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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// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright © 2009 - Maxim Levitsky
4 * SmartMedia/xD translation layer
5 */
6
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/random.h>
10#include <linux/hdreg.h>
11#include <linux/kthread.h>
12#include <linux/freezer.h>
13#include <linux/sysfs.h>
14#include <linux/bitops.h>
15#include <linux/slab.h>
16#include <linux/mtd/nand_ecc.h>
17#include "nand/raw/sm_common.h"
18#include "sm_ftl.h"
19
20
21
22static struct workqueue_struct *cache_flush_workqueue;
23
24static int cache_timeout = 1000;
25module_param(cache_timeout, int, S_IRUGO);
26MODULE_PARM_DESC(cache_timeout,
27 "Timeout (in ms) for cache flush (1000 ms default");
28
29static int debug;
30module_param(debug, int, S_IRUGO | S_IWUSR);
31MODULE_PARM_DESC(debug, "Debug level (0-2)");
32
33
34/* ------------------- sysfs attributes ---------------------------------- */
35struct sm_sysfs_attribute {
36 struct device_attribute dev_attr;
37 char *data;
38 int len;
39};
40
41static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr,
42 char *buf)
43{
44 struct sm_sysfs_attribute *sm_attr =
45 container_of(attr, struct sm_sysfs_attribute, dev_attr);
46
47 strncpy(buf, sm_attr->data, sm_attr->len);
48 return sm_attr->len;
49}
50
51
52#define NUM_ATTRIBUTES 1
53#define SM_CIS_VENDOR_OFFSET 0x59
54static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl)
55{
56 struct attribute_group *attr_group;
57 struct attribute **attributes;
58 struct sm_sysfs_attribute *vendor_attribute;
59 char *vendor;
60
61 vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET,
62 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL);
63 if (!vendor)
64 goto error1;
65
66 /* Initialize sysfs attributes */
67 vendor_attribute =
68 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL);
69 if (!vendor_attribute)
70 goto error2;
71
72 sysfs_attr_init(&vendor_attribute->dev_attr.attr);
73
74 vendor_attribute->data = vendor;
75 vendor_attribute->len = strlen(vendor);
76 vendor_attribute->dev_attr.attr.name = "vendor";
77 vendor_attribute->dev_attr.attr.mode = S_IRUGO;
78 vendor_attribute->dev_attr.show = sm_attr_show;
79
80
81 /* Create array of pointers to the attributes */
82 attributes = kcalloc(NUM_ATTRIBUTES + 1, sizeof(struct attribute *),
83 GFP_KERNEL);
84 if (!attributes)
85 goto error3;
86 attributes[0] = &vendor_attribute->dev_attr.attr;
87
88 /* Finally create the attribute group */
89 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
90 if (!attr_group)
91 goto error4;
92 attr_group->attrs = attributes;
93 return attr_group;
94error4:
95 kfree(attributes);
96error3:
97 kfree(vendor_attribute);
98error2:
99 kfree(vendor);
100error1:
101 return NULL;
102}
103
104static void sm_delete_sysfs_attributes(struct sm_ftl *ftl)
105{
106 struct attribute **attributes = ftl->disk_attributes->attrs;
107 int i;
108
109 for (i = 0; attributes[i] ; i++) {
110
111 struct device_attribute *dev_attr = container_of(attributes[i],
112 struct device_attribute, attr);
113
114 struct sm_sysfs_attribute *sm_attr =
115 container_of(dev_attr,
116 struct sm_sysfs_attribute, dev_attr);
117
118 kfree(sm_attr->data);
119 kfree(sm_attr);
120 }
121
122 kfree(ftl->disk_attributes->attrs);
123 kfree(ftl->disk_attributes);
124}
125
126
127/* ----------------------- oob helpers -------------------------------------- */
128
129static int sm_get_lba(uint8_t *lba)
130{
131 /* check fixed bits */
132 if ((lba[0] & 0xF8) != 0x10)
133 return -2;
134
135 /* check parity - endianness doesn't matter */
136 if (hweight16(*(uint16_t *)lba) & 1)
137 return -2;
138
139 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7);
140}
141
142
143/*
144 * Read LBA associated with block
145 * returns -1, if block is erased
146 * returns -2 if error happens
147 */
148static int sm_read_lba(struct sm_oob *oob)
149{
150 static const uint32_t erased_pattern[4] = {
151 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
152
153 uint16_t lba_test;
154 int lba;
155
156 /* First test for erased block */
157 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE))
158 return -1;
159
160 /* Now check is both copies of the LBA differ too much */
161 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2;
162 if (lba_test && !is_power_of_2(lba_test))
