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1e51764a AB |
1 | /* |
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" | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
1e51764a | 31 | #include <linux/random.h> |
4d61db4f | 32 | #include <linux/math64.h> |
1e51764a AB |
33 | |
34 | /* | |
35 | * Default journal size in logical eraseblocks as a percent of total | |
36 | * flash size. | |
37 | */ | |
38 | #define DEFAULT_JNL_PERCENT 5 | |
39 | ||
40 | /* Default maximum journal size in bytes */ | |
41 | #define DEFAULT_MAX_JNL (32*1024*1024) | |
42 | ||
43 | /* Default indexing tree fanout */ | |
44 | #define DEFAULT_FANOUT 8 | |
45 | ||
46 | /* Default number of data journal heads */ | |
47 | #define DEFAULT_JHEADS_CNT 1 | |
48 | ||
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 | |
53 | ||
54 | /* Default number of LEB numbers in LPT's save table */ | |
55 | #define DEFAULT_LSAVE_CNT 256 | |
56 | ||
57 | /* Default reserved pool size as a percent of maximum free space */ | |
58 | #define DEFAULT_RP_PERCENT 5 | |
59 | ||
60 | /* The default maximum size of reserved pool in bytes */ | |
61 | #define DEFAULT_MAX_RP_SIZE (5*1024*1024) | |
62 | ||
63 | /* Default time granularity in nanoseconds */ | |
64 | #define DEFAULT_TIME_GRAN 1000000000 | |
65 | ||
66 | /** | |
67 | * create_default_filesystem - format empty UBI volume. | |
68 | * @c: UBIFS file-system description object | |
69 | * | |
70 | * This function creates default empty file-system. Returns zero in case of | |
71 | * success and a negative error code in case of failure. | |
72 | */ | |
73 | static int create_default_filesystem(struct ubifs_info *c) | |
74 | { | |
75 | struct ubifs_sb_node *sup; | |
76 | struct ubifs_mst_node *mst; | |
77 | struct ubifs_idx_node *idx; | |
78 | struct ubifs_branch *br; | |
79 | struct ubifs_ino_node *ino; | |
80 | struct ubifs_cs_node *cs; | |
81 | union ubifs_key key; | |
82 | int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first; | |
83 | int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0; | |
84 | int min_leb_cnt = UBIFS_MIN_LEB_CNT; | |
4d61db4f | 85 | long long tmp64, main_bytes; |
0ecb9529 | 86 | __le64 tmp_le64; |
1e51764a AB |
87 | |
88 | /* Some functions called from here depend on the @c->key_len filed */ | |
89 | c->key_len = UBIFS_SK_LEN; | |
90 | ||
91 | /* | |
92 | * First of all, we have to calculate default file-system geometry - | |
93 | * log size, journal size, etc. | |
94 | */ | |
95 | if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT) | |
96 | /* We can first multiply then divide and have no overflow */ | |
97 | jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100; | |
98 | else | |
99 | jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT; | |
100 | ||
101 | if (jnl_lebs < UBIFS_MIN_JNL_LEBS) | |
102 | jnl_lebs = UBIFS_MIN_JNL_LEBS; | |
103 | if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL) | |
104 | jnl_lebs = DEFAULT_MAX_JNL / c->leb_size; | |
105 | ||
106 | /* | |
107 | * The log should be large enough to fit reference nodes for all bud | |
108 | * LEBs. Because buds do not have to start from the beginning of LEBs | |
109 | * (half of the LEB may contain committed data), the log should | |
110 | * generally be larger, make it twice as large. | |
111 | */ | |
112 | tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1; | |
113 | log_lebs = tmp / c->leb_size; | |
