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

/*
 * $Id: mtdcore.c,v 1.47 2005/11/07 11:14:20 gleixner Exp $
 *
 * Core registration and callback routines for MTD
 * drivers and users.
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/timer.h>
#include <linux/major.h>
#include <linux/fs.h>
#include <linux/err.h>
#include <linux/ioctl.h>
#include <linux/init.h>
#include <linux/mtd/compatmac.h>
#include <linux/proc_fs.h>

#include <linux/mtd/mtd.h>

#include "mtdcore.h"

/* These are exported solely for the purpose of mtd_blkdevs.c. You
   should not use them for _anything_ else */
DEFINE_MUTEX(mtd_table_mutex);
struct mtd_info *mtd_table[MAX_MTD_DEVICES];

EXPORT_SYMBOL_GPL(mtd_table_mutex);
EXPORT_SYMBOL_GPL(mtd_table);

static LIST_HEAD(mtd_notifiers);

/**
 *	add_mtd_device - register an MTD device
 *	@mtd: pointer to new MTD device info structure
 *
 *	Add a device to the list of MTD devices present in the system, and
 *	notify each currently active MTD 'user' of its arrival. Returns
 *	zero on success or 1 on failure, which currently will only happen
 *	if the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16)
 */

int add_mtd_device(struct mtd_info *mtd)
{
	int i;

	BUG_ON(mtd->writesize == 0);
	mutex_lock(&mtd_table_mutex);

	for (i=0; i < MAX_MTD_DEVICES; i++)
		if (!mtd_table[i]) {
			struct list_head *this;

			mtd_table[i] = mtd;
			mtd->index = i;
			mtd->usecount = 0;

			/* Some chips always power up locked. Unlock them now */
			if ((mtd->flags & MTD_WRITEABLE)
			    && (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) {
				if (mtd->unlock(mtd, 0, mtd->size))
					printk(KERN_WARNING
					       "%s: unlock failed, "
					       "writes may not work\n",
					       mtd->name);
			}

			DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name);
			/* No need to get a refcount on the module containing
			   the notifier, since we hold the mtd_table_mutex */
			list_for_each(this, &mtd_notifiers) {
				struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
				not->add(mtd);
			}

			mutex_unlock(&mtd_table_mutex);
			/* We _know_ we aren't being removed, because
			   our caller is still holding us here. So none
			   of this try_ nonsense, and no bitching about it
			   either. :) */
			__module_get(THIS_MODULE);
			return 0;
		}

	mutex_unlock(&mtd_table_mutex);
	return 1;
}

/**
 *	del_mtd_device - unregister an MTD device
 *	@mtd: pointer to MTD device info structure
 *
 *	Remove a device from the list of MTD devices present in the system,
 *	and notify each currently active MTD 'user' of its departure.
 *	Returns zero on success or 1 on failure, which currently will happen
 *	if the requested device does not appear to be present in the list.
 */

int del_mtd_device (struct mtd_info *mtd)
{
	int ret;

	mutex_lock(&mtd_table_mutex);

	if (mtd_table[mtd->index] != mtd) {
		ret = -ENODEV;
	} else if (mtd->usecount) {
		printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
		       mtd->index, mtd->name, mtd->usecount);
		ret = -EBUSY;
	} else {
		struct list_head *this;

		/* No need to get a refcount on the module containing
		   the notifier, since we hold the mtd_table_mutex */
		list_for_each(this, &mtd_notifiers) {
			struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
			not->remove(mtd);
		}

		mtd_table[mtd->index] = NULL;

		module_put(THIS_MODULE);
		ret = 0;
	}

	mutex_unlock(&mtd_table_mutex);
	return ret;
}

/**
 *	register_mtd_user - register a 'user' of MTD devices.
 *	@new: pointer to notifier info structure
 *
 *	Registers a pair of callbacks function to be called upon addition
 *	or removal of MTD devices. Causes the 'add' callback to be immediately
 *	invoked for each MTD device currently present in the system.
 */

void register_mtd_user (struct mtd_notifier *new)
{
	int i;

	mutex_lock(&mtd_table_mutex);

	list_add(&new->list, &mtd_notifiers);

