Commit | Line | Data |
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1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
97894cda | 2 | /* |
1da177e4 LT |
3 | * NFTL mount code with extensive checks |
4 | * | |
97894cda | 5 | * Author: Fabrice Bellard (fabrice.bellard@netgem.com) |
a1452a37 DW |
6 | * Copyright © 2000 Netgem S.A. |
7 | * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> | |
1da177e4 LT |
8 | */ |
9 | ||
10 | #include <linux/kernel.h> | |
11 | #include <asm/errno.h> | |
12 | #include <linux/delay.h> | |
13 | #include <linux/slab.h> | |
14 | #include <linux/mtd/mtd.h> | |
d4092d76 | 15 | #include <linux/mtd/rawnand.h> |
1da177e4 LT |
16 | #include <linux/mtd/nftl.h> |
17 | ||
18 | #define SECTORSIZE 512 | |
19 | ||
1da177e4 LT |
20 | /* find_boot_record: Find the NFTL Media Header and its Spare copy which contains the |
21 | * various device information of the NFTL partition and Bad Unit Table. Update | |
92394b5c | 22 | * the ReplUnitTable[] table according to the Bad Unit Table. ReplUnitTable[] |
1da177e4 LT |
23 | * is used for management of Erase Unit in other routines in nftl.c and nftlmount.c |
24 | */ | |
25 | static int find_boot_record(struct NFTLrecord *nftl) | |
26 | { | |
27 | struct nftl_uci1 h1; | |
28 | unsigned int block, boot_record_count = 0; | |
29 | size_t retlen; | |
30 | u8 buf[SECTORSIZE]; | |
31 | struct NFTLMediaHeader *mh = &nftl->MediaHdr; | |
f4a43cfc | 32 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
33 | unsigned int i; |
34 | ||
97894cda | 35 | /* Assume logical EraseSize == physical erasesize for starting the scan. |
1da177e4 LT |
36 | We'll sort it out later if we find a MediaHeader which says otherwise */ |
37 | /* Actually, we won't. The new DiskOnChip driver has already scanned | |
38 | the MediaHeader and adjusted the virtual erasesize it presents in | |
39 | the mtd device accordingly. We could even get rid of | |
40 | nftl->EraseSize if there were any point in doing so. */ | |
41 | nftl->EraseSize = nftl->mbd.mtd->erasesize; | |
69423d99 | 42 | nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize; |
1da177e4 LT |
43 | |
44 | nftl->MediaUnit = BLOCK_NIL; | |
45 | nftl->SpareMediaUnit = BLOCK_NIL; | |
46 | ||
47 | /* search for a valid boot record */ | |
48 | for (block = 0; block < nftl->nb_blocks; block++) { | |
49 | int ret; | |
50 | ||
51 | /* Check for ANAND header first. Then can whinge if it's found but later | |
52 | checks fail */ | |
329ad399 AB |
53 | ret = mtd_read(mtd, block * nftl->EraseSize, SECTORSIZE, |
54 | &retlen, buf); | |
1da177e4 LT |
55 | /* We ignore ret in case the ECC of the MediaHeader is invalid |
56 | (which is apparently acceptable) */ | |
57 | if (retlen != SECTORSIZE) { | |
58 | static int warncount = 5; | |
59 | ||
60 | if (warncount) { | |
61 | printk(KERN_WARNING "Block read at 0x%x of mtd%d failed: %d\n", | |
62 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
63 | if (!--warncount) | |
64 | printk(KERN_WARNING "Further failures for this block will not be printed\n"); | |
65 | } | |
66 | continue; | |
67 | } | |
68 | ||
69 | if (retlen < 6 || memcmp(buf, "ANAND", 6)) { | |
70 | /* ANAND\0 not found. Continue */ | |
71 | #if 0 | |
