xref: /openbmc/linux/fs/jfs/super.c (revision 32981ea5)
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 #include "jfs_xattr.h"
48 
49 MODULE_DESCRIPTION("The Journaled Filesystem (JFS)");
50 MODULE_AUTHOR("Steve Best/Dave Kleikamp/Barry Arndt, IBM");
51 MODULE_LICENSE("GPL");
52 
53 static struct kmem_cache *jfs_inode_cachep;
54 
55 static const struct super_operations jfs_super_operations;
56 static const struct export_operations jfs_export_operations;
57 static struct file_system_type jfs_fs_type;
58 
59 #define MAX_COMMIT_THREADS 64
60 static int commit_threads;
61 module_param(commit_threads, int, 0);
62 MODULE_PARM_DESC(commit_threads, "Number of commit threads");
63 
64 static struct task_struct *jfsCommitThread[MAX_COMMIT_THREADS];
65 struct task_struct *jfsIOthread;
66 struct task_struct *jfsSyncThread;
67 
68 #ifdef CONFIG_JFS_DEBUG
69 int jfsloglevel = JFS_LOGLEVEL_WARN;
70 module_param(jfsloglevel, int, 0644);
71 MODULE_PARM_DESC(jfsloglevel, "Specify JFS loglevel (0, 1 or 2)");
72 #endif
73 
74 static void jfs_handle_error(struct super_block *sb)
75 {
76 	struct jfs_sb_info *sbi = JFS_SBI(sb);
77 
78 	if (sb->s_flags & MS_RDONLY)
79 		return;
80 
81 	updateSuper(sb, FM_DIRTY);
82 
83 	if (sbi->flag & JFS_ERR_PANIC)
84 		panic("JFS (device %s): panic forced after error\n",
85 			sb->s_id);
86 	else if (sbi->flag & JFS_ERR_REMOUNT_RO) {
87 		jfs_err("ERROR: (device %s): remounting filesystem as read-only",
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 *fmt, ...)
96 {
97 	struct va_format vaf;
98 	va_list args;
99 
100 	va_start(args, fmt);
101 
102 	vaf.fmt = fmt;
103 	vaf.va = &args;
104 
105 	pr_err("ERROR: (device %s): %ps: %pV\n",
106 	       sb->s_id, __builtin_return_address(0), &vaf);
107 
108 	va_end(args);
109 
110 	jfs_handle_error(sb);
111 }
112 
113 static struct inode *jfs_alloc_inode(struct super_block *sb)
114 {
115 	struct jfs_inode_info *jfs_inode;
116 
117 	jfs_inode = kmem_cache_alloc(jfs_inode_cachep, GFP_NOFS);
118 	if (!jfs_inode)
119 		return NULL;
120 #ifdef CONFIG_QUOTA
121 	memset(&jfs_inode->i_dquot, 0, sizeof(jfs_inode->i_dquot));
122 #endif
123 	return &jfs_inode->vfs_inode;
124 }
125 
126 static void jfs_i_callback(struct rcu_head *head)
127 {
128 	struct inode *inode = container_of(head, struct inode, i_rcu);
129 	struct jfs_inode_info *ji = JFS_IP(inode);
130 	kmem_cache_free(jfs_inode_cachep, ji);
131 }
132 
133 static void jfs_destroy_inode(struct inode *inode)
134 {
135 	struct jfs_inode_info *ji = JFS_IP(inode);
136 
137 	BUG_ON(!list_empty(&ji->anon_inode_list));
138 
139 	spin_lock_irq(&ji->ag_lock);
140 	if (ji->active_ag != -1) {
141 		struct bmap *bmap = JFS_SBI(inode->i_sb)->bmap;
142 		atomic_dec(&bmap->db_active[ji->active_ag]);
143 		ji->active_ag = -1;
144 	}
145 	spin_unlock_irq(&ji->ag_lock);
146 	call_rcu(&inode->i_rcu, jfs_i_callback);
147 }
148 
149 static int jfs_statfs(struct dentry *dentry, struct kstatfs *buf)
150 {
151 	struct jfs_sb_info *sbi = JFS_SBI(dentry->d_sb);
152 	s64 maxinodes;
153 	struct inomap *imap = JFS_IP(sbi->ipimap)->i_imap;
154 
155 	jfs_info("In jfs_statfs");
156 	buf->f_type = JFS_SUPER_MAGIC;
157 	buf->f_bsize = sbi->bsize;
158 	buf->f_blocks = sbi->bmap->db_mapsize;
159 	buf->f_bfree = sbi->bmap->db_nfree;
160 	buf->f_bavail = sbi->bmap->db_nfree;
161 	/*
162 	 * If we really return the number of allocated & free inodes, some
163 	 * applications will fail because they won't see enough free inodes.
