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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * MTD device concatenation layer
3 *
David Woodhousea1452a32010-08-08 20:58:20 +01004 * Copyright © 2002 Robert Kaiser <rkaiser@sysgo.de>
5 * Copyright © 2002-2010 David Woodhouse <dwmw2@infradead.org>
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
7 * NAND support by Christian Gan <cgan@iders.ca>
8 *
David Woodhousea1452a32010-08-08 20:58:20 +01009 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070023 */
24
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#include <linux/kernel.h>
Thomas Gleixner15fdc522005-11-07 00:14:42 +010026#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#include <linux/slab.h>
Thomas Gleixner15fdc522005-11-07 00:14:42 +010028#include <linux/sched.h>
29#include <linux/types.h>
David Howells6e232cf2009-02-12 10:40:05 +000030#include <linux/backing-dev.h>
Thomas Gleixner15fdc522005-11-07 00:14:42 +010031
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <linux/mtd/mtd.h>
33#include <linux/mtd/concat.h>
34
Andrew Morton6c8b44a2006-05-20 10:17:21 +010035#include <asm/div64.h>
36
Linus Torvalds1da177e2005-04-16 15:20:36 -070037/*
38 * Our storage structure:
39 * Subdev points to an array of pointers to struct mtd_info objects
40 * which is allocated along with this structure
41 *
42 */
43struct mtd_concat {
44 struct mtd_info mtd;
45 int num_subdev;
46 struct mtd_info **subdev;
47};
48
49/*
50 * how to calculate the size required for the above structure,
51 * including the pointer array subdev points to:
52 */
53#define SIZEOF_STRUCT_MTD_CONCAT(num_subdev) \
54 ((sizeof(struct mtd_concat) + (num_subdev) * sizeof(struct mtd_info *)))
55
56/*
57 * Given a pointer to the MTD object in the mtd_concat structure,
58 * we can retrieve the pointer to that structure with this macro.
59 */
60#define CONCAT(x) ((struct mtd_concat *)(x))
61
Thomas Gleixner97894cd2005-11-07 11:15:26 +000062/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 * MTD methods which look up the relevant subdevice, translate the
64 * effective address and pass through to the subdevice.
65 */
66
67static int
68concat_read(struct mtd_info *mtd, loff_t from, size_t len,
69 size_t * retlen, u_char * buf)
70{
71 struct mtd_concat *concat = CONCAT(mtd);
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +020072 int ret = 0, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -070073 int i;
74
75 *retlen = 0;
76
77 for (i = 0; i < concat->num_subdev; i++) {
78 struct mtd_info *subdev = concat->subdev[i];
79 size_t size, retsize;
80
81 if (from >= subdev->size) {
82 /* Not destined for this subdev */
83 size = 0;
84 from -= subdev->size;
85 continue;
86 }
87 if (from + len > subdev->size)
88 /* First part goes into this subdev */
89 size = subdev->size - from;
90 else
91 /* Entire transaction goes into this subdev */
92 size = len;
93
94 err = subdev->read(subdev, from, size, &retsize, buf);
95
Thomas Gleixner9a1fcdf2006-05-29 14:56:39 +020096 /* Save information about bitflips! */
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +020097 if (unlikely(err)) {
98 if (err == -EBADMSG) {
99 mtd->ecc_stats.failed++;
Thomas Gleixner9a1fcdf2006-05-29 14:56:39 +0200100 ret = err;
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200101 } else if (err == -EUCLEAN) {
102 mtd->ecc_stats.corrected++;
103 /* Do not overwrite -EBADMSG !! */
104 if (!ret)
105 ret = err;
106 } else
107 return err;
Thomas Gleixner9a1fcdf2006-05-29 14:56:39 +0200108 }
109
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 *retlen += retsize;
111 len -= size;
112 if (len == 0)
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200113 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 buf += size;
116 from = 0;
117 }
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200118 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119}
120
121static int
122concat_write(struct mtd_info *mtd, loff_t to, size_t len,
123 size_t * retlen, const u_char * buf)
124{
125 struct mtd_concat *concat = CONCAT(mtd);
126 int err = -EINVAL;
127 int i;
128
129 if (!(mtd->flags & MTD_WRITEABLE))
130 return -EROFS;
131
132 *retlen = 0;
133
134 for (i = 0; i < concat->num_subdev; i++) {
135 struct mtd_info *subdev = concat->subdev[i];
136 size_t size, retsize;
137
138 if (to >= subdev->size) {
139 size = 0;
140 to -= subdev->size;
141 continue;
142 }
143 if (to + len > subdev->size)
144 size = subdev->size - to;
145 else
146 size = len;
