xref: /openbmc/linux/fs/jfs/super.c (revision 39b6f3aa)
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 <asm/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 
48 MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
49 MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
50 MODULE_LICENSE("GPL");
51 
52 static struct kmem_cache * jfs_inode_cachep;
53 
54 static const struct super_operations jfs_super_operations;
55 static const struct export_operations jfs_export_operations;
56 static struct file_system_type jfs_fs_type;
57 
58 #define MAX_COMMIT_THREADS 64
59 static int commit_threads = 0;
60 module_param(commit_threads, int, 0);
61 MODULE_PARM_DESC(commit_threads, "Number of commit threads");
62 
63 static struct task_struct *jfsCommitThread[MAX_COMMIT_THREADS];
64 struct task_struct *jfsIOthread;
65 struct task_struct *jfsSyncThread;
66 
67 #ifdef CONFIG_JFS_DEBUG
68 int jfsloglevel = JFS_LOGLEVEL_WARN;
69 module_param(jfsloglevel, int, 0644);
70 MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
71 #endif
72 
73 static void jfs_handle_error(struct super_block *sb)
74 {
75 	struct jfs_sb_info *sbi = JFS_SBI(sb);
76 
77 	if (sb->s_flags & MS_RDONLY)
78 		return;
79 
80 	updateSuper(sb, FM_DIRTY);
81 
82 	if (sbi->flag & JFS_ERR_PANIC)
83 		panic("JFS (device %s): panic forced after error\n",
84 			sb->s_id);
85 	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
86 		jfs_err("ERROR: (device %s): remounting filesystem "
87 			"as read-only\n",
88 			sb->s_id);
89 		sb->s_flags |= MS_RDONLY;
90 	}
91 
92 	/* nothing is done for continue beyond marking the superblock dirty */
93 }
94 
95 void jfs_error(struct super_block *sb, const char * function, ...)
96 {
97 	static char error_buf[256];
98 	va_list args;
99 
100 	va_start(args, function);
101 	vsnprintf(error_buf, sizeof(error_buf), function, args);
102 	va_end(args);
103 
104 	pr_err("ERROR: (device %s): %s\n", sb->s_id, error_buf);
105 
106 	jfs_handle_error(sb);
107 }
108 
109 static struct inode *jfs_alloc_inode(struct super_block *sb)
110 {
111 	struct jfs_inode_info *jfs_inode;
112 
113 	jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
114 	if (!jfs_inode)
115 		return NULL;
116 	return &jfs_inode->vfs_inode;
117 }
118 
119 static void jfs_i_callback(struct rcu_head *head)
120 {
121 	struct inode *inode = container_of(head, struct inode, i_rcu);
122 	struct jfs_inode_info *ji = JFS_IP(inode);
123 	kmem_cache_free(jfs_inode_cachep, ji);
124 }
125 
126 static void jfs_destroy_inode(struct inode *inode)
127 {
128 	struct jfs_inode_info *ji = JFS_IP(inode);
129 
130 	BUG_ON(!list_empty(&ji->anon_inode_list));
131 
132 	spin_lock_irq(&ji->ag_lock);
133 	if (ji->active_ag != -1) {
134 		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
135 		atomic_dec(&bmap->db_active[ji->active_ag]);
136 		ji->active_ag = -1;
137 	}
138 	spin_unlock_irq(&ji->ag_lock);
139 	call_rcu(&inode->i_rcu, jfs_i_callback);
140 }
141 
142 static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
143 {
144 	struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
145 	s64 maxinodes;
146 	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
147 
148 	jfs_info("In jfs_statfs");
149 	buf->f_type = JFS_SUPER_MAGIC;
150 	buf->f_bsize = sbi->bsize;
151 	buf->f_blocks = sbi->bmap->db_mapsize;
152 	buf->f_bfree = sbi->bmap->db_nfree;
153 	buf->f_bavail = sbi->bmap->db_nfree;
154 	/*
155 	 * If we really return the number of allocated & free inodes, some
156 	 * applications will fail because they won't see enough free inodes.
