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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);
v3.15
   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	struct inode *ino;
  53	enum mtd_file_modes mode;
  54};
  55
  56static loff_t mtdchar_lseek(struct file *file, loff_t offset, int orig)
  57{
  58	struct mtd_file_info *mfi = file->private_data;
  59	return fixed_size_llseek(file, offset, orig, mfi->mtd->size);
  60}
  61
  62static int count;
  63static struct vfsmount *mnt;
  64static struct file_system_type mtd_inodefs_type;
  65
  66static int mtdchar_open(struct inode *inode, struct file *file)
  67{
  68	int minor = iminor(inode);
  69	int devnum = minor >> 1;
  70	int ret = 0;
  71	struct mtd_info *mtd;
  72	struct mtd_file_info *mfi;
  73	struct inode *mtd_ino;
  74
  75	pr_debug("MTD_open\n");
  76
  77	/* You can't open the RO devices RW */
  78	if ((file->f_mode & FMODE_WRITE) && (minor & 1))
  79		return -EACCES;
  80
  81	ret = simple_pin_fs(&mtd_inodefs_type, &mnt, &count);
  82	if (ret)
  83		return ret;
  84
  85	mutex_lock(&mtd_mutex);
  86	mtd = get_mtd_device(NULL, devnum);
  87
  88	if (IS_ERR(mtd)) {
  89		ret = PTR_ERR(mtd);
  90		goto out;
  91	}
  92
  93	if (mtd->type == MTD_ABSENT) {
  94		ret = -ENODEV;
  95		goto out1;
  96	}
  97
  98	mtd_ino = iget_locked(mnt->mnt_sb, devnum);
  99	if (!mtd_ino) {
 100		ret = -ENOMEM;
 101		goto out1;
 102	}
 103	if (mtd_ino->i_state & I_NEW) {
 104		mtd_ino->i_private = mtd;
 105		mtd_ino->i_mode = S_IFCHR;
 106		mtd_ino->i_data.backing_dev_info = mtd->backing_dev_info;
 107		unlock_new_inode(mtd_ino);
 108	}
 109	file->f_mapping = mtd_ino->i_mapping;
 110
 111	/* You can't open it RW if it's not a writeable device */
 112	if ((file->f_mode & FMODE_WRITE) && !(mtd->flags & MTD_WRITEABLE)) {
 113		ret = -EACCES;
 114		goto out2;
 115	}
 116
 117	mfi = kzalloc(sizeof(*mfi), GFP_KERNEL);
 118	if (!mfi) {
 119		ret = -ENOMEM;
 120		goto out2;
 121	}
 122	mfi->ino = mtd_ino;
 123	mfi->mtd = mtd;
 124	file->private_data = mfi;
 125	mutex_unlock(&mtd_mutex);
 126	return 0;
 127
 128out2:
 129	iput(mtd_ino);
 130out1:
 131	put_mtd_device(mtd);
 132out:
 133	mutex_unlock(&mtd_mutex);
 134	simple_release_fs(&mnt, &count);
 135	return ret;
 136} /* mtdchar_open */
 137
 138/*====================================================================*/
 139
 140static int mtdchar_close(struct inode *inode, struct file *file)
 141{
 142	struct mtd_file_info *mfi = file->private_data;
 143	struct mtd_info *mtd = mfi->mtd;
 144
 145	pr_debug("MTD_close\n");
 146
 147	/* Only sync if opened RW */
 148	if ((file->f_mode & FMODE_WRITE))
 149		mtd_sync(mtd);
 150
 151	iput(mfi->ino);
 152
 153	put_mtd_device(mtd);
 154	file->private_data = NULL;
 155	kfree(mfi);
 156	simple_release_fs(&mnt, &count);
 157
 158	return 0;
 159} /* mtdchar_close */
 160
 161/* Back in June 2001, dwmw2 wrote:
 162 *
 163 *   FIXME: This _really_ needs to die. In 2.5, we should lock the
 164 *   userspace buffer down and use it directly with readv/writev.
 165 *
 166 * The implementation below, using mtd_kmalloc_up_to, mitigates
 167 * allocation failures when the system is under low-memory situations
 168 * or if memory is highly fragmented at the cost of reducing the
 169 * performance of the requested transfer due to a smaller buffer size.
 170 *
 171 * A more complex but more memory-efficient implementation based on
 172 * get_user_pages and iovecs to cover extents of those pages is a
 173 * longer-term goal, as intimated by dwmw2 above. However, for the
 174 * write case, this requires yet more complex head and tail transfer
 175 * handling when those head and tail offsets and sizes are such that
 176 * alignment requirements are not met in the NAND subdriver.