164 	 * We'll try to calculate some guess as to how many inodes we can
165 	 * really allocate
166 	 *
167 	 * buf->f_files = atomic_read(&imap->im_numinos);
168 	 * buf->f_ffree = atomic_read(&imap->im_numfree);
169 	 */
170 	maxinodes = min((s64) atomic_read(&imap->im_numinos) +
171 			((sbi->bmap->db_nfree >> imap->im_l2nbperiext)
172 			 << L2INOSPEREXT), (s64) 0xffffffffLL);
173 	buf->f_files = maxinodes;
174 	buf->f_ffree = maxinodes - (atomic_read(&imap->im_numinos) -
175 				    atomic_read(&imap->im_numfree));
176 	buf->f_fsid.val[0] = (u32)crc32_le(0, sbi->uuid, sizeof(sbi->uuid)/2);
177 	buf->f_fsid.val[1] = (u32)crc32_le(0, sbi->uuid + sizeof(sbi->uuid)/2,
178 					sizeof(sbi->uuid)/2);
179 
180 	buf->f_namelen = JFS_NAME_MAX;
181 	return 0;
182 }
183 
184 static void jfs_put_super(struct super_block *sb)
185 {
186 	struct jfs_sb_info *sbi = JFS_SBI(sb);
187 	int rc;
188 
189 	jfs_info("In jfs_put_super");
190 
191 	dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
192 
193 	rc = jfs_umount(sb);
194 	if (rc)
195 		jfs_err("jfs_umount failed with return code %d", rc);
196 
197 	unload_nls(sbi->nls_tab);
198 
199 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
200 	iput(sbi->direct_inode);
201 
202 	kfree(sbi);
203 }
204 
205 enum {
206 	Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize,
207 	Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota,
208 	Opt_usrquota, Opt_grpquota, Opt_uid, Opt_gid, Opt_umask,
209 	Opt_discard, Opt_nodiscard, Opt_discard_minblk
210 };
211 
212 static const match_table_t tokens = {
213 	{Opt_integrity, "integrity"},
214 	{Opt_nointegrity, "nointegrity"},
215 	{Opt_iocharset, "iocharset=%s"},
216 	{Opt_resize, "resize=%u"},
217 	{Opt_resize_nosize, "resize"},
218 	{Opt_errors, "errors=%s"},
219 	{Opt_ignore, "noquota"},
220 	{Opt_ignore, "quota"},
221 	{Opt_usrquota, "usrquota"},
222 	{Opt_grpquota, "grpquota"},
223 	{Opt_uid, "uid=%u"},
224 	{Opt_gid, "gid=%u"},
225 	{Opt_umask, "umask=%u"},
226 	{Opt_discard, "discard"},
227 	{Opt_nodiscard, "nodiscard"},
228 	{Opt_discard_minblk, "discard=%u"},
229 	{Opt_err, NULL}
230 };
231 
232 static int parse_options(char *options, struct super_block *sb, s64 *newLVSize,
233 			 int *flag)
234 {
235 	void *nls_map = (void *)-1;	/* -1: no change;  NULL: none */
236 	char *p;
237 	struct jfs_sb_info *sbi = JFS_SBI(sb);
238 
239 	*newLVSize = 0;
240 
241 	if (!options)
242 		return 1;
243 
244 	while ((p = strsep(&options, ",")) != NULL) {
245 		substring_t args[MAX_OPT_ARGS];
246 		int token;
247 		if (!*p)
248 			continue;
249 
250 		token = match_token(p, tokens, args);
251 		switch (token) {
252 		case Opt_integrity:
253 			*flag &= ~JFS_NOINTEGRITY;
254 			break;
255 		case Opt_nointegrity:
256 			*flag |= JFS_NOINTEGRITY;
257 			break;
258 		case Opt_ignore:
259 			/* Silently ignore the quota options */
260 			/* Don't do anything ;-) */
261 			break;
262 		case Opt_iocharset:
263 			if (nls_map && nls_map != (void *) -1)
264 				unload_nls(nls_map);
265 			if (!strcmp(args[0].from, "none"))
266 				nls_map = NULL;
267 			else {
268 				nls_map = load_nls(args[0].from);
269 				if (!nls_map) {
270 					pr_err("JFS: charset not found\n");
271 					goto cleanup;
