1/*
2 * Copyright �� 1999-2010 David Woodhouse <dwmw2@infradead.org>
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#include <linux/device.h>
21#include <linux/fs.h>
22#include <linux/mm.h>
23#include <linux/err.h>
24#include <linux/init.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/sched.h>
29#include <linux/mutex.h>
30#include <linux/backing-dev.h>
31#include <linux/compat.h>
32#include <linux/mount.h>
33#include <linux/blkpg.h>
34#include <linux/magic.h>
35#include <linux/major.h>
36#include <linux/mtd/mtd.h>
37#include <linux/mtd/partitions.h>
38#include <linux/mtd/map.h>
39
40#include <asm/uaccess.h>
41
42#include "mtdcore.h"
43
44static DEFINE_MUTEX(mtd_mutex);
45
46/*
47 * Data structure to hold the pointer to the mtd device as well
48 * as mode information of various use cases.
49 */
50struct mtd_file_info {
51	struct mtd_info *mtd;
52	enum mtd_file_modes mode;
53};
54
55static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
56{
57	struct mtd_file_info *mfi = file->private_data;
58	return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
59}
60
61static int mtdchar_open(struct inode *inode, struct file *file)
62{
63	int minor = iminor(inode);
64	int devnum = minor >> 1;
65	int ret = 0;
66	struct mtd_info *mtd;
67	struct mtd_file_info *mfi;
68
69	pr_debug("MTD_open\n");
70
71	/* You can't open the RO devices RW */
72	if ((file->f_mode & FMODE_WRITE) && (minor & 1))
73		return -EACCES;
74
75	mutex_lock(&mtd_mutex);
76	mtd = get_mtd_device(NULL, devnum);
77
78	if (IS_ERR(mtd)) {
79		ret = PTR_ERR(mtd);
80		goto out;
81	}
82
83	if (mtd->type == MTD_ABSENT) {
84		ret = -ENODEV;
85		goto out1;
86	}
87
88	/* You can't open it RW if it's not a writeable device */
89	if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
90		ret = -EACCES;
91		goto out1;
92	}
93
94	mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
95	if (!mfi) {
96		ret = -ENOMEM;
97		goto out1;
98	}
99	mfi->mtd = mtd;
100	file->private_data = mfi;
101	mutex_unlock(&mtd_mutex);
102	return 0;
103
104out1:
105	put_mtd_device(mtd);
106out:
107	mutex_unlock(&mtd_mutex);
108	return ret;
109} /* mtdchar_open */
110
111/*====================================================================*/
112
113static int mtdchar_close(struct inode *inode, struct file *file)
114{
115	struct mtd_file_info *mfi = file->private_data;
116	struct mtd_info *mtd = mfi->mtd;
117
118	pr_debug("MTD_close\n");
119
120	/* Only sync if opened RW */
121	if ((file->f_mode & FMODE_WRITE))
122		mtd_sync(mtd);
123
124	put_mtd_device(mtd);
125	file->private_data = NULL;
126	kfree(mfi);
127
128	return 0;
129} /* mtdchar_close */
130
131/* Back in June 2001, dwmw2 wrote:
132 *
133 *   FIXME: This _really_ needs to die. In 2.5, we should lock the
134 *   userspace buffer down and use it directly with readv/writev.
135 *
136 * The implementation below, using mtd_kmalloc_up_to, mitigates
137 * allocation failures when the system is under low-memory situations
138 * or if memory is highly fragmented at the cost of reducing the
139 * performance of the requested transfer due to a smaller buffer size.
140 *
141 * A more complex but more memory-efficient implementation based on
142 * get_user_pages and iovecs to cover extents of those pages is a
143 * longer-term goal, as intimated by dwmw2 above. However, for the
144 * write case, this requires yet more complex head and tail transfer
145 * handling when those head and tail offsets and sizes are such that
146 * alignment requirements are not met in the NAND subdriver.
