blob: 57085e43320fdaf1925fd293f999978e8373077c [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 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.
27 */
28
29#include "ubifs.h"
30#include <linux/random.h>
Artem Bityutskiy4d61db42008-12-18 14:06:51 +020031#include <linux/math64.h>
Artem Bityutskiy1e517642008-07-14 19:08:37 +030032
33/*
34 * Default journal size in logical eraseblocks as a percent of total
35 * flash size.
36 */
37#define DEFAULT_JNL_PERCENT 5
38
39/* Default maximum journal size in bytes */
40#define DEFAULT_MAX_JNL (32*1024*1024)
41
42/* Default indexing tree fanout */
43#define DEFAULT_FANOUT 8
44
45/* Default number of data journal heads */
46#define DEFAULT_JHEADS_CNT 1
47
48/* Default positions of different LEBs in the main area */
49#define DEFAULT_IDX_LEB 0
50#define DEFAULT_DATA_LEB 1
51#define DEFAULT_GC_LEB 2
52
53/* Default number of LEB numbers in LPT's save table */
54#define DEFAULT_LSAVE_CNT 256
55
56/* Default reserved pool size as a percent of maximum free space */
57#define DEFAULT_RP_PERCENT 5
58
59/* The default maximum size of reserved pool in bytes */
60#define DEFAULT_MAX_RP_SIZE (5*1024*1024)
61
62/* Default time granularity in nanoseconds */
63#define DEFAULT_TIME_GRAN 1000000000
64
65/**
66 * create_default_filesystem - format empty UBI volume.
67 * @c: UBIFS file-system description object
68 *
69 * This function creates default empty file-system. Returns zero in case of
70 * success and a negative error code in case of failure.
71 */
72static int create_default_filesystem(struct ubifs_info *c)
73{
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;
80 union ubifs_key key;
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;
Artem Bityutskiy4d61db42008-12-18 14:06:51 +020084 long long tmp64, main_bytes;
Harvey Harrison0ecb9522008-10-24 10:52:57 -070085 __le64 tmp_le64;
Artem Bityutskiy1e517642008-07-14 19:08:37 +030086
87 /* Some functions called from here depend on the @c->key_len filed */
88 c->key_len = UBIFS_SK_LEN;
89
90 /*
91 * First of all, we have to calculate default file-system geometry -
92 * log size, journal size, etc.
93 */
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;
97 else
98 jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT;
99
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;
104
105 /*
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.
110 */
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 */
114 log_lebs += 1;
115 if (c->leb_cnt - min_leb_cnt > 8) {
116 /* And some extra space to allow writes while committing */
117 log_lebs += 1;
118 min_leb_cnt += 1;
119 }
120
121 max_buds = jnl_lebs - log_lebs;
122 if (max_buds < UBIFS_MIN_BUD_LEBS)
123 max_buds = UBIFS_MIN_BUD_LEBS;
124
125 /*
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
129 * orphan node.
130 */
131 orph_lebs = UBIFS_MIN_ORPH_LEBS;
132#ifdef CONFIG_UBIFS_FS_DEBUG
133 if (c->leb_cnt - min_leb_cnt > 1)
134 /*
135 * For debugging purposes it is better to have at least 2
136 * orphan LEBs, because the orphan subsystem would need to do
137 * consolidations and would be stressed more.
