[linux-block.git] / drivers / mtd / mtdchar.c

/*
 * $Id: mtdchar.c,v 1.74 2005/08/04 01:05:48 tpoynor 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 <linux/sched.h>	/* TASK_* */
#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, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
			    NULL, "mtd%d", mtd->index);
	
	class_device_create(mtd_class, NULL,
			    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 */
		break;
	case 1:
		/* SEEK_CUR */
		offset += file->f_pos;
		break;
	case 2:
		/* SEEK_END */
		offset += mtd->size;
		break;
	default:
		return -EINVAL;
	}

	if (offset >= 0 && offset < mtd->size)
		return file->f_pos = offset;

	return -EINVAL;
}


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	/*
8b491d75	2	* $Id: mtdchar.c,v 1.74 2005/08/04 01:05:48 tpoynor 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>
4e57b681	16	#include <linux/sched.h> /* TASK_* */
1da177e4 LT	17	#include <asm/uaccess.h>
1da177e4 LT	18
9bc7b387 TP	19	#include <linux/device.h>
	20
	21	static struct class *mtd_class;
1da177e4 LT	22
	23	static void mtd_notify_add(struct mtd_info* mtd)
	24	{
	25	if (!mtd)
	26	return;
	27
53f46542	28	class_device_create(mtd_class, NULL, MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
9bc7b387 TP	29	NULL, "mtd%d", mtd->index);
9bc7b387 TP	30
53f46542	31	class_device_create(mtd_class, NULL,
9bc7b387 TP	32	MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
9bc7b387 TP	33	NULL, "mtd%dro", mtd->index);
1da177e4 LT	34	}
	35
	36	static void mtd_notify_remove(struct mtd_info* mtd)
	37	{
	38	if (!mtd)
	39	return;
9bc7b387 TP	40
	41	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2));
	42	class_device_destroy(mtd_class, MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1));
1da177e4 LT	43	}
	44
	45	static struct mtd_notifier notifier = {
	46	.add = mtd_notify_add,
	47	.remove = mtd_notify_remove,
	48	};
	49
045e9a5d NP	50	/*
	51	* We use file->private_data to store a pointer to the MTDdevice.
	52	* Since alighment is at least 32 bits, we have 2 bits free for OTP
	53	* modes as well.
	54	*/
	55
	56	#define TO_MTD(file) (struct mtd_info *)((long)((file)->private_data) & ~3L)
31f4233b	57
045e9a5d NP	58	#define MTD_MODE_OTP_FACT 1
	59	#define MTD_MODE_OTP_USER 2
	60	#define MTD_MODE(file) ((long)((file)->private_data) & 3)
	61
	62	#define SET_MTD_MODE(file, mode) \
	63	do { long __p = (long)((file)->private_data); \
	64	(file)->private_data = (void *)((__p & ~3L) \| mode); } while (0)
31f4233b	65
1da177e4 LT	66	static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
1da177e4 LT	67	{
045e9a5d	68	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	69
	70	switch (orig) {
	71	case 0:
	72	/* SEEK_SET */
1da177e4 LT	73	break;
	74	case 1:
	75	/* SEEK_CUR */
8b491d75	76	offset += file->f_pos;
1da177e4 LT	77	break;
	78	case 2:
	79	/* SEEK_END */
8b491d75	80	offset += mtd->size;
1da177e4 LT	81	break;
	82	default:
	83	return -EINVAL;
	84	}
	85
8b491d75 TP	86	if (offset >= 0 && offset < mtd->size)
8b491d75 TP	87	return file->f_pos = offset;
1da177e4	88
8b491d75	89	return -EINVAL;
1da177e4 LT	90	}
	91
	92
	93
	94	static int mtd_open(struct inode inode, struct file file)
	95	{
	96	int minor = iminor(inode);
	97	int devnum = minor >> 1;
	98	struct mtd_info *mtd;
	99
	100	DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
	101
	102	if (devnum >= MAX_MTD_DEVICES)
	103	return -ENODEV;
	104
	105	/* You can't open the RO devices RW */
	106	if ((file->f_mode & 2) && (minor & 1))
	107	return -EACCES;
	108
	109	mtd = get_mtd_device(NULL, devnum);
	110
	111	if (!mtd)
	112	return -ENODEV;
	113
	114	if (MTD_ABSENT == mtd->type) {
	115	put_mtd_device(mtd);
	116	return -ENODEV;
	117	}
	118
	119	file->private_data = mtd;
	120
	121	/* You can't open it RW if it's not a writeable device */
	122	if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
	123	put_mtd_device(mtd);
	124	return -EACCES;
	125	}
	126
	127	return 0;
	128	} /* mtd_open */
	129
	130	/====================================================================/
	131
	132	static int mtd_close(struct inode inode, struct file file)
	133	{
	134	struct mtd_info *mtd;
	135
	136	DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
	137
045e9a5d	138	mtd = TO_MTD(file);
1da177e4 LT	139
	140	if (mtd->sync)
	141	mtd->sync(mtd);
	142
	143	put_mtd_device(mtd);
	144
	145	return 0;
	146	} /* mtd_close */
	147
	148	/* FIXME: This _really_ needs to die. In 2.5, we should lock the
	149	userspace buffer down and use it directly with readv/writev.
