Commit cbfe93e9 authored by Ben Hutchings's avatar Ben Hutchings Committed by David Woodhouse
Browse files

mtd: mtdblock: Dynamically allocate cache info structures 



Since we allocate struct mtd_blktrans_dev for each block device, we
can add our own structure members to the end.  Therefore embed
struct mtd_blktrans_dev in struct mtdblk_dev and remove the static
array of struct mtdblk_dev.  Also remove the redundant pointer to
struct mtd_info.

This is preparation for removing the static limit on the number of MTD
devices.

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 24c15496

drivers/mtd/mtdblock.c

+31 −43
Original line number Diff line number Diff line
@@ -19,15 +19,15 @@ 
#include <linux/mutex.h>





static struct mtdblk_dev {

	struct mtd_info *mtd;

struct mtdblk_dev {

	struct mtd_blktrans_dev mbd;

	int count;

	struct mutex cache_mutex;

	unsigned char *cache_data;

	unsigned long cache_offset;

	unsigned int cache_size;

	enum { STATE_EMPTY, STATE_CLEAN, STATE_DIRTY } cache_state;

} *mtdblks[MAX_MTD_DEVICES];

};



static struct mutex mtdblks_lock;
@@ -98,7 +98,7 @@ static int erase_write (struct mtd_info *mtd, unsigned long pos, 


static int write_cached_data (struct mtdblk_dev *mtdblk)

{

	struct mtd_info *mtd = mtdblk->mtd;

	struct mtd_info *mtd = mtdblk->mbd.mtd;

	int ret;



	if (mtdblk->cache_state != STATE_DIRTY)
@@ -128,7 +128,7 @@ static int write_cached_data (struct mtdblk_dev *mtdblk) 
static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos,

			    int len, const char *buf)

{

	struct mtd_info *mtd = mtdblk->mtd;

	struct mtd_info *mtd = mtdblk->mbd.mtd;

	unsigned int sect_size = mtdblk->cache_size;

	size_t retlen;

	int ret;
@@ -198,7 +198,7 @@ static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, 
static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos,

			   int len, char *buf)

{

	struct mtd_info *mtd = mtdblk->mtd;

	struct mtd_info *mtd = mtdblk->mbd.mtd;

	unsigned int sect_size = mtdblk->cache_size;

	size_t retlen;

	int ret;
@@ -244,16 +244,16 @@ static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, 
static int mtdblock_readsect(struct mtd_blktrans_dev *dev,

			      unsigned long block, char *buf)

{

	struct mtdblk_dev *mtdblk = mtdblks[dev->devnum];

	struct mtdblk_dev *mtdblk = container_of(dev, struct mtdblk_dev, mbd);

	return do_cached_read(mtdblk, block<<9, 512, buf);

}



static int mtdblock_writesect(struct mtd_blktrans_dev *dev,

			      unsigned long block, char *buf)

{

	struct mtdblk_dev *mtdblk = mtdblks[dev->devnum];

	struct mtdblk_dev *mtdblk = container_of(dev, struct mtdblk_dev, mbd);

	if (unlikely(!mtdblk->cache_data && mtdblk->cache_size)) {

		mtdblk->cache_data = vmalloc(mtdblk->mtd->erasesize);

		mtdblk->cache_data = vmalloc(mtdblk->mbd.mtd->erasesize);

		if (!mtdblk->cache_data)

			return -EINTR;

		/* -EINTR is not really correct, but it is the best match
@@ -266,37 +266,26 @@ static int mtdblock_writesect(struct mtd_blktrans_dev *dev, 


static int mtdblock_open(struct mtd_blktrans_dev *mbd)

{

	struct mtdblk_dev *mtdblk;

	struct mtd_info *mtd = mbd->mtd;

	int dev = mbd->devnum;

	struct mtdblk_dev *mtdblk = container_of(mbd, struct mtdblk_dev, mbd);



	DEBUG(MTD_DEBUG_LEVEL1,"mtdblock_open\n");



	mutex_lock(&mtdblks_lock);

	if (mtdblks[dev]) {

		mtdblks[dev]->count++;

	if (mtdblk->count) {

		mtdblk->count++;

		mutex_unlock(&mtdblks_lock);

		return 0;

