Commit | Line | Data |
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1da177e4 LT |
1 | /* Linux driver for NAND Flash Translation Layer */ |
2 | /* (c) 1999 Machine Vision Holdings, Inc. */ | |
3 | /* Author: David Woodhouse <dwmw2@infradead.org> */ | |
97894cda | 4 | /* $Id: nftlcore.c,v 1.98 2005/11/07 11:14:21 gleixner Exp $ */ |
1da177e4 LT |
5 | |
6 | /* | |
7 | The contents of this file are distributed under the GNU General | |
8 | Public License version 2. The author places no additional | |
9 | restrictions of any kind on it. | |
10 | */ | |
11 | ||
12 | #define PRERELEASE | |
13 | ||
14 | #include <linux/config.h> | |
15 | #include <linux/kernel.h> | |
16 | #include <linux/module.h> | |
17 | #include <asm/errno.h> | |
18 | #include <asm/io.h> | |
19 | #include <asm/uaccess.h> | |
20 | #include <linux/miscdevice.h> | |
21 | #include <linux/pci.h> | |
22 | #include <linux/delay.h> | |
23 | #include <linux/slab.h> | |
24 | #include <linux/sched.h> | |
25 | #include <linux/init.h> | |
26 | #include <linux/hdreg.h> | |
27 | ||
28 | #include <linux/kmod.h> | |
29 | #include <linux/mtd/mtd.h> | |
30 | #include <linux/mtd/nand.h> | |
31 | #include <linux/mtd/nftl.h> | |
32 | #include <linux/mtd/blktrans.h> | |
33 | ||
34 | /* maximum number of loops while examining next block, to have a | |
35 | chance to detect consistency problems (they should never happen | |
36 | because of the checks done in the mounting */ | |
37 | ||
38 | #define MAX_LOOPS 10000 | |
39 | ||
40 | ||
41 | static void nftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) | |
42 | { | |
43 | struct NFTLrecord *nftl; | |
44 | unsigned long temp; | |
45 | ||
46 | if (mtd->type != MTD_NANDFLASH) | |
47 | return; | |
48 | /* OK, this is moderately ugly. But probably safe. Alternatives? */ | |
49 | if (memcmp(mtd->name, "DiskOnChip", 10)) | |
50 | return; | |
51 | ||
52 | if (!mtd->block_isbad) { | |
53 | printk(KERN_ERR | |
54 | "NFTL no longer supports the old DiskOnChip drivers loaded via docprobe.\n" | |
55 | "Please use the new diskonchip driver under the NAND subsystem.\n"); | |
56 | return; | |
57 | } | |
58 | ||
59 | DEBUG(MTD_DEBUG_LEVEL1, "NFTL: add_mtd for %s\n", mtd->name); | |
60 | ||
61 | nftl = kmalloc(sizeof(struct NFTLrecord), GFP_KERNEL); | |
62 | ||
63 | if (!nftl) { | |
64 | printk(KERN_WARNING "NFTL: out of memory for data structures\n"); | |
65 | return; | |
66 | } | |
67 | memset(nftl, 0, sizeof(*nftl)); | |
68 | ||
69 | nftl->mbd.mtd = mtd; | |
70 | nftl->mbd.devnum = -1; | |
71 | nftl->mbd.blksize = 512; | |
72 | nftl->mbd.tr = tr; | |
73 | memcpy(&nftl->oobinfo, &mtd->oobinfo, sizeof(struct nand_oobinfo)); | |
74 | nftl->oobinfo.useecc = MTD_NANDECC_PLACEONLY; | |
75 | ||
76 | if (NFTL_mount(nftl) < 0) { | |
77 | printk(KERN_WARNING "NFTL: could not mount device\n"); | |
78 | kfree(nftl); | |
79 | return; | |
80 | } | |
81 | ||
82 | /* OK, it's a new one. Set up all the data structures. */ | |
83 | ||
84 | /* Calculate geometry */ | |
85 | nftl->cylinders = 1024; | |
86 | nftl->heads = 16; | |
87 | ||
88 | temp = nftl->cylinders * nftl->heads; | |
89 | nftl->sectors = nftl->mbd.size / temp; | |
90 | if (nftl->mbd.size % temp) { | |
91 | nftl->sectors++; | |
92 | temp = nftl->cylinders * nftl->sectors; | |
93 | nftl->heads = nftl->mbd.size / temp; | |
94 | ||
95 | if (nftl->mbd.size % temp) { | |
96 | nftl->heads++; | |
97 | temp = nftl->heads * nftl->sectors; | |
98 | nftl->cylinders = nftl->mbd.size / temp; | |
99 | } | |
100 | } | |
101 | ||
102 | if (nftl->mbd.size != nftl->heads * nftl->cylinders * nftl->sectors) { | |
103 | /* | |
