fs/gfs2/ops_super.c

   1 /*
   2  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
   3  * Copyright (C) 2004-2006 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
  24 #include "gfs2.h"
  25 #include "incore.h"
  26 #include "glock.h"
  27 #include "inode.h"
  28 #include "lm.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
  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
  55         /* Check this is a "normal" inode */
  56         if (inode->i_private) {
  57                 if (current->flags & PF_MEMALLOC)
  58                         return 0;
  59                 if (sync)
  60                         gfs2_log_flush(GFS2_SB(inode), ip->i_gl);
  61         }
  62
  63         return 0;
  64 }
  65
  66 /**
  67  * gfs2_put_super - Unmount the filesystem
  68  * @sb: The VFS superblock
  69  *
  70  */
  71
  72 static void gfs2_put_super(struct super_block *sb)
  73 {
  74         struct gfs2_sbd *sdp = sb->s_fs_info;
  75         int error;
  76
  77         if (!sdp)
  78                 return;
  79
  80         if (!strncmp(sb->s_type->name, "gfs2meta", 8))
  81                 return; /* Nothing to do */
  82
  83         /*  Unfreeze the filesystem, if we need to  */
  84
  85         mutex_lock(&sdp->sd_freeze_lock);
  86         if (sdp->sd_freeze_count)
  87                 gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
  88         mutex_unlock(&sdp->sd_freeze_lock);
  89
  90         kthread_stop(sdp->sd_quotad_process);
  91         kthread_stop(sdp->sd_logd_process);
  92         kthread_stop(sdp->sd_recoverd_process);
  93         while (sdp->sd_glockd_num--)
  94                 kthread_stop(sdp->sd_glockd_process[sdp->sd_glockd_num]);
  95
  96         if (!(sb->s_flags & MS_RDONLY)) {
  97                 error = gfs2_make_fs_ro(sdp);
  98                 if (error)
  99                         gfs2_io_error(sdp);
 100         }
 101         /*  At this point, we're through modifying the disk  */
 102
 103         /*  Release stuff  */
 104
 105         iput(sdp->sd_master_dir);
 106         iput(sdp->sd_jindex);
 107         iput(sdp->sd_inum_inode);
 108         iput(sdp->sd_statfs_inode);
 109         iput(sdp->sd_rindex);
 110         iput(sdp->sd_quota_inode);
 111
 112         gfs2_glock_put(sdp->sd_rename_gl);
 113         gfs2_glock_put(sdp->sd_trans_gl);
 114
 115         if (!sdp->sd_args.ar_spectator) {
 116                 gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
 117                 gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
 118                 gfs2_glock_dq_uninit(&sdp->sd_ir_gh);
 119                 gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
 120                 gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
 121                 iput(sdp->sd_ir_inode);
 122                 iput(sdp->sd_sc_inode);
 123                 iput(sdp->sd_qc_inode);
 124         }
 125
 126         gfs2_glock_dq_uninit(&sdp->sd_live_gh);
 127         gfs2_clear_rgrpd(sdp);
 128         gfs2_jindex_free(sdp);
 129         /*  Take apart glock structures and buffer lists  */
 130         gfs2_gl_hash_clear(sdp, WAIT);
 131         /*  Unmount the locking protocol  */
 132         gfs2_lm_unmount(sdp);
 133
 134         /*  At this point, we're through participating in the lockspace  */
 135         gfs2_sys_fs_del(sdp);
 136         kfree(sdp);
 137 }
 138
 139 /**
 140  * gfs2_write_super
 141  * @sb: the superblock
 142  *
 143  */
 144
 145 static void gfs2_write_super(struct super_block *sb)
 146 {
 147         sb->s_dirt = 0;
 148 }
 149
 150 /**
 151  * gfs2_sync_fs - sync the filesystem
 152  * @sb: the superblock
 153  *
 154  * Flushes the log to disk.