	}



	/* OK, it's not open. Create cache info for it */

	mtdblk = kzalloc(sizeof(struct mtdblk_dev), GFP_KERNEL);

	if (!mtdblk) {

		mutex_unlock(&mtdblks_lock);

		return -ENOMEM;

	}



	mtdblk->count = 1;

	mtdblk->mtd = mtd;



	mutex_init(&mtdblk->cache_mutex);

	mtdblk->cache_state = STATE_EMPTY;

	if ( !(mtdblk->mtd->flags & MTD_NO_ERASE) && mtdblk->mtd->erasesize) {

		mtdblk->cache_size = mtdblk->mtd->erasesize;

	if (!(mbd->mtd->flags & MTD_NO_ERASE) && mbd->mtd->erasesize) {

		mtdblk->cache_size = mbd->mtd->erasesize;

		mtdblk->cache_data = NULL;

	}



	mtdblks[dev] = mtdblk;

	mutex_unlock(&mtdblks_lock);



	DEBUG(MTD_DEBUG_LEVEL1, "ok\n");
@@ -306,8 +295,7 @@ static int mtdblock_open(struct mtd_blktrans_dev *mbd) 


static int mtdblock_release(struct mtd_blktrans_dev *mbd)

{

	int dev = mbd->devnum;

	struct mtdblk_dev *mtdblk = mtdblks[dev];

	struct mtdblk_dev *mtdblk = container_of(mbd, struct mtdblk_dev, mbd);



   	DEBUG(MTD_DEBUG_LEVEL1, "mtdblock_release\n");
@@ -318,12 +306,10 @@ static int mtdblock_release(struct mtd_blktrans_dev *mbd) 
	mutex_unlock(&mtdblk->cache_mutex);



	if (!--mtdblk->count) {

		/* It was the last usage. Free the device */

		mtdblks[dev] = NULL;

		if (mtdblk->mtd->sync)

			mtdblk->mtd->sync(mtdblk->mtd);

		/* It was the last usage. Free the cache */

		if (mbd->mtd->sync)

			mbd->mtd->sync(mbd->mtd);

		vfree(mtdblk->cache_data);

		kfree(mtdblk);

	}



	mutex_unlock(&mtdblks_lock);
@@ -335,40 +321,42 @@ static int mtdblock_release(struct mtd_blktrans_dev *mbd) 


static int mtdblock_flush(struct mtd_blktrans_dev *dev)

{

	struct mtdblk_dev *mtdblk = mtdblks[dev->devnum];

	struct mtdblk_dev *mtdblk = container_of(dev, struct mtdblk_dev, mbd);



	mutex_lock(&mtdblk->cache_mutex);

	write_cached_data(mtdblk);

	mutex_unlock(&mtdblk->cache_mutex);



	if (mtdblk->mtd->sync)

		mtdblk->mtd->sync(mtdblk->mtd);

	if (dev->mtd->sync)

		dev->mtd->sync(dev->mtd);

	return 0;

}



static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)

{

	struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);

	struct mtdblk_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);



	if (!dev)

		return;



	dev->mtd = mtd;

	dev->devnum = mtd->index;

	dev->mbd.mtd = mtd;

	dev->mbd.devnum = mtd->index;



	dev->size = mtd->size >> 9;

	dev->tr = tr;

	dev->mbd.size = mtd->size >> 9;

	dev->mbd.tr = tr;



	if (!(mtd->flags & MTD_WRITEABLE))

		dev->readonly = 1;

		dev->mbd.readonly = 1;



	add_mtd_blktrans_dev(dev);

	add_mtd_blktrans_dev(&dev->mbd);

}



static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)

{

	struct mtdblk_dev *mtdblk = container_of(dev, struct mtdblk_dev, mbd);



	del_mtd_blktrans_dev(dev);

	kfree(dev);

	kfree(mtdblk);

}



static struct mtd_blktrans_ops mtdblock_tr = {

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