2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation.
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.
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
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
19 * Authors: Artem Bityutskiy (Битюцкий Артём)
24 * This file implements UBIFS superblock. The superblock is stored at the first
25 * LEB of the volume and is never changed by UBIFS. Only user-space tools may
26 * change it. The superblock node mostly contains geometry information.
30 #include <linux/slab.h>
31 #include <linux/random.h>
32 #include <linux/math64.h>
35 * Default journal size in logical eraseblocks as a percent of total
38 #define DEFAULT_JNL_PERCENT 5
40 /* Default maximum journal size in bytes */
41 #define DEFAULT_MAX_JNL (32*1024*1024)
43 /* Default indexing tree fanout */
44 #define DEFAULT_FANOUT 8
46 /* Default number of data journal heads */
47 #define DEFAULT_JHEADS_CNT 1
49 /* Default positions of different LEBs in the main area */
50 #define DEFAULT_IDX_LEB 0
51 #define DEFAULT_DATA_LEB 1
52 #define DEFAULT_GC_LEB 2
54 /* Default number of LEB numbers in LPT's save table */
55 #define DEFAULT_LSAVE_CNT 256
57 /* Default reserved pool size as a percent of maximum free space */
58 #define DEFAULT_RP_PERCENT 5
60 /* The default maximum size of reserved pool in bytes */
61 #define DEFAULT_MAX_RP_SIZE (16*1024*1024)
63 #define UBIFS_ONE_GIGA 1024*1024*1024
65 /* Default time granularity in nanoseconds */
66 #define DEFAULT_TIME_GRAN 1000000000
69 * create_default_filesystem - format empty UBI volume.
70 * @c: UBIFS file-system description object
72 * This function creates default empty file-system. Returns zero in case of
73 * success and a negative error code in case of failure.
75 static int create_default_filesystem(struct ubifs_info
*c
)
77 struct ubifs_sb_node
*sup
;
78 struct ubifs_mst_node
*mst
;
79 struct ubifs_idx_node
*idx
;
80 struct ubifs_branch
*br
;
81 struct ubifs_ino_node
*ino
;
82 struct ubifs_cs_node
*cs
;
84 int err
, tmp
, jnl_lebs
, log_lebs
, max_buds
, main_lebs
, main_first
;
85 int lpt_lebs
, lpt_first
, orph_lebs
, big_lpt
, ino_waste
, sup_flags
= 0;
86 int min_leb_cnt
= UBIFS_MIN_LEB_CNT
;
87 long long tmp64
, main_bytes
;
90 /* Some functions called from here depend on the @c->key_len filed */
91 c
->key_len
= UBIFS_SK_LEN
;
94 * First of all, we have to calculate default file-system geometry -
95 * log size, journal size, etc.
97 if (c
->leb_cnt
< 0x7FFFFFFF / DEFAULT_JNL_PERCENT
)
98 /* We can first multiply then divide and have no overflow */
99 jnl_lebs
= c
->leb_cnt
* DEFAULT_JNL_PERCENT
/ 100;
101 jnl_lebs
= (c
->leb_cnt
/ 100) * DEFAULT_JNL_PERCENT
;
103 if (jnl_lebs
< UBIFS_MIN_JNL_LEBS
)
104 jnl_lebs
= UBIFS_MIN_JNL_LEBS
;
105 if (jnl_lebs
* c
->leb_size
> DEFAULT_MAX_JNL
)
106 jnl_lebs
= DEFAULT_MAX_JNL
/ c
->leb_size
;
109 * The log should be large enough to fit reference nodes for all bud
110 * LEBs. Because buds do not have to start from the beginning of LEBs
111 * (half of the LEB may contain committed data), the log should
112 * generally be larger, make it twice as large.
