1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * This file is part of UBIFS.
4 *
5 * Copyright (C) 2006-2008 Nokia Corporation.
6 *
7 * Authors: Adrian Hunter
8 * Artem Bityutskiy (Битюцкий Артём)
9 */
10
11 /*
12 * This file implements the LEB properties tree (LPT) area. The LPT area
13 * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and
14 * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits
15 * between the log and the orphan area.
16 *
17 * The LPT area is like a miniature self-contained file system. It is required
18 * that it never runs out of space, is fast to access and update, and scales
19 * logarithmically. The LEB properties tree is implemented as a wandering tree
20 * much like the TNC, and the LPT area has its own garbage collection.
21 *
22 * The LPT has two slightly different forms called the "small model" and the
23 * "big model". The small model is used when the entire LEB properties table
24 * can be written into a single eraseblock. In that case, garbage collection
25 * consists of just writing the whole table, which therefore makes all other
26 * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
27 * selected for garbage collection, which consists of marking the clean nodes in
28 * that LEB as dirty, and then only the dirty nodes are written out. Also, in
29 * the case of the big model, a table of LEB numbers is saved so that the entire
30 * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
31 * mounted.
32 */
33
34 #include "ubifs.h"
35 #ifndef __UBOOT__
36 #include <linux/crc16.h>
37 #include <linux/math64.h>
38 #include <linux/slab.h>
39 #else
40 #include <linux/compat.h>
41 #include <linux/err.h>
42 #include <ubi_uboot.h>
43 #include "crc16.h"
44 #endif
45
46 /**
47 * do_calc_lpt_geom - calculate sizes for the LPT area.
48 * @c: the UBIFS file-system description object
49 *
50 * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
51 * properties of the flash and whether LPT is "big" (c->big_lpt).
52 */
do_calc_lpt_geom(struct ubifs_info * c)53 static void do_calc_lpt_geom(struct ubifs_info *c)
54 {
55 int i, n, bits, per_leb_wastage, max_pnode_cnt;
56 long long sz, tot_wastage;
57
58 n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
59 max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
60
61 c->lpt_hght = 1;
62 n = UBIFS_LPT_FANOUT;
63 while (n < max_pnode_cnt) {
64 c->lpt_hght += 1;
65 n <<= UBIFS_LPT_FANOUT_SHIFT;
66 }
67
68 c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
69
70 n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
71 c->nnode_cnt = n;
72 for (i = 1; i < c->lpt_hght; i++) {
73 n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
74 c->nnode_cnt += n;
75 }
76
77 c->space_bits = fls(c->leb_size) - 3;
78 c->lpt_lnum_bits = fls(c->lpt_lebs);
79 c->lpt_offs_bits = fls(c->leb_size - 1);
80 c->lpt_spc_bits = fls(c->leb_size);
81
82 n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
83 c->pcnt_bits = fls(n - 1);
84
85 c->lnum_bits = fls(c->max_leb_cnt - 1);
86
87 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
88 (c->big_lpt ? c->pcnt_bits : 0) +
89 (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
90 c->pnode_sz = (bits + 7) / 8;
91
92 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
93 (c->big_lpt ? c->pcnt_bits : 0) +
94 (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
95 c->nnode_sz = (bits + 7) / 8;
96
97 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
98 c->lpt_lebs * c->lpt_spc_bits * 2;
99 c->ltab_sz = (bits + 7) / 8;
100
101 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
102 c->lnum_bits * c->lsave_cnt;
103 c->lsave_sz = (bits + 7) / 8;
104
105 /* Calculate the minimum LPT size */
106 c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
107 c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
108 c->lpt_sz += c->ltab_sz;
109 if (c->big_lpt)
110 c->lpt_sz += c->lsave_sz;
111
112 /* Add wastage */
113 sz = c->lpt_sz;
114 per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
115 sz += per_leb_wastage;
116 tot_wastage = per_leb_wastage;
117 while (sz > c->leb_size) {
118 sz += per_leb_wastage;
119 sz -= c->leb_size;
120 tot_wastage += per_leb_wastage;
121 }
122 tot_wastage += ALIGN(sz, c->min_io_size) - sz;
123 c->lpt_sz += tot_wastage;
124 }
125
126 /**
127 * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area.
128 * @c: the UBIFS file-system description object
129 *
130 * This function returns %0 on success and a negative error code on failure.
131 */
ubifs_calc_lpt_geom(struct ubifs_info * c)132 int ubifs_calc_lpt_geom(struct ubifs_info *c)
133 {
134 int lebs_needed;
135 long long sz;
136
137 do_calc_lpt_geom(c);
138
139 /* Verify that lpt_lebs is big enough */
140 sz = c->lpt_sz * 2; /* Must have at least 2 times the size */
141 lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size);
142 if (lebs_needed > c->lpt_lebs) {
143 ubifs_err(c, "too few LPT LEBs");
144 return -EINVAL;
145 }
146
147 /* Verify that ltab fits in a single LEB (since ltab is a single node */
148 if (c->ltab_sz > c->leb_size) {
149 ubifs_err(c, "LPT ltab too big");
150 return -EINVAL;
151 }
152
153 c->check_lpt_free = c->big_lpt;
154 return 0;
155 }
156
157 /**
158 * calc_dflt_lpt_geom - calculate default LPT geometry.
159 * @c: the UBIFS file-system description object
160 * @main_lebs: number of main area LEBs is passed and returned here
161 * @big_lpt: whether the LPT area is "big" is returned here
162 *
163 * The size of the LPT area depends on parameters that themselves are dependent
164 * on the size of the LPT area. This function, successively recalculates the LPT
165 * area geometry until the parameters and resultant geometry are consistent.
166 *
167 * This function returns %0 on success and a negative error code on failure.
168 */
calc_dflt_lpt_geom(struct ubifs_info * c,int * main_lebs,int * big_lpt)169 static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs,
170 int *big_lpt)
171 {
172 int i, lebs_needed;
173 long long sz;
174
175 /* Start by assuming the minimum number of LPT LEBs */
176 c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
177 c->main_lebs = *main_lebs - c->lpt_lebs;
178 if (c->main_lebs <= 0)
179 return -EINVAL;
180
181 /* And assume we will use the small LPT model */
182 c->big_lpt = 0;
183
184 /*
185 * Calculate the geometry based on assumptions above and then see if it
186 * makes sense
187 */
188 do_calc_lpt_geom(c);
189
190 /* Small LPT model must have lpt_sz < leb_size */
191 if (c->lpt_sz > c->leb_size) {
192 /* Nope, so try again using big LPT model */
193 c->big_lpt = 1;
194 do_calc_lpt_geom(c);
195 }
196
197 /* Now check there are enough LPT LEBs */
198 for (i = 0; i < 64 ; i++) {
199 sz = c->lpt_sz * 4; /* Allow 4 times the size */
200 lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size);
201 if (lebs_needed > c->lpt_lebs) {
202 /* Not enough LPT LEBs so try again with more */
203 c->lpt_lebs = lebs_needed;
204 c->main_lebs = *main_lebs - c->lpt_lebs;
205 if (c->main_lebs <= 0)
206 return -EINVAL;
207 do_calc_lpt_geom(c);
208 continue;
209 }
210 if (c->ltab_sz > c->leb_size) {
211 ubifs_err(c, "LPT ltab too big");
212 return -EINVAL;
213 }
214 *main_lebs = c->main_lebs;
215 *big_lpt = c->big_lpt;
216 return 0;
217 }
218 return -EINVAL;
219 }
220
221 /**
222 * pack_bits - pack bit fields end-to-end.
223 * @addr: address at which to pack (passed and next address returned)
224 * @pos: bit position at which to pack (passed and next position returned)
225 * @val: value to pack
226 * @nrbits: number of bits of value to pack (1-32)
227 */
pack_bits(uint8_t ** addr,int * pos,uint32_t val,int nrbits)228 static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
229 {
230 uint8_t *p = *addr;
231 int b = *pos;
232
233 ubifs_assert(nrbits > 0);
234 ubifs_assert(nrbits <= 32);
235 ubifs_assert(*pos >= 0);
236 ubifs_assert(*pos < 8);
237 ubifs_assert((val >> nrbits) == 0 || nrbits == 32);
238 if (b) {
239 *p |= ((uint8_t)val) << b;
240 nrbits += b;
241 if (nrbits > 8) {
242 *++p = (uint8_t)(val >>= (8 - b));
243 if (nrbits > 16) {
244 *++p = (uint8_t)(val >>= 8);
245 if (nrbits > 24) {
246 *++p = (uint8_t)(val >>= 8);
247 if (nrbits > 32)
248 *++p = (uint8_t)(val >>= 8);
249 }
250 }
251 }
252 } else {
253 *p = (uint8_t)val;
254 if (nrbits > 8) {
255 *++p = (uint8_t)(val >>= 8);
256 if (nrbits > 16) {
257 *++p = (uint8_t)(val >>= 8);
258 if (nrbits > 24)
259 *++p = (uint8_t)(val >>= 8);
260 }
261 }
262 }
263 b = nrbits & 7;
264 if (b == 0)
265 p++;
266 *addr = p;
267 *pos = b;
268 }
269
270 /**
271 * ubifs_unpack_bits - unpack bit fields.
272 * @addr: address at which to unpack (passed and next address returned)
273 * @pos: bit position at which to unpack (passed and next position returned)
274 * @nrbits: number of bits of value to unpack (1-32)
275 *
276 * This functions returns the value unpacked.