157 	 * We'll try to calculate some guess as to how many inodes we can
158 	 * really allocate
159 	 *
160 	 * buf->f_files = atomic_read(&imap->im_numinos);
161 	 * buf->f_ffree = atomic_read(&imap->im_numfree);
162 	 */
163 	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
164 			((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
165 			 << L2INOSPEREXT), (s64) 0xffffffffLL);
166 	buf->f_files = maxinodes;
167 	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
168 				    atomic_read(&imap->im_numfree));
169 	buf->f_fsid.val[0] = (u32)crc32_le(0, sbi->uuid, sizeof(sbi->uuid)/2);
170 	buf->f_fsid.val[1] = (u32)crc32_le(0, sbi->uuid + sizeof(sbi->uuid)/2,
171 					sizeof(sbi->uuid)/2);
172 
173 	buf->f_namelen = JFS_NAME_MAX;
174 	return 0;
175 }
176 
177 static void jfs_put_super(struct super_block *sb)
178 {
179 	struct jfs_sb_info *sbi = JFS_SBI(sb);
180 	int rc;
181 
182 	jfs_info("In jfs_put_super");
183 
184 	dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
185 
186 	rc = jfs_umount(sb);
187 	if (rc)
188 		jfs_err("jfs_umount failed with return code %d", rc);
189 
190 	unload_nls(sbi->nls_tab);
191 
192 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
193 	iput(sbi->direct_inode);
194 
195 	kfree(sbi);
196 }
197 
198 enum {
199 	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
200 	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
201 	Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask,
202 	Opt_discard, Opt_nodiscard, Opt_discard_minblk
203 };
204 
205 static const match_table_t tokens = {
206 	{Opt_integrity, "integrity"},
207 	{Opt_nointegrity, "nointegrity"},
208 	{Opt_iocharset, "iocharset=%s"},
209 	{Opt_resize, "resize=%u"},
210 	{Opt_resize_nosize, "resize"},
211 	{Opt_errors, "errors=%s"},
212 	{Opt_ignore, "noquota"},
213 	{Opt_ignore, "quota"},
214 	{Opt_usrquota, "usrquota"},
215 	{Opt_grpquota, "grpquota"},
216 	{Opt_uid, "uid=%u"},
217 	{Opt_gid, "gid=%u"},
218 	{Opt_umask, "umask=%u"},
219 	{Opt_discard, "discard"},
220 	{Opt_nodiscard, "nodiscard"},
221 	{Opt_discard_minblk, "discard=%u"},
222 	{Opt_err, NULL}
223 };
224 
225 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
226 			 int *flag)
227 {
228 	void *nls_map = (void *)-1;	/* -1: no change;  NULL: none */
229 	char *p;
230 	struct jfs_sb_info *sbi = JFS_SBI(sb);
231 
232 	*newLVSize = 0;
233 
234 	if (!options)
235 		return 1;
236 
237 	while ((p = strsep(&options, ",")) != NULL) {
238 		substring_t args[MAX_OPT_ARGS];
239 		int token;
240 		if (!*p)
241 			continue;
242 
243 		token = match_token(p, tokens, args);
244 		switch (token) {
245 		case Opt_integrity:
246 			*flag &= ~JFS_NOINTEGRITY;
247 			break;
248 		case Opt_nointegrity:
249 			*flag |= JFS_NOINTEGRITY;
250 			break;
251 		case Opt_ignore:
252 			/* Silently ignore the quota options */
253 			/* Don't do anything ;-) */
254 			break;
255 		case Opt_iocharset:
256 			if (nls_map && nls_map != (void *) -1)
257 				unload_nls(nls_map);
258 			if (!strcmp(args[0].from, "none"))
259 				nls_map = NULL;
260 			else {
261 				nls_map = load_nls(args[0].from);
262 				if (!nls_map) {