97894cda | 104 | Oh no we don't have |
1da177e4 LT |
105 | mbd.size == heads * cylinders * sectors |
106 | */ | |
107 | printk(KERN_WARNING "NFTL: cannot calculate a geometry to " | |
108 | "match size of 0x%lx.\n", nftl->mbd.size); | |
109 | printk(KERN_WARNING "NFTL: using C:%d H:%d S:%d " | |
110 | "(== 0x%lx sects)\n", | |
97894cda | 111 | nftl->cylinders, nftl->heads , nftl->sectors, |
1da177e4 LT |
112 | (long)nftl->cylinders * (long)nftl->heads * |
113 | (long)nftl->sectors ); | |
114 | } | |
115 | ||
116 | if (add_mtd_blktrans_dev(&nftl->mbd)) { | |
117 | if (nftl->ReplUnitTable) | |
118 | kfree(nftl->ReplUnitTable); | |
119 | if (nftl->EUNtable) | |
120 | kfree(nftl->EUNtable); | |
121 | kfree(nftl); | |
122 | return; | |
123 | } | |
124 | #ifdef PSYCHO_DEBUG | |
125 | printk(KERN_INFO "NFTL: Found new nftl%c\n", nftl->mbd.devnum + 'a'); | |
126 | #endif | |
127 | } | |
128 | ||
129 | static void nftl_remove_dev(struct mtd_blktrans_dev *dev) | |
130 | { | |
131 | struct NFTLrecord *nftl = (void *)dev; | |
132 | ||
133 | DEBUG(MTD_DEBUG_LEVEL1, "NFTL: remove_dev (i=%d)\n", dev->devnum); | |
134 | ||
135 | del_mtd_blktrans_dev(dev); | |
136 | if (nftl->ReplUnitTable) | |
137 | kfree(nftl->ReplUnitTable); | |
138 | if (nftl->EUNtable) | |
139 | kfree(nftl->EUNtable); | |
140 | kfree(nftl); | |
141 | } | |
142 | ||
143 | #ifdef CONFIG_NFTL_RW | |
144 | ||
145 | /* Actual NFTL access routines */ | |
146 | /* NFTL_findfreeblock: Find a free Erase Unit on the NFTL partition. This function is used | |
147 | * when the give Virtual Unit Chain | |
148 | */ | |
149 | static u16 NFTL_findfreeblock(struct NFTLrecord *nftl, int desperate ) | |
150 | { | |
151 | /* For a given Virtual Unit Chain: find or create a free block and | |
152 | add it to the chain */ | |
153 | /* We're passed the number of the last EUN in the chain, to save us from | |
154 | having to look it up again */ | |
155 | u16 pot = nftl->LastFreeEUN; | |
156 | int silly = nftl->nb_blocks; | |
157 | ||
158 | /* Normally, we force a fold to happen before we run out of free blocks completely */ | |
159 | if (!desperate && nftl->numfreeEUNs < 2) { | |
160 | DEBUG(MTD_DEBUG_LEVEL1, "NFTL_findfreeblock: there are too few free EUNs\n"); | |
161 | return 0xffff; | |
162 | } | |
163 | ||
164 | /* Scan for a free block */ | |
165 | do { | |
166 | if (nftl->ReplUnitTable[pot] == BLOCK_FREE) { | |
167 | nftl->LastFreeEUN = pot; | |
168 | nftl->numfreeEUNs--; | |
169 | return pot; | |
170 | } | |
171 | ||
172 | /* This will probably point to the MediaHdr unit itself, | |
173 | right at the beginning of the partition. But that unit | |
174 | (and the backup unit too) should have the UCI set | |
175 | up so that it's not selected for overwriting */ | |
176 | if (++pot > nftl->lastEUN) | |
177 | pot = le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN); | |
178 | ||
179 | if (!silly--) { | |
180 | printk("Argh! No free blocks found! LastFreeEUN = %d, " | |
97894cda | 181 | "FirstEUN = %d\n", nftl->LastFreeEUN, |
1da177e4 LT |
182 | le16_to_cpu(nftl->MediaHdr.FirstPhysicalEUN)); |
183 | return 0xffff; | |
184 | } | |
185 | } while (pot != nftl->LastFreeEUN); | |
186 | ||
187 | return 0xffff; | |
188 | } | |
189 | ||
190 | static u16 NFTL_foldchain (struct NFTLrecord *nftl, unsigned thisVUC, unsigned pendingblock ) | |
191 | { | |
192 | u16 BlockMap[MAX_SECTORS_PER_UNIT]; | |
193 | unsigned char BlockLastState[MAX_SECTORS_PER_UNIT]; | |
194 | unsigned char BlockFreeFound[MAX_SECTORS_PER_UNIT]; | |
195 | unsigned int thisEUN; | |
196 | int block; | |
197 | int silly; | |
198 | unsigned int targetEUN; | |
