blob: 43f9d19a6f3313ec3df7f358138e153703d4895b [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>
Artem Bityutskiy1e517642008-07-14 19:08:37 +030033#include <linux/kthread.h>
34#include <linux/parser.h>
35#include <linux/seq_file.h>
36#include <linux/mount.h>
Artem Bityutskiy4d61db42008-12-18 14:06:51 +020037#include <linux/math64.h>
Artem Bityutskiy304d4272008-12-28 08:04:17 +020038#include <linux/writeback.h>
Artem Bityutskiy1e517642008-07-14 19:08:37 +030039#include "ubifs.h"
40
Artem Bityutskiy39ce81c2008-11-18 18:09:49 +020041/*
42 * Maximum amount of memory we may 'kmalloc()' without worrying that we are
43 * allocating too much.
44 */
45#define UBIFS_KMALLOC_OK (128*1024)
46
Artem Bityutskiy1e517642008-07-14 19:08:37 +030047/* Slab cache for UBIFS inodes */
48struct kmem_cache *ubifs_inode_slab;
49
50/* UBIFS TNC shrinker description */
51static struct shrinker ubifs_shrinker_info = {
52 .shrink = ubifs_shrinker,
53 .seeks = DEFAULT_SEEKS,
54};
55
56/**
57 * validate_inode - validate inode.
58 * @c: UBIFS file-system description object
59 * @inode: the inode to validate
60 *
61 * This is a helper function for 'ubifs_iget()' which validates various fields
62 * of a newly built inode to make sure they contain sane values and prevent
63 * possible vulnerabilities. Returns zero if the inode is all right and
64 * a non-zero error code if not.
65 */
66static int validate_inode(struct ubifs_info *c, const struct inode *inode)
67{
68 int err;
69 const struct ubifs_inode *ui = ubifs_inode(inode);
70
71 if (inode->i_size > c->max_inode_sz) {
72 ubifs_err("inode is too large (%lld)",
73 (long long)inode->i_size);
74 return 1;
75 }
76
77 if (ui->compr_type < 0 || ui->compr_type >= UBIFS_COMPR_TYPES_CNT) {
78 ubifs_err("unknown compression type %d", ui->compr_type);
79 return 2;
80 }
81
82 if (ui->xattr_names + ui->xattr_cnt > XATTR_LIST_MAX)
83 return 3;
84
85 if (ui->data_len < 0 || ui->data_len > UBIFS_MAX_INO_DATA)
86 return 4;
87
88 if (ui->xattr && (inode->i_mode & S_IFMT) != S_IFREG)
89 return 5;
90
91 if (!ubifs_compr_present(ui->compr_type)) {
92 ubifs_warn("inode %lu uses '%s' compression, but it was not "
93 "compiled in", inode->i_ino,
94 ubifs_compr_name(ui->compr_type));
95 }
96
97 err = dbg_check_dir_size(c, inode);
98 return err;
99}
100
101struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
102{
103 int err;
104 union ubifs_key key;
105 struct ubifs_ino_node *ino;
106 struct ubifs_info *c = sb->s_fs_info;
107 struct inode *inode;
108 struct ubifs_inode *ui;
109
110 dbg_gen("inode %lu", inum);
111
112 inode = iget_locked(sb, inum);
113 if (!inode)
114 return ERR_PTR(-ENOMEM);
115 if (!(inode->i_state & I_NEW))
116 return inode;
117 ui = ubifs_inode(inode);
118
119 ino = kmalloc(UBIFS_MAX_INO_NODE_SZ, GFP_NOFS);
120 if (!ino) {
121 err = -ENOMEM;
122 goto out;
123 }
124
125 ino_key_init(c, &key, inode->i_ino);
126
127 err = ubifs_tnc_lookup(c, &key, ino);
128 if (err)
129 goto out_ino;
130
131 inode->i_flags |= (S_NOCMTIME | S_NOATIME);
132 inode->i_nlink = le32_to_cpu(ino->nlink);
133 inode->i_uid = le32_to_cpu(ino->uid);
134 inode->i_gid = le32_to_cpu(ino->gid);
135 inode->i_atime.tv_sec = (int64_t)le64_to_cpu(ino->atime_sec);
136 inode->i_atime.tv_nsec = le32_to_cpu(ino->atime_nsec);
137 inode->i_mtime.tv_sec = (int64_t)le64_to_cpu(ino->mtime_sec);
138 inode->i_mtime.tv_nsec = le32_to_cpu(ino->mtime_nsec);
139 inode->i_ctime.tv_sec = (int64_t)le64_to_cpu(ino->ctime_sec);
140 inode->i_ctime.tv_nsec = le32_to_cpu(ino->ctime_nsec);
141 inode->i_mode = le32_to_cpu(ino->mode);
142 inode->i_size = le64_to_cpu(ino->size);
143
144 ui->data_len = le32_to_cpu(ino->data_len);
145 ui->flags = le32_to_cpu(ino->flags);
146 ui->compr_type = le16_to_cpu(ino->compr_type);
147 ui->creat_sqnum = le64_to_cpu(ino->creat_sqnum);
148 ui->xattr_cnt = le32_to_cpu(ino->xattr_cnt);
149 ui->xattr_size = le32_to_cpu(ino->xattr_size);
150 ui->xattr_names = le32_to_cpu(ino->xattr_names);
151 ui->synced_i_size = ui->ui_size = inode->i_size;
152
153 ui->xattr = (ui->flags & UBIFS_XATTR_FL) ? 1 : 0;
154
155 err = validate_inode(c, inode);
156 if (err)
157 goto out_invalid;
158
Artem Bityutskiy0a883a02008-08-13 14:13:26 +0300159 /* Disable read-ahead */
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300160 inode->i_mapping->backing_dev_info = &c->bdi;
161
162 switch (inode->i_mode & S_IFMT) {
163 case S_IFREG:
164 inode->i_mapping->a_ops = &ubifs_file_address_operations;
165 inode->i_op = &ubifs_file_inode_operations;
166 inode->i_fop = &ubifs_file_operations;
167 if (ui->xattr) {
168 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
169 if (!ui->data) {
170 err = -ENOMEM;
171 goto out_ino;
172 }
173 memcpy(ui->data, ino->data, ui->data_len);
174 ((char *)ui->data)[ui->data_len] = '\0';
175 } else if (ui->data_len != 0) {
176 err = 10;
177 goto out_invalid;
178 }
179 break;
180 case S_IFDIR:
181 inode->i_op = &ubifs_dir_inode_operations;
182 inode->i_fop = &ubifs_dir_operations;
183 if (ui->data_len != 0) {
184 err = 11;
185 goto out_invalid;
186 }
187 break;
188 case S_IFLNK:
189 inode->i_op = &ubifs_symlink_inode_operations;
190 if (ui->data_len <= 0 || ui->data_len > UBIFS_MAX_INO_DATA) {
191 err = 12;
192 goto out_invalid;
193 }
194 ui->data = kmalloc(ui->data_len + 1, GFP_NOFS);
195 if (!ui->data) {
196 err = -ENOMEM;
197 goto out_ino;
198 }
199 memcpy(ui->data, ino->data, ui->data_len);
200 ((char *)ui->data)[ui->data_len] = '\0';
201 break;
202 case S_IFBLK:
203 case S_IFCHR:
204 {
205 dev_t rdev;
206 union ubifs_dev_desc *dev;
207
208 ui->data = kmalloc(sizeof(union ubifs_dev_desc), GFP_NOFS);
209 if (!ui->data) {
210 err = -ENOMEM;
211 goto out_ino;
212 }
213
214 dev = (union ubifs_dev_desc *)ino->data;
215 if (ui->data_len == sizeof(dev->new))
216 rdev = new_decode_dev(le32_to_cpu(dev->new));
217 else if (ui->data_len == sizeof(dev->huge))
218 rdev = huge_decode_dev(le64_to_cpu(dev->huge));
219 else {
220 err = 13;
221 goto out_invalid;
222 }
223 memcpy(ui->data, ino->data, ui->data_len);
224 inode->i_op = &ubifs_file_inode_operations;
225 init_special_inode(inode, inode->i_mode, rdev);
226 break;
227 }
228 case S_IFSOCK:
229 case S_IFIFO:
230 inode->i_op = &ubifs_file_inode_operations;
231 init_special_inode(inode, inode->i_mode, 0);
232 if (ui->data_len != 0) {
233 err = 14;
234 goto out_invalid;
235 }
236 break;
237 default:
238 err = 15;
239 goto out_invalid;
240 }
241
242 kfree(ino);
243 ubifs_set_inode_flags(inode);
244 unlock_new_inode(inode);
245 return inode;
246
247out_invalid:
248 ubifs_err("inode %lu validation failed, error %d", inode->i_ino, err);
249 dbg_dump_node(c, ino);
250 dbg_dump_inode(c, inode);
251 err = -EINVAL;
252out_ino:
253 kfree(ino);
254out:
255 ubifs_err("failed to read inode %lu, error %d", inode->i_ino, err);
256 iget_failed(inode);
257 return ERR_PTR(err);
258}
259
260static struct inode *ubifs_alloc_inode(struct super_block *sb)
261{
262 struct ubifs_inode *ui;
263
264 ui = kmem_cache_alloc(ubifs_inode_slab, GFP_NOFS);
265 if (!ui)
266 return NULL;
267
268 memset((void *)ui + sizeof(struct inode), 0,
269 sizeof(struct ubifs_inode) - sizeof(struct inode));
270 mutex_init(&ui->ui_mutex);
271 spin_lock_init(&ui->ui_lock);
272 return &ui->vfs_inode;
273};
274
275static void ubifs_destroy_inode(struct inode *inode)
276{
277 struct ubifs_inode *ui = ubifs_inode(inode);
278
279 kfree(ui->data);
280 kmem_cache_free(ubifs_inode_slab, inode);
281}
282
283/*
284 * Note, Linux write-back code calls this without 'i_mutex'.
285 */
286static int ubifs_write_inode(struct inode *inode, int wait)
287{
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300288 int err = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300289 struct ubifs_info *c = inode->i_sb->s_fs_info;
290 struct ubifs_inode *ui = ubifs_inode(inode);
291
292 ubifs_assert(!ui->xattr);
293 if (is_bad_inode(inode))
294 return 0;
295
296 mutex_lock(&ui->ui_mutex);
297 /*
298 * Due to races between write-back forced by budgeting
299 * (see 'sync_some_inodes()') and pdflush write-back, the inode may
300 * have already been synchronized, do not do this again. This might
301 * also happen if it was synchronized in an VFS operation, e.g.
302 * 'ubifs_link()'.
303 */
304 if (!ui->dirty) {
305 mutex_unlock(&ui->ui_mutex);
306 return 0;
307 }
308
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300309 /*
310 * As an optimization, do not write orphan inodes to the media just
311 * because this is not needed.
312 */
313 dbg_gen("inode %lu, mode %#x, nlink %u",
314 inode->i_ino, (int)inode->i_mode, inode->i_nlink);
315 if (inode->i_nlink) {
Artem Bityutskiy1f286812008-07-22 12:06:13 +0300316 err = ubifs_jnl_write_inode(c, inode);
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300317 if (err)
318 ubifs_err("can't write inode %lu, error %d",
319 inode->i_ino, err);
Artem Bityutskiye3c3efc2009-08-27 16:34:19 +0300320 else
321 err = dbg_check_inode_size(c, inode, ui->ui_size);
Artem Bityutskiyfbfa6c82008-07-22 11:52:52 +0300322 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300323
324 ui->dirty = 0;
325 mutex_unlock(&ui->ui_mutex);
326 ubifs_release_dirty_inode_budget(c, ui);
327 return err;
328}
329
330static void ubifs_delete_inode(struct inode *inode)
331{
332 int err;
333 struct ubifs_info *c = inode->i_sb->s_fs_info;
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300334 struct ubifs_inode *ui = ubifs_inode(inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300335
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300336 if (ui->xattr)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300337 /*
338 * Extended attribute inode deletions are fully handled in
339 * 'ubifs_removexattr()'. These inodes are special and have
340 * limited usage, so there is nothing to do here.