 155  */
 156 static int gfs2_sync_fs(struct super_block *sb, int wait)
 157 {
 158         sb->s_dirt = 0;
 159         if (wait)
 160                 gfs2_log_flush(sb->s_fs_info, NULL);
 161         return 0;
 162 }
 163
 164 /**
 165  * gfs2_write_super_lockfs - prevent further writes to the filesystem
 166  * @sb: the VFS structure for the filesystem
 167  *
 168  */
 169
 170 static void gfs2_write_super_lockfs(struct super_block *sb)
 171 {
 172         struct gfs2_sbd *sdp = sb->s_fs_info;
 173         int error;
 174
 175         if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
 176                 return;
 177
 178         for (;;) {
 179                 error = gfs2_freeze_fs(sdp);
 180                 if (!error)
 181                         break;
 182
 183                 switch (error) {
 184                 case -EBUSY:
 185                         fs_err(sdp, "waiting for recovery before freeze\n");
 186                         break;
 187
 188                 default:
 189                         fs_err(sdp, "error freezing FS: %d\n", error);
 190                         break;
 191                 }
 192
 193                 fs_err(sdp, "retrying...\n");
 194                 msleep(1000);
 195         }
 196 }
 197
 198 /**
 199  * gfs2_unlockfs - reallow writes to the filesystem
 200  * @sb: the VFS structure for the filesystem
 201  *
 202  */
 203
 204 static void gfs2_unlockfs(struct super_block *sb)
 205 {
 206         gfs2_unfreeze_fs(sb->s_fs_info);
 207 }
 208
 209 /**
 210  * gfs2_statfs - Gather and return stats about the filesystem
 211  * @sb: The superblock
 212  * @statfsbuf: The buffer
 213  *
 214  * Returns: 0 on success or error code
 215  */
 216
 217 static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 218 {
 219         struct super_block *sb = dentry->d_inode->i_sb;
 220         struct gfs2_sbd *sdp = sb->s_fs_info;
 221         struct gfs2_statfs_change_host sc;
 222         int error;
 223
 224         if (gfs2_tune_get(sdp, gt_statfs_slow))
 225                 error = gfs2_statfs_slow(sdp, &sc);
 226         else
 227                 error = gfs2_statfs_i(sdp, &sc);
 228
 229         if (error)
 230                 return error;
 231
 232         buf->f_type = GFS2_MAGIC;
 233         buf->f_bsize = sdp->sd_sb.sb_bsize;
 234         buf->f_blocks = sc.sc_total;
 235         buf->f_bfree = sc.sc_free;
 236         buf->f_bavail = sc.sc_free;
 237         buf->f_files = sc.sc_dinodes + sc.sc_free;
 238         buf->f_ffree = sc.sc_free;
 239         buf->f_namelen = GFS2_FNAMESIZE;
 240
 241         return 0;
 242 }
 243
 244 /**
 245  * gfs2_remount_fs - called when the FS is remounted
 246  * @sb:  the filesystem
 247  * @flags:  the remount flags
 248  * @data:  extra data passed in (not used right now)
 249  *
 250  * Returns: errno
 251  */
 252
 253 static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
 254 {
 255         struct gfs2_sbd *sdp = sb->s_fs_info;
 256         int error;
 257
 258         error = gfs2_mount_args(sdp, data, 1);
 259         if (error)
 260                 return error;
 261
 262         if (sdp->sd_args.ar_spectator)
 263                 *flags |= MS_RDONLY;
 264         else {
 265                 if (*flags & MS_RDONLY) {
 266                         if (!(sb->s_flags & MS_RDONLY))
 267                                 error = gfs2_make_fs_ro(sdp);
 268                 } else if (!(*flags & MS_RDONLY) &&
 269                            (sb->s_flags & MS_RDONLY)) {
 270                         error = gfs2_make_fs_rw(sdp);
 271                 }
 272         }
 273
 274         if (*flags & (MS_NOATIME | MS_NODIRATIME))
 275                 set_bit(SDF_NOATIME, &sdp->sd_flags);
 276         else
 277                 clear_bit(SDF_NOATIME, &sdp->sd_flags);
 278
 279         /* Don't let the VFS update atimes.  GFS2 handles this itself. */
 280         *flags |= MS_NOATIME | MS_NODIRATIME;
 281
 282         return error;
 283 }
 284
 285 /**
 286  * gfs2_drop_inode - Drop an inode (test for remote unlink)
 287  * @inode: The inode to drop
 288  *
 289  * If we've received a callback on an iopen lock then its because a
 290  * remote node tried to deallocate the inode but failed due to this node
 291  * still having the inode open. Here we mark the link count zero
 292  * since we know that it must have reached zero if the GLF_DEMOTE flag
 293  * is set on the iopen glock. If we didn't do a disk read since the
 294  * remote node removed the final link then we might otherwise miss
 295  * this event. This check ensures that this node will deallocate the
 296  * inode's blocks, or alternatively pass the baton on to another
 297  * node for later deallocation.
