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Sean Younge27a9962005-06-16 09:49:33 +01001/*
2 * rfd_ftl.c -- resident flash disk (flash translation layer)
3 *
4 * Copyright (C) 2005 Sean Young <sean@mess.org>
5 *
Sean Young683b30c2006-05-17 12:45:34 +01006 * $Id: rfd_ftl.c,v 1.8 2006/01/15 12:51:44 sean Exp $
Sean Younge27a9962005-06-16 09:49:33 +01007 *
8 * This type of flash translation layer (FTL) is used by the Embedded BIOS
9 * by General Software. It is known as the Resident Flash Disk (RFD), see:
10 *
11 * http://www.gensw.com/pages/prod/bios/rfd.htm
12 *
13 * based on ftl.c
14 */
15
16#include <linux/hdreg.h>
17#include <linux/init.h>
18#include <linux/mtd/blktrans.h>
19#include <linux/mtd/mtd.h>
20#include <linux/vmalloc.h>
Tim Schmielaude259682006-01-08 01:02:05 -080021#include <linux/slab.h>
Andrew Mortonb80b5832005-11-08 21:34:27 -080022#include <linux/jiffies.h>
Sean Younge27a9962005-06-16 09:49:33 +010023
24#include <asm/types.h>
25
26#define const_cpu_to_le16 __constant_cpu_to_le16
27
28static int block_size = 0;
29module_param(block_size, int, 0);
30MODULE_PARM_DESC(block_size, "Block size to use by RFD, defaults to erase unit size");
31
32#define PREFIX "rfd_ftl: "
33
Sean Youngbc4117f2005-11-29 11:48:00 +000034/* This major has been assigned by device@lanana.org */
Sean Younge27a9962005-06-16 09:49:33 +010035#ifndef RFD_FTL_MAJOR
Sean Youngbc4117f2005-11-29 11:48:00 +000036#define RFD_FTL_MAJOR 256
Sean Younge27a9962005-06-16 09:49:33 +010037#endif
38
39/* Maximum number of partitions in an FTL region */
40#define PART_BITS 4
41
42/* An erase unit should start with this value */
43#define RFD_MAGIC 0x9193
44
45/* the second value is 0xffff or 0xffc8; function unknown */
46
47/* the third value is always 0xffff, ignored */
48
49/* next is an array of mapping for each corresponding sector */
50#define HEADER_MAP_OFFSET 3
51#define SECTOR_DELETED 0x0000
52#define SECTOR_ZERO 0xfffe
53#define SECTOR_FREE 0xffff
54
55#define SECTOR_SIZE 512
56
57#define SECTORS_PER_TRACK 63
58
59struct block {
60 enum {
61 BLOCK_OK,
62 BLOCK_ERASING,
63 BLOCK_ERASED,
Sean Young683b30c2006-05-17 12:45:34 +010064 BLOCK_UNUSED,
Sean Younge27a9962005-06-16 09:49:33 +010065 BLOCK_FAILED
66 } state;
67 int free_sectors;
68 int used_sectors;
69 int erases;
70 u_long offset;
71};
72
73struct partition {
74 struct mtd_blktrans_dev mbd;
75
76 u_int block_size; /* size of erase unit */
77 u_int total_blocks; /* number of erase units */
78 u_int header_sectors_per_block; /* header sectors in erase unit */
79 u_int data_sectors_per_block; /* data sectors in erase unit */
80 u_int sector_count; /* sectors in translated disk */
81 u_int header_size; /* bytes in header sector */
82 int reserved_block; /* block next up for reclaim */
83 int current_block; /* block to write to */
84 u16 *header_cache; /* cached header */
85
86 int is_reclaiming;
87 int cylinders;
88 int errors;
89 u_long *sector_map;
90 struct block *blocks;
91};
92
93static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf);
94
95static int build_block_map(struct partition *part, int block_no)
96{
97 struct block *block = &part->blocks[block_no];
98 int i;
Thomas Gleixner97894cd2005-11-07 11:15:26 +000099
Sean Younge27a9962005-06-16 09:49:33 +0100100 block->offset = part->block_size * block_no;
101
102 if (le16_to_cpu(part->header_cache[0]) != RFD_MAGIC) {
Sean Young683b30c2006-05-17 12:45:34 +0100103 block->state = BLOCK_UNUSED;
104 return -ENOENT;