114 | /* Plus one LEB reserved for commit */ | |
115 | log_lebs += 1; | |
116 | if (c->leb_cnt - min_leb_cnt > 8) { | |
117 | /* And some extra space to allow writes while committing */ | |
118 | log_lebs += 1; | |
119 | min_leb_cnt += 1; | |
120 | } | |
121 | ||
122 | max_buds = jnl_lebs - log_lebs; | |
123 | if (max_buds < UBIFS_MIN_BUD_LEBS) | |
124 | max_buds = UBIFS_MIN_BUD_LEBS; | |
125 | ||
126 | /* | |
127 | * Orphan nodes are stored in a separate area. One node can store a lot | |
128 | * of orphan inode numbers, but when new orphan comes we just add a new | |
129 | * orphan node. At some point the nodes are consolidated into one | |
130 | * orphan node. | |
131 | */ | |
132 | orph_lebs = UBIFS_MIN_ORPH_LEBS; | |
133 | #ifdef CONFIG_UBIFS_FS_DEBUG | |
134 | if (c->leb_cnt - min_leb_cnt > 1) | |
135 | /* | |
136 | * For debugging purposes it is better to have at least 2 | |
137 | * orphan LEBs, because the orphan subsystem would need to do | |
138 | * consolidations and would be stressed more. | |
139 | */ | |
140 | orph_lebs += 1; | |
141 | #endif | |
142 | ||
143 | main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs; | |
144 | main_lebs -= orph_lebs; | |
145 | ||
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, | |
150 | &big_lpt); | |
151 | if (err) | |
152 | return err; | |
153 | ||
154 | dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first, | |
155 | lpt_first + lpt_lebs - 1); | |
156 | ||
157 | main_first = c->leb_cnt - main_lebs; | |
158 | ||
159 | /* Create default superblock */ | |
160 | tmp = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); | |
161 | sup = kzalloc(tmp, GFP_KERNEL); | |
162 | if (!sup) | |
163 | return -ENOMEM; | |
164 | ||
4d61db4f | 165 | tmp64 = (long long)max_buds * c->leb_size; |
1e51764a AB |
166 | if (big_lpt) |
167 | sup_flags |= UBIFS_FLG_BIGLPT; | |
168 | ||
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); | |
1e51764a | 184 | sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN); |
553dea4d AB |
185 | if (c->mount_opts.override_compr) |
186 | sup->default_compr = cpu_to_le16(c->mount_opts.compr_type); | |
187 | else | |
188 | sup->default_compr = cpu_to_le16(UBIFS_COMPR_LZO); | |
1e51764a AB |
189 | |
190 | generate_random_uuid(sup->uuid); | |
191 | ||
4d61db4f AB |
192 | main_bytes = (long long)main_lebs * c->leb_size; |
193 | tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100); | |
1e51764a AB |
194 | if (tmp64 > DEFAULT_MAX_RP_SIZE) |
195 | tmp64 = DEFAULT_MAX_RP_SIZE; | |
196 | sup->rp_size = cpu_to_le64(tmp64); | |
963f0cf6 | 197 | sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION); |
1e51764a AB |
198 | |
199 | err = ubifs_write_node(c, sup, UBIFS_SB_NODE_SZ, 0, 0, UBI_LONGTERM); | |
200 | kfree(sup); | |
201 | if (err) | |
202 | return err; | |
203 | ||
204 | dbg_gen("default superblock created at LEB 0:0"); | |
205 | ||
206 | /* Create default master node */ | |
207 | mst = kzalloc(c->mst_node_alsz, GFP_KERNEL); | |
208 | if (!mst) | |
209 | return -ENOMEM; | |
210 | ||
211 | mst->ch.node_type = UBIFS_MST_NODE; | |
212 | mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM); | |
213 | mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO); | |
214 | mst->cmt_no = 0; | |
215 | mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); | |
216 | mst->root_offs = 0; | |
217 | tmp = ubifs_idx_node_sz(c, 1); | |
218 | mst->root_len = cpu_to_le32(tmp); | |
