[deliverable/linux.git] / drivers / mtd / mtdchar.c

/*
 * $Id: mtdchar.c,v 1.73 2005/07/04 17:36:41 gleixner Exp $
 *
 * Character-device access to raw MTD devices.
 *
 */

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/compatmac.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <asm/uaccess.h>

#include <linux/device.h>

static struct class *mtd_class;

static void mtd_notify_add(struct mtd_info* mtd)
{
	if (!mtd)
		return;

	class_device_create(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
			    NULL, "mtd%d", mtd->index);
	
	class_device_create(mtd_class, 
			    MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
			    NULL, "mtd%dro", mtd->index);
}

static void mtd_notify_remove(struct mtd_info* mtd)
{
	if (!mtd)
		return;

	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
}

static struct mtd_notifier notifier = {
	.add	= mtd_notify_add,
	.remove	= mtd_notify_remove,
};

/*
 * We use file->private_data to store a pointer to the MTDdevice.
 * Since alighment is at least 32 bits, we have 2 bits free for OTP
 * modes as well.
 */

#define TO_MTD(file) (struct mtd_info *)((long)((file)->private_data) & ~3L)

#define MTD_MODE_OTP_FACT	1
#define MTD_MODE_OTP_USER	2
#define MTD_MODE(file)		((long)((file)->private_data) & 3)

#define SET_MTD_MODE(file, mode) \
	do { long __p = (long)((file)->private_data); \
	     (file)->private_data = (void *)((__p & ~3L) | mode); } while (0)

static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
{
	struct mtd_info *mtd = TO_MTD(file);

	switch (orig) {
	case 0:
		/* SEEK_SET */
		file->f_pos = offset;
		break;
	case 1:
		/* SEEK_CUR */
		file->f_pos += offset;
		break;
	case 2:
		/* SEEK_END */
		file->f_pos =mtd->size + offset;
		break;
	default:
		return -EINVAL;
	}

	if (file->f_pos < 0)
		file->f_pos = 0;
	else if (file->f_pos >= mtd->size)
		file->f_pos = mtd->size - 1;

	return file->f_pos;
}


static int mtd_open(struct inode *inode, struct file *file)
{
	int minor = iminor(inode);
	int devnum = minor >> 1;
	struct mtd_info *mtd;

	DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");

	if (devnum >= MAX_MTD_DEVICES)
		return -ENODEV;

	/* You can't open the RO devices RW */
	if ((file->f_mode & 2) && (minor & 1))
		return -EACCES;

	mtd = get_mtd_device(NULL, devnum);
	
	if (!mtd)
		return -ENODEV;
	
	if (MTD_ABSENT == mtd->type) {
		put_mtd_device(mtd);
		return -ENODEV;
	}

	file->private_data = mtd;
		
	/* You can't open it RW if it's not a writeable device */
	if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
		put_mtd_device(mtd);
		return -EACCES;
	}
		
	return 0;
} /* mtd_open */

/*====================================================================*/

static int mtd_close(struct inode *inode, struct file *file)
{
	struct mtd_info *mtd;

	DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");

	mtd = TO_MTD(file);
	
	if (mtd->sync)
		mtd->sync(mtd);
	
	put_mtd_device(mtd);

	return 0;
} /* mtd_close */

/* FIXME: This _really_ needs to die. In 2.5, we should lock the
   userspace buffer down and use it directly with readv/writev.
*/
#define MAX_KMALLOC_SIZE 0x20000

static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
{
	struct mtd_info *mtd = TO_MTD(file);
	size_t retlen=0;
	size_t total_retlen=0;
	int ret=0;
	int len;
	char *kbuf;
	
	DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");

	if (*ppos + count > mtd->size)
		count = mtd->size - *ppos;

	if (!count)
		return 0;
	
	/* FIXME: Use kiovec in 2.5 to lock down the user's buffers
	   and pass them directly to the MTD functions */
	while (count) {
		if (count > MAX_KMALLOC_SIZE) 
			len = MAX_KMALLOC_SIZE;
		else
			len = count;

		kbuf=kmalloc(len,GFP_KERNEL);
		if (!kbuf)
			return -ENOMEM;
		
		switch (MTD_MODE(file)) {
		case MTD_MODE_OTP_FACT:
			ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
			break;
		case MTD_MODE_OTP_USER:
			ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
			break;
		default:
			ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
		}
		/* Nand returns -EBADMSG on ecc errors, but it returns
		 * the data. For our userspace tools it is important
		 * to dump areas with ecc errors ! 
		 * Userspace software which accesses NAND this way
		 * must be aware of the fact that it deals with NAND
		 */
		if (!ret || (ret == -EBADMSG)) {
			*ppos += retlen;
			if (copy_to_user(buf, kbuf, retlen)) {
			        kfree(kbuf);
				return -EFAULT;
			}
			else
				total_retlen += retlen;