147
148 if (!(subdev->flags & MTD_WRITEABLE))
149 err = -EROFS;
150 else
151 err = subdev->write(subdev, to, size, &retsize, buf);
152
153 if (err)
154 break;
155
156 *retlen += retsize;
157 len -= size;
158 if (len == 0)
159 break;
160
161 err = -EINVAL;
162 buf += size;
163 to = 0;
164 }
165 return err;
166}
167
168static int
Thomas Gleixner9d8522d2006-05-23 16:06:03 +0200169concat_writev(struct mtd_info *mtd, const struct kvec *vecs,
170 unsigned long count, loff_t to, size_t * retlen)
Alexander Belyakove8d32932006-05-17 19:11:16 +0400171{
172 struct mtd_concat *concat = CONCAT(mtd);
173 struct kvec *vecs_copy;
174 unsigned long entry_low, entry_high;
175 size_t total_len = 0;
176 int i;
177 int err = -EINVAL;
178
179 if (!(mtd->flags & MTD_WRITEABLE))
180 return -EROFS;
181
182 *retlen = 0;
183
184 /* Calculate total length of data */
185 for (i = 0; i < count; i++)
186 total_len += vecs[i].iov_len;
187
188 /* Do not allow write past end of device */
189 if ((to + total_len) > mtd->size)
190 return -EINVAL;
191
192 /* Check alignment */
Joern Engel28318772006-05-22 23:18:05 +0200193 if (mtd->writesize > 1) {
David Woodhouse0bf97332007-07-23 13:07:06 +0100194 uint64_t __to = to;
Joern Engel28318772006-05-22 23:18:05 +0200195 if (do_div(__to, mtd->writesize) || (total_len % mtd->writesize))
Alexander Belyakove8d32932006-05-17 19:11:16 +0400196 return -EINVAL;
Andrew Morton6c8b44a2006-05-20 10:17:21 +0100197 }
Alexander Belyakove8d32932006-05-17 19:11:16 +0400198
199 /* make a copy of vecs */
Julia Lawalld80f2662010-05-15 23:23:31 +0200200 vecs_copy = kmemdup(vecs, sizeof(struct kvec) * count, GFP_KERNEL);
Alexander Belyakove8d32932006-05-17 19:11:16 +0400201 if (!vecs_copy)
202 return -ENOMEM;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400203
204 entry_low = 0;
205 for (i = 0; i < concat->num_subdev; i++) {
206 struct mtd_info *subdev = concat->subdev[i];
207 size_t size, wsize, retsize, old_iov_len;
208
209 if (to >= subdev->size) {
210 to -= subdev->size;
211 continue;
212 }
213
Adrian Hunter69423d92008-12-10 13:37:21 +0000214 size = min_t(uint64_t, total_len, subdev->size - to);
Alexander Belyakove8d32932006-05-17 19:11:16 +0400215 wsize = size; /* store for future use */
216
217 entry_high = entry_low;
218 while (entry_high < count) {
219 if (size <= vecs_copy[entry_high].iov_len)
220 break;
221 size -= vecs_copy[entry_high++].iov_len;
222 }
223
224 old_iov_len = vecs_copy[entry_high].iov_len;
225 vecs_copy[entry_high].iov_len = size;
226
227 if (!(subdev->flags & MTD_WRITEABLE))
228 err = -EROFS;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400229 else
230 err = subdev->writev(subdev, &vecs_copy[entry_low],
231 entry_high - entry_low + 1, to, &retsize);
232
233 vecs_copy[entry_high].iov_len = old_iov_len - size;
234 vecs_copy[entry_high].iov_base += size;
235
236 entry_low = entry_high;
237
238 if (err)
239 break;
240
241 *retlen += retsize;
242 total_len -= wsize;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400243
244 if (total_len == 0)
245 break;
246
247 err = -EINVAL;
248 to = 0;
249 }
250
251 kfree(vecs_copy);
252 return err;
253}
254
255static int
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200256concat_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257{
258 struct mtd_concat *concat = CONCAT(mtd);
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200259 struct mtd_oob_ops devops = *ops;
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200260 int i, err, ret = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
Vitaly Wool70145682006-11-03 18:20:38 +0300262 ops->retlen = ops->oobretlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263
264 for (i = 0; i < concat->num_subdev; i++) {
265 struct mtd_info *subdev = concat->subdev[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266
267 if (from >= subdev->size) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 from -= subdev->size;
269 continue;
270 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200272 /* partial read ? */
273 if (from + devops.len > subdev->size)
274 devops.len = subdev->size - from;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200276 err = subdev->read_oob(subdev, from, &devops);
277 ops->retlen += devops.retlen;
Vitaly Wool70145682006-11-03 18:20:38 +0300278 ops->oobretlen += devops.oobretlen;
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200279
280 /* Save information about bitflips! */
281 if (unlikely(err)) {
282 if (err == -EBADMSG) {
