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 <log.h>
37 #include <dm/devres.h>
38 #include <linux/crc16.h>
39 #include <linux/math64.h>
40 #include <linux/slab.h>
41 #else
42 #include <linux/compat.h>
43 #include <linux/err.h>
44 #include <ubi_uboot.h>
45 #include "crc16.h"
46 #endif
47
48 /**
49 * do_calc_lpt_geom - calculate sizes for the LPT area.
50 * @c: the UBIFS file-system description object
51 *
52 * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
53 * properties of the flash and whether LPT is "big" (c->big_lpt).
54 */
do_calc_lpt_geom(struct ubifs_info * c)55 static void do_calc_lpt_geom(struct ubifs_info *c)
56 {
57 int i, n, bits, per_leb_wastage, max_pnode_cnt;
58 long long sz, tot_wastage;
59
60 n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
61 max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
62
63 c->lpt_hght = 1;
64 n = UBIFS_LPT_FANOUT;
65 while (n < max_pnode_cnt) {
66 c->lpt_hght += 1;
67 n <<= UBIFS_LPT_FANOUT_SHIFT;
68 }
69
70 c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
71
72 n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
73 c->nnode_cnt = n;
74 for (i = 1; i < c->lpt_hght; i++) {
75 n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
76 c->nnode_cnt += n;
77 }
78
79 c->space_bits = fls(c->leb_size) - 3;
80 c->lpt_lnum_bits = fls(c->lpt_lebs);
81 c->lpt_offs_bits = fls(c->leb_size - 1);
82 c->lpt_spc_bits = fls(c->leb_size);
83
84 n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
85 c->pcnt_bits = fls(n - 1);
86
87 c->lnum_bits = fls(c->max_leb_cnt - 1);
88
89 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
90 (c->big_lpt ? c->pcnt_bits : 0) +
91 (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
92 c->pnode_sz = (bits + 7) / 8;
93
94 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
95 (c->big_lpt ? c->pcnt_bits : 0) +
96 (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
97 c->nnode_sz = (bits + 7) / 8;
98
99 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
100 c->lpt_lebs * c->lpt_spc_bits * 2;
101 c->ltab_sz = (bits + 7) / 8;
102
103 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
104 c->lnum_bits * c->lsave_cnt;
105 c->lsave_sz = (bits + 7) / 8;
106
107 /* Calculate the minimum LPT size */
108 c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
109 c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
110 c->lpt_sz += c->ltab_sz;
111 if (c->big_lpt)
112 c->lpt_sz += c->lsave_sz;
113
114 /* Add wastage */
115 sz = c->lpt_sz;
116 per_leb_wastage = max_t(int, c->pnode_sz, c->nnode_sz);
117 sz += per_leb_wastage;
118 tot_wastage = per_leb_wastage;
119 while (sz > c->leb_size) {
120 sz += per_leb_wastage;
121 sz -= c->leb_size;
122 tot_wastage += per_leb_wastage;
123 }
124 tot_wastage += ALIGN(sz, c->min_io_size) - sz;
125 c->lpt_sz += tot_wastage;
126 }
127
128 /**
129 * ubifs_calc_lpt_geom - calculate and check sizes for the LPT area.
130 * @c: the UBIFS file-system description object
131 *
132 * This function returns %0 on success and a negative error code on failure.
133 */
ubifs_calc_lpt_geom(struct ubifs_info * c)134 int ubifs_calc_lpt_geom(struct ubifs_info *c)
135 {
136 int lebs_needed;
137 long long sz;
138
139 do_calc_lpt_geom(c);
140
141 /* Verify that lpt_lebs is big enough */
142 sz = c->lpt_sz * 2; /* Must have at least 2 times the size */
143 lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size);
144 if (lebs_needed > c->lpt_lebs) {
145 ubifs_err(c, "too few LPT LEBs");
146 return -EINVAL;
147 }
148
149 /* Verify that ltab fits in a single LEB (since ltab is a single node */
150 if (c->ltab_sz > c->leb_size) {
151 ubifs_err(c, "LPT ltab too big");
152 return -EINVAL;
153 }
154
155 c->check_lpt_free = c->big_lpt;
156 return 0;
157 }
158
159 /**
160 * calc_dflt_lpt_geom - calculate default LPT geometry.
161 * @c: the UBIFS file-system description object
162 * @main_lebs: number of main area LEBs is passed and returned here
163 * @big_lpt: whether the LPT area is "big" is returned here
164 *
165 * The size of the LPT area depends on parameters that themselves are dependent
166 * on the size of the LPT area. This function, successively recalculates the LPT
167 * area geometry until the parameters and resultant geometry are consistent.
168 *
169 * This function returns %0 on success and a negative error code on failure.
170 */
calc_dflt_lpt_geom(struct ubifs_info * c,int * main_lebs,int * big_lpt)171 static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs,
172 int *big_lpt)
173 {
174 int i, lebs_needed;
175 long long sz;
176
177 /* Start by assuming the minimum number of LPT LEBs */
178 c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
179 c->main_lebs = *main_lebs - c->lpt_lebs;
180 if (c->main_lebs <= 0)
181 return -EINVAL;
182
183 /* And assume we will use the small LPT model */
184 c->big_lpt = 0;
185
186 /*
187 * Calculate the geometry based on assumptions above and then see if it
188 * makes sense
189 */
190 do_calc_lpt_geom(c);
191
192 /* Small LPT model must have lpt_sz < leb_size */
193 if (c->lpt_sz > c->leb_size) {
194 /* Nope, so try again using big LPT model */
195 c->big_lpt = 1;
196 do_calc_lpt_geom(c);
197 }
198
199 /* Now check there are enough LPT LEBs */
200 for (i = 0; i < 64 ; i++) {
201 sz = c->lpt_sz * 4; /* Allow 4 times the size */
202 lebs_needed = div_u64(sz + c->leb_size - 1, c->leb_size);
203 if (lebs_needed > c->lpt_lebs) {
204 /* Not enough LPT LEBs so try again with more */
205 c->lpt_lebs = lebs_needed;
206 c->main_lebs = *main_lebs - c->lpt_lebs;
207 if (c->main_lebs <= 0)
208 return -EINVAL;
209 do_calc_lpt_geom(c);
210 continue;
211 }
212 if (c->ltab_sz > c->leb_size) {
213 ubifs_err(c, "LPT ltab too big");
214 return -EINVAL;
215 }
216 *main_lebs = c->main_lebs;
217 *big_lpt = c->big_lpt;
218 return 0;
219 }
220 return -EINVAL;
221 }
222
223 /**
224 * pack_bits - pack bit fields end-to-end.
225 * @addr: address at which to pack (passed and next address returned)
226 * @pos: bit position at which to pack (passed and next position returned)
227 * @val: value to pack
228 * @nrbits: number of bits of value to pack (1-32)
229 */
pack_bits(uint8_t ** addr,int * pos,uint32_t val,int nrbits)230 static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
231 {
232 uint8_t *p = *addr;
233 int b = *pos;
234
235 ubifs_assert(nrbits > 0);
236 ubifs_assert(nrbits <= 32);
237 ubifs_assert(*pos >= 0);
238 ubifs_assert(*pos < 8);
239 ubifs_assert((val >> nrbits) == 0 || nrbits == 32);
240 if (b) {
241 *p |= ((uint8_t)val) << b;
242 nrbits += b;
243 if (nrbits > 8) {
244 *++p = (uint8_t)(val >>= (8 - b));
245 if (nrbits > 16) {
246 *++p = (uint8_t)(val >>= 8);
247 if (nrbits > 24) {
248 *++p = (uint8_t)(val >>= 8);
249 if (nrbits > 32)
250 *++p = (uint8_t)(val >>= 8);
251 }
252 }
253 }
254 } else {
255 *p = (uint8_t)val;
256 if (nrbits > 8) {
257 *++p = (uint8_t)(val >>= 8);
258 if (nrbits > 16) {
259 *++p = (uint8_t)(val >>= 8);
260 if (nrbits > 24)
261 *++p = (uint8_t)(val >>= 8);
262 }
263 }
264 }
265 b = nrbits & 7;
266 if (b == 0)
267 p++;
268 *addr = p;
269 *pos = b;
270 }
271
272 /**
273 * ubifs_unpack_bits - unpack bit fields.
274 * @addr: address at which to unpack (passed and next address returned)
275 * @pos: bit position at which to unpack (passed and next position returned)
276 * @nrbits: number of bits of value to unpack (1-32)
277 *
278 * This functions returns the value unpacked.
279 */
ubifs_unpack_bits(uint8_t ** addr,int * pos,int nrbits)280 uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
281 {
282 const int k = 32 - nrbits;
283 uint8_t *p = *addr;
284 int b = *pos;
285 uint32_t uninitialized_var(val);
286 const int bytes = (nrbits + b + 7) >> 3;
287
288 ubifs_assert(nrbits > 0);
289 ubifs_assert(nrbits <= 32);
290 ubifs_assert(*pos >= 0);
291 ubifs_assert(*pos < 8);
292 if (b) {
293 switch (bytes) {
294 case 2:
295 val = p[1];
296 break;
297 case 3:
298 val = p[1] | ((uint32_t)p[2] << 8);
299 break;
300 case 4:
301 val = p[1] | ((uint32_t)p[2] << 8) |
302 ((uint32_t)p[3] << 16);
303 break;
304 case 5:
305 val = p[1] | ((uint32_t)p[2] << 8) |
306 ((uint32_t)p[3] << 16) |
307 ((uint32_t)p[4] << 24);
308 }
309 val <<= (8 - b);
310 val |= *p >> b;
311 nrbits += b;
312 } else {
313 switch (bytes) {
314 case 1:
315 val = p[0];
316 break;
317 case 2:
318 val = p[0] | ((uint32_t)p[1] << 8);
319 break;
320 case 3:
321 val = p[0] | ((uint32_t)p[1] << 8) |
322 ((uint32_t)p[2] << 16);
323 break;
324 case 4:
325 val = p[0] | ((uint32_t)p[1] << 8) |
326 ((uint32_t)p[2] << 16) |
327 ((uint32_t)p[3] << 24);
328 break;
329 }
330 }
331 val <<= k;
332 val >>= k;
333 b = nrbits & 7;
334 p += nrbits >> 3;
335 *addr = p;
336 *pos = b;
337 ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
338 return val;
339 }
340
341 /**
342 * ubifs_pack_pnode - pack all the bit fields of a pnode.
