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Merge tag 'nios2-v4.19-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/lftan...
[linux/fpc-iii.git] / drivers / mtd / sm_ftl.c
blobf3bd86e136033d80e791fc996f0d9516d5e54d48
1 /*
2 * Copyright © 2009 - Maxim Levitsky
3 * SmartMedia/xD translation layer
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/random.h>
13 #include <linux/hdreg.h>
14 #include <linux/kthread.h>
15 #include <linux/freezer.h>
16 #include <linux/sysfs.h>
17 #include <linux/bitops.h>
18 #include <linux/slab.h>
19 #include <linux/mtd/nand_ecc.h>
20 #include "nand/raw/sm_common.h"
21 #include "sm_ftl.h"
22
23
24
25 static struct workqueue_struct *cache_flush_workqueue;
26
27 static int cache_timeout = 1000;
28 module_param(cache_timeout, int, S_IRUGO);
29 MODULE_PARM_DESC(cache_timeout,
30 "Timeout (in ms) for cache flush (1000 ms default");
31
32 static int debug;
33 module_param(debug, int, S_IRUGO | S_IWUSR);
34 MODULE_PARM_DESC(debug, "Debug level (0-2)");
35
36
37 /* ------------------- sysfs attributes ---------------------------------- */
38 struct sm_sysfs_attribute {
39 struct device_attribute dev_attr;
40 char *data;
41 int len;
42 };
43
44 static ssize_t sm_attr_show(struct device *dev, struct device_attribute *attr,
45 char *buf)
46 {
47 struct sm_sysfs_attribute *sm_attr =
48 container_of(attr, struct sm_sysfs_attribute, dev_attr);
49
50 strncpy(buf, sm_attr->data, sm_attr->len);
51 return sm_attr->len;
52 }
53
54
55 #define NUM_ATTRIBUTES 1
56 #define SM_CIS_VENDOR_OFFSET 0x59
57 static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl)
58 {
59 struct attribute_group *attr_group;
60 struct attribute **attributes;
61 struct sm_sysfs_attribute *vendor_attribute;
62 char *vendor;
63
64 vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET,
65 SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL);
66 if (!vendor)
67 goto error1;
68
69 /* Initialize sysfs attributes */
70 vendor_attribute =
71 kzalloc(sizeof(struct sm_sysfs_attribute), GFP_KERNEL);
72 if (!vendor_attribute)
73 goto error2;
74
75 sysfs_attr_init(&vendor_attribute->dev_attr.attr);
76
77 vendor_attribute->data = vendor;
78 vendor_attribute->len = strlen(vendor);
79 vendor_attribute->dev_attr.attr.name = "vendor";
80 vendor_attribute->dev_attr.attr.mode = S_IRUGO;
81 vendor_attribute->dev_attr.show = sm_attr_show;
82
83
84 /* Create array of pointers to the attributes */
85 attributes = kcalloc(NUM_ATTRIBUTES + 1, sizeof(struct attribute *),
86 GFP_KERNEL);
87 if (!attributes)
88 goto error3;
89 attributes[0] = &vendor_attribute->dev_attr.attr;
90
91 /* Finally create the attribute group */
92 attr_group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL);
93 if (!attr_group)
94 goto error4;
95 attr_group->attrs = attributes;
96 return attr_group;
97 error4:
98 kfree(attributes);
99 error3:
100 kfree(vendor_attribute);
101 error2:
102 kfree(vendor);
103 error1:
104 return NULL;
105 }
106
107 static void sm_delete_sysfs_attributes(struct sm_ftl *ftl)
108 {
109 struct attribute **attributes = ftl->disk_attributes->attrs;
110 int i;
111
112 for (i = 0; attributes[i] ; i++) {
113
114 struct device_attribute *dev_attr = container_of(attributes[i],
115 struct device_attribute, attr);
116
117 struct sm_sysfs_attribute *sm_attr =
118 container_of(dev_attr,
119 struct sm_sysfs_attribute, dev_attr);
120
121 kfree(sm_attr->data);
122 kfree(sm_attr);
123 }
124
125 kfree(ftl->disk_attributes->attrs);
126 kfree(ftl->disk_attributes);
127 }
128
129
130 /* ----------------------- oob helpers -------------------------------------- */
131
132 static int sm_get_lba(uint8_t *lba)
133 {
134 /* check fixed bits */
135 if ((lba[0] & 0xF8) != 0x10)
136 return -2;
137
138 /* check parity - endianness doesn't matter */
139 if (hweight16(*(uint16_t *)lba) & 1)
140 return -2;
141
142 return (lba[1] >> 1) | ((lba[0] & 0x07) << 7);
143 }
144
145
146 /*
147 * Read LBA associated with block
148 * returns -1, if block is erased
149 * returns -2 if error happens
150 */
151 static int sm_read_lba(struct sm_oob *oob)
152 {
153 static const uint32_t erased_pattern[4] = {
154 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };
155
156 uint16_t lba_test;
157 int lba;
158
159 /* First test for erased block */
