blob: 73f05227dc8cb0607d11c6709a2233959f65d92a [file] [log] [blame]
Thomas Gleixner97894cd2005-11-07 11:15:26 +00001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * inftlcore.c -- Linux driver for Inverse Flash Translation Layer (INFTL)
3 *
4 * (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
5 *
6 * Based heavily on the nftlcore.c code which is:
7 * (c) 1999 Machine Vision Holdings, Inc.
8 * Author: David Woodhouse <dwmw2@infradead.org>
9 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/delay.h>
28#include <linux/slab.h>
29#include <linux/sched.h>
30#include <linux/init.h>
31#include <linux/kmod.h>
32#include <linux/hdreg.h>
33#include <linux/mtd/mtd.h>
34#include <linux/mtd/nftl.h>
35#include <linux/mtd/inftl.h>
Thomas Gleixner9223a452006-05-23 17:21:03 +020036#include <linux/mtd/nand.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <asm/uaccess.h>
38#include <asm/errno.h>
39#include <asm/io.h>
40
41/*
42 * Maximum number of loops while examining next block, to have a
43 * chance to detect consistency problems (they should never happen
44 * because of the checks done in the mounting.
45 */
46#define MAX_LOOPS 10000
47
Linus Torvalds1da177e2005-04-16 15:20:36 -070048static void inftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
49{
50 struct INFTLrecord *inftl;
51 unsigned long temp;
52
Adrian Hunter69423d92008-12-10 13:37:21 +000053 if (mtd->type != MTD_NANDFLASH || mtd->size > UINT_MAX)
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 return;
55 /* OK, this is moderately ugly. But probably safe. Alternatives? */
56 if (memcmp(mtd->name, "DiskOnChip", 10))
57 return;
58
59 if (!mtd->block_isbad) {
60 printk(KERN_ERR
61"INFTL no longer supports the old DiskOnChip drivers loaded via docprobe.\n"
62"Please use the new diskonchip driver under the NAND subsystem.\n");
63 return;
64 }
65
66 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: add_mtd for %s\n", mtd->name);
67
Burman Yan95b93a02006-11-15 21:10:29 +020068 inftl = kzalloc(sizeof(*inftl), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
70 if (!inftl) {
71 printk(KERN_WARNING "INFTL: Out of memory for data structures\n");
72 return;
73 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070074
75 inftl->mbd.mtd = mtd;
76 inftl->mbd.devnum = -1;
Richard Purdie19187672006-10-27 09:09:33 +010077
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 inftl->mbd.tr = tr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Thomas Gleixner9223a452006-05-23 17:21:03 +020080 if (INFTL_mount(inftl) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 printk(KERN_WARNING "INFTL: could not mount device\n");
82 kfree(inftl);
83 return;
Thomas Gleixner9223a452006-05-23 17:21:03 +020084 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
86 /* OK, it's a new one. Set up all the data structures. */
87
88 /* Calculate geometry */
89 inftl->cylinders = 1024;
90 inftl->heads = 16;
91
92 temp = inftl->cylinders * inftl->heads;
93 inftl->sectors = inftl->mbd.size / temp;
94 if (inftl->mbd.size % temp) {
95 inftl->sectors++;
96 temp = inftl->cylinders * inftl->sectors;
97 inftl->heads = inftl->mbd.size / temp;
98
99 if (inftl->mbd.size % temp) {
100 inftl->heads++;
101 temp = inftl->heads * inftl->sectors;
102 inftl->cylinders = inftl->mbd.size / temp;
103 }
104 }
105
106 if (inftl->mbd.size != inftl->heads * inftl->cylinders * inftl->sectors) {
107 /*
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000108 Oh no we don't have
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 mbd.size == heads * cylinders * sectors
110 */
111 printk(KERN_WARNING "INFTL: cannot calculate a geometry to "
112 "match size of 0x%lx.\n", inftl->mbd.size);
113 printk(KERN_WARNING "INFTL: using C:%d H:%d S:%d "
114 "(== 0x%lx sects)\n",
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000115 inftl->cylinders, inftl->heads , inftl->sectors,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 (long)inftl->cylinders * (long)inftl->heads *
117 (long)inftl->sectors );
118 }
119
120 if (add_mtd_blktrans_dev(&inftl->mbd)) {
Jesper Juhlfa671642005-11-07 01:01:27 -0800121 kfree(inftl->PUtable);
122 kfree(inftl->VUtable);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123 kfree(inftl);
124 return;
125 }
126#ifdef PSYCHO_DEBUG
Eric Sesterhenn / snakebyte8b68a122006-03-31 02:29:47 -0800127 printk(KERN_INFO "INFTL: Found new inftl%c\n", inftl->mbd.devnum + 'a');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128#endif
129 return;
130}
131
132static void inftl_remove_dev(struct mtd_blktrans_dev *dev)
133{
134 struct INFTLrecord *inftl = (void *)dev;
135
136 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: remove_dev (i=%d)\n", dev->devnum);
137
138 del_mtd_blktrans_dev(dev);
139
Jesper Juhlfa671642005-11-07 01:01:27 -0800140 kfree(inftl->PUtable);
141 kfree(inftl->VUtable);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 kfree(inftl);
143}
144
145/*
146 * Actual INFTL access routines.