 	__module_get(THIS_MODULE);

	for (i=0; i< MAX_MTD_DEVICES; i++)
		if (mtd_table[i])
			new->add(mtd_table[i]);

	mutex_unlock(&mtd_table_mutex);
}

/**
 *	unregister_mtd_user - unregister a 'user' of MTD devices.
 *	@old: pointer to notifier info structure
 *
 *	Removes a callback function pair from the list of 'users' to be
 *	notified upon addition or removal of MTD devices. Causes the
 *	'remove' callback to be immediately invoked for each MTD device
 *	currently present in the system.
 */

int unregister_mtd_user (struct mtd_notifier *old)
{
	int i;

	mutex_lock(&mtd_table_mutex);

	module_put(THIS_MODULE);

	for (i=0; i< MAX_MTD_DEVICES; i++)
		if (mtd_table[i])
			old->remove(mtd_table[i]);

	list_del(&old->list);
	mutex_unlock(&mtd_table_mutex);
	return 0;
}


/**
 *	get_mtd_device - obtain a validated handle for an MTD device
 *	@mtd: last known address of the required MTD device
 *	@num: internal device number of the required MTD device
 *
 *	Given a number and NULL address, return the num'th entry in the device
 *	table, if any.	Given an address and num == -1, search the device table
 *	for a device with that address and return if it's still present. Given
 *	both, return the num'th driver only if its address matches. Return
 *	error code if not.
 */

struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
{
	struct mtd_info *ret = NULL;
	int i, err = -ENODEV;

	mutex_lock(&mtd_table_mutex);

	if (num == -1) {
		for (i=0; i< MAX_MTD_DEVICES; i++)
			if (mtd_table[i] == mtd)
				ret = mtd_table[i];
	} else if (num < MAX_MTD_DEVICES) {
		ret = mtd_table[num];
		if (mtd && mtd != ret)
			ret = NULL;
	}

	if (!ret)
		goto out_unlock;

	if (!try_module_get(ret->owner))
		goto out_unlock;

	if (ret->get_device) {
		err = ret->get_device(ret);
		if (err)
			goto out_put;
	}

	ret->usecount++;
	mutex_unlock(&mtd_table_mutex);
	return ret;

out_put:
	module_put(ret->owner);
out_unlock:
	mutex_unlock(&mtd_table_mutex);
	return ERR_PTR(err);
}

/**
 *	get_mtd_device_nm - obtain a validated handle for an MTD device by
 *	device name
 *	@name: MTD device name to open
 *
 * 	This function returns MTD device description structure in case of
 * 	success and an error code in case of failure.
 */

struct mtd_info *get_mtd_device_nm(const char *name)
{
	int i, err = -ENODEV;
	struct mtd_info *mtd = NULL;

	mutex_lock(&mtd_table_mutex);

	for (i = 0; i < MAX_MTD_DEVICES; i++) {
		if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) {
			mtd = mtd_table[i];
			break;
		}
	}

	if (!mtd)
		goto out_unlock;

	if (!try_module_get(mtd->owner))
		goto out_unlock;

	if (mtd->get_device) {
		err = mtd->get_device(mtd);
		if (err)
			goto out_put;
	}

	mtd->usecount++;
	mutex_unlock(&mtd_table_mutex);
	return mtd;

out_put:
	module_put(mtd->owner);
out_unlock:
	mutex_unlock(&mtd_table_mutex);
	return ERR_PTR(err);
}

void put_mtd_device(struct mtd_info *mtd)
{
	int c;

	mutex_lock(&mtd_table_mutex);
	c = --mtd->usecount;
	if (mtd->put_device)
		mtd->put_device(mtd);
	mutex_unlock(&mtd_table_mutex);
	BUG_ON(c < 0);

	module_put(mtd->owner);
}

/* default_mtd_writev - default mtd writev method for MTD devices that
 *			don't implement their own
 */

int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
		       unsigned long count, loff_t to, size_t *retlen)
{
	unsigned long i;
	size_t totlen = 0, thislen;
	int ret = 0;

	if(!mtd->write) {
		ret = -EROFS;
	} else {
		for (i=0; i<count; i++) {
			if (!vecs[i].iov_len)
				continue;
			ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base);
			totlen += thislen;
			if (ret || thislen != vecs[i].iov_len)
				break;
			to += vecs[i].iov_len;
		}
	}
	if (retlen)
		*retlen = totlen;
	return ret;
}