160 if (!memcmp(oob, erased_pattern, SM_OOB_SIZE))
161 return -1;
162
163 /* Now check is both copies of the LBA differ too much */
164 lba_test = *(uint16_t *)oob->lba_copy1 ^ *(uint16_t*)oob->lba_copy2;
165 if (lba_test && !is_power_of_2(lba_test))
166 return -2;
167
168 /* And read it */
169 lba = sm_get_lba(oob->lba_copy1);
170
171 if (lba == -2)
172 lba = sm_get_lba(oob->lba_copy2);
173
174 return lba;
175 }
176
177 static void sm_write_lba(struct sm_oob *oob, uint16_t lba)
178 {
179 uint8_t tmp[2];
180
181 WARN_ON(lba >= 1000);
182
183 tmp[0] = 0x10 | ((lba >> 7) & 0x07);
184 tmp[1] = (lba << 1) & 0xFF;
185
186 if (hweight16(*(uint16_t *)tmp) & 0x01)
187 tmp[1] |= 1;
188
189 oob->lba_copy1[0] = oob->lba_copy2[0] = tmp[0];
190 oob->lba_copy1[1] = oob->lba_copy2[1] = tmp[1];
191 }
192
193
194 /* Make offset from parts */
195 static loff_t sm_mkoffset(struct sm_ftl *ftl, int zone, int block, int boffset)
196 {
197 WARN_ON(boffset & (SM_SECTOR_SIZE - 1));
198 WARN_ON(zone < 0 || zone >= ftl->zone_count);
199 WARN_ON(block >= ftl->zone_size);
200 WARN_ON(boffset >= ftl->block_size);
201
202 if (block == -1)
203 return -1;
204
205 return (zone * SM_MAX_ZONE_SIZE + block) * ftl->block_size + boffset;
206 }
207
208 /* Breaks offset into parts */
209 static void sm_break_offset(struct sm_ftl *ftl, loff_t loffset,
210 int *zone, int *block, int *boffset)
211 {
212 u64 offset = loffset;
213 *boffset = do_div(offset, ftl->block_size);
214 *block = do_div(offset, ftl->max_lba);
215 *zone = offset >= ftl->zone_count ? -1 : offset;
216 }
217
218 /* ---------------------- low level IO ------------------------------------- */
219
220 static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob)
221 {
222 uint8_t ecc[3];
223
224 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
225 if (__nand_correct_data(buffer, ecc, oob->ecc1, SM_SMALL_PAGE) < 0)
226 return -EIO;
227
228 buffer += SM_SMALL_PAGE;
229
230 __nand_calculate_ecc(buffer, SM_SMALL_PAGE, ecc);
231 if (__nand_correct_data(buffer, ecc, oob->ecc2, SM_SMALL_PAGE) < 0)
232 return -EIO;
233 return 0;
234 }
235
236 /* Reads a sector + oob*/
237 static int sm_read_sector(struct sm_ftl *ftl,
238 int zone, int block, int boffset,
239 uint8_t *buffer, struct sm_oob *oob)
240 {
241 struct mtd_info *mtd = ftl->trans->mtd;
242 struct mtd_oob_ops ops;
243 struct sm_oob tmp_oob;
244 int ret = -EIO;
245 int try = 0;
246
247 /* FTL can contain -1 entries that are by default filled with bits */
248 if (block == -1) {
249 memset(buffer, 0xFF, SM_SECTOR_SIZE);
250 return 0;
251 }
252
253 /* User might not need the oob, but we do for data verification */
254 if (!oob)
255 oob = &tmp_oob;
256
257 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
258 ops.ooboffs = 0;
259 ops.ooblen = SM_OOB_SIZE;
260 ops.oobbuf = (void *)oob;
261 ops.len = SM_SECTOR_SIZE;
262 ops.datbuf = buffer;
263
264 again:
265 if (try++) {
266 /* Avoid infinite recursion on CIS reads, sm_recheck_media
267 won't help anyway */
268 if (zone == 0 && block == ftl->cis_block && boffset ==
269 ftl->cis_boffset)
270 return ret;
271
272 /* Test if media is stable */
273 if (try == 3 || sm_recheck_media(ftl))
274 return ret;
275 }
276
277 /* Unfortunately, oob read will _always_ succeed,
278 despite card removal..... */
279 ret = mtd_read_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
280
281 /* Test for unknown errors */
282 if (ret != 0 && !mtd_is_bitflip_or_eccerr(ret)) {
283 dbg("read of block %d at zone %d, failed due to error (%d)",
284 block, zone, ret);
285 goto again;
286 }
287
288 /* Do a basic test on the oob, to guard against returned garbage */
289 if (oob->reserved != 0xFFFFFFFF && !is_power_of_2(~oob->reserved))
290 goto again;
291
292 /* This should never happen, unless there is a bug in the mtd driver */
293 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
294 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
295
296 if (!buffer)
297 return 0;
298
299 /* Test if sector marked as bad */
300 if (!sm_sector_valid(oob)) {
301 dbg("read of block %d at zone %d, failed because it is marked"
302 " as bad" , block, zone);
303 goto again;
304 }
305
306 /* Test ECC*/
307 if (mtd_is_eccerr(ret) ||
308 (ftl->smallpagenand && sm_correct_sector(buffer, oob))) {
309