277 */
ubifs_unpack_bits(uint8_t ** addr,int * pos,int nrbits)278 uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
279 {
280 const int k = 32 - nrbits;
281 uint8_t *p = *addr;
282 int b = *pos;
283 uint32_t uninitialized_var(val);
284 const int bytes = (nrbits + b + 7) >> 3;
285
286 ubifs_assert(nrbits > 0);
287 ubifs_assert(nrbits <= 32);
288 ubifs_assert(*pos >= 0);
289 ubifs_assert(*pos < 8);
290 if (b) {
291 switch (bytes) {
292 case 2:
293 val = p[1];
294 break;
295 case 3:
296 val = p[1] | ((uint32_t)p[2] << 8);
297 break;
298 case 4:
299 val = p[1] | ((uint32_t)p[2] << 8) |
300 ((uint32_t)p[3] << 16);
301 break;
302 case 5:
303 val = p[1] | ((uint32_t)p[2] << 8) |
304 ((uint32_t)p[3] << 16) |
305 ((uint32_t)p[4] << 24);
306 }
307 val <<= (8 - b);
308 val |= *p >> b;
309 nrbits += b;
310 } else {
311 switch (bytes) {
312 case 1:
313 val = p[0];
314 break;
315 case 2:
316 val = p[0] | ((uint32_t)p[1] << 8);
317 break;
318 case 3:
319 val = p[0] | ((uint32_t)p[1] << 8) |
320 ((uint32_t)p[2] << 16);
321 break;
322 case 4:
323 val = p[0] | ((uint32_t)p[1] << 8) |
324 ((uint32_t)p[2] << 16) |
325 ((uint32_t)p[3] << 24);
326 break;
327 }
328 }
329 val <<= k;
330 val >>= k;
331 b = nrbits & 7;
332 p += nrbits >> 3;
333 *addr = p;
334 *pos = b;
335 ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
336 return val;
337 }
338
339 /**
340 * ubifs_pack_pnode - pack all the bit fields of a pnode.
341 * @c: UBIFS file-system description object
342 * @buf: buffer into which to pack
343 * @pnode: pnode to pack
344 */
ubifs_pack_pnode(struct ubifs_info * c,void * buf,struct ubifs_pnode * pnode)345 void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
346 struct ubifs_pnode *pnode)
347 {
348 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
349 int i, pos = 0;
350 uint16_t crc;
351
352 pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
353 if (c->big_lpt)
354 pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
355 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
356 pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
357 c->space_bits);
358 pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
359 c->space_bits);
360 if (pnode->lprops[i].flags & LPROPS_INDEX)
361 pack_bits(&addr, &pos, 1, 1);
362 else
363 pack_bits(&addr, &pos, 0, 1);
364 }
365 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
366 c->pnode_sz - UBIFS_LPT_CRC_BYTES);
367 addr = buf;
368 pos = 0;
369 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
370 }
371
372 /**
373 * ubifs_pack_nnode - pack all the bit fields of a nnode.
374 * @c: UBIFS file-system description object
375 * @buf: buffer into which to pack
376 * @nnode: nnode to pack
377 */
ubifs_pack_nnode(struct ubifs_info * c,void * buf,struct ubifs_nnode * nnode)378 void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
379 struct ubifs_nnode *nnode)
380 {
381 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
382 int i, pos = 0;
383 uint16_t crc;
384
385 pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
386 if (c->big_lpt)
387 pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
388 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
389 int lnum = nnode->nbranch[i].lnum;
390
391 if (lnum == 0)
392 lnum = c->lpt_last + 1;
393 pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
394 pack_bits(&addr, &pos, nnode->nbranch[i].offs,
395 c->lpt_offs_bits);
396 }
397 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
398 c->nnode_sz - UBIFS_LPT_CRC_BYTES);
399 addr = buf;
400 pos = 0;
401 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
402 }
403
404 /**
405 * ubifs_pack_ltab - pack the LPT's own lprops table.
406 * @c: UBIFS file-system description object
407 * @buf: buffer into which to pack
408 * @ltab: LPT's own lprops table to pack
409 */
ubifs_pack_ltab(struct ubifs_info * c,void * buf,struct ubifs_lpt_lprops * ltab)410 void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
411 struct ubifs_lpt_lprops *ltab)
412 {
413 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
414 int i, pos = 0;
415 uint16_t crc;
416
417 pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
418 for (i = 0; i < c->lpt_lebs; i++) {
419 pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
420 pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
421 }
422 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
423 c->ltab_sz - UBIFS_LPT_CRC_BYTES);
424 addr = buf;
425 pos = 0;
426 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
427 }
428
429 /**
430 * ubifs_pack_lsave - pack the LPT's save table.
431 * @c: UBIFS file-system description object
432 * @buf: buffer into which to pack
433 * @lsave: LPT's save table to pack
434 */
ubifs_pack_lsave(struct ubifs_info * c,void * buf,int * lsave)435 void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
436 {
437 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
438 int i, pos = 0;
439 uint16_t crc;
440
441 pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS);
442 for (i = 0; i < c->lsave_cnt; i++)
443 pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
444 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
445 c->lsave_sz - UBIFS_LPT_CRC_BYTES);
446 addr = buf;
447 pos = 0;
448 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
449 }
450
451 /**
452 * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
453 * @c: UBIFS file-system description object
454 * @lnum: LEB number to which to add dirty space
455 * @dirty: amount of dirty space to add
456 */
ubifs_add_lpt_dirt(struct ubifs_info * c,int lnum,int dirty)457 void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
458 {
459 if (!dirty || !lnum)
460 return;
461 dbg_lp("LEB %d add %d to %d",
462 lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
463 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
464 c->ltab[lnum - c->lpt_first].dirty += dirty;
465 }
466
467 /**
468 * set_ltab - set LPT LEB properties.
469 * @c: UBIFS file-system description object
470 * @lnum: LEB number
471 * @free: amount of free space
472 * @dirty: amount of dirty space
473 */
set_ltab(struct ubifs_info * c,int lnum,int free,int dirty)474 static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
475 {
476 dbg_lp("LEB %d free %d dirty %d to %d %d",
477 lnum, c->ltab[lnum - c->lpt_first].free,
478 c->ltab[lnum - c->lpt_first].dirty, free, dirty);
479 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
480 c->ltab[lnum - c->lpt_first].free = free;
481 c->ltab[lnum - c->lpt_first].dirty = dirty;
482 }
483
484 /**
485 * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
486 * @c: UBIFS file-system description object
487 * @nnode: nnode for which to add dirt
488 */
ubifs_add_nnode_dirt(struct ubifs_info * c,struct ubifs_nnode * nnode)489 void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
490 {
491 struct ubifs_nnode *np = nnode->parent;
492
493 if (np)
494 ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
495 c->nnode_sz);
496 else {
497 ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
498 if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
499 c->lpt_drty_flgs |= LTAB_DIRTY;
500 ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
501 }
502 }
503 }
504
505 /**
506 * add_pnode_dirt - add dirty space to LPT LEB properties.
507 * @c: UBIFS file-system description object
508 * @pnode: pnode for which to add dirt
509 */
add_pnode_dirt(struct ubifs_info * c,struct ubifs_pnode * pnode)510 static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
511 {
512 ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
513 c->pnode_sz);
514 }
515
516 /**
517 * calc_nnode_num - calculate nnode number.
518 * @row: the row in the tree (root is zero)
519 * @col: the column in the row (leftmost is zero)
520 *
521 * The nnode number is a number that uniquely identifies a nnode and can be used
522 * easily to traverse the tree from the root to that nnode.
523 *
524 * This function calculates and returns the nnode number for the nnode at @row
525 * and @col.
526 */
calc_nnode_num(int row,int col)527 static int calc_nnode_num(int row, int col)
528 {
529 int num, bits;
530
531 num = 1;
532 while (row--) {
533 bits = (col & (UBIFS_LPT_FANOUT - 1));
534 col >>= UBIFS_LPT_FANOUT_SHIFT;
535 num <<= UBIFS_LPT_FANOUT_SHIFT;
536 num |= bits;
537 }
538 return num;
539 }
540
541 /**
542 * calc_nnode_num_from_parent - calculate nnode number.
543 * @c: UBIFS file-system description object
544 * @parent: parent nnode
545 * @iip: index in parent
546 *
547 * The nnode number is a number that uniquely identifies a nnode and can be used
548 * easily to traverse the tree from the root to that nnode.
549 *
550 * This function calculates and returns the nnode number based on the parent's
551 * nnode number and the index in parent.
552 */
calc_nnode_num_from_parent(const struct ubifs_info * c,struct ubifs_nnode * parent,int iip)553 static int calc_nnode_num_from_parent(const struct ubifs_info *c,
554 struct ubifs_nnode *parent, int iip)
555 {
556 int num, shft;
557
558 if (!parent)
559 return 1;
560 shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
561 num = parent->num ^ (1 << shft);
562 num |= (UBIFS_LPT_FANOUT + iip) << shft;
563 return num;
564 }
565
566 /**
567 * calc_pnode_num_from_parent - calculate pnode number.
568 * @c: UBIFS file-system description object
569 * @parent: parent nnode
570 * @iip: index in parent
571 *
572 * The pnode number is a number that uniquely identifies a pnode and can be used
573 * easily to traverse the tree from the root to that pnode.
574 *
575 * This function calculates and returns the pnode number based on the parent's
576 * nnode number and the index in parent.
577 */
calc_pnode_num_from_parent(const struct ubifs_info * c,struct ubifs_nnode * parent,int iip)578 static int calc_pnode_num_from_parent(const struct ubifs_info *c,
579 struct ubifs_nnode *parent, int iip)
580 {
581 int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
582
583 for (i = 0; i < n; i++) {
584 num <<= UBIFS_LPT_FANOUT_SHIFT;
585 num |= pnum & (UBIFS_LPT_FANOUT - 1);
586 pnum >>= UBIFS_LPT_FANOUT_SHIFT;
587 }
588 num <<= UBIFS_LPT_FANOUT_SHIFT;
589 num |= iip;
590 return num;
591 }
592
593 /**
594 * ubifs_create_dflt_lpt - create default LPT.
