1 // SPDX-License-Identifier: GPL-2.0-only
3 * This file is part of UBIFS.
5 * Copyright (C) 2006-2008 Nokia Corporation.
7 * Authors: Artem Bityutskiy (Битюцкий Артём)
12 * This file implements UBIFS superblock. The superblock is stored at the first
13 * LEB of the volume and is never changed by UBIFS. Only user-space tools may
14 * change it. The superblock node mostly contains geometry information.
18 #include <linux/slab.h>
19 #include <linux/math64.h>
20 #include <linux/uuid.h>
23 * Default journal size in logical eraseblocks as a percent of total
26 #define DEFAULT_JNL_PERCENT 5
28 /* Default maximum journal size in bytes */
29 #define DEFAULT_MAX_JNL (32*1024*1024)
31 /* Default indexing tree fanout */
32 #define DEFAULT_FANOUT 8
34 /* Default number of data journal heads */
35 #define DEFAULT_JHEADS_CNT 1
37 /* Default positions of different LEBs in the main area */
38 #define DEFAULT_IDX_LEB 0
39 #define DEFAULT_DATA_LEB 1
40 #define DEFAULT_GC_LEB 2
42 /* Default number of LEB numbers in LPT's save table */
43 #define DEFAULT_LSAVE_CNT 256
45 /* Default reserved pool size as a percent of maximum free space */
46 #define DEFAULT_RP_PERCENT 5
48 /* The default maximum size of reserved pool in bytes */
49 #define DEFAULT_MAX_RP_SIZE (5*1024*1024)
51 /* Default time granularity in nanoseconds */
52 #define DEFAULT_TIME_GRAN 1000000000
54 static int get_default_compressor(struct ubifs_info *c)
56 if (ubifs_compr_present(c, UBIFS_COMPR_LZO))
57 return UBIFS_COMPR_LZO;
59 if (ubifs_compr_present(c, UBIFS_COMPR_ZLIB))
60 return UBIFS_COMPR_ZLIB;
62 return UBIFS_COMPR_NONE;
66 * create_default_filesystem - format empty UBI volume.
67 * @c: UBIFS file-system description object
69 * This function creates default empty file-system. Returns zero in case of
70 * success and a negative error code in case of failure.
72 static int create_default_filesystem(struct ubifs_info *c)
74 struct ubifs_sb_node *sup;
75 struct ubifs_mst_node *mst;
76 struct ubifs_idx_node *idx;
77 struct ubifs_branch *br;
78 struct ubifs_ino_node *ino;
79 struct ubifs_cs_node *cs;
81 int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first;
82 int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0;
83 int min_leb_cnt = UBIFS_MIN_LEB_CNT;
85 long long tmp64, main_bytes;
89 u8 hash[UBIFS_HASH_ARR_SZ];
90 u8 hash_lpt[UBIFS_HASH_ARR_SZ];
92 /* Some functions called from here depend on the @c->key_len filed */
93 c->key_len = UBIFS_SK_LEN;
96 * First of all, we have to calculate default file-system geometry -
97 * log size, journal size, etc.
99 if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT)
100 /* We can first multiply then divide and have no overflow */
101 jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100;
103 jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
105 if (jnl_lebs < UBIFS_MIN_JNL_LEBS)
106 jnl_lebs = UBIFS_MIN_JNL_LEBS;
107 if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL)
108 jnl_lebs = DEFAULT_MAX_JNL / c->leb_size;
111 * The log should be large enough to fit reference nodes for all bud
112 * LEBs. Because buds do not have to start from the beginning of LEBs
113 * (half of the LEB may contain committed data), the log should
114 * generally be larger, make it twice as large.
116 tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1;
117 log_lebs = tmp / c->leb_size;
118 /* Plus one LEB reserved for commit */
120 if (c->leb_cnt - min_leb_cnt > 8) {
121 /* And some extra space to allow writes while committing */
126 max_buds = jnl_lebs - log_lebs;
127 if (max_buds < UBIFS_MIN_BUD_LEBS)
128 max_buds = UBIFS_MIN_BUD_LEBS;
131 * Orphan nodes are stored in a separate area. One node can store a lot
132 * of orphan inode numbers, but when new orphan comes we just add a new
133 * orphan node. At some point the nodes are consolidated into one
136 orph_lebs = UBIFS_MIN_ORPH_LEBS;
137 if (c->leb_cnt - min_leb_cnt > 1)
139 * For debugging purposes it is better to have at least 2
140 * orphan LEBs, because the orphan subsystem would need to do
141 * consolidations and would be stressed more.
