Push BKL down into ->remount_fs()
[linux-3.10.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
132 #ifdef CONFIG_JFS_POSIX_ACL
133         if (ji->i_acl != JFS_ACL_NOT_CACHED) {
134                 posix_acl_release(ji->i_acl);
135                 ji->i_acl = JFS_ACL_NOT_CACHED;
136         }
137         if (ji->i_default_acl != JFS_ACL_NOT_CACHED) {
138                 posix_acl_release(ji->i_default_acl);
139                 ji->i_default_acl = JFS_ACL_NOT_CACHED;
140         }
141 #endif
142
143         kmem_cache_free(jfs_inode_cachep, ji);
144 }
145
146 static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
147 {
148         struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
149         s64 maxinodes;
150         struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
151
152         jfs_info("In jfs_statfs");
153         buf->f_type = JFS_SUPER_MAGIC;
154         buf->f_bsize = sbi->bsize;
155         buf->f_blocks = sbi->bmap->db_mapsize;
156         buf->f_bfree = sbi->bmap->db_nfree;
157         buf->f_bavail = sbi->bmap->db_nfree;
158         /*
159          * If we really return the number of allocated & free inodes, some
160          * applications will fail because they won't see enough free inodes.
161          * We'll try to calculate some guess as to how may inodes we can
162          * really allocate
163          *
164          * buf->f_files = atomic_read(&imap->im_numinos);
165          * buf->f_ffree = atomic_read(&imap->im_numfree);
166          */
167         maxinodes = min((s64) atomic_read(&imap->im_numinos) +
168                         ((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
169                          << L2INOSPEREXT), (s64) 0xffffffffLL);
170         buf->f_files = maxinodes;
171         buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
172                                     atomic_read(&imap->im_numfree));
173         buf->f_fsid.val[0] = (u32)crc32_le(0, sbi->uuid, sizeof(sbi->uuid)/2);
174         buf->f_fsid.val[1] = (u32)crc32_le(0, sbi->uuid + sizeof(sbi->uuid)/2,
175                                         sizeof(sbi->uuid)/2);
176
177         buf->f_namelen = JFS_NAME_MAX;
178         return 0;
179 }
180
181 static void jfs_put_super(struct super_block *sb)
182 {
183         struct jfs_sb_info *sbi = JFS_SBI(sb);
184         int rc;
185
186         jfs_info("In jfs_put_super");
187
188         lock_kernel();
189
190         rc = jfs_umount(sb);
191         if (rc)
192                 jfs_err("jfs_umount failed with return code %d", rc);
193         if (sbi->nls_tab)
194                 unload_nls(sbi->nls_tab);
195         sbi->nls_tab = NULL;
196
197         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
198         iput(sbi->direct_inode);
199         sbi->direct_inode = NULL;
200
201         kfree(sbi);
202
203         unlock_kernel();
204 }
205
206 enum {
207         Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
208         Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
209         Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask
210 };
211
212 static const match_table_t tokens = {
213         {Opt_integrity, "integrity"},
214         {Opt_nointegrity, "nointegrity"},
215         {Opt_iocharset, "iocharset=%s"},
216         {Opt_resize, "resize=%u"},
217         {Opt_resize_nosize, "resize"},
218         {Opt_errors, "errors=%s"},
219         {Opt_ignore, "noquota"},
220         {Opt_ignore, "quota"},
221         {Opt_usrquota, "usrquota"},
222         {Opt_grpquota, "grpquota"},
223         {Opt_uid, "uid=%u"},
224         {Opt_gid, "gid=%u"},
225         {Opt_umask, "umask=%u"},
226         {Opt_err, NULL}
227 };
228
229 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
230                          int *flag)
231 {
232         void *nls_map = (void *)-1;     /* -1: no change;  NULL: none */
233         char *p;
234         struct jfs_sb_info *sbi = JFS_SBI(sb);
235
236         *newLVSize = 0;
237
238         if (!options)
239                 return 1;
240
241         while ((p = strsep(&options, ",")) != NULL) {
242                 substring_t args[MAX_OPT_ARGS];
243                 int token;
244                 if (!*p)
245                         continue;
246
247                 token = match_token(p, tokens, args);
248                 switch (token) {
249                 case Opt_integrity:
250                         *flag &= ~JFS_NOINTEGRITY;
251                         break;
252                 case Opt_nointegrity:
253                         *flag |= JFS_NOINTEGRITY;
254                         break;
255                 case Opt_ignore:
256                         /* Silently ignore the quota options */
257                         /* Don't do anything ;-) */
258                         break;
259                 case Opt_iocharset:
260                         if (nls_map && nls_map != (void *) -1)
261                                 unload_nls(nls_map);
262                         if (!strcmp(args[0].from, "none"))
263                                 nls_map = NULL;
264                         else {
265                                 nls_map = load_nls(args[0].from);