343 * @c: UBIFS file-system description object
344 * @buf: buffer into which to pack
345 * @pnode: pnode to pack
346 */
ubifs_pack_pnode(struct ubifs_info * c,void * buf,struct ubifs_pnode * pnode)347 void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
348 struct ubifs_pnode *pnode)
349 {
350 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
351 int i, pos = 0;
352 uint16_t crc;
353
354 pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
355 if (c->big_lpt)
356 pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
357 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
358 pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
359 c->space_bits);
360 pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
361 c->space_bits);
362 if (pnode->lprops[i].flags & LPROPS_INDEX)
363 pack_bits(&addr, &pos, 1, 1);
364 else
365 pack_bits(&addr, &pos, 0, 1);
366 }
367 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
368 c->pnode_sz - UBIFS_LPT_CRC_BYTES);
369 addr = buf;
370 pos = 0;
371 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
372 }
373
374 /**
375 * ubifs_pack_nnode - pack all the bit fields of a nnode.
376 * @c: UBIFS file-system description object
377 * @buf: buffer into which to pack
378 * @nnode: nnode to pack
379 */
ubifs_pack_nnode(struct ubifs_info * c,void * buf,struct ubifs_nnode * nnode)380 void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
381 struct ubifs_nnode *nnode)
382 {
383 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
384 int i, pos = 0;
385 uint16_t crc;
386
387 pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
388 if (c->big_lpt)
389 pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
390 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
391 int lnum = nnode->nbranch[i].lnum;
392
393 if (lnum == 0)
394 lnum = c->lpt_last + 1;
395 pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
396 pack_bits(&addr, &pos, nnode->nbranch[i].offs,
397 c->lpt_offs_bits);
398 }
399 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
400 c->nnode_sz - UBIFS_LPT_CRC_BYTES);
401 addr = buf;
402 pos = 0;
403 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
404 }
405
406 /**
407 * ubifs_pack_ltab - pack the LPT's own lprops table.
408 * @c: UBIFS file-system description object
409 * @buf: buffer into which to pack
410 * @ltab: LPT's own lprops table to pack
411 */
ubifs_pack_ltab(struct ubifs_info * c,void * buf,struct ubifs_lpt_lprops * ltab)412 void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
413 struct ubifs_lpt_lprops *ltab)
414 {
415 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
416 int i, pos = 0;
417 uint16_t crc;
418
419 pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
420 for (i = 0; i < c->lpt_lebs; i++) {
421 pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
422 pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
423 }
424 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
425 c->ltab_sz - UBIFS_LPT_CRC_BYTES);
426 addr = buf;
427 pos = 0;
428 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
429 }
430
431 /**
432 * ubifs_pack_lsave - pack the LPT's save table.
433 * @c: UBIFS file-system description object
434 * @buf: buffer into which to pack
435 * @lsave: LPT's save table to pack
436 */
ubifs_pack_lsave(struct ubifs_info * c,void * buf,int * lsave)437 void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
438 {
439 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
440 int i, pos = 0;
441 uint16_t crc;
442
443 pack_bits(&addr, &pos, UBIFS_LPT_LSAVE, UBIFS_LPT_TYPE_BITS);
444 for (i = 0; i < c->lsave_cnt; i++)
445 pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
446 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
447 c->lsave_sz - UBIFS_LPT_CRC_BYTES);
448 addr = buf;
449 pos = 0;
450 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
451 }
452
453 /**
454 * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
455 * @c: UBIFS file-system description object
456 * @lnum: LEB number to which to add dirty space
457 * @dirty: amount of dirty space to add
458 */
ubifs_add_lpt_dirt(struct ubifs_info * c,int lnum,int dirty)459 void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
460 {
461 if (!dirty || !lnum)
462 return;
463 dbg_lp("LEB %d add %d to %d",
464 lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
465 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
466 c->ltab[lnum - c->lpt_first].dirty += dirty;
467 }
468
469 /**
470 * set_ltab - set LPT LEB properties.
471 * @c: UBIFS file-system description object
472 * @lnum: LEB number
473 * @free: amount of free space
474 * @dirty: amount of dirty space
475 */
set_ltab(struct ubifs_info * c,int lnum,int free,int dirty)476 static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
477 {
478 dbg_lp("LEB %d free %d dirty %d to %d %d",
479 lnum, c->ltab[lnum - c->lpt_first].free,
480 c->ltab[lnum - c->lpt_first].dirty, free, dirty);
481 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
482 c->ltab[lnum - c->lpt_first].free = free;
483 c->ltab[lnum - c->lpt_first].dirty = dirty;
484 }
485
486 /**
487 * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
488 * @c: UBIFS file-system description object
489 * @nnode: nnode for which to add dirt
490 */
ubifs_add_nnode_dirt(struct ubifs_info * c,struct ubifs_nnode * nnode)491 void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
492 {
493 struct ubifs_nnode *np = nnode->parent;
494
495 if (np)
496 ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
497 c->nnode_sz);
498 else {
499 ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
500 if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
501 c->lpt_drty_flgs |= LTAB_DIRTY;
502 ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
503 }
504 }
505 }
506
507 /**
508 * add_pnode_dirt - add dirty space to LPT LEB properties.
509 * @c: UBIFS file-system description object
510 * @pnode: pnode for which to add dirt
511 */
add_pnode_dirt(struct ubifs_info * c,struct ubifs_pnode * pnode)512 static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
513 {
514 ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
515 c->pnode_sz);
516 }
517
518 /**
519 * calc_nnode_num - calculate nnode number.
520 * @row: the row in the tree (root is zero)
521 * @col: the column in the row (leftmost is zero)
522 *
523 * The nnode number is a number that uniquely identifies a nnode and can be used
524 * easily to traverse the tree from the root to that nnode.
525 *
526 * This function calculates and returns the nnode number for the nnode at @row
527 * and @col.
528 */
calc_nnode_num(int row,int col)529 static int calc_nnode_num(int row, int col)
530 {
531 int num, bits;
532
533 num = 1;
534 while (row--) {
535 bits = (col & (UBIFS_LPT_FANOUT - 1));
536 col >>= UBIFS_LPT_FANOUT_SHIFT;
537 num <<= UBIFS_LPT_FANOUT_SHIFT;
538 num |= bits;
539 }
540 return num;
541 }
542
543 /**
544 * calc_nnode_num_from_parent - calculate nnode number.
545 * @c: UBIFS file-system description object
546 * @parent: parent nnode
547 * @iip: index in parent
548 *
549 * The nnode number is a number that uniquely identifies a nnode and can be used
550 * easily to traverse the tree from the root to that nnode.
551 *
552 * This function calculates and returns the nnode number based on the parent's
553 * nnode number and the index in parent.
554 */
calc_nnode_num_from_parent(const struct ubifs_info * c,struct ubifs_nnode * parent,int iip)555 static int calc_nnode_num_from_parent(const struct ubifs_info *c,
556 struct ubifs_nnode *parent, int iip)
557 {
558 int num, shft;
559
560 if (!parent)
561 return 1;
562 shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
563 num = parent->num ^ (1 << shft);
564 num |= (UBIFS_LPT_FANOUT + iip) << shft;
565 return num;
566 }
567
568 /**
569 * calc_pnode_num_from_parent - calculate pnode number.
570 * @c: UBIFS file-system description object
571 * @parent: parent nnode
572 * @iip: index in parent
573 *
574 * The pnode number is a number that uniquely identifies a pnode and can be used
575 * easily to traverse the tree from the root to that pnode.
576 *
577 * This function calculates and returns the pnode number based on the parent's
578 * nnode number and the index in parent.
579 */
calc_pnode_num_from_parent(const struct ubifs_info * c,struct ubifs_nnode * parent,int iip)580 static int calc_pnode_num_from_parent(const struct ubifs_info *c,
581 struct ubifs_nnode *parent, int iip)
582 {
583 int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
584
585 for (i = 0; i < n; i++) {
586 num <<= UBIFS_LPT_FANOUT_SHIFT;
587 num |= pnum & (UBIFS_LPT_FANOUT - 1);
588 pnum >>= UBIFS_LPT_FANOUT_SHIFT;
589 }
590 num <<= UBIFS_LPT_FANOUT_SHIFT;
591 num |= iip;
592 return num;
593 }
594
595 /**
596 * ubifs_create_dflt_lpt - create default LPT.
597 * @c: UBIFS file-system description object
598 * @main_lebs: number of main area LEBs is passed and returned here
599 * @lpt_first: LEB number of first LPT LEB
600 * @lpt_lebs: number of LEBs for LPT is passed and returned here
601 * @big_lpt: use big LPT model is passed and returned here
602 *
603 * This function returns %0 on success and a negative error code on failure.