595 * @c: UBIFS file-system description object
596 * @main_lebs: number of main area LEBs is passed and returned here
597 * @lpt_first: LEB number of first LPT LEB
598 * @lpt_lebs: number of LEBs for LPT is passed and returned here
599 * @big_lpt: use big LPT model is passed and returned here
600 *
601 * This function returns %0 on success and a negative error code on failure.
602 */
ubifs_create_dflt_lpt(struct ubifs_info * c,int * main_lebs,int lpt_first,int * lpt_lebs,int * big_lpt)603 int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
604 int *lpt_lebs, int *big_lpt)
605 {
606 int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row;
607 int blnum, boffs, bsz, bcnt;
608 struct ubifs_pnode *pnode = NULL;
609 struct ubifs_nnode *nnode = NULL;
610 void *buf = NULL, *p;
611 struct ubifs_lpt_lprops *ltab = NULL;
612 int *lsave = NULL;
613
614 err = calc_dflt_lpt_geom(c, main_lebs, big_lpt);
615 if (err)
616 return err;
617 *lpt_lebs = c->lpt_lebs;
618
619 /* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */
620 c->lpt_first = lpt_first;
621 /* Needed by 'set_ltab()' */
622 c->lpt_last = lpt_first + c->lpt_lebs - 1;
623 /* Needed by 'ubifs_pack_lsave()' */
624 c->main_first = c->leb_cnt - *main_lebs;
625
626 lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
627 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
628 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
629 buf = vmalloc(c->leb_size);
630 ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
631 if (!pnode || !nnode || !buf || !ltab || !lsave) {
632 err = -ENOMEM;
633 goto out;
634 }
635
636 ubifs_assert(!c->ltab);
637 c->ltab = ltab; /* Needed by set_ltab */
638
639 /* Initialize LPT's own lprops */
640 for (i = 0; i < c->lpt_lebs; i++) {
641 ltab[i].free = c->leb_size;
642 ltab[i].dirty = 0;
643 ltab[i].tgc = 0;
644 ltab[i].cmt = 0;
645 }
646
647 lnum = lpt_first;
648 p = buf;
649 /* Number of leaf nodes (pnodes) */
650 cnt = c->pnode_cnt;
651
652 /*
653 * The first pnode contains the LEB properties for the LEBs that contain
654 * the root inode node and the root index node of the index tree.
655 */
656 node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8);
657 iopos = ALIGN(node_sz, c->min_io_size);
658 pnode->lprops[0].free = c->leb_size - iopos;
659 pnode->lprops[0].dirty = iopos - node_sz;
660 pnode->lprops[0].flags = LPROPS_INDEX;
661
662 node_sz = UBIFS_INO_NODE_SZ;
663 iopos = ALIGN(node_sz, c->min_io_size);
664 pnode->lprops[1].free = c->leb_size - iopos;
665 pnode->lprops[1].dirty = iopos - node_sz;
666
667 for (i = 2; i < UBIFS_LPT_FANOUT; i++)
668 pnode->lprops[i].free = c->leb_size;
669
670 /* Add first pnode */
671 ubifs_pack_pnode(c, p, pnode);
672 p += c->pnode_sz;
673 len = c->pnode_sz;
674 pnode->num += 1;
675
676 /* Reset pnode values for remaining pnodes */
677 pnode->lprops[0].free = c->leb_size;
678 pnode->lprops[0].dirty = 0;
679 pnode->lprops[0].flags = 0;
680
681 pnode->lprops[1].free = c->leb_size;
682 pnode->lprops[1].dirty = 0;
683
684 /*
685 * To calculate the internal node branches, we keep information about
686 * the level below.
687 */
688 blnum = lnum; /* LEB number of level below */
689 boffs = 0; /* Offset of level below */
690 bcnt = cnt; /* Number of nodes in level below */
691 bsz = c->pnode_sz; /* Size of nodes in level below */
692
693 /* Add all remaining pnodes */
694 for (i = 1; i < cnt; i++) {
695 if (len + c->pnode_sz > c->leb_size) {
696 alen = ALIGN(len, c->min_io_size);
697 set_ltab(c, lnum, c->leb_size - alen, alen - len);
698 memset(p, 0xff, alen - len);
699 err = ubifs_leb_change(c, lnum++, buf, alen);
700 if (err)
701 goto out;
702 p = buf;
703 len = 0;
704 }
705 ubifs_pack_pnode(c, p, pnode);
706 p += c->pnode_sz;
707 len += c->pnode_sz;
708 /*
709 * pnodes are simply numbered left to right starting at zero,
710 * which means the pnode number can be used easily to traverse
711 * down the tree to the corresponding pnode.
712 */
713 pnode->num += 1;
714 }
715
716 row = 0;
717 for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT)
718 row += 1;
719 /* Add all nnodes, one level at a time */
720 while (1) {
721 /* Number of internal nodes (nnodes) at next level */
722 cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT);
723 for (i = 0; i < cnt; i++) {
724 if (len + c->nnode_sz > c->leb_size) {
725 alen = ALIGN(len, c->min_io_size);
726 set_ltab(c, lnum, c->leb_size - alen,
727 alen - len);
728 memset(p, 0xff, alen - len);
729 err = ubifs_leb_change(c, lnum++, buf, alen);
730 if (err)
731 goto out;
732 p = buf;
733 len = 0;
734 }
735 /* Only 1 nnode at this level, so it is the root */
736 if (cnt == 1) {
737 c->lpt_lnum = lnum;
738 c->lpt_offs = len;
739 }
740 /* Set branches to the level below */
741 for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
742 if (bcnt) {
743 if (boffs + bsz > c->leb_size) {
744 blnum += 1;
745 boffs = 0;
746 }
747 nnode->nbranch[j].lnum = blnum;
748 nnode->nbranch[j].offs = boffs;
749 boffs += bsz;
750 bcnt--;
751 } else {
752 nnode->nbranch[j].lnum = 0;
753 nnode->nbranch[j].offs = 0;
754 }
755 }
756 nnode->num = calc_nnode_num(row, i);
757 ubifs_pack_nnode(c, p, nnode);
758 p += c->nnode_sz;
759 len += c->nnode_sz;
760 }
761 /* Only 1 nnode at this level, so it is the root */
762 if (cnt == 1)
763 break;
764 /* Update the information about the level below */
765 bcnt = cnt;
766 bsz = c->nnode_sz;
767 row -= 1;
768 }
769
770 if (*big_lpt) {
771 /* Need to add LPT's save table */
772 if (len + c->lsave_sz > c->leb_size) {
773 alen = ALIGN(len, c->min_io_size);
774 set_ltab(c, lnum, c->leb_size - alen, alen - len);
775 memset(p, 0xff, alen - len);
776 err = ubifs_leb_change(c, lnum++, buf, alen);
777 if (err)
778 goto out;
779 p = buf;
780 len = 0;
781 }
782
783 c->lsave_lnum = lnum;
784 c->lsave_offs = len;
785
786 for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++)
787 lsave[i] = c->main_first + i;
788 for (; i < c->lsave_cnt; i++)
789 lsave[i] = c->main_first;
790
791 ubifs_pack_lsave(c, p, lsave);
792 p += c->lsave_sz;
793 len += c->lsave_sz;
794 }
795
796 /* Need to add LPT's own LEB properties table */
797 if (len + c->ltab_sz > c->leb_size) {
798 alen = ALIGN(len, c->min_io_size);
799 set_ltab(c, lnum, c->leb_size - alen, alen - len);
800 memset(p, 0xff, alen - len);
801 err = ubifs_leb_change(c, lnum++, buf, alen);
802 if (err)
803 goto out;
804 p = buf;
805 len = 0;
806 }
807
808 c->ltab_lnum = lnum;
809 c->ltab_offs = len;
810
811 /* Update ltab before packing it */
812 len += c->ltab_sz;
813 alen = ALIGN(len, c->min_io_size);
814 set_ltab(c, lnum, c->leb_size - alen, alen - len);
815
816 ubifs_pack_ltab(c, p, ltab);
817 p += c->ltab_sz;
818
819 /* Write remaining buffer */
820 memset(p, 0xff, alen - len);
821 err = ubifs_leb_change(c, lnum, buf, alen);
822 if (err)
823 goto out;
824
825 c->nhead_lnum = lnum;
826 c->nhead_offs = ALIGN(len, c->min_io_size);
827
828 dbg_lp("space_bits %d", c->space_bits);
829 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
830 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
831 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
832 dbg_lp("pcnt_bits %d", c->pcnt_bits);
833 dbg_lp("lnum_bits %d", c->lnum_bits);
834 dbg_lp("pnode_sz %d", c->pnode_sz);
835 dbg_lp("nnode_sz %d", c->nnode_sz);
836 dbg_lp("ltab_sz %d", c->ltab_sz);
837 dbg_lp("lsave_sz %d", c->lsave_sz);
838 dbg_lp("lsave_cnt %d", c->lsave_cnt);
839 dbg_lp("lpt_hght %d", c->lpt_hght);
840 dbg_lp("big_lpt %d", c->big_lpt);
841 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
842 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
843 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
844 if (c->big_lpt)
845 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
846 out:
847 c->ltab = NULL;
848 kfree(lsave);
849 vfree(ltab);
850 vfree(buf);
851 kfree(nnode);
852 kfree(pnode);
853 return err;
854 }
855
856 /**
857 * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
858 * @c: UBIFS file-system description object
859 * @pnode: pnode
860 *
861 * When a pnode is loaded into memory, the LEB properties it contains are added,
862 * by this function, to the LEB category lists and heaps.
