blob: 13e90b0dd95d3338aaf1ebd7b912f1b70d034da5 [file] [log] [blame]
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
20 * Adrian Hunter
21 */
22
23/*
24 * This file implements UBIFS initialization and VFS superblock operations. Some
25 * initialization stuff which is rather large and complex is placed at
26 * corresponding subsystems, but most of it is here.
27 */
28
29#include <linux/init.h>
30#include <linux/slab.h>
31#include <linux/module.h>
32#include <linux/ctype.h>
33#include <linux/random.h>
34#include <linux/kthread.h>
35#include <linux/parser.h>
36#include <linux/seq_file.h>
37#include <linux/mount.h>
38#include "ubifs.h"
39
40/* Slab cache for UBIFS inodes */
41struct kmem_cache *ubifs_inode_slab;
42
43/* UBIFS TNC shrinker description */
44static struct shrinker ubifs_shrinker_info = {
45 .shrink = ubifs_shrinker,
46 .seeks = DEFAULT_SEEKS,
47};
48
49/**
50 * validate_inode - validate inode.
51 * @c: UBIFS file-system description object
52 * @inode: the inode to validate
53 *
54 * This is a helper function for 'ubifs_iget()' which validates various fields
55 * of a newly built inode to make sure they contain sane values and prevent
56 * possible vulnerabilities. Returns zero if the inode is all right and
57 * a non-zero error code if not.
58 */
59static int validate_inode(struct ubifs_info *c, const struct inode *inode)
60{
61 int err;
62 const struct ubifs_inode *ui = ubifs_inode(inode);
63
64 if (inode->i_size > c->max_inode_sz) {
65 ubifs_err("inode is too large (%lld)",
66 (long long)inode->i_size);
67 return 1;
68 }
69
70 if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
71 ubifs_err("unknown compression type %d", ui->compr_type);
72 return 2;
73 }
74
75 if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
76 return 3;
77
78 if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
79 return 4;
80
81 if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG)
82 return 5;
83
84 if (!ubifs_compr_present(ui->compr_type)) {
85 ubifs_warn("inode %lu uses '%s' compression, but it was not "
86 "compiled in", inode->i_ino,
87 ubifs_compr_name(ui->compr_type));
88 }
89
90 err = dbg_check_dir_size(c, inode);
91 return err;
92}
93
94struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
95{
96 int err;
97 union ubifs_key key;
98 struct ubifs_ino_node *ino;
99 struct ubifs_info *c = sb->s_fs_info;
100 struct inode *inode;
101 struct ubifs_inode *ui;
102
103 dbg_gen("inode %lu", inum);
104
105 inode = iget_locked(sb, inum);
106 if (!inode)
107 return ERR_PTR(-ENOMEM);
108 if (!(inode->i_state & I_NEW))
109 return inode;
110 ui = ubifs_inode(inode);
111
112 ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
113 if (!ino) {
114 err = -ENOMEM;
115 goto out;
116 }
117
118 ino_key_init(c, &key, inode->i_ino);
119
120 err = ubifs_tnc_lookup(c, &key, ino);
121 if (err)
122 goto out_ino;
123
124 inode->i_flags |= (S_NOCMTIME | S_NOATIME);
125 inode->i_nlink = le32_to_cpu(ino->nlink);
126 inode->i_uid = le32_to_cpu(ino->uid);
127 inode->i_gid = le32_to_cpu(ino->gid);
128 inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec);
129 inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
130 inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec);
131 inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
132 inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec);
133 inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
134 inode->i_mode = le32_to_cpu(ino->mode);
135 inode->i_size = le64_to_cpu(ino->size);
136
137 ui->data_len = le32_to_cpu(ino->data_len);
138 ui->flags = le32_to_cpu(ino->flags);
139 ui->compr_type = le16_to_cpu(ino->compr_type);
140 ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
141 ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
142 ui->xattr_size = le32_to_cpu(ino->xattr_size);
143 ui->xattr_names = le32_to_cpu(ino->xattr_names);
144 ui->synced_i_size = ui->ui_size = inode->i_size;
145
146 ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
147
148 err = validate_inode(c, inode);
149 if (err)
150 goto out_invalid;
151
152 /* Disable readahead */
153 inode->i_mapping->backing_dev_info = &c->bdi;
154
155 switch (inode->i_mode & S_IFMT) {
156 case S_IFREG:
157 inode->i_mapping->a_ops = &ubifs_file_address_operations;
158 inode->i_op = &ubifs_file_inode_operations;
159 inode->i_fop = &ubifs_file_operations;
160 if (ui->xattr) {
161 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
162 if (!ui->data) {
163 err = -ENOMEM;
164 goto out_ino;
165 }
166 memcpy(ui->data, ino->data, ui->data_len);
167 ((char *)ui->data)[ui->data_len] = '\0';
168 } else if (ui->data_len != 0) {
169 err = 10;
170 goto out_invalid;
171 }
172 break;
173 case S_IFDIR:
174 inode->i_op = &ubifs_dir_inode_operations;
175 inode->i_fop = &ubifs_dir_operations;
176 if (ui->data_len != 0) {
177 err = 11;
178 goto out_invalid;
179 }
180 break;
181 case S_IFLNK:
182 inode->i_op = &ubifs_symlink_inode_operations;
183 if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
184 err = 12;
185 goto out_invalid;
186 }
187 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
188 if (!ui->data) {
189 err = -ENOMEM;
190 goto out_ino;
191 }
192 memcpy(ui->data, ino->data, ui->data_len);
193 ((char *)ui->data)[ui->data_len] = '\0';
194 break;
195 case S_IFBLK:
196 case S_IFCHR:
197 {
198 dev_t rdev;
199 union ubifs_dev_desc *dev;
200
201 ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
202 if (!ui->data) {
203 err = -ENOMEM;
204 goto out_ino;
205 }
206
207 dev = (union ubifs_dev_desc *)ino->data;
208 if (ui->data_len == sizeof(dev->new))
209 rdev = new_decode_dev(le32_to_cpu(dev->new));
210 else if (ui->data_len == sizeof(dev->huge))
211 rdev = huge_decode_dev(le64_to_cpu(dev->huge));
212 else {
213 err = 13;
214 goto out_invalid;
215 }
216 memcpy(ui->data, ino->data, ui->data_len);
217 inode->i_op = &ubifs_file_inode_operations;
218 init_special_inode(inode, inode->i_mode, rdev);
219 break;
220 }
221 case S_IFSOCK:
222 case S_IFIFO:
223 inode->i_op = &ubifs_file_inode_operations;
224 init_special_inode(inode, inode->i_mode, 0);
225 if (ui->data_len != 0) {
226 err = 14;
227 goto out_invalid;
228 }
229 break;
230 default:
231 err = 15;
232 goto out_invalid;
233 }
234
235 kfree(ino);
236 ubifs_set_inode_flags(inode);
237 unlock_new_inode(inode);
238 return inode;
239
240out_invalid:
241 ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err);
242 dbg_dump_node(c, ino);
243 dbg_dump_inode(c, inode);
244 err = -EINVAL;
245out_ino:
246 kfree(ino);
247out:
248 ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err);
249 iget_failed(inode);
250 return ERR_PTR(err);
251}
252
253static struct inode *ubifs_alloc_inode(struct super_block *sb)
254{
255 struct ubifs_inode *ui;
256
257 ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
258 if (!ui)
259 return NULL;
260
261 memset((void *)ui + sizeof(struct inode), 0,
262 sizeof(struct ubifs_inode) - sizeof(struct inode));
263 mutex_init(&ui->ui_mutex);
264 spin_lock_init(&ui->ui_lock);
265 return &ui->vfs_inode;
266};
267
268static void ubifs_destroy_inode(struct inode *inode)
269{
270 struct ubifs_inode *ui = ubifs_inode(inode);
271
272 kfree(ui->data);
273 kmem_cache_free(ubifs_inode_slab, inode);
274}
275
276/*
277 * Note, Linux write-back code calls this without 'i_mutex'.
