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authorArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2008-07-14 12:08:37 -0400
committerArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2008-07-15 10:35:15 -0400
commit1e51764a3c2ac05a23a22b2a95ddee4d9bffb16d (patch)
tree919debdd48aef9eee9ff0e8f465ef2649325b993 /fs/ubifs/lpt.c
parente56a99d5a42dcb91e622ae7a0289d8fb2ddabffb (diff)
UBIFS: add new flash file system
This is a new flash file system. See http://www.linux-mtd.infradead.org/doc/ubifs.html Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Diffstat (limited to 'fs/ubifs/lpt.c')
-rw-r--r--fs/ubifs/lpt.c2243
1 files changed, 2243 insertions, 0 deletions
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
new file mode 100644
index 000000000000..9ff2463177e5
--- /dev/null
+++ b/fs/ubifs/lpt.c
@@ -0,0 +1,2243 @@
1/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Adrian Hunter
20 * Artem Bityutskiy (Битюцкий Артём)
21 */
22
23/*
24 * This file implements the LEB properties tree (LPT) area. The LPT area
25 * contains the LEB properties tree, a table of LPT area eraseblocks (ltab), and
26 * (for the "big" model) a table of saved LEB numbers (lsave). The LPT area sits
27 * between the log and the orphan area.
28 *
29 * The LPT area is like a miniature self-contained file system. It is required
30 * that it never runs out of space, is fast to access and update, and scales
31 * logarithmically. The LEB properties tree is implemented as a wandering tree
32 * much like the TNC, and the LPT area has its own garbage collection.
33 *
34 * The LPT has two slightly different forms called the "small model" and the
35 * "big model". The small model is used when the entire LEB properties table
36 * can be written into a single eraseblock. In that case, garbage collection
37 * consists of just writing the whole table, which therefore makes all other
38 * eraseblocks reusable. In the case of the big model, dirty eraseblocks are
39 * selected for garbage collection, which consists are marking the nodes in
40 * that LEB as dirty, and then only the dirty nodes are written out. Also, in
41 * the case of the big model, a table of LEB numbers is saved so that the entire
42 * LPT does not to be scanned looking for empty eraseblocks when UBIFS is first
43 * mounted.
44 */
45
46#include <linux/crc16.h>
47#include "ubifs.h"
48
49/**
50 * do_calc_lpt_geom - calculate sizes for the LPT area.
51 * @c: the UBIFS file-system description object
52 *
53 * Calculate the sizes of LPT bit fields, nodes, and tree, based on the
54 * properties of the flash and whether LPT is "big" (c->big_lpt).
55 */
56static void do_calc_lpt_geom(struct ubifs_info *c)
57{
58 int i, n, bits, per_leb_wastage, max_pnode_cnt;
59 long long sz, tot_wastage;
60
61 n = c->main_lebs + c->max_leb_cnt - c->leb_cnt;
62 max_pnode_cnt = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
63
64 c->lpt_hght = 1;
65 n = UBIFS_LPT_FANOUT;
66 while (n < max_pnode_cnt) {
67 c->lpt_hght += 1;
68 n <<= UBIFS_LPT_FANOUT_SHIFT;
69 }
70
71 c->pnode_cnt = DIV_ROUND_UP(c->main_lebs, UBIFS_LPT_FANOUT);
72
73 n = DIV_ROUND_UP(c->pnode_cnt, UBIFS_LPT_FANOUT);
74 c->nnode_cnt = n;
75 for (i = 1; i < c->lpt_hght; i++) {
76 n = DIV_ROUND_UP(n, UBIFS_LPT_FANOUT);
77 c->nnode_cnt += n;
78 }
79
80 c->space_bits = fls(c->leb_size) - 3;
81 c->lpt_lnum_bits = fls(c->lpt_lebs);
82 c->lpt_offs_bits = fls(c->leb_size - 1);
83 c->lpt_spc_bits = fls(c->leb_size);
84
85 n = DIV_ROUND_UP(c->max_leb_cnt, UBIFS_LPT_FANOUT);
86 c->pcnt_bits = fls(n - 1);
87
88 c->lnum_bits = fls(c->max_leb_cnt - 1);
89
90 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
91 (c->big_lpt ? c->pcnt_bits : 0) +
92 (c->space_bits * 2 + 1) * UBIFS_LPT_FANOUT;
93 c->pnode_sz = (bits + 7) / 8;
94
95 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
96 (c->big_lpt ? c->pcnt_bits : 0) +
97 (c->lpt_lnum_bits + c->lpt_offs_bits) * UBIFS_LPT_FANOUT;
98 c->nnode_sz = (bits + 7) / 8;
99
100 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
101 c->lpt_lebs * c->lpt_spc_bits * 2;
102 c->ltab_sz = (bits + 7) / 8;
103
104 bits = UBIFS_LPT_CRC_BITS + UBIFS_LPT_TYPE_BITS +
105 c->lnum_bits * c->lsave_cnt;
106 c->lsave_sz = (bits + 7) / 8;
107
108 /* Calculate the minimum LPT size */
109 c->lpt_sz = (long long)c->pnode_cnt * c->pnode_sz;
110 c->lpt_sz += (long long)c->nnode_cnt * c->nnode_sz;
111 c->lpt_sz += c->ltab_sz;
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 */
134int ubifs_calc_lpt_geom(struct ubifs_info *c)
135{
136 int lebs_needed;
137 uint64_t 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 sz += c->leb_size - 1;
144 do_div(sz, c->leb_size);
145 lebs_needed = sz;
146 if (lebs_needed > c->lpt_lebs) {
147 ubifs_err("too few LPT LEBs");
148 return -EINVAL;
149 }
150
151 /* Verify that ltab fits in a single LEB (since ltab is a single node */
152 if (c->ltab_sz > c->leb_size) {
153 ubifs_err("LPT ltab too big");
154 return -EINVAL;
155 }
156
157 c->check_lpt_free = c->big_lpt;
158
159 return 0;
160}
161
162/**
163 * calc_dflt_lpt_geom - calculate default LPT geometry.
164 * @c: the UBIFS file-system description object
165 * @main_lebs: number of main area LEBs is passed and returned here
166 * @big_lpt: whether the LPT area is "big" is returned here
167 *
168 * The size of the LPT area depends on parameters that themselves are dependent
169 * on the size of the LPT area. This function, successively recalculates the LPT
170 * area geometry until the parameters and resultant geometry are consistent.
171 *
172 * This function returns %0 on success and a negative error code on failure.
173 */
174static int calc_dflt_lpt_geom(struct ubifs_info *c, int *main_lebs,
175 int *big_lpt)
176{
177 int i, lebs_needed;
178 uint64_t sz;
179
180 /* Start by assuming the minimum number of LPT LEBs */
181 c->lpt_lebs = UBIFS_MIN_LPT_LEBS;
182 c->main_lebs = *main_lebs - c->lpt_lebs;
183 if (c->main_lebs <= 0)
184 return -EINVAL;
185
186 /* And assume we will use the small LPT model */
187 c->big_lpt = 0;
188
189 /*
190 * Calculate the geometry based on assumptions above and then see if it
191 * makes sense
192 */
193 do_calc_lpt_geom(c);
194
195 /* Small LPT model must have lpt_sz < leb_size */
196 if (c->lpt_sz > c->leb_size) {
197 /* Nope, so try again using big LPT model */
198 c->big_lpt = 1;
199 do_calc_lpt_geom(c);
200 }
201
202 /* Now check there are enough LPT LEBs */
203 for (i = 0; i < 64 ; i++) {
204 sz = c->lpt_sz * 4; /* Allow 4 times the size */
205 sz += c->leb_size - 1;
206 do_div(sz, c->leb_size);
207 lebs_needed = sz;
208 if (lebs_needed > c->lpt_lebs) {
209 /* Not enough LPT LEBs so try again with more */
210 c->lpt_lebs = lebs_needed;
211 c->main_lebs = *main_lebs - c->lpt_lebs;
212 if (c->main_lebs <= 0)
213 return -EINVAL;
214 do_calc_lpt_geom(c);
215 continue;
216 }
217 if (c->ltab_sz > c->leb_size) {
218 ubifs_err("LPT ltab too big");
219 return -EINVAL;
220 }
221 *main_lebs = c->main_lebs;
222 *big_lpt = c->big_lpt;
223 return 0;
224 }
225 return -EINVAL;
226}
227
228/**
229 * pack_bits - pack bit fields end-to-end.
230 * @addr: address at which to pack (passed and next address returned)
231 * @pos: bit position at which to pack (passed and next position returned)
232 * @val: value to pack
233 * @nrbits: number of bits of value to pack (1-32)
234 */
235static void pack_bits(uint8_t **addr, int *pos, uint32_t val, int nrbits)
236{
237 uint8_t *p = *addr;
238 int b = *pos;
239
240 ubifs_assert(nrbits > 0);
241 ubifs_assert(nrbits <= 32);
242 ubifs_assert(*pos >= 0);
243 ubifs_assert(*pos < 8);
244 ubifs_assert((val >> nrbits) == 0 || nrbits == 32);
245 if (b) {
246 *p |= ((uint8_t)val) << b;
247 nrbits += b;
248 if (nrbits > 8) {
249 *++p = (uint8_t)(val >>= (8 - b));
250 if (nrbits > 16) {
251 *++p = (uint8_t)(val >>= 8);
252 if (nrbits > 24) {
253 *++p = (uint8_t)(val >>= 8);
254 if (nrbits > 32)
255 *++p = (uint8_t)(val >>= 8);
256 }
257 }
258 }
259 } else {
260 *p = (uint8_t)val;
261 if (nrbits > 8) {
262 *++p = (uint8_t)(val >>= 8);
263 if (nrbits > 16) {
264 *++p = (uint8_t)(val >>= 8);
265 if (nrbits > 24)
266 *++p = (uint8_t)(val >>= 8);
267 }
268 }
269 }
270 b = nrbits & 7;
271 if (b == 0)
272 p++;
273 *addr = p;
274 *pos = b;
275}
276
277/**
278 * ubifs_unpack_bits - unpack bit fields.
