SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 135 {
 136         struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
 137         s64 maxinodes;
 138         struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
 139
 140         jfs_info("In jfs_statfs");
 141         buf->f_type = JFS_SUPER_MAGIC;
 142         buf->f_bsize = sbi->bsize;
 143         buf->f_blocks = sbi->bmap->db_mapsize;
 144         buf->f_bfree = sbi->bmap->db_nfree;
 145         buf->f_bavail = sbi->bmap->db_nfree;
 146         /*
 147          * If we really return the number of allocated & free inodes, some
 148          * applications will fail because they won't see enough free inodes.
 149          * We'll try to calculate some guess as to how may inodes we can
 150          * really allocate
 151          *
 152          * buf->f_files = atomic_read(&imap->im_numinos);
 153          * buf->f_ffree = atomic_read(&imap->im_numfree);
 154          */
 155         maxinodes = min((s64) atomic_read(&imap->im_numinos) +
 156                         ((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
 157                          << L2INOSPEREXT), (s64) 0xffffffffLL);
 158         buf->f_files = maxinodes;
 159         buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
 160                                     atomic_read(&imap->im_numfree));
 161         buf->f_fsid.val[0] = (u32)crc32_le(0, sbi->uuid, sizeof(sbi->uuid)/2);
 162         buf->f_fsid.val[1] = (u32)crc32_le(0, sbi->uuid + sizeof(sbi->uuid)/2,
 163                                         sizeof(sbi->uuid)/2);
 164
 165         buf->f_namelen = JFS_NAME_MAX;
 166         return 0;
 167 }
 168
 169 static void jfs_put_super(struct super_block *sb)
 170 {
 171         struct jfs_sb_info *sbi = JFS_SBI(sb);
 172         int rc;
 173
 174         jfs_info("In jfs_put_super");
 175
 176         lock_kernel();
 177
 178         rc = jfs_umount(sb);
 179         if (rc)
 180                 jfs_err("jfs_umount failed with return code %d", rc);
 181
 182         unload_nls(sbi->nls_tab);
 183
 184         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 185         iput(sbi->direct_inode);
 186
 187         kfree(sbi);
 188
 189         unlock_kernel();
 190 }
 191
 192 enum {
 193         Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
 194         Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
 195         Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask
 196 };
 197
 198 static const match_table_t tokens = {
 199         {Opt_integrity, "integrity"},
 200         {Opt_nointegrity, "nointegrity"},
 201         {Opt_iocharset, "iocharset=%s"},
 202         {Opt_resize, "resize=%u"},
 203         {Opt_resize_nosize, "resize"},
 204         {Opt_errors, "errors=%s"},
 205         {Opt_ignore, "noquota"},
 206         {Opt_ignore, "quota"},
 207         {Opt_usrquota, "usrquota"},
 208         {Opt_grpquota, "grpquota"},
 209         {Opt_uid, "uid=%u"},
 210         {Opt_gid, "gid=%u"},
 211         {Opt_umask, "umask=%u"},
 212         {Opt_err, NULL}
 213 };
 214
 215 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
 216                          int *flag)
 217 {
 218         void *nls_map = (void *)-1;     /* -1: no change;  NULL: none */
 219         char *p;
 220         struct jfs_sb_info *sbi = JFS_SBI(sb);
 221
 222         *newLVSize = 0;
 223
 224         if (!options)
 225                 return 1;
 226
 227         while ((p = strsep(&options, ",")) != NULL) {
 228                 substring_t args[MAX_OPT_ARGS];
 229                 int token;
 230                 if (!*p)
 231                         continue;
 232
 233                 token = match_token(p, tokens, args);
 234                 switch (token) {
 235                 case Opt_integrity:
 236                         *flag &= ~JFS_NOINTEGRITY;
 237                         break;
 238                 case Opt_nointegrity:
 239                         *flag |= JFS_NOINTEGRITY;
 240                         break;
 241                 case Opt_ignore:
 242                         /* Silently ignore the quota options */
 243                         /* Don't do anything ;-) */
 244                         break;
 245                 case Opt_iocharset:
 246                         if (nls_map && nls_map != (void *) -1)
 247                                 unload_nls(nls_map);
 248                         if (!strcmp(args[0].from, "none"))
 249                                 nls_map = NULL;
 250                         else {
 251                                 nls_map = load_nls(args[0].from);
 252                                 if (!nls_map) {
 253                                         printk(KERN_ERR
 254                                                "JFS: charset not found\n");
 255                                         goto cleanup;
 256                                 }
 257                         }
 258                         break;
 259                 case Opt_resize:
 260                 {
