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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-sw-hamming.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 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC);
220 uint8_t ecc[3];
221
222 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order);
223 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc1, SM_SMALL_PAGE,
224 sm_order) < 0)
225 return -EIO;
226
227 buffer += SM_SMALL_PAGE;
228
229 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order);
230 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc2, SM_SMALL_PAGE,
231 sm_order) < 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 if (buffer)
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 */
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 /* Unfortunately, oob read will _always_ succeed,
280 * despite card removal.....
281 */
282 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
283
284 /* Test for unknown errors */
285 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) {
286 dbg("read of block %d at zone %d, failed due to error (%d)",
287 block, zone, ret);
288 goto again;
289 }
290
291 /* Do a basic test on the oob, to guard against returned garbage */
292 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))
293 goto again;
294
295 /* This should never happen, unless there is a bug in the mtd driver */
296 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
297 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
298
299 if (!buffer)
300 return 0;
301
302 /* Test if sector marked as bad */
303 if (!sm_sector_valid(oob)) {
304 dbg("read of block %d at zone %d, failed because it is marked"
305 " as bad" , block, zone);
306 goto again;
307 }
308
309 /* Test ECC*/
310 if (mtd_is_eccerr(ret) ||
311 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {
312
313 dbg("read of block %d at zone %d, failed due to ECC error",
314 block, zone);
315 goto again;
316 }
317
318 return 0;
319}
320
321/* Writes a sector to media */
322static int sm_write_sector(struct sm_ftl *ftl,
323 int zone, int block, int boffset,
324 uint8_t *buffer, struct sm_oob *oob)
325{
326 struct mtd_oob_ops ops = { };
327 struct mtd_info *mtd = ftl->trans->mtd;
328 int ret;
329
330 BUG_ON(ftl->readonly);
331
332 if (zone == 0 && (block == ftl->cis_block || block == 0)) {
333 dbg("attempted to write the CIS!");
334 return -EIO;
335 }
336
337 if (ftl->unstable)
338 return -EIO;
339
340 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
341 ops.len = SM_SECTOR_SIZE;
342 ops.datbuf = buffer;
343 ops.ooboffs = 0;
344 ops.ooblen = SM_OOB_SIZE;
345 ops.oobbuf = (void *)oob;
346
347 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
348
349 /* Now we assume that hardware will catch write bitflip errors */
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 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC);
374 struct sm_oob oob;
375 int boffset;
376 int retry = 0;
377
378 /* Initialize the oob with requested values */
379 memset(&oob, 0xFF, SM_OOB_SIZE);
380 sm_write_lba(&oob, lba);
381restart:
382 if (ftl->unstable)
383 return -EIO;
384
385 for (boffset = 0; boffset < ftl->block_size;
386 boffset += SM_SECTOR_SIZE) {
387
388 oob.data_status = 0xFF;
389
390 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
391
392 sm_printk("sector %d of block at LBA %d of zone %d"
393 " couldn't be read, marking it as invalid",
394 boffset / SM_SECTOR_SIZE, lba, zone);
395
396 oob.data_status = 0;
397 }
398
399 if (ftl->smallpagenand) {
400 ecc_sw_hamming_calculate(buf + boffset,
401 SM_SMALL_PAGE, oob.ecc1,
402 sm_order);
403
404 ecc_sw_hamming_calculate(buf + boffset + SM_SMALL_PAGE,
405 SM_SMALL_PAGE, oob.ecc2,
406 sm_order);
407 }
408 if (!sm_write_sector(ftl, zone, block, boffset,
409 buf + boffset, &oob))
410 continue;
411
412 if (!retry) {
413
414 /* If write fails. try to erase the block */
415 /* This is safe, because we never write in blocks
416 * that contain valuable data.
