Commit b520e412 authored by Ben Hutchings's avatar Ben Hutchings Committed by David Woodhouse
Browse files

mtd: Replace static array of devices with an idr structure 



Signed-off-by: default avatarBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent 4d1ee80f

drivers/mtd/mtdcore.c

+80 −71
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/init.h>

#include <linux/mtd/compatmac.h>

#include <linux/proc_fs.h>

#include <linux/idr.h>



#include <linux/mtd/mtd.h>

#include "internal.h"
@@ -33,13 +34,18 @@ static struct class mtd_class = { 
	.resume = mtd_cls_resume,

};



static DEFINE_IDR(mtd_idr);



/* 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);



struct mtd_info *__mtd_next_device(int i)

{

	return idr_get_next(&mtd_idr, &i);

}

EXPORT_SYMBOL_GPL(__mtd_next_device);



static LIST_HEAD(mtd_notifiers);
@@ -235,13 +241,13 @@ static struct device_type mtd_devtype = { 
 *	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)

 *	or there's a sysfs error.

 *	if there is insufficient memory or a sysfs error.

 */



int add_mtd_device(struct mtd_info *mtd)

{

	int i;

	struct mtd_notifier *not;

	int i, error;



	if (!mtd->backing_dev_info) {

		switch (mtd->type) {
@@ -260,11 +266,15 @@ int add_mtd_device(struct mtd_info *mtd) 
	BUG_ON(mtd->writesize == 0);

	mutex_lock(&mtd_table_mutex);



	for (i=0; i < MAX_MTD_DEVICES; i++)

		if (!mtd_table[i]) {

			struct mtd_notifier *not;

	do {

		if (!idr_pre_get(&mtd_idr, GFP_KERNEL))

			goto fail_locked;

		error = idr_get_new(&mtd_idr, mtd, &i);

	} while (error == -EAGAIN);



	if (error)

		goto fail_locked;



			mtd_table[i] = mtd;

	mtd->index = i;

	mtd->usecount = 0;
@@ -286,8 +296,7 @@ int add_mtd_device(struct mtd_info *mtd) 
	    && (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",

			       "%s: unlock failed, writes may not work\n",

			       mtd->name);

	}
@@ -299,10 +308,8 @@ int add_mtd_device(struct mtd_info *mtd) 
	mtd->dev.devt = MTD_DEVT(i);

	dev_set_name(&mtd->dev, "mtd%d", i);

	dev_set_drvdata(&mtd->dev, mtd);

			if (device_register(&mtd->dev) != 0) {

				mtd_table[i] = NULL;

				break;

			}

	if (device_register(&mtd->dev) != 0)

		goto fail_added;



	if (MTD_DEVT(i))

		device_create(&mtd_class, mtd->dev.parent,
@@ -322,8 +329,10 @@ int add_mtd_device(struct mtd_info *mtd) 
	   either. :) */

	__module_get(THIS_MODULE);

	return 0;

		}



fail_added:

	idr_remove(&mtd_idr, i);

fail_locked:

	mutex_unlock(&mtd_table_mutex);

	return 1;

}
@@ -344,7 +353,7 @@ int del_mtd_device (struct mtd_info *mtd) 


	mutex_lock(&mtd_table_mutex);



	if (mtd_table[mtd->index] != mtd) {

	if (idr_find(&mtd_idr, mtd->index) != mtd) {

		ret = -ENODEV;

	} else if (mtd->usecount) {

		printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
@@ -360,7 +369,7 @@ int del_mtd_device (struct mtd_info *mtd) 
		list_for_each_entry(not, &mtd_notifiers, list)

			not->remove(mtd);



		mtd_table[mtd->index] = NULL;

		idr_remove(&mtd_idr, mtd->index);



		module_put(THIS_MODULE);

		ret = 0;
@@ -448,8 +457,8 @@ struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) 
				break;

			}

		}

	} else if (num >= 0 && num < MAX_MTD_DEVICES) {

		ret = mtd_table[num];

	} else if (num >= 0) {

		ret = idr_find(&mtd_idr, num);

		if (mtd && mtd != ret)

			ret = NULL;

	}

drivers/mtd/mtdcore.h

+1 −11
Original line number Diff line number Diff line
@@ -8,17 +8,7 @@ 
   should not use them for _anything_ else */



extern struct mutex mtd_table_mutex;

extern struct mtd_info *mtd_table[MAX_MTD_DEVICES];



static inline struct mtd_info *__mtd_next_device(int i)

{

	while (i < MAX_MTD_DEVICES) {

		if (mtd_table[i])

			return mtd_table[i];

		i++;

	}

	return NULL;

}

extern struct mtd_info *__mtd_next_device(int i);



#define mtd_for_each_device(mtd)			\

	for ((mtd) = __mtd_next_device(0);		\

include/linux/mtd/mtd.h

+0 −1
Original line number Diff line number Diff line
@@ -20,7 +20,6 @@ 


#define MTD_CHAR_MAJOR 90

#define MTD_BLOCK_MAJOR 31

#define MAX_MTD_DEVICES 32



#define MTD_ERASE_PENDING      	0x01

#define MTD_ERASING		0x02