278 */
279static int ubifs_write_inode(struct inode *inode, int wait)
280{
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300281 int err = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300282 struct ubifs_info *c = inode->i_sb->s_fs_info;
283 struct ubifs_inode *ui = ubifs_inode(inode);
284
285 ubifs_assert(!ui->xattr);
286 if (is_bad_inode(inode))
287 return 0;
288
289 mutex_lock(&ui->ui_mutex);
290 /*
291 * Due to races between write-back forced by budgeting
292 * (see 'sync_some_inodes()') and pdflush write-back, the inode may
293 * have already been synchronized, do not do this again. This might
294 * also happen if it was synchronized in an VFS operation, e.g.
295 * 'ubifs_link()'.
296 */
297 if (!ui->dirty) {
298 mutex_unlock(&ui->ui_mutex);
299 return 0;
300 }
301
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300302 /*
303 * As an optimization, do not write orphan inodes to the media just
304 * because this is not needed.
305 */
306 dbg_gen("inode %lu, mode %#x, nlink %u",
307 inode->i_ino, (int)inode->i_mode, inode->i_nlink);
308 if (inode->i_nlink) {
309 err = ubifs_jnl_write_inode(c, inode, 0);
310 if (err)
311 ubifs_err("can't write inode %lu, error %d",
312 inode->i_ino, err);
313 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300314
315 ui->dirty = 0;
316 mutex_unlock(&ui->ui_mutex);
317 ubifs_release_dirty_inode_budget(c, ui);
318 return err;
319}
320
321static void ubifs_delete_inode(struct inode *inode)
322{
323 int err;
324 struct ubifs_info *c = inode->i_sb->s_fs_info;
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300325 struct ubifs_inode *ui = ubifs_inode(inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300326
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300327 if (ui->xattr)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300328 /*
329 * Extended attribute inode deletions are fully handled in
330 * 'ubifs_removexattr()'. These inodes are special and have
331 * limited usage, so there is nothing to do here.
332 */
333 goto out;
334
Artem Bityutskiy7d32c2b2008-07-18 18:54:29 +0300335 dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300336 ubifs_assert(!atomic_read(&inode->i_count));
337 ubifs_assert(inode->i_nlink == 0);
338
339 truncate_inode_pages(&inode->i_data, 0);
340 if (is_bad_inode(inode))
341 goto out;
342
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300343 ui->ui_size = inode->i_size = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300344 err = ubifs_jnl_write_inode(c, inode, 1);
345 if (err)
346 /*
347 * Worst case we have a lost orphan inode wasting space, so a
348 * simple error message is ok here.
349 */
350 ubifs_err("can't write inode %lu, error %d", inode->i_ino, err);
351out:
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300352 if (ui->dirty)
353 ubifs_release_dirty_inode_budget(c, ui);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300354 clear_inode(inode);
355}
356
357static void ubifs_dirty_inode(struct inode *inode)
358{
359 struct ubifs_inode *ui = ubifs_inode(inode);
360
361 ubifs_assert(mutex_is_locked(&ui->ui_mutex));
362 if (!ui->dirty) {
363 ui->dirty = 1;
364 dbg_gen("inode %lu", inode->i_ino);
365 }
366}
367
368static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
369{
370 struct ubifs_info *c = dentry->d_sb->s_fs_info;
371 unsigned long long free;
372
373 free = ubifs_budg_get_free_space(c);
374 dbg_gen("free space %lld bytes (%lld blocks)",
375 free, free >> UBIFS_BLOCK_SHIFT);
376
377 buf->f_type = UBIFS_SUPER_MAGIC;
378 buf->f_bsize = UBIFS_BLOCK_SIZE;
379 buf->f_blocks = c->block_cnt;
380 buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
381 if (free > c->report_rp_size)
382 buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
383 else
384 buf->f_bavail = 0;
385 buf->f_files = 0;
386 buf->f_ffree = 0;
387 buf->f_namelen = UBIFS_MAX_NLEN;
388
389 return 0;
390}
391
392static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
393{
394 struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
395
396 if (c->mount_opts.unmount_mode == 2)
397 seq_printf(s, ",fast_unmount");
398 else if (c->mount_opts.unmount_mode == 1)
399 seq_printf(s, ",norm_unmount");
400
401 return 0;
402}
403
404static int ubifs_sync_fs(struct super_block *sb, int wait)
405{
406 struct ubifs_info *c = sb->s_fs_info;
407 int i, ret = 0, err;
408
409 if (c->jheads)
410 for (i = 0; i < c->jhead_cnt; i++) {
411 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
412 if (err && !ret)
413 ret = err;
414 }
415 /*
416 * We ought to call sync for c->ubi but it does not have one. If it had
417 * it would in turn call mtd->sync, however mtd operations are
418 * synchronous anyway, so we don't lose any sleep here.
419 */
420 return ret;
421}
422
423/**
424 * init_constants_early - initialize UBIFS constants.
425 * @c: UBIFS file-system description object
426 *
427 * This function initialize UBIFS constants which do not need the superblock to
428 * be read. It also checks that the UBI volume satisfies basic UBIFS
429 * requirements. Returns zero in case of success and a negative error code in
430 * case of failure.
431 */
432static int init_constants_early(struct ubifs_info *c)
433{
434 if (c->vi.corrupted) {
435 ubifs_warn("UBI volume is corrupted - read-only mode");
436 c->ro_media = 1;
437 }
438
439 if (c->di.ro_mode) {
440 ubifs_msg("read-only UBI device");
441 c->ro_media = 1;
442 }
443
444 if (c->vi.vol_type == UBI_STATIC_VOLUME) {
445 ubifs_msg("static UBI volume - read-only mode");
446 c->ro_media = 1;
447 }
448
449 c->leb_cnt = c->vi.size;
450 c->leb_size = c->vi.usable_leb_size;
451 c->half_leb_size = c->leb_size / 2;
452 c->min_io_size = c->di.min_io_size;
453 c->min_io_shift = fls(c->min_io_size) - 1;
454
455 if (c->leb_size < UBIFS_MIN_LEB_SZ) {
456 ubifs_err("too small LEBs (%d bytes), min. is %d bytes",
457 c->leb_size, UBIFS_MIN_LEB_SZ);
458 return -EINVAL;
459 }
460
461 if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
462 ubifs_err("too few LEBs (%d), min. is %d",
463 c->leb_cnt, UBIFS_MIN_LEB_CNT);
464 return -EINVAL;
465 }
466
467 if (!is_power_of_2(c->min_io_size)) {
468 ubifs_err("bad min. I/O size %d", c->min_io_size);
469 return -EINVAL;
470 }
471
472 /*
473 * UBIFS aligns all node to 8-byte boundary, so to make function in
474 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
475 * less than 8.
476 */
477 if (c->min_io_size < 8) {
478 c->min_io_size = 8;
479 c->min_io_shift = 3;
480 }
481
482 c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
483 c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
484
485 /*
486 * Initialize node length ranges which are mostly needed for node
487 * length validation.
488 */
489 c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ;
490 c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ;
491 c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ;
492 c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ;
493 c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
494 c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ;
495
496 c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ;
497 c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ;
498 c->ranges[UBIFS_ORPH_NODE].min_len =
499 UBIFS_ORPH_NODE_SZ + sizeof(__le64);
500 c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
501 c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
502 c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
503 c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
504 c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
505 c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
506 c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
507 /*
508 * Minimum indexing node size is amended later when superblock is
509 * read and the key length is known.
510 */
511 c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
512 /*
513 * Maximum indexing node size is amended later when superblock is
514 * read and the fanout is known.
515 */
516 c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
517
518 /*
519 * Initialize dead and dark LEB space watermarks.
520 *
521 * Dead space is the space which cannot be used. Its watermark is
522 * equivalent to min. I/O unit or minimum node size if it is greater
523 * then min. I/O unit.