199 | struct nftl_oob oob; | |
200 | int inplace = 1; | |
201 | size_t retlen; | |
202 | ||
203 | memset(BlockMap, 0xff, sizeof(BlockMap)); | |
204 | memset(BlockFreeFound, 0, sizeof(BlockFreeFound)); | |
205 | ||
206 | thisEUN = nftl->EUNtable[thisVUC]; | |
207 | ||
208 | if (thisEUN == BLOCK_NIL) { | |
209 | printk(KERN_WARNING "Trying to fold non-existent " | |
210 | "Virtual Unit Chain %d!\n", thisVUC); | |
211 | return BLOCK_NIL; | |
212 | } | |
97894cda | 213 | |
1da177e4 LT |
214 | /* Scan to find the Erase Unit which holds the actual data for each |
215 | 512-byte block within the Chain. | |
216 | */ | |
217 | silly = MAX_LOOPS; | |
218 | targetEUN = BLOCK_NIL; | |
219 | while (thisEUN <= nftl->lastEUN ) { | |
220 | unsigned int status, foldmark; | |
221 | ||
222 | targetEUN = thisEUN; | |
223 | for (block = 0; block < nftl->EraseSize / 512; block ++) { | |
224 | MTD_READOOB(nftl->mbd.mtd, | |
225 | (thisEUN * nftl->EraseSize) + (block * 512), | |
226 | 16 , &retlen, (char *)&oob); | |
227 | if (block == 2) { | |
228 | foldmark = oob.u.c.FoldMark | oob.u.c.FoldMark1; | |
229 | if (foldmark == FOLD_MARK_IN_PROGRESS) { | |
97894cda | 230 | DEBUG(MTD_DEBUG_LEVEL1, |
1da177e4 LT |
231 | "Write Inhibited on EUN %d\n", thisEUN); |
232 | inplace = 0; | |
233 | } else { | |
234 | /* There's no other reason not to do inplace, | |
235 | except ones that come later. So we don't need | |
236 | to preserve inplace */ | |
237 | inplace = 1; | |
238 | } | |
239 | } | |
240 | status = oob.b.Status | oob.b.Status1; | |
241 | BlockLastState[block] = status; | |
242 | ||
243 | switch(status) { | |
244 | case SECTOR_FREE: | |
245 | BlockFreeFound[block] = 1; | |
246 | break; | |
247 | ||
248 | case SECTOR_USED: | |
249 | if (!BlockFreeFound[block]) | |
250 | BlockMap[block] = thisEUN; | |
251 | else | |
97894cda | 252 | printk(KERN_WARNING |
1da177e4 LT |
253 | "SECTOR_USED found after SECTOR_FREE " |
254 | "in Virtual Unit Chain %d for block %d\n", | |
255 | thisVUC, block); | |
256 | break; | |
257 | case SECTOR_DELETED: | |
258 | if (!BlockFreeFound[block]) | |
259 | BlockMap[block] = BLOCK_NIL; | |
260 | else | |
97894cda | 261 | printk(KERN_WARNING |
1da177e4 LT |
262 | "SECTOR_DELETED found after SECTOR_FREE " |
263 | "in Virtual Unit Chain %d for block %d\n", | |
264 | thisVUC, block); | |
265 | break; | |
266 | ||
267 | case SECTOR_IGNORE: | |
268 | break; | |
269 | default: | |
270 | printk("Unknown status for block %d in EUN %d: %x\n", | |
271 | block, thisEUN, status); | |
272 | } | |
273 | } | |
274 | ||
275 | if (!silly--) { | |
276 | printk(KERN_WARNING "Infinite loop in Virtual Unit Chain 0x%x\n", | |
277 | thisVUC); | |
278 | return BLOCK_NIL; | |
279 | } | |
97894cda | 280 | |
1da177e4 LT |
281 | thisEUN = nftl->ReplUnitTable[thisEUN]; |
282 | } | |
283 | ||
284 | if (inplace) { | |
285 | /* We're being asked to be a fold-in-place. Check | |
286 | that all blocks which actually have data associated | |
97894cda | 287 | with them (i.e. BlockMap[block] != BLOCK_NIL) are |
1da177e4 LT |
288 | either already present or SECTOR_FREE in the target |
289 | block. If not, we're going to have to fold out-of-place | |
290 | anyway. | |
291 | */ | |
292 | for (block = 0; block < nftl->EraseSize / 512 ; block++) { | |
293 | if (BlockLastState[block] != SECTOR_FREE && | |
294 | BlockMap[block] != BLOCK_NIL && | |
295 | BlockMap[block] != targetEUN) { | |
296 | DEBUG(MTD_DEBUG_LEVEL1, "Setting inplace to 0. VUC %d, " | |
297 | "block %d was %x lastEUN, " | |
298 | "and is in EUN %d (%s) %d\n", | |
299 | thisVUC, block, BlockLastState[block], | |