EXPORT_SYMBOL_GPL(add_mtd_device);
EXPORT_SYMBOL_GPL(del_mtd_device);
EXPORT_SYMBOL_GPL(get_mtd_device);
EXPORT_SYMBOL_GPL(get_mtd_device_nm);
EXPORT_SYMBOL_GPL(put_mtd_device);
EXPORT_SYMBOL_GPL(register_mtd_user);
EXPORT_SYMBOL_GPL(unregister_mtd_user);
EXPORT_SYMBOL_GPL(default_mtd_writev);

#ifdef CONFIG_PROC_FS

/*====================================================================*/
/* Support for /proc/mtd */

static struct proc_dir_entry *proc_mtd;

static inline int mtd_proc_info (char *buf, int i)
{
	struct mtd_info *this = mtd_table[i];

	if (!this)
		return 0;

	return sprintf(buf, "mtd%d: %8.8x %8.8x \"%s\"\n", i, this->size,
		       this->erasesize, this->name);
}

static int mtd_read_proc (char *page, char **start, off_t off, int count,
			  int *eof, void *data_unused)
{
	int len, l, i;
        off_t   begin = 0;

	mutex_lock(&mtd_table_mutex);

	len = sprintf(page, "dev:    size   erasesize  name\n");
        for (i=0; i< MAX_MTD_DEVICES; i++) {

                l = mtd_proc_info(page + len, i);
                len += l;
                if (len+begin > off+count)
                        goto done;
                if (len+begin < off) {
                        begin += len;
                        len = 0;
                }
        }

        *eof = 1;

done:
	mutex_unlock(&mtd_table_mutex);
        if (off >= len+begin)
                return 0;
        *start = page + (off-begin);
        return ((count < begin+len-off) ? count : begin+len-off);
}

/*====================================================================*/
/* Init code */

static int __init init_mtd(void)
{
	if ((proc_mtd = create_proc_entry( "mtd", 0, NULL )))
		proc_mtd->read_proc = mtd_read_proc;
	return 0;
}

static void __exit cleanup_mtd(void)
{
        if (proc_mtd)
		remove_proc_entry( "mtd", NULL);
}

module_init(init_mtd);
module_exit(cleanup_mtd);