			count -= retlen;
			buf += retlen;
			if (retlen == 0)
				count = 0;
		}
		else {
			kfree(kbuf);
			return ret;
		}
		
		kfree(kbuf);
	}

	return total_retlen;
} /* mtd_read */

static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
{
	struct mtd_info *mtd = TO_MTD(file);
	char *kbuf;
	size_t retlen;
	size_t total_retlen=0;
	int ret=0;
	int len;

	DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
	
	if (*ppos == mtd->size)
		return -ENOSPC;
	
	if (*ppos + count > mtd->size)
		count = mtd->size - *ppos;

	if (!count)
		return 0;

	while (count) {
		if (count > MAX_KMALLOC_SIZE) 
			len = MAX_KMALLOC_SIZE;
		else
			len = count;

		kbuf=kmalloc(len,GFP_KERNEL);
		if (!kbuf) {
			printk("kmalloc is null\n");
			return -ENOMEM;
		}

		if (copy_from_user(kbuf, buf, len)) {
			kfree(kbuf);
			return -EFAULT;
		}
		
		switch (MTD_MODE(file)) {
		case MTD_MODE_OTP_FACT:
			ret = -EROFS;
			break;
		case MTD_MODE_OTP_USER:
			if (!mtd->write_user_prot_reg) {
				ret = -EOPNOTSUPP;
				break;
			}
			ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
			break;
		default:
			ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
		}
		if (!ret) {
			*ppos += retlen;
			total_retlen += retlen;
			count -= retlen;
			buf += retlen;
		}
		else {
			kfree(kbuf);
			return ret;
		}
		
		kfree(kbuf);
	}

	return total_retlen;
} /* mtd_write */

/*======================================================================

    IOCTL calls for getting device parameters.

======================================================================*/
static void mtdchar_erase_callback (struct erase_info *instr)
{
	wake_up((wait_queue_head_t *)instr->priv);
}

static int mtd_ioctl(struct inode *inode, struct file *file,
		     u_int cmd, u_long arg)
{
	struct mtd_info *mtd = TO_MTD(file);
	void __user *argp = (void __user *)arg;
	int ret = 0;
	u_long size;
	
	DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");

	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
	if (cmd & IOC_IN) {
		if (!access_ok(VERIFY_READ, argp, size))
			return -EFAULT;
	}
	if (cmd & IOC_OUT) {
		if (!access_ok(VERIFY_WRITE, argp, size))
			return -EFAULT;
	}
	
	switch (cmd) {
	case MEMGETREGIONCOUNT:
		if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
			return -EFAULT;
		break;

	case MEMGETREGIONINFO:
	{
		struct region_info_user ur;

		if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
			return -EFAULT;

		if (ur.regionindex >= mtd->numeraseregions)
			return -EINVAL;
		if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
				sizeof(struct mtd_erase_region_info)))
			return -EFAULT;
		break;
	}

	case MEMGETINFO:
		if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
			return -EFAULT;
		break;

	case MEMERASE:
	{
		struct erase_info *erase;

		if(!(file->f_mode & 2))
			return -EPERM;

		erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
		if (!erase)
			ret = -ENOMEM;
		else {
			wait_queue_head_t waitq;
			DECLARE_WAITQUEUE(wait, current);

			init_waitqueue_head(&waitq);

			memset (erase,0,sizeof(struct erase_info));
			if (copy_from_user(&erase->addr, argp,
				    sizeof(struct erase_info_user))) {
				kfree(erase);
				return -EFAULT;
			}
			erase->mtd = mtd;
			erase->callback = mtdchar_erase_callback;
			erase->priv = (unsigned long)&waitq;
			
			/*
			  FIXME: Allow INTERRUPTIBLE. Which means
			  not having the wait_queue head on the stack.
			  