147 */
148
149/*
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200150 * Read oob data from flash
151 */
152int inftl_read_oob(struct mtd_info *mtd, loff_t offs, size_t len,
153 size_t *retlen, uint8_t *buf)
154{
155 struct mtd_oob_ops ops;
156 int res;
157
158 ops.mode = MTD_OOB_PLACE;
159 ops.ooboffs = offs & (mtd->writesize - 1);
160 ops.ooblen = len;
161 ops.oobbuf = buf;
162 ops.datbuf = NULL;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200163
164 res = mtd->read_oob(mtd, offs & ~(mtd->writesize - 1), &ops);
Vitaly Wool70145682006-11-03 18:20:38 +0300165 *retlen = ops.oobretlen;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200166 return res;
167}
168
169/*
170 * Write oob data to flash
171 */
172int inftl_write_oob(struct mtd_info *mtd, loff_t offs, size_t len,
173 size_t *retlen, uint8_t *buf)
174{
175 struct mtd_oob_ops ops;
176 int res;
177
178 ops.mode = MTD_OOB_PLACE;
179 ops.ooboffs = offs & (mtd->writesize - 1);
180 ops.ooblen = len;
181 ops.oobbuf = buf;
182 ops.datbuf = NULL;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200183
184 res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops);
Vitaly Wool70145682006-11-03 18:20:38 +0300185 *retlen = ops.oobretlen;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200186 return res;
187}
188
189/*
190 * Write data and oob to flash
191 */
192static int inftl_write(struct mtd_info *mtd, loff_t offs, size_t len,
193 size_t *retlen, uint8_t *buf, uint8_t *oob)
194{
195 struct mtd_oob_ops ops;
196 int res;
197
198 ops.mode = MTD_OOB_PLACE;
199 ops.ooboffs = offs;
200 ops.ooblen = mtd->oobsize;
201 ops.oobbuf = oob;
202 ops.datbuf = buf;
203 ops.len = len;
204
205 res = mtd->write_oob(mtd, offs & ~(mtd->writesize - 1), &ops);
206 *retlen = ops.retlen;
207 return res;
208}
209
210/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 * INFTL_findfreeblock: Find a free Erase Unit on the INFTL partition.
212 * This function is used when the give Virtual Unit Chain.
213 */
214static u16 INFTL_findfreeblock(struct INFTLrecord *inftl, int desperate)
215{
216 u16 pot = inftl->LastFreeEUN;
217 int silly = inftl->nb_blocks;
218
219 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_findfreeblock(inftl=%p,"
220 "desperate=%d)\n", inftl, desperate);
221
222 /*
223 * Normally, we force a fold to happen before we run out of free
224 * blocks completely.