272 				}
273 			}
274 			break;
275 		case Opt_resize:
276 		{
277 			char *resize = args[0].from;
278 			int rc = kstrtoll(resize, 0, newLVSize);
279 
280 			if (rc)
281 				goto cleanup;
282 			break;
283 		}
284 		case Opt_resize_nosize:
285 		{
286 			*newLVSize = sb->s_bdev->bd_inode->i_size >>
287 				sb->s_blocksize_bits;
288 			if (*newLVSize == 0)
289 				pr_err("JFS: Cannot determine volume size\n");
290 			break;
291 		}
292 		case Opt_errors:
293 		{
294 			char *errors = args[0].from;
295 			if (!errors || !*errors)
296 				goto cleanup;
297 			if (!strcmp(errors, "continue")) {
298 				*flag &= ~JFS_ERR_REMOUNT_RO;
299 				*flag &= ~JFS_ERR_PANIC;
300 				*flag |= JFS_ERR_CONTINUE;
301 			} else if (!strcmp(errors, "remount-ro")) {
302 				*flag &= ~JFS_ERR_CONTINUE;
303 				*flag &= ~JFS_ERR_PANIC;
304 				*flag |= JFS_ERR_REMOUNT_RO;
305 			} else if (!strcmp(errors, "panic")) {
306 				*flag &= ~JFS_ERR_CONTINUE;
307 				*flag &= ~JFS_ERR_REMOUNT_RO;
308 				*flag |= JFS_ERR_PANIC;
309 			} else {
310 				pr_err("JFS: %s is an invalid error handler\n",
311 				       errors);
312 				goto cleanup;
313 			}
314 			break;
315 		}
316 
317 #ifdef CONFIG_QUOTA
318 		case Opt_quota:
319 		case Opt_usrquota:
320 			*flag |= JFS_USRQUOTA;
321 			break;
322 		case Opt_grpquota:
323 			*flag |= JFS_GRPQUOTA;
324 			break;
325 #else
326 		case Opt_usrquota:
327 		case Opt_grpquota:
328 		case Opt_quota:
329 			pr_err("JFS: quota operations not supported\n");
330 			break;
331 #endif
332 		case Opt_uid:
333 		{
334 			char *uid = args[0].from;
335 			uid_t val;
336 			int rc = kstrtouint(uid, 0, &val);
337 
338 			if (rc)
339 				goto cleanup;
340 			sbi->uid = make_kuid(current_user_ns(), val);
341 			if (!uid_valid(sbi->uid))
342 				goto cleanup;
343 			break;
344 		}
345 
346 		case Opt_gid:
347 		{
348 			char *gid = args[0].from;
349 			gid_t val;
350 			int rc = kstrtouint(gid, 0, &val);
351 
352 			if (rc)
353 				goto cleanup;
354 			sbi->gid = make_kgid(current_user_ns(), val);
355 			if (!gid_valid(sbi->gid))
356 				goto cleanup;
357 			break;
358 		}
359 
360 		case Opt_umask:
361 		{
362 			char *umask = args[0].from;
363 			int rc = kstrtouint(umask, 8, &sbi->umask);
364 
365 			if (rc)
366 				goto cleanup;
367 			if (sbi->umask & ~0777) {
368 				pr_err("JFS: Invalid value of umask\n");
369 				goto cleanup;
370 			}
371 			break;
372 		}
373 
374 		case Opt_discard:
375 		{
376 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
377 			/* if set to 1, even copying files will cause
378 			 * trimming :O
379 			 * -> user has more control over the online trimming
380 			 */
381 			sbi->minblks_trim = 64;
382 			if (blk_queue_discard(q))
383 				*flag |= JFS_DISCARD;
384 			else
385 				pr_err("JFS: discard option not supported on device\n");
386 			break;
387 		}
388 
389 		case Opt_nodiscard:
390 			*flag &= ~JFS_DISCARD;
391 			break;
392 
393 		case Opt_discard_minblk:
394 		{
395 			struct request_queue *q = bdev_get_queue(sb->s_bdev);
396 			char *minblks_trim = args[0].from;
397 			int rc;
398 			if (blk_queue_discard(q)) {
399 				*flag |= JFS_DISCARD;
400 				rc = kstrtouint(minblks_trim, 0,
401 						&sbi->minblks_trim);
402 				if (rc)
