fs/jfs/super.c

   1 /*
   2  *   Copyright (C) International Business Machines Corp., 2000-2004
   3  *   Portions Copyright (C) Christoph Hellwig, 2001-2002
   4  *
   5  *   This program is free software;  you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation; either version 2 of the License, or
   8  *   (at your option) any later version.
   9  *
  10  *   This program is distributed in the hope that it will be useful,
  11  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  13  *   the GNU General Public License for more details.
  14  *
  15  *   You should have received a copy of the GNU General Public License
  16  *   along with this program;  if not, write to the Free Software
  17  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  18  */
  19
  20 #include <linux/fs.h>
  21 #include <linux/module.h>
  22 #include <linux/parser.h>
  23 #include <linux/completion.h>
  24 #include <linux/vfs.h>
  25 #include <linux/quotaops.h>
  26 #include <linux/mount.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/kthread.h>
  29 #include <linux/posix_acl.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/crc32.h>
  33 #include <asm/uaccess.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/smp_lock.h>
  36
  37 #include "jfs_incore.h"
  38 #include "jfs_filsys.h"
  39 #include "jfs_inode.h"
  40 #include "jfs_metapage.h"
  41 #include "jfs_superblock.h"
  42 #include "jfs_dmap.h"
  43 #include "jfs_imap.h"
  44 #include "jfs_acl.h"
  45 #include "jfs_debug.h"
  46
  47 MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
  48 MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
  49 MODULE_LICENSE("GPL");
  50
  51 static struct kmem_cache * jfs_inode_cachep;
  52
  53 static const struct super_operations jfs_super_operations;
  54 static const struct export_operations jfs_export_operations;
  55 static struct file_system_type jfs_fs_type;
  56
  57 #define MAX_COMMIT_THREADS 64
  58 static int commit_threads = 0;
  59 module_param(commit_threads, int, 0);
  60 MODULE_PARM_DESC(commit_threads, "Number of commit threads");
  61
  62 static struct task_struct *jfsCommitThread[MAX_COMMIT_THREADS];
  63 struct task_struct *jfsIOthread;
  64 struct task_struct *jfsSyncThread;
  65
  66 #ifdef CONFIG_JFS_DEBUG
  67 int jfsloglevel = JFS_LOGLEVEL_WARN;
  68 module_param(jfsloglevel, int, 0644);
  69 MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
  70 #endif
  71
  72 static void jfs_handle_error(struct super_block *sb)
  73 {
  74         struct jfs_sb_info *sbi = JFS_SBI(sb);
  75
  76         if (sb->s_flags & MS_RDONLY)
  77                 return;
  78
  79         updateSuper(sb, FM_DIRTY);
  80
  81         if (sbi->flag & JFS_ERR_PANIC)
  82                 panic("JFS (device %s): panic forced after error\n",
  83                         sb->s_id);
  84         else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
  85                 jfs_err("ERROR: (device %s): remounting filesystem "
  86                         "as read-only\n",
  87                         sb->s_id);
  88                 sb->s_flags |= MS_RDONLY;
  89         }
  90
  91         /* nothing is done for continue beyond marking the superblock dirty */
  92 }
  93
  94 void jfs_error(struct super_block *sb, const char * function, ...)