524 *
525 * Dark space is the space which might be used, or might not, depending
526 * on which node should be written to the LEB. Its watermark is
527 * equivalent to maximum UBIFS node size.
528 */
529 c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
530 c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
531
532 return 0;
533}
534
535/**
536 * bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
537 * @c: UBIFS file-system description object
538 * @lnum: LEB the write-buffer was synchronized to
539 * @free: how many free bytes left in this LEB
540 * @pad: how many bytes were padded
541 *
542 * This is a callback function which is called by the I/O unit when the
543 * write-buffer is synchronized. We need this to correctly maintain space
544 * accounting in bud logical eraseblocks. This function returns zero in case of
545 * success and a negative error code in case of failure.
546 *
547 * This function actually belongs to the journal, but we keep it here because
548 * we want to keep it static.
549 */
550static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
551{
552 return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
553}
554
555/*
556 * init_constants_late - initialize UBIFS constants.
557 * @c: UBIFS file-system description object
558 *
559 * This is a helper function which initializes various UBIFS constants after
560 * the superblock has been read. It also checks various UBIFS parameters and
561 * makes sure they are all right. Returns zero in case of success and a
562 * negative error code in case of failure.
563 */
564static int init_constants_late(struct ubifs_info *c)
565{
566 int tmp, err;
567 uint64_t tmp64;
568
569 c->main_bytes = (long long)c->main_lebs * c->leb_size;
570 c->max_znode_sz = sizeof(struct ubifs_znode) +
571 c->fanout * sizeof(struct ubifs_zbranch);
572
573 tmp = ubifs_idx_node_sz(c, 1);
574 c->ranges[UBIFS_IDX_NODE].min_len = tmp;
575 c->min_idx_node_sz = ALIGN(tmp, 8);
576
577 tmp = ubifs_idx_node_sz(c, c->fanout);
578 c->ranges[UBIFS_IDX_NODE].max_len = tmp;
579 c->max_idx_node_sz = ALIGN(tmp, 8);
580
581 /* Make sure LEB size is large enough to fit full commit */
582 tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
583 tmp = ALIGN(tmp, c->min_io_size);
584 if (tmp > c->leb_size) {
585 dbg_err("too small LEB size %d, at least %d needed",
586 c->leb_size, tmp);
587 return -EINVAL;
588 }
589
590 /*
591 * Make sure that the log is large enough to fit reference nodes for
592 * all buds plus one reserved LEB.
593 */
594 tmp64 = c->max_bud_bytes;
595 tmp = do_div(tmp64, c->leb_size);
596 c->max_bud_cnt = tmp64 + !!tmp;
597 tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
598 tmp /= c->leb_size;
599 tmp += 1;
600 if (c->log_lebs < tmp) {
601 dbg_err("too small log %d LEBs, required min. %d LEBs",
602 c->log_lebs, tmp);
603 return -EINVAL;
604 }
605
606 /*
607 * When budgeting we assume worst-case scenarios when the pages are not
608 * be compressed and direntries are of the maximum size.
609 *
610 * Note, data, which may be stored in inodes is budgeted separately, so
611 * it is not included into 'c->inode_budget'.
612 */
613 c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
614 c->inode_budget = UBIFS_INO_NODE_SZ;
615 c->dent_budget = UBIFS_MAX_DENT_NODE_SZ;
616
617 /*
618 * When the amount of flash space used by buds becomes
619 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
620 * The writers are unblocked when the commit is finished. To avoid
621 * writers to be blocked UBIFS initiates background commit in advance,
622 * when number of bud bytes becomes above the limit defined below.
623 */
624 c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
625
626 /*
627 * Ensure minimum journal size. All the bytes in the journal heads are
628 * considered to be used, when calculating the current journal usage.
629 * Consequently, if the journal is too small, UBIFS will treat it as
630 * always full.
631 */
632 tmp64 = (uint64_t)(c->jhead_cnt + 1) * c->leb_size + 1;
633 if (c->bg_bud_bytes < tmp64)
634 c->bg_bud_bytes = tmp64;
635 if (c->max_bud_bytes < tmp64 + c->leb_size)
636 c->max_bud_bytes = tmp64 + c->leb_size;
637
638 err = ubifs_calc_lpt_geom(c);
639 if (err)
640 return err;
641
642 c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
643
644 /*
645 * Calculate total amount of FS blocks. This number is not used
646 * internally because it does not make much sense for UBIFS, but it is
647 * necessary to report something for the 'statfs()' call.
648 *
649 * Subtract the LEB reserved for GC and the LEB which is reserved for
650 * deletions.
651 *
652 * Review 'ubifs_calc_available()' if changing this calculation.
653 */
654 tmp64 = c->main_lebs - 2;
655 tmp64 *= (uint64_t)c->leb_size - c->dark_wm;
656 tmp64 = ubifs_reported_space(c, tmp64);
657 c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
658
659 return 0;
660}
661
662/**
663 * take_gc_lnum - reserve GC LEB.
664 * @c: UBIFS file-system description object
665 *
666 * This function ensures that the LEB reserved for garbage collection is
667 * unmapped and is marked as "taken" in lprops. We also have to set free space
668 * to LEB size and dirty space to zero, because lprops may contain out-of-date
669 * information if the file-system was un-mounted before it has been committed.
670 * This function returns zero in case of success and a negative error code in
671 * case of failure.
672 */
673static int take_gc_lnum(struct ubifs_info *c)
674{
675 int err;
676
677 if (c->gc_lnum == -1) {
678 ubifs_err("no LEB for GC");
679 return -EINVAL;
680 }
681
682 err = ubifs_leb_unmap(c, c->gc_lnum);
683 if (err)
684 return err;
685
686 /* And we have to tell lprops that this LEB is taken */
687 err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
688 LPROPS_TAKEN, 0, 0);
689 return err;
690}
691
692/**
693 * alloc_wbufs - allocate write-buffers.
694 * @c: UBIFS file-system description object
695 *
696 * This helper function allocates and initializes UBIFS write-buffers. Returns
697 * zero in case of success and %-ENOMEM in case of failure.
698 */
699static int alloc_wbufs(struct ubifs_info *c)
700{
701 int i, err;
702
703 c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead),
704 GFP_KERNEL);
705 if (!c->jheads)
706 return -ENOMEM;
707
708 /* Initialize journal heads */
709 for (i = 0; i < c->jhead_cnt; i++) {
710 INIT_LIST_HEAD(&c->jheads[i].buds_list);
711 err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
712 if (err)
713 return err;
714
715 c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
716 c->jheads[i].wbuf.jhead = i;
717 }
718
719 c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM;
720 /*
721 * Garbage Collector head likely contains long-term data and
722 * does not need to be synchronized by timer.
723 */
724 c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
725 c->jheads[GCHD].wbuf.timeout = 0;
726
727 return 0;
728}
729
730/**
731 * free_wbufs - free write-buffers.
732 * @c: UBIFS file-system description object
733 */
734static void free_wbufs(struct ubifs_info *c)
735{
736 int i;
737
738 if (c->jheads) {
739 for (i = 0; i < c->jhead_cnt; i++) {
740 kfree(c->jheads[i].wbuf.buf);
741 kfree(c->jheads[i].wbuf.inodes);
742 }
743 kfree(c->jheads);
744 c->jheads = NULL;
745 }
746}
747
748/**
749 * free_orphans - free orphans.
750 * @c: UBIFS file-system description object
751 */
752static void free_orphans(struct ubifs_info *c)
753{
754 struct ubifs_orphan *orph;
755
756 while (c->orph_dnext) {
757 orph = c->orph_dnext;
758 c->orph_dnext = orph->dnext;
759 list_del(&orph->list);
760 kfree(orph);
761 }
762
763 while (!list_empty(&c->orph_list)) {
764 orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
765 list_del(&orph->list);
766 kfree(orph);
767 dbg_err("orphan list not empty at unmount");
768 }
769
770 vfree(c->orph_buf);
771 c->orph_buf = NULL;
772}
773
774/**
775 * free_buds - free per-bud objects.
