xref: /openbmc/linux/fs/jfs/super.c (revision 752beb5e)
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 <linux/slab.h>
34 #include <linux/uaccess.h>
35 #include <linux/seq_file.h>
36 #include <linux/blkdev.h>
37 
38 #include "jfs_incore.h"
39 #include "jfs_filsys.h"
40 #include "jfs_inode.h"
41 #include "jfs_metapage.h"
42 #include "jfs_superblock.h"
43 #include "jfs_dmap.h"
44 #include "jfs_imap.h"
45 #include "jfs_acl.h"
46 #include "jfs_debug.h"
47 #include "jfs_xattr.h"
48 #include "jfs_dinode.h"
49 
50 MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
51 MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
52 MODULE_LICENSE("GPL");
53 
54 static struct kmem_cache *jfs_inode_cachep;
55 
56 static const struct super_operations jfs_super_operations;
57 static const struct export_operations jfs_export_operations;
58 static struct file_system_type jfs_fs_type;
59 
60 #define MAX_COMMIT_THREADS 64
61 static int commit_threads;
62 module_param(commit_threads, int, 0);
63 MODULE_PARM_DESC(commit_threads, "Number of commit threads");
64 
65 static struct task_struct *jfsCommitThread[MAX_COMMIT_THREADS];
66 struct task_struct *jfsIOthread;
67 struct task_struct *jfsSyncThread;
68 
69 #ifdef CONFIG_JFS_DEBUG
70 int jfsloglevel = JFS_LOGLEVEL_WARN;
71 module_param(jfsloglevel, int, 0644);
72 MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
73 #endif
74 
75 static void jfs_handle_error(struct super_block *sb)
76 {
77 	struct jfs_sb_info *sbi = JFS_SBI(sb);
78 
79 	if (sb_rdonly(sb))
80 		return;
81 
82 	updateSuper(sb, FM_DIRTY);
83 
84 	if (sbi->flag & JFS_ERR_PANIC)
85 		panic("JFS (device %s): panic forced after error\n",
86 			sb->s_id);
87 	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
88 		jfs_err("ERROR: (device %s): remounting filesystem as read-only",
89 			sb->s_id);
90 		sb->s_flags |= SB_RDONLY;
91 	}
92 
93 	/* nothing is done for continue beyond marking the superblock dirty */
94 }
95 
96 void jfs_error(struct super_block *sb, const char *fmt, ...)
97 {
98 	struct va_format vaf;
99 	va_list args;
100 
101 	va_start(args, fmt);
102 
103 	vaf.fmt = fmt;
104 	vaf.va = &args;
105 
106 	pr_err("ERROR: (device %s): %ps: %pV\n",
107 	       sb->s_id, __builtin_return_address(0), &vaf);
108 
109 	va_end(args);
110 
111 	jfs_handle_error(sb);
112 }
113 
114 static struct inode *jfs_alloc_inode(struct super_block *sb)
115 {
116 	struct jfs_inode_info *jfs_inode;
117 
118 	jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
119 	if (!jfs_inode)
120 		return NULL;
121 #ifdef CONFIG_QUOTA
122 	memset(&jfs_inode->i_dquot, 0, sizeof(jfs_inode->i_dquot));
123 #endif
124 	return &jfs_inode->vfs_inode;
125 }
126 
127 static void jfs_free_inode(struct inode *inode)
128 {
129 	kmem_cache_free(jfs_inode_cachep, JFS_IP(inode));
130 }
131 
132 static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
133 {
134 	struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
135 	s64 maxinodes;
136 	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
137 
138 	jfs_info("In jfs_statfs");
139 	buf->f_type = JFS_SUPER_MAGIC;
140 	buf->f_bsize = sbi->bsize;
141 	buf->f_blocks = sbi->bmap->db_mapsize;
142 	buf->f_bfree = sbi->bmap->db_nfree;
143 	buf->f_bavail = sbi->bmap->db_nfree;
144 	/*
145 	 * If we really return the number of allocated & free inodes, some
146 	 * applications will fail because they won't see enough free inodes.
