1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * inftlcore.c -- Linux driver for Inverse Flash Translation Layer (INFTL) |
4 | * |
5 | * Copyright © 2002, Greg Ungerer (gerg@snapgear.com) |
6 | * |
7 | * Based heavily on the nftlcore.c code which is: |
8 | * Copyright © 1999 Machine Vision Holdings, Inc. |
9 | * Copyright © 1999 David Woodhouse <dwmw2@infradead.org> |
10 | */ |
11 | |
12 | #include <linux/kernel.h> |
13 | #include <linux/module.h> |
14 | #include <linux/delay.h> |
15 | #include <linux/slab.h> |
16 | #include <linux/sched.h> |
17 | #include <linux/init.h> |
18 | #include <linux/kmod.h> |
19 | #include <linux/hdreg.h> |
20 | #include <linux/mtd/mtd.h> |
21 | #include <linux/mtd/nftl.h> |
22 | #include <linux/mtd/inftl.h> |
23 | #include <linux/mtd/rawnand.h> |
24 | #include <linux/uaccess.h> |
25 | #include <asm/errno.h> |
26 | #include <asm/io.h> |
27 | |
28 | /* |
29 | * Maximum number of loops while examining next block, to have a |
30 | * chance to detect consistency problems (they should never happen |
31 | * because of the checks done in the mounting. |
32 | */ |
33 | #define MAX_LOOPS 10000 |
34 | |
35 | static void inftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) |
36 | { |
37 | struct INFTLrecord *inftl; |
38 | unsigned long temp; |
39 | |
40 | if (!mtd_type_is_nand(mtd) || mtd->size > UINT_MAX) |
41 | return; |
42 | /* OK, this is moderately ugly. But probably safe. Alternatives? */ |
43 | if (memcmp(p: mtd->name, q: "DiskOnChip" , size: 10)) |
44 | return; |
45 | |
46 | if (!mtd->_block_isbad) { |
47 | printk(KERN_ERR |
48 | "INFTL no longer supports the old DiskOnChip drivers loaded via docprobe.\n" |
49 | "Please use the new diskonchip driver under the NAND subsystem.\n" ); |
50 | return; |
51 | } |
52 | |
53 | pr_debug("INFTL: add_mtd for %s\n" , mtd->name); |
54 | |
55 | inftl = kzalloc(size: sizeof(*inftl), GFP_KERNEL); |
56 | |
57 | if (!inftl) |
58 | return; |
59 | |
60 | inftl->mbd.mtd = mtd; |
61 | inftl->mbd.devnum = -1; |
62 | |
63 | inftl->mbd.tr = tr; |
64 | |
65 | if (INFTL_mount(s: inftl) < 0) { |
66 | printk(KERN_WARNING "INFTL: could not mount device\n" ); |
67 | kfree(objp: inftl); |
68 | return; |
69 | } |
70 | |
71 | /* OK, it's a new one. Set up all the data structures. */ |
72 | |
73 | /* Calculate geometry */ |
74 | inftl->cylinders = 1024; |
75 | inftl->heads = 16; |
76 | |
77 | temp = inftl->cylinders * inftl->heads; |
78 | inftl->sectors = inftl->mbd.size / temp; |
79 | if (inftl->mbd.size % temp) { |
80 | inftl->sectors++; |
81 | temp = inftl->cylinders * inftl->sectors; |
82 | inftl->heads = inftl->mbd.size / temp; |
83 | |
84 | if (inftl->mbd.size % temp) { |
85 | inftl->heads++; |
86 | temp = inftl->heads * inftl->sectors; |
87 | inftl->cylinders = inftl->mbd.size / temp; |
88 | } |
89 | } |
90 | |
91 | if (inftl->mbd.size != inftl->heads * inftl->cylinders * inftl->sectors) { |
92 | /* |
93 | Oh no we don't have |
94 | mbd.size == heads * cylinders * sectors |
95 | */ |
96 | printk(KERN_WARNING "INFTL: cannot calculate a geometry to " |
97 | "match size of 0x%lx.\n" , inftl->mbd.size); |
98 | printk(KERN_WARNING "INFTL: using C:%d H:%d S:%d " |
99 | "(== 0x%lx sects)\n" , |
100 | inftl->cylinders, inftl->heads , inftl->sectors, |
101 | (long)inftl->cylinders * (long)inftl->heads * |
102 | (long)inftl->sectors ); |
103 | } |
104 | |
105 | if (add_mtd_blktrans_dev(dev: &inftl->mbd)) { |
106 | kfree(objp: inftl->PUtable); |
107 | kfree(objp: inftl->VUtable); |
108 | kfree(objp: inftl); |
109 | return; |
110 | } |
111 | #ifdef PSYCHO_DEBUG |
112 | printk(KERN_INFO "INFTL: Found new inftl%c\n" , inftl->mbd.devnum + 'a'); |
113 | #endif |
114 | return; |
115 | } |
116 | |
117 | static void inftl_remove_dev(struct mtd_blktrans_dev *dev) |
118 | { |
