xref: /openbmc/u-boot/fs/ubifs/super.c (revision a0a868b2)
1  /*
2   * This file is part of UBIFS.
3   *
4   * Copyright (C) 2006-2008 Nokia Corporation.
5   *
6   * SPDX-License-Identifier:	GPL-2.0+
7   *
8   * Authors: Artem Bityutskiy (Битюцкий Артём)
9   *          Adrian Hunter
10   */
11  
12  /*
13   * This file implements UBIFS initialization and VFS superblock operations. Some
14   * initialization stuff which is rather large and complex is placed at
15   * corresponding subsystems, but most of it is here.
16   */
17  
18  #ifndef __UBOOT__
19  #include <linux/init.h>
20  #include <linux/slab.h>
21  #include <linux/module.h>
22  #include <linux/ctype.h>
23  #include <linux/kthread.h>
24  #include <linux/parser.h>
25  #include <linux/seq_file.h>
26  #include <linux/mount.h>
27  #include <linux/math64.h>
28  #include <linux/writeback.h>
29  #else
30  
31  #include <common.h>
32  #include <malloc.h>
33  #include <memalign.h>
34  #include <linux/bug.h>
35  #include <linux/log2.h>
36  #include <linux/stat.h>
37  #include <linux/err.h>
38  #include "ubifs.h"
39  #include <ubi_uboot.h>
40  #include <mtd/ubi-user.h>
41  
42  struct dentry;
43  struct file;
44  struct iattr;
45  struct kstat;
46  struct vfsmount;
47  
48  #define INODE_LOCKED_MAX	64
49  
50  struct super_block *ubifs_sb;
51  
52  static struct inode *inodes_locked_down[INODE_LOCKED_MAX];
53  
54  int set_anon_super(struct super_block *s, void *data)
55  {
56  	return 0;
57  }
58  
59  struct inode *iget_locked(struct super_block *sb, unsigned long ino)
60  {
61  	struct inode *inode;
62  
63  	inode = (struct inode *)malloc_cache_aligned(
64  			sizeof(struct ubifs_inode));
65  	if (inode) {
66  		inode->i_ino = ino;
67  		inode->i_sb = sb;
68  		list_add(&inode->i_sb_list, &sb->s_inodes);
69  		inode->i_state = I_LOCK | I_NEW;
70  	}
71  
72  	return inode;
73  }
74  
75  void iget_failed(struct inode *inode)
76  {
77  }
78  
79  int ubifs_iput(struct inode *inode)
80  {
81  	list_del_init(&inode->i_sb_list);
82  
83  	free(inode);
84  	return 0;
85  }
86  
87  /*
88   * Lock (save) inode in inode array for readback after recovery
89   */
90  void iput(struct inode *inode)
91  {
92  	int i;
93  	struct inode *ino;
94  
95  	/*
96  	 * Search end of list
97  	 */
98  	for (i = 0; i < INODE_LOCKED_MAX; i++) {
99  		if (inodes_locked_down[i] == NULL)
100  			break;
101  	}
102  
103  	if (i >= INODE_LOCKED_MAX) {
104  		dbg_gen("Error, can't lock (save) more inodes while recovery!!!");
105  		return;
106  	}
107  
108  	/*
109  	 * Allocate and use new inode
110  	 */
111  	ino = (struct inode *)malloc_cache_aligned(sizeof(struct ubifs_inode));
112  	memcpy(ino, inode, sizeof(struct ubifs_inode));
113  
114  	/*
115  	 * Finally save inode in array
116  	 */
117  	inodes_locked_down[i] = ino;
118  }
119  
120  /* from fs/inode.c */
121  /**
122   * clear_nlink - directly zero an inode's link count
123   * @inode: inode
124   *
125   * This is a low-level filesystem helper to replace any
126   * direct filesystem manipulation of i_nlink.  See
127   * drop_nlink() for why we care about i_nlink hitting zero.
128   */
129  void clear_nlink(struct inode *inode)
130  {
131  	if (inode->i_nlink) {
132  		inode->__i_nlink = 0;
133  		atomic_long_inc(&inode->i_sb->s_remove_count);
134  	}
135  }
136  EXPORT_SYMBOL(clear_nlink);
137  
138  /**
139   * set_nlink - directly set an inode's link count
140   * @inode: inode
141   * @nlink: new nlink (should be non-zero)
142   *
143   * This is a low-level filesystem helper to replace any
144   * direct filesystem manipulation of i_nlink.
145   */
146  void set_nlink(struct inode *inode, unsigned int nlink)
147  {
148  	if (!nlink) {
149  		clear_nlink(inode);
150  	} else {
151  		/* Yes, some filesystems do change nlink from zero to one */
152  		if (inode->i_nlink == 0)
153  			atomic_long_dec(&inode->i_sb->s_remove_count);
154  
155  		inode->__i_nlink = nlink;
156  	}
157  }
158  EXPORT_SYMBOL(set_nlink);
159  
160  /* from include/linux/fs.h */
161  static inline void i_uid_write(struct inode *inode, uid_t uid)
162  {
163  	inode->i_uid.val = uid;
164  }
165  
166  static inline void i_gid_write(struct inode *inode, gid_t gid)
167  {
168  	inode->i_gid.val = gid;
169  }
170  
171  void unlock_new_inode(struct inode *inode)
172  {
173  	return;
174  }
175  #endif
176  
177  /*
178   * Maximum amount of memory we may 'kmalloc()' without worrying that we are
179   * allocating too much.
180   */
181  #define UBIFS_KMALLOC_OK (128*1024)
182  
183  /* Slab cache for UBIFS inodes */
184  struct kmem_cache *ubifs_inode_slab;
185  
186  #ifndef __UBOOT__
187  /* UBIFS TNC shrinker description */
188  static struct shrinker ubifs_shrinker_info = {
189  	.scan_objects = ubifs_shrink_scan,
190  	.count_objects = ubifs_shrink_count,
191  	.seeks = DEFAULT_SEEKS,
192  };
193  #endif
194  
195  /**
196   * validate_inode - validate inode.
197   * @c: UBIFS file-system description object
198   * @inode: the inode to validate
199   *
200   * This is a helper function for 'ubifs_iget()' which validates various fields
201   * of a newly built inode to make sure they contain sane values and prevent
202   * possible vulnerabilities. Returns zero if the inode is all right and
203   * a non-zero error code if not.
204   */
205  static int validate_inode(struct ubifs_info *c, const struct inode *inode)
206  {
207  	int err;
208  	const struct ubifs_inode *ui = ubifs_inode(inode);
209  
210  	if (inode->i_size > c->max_inode_sz) {
211  		ubifs_err(c, "inode is too large (%lld)",
212  			  (long long)inode->i_size);
213  		return 1;
214  	}
215  
216  	if (ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
217  		ubifs_err(c, "unknown compression type %d", ui->compr_type);
218  		return 2;
219  	}
220  
221  	if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
222  		return 3;
223  
224  	if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
225  		return 4;
226  
227  	if (ui->xattr && !S_ISREG(inode->i_mode))
228  		return 5;
229  
230  	if (!ubifs_compr_present(ui->compr_type)) {
231  		ubifs_warn(c, "inode %lu uses '%s' compression, but it was not compiled in",
232  			   inode->i_ino, ubifs_compr_name(ui->compr_type));
233  	}
234  
235  	err = dbg_check_dir(c, inode);
236  	return err;
237  }
238  
239  struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
240  {
241  	int err;
242  	union ubifs_key key;
243  	struct ubifs_ino_node *ino;
244  	struct ubifs_info *c = sb->s_fs_info;
245  	struct inode *inode;
246  	struct ubifs_inode *ui;
247  #ifdef __UBOOT__
248  	int i;
249  #endif
250  
251  	dbg_gen("inode %lu", inum);
252  
253  #ifdef __UBOOT__
254  	/*
255  	 * U-Boot special handling of locked down inodes via recovery
256  	 * e.g. ubifs_recover_size()
257  	 */
258  	for (i = 0; i < INODE_LOCKED_MAX; i++) {
259  		/*
260  		 * Exit on last entry (NULL), inode not found in list
261  		 */
262  		if (inodes_locked_down[i] == NULL)
263  			break;
264  
265  		if (inodes_locked_down[i]->i_ino == inum) {
266  			/*
267  			 * We found the locked down inode in our array,
268  			 * so just return this pointer instead of creating
269  			 * a new one.
270  			 */
271  			return inodes_locked_down[i];
272  		}
273  	}
274  #endif
275  
276  	inode = iget_locked(sb, inum);
277  	if (!inode)
278  		return ERR_PTR(-ENOMEM);
279  	if (!(inode->i_state & I_NEW))
280  		return inode;
281  	ui = ubifs_inode(inode);
282  
283  	ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
284  	if (!ino) {
285  		err = -ENOMEM;
286  		goto out;
287  	}
288  
289  	ino_key_init(c, &key, inode->i_ino);
290  
291  	err = ubifs_tnc_lookup(c, &key, ino);
292  	if (err)
293  		goto out_ino;
294  
295  	inode->i_flags |= (S_NOCMTIME | S_NOATIME);
296  	set_nlink(inode, le32_to_cpu(ino->nlink));
297  	i_uid_write(inode, le32_to_cpu(ino->uid));
298  	i_gid_write(inode, le32_to_cpu(ino->gid));
299  	inode->i_atime.tv_sec  = (int64_t)le64_to_cpu(ino->atime_sec);
300  	inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
301  	inode->i_mtime.tv_sec  = (int64_t)le64_to_cpu(ino->mtime_sec);
302  	inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
303  	inode->i_ctime.tv_sec  = (int64_t)le64_to_cpu(ino->ctime_sec);
304  	inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
305  	inode->i_mode = le32_to_cpu(ino->mode);
306  	inode->i_size = le64_to_cpu(ino->size);
307  
308  	ui->data_len    = le32_to_cpu(ino->data_len);
309  	ui->flags       = le32_to_cpu(ino->flags);
310  	ui->compr_type  = le16_to_cpu(ino->compr_type);
311  	ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
312  	ui->xattr_cnt   = le32_to_cpu(ino->xattr_cnt);
313  	ui->xattr_size  = le32_to_cpu(ino->xattr_size);
314  	ui->xattr_names = le32_to_cpu(ino->xattr_names);
315  	ui->synced_i_size = ui->ui_size = inode->i_size;
316  
317  	ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
318  
319  	err = validate_inode(c, inode);
320  	if (err)
321  		goto out_invalid;
322  
323  #ifndef __UBOOT__
324  	switch (inode->i_mode & S_IFMT) {
325  	case S_IFREG:
326  		inode->i_mapping->a_ops = &ubifs_file_address_operations;
327  		inode->i_op = &ubifs_file_inode_operations;
328  		inode->i_fop = &ubifs_file_operations;
329  		if (ui->xattr) {
330  			ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
331  			if (!ui->data) {
332  				err = -ENOMEM;
333  				goto out_ino;
334  			}
335  			memcpy(ui->data, ino->data, ui->data_len);
336  			((char *)ui->data)[ui->data_len] = '\0';
337  		} else if (ui->data_len != 0) {
338  			err = 10;
339  			goto out_invalid;
340  		}
341  		break;
342  	case S_IFDIR:
343  		inode->i_op  = &ubifs_dir_inode_operations;
344  		inode->i_fop = &ubifs_dir_operations;
345  		if (ui->data_len != 0) {
346  			err = 11;
347  			goto out_invalid;
348  		}
349  		break;
350  	case S_IFLNK:
351  		inode->i_op = &ubifs_symlink_inode_operations;
352  		if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
353  			err = 12;
354  			goto out_invalid;
355  		}
356  		ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
357  		if (!ui->data) {
358  			err = -ENOMEM;
359  			goto out_ino;
360  		}
361  		memcpy(ui->data, ino->data, ui->data_len);
362  		((char *)ui->data)[ui->data_len] = '\0';
363  		inode->i_link = ui->data;
364  		break;
365  	case S_IFBLK:
366  	case S_IFCHR:
367  	{
368  		dev_t rdev;
369  		union ubifs_dev_desc *dev;
370  
371  		ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
372  		if (!ui->data) {
373  			err = -ENOMEM;
374  			goto out_ino;
375  		}
376  
377  		dev = (union ubifs_dev_desc *)ino->data;
378  		if (ui->data_len == sizeof(dev->new))
379  			rdev = new_decode_dev(le32_to_cpu(dev->new));
380  		else if (ui->data_len == sizeof(dev->huge))
381  			rdev = huge_decode_dev(le64_to_cpu(dev->huge));
382  		else {
383  			err = 13;
384  			goto out_invalid;
385  		}
386  		memcpy(ui->data, ino->data, ui->data_len);
387  		inode->i_op = &ubifs_file_inode_operations;
388  		init_special_inode(inode, inode->i_mode, rdev);
389  		break;
390  	}
391  	case S_IFSOCK:
392  	case S_IFIFO:
393  		inode->i_op = &ubifs_file_inode_operations;
394  		init_special_inode(inode, inode->i_mode, 0);
395  		if (ui->data_len != 0) {
396  			err = 14;
397  			goto out_invalid;
398  		}
399  		break;
400  	default:
401  		err = 15;
402  		goto out_invalid;
403  	}
404  #else
405  	if ((inode->i_mode & S_IFMT) == S_IFLNK) {
406  		if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
407  			err = 12;
408  			goto out_invalid;
409  		}
410  		ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
411  		if (!ui->data) {
412  			err = -ENOMEM;
413  			goto out_ino;
414  		}
415  		memcpy(ui->data, ino->data, ui->data_len);
416  		((char *)ui->data)[ui->data_len] = '\0';
417  	}
418  #endif
419  
420  	kfree(ino);
421  #ifndef __UBOOT__
422  	ubifs_set_inode_flags(inode);
423  #endif
424  	unlock_new_inode(inode);
425  	return inode;
426  
427  out_invalid:
428  	ubifs_err(c, "inode %lu validation failed, error %d", inode->i_ino, err);
429  	ubifs_dump_node(c, ino);
430  	ubifs_dump_inode(c, inode);
431  	err = -EINVAL;
432  out_ino:
433  	kfree(ino);
434  out:
435  	ubifs_err(c, "failed to read inode %lu, error %d", inode->i_ino, err);
436  	iget_failed(inode);
437  	return ERR_PTR(err);
438  }
439  
440  static struct inode *ubifs_alloc_inode(struct super_block *sb)
441  {
442  	struct ubifs_inode *ui;
443  
444  	ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
445  	if (!ui)
446  		return NULL;
447  
448  	memset((void *)ui + sizeof(struct inode), 0,
449  	       sizeof(struct ubifs_inode) - sizeof(struct inode));
450  	mutex_init(&ui->ui_mutex);
451  	spin_lock_init(&ui->ui_lock);
452  	return &ui->vfs_inode;
453  };
454  
455  #ifndef __UBOOT__
456  static void ubifs_i_callback(struct rcu_head *head)
457  {
458  	struct inode *inode = container_of(head, struct inode, i_rcu);
459  	struct ubifs_inode *ui = ubifs_inode(inode);
460  	kmem_cache_free(ubifs_inode_slab, ui);
461  }
462  
463  static void ubifs_destroy_inode(struct inode *inode)
464  {
465  	struct ubifs_inode *ui = ubifs_inode(inode);
466  
467  	kfree(ui->data);
468  	call_rcu(&inode->i_rcu, ubifs_i_callback);
469  }
470  
471  /*
472   * Note, Linux write-back code calls this without 'i_mutex'.