147 	 * We'll try to calculate some guess as to how many inodes we can
148 	 * really allocate
149 	 *
150 	 * buf->f_files = atomic_read(&imap->im_numinos);
151 	 * buf->f_ffree = atomic_read(&imap->im_numfree);
152 	 */
153 	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
154 			((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
155 			 << L2INOSPEREXT), (s64) 0xffffffffLL);
156 	buf->f_files = maxinodes;
157 	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
158 				    atomic_read(&imap->im_numfree));
159 	buf->f_fsid.val[0] = crc32_le(0, (char *)&sbi->uuid,
160 				      sizeof(sbi->uuid)/2);
161 	buf->f_fsid.val[1] = crc32_le(0,
162 				      (char *)&sbi->uuid + sizeof(sbi->uuid)/2,
163 				      sizeof(sbi->uuid)/2);
164 
165 	buf->f_namelen = JFS_NAME_MAX;
166 	return 0;
167 }
168 
169 #ifdef CONFIG_QUOTA
170 static int jfs_quota_off(struct super_block *sb, int type);
171 static int jfs_quota_on(struct super_block *sb, int type, int format_id,
172 			const struct path *path);
173 
174 static void jfs_quota_off_umount(struct super_block *sb)
175 {
176 	int type;
177 
178 	for (type = 0; type < MAXQUOTAS; type++)
179 		jfs_quota_off(sb, type);
180 }
181 
182 static const struct quotactl_ops jfs_quotactl_ops = {
183 	.quota_on	= jfs_quota_on,
184 	.quota_off	= jfs_quota_off,
185 	.quota_sync	= dquot_quota_sync,
186 	.get_state	= dquot_get_state,
187 	.set_info	= dquot_set_dqinfo,
188 	.get_dqblk	= dquot_get_dqblk,
189 	.set_dqblk	= dquot_set_dqblk,
190 	.get_nextdqblk	= dquot_get_next_dqblk,
191 };
192 #else
193 static inline void jfs_quota_off_umount(struct super_block *sb)
194 {
195 }
196 #endif
197 
198 static void jfs_put_super(struct super_block *sb)
199 {
200 	struct jfs_sb_info *sbi = JFS_SBI(sb);
201 	int rc;
202 
203 	jfs_info("In jfs_put_super");
204 
205 	jfs_quota_off_umount(sb);
206 
207 	rc = jfs_umount(sb);
208 	if (rc)
209 		jfs_err("jfs_umount failed with return code %d", rc);
210 
211 	unload_nls(sbi->nls_tab);
212 
213 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
214 	iput(sbi->direct_inode);
215 
216 	kfree(sbi);
217 }
218 
219 enum {
220 	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
221 	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
222 	Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask,
223 	Opt_discard, Opt_nodiscard, Opt_discard_minblk
224 };
225 
226 static const match_table_t tokens = {
227 	{Opt_integrity, "integrity"},
228 	{Opt_nointegrity, "nointegrity"},
229 	{Opt_iocharset, "iocharset=%s"},
230 	{Opt_resize, "resize=%u"},
231 	{Opt_resize_nosize, "resize"},
232 	{Opt_errors, "errors=%s"},
233 	{Opt_ignore, "noquota"},
234 	{Opt_quota, "quota"},
235 	{Opt_usrquota, "usrquota"},
236 	{Opt_grpquota, "grpquota"},
237 	{Opt_uid, "uid=%u"},
238 	{Opt_gid, "gid=%u"},
239 	{Opt_umask, "umask=%u"},
240 	{Opt_discard, "discard"},
241 	{Opt_nodiscard, "nodiscard"},
242 	{Opt_discard_minblk, "discard=%u"},
243 	{Opt_err, NULL}
244 };
245 
246 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
247 			 int *flag)
248 {
249 	void *nls_map = (void *)-1;	/* -1: no change;  NULL: none */
250 	char *p;
251 	struct jfs_sb_info *sbi = JFS_SBI(sb);
252 
253 	*newLVSize = 0;
254 
255 	if (!options)
256 		return 1;
257 
258 	while ((p = strsep(&options, ",")) != NULL) {
259 		substring_t args[MAX_OPT_ARGS];
260 		int token;
261 		if (!*p)
262 			continue;
263 
264 		token = match_token(p, tokens, args);
265 		switch (token) {