279 * @addr: address at which to unpack (passed and next address returned)
280 * @pos: bit position at which to unpack (passed and next position returned)
281 * @nrbits: number of bits of value to unpack (1-32)
282 *
283 * This functions returns the value unpacked.
284 */
285uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits)
286{
287 const int k = 32 - nrbits;
288 uint8_t *p = *addr;
289 int b = *pos;
290 uint32_t val;
291
292 ubifs_assert(nrbits > 0);
293 ubifs_assert(nrbits <= 32);
294 ubifs_assert(*pos >= 0);
295 ubifs_assert(*pos < 8);
296 if (b) {
297 val = p[1] | ((uint32_t)p[2] << 8) | ((uint32_t)p[3] << 16) |
298 ((uint32_t)p[4] << 24);
299 val <<= (8 - b);
300 val |= *p >> b;
301 nrbits += b;
302 } else
303 val = p[0] | ((uint32_t)p[1] << 8) | ((uint32_t)p[2] << 16) |
304 ((uint32_t)p[3] << 24);
305 val <<= k;
306 val >>= k;
307 b = nrbits & 7;
308 p += nrbits / 8;
309 *addr = p;
310 *pos = b;
311 ubifs_assert((val >> nrbits) == 0 || nrbits - b == 32);
312 return val;
313}
314
315/**
316 * ubifs_pack_pnode - pack all the bit fields of a pnode.
317 * @c: UBIFS file-system description object
318 * @buf: buffer into which to pack
319 * @pnode: pnode to pack
320 */
321void ubifs_pack_pnode(struct ubifs_info *c, void *buf,
322 struct ubifs_pnode *pnode)
323{
324 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
325 int i, pos = 0;
326 uint16_t crc;
327
328 pack_bits(&addr, &pos, UBIFS_LPT_PNODE, UBIFS_LPT_TYPE_BITS);
329 if (c->big_lpt)
330 pack_bits(&addr, &pos, pnode->num, c->pcnt_bits);
331 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
332 pack_bits(&addr, &pos, pnode->lprops[i].free >> 3,
333 c->space_bits);
334 pack_bits(&addr, &pos, pnode->lprops[i].dirty >> 3,
335 c->space_bits);
336 if (pnode->lprops[i].flags & LPROPS_INDEX)
337 pack_bits(&addr, &pos, 1, 1);
338 else
339 pack_bits(&addr, &pos, 0, 1);
340 }
341 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
342 c->pnode_sz - UBIFS_LPT_CRC_BYTES);
343 addr = buf;
344 pos = 0;
345 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
346}
347
348/**
349 * ubifs_pack_nnode - pack all the bit fields of a nnode.
350 * @c: UBIFS file-system description object
351 * @buf: buffer into which to pack
352 * @nnode: nnode to pack
353 */
354void ubifs_pack_nnode(struct ubifs_info *c, void *buf,
355 struct ubifs_nnode *nnode)
356{
357 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
358 int i, pos = 0;
359 uint16_t crc;
360
361 pack_bits(&addr, &pos, UBIFS_LPT_NNODE, UBIFS_LPT_TYPE_BITS);
362 if (c->big_lpt)
363 pack_bits(&addr, &pos, nnode->num, c->pcnt_bits);
364 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
365 int lnum = nnode->nbranch[i].lnum;
366
367 if (lnum == 0)
368 lnum = c->lpt_last + 1;
369 pack_bits(&addr, &pos, lnum - c->lpt_first, c->lpt_lnum_bits);
370 pack_bits(&addr, &pos, nnode->nbranch[i].offs,
371 c->lpt_offs_bits);
372 }
373 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
374 c->nnode_sz - UBIFS_LPT_CRC_BYTES);
375 addr = buf;
376 pos = 0;
377 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
378}
379
380/**
381 * ubifs_pack_ltab - pack the LPT's own lprops table.
382 * @c: UBIFS file-system description object
383 * @buf: buffer into which to pack
384 * @ltab: LPT's own lprops table to pack
385 */
386void ubifs_pack_ltab(struct ubifs_info *c, void *buf,
387 struct ubifs_lpt_lprops *ltab)
388{
389 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
390 int i, pos = 0;
391 uint16_t crc;
392
393 pack_bits(&addr, &pos, UBIFS_LPT_LTAB, UBIFS_LPT_TYPE_BITS);
394 for (i = 0; i < c->lpt_lebs; i++) {
395 pack_bits(&addr, &pos, ltab[i].free, c->lpt_spc_bits);
396 pack_bits(&addr, &pos, ltab[i].dirty, c->lpt_spc_bits);
397 }
398 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
399 c->ltab_sz - UBIFS_LPT_CRC_BYTES);
400 addr = buf;
401 pos = 0;
402 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
403}
404
405/**
406 * ubifs_pack_lsave - pack the LPT's save table.
407 * @c: UBIFS file-system description object
408 * @buf: buffer into which to pack
409 * @lsave: LPT's save table to pack
410 */
411void ubifs_pack_lsave(struct ubifs_info *c, void *buf, int *lsave)
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_LSAVE, UBIFS_LPT_TYPE_BITS);
418 for (i = 0; i < c->lsave_cnt; i++)
419 pack_bits(&addr, &pos, lsave[i], c->lnum_bits);
420 crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
421 c->lsave_sz - UBIFS_LPT_CRC_BYTES);
422 addr = buf;
423 pos = 0;
424 pack_bits(&addr, &pos, crc, UBIFS_LPT_CRC_BITS);
425}
426
427/**
428 * ubifs_add_lpt_dirt - add dirty space to LPT LEB properties.
429 * @c: UBIFS file-system description object
430 * @lnum: LEB number to which to add dirty space
431 * @dirty: amount of dirty space to add
432 */
433void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty)
434{
435 if (!dirty || !lnum)
436 return;
437 dbg_lp("LEB %d add %d to %d",
438 lnum, dirty, c->ltab[lnum - c->lpt_first].dirty);
439 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
440 c->ltab[lnum - c->lpt_first].dirty += dirty;
441}
442
443/**
444 * set_ltab - set LPT LEB properties.
445 * @c: UBIFS file-system description object
446 * @lnum: LEB number
447 * @free: amount of free space
448 * @dirty: amount of dirty space
449 */
450static void set_ltab(struct ubifs_info *c, int lnum, int free, int dirty)
451{
452 dbg_lp("LEB %d free %d dirty %d to %d %d",
453 lnum, c->ltab[lnum - c->lpt_first].free,
454 c->ltab[lnum - c->lpt_first].dirty, free, dirty);
455 ubifs_assert(lnum >= c->lpt_first && lnum <= c->lpt_last);
456 c->ltab[lnum - c->lpt_first].free = free;
457 c->ltab[lnum - c->lpt_first].dirty = dirty;
458}
459
460/**
461 * ubifs_add_nnode_dirt - add dirty space to LPT LEB properties.
462 * @c: UBIFS file-system description object
463 * @nnode: nnode for which to add dirt
464 */
465void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode)
466{
467 struct ubifs_nnode *np = nnode->parent;
468
469 if (np)
470 ubifs_add_lpt_dirt(c, np->nbranch[nnode->iip].lnum,
471 c->nnode_sz);
472 else {
473 ubifs_add_lpt_dirt(c, c->lpt_lnum, c->nnode_sz);
474 if (!(c->lpt_drty_flgs & LTAB_DIRTY)) {
475 c->lpt_drty_flgs |= LTAB_DIRTY;
476 ubifs_add_lpt_dirt(c, c->ltab_lnum, c->ltab_sz);
477 }
478 }
479}
480
481/**
482 * add_pnode_dirt - add dirty space to LPT LEB properties.
483 * @c: UBIFS file-system description object
484 * @pnode: pnode for which to add dirt
485 */
486static void add_pnode_dirt(struct ubifs_info *c, struct ubifs_pnode *pnode)
487{
488 ubifs_add_lpt_dirt(c, pnode->parent->nbranch[pnode->iip].lnum,
489 c->pnode_sz);
490}
491
492/**
493 * calc_nnode_num - calculate nnode number.
494 * @row: the row in the tree (root is zero)
495 * @col: the column in the row (leftmost is zero)
496 *
497 * The nnode number is a number that uniquely identifies a nnode and can be used
498 * easily to traverse the tree from the root to that nnode.
499 *
500 * This function calculates and returns the nnode number for the nnode at @row
501 * and @col.
502 */
503static int calc_nnode_num(int row, int col)
504{
505 int num, bits;
506
507 num = 1;
508 while (row--) {
509 bits = (col & (UBIFS_LPT_FANOUT - 1));
510 col >>= UBIFS_LPT_FANOUT_SHIFT;
511 num <<= UBIFS_LPT_FANOUT_SHIFT;
512 num |= bits;
513 }
514 return num;
515}
516
517/**
518 * calc_nnode_num_from_parent - calculate nnode number.
519 * @c: UBIFS file-system description object
520 * @parent: parent nnode
521 * @iip: index in parent
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 based on the parent's
527 * nnode number and the index in parent.
528 */
529static int calc_nnode_num_from_parent(struct ubifs_info *c,
530 struct ubifs_nnode *parent, int iip)
531{
532 int num, shft;
533
534 if (!parent)
535 return 1;
536 shft = (c->lpt_hght - parent->level) * UBIFS_LPT_FANOUT_SHIFT;
537 num = parent->num ^ (1 << shft);
538 num |= (UBIFS_LPT_FANOUT + iip) << shft;
539 return num;
540}
541
542/**
543 * calc_pnode_num_from_parent - calculate pnode number.
544 * @c: UBIFS file-system description object
545 * @parent: parent nnode
546 * @iip: index in parent
547 *
548 * The pnode number is a number that uniquely identifies a pnode and can be used
549 * easily to traverse the tree from the root to that pnode.
550 *
551 * This function calculates and returns the pnode number based on the parent's
552 * nnode number and the index in parent.
553 */
554static int calc_pnode_num_from_parent(struct ubifs_info *c,
555 struct ubifs_nnode *parent, int iip)
556{
557 int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
558
559 for (i = 0; i < n; i++) {
560 num <<= UBIFS_LPT_FANOUT_SHIFT;
561 num |= pnum & (UBIFS_LPT_FANOUT - 1);
562 pnum >>= UBIFS_LPT_FANOUT_SHIFT;
563 }
564 num <<= UBIFS_LPT_FANOUT_SHIFT;
565 num |= iip;
566 return num;
567}
568
569/**
570 * ubifs_create_dflt_lpt - create default LPT.
