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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 if (buffer)
251 memset(buffer, 0xFF, SM_SECTOR_SIZE);
252 return 0;
253 }
254
255 /* User might not need the oob, but we do for data verification */
256 if (!oob)
257 oob = &tmp_oob;
258
259 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
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 /* Unfortunately, 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 && !mtd_is_bitflip_or_eccerr(ret)) {
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 (mtd_is_eccerr(ret) ||
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_OPS_RAW : MTD_OPS_PLACE_OOB;
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
350 if (ret) {
351 dbg("write to block %d at zone %d, failed with error %d",
352 block, zone, ret);
353
354 sm_recheck_media(ftl);
355 return ret;
356 }
357
358 /* This should never happen, unless there is a bug in the driver */
359 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
360 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
361
362 return 0;
363}
364
365/* ------------------------ block IO ------------------------------------- */
366
367/* Write a block using data and lba, and invalid sector bitmap */
368static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,
369 int zone, int block, int lba,
370 unsigned long invalid_bitmap)
371{
372 struct sm_oob oob;
373 int boffset;
374 int retry = 0;
375
376 /* Initialize the oob with requested values */
377 memset(&oob, 0xFF, SM_OOB_SIZE);
378 sm_write_lba(&oob, lba);
379restart:
380 if (ftl->unstable)
381 return -EIO;
382
383 for (boffset = 0; boffset < ftl->block_size;
384 boffset += SM_SECTOR_SIZE) {
385
386 oob.data_status = 0xFF;
387
388 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
389
390 sm_printk("sector %d of block at LBA %d of zone %d"
391 " couldn't be read, marking it as invalid",
392 boffset / SM_SECTOR_SIZE, lba, zone);
393
394 oob.data_status = 0;
395 }
396
397 if (ftl->smallpagenand) {
398 __nand_calculate_ecc(buf + boffset, SM_SMALL_PAGE,
399 oob.ecc1,
400 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
401
402 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE,
403 SM_SMALL_PAGE, oob.ecc2,
404 IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC));
405 }
406 if (!sm_write_sector(ftl, zone, block, boffset,
407 buf + boffset, &oob))
408 continue;
409
410 if (!retry) {
411
412 /* If write fails. try to erase the block */
413 /* This is safe, because we never write in blocks
414 that contain valuable data.
415 This is intended to repair block that are marked
416 as erased, but that isn't fully erased*/
417
418 if (sm_erase_block(ftl, zone, block, 0))
419 return -EIO;
420
421 retry = 1;
422 goto restart;
423 } else {
424 sm_mark_block_bad(ftl, zone, block);
425 return -EIO;
426 }
427 }
428 return 0;
429}
430
431
432/* Mark whole block at offset 'offs' as bad. */
433static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)
434{
435 struct sm_oob oob;
436 int boffset;
437
438 memset(&oob, 0xFF, SM_OOB_SIZE);
439 oob.block_status = 0xF0;
440
441 if (ftl->unstable)
442 return;
443
444 if (sm_recheck_media(ftl))
445 return;
446
447 sm_printk("marking block %d of zone %d as bad", block, zone);
448
449 /* We aren't checking the return value, because we don't care */
450 /* This also fails on fake xD cards, but I guess these won't expose
451 any bad blocks till fail completely */
452 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)
453 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);
454}
455
456/*
457 * Erase a block within a zone
458 * If erase succeeds, it updates free block fifo, otherwise marks block as bad
459 */
460static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
461 int put_free)
462{
463 struct ftl_zone *zone = &ftl->zones[zone_num];
464 struct mtd_info *mtd = ftl->trans->mtd;
465 struct erase_info erase;
466
467 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
468 erase.len = ftl->block_size;
469
470 if (ftl->unstable)
471 return -EIO;
472
473 BUG_ON(ftl->readonly);
474
475 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {
476 sm_printk("attempted to erase the CIS!");