			  If the wq_head is on the stack, and we
			  leave because we got interrupted, then the
			  wq_head is no longer there when the
			  callback routine tries to wake us up.
			*/
			ret = mtd->erase(mtd, erase);
			if (!ret) {
				set_current_state(TASK_UNINTERRUPTIBLE);
				add_wait_queue(&waitq, &wait);
				if (erase->state != MTD_ERASE_DONE &&
				    erase->state != MTD_ERASE_FAILED)
					schedule();
				remove_wait_queue(&waitq, &wait);
				set_current_state(TASK_RUNNING);

				ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
			}
			kfree(erase);
		}
		break;
	}

	case MEMWRITEOOB:
	{
		struct mtd_oob_buf buf;
		void *databuf;
		ssize_t retlen;
		
		if(!(file->f_mode & 2))
			return -EPERM;

		if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
			return -EFAULT;
		
		if (buf.length > 0x4096)
			return -EINVAL;

		if (!mtd->write_oob)
			ret = -EOPNOTSUPP;
		else
			ret = access_ok(VERIFY_READ, buf.ptr,
					buf.length) ? 0 : EFAULT;

		if (ret)
			return ret;

		databuf = kmalloc(buf.length, GFP_KERNEL);
		if (!databuf)
			return -ENOMEM;
		
		if (copy_from_user(databuf, buf.ptr, buf.length)) {
			kfree(databuf);
			return -EFAULT;
		}

		ret = (mtd->write_oob)(mtd, buf.start, buf.length, &retlen, databuf);

		if (copy_to_user(argp + sizeof(uint32_t), &retlen, sizeof(uint32_t)))
			ret = -EFAULT;

		kfree(databuf);
		break;

	}

	case MEMREADOOB:
	{
		struct mtd_oob_buf buf;
		void *databuf;
		ssize_t retlen;

		if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
			return -EFAULT;
		
		if (buf.length > 0x4096)
			return -EINVAL;

		if (!mtd->read_oob)
			ret = -EOPNOTSUPP;
		else
			ret = access_ok(VERIFY_WRITE, buf.ptr,
					buf.length) ? 0 : -EFAULT;

		if (ret)
			return ret;

		databuf = kmalloc(buf.length, GFP_KERNEL);
		if (!databuf)
			return -ENOMEM;
		
		ret = (mtd->read_oob)(mtd, buf.start, buf.length, &retlen, databuf);

		if (put_user(retlen, (uint32_t __user *)argp))
			ret = -EFAULT;
		else if (retlen && copy_to_user(buf.ptr, databuf, retlen))
			ret = -EFAULT;
		
		kfree(databuf);
		break;
	}

	case MEMLOCK:
	{
		struct erase_info_user info;

		if (copy_from_user(&info, argp, sizeof(info)))
			return -EFAULT;

		if (!mtd->lock)
			ret = -EOPNOTSUPP;
		else
			ret = mtd->lock(mtd, info.start, info.length);
		break;
	}

	case MEMUNLOCK:
	{
		struct erase_info_user info;

		if (copy_from_user(&info, argp, sizeof(info)))
			return -EFAULT;

		if (!mtd->unlock)
			ret = -EOPNOTSUPP;
		else
			ret = mtd->unlock(mtd, info.start, info.length);
		break;
	}

	case MEMSETOOBSEL:
	{
		if (copy_from_user(&mtd->oobinfo, argp, sizeof(struct nand_oobinfo)))
			return -EFAULT;
		break;
	}

	case MEMGETOOBSEL:
	{
		if (copy_to_user(argp, &(mtd->oobinfo), sizeof(struct nand_oobinfo)))
			return -EFAULT;
		break;
	}

	case MEMGETBADBLOCK:
	{
		loff_t offs;
		
		if (copy_from_user(&offs, argp, sizeof(loff_t)))
			return -EFAULT;
		if (!mtd->block_isbad)
			ret = -EOPNOTSUPP;
		else
			return mtd->block_isbad(mtd, offs);
		break;
	}

	case MEMSETBADBLOCK:
	{
		loff_t offs;

		if (copy_from_user(&offs, argp, sizeof(loff_t)))
			return -EFAULT;
		if (!mtd->block_markbad)
			ret = -EOPNOTSUPP;
		else
			return mtd->block_markbad(mtd, offs);
		break;
	}

#ifdef CONFIG_MTD_OTP
	case OTPSELECT:
	{
		int mode;
		if (copy_from_user(&mode, argp, sizeof(int)))
			return -EFAULT;
		SET_MTD_MODE(file, 0);
		switch (mode) {
		case MTD_OTP_FACTORY:
			if (!mtd->read_fact_prot_reg)
				ret = -EOPNOTSUPP;
			else
				SET_MTD_MODE(file, MTD_MODE_OTP_FACT);
			break;
		case MTD_OTP_USER:
			if (!mtd->read_fact_prot_reg)
				ret = -EOPNOTSUPP;
			else
				SET_MTD_MODE(file, MTD_MODE_OTP_USER);
			break;
		default:
			ret = -EINVAL;
		case MTD_OTP_OFF:
			break;
		}
		file->f_pos = 0;
		break;
	}