147 */
148
149static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
150			loff_t *ppos)
151{
152	struct mtd_file_info *mfi = file->private_data;
153	struct mtd_info *mtd = mfi->mtd;
154	size_t retlen;
155	size_t total_retlen=0;
156	int ret=0;
157	int len;
158	size_t size = count;
159	char *kbuf;
160
161	pr_debug("MTD_read\n");
162
163	if (*ppos + count > mtd->size)
164		count = mtd->size - *ppos;
165
166	if (!count)
167		return 0;
168
169	kbuf = mtd_kmalloc_up_to(mtd, &size);
170	if (!kbuf)
171		return -ENOMEM;
172
173	while (count) {
174		len = min_t(size_t, count, size);
175
176		switch (mfi->mode) {
177		case MTD_FILE_MODE_OTP_FACTORY:
178			ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
179						     &retlen, kbuf);
180			break;
181		case MTD_FILE_MODE_OTP_USER:
182			ret = mtd_read_user_prot_reg(mtd, *ppos, len,
183						     &retlen, kbuf);
184			break;
185		case MTD_FILE_MODE_RAW:
186		{
187			struct mtd_oob_ops ops;
188
189			ops.mode = MTD_OPS_RAW;
190			ops.datbuf = kbuf;
191			ops.oobbuf = NULL;
192			ops.len = len;
193
194			ret = mtd_read_oob(mtd, *ppos, &ops);
195			retlen = ops.retlen;
196			break;
197		}
198		default:
199			ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
200		}
201		/* Nand returns -EBADMSG on ECC errors, but it returns
202		 * the data. For our userspace tools it is important
203		 * to dump areas with ECC errors!
204		 * For kernel internal usage it also might return -EUCLEAN
205		 * to signal the caller that a bitflip has occurred and has
206		 * been corrected by the ECC algorithm.
207		 * Userspace software which accesses NAND this way
208		 * must be aware of the fact that it deals with NAND
209		 */
210		if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
211			*ppos += retlen;
212			if (copy_to_user(buf, kbuf, retlen)) {
213				kfree(kbuf);
214				return -EFAULT;
215			}
216			else
217				total_retlen += retlen;
218
219			count -= retlen;
220			buf += retlen;
221			if (retlen == 0)
222				count = 0;
223		}
224		else {
225			kfree(kbuf);
226			return ret;
227		}
228
229	}
230
231	kfree(kbuf);
232	return total_retlen;
233} /* mtdchar_read */
234
235static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
236			loff_t *ppos)
237{
238	struct mtd_file_info *mfi = file->private_data;
239	struct mtd_info *mtd = mfi->mtd;
240	size_t size = count;
241	char *kbuf;
242	size_t retlen;
243	size_t total_retlen=0;
244	int ret=0;
245	int len;
246
247	pr_debug("MTD_write\n");
248
249	if (*ppos == mtd->size)
250		return -ENOSPC;
251
252	if (*ppos + count > mtd->size)
253		count = mtd->size - *ppos;
254
255	if (!count)
256		return 0;
257
258	kbuf = mtd_kmalloc_up_to(mtd, &size);
259	if (!kbuf)
260		return -ENOMEM;
261
262	while (count) {
263		len = min_t(size_t, count, size);
264
265		if (copy_from_user(kbuf, buf, len)) {
266			kfree(kbuf);
267			return -EFAULT;
268		}
269
270		switch (mfi->mode) {
271		case MTD_FILE_MODE_OTP_FACTORY:
272			ret = -EROFS;
273			break;
274		case MTD_FILE_MODE_OTP_USER:
275			ret = mtd_write_user_prot_reg(mtd, *ppos, len,
276						      &retlen, kbuf);
277			break;
278
279		case MTD_FILE_MODE_RAW:
280		{
281			struct mtd_oob_ops ops;
282
283			ops.mode = MTD_OPS_RAW;
284			ops.datbuf = kbuf;
285			ops.oobbuf = NULL;
286			ops.ooboffs = 0;
287			ops.len = len;
288
289			ret = mtd_write_oob(mtd, *ppos, &ops);
290			retlen = ops.retlen;
291			break;
292		}
293
294		default:
295			ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
296		}
297
298		/*
299		 * Return -ENOSPC only if no data could be written at all.
300		 * Otherwise just return the number of bytes that actually
301		 * have been written.