97894cda | 72 | printk(KERN_DEBUG "ANAND header not found at 0x%x in mtd%d\n", |
1da177e4 | 73 | block * nftl->EraseSize, nftl->mbd.mtd->index); |
97894cda | 74 | #endif |
1da177e4 LT |
75 | continue; |
76 | } | |
77 | ||
78 | /* To be safer with BIOS, also use erase mark as discriminant */ | |
768c57c8 | 79 | ret = nftl_read_oob(mtd, block * nftl->EraseSize + |
f4a43cfc | 80 | SECTORSIZE + 8, 8, &retlen, |
768c57c8 AS |
81 | (char *)&h1); |
82 | if (ret < 0) { | |
1da177e4 LT |
83 | printk(KERN_WARNING "ANAND header found at 0x%x in mtd%d, but OOB data read failed (err %d)\n", |
84 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
85 | continue; | |
86 | } | |
87 | ||
88 | #if 0 /* Some people seem to have devices without ECC or erase marks | |
89 | on the Media Header blocks. There are enough other sanity | |
90 | checks in here that we can probably do without it. | |
91 | */ | |
92 | if (le16_to_cpu(h1.EraseMark | h1.EraseMark1) != ERASE_MARK) { | |
93 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but erase mark not present (0x%04x,0x%04x instead)\n", | |
97894cda | 94 | block * nftl->EraseSize, nftl->mbd.mtd->index, |
1da177e4 LT |
95 | le16_to_cpu(h1.EraseMark), le16_to_cpu(h1.EraseMark1)); |
96 | continue; | |
97 | } | |
98 | ||
99 | /* Finally reread to check ECC */ | |
768c57c8 AS |
100 | ret = mtd->read(mtd, block * nftl->EraseSize, SECTORSIZE, |
101 | &retlen, buf); | |
102 | if (ret < 0) { | |
1da177e4 LT |
103 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but ECC read failed (err %d)\n", |
104 | block * nftl->EraseSize, nftl->mbd.mtd->index, ret); | |
105 | continue; | |
106 | } | |
107 | ||
108 | /* Paranoia. Check the ANAND header is still there after the ECC read */ | |
109 | if (memcmp(buf, "ANAND", 6)) { | |
110 | printk(KERN_NOTICE "ANAND header found at 0x%x in mtd%d, but went away on reread!\n", | |
111 | block * nftl->EraseSize, nftl->mbd.mtd->index); | |
ac9cd36c | 112 | printk(KERN_NOTICE "New data are: %6ph\n", buf); |
1da177e4 LT |
113 | continue; |
114 | } | |
115 | #endif | |
116 | /* OK, we like it. */ | |
117 | ||
118 | if (boot_record_count) { | |
119 | /* We've already processed one. So we just check if | |
120 | this one is the same as the first one we found */ | |
121 | if (memcmp(mh, buf, sizeof(struct NFTLMediaHeader))) { | |
122 | printk(KERN_NOTICE "NFTL Media Headers at 0x%x and 0x%x disagree.\n", | |
123 | nftl->MediaUnit * nftl->EraseSize, block * nftl->EraseSize); | |
124 | /* if (debug) Print both side by side */ | |
125 | if (boot_record_count < 2) { | |
126 | /* We haven't yet seen two real ones */ | |
127 | return -1; | |
128 | } | |
129 | continue; | |
130 | } | |
131 | if (boot_record_count == 1) | |
132 | nftl->SpareMediaUnit = block; | |
133 | ||
134 | /* Mark this boot record (NFTL MediaHeader) block as reserved */ | |
135 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
136 | ||
137 | ||
138 | boot_record_count++; | |
139 | continue; | |
140 | } | |
141 | ||
142 | /* This is the first we've seen. Copy the media header structure into place */ | |
143 | memcpy(mh, buf, sizeof(struct NFTLMediaHeader)); | |
144 | ||
145 | /* Do some sanity checks on it */ | |
146 | #if 0 | |