 177 */
 178
 179static ssize_t mtdchar_read(struct file *file, char __user *buf, size_t count,
 180			loff_t *ppos)
 181{
 182	struct mtd_file_info *mfi = file->private_data;
 183	struct mtd_info *mtd = mfi->mtd;
 184	size_t retlen;
 185	size_t total_retlen=0;
 186	int ret=0;
 187	int len;
 188	size_t size = count;
 189	char *kbuf;
 190
 191	pr_debug("MTD_read\n");
 192
 193	if (*ppos + count > mtd->size)
 194		count = mtd->size - *ppos;
 195
 196	if (!count)
 197		return 0;
 198
 199	kbuf = mtd_kmalloc_up_to(mtd, &size);
 200	if (!kbuf)
 201		return -ENOMEM;
 202
 203	while (count) {
 204		len = min_t(size_t, count, size);
 205
 206		switch (mfi->mode) {
 207		case MTD_FILE_MODE_OTP_FACTORY:
 208			ret = mtd_read_fact_prot_reg(mtd, *ppos, len,
 209						     &retlen, kbuf);
 210			break;
 211		case MTD_FILE_MODE_OTP_USER:
 212			ret = mtd_read_user_prot_reg(mtd, *ppos, len,
 213						     &retlen, kbuf);
 214			break;
 215		case MTD_FILE_MODE_RAW:
 216		{
 217			struct mtd_oob_ops ops;
 218
 219			ops.mode = MTD_OPS_RAW;
 220			ops.datbuf = kbuf;
 221			ops.oobbuf = NULL;
 222			ops.len = len;
 223
 224			ret = mtd_read_oob(mtd, *ppos, &ops);
 225			retlen = ops.retlen;
 226			break;
 227		}
 228		default:
 229			ret = mtd_read(mtd, *ppos, len, &retlen, kbuf);
 230		}
 231		/* Nand returns -EBADMSG on ECC errors, but it returns
 232		 * the data. For our userspace tools it is important
 233		 * to dump areas with ECC errors!
 234		 * For kernel internal usage it also might return -EUCLEAN
 235		 * to signal the caller that a bitflip has occurred and has
 236		 * been corrected by the ECC algorithm.
 237		 * Userspace software which accesses NAND this way
 238		 * must be aware of the fact that it deals with NAND
 239		 */
 240		if (!ret || mtd_is_bitflip_or_eccerr(ret)) {
 241			*ppos += retlen;
 242			if (copy_to_user(buf, kbuf, retlen)) {
 243				kfree(kbuf);
 244				return -EFAULT;
 245			}
 246			else
 247				total_retlen += retlen;
 248
 249			count -= retlen;
 250			buf += retlen;
 251			if (retlen == 0)
 252				count = 0;
 253		}
 254		else {
 255			kfree(kbuf);
 256			return ret;
 257		}
 258
 259	}
 260
 261	kfree(kbuf);
 262	return total_retlen;
 263} /* mtdchar_read */
 264
 265static ssize_t mtdchar_write(struct file *file, const char __user *buf, size_t count,
 266			loff_t *ppos)
 267{
 268	struct mtd_file_info *mfi = file->private_data;
 269	struct mtd_info *mtd = mfi->mtd;
 270	size_t size = count;
 271	char *kbuf;
 272	size_t retlen;
 273	size_t total_retlen=0;
 274	int ret=0;
 275	int len;
 276
 277	pr_debug("MTD_write\n");
 278
 279	if (*ppos == mtd->size)
 280		return -ENOSPC;
 281
 282	if (*ppos + count > mtd->size)
 283		count = mtd->size - *ppos;
 284
 285	if (!count)
 286		return 0;
 287
 288	kbuf = mtd_kmalloc_up_to(mtd, &size);
 289	if (!kbuf)
 290		return -ENOMEM;
 291
 292	while (count) {
 293		len = min_t(size_t, count, size);
 294
 295		if (copy_from_user(kbuf, buf, len)) {
 296			kfree(kbuf);
 297			return -EFAULT;
 298		}
 299
 300		switch (mfi->mode) {
 301		case MTD_FILE_MODE_OTP_FACTORY:
 302			ret = -EROFS;
 303			break;
 304		case MTD_FILE_MODE_OTP_USER:
 305			ret = mtd_write_user_prot_reg(mtd, *ppos, len,
 306						      &retlen, kbuf);
 307			break;
 308
 309		case MTD_FILE_MODE_RAW:
 310		{
 311			struct mtd_oob_ops ops;
 312
 313			ops.mode = MTD_OPS_RAW;
 314			ops.datbuf = kbuf;
 315			ops.oobbuf = NULL;
 316			ops.ooboffs = 0;
 317			ops.len = len;
 318
 319			ret = mtd_write_oob(mtd, *ppos, &ops);
 320			retlen = ops.retlen;
 321			break;
 322		}
 323
 324		default:
 325			ret = mtd_write(mtd, *ppos, len, &retlen, kbuf);
 326		}
 327
 328		/*
 329		 * Return -ENOSPC only if no data could be written at all.
 330		 * Otherwise just return the number of bytes that actually
 331		 * have been written.
