]>
Commit | Line | Data |
---|---|---|
97894cda | 1 | /* |
1da177e4 LT |
2 | * NFTL mount code with extensive checks |
3 | * | |
97894cda | 4 | * Author: Fabrice Bellard (fabrice.bellard@netgem.com) |
a1452a37 DW |
5 | * Copyright © 2000 Netgem S.A. |
6 | * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> | |
1da177e4 | 7 | * |
1da177e4 LT |
8 | * This program is free software; you can redistribute it and/or modify |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | */ | |
22 | ||
23 | #include <linux/kernel.h> | |
24 | #include <asm/errno.h> | |
25 | #include <linux/delay.h> | |
26 | #include <linux/slab.h> | |
27 | #include <linux/mtd/mtd.h> | |
28 | #include <linux/mtd/nand.h> | |
29 | #include <linux/mtd/nftl.h> | |
30 | ||
31 | #define SECTORSIZE 512 | |
32 | ||
1da177e4 LT |
33 | /* find_boot_record: Find the NFTL Media Header and its Spare copy which contains the |
34 | * various device information of the NFTL partition and Bad Unit Table. Update | |
35 | * the ReplUnitTable[] table accroding to the Bad Unit Table. ReplUnitTable[] | |
36 | * is used for management of Erase Unit in other routines in nftl.c and nftlmount.c | |
37 | */ | |
38 | static int find_boot_record(struct NFTLrecord *nftl) | |
39 | { | |
40 | struct nftl_uci1 h1; | |
41 | unsigned int block, boot_record_count = 0; | |
42 | size_t retlen; | |
43 | u8 buf[SECTORSIZE]; | |
44 | struct NFTLMediaHeader *mh = &nftl->MediaHdr; | |
f4a43cfc | 45 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
46 | unsigned int i; |
47 | ||
97894cda | 48 | /* Assume logical EraseSize == physical erasesize for starting the scan. |
1da177e4 LT |
49 | We'll sort it out later if we find a MediaHeader which says otherwise */ |
50 | /* Actually, we won't. The new DiskOnChip driver has already scanned | |
51 | the MediaHeader and adjusted the virtual erasesize it presents in | |
52 | the mtd device accordingly. We could even get rid of | |
53 | nftl->EraseSize if there were any point in doing so. */ | |
54 | nftl->EraseSize = nftl->mbd.mtd->erasesize; | |
69423d99 | 55 | nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize; |
1da177e4 LT |
56 | |
57 | nftl->MediaUnit = BLOCK_NIL; | |
58 | nftl->SpareMediaUnit = BLOCK_NIL; | |
59 | ||
60 | /* search for a valid boot record */ | |
61 | for (block = 0; block < nftl->nb_blocks; block++) { | |
62 | int ret; | |
63 | ||
64 | /* Check for ANAND header first. Then can whinge if it's found but later | |
65 | checks fail */ | |
f4a43cfc TG |
66 | ret = mtd->read(mtd, block * nftl->EraseSize, SECTORSIZE, |
67 | &retlen, buf); | |
1da177e4 LT |
68 | /* We ignore ret in case the ECC of the MediaHeader is invalid |
69 | (which is apparently acceptable) */ | |
70 | if (retlen != SECTORSIZE) { | |
71 | static int warncount = 5; | |
72 | ||
73 | if (warncount) { | |
74 | printk(KERN_WARNING "Block read at 0x%x of mtd%d failed: %d\n", | |
75 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
76 | if (!--warncount) | |
77 | printk(KERN_WARNING "Further failures for this block will not be printed\n"); | |
78 | } | |
79 | continue; | |
80 | } | |
81 | ||
82 | if (retlen < 6 || memcmp(buf, "ANAND", 6)) { | |
83 | /* ANAND\0 not found. Continue */ | |
84 | #if 0 | |
97894cda | 85 | printk(KERN_DEBUG "ANAND header not found at 0x%x in mtd%d\n", |
1da177e4 | 86 | block * nftl->EraseSize, nftl->mbd.mtd->index); |
97894cda | 87 | #endif |
1da177e4 LT |
88 | continue; |
89 | } | |
90 | ||
91 | /* To be safer with BIOS, also use erase mark as discriminant */ | |
8593fbc6 | 92 | if ((ret = nftl_read_oob(mtd, block * nftl->EraseSize + |
f4a43cfc TG |
93 | SECTORSIZE + 8, 8, &retlen, |
94 | (char *)&h1) < 0)) { | |
1da177e4 LT |
95 | printk(KERN_WARNING "ANAND header found at 0x%x in mtd%d, but OOB data read failed (err %d)\n", |
96 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
97 | continue; | |
98 | } | |
99 | ||
100 | #if 0 /* Some people seem to have devices without ECC or erase marks | |
101 | on the Media Header blocks. There are enough other sanity | |
