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1/*
2 * Copyright © 2009 - Maxim Levitsky
3 * SmartMedia/xD translation layer
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/random.h>
13#include <linux/hdreg.h>
14#include <linux/kthread.h>
15#include <linux/freezer.h>
16#include <linux/sysfs.h>
17#include <linux/bitops.h>
18#include <linux/slab.h>
19#include <linux/mtd/nand_ecc.h>
20#include "nand/sm_common.h"
21#include "sm_ftl.h"
22
23
24
25struct workqueue_struct *cache_flush_workqueue;
26
27static int cache_timeout = 1000;
28module_param(cache_timeout, bool, S_IRUGO);
29MODULE_PARM_DESC(cache_timeout,
30 "Timeout (in ms) for cache flush (1000 ms default");
31
32static int debug;
33module_param(debug, int, S_IRUGO | S_IWUSR);
34MODULE_PARM_DESC(debug, "Debug level (0-2)");
35
36
37/* ------------------- sysfs attributtes ---------------------------------- */
38struct sm_sysfs_attribute {
39 struct device_attribute dev_attr;
40 char *data;
41 int len;
42};
43
44ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr,
45 char *buf)
46{
47 struct sm_sysfs_attribute *sm_attr =
48 container_of(attr, struct sm_sysfs_attribute, dev_attr);
49
50 strncpy(buf, sm_attr->data, sm_attr->len);
51 return sm_attr->len;
52}
53
54
55#define NUM_ATTRIBUTES 1
56#define SM_CIS_VENDOR_OFFSET 0x59
57struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl)
58{
59 struct attribute_group *attr_group;
60 struct attribute **attributes;
61 struct sm_sysfs_attribute *vendor_attribute;
62
63 int vendor_len = strnlen(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET,
64 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET);
65
66 char *vendor = kmalloc(vendor_len, GFP_KERNEL);
67 if (!vendor)
68 goto error1;
69 memcpy(vendor, ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, vendor_len);
70 vendor[vendor_len] = 0;
71
72 /* Initialize sysfs attributes */
73 vendor_attribute =
74 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL);
75 if (!vendor_attribute)
76 goto error2;
77
78 sysfs_attr_init(&vendor_attribute->dev_attr.attr);
79
80 vendor_attribute->data = vendor;
81 vendor_attribute->len = vendor_len;
82 vendor_attribute->dev_attr.attr.name = "vendor";
83 vendor_attribute->dev_attr.attr.mode = S_IRUGO;
84 vendor_attribute->dev_attr.show = sm_attr_show;
85
86
87 /* Create array of pointers to the attributes */
88 attributes = kzalloc(sizeof(struct attribute *) * (NUM_ATTRIBUTES + 1),
89 GFP_KERNEL);
90 if (!attributes)
91 goto error3;
92 attributes[0] = &vendor_attribute->dev_attr.attr;
93
94 /* Finally create the attribute group */
95 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
96 if (!attr_group)
97 goto error4;
98 attr_group->attrs = attributes;
99 return attr_group;
100error4:
101 kfree(attributes);
102error3:
103 kfree(vendor_attribute);
104error2:
105 kfree(vendor);
106error1:
107 return NULL;
108}
109
110void sm_delete_sysfs_attributes(struct sm_ftl *ftl)
111{
112 struct attribute **attributes = ftl->disk_attributes->attrs;
113 int i;
114
115 for (i = 0; attributes[i] ; i++) {
116
117 struct device_attribute *dev_attr = container_of(attributes[i],
118 struct device_attribute, attr);
119
120 struct sm_sysfs_attribute *sm_attr =
121 container_of(dev_attr,
122 struct sm_sysfs_attribute, dev_attr);
123
124 kfree(sm_attr->data);
125 kfree(sm_attr);
126 }
127
128 kfree(ftl->disk_attributes->attrs);
129 kfree(ftl->disk_attributes);
130}
131
132
133/* ----------------------- oob helpers -------------------------------------- */
134
135static int sm_get_lba(uint8_t *lba)
136{
137 /* check fixed bits */
138 if ((lba[0] & 0xF8) != 0x10)
139 return -2;
140
141 /* check parity - endianess doesn't matter */
142 if (hweight16(*(uint16_t *)lba) & 1)
143 return -2;
144
145 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7);
146}
147
148
149/*
150 * Read LBA asscociated with block
151 * returns -1, if block is erased
152 * returns -2 if error happens
153 */
154static int sm_read_lba(struct sm_oob *oob)
155{
156 static const uint32_t erased_pattern[4] = {
157 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
158
159 uint16_t lba_test;
160 int lba;
161
162 /* First test for erased block */
163 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE))
164 return -1;
165
166 /* Now check is both copies of the LBA differ too much */
167 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2;
168 if (lba_test && !is_power_of_2(lba_test))
169 return -2;
170
171 /* And read it */
172 lba = sm_get_lba(oob->lba_copy1);
173
174 if (lba == -2)
175 lba = sm_get_lba(oob->lba_copy2);
176
177 return lba;
178}
179
180static void sm_write_lba(struct sm_oob *oob, uint16_t lba)
181{
182 uint8_t tmp[2];
183
184 WARN_ON(lba >= 1000);
185
186 tmp[0] = 0x10 | ((lba >> 7) & 0x07);
187 tmp[1] = (lba << 1) & 0xFF;
188
189 if (hweight16(*(uint16_t *)tmp) & 0x01)
190 tmp[1] |= 1;
191
192 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0];
193 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1];
194}
195
196
197/* Make offset from parts */
198static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset)
199{
200 WARN_ON(boffset & (SM_SECTOR_SIZE - 1));
201 WARN_ON(zone < 0 || zone >= ftl->zone_count);
202 WARN_ON(block >= ftl->zone_size);
203 WARN_ON(boffset >= ftl->block_size);
204
205 if (block == -1)
206 return -1;
207
208 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset;
209}
210
211/* Breaks offset into parts */
212static void sm_break_offset(struct sm_ftl *ftl, loff_t offset,
213 int *zone, int *block, int *boffset)
214{
215 *boffset = do_div(offset, ftl->block_size);
216 *block = do_div(offset, ftl->max_lba);
217 *zone = offset >= ftl->zone_count ? -1 : offset;
218}
219
220/* ---------------------- low level IO ------------------------------------- */
221
222static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob)
223{
224 uint8_t ecc[3];
225
226 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
227 if (__nand_correct_data(buffer, ecc, oob->ecc1, SM_SMALL_PAGE) < 0)
228 return -EIO;
229
230 buffer += SM_SMALL_PAGE;
231
232 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
233 if (__nand_correct_data(buffer, ecc, oob->ecc2, SM_SMALL_PAGE) < 0)
234 return -EIO;
235 return 0;
236}
237
238/* Reads a sector + oob*/
239static int sm_read_sector(struct sm_ftl *ftl,
240 int zone, int block, int boffset,
241 uint8_t *buffer, struct sm_oob *oob)
242{
243 struct mtd_info *mtd = ftl->trans->mtd;
244 struct mtd_oob_ops ops;
245 struct sm_oob tmp_oob;
246 int ret = -EIO;
247 int try = 0;
248
249 /* FTL can contain -1 entries that are by default filled with bits */
250 if (block == -1) {
251 memset(buffer, 0xFF, SM_SECTOR_SIZE);
252 return 0;
253 }
254
255 /* User might not need the oob, but we do for data vertification */
256 if (!oob)
257 oob = &tmp_oob;
258
259 ops.mode = ftl->smallpagenand ? MTD_OOB_RAW : MTD_OOB_PLACE;
260 ops.ooboffs = 0;
261 ops.ooblen = SM_OOB_SIZE;
262 ops.oobbuf = (void *)oob;
263 ops.len = SM_SECTOR_SIZE;
264 ops.datbuf = buffer;
265
266again:
267 if (try++) {
268 /* Avoid infinite recursion on CIS reads, sm_recheck_media
269 won't help anyway */
270 if (zone == 0 && block == ftl->cis_block && boffset ==
271 ftl->cis_boffset)
272 return ret;
273
274 /* Test if media is stable */
275 if (try == 3 || sm_recheck_media(ftl))
276 return ret;
277 }
278
279 /* Unfortunelly, oob read will _always_ succeed,
280 despite card removal..... */
281 ret = mtd->read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
282
283 /* Test for unknown errors */
284 if (ret != 0 && ret != -EUCLEAN && ret != -EBADMSG) {