219 | mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB); | |
220 | mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); | |
221 | mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size)); | |
222 | mst->index_size = cpu_to_le64(ALIGN(tmp, 8)); | |
223 | mst->lpt_lnum = cpu_to_le32(c->lpt_lnum); | |
224 | mst->lpt_offs = cpu_to_le32(c->lpt_offs); | |
225 | mst->nhead_lnum = cpu_to_le32(c->nhead_lnum); | |
226 | mst->nhead_offs = cpu_to_le32(c->nhead_offs); | |
227 | mst->ltab_lnum = cpu_to_le32(c->ltab_lnum); | |
228 | mst->ltab_offs = cpu_to_le32(c->ltab_offs); | |
229 | mst->lsave_lnum = cpu_to_le32(c->lsave_lnum); | |
230 | mst->lsave_offs = cpu_to_le32(c->lsave_offs); | |
231 | mst->lscan_lnum = cpu_to_le32(main_first); | |
232 | mst->empty_lebs = cpu_to_le32(main_lebs - 2); | |
233 | mst->idx_lebs = cpu_to_le32(1); | |
234 | mst->leb_cnt = cpu_to_le32(c->leb_cnt); | |
235 | ||
236 | /* Calculate lprops statistics */ | |
237 | tmp64 = main_bytes; | |
238 | tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); | |
239 | tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); | |
240 | mst->total_free = cpu_to_le64(tmp64); | |
241 | ||
242 | tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); | |
243 | ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) - | |
244 | UBIFS_INO_NODE_SZ; | |
245 | tmp64 += ino_waste; | |
246 | tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8); | |
247 | mst->total_dirty = cpu_to_le64(tmp64); | |
248 | ||
249 | /* The indexing LEB does not contribute to dark space */ | |
7606f85a | 250 | tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm); |
1e51764a AB |
251 | mst->total_dark = cpu_to_le64(tmp64); |
252 | ||
253 | mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ); | |
254 | ||
255 | err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0, | |
256 | UBI_UNKNOWN); | |
257 | if (err) { | |
258 | kfree(mst); | |
259 | return err; | |
260 | } | |
261 | err = ubifs_write_node(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, 0, | |
262 | UBI_UNKNOWN); | |
263 | kfree(mst); | |
264 | if (err) | |
265 | return err; | |
266 | ||
267 | dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM); | |
268 | ||
269 | /* Create the root indexing node */ | |
270 | tmp = ubifs_idx_node_sz(c, 1); | |
271 | idx = kzalloc(ALIGN(tmp, c->min_io_size), GFP_KERNEL); | |
272 | if (!idx) | |
273 | return -ENOMEM; | |
274 | ||
275 | c->key_fmt = UBIFS_SIMPLE_KEY_FMT; | |
276 | c->key_hash = key_r5_hash; | |
277 | ||
278 | idx->ch.node_type = UBIFS_IDX_NODE; | |
279 | idx->child_cnt = cpu_to_le16(1); | |
280 | ino_key_init(c, &key, UBIFS_ROOT_INO); | |
281 | br = ubifs_idx_branch(c, idx, 0); | |
282 | key_write_idx(c, &key, &br->key); | |
283 | br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB); | |
284 | br->len = cpu_to_le32(UBIFS_INO_NODE_SZ); | |
285 | err = ubifs_write_node(c, idx, tmp, main_first + DEFAULT_IDX_LEB, 0, | |
286 | UBI_UNKNOWN); | |
287 | kfree(idx); | |
288 | if (err) | |
289 | return err; | |
290 | ||
291 | dbg_gen("default root indexing node created LEB %d:0", | |
292 | main_first + DEFAULT_IDX_LEB); | |
293 | ||
294 | /* Create default root inode */ | |
295 | tmp = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); | |
296 | ino = kzalloc(tmp, GFP_KERNEL); | |
297 | if (!ino) | |
298 | return -ENOMEM; | |
299 | ||