283 mtd->ecc_stats.failed++;
284 ret = err;
285 } else if (err == -EUCLEAN) {
286 mtd->ecc_stats.corrected++;
287 /* Do not overwrite -EBADMSG !! */
288 if (!ret)
289 ret = err;
290 } else
291 return err;
292 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
Vitaly Wool70145682006-11-03 18:20:38 +0300294 if (devops.datbuf) {
295 devops.len = ops->len - ops->retlen;
296 if (!devops.len)
297 return ret;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200298 devops.datbuf += devops.retlen;
Vitaly Wool70145682006-11-03 18:20:38 +0300299 }
300 if (devops.oobbuf) {
301 devops.ooblen = ops->ooblen - ops->oobretlen;
302 if (!devops.ooblen)
303 return ret;
304 devops.oobbuf += ops->oobretlen;
305 }
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 from = 0;
308 }
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200309 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310}
311
312static int
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200313concat_write_oob(struct mtd_info *mtd, loff_t to, struct mtd_oob_ops *ops)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314{
315 struct mtd_concat *concat = CONCAT(mtd);
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200316 struct mtd_oob_ops devops = *ops;
317 int i, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700318
319 if (!(mtd->flags & MTD_WRITEABLE))
320 return -EROFS;
321
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200322 ops->retlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
324 for (i = 0; i < concat->num_subdev; i++) {
325 struct mtd_info *subdev = concat->subdev[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
327 if (to >= subdev->size) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 to -= subdev->size;
329 continue;
330 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200332 /* partial write ? */
333 if (to + devops.len > subdev->size)
334 devops.len = subdev->size - to;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200336 err = subdev->write_oob(subdev, to, &devops);
337 ops->retlen += devops.retlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 if (err)
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200339 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700340
Vitaly Wool70145682006-11-03 18:20:38 +0300341 if (devops.datbuf) {
342 devops.len = ops->len - ops->retlen;
343 if (!devops.len)
344 return 0;
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200345 devops.datbuf += devops.retlen;
Vitaly Wool70145682006-11-03 18:20:38 +0300346 }
347 if (devops.oobbuf) {
348 devops.ooblen = ops->ooblen - ops->oobretlen;
349 if (!devops.ooblen)
350 return 0;
351 devops.oobbuf += devops.oobretlen;
352 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 to = 0;
354 }
Thomas Gleixner8593fbc2006-05-29 03:26:58 +0200355 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356}
357
358static void concat_erase_callback(struct erase_info *instr)
359{
360 wake_up((wait_queue_head_t *) instr->priv);
361}
362
363static int concat_dev_erase(struct mtd_info *mtd, struct erase_info *erase)
364{
365 int err;
366 wait_queue_head_t waitq;
367 DECLARE_WAITQUEUE(wait, current);
368
369 /*
370 * This code was stol^H^H^H^Hinspired by mtdchar.c
371 */
372 init_waitqueue_head(&waitq);
373
374 erase->mtd = mtd;
375 erase->callback = concat_erase_callback;
376 erase->priv = (unsigned long) &waitq;
377
378 /*
379 * FIXME: Allow INTERRUPTIBLE. Which means
380 * not having the wait_queue head on the stack.
381 */
382 err = mtd->erase(mtd, erase);
383 if (!err) {
384 set_current_state(TASK_UNINTERRUPTIBLE);
385 add_wait_queue(&waitq, &wait);
386 if (erase->state != MTD_ERASE_DONE
387 && erase->state != MTD_ERASE_FAILED)
388 schedule();
389 remove_wait_queue(&waitq, &wait);
390 set_current_state(TASK_RUNNING);
391
392 err = (erase->state == MTD_ERASE_FAILED) ? -EIO : 0;
393 }
394 return err;
395}
396
397static int concat_erase(struct mtd_info *mtd, struct erase_info *instr)
398{
399 struct mtd_concat *concat = CONCAT(mtd);
400 struct mtd_info *subdev;
401 int i, err;
Adrian Hunter69423d92008-12-10 13:37:21 +0000402 uint64_t length, offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 struct erase_info *erase;
404
405 if (!(mtd->flags & MTD_WRITEABLE))
406 return -EROFS;
407
408 if (instr->addr > concat->mtd.size)
409 return -EINVAL;
410
411 if (instr->len + instr->addr > concat->mtd.size)
412 return -EINVAL;
413
414 /*
415 * Check for proper erase block alignment of the to-be-erased area.