147 | The new DiskOnChip driver scans the MediaHeader itself, and presents a virtual | |
148 | erasesize based on UnitSizeFactor. So the erasesize we read from the mtd | |
149 | device is already correct. | |
150 | if (mh->UnitSizeFactor == 0) { | |
151 | printk(KERN_NOTICE "NFTL: UnitSizeFactor 0x00 detected. This violates the spec but we think we know what it means...\n"); | |
152 | } else if (mh->UnitSizeFactor < 0xfc) { | |
153 | printk(KERN_NOTICE "Sorry, we don't support UnitSizeFactor 0x%02x\n", | |
154 | mh->UnitSizeFactor); | |
155 | return -1; | |
156 | } else if (mh->UnitSizeFactor != 0xff) { | |
157 | printk(KERN_NOTICE "WARNING: Support for NFTL with UnitSizeFactor 0x%02x is experimental\n", | |
158 | mh->UnitSizeFactor); | |
159 | nftl->EraseSize = nftl->mbd.mtd->erasesize << (0xff - mh->UnitSizeFactor); | |
69423d99 | 160 | nftl->nb_blocks = (u32)nftl->mbd.mtd->size / nftl->EraseSize; |
1da177e4 LT |
161 | } |
162 | #endif | |
163 | nftl->nb_boot_blocks = le16_to_cpu(mh->FirstPhysicalEUN); | |
164 | if ((nftl->nb_boot_blocks + 2) >= nftl->nb_blocks) { | |
165 | printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); | |
97894cda | 166 | printk(KERN_NOTICE "nb_boot_blocks (%d) + 2 > nb_blocks (%d)\n", |
1da177e4 LT |
167 | nftl->nb_boot_blocks, nftl->nb_blocks); |
168 | return -1; | |
169 | } | |
170 | ||
171 | nftl->numvunits = le32_to_cpu(mh->FormattedSize) / nftl->EraseSize; | |
172 | if (nftl->numvunits > (nftl->nb_blocks - nftl->nb_boot_blocks - 2)) { | |
173 | printk(KERN_NOTICE "NFTL Media Header sanity check failed:\n"); | |
174 | printk(KERN_NOTICE "numvunits (%d) > nb_blocks (%d) - nb_boot_blocks(%d) - 2\n", | |
175 | nftl->numvunits, nftl->nb_blocks, nftl->nb_boot_blocks); | |
176 | return -1; | |
177 | } | |
97894cda | 178 | |
1da177e4 LT |
179 | nftl->mbd.size = nftl->numvunits * (nftl->EraseSize / SECTORSIZE); |
180 | ||
181 | /* If we're not using the last sectors in the device for some reason, | |
182 | reduce nb_blocks accordingly so we forget they're there */ | |
183 | nftl->nb_blocks = le16_to_cpu(mh->NumEraseUnits) + le16_to_cpu(mh->FirstPhysicalEUN); | |
184 | ||
185 | /* XXX: will be suppressed */ | |
186 | nftl->lastEUN = nftl->nb_blocks - 1; | |
187 | ||
188 | /* memory alloc */ | |
6da2ec56 KC |
189 | nftl->EUNtable = kmalloc_array(nftl->nb_blocks, sizeof(u16), |
190 | GFP_KERNEL); | |
1da177e4 LT |
191 | if (!nftl->EUNtable) { |
192 | printk(KERN_NOTICE "NFTL: allocation of EUNtable failed\n"); | |
193 | return -ENOMEM; | |
194 | } | |
195 | ||
6da2ec56 KC |
196 | nftl->ReplUnitTable = kmalloc_array(nftl->nb_blocks, |
197 | sizeof(u16), | |
198 | GFP_KERNEL); | |
1da177e4 LT |
199 | if (!nftl->ReplUnitTable) { |
200 | kfree(nftl->EUNtable); | |
201 | printk(KERN_NOTICE "NFTL: allocation of ReplUnitTable failed\n"); | |
202 | return -ENOMEM; | |
203 | } | |
97894cda | 204 | |
1da177e4 LT |
205 | /* mark the bios blocks (blocks before NFTL MediaHeader) as reserved */ |
206 | for (i = 0; i < nftl->nb_boot_blocks; i++) | |
207 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; | |
208 | /* mark all remaining blocks as potentially containing data */ | |
97894cda | 209 | for (; i < nftl->nb_blocks; i++) { |
1da177e4 LT |
210 | nftl->ReplUnitTable[i] = BLOCK_NOTEXPLORED; |