	case OTPGETREGIONCOUNT:
	case OTPGETREGIONINFO:
	{
		struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
		if (!buf)
			return -ENOMEM;
		ret = -EOPNOTSUPP;
		switch (MTD_MODE(file)) {
		case MTD_MODE_OTP_FACT:
			if (mtd->get_fact_prot_info)
				ret = mtd->get_fact_prot_info(mtd, buf, 4096);
			break;
		case MTD_MODE_OTP_USER:
			if (mtd->get_user_prot_info)
				ret = mtd->get_user_prot_info(mtd, buf, 4096);
			break;
		}
		if (ret >= 0) {
			if (cmd == OTPGETREGIONCOUNT) {
				int nbr = ret / sizeof(struct otp_info);
				ret = copy_to_user(argp, &nbr, sizeof(int));
			} else
				ret = copy_to_user(argp, buf, ret);
			if (ret)
				ret = -EFAULT;
		}
		kfree(buf);
		break;
	}

	case OTPLOCK:
	{
		struct otp_info info;

		if (MTD_MODE(file) != MTD_MODE_OTP_USER)
			return -EINVAL;
		if (copy_from_user(&info, argp, sizeof(info)))
			return -EFAULT;
		if (!mtd->lock_user_prot_reg)
			return -EOPNOTSUPP;
		ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
		break;
	}
#endif

	default:
		ret = -ENOTTY;
	}

	return ret;
} /* memory_ioctl */

static struct file_operations mtd_fops = {
	.owner		= THIS_MODULE,
	.llseek		= mtd_lseek,
	.read		= mtd_read,
	.write		= mtd_write,
	.ioctl		= mtd_ioctl,
	.open		= mtd_open,
	.release	= mtd_close,
};

static int __init init_mtdchar(void)
{
	if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
		printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
		       MTD_CHAR_MAJOR);
		return -EAGAIN;
	}

	mtd_class = class_create(THIS_MODULE, "mtd");

	if (IS_ERR(mtd_class)) {
		printk(KERN_ERR "Error creating mtd class.\n");
		unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
		return PTR_ERR(mtd_class);
	}

	register_mtd_user(&notifier);
	return 0;
}

static void __exit cleanup_mtdchar(void)
{
	unregister_mtd_user(&notifier);
	class_destroy(mtd_class);
	unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
}

module_init(init_mtdchar);
module_exit(cleanup_mtdchar);


MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Direct character-device access to MTD devices");
Commit	Line	Data
1da177e4	1	/*
3a7a8824	2	* $Id: mtdchar.c,v 1.73 2005/07/04 17:36:41 gleixner Exp $
1da177e4 LT	3	*
	4	* Character-device access to raw MTD devices.
	5	*
	6	*/
	7
	8	#include <linux/config.h>
	9	#include <linux/kernel.h>
	10	#include <linux/module.h>
	11	#include <linux/mtd/mtd.h>
	12	#include <linux/mtd/compatmac.h>
	13	#include <linux/slab.h>
	14	#include <linux/init.h>
	15	#include <linux/fs.h>
	16	#include <asm/uaccess.h>
	17
9bc7b387 TP	18	#include <linux/device.h>
	19
	20	static struct class *mtd_class;
1da177e4 LT	21
	22	static void mtd_notify_add(struct mtd_info* mtd)
	23	{
	24	if (!mtd)
	25	return;
	26
9bc7b387 TP	27	class_device_create(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
	28	NULL, "mtd%d", mtd->index);
	29
	30	class_device_create(mtd_class,
	31	MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
	32	NULL, "mtd%dro", mtd->index);
1da177e4 LT	33	}
	34
	35	static void mtd_notify_remove(struct mtd_info* mtd)
	36	{
	37	if (!mtd)
	38	return;
9bc7b387 TP	39
	40	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
	41	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
1da177e4 LT	42	}
	43
	44	static struct mtd_notifier notifier = {
	45	.add = mtd_notify_add,
	46	.remove = mtd_notify_remove,
	47	};
	48
045e9a5d NP	49	/*
	50	* We use file->private_data to store a pointer to the MTDdevice.
	51	* Since alighment is at least 32 bits, we have 2 bits free for OTP
	52	* modes as well.
	53	*/
	54
	55	#define TO_MTD(file) (struct mtd_info *)((long)((file)->private_data) & ~3L)
31f4233b	56
045e9a5d NP	57	#define MTD_MODE_OTP_FACT 1
	58	#define MTD_MODE_OTP_USER 2
	59	#define MTD_MODE(file) ((long)((file)->private_data) & 3)
	60
	61	#define SET_MTD_MODE(file, mode) \
	62	do { long __p = (long)((file)->private_data); \
	63	(file)->private_data = (void *)((__p & ~3L) \| mode); } while (0)
31f4233b	64
1da177e4 LT	65	static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
1da177e4 LT	66	{
045e9a5d	67	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	68
	69	switch (orig) {
	70	case 0:
	71	/* SEEK_SET */
	72	file->f_pos = offset;
	73	break;
	74	case 1:
	75	/* SEEK_CUR */
	76	file->f_pos += offset;
	77	break;
	78	case 2:
	79	/* SEEK_END */
	80	file->f_pos =mtd->size + offset;
	81	break;
	82	default:
	83	return -EINVAL;
	84	}
	85
	86	if (file->f_pos < 0)
	87	file->f_pos = 0;
	88	else if (file->f_pos >= mtd->size)
	89	file->f_pos = mtd->size - 1;
	90
	91	return file->f_pos;
	92	}
	93
	94
	95
	96	static int mtd_open(struct inode inode, struct file file)
	97	{
	98	int minor = iminor(inode);
	99	int devnum = minor >> 1;
	100	struct mtd_info *mtd;
	101
	102	DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
	103
	104	if (devnum >= MAX_MTD_DEVICES)
	105	return -ENODEV;
	106
	107	/* You can't open the RO devices RW */
	108	if ((file->f_mode & 2) && (minor & 1))
	109	return -EACCES;
	110
	111	mtd = get_mtd_device(NULL, devnum);
	112
	113	if (!mtd)
	114	return -ENODEV;
	115
	116	if (MTD_ABSENT == mtd->type) {
	117	put_mtd_device(mtd);
	118	return -ENODEV;
	119	}
	120
	121	file->private_data = mtd;
	122
	123	/* You can't open it RW if it's not a writeable device */
	124	if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
	125	put_mtd_device(mtd);
	126	return -EACCES;
	127	}
	128
	129	return 0;
	130	} /* mtd_open */
	131
132	/====================================================================/
133
134	static int mtd_close(struct inode inode, struct file file)
135	{
136	struct mtd_info *mtd;
137
138	DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
139
045e9a5d	140	mtd = TO_MTD(file);
1da177e4 LT	141
	142	if (mtd->sync)
	143	mtd->sync(mtd);
	144
	145	put_mtd_device(mtd);
	146
	147	return 0;
	148	} /* mtd_close */
	149
	150	/* FIXME: This _really_ needs to die. In 2.5, we should lock the
	151	userspace buffer down and use it directly with readv/writev.
	152	*/
	153	#define MAX_KMALLOC_SIZE 0x20000
	154
	155	static ssize_t mtd_read(struct file file, char __user buf, size_t count,loff_t *ppos)