604 */
ubifs_create_dflt_lpt(struct ubifs_info * c,int * main_lebs,int lpt_first,int * lpt_lebs,int * big_lpt)605 int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
606 int *lpt_lebs, int *big_lpt)
607 {
608 int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row;
609 int blnum, boffs, bsz, bcnt;
610 struct ubifs_pnode *pnode = NULL;
611 struct ubifs_nnode *nnode = NULL;
612 void *buf = NULL, *p;
613 struct ubifs_lpt_lprops *ltab = NULL;
614 int *lsave = NULL;
615
616 err = calc_dflt_lpt_geom(c, main_lebs, big_lpt);
617 if (err)
618 return err;
619 *lpt_lebs = c->lpt_lebs;
620
621 /* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */
622 c->lpt_first = lpt_first;
623 /* Needed by 'set_ltab()' */
624 c->lpt_last = lpt_first + c->lpt_lebs - 1;
625 /* Needed by 'ubifs_pack_lsave()' */
626 c->main_first = c->leb_cnt - *main_lebs;
627
628 lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
629 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
630 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
631 buf = vmalloc(c->leb_size);
632 ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
633 if (!pnode || !nnode || !buf || !ltab || !lsave) {
634 err = -ENOMEM;
635 goto out;
636 }
637
638 ubifs_assert(!c->ltab);
639 c->ltab = ltab; /* Needed by set_ltab */
640
641 /* Initialize LPT's own lprops */
642 for (i = 0; i < c->lpt_lebs; i++) {
643 ltab[i].free = c->leb_size;
644 ltab[i].dirty = 0;
645 ltab[i].tgc = 0;
646 ltab[i].cmt = 0;
647 }
648
649 lnum = lpt_first;
650 p = buf;
651 /* Number of leaf nodes (pnodes) */
652 cnt = c->pnode_cnt;
653
654 /*
655 * The first pnode contains the LEB properties for the LEBs that contain
656 * the root inode node and the root index node of the index tree.
657 */
658 node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8);
659 iopos = ALIGN(node_sz, c->min_io_size);
660 pnode->lprops[0].free = c->leb_size - iopos;
661 pnode->lprops[0].dirty = iopos - node_sz;
662 pnode->lprops[0].flags = LPROPS_INDEX;
663
664 node_sz = UBIFS_INO_NODE_SZ;
665 iopos = ALIGN(node_sz, c->min_io_size);
666 pnode->lprops[1].free = c->leb_size - iopos;
667 pnode->lprops[1].dirty = iopos - node_sz;
668
669 for (i = 2; i < UBIFS_LPT_FANOUT; i++)
670 pnode->lprops[i].free = c->leb_size;
671
672 /* Add first pnode */
673 ubifs_pack_pnode(c, p, pnode);
674 p += c->pnode_sz;
675 len = c->pnode_sz;
676 pnode->num += 1;
677
678 /* Reset pnode values for remaining pnodes */
679 pnode->lprops[0].free = c->leb_size;
680 pnode->lprops[0].dirty = 0;
681 pnode->lprops[0].flags = 0;
682
683 pnode->lprops[1].free = c->leb_size;
684 pnode->lprops[1].dirty = 0;
685
686 /*
687 * To calculate the internal node branches, we keep information about
688 * the level below.
689 */
690 blnum = lnum; /* LEB number of level below */
691 boffs = 0; /* Offset of level below */
692 bcnt = cnt; /* Number of nodes in level below */
693 bsz = c->pnode_sz; /* Size of nodes in level below */
694
695 /* Add all remaining pnodes */
696 for (i = 1; i < cnt; i++) {
697 if (len + c->pnode_sz > c->leb_size) {
698 alen = ALIGN(len, c->min_io_size);
699 set_ltab(c, lnum, c->leb_size - alen, alen - len);
700 memset(p, 0xff, alen - len);
701 err = ubifs_leb_change(c, lnum++, buf, alen);
702 if (err)
703 goto out;
704 p = buf;
705 len = 0;
706 }
707 ubifs_pack_pnode(c, p, pnode);
708 p += c->pnode_sz;
709 len += c->pnode_sz;
710 /*
711 * pnodes are simply numbered left to right starting at zero,
712 * which means the pnode number can be used easily to traverse
713 * down the tree to the corresponding pnode.
714 */
715 pnode->num += 1;
716 }
717
718 row = 0;
719 for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT)
720 row += 1;
721 /* Add all nnodes, one level at a time */
722 while (1) {
723 /* Number of internal nodes (nnodes) at next level */
724 cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT);
725 for (i = 0; i < cnt; i++) {
726 if (len + c->nnode_sz > c->leb_size) {
727 alen = ALIGN(len, c->min_io_size);
728 set_ltab(c, lnum, c->leb_size - alen,
729 alen - len);
730 memset(p, 0xff, alen - len);
731 err = ubifs_leb_change(c, lnum++, buf, alen);
732 if (err)
733 goto out;
734 p = buf;
735 len = 0;
736 }
737 /* Only 1 nnode at this level, so it is the root */
738 if (cnt == 1) {
739 c->lpt_lnum = lnum;
740 c->lpt_offs = len;
741 }
742 /* Set branches to the level below */
743 for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
744 if (bcnt) {
745 if (boffs + bsz > c->leb_size) {
746 blnum += 1;
747 boffs = 0;
748 }
749 nnode->nbranch[j].lnum = blnum;
750 nnode->nbranch[j].offs = boffs;
751 boffs += bsz;
752 bcnt--;
753 } else {
754 nnode->nbranch[j].lnum = 0;
755 nnode->nbranch[j].offs = 0;
756 }
757 }
758 nnode->num = calc_nnode_num(row, i);
759 ubifs_pack_nnode(c, p, nnode);
760 p += c->nnode_sz;
761 len += c->nnode_sz;
762 }
763 /* Only 1 nnode at this level, so it is the root */
764 if (cnt == 1)
765 break;
766 /* Update the information about the level below */
767 bcnt = cnt;
768 bsz = c->nnode_sz;
769 row -= 1;
770 }
771
772 if (*big_lpt) {
773 /* Need to add LPT's save table */
774 if (len + c->lsave_sz > c->leb_size) {
775 alen = ALIGN(len, c->min_io_size);
776 set_ltab(c, lnum, c->leb_size - alen, alen - len);
777 memset(p, 0xff, alen - len);
778 err = ubifs_leb_change(c, lnum++, buf, alen);
779 if (err)
780 goto out;
781 p = buf;
782 len = 0;
783 }
784
785 c->lsave_lnum = lnum;
786 c->lsave_offs = len;
787
788 for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++)
789 lsave[i] = c->main_first + i;
790 for (; i < c->lsave_cnt; i++)
791 lsave[i] = c->main_first;
792
793 ubifs_pack_lsave(c, p, lsave);
794 p += c->lsave_sz;
795 len += c->lsave_sz;
796 }
797
798 /* Need to add LPT's own LEB properties table */
799 if (len + c->ltab_sz > c->leb_size) {
800 alen = ALIGN(len, c->min_io_size);
801 set_ltab(c, lnum, c->leb_size - alen, alen - len);
802 memset(p, 0xff, alen - len);
803 err = ubifs_leb_change(c, lnum++, buf, alen);
804 if (err)
805 goto out;
806 p = buf;
807 len = 0;
808 }
809
810 c->ltab_lnum = lnum;
811 c->ltab_offs = len;
812
813 /* Update ltab before packing it */
814 len += c->ltab_sz;
815 alen = ALIGN(len, c->min_io_size);
816 set_ltab(c, lnum, c->leb_size - alen, alen - len);
817
818 ubifs_pack_ltab(c, p, ltab);
819 p += c->ltab_sz;
820
821 /* Write remaining buffer */
822 memset(p, 0xff, alen - len);
823 err = ubifs_leb_change(c, lnum, buf, alen);
824 if (err)
825 goto out;
826
827 c->nhead_lnum = lnum;
828 c->nhead_offs = ALIGN(len, c->min_io_size);
829
830 dbg_lp("space_bits %d", c->space_bits);
831 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
832 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
833 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
834 dbg_lp("pcnt_bits %d", c->pcnt_bits);
835 dbg_lp("lnum_bits %d", c->lnum_bits);
836 dbg_lp("pnode_sz %d", c->pnode_sz);
837 dbg_lp("nnode_sz %d", c->nnode_sz);
838 dbg_lp("ltab_sz %d", c->ltab_sz);
839 dbg_lp("lsave_sz %d", c->lsave_sz);
840 dbg_lp("lsave_cnt %d", c->lsave_cnt);
841 dbg_lp("lpt_hght %d", c->lpt_hght);
842 dbg_lp("big_lpt %d", c->big_lpt);
843 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
844 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
845 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
846 if (c->big_lpt)
847 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
848 out:
849 c->ltab = NULL;
850 kfree(lsave);
851 vfree(ltab);
852 vfree(buf);
853 kfree(nnode);
854 kfree(pnode);
855 return err;
856 }
857
858 /**
859 * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
860 * @c: UBIFS file-system description object
861 * @pnode: pnode
862 *
863 * When a pnode is loaded into memory, the LEB properties it contains are added,
864 * by this function, to the LEB category lists and heaps.
865 */
update_cats(struct ubifs_info * c,struct ubifs_pnode * pnode)866 static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
867 {
868 int i;
869
870 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
871 int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
872 int lnum = pnode->lprops[i].lnum;
873
874 if (!lnum)
875 return;
876 ubifs_add_to_cat(c, &pnode->lprops[i], cat);
877 }
878 }
879
880 /**
881 * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
882 * @c: UBIFS file-system description object
883 * @old_pnode: pnode copied
884 * @new_pnode: pnode copy
885 *
886 * During commit it is sometimes necessary to copy a pnode
887 * (see dirty_cow_pnode). When that happens, references in
888 * category lists and heaps must be replaced. This function does that.