473   */
474  static int ubifs_write_inode(struct inode *inode, struct writeback_control *wbc)
475  {
476  	int err = 0;
477  	struct ubifs_info *c = inode->i_sb->s_fs_info;
478  	struct ubifs_inode *ui = ubifs_inode(inode);
479  
480  	ubifs_assert(!ui->xattr);
481  	if (is_bad_inode(inode))
482  		return 0;
483  
484  	mutex_lock(&ui->ui_mutex);
485  	/*
486  	 * Due to races between write-back forced by budgeting
487  	 * (see 'sync_some_inodes()') and background write-back, the inode may
488  	 * have already been synchronized, do not do this again. This might
489  	 * also happen if it was synchronized in an VFS operation, e.g.
490  	 * 'ubifs_link()'.
491  	 */
492  	if (!ui->dirty) {
493  		mutex_unlock(&ui->ui_mutex);
494  		return 0;
495  	}
496  
497  	/*
498  	 * As an optimization, do not write orphan inodes to the media just
499  	 * because this is not needed.
500  	 */
501  	dbg_gen("inode %lu, mode %#x, nlink %u",
502  		inode->i_ino, (int)inode->i_mode, inode->i_nlink);
503  	if (inode->i_nlink) {
504  		err = ubifs_jnl_write_inode(c, inode);
505  		if (err)
506  			ubifs_err(c, "can't write inode %lu, error %d",
507  				  inode->i_ino, err);
508  		else
509  			err = dbg_check_inode_size(c, inode, ui->ui_size);
510  	}
511  
512  	ui->dirty = 0;
513  	mutex_unlock(&ui->ui_mutex);
514  	ubifs_release_dirty_inode_budget(c, ui);
515  	return err;
516  }
517  
518  static void ubifs_evict_inode(struct inode *inode)
519  {
520  	int err;
521  	struct ubifs_info *c = inode->i_sb->s_fs_info;
522  	struct ubifs_inode *ui = ubifs_inode(inode);
523  
524  	if (ui->xattr)
525  		/*
526  		 * Extended attribute inode deletions are fully handled in
527  		 * 'ubifs_removexattr()'. These inodes are special and have
528  		 * limited usage, so there is nothing to do here.
529  		 */
530  		goto out;
531  
532  	dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
533  	ubifs_assert(!atomic_read(&inode->i_count));
534  
535  	truncate_inode_pages_final(&inode->i_data);
536  
537  	if (inode->i_nlink)
538  		goto done;
539  
540  	if (is_bad_inode(inode))
541  		goto out;
542  
543  	ui->ui_size = inode->i_size = 0;
544  	err = ubifs_jnl_delete_inode(c, inode);
545  	if (err)
546  		/*
547  		 * Worst case we have a lost orphan inode wasting space, so a
548  		 * simple error message is OK here.
549  		 */
550  		ubifs_err(c, "can't delete inode %lu, error %d",
551  			  inode->i_ino, err);
552  
553  out:
554  	if (ui->dirty)
555  		ubifs_release_dirty_inode_budget(c, ui);
556  	else {
557  		/* We've deleted something - clean the "no space" flags */
558  		c->bi.nospace = c->bi.nospace_rp = 0;
559  		smp_wmb();
560  	}
561  done:
562  	clear_inode(inode);
563  }
564  #endif
565  
566  static void ubifs_dirty_inode(struct inode *inode, int flags)
567  {
568  	struct ubifs_inode *ui = ubifs_inode(inode);
569  
570  	ubifs_assert(mutex_is_locked(&ui->ui_mutex));
571  	if (!ui->dirty) {
572  		ui->dirty = 1;
573  		dbg_gen("inode %lu",  inode->i_ino);
574  	}
575  }
576  
577  #ifndef __UBOOT__
578  static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
579  {
580  	struct ubifs_info *c = dentry->d_sb->s_fs_info;
581  	unsigned long long free;
582  	__le32 *uuid = (__le32 *)c->uuid;
583  
584  	free = ubifs_get_free_space(c);
585  	dbg_gen("free space %lld bytes (%lld blocks)",
586  		free, free >> UBIFS_BLOCK_SHIFT);
587  
588  	buf->f_type = UBIFS_SUPER_MAGIC;
589  	buf->f_bsize = UBIFS_BLOCK_SIZE;
590  	buf->f_blocks = c->block_cnt;
591  	buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
592  	if (free > c->report_rp_size)
593  		buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
594  	else
595  		buf->f_bavail = 0;
596  	buf->f_files = 0;
597  	buf->f_ffree = 0;
598  	buf->f_namelen = UBIFS_MAX_NLEN;
599  	buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]);
600  	buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]);
601  	ubifs_assert(buf->f_bfree <= c->block_cnt);
602  	return 0;
603  }
604  
605  static int ubifs_show_options(struct seq_file *s, struct dentry *root)
606  {
607  	struct ubifs_info *c = root->d_sb->s_fs_info;
608  
609  	if (c->mount_opts.unmount_mode == 2)
610  		seq_puts(s, ",fast_unmount");
611  	else if (c->mount_opts.unmount_mode == 1)
612  		seq_puts(s, ",norm_unmount");
613  
614  	if (c->mount_opts.bulk_read == 2)
615  		seq_puts(s, ",bulk_read");
616  	else if (c->mount_opts.bulk_read == 1)
617  		seq_puts(s, ",no_bulk_read");
618  
619  	if (c->mount_opts.chk_data_crc == 2)
620  		seq_puts(s, ",chk_data_crc");
621  	else if (c->mount_opts.chk_data_crc == 1)
622  		seq_puts(s, ",no_chk_data_crc");
623  
624  	if (c->mount_opts.override_compr) {
625  		seq_printf(s, ",compr=%s",
626  			   ubifs_compr_name(c->mount_opts.compr_type));
627  	}
628  
629  	return 0;
630  }
631  
632  static int ubifs_sync_fs(struct super_block *sb, int wait)
633  {
634  	int i, err;
635  	struct ubifs_info *c = sb->s_fs_info;
636  
637  	/*
638  	 * Zero @wait is just an advisory thing to help the file system shove
639  	 * lots of data into the queues, and there will be the second
640  	 * '->sync_fs()' call, with non-zero @wait.
641  	 */
642  	if (!wait)
643  		return 0;
644  
645  	/*
646  	 * Synchronize write buffers, because 'ubifs_run_commit()' does not
647  	 * do this if it waits for an already running commit.
648  	 */
649  	for (i = 0; i < c->jhead_cnt; i++) {
650  		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
651  		if (err)
652  			return err;
653  	}
654  
655  	/*
656  	 * Strictly speaking, it is not necessary to commit the journal here,
657  	 * synchronizing write-buffers would be enough. But committing makes
658  	 * UBIFS free space predictions much more accurate, so we want to let
659  	 * the user be able to get more accurate results of 'statfs()' after
660  	 * they synchronize the file system.
661  	 */
662  	err = ubifs_run_commit(c);
663  	if (err)
664  		return err;
665  
666  	return ubi_sync(c->vi.ubi_num);
667  }
668  #endif
669  
670  /**
671   * init_constants_early - initialize UBIFS constants.
672   * @c: UBIFS file-system description object
673   *
674   * This function initialize UBIFS constants which do not need the superblock to
675   * be read. It also checks that the UBI volume satisfies basic UBIFS
676   * requirements. Returns zero in case of success and a negative error code in
677   * case of failure.
678   */
679  static int init_constants_early(struct ubifs_info *c)
680  {
681  	if (c->vi.corrupted) {
682  		ubifs_warn(c, "UBI volume is corrupted - read-only mode");
683  		c->ro_media = 1;
684  	}
685  
686  	if (c->di.ro_mode) {
687  		ubifs_msg(c, "read-only UBI device");
688  		c->ro_media = 1;
689  	}
690  
691  	if (c->vi.vol_type == UBI_STATIC_VOLUME) {
692  		ubifs_msg(c, "static UBI volume - read-only mode");
693  		c->ro_media = 1;
694  	}
695  
696  	c->leb_cnt = c->vi.size;
697  	c->leb_size = c->vi.usable_leb_size;
698  	c->leb_start = c->di.leb_start;
699  	c->half_leb_size = c->leb_size / 2;
700  	c->min_io_size = c->di.min_io_size;
701  	c->min_io_shift = fls(c->min_io_size) - 1;
702  	c->max_write_size = c->di.max_write_size;
703  	c->max_write_shift = fls(c->max_write_size) - 1;
704  
705  	if (c->leb_size < UBIFS_MIN_LEB_SZ) {
706  		ubifs_err(c, "too small LEBs (%d bytes), min. is %d bytes",
707  			  c->leb_size, UBIFS_MIN_LEB_SZ);
708  		return -EINVAL;
709  	}
710  
711  	if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
712  		ubifs_err(c, "too few LEBs (%d), min. is %d",
713  			  c->leb_cnt, UBIFS_MIN_LEB_CNT);
714  		return -EINVAL;
715  	}
716  
717  	if (!is_power_of_2(c->min_io_size)) {
718  		ubifs_err(c, "bad min. I/O size %d", c->min_io_size);
719  		return -EINVAL;
720  	}
721  
722  	/*
723  	 * Maximum write size has to be greater or equivalent to min. I/O
724  	 * size, and be multiple of min. I/O size.