114 tmp
= 2 * (c
->ref_node_alsz
* jnl_lebs
) + c
->leb_size
- 1;
115 log_lebs
= tmp
/ c
->leb_size
;
116 /* Plus one LEB reserved for commit */
118 if (c
->leb_cnt
- min_leb_cnt
> 8) {
119 /* And some extra space to allow writes while committing */
124 max_buds
= jnl_lebs
- log_lebs
;
125 if (max_buds
< UBIFS_MIN_BUD_LEBS
)
126 max_buds
= UBIFS_MIN_BUD_LEBS
;
129 * Orphan nodes are stored in a separate area. One node can store a lot
130 * of orphan inode numbers, but when new orphan comes we just add a new
131 * orphan node. At some point the nodes are consolidated into one
134 orph_lebs
= UBIFS_MIN_ORPH_LEBS
;
135 if (c
->leb_cnt
- min_leb_cnt
> 1)
137 * For debugging purposes it is better to have at least 2
138 * orphan LEBs, because the orphan subsystem would need to do
139 * consolidations and would be stressed more.
143 main_lebs
= c
->leb_cnt
- UBIFS_SB_LEBS
- UBIFS_MST_LEBS
- log_lebs
;
144 main_lebs
-= orph_lebs
;
146 lpt_first
= UBIFS_LOG_LNUM
+ log_lebs
;
147 c
->lsave_cnt
= DEFAULT_LSAVE_CNT
;
148 c
->max_leb_cnt
= c
->leb_cnt
;
149 err
= ubifs_create_dflt_lpt(c
, &main_lebs
, lpt_first
, &lpt_lebs
,
154 dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first
,
155 lpt_first
+ lpt_lebs
- 1);
157 main_first
= c
->leb_cnt
- main_lebs
;
159 /* Create default superblock */
160 tmp
= ALIGN(UBIFS_SB_NODE_SZ
, c
->min_io_size
);
161 sup
= kzalloc(tmp
, GFP_KERNEL
);
165 tmp64
= (long long)max_buds
* c
->leb_size
;
167 sup_flags
|= UBIFS_FLG_BIGLPT
;
169 sup
->ch
.node_type
= UBIFS_SB_NODE
;
170 sup
->key_hash
= UBIFS_KEY_HASH_R5
;
171 sup
->flags
= cpu_to_le32(sup_flags
);
172 sup
->min_io_size
= cpu_to_le32(c
->min_io_size
);
173 sup
->leb_size
= cpu_to_le32(c
->leb_size
);
174 sup
->leb_cnt
= cpu_to_le32(c
->leb_cnt
);
175 sup
->max_leb_cnt
= cpu_to_le32(c
->max_leb_cnt
);
176 sup
->max_bud_bytes
= cpu_to_le64(tmp64
);
177 sup
->log_lebs
= cpu_to_le32(log_lebs
);
178 sup
->lpt_lebs
= cpu_to_le32(lpt_lebs
);
179 sup
->orph_lebs
= cpu_to_le32(orph_lebs
);
180 sup
->jhead_cnt
= cpu_to_le32(DEFAULT_JHEADS_CNT
);
181 sup
->fanout
= cpu_to_le32(DEFAULT_FANOUT
);
182 sup
->lsave_cnt
= cpu_to_le32(c
->lsave_cnt
);
183 sup
->fmt_version
= cpu_to_le32(UBIFS_FORMAT_VERSION
);
184 sup
->time_gran
= cpu_to_le32(DEFAULT_TIME_GRAN
);
185 if (c
->mount_opts
.override_compr
)
186 sup
->default_compr
= cpu_to_le16(c
->mount_opts
.compr_type
);
188 #if defined(CONFIG_UBIFS_FS_LZ4K)