776 * @c: UBIFS file-system description object
777 */
778static void free_buds(struct ubifs_info *c)
779{
780 struct rb_node *this = c->buds.rb_node;
781 struct ubifs_bud *bud;
782
783 while (this) {
784 if (this->rb_left)
785 this = this->rb_left;
786 else if (this->rb_right)
787 this = this->rb_right;
788 else {
789 bud = rb_entry(this, struct ubifs_bud, rb);
790 this = rb_parent(this);
791 if (this) {
792 if (this->rb_left == &bud->rb)
793 this->rb_left = NULL;
794 else
795 this->rb_right = NULL;
796 }
797 kfree(bud);
798 }
799 }
800}
801
802/**
803 * check_volume_empty - check if the UBI volume is empty.
804 * @c: UBIFS file-system description object
805 *
806 * This function checks if the UBIFS volume is empty by looking if its LEBs are
807 * mapped or not. The result of checking is stored in the @c->empty variable.
808 * Returns zero in case of success and a negative error code in case of
809 * failure.
810 */
811static int check_volume_empty(struct ubifs_info *c)
812{
813 int lnum, err;
814
815 c->empty = 1;
816 for (lnum = 0; lnum < c->leb_cnt; lnum++) {
817 err = ubi_is_mapped(c->ubi, lnum);
818 if (unlikely(err < 0))
819 return err;
820 if (err == 1) {
821 c->empty = 0;
822 break;
823 }
824
825 cond_resched();
826 }
827
828 return 0;
829}
830
831/*
832 * UBIFS mount options.
833 *
834 * Opt_fast_unmount: do not run a journal commit before un-mounting
835 * Opt_norm_unmount: run a journal commit before un-mounting
836 * Opt_err: just end of array marker
837 */
838enum {
839 Opt_fast_unmount,
840 Opt_norm_unmount,
841 Opt_err,
842};
843
844static match_table_t tokens = {
845 {Opt_fast_unmount, "fast_unmount"},
846 {Opt_norm_unmount, "norm_unmount"},
847 {Opt_err, NULL},
848};
849
850/**
851 * ubifs_parse_options - parse mount parameters.
852 * @c: UBIFS file-system description object
853 * @options: parameters to parse
854 * @is_remount: non-zero if this is FS re-mount
855 *
856 * This function parses UBIFS mount options and returns zero in case success
857 * and a negative error code in case of failure.
858 */
859static int ubifs_parse_options(struct ubifs_info *c, char *options,
860 int is_remount)
861{
862 char *p;
863 substring_t args[MAX_OPT_ARGS];
864
865 if (!options)
866 return 0;
867
868 while ((p = strsep(&options, ","))) {
869 int token;
870
871 if (!*p)
872 continue;
873
874 token = match_token(p, tokens, args);
875 switch (token) {
876 case Opt_fast_unmount:
877 c->mount_opts.unmount_mode = 2;
878 c->fast_unmount = 1;
879 break;
880 case Opt_norm_unmount:
881 c->mount_opts.unmount_mode = 1;
882 c->fast_unmount = 0;
883 break;
884 default:
885 ubifs_err("unrecognized mount option \"%s\" "
886 "or missing value", p);
887 return -EINVAL;
888 }
889 }
890
891 return 0;
892}
893
894/**
895 * destroy_journal - destroy journal data structures.
896 * @c: UBIFS file-system description object
897 *
898 * This function destroys journal data structures including those that may have
899 * been created by recovery functions.
900 */
901static void destroy_journal(struct ubifs_info *c)
902{
903 while (!list_empty(&c->unclean_leb_list)) {
904 struct ubifs_unclean_leb *ucleb;
905
906 ucleb = list_entry(c->unclean_leb_list.next,
907 struct ubifs_unclean_leb, list);
908 list_del(&ucleb->list);
909 kfree(ucleb);
910 }
911 while (!list_empty(&c->old_buds)) {
912 struct ubifs_bud *bud;
913
914 bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
915 list_del(&bud->list);
916 kfree(bud);
917 }
918 ubifs_destroy_idx_gc(c);
919 ubifs_destroy_size_tree(c);
920 ubifs_tnc_close(c);
921 free_buds(c);
922}
923
924/**
925 * mount_ubifs - mount UBIFS file-system.
926 * @c: UBIFS file-system description object
927 *
928 * This function mounts UBIFS file system. Returns zero in case of success and
929 * a negative error code in case of failure.
930 *
931 * Note, the function does not de-allocate resources it it fails half way
932 * through, and the caller has to do this instead.
933 */
934static int mount_ubifs(struct ubifs_info *c)
935{
936 struct super_block *sb = c->vfs_sb;
937 int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
938 long long x;
939 size_t sz;
940
941 err = init_constants_early(c);
942 if (err)
943 return err;
944
945#ifdef CONFIG_UBIFS_FS_DEBUG
946 c->dbg_buf = vmalloc(c->leb_size);
947 if (!c->dbg_buf)
948 return -ENOMEM;
949#endif
950
951 err = check_volume_empty(c);
952 if (err)
953 goto out_free;
954
955 if (c->empty && (mounted_read_only || c->ro_media)) {
956 /*
957 * This UBI volume is empty, and read-only, or the file system
958 * is mounted read-only - we cannot format it.
959 */
960 ubifs_err("can't format empty UBI volume: read-only %s",
961 c->ro_media ? "UBI volume" : "mount");
962 err = -EROFS;
963 goto out_free;
964 }
965
966 if (c->ro_media && !mounted_read_only) {
967 ubifs_err("cannot mount read-write - read-only media");
968 err = -EROFS;
969 goto out_free;
970 }
971
972 /*
973 * The requirement for the buffer is that it should fit indexing B-tree
974 * height amount of integers. We assume the height if the TNC tree will
975 * never exceed 64.
976 */
977 err = -ENOMEM;
978 c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
979 if (!c->bottom_up_buf)
980 goto out_free;
981
982 c->sbuf = vmalloc(c->leb_size);
983 if (!c->sbuf)
984 goto out_free;
985
986 if (!mounted_read_only) {
987 c->ileb_buf = vmalloc(c->leb_size);
988 if (!c->ileb_buf)
989 goto out_free;
990 }
991
992 err = ubifs_read_superblock(c);
993 if (err)
994 goto out_free;
995
996 /*
997 * Make sure the compressor which is set as the default on in the
998 * superblock was actually compiled in.
999 */
1000 if (!ubifs_compr_present(c->default_compr)) {
1001 ubifs_warn("'%s' compressor is set by superblock, but not "
1002 "compiled in", ubifs_compr_name(c->default_compr));
1003 c->default_compr = UBIFS_COMPR_NONE;
1004 }
1005
1006 dbg_failure_mode_registration(c);
1007
1008 err = init_constants_late(c);
1009 if (err)
1010 goto out_dereg;
1011
1012 sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
1013 sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
1014 c->cbuf = kmalloc(sz, GFP_NOFS);
1015 if (!c->cbuf) {
1016 err = -ENOMEM;
1017 goto out_dereg;
1018 }
1019
1020 if (!mounted_read_only) {
1021 err = alloc_wbufs(c);
1022 if (err)
1023 goto out_cbuf;
1024
1025 /* Create background thread */
1026 sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num,
1027 c->vi.vol_id);
1028 c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
1029 if (!c->bgt)
1030 c->bgt = ERR_PTR(-EINVAL);
1031 if (IS_ERR(c->bgt)) {
1032 err = PTR_ERR(c->bgt);
1033 c->bgt = NULL;
1034 ubifs_err("cannot spawn \"%s\", error %d",
1035 c->bgt_name, err);
1036 goto out_wbufs;
1037 }
1038 wake_up_process(c->bgt);
1039 }
1040
1041 err = ubifs_read_master(c);
1042 if (err)
1043 goto out_master;
1044
1045 if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
1046 ubifs_msg("recovery needed");
1047 c->need_recovery = 1;
1048 if (!mounted_read_only) {
1049 err = ubifs_recover_inl_heads(c, c->sbuf);
1050 if (err)
1051 goto out_master;
1052 }
1053 } else if (!mounted_read_only) {
1054 /*
1055 * Set the "dirty" flag so that if we reboot uncleanly we
1056 * will notice this immediately on the next mount.