571 * @c: UBIFS file-system description object
572 * @main_lebs: number of main area LEBs is passed and returned here
573 * @lpt_first: LEB number of first LPT LEB
574 * @lpt_lebs: number of LEBs for LPT is passed and returned here
575 * @big_lpt: use big LPT model is passed and returned here
576 *
577 * This function returns %0 on success and a negative error code on failure.
578 */
579int ubifs_create_dflt_lpt(struct ubifs_info *c, int *main_lebs, int lpt_first,
580 int *lpt_lebs, int *big_lpt)
581{
582 int lnum, err = 0, node_sz, iopos, i, j, cnt, len, alen, row;
583 int blnum, boffs, bsz, bcnt;
584 struct ubifs_pnode *pnode = NULL;
585 struct ubifs_nnode *nnode = NULL;
586 void *buf = NULL, *p;
587 struct ubifs_lpt_lprops *ltab = NULL;
588 int *lsave = NULL;
589
590 err = calc_dflt_lpt_geom(c, main_lebs, big_lpt);
591 if (err)
592 return err;
593 *lpt_lebs = c->lpt_lebs;
594
595 /* Needed by 'ubifs_pack_nnode()' and 'set_ltab()' */
596 c->lpt_first = lpt_first;
597 /* Needed by 'set_ltab()' */
598 c->lpt_last = lpt_first + c->lpt_lebs - 1;
599 /* Needed by 'ubifs_pack_lsave()' */
600 c->main_first = c->leb_cnt - *main_lebs;
601
602 lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_KERNEL);
603 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_KERNEL);
604 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_KERNEL);
605 buf = vmalloc(c->leb_size);
606 ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
607 if (!pnode || !nnode || !buf || !ltab || !lsave) {
608 err = -ENOMEM;
609 goto out;
610 }
611
612 ubifs_assert(!c->ltab);
613 c->ltab = ltab; /* Needed by set_ltab */
614
615 /* Initialize LPT's own lprops */
616 for (i = 0; i < c->lpt_lebs; i++) {
617 ltab[i].free = c->leb_size;
618 ltab[i].dirty = 0;
619 ltab[i].tgc = 0;
620 ltab[i].cmt = 0;
621 }
622
623 lnum = lpt_first;
624 p = buf;
625 /* Number of leaf nodes (pnodes) */
626 cnt = c->pnode_cnt;
627
628 /*
629 * The first pnode contains the LEB properties for the LEBs that contain
630 * the root inode node and the root index node of the index tree.
631 */
632 node_sz = ALIGN(ubifs_idx_node_sz(c, 1), 8);
633 iopos = ALIGN(node_sz, c->min_io_size);
634 pnode->lprops[0].free = c->leb_size - iopos;
635 pnode->lprops[0].dirty = iopos - node_sz;
636 pnode->lprops[0].flags = LPROPS_INDEX;
637
638 node_sz = UBIFS_INO_NODE_SZ;
639 iopos = ALIGN(node_sz, c->min_io_size);
640 pnode->lprops[1].free = c->leb_size - iopos;
641 pnode->lprops[1].dirty = iopos - node_sz;
642
643 for (i = 2; i < UBIFS_LPT_FANOUT; i++)
644 pnode->lprops[i].free = c->leb_size;
645
646 /* Add first pnode */
647 ubifs_pack_pnode(c, p, pnode);
648 p += c->pnode_sz;
649 len = c->pnode_sz;
650 pnode->num += 1;
651
652 /* Reset pnode values for remaining pnodes */
653 pnode->lprops[0].free = c->leb_size;
654 pnode->lprops[0].dirty = 0;
655 pnode->lprops[0].flags = 0;
656
657 pnode->lprops[1].free = c->leb_size;
658 pnode->lprops[1].dirty = 0;
659
660 /*
661 * To calculate the internal node branches, we keep information about
662 * the level below.
663 */
664 blnum = lnum; /* LEB number of level below */
665 boffs = 0; /* Offset of level below */
666 bcnt = cnt; /* Number of nodes in level below */
667 bsz = c->pnode_sz; /* Size of nodes in level below */
668
669 /* Add all remaining pnodes */
670 for (i = 1; i < cnt; i++) {
671 if (len + c->pnode_sz > c->leb_size) {
672 alen = ALIGN(len, c->min_io_size);
673 set_ltab(c, lnum, c->leb_size - alen, alen - len);
674 memset(p, 0xff, alen - len);
675 err = ubi_leb_change(c->ubi, lnum++, buf, alen,
676 UBI_SHORTTERM);
677 if (err)
678 goto out;
679 p = buf;
680 len = 0;
681 }
682 ubifs_pack_pnode(c, p, pnode);
683 p += c->pnode_sz;
684 len += c->pnode_sz;
685 /*
686 * pnodes are simply numbered left to right starting at zero,
687 * which means the pnode number can be used easily to traverse
688 * down the tree to the corresponding pnode.
689 */
690 pnode->num += 1;
691 }
692
693 row = 0;
694 for (i = UBIFS_LPT_FANOUT; cnt > i; i <<= UBIFS_LPT_FANOUT_SHIFT)
695 row += 1;
696 /* Add all nnodes, one level at a time */
697 while (1) {
698 /* Number of internal nodes (nnodes) at next level */
699 cnt = DIV_ROUND_UP(cnt, UBIFS_LPT_FANOUT);
700 for (i = 0; i < cnt; i++) {
701 if (len + c->nnode_sz > c->leb_size) {
702 alen = ALIGN(len, c->min_io_size);
703 set_ltab(c, lnum, c->leb_size - alen,
704 alen - len);
705 memset(p, 0xff, alen - len);
706 err = ubi_leb_change(c->ubi, lnum++, buf, alen,
707 UBI_SHORTTERM);
708 if (err)
709 goto out;
710 p = buf;
711 len = 0;
712 }
713 /* Only 1 nnode at this level, so it is the root */
714 if (cnt == 1) {
715 c->lpt_lnum = lnum;
716 c->lpt_offs = len;
717 }
718 /* Set branches to the level below */
719 for (j = 0; j < UBIFS_LPT_FANOUT; j++) {
720 if (bcnt) {
721 if (boffs + bsz > c->leb_size) {
722 blnum += 1;
723 boffs = 0;
724 }
725 nnode->nbranch[j].lnum = blnum;
726 nnode->nbranch[j].offs = boffs;
727 boffs += bsz;
728 bcnt--;
729 } else {
730 nnode->nbranch[j].lnum = 0;
731 nnode->nbranch[j].offs = 0;
732 }
733 }
734 nnode->num = calc_nnode_num(row, i);
735 ubifs_pack_nnode(c, p, nnode);
736 p += c->nnode_sz;
737 len += c->nnode_sz;
738 }
739 /* Only 1 nnode at this level, so it is the root */
740 if (cnt == 1)
741 break;
742 /* Update the information about the level below */
743 bcnt = cnt;
744 bsz = c->nnode_sz;
745 row -= 1;
746 }
747
748 if (*big_lpt) {
749 /* Need to add LPT's save table */
750 if (len + c->lsave_sz > c->leb_size) {
751 alen = ALIGN(len, c->min_io_size);
752 set_ltab(c, lnum, c->leb_size - alen, alen - len);
753 memset(p, 0xff, alen - len);
754 err = ubi_leb_change(c->ubi, lnum++, buf, alen,
755 UBI_SHORTTERM);
756 if (err)
757 goto out;
758 p = buf;
759 len = 0;
760 }
761
762 c->lsave_lnum = lnum;
763 c->lsave_offs = len;
764
765 for (i = 0; i < c->lsave_cnt && i < *main_lebs; i++)
766 lsave[i] = c->main_first + i;
767 for (; i < c->lsave_cnt; i++)
768 lsave[i] = c->main_first;
769
770 ubifs_pack_lsave(c, p, lsave);
771 p += c->lsave_sz;
772 len += c->lsave_sz;
773 }
774
775 /* Need to add LPT's own LEB properties table */
776 if (len + c->ltab_sz > c->leb_size) {
777 alen = ALIGN(len, c->min_io_size);
778 set_ltab(c, lnum, c->leb_size - alen, alen - len);
779 memset(p, 0xff, alen - len);
780 err = ubi_leb_change(c->ubi, lnum++, buf, alen, UBI_SHORTTERM);
781 if (err)
782 goto out;
783 p = buf;
784 len = 0;
785 }
786
787 c->ltab_lnum = lnum;
788 c->ltab_offs = len;
789
790 /* Update ltab before packing it */
791 len += c->ltab_sz;
792 alen = ALIGN(len, c->min_io_size);
793 set_ltab(c, lnum, c->leb_size - alen, alen - len);
794
795 ubifs_pack_ltab(c, p, ltab);
796 p += c->ltab_sz;
797
798 /* Write remaining buffer */
799 memset(p, 0xff, alen - len);
800 err = ubi_leb_change(c->ubi, lnum, buf, alen, UBI_SHORTTERM);
801 if (err)
802 goto out;
803
804 c->nhead_lnum = lnum;
805 c->nhead_offs = ALIGN(len, c->min_io_size);
806
807 dbg_lp("space_bits %d", c->space_bits);
808 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
809 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
810 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
811 dbg_lp("pcnt_bits %d", c->pcnt_bits);
812 dbg_lp("lnum_bits %d", c->lnum_bits);
813 dbg_lp("pnode_sz %d", c->pnode_sz);
814 dbg_lp("nnode_sz %d", c->nnode_sz);
815 dbg_lp("ltab_sz %d", c->ltab_sz);
816 dbg_lp("lsave_sz %d", c->lsave_sz);
817 dbg_lp("lsave_cnt %d", c->lsave_cnt);
818 dbg_lp("lpt_hght %d", c->lpt_hght);
819 dbg_lp("big_lpt %d", c->big_lpt);
820 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
821 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
822 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
823 if (c->big_lpt)
824 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
825out:
826 c->ltab = NULL;
827 kfree(lsave);
828 vfree(ltab);
829 vfree(buf);
830 kfree(nnode);
831 kfree(pnode);
832 return err;
833}
834
835/**
836 * update_cats - add LEB properties of a pnode to LEB category lists and heaps.