417 * This is intended to repair block that are marked
418 * as erased, but that isn't fully erased
419 */
420
421 if (sm_erase_block(ftl, zone, block, 0))
422 return -EIO;
423
424 retry = 1;
425 goto restart;
426 } else {
427 sm_mark_block_bad(ftl, zone, block);
428 return -EIO;
429 }
430 }
431 return 0;
432}
433
434
435/* Mark whole block at offset 'offs' as bad. */
436static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)
437{
438 struct sm_oob oob;
439 int boffset;
440
441 memset(&oob, 0xFF, SM_OOB_SIZE);
442 oob.block_status = 0xF0;
443
444 if (ftl->unstable)
445 return;
446
447 if (sm_recheck_media(ftl))
448 return;
449
450 sm_printk("marking block %d of zone %d as bad", block, zone);
451
452 /* We aren't checking the return value, because we don't care */
453 /* This also fails on fake xD cards, but I guess these won't expose
454 * any bad blocks till fail completely
455 */
456 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)
457 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);
458}
459
460/*
461 * Erase a block within a zone
462 * If erase succeeds, it updates free block fifo, otherwise marks block as bad
463 */
464static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
465 int put_free)
466{
467 struct ftl_zone *zone = &ftl->zones[zone_num];
468 struct mtd_info *mtd = ftl->trans->mtd;
469 struct erase_info erase;
470
471 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
472 erase.len = ftl->block_size;
473
474 if (ftl->unstable)
475 return -EIO;
476
477 BUG_ON(ftl->readonly);
478
479 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {
480 sm_printk("attempted to erase the CIS!");
481 return -EIO;
482 }
483
484 if (mtd_erase(mtd, &erase)) {
485 sm_printk("erase of block %d in zone %d failed",
486 block, zone_num);
487 goto error;
488 }
489
490 if (put_free)
491 kfifo_in(&zone->free_sectors,
492 (const unsigned char *)&block, sizeof(block));
493
494 return 0;
495error:
496 sm_mark_block_bad(ftl, zone_num, block);
497 return -EIO;
498}
499
500/* Thoroughly test that block is valid. */
501static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
502{
503 int boffset;
504 struct sm_oob oob;
505 int lbas[] = { -3, 0, 0, 0 };
506 int i = 0;
507 int test_lba;
508
509
510 /* First just check that block doesn't look fishy */
511 /* Only blocks that are valid or are sliced in two parts, are
512 * accepted
513 */
514 for (boffset = 0; boffset < ftl->block_size;
515 boffset += SM_SECTOR_SIZE) {
516
517 /* This shouldn't happen anyway */
518 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
519 return -2;
520
521 test_lba = sm_read_lba(&oob);
522
523 if (lbas[i] != test_lba)
524 lbas[++i] = test_lba;
525
526 /* If we found three different LBAs, something is fishy */
527 if (i == 3)
528 return -EIO;
529 }
530
531 /* If the block is sliced (partially erased usually) erase it */
532 if (i == 2) {
533 sm_erase_block(ftl, zone, block, 1);
534 return 1;
535 }
536
537 return 0;
538}
539
540/* ----------------- media scanning --------------------------------- */
541static const struct chs_entry chs_table[] = {
542 { 1, 125, 4, 4 },
543 { 2, 125, 4, 8 },
544 { 4, 250, 4, 8 },
545 { 8, 250, 4, 16 },
546 { 16, 500, 4, 16 },
547 { 32, 500, 8, 16 },
548 { 64, 500, 8, 32 },
549 { 128, 500, 16, 32 },
550 { 256, 1000, 16, 32 },
551 { 512, 1015, 32, 63 },
552 { 1024, 985, 33, 63 },
553 { 2048, 985, 33, 63 },
554 { 0 },
555};
556
557
558static const uint8_t cis_signature[] = {
559 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
560};
561/* Find out media parameters.