310 dbg("read of block %d at zone %d, failed due to ECC error",
311 block, zone);
312 goto again;
313 }
314
315 return 0;
316 }
317
318 /* Writes a sector to media */
319 static int sm_write_sector(struct sm_ftl *ftl,
320 int zone, int block, int boffset,
321 uint8_t *buffer, struct sm_oob *oob)
322 {
323 struct mtd_oob_ops ops;
324 struct mtd_info *mtd = ftl->trans->mtd;
325 int ret;
326
327 BUG_ON(ftl->readonly);
328
329 if (zone == 0 && (block == ftl->cis_block || block == 0)) {
330 dbg("attempted to write the CIS!");
331 return -EIO;
332 }
333
334 if (ftl->unstable)
335 return -EIO;
336
337 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
338 ops.len = SM_SECTOR_SIZE;
339 ops.datbuf = buffer;
340 ops.ooboffs = 0;
341 ops.ooblen = SM_OOB_SIZE;
342 ops.oobbuf = (void *)oob;
343
344 ret = mtd_write_oob(mtd, sm_mkoffset(ftl, zone, block, boffset), &ops);
345
346 /* Now we assume that hardware will catch write bitflip errors */
347
348 if (ret) {
349 dbg("write to block %d at zone %d, failed with error %d",
350 block, zone, ret);
351
352 sm_recheck_media(ftl);
353 return ret;
354 }
355
356 /* This should never happen, unless there is a bug in the driver */
357 WARN_ON(ops.oobretlen != SM_OOB_SIZE);
358 WARN_ON(buffer && ops.retlen != SM_SECTOR_SIZE);
359
360 return 0;
361 }
362
363 /* ------------------------ block IO ------------------------------------- */
364
365 /* Write a block using data and lba, and invalid sector bitmap */
366 static int sm_write_block(struct sm_ftl *ftl, uint8_t *buf,
367 int zone, int block, int lba,
368 unsigned long invalid_bitmap)
369 {
370 struct sm_oob oob;
371 int boffset;
372 int retry = 0;
373
374 /* Initialize the oob with requested values */
375 memset(&oob, 0xFF, SM_OOB_SIZE);
376 sm_write_lba(&oob, lba);
377 restart:
378 if (ftl->unstable)
379 return -EIO;
380
381 for (boffset = 0; boffset < ftl->block_size;
382 boffset += SM_SECTOR_SIZE) {
383
384 oob.data_status = 0xFF;
385
386 if (test_bit(boffset / SM_SECTOR_SIZE, &invalid_bitmap)) {
387
388 sm_printk("sector %d of block at LBA %d of zone %d"
389 " couldn't be read, marking it as invalid",
390 boffset / SM_SECTOR_SIZE, lba, zone);
391
392 oob.data_status = 0;
393 }
394
395 if (ftl->smallpagenand) {
396 __nand_calculate_ecc(buf + boffset,
397 SM_SMALL_PAGE, oob.ecc1);
398
399 __nand_calculate_ecc(buf + boffset + SM_SMALL_PAGE,
400 SM_SMALL_PAGE, oob.ecc2);
401 }
402 if (!sm_write_sector(ftl, zone, block, boffset,
403 buf + boffset, &oob))
404 continue;
405
406 if (!retry) {
407
408 /* If write fails. try to erase the block */
409 /* This is safe, because we never write in blocks
410 that contain valuable data.
411 This is intended to repair block that are marked
412 as erased, but that isn't fully erased*/
413
414 if (sm_erase_block(ftl, zone, block, 0))
415 return -EIO;
416
417 retry = 1;
418 goto restart;
419 } else {
420 sm_mark_block_bad(ftl, zone, block);
421 return -EIO;
422 }
423 }
424 return 0;
425 }
426
427
428 /* Mark whole block at offset 'offs' as bad. */
429 static void sm_mark_block_bad(struct sm_ftl *ftl, int zone, int block)
430 {
431 struct sm_oob oob;
432 int boffset;
433
434 memset(&oob, 0xFF, SM_OOB_SIZE);
435 oob.block_status = 0xF0;
436
437 if (ftl->unstable)
438 return;
439
440 if (sm_recheck_media(ftl))
441 return;
442
443 sm_printk("marking block %d of zone %d as bad", block, zone);
444
445 /* We aren't checking the return value, because we don't care */
446 /* This also fails on fake xD cards, but I guess these won't expose
447 any bad blocks till fail completely */
448 for (boffset = 0; boffset < ftl->block_size; boffset += SM_SECTOR_SIZE)
449 sm_write_sector(ftl, zone, block, boffset, NULL, &oob);
450 }
451
452 /*
453 * Erase a block within a zone
454 * If erase succeeds, it updates free block fifo, otherwise marks block as bad
455 */
456 static int sm_erase_block(struct sm_ftl *ftl, int zone_num, uint16_t block,
457 int put_free)
458 {
459 struct ftl_zone *zone = &ftl->zones[zone_num];
460 struct mtd_info *mtd = ftl->trans->mtd;
461 struct erase_info erase;
462
463 erase.addr = sm_mkoffset(ftl, zone_num, block, 0);
464 erase.len = ftl->block_size;
465
466 if (ftl->unstable)
467 return -EIO;
468
469 BUG_ON(ftl->readonly);
470
471 if (zone_num == 0 && (block == ftl->cis_block || block == 0)) {