1057 */
1058 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1059 err = ubifs_write_master(c);
1060 if (err)
1061 goto out_master;
1062 }
1063
1064 err = ubifs_lpt_init(c, 1, !mounted_read_only);
1065 if (err)
1066 goto out_lpt;
1067
1068 err = dbg_check_idx_size(c, c->old_idx_sz);
1069 if (err)
1070 goto out_lpt;
1071
1072 err = ubifs_replay_journal(c);
1073 if (err)
1074 goto out_journal;
1075
1076 err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
1077 if (err)
1078 goto out_orphans;
1079
1080 if (!mounted_read_only) {
1081 int lnum;
1082
1083 /* Check for enough free space */
1084 if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
1085 ubifs_err("insufficient available space");
1086 err = -EINVAL;
1087 goto out_orphans;
1088 }
1089
1090 /* Check for enough log space */
1091 lnum = c->lhead_lnum + 1;
1092 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1093 lnum = UBIFS_LOG_LNUM;
1094 if (lnum == c->ltail_lnum) {
1095 err = ubifs_consolidate_log(c);
1096 if (err)
1097 goto out_orphans;
1098 }
1099
1100 if (c->need_recovery) {
1101 err = ubifs_recover_size(c);
1102 if (err)
1103 goto out_orphans;
1104 err = ubifs_rcvry_gc_commit(c);
1105 } else
1106 err = take_gc_lnum(c);
1107 if (err)
1108 goto out_orphans;
1109
1110 err = dbg_check_lprops(c);
1111 if (err)
1112 goto out_orphans;
1113 } else if (c->need_recovery) {
1114 err = ubifs_recover_size(c);
1115 if (err)
1116 goto out_orphans;
1117 }
1118
1119 spin_lock(&ubifs_infos_lock);
1120 list_add_tail(&c->infos_list, &ubifs_infos);
1121 spin_unlock(&ubifs_infos_lock);
1122
1123 if (c->need_recovery) {
1124 if (mounted_read_only)
1125 ubifs_msg("recovery deferred");
1126 else {
1127 c->need_recovery = 0;
1128 ubifs_msg("recovery completed");
1129 }
1130 }
1131
1132 err = dbg_check_filesystem(c);
1133 if (err)
1134 goto out_infos;
1135
Artem Bityutskiyce769ca2008-07-18 12:54:21 +03001136 ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
1137 c->vi.ubi_num, c->vi.vol_id, c->vi.name);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001138 if (mounted_read_only)
1139 ubifs_msg("mounted read-only");
1140 x = (long long)c->main_lebs * c->leb_size;
1141 ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
1142 x, x >> 10, x >> 20, c->main_lebs);
1143 x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
1144 ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d LEBs)",
1145 x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
1146 ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
1147 ubifs_msg("media format %d, latest format %d",
1148 c->fmt_version, UBIFS_FORMAT_VERSION);
1149
1150 dbg_msg("compiled on: " __DATE__ " at " __TIME__);
1151 dbg_msg("min. I/O unit size: %d bytes", c->min_io_size);
1152 dbg_msg("LEB size: %d bytes (%d KiB)",
1153 c->leb_size, c->leb_size / 1024);
1154 dbg_msg("data journal heads: %d",
1155 c->jhead_cnt - NONDATA_JHEADS_CNT);
1156 dbg_msg("UUID: %02X%02X%02X%02X-%02X%02X"
1157 "-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
1158 c->uuid[0], c->uuid[1], c->uuid[2], c->uuid[3],
1159 c->uuid[4], c->uuid[5], c->uuid[6], c->uuid[7],
1160 c->uuid[8], c->uuid[9], c->uuid[10], c->uuid[11],
1161 c->uuid[12], c->uuid[13], c->uuid[14], c->uuid[15]);
1162 dbg_msg("fast unmount: %d", c->fast_unmount);
1163 dbg_msg("big_lpt %d", c->big_lpt);
1164 dbg_msg("log LEBs: %d (%d - %d)",
1165 c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
1166 dbg_msg("LPT area LEBs: %d (%d - %d)",
1167 c->lpt_lebs, c->lpt_first, c->lpt_last);
1168 dbg_msg("orphan area LEBs: %d (%d - %d)",
1169 c->orph_lebs, c->orph_first, c->orph_last);
1170 dbg_msg("main area LEBs: %d (%d - %d)",
1171 c->main_lebs, c->main_first, c->leb_cnt - 1);
1172 dbg_msg("index LEBs: %d", c->lst.idx_lebs);
1173 dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)",
1174 c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20);
1175 dbg_msg("key hash type: %d", c->key_hash_type);
1176 dbg_msg("tree fanout: %d", c->fanout);
1177 dbg_msg("reserved GC LEB: %d", c->gc_lnum);
1178 dbg_msg("first main LEB: %d", c->main_first);
1179 dbg_msg("dead watermark: %d", c->dead_wm);
1180 dbg_msg("dark watermark: %d", c->dark_wm);
1181 x = (long long)c->main_lebs * c->dark_wm;
1182 dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)",
1183 x, x >> 10, x >> 20);
1184 dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)",
1185 c->max_bud_bytes, c->max_bud_bytes >> 10,
1186 c->max_bud_bytes >> 20);
1187 dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
1188 c->bg_bud_bytes, c->bg_bud_bytes >> 10,
1189 c->bg_bud_bytes >> 20);
1190 dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)",
1191 c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
1192 dbg_msg("max. seq. number: %llu", c->max_sqnum);
1193 dbg_msg("commit number: %llu", c->cmt_no);
1194
1195 return 0;
1196
1197out_infos:
1198 spin_lock(&ubifs_infos_lock);
1199 list_del(&c->infos_list);
1200 spin_unlock(&ubifs_infos_lock);
1201out_orphans:
1202 free_orphans(c);
1203out_journal:
1204 destroy_journal(c);
1205out_lpt:
1206 ubifs_lpt_free(c, 0);
1207out_master:
1208 kfree(c->mst_node);
1209 kfree(c->rcvrd_mst_node);
1210 if (c->bgt)
1211 kthread_stop(c->bgt);
1212out_wbufs:
1213 free_wbufs(c);
1214out_cbuf:
1215 kfree(c->cbuf);
1216out_dereg:
1217 dbg_failure_mode_deregistration(c);
1218out_free:
1219 vfree(c->ileb_buf);
1220 vfree(c->sbuf);
1221 kfree(c->bottom_up_buf);
1222 UBIFS_DBG(vfree(c->dbg_buf));
1223 return err;
1224}
1225
1226/**
1227 * ubifs_umount - un-mount UBIFS file-system.
1228 * @c: UBIFS file-system description object
1229 *
1230 * Note, this function is called to free allocated resourced when un-mounting,
1231 * as well as free resources when an error occurred while we were half way
1232 * through mounting (error path cleanup function). So it has to make sure the
1233 * resource was actually allocated before freeing it.