889 */
replace_cats(struct ubifs_info * c,struct ubifs_pnode * old_pnode,struct ubifs_pnode * new_pnode)890 static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
891 struct ubifs_pnode *new_pnode)
892 {
893 int i;
894
895 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
896 if (!new_pnode->lprops[i].lnum)
897 return;
898 ubifs_replace_cat(c, &old_pnode->lprops[i],
899 &new_pnode->lprops[i]);
900 }
901 }
902
903 /**
904 * check_lpt_crc - check LPT node crc is correct.
905 * @c: UBIFS file-system description object
906 * @buf: buffer containing node
907 * @len: length of node
908 *
909 * This function returns %0 on success and a negative error code on failure.
910 */
check_lpt_crc(const struct ubifs_info * c,void * buf,int len)911 static int check_lpt_crc(const struct ubifs_info *c, void *buf, int len)
912 {
913 int pos = 0;
914 uint8_t *addr = buf;
915 uint16_t crc, calc_crc;
916
917 crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
918 calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
919 len - UBIFS_LPT_CRC_BYTES);
920 if (crc != calc_crc) {
921 ubifs_err(c, "invalid crc in LPT node: crc %hx calc %hx",
922 crc, calc_crc);
923 dump_stack();
924 return -EINVAL;
925 }
926 return 0;
927 }
928
929 /**
930 * check_lpt_type - check LPT node type is correct.
931 * @c: UBIFS file-system description object
932 * @addr: address of type bit field is passed and returned updated here
933 * @pos: position of type bit field is passed and returned updated here
934 * @type: expected type
935 *
936 * This function returns %0 on success and a negative error code on failure.
937 */
check_lpt_type(const struct ubifs_info * c,uint8_t ** addr,int * pos,int type)938 static int check_lpt_type(const struct ubifs_info *c, uint8_t **addr,
939 int *pos, int type)
940 {
941 int node_type;
942
943 node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
944 if (node_type != type) {
945 ubifs_err(c, "invalid type (%d) in LPT node type %d",
946 node_type, type);
947 dump_stack();
948 return -EINVAL;
949 }
950 return 0;
951 }
952
953 /**
954 * unpack_pnode - unpack a pnode.
955 * @c: UBIFS file-system description object
956 * @buf: buffer containing packed pnode to unpack
957 * @pnode: pnode structure to fill
958 *
959 * This function returns %0 on success and a negative error code on failure.
960 */
unpack_pnode(const struct ubifs_info * c,void * buf,struct ubifs_pnode * pnode)961 static int unpack_pnode(const struct ubifs_info *c, void *buf,
962 struct ubifs_pnode *pnode)
963 {
964 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
965 int i, pos = 0, err;
966
967 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_PNODE);
968 if (err)
969 return err;
970 if (c->big_lpt)
971 pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
972 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
973 struct ubifs_lprops * const lprops = &pnode->lprops[i];
974
975 lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
976 lprops->free <<= 3;
977 lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
978 lprops->dirty <<= 3;
979
980 if (ubifs_unpack_bits(&addr, &pos, 1))
981 lprops->flags = LPROPS_INDEX;
982 else
983 lprops->flags = 0;
984 lprops->flags |= ubifs_categorize_lprops(c, lprops);
985 }
986 err = check_lpt_crc(c, buf, c->pnode_sz);
987 return err;
988 }
989
990 /**
991 * ubifs_unpack_nnode - unpack a nnode.
992 * @c: UBIFS file-system description object
993 * @buf: buffer containing packed nnode to unpack
994 * @nnode: nnode structure to fill
995 *
996 * This function returns %0 on success and a negative error code on failure.
997 */
ubifs_unpack_nnode(const struct ubifs_info * c,void * buf,struct ubifs_nnode * nnode)998 int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
999 struct ubifs_nnode *nnode)
1000 {
1001 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1002 int i, pos = 0, err;
1003
1004 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_NNODE);
1005 if (err)
1006 return err;
1007 if (c->big_lpt)
1008 nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
1009 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1010 int lnum;
1011
1012 lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
1013 c->lpt_first;
1014 if (lnum == c->lpt_last + 1)
1015 lnum = 0;
1016 nnode->nbranch[i].lnum = lnum;
1017 nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
1018 c->lpt_offs_bits);
1019 }
1020 err = check_lpt_crc(c, buf, c->nnode_sz);
1021 return err;
1022 }
1023
1024 /**
1025 * unpack_ltab - unpack the LPT's own lprops table.
1026 * @c: UBIFS file-system description object
1027 * @buf: buffer from which to unpack
1028 *
1029 * This function returns %0 on success and a negative error code on failure.
1030 */
unpack_ltab(const struct ubifs_info * c,void * buf)1031 static int unpack_ltab(const struct ubifs_info *c, void *buf)
1032 {
1033 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1034 int i, pos = 0, err;
1035
1036 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LTAB);
1037 if (err)
1038 return err;
1039 for (i = 0; i < c->lpt_lebs; i++) {
1040 int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1041 int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1042
1043 if (free < 0 || free > c->leb_size || dirty < 0 ||
1044 dirty > c->leb_size || free + dirty > c->leb_size)
1045 return -EINVAL;
1046
1047 c->ltab[i].free = free;
1048 c->ltab[i].dirty = dirty;
1049 c->ltab[i].tgc = 0;
1050 c->ltab[i].cmt = 0;
1051 }
1052 err = check_lpt_crc(c, buf, c->ltab_sz);
1053 return err;
1054 }
1055
1056 #ifndef __UBOOT__
1057 /**
1058 * unpack_lsave - unpack the LPT's save table.
1059 * @c: UBIFS file-system description object
1060 * @buf: buffer from which to unpack
1061 *
1062 * This function returns %0 on success and a negative error code on failure.
1063 */
unpack_lsave(const struct ubifs_info * c,void * buf)1064 static int unpack_lsave(const struct ubifs_info *c, void *buf)
1065 {
1066 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1067 int i, pos = 0, err;
1068
1069 err = check_lpt_type(c, &addr, &pos, UBIFS_LPT_LSAVE);
1070 if (err)
1071 return err;
1072 for (i = 0; i < c->lsave_cnt; i++) {
1073 int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits);
1074
1075 if (lnum < c->main_first || lnum >= c->leb_cnt)
1076 return -EINVAL;
1077 c->lsave[i] = lnum;
1078 }
1079 err = check_lpt_crc(c, buf, c->lsave_sz);
1080 return err;
1081 }
1082 #endif
1083
1084 /**
1085 * validate_nnode - validate a nnode.
1086 * @c: UBIFS file-system description object
1087 * @nnode: nnode to validate
1088 * @parent: parent nnode (or NULL for the root nnode)
1089 * @iip: index in parent
1090 *
1091 * This function returns %0 on success and a negative error code on failure.
1092 */
validate_nnode(const struct ubifs_info * c,struct ubifs_nnode * nnode,struct ubifs_nnode * parent,int iip)1093 static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode,
1094 struct ubifs_nnode *parent, int iip)
1095 {
1096 int i, lvl, max_offs;
1097
1098 if (c->big_lpt) {
1099 int num = calc_nnode_num_from_parent(c, parent, iip);
1100
1101 if (nnode->num != num)
1102 return -EINVAL;
1103 }
1104 lvl = parent ? parent->level - 1 : c->lpt_hght;
1105 if (lvl < 1)
1106 return -EINVAL;
1107 if (lvl == 1)
1108 max_offs = c->leb_size - c->pnode_sz;
1109 else
1110 max_offs = c->leb_size - c->nnode_sz;
1111 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1112 int lnum = nnode->nbranch[i].lnum;
1113 int offs = nnode->nbranch[i].offs;
1114
1115 if (lnum == 0) {
1116 if (offs != 0)
1117 return -EINVAL;
1118 continue;
1119 }
1120 if (lnum < c->lpt_first || lnum > c->lpt_last)
1121 return -EINVAL;
1122 if (offs < 0 || offs > max_offs)
1123 return -EINVAL;
1124 }
1125 return 0;
1126 }
1127
1128 /**
1129 * validate_pnode - validate a pnode.
1130 * @c: UBIFS file-system description object
1131 * @pnode: pnode to validate
1132 * @parent: parent nnode
1133 * @iip: index in parent
1134 *
1135 * This function returns %0 on success and a negative error code on failure.
1136 */
validate_pnode(const struct ubifs_info * c,struct ubifs_pnode * pnode,struct ubifs_nnode * parent,int iip)1137 static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode,
1138 struct ubifs_nnode *parent, int iip)
1139 {
1140 int i;
1141
1142 if (c->big_lpt) {
1143 int num = calc_pnode_num_from_parent(c, parent, iip);
1144
1145 if (pnode->num != num)
1146 return -EINVAL;
1147 }
1148 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1149 int free = pnode->lprops[i].free;
1150 int dirty = pnode->lprops[i].dirty;
1151
1152 if (free < 0 || free > c->leb_size || free % c->min_io_size ||
1153 (free & 7))
1154 return -EINVAL;
1155 if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
1156 return -EINVAL;
1157 if (dirty + free > c->leb_size)
1158 return -EINVAL;
1159 }
1160 return 0;
1161 }
1162
1163 /**
1164 * set_pnode_lnum - set LEB numbers on a pnode.