302		 */
303		if ((ret == -ENOSPC) && (total_retlen))
304			break;
305
306		if (!ret) {
307			*ppos += retlen;
308			total_retlen += retlen;
309			count -= retlen;
310			buf += retlen;
311		}
312		else {
313			kfree(kbuf);
314			return ret;
315		}
316	}
317
318	kfree(kbuf);
319	return total_retlen;
320} /* mtdchar_write */
321
322/*======================================================================
323
324    IOCTL calls for getting device parameters.
325
326======================================================================*/
327static void mtdchar_erase_callback (struct erase_info *instr)
328{
329	wake_up((wait_queue_head_t *)instr->priv);
330}
331
332static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
333{
334	struct mtd_info *mtd = mfi->mtd;
335	size_t retlen;
336
337	switch (mode) {
338	case MTD_OTP_FACTORY:
339		if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
340				-EOPNOTSUPP)
341			return -EOPNOTSUPP;
342
343		mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
344		break;
345	case MTD_OTP_USER:
346		if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
347				-EOPNOTSUPP)
348			return -EOPNOTSUPP;
349
350		mfi->mode = MTD_FILE_MODE_OTP_USER;
351		break;
352	case MTD_OTP_OFF:
353		mfi->mode = MTD_FILE_MODE_NORMAL;
354		break;
355	default:
356		return -EINVAL;
357	}
358
359	return 0;
360}
361
362static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
363	uint64_t start, uint32_t length, void __user *ptr,
364	uint32_t __user *retp)
365{
366	struct mtd_file_info *mfi = file->private_data;
367	struct mtd_oob_ops ops;
368	uint32_t retlen;
369	int ret = 0;
370
371	if (!(file->f_mode & FMODE_WRITE))
372		return -EPERM;
373
374	if (length > 4096)
375		return -EINVAL;
376
377	if (!mtd->_write_oob)
378		ret = -EOPNOTSUPP;
379	else
380		ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
381
382	if (ret)
383		return ret;
384
385	ops.ooblen = length;
386	ops.ooboffs = start & (mtd->writesize - 1);
387	ops.datbuf = NULL;
388	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
389		MTD_OPS_PLACE_OOB;
390
391	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
392		return -EINVAL;
393
394	ops.oobbuf = memdup_user(ptr, length);
395	if (IS_ERR(ops.oobbuf))
396		return PTR_ERR(ops.oobbuf);
397
398	start &= ~((uint64_t)mtd->writesize - 1);
399	ret = mtd_write_oob(mtd, start, &ops);
400
401	if (ops.oobretlen > 0xFFFFFFFFU)
402		ret = -EOVERFLOW;
403	retlen = ops.oobretlen;
404	if (copy_to_user(retp, &retlen, sizeof(length)))
405		ret = -EFAULT;
406
407	kfree(ops.oobbuf);
408	return ret;
409}
410
411static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
412	uint64_t start, uint32_t length, void __user *ptr,
413	uint32_t __user *retp)
414{
415	struct mtd_file_info *mfi = file->private_data;
416	struct mtd_oob_ops ops;
417	int ret = 0;
418
419	if (length > 4096)
420		return -EINVAL;
421
422	if (!access_ok(VERIFY_WRITE, ptr, length))
423		return -EFAULT;
424
425	ops.ooblen = length;
426	ops.ooboffs = start & (mtd->writesize - 1);
427	ops.datbuf = NULL;
428	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
429		MTD_OPS_PLACE_OOB;
430
431	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
432		return -EINVAL;
433
434	ops.oobbuf = kmalloc(length, GFP_KERNEL);
435	if (!ops.oobbuf)
436		return -ENOMEM;
437
438	start &= ~((uint64_t)mtd->writesize - 1);
439	ret = mtd_read_oob(mtd, start, &ops);
440
441	if (put_user(ops.oobretlen, retp))
442		ret = -EFAULT;
443	else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
444					    ops.oobretlen))
445		ret = -EFAULT;
446
447	kfree(ops.oobbuf);
448
449	/*
450	 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
451	 * data. For our userspace tools it is important to dump areas
452	 * with ECC errors!
453	 * For kernel internal usage it also might return -EUCLEAN
454	 * to signal the caller that a bitflip has occured and has
455	 * been corrected by the ECC algorithm.
456	 *
457	 * Note: currently the standard NAND function, nand_read_oob_std,
458	 * does not calculate ECC for the OOB area, so do not rely on
459	 * this behavior unless you have replaced it with your own.
