summaryrefslogtreecommitdiffstats
path: root/fs/jffs2/fs.c
blob: 3eb1c84b0a33289b62dfef1dd21d774647302d64 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */

#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/mtd/mtd.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/vfs.h>
#include <linux/crc32.h>
#include "nodelist.h"

static int jffs2_flash_setup(struct jffs2_sb_info *c);

int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
{
	struct jffs2_full_dnode *old_metadata, *new_metadata;
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	struct jffs2_raw_inode *ri;
	union jffs2_device_node dev;
	unsigned char *mdata = NULL;
	int mdatalen = 0;
	unsigned int ivalid;
	uint32_t alloclen;
	int ret;
	int alloc_type = ALLOC_NORMAL;

	D1(printk(KERN_DEBUG "jffs2_setattr(): ino #%lu\n", inode->i_ino));

	/* Special cases - we don't want more than one data node
	   for these types on the medium at any time. So setattr
	   must read the original data associated with the node
	   (i.e. the device numbers or the target name) and write
	   it out again with the appropriate data attached */
	if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
		/* For these, we don't actually need to read the old node */
		mdatalen = jffs2_encode_dev(&dev, inode->i_rdev);
		mdata = (char *)&dev;
		D1(printk(KERN_DEBUG "jffs2_setattr(): Writing %d bytes of kdev_t\n", mdatalen));
	} else if (S_ISLNK(inode->i_mode)) {
		mutex_lock(&f->sem);
		mdatalen = f->metadata->size;
		mdata = kmalloc(f->metadata->size, GFP_USER);
		if (!mdata) {
			mutex_unlock(&f->sem);
			return -ENOMEM;
		}
		ret = jffs2_read_dnode(c, f, f->metadata, mdata, 0, mdatalen);
		if (ret) {
			mutex_unlock(&f->sem);
			kfree(mdata);
			return ret;
		}
		mutex_unlock(&f->sem);
		D1(printk(KERN_DEBUG "jffs2_setattr(): Writing %d bytes of symlink target\n", mdatalen));
	}

	ri = jffs2_alloc_raw_inode();
	if (!ri) {
		if (S_ISLNK(inode->i_mode))
			kfree(mdata);
		return -ENOMEM;
	}

	ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &alloclen,
				  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
	if (ret) {
		jffs2_free_raw_inode(ri);
		if (S_ISLNK(inode->i_mode & S_IFMT))
			 kfree(mdata);
		return ret;
	}
	mutex_lock(&f->sem);
	ivalid = iattr->ia_valid;

	ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
	ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
	ri->totlen = cpu_to_je32(sizeof(*ri) + mdatalen);
	ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));

	ri->ino = cpu_to_je32(inode->i_ino);
	ri->version = cpu_to_je32(++f->highest_version);

	ri->uid = cpu_to_je16((ivalid & ATTR_UID)?iattr->ia_uid:inode->i_uid);
	ri->gid = cpu_to_je16((ivalid & ATTR_GID)?iattr->ia_gid:inode->i_gid);

	if (ivalid & ATTR_MODE)
		ri->mode = cpu_to_jemode(iattr->ia_mode);
	else
		ri->mode = cpu_to_jemode(inode->i_mode);


	ri->isize = cpu_to_je32((ivalid & ATTR_SIZE)?iattr->ia_size:inode->i_size);
	ri->atime = cpu_to_je32(I_SEC((ivalid & ATTR_ATIME)?iattr->ia_atime:inode->i_atime));
	ri->mtime = cpu_to_je32(I_SEC((ivalid & ATTR_MTIME)?iattr->ia_mtime:inode->i_mtime));
	ri->ctime = cpu_to_je32(I_SEC((ivalid & ATTR_CTIME)?iattr->ia_ctime:inode->i_ctime));

