 205
 206         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 207         if (error)
 208                 goto out;
 209
 210         if (sdp->sd_args.ar_spectator) {
 211                 spin_lock(&sdp->sd_statfs_spin);
 212                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 213                                       sizeof(struct gfs2_dinode));
 214                 spin_unlock(&sdp->sd_statfs_spin);
 215         } else {
 216                 error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 217                 if (error)
 218                         goto out_m_bh;
 219
 220                 spin_lock(&sdp->sd_statfs_spin);
 221                 gfs2_statfs_change_in(m_sc, m_bh->b_data +
 222                                       sizeof(struct gfs2_dinode));
 223                 gfs2_statfs_change_in(l_sc, l_bh->b_data +
 224                                       sizeof(struct gfs2_dinode));
 225                 spin_unlock(&sdp->sd_statfs_spin);
 226
 227                 brelse(l_bh);
 228         }
 229
 230 out_m_bh:
 231         brelse(m_bh);
 232 out:
 233         gfs2_glock_dq_uninit(&gh);
 234         return 0;
 235 }
 236
 237 void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
 238                         s64 dinodes)
 239 {
 240         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 241         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 242         struct buffer_head *l_bh;
 243         int error;
 244
 245         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 246         if (error)
 247                 return;
 248
 249         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 250
 251         spin_lock(&sdp->sd_statfs_spin);
 252         l_sc->sc_total += total;
 253         l_sc->sc_free += free;
 254         l_sc->sc_dinodes += dinodes;
 255         gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
 256         spin_unlock(&sdp->sd_statfs_spin);
 257
 258         brelse(l_bh);
 259 }
 260
 261 int gfs2_statfs_sync(struct gfs2_sbd *sdp)
 262 {
 263         struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
 264         struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
 265         struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
 266         struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
 267         struct gfs2_holder gh;
 268         struct buffer_head *m_bh, *l_bh;
 269         int error;
 270
 271         error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
 272                                    &gh);
 273         if (error)
 274                 return error;
 275
 276         error = gfs2_meta_inode_buffer(m_ip, &m_bh);
 277         if (error)
 278                 goto out;
 279
 280         spin_lock(&sdp->sd_statfs_spin);
 281         gfs2_statfs_change_in(m_sc, m_bh->b_data +
 282                               sizeof(struct gfs2_dinode));
 283         if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
 284                 spin_unlock(&sdp->sd_statfs_spin);
 285                 goto out_bh;
 286         }
 287         spin_unlock(&sdp->sd_statfs_spin);
 288
 289         error = gfs2_meta_inode_buffer(l_ip, &l_bh);
 290         if (error)
 291                 goto out_bh;
 292
 293         error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
 294         if (error)
 295                 goto out_bh2;
 296
 297         gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
 298
 299         spin_lock(&sdp->sd_statfs_spin);
 300         m_sc->sc_total += l_sc->sc_total;
 301         m_sc->sc_free += l_sc->sc_free;
 302         m_sc->sc_dinodes += l_sc->sc_dinodes;
 303         memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
 304         memset(l_bh->b_data + sizeof(struct gfs2_dinode),
 305                0, sizeof(struct gfs2_statfs_change));
 306         spin_unlock(&sdp->sd_statfs_spin);
 307
 308         gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
 309         gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
 310
 311         gfs2_trans_end(sdp);
 312
 313 out_bh2:
 314         brelse(l_bh);
 315 out_bh:
 316         brelse(m_bh);
 317 out:
 318         gfs2_glock_dq_uninit(&gh);
 319         return error;
 320 }
 321
 322 struct lfcc {
 323         struct list_head list;
 324         struct gfs2_holder gh;
 325 };
 326
 327 /**
 328  * gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
 329  *                            journals are clean
 330  * @sdp: the file system
 331  * @state: the state to put the transaction lock into
 332  * @t_gh: the hold on the transaction lock
 333  *
 334  * Returns: errno
 335  */
 336
 337 static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
 338                                     struct gfs2_holder *t_gh)
 339 {
 340         struct gfs2_inode *ip;
 341         struct gfs2_jdesc *jd;
 342         struct lfcc *lfcc;
 343         LIST_HEAD(list);
 344         struct gfs2_log_header_host lh;
 345         int error;
 346
 347         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 348                 lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
 349                 if (!lfcc) {
 350                         error = -ENOMEM;
 351                         goto out;
 352                 }
 353                 ip = GFS2_I(jd->jd_inode);
 354                 error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
 355                 if (error) {
 356                         kfree(lfcc);
 357                         goto out;
 358                 }
 359                 list_add(&lfcc->list, &list);
 360         }
 361
 362         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
 363                                    GL_NOCACHE, t_gh);
 364
 365         list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
 366                 error = gfs2_jdesc_check(jd);
 367                 if (error)
 368                         break;
 369                 error = gfs2_find_jhead(jd, &lh);
 370                 if (error)
 371                         break;
 372                 if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
 373                         error = -EBUSY;
 374                         break;
 375                 }
 376         }
 377
 378         if (error)
 379                 gfs2_glock_dq_uninit(t_gh);
 380
 381 out:
 382         while (!list_empty(&list)) {
 383                 lfcc = list_entry(list.next, struct lfcc, list);
 384                 list_del(&lfcc->list);
 385                 gfs2_glock_dq_uninit(&lfcc->gh);
 386                 kfree(lfcc);
 387         }
 388         return error;
 389 }
 390
 391 /**
 392  * gfs2_freeze_fs - freezes the file system
 393  * @sdp: the file system
 394  *
 395  * This function flushes data and meta data for all machines by
 396  * aquiring the transaction log exclusively.  All journals are
 397  * ensured to be in a clean state as well.
 398  *
 399  * Returns: errno
 400  */
 401
 402 int gfs2_freeze_fs(struct gfs2_sbd *sdp)
 403 {
 404         int error = 0;
 405
 406         mutex_lock(&sdp->sd_freeze_lock);
 407
 408         if (!sdp->sd_freeze_count++) {
 409                 error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
 410                 if (error)
 411                         sdp->sd_freeze_count--;
 412         }
 413
 414         mutex_unlock(&sdp->sd_freeze_lock);
 415
 416         return error;
 417 }
 418
 419 /**
 420  * gfs2_unfreeze_fs - unfreezes the file system
 421  * @sdp: the file system
 422  *
 423  * This function allows the file system to proceed by unlocking
 424  * the exclusively held transaction lock.  Other GFS2 nodes are
 425  * now free to acquire the lock shared and go on with their lives.
 426  *
 427  */
 428
 429 void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
 430 {
 431         mutex_lock(&sdp->sd_freeze_lock);
 432
 433         if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
 434                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 435
 436         mutex_unlock(&sdp->sd_freeze_lock);
 437 }
 438