472 sm_printk("attempted to erase the CIS!");
473 return -EIO;
474 }
475
476 if (mtd_erase(mtd, &erase)) {
477 sm_printk("erase of block %d in zone %d failed",
478 block, zone_num);
479 goto error;
480 }
481
482 if (put_free)
483 kfifo_in(&zone->free_sectors,
484 (const unsigned char *)&block, sizeof(block));
485
486 return 0;
487 error:
488 sm_mark_block_bad(ftl, zone_num, block);
489 return -EIO;
490 }
491
492 /* Thoroughly test that block is valid. */
493 static int sm_check_block(struct sm_ftl *ftl, int zone, int block)
494 {
495 int boffset;
496 struct sm_oob oob;
497 int lbas[] = { -3, 0, 0, 0 };
498 int i = 0;
499 int test_lba;
500
501
502 /* First just check that block doesn't look fishy */
503 /* Only blocks that are valid or are sliced in two parts, are
504 accepted */
505 for (boffset = 0; boffset < ftl->block_size;
506 boffset += SM_SECTOR_SIZE) {
507
508 /* This shouldn't happen anyway */
509 if (sm_read_sector(ftl, zone, block, boffset, NULL, &oob))
510 return -2;
511
512 test_lba = sm_read_lba(&oob);
513
514 if (lbas[i] != test_lba)
515 lbas[++i] = test_lba;
516
517 /* If we found three different LBAs, something is fishy */
518 if (i == 3)
519 return -EIO;
520 }
521
522 /* If the block is sliced (partially erased usually) erase it */
523 if (i == 2) {
524 sm_erase_block(ftl, zone, block, 1);
525 return 1;
526 }
527
528 return 0;
529 }
530
531 /* ----------------- media scanning --------------------------------- */
532 static const struct chs_entry chs_table[] = {
533 { 1, 125, 4, 4 },
534 { 2, 125, 4, 8 },
535 { 4, 250, 4, 8 },
536 { 8, 250, 4, 16 },
537 { 16, 500, 4, 16 },
538 { 32, 500, 8, 16 },
539 { 64, 500, 8, 32 },
540 { 128, 500, 16, 32 },
541 { 256, 1000, 16, 32 },
542 { 512, 1015, 32, 63 },
543 { 1024, 985, 33, 63 },
544 { 2048, 985, 33, 63 },
545 { 0 },
546 };
547
548
549 static const uint8_t cis_signature[] = {
550 0x01, 0x03, 0xD9, 0x01, 0xFF, 0x18, 0x02, 0xDF, 0x01, 0x20
551 };
552 /* Find out media parameters.
553 * This ideally has to be based on nand id, but for now device size is enough */
554 static int sm_get_media_info(struct sm_ftl *ftl, struct mtd_info *mtd)
555 {
556 int i;
557 int size_in_megs = mtd->size / (1024 * 1024);
558
559 ftl->readonly = mtd->type == MTD_ROM;
560
561 /* Manual settings for very old devices */
562 ftl->zone_count = 1;
563 ftl->smallpagenand = 0;
564
565 switch (size_in_megs) {
566 case 1:
567 /* 1 MiB flash/rom SmartMedia card (256 byte pages)*/
568 ftl->zone_size = 256;
569 ftl->max_lba = 250;
570 ftl->block_size = 8 * SM_SECTOR_SIZE;
571 ftl->smallpagenand = 1;
572
573 break;
574 case 2:
575 /* 2 MiB flash SmartMedia (256 byte pages)*/
576 if (mtd->writesize == SM_SMALL_PAGE) {
577 ftl->zone_size = 512;
578 ftl->max_lba = 500;
579 ftl->block_size = 8 * SM_SECTOR_SIZE;
580 ftl->smallpagenand = 1;
581 /* 2 MiB rom SmartMedia */
582 } else {
583
584 if (!ftl->readonly)
585 return -ENODEV;
586
587 ftl->zone_size = 256;
588 ftl->max_lba = 250;
589 ftl->block_size = 16 * SM_SECTOR_SIZE;
590 }
591 break;
592 case 4:
593 /* 4 MiB flash/rom SmartMedia device */
594 ftl->zone_size = 512;
595 ftl->max_lba = 500;
596 ftl->block_size = 16 * SM_SECTOR_SIZE;
597 break;
598 case 8:
599 /* 8 MiB flash/rom SmartMedia device */
600 ftl->zone_size = 1024;
601 ftl->max_lba = 1000;
602 ftl->block_size = 16 * SM_SECTOR_SIZE;
603 }
604
605 /* Minimum xD size is 16MiB. Also, all xD cards have standard zone
606 sizes. SmartMedia cards exist up to 128 MiB and have same layout*/
607 if (size_in_megs >= 16) {
608 ftl->zone_count = size_in_megs / 16;
609 ftl->zone_size = 1024;
610 ftl->max_lba = 1000;
611 ftl->block_size = 32 * SM_SECTOR_SIZE;
612 }
613
614 /* Test for proper write,erase and oob sizes */
615 if (mtd->erasesize > ftl->block_size)
616 return -ENODEV;
617
618 if (mtd->writesize > SM_SECTOR_SIZE)
619 return -ENODEV;
620
621 if (ftl->smallpagenand && mtd->oobsize < SM_SMALL_OOB_SIZE)
622 return -ENODEV;
623
624 if (!ftl->smallpagenand && mtd->oobsize < SM_OOB_SIZE)
625 return -ENODEV;
626
627 /* We use OOB */
628 if (!mtd_has_oob(mtd))
629 return -ENODEV;
630
631 /* Find geometry information */
632 for (i = 0 ; i < ARRAY_SIZE(chs_table) ; i++) {
633 if (chs_table[i].size == size_in_megs) {
634 ftl->cylinders = chs_table[i].cyl;