Sean Younge27a9962005-06-16 09:49:33 +0100105 }
106
107 block->state = BLOCK_OK;
108
109 for (i=0; i<part->data_sectors_per_block; i++) {
110 u16 entry;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000111
Sean Younge27a9962005-06-16 09:49:33 +0100112 entry = le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i]);
113
114 if (entry == SECTOR_DELETED)
115 continue;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000116
Sean Younge27a9962005-06-16 09:49:33 +0100117 if (entry == SECTOR_FREE) {
118 block->free_sectors++;
119 continue;
120 }
121
122 if (entry == SECTOR_ZERO)
123 entry = 0;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000124
Sean Younge27a9962005-06-16 09:49:33 +0100125 if (entry >= part->sector_count) {
Sean Young683b30c2006-05-17 12:45:34 +0100126 printk(KERN_WARNING PREFIX
Sean Younge27a9962005-06-16 09:49:33 +0100127 "'%s': unit #%d: entry %d corrupt, "
128 "sector %d out of range\n",
129 part->mbd.mtd->name, block_no, i, entry);
130 continue;
131 }
132
133 if (part->sector_map[entry] != -1) {
Sean Young683b30c2006-05-17 12:45:34 +0100134 printk(KERN_WARNING PREFIX
Sean Younge27a9962005-06-16 09:49:33 +0100135 "'%s': more than one entry for sector %d\n",
136 part->mbd.mtd->name, entry);
137 part->errors = 1;
138 continue;
139 }
140
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000141 part->sector_map[entry] = block->offset +
Sean Younge27a9962005-06-16 09:49:33 +0100142 (i + part->header_sectors_per_block) * SECTOR_SIZE;
143
144 block->used_sectors++;
145 }
146
147 if (block->free_sectors == part->data_sectors_per_block)
148 part->reserved_block = block_no;
149
150 return 0;
151}
152
153static int scan_header(struct partition *part)
154{
155 int sectors_per_block;
156 int i, rc = -ENOMEM;
157 int blocks_found;
158 size_t retlen;
159
160 sectors_per_block = part->block_size / SECTOR_SIZE;
161 part->total_blocks = part->mbd.mtd->size / part->block_size;
162
163 if (part->total_blocks < 2)
164 return -ENOENT;
165
166 /* each erase block has three bytes header, followed by the map */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000167 part->header_sectors_per_block =
168 ((HEADER_MAP_OFFSET + sectors_per_block) *
Sean Young683b30c2006-05-17 12:45:34 +0100169 sizeof(u16) + SECTOR_SIZE - 1) / SECTOR_SIZE;
Sean Younge27a9962005-06-16 09:49:33 +0100170
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000171 part->data_sectors_per_block = sectors_per_block -
Sean Younge27a9962005-06-16 09:49:33 +0100172 part->header_sectors_per_block;
173
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000174 part->header_size = (HEADER_MAP_OFFSET +
Sean Younge27a9962005-06-16 09:49:33 +0100175 part->data_sectors_per_block) * sizeof(u16);
176
177 part->cylinders = (part->data_sectors_per_block *
178 (part->total_blocks - 1) - 1) / SECTORS_PER_TRACK;
179
180 part->sector_count = part->cylinders * SECTORS_PER_TRACK;
181
182 part->current_block = -1;
183 part->reserved_block = -1;
184 part->is_reclaiming = 0;
185
186 part->header_cache = kmalloc(part->header_size, GFP_KERNEL);
187 if (!part->header_cache)
188 goto err;
189
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000190 part->blocks = kcalloc(part->total_blocks, sizeof(struct block),
Sean Younge27a9962005-06-16 09:49:33 +0100191 GFP_KERNEL);
192 if (!part->blocks)
193 goto err;
194
195 part->sector_map = vmalloc(part->sector_count * sizeof(u_long));
196 if (!part->sector_map) {
