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