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Merge tag 'io_uring-5.11-2021-01-16' of git://git.kernel.dk/linux-block
[linux/fpc-iii.git] / drivers / mtd / sm_ftl.c
blob4d1ae25507ab3878df5d0c2e3791e04d0c29e5fb
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright © 2009 - Maxim Levitsky
4 * SmartMedia/xD translation layer
5 */
6
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/random.h>
10 #include <linux/hdreg.h>
11 #include <linux/kthread.h>
12 #include <linux/freezer.h>
13 #include <linux/sysfs.h>
14 #include <linux/bitops.h>
15 #include <linux/slab.h>
16 #include <linux/mtd/nand-ecc-sw-hamming.h>
17 #include "nand/raw/sm_common.h"
18 #include "sm_ftl.h"
19
20
21
22 static struct workqueue_struct *cache_flush_workqueue;
23
24 static int cache_timeout = 1000;
25 module_param(cache_timeout, int, S_IRUGO);
26 MODULE_PARM_DESC(cache_timeout,
27 "Timeout (in ms) for cache flush (1000 ms default");
28
29 static int debug;
30 module_param(debug, int, S_IRUGO | S_IWUSR);
31 MODULE_PARM_DESC(debug, "Debug level (0-2)");
32
33
34 /* ------------------- sysfs attributes ---------------------------------- */
35 struct sm_sysfs_attribute {
36 struct device_attribute dev_attr;
37 char *data;
38 int len;
39 };
40
41 static 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
54 static 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;
94 error4:
95 kfree(attributes);
96 error3:
97 kfree(vendor_attribute);
98 error2:
99 kfree(vendor);
100 error1:
101 return NULL;
102 }
103
104 static 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
129 static 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 */
148 static 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
174 static 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 */
192 static 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 */
206 static 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
217 static int sm_correct_sector(uint8_t *buffer, struct sm_oob *oob)
218 {
219 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC);
220 uint8_t ecc[3];
221
222 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order);
223 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc1, SM_SMALL_PAGE,
224 sm_order) < 0)
225 return -EIO;
226
227 buffer += SM_SMALL_PAGE;
228
229 ecc_sw_hamming_calculate(buffer, SM_SMALL_PAGE, ecc, sm_order);
230 if (ecc_sw_hamming_correct(buffer, ecc, oob->ecc2, SM_SMALL_PAGE,
231 sm_order) < 0)
232 return -EIO;
233 return 0;
234 }
235
236 /* Reads a sector + oob*/
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 if (buffer)
250 memset(buffer, 0xFF, SM_SECTOR_SIZE);
251 return 0;
252 }
253
254 /* User might not need the oob, but we do for data verification */
255 if (!oob)
256 oob = &tmp_oob;
257
258 ops.mode = ftl->smallpagenand ? MTD_OPS_RAW : MTD_OPS_PLACE_OOB;
259 ops.ooboffs = 0;
260 ops.ooblen = SM_OOB_SIZE;
261 ops.oobbuf = (void *)oob;
262 ops.len = SM_SECTOR_SIZE;
263 ops.datbuf = buffer;
264
265 again:
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 */
320 static 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 */
367 static 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 bool sm_order = IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_HAMMING_SMC);
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);
379 restart:
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 ecc_sw_hamming_calculate(buf + boffset,
399 SM_SMALL_PAGE, oob.ecc1,
400 sm_order);
401
402 ecc_sw_hamming_calculate(buf + boffset + SM_SMALL_PAGE,
403 SM_SMALL_PAGE, oob.ecc2,
404 sm_order);
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. */
433 static 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 */
460 static 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;
491 error:
492 sm_mark_block_bad(ftl, zone_num, block);
493 return -EIO;
494 }
495
496 /* Thoroughly test that block is valid. */
497 static 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 --------------------------------- */
536 static 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
553 static 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 */
558 static 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 */
653 static 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 */
673 static 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 */
731 static 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 */
745 static 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 */
868 static 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 */
889 static 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 */
899 static 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 */
907 static 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 */
918 static 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 }
948 restart:
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 */
981 static 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 */
988 static 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 */
1000 static 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);
1040 unlock:
1041 mutex_unlock(&ftl->mutex);
1042 return error;
1043 }
1044
1045 /* outside interface: write a sector */
1046 static 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);
1078 unlock:
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 */
1085 static 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 */
1097 static 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 */
1109 static 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 */
1119 static 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;
1202 error6:
1203 kfree(trans);
1204 error5:
1205 kfree(ftl->cache_data);
1206 error4:
1207 kfree(ftl->zones);
1208 error3:
1209 kfree(ftl->cis_buffer);
1210 error2:
1211 kfree(ftl);
1212 error1:
1213 return;
1214 }
1215
1216 /* main interface: device {surprise,} removal */
1217 static 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
1241 static 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
1260 static __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
1275 static void __exit sm_module_exit(void)
1276 {
1277 destroy_workqueue(cache_flush_workqueue);
1278 deregister_mtd_blktrans(&sm_ftl_ops);
1279 }
1280
1281 module_init(sm_module_init);
1282 module_exit(sm_module_exit);
1283
1284 MODULE_LICENSE("GPL");
1285 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1286 MODULE_DESCRIPTION("Smartmedia/xD mtd translation layer");
Linux with added FPC-III support