initial commit with v2.6.9
[linux-2.6.9-moxart.git] / drivers / mtd / nftlmount.c
blobeee7faa5cf110864ec9804a2a2854b6b11f55806
1 /*
2 * NFTL mount code with extensive checks
4 * Author: Fabrice Bellard (fabrice.bellard@netgem.com)
5 * Copyright (C) 2000 Netgem S.A.
7 * $Id: nftlmount.c,v 1.36 2004/06/28 13:52:55 dbrown Exp $
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 #include <linux/kernel.h>
25 #include <asm/errno.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/mtd/mtd.h>
29 #include <linux/mtd/nand.h>
30 #include <linux/mtd/nftl.h>
32 #define SECTORSIZE 512
34 char nftlmountrev[]="$Revision: 1.36 $";
36 /* find_boot_record: Find the NFTL Media Header and its Spare copy which contains the
37 * various device information of the NFTL partition and Bad Unit Table. Update
38 * the ReplUnitTable[] table accroding to the Bad Unit Table. ReplUnitTable[]
39 * is used for management of Erase Unit in other routines in nftl.c and nftlmount.c
41 static int find_boot_record(struct NFTLrecord *nftl)
43 struct nftl_uci1 h1;
44 struct nftl_oob oob;
45 unsigned int block, boot_record_count = 0;
46 size_t retlen;
47 u8 buf[SECTORSIZE];
48 struct NFTLMediaHeader *mh = &nftl->MediaHdr;
49 unsigned int i;
51 /* Assume logical EraseSize == physical erasesize for starting the scan.
52 We'll sort it out later if we find a MediaHeader which says otherwise */
53 /* Actually, we won't. The new DiskOnChip driver has already scanned
54 the MediaHeader and adjusted the virtual erasesize it presents in
55 the mtd device accordingly. We could even get rid of
56 nftl->EraseSize if there were any point in doing so. */
57 nftl->EraseSize = nftl->mbd.mtd->erasesize;
58 nftl->nb_blocks = nftl->mbd.mtd->size / nftl->EraseSize;
60 nftl->MediaUnit = BLOCK_NIL;
61 nftl->SpareMediaUnit = BLOCK_NIL;
63 /* search for a valid boot record */
64 for (block = 0; block < nftl->nb_blocks; block++) {
65 int ret;
67 /* Check for ANAND header first. Then can whinge if it's found but later
68 checks fail */
69 ret = MTD_READ(nftl->mbd.mtd, block * nftl->EraseSize, SECTORSIZE, &retlen, buf);
70 /* We ignore ret in case the ECC of the MediaHeader is invalid
71 (which is apparently acceptable) */
72 if (retlen != SECTORSIZE) {
73 static int warncount = 5;
75 if (warncount) {
76 printk(KERN_WARNING "Block read at 0x%x of mtd%d failed: %d\n",
77 block * nftl->EraseSize, nftl->mbd.mtd->index, ret);
78 if (!--warncount)
79 printk(KERN_WARNING "Further failures for this block will not be printed\n");
81 continue;
84 if (retlen < 6 || memcmp(buf, "ANAND", 6)) {
85 /* ANAND\0 not found. Continue */
86 #if 0
87 printk(KERN_DEBUG "ANAND header not found at 0x%x in mtd%d\n",
88 block * nftl->EraseSize, nftl->mbd.mtd->index);
89 #endif
90 continue;
93 /* To be safer with BIOS, also use erase mark as discriminant */
94 if ((ret = MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + SECTORSIZE + 8,
95 8, &retlen, (char *)&h1) < 0)) {
96 printk(KERN_WARNING "ANAND header found at 0x%x in mtd%d, but OOB data read failed (err %d)\n",
97 block * nftl->EraseSize, nftl->mbd.mtd->index, ret);
98 continue;
101 #if 0 /* Some people seem to have devices without ECC or erase marks
102 on the Media Header blocks. There are enough other sanity
103 checks in here that we can probably do without it.