119 | struct INFTLrecord *inftl = (void *)dev; |
120 | |
121 | pr_debug("INFTL: remove_dev (i=%d)\n" , dev->devnum); |
122 | |
123 | del_mtd_blktrans_dev(dev); |
124 | |
125 | kfree(objp: inftl->PUtable); |
126 | kfree(objp: inftl->VUtable); |
127 | } |
128 | |
129 | /* |
130 | * Actual INFTL access routines. |
131 | */ |
132 | |
133 | /* |
134 | * Read oob data from flash |
135 | */ |
136 | int inftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len, |
137 | size_t *retlen, uint8_t *buf) |
138 | { |
139 | struct mtd_oob_ops ops = { }; |
140 | int res; |
141 | |
142 | ops.mode = MTD_OPS_PLACE_OOB; |
143 | ops.ooboffs = offs & (mtd->writesize - 1); |
144 | ops.ooblen = len; |
145 | ops.oobbuf = buf; |
146 | ops.datbuf = NULL; |
147 | |
148 | res = mtd_read_oob(mtd, from: offs & ~(mtd->writesize - 1), ops: &ops); |
149 | *retlen = ops.oobretlen; |
150 | return res; |
151 | } |
152 | |
153 | /* |
154 | * Write oob data to flash |
155 | */ |
156 | int inftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len, |
157 | size_t *retlen, uint8_t *buf) |
158 | { |
159 | struct mtd_oob_ops ops = { }; |
160 | int res; |
161 | |
162 | ops.mode = MTD_OPS_PLACE_OOB; |
163 | ops.ooboffs = offs & (mtd->writesize - 1); |
164 | ops.ooblen = len; |
165 | ops.oobbuf = buf; |
166 | ops.datbuf = NULL; |
167 | |
168 | res = mtd_write_oob(mtd, to: offs & ~(mtd->writesize - 1), ops: &ops); |
169 | *retlen = ops.oobretlen; |
170 | return res; |
171 | } |
172 | |
173 | /* |
174 | * Write data and oob to flash |
175 | */ |
176 | static int inftl_write(struct mtd_info *mtd, loff_t offs, size_t len, |
177 | size_t *retlen, uint8_t *buf, uint8_t *oob) |
178 | { |
179 | struct mtd_oob_ops ops = { }; |
180 | int res; |
181 | |
182 | ops.mode = MTD_OPS_PLACE_OOB; |
183 | ops.ooboffs = offs; |
184 | ops.ooblen = mtd->oobsize; |
185 | ops.oobbuf = oob; |
186 | ops.datbuf = buf; |
187 | ops.len = len; |
188 | |
189 | res = mtd_write_oob(mtd, to: offs & ~(mtd->writesize - 1), ops: &ops); |
190 | *retlen = ops.retlen; |
191 | return res; |
192 | } |
193 | |
194 | /* |
195 | * INFTL_findfreeblock: Find a free Erase Unit on the INFTL partition. |
196 | * This function is used when the give Virtual Unit Chain. |
197 | */ |
198 | static u16 INFTL_findfreeblock(struct INFTLrecord *inftl, int desperate) |
199 | { |
200 | u16 pot = inftl->LastFreeEUN; |
201 | int silly = inftl->nb_blocks; |
202 | |
203 | pr_debug("INFTL: INFTL_findfreeblock(inftl=%p,desperate=%d)\n" , |
204 | inftl, desperate); |
205 | |
206 | /* |
207 | * Normally, we force a fold to happen before we run out of free |
208 | * blocks completely. |
209 | */ |
210 | if (!desperate && inftl->numfreeEUNs < 2) { |
211 | pr_debug("INFTL: there are too few free EUNs (%d)\n" , |
212 | inftl->numfreeEUNs); |
213 | return BLOCK_NIL; |
214 | } |
215 | |
216 | /* Scan for a free block */ |
217 | do { |
218 | if (inftl->PUtable[pot] == BLOCK_FREE) { |
219 | inftl->LastFreeEUN = pot; |
220 | return pot; |
221 | } |
222 | |
223 | if (++pot > inftl->lastEUN) |
224 | pot = 0; |
225 | |
226 | if (!silly--) { |
227 | printk(KERN_WARNING "INFTL: no free blocks found! " |
228 | "EUN range = %d - %d\n" , 0, inftl->LastFreeEUN); |
229 | return BLOCK_NIL; |
230 | } |
231 | } while (pot != inftl->LastFreeEUN); |
232 | |
233 | return BLOCK_NIL; |
234 | } |
235 | |
236 | static u16 INFTL_foldchain(struct INFTLrecord *inftl, unsigned thisVUC, unsigned pendingblock) |
237 | { |
238 | u16 BlockMap[MAX_SECTORS_PER_UNIT]; |
239 | unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT]; |
240 | unsigned int thisEUN, prevEUN, status; |
241 | struct mtd_info *mtd = inftl->mbd.mtd; |
242 | int block, silly; |
243 | unsigned int targetEUN; |
244 | struct inftl_oob oob; |
245 | size_t retlen; |
246 | |