145 main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
146 main_lebs -= orph_lebs;
148 lpt_first = UBIFS_LOG_LNUM + log_lebs;
149 c->lsave_cnt = DEFAULT_LSAVE_CNT;
150 c->max_leb_cnt = c->leb_cnt;
151 err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
156 dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
157 lpt_first + lpt_lebs - 1);
159 main_first = c->leb_cnt - main_lebs;
161 sup = kzalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_KERNEL);
162 mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
163 idx_node_size = ubifs_idx_node_sz(c, 1);
164 idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
165 ino = kzalloc(ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size), GFP_KERNEL);
166 cs = kzalloc(ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size), GFP_KERNEL);
168 if (!sup || !mst || !idx || !ino || !cs) {
173 /* Create default superblock */
175 tmp64 = (long long)max_buds * c->leb_size;
177 sup_flags |= UBIFS_FLG_BIGLPT;
178 sup_flags |= UBIFS_FLG_DOUBLE_HASH;
180 if (ubifs_authenticated(c)) {
181 sup_flags |= UBIFS_FLG_AUTHENTICATION;
182 sup->hash_algo = cpu_to_le16(c->auth_hash_algo);
183 err = ubifs_hmac_wkm(c, sup->hmac_wkm);
187 sup->hash_algo = 0xffff;
190 sup->ch.node_type = UBIFS_SB_NODE;
191 sup->key_hash = UBIFS_KEY_HASH_R5;
192 sup->flags = cpu_to_le32(sup_flags);
193 sup->min_io_size = cpu_to_le32(c->min_io_size);
194 sup->leb_size = cpu_to_le32(c->leb_size);
195 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
196 sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt);
197 sup->max_bud_bytes = cpu_to_le64(tmp64);
198 sup->log_lebs = cpu_to_le32(log_lebs);
199 sup->lpt_lebs = cpu_to_le32(lpt_lebs);
200 sup->orph_lebs = cpu_to_le32(orph_lebs);
201 sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT);
202 sup->fanout = cpu_to_le32(DEFAULT_FANOUT);
203 sup->lsave_cnt = cpu_to_le32(c->lsave_cnt);
204 sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION);
205 sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN);
206 if (c->mount_opts.override_compr)
207 sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
209 sup->default_compr = cpu_to_le16(get_default_compressor(c));
211 generate_random_uuid(sup->uuid);
213 main_bytes = (long long)main_lebs * c->leb_size;
214 tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100);
215 if (tmp64 > DEFAULT_MAX_RP_SIZE)
216 tmp64 = DEFAULT_MAX_RP_SIZE;
217 sup->rp_size = cpu_to_le64(tmp64);
218 sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION);
220 dbg_gen("default superblock created at LEB 0:0");
222 /* Create default master node */
224 mst->ch.node_type = UBIFS_MST_NODE;
225 mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM);
226 mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
228 mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
230 tmp = ubifs_idx_node_sz(c, 1);
231 mst->root_len = cpu_to_le32(tmp);
232 mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB);
233 mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
234 mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size));
235 mst->index_size = cpu_to_le64(ALIGN(tmp, 8));
236 mst->lpt_lnum = cpu_to_le32(c->lpt_lnum);
237 mst->lpt_offs = cpu_to_le32(c->lpt_offs);
238 mst->nhead_lnum = cpu_to_le32(c->nhead_lnum);
239 mst->nhead_offs = cpu_to_le32(c->nhead_offs);
240 mst->ltab_lnum = cpu_to_le32(c->ltab_lnum);
241 mst->ltab_offs = cpu_to_le32(c->ltab_offs);
242 mst->lsave_lnum = cpu_to_le32(c->lsave_lnum);
243 mst->lsave_offs = cpu_to_le32(c->lsave_offs);
244 mst->lscan_lnum = cpu_to_le32(main_first);
245 mst->empty_lebs = cpu_to_le32(main_lebs - 2);
246 mst->idx_lebs = cpu_to_le32(1);
247 mst->leb_cnt = cpu_to_le32(c->leb_cnt);
248 ubifs_copy_hash(c, hash_lpt, mst->hash_lpt);
250 /* Calculate lprops statistics */
252 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
253 tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
254 mst->total_free = cpu_to_le64(tmp64);
256 tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
257 ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