725  	 */
726  	if (c->max_write_size < c->min_io_size ||
727  	    c->max_write_size % c->min_io_size ||
728  	    !is_power_of_2(c->max_write_size)) {
729  		ubifs_err(c, "bad write buffer size %d for %d min. I/O unit",
730  			  c->max_write_size, c->min_io_size);
731  		return -EINVAL;
732  	}
733  
734  	/*
735  	 * UBIFS aligns all node to 8-byte boundary, so to make function in
736  	 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
737  	 * less than 8.
738  	 */
739  	if (c->min_io_size < 8) {
740  		c->min_io_size = 8;
741  		c->min_io_shift = 3;
742  		if (c->max_write_size < c->min_io_size) {
743  			c->max_write_size = c->min_io_size;
744  			c->max_write_shift = c->min_io_shift;
745  		}
746  	}
747  
748  	c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
749  	c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
750  
751  	/*
752  	 * Initialize node length ranges which are mostly needed for node
753  	 * length validation.
754  	 */
755  	c->ranges[UBIFS_PAD_NODE].len  = UBIFS_PAD_NODE_SZ;
756  	c->ranges[UBIFS_SB_NODE].len   = UBIFS_SB_NODE_SZ;
757  	c->ranges[UBIFS_MST_NODE].len  = UBIFS_MST_NODE_SZ;
758  	c->ranges[UBIFS_REF_NODE].len  = UBIFS_REF_NODE_SZ;
759  	c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
760  	c->ranges[UBIFS_CS_NODE].len   = UBIFS_CS_NODE_SZ;
761  
762  	c->ranges[UBIFS_INO_NODE].min_len  = UBIFS_INO_NODE_SZ;
763  	c->ranges[UBIFS_INO_NODE].max_len  = UBIFS_MAX_INO_NODE_SZ;
764  	c->ranges[UBIFS_ORPH_NODE].min_len =
765  				UBIFS_ORPH_NODE_SZ + sizeof(__le64);
766  	c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
767  	c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
768  	c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
769  	c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
770  	c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
771  	c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
772  	c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
773  	/*
774  	 * Minimum indexing node size is amended later when superblock is
775  	 * read and the key length is known.
776  	 */
777  	c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
778  	/*
779  	 * Maximum indexing node size is amended later when superblock is
780  	 * read and the fanout is known.
781  	 */
782  	c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
783  
784  	/*
785  	 * Initialize dead and dark LEB space watermarks. See gc.c for comments
786  	 * about these values.
787  	 */
788  	c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
789  	c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
790  
791  	/*
792  	 * Calculate how many bytes would be wasted at the end of LEB if it was
793  	 * fully filled with data nodes of maximum size. This is used in
794  	 * calculations when reporting free space.
795  	 */
796  	c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
797  
798  	/* Buffer size for bulk-reads */
799  	c->max_bu_buf_len = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ;
800  	if (c->max_bu_buf_len > c->leb_size)
801  		c->max_bu_buf_len = c->leb_size;
802  	return 0;
803  }
804  
805  /**
806   * bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
807   * @c: UBIFS file-system description object
808   * @lnum: LEB the write-buffer was synchronized to
809   * @free: how many free bytes left in this LEB
810   * @pad: how many bytes were padded
811   *
812   * This is a callback function which is called by the I/O unit when the
813   * write-buffer is synchronized. We need this to correctly maintain space
814   * accounting in bud logical eraseblocks. This function returns zero in case of
815   * success and a negative error code in case of failure.
816   *
817   * This function actually belongs to the journal, but we keep it here because
818   * we want to keep it static.
819   */
820  static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
821  {
822  	return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
823  }
824  
825  /*
826   * init_constants_sb - initialize UBIFS constants.
827   * @c: UBIFS file-system description object
828   *
829   * This is a helper function which initializes various UBIFS constants after
830   * the superblock has been read. It also checks various UBIFS parameters and
831   * makes sure they are all right. Returns zero in case of success and a
832   * negative error code in case of failure.
833   */
834  static int init_constants_sb(struct ubifs_info *c)
835  {
836  	int tmp, err;
837  	long long tmp64;
838  
839  	c->main_bytes = (long long)c->main_lebs * c->leb_size;
840  	c->max_znode_sz = sizeof(struct ubifs_znode) +
841  				c->fanout * sizeof(struct ubifs_zbranch);
842  
843  	tmp = ubifs_idx_node_sz(c, 1);
844  	c->ranges[UBIFS_IDX_NODE].min_len = tmp;
845  	c->min_idx_node_sz = ALIGN(tmp, 8);
846  
847  	tmp = ubifs_idx_node_sz(c, c->fanout);
848  	c->ranges[UBIFS_IDX_NODE].max_len = tmp;
849  	c->max_idx_node_sz = ALIGN(tmp, 8);
850  
851  	/* Make sure LEB size is large enough to fit full commit */
852  	tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
853  	tmp = ALIGN(tmp, c->min_io_size);
854  	if (tmp > c->leb_size) {
855  		ubifs_err(c, "too small LEB size %d, at least %d needed",
856  			  c->leb_size, tmp);
857  		return -EINVAL;
858  	}
859  
860  	/*
861  	 * Make sure that the log is large enough to fit reference nodes for
862  	 * all buds plus one reserved LEB.
863  	 */
864  	tmp64 = c->max_bud_bytes + c->leb_size - 1;
865  	c->max_bud_cnt = div_u64(tmp64, c->leb_size);
866  	tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
867  	tmp /= c->leb_size;
868  	tmp += 1;
869  	if (c->log_lebs < tmp) {
870  		ubifs_err(c, "too small log %d LEBs, required min. %d LEBs",
871  			  c->log_lebs, tmp);
872  		return -EINVAL;
873  	}
874  
875  	/*
876  	 * When budgeting we assume worst-case scenarios when the pages are not
877  	 * be compressed and direntries are of the maximum size.
878  	 *
879  	 * Note, data, which may be stored in inodes is budgeted separately, so
880  	 * it is not included into 'c->bi.inode_budget'.
881  	 */
882  	c->bi.page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
883  	c->bi.inode_budget = UBIFS_INO_NODE_SZ;
884  	c->bi.dent_budget = UBIFS_MAX_DENT_NODE_SZ;
885  
886  	/*
887  	 * When the amount of flash space used by buds becomes
888  	 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
889  	 * The writers are unblocked when the commit is finished. To avoid
890  	 * writers to be blocked UBIFS initiates background commit in advance,
891  	 * when number of bud bytes becomes above the limit defined below.
892  	 */
893  	c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
894  
895  	/*
896  	 * Ensure minimum journal size. All the bytes in the journal heads are
897  	 * considered to be used, when calculating the current journal usage.
898  	 * Consequently, if the journal is too small, UBIFS will treat it as
899  	 * always full.
900  	 */
901  	tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1;
902  	if (c->bg_bud_bytes < tmp64)
903  		c->bg_bud_bytes = tmp64;
904  	if (c->max_bud_bytes < tmp64 + c->leb_size)
905  		c->max_bud_bytes = tmp64 + c->leb_size;
906  
907  	err = ubifs_calc_lpt_geom(c);
908  	if (err)
909  		return err;
910  
911  	/* Initialize effective LEB size used in budgeting calculations */
912  	c->idx_leb_size = c->leb_size - c->max_idx_node_sz;
913  	return 0;
914  }
915  
916  /*
917   * init_constants_master - initialize UBIFS constants.
918   * @c: UBIFS file-system description object
919   *
920   * This is a helper function which initializes various UBIFS constants after
921   * the master node has been read. It also checks various UBIFS parameters and
922   * makes sure they are all right.
923   */
924  static void init_constants_master(struct ubifs_info *c)
925  {
926  	long long tmp64;
927  
928  	c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c);
929  	c->report_rp_size = ubifs_reported_space(c, c->rp_size);
930  
931  	/*
932  	 * Calculate total amount of FS blocks. This number is not used
933  	 * internally because it does not make much sense for UBIFS, but it is
934  	 * necessary to report something for the 'statfs()' call.
935  	 *
936  	 * Subtract the LEB reserved for GC, the LEB which is reserved for
937  	 * deletions, minimum LEBs for the index, and assume only one journal
938  	 * head is available.
939  	 */
940  	tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1;
941  	tmp64 *= (long long)c->leb_size - c->leb_overhead;
942  	tmp64 = ubifs_reported_space(c, tmp64);
943  	c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
944  }
945  
946  /**
947   * take_gc_lnum - reserve GC LEB.
948   * @c: UBIFS file-system description object
949   *
950   * This function ensures that the LEB reserved for garbage collection is marked
951   * as "taken" in lprops. We also have to set free space to LEB size and dirty
952   * space to zero, because lprops may contain out-of-date information if the
953   * file-system was un-mounted before it has been committed. This function
954   * returns zero in case of success and a negative error code in case of
955   * failure.
956   */
957  static int take_gc_lnum(struct ubifs_info *c)
958  {
959  	int err;
960  
961  	if (c->gc_lnum == -1) {
962  		ubifs_err(c, "no LEB for GC");
963  		return -EINVAL;
964  	}
965  
966  	/* And we have to tell lprops that this LEB is taken */
967  	err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
968  				  LPROPS_TAKEN, 0, 0);
969  	return err;
970  }
971  
972  /**
973   * alloc_wbufs - allocate write-buffers.
974   * @c: UBIFS file-system description object
975   *
976   * This helper function allocates and initializes UBIFS write-buffers. Returns
977   * zero in case of success and %-ENOMEM in case of failure.
978   */
979  static int alloc_wbufs(struct ubifs_info *c)
980  {
981  	int i, err;
982  
983  	c->jheads = kcalloc(c->jhead_cnt, sizeof(struct ubifs_jhead),
984  			    GFP_KERNEL);
985  	if (!c->jheads)
986  		return -ENOMEM;
987  
988  	/* Initialize journal heads */
989  	for (i = 0; i < c->jhead_cnt; i++) {
990  		INIT_LIST_HEAD(&c->jheads[i].buds_list);
991  		err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
992  		if (err)
993  			return err;
994  
995  		c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
996  		c->jheads[i].wbuf.jhead = i;
997  		c->jheads[i].grouped = 1;
998  	}
999  
1000  	/*
1001  	 * Garbage Collector head does not need to be synchronized by timer.
1002  	 * Also GC head nodes are not grouped.
1003  	 */
1004  	c->jheads[GCHD].wbuf.no_timer = 1;
1005  	c->jheads[GCHD].grouped = 0;
1006  
1007  	return 0;
1008  }
1009  
1010  /**
1011   * free_wbufs - free write-buffers.
1012   * @c: UBIFS file-system description object
1013   */
1014  static void free_wbufs(struct ubifs_info *c)
1015  {
1016  	int i;
1017  
1018  	if (c->jheads) {
1019  		for (i = 0; i < c->jhead_cnt; i++) {
1020  			kfree(c->jheads[i].wbuf.buf);
1021  			kfree(c->jheads[i].wbuf.inodes);
1022  		}
1023  		kfree(c->jheads);
1024  		c->jheads = NULL;
1025  	}
1026  }
1027  
1028  /**
1029   * free_orphans - free orphans.
1030   * @c: UBIFS file-system description object
1031   */
1032  static void free_orphans(struct ubifs_info *c)
1033  {
1034  	struct ubifs_orphan *orph;
1035  
1036  	while (c->orph_dnext) {
1037  		orph = c->orph_dnext;
1038  		c->orph_dnext = orph->dnext;
1039  		list_del(&orph->list);
1040  		kfree(orph);
1041  	}
1042  
1043  	while (!list_empty(&c->orph_list)) {
1044  		orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
1045  		list_del(&orph->list);
1046  		kfree(orph);
1047  		ubifs_err(c, "orphan list not empty at unmount");
1048  	}
1049  
1050  	vfree(c->orph_buf);
1051  	c->orph_buf = NULL;
1052  }
1053  
1054  /**
1055   * free_buds - free per-bud objects.
