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v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4 */
   5
   6#include <linux/device.h>
   7#include <linux/fs.h>
   8#include <linux/mm.h>
   9#include <linux/err.h>
  10#include <linux/init.h>
  11#include <linux/kernel.h>
  12#include <linux/module.h>
  13#include <linux/slab.h>
  14#include <linux/sched.h>
  15#include <linux/mutex.h>
  16#include <linux/backing-dev.h>
  17#include <linux/compat.h>
  18#include <linux/mount.h>
  19#include <linux/blkpg.h>
  20#include <linux/magic.h>
  21#include <linux/major.h>
  22#include <linux/mtd/mtd.h>
  23#include <linux/mtd/partitions.h>
  24#include <linux/mtd/map.h>
  25
  26#include <linux/uaccess.h>
  27
  28#include "mtdcore.h"
  29
  30static DEFINE_MUTEX(mtd_mutex);
  31
  32/*
  33 * Data structure to hold the pointer to the mtd device as well
  34 * as mode information of various use cases.
  35 */
  36struct mtd_file_info {
  37	struct mtd_info *mtd;
  38	enum mtd_file_modes mode;
  39};
  40
  41static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
  42{
  43	struct mtd_file_info *mfi = file->private_data;
  44	return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
  45}
  46
  47static int mtdchar_open(struct inode *inode, struct file *file)
  48{
  49	int minor = iminor(inode);
  50	int devnum = minor >> 1;
  51	int ret = 0;
  52	struct mtd_info *mtd;
  53	struct mtd_file_info *mfi;
  54
  55	pr_debug("MTD_open\n");
  56
  57	/* You can't open the RO devices RW */
  58	if ((file->f_mode & FMODE_WRITE) && (minor & 1))
  59		return -EACCES;
  60
  61	mutex_lock(&mtd_mutex);
  62	mtd = get_mtd_device(NULL, devnum);
  63
  64	if (IS_ERR(mtd)) {
  65		ret = PTR_ERR(mtd);
  66		goto out;
  67	}
  68
  69	if (mtd->type == MTD_ABSENT) {
  70		ret = -ENODEV;
  71		goto out1;
  72	}
  73
  74	/* You can't open it RW if it's not a writeable device */
  75	if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
  76		ret = -EACCES;
  77		goto out1;
  78	}
  79
  80	mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
  81	if (!mfi) {
  82		ret = -ENOMEM;
  83		goto out1;
  84	}
  85	mfi->mtd = mtd;
  86	file->private_data = mfi;
  87	mutex_unlock(&mtd_mutex);
  88	return 0;
  89
  90out1:
  91	put_mtd_device(mtd);
  92out:
  93	mutex_unlock(&mtd_mutex);
  94	return ret;
  95} /* mtdchar_open */
  96
  97/*====================================================================*/
  98
  99static int mtdchar_close(struct inode *inode, struct file *file)
 100{
 101	struct mtd_file_info *mfi = file->private_data;
 102	struct mtd_info *mtd = mfi->mtd;
 103
 104	pr_debug("MTD_close\n");
 105
 106	/* Only sync if opened RW */
 107	if ((file->f_mode & FMODE_WRITE))
 108		mtd_sync(mtd);
 109
 110	put_mtd_device(mtd);
 111	file->private_data = NULL;
 112	kfree(mfi);
 113
 114	return 0;
 115} /* mtdchar_close */
 116
 117/* Back in June 2001, dwmw2 wrote:
 118 *
 119 *   FIXME: This _really_ needs to die. In 2.5, we should lock the
 120 *   userspace buffer down and use it directly with readv/writev.
 121 *
 122 * The implementation below, using mtd_kmalloc_up_to, mitigates
 123 * allocation failures when the system is under low-memory situations
 124 * or if memory is highly fragmented at the cost of reducing the
 125 * performance of the requested transfer due to a smaller buffer size.
 126 *
 127 * A more complex but more memory-efficient implementation based on
 128 * get_user_pages and iovecs to cover extents of those pages is a
 129 * longer-term goal, as intimated by dwmw2 above. However, for the
 130 * write case, this requires yet more complex head and tail transfer
 131 * handling when those head and tail offsets and sizes are such that
 132 * alignment requirements are not met in the NAND subdriver.
 133 */
 134
 135static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
 136			loff_t *ppos)
 137{
 138	struct mtd_file_info *mfi = file->private_data;
 139	struct mtd_info *mtd = mfi->mtd;
 140	size_t retlen;
 141	size_t total_retlen=0;
 142	int ret=0;
 143	int len;
 144	size_t size = count;
 145	char *kbuf;
 146