#endif /* CONFIG_PROC_FS */


MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
MODULE_DESCRIPTION("Core MTD registration and access routines");
Commit	Line	Data
1da177e4	1	/*
97894cda	2	* $Id: mtdcore.c,v 1.47 2005/11/07 11:14:20 gleixner Exp $
1da177e4 LT	3	*
	4	* Core registration and callback routines for MTD
	5	* drivers and users.
	6	*
	7	*/
	8
1da177e4 LT	9	#include <linux/module.h>
1da177e4 LT	10	#include <linux/kernel.h>
1da177e4 LT	11	#include <linux/ptrace.h>
	12	#include <linux/slab.h>
	13	#include <linux/string.h>
	14	#include <linux/timer.h>
	15	#include <linux/major.h>
	16	#include <linux/fs.h>
7799308f	17	#include <linux/err.h>
1da177e4 LT	18	#include <linux/ioctl.h>
	19	#include <linux/init.h>
	20	#include <linux/mtd/compatmac.h>
1da177e4	21	#include <linux/proc_fs.h>
1da177e4 LT	22
	23	#include <linux/mtd/mtd.h>
	24
356d70f1 BD	25	#include "mtdcore.h"
356d70f1 BD	26
97894cda	27	/* These are exported solely for the purpose of mtd_blkdevs.c. You
1da177e4	28	should not use them for _anything_ else */
48b19268	29	DEFINE_MUTEX(mtd_table_mutex);
1da177e4 LT	30	struct mtd_info *mtd_table[MAX_MTD_DEVICES];
	31
	32	EXPORT_SYMBOL_GPL(mtd_table_mutex);
	33	EXPORT_SYMBOL_GPL(mtd_table);
	34
	35	static LIST_HEAD(mtd_notifiers);
	36
	37	/**
	38	* add_mtd_device - register an MTD device
	39	* @mtd: pointer to new MTD device info structure
	40	*
	41	* Add a device to the list of MTD devices present in the system, and
	42	* notify each currently active MTD 'user' of its arrival. Returns
	43	* zero on success or 1 on failure, which currently will only happen
	44	* if the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16)
	45	*/
	46
	47	int add_mtd_device(struct mtd_info *mtd)
	48	{
	49	int i;
	50
783ed81f	51	BUG_ON(mtd->writesize == 0);
48b19268	52	mutex_lock(&mtd_table_mutex);
1da177e4 LT	53
	54	for (i=0; i < MAX_MTD_DEVICES; i++)
	55	if (!mtd_table[i]) {
	56	struct list_head *this;
	57
	58	mtd_table[i] = mtd;
	59	mtd->index = i;
	60	mtd->usecount = 0;
	61
187ef152 HS	62	/* Some chips always power up locked. Unlock them now */
187ef152 HS	63	if ((mtd->flags & MTD_WRITEABLE)
e619a75f	64	&& (mtd->flags & MTD_POWERUP_LOCK) && mtd->unlock) {
187ef152 HS	65	if (mtd->unlock(mtd, 0, mtd->size))
	66	printk(KERN_WARNING
	67	"%s: unlock failed, "
	68	"writes may not work\n",
	69	mtd->name);
	70	}
	71
1da177e4 LT	72	DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name);
	73	/* No need to get a refcount on the module containing
	74	the notifier, since we hold the mtd_table_mutex */
	75	list_for_each(this, &mtd_notifiers) {
	76	struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
	77	not->add(mtd);
	78	}
97894cda	79
48b19268	80	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	81	/* We _know_ we aren't being removed, because
	82	our caller is still holding us here. So none
	83	of this try_ nonsense, and no bitching about it
	84	either. :) */
	85	__module_get(THIS_MODULE);
	86	return 0;
	87	}
97894cda	88
48b19268	89	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	90	return 1;
	91	}
	92
	93	/**
	94	* del_mtd_device - unregister an MTD device
	95	* @mtd: pointer to MTD device info structure
	96	*
	97	* Remove a device from the list of MTD devices present in the system,
	98	* and notify each currently active MTD 'user' of its departure.
	99	* Returns zero on success or 1 on failure, which currently will happen
	100	* if the requested device does not appear to be present in the list.
	101	*/
	102
	103	int del_mtd_device (struct mtd_info *mtd)
	104	{
	105	int ret;
97894cda	106
48b19268	107	mutex_lock(&mtd_table_mutex);
1da177e4 LT	108
	109	if (mtd_table[mtd->index] != mtd) {
	110	ret = -ENODEV;
	111	} else if (mtd->usecount) {
97894cda	112	printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
1da177e4 LT	113	mtd->index, mtd->name, mtd->usecount);
	114	ret = -EBUSY;
	115	} else {
	116	struct list_head *this;
	117
	118	/* No need to get a refcount on the module containing
	119	the notifier, since we hold the mtd_table_mutex */
	120	list_for_each(this, &mtd_notifiers) {
	121	struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
