mmc: make number of mmcblk minors configurable

Commit Message

Olof Johansson Aug. 18, 2010, 4:13 a.m. UTC

None

Patch

diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
index 3f2a912..e939dcf 100644
--- a/drivers/mmc/card/Kconfig
+++ b/drivers/mmc/card/Kconfig
@@ -14,6 +14,16 @@  config MMC_BLOCK
 	  mount the filesystem. Almost everyone wishing MMC support
 	  should say Y or M here.
 
+config MMC_BLOCK_MINORS
+	int "Number of minors per block device"
+	range 4 32
+	default 8
+	help
+	  Number of minors per block device. One is needed for every
+	  partition (plus one for the whole device).
+	  Default is 8 to be backwards compatible with previous
+	  hardcoded device numbering.
+
 config MMC_BLOCK_BOUNCE
 	bool "Use bounce buffer for simple hosts"
 	depends on MMC_BLOCK
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index d545f79..524e232 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -45,13 +45,9 @@ 
 
 MODULE_ALIAS("mmc:block");
 
-/*
- * max 8 partitions per card
- */
-#define MMC_SHIFT	3
-#define MMC_NUM_MINORS	(256 >> MMC_SHIFT)
+#define MMC_MAX_DEVICES	((255 + CONFIG_MMC_BLOCK_MINORS) / CONFIG_MMC_BLOCK_MINORS)
 
-static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS);
+static DECLARE_BITMAP(dev_use, MMC_MAX_DEVICES);
 
 /*
  * There is one mmc_blk_data per slot.
@@ -88,10 +84,10 @@  static void mmc_blk_put(struct mmc_blk_data *md)
 	md->usage--;
 	if (md->usage == 0) {
 		int devmaj = MAJOR(disk_devt(md->disk));
-		int devidx = MINOR(disk_devt(md->disk)) >> MMC_SHIFT;
+		int devidx = MINOR(disk_devt(md->disk)) / CONFIG_MMC_BLOCK_MINORS;
 
 		if (!devmaj)
-			devidx = md->disk->first_minor >> MMC_SHIFT;
+			devidx = md->disk->first_minor / CONFIG_MMC_BLOCK_MINORS;
 
 		blk_cleanup_queue(md->queue.queue);
 
@@ -567,8 +563,8 @@  static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
 	struct mmc_blk_data *md;
 	int devidx, ret;
 
-	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
-	if (devidx >= MMC_NUM_MINORS)
+	devidx = find_first_zero_bit(dev_use, MMC_MAX_DEVICES);
+	if (devidx >= MMC_MAX_DEVICES)
 		return ERR_PTR(-ENOSPC);
 	__set_bit(devidx, dev_use);
 
@@ -585,7 +581,7 @@  static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
 	 */
 	md->read_only = mmc_blk_readonly(card);
 
-	md->disk = alloc_disk(1 << MMC_SHIFT);
+	md->disk = alloc_disk(CONFIG_MMC_BLOCK_MINORS);
 	if (md->disk == NULL) {
 		ret = -ENOMEM;
 		goto err_kfree;
@@ -602,7 +598,7 @@  static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
 	md->queue.data = md;
 
 	md->disk->major	= MMC_BLOCK_MAJOR;
-	md->disk->first_minor = devidx << MMC_SHIFT;
+	md->disk->first_minor = devidx * CONFIG_MMC_BLOCK_MINORS;
 	md->disk->fops = &mmc_bdops;
 	md->disk->private_data = md;
 	md->disk->queue = md->queue.queue;