562 * This ideally has to be based on nand id, but for now device size is enough
563 */
564static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
565{
566 int i;
567 int size_in_megs = mtd->size / (1024 * 1024);
568
569 ftl->readonly = mtd->type == MTD_ROM;
570
571 /* Manual settings for very old devices */
572 ftl->zone_count = 1;
573 ftl->smallpagenand = 0;
574
575 switch (size_in_megs) {
576 case 1:
577 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
578 ftl->zone_size = 256;
579 ftl->max_lba = 250;
580 ftl->block_size = 8 * SM_SECTOR_SIZE;
581 ftl->smallpagenand = 1;
582
583 break;
584 case 2:
585 /* 2 MiB flash SmartMedia (256 byte pages)*/
586 if (mtd->writesize == SM_SMALL_PAGE) {
587 ftl->zone_size = 512;
588 ftl->max_lba = 500;
589 ftl->block_size = 8 * SM_SECTOR_SIZE;
590 ftl->smallpagenand = 1;
591 /* 2 MiB rom SmartMedia */
592 } else {
593
594 if (!ftl->readonly)
595 return -ENODEV;
596
597 ftl->zone_size = 256;
598 ftl->max_lba = 250;
599 ftl->block_size = 16 * SM_SECTOR_SIZE;
600 }
601 break;
602 case 4:
603 /* 4 MiB flash/rom SmartMedia device */
604 ftl->zone_size = 512;
605 ftl->max_lba = 500;
606 ftl->block_size = 16 * SM_SECTOR_SIZE;
607 break;
608 case 8:
609 /* 8 MiB flash/rom SmartMedia device */
610 ftl->zone_size = 1024;
611 ftl->max_lba = 1000;
612 ftl->block_size = 16 * SM_SECTOR_SIZE;
613 }
614
615 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
616 * sizes. SmartMedia cards exist up to 128 MiB and have same layout
617 */
618 if (size_in_megs >= 16) {
619 ftl->zone_count = size_in_megs / 16;
620 ftl->zone_size = 1024;
621 ftl->max_lba = 1000;
622 ftl->block_size = 32 * SM_SECTOR_SIZE;
623 }
624
625 /* Test for proper write,erase and oob sizes */
626 if (mtd->erasesize > ftl->block_size)
627 return -ENODEV;
628
629 if (mtd->writesize > SM_SECTOR_SIZE)
630 return -ENODEV;
631
632 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
633 return -ENODEV;
634
635 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
636 return -ENODEV;
637
638 /* We use OOB */
639 if (!mtd_has_oob(mtd))
640 return -ENODEV;
641
642 /* Find geometry information */
643 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
644 if (chs_table[i].size == size_in_megs) {
645 ftl->cylinders = chs_table[i].cyl;
646 ftl->heads = chs_table[i].head;
647 ftl->sectors = chs_table[i].sec;
648 return 0;
649 }
650 }
651
652 sm_printk("media has unknown size : %dMiB", size_in_megs);
653 ftl->cylinders = 985;
654 ftl->heads = 33;
655 ftl->sectors = 63;
656 return 0;
657}
658
659/* Validate the CIS */
660static int sm_read_cis(struct sm_ftl *ftl)
661{
662 struct sm_oob oob;
663
664 if (sm_read_sector(ftl,
665 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
666 return -EIO;
667
668 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
669 return -EIO;
670
671 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
672 cis_signature, sizeof(cis_signature))) {
673 return 0;
674 }
675
676 return -EIO;
677}
678
679/* Scan the media for the CIS */
680static int sm_find_cis(struct sm_ftl *ftl)
681{
682 struct sm_oob oob;
683 int block, boffset;
684 int block_found = 0;
685 int cis_found = 0;
686
687 /* Search for first valid block */
688 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
689
690 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
691 continue;
692
693 if (!sm_block_valid(&oob))
694 continue;
695 block_found = 1;
696 break;
697 }
698
699 if (!block_found)
700 return -EIO;
701
702 /* Search for first valid sector in this block */
703 for (boffset = 0 ; boffset < ftl->block_size;
704 boffset += SM_SECTOR_SIZE) {
705
