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