1234 */
1235static void ubifs_umount(struct ubifs_info *c)
1236{
1237 dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
1238 c->vi.vol_id);
1239
1240 spin_lock(&ubifs_infos_lock);
1241 list_del(&c->infos_list);
1242 spin_unlock(&ubifs_infos_lock);
1243
1244 if (c->bgt)
1245 kthread_stop(c->bgt);
1246
1247 destroy_journal(c);
1248 free_wbufs(c);
1249 free_orphans(c);
1250 ubifs_lpt_free(c, 0);
1251
1252 kfree(c->cbuf);
1253 kfree(c->rcvrd_mst_node);
1254 kfree(c->mst_node);
1255 vfree(c->sbuf);
1256 kfree(c->bottom_up_buf);
1257 UBIFS_DBG(vfree(c->dbg_buf));
1258 vfree(c->ileb_buf);
1259 dbg_failure_mode_deregistration(c);
1260}
1261
1262/**
1263 * ubifs_remount_rw - re-mount in read-write mode.
1264 * @c: UBIFS file-system description object
1265 *
1266 * UBIFS avoids allocating many unnecessary resources when mounted in read-only
1267 * mode. This function allocates the needed resources and re-mounts UBIFS in
1268 * read-write mode.
1269 */
1270static int ubifs_remount_rw(struct ubifs_info *c)
1271{
1272 int err, lnum;
1273
1274 if (c->ro_media)
1275 return -EINVAL;
1276
1277 mutex_lock(&c->umount_mutex);
1278 c->remounting_rw = 1;
1279
1280 /* Check for enough free space */
1281 if (ubifs_calc_available(c, c->min_idx_lebs) <= 0) {
1282 ubifs_err("insufficient available space");
1283 err = -EINVAL;
1284 goto out;
1285 }
1286
1287 if (c->old_leb_cnt != c->leb_cnt) {
1288 struct ubifs_sb_node *sup;
1289
1290 sup = ubifs_read_sb_node(c);
1291 if (IS_ERR(sup)) {
1292 err = PTR_ERR(sup);
1293 goto out;
1294 }
1295 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
1296 err = ubifs_write_sb_node(c, sup);
1297 if (err)
1298 goto out;
1299 }
1300
1301 if (c->need_recovery) {
1302 ubifs_msg("completing deferred recovery");
1303 err = ubifs_write_rcvrd_mst_node(c);
1304 if (err)
1305 goto out;
1306 err = ubifs_recover_size(c);
1307 if (err)
1308 goto out;
1309 err = ubifs_clean_lebs(c, c->sbuf);
1310 if (err)
1311 goto out;
1312 err = ubifs_recover_inl_heads(c, c->sbuf);
1313 if (err)
1314 goto out;
1315 }
1316
1317 if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
1318 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1319 err = ubifs_write_master(c);
1320 if (err)
1321 goto out;
1322 }
1323
1324 c->ileb_buf = vmalloc(c->leb_size);
1325 if (!c->ileb_buf) {
1326 err = -ENOMEM;
1327 goto out;
1328 }
1329
1330 err = ubifs_lpt_init(c, 0, 1);
1331 if (err)
1332 goto out;
1333
1334 err = alloc_wbufs(c);
1335 if (err)
1336 goto out;
1337
1338 ubifs_create_buds_lists(c);
1339
1340 /* Create background thread */
1341 c->bgt = kthread_create(ubifs_bg_thread, c, c->bgt_name);
1342 if (!c->bgt)
1343 c->bgt = ERR_PTR(-EINVAL);
1344 if (IS_ERR(c->bgt)) {
1345 err = PTR_ERR(c->bgt);
1346 c->bgt = NULL;
1347 ubifs_err("cannot spawn \"%s\", error %d",
1348 c->bgt_name, err);
1349 return err;
1350 }
1351 wake_up_process(c->bgt);
1352
1353 c->orph_buf = vmalloc(c->leb_size);
1354 if (!c->orph_buf)
1355 return -ENOMEM;
1356
1357 /* Check for enough log space */
1358 lnum = c->lhead_lnum + 1;
1359 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1360 lnum = UBIFS_LOG_LNUM;
1361 if (lnum == c->ltail_lnum) {
1362 err = ubifs_consolidate_log(c);
1363 if (err)
1364 goto out;
1365 }
1366
1367 if (c->need_recovery)
1368 err = ubifs_rcvry_gc_commit(c);
1369 else
1370 err = take_gc_lnum(c);
1371 if (err)
1372 goto out;
1373
1374 if (c->need_recovery) {
1375 c->need_recovery = 0;
1376 ubifs_msg("deferred recovery completed");
1377 }
1378
1379 dbg_gen("re-mounted read-write");
1380 c->vfs_sb->s_flags &= ~MS_RDONLY;
1381 c->remounting_rw = 0;
1382 mutex_unlock(&c->umount_mutex);
1383 return 0;
1384
1385out:
1386 vfree(c->orph_buf);
1387 c->orph_buf = NULL;
1388 if (c->bgt) {
1389 kthread_stop(c->bgt);
1390 c->bgt = NULL;
1391 }
1392 free_wbufs(c);
1393 vfree(c->ileb_buf);
1394 c->ileb_buf = NULL;
1395 ubifs_lpt_free(c, 1);
1396 c->remounting_rw = 0;
1397 mutex_unlock(&c->umount_mutex);
1398 return err;
1399}
1400
1401/**
1402 * commit_on_unmount - commit the journal when un-mounting.
1403 * @c: UBIFS file-system description object
1404 *
1405 * This function is called during un-mounting and it commits the journal unless
1406 * the "fast unmount" mode is enabled. It also avoids committing the journal if
1407 * it contains too few data.
1408 *
1409 * Sometimes recovery requires the journal to be committed at least once, and
1410 * this function takes care about this.
1411 */
1412static void commit_on_unmount(struct ubifs_info *c)
1413{
1414 if (!c->fast_unmount) {
1415 long long bud_bytes;
1416
1417 spin_lock(&c->buds_lock);
1418 bud_bytes = c->bud_bytes;
1419 spin_unlock(&c->buds_lock);
1420 if (bud_bytes > c->leb_size)
1421 ubifs_run_commit(c);
1422 }
1423}
1424
1425/**
1426 * ubifs_remount_ro - re-mount in read-only mode.
1427 * @c: UBIFS file-system description object
1428 *
1429 * We rely on VFS to have stopped writing. Possibly the background thread could
1430 * be running a commit, however kthread_stop will wait in that case.
1431 */
1432static void ubifs_remount_ro(struct ubifs_info *c)
1433{
1434 int i, err;
1435
1436 ubifs_assert(!c->need_recovery);
1437 commit_on_unmount(c);
1438
1439 mutex_lock(&c->umount_mutex);
1440 if (c->bgt) {
1441 kthread_stop(c->bgt);
1442 c->bgt = NULL;
1443 }
1444
1445 for (i = 0; i < c->jhead_cnt; i++) {
1446 ubifs_wbuf_sync(&c->jheads[i].wbuf);
1447 del_timer_sync(&c->jheads[i].wbuf.timer);
1448 }
1449
1450 if (!c->ro_media) {
1451 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
1452 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
1453 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
1454 err = ubifs_write_master(c);
1455 if (err)
1456 ubifs_ro_mode(c, err);
1457 }
1458
1459 ubifs_destroy_idx_gc(c);
1460 free_wbufs(c);
1461 vfree(c->orph_buf);
1462 c->orph_buf = NULL;
1463 vfree(c->ileb_buf);
1464 c->ileb_buf = NULL;
1465 ubifs_lpt_free(c, 1);
1466 mutex_unlock(&c->umount_mutex);
1467}
1468
1469static void ubifs_put_super(struct super_block *sb)
1470{
1471 int i;
1472 struct ubifs_info *c = sb->s_fs_info;
1473
1474 ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num,
1475 c->vi.vol_id);
1476 /*
1477 * The following asserts are only valid if there has not been a failure
1478 * of the media. For example, there will be dirty inodes if we failed
1479 * to write them back because of I/O errors.
1480 */
1481 ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0);
1482 ubifs_assert(c->budg_idx_growth == 0);
Artem Bityutskiy7d32c2b2008-07-18 18:54:29 +03001483 ubifs_assert(c->budg_dd_growth == 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001484 ubifs_assert(c->budg_data_growth == 0);
1485
1486 /*
1487 * The 'c->umount_lock' prevents races between UBIFS memory shrinker
1488 * and file system un-mount. Namely, it prevents the shrinker from
1489 * picking this superblock for shrinking - it will be just skipped if
1490 * the mutex is locked.