635 ftl->heads = chs_table[i].head;
636 ftl->sectors = chs_table[i].sec;
637 return 0;
638 }
639 }
640
641 sm_printk("media has unknown size : %dMiB", size_in_megs);
642 ftl->cylinders = 985;
643 ftl->heads = 33;
644 ftl->sectors = 63;
645 return 0;
646 }
647
648 /* Validate the CIS */
649 static int sm_read_cis(struct sm_ftl *ftl)
650 {
651 struct sm_oob oob;
652
653 if (sm_read_sector(ftl,
654 0, ftl->cis_block, ftl->cis_boffset, ftl->cis_buffer, &oob))
655 return -EIO;
656
657 if (!sm_sector_valid(&oob) || !sm_block_valid(&oob))
658 return -EIO;
659
660 if (!memcmp(ftl->cis_buffer + ftl->cis_page_offset,
661 cis_signature, sizeof(cis_signature))) {
662 return 0;
663 }
664
665 return -EIO;
666 }
667
668 /* Scan the media for the CIS */
669 static int sm_find_cis(struct sm_ftl *ftl)
670 {
671 struct sm_oob oob;
672 int block, boffset;
673 int block_found = 0;
674 int cis_found = 0;
675
676 /* Search for first valid block */
677 for (block = 0 ; block < ftl->zone_size - ftl->max_lba ; block++) {
678
679 if (sm_read_sector(ftl, 0, block, 0, NULL, &oob))
680 continue;
681
682 if (!sm_block_valid(&oob))
683 continue;
684 block_found = 1;
685 break;
686 }
687
688 if (!block_found)
689 return -EIO;
690
691 /* Search for first valid sector in this block */
692 for (boffset = 0 ; boffset < ftl->block_size;
693 boffset += SM_SECTOR_SIZE) {
694
695 if (sm_read_sector(ftl, 0, block, boffset, NULL, &oob))
696 continue;
697
698 if (!sm_sector_valid(&oob))
699 continue;
700 break;
701 }
702
703 if (boffset == ftl->block_size)
704 return -EIO;
705
706 ftl->cis_block = block;
707 ftl->cis_boffset = boffset;
708 ftl->cis_page_offset = 0;
709
710 cis_found = !sm_read_cis(ftl);
711
712 if (!cis_found) {
713 ftl->cis_page_offset = SM_SMALL_PAGE;
714 cis_found = !sm_read_cis(ftl);
715 }
716
717 if (cis_found) {
718 dbg("CIS block found at offset %x",
719 block * ftl->block_size +
720 boffset + ftl->cis_page_offset);
721 return 0;
722 }
723 return -EIO;
724 }
725
726 /* Basic test to determine if underlying mtd device if functional */
727 static int sm_recheck_media(struct sm_ftl *ftl)
728 {
729 if (sm_read_cis(ftl)) {
730
731 if (!ftl->unstable) {
732 sm_printk("media unstable, not allowing writes");
733 ftl->unstable = 1;
734 }
735 return -EIO;
736 }
737 return 0;
738 }
739
740 /* Initialize a FTL zone */
741 static int sm_init_zone(struct sm_ftl *ftl, int zone_num)
742 {
743 struct ftl_zone *zone = &ftl->zones[zone_num];
744 struct sm_oob oob;
745 uint16_t block;
746 int lba;
747 int i = 0;
748 int len;
749
750 dbg("initializing zone %d", zone_num);
751
752 /* Allocate memory for FTL table */
753 zone->lba_to_phys_table = kmalloc_array(ftl->max_lba, 2, GFP_KERNEL);
754
755 if (!zone->lba_to_phys_table)
756 return -ENOMEM;
757 memset(zone->lba_to_phys_table, -1, ftl->max_lba * 2);
758
759
760 /* Allocate memory for free sectors FIFO */
761 if (kfifo_alloc(&zone->free_sectors, ftl->zone_size * 2, GFP_KERNEL)) {
762 kfree(zone->lba_to_phys_table);
763 return -ENOMEM;
764 }
765
766 /* Now scan the zone */
767 for (block = 0 ; block < ftl->zone_size ; block++) {
768
769 /* Skip blocks till the CIS (including) */
770 if (zone_num == 0 && block <= ftl->cis_block)
771 continue;
772
773 /* Read the oob of first sector */
774 if (sm_read_sector(ftl, zone_num, block, 0, NULL, &oob))
775 return -EIO;
776
777 /* Test to see if block is erased. It is enough to test
778 first sector, because erase happens in one shot */
779 if (sm_block_erased(&oob)) {
780 kfifo_in(&zone->free_sectors,
781 (unsigned char *)&block, 2);
782 continue;
783 }
784
785 /* If block is marked as bad, skip it */
786 /* This assumes we can trust first sector*/
787 /* However the way the block valid status is defined, ensures
788 very low probability of failure here */
789 if (!sm_block_valid(&oob)) {
790 dbg("PH %04d <-> <marked bad>", block);
791 continue;
792 }
793
794
795 lba = sm_read_lba(&oob);
796
797 /* Invalid LBA means that block is damaged. */
798 /* We can try to erase it, or mark it as bad, but
799 lets leave that to recovery application */
800 if (lba == -2 || lba >= ftl->max_lba) {
801 dbg("PH %04d <-> LBA %04d(bad)", block, lba);
802 continue;
803 }
804
805
806 /* If there is no collision,
807 just put the sector in the FTL table */