189 sup
->default_compr
= cpu_to_le16(UBIFS_COMPR_LZ4K
);
191 sup
->default_compr
= cpu_to_le16(UBIFS_COMPR_LZO
);
195 generate_random_uuid(sup
->uuid
);
197 main_bytes
= (long long)main_lebs
* c
->leb_size
;
199 /*If the size of a volume is bigger than 1G, set rp_size to DEFAULT_MAX_RP_SIZE(16M).*/
200 if (main_bytes
>= UBIFS_ONE_GIGA
)
201 tmp64
= DEFAULT_MAX_RP_SIZE
;
205 sup
->rp_size
= cpu_to_le64(tmp64
);
206 sup
->rp_uid
= 10010; //VID_CCCI
207 sup
->ro_compat_version
= cpu_to_le32(UBIFS_RO_COMPAT_VERSION
);
209 err
= ubifs_write_node(c
, sup
, UBIFS_SB_NODE_SZ
, 0, 0);
214 dbg_gen("default superblock created at LEB 0:0");
216 /* Create default master node */
217 mst
= kzalloc(c
->mst_node_alsz
, GFP_KERNEL
);
221 mst
->ch
.node_type
= UBIFS_MST_NODE
;
222 mst
->log_lnum
= cpu_to_le32(UBIFS_LOG_LNUM
);
223 mst
->highest_inum
= cpu_to_le64(UBIFS_FIRST_INO
);
225 mst
->root_lnum
= cpu_to_le32(main_first
+ DEFAULT_IDX_LEB
);
227 tmp
= ubifs_idx_node_sz(c
, 1);
228 mst
->root_len
= cpu_to_le32(tmp
);
229 mst
->gc_lnum
= cpu_to_le32(main_first
+ DEFAULT_GC_LEB
);
230 mst
->ihead_lnum
= cpu_to_le32(main_first
+ DEFAULT_IDX_LEB
);
231 mst
->ihead_offs
= cpu_to_le32(ALIGN(tmp
, c
->min_io_size
));
232 mst
->index_size
= cpu_to_le64(ALIGN(tmp
, 8));
233 mst
->lpt_lnum
= cpu_to_le32(c
->lpt_lnum
);
234 mst
->lpt_offs
= cpu_to_le32(c
->lpt_offs
);
235 mst
->nhead_lnum
= cpu_to_le32(c
->nhead_lnum
);
236 mst
->nhead_offs
= cpu_to_le32(c
->nhead_offs
);
237 mst
->ltab_lnum
= cpu_to_le32(c
->ltab_lnum
);
238 mst
->ltab_offs
= cpu_to_le32(c
->ltab_offs
);
239 mst
->lsave_lnum
= cpu_to_le32(c
->lsave_lnum
);
240 mst
->lsave_offs
= cpu_to_le32(c
->lsave_offs
);
241 mst
->lscan_lnum
= cpu_to_le32(main_first
);
242 mst
->empty_lebs
= cpu_to_le32(main_lebs
- 2);
243 mst
->idx_lebs
= cpu_to_le32(1);
244 mst
->leb_cnt
= cpu_to_le32(c
->leb_cnt
);
246 /* Calculate lprops statistics */
248 tmp64
-= ALIGN(ubifs_idx_node_sz(c
, 1), c
->min_io_size
);
249 tmp64
-= ALIGN(UBIFS_INO_NODE_SZ
, c
->min_io_size
);
250 mst
->total_free
= cpu_to_le64(tmp64
);
252 tmp64
= ALIGN(ubifs_idx_node_sz(c
, 1), c
->min_io_size
);
253 ino_waste
= ALIGN(UBIFS_INO_NODE_SZ
, c
->min_io_size
) -
256 tmp64
-= ALIGN(ubifs_idx_node_sz(c
, 1), 8);
257 mst
->total_dirty
= cpu_to_le64(tmp64
);
259 /* The indexing LEB does not contribute to dark space */
260 tmp64
= ((long long)(c