	156	{
045e9a5d	157	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	158	size_t retlen=0;
	159	size_t total_retlen=0;
	160	int ret=0;
	161	int len;
	162	char *kbuf;
	163
	164	DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
	165
	166	if (*ppos + count > mtd->size)
	167	count = mtd->size - *ppos;
	168
	169	if (!count)
	170	return 0;
	171
	172	/* FIXME: Use kiovec in 2.5 to lock down the user's buffers
	173	and pass them directly to the MTD functions */
	174	while (count) {
	175	if (count > MAX_KMALLOC_SIZE)
	176	len = MAX_KMALLOC_SIZE;
	177	else
	178	len = count;
	179
	180	kbuf=kmalloc(len,GFP_KERNEL);
	181	if (!kbuf)
	182	return -ENOMEM;
	183
045e9a5d	184	switch (MTD_MODE(file)) {
31f4233b NP	185	case MTD_MODE_OTP_FACT:
	186	ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	187	break;
	188	case MTD_MODE_OTP_USER:
	189	ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	190	break;
	191	default:
	192	ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
	193	}
1da177e4 LT	194	/* Nand returns -EBADMSG on ecc errors, but it returns
	195	* the data. For our userspace tools it is important
	196	* to dump areas with ecc errors !
	197	* Userspace software which accesses NAND this way
	198	* must be aware of the fact that it deals with NAND
	199	*/
	200	if (!ret \|\| (ret == -EBADMSG)) {
	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;
31f4233b NP	211	if (retlen == 0)
31f4233b NP	212	count = 0;
1da177e4 LT	213	}
	214	else {
	215	kfree(kbuf);
	216	return ret;
	217	}
	218
	219	kfree(kbuf);
	220	}
	221
	222	return total_retlen;
	223	} /* mtd_read */
	224
	225	static ssize_t mtd_write(struct file file, const char __user buf, size_t count,loff_t *ppos)
	226	{
045e9a5d	227	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	228	char *kbuf;
	229	size_t retlen;
	230	size_t total_retlen=0;
	231	int ret=0;
	232	int len;
	233
	234	DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
	235
	236	if (*ppos == mtd->size)
	237	return -ENOSPC;
	238
	239	if (*ppos + count > mtd->size)
	240	count = mtd->size - *ppos;
	241
	242	if (!count)
	243	return 0;
	244
	245	while (count) {
	246	if (count > MAX_KMALLOC_SIZE)
	247	len = MAX_KMALLOC_SIZE;
	248	else
	249	len = count;
	250
	251	kbuf=kmalloc(len,GFP_KERNEL);
	252	if (!kbuf) {
	253	printk("kmalloc is null\n");
	254	return -ENOMEM;
	255	}
	256
	257	if (copy_from_user(kbuf, buf, len)) {
	258	kfree(kbuf);
	259	return -EFAULT;
	260	}
	261
045e9a5d	262	switch (MTD_MODE(file)) {
31f4233b NP	263	case MTD_MODE_OTP_FACT:
	264	ret = -EROFS;
	265	break;
	266	case MTD_MODE_OTP_USER:
	267	if (!mtd->write_user_prot_reg) {
	268	ret = -EOPNOTSUPP;
	269	break;
	270	}
	271	ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	272	break;
	273	default:
	274	ret = ((mtd->write))(mtd, ppos, len, &retlen, kbuf);
	275	}
1da177e4 LT	276	if (!ret) {
	277	*ppos += retlen;
	278	total_retlen += retlen;
	279	count -= retlen;
	280	buf += retlen;
	281	}
	282	else {
	283	kfree(kbuf);
	284	return ret;
	285	}
	286
	287	kfree(kbuf);
	288	}
	289
	290	return total_retlen;
	291	} /* mtd_write */
	292
	293	/*======================================================================
	294
	295	IOCTL calls for getting device parameters.
	296
	297	======================================================================*/
	298	static void mtdchar_erase_callback (struct erase_info *instr)
	299	{
	300	wake_up((wait_queue_head_t *)instr->priv);
	301	}
	302
	303	static int mtd_ioctl(struct inode inode, struct file file,
	304	u_int cmd, u_long arg)
	305	{
045e9a5d	306	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	307	void __user argp = (void __user )arg;
	308	int ret = 0;
	309	u_long size;
	310
	311	DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
	312
	313	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
	314	if (cmd & IOC_IN) {
	315	if (!access_ok(VERIFY_READ, argp, size))
	316	return -EFAULT;
	317	}
	318	if (cmd & IOC_OUT) {
	319	if (!access_ok(VERIFY_WRITE, argp, size))
	320	return -EFAULT;
	321	}
	322
	323	switch (cmd) {
	324	case MEMGETREGIONCOUNT:
	325	if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
	326	return -EFAULT;
	327	break;
	328
	329	case MEMGETREGIONINFO:
	330	{
	331	struct region_info_user ur;
	332
	333	if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
	334	return -EFAULT;
	335
	336	if (ur.regionindex >= mtd->numeraseregions)
	337	return -EINVAL;
	338	if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
	339	sizeof(struct mtd_erase_region_info)))
	340	return -EFAULT;
	341	break;
	342	}
	343
	344	case MEMGETINFO:
	345	if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
	346	return -EFAULT;
	347	break;
	348
	349	case MEMERASE:
	350	{
	351	struct erase_info *erase;
	352
	353	if(!(file->f_mode & 2))
	354	return -EPERM;
	355
	356	erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
	357	if (!erase)
	358	ret = -ENOMEM;
	359	else {
	360	wait_queue_head_t waitq;
	361	DECLARE_WAITQUEUE(wait, current);
	362
	363	init_waitqueue_head(&waitq);
	364
	365	memset (erase,0,sizeof(struct erase_info));
	366	if (copy_from_user(&erase->addr, argp,
	367	sizeof(struct erase_info_user))) {
	368	kfree(erase);
	369	return -EFAULT;
	370	}
371	erase->mtd = mtd;
372	erase->callback = mtdchar_erase_callback;
373	erase->priv = (unsigned long)&waitq;
374
375	/*
376	FIXME: Allow INTERRUPTIBLE. Which means
377	not having the wait_queue head on the stack.
378
379	If the wq_head is on the stack, and we
380	leave because we got interrupted, then the
381	wq_head is no longer there when the
382	callback routine tries to wake us up.
383	*/
384	ret = mtd->erase(mtd, erase);
385	if (!ret) {
386	set_current_state(TASK_UNINTERRUPTIBLE);
387	add_wait_queue(&waitq, &wait);
388	if (erase->state != MTD_ERASE_DONE &&
389	erase->state != MTD_ERASE_FAILED)
390	schedule();
391	remove_wait_queue(&waitq, &wait);
392	set_current_state(TASK_RUNNING);
393
394	ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
395	}
396	kfree(erase);
397	}
398	break;
399	}
400
401	case MEMWRITEOOB:
402	{
403	struct mtd_oob_buf buf;
404	void *databuf;
405	ssize_t retlen;
406
407	if(!(file->f_mode & 2))
408	return -EPERM;
409
410	if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
411	return -EFAULT;
412
413	if (buf.length > 0x4096)
414	return -EINVAL;
415
416	if (!mtd->write_oob)
417	ret = -EOPNOTSUPP;
418	else
419	ret = access_ok(VERIFY_READ, buf.ptr,
420	buf.length) ? 0 : EFAULT;
421
422	if (ret)
423	return ret;
424
425	databuf = kmalloc(buf.length, GFP_KERNEL);
426	if (!databuf)
427	return -ENOMEM;
428
429	if (copy_from_user(databuf, buf.ptr, buf.length)) {
430	kfree(databuf);
431	return -EFAULT;
432	}
433
434	ret = (mtd->write_oob)(mtd, buf.start, buf.length, &retlen, databuf);
435
436	if (copy_to_user(argp + sizeof(uint32_t), &retlen, sizeof(uint32_t)))
437	ret = -EFAULT;
438
439	kfree(databuf);
440	break;
441
442	}
443
444	case MEMREADOOB:
445	{
446	struct mtd_oob_buf buf;
447	void *databuf;
448	ssize_t retlen;
449
450	if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
451	return -EFAULT;
452
453	if (buf.length > 0x4096)
454	return -EINVAL;
455
456	if (!mtd->read_oob)
457	ret = -EOPNOTSUPP;
458	else
459	ret = access_ok(VERIFY_WRITE, buf.ptr,
460	buf.length) ? 0 : -EFAULT;
461
462	if (ret)
463	return ret;
464
465	databuf = kmalloc(buf.length, GFP_KERNEL);
466	if (!databuf)
467	return -ENOMEM;
468
469	ret = (mtd->read_oob)(mtd, buf.start, buf.length, &retlen, databuf);
470
471	if (put_user(retlen, (uint32_t __user *)argp))
472	ret = -EFAULT;
473	else if (retlen && copy_to_user(buf.ptr, databuf, retlen))
474	ret = -EFAULT;
475
476	kfree(databuf);
477	break;
478	}
479
480	case MEMLOCK:
481	{
482	struct erase_info_user info;
483
484	if (copy_from_user(&info, argp, sizeof(info)))
485	return -EFAULT;
486
487	if (!mtd->lock)
488	ret = -EOPNOTSUPP;
489	else
490	ret = mtd->lock(mtd, info.start, info.length);
491	break;
492	}
493
494	case MEMUNLOCK:
495	{
496	struct erase_info_user info;
497
498	if (copy_from_user(&info, argp, sizeof(info)))
499	return -EFAULT;
500
501	if (!mtd->unlock)
502	ret = -EOPNOTSUPP;
503	else
504	ret = mtd->unlock(mtd, info.start, info.length);