266                                 if (!nls_map) {
267                                         printk(KERN_ERR
268                                                "JFS: charset not found\n");
269                                         goto cleanup;
270                                 }
271                         }
272                         break;
273                 case Opt_resize:
274                 {
275                         char *resize = args[0].from;
276                         *newLVSize = simple_strtoull(resize, &resize, 0);
277                         break;
278                 }
279                 case Opt_resize_nosize:
280                 {
281                         *newLVSize = sb->s_bdev->bd_inode->i_size >>
282                                 sb->s_blocksize_bits;
283                         if (*newLVSize == 0)
284                                 printk(KERN_ERR
285                                        "JFS: Cannot determine volume size\n");
286                         break;
287                 }
288                 case Opt_errors:
289                 {
290                         char *errors = args[0].from;
291                         if (!errors || !*errors)
292                                 goto cleanup;
293                         if (!strcmp(errors, "continue")) {
294                                 *flag &= ~JFS_ERR_REMOUNT_RO;
295                                 *flag &= ~JFS_ERR_PANIC;
296                                 *flag |= JFS_ERR_CONTINUE;
297                         } else if (!strcmp(errors, "remount-ro")) {
298                                 *flag &= ~JFS_ERR_CONTINUE;
299                                 *flag &= ~JFS_ERR_PANIC;
300                                 *flag |= JFS_ERR_REMOUNT_RO;
301                         } else if (!strcmp(errors, "panic")) {
302                                 *flag &= ~JFS_ERR_CONTINUE;
303                                 *flag &= ~JFS_ERR_REMOUNT_RO;
304                                 *flag |= JFS_ERR_PANIC;
305                         } else {
306                                 printk(KERN_ERR
307                                        "JFS: %s is an invalid error handler\n",
308                                        errors);
309                                 goto cleanup;
310                         }
311                         break;
312                 }
313
314 #ifdef CONFIG_QUOTA
315                 case Opt_quota:
316                 case Opt_usrquota:
317                         *flag |= JFS_USRQUOTA;
318                         break;
319                 case Opt_grpquota:
320                         *flag |= JFS_GRPQUOTA;
321                         break;
322 #else
323                 case Opt_usrquota:
324                 case Opt_grpquota:
325                 case Opt_quota:
326                         printk(KERN_ERR
327                                "JFS: quota operations not supported\n");
328                         break;
329 #endif
330                 case Opt_uid:
331                 {
332                         char *uid = args[0].from;
333                         sbi->uid = simple_strtoul(uid, &uid, 0);
334                         break;
335                 }
336                 case Opt_gid:
337                 {
338                         char *gid = args[0].from;
339                         sbi->gid = simple_strtoul(gid, &gid, 0);
340                         break;
341                 }
342                 case Opt_umask:
343                 {
344                         char *umask = args[0].from;
345                         sbi->umask = simple_strtoul(umask, &umask, 8);
346                         if (sbi->umask & ~0777) {
347                                 printk(KERN_ERR
348                                        "JFS: Invalid value of umask\n");
349                                 goto cleanup;
350                         }
351                         break;
352                 }
353                 default:
354                         printk("jfs: Unrecognized mount option \"%s\" "
355                                         " or missing value\n", p);
356                         goto cleanup;
357                 }
358         }
359
360         if (nls_map != (void *) -1) {
361                 /* Discard old (if remount) */
362                 if (sbi->nls_tab)
363                         unload_nls(sbi->nls_tab);
364                 sbi->nls_tab = nls_map;
365         }
366         return 1;
367
368 cleanup:
369         if (nls_map && nls_map != (void *) -1)
370                 unload_nls(nls_map);
371         return 0;
372 }
373
374 static int jfs_remount(struct super_block *sb, int *flags, char *data)
375 {
376         s64 newLVSize = 0;
377         int rc = 0;
378         int flag = JFS_SBI(sb)->flag;
379         int ret;
380
381         if (!parse_options(data, sb, &newLVSize, &flag)) {
382                 return -EINVAL;
383         }
384         lock_kernel();
385         if (newLVSize) {
386                 if (sb->s_flags & MS_RDONLY) {
387                         printk(KERN_ERR
388                   "JFS: resize requires volume to be mounted read-write\n");