300 | ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO); | |
301 | ino->ch.node_type = UBIFS_INO_NODE; | |
302 | ino->creat_sqnum = cpu_to_le64(++c->max_sqnum); | |
303 | ino->nlink = cpu_to_le32(2); | |
0ecb9529 HH |
304 | tmp_le64 = cpu_to_le64(CURRENT_TIME_SEC.tv_sec); |
305 | ino->atime_sec = tmp_le64; | |
306 | ino->ctime_sec = tmp_le64; | |
307 | ino->mtime_sec = tmp_le64; | |
1e51764a AB |
308 | ino->atime_nsec = 0; |
309 | ino->ctime_nsec = 0; | |
310 | ino->mtime_nsec = 0; | |
311 | ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO); | |
312 | ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ); | |
313 | ||
314 | /* Set compression enabled by default */ | |
315 | ino->flags = cpu_to_le32(UBIFS_COMPR_FL); | |
316 | ||
317 | err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ, | |
318 | main_first + DEFAULT_DATA_LEB, 0, | |
319 | UBI_UNKNOWN); | |
320 | kfree(ino); | |
321 | if (err) | |
322 | return err; | |
323 | ||
324 | dbg_gen("root inode created at LEB %d:0", | |
325 | main_first + DEFAULT_DATA_LEB); | |
326 | ||
327 | /* | |
328 | * The first node in the log has to be the commit start node. This is | |
329 | * always the case during normal file-system operation. Write a fake | |
330 | * commit start node to the log. | |
331 | */ | |
332 | tmp = ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size); | |
333 | cs = kzalloc(tmp, GFP_KERNEL); | |
334 | if (!cs) | |
335 | return -ENOMEM; | |
336 | ||
337 | cs->ch.node_type = UBIFS_CS_NODE; | |
338 | err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, | |
339 | 0, UBI_UNKNOWN); | |
340 | kfree(cs); | |
341 | ||
342 | ubifs_msg("default file-system created"); | |
343 | return 0; | |
344 | } | |
345 | ||
346 | /** | |
347 | * validate_sb - validate superblock node. | |
348 | * @c: UBIFS file-system description object | |
349 | * @sup: superblock node | |
350 | * | |
351 | * This function validates superblock node @sup. Since most of data was read | |
352 | * from the superblock and stored in @c, the function validates fields in @c | |
353 | * instead. Returns zero in case of success and %-EINVAL in case of validation | |
354 | * failure. | |
355 | */ | |
356 | static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) | |
357 | { | |
358 | long long max_bytes; | |
359 | int err = 1, min_leb_cnt; | |
360 | ||
361 | if (!c->key_hash) { | |
362 | err = 2; | |
363 | goto failed; | |
364 | } | |
365 | ||
366 | if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { | |
367 | err = 3; | |
368 | goto failed; | |
369 | } | |
370 | ||
371 | if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { | |
372 | ubifs_err("min. I/O unit mismatch: %d in superblock, %d real", | |
373 | le32_to_cpu(sup->min_io_size), c->min_io_size); | |
374 | goto failed; | |
375 | } | |
376 | ||
377 | if (le32_to_cpu(sup->leb_size) != c->leb_size) { | |
378 | ubifs_err("LEB size mismatch: %d in superblock, %d real", | |
379 | le32_to_cpu(sup->leb_size), c->leb_size); | |
380 | goto failed; | |
381 | } | |
382 | ||
383 | if (c->log_lebs < UBIFS_MIN_LOG_LEBS || | |
384 | c->lpt_lebs < UBIFS_MIN_LPT_LEBS || | |
385 | c->orph_lebs < UBIFS_MIN_ORPH_LEBS || | |
386 | c->main_lebs < UBIFS_MIN_MAIN_LEBS) { | |
387 | err = 4; | |
388 | goto failed; | |
389 | } | |
390 | ||
391 | /* | |
392 | * Calculate minimum allowed amount of main area LEBs. This is very | |
393 | * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we | |