 298  */
 299 static void gfs2_drop_inode(struct inode *inode)
 300 {
 301         if (inode->i_private && inode->i_nlink) {
 302                 struct gfs2_inode *ip = GFS2_I(inode);
 303                 struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
 304                 if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
 305                         clear_nlink(inode);
 306         }
 307         generic_drop_inode(inode);
 308 }
 309
 310 /**
 311  * gfs2_clear_inode - Deallocate an inode when VFS is done with it
 312  * @inode: The VFS inode
 313  *
 314  */
 315
 316 static void gfs2_clear_inode(struct inode *inode)
 317 {
 318         /* This tells us its a "real" inode and not one which only
 319          * serves to contain an address space (see rgrp.c, meta_io.c)
 320          * which therefore doesn't have its own glocks.
 321          */
 322         if (inode->i_private) {
 323                 struct gfs2_inode *ip = GFS2_I(inode);
 324                 ip->i_gl->gl_object = NULL;
 325                 gfs2_glock_schedule_for_reclaim(ip->i_gl);
 326                 gfs2_glock_put(ip->i_gl);
 327                 ip->i_gl = NULL;
 328                 if (ip->i_iopen_gh.gh_gl) {
 329                         ip->i_iopen_gh.gh_gl->gl_object = NULL;
 330                         gfs2_glock_dq_uninit(&ip->i_iopen_gh);
 331                 }
 332         }
 333 }
 334
 335 /**
 336  * gfs2_show_options - Show mount options for /proc/mounts
 337  * @s: seq_file structure
 338  * @mnt: vfsmount
 339  *
 340  * Returns: 0 on success or error code
 341  */
 342
 343 static int gfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
 344 {
 345         struct gfs2_sbd *sdp = mnt->mnt_sb->s_fs_info;
 346         struct gfs2_args *args = &sdp->sd_args;
 347
 348         if (args->ar_lockproto[0])
 349                 seq_printf(s, ",lockproto=%s", args->ar_lockproto);
 350         if (args->ar_locktable[0])
 351                 seq_printf(s, ",locktable=%s", args->ar_locktable);
 352         if (args->ar_hostdata[0])
 353                 seq_printf(s, ",hostdata=%s", args->ar_hostdata);
 354         if (args->ar_spectator)
 355                 seq_printf(s, ",spectator");
 356         if (args->ar_ignore_local_fs)
 357                 seq_printf(s, ",ignore_local_fs");
 358         if (args->ar_localflocks)
 359                 seq_printf(s, ",localflocks");
 360         if (args->ar_localcaching)
 361                 seq_printf(s, ",localcaching");
 362         if (args->ar_debug)
 363                 seq_printf(s, ",debug");
 364         if (args->ar_upgrade)
 365                 seq_printf(s, ",upgrade");
 366         if (args->ar_num_glockd != GFS2_GLOCKD_DEFAULT)
 367                 seq_printf(s, ",num_glockd=%u", args->ar_num_glockd);
 368         if (args->ar_posix_acl)
 369                 seq_printf(s, ",acl");
 370         if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
 371                 char *state;
 372                 switch (args->ar_quota) {
 373                 case GFS2_QUOTA_OFF:
 374                         state = "off";
 375                         break;
 376                 case GFS2_QUOTA_ACCOUNT:
 377                         state = "account";
 378                         break;
 379                 case GFS2_QUOTA_ON:
 380                         state = "on";
 381                         break;
 382                 default:
 383                         state = "unknown";
 384                         break;
 385                 }
 386                 seq_printf(s, ",quota=%s", state);
 387         }
 388         if (args->ar_suiddir)
 389                 seq_printf(s, ",suiddir");
 390         if (args->ar_data != GFS2_DATA_DEFAULT) {
 391                 char *state;
 392                 switch (args->ar_data) {
 393                 case GFS2_DATA_WRITEBACK:
 394                         state = "writeback";
 395                         break;
 396                 case GFS2_DATA_ORDERED:
 397                         state = "ordered";
 398                         break;
 399                 default:
 400                         state = "unknown";
 401                         break;
 402                 }
 403                 seq_printf(s, ",data=%s", state);
 404         }
 405
 406         return 0;
 407 }
 408
 409 /*
 410  * We have to (at the moment) hold the inodes main lock to cover
 411  * the gap between unlocking the shared lock on the iopen lock and
 412  * taking the exclusive lock. I'd rather do a shared -> exclusive
 413  * conversion on the iopen lock, but we can change that later. This
 414  * is safe, just less efficient.