102 | checks in here that we can probably do without it. | |
103 | */ | |
104 | if (le16_to_cpu(h1.EraseMark | h1.EraseMark1) != ERASE_MARK) { | |
105 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but erase mark not present (0x%04x,0x%04x instead)\n", | |
97894cda | 106 | block * nftl->EraseSize, nftl->mbd.mtd->index, |
1da177e4 LT |
107 | le16_to_cpu(h1.EraseMark), le16_to_cpu(h1.EraseMark1)); |
108 | continue; | |
109 | } | |
110 | ||
111 | /* Finally reread to check ECC */ | |
f4a43cfc TG |
112 | if ((ret = mtd->read(mtd, block * nftl->EraseSize, SECTORSIZE, |
113 | &retlen, buf) < 0)) { | |
1da177e4 LT |
114 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but ECC read failed (err %d)\n", |
115 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
116 | continue; | |
117 | } | |
118 | ||
119 | /* Paranoia. Check the ANAND header is still there after the ECC read */ | |
120 | if (memcmp(buf, "ANAND", 6)) { | |
121 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but went away on reread!\n", | |
122 | block * nftl->EraseSize, nftl->mbd.mtd->index); | |
123 | printk(KERN_NOTICE "New data are: %02x %02x %02x %02x %02x %02x\n", | |
124 | buf[0], buf[1], buf[2], buf[3], buf[4], buf[5]); | |
125 | continue; | |
126 | } | |
127 | #endif | |
128 | /* OK, we like it. */ | |
129 | ||
130 | if (boot_record_count) { | |
131 | /* We've already processed one. So we just check if | |
132 | this one is the same as the first one we found */ | |
133 | if (memcmp(mh, buf, sizeof(struct NFTLMediaHeader))) { | |
134 | printk(KERN_NOTICE "NFTL Media Headers at 0x%x and 0x%x disagree.\n", | |
135 | nftl->MediaUnit * nftl->EraseSize, block * nftl->EraseSize); | |
136 | /* if (debug) Print both side by side */ | |
137 | if (boot_record_count < 2) { | |
138 | /* We haven't yet seen two real ones */ | |
139 | return -1; | |
140 | } | |
141 | continue; | |
142 | } | |
143 | if (boot_record_count == 1) | |
144 | nftl->SpareMediaUnit = block; | |
145 | ||
146 | /* Mark this boot record (NFTL MediaHeader) block as reserved */ | |
147 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
148 | ||
149 | ||
150 | boot_record_count++; | |
151 | continue; | |
152 | } | |
153 | ||
154 | /* This is the first we've seen. Copy the media header structure into place */ | |
155 | memcpy(mh, buf, sizeof(struct NFTLMediaHeader)); | |
156 | ||
157 | /* Do some sanity checks on it */ | |
158 | #if 0 | |
159 | The new DiskOnChip driver scans the MediaHeader itself, and presents a virtual | |
160 | erasesize based on UnitSizeFactor. So the erasesize we read from the mtd | |
161 | device is already correct. | |
162 | if (mh->UnitSizeFactor == 0) { | |
163 | printk(KERN_NOTICE "NFTL: UnitSizeFactor 0x00 detected. This violates the spec but we think we know what it means...\n"); | |
164 | } else if (mh->UnitSizeFactor < 0xfc) { | |
165 | printk(KERN_NOTICE "Sorry, we don't support UnitSizeFactor 0x%02x\n", | |
166 | mh->UnitSizeFactor); | |
167 | return -1; | |
168 | } else if (mh->UnitSizeFactor != 0xff) { | |
169 | printk(KERN_NOTICE "WARNING: Support for NFTL with UnitSizeFactor 0x%02x is experimental\n", | |
170 | mh->UnitSizeFactor); | |
171 | nftl->EraseSize = nftl->mbd.mtd->erasesize << (0xff - mh->UnitSizeFactor); | |
69423d99 | 172 | nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize; |
1da177e4 LT |
173 | } |
174 | #endif | |
175 | nftl->nb_boot_blocks = le16_to_cpu(mh->FirstPhysicalEUN); | |
176 | if ((nftl->nb_boot_blocks + 2) >= nftl->nb_blocks) { | |
177 | printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); | |
97894cda | 178 | printk(KERN_NOTICE "nb_boot_blocks (%d) + 2 > nb_blocks (%d)\n", |
1da177e4 LT |
179 | nftl->nb_boot_blocks, nftl->nb_blocks); |
180 | return -1; | |
181 | } | |
182 | ||
183 | nftl->numvunits = le32_to_cpu(mh->FormattedSize) / nftl->EraseSize; | |
184 | if (nftl->numvunits > (nftl->nb_blocks - nftl->nb_boot_blocks - 2)) { | |
185 | printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); | |
186 | printk(KERN_NOTICE "numvunits (%d) > nb_blocks (%d) - nb_boot_blocks(%d) - 2\n", | |