285 dbg("read of block %d at zone %d, failed due to error (%d)",
286 block, zone, ret);
287 goto again;
288 }
289
290 /* Do a basic test on the oob, to guard against returned garbage */
291 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))
292 goto again;
293
294 /* This should never happen, unless there is a bug in the mtd driver */
295 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
296 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
297
298 if (!buffer)
299 return 0;
300
301 /* Test if sector marked as bad */
302 if (!sm_sector_valid(oob)) {
303 dbg("read of block %d at zone %d, failed because it is marked"
304 " as bad" , block, zone);
305 goto again;
306 }
307
308 /* Test ECC*/
309 if (ret == -EBADMSG ||
310 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {
311
312 dbg("read of block %d at zone %d, failed due to ECC error",
313 block, zone);
314 goto again;
315 }
316
317 return 0;
318}
319
320/* Writes a sector to media */
321static int sm_write_sector(struct sm_ftl *ftl,
322 int zone, int block, int boffset,
323 uint8_t *buffer, struct sm_oob *oob)
324{
325 struct mtd_oob_ops ops;
326 struct mtd_info *mtd = ftl->trans->mtd;
327 int ret;
328
329 BUG_ON(ftl->readonly);
330
331 if (zone == 0 && (block == ftl->cis_block || block == 0)) {
332 dbg("attempted to write the CIS!");
333 return -EIO;
334 }
335
336 if (ftl->unstable)
337 return -EIO;
338
339 ops.mode = ftl->smallpagenand ? MTD_OOB_RAW : MTD_OOB_PLACE;
340 ops.len = SM_SECTOR_SIZE;
341 ops.datbuf = buffer;
342 ops.ooboffs = 0;
343 ops.ooblen = SM_OOB_SIZE;
344 ops.oobbuf = (void *)oob;
345
346 ret = mtd->write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
347
348 /* Now we assume that hardware will catch write bitflip errors */
349 /* If you are paranoid, use CONFIG_MTD_NAND_VERIFY_WRITE */
350
351 if (ret) {
352 dbg("write to block %d at zone %d, failed with error %d",
353 block, zone, ret);
354
355 sm_recheck_media(ftl);
356 return ret;
357 }
358
359 /* This should never happen, unless there is a bug in the driver */
360 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
361 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
362
363 return 0;
364}
365
366/* ------------------------ block IO ------------------------------------- */
367
368/* Write a block using data and lba, and invalid sector bitmap */
369static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,
370 int zone, int block, int lba,
371 unsigned long invalid_bitmap)
372{
373 struct sm_oob oob;
374 int boffset;
375 int retry = 0;
376
377 /* Initialize the oob with requested values */
378 memset(&oob, 0xFF, SM_OOB_SIZE);
379 sm_write_lba(&oob, lba);
380restart:
381 if (ftl->unstable)
382 return -EIO;
383
384 for (boffset = 0; boffset < ftl->block_size;
385 boffset += SM_SECTOR_SIZE) {
386
387 oob.data_status = 0xFF;
388
389 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
390
391 sm_printk("sector %d of block at LBA %d of zone %d"
392 " coudn't be read, marking it as invalid",
393 boffset / SM_SECTOR_SIZE, lba, zone);
394
395 oob.data_status = 0;
396 }
397
398 if (ftl->smallpagenand) {
399 __nand_calculate_ecc(buf + boffset,
400 SM_SMALL_PAGE, oob.ecc1);
401
402 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE,
403 SM_SMALL_PAGE, oob.ecc2);
404 }
405 if (!sm_write_sector(ftl, zone, block, boffset,
406 buf + boffset, &oob))
407 continue;
408
409 if (!retry) {
410
411 /* If write fails. try to erase the block */
412 /* This is safe, because we never write in blocks
413 that contain valuable data.
414 This is intended to repair block that are marked
415 as erased, but that isn't fully erased*/
416
417 if (sm_erase_block(ftl, zone, block, 0))
418 return -EIO;
419
420 retry = 1;
421 goto restart;
422 } else {
423 sm_mark_block_bad(ftl, zone, block);
424 return -EIO;
425 }
426 }
427 return 0;
428}
429
430
431/* Mark whole block at offset 'offs' as bad. */
432static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)
433{
434 struct sm_oob oob;
435 int boffset;
436
437 memset(&oob, 0xFF, SM_OOB_SIZE);
438 oob.block_status = 0xF0;
439
440 if (ftl->unstable)
441 return;
442
443 if (sm_recheck_media(ftl))
444 return;
445
446 sm_printk("marking block %d of zone %d as bad", block, zone);
447
448 /* We aren't checking the return value, because we don't care */
449 /* This also fails on fake xD cards, but I guess these won't expose
450 any bad blocks till fail completly */
451 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)
452 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);
453}
454
455/*
456 * Erase a block within a zone
457 * If erase succedes, it updates free block fifo, otherwise marks block as bad
458 */
459static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
460 int put_free)
461{
462 struct ftl_zone *zone = &ftl->zones[zone_num];
463 struct mtd_info *mtd = ftl->trans->mtd;
464 struct erase_info erase;
465
466 erase.mtd = mtd;
467 erase.callback = sm_erase_callback;
468 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
469 erase.len = ftl->block_size;
470 erase.priv = (u_long)ftl;
471
472 if (ftl->unstable)
473 return -EIO;
474
475 BUG_ON(ftl->readonly);
476
477 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {
478 sm_printk("attempted to erase the CIS!");
479 return -EIO;
480 }
481
482 if (mtd->erase(mtd, &erase)) {
483 sm_printk("erase of block %d in zone %d failed",
484 block, zone_num);
485 goto error;
486 }
487
488 if (erase.state == MTD_ERASE_PENDING)
489 wait_for_completion(&ftl->erase_completion);
490
491 if (erase.state != MTD_ERASE_DONE) {
492 sm_printk("erase of block %d in zone %d failed after wait",
493 block, zone_num);
494 goto error;
495 }
496
497 if (put_free)
498 kfifo_in(&zone->free_sectors,
499 (const unsigned char *)&block, sizeof(block));
500
501 return 0;
502error:
503 sm_mark_block_bad(ftl, zone_num, block);
504 return -EIO;
505}
506
507static void sm_erase_callback(struct erase_info *self)
508{
509 struct sm_ftl *ftl = (struct sm_ftl *)self->priv;
510 complete(&ftl->erase_completion);
511}
512
513/* Throughtly test that block is valid. */
514static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
515{
516 int boffset;
517 struct sm_oob oob;
518 int lbas[] = { -3, 0, 0, 0 };
519 int i = 0;
520 int test_lba;
521
522
523 /* First just check that block doesn't look fishy */
524 /* Only blocks that are valid or are sliced in two parts, are
525 accepted */
526 for (boffset = 0; boffset < ftl->block_size;
527 boffset += SM_SECTOR_SIZE) {
528
529 /* This shoudn't happen anyway */
530 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
531 return -2;
532
533 test_lba = sm_read_lba(&oob);
534
535 if (lbas[i] != test_lba)
536 lbas[++i] = test_lba;
537
538 /* If we found three different LBAs, something is fishy */
539 if (i == 3)
540 return -EIO;
541 }
542
543 /* If the block is sliced (partially erased usually) erase it */
544 if (i == 2) {
545 sm_erase_block(ftl, zone, block, 1);
546 return 1;
547 }
548
549 return 0;
550}
551
552/* ----------------- media scanning --------------------------------- */
553static const struct chs_entry chs_table[] = {
554 { 1, 125, 4, 4 },
555 { 2, 125, 4, 8 },
556 { 4, 250, 4, 8 },
557 { 8, 250, 4, 16 },
558 { 16, 500, 4, 16 },
559 { 32, 500, 8, 16 },
560 { 64, 500, 8, 32 },
561 { 128, 500, 16, 32 },
562 { 256, 1000, 16, 32 },
563 { 512, 1015, 32, 63 },
564 { 1024, 985, 33, 63 },
565 { 2048, 985, 33, 63 },
566 { 0 },
567};
568
569
570static const uint8_t cis_signature[] = {
571 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
572};
573/* Find out media parameters.