1165 * @c: UBIFS file-system description object
1166 * @pnode: pnode to update
1167 *
1168 * This function calculates the LEB numbers for the LEB properties it contains
1169 * based on the pnode number.
1170 */
set_pnode_lnum(const struct ubifs_info * c,struct ubifs_pnode * pnode)1171 static void set_pnode_lnum(const struct ubifs_info *c,
1172 struct ubifs_pnode *pnode)
1173 {
1174 int i, lnum;
1175
1176 lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
1177 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1178 if (lnum >= c->leb_cnt)
1179 return;
1180 pnode->lprops[i].lnum = lnum++;
1181 }
1182 }
1183
1184 /**
1185 * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
1186 * @c: UBIFS file-system description object
1187 * @parent: parent nnode (or NULL for the root)
1188 * @iip: index in parent
1189 *
1190 * This function returns %0 on success and a negative error code on failure.
1191 */
ubifs_read_nnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1192 int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1193 {
1194 struct ubifs_nbranch *branch = NULL;
1195 struct ubifs_nnode *nnode = NULL;
1196 void *buf = c->lpt_nod_buf;
1197 int err, lnum, offs;
1198
1199 if (parent) {
1200 branch = &parent->nbranch[iip];
1201 lnum = branch->lnum;
1202 offs = branch->offs;
1203 } else {
1204 lnum = c->lpt_lnum;
1205 offs = c->lpt_offs;
1206 }
1207 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1208 if (!nnode) {
1209 err = -ENOMEM;
1210 goto out;
1211 }
1212 if (lnum == 0) {
1213 /*
1214 * This nnode was not written which just means that the LEB
1215 * properties in the subtree below it describe empty LEBs. We
1216 * make the nnode as though we had read it, which in fact means
1217 * doing almost nothing.
1218 */
1219 if (c->big_lpt)
1220 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1221 } else {
1222 err = ubifs_leb_read(c, lnum, buf, offs, c->nnode_sz, 1);
1223 if (err)
1224 goto out;
1225 err = ubifs_unpack_nnode(c, buf, nnode);
1226 if (err)
1227 goto out;
1228 }
1229 err = validate_nnode(c, nnode, parent, iip);
1230 if (err)
1231 goto out;
1232 if (!c->big_lpt)
1233 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1234 if (parent) {
1235 branch->nnode = nnode;
1236 nnode->level = parent->level - 1;
1237 } else {
1238 c->nroot = nnode;
1239 nnode->level = c->lpt_hght;
1240 }
1241 nnode->parent = parent;
1242 nnode->iip = iip;
1243 return 0;
1244
1245 out:
1246 ubifs_err(c, "error %d reading nnode at %d:%d", err, lnum, offs);
1247 dump_stack();
1248 kfree(nnode);
1249 return err;
1250 }
1251
1252 /**
1253 * read_pnode - read a pnode from flash and link it to the tree in memory.
1254 * @c: UBIFS file-system description object
1255 * @parent: parent nnode
1256 * @iip: index in parent
1257 *
1258 * This function returns %0 on success and a negative error code on failure.
1259 */
read_pnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1260 static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1261 {
1262 struct ubifs_nbranch *branch;
1263 struct ubifs_pnode *pnode = NULL;
1264 void *buf = c->lpt_nod_buf;
1265 int err, lnum, offs;
1266
1267 branch = &parent->nbranch[iip];
1268 lnum = branch->lnum;
1269 offs = branch->offs;
1270 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1271 if (!pnode)
1272 return -ENOMEM;
1273
1274 if (lnum == 0) {
1275 /*
1276 * This pnode was not written which just means that the LEB
1277 * properties in it describe empty LEBs. We make the pnode as
1278 * though we had read it.
1279 */
1280 int i;
1281
1282 if (c->big_lpt)
1283 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1284 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1285 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1286
1287 lprops->free = c->leb_size;
1288 lprops->flags = ubifs_categorize_lprops(c, lprops);
1289 }
1290 } else {
1291 err = ubifs_leb_read(c, lnum, buf, offs, c->pnode_sz, 1);
1292 if (err)
1293 goto out;
1294 err = unpack_pnode(c, buf, pnode);
1295 if (err)
1296 goto out;
1297 }
1298 err = validate_pnode(c, pnode, parent, iip);
1299 if (err)
1300 goto out;
1301 if (!c->big_lpt)
1302 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1303 branch->pnode = pnode;
1304 pnode->parent = parent;
1305 pnode->iip = iip;
1306 set_pnode_lnum(c, pnode);
1307 c->pnodes_have += 1;
1308 return 0;
1309
1310 out:
1311 ubifs_err(c, "error %d reading pnode at %d:%d", err, lnum, offs);
1312 ubifs_dump_pnode(c, pnode, parent, iip);
1313 dump_stack();
1314 ubifs_err(c, "calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
1315 kfree(pnode);
1316 return err;
1317 }
1318
1319 /**
1320 * read_ltab - read LPT's own lprops table.
1321 * @c: UBIFS file-system description object
1322 *
1323 * This function returns %0 on success and a negative error code on failure.
1324 */
read_ltab(struct ubifs_info * c)1325 static int read_ltab(struct ubifs_info *c)
1326 {
1327 int err;
1328 void *buf;
1329
1330 buf = vmalloc(c->ltab_sz);
1331 if (!buf)
1332 return -ENOMEM;
1333 err = ubifs_leb_read(c, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz, 1);
1334 if (err)
1335 goto out;
1336 err = unpack_ltab(c, buf);
1337 out:
1338 vfree(buf);
1339 return err;
1340 }
1341
1342 #ifndef __UBOOT__
1343 /**
1344 * read_lsave - read LPT's save table.
1345 * @c: UBIFS file-system description object
1346 *
1347 * This function returns %0 on success and a negative error code on failure.
1348 */
read_lsave(struct ubifs_info * c)1349 static int read_lsave(struct ubifs_info *c)
1350 {
1351 int err, i;
1352 void *buf;
1353
1354 buf = vmalloc(c->lsave_sz);
1355 if (!buf)
1356 return -ENOMEM;
1357 err = ubifs_leb_read(c, c->lsave_lnum, buf, c->lsave_offs,
1358 c->lsave_sz, 1);
1359 if (err)
1360 goto out;
1361 err = unpack_lsave(c, buf);
1362 if (err)
1363 goto out;
1364 for (i = 0; i < c->lsave_cnt; i++) {
1365 int lnum = c->lsave[i];
1366 struct ubifs_lprops *lprops;
1367
1368 /*
1369 * Due to automatic resizing, the values in the lsave table
1370 * could be beyond the volume size - just ignore them.
1371 */
1372 if (lnum >= c->leb_cnt)
1373 continue;
1374 lprops = ubifs_lpt_lookup(c, lnum);
1375 if (IS_ERR(lprops)) {
1376 err = PTR_ERR(lprops);
1377 goto out;
1378 }
1379 }
1380 out:
1381 vfree(buf);
1382 return err;
1383 }
1384 #endif
1385
1386 /**
1387 * ubifs_get_nnode - get a nnode.
1388 * @c: UBIFS file-system description object
1389 * @parent: parent nnode (or NULL for the root)
1390 * @iip: index in parent
1391 *
1392 * This function returns a pointer to the nnode on success or a negative error
1393 * code on failure.
1394 */
ubifs_get_nnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1395 struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
1396 struct ubifs_nnode *parent, int iip)
1397 {
1398 struct ubifs_nbranch *branch;
1399 struct ubifs_nnode *nnode;
1400 int err;
1401
1402 branch = &parent->nbranch[iip];
1403 nnode = branch->nnode;
1404 if (nnode)
1405 return nnode;
1406 err = ubifs_read_nnode(c, parent, iip);
1407 if (err)
1408 return ERR_PTR(err);
1409 return branch->nnode;
1410 }
1411
1412 /**
1413 * ubifs_get_pnode - get a pnode.
1414 * @c: UBIFS file-system description object
1415 * @parent: parent nnode
1416 * @iip: index in parent
1417 *
1418 * This function returns a pointer to the pnode on success or a negative error
1419 * code on failure.
1420 */
ubifs_get_pnode(struct ubifs_info * c,struct ubifs_nnode * parent,int iip)1421 struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
1422 struct ubifs_nnode *parent, int iip)
1423 {
1424 struct ubifs_nbranch *branch;
1425 struct ubifs_pnode *pnode;
1426 int err;
1427
1428 branch = &parent->nbranch[iip];
1429 pnode = branch->pnode;
1430 if (pnode)
1431 return pnode;
1432 err = read_pnode(c, parent, iip);
1433 if (err)
1434 return ERR_PTR(err);
1435 update_cats(c, branch->pnode);
1436 return branch->pnode;
1437 }
1438
1439 /**
1440 * ubifs_lpt_lookup - lookup LEB properties in the LPT.
1441 * @c: UBIFS file-system description object
1442 * @lnum: LEB number to lookup
1443 *
1444 * This function returns a pointer to the LEB properties on success or a
1445 * negative error code on failure.