163 return -2;
164
165 /* And read it */
166 lba = sm_get_lba(oob->lba_copy1);
167
168 if (lba == -2)
169 lba = sm_get_lba(oob->lba_copy2);
170
171 return lba;
172}
173
174static void sm_write_lba(struct sm_oob *oob, uint16_t lba)
175{
176 uint8_t tmp[2];
177
178 WARN_ON(lba >= 1000);
179
180 tmp[0] = 0x10 | ((lba >> 7) & 0x07);
181 tmp[1] = (lba << 1) & 0xFF;
182
183 if (hweight16(*(uint16_t *)tmp) & 0x01)
184 tmp[1] |= 1;
185
186 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0];
187 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1];
188}
189
190
191/* Make offset from parts */
192static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset)
193{
194 WARN_ON(boffset & (SM_SECTOR_SIZE - 1));
195 WARN_ON(zone < 0 || zone >= ftl->zone_count);
196 WARN_ON(block >= ftl->zone_size);
197 WARN_ON(boffset >= ftl->block_size);
198
199 if (block == -1)
200 return -1;
201
202 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset;
203}
204
205/* Breaks offset into parts */
206static void sm_break_offset(struct sm_ftl *ftl, loff_t loffset,
207 int *zone, int *block, int *boffset)
208{
209 u64 offset = loffset;
210 *boffset = do_div(offset, ftl->block_size);
211 *block = do_div(offset, ftl->max_lba);
212 *zone = offset >= ftl->zone_count ? -1 : offset;
213}
214
215/* ---------------------- low level IO ------------------------------------- */
216
217static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob)
218{
219 uint8_t ecc[3];
220
221 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc,
222 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
223 if (__nand_correct_data(buffer, ecc, oob->ecc1, SM_SMALL_PAGE,
224 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC)) < 0)
225 return -EIO;
226
227 buffer += SM_SMALL_PAGE;
228
229 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc,
230 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
231 if (__nand_correct_data(buffer, ecc, oob->ecc2, SM_SMALL_PAGE,
232 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC)) < 0)
233 return -EIO;
234 return 0;
235}
236
237/* Reads a sector + oob*/
238static int sm_read_sector(struct sm_ftl *ftl,
239 int zone, int block, int boffset,
240 uint8_t *buffer, struct sm_oob *oob)
241{
242 struct mtd_info *mtd = ftl->trans->mtd;
243 struct mtd_oob_ops ops;
244 struct sm_oob tmp_oob;
245 int ret = -EIO;
246 int try = 0;
247
248 /* FTL can contain -1 entries that are by default filled with bits */
249 if (block == -1) {
250 memset(buffer, 0xFF, SM_SECTOR_SIZE);
251 return 0;
252 }
253
254 /* User might not need the oob, but we do for data verification */
255 if (!oob)
256 oob = &tmp_oob;
257
258 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
259 ops.ooboffs = 0;
260 ops.ooblen = SM_OOB_SIZE;
261 ops.oobbuf = (void *)oob;
262 ops.len = SM_SECTOR_SIZE;
263 ops.datbuf = buffer;
264
265again:
266 if (try++) {
267 /* Avoid infinite recursion on CIS reads, sm_recheck_media
268 won't help anyway */
269 if (zone == 0 && block == ftl->cis_block && boffset ==
270 ftl->cis_boffset)
271 return ret;
272
273 /* Test if media is stable */
274 if (try == 3 || sm_recheck_media(ftl))
275 return ret;
276 }
277
278 /* Unfortunately, oob read will _always_ succeed,
279 despite card removal..... */
280 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
281
282 /* Test for unknown errors */
283 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) {
284 dbg("read of block %d at zone %d, failed due to error (%d)",
285 block, zone, ret);
286 goto again;
287 }
288
289 /* Do a basic test on the oob, to guard against returned garbage */
290 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))
291 goto again;
292
293 /* This should never happen, unless there is a bug in the mtd driver */
294 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
295 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
296
297 if (!buffer)
298 return 0;
299
300 /* Test if sector marked as bad */
301 if (!sm_sector_valid(oob)) {
302 dbg("read of block %d at zone %d, failed because it is marked"
303 " as bad" , block, zone);
304 goto again;
305 }
306
307 /* Test ECC*/
308 if (mtd_is_eccerr(ret) ||
309 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {
310
311 dbg("read of block %d at zone %d, failed due to ECC error",
312 block, zone);
313 goto again;
314 }
315
316 return 0;
317}
318
319/* Writes a sector to media */