574 * This ideally has to be based on nand id, but for now device size is enough */
575int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
576{
577 int i;
578 int size_in_megs = mtd->size / (1024 * 1024);
579
580 ftl->readonly = mtd->type == MTD_ROM;
581
582 /* Manual settings for very old devices */
583 ftl->zone_count = 1;
584 ftl->smallpagenand = 0;
585
586 switch (size_in_megs) {
587 case 1:
588 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
589 ftl->zone_size = 256;
590 ftl->max_lba = 250;
591 ftl->block_size = 8 * SM_SECTOR_SIZE;
592 ftl->smallpagenand = 1;
593
594 break;
595 case 2:
596 /* 2 MiB flash SmartMedia (256 byte pages)*/
597 if (mtd->writesize == SM_SMALL_PAGE) {
598 ftl->zone_size = 512;
599 ftl->max_lba = 500;
600 ftl->block_size = 8 * SM_SECTOR_SIZE;
601 ftl->smallpagenand = 1;
602 /* 2 MiB rom SmartMedia */
603 } else {
604
605 if (!ftl->readonly)
606 return -ENODEV;
607
608 ftl->zone_size = 256;
609 ftl->max_lba = 250;
610 ftl->block_size = 16 * SM_SECTOR_SIZE;
611 }
612 break;
613 case 4:
614 /* 4 MiB flash/rom SmartMedia device */
615 ftl->zone_size = 512;
616 ftl->max_lba = 500;
617 ftl->block_size = 16 * SM_SECTOR_SIZE;
618 break;
619 case 8:
620 /* 8 MiB flash/rom SmartMedia device */
621 ftl->zone_size = 1024;
622 ftl->max_lba = 1000;
623 ftl->block_size = 16 * SM_SECTOR_SIZE;
624 }
625
626 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
627 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/
628 if (size_in_megs >= 16) {
629 ftl->zone_count = size_in_megs / 16;
630 ftl->zone_size = 1024;
631 ftl->max_lba = 1000;
632 ftl->block_size = 32 * SM_SECTOR_SIZE;
633 }
634
635 /* Test for proper write,erase and oob sizes */
636 if (mtd->erasesize > ftl->block_size)
637 return -ENODEV;
638
639 if (mtd->writesize > SM_SECTOR_SIZE)
640 return -ENODEV;
641
642 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
643 return -ENODEV;
644
645 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
646 return -ENODEV;
647
648 /* We use these functions for IO */
649 if (!mtd->read_oob || !mtd->write_oob)
650 return -ENODEV;
651
652 /* Find geometry information */
653 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
654 if (chs_table[i].size == size_in_megs) {
655 ftl->cylinders = chs_table[i].cyl;
656 ftl->heads = chs_table[i].head;
657 ftl->sectors = chs_table[i].sec;
658 return 0;
659 }
660 }
661
662 sm_printk("media has unknown size : %dMiB", size_in_megs);
663 ftl->cylinders = 985;
664 ftl->heads = 33;
665 ftl->sectors = 63;
666 return 0;
667}
668
669/* Validate the CIS */
670static int sm_read_cis(struct sm_ftl *ftl)
671{
672 struct sm_oob oob;
673
674 if (sm_read_sector(ftl,
675 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
676 return -EIO;
677
678 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
679 return -EIO;
680
681 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
682 cis_signature, sizeof(cis_signature))) {
683 return 0;
684 }
685
686 return -EIO;
687}
688
689/* Scan the media for the CIS */
690static int sm_find_cis(struct sm_ftl *ftl)
691{
692 struct sm_oob oob;
693 int block, boffset;
694 int block_found = 0;
695 int cis_found = 0;
696
697 /* Search for first valid block */
698 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
699
700 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
701 continue;
702
703 if (!sm_block_valid(&oob))
704 continue;
705 block_found = 1;
706 break;
707 }
708
709 if (!block_found)
710 return -EIO;
711
712 /* Search for first valid sector in this block */
713 for (boffset = 0 ; boffset < ftl->block_size;
714 boffset += SM_SECTOR_SIZE) {
715
716 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
717 continue;
718
719 if (!sm_sector_valid(&oob))
720 continue;
721 break;
722 }
723
724 if (boffset == ftl->block_size)
725 return -EIO;
726
727 ftl->cis_block = block;
728 ftl->cis_boffset = boffset;
729 ftl->cis_page_offset = 0;
730
731 cis_found = !sm_read_cis(ftl);
732
733 if (!cis_found) {
734 ftl->cis_page_offset = SM_SMALL_PAGE;
735 cis_found = !sm_read_cis(ftl);
736 }
737
738 if (cis_found) {
739 dbg("CIS block found at offset %x",
740 block * ftl->block_size +
741 boffset + ftl->cis_page_offset);
742 return 0;
743 }
744 return -EIO;
745}
746
747/* Basic test to determine if underlying mtd device if functional */
748static int sm_recheck_media(struct sm_ftl *ftl)
749{
750 if (sm_read_cis(ftl)) {
751
752 if (!ftl->unstable) {
753 sm_printk("media unstable, not allowing writes");
754 ftl->unstable = 1;
755 }
756 return -EIO;
757 }
758 return 0;
759}
760
761/* Initialize a FTL zone */
762static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
763{
764 struct ftl_zone *zone = &ftl->zones[zone_num];
765 struct sm_oob oob;
766 uint16_t block;
767 int lba;
768 int i = 0;
769 int len;
770
771 dbg("initializing zone %d", zone_num);
772
773 /* Allocate memory for FTL table */
774 zone->lba_to_phys_table = kmalloc(ftl->max_lba * 2, GFP_KERNEL);
775
776 if (!zone->lba_to_phys_table)
777 return -ENOMEM;
778 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
779
780
781 /* Allocate memory for free sectors FIFO */
782 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
783 kfree(zone->lba_to_phys_table);
784 return -ENOMEM;
785 }
786
787 /* Now scan the zone */
788 for (block = 0 ; block < ftl->zone_size ; block++) {
789
790 /* Skip blocks till the CIS (including) */
791 if (zone_num == 0 && block <= ftl->cis_block)
792 continue;
793
794 /* Read the oob of first sector */
795 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob))
796 return -EIO;
797
798 /* Test to see if block is erased. It is enough to test
799 first sector, because erase happens in one shot */
800 if (sm_block_erased(&oob)) {
801 kfifo_in(&zone->free_sectors,
802 (unsigned char *)&block, 2);
803 continue;
804 }
805
806 /* If block is marked as bad, skip it */
807 /* This assumes we can trust first sector*/
808 /* However the way the block valid status is defined, ensures
809 very low probability of failure here */
810 if (!sm_block_valid(&oob)) {
811 dbg("PH %04d <-> <marked bad>", block);
812 continue;
813 }
814
815
816 lba = sm_read_lba(&oob);
817
818 /* Invalid LBA means that block is damaged. */
819 /* We can try to erase it, or mark it as bad, but
820 lets leave that to recovery application */
821 if (lba == -2 || lba >= ftl->max_lba) {
822 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
823 continue;
824 }
825
826
827 /* If there is no collision,
828 just put the sector in the FTL table */
829 if (zone->lba_to_phys_table[lba] < 0) {
830 dbg_verbose("PH %04d <-> LBA %04d", block, lba);
831 zone->lba_to_phys_table[lba] = block;
832 continue;
833 }
834
835 sm_printk("collision"
836 " of LBA %d between blocks %d and %d in zone %d",
837 lba, zone->lba_to_phys_table[lba], block, zone_num);
838
839 /* Test that this block is valid*/
840 if (sm_check_block(ftl, zone_num, block))
841 continue;
842
843 /* Test now the old block */
844 if (sm_check_block(ftl, zone_num,
845 zone->lba_to_phys_table[lba])) {
846 zone->lba_to_phys_table[lba] = block;
847 continue;
848 }
849
850 /* If both blocks are valid and share same LBA, it means that
851 they hold different versions of same data. It not
852 known which is more recent, thus just erase one of them
853 */
854 sm_printk("both blocks are valid, erasing the later");
855 sm_erase_block(ftl, zone_num, block, 1);
856 }
857
858 dbg("zone initialized");
859 zone->initialized = 1;
860
861 /* No free sectors, means that the zone is heavily damaged, write won't
862 work, but it can still can be (partially) read */
863 if (!kfifo_len(&zone->free_sectors)) {
864 sm_printk("no free blocks in zone %d", zone_num);
865 return 0;
866 }
867
868 /* Randomize first block we write to */
869 get_random_bytes(&i, 2);
870 i %= (kfifo_len(&zone->free_sectors) / 2);
871
872 while (i--) {
873 len = kfifo_out(&zone->free_sectors,
874 (unsigned char *)&block, 2);
875 WARN_ON(len != 2);
876 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
877 }
878 return 0;
879}
880
881/* Get and automatically initialize an FTL mapping for one zone */
882struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
883{
884 struct ftl_zone *zone;
885 int error;
886
887 BUG_ON(zone_num >= ftl->zone_count);
888 zone = &ftl->zones[zone_num];
889
890 if (!zone->initialized) {
891 error = sm_init_zone(ftl, zone_num);
892
893 if (error)
894 return ERR_PTR(error);
895 }
896 return zone;
897}
898
899
900/* ----------------- cache handling ------------------------------------------*/
901
902/* Initialize the one block cache */
903void sm_cache_init(struct sm_ftl *ftl)
904{
905 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
906 ftl->cache_clean = 1;
907 ftl->cache_zone = -1;
908 ftl->cache_block = -1;
909 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
910}
911
912/* Put sector in one block cache */
913void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
914{
915 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
916 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
917 ftl->cache_clean = 0;
918}
919
920/* Read a sector from the cache */
921int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
922{
923 if (test_bit(boffset / SM_SECTOR_SIZE,
924 &ftl->cache_data_invalid_bitmap))
925 return -1;
926
927 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
928 return 0;
929}
930
931/* Write the cache to hardware */
932int sm_cache_flush(struct sm_ftl *ftl)
933{
934 struct ftl_zone *zone;
935
936 int sector_num;
937 uint16_t write_sector;
938 int zone_num = ftl->cache_zone;
939 int block_num;
940
941 if (ftl->cache_clean)
942 return 0;
943
944 if (ftl->unstable)
945 return -EIO;
946
947 BUG_ON(zone_num < 0);
948 zone = &ftl->zones[zone_num];
949 block_num = zone->lba_to_phys_table[ftl->cache_block];
950
951
952 /* Try to read all unread areas of the cache block*/
953 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
954 ftl->block_size / SM_SECTOR_SIZE) {
955