266 		case Opt_integrity:
267 			*flag &= ~JFS_NOINTEGRITY;
268 			break;
269 		case Opt_nointegrity:
270 			*flag |= JFS_NOINTEGRITY;
271 			break;
272 		case Opt_ignore:
273 			/* Silently ignore the quota options */
274 			/* Don't do anything ;-) */
275 			break;
276 		case Opt_iocharset:
277 			if (nls_map && nls_map != (void *) -1)
278 				unload_nls(nls_map);
279 			if (!strcmp(args[0].from, "none"))
280 				nls_map = NULL;
281 			else {
282 				nls_map = load_nls(args[0].from);
283 				if (!nls_map) {
284 					pr_err("JFS: charset not found\n");
285 					goto cleanup;
286 				}
287 			}
288 			break;
289 		case Opt_resize:
290 		{
291 			char *resize = args[0].from;
292 			int rc = kstrtoll(resize, 0, newLVSize);
293 
294 			if (rc)
295 				goto cleanup;
296 			break;
297 		}
298 		case Opt_resize_nosize:
299 		{
300 			*newLVSize = i_size_read(sb->s_bdev->bd_inode) >>
301 				sb->s_blocksize_bits;
302 			if (*newLVSize == 0)
303 				pr_err("JFS: Cannot determine volume size\n");
304 			break;
305 		}
306 		case Opt_errors:
307 		{
308 			char *errors = args[0].from;
309 			if (!errors || !*errors)
310 				goto cleanup;
311 			if (!strcmp(errors, "continue")) {
312 				*flag &= ~JFS_ERR_REMOUNT_RO;
313 				*flag &= ~JFS_ERR_PANIC;
314 				*flag |= JFS_ERR_CONTINUE;
315 			} else if (!strcmp(errors, "remount-ro")) {
316 				*flag &= ~JFS_ERR_CONTINUE;
317 				*flag &= ~JFS_ERR_PANIC;
318 				*flag |= JFS_ERR_REMOUNT_RO;
319 			} else if (!strcmp(errors, "panic")) {
320 				*flag &= ~JFS_ERR_CONTINUE;
321 				*flag &= ~JFS_ERR_REMOUNT_RO;
322 				*flag |= JFS_ERR_PANIC;
323 			} else {
324 				pr_err("JFS: %s is an invalid error handler\n",
325 				       errors);
326 				goto cleanup;
327 			}
328 			break;
329 		}
330 
331 #ifdef CONFIG_QUOTA
332 		case Opt_quota:
333 		case Opt_usrquota:
334 			*flag |= JFS_USRQUOTA;
335 			break;
336 		case Opt_grpquota:
337 			*flag |= JFS_GRPQUOTA;
338 			break;
339 #else
340 		case Opt_usrquota:
341 		case Opt_grpquota:
342 		case Opt_quota:
343 			pr_err("JFS: quota operations not supported\n");
344 			break;
345 #endif
346 		case Opt_uid:
347 		{
348 			char *uid = args[0].from;
349 			uid_t val;
350 			int rc = kstrtouint(uid, 0, &val);
351 
352 			if (rc)
353 				goto cleanup;
354 			sbi->uid = make_kuid(current_user_ns(), val);
355 			if (!uid_valid(sbi->uid))
356 				goto cleanup;
357 			break;
358 		}
359 
360 		case Opt_gid:
361 		{
362 			char *gid = args[0].from;
363 			gid_t val;
364 			int rc = kstrtouint(gid, 0, &val);
365 
366 			if (rc)
367 				goto cleanup;
368 			sbi->gid = make_kgid(current_user_ns(), val);
369 			if (!gid_valid(sbi->gid))
370 				goto cleanup;
371 			break;
372 		}
373 
374 		case Opt_umask:
375 		{
376 			char *umask = args[0].from;
377 			int rc = kstrtouint(umask, 8, &sbi->umask);
378 
379 			if (rc)
380 				goto cleanup;
381 			if (sbi->umask & ~0777) {
382 				pr_err("JFS: Invalid value of umask\n");
383 				goto cleanup;
384 			}
385 			break;
386 		}
387 
388 		case Opt_discard:
389 		{
390 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
391 			/* if set to 1, even copying files will cause
392 			 * trimming :O
393 			 * -> user has more control over the online trimming
394 			 */
395 			sbi->minblks_trim = 64;
396 			if (blk_queue_discard(q))
397 				*flag |= JFS_DISCARD;
398 			else
399 				pr_err("JFS: discard option not supported on device\n");
400 			break;
401 		}
402 
403 		case Opt_nodiscard:
404 			*flag &= ~JFS_DISCARD;