 332		 */
 333		if ((ret == -ENOSPC) && (total_retlen))
 334			break;
 335
 336		if (!ret) {
 337			*ppos += retlen;
 338			total_retlen += retlen;
 339			count -= retlen;
 340			buf += retlen;
 341		}
 342		else {
 343			kfree(kbuf);
 344			return ret;
 345		}
 346	}
 347
 348	kfree(kbuf);
 349	return total_retlen;
 350} /* mtdchar_write */
 351
 352/*======================================================================
 353
 354    IOCTL calls for getting device parameters.
 355
 356======================================================================*/
 357static void mtdchar_erase_callback (struct erase_info *instr)
 358{
 359	wake_up((wait_queue_head_t *)instr->priv);
 360}
 361
 362static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 363{
 364	struct mtd_info *mtd = mfi->mtd;
 365	size_t retlen;
 366
 367	switch (mode) {
 368	case MTD_OTP_FACTORY:
 369		if (mtd_read_fact_prot_reg(mtd, -1, 0, &retlen, NULL) ==
 370				-EOPNOTSUPP)
 371			return -EOPNOTSUPP;
 372
 373		mfi->mode = MTD_FILE_MODE_OTP_FACTORY;
 374		break;
 375	case MTD_OTP_USER:
 376		if (mtd_read_user_prot_reg(mtd, -1, 0, &retlen, NULL) ==
 377				-EOPNOTSUPP)
 378			return -EOPNOTSUPP;
 379
 380		mfi->mode = MTD_FILE_MODE_OTP_USER;
 381		break;
 382	case MTD_OTP_OFF:
 383		mfi->mode = MTD_FILE_MODE_NORMAL;
 384		break;
 385	default:
 386		return -EINVAL;
 387	}
 388
 389	return 0;
 390}
 391
 392static int mtdchar_writeoob(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	uint32_t retlen;
 399	int ret = 0;
 400
 401	if (!(file->f_mode & FMODE_WRITE))
 402		return -EPERM;
 403
 404	if (length > 4096)
 405		return -EINVAL;
 406
 407	if (!mtd->_write_oob)
 408		ret = -EOPNOTSUPP;
 409	else
 410		ret = access_ok(VERIFY_READ, ptr, length) ? 0 : -EFAULT;
 411
 412	if (ret)
 413		return ret;
 414
 415	ops.ooblen = length;
 416	ops.ooboffs = start & (mtd->writesize - 1);
 417	ops.datbuf = NULL;
 418	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
 419		MTD_OPS_PLACE_OOB;
 420
 421	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 422		return -EINVAL;
 423
 424	ops.oobbuf = memdup_user(ptr, length);
 425	if (IS_ERR(ops.oobbuf))
 426		return PTR_ERR(ops.oobbuf);
 427
 428	start &= ~((uint64_t)mtd->writesize - 1);
 429	ret = mtd_write_oob(mtd, start, &ops);
 430
 431	if (ops.oobretlen > 0xFFFFFFFFU)
 432		ret = -EOVERFLOW;
 433	retlen = ops.oobretlen;
 434	if (copy_to_user(retp, &retlen, sizeof(length)))
 435		ret = -EFAULT;
 436
 437	kfree(ops.oobbuf);
 438	return ret;
 439}
 440
 441static int mtdchar_readoob(struct file *file, struct mtd_info *mtd,
 442	uint64_t start, uint32_t length, void __user *ptr,
 443	uint32_t __user *retp)
 444{
 445	struct mtd_file_info *mfi = file->private_data;
 446	struct mtd_oob_ops ops;
 447	int ret = 0;
 448
 449	if (length > 4096)
 450		return -EINVAL;
 451
 452	if (!access_ok(VERIFY_WRITE, ptr, length))
 453		return -EFAULT;
 454
 455	ops.ooblen = length;
 456	ops.ooboffs = start & (mtd->writesize - 1);
 457	ops.datbuf = NULL;
 458	ops.mode = (mfi->mode == MTD_FILE_MODE_RAW) ? MTD_OPS_RAW :
 459		MTD_OPS_PLACE_OOB;
 460
 461	if (ops.ooboffs && ops.ooblen > (mtd->oobsize - ops.ooboffs))
 462		return -EINVAL;
 463
 464	ops.oobbuf = kmalloc(length, GFP_KERNEL);
 465	if (!ops.oobbuf)
 466		return -ENOMEM;
 467
 468	start &= ~((uint64_t)mtd->writesize - 1);
 469	ret = mtd_read_oob(mtd, start, &ops);
 470
 471	if (put_user(ops.oobretlen, retp))
 472		ret = -EFAULT;
 473	else if (ops.oobretlen && copy_to_user(ptr, ops.oobbuf,
 474					    ops.oobretlen))
 475		ret = -EFAULT;
 476
 477	kfree(ops.oobbuf);
 478
 479	/*
 480	 * NAND returns -EBADMSG on ECC errors, but it returns the OOB
 481	 * data. For our userspace tools it is important to dump areas
 482	 * with ECC errors!