863 */
update_cats(struct ubifs_info * c,struct ubifs_pnode * pnode)864 static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
865 {
866 int i;
867
868 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
869 int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
870 int lnum = pnode->lprops[i].lnum;
871
872 if (!lnum)
873 return;
874 ubifs_add_to_cat(c, &pnode->lprops[i], cat);
875 }
876 }
877
878 /**
879 * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
880 * @c: UBIFS file-system description object
881 * @old_pnode: pnode copied
882 * @new_pnode: pnode copy
883 *
884 * During commit it is sometimes necessary to copy a pnode
885 * (see dirty_cow_pnode). When that happens, references in
886 * category lists and heaps must be replaced. This function does that.
887 */
replace_cats(struct ubifs_info * c,struct ubifs_pnode * old_pnode,struct ubifs_pnode * new_pnode)888 static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
889 struct ubifs_pnode *new_pnode)
890 {
891 int i;
892
893 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
894 if (!new_pnode->lprops[i].lnum)
895 return;
896 ubifs_replace_cat(c, &old_pnode->lprops[i],
897 &new_pnode->lprops[i]);
898 }
899 }
900
901 /**
902 * check_lpt_crc - check LPT node crc is correct.
903 * @c: UBIFS file-system description object
904 * @buf: buffer containing node
905 * @len: length of node
906 *
907 * This function returns %0 on success and a negative error code on failure.
908 */
check_lpt_crc(const struct ubifs_info * c,void * buf,int len)909 static int check_lpt_crc(const struct ubifs_info *c, void *buf, int len)
910 {
911 int pos = 0;
912 uint8_t *addr = buf;
913 uint16_t crc, calc_crc;
914
915 crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
916 calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
917 len - UBIFS_LPT_CRC_BYTES);
918 if (crc != calc_crc) {
919 ubifs_err(c, "invalid crc in LPT node: crc %hx calc %hx",
920 crc, calc_crc);
921 dump_stack();
922 return -EINVAL;
923 }
924 return 0;
925 }
926
927 /**
928 * check_lpt_type - check LPT node type is correct.
929 * @c: UBIFS file-system description object
930 * @addr: address of type bit field is passed and returned updated here
931 * @pos: position of type bit field is passed and returned updated here
932 * @type: expected type
933 *
934 * This function returns %0 on success and a negative error code on failure.
935 */
check_lpt_type(const struct ubifs_info * c,uint8_t ** addr,int * pos,int type)936 static int check_lpt_type(const struct ubifs_info *c, uint8_t **addr,
937 int *pos, int type)
938 {
939 int node_type;
940
941 node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
942 if (node_type != type) {
943 ubifs_err(c, "invalid type (%d) in LPT node type %d",
944 node_type, type);
945 dump_stack();
946 return -EINVAL;
947 }
948 return 0;
949 }
950
951 /**
952 * unpack_pnode - unpack a pnode.
953 * @c: UBIFS file-system description object
954 * @buf: buffer containing packed pnode to unpack
955 * @pnode: pnode structure to fill
956 *
957 * This function returns %0 on success and a negative error code on failure.
958 */
unpack_pnode(const struct ubifs_info * c,void * buf,struct ubifs_pnode * pnode)959 static int unpack_pnode(const struct ubifs_info *c, void *buf,
960 struct ubifs_pnode *pnode)
961 {
962 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
963 int i, pos = 0, err;
964
965 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_PNODE);
966 if (err)
967 return err;
968 if (c->big_lpt)
969 pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
970 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
971 struct ubifs_lprops * const lprops = &pnode->lprops[i];
972
973 lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
974 lprops->free <<= 3;
975 lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
976 lprops->dirty <<= 3;
977
978 if (ubifs_unpack_bits(&addr, &pos, 1))
979 lprops->flags = LPROPS_INDEX;
980 else
981 lprops->flags = 0;
982 lprops->flags |= ubifs_categorize_lprops(c, lprops);
983 }
984 err = check_lpt_crc(c, buf, c->pnode_sz);
985 return err;
986 }
987
988 /**
989 * ubifs_unpack_nnode - unpack a nnode.
990 * @c: UBIFS file-system description object
991 * @buf: buffer containing packed nnode to unpack
992 * @nnode: nnode structure to fill
993 *
994 * This function returns %0 on success and a negative error code on failure.
995 */
ubifs_unpack_nnode(const struct ubifs_info * c,void * buf,struct ubifs_nnode * nnode)996 int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
997 struct ubifs_nnode *nnode)
998 {
999 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1000 int i, pos = 0, err;
1001
1002 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_NNODE);
1003 if (err)
1004 return err;
1005 if (c->big_lpt)
1006 nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
1007 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1008 int lnum;
1009
1010 lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
1011 c->lpt_first;
1012 if (lnum == c->lpt_last + 1)
1013 lnum = 0;
1014 nnode->nbranch[i].lnum = lnum;
1015 nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
1016 c->lpt_offs_bits);
1017 }
1018 err = check_lpt_crc(c, buf, c->nnode_sz);
1019 return err;
1020 }
1021
1022 /**
1023 * unpack_ltab - unpack the LPT's own lprops table.
1024 * @c: UBIFS file-system description object
1025 * @buf: buffer from which to unpack
1026 *
1027 * This function returns %0 on success and a negative error code on failure.
1028 */
unpack_ltab(const struct ubifs_info * c,void * buf)1029 static int unpack_ltab(const struct ubifs_info *c, void *buf)
1030 {
1031 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1032 int i, pos = 0, err;
1033
1034 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LTAB);
1035 if (err)
1036 return err;
1037 for (i = 0; i < c->lpt_lebs; i++) {
1038 int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1039 int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1040
1041 if (free < 0 || free > c->leb_size || dirty < 0 ||
1042 dirty > c->leb_size || free + dirty > c->leb_size)
1043 return -EINVAL;
1044
1045 c->ltab[i].free = free;
1046 c->ltab[i].dirty = dirty;
1047 c->ltab[i].tgc = 0;
1048 c->ltab[i].cmt = 0;
1049 }
1050 err = check_lpt_crc(c, buf, c->ltab_sz);
1051 return err;
1052 }
1053
1054 #ifndef __UBOOT__
1055 /**
1056 * unpack_lsave - unpack the LPT's save table.
1057 * @c: UBIFS file-system description object
1058 * @buf: buffer from which to unpack
1059 *
1060 * This function returns %0 on success and a negative error code on failure.
1061 */
unpack_lsave(const struct ubifs_info * c,void * buf)1062 static int unpack_lsave(const struct ubifs_info *c, void *buf)
1063 {
1064 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1065 int i, pos = 0, err;
1066
1067 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LSAVE);
1068 if (err)
1069 return err;
1070 for (i = 0; i < c->lsave_cnt; i++) {
1071 int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits);
1072
1073 if (lnum < c->main_first || lnum >= c->leb_cnt)
1074 return -EINVAL;
1075 c->lsave[i] = lnum;
1076 }
1077 err = check_lpt_crc(c, buf, c->lsave_sz);
1078 return err;
1079 }
1080 #endif
1081
1082 /**
1083 * validate_nnode - validate a nnode.
1084 * @c: UBIFS file-system description object
1085 * @nnode: nnode to validate
1086 * @parent: parent nnode (or NULL for the root nnode)
1087 * @iip: index in parent
1088 *
1089 * This function returns %0 on success and a negative error code on failure.
1090 */
validate_nnode(const struct ubifs_info * c,struct ubifs_nnode * nnode,struct ubifs_nnode * parent,int iip)1091 static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode,
1092 struct ubifs_nnode *parent, int iip)
1093 {
1094 int i, lvl, max_offs;
1095
1096 if (c->big_lpt) {
1097 int num = calc_nnode_num_from_parent(c, parent, iip);
1098
1099 if (nnode->num != num)
1100 return -EINVAL;
1101 }
1102 lvl = parent ? parent->level - 1 : c->lpt_hght;
1103 if (lvl < 1)
1104 return -EINVAL;
1105 if (lvl == 1)
1106 max_offs = c->leb_size - c->pnode_sz;
1107 else
1108 max_offs = c->leb_size - c->nnode_sz;
1109 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1110 int lnum = nnode->nbranch[i].lnum;
1111 int offs = nnode->nbranch[i].offs;
1112
1113 if (lnum == 0) {
1114 if (offs != 0)
1115 return -EINVAL;
1116 continue;
1117 }
1118 if (lnum < c->lpt_first || lnum > c->lpt_last)
1119 return -EINVAL;
1120 if (offs < 0 || offs > max_offs)
1121 return -EINVAL;
1122 }
1123 return 0;
1124 }
1125
1126 /**
1127 * validate_pnode - validate a pnode.
1128 * @c: UBIFS file-system description object
1129 * @pnode: pnode to validate
1130 * @parent: parent nnode
1131 * @iip: index in parent
1132 *
1133 * This function returns %0 on success and a negative error code on failure.
1134 */
validate_pnode(const struct ubifs_info * c,struct ubifs_pnode * pnode,struct ubifs_nnode * parent,int iip)1135 static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode,
1136 struct ubifs_nnode *parent, int iip)
1137 {
1138 int i;
1139
1140 if (c->big_lpt) {
1141 int num = calc_pnode_num_from_parent(c, parent, iip);
1142
1143 if (pnode->num != num)
1144 return -EINVAL;
1145 }
1146 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1147 int free = pnode->lprops[i].free;
1148 int dirty = pnode->lprops[i].dirty;
1149
1150 if (free < 0 || free > c->leb_size || free % c->min_io_size ||
1151 (free & 7))
1152 return -EINVAL;
1153 if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
1154 return -EINVAL;
1155 if (dirty + free > c->leb_size)
1156 return -EINVAL;
1157 }
1158 return 0;
1159 }
1160
1161 /**
1162 * set_pnode_lnum - set LEB numbers on a pnode.
