2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation.
6 * SPDX-License-Identifier: GPL-2.0+
8 * Authors: Artem Bityutskiy (Битюцкий Артём)
13 * This file implements UBIFS superblock. The superblock is stored at the first
14 * LEB of the volume and is never changed by UBIFS. Only user-space tools may
15 * change it. The superblock node mostly contains geometry information.
21 #include <linux/slab.h>
22 #include <linux/random.h>
23 #include <linux/math64.h>
26 #include <linux/compat.h>
27 #include <linux/err.h>
28 #include <ubi_uboot.h>
29 #include <linux/stat.h>
33 * Default journal size in logical eraseblocks as a percent of total
36 #define DEFAULT_JNL_PERCENT 5
38 /* Default maximum journal size in bytes */
39 #define DEFAULT_MAX_JNL (32*1024*1024)
41 /* Default indexing tree fanout */
42 #define DEFAULT_FANOUT 8
44 /* Default number of data journal heads */
45 #define DEFAULT_JHEADS_CNT 1
47 /* Default positions of different LEBs in the main area */
48 #define DEFAULT_IDX_LEB 0
49 #define DEFAULT_DATA_LEB 1
50 #define DEFAULT_GC_LEB 2
52 /* Default number of LEB numbers in LPT's save table */
53 #define DEFAULT_LSAVE_CNT 256
55 /* Default reserved pool size as a percent of maximum free space */
56 #define DEFAULT_RP_PERCENT 5
58 /* The default maximum size of reserved pool in bytes */
59 #define DEFAULT_MAX_RP_SIZE (5*1024*1024)
61 /* Default time granularity in nanoseconds */
62 #define DEFAULT_TIME_GRAN 1000000000
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;
84 long long tmp64, main_bytes;
87 /* Some functions called from here depend on the @c->key_len filed */
88 c->key_len = UBIFS_SK_LEN;
91 * First of all, we have to calculate default file-system geometry -
92 * log size, journal size, etc.
94 if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT)
95 /* We can first multiply then divide and have no overflow */
96 jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100;
98 jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
100 if (jnl_lebs < UBIFS_MIN_JNL_LEBS)
101 jnl_lebs = UBIFS_MIN_JNL_LEBS;
102 if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL)
103 jnl_lebs = DEFAULT_MAX_JNL / c->leb_size;
106 * The log should be large enough to fit reference nodes for all bud
107 * LEBs. Because buds do not have to start from the beginning of LEBs
108 * (half of the LEB may contain committed data), the log should
109 * generally be larger, make it twice as large.
111 tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1;
112 log_lebs = tmp / c->leb_size;
113 /* Plus one LEB reserved for commit */
115 if (c->leb_cnt - min_leb_cnt > 8) {
116 /* And some extra space to allow writes while committing */
121 max_buds = jnl_lebs - log_lebs;
122 if (max_buds < UBIFS_MIN_BUD_LEBS)
123 max_buds = UBIFS_MIN_BUD_LEBS;
126 * Orphan nodes are stored in a separate area. One node can store a lot
127 * of orphan inode numbers, but when new orphan comes we just add a new
128 * orphan node. At some point the nodes are consolidated into one
131 orph_lebs = UBIFS_MIN_ORPH_LEBS;
132 if (c->leb_cnt - min_leb_cnt > 1)
134 * For debugging purposes it is better to have at least 2
135 * orphan LEBs, because the orphan subsystem would need to do
136 * consolidations and would be stressed more.