->main_lebs
- 1) * c
->dark_wm
);
261 mst
->total_dark
= cpu_to_le64(tmp64
);
263 mst
->total_used
= cpu_to_le64(UBIFS_INO_NODE_SZ
);
265 err
= ubifs_write_node(c
, mst
, UBIFS_MST_NODE_SZ
, UBIFS_MST_LNUM
, 0);
270 err
= ubifs_write_node(c
, mst
, UBIFS_MST_NODE_SZ
, UBIFS_MST_LNUM
+ 1,
276 dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM
);
278 /* Create the root indexing node */
279 tmp
= ubifs_idx_node_sz(c
, 1);
280 idx
= kzalloc(ALIGN(tmp
, c
->min_io_size
), GFP_KERNEL
);
284 c
->key_fmt
= UBIFS_SIMPLE_KEY_FMT
;
285 c
->key_hash
= key_r5_hash
;
287 idx
->ch
.node_type
= UBIFS_IDX_NODE
;
288 idx
->child_cnt
= cpu_to_le16(1);
289 ino_key_init(c
, &key
, UBIFS_ROOT_INO
);
290 br
= ubifs_idx_branch(c
, idx
, 0);
291 key_write_idx(c
, &key
, &br
->key
);
292 br
->lnum
= cpu_to_le32(main_first
+ DEFAULT_DATA_LEB
);
293 br
->len
= cpu_to_le32(UBIFS_INO_NODE_SZ
);
294 err
= ubifs_write_node(c
, idx
, tmp
, main_first
+ DEFAULT_IDX_LEB
, 0);
299 dbg_gen("default root indexing node created LEB %d:0",
300 main_first
+ DEFAULT_IDX_LEB
);
302 /* Create default root inode */
303 tmp
= ALIGN(UBIFS_INO_NODE_SZ
, c
->min_io_size
);
304 ino
= kzalloc(tmp
, GFP_KERNEL
);
308 ino_key_init_flash(c
, &ino
->key
, UBIFS_ROOT_INO
);
309 ino
->ch
.node_type
= UBIFS_INO_NODE
;
310 ino
->creat_sqnum
= cpu_to_le64(++c
->max_sqnum
);
311 ino
->nlink
= cpu_to_le32(2);
312 tmp_le64
= cpu_to_le64(CURRENT_TIME_SEC
.tv_sec
);
313 ino
->atime_sec
= tmp_le64
;
314 ino
->ctime_sec
= tmp_le64
;
315 ino
->mtime_sec
= tmp_le64
;
319 ino
->mode
= cpu_to_le32(S_IFDIR
| S_IRUGO
| S_IWUSR
| S_IXUGO
);
320 ino
->size
= cpu_to_le64(UBIFS_INO_NODE_SZ
);
322 /* Set compression enabled by default */
323 ino
->flags
= cpu_to_le32(UBIFS_COMPR_FL
);
325 err
= ubifs_write_node(c
, ino
, UBIFS_INO_NODE_SZ
,
326 main_first
+ DEFAULT_DATA_LEB
, 0);
331 dbg_gen("root inode created at LEB %d:0",
332 main_first
+ DEFAULT_DATA_LEB
);
335 * The first node in the log has to be the commit start node. This is
336 * always the case during normal file-system operation. Write a fake
337 * commit start node to the log.
339 tmp
= ALIGN(UBIFS_CS_NODE_SZ
, c
->min_io_size
);
340 cs
= kzalloc(tmp
, GFP_KERNEL
);
344 cs
->ch
.node_type
= UBIFS_CS_NODE
;
345 err
= ubifs_write_node(c
, cs
, UBIFS_CS_NODE_SZ
, UBIFS_LOG_LNUM
, 0);
348 ubifs_msg("default file-system created");
353 * validate_sb - validate superblock node.