416 * It is easier to do this based on the super device's erase
417 * region info rather than looking at each particular sub-device
418 * in turn.
419 */
420 if (!concat->mtd.numeraseregions) {
421 /* the easy case: device has uniform erase block size */
422 if (instr->addr & (concat->mtd.erasesize - 1))
423 return -EINVAL;
424 if (instr->len & (concat->mtd.erasesize - 1))
425 return -EINVAL;
426 } else {
427 /* device has variable erase size */
428 struct mtd_erase_region_info *erase_regions =
429 concat->mtd.eraseregions;
430
431 /*
432 * Find the erase region where the to-be-erased area begins:
433 */
434 for (i = 0; i < concat->mtd.numeraseregions &&
435 instr->addr >= erase_regions[i].offset; i++) ;
436 --i;
437
438 /*
439 * Now erase_regions[i] is the region in which the
440 * to-be-erased area begins. Verify that the starting
441 * offset is aligned to this region's erase size:
442 */
Roel Kluinebf2e932009-09-18 12:51:49 -0700443 if (i < 0 || instr->addr & (erase_regions[i].erasesize - 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 return -EINVAL;
445
446 /*
447 * now find the erase region where the to-be-erased area ends:
448 */
449 for (; i < concat->mtd.numeraseregions &&
450 (instr->addr + instr->len) >= erase_regions[i].offset;
451 ++i) ;
452 --i;
453 /*
454 * check if the ending offset is aligned to this region's erase size
455 */
Roel Kluinebf2e932009-09-18 12:51:49 -0700456 if (i < 0 || ((instr->addr + instr->len) &
457 (erase_regions[i].erasesize - 1)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 return -EINVAL;
459 }
460
Adrian Hunterbb0eb212008-08-12 12:40:50 +0300461 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462
463 /* make a local copy of instr to avoid modifying the caller's struct */
464 erase = kmalloc(sizeof (struct erase_info), GFP_KERNEL);
465
466 if (!erase)
467 return -ENOMEM;
468
469 *erase = *instr;
470 length = instr->len;
471
472 /*
473 * find the subdevice where the to-be-erased area begins, adjust
474 * starting offset to be relative to the subdevice start
475 */
476 for (i = 0; i < concat->num_subdev; i++) {
477 subdev = concat->subdev[i];
478 if (subdev->size <= erase->addr) {
479 erase->addr -= subdev->size;
480 offset += subdev->size;
481 } else {
482 break;
483 }
484 }
485
486 /* must never happen since size limit has been verified above */
Eric Sesterhenn373ebfb2006-03-26 18:15:12 +0200487 BUG_ON(i >= concat->num_subdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
489 /* now do the erase: */
490 err = 0;
491 for (; length > 0; i++) {
492 /* loop for all subdevices affected by this request */
493 subdev = concat->subdev[i]; /* get current subdevice */
494
495 /* limit length to subdevice's size: */
496 if (erase->addr + length > subdev->size)
497 erase->len = subdev->size - erase->addr;
498 else
499 erase->len = length;
500
501 if (!(subdev->flags & MTD_WRITEABLE)) {
502 err = -EROFS;
503 break;
504 }
505 length -= erase->len;
506 if ((err = concat_dev_erase(subdev, erase))) {
507 /* sanity check: should never happen since
508 * block alignment has been checked above */
Eric Sesterhenn373ebfb2006-03-26 18:15:12 +0200509 BUG_ON(err == -EINVAL);
Adrian Hunterbb0eb212008-08-12 12:40:50 +0300510 if (erase->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 instr->fail_addr = erase->fail_addr + offset;
512 break;
513 }
514 /*
515 * erase->addr specifies the offset of the area to be
516 * erased *within the current subdevice*. It can be
517 * non-zero only the first time through this loop, i.e.
518 * for the first subdevice where blocks need to be erased.
519 * All the following erases must begin at the start of the
520 * current subdevice, i.e. at offset zero.