 147	pr_debug("MTD_read\n");
 148
 149	if (*ppos + count > mtd->size) {
 150		if (*ppos < mtd->size)
 151			count = mtd->size - *ppos;
 152		else
 153			count = 0;
 154	}
 155
 156	if (!count)
 157		return 0;
 158
 159	kbuf = mtd_kmalloc_up_to(mtd, &size);
 160	if (!kbuf)
 161		return -ENOMEM;
 162
 163	while (count) {
 164		len = min_t(size_t, count, size);
 165
 166		switch (mfi->mode) {
 167		case MTD_FILE_MODE_OTP_FACTORY:
 168			ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
 169						     &retlen, kbuf);
 170			break;
 171		case MTD_FILE_MODE_OTP_USER:
 172			ret = mtd_read_user_prot_reg(mtd, *ppos, len,
 173						     &retlen, kbuf);
 174			break;
 175		case MTD_FILE_MODE_RAW:
 176		{
 177			struct mtd_oob_ops ops;
 178
 179			ops.mode = MTD_OPS_RAW;
 180			ops.datbuf = kbuf;
 181			ops.oobbuf = NULL;
 182			ops.len = len;
 183
 184			ret = mtd_read_oob(mtd, *ppos, &ops);
 185			retlen = ops.retlen;
 186			break;
 187		}
 188		default:
 189			ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
 190		}
 191		/* Nand returns -EBADMSG on ECC errors, but it returns
 192		 * the data. For our userspace tools it is important
 193		 * to dump areas with ECC errors!
 194		 * For kernel internal usage it also might return -EUCLEAN
 195		 * to signal the caller that a bitflip has occurred and has
 196		 * been corrected by the ECC algorithm.
 197		 * Userspace software which accesses NAND this way
 198		 * must be aware of the fact that it deals with NAND
 199		 */
 200		if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
 201			*ppos += retlen;
 202			if (copy_to_user(buf, kbuf, retlen)) {
 203				kfree(kbuf);
 204				return -EFAULT;
 205			}
 206			else
 207				total_retlen += retlen;
 208
 209			count -= retlen;
 210			buf += retlen;
 211			if (retlen == 0)
 212				count = 0;
 213		}
 214		else {
 215			kfree(kbuf);
 216			return ret;
 217		}
 218
 219	}
 220
 221	kfree(kbuf);
 222	return total_retlen;
 223} /* mtdchar_read */
 224
 225static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
 226			loff_t *ppos)
 227{
 228	struct mtd_file_info *mfi = file->private_data;
 229	struct mtd_info *mtd = mfi->mtd;
 230	size_t size = count;
 231	char *kbuf;
 232	size_t retlen;
 233	size_t total_retlen=0;
 234	int ret=0;
 235	int len;
 236
 237	pr_debug("MTD_write\n");
 238
 239	if (*ppos >= mtd->size)
 240		return -ENOSPC;
 241
 242	if (*ppos + count > mtd->size)
 243		count = mtd->size - *ppos;
 244
 245	if (!count)
 246		return 0;
 247
 248	kbuf = mtd_kmalloc_up_to(mtd, &size);
 249	if (!kbuf)
 250		return -ENOMEM;
 251
 252	while (count) {
 253		len = min_t(size_t, count, size);
 254
 255		if (copy_from_user(kbuf, buf, len)) {
 256			kfree(kbuf);
 257			return -EFAULT;
 258		}
 259
 260		switch (mfi->mode) {
 261		case MTD_FILE_MODE_OTP_FACTORY:
 262			ret = -EROFS;
 263			break;
 264		case MTD_FILE_MODE_OTP_USER:
 265			ret = mtd_write_user_prot_reg(mtd, *ppos, len,
 266						      &retlen, kbuf);
 267			break;
 268
 269		case MTD_FILE_MODE_RAW:
 270		{
 271			struct mtd_oob_ops ops;
 272
 273			ops.mode = MTD_OPS_RAW;
 274			ops.datbuf = kbuf;
 275			ops.oobbuf = NULL;
 276			ops.ooboffs = 0;
 277			ops.len = len;
 278
 279			ret = mtd_write_oob(mtd, *ppos, &ops);
 280			retlen = ops.retlen;
 281			break;
 282		}
 283
 284		default:
 285			ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
 286		}
 287
 288		/*
 289		 * Return -ENOSPC only if no data could be written at all.
 290		 * Otherwise just return the number of bytes that actually
 291		 * have been written.
 292		 */
 293		if ((ret == -ENOSPC) && (total_retlen))
 294			break;
 295
 296		if (!ret) {
 297			*ppos += retlen;
 298			total_retlen += retlen;
 299			count -= retlen;
 300			buf += retlen;
 301		}
 302		else {
 303			kfree(kbuf);
 304			return ret;
 305		}
 306	}
 307
 308	kfree(kbuf);
 309	return total_retlen;
 310} /* mtdchar_write */
 311
 312/*======================================================================
 313
 314    IOCTL calls for getting device parameters.
 315
 316======================================================================*/
 