354 * @c: UBIFS file-system description object
355 * @sup: superblock node
357 * This function validates superblock node @sup. Since most of data was read
358 * from the superblock and stored in @c, the function validates fields in @c
359 * instead. Returns zero in case of success and %-EINVAL in case of validation
362 static int validate_sb(struct ubifs_info
*c
, struct ubifs_sb_node
*sup
)
365 int err
= 1, min_leb_cnt
;
372 if (sup
->key_fmt
!= UBIFS_SIMPLE_KEY_FMT
) {
377 if (le32_to_cpu(sup
->min_io_size
) != c
->min_io_size
) {
378 ubifs_err("min. I/O unit mismatch: %d in superblock, %d real",
379 le32_to_cpu(sup
->min_io_size
), c
->min_io_size
);
383 if (le32_to_cpu(sup
->leb_size
) != c
->leb_size
) {
384 ubifs_err("LEB size mismatch: %d in superblock, %d real",
385 le32_to_cpu(sup
->leb_size
), c
->leb_size
);
389 if (c
->log_lebs
< UBIFS_MIN_LOG_LEBS
||
390 c
->lpt_lebs
< UBIFS_MIN_LPT_LEBS
||
391 c
->orph_lebs
< UBIFS_MIN_ORPH_LEBS
||
392 c
->main_lebs
< UBIFS_MIN_MAIN_LEBS
) {
398 * Calculate minimum allowed amount of main area LEBs. This is very
399 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
400 * have just read from the superblock.
402 min_leb_cnt
= UBIFS_SB_LEBS
+ UBIFS_MST_LEBS
+ c
->log_lebs
;
403 min_leb_cnt
+= c
->lpt_lebs
+ c
->orph_lebs
+ c
->jhead_cnt
+ 6;
405 if (c
->leb_cnt
< min_leb_cnt
|| c
->leb_cnt
> c
->vi
.size
) {
406 ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, %d minimum required",
407 c
->leb_cnt
, c
->vi
.size
, min_leb_cnt
);
411 if (c
->max_leb_cnt
< c
->leb_cnt
) {
412 ubifs_err("max. LEB count %d less than LEB count %d",
413 c
->max_leb_cnt
, c
->leb_cnt
);
417 if (c
->main_lebs
< UBIFS_MIN_MAIN_LEBS
) {
418 ubifs_err("too few main LEBs count %d, must be at least %d",
419 c
->main_lebs
, UBIFS_MIN_MAIN_LEBS
);
423 max_bytes
= (long long)c
->leb_size
* UBIFS_MIN_BUD_LEBS
;
424 if (c
->max_bud_bytes
< max_bytes
) {
425 ubifs_err("too small journal (%lld bytes), must be at least %lld bytes",
426 c
->max_bud_bytes
, max_bytes
);
430 max_bytes
= (long long)c
->leb_size
* c
->main_lebs
;
431 if (c
->max_bud_bytes
> max_bytes
) {
432 ubifs_err("too large journal size (%lld bytes), only %lld bytes available in the main area",
433 c
->max_bud_bytes
, max_bytes
);
437 if (c
->jhead_cnt
< NONDATA_JHEADS_CNT
+ 1 ||
438 c
->jhead_cnt
> NONDATA_JHEADS_CNT
+ UBIFS_MAX_JHEADS
) {
443 if (c
->fanout
< UBIFS_MIN_FANOUT
||
444 ubifs_idx_node_sz(c
, c
->fanout
) > c
->leb_size
) {
449 if (c
->lsave_cnt
< 0 || (c
->lsave_cnt
> DEFAULT_LSAVE_CNT
&&
450 c
->lsave_cnt
> c
->max_leb_cnt
- UBIFS_SB_LEBS
- UBIFS_MST_LEBS
-
451 c
->log_lebs
- c
->lpt_lebs
- c
->orph_lebs
)) {
456 if (UBIFS_SB_LEBS
+ UBIFS_MST_LEBS
+ c
->log_lebs
+ c
->lpt_lebs
+
457 c
->orph_lebs
+ c
->main_lebs
!= c
->leb_cnt
) {
462 if (c
->default_compr
< 0 || c
->default_compr
>= UBIFS_COMPR_TYPES_CNT
) {
467 if (c
->rp_size
< 0 || max_bytes
< c
->rp_size
) {
472 if (le32_to_cpu(sup
->time_gran
) > 1000000000 ||
473 le32_to_cpu(sup
->time_gran
) < 1) {
481 ubifs_err("bad superblock, error %d", err
);
482 ubifs_dump_node(c
, sup
);
487 * ubifs_read_sb_node - read superblock node.