1163 * @c: UBIFS file-system description object
1164 * @pnode: pnode to update
1165 *
1166 * This function calculates the LEB numbers for the LEB properties it contains
1167 * based on the pnode number.
1168 */
set_pnode_lnum(const struct ubifs_info * c,struct ubifs_pnode * pnode)1169 static void set_pnode_lnum(const struct ubifs_info *c,
1170 struct ubifs_pnode *pnode)
1171 {
1172 int i, lnum;
1173
1174 lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
1175 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1176 if (lnum >= c->leb_cnt)
1177 return;
1178 pnode->lprops[i].lnum = lnum++;
1179 }
1180 }
1181
1182 /**
1183 * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
1184 * @c: UBIFS file-system description object
1185 * @parent: parent nnode (or NULL for the root)
1186 * @iip: index in parent
1187 *
1188 * This function returns %0 on success and a negative error code on failure.
1189 */
ubifs_read_nnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1190 int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1191 {
1192 struct ubifs_nbranch *branch = NULL;
1193 struct ubifs_nnode *nnode = NULL;
1194 void *buf = c->lpt_nod_buf;
1195 int err, lnum, offs;
1196
1197 if (parent) {
1198 branch = &parent->nbranch[iip];
1199 lnum = branch->lnum;
1200 offs = branch->offs;
1201 } else {
1202 lnum = c->lpt_lnum;
1203 offs = c->lpt_offs;
1204 }
1205 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1206 if (!nnode) {
1207 err = -ENOMEM;
1208 goto out;
1209 }
1210 if (lnum == 0) {
1211 /*
1212 * This nnode was not written which just means that the LEB
1213 * properties in the subtree below it describe empty LEBs. We
1214 * make the nnode as though we had read it, which in fact means
1215 * doing almost nothing.
1216 */
1217 if (c->big_lpt)
1218 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1219 } else {
1220 err = ubifs_leb_read(c, lnum, buf, offs, c->nnode_sz, 1);
1221 if (err)
1222 goto out;
1223 err = ubifs_unpack_nnode(c, buf, nnode);
1224 if (err)
1225 goto out;
1226 }
1227 err = validate_nnode(c, nnode, parent, iip);
1228 if (err)
1229 goto out;
1230 if (!c->big_lpt)
1231 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1232 if (parent) {
1233 branch->nnode = nnode;
1234 nnode->level = parent->level - 1;
1235 } else {
1236 c->nroot = nnode;
1237 nnode->level = c->lpt_hght;
1238 }
1239 nnode->parent = parent;
1240 nnode->iip = iip;
1241 return 0;
1242
1243 out:
1244 ubifs_err(c, "error %d reading nnode at %d:%d", err, lnum, offs);
1245 dump_stack();
1246 kfree(nnode);
1247 return err;
1248 }
1249
1250 /**
1251 * read_pnode - read a pnode from flash and link it to the tree in memory.
1252 * @c: UBIFS file-system description object
1253 * @parent: parent nnode
1254 * @iip: index in parent
1255 *
1256 * This function returns %0 on success and a negative error code on failure.
1257 */
read_pnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1258 static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1259 {
1260 struct ubifs_nbranch *branch;
1261 struct ubifs_pnode *pnode = NULL;
1262 void *buf = c->lpt_nod_buf;
1263 int err, lnum, offs;
1264
1265 branch = &parent->nbranch[iip];
1266 lnum = branch->lnum;
1267 offs = branch->offs;
1268 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1269 if (!pnode)
1270 return -ENOMEM;
1271
1272 if (lnum == 0) {
1273 /*
1274 * This pnode was not written which just means that the LEB
1275 * properties in it describe empty LEBs. We make the pnode as
1276 * though we had read it.
1277 */
1278 int i;
1279
1280 if (c->big_lpt)
1281 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1282 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1283 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1284
1285 lprops->free = c->leb_size;
1286 lprops->flags = ubifs_categorize_lprops(c, lprops);
1287 }
1288 } else {
1289 err = ubifs_leb_read(c, lnum, buf, offs, c->pnode_sz, 1);
1290 if (err)
1291 goto out;
1292 err = unpack_pnode(c, buf, pnode);
1293 if (err)
1294 goto out;
1295 }
1296 err = validate_pnode(c, pnode, parent, iip);
1297 if (err)
1298 goto out;
1299 if (!c->big_lpt)
1300 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1301 branch->pnode = pnode;
1302 pnode->parent = parent;
1303 pnode->iip = iip;
1304 set_pnode_lnum(c, pnode);
1305 c->pnodes_have += 1;
1306 return 0;
1307
1308 out:
1309 ubifs_err(c, "error %d reading pnode at %d:%d", err, lnum, offs);
1310 ubifs_dump_pnode(c, pnode, parent, iip);
1311 dump_stack();
1312 ubifs_err(c, "calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
1313 kfree(pnode);
1314 return err;
1315 }
1316
1317 /**
1318 * read_ltab - read LPT's own lprops table.
1319 * @c: UBIFS file-system description object
1320 *
1321 * This function returns %0 on success and a negative error code on failure.
1322 */
read_ltab(struct ubifs_info * c)1323 static int read_ltab(struct ubifs_info *c)
1324 {
1325 int err;
1326 void *buf;
1327
1328 buf = vmalloc(c->ltab_sz);
1329 if (!buf)
1330 return -ENOMEM;
1331 err = ubifs_leb_read(c, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz, 1);
1332 if (err)
1333 goto out;
1334 err = unpack_ltab(c, buf);
1335 out:
1336 vfree(buf);
1337 return err;
1338 }
1339
1340 #ifndef __UBOOT__
1341 /**
1342 * read_lsave - read LPT's save table.
1343 * @c: UBIFS file-system description object
1344 *
1345 * This function returns %0 on success and a negative error code on failure.
1346 */
read_lsave(struct ubifs_info * c)1347 static int read_lsave(struct ubifs_info *c)
1348 {
1349 int err, i;
1350 void *buf;
1351
1352 buf = vmalloc(c->lsave_sz);
1353 if (!buf)
1354 return -ENOMEM;
1355 err = ubifs_leb_read(c, c->lsave_lnum, buf, c->lsave_offs,
1356 c->lsave_sz, 1);
1357 if (err)
1358 goto out;
1359 err = unpack_lsave(c, buf);
1360 if (err)
1361 goto out;
1362 for (i = 0; i < c->lsave_cnt; i++) {
1363 int lnum = c->lsave[i];
1364 struct ubifs_lprops *lprops;
1365
1366 /*
1367 * Due to automatic resizing, the values in the lsave table
1368 * could be beyond the volume size - just ignore them.
1369 */
1370 if (lnum >= c->leb_cnt)
1371 continue;
1372 lprops = ubifs_lpt_lookup(c, lnum);
1373 if (IS_ERR(lprops)) {
1374 err = PTR_ERR(lprops);
1375 goto out;
1376 }
1377 }
1378 out:
1379 vfree(buf);
1380 return err;
1381 }
1382 #endif
1383
1384 /**
1385 * ubifs_get_nnode - get a nnode.
1386 * @c: UBIFS file-system description object
1387 * @parent: parent nnode (or NULL for the root)
1388 * @iip: index in parent
1389 *
1390 * This function returns a pointer to the nnode on success or a negative error
1391 * code on failure.
1392 */
ubifs_get_nnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1393 struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
1394 struct ubifs_nnode *parent, int iip)
1395 {
1396 struct ubifs_nbranch *branch;
1397 struct ubifs_nnode *nnode;
1398 int err;
1399
1400 branch = &parent->nbranch[iip];
1401 nnode = branch->nnode;
1402 if (nnode)
1403 return nnode;
1404 err = ubifs_read_nnode(c, parent, iip);
1405 if (err)
1406 return ERR_PTR(err);
1407 return branch->nnode;
1408 }
1409
1410 /**
1411 * ubifs_get_pnode - get a pnode.
1412 * @c: UBIFS file-system description object
1413 * @parent: parent nnode
1414 * @iip: index in parent
1415 *
1416 * This function returns a pointer to the pnode on success or a negative error
1417 * code on failure.
1418 */
ubifs_get_pnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1419 struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
1420 struct ubifs_nnode *parent, int iip)
1421 {
1422 struct ubifs_nbranch *branch;
1423 struct ubifs_pnode *pnode;
1424 int err;
1425
1426 branch = &parent->nbranch[iip];
1427 pnode = branch->pnode;
1428 if (pnode)
1429 return pnode;
1430 err = read_pnode(c, parent, iip);
1431 if (err)
1432 return ERR_PTR(err);
1433 update_cats(c, branch->pnode);
1434 return branch->pnode;
1435 }
1436
1437 /**
1438 * ubifs_lpt_lookup - lookup LEB properties in the LPT.
1439 * @c: UBIFS file-system description object
1440 * @lnum: LEB number to lookup
1441 *
1442 * This function returns a pointer to the LEB properties on success or a
1443 * negative error code on failure.