197 printk(KERN_ERR PREFIX "'%s': unable to allocate memory for "
198 "sector map", part->mbd.mtd->name);
199 goto err;
200 }
201
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000202 for (i=0; i<part->sector_count; i++)
Sean Younge27a9962005-06-16 09:49:33 +0100203 part->sector_map[i] = -1;
204
205 for (i=0, blocks_found=0; i<part->total_blocks; i++) {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000206 rc = part->mbd.mtd->read(part->mbd.mtd,
Sean Younge27a9962005-06-16 09:49:33 +0100207 i * part->block_size, part->header_size,
208 &retlen, (u_char*)part->header_cache);
209
210 if (!rc && retlen != part->header_size)
211 rc = -EIO;
212
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000213 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100214 goto err;
215
216 if (!build_block_map(part, i))
217 blocks_found++;
218 }
219
220 if (blocks_found == 0) {
221 printk(KERN_NOTICE PREFIX "no RFD magic found in '%s'\n",
222 part->mbd.mtd->name);
223 rc = -ENOENT;
224 goto err;
225 }
226
227 if (part->reserved_block == -1) {
Sean Young683b30c2006-05-17 12:45:34 +0100228 printk(KERN_WARNING PREFIX "'%s': no empty erase unit found\n",
Sean Younge27a9962005-06-16 09:49:33 +0100229 part->mbd.mtd->name);
230
231 part->errors = 1;
232 }
233
234 return 0;
235
236err:
237 vfree(part->sector_map);
238 kfree(part->header_cache);
239 kfree(part->blocks);
240
241 return rc;
242}
243
244static int rfd_ftl_readsect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
245{
246 struct partition *part = (struct partition*)dev;
247 u_long addr;
248 size_t retlen;
249 int rc;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000250
Sean Younge27a9962005-06-16 09:49:33 +0100251 if (sector >= part->sector_count)
252 return -EIO;
253
254 addr = part->sector_map[sector];
255 if (addr != -1) {
256 rc = part->mbd.mtd->read(part->mbd.mtd, addr, SECTOR_SIZE,
257 &retlen, (u_char*)buf);
258 if (!rc && retlen != SECTOR_SIZE)
259 rc = -EIO;
260
261 if (rc) {
262 printk(KERN_WARNING PREFIX "error reading '%s' at "
263 "0x%lx\n", part->mbd.mtd->name, addr);
264 return rc;
265 }
266 } else
267 memset(buf, 0, SECTOR_SIZE);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000268
Sean Younge27a9962005-06-16 09:49:33 +0100269 return 0;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000270}
Sean Younge27a9962005-06-16 09:49:33 +0100271
272static void erase_callback(struct erase_info *erase)
273{
274 struct partition *part;
275 u16 magic;
276 int i, rc;
277 size_t retlen;
278
279 part = (struct partition*)erase->priv;
280
281 i = erase->addr / part->block_size;
282 if (i >= part->total_blocks || part->blocks[i].offset != erase->addr) {
283 printk(KERN_ERR PREFIX "erase callback for unknown offset %x "
284 "on '%s'\n", erase->addr, part->mbd.mtd->name);
285 return;
286 }
287
288 if (erase->state != MTD_ERASE_DONE) {
289 printk(KERN_WARNING PREFIX "erase failed at 0x%x on '%s', "
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000290 "state %d\n", erase->addr,
Sean Younge27a9962005-06-16 09:49:33 +0100291 part->mbd.mtd->name, erase->state);
292
293 part->blocks[i].state = BLOCK_FAILED;
294 part->blocks[i].free_sectors = 0;
295 part->blocks[i].used_sectors = 0;
296
297 kfree(erase);
298
299 return;
300 }
301
302 magic = const_cpu_to_le16(RFD_MAGIC);
303
304 part->blocks[i].state = BLOCK_ERASED;
305 part->blocks[i].free_sectors = part->data_sectors_per_block;
306 part->blocks[i].used_sectors = 0;
307 part->blocks[i].erases++;
308