263 					pr_err("JFS: charset not found\n");
264 					goto cleanup;
265 				}
266 			}
267 			break;
268 		case Opt_resize:
269 		{
270 			char *resize = args[0].from;
271 			*newLVSize = simple_strtoull(resize, &resize, 0);
272 			break;
273 		}
274 		case Opt_resize_nosize:
275 		{
276 			*newLVSize = sb->s_bdev->bd_inode->i_size >>
277 				sb->s_blocksize_bits;
278 			if (*newLVSize == 0)
279 				pr_err("JFS: Cannot determine volume size\n");
280 			break;
281 		}
282 		case Opt_errors:
283 		{
284 			char *errors = args[0].from;
285 			if (!errors || !*errors)
286 				goto cleanup;
287 			if (!strcmp(errors, "continue")) {
288 				*flag &= ~JFS_ERR_REMOUNT_RO;
289 				*flag &= ~JFS_ERR_PANIC;
290 				*flag |= JFS_ERR_CONTINUE;
291 			} else if (!strcmp(errors, "remount-ro")) {
292 				*flag &= ~JFS_ERR_CONTINUE;
293 				*flag &= ~JFS_ERR_PANIC;
294 				*flag |= JFS_ERR_REMOUNT_RO;
295 			} else if (!strcmp(errors, "panic")) {
296 				*flag &= ~JFS_ERR_CONTINUE;
297 				*flag &= ~JFS_ERR_REMOUNT_RO;
298 				*flag |= JFS_ERR_PANIC;
299 			} else {
300 				pr_err("JFS: %s is an invalid error handler\n",
301 				       errors);
302 				goto cleanup;
303 			}
304 			break;
305 		}
306 
307 #ifdef CONFIG_QUOTA
308 		case Opt_quota:
309 		case Opt_usrquota:
310 			*flag |= JFS_USRQUOTA;
311 			break;
312 		case Opt_grpquota:
313 			*flag |= JFS_GRPQUOTA;
314 			break;
315 #else
316 		case Opt_usrquota:
317 		case Opt_grpquota:
318 		case Opt_quota:
319 			pr_err("JFS: quota operations not supported\n");
320 			break;
321 #endif
322 		case Opt_uid:
323 		{
324 			char *uid = args[0].from;
325 			uid_t val = simple_strtoul(uid, &uid, 0);
326 			sbi->uid = make_kuid(current_user_ns(), val);
327 			if (!uid_valid(sbi->uid))
328 				goto cleanup;
329 			break;
330 		}
331 
332 		case Opt_gid:
333 		{
334 			char *gid = args[0].from;
335 			gid_t val = simple_strtoul(gid, &gid, 0);
336 			sbi->gid = make_kgid(current_user_ns(), val);
337 			if (!gid_valid(sbi->gid))
338 				goto cleanup;
339 			break;
340 		}
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 				pr_err("JFS: Invalid value of umask\n");
348 				goto cleanup;
349 			}
350 			break;
351 		}
352 
353 		case Opt_discard:
354 		{
355 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
356 			/* if set to 1, even copying files will cause
357 			 * trimming :O
358 			 * -> user has more control over the online trimming
359 			 */
360 			sbi->minblks_trim = 64;
361 			if (blk_queue_discard(q)) {
362 				*flag |= JFS_DISCARD;
363 			} else {
364 				pr_err("JFS: discard option " \
365 					"not supported on device\n");
366 			}
367 			break;
368 		}
369 
370 		case Opt_nodiscard:
371 			*flag &= ~JFS_DISCARD;
372 			break;
373 
374 		case Opt_discard_minblk:
375 		{
376 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
377 			char *minblks_trim = args[0].from;
378 			if (blk_queue_discard(q)) {
379 				*flag |= JFS_DISCARD;
380 				sbi->minblks_trim = simple_strtoull(
381 					minblks_trim, &minblks_trim, 0);
382 			} else {
383 				pr_err("JFS: discard option " \
384 					"not supported on device\n");
385 			}
386 			break;