	150	*/
	151	#define MAX_KMALLOC_SIZE 0x20000
	152
	153	static ssize_t mtd_read(struct file file, char __user buf, size_t count,loff_t *ppos)
	154	{
045e9a5d	155	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	156	size_t retlen=0;
	157	size_t total_retlen=0;
	158	int ret=0;
	159	int len;
	160	char *kbuf;
	161
	162	DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
	163
	164	if (*ppos + count > mtd->size)
	165	count = mtd->size - *ppos;
	166
	167	if (!count)
	168	return 0;
	169
	170	/* FIXME: Use kiovec in 2.5 to lock down the user's buffers
	171	and pass them directly to the MTD functions */
	172	while (count) {
	173	if (count > MAX_KMALLOC_SIZE)
	174	len = MAX_KMALLOC_SIZE;
	175	else
	176	len = count;
	177
	178	kbuf=kmalloc(len,GFP_KERNEL);
	179	if (!kbuf)
	180	return -ENOMEM;
	181
045e9a5d	182	switch (MTD_MODE(file)) {
31f4233b NP	183	case MTD_MODE_OTP_FACT:
	184	ret = mtd->read_fact_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	185	break;
	186	case MTD_MODE_OTP_USER:
	187	ret = mtd->read_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	188	break;
	189	default:
	190	ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
	191	}
1da177e4 LT	192	/* Nand returns -EBADMSG on ecc errors, but it returns
	193	* the data. For our userspace tools it is important
	194	* to dump areas with ecc errors !
	195	* Userspace software which accesses NAND this way
	196	* must be aware of the fact that it deals with NAND
	197	*/
	198	if (!ret \|\| (ret == -EBADMSG)) {
	199	*ppos += retlen;
	200	if (copy_to_user(buf, kbuf, retlen)) {
	201	kfree(kbuf);
	202	return -EFAULT;
	203	}
	204	else
	205	total_retlen += retlen;
	206
	207	count -= retlen;
	208	buf += retlen;
31f4233b NP	209	if (retlen == 0)
31f4233b NP	210	count = 0;
1da177e4 LT	211	}
	212	else {
	213	kfree(kbuf);
	214	return ret;
	215	}
	216
	217	kfree(kbuf);
	218	}
	219
	220	return total_retlen;
	221	} /* mtd_read */
	222
	223	static ssize_t mtd_write(struct file file, const char __user buf, size_t count,loff_t *ppos)
	224	{
045e9a5d	225	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	226	char *kbuf;
	227	size_t retlen;
	228	size_t total_retlen=0;
	229	int ret=0;
	230	int len;
	231
	232	DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
	233
	234	if (*ppos == mtd->size)
	235	return -ENOSPC;
	236
	237	if (*ppos + count > mtd->size)
	238	count = mtd->size - *ppos;
	239
	240	if (!count)
	241	return 0;
	242
	243	while (count) {
	244	if (count > MAX_KMALLOC_SIZE)
	245	len = MAX_KMALLOC_SIZE;
	246	else
	247	len = count;
	248
	249	kbuf=kmalloc(len,GFP_KERNEL);
	250	if (!kbuf) {
	251	printk("kmalloc is null\n");
	252	return -ENOMEM;
	253	}
	254
	255	if (copy_from_user(kbuf, buf, len)) {
	256	kfree(kbuf);
	257	return -EFAULT;
	258	}
	259
045e9a5d	260	switch (MTD_MODE(file)) {
31f4233b NP	261	case MTD_MODE_OTP_FACT:
	262	ret = -EROFS;
	263	break;
	264	case MTD_MODE_OTP_USER:
	265	if (!mtd->write_user_prot_reg) {
	266	ret = -EOPNOTSUPP;
	267	break;
	268	}
	269	ret = mtd->write_user_prot_reg(mtd, *ppos, len, &retlen, kbuf);
	270	break;
	271	default:
	272	ret = ((mtd->write))(mtd, ppos, len, &retlen, kbuf);
	273	}
1da177e4 LT	274	if (!ret) {
	275	*ppos += retlen;
	276	total_retlen += retlen;
	277	count -= retlen;
	278	buf += retlen;
	279	}
	280	else {
	281	kfree(kbuf);
	282	return ret;
	283	}
	284
	285	kfree(kbuf);
	286	}
	287
	288	return total_retlen;