 
 
 
 317
 318static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 319{
 320	struct mtd_info *mtd = mfi->mtd;
 321	size_t retlen;
 322
 323	switch (mode) {
 324	case MTD_OTP_FACTORY:
 325		if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
 326				-EOPNOTSUPP)
 327			return -EOPNOTSUPP;
 328
 329		mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
 330		break;
 331	case MTD_OTP_USER:
 332		if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
 333				-EOPNOTSUPP)
 334			return -EOPNOTSUPP;
 335
 336		mfi->mode = MTD_FILE_MODE_OTP_USER;
 337		break;
 338	case MTD_OTP_OFF:
 339		mfi->mode = MTD_FILE_MODE_NORMAL;
 340		break;
 341	default:
 342		return -EINVAL;
 343	}
 344
 345	return 0;
 346}
 347
 348static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
 349	uint64_t start, uint32_t length, void __user *ptr,
 350	uint32_t __user *retp)
 351{
 352	struct mtd_file_info *mfi = file->private_data;
 353	struct mtd_oob_ops ops;
 354	uint32_t retlen;
 355	int ret = 0;
 356
 357	if (!(file->f_mode & FMODE_WRITE))
 358		return -EPERM;
 359
 360	if (length > 4096)
 361		return -EINVAL;
 362
 363	if (!mtd->_write_oob)
 364		return -EOPNOTSUPP;
 
 
 
 
 
 365
 366	ops.ooblen = length;
 367	ops.ooboffs = start & (mtd->writesize - 1);
 368	ops.datbuf = NULL;
 369	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
 370		MTD_OPS_PLACE_OOB;
 371
 372	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 373		return -EINVAL;
 374
 375	ops.oobbuf = memdup_user(ptr, length);
 376	if (IS_ERR(ops.oobbuf))
 377		return PTR_ERR(ops.oobbuf);
 378
 379	start &= ~((uint64_t)mtd->writesize - 1);
 380	ret = mtd_write_oob(mtd, start, &ops);
 381
 382	if (ops.oobretlen > 0xFFFFFFFFU)
 383		ret = -EOVERFLOW;
 384	retlen = ops.oobretlen;
 385	if (copy_to_user(retp, &retlen, sizeof(length)))
 386		ret = -EFAULT;
 387
 388	kfree(ops.oobbuf);
 389	return ret;
 390}
 391
 392static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
 393	uint64_t start, uint32_t length, void __user *ptr,
 394	uint32_t __user *retp)
 395{
 396	struct mtd_file_info *mfi = file->private_data;
 397	struct mtd_oob_ops ops;
 398	int ret = 0;
 399
 400	if (length > 4096)
 401		return -EINVAL;
 402
 
 
 