  95 {
  96         static char error_buf[256];
  97         va_list args;
  98
  99         va_start(args, function);
 100         vsnprintf(error_buf, sizeof(error_buf), function, args);
 101         va_end(args);
 102
 103         printk(KERN_ERR "ERROR: (device %s): %s\n", sb->s_id, error_buf);
 104
 105         jfs_handle_error(sb);
 106 }
 107
 108 static struct inode *jfs_alloc_inode(struct super_block *sb)
 109 {
 110         struct jfs_inode_info *jfs_inode;
 111
 112         jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
 113         if (!jfs_inode)
 114                 return NULL;
 115         return &jfs_inode->vfs_inode;
 116 }
 117
 118 static void jfs_destroy_inode(struct inode *inode)
 119 {
 120         struct jfs_inode_info *ji = JFS_IP(inode);
 121
 122         BUG_ON(!list_empty(&ji->anon_inode_list));
 123
 124         spin_lock_irq(&ji->ag_lock);
 125         if (ji->active_ag != -1) {
 126                 struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
 127                 atomic_dec(&bmap->db_active[ji->active_ag]);
 128                 ji->active_ag = -1;
 129         }
 130         spin_unlock_irq(&ji->ag_lock);
 131         kmem_cache_free(jfs_inode_cachep, ji);
 132 }
 133
 134 static void jfs_clear_inode(struct inode *inode)
 135 {
 136         dquot_drop(inode);
 137 }
 138
 139 static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 140 {
 141         struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
 142         s64 maxinodes;
 143         struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
 144
 145         jfs_info("In jfs_statfs");
 146         buf->f_type = JFS_SUPER_MAGIC;
 147         buf->f_bsize = sbi->bsize;
 148         buf->f_blocks = sbi->bmap->db_mapsize;
 149         buf->f_bfree = sbi->bmap->db_nfree;
 150         buf->f_bavail = sbi->bmap->db_nfree;
 151         /*
 152          * If we really return the number of allocated & free inodes, some
 153          * applications will fail because they won't see enough free inodes.
 154          * We'll try to calculate some guess as to how may inodes we can
 155          * really allocate
 156          *
 157          * buf->f_files = atomic_read(&imap->im_numinos);
 158          * buf->f_ffree = atomic_read(&imap->im_numfree);
 159          */
 160         maxinodes = min((s64) atomic_read(&imap->im_numinos) +
 161                         ((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
 162                          << L2INOSPEREXT), (s64) 0xffffffffLL);
 163         buf->f_files = maxinodes;
 164         buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
 165                                     atomic_read(&imap->im_numfree));
 166         buf->f_fsid.val[0] = (u32)crc32_le(0, sbi->uuid, sizeof(sbi->uuid)/2);
 167         buf->f_fsid.val[1] = (u32)crc32_le(0, sbi->uuid + sizeof(sbi->uuid)/2,
 168                                         sizeof(sbi->uuid)/2);
 169
 170         buf->f_namelen = JFS_NAME_MAX;
 171         return 0;
 172 }
 173
 174 static void jfs_put_super(struct super_block *sb)
 175 {
 176         struct jfs_sb_info *sbi = JFS_SBI(sb);
 177         int rc;
 178
 179         jfs_info("In jfs_put_super");
 180
 181         lock_kernel();
 182
 183         rc = jfs_umount(sb);
 184         if (rc)
 185                 jfs_err("jfs_umount failed with return code %d", rc);
 186
 187         unload_nls(sbi->nls_tab);
 188
 189         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 190         iput(sbi->direct_inode);
 191
 192         kfree(sbi);
 193
 194         unlock_kernel();
 195 }
 196
 197 enum {
 198         Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
 199         Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
 200         Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask
 201 };
 202
 203 static const match_table_t tokens = {
 204         {Opt_integrity, "integrity"},
 205         {Opt_nointegrity, "nointegrity"},
 206         {Opt_iocharset, "iocharset=%s"},
 207         {Opt_resize, "resize=%u"},
 208         {Opt_resize_nosize, "resize"},
 209         {Opt_errors, "errors=%s"},
 210         {Opt_ignore, "noquota"},
 211         {Opt_ignore, "quota"},
 212         {Opt_usrquota, "usrquota"},
 213         {Opt_grpquota, "grpquota"},
 214         {Opt_uid, "uid=%u"},
 215         {Opt_gid, "gid=%u"},
 216         {Opt_umask, "umask=%u"},
 217         {Opt_err, NULL}
 218 };
 219
 220 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 221                          int *flag)
 222 {
 223         void *nls_map = (void *)-1;     /* -1: no change;  NULL: none */
 224         char *p;
 225         struct jfs_sb_info *sbi = JFS_SBI(sb);
 226
 227         *newLVSize = 0;
 228
 229         if (!options)