211 | } | |
212 | ||
213 | /* Mark this boot record (NFTL MediaHeader) block as reserved */ | |
214 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
215 | ||
216 | /* read the Bad Erase Unit Table and modify ReplUnitTable[] accordingly */ | |
217 | for (i = 0; i < nftl->nb_blocks; i++) { | |
218 | #if 0 | |
219 | The new DiskOnChip driver already scanned the bad block table. Just query it. | |
220 | if ((i & (SECTORSIZE - 1)) == 0) { | |
221 | /* read one sector for every SECTORSIZE of blocks */ | |
768c57c8 AS |
222 | ret = mtd->read(nftl->mbd.mtd, |
223 | block * nftl->EraseSize + i + | |
224 | SECTORSIZE, SECTORSIZE, | |
225 | &retlen, buf); | |
226 | if (ret < 0) { | |
1da177e4 LT |
227 | printk(KERN_NOTICE "Read of bad sector table failed (err %d)\n", |
228 | ret); | |
229 | kfree(nftl->ReplUnitTable); | |
230 | kfree(nftl->EUNtable); | |
231 | return -1; | |
232 | } | |
233 | } | |
234 | /* mark the Bad Erase Unit as RESERVED in ReplUnitTable */ | |
235 | if (buf[i & (SECTORSIZE - 1)] != 0xff) | |
236 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; | |
237 | #endif | |
7086c19d AB |
238 | if (mtd_block_isbad(nftl->mbd.mtd, |
239 | i * nftl->EraseSize)) | |
1da177e4 LT |
240 | nftl->ReplUnitTable[i] = BLOCK_RESERVED; |
241 | } | |
97894cda | 242 | |
1da177e4 LT |
243 | nftl->MediaUnit = block; |
244 | boot_record_count++; | |
97894cda | 245 | |
1da177e4 | 246 | } /* foreach (block) */ |
97894cda | 247 | |
1da177e4 LT |
248 | return boot_record_count?0:-1; |
249 | } | |
250 | ||
251 | static int memcmpb(void *a, int c, int n) | |
252 | { | |
253 | int i; | |
254 | for (i = 0; i < n; i++) { | |
255 | if (c != ((unsigned char *)a)[i]) | |
256 | return 1; | |
257 | } | |
258 | return 0; | |
259 | } | |
260 | ||
261 | /* check_free_sector: check if a free sector is actually FREE, i.e. All 0xff in data and oob area */ | |
97894cda | 262 | static int check_free_sectors(struct NFTLrecord *nftl, unsigned int address, int len, |
1da177e4 LT |
263 | int check_oob) |
264 | { | |
9223a456 TG |
265 | struct mtd_info *mtd = nftl->mbd.mtd; |
266 | size_t retlen; | |
27ab41e2 KC |
267 | int i, ret; |
268 | u8 *buf; | |
269 | ||
270 | buf = kmalloc(SECTORSIZE + mtd->oobsize, GFP_KERNEL); | |
271 | if (!buf) | |
272 | return -1; | |
1da177e4 | 273 | |
27ab41e2 | 274 | ret = -1; |
1da177e4 | 275 | for (i = 0; i < len; i += SECTORSIZE) { |
329ad399 | 276 | if (mtd_read(mtd, address, SECTORSIZE, &retlen, buf)) |
27ab41e2 | 277 | goto out; |
1da177e4 | 278 | if (memcmpb(buf, 0xff, SECTORSIZE) != 0) |
27ab41e2 | 279 | goto out; |
1da177e4 LT |
280 | |
281 | if (check_oob) { | |
8593fbc6 | 282 | if(nftl_read_oob(mtd, address, mtd->oobsize, |
9223a456 | 283 | &retlen, &buf[SECTORSIZE]) < 0) |
27ab41e2 | 284 | goto out; |
9223a456 | 285 | if (memcmpb(buf + SECTORSIZE, 0xff, mtd->oobsize) != 0) |
27ab41e2 | 286 | goto out; |
1da177e4 LT |
287 | } |
288 | address += SECTORSIZE; | |
289 | } | |
290 | ||
27ab41e2 KC |
291 | ret = 0; |
292 | ||
293 | out: | |
294 | kfree(buf); | |
295 | return ret; | |
1da177e4 LT |
296 | } |
297 | ||
298 | /* NFTL_format: format a Erase Unit by erasing ALL Erase Zones in the Erase Unit and | |