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000309 rc = part->mbd.mtd->write(part->mbd.mtd,
310 part->blocks[i].offset, sizeof(magic), &retlen,
Sean Younge27a9962005-06-16 09:49:33 +0100311 (u_char*)&magic);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000312
Sean Younge27a9962005-06-16 09:49:33 +0100313 if (!rc && retlen != sizeof(magic))
314 rc = -EIO;
315
316 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100317 printk(KERN_ERR PREFIX "'%s': unable to write RFD "
Sean Younge27a9962005-06-16 09:49:33 +0100318 "header at 0x%lx\n",
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000319 part->mbd.mtd->name,
Sean Younge27a9962005-06-16 09:49:33 +0100320 part->blocks[i].offset);
321 part->blocks[i].state = BLOCK_FAILED;
322 }
323 else
324 part->blocks[i].state = BLOCK_OK;
325
326 kfree(erase);
327}
328
329static int erase_block(struct partition *part, int block)
330{
331 struct erase_info *erase;
332 int rc = -ENOMEM;
333
334 erase = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
335 if (!erase)
336 goto err;
337
338 erase->mtd = part->mbd.mtd;
339 erase->callback = erase_callback;
340 erase->addr = part->blocks[block].offset;
341 erase->len = part->block_size;
342 erase->priv = (u_long)part;
343
344 part->blocks[block].state = BLOCK_ERASING;
345 part->blocks[block].free_sectors = 0;
346
347 rc = part->mbd.mtd->erase(part->mbd.mtd, erase);
348
349 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100350 printk(KERN_ERR PREFIX "erase of region %x,%x on '%s' "
Sean Younge27a9962005-06-16 09:49:33 +0100351 "failed\n", erase->addr, erase->len,
352 part->mbd.mtd->name);
353 kfree(erase);
354 }
355
356err:
357 return rc;
358}
359
360static int move_block_contents(struct partition *part, int block_no, u_long *old_sector)
361{
362 void *sector_data;
363 u16 *map;
364 size_t retlen;
365 int i, rc = -ENOMEM;
366
367 part->is_reclaiming = 1;
368
369 sector_data = kmalloc(SECTOR_SIZE, GFP_KERNEL);
370 if (!sector_data)
371 goto err3;
372
373 map = kmalloc(part->header_size, GFP_KERNEL);
374 if (!map)
375 goto err2;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000376
377 rc = part->mbd.mtd->read(part->mbd.mtd,
378 part->blocks[block_no].offset, part->header_size,
Sean Younge27a9962005-06-16 09:49:33 +0100379 &retlen, (u_char*)map);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000380
Sean Younge27a9962005-06-16 09:49:33 +0100381 if (!rc && retlen != part->header_size)
382 rc = -EIO;
383
384 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100385 printk(KERN_ERR PREFIX "error reading '%s' at "
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000386 "0x%lx\n", part->mbd.mtd->name,
Sean Younge27a9962005-06-16 09:49:33 +0100387 part->blocks[block_no].offset);
388
389 goto err;
390 }
391
392 for (i=0; i<part->data_sectors_per_block; i++) {
393 u16 entry = le16_to_cpu(map[HEADER_MAP_OFFSET + i]);
394 u_long addr;
395
396
397 if (entry == SECTOR_FREE || entry == SECTOR_DELETED)
398 continue;
399
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000400 if (entry == SECTOR_ZERO)
Sean Younge27a9962005-06-16 09:49:33 +0100401 entry = 0;
402
403 /* already warned about and ignored in build_block_map() */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000404 if (entry >= part->sector_count)
Sean Younge27a9962005-06-16 09:49:33 +0100405 continue;
406
407 addr = part->blocks[block_no].offset +
408 (i + part->header_sectors_per_block) * SECTOR_SIZE;
409
410 if (*old_sector == addr) {