 261                         char *resize = args[0].from;
 262                         *newLVSize = simple_strtoull(resize, &resize, 0);
 263                         break;
 264                 }
 265                 case Opt_resize_nosize:
 266                 {
 267                         *newLVSize = sb->s_bdev->bd_inode->i_size >>
 268                                 sb->s_blocksize_bits;
 269                         if (*newLVSize == 0)
 270                                 printk(KERN_ERR
 271                                        "JFS: Cannot determine volume size\n");
 272                         break;
 273                 }
 274                 case Opt_errors:
 275                 {
 276                         char *errors = args[0].from;
 277                         if (!errors || !*errors)
 278                                 goto cleanup;
 279                         if (!strcmp(errors, "continue")) {
 280                                 *flag &= ~JFS_ERR_REMOUNT_RO;
 281                                 *flag &= ~JFS_ERR_PANIC;
 282                                 *flag |= JFS_ERR_CONTINUE;
 283                         } else if (!strcmp(errors, "remount-ro")) {
 284                                 *flag &= ~JFS_ERR_CONTINUE;
 285                                 *flag &= ~JFS_ERR_PANIC;
 286                                 *flag |= JFS_ERR_REMOUNT_RO;
 287                         } else if (!strcmp(errors, "panic")) {
 288                                 *flag &= ~JFS_ERR_CONTINUE;
 289                                 *flag &= ~JFS_ERR_REMOUNT_RO;
 290                                 *flag |= JFS_ERR_PANIC;
 291                         } else {
 292                                 printk(KERN_ERR
 293                                        "JFS: %s is an invalid error handler\n",
 294                                        errors);
 295                                 goto cleanup;
 296                         }
 297                         break;
 298                 }
 299
 300 #ifdef CONFIG_QUOTA
 301                 case Opt_quota:
 302                 case Opt_usrquota:
 303                         *flag |= JFS_USRQUOTA;
 304                         break;
 305                 case Opt_grpquota:
 306                         *flag |= JFS_GRPQUOTA;
 307                         break;
 308 #else
 309                 case Opt_usrquota:
 310                 case Opt_grpquota:
 311                 case Opt_quota:
 312                         printk(KERN_ERR
 313                                "JFS: quota operations not supported\n");
 314                         break;
 315 #endif
 316                 case Opt_uid:
 317                 {
 318                         char *uid = args[0].from;
 319                         sbi->uid = simple_strtoul(uid, &uid, 0);
 320                         break;
 321                 }
 322                 case Opt_gid:
 323                 {
 324                         char *gid = args[0].from;
 325                         sbi->gid = simple_strtoul(gid, &gid, 0);
 326                         break;
 327                 }
 328                 case Opt_umask:
 329                 {
 330                         char *umask = args[0].from;
 331                         sbi->umask = simple_strtoul(umask, &umask, 8);
 332                         if (sbi->umask & ~0777) {
 333                                 printk(KERN_ERR
 334                                        "JFS: Invalid value of umask\n");
 335                                 goto cleanup;
 336                         }
 337                         break;
 338                 }
 339                 default:
 340                         printk("jfs: Unrecognized mount option \"%s\" "
 341                                         " or missing value\n", p);
 342                         goto cleanup;
 343                 }
 344         }
 345
 346         if (nls_map != (void *) -1) {
 347                 /* Discard old (if remount) */
 348                 unload_nls(sbi->nls_tab);
 349                 sbi->nls_tab = nls_map;
 350         }
 351         return 1;
 352
 353 cleanup:
 354         if (nls_map && nls_map != (void *) -1)
 355                 unload_nls(nls_map);
 356         return 0;
 357 }
 358
 359 static int jfs_remount(struct super_block *sb, int *flags, char *data)
 360 {
 361         s64 newLVSize = 0;
 362         int rc = 0;
 363         int flag = JFS_SBI(sb)->flag;
 364         int ret;
 365
 366         if (!parse_options(data, sb, &newLVSize, &flag)) {
 367                 return -EINVAL;
 368         }
 369         lock_kernel();
 370         if (newLVSize) {
 371                 if (sb->s_flags & MS_RDONLY) {
 372                         printk(KERN_ERR
 373                   "JFS: resize requires volume to be mounted read-write\n");
 374                         unlock_kernel();
 375                         return -EROFS;
 376                 }
 377                 rc = jfs_extendfs(sb, newLVSize, 0);
 378                 if (rc) {
 379                         unlock_kernel();