394 | * have just read from the superblock. | |
395 | */ | |
396 | min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; | |
397 | min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; | |
398 | ||
399 | if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) { | |
400 | ubifs_err("bad LEB count: %d in superblock, %d on UBI volume, " | |
401 | "%d minimum required", c->leb_cnt, c->vi.size, | |
402 | min_leb_cnt); | |
403 | goto failed; | |
404 | } | |
405 | ||
406 | if (c->max_leb_cnt < c->leb_cnt) { | |
407 | ubifs_err("max. LEB count %d less than LEB count %d", | |
408 | c->max_leb_cnt, c->leb_cnt); | |
409 | goto failed; | |
410 | } | |
411 | ||
412 | if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { | |
413 | err = 7; | |
414 | goto failed; | |
415 | } | |
416 | ||
417 | if (c->max_bud_bytes < (long long)c->leb_size * UBIFS_MIN_BUD_LEBS || | |
418 | c->max_bud_bytes > (long long)c->leb_size * c->main_lebs) { | |
419 | err = 8; | |
420 | goto failed; | |
421 | } | |
422 | ||
423 | if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || | |
424 | c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { | |
425 | err = 9; | |
426 | goto failed; | |
427 | } | |
428 | ||
429 | if (c->fanout < UBIFS_MIN_FANOUT || | |
430 | ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { | |
431 | err = 10; | |
432 | goto failed; | |
433 | } | |
434 | ||
435 | if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && | |
436 | c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - | |
437 | c->log_lebs - c->lpt_lebs - c->orph_lebs)) { | |
438 | err = 11; | |
439 | goto failed; | |
440 | } | |
441 | ||
442 | if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + | |
443 | c->orph_lebs + c->main_lebs != c->leb_cnt) { | |
444 | err = 12; | |
445 | goto failed; | |
446 | } | |
447 | ||
448 | if (c->default_compr < 0 || c->default_compr >= UBIFS_COMPR_TYPES_CNT) { | |
449 | err = 13; | |
450 | goto failed; | |
451 | } | |
452 | ||
453 | max_bytes = c->main_lebs * (long long)c->leb_size; | |
454 | if (c->rp_size < 0 || max_bytes < c->rp_size) { | |
455 | err = 14; | |
456 | goto failed; | |
457 | } | |
458 | ||
459 | if (le32_to_cpu(sup->time_gran) > 1000000000 || | |
460 | le32_to_cpu(sup->time_gran) < 1) { | |
461 | err = 15; | |
462 | goto failed; | |
463 | } | |
464 | ||
465 | return 0; | |
466 | ||
467 | failed: | |
468 | ubifs_err("bad superblock, error %d", err); | |
469 | dbg_dump_node(c, sup); | |
470 | return -EINVAL; | |
471 | } | |
472 | ||
473 | /** | |
474 | * ubifs_read_sb_node - read superblock node. | |
475 | * @c: UBIFS file-system description object | |
476 | * | |
477 | * This function returns a pointer to the superblock node or a negative error | |
eaeee242 AB |
478 | * code. Note, the user of this function is responsible of kfree()'ing the |
479 | * returned superblock buffer. | |
1e51764a AB |
480 | */ |
481 | struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) | |
482 | { | |
483 | struct ubifs_sb_node *sup; | |
484 | int err; | |
485 | ||
486 | sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); | |
487 | if (!sup) | |
488 | return ERR_PTR(-ENOMEM); | |
489 | ||
490 | err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, | |
491 | UBIFS_SB_LNUM, 0); | |
492 | if (err) { | |
493 | kfree(sup); | |
494 | return ERR_PTR(err); | |
495 | } | |
496 | ||
497 | return sup; | |
498 | } | |
499 | ||
500 | /** | |