187 | nftl->numvunits, nftl->nb_blocks, nftl->nb_boot_blocks); | |
188 | return -1; | |
189 | } | |
97894cda | 190 | |
1da177e4 LT |
191 | nftl->mbd.size = nftl->numvunits * (nftl->EraseSize / SECTORSIZE); |
192 | ||
193 | /* If we're not using the last sectors in the device for some reason, | |
194 | reduce nb_blocks accordingly so we forget they're there */ | |
195 | nftl->nb_blocks = le16_to_cpu(mh->NumEraseUnits) + le16_to_cpu(mh->FirstPhysicalEUN); | |
196 | ||
197 | /* XXX: will be suppressed */ | |
198 | nftl->lastEUN = nftl->nb_blocks - 1; | |
199 | ||
200 | /* memory alloc */ | |
201 | nftl->EUNtable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL); | |
202 | if (!nftl->EUNtable) { | |
203 | printk(KERN_NOTICE "NFTL: allocation of EUNtable failed\n"); | |
204 | return -ENOMEM; | |
205 | } | |
206 | ||
207 | nftl->ReplUnitTable = kmalloc(nftl->nb_blocks * sizeof(u16), GFP_KERNEL); | |
208 | if (!nftl->ReplUnitTable) { | |
209 | kfree(nftl->EUNtable); | |
210 | printk(KERN_NOTICE "NFTL: allocation of ReplUnitTable failed\n"); | |
211 | return -ENOMEM; | |
212 | } | |
97894cda | 213 | |
1da177e4 LT |
214 | /* mark the bios blocks (blocks before NFTL MediaHeader) as reserved */ |
215 | for (i = 0; i < nftl->nb_boot_blocks; i++) | |
216 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; | |
217 | /* mark all remaining blocks as potentially containing data */ | |
97894cda | 218 | for (; i < nftl->nb_blocks; i++) { |
1da177e4 LT |
219 | nftl->ReplUnitTable[i] = BLOCK_NOTEXPLORED; |
220 | } | |
221 | ||
222 | /* Mark this boot record (NFTL MediaHeader) block as reserved */ | |
223 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
224 | ||
225 | /* read the Bad Erase Unit Table and modify ReplUnitTable[] accordingly */ | |
226 | for (i = 0; i < nftl->nb_blocks; i++) { | |
227 | #if 0 | |
228 | The new DiskOnChip driver already scanned the bad block table. Just query it. | |
229 | if ((i & (SECTORSIZE - 1)) == 0) { | |
230 | /* read one sector for every SECTORSIZE of blocks */ | |
f4a43cfc TG |
231 | if ((ret = mtd->read(nftl->mbd.mtd, block * nftl->EraseSize + |
232 | i + SECTORSIZE, SECTORSIZE, &retlen, | |
233 | buf)) < 0) { | |
1da177e4 LT |
234 | printk(KERN_NOTICE "Read of bad sector table failed (err %d)\n", |
235 | ret); | |
236 | kfree(nftl->ReplUnitTable); | |
237 | kfree(nftl->EUNtable); | |
238 | return -1; | |
239 | } | |
240 | } | |
241 | /* mark the Bad Erase Unit as RESERVED in ReplUnitTable */ | |
242 | if (buf[i & (SECTORSIZE - 1)] != 0xff) | |
243 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; | |
244 | #endif | |
245 | if (nftl->mbd.mtd->block_isbad(nftl->mbd.mtd, i * nftl->EraseSize)) | |
246 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; | |
247 | } | |
97894cda | 248 | |
1da177e4 LT |
249 | nftl->MediaUnit = block; |
250 | boot_record_count++; | |
97894cda | 251 | |
1da177e4 | 252 | } /* foreach (block) */ |
97894cda | 253 | |
1da177e4 LT |
254 | return boot_record_count?0:-1; |
255 | } | |
256 | ||
257 | static int memcmpb(void *a, int c, int n) | |
258 | { | |
259 | int i; | |
260 | for (i = 0; i < n; i++) { | |
261 | if (c != ((unsigned char *)a)[i]) | |
262 | return 1; | |
263 | } | |
264 | return 0; | |
265 | } | |
266 | ||
267 | /* check_free_sector: check if a free sector is actually FREE, i.e. All 0xff in data and oob area */ | |
97894cda | 268 | static int check_free_sectors(struct NFTLrecord *nftl, unsigned int address, int len, |
1da177e4 LT |
269 | int check_oob) |
270 | { | |
1da177e4 | 271 | u8 buf[SECTORSIZE + nftl->mbd.mtd->oobsize]; |
9223a456 TG |
272 | struct mtd_info *mtd = nftl->mbd.mtd; |
273 | size_t retlen; | |
274 | int i; | |
1da177e4 LT |
275 | |
276 | for (i = 0; i < len; i += SECTORSIZE) { | |
9223a456 | 277 | if (mtd->read(mtd, address, SECTORSIZE, &retlen, buf)) |
1da177e4 LT |
278 | return -1; |
279 | if (memcmpb(buf, 0xff, SECTORSIZE) != 0) | |
280 | return -1; | |
281 | ||
282 | if (check_oob) { | |
8593fbc6 | 283 | if(nftl_read_oob(mtd, address, mtd->oobsize, |
