xref: /linux/include/linux/mtd/mtd.h (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org> et al.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  *
18  */
19 
20 #ifndef __MTD_MTD_H__
21 #define __MTD_MTD_H__
22 
23 #include <linux/types.h>
24 #include <linux/uio.h>
25 #include <linux/notifier.h>
26 #include <linux/device.h>
27 
28 #include <mtd/mtd-abi.h>
29 
30 #include <asm/div64.h>
31 
32 #define MTD_CHAR_MAJOR 90
33 #define MTD_BLOCK_MAJOR 31
34 
35 #define MTD_ERASE_PENDING	0x01
36 #define MTD_ERASING		0x02
37 #define MTD_ERASE_SUSPEND	0x04
38 #define MTD_ERASE_DONE		0x08
39 #define MTD_ERASE_FAILED	0x10
40 
41 #define MTD_FAIL_ADDR_UNKNOWN -1LL
42 
43 /*
44  * If the erase fails, fail_addr might indicate exactly which block failed. If
45  * fail_addr = MTD_FAIL_ADDR_UNKNOWN, the failure was not at the device level
46  * or was not specific to any particular block.
47  */
48 struct erase_info {
49 	struct mtd_info *mtd;
50 	uint64_t addr;
51 	uint64_t len;
52 	uint64_t fail_addr;
53 	u_long time;
54 	u_long retries;
55 	unsigned dev;
56 	unsigned cell;
57 	void (*callback) (struct erase_info *self);
58 	u_long priv;
59 	u_char state;
60 	struct erase_info *next;
61 };
62 
63 struct mtd_erase_region_info {
64 	uint64_t offset;		/* At which this region starts, from the beginning of the MTD */
65 	uint32_t erasesize;		/* For this region */
66 	uint32_t numblocks;		/* Number of blocks of erasesize in this region */
67 	unsigned long *lockmap;		/* If keeping bitmap of locks */
68 };
69 
70 /**
71  * struct mtd_oob_ops - oob operation operands
72  * @mode:	operation mode
73  *
74  * @len:	number of data bytes to write/read
75  *
76  * @retlen:	number of data bytes written/read
77  *
78  * @ooblen:	number of oob bytes to write/read
79  * @oobretlen:	number of oob bytes written/read
80  * @ooboffs:	offset of oob data in the oob area (only relevant when
81  *		mode = MTD_OPS_PLACE_OOB or MTD_OPS_RAW)
82  * @datbuf:	data buffer - if NULL only oob data are read/written
83  * @oobbuf:	oob data buffer
84  *
85  * Note, it is allowed to read more than one OOB area at one go, but not write.
86  * The interface assumes that the OOB write requests program only one page's
87  * OOB area.
88  */
89 struct mtd_oob_ops {
90 	unsigned int	mode;
91 	size_t		len;
92 	size_t		retlen;
93 	size_t		ooblen;
94 	size_t		oobretlen;
95 	uint32_t	ooboffs;
96 	uint8_t		*datbuf;
97 	uint8_t		*oobbuf;
98 };
99 
100 #define MTD_MAX_OOBFREE_ENTRIES_LARGE	32
101 #define MTD_MAX_ECCPOS_ENTRIES_LARGE	448
102 /*
103  * Internal ECC layout control structure. For historical reasons, there is a
104  * similar, smaller struct nand_ecclayout_user (in mtd-abi.h) that is retained
105  * for export to user-space via the ECCGETLAYOUT ioctl.
106  * nand_ecclayout should be expandable in the future simply by the above macros.