501 | * ubifs_write_sb_node - write superblock node. | |
502 | * @c: UBIFS file-system description object | |
503 | * @sup: superblock node read with 'ubifs_read_sb_node()' | |
504 | * | |
505 | * This function returns %0 on success and a negative error code on failure. | |
506 | */ | |
507 | int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup) | |
508 | { | |
509 | int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); | |
510 | ||
511 | ubifs_prepare_node(c, sup, UBIFS_SB_NODE_SZ, 1); | |
512 | return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len, UBI_LONGTERM); | |
513 | } | |
514 | ||
515 | /** | |
516 | * ubifs_read_superblock - read superblock. | |
517 | * @c: UBIFS file-system description object | |
518 | * | |
519 | * This function finds, reads and checks the superblock. If an empty UBI volume | |
520 | * is being mounted, this function creates default superblock. Returns zero in | |
521 | * case of success, and a negative error code in case of failure. | |
522 | */ | |
523 | int ubifs_read_superblock(struct ubifs_info *c) | |
524 | { | |
525 | int err, sup_flags; | |
526 | struct ubifs_sb_node *sup; | |
527 | ||
528 | if (c->empty) { | |
529 | err = create_default_filesystem(c); | |
530 | if (err) | |
531 | return err; | |
532 | } | |
533 | ||
534 | sup = ubifs_read_sb_node(c); | |
535 | if (IS_ERR(sup)) | |
536 | return PTR_ERR(sup); | |
537 | ||
963f0cf6 AB |
538 | c->fmt_version = le32_to_cpu(sup->fmt_version); |
539 | c->ro_compat_version = le32_to_cpu(sup->ro_compat_version); | |
540 | ||
1e51764a AB |
541 | /* |
542 | * The software supports all previous versions but not future versions, | |
543 | * due to the unavailability of time-travelling equipment. | |
544 | */ | |
1e51764a | 545 | if (c->fmt_version > UBIFS_FORMAT_VERSION) { |
2ef13294 AB |
546 | ubifs_assert(!c->ro_media || c->ro_mount); |
547 | if (!c->ro_mount || | |
963f0cf6 AB |
548 | c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) { |
549 | ubifs_err("on-flash format version is w%d/r%d, but " | |
550 | "software only supports up to version " | |
551 | "w%d/r%d", c->fmt_version, | |
552 | c->ro_compat_version, UBIFS_FORMAT_VERSION, | |
553 | UBIFS_RO_COMPAT_VERSION); | |
554 | if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) { | |
555 | ubifs_msg("only R/O mounting is possible"); | |
556 | err = -EROFS; | |
557 | } else | |
558 | err = -EINVAL; | |
559 | goto out; | |
560 | } | |
561 | ||
562 | /* | |
563 | * The FS is mounted R/O, and the media format is | |
564 | * R/O-compatible with the UBIFS implementation, so we can | |
565 | * mount. | |
566 | */ | |
567 | c->rw_incompat = 1; | |
1e51764a AB |
568 | } |
569 | ||
570 | if (c->fmt_version < 3) { | |
571 | ubifs_err("on-flash format version %d is not supported", | |
572 | c->fmt_version); | |
573 | err = -EINVAL; | |
574 | goto out; | |
575 | } | |
576 | ||
577 | switch (sup->key_hash) { | |
578 | case UBIFS_KEY_HASH_R5: | |
579 | c->key_hash = key_r5_hash; | |
580 | c->key_hash_type = UBIFS_KEY_HASH_R5; | |
581 | break; | |
582 | ||
583 | case UBIFS_KEY_HASH_TEST: | |
584 | c->key_hash = key_test_hash; | |
585 | c->key_hash_type = UBIFS_KEY_HASH_TEST; | |
586 | break; | |
587 | }; | |
588 | ||
589 | c->key_fmt = sup->key_fmt; | |
590 | ||
591 | switch (c->key_fmt) { | |
592 | case UBIFS_SIMPLE_KEY_FMT: | |
593 | c->key_len = UBIFS_SK_LEN; | |
594 | break; | |
595 | default: | |