956 if (!sm_read_sector(ftl,
957 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
958 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
959 clear_bit(sector_num,
960 &ftl->cache_data_invalid_bitmap);
961 }
962restart:
963
964 if (ftl->unstable)
965 return -EIO;
966
967 /* If there are no spare blocks, */
968 /* we could still continue by erasing/writing the current block,
969 but for such worn out media it doesn't worth the trouble,
970 and the dangers */
971 if (kfifo_out(&zone->free_sectors,
972 (unsigned char *)&write_sector, 2) != 2) {
973 dbg("no free sectors for write!");
974 return -EIO;
975 }
976
977
978 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
979 ftl->cache_block, ftl->cache_data_invalid_bitmap))
980 goto restart;
981
982 /* Update the FTL table */
983 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
984
985 /* Write succesfull, so erase and free the old block */
986 if (block_num > 0)
987 sm_erase_block(ftl, zone_num, block_num, 1);
988
989 sm_cache_init(ftl);
990 return 0;
991}
992
993
994/* flush timer, runs a second after last write */
995static void sm_cache_flush_timer(unsigned long data)
996{
997 struct sm_ftl *ftl = (struct sm_ftl *)data;
998 queue_work(cache_flush_workqueue, &ftl->flush_work);
999}
1000
1001/* cache flush work, kicked by timer */
1002static void sm_cache_flush_work(struct work_struct *work)
1003{
1004 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
1005 mutex_lock(&ftl->mutex);
1006 sm_cache_flush(ftl);
1007 mutex_unlock(&ftl->mutex);
1008 return;
1009}
1010
1011/* ---------------- outside interface -------------------------------------- */
1012
1013/* outside interface: read a sector */
1014static int sm_read(struct mtd_blktrans_dev *dev,
1015 unsigned long sect_no, char *buf)
1016{
1017 struct sm_ftl *ftl = dev->priv;
1018 struct ftl_zone *zone;
1019 int error = 0, in_cache = 0;
1020 int zone_num, block, boffset;
1021
1022 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1023 mutex_lock(&ftl->mutex);
1024
1025
1026 zone = sm_get_zone(ftl, zone_num);
1027 if (IS_ERR(zone)) {
1028 error = PTR_ERR(zone);
1029 goto unlock;
1030 }
1031
1032 /* Have to look at cache first */
1033 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1034 in_cache = 1;
1035 if (!sm_cache_get(ftl, buf, boffset))
1036 goto unlock;
1037 }
1038
1039 /* Translate the block and return if doesn't exist in the table */
1040 block = zone->lba_to_phys_table[block];
1041
1042 if (block == -1) {
1043 memset(buf, 0xFF, SM_SECTOR_SIZE);
1044 goto unlock;
1045 }
1046
1047 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1048 error = -EIO;
1049 goto unlock;
1050 }
1051
1052 if (in_cache)
1053 sm_cache_put(ftl, buf, boffset);
1054unlock:
1055 mutex_unlock(&ftl->mutex);
1056 return error;
1057}
1058
1059/* outside interface: write a sector */
1060static int sm_write(struct mtd_blktrans_dev *dev,
1061 unsigned long sec_no, char *buf)
1062{
1063 struct sm_ftl *ftl = dev->priv;
1064 struct ftl_zone *zone;
1065 int error, zone_num, block, boffset;
1066
1067 BUG_ON(ftl->readonly);
1068 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1069
1070 /* No need in flush thread running now */
1071 del_timer(&ftl->timer);
1072 mutex_lock(&ftl->mutex);
1073
1074 zone = sm_get_zone(ftl, zone_num);
1075 if (IS_ERR(zone)) {
1076 error = PTR_ERR(zone);
1077 goto unlock;
1078 }
1079
1080 /* If entry is not in cache, flush it */
1081 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1082
1083 error = sm_cache_flush(ftl);
1084 if (error)
1085 goto unlock;
1086
1087 ftl->cache_block = block;
1088 ftl->cache_zone = zone_num;
1089 }
1090
1091 sm_cache_put(ftl, buf, boffset);
1092unlock:
1093 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1094 mutex_unlock(&ftl->mutex);
1095 return error;
1096}
1097
1098/* outside interface: flush everything */
1099static int sm_flush(struct mtd_blktrans_dev *dev)
1100{
1101 struct sm_ftl *ftl = dev->priv;
1102 int retval;
1103
1104 mutex_lock(&ftl->mutex);
1105 retval = sm_cache_flush(ftl);
1106 mutex_unlock(&ftl->mutex);
1107 return retval;
1108}
1109
1110/* outside interface: device is released */
1111static int sm_release(struct mtd_blktrans_dev *dev)
1112{
1113 struct sm_ftl *ftl = dev->priv;
1114
1115 mutex_lock(&ftl->mutex);
1116 del_timer_sync(&ftl->timer);
1117 cancel_work_sync(&ftl->flush_work);
1118 sm_cache_flush(ftl);
1119 mutex_unlock(&ftl->mutex);
1120 return 0;
1121}
1122
1123/* outside interface: get geometry */
1124static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1125{
1126 struct sm_ftl *ftl = dev->priv;
1127 geo->heads = ftl->heads;
1128 geo->sectors = ftl->sectors;
1129 geo->cylinders = ftl->cylinders;
1130 return 0;
1131}
1132
1133/* external interface: main initialization function */
1134static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1135{
1136 struct mtd_blktrans_dev *trans;
1137 struct sm_ftl *ftl;
1138
1139 /* Allocate & initialize our private structure */
1140 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1141 if (!ftl)
1142 goto error1;
1143
1144
1145 mutex_init(&ftl->mutex);
1146 setup_timer(&ftl->timer, sm_cache_flush_timer, (unsigned long)ftl);
1147 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1148 init_completion(&ftl->erase_completion);
1149
1150 /* Read media information */
1151 if (sm_get_media_info(ftl, mtd)) {
1152 dbg("found unsupported mtd device, aborting");
1153 goto error2;
1154 }
1155
1156
1157 /* Allocate temporary CIS buffer for read retry support */
1158 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1159 if (!ftl->cis_buffer)
1160 goto error2;
1161
1162 /* Allocate zone array, it will be initialized on demand */
1163 ftl->zones = kzalloc(sizeof(struct ftl_zone) * ftl->zone_count,
1164 GFP_KERNEL);
1165 if (!ftl->zones)
1166 goto error3;
1167
1168 /* Allocate the cache*/
1169 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1170
1171 if (!ftl->cache_data)
1172 goto error4;
1173
1174 sm_cache_init(ftl);
1175
1176
1177 /* Allocate upper layer structure and initialize it */
1178 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1179 if (!trans)
1180 goto error5;
1181
1182 ftl->trans = trans;
1183 trans->priv = ftl;
1184
1185 trans->tr = tr;
1186 trans->mtd = mtd;
1187 trans->devnum = -1;
1188 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1189 trans->readonly = ftl->readonly;
1190
1191 if (sm_find_cis(ftl)) {
1192 dbg("CIS not found on mtd device, aborting");
1193 goto error6;
1194 }
1195
1196 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1197 if (!ftl->disk_attributes)
1198 goto error6;
1199 trans->disk_attributes = ftl->disk_attributes;
1200
1201 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1202 (int)(mtd->size / (1024 * 1024)), mtd->index);
1203
1204 dbg("FTL layout:");
1205 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1206 ftl->zone_count, ftl->max_lba,
1207 ftl->zone_size - ftl->max_lba);
1208 dbg("each block consists of %d bytes",
1209 ftl->block_size);
1210
1211
1212 /* Register device*/
1213 if (add_mtd_blktrans_dev(trans)) {
1214 dbg("error in mtdblktrans layer");
1215 goto error6;
1216 }
1217 return;
1218error6:
1219 kfree(trans);
1220error5:
1221 kfree(ftl->cache_data);
1222error4:
1223 kfree(ftl->zones);
1224error3:
1225 kfree(ftl->cis_buffer);
1226error2:
1227 kfree(ftl);
1228error1:
1229 return;
1230}
1231
1232/* main interface: device {surprise,} removal */
1233static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1234{
1235 struct sm_ftl *ftl = dev->priv;
1236 int i;
1237
1238 del_mtd_blktrans_dev(dev);
1239 ftl->trans = NULL;
1240
1241 for (i = 0 ; i < ftl->zone_count; i++) {
1242
1243 if (!ftl->zones[i].initialized)
1244 continue;
1245
1246 kfree(ftl->zones[i].lba_to_phys_table);
1247 kfifo_free(&ftl->zones[i].free_sectors);
1248 }
1249
1250 sm_delete_sysfs_attributes(ftl);
1251 kfree(ftl->cis_buffer);
1252 kfree(ftl->zones);
1253 kfree(ftl->cache_data);
1254 kfree(ftl);
1255}
1256
1257static struct mtd_blktrans_ops sm_ftl_ops = {
1258 .name = "smblk",
1259 .major = -1,
1260 .part_bits = SM_FTL_PARTN_BITS,
1261 .blksize = SM_SECTOR_SIZE,
1262 .getgeo = sm_getgeo,
1263
1264 .add_mtd = sm_add_mtd,
1265 .remove_dev = sm_remove_dev,
1266
1267 .readsect = sm_read,
1268 .writesect = sm_write,
1269
1270 .flush = sm_flush,
1271 .release = sm_release,
1272
1273 .owner = THIS_MODULE,
1274};
1275
1276static __init int sm_module_init(void)
1277{
1278 int error = 0;
1279 cache_flush_workqueue = create_freezable_workqueue("smflush");
1280
1281 if (IS_ERR(cache_flush_workqueue))
1282 return PTR_ERR(cache_flush_workqueue);
1283
1284 error = register_mtd_blktrans(&sm_ftl_ops);
1285 if (error)
1286 destroy_workqueue(cache_flush_workqueue);
1287 return error;
1288
1289}
1290
1291static void __exit sm_module_exit(void)
1292{
1293 destroy_workqueue(cache_flush_workqueue);
1294 deregister_mtd_blktrans(&sm_ftl_ops);
1295}
1296
1297module_init(sm_module_init);
1298module_exit(sm_module_exit);
1299
1300MODULE_LICENSE("GPL");
1301MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1302MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");
1/*
2 * Copyright © 2009 - Maxim Levitsky
3 * SmartMedia/xD translation layer
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/random.h>
13#include <linux/hdreg.h>
14#include <linux/kthread.h>
15#include <linux/freezer.h>
16#include <linux/sysfs.h>
17#include <linux/bitops.h>
18#include <linux/slab.h>
19#include <linux/mtd/nand_ecc.h>
20#include "nand/sm_common.h"
21#include "sm_ftl.h"
22
23
24
25static struct workqueue_struct *cache_flush_workqueue;
26
27static int cache_timeout = 1000;
28module_param(cache_timeout, int, S_IRUGO);
29MODULE_PARM_DESC(cache_timeout,
30 "Timeout (in ms) for cache flush (1000 ms default");
31
32static int debug;
33module_param(debug, int, S_IRUGO | S_IWUSR);
34MODULE_PARM_DESC(debug, "Debug level (0-2)");
35
36
37/* ------------------- sysfs attributes ---------------------------------- */
38struct sm_sysfs_attribute {