97894cda | 300 | BlockMap[block], |
1da177e4 LT |
301 | BlockMap[block]== targetEUN ? "==" : "!=", |
302 | targetEUN); | |
303 | inplace = 0; | |
304 | break; | |
305 | } | |
306 | } | |
307 | ||
308 | if (pendingblock >= (thisVUC * (nftl->EraseSize / 512)) && | |
309 | pendingblock < ((thisVUC + 1)* (nftl->EraseSize / 512)) && | |
310 | BlockLastState[pendingblock - (thisVUC * (nftl->EraseSize / 512))] != | |
311 | SECTOR_FREE) { | |
312 | DEBUG(MTD_DEBUG_LEVEL1, "Pending write not free in EUN %d. " | |
313 | "Folding out of place.\n", targetEUN); | |
314 | inplace = 0; | |
315 | } | |
316 | } | |
97894cda | 317 | |
1da177e4 LT |
318 | if (!inplace) { |
319 | DEBUG(MTD_DEBUG_LEVEL1, "Cannot fold Virtual Unit Chain %d in place. " | |
320 | "Trying out-of-place\n", thisVUC); | |
321 | /* We need to find a targetEUN to fold into. */ | |
322 | targetEUN = NFTL_findfreeblock(nftl, 1); | |
323 | if (targetEUN == BLOCK_NIL) { | |
97894cda | 324 | /* Ouch. Now we're screwed. We need to do a |
1da177e4 LT |
325 | fold-in-place of another chain to make room |
326 | for this one. We need a better way of selecting | |
97894cda | 327 | which chain to fold, because makefreeblock will |
1da177e4 LT |
328 | only ask us to fold the same one again. |
329 | */ | |
330 | printk(KERN_WARNING | |
331 | "NFTL_findfreeblock(desperate) returns 0xffff.\n"); | |
332 | return BLOCK_NIL; | |
333 | } | |
334 | } else { | |
335 | /* We put a fold mark in the chain we are folding only if | |
336 | we fold in place to help the mount check code. If we do | |
337 | not fold in place, it is possible to find the valid | |
338 | chain by selecting the longer one */ | |
339 | oob.u.c.FoldMark = oob.u.c.FoldMark1 = cpu_to_le16(FOLD_MARK_IN_PROGRESS); | |
340 | oob.u.c.unused = 0xffffffff; | |
97894cda | 341 | MTD_WRITEOOB(nftl->mbd.mtd, (nftl->EraseSize * targetEUN) + 2 * 512 + 8, |
1da177e4 LT |
342 | 8, &retlen, (char *)&oob.u); |
343 | } | |
344 | ||
345 | /* OK. We now know the location of every block in the Virtual Unit Chain, | |
346 | and the Erase Unit into which we are supposed to be copying. | |
347 | Go for it. | |
348 | */ | |
349 | DEBUG(MTD_DEBUG_LEVEL1,"Folding chain %d into unit %d\n", thisVUC, targetEUN); | |
350 | for (block = 0; block < nftl->EraseSize / 512 ; block++) { | |
351 | unsigned char movebuf[512]; | |
352 | int ret; | |
353 | ||
354 | /* If it's in the target EUN already, or if it's pending write, do nothing */ | |
355 | if (BlockMap[block] == targetEUN || | |
356 | (pendingblock == (thisVUC * (nftl->EraseSize / 512) + block))) { | |
357 | continue; | |
358 | } | |
359 | ||
360 | /* copy only in non free block (free blocks can only | |
361 | happen in case of media errors or deleted blocks) */ | |
362 | if (BlockMap[block] == BLOCK_NIL) | |
363 | continue; | |
97894cda | 364 | |
1da177e4 | 365 | ret = MTD_READ(nftl->mbd.mtd, (nftl->EraseSize * BlockMap[block]) + (block * 512), |
97894cda | 366 | 512, &retlen, movebuf); |
1da177e4 LT |
367 | if (ret < 0) { |
368 | ret = MTD_READ(nftl->mbd.mtd, (nftl->EraseSize * BlockMap[block]) | |
369 | + (block * 512), 512, &retlen, | |
97894cda TG |
370 | movebuf); |
371 | if (ret != -EIO) | |
1da177e4 LT |
372 | printk("Error went away on retry.\n"); |
373 | } | |
374 | memset(&oob, 0xff, sizeof(struct nftl_oob)); | |
375 | oob.b.Status = oob.b.Status1 = SECTOR_USED; | |
376 | MTD_WRITEECC(nftl->mbd.mtd, (nftl->EraseSize * targetEUN) + (block * 512), | |
377 | 512, &retlen, movebuf, (char *)&oob, &nftl->oobinfo); | |
378 | } | |
97894cda | 379 | |
1da177e4 LT |
380 | /* add the header so that it is now a valid chain */ |