138 */
139 orph_lebs += 1;
140#endif
141
142 main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs;
143 main_lebs -= orph_lebs;
144
145 lpt_first = UBIFS_LOG_LNUM + log_lebs;
146 c->lsave_cnt = DEFAULT_LSAVE_CNT;
147 c->max_leb_cnt = c->leb_cnt;
148 err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs,
149 &big_lpt);
150 if (err)
151 return err;
152
153 dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first,
154 lpt_first + lpt_lebs - 1);
155
156 main_first = c->leb_cnt - main_lebs;
157
158 /* Create default superblock */
159 tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
160 sup = kzalloc(tmp, GFP_KERNEL);
161 if (!sup)
162 return -ENOMEM;
163
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200164 tmp64 = (long long)max_buds * c->leb_size;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300165 if (big_lpt)
166 sup_flags |= UBIFS_FLG_BIGLPT;
167
168 sup->ch.node_type = UBIFS_SB_NODE;
169 sup->key_hash = UBIFS_KEY_HASH_R5;
170 sup->flags = cpu_to_le32(sup_flags);
171 sup->min_io_size = cpu_to_le32(c->min_io_size);
172 sup->leb_size = cpu_to_le32(c->leb_size);
173 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
174 sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt);
175 sup->max_bud_bytes = cpu_to_le64(tmp64);
176 sup->log_lebs = cpu_to_le32(log_lebs);
177 sup->lpt_lebs = cpu_to_le32(lpt_lebs);
178 sup->orph_lebs = cpu_to_le32(orph_lebs);
179 sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT);
180 sup->fanout = cpu_to_le32(DEFAULT_FANOUT);
181 sup->lsave_cnt = cpu_to_le32(c->lsave_cnt);
182 sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300183 sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN);
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200184 if (c->mount_opts.override_compr)
185 sup->default_compr = cpu_to_le16(c->mount_opts.compr_type);
186 else
187 sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300188
189 generate_random_uuid(sup->uuid);
190
Artem Bityutskiy4d61db42008-12-18 14:06:51 +0200191 main_bytes = (long long)main_lebs * c->leb_size;
192 tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300193 if (tmp64 > DEFAULT_MAX_RP_SIZE)
194 tmp64 = DEFAULT_MAX_RP_SIZE;
195 sup->rp_size = cpu_to_le64(tmp64);
Artem Bityutskiy963f0cf2009-03-26 12:51:21 +0200196 sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300197
198 err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0, UBI_LONGTERM);
199 kfree(sup);
200 if (err)
201 return err;
202
203 dbg_gen("default superblock created at LEB 0:0");
204
205 /* Create default master node */
206 mst = kzalloc(c->mst_node_alsz, GFP_KERNEL);
207 if (!mst)
208 return -ENOMEM;
209
210 mst->ch.node_type = UBIFS_MST_NODE;
211 mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM);
212 mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO);
213 mst->cmt_no = 0;
214 mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
215 mst->root_offs = 0;
216 tmp = ubifs_idx_node_sz(c, 1);
217 mst->root_len = cpu_to_le32(tmp);
218 mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB);
219 mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB);
220 mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size));
221 mst->index_size = cpu_to_le64(ALIGN(tmp, 8));
222 mst->lpt_lnum = cpu_to_le32(c->lpt_lnum);
223 mst->lpt_offs = cpu_to_le32(c->lpt_offs);
224 mst->nhead_lnum = cpu_to_le32(c->nhead_lnum);
225 mst->nhead_offs = cpu_to_le32(c->nhead_offs);
226 mst->ltab_lnum = cpu_to_le32(c->ltab_lnum);
227 mst->ltab_offs = cpu_to_le32(c->ltab_offs);
228 mst->lsave_lnum = cpu_to_le32(c->lsave_lnum);
229 mst->lsave_offs = cpu_to_le32(c->lsave_offs);
230 mst->lscan_lnum = cpu_to_le32(main_first);
231 mst->empty_lebs = cpu_to_le32(main_lebs - 2);
232 mst->idx_lebs = cpu_to_le32(1);
233 mst->leb_cnt = cpu_to_le32(c->leb_cnt);
234
235 /* Calculate lprops statistics */
236 tmp64 = main_bytes;
237 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
238 tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
239 mst->total_free = cpu_to_le64(tmp64);
240
241 tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size);
242 ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) -
243 UBIFS_INO_NODE_SZ;
244 tmp64 += ino_waste;
245 tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8);
246 mst->total_dirty = cpu_to_le64(tmp64);
247
248 /* The indexing LEB does not contribute to dark space */
249 tmp64 = (c->main_lebs - 1) * c->dark_wm;