260 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
261 mst->total_dirty = cpu_to_le64(tmp64);
263 /* The indexing LEB does not contribute to dark space */
264 tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm);
265 mst->total_dark = cpu_to_le64(tmp64);
267 mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
269 dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
271 /* Create the root indexing node */
273 c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
274 c->key_hash = key_r5_hash;
276 idx->ch.node_type = UBIFS_IDX_NODE;
277 idx->child_cnt = cpu_to_le16(1);
278 ino_key_init(c, &key, UBIFS_ROOT_INO);
279 br = ubifs_idx_branch(c, idx, 0);
280 key_write_idx(c, &key, &br->key);
281 br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
282 br->len = cpu_to_le32(UBIFS_INO_NODE_SZ);
284 dbg_gen("default root indexing node created LEB %d:0",
285 main_first + DEFAULT_IDX_LEB);
287 /* Create default root inode */
289 ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
290 ino->ch.node_type = UBIFS_INO_NODE;
291 ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
292 ino->nlink = cpu_to_le32(2);
294 ktime_get_real_ts64(&ts);
295 ts = timespec64_trunc(ts, DEFAULT_TIME_GRAN);
296 tmp_le64 = cpu_to_le64(ts.tv_sec);
297 ino->atime_sec = tmp_le64;
298 ino->ctime_sec = tmp_le64;
299 ino->mtime_sec = tmp_le64;
300 tmp_le32 = cpu_to_le32(ts.tv_nsec);
301 ino->atime_nsec = tmp_le32;
302 ino->ctime_nsec = tmp_le32;
303 ino->mtime_nsec = tmp_le32;
304 ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
305 ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
307 /* Set compression enabled by default */
308 ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
310 dbg_gen("root inode created at LEB %d:0",
311 main_first + DEFAULT_DATA_LEB);
314 * The first node in the log has to be the commit start node. This is
315 * always the case during normal file-system operation. Write a fake
316 * commit start node to the log.
319 cs->ch.node_type = UBIFS_CS_NODE;
321 err = ubifs_write_node_hmac(c, sup, UBIFS_SB_NODE_SZ, 0, 0,
322 offsetof(struct ubifs_sb_node, hmac));
326 err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
327 main_first + DEFAULT_DATA_LEB, 0);
331 ubifs_node_calc_hash(c, ino, hash);
332 ubifs_copy_hash(c, hash, ubifs_branch_hash(c, br));
334 err = ubifs_write_node(c, idx, idx_node_size, main_first + DEFAULT_IDX_LEB, 0);
338 ubifs_node_calc_hash(c, idx, hash);
339 ubifs_copy_hash(c, hash, mst->hash_root_idx);
341 err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0,
342 offsetof(struct ubifs_mst_node, hmac));
346 err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1,
347 0, offsetof(struct ubifs_mst_node, hmac));
351 err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0);
355 ubifs_msg(c, "default file-system created");
369 * validate_sb - validate superblock node.
370 * @c: UBIFS file-system description object
371 * @sup: superblock node
373 * This function validates superblock node @sup. Since most of data was read
374 * from the superblock and stored in @c, the function validates fields in @c
375 * instead. Returns zero in case of success and %-EINVAL in case of validation
378 static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
381 int err = 1, min_leb_cnt;
388 if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
393 if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
394 ubifs_err(c, "min. I/O unit mismatch: %d in superblock, %d real",
395 le32_to_cpu(sup->min_io_size), c->min_io_size);
399 if (le32_to_cpu(sup->leb_size) != c->leb_size) {
400 ubifs_err(c, "LEB size mismatch: %d in superblock, %d real",
401 le32_to_cpu(sup->leb_size), c->leb_size);
405 if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
406 c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
407 c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
408 c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
414 * Calculate minimum allowed amount of main area LEBs. This is very
415 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
416 * have just read from the superblock.