 403	ops.ooblen = length;
 404	ops.ooboffs = start & (mtd->writesize - 1);
 405	ops.datbuf = NULL;
 406	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
 407		MTD_OPS_PLACE_OOB;
 408
 409	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 410		return -EINVAL;
 411
 412	ops.oobbuf = kmalloc(length, GFP_KERNEL);
 413	if (!ops.oobbuf)
 414		return -ENOMEM;
 415
 416	start &= ~((uint64_t)mtd->writesize - 1);
 417	ret = mtd_read_oob(mtd, start, &ops);
 418
 419	if (put_user(ops.oobretlen, retp))
 420		ret = -EFAULT;
 421	else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
 422					    ops.oobretlen))
 423		ret = -EFAULT;
 424
 425	kfree(ops.oobbuf);
 426
 427	/*
 428	 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
 429	 * data. For our userspace tools it is important to dump areas
 430	 * with ECC errors!
 431	 * For kernel internal usage it also might return -EUCLEAN
 432	 * to signal the caller that a bitflip has occurred and has
 433	 * been corrected by the ECC algorithm.
 434	 *
 435	 * Note: currently the standard NAND function, nand_read_oob_std,
 436	 * does not calculate ECC for the OOB area, so do not rely on
 437	 * this behavior unless you have replaced it with your own.
 438	 */
 439	if (mtd_is_bitflip_or_eccerr(ret))
 440		return 0;
 441
 442	return ret;
 443}
 444
 445/*
 446 * Copies (and truncates, if necessary) OOB layout information to the
 447 * deprecated layout struct, nand_ecclayout_user. This is necessary only to
 448 * support the deprecated API ioctl ECCGETLAYOUT while allowing all new
 449 * functionality to use mtd_ooblayout_ops flexibly (i.e. mtd_ooblayout_ops
 450 * can describe any kind of OOB layout with almost zero overhead from a
 451 * memory usage point of view).
 452 */
 453static int shrink_ecclayout(struct mtd_info *mtd,
 454			    struct nand_ecclayout_user *to)
 455{
 456	struct mtd_oob_region oobregion;
 457	int i, section = 0, ret;
 458
 459	if (!mtd || !to)
 460		return -EINVAL;
 461
 462	memset(to, 0, sizeof(*to));
 463
 464	to->eccbytes = 0;
 465	for (i = 0; i < MTD_MAX_ECCPOS_ENTRIES;) {
 466		u32 eccpos;
 467
 468		ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
 469		if (ret < 0) {
 470			if (ret != -ERANGE)
 471				return ret;
 472
 473			break;
 474		}
 475
 476		eccpos = oobregion.offset;
 477		for (; i < MTD_MAX_ECCPOS_ENTRIES &&
 478		       eccpos < oobregion.offset + oobregion.length; i++) {
 479			to->eccpos[i] = eccpos++;
 480			to->eccbytes++;
 481		}
 482	}
 483
 484	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
 485		ret = mtd_ooblayout_free(mtd, i, &oobregion);
 486		if (ret < 0) {
 487			if (ret != -ERANGE)
 488				return ret;
 489
 490			break;
 491		}
 492
 493		to->oobfree[i].offset = oobregion.offset;
 494		to->oobfree[i].length = oobregion.length;
 495		to->oobavail += to->oobfree[i].length;
 496	}
 497
 498	return 0;
 499}
 500
 501static int get_oobinfo(struct mtd_info *mtd, struct nand_oobinfo *to)
 502{
 503	struct mtd_oob_region oobregion;
 504	int i, section = 0, ret;
 505
 506	if (!mtd || !to)
 507		return -EINVAL;
 508
 509	memset(to, 0, sizeof(*to));
 510
 511	to->eccbytes = 0;
 512	for (i = 0; i < ARRAY_SIZE(to->eccpos);) {
 513		u32 eccpos;
 514
 515		ret = mtd_ooblayout_ecc(mtd, section++, &oobregion);
 516		if (ret < 0) {
 517			if (ret != -ERANGE)
 518				return ret;
 519
 520			break;
 521		}
 522
 523		if (oobregion.length + i > ARRAY_SIZE(to->eccpos))
 524			return -EINVAL;
 525
 526		eccpos = oobregion.offset;
 527		for (; eccpos < oobregion.offset + oobregion.length; i++) {
 528			to->eccpos[i] = eccpos++;
 529			to->eccbytes++;
 530		}
 531	}
 532
 533	for (i = 0; i < 8; i++) {
 534		ret = mtd_ooblayout_free(mtd, i, &oobregion);
 535		if (ret < 0) {
 536			if (ret != -ERANGE)
 537				return ret;
 538
 539			break;
 540		}
 541
 542		to->oobfree[i][0] = oobregion.offset;
 543		to->oobfree[i][1] = oobregion.length;
 544	}
 545
 546	to->useecc = MTD_NANDECC_AUTOPLACE;
 547
 548	return 0;
 549}
 550
 551static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
 552			       struct blkpg_ioctl_arg *arg)
 553{
 554	struct blkpg_partition p;
 555
 556	if (!capable(CAP_SYS_ADMIN))
 557		return -EPERM;
 558
 559	if (copy_from_user(&p, arg->data, sizeof(p)))
 560		return -EFAULT;
 561
 562	switch (arg->op) {
 563	case BLKPG_ADD_PARTITION:
 564
 565		/* Only master mtd device must be used to add partitions */
 566		if (mtd_is_partition(mtd))
 567			return -EINVAL;
 568
 569		/* Sanitize user input */
 570		p.devname[BLKPG_DEVNAMELTH - 1] = '\0';
 571
 572		return mtd_add_partition(mtd, p.devname, p.start, p.length);
 573
 574	case BLKPG_DEL_PARTITION:
 575
 576		if (p.pno < 0)
 577			return -EINVAL;
 578
 579		return mtd_del_partition(mtd, p.pno);
 580
 581	default:
 582		return -EINVAL;
 583	}
 584}
 585
 586static int mtdchar_write_ioctl(struct mtd_info *mtd,
 587		struct mtd_write_req __user *argp)
 588{
 589	struct mtd_write_req req;
 590	struct mtd_oob_ops ops;
 591	const void __user *usr_data, *usr_oob;
 592	int ret;
 593
 594	if (copy_from_user(&req, argp, sizeof(req)))
 595		return -EFAULT;
 596
 597	usr_data = (const void __user *)(uintptr_t)req.usr_data;
 598	usr_oob = (const void __user *)(uintptr_t)req.usr_oob;
 
