fs/gfs2/ops_super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2008 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/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/lm_interface.h>
  23 #include <linux/time.h>
  24
  25 #include "gfs2.h"
  26 #include "incore.h"
  27 #include "glock.h"
  28 #include "inode.h"
  29 #include "log.h"
  30 #include "mount.h"
  31 #include "ops_super.h"
  32 #include "quota.h"
  33 #include "recovery.h"
  34 #include "rgrp.h"
  35 #include "super.h"
  36 #include "sys.h"
  37 #include "util.h"
  38 #include "trans.h"
  39 #include "dir.h"
  40 #include "eattr.h"
  41 #include "bmap.h"
  42 #include "meta_io.h"
  43
  44 /**
  45  * gfs2_write_inode - Make sure the inode is stable on the disk
  46  * @inode: The inode
  47  * @sync: synchronous write flag
  48  *
  49  * Returns: errno
  50  */
  51
  52 static int gfs2_write_inode(struct inode *inode, int sync)
  53 {
  54         struct gfs2_inode *ip = GFS2_I(inode);
  55         struct gfs2_sbd *sdp = GFS2_SB(inode);
  56         struct gfs2_holder gh;
  57         struct buffer_head *bh;
  58         struct timespec atime;
  59         struct gfs2_dinode *di;
  60         int ret = 0;
  61
  62         /* Check this is a "normal" inode, etc */
  63         if (!test_bit(GIF_USER, &ip->i_flags) ||
  64             (current->flags & PF_MEMALLOC))
  65                 return 0;
  66         ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
  67         if (ret)
  68                 goto do_flush;
  69         ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
  70         if (ret)
  71                 goto do_unlock;
  72         ret = gfs2_meta_inode_buffer(ip, &bh);
  73         if (ret == 0) {
  74                 di = (struct gfs2_dinode *)bh->b_data;
  75                 atime.tv_sec = be64_to_cpu(di->di_atime);
  76                 atime.tv_nsec = be32_to_cpu(di->di_atime_nsec);
  77                 if (timespec_compare(&inode->i_atime, &atime) > 0) {
  78                         gfs2_trans_add_bh(ip->i_gl, bh, 1);
  79                         gfs2_dinode_out(ip, bh->b_data);
  80                 }
  81                 brelse(bh);
  82         }
  83         gfs2_trans_end(sdp);
  84 do_unlock:
  85         gfs2_glock_dq_uninit(&gh);
  86 do_flush:
  87         if (sync != 0)
  88                 gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
  89         return ret;
  90 }
  91
  92 /**
  93  * gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
  94  * @sdp: the filesystem
  95  *
  96  * Returns: errno
  97  */
  98
  99 static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
 100 {
 101         struct gfs2_holder t_gh;
 102         int error;
 103
 104         gfs2_quota_sync(sdp);
 105         gfs2_statfs_sync(sdp);
 106
 107         error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED, GL_NOCACHE,
 108                                    &t_gh);
 109         if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 110                 return error;
 111
 112         gfs2_meta_syncfs(sdp);
 113         gfs2_log_shutdown(sdp);
 114
 115         clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
 116
 117         if (t_gh.gh_gl)
 118                 gfs2_glock_dq_uninit(&t_gh);
 119
 120         gfs2_quota_cleanup(sdp);
 121
 122         return error;
 123 }
 124
 125 /**
 126  * gfs2_put_super - Unmount the filesystem
 127  * @sb: The VFS superblock
 128  *
 129  */
 130
 131 static void gfs2_put_super(struct super_block *sb)
 132 {
 133         struct gfs2_sbd *sdp = sb->s_fs_info;
 134         int error;
 135
 136         /*  Unfreeze the filesystem, if we need to  */
 137
 138         mutex_lock(&sdp->sd_freeze_lock);
 139         if (sdp->sd_freeze_count)
 140                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
 141         mutex_unlock(&sdp->sd_freeze_lock);
 142
 143         kthread_stop(sdp->sd_quotad_process);
 144         kthread_stop(sdp->sd_logd_process);
 145         kthread_stop(sdp->sd_recoverd_process);
 146         while (sdp->sd_glockd_num--)
 147                 kthread_stop(sdp->sd_glockd_process[sdp->sd_glockd_num]);
 148
 149         if (!(sb->s_flags & MS_RDONLY)) {
 150                 error = gfs2_make_fs_ro(sdp);
 151                 if (error)
 152                         gfs2_io_error(sdp);
 153         }
 154         /*  At this point, we're through modifying the disk  */
 155
 156         /*  Release stuff  */
 157
 158         iput(sdp->sd_jindex);
 159         iput(sdp->sd_inum_inode);
 160         iput(sdp->sd_statfs_inode);
 161         iput(sdp->sd_rindex);
 162         iput(sdp->sd_quota_inode);
 163
 164         gfs2_glock_put(sdp->sd_rename_gl);
 165         gfs2_glock_put(sdp->sd_trans_gl);
 166
 167         if (!sdp->sd_args.ar_spectator) {
 168                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 169                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 170                 gfs2_glock_dq_uninit(&sdp->sd_ir_gh);
 171                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 172                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 173                 iput(sdp->sd_ir_inode);
 174                 iput(sdp->sd_sc_inode);
 175                 iput(sdp->sd_qc_inode);
 176         }
 177
 178         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 179         gfs2_clear_rgrpd(sdp);
 180         gfs2_jindex_free(sdp);
 181         /*  Take apart glock structures and buffer lists  */
 182         gfs2_gl_hash_clear(sdp);
 183         /*  Unmount the locking protocol  */
 184         gfs2_lm_unmount(sdp);
 185
 186         /*  At this point, we're through participating in the lockspace  */
 187         gfs2_sys_fs_del(sdp);
 188         kfree(sdp);
 189 }
 190
 191 /**
 192  * gfs2_write_super
 193  * @sb: the superblock
 194  *
 195  */
 196
 197 static void gfs2_write_super(struct super_block *sb)
 198 {
 199         sb->s_dirt = 0;
 200 }
 201
 202 /**
 203  * gfs2_sync_fs - sync the filesystem
 204  * @sb: the superblock
 205  *
 206  * Flushes the log to disk.