320static int sm_write_sector(struct sm_ftl *ftl,
321 int zone, int block, int boffset,
322 uint8_t *buffer, struct sm_oob *oob)
323{
324 struct mtd_oob_ops ops;
325 struct mtd_info *mtd = ftl->trans->mtd;
326 int ret;
327
328 BUG_ON(ftl->readonly);
329
330 if (zone == 0 && (block == ftl->cis_block || block == 0)) {
331 dbg("attempted to write the CIS!");
332 return -EIO;
333 }
334
335 if (ftl->unstable)
336 return -EIO;
337
338 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
339 ops.len = SM_SECTOR_SIZE;
340 ops.datbuf = buffer;
341 ops.ooboffs = 0;
342 ops.ooblen = SM_OOB_SIZE;
343 ops.oobbuf = (void *)oob;
344
345 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
346
347 /* Now we assume that hardware will catch write bitflip errors */
348
349 if (ret) {
350 dbg("write to block %d at zone %d, failed with error %d",
351 block, zone, ret);
352
353 sm_recheck_media(ftl);
354 return ret;
355 }
356
357 /* This should never happen, unless there is a bug in the driver */
358 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
359 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
360
361 return 0;
362}
363
364/* ------------------------ block IO ------------------------------------- */
365
366/* Write a block using data and lba, and invalid sector bitmap */
367static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,
368 int zone, int block, int lba,
369 unsigned long invalid_bitmap)
370{
371 struct sm_oob oob;
372 int boffset;
373 int retry = 0;
374
375 /* Initialize the oob with requested values */
376 memset(&oob, 0xFF, SM_OOB_SIZE);
377 sm_write_lba(&oob, lba);
378restart:
379 if (ftl->unstable)
380 return -EIO;
381
382 for (boffset = 0; boffset < ftl->block_size;
383 boffset += SM_SECTOR_SIZE) {
384
385 oob.data_status = 0xFF;
386
387 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
388
389 sm_printk("sector %d of block at LBA %d of zone %d"
390 " couldn't be read, marking it as invalid",
391 boffset / SM_SECTOR_SIZE, lba, zone);
392
393 oob.data_status = 0;
394 }
395
396 if (ftl->smallpagenand) {
397 __nand_calculate_ecc(buf + boffset, SM_SMALL_PAGE,
398 oob.ecc1,
399 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
400
401 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE,
402 SM_SMALL_PAGE, oob.ecc2,
403 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
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 completely */
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 succeeds, 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.addr = sm_mkoffset(ftl, zone_num, block, 0);
467 erase.len = ftl->block_size;
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 (put_free)
486 kfifo_in(&zone->free_sectors,
487 (const unsigned char *)&block, sizeof(block));
488
489 return 0;
490error:
491 sm_mark_block_bad(ftl, zone_num, block);
492 return -EIO;
493}
494
495/* Thoroughly test that block is valid. */
496static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
497{
498 int boffset;
499 struct sm_oob oob;
500 int lbas[] = { -3, 0, 0, 0 };
501 int i = 0;
502 int test_lba;
503
504
505 /* First just check that block doesn't look fishy */
506 /* Only blocks that are valid or are sliced in two parts, are
507 accepted */
508 for (boffset = 0; boffset < ftl->block_size;
509 boffset += SM_SECTOR_SIZE) {
510
511 /* This shouldn't happen anyway */
512 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
513 return -2;
514
515 test_lba = sm_read_lba(&oob);
516
517 if (lbas[i] != test_lba)
518 lbas[++i] = test_lba;
519
520 /* If we found three different LBAs, something is fishy */
521 if (i == 3)
522 return -EIO;
523 }
524
525 /* If the block is sliced (partially erased usually) erase it */
526 if (i == 2) {
527 sm_erase_block(ftl, zone, block, 1);
528 return 1;
529 }
530
531 return 0;
532}
533
534/* ----------------- media scanning --------------------------------- */
535static const struct chs_entry chs_table[] = {
536 { 1, 125, 4, 4 },
537 { 2, 125, 4, 8 },
538 { 4, 250, 4, 8 },
539 { 8, 250, 4, 16 },
540 { 16, 500, 4, 16 },
541 { 32, 500, 8, 16 },
542 { 64, 500, 8, 32 },
543 { 128, 500, 16, 32 },
544 { 256, 1000, 16, 32 },
545 { 512, 1015, 32, 63 },
546 { 1024, 985, 33, 63 },
547 { 2048, 985, 33, 63 },
548 { 0 },
549};
550
551
552static const uint8_t cis_signature[] = {
553 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
554};
555/* Find out media parameters.