140 main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
141 main_lebs -= orph_lebs;
143 lpt_first = UBIFS_LOG_LNUM + log_lebs;
144 c->lsave_cnt = DEFAULT_LSAVE_CNT;
145 c->max_leb_cnt = c->leb_cnt;
146 err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
151 dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
152 lpt_first + lpt_lebs - 1);
154 main_first = c->leb_cnt - main_lebs;
156 /* Create default superblock */
157 tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
158 sup = kzalloc(tmp, GFP_KERNEL);
162 tmp64 = (long long)max_buds * c->leb_size;
164 sup_flags |= UBIFS_FLG_BIGLPT;
166 sup->ch.node_type = UBIFS_SB_NODE;
167 sup->key_hash = UBIFS_KEY_HASH_R5;
168 sup->flags = cpu_to_le32(sup_flags);
169 sup->min_io_size = cpu_to_le32(c->min_io_size);
170 sup->leb_size = cpu_to_le32(c->leb_size);
171 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
172 sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt);
173 sup->max_bud_bytes = cpu_to_le64(tmp64);
174 sup->log_lebs = cpu_to_le32(log_lebs);
175 sup->lpt_lebs = cpu_to_le32(lpt_lebs);
176 sup->orph_lebs = cpu_to_le32(orph_lebs);
177 sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT);
178 sup->fanout = cpu_to_le32(DEFAULT_FANOUT);
179 sup->lsave_cnt = cpu_to_le32(c->lsave_cnt);
180 sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION);
181 sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN);
182 if (c->mount_opts.override_compr)
183 sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
185 sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
187 generate_random_uuid(sup->uuid);
189 main_bytes = (long long)main_lebs * c->leb_size;
190 tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100);
191 if (tmp64 > DEFAULT_MAX_RP_SIZE)
192 tmp64 = DEFAULT_MAX_RP_SIZE;
193 sup->rp_size = cpu_to_le64(tmp64);
194 sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION);
196 err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0);
201 dbg_gen("default superblock created at LEB 0:0");
203 /* Create default master node */
204 mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
208 mst->ch.node_type = UBIFS_MST_NODE;
209 mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM);
210 mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
212 mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
214 tmp = ubifs_idx_node_sz(c, 1);
215 mst->root_len = cpu_to_le32(tmp);
216 mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB);
217 mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
218 mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size));
219 mst->index_size = cpu_to_le64(ALIGN(tmp, 8));
220 mst->lpt_lnum = cpu_to_le32(c->lpt_lnum);
221 mst->lpt_offs = cpu_to_le32(c->lpt_offs);
222 mst->nhead_lnum = cpu_to_le32(c->nhead_lnum);
223 mst->nhead_offs = cpu_to_le32(c->nhead_offs);
224 mst->ltab_lnum = cpu_to_le32(c->ltab_lnum);
225 mst->ltab_offs = cpu_to_le32(c->ltab_offs);
226 mst->lsave_lnum = cpu_to_le32(c->lsave_lnum);
227 mst->lsave_offs = cpu_to_le32(c->lsave_offs);
228 mst->lscan_lnum = cpu_to_le32(main_first);
229 mst->empty_lebs = cpu_to_le32(main_lebs - 2);
230 mst->idx_lebs = cpu_to_le32(1);
231 mst->leb_cnt = cpu_to_le32(c->leb_cnt);
233 /* Calculate lprops statistics */
235 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
236 tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
237 mst->total_free = cpu_to_le64(tmp64);
239 tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
240 ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
243 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
244 mst->total_dirty = cpu_to_le64(tmp64);
246 /* The indexing LEB does not contribute to dark space */
247 tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm);
248 mst->total_dark = cpu_to_le64(tmp64);
250 mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
252 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0);
257 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1,
263 dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
265 /* Create the root indexing node */
266 tmp = ubifs_idx_node_sz(c, 1);
267 idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
271 c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
272 c->key_hash = key_r5_hash;
274 idx->ch.node_type = UBIFS_IDX_NODE;
275 idx->child_cnt = cpu_to_le16(1);
276 ino_key_init(c, &key, UBIFS_ROOT_INO);
277 br = ubifs_idx_branch(c, idx, 0);
278 key_write_idx(c, &key, &br->key);
279 br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
280 br->len = cpu_to_le32(UBIFS_INO_NODE_SZ);
281 err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0);
286 dbg_gen("default root indexing node created LEB %d:0",
287 main_first + DEFAULT_IDX_LEB);
289 /* Create default root inode */
290 tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
291 ino = kzalloc(tmp, GFP_KERNEL);
295 ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
296 ino->ch.node_type = UBIFS_INO_NODE;
297 ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
298 ino->nlink = cpu_to_le32(2);
299 tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec);
300 ino->atime_sec = tmp_le64;
301 ino->ctime_sec = tmp_le64;
302 ino->mtime_sec = tmp_le64;
306 ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
307 ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
309 /* Set compression enabled by default */
310 ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
312 err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
313 main_first + DEFAULT_DATA_LEB, 0);
318 dbg_gen("root inode created at LEB %d:0",
319 main_first + DEFAULT_DATA_LEB);
322 * The first node in the log has to be the commit start node. This is
323 * always the case during normal file-system operation. Write a fake
324 * commit start node to the log.
