forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathftl.c
1110 lines (919 loc) · 31.3 KB
/
ftl.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* This version ported to the Linux-MTD system by [email protected]
*
* Fixes: Arnaldo Carvalho de Melo <[email protected]>
* - fixes some leaks on failure in build_maps and ftl_notify_add, cleanups
*
* Based on:
*/
/*======================================================================
A Flash Translation Layer memory card driver
This driver implements a disk-like block device driver with an
apparent block size of 512 bytes for flash memory cards.
ftl_cs.c 1.62 2000/02/01 00:59:04
The contents of this file are subject to the Mozilla Public
License Version 1.1 (the "License"); you may not use this file
except in compliance with the License. You may obtain a copy of
the License at http://www.mozilla.org/MPL/
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
The initial developer of the original code is David A. Hinds
<[email protected]>. Portions created by David A. Hinds
are Copyright © 1999 David A. Hinds. All Rights Reserved.
Alternatively, the contents of this file may be used under the
terms of the GNU General Public License version 2 (the "GPL"), in
which case the provisions of the GPL are applicable instead of the
above. If you wish to allow the use of your version of this file
only under the terms of the GPL and not to allow others to use
your version of this file under the MPL, indicate your decision
by deleting the provisions above and replace them with the notice
and other provisions required by the GPL. If you do not delete
the provisions above, a recipient may use your version of this
file under either the MPL or the GPL.
LEGAL NOTE: The FTL format is patented by M-Systems. They have
granted a license for its use with PCMCIA devices:
"M-Systems grants a royalty-free, non-exclusive license under
any presently existing M-Systems intellectual property rights
necessary for the design and development of FTL-compatible
drivers, file systems and utilities using the data formats with
PCMCIA PC Cards as described in the PCMCIA Flash Translation
Layer (FTL) Specification."
Use of the FTL format for non-PCMCIA applications may be an
infringement of these patents. For additional information,
contact M-Systems directly. M-Systems since acquired by Sandisk.
======================================================================*/
#include <linux/mtd/blktrans.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
/*#define PSYCHO_DEBUG */
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/hdreg.h>
#include <linux/vmalloc.h>
#include <linux/blkpg.h>
#include <linux/uaccess.h>
#include <linux/mtd/ftl.h>
/*====================================================================*/
/* Parameters that can be set with 'insmod' */
static int shuffle_freq = 50;
module_param(shuffle_freq, int, 0);
/*====================================================================*/
/* Major device # for FTL device */
#ifndef FTL_MAJOR
#define FTL_MAJOR 44
#endif
/*====================================================================*/
/* Maximum number of separate memory devices we'll allow */
#define MAX_DEV 4
/* Maximum number of regions per device */
#define MAX_REGION 4
/* Maximum number of partitions in an FTL region */
#define PART_BITS 4
/* Maximum number of outstanding erase requests per socket */
#define MAX_ERASE 8
/* Sector size -- shouldn't need to change */
#define SECTOR_SIZE 512
/* Each memory region corresponds to a minor device */
typedef struct partition_t {
struct mtd_blktrans_dev mbd;
uint32_t state;
uint32_t *VirtualBlockMap;
uint32_t FreeTotal;
struct eun_info_t {
uint32_t Offset;
uint32_t EraseCount;
uint32_t Free;
uint32_t Deleted;
} *EUNInfo;
struct xfer_info_t {
uint32_t Offset;
uint32_t EraseCount;
uint16_t state;
} *XferInfo;
uint16_t bam_index;
uint32_t *bam_cache;
uint16_t DataUnits;
uint32_t BlocksPerUnit;
erase_unit_header_t header;
} partition_t;
/* Partition state flags */
#define FTL_FORMATTED 0x01
/* Transfer unit states */
#define XFER_UNKNOWN 0x00
#define XFER_ERASING 0x01
#define XFER_ERASED 0x02
#define XFER_PREPARED 0x03
#define XFER_FAILED 0x04
/*====================================================================*/
static void ftl_erase_callback(struct erase_info *done);
/*======================================================================
Scan_header() checks to see if a memory region contains an FTL
partition. build_maps() reads all the erase unit headers, builds
the erase unit map, and then builds the virtual page map.