389                         unlock_kernel();
390                         return -EROFS;
391                 }
392                 rc = jfs_extendfs(sb, newLVSize, 0);
393                 if (rc) {
394                         unlock_kernel();
395                         return rc;
396                 }
397         }
398
399         if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
400                 /*
401                  * Invalidate any previously read metadata.  fsck may have
402                  * changed the on-disk data since we mounted r/o
403                  */
404                 truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
405
406                 JFS_SBI(sb)->flag = flag;
407                 ret = jfs_mount_rw(sb, 1);
408                 unlock_kernel();
409                 return ret;
410         }
411         if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
412                 rc = jfs_umount_rw(sb);
413                 JFS_SBI(sb)->flag = flag;
414                 unlock_kernel();
415                 return rc;
416         }
417         if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
418                 if (!(sb->s_flags & MS_RDONLY)) {
419                         rc = jfs_umount_rw(sb);
420                         if (rc) {
421                                 unlock_kernel();
422                                 return rc;
423                         }
424                         JFS_SBI(sb)->flag = flag;
425                         ret = jfs_mount_rw(sb, 1);
426                         unlock_kernel();
427                         return ret;
428                 }
429         JFS_SBI(sb)->flag = flag;
430
431         unlock_kernel();
432         return 0;
433 }
434
435 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
436 {
437         struct jfs_sb_info *sbi;
438         struct inode *inode;
439         int rc;
440         s64 newLVSize = 0;
441         int flag, ret = -EINVAL;
442
443         jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
444
445         if (!new_valid_dev(sb->s_bdev->bd_dev))
446                 return -EOVERFLOW;
447
448         sbi = kzalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
449         if (!sbi)
450                 return -ENOMEM;
451         sb->s_fs_info = sbi;
452         sbi->sb = sb;
453         sbi->uid = sbi->gid = sbi->umask = -1;
454
455         /* initialize the mount flag and determine the default error handler */
456         flag = JFS_ERR_REMOUNT_RO;
457
458         if (!parse_options((char *) data, sb, &newLVSize, &flag)) {
459                 kfree(sbi);
460                 return -EINVAL;
461         }
462         sbi->flag = flag;
463
464 #ifdef CONFIG_JFS_POSIX_ACL
465         sb->s_flags |= MS_POSIXACL;
466 #endif
467
468         if (newLVSize) {
469                 printk(KERN_ERR "resize option for remount only\n");
470                 return -EINVAL;
471         }
472
473         /*
474          * Initialize blocksize to 4K.
475          */
476         sb_set_blocksize(sb, PSIZE);
477
478         /*
479          * Set method vectors.
480          */
481         sb->s_op = &jfs_super_operations;
482         sb->s_export_op = &jfs_export_operations;
483
484         /*
485          * Initialize direct-mapping inode/address-space
486          */
487         inode = new_inode(sb);
488         if (inode == NULL) {
489                 ret = -ENOMEM;
490                 goto out_kfree;
491         }
492         inode->i_ino = 0;
493         inode->i_nlink = 1;
494         inode->i_size = sb->s_bdev->bd_inode->i_size;
495         inode->i_mapping->a_ops = &jfs_metapage_aops;
496         insert_inode_hash(inode);
497         mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
498
499         sbi->direct_inode = inode;
500
501         rc = jfs_mount(sb);
502         if (rc) {
503                 if (!silent) {
504                         jfs_err("jfs_mount failed w/return code = %d", rc);
505                 }
506                 goto out_mount_failed;
507         }
508         if (sb->s_flags & MS_RDONLY)
509                 sbi->log = NULL;
510         else {
511                 rc = jfs_mount_rw(sb, 0);
512                 if (rc) {
513                         if (!silent) {
514                                 jfs_err("jfs_mount_rw failed, return code = %d",
515                                         rc);
516                         }
517                         goto out_no_rw;
518                 }
519         }
520
521         sb->s_magic = JFS_SUPER_MAGIC;
522
523         inode = jfs_iget(sb, ROOT_I);
524         if (IS_ERR(inode)) {
525                 ret = PTR_ERR(inode);
526                 goto out_no_rw;
527         }
528         sb->s_root = d_alloc_root(inode);
529         if (!sb->s_root)
530                 goto out_no_root;
531
532         if (sbi->mntflag & JFS_OS2)
533                 sb->s_root->d_op = &jfs_ci_dentry_operations;
534
535         /* logical blocks are represented by 40 bits in pxd_t, etc. */
536         sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
537 #if BITS_PER_LONG == 32
538         /*
539          * Page cache is indexed by long.