299 | * Update NFTL metadata. Each erase operation is checked with check_free_sectors | |
300 | * | |
301 | * Return: 0 when succeed, -1 on error. | |
302 | * | |
92394b5c | 303 | * ToDo: 1. Is it necessary to check_free_sector after erasing ?? |
1da177e4 LT |
304 | */ |
305 | int NFTL_formatblock(struct NFTLrecord *nftl, int block) | |
306 | { | |
307 | size_t retlen; | |
308 | unsigned int nb_erases, erase_mark; | |
309 | struct nftl_uci1 uci; | |
310 | struct erase_info *instr = &nftl->instr; | |
f4a43cfc | 311 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
312 | |
313 | /* Read the Unit Control Information #1 for Wear-Leveling */ | |
8593fbc6 | 314 | if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, |
f4a43cfc | 315 | 8, &retlen, (char *)&uci) < 0) |
1da177e4 LT |
316 | goto default_uci1; |
317 | ||
318 | erase_mark = le16_to_cpu ((uci.EraseMark | uci.EraseMark1)); | |
319 | if (erase_mark != ERASE_MARK) { | |
320 | default_uci1: | |
321 | uci.EraseMark = cpu_to_le16(ERASE_MARK); | |
322 | uci.EraseMark1 = cpu_to_le16(ERASE_MARK); | |
323 | uci.WearInfo = cpu_to_le32(0); | |
324 | } | |
325 | ||
326 | memset(instr, 0, sizeof(struct erase_info)); | |
327 | ||
328 | /* XXX: use async erase interface, XXX: test return code */ | |
1da177e4 LT |
329 | instr->addr = block * nftl->EraseSize; |
330 | instr->len = nftl->EraseSize; | |
884cfd90 | 331 | if (mtd_erase(mtd, instr)) { |
1da177e4 LT |
332 | printk("Error while formatting block %d\n", block); |
333 | goto fail; | |
334 | } | |
335 | ||
4845a077 CIK |
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 flash) 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 | */ | |
348 | if (check_free_sectors(nftl, instr->addr, nftl->EraseSize, 1) != 0) | |
349 | goto fail; | |
350 | ||
351 | uci.WearInfo = le32_to_cpu(nb_erases); | |
352 | if (nftl_write_oob(mtd, block * nftl->EraseSize + SECTORSIZE + | |
353 | 8, 8, &retlen, (char *)&uci) < 0) | |
354 | goto fail; | |
355 | return 0; | |
1da177e4 LT |
356 | fail: |
357 | /* could not format, update the bad block table (caller is responsible | |
358 | for setting the ReplUnitTable to BLOCK_RESERVED on failure) */ | |
5942ddbc | 359 | mtd_block_markbad(nftl->mbd.mtd, instr->addr); |
1da177e4 LT |
360 | return -1; |
361 | } | |
362 | ||
363 | /* check_sectors_in_chain: Check that each sector of a Virtual Unit Chain is correct. | |
364 | * Mark as 'IGNORE' each incorrect sector. This check is only done if the chain | |
365 | * was being folded when NFTL was interrupted. | |
366 | * | |
92394b5c | 367 | * The check_free_sectors in this function is necessary. There is a possible |
1da177e4 LT |
368 | * situation that after writing the Data area, the Block Control Information is |
369 | * not updated according (due to power failure or something) which leaves the block | |
92394b5c | 370 | * in an inconsistent state. So we have to check if a block is really FREE in this |
1da177e4 LT |
371 | * case. */ |
372 | static void check_sectors_in_chain(struct NFTLrecord *nftl, unsigned int first_block) | |
373 | { | |
f4a43cfc | 374 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
375 | unsigned int block, i, status; |
376 | struct nftl_bci bci; | |
377 | int sectors_per_block; | |