387 		}
388 
389 		default:
390 			printk("jfs: Unrecognized mount option \"%s\" "
391 					" or missing value\n", p);
392 			goto cleanup;
393 		}
394 	}
395 
396 	if (nls_map != (void *) -1) {
397 		/* Discard old (if remount) */
398 		unload_nls(sbi->nls_tab);
399 		sbi->nls_tab = nls_map;
400 	}
401 	return 1;
402 
403 cleanup:
404 	if (nls_map && nls_map != (void *) -1)
405 		unload_nls(nls_map);
406 	return 0;
407 }
408 
409 static int jfs_remount(struct super_block *sb, int *flags, char *data)
410 {
411 	s64 newLVSize = 0;
412 	int rc = 0;
413 	int flag = JFS_SBI(sb)->flag;
414 	int ret;
415 
416 	if (!parse_options(data, sb, &newLVSize, &flag)) {
417 		return -EINVAL;
418 	}
419 
420 	if (newLVSize) {
421 		if (sb->s_flags & MS_RDONLY) {
422 			pr_err("JFS: resize requires volume" \
423 				" to be mounted read-write\n");
424 			return -EROFS;
425 		}
426 		rc = jfs_extendfs(sb, newLVSize, 0);
427 		if (rc)
428 			return rc;
429 	}
430 
431 	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
432 		/*
433 		 * Invalidate any previously read metadata.  fsck may have
434 		 * changed the on-disk data since we mounted r/o
435 		 */
436 		truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
437 
438 		JFS_SBI(sb)->flag = flag;
439 		ret = jfs_mount_rw(sb, 1);
440 
441 		/* mark the fs r/w for quota activity */
442 		sb->s_flags &= ~MS_RDONLY;
443 
444 		dquot_resume(sb, -1);
445 		return ret;
446 	}
447 	if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
448 		rc = dquot_suspend(sb, -1);
449 		if (rc < 0) {
450 			return rc;
451 		}
452 		rc = jfs_umount_rw(sb);
453 		JFS_SBI(sb)->flag = flag;
454 		return rc;
455 	}
456 	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
457 		if (!(sb->s_flags & MS_RDONLY)) {
458 			rc = jfs_umount_rw(sb);
459 			if (rc)
460 				return rc;
461 
462 			JFS_SBI(sb)->flag = flag;
463 			ret = jfs_mount_rw(sb, 1);
464 			return ret;
465 		}
466 	JFS_SBI(sb)->flag = flag;
467 
468 	return 0;
469 }
470 
471 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
472 {
473 	struct jfs_sb_info *sbi;
474 	struct inode *inode;
475 	int rc;
476 	s64 newLVSize = 0;
477 	int flag, ret = -EINVAL;
478 
479 	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
480 
481 	if (!new_valid_dev(sb->s_bdev->bd_dev))
482 		return -EOVERFLOW;
483 
484 	sbi = kzalloc(sizeof (struct jfs_sb_info), GFP_KERNEL);
485 	if (!sbi)
486 		return -ENOMEM;
487 
488 	sb->s_fs_info = sbi;
489 	sb->s_max_links = JFS_LINK_MAX;
490 	sbi->sb = sb;
491 	sbi->uid = INVALID_UID;
492 	sbi->gid = INVALID_GID;
493 	sbi->umask = -1;
494 
495 	/* initialize the mount flag and determine the default error handler */
496 	flag = JFS_ERR_REMOUNT_RO;
497 
498 	if (!parse_options((char *) data, sb, &newLVSize, &flag))
499 		goto out_kfree;
500 	sbi->flag = flag;
501 
502 #ifdef CONFIG_JFS_POSIX_ACL
503 	sb->s_flags |= MS_POSIXACL;
504 #endif
505 
506 	if (newLVSize) {
507 		pr_err("resize option for remount only\n");
508 		goto out_kfree;
509 	}
510 
511 	/*
512 	 * Initialize blocksize to 4K.
513 	 */
514 	sb_set_blocksize(sb, PSIZE);
515 
516 	/*
517 	 * Set method vectors.