808 if (zone->lba_to_phys_table[lba] < 0) {
809 dbg_verbose("PH %04d <-> LBA %04d", block, lba);
810 zone->lba_to_phys_table[lba] = block;
811 continue;
812 }
813
814 sm_printk("collision"
815 " of LBA %d between blocks %d and %d in zone %d",
816 lba, zone->lba_to_phys_table[lba], block, zone_num);
817
818 /* Test that this block is valid*/
819 if (sm_check_block(ftl, zone_num, block))
820 continue;
821
822 /* Test now the old block */
823 if (sm_check_block(ftl, zone_num,
824 zone->lba_to_phys_table[lba])) {
825 zone->lba_to_phys_table[lba] = block;
826 continue;
827 }
828
829 /* If both blocks are valid and share same LBA, it means that
830 they hold different versions of same data. It not
831 known which is more recent, thus just erase one of them
832 */
833 sm_printk("both blocks are valid, erasing the later");
834 sm_erase_block(ftl, zone_num, block, 1);
835 }
836
837 dbg("zone initialized");
838 zone->initialized = 1;
839
840 /* No free sectors, means that the zone is heavily damaged, write won't
841 work, but it can still can be (partially) read */
842 if (!kfifo_len(&zone->free_sectors)) {
843 sm_printk("no free blocks in zone %d", zone_num);
844 return 0;
845 }
846
847 /* Randomize first block we write to */
848 get_random_bytes(&i, 2);
849 i %= (kfifo_len(&zone->free_sectors) / 2);
850
851 while (i--) {
852 len = kfifo_out(&zone->free_sectors,
853 (unsigned char *)&block, 2);
854 WARN_ON(len != 2);
855 kfifo_in(&zone->free_sectors, (const unsigned char *)&block, 2);
856 }
857 return 0;
858 }
859
860 /* Get and automatically initialize an FTL mapping for one zone */
861 static struct ftl_zone *sm_get_zone(struct sm_ftl *ftl, int zone_num)
862 {
863 struct ftl_zone *zone;
864 int error;
865
866 BUG_ON(zone_num >= ftl->zone_count);
867 zone = &ftl->zones[zone_num];
868
869 if (!zone->initialized) {
870 error = sm_init_zone(ftl, zone_num);
871
872 if (error)
873 return ERR_PTR(error);
874 }
875 return zone;
876 }
877
878
879 /* ----------------- cache handling ------------------------------------------*/
880
881 /* Initialize the one block cache */
882 static void sm_cache_init(struct sm_ftl *ftl)
883 {
884 ftl->cache_data_invalid_bitmap = 0xFFFFFFFF;
885 ftl->cache_clean = 1;
886 ftl->cache_zone = -1;
887 ftl->cache_block = -1;
888 /*memset(ftl->cache_data, 0xAA, ftl->block_size);*/
889 }
890
891 /* Put sector in one block cache */
892 static void sm_cache_put(struct sm_ftl *ftl, char *buffer, int boffset)
893 {
894 memcpy(ftl->cache_data + boffset, buffer, SM_SECTOR_SIZE);
895 clear_bit(boffset / SM_SECTOR_SIZE, &ftl->cache_data_invalid_bitmap);
896 ftl->cache_clean = 0;
897 }
898
899 /* Read a sector from the cache */
900 static int sm_cache_get(struct sm_ftl *ftl, char *buffer, int boffset)
901 {
902 if (test_bit(boffset / SM_SECTOR_SIZE,
903 &ftl->cache_data_invalid_bitmap))
904 return -1;
905
906 memcpy(buffer, ftl->cache_data + boffset, SM_SECTOR_SIZE);
907 return 0;
908 }
909
910 /* Write the cache to hardware */
911 static int sm_cache_flush(struct sm_ftl *ftl)
912 {
913 struct ftl_zone *zone;
914
915 int sector_num;
916 uint16_t write_sector;
917 int zone_num = ftl->cache_zone;
918 int block_num;
919
920 if (ftl->cache_clean)
921 return 0;
922
923 if (ftl->unstable)
924 return -EIO;
925
926 BUG_ON(zone_num < 0);
927 zone = &ftl->zones[zone_num];
928 block_num = zone->lba_to_phys_table[ftl->cache_block];
929
930
931 /* Try to read all unread areas of the cache block*/
932 for_each_set_bit(sector_num, &ftl->cache_data_invalid_bitmap,
933 ftl->block_size / SM_SECTOR_SIZE) {
934
935 if (!sm_read_sector(ftl,
936 zone_num, block_num, sector_num * SM_SECTOR_SIZE,
937 ftl->cache_data + sector_num * SM_SECTOR_SIZE, NULL))
938 clear_bit(sector_num,
939 &ftl->cache_data_invalid_bitmap);
940 }
941 restart:
942
943 if (ftl->unstable)
944 return -EIO;
945
946 /* If there are no spare blocks, */
947 /* we could still continue by erasing/writing the current block,
948 but for such worn out media it doesn't worth the trouble,
949 and the dangers */
950 if (kfifo_out(&zone->free_sectors,
951 (unsigned char *)&write_sector, 2) != 2) {
952 dbg("no free sectors for write!");
953 return -EIO;
954 }
955
956
957 if (sm_write_block(ftl, ftl->cache_data, zone_num, write_sector,