460	 */
461	if (mtd_is_bitflip_or_eccerr(ret))
462		return 0;
463
464	return ret;
465}
466
467/*
468 * Copies (and truncates, if necessary) data from the larger struct,
469 * nand_ecclayout, to the smaller, deprecated layout struct,
470 * nand_ecclayout_user. This is necessary only to support the deprecated
471 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
472 * nand_ecclayout flexibly (i.e. the struct may change size in new
473 * releases without requiring major rewrites).
474 */
475static int shrink_ecclayout(const struct nand_ecclayout *from,
476		struct nand_ecclayout_user *to)
477{
478	int i;
479
480	if (!from || !to)
481		return -EINVAL;
482
483	memset(to, 0, sizeof(*to));
484
485	to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
486	for (i = 0; i < to->eccbytes; i++)
487		to->eccpos[i] = from->eccpos[i];
488
489	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
490		if (from->oobfree[i].length == 0 &&
491				from->oobfree[i].offset == 0)
492			break;
493		to->oobavail += from->oobfree[i].length;
494		to->oobfree[i] = from->oobfree[i];
495	}
496
497	return 0;
498}
499
500static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
501			       struct blkpg_ioctl_arg *arg)
502{
503	struct blkpg_partition p;
504
505	if (!capable(CAP_SYS_ADMIN))
506		return -EPERM;
507
508	if (copy_from_user(&p, arg->data, sizeof(p)))
509		return -EFAULT;
510
511	switch (arg->op) {
512	case BLKPG_ADD_PARTITION:
513
514		/* Only master mtd device must be used to add partitions */
515		if (mtd_is_partition(mtd))
516			return -EINVAL;
517
518		/* Sanitize user input */
519		p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
520
521		return mtd_add_partition(mtd, p.devname, p.start, p.length);
522
523	case BLKPG_DEL_PARTITION:
524
525		if (p.pno < 0)
526			return -EINVAL;
527
528		return mtd_del_partition(mtd, p.pno);
529
530	default:
531		return -EINVAL;
532	}
533}
534
535static int mtdchar_write_ioctl(struct mtd_info *mtd,
536		struct mtd_write_req __user *argp)
537{
538	struct mtd_write_req req;
539	struct mtd_oob_ops ops;
540	const void __user *usr_data, *usr_oob;
541	int ret;
542
543	if (copy_from_user(&req, argp, sizeof(req)))
544		return -EFAULT;
545
546	usr_data = (const void __user *)(uintptr_t)req.usr_data;
547	usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
548	if (!access_ok(VERIFY_READ, usr_data, req.len) ||
549	    !access_ok(VERIFY_READ, usr_oob, req.ooblen))
550		return -EFAULT;
551
552	if (!mtd->_write_oob)
553		return -EOPNOTSUPP;
554
555	ops.mode = req.mode;
556	ops.len = (size_t)req.len;
557	ops.ooblen = (size_t)req.ooblen;
558	ops.ooboffs = 0;
559
560	if (usr_data) {
561		ops.datbuf = memdup_user(usr_data, ops.len);
562		if (IS_ERR(ops.datbuf))
563			return PTR_ERR(ops.datbuf);
564	} else {
565		ops.datbuf = NULL;
566	}
567
568	if (usr_oob) {
569		ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
570		if (IS_ERR(ops.oobbuf)) {
571			kfree(ops.datbuf);
572			return PTR_ERR(ops.oobbuf);
573		}
574	} else {
575		ops.oobbuf = NULL;
576	}
577
578	ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
579
580	kfree(ops.datbuf);
581	kfree(ops.oobbuf);
582
583	return ret;
584}
585
586static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
587{
588	struct mtd_file_info *mfi = file->private_data;
589	struct mtd_info *mtd = mfi->mtd;
590	void __user *argp = (void __user *)arg;
591	int ret = 0;
592	u_long size;
593	struct mtd_info_user info;
594
595	pr_debug("MTD_ioctl\n");
596
597	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
598	if (cmd & IOC_IN) {
599		if (!access_ok(VERIFY_READ, argp, size))
600			return -EFAULT;