247 | pr_debug("INFTL: INFTL_foldchain(inftl=%p,thisVUC=%d,pending=%d)\n" , |
248 | inftl, thisVUC, pendingblock); |
249 | |
250 | memset(BlockMap, 0xff, sizeof(BlockMap)); |
251 | memset(BlockDeleted, 0, sizeof(BlockDeleted)); |
252 | |
253 | thisEUN = targetEUN = inftl->VUtable[thisVUC]; |
254 | |
255 | if (thisEUN == BLOCK_NIL) { |
256 | printk(KERN_WARNING "INFTL: trying to fold non-existent " |
257 | "Virtual Unit Chain %d!\n" , thisVUC); |
258 | return BLOCK_NIL; |
259 | } |
260 | |
261 | /* |
262 | * Scan to find the Erase Unit which holds the actual data for each |
263 | * 512-byte block within the Chain. |
264 | */ |
265 | silly = MAX_LOOPS; |
266 | while (thisEUN < inftl->nb_blocks) { |
267 | for (block = 0; block < inftl->EraseSize/SECTORSIZE; block ++) { |
268 | if ((BlockMap[block] != BLOCK_NIL) || |
269 | BlockDeleted[block]) |
270 | continue; |
271 | |
272 | if (inftl_read_oob(mtd, offs: (thisEUN * inftl->EraseSize) |
273 | + (block * SECTORSIZE), len: 16, retlen: &retlen, |
274 | buf: (char *)&oob) < 0) |
275 | status = SECTOR_IGNORE; |
276 | else |
277 | status = oob.b.Status | oob.b.Status1; |
278 | |
279 | switch(status) { |
280 | case SECTOR_FREE: |
281 | case SECTOR_IGNORE: |
282 | break; |
283 | case SECTOR_USED: |
284 | BlockMap[block] = thisEUN; |
285 | continue; |
286 | case SECTOR_DELETED: |
287 | BlockDeleted[block] = 1; |
288 | continue; |
289 | default: |
290 | printk(KERN_WARNING "INFTL: unknown status " |
291 | "for block %d in EUN %d: %x\n" , |
292 | block, thisEUN, status); |
293 | break; |
294 | } |
295 | } |
296 | |
297 | if (!silly--) { |
298 | printk(KERN_WARNING "INFTL: infinite loop in Virtual " |
299 | "Unit Chain 0x%x\n" , thisVUC); |
300 | return BLOCK_NIL; |
301 | } |
302 | |
303 | thisEUN = inftl->PUtable[thisEUN]; |
304 | } |
305 | |
306 | /* |
307 | * OK. We now know the location of every block in the Virtual Unit |
308 | * Chain, and the Erase Unit into which we are supposed to be copying. |
309 | * Go for it. |
310 | */ |
311 | pr_debug("INFTL: folding chain %d into unit %d\n" , thisVUC, targetEUN); |
312 | |
313 | for (block = 0; block < inftl->EraseSize/SECTORSIZE ; block++) { |
314 | unsigned char movebuf[SECTORSIZE]; |
315 | int ret; |
316 | |
317 | /* |
318 | * If it's in the target EUN already, or if it's pending write, |
319 | * do nothing. |
320 | */ |
321 | if (BlockMap[block] == targetEUN || (pendingblock == |
322 | (thisVUC * (inftl->EraseSize / SECTORSIZE) + block))) { |
323 | continue; |
324 | } |
325 | |
326 | /* |
327 | * Copy only in non free block (free blocks can only |
328 | * happen in case of media errors or deleted blocks). |
329 | */ |
330 | if (BlockMap[block] == BLOCK_NIL) |
331 | continue; |
332 | |
333 | ret = mtd_read(mtd, |
334 | from: (inftl->EraseSize * BlockMap[block]) + (block * SECTORSIZE), |
335 | SECTORSIZE, |
336 | retlen: &retlen, |
337 | buf: movebuf); |
338 | if (ret < 0 && !mtd_is_bitflip(err: ret)) { |
339 | ret = mtd_read(mtd, |
340 | from: (inftl->EraseSize * BlockMap[block]) + (block * SECTORSIZE), |
341 | SECTORSIZE, |
342 | retlen: &retlen, |
343 | buf: movebuf); |
344 | if (ret != -EIO) |
345 | pr_debug("INFTL: error went away on retry?\n" ); |
346 | } |
347 | memset(&oob, 0xff, sizeof(struct inftl_oob)); |
348 | oob.b.Status = oob.b.Status1 = SECTOR_USED; |
349 | |
350 | inftl_write(mtd: inftl->mbd.mtd, offs: (inftl->EraseSize * targetEUN) + |
351 | (block * SECTORSIZE), SECTORSIZE, retlen: &retlen, |
352 | buf: movebuf, oob: (char *)&oob); |
353 | } |
354 | |
355 | /* |
356 | * Newest unit in chain now contains data from _all_ older units. |
357 | * So go through and erase each unit in chain, oldest first. (This |
358 | * is important, by doing oldest first if we crash/reboot then it |
359 | * is relatively simple to clean up the mess). |
360 | */ |