======================================================================*/
static int scan_header(partition_t *part)
{
erase_unit_header_t header;
loff_t offset, max_offset;
size_t ret;
int err;
part->header.FormattedSize = 0;
max_offset = (0x100000<part->mbd.mtd->size)?0x100000:part->mbd.mtd->size;
/* Search first megabyte for a valid FTL header */
for (offset = 0;
(offset + sizeof(header)) < max_offset;
offset += part->mbd.mtd->erasesize ? : 0x2000) {
err = mtd_read(part->mbd.mtd, offset, sizeof(header), &ret,
(unsigned char *)&header);
if (err)
return err;
if (strcmp(header.DataOrgTuple+3, "FTL100") == 0) break;
}
if (offset == max_offset) {
printk(KERN_NOTICE "ftl_cs: FTL header not found.\n");
return -ENOENT;
}
if (header.BlockSize != 9 ||
(header.EraseUnitSize < 10) || (header.EraseUnitSize > 31) ||
(header.NumTransferUnits >= le16_to_cpu(header.NumEraseUnits))) {
printk(KERN_NOTICE "ftl_cs: FTL header corrupt!\n");
return -1;
}
if ((1 << header.EraseUnitSize) != part->mbd.mtd->erasesize) {
printk(KERN_NOTICE "ftl: FTL EraseUnitSize %x != MTD erasesize %x\n",
1 << header.EraseUnitSize,part->mbd.mtd->erasesize);
return -1;
}
part->header = header;
return 0;
}
static int build_maps(partition_t *part)
{
erase_unit_header_t header;
uint16_t xvalid, xtrans, i;
unsigned blocks, j;
int hdr_ok, ret = -1;
ssize_t retval;
loff_t offset;
/* Set up erase unit maps */
part->DataUnits = le16_to_cpu(part->header.NumEraseUnits) -
part->header.NumTransferUnits;
part->EUNInfo = kmalloc(part->DataUnits * sizeof(struct eun_info_t),
GFP_KERNEL);
if (!part->EUNInfo)
goto out;
for (i = 0; i < part->DataUnits; i++)
part->EUNInfo[i].Offset = 0xffffffff;
part->XferInfo =
kmalloc(part->header.NumTransferUnits * sizeof(struct xfer_info_t),
GFP_KERNEL);
if (!part->XferInfo)
goto out_EUNInfo;
xvalid = xtrans = 0;
for (i = 0; i < le16_to_cpu(part->header.NumEraseUnits); i++) {
offset = ((i + le16_to_cpu(part->header.FirstPhysicalEUN))
<< part->header.EraseUnitSize);
ret = mtd_read(part->mbd.mtd, offset, sizeof(header), &retval,
(unsigned char *)&header);
if (ret)
goto out_XferInfo;
ret = -1;
/* Is this a transfer partition? */
hdr_ok = (strcmp(header.DataOrgTuple+3, "FTL100") == 0);
if (hdr_ok && (le16_to_cpu(header.LogicalEUN) < part->DataUnits) &&
(part->EUNInfo[le16_to_cpu(header.LogicalEUN)].Offset == 0xffffffff)) {
part->EUNInfo[le16_to_cpu(header.LogicalEUN)].Offset = offset;
part->EUNInfo[le16_to_cpu(header.LogicalEUN)].EraseCount =
le32_to_cpu(header.EraseCount);
xvalid++;
} else {
if (xtrans == part->header.NumTransferUnits) {
printk(KERN_NOTICE "ftl_cs: format error: too many "
"transfer units!\n");
goto out_XferInfo;
}
if (hdr_ok && (le16_to_cpu(header.LogicalEUN) == 0xffff)) {
part->XferInfo[xtrans].state = XFER_PREPARED;
part->XferInfo[xtrans].EraseCount = le32_to_cpu(header.EraseCount);
} else {
part->XferInfo[xtrans].state = XFER_UNKNOWN;
/* Pick anything reasonable for the erase count */