378 | size_t retlen; | |
379 | ||
380 | sectors_per_block = nftl->EraseSize / SECTORSIZE; | |
381 | block = first_block; | |
382 | for (;;) { | |
383 | for (i = 0; i < sectors_per_block; i++) { | |
8593fbc6 | 384 | if (nftl_read_oob(mtd, |
f4a43cfc TG |
385 | block * nftl->EraseSize + i * SECTORSIZE, |
386 | 8, &retlen, (char *)&bci) < 0) | |
1da177e4 LT |
387 | status = SECTOR_IGNORE; |
388 | else | |
389 | status = bci.Status | bci.Status1; | |
390 | ||
391 | switch(status) { | |
392 | case SECTOR_FREE: | |
393 | /* verify that the sector is really free. If not, mark | |
394 | as ignore */ | |
395 | if (memcmpb(&bci, 0xff, 8) != 0 || | |
97894cda | 396 | check_free_sectors(nftl, block * nftl->EraseSize + i * SECTORSIZE, |
1da177e4 LT |
397 | SECTORSIZE, 0) != 0) { |
398 | printk("Incorrect free sector %d in block %d: " | |
399 | "marking it as ignored\n", | |
400 | i, block); | |
401 | ||
402 | /* sector not free actually : mark it as SECTOR_IGNORE */ | |
403 | bci.Status = SECTOR_IGNORE; | |
404 | bci.Status1 = SECTOR_IGNORE; | |
8593fbc6 | 405 | nftl_write_oob(mtd, block * |
f4a43cfc TG |
406 | nftl->EraseSize + |
407 | i * SECTORSIZE, 8, | |
408 | &retlen, (char *)&bci); | |
1da177e4 LT |
409 | } |
410 | break; | |
411 | default: | |
412 | break; | |
413 | } | |
414 | } | |
415 | ||
416 | /* proceed to next Erase Unit on the chain */ | |
417 | block = nftl->ReplUnitTable[block]; | |
418 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
419 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
420 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
421 | break; | |
422 | } | |
423 | } | |
424 | ||
efad798b | 425 | /* calc_chain_length: Walk through a Virtual Unit Chain and estimate chain length */ |
1da177e4 LT |
426 | static int calc_chain_length(struct NFTLrecord *nftl, unsigned int first_block) |
427 | { | |
428 | unsigned int length = 0, block = first_block; | |
429 | ||
430 | for (;;) { | |
431 | length++; | |
92394b5c | 432 | /* avoid infinite loops, although this is guaranteed not to |
1da177e4 LT |
433 | happen because of the previous checks */ |
434 | if (length >= nftl->nb_blocks) { | |
435 | printk("nftl: length too long %d !\n", length); | |
436 | break; | |
437 | } | |
438 | ||
439 | block = nftl->ReplUnitTable[block]; | |
440 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
441 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
442 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
443 | break; | |
444 | } | |
445 | return length; | |
446 | } | |
447 | ||
448 | /* format_chain: Format an invalid Virtual Unit chain. It frees all the Erase Units in a | |
449 | * Virtual Unit Chain, i.e. all the units are disconnected. | |
450 | * | |
92394b5c | 451 | * It is not strictly correct to begin from the first block of the chain because |
1da177e4 LT |
452 | * if we stop the code, we may see again a valid chain if there was a first_block |
453 | * flag in a block inside it. But is it really a problem ? | |
454 | * | |
92394b5c | 455 | * FixMe: Figure out what the last statement means. What if power failure when we are |
1da177e4 LT |
456 | * in the for (;;) loop formatting blocks ?? |
457 | */ | |
458 | static void format_chain(struct NFTLrecord *nftl, unsigned int first_block) | |