107  */
108 struct nand_ecclayout {
109 	__u32 eccbytes;
110 	__u32 eccpos[MTD_MAX_ECCPOS_ENTRIES_LARGE];
111 	__u32 oobavail;
112 	struct nand_oobfree oobfree[MTD_MAX_OOBFREE_ENTRIES_LARGE];
113 };
114 
115 struct module;	/* only needed for owner field in mtd_info */
116 
117 struct mtd_info {
118 	u_char type;
119 	uint32_t flags;
120 	uint64_t size;	 // Total size of the MTD
121 
122 	/* "Major" erase size for the device. Naïve users may take this
123 	 * to be the only erase size available, or may use the more detailed
124 	 * information below if they desire
125 	 */
126 	uint32_t erasesize;
127 	/* Minimal writable flash unit size. In case of NOR flash it is 1 (even
128 	 * though individual bits can be cleared), in case of NAND flash it is
129 	 * one NAND page (or half, or one-fourths of it), in case of ECC-ed NOR
130 	 * it is of ECC block size, etc. It is illegal to have writesize = 0.
131 	 * Any driver registering a struct mtd_info must ensure a writesize of
132 	 * 1 or larger.
133 	 */
134 	uint32_t writesize;
135 
136 	/*
137 	 * Size of the write buffer used by the MTD. MTD devices having a write
138 	 * buffer can write multiple writesize chunks at a time. E.g. while
139 	 * writing 4 * writesize bytes to a device with 2 * writesize bytes
140 	 * buffer the MTD driver can (but doesn't have to) do 2 writesize
141 	 * operations, but not 4. Currently, all NANDs have writebufsize
142 	 * equivalent to writesize (NAND page size). Some NOR flashes do have
143 	 * writebufsize greater than writesize.
144 	 */
145 	uint32_t writebufsize;
146 
147 	uint32_t oobsize;   // Amount of OOB data per block (e.g. 16)
148 	uint32_t oobavail;  // Available OOB bytes per block
149 
150 	/*
151 	 * If erasesize is a power of 2 then the shift is stored in
152 	 * erasesize_shift otherwise erasesize_shift is zero. Ditto writesize.
153 	 */
154 	unsigned int erasesize_shift;
155 	unsigned int writesize_shift;
156 	/* Masks based on erasesize_shift and writesize_shift */
157 	unsigned int erasesize_mask;
158 	unsigned int writesize_mask;
159 
160 	// Kernel-only stuff starts here.
161 	const char *name;
162 	int index;
163 
164 	/* ECC layout structure pointer - read only! */
165 	struct nand_ecclayout *ecclayout;
166 
167 	/* Data for variable erase regions. If numeraseregions is zero,
168 	 * it means that the whole device has erasesize as given above.
169 	 */
170 	int numeraseregions;
171 	struct mtd_erase_region_info *eraseregions;
172 
173 	/*
174 	 * Do not call via these pointers, use corresponding mtd_*()
175 	 * wrappers instead.
176 	 */
177 	int (*erase) (struct mtd_info *mtd, struct erase_info *instr);
178 	int (*point) (struct mtd_info *mtd, loff_t from, size_t len,
179 		      size_t *retlen, void **virt, resource_size_t *phys);
180 	void (*unpoint) (struct mtd_info *mtd, loff_t from, size_t len);
181 	unsigned long (*get_unmapped_area) (struct mtd_info *mtd,
182 					    unsigned long len,
183 					    unsigned long offset,
184 					    unsigned long flags);
185 	int (*read) (struct mtd_info *mtd, loff_t from, size_t len,
186 		     size_t *retlen, u_char *buf);
187 	int (*write) (struct mtd_info *mtd, loff_t to, size_t len,
188 		      size_t *retlen, const u_char *buf);
189 	int (*panic_write) (struct mtd_info *mtd, loff_t to, size_t len,
190 			    size_t *retlen, const u_char *buf);
191 	int (*read_oob) (struct mtd_info *mtd, loff_t from,
192 			 struct mtd_oob_ops *ops);
193 	int (*write_oob) (struct mtd_info *mtd, loff_t to,
194 			  struct mtd_oob_ops *ops);
195 	int (*get_fact_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
196 				   size_t len);
197 	int (*read_fact_prot_reg) (struct mtd_info *mtd, loff_t from,
198 				   size_t len, size_t *retlen, u_char *buf);
199 	int (*get_user_prot_info) (struct mtd_info *mtd, struct otp_info *buf,
200 				   size_t len);
201 	int (*read_user_prot_reg) (struct mtd_info *mtd, loff_t from,
202 				   size_t len, size_t *retlen, u_char *buf);
203 	int (*write_user_prot_reg) (struct mtd_info *mtd, loff_t to, size_t len,
204 				    size_t *retlen, u_char *buf);
205 	int (*lock_user_prot_reg) (struct mtd_info *mtd, loff_t from,
206 				   size_t len);
207 	int (*writev) (struct mtd_info *mtd, const struct kvec *vecs,
208 			unsigned long count, loff_t to, size_t *retlen);
209 	void (*sync) (struct mtd_info *mtd);
210 	int (*lock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
211 	int (*unlock) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
212 	int (*is_locked) (struct mtd_info *mtd, loff_t ofs, uint64_t len);
213 	int (*block_isbad) (struct mtd_info *mtd, loff_t ofs);
214 	int (*block_markbad) (struct mtd_info *mtd, loff_t ofs);
215 	int (*suspend) (struct mtd_info *mtd);
216 	void (*resume) (struct mtd_info *mtd);
217 	/*
218 	 * If the driver is something smart, like UBI, it may need to maintain
219 	 * its own reference counting. The below functions are only for driver.