361 | pr_debug("INFTL: want to erase virtual chain %d\n" , thisVUC); |
362 | |
363 | for (;;) { |
364 | /* Find oldest unit in chain. */ |
365 | thisEUN = inftl->VUtable[thisVUC]; |
366 | prevEUN = BLOCK_NIL; |
367 | while (inftl->PUtable[thisEUN] != BLOCK_NIL) { |
368 | prevEUN = thisEUN; |
369 | thisEUN = inftl->PUtable[thisEUN]; |
370 | } |
371 | |
372 | /* Check if we are all done */ |
373 | if (thisEUN == targetEUN) |
374 | break; |
375 | |
376 | /* Unlink the last block from the chain. */ |
377 | inftl->PUtable[prevEUN] = BLOCK_NIL; |
378 | |
379 | /* Now try to erase it. */ |
380 | if (INFTL_formatblock(s: inftl, block: thisEUN) < 0) { |
381 | /* |
382 | * Could not erase : mark block as reserved. |
383 | */ |
384 | inftl->PUtable[thisEUN] = BLOCK_RESERVED; |
385 | } else { |
386 | /* Correctly erased : mark it as free */ |
387 | inftl->PUtable[thisEUN] = BLOCK_FREE; |
388 | inftl->numfreeEUNs++; |
389 | } |
390 | } |
391 | |
392 | return targetEUN; |
393 | } |
394 | |
395 | static u16 INFTL_makefreeblock(struct INFTLrecord *inftl, unsigned pendingblock) |
396 | { |
397 | /* |
398 | * This is the part that needs some cleverness applied. |
399 | * For now, I'm doing the minimum applicable to actually |
400 | * get the thing to work. |
401 | * Wear-levelling and other clever stuff needs to be implemented |
402 | * and we also need to do some assessment of the results when |
403 | * the system loses power half-way through the routine. |
404 | */ |
405 | u16 LongestChain = 0; |
406 | u16 ChainLength = 0, thislen; |
407 | u16 chain, EUN; |
408 | |
409 | pr_debug("INFTL: INFTL_makefreeblock(inftl=%p," |
410 | "pending=%d)\n" , inftl, pendingblock); |
411 | |
412 | for (chain = 0; chain < inftl->nb_blocks; chain++) { |
413 | EUN = inftl->VUtable[chain]; |
414 | thislen = 0; |
415 | |
416 | while (EUN <= inftl->lastEUN) { |
417 | thislen++; |
418 | EUN = inftl->PUtable[EUN]; |
419 | if (thislen > 0xff00) { |
420 | printk(KERN_WARNING "INFTL: endless loop in " |
421 | "Virtual Chain %d: Unit %x\n" , |
422 | chain, EUN); |
423 | /* |
424 | * Actually, don't return failure. |
425 | * Just ignore this chain and get on with it. |
426 | */ |
427 | thislen = 0; |
428 | break; |
429 | } |
430 | } |
431 | |
432 | if (thislen > ChainLength) { |
433 | ChainLength = thislen; |
434 | LongestChain = chain; |
435 | } |
436 | } |
437 | |
438 | if (ChainLength < 2) { |
439 | printk(KERN_WARNING "INFTL: no Virtual Unit Chains available " |
440 | "for folding. Failing request\n" ); |
441 | return BLOCK_NIL; |
442 | } |
443 | |
444 | return INFTL_foldchain(inftl, thisVUC: LongestChain, pendingblock); |
445 | } |
446 | |
447 | static int nrbits(unsigned int val, int bitcount) |
448 | { |
449 | int i, total = 0; |
450 | |
451 | for (i = 0; (i < bitcount); i++) |
452 | total += (((0x1 << i) & val) ? 1 : 0); |
453 | return total; |
454 | } |
455 | |
456 | /* |
457 | * INFTL_findwriteunit: Return the unit number into which we can write |
458 | * for this block. Make it available if it isn't already. |
459 | */ |
460 | static inline u16 INFTL_findwriteunit(struct INFTLrecord *inftl, unsigned block) |
461 | { |
462 | unsigned int thisVUC = block / (inftl->EraseSize / SECTORSIZE); |
463 | unsigned int thisEUN, writeEUN, prev_block, status; |
464 | unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize -1); |
465 | struct mtd_info *mtd = inftl->mbd.mtd; |
466 | struct inftl_oob oob; |
467 | struct inftl_bci bci; |
468 | unsigned char anac, nacs, parity; |
469 | size_t retlen; |
470 | int silly, silly2 = 3; |
471 | |
472 | pr_debug("INFTL: INFTL_findwriteunit(inftl=%p,block=%d)\n" , |
473 | inftl, block); |
474 | |
475 | do { |
476 | /* |
477 | * Scan the media to find a unit in the VUC which has |
478 | * a free space for the block in question. |