1491 */
1492 mutex_lock(&c->umount_mutex);
1493 if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
1494 /*
1495 * First of all kill the background thread to make sure it does
1496 * not interfere with un-mounting and freeing resources.
1497 */
1498 if (c->bgt) {
1499 kthread_stop(c->bgt);
1500 c->bgt = NULL;
1501 }
1502
1503 /* Synchronize write-buffers */
1504 if (c->jheads)
1505 for (i = 0; i < c->jhead_cnt; i++) {
1506 ubifs_wbuf_sync(&c->jheads[i].wbuf);
1507 del_timer_sync(&c->jheads[i].wbuf.timer);
1508 }
1509
1510 /*
1511 * On fatal errors c->ro_media is set to 1, in which case we do
1512 * not write the master node.
1513 */
1514 if (!c->ro_media) {
1515 /*
1516 * We are being cleanly unmounted which means the
1517 * orphans were killed - indicate this in the master
1518 * node. Also save the reserved GC LEB number.
1519 */
1520 int err;
1521
1522 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
1523 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
1524 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
1525 err = ubifs_write_master(c);
1526 if (err)
1527 /*
1528 * Recovery will attempt to fix the master area
1529 * next mount, so we just print a message and
1530 * continue to unmount normally.
1531 */
1532 ubifs_err("failed to write master node, "
1533 "error %d", err);
1534 }
1535 }
1536
1537 ubifs_umount(c);
1538 bdi_destroy(&c->bdi);
1539 ubi_close_volume(c->ubi);
1540 mutex_unlock(&c->umount_mutex);
1541 kfree(c);
1542}
1543
1544static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
1545{
1546 int err;
1547 struct ubifs_info *c = sb->s_fs_info;
1548
1549 dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
1550
1551 err = ubifs_parse_options(c, data, 1);
1552 if (err) {
1553 ubifs_err("invalid or unknown remount parameter");
1554 return err;
1555 }
1556 if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
1557 err = ubifs_remount_rw(c);
1558 if (err)
1559 return err;
1560 } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY))
1561 ubifs_remount_ro(c);
1562
1563 return 0;
1564}
1565
1566struct super_operations ubifs_super_operations = {
1567 .alloc_inode = ubifs_alloc_inode,
1568 .destroy_inode = ubifs_destroy_inode,
1569 .put_super = ubifs_put_super,
1570 .write_inode = ubifs_write_inode,
1571 .delete_inode = ubifs_delete_inode,
1572 .statfs = ubifs_statfs,
1573 .dirty_inode = ubifs_dirty_inode,
1574 .remount_fs = ubifs_remount_fs,
1575 .show_options = ubifs_show_options,
1576 .sync_fs = ubifs_sync_fs,
1577};
1578
1579/**
1580 * open_ubi - parse UBI device name string and open the UBI device.
1581 * @name: UBI volume name
1582 * @mode: UBI volume open mode
1583 *
1584 * There are several ways to specify UBI volumes when mounting UBIFS:
1585 * o ubiX_Y - UBI device number X, volume Y;
1586 * o ubiY - UBI device number 0, volume Y;
1587 * o ubiX:NAME - mount UBI device X, volume with name NAME;
1588 * o ubi:NAME - mount UBI device 0, volume with name NAME.
1589 *
1590 * Alternative '!' separator may be used instead of ':' (because some shells
1591 * like busybox may interpret ':' as an NFS host name separator). This function
1592 * returns ubi volume object in case of success and a negative error code in
1593 * case of failure.
1594 */
1595static struct ubi_volume_desc *open_ubi(const char *name, int mode)
1596{
1597 int dev, vol;
1598 char *endptr;
1599
1600 if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
1601 return ERR_PTR(-EINVAL);
1602
1603 /* ubi:NAME method */
1604 if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
1605 return ubi_open_volume_nm(0, name + 4, mode);
1606
1607 if (!isdigit(name[3]))
1608 return ERR_PTR(-EINVAL);
1609
1610 dev = simple_strtoul(name + 3, &endptr, 0);
1611
1612 /* ubiY method */
1613 if (*endptr == '\0')
1614 return ubi_open_volume(0, dev, mode);
1615
1616 /* ubiX_Y method */
1617 if (*endptr == '_' && isdigit(endptr[1])) {
1618 vol = simple_strtoul(endptr + 1, &endptr, 0);
1619 if (*endptr != '\0')
1620 return ERR_PTR(-EINVAL);
1621 return ubi_open_volume(dev, vol, mode);
1622 }
1623
1624 /* ubiX:NAME method */
1625 if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
1626 return ubi_open_volume_nm(dev, ++endptr, mode);
1627
1628 return ERR_PTR(-EINVAL);
1629}
1630
1631static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
1632{
1633 struct ubi_volume_desc *ubi = sb->s_fs_info;
1634 struct ubifs_info *c;
1635 struct inode *root;
1636 int err;
1637
1638 c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
1639 if (!c)
1640 return -ENOMEM;
1641
1642 spin_lock_init(&c->cnt_lock);
1643 spin_lock_init(&c->cs_lock);
1644 spin_lock_init(&c->buds_lock);
1645 spin_lock_init(&c->space_lock);
1646 spin_lock_init(&c->orphan_lock);
1647 init_rwsem(&c->commit_sem);
1648 mutex_init(&c->lp_mutex);
1649 mutex_init(&c->tnc_mutex);
1650 mutex_init(&c->log_mutex);
1651 mutex_init(&c->mst_mutex);
1652 mutex_init(&c->umount_mutex);
1653 init_waitqueue_head(&c->cmt_wq);
1654 c->buds = RB_ROOT;
1655 c->old_idx = RB_ROOT;
1656 c->size_tree = RB_ROOT;
1657 c->orph_tree = RB_ROOT;
1658 INIT_LIST_HEAD(&c->infos_list);
1659 INIT_LIST_HEAD(&c->idx_gc);
1660 INIT_LIST_HEAD(&c->replay_list);
1661 INIT_LIST_HEAD(&c->replay_buds);
1662 INIT_LIST_HEAD(&c->uncat_list);
1663 INIT_LIST_HEAD(&c->empty_list);
1664 INIT_LIST_HEAD(&c->freeable_list);
1665 INIT_LIST_HEAD(&c->frdi_idx_list);
1666 INIT_LIST_HEAD(&c->unclean_leb_list);
1667 INIT_LIST_HEAD(&c->old_buds);
1668 INIT_LIST_HEAD(&c->orph_list);
1669 INIT_LIST_HEAD(&c->orph_new);
1670
1671 c->highest_inum = UBIFS_FIRST_INO;
1672 get_random_bytes(&c->vfs_gen, sizeof(int));
1673 c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
1674
1675 ubi_get_volume_info(ubi, &c->vi);
1676 ubi_get_device_info(c->vi.ubi_num, &c->di);
1677
1678 /* Re-open the UBI device in read-write mode */
1679 c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
1680 if (IS_ERR(c->ubi)) {
1681 err = PTR_ERR(c->ubi);
1682 goto out_free;
1683 }
1684
1685 /*
1686 * UBIFS provids 'backing_dev_info' in order to disable readahead. For
1687 * UBIFS, I/O is not deferred, it is done immediately in readpage,
1688 * which means the user would have to wait not just for their own I/O
1689 * but the readahead I/O as well i.e. completely pointless.
1690 *
1691 * Read-ahead will be disabled because @c->bdi.ra_pages is 0.
