From: Ben Hutchings Date: Fri, 29 Jan 2010 20:58:37 +0000 (+0000) Subject: mtd: mtdblock: Dynamically allocate cache info structures X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=cbfe93e9cedfcd59689bad9e67f57ef67545e5a0;p=openwrt%2Fstaging%2Fblogic.git 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: Ben Hutchings Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- diff --git a/drivers/mtd/mtdblock.c b/drivers/mtd/mtdblock.c index 9f41b1a853c1..69f6bf2e0a8c 100644 --- a/drivers/mtd/mtdblock.c +++ b/drivers/mtd/mtdblock.c @@ -19,15 +19,15 @@ #include -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 = {