540          * I would use MAX_LFS_FILESIZE, but it's only half as big
541          */
542         sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, sb->s_maxbytes);
543 #endif
544         sb->s_time_gran = 1;
545         return 0;
546
547 out_no_root:
548         jfs_err("jfs_read_super: get root dentry failed");
549         iput(inode);
550
551 out_no_rw:
552         rc = jfs_umount(sb);
553         if (rc) {
554                 jfs_err("jfs_umount failed with return code %d", rc);
555         }
556 out_mount_failed:
557         filemap_write_and_wait(sbi->direct_inode->i_mapping);
558         truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
559         make_bad_inode(sbi->direct_inode);
560         iput(sbi->direct_inode);
561         sbi->direct_inode = NULL;
562 out_kfree:
563         if (sbi->nls_tab)
564                 unload_nls(sbi->nls_tab);
565         kfree(sbi);
566         return ret;
567 }
568
569 static int jfs_freeze(struct super_block *sb)
570 {
571         struct jfs_sb_info *sbi = JFS_SBI(sb);
572         struct jfs_log *log = sbi->log;
573
574         if (!(sb->s_flags & MS_RDONLY)) {
575                 txQuiesce(sb);
576                 lmLogShutdown(log);
577                 updateSuper(sb, FM_CLEAN);
578         }
579         return 0;
580 }
581
582 static int jfs_unfreeze(struct super_block *sb)
583 {
584         struct jfs_sb_info *sbi = JFS_SBI(sb);
585         struct jfs_log *log = sbi->log;
586         int rc = 0;
587
588         if (!(sb->s_flags & MS_RDONLY)) {
589                 updateSuper(sb, FM_MOUNT);
590                 if ((rc = lmLogInit(log)))
591                         jfs_err("jfs_unlock failed with return code %d", rc);
592                 else
593                         txResume(sb);
594         }
595         return 0;
596 }
597
598 static int jfs_get_sb(struct file_system_type *fs_type,
599         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
600 {
601         return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super,
602                            mnt);
603 }
604
605 static int jfs_sync_fs(struct super_block *sb, int wait)
606 {
607         struct jfs_log *log = JFS_SBI(sb)->log;
608
609         /* log == NULL indicates read-only mount */
610         if (log) {
611                 jfs_flush_journal(log, wait);
612                 jfs_syncpt(log, 0);
613         }
614
615         return 0;
616 }
617
618 static int jfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
619 {
620         struct jfs_sb_info *sbi = JFS_SBI(vfs->mnt_sb);
621
622         if (sbi->uid != -1)
623                 seq_printf(seq, ",uid=%d", sbi->uid);
624         if (sbi->gid != -1)
625                 seq_printf(seq, ",gid=%d", sbi->gid);
626         if (sbi->umask != -1)
627                 seq_printf(seq, ",umask=%03o", sbi->umask);
628         if (sbi->flag & JFS_NOINTEGRITY)
629                 seq_puts(seq, ",nointegrity");
630         if (sbi->nls_tab)
631                 seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
632         if (sbi->flag & JFS_ERR_CONTINUE)
633                 seq_printf(seq, ",errors=continue");
634         if (sbi->flag & JFS_ERR_PANIC)
635                 seq_printf(seq, ",errors=panic");
636
637 #ifdef CONFIG_QUOTA
638         if (sbi->flag & JFS_USRQUOTA)
639                 seq_puts(seq, ",usrquota");
640
641         if (sbi->flag & JFS_GRPQUOTA)
642                 seq_puts(seq, ",grpquota");
643 #endif
644
645         return 0;
646 }
647
648 #ifdef CONFIG_QUOTA
649
650 /* Read data from quotafile - avoid pagecache and such because we cannot afford
651  * acquiring the locks... As quota files are never truncated and quota code
652  * itself serializes the operations (and noone else should touch the files)
653  * we don't have to be afraid of races */
654 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
655                               size_t len, loff_t off)
656 {
657         struct inode *inode = sb_dqopt(sb)->files[type];
658         sector_t blk = off >> sb->s_blocksize_bits;
659         int err = 0;
660         int offset = off & (sb->s_blocksize - 1);
661         int tocopy;
662         size_t toread;
663         struct buffer_head tmp_bh;
664         struct buffer_head *bh;
665         loff_t i_size = i_size_read(inode);
666
667         if (off > i_size)
668                 return 0;
669         if (off+len > i_size)
670                 len = i_size-off;
671         toread = len;
672         while (toread > 0) {
673                 tocopy = sb->s_blocksize - offset < toread ?