381 | oob.u.a.VirtUnitNum = oob.u.a.SpareVirtUnitNum | |
382 | = cpu_to_le16(thisVUC); | |
383 | oob.u.a.ReplUnitNum = oob.u.a.SpareReplUnitNum = 0xffff; | |
97894cda TG |
384 | |
385 | MTD_WRITEOOB(nftl->mbd.mtd, (nftl->EraseSize * targetEUN) + 8, | |
1da177e4 LT |
386 | 8, &retlen, (char *)&oob.u); |
387 | ||
388 | /* OK. We've moved the whole lot into the new block. Now we have to free the original blocks. */ | |
389 | ||
97894cda | 390 | /* At this point, we have two different chains for this Virtual Unit, and no way to tell |
1da177e4 LT |
391 | them apart. If we crash now, we get confused. However, both contain the same data, so we |
392 | shouldn't actually lose data in this case. It's just that when we load up on a medium which | |
393 | has duplicate chains, we need to free one of the chains because it's not necessary any more. | |
394 | */ | |
395 | thisEUN = nftl->EUNtable[thisVUC]; | |
396 | DEBUG(MTD_DEBUG_LEVEL1,"Want to erase\n"); | |
397 | ||
97894cda | 398 | /* For each block in the old chain (except the targetEUN of course), |
1da177e4 LT |
399 | free it and make it available for future use */ |
400 | while (thisEUN <= nftl->lastEUN && thisEUN != targetEUN) { | |
401 | unsigned int EUNtmp; | |
402 | ||
403 | EUNtmp = nftl->ReplUnitTable[thisEUN]; | |
404 | ||
405 | if (NFTL_formatblock(nftl, thisEUN) < 0) { | |
406 | /* could not erase : mark block as reserved | |
407 | */ | |
408 | nftl->ReplUnitTable[thisEUN] = BLOCK_RESERVED; | |
409 | } else { | |
410 | /* correctly erased : mark it as free */ | |
411 | nftl->ReplUnitTable[thisEUN] = BLOCK_FREE; | |
412 | nftl->numfreeEUNs++; | |
413 | } | |
414 | thisEUN = EUNtmp; | |
415 | } | |
97894cda | 416 | |
1da177e4 LT |
417 | /* Make this the new start of chain for thisVUC */ |
418 | nftl->ReplUnitTable[targetEUN] = BLOCK_NIL; | |
419 | nftl->EUNtable[thisVUC] = targetEUN; | |
420 | ||
421 | return targetEUN; | |
422 | } | |
423 | ||
424 | static u16 NFTL_makefreeblock( struct NFTLrecord *nftl , unsigned pendingblock) | |
425 | { | |
97894cda | 426 | /* This is the part that needs some cleverness applied. |
1da177e4 LT |
427 | For now, I'm doing the minimum applicable to actually |
428 | get the thing to work. | |
429 | Wear-levelling and other clever stuff needs to be implemented | |
430 | and we also need to do some assessment of the results when | |
431 | the system loses power half-way through the routine. | |
432 | */ | |
433 | u16 LongestChain = 0; | |
434 | u16 ChainLength = 0, thislen; | |
435 | u16 chain, EUN; | |
436 | ||
437 | for (chain = 0; chain < le32_to_cpu(nftl->MediaHdr.FormattedSize) / nftl->EraseSize; chain++) { | |
438 | EUN = nftl->EUNtable[chain]; | |
439 | thislen = 0; | |
440 | ||
441 | while (EUN <= nftl->lastEUN) { | |
442 | thislen++; | |
443 | //printk("VUC %d reaches len %d with EUN %d\n", chain, thislen, EUN); | |
444 | EUN = nftl->ReplUnitTable[EUN] & 0x7fff; | |
445 | if (thislen > 0xff00) { | |
446 | printk("Endless loop in Virtual Chain %d: Unit %x\n", | |
447 | chain, EUN); | |
448 | } | |
449 | if (thislen > 0xff10) { | |
450 | /* Actually, don't return failure. Just ignore this chain and | |
451 | get on with it. */ | |
452 | thislen = 0; | |
453 | break; | |
454 | } | |
455 | } | |
456 | ||
457 | if (thislen > ChainLength) { | |
458 | //printk("New longest chain is %d with length %d\n", chain, thislen); | |
459 | ChainLength = thislen; | |
460 | LongestChain = chain; | |
461 | } | |
462 | } | |
463 | ||
464 | if (ChainLength < 2) { | |
465 | printk(KERN_WARNING "No Virtual Unit Chains available for folding. " | |