 230                 return 1;
 231
 232         while ((p = strsep(&options, ",")) != NULL) {
 233                 substring_t args[MAX_OPT_ARGS];
 234                 int token;
 235                 if (!*p)
 236                         continue;
 237
 238                 token = match_token(p, tokens, args);
 239                 switch (token) {
 240                 case Opt_integrity:
 241                         *flag &= ~JFS_NOINTEGRITY;
 242                         break;
 243                 case Opt_nointegrity:
 244                         *flag |= JFS_NOINTEGRITY;
 245                         break;
 246                 case Opt_ignore:
 247                         /* Silently ignore the quota options */
 248                         /* Don't do anything ;-) */
 249                         break;
 250                 case Opt_iocharset:
 251                         if (nls_map && nls_map != (void *) -1)
 252                                 unload_nls(nls_map);
 253                         if (!strcmp(args[0].from, "none"))
 254                                 nls_map = NULL;
 255                         else {
 256                                 nls_map = load_nls(args[0].from);
 257                                 if (!nls_map) {
 258                                         printk(KERN_ERR
 259                                                "JFS: charset not found\n");
 260                                         goto cleanup;
 261                                 }
 262                         }
 263                         break;
 264                 case Opt_resize:
 265                 {
 266                         char *resize = args[0].from;
 267                         *newLVSize = simple_strtoull(resize, &resize, 0);
 268                         break;
 269                 }
 270                 case Opt_resize_nosize:
 271                 {
 272                         *newLVSize = sb->s_bdev->bd_inode->i_size >>
 273                                 sb->s_blocksize_bits;
 274                         if (*newLVSize == 0)
 275                                 printk(KERN_ERR
 276                                        "JFS: Cannot determine volume size\n");
 277                         break;
 278                 }
 279                 case Opt_errors:
 280                 {
 281                         char *errors = args[0].from;
 282                         if (!errors || !*errors)
 283                                 goto cleanup;
 284                         if (!strcmp(errors, "continue")) {
 285                                 *flag &= ~JFS_ERR_REMOUNT_RO;
 286                                 *flag &= ~JFS_ERR_PANIC;
 287                                 *flag |= JFS_ERR_CONTINUE;
 288                         } else if (!strcmp(errors, "remount-ro")) {
 289                                 *flag &= ~JFS_ERR_CONTINUE;
 290                                 *flag &= ~JFS_ERR_PANIC;
 291                                 *flag |= JFS_ERR_REMOUNT_RO;
 292                         } else if (!strcmp(errors, "panic")) {
 293                                 *flag &= ~JFS_ERR_CONTINUE;
 294                                 *flag &= ~JFS_ERR_REMOUNT_RO;
 295                                 *flag |= JFS_ERR_PANIC;
 296                         } else {
 297                                 printk(KERN_ERR
 298                                        "JFS: %s is an invalid error handler\n",
 299                                        errors);
 300                                 goto cleanup;
 301                         }
 302                         break;
 303                 }
 304
 305 #ifdef CONFIG_QUOTA
 306                 case Opt_quota:
 307                 case Opt_usrquota:
 308                         *flag |= JFS_USRQUOTA;
 309                         break;
 310                 case Opt_grpquota:
 311                         *flag |= JFS_GRPQUOTA;
 312                         break;
 313 #else
 314                 case Opt_usrquota:
 315                 case Opt_grpquota:
 316                 case Opt_quota:
 317                         printk(KERN_ERR
 318                                "JFS: quota operations not supported\n");
 319                         break;
 320 #endif
 321                 case Opt_uid:
 322                 {
 323                         char *uid = args[0].from;
 324                         sbi->uid = simple_strtoul(uid, &uid, 0);
 325                         break;
 326                 }
 327                 case Opt_gid:
 328                 {
 329                         char *gid = args[0].from;
 330                         sbi->gid = simple_strtoul(gid, &gid, 0);
 331                         break;
 332                 }
 333                 case Opt_umask:
 334                 {
 335                         char *umask = args[0].from;
 336                         sbi->umask = simple_strtoul(umask, &umask, 8);
 337                         if (sbi->umask & ~0777) {
 338                                 printk(KERN_ERR
 339                                        "JFS: Invalid value of umask\n");
 340                                 goto cleanup;
 341                         }
 342                         break;
 343                 }
 344                 default:
 345                         printk("jfs: Unrecognized mount option \"%s\" "
 346                                         " or missing value\n", p);
 347                         goto cleanup;
 348                 }
 349         }
 350
 351         if (nls_map != (void *) -1) {
 352                 /* Discard old (if remount) */
 353                 unload_nls(sbi->nls_tab);
 354                 sbi->nls_tab = nls_map;
 355         }
 356         return 1;
 357
 358 cleanup:
 359         if (nls_map && nls_map != (void *) -1)
 360                 unload_nls(nls_map);
 361         return 0;
 362 }
 363
 364 static int jfs_remount(struct super_block *sb, int *flags, char *data)
 365 {
 366         s64 newLVSize = 0;
 367         int rc = 0;
 368         int flag = JFS_SBI(sb)->flag;
 369         int ret;
 370
 371         if (!parse_options(data, sb, &newLVSize, &flag)) {
 372                 return -EINVAL;
 373         }
 374         lock_kernel();
 375         if (newLVSize) {
 376                 if (sb->s_flags & MS_RDONLY) {
 377                         printk(KERN_ERR
 378                   "JFS: resize requires volume to be mounted read-write\n");
 379                         unlock_kernel();
 380                         return -EROFS;
 381                 }
 382                 rc = jfs_extendfs(sb, newLVSize, 0);
 383                 if (rc) {
 384                         unlock_kernel();
 385                         return rc;
 386                 }
 387         }
 388
 389         if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
 390                 /*
 391                  * Invalidate any previously read metadata.  fsck may have
 392                  * changed the on-disk data since we mounted r/o
 393                  */
 394                 truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
 395
 396                 JFS_SBI(sb)->flag = flag;
 397                 ret = jfs_mount_rw(sb, 1);
 398                 unlock_kernel();
 399                 return ret;
 400         }
 401         if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
 402                 rc = jfs_umount_rw(sb);
 403                 JFS_SBI(sb)->flag = flag;
 404                 unlock_kernel();
 405                 return rc;
 406         }
 407         if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
 408                 if (!(sb->s_flags & MS_RDONLY)) {
 409                         rc = jfs_umount_rw(sb);
 410                         if (rc) {
 411                                 unlock_kernel();
 412                                 return rc;
 413                         }
 414                         JFS_SBI(sb)->flag = flag;
 415                         ret = jfs_mount_rw(sb, 1);
 416                         unlock_kernel();
 417                         return ret;
 418                 }
 419         JFS_SBI(sb)->flag = flag;
 420
 421         unlock_kernel();
 422         return 0;
 423 }
 424
 425 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 426 {
 427         struct jfs_sb_info *sbi;
 428         struct inode *inode;
 429         int rc;
 430         s64 newLVSize = 0;
 431         int flag, ret = -EINVAL;
 432
 433         jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
 434
 435         if (!new_valid_dev(sb->s_bdev->bd_dev))
 436                 return -EOVERFLOW;
 437
 438         sbi = kzalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
 439         if (!sbi)
 440                 return -ENOMEM;
 441         sb->s_fs_info = sbi;
 442         sbi->sb = sb;
 443         sbi->uid = sbi->gid = sbi->umask = -1;
 444
 445         /* initialize the mount flag and determine the default error handler */
 446         flag = JFS_ERR_REMOUNT_RO;
 447
 448         if (!parse_options((char *) data, sb, &newLVSize, &flag)) {
 449                 kfree(sbi);
 450                 return -EINVAL;
 451         }
 452         sbi->flag = flag;
 453
 454 #ifdef CONFIG_JFS_POSIX_ACL
 455         sb->s_flags |= MS_POSIXACL;
 456 #endif
 457
 458         if (newLVSize) {
 459                 printk(KERN_ERR "resize option for remount only\n");
 460                 return -EINVAL;
 461         }
 462
 463         /*
 464          * Initialize blocksize to 4K.