39 struct device_attribute dev_attr;
40 char *data;
41 int len;
42};
43
44static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr,
45 char *buf)
46{
47 struct sm_sysfs_attribute *sm_attr =
48 container_of(attr, struct sm_sysfs_attribute, dev_attr);
49
50 strncpy(buf, sm_attr->data, sm_attr->len);
51 return sm_attr->len;
52}
53
54
55#define NUM_ATTRIBUTES 1
56#define SM_CIS_VENDOR_OFFSET 0x59
57static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl)
58{
59 struct attribute_group *attr_group;
60 struct attribute **attributes;
61 struct sm_sysfs_attribute *vendor_attribute;
62 char *vendor;
63
64 vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET,
65 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL);
66 if (!vendor)
67 goto error1;
68
69 /* Initialize sysfs attributes */
70 vendor_attribute =
71 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL);
72 if (!vendor_attribute)
73 goto error2;
74
75 sysfs_attr_init(&vendor_attribute->dev_attr.attr);
76
77 vendor_attribute->data = vendor;
78 vendor_attribute->len = strlen(vendor);
79 vendor_attribute->dev_attr.attr.name = "vendor";
80 vendor_attribute->dev_attr.attr.mode = S_IRUGO;
81 vendor_attribute->dev_attr.show = sm_attr_show;
82
83
84 /* Create array of pointers to the attributes */
85 attributes = kzalloc(sizeof(struct attribute *) * (NUM_ATTRIBUTES + 1),
86 GFP_KERNEL);
87 if (!attributes)
88 goto error3;
89 attributes[0] = &vendor_attribute->dev_attr.attr;
90
91 /* Finally create the attribute group */
92 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
93 if (!attr_group)
94 goto error4;
95 attr_group->attrs = attributes;
96 return attr_group;
97error4:
98 kfree(attributes);
99error3:
100 kfree(vendor_attribute);
101error2:
102 kfree(vendor);
103error1:
104 return NULL;
105}
106
107static void sm_delete_sysfs_attributes(struct sm_ftl *ftl)
108{
109 struct attribute **attributes = ftl->disk_attributes->attrs;
110 int i;
111
112 for (i = 0; attributes[i] ; i++) {
113
114 struct device_attribute *dev_attr = container_of(attributes[i],
115 struct device_attribute, attr);
116
117 struct sm_sysfs_attribute *sm_attr =
118 container_of(dev_attr,
119 struct sm_sysfs_attribute, dev_attr);
120
121 kfree(sm_attr->data);
122 kfree(sm_attr);
123 }
124
125 kfree(ftl->disk_attributes->attrs);
126 kfree(ftl->disk_attributes);
127}
128
129
130/* ----------------------- oob helpers -------------------------------------- */
131
132static int sm_get_lba(uint8_t *lba)
133{
134 /* check fixed bits */
135 if ((lba[0] & 0xF8) != 0x10)
136 return -2;
137
138 /* check parity - endianness doesn't matter */
139 if (hweight16(*(uint16_t *)lba) & 1)
140 return -2;
141
142 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7);
143}
144
145
146/*
147 * Read LBA associated with block
148 * returns -1, if block is erased
149 * returns -2 if error happens
150 */
151static int sm_read_lba(struct sm_oob *oob)
152{
153 static const uint32_t erased_pattern[4] = {
154 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
155
156 uint16_t lba_test;
157 int lba;
158
159 /* First test for erased block */
160 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE))
161 return -1;
162
163 /* Now check is both copies of the LBA differ too much */
164 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2;
165 if (lba_test && !is_power_of_2(lba_test))
166 return -2;
167
168 /* And read it */
169 lba = sm_get_lba(oob->lba_copy1);
170
171 if (lba == -2)
172 lba = sm_get_lba(oob->lba_copy2);
173
174 return lba;
175}
176
177static void sm_write_lba(struct sm_oob *oob, uint16_t lba)
178{
179 uint8_t tmp[2];
180
181 WARN_ON(lba >= 1000);
182
183 tmp[0] = 0x10 | ((lba >> 7) & 0x07);
184 tmp[1] = (lba << 1) & 0xFF;
185
186 if (hweight16(*(uint16_t *)tmp) & 0x01)
187 tmp[1] |= 1;
188
189 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0];
190 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1];
191}
192
193
194/* Make offset from parts */
195static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset)
196{
197 WARN_ON(boffset & (SM_SECTOR_SIZE - 1));
198 WARN_ON(zone < 0 || zone >= ftl->zone_count);
199 WARN_ON(block >= ftl->zone_size);
200 WARN_ON(boffset >= ftl->block_size);
201
202 if (block == -1)
203 return -1;
204
205 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset;
206}
207
208/* Breaks offset into parts */
209static void sm_break_offset(struct sm_ftl *ftl, loff_t loffset,
210 int *zone, int *block, int *boffset)
211{
212 u64 offset = loffset;
213 *boffset = do_div(offset, ftl->block_size);
214 *block = do_div(offset, ftl->max_lba);
215 *zone = offset >= ftl->zone_count ? -1 : offset;
216}
217
218/* ---------------------- low level IO ------------------------------------- */
219
220static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob)
221{
222 uint8_t ecc[3];
223
224 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
225 if (__nand_correct_data(buffer, ecc, oob->ecc1, SM_SMALL_PAGE) < 0)
226 return -EIO;
227
228 buffer += SM_SMALL_PAGE;
229
230 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
231 if (__nand_correct_data(buffer, ecc, oob->ecc2, SM_SMALL_PAGE) < 0)
232 return -EIO;
233 return 0;
234}
235
236/* Reads a sector + oob*/
237static int sm_read_sector(struct sm_ftl *ftl,
238 int zone, int block, int boffset,
239 uint8_t *buffer, struct sm_oob *oob)
240{
241 struct mtd_info *mtd = ftl->trans->mtd;
242 struct mtd_oob_ops ops;
243 struct sm_oob tmp_oob;
244 int ret = -EIO;
245 int try = 0;
246
247 /* FTL can contain -1 entries that are by default filled with bits */
248 if (block == -1) {
249 memset(buffer, 0xFF, SM_SECTOR_SIZE);
250 return 0;
251 }
252
253 /* User might not need the oob, but we do for data verification */
254 if (!oob)
255 oob = &tmp_oob;
256
257 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
258 ops.ooboffs = 0;
259 ops.ooblen = SM_OOB_SIZE;
260 ops.oobbuf = (void *)oob;
261 ops.len = SM_SECTOR_SIZE;
262 ops.datbuf = buffer;
263
264again:
265 if (try++) {
266 /* Avoid infinite recursion on CIS reads, sm_recheck_media
267 won't help anyway */
268 if (zone == 0 && block == ftl->cis_block && boffset ==
269 ftl->cis_boffset)
270 return ret;
271
272 /* Test if media is stable */
273 if (try == 3 || sm_recheck_media(ftl))
274 return ret;
275 }
276
277 /* Unfortunately, oob read will _always_ succeed,
278 despite card removal..... */
279 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
280
281 /* Test for unknown errors */
282 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) {
283 dbg("read of block %d at zone %d, failed due to error (%d)",
284 block, zone, ret);
285 goto again;
286 }
287
288 /* Do a basic test on the oob, to guard against returned garbage */
289 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))
290 goto again;
291
292 /* This should never happen, unless there is a bug in the mtd driver */
293 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
294 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
295
296 if (!buffer)
297 return 0;
298
299 /* Test if sector marked as bad */
300 if (!sm_sector_valid(oob)) {
301 dbg("read of block %d at zone %d, failed because it is marked"
302 " as bad" , block, zone);
303 goto again;
304 }
305
306 /* Test ECC*/
307 if (mtd_is_eccerr(ret) ||
308 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {
309
310 dbg("read of block %d at zone %d, failed due to ECC error",
311 block, zone);
312 goto again;
313 }
314
315 return 0;
316}
317
318/* Writes a sector to media */
319static int sm_write_sector(struct sm_ftl *ftl,
320 int zone, int block, int boffset,
321 uint8_t *buffer, struct sm_oob *oob)
322{
323 struct mtd_oob_ops ops;
324 struct mtd_info *mtd = ftl->trans->mtd;
325 int ret;
326
327 BUG_ON(ftl->readonly);
328
329 if (zone == 0 && (block == ftl->cis_block || block == 0)) {
330 dbg("attempted to write the CIS!");
331 return -EIO;
332 }
333
334 if (ftl->unstable)
335 return -EIO;
336
337 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
338 ops.len = SM_SECTOR_SIZE;
339 ops.datbuf = buffer;
340 ops.ooboffs = 0;
341 ops.ooblen = SM_OOB_SIZE;
342 ops.oobbuf = (void *)oob;
343
344 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
345
346 /* Now we assume that hardware will catch write bitflip errors */
347
348 if (ret) {
349 dbg("write to block %d at zone %d, failed with error %d",
350 block, zone, ret);
351
352 sm_recheck_media(ftl);
353 return ret;
354 }
355
356 /* This should never happen, unless there is a bug in the driver */
357 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
358 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
359
360 return 0;
361}
362
363/* ------------------------ block IO ------------------------------------- */
364
365/* Write a block using data and lba, and invalid sector bitmap */
366static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,
367 int zone, int block, int lba,
368 unsigned long invalid_bitmap)
369{
370 struct sm_oob oob;
371 int boffset;
372 int retry = 0;
373
374 /* Initialize the oob with requested values */
375 memset(&oob, 0xFF, SM_OOB_SIZE);
376 sm_write_lba(&oob, lba);
377restart:
378 if (ftl->unstable)
379 return -EIO;
380
381 for (boffset = 0; boffset < ftl->block_size;
382 boffset += SM_SECTOR_SIZE) {
383
384 oob.data_status = 0xFF;
385
386 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
387
388 sm_printk("sector %d of block at LBA %d of zone %d"
389 " couldn't be read, marking it as invalid",
390 boffset / SM_SECTOR_SIZE, lba, zone);
391
392 oob.data_status = 0;
393 }
394
395 if (ftl->smallpagenand) {
396 __nand_calculate_ecc(buf + boffset,
397 SM_SMALL_PAGE, oob.ecc1);
398
399 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE,
400 SM_SMALL_PAGE, oob.ecc2);
401 }
402 if (!sm_write_sector(ftl, zone, block, boffset,
403 buf + boffset, &oob))
404 continue;
405
406 if (!retry) {
407
408 /* If write fails. try to erase the block */
409 /* This is safe, because we never write in blocks
410 that contain valuable data.