596 | ubifs_err("unsupported key format"); | |
597 | err = -EINVAL; | |
598 | goto out; | |
599 | } | |
600 | ||
601 | c->leb_cnt = le32_to_cpu(sup->leb_cnt); | |
602 | c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); | |
603 | c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); | |
604 | c->log_lebs = le32_to_cpu(sup->log_lebs); | |
605 | c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); | |
606 | c->orph_lebs = le32_to_cpu(sup->orph_lebs); | |
607 | c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; | |
608 | c->fanout = le32_to_cpu(sup->fanout); | |
609 | c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); | |
1e51764a AB |
610 | c->rp_size = le64_to_cpu(sup->rp_size); |
611 | c->rp_uid = le32_to_cpu(sup->rp_uid); | |
612 | c->rp_gid = le32_to_cpu(sup->rp_gid); | |
613 | sup_flags = le32_to_cpu(sup->flags); | |
553dea4d AB |
614 | if (!c->mount_opts.override_compr) |
615 | c->default_compr = le16_to_cpu(sup->default_compr); | |
1e51764a AB |
616 | |
617 | c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran); | |
1e51764a | 618 | memcpy(&c->uuid, &sup->uuid, 16); |
1e51764a | 619 | c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); |
9f58d350 | 620 | c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); |
1e51764a AB |
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); | |
2ef13294 | 626 | if (c->ro_mount) |
1e51764a AB |
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; | |
1e51764a AB |
649 | |
650 | err = validate_sb(c, sup); | |
651 | out: | |
652 | kfree(sup); | |
653 | return err; | |
654 | } | |
6554a657 MC |
655 | |
656 | /** | |
657 | * fixup_leb - fixup/unmap an LEB containing free space. | |
658 | * @c: UBIFS file-system description object | |
659 | * @lnum: the LEB number to fix up | |
660 | * @len: number of used bytes in LEB (starting at offset 0) | |
661 | * | |
662 | * This function reads the contents of the given LEB number @lnum, then fixes | |
663 | * it up, so that empty min. I/O units in the end of LEB are actually erased on | |
664 | * flash (rather than being just all-0xff real data). If the LEB is completely | |
665 | * empty, it is simply unmapped. | |
666 | */ | |
667 | static int fixup_leb(struct ubifs_info *c, int lnum, int len) | |
668 | { | |
669 | int err; | |
670 | ||
671 | ubifs_assert(len >= 0); | |
672 | ubifs_assert(len % c->min_io_size == 0); | |
673 | ubifs_assert(len < c->leb_size); | |
674 | ||
675 | if (len == 0) { | |
676 | dbg_mnt("unmap empty LEB %d", lnum); | |
d3b2578f | 677 | return ubifs_leb_unmap(c, lnum); |
6554a657 MC |
678 | } |
679 | ||
680 | dbg_mnt("fixup LEB %d, data len %d", lnum, len); | |
d304820a | 681 | err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1); |
6554a657 MC |
682 | if (err) |
683 | return err; | |
684 | ||
d3b2578f | 685 | return ubifs_leb_change(c, lnum, c->sbuf, len, UBI_UNKNOWN); |
6554a657 MC |
686 | } |
687 | ||
688 | /** | |
689 | * fixup_free_space - find & remap all LEBs containing free space. | |
690 | * @c: UBIFS file-system description object | |
691 | * | |
692 | * This function walks through all LEBs in the filesystem and fiexes up those | |
693 | * containing free/empty space. | |
694 | */ | |
695 | static int fixup_free_space(struct ubifs_info *c) | |
696 | { | |
697 | int lnum, err = 0; | |
698 | struct ubifs_lprops *lprops; | |
699 | ||
700 | ubifs_get_lprops(c); | |
701 | ||