518 	 */
519 	sb->s_op = &jfs_super_operations;
520 	sb->s_export_op = &jfs_export_operations;
521 #ifdef CONFIG_QUOTA
522 	sb->dq_op = &dquot_operations;
523 	sb->s_qcop = &dquot_quotactl_ops;
524 #endif
525 
526 	/*
527 	 * Initialize direct-mapping inode/address-space
528 	 */
529 	inode = new_inode(sb);
530 	if (inode == NULL) {
531 		ret = -ENOMEM;
532 		goto out_unload;
533 	}
534 	inode->i_ino = 0;
535 	inode->i_size = sb->s_bdev->bd_inode->i_size;
536 	inode->i_mapping->a_ops = &jfs_metapage_aops;
537 	insert_inode_hash(inode);
538 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
539 
540 	sbi->direct_inode = inode;
541 
542 	rc = jfs_mount(sb);
543 	if (rc) {
544 		if (!silent) {
545 			jfs_err("jfs_mount failed w/return code = %d", rc);
546 		}
547 		goto out_mount_failed;
548 	}
549 	if (sb->s_flags & MS_RDONLY)
550 		sbi->log = NULL;
551 	else {
552 		rc = jfs_mount_rw(sb, 0);
553 		if (rc) {
554 			if (!silent) {
555 				jfs_err("jfs_mount_rw failed, return code = %d",
556 					rc);
557 			}
558 			goto out_no_rw;
559 		}
560 	}
561 
562 	sb->s_magic = JFS_SUPER_MAGIC;
563 
564 	if (sbi->mntflag & JFS_OS2)
565 		sb->s_d_op = &jfs_ci_dentry_operations;
566 
567 	inode = jfs_iget(sb, ROOT_I);
568 	if (IS_ERR(inode)) {
569 		ret = PTR_ERR(inode);
570 		goto out_no_rw;
571 	}
572 	sb->s_root = d_make_root(inode);
573 	if (!sb->s_root)
574 		goto out_no_root;
575 
576 	/* logical blocks are represented by 40 bits in pxd_t, etc. */
577 	sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
578 #if BITS_PER_LONG == 32
579 	/*
580 	 * Page cache is indexed by long.
581 	 * I would use MAX_LFS_FILESIZE, but it's only half as big
582 	 */
583 	sb->s_maxbytes = min(((u64) PAGE_CACHE_SIZE << 32) - 1, (u64)sb->s_maxbytes);
584 #endif
585 	sb->s_time_gran = 1;
586 	return 0;
587 
588 out_no_root:
589 	jfs_err("jfs_read_super: get root dentry failed");
590 
591 out_no_rw:
592 	rc = jfs_umount(sb);
593 	if (rc) {
594 		jfs_err("jfs_umount failed with return code %d", rc);
595 	}
596 out_mount_failed:
597 	filemap_write_and_wait(sbi->direct_inode->i_mapping);
598 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
599 	make_bad_inode(sbi->direct_inode);
600 	iput(sbi->direct_inode);
601 	sbi->direct_inode = NULL;
602 out_unload:
603 	if (sbi->nls_tab)
604 		unload_nls(sbi->nls_tab);
605 out_kfree:
606 	kfree(sbi);
607 	return ret;
608 }
609 
610 static int jfs_freeze(struct super_block *sb)
611 {
612 	struct jfs_sb_info *sbi = JFS_SBI(sb);
613 	struct jfs_log *log = sbi->log;
614 	int rc = 0;
615 
616 	if (!(sb->s_flags & MS_RDONLY)) {
617 		txQuiesce(sb);
618 		rc = lmLogShutdown(log);
619 		if (rc) {
620 			jfs_error(sb, "jfs_freeze: lmLogShutdown failed");
621 
622 			/* let operations fail rather than hang */
623 			txResume(sb);
624 
625 			return rc;
626 		}
627 		rc = updateSuper(sb, FM_CLEAN);
628 		if (rc) {
629 			jfs_err("jfs_freeze: updateSuper failed\n");
630 			/*
631 			 * Don't fail here. Everything succeeded except
632 			 * marking the superblock clean, so there's really
633 			 * no harm in leaving it frozen for now.