477 return -EIO;
478 }
479
480 if (mtd_erase(mtd, &erase)) {
481 sm_printk("erase of block %d in zone %d failed",
482 block, zone_num);
483 goto error;
484 }
485
486 if (put_free)
487 kfifo_in(&zone->free_sectors,
488 (const unsigned char *)&block, sizeof(block));
489
490 return 0;
491error:
492 sm_mark_block_bad(ftl, zone_num, block);
493 return -EIO;
494}
495
496/* Thoroughly test that block is valid. */
497static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
498{
499 int boffset;
500 struct sm_oob oob;
501 int lbas[] = { -3, 0, 0, 0 };
502 int i = 0;
503 int test_lba;
504
505
506 /* First just check that block doesn't look fishy */
507 /* Only blocks that are valid or are sliced in two parts, are
508 accepted */
509 for (boffset = 0; boffset < ftl->block_size;
510 boffset += SM_SECTOR_SIZE) {
511
512 /* This shouldn't happen anyway */
513 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
514 return -2;
515
516 test_lba = sm_read_lba(&oob);
517
518 if (lbas[i] != test_lba)
519 lbas[++i] = test_lba;
520
521 /* If we found three different LBAs, something is fishy */
522 if (i == 3)
523 return -EIO;
524 }
525
526 /* If the block is sliced (partially erased usually) erase it */
527 if (i == 2) {
528 sm_erase_block(ftl, zone, block, 1);
529 return 1;
530 }
531
532 return 0;
533}
534
535/* ----------------- media scanning --------------------------------- */
536static const struct chs_entry chs_table[] = {
537 { 1, 125, 4, 4 },
538 { 2, 125, 4, 8 },
539 { 4, 250, 4, 8 },
540 { 8, 250, 4, 16 },
541 { 16, 500, 4, 16 },
542 { 32, 500, 8, 16 },
543 { 64, 500, 8, 32 },
544 { 128, 500, 16, 32 },
545 { 256, 1000, 16, 32 },
546 { 512, 1015, 32, 63 },
547 { 1024, 985, 33, 63 },
548 { 2048, 985, 33, 63 },
549 { 0 },
550};
551
552
553static const uint8_t cis_signature[] = {
554 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
555};
556/* Find out media parameters.
557 * This ideally has to be based on nand id, but for now device size is enough */
558static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
559{
560 int i;
561 int size_in_megs = mtd->size / (1024 * 1024);
562
563 ftl->readonly = mtd->type == MTD_ROM;
564
565 /* Manual settings for very old devices */
566 ftl->zone_count = 1;
567 ftl->smallpagenand = 0;
568
569 switch (size_in_megs) {
570 case 1:
571 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
572 ftl->zone_size = 256;
573 ftl->max_lba = 250;
574 ftl->block_size = 8 * SM_SECTOR_SIZE;
575 ftl->smallpagenand = 1;
576
577 break;
578 case 2:
579 /* 2 MiB flash SmartMedia (256 byte pages)*/
580 if (mtd->writesize == SM_SMALL_PAGE) {
581 ftl->zone_size = 512;
582 ftl->max_lba = 500;
583 ftl->block_size = 8 * SM_SECTOR_SIZE;
584 ftl->smallpagenand = 1;
585 /* 2 MiB rom SmartMedia */
586 } else {
587
588 if (!ftl->readonly)
589 return -ENODEV;
590
591 ftl->zone_size = 256;
592 ftl->max_lba = 250;
593 ftl->block_size = 16 * SM_SECTOR_SIZE;
594 }
595 break;
596 case 4:
597 /* 4 MiB flash/rom SmartMedia device */
598 ftl->zone_size = 512;
599 ftl->max_lba = 500;
600 ftl->block_size = 16 * SM_SECTOR_SIZE;
601 break;
602 case 8:
603 /* 8 MiB flash/rom SmartMedia device */
604 ftl->zone_size = 1024;
605 ftl->max_lba = 1000;
606 ftl->block_size = 16 * SM_SECTOR_SIZE;
607 }
608
609 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
610 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/
611 if (size_in_megs >= 16) {
612 ftl->zone_count = size_in_megs / 16;
613 ftl->zone_size = 1024;
614 ftl->max_lba = 1000;
615 ftl->block_size = 32 * SM_SECTOR_SIZE;
616 }
617
618 /* Test for proper write,erase and oob sizes */
619 if (mtd->erasesize > ftl->block_size)
620 return -ENODEV;
621
622 if (mtd->writesize > SM_SECTOR_SIZE)
623 return -ENODEV;
624
625 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
626 return -ENODEV;
627
628 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
629 return -ENODEV;
630
631 /* We use OOB */
632 if (!mtd_has_oob(mtd))
633 return -ENODEV;
634
635 /* Find geometry information */
636 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
637 if (chs_table[i].size == size_in_megs) {
638 ftl->cylinders = chs_table[i].cyl;
639 ftl->heads = chs_table[i].head;
