xref: /openbmc/linux/fs/jfs/super.c (revision c21b37f6)
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 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;
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 		goto out_kfree;
466 	inode->i_ino = 0;
467 	inode->i_nlink = 1;
468 	inode->i_size = sb->s_bdev->bd_inode->i_size;
469 	inode->i_mapping->a_ops = &jfs_metapage_aops;
470 	insert_inode_hash(inode);
471 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
472 
473 	sbi->direct_inode = inode;
474 
475 	rc = jfs_mount(sb);
476 	if (rc) {
477 		if (!silent) {
478 			jfs_err("jfs_mount failed w/return code = %d", rc);
479 		}
480 		goto out_mount_failed;
481 	}
482 	if (sb->s_flags & MS_RDONLY)
483 		sbi->log = NULL;
484 	else {
485 		rc = jfs_mount_rw(sb, 0);
486 		if (rc) {
487 			if (!silent) {
488 				jfs_err("jfs_mount_rw failed, return code = %d",
489 					rc);
490 			}
491 			goto out_no_rw;
492 		}
493 	}
494 
495 	sb->s_magic = JFS_SUPER_MAGIC;
496 
497 	inode = iget(sb, ROOT_I);
498 	if (!inode || is_bad_inode(inode))
499 		goto out_no_root;
500 	sb->s_root = d_alloc_root(inode);
501 	if (!sb->s_root)
502 		goto out_no_root;
503 
504 	if (sbi->mntflag & JFS_OS2)
505 		sb->s_root->d_op = &jfs_ci_dentry_operations;
506 
507 	/* logical blocks are represented by 40 bits in pxd_t, etc. */
508 	sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
509 #if BITS_PER_LONG == 32
510 	/*
511 	 * Page cache is indexed by long.
512 	 * I would use MAX_LFS_FILESIZE, but it's only half as big
513 	 */
514 	sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, sb->s_maxbytes);
515 #endif
516 	sb->s_time_gran = 1;
517 	return 0;
518 
519 out_no_root:
520 	jfs_err("jfs_read_super: get root inode failed");
521 	if (inode)
522 		iput(inode);
523 
524 out_no_rw:
525 	rc = jfs_umount(sb);
526 	if (rc) {
527 		jfs_err("jfs_umount failed with return code %d", rc);
528 	}
529 out_mount_failed:
530 	filemap_write_and_wait(sbi->direct_inode->i_mapping);
531 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
532 	make_bad_inode(sbi->direct_inode);
533 	iput(sbi->direct_inode);
534 	sbi->direct_inode = NULL;
535 out_kfree:
536 	if (sbi->nls_tab)
537 		unload_nls(sbi->nls_tab);
538 	kfree(sbi);
539 	return -EINVAL;
540 }
541 
542 static void jfs_write_super_lockfs(struct super_block *sb)
543 {
544 	struct jfs_sb_info *sbi = JFS_SBI(sb);
545 	struct jfs_log *log = sbi->log;
546 
547 	if (!(sb->s_flags & MS_RDONLY)) {
548 		txQuiesce(sb);
549 		lmLogShutdown(log);
550 		updateSuper(sb, FM_CLEAN);
551 	}
552 }
553 
554 static void jfs_unlockfs(struct super_block *sb)
555 {
556 	struct jfs_sb_info *sbi = JFS_SBI(sb);
557 	struct jfs_log *log = sbi->log;
558 	int rc = 0;
559 
560 	if (!(sb->s_flags & MS_RDONLY)) {
561 		updateSuper(sb, FM_MOUNT);
562 		if ((rc = lmLogInit(log)))
563 			jfs_err("jfs_unlock failed with return code %d", rc);
564 		else
565 			txResume(sb);
566 	}
567 }
568 
569 static int jfs_get_sb(struct file_system_type *fs_type,
570 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
571 {
572 	return get_sb_bdev(fs_type, flags, dev_name, data, jfs_fill_super,
573 			   mnt);
574 }
575 
576 static int jfs_sync_fs(struct super_block *sb, int wait)
577 {
578 	struct jfs_log *log = JFS_SBI(sb)->log;
579 
580 	/* log == NULL indicates read-only mount */
581 	if (log) {
582 		jfs_flush_journal(log, wait);
583 		jfs_syncpt(log, 0);
584 	}
585 
586 	return 0;
587 }
588 
589 static int jfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
590 {
591 	struct jfs_sb_info *sbi = JFS_SBI(vfs->mnt_sb);
592 
593 	if (sbi->uid != -1)
594 		seq_printf(seq, ",uid=%d", sbi->uid);
595 	if (sbi->gid != -1)
596 		seq_printf(seq, ",gid=%d", sbi->gid);
597 	if (sbi->umask != -1)
598 		seq_printf(seq, ",umask=%03o", sbi->umask);
599 	if (sbi->flag & JFS_NOINTEGRITY)
600 		seq_puts(seq, ",nointegrity");
601 
602 #ifdef CONFIG_QUOTA
603 	if (sbi->flag & JFS_USRQUOTA)
604 		seq_puts(seq, ",usrquota");
605 
606 	if (sbi->flag & JFS_GRPQUOTA)
607 		seq_puts(seq, ",grpquota");
608 #endif
609 
610 	return 0;
611 }
612 
613 #ifdef CONFIG_QUOTA
614 
615 /* Read data from quotafile - avoid pagecache and such because we cannot afford
616  * acquiring the locks... As quota files are never truncated and quota code
617  * itself serializes the operations (and noone else should touch the files)
618  * we don't have to be afraid of races */
619 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
620 			      size_t len, loff_t off)
621 {
622 	struct inode *inode = sb_dqopt(sb)->files[type];
623 	sector_t blk = off >> sb->s_blocksize_bits;
624 	int err = 0;
625 	int offset = off & (sb->s_blocksize - 1);
626 	int tocopy;
627 	size_t toread;
628 	struct buffer_head tmp_bh;
629 	struct buffer_head *bh;
630 	loff_t i_size = i_size_read(inode);
631 
632 	if (off > i_size)
633 		return 0;
634 	if (off+len > i_size)
635 		len = i_size-off;
636 	toread = len;
637 	while (toread > 0) {
638 		tocopy = sb->s_blocksize - offset < toread ?