488 * @c: UBIFS file-system description object
490 * This function returns a pointer to the superblock node or a negative error
491 * code. Note, the user of this function is responsible of kfree()'ing the
492 * returned superblock buffer.
494 struct ubifs_sb_node
*ubifs_read_sb_node(struct ubifs_info
*c
)
496 struct ubifs_sb_node
*sup
;
499 sup
= kmalloc(ALIGN(UBIFS_SB_NODE_SZ
, c
->min_io_size
), GFP_NOFS
);
501 return ERR_PTR(-ENOMEM
);
503 err
= ubifs_read_node(c
, sup
, UBIFS_SB_NODE
, UBIFS_SB_NODE_SZ
,
514 * ubifs_write_sb_node - write superblock node.
515 * @c: UBIFS file-system description object
516 * @sup: superblock node read with 'ubifs_read_sb_node()'
518 * This function returns %0 on success and a negative error code on failure.
520 int ubifs_write_sb_node(struct ubifs_info
*c
, struct ubifs_sb_node
*sup
)
522 int len
= ALIGN(UBIFS_SB_NODE_SZ
, c
->min_io_size
);
524 ubifs_prepare_node(c
, sup
, UBIFS_SB_NODE_SZ
, 1);
525 return ubifs_leb_change(c
, UBIFS_SB_LNUM
, sup
, len
);
529 * ubifs_read_superblock - read superblock.
530 * @c: UBIFS file-system description object
532 * This function finds, reads and checks the superblock. If an empty UBI volume
533 * is being mounted, this function creates default superblock. Returns zero in
534 * case of success, and a negative error code in case of failure.
536 int ubifs_read_superblock(struct ubifs_info
*c
)
539 struct ubifs_sb_node
*sup
;
542 err
= create_default_filesystem(c
);
547 sup
= ubifs_read_sb_node(c
);
551 c
->fmt_version
= le32_to_cpu(sup
->fmt_version
);
552 c
->ro_compat_version
= le32_to_cpu(sup
->ro_compat_version
);
555 * The software supports all previous versions but not future versions,
556 * due to the unavailability of time-travelling equipment.
558 if (c
->fmt_version
> UBIFS_FORMAT_VERSION
) {
559 ubifs_assert(!c
->ro_media
|| c
->ro_mount
);
561 c
->ro_compat_version
> UBIFS_RO_COMPAT_VERSION
) {
562 ubifs_err("on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d",
563 c
->fmt_version
, c
->ro_compat_version
,
564 UBIFS_FORMAT_VERSION
,
565 UBIFS_RO_COMPAT_VERSION
);
566 if (c
->ro_compat_version
<= UBIFS_RO_COMPAT_VERSION
) {
567 ubifs_msg("only R/O mounting is possible");
575 * The FS is mounted R/O, and the media format is
576 * R/O-compatible with the UBIFS implementation, so we can
582 if (c
->fmt_version
< 3) {
583 ubifs_err("on-flash format version %d is not supported",
589 switch (sup
->key_hash
) {
590 case UBIFS_KEY_HASH_R5
:
591 c
->key_hash
= key_r5_hash
;
592 c
->key_hash_type
= UBIFS_KEY_HASH_R5
;
595 case UBIFS_KEY_HASH_TEST
:
596 c
->key_hash
= key_test_hash
;
597 c
->key_hash_type
= UBIFS_KEY_HASH_TEST
;
601 c
->key_fmt
= sup
->key_fmt
;
603 switch (c
->key_fmt
) {