958 ftl->cache_block, ftl->cache_data_invalid_bitmap))
959 goto restart;
960
961 /* Update the FTL table */
962 zone->lba_to_phys_table[ftl->cache_block] = write_sector;
963
964 /* Write succesfull, so erase and free the old block */
965 if (block_num > 0)
966 sm_erase_block(ftl, zone_num, block_num, 1);
967
968 sm_cache_init(ftl);
969 return 0;
970 }
971
972
973 /* flush timer, runs a second after last write */
974 static void sm_cache_flush_timer(struct timer_list *t)
975 {
976 struct sm_ftl *ftl = from_timer(ftl, t, timer);
977 queue_work(cache_flush_workqueue, &ftl->flush_work);
978 }
979
980 /* cache flush work, kicked by timer */
981 static void sm_cache_flush_work(struct work_struct *work)
982 {
983 struct sm_ftl *ftl = container_of(work, struct sm_ftl, flush_work);
984 mutex_lock(&ftl->mutex);
985 sm_cache_flush(ftl);
986 mutex_unlock(&ftl->mutex);
987 return;
988 }
989
990 /* ---------------- outside interface -------------------------------------- */
991
992 /* outside interface: read a sector */
993 static int sm_read(struct mtd_blktrans_dev *dev,
994 unsigned long sect_no, char *buf)
995 {
996 struct sm_ftl *ftl = dev->priv;
997 struct ftl_zone *zone;
998 int error = 0, in_cache = 0;
999 int zone_num, block, boffset;
1000
1001 sm_break_offset(ftl, sect_no << 9, &zone_num, &block, &boffset);
1002 mutex_lock(&ftl->mutex);
1003
1004
1005 zone = sm_get_zone(ftl, zone_num);
1006 if (IS_ERR(zone)) {
1007 error = PTR_ERR(zone);
1008 goto unlock;
1009 }
1010
1011 /* Have to look at cache first */
1012 if (ftl->cache_zone == zone_num && ftl->cache_block == block) {
1013 in_cache = 1;
1014 if (!sm_cache_get(ftl, buf, boffset))
1015 goto unlock;
1016 }
1017
1018 /* Translate the block and return if doesn't exist in the table */
1019 block = zone->lba_to_phys_table[block];
1020
1021 if (block == -1) {
1022 memset(buf, 0xFF, SM_SECTOR_SIZE);
1023 goto unlock;
1024 }
1025
1026 if (sm_read_sector(ftl, zone_num, block, boffset, buf, NULL)) {
1027 error = -EIO;
1028 goto unlock;
1029 }
1030
1031 if (in_cache)
1032 sm_cache_put(ftl, buf, boffset);
1033 unlock:
1034 mutex_unlock(&ftl->mutex);
1035 return error;
1036 }
1037
1038 /* outside interface: write a sector */
1039 static int sm_write(struct mtd_blktrans_dev *dev,
1040 unsigned long sec_no, char *buf)
1041 {
1042 struct sm_ftl *ftl = dev->priv;
1043 struct ftl_zone *zone;
1044 int error = 0, zone_num, block, boffset;
1045
1046 BUG_ON(ftl->readonly);
1047 sm_break_offset(ftl, sec_no << 9, &zone_num, &block, &boffset);
1048
1049 /* No need in flush thread running now */
1050 del_timer(&ftl->timer);
1051 mutex_lock(&ftl->mutex);
1052
1053 zone = sm_get_zone(ftl, zone_num);
1054 if (IS_ERR(zone)) {
1055 error = PTR_ERR(zone);
1056 goto unlock;
1057 }
1058
1059 /* If entry is not in cache, flush it */
1060 if (ftl->cache_block != block || ftl->cache_zone != zone_num) {
1061
1062 error = sm_cache_flush(ftl);
1063 if (error)
1064 goto unlock;
1065
1066 ftl->cache_block = block;
1067 ftl->cache_zone = zone_num;
1068 }
1069
1070 sm_cache_put(ftl, buf, boffset);
1071 unlock:
1072 mod_timer(&ftl->timer, jiffies + msecs_to_jiffies(cache_timeout));
1073 mutex_unlock(&ftl->mutex);
1074 return error;
1075 }
1076
1077 /* outside interface: flush everything */
1078 static int sm_flush(struct mtd_blktrans_dev *dev)
1079 {
1080 struct sm_ftl *ftl = dev->priv;
1081 int retval;
1082
1083 mutex_lock(&ftl->mutex);
1084 retval = sm_cache_flush(ftl);
1085 mutex_unlock(&ftl->mutex);
1086 return retval;
1087 }
1088
1089 /* outside interface: device is released */
1090 static void sm_release(struct mtd_blktrans_dev *dev)
1091 {
1092 struct sm_ftl *ftl = dev->priv;
1093
1094 mutex_lock(&ftl->mutex);
1095 del_timer_sync(&ftl->timer);
1096 cancel_work_sync(&ftl->flush_work);
1097 sm_cache_flush(ftl);
1098 mutex_unlock(&ftl->mutex);
1099 }
1100
1101 /* outside interface: get geometry */
1102 static int sm_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
1103 {
1104 struct sm_ftl *ftl = dev->priv;
1105 geo->heads = ftl->heads;
1106 geo->sectors = ftl->sectors;
1107 geo->cylinders = ftl->cylinders;
1108 return 0;
1109 }
1110
1111 /* external interface: main initialization function */
1112 static void sm_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