 483	 * For kernel internal usage it also might return -EUCLEAN
 484	 * to signal the caller that a bitflip has occured and has
 485	 * been corrected by the ECC algorithm.
 486	 *
 487	 * Note: currently the standard NAND function, nand_read_oob_std,
 488	 * does not calculate ECC for the OOB area, so do not rely on
 489	 * this behavior unless you have replaced it with your own.
 490	 */
 491	if (mtd_is_bitflip_or_eccerr(ret))
 492		return 0;
 493
 494	return ret;
 495}
 496
 497/*
 498 * Copies (and truncates, if necessary) data from the larger struct,
 499 * nand_ecclayout, to the smaller, deprecated layout struct,
 500 * nand_ecclayout_user. This is necessary only to support the deprecated
 501 * API ioctl ECCGETLAYOUT while allowing all new functionality to use
 502 * nand_ecclayout flexibly (i.e. the struct may change size in new
 503 * releases without requiring major rewrites).
 504 */
 505static int shrink_ecclayout(const struct nand_ecclayout *from,
 506		struct nand_ecclayout_user *to)
 507{
 508	int i;
 509
 510	if (!from || !to)
 511		return -EINVAL;
 512
 513	memset(to, 0, sizeof(*to));
 514
 515	to->eccbytes = min((int)from->eccbytes, MTD_MAX_ECCPOS_ENTRIES);
 516	for (i = 0; i < to->eccbytes; i++)
 517		to->eccpos[i] = from->eccpos[i];
 518
 519	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES; i++) {
 520		if (from->oobfree[i].length == 0 &&
 521				from->oobfree[i].offset == 0)
 522			break;
 523		to->oobavail += from->oobfree[i].length;
 524		to->oobfree[i] = from->oobfree[i];
 525	}
 526
 527	return 0;
 528}
 529
 530static int mtdchar_blkpg_ioctl(struct mtd_info *mtd,
 531			   struct blkpg_ioctl_arg __user *arg)
 532{
 533	struct blkpg_ioctl_arg a;
 534	struct blkpg_partition p;
 535
 536	if (!capable(CAP_SYS_ADMIN))
 537		return -EPERM;
 538
 539	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
 540		return -EFAULT;
 541
 542	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
 543		return -EFAULT;
 544
 545	switch (a.op) {
 546	case BLKPG_ADD_PARTITION:
 547
 548		/* Only master mtd device must be used to add partitions */
 549		if (mtd_is_partition(mtd))
 550			return -EINVAL;
 551
 
 
 
 552		return mtd_add_partition(mtd, p.devname, p.start, p.length);
 553
 554	case BLKPG_DEL_PARTITION:
 555
 556		if (p.pno < 0)
 557			return -EINVAL;
 558
 559		return mtd_del_partition(mtd, p.pno);
 560
 561	default:
 562		return -EINVAL;
 563	}
 564}
 565
 566static int mtdchar_write_ioctl(struct mtd_info *mtd,
 567		struct mtd_write_req __user *argp)
 568{
 569	struct mtd_write_req req;
 570	struct mtd_oob_ops ops;
 571	void __user *usr_data, *usr_oob;
 572	int ret;
 573
 574	if (copy_from_user(&req, argp, sizeof(req)) ||
 575			!access_ok(VERIFY_READ, req.usr_data, req.len) ||
 576			!access_ok(VERIFY_READ, req.usr_oob, req.ooblen))
 
 
 
 
 577		return -EFAULT;
 
 578	if (!mtd->_write_oob)
 579		return -EOPNOTSUPP;
 580
 581	ops.mode = req.mode;
 582	ops.len = (size_t)req.len;
 583	ops.ooblen = (size_t)req.ooblen;
 584	ops.ooboffs = 0;
 585
 586	usr_data = (void __user *)(uintptr_t)req.usr_data;
 587	usr_oob = (void __user *)(uintptr_t)req.usr_oob;
 588
 589	if (req.usr_data) {
 590		ops.datbuf = memdup_user(usr_data, ops.len);
 591		if (IS_ERR(ops.datbuf))
 592			return PTR_ERR(ops.datbuf);
 593	} else {
 594		ops.datbuf = NULL;
 595	}
 596
 597	if (req.usr_oob) {
 598		ops.oobbuf = memdup_user(usr_oob, ops.ooblen);