640 ftl->sectors = chs_table[i].sec;
641 return 0;
642 }
643 }
644
645 sm_printk("media has unknown size : %dMiB", size_in_megs);
646 ftl->cylinders = 985;
647 ftl->heads = 33;
648 ftl->sectors = 63;
649 return 0;
650}
651
652/* Validate the CIS */
653static int sm_read_cis(struct sm_ftl *ftl)
654{
655 struct sm_oob oob;
656
657 if (sm_read_sector(ftl,
658 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
659 return -EIO;
660
661 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
662 return -EIO;
663
664 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
665 cis_signature, sizeof(cis_signature))) {
666 return 0;
667 }
668
669 return -EIO;
670}
671
672/* Scan the media for the CIS */
673static int sm_find_cis(struct sm_ftl *ftl)
674{
675 struct sm_oob oob;
676 int block, boffset;
677 int block_found = 0;
678 int cis_found = 0;
679
680 /* Search for first valid block */
681 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
682
683 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
684 continue;
685
686 if (!sm_block_valid(&oob))
687 continue;
688 block_found = 1;
689 break;
690 }
691
692 if (!block_found)
693 return -EIO;
694
695 /* Search for first valid sector in this block */
696 for (boffset = 0 ; boffset < ftl->block_size;
697 boffset += SM_SECTOR_SIZE) {
698
699 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
700 continue;
701
702 if (!sm_sector_valid(&oob))
703 continue;
704 break;
705 }
706
707 if (boffset == ftl->block_size)
708 return -EIO;
709
710 ftl->cis_block = block;
711 ftl->cis_boffset = boffset;
712 ftl->cis_page_offset = 0;
713
714 cis_found = !sm_read_cis(ftl);
715
716 if (!cis_found) {
717 ftl->cis_page_offset = SM_SMALL_PAGE;
718 cis_found = !sm_read_cis(ftl);
719 }
720
721 if (cis_found) {
722 dbg("CIS block found at offset %x",
723 block * ftl->block_size +
724 boffset + ftl->cis_page_offset);
725 return 0;
726 }
727 return -EIO;
728}
729
730/* Basic test to determine if underlying mtd device if functional */
731static int sm_recheck_media(struct sm_ftl *ftl)
732{
733 if (sm_read_cis(ftl)) {
734
735 if (!ftl->unstable) {
736 sm_printk("media unstable, not allowing writes");
737 ftl->unstable = 1;
738 }
739 return -EIO;
740 }
741 return 0;
742}
743
744/* Initialize a FTL zone */
745static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
746{
747 struct ftl_zone *zone = &ftl->zones[zone_num];
748 struct sm_oob oob;
749 uint16_t block;
750 int lba;
751 int i = 0;
752 int len;
753
754 dbg("initializing zone %d", zone_num);
755
756 /* Allocate memory for FTL table */
757 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL);
758
759 if (!zone->lba_to_phys_table)
760 return -ENOMEM;
761 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
762
763
764 /* Allocate memory for free sectors FIFO */
765 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
766 kfree(zone->lba_to_phys_table);
767 return -ENOMEM;
768 }
769
770 /* Now scan the zone */
771 for (block = 0 ; block < ftl->zone_size ; block++) {
772
773 /* Skip blocks till the CIS (including) */
774 if (zone_num == 0 && block <= ftl->cis_block)
775 continue;
776
777 /* Read the oob of first sector */
778 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob)) {
779 kfifo_free(&zone->free_sectors);
780 kfree(zone->lba_to_phys_table);
781 return -EIO;
782 }
783
784 /* Test to see if block is erased. It is enough to test
785 first sector, because erase happens in one shot */
786 if (sm_block_erased(&oob)) {
787 kfifo_in(&zone->free_sectors,
788 (unsigned char *)&block, 2);
789 continue;
790 }
791
792 /* If block is marked as bad, skip it */
793 /* This assumes we can trust first sector*/
794 /* However the way the block valid status is defined, ensures
795 very low probability of failure here */
796 if (!sm_block_valid(&oob)) {
797 dbg("PH %04d <-> <marked bad>", block);
798 continue;
799 }
800
801
802 lba = sm_read_lba(&oob);
803
804 /* Invalid LBA means that block is damaged. */
805 /* We can try to erase it, or mark it as bad, but
806 lets leave that to recovery application */
807 if (lba == -2 || lba >= ftl->max_lba) {
808 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
809 continue;