479 | */ |
480 | writeEUN = BLOCK_NIL; |
481 | thisEUN = inftl->VUtable[thisVUC]; |
482 | silly = MAX_LOOPS; |
483 | |
484 | while (thisEUN <= inftl->lastEUN) { |
485 | inftl_read_oob(mtd, offs: (thisEUN * inftl->EraseSize) + |
486 | blockofs, len: 8, retlen: &retlen, buf: (char *)&bci); |
487 | |
488 | status = bci.Status | bci.Status1; |
489 | pr_debug("INFTL: status of block %d in EUN %d is %x\n" , |
490 | block , writeEUN, status); |
491 | |
492 | switch(status) { |
493 | case SECTOR_FREE: |
494 | writeEUN = thisEUN; |
495 | break; |
496 | case SECTOR_DELETED: |
497 | case SECTOR_USED: |
498 | /* Can't go any further */ |
499 | goto hitused; |
500 | case SECTOR_IGNORE: |
501 | break; |
502 | default: |
503 | /* |
504 | * Invalid block. Don't use it any more. |
505 | * Must implement. |
506 | */ |
507 | break; |
508 | } |
509 | |
510 | if (!silly--) { |
511 | printk(KERN_WARNING "INFTL: infinite loop in " |
512 | "Virtual Unit Chain 0x%x\n" , thisVUC); |
513 | return BLOCK_NIL; |
514 | } |
515 | |
516 | /* Skip to next block in chain */ |
517 | thisEUN = inftl->PUtable[thisEUN]; |
518 | } |
519 | |
520 | hitused: |
521 | if (writeEUN != BLOCK_NIL) |
522 | return writeEUN; |
523 | |
524 | |
525 | /* |
526 | * OK. We didn't find one in the existing chain, or there |
527 | * is no existing chain. Allocate a new one. |
528 | */ |
529 | writeEUN = INFTL_findfreeblock(inftl, desperate: 0); |
530 | |
531 | if (writeEUN == BLOCK_NIL) { |
532 | /* |
533 | * That didn't work - there were no free blocks just |
534 | * waiting to be picked up. We're going to have to fold |
535 | * a chain to make room. |
536 | */ |
537 | thisEUN = INFTL_makefreeblock(inftl, pendingblock: block); |
538 | |
539 | /* |
540 | * Hopefully we free something, lets try again. |
541 | * This time we are desperate... |
542 | */ |
543 | pr_debug("INFTL: using desperate==1 to find free EUN " |
544 | "to accommodate write to VUC %d\n" , |
545 | thisVUC); |
546 | writeEUN = INFTL_findfreeblock(inftl, desperate: 1); |
547 | if (writeEUN == BLOCK_NIL) { |
548 | /* |
549 | * Ouch. This should never happen - we should |
550 | * always be able to make some room somehow. |
551 | * If we get here, we've allocated more storage |
552 | * space than actual media, or our makefreeblock |
553 | * routine is missing something. |
554 | */ |
555 | printk(KERN_WARNING "INFTL: cannot make free " |
556 | "space.\n" ); |
557 | #ifdef DEBUG |
558 | INFTL_dumptables(inftl); |
559 | INFTL_dumpVUchains(inftl); |
560 | #endif |
561 | return BLOCK_NIL; |
562 | } |
563 | } |
564 | |
565 | /* |
566 | * Insert new block into virtual chain. Firstly update the |
567 | * block headers in flash... |
568 | */ |
569 | anac = 0; |
570 | nacs = 0; |
571 | thisEUN = inftl->VUtable[thisVUC]; |
572 | if (thisEUN != BLOCK_NIL) { |
573 | inftl_read_oob(mtd, offs: thisEUN * inftl->EraseSize |
574 | + 8, len: 8, retlen: &retlen, buf: (char *)&oob.u); |
575 | anac = oob.u.a.ANAC + 1; |
576 | nacs = oob.u.a.NACs + 1; |
577 | } |
578 | |
579 | prev_block = inftl->VUtable[thisVUC]; |
580 | if (prev_block < inftl->nb_blocks) |
581 | prev_block -= inftl->firstEUN; |
582 | |
583 | parity = (nrbits(val: thisVUC, bitcount: 16) & 0x1) ? 0x1 : 0; |
584 | parity |= (nrbits(val: prev_block, bitcount: 16) & 0x1) ? 0x2 : 0; |
585 | parity |= (nrbits(val: anac, bitcount: 8) & 0x1) ? 0x4 : 0; |
586 | parity |= (nrbits(val: nacs, bitcount: 8) & 0x1) ? 0x8 : 0; |
587 | |
588 | oob.u.a.virtualUnitNo = cpu_to_le16(thisVUC); |
589 | oob.u.a.prevUnitNo = cpu_to_le16(prev_block); |
590 | oob.u.a.ANAC = anac; |
591 | oob.u.a.NACs = nacs; |
592 | oob.u.a.parityPerField = parity; |
593 | oob.u.a.discarded = 0xaa; |
594 | |
595 | inftl_write_oob(mtd, offs: writeEUN * inftl->EraseSize + 8, len: 8, |