 
 
 599
 600	if (!mtd->_write_oob)
 601		return -EOPNOTSUPP;
 602
 603	ops.mode = req.mode;
 604	ops.len = (size_t)req.len;
 605	ops.ooblen = (size_t)req.ooblen;
 606	ops.ooboffs = 0;
 607
 608	if (usr_data) {
 609		ops.datbuf = memdup_user(usr_data, ops.len);
 610		if (IS_ERR(ops.datbuf))
 611			return PTR_ERR(ops.datbuf);
 612	} else {
 613		ops.datbuf = NULL;
 614	}
 615
 616	if (usr_oob) {
 617		ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
 618		if (IS_ERR(ops.oobbuf)) {
 619			kfree(ops.datbuf);
 620			return PTR_ERR(ops.oobbuf);
 621		}
 622	} else {
 623		ops.oobbuf = NULL;
 624	}
 625
 626	ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
 627
 628	kfree(ops.datbuf);
 629	kfree(ops.oobbuf);
 630
 631	return ret;
 632}
 633
 634static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 635{
 636	struct mtd_file_info *mfi = file->private_data;
 637	struct mtd_info *mtd = mfi->mtd;
 638	void __user *argp = (void __user *)arg;
 639	int ret = 0;
 
 640	struct mtd_info_user info;
 641
 642	pr_debug("MTD_ioctl\n");
 643
 
 
 
 
 
 
 
 
 
 
 644	switch (cmd) {
 645	case MEMGETREGIONCOUNT:
 646		if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 647			return -EFAULT;
 648		break;
 649
 650	case MEMGETREGIONINFO:
 651	{
 652		uint32_t ur_idx;
 653		struct mtd_erase_region_info *kr;
 654		struct region_info_user __user *ur = argp;
 655
 656		if (get_user(ur_idx, &(ur->regionindex)))
 657			return -EFAULT;
 658
 659		if (ur_idx >= mtd->numeraseregions)
 660			return -EINVAL;
 661
 662		kr = &(mtd->eraseregions[ur_idx]);
 663
 664		if (put_user(kr->offset, &(ur->offset))
 665		    || put_user(kr->erasesize, &(ur->erasesize))
 666		    || put_user(kr->numblocks, &(ur->numblocks)))
 667			return -EFAULT;
 668
 669		break;
 670	}
 671
 672	case MEMGETINFO:
 673		memset(&info, 0, sizeof(info));
 674		info.type	= mtd->type;
 675		info.flags	= mtd->flags;
 676		info.size	= mtd->size;
 677		info.erasesize	= mtd->erasesize;
 678		info.writesize	= mtd->writesize;
 679		info.oobsize	= mtd->oobsize;
 680		/* The below field is obsolete */
 681		info.padding	= 0;
 682		if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 683			return -EFAULT;
 684		break;
 685
 686	case MEMERASE:
 687	case MEMERASE64:
 688	{
 689		struct erase_info *erase;
 690
 691		if(!(file->f_mode & FMODE_WRITE))
 692			return -EPERM;
 693
 694		erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 695		if (!erase)
 696			ret = -ENOMEM;
 697		else {
 
 
 
 
 
 698			if (cmd == MEMERASE64) {
 699				struct erase_info_user64 einfo64;
 700
 701				if (copy_from_user(&einfo64, argp,
 702					    sizeof(struct erase_info_user64))) {
 703					kfree(erase);
 704					return -EFAULT;
 705				}
 706				erase->addr = einfo64.start;
 707				erase->len = einfo64.length;
 708			} else {
 709				struct erase_info_user einfo32;
 710
 711				if (copy_from_user(&einfo32, argp,
 712					    sizeof(struct erase_info_user))) {
 713					kfree(erase);
 714					return -EFAULT;
 715				}
 716				erase->addr = einfo32.start;
 717				erase->len = einfo32.length;
 718			}
 719
 
 
 
 
 
 
 
 
 
 
 
 
 720			ret = mtd_erase(mtd, erase);
 
 
 
 
 
 
 
 
 
 
 