411 *old_sector = -1;
412 if (!part->blocks[block_no].used_sectors--) {
413 rc = erase_block(part, block_no);
414 break;
415 }
416 continue;
417 }
418 rc = part->mbd.mtd->read(part->mbd.mtd, addr,
419 SECTOR_SIZE, &retlen, sector_data);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000420
Sean Younge27a9962005-06-16 09:49:33 +0100421 if (!rc && retlen != SECTOR_SIZE)
422 rc = -EIO;
423
424 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100425 printk(KERN_ERR PREFIX "'%s': Unable to "
Sean Younge27a9962005-06-16 09:49:33 +0100426 "read sector for relocation\n",
427 part->mbd.mtd->name);
428
429 goto err;
430 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000431
Sean Younge27a9962005-06-16 09:49:33 +0100432 rc = rfd_ftl_writesect((struct mtd_blktrans_dev*)part,
433 entry, sector_data);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000434
435 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100436 goto err;
437 }
438
439err:
440 kfree(map);
441err2:
442 kfree(sector_data);
443err3:
444 part->is_reclaiming = 0;
445
446 return rc;
447}
448
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000449static int reclaim_block(struct partition *part, u_long *old_sector)
Sean Younge27a9962005-06-16 09:49:33 +0100450{
451 int block, best_block, score, old_sector_block;
452 int rc;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000453
Sean Younge27a9962005-06-16 09:49:33 +0100454 /* we have a race if sync doesn't exist */
455 if (part->mbd.mtd->sync)
456 part->mbd.mtd->sync(part->mbd.mtd);
457
458 score = 0x7fffffff; /* MAX_INT */
459 best_block = -1;
460 if (*old_sector != -1)
461 old_sector_block = *old_sector / part->block_size;
462 else
463 old_sector_block = -1;
464
465 for (block=0; block<part->total_blocks; block++) {
466 int this_score;
467
468 if (block == part->reserved_block)
469 continue;
470
471 /*
472 * Postpone reclaiming if there is a free sector as
473 * more removed sectors is more efficient (have to move
474 * less).
475 */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000476 if (part->blocks[block].free_sectors)
Sean Younge27a9962005-06-16 09:49:33 +0100477 return 0;
478
479 this_score = part->blocks[block].used_sectors;
480
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000481 if (block == old_sector_block)
Sean Younge27a9962005-06-16 09:49:33 +0100482 this_score--;
483 else {
484 /* no point in moving a full block */
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000485 if (part->blocks[block].used_sectors ==
Sean Younge27a9962005-06-16 09:49:33 +0100486 part->data_sectors_per_block)
487 continue;
488 }
489
490 this_score += part->blocks[block].erases;
491
492 if (this_score < score) {
493 best_block = block;
494 score = this_score;
495 }
496 }
497
498 if (best_block == -1)
499 return -ENOSPC;
500
501 part->current_block = -1;
502 part->reserved_block = best_block;
503
504 pr_debug("reclaim_block: reclaiming block #%d with %d used "
505 "%d free sectors\n", best_block,
506 part->blocks[best_block].used_sectors,
507 part->blocks[best_block].free_sectors);
508
509 if (part->blocks[best_block].used_sectors)
510 rc = move_block_contents(part, best_block, old_sector);
511 else
512 rc = erase_block(part, best_block);
513
514 return rc;
515}
516
517/*
518 * IMPROVE: It would be best to choose the block with the most deleted sectors,
519 * because if we fill that one up first it'll have the most chance of having
520 * the least live sectors at reclaim.