341 */
342 goto out;
343
Artem Bityutskiy7d32c2b2008-07-18 18:54:29 +0300344 dbg_gen("inode %lu, mode %#x", inode->i_ino, (int)inode->i_mode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300345 ubifs_assert(!atomic_read(&inode->i_count));
346 ubifs_assert(inode->i_nlink == 0);
347
348 truncate_inode_pages(&inode->i_data, 0);
349 if (is_bad_inode(inode))
350 goto out;
351
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300352 ui->ui_size = inode->i_size = 0;
Artem Bityutskiyde94eb52008-07-22 13:06:20 +0300353 err = ubifs_jnl_delete_inode(c, inode);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300354 if (err)
355 /*
356 * Worst case we have a lost orphan inode wasting space, so a
Artem Bityutskiy0a883a02008-08-13 14:13:26 +0300357 * simple error message is OK here.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300358 */
Artem Bityutskiyde94eb52008-07-22 13:06:20 +0300359 ubifs_err("can't delete inode %lu, error %d",
360 inode->i_ino, err);
361
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300362out:
Artem Bityutskiy1e0f3582008-07-21 10:59:53 +0300363 if (ui->dirty)
364 ubifs_release_dirty_inode_budget(c, ui);
Adrian Hunter6d6cb0d2009-04-08 14:07:57 +0200365 else {
366 /* We've deleted something - clean the "no space" flags */
367 c->nospace = c->nospace_rp = 0;
368 smp_wmb();
369 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300370 clear_inode(inode);
371}
372
373static void ubifs_dirty_inode(struct inode *inode)
374{
375 struct ubifs_inode *ui = ubifs_inode(inode);
376
377 ubifs_assert(mutex_is_locked(&ui->ui_mutex));
378 if (!ui->dirty) {
379 ui->dirty = 1;
380 dbg_gen("inode %lu", inode->i_ino);
381 }
382}
383
384static int ubifs_statfs(struct dentry *dentry, struct kstatfs *buf)
385{
386 struct ubifs_info *c = dentry->d_sb->s_fs_info;
387 unsigned long long free;
Artem Bityutskiy7c7cbad2008-09-03 14:16:42 +0300388 __le32 *uuid = (__le32 *)c->uuid;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300389
Artem Bityutskiy7dad1812008-08-25 18:58:19 +0300390 free = ubifs_get_free_space(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300391 dbg_gen("free space %lld bytes (%lld blocks)",
392 free, free >> UBIFS_BLOCK_SHIFT);
393
394 buf->f_type = UBIFS_SUPER_MAGIC;
395 buf->f_bsize = UBIFS_BLOCK_SIZE;
396 buf->f_blocks = c->block_cnt;
397 buf->f_bfree = free >> UBIFS_BLOCK_SHIFT;
398 if (free > c->report_rp_size)
399 buf->f_bavail = (free - c->report_rp_size) >> UBIFS_BLOCK_SHIFT;
400 else
401 buf->f_bavail = 0;
402 buf->f_files = 0;
403 buf->f_ffree = 0;
404 buf->f_namelen = UBIFS_MAX_NLEN;
Artem Bityutskiy7c7cbad2008-09-03 14:16:42 +0300405 buf->f_fsid.val[0] = le32_to_cpu(uuid[0]) ^ le32_to_cpu(uuid[2]);
406 buf->f_fsid.val[1] = le32_to_cpu(uuid[1]) ^ le32_to_cpu(uuid[3]);
Artem Bityutskiyb4978e92009-01-23 18:23:03 +0200407 ubifs_assert(buf->f_bfree <= c->block_cnt);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300408 return 0;
409}
410
411static int ubifs_show_options(struct seq_file *s, struct vfsmount *mnt)
412{
413 struct ubifs_info *c = mnt->mnt_sb->s_fs_info;
414
415 if (c->mount_opts.unmount_mode == 2)
416 seq_printf(s, ",fast_unmount");
417 else if (c->mount_opts.unmount_mode == 1)
418 seq_printf(s, ",norm_unmount");
419
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300420 if (c->mount_opts.bulk_read == 2)
421 seq_printf(s, ",bulk_read");
422 else if (c->mount_opts.bulk_read == 1)
423 seq_printf(s, ",no_bulk_read");
424
Adrian Hunter2953e732008-09-04 16:26:00 +0300425 if (c->mount_opts.chk_data_crc == 2)
426 seq_printf(s, ",chk_data_crc");
427 else if (c->mount_opts.chk_data_crc == 1)
428 seq_printf(s, ",no_chk_data_crc");
429
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200430 if (c->mount_opts.override_compr) {
Hunter Adrianfcabb342009-03-18 12:29:39 +0100431 seq_printf(s, ",compr=%s",
432 ubifs_compr_name(c->mount_opts.compr_type));
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200433 }
434
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300435 return 0;
436}
437
438static int ubifs_sync_fs(struct super_block *sb, int wait)
439{
Artem Bityutskiyf1038302008-12-28 08:16:32 +0200440 int i, err;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300441 struct ubifs_info *c = sb->s_fs_info;
Artem Bityutskiy304d4272008-12-28 08:04:17 +0200442
Artem Bityutskiye8ea1752009-01-06 14:40:23 -0800443 /*
Artem Bityutskiydedb0d42009-01-09 21:02:37 +0200444 * Zero @wait is just an advisory thing to help the file system shove
445 * lots of data into the queues, and there will be the second
Artem Bityutskiye8ea1752009-01-06 14:40:23 -0800446 * '->sync_fs()' call, with non-zero @wait.
447 */
Artem Bityutskiydedb0d42009-01-09 21:02:37 +0200448 if (!wait)
449 return 0;
Artem Bityutskiye8ea1752009-01-06 14:40:23 -0800450
Artem Bityutskiyf1038302008-12-28 08:16:32 +0200451 /*
Adrian Hunter3eb14292009-01-29 11:17:24 +0200452 * Synchronize write buffers, because 'ubifs_run_commit()' does not
453 * do this if it waits for an already running commit.
454 */
455 for (i = 0; i < c->jhead_cnt; i++) {
456 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
457 if (err)
458 return err;
459 }
460
Artem Bityutskiy887ee172009-07-20 17:56:19 +0300461 /*
462 * Strictly speaking, it is not necessary to commit the journal here,
463 * synchronizing write-buffers would be enough. But committing makes
464 * UBIFS free space predictions much more accurate, so we want to let
465 * the user be able to get more accurate results of 'statfs()' after
466 * they synchronize the file system.
467 */
Artem Bityutskiyf1038302008-12-28 08:16:32 +0200468 err = ubifs_run_commit(c);
469 if (err)
470 return err;
Artem Bityutskiy403e12a2008-09-09 12:31:37 +0300471
Artem Bityutskiycb5c6a22008-12-28 08:18:43 +0200472 return ubi_sync(c->vi.ubi_num);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300473}
474
475/**
476 * init_constants_early - initialize UBIFS constants.
477 * @c: UBIFS file-system description object
478 *
479 * This function initialize UBIFS constants which do not need the superblock to
480 * be read. It also checks that the UBI volume satisfies basic UBIFS
481 * requirements. Returns zero in case of success and a negative error code in
482 * case of failure.
483 */
484static int init_constants_early(struct ubifs_info *c)
485{
486 if (c->vi.corrupted) {
487 ubifs_warn("UBI volume is corrupted - read-only mode");
488 c->ro_media = 1;
489 }
490
491 if (c->di.ro_mode) {
492 ubifs_msg("read-only UBI device");
493 c->ro_media = 1;
494 }
495
496 if (c->vi.vol_type == UBI_STATIC_VOLUME) {
497 ubifs_msg("static UBI volume - read-only mode");
498 c->ro_media = 1;
499 }
500
501 c->leb_cnt = c->vi.size;
502 c->leb_size = c->vi.usable_leb_size;
503 c->half_leb_size = c->leb_size / 2;
504 c->min_io_size = c->di.min_io_size;
505 c->min_io_shift = fls(c->min_io_size) - 1;
506
507 if (c->leb_size < UBIFS_MIN_LEB_SZ) {
508 ubifs_err("too small LEBs (%d bytes), min. is %d bytes",
509 c->leb_size, UBIFS_MIN_LEB_SZ);
510 return -EINVAL;
511 }
512
513 if (c->leb_cnt < UBIFS_MIN_LEB_CNT) {
514 ubifs_err("too few LEBs (%d), min. is %d",
515 c->leb_cnt, UBIFS_MIN_LEB_CNT);
516 return -EINVAL;
517 }
518
519 if (!is_power_of_2(c->min_io_size)) {
520 ubifs_err("bad min. I/O size %d", c->min_io_size);
521 return -EINVAL;
522 }
523
524 /*
525 * UBIFS aligns all node to 8-byte boundary, so to make function in
526 * io.c simpler, assume minimum I/O unit size to be 8 bytes if it is
527 * less than 8.
528 */
529 if (c->min_io_size < 8) {
530 c->min_io_size = 8;
531 c->min_io_shift = 3;
532 }
533
534 c->ref_node_alsz = ALIGN(UBIFS_REF_NODE_SZ, c->min_io_size);
535 c->mst_node_alsz = ALIGN(UBIFS_MST_NODE_SZ, c->min_io_size);
536
537 /*
538 * Initialize node length ranges which are mostly needed for node
539 * length validation.
540 */
541 c->ranges[UBIFS_PAD_NODE].len = UBIFS_PAD_NODE_SZ;
542 c->ranges[UBIFS_SB_NODE].len = UBIFS_SB_NODE_SZ;
543 c->ranges[UBIFS_MST_NODE].len = UBIFS_MST_NODE_SZ;
544 c->ranges[UBIFS_REF_NODE].len = UBIFS_REF_NODE_SZ;
545 c->ranges[UBIFS_TRUN_NODE].len = UBIFS_TRUN_NODE_SZ;
546 c->ranges[UBIFS_CS_NODE].len = UBIFS_CS_NODE_SZ;
547
548 c->ranges[UBIFS_INO_NODE].min_len = UBIFS_INO_NODE_SZ;
549 c->ranges[UBIFS_INO_NODE].max_len = UBIFS_MAX_INO_NODE_SZ;
550 c->ranges[UBIFS_ORPH_NODE].min_len =
551 UBIFS_ORPH_NODE_SZ + sizeof(__le64);
552 c->ranges[UBIFS_ORPH_NODE].max_len = c->leb_size;
553 c->ranges[UBIFS_DENT_NODE].min_len = UBIFS_DENT_NODE_SZ;
554 c->ranges[UBIFS_DENT_NODE].max_len = UBIFS_MAX_DENT_NODE_SZ;
555 c->ranges[UBIFS_XENT_NODE].min_len = UBIFS_XENT_NODE_SZ;
556 c->ranges[UBIFS_XENT_NODE].max_len = UBIFS_MAX_XENT_NODE_SZ;
557 c->ranges[UBIFS_DATA_NODE].min_len = UBIFS_DATA_NODE_SZ;
558 c->ranges[UBIFS_DATA_NODE].max_len = UBIFS_MAX_DATA_NODE_SZ;
559 /*
560 * Minimum indexing node size is amended later when superblock is
561 * read and the key length is known.
562 */
563 c->ranges[UBIFS_IDX_NODE].min_len = UBIFS_IDX_NODE_SZ + UBIFS_BRANCH_SZ;
564 /*
565 * Maximum indexing node size is amended later when superblock is
566 * read and the fanout is known.
567 */
568 c->ranges[UBIFS_IDX_NODE].max_len = INT_MAX;
569
570 /*
Artem Bityutskiy70782022009-01-19 19:57:27 +0200571 * Initialize dead and dark LEB space watermarks. See gc.c for comments
572 * about these values.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300573 */
574 c->dead_wm = ALIGN(MIN_WRITE_SZ, c->min_io_size);
575 c->dark_wm = ALIGN(UBIFS_MAX_NODE_SZ, c->min_io_size);
576
Artem Bityutskiy9bbb5722008-08-22 18:23:22 +0300577 /*
578 * Calculate how many bytes would be wasted at the end of LEB if it was
579 * fully filled with data nodes of maximum size. This is used in
580 * calculations when reporting free space.