521 */
522 erase->addr = 0;
523 offset += subdev->size;
524 }
525 instr->state = erase->state;
526 kfree(erase);
527 if (err)
528 return err;
529
530 if (instr->callback)
531 instr->callback(instr);
532 return 0;
533}
534
Adrian Hunter69423d92008-12-10 13:37:21 +0000535static int concat_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536{
537 struct mtd_concat *concat = CONCAT(mtd);
538 int i, err = -EINVAL;
539
540 if ((len + ofs) > mtd->size)
541 return -EINVAL;
542
543 for (i = 0; i < concat->num_subdev; i++) {
544 struct mtd_info *subdev = concat->subdev[i];
Adrian Hunter69423d92008-12-10 13:37:21 +0000545 uint64_t size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546
547 if (ofs >= subdev->size) {
548 size = 0;
549 ofs -= subdev->size;
550 continue;
551 }
552 if (ofs + len > subdev->size)
553 size = subdev->size - ofs;
554 else
555 size = len;
556
Martin Krausee1d0fe32010-06-22 15:00:19 +0200557 if (subdev->lock) {
558 err = subdev->lock(subdev, ofs, size);
559 if (err)
560 break;
561 } else
562 err = -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563
564 len -= size;
565 if (len == 0)
566 break;
567
568 err = -EINVAL;
569 ofs = 0;
570 }
571
572 return err;
573}
574
Adrian Hunter69423d92008-12-10 13:37:21 +0000575static int concat_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576{
577 struct mtd_concat *concat = CONCAT(mtd);
578 int i, err = 0;
579
580 if ((len + ofs) > mtd->size)
581 return -EINVAL;
582
583 for (i = 0; i < concat->num_subdev; i++) {
584 struct mtd_info *subdev = concat->subdev[i];
Adrian Hunter69423d92008-12-10 13:37:21 +0000585 uint64_t size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586
587 if (ofs >= subdev->size) {
588 size = 0;
589 ofs -= subdev->size;
590 continue;
591 }
592 if (ofs + len > subdev->size)
593 size = subdev->size - ofs;
594 else
595 size = len;
596
Martin Krausee1d0fe32010-06-22 15:00:19 +0200597 if (subdev->unlock) {
598 err = subdev->unlock(subdev, ofs, size);
599 if (err)
600 break;
601 } else
602 err = -EOPNOTSUPP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
604 len -= size;
605 if (len == 0)
606 break;
607
608 err = -EINVAL;
609 ofs = 0;
610 }
611
612 return err;
613}
614
615static void concat_sync(struct mtd_info *mtd)
616{
617 struct mtd_concat *concat = CONCAT(mtd);
618 int i;
619
620 for (i = 0; i < concat->num_subdev; i++) {
621 struct mtd_info *subdev = concat->subdev[i];
622 subdev->sync(subdev);
623 }
624}
625
626static int concat_suspend(struct mtd_info *mtd)
627{
628 struct mtd_concat *concat = CONCAT(mtd);
629 int i, rc = 0;
630
631 for (i = 0; i < concat->num_subdev; i++) {
632 struct mtd_info *subdev = concat->subdev[i];
633 if ((rc = subdev->suspend(subdev)) < 0)
634 return rc;
635 }
636 return rc;
637}
638
639static void concat_resume(struct mtd_info *mtd)
640{
641 struct mtd_concat *concat = CONCAT(mtd);
642 int i;
643
644 for (i = 0; i < concat->num_subdev; i++) {
645 struct mtd_info *subdev = concat->subdev[i];
646 subdev->resume(subdev);
647 }
648}
649
Alexander Belyakove8d32932006-05-17 19:11:16 +0400650static int concat_block_isbad(struct mtd_info *mtd, loff_t ofs)
651{
652 struct mtd_concat *concat = CONCAT(mtd);
653 int i, res = 0;
654
655 if (!concat->subdev[0]->block_isbad)
656 return res;
657
658 if (ofs > mtd->size)
659 return -EINVAL;
660
661 for (i = 0; i < concat->num_subdev; i++) {
662 struct mtd_info *subdev = concat->subdev[i];
663
664 if (ofs >= subdev->size) {
665 ofs -= subdev->size;
666 continue;
667 }
668
669 res = subdev->block_isbad(subdev, ofs);
670 break;
671 }
672
673 return res;
674}
675
676static int concat_block_markbad(struct mtd_info *mtd, loff_t ofs)
677{
678 struct mtd_concat *concat = CONCAT(mtd);
679 int i, err = -EINVAL;
680
681 if (!concat->subdev[0]->block_markbad)
682 return 0;
683
684 if (ofs > mtd->size)
685 return -EINVAL;
686
687 for (i = 0; i < concat->num_subdev; i++) {
688 struct mtd_info *subdev = concat->subdev[i];
689
690 if (ofs >= subdev->size) {
691 ofs -= subdev->size;
692 continue;
693 }
694
695 err = subdev->block_markbad(subdev, ofs);
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200696 if (!err)
697 mtd->ecc_stats.badblocks++;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400698 break;
699 }
700
701 return err;
702}
703
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704/*