837 * @c: UBIFS file-system description object
838 * @pnode: pnode
839 *
840 * When a pnode is loaded into memory, the LEB properties it contains are added,
841 * by this function, to the LEB category lists and heaps.
842 */
843static void update_cats(struct ubifs_info *c, struct ubifs_pnode *pnode)
844{
845 int i;
846
847 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
848 int cat = pnode->lprops[i].flags & LPROPS_CAT_MASK;
849 int lnum = pnode->lprops[i].lnum;
850
851 if (!lnum)
852 return;
853 ubifs_add_to_cat(c, &pnode->lprops[i], cat);
854 }
855}
856
857/**
858 * replace_cats - add LEB properties of a pnode to LEB category lists and heaps.
859 * @c: UBIFS file-system description object
860 * @old_pnode: pnode copied
861 * @new_pnode: pnode copy
862 *
863 * During commit it is sometimes necessary to copy a pnode
864 * (see dirty_cow_pnode). When that happens, references in
865 * category lists and heaps must be replaced. This function does that.
866 */
867static void replace_cats(struct ubifs_info *c, struct ubifs_pnode *old_pnode,
868 struct ubifs_pnode *new_pnode)
869{
870 int i;
871
872 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
873 if (!new_pnode->lprops[i].lnum)
874 return;
875 ubifs_replace_cat(c, &old_pnode->lprops[i],
876 &new_pnode->lprops[i]);
877 }
878}
879
880/**
881 * check_lpt_crc - check LPT node crc is correct.
882 * @c: UBIFS file-system description object
883 * @buf: buffer containing node
884 * @len: length of node
885 *
886 * This function returns %0 on success and a negative error code on failure.
887 */
888static int check_lpt_crc(void *buf, int len)
889{
890 int pos = 0;
891 uint8_t *addr = buf;
892 uint16_t crc, calc_crc;
893
894 crc = ubifs_unpack_bits(&addr, &pos, UBIFS_LPT_CRC_BITS);
895 calc_crc = crc16(-1, buf + UBIFS_LPT_CRC_BYTES,
896 len - UBIFS_LPT_CRC_BYTES);
897 if (crc != calc_crc) {
898 ubifs_err("invalid crc in LPT node: crc %hx calc %hx", crc,
899 calc_crc);
900 dbg_dump_stack();
901 return -EINVAL;
902 }
903 return 0;
904}
905
906/**
907 * check_lpt_type - check LPT node type is correct.
908 * @c: UBIFS file-system description object
909 * @addr: address of type bit field is passed and returned updated here
910 * @pos: position of type bit field is passed and returned updated here
911 * @type: expected type
912 *
913 * This function returns %0 on success and a negative error code on failure.
914 */
915static int check_lpt_type(uint8_t **addr, int *pos, int type)
916{
917 int node_type;
918
919 node_type = ubifs_unpack_bits(addr, pos, UBIFS_LPT_TYPE_BITS);
920 if (node_type != type) {
921 ubifs_err("invalid type (%d) in LPT node type %d", node_type,
922 type);
923 dbg_dump_stack();
924 return -EINVAL;
925 }
926 return 0;
927}
928
929/**
930 * unpack_pnode - unpack a pnode.
931 * @c: UBIFS file-system description object
932 * @buf: buffer containing packed pnode to unpack
933 * @pnode: pnode structure to fill
934 *
935 * This function returns %0 on success and a negative error code on failure.
936 */
937static int unpack_pnode(struct ubifs_info *c, void *buf,
938 struct ubifs_pnode *pnode)
939{
940 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
941 int i, pos = 0, err;
942
943 err = check_lpt_type(&addr, &pos, UBIFS_LPT_PNODE);
944 if (err)
945 return err;
946 if (c->big_lpt)
947 pnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
948 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
949 struct ubifs_lprops * const lprops = &pnode->lprops[i];
950
951 lprops->free = ubifs_unpack_bits(&addr, &pos, c->space_bits);
952 lprops->free <<= 3;
953 lprops->dirty = ubifs_unpack_bits(&addr, &pos, c->space_bits);
954 lprops->dirty <<= 3;
955
956 if (ubifs_unpack_bits(&addr, &pos, 1))
957 lprops->flags = LPROPS_INDEX;
958 else
959 lprops->flags = 0;
960 lprops->flags |= ubifs_categorize_lprops(c, lprops);
961 }
962 err = check_lpt_crc(buf, c->pnode_sz);
963 return err;
964}
965
966/**
967 * unpack_nnode - unpack a nnode.
968 * @c: UBIFS file-system description object
969 * @buf: buffer containing packed nnode to unpack
970 * @nnode: nnode structure to fill
971 *
972 * This function returns %0 on success and a negative error code on failure.
973 */
974static int unpack_nnode(struct ubifs_info *c, void *buf,
975 struct ubifs_nnode *nnode)
976{
977 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
978 int i, pos = 0, err;
979
980 err = check_lpt_type(&addr, &pos, UBIFS_LPT_NNODE);
981 if (err)
982 return err;
983 if (c->big_lpt)
984 nnode->num = ubifs_unpack_bits(&addr, &pos, c->pcnt_bits);
985 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
986 int lnum;
987
988 lnum = ubifs_unpack_bits(&addr, &pos, c->lpt_lnum_bits) +
989 c->lpt_first;
990 if (lnum == c->lpt_last + 1)
991 lnum = 0;
992 nnode->nbranch[i].lnum = lnum;
993 nnode->nbranch[i].offs = ubifs_unpack_bits(&addr, &pos,
994 c->lpt_offs_bits);
995 }
996 err = check_lpt_crc(buf, c->nnode_sz);
997 return err;
998}
999
1000/**
1001 * unpack_ltab - unpack the LPT's own lprops table.
1002 * @c: UBIFS file-system description object
1003 * @buf: buffer from which to unpack
1004 *
1005 * This function returns %0 on success and a negative error code on failure.
1006 */
1007static int unpack_ltab(struct ubifs_info *c, void *buf)
1008{
1009 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1010 int i, pos = 0, err;
1011
1012 err = check_lpt_type(&addr, &pos, UBIFS_LPT_LTAB);
1013 if (err)
1014 return err;
1015 for (i = 0; i < c->lpt_lebs; i++) {
1016 int free = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1017 int dirty = ubifs_unpack_bits(&addr, &pos, c->lpt_spc_bits);
1018
1019 if (free < 0 || free > c->leb_size || dirty < 0 ||
1020 dirty > c->leb_size || free + dirty > c->leb_size)
1021 return -EINVAL;
1022
1023 c->ltab[i].free = free;
1024 c->ltab[i].dirty = dirty;
1025 c->ltab[i].tgc = 0;
1026 c->ltab[i].cmt = 0;
1027 }
1028 err = check_lpt_crc(buf, c->ltab_sz);
1029 return err;
1030}
1031
1032/**
1033 * unpack_lsave - unpack the LPT's save table.
1034 * @c: UBIFS file-system description object
1035 * @buf: buffer from which to unpack
1036 *
1037 * This function returns %0 on success and a negative error code on failure.
1038 */
1039static int unpack_lsave(struct ubifs_info *c, void *buf)
1040{
1041 uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
1042 int i, pos = 0, err;
1043
1044 err = check_lpt_type(&addr, &pos, UBIFS_LPT_LSAVE);
1045 if (err)
1046 return err;
1047 for (i = 0; i < c->lsave_cnt; i++) {
1048 int lnum = ubifs_unpack_bits(&addr, &pos, c->lnum_bits);
1049
1050 if (lnum < c->main_first || lnum >= c->leb_cnt)
1051 return -EINVAL;
1052 c->lsave[i] = lnum;
1053 }
1054 err = check_lpt_crc(buf, c->lsave_sz);
1055 return err;
1056}
1057
1058/**
1059 * validate_nnode - validate a nnode.
1060 * @c: UBIFS file-system description object
1061 * @nnode: nnode to validate
1062 * @parent: parent nnode (or NULL for the root nnode)
1063 * @iip: index in parent
1064 *
1065 * This function returns %0 on success and a negative error code on failure.
1066 */
1067static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
1068 struct ubifs_nnode *parent, int iip)
1069{
1070 int i, lvl, max_offs;
1071
1072 if (c->big_lpt) {
1073 int num = calc_nnode_num_from_parent(c, parent, iip);
1074
1075 if (nnode->num != num)
1076 return -EINVAL;
1077 }
1078 lvl = parent ? parent->level - 1 : c->lpt_hght;
1079 if (lvl < 1)
1080 return -EINVAL;
1081 if (lvl == 1)
1082 max_offs = c->leb_size - c->pnode_sz;
1083 else
1084 max_offs = c->leb_size - c->nnode_sz;
1085 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1086 int lnum = nnode->nbranch[i].lnum;
1087 int offs = nnode->nbranch[i].offs;
1088
1089 if (lnum == 0) {
1090 if (offs != 0)
1091 return -EINVAL;
1092 continue;
1093 }
1094 if (lnum < c->lpt_first || lnum > c->lpt_last)
1095 return -EINVAL;
1096 if (offs < 0 || offs > max_offs)
1097 return -EINVAL;
1098 }
1099 return 0;
1100}
1101
1102/**
1103 * validate_pnode - validate a pnode.
1104 * @c: UBIFS file-system description object
1105 * @pnode: pnode to validate
1106 * @parent: parent nnode
1107 * @iip: index in parent
1108 *
1109 * This function returns %0 on success and a negative error code on failure.