403 					goto cleanup;
404 			} else
405 				pr_err("JFS: discard option not supported on device\n");
406 			break;
407 		}
408 
409 		default:
410 			printk("jfs: Unrecognized mount option \"%s\" or missing value\n",
411 			       p);
412 			goto cleanup;
413 		}
414 	}
415 
416 	if (nls_map != (void *) -1) {
417 		/* Discard old (if remount) */
418 		unload_nls(sbi->nls_tab);
419 		sbi->nls_tab = nls_map;
420 	}
421 	return 1;
422 
423 cleanup:
424 	if (nls_map && nls_map != (void *) -1)
425 		unload_nls(nls_map);
426 	return 0;
427 }
428 
429 static int jfs_remount(struct super_block *sb, int *flags, char *data)
430 {
431 	s64 newLVSize = 0;
432 	int rc = 0;
433 	int flag = JFS_SBI(sb)->flag;
434 	int ret;
435 
436 	sync_filesystem(sb);
437 	if (!parse_options(data, sb, &newLVSize, &flag))
438 		return -EINVAL;
439 
440 	if (newLVSize) {
441 		if (sb->s_flags & MS_RDONLY) {
442 			pr_err("JFS: resize requires volume to be mounted read-write\n");
443 			return -EROFS;
444 		}
445 		rc = jfs_extendfs(sb, newLVSize, 0);
446 		if (rc)
447 			return rc;
448 	}
449 
450 	if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
451 		/*
452 		 * Invalidate any previously read metadata.  fsck may have
453 		 * changed the on-disk data since we mounted r/o
454 		 */
455 		truncate_inode_pages(JFS_SBI(sb)->direct_inode->i_mapping, 0);
456 
457 		JFS_SBI(sb)->flag = flag;
458 		ret = jfs_mount_rw(sb, 1);
459 
460 		/* mark the fs r/w for quota activity */
461 		sb->s_flags &= ~MS_RDONLY;
462 
463 		dquot_resume(sb, -1);
464 		return ret;
465 	}
466 	if ((!(sb->s_flags & MS_RDONLY)) && (*flags & MS_RDONLY)) {
467 		rc = dquot_suspend(sb, -1);
468 		if (rc < 0)
469 			return rc;
470 		rc = jfs_umount_rw(sb);
471 		JFS_SBI(sb)->flag = flag;
472 		return rc;
473 	}
474 	if ((JFS_SBI(sb)->flag & JFS_NOINTEGRITY) != (flag & JFS_NOINTEGRITY))
475 		if (!(sb->s_flags & MS_RDONLY)) {
476 			rc = jfs_umount_rw(sb);
477 			if (rc)
478 				return rc;
479 
480 			JFS_SBI(sb)->flag = flag;
481 			ret = jfs_mount_rw(sb, 1);
482 			return ret;
483 		}
484 	JFS_SBI(sb)->flag = flag;
485 
486 	return 0;
487 }
488 
489 static int jfs_fill_super(struct super_block *sb, void *data, int silent)
490 {
491 	struct jfs_sb_info *sbi;
492 	struct inode *inode;
493 	int rc;
494 	s64 newLVSize = 0;
495 	int flag, ret = -EINVAL;
496 
497 	jfs_info("In jfs_read_super: s_flags=0x%lx", sb->s_flags);
498 
499 	sbi = kzalloc(sizeof(struct jfs_sb_info), GFP_KERNEL);
500 	if (!sbi)
501 		return -ENOMEM;
502 
503 	sb->s_fs_info = sbi;
504 	sb->s_max_links = JFS_LINK_MAX;
505 	sbi->sb = sb;
506 	sbi->uid = INVALID_UID;
507 	sbi->gid = INVALID_GID;
508 	sbi->umask = -1;
509 
510 	/* initialize the mount flag and determine the default error handler */
511 	flag = JFS_ERR_REMOUNT_RO;
512 
513 	if (!parse_options((char *) data, sb, &newLVSize, &flag))
514 		goto out_kfree;
515 	sbi->flag = flag;
516 
517 #ifdef CONFIG_JFS_POSIX_ACL
518 	sb->s_flags |= MS_POSIXACL;
519 #endif
520 
521 	if (newLVSize) {
522 		pr_err("resize option for remount only\n");
523 		goto out_kfree;
524 	}
525 
526 	/*
527 	 * Initialize blocksize to 4K.
528 	 */
529 	sb_set_blocksize(sb, PSIZE);
530 
531 	/*
532 	 * Set method vectors.