521 */
Sean Young683b30c2006-05-17 12:45:34 +0100522static int find_free_block(struct partition *part)
Sean Younge27a9962005-06-16 09:49:33 +0100523{
524 int block, stop;
525
526 block = part->current_block == -1 ?
527 jiffies % part->total_blocks : part->current_block;
528 stop = block;
529
530 do {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000531 if (part->blocks[block].free_sectors &&
Sean Younge27a9962005-06-16 09:49:33 +0100532 block != part->reserved_block)
533 return block;
534
Sean Young683b30c2006-05-17 12:45:34 +0100535 if (part->blocks[block].state == BLOCK_UNUSED)
536 erase_block(part, block);
537
Sean Younge27a9962005-06-16 09:49:33 +0100538 if (++block >= part->total_blocks)
539 block = 0;
540
541 } while (block != stop);
542
543 return -1;
544}
545
Sean Young683b30c2006-05-17 12:45:34 +0100546static int find_writable_block(struct partition *part, u_long *old_sector)
Sean Younge27a9962005-06-16 09:49:33 +0100547{
548 int rc, block;
549 size_t retlen;
550
551 block = find_free_block(part);
552
553 if (block == -1) {
554 if (!part->is_reclaiming) {
555 rc = reclaim_block(part, old_sector);
556 if (rc)
557 goto err;
558
559 block = find_free_block(part);
560 }
561
562 if (block == -1) {
563 rc = -ENOSPC;
564 goto err;
565 }
566 }
567
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000568 rc = part->mbd.mtd->read(part->mbd.mtd, part->blocks[block].offset,
Sean Younge27a9962005-06-16 09:49:33 +0100569 part->header_size, &retlen, (u_char*)part->header_cache);
570
571 if (!rc && retlen != part->header_size)
572 rc = -EIO;
573
574 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100575 printk(KERN_ERR PREFIX "'%s': unable to read header at "
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000576 "0x%lx\n", part->mbd.mtd->name,
Sean Younge27a9962005-06-16 09:49:33 +0100577 part->blocks[block].offset);
578 goto err;
579 }
580
581 part->current_block = block;
582
583err:
584 return rc;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000585}
Sean Younge27a9962005-06-16 09:49:33 +0100586
587static int mark_sector_deleted(struct partition *part, u_long old_addr)
588{
589 int block, offset, rc;
590 u_long addr;
591 size_t retlen;
592 u16 del = const_cpu_to_le16(SECTOR_DELETED);
593
594 block = old_addr / part->block_size;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000595 offset = (old_addr % part->block_size) / SECTOR_SIZE -
Sean Younge27a9962005-06-16 09:49:33 +0100596 part->header_sectors_per_block;
597
598 addr = part->blocks[block].offset +
599 (HEADER_MAP_OFFSET + offset) * sizeof(u16);
600 rc = part->mbd.mtd->write(part->mbd.mtd, addr,
601 sizeof(del), &retlen, (u_char*)&del);
602
603 if (!rc && retlen != sizeof(del))
604 rc = -EIO;
605
606 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100607 printk(KERN_ERR PREFIX "error writing '%s' at "
Sean Younge27a9962005-06-16 09:49:33 +0100608 "0x%lx\n", part->mbd.mtd->name, addr);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000609 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100610 goto err;
611 }
612 if (block == part->current_block)
613 part->header_cache[offset + HEADER_MAP_OFFSET] = del;
614
615 part->blocks[block].used_sectors--;
616
617 if (!part->blocks[block].used_sectors &&
618 !part->blocks[block].free_sectors)
619 rc = erase_block(part, block);
620
621err:
622 return rc;