	ri->offset = cpu_to_je32(0);
	ri->csize = ri->dsize = cpu_to_je32(mdatalen);
	ri->compr = JFFS2_COMPR_NONE;
	if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
		/* It's an extension. Make it a hole node */
		ri->compr = JFFS2_COMPR_ZERO;
		ri->dsize = cpu_to_je32(iattr->ia_size - inode->i_size);
		ri->offset = cpu_to_je32(inode->i_size);
	} else if (ivalid & ATTR_SIZE && !iattr->ia_size) {
		/* For truncate-to-zero, treat it as deletion because
		   it'll always be obsoleting all previous nodes */
		alloc_type = ALLOC_DELETION;
	}
	ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
	if (mdatalen)
		ri->data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
	else
		ri->data_crc = cpu_to_je32(0);

	new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, alloc_type);
	if (S_ISLNK(inode->i_mode))
		kfree(mdata);

	if (IS_ERR(new_metadata)) {
		jffs2_complete_reservation(c);
		jffs2_free_raw_inode(ri);
		mutex_unlock(&f->sem);
		return PTR_ERR(new_metadata);
	}
	/* It worked. Update the inode */
	inode->i_atime = ITIME(je32_to_cpu(ri->atime));
	inode->i_ctime = ITIME(je32_to_cpu(ri->ctime));
	inode->i_mtime = ITIME(je32_to_cpu(ri->mtime));
	inode->i_mode = jemode_to_cpu(ri->mode);
	inode->i_uid = je16_to_cpu(ri->uid);
	inode->i_gid = je16_to_cpu(ri->gid);


	old_metadata = f->metadata;

	if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size)
		jffs2_truncate_fragtree (c, &f->fragtree, iattr->ia_size);

	if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
		jffs2_add_full_dnode_to_inode(c, f, new_metadata);
		inode->i_size = iattr->ia_size;
		inode->i_blocks = (inode->i_size + 511) >> 9;
		f->metadata = NULL;
	} else {
		f->metadata = new_metadata;
	}
	if (old_metadata) {
		jffs2_mark_node_obsolete(c, old_metadata->raw);
		jffs2_free_full_dnode(old_metadata);
	}
	jffs2_free_raw_inode(ri);

	mutex_unlock(&f->sem);
	jffs2_complete_reservation(c);

	/* We have to do the vmtruncate() without f->sem held, since
	   some pages may be locked and waiting for it in readpage().
	   We are protected from a simultaneous write() extending i_size
	   back past iattr->ia_size, because do_truncate() holds the
	   generic inode semaphore. */
	if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
		vmtruncate(inode, iattr->ia_size);	
		inode->i_blocks = (inode->i_size + 511) >> 9;
	}	

	return 0;
}

int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
{
	int rc;

	rc = inode_change_ok(dentry->d_inode, iattr);
	if (rc)
		return rc;

	rc = jffs2_do_setattr(dentry->d_inode, iattr);
	if (!rc && (iattr->ia_valid & ATTR_MODE))
		rc = jffs2_acl_chmod(dentry->d_inode);

	return rc;
}

int jffs2_statfs(struct dentry *dentry, struct kstatfs *buf)
{
	struct jffs2_sb_info *c = JFFS2_SB_INFO(dentry->d_sb);
	unsigned long avail;

	buf->f_type = JFFS2_SUPER_MAGIC;
	buf->f_bsize = 1 << PAGE_SHIFT;
	buf->f_blocks = c->flash_size >> PAGE_SHIFT;
	buf->f_files = 0;
	buf->f_ffree = 0;
	buf->f_namelen = JFFS2_MAX_NAME_LEN;

	spin_lock(&c->erase_completion_lock);
	avail = c->dirty_size + c->free_size;
	if (avail > c->sector_size * c->resv_blocks_write)
		avail -= c->sector_size * c->resv_blocks_write;
	else
		avail = 0;
	spin_unlock(&c->erase_completion_lock);

	buf->f_bavail = buf->f_bfree = avail >> PAGE_SHIFT;

	return 0;
}


void jffs2_clear_inode (struct inode *inode)
{
	/* We can forget about this inode for now - drop all
	 *  the nodelists associated with it, etc.
	 */
	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);

	D1(printk(KERN_DEBUG "jffs2_clear_inode(): ino #%lu mode %o\n", inode->i_ino, inode->i_mode));
	jffs2_do_clear_inode(c, f);
}

struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
{
	struct jffs2_inode_info *f;
	struct jffs2_sb_info *c;
	struct jffs2_raw_inode latest_node;
	union jffs2_device_node jdev;
	struct inode *inode;
	dev_t rdev = 0;
	int ret;