411 This is intended to repair block that are marked
412 as erased, but that isn't fully erased*/
413
414 if (sm_erase_block(ftl, zone, block, 0))
415 return -EIO;
416
417 retry = 1;
418 goto restart;
419 } else {
420 sm_mark_block_bad(ftl, zone, block);
421 return -EIO;
422 }
423 }
424 return 0;
425}
426
427
428/* Mark whole block at offset 'offs' as bad. */
429static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)
430{
431 struct sm_oob oob;
432 int boffset;
433
434 memset(&oob, 0xFF, SM_OOB_SIZE);
435 oob.block_status = 0xF0;
436
437 if (ftl->unstable)
438 return;
439
440 if (sm_recheck_media(ftl))
441 return;
442
443 sm_printk("marking block %d of zone %d as bad", block, zone);
444
445 /* We aren't checking the return value, because we don't care */
446 /* This also fails on fake xD cards, but I guess these won't expose
447 any bad blocks till fail completely */
448 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)
449 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);
450}
451
452/*
453 * Erase a block within a zone
454 * If erase succeeds, it updates free block fifo, otherwise marks block as bad
455 */
456static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
457 int put_free)
458{
459 struct ftl_zone *zone = &ftl->zones[zone_num];
460 struct mtd_info *mtd = ftl->trans->mtd;
461 struct erase_info erase;
462
463 erase.mtd = mtd;
464 erase.callback = sm_erase_callback;
465 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
466 erase.len = ftl->block_size;
467 erase.priv = (u_long)ftl;
468
469 if (ftl->unstable)
470 return -EIO;
471
472 BUG_ON(ftl->readonly);
473
474 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {
475 sm_printk("attempted to erase the CIS!");
476 return -EIO;
477 }
478
479 if (mtd_erase(mtd, &erase)) {
480 sm_printk("erase of block %d in zone %d failed",
481 block, zone_num);
482 goto error;
483 }
484
485 if (erase.state == MTD_ERASE_PENDING)
486 wait_for_completion(&ftl->erase_completion);
487
488 if (erase.state != MTD_ERASE_DONE) {
489 sm_printk("erase of block %d in zone %d failed after wait",
490 block, zone_num);
491 goto error;
492 }
493
494 if (put_free)
495 kfifo_in(&zone->free_sectors,
496 (const unsigned char *)&block, sizeof(block));
497
498 return 0;
499error:
500 sm_mark_block_bad(ftl, zone_num, block);
501 return -EIO;
502}
503
504static void sm_erase_callback(struct erase_info *self)
505{
506 struct sm_ftl *ftl = (struct sm_ftl *)self->priv;
507 complete(&ftl->erase_completion);
508}
509
510/* Thoroughly test that block is valid. */
511static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
512{
513 int boffset;
514 struct sm_oob oob;
515 int lbas[] = { -3, 0, 0, 0 };
516 int i = 0;
517 int test_lba;
518
519
520 /* First just check that block doesn't look fishy */
521 /* Only blocks that are valid or are sliced in two parts, are
522 accepted */
523 for (boffset = 0; boffset < ftl->block_size;
524 boffset += SM_SECTOR_SIZE) {
525
526 /* This shouldn't happen anyway */
527 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
528 return -2;
529
530 test_lba = sm_read_lba(&oob);
531
532 if (lbas[i] != test_lba)
533 lbas[++i] = test_lba;
534
535 /* If we found three different LBAs, something is fishy */
536 if (i == 3)
537 return -EIO;
538 }
539
540 /* If the block is sliced (partially erased usually) erase it */
541 if (i == 2) {
542 sm_erase_block(ftl, zone, block, 1);
543 return 1;
544 }
545
546 return 0;
547}
548
549/* ----------------- media scanning --------------------------------- */
550static const struct chs_entry chs_table[] = {
551 { 1, 125, 4, 4 },
552 { 2, 125, 4, 8 },
553 { 4, 250, 4, 8 },
554 { 8, 250, 4, 16 },
555 { 16, 500, 4, 16 },
556 { 32, 500, 8, 16 },
557 { 64, 500, 8, 32 },
558 { 128, 500, 16, 32 },
559 { 256, 1000, 16, 32 },
560 { 512, 1015, 32, 63 },
561 { 1024, 985, 33, 63 },
562 { 2048, 985, 33, 63 },
563 { 0 },
564};
565
566
567static const uint8_t cis_signature[] = {
568 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
569};
570/* Find out media parameters.