556 * This ideally has to be based on nand id, but for now device size is enough */
557static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
558{
559 int i;
560 int size_in_megs = mtd->size / (1024 * 1024);
561
562 ftl->readonly = mtd->type == MTD_ROM;
563
564 /* Manual settings for very old devices */
565 ftl->zone_count = 1;
566 ftl->smallpagenand = 0;
567
568 switch (size_in_megs) {
569 case 1:
570 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
571 ftl->zone_size = 256;
572 ftl->max_lba = 250;
573 ftl->block_size = 8 * SM_SECTOR_SIZE;
574 ftl->smallpagenand = 1;
575
576 break;
577 case 2:
578 /* 2 MiB flash SmartMedia (256 byte pages)*/
579 if (mtd->writesize == SM_SMALL_PAGE) {
580 ftl->zone_size = 512;
581 ftl->max_lba = 500;
582 ftl->block_size = 8 * SM_SECTOR_SIZE;
583 ftl->smallpagenand = 1;
584 /* 2 MiB rom SmartMedia */
585 } else {
586
587 if (!ftl->readonly)
588 return -ENODEV;
589
590 ftl->zone_size = 256;
591 ftl->max_lba = 250;
592 ftl->block_size = 16 * SM_SECTOR_SIZE;
593 }
594 break;
595 case 4:
596 /* 4 MiB flash/rom SmartMedia device */
597 ftl->zone_size = 512;
598 ftl->max_lba = 500;
599 ftl->block_size = 16 * SM_SECTOR_SIZE;
600 break;
601 case 8:
602 /* 8 MiB flash/rom SmartMedia device */
603 ftl->zone_size = 1024;
604 ftl->max_lba = 1000;
605 ftl->block_size = 16 * SM_SECTOR_SIZE;
606 }
607
608 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
609 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/
610 if (size_in_megs >= 16) {
611 ftl->zone_count = size_in_megs / 16;
612 ftl->zone_size = 1024;
613 ftl->max_lba = 1000;
614 ftl->block_size = 32 * SM_SECTOR_SIZE;
615 }
616
617 /* Test for proper write,erase and oob sizes */
618 if (mtd->erasesize > ftl->block_size)
619 return -ENODEV;
620
621 if (mtd->writesize > SM_SECTOR_SIZE)
622 return -ENODEV;
623
624 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
625 return -ENODEV;
626
627 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
628 return -ENODEV;
629
630 /* We use OOB */
631 if (!mtd_has_oob(mtd))
632 return -ENODEV;
633
634 /* Find geometry information */
635 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
636 if (chs_table[i].size == size_in_megs) {
637 ftl->cylinders = chs_table[i].cyl;
638 ftl->heads = chs_table[i].head;
639 ftl->sectors = chs_table[i].sec;
640 return 0;
641 }
642 }
643
644 sm_printk("media has unknown size : %dMiB", size_in_megs);
645 ftl->cylinders = 985;
646 ftl->heads = 33;
647 ftl->sectors = 63;
648 return 0;
649}
650
651/* Validate the CIS */
652static int sm_read_cis(struct sm_ftl *ftl)
653{
654 struct sm_oob oob;
655
656 if (sm_read_sector(ftl,
657 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
658 return -EIO;
659
660 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
661 return -EIO;
662
663 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
664 cis_signature, sizeof(cis_signature))) {
665 return 0;
666 }
667
668 return -EIO;
669}
670
671/* Scan the media for the CIS */
672static int sm_find_cis(struct sm_ftl *ftl)
673{
674 struct sm_oob oob;
675 int block, boffset;
676 int block_found = 0;
677 int cis_found = 0;
678
679 /* Search for first valid block */
680 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
681
682 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
683 continue;
684
685 if (!sm_block_valid(&oob))
686 continue;
687 block_found = 1;
688 break;
689 }
690
691 if (!block_found)
692 return -EIO;
693
694 /* Search for first valid sector in this block */
695 for (boffset = 0 ; boffset < ftl->block_size;
696 boffset += SM_SECTOR_SIZE) {
697
698 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
699 continue;
700
701 if (!sm_sector_valid(&oob))
702 continue;
703 break;
704 }
705
706 if (boffset == ftl->block_size)
707 return -EIO;
708
709 ftl->cis_block = block;