1056   * @c: UBIFS file-system description object
1057   */
1058  static void free_buds(struct ubifs_info *c)
1059  {
1060  	struct ubifs_bud *bud, *n;
1061  
1062  	rbtree_postorder_for_each_entry_safe(bud, n, &c->buds, rb)
1063  		kfree(bud);
1064  }
1065  
1066  /**
1067   * check_volume_empty - check if the UBI volume is empty.
1068   * @c: UBIFS file-system description object
1069   *
1070   * This function checks if the UBIFS volume is empty by looking if its LEBs are
1071   * mapped or not. The result of checking is stored in the @c->empty variable.
1072   * Returns zero in case of success and a negative error code in case of
1073   * failure.
1074   */
1075  static int check_volume_empty(struct ubifs_info *c)
1076  {
1077  	int lnum, err;
1078  
1079  	c->empty = 1;
1080  	for (lnum = 0; lnum < c->leb_cnt; lnum++) {
1081  		err = ubifs_is_mapped(c, lnum);
1082  		if (unlikely(err < 0))
1083  			return err;
1084  		if (err == 1) {
1085  			c->empty = 0;
1086  			break;
1087  		}
1088  
1089  		cond_resched();
1090  	}
1091  
1092  	return 0;
1093  }
1094  
1095  /*
1096   * UBIFS mount options.
1097   *
1098   * Opt_fast_unmount: do not run a journal commit before un-mounting
1099   * Opt_norm_unmount: run a journal commit before un-mounting
1100   * Opt_bulk_read: enable bulk-reads
1101   * Opt_no_bulk_read: disable bulk-reads
1102   * Opt_chk_data_crc: check CRCs when reading data nodes
1103   * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
1104   * Opt_override_compr: override default compressor
1105   * Opt_err: just end of array marker
1106   */
1107  enum {
1108  	Opt_fast_unmount,
1109  	Opt_norm_unmount,
1110  	Opt_bulk_read,
1111  	Opt_no_bulk_read,
1112  	Opt_chk_data_crc,
1113  	Opt_no_chk_data_crc,
1114  	Opt_override_compr,
1115  	Opt_err,
1116  };
1117  
1118  #ifndef __UBOOT__
1119  static const match_table_t tokens = {
1120  	{Opt_fast_unmount, "fast_unmount"},
1121  	{Opt_norm_unmount, "norm_unmount"},
1122  	{Opt_bulk_read, "bulk_read"},
1123  	{Opt_no_bulk_read, "no_bulk_read"},
1124  	{Opt_chk_data_crc, "chk_data_crc"},
1125  	{Opt_no_chk_data_crc, "no_chk_data_crc"},
1126  	{Opt_override_compr, "compr=%s"},
1127  	{Opt_err, NULL},
1128  };
1129  
1130  /**
1131   * parse_standard_option - parse a standard mount option.
1132   * @option: the option to parse
1133   *
1134   * Normally, standard mount options like "sync" are passed to file-systems as
1135   * flags. However, when a "rootflags=" kernel boot parameter is used, they may
1136   * be present in the options string. This function tries to deal with this
1137   * situation and parse standard options. Returns 0 if the option was not
1138   * recognized, and the corresponding integer flag if it was.
1139   *
1140   * UBIFS is only interested in the "sync" option, so do not check for anything
1141   * else.
1142   */
1143  static int parse_standard_option(const char *option)
1144  {
1145  
1146  	pr_notice("UBIFS: parse %s\n", option);
1147  	if (!strcmp(option, "sync"))
1148  		return MS_SYNCHRONOUS;
1149  	return 0;
1150  }
1151  
1152  /**
1153   * ubifs_parse_options - parse mount parameters.
1154   * @c: UBIFS file-system description object
1155   * @options: parameters to parse
1156   * @is_remount: non-zero if this is FS re-mount
1157   *
1158   * This function parses UBIFS mount options and returns zero in case success
1159   * and a negative error code in case of failure.
1160   */
1161  static int ubifs_parse_options(struct ubifs_info *c, char *options,
1162  			       int is_remount)
1163  {
1164  	char *p;
1165  	substring_t args[MAX_OPT_ARGS];
1166  
1167  	if (!options)
1168  		return 0;
1169  
1170  	while ((p = strsep(&options, ","))) {
1171  		int token;
1172  
1173  		if (!*p)
1174  			continue;
1175  
1176  		token = match_token(p, tokens, args);
1177  		switch (token) {
1178  		/*
1179  		 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored.
1180  		 * We accept them in order to be backward-compatible. But this
1181  		 * should be removed at some point.
1182  		 */
1183  		case Opt_fast_unmount:
1184  			c->mount_opts.unmount_mode = 2;
1185  			break;
1186  		case Opt_norm_unmount:
1187  			c->mount_opts.unmount_mode = 1;
1188  			break;
1189  		case Opt_bulk_read:
1190  			c->mount_opts.bulk_read = 2;
1191  			c->bulk_read = 1;
1192  			break;
1193  		case Opt_no_bulk_read:
1194  			c->mount_opts.bulk_read = 1;
1195  			c->bulk_read = 0;
1196  			break;
1197  		case Opt_chk_data_crc:
1198  			c->mount_opts.chk_data_crc = 2;
1199  			c->no_chk_data_crc = 0;
1200  			break;
1201  		case Opt_no_chk_data_crc:
1202  			c->mount_opts.chk_data_crc = 1;
1203  			c->no_chk_data_crc = 1;
1204  			break;
1205  		case Opt_override_compr:
1206  		{
1207  			char *name = match_strdup(&args[0]);
1208  
1209  			if (!name)
1210  				return -ENOMEM;
1211  			if (!strcmp(name, "none"))
1212  				c->mount_opts.compr_type = UBIFS_COMPR_NONE;
1213  			else if (!strcmp(name, "lzo"))
1214  				c->mount_opts.compr_type = UBIFS_COMPR_LZO;
1215  			else if (!strcmp(name, "zlib"))
1216  				c->mount_opts.compr_type = UBIFS_COMPR_ZLIB;
1217  			else {
1218  				ubifs_err(c, "unknown compressor \"%s\"", name); //FIXME: is c ready?
1219  				kfree(name);
1220  				return -EINVAL;
1221  			}
1222  			kfree(name);
1223  			c->mount_opts.override_compr = 1;
1224  			c->default_compr = c->mount_opts.compr_type;
1225  			break;
1226  		}
1227  		default:
1228  		{
1229  			unsigned long flag;
1230  			struct super_block *sb = c->vfs_sb;
1231  
1232  			flag = parse_standard_option(p);
1233  			if (!flag) {
1234  				ubifs_err(c, "unrecognized mount option \"%s\" or missing value",
1235  					  p);
1236  				return -EINVAL;
1237  			}
1238  			sb->s_flags |= flag;
1239  			break;
1240  		}
1241  		}
1242  	}
1243  
1244  	return 0;
1245  }
1246  #endif
1247  
1248  /**
1249   * destroy_journal - destroy journal data structures.
1250   * @c: UBIFS file-system description object
1251   *
1252   * This function destroys journal data structures including those that may have
1253   * been created by recovery functions.
1254   */
1255  static void destroy_journal(struct ubifs_info *c)
1256  {
1257  	while (!list_empty(&c->unclean_leb_list)) {
1258  		struct ubifs_unclean_leb *ucleb;
1259  
1260  		ucleb = list_entry(c->unclean_leb_list.next,
1261  				   struct ubifs_unclean_leb, list);
1262  		list_del(&ucleb->list);
1263  		kfree(ucleb);
1264  	}
1265  	while (!list_empty(&c->old_buds)) {
1266  		struct ubifs_bud *bud;
1267  
1268  		bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
1269  		list_del(&bud->list);
1270  		kfree(bud);
1271  	}
1272  	ubifs_destroy_idx_gc(c);
1273  	ubifs_destroy_size_tree(c);
1274  	ubifs_tnc_close(c);
1275  	free_buds(c);
1276  }
1277  
1278  /**
1279   * bu_init - initialize bulk-read information.
1280   * @c: UBIFS file-system description object
1281   */
1282  static void bu_init(struct ubifs_info *c)
1283  {
1284  	ubifs_assert(c->bulk_read == 1);
1285  
1286  	if (c->bu.buf)
1287  		return; /* Already initialized */
1288  
1289  again:
1290  	c->bu.buf = kmalloc(c->max_bu_buf_len, GFP_KERNEL | __GFP_NOWARN);
1291  	if (!c->bu.buf) {
1292  		if (c->max_bu_buf_len > UBIFS_KMALLOC_OK) {
1293  			c->max_bu_buf_len = UBIFS_KMALLOC_OK;
1294  			goto again;
1295  		}
1296  
1297  		/* Just disable bulk-read */
1298  		ubifs_warn(c, "cannot allocate %d bytes of memory for bulk-read, disabling it",
1299  			   c->max_bu_buf_len);
1300  		c->mount_opts.bulk_read = 1;
1301  		c->bulk_read = 0;
1302  		return;
1303  	}
1304  }
1305  
1306  #ifndef __UBOOT__
1307  /**
1308   * check_free_space - check if there is enough free space to mount.
1309   * @c: UBIFS file-system description object
1310   *
1311   * This function makes sure UBIFS has enough free space to be mounted in
1312   * read/write mode. UBIFS must always have some free space to allow deletions.
1313   */
1314  static int check_free_space(struct ubifs_info *c)
1315  {
1316  	ubifs_assert(c->dark_wm > 0);
1317  	if (c->lst.total_free + c->lst.total_dirty < c->dark_wm) {
1318  		ubifs_err(c, "insufficient free space to mount in R/W mode");
1319  		ubifs_dump_budg(c, &c->bi);
1320  		ubifs_dump_lprops(c);
1321  		return -ENOSPC;
1322  	}
1323  	return 0;
1324  }
1325  #endif
1326  
1327  /**
1328   * mount_ubifs - mount UBIFS file-system.
1329   * @c: UBIFS file-system description object
1330   *
1331   * This function mounts UBIFS file system. Returns zero in case of success and
1332   * a negative error code in case of failure.
1333   */
1334  static int mount_ubifs(struct ubifs_info *c)
1335  {
1336  	int err;
1337  	long long x, y;
1338  	size_t sz;
1339  
1340  	c->ro_mount = !!(c->vfs_sb->s_flags & MS_RDONLY);
1341  	/* Suppress error messages while probing if MS_SILENT is set */
1342  	c->probing = !!(c->vfs_sb->s_flags & MS_SILENT);
1343  #ifdef __UBOOT__
1344  	if (!c->ro_mount) {
1345  		printf("UBIFS: only ro mode in U-Boot allowed.\n");
1346  		return -EACCES;
1347  	}
1348  #endif
1349  
1350  	err = init_constants_early(c);
1351  	if (err)
1352  		return err;
1353  
1354  	err = ubifs_debugging_init(c);
1355  	if (err)
1356  		return err;
1357  
1358  	err = check_volume_empty(c);
1359  	if (err)
1360  		goto out_free;
1361  
1362  	if (c->empty && (c->ro_mount || c->ro_media)) {
1363  		/*
1364  		 * This UBI volume is empty, and read-only, or the file system
1365  		 * is mounted read-only - we cannot format it.
1366  		 */
1367  		ubifs_err(c, "can't format empty UBI volume: read-only %s",
1368  			  c->ro_media ? "UBI volume" : "mount");
1369  		err = -EROFS;
1370  		goto out_free;
1371  	}
1372  
1373  	if (c->ro_media && !c->ro_mount) {
1374  		ubifs_err(c, "cannot mount read-write - read-only media");
1375  		err = -EROFS;
1376  		goto out_free;
1377  	}
1378  
1379  	/*
1380  	 * The requirement for the buffer is that it should fit indexing B-tree
1381  	 * height amount of integers. We assume the height if the TNC tree will
1382  	 * never exceed 64.