	122	not->remove(mtd);
	123	}
	124
	125	mtd_table[mtd->index] = NULL;
	126
	127	module_put(THIS_MODULE);
	128	ret = 0;
	129	}
	130
48b19268	131	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	132	return ret;
	133	}
	134
	135	/**
	136	* register_mtd_user - register a 'user' of MTD devices.
	137	* @new: pointer to notifier info structure
	138	*
	139	* Registers a pair of callbacks function to be called upon addition
	140	* or removal of MTD devices. Causes the 'add' callback to be immediately
	141	* invoked for each MTD device currently present in the system.
	142	*/
	143
	144	void register_mtd_user (struct mtd_notifier *new)
	145	{
	146	int i;
	147
48b19268	148	mutex_lock(&mtd_table_mutex);
1da177e4 LT	149
	150	list_add(&new->list, &mtd_notifiers);
	151
	152	__module_get(THIS_MODULE);
97894cda	153
1da177e4 LT	154	for (i=0; i< MAX_MTD_DEVICES; i++)
	155	if (mtd_table[i])
	156	new->add(mtd_table[i]);
	157
48b19268	158	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	159	}
	160
	161	/**
49450795 AB	162	* unregister_mtd_user - unregister a 'user' of MTD devices.
49450795 AB	163	* @old: pointer to notifier info structure
1da177e4 LT	164	*
	165	* Removes a callback function pair from the list of 'users' to be
	166	* notified upon addition or removal of MTD devices. Causes the
	167	* 'remove' callback to be immediately invoked for each MTD device
	168	* currently present in the system.
	169	*/
	170
	171	int unregister_mtd_user (struct mtd_notifier *old)
	172	{
	173	int i;
	174
48b19268	175	mutex_lock(&mtd_table_mutex);
1da177e4 LT	176
	177	module_put(THIS_MODULE);
	178
	179	for (i=0; i< MAX_MTD_DEVICES; i++)
	180	if (mtd_table[i])
	181	old->remove(mtd_table[i]);
97894cda	182
1da177e4	183	list_del(&old->list);
48b19268	184	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	185	return 0;
	186	}
	187
	188
	189	/**
	190	* get_mtd_device - obtain a validated handle for an MTD device
	191	* @mtd: last known address of the required MTD device
	192	* @num: internal device number of the required MTD device
	193	*
	194	* Given a number and NULL address, return the num'th entry in the device
	195	* table, if any. Given an address and num == -1, search the device table
	196	* for a device with that address and return if it's still present. Given
9c74034f AB	197	* both, return the num'th driver only if its address matches. Return
9c74034f AB	198	* error code if not.
1da177e4	199	*/
97894cda	200
1da177e4 LT	201	struct mtd_info get_mtd_device(struct mtd_info mtd, int num)
	202	{
	203	struct mtd_info *ret = NULL;
9c74034f	204	int i, err = -ENODEV;
1da177e4	205
48b19268	206	mutex_lock(&mtd_table_mutex);
1da177e4 LT	207
	208	if (num == -1) {
	209	for (i=0; i< MAX_MTD_DEVICES; i++)
	210	if (mtd_table[i] == mtd)
	211	ret = mtd_table[i];
	212	} else if (num < MAX_MTD_DEVICES) {
	213	ret = mtd_table[num];
	214	if (mtd && mtd != ret)
	215	ret = NULL;
	216	}
	217
9fe912ce AB	218	if (!ret)
	219	goto out_unlock;
	220
9c74034f	221	if (!try_module_get(ret->owner))
9fe912ce	222	goto out_unlock;
9fe912ce	223
9c74034f AB	224	if (ret->get_device) {
	225	err = ret->get_device(ret);
	226	if (err)
	227	goto out_put;
9fe912ce	228	}
1da177e4	229
9fe912ce	230	ret->usecount++;
9c74034f AB	231	mutex_unlock(&mtd_table_mutex);
9c74034f AB	232	return ret;
1da177e4	233
9c74034f AB	234	out_put:
9c74034f AB	235	module_put(ret->owner);
9fe912ce	236	out_unlock:
48b19268	237	mutex_unlock(&mtd_table_mutex);
9c74034f	238	return ERR_PTR(err);
1da177e4 LT	239	}
1da177e4 LT	240
7799308f AB	241	/**
	242	* get_mtd_device_nm - obtain a validated handle for an MTD device by
	243	* device name
	244	* @name: MTD device name to open
	245	*
	246	* This function returns MTD device description structure in case of
	247	* success and an error code in case of failure.
	248	*/
	249
	250	struct mtd_info get_mtd_device_nm(const char name)
	251	{
9fe912ce AB	252	int i, err = -ENODEV;
9fe912ce AB	253	struct mtd_info *mtd = NULL;
7799308f AB	254
	255	mutex_lock(&mtd_table_mutex);
	256
	257	for (i = 0; i < MAX_MTD_DEVICES; i++) {
	258	if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) {