1444 */
ubifs_lpt_lookup(struct ubifs_info * c,int lnum)1445 struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
1446 {
1447 int err, i, h, iip, shft;
1448 struct ubifs_nnode *nnode;
1449 struct ubifs_pnode *pnode;
1450
1451 if (!c->nroot) {
1452 err = ubifs_read_nnode(c, NULL, 0);
1453 if (err)
1454 return ERR_PTR(err);
1455 }
1456 nnode = c->nroot;
1457 i = lnum - c->main_first;
1458 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1459 for (h = 1; h < c->lpt_hght; h++) {
1460 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1461 shft -= UBIFS_LPT_FANOUT_SHIFT;
1462 nnode = ubifs_get_nnode(c, nnode, iip);
1463 if (IS_ERR(nnode))
1464 return ERR_CAST(nnode);
1465 }
1466 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1467 pnode = ubifs_get_pnode(c, nnode, iip);
1468 if (IS_ERR(pnode))
1469 return ERR_CAST(pnode);
1470 iip = (i & (UBIFS_LPT_FANOUT - 1));
1471 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1472 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1473 pnode->lprops[iip].flags);
1474 return &pnode->lprops[iip];
1475 }
1476
1477 /**
1478 * dirty_cow_nnode - ensure a nnode is not being committed.
1479 * @c: UBIFS file-system description object
1480 * @nnode: nnode to check
1481 *
1482 * Returns dirtied nnode on success or negative error code on failure.
1483 */
dirty_cow_nnode(struct ubifs_info * c,struct ubifs_nnode * nnode)1484 static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
1485 struct ubifs_nnode *nnode)
1486 {
1487 struct ubifs_nnode *n;
1488 int i;
1489
1490 if (!test_bit(COW_CNODE, &nnode->flags)) {
1491 /* nnode is not being committed */
1492 if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
1493 c->dirty_nn_cnt += 1;
1494 ubifs_add_nnode_dirt(c, nnode);
1495 }
1496 return nnode;
1497 }
1498
1499 /* nnode is being committed, so copy it */
1500 n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1501 if (unlikely(!n))
1502 return ERR_PTR(-ENOMEM);
1503
1504 memcpy(n, nnode, sizeof(struct ubifs_nnode));
1505 n->cnext = NULL;
1506 __set_bit(DIRTY_CNODE, &n->flags);
1507 __clear_bit(COW_CNODE, &n->flags);
1508
1509 /* The children now have new parent */
1510 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1511 struct ubifs_nbranch *branch = &n->nbranch[i];
1512
1513 if (branch->cnode)
1514 branch->cnode->parent = n;
1515 }
1516
1517 ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
1518 __set_bit(OBSOLETE_CNODE, &nnode->flags);
1519
1520 c->dirty_nn_cnt += 1;
1521 ubifs_add_nnode_dirt(c, nnode);
1522 if (nnode->parent)
1523 nnode->parent->nbranch[n->iip].nnode = n;
1524 else
1525 c->nroot = n;
1526 return n;
1527 }
1528
1529 /**
1530 * dirty_cow_pnode - ensure a pnode is not being committed.
1531 * @c: UBIFS file-system description object
1532 * @pnode: pnode to check
1533 *
1534 * Returns dirtied pnode on success or negative error code on failure.
1535 */
dirty_cow_pnode(struct ubifs_info * c,struct ubifs_pnode * pnode)1536 static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
1537 struct ubifs_pnode *pnode)
1538 {
1539 struct ubifs_pnode *p;
1540
1541 if (!test_bit(COW_CNODE, &pnode->flags)) {
1542 /* pnode is not being committed */
1543 if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
1544 c->dirty_pn_cnt += 1;
1545 add_pnode_dirt(c, pnode);
1546 }
1547 return pnode;
1548 }
1549
1550 /* pnode is being committed, so copy it */
1551 p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1552 if (unlikely(!p))
1553 return ERR_PTR(-ENOMEM);
1554
1555 memcpy(p, pnode, sizeof(struct ubifs_pnode));
1556 p->cnext = NULL;
1557 __set_bit(DIRTY_CNODE, &p->flags);
1558 __clear_bit(COW_CNODE, &p->flags);
1559 replace_cats(c, pnode, p);
1560
1561 ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
1562 __set_bit(OBSOLETE_CNODE, &pnode->flags);
1563
1564 c->dirty_pn_cnt += 1;
1565 add_pnode_dirt(c, pnode);
1566 pnode->parent->nbranch[p->iip].pnode = p;
1567 return p;
1568 }
1569
1570 /**
1571 * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
1572 * @c: UBIFS file-system description object
1573 * @lnum: LEB number to lookup
1574 *
1575 * This function returns a pointer to the LEB properties on success or a
1576 * negative error code on failure.
1577 */
ubifs_lpt_lookup_dirty(struct ubifs_info * c,int lnum)1578 struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
1579 {
1580 int err, i, h, iip, shft;
1581 struct ubifs_nnode *nnode;
1582 struct ubifs_pnode *pnode;
1583
1584 if (!c->nroot) {
1585 err = ubifs_read_nnode(c, NULL, 0);
1586 if (err)
1587 return ERR_PTR(err);
1588 }
1589 nnode = c->nroot;
1590 nnode = dirty_cow_nnode(c, nnode);
1591 if (IS_ERR(nnode))
1592 return ERR_CAST(nnode);
1593 i = lnum - c->main_first;
1594 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1595 for (h = 1; h < c->lpt_hght; h++) {
1596 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1597 shft -= UBIFS_LPT_FANOUT_SHIFT;
1598 nnode = ubifs_get_nnode(c, nnode, iip);
1599 if (IS_ERR(nnode))
1600 return ERR_CAST(nnode);
1601 nnode = dirty_cow_nnode(c, nnode);
1602 if (IS_ERR(nnode))
1603 return ERR_CAST(nnode);
1604 }
1605 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1606 pnode = ubifs_get_pnode(c, nnode, iip);
1607 if (IS_ERR(pnode))
1608 return ERR_CAST(pnode);
1609 pnode = dirty_cow_pnode(c, pnode);
1610 if (IS_ERR(pnode))
1611 return ERR_CAST(pnode);
1612 iip = (i & (UBIFS_LPT_FANOUT - 1));
1613 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1614 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1615 pnode->lprops[iip].flags);
1616 ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
1617 return &pnode->lprops[iip];
1618 }
1619
1620 /**
1621 * lpt_init_rd - initialize the LPT for reading.
1622 * @c: UBIFS file-system description object
1623 *
1624 * This function returns %0 on success and a negative error code on failure.
1625 */
lpt_init_rd(struct ubifs_info * c)1626 static int lpt_init_rd(struct ubifs_info *c)
1627 {
1628 int err, i;
1629
1630 c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1631 if (!c->ltab)
1632 return -ENOMEM;
1633
1634 i = max_t(int, c->nnode_sz, c->pnode_sz);
1635 c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
1636 if (!c->lpt_nod_buf)
1637 return -ENOMEM;
1638
1639 for (i = 0; i < LPROPS_HEAP_CNT; i++) {
1640 c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
1641 GFP_KERNEL);
1642 if (!c->lpt_heap[i].arr)
1643 return -ENOMEM;
1644 c->lpt_heap[i].cnt = 0;
1645 c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
1646 }
1647
1648 c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
1649 if (!c->dirty_idx.arr)
1650 return -ENOMEM;
1651 c->dirty_idx.cnt = 0;
1652 c->dirty_idx.max_cnt = LPT_HEAP_SZ;
1653
1654 err = read_ltab(c);
1655 if (err)
1656 return err;
1657
1658 dbg_lp("space_bits %d", c->space_bits);
1659 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
1660 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
1661 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
1662 dbg_lp("pcnt_bits %d", c->pcnt_bits);
1663 dbg_lp("lnum_bits %d", c->lnum_bits);
1664 dbg_lp("pnode_sz %d", c->pnode_sz);
1665 dbg_lp("nnode_sz %d", c->nnode_sz);
1666 dbg_lp("ltab_sz %d", c->ltab_sz);
1667 dbg_lp("lsave_sz %d", c->lsave_sz);
1668 dbg_lp("lsave_cnt %d", c->lsave_cnt);
1669 dbg_lp("lpt_hght %d", c->lpt_hght);
1670 dbg_lp("big_lpt %d", c->big_lpt);
1671 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
1672 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
1673 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
1674 if (c->big_lpt)
1675 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
1676
1677 return 0;
1678 }
1679
1680 #ifndef __UBOOT__
1681 /**
1682 * lpt_init_wr - initialize the LPT for writing.
1683 * @c: UBIFS file-system description object
1684 *
1685 * 'lpt_init_rd()' must have been called already.
1686 *
1687 * This function returns %0 on success and a negative error code on failure.
1688 */
lpt_init_wr(struct ubifs_info * c)1689 static int lpt_init_wr(struct ubifs_info *c)
1690 {
1691 int err, i;
1692
1693 c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1694 if (!c->ltab_cmt)
1695 return -ENOMEM;
1696
1697 c->lpt_buf = vmalloc(c->leb_size);
1698 if (!c->lpt_buf)
1699 return -ENOMEM;
1700
1701 if (c->big_lpt) {
1702 c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
1703 if (!c->lsave)
1704 return -ENOMEM;
1705 err = read_lsave(c);
1706 if (err)
1707 return err;
1708 }
1709
1710 for (i = 0; i < c->lpt_lebs; i++)
1711 if (c->ltab[i].free == c->leb_size) {
1712 err = ubifs_leb_unmap(c, i + c->lpt_first);
1713 if (err)
1714 return err;
1715 }
1716
1717 return 0;
1718 }
1719 #endif
1720
1721 /**
1722 * ubifs_lpt_init - initialize the LPT.
1723 * @c: UBIFS file-system description object
1724 * @rd: whether to initialize lpt for reading
1725 * @wr: whether to initialize lpt for writing
1726 *
1727 * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
1728 * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
1729 * true.