459 | { | |
460 | unsigned int block = first_block, block1; | |
461 | ||
462 | printk("Formatting chain at block %d\n", first_block); | |
463 | ||
464 | for (;;) { | |
465 | block1 = nftl->ReplUnitTable[block]; | |
466 | ||
467 | printk("Formatting block %d\n", block); | |
468 | if (NFTL_formatblock(nftl, block) < 0) { | |
469 | /* cannot format !!!! Mark it as Bad Unit */ | |
470 | nftl->ReplUnitTable[block] = BLOCK_RESERVED; | |
471 | } else { | |
472 | nftl->ReplUnitTable[block] = BLOCK_FREE; | |
473 | } | |
474 | ||
475 | /* goto next block on the chain */ | |
476 | block = block1; | |
477 | ||
478 | if (!(block == BLOCK_NIL || block < nftl->nb_blocks)) | |
479 | printk("incorrect ReplUnitTable[] : %d\n", block); | |
480 | if (block == BLOCK_NIL || block >= nftl->nb_blocks) | |
481 | break; | |
482 | } | |
483 | } | |
484 | ||
485 | /* check_and_mark_free_block: Verify that a block is free in the NFTL sense (valid erase mark) or | |
486 | * totally free (only 0xff). | |
487 | * | |
488 | * Definition: Free Erase Unit -- A properly erased/formatted Free Erase Unit should have meet the | |
92394b5c | 489 | * following criteria: |
1da177e4 LT |
490 | * 1. */ |
491 | static int check_and_mark_free_block(struct NFTLrecord *nftl, int block) | |
492 | { | |
f4a43cfc | 493 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
494 | struct nftl_uci1 h1; |
495 | unsigned int erase_mark; | |
496 | size_t retlen; | |
497 | ||
498 | /* check erase mark. */ | |
8593fbc6 | 499 | if (nftl_read_oob(mtd, block * nftl->EraseSize + SECTORSIZE + 8, 8, |
f4a43cfc | 500 | &retlen, (char *)&h1) < 0) |
1da177e4 LT |
501 | return -1; |
502 | ||
503 | erase_mark = le16_to_cpu ((h1.EraseMark | h1.EraseMark1)); | |
504 | if (erase_mark != ERASE_MARK) { | |
505 | /* if no erase mark, the block must be totally free. This is | |
92394b5c | 506 | possible in two cases : empty filesystem or interrupted erase (very unlikely) */ |
1da177e4 LT |
507 | if (check_free_sectors (nftl, block * nftl->EraseSize, nftl->EraseSize, 1) != 0) |
508 | return -1; | |
509 | ||
510 | /* free block : write erase mark */ | |
511 | h1.EraseMark = cpu_to_le16(ERASE_MARK); | |
512 | h1.EraseMark1 = cpu_to_le16(ERASE_MARK); | |
513 | h1.WearInfo = cpu_to_le32(0); | |
8593fbc6 | 514 | if (nftl_write_oob(mtd, |
f4a43cfc TG |
515 | block * nftl->EraseSize + SECTORSIZE + 8, 8, |
516 | &retlen, (char *)&h1) < 0) | |
1da177e4 LT |
517 | return -1; |
518 | } else { | |
519 | #if 0 | |
520 | /* if erase mark present, need to skip it when doing check */ | |
521 | for (i = 0; i < nftl->EraseSize; i += SECTORSIZE) { | |
522 | /* check free sector */ | |
523 | if (check_free_sectors (nftl, block * nftl->EraseSize + i, | |
524 | SECTORSIZE, 0) != 0) | |
525 | return -1; | |
526 | ||
8593fbc6 | 527 | if (nftl_read_oob(mtd, block * nftl->EraseSize + i, |
f4a43cfc | 528 | 16, &retlen, buf) < 0) |
1da177e4 LT |
529 | return -1; |
530 | if (i == SECTORSIZE) { | |
531 | /* skip erase mark */ | |
532 | if (memcmpb(buf, 0xff, 8)) | |
533 | return -1; | |
534 | } else { | |
535 | if (memcmpb(buf, 0xff, 16)) | |
536 | return -1; | |
537 | } | |
538 | } | |
539 | #endif | |
540 | } | |
541 | ||