	D1(printk(KERN_DEBUG "jffs2_iget(): ino == %lu\n", ino));

	inode = iget_locked(sb, ino);
	if (!inode)
		return ERR_PTR(-ENOMEM);
	if (!(inode->i_state & I_NEW))
		return inode;

	f = JFFS2_INODE_INFO(inode);
	c = JFFS2_SB_INFO(inode->i_sb);

	jffs2_init_inode_info(f);
	mutex_lock(&f->sem);

	ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);

	if (ret) {
		mutex_unlock(&f->sem);
		iget_failed(inode);
		return ERR_PTR(ret);
	}
	inode->i_mode = jemode_to_cpu(latest_node.mode);
	inode->i_uid = je16_to_cpu(latest_node.uid);
	inode->i_gid = je16_to_cpu(latest_node.gid);
	inode->i_size = je32_to_cpu(latest_node.isize);
	inode->i_atime = ITIME(je32_to_cpu(latest_node.atime));
	inode->i_mtime = ITIME(je32_to_cpu(latest_node.mtime));
	inode->i_ctime = ITIME(je32_to_cpu(latest_node.ctime));

	inode->i_nlink = f->inocache->nlink;

	inode->i_blocks = (inode->i_size + 511) >> 9;

	switch (inode->i_mode & S_IFMT) {

	case S_IFLNK:
		inode->i_op = &jffs2_symlink_inode_operations;
		break;

	case S_IFDIR:
	{
		struct jffs2_full_dirent *fd;

		for (fd=f->dents; fd; fd = fd->next) {
			if (fd->type == DT_DIR && fd->ino)
				inc_nlink(inode);
		}
		/* and '..' */
		inc_nlink(inode);
		/* Root dir gets i_nlink 3 for some reason */
		if (inode->i_ino == 1)
			inc_nlink(inode);

		inode->i_op = &jffs2_dir_inode_operations;
		inode->i_fop = &jffs2_dir_operations;
		break;
	}
	case S_IFREG:
		inode->i_op = &jffs2_file_inode_operations;
		inode->i_fop = &jffs2_file_operations;
		inode->i_mapping->a_ops = &jffs2_file_address_operations;
		inode->i_mapping->nrpages = 0;
		break;

	case S_IFBLK:
	case S_IFCHR:
		/* Read the device numbers from the media */
		if (f->metadata->size != sizeof(jdev.old) &&
		    f->metadata->size != sizeof(jdev.new)) {
			printk(KERN_NOTICE "Device node has strange size %d\n", f->metadata->size);
			goto error_io;
		}
		D1(printk(KERN_DEBUG "Reading device numbers from flash\n"));
		ret = jffs2_read_dnode(c, f, f->metadata, (char *)&jdev, 0, f->metadata->size);
		if (ret < 0) {
			/* Eep */
			printk(KERN_NOTICE "Read device numbers for inode %lu failed\n", (unsigned long)inode->i_ino);
			goto error;
		}
		if (f->metadata->size == sizeof(jdev.old))
			rdev = old_decode_dev(je16_to_cpu(jdev.old));
		else
			rdev = new_decode_dev(je32_to_cpu(jdev.new));

	case S_IFSOCK:
	case S_IFIFO:
		inode->i_op = &jffs2_file_inode_operations;
		init_special_inode(inode, inode->i_mode, rdev);
		break;

	default:
		printk(KERN_WARNING "jffs2_read_inode(): Bogus imode %o for ino %lu\n", inode->i_mode, (unsigned long)inode->i_ino);
	}

	mutex_unlock(&f->sem);