250 mst->total_dark = cpu_to_le64(tmp64);
251
252 mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ);
253
254 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0,
255 UBI_UNKNOWN);
256 if (err) {
257 kfree(mst);
258 return err;
259 }
260 err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, 0,
261 UBI_UNKNOWN);
262 kfree(mst);
263 if (err)
264 return err;
265
266 dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM);
267
268 /* Create the root indexing node */
269 tmp = ubifs_idx_node_sz(c, 1);
270 idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL);
271 if (!idx)
272 return -ENOMEM;
273
274 c->key_fmt = UBIFS_SIMPLE_KEY_FMT;
275 c->key_hash = key_r5_hash;
276
277 idx->ch.node_type = UBIFS_IDX_NODE;
278 idx->child_cnt = cpu_to_le16(1);
279 ino_key_init(c, &key, UBIFS_ROOT_INO);
280 br = ubifs_idx_branch(c, idx, 0);
281 key_write_idx(c, &key, &br->key);
282 br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB);
283 br->len = cpu_to_le32(UBIFS_INO_NODE_SZ);
284 err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0,
285 UBI_UNKNOWN);
286 kfree(idx);
287 if (err)
288 return err;
289
290 dbg_gen("default root indexing node created LEB %d:0",
291 main_first + DEFAULT_IDX_LEB);
292
293 /* Create default root inode */
294 tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size);
295 ino = kzalloc(tmp, GFP_KERNEL);
296 if (!ino)
297 return -ENOMEM;
298
299 ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO);
300 ino->ch.node_type = UBIFS_INO_NODE;
301 ino->creat_sqnum = cpu_to_le64(++c->max_sqnum);
302 ino->nlink = cpu_to_le32(2);
Harvey Harrison0ecb9522008-10-24 10:52:57 -0700303 tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec);
304 ino->atime_sec = tmp_le64;
305 ino->ctime_sec = tmp_le64;
306 ino->mtime_sec = tmp_le64;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300307 ino->atime_nsec = 0;
308 ino->ctime_nsec = 0;
309 ino->mtime_nsec = 0;
310 ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO);
311 ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ);
312
313 /* Set compression enabled by default */
314 ino->flags = cpu_to_le32(UBIFS_COMPR_FL);
315
316 err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ,
317 main_first + DEFAULT_DATA_LEB, 0,
318 UBI_UNKNOWN);
319 kfree(ino);
320 if (err)
321 return err;
322
323 dbg_gen("root inode created at LEB %d:0",
324 main_first + DEFAULT_DATA_LEB);
325
326 /*
327 * The first node in the log has to be the commit start node. This is
328 * always the case during normal file-system operation. Write a fake
329 * commit start node to the log.
330 */
331 tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size);
332 cs = kzalloc(tmp, GFP_KERNEL);
333 if (!cs)
334 return -ENOMEM;
335
336 cs->ch.node_type = UBIFS_CS_NODE;
337 err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM,
338 0, UBI_UNKNOWN);
339 kfree(cs);
340
341 ubifs_msg("default file-system created");
342 return 0;
343}
344
345/**
346 * validate_sb - validate superblock node.
347 * @c: UBIFS file-system description object
348 * @sup: superblock node
349 *
350 * This function validates superblock node @sup. Since most of data was read
351 * from the superblock and stored in @c, the function validates fields in @c
352 * instead. Returns zero in case of success and %-EINVAL in case of validation
353 * failure.
354 */
355static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup)
356{
357 long long max_bytes;
358 int err = 1, min_leb_cnt;
359
360 if (!c->key_hash) {
361 err = 2;
362 goto failed;
363 }
364
365 if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) {
366 err = 3;
367 goto failed;
368 }
369
370 if (le32_to_cpu(sup->min_io_size) != c->min_io_size) {
371 ubifs_err("min. I/O unit mismatch: %d in superblock, %d real",
372 le32_to_cpu(sup->min_io_size), c->min_io_size);
373 goto failed;
374 }
375
376 if (le32_to_cpu(sup->leb_size) != c->leb_size) {
377 ubifs_err("LEB size mismatch: %d in superblock, %d real",
378 le32_to_cpu(sup->leb_size), c->leb_size);
379 goto failed;
380 }
381
382 if (c->log_lebs < UBIFS_MIN_LOG_LEBS ||
383 c->lpt_lebs < UBIFS_MIN_LPT_LEBS ||
384 c->orph_lebs < UBIFS_MIN_ORPH_LEBS ||
385 c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
386 err = 4;
387 goto failed;
388 }
389
390 /*
391 * Calculate minimum allowed amount of main area LEBs. This is very
392 * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we
393 * have just read from the superblock.