220 	 */
221 	int (*get_device) (struct mtd_info *mtd);
222 	void (*put_device) (struct mtd_info *mtd);
223 
224 	/* Backing device capabilities for this device
225 	 * - provides mmap capabilities
226 	 */
227 	struct backing_dev_info *backing_dev_info;
228 
229 	struct notifier_block reboot_notifier;  /* default mode before reboot */
230 
231 	/* ECC status information */
232 	struct mtd_ecc_stats ecc_stats;
233 	/* Subpage shift (NAND) */
234 	int subpage_sft;
235 
236 	void *priv;
237 
238 	struct module *owner;
239 	struct device dev;
240 	int usecount;
241 };
242 
243 /*
244  * Erase is an asynchronous operation.  Device drivers are supposed
245  * to call instr->callback() whenever the operation completes, even
246  * if it completes with a failure.
247  * Callers are supposed to pass a callback function and wait for it
248  * to be called before writing to the block.
249  */
250 static inline int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
251 {
252 	return mtd->erase(mtd, instr);
253 }
254 
255 /*
256  * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
257  */
258 static inline int mtd_point(struct mtd_info *mtd, loff_t from, size_t len,
259 			    size_t *retlen, void **virt, resource_size_t *phys)
260 {
261 	*retlen = 0;
262 	if (!mtd->point)
263 		return -EOPNOTSUPP;
264 	return mtd->point(mtd, from, len, retlen, virt, phys);
265 }
266 
267 /* We probably shouldn't allow XIP if the unpoint isn't a NULL */
268 static inline void mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
269 {
270 	return mtd->unpoint(mtd, from, len);
271 }
272 
273 /*
274  * Allow NOMMU mmap() to directly map the device (if not NULL)
275  * - return the address to which the offset maps
276  * - return -ENOSYS to indicate refusal to do the mapping
277  */
278 static inline unsigned long mtd_get_unmapped_area(struct mtd_info *mtd,
279 						  unsigned long len,
280 						  unsigned long offset,
281 						  unsigned long flags)
282 {
283 	if (!mtd->get_unmapped_area)
284 		return -EOPNOTSUPP;
285 	return mtd->get_unmapped_area(mtd, len, offset, flags);
286 }
287 
288 static inline int mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
289 			   size_t *retlen, u_char *buf)
290 {
291 	return mtd->read(mtd, from, len, retlen, buf);
292 }
293 
294 static inline int mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
295 			    size_t *retlen, const u_char *buf)
296 {
297 	*retlen = 0;
298 	if (!mtd->write)
299 		return -EROFS;
300 	return mtd->write(mtd, to, len, retlen, buf);
301 }
302 
303 /*
304  * In blackbox flight recorder like scenarios we want to make successful writes
305  * in interrupt context. panic_write() is only intended to be called when its
306  * known the kernel is about to panic and we need the write to succeed. Since
307  * the kernel is not going to be running for much longer, this function can
308  * break locks and delay to ensure the write succeeds (but not sleep).