105 if (le16_to_cpu(h1.EraseMark | h1.EraseMark1) != ERASE_MARK) {
106 printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but erase mark not present (0x%04x,0x%04x instead)\n",
107 block * nftl->EraseSize, nftl->mbd.mtd->index,
108 le16_to_cpu(h1.EraseMark), le16_to_cpu(h1.EraseMark1));
109 continue;
112 /* Finally reread to check ECC */
113 if ((ret = MTD_READECC(nftl->mbd.mtd, block * nftl->EraseSize, SECTORSIZE,
114 &retlen, buf, (char *)&oob, NULL) < 0)) {
115 printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but ECC read failed (err %d)\n",
116 block * nftl->EraseSize, nftl->mbd.mtd->index, ret);
117 continue;
120 /* Paranoia. Check the ANAND header is still there after the ECC read */
121 if (memcmp(buf, "ANAND", 6)) {
122 printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but went away on reread!\n",
123 block * nftl->EraseSize, nftl->mbd.mtd->index);
124 printk(KERN_NOTICE "New data are: %02x %02x %02x %02x %02x %02x\n",
125 buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]);
126 continue;
128 #endif
129 /* OK, we like it. */
131 if (boot_record_count) {
132 /* We've already processed one. So we just check if
133 this one is the same as the first one we found */
134 if (memcmp(mh, buf, sizeof(struct NFTLMediaHeader))) {
135 printk(KERN_NOTICE "NFTL Media Headers at 0x%x and 0x%x disagree.\n",
136 nftl->MediaUnit * nftl->EraseSize, block * nftl->EraseSize);
137 /* if (debug) Print both side by side */
138 if (boot_record_count < 2) {
139 /* We haven't yet seen two real ones */
140 return -1;
142 continue;
144 if (boot_record_count == 1)
145 nftl->SpareMediaUnit = block;
147 /* Mark this boot record (NFTL MediaHeader) block as reserved */
148 nftl->ReplUnitTable[block] = BLOCK_RESERVED;
151 boot_record_count++;
152 continue;
155 /* This is the first we've seen. Copy the media header structure into place */
156 memcpy(mh, buf, sizeof(struct NFTLMediaHeader));
158 /* Do some sanity checks on it */
159 #if 0
160 The new DiskOnChip driver scans the MediaHeader itself, and presents a virtual
161 erasesize based on UnitSizeFactor. So the erasesize we read from the mtd
162 device is already correct.
163 if (mh->UnitSizeFactor == 0) {
164 printk(KERN_NOTICE "NFTL: UnitSizeFactor 0x00 detected. This violates the spec but we think we know what it means...\n");
165 } else if (mh->UnitSizeFactor < 0xfc) {
166 printk(KERN_NOTICE "Sorry, we don't support UnitSizeFactor 0x%02x\n",
167 mh->UnitSizeFactor);
168 return -1;
169 } else if (mh->UnitSizeFactor != 0xff) {
170 printk(KERN_NOTICE "WARNING: Support for NFTL with UnitSizeFactor 0x%02x is experimental\n",
171 mh->UnitSizeFactor);
172 nftl->EraseSize = nftl->mbd.mtd->erasesize << (0xff - mh->UnitSizeFactor);
173 nftl->nb_blocks = nftl->mbd.mtd->size / nftl->EraseSize;
175 #endif
176 nftl->nb_boot_blocks = le16_to_cpu(mh->FirstPhysicalEUN);
177 if ((nftl->nb_boot_blocks + 2) >= nftl->nb_blocks) {
178 printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n");
179 printk(KERN_NOTICE "nb_boot_blocks (%d) + 2 > nb_blocks (%d)\n",
180 nftl->nb_boot_blocks, nftl->nb_blocks);
181 return -1;
184 nftl->numvunits = le32_to_cpu(mh->FormattedSize) / nftl->EraseSize;
185 if (nftl->numvunits > (nftl->nb_blocks - nftl->nb_boot_blocks - 2)) {
186 printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n");
187 printk(KERN_NOTICE "numvunits (%d) > nb_blocks (%d) - nb_boot_blocks(%d) - 2\n",
188 nftl->numvunits, nftl->nb_blocks, nftl->nb_boot_blocks);
189 return -1;
192 nftl->mbd.size = nftl->numvunits * (nftl->EraseSize / SECTORSIZE);
194 /* If we're not using the last sectors in the device for some reason,
195 reduce nb_blocks accordingly so we forget they're there */
196 nftl->nb_blocks = le16_to_cpu(mh->NumEraseUnits) + le16_to_cpu(mh->FirstPhysicalEUN);
198 /* XXX: will be suppressed */
199 nftl->lastEUN = nftl->nb_blocks - 1;
201 /* memory alloc */
202 nftl->EUNtable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL);
203 if (!nftl->EUNtable) {
204 printk(KERN_NOTICE "NFTL: allocation of EUNtable failed\n");
205 return -ENOMEM;
208 nftl->ReplUnitTable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL);
209 if (!nftl->ReplUnitTable) {
210 kfree(nftl->EUNtable);
211 printk(KERN_NOTICE "NFTL: allocation of ReplUnitTable failed\n");
212 return -ENOMEM;
215 /* mark the bios blocks (blocks before NFTL MediaHeader) as reserved */
216 for (i = 0; i < nftl->nb_boot_blocks; i++)
217 nftl->ReplUnitTable[i] = BLOCK_RESERVED;
218 /* mark all remaining blocks as potentially containing data */
219 for (; i < nftl->nb_blocks; i++) {
220 nftl->ReplUnitTable[i] = BLOCK_NOTEXPLORED;
223 /* Mark this boot record (NFTL MediaHeader) block as reserved */
224 nftl->ReplUnitTable[block] = BLOCK_RESERVED;