 207  */
 208
 209 static int gfs2_sync_fs(struct super_block *sb, int wait)
 210 {
 211         sb->s_dirt = 0;
 212         if (wait && sb->s_fs_info)
 213                 gfs2_log_flush(sb->s_fs_info, NULL);
 214         return 0;
 215 }
 216
 217 /**
 218  * gfs2_write_super_lockfs - prevent further writes to the filesystem
 219  * @sb: the VFS structure for the filesystem
 220  *
 221  */
 222
 223 static void gfs2_write_super_lockfs(struct super_block *sb)
 224 {
 225         struct gfs2_sbd *sdp = sb->s_fs_info;
 226         int error;
 227
 228         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 229                 return;
 230
 231         for (;;) {
 232                 error = gfs2_freeze_fs(sdp);
 233                 if (!error)
 234                         break;
 235
 236                 switch (error) {
 237                 case -EBUSY:
 238                         fs_err(sdp, "waiting for recovery before freeze\n");
 239                         break;
 240
 241                 default:
 242                         fs_err(sdp, "error freezing FS: %d\n", error);
 243                         break;
 244                 }
 245
 246                 fs_err(sdp, "retrying...\n");
 247                 msleep(1000);
 248         }
 249 }
 250
 251 /**
 252  * gfs2_unlockfs - reallow writes to the filesystem
 253  * @sb: the VFS structure for the filesystem
 254  *
 255  */
 256
 257 static void gfs2_unlockfs(struct super_block *sb)
 258 {
 259         gfs2_unfreeze_fs(sb->s_fs_info);
 260 }
 261
 262 /**
 263  * gfs2_statfs - Gather and return stats about the filesystem
 264  * @sb: The superblock
 265  * @statfsbuf: The buffer
 266  *
 267  * Returns: 0 on success or error code
 268  */
 269
 270 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 271 {
 272         struct super_block *sb = dentry->d_inode->i_sb;
 273         struct gfs2_sbd *sdp = sb->s_fs_info;
 274         struct gfs2_statfs_change_host sc;
 275         int error;
 276
 277         if (gfs2_tune_get(sdp, gt_statfs_slow))
 278                 error = gfs2_statfs_slow(sdp, &sc);
 279         else
 280                 error = gfs2_statfs_i(sdp, &sc);
 281
 282         if (error)
 283                 return error;
 284
 285         buf->f_type = GFS2_MAGIC;
 286         buf->f_bsize = sdp->sd_sb.sb_bsize;
 287         buf->f_blocks = sc.sc_total;
 288         buf->f_bfree = sc.sc_free;
 289         buf->f_bavail = sc.sc_free;
 290         buf->f_files = sc.sc_dinodes + sc.sc_free;
 291         buf->f_ffree = sc.sc_free;
 292         buf->f_namelen = GFS2_FNAMESIZE;
 293
 294         return 0;
 295 }
 296
 297 /**
 298  * gfs2_remount_fs - called when the FS is remounted
 299  * @sb:  the filesystem
 300  * @flags:  the remount flags
 301  * @data:  extra data passed in (not used right now)
 302  *
 303  * Returns: errno
 304  */
 305
 306 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
 307 {
 308         struct gfs2_sbd *sdp = sb->s_fs_info;
 309         int error;
 310
 311         error = gfs2_mount_args(sdp, data, 1);
 312         if (error)
 313                 return error;
 314
 315         if (sdp->sd_args.ar_spectator)
 316                 *flags |= MS_RDONLY;
 317         else {
 318                 if (*flags & MS_RDONLY) {
 319                         if (!(sb->s_flags & MS_RDONLY))
 320                                 error = gfs2_make_fs_ro(sdp);
 321                 } else if (!(*flags & MS_RDONLY) &&
 322                            (sb->s_flags & MS_RDONLY)) {
 323                         error = gfs2_make_fs_rw(sdp);
 324                 }
 325         }
 326
 327         return error;
 328 }
 329
 330 /**
 331  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 332  * @inode: The inode to drop
 333  *
 334  * If we've received a callback on an iopen lock then its because a
 335  * remote node tried to deallocate the inode but failed due to this node
 336  * still having the inode open. Here we mark the link count zero
 337  * since we know that it must have reached zero if the GLF_DEMOTE flag
 338  * is set on the iopen glock. If we didn't do a disk read since the
 339  * remote node removed the final link then we might otherwise miss
 340  * this event. This check ensures that this node will deallocate the
 341  * inode's blocks, or alternatively pass the baton on to another
 342  * node for later deallocation.