604 case UBIFS_SIMPLE_KEY_FMT
:
605 c
->key_len
= UBIFS_SK_LEN
;
608 ubifs_err("unsupported key format");
613 c
->leb_cnt
= le32_to_cpu(sup
->leb_cnt
);
614 c
->max_leb_cnt
= le32_to_cpu(sup
->max_leb_cnt
);
615 c
->max_bud_bytes
= le64_to_cpu(sup
->max_bud_bytes
);
616 c
->log_lebs
= le32_to_cpu(sup
->log_lebs
);
617 c
->lpt_lebs
= le32_to_cpu(sup
->lpt_lebs
);
618 c
->orph_lebs
= le32_to_cpu(sup
->orph_lebs
);
619 c
->jhead_cnt
= le32_to_cpu(sup
->jhead_cnt
) + NONDATA_JHEADS_CNT
;
620 c
->fanout
= le32_to_cpu(sup
->fanout
);
621 c
->lsave_cnt
= le32_to_cpu(sup
->lsave_cnt
);
622 c
->rp_size
= le64_to_cpu(sup
->rp_size
);
623 c
->rp_uid
= make_kuid(&init_user_ns
, le32_to_cpu(sup
->rp_uid
));
624 c
->rp_gid
= make_kgid(&init_user_ns
, le32_to_cpu(sup
->rp_gid
));
625 sup_flags
= le32_to_cpu(sup
->flags
);
626 if (!c
->mount_opts
.override_compr
)
627 c
->default_compr
= le16_to_cpu(sup
->default_compr
);
629 c
->vfs_sb
->s_time_gran
= le32_to_cpu(sup
->time_gran
);
630 memcpy(&c
->uuid
, &sup
->uuid
, 16);
631 c
->big_lpt
= !!(sup_flags
& UBIFS_FLG_BIGLPT
);
632 c
->space_fixup
= !!(sup_flags
& UBIFS_FLG_SPACE_FIXUP
);
634 /* Automatically increase file system size to the maximum size */
635 c
->old_leb_cnt
= c
->leb_cnt
;
636 if (c
->leb_cnt
< c
->vi
.size
&& c
->leb_cnt
< c
->max_leb_cnt
) {
637 c
->leb_cnt
= min_t(int, c
->max_leb_cnt
, c
->vi
.size
);
639 dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
640 c
->old_leb_cnt
, c
->leb_cnt
);
642 dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
643 c
->old_leb_cnt
, c
->leb_cnt
);
644 sup
->leb_cnt
= cpu_to_le32(c
->leb_cnt
);
645 err
= ubifs_write_sb_node(c
, sup
);
648 c
->old_leb_cnt
= c
->leb_cnt
;
652 c
->log_bytes
= (long long)c
->log_lebs
* c
->leb_size
;
653 c
->log_last
= UBIFS_LOG_LNUM
+ c
->log_lebs
- 1;
654 c
->lpt_first
= UBIFS_LOG_LNUM
+ c
->log_lebs
;
655 c
->lpt_last
= c
->lpt_first
+ c
->lpt_lebs
- 1;
656 c
->orph_first
= c
->lpt_last
+ 1;
657 c
->orph_last
= c
->orph_first
+ c
->orph_lebs
- 1;
658 c
->main_lebs
= c
->leb_cnt
- UBIFS_SB_LEBS
- UBIFS_MST_LEBS
;
659 c
->main_lebs
-= c
->log_lebs
+ c
->lpt_lebs
+ c
->orph_lebs
;
660 c
->main_first
= c
->leb_cnt
- c
->main_lebs
;
662 err
= validate_sb(c
, sup
);
669 * fixup_leb - fixup/unmap an LEB containing free space.
670 * @c: UBIFS file-system description object
671 * @lnum: the LEB number to fix up
672 * @len: number of used bytes in LEB (starting at offset 0)
674 * This function reads the contents of the given LEB number @lnum, then fixes
675 * it up, so that empty min. I/O units in the end of LEB are actually erased on
676 * flash (rather than being just all-0xff real data). If the LEB is completely
677 * empty, it is simply unmapped.