 721			kfree(erase);
 722		}
 723		break;
 724	}
 725
 726	case MEMWRITEOOB:
 727	{
 728		struct mtd_oob_buf buf;
 729		struct mtd_oob_buf __user *buf_user = argp;
 730
 731		/* NOTE: writes return length to buf_user->length */
 732		if (copy_from_user(&buf, argp, sizeof(buf)))
 733			ret = -EFAULT;
 734		else
 735			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
 736				buf.ptr, &buf_user->length);
 737		break;
 738	}
 739
 740	case MEMREADOOB:
 741	{
 742		struct mtd_oob_buf buf;
 743		struct mtd_oob_buf __user *buf_user = argp;
 744
 745		/* NOTE: writes return length to buf_user->start */
 746		if (copy_from_user(&buf, argp, sizeof(buf)))
 747			ret = -EFAULT;
 748		else
 749			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
 750				buf.ptr, &buf_user->start);
 751		break;
 752	}
 753
 754	case MEMWRITEOOB64:
 755	{
 756		struct mtd_oob_buf64 buf;
 757		struct mtd_oob_buf64 __user *buf_user = argp;
 758
 759		if (copy_from_user(&buf, argp, sizeof(buf)))
 760			ret = -EFAULT;
 761		else
 762			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
 763				(void __user *)(uintptr_t)buf.usr_ptr,
 764				&buf_user->length);
 765		break;
 766	}
 767
 768	case MEMREADOOB64:
 769	{
 770		struct mtd_oob_buf64 buf;
 771		struct mtd_oob_buf64 __user *buf_user = argp;
 772
 773		if (copy_from_user(&buf, argp, sizeof(buf)))
 774			ret = -EFAULT;
 775		else
 776			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
 777				(void __user *)(uintptr_t)buf.usr_ptr,
 778				&buf_user->length);
 779		break;
 780	}
 781
 782	case MEMWRITE:
 783	{
 784		ret = mtdchar_write_ioctl(mtd,
 785		      (struct mtd_write_req __user *)arg);
 786		break;
 787	}
 788
 789	case MEMLOCK:
 790	{
 791		struct erase_info_user einfo;
 792
 793		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 794			return -EFAULT;
 795
 796		ret = mtd_lock(mtd, einfo.start, einfo.length);
 797		break;
 798	}
 799
 800	case MEMUNLOCK:
 801	{
 802		struct erase_info_user einfo;
 803
 804		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 805			return -EFAULT;
 806
 807		ret = mtd_unlock(mtd, einfo.start, einfo.length);
 808		break;
 809	}
 810
 811	case MEMISLOCKED:
 812	{
 813		struct erase_info_user einfo;
 814
 815		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 816			return -EFAULT;
 817
 818		ret = mtd_is_locked(mtd, einfo.start, einfo.length);
 819		break;
 820	}
 821
 822	/* Legacy interface */
 823	case MEMGETOOBSEL:
 824	{
 825		struct nand_oobinfo oi;
 826
 827		if (!mtd->ooblayout)
 828			return -EOPNOTSUPP;
 
 
 829
 830		ret = get_oobinfo(mtd, &oi);
 831		if (ret)
 832			return ret;
 