225 */
226 if (!desperate && inftl->numfreeEUNs < 2) {
227 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: there are too few free "
228 "EUNs (%d)\n", inftl->numfreeEUNs);
229 return 0xffff;
230 }
231
232 /* Scan for a free block */
233 do {
234 if (inftl->PUtable[pot] == BLOCK_FREE) {
235 inftl->LastFreeEUN = pot;
236 return pot;
237 }
238
239 if (++pot > inftl->lastEUN)
240 pot = 0;
241
242 if (!silly--) {
243 printk(KERN_WARNING "INFTL: no free blocks found! "
244 "EUN range = %d - %d\n", 0, inftl->LastFreeEUN);
245 return BLOCK_NIL;
246 }
247 } while (pot != inftl->LastFreeEUN);
248
249 return BLOCK_NIL;
250}
251
252static u16 INFTL_foldchain(struct INFTLrecord *inftl, unsigned thisVUC, unsigned pendingblock)
253{
254 u16 BlockMap[MAX_SECTORS_PER_UNIT];
255 unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT];
256 unsigned int thisEUN, prevEUN, status;
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200257 struct mtd_info *mtd = inftl->mbd.mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 int block, silly;
259 unsigned int targetEUN;
260 struct inftl_oob oob;
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200261 size_t retlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262
263 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_foldchain(inftl=%p,thisVUC=%d,"
264 "pending=%d)\n", inftl, thisVUC, pendingblock);
265
266 memset(BlockMap, 0xff, sizeof(BlockMap));
267 memset(BlockDeleted, 0, sizeof(BlockDeleted));
268
269 thisEUN = targetEUN = inftl->VUtable[thisVUC];
270
271 if (thisEUN == BLOCK_NIL) {
272 printk(KERN_WARNING "INFTL: trying to fold non-existent "
273 "Virtual Unit Chain %d!\n", thisVUC);
274 return BLOCK_NIL;
275 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000276
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 /*
278 * Scan to find the Erase Unit which holds the actual data for each
279 * 512-byte block within the Chain.
280 */
Thomas Gleixner9223a452006-05-23 17:21:03 +0200281 silly = MAX_LOOPS;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 while (thisEUN < inftl->nb_blocks) {
283 for (block = 0; block < inftl->EraseSize/SECTORSIZE; block ++) {
284 if ((BlockMap[block] != 0xffff) || BlockDeleted[block])
285 continue;
286
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200287 if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize)
288 + (block * SECTORSIZE), 16, &retlen,
289 (char *)&oob) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 status = SECTOR_IGNORE;
291 else
Thomas Gleixner9223a452006-05-23 17:21:03 +0200292 status = oob.b.Status | oob.b.Status1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
294 switch(status) {
295 case SECTOR_FREE:
296 case SECTOR_IGNORE:
297 break;
298 case SECTOR_USED:
299 BlockMap[block] = thisEUN;
300 continue;
301 case SECTOR_DELETED:
302 BlockDeleted[block] = 1;
303 continue;
304 default:
305 printk(KERN_WARNING "INFTL: unknown status "
306 "for block %d in EUN %d: %x\n",
307 block, thisEUN, status);
308 break;
309 }
310 }
311
312 if (!silly--) {
313 printk(KERN_WARNING "INFTL: infinite loop in Virtual "
314 "Unit Chain 0x%x\n", thisVUC);
315 return BLOCK_NIL;
316 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000317
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318 thisEUN = inftl->PUtable[thisEUN];
319 }
320
321 /*
322 * OK. We now know the location of every block in the Virtual Unit
323 * Chain, and the Erase Unit into which we are supposed to be copying.
324 * Go for it.
325 */
326 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: folding chain %d into unit %d\n",
327 thisVUC, targetEUN);
328
329 for (block = 0; block < inftl->EraseSize/SECTORSIZE ; block++) {
330 unsigned char movebuf[SECTORSIZE];
331 int ret;
332
333 /*
334 * If it's in the target EUN already, or if it's pending write,
335 * do nothing.
336 */
337 if (BlockMap[block] == targetEUN || (pendingblock ==
338 (thisVUC * (inftl->EraseSize / SECTORSIZE) + block))) {
339 continue;
340 }
341
Thomas Gleixner9223a452006-05-23 17:21:03 +0200342 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700343 * Copy only in non free block (free blocks can only
344 * happen in case of media errors or deleted blocks).
345 */
Thomas Gleixner9223a452006-05-23 17:21:03 +0200346 if (BlockMap[block] == BLOCK_NIL)
347 continue;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000348
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200349 ret = mtd->read(mtd, (inftl->EraseSize * BlockMap[block]) +
350 (block * SECTORSIZE), SECTORSIZE, &retlen,
351 movebuf);
Thomas Gleixner9a1fcdf2006-05-29 14:56:39 +0200352 if (ret < 0 && ret != -EUCLEAN) {
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200353 ret = mtd->read(mtd,
354 (inftl->EraseSize * BlockMap[block]) +
355 (block * SECTORSIZE), SECTORSIZE,
356 &retlen, movebuf);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000357 if (ret != -EIO)
Thomas Gleixner9223a452006-05-23 17:21:03 +0200358 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: error went "
359 "away on retry?\n");
360 }
361 memset(&oob, 0xff, sizeof(struct inftl_oob));
362 oob.b.Status = oob.b.Status1 = SECTOR_USED;
363
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200364 inftl_write(inftl->mbd.mtd, (inftl->EraseSize * targetEUN) +
365 (block * SECTORSIZE), SECTORSIZE, &retlen,
366 movebuf, (char *)&oob);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 }
368
369 /*
370 * Newest unit in chain now contains data from _all_ older units.
