d929a822a74e6410fd89727f4351e164f8e65ede
[linux-2.6.git] / 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, (u64)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)