581 */
582 c->leb_overhead = c->leb_size % UBIFS_MAX_DATA_NODE_SZ;
Artem Bityutskiy39ce81c2008-11-18 18:09:49 +0200583
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300584 /* Buffer size for bulk-reads */
Artem Bityutskiy6c0c42c2008-11-18 20:20:05 +0200585 c->max_bu_buf_len = UBIFS_MAX_BULK_READ * UBIFS_MAX_DATA_NODE_SZ;
586 if (c->max_bu_buf_len > c->leb_size)
587 c->max_bu_buf_len = c->leb_size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300588 return 0;
589}
590
591/**
592 * bud_wbuf_callback - bud LEB write-buffer synchronization call-back.
593 * @c: UBIFS file-system description object
594 * @lnum: LEB the write-buffer was synchronized to
595 * @free: how many free bytes left in this LEB
596 * @pad: how many bytes were padded
597 *
598 * This is a callback function which is called by the I/O unit when the
599 * write-buffer is synchronized. We need this to correctly maintain space
600 * accounting in bud logical eraseblocks. This function returns zero in case of
601 * success and a negative error code in case of failure.
602 *
603 * This function actually belongs to the journal, but we keep it here because
604 * we want to keep it static.
605 */
606static int bud_wbuf_callback(struct ubifs_info *c, int lnum, int free, int pad)
607{
608 return ubifs_update_one_lp(c, lnum, free, pad, 0, 0);
609}
610
611/*
Artem Bityutskiy79807d02008-12-27 19:18:00 +0200612 * init_constants_sb - initialize UBIFS constants.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300613 * @c: UBIFS file-system description object
614 *
615 * This is a helper function which initializes various UBIFS constants after
616 * the superblock has been read. It also checks various UBIFS parameters and
617 * makes sure they are all right. Returns zero in case of success and a
618 * negative error code in case of failure.
619 */
Artem Bityutskiy79807d02008-12-27 19:18:00 +0200620static int init_constants_sb(struct ubifs_info *c)
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300621{
622 int tmp, err;
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200623 long long tmp64;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300624
625 c->main_bytes = (long long)c->main_lebs * c->leb_size;
626 c->max_znode_sz = sizeof(struct ubifs_znode) +
627 c->fanout * sizeof(struct ubifs_zbranch);
628
629 tmp = ubifs_idx_node_sz(c, 1);
630 c->ranges[UBIFS_IDX_NODE].min_len = tmp;
631 c->min_idx_node_sz = ALIGN(tmp, 8);
632
633 tmp = ubifs_idx_node_sz(c, c->fanout);
634 c->ranges[UBIFS_IDX_NODE].max_len = tmp;
635 c->max_idx_node_sz = ALIGN(tmp, 8);
636
637 /* Make sure LEB size is large enough to fit full commit */
638 tmp = UBIFS_CS_NODE_SZ + UBIFS_REF_NODE_SZ * c->jhead_cnt;
639 tmp = ALIGN(tmp, c->min_io_size);
640 if (tmp > c->leb_size) {
641 dbg_err("too small LEB size %d, at least %d needed",
642 c->leb_size, tmp);
643 return -EINVAL;
644 }
645
646 /*
647 * Make sure that the log is large enough to fit reference nodes for
648 * all buds plus one reserved LEB.
649 */
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200650 tmp64 = c->max_bud_bytes + c->leb_size - 1;
651 c->max_bud_cnt = div_u64(tmp64, c->leb_size);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300652 tmp = (c->ref_node_alsz * c->max_bud_cnt + c->leb_size - 1);
653 tmp /= c->leb_size;
654 tmp += 1;
655 if (c->log_lebs < tmp) {
656 dbg_err("too small log %d LEBs, required min. %d LEBs",
657 c->log_lebs, tmp);
658 return -EINVAL;
659 }
660
661 /*
662 * When budgeting we assume worst-case scenarios when the pages are not
663 * be compressed and direntries are of the maximum size.
664 *
665 * Note, data, which may be stored in inodes is budgeted separately, so
666 * it is not included into 'c->inode_budget'.
667 */
668 c->page_budget = UBIFS_MAX_DATA_NODE_SZ * UBIFS_BLOCKS_PER_PAGE;
669 c->inode_budget = UBIFS_INO_NODE_SZ;
670 c->dent_budget = UBIFS_MAX_DENT_NODE_SZ;
671
672 /*
673 * When the amount of flash space used by buds becomes
674 * 'c->max_bud_bytes', UBIFS just blocks all writers and starts commit.
675 * The writers are unblocked when the commit is finished. To avoid
676 * writers to be blocked UBIFS initiates background commit in advance,
677 * when number of bud bytes becomes above the limit defined below.
678 */
679 c->bg_bud_bytes = (c->max_bud_bytes * 13) >> 4;
680
681 /*
682 * Ensure minimum journal size. All the bytes in the journal heads are
683 * considered to be used, when calculating the current journal usage.
684 * Consequently, if the journal is too small, UBIFS will treat it as
685 * always full.
686 */
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200687 tmp64 = (long long)(c->jhead_cnt + 1) * c->leb_size + 1;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300688 if (c->bg_bud_bytes < tmp64)
689 c->bg_bud_bytes = tmp64;
690 if (c->max_bud_bytes < tmp64 + c->leb_size)
691 c->max_bud_bytes = tmp64 + c->leb_size;
692
693 err = ubifs_calc_lpt_geom(c);
694 if (err)
695 return err;
696
Artem Bityutskiyfb1cd012009-03-16 09:56:57 +0200697 /* Initialize effective LEB size used in budgeting calculations */
698 c->idx_leb_size = c->leb_size - c->max_idx_node_sz;
Artem Bityutskiy79807d02008-12-27 19:18:00 +0200699 return 0;
700}
701
702/*
703 * init_constants_master - initialize UBIFS constants.
704 * @c: UBIFS file-system description object
705 *
706 * This is a helper function which initializes various UBIFS constants after
707 * the master node has been read. It also checks various UBIFS parameters and
708 * makes sure they are all right.
709 */
710static void init_constants_master(struct ubifs_info *c)
711{
712 long long tmp64;
713
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300714 c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
Artem Bityutskiyfb1cd012009-03-16 09:56:57 +0200715 c->report_rp_size = ubifs_reported_space(c, c->rp_size);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300716
717 /*
718 * Calculate total amount of FS blocks. This number is not used
719 * internally because it does not make much sense for UBIFS, but it is
720 * necessary to report something for the 'statfs()' call.
721 *
Artem Bityutskiy7dad1812008-08-25 18:58:19 +0300722 * Subtract the LEB reserved for GC, the LEB which is reserved for
Artem Bityutskiyaf14a1a2008-12-19 19:26:29 +0200723 * deletions, minimum LEBs for the index, and assume only one journal
724 * head is available.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300725 */
Artem Bityutskiyaf14a1a2008-12-19 19:26:29 +0200726 tmp64 = c->main_lebs - 1 - 1 - MIN_INDEX_LEBS - c->jhead_cnt + 1;
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200727 tmp64 *= (long long)c->leb_size - c->leb_overhead;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300728 tmp64 = ubifs_reported_space(c, tmp64);
729 c->block_cnt = tmp64 >> UBIFS_BLOCK_SHIFT;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300730}
731
732/**
733 * take_gc_lnum - reserve GC LEB.
734 * @c: UBIFS file-system description object
735 *
Artem Bityutskiyb4978e92009-01-23 18:23:03 +0200736 * This function ensures that the LEB reserved for garbage collection is marked
737 * as "taken" in lprops. We also have to set free space to LEB size and dirty
738 * space to zero, because lprops may contain out-of-date information if the
739 * file-system was un-mounted before it has been committed. This function
740 * returns zero in case of success and a negative error code in case of
741 * failure.
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300742 */
743static int take_gc_lnum(struct ubifs_info *c)
744{
745 int err;
746
747 if (c->gc_lnum == -1) {
748 ubifs_err("no LEB for GC");
749 return -EINVAL;
750 }
751
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300752 /* And we have to tell lprops that this LEB is taken */
753 err = ubifs_change_one_lp(c, c->gc_lnum, c->leb_size, 0,
754 LPROPS_TAKEN, 0, 0);
755 return err;
756}
757
758/**
759 * alloc_wbufs - allocate write-buffers.
760 * @c: UBIFS file-system description object
761 *
762 * This helper function allocates and initializes UBIFS write-buffers. Returns
763 * zero in case of success and %-ENOMEM in case of failure.
764 */
765static int alloc_wbufs(struct ubifs_info *c)
766{
767 int i, err;
768
769 c->jheads = kzalloc(c->jhead_cnt * sizeof(struct ubifs_jhead),
770 GFP_KERNEL);
771 if (!c->jheads)
772 return -ENOMEM;
773
774 /* Initialize journal heads */
775 for (i = 0; i < c->jhead_cnt; i++) {
776 INIT_LIST_HEAD(&c->jheads[i].buds_list);
777 err = ubifs_wbuf_init(c, &c->jheads[i].wbuf);
778 if (err)
779 return err;
780
781 c->jheads[i].wbuf.sync_callback = &bud_wbuf_callback;
782 c->jheads[i].wbuf.jhead = i;
783 }
784
785 c->jheads[BASEHD].wbuf.dtype = UBI_SHORTTERM;
786 /*
787 * Garbage Collector head likely contains long-term data and
788 * does not need to be synchronized by timer.
789 */
790 c->jheads[GCHD].wbuf.dtype = UBI_LONGTERM;
Artem Bityutskiy0b335b92009-06-23 12:30:43 +0300791 c->jheads[GCHD].wbuf.no_timer = 1;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300792
793 return 0;
794}
795
796/**
797 * free_wbufs - free write-buffers.
798 * @c: UBIFS file-system description object
799 */
800static void free_wbufs(struct ubifs_info *c)
801{
802 int i;
803
804 if (c->jheads) {
805 for (i = 0; i < c->jhead_cnt; i++) {
806 kfree(c->jheads[i].wbuf.buf);
807 kfree(c->jheads[i].wbuf.inodes);
808 }
809 kfree(c->jheads);
810 c->jheads = NULL;
811 }
812}
813
814/**
815 * free_orphans - free orphans.
816 * @c: UBIFS file-system description object
817 */
818static void free_orphans(struct ubifs_info *c)
819{
820 struct ubifs_orphan *orph;
821
822 while (c->orph_dnext) {
823 orph = c->orph_dnext;
824 c->orph_dnext = orph->dnext;
825 list_del(&orph->list);
826 kfree(orph);
827 }
828
829 while (!list_empty(&c->orph_list)) {
830 orph = list_entry(c->orph_list.next, struct ubifs_orphan, list);
831 list_del(&orph->list);
832 kfree(orph);
833 dbg_err("orphan list not empty at unmount");
834 }
835
836 vfree(c->orph_buf);
837 c->orph_buf = NULL;
838}
839
840/**
841 * free_buds - free per-bud objects.
842 * @c: UBIFS file-system description object
843 */
844static void free_buds(struct ubifs_info *c)
845{
846 struct rb_node *this = c->buds.rb_node;
847 struct ubifs_bud *bud;
848
849 while (this) {
850 if (this->rb_left)
851 this = this->rb_left;
852 else if (this->rb_right)
853 this = this->rb_right;
854 else {
855 bud = rb_entry(this, struct ubifs_bud, rb);
856 this = rb_parent(this);
857 if (this) {
858 if (this->rb_left == &bud->rb)
859 this->rb_left = NULL;
860 else
861 this->rb_right = NULL;
862 }
863 kfree(bud);
864 }
865 }
866}
867
868/**
869 * check_volume_empty - check if the UBI volume is empty.
870 * @c: UBIFS file-system description object
871 *
872 * This function checks if the UBIFS volume is empty by looking if its LEBs are
873 * mapped or not. The result of checking is stored in the @c->empty variable.
