/* * $Id: mtdchar.c,v 1.76 2005/11/07 11:14:20 gleixner Exp $ * * Character-device access to raw MTD devices. * */#include <linux/config.h>#include <linux/device.h>#include <linux/fs.h>#include <linux/init.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/slab.h>#include <linux/sched.h>#include <linux/mtd/mtd.h>#include <linux/mtd/compatmac.h>#include <asm/uaccess.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 0x20000static 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");