	289	} /* mtd_write */
	290
	291	/*======================================================================
	292
	293	IOCTL calls for getting device parameters.
	294
	295	======================================================================*/
	296	static void mtdchar_erase_callback (struct erase_info *instr)
	297	{
	298	wake_up((wait_queue_head_t *)instr->priv);
	299	}
	300
	301	static int mtd_ioctl(struct inode inode, struct file file,
	302	u_int cmd, u_long arg)
	303	{
045e9a5d	304	struct mtd_info *mtd = TO_MTD(file);
1da177e4 LT	305	void __user argp = (void __user )arg;
	306	int ret = 0;
	307	u_long size;
	308
	309	DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
	310
	311	size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
	312	if (cmd & IOC_IN) {
	313	if (!access_ok(VERIFY_READ, argp, size))
	314	return -EFAULT;
	315	}
	316	if (cmd & IOC_OUT) {
	317	if (!access_ok(VERIFY_WRITE, argp, size))
	318	return -EFAULT;
	319	}
	320
	321	switch (cmd) {
	322	case MEMGETREGIONCOUNT:
	323	if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
	324	return -EFAULT;
	325	break;
	326
	327	case MEMGETREGIONINFO:
	328	{
	329	struct region_info_user ur;
	330
	331	if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
	332	return -EFAULT;
	333
	334	if (ur.regionindex >= mtd->numeraseregions)
	335	return -EINVAL;
	336	if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
	337	sizeof(struct mtd_erase_region_info)))
	338	return -EFAULT;
	339	break;
	340	}
	341
	342	case MEMGETINFO:
	343	if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
	344	return -EFAULT;
	345	break;
	346
	347	case MEMERASE:
	348	{
	349	struct erase_info *erase;
	350
	351	if(!(file->f_mode & 2))
	352	return -EPERM;
	353
	354	erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
	355	if (!erase)
	356	ret = -ENOMEM;
	357	else {
	358	wait_queue_head_t waitq;
	359	DECLARE_WAITQUEUE(wait, current);
	360
	361	init_waitqueue_head(&waitq);
	362
	363	memset (erase,0,sizeof(struct erase_info));
	364	if (copy_from_user(&erase->addr, argp,
	365	sizeof(struct erase_info_user))) {
	366	kfree(erase);
	367	return -EFAULT;
	368	}
369	erase->mtd = mtd;
370	erase->callback = mtdchar_erase_callback;
371	erase->priv = (unsigned long)&waitq;
372
373	/*
374	FIXME: Allow INTERRUPTIBLE. Which means
375	not having the wait_queue head on the stack.
376
377	If the wq_head is on the stack, and we
378	leave because we got interrupted, then the
379	wq_head is no longer there when the
380	callback routine tries to wake us up.