 380                         return rc;
 381                 }
 382         }
 383
 384         if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
 385                 /*
 386                  * Invalidate any previously read metadata.  fsck may have
 387                  * changed the on-disk data since we mounted r/o
 388                  */
 389                 truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
 390
 391                 JFS_SBI(sb)->flag = flag;
 392                 ret = jfs_mount_rw(sb, 1);
 393                 unlock_kernel();
 394                 return ret;
 395         }
 396         if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
 397                 rc = jfs_umount_rw(sb);
 398                 JFS_SBI(sb)->flag = flag;
 399                 unlock_kernel();
 400                 return rc;
 401         }
 402         if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
 403                 if (!(sb->s_flags & MS_RDONLY)) {
 404                         rc = jfs_umount_rw(sb);
 405                         if (rc) {
 406                                 unlock_kernel();
 407                                 return rc;
 408                         }
 409                         JFS_SBI(sb)->flag = flag;
 410                         ret = jfs_mount_rw(sb, 1);
 411                         unlock_kernel();
 412                         return ret;
 413                 }
 414         JFS_SBI(sb)->flag = flag;
 415
 416         unlock_kernel();
 417         return 0;
 418 }
 419
 420 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
 421 {
 422         struct jfs_sb_info *sbi;
 423         struct inode *inode;
 424         int rc;
 425         s64 newLVSize = 0;
 426         int flag, ret = -EINVAL;
 427
 428         jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
 429
 430         if (!new_valid_dev(sb->s_bdev->bd_dev))
 431                 return -EOVERFLOW;
 432
 433         sbi = kzalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
 434         if (!sbi)
 435                 return -ENOMEM;
 436         sb->s_fs_info = sbi;
 437         sbi->sb = sb;
 438         sbi->uid = sbi->gid = sbi->umask = -1;
 439
 440         /* initialize the mount flag and determine the default error handler */
 441         flag = JFS_ERR_REMOUNT_RO;
 442
 443         if (!parse_options((char *) data, sb, &newLVSize, &flag)) {
 444                 kfree(sbi);
 445                 return -EINVAL;
 446         }
 447         sbi->flag = flag;
 448
 449 #ifdef CONFIG_JFS_POSIX_ACL
 450         sb->s_flags |= MS_POSIXACL;
 451 #endif
 452
 453         if (newLVSize) {
 454                 printk(KERN_ERR "resize option for remount only\n");
 455                 return -EINVAL;
 456         }
 457
 458         /*
 459          * Initialize blocksize to 4K.
 460          */
 461         sb_set_blocksize(sb, PSIZE);
 462
 463         /*
 464          * Set method vectors.
 465          */
 466         sb->s_op = &jfs_super_operations;
 467         sb->s_export_op = &jfs_export_operations;
 468
 469         /*
 470          * Initialize direct-mapping inode/address-space
 471          */
 472         inode = new_inode(sb);
 473         if (inode == NULL) {
 474                 ret = -ENOMEM;
 475                 goto out_kfree;
 476         }
 477         inode->i_ino = 0;
 478         inode->i_nlink = 1;
 479         inode->i_size = sb->s_bdev->bd_inode->i_size;
 480         inode->i_mapping->a_ops = &jfs_metapage_aops;
 481         insert_inode_hash(inode);
 482         mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
 483
 484         sbi->direct_inode = inode;
 485
 486         rc = jfs_mount(sb);
 487         if (rc) {
 488                 if (!silent) {
 489                         jfs_err("jfs_mount failed w/return code = %d", rc);
 490                 }
 491                 goto out_mount_failed;
 492         }
 493         if (sb->s_flags & MS_RDONLY)
 494                 sbi->log = NULL;
 495         else {
 496                 rc = jfs_mount_rw(sb, 0);
 497                 if (rc) {
 498                         if (!silent) {
 499                                 jfs_err("jfs_mount_rw failed, return code = %d",
 500                                         rc);
 501                         }
 502                         goto out_no_rw;
 503                 }
 504         }
 505
 506         sb->s_magic = JFS_SUPER_MAGIC;
 507
 508         inode = jfs_iget(sb, ROOT_I);
 509         if (IS_ERR(inode)) {
 510                 ret = PTR_ERR(inode);
 511                 goto out_no_rw;
 512         }
 513         sb->s_root = d_alloc_root(inode);
 514         if (!sb->s_root)
 515                 goto out_no_root;
 516
 517         if (sbi->mntflag & JFS_OS2)
 518                 sb->s_root->d_op = &jfs_ci_dentry_operations;
 519
 520         /* logical blocks are represented by 40 bits in pxd_t, etc. */
 521         sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
 522 #if BITS_PER_LONG == 32
 523         /*
 524          * Page cache is indexed by long.