634 			 */
635 		}
636 	}
637 	return 0;
638 }
639 
640 static int jfs_unfreeze(struct super_block *sb)
641 {
642 	struct jfs_sb_info *sbi = JFS_SBI(sb);
643 	struct jfs_log *log = sbi->log;
644 	int rc = 0;
645 
646 	if (!(sb->s_flags & MS_RDONLY)) {
647 		rc = updateSuper(sb, FM_MOUNT);
648 		if (rc) {
649 			jfs_error(sb, "jfs_unfreeze: updateSuper failed");
650 			goto out;
651 		}
652 		rc = lmLogInit(log);
653 		if (rc)
654 			jfs_error(sb, "jfs_unfreeze: lmLogInit failed");
655 out:
656 		txResume(sb);
657 	}
658 	return rc;
659 }
660 
661 static struct dentry *jfs_do_mount(struct file_system_type *fs_type,
662 	int flags, const char *dev_name, void *data)
663 {
664 	return mount_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
665 }
666 
667 static int jfs_sync_fs(struct super_block *sb, int wait)
668 {
669 	struct jfs_log *log = JFS_SBI(sb)->log;
670 
671 	/* log == NULL indicates read-only mount */
672 	if (log) {
673 		/*
674 		 * Write quota structures to quota file, sync_blockdev() will
675 		 * write them to disk later
676 		 */
677 		dquot_writeback_dquots(sb, -1);
678 		jfs_flush_journal(log, wait);
679 		jfs_syncpt(log, 0);
680 	}
681 
682 	return 0;
683 }
684 
685 static int jfs_show_options(struct seq_file *seq, struct dentry *root)
686 {
687 	struct jfs_sb_info *sbi = JFS_SBI(root->d_sb);
688 
689 	if (uid_valid(sbi->uid))
690 		seq_printf(seq, ",uid=%d", from_kuid(&init_user_ns, sbi->uid));
691 	if (gid_valid(sbi->gid))
692 		seq_printf(seq, ",gid=%d", from_kgid(&init_user_ns, sbi->gid));
693 	if (sbi->umask != -1)
694 		seq_printf(seq, ",umask=%03o", sbi->umask);
695 	if (sbi->flag & JFS_NOINTEGRITY)
696 		seq_puts(seq, ",nointegrity");
697 	if (sbi->flag & JFS_DISCARD)
698 		seq_printf(seq, ",discard=%u", sbi->minblks_trim);
699 	if (sbi->nls_tab)
700 		seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
701 	if (sbi->flag & JFS_ERR_CONTINUE)
702 		seq_printf(seq, ",errors=continue");
703 	if (sbi->flag & JFS_ERR_PANIC)
704 		seq_printf(seq, ",errors=panic");
705 
706 #ifdef CONFIG_QUOTA
707 	if (sbi->flag & JFS_USRQUOTA)
708 		seq_puts(seq, ",usrquota");
709 
710 	if (sbi->flag & JFS_GRPQUOTA)
711 		seq_puts(seq, ",grpquota");
712 #endif
713 
714 	return 0;
715 }
716 
717 #ifdef CONFIG_QUOTA
718 
719 /* Read data from quotafile - avoid pagecache and such because we cannot afford
720  * acquiring the locks... As quota files are never truncated and quota code
721  * itself serializes the operations (and no one else should touch the files)
722  * we don't have to be afraid of races */
723 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
724 			      size_t len, loff_t off)
725 {
726 	struct inode *inode = sb_dqopt(sb)->files[type];
727 	sector_t blk = off >> sb->s_blocksize_bits;
728 	int err = 0;
729 	int offset = off & (sb->s_blocksize - 1);
730 	int tocopy;
731 	size_t toread;
732 	struct buffer_head tmp_bh;
733 	struct buffer_head *bh;
734 	loff_t i_size = i_size_read(inode);
735 
736 	if (off > i_size)
737 		return 0;
738 	if (off+len > i_size)
739 		len = i_size-off;
740 	toread = len;
741 	while (toread > 0) {
742 		tocopy = sb->s_blocksize - offset < toread ?