9223a456 TG |
284 | &retlen, &buf[SECTORSIZE]) < 0) |
285 | return -1; | |
286 | if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0) | |
1da177e4 LT |
287 | return -1; |
288 | } | |
289 | address += SECTORSIZE; | |
290 | } | |
291 | ||
292 | return 0; | |
293 | } | |
294 | ||
295 | /* NFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase Unit and | |
296 | * Update NFTL metadata. Each erase operation is checked with check_free_sectors | |
297 | * | |
298 | * Return: 0 when succeed, -1 on error. | |
299 | * | |
97894cda | 300 | * ToDo: 1. Is it neceressary to check_free_sector after erasing ?? |
1da177e4 LT |
301 | */ |
302 | int NFTL_formatblock(struct NFTLrecord *nftl, int block) | |
303 | { | |
304 | size_t retlen; | |
305 | unsigned int nb_erases, erase_mark; | |
306 | struct nftl_uci1 uci; | |
307 | struct erase_info *instr = &nftl->instr; | |
f4a43cfc | 308 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
309 | |
310 | /* Read the Unit Control Information #1 for Wear-Leveling */ | |
8593fbc6 | 311 | if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, |
f4a43cfc | 312 | 8, &retlen, (char *)&uci) < 0) |
1da177e4 LT |
313 | goto default_uci1; |
314 | ||
315 | erase_mark = le16_to_cpu ((uci.EraseMark | uci.EraseMark1)); | |
316 | if (erase_mark != ERASE_MARK) { | |
317 | default_uci1: | |
318 | uci.EraseMark = cpu_to_le16(ERASE_MARK); | |
319 | uci.EraseMark1 = cpu_to_le16(ERASE_MARK); | |
320 | uci.WearInfo = cpu_to_le32(0); | |
321 | } | |
322 | ||
323 | memset(instr, 0, sizeof(struct erase_info)); | |
324 | ||
325 | /* XXX: use async erase interface, XXX: test return code */ | |
326 | instr->mtd = nftl->mbd.mtd; | |
327 | instr->addr = block * nftl->EraseSize; | |
328 | instr->len = nftl->EraseSize; | |
f4a43cfc | 329 | mtd->erase(mtd, instr); |
1da177e4 LT |
330 | |
331 | if (instr->state == MTD_ERASE_FAILED) { | |
332 | printk("Error while formatting block %d\n", block); | |
333 | goto fail; | |
334 | } | |
335 | ||
336 | /* increase and write Wear-Leveling info */ | |
337 | nb_erases = le32_to_cpu(uci.WearInfo); | |
338 | nb_erases++; | |
339 | ||
340 | /* wrap (almost impossible with current flashs) or free block */ | |
341 | if (nb_erases == 0) | |
342 | nb_erases = 1; | |
343 | ||
344 | /* check the "freeness" of Erase Unit before updating metadata | |
345 | * FixMe: is this check really necessary ? since we have check the | |
346 | * return code after the erase operation. */ | |
347 | if (check_free_sectors(nftl, instr->addr, nftl->EraseSize, 1) != 0) | |
348 | goto fail; | |
349 | ||
350 | uci.WearInfo = le32_to_cpu(nb_erases); | |
8593fbc6 | 351 | if (nftl_write_oob(mtd, block * nftl->EraseSize + SECTORSIZE + |
f4a43cfc | 352 | 8, 8, &retlen, (char *)&uci) < 0) |
1da177e4 LT |
353 | goto fail; |
354 | return 0; | |
355 | fail: | |
356 | /* could not format, update the bad block table (caller is responsible | |
357 | for setting the ReplUnitTable to BLOCK_RESERVED on failure) */ | |
358 | nftl->mbd.mtd->block_markbad(nftl->mbd.mtd, instr->addr); | |
359 | return -1; | |
360 | } | |
361 | ||
362 | /* check_sectors_in_chain: Check that each sector of a Virtual Unit Chain is correct. | |
363 | * Mark as 'IGNORE' each incorrect sector. This check is only done if the chain | |
364 | * was being folded when NFTL was interrupted. | |
365 | * | |
366 | * The check_free_sectors in this function is neceressary. There is a possible | |
367 | * situation that after writing the Data area, the Block Control Information is | |
368 | * not updated according (due to power failure or something) which leaves the block | |
369 | * in an umconsistent state. So we have to check if a block is really FREE in this | |
370 | * case. */ | |
371 | static void check_sectors_in_chain(struct NFTLrecord *nftl, unsigned int first_block) | |
372 | { | |
f4a43cfc | 373 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
374 | unsigned int block, i, status; |
375 | struct nftl_bci bci; | |
376 | int sectors_per_block; | |
377 | size_t retlen; | |
378 | ||