874 * Returns zero in case of success and a negative error code in case of
875 * failure.
876 */
877static int check_volume_empty(struct ubifs_info *c)
878{
879 int lnum, err;
880
881 c->empty = 1;
882 for (lnum = 0; lnum < c->leb_cnt; lnum++) {
883 err = ubi_is_mapped(c->ubi, lnum);
884 if (unlikely(err < 0))
885 return err;
886 if (err == 1) {
887 c->empty = 0;
888 break;
889 }
890
891 cond_resched();
892 }
893
894 return 0;
895}
896
897/*
898 * UBIFS mount options.
899 *
900 * Opt_fast_unmount: do not run a journal commit before un-mounting
901 * Opt_norm_unmount: run a journal commit before un-mounting
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300902 * Opt_bulk_read: enable bulk-reads
903 * Opt_no_bulk_read: disable bulk-reads
Adrian Hunter2953e732008-09-04 16:26:00 +0300904 * Opt_chk_data_crc: check CRCs when reading data nodes
905 * Opt_no_chk_data_crc: do not check CRCs when reading data nodes
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200906 * Opt_override_compr: override default compressor
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300907 * Opt_err: just end of array marker
908 */
909enum {
910 Opt_fast_unmount,
911 Opt_norm_unmount,
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300912 Opt_bulk_read,
913 Opt_no_bulk_read,
Adrian Hunter2953e732008-09-04 16:26:00 +0300914 Opt_chk_data_crc,
915 Opt_no_chk_data_crc,
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200916 Opt_override_compr,
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300917 Opt_err,
918};
919
Steven Whitehousea447c092008-10-13 10:46:57 +0100920static const match_table_t tokens = {
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300921 {Opt_fast_unmount, "fast_unmount"},
922 {Opt_norm_unmount, "norm_unmount"},
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300923 {Opt_bulk_read, "bulk_read"},
924 {Opt_no_bulk_read, "no_bulk_read"},
Adrian Hunter2953e732008-09-04 16:26:00 +0300925 {Opt_chk_data_crc, "chk_data_crc"},
926 {Opt_no_chk_data_crc, "no_chk_data_crc"},
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200927 {Opt_override_compr, "compr=%s"},
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300928 {Opt_err, NULL},
929};
930
931/**
Artem Bityutskiy8379ea32009-05-29 12:34:52 +0300932 * parse_standard_option - parse a standard mount option.
933 * @option: the option to parse
934 *
935 * Normally, standard mount options like "sync" are passed to file-systems as
936 * flags. However, when a "rootflags=" kernel boot parameter is used, they may
937 * be present in the options string. This function tries to deal with this
938 * situation and parse standard options. Returns 0 if the option was not
939 * recognized, and the corresponding integer flag if it was.
940 *
941 * UBIFS is only interested in the "sync" option, so do not check for anything
942 * else.
943 */
944static int parse_standard_option(const char *option)
945{
946 ubifs_msg("parse %s", option);
947 if (!strcmp(option, "sync"))
948 return MS_SYNCHRONOUS;
949 return 0;
950}
951
952/**
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300953 * ubifs_parse_options - parse mount parameters.
954 * @c: UBIFS file-system description object
955 * @options: parameters to parse
956 * @is_remount: non-zero if this is FS re-mount
957 *
958 * This function parses UBIFS mount options and returns zero in case success
959 * and a negative error code in case of failure.
960 */
961static int ubifs_parse_options(struct ubifs_info *c, char *options,
962 int is_remount)
963{
964 char *p;
965 substring_t args[MAX_OPT_ARGS];
966
967 if (!options)
968 return 0;
969
970 while ((p = strsep(&options, ","))) {
971 int token;
972
973 if (!*p)
974 continue;
975
976 token = match_token(p, tokens, args);
977 switch (token) {
Artem Bityutskiy27ad2792009-01-29 16:34:30 +0200978 /*
979 * %Opt_fast_unmount and %Opt_norm_unmount options are ignored.
Artem Bityutskiycb54ef82009-06-23 20:30:32 +0300980 * We accept them in order to be backward-compatible. But this
Artem Bityutskiy27ad2792009-01-29 16:34:30 +0200981 * should be removed at some point.
982 */
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300983 case Opt_fast_unmount:
984 c->mount_opts.unmount_mode = 2;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300985 break;
986 case Opt_norm_unmount:
987 c->mount_opts.unmount_mode = 1;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300988 break;
Adrian Hunter4793e7c2008-09-02 16:29:46 +0300989 case Opt_bulk_read:
990 c->mount_opts.bulk_read = 2;
991 c->bulk_read = 1;
992 break;
993 case Opt_no_bulk_read:
994 c->mount_opts.bulk_read = 1;
995 c->bulk_read = 0;
996 break;
Adrian Hunter2953e732008-09-04 16:26:00 +0300997 case Opt_chk_data_crc:
998 c->mount_opts.chk_data_crc = 2;
999 c->no_chk_data_crc = 0;
1000 break;
1001 case Opt_no_chk_data_crc:
1002 c->mount_opts.chk_data_crc = 1;
1003 c->no_chk_data_crc = 1;
1004 break;
Artem Bityutskiy553dea42008-11-01 14:57:49 +02001005 case Opt_override_compr:
1006 {
1007 char *name = match_strdup(&args[0]);
1008
1009 if (!name)
1010 return -ENOMEM;
1011 if (!strcmp(name, "none"))
1012 c->mount_opts.compr_type = UBIFS_COMPR_NONE;
1013 else if (!strcmp(name, "lzo"))
1014 c->mount_opts.compr_type = UBIFS_COMPR_LZO;
1015 else if (!strcmp(name, "zlib"))
1016 c->mount_opts.compr_type = UBIFS_COMPR_ZLIB;
1017 else {
1018 ubifs_err("unknown compressor \"%s\"", name);
1019 kfree(name);
1020 return -EINVAL;
1021 }
1022 kfree(name);
1023 c->mount_opts.override_compr = 1;
1024 c->default_compr = c->mount_opts.compr_type;
1025 break;
1026 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001027 default:
Artem Bityutskiy8379ea32009-05-29 12:34:52 +03001028 {
1029 unsigned long flag;
1030 struct super_block *sb = c->vfs_sb;
1031
1032 flag = parse_standard_option(p);
1033 if (!flag) {
1034 ubifs_err("unrecognized mount option \"%s\" "
1035 "or missing value", p);
1036 return -EINVAL;
1037 }
1038 sb->s_flags |= flag;
1039 break;
1040 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001041 }
1042 }
1043
1044 return 0;
1045}
1046
1047/**
1048 * destroy_journal - destroy journal data structures.
1049 * @c: UBIFS file-system description object
1050 *
1051 * This function destroys journal data structures including those that may have
1052 * been created by recovery functions.
1053 */
1054static void destroy_journal(struct ubifs_info *c)
1055{
1056 while (!list_empty(&c->unclean_leb_list)) {
1057 struct ubifs_unclean_leb *ucleb;
1058
1059 ucleb = list_entry(c->unclean_leb_list.next,
1060 struct ubifs_unclean_leb, list);
1061 list_del(&ucleb->list);
1062 kfree(ucleb);
1063 }
1064 while (!list_empty(&c->old_buds)) {
1065 struct ubifs_bud *bud;
1066
1067 bud = list_entry(c->old_buds.next, struct ubifs_bud, list);
1068 list_del(&bud->list);
1069 kfree(bud);
1070 }
1071 ubifs_destroy_idx_gc(c);
1072 ubifs_destroy_size_tree(c);
1073 ubifs_tnc_close(c);
1074 free_buds(c);
1075}
1076
1077/**
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001078 * bu_init - initialize bulk-read information.
1079 * @c: UBIFS file-system description object
1080 */
1081static void bu_init(struct ubifs_info *c)
1082{
1083 ubifs_assert(c->bulk_read == 1);
1084
1085 if (c->bu.buf)
1086 return; /* Already initialized */
1087
1088again:
1089 c->bu.buf = kmalloc(c->max_bu_buf_len, GFP_KERNEL | __GFP_NOWARN);
1090 if (!c->bu.buf) {
1091 if (c->max_bu_buf_len > UBIFS_KMALLOC_OK) {
1092 c->max_bu_buf_len = UBIFS_KMALLOC_OK;
1093 goto again;
1094 }
1095
1096 /* Just disable bulk-read */
1097 ubifs_warn("Cannot allocate %d bytes of memory for bulk-read, "
1098 "disabling it", c->max_bu_buf_len);
1099 c->mount_opts.bulk_read = 1;
1100 c->bulk_read = 0;
1101 return;
1102 }
1103}
1104
1105/**
Artem Bityutskiy57a450e2008-12-30 16:23:34 +02001106 * check_free_space - check if there is enough free space to mount.
1107 * @c: UBIFS file-system description object
1108 *
1109 * This function makes sure UBIFS has enough free space to be mounted in
1110 * read/write mode. UBIFS must always have some free space to allow deletions.
1111 */
1112static int check_free_space(struct ubifs_info *c)
1113{
1114 ubifs_assert(c->dark_wm > 0);
1115 if (c->lst.total_free + c->lst.total_dirty < c->dark_wm) {
1116 ubifs_err("insufficient free space to mount in read/write mode");
1117 dbg_dump_budg(c);
1118 dbg_dump_lprops(c);
Artem Bityutskiya2b9df32009-01-29 16:22:54 +02001119 return -ENOSPC;
Artem Bityutskiy57a450e2008-12-30 16:23:34 +02001120 }
1121 return 0;
1122}
1123
1124/**
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001125 * mount_ubifs - mount UBIFS file-system.
1126 * @c: UBIFS file-system description object
1127 *
1128 * This function mounts UBIFS file system. Returns zero in case of success and
1129 * a negative error code in case of failure.
1130 *
1131 * Note, the function does not de-allocate resources it it fails half way
1132 * through, and the caller has to do this instead.
1133 */
1134static int mount_ubifs(struct ubifs_info *c)
1135{
1136 struct super_block *sb = c->vfs_sb;
1137 int err, mounted_read_only = (sb->s_flags & MS_RDONLY);
1138 long long x;
1139 size_t sz;
1140
1141 err = init_constants_early(c);
1142 if (err)
1143 return err;
1144
Artem Bityutskiy17c2f9f2008-10-17 13:31:39 +03001145 err = ubifs_debugging_init(c);
1146 if (err)
1147 return err;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001148
1149 err = check_volume_empty(c);
1150 if (err)
1151 goto out_free;
1152
1153 if (c->empty && (mounted_read_only || c->ro_media)) {
1154 /*
1155 * This UBI volume is empty, and read-only, or the file system
1156 * is mounted read-only - we cannot format it.
1157 */
1158 ubifs_err("can't format empty UBI volume: read-only %s",
1159 c->ro_media ? "UBI volume" : "mount");
1160 err = -EROFS;
1161 goto out_free;
1162 }
1163
1164 if (c->ro_media && !mounted_read_only) {
1165 ubifs_err("cannot mount read-write - read-only media");
1166 err = -EROFS;
1167 goto out_free;
1168 }
1169
1170 /*
1171 * The requirement for the buffer is that it should fit indexing B-tree
1172 * height amount of integers. We assume the height if the TNC tree will
1173 * never exceed 64.
1174 */
1175 err = -ENOMEM;
1176 c->bottom_up_buf = kmalloc(BOTTOM_UP_HEIGHT * sizeof(int), GFP_KERNEL);
1177 if (!c->bottom_up_buf)
1178 goto out_free;
1179
1180 c->sbuf = vmalloc(c->leb_size);
1181 if (!c->sbuf)
1182 goto out_free;
1183
1184 if (!mounted_read_only) {
1185 c->ileb_buf = vmalloc(c->leb_size);
1186 if (!c->ileb_buf)
1187 goto out_free;
1188 }
1189
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001190 if (c->bulk_read == 1)
1191 bu_init(c);
1192
1193 /*
1194 * We have to check all CRCs, even for data nodes, when we mount the FS
1195 * (specifically, when we are replaying).