706 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
707 continue;
708
709 if (!sm_sector_valid(&oob))
710 continue;
711 break;
712 }
713
714 if (boffset == ftl->block_size)
715 return -EIO;
716
717 ftl->cis_block = block;
718 ftl->cis_boffset = boffset;
719 ftl->cis_page_offset = 0;
720
721 cis_found = !sm_read_cis(ftl);
722
723 if (!cis_found) {
724 ftl->cis_page_offset = SM_SMALL_PAGE;
725 cis_found = !sm_read_cis(ftl);
726 }
727
728 if (cis_found) {
729 dbg("CIS block found at offset %x",
730 block * ftl->block_size +
731 boffset + ftl->cis_page_offset);
732 return 0;
733 }
734 return -EIO;
735}
736
737/* Basic test to determine if underlying mtd device if functional */
738static int sm_recheck_media(struct sm_ftl *ftl)
739{
740 if (sm_read_cis(ftl)) {
741
742 if (!ftl->unstable) {
743 sm_printk("media unstable, not allowing writes");
744 ftl->unstable = 1;
745 }
746 return -EIO;
747 }
748 return 0;
749}
750
751/* Initialize a FTL zone */
752static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
753{
754 struct ftl_zone *zone = &ftl->zones[zone_num];
755 struct sm_oob oob;
756 uint16_t block;
757 int lba;
758 int i = 0;
759 int len;
760
761 dbg("initializing zone %d", zone_num);
762
763 /* Allocate memory for FTL table */
764 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL);
765
766 if (!zone->lba_to_phys_table)
767 return -ENOMEM;
768 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
769
770
771 /* Allocate memory for free sectors FIFO */
772 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
773 kfree(zone->lba_to_phys_table);
774 return -ENOMEM;
775 }
776
777 /* Now scan the zone */
778 for (block = 0 ; block < ftl->zone_size ; block++) {
779
780 /* Skip blocks till the CIS (including) */
781 if (zone_num == 0 && block <= ftl->cis_block)
782 continue;
783
784 /* Read the oob of first sector */
785 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) {
786 kfifo_free(&zone->free_sectors);
787 kfree(zone->lba_to_phys_table);
788 return -EIO;
789 }
790
791 /* Test to see if block is erased. It is enough to test
792 * first sector, because erase happens in one shot
793 */
794 if (sm_block_erased(&oob)) {
795 kfifo_in(&zone->free_sectors,
796 (unsigned char *)&block, 2);
797 continue;
798 }
799
800 /* If block is marked as bad, skip it */
801 /* This assumes we can trust first sector*/
802 /* However the way the block valid status is defined, ensures
803 * very low probability of failure here
804 */
805 if (!sm_block_valid(&oob)) {
806 dbg("PH %04d <-> <marked bad>", block);
807 continue;
808 }
809
810
811 lba = sm_read_lba(&oob);
812
813 /* Invalid LBA means that block is damaged. */
814 /* We can try to erase it, or mark it as bad, but
815 * lets leave that to recovery application
816 */
817 if (lba == -2 || lba >= ftl->max_lba) {
818 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
819 continue;
820 }
821
822
823 /* If there is no collision,
824 * just put the sector in the FTL table
825 */
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 */
861 if (!kfifo_len(&zone->free_sectors)) {
862 sm_printk("no free blocks in zone %d", zone_num);
863 return 0;
864 }
865
866 /* Randomize first block we write to */
867 get_random_bytes(&i, 2);
868 i %= (kfifo_len(&zone->free_sectors) / 2);
869
870 while (i--) {
871 len = kfifo_out(&zone->free_sectors,
872 (unsigned char *)&block, 2);
873 WARN_ON(len != 2);
874 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
875 }
876 return 0;
877}
878
879/* Get and automatically initialize an FTL mapping for one zone */
880static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