702 | /* Fixup LEBs in the master area */ | |
703 | for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) { | |
704 | err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz); | |
705 | if (err) | |
706 | goto out; | |
707 | } | |
708 | ||
709 | /* Unmap unused log LEBs */ | |
710 | lnum = ubifs_next_log_lnum(c, c->lhead_lnum); | |
711 | while (lnum != c->ltail_lnum) { | |
712 | err = fixup_leb(c, lnum, 0); | |
713 | if (err) | |
714 | goto out; | |
715 | lnum = ubifs_next_log_lnum(c, lnum); | |
716 | } | |
717 | ||
718 | /* Fixup the current log head */ | |
719 | err = fixup_leb(c, c->lhead_lnum, c->lhead_offs); | |
720 | if (err) | |
721 | goto out; | |
722 | ||
723 | /* Fixup LEBs in the LPT area */ | |
724 | for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { | |
725 | int free = c->ltab[lnum - c->lpt_first].free; | |
726 | ||
727 | if (free > 0) { | |
728 | err = fixup_leb(c, lnum, c->leb_size - free); | |
729 | if (err) | |
730 | goto out; | |
731 | } | |
732 | } | |
733 | ||
734 | /* Unmap LEBs in the orphans area */ | |
735 | for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { | |
736 | err = fixup_leb(c, lnum, 0); | |
737 | if (err) | |
738 | goto out; | |
739 | } | |
740 | ||
741 | /* Fixup LEBs in the main area */ | |
742 | for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { | |
743 | lprops = ubifs_lpt_lookup(c, lnum); | |
744 | if (IS_ERR(lprops)) { | |
745 | err = PTR_ERR(lprops); | |
746 | goto out; | |
747 | } | |
748 | ||
749 | if (lprops->free > 0) { | |
750 | err = fixup_leb(c, lnum, c->leb_size - lprops->free); | |
751 | if (err) | |
752 | goto out; | |
753 | } | |
754 | } | |
755 | ||
756 | out: | |
757 | ubifs_release_lprops(c); | |
758 | return err; | |
759 | } | |
760 | ||
761 | /** | |
762 | * ubifs_fixup_free_space - find & fix all LEBs with free space. | |
763 | * @c: UBIFS file-system description object | |
764 | * | |
765 | * This function fixes up LEBs containing free space on first mount, if the | |
766 | * appropriate flag was set when the FS was created. Each LEB with one or more | |
767 | * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure | |
768 | * the free space is actually erased. E.g., this is necessary for some NAND | |
769 | * chips, since the free space may have been programmed like real "0xff" data | |
770 | * (generating a non-0xff ECC), causing future writes to the not-really-erased | |
771 | * NAND pages to behave badly. After the space is fixed up, the superblock flag | |
772 | * is cleared, so that this is skipped for all future mounts. | |
773 | */ | |
774 | int ubifs_fixup_free_space(struct ubifs_info *c) | |
775 | { | |
776 | int err; | |
777 | struct ubifs_sb_node *sup; | |
778 | ||
779 | ubifs_assert(c->space_fixup); | |
780 | ubifs_assert(!c->ro_mount); | |
781 | ||
782 | ubifs_msg("start fixing up free space"); | |
783 | ||
784 | err = fixup_free_space(c); | |
785 | if (err) | |
786 | return err; | |
787 | ||
788 | sup = ubifs_read_sb_node(c); | |
789 | if (IS_ERR(sup)) | |
790 | return PTR_ERR(sup); | |
791 | ||
792 | /* Free-space fixup is no longer required */ | |
793 | c->space_fixup = 0; | |
794 | sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP); | |
795 | ||
796 | err = ubifs_write_sb_node(c, sup); | |
797 | kfree(sup); | |
798 | if (err) | |
799 | return err; | |
800 | ||
801 | ubifs_msg("free space fixup complete"); | |
802 | return err; | |
803 | } |