1110 */
1111static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
1112 struct ubifs_nnode *parent, int iip)
1113{
1114 int i;
1115
1116 if (c->big_lpt) {
1117 int num = calc_pnode_num_from_parent(c, parent, iip);
1118
1119 if (pnode->num != num)
1120 return -EINVAL;
1121 }
1122 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1123 int free = pnode->lprops[i].free;
1124 int dirty = pnode->lprops[i].dirty;
1125
1126 if (free < 0 || free > c->leb_size || free % c->min_io_size ||
1127 (free & 7))
1128 return -EINVAL;
1129 if (dirty < 0 || dirty > c->leb_size || (dirty & 7))
1130 return -EINVAL;
1131 if (dirty + free > c->leb_size)
1132 return -EINVAL;
1133 }
1134 return 0;
1135}
1136
1137/**
1138 * set_pnode_lnum - set LEB numbers on a pnode.
1139 * @c: UBIFS file-system description object
1140 * @pnode: pnode to update
1141 *
1142 * This function calculates the LEB numbers for the LEB properties it contains
1143 * based on the pnode number.
1144 */
1145static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode *pnode)
1146{
1147 int i, lnum;
1148
1149 lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + c->main_first;
1150 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1151 if (lnum >= c->leb_cnt)
1152 return;
1153 pnode->lprops[i].lnum = lnum++;
1154 }
1155}
1156
1157/**
1158 * ubifs_read_nnode - read a nnode from flash and link it to the tree in memory.
1159 * @c: UBIFS file-system description object
1160 * @parent: parent nnode (or NULL for the root)
1161 * @iip: index in parent
1162 *
1163 * This function returns %0 on success and a negative error code on failure.
1164 */
1165int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1166{
1167 struct ubifs_nbranch *branch = NULL;
1168 struct ubifs_nnode *nnode = NULL;
1169 void *buf = c->lpt_nod_buf;
1170 int err, lnum, offs;
1171
1172 if (parent) {
1173 branch = &parent->nbranch[iip];
1174 lnum = branch->lnum;
1175 offs = branch->offs;
1176 } else {
1177 lnum = c->lpt_lnum;
1178 offs = c->lpt_offs;
1179 }
1180 nnode = kzalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1181 if (!nnode) {
1182 err = -ENOMEM;
1183 goto out;
1184 }
1185 if (lnum == 0) {
1186 /*
1187 * This nnode was not written which just means that the LEB
1188 * properties in the subtree below it describe empty LEBs. We
1189 * make the nnode as though we had read it, which in fact means
1190 * doing almost nothing.
1191 */
1192 if (c->big_lpt)
1193 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1194 } else {
1195 err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
1196 if (err)
1197 goto out;
1198 err = unpack_nnode(c, buf, nnode);
1199 if (err)
1200 goto out;
1201 }
1202 err = validate_nnode(c, nnode, parent, iip);
1203 if (err)
1204 goto out;
1205 if (!c->big_lpt)
1206 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1207 if (parent) {
1208 branch->nnode = nnode;
1209 nnode->level = parent->level - 1;
1210 } else {
1211 c->nroot = nnode;
1212 nnode->level = c->lpt_hght;
1213 }
1214 nnode->parent = parent;
1215 nnode->iip = iip;
1216 return 0;
1217
1218out:
1219 ubifs_err("error %d reading nnode at %d:%d", err, lnum, offs);
1220 kfree(nnode);
1221 return err;
1222}
1223
1224/**
1225 * read_pnode - read a pnode from flash and link it to the tree in memory.
1226 * @c: UBIFS file-system description object
1227 * @parent: parent nnode
1228 * @iip: index in parent
1229 *
1230 * This function returns %0 on success and a negative error code on failure.
1231 */
1232static int read_pnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
1233{
1234 struct ubifs_nbranch *branch;
1235 struct ubifs_pnode *pnode = NULL;
1236 void *buf = c->lpt_nod_buf;
1237 int err, lnum, offs;
1238
1239 branch = &parent->nbranch[iip];
1240 lnum = branch->lnum;
1241 offs = branch->offs;
1242 pnode = kzalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1243 if (!pnode) {
1244 err = -ENOMEM;
1245 goto out;
1246 }
1247 if (lnum == 0) {
1248 /*
1249 * This pnode was not written which just means that the LEB
1250 * properties in it describe empty LEBs. We make the pnode as
1251 * though we had read it.
1252 */
1253 int i;
1254
1255 if (c->big_lpt)
1256 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1257 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1258 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1259
1260 lprops->free = c->leb_size;
1261 lprops->flags = ubifs_categorize_lprops(c, lprops);
1262 }
1263 } else {
1264 err = ubi_read(c->ubi, lnum, buf, offs, c->pnode_sz);
1265 if (err)
1266 goto out;
1267 err = unpack_pnode(c, buf, pnode);
1268 if (err)
1269 goto out;
1270 }
1271 err = validate_pnode(c, pnode, parent, iip);
1272 if (err)
1273 goto out;
1274 if (!c->big_lpt)
1275 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1276 branch->pnode = pnode;
1277 pnode->parent = parent;
1278 pnode->iip = iip;
1279 set_pnode_lnum(c, pnode);
1280 c->pnodes_have += 1;
1281 return 0;
1282
1283out:
1284 ubifs_err("error %d reading pnode at %d:%d", err, lnum, offs);
1285 dbg_dump_pnode(c, pnode, parent, iip);
1286 dbg_msg("calc num: %d", calc_pnode_num_from_parent(c, parent, iip));
1287 kfree(pnode);
1288 return err;
1289}
1290
1291/**
1292 * read_ltab - read LPT's own lprops table.
1293 * @c: UBIFS file-system description object
1294 *
1295 * This function returns %0 on success and a negative error code on failure.
1296 */
1297static int read_ltab(struct ubifs_info *c)
1298{
1299 int err;
1300 void *buf;
1301
1302 buf = vmalloc(c->ltab_sz);
1303 if (!buf)
1304 return -ENOMEM;
1305 err = ubi_read(c->ubi, c->ltab_lnum, buf, c->ltab_offs, c->ltab_sz);
1306 if (err)
1307 goto out;
1308 err = unpack_ltab(c, buf);
1309out:
1310 vfree(buf);
1311 return err;
1312}
1313
1314/**
1315 * read_lsave - read LPT's save table.
1316 * @c: UBIFS file-system description object
1317 *
1318 * This function returns %0 on success and a negative error code on failure.
1319 */
1320static int read_lsave(struct ubifs_info *c)
1321{
1322 int err, i;
1323 void *buf;
1324
1325 buf = vmalloc(c->lsave_sz);
1326 if (!buf)
1327 return -ENOMEM;
1328 err = ubi_read(c->ubi, c->lsave_lnum, buf, c->lsave_offs, c->lsave_sz);
1329 if (err)
1330 goto out;
1331 err = unpack_lsave(c, buf);
1332 if (err)
1333 goto out;
1334 for (i = 0; i < c->lsave_cnt; i++) {
1335 int lnum = c->lsave[i];
1336
1337 /*
1338 * Due to automatic resizing, the values in the lsave table
1339 * could be beyond the volume size - just ignore them.
1340 */
1341 if (lnum >= c->leb_cnt)
1342 continue;
1343 ubifs_lpt_lookup(c, lnum);
1344 }
1345out:
1346 vfree(buf);
1347 return err;
1348}
1349
1350/**
1351 * ubifs_get_nnode - get a nnode.
1352 * @c: UBIFS file-system description object
1353 * @parent: parent nnode (or NULL for the root)
1354 * @iip: index in parent
1355 *
1356 * This function returns a pointer to the nnode on success or a negative error
1357 * code on failure.
1358 */
1359struct ubifs_nnode *ubifs_get_nnode(struct ubifs_info *c,
1360 struct ubifs_nnode *parent, int iip)
1361{
1362 struct ubifs_nbranch *branch;
1363 struct ubifs_nnode *nnode;
1364 int err;
1365
1366 branch = &parent->nbranch[iip];
1367 nnode = branch->nnode;
1368 if (nnode)
1369 return nnode;
1370 err = ubifs_read_nnode(c, parent, iip);
1371 if (err)
1372 return ERR_PTR(err);
1373 return branch->nnode;
1374}
1375
1376/**
1377 * ubifs_get_pnode - get a pnode.
1378 * @c: UBIFS file-system description object
1379 * @parent: parent nnode
1380 * @iip: index in parent
1381 *
1382 * This function returns a pointer to the pnode on success or a negative error
1383 * code on failure.
1384 */
1385struct ubifs_pnode *ubifs_get_pnode(struct ubifs_info *c,
1386 struct ubifs_nnode *parent, int iip)
1387{
1388 struct ubifs_nbranch *branch;
1389 struct ubifs_pnode *pnode;
1390 int err;
1391
1392 branch = &parent->nbranch[iip];
1393 pnode = branch->pnode;
1394 if (pnode)
1395 return pnode;
1396 err = read_pnode(c, parent, iip);
1397 if (err)
1398 return ERR_PTR(err);
1399 update_cats(c, branch->pnode);
1400 return branch->pnode;
1401}
1402
1403/**
1404 * ubifs_lpt_lookup - lookup LEB properties in the LPT.
1405 * @c: UBIFS file-system description object
1406 * @lnum: LEB number to lookup
1407 *
1408 * This function returns a pointer to the LEB properties on success or a
1409 * negative error code on failure.
1410 */
1411struct ubifs_lprops *ubifs_lpt_lookup(struct ubifs_info *c, int lnum)
1412{
1413 int err, i, h, iip, shft;
1414 struct ubifs_nnode *nnode;
1415 struct ubifs_pnode *pnode;
1416
1417 if (!c->nroot) {
1418 err = ubifs_read_nnode(c, NULL, 0);
1419 if (err)
1420 return ERR_PTR(err);
1421 }
1422 nnode = c->nroot;
1423 i = lnum - c->main_first;
1424 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1425 for (h = 1; h < c->lpt_hght; h++) {
1426 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1427 shft -= UBIFS_LPT_FANOUT_SHIFT;
1428 nnode = ubifs_get_nnode(c, nnode, iip);
1429 if (IS_ERR(nnode))
1430 return ERR_PTR(PTR_ERR(nnode));
1431 }
1432 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1433 shft -= UBIFS_LPT_FANOUT_SHIFT;
1434 pnode = ubifs_get_pnode(c, nnode, iip);
1435 if (IS_ERR(pnode))
1436 return ERR_PTR(PTR_ERR(pnode));
1437 iip = (i & (UBIFS_LPT_FANOUT - 1));
1438 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1439 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1440 pnode->lprops[iip].flags);
1441 return &pnode->lprops[iip];
1442}
1443
1444/**
1445 * dirty_cow_nnode - ensure a nnode is not being committed.