596 | retlen: &retlen, buf: (char *)&oob.u); |
597 | |
598 | /* Also back up header... */ |
599 | oob.u.b.virtualUnitNo = cpu_to_le16(thisVUC); |
600 | oob.u.b.prevUnitNo = cpu_to_le16(prev_block); |
601 | oob.u.b.ANAC = anac; |
602 | oob.u.b.NACs = nacs; |
603 | oob.u.b.parityPerField = parity; |
604 | oob.u.b.discarded = 0xaa; |
605 | |
606 | inftl_write_oob(mtd, offs: writeEUN * inftl->EraseSize + |
607 | SECTORSIZE * 4 + 8, len: 8, retlen: &retlen, buf: (char *)&oob.u); |
608 | |
609 | inftl->PUtable[writeEUN] = inftl->VUtable[thisVUC]; |
610 | inftl->VUtable[thisVUC] = writeEUN; |
611 | |
612 | inftl->numfreeEUNs--; |
613 | return writeEUN; |
614 | |
615 | } while (silly2--); |
616 | |
617 | printk(KERN_WARNING "INFTL: error folding to make room for Virtual " |
618 | "Unit Chain 0x%x\n" , thisVUC); |
619 | return BLOCK_NIL; |
620 | } |
621 | |
622 | /* |
623 | * Given a Virtual Unit Chain, see if it can be deleted, and if so do it. |
624 | */ |
625 | static void INFTL_trydeletechain(struct INFTLrecord *inftl, unsigned thisVUC) |
626 | { |
627 | struct mtd_info *mtd = inftl->mbd.mtd; |
628 | unsigned char BlockUsed[MAX_SECTORS_PER_UNIT]; |
629 | unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT]; |
630 | unsigned int thisEUN, status; |
631 | int block, silly; |
632 | struct inftl_bci bci; |
633 | size_t retlen; |
634 | |
635 | pr_debug("INFTL: INFTL_trydeletechain(inftl=%p," |
636 | "thisVUC=%d)\n" , inftl, thisVUC); |
637 | |
638 | memset(BlockUsed, 0, sizeof(BlockUsed)); |
639 | memset(BlockDeleted, 0, sizeof(BlockDeleted)); |
640 | |
641 | thisEUN = inftl->VUtable[thisVUC]; |
642 | if (thisEUN == BLOCK_NIL) { |
643 | printk(KERN_WARNING "INFTL: trying to delete non-existent " |
644 | "Virtual Unit Chain %d!\n" , thisVUC); |
645 | return; |
646 | } |
647 | |
648 | /* |
649 | * Scan through the Erase Units to determine whether any data is in |
650 | * each of the 512-byte blocks within the Chain. |
651 | */ |
652 | silly = MAX_LOOPS; |
653 | while (thisEUN < inftl->nb_blocks) { |
654 | for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++) { |
655 | if (BlockUsed[block] || BlockDeleted[block]) |
656 | continue; |
657 | |
658 | if (inftl_read_oob(mtd, offs: (thisEUN * inftl->EraseSize) |
659 | + (block * SECTORSIZE), len: 8 , retlen: &retlen, |
660 | buf: (char *)&bci) < 0) |
661 | status = SECTOR_IGNORE; |
662 | else |
663 | status = bci.Status | bci.Status1; |
664 | |
665 | switch(status) { |
666 | case SECTOR_FREE: |
667 | case SECTOR_IGNORE: |
668 | break; |
669 | case SECTOR_USED: |
670 | BlockUsed[block] = 1; |
671 | continue; |
672 | case SECTOR_DELETED: |
673 | BlockDeleted[block] = 1; |
674 | continue; |
675 | default: |
676 | printk(KERN_WARNING "INFTL: unknown status " |
677 | "for block %d in EUN %d: 0x%x\n" , |
678 | block, thisEUN, status); |
679 | } |
680 | } |
681 | |
682 | if (!silly--) { |
683 | printk(KERN_WARNING "INFTL: infinite loop in Virtual " |
684 | "Unit Chain 0x%x\n" , thisVUC); |
685 | return; |
686 | } |
687 | |
688 | thisEUN = inftl->PUtable[thisEUN]; |
689 | } |
690 | |
691 | for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++) |
692 | if (BlockUsed[block]) |
693 | return; |
694 | |
695 | /* |
696 | * For each block in the chain free it and make it available |
697 | * for future use. Erase from the oldest unit first. |
698 | */ |
699 | pr_debug("INFTL: deleting empty VUC %d\n" , thisVUC); |
700 | |
701 | for (;;) { |
702 | u16 *prevEUN = &inftl->VUtable[thisVUC]; |
703 | thisEUN = *prevEUN; |
704 | |
705 | /* If the chain is all gone already, we're done */ |
706 | if (thisEUN == BLOCK_NIL) { |
707 | pr_debug("INFTL: Empty VUC %d for deletion was already absent\n" , thisEUN); |
708 | return; |
709 | } |
710 | |
711 | /* Find oldest unit in chain. */ |
712 | while (inftl->PUtable[thisEUN] != BLOCK_NIL) { |