1113 {
1114 struct mtd_blktrans_dev *trans;
1115 struct sm_ftl *ftl;
1116
1117 /* Allocate & initialize our private structure */
1118 ftl = kzalloc(sizeof(struct sm_ftl), GFP_KERNEL);
1119 if (!ftl)
1120 goto error1;
1121
1122
1123 mutex_init(&ftl->mutex);
1124 timer_setup(&ftl->timer, sm_cache_flush_timer, 0);
1125 INIT_WORK(&ftl->flush_work, sm_cache_flush_work);
1126
1127 /* Read media information */
1128 if (sm_get_media_info(ftl, mtd)) {
1129 dbg("found unsupported mtd device, aborting");
1130 goto error2;
1131 }
1132
1133
1134 /* Allocate temporary CIS buffer for read retry support */
1135 ftl->cis_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
1136 if (!ftl->cis_buffer)
1137 goto error2;
1138
1139 /* Allocate zone array, it will be initialized on demand */
1140 ftl->zones = kcalloc(ftl->zone_count, sizeof(struct ftl_zone),
1141 GFP_KERNEL);
1142 if (!ftl->zones)
1143 goto error3;
1144
1145 /* Allocate the cache*/
1146 ftl->cache_data = kzalloc(ftl->block_size, GFP_KERNEL);
1147
1148 if (!ftl->cache_data)
1149 goto error4;
1150
1151 sm_cache_init(ftl);
1152
1153
1154 /* Allocate upper layer structure and initialize it */
1155 trans = kzalloc(sizeof(struct mtd_blktrans_dev), GFP_KERNEL);
1156 if (!trans)
1157 goto error5;
1158
1159 ftl->trans = trans;
1160 trans->priv = ftl;
1161
1162 trans->tr = tr;
1163 trans->mtd = mtd;
1164 trans->devnum = -1;
1165 trans->size = (ftl->block_size * ftl->max_lba * ftl->zone_count) >> 9;
1166 trans->readonly = ftl->readonly;
1167
1168 if (sm_find_cis(ftl)) {
1169 dbg("CIS not found on mtd device, aborting");
1170 goto error6;
1171 }
1172
1173 ftl->disk_attributes = sm_create_sysfs_attributes(ftl);
1174 if (!ftl->disk_attributes)
1175 goto error6;
1176 trans->disk_attributes = ftl->disk_attributes;
1177
1178 sm_printk("Found %d MiB xD/SmartMedia FTL on mtd%d",
1179 (int)(mtd->size / (1024 * 1024)), mtd->index);
1180
1181 dbg("FTL layout:");
1182 dbg("%d zone(s), each consists of %d blocks (+%d spares)",
1183 ftl->zone_count, ftl->max_lba,
1184 ftl->zone_size - ftl->max_lba);
1185 dbg("each block consists of %d bytes",
1186 ftl->block_size);
1187
1188
1189 /* Register device*/
1190 if (add_mtd_blktrans_dev(trans)) {
1191 dbg("error in mtdblktrans layer");
1192 goto error6;
1193 }
1194 return;
1195 error6:
1196 kfree(trans);
1197 error5:
1198 kfree(ftl->cache_data);
1199 error4:
1200 kfree(ftl->zones);
1201 error3:
1202 kfree(ftl->cis_buffer);
1203 error2:
1204 kfree(ftl);
1205 error1:
1206 return;
1207 }
1208
1209 /* main interface: device {surprise,} removal */
1210 static void sm_remove_dev(struct mtd_blktrans_dev *dev)
1211 {
1212 struct sm_ftl *ftl = dev->priv;
1213 int i;
1214
1215 del_mtd_blktrans_dev(dev);
1216 ftl->trans = NULL;
1217
1218 for (i = 0 ; i < ftl->zone_count; i++) {
1219
1220 if (!ftl->zones[i].initialized)
1221 continue;
1222
1223 kfree(ftl->zones[i].lba_to_phys_table);
1224 kfifo_free(&ftl->zones[i].free_sectors);
1225 }
1226
1227 sm_delete_sysfs_attributes(ftl);
1228 kfree(ftl->cis_buffer);
1229 kfree(ftl->zones);
1230 kfree(ftl->cache_data);
1231 kfree(ftl);
1232 }
1233
1234 static struct mtd_blktrans_ops sm_ftl_ops = {
1235 .name = "smblk",
1236 .major = 0,
1237 .part_bits = SM_FTL_PARTN_BITS,
1238 .blksize = SM_SECTOR_SIZE,
1239 .getgeo = sm_getgeo,
1240
1241 .add_mtd = sm_add_mtd,
1242 .remove_dev = sm_remove_dev,
1243
1244 .readsect = sm_read,
1245 .writesect = sm_write,
1246
1247 .flush = sm_flush,
1248 .release = sm_release,
1249
1250 .owner = THIS_MODULE,
1251 };
1252
1253 static __init int sm_module_init(void)
1254 {
1255 int error = 0;
1256
1257 cache_flush_workqueue = create_freezable_workqueue("smflush");
1258 if (!cache_flush_workqueue)
1259 return -ENOMEM;
1260
1261 error = register_mtd_blktrans(&sm_ftl_ops);
1262 if (error)
1263 destroy_workqueue(cache_flush_workqueue);
1264 return error;
1265
1266 }
1267
1268 static void __exit sm_module_exit(void)
1269 {
1270 destroy_workqueue(cache_flush_workqueue);
1271 deregister_mtd_blktrans(&sm_ftl_ops);
1272 }
1273
1274 module_init(sm_module_init);
1275 module_exit(sm_module_exit);
1276
1277 MODULE_LICENSE("GPL");
1278 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1279 MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");
Linux with added FPC-III support