226 /* read the Bad Erase Unit Table and modify ReplUnitTable[] accordingly */
227 for (i = 0; i < nftl->nb_blocks; i++) {
228 #if 0
229 The new DiskOnChip driver already scanned the bad block table. Just query it.
230 if ((i & (SECTORSIZE - 1)) == 0) {
231 /* read one sector for every SECTORSIZE of blocks */
232 if ((ret = MTD_READECC(nftl->mbd.mtd, block * nftl->EraseSize +
233 i + SECTORSIZE, SECTORSIZE, &retlen, buf,
234 (char *)&oob, NULL)) < 0) {
235 printk(KERN_NOTICE "Read of bad sector table failed (err %d)\n",
236 ret);
237 kfree(nftl->ReplUnitTable);
238 kfree(nftl->EUNtable);
239 return -1;
242 /* mark the Bad Erase Unit as RESERVED in ReplUnitTable */
243 if (buf[i & (SECTORSIZE - 1)] != 0xff)
244 nftl->ReplUnitTable[i] = BLOCK_RESERVED;
245 #endif
246 if (nftl->mbd.mtd->block_isbad(nftl->mbd.mtd, i * nftl->EraseSize))
247 nftl->ReplUnitTable[i] = BLOCK_RESERVED;
250 nftl->MediaUnit = block;
251 boot_record_count++;
253 } /* foreach (block) */
255 return boot_record_count?0:-1;
258 static int memcmpb(void *a, int c, int n)
260 int i;
261 for (i = 0; i < n; i++) {
262 if (c != ((unsigned char *)a)[i])
263 return 1;
265 return 0;
268 /* check_free_sector: check if a free sector is actually FREE, i.e. All 0xff in data and oob area */
269 static int check_free_sectors(struct NFTLrecord *nftl, unsigned int address, int len,
270 int check_oob)
272 int i;
273 size_t retlen;
274 u8 buf[SECTORSIZE + nftl->mbd.mtd->oobsize];
276 for (i = 0; i < len; i += SECTORSIZE) {
277 if (MTD_READECC(nftl->mbd.mtd, address, SECTORSIZE, &retlen, buf, &buf[SECTORSIZE], &nftl->oobinfo) < 0)
278 return -1;
279 if (memcmpb(buf, 0xff, SECTORSIZE) != 0)
280 return -1;
282 if (check_oob) {
283 if (memcmpb(buf + SECTORSIZE, 0xff, nftl->mbd.mtd->oobsize) != 0)
284 return -1;
286 address += SECTORSIZE;
289 return 0;
292 /* NFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase Unit and
293 * Update NFTL metadata. Each erase operation is checked with check_free_sectors
295 * Return: 0 when succeed, -1 on error.
297 * ToDo: 1. Is it neceressary to check_free_sector after erasing ??