part->XferInfo[xtrans].EraseCount =
le32_to_cpu(part->header.EraseCount);
}
part->XferInfo[xtrans].Offset = offset;
xtrans++;
}
}
/* Check for format trouble */
header = part->header;
if ((xtrans != header.NumTransferUnits) ||
(xvalid+xtrans != le16_to_cpu(header.NumEraseUnits))) {
printk(KERN_NOTICE "ftl_cs: format error: erase units "
"don't add up!\n");
goto out_XferInfo;
}
/* Set up virtual page map */
blocks = le32_to_cpu(header.FormattedSize) >> header.BlockSize;
part->VirtualBlockMap = vmalloc(blocks * sizeof(uint32_t));
if (!part->VirtualBlockMap)
goto out_XferInfo;
memset(part->VirtualBlockMap, 0xff, blocks * sizeof(uint32_t));
part->BlocksPerUnit = (1 << header.EraseUnitSize) >> header.BlockSize;
part->bam_cache = kmalloc(part->BlocksPerUnit * sizeof(uint32_t),
GFP_KERNEL);
if (!part->bam_cache)
goto out_VirtualBlockMap;
part->bam_index = 0xffff;
part->FreeTotal = 0;
for (i = 0; i < part->DataUnits; i++) {
part->EUNInfo[i].Free = 0;
part->EUNInfo[i].Deleted = 0;
offset = part->EUNInfo[i].Offset + le32_to_cpu(header.BAMOffset);
ret = mtd_read(part->mbd.mtd, offset,
part->BlocksPerUnit * sizeof(uint32_t), &retval,
(unsigned char *)part->bam_cache);
if (ret)
goto out_bam_cache;
for (j = 0; j < part->BlocksPerUnit; j++) {
if (BLOCK_FREE(le32_to_cpu(part->bam_cache[j]))) {
part->EUNInfo[i].Free++;
part->FreeTotal++;
} else if ((BLOCK_TYPE(le32_to_cpu(part->bam_cache[j])) == BLOCK_DATA) &&
(BLOCK_NUMBER(le32_to_cpu(part->bam_cache[j])) < blocks))
part->VirtualBlockMap[BLOCK_NUMBER(le32_to_cpu(part->bam_cache[j]))] =
(i << header.EraseUnitSize) + (j << header.BlockSize);
else if (BLOCK_DELETED(le32_to_cpu(part->bam_cache[j])))
part->EUNInfo[i].Deleted++;
}
}
ret = 0;
goto out;
out_bam_cache:
kfree(part->bam_cache);
out_VirtualBlockMap:
vfree(part->VirtualBlockMap);
out_XferInfo:
kfree(part->XferInfo);
out_EUNInfo:
kfree(part->EUNInfo);
out:
return ret;
} /* build_maps */
/*======================================================================
Erase_xfer() schedules an asynchronous erase operation for a
transfer unit.
======================================================================*/
static int erase_xfer(partition_t *part,
uint16_t xfernum)
{
int ret;
struct xfer_info_t *xfer;
struct erase_info *erase;
xfer = &part->XferInfo[xfernum];
pr_debug("ftl_cs: erasing xfer unit at 0x%x\n", xfer->Offset);
xfer->state = XFER_ERASING;
/* Is there a free erase slot? Always in MTD. */
erase=kmalloc(sizeof(struct erase_info), GFP_KERNEL);
if (!erase)
return -ENOMEM;
erase->mtd = part->mbd.mtd;
erase->callback = ftl_erase_callback;
erase->addr = xfer->Offset;
erase->len = 1 << part->header.EraseUnitSize;
erase->priv = (u_long)part;
ret = mtd_erase(part->mbd.mtd, erase);
if (!ret)
xfer->EraseCount++;
else
kfree(erase);
return ret;
} /* erase_xfer */
/*======================================================================
Prepare_xfer() takes a freshly erased transfer unit and gives
it an appropriate header.