 599		if (IS_ERR(ops.oobbuf)) {
 600			kfree(ops.datbuf);
 601			return PTR_ERR(ops.oobbuf);
 602		}
 603	} else {
 604		ops.oobbuf = NULL;
 605	}
 606
 607	ret = mtd_write_oob(mtd, (loff_t)req.start, &ops);
 608
 609	kfree(ops.datbuf);
 610	kfree(ops.oobbuf);
 611
 612	return ret;
 613}
 614
 615static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 616{
 617	struct mtd_file_info *mfi = file->private_data;
 618	struct mtd_info *mtd = mfi->mtd;
 619	void __user *argp = (void __user *)arg;
 620	int ret = 0;
 621	u_long size;
 622	struct mtd_info_user info;
 623
 624	pr_debug("MTD_ioctl\n");
 625
 626	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
 627	if (cmd & IOC_IN) {
 628		if (!access_ok(VERIFY_READ, argp, size))
 629			return -EFAULT;
 630	}
 631	if (cmd & IOC_OUT) {
 632		if (!access_ok(VERIFY_WRITE, argp, size))
 633			return -EFAULT;
 634	}
 635
 636	switch (cmd) {
 637	case MEMGETREGIONCOUNT:
 638		if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
 639			return -EFAULT;
 640		break;
 641
 642	case MEMGETREGIONINFO:
 643	{
 644		uint32_t ur_idx;
 645		struct mtd_erase_region_info *kr;
 646		struct region_info_user __user *ur = argp;
 647
 648		if (get_user(ur_idx, &(ur->regionindex)))
 649			return -EFAULT;
 650
 651		if (ur_idx >= mtd->numeraseregions)
 652			return -EINVAL;
 653
 654		kr = &(mtd->eraseregions[ur_idx]);
 655
 656		if (put_user(kr->offset, &(ur->offset))
 657		    || put_user(kr->erasesize, &(ur->erasesize))
 658		    || put_user(kr->numblocks, &(ur->numblocks)))
 659			return -EFAULT;
 660
 661		break;
 662	}
 663
 664	case MEMGETINFO:
 665		memset(&info, 0, sizeof(info));
 666		info.type	= mtd->type;
 667		info.flags	= mtd->flags;
 668		info.size	= mtd->size;
 669		info.erasesize	= mtd->erasesize;
 670		info.writesize	= mtd->writesize;
 671		info.oobsize	= mtd->oobsize;
 672		/* The below field is obsolete */
 673		info.padding	= 0;
 674		if (copy_to_user(argp, &info, sizeof(struct mtd_info_user)))
 675			return -EFAULT;
 676		break;
 677
 678	case MEMERASE:
 679	case MEMERASE64:
 680	{
 681		struct erase_info *erase;
 682
 683		if(!(file->f_mode & FMODE_WRITE))
 684			return -EPERM;
 685
 686		erase=kzalloc(sizeof(struct erase_info),GFP_KERNEL);
 687		if (!erase)
 688			ret = -ENOMEM;
 689		else {
 690			wait_queue_head_t waitq;
 691			DECLARE_WAITQUEUE(wait, current);
 692
 693			init_waitqueue_head(&waitq);
 694
 695			if (cmd == MEMERASE64) {
 696				struct erase_info_user64 einfo64;
 697
 698				if (copy_from_user(&einfo64, argp,
 699					    sizeof(struct erase_info_user64))) {
 700					kfree(erase);
 701					return -EFAULT;
 702				}
 703				erase->addr = einfo64.start;
 704				erase->len = einfo64.length;
 705			} else {
 706				struct erase_info_user einfo32;
 707
 708				if (copy_from_user(&einfo32, argp,
 709					    sizeof(struct erase_info_user))) {
 710					kfree(erase);
 711					return -EFAULT;
 712				}
 713				erase->addr = einfo32.start;
 714				erase->len = einfo32.length;
 715			}
 716			erase->mtd = mtd;
 717			erase->callback = mtdchar_erase_callback;
 718			erase->priv = (unsigned long)&waitq;
 719
 720			/*
 721			  FIXME: Allow INTERRUPTIBLE. Which means
 722			  not having the wait_queue head on the stack.
 723
 724			  If the wq_head is on the stack, and we
 725			  leave because we got interrupted, then the
 726			  wq_head is no longer there when the
 727			  callback routine tries to wake us up.