326 tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size);
327 cs = kzalloc(tmp, GFP_KERNEL);
331 cs->ch.node_type = UBIFS_CS_NODE;
332 err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0);
335 ubifs_msg("default file-system created");
341 * validate_sb - validate superblock node.
342 * @c: UBIFS file-system description object
343 * @sup: superblock node
345 * This function validates superblock node @sup. Since most of data was read
346 * from the superblock and stored in @c, the function validates fields in @c
347 * instead. Returns zero in case of success and %-EINVAL in case of validation
350 static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
353 int err = 1, min_leb_cnt;
360 if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
365 if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
366 ubifs_err("min. I/O unit mismatch: %d in superblock, %d real",
367 le32_to_cpu(sup->min_io_size), c->min_io_size);
371 if (le32_to_cpu(sup->leb_size) != c->leb_size) {
372 ubifs_err("LEB size mismatch: %d in superblock, %d real",
373 le32_to_cpu(sup->leb_size), c->leb_size);
377 if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
378 c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
379 c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
380 c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
386 * Calculate minimum allowed amount of main area LEBs. This is very
387 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
388 * have just read from the superblock.
390 min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
391 min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
393 if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
394 ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, %d minimum required",
395 c->leb_cnt, c->vi.size, min_leb_cnt);
399 if (c->max_leb_cnt < c->leb_cnt) {
400 ubifs_err("max. LEB count %d less than LEB count %d",
401 c->max_leb_cnt, c->leb_cnt);
405 if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
406 ubifs_err("too few main LEBs count %d, must be at least %d",
407 c->main_lebs, UBIFS_MIN_MAIN_LEBS);
411 max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS;
412 if (c->max_bud_bytes < max_bytes) {
413 ubifs_err("too small journal (%lld bytes), must be at least %lld bytes",
414 c->max_bud_bytes, max_bytes);
418 max_bytes = (long long)c->leb_size * c->main_lebs;
419 if (c->max_bud_bytes > max_bytes) {
420 ubifs_err("too large journal size (%lld bytes), only %lld bytes available in the main area",
421 c->max_bud_bytes, max_bytes);
425 if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
426 c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
431 if (c->fanout < UBIFS_MIN_FANOUT ||
432 ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
437 if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
438 c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
439 c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
444 if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
445 c->orph_lebs + c->main_lebs != c->leb_cnt) {
450 if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
455 if (c->rp_size < 0 || max_bytes < c->rp_size) {
460 if (le32_to_cpu(sup->time_gran) > 1000000000 ||
461 le32_to_cpu(sup->time_gran) < 1) {
469 ubifs_err("bad superblock, error %d", err);
470 ubifs_dump_node(c, sup);
475 * ubifs_read_sb_node - read superblock node.
476 * @c: UBIFS file-system description object
478 * This function returns a pointer to the superblock node or a negative error
479 * code. Note, the user of this function is responsible of kfree()'ing the
480 * returned superblock buffer.
