diff options
| -rw-r--r-- | Documentation/devices.txt | 6 | ||||
| -rw-r--r-- | drivers/mmc/card/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/mmc/card/block.c | 43 |
3 files changed, 54 insertions, 12 deletions
diff --git a/Documentation/devices.txt b/Documentation/devices.txt index c58abf1ccc7..170cc1e7e13 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt @@ -2520,6 +2520,12 @@ Your cooperation is appreciated. 8 = /dev/mmcblk1 Second SD/MMC card ... + The start of next SD/MMC card can be configured with + CONFIG_MMC_BLOCK_MINORS, or overridden at boot/modprobe + time using the mmcblk.perdev_minors option. That would + bump the offset between each card to be the configured + value instead of the default 8. + 179 char CCube DVXChip-based PCI products 0 = /dev/dvxirq0 First DVX device 1 = /dev/dvxirq1 Second DVX device diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig index 3f2a912659a..57e4416b9ef 100644 --- a/drivers/mmc/card/Kconfig +++ b/drivers/mmc/card/Kconfig @@ -14,6 +14,23 @@ 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 4 256 + default 8 + help + Number of minors per block device. One is needed for every + partition on the disk (plus one for the whole disk). + + Number of total MMC minors available is 256, so your number + of supported block devices will be limited to 256 divided + by this number. + + Default is 8 to be backwards compatible with previous + hardwired device numbering. + + If unsure, say 8 here. + 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 a9970504cab..217f82037fc 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -43,15 +43,27 @@ #include "queue.h" MODULE_ALIAS("mmc:block"); +#ifdef MODULE_PARAM_PREFIX +#undef MODULE_PARAM_PREFIX +#endif +#define MODULE_PARAM_PREFIX "mmcblk." + +static DEFINE_MUTEX(block_mutex); /* - * max 8 partitions per card + * The defaults come from config options but can be overriden by module + * or bootarg options. */ -#define MMC_SHIFT 3 -#define MMC_NUM_MINORS (256 >> MMC_SHIFT) +static int perdev_minors = CONFIG_MMC_BLOCK_MINORS; -static DEFINE_MUTEX(block_mutex); -static DECLARE_BITMAP(dev_use, MMC_NUM_MINORS); +/* + * We've only got one major, so number of mmcblk devices is + * limited to 256 / number of minors per device. + */ +static int max_devices; + +/* 256 minors, so at most 256 separate devices */ +static DECLARE_BITMAP(dev_use, 256); /* * There is one mmc_blk_data per slot. @@ -67,6 +79,9 @@ struct mmc_blk_data { static DEFINE_MUTEX(open_lock); +module_param(perdev_minors, int, 0444); +MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device"); + static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk) { struct mmc_blk_data *md; @@ -88,10 +103,10 @@ 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)) / perdev_minors; if (!devmaj) - devidx = md->disk->first_minor >> MMC_SHIFT; + devidx = md->disk->first_minor / perdev_minors; blk_cleanup_queue(md->queue.queue); @@ -566,8 +581,8 @@ 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, max_devices); + if (devidx >= max_devices) return ERR_PTR(-ENOSPC); __set_bit(devidx, dev_use); @@ -584,7 +599,7 @@ 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(perdev_minors); if (md->disk == NULL) { ret = -ENOMEM; goto err_kfree; @@ -601,7 +616,7 @@ 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 * perdev_minors; md->disk->fops = &mmc_bdops; md->disk->private_data = md; md->disk->queue = md->queue.queue; @@ -670,7 +685,6 @@ static int mmc_blk_probe(struct mmc_card *card) { struct mmc_blk_data *md; int err; - char cap_str[10]; /* @@ -760,6 +774,11 @@ static int __init mmc_blk_init(void) { int res; + if (perdev_minors != CONFIG_MMC_BLOCK_MINORS) + pr_info("mmcblk: using %d minors per device\n", perdev_minors); + + max_devices = 256 / perdev_minors; + res = register_blkdev(MMC_BLOCK_MAJOR, "mmc"); if (res) goto out; |