371 * So go through and erase each unit in chain, oldest first. (This
372 * is important, by doing oldest first if we crash/reboot then it
373 * it is relatively simple to clean up the mess).
374 */
375 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: want to erase virtual chain %d\n",
376 thisVUC);
377
378 for (;;) {
379 /* Find oldest unit in chain. */
380 thisEUN = inftl->VUtable[thisVUC];
381 prevEUN = BLOCK_NIL;
382 while (inftl->PUtable[thisEUN] != BLOCK_NIL) {
383 prevEUN = thisEUN;
384 thisEUN = inftl->PUtable[thisEUN];
385 }
386
387 /* Check if we are all done */
388 if (thisEUN == targetEUN)
389 break;
390
Daniel Rosenthal63fd7f32008-10-05 17:43:10 -0400391 /* Unlink the last block from the chain. */
392 inftl->PUtable[prevEUN] = BLOCK_NIL;
393
394 /* Now try to erase it. */
Thomas Gleixner9223a452006-05-23 17:21:03 +0200395 if (INFTL_formatblock(inftl, thisEUN) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 /*
397 * Could not erase : mark block as reserved.
398 */
399 inftl->PUtable[thisEUN] = BLOCK_RESERVED;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200400 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 /* Correctly erased : mark it as free */
402 inftl->PUtable[thisEUN] = BLOCK_FREE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 inftl->numfreeEUNs++;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200404 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 }
406
407 return targetEUN;
408}
409
410static u16 INFTL_makefreeblock(struct INFTLrecord *inftl, unsigned pendingblock)
411{
412 /*
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000413 * This is the part that needs some cleverness applied.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 * For now, I'm doing the minimum applicable to actually
415 * get the thing to work.
416 * Wear-levelling and other clever stuff needs to be implemented
417 * and we also need to do some assessment of the results when
418 * the system loses power half-way through the routine.
419 */
420 u16 LongestChain = 0;
421 u16 ChainLength = 0, thislen;
422 u16 chain, EUN;
423
424 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_makefreeblock(inftl=%p,"
425 "pending=%d)\n", inftl, pendingblock);
426
427 for (chain = 0; chain < inftl->nb_blocks; chain++) {
428 EUN = inftl->VUtable[chain];
429 thislen = 0;
430
431 while (EUN <= inftl->lastEUN) {
432 thislen++;
433 EUN = inftl->PUtable[EUN];
434 if (thislen > 0xff00) {
435 printk(KERN_WARNING "INFTL: endless loop in "
436 "Virtual Chain %d: Unit %x\n",
437 chain, EUN);
438 /*
439 * Actually, don't return failure.
440 * Just ignore this chain and get on with it.
441 */
442 thislen = 0;
443 break;
444 }
445 }
446
447 if (thislen > ChainLength) {
448 ChainLength = thislen;
449 LongestChain = chain;
450 }
451 }
452
453 if (ChainLength < 2) {
454 printk(KERN_WARNING "INFTL: no Virtual Unit Chains available "
455 "for folding. Failing request\n");
456 return BLOCK_NIL;
457 }
458
459 return INFTL_foldchain(inftl, LongestChain, pendingblock);
460}
461
462static int nrbits(unsigned int val, int bitcount)
463{
464 int i, total = 0;
465
466 for (i = 0; (i < bitcount); i++)
467 total += (((0x1 << i) & val) ? 1 : 0);
468 return total;
469}
470
471/*
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000472 * INFTL_findwriteunit: Return the unit number into which we can write
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 * for this block. Make it available if it isn't already.
474 */
475static inline u16 INFTL_findwriteunit(struct INFTLrecord *inftl, unsigned block)
476{
477 unsigned int thisVUC = block / (inftl->EraseSize / SECTORSIZE);
478 unsigned int thisEUN, writeEUN, prev_block, status;
479 unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize -1);
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200480 struct mtd_info *mtd = inftl->mbd.mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 struct inftl_oob oob;
482 struct inftl_bci bci;
483 unsigned char anac, nacs, parity;
484 size_t retlen;
485 int silly, silly2 = 3;
486
487 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_findwriteunit(inftl=%p,"
488 "block=%d)\n", inftl, block);
489
490 do {
491 /*
492 * Scan the media to find a unit in the VUC which has
493 * a free space for the block in question.
