xref: /openbmc/linux/fs/jfs/super.c (revision 545e4006)
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)
883