394 */
395 min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs;
396 min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6;
397
398 if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) {
399 ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, "
400 "%d minimum required", c->leb_cnt, c->vi.size,
401 min_leb_cnt);
402 goto failed;
403 }
404
405 if (c->max_leb_cnt < c->leb_cnt) {
406 ubifs_err("max. LEB count %d less than LEB count %d",
407 c->max_leb_cnt, c->leb_cnt);
408 goto failed;
409 }
410
411 if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) {
412 err = 7;
413 goto failed;
414 }
415
416 if (c->max_bud_bytes < (long long)c->leb_size * UBIFS_MIN_BUD_LEBS ||
417 c->max_bud_bytes > (long long)c->leb_size * c->main_lebs) {
418 err = 8;
419 goto failed;
420 }
421
422 if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 ||
423 c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) {
424 err = 9;
425 goto failed;
426 }
427
428 if (c->fanout < UBIFS_MIN_FANOUT ||
429 ubifs_idx_node_sz(c, c->fanout) > c->leb_size) {
430 err = 10;
431 goto failed;
432 }
433
434 if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT &&
435 c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS -
436 c->log_lebs - c->lpt_lebs - c->orph_lebs)) {
437 err = 11;
438 goto failed;
439 }
440
441 if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs +
442 c->orph_lebs + c->main_lebs != c->leb_cnt) {
443 err = 12;
444 goto failed;
445 }
446
447 if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) {
448 err = 13;
449 goto failed;
450 }
451
452 max_bytes = c->main_lebs * (long long)c->leb_size;
453 if (c->rp_size < 0 || max_bytes < c->rp_size) {
454 err = 14;
455 goto failed;
456 }
457
458 if (le32_to_cpu(sup->time_gran) > 1000000000 ||
459 le32_to_cpu(sup->time_gran) < 1) {
460 err = 15;
461 goto failed;
462 }
463
464 return 0;
465
466failed:
467 ubifs_err("bad superblock, error %d", err);
468 dbg_dump_node(c, sup);
469 return -EINVAL;
470}
471
472/**
473 * ubifs_read_sb_node - read superblock node.
474 * @c: UBIFS file-system description object
475 *
476 * This function returns a pointer to the superblock node or a negative error
477 * code.
478 */
479struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c)
480{
481 struct ubifs_sb_node *sup;
482 int err;
483
484 sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS);
485 if (!sup)
486 return ERR_PTR(-ENOMEM);
487
488 err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ,
489 UBIFS_SB_LNUM, 0);
490 if (err) {
491 kfree(sup);
492 return ERR_PTR(err);
493 }
494
495 return sup;
496}
497
498/**
499 * ubifs_write_sb_node - write superblock node.
500 * @c: UBIFS file-system description object
501 * @sup: superblock node read with 'ubifs_read_sb_node()'
502 *
503 * This function returns %0 on success and a negative error code on failure.
504 */
505int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup)
506{
507 int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size);
508
509 ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1);
510 return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len, UBI_LONGTERM);
511}
512
513/**
514 * ubifs_read_superblock - read superblock.
515 * @c: UBIFS file-system description object
516 *
517 * This function finds, reads and checks the superblock. If an empty UBI volume
518 * is being mounted, this function creates default superblock. Returns zero in
519 * case of success, and a negative error code in case of failure.
520 */
521int ubifs_read_superblock(struct ubifs_info *c)
522{
523 int err, sup_flags;
524 struct ubifs_sb_node *sup;
525
526 if (c->empty) {
527 err = create_default_filesystem(c);
528 if (err)
529 return err;
530 }
531
532 sup = ubifs_read_sb_node(c);
533 if (IS_ERR(sup))
534 return PTR_ERR(sup);
535
Artem Bityutskiy963f0cf2009-03-26 12:51:21 +0200536 c->fmt_version = le32_to_cpu(sup->fmt_version);
537 c->ro_compat_version = le32_to_cpu(sup->ro_compat_version);
538
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300539 /*
540 * The software supports all previous versions but not future versions,
541 * due to the unavailability of time-travelling equipment.