	D1(printk(KERN_DEBUG "jffs2_read_inode() returning\n"));
	unlock_new_inode(inode);
	return inode;

error_io:
	ret = -EIO;
error:
	mutex_unlock(&f->sem);
	jffs2_do_clear_inode(c, f);
	iget_failed(inode);
	return ERR_PTR(ret);
}

void jffs2_dirty_inode(struct inode *inode)
{
	struct iattr iattr;

	if (!(inode->i_state & I_DIRTY_DATASYNC)) {
		D2(printk(KERN_DEBUG "jffs2_dirty_inode() not calling setattr() for ino #%lu\n", inode->i_ino));
		return;
	}

	D1(printk(KERN_DEBUG "jffs2_dirty_inode() calling setattr() for ino #%lu\n", inode->i_ino));

	iattr.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_MTIME|ATTR_CTIME;
	iattr.ia_mode = inode->i_mode;
	iattr.ia_uid = inode->i_uid;
	iattr.ia_gid = inode->i_gid;
	iattr.ia_atime = inode->i_atime;
	iattr.ia_mtime = inode->i_mtime;
	iattr.ia_ctime = inode->i_ctime;

	jffs2_do_setattr(inode, &iattr);
}

int jffs2_remount_fs (struct super_block *sb, int *flags, char *data)
{
	struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);

	if (c->flags & JFFS2_SB_FLAG_RO && !(sb->s_flags & MS_RDONLY))
		return -EROFS;

	/* We stop if it was running, then restart if it needs to.
	   This also catches the case where it was stopped and this
	   is just a remount to restart it.
	   Flush the writebuffer, if neccecary, else we loose it */
	if (!(sb->s_flags & MS_RDONLY)) {
		jffs2_stop_garbage_collect_thread(c);
		mutex_lock(&c->alloc_sem);
		jffs2_flush_wbuf_pad(c);
		mutex_unlock(&c->alloc_sem);
	}

	if (!(*flags & MS_RDONLY))
		jffs2_start_garbage_collect_thread(c);

	*flags |= MS_NOATIME;

	return 0;
}

void jffs2_write_super (struct super_block *sb)
{
	struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
	sb->s_dirt = 0;

	if (sb->s_flags & MS_RDONLY)
		return;

	D1(printk(KERN_DEBUG "jffs2_write_super()\n"));
	jffs2_garbage_collect_trigger(c);
	jffs2_erase_pending_blocks(c, 0);
	jffs2_flush_wbuf_gc(c, 0);
}


/* jffs2_new_inode: allocate a new inode and inocache, add it to the hash,
   fill in the raw_inode while you're at it. */
struct inode *jffs2_new_inode (struct inode *dir_i, int mode, struct jffs2_raw_inode *ri)
{
	struct inode *inode;
	struct super_block *sb = dir_i->i_sb;
	struct jffs2_sb_info *c;
	struct jffs2_inode_info *f;
	int ret;

	D1(printk(KERN_DEBUG "jffs2_new_inode(): dir_i %ld, mode 0x%x\n", dir_i->i_ino, mode));

	c = JFFS2_SB_INFO(sb);

	inode = new_inode(sb);

	if (!inode)
		return ERR_PTR(-ENOMEM);

	f = JFFS2_INODE_INFO(inode);
	jffs2_init_inode_info(f);
	mutex_lock(&f->sem);

	memset(ri, 0, sizeof(*ri));
	/* Set OS-specific defaults for new inodes */
	ri->uid = cpu_to_je16(current->fsuid);

	if (dir_i->i_mode & S_ISGID) {
		ri->gid = cpu_to_je16(dir_i->i_gid);
		if (S_ISDIR(mode))
			mode |= S_ISGID;
	} else {
		ri->gid = cpu_to_je16(current->fsgid);
	}

	/* POSIX ACLs have to be processed now, at least partly.
	   The umask is only applied if there's no default ACL */
	ret = jffs2_init_acl_pre(dir_i, inode, &mode);
	if (ret) {
	    make_bad_inode(inode);
	    iput(inode);
	    return ERR_PTR(ret);
	}
	ret = jffs2_do_new_inode (c, f, mode, ri);
	if (ret) {
		make_bad_inode(inode);
		iput(inode);
		return ERR_PTR(ret);
	}
	inode->i_nlink = 1;
	inode->i_ino = je32_to_cpu(ri->ino);
	inode->i_mode = jemode_to_cpu(ri->mode);
	inode->i_gid = je16_to_cpu(ri->gid);
	inode->i_uid = je16_to_cpu(ri->uid);
	inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
	ri->atime = ri->mtime = ri->ctime = cpu_to_je32(I_SEC(inode->i_mtime));

	inode->i_blocks = 0;
	inode->i_size = 0;

	insert_inode_hash(inode);

	return inode;
}


int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
{
	struct jffs2_sb_info *c;
	struct inode *root_i;
	int ret;
	size_t blocks;

	c = JFFS2_SB_INFO(sb);