 343  */
 344
 345 static void gfs2_drop_inode(struct inode *inode)
 346 {
 347         struct gfs2_inode *ip = GFS2_I(inode);
 348
 349         if (test_bit(GIF_USER, &ip->i_flags) && inode->i_nlink) {
 350                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 351                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
 352                         clear_nlink(inode);
 353         }
 354         generic_drop_inode(inode);
 355 }
 356
 357 /**
 358  * gfs2_clear_inode - Deallocate an inode when VFS is done with it
 359  * @inode: The VFS inode
 360  *
 361  */
 362
 363 static void gfs2_clear_inode(struct inode *inode)
 364 {
 365         struct gfs2_inode *ip = GFS2_I(inode);
 366
 367         /* This tells us its a "real" inode and not one which only
 368          * serves to contain an address space (see rgrp.c, meta_io.c)
 369          * which therefore doesn't have its own glocks.
 370          */
 371         if (test_bit(GIF_USER, &ip->i_flags)) {
 372                 ip->i_gl->gl_object = NULL;
 373                 gfs2_glock_schedule_for_reclaim(ip->i_gl);
 374                 gfs2_glock_put(ip->i_gl);
 375                 ip->i_gl = NULL;
 376                 if (ip->i_iopen_gh.gh_gl) {
 377                         ip->i_iopen_gh.gh_gl->gl_object = NULL;
 378                         gfs2_glock_dq_uninit(&ip->i_iopen_gh);
 379                 }
 380         }
 381 }
 382
 383 static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
 384 {
 385         do {
 386                 if (d1 == d2)
 387                         return 1;
 388                 d1 = d1->d_parent;
 389         } while (!IS_ROOT(d1));
 390         return 0;
 391 }
 392
 393 /**
 394  * gfs2_show_options - Show mount options for /proc/mounts
 395  * @s: seq_file structure
 396  * @mnt: vfsmount
 397  *
 398  * Returns: 0 on success or error code
 399  */
 400
 401 static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
 402 {
 403         struct gfs2_sbd *sdp = mnt->mnt_sb->s_fs_info;
 404         struct gfs2_args *args = &sdp->sd_args;
 405
 406         if (is_ancestor(mnt->mnt_root, sdp->sd_master_dir))
 407                 seq_printf(s, ",meta");
 408         if (args->ar_lockproto[0])
 409                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
 410         if (args->ar_locktable[0])
 411                 seq_printf(s, ",locktable=%s", args->ar_locktable);
 412         if (args->ar_hostdata[0])
 413                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
 414         if (args->ar_spectator)
 415                 seq_printf(s, ",spectator");
 416         if (args->ar_ignore_local_fs)
 417                 seq_printf(s, ",ignore_local_fs");
 418         if (args->ar_localflocks)
 419                 seq_printf(s, ",localflocks");
 420         if (args->ar_localcaching)
 421                 seq_printf(s, ",localcaching");
 422         if (args->ar_debug)
 423                 seq_printf(s, ",debug");
 424         if (args->ar_upgrade)
 425                 seq_printf(s, ",upgrade");
 426         if (args->ar_num_glockd != GFS2_GLOCKD_DEFAULT)
 427                 seq_printf(s, ",num_glockd=%u", args->ar_num_glockd);
 428         if (args->ar_posix_acl)
 429                 seq_printf(s, ",acl");
 430         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
 431                 char *state;
 432                 switch (args->ar_quota) {
 433                 case GFS2_QUOTA_OFF:
 434                         state = "off";
 435                         break;
 436                 case GFS2_QUOTA_ACCOUNT:
 437                         state = "account";
 438                         break;
 439                 case GFS2_QUOTA_ON:
 440                         state = "on";
 441                         break;
 442                 default:
 443                         state = "unknown";
 444                         break;
 445                 }
 446                 seq_printf(s, ",quota=%s", state);
 447         }
 448         if (args->ar_suiddir)
 449                 seq_printf(s, ",suiddir");
 450         if (args->ar_data != GFS2_DATA_DEFAULT) {
 451                 char *state;
 452                 switch (args->ar_data) {
 453                 case GFS2_DATA_WRITEBACK:
 454                         state = "writeback";
 455                         break;
 456                 case GFS2_DATA_ORDERED:
 457                         state = "ordered";
 458                         break;
 459                 default:
 460                         state = "unknown";
 461                         break;
 462                 }
 463                 seq_printf(s, ",data=%s", state);
 464         }
 465
 466         return 0;
 467 }
 468
 469 /*
 470  * We have to (at the moment) hold the inodes main lock to cover
 471  * the gap between unlocking the shared lock on the iopen lock and
 472  * taking the exclusive lock. I'd rather do a shared -> exclusive
 473  * conversion on the iopen lock, but we can change that later. This
 474  * is safe, just less efficient.