 525          * I would use MAX_LFS_FILESIZE, but it's only half as big
 526          */
 527         sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, sb->s_maxbytes);
 528 #endif
 529         sb->s_time_gran = 1;
 530         return 0;
 531
 532 out_no_root:
 533         jfs_err("jfs_read_super: get root dentry failed");
 534         iput(inode);
 535
 536 out_no_rw:
 537         rc = jfs_umount(sb);
 538         if (rc) {
 539                 jfs_err("jfs_umount failed with return code %d", rc);
 540         }
 541 out_mount_failed:
 542         filemap_write_and_wait(sbi->direct_inode->i_mapping);
 543         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
 544         make_bad_inode(sbi->direct_inode);
 545         iput(sbi->direct_inode);
 546         sbi->direct_inode = NULL;
 547 out_kfree:
 548         if (sbi->nls_tab)
 549                 unload_nls(sbi->nls_tab);
 550         kfree(sbi);
 551         return ret;
 552 }
 553
 554 static int jfs_freeze(struct super_block *sb)
 555 {
 556         struct jfs_sb_info *sbi = JFS_SBI(sb);
 557         struct jfs_log *log = sbi->log;
 558
 559         if (!(sb->s_flags & MS_RDONLY)) {
 560                 txQuiesce(sb);
 561                 lmLogShutdown(log);
 562                 updateSuper(sb, FM_CLEAN);
 563         }
 564         return 0;
 565 }
 566
 567 static int jfs_unfreeze(struct super_block *sb)
 568 {
 569         struct jfs_sb_info *sbi = JFS_SBI(sb);
 570         struct jfs_log *log = sbi->log;
 571         int rc = 0;
 572
 573         if (!(sb->s_flags & MS_RDONLY)) {
 574                 updateSuper(sb, FM_MOUNT);
 575                 if ((rc = lmLogInit(log)))
 576                         jfs_err("jfs_unlock failed with return code %d", rc);
 577                 else
 578                         txResume(sb);
 579         }
 580         return 0;
 581 }
 582
 583 static int jfs_get_sb(struct file_system_type *fs_type,
 584         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 585 {
 586         return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super,
 587                            mnt);
 588 }
 589
 590 static int jfs_sync_fs(struct super_block *sb, int wait)
 591 {
 592         struct jfs_log *log = JFS_SBI(sb)->log;
 593
 594         /* log == NULL indicates read-only mount */
 595         if (log) {
 596                 jfs_flush_journal(log, wait);
 597                 jfs_syncpt(log, 0);
 598         }
 599
 600         return 0;
 601 }
 602
 603 static int jfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
 604 {
 605         struct jfs_sb_info *sbi = JFS_SBI(vfs->mnt_sb);
 606
 607         if (sbi->uid != -1)
 608                 seq_printf(seq, ",uid=%d", sbi->uid);
 609         if (sbi->gid != -1)
 610                 seq_printf(seq, ",gid=%d", sbi->gid);
 611         if (sbi->umask != -1)
 612                 seq_printf(seq, ",umask=%03o", sbi->umask);
 613         if (sbi->flag & JFS_NOINTEGRITY)
 614                 seq_puts(seq, ",nointegrity");
 615         if (sbi->nls_tab)
 616                 seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
 617         if (sbi->flag & JFS_ERR_CONTINUE)
 618                 seq_printf(seq, ",errors=continue");
 619         if (sbi->flag & JFS_ERR_PANIC)
 620                 seq_printf(seq, ",errors=panic");
 621
 622 #ifdef CONFIG_QUOTA
 623         if (sbi->flag & JFS_USRQUOTA)
 624                 seq_puts(seq, ",usrquota");
 625
 626         if (sbi->flag & JFS_GRPQUOTA)
 627                 seq_puts(seq, ",grpquota");
 628 #endif
 629
 630         return 0;
 631 }
 632
 633 #ifdef CONFIG_QUOTA
 634
 635 /* Read data from quotafile - avoid pagecache and such because we cannot afford
 636  * acquiring the locks... As quota files are never truncated and quota code
 637  * itself serializes the operations (and noone else should touch the files)
 638  * we don't have to be afraid of races */
 639 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
 640                               size_t len, loff_t off)
 641 {
 642         struct inode *inode = sb_dqopt(sb)->files[type];
 643         sector_t blk = off >> sb->s_blocksize_bits;
 644         int err = 0;
 645         int offset = off & (sb->s_blocksize - 1);
 646         int tocopy;
 647         size_t toread;
 648         struct buffer_head tmp_bh;
 649         struct buffer_head *bh;
 650         loff_t i_size = i_size_read(inode);
 651
 652         if (off > i_size)
 653                 return 0;
 654         if (off+len > i_size)
 655                 len = i_size-off;
 656         toread = len;
 657         while (toread > 0) {
 658                 tocopy = sb->s_blocksize - offset < toread ?