David Howells6e232cf2009-02-12 10:40:05 +0000705 * try to support NOMMU mmaps on concatenated devices
706 * - we don't support subdev spanning as we can't guarantee it'll work
707 */
708static unsigned long concat_get_unmapped_area(struct mtd_info *mtd,
709 unsigned long len,
710 unsigned long offset,
711 unsigned long flags)
712{
713 struct mtd_concat *concat = CONCAT(mtd);
714 int i;
715
716 for (i = 0; i < concat->num_subdev; i++) {
717 struct mtd_info *subdev = concat->subdev[i];
718
719 if (offset >= subdev->size) {
720 offset -= subdev->size;
721 continue;
722 }
723
724 /* we've found the subdev over which the mapping will reside */
725 if (offset + len > subdev->size)
726 return (unsigned long) -EINVAL;
727
728 if (subdev->get_unmapped_area)
729 return subdev->get_unmapped_area(subdev, len, offset,
730 flags);
731
732 break;
733 }
734
735 return (unsigned long) -ENOSYS;
736}
737
738/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 * This function constructs a virtual MTD device by concatenating
740 * num_devs MTD devices. A pointer to the new device object is
741 * stored to *new_dev upon success. This function does _not_
742 * register any devices: this is the caller's responsibility.
743 */
744struct mtd_info *mtd_concat_create(struct mtd_info *subdev[], /* subdevices to concatenate */
745 int num_devs, /* number of subdevices */
Kay Sievers160bbab2008-12-23 10:00:14 +0000746 const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747{ /* name for the new device */
748 int i;
749 size_t size;
750 struct mtd_concat *concat;
David Woodhouse26cdb672008-12-10 14:08:12 +0000751 uint32_t max_erasesize, curr_erasesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700752 int num_erase_region;
753
754 printk(KERN_NOTICE "Concatenating MTD devices:\n");
755 for (i = 0; i < num_devs; i++)
756 printk(KERN_NOTICE "(%d): \"%s\"\n", i, subdev[i]->name);
757 printk(KERN_NOTICE "into device \"%s\"\n", name);
758
759 /* allocate the device structure */
760 size = SIZEOF_STRUCT_MTD_CONCAT(num_devs);
Burman Yan95b93a02006-11-15 21:10:29 +0200761 concat = kzalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 if (!concat) {
763 printk
764 ("memory allocation error while creating concatenated device \"%s\"\n",
765 name);
766 return NULL;
767 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768 concat->subdev = (struct mtd_info **) (concat + 1);
769
770 /*
771 * Set up the new "super" device's MTD object structure, check for
772 * incompatibilites between the subdevices.
773 */
774 concat->mtd.type = subdev[0]->type;
775 concat->mtd.flags = subdev[0]->flags;
776 concat->mtd.size = subdev[0]->size;
777 concat->mtd.erasesize = subdev[0]->erasesize;
Joern Engel28318772006-05-22 23:18:05 +0200778 concat->mtd.writesize = subdev[0]->writesize;
Anatolij Gustschin7fa33ac2010-12-16 23:42:18 +0100779 concat->mtd.writebufsize = subdev[0]->writebufsize;
Chris Paulson-Ellisa2e1b832007-10-12 10:54:06 +0100780 concat->mtd.subpage_sft = subdev[0]->subpage_sft;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 concat->mtd.oobsize = subdev[0]->oobsize;
Vitaly Wool1f922672007-03-06 16:56:34 +0300782 concat->mtd.oobavail = subdev[0]->oobavail;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400783 if (subdev[0]->writev)
784 concat->mtd.writev = concat_writev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 if (subdev[0]->read_oob)
786 concat->mtd.read_oob = concat_read_oob;
787 if (subdev[0]->write_oob)
788 concat->mtd.write_oob = concat_write_oob;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400789 if (subdev[0]->block_isbad)
790 concat->mtd.block_isbad = concat_block_isbad;
791 if (subdev[0]->block_markbad)
792 concat->mtd.block_markbad = concat_block_markbad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200794 concat->mtd.ecc_stats.badblocks = subdev[0]->ecc_stats.badblocks;
795
David Howells6e232cf2009-02-12 10:40:05 +0000796 concat->mtd.backing_dev_info = subdev[0]->backing_dev_info;
797
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 concat->subdev[0] = subdev[0];
799
800 for (i = 1; i < num_devs; i++) {
801 if (concat->mtd.type != subdev[i]->type) {
802 kfree(concat);
803 printk("Incompatible device type on \"%s\"\n",
804 subdev[i]->name);
805 return NULL;
806 }
807 if (concat->mtd.flags != subdev[i]->flags) {
808 /*
809 * Expect all flags except MTD_WRITEABLE to be
810 * equal on all subdevices.