466 | "Failing request\n"); | |
467 | return 0xffff; | |
468 | } | |
469 | ||
470 | return NFTL_foldchain (nftl, LongestChain, pendingblock); | |
471 | } | |
472 | ||
97894cda | 473 | /* NFTL_findwriteunit: Return the unit number into which we can write |
1da177e4 LT |
474 | for this block. Make it available if it isn't already |
475 | */ | |
476 | static inline u16 NFTL_findwriteunit(struct NFTLrecord *nftl, unsigned block) | |
477 | { | |
478 | u16 lastEUN; | |
479 | u16 thisVUC = block / (nftl->EraseSize / 512); | |
480 | unsigned int writeEUN; | |
481 | unsigned long blockofs = (block * 512) & (nftl->EraseSize -1); | |
482 | size_t retlen; | |
483 | int silly, silly2 = 3; | |
484 | struct nftl_oob oob; | |
485 | ||
486 | do { | |
487 | /* Scan the media to find a unit in the VUC which has | |
488 | a free space for the block in question. | |
489 | */ | |
490 | ||
97894cda | 491 | /* This condition catches the 0x[7f]fff cases, as well as |
1da177e4 LT |
492 | being a sanity check for past-end-of-media access |
493 | */ | |
494 | lastEUN = BLOCK_NIL; | |
495 | writeEUN = nftl->EUNtable[thisVUC]; | |
496 | silly = MAX_LOOPS; | |
497 | while (writeEUN <= nftl->lastEUN) { | |
498 | struct nftl_bci bci; | |
499 | size_t retlen; | |
500 | unsigned int status; | |
501 | ||
502 | lastEUN = writeEUN; | |
503 | ||
504 | MTD_READOOB(nftl->mbd.mtd, (writeEUN * nftl->EraseSize) + blockofs, | |
505 | 8, &retlen, (char *)&bci); | |
97894cda | 506 | |
1da177e4 LT |
507 | DEBUG(MTD_DEBUG_LEVEL2, "Status of block %d in EUN %d is %x\n", |
508 | block , writeEUN, le16_to_cpu(bci.Status)); | |
509 | ||
510 | status = bci.Status | bci.Status1; | |
511 | switch(status) { | |
512 | case SECTOR_FREE: | |
513 | return writeEUN; | |
514 | ||
515 | case SECTOR_DELETED: | |
516 | case SECTOR_USED: | |
517 | case SECTOR_IGNORE: | |
518 | break; | |
519 | default: | |
520 | // Invalid block. Don't use it any more. Must implement. | |
97894cda | 521 | break; |
1da177e4 | 522 | } |
97894cda TG |
523 | |
524 | if (!silly--) { | |
1da177e4 LT |
525 | printk(KERN_WARNING |
526 | "Infinite loop in Virtual Unit Chain 0x%x\n", | |
527 | thisVUC); | |
528 | return 0xffff; | |
529 | } | |
530 | ||
531 | /* Skip to next block in chain */ | |
532 | writeEUN = nftl->ReplUnitTable[writeEUN]; | |
533 | } | |
534 | ||
97894cda | 535 | /* OK. We didn't find one in the existing chain, or there |
1da177e4 LT |
536 | is no existing chain. */ |
537 | ||
538 | /* Try to find an already-free block */ | |
539 | writeEUN = NFTL_findfreeblock(nftl, 0); | |
540 | ||
541 | if (writeEUN == BLOCK_NIL) { | |
542 | /* That didn't work - there were no free blocks just | |
543 | waiting to be picked up. We're going to have to fold | |
544 | a chain to make room. | |
545 | */ | |
546 | ||
547 | /* First remember the start of this chain */ | |
548 | //u16 startEUN = nftl->EUNtable[thisVUC]; | |
97894cda | 549 | |
1da177e4 LT |
550 | //printk("Write to VirtualUnitChain %d, calling makefreeblock()\n", thisVUC); |
551 | writeEUN = NFTL_makefreeblock(nftl, 0xffff); | |
552 | ||
553 | if (writeEUN == BLOCK_NIL) { | |
97894cda | 554 | /* OK, we accept that the above comment is |
1da177e4 LT |
555 | lying - there may have been free blocks |
556 | last time we called NFTL_findfreeblock(), | |
557 | but they are reserved for when we're | |
558 | desperate. Well, now we're desperate. | |
559 | */ | |
560 | DEBUG(MTD_DEBUG_LEVEL1, "Using desperate==1 to find free EUN to accommodate write to VUC %d\n", thisVUC); | |
561 | writeEUN = NFTL_findfreeblock(nftl, 1); | |
562 | } | |
563 | if (writeEUN == BLOCK_NIL) { | |