639 				sb->s_blocksize - offset : toread;
640 
641 		tmp_bh.b_state = 0;
642 		tmp_bh.b_size = 1 << inode->i_blkbits;
643 		err = jfs_get_block(inode, blk, &tmp_bh, 0);
644 		if (err)
645 			return err;
646 		if (!buffer_mapped(&tmp_bh))	/* A hole? */
647 			memset(data, 0, tocopy);
648 		else {
649 			bh = sb_bread(sb, tmp_bh.b_blocknr);
650 			if (!bh)
651 				return -EIO;
652 			memcpy(data, bh->b_data+offset, tocopy);
653 			brelse(bh);
654 		}
655 		offset = 0;
656 		toread -= tocopy;
657 		data += tocopy;
658 		blk++;
659 	}
660 	return len;
661 }
662 
663 /* Write to quotafile */
664 static ssize_t jfs_quota_write(struct super_block *sb, int type,
665 			       const char *data, size_t len, loff_t off)
666 {
667 	struct inode *inode = sb_dqopt(sb)->files[type];
668 	sector_t blk = off >> sb->s_blocksize_bits;
669 	int err = 0;
670 	int offset = off & (sb->s_blocksize - 1);
671 	int tocopy;
672 	size_t towrite = len;
673 	struct buffer_head tmp_bh;
674 	struct buffer_head *bh;
675 
676 	mutex_lock(&inode->i_mutex);
677 	while (towrite > 0) {
678 		tocopy = sb->s_blocksize - offset < towrite ?
679 				sb->s_blocksize - offset : towrite;
680 
681 		tmp_bh.b_state = 0;
682 		tmp_bh.b_size = 1 << inode->i_blkbits;
683 		err = jfs_get_block(inode, blk, &tmp_bh, 1);
684 		if (err)
685 			goto out;
686 		if (offset || tocopy != sb->s_blocksize)
687 			bh = sb_bread(sb, tmp_bh.b_blocknr);
688 		else
689 			bh = sb_getblk(sb, tmp_bh.b_blocknr);
690 		if (!bh) {
691 			err = -EIO;
692 			goto out;
693 		}
694 		lock_buffer(bh);
695 		memcpy(bh->b_data+offset, data, tocopy);
696 		flush_dcache_page(bh->b_page);
697 		set_buffer_uptodate(bh);
698 		mark_buffer_dirty(bh);
699 		unlock_buffer(bh);
700 		brelse(bh);
701 		offset = 0;
702 		towrite -= tocopy;
703 		data += tocopy;
704 		blk++;
705 	}
706 out:
707 	if (len == towrite)
708 		return err;
709 	if (inode->i_size < off+len-towrite)
710 		i_size_write(inode, off+len-towrite);
711 	inode->i_version++;
712 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
713 	mark_inode_dirty(inode);
714 	mutex_unlock(&inode->i_mutex);
715 	return len - towrite;
716 }
717 
718 #endif
719 
720 static const struct super_operations jfs_super_operations = {
721 	.alloc_inode	= jfs_alloc_inode,
722 	.destroy_inode	= jfs_destroy_inode,
723 	.read_inode	= jfs_read_inode,
724 	.dirty_inode	= jfs_dirty_inode,
725 	.write_inode	= jfs_write_inode,
726 	.delete_inode	= jfs_delete_inode,
727 	.put_super	= jfs_put_super,
728 	.sync_fs	= jfs_sync_fs,
729 	.write_super_lockfs = jfs_write_super_lockfs,
730 	.unlockfs       = jfs_unlockfs,
731 	.statfs		= jfs_statfs,
732 	.remount_fs	= jfs_remount,
733 	.show_options	= jfs_show_options,
734 #ifdef CONFIG_QUOTA
735 	.quota_read	= jfs_quota_read,
736 	.quota_write	= jfs_quota_write,
737 #endif
738 };
739 
740 static struct export_operations jfs_export_operations = {
741 	.get_dentry	= jfs_get_dentry,
742 	.get_parent	= jfs_get_parent,
743 };
744 
745 static struct file_system_type jfs_fs_type = {
746 	.owner		= THIS_MODULE,
747 	.name		= "jfs",
748 	.get_sb		= jfs_get_sb,
749 	.kill_sb	= kill_block_super,
750 	.fs_flags	= FS_REQUIRES_DEV,
751 };
752 