623}
624
625static int find_free_sector(const struct partition *part, const struct block *block)
626{
627 int i, stop;
628
629 i = stop = part->data_sectors_per_block - block->free_sectors;
630
631 do {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000632 if (le16_to_cpu(part->header_cache[HEADER_MAP_OFFSET + i])
Sean Younge27a9962005-06-16 09:49:33 +0100633 == SECTOR_FREE)
634 return i;
635
636 if (++i == part->data_sectors_per_block)
637 i = 0;
638 }
639 while(i != stop);
640
641 return -1;
642}
643
644static int do_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf, ulong *old_addr)
645{
646 struct partition *part = (struct partition*)dev;
647 struct block *block;
648 u_long addr;
649 int i;
650 int rc;
651 size_t retlen;
652 u16 entry;
653
654 if (part->current_block == -1 ||
655 !part->blocks[part->current_block].free_sectors) {
656
Sean Young683b30c2006-05-17 12:45:34 +0100657 rc = find_writable_block(part, old_addr);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000658 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100659 goto err;
660 }
661
662 block = &part->blocks[part->current_block];
663
664 i = find_free_sector(part, block);
665
666 if (i < 0) {
667 rc = -ENOSPC;
668 goto err;
669 }
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000670
671 addr = (i + part->header_sectors_per_block) * SECTOR_SIZE +
Sean Younge27a9962005-06-16 09:49:33 +0100672 block->offset;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000673 rc = part->mbd.mtd->write(part->mbd.mtd,
Sean Younge27a9962005-06-16 09:49:33 +0100674 addr, SECTOR_SIZE, &retlen, (u_char*)buf);
675
676 if (!rc && retlen != SECTOR_SIZE)
677 rc = -EIO;
678
679 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100680 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
Sean Younge27a9962005-06-16 09:49:33 +0100681 part->mbd.mtd->name, addr);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000682 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100683 goto err;
684 }
685
686 part->sector_map[sector] = addr;
687
688 entry = cpu_to_le16(sector == 0 ? SECTOR_ZERO : sector);
689
690 part->header_cache[i + HEADER_MAP_OFFSET] = entry;
691
692 addr = block->offset + (HEADER_MAP_OFFSET + i) * sizeof(u16);
693 rc = part->mbd.mtd->write(part->mbd.mtd, addr,
694 sizeof(entry), &retlen, (u_char*)&entry);
695
696 if (!rc && retlen != sizeof(entry))
697 rc = -EIO;
698
699 if (rc) {
Sean Young683b30c2006-05-17 12:45:34 +0100700 printk(KERN_ERR PREFIX "error writing '%s' at 0x%lx\n",
Sean Younge27a9962005-06-16 09:49:33 +0100701 part->mbd.mtd->name, addr);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000702 if (rc)
Sean Younge27a9962005-06-16 09:49:33 +0100703 goto err;
704 }
705 block->used_sectors++;
706 block->free_sectors--;
707
708err:
709 return rc;
710}
711
712static int rfd_ftl_writesect(struct mtd_blktrans_dev *dev, u_long sector, char *buf)
713{
714 struct partition *part = (struct partition*)dev;
715 u_long old_addr;
716 int i;
717 int rc = 0;
718
719 pr_debug("rfd_ftl_writesect(sector=0x%lx)\n", sector);
720
721 if (part->reserved_block == -1) {
722 rc = -EACCES;
723 goto err;
724 }
725
726 if (sector >= part->sector_count) {
727 rc = -EIO;
728 goto err;
729 }
730
731 old_addr = part->sector_map[sector];
732
733 for (i=0; i<SECTOR_SIZE; i++) {
734 if (!buf[i])
735 continue;
736