564 | /* Ouch. This should never happen - we should | |
97894cda TG |
565 | always be able to make some room somehow. |
566 | If we get here, we've allocated more storage | |
1da177e4 LT |
567 | space than actual media, or our makefreeblock |
568 | routine is missing something. | |
569 | */ | |
570 | printk(KERN_WARNING "Cannot make free space.\n"); | |
571 | return BLOCK_NIL; | |
97894cda | 572 | } |
1da177e4 LT |
573 | //printk("Restarting scan\n"); |
574 | lastEUN = BLOCK_NIL; | |
575 | continue; | |
576 | } | |
577 | ||
578 | /* We've found a free block. Insert it into the chain. */ | |
97894cda | 579 | |
1da177e4 LT |
580 | if (lastEUN != BLOCK_NIL) { |
581 | thisVUC |= 0x8000; /* It's a replacement block */ | |
582 | } else { | |
583 | /* The first block in a new chain */ | |
584 | nftl->EUNtable[thisVUC] = writeEUN; | |
585 | } | |
586 | ||
587 | /* set up the actual EUN we're writing into */ | |
588 | /* Both in our cache... */ | |
589 | nftl->ReplUnitTable[writeEUN] = BLOCK_NIL; | |
590 | ||
591 | /* ... and on the flash itself */ | |
592 | MTD_READOOB(nftl->mbd.mtd, writeEUN * nftl->EraseSize + 8, 8, | |
593 | &retlen, (char *)&oob.u); | |
594 | ||
595 | oob.u.a.VirtUnitNum = oob.u.a.SpareVirtUnitNum = cpu_to_le16(thisVUC); | |
596 | ||
597 | MTD_WRITEOOB(nftl->mbd.mtd, writeEUN * nftl->EraseSize + 8, 8, | |
598 | &retlen, (char *)&oob.u); | |
599 | ||
600 | /* we link the new block to the chain only after the | |
601 | block is ready. It avoids the case where the chain | |
602 | could point to a free block */ | |
603 | if (lastEUN != BLOCK_NIL) { | |
604 | /* Both in our cache... */ | |
605 | nftl->ReplUnitTable[lastEUN] = writeEUN; | |
606 | /* ... and on the flash itself */ | |
607 | MTD_READOOB(nftl->mbd.mtd, (lastEUN * nftl->EraseSize) + 8, | |
608 | 8, &retlen, (char *)&oob.u); | |
609 | ||
610 | oob.u.a.ReplUnitNum = oob.u.a.SpareReplUnitNum | |
611 | = cpu_to_le16(writeEUN); | |
612 | ||
613 | MTD_WRITEOOB(nftl->mbd.mtd, (lastEUN * nftl->EraseSize) + 8, | |
614 | 8, &retlen, (char *)&oob.u); | |
615 | } | |
616 | ||
617 | return writeEUN; | |
618 | ||
619 | } while (silly2--); | |
620 | ||
621 | printk(KERN_WARNING "Error folding to make room for Virtual Unit Chain 0x%x\n", | |
622 | thisVUC); | |
623 | return 0xffff; | |
624 | } | |
625 | ||
626 | static int nftl_writeblock(struct mtd_blktrans_dev *mbd, unsigned long block, | |
627 | char *buffer) | |
628 | { | |
629 | struct NFTLrecord *nftl = (void *)mbd; | |
630 | u16 writeEUN; | |
631 | unsigned long blockofs = (block * 512) & (nftl->EraseSize - 1); | |
632 | size_t retlen; | |
633 | struct nftl_oob oob; | |
634 | ||
635 | writeEUN = NFTL_findwriteunit(nftl, block); | |
636 | ||
637 | if (writeEUN == BLOCK_NIL) { | |
638 | printk(KERN_WARNING | |
639 | "NFTL_writeblock(): Cannot find block to write to\n"); | |
640 | /* If we _still_ haven't got a block to use, we're screwed */ | |
641 | return 1; | |
642 | } | |
643 | ||
644 | memset(&oob, 0xff, sizeof(struct nftl_oob)); | |
645 | oob.b.Status = oob.b.Status1 = SECTOR_USED; | |
646 | MTD_WRITEECC(nftl->mbd.mtd, (writeEUN * nftl->EraseSize) + blockofs, | |
647 | 512, &retlen, (char *)buffer, (char *)&oob, &nftl->oobinfo); | |
648 | /* need to write SECTOR_USED flags since they are not written in mtd_writeecc */ | |
649 | ||
650 | return 0; | |
651 | } | |
652 | #endif /* CONFIG_NFTL_RW */ | |
653 | ||
654 | static int nftl_readblock(struct mtd_blktrans_dev *mbd, unsigned long block, | |
655 | char *buffer) | |
656 | { | |
657 | struct NFTLrecord *nftl = (void *)mbd; | |
658 | u16 lastgoodEUN; | |