======================================================================*/
static void ftl_erase_callback(struct erase_info *erase)
{
partition_t *part;
struct xfer_info_t *xfer;
int i;
/* Look up the transfer unit */
part = (partition_t *)(erase->priv);
for (i = 0; i < part->header.NumTransferUnits; i++)
if (part->XferInfo[i].Offset == erase->addr) break;
if (i == part->header.NumTransferUnits) {
printk(KERN_NOTICE "ftl_cs: internal error: "
"erase lookup failed!\n");
return;
}
xfer = &part->XferInfo[i];
if (erase->state == MTD_ERASE_DONE)
xfer->state = XFER_ERASED;
else {
xfer->state = XFER_FAILED;
printk(KERN_NOTICE "ftl_cs: erase failed: state = %d\n",
erase->state);
}
kfree(erase);
} /* ftl_erase_callback */
static int prepare_xfer(partition_t *part, int i)
{
erase_unit_header_t header;
struct xfer_info_t *xfer;
int nbam, ret;
uint32_t ctl;
ssize_t retlen;
loff_t offset;
xfer = &part->XferInfo[i];
xfer->state = XFER_FAILED;
pr_debug("ftl_cs: preparing xfer unit at 0x%x\n", xfer->Offset);
/* Write the transfer unit header */
header = part->header;
header.LogicalEUN = cpu_to_le16(0xffff);
header.EraseCount = cpu_to_le32(xfer->EraseCount);
ret = mtd_write(part->mbd.mtd, xfer->Offset, sizeof(header), &retlen,
(u_char *)&header);
if (ret) {
return ret;
}
/* Write the BAM stub */
nbam = (part->BlocksPerUnit * sizeof(uint32_t) +
le32_to_cpu(part->header.BAMOffset) + SECTOR_SIZE - 1) / SECTOR_SIZE;
offset = xfer->Offset + le32_to_cpu(part->header.BAMOffset);
ctl = cpu_to_le32(BLOCK_CONTROL);
for (i = 0; i < nbam; i++, offset += sizeof(uint32_t)) {
ret = mtd_write(part->mbd.mtd, offset, sizeof(uint32_t), &retlen,
(u_char *)&ctl);
if (ret)
return ret;
}
xfer->state = XFER_PREPARED;
return 0;
} /* prepare_xfer */
/*======================================================================
Copy_erase_unit() takes a full erase block and a transfer unit,
copies everything to the transfer unit, then swaps the block
pointers.
All data blocks are copied to the corresponding blocks in the
target unit, so the virtual block map does not need to be
updated.
======================================================================*/
static int copy_erase_unit(partition_t *part, uint16_t srcunit,
uint16_t xferunit)
{
u_char buf[SECTOR_SIZE];
struct eun_info_t *eun;
struct xfer_info_t *xfer;
uint32_t src, dest, free, i;
uint16_t unit;
int ret;
ssize_t retlen;
loff_t offset;
uint16_t srcunitswap = cpu_to_le16(srcunit);
eun = &part->EUNInfo[srcunit];
xfer = &part->XferInfo[xferunit];
pr_debug("ftl_cs: copying block 0x%x to 0x%x\n",
eun->Offset, xfer->Offset);
/* Read current BAM */
if (part->bam_index != srcunit) {
offset = eun->Offset + le32_to_cpu(part->header.BAMOffset);
ret = mtd_read(part->mbd.mtd, offset,
part->BlocksPerUnit * sizeof(uint32_t), &retlen,
(u_char *)(part->bam_cache));
/* mark the cache bad, in case we get an error later */