542 */
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300543 if (c->fmt_version > UBIFS_FORMAT_VERSION) {
Artem Bityutskiy963f0cf2009-03-26 12:51:21 +0200544 struct super_block *sb = c->vfs_sb;
545 int mounting_ro = sb->s_flags & MS_RDONLY;
546
547 ubifs_assert(!c->ro_media || mounting_ro);
548 if (!mounting_ro ||
549 c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) {
550 ubifs_err("on-flash format version is w%d/r%d, but "
551 "software only supports up to version "
552 "w%d/r%d", c->fmt_version,
553 c->ro_compat_version, UBIFS_FORMAT_VERSION,
554 UBIFS_RO_COMPAT_VERSION);
555 if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) {
556 ubifs_msg("only R/O mounting is possible");
557 err = -EROFS;
558 } else
559 err = -EINVAL;
560 goto out;
561 }
562
563 /*
564 * The FS is mounted R/O, and the media format is
565 * R/O-compatible with the UBIFS implementation, so we can
566 * mount.
567 */
568 c->rw_incompat = 1;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300569 }
570
571 if (c->fmt_version < 3) {
572 ubifs_err("on-flash format version %d is not supported",
573 c->fmt_version);
574 err = -EINVAL;
575 goto out;
576 }
577
578 switch (sup->key_hash) {
579 case UBIFS_KEY_HASH_R5:
580 c->key_hash = key_r5_hash;
581 c->key_hash_type = UBIFS_KEY_HASH_R5;
582 break;
583
584 case UBIFS_KEY_HASH_TEST:
585 c->key_hash = key_test_hash;
586 c->key_hash_type = UBIFS_KEY_HASH_TEST;
587 break;
588 };
589
590 c->key_fmt = sup->key_fmt;
591
592 switch (c->key_fmt) {
593 case UBIFS_SIMPLE_KEY_FMT:
594 c->key_len = UBIFS_SK_LEN;
595 break;
596 default:
597 ubifs_err("unsupported key format");
598 err = -EINVAL;
599 goto out;
600 }
601
602 c->leb_cnt = le32_to_cpu(sup->leb_cnt);
603 c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt);
604 c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes);
605 c->log_lebs = le32_to_cpu(sup->log_lebs);
606 c->lpt_lebs = le32_to_cpu(sup->lpt_lebs);
607 c->orph_lebs = le32_to_cpu(sup->orph_lebs);
608 c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT;
609 c->fanout = le32_to_cpu(sup->fanout);
610 c->lsave_cnt = le32_to_cpu(sup->lsave_cnt);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300611 c->rp_size = le64_to_cpu(sup->rp_size);
612 c->rp_uid = le32_to_cpu(sup->rp_uid);
613 c->rp_gid = le32_to_cpu(sup->rp_gid);
614 sup_flags = le32_to_cpu(sup->flags);
Artem Bityutskiy553dea42008-11-01 14:57:49 +0200615 if (!c->mount_opts.override_compr)
616 c->default_compr = le16_to_cpu(sup->default_compr);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300617
618 c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300619 memcpy(&c->uuid, &sup->uuid, 16);
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300620 c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT);
621
622 /* Automatically increase file system size to the maximum size */
623 c->old_leb_cnt = c->leb_cnt;
624 if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) {
625 c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size);
626 if (c->vfs_sb->s_flags & MS_RDONLY)
627 dbg_mnt("Auto resizing (ro) from %d LEBs to %d LEBs",
628 c->old_leb_cnt, c->leb_cnt);
629 else {
630 dbg_mnt("Auto resizing (sb) from %d LEBs to %d LEBs",
631 c->old_leb_cnt, c->leb_cnt);
632 sup->leb_cnt = cpu_to_le32(c->leb_cnt);
633 err = ubifs_write_sb_node(c, sup);
634 if (err)
635 goto out;
636 c->old_leb_cnt = c->leb_cnt;
637 }
638 }
639
640 c->log_bytes = (long long)c->log_lebs * c->leb_size;
641 c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1;
642 c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs;
643 c->lpt_last = c->lpt_first + c->lpt_lebs - 1;
644 c->orph_first = c->lpt_last + 1;
645 c->orph_last = c->orph_first + c->orph_lebs - 1;
646 c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS;
647 c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs;
648 c->main_first = c->leb_cnt - c->main_lebs;
Artem Bityutskiy1e517642008-07-14 19:08:37 +0300649
650 err = validate_sb(c, sup);
651out:
652 kfree(sup);
653 return err;
654}