533 	 */
534 	sb->s_op = &jfs_super_operations;
535 	sb->s_export_op = &jfs_export_operations;
536 	sb->s_xattr = jfs_xattr_handlers;
537 #ifdef CONFIG_QUOTA
538 	sb->dq_op = &dquot_operations;
539 	sb->s_qcop = &dquot_quotactl_ops;
540 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
541 #endif
542 
543 	/*
544 	 * Initialize direct-mapping inode/address-space
545 	 */
546 	inode = new_inode(sb);
547 	if (inode == NULL) {
548 		ret = -ENOMEM;
549 		goto out_unload;
550 	}
551 	inode->i_ino = 0;
552 	inode->i_size = sb->s_bdev->bd_inode->i_size;
553 	inode->i_mapping->a_ops = &jfs_metapage_aops;
554 	hlist_add_fake(&inode->i_hash);
555 	mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
556 
557 	sbi->direct_inode = inode;
558 
559 	rc = jfs_mount(sb);
560 	if (rc) {
561 		if (!silent)
562 			jfs_err("jfs_mount failed w/return code = %d", rc);
563 		goto out_mount_failed;
564 	}
565 	if (sb->s_flags & MS_RDONLY)
566 		sbi->log = NULL;
567 	else {
568 		rc = jfs_mount_rw(sb, 0);
569 		if (rc) {
570 			if (!silent) {
571 				jfs_err("jfs_mount_rw failed, return code = %d",
572 					rc);
573 			}
574 			goto out_no_rw;
575 		}
576 	}
577 
578 	sb->s_magic = JFS_SUPER_MAGIC;
579 
580 	if (sbi->mntflag & JFS_OS2)
581 		sb->s_d_op = &jfs_ci_dentry_operations;
582 
583 	inode = jfs_iget(sb, ROOT_I);
584 	if (IS_ERR(inode)) {
585 		ret = PTR_ERR(inode);
586 		goto out_no_rw;
587 	}
588 	sb->s_root = d_make_root(inode);
589 	if (!sb->s_root)
590 		goto out_no_root;
591 
592 	/* logical blocks are represented by 40 bits in pxd_t, etc. */
593 	sb->s_maxbytes = ((u64) sb->s_blocksize) << 40;
594 #if BITS_PER_LONG == 32
595 	/*
596 	 * Page cache is indexed by long.
597 	 * I would use MAX_LFS_FILESIZE, but it's only half as big
598 	 */
599 	sb->s_maxbytes = min(((u64) PAGE_SIZE << 32) - 1,
600 			     (u64)sb->s_maxbytes);
601 #endif
602 	sb->s_time_gran = 1;
603 	return 0;
604 
605 out_no_root:
606 	jfs_err("jfs_read_super: get root dentry failed");
607 
608 out_no_rw:
609 	rc = jfs_umount(sb);
610 	if (rc)
611 		jfs_err("jfs_umount failed with return code %d", rc);
612 out_mount_failed:
613 	filemap_write_and_wait(sbi->direct_inode->i_mapping);
614 	truncate_inode_pages(sbi->direct_inode->i_mapping, 0);
615 	make_bad_inode(sbi->direct_inode);
616 	iput(sbi->direct_inode);
617 	sbi->direct_inode = NULL;
618 out_unload:
619 	unload_nls(sbi->nls_tab);
620 out_kfree:
621 	kfree(sbi);
622 	return ret;
623 }
624 
625 static int jfs_freeze(struct super_block *sb)
626 {
627 	struct jfs_sb_info *sbi = JFS_SBI(sb);
628 	struct jfs_log *log = sbi->log;
629 	int rc = 0;
630 
631 	if (!(sb->s_flags & MS_RDONLY)) {
632 		txQuiesce(sb);
633 		rc = lmLogShutdown(log);
634 		if (rc) {
635 			jfs_error(sb, "lmLogShutdown failed\n");
636 
637 			/* let operations fail rather than hang */
638 			txResume(sb);
639 
640 			return rc;
641 		}
642 		rc = updateSuper(sb, FM_CLEAN);
643 		if (rc) {
644 			jfs_err("jfs_freeze: updateSuper failed");
645 			/*
646 			 * Don't fail here. Everything succeeded except
647 			 * marking the superblock clean, so there's really
648 			 * no harm in leaving it frozen for now.