811 */
812 if ((concat->mtd.flags ^ subdev[i]->
813 flags) & ~MTD_WRITEABLE) {
814 kfree(concat);
815 printk("Incompatible device flags on \"%s\"\n",
816 subdev[i]->name);
817 return NULL;
818 } else
819 /* if writeable attribute differs,
820 make super device writeable */
821 concat->mtd.flags |=
822 subdev[i]->flags & MTD_WRITEABLE;
823 }
David Howells6e232cf2009-02-12 10:40:05 +0000824
825 /* only permit direct mapping if the BDIs are all the same
826 * - copy-mapping is still permitted
827 */
828 if (concat->mtd.backing_dev_info !=
829 subdev[i]->backing_dev_info)
830 concat->mtd.backing_dev_info =
831 &default_backing_dev_info;
832
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 concat->mtd.size += subdev[i]->size;
Thomas Gleixnerf1a28c02006-05-30 00:37:34 +0200834 concat->mtd.ecc_stats.badblocks +=
835 subdev[i]->ecc_stats.badblocks;
Joern Engel28318772006-05-22 23:18:05 +0200836 if (concat->mtd.writesize != subdev[i]->writesize ||
Thomas Gleixner29072b92006-09-28 15:38:36 +0200837 concat->mtd.subpage_sft != subdev[i]->subpage_sft ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 concat->mtd.oobsize != subdev[i]->oobsize ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 !concat->mtd.read_oob != !subdev[i]->read_oob ||
840 !concat->mtd.write_oob != !subdev[i]->write_oob) {
841 kfree(concat);
842 printk("Incompatible OOB or ECC data on \"%s\"\n",
843 subdev[i]->name);
844 return NULL;
845 }
846 concat->subdev[i] = subdev[i];
847
848 }
849
Thomas Gleixner5bd34c02006-05-27 22:16:10 +0200850 concat->mtd.ecclayout = subdev[0]->ecclayout;
Alexander Belyakove8d32932006-05-17 19:11:16 +0400851
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852 concat->num_subdev = num_devs;
853 concat->mtd.name = name;
854
Linus Torvalds1da177e2005-04-16 15:20:36 -0700855 concat->mtd.erase = concat_erase;
856 concat->mtd.read = concat_read;
857 concat->mtd.write = concat_write;
858 concat->mtd.sync = concat_sync;
859 concat->mtd.lock = concat_lock;
860 concat->mtd.unlock = concat_unlock;
861 concat->mtd.suspend = concat_suspend;
862 concat->mtd.resume = concat_resume;
David Howells6e232cf2009-02-12 10:40:05 +0000863 concat->mtd.get_unmapped_area = concat_get_unmapped_area;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700864
865 /*
866 * Combine the erase block size info of the subdevices:
867 *
868 * first, walk the map of the new device and see how
869 * many changes in erase size we have
870 */
871 max_erasesize = curr_erasesize = subdev[0]->erasesize;
872 num_erase_region = 1;
873 for (i = 0; i < num_devs; i++) {
874 if (subdev[i]->numeraseregions == 0) {
875 /* current subdevice has uniform erase size */
876 if (subdev[i]->erasesize != curr_erasesize) {
877 /* if it differs from the last subdevice's erase size, count it */
878 ++num_erase_region;
879 curr_erasesize = subdev[i]->erasesize;
880 if (curr_erasesize > max_erasesize)
881 max_erasesize = curr_erasesize;
882 }
883 } else {
884 /* current subdevice has variable erase size */
885 int j;
886 for (j = 0; j < subdev[i]->numeraseregions; j++) {
887
888 /* walk the list of erase regions, count any changes */
889 if (subdev[i]->eraseregions[j].erasesize !=
890 curr_erasesize) {
891 ++num_erase_region;
892 curr_erasesize =
893 subdev[i]->eraseregions[j].