418 min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
419 min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
421 if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
422 ubifs_err(c, "bad LEB count: %d in superblock, %d on UBI volume, %d minimum required",
423 c->leb_cnt, c->vi.size, min_leb_cnt);
427 if (c->max_leb_cnt < c->leb_cnt) {
428 ubifs_err(c, "max. LEB count %d less than LEB count %d",
429 c->max_leb_cnt, c->leb_cnt);
433 if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
434 ubifs_err(c, "too few main LEBs count %d, must be at least %d",
435 c->main_lebs, UBIFS_MIN_MAIN_LEBS);
439 max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS;
440 if (c->max_bud_bytes < max_bytes) {
441 ubifs_err(c, "too small journal (%lld bytes), must be at least %lld bytes",
442 c->max_bud_bytes, max_bytes);
446 max_bytes = (long long)c->leb_size * c->main_lebs;
447 if (c->max_bud_bytes > max_bytes) {
448 ubifs_err(c, "too large journal size (%lld bytes), only %lld bytes available in the main area",
449 c->max_bud_bytes, max_bytes);
453 if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
454 c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
459 if (c->fanout < UBIFS_MIN_FANOUT ||
460 ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
465 if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
466 c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
467 c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
472 if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
473 c->orph_lebs + c->main_lebs != c->leb_cnt) {
478 if (c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
483 if (c->rp_size < 0 || max_bytes < c->rp_size) {
488 if (le32_to_cpu(sup->time_gran) > 1000000000 ||
489 le32_to_cpu(sup->time_gran) < 1) {
494 if (!c->double_hash && c->fmt_version >= 5) {
499 if (c->encrypted && c->fmt_version < 5) {
507 ubifs_err(c, "bad superblock, error %d", err);
508 ubifs_dump_node(c, sup);
513 * ubifs_read_sb_node - read superblock node.
514 * @c: UBIFS file-system description object
516 * This function returns a pointer to the superblock node or a negative error
517 * code. Note, the user of this function is responsible of kfree()'ing the
518 * returned superblock buffer.
520 static struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
522 struct ubifs_sb_node *sup;
525 sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
527 return ERR_PTR(-ENOMEM);
529 err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
539 static int authenticate_sb_node(struct ubifs_info *c,
540 const struct ubifs_sb_node *sup)
542 unsigned int sup_flags = le32_to_cpu(sup->flags);
543 u8 hmac_wkm[UBIFS_HMAC_ARR_SZ];
544 int authenticated = !!(sup_flags & UBIFS_FLG_AUTHENTICATION);
548 if (c->authenticated && !authenticated) {
549 ubifs_err(c, "authenticated FS forced, but found FS without authentication");
553 if (!c->authenticated && authenticated) {
554 ubifs_err(c, "authenticated FS found, but no key given");
558 ubifs_msg(c, "Mounting in %sauthenticated mode",
559 c->authenticated ? "" : "un");
561 if (!c->authenticated)
564 if (!IS_ENABLED(CONFIG_UBIFS_FS_AUTHENTICATION))
567 hash_algo = le16_to_cpu(sup->hash_algo);
568 if (hash_algo >= HASH_ALGO__LAST) {
569 ubifs_err(c, "superblock uses unknown hash algo %d",
574 if (strcmp(hash_algo_name[hash_algo], c->auth_hash_name)) {
575 ubifs_err(c, "This filesystem uses %s for hashing,"
576 " but %s is specified", hash_algo_name[hash_algo],
582 * The super block node can either be authenticated by a HMAC or
583 * by a signature in a ubifs_sig_node directly following the
584 * super block node to support offline image creation.
586 if (ubifs_hmac_zero(c, sup->hmac)) {
587 err = ubifs_sb_verify_signature(c, sup);
589 err = ubifs_hmac_wkm(c, hmac_wkm);
592 if (ubifs_check_hmac(c, hmac_wkm, sup->hmac_wkm)) {
593 ubifs_err(c, "provided key does not fit");
596 err = ubifs_node_verify_hmac(c, sup, sizeof(*sup),
597 offsetof(struct ubifs_sb_node,
602 ubifs_err(c, "Failed to authenticate superblock: %d", err);
608 * ubifs_write_sb_node - write superblock node.
609 * @c: UBIFS file-system description object
610 * @sup: superblock node read with 'ubifs_read_sb_node()'
612 * This function returns %0 on success and a negative error code on failure.