1196 */
Adrian Hunter2953e732008-09-04 16:26:00 +03001197 c->always_chk_crc = 1;
1198
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001199 err = ubifs_read_superblock(c);
1200 if (err)
1201 goto out_free;
1202
1203 /*
Artem Bityutskiy553dea42008-11-01 14:57:49 +02001204 * Make sure the compressor which is set as default in the superblock
Artem Bityutskiy57a450e2008-12-30 16:23:34 +02001205 * or overridden by mount options is actually compiled in.
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001206 */
1207 if (!ubifs_compr_present(c->default_compr)) {
Artem Bityutskiy553dea42008-11-01 14:57:49 +02001208 ubifs_err("'compressor \"%s\" is not compiled in",
1209 ubifs_compr_name(c->default_compr));
Corentin Chary8eec2f32009-05-25 08:49:10 +02001210 err = -ENOTSUPP;
Artem Bityutskiy553dea42008-11-01 14:57:49 +02001211 goto out_free;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001212 }
1213
Artem Bityutskiy79807d02008-12-27 19:18:00 +02001214 err = init_constants_sb(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001215 if (err)
Artem Bityutskiy17c2f9f2008-10-17 13:31:39 +03001216 goto out_free;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001217
1218 sz = ALIGN(c->max_idx_node_sz, c->min_io_size);
1219 sz = ALIGN(sz + c->max_idx_node_sz, c->min_io_size);
1220 c->cbuf = kmalloc(sz, GFP_NOFS);
1221 if (!c->cbuf) {
1222 err = -ENOMEM;
Artem Bityutskiy17c2f9f2008-10-17 13:31:39 +03001223 goto out_free;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001224 }
1225
Sebastian Siewior0855f312008-09-09 11:17:29 +02001226 sprintf(c->bgt_name, BGT_NAME_PATTERN, c->vi.ubi_num, c->vi.vol_id);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001227 if (!mounted_read_only) {
1228 err = alloc_wbufs(c);
1229 if (err)
1230 goto out_cbuf;
1231
1232 /* Create background thread */
Hunter Adrianfcabb342009-03-18 12:29:39 +01001233 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001234 if (IS_ERR(c->bgt)) {
1235 err = PTR_ERR(c->bgt);
1236 c->bgt = NULL;
1237 ubifs_err("cannot spawn \"%s\", error %d",
1238 c->bgt_name, err);
1239 goto out_wbufs;
1240 }
1241 wake_up_process(c->bgt);
1242 }
1243
1244 err = ubifs_read_master(c);
1245 if (err)
1246 goto out_master;
1247
Artem Bityutskiy79807d02008-12-27 19:18:00 +02001248 init_constants_master(c);
1249
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001250 if ((c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY)) != 0) {
1251 ubifs_msg("recovery needed");
1252 c->need_recovery = 1;
1253 if (!mounted_read_only) {
1254 err = ubifs_recover_inl_heads(c, c->sbuf);
1255 if (err)
1256 goto out_master;
1257 }
1258 } else if (!mounted_read_only) {
1259 /*
1260 * Set the "dirty" flag so that if we reboot uncleanly we
1261 * will notice this immediately on the next mount.
1262 */
1263 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1264 err = ubifs_write_master(c);
1265 if (err)
1266 goto out_master;
1267 }
1268
1269 err = ubifs_lpt_init(c, 1, !mounted_read_only);
1270 if (err)
1271 goto out_lpt;
1272
1273 err = dbg_check_idx_size(c, c->old_idx_sz);
1274 if (err)
1275 goto out_lpt;
1276
1277 err = ubifs_replay_journal(c);
1278 if (err)
1279 goto out_journal;
1280
Artem Bityutskiy1fb8bd02009-06-28 18:31:58 +03001281 /* Calculate 'min_idx_lebs' after journal replay */
1282 c->min_idx_lebs = ubifs_calc_min_idx_lebs(c);
1283
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001284 err = ubifs_mount_orphans(c, c->need_recovery, mounted_read_only);
1285 if (err)
1286 goto out_orphans;
1287
1288 if (!mounted_read_only) {
1289 int lnum;
1290
Artem Bityutskiy57a450e2008-12-30 16:23:34 +02001291 err = check_free_space(c);
1292 if (err)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001293 goto out_orphans;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001294
1295 /* Check for enough log space */
1296 lnum = c->lhead_lnum + 1;
1297 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1298 lnum = UBIFS_LOG_LNUM;
1299 if (lnum == c->ltail_lnum) {
1300 err = ubifs_consolidate_log(c);
1301 if (err)
1302 goto out_orphans;
1303 }
1304
1305 if (c->need_recovery) {
1306 err = ubifs_recover_size(c);
1307 if (err)
1308 goto out_orphans;
1309 err = ubifs_rcvry_gc_commit(c);
Artem Bityutskiyb4978e92009-01-23 18:23:03 +02001310 } else {
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001311 err = take_gc_lnum(c);
Artem Bityutskiyb4978e92009-01-23 18:23:03 +02001312 if (err)
1313 goto out_orphans;
1314
1315 /*
1316 * GC LEB may contain garbage if there was an unclean
1317 * reboot, and it should be un-mapped.
1318 */
1319 err = ubifs_leb_unmap(c, c->gc_lnum);
1320 if (err)
1321 return err;
1322 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001323
1324 err = dbg_check_lprops(c);
1325 if (err)
1326 goto out_orphans;
1327 } else if (c->need_recovery) {
1328 err = ubifs_recover_size(c);
1329 if (err)
1330 goto out_orphans;
Artem Bityutskiyb4978e92009-01-23 18:23:03 +02001331 } else {
1332 /*
1333 * Even if we mount read-only, we have to set space in GC LEB
1334 * to proper value because this affects UBIFS free space
1335 * reporting. We do not want to have a situation when
1336 * re-mounting from R/O to R/W changes amount of free space.
1337 */
1338 err = take_gc_lnum(c);
1339 if (err)
1340 goto out_orphans;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001341 }
1342
1343 spin_lock(&ubifs_infos_lock);
1344 list_add_tail(&c->infos_list, &ubifs_infos);
1345 spin_unlock(&ubifs_infos_lock);
1346
1347 if (c->need_recovery) {
1348 if (mounted_read_only)
1349 ubifs_msg("recovery deferred");
1350 else {
1351 c->need_recovery = 0;
1352 ubifs_msg("recovery completed");
Artem Bityutskiyb2213372009-03-15 17:20:22 +02001353 /*
1354 * GC LEB has to be empty and taken at this point. But
1355 * the journal head LEBs may also be accounted as
1356 * "empty taken" if they are empty.
1357 */
1358 ubifs_assert(c->lst.taken_empty_lebs > 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001359 }
Artem Bityutskiy6ba87c92009-01-26 16:12:20 +02001360 } else
Artem Bityutskiyb2213372009-03-15 17:20:22 +02001361 ubifs_assert(c->lst.taken_empty_lebs > 0);
Artem Bityutskiy552ff312008-10-23 11:49:28 +03001362
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001363 err = dbg_check_filesystem(c);
1364 if (err)
1365 goto out_infos;
1366
Artem Bityutskiy6ba87c92009-01-26 16:12:20 +02001367 err = dbg_debugfs_init_fs(c);
1368 if (err)
1369 goto out_infos;
1370
Adrian Hunter2953e732008-09-04 16:26:00 +03001371 c->always_chk_crc = 0;
1372
Artem Bityutskiyce769ca2008-07-18 12:54:21 +03001373 ubifs_msg("mounted UBI device %d, volume %d, name \"%s\"",
1374 c->vi.ubi_num, c->vi.vol_id, c->vi.name);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001375 if (mounted_read_only)
1376 ubifs_msg("mounted read-only");
1377 x = (long long)c->main_lebs * c->leb_size;
Artem Bityutskiy948cfb22008-08-20 11:56:33 +03001378 ubifs_msg("file system size: %lld bytes (%lld KiB, %lld MiB, %d "
1379 "LEBs)", x, x >> 10, x >> 20, c->main_lebs);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001380 x = (long long)c->log_lebs * c->leb_size + c->max_bud_bytes;
Artem Bityutskiy948cfb22008-08-20 11:56:33 +03001381 ubifs_msg("journal size: %lld bytes (%lld KiB, %lld MiB, %d "
1382 "LEBs)", x, x >> 10, x >> 20, c->log_lebs + c->max_bud_cnt);
Artem Bityutskiy963f0cf2009-03-26 12:51:21 +02001383 ubifs_msg("media format: w%d/r%d (latest is w%d/r%d)",
1384 c->fmt_version, c->ro_compat_version,
1385 UBIFS_FORMAT_VERSION, UBIFS_RO_COMPAT_VERSION);
Artem Bityutskiy948cfb22008-08-20 11:56:33 +03001386 ubifs_msg("default compressor: %s", ubifs_compr_name(c->default_compr));
Artem Bityutskiyfae7fb22008-10-17 18:49:23 +03001387 ubifs_msg("reserved for root: %llu bytes (%llu KiB)",
Artem Bityutskiy948cfb22008-08-20 11:56:33 +03001388 c->report_rp_size, c->report_rp_size >> 10);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001389
1390 dbg_msg("compiled on: " __DATE__ " at " __TIME__);
1391 dbg_msg("min. I/O unit size: %d bytes", c->min_io_size);
1392 dbg_msg("LEB size: %d bytes (%d KiB)",
Artem Bityutskiy948cfb22008-08-20 11:56:33 +03001393 c->leb_size, c->leb_size >> 10);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001394 dbg_msg("data journal heads: %d",
1395 c->jhead_cnt - NONDATA_JHEADS_CNT);
Joe Perches7f2f4e72009-12-14 18:01:13 -08001396 dbg_msg("UUID: %pUB", c->uuid);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001397 dbg_msg("big_lpt %d", c->big_lpt);
1398 dbg_msg("log LEBs: %d (%d - %d)",
1399 c->log_lebs, UBIFS_LOG_LNUM, c->log_last);
1400 dbg_msg("LPT area LEBs: %d (%d - %d)",
1401 c->lpt_lebs, c->lpt_first, c->lpt_last);
1402 dbg_msg("orphan area LEBs: %d (%d - %d)",
1403 c->orph_lebs, c->orph_first, c->orph_last);
1404 dbg_msg("main area LEBs: %d (%d - %d)",
1405 c->main_lebs, c->main_first, c->leb_cnt - 1);
1406 dbg_msg("index LEBs: %d", c->lst.idx_lebs);
1407 dbg_msg("total index bytes: %lld (%lld KiB, %lld MiB)",
1408 c->old_idx_sz, c->old_idx_sz >> 10, c->old_idx_sz >> 20);
1409 dbg_msg("key hash type: %d", c->key_hash_type);
1410 dbg_msg("tree fanout: %d", c->fanout);
1411 dbg_msg("reserved GC LEB: %d", c->gc_lnum);
1412 dbg_msg("first main LEB: %d", c->main_first);
Artem Bityutskiy8e5033a2008-12-30 18:37:45 +02001413 dbg_msg("max. znode size %d", c->max_znode_sz);
1414 dbg_msg("max. index node size %d", c->max_idx_node_sz);
1415 dbg_msg("node sizes: data %zu, inode %zu, dentry %zu",
1416 UBIFS_DATA_NODE_SZ, UBIFS_INO_NODE_SZ, UBIFS_DENT_NODE_SZ);
1417 dbg_msg("node sizes: trun %zu, sb %zu, master %zu",
1418 UBIFS_TRUN_NODE_SZ, UBIFS_SB_NODE_SZ, UBIFS_MST_NODE_SZ);
1419 dbg_msg("node sizes: ref %zu, cmt. start %zu, orph %zu",
1420 UBIFS_REF_NODE_SZ, UBIFS_CS_NODE_SZ, UBIFS_ORPH_NODE_SZ);
1421 dbg_msg("max. node sizes: data %zu, inode %zu dentry %zu",
1422 UBIFS_MAX_DATA_NODE_SZ, UBIFS_MAX_INO_NODE_SZ,
1423 UBIFS_MAX_DENT_NODE_SZ);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001424 dbg_msg("dead watermark: %d", c->dead_wm);
1425 dbg_msg("dark watermark: %d", c->dark_wm);
Artem Bityutskiy8e5033a2008-12-30 18:37:45 +02001426 dbg_msg("LEB overhead: %d", c->leb_overhead);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001427 x = (long long)c->main_lebs * c->dark_wm;
1428 dbg_msg("max. dark space: %lld (%lld KiB, %lld MiB)",
1429 x, x >> 10, x >> 20);
1430 dbg_msg("maximum bud bytes: %lld (%lld KiB, %lld MiB)",
1431 c->max_bud_bytes, c->max_bud_bytes >> 10,
1432 c->max_bud_bytes >> 20);
1433 dbg_msg("BG commit bud bytes: %lld (%lld KiB, %lld MiB)",
1434 c->bg_bud_bytes, c->bg_bud_bytes >> 10,
1435 c->bg_bud_bytes >> 20);
1436 dbg_msg("current bud bytes %lld (%lld KiB, %lld MiB)",
1437 c->bud_bytes, c->bud_bytes >> 10, c->bud_bytes >> 20);
1438 dbg_msg("max. seq. number: %llu", c->max_sqnum);
1439 dbg_msg("commit number: %llu", c->cmt_no);
1440
1441 return 0;
1442
1443out_infos:
1444 spin_lock(&ubifs_infos_lock);
1445 list_del(&c->infos_list);
1446 spin_unlock(&ubifs_infos_lock);
1447out_orphans:
1448 free_orphans(c);
1449out_journal:
1450 destroy_journal(c);
1451out_lpt:
1452 ubifs_lpt_free(c, 0);
1453out_master:
1454 kfree(c->mst_node);
1455 kfree(c->rcvrd_mst_node);
1456 if (c->bgt)
1457 kthread_stop(c->bgt);
1458out_wbufs:
1459 free_wbufs(c);
1460out_cbuf:
1461 kfree(c->cbuf);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001462out_free:
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001463 kfree(c->bu.buf);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001464 vfree(c->ileb_buf);
1465 vfree(c->sbuf);
1466 kfree(c->bottom_up_buf);
Artem Bityutskiy17c2f9f2008-10-17 13:31:39 +03001467 ubifs_debugging_exit(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001468 return err;
1469}
1470
1471/**
1472 * ubifs_umount - un-mount UBIFS file-system.