649 			 */
650 		}
651 	}
652 	return 0;
653 }
654 
655 static int jfs_unfreeze(struct super_block *sb)
656 {
657 	struct jfs_sb_info *sbi = JFS_SBI(sb);
658 	struct jfs_log *log = sbi->log;
659 	int rc = 0;
660 
661 	if (!(sb->s_flags & MS_RDONLY)) {
662 		rc = updateSuper(sb, FM_MOUNT);
663 		if (rc) {
664 			jfs_error(sb, "updateSuper failed\n");
665 			goto out;
666 		}
667 		rc = lmLogInit(log);
668 		if (rc)
669 			jfs_error(sb, "lmLogInit failed\n");
670 out:
671 		txResume(sb);
672 	}
673 	return rc;
674 }
675 
676 static struct dentry *jfs_do_mount(struct file_system_type *fs_type,
677 	int flags, const char *dev_name, void *data)
678 {
679 	return mount_bdev(fs_type, flags, dev_name, data, jfs_fill_super);
680 }
681 
682 static int jfs_sync_fs(struct super_block *sb, int wait)
683 {
684 	struct jfs_log *log = JFS_SBI(sb)->log;
685 
686 	/* log == NULL indicates read-only mount */
687 	if (log) {
688 		/*
689 		 * Write quota structures to quota file, sync_blockdev() will
690 		 * write them to disk later
691 		 */
692 		dquot_writeback_dquots(sb, -1);
693 		jfs_flush_journal(log, wait);
694 		jfs_syncpt(log, 0);
695 	}
696 
697 	return 0;
698 }
699 
700 static int jfs_show_options(struct seq_file *seq, struct dentry *root)
701 {
702 	struct jfs_sb_info *sbi = JFS_SBI(root->d_sb);
703 
704 	if (uid_valid(sbi->uid))
705 		seq_printf(seq, ",uid=%d", from_kuid(&init_user_ns, sbi->uid));
706 	if (gid_valid(sbi->gid))
707 		seq_printf(seq, ",gid=%d", from_kgid(&init_user_ns, sbi->gid));
708 	if (sbi->umask != -1)
709 		seq_printf(seq, ",umask=%03o", sbi->umask);
710 	if (sbi->flag & JFS_NOINTEGRITY)
711 		seq_puts(seq, ",nointegrity");
712 	if (sbi->flag & JFS_DISCARD)
713 		seq_printf(seq, ",discard=%u", sbi->minblks_trim);
714 	if (sbi->nls_tab)
715 		seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset);
716 	if (sbi->flag & JFS_ERR_CONTINUE)
717 		seq_printf(seq, ",errors=continue");
718 	if (sbi->flag & JFS_ERR_PANIC)
719 		seq_printf(seq, ",errors=panic");
720 
721 #ifdef CONFIG_QUOTA
722 	if (sbi->flag & JFS_USRQUOTA)
723 		seq_puts(seq, ",usrquota");
724 
725 	if (sbi->flag & JFS_GRPQUOTA)
726 		seq_puts(seq, ",grpquota");
727 #endif
728 
729 	return 0;
730 }
731 
732 #ifdef CONFIG_QUOTA
733 
734 /* Read data from quotafile - avoid pagecache and such because we cannot afford
735  * acquiring the locks... As quota files are never truncated and quota code
736  * itself serializes the operations (and no one else should touch the files)
737  * we don't have to be afraid of races */
738 static ssize_t jfs_quota_read(struct super_block *sb, int type, char *data,
739 			      size_t len, loff_t off)
740 {
741 	struct inode *inode = sb_dqopt(sb)->files[type];
742 	sector_t blk = off >> sb->s_blocksize_bits;
743 	int err = 0;
744 	int offset = off & (sb->s_blocksize - 1);
745 	int tocopy;
746 	size_t toread;
747 	struct buffer_head tmp_bh;
748 	struct buffer_head *bh;
749 	loff_t i_size = i_size_read(inode);
750 
751 	if (off > i_size)
752 		return 0;
753 	if (off+len > i_size)
754 		len = i_size-off;
755 	toread = len;
756 	while (toread > 0) {
757 		tocopy = sb->s_blocksize - offset < toread ?