309  */
310 static inline int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
311 				  size_t *retlen, const u_char *buf)
312 {
313 	*retlen = 0;
314 	if (!mtd->panic_write)
315 		return -EOPNOTSUPP;
316 	return mtd->panic_write(mtd, to, len, retlen, buf);
317 }
318 
319 static inline int mtd_read_oob(struct mtd_info *mtd, loff_t from,
320 			       struct mtd_oob_ops *ops)
321 {
322 	ops->retlen = ops->oobretlen = 0;
323 	if (!mtd->read_oob)
324 		return -EOPNOTSUPP;
325 	return mtd->read_oob(mtd, from, ops);
326 }
327 
328 static inline int mtd_write_oob(struct mtd_info *mtd, loff_t to,
329 				struct mtd_oob_ops *ops)
330 {
331 	ops->retlen = ops->oobretlen = 0;
332 	if (!mtd->write_oob)
333 		return -EOPNOTSUPP;
334 	return mtd->write_oob(mtd, to, ops);
335 }
336 
337 /*
338  * Method to access the protection register area, present in some flash
339  * devices. The user data is one time programmable but the factory data is read
340  * only.
341  */
342 static inline int mtd_get_fact_prot_info(struct mtd_info *mtd,
343 					 struct otp_info *buf, size_t len)
344 {
345 	if (!mtd->get_fact_prot_info)
346 		return -EOPNOTSUPP;
347 	return mtd->get_fact_prot_info(mtd, buf, len);
348 }
349 
350 static inline int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
351 					 size_t len, size_t *retlen,
352 					 u_char *buf)
353 {
354 	*retlen = 0;
355 	if (!mtd->read_fact_prot_reg)
356 		return -EOPNOTSUPP;
357 	return mtd->read_fact_prot_reg(mtd, from, len, retlen, buf);
358 }
359 
360 static inline int mtd_get_user_prot_info(struct mtd_info *mtd,
361 					 struct otp_info *buf,
362 					 size_t len)
363 {
364 	if (!mtd->get_user_prot_info)
365 		return -EOPNOTSUPP;
366 	return mtd->get_user_prot_info(mtd, buf, len);
367 }
368 
369 static inline int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
370 					 size_t len, size_t *retlen,
371 					 u_char *buf)
372 {
373 	*retlen = 0;
374 	if (!mtd->read_user_prot_reg)
375 		return -EOPNOTSUPP;
376 	return mtd->read_user_prot_reg(mtd, from, len, retlen, buf);
377 }
378 
379 static inline int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to,
380 					  size_t len, size_t *retlen,
381 					  u_char *buf)
382 {
383 	*retlen = 0;
384 	if (!mtd->write_user_prot_reg)
385 		return -EOPNOTSUPP;
386 	return mtd->write_user_prot_reg(mtd, to, len, retlen, buf);
387 }
388 
389 static inline int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
390 					 size_t len)
391 {
392 	if (!mtd->lock_user_prot_reg)
393 		return -EOPNOTSUPP;
394 	return mtd->lock_user_prot_reg(mtd, from, len);
395 }
396 
397 int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
398 	       unsigned long count, loff_t to, size_t *retlen);
399 
400 static inline void mtd_sync(struct mtd_info *mtd)
401 {
402 	if (mtd->sync)
403 		mtd->sync(mtd);
404 }
405 
406 /* Chip-supported device locking */
407 static inline int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
408 {
409 	if (!mtd->lock)
410 		return -EOPNOTSUPP;
411 	return mtd->lock(mtd, ofs, len);
412 }
413 
414 static inline int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
415 {
416 	if (!mtd->unlock)
417 		return -EOPNOTSUPP;
418 	return mtd->unlock(mtd, ofs, len);
419 }
420 
421 static inline int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
422 {
423 	if (!mtd->is_locked)
424 		return -EOPNOTSUPP;