1473 * @c: UBIFS file-system description object
1474 *
1475 * Note, this function is called to free allocated resourced when un-mounting,
1476 * as well as free resources when an error occurred while we were half way
1477 * through mounting (error path cleanup function). So it has to make sure the
1478 * resource was actually allocated before freeing it.
1479 */
1480static void ubifs_umount(struct ubifs_info *c)
1481{
1482 dbg_gen("un-mounting UBI device %d, volume %d", c->vi.ubi_num,
1483 c->vi.vol_id);
1484
Artem Bityutskiy552ff312008-10-23 11:49:28 +03001485 dbg_debugfs_exit_fs(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001486 spin_lock(&ubifs_infos_lock);
1487 list_del(&c->infos_list);
1488 spin_unlock(&ubifs_infos_lock);
1489
1490 if (c->bgt)
1491 kthread_stop(c->bgt);
1492
1493 destroy_journal(c);
1494 free_wbufs(c);
1495 free_orphans(c);
1496 ubifs_lpt_free(c, 0);
1497
1498 kfree(c->cbuf);
1499 kfree(c->rcvrd_mst_node);
1500 kfree(c->mst_node);
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001501 kfree(c->bu.buf);
1502 vfree(c->ileb_buf);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001503 vfree(c->sbuf);
1504 kfree(c->bottom_up_buf);
Artem Bityutskiy17c2f9f2008-10-17 13:31:39 +03001505 ubifs_debugging_exit(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001506}
1507
1508/**
1509 * ubifs_remount_rw - re-mount in read-write mode.
1510 * @c: UBIFS file-system description object
1511 *
1512 * UBIFS avoids allocating many unnecessary resources when mounted in read-only
1513 * mode. This function allocates the needed resources and re-mounts UBIFS in
1514 * read-write mode.
1515 */
1516static int ubifs_remount_rw(struct ubifs_info *c)
1517{
1518 int err, lnum;
1519
Artem Bityutskiy963f0cf2009-03-26 12:51:21 +02001520 if (c->rw_incompat) {
1521 ubifs_err("the file-system is not R/W-compatible");
1522 ubifs_msg("on-flash format version is w%d/r%d, but software "
1523 "only supports up to version w%d/r%d", c->fmt_version,
1524 c->ro_compat_version, UBIFS_FORMAT_VERSION,
1525 UBIFS_RO_COMPAT_VERSION);
1526 return -EROFS;
1527 }
1528
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001529 mutex_lock(&c->umount_mutex);
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001530 dbg_save_space_info(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001531 c->remounting_rw = 1;
Adrian Hunter2953e732008-09-04 16:26:00 +03001532 c->always_chk_crc = 1;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001533
Artem Bityutskiy57a450e2008-12-30 16:23:34 +02001534 err = check_free_space(c);
1535 if (err)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001536 goto out;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001537
1538 if (c->old_leb_cnt != c->leb_cnt) {
1539 struct ubifs_sb_node *sup;
1540
1541 sup = ubifs_read_sb_node(c);
1542 if (IS_ERR(sup)) {
1543 err = PTR_ERR(sup);
1544 goto out;
1545 }
1546 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
1547 err = ubifs_write_sb_node(c, sup);
1548 if (err)
1549 goto out;
1550 }
1551
1552 if (c->need_recovery) {
1553 ubifs_msg("completing deferred recovery");
1554 err = ubifs_write_rcvrd_mst_node(c);
1555 if (err)
1556 goto out;
1557 err = ubifs_recover_size(c);
1558 if (err)
1559 goto out;
1560 err = ubifs_clean_lebs(c, c->sbuf);
1561 if (err)
1562 goto out;
1563 err = ubifs_recover_inl_heads(c, c->sbuf);
1564 if (err)
1565 goto out;
Adrian Hunter49d128a2009-01-26 10:55:40 +02001566 } else {
1567 /* A readonly mount is not allowed to have orphans */
1568 ubifs_assert(c->tot_orphans == 0);
1569 err = ubifs_clear_orphans(c);
1570 if (err)
1571 goto out;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001572 }
1573
1574 if (!(c->mst_node->flags & cpu_to_le32(UBIFS_MST_DIRTY))) {
1575 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_DIRTY);
1576 err = ubifs_write_master(c);
1577 if (err)
1578 goto out;
1579 }
1580
1581 c->ileb_buf = vmalloc(c->leb_size);
1582 if (!c->ileb_buf) {
1583 err = -ENOMEM;
1584 goto out;
1585 }
1586
1587 err = ubifs_lpt_init(c, 0, 1);
1588 if (err)
1589 goto out;
1590
1591 err = alloc_wbufs(c);
1592 if (err)
1593 goto out;
1594
1595 ubifs_create_buds_lists(c);
1596
1597 /* Create background thread */
Hunter Adrianfcabb342009-03-18 12:29:39 +01001598 c->bgt = kthread_create(ubifs_bg_thread, c, "%s", c->bgt_name);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001599 if (IS_ERR(c->bgt)) {
1600 err = PTR_ERR(c->bgt);
1601 c->bgt = NULL;
1602 ubifs_err("cannot spawn \"%s\", error %d",
1603 c->bgt_name, err);
Adrian Hunter2953e732008-09-04 16:26:00 +03001604 goto out;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001605 }
1606 wake_up_process(c->bgt);
1607
1608 c->orph_buf = vmalloc(c->leb_size);
Adrian Hunter2953e732008-09-04 16:26:00 +03001609 if (!c->orph_buf) {
1610 err = -ENOMEM;
1611 goto out;
1612 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001613
1614 /* Check for enough log space */
1615 lnum = c->lhead_lnum + 1;
1616 if (lnum >= UBIFS_LOG_LNUM + c->log_lebs)
1617 lnum = UBIFS_LOG_LNUM;
1618 if (lnum == c->ltail_lnum) {
1619 err = ubifs_consolidate_log(c);
1620 if (err)
1621 goto out;
1622 }
1623
1624 if (c->need_recovery)
1625 err = ubifs_rcvry_gc_commit(c);
1626 else
Artem Bityutskiyb4978e92009-01-23 18:23:03 +02001627 err = ubifs_leb_unmap(c, c->gc_lnum);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001628 if (err)
1629 goto out;
1630
1631 if (c->need_recovery) {
1632 c->need_recovery = 0;
1633 ubifs_msg("deferred recovery completed");
1634 }
1635
1636 dbg_gen("re-mounted read-write");
1637 c->vfs_sb->s_flags &= ~MS_RDONLY;
1638 c->remounting_rw = 0;
Adrian Hunter2953e732008-09-04 16:26:00 +03001639 c->always_chk_crc = 0;
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001640 err = dbg_check_space_info(c);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001641 mutex_unlock(&c->umount_mutex);
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001642 return err;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001643
1644out:
1645 vfree(c->orph_buf);
1646 c->orph_buf = NULL;
1647 if (c->bgt) {
1648 kthread_stop(c->bgt);
1649 c->bgt = NULL;
1650 }
1651 free_wbufs(c);
1652 vfree(c->ileb_buf);
1653 c->ileb_buf = NULL;
1654 ubifs_lpt_free(c, 1);
1655 c->remounting_rw = 0;
Adrian Hunter2953e732008-09-04 16:26:00 +03001656 c->always_chk_crc = 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001657 mutex_unlock(&c->umount_mutex);
1658 return err;
1659}
1660
1661/**
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001662 * ubifs_remount_ro - re-mount in read-only mode.
1663 * @c: UBIFS file-system description object
1664 *
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001665 * We assume VFS has stopped writing. Possibly the background thread could be
1666 * running a commit, however kthread_stop will wait in that case.
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001667 */
1668static void ubifs_remount_ro(struct ubifs_info *c)
1669{
1670 int i, err;
1671
1672 ubifs_assert(!c->need_recovery);
Artem Bityutskiy6ba87c92009-01-26 16:12:20 +02001673 ubifs_assert(!(c->vfs_sb->s_flags & MS_RDONLY));
Artem Bityutskiye4d9b6c2009-01-23 14:17:36 +02001674
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001675 mutex_lock(&c->umount_mutex);
1676 if (c->bgt) {
1677 kthread_stop(c->bgt);
1678 c->bgt = NULL;
1679 }
1680
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001681 dbg_save_space_info(c);
1682
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001683 for (i = 0; i < c->jhead_cnt; i++) {
1684 ubifs_wbuf_sync(&c->jheads[i].wbuf);
Artem Bityutskiyf2c5dbd2009-05-28 16:24:15 +03001685 hrtimer_cancel(&c->jheads[i].wbuf.timer);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001686 }
1687
Artem Bityutskiye4d9b6c2009-01-23 14:17:36 +02001688 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
1689 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
1690 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
1691 err = ubifs_write_master(c);
1692 if (err)
1693 ubifs_ro_mode(c, err);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001694
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001695 free_wbufs(c);
1696 vfree(c->orph_buf);
1697 c->orph_buf = NULL;
1698 vfree(c->ileb_buf);
1699 c->ileb_buf = NULL;
1700 ubifs_lpt_free(c, 1);
Artem Bityutskiy84abf972009-01-23 14:54:59 +02001701 err = dbg_check_space_info(c);
1702 if (err)
1703 ubifs_ro_mode(c, err);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001704 mutex_unlock(&c->umount_mutex);
1705}
1706
1707static void ubifs_put_super(struct super_block *sb)
1708{
1709 int i;
1710 struct ubifs_info *c = sb->s_fs_info;
1711
1712 ubifs_msg("un-mount UBI device %d, volume %d", c->vi.ubi_num,
1713 c->vi.vol_id);
Christoph Hellwig6cfd0142009-05-05 15:40:36 +02001714
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001715 /*
1716 * The following asserts are only valid if there has not been a failure
1717 * of the media. For example, there will be dirty inodes if we failed
1718 * to write them back because of I/O errors.