659 | u16 thisEUN = nftl->EUNtable[block / (nftl->EraseSize / 512)]; | |
660 | unsigned long blockofs = (block * 512) & (nftl->EraseSize - 1); | |
661 | unsigned int status; | |
662 | int silly = MAX_LOOPS; | |
663 | size_t retlen; | |
664 | struct nftl_bci bci; | |
665 | ||
666 | lastgoodEUN = BLOCK_NIL; | |
667 | ||
668 | if (thisEUN != BLOCK_NIL) { | |
669 | while (thisEUN < nftl->nb_blocks) { | |
670 | if (MTD_READOOB(nftl->mbd.mtd, (thisEUN * nftl->EraseSize) + blockofs, | |
671 | 8, &retlen, (char *)&bci) < 0) | |
672 | status = SECTOR_IGNORE; | |
673 | else | |
674 | status = bci.Status | bci.Status1; | |
675 | ||
676 | switch (status) { | |
677 | case SECTOR_FREE: | |
678 | /* no modification of a sector should follow a free sector */ | |
679 | goto the_end; | |
680 | case SECTOR_DELETED: | |
681 | lastgoodEUN = BLOCK_NIL; | |
682 | break; | |
683 | case SECTOR_USED: | |
684 | lastgoodEUN = thisEUN; | |
685 | break; | |
686 | case SECTOR_IGNORE: | |
687 | break; | |
688 | default: | |
689 | printk("Unknown status for block %ld in EUN %d: %x\n", | |
690 | block, thisEUN, status); | |
691 | break; | |
692 | } | |
693 | ||
694 | if (!silly--) { | |
695 | printk(KERN_WARNING "Infinite loop in Virtual Unit Chain 0x%lx\n", | |
696 | block / (nftl->EraseSize / 512)); | |
697 | return 1; | |
698 | } | |
699 | thisEUN = nftl->ReplUnitTable[thisEUN]; | |
700 | } | |
701 | } | |
702 | ||
703 | the_end: | |
704 | if (lastgoodEUN == BLOCK_NIL) { | |
705 | /* the requested block is not on the media, return all 0x00 */ | |
706 | memset(buffer, 0, 512); | |
707 | } else { | |
708 | loff_t ptr = (lastgoodEUN * nftl->EraseSize) + blockofs; | |
709 | size_t retlen; | |
710 | if (MTD_READ(nftl->mbd.mtd, ptr, 512, &retlen, buffer)) | |
711 | return -EIO; | |
712 | } | |
713 | return 0; | |
714 | } | |
715 | ||
716 | static int nftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) | |
717 | { | |
718 | struct NFTLrecord *nftl = (void *)dev; | |
719 | ||
720 | geo->heads = nftl->heads; | |
721 | geo->sectors = nftl->sectors; | |
722 | geo->cylinders = nftl->cylinders; | |
723 | ||
724 | return 0; | |
725 | } | |
726 | ||
727 | /**************************************************************************** | |
728 | * | |
729 | * Module stuff | |
730 | * | |
731 | ****************************************************************************/ | |
732 | ||
733 | ||
734 | static struct mtd_blktrans_ops nftl_tr = { | |
735 | .name = "nftl", | |
736 | .major = NFTL_MAJOR, | |
737 | .part_bits = NFTL_PARTN_BITS, | |
738 | .getgeo = nftl_getgeo, | |
739 | .readsect = nftl_readblock, | |
740 | #ifdef CONFIG_NFTL_RW | |
741 | .writesect = nftl_writeblock, | |
742 | #endif | |
743 | .add_mtd = nftl_add_mtd, | |
744 | .remove_dev = nftl_remove_dev, | |
745 | .owner = THIS_MODULE, | |
746 | }; | |
747 | ||
748 | extern char nftlmountrev[]; | |
749 | ||
750 | static int __init init_nftl(void) | |
751 | { | |
97894cda | 752 | printk(KERN_INFO "NFTL driver: nftlcore.c $Revision: 1.98 $, nftlmount.c %s\n", nftlmountrev); |
1da177e4 LT |
753 | |
754 | return register_mtd_blktrans(&nftl_tr); | |
755 | } | |
756 | ||
757 | static void __exit cleanup_nftl(void) | |
758 | { | |
759 | deregister_mtd_blktrans(&nftl_tr); | |
760 | } | |
761 | ||
762 | module_init(init_nftl); | |
763 | module_exit(cleanup_nftl); | |
764 | ||
765 | MODULE_LICENSE("GPL"); | |
766 | MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>, Fabrice Bellard <fabrice.bellard@netgem.com> et al."); | |
767 | MODULE_DESCRIPTION("Support code for NAND Flash Translation Layer, used on M-Systems DiskOnChip 2000 and Millennium"); |