601	}
602	if (cmd & IOC_OUT) {
603		if (!access_ok(VERIFY_WRITE, argp, size))
604			return -EFAULT;
605	}
606
607	switch (cmd) {
608	case MEMGETREGIONCOUNT:
609		if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
610			return -EFAULT;
611		break;
612
613	case MEMGETREGIONINFO:
614	{
615		uint32_t ur_idx;
616		struct mtd_erase_region_info *kr;
617		struct region_info_user __user *ur = argp;
618
619		if (get_user(ur_idx, &(ur->regionindex)))
620			return -EFAULT;
621
622		if (ur_idx >= mtd->numeraseregions)
623			return -EINVAL;
624
625		kr = &(mtd->eraseregions[ur_idx]);
626
627		if (put_user(kr->offset, &(ur->offset))
628		    || put_user(kr->erasesize, &(ur->erasesize))
629		    || put_user(kr->numblocks, &(ur->numblocks)))
630			return -EFAULT;
631
632		break;
633	}
634
635	case MEMGETINFO:
636		memset(&info, 0, sizeof(info));
637		info.type	= mtd->type;
638		info.flags	= mtd->flags;
639		info.size	= mtd->size;
640		info.erasesize	= mtd->erasesize;
641		info.writesize	= mtd->writesize;
642		info.oobsize	= mtd->oobsize;
643		/* The below field is obsolete */
644		info.padding	= 0;
645		if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
646			return -EFAULT;
647		break;
648
649	case MEMERASE:
650	case MEMERASE64:
651	{
652		struct erase_info *erase;
653
654		if(!(file->f_mode & FMODE_WRITE))
655			return -EPERM;
656
657		erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
658		if (!erase)
659			ret = -ENOMEM;
660		else {
661			wait_queue_head_t waitq;
662			DECLARE_WAITQUEUE(wait, current);
663
664			init_waitqueue_head(&waitq);
665
666			if (cmd == MEMERASE64) {
667				struct erase_info_user64 einfo64;
668
669				if (copy_from_user(&einfo64, argp,
670					    sizeof(struct erase_info_user64))) {
671					kfree(erase);
672					return -EFAULT;
673				}
674				erase->addr = einfo64.start;
675				erase->len = einfo64.length;
676			} else {
677				struct erase_info_user einfo32;
678
679				if (copy_from_user(&einfo32, argp,
680					    sizeof(struct erase_info_user))) {
681					kfree(erase);
682					return -EFAULT;
683				}
684				erase->addr = einfo32.start;
685				erase->len = einfo32.length;
686			}
687			erase->mtd = mtd;
688			erase->callback = mtdchar_erase_callback;
689			erase->priv = (unsigned long)&waitq;
690
691			/*
692			  FIXME: Allow INTERRUPTIBLE. Which means
693			  not having the wait_queue head on the stack.
694
695			  If the wq_head is on the stack, and we
696			  leave because we got interrupted, then the
697			  wq_head is no longer there when the
698			  callback routine tries to wake us up.
699			*/
700			ret = mtd_erase(mtd, erase);
701			if (!ret) {
702				set_current_state(TASK_UNINTERRUPTIBLE);
703				add_wait_queue(&waitq, &wait);
704				if (erase->state != MTD_ERASE_DONE &&
705				    erase->state != MTD_ERASE_FAILED)
706					schedule();
707				remove_wait_queue(&waitq, &wait);
708				set_current_state(TASK_RUNNING);
709
710				ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
711			}
712			kfree(erase);
713		}
714		break;
715	}
716
717	case MEMWRITEOOB:
718	{
719		struct mtd_oob_buf buf;
720		struct mtd_oob_buf __user *buf_user = argp;
721
722		/* NOTE: writes return length to buf_user->length */
723		if (copy_from_user(&buf, argp, sizeof(buf)))
724			ret = -EFAULT;
725		else
726			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
727				buf.ptr, &buf_user->length);
728		break;
729	}
730
731	case MEMREADOOB:
732	{
733		struct mtd_oob_buf buf;
734		struct mtd_oob_buf __user *buf_user = argp;
735
736		/* NOTE: writes return length to buf_user->start */
737		if (copy_from_user(&buf, argp, sizeof(buf)))