299 int NFTL_formatblock(struct NFTLrecord *nftl, int block)
301 size_t retlen;
302 unsigned int nb_erases, erase_mark;
303 struct nftl_uci1 uci;
304 struct erase_info *instr = &nftl->instr;
306 /* Read the Unit Control Information #1 for Wear-Leveling */
307 if (MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + SECTORSIZE + 8,
308 8, &retlen, (char *)&uci) < 0)
309 goto default_uci1;
311 erase_mark = le16_to_cpu ((uci.EraseMark | uci.EraseMark1));
312 if (erase_mark != ERASE_MARK) {
313 default_uci1:
314 uci.EraseMark = cpu_to_le16(ERASE_MARK);
315 uci.EraseMark1 = cpu_to_le16(ERASE_MARK);
316 uci.WearInfo = cpu_to_le32(0);
319 memset(instr, 0, sizeof(struct erase_info));
321 /* XXX: use async erase interface, XXX: test return code */
322 instr->addr = block * nftl->EraseSize;
323 instr->len = nftl->EraseSize;
324 MTD_ERASE(nftl->mbd.mtd, instr);
326 if (instr->state == MTD_ERASE_FAILED) {
327 printk("Error while formatting block %d\n", block);
328 goto fail;
331 /* increase and write Wear-Leveling info */
332 nb_erases = le32_to_cpu(uci.WearInfo);
333 nb_erases++;
335 /* wrap (almost impossible with current flashs) or free block */
336 if (nb_erases == 0)
337 nb_erases = 1;
339 /* check the "freeness" of Erase Unit before updating metadata
340 * FixMe: is this check really necessary ? since we have check the
341 * return code after the erase operation. */
342 if (check_free_sectors(nftl, instr->addr, nftl->EraseSize, 1) != 0)
343 goto fail;
345 uci.WearInfo = le32_to_cpu(nb_erases);
346 if (MTD_WRITEOOB(nftl->mbd.mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8,
347 &retlen, (char *)&uci) < 0)
348 goto fail;
349 return 0;
350 fail:
351 /* could not format, update the bad block table (caller is responsible
352 for setting the ReplUnitTable to BLOCK_RESERVED on failure) */
353 nftl->mbd.mtd->block_markbad(nftl->mbd.mtd, instr->addr);
354 return -1;
357 /* check_sectors_in_chain: Check that each sector of a Virtual Unit Chain is correct.
358 * Mark as 'IGNORE' each incorrect sector. This check is only done if the chain
359 * was being folded when NFTL was interrupted.
361 * The check_free_sectors in this function is neceressary. There is a possible
362 * situation that after writing the Data area, the Block Control Information is
363 * not updated according (due to power failure or something) which leaves the block
364 * in an umconsistent state. So we have to check if a block is really FREE in this
365 * case. */
366 static void check_sectors_in_chain(struct NFTLrecord *nftl, unsigned int first_block)
368 unsigned int block, i, status;
369 struct nftl_bci bci;
370 int sectors_per_block;
371 size_t retlen;
373 sectors_per_block = nftl->EraseSize / SECTORSIZE;
374 block = first_block;
375 for (;;) {
376 for (i = 0; i < sectors_per_block; i++) {
377 if (MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + i * SECTORSIZE,
378 8, &retlen, (char *)&bci) < 0)
379 status = SECTOR_IGNORE;
380 else
381 status = bci.Status | bci.Status1;
383 switch(status) {
384 case SECTOR_FREE:
385 /* verify that the sector is really free. If not, mark
386 as ignore */
387 if (memcmpb(&bci, 0xff, 8) != 0 ||
388 check_free_sectors(nftl, block * nftl->EraseSize + i * SECTORSIZE,
389 SECTORSIZE, 0) != 0) {
390 printk("Incorrect free sector %d in block %d: "
391 "marking it as ignored\n",
392 i, block);
394 /* sector not free actually : mark it as SECTOR_IGNORE */
395 bci.Status = SECTOR_IGNORE;
396 bci.Status1 = SECTOR_IGNORE;
397 MTD_WRITEOOB(nftl->mbd.mtd,
398 block * nftl->EraseSize + i * SECTORSIZE,
399 8, &retlen, (char *)&bci);
401 break;
402 default:
403 break;
407 /* proceed to next Erase Unit on the chain */
408 block = nftl->ReplUnitTable[block];
409 if (!(block == BLOCK_NIL || block < nftl->nb_blocks))
410 printk("incorrect ReplUnitTable[] : %d\n", block);
411 if (block == BLOCK_NIL || block >= nftl->nb_blocks)
412 break;
416 /* calc_chain_lenght: Walk through a Virtual Unit Chain and estimate chain length */
417 static int calc_chain_length(struct NFTLrecord *nftl, unsigned int first_block)
419 unsigned int length = 0, block = first_block;
421 for (;;) {
422 length++;
423 /* avoid infinite loops, although this is guaranted not to
424 happen because of the previous checks */
425 if (length >= nftl->nb_blocks) {
426 printk("nftl: length too long %d !\n", length);
427 break;
430 block = nftl->ReplUnitTable[block];
431 if (!(block == BLOCK_NIL || block < nftl->nb_blocks))
432 printk("incorrect ReplUnitTable[] : %d\n", block);
433 if (block == BLOCK_NIL || block >= nftl->nb_blocks)
434 break;
436 return length;
439 /* format_chain: Format an invalid Virtual Unit chain. It frees all the Erase Units in a
440 * Virtual Unit Chain, i.e. all the units are disconnected.