482 struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
484 struct ubifs_sb_node *sup;
487 sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
489 return ERR_PTR(-ENOMEM);
491 err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
502 * ubifs_write_sb_node - write superblock node.
503 * @c: UBIFS file-system description object
504 * @sup: superblock node read with 'ubifs_read_sb_node()'
506 * This function returns %0 on success and a negative error code on failure.
508 int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
510 int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
512 ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1);
513 return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len);
517 * ubifs_read_superblock - read superblock.
518 * @c: UBIFS file-system description object
520 * This function finds, reads and checks the superblock. If an empty UBI volume
521 * is being mounted, this function creates default superblock. Returns zero in
522 * case of success, and a negative error code in case of failure.
524 int ubifs_read_superblock(struct ubifs_info *c)
527 struct ubifs_sb_node *sup;
531 err = create_default_filesystem(c);
535 printf("No UBIFS filesystem found!\n");
540 sup = ubifs_read_sb_node(c);
544 c->fmt_version = le32_to_cpu(sup->fmt_version);
545 c->ro_compat_version = le32_to_cpu(sup->ro_compat_version);
548 * The software supports all previous versions but not future versions,
549 * due to the unavailability of time-travelling equipment.
551 if (c->fmt_version > UBIFS_FORMAT_VERSION) {
552 ubifs_assert(!c->ro_media || c->ro_mount);
554 c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) {
555 ubifs_err("on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d",
556 c->fmt_version, c->ro_compat_version,
557 UBIFS_FORMAT_VERSION,
558 UBIFS_RO_COMPAT_VERSION);
559 if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) {
560 ubifs_msg("only R/O mounting is possible");
568 * The FS is mounted R/O, and the media format is
569 * R/O-compatible with the UBIFS implementation, so we can
575 if (c->fmt_version < 3) {
576 ubifs_err("on-flash format version %d is not supported",
582 switch (sup->key_hash) {
583 case UBIFS_KEY_HASH_R5:
584 c->key_hash = key_r5_hash;
585 c->key_hash_type = UBIFS_KEY_HASH_R5;
588 case UBIFS_KEY_HASH_TEST:
589 c->key_hash = key_test_hash;
590 c->key_hash_type = UBIFS_KEY_HASH_TEST;
594 c->key_fmt = sup->key_fmt;
596 switch (c->key_fmt) {
597 case UBIFS_SIMPLE_KEY_FMT:
598 c->key_len = UBIFS_SK_LEN;
601 ubifs_err("unsupported key format");
606 c->leb_cnt = le32_to_cpu(sup->leb_cnt);
607 c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt);
608 c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
609 c->log_lebs = le32_to_cpu(sup->log_lebs);
610 c->lpt_lebs = le32_to_cpu(sup->lpt_lebs);
611 c->orph_lebs = le32_to_cpu(sup->orph_lebs);
612 c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
613 c->fanout = le32_to_cpu(sup->fanout);
614 c->lsave_cnt = le32_to_cpu(sup->lsave_cnt);
615 c->rp_size = le64_to_cpu(sup->rp_size);
617 c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid));
618 c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid));
620 c->rp_uid.val = le32_to_cpu(sup->rp_uid);
621 c->rp_gid.val = le32_to_cpu(sup->rp_gid);
623 sup_flags = le32_to_cpu(sup->flags);
624 if (!c->mount_opts.override_compr)
625 c->default_compr = le16_to_cpu(sup->default_compr);
627 c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
628 memcpy(&c->uuid, &sup->uuid, 16);
629 c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
630 c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP);
632 /* Automatically increase file system size to the maximum size */
633 c->old_leb_cnt = c->leb_cnt;
634 if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
635 c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
637 dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
638 c->old_leb_cnt, c->leb_cnt);
641 dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
642 c->old_leb_cnt, c->leb_cnt);
643 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
644 err = ubifs_write_sb_node(c, sup);
647 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");