738			ret = -EFAULT;
739		else
740			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
741				buf.ptr, &buf_user->start);
742		break;
743	}
744
745	case MEMWRITEOOB64:
746	{
747		struct mtd_oob_buf64 buf;
748		struct mtd_oob_buf64 __user *buf_user = argp;
749
750		if (copy_from_user(&buf, argp, sizeof(buf)))
751			ret = -EFAULT;
752		else
753			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
754				(void __user *)(uintptr_t)buf.usr_ptr,
755				&buf_user->length);
756		break;
757	}
758
759	case MEMREADOOB64:
760	{
761		struct mtd_oob_buf64 buf;
762		struct mtd_oob_buf64 __user *buf_user = argp;
763
764		if (copy_from_user(&buf, argp, sizeof(buf)))
765			ret = -EFAULT;
766		else
767			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
768				(void __user *)(uintptr_t)buf.usr_ptr,
769				&buf_user->length);
770		break;
771	}
772
773	case MEMWRITE:
774	{
775		ret = mtdchar_write_ioctl(mtd,
776		      (struct mtd_write_req __user *)arg);
777		break;
778	}
779
780	case MEMLOCK:
781	{
782		struct erase_info_user einfo;
783
784		if (copy_from_user(&einfo, argp, sizeof(einfo)))
785			return -EFAULT;
786
787		ret = mtd_lock(mtd, einfo.start, einfo.length);
788		break;
789	}
790
791	case MEMUNLOCK:
792	{
793		struct erase_info_user einfo;
794
795		if (copy_from_user(&einfo, argp, sizeof(einfo)))
796			return -EFAULT;
797
798		ret = mtd_unlock(mtd, einfo.start, einfo.length);
799		break;
800	}
801
802	case MEMISLOCKED:
803	{
804		struct erase_info_user einfo;
805
806		if (copy_from_user(&einfo, argp, sizeof(einfo)))
807			return -EFAULT;
808
809		ret = mtd_is_locked(mtd, einfo.start, einfo.length);
810		break;
811	}
812
813	/* Legacy interface */
814	case MEMGETOOBSEL:
815	{
816		struct nand_oobinfo oi;
817
818		if (!mtd->ecclayout)
819			return -EOPNOTSUPP;
820		if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
821			return -EINVAL;
822
823		oi.useecc = MTD_NANDECC_AUTOPLACE;
824		memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
825		memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
826		       sizeof(oi.oobfree));
827		oi.eccbytes = mtd->ecclayout->eccbytes;
828
829		if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
830			return -EFAULT;
831		break;
832	}
833
834	case MEMGETBADBLOCK:
835	{
836		loff_t offs;
837
838		if (copy_from_user(&offs, argp, sizeof(loff_t)))
839			return -EFAULT;
840		return mtd_block_isbad(mtd, offs);
841		break;
842	}
843
844	case MEMSETBADBLOCK:
845	{
846		loff_t offs;
847
848		if (copy_from_user(&offs, argp, sizeof(loff_t)))
849			return -EFAULT;
850		return mtd_block_markbad(mtd, offs);
851		break;
852	}
853
854	case OTPSELECT:
855	{
856		int mode;
857		if (copy_from_user(&mode, argp, sizeof(int)))
858			return -EFAULT;
859
860		mfi->mode = MTD_FILE_MODE_NORMAL;
861
862		ret = otp_select_filemode(mfi, mode);
863
864		file->f_pos = 0;
865		break;
866	}
867
868	case OTPGETREGIONCOUNT:
869	case OTPGETREGIONINFO:
870	{
871		struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
872		size_t retlen;
873		if (!buf)
874			return -ENOMEM;
875		switch (mfi->mode) {
876		case MTD_FILE_MODE_OTP_FACTORY:
877			ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
878			break;
879		case MTD_FILE_MODE_OTP_USER:
880			ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
881			break;
882		default:
883			ret = -EINVAL;
884			break;
885		}
886		if (!ret) {
887			if (cmd == OTPGETREGIONCOUNT) {
888				int nbr = retlen / sizeof(struct otp_info);
889				ret = copy_to_user(argp, &nbr, sizeof(int));
890			} else
891				ret = copy_to_user(argp, buf, retlen);
892			if (ret)
893				ret = -EFAULT;
894		}
895		kfree(buf);
896		break;