614 int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
616 int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
619 err = ubifs_prepare_node_hmac(c, sup, UBIFS_SB_NODE_SZ,
620 offsetof(struct ubifs_sb_node, hmac), 1);
624 return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len);
628 * ubifs_read_superblock - read superblock.
629 * @c: UBIFS file-system description object
631 * This function finds, reads and checks the superblock. If an empty UBI volume
632 * is being mounted, this function creates default superblock. Returns zero in
633 * case of success, and a negative error code in case of failure.
635 int ubifs_read_superblock(struct ubifs_info *c)
638 struct ubifs_sb_node *sup;
641 err = create_default_filesystem(c);
646 sup = ubifs_read_sb_node(c);
652 c->fmt_version = le32_to_cpu(sup->fmt_version);
653 c->ro_compat_version = le32_to_cpu(sup->ro_compat_version);
656 * The software supports all previous versions but not future versions,
657 * due to the unavailability of time-travelling equipment.
659 if (c->fmt_version > UBIFS_FORMAT_VERSION) {
660 ubifs_assert(c, !c->ro_media || c->ro_mount);
662 c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) {
663 ubifs_err(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d",
664 c->fmt_version, c->ro_compat_version,
665 UBIFS_FORMAT_VERSION,
666 UBIFS_RO_COMPAT_VERSION);
667 if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) {
668 ubifs_msg(c, "only R/O mounting is possible");
676 * The FS is mounted R/O, and the media format is
677 * R/O-compatible with the UBIFS implementation, so we can
683 if (c->fmt_version < 3) {
684 ubifs_err(c, "on-flash format version %d is not supported",
690 switch (sup->key_hash) {
691 case UBIFS_KEY_HASH_R5:
692 c->key_hash = key_r5_hash;
693 c->key_hash_type = UBIFS_KEY_HASH_R5;
696 case UBIFS_KEY_HASH_TEST:
697 c->key_hash = key_test_hash;
698 c->key_hash_type = UBIFS_KEY_HASH_TEST;
702 c->key_fmt = sup->key_fmt;
704 switch (c->key_fmt) {
705 case UBIFS_SIMPLE_KEY_FMT:
706 c->key_len = UBIFS_SK_LEN;
709 ubifs_err(c, "unsupported key format");
714 c->leb_cnt = le32_to_cpu(sup->leb_cnt);
715 c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt);
716 c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
717 c->log_lebs = le32_to_cpu(sup->log_lebs);
718 c->lpt_lebs = le32_to_cpu(sup->lpt_lebs);
719 c->orph_lebs = le32_to_cpu(sup->orph_lebs);
720 c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
721 c->fanout = le32_to_cpu(sup->fanout);
722 c->lsave_cnt = le32_to_cpu(sup->lsave_cnt);
723 c->rp_size = le64_to_cpu(sup->rp_size);
724 c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid));
725 c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid));
726 sup_flags = le32_to_cpu(sup->flags);
727 if (!c->mount_opts.override_compr)
728 c->default_compr = le16_to_cpu(sup->default_compr);
730 c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
731 memcpy(&c->uuid, &sup->uuid, 16);
732 c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
733 c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP);
734 c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH);
735 c->encrypted = !!(sup_flags & UBIFS_FLG_ENCRYPTION);
737 err = authenticate_sb_node(c, sup);
741 if ((sup_flags & ~UBIFS_FLG_MASK) != 0) {
742 ubifs_err(c, "Unknown feature flags found: %#x",
743 sup_flags & ~UBIFS_FLG_MASK);
748 if (!IS_ENABLED(CONFIG_FS_ENCRYPTION) && c->encrypted) {
749 ubifs_err(c, "file system contains encrypted files but UBIFS"
750 " was built without crypto support.");
755 /* Automatically increase file system size to the maximum size */
756 if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
757 int old_leb_cnt = c->leb_cnt;
759 c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
760 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
762 c->superblock_need_write = 1;
764 dbg_mnt("Auto resizing from %d LEBs to %d LEBs",
765 old_leb_cnt, c->leb_cnt);
768 c->log_bytes = (long long)c->log_lebs * c->leb_size;
769 c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1;
770 c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs;
771 c->lpt_last = c->lpt_first + c->lpt_lebs - 1;
772 c->orph_first = c->lpt_last + 1;
773 c->orph_last = c->orph_first + c->orph_lebs - 1;
774 c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS;
775 c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs;
776 c->main_first = c->leb_cnt - c->main_lebs;
778 err = validate_sb(c, sup);
784 * fixup_leb - fixup/unmap an LEB containing free space.