881{
882 struct ftl_zone *zone;
883 int error;
884
885 BUG_ON(zone_num >= ftl->zone_count);
886 zone = &ftl->zones[zone_num];
887
888 if (!zone->initialized) {
889 error = sm_init_zone(ftl, zone_num);
890
891 if (error)
892 return ERR_PTR(error);
893 }
894 return zone;
895}
896
897
898/* ----------------- cache handling ------------------------------------------*/
899
900/* Initialize the one block cache */
901static void sm_cache_init(struct sm_ftl *ftl)
902{
903 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
904 ftl->cache_clean = 1;
905 ftl->cache_zone = -1;
906 ftl->cache_block = -1;
907 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
908}
909
910/* Put sector in one block cache */
911static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
912{
913 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
914 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
915 ftl->cache_clean = 0;
916}
917
918/* Read a sector from the cache */
919static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
920{
921 if (test_bit(boffset / SM_SECTOR_SIZE,
922 &ftl->cache_data_invalid_bitmap))
923 return -1;
924
925 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
926 return 0;
927}
928
929/* Write the cache to hardware */
930static int sm_cache_flush(struct sm_ftl *ftl)
931{
932 struct ftl_zone *zone;
933
934 int sector_num;
935 uint16_t write_sector;
936 int zone_num = ftl->cache_zone;
937 int block_num;
938
939 if (ftl->cache_clean)
940 return 0;
941
942 if (ftl->unstable)
943 return -EIO;
944
945 BUG_ON(zone_num < 0);
946 zone = &ftl->zones[zone_num];
947 block_num = zone->lba_to_phys_table[ftl->cache_block];
948
949
950 /* Try to read all unread areas of the cache block*/
951 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
952 ftl->block_size / SM_SECTOR_SIZE) {
953
954 if (!sm_read_sector(ftl,
955 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
956 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
957 clear_bit(sector_num,
958 &ftl->cache_data_invalid_bitmap);
959 }
960restart:
961
962 if (ftl->unstable)
963 return -EIO;
964
965 /* If there are no spare blocks, */
966 /* we could still continue by erasing/writing the current block,
967 * but for such worn out media it doesn't worth the trouble,
968 * and the dangers
969 */
970 if (kfifo_out(&zone->free_sectors,
971 (unsigned char *)&write_sector, 2) != 2) {
972 dbg("no free sectors for write!");
973 return -EIO;
974 }
975
976
977 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
978 ftl->cache_block, ftl->cache_data_invalid_bitmap))
979 goto restart;
980
981 /* Update the FTL table */
982 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
983
984 /* Write successful, so erase and free the old block */
985 if (block_num > 0)
986 sm_erase_block(ftl, zone_num, block_num, 1);
987
988 sm_cache_init(ftl);
989 return 0;
990}
991
992
993/* flush timer, runs a second after last write */
994static void sm_cache_flush_timer(struct timer_list *t)
995{
996 struct sm_ftl *ftl = from_timer(ftl, t, timer);
997 queue_work(cache_flush_workqueue, &ftl->flush_work);
998}
999
1000/* cache flush work, kicked by timer */
1001static void sm_cache_flush_work(struct work_struct *work)
1002{
1003 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
1004 mutex_lock(&ftl->mutex);
1005 sm_cache_flush(ftl);
1006 mutex_unlock(&ftl->mutex);
1007 return;
1008}
1009
1010/* ---------------- outside interface -------------------------------------- */
1011
1012/* outside interface: read a sector */
1013static int sm_read(struct mtd_blktrans_dev *dev,
1014 unsigned long sect_no, char *buf)