1719 */
1720 ubifs_assert(atomic_long_read(&c->dirty_pg_cnt) == 0);
1721 ubifs_assert(c->budg_idx_growth == 0);
Artem Bityutskiy7d32c2b2008-07-18 18:54:29 +03001722 ubifs_assert(c->budg_dd_growth == 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001723 ubifs_assert(c->budg_data_growth == 0);
1724
1725 /*
1726 * The 'c->umount_lock' prevents races between UBIFS memory shrinker
1727 * and file system un-mount. Namely, it prevents the shrinker from
1728 * picking this superblock for shrinking - it will be just skipped if
1729 * the mutex is locked.
1730 */
1731 mutex_lock(&c->umount_mutex);
1732 if (!(c->vfs_sb->s_flags & MS_RDONLY)) {
1733 /*
1734 * First of all kill the background thread to make sure it does
1735 * not interfere with un-mounting and freeing resources.
1736 */
1737 if (c->bgt) {
1738 kthread_stop(c->bgt);
1739 c->bgt = NULL;
1740 }
1741
1742 /* Synchronize write-buffers */
1743 if (c->jheads)
Artem Bityutskiy0b335b92009-06-23 12:30:43 +03001744 for (i = 0; i < c->jhead_cnt; i++)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001745 ubifs_wbuf_sync(&c->jheads[i].wbuf);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001746
1747 /*
1748 * On fatal errors c->ro_media is set to 1, in which case we do
1749 * not write the master node.
1750 */
1751 if (!c->ro_media) {
1752 /*
1753 * We are being cleanly unmounted which means the
1754 * orphans were killed - indicate this in the master
1755 * node. Also save the reserved GC LEB number.
1756 */
1757 int err;
1758
1759 c->mst_node->flags &= ~cpu_to_le32(UBIFS_MST_DIRTY);
1760 c->mst_node->flags |= cpu_to_le32(UBIFS_MST_NO_ORPHS);
1761 c->mst_node->gc_lnum = cpu_to_le32(c->gc_lnum);
1762 err = ubifs_write_master(c);
1763 if (err)
1764 /*
1765 * Recovery will attempt to fix the master area
1766 * next mount, so we just print a message and
1767 * continue to unmount normally.
1768 */
1769 ubifs_err("failed to write master node, "
1770 "error %d", err);
1771 }
1772 }
1773
1774 ubifs_umount(c);
1775 bdi_destroy(&c->bdi);
1776 ubi_close_volume(c->ubi);
1777 mutex_unlock(&c->umount_mutex);
1778 kfree(c);
1779}
1780
1781static int ubifs_remount_fs(struct super_block *sb, int *flags, char *data)
1782{
1783 int err;
1784 struct ubifs_info *c = sb->s_fs_info;
1785
1786 dbg_gen("old flags %#lx, new flags %#x", sb->s_flags, *flags);
1787
1788 err = ubifs_parse_options(c, data, 1);
1789 if (err) {
1790 ubifs_err("invalid or unknown remount parameter");
1791 return err;
1792 }
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001793
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001794 if ((sb->s_flags & MS_RDONLY) && !(*flags & MS_RDONLY)) {
Artem Bityutskiye4d9b6c2009-01-23 14:17:36 +02001795 if (c->ro_media) {
Adrian Hunterb466f172009-01-29 12:59:33 +02001796 ubifs_msg("cannot re-mount due to prior errors");
Artem Bityutskiya2b9df32009-01-29 16:22:54 +02001797 return -EROFS;
Artem Bityutskiye4d9b6c2009-01-23 14:17:36 +02001798 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001799 err = ubifs_remount_rw(c);
Artem Bityutskiye9d6bbc2009-07-19 13:51:04 +03001800 if (err)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001801 return err;
Adrian Hunterb466f172009-01-29 12:59:33 +02001802 } else if (!(sb->s_flags & MS_RDONLY) && (*flags & MS_RDONLY)) {
1803 if (c->ro_media) {
1804 ubifs_msg("cannot re-mount due to prior errors");
Artem Bityutskiya2b9df32009-01-29 16:22:54 +02001805 return -EROFS;
Adrian Hunterb466f172009-01-29 12:59:33 +02001806 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001807 ubifs_remount_ro(c);
Adrian Hunterb466f172009-01-29 12:59:33 +02001808 }
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001809
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001810 if (c->bulk_read == 1)
1811 bu_init(c);
1812 else {
1813 dbg_gen("disable bulk-read");
1814 kfree(c->bu.buf);
1815 c->bu.buf = NULL;
1816 }
1817
Artem Bityutskiyb2213372009-03-15 17:20:22 +02001818 ubifs_assert(c->lst.taken_empty_lebs > 0);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001819 return 0;
1820}
1821
Artem Bityutskiye8b81562009-01-15 17:43:23 +02001822const struct super_operations ubifs_super_operations = {
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001823 .alloc_inode = ubifs_alloc_inode,
1824 .destroy_inode = ubifs_destroy_inode,
1825 .put_super = ubifs_put_super,
1826 .write_inode = ubifs_write_inode,
1827 .delete_inode = ubifs_delete_inode,
1828 .statfs = ubifs_statfs,
1829 .dirty_inode = ubifs_dirty_inode,
1830 .remount_fs = ubifs_remount_fs,
1831 .show_options = ubifs_show_options,
1832 .sync_fs = ubifs_sync_fs,
1833};
1834
1835/**
1836 * open_ubi - parse UBI device name string and open the UBI device.
1837 * @name: UBI volume name
1838 * @mode: UBI volume open mode
1839 *
Corentin Chary97223242009-09-28 21:10:12 +02001840 * The primary method of mounting UBIFS is by specifying the UBI volume
1841 * character device node path. However, UBIFS may also be mounted withoug any
1842 * character device node using one of the following methods:
1843 *
1844 * o ubiX_Y - mount UBI device number X, volume Y;
1845 * o ubiY - mount UBI device number 0, volume Y;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001846 * o ubiX:NAME - mount UBI device X, volume with name NAME;
1847 * o ubi:NAME - mount UBI device 0, volume with name NAME.
1848 *
1849 * Alternative '!' separator may be used instead of ':' (because some shells
1850 * like busybox may interpret ':' as an NFS host name separator). This function
Corentin Chary97223242009-09-28 21:10:12 +02001851 * returns UBI volume description object in case of success and a negative
1852 * error code in case of failure.
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001853 */
1854static struct ubi_volume_desc *open_ubi(const char *name, int mode)
1855{
Corentin Chary97223242009-09-28 21:10:12 +02001856 struct ubi_volume_desc *ubi;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001857 int dev, vol;
1858 char *endptr;
1859
Corentin Chary97223242009-09-28 21:10:12 +02001860 /* First, try to open using the device node path method */
1861 ubi = ubi_open_volume_path(name, mode);
1862 if (!IS_ERR(ubi))
1863 return ubi;
1864
1865 /* Try the "nodev" method */
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001866 if (name[0] != 'u' || name[1] != 'b' || name[2] != 'i')
1867 return ERR_PTR(-EINVAL);
1868
1869 /* ubi:NAME method */
1870 if ((name[3] == ':' || name[3] == '!') && name[4] != '\0')
1871 return ubi_open_volume_nm(0, name + 4, mode);
1872
1873 if (!isdigit(name[3]))
1874 return ERR_PTR(-EINVAL);
1875
1876 dev = simple_strtoul(name + 3, &endptr, 0);
1877
1878 /* ubiY method */
1879 if (*endptr == '\0')
1880 return ubi_open_volume(0, dev, mode);
1881
1882 /* ubiX_Y method */
1883 if (*endptr == '_' && isdigit(endptr[1])) {
1884 vol = simple_strtoul(endptr + 1, &endptr, 0);
1885 if (*endptr != '\0')
1886 return ERR_PTR(-EINVAL);
1887 return ubi_open_volume(dev, vol, mode);
1888 }
1889
1890 /* ubiX:NAME method */
1891 if ((*endptr == ':' || *endptr == '!') && endptr[1] != '\0')
1892 return ubi_open_volume_nm(dev, ++endptr, mode);
1893
1894 return ERR_PTR(-EINVAL);
1895}
1896
1897static int ubifs_fill_super(struct super_block *sb, void *data, int silent)
1898{
1899 struct ubi_volume_desc *ubi = sb->s_fs_info;
1900 struct ubifs_info *c;
1901 struct inode *root;
1902 int err;
1903
1904 c = kzalloc(sizeof(struct ubifs_info), GFP_KERNEL);
1905 if (!c)
1906 return -ENOMEM;
1907
1908 spin_lock_init(&c->cnt_lock);
1909 spin_lock_init(&c->cs_lock);
1910 spin_lock_init(&c->buds_lock);
1911 spin_lock_init(&c->space_lock);
1912 spin_lock_init(&c->orphan_lock);
1913 init_rwsem(&c->commit_sem);
1914 mutex_init(&c->lp_mutex);
1915 mutex_init(&c->tnc_mutex);
1916 mutex_init(&c->log_mutex);
1917 mutex_init(&c->mst_mutex);
1918 mutex_init(&c->umount_mutex);
Artem Bityutskiy3477d202008-11-19 11:53:15 +02001919 mutex_init(&c->bu_mutex);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001920 init_waitqueue_head(&c->cmt_wq);
1921 c->buds = RB_ROOT;
1922 c->old_idx = RB_ROOT;
1923 c->size_tree = RB_ROOT;
1924 c->orph_tree = RB_ROOT;
1925 INIT_LIST_HEAD(&c->infos_list);
1926 INIT_LIST_HEAD(&c->idx_gc);
1927 INIT_LIST_HEAD(&c->replay_list);
1928 INIT_LIST_HEAD(&c->replay_buds);
1929 INIT_LIST_HEAD(&c->uncat_list);
1930 INIT_LIST_HEAD(&c->empty_list);
1931 INIT_LIST_HEAD(&c->freeable_list);
1932 INIT_LIST_HEAD(&c->frdi_idx_list);
1933 INIT_LIST_HEAD(&c->unclean_leb_list);
1934 INIT_LIST_HEAD(&c->old_buds);
1935 INIT_LIST_HEAD(&c->orph_list);
1936 INIT_LIST_HEAD(&c->orph_new);
1937
Artem Bityutskiy8379ea32009-05-29 12:34:52 +03001938 c->vfs_sb = sb;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001939 c->highest_inum = UBIFS_FIRST_INO;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001940 c->lhead_lnum = c->ltail_lnum = UBIFS_LOG_LNUM;
1941
1942 ubi_get_volume_info(ubi, &c->vi);
1943 ubi_get_device_info(c->vi.ubi_num, &c->di);
1944
1945 /* Re-open the UBI device in read-write mode */
1946 c->ubi = ubi_open_volume(c->vi.ubi_num, c->vi.vol_id, UBI_READWRITE);
1947 if (IS_ERR(c->ubi)) {
1948 err = PTR_ERR(c->ubi);
1949 goto out_free;
1950 }
1951
1952 /*
Artem Bityutskiy0a883a02008-08-13 14:13:26 +03001953 * UBIFS provides 'backing_dev_info' in order to disable read-ahead. For
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001954 * UBIFS, I/O is not deferred, it is done immediately in readpage,
1955 * which means the user would have to wait not just for their own I/O
Artem Bityutskiy0a883a02008-08-13 14:13:26 +03001956 * but the read-ahead I/O as well i.e. completely pointless.
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001957 *
1958 * Read-ahead will be disabled because @c->bdi.ra_pages is 0.