442 * It is not stricly correct to begin from the first block of the chain because
443 * if we stop the code, we may see again a valid chain if there was a first_block
444 * flag in a block inside it. But is it really a problem ?
446 * FixMe: Figure out what the last statesment means. What if power failure when we are
447 * in the for (;;) loop formatting blocks ??
449 static void format_chain(struct NFTLrecord *nftl, unsigned int first_block)
451 unsigned int block = first_block, block1;
453 printk("Formatting chain at block %d\n", first_block);
455 for (;;) {
456 block1 = nftl->ReplUnitTable[block];
458 printk("Formatting block %d\n", block);
459 if (NFTL_formatblock(nftl, block) < 0) {
460 /* cannot format !!!! Mark it as Bad Unit */
461 nftl->ReplUnitTable[block] = BLOCK_RESERVED;
462 } else {
463 nftl->ReplUnitTable[block] = BLOCK_FREE;
466 /* goto next block on the chain */
467 block = block1;
469 if (!(block == BLOCK_NIL || block < nftl->nb_blocks))
470 printk("incorrect ReplUnitTable[] : %d\n", block);
471 if (block == BLOCK_NIL || block >= nftl->nb_blocks)
472 break;
476 /* check_and_mark_free_block: Verify that a block is free in the NFTL sense (valid erase mark) or
477 * totally free (only 0xff).
479 * Definition: Free Erase Unit -- A properly erased/formatted Free Erase Unit should have meet the
480 * following critia:
481 * 1. */
482 static int check_and_mark_free_block(struct NFTLrecord *nftl, int block)
484 struct nftl_uci1 h1;
485 unsigned int erase_mark;
486 size_t retlen;
488 /* check erase mark. */
489 if (MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8,
490 &retlen, (char *)&h1) < 0)
491 return -1;
493 erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1));
494 if (erase_mark != ERASE_MARK) {
495 /* if no erase mark, the block must be totally free. This is
496 possible in two cases : empty filsystem or interrupted erase (very unlikely) */
497 if (check_free_sectors (nftl, block * nftl->EraseSize, nftl->EraseSize, 1) != 0)
498 return -1;
500 /* free block : write erase mark */
501 h1.EraseMark = cpu_to_le16(ERASE_MARK);
502 h1.EraseMark1 = cpu_to_le16(ERASE_MARK);
503 h1.WearInfo = cpu_to_le32(0);
504 if (MTD_WRITEOOB(nftl->mbd.mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8,
505 &retlen, (char *)&h1) < 0)
506 return -1;
507 } else {
508 #if 0
509 /* if erase mark present, need to skip it when doing check */
510 for (i = 0; i < nftl->EraseSize; i += SECTORSIZE) {
511 /* check free sector */
512 if (check_free_sectors (nftl, block * nftl->EraseSize + i,
513 SECTORSIZE, 0) != 0)
514 return -1;
516 if (MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + i,
517 16, &retlen, buf) < 0)
518 return -1;
519 if (i == SECTORSIZE) {
520 /* skip erase mark */
521 if (memcmpb(buf, 0xff, 8))
522 return -1;
523 } else {
524 if (memcmpb(buf, 0xff, 16))
525 return -1;
528 #endif
531 return 0;
534 /* get_fold_mark: Read fold mark from Unit Control Information #2, we use FOLD_MARK_IN_PROGRESS
535 * to indicate that we are in the progression of a Virtual Unit Chain folding. If the UCI #2
536 * is FOLD_MARK_IN_PROGRESS when mounting the NFTL, the (previous) folding process is interrupted
537 * for some reason. A clean up/check of the VUC is neceressary in this case.