897	}
898
899	case OTPLOCK:
900	{
901		struct otp_info oinfo;
902
903		if (mfi->mode != MTD_FILE_MODE_OTP_USER)
904			return -EINVAL;
905		if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
906			return -EFAULT;
907		ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
908		break;
909	}
910
911	/* This ioctl is being deprecated - it truncates the ECC layout */
912	case ECCGETLAYOUT:
913	{
914		struct nand_ecclayout_user *usrlay;
915
916		if (!mtd->ecclayout)
917			return -EOPNOTSUPP;
918
919		usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
920		if (!usrlay)
921			return -ENOMEM;
922
923		shrink_ecclayout(mtd->ecclayout, usrlay);
924
925		if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
926			ret = -EFAULT;
927		kfree(usrlay);
928		break;
929	}
930
931	case ECCGETSTATS:
932	{
933		if (copy_to_user(argp, &mtd->ecc_stats,
934				 sizeof(struct mtd_ecc_stats)))
935			return -EFAULT;
936		break;
937	}
938
939	case MTDFILEMODE:
940	{
941		mfi->mode = 0;
942
943		switch(arg) {
944		case MTD_FILE_MODE_OTP_FACTORY:
945		case MTD_FILE_MODE_OTP_USER:
946			ret = otp_select_filemode(mfi, arg);
947			break;
948
949		case MTD_FILE_MODE_RAW:
950			if (!mtd_has_oob(mtd))
951				return -EOPNOTSUPP;
952			mfi->mode = arg;
953
954		case MTD_FILE_MODE_NORMAL:
955			break;
956		default:
957			ret = -EINVAL;
958		}
959		file->f_pos = 0;
960		break;
961	}
962
963	case BLKPG:
964	{
965		struct blkpg_ioctl_arg __user *blk_arg = argp;
966		struct blkpg_ioctl_arg a;
967
968		if (copy_from_user(&a, blk_arg, sizeof(a)))
969			ret = -EFAULT;
970		else
971			ret = mtdchar_blkpg_ioctl(mtd, &a);
972		break;
973	}
974
975	case BLKRRPART:
976	{
977		/* No reread partition feature. Just return ok */
978		ret = 0;
979		break;
980	}
981
982	default:
983		ret = -ENOTTY;
984	}
985
986	return ret;
987} /* memory_ioctl */
988
989static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
990{
991	int ret;
992
993	mutex_lock(&mtd_mutex);
994	ret = mtdchar_ioctl(file, cmd, arg);
995	mutex_unlock(&mtd_mutex);
996
997	return ret;
998}
999
1000#ifdef CONFIG_COMPAT
1001
1002struct mtd_oob_buf32 {
1003	u_int32_t start;
1004	u_int32_t length;
1005	compat_caddr_t ptr;	/* unsigned char* */
1006};
1007
1008#define MEMWRITEOOB32		_IOWR('M', 3, struct mtd_oob_buf32)
1009#define MEMREADOOB32		_IOWR('M', 4, struct mtd_oob_buf32)
1010
1011static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1012	unsigned long arg)
1013{
1014	struct mtd_file_info *mfi = file->private_data;
1015	struct mtd_info *mtd = mfi->mtd;
1016	void __user *argp = compat_ptr(arg);
1017	int ret = 0;
1018
1019	mutex_lock(&mtd_mutex);
1020
1021	switch (cmd) {
1022	case MEMWRITEOOB32:
1023	{
1024		struct mtd_oob_buf32 buf;
1025		struct mtd_oob_buf32 __user *buf_user = argp;
1026
1027		if (copy_from_user(&buf, argp, sizeof(buf)))
1028			ret = -EFAULT;
1029		else
1030			ret = mtdchar_writeoob(file, mtd, buf.start,
1031				buf.length, compat_ptr(buf.ptr),
1032				&buf_user->length);
1033		break;
1034	}
1035
1036	case MEMREADOOB32:
1037	{
1038		struct mtd_oob_buf32 buf;
1039		struct mtd_oob_buf32 __user *buf_user = argp;
1040
1041		/* NOTE: writes return length to buf->start */
1042		if (copy_from_user(&buf, argp, sizeof(buf)))
1043			ret = -EFAULT;
1044		else
1045			ret = mtdchar_readoob(file, mtd, buf.start,
1046				buf.length, compat_ptr(buf.ptr),
1047				&buf_user->start);
1048		break;
1049	}
1050
1051	case BLKPG:
1052	{
1053		/* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1054		struct blkpg_compat_ioctl_arg __user *uarg = argp;
1055		struct blkpg_compat_ioctl_arg compat_arg;
1056		struct blkpg_ioctl_arg a;