1446 * @c: UBIFS file-system description object
1447 * @nnode: nnode to check
1448 *
1449 * Returns dirtied nnode on success or negative error code on failure.
1450 */
1451static struct ubifs_nnode *dirty_cow_nnode(struct ubifs_info *c,
1452 struct ubifs_nnode *nnode)
1453{
1454 struct ubifs_nnode *n;
1455 int i;
1456
1457 if (!test_bit(COW_CNODE, &nnode->flags)) {
1458 /* nnode is not being committed */
1459 if (!test_and_set_bit(DIRTY_CNODE, &nnode->flags)) {
1460 c->dirty_nn_cnt += 1;
1461 ubifs_add_nnode_dirt(c, nnode);
1462 }
1463 return nnode;
1464 }
1465
1466 /* nnode is being committed, so copy it */
1467 n = kmalloc(sizeof(struct ubifs_nnode), GFP_NOFS);
1468 if (unlikely(!n))
1469 return ERR_PTR(-ENOMEM);
1470
1471 memcpy(n, nnode, sizeof(struct ubifs_nnode));
1472 n->cnext = NULL;
1473 __set_bit(DIRTY_CNODE, &n->flags);
1474 __clear_bit(COW_CNODE, &n->flags);
1475
1476 /* The children now have new parent */
1477 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1478 struct ubifs_nbranch *branch = &n->nbranch[i];
1479
1480 if (branch->cnode)
1481 branch->cnode->parent = n;
1482 }
1483
1484 ubifs_assert(!test_bit(OBSOLETE_CNODE, &nnode->flags));
1485 __set_bit(OBSOLETE_CNODE, &nnode->flags);
1486
1487 c->dirty_nn_cnt += 1;
1488 ubifs_add_nnode_dirt(c, nnode);
1489 if (nnode->parent)
1490 nnode->parent->nbranch[n->iip].nnode = n;
1491 else
1492 c->nroot = n;
1493 return n;
1494}
1495
1496/**
1497 * dirty_cow_pnode - ensure a pnode is not being committed.
1498 * @c: UBIFS file-system description object
1499 * @pnode: pnode to check
1500 *
1501 * Returns dirtied pnode on success or negative error code on failure.
1502 */
1503static struct ubifs_pnode *dirty_cow_pnode(struct ubifs_info *c,
1504 struct ubifs_pnode *pnode)
1505{
1506 struct ubifs_pnode *p;
1507
1508 if (!test_bit(COW_CNODE, &pnode->flags)) {
1509 /* pnode is not being committed */
1510 if (!test_and_set_bit(DIRTY_CNODE, &pnode->flags)) {
1511 c->dirty_pn_cnt += 1;
1512 add_pnode_dirt(c, pnode);
1513 }
1514 return pnode;
1515 }
1516
1517 /* pnode is being committed, so copy it */
1518 p = kmalloc(sizeof(struct ubifs_pnode), GFP_NOFS);
1519 if (unlikely(!p))
1520 return ERR_PTR(-ENOMEM);
1521
1522 memcpy(p, pnode, sizeof(struct ubifs_pnode));
1523 p->cnext = NULL;
1524 __set_bit(DIRTY_CNODE, &p->flags);
1525 __clear_bit(COW_CNODE, &p->flags);
1526 replace_cats(c, pnode, p);
1527
1528 ubifs_assert(!test_bit(OBSOLETE_CNODE, &pnode->flags));
1529 __set_bit(OBSOLETE_CNODE, &pnode->flags);
1530
1531 c->dirty_pn_cnt += 1;
1532 add_pnode_dirt(c, pnode);
1533 pnode->parent->nbranch[p->iip].pnode = p;
1534 return p;
1535}
1536
1537/**
1538 * ubifs_lpt_lookup_dirty - lookup LEB properties in the LPT.
1539 * @c: UBIFS file-system description object
1540 * @lnum: LEB number to lookup
1541 *
1542 * This function returns a pointer to the LEB properties on success or a
1543 * negative error code on failure.
1544 */
1545struct ubifs_lprops *ubifs_lpt_lookup_dirty(struct ubifs_info *c, int lnum)
1546{
1547 int err, i, h, iip, shft;
1548 struct ubifs_nnode *nnode;
1549 struct ubifs_pnode *pnode;
1550
1551 if (!c->nroot) {
1552 err = ubifs_read_nnode(c, NULL, 0);
1553 if (err)
1554 return ERR_PTR(err);
1555 }
1556 nnode = c->nroot;
1557 nnode = dirty_cow_nnode(c, nnode);
1558 if (IS_ERR(nnode))
1559 return ERR_PTR(PTR_ERR(nnode));
1560 i = lnum - c->main_first;
1561 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1562 for (h = 1; h < c->lpt_hght; h++) {
1563 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1564 shft -= UBIFS_LPT_FANOUT_SHIFT;
1565 nnode = ubifs_get_nnode(c, nnode, iip);
1566 if (IS_ERR(nnode))
1567 return ERR_PTR(PTR_ERR(nnode));
1568 nnode = dirty_cow_nnode(c, nnode);
1569 if (IS_ERR(nnode))
1570 return ERR_PTR(PTR_ERR(nnode));
1571 }
1572 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1573 shft -= UBIFS_LPT_FANOUT_SHIFT;
1574 pnode = ubifs_get_pnode(c, nnode, iip);
1575 if (IS_ERR(pnode))
1576 return ERR_PTR(PTR_ERR(pnode));
1577 pnode = dirty_cow_pnode(c, pnode);
1578 if (IS_ERR(pnode))
1579 return ERR_PTR(PTR_ERR(pnode));
1580 iip = (i & (UBIFS_LPT_FANOUT - 1));
1581 dbg_lp("LEB %d, free %d, dirty %d, flags %d", lnum,
1582 pnode->lprops[iip].free, pnode->lprops[iip].dirty,
1583 pnode->lprops[iip].flags);
1584 ubifs_assert(test_bit(DIRTY_CNODE, &pnode->flags));
1585 return &pnode->lprops[iip];
1586}
1587
1588/**
1589 * lpt_init_rd - initialize the LPT for reading.
1590 * @c: UBIFS file-system description object
1591 *
1592 * This function returns %0 on success and a negative error code on failure.
1593 */
1594static int lpt_init_rd(struct ubifs_info *c)
1595{
1596 int err, i;
1597
1598 c->ltab = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1599 if (!c->ltab)
1600 return -ENOMEM;
1601
1602 i = max_t(int, c->nnode_sz, c->pnode_sz);
1603 c->lpt_nod_buf = kmalloc(i, GFP_KERNEL);
1604 if (!c->lpt_nod_buf)
1605 return -ENOMEM;
1606
1607 for (i = 0; i < LPROPS_HEAP_CNT; i++) {
1608 c->lpt_heap[i].arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ,
1609 GFP_KERNEL);
1610 if (!c->lpt_heap[i].arr)
1611 return -ENOMEM;
1612 c->lpt_heap[i].cnt = 0;
1613 c->lpt_heap[i].max_cnt = LPT_HEAP_SZ;
1614 }
1615
1616 c->dirty_idx.arr = kmalloc(sizeof(void *) * LPT_HEAP_SZ, GFP_KERNEL);
1617 if (!c->dirty_idx.arr)
1618 return -ENOMEM;
1619 c->dirty_idx.cnt = 0;
1620 c->dirty_idx.max_cnt = LPT_HEAP_SZ;
1621
1622 err = read_ltab(c);
1623 if (err)
1624 return err;
1625
1626 dbg_lp("space_bits %d", c->space_bits);
1627 dbg_lp("lpt_lnum_bits %d", c->lpt_lnum_bits);
1628 dbg_lp("lpt_offs_bits %d", c->lpt_offs_bits);
1629 dbg_lp("lpt_spc_bits %d", c->lpt_spc_bits);
1630 dbg_lp("pcnt_bits %d", c->pcnt_bits);
1631 dbg_lp("lnum_bits %d", c->lnum_bits);
1632 dbg_lp("pnode_sz %d", c->pnode_sz);
1633 dbg_lp("nnode_sz %d", c->nnode_sz);
1634 dbg_lp("ltab_sz %d", c->ltab_sz);
1635 dbg_lp("lsave_sz %d", c->lsave_sz);
1636 dbg_lp("lsave_cnt %d", c->lsave_cnt);
1637 dbg_lp("lpt_hght %d", c->lpt_hght);
1638 dbg_lp("big_lpt %d", c->big_lpt);
1639 dbg_lp("LPT root is at %d:%d", c->lpt_lnum, c->lpt_offs);
1640 dbg_lp("LPT head is at %d:%d", c->nhead_lnum, c->nhead_offs);
1641 dbg_lp("LPT ltab is at %d:%d", c->ltab_lnum, c->ltab_offs);
1642 if (c->big_lpt)
1643 dbg_lp("LPT lsave is at %d:%d", c->lsave_lnum, c->lsave_offs);
1644
1645 return 0;
1646}
1647
1648/**
1649 * lpt_init_wr - initialize the LPT for writing.
1650 * @c: UBIFS file-system description object
1651 *
1652 * 'lpt_init_rd()' must have been called already.
1653 *
1654 * This function returns %0 on success and a negative error code on failure.
1655 */
1656static int lpt_init_wr(struct ubifs_info *c)
1657{
1658 int err, i;
1659
1660 c->ltab_cmt = vmalloc(sizeof(struct ubifs_lpt_lprops) * c->lpt_lebs);
1661 if (!c->ltab_cmt)
1662 return -ENOMEM;
1663
1664 c->lpt_buf = vmalloc(c->leb_size);
1665 if (!c->lpt_buf)
1666 return -ENOMEM;
1667
1668 if (c->big_lpt) {
1669 c->lsave = kmalloc(sizeof(int) * c->lsave_cnt, GFP_NOFS);
1670 if (!c->lsave)
1671 return -ENOMEM;
1672 err = read_lsave(c);
1673 if (err)
1674 return err;
1675 }
1676
1677 for (i = 0; i < c->lpt_lebs; i++)
1678 if (c->ltab[i].free == c->leb_size) {
1679 err = ubifs_leb_unmap(c, i + c->lpt_first);
1680 if (err)
1681 return err;
1682 }
1683
1684 return 0;
1685}
1686
1687/**
1688 * ubifs_lpt_init - initialize the LPT.