539 * WARNING: return 0 if read error
541 static int get_fold_mark(struct NFTLrecord *nftl, unsigned int block)
543 struct nftl_uci2 uci;
544 size_t retlen;
546 if (MTD_READOOB(nftl->mbd.mtd, block * nftl->EraseSize + 2 * SECTORSIZE + 8,
547 8, &retlen, (char *)&uci) < 0)
548 return 0;
550 return le16_to_cpu((uci.FoldMark | uci.FoldMark1));
553 int NFTL_mount(struct NFTLrecord *s)
555 int i;
556 unsigned int first_logical_block, logical_block, rep_block, nb_erases, erase_mark;
557 unsigned int block, first_block, is_first_block;
558 int chain_length, do_format_chain;
559 struct nftl_uci0 h0;
560 struct nftl_uci1 h1;
561 size_t retlen;
563 /* search for NFTL MediaHeader and Spare NFTL Media Header */
564 if (find_boot_record(s) < 0) {
565 printk("Could not find valid boot record\n");
566 return -1;
569 /* init the logical to physical table */
570 for (i = 0; i < s->nb_blocks; i++) {
571 s->EUNtable[i] = BLOCK_NIL;
574 /* first pass : explore each block chain */
575 first_logical_block = 0;
576 for (first_block = 0; first_block < s->nb_blocks; first_block++) {
577 /* if the block was not already explored, we can look at it */
578 if (s->ReplUnitTable[first_block] == BLOCK_NOTEXPLORED) {
579 block = first_block;
580 chain_length = 0;
581 do_format_chain = 0;
583 for (;;) {
584 /* read the block header. If error, we format the chain */
585 if (MTD_READOOB(s->mbd.mtd, block * s->EraseSize + 8, 8,
586 &retlen, (char *)&h0) < 0 ||
587 MTD_READOOB(s->mbd.mtd, block * s->EraseSize + SECTORSIZE + 8, 8,
588 &retlen, (char *)&h1) < 0) {
589 s->ReplUnitTable[block] = BLOCK_NIL;
590 do_format_chain = 1;
591 break;
594 logical_block = le16_to_cpu ((h0.VirtUnitNum | h0.SpareVirtUnitNum));
595 rep_block = le16_to_cpu ((h0.ReplUnitNum | h0.SpareReplUnitNum));
596 nb_erases = le32_to_cpu (h1.WearInfo);
597 erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1));
599 is_first_block = !(logical_block >> 15);
600 logical_block = logical_block & 0x7fff;
602 /* invalid/free block test */
603 if (erase_mark != ERASE_MARK || logical_block >= s->nb_blocks) {
604 if (chain_length == 0) {
605 /* if not currently in a chain, we can handle it safely */
606 if (check_and_mark_free_block(s, block) < 0) {
607 /* not really free: format it */
608 printk("Formatting block %d\n", block);
609 if (NFTL_formatblock(s, block) < 0) {
610 /* could not format: reserve the block */
611 s->ReplUnitTable[block] = BLOCK_RESERVED;
612 } else {
613 s->ReplUnitTable[block] = BLOCK_FREE;
615 } else {
616 /* free block: mark it */
617 s->ReplUnitTable[block] = BLOCK_FREE;
619 /* directly examine the next block. */
620 goto examine_ReplUnitTable;
621 } else {
622 /* the block was in a chain : this is bad. We
623 must format all the chain */
624 printk("Block %d: free but referenced in chain %d\n",
625 block, first_block);
626 s->ReplUnitTable[block] = BLOCK_NIL;
627 do_format_chain = 1;
628 break;
632 /* we accept only first blocks here */
633 if (chain_length == 0) {
634 /* this block is not the first block in chain :
635 ignore it, it will be included in a chain
636 later, or marked as not explored */
637 if (!is_first_block)
638 goto examine_ReplUnitTable;
639 first_logical_block = logical_block;
640 } else {
641 if (logical_block != first_logical_block) {
642 printk("Block %d: incorrect logical block: %d expected: %d\n",
643 block, logical_block, first_logical_block);
644 /* the chain is incorrect : we must format it,
645 but we need to read it completly */
646 do_format_chain = 1;
648 if (is_first_block) {
649 /* we accept that a block is marked as first
650 block while being last block in a chain
651 only if the chain is being folded */
652 if (get_fold_mark(s, block) != FOLD_MARK_IN_PROGRESS ||