1730 *
1731 * This function returns %0 on success and a negative error code on failure.
1732 */
ubifs_lpt_init(struct ubifs_info * c,int rd,int wr)1733 int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
1734 {
1735 int err;
1736
1737 if (rd) {
1738 err = lpt_init_rd(c);
1739 if (err)
1740 goto out_err;
1741 }
1742
1743 #ifndef __UBOOT__
1744 if (wr) {
1745 err = lpt_init_wr(c);
1746 if (err)
1747 goto out_err;
1748 }
1749 #endif
1750
1751 return 0;
1752
1753 out_err:
1754 #ifndef __UBOOT__
1755 if (wr)
1756 ubifs_lpt_free(c, 1);
1757 #endif
1758 if (rd)
1759 ubifs_lpt_free(c, 0);
1760 return err;
1761 }
1762
1763 /**
1764 * struct lpt_scan_node - somewhere to put nodes while we scan LPT.
1765 * @nnode: where to keep a nnode
1766 * @pnode: where to keep a pnode
1767 * @cnode: where to keep a cnode
1768 * @in_tree: is the node in the tree in memory
1769 * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in
1770 * the tree
1771 * @ptr.pnode: ditto for pnode
1772 * @ptr.cnode: ditto for cnode
1773 */
1774 struct lpt_scan_node {
1775 union {
1776 struct ubifs_nnode nnode;
1777 struct ubifs_pnode pnode;
1778 struct ubifs_cnode cnode;
1779 };
1780 int in_tree;
1781 union {
1782 struct ubifs_nnode *nnode;
1783 struct ubifs_pnode *pnode;
1784 struct ubifs_cnode *cnode;
1785 } ptr;
1786 };
1787
1788 /**
1789 * scan_get_nnode - for the scan, get a nnode from either the tree or flash.
1790 * @c: the UBIFS file-system description object
1791 * @path: where to put the nnode
1792 * @parent: parent of the nnode
1793 * @iip: index in parent of the nnode
1794 *
1795 * This function returns a pointer to the nnode on success or a negative error
1796 * code on failure.
1797 */
scan_get_nnode(struct ubifs_info * c,struct lpt_scan_node * path,struct ubifs_nnode * parent,int iip)1798 static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
1799 struct lpt_scan_node *path,
1800 struct ubifs_nnode *parent, int iip)
1801 {
1802 struct ubifs_nbranch *branch;
1803 struct ubifs_nnode *nnode;
1804 void *buf = c->lpt_nod_buf;
1805 int err;
1806
1807 branch = &parent->nbranch[iip];
1808 nnode = branch->nnode;
1809 if (nnode) {
1810 path->in_tree = 1;
1811 path->ptr.nnode = nnode;
1812 return nnode;
1813 }
1814 nnode = &path->nnode;
1815 path->in_tree = 0;
1816 path->ptr.nnode = nnode;
1817 memset(nnode, 0, sizeof(struct ubifs_nnode));
1818 if (branch->lnum == 0) {
1819 /*
1820 * This nnode was not written which just means that the LEB
1821 * properties in the subtree below it describe empty LEBs. We
1822 * make the nnode as though we had read it, which in fact means
1823 * doing almost nothing.
1824 */
1825 if (c->big_lpt)
1826 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1827 } else {
1828 err = ubifs_leb_read(c, branch->lnum, buf, branch->offs,
1829 c->nnode_sz, 1);
1830 if (err)
1831 return ERR_PTR(err);
1832 err = ubifs_unpack_nnode(c, buf, nnode);
1833 if (err)
1834 return ERR_PTR(err);
1835 }
1836 err = validate_nnode(c, nnode, parent, iip);
1837 if (err)
1838 return ERR_PTR(err);
1839 if (!c->big_lpt)
1840 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1841 nnode->level = parent->level - 1;
1842 nnode->parent = parent;
1843 nnode->iip = iip;
1844 return nnode;
1845 }
1846
1847 /**
1848 * scan_get_pnode - for the scan, get a pnode from either the tree or flash.
1849 * @c: the UBIFS file-system description object
1850 * @path: where to put the pnode
1851 * @parent: parent of the pnode
1852 * @iip: index in parent of the pnode
1853 *
1854 * This function returns a pointer to the pnode on success or a negative error
1855 * code on failure.
1856 */
scan_get_pnode(struct ubifs_info * c,struct lpt_scan_node * path,struct ubifs_nnode * parent,int iip)1857 static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c,
1858 struct lpt_scan_node *path,
1859 struct ubifs_nnode *parent, int iip)
1860 {
1861 struct ubifs_nbranch *branch;
1862 struct ubifs_pnode *pnode;
1863 void *buf = c->lpt_nod_buf;
1864 int err;
1865
1866 branch = &parent->nbranch[iip];
1867 pnode = branch->pnode;
1868 if (pnode) {
1869 path->in_tree = 1;
1870 path->ptr.pnode = pnode;
1871 return pnode;
1872 }
1873 pnode = &path->pnode;
1874 path->in_tree = 0;
1875 path->ptr.pnode = pnode;
1876 memset(pnode, 0, sizeof(struct ubifs_pnode));
1877 if (branch->lnum == 0) {
1878 /*
1879 * This pnode was not written which just means that the LEB
1880 * properties in it describe empty LEBs. We make the pnode as
1881 * though we had read it.
1882 */
1883 int i;
1884
1885 if (c->big_lpt)
1886 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1887 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1888 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1889
1890 lprops->free = c->leb_size;
1891 lprops->flags = ubifs_categorize_lprops(c, lprops);
1892 }
1893 } else {
1894 ubifs_assert(branch->lnum >= c->lpt_first &&
1895 branch->lnum <= c->lpt_last);
1896 ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size);
1897 err = ubifs_leb_read(c, branch->lnum, buf, branch->offs,
1898 c->pnode_sz, 1);
1899 if (err)
1900 return ERR_PTR(err);
1901 err = unpack_pnode(c, buf, pnode);
1902 if (err)
1903 return ERR_PTR(err);
1904 }
1905 err = validate_pnode(c, pnode, parent, iip);
1906 if (err)
1907 return ERR_PTR(err);
1908 if (!c->big_lpt)
1909 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1910 pnode->parent = parent;
1911 pnode->iip = iip;
1912 set_pnode_lnum(c, pnode);
1913 return pnode;
1914 }
1915
1916 /**
1917 * ubifs_lpt_scan_nolock - scan the LPT.
1918 * @c: the UBIFS file-system description object
1919 * @start_lnum: LEB number from which to start scanning
1920 * @end_lnum: LEB number at which to stop scanning
1921 * @scan_cb: callback function called for each lprops
1922 * @data: data to be passed to the callback function
1923 *
1924 * This function returns %0 on success and a negative error code on failure.
1925 */
ubifs_lpt_scan_nolock(struct ubifs_info * c,int start_lnum,int end_lnum,ubifs_lpt_scan_callback scan_cb,void * data)1926 int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
1927 ubifs_lpt_scan_callback scan_cb, void *data)
1928 {
1929 int err = 0, i, h, iip, shft;
1930 struct ubifs_nnode *nnode;
1931 struct ubifs_pnode *pnode;
1932 struct lpt_scan_node *path;
1933
1934 if (start_lnum == -1) {
1935 start_lnum = end_lnum + 1;
1936 if (start_lnum >= c->leb_cnt)
1937 start_lnum = c->main_first;
1938 }
1939
1940 ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt);
1941 ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt);
1942
1943 if (!c->nroot) {
1944 err = ubifs_read_nnode(c, NULL, 0);
1945 if (err)
1946 return err;
1947 }
1948
1949 path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
1950 GFP_NOFS);
1951 if (!path)
1952 return -ENOMEM;
1953
1954 path[0].ptr.nnode = c->nroot;
1955 path[0].in_tree = 1;
1956 again:
1957 /* Descend to the pnode containing start_lnum */
1958 nnode = c->nroot;
1959 i = start_lnum - c->main_first;
1960 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1961 for (h = 1; h < c->lpt_hght; h++) {
1962 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1963 shft -= UBIFS_LPT_FANOUT_SHIFT;
1964 nnode = scan_get_nnode(c, path + h, nnode, iip);
1965 if (IS_ERR(nnode)) {
1966 err = PTR_ERR(nnode);
1967 goto out;
1968 }
1969 }
1970 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1971 pnode = scan_get_pnode(c, path + h, nnode, iip);
1972 if (IS_ERR(pnode)) {
1973 err = PTR_ERR(pnode);
1974 goto out;
1975 }
1976 iip = (i & (UBIFS_LPT_FANOUT - 1));
1977
1978 /* Loop for each lprops */
1979 while (1) {
1980 struct ubifs_lprops *lprops = &pnode->lprops[iip];
1981 int ret, lnum = lprops->lnum;
1982
1983 ret = scan_cb(c, lprops, path[h].in_tree, data);
1984 if (ret < 0) {
1985 err = ret;
1986 goto out;
1987 }
1988 if (ret & LPT_SCAN_ADD) {
1989 /* Add all the nodes in path to the tree in memory */
1990 for (h = 1; h < c->lpt_hght; h++) {
1991 const size_t sz = sizeof(struct ubifs_nnode);
1992 struct ubifs_nnode *parent;
1993
1994 if (path[h].in_tree)
1995 continue;
1996 nnode = kmemdup(&path[h].nnode, sz, GFP_NOFS);
1997 if (!nnode) {
1998 err = -ENOMEM;
1999 goto out;
2000 }
2001 parent = nnode->parent;
2002 parent->nbranch[nnode->iip].nnode = nnode;
2003 path[h].ptr.nnode = nnode;
2004 path[h].in_tree = 1;
2005 path[h + 1].cnode.parent = nnode;
2006 }
2007 if (path[h].in_tree)
2008 ubifs_ensure_cat(c, lprops);
2009 else {
2010 const size_t sz = sizeof(struct ubifs_pnode);
2011 struct ubifs_nnode *parent;
2012
2013 pnode = kmemdup(&path[h].pnode, sz, GFP_NOFS);
2014 if (!pnode) {
2015 err = -ENOMEM;
2016 goto out;
2017 }
2018 parent = pnode->parent;
2019 parent->nbranch[pnode->iip].pnode = pnode;
2020 path[h].ptr.pnode = pnode;
2021 path[h].in_tree = 1;
2022 update_cats(c, pnode);
2023 c->pnodes_have += 1;
2024 }
2025 err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)
2026 c->nroot, 0, 0);
2027 if (err)
2028 goto out;
2029 err = dbg_check_cats(c);
2030 if (err)
2031 goto out;
2032 }
2033 if (ret & LPT_SCAN_STOP) {
2034 err = 0;
2035 break;
2036 }
2037 /* Get the next lprops */
2038 if (lnum == end_lnum) {
2039 /*
2040 * We got to the end without finding what we were
2041 * looking for
2042 */
2043 err = -ENOSPC;
2044 goto out;
2045 }
2046 if (lnum + 1 >= c->leb_cnt) {
2047 /* Wrap-around to the beginning */
2048 start_lnum = c->main_first;
2049 goto again;
2050 }
2051 if (iip + 1 < UBIFS_LPT_FANOUT) {
2052 /* Next lprops is in the same pnode */
2053 iip += 1;
2054 continue;
2055 }
2056 /* We need to get the next pnode. Go up until we can go right */
2057 iip = pnode->iip;
2058 while (1) {
2059 h -= 1;
2060 ubifs_assert(h >= 0);
2061 nnode = path[h].ptr.nnode;
2062 if (iip + 1 < UBIFS_LPT_FANOUT)
2063 break;
2064 iip = nnode->iip;
2065 }
2066 /* Go right */
2067 iip += 1;
2068 /* Descend to the pnode */
2069 h += 1;
2070 for (; h < c->lpt_hght; h++) {
2071 nnode = scan_get_nnode(c, path + h, nnode, iip);
2072 if (IS_ERR(nnode)) {
2073 err = PTR_ERR(nnode);
2074 goto out;
2075 }
2076 iip = 0;
2077 }
2078 pnode = scan_get_pnode(c, path + h, nnode, iip);
2079 if (IS_ERR(pnode)) {
2080 err = PTR_ERR(pnode);
2081 goto out;
2082 }
2083 iip = 0;
2084 }
2085 out:
2086 kfree(path);
2087 return err;
2088 }
2089
2090 /**
2091 * dbg_chk_pnode - check a pnode.