674                                 sb->s_blocksize - offset : toread;
675
676                 tmp_bh.b_state = 0;
677                 tmp_bh.b_size = 1 << inode->i_blkbits;
678                 err = jfs_get_block(inode, blk, &tmp_bh, 0);
679                 if (err)
680                         return err;
681                 if (!buffer_mapped(&tmp_bh))    /* A hole? */
682                         memset(data, 0, tocopy);
683                 else {
684                         bh = sb_bread(sb, tmp_bh.b_blocknr);
685                         if (!bh)
686                                 return -EIO;
687                         memcpy(data, bh->b_data+offset, tocopy);
688                         brelse(bh);
689                 }
690                 offset = 0;
691                 toread -= tocopy;
692                 data += tocopy;
693                 blk++;
694         }
695         return len;
696 }
697
698 /* Write to quotafile */
699 static ssize_t jfs_quota_write(struct super_block *sb, int type,
700                                const char *data, size_t len, loff_t off)
701 {
702         struct inode *inode = sb_dqopt(sb)->files[type];
703         sector_t blk = off >> sb->s_blocksize_bits;
704         int err = 0;
705         int offset = off & (sb->s_blocksize - 1);
706         int tocopy;
707         size_t towrite = len;
708         struct buffer_head tmp_bh;
709         struct buffer_head *bh;
710
711         mutex_lock(&inode->i_mutex);
712         while (towrite > 0) {
713                 tocopy = sb->s_blocksize - offset < towrite ?
714                                 sb->s_blocksize - offset : towrite;
715
716                 tmp_bh.b_state = 0;
717                 tmp_bh.b_size = 1 << inode->i_blkbits;
718                 err = jfs_get_block(inode, blk, &tmp_bh, 1);
719                 if (err)
720                         goto out;
721                 if (offset || tocopy != sb->s_blocksize)
722                         bh = sb_bread(sb, tmp_bh.b_blocknr);
723                 else
724                         bh = sb_getblk(sb, tmp_bh.b_blocknr);
725                 if (!bh) {
726                         err = -EIO;
727                         goto out;
728                 }
729                 lock_buffer(bh);
730                 memcpy(bh->b_data+offset, data, tocopy);
731                 flush_dcache_page(bh->b_page);
732                 set_buffer_uptodate(bh);
733                 mark_buffer_dirty(bh);
734                 unlock_buffer(bh);
735                 brelse(bh);
736                 offset = 0;
737                 towrite -= tocopy;
738                 data += tocopy;
739                 blk++;
740         }
741 out:
742         if (len == towrite) {
743                 mutex_unlock(&inode->i_mutex);
744                 return err;
745         }
746         if (inode->i_size < off+len-towrite)
747                 i_size_write(inode, off+len-towrite);
748         inode->i_version++;
749         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
750         mark_inode_dirty(inode);
751         mutex_unlock(&inode->i_mutex);
752         return len - towrite;
753 }
754
755 #endif
756
757 static const struct super_operations jfs_super_operations = {
758         .alloc_inode    = jfs_alloc_inode,
759         .destroy_inode  = jfs_destroy_inode,
760         .dirty_inode    = jfs_dirty_inode,
761         .write_inode    = jfs_write_inode,
762         .delete_inode   = jfs_delete_inode,
763         .put_super      = jfs_put_super,
764         .sync_fs        = jfs_sync_fs,
765         .freeze_fs      = jfs_freeze,
766         .unfreeze_fs    = jfs_unfreeze,
767         .statfs         = jfs_statfs,
768         .remount_fs     = jfs_remount,
769         .show_options   = jfs_show_options,
770 #ifdef CONFIG_QUOTA
771         .quota_read     = jfs_quota_read,
772         .quota_write    = jfs_quota_write,
773 #endif
774 };
775
776 static const struct export_operations jfs_export_operations = {
777         .fh_to_dentry   = jfs_fh_to_dentry,
778         .fh_to_parent   = jfs_fh_to_parent,
779         .get_parent     = jfs_get_parent,
780 };
781
782 static struct file_system_type jfs_fs_type = {