 659                                 sb->s_blocksize - offset : toread;
 660
 661                 tmp_bh.b_state = 0;
 662                 tmp_bh.b_size = 1 << inode->i_blkbits;
 663                 err = jfs_get_block(inode, blk, &tmp_bh, 0);
 664                 if (err)
 665                         return err;
 666                 if (!buffer_mapped(&tmp_bh))    /* A hole? */
 667                         memset(data, 0, tocopy);
 668                 else {
 669                         bh = sb_bread(sb, tmp_bh.b_blocknr);
 670                         if (!bh)
 671                                 return -EIO;
 672                         memcpy(data, bh->b_data+offset, tocopy);
 673                         brelse(bh);
 674                 }
 675                 offset = 0;
 676                 toread -= tocopy;
 677                 data += tocopy;
 678                 blk++;
 679         }
 680         return len;
 681 }
 682
 683 /* Write to quotafile */
 684 static ssize_t jfs_quota_write(struct super_block *sb, int type,
 685                                const char *data, size_t len, loff_t off)
 686 {
 687         struct inode *inode = sb_dqopt(sb)->files[type];
 688         sector_t blk = off >> sb->s_blocksize_bits;
 689         int err = 0;
 690         int offset = off & (sb->s_blocksize - 1);
 691         int tocopy;
 692         size_t towrite = len;
 693         struct buffer_head tmp_bh;
 694         struct buffer_head *bh;
 695
 696         mutex_lock(&inode->i_mutex);
 697         while (towrite > 0) {
 698                 tocopy = sb->s_blocksize - offset < towrite ?
 699                                 sb->s_blocksize - offset : towrite;
 700
 701                 tmp_bh.b_state = 0;
 702                 tmp_bh.b_size = 1 << inode->i_blkbits;
 703                 err = jfs_get_block(inode, blk, &tmp_bh, 1);
 704                 if (err)
 705                         goto out;
 706                 if (offset || tocopy != sb->s_blocksize)
 707                         bh = sb_bread(sb, tmp_bh.b_blocknr);
 708                 else
 709                         bh = sb_getblk(sb, tmp_bh.b_blocknr);
 710                 if (!bh) {
 711                         err = -EIO;
 712                         goto out;
 713                 }
 714                 lock_buffer(bh);
 715                 memcpy(bh->b_data+offset, data, tocopy);
 716                 flush_dcache_page(bh->b_page);
 717                 set_buffer_uptodate(bh);
 718                 mark_buffer_dirty(bh);
 719                 unlock_buffer(bh);
 720                 brelse(bh);
 721                 offset = 0;
 722                 towrite -= tocopy;
 723                 data += tocopy;
 724                 blk++;
 725         }
 726 out:
 727         if (len == towrite) {
 728                 mutex_unlock(&inode->i_mutex);
 729                 return err;
 730         }
 731         if (inode->i_size < off+len-towrite)
 732                 i_size_write(inode, off+len-towrite);
 733         inode->i_version++;
 734         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 735         mark_inode_dirty(inode);
 736         mutex_unlock(&inode->i_mutex);
 737         return len - towrite;
 738 }
 739
 740 #endif
 741
 742 static const struct super_operations jfs_super_operations = {
 743         .alloc_inode    = jfs_alloc_inode,
 744         .destroy_inode  = jfs_destroy_inode,
 745         .dirty_inode    = jfs_dirty_inode,
 746         .write_inode    = jfs_write_inode,
 747         .delete_inode   = jfs_delete_inode,
 748         .put_super      = jfs_put_super,
 749         .sync_fs        = jfs_sync_fs,
 750         .freeze_fs      = jfs_freeze,
 751         .unfreeze_fs    = jfs_unfreeze,
 752         .statfs         = jfs_statfs,
 753         .remount_fs     = jfs_remount,
 754         .show_options   = jfs_show_options,
 755 #ifdef CONFIG_QUOTA
 756         .quota_read     = jfs_quota_read,
 757         .quota_write    = jfs_quota_write,
 758 #endif
 759 };
 760
 761 static const struct export_operations jfs_export_operations = {
 762         .fh_to_dentry   = jfs_fh_to_dentry,
 763         .fh_to_parent   = jfs_fh_to_parent,
 764         .get_parent     = jfs_get_parent,