758 				sb->s_blocksize - offset : toread;
759 
760 		tmp_bh.b_state = 0;
761 		tmp_bh.b_size = 1 << inode->i_blkbits;
762 		err = jfs_get_block(inode, blk, &tmp_bh, 0);
763 		if (err)
764 			return err;
765 		if (!buffer_mapped(&tmp_bh))	/* A hole? */
766 			memset(data, 0, tocopy);
767 		else {
768 			bh = sb_bread(sb, tmp_bh.b_blocknr);
769 			if (!bh)
770 				return -EIO;
771 			memcpy(data, bh->b_data+offset, tocopy);
772 			brelse(bh);
773 		}
774 		offset = 0;
775 		toread -= tocopy;
776 		data += tocopy;
777 		blk++;
778 	}
779 	return len;
780 }
781 
782 /* Write to quotafile */
783 static ssize_t jfs_quota_write(struct super_block *sb, int type,
784 			       const char *data, size_t len, loff_t off)
785 {
786 	struct inode *inode = sb_dqopt(sb)->files[type];
787 	sector_t blk = off >> sb->s_blocksize_bits;
788 	int err = 0;
789 	int offset = off & (sb->s_blocksize - 1);
790 	int tocopy;
791 	size_t towrite = len;
792 	struct buffer_head tmp_bh;
793 	struct buffer_head *bh;
794 
795 	inode_lock(inode);
796 	while (towrite > 0) {
797 		tocopy = sb->s_blocksize - offset < towrite ?
798 				sb->s_blocksize - offset : towrite;
799 
800 		tmp_bh.b_state = 0;
801 		tmp_bh.b_size = 1 << inode->i_blkbits;
802 		err = jfs_get_block(inode, blk, &tmp_bh, 1);
803 		if (err)
804 			goto out;
805 		if (offset || tocopy != sb->s_blocksize)
806 			bh = sb_bread(sb, tmp_bh.b_blocknr);
807 		else
808 			bh = sb_getblk(sb, tmp_bh.b_blocknr);
809 		if (!bh) {
810 			err = -EIO;
811 			goto out;
812 		}
813 		lock_buffer(bh);
814 		memcpy(bh->b_data+offset, data, tocopy);
815 		flush_dcache_page(bh->b_page);
816 		set_buffer_uptodate(bh);
817 		mark_buffer_dirty(bh);
818 		unlock_buffer(bh);
819 		brelse(bh);
820 		offset = 0;
821 		towrite -= tocopy;
822 		data += tocopy;
823 		blk++;
824 	}
825 out:
826 	if (len == towrite) {
827 		inode_unlock(inode);
828 		return err;
829 	}
830 	if (inode->i_size < off+len-towrite)
831 		i_size_write(inode, off+len-towrite);
832 	inode->i_version++;
833 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
834 	mark_inode_dirty(inode);
835 	inode_unlock(inode);
836 	return len - towrite;
837 }
838 
839 static struct dquot **jfs_get_dquots(struct inode *inode)
840 {
841 	return JFS_IP(inode)->i_dquot;
842 }
843 #endif
844 
845 static const struct super_operations jfs_super_operations = {
846 	.alloc_inode	= jfs_alloc_inode,
847 	.destroy_inode	= jfs_destroy_inode,
848 	.dirty_inode	= jfs_dirty_inode,
849 	.write_inode	= jfs_write_inode,
850 	.evict_inode	= jfs_evict_inode,
851 	.put_super	= jfs_put_super,
852 	.sync_fs	= jfs_sync_fs,
853 	.freeze_fs	= jfs_freeze,
854 	.unfreeze_fs	= jfs_unfreeze,
855 	.statfs		= jfs_statfs,
856 	.remount_fs	= jfs_remount,
857 	.show_options	= jfs_show_options,
858 #ifdef CONFIG_QUOTA
859 	.quota_read	= jfs_quota_read,
860 	.quota_write	= jfs_quota_write,
861 	.get_dquots	= jfs_get_dquots,
862 #endif
863 };
864 
865 static const struct export_operations jfs_export_operations = {
866 	.fh_to_dentry	= jfs_fh_to_dentry,
867 	.fh_to_parent	= jfs_fh_to_parent,
868 	.get_parent	= jfs_get_parent,
869 };
870 
871 static struct file_system_type jfs_fs_type = {
872 	.owner		= THIS_MODULE,
873 	.name		= "jfs",
874 	.mount		= jfs_do_mount,
875 	.kill_sb	= kill_block_super,
876 	.fs_flags	= FS_REQUIRES_DEV,
877 };
878 MODULE_ALIAS_FS("jfs");