494 */
495 writeEUN = BLOCK_NIL;
496 thisEUN = inftl->VUtable[thisVUC];
497 silly = MAX_LOOPS;
498
499 while (thisEUN <= inftl->lastEUN) {
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200500 inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) +
501 blockofs, 8, &retlen, (char *)&bci);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502
Thomas Gleixner9223a452006-05-23 17:21:03 +0200503 status = bci.Status | bci.Status1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: status of block %d in "
505 "EUN %d is %x\n", block , writeEUN, status);
506
507 switch(status) {
508 case SECTOR_FREE:
509 writeEUN = thisEUN;
510 break;
511 case SECTOR_DELETED:
512 case SECTOR_USED:
513 /* Can't go any further */
514 goto hitused;
515 case SECTOR_IGNORE:
516 break;
517 default:
518 /*
519 * Invalid block. Don't use it any more.
520 * Must implement.
521 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000522 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000524
525 if (!silly--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 printk(KERN_WARNING "INFTL: infinite loop in "
527 "Virtual Unit Chain 0x%x\n", thisVUC);
528 return 0xffff;
529 }
530
531 /* Skip to next block in chain */
532 thisEUN = inftl->PUtable[thisEUN];
533 }
534
535hitused:
536 if (writeEUN != BLOCK_NIL)
537 return writeEUN;
538
539
540 /*
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000541 * OK. We didn't find one in the existing chain, or there
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 * is no existing chain. Allocate a new one.
543 */
544 writeEUN = INFTL_findfreeblock(inftl, 0);
545
546 if (writeEUN == BLOCK_NIL) {
547 /*
548 * That didn't work - there were no free blocks just
549 * waiting to be picked up. We're going to have to fold
550 * a chain to make room.
551 */
552 thisEUN = INFTL_makefreeblock(inftl, 0xffff);
553
554 /*
555 * Hopefully we free something, lets try again.
556 * This time we are desperate...
557 */
558 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: using desperate==1 "
559 "to find free EUN to accommodate write to "
560 "VUC %d\n", thisVUC);
561 writeEUN = INFTL_findfreeblock(inftl, 1);
562 if (writeEUN == BLOCK_NIL) {
563 /*
564 * Ouch. This should never happen - we should
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000565 * always be able to make some room somehow.
566 * If we get here, we've allocated more storage
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 * space than actual media, or our makefreeblock
568 * routine is missing something.
569 */
570 printk(KERN_WARNING "INFTL: cannot make free "
571 "space.\n");
572#ifdef DEBUG
573 INFTL_dumptables(inftl);
574 INFTL_dumpVUchains(inftl);
575#endif
576 return BLOCK_NIL;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000577 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 }
579
580 /*
581 * Insert new block into virtual chain. Firstly update the
582 * block headers in flash...
583 */
584 anac = 0;
585 nacs = 0;
586 thisEUN = inftl->VUtable[thisVUC];
587 if (thisEUN != BLOCK_NIL) {
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200588 inftl_read_oob(mtd, thisEUN * inftl->EraseSize
589 + 8, 8, &retlen, (char *)&oob.u);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 anac = oob.u.a.ANAC + 1;
591 nacs = oob.u.a.NACs + 1;
592 }
593
594 prev_block = inftl->VUtable[thisVUC];
595 if (prev_block < inftl->nb_blocks)
596 prev_block -= inftl->firstEUN;
597
598 parity = (nrbits(thisVUC, 16) & 0x1) ? 0x1 : 0;
599 parity |= (nrbits(prev_block, 16) & 0x1) ? 0x2 : 0;
600 parity |= (nrbits(anac, 8) & 0x1) ? 0x4 : 0;
601 parity |= (nrbits(nacs, 8) & 0x1) ? 0x8 : 0;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000602
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 oob.u.a.virtualUnitNo = cpu_to_le16(thisVUC);
604 oob.u.a.prevUnitNo = cpu_to_le16(prev_block);
605 oob.u.a.ANAC = anac;
606 oob.u.a.NACs = nacs;
607 oob.u.a.parityPerField = parity;
608 oob.u.a.discarded = 0xaa;
609
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200610 inftl_write_oob(mtd, writeEUN * inftl->EraseSize + 8, 8,
611 &retlen, (char *)&oob.u);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612
613 /* Also back up header... */
614 oob.u.b.virtualUnitNo = cpu_to_le16(thisVUC);
615 oob.u.b.prevUnitNo = cpu_to_le16(prev_block);
616 oob.u.b.ANAC = anac;
617 oob.u.b.NACs = nacs;
618 oob.u.b.parityPerField = parity;
619 oob.u.b.discarded = 0xaa;
620
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200621 inftl_write_oob(mtd, writeEUN * inftl->EraseSize +
622 SECTORSIZE * 4 + 8, 8, &retlen, (char *)&oob.u);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623
624 inftl->PUtable[writeEUN] = inftl->VUtable[thisVUC];
625 inftl->VUtable[thisVUC] = writeEUN;
626
627 inftl->numfreeEUNs--;
628 return writeEUN;
629
630 } while (silly2--);
631
632 printk(KERN_WARNING "INFTL: error folding to make room for Virtual "
633 "Unit Chain 0x%x\n", thisVUC);
634 return 0xffff;
635}
636
637/*
638 * Given a Virtual Unit Chain, see if it can be deleted, and if so do it.