 475  */
 476
 477 static void gfs2_delete_inode(struct inode *inode)
 478 {
 479         struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
 480         struct gfs2_inode *ip = GFS2_I(inode);
 481         struct gfs2_holder gh;
 482         int error;
 483
 484         if (!test_bit(GIF_USER, &ip->i_flags))
 485                 goto out;
 486
 487         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 488         if (unlikely(error)) {
 489                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
 490                 goto out;
 491         }
 492
 493         gfs2_glock_dq_wait(&ip->i_iopen_gh);
 494         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
 495         error = gfs2_glock_nq(&ip->i_iopen_gh);
 496         if (error)
 497                 goto out_uninit;
 498
 499         if (S_ISDIR(inode->i_mode) &&
 500             (ip->i_di.di_flags & GFS2_DIF_EXHASH)) {
 501                 error = gfs2_dir_exhash_dealloc(ip);
 502                 if (error)
 503                         goto out_unlock;
 504         }
 505
 506         if (ip->i_di.di_eattr) {
 507                 error = gfs2_ea_dealloc(ip);
 508                 if (error)
 509                         goto out_unlock;
 510         }
 511
 512         if (!gfs2_is_stuffed(ip)) {
 513                 error = gfs2_file_dealloc(ip);
 514                 if (error)
 515                         goto out_unlock;
 516         }
 517
 518         error = gfs2_dinode_dealloc(ip);
 519         if (error)
 520                 goto out_unlock;
 521
 522         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
 523         if (error)
 524                 goto out_unlock;
 525         /* Needs to be done before glock release & also in a transaction */
 526         truncate_inode_pages(&inode->i_data, 0);
 527         gfs2_trans_end(sdp);
 528
 529 out_unlock:
 530         gfs2_glock_dq(&ip->i_iopen_gh);
 531 out_uninit:
 532         gfs2_holder_uninit(&ip->i_iopen_gh);
 533         gfs2_glock_dq_uninit(&gh);
 534         if (error && error != GLR_TRYFAILED)
 535                 fs_warn(sdp, "gfs2_delete_inode: %d\n", error);
 536 out:
 537         truncate_inode_pages(&inode->i_data, 0);
 538         clear_inode(inode);
 539 }
 540
 541 static struct inode *gfs2_alloc_inode(struct super_block *sb)
 542 {
 543         struct gfs2_inode *ip;
 544
 545         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
 546         if (ip) {
 547                 ip->i_flags = 0;
 548                 ip->i_gl = NULL;
 549         }
 550         return &ip->i_inode;
 551 }
 552
 553 static void gfs2_destroy_inode(struct inode *inode)
 554 {
 555         kmem_cache_free(gfs2_inode_cachep, inode);
 556 }
 557
 558 const struct super_operations gfs2_super_ops = {
 559         .alloc_inode            = gfs2_alloc_inode,
 560         .destroy_inode          = gfs2_destroy_inode,
 561         .write_inode            = gfs2_write_inode,
 562         .delete_inode           = gfs2_delete_inode,
 563         .put_super              = gfs2_put_super,
 564         .write_super            = gfs2_write_super,
 565         .sync_fs                = gfs2_sync_fs,
 566         .write_super_lockfs     = gfs2_write_super_lockfs,
 567         .unlockfs               = gfs2_unlockfs,
 568         .statfs                 = gfs2_statfs,
 569         .remount_fs             = gfs2_remount_fs,
 570         .clear_inode            = gfs2_clear_inode,
 571         .drop_inode             = gfs2_drop_inode,
 572         .show_options           = gfs2_show_options,
 573 };
 574