810 }
811
812
813 /* If there is no collision,
814 just put the sector in the FTL table */
815 if (zone->lba_to_phys_table[lba] < 0) {
816 dbg_verbose("PH %04d <-> LBA %04d", block, lba);
817 zone->lba_to_phys_table[lba] = block;
818 continue;
819 }
820
821 sm_printk("collision"
822 " of LBA %d between blocks %d and %d in zone %d",
823 lba, zone->lba_to_phys_table[lba], block, zone_num);
824
825 /* Test that this block is valid*/
826 if (sm_check_block(ftl, zone_num, block))
827 continue;
828
829 /* Test now the old block */
830 if (sm_check_block(ftl, zone_num,
831 zone->lba_to_phys_table[lba])) {
832 zone->lba_to_phys_table[lba] = block;
833 continue;
834 }
835
836 /* If both blocks are valid and share same LBA, it means that
837 they hold different versions of same data. It not
838 known which is more recent, thus just erase one of them
839 */
840 sm_printk("both blocks are valid, erasing the later");
841 sm_erase_block(ftl, zone_num, block, 1);
842 }
843
844 dbg("zone initialized");
845 zone->initialized = 1;
846
847 /* No free sectors, means that the zone is heavily damaged, write won't
848 work, but it can still can be (partially) read */
849 if (!kfifo_len(&zone->free_sectors)) {
850 sm_printk("no free blocks in zone %d", zone_num);
851 return 0;
852 }
853
854 /* Randomize first block we write to */
855 get_random_bytes(&i, 2);
856 i %= (kfifo_len(&zone->free_sectors) / 2);
857
858 while (i--) {
859 len = kfifo_out(&zone->free_sectors,
860 (unsigned char *)&block, 2);
861 WARN_ON(len != 2);
862 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
863 }
864 return 0;
865}
866
867/* Get and automatically initialize an FTL mapping for one zone */
868static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
869{
870 struct ftl_zone *zone;
871 int error;
872
873 BUG_ON(zone_num >= ftl->zone_count);
874 zone = &ftl->zones[zone_num];
875
876 if (!zone->initialized) {
877 error = sm_init_zone(ftl, zone_num);
878
879 if (error)
880 return ERR_PTR(error);
881 }
882 return zone;
883}
884
885
886/* ----------------- cache handling ------------------------------------------*/
887
888/* Initialize the one block cache */
889static void sm_cache_init(struct sm_ftl *ftl)
890{
891 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
892 ftl->cache_clean = 1;
893 ftl->cache_zone = -1;
894 ftl->cache_block = -1;
895 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
896}
897
898/* Put sector in one block cache */
899static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
900{
901 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
902 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
903 ftl->cache_clean = 0;
904}
905
906/* Read a sector from the cache */
907static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
908{
909 if (test_bit(boffset / SM_SECTOR_SIZE,
910 &ftl->cache_data_invalid_bitmap))
911 return -1;
912
913 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
914 return 0;
915}
916
917/* Write the cache to hardware */
918static int sm_cache_flush(struct sm_ftl *ftl)
919{
920 struct ftl_zone *zone;
921
922 int sector_num;
923 uint16_t write_sector;
924 int zone_num = ftl->cache_zone;
925 int block_num;
926
927 if (ftl->cache_clean)
928 return 0;
929
930 if (ftl->unstable)
931 return -EIO;
932
933 BUG_ON(zone_num < 0);
934 zone = &ftl->zones[zone_num];
935 block_num = zone->lba_to_phys_table[ftl->cache_block];
936
937
938 /* Try to read all unread areas of the cache block*/
939 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
940 ftl->block_size / SM_SECTOR_SIZE) {
941
942 if (!sm_read_sector(ftl,
943 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
944 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
945 clear_bit(sector_num,
946 &ftl->cache_data_invalid_bitmap);
947 }
948restart:
949
950 if (ftl->unstable)
951 return -EIO;
952
953 /* If there are no spare blocks, */
954 /* we could still continue by erasing/writing the current block,
955 but for such worn out media it doesn't worth the trouble,
956 and the dangers */
957 if (kfifo_out(&zone->free_sectors,
958 (unsigned char *)&write_sector, 2) != 2) {
959 dbg("no free sectors for write!");
960 return -EIO;
961 }