405 			break;
406 
407 		case Opt_discard_minblk:
408 		{
409 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
410 			char *minblks_trim = args[0].from;
411 			int rc;
412 			if (blk_queue_discard(q)) {
413 				*flag |= JFS_DISCARD;
414 				rc = kstrtouint(minblks_trim, 0,
415 						&sbi->minblks_trim);
416 				if (rc)
417 					goto cleanup;
418 			} else
419 				pr_err("JFS: discard option not supported on device\n");
420 			break;
421 		}
422 
423 		default:
424 			printk("jfs: Unrecognized mount option \"%s\" or missing value\n",
425 			       p);
426 			goto cleanup;
427 		}
428 	}
429 
430 	if (nls_map != (void *) -1) {
431 		/* Discard old (if remount) */
432 		unload_nls(sbi->nls_tab);
433 		sbi->nls_tab = nls_map;
434 	}
435 	return 1;
436 
437 cleanup:
438 	if (nls_map && nls_map != (void *) -1)
439 		unload_nls(nls_map);
440 	return 0;
441 }
442 
443 static int jfs_remount(struct super_block *sb, int *flags, char *data)
444 {
445 	s64 newLVSize = 0;
446 	int rc = 0;
447 	int flag = JFS_SBI(sb)->flag;
448 	int ret;
449 
450 	sync_filesystem(sb);
451 	if (!parse_options(data, sb, &newLVSize, &flag))
452 		return -EINVAL;
453 
454 	if (newLVSize) {
455 		if (sb_rdonly(sb)) {
456 			pr_err("JFS: resize requires volume to be mounted read-write\n");
457 			return -EROFS;
458 		}
459 		rc = jfs_extendfs(sb, newLVSize, 0);
460 		if (rc)
461 			return rc;
462 	}
463 
464 	if (sb_rdonly(sb) && !(*flags & SB_RDONLY)) {
465 		/*
466 		 * Invalidate any previously read metadata.  fsck may have
467 		 * changed the on-disk data since we mounted r/o
468 		 */
469 		truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
470 
471 		JFS_SBI(sb)->flag = flag;
472 		ret = jfs_mount_rw(sb, 1);
473 
474 		/* mark the fs r/w for quota activity */
475 		sb->s_flags &= ~SB_RDONLY;
476 
477 		dquot_resume(sb, -1);
478 		return ret;
479 	}
480 	if (!sb_rdonly(sb) && (*flags & SB_RDONLY)) {
481 		rc = dquot_suspend(sb, -1);
482 		if (rc < 0)
483 			return rc;
484 		rc = jfs_umount_rw(sb);
485 		JFS_SBI(sb)->flag = flag;
486 		return rc;
487 	}
488 	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
489 		if (!sb_rdonly(sb)) {
490 			rc = jfs_umount_rw(sb);
491 			if (rc)
492 				return rc;
493 
494 			JFS_SBI(sb)->flag = flag;
495 			ret = jfs_mount_rw(sb, 1);
496 			return ret;
497 		}
498 	JFS_SBI(sb)->flag = flag;
499 
500 	return 0;
501 }
502 
503 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
504 {
505 	struct jfs_sb_info *sbi;
506 	struct inode *inode;
507 	int rc;
508 	s64 newLVSize = 0;
509 	int flag, ret = -EINVAL;
510 
511 	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
512 
513 	sbi = kzalloc(sizeof(struct jfs_sb_info), GFP_KERNEL);
514 	if (!sbi)
515 		return -ENOMEM;
516 
517 	sb->s_fs_info = sbi;
518 	sb->s_max_links = JFS_LINK_MAX;
519 	sbi->sb = sb;
520 	sbi->uid = INVALID_UID;
521 	sbi->gid = INVALID_GID;
522 	sbi->umask = -1;
523 
524 	/* initialize the mount flag and determine the default error handler */
525 	flag = JFS_ERR_REMOUNT_RO;
526 
527 	if (!parse_options((char *) data, sb, &newLVSize, &flag))
528 		goto out_kfree;
529 	sbi->flag = flag;
530 
531 #ifdef CONFIG_JFS_POSIX_ACL
532 	sb->s_flags |= SB_POSIXACL;
533 #endif
534 
535 	if (newLVSize) {
536 		pr_err("resize option for remount only\n");
537 		goto out_kfree;
538 	}
539 
540 	/*
541 	 * Initialize blocksize to 4K.
542 	 */
543 	sb_set_blocksize(sb, PSIZE);
544 
545 	/*
546 	 * Set method vectors.