639 */
640static void INFTL_trydeletechain(struct INFTLrecord *inftl, unsigned thisVUC)
641{
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200642 struct mtd_info *mtd = inftl->mbd.mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 unsigned char BlockUsed[MAX_SECTORS_PER_UNIT];
644 unsigned char BlockDeleted[MAX_SECTORS_PER_UNIT];
645 unsigned int thisEUN, status;
646 int block, silly;
647 struct inftl_bci bci;
648 size_t retlen;
649
650 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_trydeletechain(inftl=%p,"
651 "thisVUC=%d)\n", inftl, thisVUC);
652
653 memset(BlockUsed, 0, sizeof(BlockUsed));
654 memset(BlockDeleted, 0, sizeof(BlockDeleted));
655
656 thisEUN = inftl->VUtable[thisVUC];
657 if (thisEUN == BLOCK_NIL) {
658 printk(KERN_WARNING "INFTL: trying to delete non-existent "
659 "Virtual Unit Chain %d!\n", thisVUC);
660 return;
661 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000662
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 /*
664 * Scan through the Erase Units to determine whether any data is in
665 * each of the 512-byte blocks within the Chain.
666 */
667 silly = MAX_LOOPS;
668 while (thisEUN < inftl->nb_blocks) {
669 for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++) {
670 if (BlockUsed[block] || BlockDeleted[block])
671 continue;
672
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200673 if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize)
674 + (block * SECTORSIZE), 8 , &retlen,
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200675 (char *)&bci) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 status = SECTOR_IGNORE;
677 else
678 status = bci.Status | bci.Status1;
679
680 switch(status) {
681 case SECTOR_FREE:
682 case SECTOR_IGNORE:
683 break;
684 case SECTOR_USED:
685 BlockUsed[block] = 1;
686 continue;
687 case SECTOR_DELETED:
688 BlockDeleted[block] = 1;
689 continue;
690 default:
691 printk(KERN_WARNING "INFTL: unknown status "
692 "for block %d in EUN %d: 0x%x\n",
693 block, thisEUN, status);
694 }
695 }
696
697 if (!silly--) {
698 printk(KERN_WARNING "INFTL: infinite loop in Virtual "
699 "Unit Chain 0x%x\n", thisVUC);
700 return;
701 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000702
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 thisEUN = inftl->PUtable[thisEUN];
704 }
705
706 for (block = 0; block < inftl->EraseSize/SECTORSIZE; block++)
707 if (BlockUsed[block])
708 return;
709
710 /*
711 * For each block in the chain free it and make it available
712 * for future use. Erase from the oldest unit first.
713 */
714 DEBUG(MTD_DEBUG_LEVEL1, "INFTL: deleting empty VUC %d\n", thisVUC);
715
716 for (;;) {
717 u16 *prevEUN = &inftl->VUtable[thisVUC];
718 thisEUN = *prevEUN;
719
720 /* If the chain is all gone already, we're done */
721 if (thisEUN == BLOCK_NIL) {
722 DEBUG(MTD_DEBUG_LEVEL2, "INFTL: Empty VUC %d for deletion was already absent\n", thisEUN);
723 return;
724 }
725
726 /* Find oldest unit in chain. */
727 while (inftl->PUtable[thisEUN] != BLOCK_NIL) {
728 BUG_ON(thisEUN >= inftl->nb_blocks);
729
730 prevEUN = &inftl->PUtable[thisEUN];
731 thisEUN = *prevEUN;
732 }
733
734 DEBUG(MTD_DEBUG_LEVEL3, "Deleting EUN %d from VUC %d\n",
735 thisEUN, thisVUC);
736
Thomas Gleixner9223a452006-05-23 17:21:03 +0200737 if (INFTL_formatblock(inftl, thisEUN) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 /*
739 * Could not erase : mark block as reserved.