1383  	 */
1384  	err = -ENOMEM;
1385  	c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
1386  	if (!c->bottom_up_buf)
1387  		goto out_free;
1388  
1389  	c->sbuf = vmalloc(c->leb_size);
1390  	if (!c->sbuf)
1391  		goto out_free;
1392  
1393  #ifndef __UBOOT__
1394  	if (!c->ro_mount) {
1395  		c->ileb_buf = vmalloc(c->leb_size);
1396  		if (!c->ileb_buf)
1397  			goto out_free;
1398  	}
1399  #endif
1400  
1401  	if (c->bulk_read == 1)
1402  		bu_init(c);
1403  
1404  #ifndef __UBOOT__
1405  	if (!c->ro_mount) {
1406  		c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ,
1407  					       GFP_KERNEL);
1408  		if (!c->write_reserve_buf)
1409  			goto out_free;
1410  	}
1411  #endif
1412  
1413  	c->mounting = 1;
1414  
1415  	err = ubifs_read_superblock(c);
1416  	if (err)
1417  		goto out_free;
1418  
1419  	c->probing = 0;
1420  
1421  	/*
1422  	 * Make sure the compressor which is set as default in the superblock
1423  	 * or overridden by mount options is actually compiled in.
1424  	 */
1425  	if (!ubifs_compr_present(c->default_compr)) {
1426  		ubifs_err(c, "'compressor \"%s\" is not compiled in",
1427  			  ubifs_compr_name(c->default_compr));
1428  		err = -ENOTSUPP;
1429  		goto out_free;
1430  	}
1431  
1432  	err = init_constants_sb(c);
1433  	if (err)
1434  		goto out_free;
1435  
1436  	sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
1437  	sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
1438  	c->cbuf = kmalloc(sz, GFP_NOFS);
1439  	if (!c->cbuf) {
1440  		err = -ENOMEM;
1441  		goto out_free;
1442  	}
1443  
1444  	err = alloc_wbufs(c);
1445  	if (err)
1446  		goto out_cbuf;
1447  
1448  	sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
1449  #ifndef __UBOOT__
1450  	if (!c->ro_mount) {
1451  		/* Create background thread */
1452  		c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
1453  		if (IS_ERR(c->bgt)) {
1454  			err = PTR_ERR(c->bgt);
1455  			c->bgt = NULL;
1456  			ubifs_err(c, "cannot spawn \"%s\", error %d",
1457  				  c->bgt_name, err);
1458  			goto out_wbufs;
1459  		}
1460  		wake_up_process(c->bgt);
1461  	}
1462  #endif
1463  
1464  	err = ubifs_read_master(c);
1465  	if (err)
1466  		goto out_master;
1467  
1468  	init_constants_master(c);
1469  
1470  	if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
1471  		ubifs_msg(c, "recovery needed");
1472  		c->need_recovery = 1;
1473  	}
1474  
1475  #ifndef __UBOOT__
1476  	if (c->need_recovery && !c->ro_mount) {
1477  		err = ubifs_recover_inl_heads(c, c->sbuf);
1478  		if (err)
1479  			goto out_master;
1480  	}
1481  #endif
1482  
1483  	err = ubifs_lpt_init(c, 1, !c->ro_mount);
1484  	if (err)
1485  		goto out_master;
1486  
1487  #ifndef __UBOOT__
1488  	if (!c->ro_mount && c->space_fixup) {
1489  		err = ubifs_fixup_free_space(c);
1490  		if (err)
1491  			goto out_lpt;
1492  	}
1493  
1494  	if (!c->ro_mount && !c->need_recovery) {
1495  		/*
1496  		 * Set the "dirty" flag so that if we reboot uncleanly we
1497  		 * will notice this immediately on the next mount.
1498  		 */
1499  		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1500  		err = ubifs_write_master(c);
1501  		if (err)
1502  			goto out_lpt;
1503  	}
1504  #endif
1505  
1506  	err = dbg_check_idx_size(c, c->bi.old_idx_sz);
1507  	if (err)
1508  		goto out_lpt;
1509  
1510  	err = ubifs_replay_journal(c);
1511  	if (err)
1512  		goto out_journal;
1513  
1514  	/* Calculate 'min_idx_lebs' after journal replay */
1515  	c->bi.min_idx_lebs = ubifs_calc_min_idx_lebs(c);
1516  
1517  	err = ubifs_mount_orphans(c, c->need_recovery, c->ro_mount);
1518  	if (err)
1519  		goto out_orphans;
1520  
1521  	if (!c->ro_mount) {
1522  #ifndef __UBOOT__
1523  		int lnum;
1524  
1525  		err = check_free_space(c);
1526  		if (err)
1527  			goto out_orphans;
1528  
1529  		/* Check for enough log space */
1530  		lnum = c->lhead_lnum + 1;
1531  		if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1532  			lnum = UBIFS_LOG_LNUM;
1533  		if (lnum == c->ltail_lnum) {
1534  			err = ubifs_consolidate_log(c);
1535  			if (err)
1536  				goto out_orphans;
1537  		}
1538  
1539  		if (c->need_recovery) {
1540  			err = ubifs_recover_size(c);
1541  			if (err)
1542  				goto out_orphans;
1543  			err = ubifs_rcvry_gc_commit(c);
1544  			if (err)
1545  				goto out_orphans;
1546  		} else {
1547  			err = take_gc_lnum(c);
1548  			if (err)
1549  				goto out_orphans;
1550  
1551  			/*
1552  			 * GC LEB may contain garbage if there was an unclean
1553  			 * reboot, and it should be un-mapped.
1554  			 */
1555  			err = ubifs_leb_unmap(c, c->gc_lnum);
1556  			if (err)
1557  				goto out_orphans;
1558  		}
1559  
1560  		err = dbg_check_lprops(c);
1561  		if (err)
1562  			goto out_orphans;
1563  #endif
1564  	} else if (c->need_recovery) {
1565  		err = ubifs_recover_size(c);
1566  		if (err)
1567  			goto out_orphans;
1568  	} else {
1569  		/*
1570  		 * Even if we mount read-only, we have to set space in GC LEB
1571  		 * to proper value because this affects UBIFS free space
1572  		 * reporting. We do not want to have a situation when
1573  		 * re-mounting from R/O to R/W changes amount of free space.
1574  		 */
1575  		err = take_gc_lnum(c);
1576  		if (err)
1577  			goto out_orphans;
1578  	}
1579  
1580  #ifndef __UBOOT__
1581  	spin_lock(&ubifs_infos_lock);
1582  	list_add_tail(&c->infos_list, &ubifs_infos);
1583  	spin_unlock(&ubifs_infos_lock);
1584  #endif
1585  
1586  	if (c->need_recovery) {
1587  		if (c->ro_mount)
1588  			ubifs_msg(c, "recovery deferred");
1589  		else {
1590  			c->need_recovery = 0;
1591  			ubifs_msg(c, "recovery completed");
1592  			/*
1593  			 * GC LEB has to be empty and taken at this point. But
1594  			 * the journal head LEBs may also be accounted as
1595  			 * "empty taken" if they are empty.
1596  			 */
1597  			ubifs_assert(c->lst.taken_empty_lebs > 0);
1598  		}
1599  	} else
1600  		ubifs_assert(c->lst.taken_empty_lebs > 0);
1601  
1602  	err = dbg_check_filesystem(c);
1603  	if (err)
1604  		goto out_infos;
1605  
1606  	err = dbg_debugfs_init_fs(c);
1607  	if (err)
1608  		goto out_infos;
1609  
1610  	c->mounting = 0;
1611  
1612  	ubifs_msg(c, "UBIFS: mounted UBI device %d, volume %d, name \"%s\"%s",
1613  		  c->vi.ubi_num, c->vi.vol_id, c->vi.name,
1614  		  c->ro_mount ? ", R/O mode" : "");
1615  	x = (long long)c->main_lebs * c->leb_size;
1616  	y = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
1617  	ubifs_msg(c, "LEB size: %d bytes (%d KiB), min./max. I/O unit sizes: %d bytes/%d bytes",
1618  		  c->leb_size, c->leb_size >> 10, c->min_io_size,
1619  		  c->max_write_size);
1620  	ubifs_msg(c, "FS size: %lld bytes (%lld MiB, %d LEBs), journal size %lld bytes (%lld MiB, %d LEBs)",
1621  		  x, x >> 20, c->main_lebs,
1622  		  y, y >> 20, c->log_lebs + c->max_bud_cnt);
1623  	ubifs_msg(c, "reserved for root: %llu bytes (%llu KiB)",
1624  		  c->report_rp_size, c->report_rp_size >> 10);
1625  	ubifs_msg(c, "media format: w%d/r%d (latest is w%d/r%d), UUID %pUB%s",
1626  		  c->fmt_version, c->ro_compat_version,
1627  		  UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION, c->uuid,
1628  		  c->big_lpt ? ", big LPT model" : ", small LPT model");
1629  
1630  	dbg_gen("default compressor:  %s", ubifs_compr_name(c->default_compr));
1631  	dbg_gen("data journal heads:  %d",
1632  		c->jhead_cnt - NONDATA_JHEADS_CNT);
1633  	dbg_gen("log LEBs:            %d (%d - %d)",
1634  		c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
1635  	dbg_gen("LPT area LEBs:       %d (%d - %d)",
1636  		c->lpt_lebs, c->lpt_first, c->lpt_last);
1637  	dbg_gen("orphan area LEBs:    %d (%d - %d)",
1638  		c->orph_lebs, c->orph_first, c->orph_last);
1639  	dbg_gen("main area LEBs:      %d (%d - %d)",
1640  		c->main_lebs, c->main_first, c->leb_cnt - 1);
1641  	dbg_gen("index LEBs:          %d", c->lst.idx_lebs);
1642  	dbg_gen("total index bytes:   %lld (%lld KiB, %lld MiB)",
1643  		c->bi.old_idx_sz, c->bi.old_idx_sz >> 10,
1644  		c->bi.old_idx_sz >> 20);
1645  	dbg_gen("key hash type:       %d", c->key_hash_type);
1646  	dbg_gen("tree fanout:         %d", c->fanout);
1647  	dbg_gen("reserved GC LEB:     %d", c->gc_lnum);
1648  	dbg_gen("max. znode size      %d", c->max_znode_sz);
1649  	dbg_gen("max. index node size %d", c->max_idx_node_sz);
1650  	dbg_gen("node sizes:          data %zu, inode %zu, dentry %zu",
1651  		UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ);
1652  	dbg_gen("node sizes:          trun %zu, sb %zu, master %zu",
1653  		UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ);
1654  	dbg_gen("node sizes:          ref %zu, cmt. start %zu, orph %zu",
1655  		UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ);
1656  	dbg_gen("max. node sizes:     data %zu, inode %zu dentry %zu, idx %d",
1657  		UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ,
1658  		UBIFS_MAX_DENT_NODE_SZ, ubifs_idx_node_sz(c, c->fanout));
1659  	dbg_gen("dead watermark:      %d", c->dead_wm);
1660  	dbg_gen("dark watermark:      %d", c->dark_wm);
1661  	dbg_gen("LEB overhead:        %d", c->leb_overhead);
1662  	x = (long long)c->main_lebs * c->dark_wm;
1663  	dbg_gen("max. dark space:     %lld (%lld KiB, %lld MiB)",
1664  		x, x >> 10, x >> 20);
1665  	dbg_gen("maximum bud bytes:   %lld (%lld KiB, %lld MiB)",
1666  		c->max_bud_bytes, c->max_bud_bytes >> 10,
1667  		c->max_bud_bytes >> 20);
1668  	dbg_gen("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
1669  		c->bg_bud_bytes, c->bg_bud_bytes >> 10,
1670  		c->bg_bud_bytes >> 20);
1671  	dbg_gen("current bud bytes    %lld (%lld KiB, %lld MiB)",
1672  		c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
1673  	dbg_gen("max. seq. number:    %llu", c->max_sqnum);
1674  	dbg_gen("commit number:       %llu", c->cmt_no);
1675  
1676  	return 0;
1677  
1678  out_infos:
1679  	spin_lock(&ubifs_infos_lock);
1680  	list_del(&c->infos_list);
1681  	spin_unlock(&ubifs_infos_lock);
1682  out_orphans:
1683  	free_orphans(c);
1684  out_journal:
1685  	destroy_journal(c);
1686  out_lpt:
1687  	ubifs_lpt_free(c, 0);
1688  out_master:
1689  	kfree(c->mst_node);
1690  	kfree(c->rcvrd_mst_node);
1691  	if (c->bgt)
1692  		kthread_stop(c->bgt);
1693  #ifndef __UBOOT__
1694  out_wbufs:
1695  #endif
1696  	free_wbufs(c);
1697  out_cbuf:
1698  	kfree(c->cbuf);
1699  out_free:
1700  	kfree(c->write_reserve_buf);
1701  	kfree(c->bu.buf);
1702  	vfree(c->ileb_buf);
1703  	vfree(c->sbuf);
1704  	kfree(c->bottom_up_buf);
1705  	ubifs_debugging_exit(c);
1706  	return err;
1707  }
1708  
1709  /**
1710   * ubifs_umount - un-mount UBIFS file-system.