737 rc = do_writesect(dev, sector, buf, &old_addr);
738 if (rc)
739 goto err;
740 break;
741 }
742
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000743 if (i == SECTOR_SIZE)
Sean Younge27a9962005-06-16 09:49:33 +0100744 part->sector_map[sector] = -1;
745
746 if (old_addr != -1)
747 rc = mark_sector_deleted(part, old_addr);
748
749err:
750 return rc;
751}
752
753static int rfd_ftl_getgeo(struct mtd_blktrans_dev *dev, struct hd_geometry *geo)
754{
755 struct partition *part = (struct partition*)dev;
756
757 geo->heads = 1;
758 geo->sectors = SECTORS_PER_TRACK;
759 geo->cylinders = part->cylinders;
760
761 return 0;
762}
763
764static void rfd_ftl_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
765{
766 struct partition *part;
767
768 if (mtd->type != MTD_NORFLASH)
769 return;
770
771 part = kcalloc(1, sizeof(struct partition), GFP_KERNEL);
772 if (!part)
773 return;
774
775 part->mbd.mtd = mtd;
776
777 if (block_size)
778 part->block_size = block_size;
779 else {
780 if (!mtd->erasesize) {
Sean Young683b30c2006-05-17 12:45:34 +0100781 printk(KERN_WARNING PREFIX "please provide block_size");
Sean Younge27a9962005-06-16 09:49:33 +0100782 return;
783 }
784 else
785 part->block_size = mtd->erasesize;
786 }
787
788 if (scan_header(part) == 0) {
789 part->mbd.size = part->sector_count;
790 part->mbd.blksize = SECTOR_SIZE;
791 part->mbd.tr = tr;
792 part->mbd.devnum = -1;
793 if (!(mtd->flags & MTD_WRITEABLE))
794 part->mbd.readonly = 1;
795 else if (part->errors) {
Sean Young683b30c2006-05-17 12:45:34 +0100796 printk(KERN_WARNING PREFIX "'%s': errors found, "
797 "setting read-only\n", mtd->name);
Sean Younge27a9962005-06-16 09:49:33 +0100798 part->mbd.readonly = 1;
799 }
800
801 printk(KERN_INFO PREFIX "name: '%s' type: %d flags %x\n",
802 mtd->name, mtd->type, mtd->flags);
803
804 if (!add_mtd_blktrans_dev((void*)part))
805 return;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000806 }
Sean Younge27a9962005-06-16 09:49:33 +0100807
808 kfree(part);
809}
810
811static void rfd_ftl_remove_dev(struct mtd_blktrans_dev *dev)
812{
813 struct partition *part = (struct partition*)dev;
814 int i;
815
816 for (i=0; i<part->total_blocks; i++) {
817 pr_debug("rfd_ftl_remove_dev:'%s': erase unit #%02d: %d erases\n",
818 part->mbd.mtd->name, i, part->blocks[i].erases);
819 }
820
821 del_mtd_blktrans_dev(dev);
822 vfree(part->sector_map);
823 kfree(part->header_cache);
824 kfree(part->blocks);
825 kfree(part);
826}
827
828struct mtd_blktrans_ops rfd_ftl_tr = {
829 .name = "rfd",
830 .major = RFD_FTL_MAJOR,
831 .part_bits = PART_BITS,
832 .readsect = rfd_ftl_readsect,
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000833 .writesect = rfd_ftl_writesect,
Sean Younge27a9962005-06-16 09:49:33 +0100834 .getgeo = rfd_ftl_getgeo,
835 .add_mtd = rfd_ftl_add_mtd,
836 .remove_dev = rfd_ftl_remove_dev,
837 .owner = THIS_MODULE,
838};
839
840static int __init init_rfd_ftl(void)
841{
842 return register_mtd_blktrans(&rfd_ftl_tr);
843}
844
845static void __exit cleanup_rfd_ftl(void)
846{
847 deregister_mtd_blktrans(&rfd_ftl_tr);
848}
849
850module_init(init_rfd_ftl);
851module_exit(cleanup_rfd_ftl);
852
853MODULE_LICENSE("GPL");
854MODULE_AUTHOR("Sean Young <sean@mess.org>");
855MODULE_DESCRIPTION("Support code for RFD Flash Translation Layer, "
856 "used by General Software's Embedded BIOS");
857