547 	 */
548 	sb->s_op = &jfs_super_operations;
549 	sb->s_export_op = &jfs_export_operations;
550 	sb->s_xattr = jfs_xattr_handlers;
551 #ifdef CONFIG_QUOTA
552 	sb->dq_op = &dquot_operations;
553 	sb->s_qcop = &jfs_quotactl_ops;
554 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
555 #endif
556 
557 	/*
558 	 * Initialize direct-mapping inode/address-space
559 	 */
560 	inode = new_inode(sb);
561 	if (inode == NULL) {
562 		ret = -ENOMEM;
563 		goto out_unload;
564 	}
565 	inode->i_ino = 0;
566 	inode->i_size = i_size_read(sb->s_bdev->bd_inode);
567 	inode->i_mapping->a_ops = &jfs_metapage_aops;
568 	inode_fake_hash(inode);
569 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
570 
571 	sbi->direct_inode = inode;
572 
573 	rc = jfs_mount(sb);
574 	if (rc) {
575 		if (!silent)
576 			jfs_err("jfs_mount failed w/return code = %d", rc);
577 		goto out_mount_failed;
578 	}
579 	if (sb_rdonly(sb))
580 		sbi->log = NULL;
581 	else {
582 		rc = jfs_mount_rw(sb, 0);
583 		if (rc) {
584 			if (!silent) {
585 				jfs_err("jfs_mount_rw failed, return code = %d",
586 					rc);
587 			}
588 			goto out_no_rw;
589 		}
590 	}
591 
592 	sb->s_magic = JFS_SUPER_MAGIC;
593 
594 	if (sbi->mntflag & JFS_OS2)
595 		sb->s_d_op = &jfs_ci_dentry_operations;
596 
597 	inode = jfs_iget(sb, ROOT_I);
598 	if (IS_ERR(inode)) {
599 		ret = PTR_ERR(inode);
600 		goto out_no_rw;
601 	}
602 	sb->s_root = d_make_root(inode);
603 	if (!sb->s_root)
604 		goto out_no_root;
605 
606 	/* logical blocks are represented by 40 bits in pxd_t, etc.
607 	 * and page cache is indexed by long
608 	 */
609 	sb->s_maxbytes = min(((loff_t)sb->s_blocksize) << 40, MAX_LFS_FILESIZE);
610 	sb->s_time_gran = 1;
611 	return 0;
612 
613 out_no_root:
614 	jfs_err("jfs_read_super: get root dentry failed");
615 
616 out_no_rw:
617 	rc = jfs_umount(sb);
618 	if (rc)
619 		jfs_err("jfs_umount failed with return code %d", rc);
620 out_mount_failed:
621 	filemap_write_and_wait(sbi->direct_inode->i_mapping);
622 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
623 	make_bad_inode(sbi->direct_inode);
624 	iput(sbi->direct_inode);
625 	sbi->direct_inode = NULL;
626 out_unload:
627 	unload_nls(sbi->nls_tab);
628 out_kfree:
629 	kfree(sbi);
630 	return ret;
631 }
632 
633 static int jfs_freeze(struct super_block *sb)
634 {
635 	struct jfs_sb_info *sbi = JFS_SBI(sb);
636 	struct jfs_log *log = sbi->log;
637 	int rc = 0;
638 
639 	if (!sb_rdonly(sb)) {
640 		txQuiesce(sb);
641 		rc = lmLogShutdown(log);
642 		if (rc) {
643 			jfs_error(sb, "lmLogShutdown failed\n");
644 
645 			/* let operations fail rather than hang */
646 			txResume(sb);
647 
648 			return rc;
649 		}
650 		rc = updateSuper(sb, FM_CLEAN);
651 		if (rc) {
652 			jfs_err("jfs_freeze: updateSuper failed");
653 			/*
654 			 * Don't fail here. Everything succeeded except
655 			 * marking the superblock clean, so there's really
656 			 * no harm in leaving it frozen for now.