part->bam_index = 0xffff;
if (ret) {
printk( KERN_WARNING "ftl: Failed to read BAM cache in copy_erase_unit()!\n");
return ret;
}
}
/* Write the LogicalEUN for the transfer unit */
xfer->state = XFER_UNKNOWN;
offset = xfer->Offset + 20; /* Bad! */
unit = cpu_to_le16(0x7fff);
ret = mtd_write(part->mbd.mtd, offset, sizeof(uint16_t), &retlen,
(u_char *)&unit);
if (ret) {
printk( KERN_WARNING "ftl: Failed to write back to BAM cache in copy_erase_unit()!\n");
return ret;
}
/* Copy all data blocks from source unit to transfer unit */
src = eun->Offset; dest = xfer->Offset;
free = 0;
ret = 0;
for (i = 0; i < part->BlocksPerUnit; i++) {
switch (BLOCK_TYPE(le32_to_cpu(part->bam_cache[i]))) {
case BLOCK_CONTROL:
/* This gets updated later */
break;
case BLOCK_DATA:
case BLOCK_REPLACEMENT:
ret = mtd_read(part->mbd.mtd, src, SECTOR_SIZE, &retlen,
(u_char *)buf);
if (ret) {
printk(KERN_WARNING "ftl: Error reading old xfer unit in copy_erase_unit\n");
return ret;
}
ret = mtd_write(part->mbd.mtd, dest, SECTOR_SIZE, &retlen,
(u_char *)buf);
if (ret) {
printk(KERN_WARNING "ftl: Error writing new xfer unit in copy_erase_unit\n");
return ret;
}
break;
default:
/* All other blocks must be free */
part->bam_cache[i] = cpu_to_le32(0xffffffff);
free++;
break;
}
src += SECTOR_SIZE;
dest += SECTOR_SIZE;
}
/* Write the BAM to the transfer unit */
ret = mtd_write(part->mbd.mtd,
xfer->Offset + le32_to_cpu(part->header.BAMOffset),
part->BlocksPerUnit * sizeof(int32_t),
&retlen,
(u_char *)part->bam_cache);
if (ret) {
printk( KERN_WARNING "ftl: Error writing BAM in copy_erase_unit\n");
return ret;
}
/* All clear? Then update the LogicalEUN again */
ret = mtd_write(part->mbd.mtd, xfer->Offset + 20, sizeof(uint16_t),
&retlen, (u_char *)&srcunitswap);
if (ret) {
printk(KERN_WARNING "ftl: Error writing new LogicalEUN in copy_erase_unit\n");
return ret;
}
/* Update the maps and usage stats*/
swap(xfer->EraseCount, eun->EraseCount);
swap(xfer->Offset, eun->Offset);
part->FreeTotal -= eun->Free;
part->FreeTotal += free;
eun->Free = free;
eun->Deleted = 0;
/* Now, the cache should be valid for the new block */
part->bam_index = srcunit;
return 0;
} /* copy_erase_unit */
/*======================================================================
reclaim_block() picks a full erase unit and a transfer unit and
then calls copy_erase_unit() to copy one to the other. Then, it
schedules an erase on the expired block.
What's a good way to decide which transfer unit and which erase
unit to use? Beats me. My way is to always pick the transfer
unit with the fewest erases, and usually pick the data unit with
the most deleted blocks. But with a small probability, pick the
oldest data unit instead. This means that we generally postpone
the next reclamation as long as possible, but shuffle static
stuff around a bit for wear leveling.