743 				sb->s_blocksize - offset : toread;
744 
745 		tmp_bh.b_state = 0;
746 		tmp_bh.b_size = 1 << inode->i_blkbits;
747 		err = jfs_get_block(inode, blk, &tmp_bh, 0);
748 		if (err)
749 			return err;
750 		if (!buffer_mapped(&tmp_bh))	/* A hole? */
751 			memset(data, 0, tocopy);
752 		else {
753 			bh = sb_bread(sb, tmp_bh.b_blocknr);
754 			if (!bh)
755 				return -EIO;
756 			memcpy(data, bh->b_data+offset, tocopy);
757 			brelse(bh);
758 		}
759 		offset = 0;
760 		toread -= tocopy;
761 		data += tocopy;
762 		blk++;
763 	}
764 	return len;
765 }
766 
767 /* Write to quotafile */
768 static ssize_t jfs_quota_write(struct super_block *sb, int type,
769 			       const char *data, size_t len, loff_t off)
770 {
771 	struct inode *inode = sb_dqopt(sb)->files[type];
772 	sector_t blk = off >> sb->s_blocksize_bits;
773 	int err = 0;
774 	int offset = off & (sb->s_blocksize - 1);
775 	int tocopy;
776 	size_t towrite = len;
777 	struct buffer_head tmp_bh;
778 	struct buffer_head *bh;
779 
780 	mutex_lock(&inode->i_mutex);
781 	while (towrite > 0) {
782 		tocopy = sb->s_blocksize - offset < towrite ?
783 				sb->s_blocksize - offset : towrite;
784 
785 		tmp_bh.b_state = 0;
786 		tmp_bh.b_size = 1 << inode->i_blkbits;
787 		err = jfs_get_block(inode, blk, &tmp_bh, 1);
788 		if (err)
789 			goto out;
790 		if (offset || tocopy != sb->s_blocksize)
791 			bh = sb_bread(sb, tmp_bh.b_blocknr);
792 		else
793 			bh = sb_getblk(sb, tmp_bh.b_blocknr);
794 		if (!bh) {
795 			err = -EIO;
796 			goto out;
797 		}
798 		lock_buffer(bh);
799 		memcpy(bh->b_data+offset, data, tocopy);
800 		flush_dcache_page(bh->b_page);
801 		set_buffer_uptodate(bh);
802 		mark_buffer_dirty(bh);
803 		unlock_buffer(bh);
804 		brelse(bh);
805 		offset = 0;
806 		towrite -= tocopy;
807 		data += tocopy;
808 		blk++;
809 	}
810 out:
811 	if (len == towrite) {
812 		mutex_unlock(&inode->i_mutex);
813 		return err;
814 	}
815 	if (inode->i_size < off+len-towrite)
816 		i_size_write(inode, off+len-towrite);
817 	inode->i_version++;
818 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
819 	mark_inode_dirty(inode);
820 	mutex_unlock(&inode->i_mutex);
821 	return len - towrite;
822 }
823 
824 #endif
825 
826 static const struct super_operations jfs_super_operations = {
827 	.alloc_inode	= jfs_alloc_inode,
828 	.destroy_inode	= jfs_destroy_inode,
829 	.dirty_inode	= jfs_dirty_inode,
830 	.write_inode	= jfs_write_inode,
831 	.evict_inode	= jfs_evict_inode,
832 	.put_super	= jfs_put_super,
833 	.sync_fs	= jfs_sync_fs,
834 	.freeze_fs	= jfs_freeze,
835 	.unfreeze_fs	= jfs_unfreeze,
836 	.statfs		= jfs_statfs,
837 	.remount_fs	= jfs_remount,
838 	.show_options	= jfs_show_options,
839 #ifdef CONFIG_QUOTA
840 	.quota_read	= jfs_quota_read,
841 	.quota_write	= jfs_quota_write,
842 #endif
843 };
844 
845 static const struct export_operations jfs_export_operations = {
846 	.fh_to_dentry	= jfs_fh_to_dentry,
847 	.fh_to_parent	= jfs_fh_to_parent,
848 	.get_parent	= jfs_get_parent,
849 };
850 
851 static struct file_system_type jfs_fs_type = {
852 	.owner		= THIS_MODULE,
853 	.name		= "jfs",
854 	.mount		= jfs_do_mount,
855 	.kill_sb	= kill_block_super,
856 	.fs_flags	= FS_REQUIRES_DEV,
857 };
858 MODULE_ALIAS_FS("jfs");
859 
860 static void init_once(void *foo)