425 	return mtd->is_locked(mtd, ofs, len);
426 }
427 
428 static inline int mtd_suspend(struct mtd_info *mtd)
429 {
430 	if (!mtd->suspend)
431 		return -EOPNOTSUPP;
432 	return mtd->suspend(mtd);
433 }
434 
435 static inline void mtd_resume(struct mtd_info *mtd)
436 {
437 	if (mtd->resume)
438 		mtd->resume(mtd);
439 }
440 
441 static inline int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
442 {
443 	if (!mtd->block_isbad)
444 		return -EOPNOTSUPP;
445 	return mtd->block_isbad(mtd, ofs);
446 }
447 
448 static inline int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
449 {
450 	if (!mtd->block_markbad)
451 		return -EOPNOTSUPP;
452 	return mtd->block_markbad(mtd, ofs);
453 }
454 
455 static inline uint32_t mtd_div_by_eb(uint64_t sz, struct mtd_info *mtd)
456 {
457 	if (mtd->erasesize_shift)
458 		return sz >> mtd->erasesize_shift;
459 	do_div(sz, mtd->erasesize);
460 	return sz;
461 }
462 
463 static inline uint32_t mtd_mod_by_eb(uint64_t sz, struct mtd_info *mtd)
464 {
465 	if (mtd->erasesize_shift)
466 		return sz & mtd->erasesize_mask;
467 	return do_div(sz, mtd->erasesize);
468 }
469 
470 static inline uint32_t mtd_div_by_ws(uint64_t sz, struct mtd_info *mtd)
471 {
472 	if (mtd->writesize_shift)
473 		return sz >> mtd->writesize_shift;
474 	do_div(sz, mtd->writesize);
475 	return sz;
476 }
477 
478 static inline uint32_t mtd_mod_by_ws(uint64_t sz, struct mtd_info *mtd)
479 {
480 	if (mtd->writesize_shift)
481 		return sz & mtd->writesize_mask;
482 	return do_div(sz, mtd->writesize);
483 }
484 
485 static inline int mtd_has_oob(const struct mtd_info *mtd)
486 {
487 	return mtd->read_oob && mtd->write_oob;
488 }
489 
490 static inline int mtd_can_have_bb(const struct mtd_info *mtd)
491 {
492 	return !!mtd->block_isbad;
493 }
494 
495 	/* Kernel-side ioctl definitions */
496 
497 struct mtd_partition;
498 struct mtd_part_parser_data;
499 
500 extern int mtd_device_parse_register(struct mtd_info *mtd,
501 			      const char **part_probe_types,
502 			      struct mtd_part_parser_data *parser_data,
503 			      const struct mtd_partition *defparts,
504 			      int defnr_parts);
505 #define mtd_device_register(master, parts, nr_parts)	\
506 	mtd_device_parse_register(master, NULL, NULL, parts, nr_parts)
507 extern int mtd_device_unregister(struct mtd_info *master);
508 extern struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num);
509 extern int __get_mtd_device(struct mtd_info *mtd);
510 extern void __put_mtd_device(struct mtd_info *mtd);
511 extern struct mtd_info *get_mtd_device_nm(const char *name);
512 extern void put_mtd_device(struct mtd_info *mtd);
513 
514 
515 struct mtd_notifier {
516 	void (*add)(struct mtd_info *mtd);
517 	void (*remove)(struct mtd_info *mtd);
518 	struct list_head list;
519 };
520 
521 
522 extern void register_mtd_user (struct mtd_notifier *new);
523 extern int unregister_mtd_user (struct mtd_notifier *old);
524 void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size);
525 
526 void mtd_erase_callback(struct erase_info *instr);
527 
528 static inline int mtd_is_bitflip(int err) {
529 	return err == -EUCLEAN;
530 }
531 
532 static inline int mtd_is_eccerr(int err) {
533 	return err == -EBADMSG;
534 }
535 
536 static inline int mtd_is_bitflip_or_eccerr(int err) {
537 	return mtd_is_bitflip(err) || mtd_is_eccerr(err);
538 }
539 
540 #endif /* __MTD_MTD_H__ */
541