======================================================================*/
static int reclaim_block(partition_t *part)
{
uint16_t i, eun, xfer;
uint32_t best;
int queued, ret;
pr_debug("ftl_cs: reclaiming space...\n");
pr_debug("NumTransferUnits == %x\n", part->header.NumTransferUnits);
/* Pick the least erased transfer unit */
best = 0xffffffff; xfer = 0xffff;
do {
queued = 0;
for (i = 0; i < part->header.NumTransferUnits; i++) {
int n=0;
if (part->XferInfo[i].state == XFER_UNKNOWN) {
pr_debug("XferInfo[%d].state == XFER_UNKNOWN\n",i);
n=1;
erase_xfer(part, i);
}
if (part->XferInfo[i].state == XFER_ERASING) {
pr_debug("XferInfo[%d].state == XFER_ERASING\n",i);
n=1;
queued = 1;
}
else if (part->XferInfo[i].state == XFER_ERASED) {
pr_debug("XferInfo[%d].state == XFER_ERASED\n",i);
n=1;
prepare_xfer(part, i);
}
if (part->XferInfo[i].state == XFER_PREPARED) {
pr_debug("XferInfo[%d].state == XFER_PREPARED\n",i);
n=1;
if (part->XferInfo[i].EraseCount <= best) {
best = part->XferInfo[i].EraseCount;
xfer = i;
}
}
if (!n)
pr_debug("XferInfo[%d].state == %x\n",i, part->XferInfo[i].state);
}
if (xfer == 0xffff) {
if (queued) {
pr_debug("ftl_cs: waiting for transfer "
"unit to be prepared...\n");
mtd_sync(part->mbd.mtd);
} else {
static int ne = 0;
if (++ne < 5)
printk(KERN_NOTICE "ftl_cs: reclaim failed: no "
"suitable transfer units!\n");
else
pr_debug("ftl_cs: reclaim failed: no "
"suitable transfer units!\n");
return -EIO;
}
}
} while (xfer == 0xffff);
eun = 0;
if ((jiffies % shuffle_freq) == 0) {
pr_debug("ftl_cs: recycling freshest block...\n");
best = 0xffffffff;
for (i = 0; i < part->DataUnits; i++)
if (part->EUNInfo[i].EraseCount <= best) {
best = part->EUNInfo[i].EraseCount;
eun = i;
}
} else {
best = 0;
for (i = 0; i < part->DataUnits; i++)
if (part->EUNInfo[i].Deleted >= best) {
best = part->EUNInfo[i].Deleted;
eun = i;
}
if (best == 0) {
static int ne = 0;
if (++ne < 5)
printk(KERN_NOTICE "ftl_cs: reclaim failed: "
"no free blocks!\n");
else
pr_debug("ftl_cs: reclaim failed: "
"no free blocks!\n");
return -EIO;
}
}
ret = copy_erase_unit(part, eun, xfer);
if (!ret)
erase_xfer(part, xfer);
else
printk(KERN_NOTICE "ftl_cs: copy_erase_unit failed!\n");
return ret;
} /* reclaim_block */
/*======================================================================
Find_free() searches for a free block. If necessary, it updates
the BAM cache for the erase unit containing the free block. It
returns the block index -- the erase unit is just the currently
cached unit. If there are no free blocks, it returns 0 -- this
is never a valid data block because it contains the header.
======================================================================*/
#ifdef PSYCHO_DEBUG
static void dump_lists(partition_t *part)
{
int i;
printk(KERN_DEBUG "ftl_cs: Free total = %d\n", part->FreeTotal);
for (i = 0; i < part->DataUnits; i++)
printk(KERN_DEBUG "ftl_cs: unit %d: %d phys, %d free, "
"%d deleted\n", i,
part->EUNInfo[i].Offset >> part->header.EraseUnitSize,
part->EUNInfo[i].Free, part->EUNInfo[i].Deleted);
}
#endif
static uint32_t find_free(partition_t *part)
{
uint16_t stop, eun;
uint32_t blk;
size_t retlen;
int ret;
/* Find an erase unit with some free space */
stop = (part->bam_index == 0xffff) ? 0 : part->bam_index;
eun = stop;
do {
if (part->EUNInfo[eun].Free != 0) break;
/* Wrap around at end of table */
if (++eun == part->DataUnits) eun = 0;
} while (eun != stop);
if (part->EUNInfo[eun].Free == 0)
return 0;
/* Is this unit's BAM cached? */
if (eun != part->bam_index) {
/* Invalidate cache */
part->bam_index = 0xffff;
ret = mtd_read(part->mbd.mtd,
part->EUNInfo[eun].Offset + le32_to_cpu(part->header.BAMOffset),
part->BlocksPerUnit * sizeof(uint32_t),
&retlen,
(u_char *)(part->bam_cache));
if (ret) {
printk(KERN_WARNING"ftl: Error reading BAM in find_free\n");
return 0;
}
part->bam_index = eun;
}
/* Find a free block */
for (blk = 0; blk < part->BlocksPerUnit; blk++)
if (BLOCK_FREE(le32_to_cpu(part->bam_cache[blk]))) break;
if (blk == part->BlocksPerUnit) {
#ifdef PSYCHO_DEBUG
static int ne = 0;
if (++ne == 1)
dump_lists(part);
#endif
printk(KERN_NOTICE "ftl_cs: bad free list!\n");
return 0;
}
pr_debug("ftl_cs: found free block at %d in %d\n", blk, eun);
return blk;
} /* find_free */
/*======================================================================
Read a series of sectors from an FTL partition.