653 rep_block != 0xffff) {
654 printk("Block %d: incorrectly marked as first block in chain\n",
655 block);
656 /* the chain is incorrect : we must format it,
657 but we need to read it completly */
658 do_format_chain = 1;
659 } else {
660 printk("Block %d: folding in progress - ignoring first block flag\n",
661 block);
665 chain_length++;
666 if (rep_block == 0xffff) {
667 /* no more blocks after */
668 s->ReplUnitTable[block] = BLOCK_NIL;
669 break;
670 } else if (rep_block >= s->nb_blocks) {
671 printk("Block %d: referencing invalid block %d\n",
672 block, rep_block);
673 do_format_chain = 1;
674 s->ReplUnitTable[block] = BLOCK_NIL;
675 break;
676 } else if (s->ReplUnitTable[rep_block] != BLOCK_NOTEXPLORED) {
677 /* same problem as previous 'is_first_block' test:
678 we accept that the last block of a chain has
679 the first_block flag set if folding is in
680 progress. We handle here the case where the
681 last block appeared first */
682 if (s->ReplUnitTable[rep_block] == BLOCK_NIL &&
683 s->EUNtable[first_logical_block] == rep_block &&
684 get_fold_mark(s, first_block) == FOLD_MARK_IN_PROGRESS) {
685 /* EUNtable[] will be set after */
686 printk("Block %d: folding in progress - ignoring first block flag\n",
687 rep_block);
688 s->ReplUnitTable[block] = rep_block;
689 s->EUNtable[first_logical_block] = BLOCK_NIL;
690 } else {
691 printk("Block %d: referencing block %d already in another chain\n",
692 block, rep_block);
693 /* XXX: should handle correctly fold in progress chains */
694 do_format_chain = 1;
695 s->ReplUnitTable[block] = BLOCK_NIL;
697 break;
698 } else {
699 /* this is OK */
700 s->ReplUnitTable[block] = rep_block;
701 block = rep_block;
705 /* the chain was completely explored. Now we can decide
706 what to do with it */
707 if (do_format_chain) {
708 /* invalid chain : format it */
709 format_chain(s, first_block);
710 } else {
711 unsigned int first_block1, chain_to_format, chain_length1;
712 int fold_mark;
714 /* valid chain : get foldmark */
715 fold_mark = get_fold_mark(s, first_block);
716 if (fold_mark == 0) {
717 /* cannot get foldmark : format the chain */
718 printk("Could read foldmark at block %d\n", first_block);
719 format_chain(s, first_block);
720 } else {
721 if (fold_mark == FOLD_MARK_IN_PROGRESS)
722 check_sectors_in_chain(s, first_block);
724 /* now handle the case where we find two chains at the
725 same virtual address : we select the longer one,
726 because the shorter one is the one which was being
727 folded if the folding was not done in place */
728 first_block1 = s->EUNtable[first_logical_block];
729 if (first_block1 != BLOCK_NIL) {
730 /* XXX: what to do if same length ? */
731 chain_length1 = calc_chain_length(s, first_block1);
732 printk("Two chains at blocks %d (len=%d) and %d (len=%d)\n",
733 first_block1, chain_length1, first_block, chain_length);
735 if (chain_length >= chain_length1) {
736 chain_to_format = first_block1;
737 s->EUNtable[first_logical_block] = first_block;
738 } else {
739 chain_to_format = first_block;
741 format_chain(s, chain_to_format);
742 } else {
743 s->EUNtable[first_logical_block] = first_block;
748 examine_ReplUnitTable:;
751 /* second pass to format unreferenced blocks and init free block count */
752 s->numfreeEUNs = 0;
753 s->LastFreeEUN = le16_to_cpu(s->MediaHdr.FirstPhysicalEUN);
755 for (block = 0; block < s->nb_blocks; block++) {
756 if (s->ReplUnitTable[block] == BLOCK_NOTEXPLORED) {
757 printk("Unreferenced block %d, formatting it\n", block);
758 if (NFTL_formatblock(s, block) < 0)
759 s->ReplUnitTable[block] = BLOCK_RESERVED;
760 else
761 s->ReplUnitTable[block] = BLOCK_FREE;
763 if (s->ReplUnitTable[block] == BLOCK_FREE) {
764 s->numfreeEUNs++;
765 s->LastFreeEUN = block;
769 return 0;