 728			*/
 729			ret = mtd_erase(mtd, erase);
 730			if (!ret) {
 731				set_current_state(TASK_UNINTERRUPTIBLE);
 732				add_wait_queue(&waitq, &wait);
 733				if (erase->state != MTD_ERASE_DONE &&
 734				    erase->state != MTD_ERASE_FAILED)
 735					schedule();
 736				remove_wait_queue(&waitq, &wait);
 737				set_current_state(TASK_RUNNING);
 738
 739				ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
 740			}
 741			kfree(erase);
 742		}
 743		break;
 744	}
 745
 746	case MEMWRITEOOB:
 747	{
 748		struct mtd_oob_buf buf;
 749		struct mtd_oob_buf __user *buf_user = argp;
 750
 751		/* NOTE: writes return length to buf_user->length */
 752		if (copy_from_user(&buf, argp, sizeof(buf)))
 753			ret = -EFAULT;
 754		else
 755			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
 756				buf.ptr, &buf_user->length);
 757		break;
 758	}
 759
 760	case MEMREADOOB:
 761	{
 762		struct mtd_oob_buf buf;
 763		struct mtd_oob_buf __user *buf_user = argp;
 764
 765		/* NOTE: writes return length to buf_user->start */
 766		if (copy_from_user(&buf, argp, sizeof(buf)))
 767			ret = -EFAULT;
 768		else
 769			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
 770				buf.ptr, &buf_user->start);
 771		break;
 772	}
 773
 774	case MEMWRITEOOB64:
 775	{
 776		struct mtd_oob_buf64 buf;
 777		struct mtd_oob_buf64 __user *buf_user = argp;
 778
 779		if (copy_from_user(&buf, argp, sizeof(buf)))
 780			ret = -EFAULT;
 781		else
 782			ret = mtdchar_writeoob(file, mtd, buf.start, buf.length,
 783				(void __user *)(uintptr_t)buf.usr_ptr,
 784				&buf_user->length);
 785		break;
 786	}
 787
 788	case MEMREADOOB64:
 789	{
 790		struct mtd_oob_buf64 buf;
 791		struct mtd_oob_buf64 __user *buf_user = argp;
 792
 793		if (copy_from_user(&buf, argp, sizeof(buf)))
 794			ret = -EFAULT;
 795		else
 796			ret = mtdchar_readoob(file, mtd, buf.start, buf.length,
 797				(void __user *)(uintptr_t)buf.usr_ptr,
 798				&buf_user->length);
 799		break;
 800	}
 801
 802	case MEMWRITE:
 803	{
 804		ret = mtdchar_write_ioctl(mtd,
 805		      (struct mtd_write_req __user *)arg);
 806		break;
 807	}
 808
 809	case MEMLOCK:
 810	{
 811		struct erase_info_user einfo;
 812
 813		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 814			return -EFAULT;
 815
 816		ret = mtd_lock(mtd, einfo.start, einfo.length);
 817		break;
 818	}
 819
 820	case MEMUNLOCK:
 821	{
 822		struct erase_info_user einfo;
 823
 824		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 825			return -EFAULT;
 826
 827		ret = mtd_unlock(mtd, einfo.start, einfo.length);
 828		break;
 829	}
 830
 831	case MEMISLOCKED:
 832	{
 833		struct erase_info_user einfo;
 834
 835		if (copy_from_user(&einfo, argp, sizeof(einfo)))
 836			return -EFAULT;
 837
 838		ret = mtd_is_locked(mtd, einfo.start, einfo.length);
 839		break;
 840	}
 841
 842	/* Legacy interface */
 843	case MEMGETOOBSEL:
 844	{
 845		struct nand_oobinfo oi;
 846
 847		if (!mtd->ecclayout)
 848			return -EOPNOTSUPP;
 849		if (mtd->ecclayout->eccbytes > ARRAY_SIZE(oi.eccpos))
 850			return -EINVAL;
 851
 852		oi.useecc = MTD_NANDECC_AUTOPLACE;
 853		memcpy(&oi.eccpos, mtd->ecclayout->eccpos, sizeof(oi.eccpos));
 854		memcpy(&oi.oobfree, mtd->ecclayout->oobfree,
 855		       sizeof(oi.oobfree));
 856		oi.eccbytes = mtd->ecclayout->eccbytes;
 857
 858		if (copy_to_user(argp, &oi, sizeof(struct nand_oobinfo)))
 859			return -EFAULT;
 860		break;
 861	}
 862
 863	case MEMGETBADBLOCK:
 864	{
 865		loff_t offs;
 866
 867		if (copy_from_user(&offs, argp, sizeof(loff_t)))
 868			return -EFAULT;
 869		return mtd_block_isbad(mtd, offs);
 870		break;
 871	}
 872
 873	case MEMSETBADBLOCK:
 874	{
 875		loff_t offs;
 876
 877		if (copy_from_user(&offs, argp, sizeof(loff_t)))
 878			return -EFAULT;
 879		return mtd_block_markbad(mtd, offs);
 880		break;
 881	}
 882
 883	case OTPSELECT:
 884	{
 885		int mode;
 886		if (copy_from_user(&mode, argp, sizeof(int)))
 887			return -EFAULT;
 888
 889		mfi->mode = MTD_FILE_MODE_NORMAL;
 890
 891		ret = otp_select_filemode(mfi, mode);
 892
 893		file->f_pos = 0;
 894		break;
 895	}
 896
 897	case OTPGETREGIONCOUNT:
 898	case OTPGETREGIONINFO:
 899	{
 900		struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
 901		size_t retlen;
 902		if (!buf)
 903			return -ENOMEM;
 904		switch (mfi->mode) {
 905		case MTD_FILE_MODE_OTP_FACTORY:
 906			ret = mtd_get_fact_prot_info(mtd, 4096, &retlen, buf);
 907			break;
 908		case MTD_FILE_MODE_OTP_USER:
 909			ret = mtd_get_user_prot_info(mtd, 4096, &retlen, buf);
 910			break;
 911		default:
 912			ret = -EINVAL;
 913			break;
 914		}
 915		if (!ret) {
 916			if (cmd == OTPGETREGIONCOUNT) {
 917				int nbr = retlen / sizeof(struct otp_info);
 918				ret = copy_to_user(argp, &nbr, sizeof(int));
 919			} else
 920				ret = copy_to_user(argp, buf, retlen);
 921			if (ret)
 922				ret = -EFAULT;
 923		}
 924		kfree(buf);
 925		break;
 926	}
 927
 928	case OTPLOCK:
 929	{
 930		struct otp_info oinfo;
 931
 932		if (mfi->mode != MTD_FILE_MODE_OTP_USER)
 933			return -EINVAL;
 934		if (copy_from_user(&oinfo, argp, sizeof(oinfo)))
 935			return -EFAULT;
 936		ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 937		break;
 938	}
 939
 940	/* This ioctl is being deprecated - it truncates the ECC layout */
 941	case ECCGETLAYOUT:
 942	{
 943		struct nand_ecclayout_user *usrlay;
 944
 945		if (!mtd->ecclayout)
 946			return -EOPNOTSUPP;
 947
 948		usrlay = kmalloc(sizeof(*usrlay), GFP_KERNEL);
 949		if (!usrlay)
 950			return -ENOMEM;
 951
 952		shrink_ecclayout(mtd->ecclayout, usrlay);
 953
 954		if (copy_to_user(argp, usrlay, sizeof(*usrlay)))
 955			ret = -EFAULT;
 956		kfree(usrlay);
 957		break;
 958	}
 959
 960	case ECCGETSTATS:
 961	{
 962		if (copy_to_user(argp, &mtd->ecc_stats,
 963				 sizeof(struct mtd_ecc_stats)))
 964			return -EFAULT;
 965		break;
 966	}
 967
 968	case MTDFILEMODE:
 969	{
 970		mfi->mode = 0;
 971
 972		switch(arg) {
 973		case MTD_FILE_MODE_OTP_FACTORY:
 974		case MTD_FILE_MODE_OTP_USER:
 975			ret = otp_select_filemode(mfi, arg);
 976			break;
 977
 978		case MTD_FILE_MODE_RAW:
 979			if (!mtd_has_oob(mtd))
 980				return -EOPNOTSUPP;
 981			mfi->mode = arg;
 982
 983		case MTD_FILE_MODE_NORMAL:
 984			break;
 985		default:
 986			ret = -EINVAL;
 987		}
 988		file->f_pos = 0;
 989		break;
 990	}
 991
 992	case BLKPG:
 993	{
 994		ret = mtdchar_blkpg_ioctl(mtd,
 995		      (struct blkpg_ioctl_arg __user *)arg);
 
 
 
 
 
 996		break;
 997	}
 998
 999	case BLKRRPART:
1000	{
1001		/* No reread partition feature. Just return ok */
1002		ret = 0;
1003		break;
1004	}
1005
1006	default:
1007		ret = -ENOTTY;
1008	}
1009
1010	return ret;
1011} /* memory_ioctl */
1012
1013static long mtdchar_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1014{
1015	int ret;
1016
1017	mutex_lock(&mtd_mutex);
1018	ret = mtdchar_ioctl(file, cmd, arg);
1019	mutex_unlock(&mtd_mutex);
1020
1021	return ret;
1022}
1023
1024#ifdef CONFIG_COMPAT
1025
1026struct mtd_oob_buf32 {
1027	u_int32_t start;
1028	u_int32_t length;
1029	compat_caddr_t ptr;	/* unsigned char* */
1030};
1031
1032#define MEMWRITEOOB32		_IOWR('M', 3, struct mtd_oob_buf32)
1033#define MEMREADOOB32		_IOWR('M', 4, struct mtd_oob_buf32)
1034
1035static long mtdchar_compat_ioctl(struct file *file, unsigned int cmd,
1036	unsigned long arg)
1037{
1038	struct mtd_file_info *mfi = file->private_data;
1039	struct mtd_info *mtd = mfi->mtd;
1040	void __user *argp = compat_ptr(arg);
1041	int ret = 0;
1042
1043	mutex_lock(&mtd_mutex);
1044
1045	switch (cmd) {
1046	case MEMWRITEOOB32:
1047	{
1048		struct mtd_oob_buf32 buf;
1049		struct mtd_oob_buf32 __user *buf_user = argp;
1050
1051		if (copy_from_user(&buf, argp, sizeof(buf)))
1052			ret = -EFAULT;
1053		else
1054			ret = mtdchar_writeoob(file, mtd, buf.start,
1055				buf.length, compat_ptr(buf.ptr),
1056				&buf_user->length);
1057		break;
1058	}
1059
1060	case MEMREADOOB32:
1061	{
1062		struct mtd_oob_buf32 buf;
1063		struct mtd_oob_buf32 __user *buf_user = argp;
1064
1065		/* NOTE: writes return length to buf->start */
1066		if (copy_from_user(&buf, argp, sizeof(buf)))
1067			ret = -EFAULT;
1068		else
1069			ret = mtdchar_readoob(file, mtd, buf.start,
1070				buf.length, compat_ptr(buf.ptr),
1071				&buf_user->start);