785 * @c: UBIFS file-system description object
786 * @lnum: the LEB number to fix up
787 * @len: number of used bytes in LEB (starting at offset 0)
789 * This function reads the contents of the given LEB number @lnum, then fixes
790 * it up, so that empty min. I/O units in the end of LEB are actually erased on
791 * flash (rather than being just all-0xff real data). If the LEB is completely
792 * empty, it is simply unmapped.
794 static int fixup_leb(struct ubifs_info *c, int lnum, int len)
798 ubifs_assert(c, len >= 0);
799 ubifs_assert(c, len % c->min_io_size == 0);
800 ubifs_assert(c, len < c->leb_size);
803 dbg_mnt("unmap empty LEB %d", lnum);
804 return ubifs_leb_unmap(c, lnum);
807 dbg_mnt("fixup LEB %d, data len %d", lnum, len);
808 err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1);
812 return ubifs_leb_change(c, lnum, c->sbuf, len);
816 * fixup_free_space - find & remap all LEBs containing free space.
817 * @c: UBIFS file-system description object
819 * This function walks through all LEBs in the filesystem and fiexes up those
820 * containing free/empty space.
822 static int fixup_free_space(struct ubifs_info *c)
825 struct ubifs_lprops *lprops;
829 /* Fixup LEBs in the master area */
830 for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) {
831 err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz);
836 /* Unmap unused log LEBs */
837 lnum = ubifs_next_log_lnum(c, c->lhead_lnum);
838 while (lnum != c->ltail_lnum) {
839 err = fixup_leb(c, lnum, 0);
842 lnum = ubifs_next_log_lnum(c, lnum);
846 * Fixup the log head which contains the only a CS node at the
849 err = fixup_leb(c, c->lhead_lnum,
850 ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size));
854 /* Fixup LEBs in the LPT area */
855 for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) {
856 int free = c->ltab[lnum - c->lpt_first].free;
859 err = fixup_leb(c, lnum, c->leb_size - free);
865 /* Unmap LEBs in the orphans area */
866 for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) {
867 err = fixup_leb(c, lnum, 0);
872 /* Fixup LEBs in the main area */
873 for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) {
874 lprops = ubifs_lpt_lookup(c, lnum);
875 if (IS_ERR(lprops)) {
876 err = PTR_ERR(lprops);
880 if (lprops->free > 0) {
881 err = fixup_leb(c, lnum, c->leb_size - lprops->free);
888 ubifs_release_lprops(c);
893 * ubifs_fixup_free_space - find & fix all LEBs with free space.
894 * @c: UBIFS file-system description object
896 * This function fixes up LEBs containing free space on first mount, if the
897 * appropriate flag was set when the FS was created. Each LEB with one or more
898 * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure
899 * the free space is actually erased. E.g., this is necessary for some NAND
900 * chips, since the free space may have been programmed like real "0xff" data
901 * (generating a non-0xff ECC), causing future writes to the not-really-erased
902 * NAND pages to behave badly. After the space is fixed up, the superblock flag
903 * is cleared, so that this is skipped for all future mounts.
905 int ubifs_fixup_free_space(struct ubifs_info *c)
908 struct ubifs_sb_node *sup = c->sup_node;
910 ubifs_assert(c, c->space_fixup);
911 ubifs_assert(c, !c->ro_mount);
913 ubifs_msg(c, "start fixing up free space");
915 err = fixup_free_space(c);
919 /* Free-space fixup is no longer required */
921 sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP);
923 c->superblock_need_write = 1;
925 ubifs_msg(c, "free space fixup complete");
929 int ubifs_enable_encryption(struct ubifs_info *c)
932 struct ubifs_sb_node *sup = c->sup_node;
934 if (!IS_ENABLED(CONFIG_FS_ENCRYPTION))
940 if (c->ro_mount || c->ro_media)
943 if (c->fmt_version < 5) {
944 ubifs_err(c, "on-flash format version 5 is needed for encryption");
948 sup->flags |= cpu_to_le32(UBIFS_FLG_ENCRYPTION);
950 err = ubifs_write_sb_node(c, sup);