753 static void init_once(void *foo, struct kmem_cache * cachep, unsigned long flags)
754 {
755 	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
756 
757 	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
758 	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
759 	init_rwsem(&jfs_ip->rdwrlock);
760 	mutex_init(&jfs_ip->commit_mutex);
761 	init_rwsem(&jfs_ip->xattr_sem);
762 	spin_lock_init(&jfs_ip->ag_lock);
763 	jfs_ip->active_ag = -1;
764 #ifdef CONFIG_JFS_POSIX_ACL
765 	jfs_ip->i_acl = JFS_ACL_NOT_CACHED;
766 	jfs_ip->i_default_acl = JFS_ACL_NOT_CACHED;
767 #endif
768 	inode_init_once(&jfs_ip->vfs_inode);
769 }
770 
771 static int __init init_jfs_fs(void)
772 {
773 	int i;
774 	int rc;
775 
776 	jfs_inode_cachep =
777 	    kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
778 			    SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
779 			    init_once);
780 	if (jfs_inode_cachep == NULL)
781 		return -ENOMEM;
782 
783 	/*
784 	 * Metapage initialization
785 	 */
786 	rc = metapage_init();
787 	if (rc) {
788 		jfs_err("metapage_init failed w/rc = %d", rc);
789 		goto free_slab;
790 	}
791 
792 	/*
793 	 * Transaction Manager initialization
794 	 */
795 	rc = txInit();
796 	if (rc) {
797 		jfs_err("txInit failed w/rc = %d", rc);
798 		goto free_metapage;
799 	}
800 
801 	/*
802 	 * I/O completion thread (endio)
803 	 */
804 	jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
805 	if (IS_ERR(jfsIOthread)) {
806 		rc = PTR_ERR(jfsIOthread);
807 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
808 		goto end_txmngr;
809 	}
810 
811 	if (commit_threads < 1)
812 		commit_threads = num_online_cpus();
813 	if (commit_threads > MAX_COMMIT_THREADS)
814 		commit_threads = MAX_COMMIT_THREADS;
815 
816 	for (i = 0; i < commit_threads; i++) {
817 		jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL, "jfsCommit");
818 		if (IS_ERR(jfsCommitThread[i])) {
819 			rc = PTR_ERR(jfsCommitThread[i]);
820 			jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
821 			commit_threads = i;
822 			goto kill_committask;
823 		}
824 	}
825 
826 	jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
827 	if (IS_ERR(jfsSyncThread)) {
828 		rc = PTR_ERR(jfsSyncThread);
829 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
830 		goto kill_committask;
831 	}
832 
833 #ifdef PROC_FS_JFS
834 	jfs_proc_init();
835 #endif
836 
837 	return register_filesystem(&jfs_fs_type);
838 
839 kill_committask:
840 	for (i = 0; i < commit_threads; i++)
841 		kthread_stop(jfsCommitThread[i]);
842 	kthread_stop(jfsIOthread);
843 end_txmngr:
844 	txExit();
845 free_metapage:
846 	metapage_exit();
847 free_slab:
848 	kmem_cache_destroy(jfs_inode_cachep);
849 	return rc;
850 }
851 
852 static void __exit exit_jfs_fs(void)
853 {
854 	int i;
855 
856 	jfs_info("exit_jfs_fs called");
857 
858 	txExit();
859 	metapage_exit();
860 
861 	kthread_stop(jfsIOthread);
862 	for (i = 0; i < commit_threads; i++)
863 		kthread_stop(jfsCommitThread[i]);
864 	kthread_stop(jfsSyncThread);
865 #ifdef PROC_FS_JFS
866 	jfs_proc_clean();
867 #endif
868 	unregister_filesystem(&jfs_fs_type);
869 	kmem_cache_destroy(jfs_inode_cachep);
870 }
871 
872 module_init(init_jfs_fs)
873 module_exit(exit_jfs_fs)
874