379 | sectors_per_block = nftl->EraseSize / SECTORSIZE; | |
380 | block = first_block; | |
381 | for (;;) { | |
382 | for (i = 0; i < sectors_per_block; i++) { | |
8593fbc6 | 383 | if (nftl_read_oob(mtd, |
f4a43cfc TG |
384 | block * nftl->EraseSize + i * SECTORSIZE, |
385 | 8, &retlen, (char *)&bci) < 0) | |
1da177e4 LT |
386 | status = SECTOR_IGNORE; |
387 | else | |
388 | status = bci.Status | bci.Status1; | |
389 | ||
390 | switch(status) { | |
391 | case SECTOR_FREE: | |
392 | /* verify that the sector is really free. If not, mark | |
393 | as ignore */ | |
394 | if (memcmpb(&bci, 0xff, 8) != 0 || | |
97894cda | 395 | check_free_sectors(nftl, block * nftl->EraseSize + i * SECTORSIZE, |
1da177e4 LT |
396 | SECTORSIZE, 0) != 0) { |
397 | printk("Incorrect free sector %d in block %d: " | |
398 | "marking it as ignored\n", | |
399 | i, block); | |
400 | ||
401 | /* sector not free actually : mark it as SECTOR_IGNORE */ | |
402 | bci.Status = SECTOR_IGNORE; | |
403 | bci.Status1 = SECTOR_IGNORE; | |
8593fbc6 | 404 | nftl_write_oob(mtd, block * |
f4a43cfc TG |
405 | nftl->EraseSize + |
406 | i * SECTORSIZE, 8, | |
407 | &retlen, (char *)&bci); | |
1da177e4 LT |
408 | } |
409 | break; | |
410 | default: | |
411 | break; | |
412 | } | |
413 | } | |
414 | ||
415 | /* proceed to next Erase Unit on the chain */ | |
416 | block = nftl->ReplUnitTable[block]; | |
417 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
418 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
419 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
420 | break; | |
421 | } | |
422 | } | |
423 | ||
efad798b | 424 | /* calc_chain_length: Walk through a Virtual Unit Chain and estimate chain length */ |
1da177e4 LT |
425 | static int calc_chain_length(struct NFTLrecord *nftl, unsigned int first_block) |
426 | { | |
427 | unsigned int length = 0, block = first_block; | |
428 | ||
429 | for (;;) { | |
430 | length++; | |
431 | /* avoid infinite loops, although this is guaranted not to | |
432 | happen because of the previous checks */ | |
433 | if (length >= nftl->nb_blocks) { | |
434 | printk("nftl: length too long %d !\n", length); | |
435 | break; | |
436 | } | |
437 | ||
438 | block = nftl->ReplUnitTable[block]; | |
439 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
440 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
441 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
442 | break; | |
443 | } | |
444 | return length; | |
445 | } | |
446 | ||
447 | /* format_chain: Format an invalid Virtual Unit chain. It frees all the Erase Units in a | |
448 | * Virtual Unit Chain, i.e. all the units are disconnected. | |
449 | * | |
450 | * It is not stricly correct to begin from the first block of the chain because | |
451 | * if we stop the code, we may see again a valid chain if there was a first_block | |
452 | * flag in a block inside it. But is it really a problem ? | |
453 | * | |
454 | * FixMe: Figure out what the last statesment means. What if power failure when we are | |
455 | * in the for (;;) loop formatting blocks ?? | |
456 | */ | |
457 | static void format_chain(struct NFTLrecord *nftl, unsigned int first_block) | |
458 | { | |
459 | unsigned int block = first_block, block1; | |
460 | ||
461 | printk("Formatting chain at block %d\n", first_block); | |
462 | ||
463 | for (;;) { | |
464 | block1 = nftl->ReplUnitTable[block]; | |
465 | ||
466 | printk("Formatting block %d\n", block); | |
467 | if (NFTL_formatblock(nftl, block) < 0) { | |
468 | /* cannot format !!!! Mark it as Bad Unit */ | |
469 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
470 | } else { | |
471 | nftl->ReplUnitTable[block] = BLOCK_FREE; | |
472 | } | |
473 | ||
474 | /* goto next block on the chain */ | |
475 | block = block1; | |
476 | ||
477 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
478 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
479 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
480 | break; | |
481 | } | |
482 | } | |
483 | ||