1057
1058		if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1059			ret = -EFAULT;
1060			break;
1061		}
1062
1063		memset(&a, 0, sizeof(a));
1064		a.op = compat_arg.op;
1065		a.flags = compat_arg.flags;
1066		a.datalen = compat_arg.datalen;
1067		a.data = compat_ptr(compat_arg.data);
1068
1069		ret = mtdchar_blkpg_ioctl(mtd, &a);
1070		break;
1071	}
1072
1073	default:
1074		ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1075	}
1076
1077	mutex_unlock(&mtd_mutex);
1078
1079	return ret;
1080}
1081
1082#endif /* CONFIG_COMPAT */
1083
1084/*
1085 * try to determine where a shared mapping can be made
1086 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1087 *   mappings)
1088 */
1089#ifndef CONFIG_MMU
1090static unsigned long mtdchar_get_unmapped_area(struct file *file,
1091					   unsigned long addr,
1092					   unsigned long len,
1093					   unsigned long pgoff,
1094					   unsigned long flags)
1095{
1096	struct mtd_file_info *mfi = file->private_data;
1097	struct mtd_info *mtd = mfi->mtd;
1098	unsigned long offset;
1099	int ret;
1100
1101	if (addr != 0)
1102		return (unsigned long) -EINVAL;
1103
1104	if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1105		return (unsigned long) -EINVAL;
1106
1107	offset = pgoff << PAGE_SHIFT;
1108	if (offset > mtd->size - len)
1109		return (unsigned long) -EINVAL;
1110
1111	ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1112	return ret == -EOPNOTSUPP ? -ENODEV : ret;
1113}
1114
1115static unsigned mtdchar_mmap_capabilities(struct file *file)
1116{
1117	struct mtd_file_info *mfi = file->private_data;
1118
1119	return mtd_mmap_capabilities(mfi->mtd);
1120}
1121#endif
1122
1123/*
1124 * set up a mapping for shared memory segments
1125 */
1126static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1127{
1128#ifdef CONFIG_MMU
1129	struct mtd_file_info *mfi = file->private_data;
1130	struct mtd_info *mtd = mfi->mtd;
1131	struct map_info *map = mtd->priv;
1132
1133        /* This is broken because it assumes the MTD device is map-based
1134	   and that mtd->priv is a valid struct map_info.  It should be
1135	   replaced with something that uses the mtd_get_unmapped_area()
1136	   operation properly. */
1137	if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1138#ifdef pgprot_noncached
1139		if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1140			vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1141#endif
1142		return vm_iomap_memory(vma, map->phys, map->size);
1143	}
1144	return -ENODEV;
1145#else
1146	return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1147#endif
1148}
1149
1150static const struct file_operations mtd_fops = {
1151	.owner		= THIS_MODULE,
1152	.llseek		= mtdchar_lseek,
1153	.read		= mtdchar_read,
1154	.write		= mtdchar_write,
1155	.unlocked_ioctl	= mtdchar_unlocked_ioctl,
1156#ifdef CONFIG_COMPAT
1157	.compat_ioctl	= mtdchar_compat_ioctl,
1158#endif
1159	.open		= mtdchar_open,
1160	.release	= mtdchar_close,
1161	.mmap		= mtdchar_mmap,
1162#ifndef CONFIG_MMU
1163	.get_unmapped_area = mtdchar_get_unmapped_area,
1164	.mmap_capabilities = mtdchar_mmap_capabilities,
1165#endif
1166};
1167
1168int __init init_mtdchar(void)
1169{
1170	int ret;
1171
1172	ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1173				   "mtd", &mtd_fops);
1174	if (ret < 0) {
1175		pr_err("Can't allocate major number %d for MTD\n",
1176		       MTD_CHAR_MAJOR);
1177		return ret;
1178	}
1179
1180	return ret;
1181}
1182
1183void __exit cleanup_mtdchar(void)
1184{
1185	__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1186}
1187
1188MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
1189