 465          */
 466         sb_set_blocksize(sb, PSIZE);
 467
 468         /*
 469          * Set method vectors.
 470          */
 471         sb->s_op = &jfs_super_operations;
 472         sb->s_export_op = &jfs_export_operations;
 473
 474         /*
 475          * Initialize direct-mapping inode/address-space
 476          */
 477         inode = new_inode(sb);
 478         if (inode == NULL) {
 479                 ret = -ENOMEM;
 480                 goto out_kfree;
 481         }
 482         inode->i_ino = 0;
 483         inode->i_nlink = 1;
 484         inode->i_size = sb->s_bdev->bd_inode->i_size;
 485         inode->i_mapping->a_ops = &jfs_metapage_aops;
 486         insert_inode_hash(inode);
 487         mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
 488
 489         sbi->direct_inode = inode;
 490
 491         rc = jfs_mount(sb);
 492         if (rc) {
 493                 if (!silent) {
 494                         jfs_err("jfs_mount failed w/return code = %d", rc);
 495                 }
 496                 goto out_mount_failed;
 497         }
 498         if (sb->s_flags & MS_RDONLY)
 499                 sbi->log = NULL;
 500         else {
 501                 rc = jfs_mount_rw(sb, 0);
 502                 if (rc) {
 503                         if (!silent) {
 504                                 jfs_err("jfs_mount_rw failed, return code = %d",
 505                                         rc);
 506                         }
 507                         goto out_no_rw;
 508                 }
 509         }
 510
 511         sb->s_magic = JFS_SUPER_MAGIC;
 512
 513         inode = jfs_iget(sb, ROOT_I);
 514         if (IS_ERR(inode)) {
 515                 ret = PTR_ERR(inode);
 516                 goto out_no_rw;
 517         }
 518         sb->s_root = d_alloc_root(inode);
 519         if (!sb->s_root)
 520                 goto out_no_root;
 521
 522         if (sbi->mntflag & JFS_OS2)
 523                 sb->s_root->d_op = &jfs_ci_dentry_operations;
 524
 525         /* logical blocks are represented by 40 bits in pxd_t, etc. */
 526         sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
 527 #if BITS_PER_LONG == 32
 528         /*
 529          * Page cache is indexed by long.
 530          * I would use MAX_LFS_FILESIZE, but it's only half as big
 531          */
 532         sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, (u64)sb->s_maxbytes);
 533 #endif
 534         sb->s_time_gran = 1;
 535         return 0;
 536
 537 out_no_root:
 538         jfs_err("jfs_read_super: get root dentry failed");
 539         iput(inode);
 540
 541 out_no_rw:
 542         rc = jfs_umount(sb);
 543         if (rc) {
 544                 jfs_err("jfs_umount failed with return code %d", rc);
 545         }
 546 out_mount_failed:
 547         filemap_write_and_wait(sbi->direct_inode->i_mapping);
 548         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 549         make_bad_inode(sbi->direct_inode);
 550         iput(sbi->direct_inode);
 551         sbi->direct_inode = NULL;
 552 out_kfree:
 553         if (sbi->nls_tab)
 554                 unload_nls(sbi->nls_tab);
 555         kfree(sbi);
 556         return ret;
 557 }
 558
 559 static int jfs_freeze(struct super_block *sb)
 560 {
 561         struct jfs_sb_info *sbi = JFS_SBI(sb);
 562         struct jfs_log *log = sbi->log;
 563
 564         if (!(sb->s_flags & MS_RDONLY)) {
 565                 txQuiesce(sb);