 765 };
 766
 767 static struct file_system_type jfs_fs_type = {
 768         .owner          = THIS_MODULE,
 769         .name           = "jfs",
 770         .get_sb         = jfs_get_sb,
 771         .kill_sb        = kill_block_super,
 772         .fs_flags       = FS_REQUIRES_DEV,
 773 };
 774
 775 static void init_once(void *foo)
 776 {
 777         struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
 778
 779         memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
 780         INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
 781         init_rwsem(&jfs_ip->rdwrlock);
 782         mutex_init(&jfs_ip->commit_mutex);
 783         init_rwsem(&jfs_ip->xattr_sem);
 784         spin_lock_init(&jfs_ip->ag_lock);
 785         jfs_ip->active_ag = -1;
 786         inode_init_once(&jfs_ip->vfs_inode);
 787 }
 788
 789 static int __init init_jfs_fs(void)
 790 {
 791         int i;
 792         int rc;
 793
 794         jfs_inode_cachep =
 795             kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
 796                             SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
 797                             init_once);
 798         if (jfs_inode_cachep == NULL)
 799                 return -ENOMEM;
 800
 801         /*
 802          * Metapage initialization
 803          */
 804         rc = metapage_init();
 805         if (rc) {
 806                 jfs_err("metapage_init failed w/rc = %d", rc);
 807                 goto free_slab;
 808         }
 809
 810         /*
 811          * Transaction Manager initialization
 812          */
 813         rc = txInit();
 814         if (rc) {
 815                 jfs_err("txInit failed w/rc = %d", rc);
 816                 goto free_metapage;
 817         }
 818
 819         /*
 820          * I/O completion thread (endio)
 821          */
 822         jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
 823         if (IS_ERR(jfsIOthread)) {
 824                 rc = PTR_ERR(jfsIOthread);
 825                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 826                 goto end_txmngr;
 827         }
 828
 829         if (commit_threads < 1)
 830                 commit_threads = num_online_cpus();
 831         if (commit_threads > MAX_COMMIT_THREADS)
 832                 commit_threads = MAX_COMMIT_THREADS;
 833
 834         for (i = 0; i < commit_threads; i++) {
 835                 jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL, "jfsCommit");
 836                 if (IS_ERR(jfsCommitThread[i])) {
 837                         rc = PTR_ERR(jfsCommitThread[i]);
 838                         jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 839                         commit_threads = i;
 840                         goto kill_committask;
 841                 }
 842         }
 843
 844         jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
 845         if (IS_ERR(jfsSyncThread)) {
 846                 rc = PTR_ERR(jfsSyncThread);
 847                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
 848                 goto kill_committask;
 849         }
 850
 851 #ifdef PROC_FS_JFS
 852         jfs_proc_init();
 853 #endif
 854
 855         return register_filesystem(&jfs_fs_type);
 856
 857 kill_committask:
 858         for (i = 0; i < commit_threads; i++)
 859                 kthread_stop(jfsCommitThread[i]);
 860         kthread_stop(jfsIOthread);
 861 end_txmngr:
 862         txExit();
 863 free_metapage:
 864         metapage_exit();
 865 free_slab:
 866         kmem_cache_destroy(jfs_inode_cachep);
 867         return rc;
 868 }
 869
 870 static void __exit exit_jfs_fs(void)
 871 {
 872         int i;
 873
 874         jfs_info("exit_jfs_fs called");
 875
 876         txExit();
 877         metapage_exit();
 878
 879         kthread_stop(jfsIOthread);
 880         for (i = 0; i < commit_threads; i++)
 881                 kthread_stop(jfsCommitThread[i]);
 882         kthread_stop(jfsSyncThread);
 883 #ifdef PROC_FS_JFS
 884         jfs_proc_clean();
 885 #endif
 886         unregister_filesystem(&jfs_fs_type);
 887         kmem_cache_destroy(jfs_inode_cachep);
 888 }
 889
 890 module_init(init_jfs_fs)
 891 module_exit(exit_jfs_fs)