1711   * @c: UBIFS file-system description object
1712   *
1713   * Note, this function is called to free allocated resourced when un-mounting,
1714   * as well as free resources when an error occurred while we were half way
1715   * through mounting (error path cleanup function). So it has to make sure the
1716   * resource was actually allocated before freeing it.
1717   */
1718  #ifndef __UBOOT__
1719  static void ubifs_umount(struct ubifs_info *c)
1720  #else
1721  void ubifs_umount(struct ubifs_info *c)
1722  #endif
1723  {
1724  	dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
1725  		c->vi.vol_id);
1726  
1727  	dbg_debugfs_exit_fs(c);
1728  	spin_lock(&ubifs_infos_lock);
1729  	list_del(&c->infos_list);
1730  	spin_unlock(&ubifs_infos_lock);
1731  
1732  #ifndef __UBOOT__
1733  	if (c->bgt)
1734  		kthread_stop(c->bgt);
1735  
1736  	destroy_journal(c);
1737  #endif
1738  	free_wbufs(c);
1739  	free_orphans(c);
1740  	ubifs_lpt_free(c, 0);
1741  
1742  	kfree(c->cbuf);
1743  	kfree(c->rcvrd_mst_node);
1744  	kfree(c->mst_node);
1745  	kfree(c->write_reserve_buf);
1746  	kfree(c->bu.buf);
1747  	vfree(c->ileb_buf);
1748  	vfree(c->sbuf);
1749  	kfree(c->bottom_up_buf);
1750  	ubifs_debugging_exit(c);
1751  #ifdef __UBOOT__
1752  	/* Finally free U-Boot's global copy of superblock */
1753  	if (ubifs_sb != NULL) {
1754  		free(ubifs_sb->s_fs_info);
1755  		free(ubifs_sb);
1756  	}
1757  #endif
1758  }
1759  
1760  #ifndef __UBOOT__
1761  /**
1762   * ubifs_remount_rw - re-mount in read-write mode.
1763   * @c: UBIFS file-system description object
1764   *
1765   * UBIFS avoids allocating many unnecessary resources when mounted in read-only
1766   * mode. This function allocates the needed resources and re-mounts UBIFS in
1767   * read-write mode.
1768   */
1769  static int ubifs_remount_rw(struct ubifs_info *c)
1770  {
1771  	int err, lnum;
1772  
1773  	if (c->rw_incompat) {
1774  		ubifs_err(c, "the file-system is not R/W-compatible");
1775  		ubifs_msg(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d",
1776  			  c->fmt_version, c->ro_compat_version,
1777  			  UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION);
1778  		return -EROFS;
1779  	}
1780  
1781  	mutex_lock(&c->umount_mutex);
1782  	dbg_save_space_info(c);
1783  	c->remounting_rw = 1;
1784  	c->ro_mount = 0;
1785  
1786  	if (c->space_fixup) {
1787  		err = ubifs_fixup_free_space(c);
1788  		if (err)
1789  			goto out;
1790  	}
1791  
1792  	err = check_free_space(c);
1793  	if (err)
1794  		goto out;
1795  
1796  	if (c->old_leb_cnt != c->leb_cnt) {
1797  		struct ubifs_sb_node *sup;
1798  
1799  		sup = ubifs_read_sb_node(c);
1800  		if (IS_ERR(sup)) {
1801  			err = PTR_ERR(sup);
1802  			goto out;
1803  		}
1804  		sup->leb_cnt = cpu_to_le32(c->leb_cnt);
1805  		err = ubifs_write_sb_node(c, sup);
1806  		kfree(sup);
1807  		if (err)
1808  			goto out;
1809  	}
1810  
1811  	if (c->need_recovery) {
1812  		ubifs_msg(c, "completing deferred recovery");
1813  		err = ubifs_write_rcvrd_mst_node(c);
1814  		if (err)
1815  			goto out;
1816  		err = ubifs_recover_size(c);
1817  		if (err)
1818  			goto out;
1819  		err = ubifs_clean_lebs(c, c->sbuf);
1820  		if (err)
1821  			goto out;
1822  		err = ubifs_recover_inl_heads(c, c->sbuf);
1823  		if (err)
1824  			goto out;
1825  	} else {
1826  		/* A readonly mount is not allowed to have orphans */
1827  		ubifs_assert(c->tot_orphans == 0);
1828  		err = ubifs_clear_orphans(c);
1829  		if (err)
1830  			goto out;
1831  	}
1832  
1833  	if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
1834  		c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1835  		err = ubifs_write_master(c);
1836  		if (err)
1837  			goto out;
1838  	}
1839  
1840  	c->ileb_buf = vmalloc(c->leb_size);
1841  	if (!c->ileb_buf) {
1842  		err = -ENOMEM;
1843  		goto out;
1844  	}
1845  
1846  	c->write_reserve_buf = kmalloc(COMPRESSED_DATA_NODE_BUF_SZ, GFP_KERNEL);
1847  	if (!c->write_reserve_buf) {
1848  		err = -ENOMEM;
1849  		goto out;
1850  	}
1851  
1852  	err = ubifs_lpt_init(c, 0, 1);
1853  	if (err)
1854  		goto out;
1855  
1856  	/* Create background thread */
1857  	c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
1858  	if (IS_ERR(c->bgt)) {
1859  		err = PTR_ERR(c->bgt);
1860  		c->bgt = NULL;
1861  		ubifs_err(c, "cannot spawn \"%s\", error %d",
1862  			  c->bgt_name, err);
1863  		goto out;
1864  	}
1865  	wake_up_process(c->bgt);
1866  
1867  	c->orph_buf = vmalloc(c->leb_size);
1868  	if (!c->orph_buf) {
1869  		err = -ENOMEM;
1870  		goto out;
1871  	}
1872  
1873  	/* Check for enough log space */
1874  	lnum = c->lhead_lnum + 1;
1875  	if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1876  		lnum = UBIFS_LOG_LNUM;
1877  	if (lnum == c->ltail_lnum) {
1878  		err = ubifs_consolidate_log(c);
1879  		if (err)
1880  			goto out;
1881  	}
1882  
1883  	if (c->need_recovery)
1884  		err = ubifs_rcvry_gc_commit(c);
1885  	else
1886  		err = ubifs_leb_unmap(c, c->gc_lnum);
1887  	if (err)
1888  		goto out;
1889  
1890  	dbg_gen("re-mounted read-write");
1891  	c->remounting_rw = 0;
1892  
1893  	if (c->need_recovery) {
1894  		c->need_recovery = 0;
1895  		ubifs_msg(c, "deferred recovery completed");
1896  	} else {
1897  		/*
1898  		 * Do not run the debugging space check if the were doing
1899  		 * recovery, because when we saved the information we had the
1900  		 * file-system in a state where the TNC and lprops has been
1901  		 * modified in memory, but all the I/O operations (including a
1902  		 * commit) were deferred. So the file-system was in
1903  		 * "non-committed" state. Now the file-system is in committed
1904  		 * state, and of course the amount of free space will change
1905  		 * because, for example, the old index size was imprecise.
1906  		 */
1907  		err = dbg_check_space_info(c);
1908  	}
1909  
1910  	mutex_unlock(&c->umount_mutex);
1911  	return err;
1912  
1913  out:
1914  	c->ro_mount = 1;
1915  	vfree(c->orph_buf);
1916  	c->orph_buf = NULL;
1917  	if (c->bgt) {
1918  		kthread_stop(c->bgt);
1919  		c->bgt = NULL;
1920  	}
1921  	free_wbufs(c);
1922  	kfree(c->write_reserve_buf);
1923  	c->write_reserve_buf = NULL;
1924  	vfree(c->ileb_buf);
1925  	c->ileb_buf = NULL;
1926  	ubifs_lpt_free(c, 1);
1927  	c->remounting_rw = 0;
1928  	mutex_unlock(&c->umount_mutex);
1929  	return err;
1930  }
1931  
1932  /**
1933   * ubifs_remount_ro - re-mount in read-only mode.
1934   * @c: UBIFS file-system description object
1935   *
1936   * We assume VFS has stopped writing. Possibly the background thread could be
1937   * running a commit, however kthread_stop will wait in that case.
1938   */
1939  static void ubifs_remount_ro(struct ubifs_info *c)
1940  {
1941  	int i, err;
1942  
1943  	ubifs_assert(!c->need_recovery);
1944  	ubifs_assert(!c->ro_mount);
1945  
1946  	mutex_lock(&c->umount_mutex);
1947  	if (c->bgt) {
1948  		kthread_stop(c->bgt);
1949  		c->bgt = NULL;
1950  	}
1951  
1952  	dbg_save_space_info(c);
1953  
1954  	for (i = 0; i < c->jhead_cnt; i++)
1955  		ubifs_wbuf_sync(&c->jheads[i].wbuf);
1956  
1957  	c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
1958  	c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
1959  	c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
1960  	err = ubifs_write_master(c);
1961  	if (err)
1962  		ubifs_ro_mode(c, err);
1963  
1964  	vfree(c->orph_buf);
1965  	c->orph_buf = NULL;
1966  	kfree(c->write_reserve_buf);
1967  	c->write_reserve_buf = NULL;
1968  	vfree(c->ileb_buf);
1969  	c->ileb_buf = NULL;
1970  	ubifs_lpt_free(c, 1);
1971  	c->ro_mount = 1;
1972  	err = dbg_check_space_info(c);
1973  	if (err)
1974  		ubifs_ro_mode(c, err);
1975  	mutex_unlock(&c->umount_mutex);
1976  }
1977  
1978  static void ubifs_put_super(struct super_block *sb)
1979  {
1980  	int i;
1981  	struct ubifs_info *c = sb->s_fs_info;
1982  
1983  	ubifs_msg(c, "un-mount UBI device %d", c->vi.ubi_num);
1984  
1985  	/*
1986  	 * The following asserts are only valid if there has not been a failure
1987  	 * of the media. For example, there will be dirty inodes if we failed
1988  	 * to write them back because of I/O errors.
1989  	 */
1990  	if (!c->ro_error) {
1991  		ubifs_assert(c->bi.idx_growth == 0);
1992  		ubifs_assert(c->bi.dd_growth == 0);
1993  		ubifs_assert(c->bi.data_growth == 0);
1994  	}
1995  
1996  	/*
1997  	 * The 'c->umount_lock' prevents races between UBIFS memory shrinker
1998  	 * and file system un-mount. Namely, it prevents the shrinker from
1999  	 * picking this superblock for shrinking - it will be just skipped if
2000  	 * the mutex is locked.
2001  	 */
2002  	mutex_lock(&c->umount_mutex);
2003  	if (!c->ro_mount) {
2004  		/*
2005  		 * First of all kill the background thread to make sure it does
2006  		 * not interfere with un-mounting and freeing resources.
2007  		 */
2008  		if (c->bgt) {
2009  			kthread_stop(c->bgt);
2010  			c->bgt = NULL;
2011  		}
2012  
2013  		/*
2014  		 * On fatal errors c->ro_error is set to 1, in which case we do
2015  		 * not write the master node.
2016  		 */
2017  		if (!c->ro_error) {
2018  			int err;
2019  
2020  			/* Synchronize write-buffers */
2021  			for (i = 0; i < c->jhead_cnt; i++)
2022  				ubifs_wbuf_sync(&c->jheads[i].wbuf);
2023  
2024  			/*
2025  			 * We are being cleanly unmounted which means the
2026  			 * orphans were killed - indicate this in the master
2027  			 * node. Also save the reserved GC LEB number.