657 			 */
658 		}
659 	}
660 	return 0;
661 }
662 
663 static int jfs_unfreeze(struct super_block *sb)
664 {
665 	struct jfs_sb_info *sbi = JFS_SBI(sb);
666 	struct jfs_log *log = sbi->log;
667 	int rc = 0;
668 
669 	if (!sb_rdonly(sb)) {
670 		rc = updateSuper(sb, FM_MOUNT);
671 		if (rc) {
672 			jfs_error(sb, "updateSuper failed\n");
673 			goto out;
674 		}
675 		rc = lmLogInit(log);
676 		if (rc)
677 			jfs_error(sb, "lmLogInit failed\n");
678 out:
679 		txResume(sb);
680 	}
681 	return rc;
682 }
683 
684 static struct dentry *jfs_do_mount(struct file_system_type *fs_type,
685 	int flags, const char *dev_name, void *data)
686 {
687 	return mount_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
688 }
689 
690 static int jfs_sync_fs(struct super_block *sb, int wait)
691 {
692 	struct jfs_log *log = JFS_SBI(sb)->log;
693 
694 	/* log == NULL indicates read-only mount */
695 	if (log) {
696 		/*
697 		 * Write quota structures to quota file, sync_blockdev() will
698 		 * write them to disk later
699 		 */
700 		dquot_writeback_dquots(sb, -1);
701 		jfs_flush_journal(log, wait);
702 		jfs_syncpt(log, 0);
703 	}
704 
705 	return 0;
706 }
707 
708 static int jfs_show_options(struct seq_file *seq, struct dentry *root)
709 {
710 	struct jfs_sb_info *sbi = JFS_SBI(root->d_sb);
711 
712 	if (uid_valid(sbi->uid))
713 		seq_printf(seq, ",uid=%d", from_kuid(&init_user_ns, sbi->uid));
714 	if (gid_valid(sbi->gid))
715 		seq_printf(seq, ",gid=%d", from_kgid(&init_user_ns, sbi->gid));
716 	if (sbi->umask != -1)
717 		seq_printf(seq, ",umask=%03o", sbi->umask);
718 	if (sbi->flag & JFS_NOINTEGRITY)
719 		seq_puts(seq, ",nointegrity");
720 	if (sbi->flag & JFS_DISCARD)
721 		seq_printf(seq, ",discard=%u", sbi->minblks_trim);
722 	if (sbi->nls_tab)
723 		seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
724 	if (sbi->flag & JFS_ERR_CONTINUE)
725 		seq_printf(seq, ",errors=continue");
726 	if (sbi->flag & JFS_ERR_PANIC)
727 		seq_printf(seq, ",errors=panic");
728 
729 #ifdef CONFIG_QUOTA
730 	if (sbi->flag & JFS_USRQUOTA)
731 		seq_puts(seq, ",usrquota");
732 
733 	if (sbi->flag & JFS_GRPQUOTA)
734 		seq_puts(seq, ",grpquota");
735 #endif
736 
737 	return 0;
738 }
739 
740 #ifdef CONFIG_QUOTA
741 
742 /* Read data from quotafile - avoid pagecache and such because we cannot afford
743  * acquiring the locks... As quota files are never truncated and quota code
744  * itself serializes the operations (and no one else should touch the files)
745  * we don't have to be afraid of races */
746 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
747 			      size_t len, loff_t off)
748 {
749 	struct inode *inode = sb_dqopt(sb)->files[type];
750 	sector_t blk = off >> sb->s_blocksize_bits;
751 	int err = 0;
752 	int offset = off & (sb->s_blocksize - 1);
753 	int tocopy;
754 	size_t toread;
755 	struct buffer_head tmp_bh;
756 	struct buffer_head *bh;
757 	loff_t i_size = i_size_read(inode);
758 
759 	if (off > i_size)
760 		return 0;
761 	if (off+len > i_size)
762 		len = i_size-off;
763 	toread = len;
764 	while (toread > 0) {
765 		tocopy = sb->s_blocksize - offset < toread ?
766 				sb->s_blocksize - offset : toread;
767 
768 		tmp_bh.b_state = 0;
769 		tmp_bh.b_size = i_blocksize(inode);
770 		err = jfs_get_block(inode, blk, &tmp_bh, 0);
771 		if (err)
772 			return err;
773 		if (!buffer_mapped(&tmp_bh))	/* A hole? */
774 			memset(data, 0, tocopy);
775 		else {
776 			bh = sb_bread(sb, tmp_bh.b_blocknr);
777 			if (!bh)
778 				return -EIO;
779 			memcpy(data, bh->b_data+offset, tocopy);
780 			brelse(bh);
781 		}
782 		offset = 0;
783 		toread -= tocopy;
784 		data += tocopy;
785 		blk++;
786 	}
787 	return len;
788 }
789 
790 /* Write to quotafile */
791 static ssize_t jfs_quota_write(struct super_block *sb, int type,
792 			       const char *data, size_t len, loff_t off)
793 {
794 	struct inode *inode = sb_dqopt(sb)->files[type];
795 	sector_t blk = off >> sb->s_blocksize_bits;
796 	int err = 0;
797 	int offset = off & (sb->s_blocksize - 1);
798 	int tocopy;
799 	size_t towrite = len;
800 	struct buffer_head tmp_bh;
801 	struct buffer_head *bh;
802 
803 	inode_lock(inode);
804 	while (towrite > 0) {
805 		tocopy = sb->s_blocksize - offset < towrite ?