 415  */
 416 static void gfs2_delete_inode(struct inode *inode)
 417 {
 418         struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
 419         struct gfs2_inode *ip = GFS2_I(inode);
 420         struct gfs2_holder gh;
 421         int error;
 422
 423         if (!inode->i_private)
 424                 goto out;
 425
 426         error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
 427         if (unlikely(error)) {
 428                 gfs2_glock_dq_uninit(&ip->i_iopen_gh);
 429                 goto out;
 430         }
 431
 432         gfs2_glock_dq_wait(&ip->i_iopen_gh);
 433         gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
 434         error = gfs2_glock_nq(&ip->i_iopen_gh);
 435         if (error)
 436                 goto out_uninit;
 437
 438         if (S_ISDIR(inode->i_mode) &&
 439             (ip->i_di.di_flags & GFS2_DIF_EXHASH)) {
 440                 error = gfs2_dir_exhash_dealloc(ip);
 441                 if (error)
 442                         goto out_unlock;
 443         }
 444
 445         if (ip->i_di.di_eattr) {
 446                 error = gfs2_ea_dealloc(ip);
 447                 if (error)
 448                         goto out_unlock;
 449         }
 450
 451         if (!gfs2_is_stuffed(ip)) {
 452                 error = gfs2_file_dealloc(ip);
 453                 if (error)
 454                         goto out_unlock;
 455         }
 456
 457         error = gfs2_dinode_dealloc(ip);
 458         if (error)
 459                 goto out_unlock;
 460
 461         error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
 462         if (error)
 463                 goto out_unlock;
 464         /* Needs to be done before glock release & also in a transaction */
 465         truncate_inode_pages(&inode->i_data, 0);
 466         gfs2_trans_end(sdp);
 467
 468 out_unlock:
 469         gfs2_glock_dq(&ip->i_iopen_gh);
 470 out_uninit:
 471         gfs2_holder_uninit(&ip->i_iopen_gh);
 472         gfs2_glock_dq_uninit(&gh);
 473         if (error && error != GLR_TRYFAILED)
 474                 fs_warn(sdp, "gfs2_delete_inode: %d\n", error);
 475 out:
 476         truncate_inode_pages(&inode->i_data, 0);
 477         clear_inode(inode);
 478 }
 479
 480
 481
 482 static struct inode *gfs2_alloc_inode(struct super_block *sb)
 483 {
 484         struct gfs2_inode *ip;
 485
 486         ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
 487         if (ip) {
 488                 ip->i_flags = 0;
 489                 ip->i_gl = NULL;
 490         }
 491         return &ip->i_inode;
 492 }
 493
 494 static void gfs2_destroy_inode(struct inode *inode)
 495 {
 496         kmem_cache_free(gfs2_inode_cachep, inode);
 497 }
 498
 499 const struct super_operations gfs2_super_ops = {
 500         .alloc_inode            = gfs2_alloc_inode,
 501         .destroy_inode          = gfs2_destroy_inode,
 502         .write_inode            = gfs2_write_inode,
 503         .delete_inode           = gfs2_delete_inode,
 504         .put_super              = gfs2_put_super,
 505         .write_super            = gfs2_write_super,
 506         .sync_fs                = gfs2_sync_fs,
 507         .write_super_lockfs     = gfs2_write_super_lockfs,
 508         .unlockfs               = gfs2_unlockfs,
 509         .statfs                 = gfs2_statfs,
 510         .remount_fs             = gfs2_remount_fs,
 511         .clear_inode            = gfs2_clear_inode,
 512         .drop_inode             = gfs2_drop_inode,
 513         .show_options           = gfs2_show_options,
 514 };
 515