 566                 lmLogShutdown(log);
 567                 updateSuper(sb, FM_CLEAN);
 568         }
 569         return 0;
 570 }
 571
 572 static int jfs_unfreeze(struct super_block *sb)
 573 {
 574         struct jfs_sb_info *sbi = JFS_SBI(sb);
 575         struct jfs_log *log = sbi->log;
 576         int rc = 0;
 577
 578         if (!(sb->s_flags & MS_RDONLY)) {
 579                 updateSuper(sb, FM_MOUNT);
 580                 if ((rc = lmLogInit(log)))
 581                         jfs_err("jfs_unlock failed with return code %d", rc);
 582                 else
 583                         txResume(sb);
 584         }
 585         return 0;
 586 }
 587
 588 static int jfs_get_sb(struct file_system_type *fs_type,
 589         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 590 {
 591         return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super,
 592                            mnt);
 593 }
 594
 595 static int jfs_sync_fs(struct super_block *sb, int wait)
 596 {
 597         struct jfs_log *log = JFS_SBI(sb)->log;
 598
 599         /* log == NULL indicates read-only mount */
 600         if (log) {
 601                 jfs_flush_journal(log, wait);
 602                 jfs_syncpt(log, 0);
 603         }
 604
 605         return 0;
 606 }
 607
 608 static int jfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
 609 {
 610         struct jfs_sb_info *sbi = JFS_SBI(vfs->mnt_sb);
 611
 612         if (sbi->uid != -1)
 613                 seq_printf(seq, ",uid=%d", sbi->uid);
 614         if (sbi->gid != -1)
 615                 seq_printf(seq, ",gid=%d", sbi->gid);
 616         if (sbi->umask != -1)
 617                 seq_printf(seq, ",umask=%03o", sbi->umask);
 618         if (sbi->flag & JFS_NOINTEGRITY)
 619                 seq_puts(seq, ",nointegrity");
 620         if (sbi->nls_tab)
 621                 seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
 622         if (sbi->flag & JFS_ERR_CONTINUE)
 623                 seq_printf(seq, ",errors=continue");
 624         if (sbi->flag & JFS_ERR_PANIC)
 625                 seq_printf(seq, ",errors=panic");
 626
 627 #ifdef CONFIG_QUOTA
 628         if (sbi->flag & JFS_USRQUOTA)
 629                 seq_puts(seq, ",usrquota");
 630
 631         if (sbi->flag & JFS_GRPQUOTA)
 632                 seq_puts(seq, ",grpquota");
 633 #endif
 634
 635         return 0;
 636 }
 637
 638 #ifdef CONFIG_QUOTA
 639
 640 /* Read data from quotafile - avoid pagecache and such because we cannot afford
 641  * acquiring the locks... As quota files are never truncated and quota code
 642  * itself serializes the operations (and noone else should touch the files)
 643  * we don't have to be afraid of races */
 644 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
 645                               size_t len, loff_t off)
 646 {
 647         struct inode *inode = sb_dqopt(sb)->files[type];
 648         sector_t blk = off >> sb->s_blocksize_bits;
 649         int err = 0;
 650         int offset = off & (sb->s_blocksize - 1);
 651         int tocopy;
 652         size_t toread;
 653         struct buffer_head tmp_bh;
 654         struct buffer_head *bh;
 655         loff_t i_size = i_size_read(inode);
 656
 657         if (off > i_size)
 658                 return 0;
 659         if (off+len > i_size)
 660                 len = i_size-off;
 661         toread = len;
 662         while (toread > 0) {
 663                 tocopy = sb->s_blocksize - offset < toread ?