740 */
741 inftl->PUtable[thisEUN] = BLOCK_RESERVED;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200742 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 /* Correctly erased : mark it as free */
744 inftl->PUtable[thisEUN] = BLOCK_FREE;
745 inftl->numfreeEUNs++;
746 }
747
748 /* Now sort out whatever was pointing to it... */
749 *prevEUN = BLOCK_NIL;
750
751 /* Ideally we'd actually be responsive to new
752 requests while we're doing this -- if there's
753 free space why should others be made to wait? */
754 cond_resched();
755 }
756
757 inftl->VUtable[thisVUC] = BLOCK_NIL;
758}
759
760static int INFTL_deleteblock(struct INFTLrecord *inftl, unsigned block)
761{
762 unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)];
763 unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1);
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200764 struct mtd_info *mtd = inftl->mbd.mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 unsigned int status;
766 int silly = MAX_LOOPS;
767 size_t retlen;
768 struct inftl_bci bci;
769
770 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: INFTL_deleteblock(inftl=%p,"
771 "block=%d)\n", inftl, block);
772
773 while (thisEUN < inftl->nb_blocks) {
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200774 if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) +
775 blockofs, 8, &retlen, (char *)&bci) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 status = SECTOR_IGNORE;
777 else
778 status = bci.Status | bci.Status1;
779
780 switch (status) {
781 case SECTOR_FREE:
782 case SECTOR_IGNORE:
783 break;
784 case SECTOR_DELETED:
785 thisEUN = BLOCK_NIL;
786 goto foundit;
787 case SECTOR_USED:
788 goto foundit;
789 default:
790 printk(KERN_WARNING "INFTL: unknown status for "
791 "block %d in EUN %d: 0x%x\n",
792 block, thisEUN, status);
793 break;
794 }
795
796 if (!silly--) {
797 printk(KERN_WARNING "INFTL: infinite loop in Virtual "
798 "Unit Chain 0x%x\n",
799 block / (inftl->EraseSize / SECTORSIZE));
800 return 1;
801 }
802 thisEUN = inftl->PUtable[thisEUN];
803 }
804
805foundit:
806 if (thisEUN != BLOCK_NIL) {
807 loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs;
808
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200809 if (inftl_read_oob(mtd, ptr, 8, &retlen, (char *)&bci) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 return -EIO;
811 bci.Status = bci.Status1 = SECTOR_DELETED;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200812 if (inftl_write_oob(mtd, ptr, 8, &retlen, (char *)&bci) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 return -EIO;
814 INFTL_trydeletechain(inftl, block / (inftl->EraseSize / SECTORSIZE));
815 }
816 return 0;
817}
818
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000819static int inftl_writeblock(struct mtd_blktrans_dev *mbd, unsigned long block,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 char *buffer)
821{
822 struct INFTLrecord *inftl = (void *)mbd;
823 unsigned int writeEUN;
824 unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1);
825 size_t retlen;
826 struct inftl_oob oob;
827 char *p, *pend;
828
829 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: inftl_writeblock(inftl=%p,block=%ld,"
830 "buffer=%p)\n", inftl, block, buffer);
831
832 /* Is block all zero? */
833 pend = buffer + SECTORSIZE;
834 for (p = buffer; p < pend && !*p; p++)
835 ;
836
837 if (p < pend) {
838 writeEUN = INFTL_findwriteunit(inftl, block);
839
840 if (writeEUN == BLOCK_NIL) {
841 printk(KERN_WARNING "inftl_writeblock(): cannot find "
842 "block to write to\n");
843 /*
844 * If we _still_ haven't got a block to use,
845 * we're screwed.
