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