806 				sb->s_blocksize - offset : towrite;
807 
808 		tmp_bh.b_state = 0;
809 		tmp_bh.b_size = i_blocksize(inode);
810 		err = jfs_get_block(inode, blk, &tmp_bh, 1);
811 		if (err)
812 			goto out;
813 		if (offset || tocopy != sb->s_blocksize)
814 			bh = sb_bread(sb, tmp_bh.b_blocknr);
815 		else
816 			bh = sb_getblk(sb, tmp_bh.b_blocknr);
817 		if (!bh) {
818 			err = -EIO;
819 			goto out;
820 		}
821 		lock_buffer(bh);
822 		memcpy(bh->b_data+offset, data, tocopy);
823 		flush_dcache_page(bh->b_page);
824 		set_buffer_uptodate(bh);
825 		mark_buffer_dirty(bh);
826 		unlock_buffer(bh);
827 		brelse(bh);
828 		offset = 0;
829 		towrite -= tocopy;
830 		data += tocopy;
831 		blk++;
832 	}
833 out:
834 	if (len == towrite) {
835 		inode_unlock(inode);
836 		return err;
837 	}
838 	if (inode->i_size < off+len-towrite)
839 		i_size_write(inode, off+len-towrite);
840 	inode->i_mtime = inode->i_ctime = current_time(inode);
841 	mark_inode_dirty(inode);
842 	inode_unlock(inode);
843 	return len - towrite;
844 }
845 
846 static struct dquot **jfs_get_dquots(struct inode *inode)
847 {
848 	return JFS_IP(inode)->i_dquot;
849 }
850 
851 static int jfs_quota_on(struct super_block *sb, int type, int format_id,
852 			const struct path *path)
853 {
854 	int err;
855 	struct inode *inode;
856 
857 	err = dquot_quota_on(sb, type, format_id, path);
858 	if (err)
859 		return err;
860 
861 	inode = d_inode(path->dentry);
862 	inode_lock(inode);
863 	JFS_IP(inode)->mode2 |= JFS_NOATIME_FL | JFS_IMMUTABLE_FL;
864 	inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
865 			S_NOATIME | S_IMMUTABLE);
866 	inode_unlock(inode);
867 	mark_inode_dirty(inode);
868 
869 	return 0;
870 }
871 
872 static int jfs_quota_off(struct super_block *sb, int type)
873 {
874 	struct inode *inode = sb_dqopt(sb)->files[type];
875 	int err;
876 
877 	if (!inode || !igrab(inode))
878 		goto out;
879 
880 	err = dquot_quota_off(sb, type);
881 	if (err)
882 		goto out_put;
883 
884 	inode_lock(inode);
885 	JFS_IP(inode)->mode2 &= ~(JFS_NOATIME_FL | JFS_IMMUTABLE_FL);
886 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
887 	inode_unlock(inode);
888 	mark_inode_dirty(inode);
889 out_put:
890 	iput(inode);
891 	return err;
892 out:
893 	return dquot_quota_off(sb, type);
894 }
895 #endif
896 
897 static const struct super_operations jfs_super_operations = {
898 	.alloc_inode	= jfs_alloc_inode,
899 	.free_inode	= jfs_free_inode,
900 	.dirty_inode	= jfs_dirty_inode,
901 	.write_inode	= jfs_write_inode,
902 	.evict_inode	= jfs_evict_inode,
903 	.put_super	= jfs_put_super,
904 	.sync_fs	= jfs_sync_fs,
905 	.freeze_fs	= jfs_freeze,
906 	.unfreeze_fs	= jfs_unfreeze,
907 	.statfs		= jfs_statfs,
908 	.remount_fs	= jfs_remount,
909 	.show_options	= jfs_show_options,
910 #ifdef CONFIG_QUOTA
911 	.quota_read	= jfs_quota_read,
912 	.quota_write	= jfs_quota_write,
913 	.get_dquots	= jfs_get_dquots,
914 #endif
915 };
916 
917 static const struct export_operations jfs_export_operations = {
918 	.fh_to_dentry	= jfs_fh_to_dentry,
919 	.fh_to_parent	= jfs_fh_to_parent,
920 	.get_parent	= jfs_get_parent,
921 };
922 
923 static struct file_system_type jfs_fs_type = {
924 	.owner		= THIS_MODULE,
925 	.name		= "jfs",
926 	.mount		= jfs_do_mount,
927 	.kill_sb	= kill_block_super,
928 	.fs_flags	= FS_REQUIRES_DEV,
929 };
930 MODULE_ALIAS_FS("jfs");
931 
932 static void init_once(void *foo)
933 {