#ifndef CONFIG_JFFS2_FS_WRITEBUFFER
	if (c->mtd->type == MTD_NANDFLASH) {
		printk(KERN_ERR "jffs2: Cannot operate on NAND flash unless jffs2 NAND support is compiled in.\n");
		return -EINVAL;
	}
	if (c->mtd->type == MTD_DATAFLASH) {
		printk(KERN_ERR "jffs2: Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in.\n");
		return -EINVAL;
	}
#endif

	c->flash_size = c->mtd->size;
	c->sector_size = c->mtd->erasesize;
	blocks = c->flash_size / c->sector_size;

	/*
	 * Size alignment check
	 */
	if ((c->sector_size * blocks) != c->flash_size) {
		c->flash_size = c->sector_size * blocks;
		printk(KERN_INFO "jffs2: Flash size not aligned to erasesize, reducing to %dKiB\n",
			c->flash_size / 1024);
	}

	if (c->flash_size < 5*c->sector_size) {
		printk(KERN_ERR "jffs2: Too few erase blocks (%d)\n", c->flash_size / c->sector_size);
		return -EINVAL;
	}

	c->cleanmarker_size = sizeof(struct jffs2_unknown_node);

	/* NAND (or other bizarre) flash... do setup accordingly */
	ret = jffs2_flash_setup(c);
	if (ret)
		return ret;

	c->inocache_list = kcalloc(INOCACHE_HASHSIZE, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
	if (!c->inocache_list) {
		ret = -ENOMEM;
		goto out_wbuf;
	}

	jffs2_init_xattr_subsystem(c);

	if ((ret = jffs2_do_mount_fs(c)))
		goto out_inohash;

	D1(printk(KERN_DEBUG "jffs2_do_fill_super(): Getting root inode\n"));
	root_i = jffs2_iget(sb, 1);
	if (IS_ERR(root_i)) {
		D1(printk(KERN_WARNING "get root inode failed\n"));
		ret = PTR_ERR(root_i);
		goto out_root;
	}

	ret = -ENOMEM;

	D1(printk(KERN_DEBUG "jffs2_do_fill_super(): d_alloc_root()\n"));
	sb->s_root = d_alloc_root(root_i);
	if (!sb->s_root)
		goto out_root_i;

	sb->s_maxbytes = 0xFFFFFFFF;
	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = JFFS2_SUPER_MAGIC;
	if (!(sb->s_flags & MS_RDONLY))
		jffs2_start_garbage_collect_thread(c);
	return 0;

 out_root_i:
	iput(root_i);
out_root:
	jffs2_free_ino_caches(c);
	jffs2_free_raw_node_refs(c);
	if (jffs2_blocks_use_vmalloc(c))
		vfree(c->blocks);
	else
		kfree(c->blocks);
 out_inohash:
	jffs2_clear_xattr_subsystem(c);
	kfree(c->inocache_list);
 out_wbuf:
	jffs2_flash_cleanup(c);

	return ret;
}

void jffs2_gc_release_inode(struct jffs2_sb_info *c,
				   struct jffs2_inode_info *f)
{
	iput(OFNI_EDONI_2SFFJ(f));
}

struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
						     int inum, int nlink)
{
	struct inode *inode;
	struct jffs2_inode_cache *ic;
	if (!nlink) {
		/* The inode has zero nlink but its nodes weren't yet marked
		   obsolete. This has to be because we're still waiting for
		   the final (close() and) iput() to happen.