1015{
1016 struct sm_ftl *ftl = dev->priv;
1017 struct ftl_zone *zone;
1018 int error = 0, in_cache = 0;
1019 int zone_num, block, boffset;
1020
1021 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1022 mutex_lock(&ftl->mutex);
1023
1024
1025 zone = sm_get_zone(ftl, zone_num);
1026 if (IS_ERR(zone)) {
1027 error = PTR_ERR(zone);
1028 goto unlock;
1029 }
1030
1031 /* Have to look at cache first */
1032 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1033 in_cache = 1;
1034 if (!sm_cache_get(ftl, buf, boffset))
1035 goto unlock;
1036 }
1037
1038 /* Translate the block and return if doesn't exist in the table */
1039 block = zone->lba_to_phys_table[block];
1040
1041 if (block == -1) {
1042 memset(buf, 0xFF, SM_SECTOR_SIZE);
1043 goto unlock;
1044 }
1045
1046 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1047 error = -EIO;
1048 goto unlock;
1049 }
1050
1051 if (in_cache)
1052 sm_cache_put(ftl, buf, boffset);
1053unlock:
1054 mutex_unlock(&ftl->mutex);
1055 return error;
1056}
1057
1058/* outside interface: write a sector */
1059static int sm_write(struct mtd_blktrans_dev *dev,
1060 unsigned long sec_no, char *buf)
1061{
1062 struct sm_ftl *ftl = dev->priv;
1063 struct ftl_zone *zone;
1064 int error = 0, zone_num, block, boffset;
1065
1066 BUG_ON(ftl->readonly);
1067 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1068
1069 /* No need in flush thread running now */
1070 del_timer(&ftl->timer);
1071 mutex_lock(&ftl->mutex);
1072
1073 zone = sm_get_zone(ftl, zone_num);
1074 if (IS_ERR(zone)) {
1075 error = PTR_ERR(zone);
1076 goto unlock;
1077 }
1078
1079 /* If entry is not in cache, flush it */
1080 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1081
1082 error = sm_cache_flush(ftl);
1083 if (error)
1084 goto unlock;
1085
1086 ftl->cache_block = block;
1087 ftl->cache_zone = zone_num;
1088 }
1089
1090 sm_cache_put(ftl, buf, boffset);
1091unlock:
1092 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1093 mutex_unlock(&ftl->mutex);
1094 return error;
1095}
1096
1097/* outside interface: flush everything */
1098static int sm_flush(struct mtd_blktrans_dev *dev)
1099{
1100 struct sm_ftl *ftl = dev->priv;
1101 int retval;
1102
1103 mutex_lock(&ftl->mutex);
1104 retval = sm_cache_flush(ftl);
1105 mutex_unlock(&ftl->mutex);
1106 return retval;
1107}
1108
1109/* outside interface: device is released */
1110static void sm_release(struct mtd_blktrans_dev *dev)
1111{
1112 struct sm_ftl *ftl = dev->priv;
1113
1114 del_timer_sync(&ftl->timer);
1115 cancel_work_sync(&ftl->flush_work);
1116 mutex_lock(&ftl->mutex);
1117 sm_cache_flush(ftl);
1118 mutex_unlock(&ftl->mutex);
1119}
1120
1121/* outside interface: get geometry */
1122static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1123{
1124 struct sm_ftl *ftl = dev->priv;
1125 geo->heads = ftl->heads;
1126 geo->sectors = ftl->sectors;
1127 geo->cylinders = ftl->cylinders;
1128 return 0;
1129}
1130
1131/* external interface: main initialization function */
1132static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1133{
1134 struct mtd_blktrans_dev *trans;
1135 struct sm_ftl *ftl;
1136
1137 /* Allocate & initialize our private structure */
1138 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1139 if (!ftl)
1140 goto error1;
1141
1142
1143 mutex_init(&ftl->mutex);
1144 timer_setup(&ftl->timer, sm_cache_flush_timer, 0);
1145 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1146
1147 /* Read media information */
1148 if (sm_get_media_info(ftl, mtd)) {
1149 dbg("found unsupported mtd device, aborting");
1150 goto error2;
1151 }
1152
1153