710 ftl->cis_boffset = boffset;
711 ftl->cis_page_offset = 0;
712
713 cis_found = !sm_read_cis(ftl);
714
715 if (!cis_found) {
716 ftl->cis_page_offset = SM_SMALL_PAGE;
717 cis_found = !sm_read_cis(ftl);
718 }
719
720 if (cis_found) {
721 dbg("CIS block found at offset %x",
722 block * ftl->block_size +
723 boffset + ftl->cis_page_offset);
724 return 0;
725 }
726 return -EIO;
727}
728
729/* Basic test to determine if underlying mtd device if functional */
730static int sm_recheck_media(struct sm_ftl *ftl)
731{
732 if (sm_read_cis(ftl)) {
733
734 if (!ftl->unstable) {
735 sm_printk("media unstable, not allowing writes");
736 ftl->unstable = 1;
737 }
738 return -EIO;
739 }
740 return 0;
741}
742
743/* Initialize a FTL zone */
744static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
745{
746 struct ftl_zone *zone = &ftl->zones[zone_num];
747 struct sm_oob oob;
748 uint16_t block;
749 int lba;
750 int i = 0;
751 int len;
752
753 dbg("initializing zone %d", zone_num);
754
755 /* Allocate memory for FTL table */
756 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL);
757
758 if (!zone->lba_to_phys_table)
759 return -ENOMEM;
760 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
761
762
763 /* Allocate memory for free sectors FIFO */
764 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
765 kfree(zone->lba_to_phys_table);
766 return -ENOMEM;
767 }
768
769 /* Now scan the zone */
770 for (block = 0 ; block < ftl->zone_size ; block++) {
771
772 /* Skip blocks till the CIS (including) */
773 if (zone_num == 0 && block <= ftl->cis_block)
774 continue;
775
776 /* Read the oob of first sector */
777 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) {
778 kfifo_free(&zone->free_sectors);
779 kfree(zone->lba_to_phys_table);
780 return -EIO;
781 }
782
783 /* Test to see if block is erased. It is enough to test
784 first sector, because erase happens in one shot */
785 if (sm_block_erased(&oob)) {
786 kfifo_in(&zone->free_sectors,
787 (unsigned char *)&block, 2);
788 continue;
789 }
790
791 /* If block is marked as bad, skip it */
792 /* This assumes we can trust first sector*/
793 /* However the way the block valid status is defined, ensures
794 very low probability of failure here */
795 if (!sm_block_valid(&oob)) {
796 dbg("PH %04d <-> <marked bad>", block);
797 continue;
798 }
799
800
801 lba = sm_read_lba(&oob);
802
803 /* Invalid LBA means that block is damaged. */
804 /* We can try to erase it, or mark it as bad, but
805 lets leave that to recovery application */
806 if (lba == -2 || lba >= ftl->max_lba) {
807 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
808 continue;
809 }
810
811
812 /* If there is no collision,
813 just put the sector in the FTL table */
814 if (zone->lba_to_phys_table[lba] < 0) {
815 dbg_verbose("PH %04d <-> LBA %04d", block, lba);
816 zone->lba_to_phys_table[lba] = block;
817 continue;
818 }
819
820 sm_printk("collision"
821 " of LBA %d between blocks %d and %d in zone %d",
822 lba, zone->lba_to_phys_table[lba], block, zone_num);
823
824 /* Test that this block is valid*/
825 if (sm_check_block(ftl, zone_num, block))
826 continue;
827
828 /* Test now the old block */
829 if (sm_check_block(ftl, zone_num,
830 zone->lba_to_phys_table[lba])) {
831 zone->lba_to_phys_table[lba] = block;
832 continue;
833 }
834
835 /* If both blocks are valid and share same LBA, it means that
836 they hold different versions of same data. It not
837 known which is more recent, thus just erase one of them
838 */
839 sm_printk("both blocks are valid, erasing the later");
840 sm_erase_block(ftl, zone_num, block, 1);
841 }
842
843 dbg("zone initialized");
844 zone->initialized = 1;
845
846 /* No free sectors, means that the zone is heavily damaged, write won't
847 work, but it can still can be (partially) read */