381	*/
382	ret = mtd->erase(mtd, erase);
383	if (!ret) {
384	set_current_state(TASK_UNINTERRUPTIBLE);
385	add_wait_queue(&waitq, &wait);
386	if (erase->state != MTD_ERASE_DONE &&
387	erase->state != MTD_ERASE_FAILED)
388	schedule();
389	remove_wait_queue(&waitq, &wait);
390	set_current_state(TASK_RUNNING);
391
392	ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
393	}
394	kfree(erase);
395	}
396	break;
397	}
398
399	case MEMWRITEOOB:
400	{
401	struct mtd_oob_buf buf;
402	void *databuf;
403	ssize_t retlen;
404
405	if(!(file->f_mode & 2))
406	return -EPERM;
407
408	if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
409	return -EFAULT;
410
411	if (buf.length > 0x4096)
412	return -EINVAL;
413
414	if (!mtd->write_oob)
415	ret = -EOPNOTSUPP;
416	else
417	ret = access_ok(VERIFY_READ, buf.ptr,
418	buf.length) ? 0 : EFAULT;
419
420	if (ret)
421	return ret;
422
423	databuf = kmalloc(buf.length, GFP_KERNEL);
424	if (!databuf)
425	return -ENOMEM;
426
427	if (copy_from_user(databuf, buf.ptr, buf.length)) {
428	kfree(databuf);
429	return -EFAULT;
430	}
431
432	ret = (mtd->write_oob)(mtd, buf.start, buf.length, &retlen, databuf);
433
434	if (copy_to_user(argp + sizeof(uint32_t), &retlen, sizeof(uint32_t)))
435	ret = -EFAULT;
436
437	kfree(databuf);
438	break;
439
440	}
441
442	case MEMREADOOB:
443	{
444	struct mtd_oob_buf buf;
445	void *databuf;
446	ssize_t retlen;
447
448	if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
449	return -EFAULT;
450
451	if (buf.length > 0x4096)
452	return -EINVAL;
453
454	if (!mtd->read_oob)
455	ret = -EOPNOTSUPP;
456	else
457	ret = access_ok(VERIFY_WRITE, buf.ptr,
458	buf.length) ? 0 : -EFAULT;
459
460	if (ret)
461	return ret;
462
463	databuf = kmalloc(buf.length, GFP_KERNEL);
464	if (!databuf)
465	return -ENOMEM;
466
467	ret = (mtd->read_oob)(mtd, buf.start, buf.length, &retlen, databuf);
468
469	if (put_user(retlen, (uint32_t __user *)argp))
470	ret = -EFAULT;
471	else if (retlen && copy_to_user(buf.ptr, databuf, retlen))
472	ret = -EFAULT;
473
474	kfree(databuf);
475	break;
476	}
477
478	case MEMLOCK:
479	{
480	struct erase_info_user info;
481
482	if (copy_from_user(&info, argp, sizeof(info)))
483	return -EFAULT;
484
485	if (!mtd->lock)
486	ret = -EOPNOTSUPP;
487	else
488	ret = mtd->lock(mtd, info.start, info.length);
489	break;
490	}
491
492	case MEMUNLOCK:
493	{
494	struct erase_info_user info;
495
496	if (copy_from_user(&info, argp, sizeof(info)))
497	return -EFAULT;
498
499	if (!mtd->unlock)
500	ret = -EOPNOTSUPP;
501	else
502	ret = mtd->unlock(mtd, info.start, info.length);
503	break;
504	}
505
506	case MEMSETOOBSEL:
507	{
508	if (copy_from_user(&mtd->oobinfo, argp, sizeof(struct nand_oobinfo)))
509	return -EFAULT;
510	break;
511	}
512
513	case MEMGETOOBSEL:
514	{
515	if (copy_to_user(argp, &(mtd->oobinfo), sizeof(struct nand_oobinfo)))
516	return -EFAULT;
517	break;
518	}
519
520	case MEMGETBADBLOCK:
521	{
522	loff_t offs;
523
524	if (copy_from_user(&offs, argp, sizeof(loff_t)))
525	return -EFAULT;
526	if (!mtd->block_isbad)
527	ret = -EOPNOTSUPP;
528	else
529	return mtd->block_isbad(mtd, offs);
530	break;
531	}
532
533	case MEMSETBADBLOCK:
534	{
535	loff_t offs;
536
537	if (copy_from_user(&offs, argp, sizeof(loff_t)))
538	return -EFAULT;
539	if (!mtd->block_markbad)
540	ret = -EOPNOTSUPP;
541	else