		   There's a possibility that the final iput() could have
		   happened while we were contemplating. In order to ensure
		   that we don't cause a new read_inode() (which would fail)
		   for the inode in question, we use ilookup() in this case
		   instead of iget().

		   The nlink can't _become_ zero at this point because we're
		   holding the alloc_sem, and jffs2_do_unlink() would also
		   need that while decrementing nlink on any inode.
		*/
		inode = ilookup(OFNI_BS_2SFFJ(c), inum);
		if (!inode) {
			D1(printk(KERN_DEBUG "ilookup() failed for ino #%u; inode is probably deleted.\n",
				  inum));

			spin_lock(&c->inocache_lock);
			ic = jffs2_get_ino_cache(c, inum);
			if (!ic) {
				D1(printk(KERN_DEBUG "Inode cache for ino #%u is gone.\n", inum));
				spin_unlock(&c->inocache_lock);
				return NULL;
			}
			if (ic->state != INO_STATE_CHECKEDABSENT) {
				/* Wait for progress. Don't just loop */
				D1(printk(KERN_DEBUG "Waiting for ino #%u in state %d\n",
					  ic->ino, ic->state));
				sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
			} else {
				spin_unlock(&c->inocache_lock);
			}

			return NULL;
		}
	} else {
		/* Inode has links to it still; they're not going away because
		   jffs2_do_unlink() would need the alloc_sem and we have it.
		   Just iget() it, and if read_inode() is necessary that's OK.
		*/
		inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
		if (IS_ERR(inode))
			return ERR_CAST(inode);
	}
	if (is_bad_inode(inode)) {
		printk(KERN_NOTICE "Eep. read_inode() failed for ino #%u. nlink %d\n",
		       inum, nlink);
		/* NB. This will happen again. We need to do something appropriate here. */
		iput(inode);
		return ERR_PTR(-EIO);
	}

	return JFFS2_INODE_INFO(inode);
}

unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
				   struct jffs2_inode_info *f,
				   unsigned long offset,
				   unsigned long *priv)
{
	struct inode *inode = OFNI_EDONI_2SFFJ(f);
	struct page *pg;

	pg = read_cache_page_async(inode->i_mapping, offset >> PAGE_CACHE_SHIFT,
			     (void *)jffs2_do_readpage_unlock, inode);
	if (IS_ERR(pg))
		return (void *)pg;

	*priv = (unsigned long)pg;
	return kmap(pg);
}

void jffs2_gc_release_page(struct jffs2_sb_info *c,
			   unsigned char *ptr,
			   unsigned long *priv)
{
	struct page *pg = (void *)*priv;

	kunmap(pg);
	page_cache_release(pg);
}

static int jffs2_flash_setup(struct jffs2_sb_info *c) {
	int ret = 0;

	if (jffs2_cleanmarker_oob(c)) {
		/* NAND flash... do setup accordingly */
		ret = jffs2_nand_flash_setup(c);
		if (ret)
			return ret;
	}

	/* and Dataflash */
	if (jffs2_dataflash(c)) {
		ret = jffs2_dataflash_setup(c);
		if (ret)
			return ret;
	}

	/* and Intel "Sibley" flash */
	if (jffs2_nor_wbuf_flash(c)) {
		ret = jffs2_nor_wbuf_flash_setup(c);
		if (ret)
			return ret;
	}

	/* and an UBI volume */
	if (jffs2_ubivol(c)) {
		ret = jffs2_ubivol_setup(c);
		if (ret)
			return ret;
	}

	return ret;
}

void jffs2_flash_cleanup(struct jffs2_sb_info *c) {

	if (jffs2_cleanmarker_oob(c)) {
		jffs2_nand_flash_cleanup(c);
	}

	/* and DataFlash */
	if (jffs2_dataflash(c)) {
		jffs2_dataflash_cleanup(c);
	}

	/* and Intel "Sibley" flash */
	if (jffs2_nor_wbuf_flash(c)) {
		jffs2_nor_wbuf_flash_cleanup(c);
	}

	/* and an UBI volume */
	if (jffs2_ubivol(c)) {
		jffs2_ubivol_cleanup(c);
	}
}
OpenPOWER on IntegriCloud