484 | /* check_and_mark_free_block: Verify that a block is free in the NFTL sense (valid erase mark) or | |
485 | * totally free (only 0xff). | |
486 | * | |
487 | * Definition: Free Erase Unit -- A properly erased/formatted Free Erase Unit should have meet the | |
488 | * following critia: | |
489 | * 1. */ | |
490 | static int check_and_mark_free_block(struct NFTLrecord *nftl, int block) | |
491 | { | |
f4a43cfc | 492 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
493 | struct nftl_uci1 h1; |
494 | unsigned int erase_mark; | |
495 | size_t retlen; | |
496 | ||
497 | /* check erase mark. */ | |
8593fbc6 | 498 | if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8, |
f4a43cfc | 499 | &retlen, (char *)&h1) < 0) |
1da177e4 LT |
500 | return -1; |
501 | ||
502 | erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1)); | |
503 | if (erase_mark != ERASE_MARK) { | |
504 | /* if no erase mark, the block must be totally free. This is | |
505 | possible in two cases : empty filsystem or interrupted erase (very unlikely) */ | |
506 | if (check_free_sectors (nftl, block * nftl->EraseSize, nftl->EraseSize, 1) != 0) | |
507 | return -1; | |
508 | ||
509 | /* free block : write erase mark */ | |
510 | h1.EraseMark = cpu_to_le16(ERASE_MARK); | |
511 | h1.EraseMark1 = cpu_to_le16(ERASE_MARK); | |
512 | h1.WearInfo = cpu_to_le32(0); | |
8593fbc6 | 513 | if (nftl_write_oob(mtd, |
f4a43cfc TG |
514 | block * nftl->EraseSize + SECTORSIZE + 8, 8, |
515 | &retlen, (char *)&h1) < 0) | |
1da177e4 LT |
516 | return -1; |
517 | } else { | |
518 | #if 0 | |
519 | /* if erase mark present, need to skip it when doing check */ | |
520 | for (i = 0; i < nftl->EraseSize; i += SECTORSIZE) { | |
521 | /* check free sector */ | |
522 | if (check_free_sectors (nftl, block * nftl->EraseSize + i, | |
523 | SECTORSIZE, 0) != 0) | |
524 | return -1; | |
525 | ||
8593fbc6 | 526 | if (nftl_read_oob(mtd, block * nftl->EraseSize + i, |
f4a43cfc | 527 | 16, &retlen, buf) < 0) |
1da177e4 LT |
528 | return -1; |
529 | if (i == SECTORSIZE) { | |
530 | /* skip erase mark */ | |
531 | if (memcmpb(buf, 0xff, 8)) | |
532 | return -1; | |
533 | } else { | |
534 | if (memcmpb(buf, 0xff, 16)) | |
535 | return -1; | |
536 | } | |
537 | } | |
538 | #endif | |
539 | } | |
540 | ||
541 | return 0; | |
542 | } | |
543 | ||
544 | /* get_fold_mark: Read fold mark from Unit Control Information #2, we use FOLD_MARK_IN_PROGRESS | |
545 | * to indicate that we are in the progression of a Virtual Unit Chain folding. If the UCI #2 | |
546 | * is FOLD_MARK_IN_PROGRESS when mounting the NFTL, the (previous) folding process is interrupted | |
547 | * for some reason. A clean up/check of the VUC is neceressary in this case. | |
548 | * | |
549 | * WARNING: return 0 if read error | |
550 | */ | |
551 | static int get_fold_mark(struct NFTLrecord *nftl, unsigned int block) | |
552 | { | |
f4a43cfc | 553 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
554 | struct nftl_uci2 uci; |
555 | size_t retlen; | |
556 | ||
8593fbc6 | 557 | if (nftl_read_oob(mtd, block * nftl->EraseSize + 2 * SECTORSIZE + 8, |
f4a43cfc | 558 | 8, &retlen, (char *)&uci) < 0) |
1da177e4 LT |
559 | return 0; |
560 | ||
561 | return le16_to_cpu((uci.FoldMark | uci.FoldMark1)); | |
562 | } | |
563 | ||
564 | int NFTL_mount(struct NFTLrecord *s) | |
565 | { | |
566 | int i; | |
567 | unsigned int first_logical_block, logical_block, rep_block, nb_erases, erase_mark; | |
568 | unsigned int block, first_block, is_first_block; | |
569 | int chain_length, do_format_chain; | |
570 | struct nftl_uci0 h0; | |
571 | struct nftl_uci1 h1; | |
f4a43cfc | 572 | struct mtd_info *mtd = s->mbd.mtd; |
1da177e4 LT |
573 | size_t retlen; |
574 | ||
575 | /* search for NFTL MediaHeader and Spare NFTL Media Header */ | |
576 | if (find_boot_record(s) < 0) { | |
577 | printk("Could not find valid boot record\n"); | |
578 | return -1; | |
579 | } | |
580 | ||
581 | /* init the logical to physical table */ | |
582 | for (i = 0; i < s->nb_blocks; i++) { | |
583 | s->EUNtable[i] = BLOCK_NIL; | |
584 | } | |
585 | ||
