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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.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");
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");