542 | return 0; | |
543 | } | |
544 | ||
545 | /* get_fold_mark: Read fold mark from Unit Control Information #2, we use FOLD_MARK_IN_PROGRESS | |
546 | * to indicate that we are in the progression of a Virtual Unit Chain folding. If the UCI #2 | |
547 | * is FOLD_MARK_IN_PROGRESS when mounting the NFTL, the (previous) folding process is interrupted | |
92394b5c | 548 | * for some reason. A clean up/check of the VUC is necessary in this case. |
1da177e4 LT |
549 | * |
550 | * WARNING: return 0 if read error | |
551 | */ | |
552 | static int get_fold_mark(struct NFTLrecord *nftl, unsigned int block) | |
553 | { | |
f4a43cfc | 554 | struct mtd_info *mtd = nftl->mbd.mtd; |
1da177e4 LT |
555 | struct nftl_uci2 uci; |
556 | size_t retlen; | |
557 | ||
8593fbc6 | 558 | if (nftl_read_oob(mtd, block * nftl->EraseSize + 2 * SECTORSIZE + 8, |
f4a43cfc | 559 | 8, &retlen, (char *)&uci) < 0) |
1da177e4 LT |
560 | return 0; |
561 | ||
562 | return le16_to_cpu((uci.FoldMark | uci.FoldMark1)); | |
563 | } | |
564 | ||
565 | int NFTL_mount(struct NFTLrecord *s) | |
566 | { | |
567 | int i; | |
fb60e87d | 568 | unsigned int first_logical_block, logical_block, rep_block, erase_mark; |
1da177e4 LT |
569 | unsigned int block, first_block, is_first_block; |
570 | int chain_length, do_format_chain; | |
571 | struct nftl_uci0 h0; | |
572 | struct nftl_uci1 h1; | |
f4a43cfc | 573 | struct mtd_info *mtd = s->mbd.mtd; |
1da177e4 LT |
574 | size_t retlen; |
575 | ||
576 | /* search for NFTL MediaHeader and Spare NFTL Media Header */ | |
577 | if (find_boot_record(s) < 0) { | |
578 | printk("Could not find valid boot record\n"); | |
579 | return -1; | |
580 | } | |
581 | ||
582 | /* init the logical to physical table */ | |
583 | for (i = 0; i < s->nb_blocks; i++) { | |
584 | s->EUNtable[i] = BLOCK_NIL; | |
585 | } | |
586 | ||
587 | /* first pass : explore each block chain */ | |
588 | first_logical_block = 0; | |
589 | for (first_block = 0; first_block < s->nb_blocks; first_block++) { | |
590 | /* if the block was not already explored, we can look at it */ | |
591 | if (s->ReplUnitTable[first_block] == BLOCK_NOTEXPLORED) { | |
592 | block = first_block; | |
593 | chain_length = 0; | |
594 | do_format_chain = 0; | |
595 | ||
596 | for (;;) { | |
597 | /* read the block header. If error, we format the chain */ | |
8593fbc6 | 598 | if (nftl_read_oob(mtd, |
f4a43cfc TG |
599 | block * s->EraseSize + 8, 8, |
600 | &retlen, (char *)&h0) < 0 || | |
8593fbc6 | 601 | nftl_read_oob(mtd, |
f4a43cfc TG |
602 | block * s->EraseSize + |
603 | SECTORSIZE + 8, 8, | |
604 | &retlen, (char *)&h1) < 0) { | |
1da177e4 LT |
605 | s->ReplUnitTable[block] = BLOCK_NIL; |
606 | do_format_chain = 1; | |
607 | break; | |
608 | } | |
609 | ||
610 | logical_block = le16_to_cpu ((h0.VirtUnitNum | h0.SpareVirtUnitNum)); | |
611 | rep_block = le16_to_cpu ((h0.ReplUnitNum | h0.SpareReplUnitNum)); | |
1da177e4 LT |
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, | |
92394b5c | 660 | but we need to read it completely */ |
1da177e4 LT |
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, | |
92394b5c | 672 | but we need to read it completely */ |
1da177e4 LT |
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 | } |