571 * This ideally has to be based on nand id, but for now device size is enough */
572static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
573{
574 int i;
575 int size_in_megs = mtd->size / (1024 * 1024);
576
577 ftl->readonly = mtd->type == MTD_ROM;
578
579 /* Manual settings for very old devices */
580 ftl->zone_count = 1;
581 ftl->smallpagenand = 0;
582
583 switch (size_in_megs) {
584 case 1:
585 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
586 ftl->zone_size = 256;
587 ftl->max_lba = 250;
588 ftl->block_size = 8 * SM_SECTOR_SIZE;
589 ftl->smallpagenand = 1;
590
591 break;
592 case 2:
593 /* 2 MiB flash SmartMedia (256 byte pages)*/
594 if (mtd->writesize == SM_SMALL_PAGE) {
595 ftl->zone_size = 512;
596 ftl->max_lba = 500;
597 ftl->block_size = 8 * SM_SECTOR_SIZE;
598 ftl->smallpagenand = 1;
599 /* 2 MiB rom SmartMedia */
600 } else {
601
602 if (!ftl->readonly)
603 return -ENODEV;
604
605 ftl->zone_size = 256;
606 ftl->max_lba = 250;
607 ftl->block_size = 16 * SM_SECTOR_SIZE;
608 }
609 break;
610 case 4:
611 /* 4 MiB flash/rom SmartMedia device */
612 ftl->zone_size = 512;
613 ftl->max_lba = 500;
614 ftl->block_size = 16 * SM_SECTOR_SIZE;
615 break;
616 case 8:
617 /* 8 MiB flash/rom SmartMedia device */
618 ftl->zone_size = 1024;
619 ftl->max_lba = 1000;
620 ftl->block_size = 16 * SM_SECTOR_SIZE;
621 }
622
623 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
624 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/
625 if (size_in_megs >= 16) {
626 ftl->zone_count = size_in_megs / 16;
627 ftl->zone_size = 1024;
628 ftl->max_lba = 1000;
629 ftl->block_size = 32 * SM_SECTOR_SIZE;
630 }
631
632 /* Test for proper write,erase and oob sizes */
633 if (mtd->erasesize > ftl->block_size)
634 return -ENODEV;
635
636 if (mtd->writesize > SM_SECTOR_SIZE)
637 return -ENODEV;
638
639 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
640 return -ENODEV;
641
642 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
643 return -ENODEV;
644
645 /* We use OOB */
646 if (!mtd_has_oob(mtd))
647 return -ENODEV;
648
649 /* Find geometry information */
650 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
651 if (chs_table[i].size == size_in_megs) {
652 ftl->cylinders = chs_table[i].cyl;
653 ftl->heads = chs_table[i].head;
654 ftl->sectors = chs_table[i].sec;
655 return 0;
656 }
657 }
658
659 sm_printk("media has unknown size : %dMiB", size_in_megs);
660 ftl->cylinders = 985;
661 ftl->heads = 33;
662 ftl->sectors = 63;
663 return 0;
664}
665
666/* Validate the CIS */
667static int sm_read_cis(struct sm_ftl *ftl)
668{
669 struct sm_oob oob;
670
671 if (sm_read_sector(ftl,
672 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
673 return -EIO;
674
675 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
676 return -EIO;
677
678 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
679 cis_signature, sizeof(cis_signature))) {
680 return 0;
681 }
682
683 return -EIO;
684}
685
686/* Scan the media for the CIS */
687static int sm_find_cis(struct sm_ftl *ftl)
688{
689 struct sm_oob oob;
690 int block, boffset;
691 int block_found = 0;
692 int cis_found = 0;
693
694 /* Search for first valid block */
695 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
696
697 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
698 continue;
699
700 if (!sm_block_valid(&oob))
701 continue;
702 block_found = 1;
703 break;
704 }
705
706 if (!block_found)
707 return -EIO;
708
709 /* Search for first valid sector in this block */
710 for (boffset = 0 ; boffset < ftl->block_size;
711 boffset += SM_SECTOR_SIZE) {
712
713 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
714 continue;
715
716 if (!sm_sector_valid(&oob))
717 continue;
718 break;
719 }
720
721 if (boffset == ftl->block_size)
722 return -EIO;
723
724 ftl->cis_block = block;
725 ftl->cis_boffset = boffset;
726 ftl->cis_page_offset = 0;
727
728 cis_found = !sm_read_cis(ftl);
729
730 if (!cis_found) {
731 ftl->cis_page_offset = SM_SMALL_PAGE;
732 cis_found = !sm_read_cis(ftl);
733 }
734
735 if (cis_found) {
736 dbg("CIS block found at offset %x",
737 block * ftl->block_size +
738 boffset + ftl->cis_page_offset);
739 return 0;
740 }
741 return -EIO;
742}
743
744/* Basic test to determine if underlying mtd device if functional */
745static int sm_recheck_media(struct sm_ftl *ftl)
746{
747 if (sm_read_cis(ftl)) {
748
749 if (!ftl->unstable) {
750 sm_printk("media unstable, not allowing writes");
751 ftl->unstable = 1;
752 }
753 return -EIO;
754 }
755 return 0;
756}
757
758/* Initialize a FTL zone */
759static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
760{
761 struct ftl_zone *zone = &ftl->zones[zone_num];
762 struct sm_oob oob;
763 uint16_t block;
764 int lba;
765 int i = 0;
766 int len;
767
768 dbg("initializing zone %d", zone_num);
769
770 /* Allocate memory for FTL table */
771 zone->lba_to_phys_table = kmalloc(ftl->max_lba * 2, GFP_KERNEL);
772
773 if (!zone->lba_to_phys_table)
774 return -ENOMEM;
775 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
776
777
778 /* Allocate memory for free sectors FIFO */
779 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
780 kfree(zone->lba_to_phys_table);
781 return -ENOMEM;
782 }
783
784 /* Now scan the zone */
785 for (block = 0 ; block < ftl->zone_size ; block++) {
786
787 /* Skip blocks till the CIS (including) */
788 if (zone_num == 0 && block <= ftl->cis_block)
789 continue;
790
791 /* Read the oob of first sector */
792 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob))
793 return -EIO;
794
795 /* Test to see if block is erased. It is enough to test
796 first sector, because erase happens in one shot */
797 if (sm_block_erased(&oob)) {
798 kfifo_in(&zone->free_sectors,
799 (unsigned char *)&block, 2);
800 continue;
801 }
802
803 /* If block is marked as bad, skip it */
804 /* This assumes we can trust first sector*/
805 /* However the way the block valid status is defined, ensures
806 very low probability of failure here */
807 if (!sm_block_valid(&oob)) {
808 dbg("PH %04d <-> <marked bad>", block);
809 continue;
810 }
811
812
813 lba = sm_read_lba(&oob);
814
815 /* Invalid LBA means that block is damaged. */
816 /* We can try to erase it, or mark it as bad, but
817 lets leave that to recovery application */
818 if (lba == -2 || lba >= ftl->max_lba) {
819 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
820 continue;
821 }
822
823
824 /* If there is no collision,
825 just put the sector in the FTL table */
826 if (zone->lba_to_phys_table[lba] < 0) {
827 dbg_verbose("PH %04d <-> LBA %04d", block, lba);
828 zone->lba_to_phys_table[lba] = block;
829 continue;
830 }
831
832 sm_printk("collision"
833 " of LBA %d between blocks %d and %d in zone %d",
834 lba, zone->lba_to_phys_table[lba], block, zone_num);
835
836 /* Test that this block is valid*/
837 if (sm_check_block(ftl, zone_num, block))
838 continue;
839
840 /* Test now the old block */
841 if (sm_check_block(ftl, zone_num,
842 zone->lba_to_phys_table[lba])) {
843 zone->lba_to_phys_table[lba] = block;
844 continue;
845 }
846
847 /* If both blocks are valid and share same LBA, it means that
848 they hold different versions of same data. It not
849 known which is more recent, thus just erase one of them
850 */
851 sm_printk("both blocks are valid, erasing the later");
852 sm_erase_block(ftl, zone_num, block, 1);
853 }
854
855 dbg("zone initialized");
856 zone->initialized = 1;
857
858 /* No free sectors, means that the zone is heavily damaged, write won't
859 work, but it can still can be (partially) read */
860 if (!kfifo_len(&zone->free_sectors)) {
861 sm_printk("no free blocks in zone %d", zone_num);
862 return 0;
863 }
864
865 /* Randomize first block we write to */
866 get_random_bytes(&i, 2);
867 i %= (kfifo_len(&zone->free_sectors) / 2);
868
869 while (i--) {
870 len = kfifo_out(&zone->free_sectors,
871 (unsigned char *)&block, 2);
872 WARN_ON(len != 2);
873 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
874 }
875 return 0;
876}
877
878/* Get and automatically initialize an FTL mapping for one zone */
879static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
880{
881 struct ftl_zone *zone;
882 int error;
883
884 BUG_ON(zone_num >= ftl->zone_count);
885 zone = &ftl->zones[zone_num];
886
887 if (!zone->initialized) {
888 error = sm_init_zone(ftl, zone_num);
889
890 if (error)
891 return ERR_PTR(error);
892 }
893 return zone;
894}
895
896
897/* ----------------- cache handling ------------------------------------------*/
898
899/* Initialize the one block cache */
900static void sm_cache_init(struct sm_ftl *ftl)
901{
902 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
903 ftl->cache_clean = 1;
904 ftl->cache_zone = -1;
905 ftl->cache_block = -1;
906 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
907}
908
909/* Put sector in one block cache */
910static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
911{
912 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
913 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
914 ftl->cache_clean = 0;
915}
916
917/* Read a sector from the cache */
918static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
919{
920 if (test_bit(boffset / SM_SECTOR_SIZE,
921 &ftl->cache_data_invalid_bitmap))
922 return -1;
923
924 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
925 return 0;
926}
927
928/* Write the cache to hardware */
929static int sm_cache_flush(struct sm_ftl *ftl)
930{
931 struct ftl_zone *zone;
932
933 int sector_num;
934 uint16_t write_sector;