542	return mtd->block_markbad(mtd, offs);
543	break;
544	}
545
31f4233b NP	546	#ifdef CONFIG_MTD_OTP
	547	case OTPSELECT:
	548	{
	549	int mode;
	550	if (copy_from_user(&mode, argp, sizeof(int)))
	551	return -EFAULT;
045e9a5d	552	SET_MTD_MODE(file, 0);
31f4233b NP	553	switch (mode) {
	554	case MTD_OTP_FACTORY:
	555	if (!mtd->read_fact_prot_reg)
	556	ret = -EOPNOTSUPP;
	557	else
045e9a5d	558	SET_MTD_MODE(file, MTD_MODE_OTP_FACT);
31f4233b NP	559	break;
	560	case MTD_OTP_USER:
	561	if (!mtd->read_fact_prot_reg)
	562	ret = -EOPNOTSUPP;
	563	else
045e9a5d	564	SET_MTD_MODE(file, MTD_MODE_OTP_USER);
31f4233b NP	565	break;
	566	default:
	567	ret = -EINVAL;
	568	case MTD_OTP_OFF:
	569	break;
	570	}
81dba488	571	file->f_pos = 0;
31f4233b NP	572	break;
	573	}
	574
	575	case OTPGETREGIONCOUNT:
	576	case OTPGETREGIONINFO:
	577	{
	578	struct otp_info *buf = kmalloc(4096, GFP_KERNEL);
	579	if (!buf)
	580	return -ENOMEM;
	581	ret = -EOPNOTSUPP;
045e9a5d	582	switch (MTD_MODE(file)) {
31f4233b NP	583	case MTD_MODE_OTP_FACT:
	584	if (mtd->get_fact_prot_info)
	585	ret = mtd->get_fact_prot_info(mtd, buf, 4096);
	586	break;
	587	case MTD_MODE_OTP_USER:
	588	if (mtd->get_user_prot_info)
	589	ret = mtd->get_user_prot_info(mtd, buf, 4096);
	590	break;
	591	}
	592	if (ret >= 0) {
	593	if (cmd == OTPGETREGIONCOUNT) {
	594	int nbr = ret / sizeof(struct otp_info);
	595	ret = copy_to_user(argp, &nbr, sizeof(int));
	596	} else
	597	ret = copy_to_user(argp, buf, ret);
	598	if (ret)
	599	ret = -EFAULT;
	600	}
	601	kfree(buf);
	602	break;
	603	}
	604
	605	case OTPLOCK:
	606	{
	607	struct otp_info info;
	608
045e9a5d	609	if (MTD_MODE(file) != MTD_MODE_OTP_USER)
31f4233b NP	610	return -EINVAL;
	611	if (copy_from_user(&info, argp, sizeof(info)))
	612	return -EFAULT;
	613	if (!mtd->lock_user_prot_reg)
	614	return -EOPNOTSUPP;
	615	ret = mtd->lock_user_prot_reg(mtd, info.start, info.length);
	616	break;
	617	}
	618	#endif
	619
1da177e4 LT	620	default:
	621	ret = -ENOTTY;
	622	}
	623
	624	return ret;
	625	} /* memory_ioctl */
	626
	627	static struct file_operations mtd_fops = {
	628	.owner = THIS_MODULE,
	629	.llseek = mtd_lseek,
	630	.read = mtd_read,
	631	.write = mtd_write,
	632	.ioctl = mtd_ioctl,
	633	.open = mtd_open,
	634	.release = mtd_close,
	635	};
	636
	637	static int __init init_mtdchar(void)
	638	{
	639	if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
	640	printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
	641	MTD_CHAR_MAJOR);
	642	return -EAGAIN;
	643	}
	644
9bc7b387 TP	645	mtd_class = class_create(THIS_MODULE, "mtd");
	646
	647	if (IS_ERR(mtd_class)) {
	648	printk(KERN_ERR "Error creating mtd class.\n");
	649	unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
3a7a8824	650	return PTR_ERR(mtd_class);
9bc7b387 TP	651	}
	652
	653	register_mtd_user(&notifier);
1da177e4 LT	654	return 0;
	655	}
	656
	657	static void __exit cleanup_mtdchar(void)
	658	{
9bc7b387 TP	659	unregister_mtd_user(&notifier);
9bc7b387 TP	660	class_destroy(mtd_class);
1da177e4 LT	661	unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
	662	}
	663
	664	module_init(init_mtdchar);
	665	module_exit(cleanup_mtdchar);
	666
	667
	668	MODULE_LICENSE("GPL");
	669	MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
	670	MODULE_DESCRIPTION("Direct character-device access to MTD devices");