1959 */
Jens Axboed9938312009-06-12 14:45:52 +02001960 c->bdi.name = "ubifs",
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001961 c->bdi.capabilities = BDI_CAP_MAP_COPY;
1962 c->bdi.unplug_io_fn = default_unplug_io_fn;
1963 err = bdi_init(&c->bdi);
1964 if (err)
1965 goto out_close;
Daniel Mack7fcd9c32009-07-02 17:15:47 +02001966 err = bdi_register(&c->bdi, NULL, "ubifs_%d_%d",
1967 c->vi.ubi_num, c->vi.vol_id);
Jens Axboea979eff2009-05-29 09:19:23 +02001968 if (err)
1969 goto out_bdi;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001970
1971 err = ubifs_parse_options(c, data, 0);
1972 if (err)
1973 goto out_bdi;
1974
Jens Axboe32a88aa2009-09-16 15:02:33 +02001975 sb->s_bdi = &c->bdi;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001976 sb->s_fs_info = c;
1977 sb->s_magic = UBIFS_SUPER_MAGIC;
1978 sb->s_blocksize = UBIFS_BLOCK_SIZE;
1979 sb->s_blocksize_bits = UBIFS_BLOCK_SHIFT;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03001980 sb->s_maxbytes = c->max_inode_sz = key_max_inode_size(c);
1981 if (c->max_inode_sz > MAX_LFS_FILESIZE)
1982 sb->s_maxbytes = c->max_inode_sz = MAX_LFS_FILESIZE;
1983 sb->s_op = &ubifs_super_operations;
1984
1985 mutex_lock(&c->umount_mutex);
1986 err = mount_ubifs(c);
1987 if (err) {
1988 ubifs_assert(err < 0);
1989 goto out_unlock;
1990 }
1991
1992 /* Read the root inode */
1993 root = ubifs_iget(sb, UBIFS_ROOT_INO);
1994 if (IS_ERR(root)) {
1995 err = PTR_ERR(root);
1996 goto out_umount;
1997 }
1998
1999 sb->s_root = d_alloc_root(root);
2000 if (!sb->s_root)
2001 goto out_iput;
2002
2003 mutex_unlock(&c->umount_mutex);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002004 return 0;
2005
2006out_iput:
2007 iput(root);
2008out_umount:
2009 ubifs_umount(c);
2010out_unlock:
2011 mutex_unlock(&c->umount_mutex);
2012out_bdi:
2013 bdi_destroy(&c->bdi);
2014out_close:
2015 ubi_close_volume(c->ubi);
2016out_free:
2017 kfree(c);
2018 return err;
2019}
2020
2021static int sb_test(struct super_block *sb, void *data)
2022{
2023 dev_t *dev = data;
Artem Bityutskiy7c83f5c2009-05-25 19:23:04 +03002024 struct ubifs_info *c = sb->s_fs_info;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002025
Artem Bityutskiy7c83f5c2009-05-25 19:23:04 +03002026 return c->vi.cdev == *dev;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002027}
2028
2029static int ubifs_get_sb(struct file_system_type *fs_type, int flags,
2030 const char *name, void *data, struct vfsmount *mnt)
2031{
2032 struct ubi_volume_desc *ubi;
2033 struct ubi_volume_info vi;
2034 struct super_block *sb;
2035 int err;
2036
2037 dbg_gen("name %s, flags %#x", name, flags);
2038
2039 /*
2040 * Get UBI device number and volume ID. Mount it read-only so far
2041 * because this might be a new mount point, and UBI allows only one
2042 * read-write user at a time.
2043 */
2044 ubi = open_ubi(name, UBI_READONLY);
2045 if (IS_ERR(ubi)) {
2046 ubifs_err("cannot open \"%s\", error %d",
2047 name, (int)PTR_ERR(ubi));
2048 return PTR_ERR(ubi);
2049 }
2050 ubi_get_volume_info(ubi, &vi);
2051
2052 dbg_gen("opened ubi%d_%d", vi.ubi_num, vi.vol_id);
2053
Artem Bityutskiy7c83f5c2009-05-25 19:23:04 +03002054 sb = sget(fs_type, &sb_test, &set_anon_super, &vi.cdev);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002055 if (IS_ERR(sb)) {
2056 err = PTR_ERR(sb);
2057 goto out_close;
2058 }
2059
2060 if (sb->s_root) {
2061 /* A new mount point for already mounted UBIFS */
2062 dbg_gen("this ubi volume is already mounted");
2063 if ((flags ^ sb->s_flags) & MS_RDONLY) {
2064 err = -EBUSY;
2065 goto out_deact;
2066 }
2067 } else {
2068 sb->s_flags = flags;
2069 /*
2070 * Pass 'ubi' to 'fill_super()' in sb->s_fs_info where it is
2071 * replaced by 'c'.
2072 */
2073 sb->s_fs_info = ubi;
2074 err = ubifs_fill_super(sb, data, flags & MS_SILENT ? 1 : 0);
2075 if (err)
2076 goto out_deact;
2077 /* We do not support atime */
2078 sb->s_flags |= MS_ACTIVE | MS_NOATIME;
2079 }
2080
2081 /* 'fill_super()' opens ubi again so we must close it here */
2082 ubi_close_volume(ubi);
2083
Sukadev Bhattiprolua3ec9472009-03-04 12:06:34 -08002084 simple_set_mnt(mnt, sb);
2085 return 0;
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002086
2087out_deact:
Al Viro6f5bbff2009-05-06 01:34:22 -04002088 deactivate_locked_super(sb);
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002089out_close:
2090 ubi_close_volume(ubi);
2091 return err;
2092}
2093
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002094static struct file_system_type ubifs_fs_type = {
2095 .name = "ubifs",
2096 .owner = THIS_MODULE,
2097 .get_sb = ubifs_get_sb,
Artem Bityutskiy7c83f5c2009-05-25 19:23:04 +03002098 .kill_sb = kill_anon_super,
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002099};
2100
2101/*
2102 * Inode slab cache constructor.
2103 */
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07002104static void inode_slab_ctor(void *obj)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002105{
2106 struct ubifs_inode *ui = obj;
2107 inode_init_once(&ui->vfs_inode);
2108}
2109
2110static int __init ubifs_init(void)
2111{
2112 int err;
2113
2114 BUILD_BUG_ON(sizeof(struct ubifs_ch) != 24);
2115
2116 /* Make sure node sizes are 8-byte aligned */
2117 BUILD_BUG_ON(UBIFS_CH_SZ & 7);
2118 BUILD_BUG_ON(UBIFS_INO_NODE_SZ & 7);
2119 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ & 7);
2120 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ & 7);
2121 BUILD_BUG_ON(UBIFS_DATA_NODE_SZ & 7);
2122 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ & 7);
2123 BUILD_BUG_ON(UBIFS_SB_NODE_SZ & 7);
2124 BUILD_BUG_ON(UBIFS_MST_NODE_SZ & 7);
2125 BUILD_BUG_ON(UBIFS_REF_NODE_SZ & 7);
2126 BUILD_BUG_ON(UBIFS_CS_NODE_SZ & 7);
2127 BUILD_BUG_ON(UBIFS_ORPH_NODE_SZ & 7);
2128
2129 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ & 7);
2130 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ & 7);
2131 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ & 7);
2132 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ & 7);
2133 BUILD_BUG_ON(UBIFS_MAX_NODE_SZ & 7);
2134 BUILD_BUG_ON(MIN_WRITE_SZ & 7);
2135
2136 /* Check min. node size */
2137 BUILD_BUG_ON(UBIFS_INO_NODE_SZ < MIN_WRITE_SZ);
2138 BUILD_BUG_ON(UBIFS_DENT_NODE_SZ < MIN_WRITE_SZ);
2139 BUILD_BUG_ON(UBIFS_XENT_NODE_SZ < MIN_WRITE_SZ);
2140 BUILD_BUG_ON(UBIFS_TRUN_NODE_SZ < MIN_WRITE_SZ);
2141
2142 BUILD_BUG_ON(UBIFS_MAX_DENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
2143 BUILD_BUG_ON(UBIFS_MAX_XENT_NODE_SZ > UBIFS_MAX_NODE_SZ);
2144 BUILD_BUG_ON(UBIFS_MAX_DATA_NODE_SZ > UBIFS_MAX_NODE_SZ);
2145 BUILD_BUG_ON(UBIFS_MAX_INO_NODE_SZ > UBIFS_MAX_NODE_SZ);
2146
2147 /* Defined node sizes */
2148 BUILD_BUG_ON(UBIFS_SB_NODE_SZ != 4096);
2149 BUILD_BUG_ON(UBIFS_MST_NODE_SZ != 512);
2150 BUILD_BUG_ON(UBIFS_INO_NODE_SZ != 160);
2151 BUILD_BUG_ON(UBIFS_REF_NODE_SZ != 64);
2152
2153 /*
Artem Bityutskiya1dc0802008-11-01 14:20:50 +02002154 * We use 2 bit wide bit-fields to store compression type, which should
2155 * be amended if more compressors are added. The bit-fields are:
Artem Bityutskiy553dea42008-11-01 14:57:49 +02002156 * @compr_type in 'struct ubifs_inode', @default_compr in
2157 * 'struct ubifs_info' and @compr_type in 'struct ubifs_mount_opts'.
Artem Bityutskiya1dc0802008-11-01 14:20:50 +02002158 */
2159 BUILD_BUG_ON(UBIFS_COMPR_TYPES_CNT > 4);
2160
2161 /*
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002162 * We require that PAGE_CACHE_SIZE is greater-than-or-equal-to
2163 * UBIFS_BLOCK_SIZE. It is assumed that both are powers of 2.
2164 */
2165 if (PAGE_CACHE_SIZE < UBIFS_BLOCK_SIZE) {
2166 ubifs_err("VFS page cache size is %u bytes, but UBIFS requires"
2167 " at least 4096 bytes",
2168 (unsigned int)PAGE_CACHE_SIZE);
2169 return -EINVAL;
2170 }
2171
2172 err = register_filesystem(&ubifs_fs_type);
2173 if (err) {
2174 ubifs_err("cannot register file system, error %d", err);
2175 return err;
2176 }
2177
2178 err = -ENOMEM;
2179 ubifs_inode_slab = kmem_cache_create("ubifs_inode_slab",
2180 sizeof(struct ubifs_inode), 0,
2181 SLAB_MEM_SPREAD | SLAB_RECLAIM_ACCOUNT,
2182 &inode_slab_ctor);
2183 if (!ubifs_inode_slab)
2184 goto out_reg;
2185
2186 register_shrinker(&ubifs_shrinker_info);
2187
2188 err = ubifs_compressors_init();
2189 if (err)
Artem Bityutskiy552ff312008-10-23 11:49:28 +03002190 goto out_shrinker;
2191
2192 err = dbg_debugfs_init();
2193 if (err)
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002194 goto out_compr;
2195
2196 return 0;
2197
2198out_compr:
Artem Bityutskiy552ff312008-10-23 11:49:28 +03002199 ubifs_compressors_exit();
2200out_shrinker:
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002201 unregister_shrinker(&ubifs_shrinker_info);
2202 kmem_cache_destroy(ubifs_inode_slab);
2203out_reg:
2204 unregister_filesystem(&ubifs_fs_type);
2205 return err;
2206}
2207/* late_initcall to let compressors initialize first */
2208late_initcall(ubifs_init);
2209
2210static void __exit ubifs_exit(void)
2211{
2212 ubifs_assert(list_empty(&ubifs_infos));
2213 ubifs_assert(atomic_long_read(&ubifs_clean_zn_cnt) == 0);
2214
Artem Bityutskiy552ff312008-10-23 11:49:28 +03002215 dbg_debugfs_exit();
Artem Bityutskiy1e517642008-07-14 19:08:37 +03002216 ubifs_compressors_exit();
2217 unregister_shrinker(&ubifs_shrinker_info);
2218 kmem_cache_destroy(ubifs_inode_slab);
2219 unregister_filesystem(&ubifs_fs_type);
2220}
2221module_exit(ubifs_exit);
2222
2223MODULE_LICENSE("GPL");
2224MODULE_VERSION(__stringify(UBIFS_VERSION));
2225MODULE_AUTHOR("Artem Bityutskiy, Adrian Hunter");
2226MODULE_DESCRIPTION("UBIFS - UBI File System");