713 | BUG_ON(thisEUN >= inftl->nb_blocks); |
714 | |
715 | prevEUN = &inftl->PUtable[thisEUN]; |
716 | thisEUN = *prevEUN; |
717 | } |
718 | |
719 | pr_debug("Deleting EUN %d from VUC %d\n" , |
720 | thisEUN, thisVUC); |
721 | |
722 | if (INFTL_formatblock(s: inftl, block: thisEUN) < 0) { |
723 | /* |
724 | * Could not erase : mark block as reserved. |
725 | */ |
726 | inftl->PUtable[thisEUN] = BLOCK_RESERVED; |
727 | } else { |
728 | /* Correctly erased : mark it as free */ |
729 | inftl->PUtable[thisEUN] = BLOCK_FREE; |
730 | inftl->numfreeEUNs++; |
731 | } |
732 | |
733 | /* Now sort out whatever was pointing to it... */ |
734 | *prevEUN = BLOCK_NIL; |
735 | |
736 | /* Ideally we'd actually be responsive to new |
737 | requests while we're doing this -- if there's |
738 | free space why should others be made to wait? */ |
739 | cond_resched(); |
740 | } |
741 | |
742 | inftl->VUtable[thisVUC] = BLOCK_NIL; |
743 | } |
744 | |
745 | static int INFTL_deleteblock(struct INFTLrecord *inftl, unsigned block) |
746 | { |
747 | unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)]; |
748 | unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); |
749 | struct mtd_info *mtd = inftl->mbd.mtd; |
750 | unsigned int status; |
751 | int silly = MAX_LOOPS; |
752 | size_t retlen; |
753 | struct inftl_bci bci; |
754 | |
755 | pr_debug("INFTL: INFTL_deleteblock(inftl=%p," |
756 | "block=%d)\n" , inftl, block); |
757 | |
758 | while (thisEUN < inftl->nb_blocks) { |
759 | if (inftl_read_oob(mtd, offs: (thisEUN * inftl->EraseSize) + |
760 | blockofs, len: 8, retlen: &retlen, buf: (char *)&bci) < 0) |
761 | status = SECTOR_IGNORE; |
762 | else |
763 | status = bci.Status | bci.Status1; |
764 | |
765 | switch (status) { |
766 | case SECTOR_FREE: |
767 | case SECTOR_IGNORE: |
768 | break; |
769 | case SECTOR_DELETED: |
770 | thisEUN = BLOCK_NIL; |
771 | goto foundit; |
772 | case SECTOR_USED: |
773 | goto foundit; |
774 | default: |
775 | printk(KERN_WARNING "INFTL: unknown status for " |
776 | "block %d in EUN %d: 0x%x\n" , |
777 | block, thisEUN, status); |
778 | break; |
779 | } |
780 | |
781 | if (!silly--) { |
782 | printk(KERN_WARNING "INFTL: infinite loop in Virtual " |
783 | "Unit Chain 0x%x\n" , |
784 | block / (inftl->EraseSize / SECTORSIZE)); |
785 | return 1; |
786 | } |
787 | thisEUN = inftl->PUtable[thisEUN]; |
788 | } |
789 | |
790 | foundit: |
791 | if (thisEUN != BLOCK_NIL) { |
792 | loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs; |
793 | |
794 | if (inftl_read_oob(mtd, offs: ptr, len: 8, retlen: &retlen, buf: (char *)&bci) < 0) |
795 | return -EIO; |
796 | bci.Status = bci.Status1 = SECTOR_DELETED; |
797 | if (inftl_write_oob(mtd, offs: ptr, len: 8, retlen: &retlen, buf: (char *)&bci) < 0) |
798 | return -EIO; |
799 | INFTL_trydeletechain(inftl, thisVUC: block / (inftl->EraseSize / SECTORSIZE)); |
800 | } |
801 | return 0; |
802 | } |
803 | |
804 | static int inftl_writeblock(struct mtd_blktrans_dev *mbd, unsigned long block, |
805 | char *buffer) |
806 | { |
807 | struct INFTLrecord *inftl = (void *)mbd; |
808 | unsigned int writeEUN; |
809 | unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); |
810 | size_t retlen; |
811 | struct inftl_oob oob; |
812 | char *p, *pend; |
813 | |
814 | pr_debug("INFTL: inftl_writeblock(inftl=%p,block=%ld," |
815 | "buffer=%p)\n" , inftl, block, buffer); |
816 | |
817 | /* Is block all zero? */ |
818 | pend = buffer + SECTORSIZE; |
819 | for (p = buffer; p < pend && !*p; p++) |
820 | ; |
821 | |
822 | if (p < pend) { |
823 | writeEUN = INFTL_findwriteunit(inftl, block); |
824 | |
825 | if (writeEUN == BLOCK_NIL) { |
826 | printk(KERN_WARNING "inftl_writeblock(): cannot find " |
827 | "block to write to\n" ); |
828 | /* |