679 static int fixup_leb(struct ubifs_info
*c
, int lnum
, int len
)
683 ubifs_assert(len
>= 0);
684 ubifs_assert(len
% c
->min_io_size
== 0);
685 ubifs_assert(len
< c
->leb_size
);
688 dbg_mnt("unmap empty LEB %d", lnum
);
689 return ubifs_leb_unmap(c
, lnum
);
692 dbg_mnt("fixup LEB %d, data len %d", lnum
, len
);
693 err
= ubifs_leb_read(c
, lnum
, c
->sbuf
, 0, len
, 1);
697 return ubifs_leb_change(c
, lnum
, c
->sbuf
, len
);
701 * fixup_free_space - find & remap all LEBs containing free space.
702 * @c: UBIFS file-system description object
704 * This function walks through all LEBs in the filesystem and fiexes up those
705 * containing free/empty space.
707 static int fixup_free_space(struct ubifs_info
*c
)
710 struct ubifs_lprops
*lprops
;
714 /* Fixup LEBs in the master area */
715 for (lnum
= UBIFS_MST_LNUM
; lnum
< UBIFS_LOG_LNUM
; lnum
++) {
716 err
= fixup_leb(c
, lnum
, c
->mst_offs
+ c
->mst_node_alsz
);
721 /* Unmap unused log LEBs */
722 lnum
= ubifs_next_log_lnum(c
, c
->lhead_lnum
);
723 while (lnum
!= c
->ltail_lnum
) {
724 err
= fixup_leb(c
, lnum
, 0);
727 lnum
= ubifs_next_log_lnum(c
, lnum
);
731 * Fixup the log head which contains the only a CS node at the
734 err
= fixup_leb(c
, c
->lhead_lnum
,
735 ALIGN(UBIFS_CS_NODE_SZ
, c
->min_io_size
));
739 /* Fixup LEBs in the LPT area */
740 for (lnum
= c
->lpt_first
; lnum
<= c
->lpt_last
; lnum
++) {
741 int free
= c
->ltab
[lnum
- c
->lpt_first
].free
;
744 err
= fixup_leb(c
, lnum
, c
->leb_size
- free
);
750 /* Unmap LEBs in the orphans area */
751 for (lnum
= c
->orph_first
; lnum
<= c
->orph_last
; lnum
++) {
752 err
= fixup_leb(c
, lnum
, 0);
757 /* Fixup LEBs in the main area */
758 for (lnum
= c
->main_first
; lnum
< c
->leb_cnt
; lnum
++) {
759 lprops
= ubifs_lpt_lookup(c
, lnum
);
760 if (IS_ERR(lprops
)) {
761 err
= PTR_ERR(lprops
);
765 if (lprops
->free
> 0) {
766 err
= fixup_leb(c
, lnum
, c
->leb_size
- lprops
->free
);
773 ubifs_release_lprops(c
);
778 * ubifs_fixup_free_space - find & fix all LEBs with free space.
779 * @c: UBIFS file-system description object
781 * This function fixes up LEBs containing free space on first mount, if the
782 * appropriate flag was set when the FS was created. Each LEB with one or more
783 * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure
784 * the free space is actually erased. E.g., this is necessary for some NAND
785 * chips, since the free space may have been programmed like real "0xff" data
786 * (generating a non-0xff ECC), causing future writes to the not-really-erased
787 * NAND pages to behave badly. After the space is fixed up, the superblock flag
788 * is cleared, so that this is skipped for all future mounts.
790 int ubifs_fixup_free_space(struct ubifs_info
*c
)
793 struct ubifs_sb_node
*sup
;
795 ubifs_assert(c
->space_fixup
);
796 ubifs_assert(!c
->ro_mount
);
798 ubifs_msg("start fixing up free space");
800 err
= fixup_free_space(c
);
804 sup
= ubifs_read_sb_node(c
);
808 /* Free-space fixup is no longer required */
810 sup
->flags
&= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP
);
812 err
= ubifs_write_sb_node(c
, sup
);
817 ubifs_msg("free space fixup complete");