879 
880 static void init_once(void *foo)
881 {
882 	struct jfs_inode_info *jfs_ip = (struct jfs_inode_info *) foo;
883 
884 	memset(jfs_ip, 0, sizeof(struct jfs_inode_info));
885 	INIT_LIST_HEAD(&jfs_ip->anon_inode_list);
886 	init_rwsem(&jfs_ip->rdwrlock);
887 	mutex_init(&jfs_ip->commit_mutex);
888 	init_rwsem(&jfs_ip->xattr_sem);
889 	spin_lock_init(&jfs_ip->ag_lock);
890 	jfs_ip->active_ag = -1;
891 	inode_init_once(&jfs_ip->vfs_inode);
892 }
893 
894 static int __init init_jfs_fs(void)
895 {
896 	int i;
897 	int rc;
898 
899 	jfs_inode_cachep =
900 	    kmem_cache_create("jfs_ip", sizeof(struct jfs_inode_info), 0,
901 			    SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|SLAB_ACCOUNT,
902 			    init_once);
903 	if (jfs_inode_cachep == NULL)
904 		return -ENOMEM;
905 
906 	/*
907 	 * Metapage initialization
908 	 */
909 	rc = metapage_init();
910 	if (rc) {
911 		jfs_err("metapage_init failed w/rc = %d", rc);
912 		goto free_slab;
913 	}
914 
915 	/*
916 	 * Transaction Manager initialization
917 	 */
918 	rc = txInit();
919 	if (rc) {
920 		jfs_err("txInit failed w/rc = %d", rc);
921 		goto free_metapage;
922 	}
923 
924 	/*
925 	 * I/O completion thread (endio)
926 	 */
927 	jfsIOthread = kthread_run(jfsIOWait, NULL, "jfsIO");
928 	if (IS_ERR(jfsIOthread)) {
929 		rc = PTR_ERR(jfsIOthread);
930 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
931 		goto end_txmngr;
932 	}
933 
934 	if (commit_threads < 1)
935 		commit_threads = num_online_cpus();
936 	if (commit_threads > MAX_COMMIT_THREADS)
937 		commit_threads = MAX_COMMIT_THREADS;
938 
939 	for (i = 0; i < commit_threads; i++) {
940 		jfsCommitThread[i] = kthread_run(jfs_lazycommit, NULL,
941 						 "jfsCommit");
942 		if (IS_ERR(jfsCommitThread[i])) {
943 			rc = PTR_ERR(jfsCommitThread[i]);
944 			jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
945 			commit_threads = i;
946 			goto kill_committask;
947 		}
948 	}
949 
950 	jfsSyncThread = kthread_run(jfs_sync, NULL, "jfsSync");
951 	if (IS_ERR(jfsSyncThread)) {
952 		rc = PTR_ERR(jfsSyncThread);
953 		jfs_err("init_jfs_fs: fork failed w/rc = %d", rc);
954 		goto kill_committask;
955 	}
956 
957 #ifdef PROC_FS_JFS
958 	jfs_proc_init();
959 #endif
960 
961 	rc = register_filesystem(&jfs_fs_type);
962 	if (!rc)
963 		return 0;
964 
965 #ifdef PROC_FS_JFS
966 	jfs_proc_clean();
967 #endif
968 	kthread_stop(jfsSyncThread);
969 kill_committask:
970 	for (i = 0; i < commit_threads; i++)
971 		kthread_stop(jfsCommitThread[i]);
972 	kthread_stop(jfsIOthread);
973 end_txmngr:
974 	txExit();
975 free_metapage:
976 	metapage_exit();
977 free_slab:
978 	kmem_cache_destroy(jfs_inode_cachep);
979 	return rc;
980 }
981 
982 static void __exit exit_jfs_fs(void)
983 {
984 	int i;
985 
986 	jfs_info("exit_jfs_fs called");
987 
988 	txExit();
989 	metapage_exit();
990 
991 	kthread_stop(jfsIOthread);
992 	for (i = 0; i < commit_threads; i++)
993 		kthread_stop(jfsCommitThread[i]);
994 	kthread_stop(jfsSyncThread);
995 #ifdef PROC_FS_JFS
996 	jfs_proc_clean();
997 #endif
998 	unregister_filesystem(&jfs_fs_type);
999 
1000 	/*
1001 	 * Make sure all delayed rcu free inodes are flushed before we
1002 	 * destroy cache.
1003 	 */
1004 	rcu_barrier();
1005 	kmem_cache_destroy(jfs_inode_cachep);
1006 }
1007 
1008 module_init(init_jfs_fs)
1009 module_exit(exit_jfs_fs)
1010