======================================================================*/
static int ftl_read(partition_t *part, caddr_t buffer,
u_long sector, u_long nblocks)
{
uint32_t log_addr, bsize;
u_long i;
int ret;
size_t offset, retlen;
pr_debug("ftl_cs: ftl_read(0x%p, 0x%lx, %ld)\n",
part, sector, nblocks);
if (!(part->state & FTL_FORMATTED)) {
printk(KERN_NOTICE "ftl_cs: bad partition\n");
return -EIO;
}
bsize = 1 << part->header.EraseUnitSize;
for (i = 0; i < nblocks; i++) {
if (((sector+i) * SECTOR_SIZE) >= le32_to_cpu(part->header.FormattedSize)) {
printk(KERN_NOTICE "ftl_cs: bad read offset\n");
return -EIO;
}
log_addr = part->VirtualBlockMap[sector+i];
if (log_addr == 0xffffffff)
memset(buffer, 0, SECTOR_SIZE);
else {
offset = (part->EUNInfo[log_addr / bsize].Offset
+ (log_addr % bsize));
ret = mtd_read(part->mbd.mtd, offset, SECTOR_SIZE, &retlen,
(u_char *)buffer);
if (ret) {
printk(KERN_WARNING "Error reading MTD device in ftl_read()\n");
return ret;
}
}
buffer += SECTOR_SIZE;
}
return 0;
} /* ftl_read */
/*======================================================================
Write a series of sectors to an FTL partition
======================================================================*/
static int set_bam_entry(partition_t *part, uint32_t log_addr,
uint32_t virt_addr)
{
uint32_t bsize, blk, le_virt_addr;
#ifdef PSYCHO_DEBUG
uint32_t old_addr;
#endif
uint16_t eun;
int ret;
size_t retlen, offset;
pr_debug("ftl_cs: set_bam_entry(0x%p, 0x%x, 0x%x)\n",
part, log_addr, virt_addr);
bsize = 1 << part->header.EraseUnitSize;
eun = log_addr / bsize;
blk = (log_addr % bsize) / SECTOR_SIZE;
offset = (part->EUNInfo[eun].Offset + blk * sizeof(uint32_t) +
le32_to_cpu(part->header.BAMOffset));
#ifdef PSYCHO_DEBUG
ret = mtd_read(part->mbd.mtd, offset, sizeof(uint32_t), &retlen,
(u_char *)&old_addr);
if (ret) {
printk(KERN_WARNING"ftl: Error reading old_addr in set_bam_entry: %d\n",ret);
return ret;
}
old_addr = le32_to_cpu(old_addr);
if (((virt_addr == 0xfffffffe) && !BLOCK_FREE(old_addr)) ||
((virt_addr == 0) && (BLOCK_TYPE(old_addr) != BLOCK_DATA)) ||
(!BLOCK_DELETED(virt_addr) && (old_addr != 0xfffffffe))) {
static int ne = 0;
if (++ne < 5) {
printk(KERN_NOTICE "ftl_cs: set_bam_entry() inconsistency!\n");
printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, old = 0x%x"
", new = 0x%x\n", log_addr, old_addr, virt_addr);
}
return -EIO;
}
#endif
le_virt_addr = cpu_to_le32(virt_addr);
if (part->bam_index == eun) {
#ifdef PSYCHO_DEBUG
if (le32_to_cpu(part->bam_cache[blk]) != old_addr) {
static int ne = 0;
if (++ne < 5) {
printk(KERN_NOTICE "ftl_cs: set_bam_entry() "
"inconsistency!\n");
printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, cache"
" = 0x%x\n",
le32_to_cpu(part->bam_cache[blk]), old_addr);
}
return -EIO;
}
#endif
part->bam_cache[blk] = le_virt_addr;
}