1072		break;
1073	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1074	default:
1075		ret = mtdchar_ioctl(file, cmd, (unsigned long)argp);
1076	}
1077
1078	mutex_unlock(&mtd_mutex);
1079
1080	return ret;
1081}
1082
1083#endif /* CONFIG_COMPAT */
1084
1085/*
1086 * try to determine where a shared mapping can be made
1087 * - only supported for NOMMU at the moment (MMU can't doesn't copy private
1088 *   mappings)
1089 */
1090#ifndef CONFIG_MMU
1091static unsigned long mtdchar_get_unmapped_area(struct file *file,
1092					   unsigned long addr,
1093					   unsigned long len,
1094					   unsigned long pgoff,
1095					   unsigned long flags)
1096{
1097	struct mtd_file_info *mfi = file->private_data;
1098	struct mtd_info *mtd = mfi->mtd;
1099	unsigned long offset;
1100	int ret;
1101
1102	if (addr != 0)
1103		return (unsigned long) -EINVAL;
1104
1105	if (len > mtd->size || pgoff >= (mtd->size >> PAGE_SHIFT))
1106		return (unsigned long) -EINVAL;
1107
1108	offset = pgoff << PAGE_SHIFT;
1109	if (offset > mtd->size - len)
1110		return (unsigned long) -EINVAL;
1111
1112	ret = mtd_get_unmapped_area(mtd, len, offset, flags);
1113	return ret == -EOPNOTSUPP ? -ENODEV : ret;
1114}
 
 
 
 
 
 
 
1115#endif
1116
1117/*
1118 * set up a mapping for shared memory segments
1119 */
1120static int mtdchar_mmap(struct file *file, struct vm_area_struct *vma)
1121{
1122#ifdef CONFIG_MMU
1123	struct mtd_file_info *mfi = file->private_data;
1124	struct mtd_info *mtd = mfi->mtd;
1125	struct map_info *map = mtd->priv;
1126
1127        /* This is broken because it assumes the MTD device is map-based
1128	   and that mtd->priv is a valid struct map_info.  It should be
1129	   replaced with something that uses the mtd_get_unmapped_area()
1130	   operation properly. */
1131	if (0 /*mtd->type == MTD_RAM || mtd->type == MTD_ROM*/) {
1132#ifdef pgprot_noncached
1133		if (file->f_flags & O_DSYNC || map->phys >= __pa(high_memory))
1134			vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
1135#endif
1136		return vm_iomap_memory(vma, map->phys, map->size);
1137	}
1138	return -ENODEV;
1139#else
1140	return vma->vm_flags & VM_SHARED ? 0 : -EACCES;
1141#endif
1142}
1143
1144static const struct file_operations mtd_fops = {
1145	.owner		= THIS_MODULE,
1146	.llseek		= mtdchar_lseek,
1147	.read		= mtdchar_read,
1148	.write		= mtdchar_write,
1149	.unlocked_ioctl	= mtdchar_unlocked_ioctl,
1150#ifdef CONFIG_COMPAT
1151	.compat_ioctl	= mtdchar_compat_ioctl,
1152#endif
1153	.open		= mtdchar_open,
1154	.release	= mtdchar_close,
1155	.mmap		= mtdchar_mmap,
1156#ifndef CONFIG_MMU
1157	.get_unmapped_area = mtdchar_get_unmapped_area,
 
1158#endif
1159};
1160
1161static const struct super_operations mtd_ops = {
1162	.drop_inode = generic_delete_inode,
1163	.statfs = simple_statfs,
1164};
1165
1166static struct dentry *mtd_inodefs_mount(struct file_system_type *fs_type,
1167				int flags, const char *dev_name, void *data)
1168{
1169	return mount_pseudo(fs_type, "mtd_inode:", &mtd_ops, NULL, MTD_INODE_FS_MAGIC);
1170}
1171
1172static struct file_system_type mtd_inodefs_type = {
1173       .name = "mtd_inodefs",
1174       .mount = mtd_inodefs_mount,
1175       .kill_sb = kill_anon_super,
1176};
1177MODULE_ALIAS_FS("mtd_inodefs");
1178
1179int __init init_mtdchar(void)
1180{
1181	int ret;
1182
1183	ret = __register_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS,
1184				   "mtd", &mtd_fops);
1185	if (ret < 0) {
1186		pr_err("Can't allocate major number %d for MTD\n",
1187		       MTD_CHAR_MAJOR);
1188		return ret;
1189	}
1190
1191	ret = register_filesystem(&mtd_inodefs_type);
1192	if (ret) {
1193		pr_err("Can't register mtd_inodefs filesystem, error %d\n",
1194		       ret);
1195		goto err_unregister_chdev;
1196	}
1197
1198	return ret;
1199
1200err_unregister_chdev:
1201	__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1202	return ret;
1203}
1204
1205void __exit cleanup_mtdchar(void)
1206{
1207	unregister_filesystem(&mtd_inodefs_type);
1208	__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
1209}
1210
1211MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);