 664                                 sb->s_blocksize - offset : toread;
 665
 666                 tmp_bh.b_state = 0;
 667                 tmp_bh.b_size = 1 << inode->i_blkbits;
 668                 err = jfs_get_block(inode, blk, &tmp_bh, 0);
 669                 if (err)
 670                         return err;
 671                 if (!buffer_mapped(&tmp_bh))    /* A hole? */
 672                         memset(data, 0, tocopy);
 673                 else {
 674                         bh = sb_bread(sb, tmp_bh.b_blocknr);
 675                         if (!bh)
 676                                 return -EIO;
 677                         memcpy(data, bh->b_data+offset, tocopy);
 678                         brelse(bh);
 679                 }
 680                 offset = 0;
 681                 toread -= tocopy;
 682                 data += tocopy;
 683                 blk++;
 684         }
 685         return len;
 686 }
 687
 688 /* Write to quotafile */
 689 static ssize_t jfs_quota_write(struct super_block *sb, int type,
 690                                const char *data, size_t len, loff_t off)
 691 {
 692         struct inode *inode = sb_dqopt(sb)->files[type];
 693         sector_t blk = off >> sb->s_blocksize_bits;
 694         int err = 0;
 695         int offset = off & (sb->s_blocksize - 1);
 696         int tocopy;
 697         size_t towrite = len;
 698         struct buffer_head tmp_bh;
 699         struct buffer_head *bh;
 700
 701         mutex_lock(&inode->i_mutex);
 702         while (towrite > 0) {
 703                 tocopy = sb->s_blocksize - offset < towrite ?
 704                                 sb->s_blocksize - offset : towrite;
 705
 706                 tmp_bh.b_state = 0;
 707                 tmp_bh.b_size = 1 << inode->i_blkbits;
 708                 err = jfs_get_block(inode, blk, &tmp_bh, 1);
 709                 if (err)
 710                         goto out;
 711                 if (offset || tocopy != sb->s_blocksize)
 712                         bh = sb_bread(sb, tmp_bh.b_blocknr);
 713                 else
 714                         bh = sb_getblk(sb, tmp_bh.b_blocknr);
 715                 if (!bh) {
 716                         err = -EIO;
 717                         goto out;
 718                 }
 719                 lock_buffer(bh);
 720                 memcpy(bh->b_data+offset, data, tocopy);
 721                 flush_dcache_page(bh->b_page);
 722                 set_buffer_uptodate(bh);
 723                 mark_buffer_dirty(bh);
 724                 unlock_buffer(bh);
 725                 brelse(bh);
 726                 offset = 0;
 727                 towrite -= tocopy;
 728                 data += tocopy;
 729                 blk++;
 730         }
 731 out:
 732         if (len == towrite) {
 733                 mutex_unlock(&inode->i_mutex);
 734                 return err;
 735         }
 736         if (inode->i_size < off+len-towrite)
 737                 i_size_write(inode, off+len-towrite);
 738         inode->i_version++;
 739         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 740         mark_inode_dirty(inode);
 741         mutex_unlock(&inode->i_mutex);
 742         return len - towrite;
 743 }
 744
 745 #endif
 746
 747 static const struct super_operations jfs_super_operations = {
 748         .alloc_inode    = jfs_alloc_inode,
 749         .destroy_inode  = jfs_destroy_inode,
 750         .dirty_inode    = jfs_dirty_inode,
 751         .write_inode    = jfs_write_inode,
 752         .delete_inode   = jfs_delete_inode,
 753         .clear_inode    = jfs_clear_inode,
 754         .put_super      = jfs_put_super,
 755         .sync_fs        = jfs_sync_fs,
 756         .freeze_fs      = jfs_freeze,
 757         .unfreeze_fs    = jfs_unfreeze,
 758         .statfs         = jfs_statfs,
 759         .remount_fs     = jfs_remount,
 760         .show_options   = jfs_show_options,
 761 #ifdef CONFIG_QUOTA
 762         .quota_read     = jfs_quota_read,
 763         .quota_write    = jfs_quota_write,
 764 #endif
 765 };
 766
 767 static const struct export_operations jfs_export_operations = {
 768         .fh_to_dentry   = jfs_fh_to_dentry,
 769         .fh_to_parent   = jfs_fh_to_parent,