1154 /* Allocate temporary CIS buffer for read retry support */
1155 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1156 if (!ftl->cis_buffer)
1157 goto error2;
1158
1159 /* Allocate zone array, it will be initialized on demand */
1160 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone),
1161 GFP_KERNEL);
1162 if (!ftl->zones)
1163 goto error3;
1164
1165 /* Allocate the cache*/
1166 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1167
1168 if (!ftl->cache_data)
1169 goto error4;
1170
1171 sm_cache_init(ftl);
1172
1173
1174 /* Allocate upper layer structure and initialize it */
1175 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1176 if (!trans)
1177 goto error5;
1178
1179 ftl->trans = trans;
1180 trans->priv = ftl;
1181
1182 trans->tr = tr;
1183 trans->mtd = mtd;
1184 trans->devnum = -1;
1185 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1186 trans->readonly = ftl->readonly;
1187
1188 if (sm_find_cis(ftl)) {
1189 dbg("CIS not found on mtd device, aborting");
1190 goto error6;
1191 }
1192
1193 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1194 if (!ftl->disk_attributes)
1195 goto error6;
1196 trans->disk_attributes = ftl->disk_attributes;
1197
1198 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1199 (int)(mtd->size / (1024 * 1024)), mtd->index);
1200
1201 dbg("FTL layout:");
1202 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1203 ftl->zone_count, ftl->max_lba,
1204 ftl->zone_size - ftl->max_lba);
1205 dbg("each block consists of %d bytes",
1206 ftl->block_size);
1207
1208
1209 /* Register device*/
1210 if (add_mtd_blktrans_dev(trans)) {
1211 dbg("error in mtdblktrans layer");
1212 goto error6;
1213 }
1214 return;
1215error6:
1216 kfree(trans);
1217error5:
1218 kfree(ftl->cache_data);
1219error4:
1220 kfree(ftl->zones);
1221error3:
1222 kfree(ftl->cis_buffer);
1223error2:
1224 kfree(ftl);
1225error1:
1226 return;
1227}
1228
1229/* main interface: device {surprise,} removal */
1230static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1231{
1232 struct sm_ftl *ftl = dev->priv;
1233 int i;
1234
1235 del_mtd_blktrans_dev(dev);
1236 ftl->trans = NULL;
1237
1238 for (i = 0 ; i < ftl->zone_count; i++) {
1239
1240 if (!ftl->zones[i].initialized)
1241 continue;
1242
1243 kfree(ftl->zones[i].lba_to_phys_table);
1244 kfifo_free(&ftl->zones[i].free_sectors);
1245 }
1246
1247 sm_delete_sysfs_attributes(ftl);
1248 kfree(ftl->cis_buffer);
1249 kfree(ftl->zones);
1250 kfree(ftl->cache_data);
1251 kfree(ftl);
1252}
1253
1254static struct mtd_blktrans_ops sm_ftl_ops = {
1255 .name = "smblk",
1256 .major = 0,
1257 .part_bits = SM_FTL_PARTN_BITS,
1258 .blksize = SM_SECTOR_SIZE,
1259 .getgeo = sm_getgeo,
1260
1261 .add_mtd = sm_add_mtd,
1262 .remove_dev = sm_remove_dev,
1263
1264 .readsect = sm_read,
1265 .writesect = sm_write,
1266
1267 .flush = sm_flush,
1268 .release = sm_release,
1269
1270 .owner = THIS_MODULE,
1271};
1272
1273static __init int sm_module_init(void)
1274{
1275 int error = 0;
1276
1277 cache_flush_workqueue = create_freezable_workqueue("smflush");
1278 if (!cache_flush_workqueue)
1279 return -ENOMEM;
1280
1281 error = register_mtd_blktrans(&sm_ftl_ops);
1282 if (error)
1283 destroy_workqueue(cache_flush_workqueue);
1284 return error;
1285
1286}
1287
1288static void __exit sm_module_exit(void)
1289{
1290 destroy_workqueue(cache_flush_workqueue);
1291 deregister_mtd_blktrans(&sm_ftl_ops);
1292}
1293
1294module_init(sm_module_init);
1295module_exit(sm_module_exit);
1296
1297MODULE_LICENSE("GPL");
1298MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1299MODULE_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");