846 */
847 return 1;
848 }
849
850 memset(&oob, 0xff, sizeof(struct inftl_oob));
851 oob.b.Status = oob.b.Status1 = SECTOR_USED;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200852
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200853 inftl_write(inftl->mbd.mtd, (writeEUN * inftl->EraseSize) +
854 blockofs, SECTORSIZE, &retlen, (char *)buffer,
855 (char *)&oob);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700856 /*
857 * need to write SECTOR_USED flags since they are not written
858 * in mtd_writeecc
859 */
860 } else {
861 INFTL_deleteblock(inftl, block);
862 }
863
864 return 0;
865}
866
867static int inftl_readblock(struct mtd_blktrans_dev *mbd, unsigned long block,
868 char *buffer)
869{
870 struct INFTLrecord *inftl = (void *)mbd;
871 unsigned int thisEUN = inftl->VUtable[block / (inftl->EraseSize / SECTORSIZE)];
872 unsigned long blockofs = (block * SECTORSIZE) & (inftl->EraseSize - 1);
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200873 struct mtd_info *mtd = inftl->mbd.mtd;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200874 unsigned int status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 int silly = MAX_LOOPS;
Thomas Gleixner9223a452006-05-23 17:21:03 +0200876 struct inftl_bci bci;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 size_t retlen;
878
879 DEBUG(MTD_DEBUG_LEVEL3, "INFTL: inftl_readblock(inftl=%p,block=%ld,"
880 "buffer=%p)\n", inftl, block, buffer);
881
882 while (thisEUN < inftl->nb_blocks) {
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200883 if (inftl_read_oob(mtd, (thisEUN * inftl->EraseSize) +
Thomas Gleixnerf4a43cf2006-05-28 11:01:53 +0200884 blockofs, 8, &retlen, (char *)&bci) < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 status = SECTOR_IGNORE;
886 else
887 status = bci.Status | bci.Status1;
888
889 switch (status) {
890 case SECTOR_DELETED:
891 thisEUN = BLOCK_NIL;
892 goto foundit;
893 case SECTOR_USED:
894 goto foundit;
895 case SECTOR_FREE:
896 case SECTOR_IGNORE:
897 break;
898 default:
899 printk(KERN_WARNING "INFTL: unknown status for "
900 "block %ld in EUN %d: 0x%04x\n",
901 block, thisEUN, status);
902 break;
903 }
904
905 if (!silly--) {
906 printk(KERN_WARNING "INFTL: infinite loop in "
907 "Virtual Unit Chain 0x%lx\n",
908 block / (inftl->EraseSize / SECTORSIZE));
909 return 1;
910 }
911
912 thisEUN = inftl->PUtable[thisEUN];
913 }
914
915foundit:
916 if (thisEUN == BLOCK_NIL) {
917 /* The requested block is not on the media, return all 0x00 */
918 memset(buffer, 0, SECTORSIZE);
919 } else {
Thomas Gleixner9223a452006-05-23 17:21:03 +0200920 size_t retlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 loff_t ptr = (thisEUN * inftl->EraseSize) + blockofs;
Thomas Gleixner9a1fcdf2006-05-29 14:56:39 +0200922 int ret = mtd->read(mtd, ptr, SECTORSIZE, &retlen, buffer);
923
924 /* Handle corrected bit flips gracefully */
925 if (ret < 0 && ret != -EUCLEAN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 return -EIO;
927 }
928 return 0;
929}
930
931static int inftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
932{
933 struct INFTLrecord *inftl = (void *)dev;
934
935 geo->heads = inftl->heads;
936 geo->sectors = inftl->sectors;
937 geo->cylinders = inftl->cylinders;
938
939 return 0;
940}
941
942static struct mtd_blktrans_ops inftl_tr = {
943 .name = "inftl",
944 .major = INFTL_MAJOR,
945 .part_bits = INFTL_PARTN_BITS,
Richard Purdie19187672006-10-27 09:09:33 +0100946 .blksize = 512,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 .getgeo = inftl_getgeo,
948 .readsect = inftl_readblock,
949 .writesect = inftl_writeblock,
950 .add_mtd = inftl_add_mtd,
951 .remove_dev = inftl_remove_dev,
952 .owner = THIS_MODULE,
953};
954
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955static int __init init_inftl(void)
956{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700957 return register_mtd_blktrans(&inftl_tr);
958}
959
960static void __exit cleanup_inftl(void)
961{
962 deregister_mtd_blktrans(&inftl_tr);
963}
964
965module_init(init_inftl);
966module_exit(cleanup_inftl);
967
968MODULE_LICENSE("GPL");
969MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>, David Woodhouse <dwmw2@infradead.org>, Fabrice Bellard <fabrice.bellard@netgem.com> et al.");
970MODULE_DESCRIPTION("Support code for Inverse Flash Translation Layer, used on M-Systems DiskOnChip 2000, Millennium and Millennium Plus");