848 if (!kfifo_len(&zone->free_sectors)) {
849 sm_printk("no free blocks in zone %d", zone_num);
850 return 0;
851 }
852
853 /* Randomize first block we write to */
854 get_random_bytes(&i, 2);
855 i %= (kfifo_len(&zone->free_sectors) / 2);
856
857 while (i--) {
858 len = kfifo_out(&zone->free_sectors,
859 (unsigned char *)&block, 2);
860 WARN_ON(len != 2);
861 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
862 }
863 return 0;
864}
865
866/* Get and automatically initialize an FTL mapping for one zone */
867static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
868{
869 struct ftl_zone *zone;
870 int error;
871
872 BUG_ON(zone_num >= ftl->zone_count);
873 zone = &ftl->zones[zone_num];
874
875 if (!zone->initialized) {
876 error = sm_init_zone(ftl, zone_num);
877
878 if (error)
879 return ERR_PTR(error);
880 }
881 return zone;
882}
883
884
885/* ----------------- cache handling ------------------------------------------*/
886
887/* Initialize the one block cache */
888static void sm_cache_init(struct sm_ftl *ftl)
889{
890 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
891 ftl->cache_clean = 1;
892 ftl->cache_zone = -1;
893 ftl->cache_block = -1;
894 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
895}
896
897/* Put sector in one block cache */
898static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
899{
900 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
901 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
902 ftl->cache_clean = 0;
903}
904
905/* Read a sector from the cache */
906static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
907{
908 if (test_bit(boffset / SM_SECTOR_SIZE,
909 &ftl->cache_data_invalid_bitmap))
910 return -1;
911
912 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
913 return 0;
914}
915
916/* Write the cache to hardware */
917static int sm_cache_flush(struct sm_ftl *ftl)
918{
919 struct ftl_zone *zone;
920
921 int sector_num;
922 uint16_t write_sector;
923 int zone_num = ftl->cache_zone;
924 int block_num;
925
926 if (ftl->cache_clean)
927 return 0;
928
929 if (ftl->unstable)
930 return -EIO;
931
932 BUG_ON(zone_num < 0);
933 zone = &ftl->zones[zone_num];
934 block_num = zone->lba_to_phys_table[ftl->cache_block];
935
936
937 /* Try to read all unread areas of the cache block*/
938 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
939 ftl->block_size / SM_SECTOR_SIZE) {
940
941 if (!sm_read_sector(ftl,
942 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
943 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
944 clear_bit(sector_num,
945 &ftl->cache_data_invalid_bitmap);
946 }
947restart:
948
949 if (ftl->unstable)
950 return -EIO;
951
952 /* If there are no spare blocks, */
953 /* we could still continue by erasing/writing the current block,
954 but for such worn out media it doesn't worth the trouble,
955 and the dangers */
956 if (kfifo_out(&zone->free_sectors,
957 (unsigned char *)&write_sector, 2) != 2) {
958 dbg("no free sectors for write!");
959 return -EIO;
960 }
961
962
963 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
964 ftl->cache_block, ftl->cache_data_invalid_bitmap))
965 goto restart;
966
967 /* Update the FTL table */
968 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
969
970 /* Write succesfull, so erase and free the old block */
971 if (block_num > 0)
972 sm_erase_block(ftl, zone_num, block_num, 1);
973
974 sm_cache_init(ftl);
975 return 0;
976}
977
978
979/* flush timer, runs a second after last write */
980static void sm_cache_flush_timer(struct timer_list *t)
981{
982 struct sm_ftl *ftl = from_timer(ftl, t, timer);
983 queue_work(cache_flush_workqueue, &ftl->flush_work);
984}
985
986/* cache flush work, kicked by timer */
987static void sm_cache_flush_work(struct work_struct *work)
988{