1689 * @c: UBIFS file-system description object
1690 * @rd: whether to initialize lpt for reading
1691 * @wr: whether to initialize lpt for writing
1692 *
1693 * For mounting 'rw', @rd and @wr are both true. For mounting 'ro', @rd is true
1694 * and @wr is false. For mounting from 'ro' to 'rw', @rd is false and @wr is
1695 * true.
1696 *
1697 * This function returns %0 on success and a negative error code on failure.
1698 */
1699int ubifs_lpt_init(struct ubifs_info *c, int rd, int wr)
1700{
1701 int err;
1702
1703 if (rd) {
1704 err = lpt_init_rd(c);
1705 if (err)
1706 return err;
1707 }
1708
1709 if (wr) {
1710 err = lpt_init_wr(c);
1711 if (err)
1712 return err;
1713 }
1714
1715 return 0;
1716}
1717
1718/**
1719 * struct lpt_scan_node - somewhere to put nodes while we scan LPT.
1720 * @nnode: where to keep a nnode
1721 * @pnode: where to keep a pnode
1722 * @cnode: where to keep a cnode
1723 * @in_tree: is the node in the tree in memory
1724 * @ptr.nnode: pointer to the nnode (if it is an nnode) which may be here or in
1725 * the tree
1726 * @ptr.pnode: ditto for pnode
1727 * @ptr.cnode: ditto for cnode
1728 */
1729struct lpt_scan_node {
1730 union {
1731 struct ubifs_nnode nnode;
1732 struct ubifs_pnode pnode;
1733 struct ubifs_cnode cnode;
1734 };
1735 int in_tree;
1736 union {
1737 struct ubifs_nnode *nnode;
1738 struct ubifs_pnode *pnode;
1739 struct ubifs_cnode *cnode;
1740 } ptr;
1741};
1742
1743/**
1744 * scan_get_nnode - for the scan, get a nnode from either the tree or flash.
1745 * @c: the UBIFS file-system description object
1746 * @path: where to put the nnode
1747 * @parent: parent of the nnode
1748 * @iip: index in parent of the nnode
1749 *
1750 * This function returns a pointer to the nnode on success or a negative error
1751 * code on failure.
1752 */
1753static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
1754 struct lpt_scan_node *path,
1755 struct ubifs_nnode *parent, int iip)
1756{
1757 struct ubifs_nbranch *branch;
1758 struct ubifs_nnode *nnode;
1759 void *buf = c->lpt_nod_buf;
1760 int err;
1761
1762 branch = &parent->nbranch[iip];
1763 nnode = branch->nnode;
1764 if (nnode) {
1765 path->in_tree = 1;
1766 path->ptr.nnode = nnode;
1767 return nnode;
1768 }
1769 nnode = &path->nnode;
1770 path->in_tree = 0;
1771 path->ptr.nnode = nnode;
1772 memset(nnode, 0, sizeof(struct ubifs_nnode));
1773 if (branch->lnum == 0) {
1774 /*
1775 * This nnode was not written which just means that the LEB
1776 * properties in the subtree below it describe empty LEBs. We
1777 * make the nnode as though we had read it, which in fact means
1778 * doing almost nothing.
1779 */
1780 if (c->big_lpt)
1781 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1782 } else {
1783 err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
1784 c->nnode_sz);
1785 if (err)
1786 return ERR_PTR(err);
1787 err = unpack_nnode(c, buf, nnode);
1788 if (err)
1789 return ERR_PTR(err);
1790 }
1791 err = validate_nnode(c, nnode, parent, iip);
1792 if (err)
1793 return ERR_PTR(err);
1794 if (!c->big_lpt)
1795 nnode->num = calc_nnode_num_from_parent(c, parent, iip);
1796 nnode->level = parent->level - 1;
1797 nnode->parent = parent;
1798 nnode->iip = iip;
1799 return nnode;
1800}
1801
1802/**
1803 * scan_get_pnode - for the scan, get a pnode from either the tree or flash.
1804 * @c: the UBIFS file-system description object
1805 * @path: where to put the pnode
1806 * @parent: parent of the pnode
1807 * @iip: index in parent of the pnode
1808 *
1809 * This function returns a pointer to the pnode on success or a negative error
1810 * code on failure.
1811 */
1812static struct ubifs_pnode *scan_get_pnode(struct ubifs_info *c,
1813 struct lpt_scan_node *path,
1814 struct ubifs_nnode *parent, int iip)
1815{
1816 struct ubifs_nbranch *branch;
1817 struct ubifs_pnode *pnode;
1818 void *buf = c->lpt_nod_buf;
1819 int err;
1820
1821 branch = &parent->nbranch[iip];
1822 pnode = branch->pnode;
1823 if (pnode) {
1824 path->in_tree = 1;
1825 path->ptr.pnode = pnode;
1826 return pnode;
1827 }
1828 pnode = &path->pnode;
1829 path->in_tree = 0;
1830 path->ptr.pnode = pnode;
1831 memset(pnode, 0, sizeof(struct ubifs_pnode));
1832 if (branch->lnum == 0) {
1833 /*
1834 * This pnode was not written which just means that the LEB
1835 * properties in it describe empty LEBs. We make the pnode as
1836 * though we had read it.
1837 */
1838 int i;
1839
1840 if (c->big_lpt)
1841 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1842 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
1843 struct ubifs_lprops * const lprops = &pnode->lprops[i];
1844
1845 lprops->free = c->leb_size;
1846 lprops->flags = ubifs_categorize_lprops(c, lprops);
1847 }
1848 } else {
1849 ubifs_assert(branch->lnum >= c->lpt_first &&
1850 branch->lnum <= c->lpt_last);
1851 ubifs_assert(branch->offs >= 0 && branch->offs < c->leb_size);
1852 err = ubi_read(c->ubi, branch->lnum, buf, branch->offs,
1853 c->pnode_sz);
1854 if (err)
1855 return ERR_PTR(err);
1856 err = unpack_pnode(c, buf, pnode);
1857 if (err)
1858 return ERR_PTR(err);
1859 }
1860 err = validate_pnode(c, pnode, parent, iip);
1861 if (err)
1862 return ERR_PTR(err);
1863 if (!c->big_lpt)
1864 pnode->num = calc_pnode_num_from_parent(c, parent, iip);
1865 pnode->parent = parent;
1866 pnode->iip = iip;
1867 set_pnode_lnum(c, pnode);
1868 return pnode;
1869}
1870
1871/**
1872 * ubifs_lpt_scan_nolock - scan the LPT.
1873 * @c: the UBIFS file-system description object
1874 * @start_lnum: LEB number from which to start scanning
1875 * @end_lnum: LEB number at which to stop scanning
1876 * @scan_cb: callback function called for each lprops
1877 * @data: data to be passed to the callback function
1878 *
1879 * This function returns %0 on success and a negative error code on failure.