2028  			 */
2029  			c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
2030  			c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
2031  			c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
2032  			err = ubifs_write_master(c);
2033  			if (err)
2034  				/*
2035  				 * Recovery will attempt to fix the master area
2036  				 * next mount, so we just print a message and
2037  				 * continue to unmount normally.
2038  				 */
2039  				ubifs_err(c, "failed to write master node, error %d",
2040  					  err);
2041  		} else {
2042  #ifndef __UBOOT__
2043  			for (i = 0; i < c->jhead_cnt; i++)
2044  				/* Make sure write-buffer timers are canceled */
2045  				hrtimer_cancel(&c->jheads[i].wbuf.timer);
2046  #endif
2047  		}
2048  	}
2049  
2050  	ubifs_umount(c);
2051  #ifndef __UBOOT__
2052  	bdi_destroy(&c->bdi);
2053  #endif
2054  	ubi_close_volume(c->ubi);
2055  	mutex_unlock(&c->umount_mutex);
2056  }
2057  #endif
2058  
2059  #ifndef __UBOOT__
2060  static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
2061  {
2062  	int err;
2063  	struct ubifs_info *c = sb->s_fs_info;
2064  
2065  	sync_filesystem(sb);
2066  	dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
2067  
2068  	err = ubifs_parse_options(c, data, 1);
2069  	if (err) {
2070  		ubifs_err(c, "invalid or unknown remount parameter");
2071  		return err;
2072  	}
2073  
2074  	if (c->ro_mount && !(*flags & MS_RDONLY)) {
2075  		if (c->ro_error) {
2076  			ubifs_msg(c, "cannot re-mount R/W due to prior errors");
2077  			return -EROFS;
2078  		}
2079  		if (c->ro_media) {
2080  			ubifs_msg(c, "cannot re-mount R/W - UBI volume is R/O");
2081  			return -EROFS;
2082  		}
2083  		err = ubifs_remount_rw(c);
2084  		if (err)
2085  			return err;
2086  	} else if (!c->ro_mount && (*flags & MS_RDONLY)) {
2087  		if (c->ro_error) {
2088  			ubifs_msg(c, "cannot re-mount R/O due to prior errors");
2089  			return -EROFS;
2090  		}
2091  		ubifs_remount_ro(c);
2092  	}
2093  
2094  	if (c->bulk_read == 1)
2095  		bu_init(c);
2096  	else {
2097  		dbg_gen("disable bulk-read");
2098  		kfree(c->bu.buf);
2099  		c->bu.buf = NULL;
2100  	}
2101  
2102  	ubifs_assert(c->lst.taken_empty_lebs > 0);
2103  	return 0;
2104  }
2105  #endif
2106  
2107  const struct super_operations ubifs_super_operations = {
2108  	.alloc_inode   = ubifs_alloc_inode,
2109  #ifndef __UBOOT__
2110  	.destroy_inode = ubifs_destroy_inode,
2111  	.put_super     = ubifs_put_super,
2112  	.write_inode   = ubifs_write_inode,
2113  	.evict_inode   = ubifs_evict_inode,
2114  	.statfs        = ubifs_statfs,
2115  #endif
2116  	.dirty_inode   = ubifs_dirty_inode,
2117  #ifndef __UBOOT__
2118  	.remount_fs    = ubifs_remount_fs,
2119  	.show_options  = ubifs_show_options,
2120  	.sync_fs       = ubifs_sync_fs,
2121  #endif
2122  };
2123  
2124  /**
2125   * open_ubi - parse UBI device name string and open the UBI device.
2126   * @name: UBI volume name
2127   * @mode: UBI volume open mode
2128   *
2129   * The primary method of mounting UBIFS is by specifying the UBI volume
2130   * character device node path. However, UBIFS may also be mounted withoug any
2131   * character device node using one of the following methods:
2132   *
2133   * o ubiX_Y    - mount UBI device number X, volume Y;
2134   * o ubiY      - mount UBI device number 0, volume Y;
2135   * o ubiX:NAME - mount UBI device X, volume with name NAME;
2136   * o ubi:NAME  - mount UBI device 0, volume with name NAME.
2137   *
2138   * Alternative '!' separator may be used instead of ':' (because some shells
2139   * like busybox may interpret ':' as an NFS host name separator). This function
2140   * returns UBI volume description object in case of success and a negative
2141   * error code in case of failure.
2142   */
2143  static struct ubi_volume_desc *open_ubi(const char *name, int mode)
2144  {
2145  #ifndef __UBOOT__
2146  	struct ubi_volume_desc *ubi;
2147  #endif
2148  	int dev, vol;
2149  	char *endptr;
2150  
2151  #ifndef __UBOOT__
2152  	/* First, try to open using the device node path method */
2153  	ubi = ubi_open_volume_path(name, mode);
2154  	if (!IS_ERR(ubi))
2155  		return ubi;
2156  #endif
2157  
2158  	/* Try the "nodev" method */
2159  	if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
2160  		return ERR_PTR(-EINVAL);
2161  
2162  	/* ubi:NAME method */
2163  	if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
2164  		return ubi_open_volume_nm(0, name + 4, mode);
2165  
2166  	if (!isdigit(name[3]))
2167  		return ERR_PTR(-EINVAL);
2168  
2169  	dev = simple_strtoul(name + 3, &endptr, 0);
2170  
2171  	/* ubiY method */
2172  	if (*endptr == '\0')
2173  		return ubi_open_volume(0, dev, mode);
2174  
2175  	/* ubiX_Y method */
2176  	if (*endptr == '_' && isdigit(endptr[1])) {
2177  		vol = simple_strtoul(endptr + 1, &endptr, 0);
2178  		if (*endptr != '\0')
2179  			return ERR_PTR(-EINVAL);
2180  		return ubi_open_volume(dev, vol, mode);
2181  	}
2182  
2183  	/* ubiX:NAME method */
2184  	if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
2185  		return ubi_open_volume_nm(dev, ++endptr, mode);
2186  
2187  	return ERR_PTR(-EINVAL);
2188  }
2189  
2190  static struct ubifs_info *alloc_ubifs_info(struct ubi_volume_desc *ubi)
2191  {
2192  	struct ubifs_info *c;
2193  
2194  	c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
2195  	if (c) {
2196  		spin_lock_init(&c->cnt_lock);
2197  		spin_lock_init(&c->cs_lock);
2198  		spin_lock_init(&c->buds_lock);
2199  		spin_lock_init(&c->space_lock);
2200  		spin_lock_init(&c->orphan_lock);
2201  		init_rwsem(&c->commit_sem);
2202  		mutex_init(&c->lp_mutex);
2203  		mutex_init(&c->tnc_mutex);
2204  		mutex_init(&c->log_mutex);
2205  		mutex_init(&c->umount_mutex);
2206  		mutex_init(&c->bu_mutex);
2207  		mutex_init(&c->write_reserve_mutex);
2208  		init_waitqueue_head(&c->cmt_wq);
2209  		c->buds = RB_ROOT;
2210  		c->old_idx = RB_ROOT;
2211  		c->size_tree = RB_ROOT;
2212  		c->orph_tree = RB_ROOT;
2213  		INIT_LIST_HEAD(&c->infos_list);
2214  		INIT_LIST_HEAD(&c->idx_gc);
2215  		INIT_LIST_HEAD(&c->replay_list);
2216  		INIT_LIST_HEAD(&c->replay_buds);
2217  		INIT_LIST_HEAD(&c->uncat_list);
2218  		INIT_LIST_HEAD(&c->empty_list);
2219  		INIT_LIST_HEAD(&c->freeable_list);
2220  		INIT_LIST_HEAD(&c->frdi_idx_list);
2221  		INIT_LIST_HEAD(&c->unclean_leb_list);
2222  		INIT_LIST_HEAD(&c->old_buds);
2223  		INIT_LIST_HEAD(&c->orph_list);
2224  		INIT_LIST_HEAD(&c->orph_new);
2225  		c->no_chk_data_crc = 1;
2226  
2227  		c->highest_inum = UBIFS_FIRST_INO;
2228  		c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
2229  
2230  		ubi_get_volume_info(ubi, &c->vi);
2231  		ubi_get_device_info(c->vi.ubi_num, &c->di);
2232  	}
2233  	return c;
2234  }
2235  
2236  static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
2237  {
2238  	struct ubifs_info *c = sb->s_fs_info;
2239  	struct inode *root;
2240  	int err;
2241  
2242  	c->vfs_sb = sb;
2243  #ifndef __UBOOT__
2244  	/* Re-open the UBI device in read-write mode */
2245  	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
2246  #else
2247  	/* U-Boot read only mode */
2248  	c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READONLY);
2249  #endif
2250  
2251  	if (IS_ERR(c->ubi)) {
2252  		err = PTR_ERR(c->ubi);
2253  		goto out;
2254  	}
2255  
2256  #ifndef __UBOOT__
2257  	/*
2258  	 * UBIFS provides 'backing_dev_info' in order to disable read-ahead. For
2259  	 * UBIFS, I/O is not deferred, it is done immediately in readpage,
2260  	 * which means the user would have to wait not just for their own I/O
2261  	 * but the read-ahead I/O as well i.e. completely pointless.
2262  	 *
2263  	 * Read-ahead will be disabled because @c->bdi.ra_pages is 0.