505	break;
506	}
507
508	case MEMSETOOBSEL:
509	{
510	if (copy_from_user(&mtd->oobinfo, argp, sizeof(struct nand_oobinfo)))
511	return -EFAULT;
512	break;
513	}
514
515	case MEMGETOOBSEL:
516	{
517	if (copy_to_user(argp, &(mtd->oobinfo), sizeof(struct nand_oobinfo)))
518	return -EFAULT;
519	break;
520	}
521
522	case MEMGETBADBLOCK:
523	{
524	loff_t offs;
525
526	if (copy_from_user(&offs, argp, sizeof(loff_t)))
527	return -EFAULT;
528	if (!mtd->block_isbad)
529	ret = -EOPNOTSUPP;
530	else
531	return mtd->block_isbad(mtd, offs);
532	break;
533	}
534
535	case MEMSETBADBLOCK:
536	{
537	loff_t offs;
538
539	if (copy_from_user(&offs, argp, sizeof(loff_t)))
540	return -EFAULT;
541	if (!mtd->block_markbad)
542	ret = -EOPNOTSUPP;
543	else
544	return mtd->block_markbad(mtd, offs);
545	break;
546	}
547
31f4233b NP	548	#ifdef CONFIG_MTD_OTP
	549	case OTPSELECT:
	550	{
	551	int mode;
	552	if (copy_from_user(&mode, argp, sizeof(int)))
	553	return -EFAULT;
045e9a5d	554	SET_MTD_MODE(file, 0);
31f4233b NP	555	switch (mode) {
	556	case MTD_OTP_FACTORY:
	557	if (!mtd->read_fact_prot_reg)
	558	ret = -EOPNOTSUPP;
	559	else
045e9a5d	560	SET_MTD_MODE(file, MTD_MODE_OTP_FACT);
31f4233b NP	561	break;
	562	case MTD_OTP_USER:
	563	if (!mtd->read_fact_prot_reg)
	564	ret = -EOPNOTSUPP;
	565	else
045e9a5d	566	SET_MTD_MODE(file, MTD_MODE_OTP_USER);
31f4233b NP	567	break;
	568	default:
	569	ret = -EINVAL;
	570	case MTD_OTP_OFF:
	571	break;
	572	}
81dba488	573	file->f_pos = 0;
31f4233b NP	574	break;
	575	}
	576
	577	case OTPGETREGIONCOUNT:
	578	case OTPGETREGIONINFO:
	579	{
	580	struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
	581	if (!buf)
	582	return -ENOMEM;
	583	ret = -EOPNOTSUPP;
045e9a5d	584	switch (MTD_MODE(file)) {
31f4233b NP	585	case MTD_MODE_OTP_FACT:
	586	if (mtd->get_fact_prot_info)
	587	ret = mtd->get_fact_prot_info(mtd, buf, 4096);
	588	break;
	589	case MTD_MODE_OTP_USER:
	590	if (mtd->get_user_prot_info)
	591	ret = mtd->get_user_prot_info(mtd, buf, 4096);
	592	break;
	593	}
	594	if (ret >= 0) {
	595	if (cmd == OTPGETREGIONCOUNT) {
	596	int nbr = ret / sizeof(struct otp_info);
	597	ret = copy_to_user(argp, &nbr, sizeof(int));
	598	} else
	599	ret = copy_to_user(argp, buf, ret);
	600	if (ret)
	601	ret = -EFAULT;
	602	}
	603	kfree(buf);
	604	break;
	605	}
	606
	607	case OTPLOCK:
	608	{
	609	struct otp_info info;
	610
045e9a5d	611	if (MTD_MODE(file) != MTD_MODE_OTP_USER)
31f4233b NP	612	return -EINVAL;
	613	if (copy_from_user(&info, argp, sizeof(info)))
	614	return -EFAULT;
	615	if (!mtd->lock_user_prot_reg)
	616	return -EOPNOTSUPP;
	617	ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
	618	break;
	619	}
	620	#endif
	621
1da177e4 LT	622	default:
	623	ret = -ENOTTY;
	624	}
	625
	626	return ret;
	627	} /* memory_ioctl */
	628
	629	static struct file_operations mtd_fops = {
	630	.owner = THIS_MODULE,
	631	.llseek = mtd_lseek,
	632	.read = mtd_read,
	633	.write = mtd_write,
	634	.ioctl = mtd_ioctl,
	635	.open = mtd_open,
	636	.release = mtd_close,
	637	};
	638
	639	static int __init init_mtdchar(void)
	640	{
	641	if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
	642	printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
	643	MTD_CHAR_MAJOR);
	644	return -EAGAIN;
	645	}
	646
9bc7b387 TP	647	mtd_class = class_create(THIS_MODULE, "mtd");
	648
	649	if (IS_ERR(mtd_class)) {
	650	printk(KERN_ERR "Error creating mtd class.\n");
	651	unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
3a7a8824	652	return PTR_ERR(mtd_class);
9bc7b387 TP	653	}
	654
	655	register_mtd_user(&notifier);
1da177e4 LT	656	return 0;
	657	}
	658
	659	static void __exit cleanup_mtdchar(void)
	660	{
9bc7b387 TP	661	unregister_mtd_user(&notifier);
9bc7b387 TP	662	class_destroy(mtd_class);
1da177e4 LT	663	unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
	664	}
	665
	666	module_init(init_mtdchar);
	667	module_exit(cleanup_mtdchar);
	668
	669
	670	MODULE_LICENSE("GPL");
	671	MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
	672	MODULE_DESCRIPTION("Direct character-device access to MTD devices");