1446 */
ubifs_lpt_lookup(struct ubifs_info * c,int lnum)1447 struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
1448 {
1449 int err, i, h, iip, shft;
1450 struct ubifs_nnode *nnode;
1451 struct ubifs_pnode *pnode;
1452
1453 if (!c->nroot) {
1454 err = ubifs_read_nnode(c, NULL, 0);
1455 if (err)
1456 return ERR_PTR(err);
1457 }
1458 nnode = c->nroot;
1459 i = lnum - c->main_first;
1460 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1461 for (h = 1; h < c->lpt_hght; h++) {
1462 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1463 shft -= UBIFS_LPT_FANOUT_SHIFT;
1464 nnode = ubifs_get_nnode(c, nnode, iip);
1465 if (IS_ERR(nnode))
1466 return ERR_CAST(nnode);
1467 }
1468 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1469 pnode = ubifs_get_pnode(c, nnode, iip);
1470 if (IS_ERR(pnode))
1471 return ERR_CAST(pnode);
1472 iip = (i & (UBIFS_LPT_FANOUT - 1));
1473 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1474 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1475 pnode->lprops[iip].flags);
1476 return &pnode->lprops[iip];
1477 }
1478
1479 /**
1480 * dirty_cow_nnode - ensure a nnode is not being committed.
1481 * @c: UBIFS file-system description object
1482 * @nnode: nnode to check
1483 *
1484 * Returns dirtied nnode on success or negative error code on failure.
1485 */
dirty_cow_nnode(struct ubifs_info * c,struct ubifs_nnode * nnode)1486 static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
1487 struct ubifs_nnode *nnode)
1488 {
1489 struct ubifs_nnode *n;
1490 int i;
1491
1492 if (!test_bit(COW_CNODE, &nnode->flags)) {
1493 /* nnode is not being committed */
1494 if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
1495 c->dirty_nn_cnt += 1;
1496 ubifs_add_nnode_dirt(c, nnode);
1497 }
1498 return nnode;
1499 }
1500
1501 /* nnode is being committed, so copy it */
1502 n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1503 if (unlikely(!n))
1504 return ERR_PTR(-ENOMEM);
1505
1506 memcpy(n, nnode, sizeof(struct ubifs_nnode));
1507 n->cnext = NULL;
1508 __set_bit(DIRTY_CNODE, &n->flags);
1509 __clear_bit(COW_CNODE, &n->flags);
1510
1511 /* The children now have new parent */
1512 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1513 struct ubifs_nbranch *branch = &n->nbranch[i];
1514
1515 if (branch->cnode)
1516 branch->cnode->parent = n;
1517 }
1518
1519 ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
1520 __set_bit(OBSOLETE_CNODE, &nnode->flags);
1521
1522 c->dirty_nn_cnt += 1;
1523 ubifs_add_nnode_dirt(c, nnode);
1524 if (nnode->parent)
1525 nnode->parent->nbranch[n->iip].nnode = n;
1526 else
1527 c->nroot = n;
1528 return n;
1529 }
1530
1531 /**
1532 * dirty_cow_pnode - ensure a pnode is not being committed.
1533 * @c: UBIFS file-system description object
1534 * @pnode: pnode to check
1535 *
1536 * Returns dirtied pnode on success or negative error code on failure.
1537 */
dirty_cow_pnode(struct ubifs_info * c,struct ubifs_pnode * pnode)1538 static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
1539 struct ubifs_pnode *pnode)
1540 {
1541 struct ubifs_pnode *p;
1542
1543 if (!test_bit(COW_CNODE, &pnode->flags)) {
1544 /* pnode is not being committed */
1545 if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
1546 c->dirty_pn_cnt += 1;
1547 add_pnode_dirt(c, pnode);
1548 }
1549 return pnode;
1550 }
1551
1552 /* pnode is being committed, so copy it */
1553 p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1554 if (unlikely(!p))
1555 return ERR_PTR(-ENOMEM);
1556
1557 memcpy(p, pnode, sizeof(struct ubifs_pnode));
1558 p->cnext = NULL;
1559 __set_bit(DIRTY_CNODE, &p->flags);
1560 __clear_bit(COW_CNODE, &p->flags);
1561 replace_cats(c, pnode, p);
1562
1563 ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
1564 __set_bit(OBSOLETE_CNODE, &pnode->flags);
1565
1566 c->dirty_pn_cnt += 1;
1567 add_pnode_dirt(c, pnode);
1568 pnode->parent->nbranch[p->iip].pnode = p;
1569 return p;
1570 }
1571
1572 /**
1573 * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
1574 * @c: UBIFS file-system description object
1575 * @lnum: LEB number to lookup
1576 *
1577 * This function returns a pointer to the LEB properties on success or a
1578 * negative error code on failure.
1579 */
ubifs_lpt_lookup_dirty(struct ubifs_info * c,int lnum)1580 struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
1581 {
1582 int err, i, h, iip, shft;
1583 struct ubifs_nnode *nnode;
1584 struct ubifs_pnode *pnode;
1585
1586 if (!c->nroot) {
1587 err = ubifs_read_nnode(c, NULL, 0);
1588 if (err)
1589 return ERR_PTR(err);
1590 }
1591 nnode = c->nroot;
1592 nnode = dirty_cow_nnode(c, nnode);
1593 if (IS_ERR(nnode))
1594 return ERR_CAST(nnode);
1595 i = lnum - c->main_first;
1596 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1597 for (h = 1; h < c->lpt_hght; h++) {
1598 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1599 shft -= UBIFS_LPT_FANOUT_SHIFT;
1600 nnode = ubifs_get_nnode(c, nnode, iip);
1601 if (IS_ERR(nnode))
1602 return ERR_CAST(nnode);
1603 nnode = dirty_cow_nnode(c, nnode);
1604 if (IS_ERR(nnode))
1605 return ERR_CAST(nnode);
1606 }
1607 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1608 pnode = ubifs_get_pnode(c, nnode, iip);
1609 if (IS_ERR(pnode))
1610 return ERR_CAST(pnode);
1611 pnode = dirty_cow_pnode(c, pnode);
1612 if (IS_ERR(pnode))
1613 return ERR_CAST(pnode);
1614 iip = (i & (UBIFS_LPT_FANOUT - 1));
1615 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1616 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1617 pnode->lprops[iip].flags);
1618 ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
1619 return &pnode->lprops[iip];
1620 }
1621
1622 /**
1623 * lpt_init_rd - initialize the LPT for reading.
1624 * @c: UBIFS file-system description object
1625 *
1626 * This function returns %0 on success and a negative error code on failure.
1627 */
lpt_init_rd(struct ubifs_info * c)1628 static int lpt_init_rd(struct ubifs_info *c)
1629 {
1630 int err, i;
1631
1632 c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1633 if (!c->ltab)
1634 return -ENOMEM;
1635
1636 i = max_t(int, c->nnode_sz, c->pnode_sz);
1637 c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
1638 if (!c->lpt_nod_buf)
1639 return -ENOMEM;
1640
1641 for (i = 0; i < LPROPS_HEAP_CNT; i++) {
1642 c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
1643 GFP_KERNEL);
1644 if (!c->lpt_heap[i].arr)
1645 return -ENOMEM;
1646 c->lpt_heap[i].cnt = 0;
1647 c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
1648 }
1649
1650 c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
1651 if (!c->dirty_idx.arr)
1652 return -ENOMEM;
1653 c->dirty_idx.cnt = 0;
1654 c->dirty_idx.max_cnt = LPT_HEAP_SZ;
1655
1656 err = read_ltab(c);
1657 if (err)
1658 return err;
1659
1660 dbg_lp("space_bits %d", c->space_bits);
1661 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
1662 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
1663 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
1664 dbg_lp("pcnt_bits %d", c->pcnt_bits);
1665 dbg_lp("lnum_bits %d", c->lnum_bits);
1666 dbg_lp("pnode_sz %d", c->pnode_sz);
1667 dbg_lp("nnode_sz %d", c->nnode_sz);
1668 dbg_lp("ltab_sz %d", c->ltab_sz);
1669 dbg_lp("lsave_sz %d", c->lsave_sz);
1670 dbg_lp("lsave_cnt %d", c->lsave_cnt);
1671 dbg_lp("lpt_hght %d", c->lpt_hght);
1672 dbg_lp("big_lpt %d", c->big_lpt);
1673 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
1674 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
1675 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
1676 if (c->big_lpt)
1677 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
1678
1679 return 0;
1680 }
1681
1682 #ifndef __UBOOT__
1683 /**
1684 * lpt_init_wr - initialize the LPT for writing.
1685 * @c: UBIFS file-system description object
1686 *
1687 * 'lpt_init_rd()' must have been called already.
1688 *
1689 * This function returns %0 on success and a negative error code on failure.
1690 */
lpt_init_wr(struct ubifs_info * c)1691 static int lpt_init_wr(struct ubifs_info *c)
1692 {
1693 int err, i;
1694
1695 c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1696 if (!c->ltab_cmt)
1697 return -ENOMEM;
1698
1699 c->lpt_buf = vmalloc(c->leb_size);
1700 if (!c->lpt_buf)
1701 return -ENOMEM;
1702
1703 if (c->big_lpt) {
1704 c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
1705 if (!c->lsave)
1706 return -ENOMEM;
1707 err = read_lsave(c);
1708 if (err)
1709 return err;
1710 }
1711
1712 for (i = 0; i < c->lpt_lebs; i++)
1713 if (c->ltab[i].free == c->leb_size) {
1714 err = ubifs_leb_unmap(c, i + c->lpt_first);
1715 if (err)
1716 return err;
1717 }
1718
1719 return 0;
1720 }
1721 #endif
1722
1723 /**
1724 * ubifs_lpt_init - initialize the LPT.
1725 * @c: UBIFS file-system description object
1726 * @rd: whether to initialize lpt for reading
1727 * @wr: whether to initialize lpt for writing
1728 *
1729 * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
1730 * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
1731 * true.
1732 *
1733 * This function returns %0 on success and a negative error code on failure.