894 erasesize;
895 if (curr_erasesize > max_erasesize)
896 max_erasesize = curr_erasesize;
897 }
898 }
899 }
900 }
901
902 if (num_erase_region == 1) {
903 /*
904 * All subdevices have the same uniform erase size.
905 * This is easy:
906 */
907 concat->mtd.erasesize = curr_erasesize;
908 concat->mtd.numeraseregions = 0;
909 } else {
Adrian Hunter69423d92008-12-10 13:37:21 +0000910 uint64_t tmp64;
911
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912 /*
913 * erase block size varies across the subdevices: allocate
914 * space to store the data describing the variable erase regions
915 */
916 struct mtd_erase_region_info *erase_region_p;
Adrian Hunter69423d92008-12-10 13:37:21 +0000917 uint64_t begin, position;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918
919 concat->mtd.erasesize = max_erasesize;
920 concat->mtd.numeraseregions = num_erase_region;
921 concat->mtd.eraseregions = erase_region_p =
922 kmalloc(num_erase_region *
923 sizeof (struct mtd_erase_region_info), GFP_KERNEL);
924 if (!erase_region_p) {
925 kfree(concat);
926 printk
927 ("memory allocation error while creating erase region list"
928 " for device \"%s\"\n", name);
929 return NULL;
930 }
931
932 /*
933 * walk the map of the new device once more and fill in
934 * in erase region info:
935 */
936 curr_erasesize = subdev[0]->erasesize;
937 begin = position = 0;
938 for (i = 0; i < num_devs; i++) {
939 if (subdev[i]->numeraseregions == 0) {
940 /* current subdevice has uniform erase size */
941 if (subdev[i]->erasesize != curr_erasesize) {
942 /*
943 * fill in an mtd_erase_region_info structure for the area
944 * we have walked so far:
945 */
946 erase_region_p->offset = begin;
947 erase_region_p->erasesize =
948 curr_erasesize;
Adrian Hunter69423d92008-12-10 13:37:21 +0000949 tmp64 = position - begin;
950 do_div(tmp64, curr_erasesize);
951 erase_region_p->numblocks = tmp64;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952 begin = position;
953
954 curr_erasesize = subdev[i]->erasesize;
955 ++erase_region_p;
956 }
957 position += subdev[i]->size;
958 } else {
959 /* current subdevice has variable erase size */
960 int j;
961 for (j = 0; j < subdev[i]->numeraseregions; j++) {
962 /* walk the list of erase regions, count any changes */
963 if (subdev[i]->eraseregions[j].
964 erasesize != curr_erasesize) {
965 erase_region_p->offset = begin;
966 erase_region_p->erasesize =
967 curr_erasesize;
Adrian Hunter69423d92008-12-10 13:37:21 +0000968 tmp64 = position - begin;
969 do_div(tmp64, curr_erasesize);
970 erase_region_p->numblocks = tmp64;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971 begin = position;
972
973 curr_erasesize =
974 subdev[i]->eraseregions[j].
975 erasesize;
976 ++erase_region_p;
977 }
978 position +=
979 subdev[i]->eraseregions[j].
Adrian Hunter69423d92008-12-10 13:37:21 +0000980 numblocks * (uint64_t)curr_erasesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 }
982 }
983 }
984 /* Now write the final entry */
985 erase_region_p->offset = begin;
986 erase_region_p->erasesize = curr_erasesize;
Adrian Hunter69423d92008-12-10 13:37:21 +0000987 tmp64 = position - begin;
988 do_div(tmp64, curr_erasesize);
989 erase_region_p->numblocks = tmp64;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700990 }
991
992 return &concat->mtd;
993}
994
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000995/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 * This function destroys an MTD object obtained from concat_mtd_devs()
997 */
998
999void mtd_concat_destroy(struct mtd_info *mtd)
1000{
1001 struct mtd_concat *concat = CONCAT(mtd);
1002 if (concat->mtd.numeraseregions)
1003 kfree(concat->mtd.eraseregions);
1004 kfree(concat);
1005}
1006
1007EXPORT_SYMBOL(mtd_concat_create);
1008EXPORT_SYMBOL(mtd_concat_destroy);
1009
1010MODULE_LICENSE("GPL");
1011MODULE_AUTHOR("Robert Kaiser <rkaiser@sysgo.de>");
1012MODULE_DESCRIPTION("Generic support for concatenating of MTD devices");