962
963
964 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
965 ftl->cache_block, ftl->cache_data_invalid_bitmap))
966 goto restart;
967
968 /* Update the FTL table */
969 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
970
971 /* Write succesfull, so erase and free the old block */
972 if (block_num > 0)
973 sm_erase_block(ftl, zone_num, block_num, 1);
974
975 sm_cache_init(ftl);
976 return 0;
977}
978
979
980/* flush timer, runs a second after last write */
981static void sm_cache_flush_timer(struct timer_list *t)
982{
983 struct sm_ftl *ftl = from_timer(ftl, t, timer);
984 queue_work(cache_flush_workqueue, &ftl->flush_work);
985}
986
987/* cache flush work, kicked by timer */
988static void sm_cache_flush_work(struct work_struct *work)
989{
990 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
991 mutex_lock(&ftl->mutex);
992 sm_cache_flush(ftl);
993 mutex_unlock(&ftl->mutex);
994 return;
995}
996
997/* ---------------- outside interface -------------------------------------- */
998
999/* outside interface: read a sector */
1000static int sm_read(struct mtd_blktrans_dev *dev,
1001 unsigned long sect_no, char *buf)
1002{
1003 struct sm_ftl *ftl = dev->priv;
1004 struct ftl_zone *zone;
1005 int error = 0, in_cache = 0;
1006 int zone_num, block, boffset;
1007
1008 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1009 mutex_lock(&ftl->mutex);
1010
1011
1012 zone = sm_get_zone(ftl, zone_num);
1013 if (IS_ERR(zone)) {
1014 error = PTR_ERR(zone);
1015 goto unlock;
1016 }
1017
1018 /* Have to look at cache first */
1019 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1020 in_cache = 1;
1021 if (!sm_cache_get(ftl, buf, boffset))
1022 goto unlock;
1023 }
1024
1025 /* Translate the block and return if doesn't exist in the table */
1026 block = zone->lba_to_phys_table[block];
1027
1028 if (block == -1) {
1029 memset(buf, 0xFF, SM_SECTOR_SIZE);
1030 goto unlock;
1031 }
1032
1033 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1034 error = -EIO;
1035 goto unlock;
1036 }
1037
1038 if (in_cache)
1039 sm_cache_put(ftl, buf, boffset);
1040unlock:
1041 mutex_unlock(&ftl->mutex);
1042 return error;
1043}
1044
1045/* outside interface: write a sector */
1046static int sm_write(struct mtd_blktrans_dev *dev,
1047 unsigned long sec_no, char *buf)
1048{
1049 struct sm_ftl *ftl = dev->priv;
1050 struct ftl_zone *zone;
1051 int error = 0, zone_num, block, boffset;
1052
1053 BUG_ON(ftl->readonly);
1054 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1055
1056 /* No need in flush thread running now */
1057 del_timer(&ftl->timer);
1058 mutex_lock(&ftl->mutex);
1059
1060 zone = sm_get_zone(ftl, zone_num);
1061 if (IS_ERR(zone)) {
1062 error = PTR_ERR(zone);
1063 goto unlock;
1064 }
1065
1066 /* If entry is not in cache, flush it */
1067 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1068
1069 error = sm_cache_flush(ftl);
1070 if (error)
1071 goto unlock;
1072
1073 ftl->cache_block = block;
1074 ftl->cache_zone = zone_num;
1075 }
1076
1077 sm_cache_put(ftl, buf, boffset);
1078unlock:
1079 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1080 mutex_unlock(&ftl->mutex);
1081 return error;
1082}
1083
1084/* outside interface: flush everything */
1085static int sm_flush(struct mtd_blktrans_dev *dev)
1086{
1087 struct sm_ftl *ftl = dev->priv;
1088 int retval;
1089
1090 mutex_lock(&ftl->mutex);
1091 retval = sm_cache_flush(ftl);
1092 mutex_unlock(&ftl->mutex);
1093 return retval;
1094}
1095
1096/* outside interface: device is released */
1097static void sm_release(struct mtd_blktrans_dev *dev)
1098{
1099 struct sm_ftl *ftl = dev->priv;
1100
1101 mutex_lock(&ftl->mutex);
1102 del_timer_sync(&ftl->timer);
1103 cancel_work_sync(&ftl->flush_work);
1104 sm_cache_flush(ftl);
1105 mutex_unlock(&ftl->mutex);
1106}
1107
1108/* outside interface: get geometry */
1109static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1110{
1111 struct sm_ftl *ftl = dev->priv;
1112 geo->heads = ftl->heads;
1113 geo->sectors = ftl->sectors;
1114 geo->cylinders = ftl->cylinders;
1115 return 0;
1116}
1117
1118/* external interface: main initialization function */
1119static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1120{