989 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
990 mutex_lock(&ftl->mutex);
991 sm_cache_flush(ftl);
992 mutex_unlock(&ftl->mutex);
993 return;
994}
995
996/* ---------------- outside interface -------------------------------------- */
997
998/* outside interface: read a sector */
999static int sm_read(struct mtd_blktrans_dev *dev,
1000 unsigned long sect_no, char *buf)
1001{
1002 struct sm_ftl *ftl = dev->priv;
1003 struct ftl_zone *zone;
1004 int error = 0, in_cache = 0;
1005 int zone_num, block, boffset;
1006
1007 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1008 mutex_lock(&ftl->mutex);
1009
1010
1011 zone = sm_get_zone(ftl, zone_num);
1012 if (IS_ERR(zone)) {
1013 error = PTR_ERR(zone);
1014 goto unlock;
1015 }
1016
1017 /* Have to look at cache first */
1018 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1019 in_cache = 1;
1020 if (!sm_cache_get(ftl, buf, boffset))
1021 goto unlock;
1022 }
1023
1024 /* Translate the block and return if doesn't exist in the table */
1025 block = zone->lba_to_phys_table[block];
1026
1027 if (block == -1) {
1028 memset(buf, 0xFF, SM_SECTOR_SIZE);
1029 goto unlock;
1030 }
1031
1032 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1033 error = -EIO;
1034 goto unlock;
1035 }
1036
1037 if (in_cache)
1038 sm_cache_put(ftl, buf, boffset);
1039unlock:
1040 mutex_unlock(&ftl->mutex);
1041 return error;
1042}
1043
1044/* outside interface: write a sector */
1045static int sm_write(struct mtd_blktrans_dev *dev,
1046 unsigned long sec_no, char *buf)
1047{
1048 struct sm_ftl *ftl = dev->priv;
1049 struct ftl_zone *zone;
1050 int error = 0, zone_num, block, boffset;
1051
1052 BUG_ON(ftl->readonly);
1053 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1054
1055 /* No need in flush thread running now */
1056 del_timer(&ftl->timer);
1057 mutex_lock(&ftl->mutex);
1058
1059 zone = sm_get_zone(ftl, zone_num);
1060 if (IS_ERR(zone)) {
1061 error = PTR_ERR(zone);
1062 goto unlock;
1063 }
1064
1065 /* If entry is not in cache, flush it */
1066 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1067
1068 error = sm_cache_flush(ftl);
1069 if (error)
1070 goto unlock;
1071
1072 ftl->cache_block = block;
1073 ftl->cache_zone = zone_num;
1074 }
1075
1076 sm_cache_put(ftl, buf, boffset);
1077unlock:
1078 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1079 mutex_unlock(&ftl->mutex);
1080 return error;
1081}
1082
1083/* outside interface: flush everything */
1084static int sm_flush(struct mtd_blktrans_dev *dev)
1085{
1086 struct sm_ftl *ftl = dev->priv;
1087 int retval;
1088
1089 mutex_lock(&ftl->mutex);
1090 retval = sm_cache_flush(ftl);
1091 mutex_unlock(&ftl->mutex);
1092 return retval;
1093}
1094
1095/* outside interface: device is released */
1096static void sm_release(struct mtd_blktrans_dev *dev)
1097{
1098 struct sm_ftl *ftl = dev->priv;
1099
1100 mutex_lock(&ftl->mutex);
1101 del_timer_sync(&ftl->timer);
1102 cancel_work_sync(&ftl->flush_work);
1103 sm_cache_flush(ftl);
1104 mutex_unlock(&ftl->mutex);
1105}
1106
1107/* outside interface: get geometry */
1108static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1109{
1110 struct sm_ftl *ftl = dev->priv;
1111 geo->heads = ftl->heads;
1112 geo->sectors = ftl->sectors;
1113 geo->cylinders = ftl->cylinders;
1114 return 0;
1115}
1116
1117/* external interface: main initialization function */
1118static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1119{
1120 struct mtd_blktrans_dev *trans;
1121 struct sm_ftl *ftl;
1122
1123 /* Allocate & initialize our private structure */
1124 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1125 if (!ftl)
1126 goto error1;
1127
1128
1129 mutex_init(&ftl->mutex);
1130 timer_setup(&ftl->timer, sm_cache_flush_timer, 0);
1131 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1132