 770         .get_parent     = jfs_get_parent,
 771 };
 772
 773 static struct file_system_type jfs_fs_type = {
 774         .owner          = THIS_MODULE,
 775         .name           = "jfs",
 776         .get_sb         = jfs_get_sb,
 777         .kill_sb        = kill_block_super,
 778         .fs_flags       = FS_REQUIRES_DEV,
 779 };
 780
 781 static void init_once(void *foo)
 782 {
 783         struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
 784
 785         memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
 786         INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
 787         init_rwsem(&jfs_ip->rdwrlock);
 788         mutex_init(&jfs_ip->commit_mutex);
 789         init_rwsem(&jfs_ip->xattr_sem);
 790         spin_lock_init(&jfs_ip->ag_lock);
 791         jfs_ip->active_ag = -1;
 792         inode_init_once(&jfs_ip->vfs_inode);
 793 }
 794
 795 static int __init init_jfs_fs(void)
 796 {
 797         int i;
 798         int rc;
 799
 800         jfs_inode_cachep =
 801             kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
 802                             SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
 803                             init_once);
 804         if (jfs_inode_cachep == NULL)
 805                 return -ENOMEM;
 806
 807         /*
 808          * Metapage initialization
 809          */
 810         rc = metapage_init();
 811         if (rc) {
 812                 jfs_err("metapage_init failed w/rc = %d", rc);
 813                 goto free_slab;
 814         }
 815
 816         /*
 817          * Transaction Manager initialization
 818          */
 819         rc = txInit();
 820         if (rc) {
 821                 jfs_err("txInit failed w/rc = %d", rc);
 822                 goto free_metapage;
 823         }
 824
 825         /*
 826          * I/O completion thread (endio)
 827          */
 828         jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
 829         if (IS_ERR(jfsIOthread)) {
 830                 rc = PTR_ERR(jfsIOthread);
 831                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 832                 goto end_txmngr;
 833         }
 834
 835         if (commit_threads < 1)
 836                 commit_threads = num_online_cpus();
 837         if (commit_threads > MAX_COMMIT_THREADS)
 838                 commit_threads = MAX_COMMIT_THREADS;
 839
 840         for (i = 0; i < commit_threads; i++) {
 841                 jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL, "jfsCommit");
 842                 if (IS_ERR(jfsCommitThread[i])) {
 843                         rc = PTR_ERR(jfsCommitThread[i]);
 844                         jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 845                         commit_threads = i;
 846                         goto kill_committask;
 847                 }
 848         }
 849
 850         jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
 851         if (IS_ERR(jfsSyncThread)) {
 852                 rc = PTR_ERR(jfsSyncThread);
 853                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 854                 goto kill_committask;
 855         }
 856
 857 #ifdef PROC_FS_JFS
 858         jfs_proc_init();
 859 #endif
 860
 861         return register_filesystem(&jfs_fs_type);
 862
 863 kill_committask:
 864         for (i = 0; i < commit_threads; i++)
 865                 kthread_stop(jfsCommitThread[i]);
 866         kthread_stop(jfsIOthread);
 867 end_txmngr:
 868         txExit();
 869 free_metapage:
 870         metapage_exit();
 871 free_slab:
 872         kmem_cache_destroy(jfs_inode_cachep);
 873         return rc;
 874 }
 875
 876 static void __exit exit_jfs_fs(void)
 877 {
 878         int i;
 879
 880         jfs_info("exit_jfs_fs called");
 881
 882         txExit();
 883         metapage_exit();
 884
 885         kthread_stop(jfsIOthread);
 886         for (i = 0; i < commit_threads; i++)
 887                 kthread_stop(jfsCommitThread[i]);
 888         kthread_stop(jfsSyncThread);
 889 #ifdef PROC_FS_JFS
 890         jfs_proc_clean();
 891 #endif
 892         unregister_filesystem(&jfs_fs_type);
 893         kmem_cache_destroy(jfs_inode_cachep);
 894 }
 895
 896 module_init(init_jfs_fs)
 897 module_exit(exit_jfs_fs)