861 {
862 	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
863 
864 	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
865 	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
866 	init_rwsem(&jfs_ip->rdwrlock);
867 	mutex_init(&jfs_ip->commit_mutex);
868 	init_rwsem(&jfs_ip->xattr_sem);
869 	spin_lock_init(&jfs_ip->ag_lock);
870 	jfs_ip->active_ag = -1;
871 	inode_init_once(&jfs_ip->vfs_inode);
872 }
873 
874 static int __init init_jfs_fs(void)
875 {
876 	int i;
877 	int rc;
878 
879 	jfs_inode_cachep =
880 	    kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
881 			    SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
882 			    init_once);
883 	if (jfs_inode_cachep == NULL)
884 		return -ENOMEM;
885 
886 	/*
887 	 * Metapage initialization
888 	 */
889 	rc = metapage_init();
890 	if (rc) {
891 		jfs_err("metapage_init failed w/rc = %d", rc);
892 		goto free_slab;
893 	}
894 
895 	/*
896 	 * Transaction Manager initialization
897 	 */
898 	rc = txInit();
899 	if (rc) {
900 		jfs_err("txInit failed w/rc = %d", rc);
901 		goto free_metapage;
902 	}
903 
904 	/*
905 	 * I/O completion thread (endio)
906 	 */
907 	jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
908 	if (IS_ERR(jfsIOthread)) {
909 		rc = PTR_ERR(jfsIOthread);
910 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
911 		goto end_txmngr;
912 	}
913 
914 	if (commit_threads < 1)
915 		commit_threads = num_online_cpus();
916 	if (commit_threads > MAX_COMMIT_THREADS)
917 		commit_threads = MAX_COMMIT_THREADS;
918 
919 	for (i = 0; i < commit_threads; i++) {
920 		jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL, "jfsCommit");
921 		if (IS_ERR(jfsCommitThread[i])) {
922 			rc = PTR_ERR(jfsCommitThread[i]);
923 			jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
924 			commit_threads = i;
925 			goto kill_committask;
926 		}
927 	}
928 
929 	jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
930 	if (IS_ERR(jfsSyncThread)) {
931 		rc = PTR_ERR(jfsSyncThread);
932 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
933 		goto kill_committask;
934 	}
935 
936 #ifdef PROC_FS_JFS
937 	jfs_proc_init();
938 #endif
939 
940 	rc = register_filesystem(&jfs_fs_type);
941 	if (!rc)
942 		return 0;
943 
944 #ifdef PROC_FS_JFS
945 	jfs_proc_clean();
946 #endif
947 	kthread_stop(jfsSyncThread);
948 kill_committask:
949 	for (i = 0; i < commit_threads; i++)
950 		kthread_stop(jfsCommitThread[i]);
951 	kthread_stop(jfsIOthread);
952 end_txmngr:
953 	txExit();
954 free_metapage:
955 	metapage_exit();
956 free_slab:
957 	kmem_cache_destroy(jfs_inode_cachep);
958 	return rc;
959 }
960 
961 static void __exit exit_jfs_fs(void)
962 {
963 	int i;
964 
965 	jfs_info("exit_jfs_fs called");
966 
967 	txExit();
968 	metapage_exit();
969 
970 	kthread_stop(jfsIOthread);
971 	for (i = 0; i < commit_threads; i++)
972 		kthread_stop(jfsCommitThread[i]);
973 	kthread_stop(jfsSyncThread);
974 #ifdef PROC_FS_JFS
975 	jfs_proc_clean();
976 #endif
977 	unregister_filesystem(&jfs_fs_type);
978 
979 	/*
980 	 * Make sure all delayed rcu free inodes are flushed before we
981 	 * destroy cache.
982 	 */
983 	rcu_barrier();
984 	kmem_cache_destroy(jfs_inode_cachep);
985 }
986 
987 module_init(init_jfs_fs)
988 module_exit(exit_jfs_fs)
989