934 	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
935 
936 	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
937 	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
938 	init_rwsem(&jfs_ip->rdwrlock);
939 	mutex_init(&jfs_ip->commit_mutex);
940 	init_rwsem(&jfs_ip->xattr_sem);
941 	spin_lock_init(&jfs_ip->ag_lock);
942 	jfs_ip->active_ag = -1;
943 	inode_init_once(&jfs_ip->vfs_inode);
944 }
945 
946 static int __init init_jfs_fs(void)
947 {
948 	int i;
949 	int rc;
950 
951 	jfs_inode_cachep =
952 	    kmem_cache_create_usercopy("jfs_ip", sizeof(struct jfs_inode_info),
953 			0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|SLAB_ACCOUNT,
954 			offsetof(struct jfs_inode_info, i_inline), IDATASIZE,
955 			init_once);
956 	if (jfs_inode_cachep == NULL)
957 		return -ENOMEM;
958 
959 	/*
960 	 * Metapage initialization
961 	 */
962 	rc = metapage_init();
963 	if (rc) {
964 		jfs_err("metapage_init failed w/rc = %d", rc);
965 		goto free_slab;
966 	}
967 
968 	/*
969 	 * Transaction Manager initialization
970 	 */
971 	rc = txInit();
972 	if (rc) {
973 		jfs_err("txInit failed w/rc = %d", rc);
974 		goto free_metapage;
975 	}
976 
977 	/*
978 	 * I/O completion thread (endio)
979 	 */
980 	jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
981 	if (IS_ERR(jfsIOthread)) {
982 		rc = PTR_ERR(jfsIOthread);
983 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
984 		goto end_txmngr;
985 	}
986 
987 	if (commit_threads < 1)
988 		commit_threads = num_online_cpus();
989 	if (commit_threads > MAX_COMMIT_THREADS)
990 		commit_threads = MAX_COMMIT_THREADS;
991 
992 	for (i = 0; i < commit_threads; i++) {
993 		jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL,
994 						 "jfsCommit");
995 		if (IS_ERR(jfsCommitThread[i])) {
996 			rc = PTR_ERR(jfsCommitThread[i]);
997 			jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
998 			commit_threads = i;
999 			goto kill_committask;
1000 		}
1001 	}
1002 
1003 	jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
1004 	if (IS_ERR(jfsSyncThread)) {
1005 		rc = PTR_ERR(jfsSyncThread);
1006 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
1007 		goto kill_committask;
1008 	}
1009 
1010 #ifdef PROC_FS_JFS
1011 	jfs_proc_init();
1012 #endif
1013 
1014 	rc = register_filesystem(&jfs_fs_type);
1015 	if (!rc)
1016 		return 0;
1017 
1018 #ifdef PROC_FS_JFS
1019 	jfs_proc_clean();
1020 #endif
1021 	kthread_stop(jfsSyncThread);
1022 kill_committask:
1023 	for (i = 0; i < commit_threads; i++)
1024 		kthread_stop(jfsCommitThread[i]);
1025 	kthread_stop(jfsIOthread);
1026 end_txmngr:
1027 	txExit();
1028 free_metapage:
1029 	metapage_exit();
1030 free_slab:
1031 	kmem_cache_destroy(jfs_inode_cachep);
1032 	return rc;
1033 }
1034 
1035 static void __exit exit_jfs_fs(void)
1036 {
1037 	int i;
1038 
1039 	jfs_info("exit_jfs_fs called");
1040 
1041 	txExit();
1042 	metapage_exit();
1043 
1044 	kthread_stop(jfsIOthread);
1045 	for (i = 0; i < commit_threads; i++)
1046 		kthread_stop(jfsCommitThread[i]);
1047 	kthread_stop(jfsSyncThread);
1048 #ifdef PROC_FS_JFS
1049 	jfs_proc_clean();
1050 #endif
1051 	unregister_filesystem(&jfs_fs_type);
1052 
1053 	/*
1054 	 * Make sure all delayed rcu free inodes are flushed before we
1055 	 * destroy cache.
1056 	 */
1057 	rcu_barrier();
1058 	kmem_cache_destroy(jfs_inode_cachep);
1059 }
1060 
1061 module_init(init_jfs_fs)
1062 module_exit(exit_jfs_fs)
1063