1121 struct mtd_blktrans_dev *trans;
1122 struct sm_ftl *ftl;
1123
1124 /* Allocate & initialize our private structure */
1125 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1126 if (!ftl)
1127 goto error1;
1128
1129
1130 mutex_init(&ftl->mutex);
1131 timer_setup(&ftl->timer, sm_cache_flush_timer, 0);
1132 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1133
1134 /* Read media information */
1135 if (sm_get_media_info(ftl, mtd)) {
1136 dbg("found unsupported mtd device, aborting");
1137 goto error2;
1138 }
1139
1140
1141 /* Allocate temporary CIS buffer for read retry support */
1142 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1143 if (!ftl->cis_buffer)
1144 goto error2;
1145
1146 /* Allocate zone array, it will be initialized on demand */
1147 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone),
1148 GFP_KERNEL);
1149 if (!ftl->zones)
1150 goto error3;
1151
1152 /* Allocate the cache*/
1153 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1154
1155 if (!ftl->cache_data)
1156 goto error4;
1157
1158 sm_cache_init(ftl);
1159
1160
1161 /* Allocate upper layer structure and initialize it */
1162 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1163 if (!trans)
1164 goto error5;
1165
1166 ftl->trans = trans;
1167 trans->priv = ftl;
1168
1169 trans->tr = tr;
1170 trans->mtd = mtd;
1171 trans->devnum = -1;
1172 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1173 trans->readonly = ftl->readonly;
1174
1175 if (sm_find_cis(ftl)) {
1176 dbg("CIS not found on mtd device, aborting");
1177 goto error6;
1178 }
1179
1180 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1181 if (!ftl->disk_attributes)
1182 goto error6;
1183 trans->disk_attributes = ftl->disk_attributes;
1184
1185 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1186 (int)(mtd->size / (1024 * 1024)), mtd->index);
1187
1188 dbg("FTL layout:");
1189 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1190 ftl->zone_count, ftl->max_lba,
1191 ftl->zone_size - ftl->max_lba);
1192 dbg("each block consists of %d bytes",
1193 ftl->block_size);
1194
1195
1196 /* Register device*/
1197 if (add_mtd_blktrans_dev(trans)) {
1198 dbg("error in mtdblktrans layer");
1199 goto error6;
1200 }
1201 return;
1202error6:
1203 kfree(trans);
1204error5:
1205 kfree(ftl->cache_data);
1206error4:
1207 kfree(ftl->zones);
1208error3:
1209 kfree(ftl->cis_buffer);
1210error2:
1211 kfree(ftl);
1212error1:
1213 return;
1214}
1215
1216/* main interface: device {surprise,} removal */
1217static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1218{
1219 struct sm_ftl *ftl = dev->priv;
1220 int i;
1221
1222 del_mtd_blktrans_dev(dev);
1223 ftl->trans = NULL;
1224
1225 for (i = 0 ; i < ftl->zone_count; i++) {
1226
1227 if (!ftl->zones[i].initialized)
1228 continue;
1229
1230 kfree(ftl->zones[i].lba_to_phys_table);
1231 kfifo_free(&ftl->zones[i].free_sectors);
1232 }
1233
1234 sm_delete_sysfs_attributes(ftl);
1235 kfree(ftl->cis_buffer);
1236 kfree(ftl->zones);
1237 kfree(ftl->cache_data);
1238 kfree(ftl);
1239}
1240
1241static struct mtd_blktrans_ops sm_ftl_ops = {
1242 .name = "smblk",
1243 .major = 0,
1244 .part_bits = SM_FTL_PARTN_BITS,
1245 .blksize = SM_SECTOR_SIZE,
1246 .getgeo = sm_getgeo,
1247
1248 .add_mtd = sm_add_mtd,
1249 .remove_dev = sm_remove_dev,
1250
1251 .readsect = sm_read,
1252 .writesect = sm_write,
1253
1254 .flush = sm_flush,
1255 .release = sm_release,
1256
1257 .owner = THIS_MODULE,
1258};
1259
1260static __init int sm_module_init(void)
1261{
1262 int error = 0;
1263
1264 cache_flush_workqueue = create_freezable_workqueue("smflush");
1265 if (!cache_flush_workqueue)
1266 return -ENOMEM;
1267
1268 error = register_mtd_blktrans(&sm_ftl_ops);
1269 if (error)
1270 destroy_workqueue(cache_flush_workqueue);
1271 return error;
1272
1273}
1274
1275static void __exit sm_module_exit(void)
1276{
1277 destroy_workqueue(cache_flush_workqueue);
1278 deregister_mtd_blktrans(&sm_ftl_ops);
1279}
1280
1281module_init(sm_module_init);
1282module_exit(sm_module_exit);
1283
1284MODULE_LICENSE("GPL");
1285MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1286MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");