1880 */
1881int ubifs_lpt_scan_nolock(struct ubifs_info *c, int start_lnum, int end_lnum,
1882 ubifs_lpt_scan_callback scan_cb, void *data)
1883{
1884 int err = 0, i, h, iip, shft;
1885 struct ubifs_nnode *nnode;
1886 struct ubifs_pnode *pnode;
1887 struct lpt_scan_node *path;
1888
1889 if (start_lnum == -1) {
1890 start_lnum = end_lnum + 1;
1891 if (start_lnum >= c->leb_cnt)
1892 start_lnum = c->main_first;
1893 }
1894
1895 ubifs_assert(start_lnum >= c->main_first && start_lnum < c->leb_cnt);
1896 ubifs_assert(end_lnum >= c->main_first && end_lnum < c->leb_cnt);
1897
1898 if (!c->nroot) {
1899 err = ubifs_read_nnode(c, NULL, 0);
1900 if (err)
1901 return err;
1902 }
1903
1904 path = kmalloc(sizeof(struct lpt_scan_node) * (c->lpt_hght + 1),
1905 GFP_NOFS);
1906 if (!path)
1907 return -ENOMEM;
1908
1909 path[0].ptr.nnode = c->nroot;
1910 path[0].in_tree = 1;
1911again:
1912 /* Descend to the pnode containing start_lnum */
1913 nnode = c->nroot;
1914 i = start_lnum - c->main_first;
1915 shft = c->lpt_hght * UBIFS_LPT_FANOUT_SHIFT;
1916 for (h = 1; h < c->lpt_hght; h++) {
1917 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1918 shft -= UBIFS_LPT_FANOUT_SHIFT;
1919 nnode = scan_get_nnode(c, path + h, nnode, iip);
1920 if (IS_ERR(nnode)) {
1921 err = PTR_ERR(nnode);
1922 goto out;
1923 }
1924 }
1925 iip = ((i >> shft) & (UBIFS_LPT_FANOUT - 1));
1926 shft -= UBIFS_LPT_FANOUT_SHIFT;
1927 pnode = scan_get_pnode(c, path + h, nnode, iip);
1928 if (IS_ERR(pnode)) {
1929 err = PTR_ERR(pnode);
1930 goto out;
1931 }
1932 iip = (i & (UBIFS_LPT_FANOUT - 1));
1933
1934 /* Loop for each lprops */
1935 while (1) {
1936 struct ubifs_lprops *lprops = &pnode->lprops[iip];
1937 int ret, lnum = lprops->lnum;
1938
1939 ret = scan_cb(c, lprops, path[h].in_tree, data);
1940 if (ret < 0) {
1941 err = ret;
1942 goto out;
1943 }
1944 if (ret & LPT_SCAN_ADD) {
1945 /* Add all the nodes in path to the tree in memory */
1946 for (h = 1; h < c->lpt_hght; h++) {
1947 const size_t sz = sizeof(struct ubifs_nnode);
1948 struct ubifs_nnode *parent;
1949
1950 if (path[h].in_tree)
1951 continue;
1952 nnode = kmalloc(sz, GFP_NOFS);
1953 if (!nnode) {
1954 err = -ENOMEM;
1955 goto out;
1956 }
1957 memcpy(nnode, &path[h].nnode, sz);
1958 parent = nnode->parent;
1959 parent->nbranch[nnode->iip].nnode = nnode;
1960 path[h].ptr.nnode = nnode;
1961 path[h].in_tree = 1;
1962 path[h + 1].cnode.parent = nnode;
1963 }
1964 if (path[h].in_tree)
1965 ubifs_ensure_cat(c, lprops);
1966 else {
1967 const size_t sz = sizeof(struct ubifs_pnode);
1968 struct ubifs_nnode *parent;
1969
1970 pnode = kmalloc(sz, GFP_NOFS);
1971 if (!pnode) {
1972 err = -ENOMEM;
1973 goto out;
1974 }
1975 memcpy(pnode, &path[h].pnode, sz);
1976 parent = pnode->parent;
1977 parent->nbranch[pnode->iip].pnode = pnode;
1978 path[h].ptr.pnode = pnode;
1979 path[h].in_tree = 1;
1980 update_cats(c, pnode);
1981 c->pnodes_have += 1;
1982 }
1983 err = dbg_check_lpt_nodes(c, (struct ubifs_cnode *)
1984 c->nroot, 0, 0);
1985 if (err)
1986 goto out;
1987 err = dbg_check_cats(c);
1988 if (err)
1989 goto out;
1990 }
1991 if (ret & LPT_SCAN_STOP) {
1992 err = 0;
1993 break;
1994 }
1995 /* Get the next lprops */
1996 if (lnum == end_lnum) {
1997 /*
1998 * We got to the end without finding what we were
1999 * looking for
2000 */
2001 err = -ENOSPC;
2002 goto out;
2003 }
2004 if (lnum + 1 >= c->leb_cnt) {
2005 /* Wrap-around to the beginning */
2006 start_lnum = c->main_first;
2007 goto again;
2008 }
2009 if (iip + 1 < UBIFS_LPT_FANOUT) {
2010 /* Next lprops is in the same pnode */
2011 iip += 1;
2012 continue;
2013 }
2014 /* We need to get the next pnode. Go up until we can go right */
2015 iip = pnode->iip;
2016 while (1) {
2017 h -= 1;
2018 ubifs_assert(h >= 0);
2019 nnode = path[h].ptr.nnode;
2020 if (iip + 1 < UBIFS_LPT_FANOUT)
2021 break;
2022 iip = nnode->iip;
2023 }
2024 /* Go right */
2025 iip += 1;
2026 /* Descend to the pnode */
2027 h += 1;
2028 for (; h < c->lpt_hght; h++) {
2029 nnode = scan_get_nnode(c, path + h, nnode, iip);
2030 if (IS_ERR(nnode)) {
2031 err = PTR_ERR(nnode);
2032 goto out;
2033 }
2034 iip = 0;
2035 }
2036 pnode = scan_get_pnode(c, path + h, nnode, iip);
2037 if (IS_ERR(pnode)) {
2038 err = PTR_ERR(pnode);
2039 goto out;
2040 }
2041 iip = 0;
2042 }
2043out:
2044 kfree(path);
2045 return err;
2046}
2047
2048#ifdef CONFIG_UBIFS_FS_DEBUG
2049
2050/**
2051 * dbg_chk_pnode - check a pnode.
2052 * @c: the UBIFS file-system description object
2053 * @pnode: pnode to check
2054 * @col: pnode column
2055 *
2056 * This function returns %0 on success and a negative error code on failure.
2057 */
2058static int dbg_chk_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
2059 int col)
2060{
2061 int i;
2062
2063 if (pnode->num != col) {
2064 dbg_err("pnode num %d expected %d parent num %d iip %d",
2065 pnode->num, col, pnode->parent->num, pnode->iip);
2066 return -EINVAL;
2067 }
2068 for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
2069 struct ubifs_lprops *lp, *lprops = &pnode->lprops[i];
2070 int lnum = (pnode->num << UBIFS_LPT_FANOUT_SHIFT) + i +
2071 c->main_first;
2072 int found, cat = lprops->flags & LPROPS_CAT_MASK;
2073 struct ubifs_lpt_heap *heap;
2074 struct list_head *list = NULL;
2075
2076 if (lnum >= c->leb_cnt)
2077 continue;
2078 if (lprops->lnum != lnum) {
2079 dbg_err("bad LEB number %d expected %d",
2080 lprops->lnum, lnum);
2081 return -EINVAL;
2082 }
2083 if (lprops->flags & LPROPS_TAKEN) {
2084 if (cat != LPROPS_UNCAT) {
2085 dbg_err("LEB %d taken but not uncat %d",
2086 lprops->lnum, cat);
2087 return -EINVAL;
2088 }
2089 continue;
2090 }
2091 if (lprops->flags & LPROPS_INDEX) {
2092 switch (cat) {
2093 case LPROPS_UNCAT:
2094 case LPROPS_DIRTY_IDX:
2095 case LPROPS_FRDI_IDX:
2096 break;
2097 default:
2098 dbg_err("LEB %d index but cat %d",
2099 lprops->lnum, cat);
2100 return -EINVAL;
2101 }
2102 } else {
2103 switch (cat) {
2104 case LPROPS_UNCAT:
2105 case LPROPS_DIRTY:
2106 case LPROPS_FREE:
2107 case LPROPS_EMPTY:
2108 case LPROPS_FREEABLE:
2109 break;
2110 default:
2111 dbg_err("LEB %d not index but cat %d",
2112 lprops->lnum, cat);
2113 return -EINVAL;
2114 }
2115 }
2116 switch (cat) {
2117 case LPROPS_UNCAT:
2118 list = &c->uncat_list;
2119 break;
2120 case LPROPS_EMPTY:
2121 list = &c->empty_list;
2122 break;
2123 case LPROPS_FREEABLE:
2124 list = &c->freeable_list;
2125 break;
2126 case LPROPS_FRDI_IDX:
2127 list = &c->frdi_idx_list;
2128 break;
2129 }
2130 found = 0;
2131 switch (cat) {
2132 case LPROPS_DIRTY:
2133 case LPROPS_DIRTY_IDX:
2134 case LPROPS_FREE:
2135 heap = &c->lpt_heap[cat - 1];
2136 if (lprops->hpos < heap->cnt &&
2137 heap->arr[lprops->hpos] == lprops)
2138 found = 1;
2139 break;
2140 case LPROPS_UNCAT:
2141 case LPROPS_EMPTY:
2142 case LPROPS_FREEABLE:
2143 case LPROPS_FRDI_IDX:
2144 list_for_each_entry(lp, list, list)
2145 if (lprops == lp) {
2146 found = 1;
2147 break;
2148 }
2149 break;
2150 }
2151 if (!found) {
2152 dbg_err("LEB %d cat %d not found in cat heap/list",
2153 lprops->lnum, cat);
2154 return -EINVAL;
2155 }
2156 switch (cat) {
2157 case LPROPS_EMPTY:
2158 if (lprops->free != c->leb_size) {
2159 dbg_err("LEB %d cat %d free %d dirty %d",
2160 lprops->lnum, cat, lprops->free,
2161 lprops->dirty);
2162 return -EINVAL;
2163 }
2164 case LPROPS_FREEABLE:
2165 case LPROPS_FRDI_IDX:
2166 if (lprops->free + lprops->dirty != c->leb_size) {
2167 dbg_err("LEB %d cat %d free %d dirty %d",
2168 lprops->lnum, cat, lprops->free,
2169 lprops->dirty);
2170 return -EINVAL;
2171 }
2172 }
2173 }
2174 return 0;
2175}
2176
2177/**
2178 * dbg_check_lpt_nodes - check nnodes and pnodes.
2179 * @c: the UBIFS file-system description object
2180 * @cnode: next cnode (nnode or pnode) to check
2181 * @row: row of cnode (root is zero)
2182 * @col: column of cnode (leftmost is zero)
2183 *
2184 * This function returns %0 on success and a negative error code on failure.
2185 */
2186int dbg_check_lpt_nodes(struct ubifs_info *c, struct ubifs_cnode *cnode,
2187 int row, int col)
2188{
2189 struct ubifs_nnode *nnode, *nn;
2190 struct ubifs_cnode *cn;
2191 int num, iip = 0, err;
2192
2193 if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
2194 return 0;
2195
2196 while (cnode) {
2197 ubifs_assert(row >= 0);
2198 nnode = cnode->parent;
2199 if (cnode->level) {
2200 /* cnode is a nnode */
2201 num = calc_nnode_num(row, col);
2202 if (cnode->num != num) {
2203 dbg_err("nnode num %d expected %d "
2204 "parent num %d iip %d", cnode->num, num,
2205 (nnode ? nnode->num : 0), cnode->iip);
2206 return -EINVAL;
2207 }
2208 nn = (struct ubifs_nnode *)cnode;
2209 while (iip < UBIFS_LPT_FANOUT) {
2210 cn = nn->nbranch[iip].cnode;
2211 if (cn) {
2212 /* Go down */
2213 row += 1;
2214 col <<= UBIFS_LPT_FANOUT_SHIFT;
2215 col += iip;
2216 iip = 0;
2217 cnode = cn;
2218 break;
2219 }
2220 /* Go right */
2221 iip += 1;
2222 }
2223 if (iip < UBIFS_LPT_FANOUT)
2224 continue;
2225 } else {
2226 struct ubifs_pnode *pnode;
2227
2228 /* cnode is a pnode */
2229 pnode = (struct ubifs_pnode *)cnode;
2230 err = dbg_chk_pnode(c, pnode, col);
2231 if (err)
2232 return err;
2233 }
2234 /* Go up and to the right */
2235 row -= 1;
2236 col >>= UBIFS_LPT_FANOUT_SHIFT;
2237 iip = cnode->iip + 1;
2238 cnode = (struct ubifs_cnode *)nnode;
2239 }
2240 return 0;
2241}
2242
2243#endif /* CONFIG_UBIFS_FS_DEBUG */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-23 14:18:57 -0500