 
 833
 834		if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 835			return -EFAULT;
 836		break;
 837	}
 838
 839	case MEMGETBADBLOCK:
 840	{
 841		loff_t offs;
 842
 843		if (copy_from_user(&offs, argp, sizeof(loff_t)))
 844			return -EFAULT;
 845		return mtd_block_isbad(mtd, offs);
 846		break;
 847	}
 848
 849	case MEMSETBADBLOCK:
 850	{
 851		loff_t offs;
 852
 853		if (copy_from_user(&offs, argp, sizeof(loff_t)))
 854			return -EFAULT;
 855		return mtd_block_markbad(mtd, offs);
 856		break;
 857	}
 858
 859	case OTPSELECT:
 860	{
 861		int mode;
 862		if (copy_from_user(&mode, argp, sizeof(int)))
 863			return -EFAULT;
 864
 865		mfi->mode = MTD_FILE_MODE_NORMAL;
 866
 867		ret = otp_select_filemode(mfi, mode);
 868
 869		file->f_pos = 0;
 870		break;
 871	}
 872
 873	case OTPGETREGIONCOUNT:
 874	case OTPGETREGIONINFO:
 875	{
 876		struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 877		size_t retlen;
 878		if (!buf)
 879			return -ENOMEM;
 880		switch (mfi->mode) {
 881		case MTD_FILE_MODE_OTP_FACTORY:
 882			ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
 883			break;
 884		case MTD_FILE_MODE_OTP_USER:
 885			ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
 886			break;
 887		default:
 888			ret = -EINVAL;
 889			break;
 890		}
 891		if (!ret) {
 892			if (cmd == OTPGETREGIONCOUNT) {
 893				int nbr = retlen / sizeof(struct otp_info);
 894				ret = copy_to_user(argp, &nbr, sizeof(int));
 895			} else
 896				ret = copy_to_user(argp, buf, retlen);
 897			if (ret)
 898				ret = -EFAULT;
 899		}
 900		kfree(buf);
 901		break;
 902	}
 903
 904	case OTPLOCK:
 905	{
 906		struct otp_info oinfo;
 907
 908		if (mfi->mode != MTD_FILE_MODE_OTP_USER)
 909			return -EINVAL;
 910		if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 911			return -EFAULT;
 912		ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 913		break;
 914	}
 915
 916	/* This ioctl is being deprecated - it truncates the ECC layout */
 917	case ECCGETLAYOUT:
 918	{
 919		struct nand_ecclayout_user *usrlay;
 920
 921		if (!mtd->ooblayout)
 922			return -EOPNOTSUPP;
 923
 924		usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
 925		if (!usrlay)
 926			return -ENOMEM;
 927
 928		shrink_ecclayout(mtd, usrlay);
 929
 930		if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
 931			ret = -EFAULT;
 932		kfree(usrlay);
 933		break;
 934	}
 935
 936	case ECCGETSTATS:
 937	{
 938		if (copy_to_user(argp, &mtd->ecc_stats,
 939				 sizeof(struct mtd_ecc_stats)))
 940			return -EFAULT;
 941		break;
 942	}
 943
 944	case MTDFILEMODE:
 945	{
 946		mfi->mode = 0;
 947
 948		switch(arg) {
 949		case MTD_FILE_MODE_OTP_FACTORY:
 950		case MTD_FILE_MODE_OTP_USER:
 951			ret = otp_select_filemode(mfi, arg);
 952			break;
 953
 954		case MTD_FILE_MODE_RAW:
 955			if (!mtd_has_oob(mtd))
 956				return -EOPNOTSUPP;
 957			mfi->mode = arg;
 958
 959		case MTD_FILE_MODE_NORMAL:
 960			break;
 961		default:
 962			ret = -EINVAL;
 963		}
 964		file->f_pos = 0;
 965		break;
 966	}
 967
 968	case BLKPG:
 969	{
 970		struct blkpg_ioctl_arg __user *blk_arg = argp;
 971		struct blkpg_ioctl_arg a;
 972
 973		if (copy_from_user(&a, blk_arg, sizeof(a)))
 974			ret = -EFAULT;
 975		else
 976			ret = mtdchar_blkpg_ioctl(mtd, &a);
 977		break;
 978	}
 979
 980	case BLKRRPART:
 981	{
 982		/* No reread partition feature. Just return ok */
 983		ret = 0;
 984		break;
 985	}
 986
 987	default:
 988		ret = -ENOTTY;
 989	}
 990
 991	return ret;
 992} /* memory_ioctl */
 993
 994static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
 995{
 996	int ret;
 997
 998	mutex_lock(&mtd_mutex);
 999	ret = mtdchar_ioctl(file, cmd, arg);
1000	mutex_unlock(&mtd_mutex);
1001
1002	return ret;
1003}
1004
1005#ifdef CONFIG_COMPAT
1006
1007struct mtd_oob_buf32 {
1008	u_int32_t start;
1009	u_int32_t length;
1010	compat_caddr_t ptr;	/* unsigned char* */
1011};
1012
1013#define MEMWRITEOOB32		_IOWR('M', 3, struct mtd_oob_buf32)
1014#define MEMREADOOB32		_IOWR('M', 4, struct mtd_oob_buf32)
1015
1016static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1017	unsigned long arg)
1018{
1019	struct mtd_file_info *mfi = file->private_data;
1020	struct mtd_info *mtd = mfi->mtd;
1021	void __user *argp = compat_ptr(arg);
1022	int ret = 0;
1023
1024	mutex_lock(&mtd_mutex);
1025
1026	switch (cmd) {
1027	case MEMWRITEOOB32:
1028	{
1029		struct mtd_oob_buf32 buf;
1030		struct mtd_oob_buf32 __user *buf_user = argp;
1031
1032		if (copy_from_user(&buf, argp, sizeof(buf)))