1734 */
ubifs_lpt_init(struct ubifs_info * c,int rd,int wr)1735 int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
1736 {
1737 int err;
1738
1739 if (rd) {
1740 err = lpt_init_rd(c);
1741 if (err)
1742 goto out_err;
1743 }
1744
1745 #ifndef __UBOOT__
1746 if (wr) {
1747 err = lpt_init_wr(c);
1748 if (err)
1749 goto out_err;
1750 }
1751 #endif
1752
1753 return 0;
1754
1755 out_err:
1756 #ifndef __UBOOT__
1757 if (wr)
1758 ubifs_lpt_free(c, 1);
1759 #endif
1760 if (rd)
1761 ubifs_lpt_free(c, 0);
1762 return err;
1763 }
1764
1765 /**
1766 * struct lpt_scan_node - somewhere to put nodes while we scan LPT.
1767 * @nnode: where to keep a nnode
1768 * @pnode: where to keep a pnode
1769 * @cnode: where to keep a cnode
1770 * @in_tree: is the node in the tree in memory
1771 * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in
1772 * the tree
1773 * @ptr.pnode: ditto for pnode
1774 * @ptr.cnode: ditto for cnode
1775 */
1776 struct lpt_scan_node {
1777 union {
1778 struct ubifs_nnode nnode;
1779 struct ubifs_pnode pnode;
1780 struct ubifs_cnode cnode;
1781 };
1782 int in_tree;
1783 union {
1784 struct ubifs_nnode *nnode;
1785 struct ubifs_pnode *pnode;
1786 struct ubifs_cnode *cnode;
1787 } ptr;
1788 };
1789
1790 /**
1791 * scan_get_nnode - for the scan, get a nnode from either the tree or flash.
1792 * @c: the UBIFS file-system description object
1793 * @path: where to put the nnode
1794 * @parent: parent of the nnode
1795 * @iip: index in parent of the nnode
1796 *
1797 * This function returns a pointer to the nnode on success or a negative error
1798 * code on failure.
1799 */
scan_get_nnode(struct ubifs_info * c,struct lpt_scan_node * path,struct ubifs_nnode * parent,int iip)1800 static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
1801 struct lpt_scan_node *path,
1802 struct ubifs_nnode *parent, int iip)
1803 {
1804 struct ubifs_nbranch *branch;
1805 struct ubifs_nnode *nnode;
1806 void *buf = c->lpt_nod_buf;
1807 int err;
1808
1809 branch = &parent->nbranch[iip];
1810 nnode = branch->nnode;
1811 if (nnode) {
1812 path->in_tree = 1;
1813 path->ptr.nnode = nnode;
1814 return nnode;
1815 }
1816 nnode = &path->nnode;
1817 path->in_tree = 0;
1818 path->ptr.nnode = nnode;
1819 memset(nnode, 0, sizeof(struct ubifs_nnode));
1820 if (branch->lnum == 0) {
1821 /*
1822 * This nnode was not written which just means that the LEB
1823 * properties in the subtree below it describe empty LEBs. We
1824 * make the nnode as though we had read it, which in fact means
1825 * doing almost nothing.
1826 */
1827 if (c->big_lpt)
1828 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1829 } else {
1830 err = ubifs_leb_read(c, branch->lnum, buf, branch->offs,
1831 c->nnode_sz, 1);
1832 if (err)
1833 return ERR_PTR(err);
1834 err = ubifs_unpack_nnode(c, buf, nnode);
1835 if (err)
1836 return ERR_PTR(err);
1837 }
1838 err = validate_nnode(c, nnode, parent, iip);
1839 if (err)
1840 return ERR_PTR(err);
1841 if (!c->big_lpt)
1842 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1843 nnode->level = parent->level - 1;
1844 nnode->parent = parent;
1845 nnode->iip = iip;
1846 return nnode;
1847 }
1848
1849 /**
1850 * scan_get_pnode - for the scan, get a pnode from either the tree or flash.
1851 * @c: the UBIFS file-system description object
1852 * @path: where to put the pnode
1853 * @parent: parent of the pnode
1854 * @iip: index in parent of the pnode
1855 *
1856 * This function returns a pointer to the pnode on success or a negative error
1857 * code on failure.
1858 */
scan_get_pnode(struct ubifs_info * c,struct lpt_scan_node * path,struct ubifs_nnode * parent,int iip)1859 static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c,
1860 struct lpt_scan_node *path,
1861 struct ubifs_nnode *parent, int iip)
1862 {
1863 struct ubifs_nbranch *branch;
1864 struct ubifs_pnode *pnode;
1865 void *buf = c->lpt_nod_buf;
1866 int err;
1867
1868 branch = &parent->nbranch[iip];
1869 pnode = branch->pnode;
1870 if (pnode) {
1871 path->in_tree = 1;
1872 path->ptr.pnode = pnode;
1873 return pnode;
1874 }
1875 pnode = &path->pnode;
1876 path->in_tree = 0;
1877 path->ptr.pnode = pnode;
1878 memset(pnode, 0, sizeof(struct ubifs_pnode));
1879 if (branch->lnum == 0) {
1880 /*
1881 * This pnode was not written which just means that the LEB
1882 * properties in it describe empty LEBs. We make the pnode as
1883 * though we had read it.
1884 */
1885 int i;
1886
1887 if (c->big_lpt)
1888 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1889 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1890 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1891
1892 lprops->free = c->leb_size;
1893 lprops->flags = ubifs_categorize_lprops(c, lprops);
1894 }
1895 } else {
1896 ubifs_assert(branch->lnum >= c->lpt_first &&
1897 branch->lnum <= c->lpt_last);
1898 ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size);
1899 err = ubifs_leb_read(c, branch->lnum, buf, branch->offs,
1900 c->pnode_sz, 1);
1901 if (err)
1902 return ERR_PTR(err);
1903 err = unpack_pnode(c, buf, pnode);
1904 if (err)
1905 return ERR_PTR(err);
1906 }
1907 err = validate_pnode(c, pnode, parent, iip);
1908 if (err)
1909 return ERR_PTR(err);
1910 if (!c->big_lpt)
1911 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1912 pnode->parent = parent;
1913 pnode->iip = iip;
1914 set_pnode_lnum(c, pnode);
1915 return pnode;
1916 }
1917
1918 /**
1919 * ubifs_lpt_scan_nolock - scan the LPT.
1920 * @c: the UBIFS file-system description object
1921 * @start_lnum: LEB number from which to start scanning
1922 * @end_lnum: LEB number at which to stop scanning
1923 * @scan_cb: callback function called for each lprops
1924 * @data: data to be passed to the callback function
1925 *
1926 * This function returns %0 on success and a negative error code on failure.
1927 */
ubifs_lpt_scan_nolock(struct ubifs_info * c,int start_lnum,int end_lnum,ubifs_lpt_scan_callback scan_cb,void * data)1928 int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
1929 ubifs_lpt_scan_callback scan_cb, void *data)
1930 {
1931 int err = 0, i, h, iip, shft;
1932 struct ubifs_nnode *nnode;
1933 struct ubifs_pnode *pnode;
1934 struct lpt_scan_node *path;
1935
1936 if (start_lnum == -1) {
1937 start_lnum = end_lnum + 1;
1938 if (start_lnum >= c->leb_cnt)
1939 start_lnum = c->main_first;
1940 }
1941
1942 ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt);
1943 ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt);
1944
1945 if (!c->nroot) {
1946 err = ubifs_read_nnode(c, NULL, 0);
1947 if (err)
1948 return err;
1949 }
1950
1951 path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
1952 GFP_NOFS);
1953 if (!path)
1954 return -ENOMEM;
1955
1956 path[0].ptr.nnode = c->nroot;
1957 path[0].in_tree = 1;
1958 again:
1959 /* Descend to the pnode containing start_lnum */
1960 nnode = c->nroot;
1961 i = start_lnum - c->main_first;
1962 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1963 for (h = 1; h < c->lpt_hght; h++) {
1964 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1965 shft -= UBIFS_LPT_FANOUT_SHIFT;
1966 nnode = scan_get_nnode(c, path + h, nnode, iip);
1967 if (IS_ERR(nnode)) {
1968 err = PTR_ERR(nnode);
1969 goto out;
1970 }
1971 }
1972 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1973 pnode = scan_get_pnode(c, path + h, nnode, iip);
1974 if (IS_ERR(pnode)) {
1975 err = PTR_ERR(pnode);
1976 goto out;
1977 }
1978 iip = (i & (UBIFS_LPT_FANOUT - 1));
1979
1980 /* Loop for each lprops */
1981 while (1) {
1982 struct ubifs_lprops *lprops = &pnode->lprops[iip];
1983 int ret, lnum = lprops->lnum;
1984
1985 ret = scan_cb(c, lprops, path[h].in_tree, data);
1986 if (ret < 0) {
1987 err = ret;
1988 goto out;
1989 }
1990 if (ret & LPT_SCAN_ADD) {
1991 /* Add all the nodes in path to the tree in memory */
1992 for (h = 1; h < c->lpt_hght; h++) {
1993 const size_t sz = sizeof(struct ubifs_nnode);
1994 struct ubifs_nnode *parent;
1995
1996 if (path[h].in_tree)
1997 continue;
1998 nnode = kmemdup(&path[h].nnode, sz, GFP_NOFS);
1999 if (!nnode) {
2000 err = -ENOMEM;
2001 goto out;
2002 }
2003 parent = nnode->parent;
2004 parent->nbranch[nnode->iip].nnode = nnode;
2005 path[h].ptr.nnode = nnode;
2006 path[h].in_tree = 1;
2007 path[h + 1].cnode.parent = nnode;
2008 }
2009 if (path[h].in_tree)
2010 ubifs_ensure_cat(c, lprops);
2011 else {
2012 const size_t sz = sizeof(struct ubifs_pnode);
2013 struct ubifs_nnode *parent;
2014
2015 pnode = kmemdup(&path[h].pnode, sz, GFP_NOFS);
2016 if (!pnode) {
2017 err = -ENOMEM;
2018 goto out;
2019 }
2020 parent = pnode->parent;
2021 parent->nbranch[pnode->iip].pnode = pnode;
2022 path[h].ptr.pnode = pnode;
2023 path[h].in_tree = 1;
2024 update_cats(c, pnode);
2025 c->pnodes_have += 1;
2026 }
2027 err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)
2028 c->nroot, 0, 0);
2029 if (err)
2030 goto out;
2031 err = dbg_check_cats(c);
2032 if (err)
2033 goto out;
2034 }
2035 if (ret & LPT_SCAN_STOP) {
2036 err = 0;
2037 break;
2038 }
2039 /* Get the next lprops */
2040 if (lnum == end_lnum) {
2041 /*
2042 * We got to the end without finding what we were
2043 * looking for
2044 */
2045 err = -ENOSPC;
2046 goto out;
2047 }
2048 if (lnum + 1 >= c->leb_cnt) {
2049 /* Wrap-around to the beginning */
2050 start_lnum = c->main_first;
2051 goto again;
2052 }
2053 if (iip + 1 < UBIFS_LPT_FANOUT) {
2054 /* Next lprops is in the same pnode */
2055 iip += 1;
2056 continue;
2057 }
2058 /* We need to get the next pnode. Go up until we can go right */
2059 iip = pnode->iip;
2060 while (1) {
2061 h -= 1;
2062 ubifs_assert(h >= 0);
2063 nnode = path[h].ptr.nnode;
2064 if (iip + 1 < UBIFS_LPT_FANOUT)
2065 break;
2066 iip = nnode->iip;
2067 }
2068 /* Go right */
2069 iip += 1;
2070 /* Descend to the pnode */
2071 h += 1;
2072 for (; h < c->lpt_hght; h++) {
2073 nnode = scan_get_nnode(c, path + h, nnode, iip);
2074 if (IS_ERR(nnode)) {
2075 err = PTR_ERR(nnode);
2076 goto out;
2077 }
2078 iip = 0;
2079 }
2080 pnode = scan_get_pnode(c, path + h, nnode, iip);
2081 if (IS_ERR(pnode)) {
2082 err = PTR_ERR(pnode);
2083 goto out;
2084 }
2085 iip = 0;
2086 }
2087 out:
2088 kfree(path);
2089 return err;
2090 }
2091
2092 /**
2093 * dbg_chk_pnode - check a pnode.