ret = mtd_write(part->mbd.mtd, offset, sizeof(uint32_t), &retlen,
(u_char *)&le_virt_addr);
if (ret) {
printk(KERN_NOTICE "ftl_cs: set_bam_entry() failed!\n");
printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, new = 0x%x\n",
log_addr, virt_addr);
}
return ret;
} /* set_bam_entry */
static int ftl_write(partition_t *part, caddr_t buffer,
u_long sector, u_long nblocks)
{
uint32_t bsize, log_addr, virt_addr, old_addr, blk;
u_long i;
int ret;
size_t retlen, offset;
pr_debug("ftl_cs: ftl_write(0x%p, %ld, %ld)\n",
part, sector, nblocks);
if (!(part->state & FTL_FORMATTED)) {
printk(KERN_NOTICE "ftl_cs: bad partition\n");
return -EIO;
}
/* See if we need to reclaim space, before we start */
while (part->FreeTotal < nblocks) {
ret = reclaim_block(part);
if (ret)
return ret;
}
bsize = 1 << part->header.EraseUnitSize;
virt_addr = sector * SECTOR_SIZE | BLOCK_DATA;
for (i = 0; i < nblocks; i++) {
if (virt_addr >= le32_to_cpu(part->header.FormattedSize)) {
printk(KERN_NOTICE "ftl_cs: bad write offset\n");
return -EIO;
}
/* Grab a free block */
blk = find_free(part);
if (blk == 0) {
static int ne = 0;
if (++ne < 5)
printk(KERN_NOTICE "ftl_cs: internal error: "
"no free blocks!\n");
return -ENOSPC;
}
/* Tag the BAM entry, and write the new block */
log_addr = part->bam_index * bsize + blk * SECTOR_SIZE;
part->EUNInfo[part->bam_index].Free--;
part->FreeTotal--;
if (set_bam_entry(part, log_addr, 0xfffffffe))
return -EIO;
part->EUNInfo[part->bam_index].Deleted++;
offset = (part->EUNInfo[part->bam_index].Offset +
blk * SECTOR_SIZE);
ret = mtd_write(part->mbd.mtd, offset, SECTOR_SIZE, &retlen, buffer);
if (ret) {
printk(KERN_NOTICE "ftl_cs: block write failed!\n");
printk(KERN_NOTICE "ftl_cs: log_addr = 0x%x, virt_addr"
" = 0x%x, Offset = 0x%zx\n", log_addr, virt_addr,
offset);
return -EIO;
}
/* Only delete the old entry when the new entry is ready */
old_addr = part->VirtualBlockMap[sector+i];
if (old_addr != 0xffffffff) {
part->VirtualBlockMap[sector+i] = 0xffffffff;
part->EUNInfo[old_addr/bsize].Deleted++;
if (set_bam_entry(part, old_addr, 0))
return -EIO;
}
/* Finally, set up the new pointers */
if (set_bam_entry(part, log_addr, virt_addr))
return -EIO;
part->VirtualBlockMap[sector+i] = log_addr;
part->EUNInfo[part->bam_index].Deleted--;
buffer += SECTOR_SIZE;
virt_addr += SECTOR_SIZE;
}
return 0;
} /* ftl_write */
static int ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
{
partition_t *part = (void *)dev;
u_long sect;
/* Sort of arbitrary: round size down to 4KiB boundary */
sect = le32_to_cpu(part->header.FormattedSize)/SECTOR_SIZE;
geo->heads = 1;
geo->sectors = 8;
geo->cylinders = sect >> 3;
return 0;
}
static int ftl_readsect(struct mtd_blktrans_dev *dev,
unsigned long block, char *buf)
{
return ftl_read((void *)dev, buf, block, 1);
}
static int ftl_writesect(struct mtd_blktrans_dev *dev,
unsigned long block, char *buf)
{