829 | * If we _still_ haven't got a block to use, |
830 | * we're screwed. |
831 | */ |
832 | return 1; |
833 | } |
834 | |
835 | memset(&oob, 0xff, sizeof(struct inftl_oob)); |
836 | oob.b.Status = oob.b.Status1 = SECTOR_USED; |
837 | |
838 | inftl_write(mtd: inftl->mbd.mtd, offs: (writeEUN * inftl->EraseSize) + |
839 | blockofs, SECTORSIZE, retlen: &retlen, buf: (char *)buffer, |
840 | oob: (char *)&oob); |
841 | /* |
842 | * need to write SECTOR_USED flags since they are not written |
843 | * in mtd_writeecc |
844 | */ |
845 | } else { |
846 | INFTL_deleteblock(inftl, block); |
847 | } |
848 | |
849 | return 0; |
850 | } |
851 | |
852 | static int inftl_readblock(struct mtd_blktrans_dev *mbd, unsigned long block, |
853 | char *buffer) |
854 | { |
855 | struct INFTLrecord *inftl = (void *)mbd; |
856 | unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)]; |
857 | unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1); |
858 | struct mtd_info *mtd = inftl->mbd.mtd; |
859 | unsigned int status; |
860 | int silly = MAX_LOOPS; |
861 | struct inftl_bci bci; |
862 | size_t retlen; |
863 | |
864 | pr_debug("INFTL: inftl_readblock(inftl=%p,block=%ld," |
865 | "buffer=%p)\n" , inftl, block, buffer); |
866 | |
867 | while (thisEUN < inftl->nb_blocks) { |
868 | if (inftl_read_oob(mtd, offs: (thisEUN * inftl->EraseSize) + |
869 | blockofs, len: 8, retlen: &retlen, buf: (char *)&bci) < 0) |
870 | status = SECTOR_IGNORE; |
871 | else |
872 | status = bci.Status | bci.Status1; |
873 | |
874 | switch (status) { |
875 | case SECTOR_DELETED: |
876 | thisEUN = BLOCK_NIL; |
877 | goto foundit; |
878 | case SECTOR_USED: |
879 | goto foundit; |
880 | case SECTOR_FREE: |
881 | case SECTOR_IGNORE: |
882 | break; |
883 | default: |
884 | printk(KERN_WARNING "INFTL: unknown status for " |
885 | "block %ld in EUN %d: 0x%04x\n" , |
886 | block, thisEUN, status); |
887 | break; |
888 | } |
889 | |
890 | if (!silly--) { |
891 | printk(KERN_WARNING "INFTL: infinite loop in " |
892 | "Virtual Unit Chain 0x%lx\n" , |
893 | block / (inftl->EraseSize / SECTORSIZE)); |
894 | return 1; |
895 | } |
896 | |
897 | thisEUN = inftl->PUtable[thisEUN]; |
898 | } |
899 | |
900 | foundit: |
901 | if (thisEUN == BLOCK_NIL) { |
902 | /* The requested block is not on the media, return all 0x00 */ |
903 | memset(buffer, 0, SECTORSIZE); |
904 | } else { |
905 | size_t retlen; |
906 | loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs; |
907 | int ret = mtd_read(mtd, from: ptr, SECTORSIZE, retlen: &retlen, buf: buffer); |
908 | |
909 | /* Handle corrected bit flips gracefully */ |
910 | if (ret < 0 && !mtd_is_bitflip(err: ret)) |
911 | return -EIO; |
912 | } |
913 | return 0; |
914 | } |
915 | |
916 | static int inftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo) |
917 | { |
918 | struct INFTLrecord *inftl = (void *)dev; |
919 | |
920 | geo->heads = inftl->heads; |
921 | geo->sectors = inftl->sectors; |
922 | geo->cylinders = inftl->cylinders; |
923 | |
924 | return 0; |
925 | } |
926 | |
927 | static struct mtd_blktrans_ops inftl_tr = { |
928 | .name = "inftl" , |
929 | .major = INFTL_MAJOR, |
930 | .part_bits = INFTL_PARTN_BITS, |
931 | .blksize = 512, |
932 | .getgeo = inftl_getgeo, |
933 | .readsect = inftl_readblock, |
934 | .writesect = inftl_writeblock, |
935 | .add_mtd = inftl_add_mtd, |
936 | .remove_dev = inftl_remove_dev, |
937 | .owner = THIS_MODULE, |
938 | }; |
939 | |
940 | module_mtd_blktrans(inftl_tr); |
941 | |
942 | MODULE_LICENSE("GPL" ); |
943 | MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>, David Woodhouse <dwmw2@infradead.org>, Fabrice Bellard <fabrice.bellard@netgem.com> et al." ); |
944 | MODULE_DESCRIPTION("Support code for Inverse Flash Translation Layer, used on M-Systems DiskOnChip 2000, Millennium and Millennium Plus" ); |
945 | |