2094 * @c: the UBIFS file-system description object
2095 * @pnode: pnode to check
2096 * @col: pnode column
2097 *
2098 * This function returns %0 on success and a negative error code on failure.
2099 */
dbg_chk_pnode(struct ubifs_info * c,struct ubifs_pnode * pnode,int col)2100 static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
2101 int col)
2102 {
2103 int i;
2104
2105 if (pnode->num != col) {
2106 ubifs_err(c, "pnode num %d expected %d parent num %d iip %d",
2107 pnode->num, col, pnode->parent->num, pnode->iip);
2108 return -EINVAL;
2109 }
2110 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
2111 struct ubifs_lprops *lp, *lprops = &pnode->lprops[i];
2112 int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i +
2113 c->main_first;
2114 int found, cat = lprops->flags & LPROPS_CAT_MASK;
2115 struct ubifs_lpt_heap *heap;
2116 struct list_head *list = NULL;
2117
2118 if (lnum >= c->leb_cnt)
2119 continue;
2120 if (lprops->lnum != lnum) {
2121 ubifs_err(c, "bad LEB number %d expected %d",
2122 lprops->lnum, lnum);
2123 return -EINVAL;
2124 }
2125 if (lprops->flags & LPROPS_TAKEN) {
2126 if (cat != LPROPS_UNCAT) {
2127 ubifs_err(c, "LEB %d taken but not uncat %d",
2128 lprops->lnum, cat);
2129 return -EINVAL;
2130 }
2131 continue;
2132 }
2133 if (lprops->flags & LPROPS_INDEX) {
2134 switch (cat) {
2135 case LPROPS_UNCAT:
2136 case LPROPS_DIRTY_IDX:
2137 case LPROPS_FRDI_IDX:
2138 break;
2139 default:
2140 ubifs_err(c, "LEB %d index but cat %d",
2141 lprops->lnum, cat);
2142 return -EINVAL;
2143 }
2144 } else {
2145 switch (cat) {
2146 case LPROPS_UNCAT:
2147 case LPROPS_DIRTY:
2148 case LPROPS_FREE:
2149 case LPROPS_EMPTY:
2150 case LPROPS_FREEABLE:
2151 break;
2152 default:
2153 ubifs_err(c, "LEB %d not index but cat %d",
2154 lprops->lnum, cat);
2155 return -EINVAL;
2156 }
2157 }
2158 switch (cat) {
2159 case LPROPS_UNCAT:
2160 list = &c->uncat_list;
2161 break;
2162 case LPROPS_EMPTY:
2163 list = &c->empty_list;
2164 break;
2165 case LPROPS_FREEABLE:
2166 list = &c->freeable_list;
2167 break;
2168 case LPROPS_FRDI_IDX:
2169 list = &c->frdi_idx_list;
2170 break;
2171 }
2172 found = 0;
2173 switch (cat) {
2174 case LPROPS_DIRTY:
2175 case LPROPS_DIRTY_IDX:
2176 case LPROPS_FREE:
2177 heap = &c->lpt_heap[cat - 1];
2178 if (lprops->hpos < heap->cnt &&
2179 heap->arr[lprops->hpos] == lprops)
2180 found = 1;
2181 break;
2182 case LPROPS_UNCAT:
2183 case LPROPS_EMPTY:
2184 case LPROPS_FREEABLE:
2185 case LPROPS_FRDI_IDX:
2186 list_for_each_entry(lp, list, list)
2187 if (lprops == lp) {
2188 found = 1;
2189 break;
2190 }
2191 break;
2192 }
2193 if (!found) {
2194 ubifs_err(c, "LEB %d cat %d not found in cat heap/list",
2195 lprops->lnum, cat);
2196 return -EINVAL;
2197 }
2198 switch (cat) {
2199 case LPROPS_EMPTY:
2200 if (lprops->free != c->leb_size) {
2201 ubifs_err(c, "LEB %d cat %d free %d dirty %d",
2202 lprops->lnum, cat, lprops->free,
2203 lprops->dirty);
2204 return -EINVAL;
2205 }
2206 break;
2207 case LPROPS_FREEABLE:
2208 case LPROPS_FRDI_IDX:
2209 if (lprops->free + lprops->dirty != c->leb_size) {
2210 ubifs_err(c, "LEB %d cat %d free %d dirty %d",
2211 lprops->lnum, cat, lprops->free,
2212 lprops->dirty);
2213 return -EINVAL;
2214 }
2215 break;
2216 }
2217 }
2218 return 0;
2219 }
2220
2221 /**
2222 * dbg_check_lpt_nodes - check nnodes and pnodes.
2223 * @c: the UBIFS file-system description object
2224 * @cnode: next cnode (nnode or pnode) to check
2225 * @row: row of cnode (root is zero)
2226 * @col: column of cnode (leftmost is zero)
2227 *
2228 * This function returns %0 on success and a negative error code on failure.
2229 */
dbg_check_lpt_nodes(struct ubifs_info * c,struct ubifs_cnode * cnode,int row,int col)2230 int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
2231 int row, int col)
2232 {
2233 struct ubifs_nnode *nnode, *nn;
2234 struct ubifs_cnode *cn;
2235 int num, iip = 0, err;
2236
2237 if (!dbg_is_chk_lprops(c))
2238 return 0;
2239
2240 while (cnode) {
2241 ubifs_assert(row >= 0);
2242 nnode = cnode->parent;
2243 if (cnode->level) {
2244 /* cnode is a nnode */
2245 num = calc_nnode_num(row, col);
2246 if (cnode->num != num) {
2247 ubifs_err(c, "nnode num %d expected %d parent num %d iip %d",
2248 cnode->num, num,
2249 (nnode ? nnode->num : 0), cnode->iip);
2250 return -EINVAL;
2251 }
2252 nn = (struct ubifs_nnode *)cnode;
2253 while (iip < UBIFS_LPT_FANOUT) {
2254 cn = nn->nbranch[iip].cnode;
2255 if (cn) {
2256 /* Go down */
2257 row += 1;
2258 col <<= UBIFS_LPT_FANOUT_SHIFT;
2259 col += iip;
2260 iip = 0;
2261 cnode = cn;
2262 break;
2263 }
2264 /* Go right */
2265 iip += 1;
2266 }
2267 if (iip < UBIFS_LPT_FANOUT)
2268 continue;
2269 } else {
2270 struct ubifs_pnode *pnode;
2271
2272 /* cnode is a pnode */
2273 pnode = (struct ubifs_pnode *)cnode;
2274 err = dbg_chk_pnode(c, pnode, col);
2275 if (err)
2276 return err;
2277 }
2278 /* Go up and to the right */
2279 row -= 1;
2280 col >>= UBIFS_LPT_FANOUT_SHIFT;
2281 iip = cnode->iip + 1;
2282 cnode = (struct ubifs_cnode *)nnode;
2283 }
2284 return 0;
2285 }
2286