1033			ret = -EFAULT;
1034		else
1035			ret = mtdchar_writeoob(file, mtd, buf.start,
1036				buf.length, compat_ptr(buf.ptr),
1037				&buf_user->length);
1038		break;
1039	}
1040
1041	case MEMREADOOB32:
1042	{
1043		struct mtd_oob_buf32 buf;
1044		struct mtd_oob_buf32 __user *buf_user = argp;
1045
1046		/* NOTE: writes return length to buf->start */
1047		if (copy_from_user(&buf, argp, sizeof(buf)))
1048			ret = -EFAULT;
1049		else
1050			ret = mtdchar_readoob(file, mtd, buf.start,
1051				buf.length, compat_ptr(buf.ptr),
1052				&buf_user->start);
1053		break;
1054	}
1055
1056	case BLKPG:
1057	{
1058		/* Convert from blkpg_compat_ioctl_arg to blkpg_ioctl_arg */
1059		struct blkpg_compat_ioctl_arg __user *uarg = argp;
1060		struct blkpg_compat_ioctl_arg compat_arg;
1061		struct blkpg_ioctl_arg a;
1062
1063		if (copy_from_user(&compat_arg, uarg, sizeof(compat_arg))) {
1064			ret = -EFAULT;
1065			break;
1066		}
1067
1068		memset(&a, 0, sizeof(a));
1069		a.op = compat_arg.op;
1070		a.flags = compat_arg.flags;
1071		a.datalen = compat_arg.datalen;
1072		a.data = compat_ptr(compat_arg.data);
1073
1074		ret = mtdchar_blkpg_ioctl(mtd, &a);
1075		break;
1076	}
1077
1078	default:
1079		ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1080	}
1081
1082	mutex_unlock(&mtd_mutex);
1083
1084	return ret;
1085}
1086
1087#endif /* CONFIG_COMPAT */
1088
1089/*
1090 * try to determine where a shared mapping can be made
1091 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1092 *   mappings)
1093 */
1094#ifndef CONFIG_MMU
1095static unsigned long mtdchar_get_unmapped_area(struct file *file,
1096					   unsigned long addr,
1097					   unsigned long len,
1098					   unsigned long pgoff,
1099					   unsigned long flags)
1100{
1101	struct mtd_file_info *mfi = file->private_data;
1102	struct mtd_info *mtd = mfi->mtd;
1103	unsigned long offset;
1104	int ret;
1105
1106	if (addr != 0)
1107		return (unsigned long) -EINVAL;
1108
1109	if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1110		return (unsigned long) -EINVAL;
1111
1112	offset = pgoff << PAGE_SHIFT;
1113	if (offset > mtd->size - len)
1114		return (unsigned long) -EINVAL;
1115
1116	ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1117	return ret == -EOPNOTSUPP ? -ENODEV : ret;
1118}
1119
1120static unsigned mtdchar_mmap_capabilities(struct file *file)
1121{
1122	struct mtd_file_info *mfi = file->private_data;
1123
1124	return mtd_mmap_capabilities(mfi->mtd);
1125}
1126#endif
1127
1128/*
1129 * set up a mapping for shared memory segments
1130 */
1131static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1132{
1133#ifdef CONFIG_MMU
1134	struct mtd_file_info *mfi = file->private_data;
1135	struct mtd_info *mtd = mfi->mtd;
1136	struct map_info *map = mtd->priv;
1137
1138        /* This is broken because it assumes the MTD device is map-based
1139	   and that mtd->priv is a valid struct map_info.  It should be
1140	   replaced with something that uses the mtd_get_unmapped_area()
1141	   operation properly. */
1142	if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1143#ifdef pgprot_noncached
1144		if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1145			vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1146#endif
1147		return vm_iomap_memory(vma, map->phys, map->size);
1148	}
1149	return -ENODEV;
1150#else
1151	return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1152#endif
1153}
1154
1155static const struct file_operations mtd_fops = {
1156	.owner		= THIS_MODULE,
1157	.llseek		= mtdchar_lseek,
1158	.read		= mtdchar_read,
1159	.write		= mtdchar_write,
1160	.unlocked_ioctl	= mtdchar_unlocked_ioctl,
1161#ifdef CONFIG_COMPAT
1162	.compat_ioctl	= mtdchar_compat_ioctl,
1163#endif
1164	.open		= mtdchar_open,
1165	.release	= mtdchar_close,
1166	.mmap		= mtdchar_mmap,
1167#ifndef CONFIG_MMU
1168	.get_unmapped_area = mtdchar_get_unmapped_area,
1169	.mmap_capabilities = mtdchar_mmap_capabilities,
1170#endif
1171};
1172
1173int __init init_mtdchar(void)
1174{
1175	int ret;
1176
1177	ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1178				   "mtd", &mtd_fops);
1179	if (ret < 0) {
1180		pr_err("Can't allocate major number %d for MTD\n",
1181		       MTD_CHAR_MAJOR);
1182		return ret;
1183	}
1184
1185	return ret;
1186}
1187
1188void __exit cleanup_mtdchar(void)
1189{
1190	__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1191}
1192
1193MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
v4.6
 
   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);