783         .owner          = THIS_MODULE,
784         .name           = "jfs",
785         .get_sb         = jfs_get_sb,
786         .kill_sb        = kill_block_super,
787         .fs_flags       = FS_REQUIRES_DEV,
788 };
789
790 static void init_once(void *foo)
791 {
792         struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
793
794         memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
795         INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
796         init_rwsem(&jfs_ip->rdwrlock);
797         mutex_init(&jfs_ip->commit_mutex);
798         init_rwsem(&jfs_ip->xattr_sem);
799         spin_lock_init(&jfs_ip->ag_lock);
800         jfs_ip->active_ag = -1;
801 #ifdef CONFIG_JFS_POSIX_ACL
802         jfs_ip->i_acl = JFS_ACL_NOT_CACHED;
803         jfs_ip->i_default_acl = JFS_ACL_NOT_CACHED;
804 #endif
805         inode_init_once(&jfs_ip->vfs_inode);
806 }
807
808 static int __init init_jfs_fs(void)
809 {
810         int i;
811         int rc;
812
813         jfs_inode_cachep =
814             kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
815                             SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
816                             init_once);
817         if (jfs_inode_cachep == NULL)
818                 return -ENOMEM;
819
820         /*
821          * Metapage initialization
822          */
823         rc = metapage_init();
824         if (rc) {
825                 jfs_err("metapage_init failed w/rc = %d", rc);
826                 goto free_slab;
827         }
828
829         /*
830          * Transaction Manager initialization
831          */
832         rc = txInit();
833         if (rc) {
834                 jfs_err("txInit failed w/rc = %d", rc);
835                 goto free_metapage;
836         }
837
838         /*
839          * I/O completion thread (endio)
840          */
841         jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
842         if (IS_ERR(jfsIOthread)) {
843                 rc = PTR_ERR(jfsIOthread);
844                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
845                 goto end_txmngr;
846         }
847
848         if (commit_threads < 1)
849                 commit_threads = num_online_cpus();
850         if (commit_threads > MAX_COMMIT_THREADS)
851                 commit_threads = MAX_COMMIT_THREADS;
852
853         for (i = 0; i < commit_threads; i++) {
854                 jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL, "jfsCommit");
855                 if (IS_ERR(jfsCommitThread[i])) {
856                         rc = PTR_ERR(jfsCommitThread[i]);
857                         jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
858                         commit_threads = i;
859                         goto kill_committask;
860                 }
861         }
862
863         jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
864         if (IS_ERR(jfsSyncThread)) {
865                 rc = PTR_ERR(jfsSyncThread);
866                 jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
867                 goto kill_committask;
868         }
869
870 #ifdef PROC_FS_JFS
871         jfs_proc_init();
872 #endif
873
874         return register_filesystem(&jfs_fs_type);
875
876 kill_committask:
877         for (i = 0; i < commit_threads; i++)
878                 kthread_stop(jfsCommitThread[i]);
879         kthread_stop(jfsIOthread);
880 end_txmngr:
881         txExit();
882 free_metapage:
883         metapage_exit();
884 free_slab:
885         kmem_cache_destroy(jfs_inode_cachep);
886         return rc;
887 }
888
889 static void __exit exit_jfs_fs(void)
890 {
891         int i;
892
893         jfs_info("exit_jfs_fs called");
894
895         txExit();
896         metapage_exit();
897
898         kthread_stop(jfsIOthread);
899         for (i = 0; i < commit_threads; i++)
900                 kthread_stop(jfsCommitThread[i]);
901         kthread_stop(jfsSyncThread);
902 #ifdef PROC_FS_JFS
903         jfs_proc_clean();
904 #endif
905         unregister_filesystem(&jfs_fs_type);
906         kmem_cache_destroy(jfs_inode_cachep);
907 }
908
909 module_init(init_jfs_fs)
910 module_exit(exit_jfs_fs)