2092 * @c: the UBIFS file-system description object
2093 * @pnode: pnode to check
2094 * @col: pnode column
2095 *
2096 * This function returns %0 on success and a negative error code on failure.
2097 */
dbg_chk_pnode(struct ubifs_info * c,struct ubifs_pnode * pnode,int col)2098 static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
2099 int col)
2100 {
2101 int i;
2102
2103 if (pnode->num != col) {
2104 ubifs_err(c, "pnode num %d expected %d parent num %d iip %d",
2105 pnode->num, col, pnode->parent->num, pnode->iip);
2106 return -EINVAL;
2107 }
2108 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
2109 struct ubifs_lprops *lp, *lprops = &pnode->lprops[i];
2110 int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i +
2111 c->main_first;
2112 int found, cat = lprops->flags & LPROPS_CAT_MASK;
2113 struct ubifs_lpt_heap *heap;
2114 struct list_head *list = NULL;
2115
2116 if (lnum >= c->leb_cnt)
2117 continue;
2118 if (lprops->lnum != lnum) {
2119 ubifs_err(c, "bad LEB number %d expected %d",
2120 lprops->lnum, lnum);
2121 return -EINVAL;
2122 }
2123 if (lprops->flags & LPROPS_TAKEN) {
2124 if (cat != LPROPS_UNCAT) {
2125 ubifs_err(c, "LEB %d taken but not uncat %d",
2126 lprops->lnum, cat);
2127 return -EINVAL;
2128 }
2129 continue;
2130 }
2131 if (lprops->flags & LPROPS_INDEX) {
2132 switch (cat) {
2133 case LPROPS_UNCAT:
2134 case LPROPS_DIRTY_IDX:
2135 case LPROPS_FRDI_IDX:
2136 break;
2137 default:
2138 ubifs_err(c, "LEB %d index but cat %d",
2139 lprops->lnum, cat);
2140 return -EINVAL;
2141 }
2142 } else {
2143 switch (cat) {
2144 case LPROPS_UNCAT:
2145 case LPROPS_DIRTY:
2146 case LPROPS_FREE:
2147 case LPROPS_EMPTY:
2148 case LPROPS_FREEABLE:
2149 break;
2150 default:
2151 ubifs_err(c, "LEB %d not index but cat %d",
2152 lprops->lnum, cat);
2153 return -EINVAL;
2154 }
2155 }
2156 switch (cat) {
2157 case LPROPS_UNCAT:
2158 list = &c->uncat_list;
2159 break;
2160 case LPROPS_EMPTY:
2161 list = &c->empty_list;
2162 break;
2163 case LPROPS_FREEABLE:
2164 list = &c->freeable_list;
2165 break;
2166 case LPROPS_FRDI_IDX:
2167 list = &c->frdi_idx_list;
2168 break;
2169 }
2170 found = 0;
2171 switch (cat) {
2172 case LPROPS_DIRTY:
2173 case LPROPS_DIRTY_IDX:
2174 case LPROPS_FREE:
2175 heap = &c->lpt_heap[cat - 1];
2176 if (lprops->hpos < heap->cnt &&
2177 heap->arr[lprops->hpos] == lprops)
2178 found = 1;
2179 break;
2180 case LPROPS_UNCAT:
2181 case LPROPS_EMPTY:
2182 case LPROPS_FREEABLE:
2183 case LPROPS_FRDI_IDX:
2184 list_for_each_entry(lp, list, list)
2185 if (lprops == lp) {
2186 found = 1;
2187 break;
2188 }
2189 break;
2190 }
2191 if (!found) {
2192 ubifs_err(c, "LEB %d cat %d not found in cat heap/list",
2193 lprops->lnum, cat);
2194 return -EINVAL;
2195 }
2196 switch (cat) {
2197 case LPROPS_EMPTY:
2198 if (lprops->free != c->leb_size) {
2199 ubifs_err(c, "LEB %d cat %d free %d dirty %d",
2200 lprops->lnum, cat, lprops->free,
2201 lprops->dirty);
2202 return -EINVAL;
2203 }
2204 break;
2205 case LPROPS_FREEABLE:
2206 case LPROPS_FRDI_IDX:
2207 if (lprops->free + lprops->dirty != c->leb_size) {
2208 ubifs_err(c, "LEB %d cat %d free %d dirty %d",
2209 lprops->lnum, cat, lprops->free,
2210 lprops->dirty);
2211 return -EINVAL;
2212 }
2213 break;
2214 }
2215 }
2216 return 0;
2217 }
2218
2219 /**
2220 * dbg_check_lpt_nodes - check nnodes and pnodes.
2221 * @c: the UBIFS file-system description object
2222 * @cnode: next cnode (nnode or pnode) to check
2223 * @row: row of cnode (root is zero)
2224 * @col: column of cnode (leftmost is zero)
2225 *
2226 * This function returns %0 on success and a negative error code on failure.
2227 */
dbg_check_lpt_nodes(struct ubifs_info * c,struct ubifs_cnode * cnode,int row,int col)2228 int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
2229 int row, int col)
2230 {
2231 struct ubifs_nnode *nnode, *nn;
2232 struct ubifs_cnode *cn;
2233 int num, iip = 0, err;
2234
2235 if (!dbg_is_chk_lprops(c))
2236 return 0;
2237
2238 while (cnode) {
2239 ubifs_assert(row >= 0);
2240 nnode = cnode->parent;
2241 if (cnode->level) {
2242 /* cnode is a nnode */
2243 num = calc_nnode_num(row, col);
2244 if (cnode->num != num) {
2245 ubifs_err(c, "nnode num %d expected %d parent num %d iip %d",
2246 cnode->num, num,
2247 (nnode ? nnode->num : 0), cnode->iip);
2248 return -EINVAL;
2249 }
2250 nn = (struct ubifs_nnode *)cnode;
2251 while (iip < UBIFS_LPT_FANOUT) {
2252 cn = nn->nbranch[iip].cnode;
2253 if (cn) {
2254 /* Go down */
2255 row += 1;
2256 col <<= UBIFS_LPT_FANOUT_SHIFT;
2257 col += iip;
2258 iip = 0;
2259 cnode = cn;
2260 break;
2261 }
2262 /* Go right */
2263 iip += 1;
2264 }
2265 if (iip < UBIFS_LPT_FANOUT)
2266 continue;
2267 } else {
2268 struct ubifs_pnode *pnode;
2269
2270 /* cnode is a pnode */
2271 pnode = (struct ubifs_pnode *)cnode;
2272 err = dbg_chk_pnode(c, pnode, col);
2273 if (err)
2274 return err;
2275 }
2276 /* Go up and to the right */
2277 row -= 1;
2278 col >>= UBIFS_LPT_FANOUT_SHIFT;
2279 iip = cnode->iip + 1;
2280 cnode = (struct ubifs_cnode *)nnode;
2281 }
2282 return 0;
2283 }
2284