586 | /* first pass : explore each block chain */ | |
587 | first_logical_block = 0; | |
588 | for (first_block = 0; first_block < s->nb_blocks; first_block++) { | |
589 | /* if the block was not already explored, we can look at it */ | |
590 | if (s->ReplUnitTable[first_block] == BLOCK_NOTEXPLORED) { | |
591 | block = first_block; | |
592 | chain_length = 0; | |
593 | do_format_chain = 0; | |
594 | ||
595 | for (;;) { | |
596 | /* read the block header. If error, we format the chain */ | |
8593fbc6 | 597 | if (nftl_read_oob(mtd, |
f4a43cfc TG |
598 | block * s->EraseSize + 8, 8, |
599 | &retlen, (char *)&h0) < 0 || | |
8593fbc6 | 600 | nftl_read_oob(mtd, |
f4a43cfc TG |
601 | block * s->EraseSize + |
602 | SECTORSIZE + 8, 8, | |
603 | &retlen, (char *)&h1) < 0) { | |
1da177e4 LT |
604 | s->ReplUnitTable[block] = BLOCK_NIL; |
605 | do_format_chain = 1; | |
606 | break; | |
607 | } | |
608 | ||
609 | logical_block = le16_to_cpu ((h0.VirtUnitNum | h0.SpareVirtUnitNum)); | |
610 | rep_block = le16_to_cpu ((h0.ReplUnitNum | h0.SpareReplUnitNum)); | |
611 | nb_erases = le32_to_cpu (h1.WearInfo); | |
612 | erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1)); | |
613 | ||
614 | is_first_block = !(logical_block >> 15); | |
615 | logical_block = logical_block & 0x7fff; | |
616 | ||
617 | /* invalid/free block test */ | |
618 | if (erase_mark != ERASE_MARK || logical_block >= s->nb_blocks) { | |
619 | if (chain_length == 0) { | |
620 | /* if not currently in a chain, we can handle it safely */ | |
621 | if (check_and_mark_free_block(s, block) < 0) { | |
622 | /* not really free: format it */ | |
623 | printk("Formatting block %d\n", block); | |
624 | if (NFTL_formatblock(s, block) < 0) { | |
625 | /* could not format: reserve the block */ | |
626 | s->ReplUnitTable[block] = BLOCK_RESERVED; | |
627 | } else { | |
628 | s->ReplUnitTable[block] = BLOCK_FREE; | |
629 | } | |
630 | } else { | |
631 | /* free block: mark it */ | |
632 | s->ReplUnitTable[block] = BLOCK_FREE; | |
633 | } | |
634 | /* directly examine the next block. */ | |
635 | goto examine_ReplUnitTable; | |
636 | } else { | |
637 | /* the block was in a chain : this is bad. We | |
638 | must format all the chain */ | |
639 | printk("Block %d: free but referenced in chain %d\n", | |
640 | block, first_block); | |
641 | s->ReplUnitTable[block] = BLOCK_NIL; | |
642 | do_format_chain = 1; | |
643 | break; | |
644 | } | |
645 | } | |
646 | ||
647 | /* we accept only first blocks here */ | |
648 | if (chain_length == 0) { | |
649 | /* this block is not the first block in chain : | |
650 | ignore it, it will be included in a chain | |
651 | later, or marked as not explored */ | |
652 | if (!is_first_block) | |
653 | goto examine_ReplUnitTable; | |
654 | first_logical_block = logical_block; | |
655 | } else { | |
656 | if (logical_block != first_logical_block) { | |
97894cda | 657 | printk("Block %d: incorrect logical block: %d expected: %d\n", |
1da177e4 LT |
658 | block, logical_block, first_logical_block); |
659 | /* the chain is incorrect : we must format it, | |
660 | but we need to read it completly */ | |
661 | do_format_chain = 1; | |
662 | } | |
663 | if (is_first_block) { | |
664 | /* we accept that a block is marked as first | |
665 | block while being last block in a chain | |
666 | only if the chain is being folded */ | |
667 | if (get_fold_mark(s, block) != FOLD_MARK_IN_PROGRESS || | |
668 | rep_block != 0xffff) { | |
669 | printk("Block %d: incorrectly marked as first block in chain\n", | |
670 | block); | |
671 | /* the chain is incorrect : we must format it, | |
672 | but we need to read it completly */ | |
673 | do_format_chain = 1; | |
674 | } else { | |
675 | printk("Block %d: folding in progress - ignoring first block flag\n", | |
676 | block); | |
677 | } | |
678 | } | |
679 | } | |
680 | chain_length++; | |
681 | if (rep_block == 0xffff) { | |
682 | /* no more blocks after */ | |
683 | s->ReplUnitTable[block] = BLOCK_NIL; | |
684 | break; | |
685 | } else if (rep_block >= s->nb_blocks) { | |