	259	mtd = mtd_table[i];
	260	break;
	261	}
	262	}
	263
9fe912ce	264	if (!mtd)
7799308f AB	265	goto out_unlock;
	266
	267	if (!try_module_get(mtd->owner))
	268	goto out_unlock;
	269
9fe912ce AB	270	if (mtd->get_device) {
	271	err = mtd->get_device(mtd);
	272	if (err)
	273	goto out_put;
	274	}
	275
7799308f	276	mtd->usecount++;
9fe912ce AB	277	mutex_unlock(&mtd_table_mutex);
9fe912ce AB	278	return mtd;
7799308f	279
9fe912ce AB	280	out_put:
9fe912ce AB	281	module_put(mtd->owner);
7799308f AB	282	out_unlock:
7799308f AB	283	mutex_unlock(&mtd_table_mutex);
9fe912ce	284	return ERR_PTR(err);
7799308f AB	285	}
7799308f AB	286
1da177e4 LT	287	void put_mtd_device(struct mtd_info *mtd)
	288	{
	289	int c;
	290
48b19268	291	mutex_lock(&mtd_table_mutex);
1da177e4	292	c = --mtd->usecount;
9fe912ce AB	293	if (mtd->put_device)
9fe912ce AB	294	mtd->put_device(mtd);
48b19268	295	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	296	BUG_ON(c < 0);
	297
	298	module_put(mtd->owner);
	299	}
	300
	301	/* default_mtd_writev - default mtd writev method for MTD devices that
dd36f267	302	* don't implement their own
1da177e4 LT	303	*/
	304
	305	int default_mtd_writev(struct mtd_info mtd, const struct kvec vecs,
	306	unsigned long count, loff_t to, size_t *retlen)
	307	{
	308	unsigned long i;
	309	size_t totlen = 0, thislen;
	310	int ret = 0;
	311
	312	if(!mtd->write) {
	313	ret = -EROFS;
	314	} else {
	315	for (i=0; i<count; i++) {
	316	if (!vecs[i].iov_len)
	317	continue;
	318	ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base);
	319	totlen += thislen;
	320	if (ret \|\| thislen != vecs[i].iov_len)
	321	break;
	322	to += vecs[i].iov_len;
	323	}
	324	}
	325	if (retlen)
	326	*retlen = totlen;
	327	return ret;
	328	}
	329
dd36f267 DW	330	EXPORT_SYMBOL_GPL(add_mtd_device);
	331	EXPORT_SYMBOL_GPL(del_mtd_device);
	332	EXPORT_SYMBOL_GPL(get_mtd_device);
	333	EXPORT_SYMBOL_GPL(get_mtd_device_nm);
	334	EXPORT_SYMBOL_GPL(put_mtd_device);
	335	EXPORT_SYMBOL_GPL(register_mtd_user);
	336	EXPORT_SYMBOL_GPL(unregister_mtd_user);
	337	EXPORT_SYMBOL_GPL(default_mtd_writev);
1da177e4	338
2d2dce0e PM	339	#ifdef CONFIG_PROC_FS
2d2dce0e PM	340
1da177e4 LT	341	/====================================================================/
	342	/* Support for /proc/mtd */
	343
1da177e4 LT	344	static struct proc_dir_entry *proc_mtd;
	345
	346	static inline int mtd_proc_info (char *buf, int i)
	347	{
	348	struct mtd_info *this = mtd_table[i];
	349
	350	if (!this)
	351	return 0;
	352
	353	return sprintf(buf, "mtd%d: %8.8x %8.8x \"%s\"\n", i, this->size,
	354	this->erasesize, this->name);
	355	}
	356
	357	static int mtd_read_proc (char page, char *start, off_t off, int count,
	358	int eof, void data_unused)
	359	{
	360	int len, l, i;
	361	off_t begin = 0;
	362
48b19268	363	mutex_lock(&mtd_table_mutex);
1da177e4 LT	364
	365	len = sprintf(page, "dev: size erasesize name\n");
	366	for (i=0; i< MAX_MTD_DEVICES; i++) {
	367
	368	l = mtd_proc_info(page + len, i);
	369	len += l;
	370	if (len+begin > off+count)
	371	goto done;
	372	if (len+begin < off) {
	373	begin += len;
	374	len = 0;
	375	}
	376	}
	377
	378	*eof = 1;
	379
	380	done:
48b19268	381	mutex_unlock(&mtd_table_mutex);
1da177e4 LT	382	if (off >= len+begin)
	383	return 0;
	384	*start = page + (off-begin);
	385	return ((count < begin+len-off) ? count : begin+len-off);
	386	}
	387
1da177e4 LT	388	/====================================================================/
	389	/* Init code */
	390
	391	static int __init init_mtd(void)
	392	{
1da177e4 LT	393	if ((proc_mtd = create_proc_entry( "mtd", 0, NULL )))
1da177e4 LT	394	proc_mtd->read_proc = mtd_read_proc;
1da177e4 LT	395	return 0;
	396	}
	397
	398	static void __exit cleanup_mtd(void)
	399	{
1da177e4 LT	400	if (proc_mtd)
1da177e4 LT	401	remove_proc_entry( "mtd", NULL);
1da177e4 LT	402	}
	403
	404	module_init(init_mtd);
	405	module_exit(cleanup_mtd);
	406
2d2dce0e PM	407	#endif /* CONFIG_PROC_FS */
2d2dce0e PM	408
1da177e4 LT	409
	410	MODULE_LICENSE("GPL");
	411	MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
	412	MODULE_DESCRIPTION("Core MTD registration and access routines");