1692 */
1693 c->bdi.capabilities = BDI_CAP_MAP_COPY;
1694 c->bdi.unplug_io_fn = default_unplug_io_fn;
1695 err = bdi_init(&c->bdi);
1696 if (err)
1697 goto out_close;
1698
1699 err = ubifs_parse_options(c, data, 0);
1700 if (err)
1701 goto out_bdi;
1702
1703 c->vfs_sb = sb;
1704
1705 sb->s_fs_info = c;
1706 sb->s_magic = UBIFS_SUPER_MAGIC;
1707 sb->s_blocksize = UBIFS_BLOCK_SIZE;
1708 sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
1709 sb->s_dev = c->vi.cdev;
1710 sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
1711 if (c->max_inode_sz > MAX_LFS_FILESIZE)
1712 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
1713 sb->s_op = &ubifs_super_operations;
1714
1715 mutex_lock(&c->umount_mutex);
1716 err = mount_ubifs(c);
1717 if (err) {
1718 ubifs_assert(err < 0);
1719 goto out_unlock;
1720 }
1721
1722 /* Read the root inode */
1723 root = ubifs_iget(sb, UBIFS_ROOT_INO);
1724 if (IS_ERR(root)) {
1725 err = PTR_ERR(root);
1726 goto out_umount;
1727 }
1728
1729 sb->s_root = d_alloc_root(root);
1730 if (!sb->s_root)
1731 goto out_iput;
1732
1733 mutex_unlock(&c->umount_mutex);
1734
1735 return 0;
1736
1737out_iput:
1738 iput(root);
1739out_umount:
1740 ubifs_umount(c);
1741out_unlock:
1742 mutex_unlock(&c->umount_mutex);
1743out_bdi:
1744 bdi_destroy(&c->bdi);
1745out_close:
1746 ubi_close_volume(c->ubi);
1747out_free:
1748 kfree(c);
1749 return err;
1750}
1751
1752static int sb_test(struct super_block *sb, void *data)
1753{
1754 dev_t *dev = data;
1755
1756 return sb->s_dev == *dev;
1757}
1758
1759static int sb_set(struct super_block *sb, void *data)
1760{
1761 dev_t *dev = data;
1762
1763 sb->s_dev = *dev;
1764 return 0;
1765}
1766
1767static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
1768 const char *name, void *data, struct vfsmount *mnt)
1769{
1770 struct ubi_volume_desc *ubi;
1771 struct ubi_volume_info vi;
1772 struct super_block *sb;
1773 int err;
1774
1775 dbg_gen("name %s, flags %#x", name, flags);
1776
1777 /*
1778 * Get UBI device number and volume ID. Mount it read-only so far
1779 * because this might be a new mount point, and UBI allows only one
1780 * read-write user at a time.
1781 */
1782 ubi = open_ubi(name, UBI_READONLY);
1783 if (IS_ERR(ubi)) {
1784 ubifs_err("cannot open \"%s\", error %d",
1785 name, (int)PTR_ERR(ubi));
1786 return PTR_ERR(ubi);
1787 }
1788 ubi_get_volume_info(ubi, &vi);
1789
1790 dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id);
1791
1792 sb = sget(fs_type, &sb_test, &sb_set, &vi.cdev);
1793 if (IS_ERR(sb)) {
1794 err = PTR_ERR(sb);
1795 goto out_close;
1796 }
1797
1798 if (sb->s_root) {
1799 /* A new mount point for already mounted UBIFS */
1800 dbg_gen("this ubi volume is already mounted");
1801 if ((flags ^ sb->s_flags) & MS_RDONLY) {
1802 err = -EBUSY;
1803 goto out_deact;
1804 }
1805 } else {
1806 sb->s_flags = flags;
1807 /*
1808 * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is
1809 * replaced by 'c'.
1810 */
1811 sb->s_fs_info = ubi;
1812 err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
1813 if (err)
1814 goto out_deact;
1815 /* We do not support atime */
1816 sb->s_flags |= MS_ACTIVE | MS_NOATIME;
1817 }
1818
1819 /* 'fill_super()' opens ubi again so we must close it here */
1820 ubi_close_volume(ubi);
1821
1822 return simple_set_mnt(mnt, sb);
1823
1824out_deact:
1825 up_write(&sb->s_umount);
1826 deactivate_super(sb);
1827out_close:
1828 ubi_close_volume(ubi);
1829 return err;
1830}
1831
1832static void ubifs_kill_sb(struct super_block *sb)
1833{
1834 struct ubifs_info *c = sb->s_fs_info;
1835
1836 /*
1837 * We do 'commit_on_unmount()' here instead of 'ubifs_put_super()'
1838 * in order to be outside BKL.
1839 */
1840 if (sb->s_root && !(sb->s_flags & MS_RDONLY))
1841 commit_on_unmount(c);
1842 /* The un-mount routine is actually done in put_super() */
1843 generic_shutdown_super(sb);
1844}
1845
1846static struct file_system_type ubifs_fs_type = {
1847 .name = "ubifs",
1848 .owner = THIS_MODULE,
1849 .get_sb = ubifs_get_sb,
1850 .kill_sb = ubifs_kill_sb
1851};
1852
1853/*
1854 * Inode slab cache constructor.
1855 */
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001856static void inode_slab_ctor(void *obj)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001857{
1858 struct ubifs_inode *ui = obj;
1859 inode_init_once(&ui->vfs_inode);
1860}
1861
1862static int __init ubifs_init(void)
1863{
1864 int err;
1865
1866 BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
1867
1868 /* Make sure node sizes are 8-byte aligned */
1869 BUILD_BUG_ON(UBIFS_CH_SZ & 7);
1870 BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7);
1871 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
1872 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
1873 BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
1874 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
1875 BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7);
1876 BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7);
1877 BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7);
1878 BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7);
1879 BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
1880
1881 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
1882 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
1883 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
1884 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7);
1885 BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7);
1886 BUILD_BUG_ON(MIN_WRITE_SZ & 7);
1887
1888 /* Check min. node size */
1889 BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ);
1890 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
1891 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
1892 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
1893
1894 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
1895 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
1896 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
1897 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ);
1898
1899 /* Defined node sizes */
1900 BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096);
1901 BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
1902 BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
1903 BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
1904
1905 /*
1906 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
1907 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
1908 */
1909 if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
1910 ubifs_err("VFS page cache size is %u bytes, but UBIFS requires"
1911 " at least 4096 bytes",
1912 (unsigned int)PAGE_CACHE_SIZE);
1913 return -EINVAL;
1914 }
1915
1916 err = register_filesystem(&ubifs_fs_type);
1917 if (err) {
1918 ubifs_err("cannot register file system, error %d", err);
1919 return err;
1920 }
1921
1922 err = -ENOMEM;
1923 ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
1924 sizeof(struct ubifs_inode), 0,
1925 SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
1926 &inode_slab_ctor);
1927 if (!ubifs_inode_slab)
1928 goto out_reg;
1929
1930 register_shrinker(&ubifs_shrinker_info);
1931
1932 err = ubifs_compressors_init();
1933 if (err)
1934 goto out_compr;
1935
1936 return 0;
1937
1938out_compr:
1939 unregister_shrinker(&ubifs_shrinker_info);
1940 kmem_cache_destroy(ubifs_inode_slab);
1941out_reg:
1942 unregister_filesystem(&ubifs_fs_type);
1943 return err;
1944}
1945/* late_initcall to let compressors initialize first */
1946late_initcall(ubifs_init);
1947
1948static void __exit ubifs_exit(void)
1949{
1950 ubifs_assert(list_empty(&ubifs_infos));
1951 ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
1952
1953 ubifs_compressors_exit();
1954 unregister_shrinker(&ubifs_shrinker_info);
1955 kmem_cache_destroy(ubifs_inode_slab);
1956 unregister_filesystem(&ubifs_fs_type);
1957}
1958module_exit(ubifs_exit);
1959
1960MODULE_LICENSE("GPL");
1961MODULE_VERSION(__stringify(UBIFS_VERSION));
1962MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
1963MODULE_DESCRIPTION("UBIFS - UBI File System");