935 int zone_num = ftl->cache_zone;
936 int block_num;
937
938 if (ftl->cache_clean)
939 return 0;
940
941 if (ftl->unstable)
942 return -EIO;
943
944 BUG_ON(zone_num < 0);
945 zone = &ftl->zones[zone_num];
946 block_num = zone->lba_to_phys_table[ftl->cache_block];
947
948
949 /* Try to read all unread areas of the cache block*/
950 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
951 ftl->block_size / SM_SECTOR_SIZE) {
952
953 if (!sm_read_sector(ftl,
954 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
955 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
956 clear_bit(sector_num,
957 &ftl->cache_data_invalid_bitmap);
958 }
959restart:
960
961 if (ftl->unstable)
962 return -EIO;
963
964 /* If there are no spare blocks, */
965 /* we could still continue by erasing/writing the current block,
966 but for such worn out media it doesn't worth the trouble,
967 and the dangers */
968 if (kfifo_out(&zone->free_sectors,
969 (unsigned char *)&write_sector, 2) != 2) {
970 dbg("no free sectors for write!");
971 return -EIO;
972 }
973
974
975 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
976 ftl->cache_block, ftl->cache_data_invalid_bitmap))
977 goto restart;
978
979 /* Update the FTL table */
980 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
981
982 /* Write succesfull, so erase and free the old block */
983 if (block_num > 0)
984 sm_erase_block(ftl, zone_num, block_num, 1);
985
986 sm_cache_init(ftl);
987 return 0;
988}
989
990
991/* flush timer, runs a second after last write */
992static void sm_cache_flush_timer(unsigned long data)
993{
994 struct sm_ftl *ftl = (struct sm_ftl *)data;
995 queue_work(cache_flush_workqueue, &ftl->flush_work);
996}
997
998/* cache flush work, kicked by timer */
999static void sm_cache_flush_work(struct work_struct *work)
1000{
1001 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
1002 mutex_lock(&ftl->mutex);
1003 sm_cache_flush(ftl);
1004 mutex_unlock(&ftl->mutex);
1005 return;
1006}
1007
1008/* ---------------- outside interface -------------------------------------- */
1009
1010/* outside interface: read a sector */
1011static int sm_read(struct mtd_blktrans_dev *dev,
1012 unsigned long sect_no, char *buf)
1013{
1014 struct sm_ftl *ftl = dev->priv;
1015 struct ftl_zone *zone;
1016 int error = 0, in_cache = 0;
1017 int zone_num, block, boffset;
1018
1019 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1020 mutex_lock(&ftl->mutex);
1021
1022
1023 zone = sm_get_zone(ftl, zone_num);
1024 if (IS_ERR(zone)) {
1025 error = PTR_ERR(zone);
1026 goto unlock;
1027 }
1028
1029 /* Have to look at cache first */
1030 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1031 in_cache = 1;
1032 if (!sm_cache_get(ftl, buf, boffset))
1033 goto unlock;
1034 }
1035
1036 /* Translate the block and return if doesn't exist in the table */
1037 block = zone->lba_to_phys_table[block];
1038
1039 if (block == -1) {
1040 memset(buf, 0xFF, SM_SECTOR_SIZE);
1041 goto unlock;
1042 }
1043
1044 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1045 error = -EIO;
1046 goto unlock;
1047 }
1048
1049 if (in_cache)
1050 sm_cache_put(ftl, buf, boffset);
1051unlock:
1052 mutex_unlock(&ftl->mutex);
1053 return error;
1054}
1055
1056/* outside interface: write a sector */
1057static int sm_write(struct mtd_blktrans_dev *dev,
1058 unsigned long sec_no, char *buf)
1059{
1060 struct sm_ftl *ftl = dev->priv;
1061 struct ftl_zone *zone;
1062 int error = 0, zone_num, block, boffset;
1063
1064 BUG_ON(ftl->readonly);
1065 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1066
1067 /* No need in flush thread running now */
1068 del_timer(&ftl->timer);
1069 mutex_lock(&ftl->mutex);
1070
1071 zone = sm_get_zone(ftl, zone_num);
1072 if (IS_ERR(zone)) {
1073 error = PTR_ERR(zone);
1074 goto unlock;
1075 }
1076
1077 /* If entry is not in cache, flush it */
1078 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1079
1080 error = sm_cache_flush(ftl);
1081 if (error)
1082 goto unlock;
1083
1084 ftl->cache_block = block;
1085 ftl->cache_zone = zone_num;
1086 }
1087
1088 sm_cache_put(ftl, buf, boffset);
1089unlock:
1090 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1091 mutex_unlock(&ftl->mutex);
1092 return error;
1093}
1094
1095/* outside interface: flush everything */
1096static int sm_flush(struct mtd_blktrans_dev *dev)
1097{
1098 struct sm_ftl *ftl = dev->priv;
1099 int retval;
1100
1101 mutex_lock(&ftl->mutex);
1102 retval = sm_cache_flush(ftl);
1103 mutex_unlock(&ftl->mutex);
1104 return retval;
1105}
1106
1107/* outside interface: device is released */
1108static void sm_release(struct mtd_blktrans_dev *dev)
1109{
1110 struct sm_ftl *ftl = dev->priv;
1111
1112 mutex_lock(&ftl->mutex);
1113 del_timer_sync(&ftl->timer);
1114 cancel_work_sync(&ftl->flush_work);
1115 sm_cache_flush(ftl);
1116 mutex_unlock(&ftl->mutex);
1117}
1118
1119/* outside interface: get geometry */
1120static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1121{
1122 struct sm_ftl *ftl = dev->priv;
1123 geo->heads = ftl->heads;
1124 geo->sectors = ftl->sectors;
1125 geo->cylinders = ftl->cylinders;
1126 return 0;
1127}
1128
1129/* external interface: main initialization function */
1130static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1131{
1132 struct mtd_blktrans_dev *trans;
1133 struct sm_ftl *ftl;
1134
1135 /* Allocate & initialize our private structure */
1136 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1137 if (!ftl)
1138 goto error1;
1139
1140
1141 mutex_init(&ftl->mutex);
1142 setup_timer(&ftl->timer, sm_cache_flush_timer, (unsigned long)ftl);
1143 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1144 init_completion(&ftl->erase_completion);
1145
1146 /* Read media information */
1147 if (sm_get_media_info(ftl, mtd)) {
1148 dbg("found unsupported mtd device, aborting");
1149 goto error2;
1150 }
1151
1152
1153 /* Allocate temporary CIS buffer for read retry support */
1154 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1155 if (!ftl->cis_buffer)
1156 goto error2;
1157
1158 /* Allocate zone array, it will be initialized on demand */
1159 ftl->zones = kzalloc(sizeof(struct ftl_zone) * ftl->zone_count,
1160 GFP_KERNEL);
1161 if (!ftl->zones)
1162 goto error3;
1163
1164 /* Allocate the cache*/
1165 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1166
1167 if (!ftl->cache_data)
1168 goto error4;
1169
1170 sm_cache_init(ftl);
1171
1172
1173 /* Allocate upper layer structure and initialize it */
1174 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1175 if (!trans)
1176 goto error5;
1177
1178 ftl->trans = trans;
1179 trans->priv = ftl;
1180
1181 trans->tr = tr;
1182 trans->mtd = mtd;
1183 trans->devnum = -1;
1184 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1185 trans->readonly = ftl->readonly;
1186
1187 if (sm_find_cis(ftl)) {
1188 dbg("CIS not found on mtd device, aborting");
1189 goto error6;
1190 }
1191
1192 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1193 if (!ftl->disk_attributes)
1194 goto error6;
1195 trans->disk_attributes = ftl->disk_attributes;
1196
1197 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1198 (int)(mtd->size / (1024 * 1024)), mtd->index);
1199
1200 dbg("FTL layout:");
1201 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1202 ftl->zone_count, ftl->max_lba,
1203 ftl->zone_size - ftl->max_lba);
1204 dbg("each block consists of %d bytes",
1205 ftl->block_size);
1206
1207
1208 /* Register device*/
1209 if (add_mtd_blktrans_dev(trans)) {
1210 dbg("error in mtdblktrans layer");
1211 goto error6;
1212 }
1213 return;
1214error6:
1215 kfree(trans);
1216error5:
1217 kfree(ftl->cache_data);
1218error4:
1219 kfree(ftl->zones);
1220error3:
1221 kfree(ftl->cis_buffer);
1222error2:
1223 kfree(ftl);
1224error1:
1225 return;
1226}
1227
1228/* main interface: device {surprise,} removal */
1229static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1230{
1231 struct sm_ftl *ftl = dev->priv;
1232 int i;
1233
1234 del_mtd_blktrans_dev(dev);
1235 ftl->trans = NULL;
1236
1237 for (i = 0 ; i < ftl->zone_count; i++) {
1238
1239 if (!ftl->zones[i].initialized)
1240 continue;
1241
1242 kfree(ftl->zones[i].lba_to_phys_table);
1243 kfifo_free(&ftl->zones[i].free_sectors);
1244 }
1245
1246 sm_delete_sysfs_attributes(ftl);
1247 kfree(ftl->cis_buffer);
1248 kfree(ftl->zones);
1249 kfree(ftl->cache_data);
1250 kfree(ftl);
1251}
1252
1253static struct mtd_blktrans_ops sm_ftl_ops = {
1254 .name = "smblk",
1255 .major = 0,
1256 .part_bits = SM_FTL_PARTN_BITS,
1257 .blksize = SM_SECTOR_SIZE,
1258 .getgeo = sm_getgeo,
1259
1260 .add_mtd = sm_add_mtd,
1261 .remove_dev = sm_remove_dev,
1262
1263 .readsect = sm_read,
1264 .writesect = sm_write,
1265
1266 .flush = sm_flush,
1267 .release = sm_release,
1268
1269 .owner = THIS_MODULE,
1270};
1271
1272static __init int sm_module_init(void)
1273{
1274 int error = 0;
1275
1276 cache_flush_workqueue = create_freezable_workqueue("smflush");
1277 if (!cache_flush_workqueue)
1278 return -ENOMEM;
1279
1280 error = register_mtd_blktrans(&sm_ftl_ops);
1281 if (error)
1282 destroy_workqueue(cache_flush_workqueue);
1283 return error;
1284
1285}
1286
1287static void __exit sm_module_exit(void)
1288{
1289 destroy_workqueue(cache_flush_workqueue);
1290 deregister_mtd_blktrans(&sm_ftl_ops);
1291}
1292
1293module_init(sm_module_init);
1294module_exit(sm_module_exit);
1295
1296MODULE_LICENSE("GPL");
1297MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1298MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");