1133 /* Read media information */
1134 if (sm_get_media_info(ftl, mtd)) {
1135 dbg("found unsupported mtd device, aborting");
1136 goto error2;
1137 }
1138
1139
1140 /* Allocate temporary CIS buffer for read retry support */
1141 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1142 if (!ftl->cis_buffer)
1143 goto error2;
1144
1145 /* Allocate zone array, it will be initialized on demand */
1146 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone),
1147 GFP_KERNEL);
1148 if (!ftl->zones)
1149 goto error3;
1150
1151 /* Allocate the cache*/
1152 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1153
1154 if (!ftl->cache_data)
1155 goto error4;
1156
1157 sm_cache_init(ftl);
1158
1159
1160 /* Allocate upper layer structure and initialize it */
1161 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1162 if (!trans)
1163 goto error5;
1164
1165 ftl->trans = trans;
1166 trans->priv = ftl;
1167
1168 trans->tr = tr;
1169 trans->mtd = mtd;
1170 trans->devnum = -1;
1171 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1172 trans->readonly = ftl->readonly;
1173
1174 if (sm_find_cis(ftl)) {
1175 dbg("CIS not found on mtd device, aborting");
1176 goto error6;
1177 }
1178
1179 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1180 if (!ftl->disk_attributes)
1181 goto error6;
1182 trans->disk_attributes = ftl->disk_attributes;
1183
1184 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1185 (int)(mtd->size / (1024 * 1024)), mtd->index);
1186
1187 dbg("FTL layout:");
1188 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1189 ftl->zone_count, ftl->max_lba,
1190 ftl->zone_size - ftl->max_lba);
1191 dbg("each block consists of %d bytes",
1192 ftl->block_size);
1193
1194
1195 /* Register device*/
1196 if (add_mtd_blktrans_dev(trans)) {
1197 dbg("error in mtdblktrans layer");
1198 goto error6;
1199 }
1200 return;
1201error6:
1202 kfree(trans);
1203error5:
1204 kfree(ftl->cache_data);
1205error4:
1206 kfree(ftl->zones);
1207error3:
1208 kfree(ftl->cis_buffer);
1209error2:
1210 kfree(ftl);
1211error1:
1212 return;
1213}
1214
1215/* main interface: device {surprise,} removal */
1216static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1217{
1218 struct sm_ftl *ftl = dev->priv;
1219 int i;
1220
1221 del_mtd_blktrans_dev(dev);
1222 ftl->trans = NULL;
1223
1224 for (i = 0 ; i < ftl->zone_count; i++) {
1225
1226 if (!ftl->zones[i].initialized)
1227 continue;
1228
1229 kfree(ftl->zones[i].lba_to_phys_table);
1230 kfifo_free(&ftl->zones[i].free_sectors);
1231 }
1232
1233 sm_delete_sysfs_attributes(ftl);
1234 kfree(ftl->cis_buffer);
1235 kfree(ftl->zones);
1236 kfree(ftl->cache_data);
1237 kfree(ftl);
1238}
1239
1240static struct mtd_blktrans_ops sm_ftl_ops = {
1241 .name = "smblk",
1242 .major = 0,
1243 .part_bits = SM_FTL_PARTN_BITS,
1244 .blksize = SM_SECTOR_SIZE,
1245 .getgeo = sm_getgeo,
1246
1247 .add_mtd = sm_add_mtd,
1248 .remove_dev = sm_remove_dev,
1249
1250 .readsect = sm_read,
1251 .writesect = sm_write,
1252
1253 .flush = sm_flush,
1254 .release = sm_release,
1255
1256 .owner = THIS_MODULE,
1257};
1258
1259static __init int sm_module_init(void)
1260{
1261 int error = 0;
1262
1263 cache_flush_workqueue = create_freezable_workqueue("smflush");
1264 if (!cache_flush_workqueue)
1265 return -ENOMEM;
1266
1267 error = register_mtd_blktrans(&sm_ftl_ops);
1268 if (error)
1269 destroy_workqueue(cache_flush_workqueue);
1270 return error;
1271
1272}
1273
1274static void __exit sm_module_exit(void)
1275{
1276 destroy_workqueue(cache_flush_workqueue);
1277 deregister_mtd_blktrans(&sm_ftl_ops);
1278}
1279
1280module_init(sm_module_init);
1281module_exit(sm_module_exit);
1282
1283MODULE_LICENSE("GPL");
1284MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1285MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");