2264  	 */
2265  	c->bdi.name = "ubifs",
2266  	c->bdi.capabilities = 0;
2267  	err  = bdi_init(&c->bdi);
2268  	if (err)
2269  		goto out_close;
2270  	err = bdi_register(&c->bdi, NULL, "ubifs_%d_%d",
2271  			   c->vi.ubi_num, c->vi.vol_id);
2272  	if (err)
2273  		goto out_bdi;
2274  
2275  	err = ubifs_parse_options(c, data, 0);
2276  	if (err)
2277  		goto out_bdi;
2278  
2279  	sb->s_bdi = &c->bdi;
2280  #endif
2281  	sb->s_fs_info = c;
2282  	sb->s_magic = UBIFS_SUPER_MAGIC;
2283  	sb->s_blocksize = UBIFS_BLOCK_SIZE;
2284  	sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
2285  	sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
2286  	if (c->max_inode_sz > MAX_LFS_FILESIZE)
2287  		sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
2288  	sb->s_op = &ubifs_super_operations;
2289  #ifndef __UBOOT__
2290  	sb->s_xattr = ubifs_xattr_handlers;
2291  #endif
2292  
2293  	mutex_lock(&c->umount_mutex);
2294  	err = mount_ubifs(c);
2295  	if (err) {
2296  		ubifs_assert(err < 0);
2297  		goto out_unlock;
2298  	}
2299  
2300  	/* Read the root inode */
2301  	root = ubifs_iget(sb, UBIFS_ROOT_INO);
2302  	if (IS_ERR(root)) {
2303  		err = PTR_ERR(root);
2304  		goto out_umount;
2305  	}
2306  
2307  #ifndef __UBOOT__
2308  	sb->s_root = d_make_root(root);
2309  	if (!sb->s_root) {
2310  		err = -ENOMEM;
2311  		goto out_umount;
2312  	}
2313  #else
2314  	sb->s_root = NULL;
2315  #endif
2316  
2317  	mutex_unlock(&c->umount_mutex);
2318  	return 0;
2319  
2320  out_umount:
2321  	ubifs_umount(c);
2322  out_unlock:
2323  	mutex_unlock(&c->umount_mutex);
2324  #ifndef __UBOOT__
2325  out_bdi:
2326  	bdi_destroy(&c->bdi);
2327  out_close:
2328  #endif
2329  	ubi_close_volume(c->ubi);
2330  out:
2331  	return err;
2332  }
2333  
2334  static int sb_test(struct super_block *sb, void *data)
2335  {
2336  	struct ubifs_info *c1 = data;
2337  	struct ubifs_info *c = sb->s_fs_info;
2338  
2339  	return c->vi.cdev == c1->vi.cdev;
2340  }
2341  
2342  static int sb_set(struct super_block *sb, void *data)
2343  {
2344  	sb->s_fs_info = data;
2345  	return set_anon_super(sb, NULL);
2346  }
2347  
2348  static struct super_block *alloc_super(struct file_system_type *type, int flags)
2349  {
2350  	struct super_block *s;
2351  	int err;
2352  
2353  	s = kzalloc(sizeof(struct super_block),  GFP_USER);
2354  	if (!s) {
2355  		err = -ENOMEM;
2356  		return ERR_PTR(err);
2357  	}
2358  
2359  	INIT_HLIST_NODE(&s->s_instances);
2360  	INIT_LIST_HEAD(&s->s_inodes);
2361  	s->s_time_gran = 1000000000;
2362  	s->s_flags = flags;
2363  
2364  	return s;
2365  }
2366  
2367  /**
2368   *	sget	-	find or create a superblock
2369   *	@type:	filesystem type superblock should belong to
2370   *	@test:	comparison callback
2371   *	@set:	setup callback
2372   *	@flags:	mount flags
2373   *	@data:	argument to each of them
2374   */
2375  struct super_block *sget(struct file_system_type *type,
2376  			int (*test)(struct super_block *,void *),
2377  			int (*set)(struct super_block *,void *),
2378  			int flags,
2379  			void *data)
2380  {
2381  	struct super_block *s = NULL;
2382  #ifndef __UBOOT__
2383  	struct super_block *old;
2384  #endif
2385  	int err;
2386  
2387  #ifndef __UBOOT__
2388  retry:
2389  	spin_lock(&sb_lock);
2390  	if (test) {
2391  		hlist_for_each_entry(old, &type->fs_supers, s_instances) {
2392  			if (!test(old, data))
2393  				continue;
2394  			if (!grab_super(old))
2395  				goto retry;
2396  			if (s) {
2397  				up_write(&s->s_umount);
2398  				destroy_super(s);
2399  				s = NULL;
2400  			}
2401  			return old;
2402  		}
2403  	}
2404  #endif
2405  	if (!s) {
2406  		spin_unlock(&sb_lock);
2407  		s = alloc_super(type, flags);
2408  		if (!s)
2409  			return ERR_PTR(-ENOMEM);
2410  #ifndef __UBOOT__
2411  		goto retry;
2412  #endif
2413  	}
2414  
2415  	err = set(s, data);
2416  	if (err) {
2417  #ifndef __UBOOT__
2418  		spin_unlock(&sb_lock);
2419  		up_write(&s->s_umount);
2420  		destroy_super(s);
2421  #endif
2422  		return ERR_PTR(err);
2423  	}
2424  	s->s_type = type;
2425  #ifndef __UBOOT__
2426  	strlcpy(s->s_id, type->name, sizeof(s->s_id));
2427  	list_add_tail(&s->s_list, &super_blocks);
2428  #else
2429  	strncpy(s->s_id, type->name, sizeof(s->s_id));
2430  #endif
2431  	hlist_add_head(&s->s_instances, &type->fs_supers);
2432  #ifndef __UBOOT__
2433  	spin_unlock(&sb_lock);
2434  	get_filesystem(type);
2435  	register_shrinker(&s->s_shrink);
2436  #endif
2437  	return s;
2438  }
2439  
2440  EXPORT_SYMBOL(sget);
2441  
2442  
2443  static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
2444  			const char *name, void *data)
2445  {
2446  	struct ubi_volume_desc *ubi;
2447  	struct ubifs_info *c;
2448  	struct super_block *sb;
2449  	int err;
2450  
2451  	dbg_gen("name %s, flags %#x", name, flags);
2452  
2453  	/*
2454  	 * Get UBI device number and volume ID. Mount it read-only so far
2455  	 * because this might be a new mount point, and UBI allows only one
2456  	 * read-write user at a time.
2457  	 */
2458  	ubi = open_ubi(name, UBI_READONLY);
2459  	if (IS_ERR(ubi)) {
2460  		pr_err("UBIFS error (pid: %d): cannot open \"%s\", error %d",
2461  		       current->pid, name, (int)PTR_ERR(ubi));
2462  		return ERR_CAST(ubi);
2463  	}
2464  
2465  	c = alloc_ubifs_info(ubi);
2466  	if (!c) {
2467  		err = -ENOMEM;
2468  		goto out_close;
2469  	}
2470  
2471  	dbg_gen("opened ubi%d_%d", c->vi.ubi_num, c->vi.vol_id);
2472  
2473  	sb = sget(fs_type, sb_test, sb_set, flags, c);
2474  	if (IS_ERR(sb)) {
2475  		err = PTR_ERR(sb);
2476  		kfree(c);
2477  		goto out_close;
2478  	}
2479  
2480  	if (sb->s_root) {
2481  		struct ubifs_info *c1 = sb->s_fs_info;
2482  		kfree(c);
2483  		/* A new mount point for already mounted UBIFS */
2484  		dbg_gen("this ubi volume is already mounted");
2485  		if (!!(flags & MS_RDONLY) != c1->ro_mount) {
2486  			err = -EBUSY;
2487  			goto out_deact;
2488  		}
2489  	} else {
2490  		err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
2491  		if (err)
2492  			goto out_deact;
2493  		/* We do not support atime */
2494  		sb->s_flags |= MS_ACTIVE | MS_NOATIME;
2495  	}
2496  
2497  	/* 'fill_super()' opens ubi again so we must close it here */
2498  	ubi_close_volume(ubi);
2499  
2500  #ifdef __UBOOT__
2501  	ubifs_sb = sb;
2502  	return 0;
2503  #else
2504  	return dget(sb->s_root);
2505  #endif
2506  
2507  out_deact:
2508  #ifndef __UBOOT__
2509  	deactivate_locked_super(sb);
2510  #endif
2511  out_close:
2512  	ubi_close_volume(ubi);
2513  	return ERR_PTR(err);
2514  }
2515  
2516  static void kill_ubifs_super(struct super_block *s)
2517  {
2518  	struct ubifs_info *c = s->s_fs_info;
2519  #ifndef __UBOOT__
2520  	kill_anon_super(s);
2521  #endif
2522  	kfree(c);
2523  }
2524  
2525  static struct file_system_type ubifs_fs_type = {
2526  	.name    = "ubifs",
2527  	.owner   = THIS_MODULE,
2528  	.mount   = ubifs_mount,
2529  	.kill_sb = kill_ubifs_super,
2530  };
2531  #ifndef __UBOOT__
2532  MODULE_ALIAS_FS("ubifs");
2533  
2534  /*
2535   * Inode slab cache constructor.
2536   */
2537  static void inode_slab_ctor(void *obj)
2538  {
2539  	struct ubifs_inode *ui = obj;
2540  	inode_init_once(&ui->vfs_inode);
2541  }
2542  
2543  static int __init ubifs_init(void)
2544  #else
2545  int ubifs_init(void)
2546  #endif
2547  {
2548  	int err;
2549  
2550  	BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
2551  
2552  	/* Make sure node sizes are 8-byte aligned */
2553  	BUILD_BUG_ON(UBIFS_CH_SZ        & 7);
2554  	BUILD_BUG_ON(UBIFS_INO_NODE_SZ  & 7);
2555  	BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
2556  	BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
2557  	BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
2558  	BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
2559  	BUILD_BUG_ON(UBIFS_SB_NODE_SZ   & 7);
2560  	BUILD_BUG_ON(UBIFS_MST_NODE_SZ  & 7);
2561  	BUILD_BUG_ON(UBIFS_REF_NODE_SZ  & 7);
2562  	BUILD_BUG_ON(UBIFS_CS_NODE_SZ   & 7);
2563  	BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
2564  
2565  	BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
2566  	BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
2567  	BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
2568  	BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ  & 7);
2569  	BUILD_BUG_ON(UBIFS_MAX_NODE_SZ      & 7);
2570  	BUILD_BUG_ON(MIN_WRITE_SZ           & 7);
2571  
2572  	/* Check min. node size */
2573  	BUILD_BUG_ON(UBIFS_INO_NODE_SZ  < MIN_WRITE_SZ);
2574  	BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
2575  	BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
2576  	BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
2577  
2578  	BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
2579  	BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
2580  	BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
2581  	BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ  > UBIFS_MAX_NODE_SZ);
2582  
2583  	/* Defined node sizes */
2584  	BUILD_BUG_ON(UBIFS_SB_NODE_SZ  != 4096);
2585  	BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
2586  	BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
2587  	BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
2588  
2589  	/*
2590  	 * We use 2 bit wide bit-fields to store compression type, which should
2591  	 * be amended if more compressors are added. The bit-fields are:
2592  	 * @compr_type in 'struct ubifs_inode', @default_compr in
2593  	 * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'.
2594  	 */
2595  	BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4);
2596  
2597  	/*
2598  	 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
2599  	 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
2600  	 */
2601  	if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
2602  		pr_err("UBIFS error (pid %d): VFS page cache size is %u bytes, but UBIFS requires at least 4096 bytes",
2603  		       current->pid, (unsigned int)PAGE_CACHE_SIZE);
2604  		return -EINVAL;
2605  	}
2606  
2607  #ifndef __UBOOT__
2608  	ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
2609  				sizeof(struct ubifs_inode), 0,
2610  				SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
2611  				&inode_slab_ctor);
2612  	if (!ubifs_inode_slab)
2613  		return -ENOMEM;
2614  
2615  	err = register_shrinker(&ubifs_shrinker_info);
2616  	if (err)
2617  		goto out_slab;
2618  #endif
2619  
2620  	err = ubifs_compressors_init();
2621  	if (err)
2622  		goto out_shrinker;
2623  
2624  #ifndef __UBOOT__
2625  	err = dbg_debugfs_init();
2626  	if (err)
2627  		goto out_compr;
2628  
2629  	err = register_filesystem(&ubifs_fs_type);
2630  	if (err) {
2631  		pr_err("UBIFS error (pid %d): cannot register file system, error %d",
2632  		       current->pid, err);
2633  		goto out_dbg;
2634  	}
2635  #endif
2636  	return 0;
2637  
2638  #ifndef __UBOOT__
2639  out_dbg:
2640  	dbg_debugfs_exit();
2641  out_compr:
2642  	ubifs_compressors_exit();
2643  #endif
2644  out_shrinker:
2645  #ifndef __UBOOT__
2646  	unregister_shrinker(&ubifs_shrinker_info);
2647  out_slab:
2648  #endif
2649  	kmem_cache_destroy(ubifs_inode_slab);
2650  	return err;
2651  }
2652  /* late_initcall to let compressors initialize first */
2653  late_initcall(ubifs_init);
2654  
2655  #ifndef __UBOOT__
2656  static void __exit ubifs_exit(void)
2657  {
2658  	ubifs_assert(list_empty(&ubifs_infos));
2659  	ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
2660  
2661  	dbg_debugfs_exit();
2662  	ubifs_compressors_exit();
2663  	unregister_shrinker(&ubifs_shrinker_info);
2664  
2665  	/*
2666  	 * Make sure all delayed rcu free inodes are flushed before we
2667  	 * destroy cache.
2668  	 */
2669  	rcu_barrier();
2670  	kmem_cache_destroy(ubifs_inode_slab);
2671  	unregister_filesystem(&ubifs_fs_type);
2672  }
2673  module_exit(ubifs_exit);
2674  
2675  MODULE_LICENSE("GPL");
2676  MODULE_VERSION(__stringify(UBIFS_VERSION));
2677  MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
2678  MODULE_DESCRIPTION("UBIFS - UBI File System");
2679  #else
2680  int uboot_ubifs_mount(char *vol_name)
2681  {
2682  	struct dentry *ret;
2683  	int flags;
2684  
2685  	/*
2686  	 * First unmount if allready mounted
2687  	 */
2688  	if (ubifs_sb)
2689  		ubifs_umount(ubifs_sb->s_fs_info);
2690  
2691  	/*
2692  	 * Mount in read-only mode
2693  	 */
2694  	flags = MS_RDONLY;
2695  	ret = ubifs_mount(&ubifs_fs_type, flags, vol_name, NULL);
2696  	if (IS_ERR(ret)) {
2697  		printf("Error reading superblock on volume '%s' " \
2698  			"errno=%d!\n", vol_name, (int)PTR_ERR(ret));
2699  		return -1;
2700  	}
2701  
2702  	return 0;
2703  }
2704  #endif
2705