97894cda | 686 | printk("Block %d: referencing invalid block %d\n", |
1da177e4 LT |
687 | block, rep_block); |
688 | do_format_chain = 1; | |
689 | s->ReplUnitTable[block] = BLOCK_NIL; | |
690 | break; | |
691 | } else if (s->ReplUnitTable[rep_block] != BLOCK_NOTEXPLORED) { | |
692 | /* same problem as previous 'is_first_block' test: | |
693 | we accept that the last block of a chain has | |
694 | the first_block flag set if folding is in | |
695 | progress. We handle here the case where the | |
696 | last block appeared first */ | |
697 | if (s->ReplUnitTable[rep_block] == BLOCK_NIL && | |
698 | s->EUNtable[first_logical_block] == rep_block && | |
699 | get_fold_mark(s, first_block) == FOLD_MARK_IN_PROGRESS) { | |
700 | /* EUNtable[] will be set after */ | |
701 | printk("Block %d: folding in progress - ignoring first block flag\n", | |
702 | rep_block); | |
703 | s->ReplUnitTable[block] = rep_block; | |
704 | s->EUNtable[first_logical_block] = BLOCK_NIL; | |
705 | } else { | |
97894cda | 706 | printk("Block %d: referencing block %d already in another chain\n", |
1da177e4 LT |
707 | block, rep_block); |
708 | /* XXX: should handle correctly fold in progress chains */ | |
709 | do_format_chain = 1; | |
710 | s->ReplUnitTable[block] = BLOCK_NIL; | |
711 | } | |
712 | break; | |
713 | } else { | |
714 | /* this is OK */ | |
715 | s->ReplUnitTable[block] = rep_block; | |
716 | block = rep_block; | |
717 | } | |
718 | } | |
719 | ||
720 | /* the chain was completely explored. Now we can decide | |
721 | what to do with it */ | |
722 | if (do_format_chain) { | |
723 | /* invalid chain : format it */ | |
724 | format_chain(s, first_block); | |
725 | } else { | |
726 | unsigned int first_block1, chain_to_format, chain_length1; | |
727 | int fold_mark; | |
97894cda | 728 | |
1da177e4 LT |
729 | /* valid chain : get foldmark */ |
730 | fold_mark = get_fold_mark(s, first_block); | |
731 | if (fold_mark == 0) { | |
732 | /* cannot get foldmark : format the chain */ | |
733 | printk("Could read foldmark at block %d\n", first_block); | |
734 | format_chain(s, first_block); | |
735 | } else { | |
736 | if (fold_mark == FOLD_MARK_IN_PROGRESS) | |
737 | check_sectors_in_chain(s, first_block); | |
738 | ||
739 | /* now handle the case where we find two chains at the | |
740 | same virtual address : we select the longer one, | |
741 | because the shorter one is the one which was being | |
742 | folded if the folding was not done in place */ | |
743 | first_block1 = s->EUNtable[first_logical_block]; | |
744 | if (first_block1 != BLOCK_NIL) { | |
745 | /* XXX: what to do if same length ? */ | |
746 | chain_length1 = calc_chain_length(s, first_block1); | |
97894cda | 747 | printk("Two chains at blocks %d (len=%d) and %d (len=%d)\n", |
1da177e4 | 748 | first_block1, chain_length1, first_block, chain_length); |
97894cda | 749 | |
1da177e4 LT |
750 | if (chain_length >= chain_length1) { |
751 | chain_to_format = first_block1; | |
752 | s->EUNtable[first_logical_block] = first_block; | |
753 | } else { | |
754 | chain_to_format = first_block; | |
755 | } | |
756 | format_chain(s, chain_to_format); | |
757 | } else { | |
758 | s->EUNtable[first_logical_block] = first_block; | |
759 | } | |
760 | } | |
761 | } | |
762 | } | |
763 | examine_ReplUnitTable:; | |
764 | } | |
765 | ||
766 | /* second pass to format unreferenced blocks and init free block count */ | |
767 | s->numfreeEUNs = 0; | |
768 | s->LastFreeEUN = le16_to_cpu(s->MediaHdr.FirstPhysicalEUN); | |
769 | ||
770 | for (block = 0; block < s->nb_blocks; block++) { | |
771 | if (s->ReplUnitTable[block] == BLOCK_NOTEXPLORED) { | |
772 | printk("Unreferenced block %d, formatting it\n", block); | |
773 | if (NFTL_formatblock(s, block) < 0) | |
774 | s->ReplUnitTable[block] = BLOCK_RESERVED; | |
775 | else | |
776 | s->ReplUnitTable[block] = BLOCK_FREE; | |
777 | } | |
778 | if (s->ReplUnitTable[block] == BLOCK_FREE) { | |
779 | s->numfreeEUNs++; | |
780 | s->LastFreeEUN = block; | |
781 | } | |
782 | } | |
783 | ||
784 | return 0; | |
785 | } |