diff options
author | Tejun Heo <tj@kernel.org> | 2008-08-25 19:56:17 +0900 |
---|---|---|
committer | Jens Axboe <jens.axboe@oracle.com> | 2008-08-29 09:08:13 +0200 |
commit | b39286481fd7b7ca1ca9ae898adfad2eeec64f5b (patch) | |
tree | 384885411d40b7251f0c0c7b729a02517e4b31f7 /block | |
parent | 195e876a842c232e0978622736cdc15f2967a2e7 (diff) |
block: allow disk to have extended device number
Now that disk and partition handlings are mostly unified, it's easy to
allow disk to have extended device number. This patch makes
add_disk() use extended device number if disk->minors is zero. Both
sd and ide-disk are updated to use this.
* sd_format_disk_name() is implemented which can generically determine
the drive name. This removes disk number restriction stemming from
limited device names.
* If sd index goes over SD_MAX_DISKS (which can be increased now BTW),
sd simply doesn't initialize minors letting block layer choose
extended device number.
* If CONFIG_DEBUG_EXT_DEVT is set, both sd and ide-disk always set
minors to 0 and use extended device numbers.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/genhd.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/block/genhd.c b/block/genhd.c index fc02c651d688..35ece0084f85 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -478,14 +478,37 @@ static int exact_lock(dev_t devt, void *data) * * This function registers the partitioning information in @disk * with the kernel. + * + * FIXME: error handling */ void add_disk(struct gendisk *disk) { struct backing_dev_info *bdi; + dev_t devt; int retval; + /* minors == 0 indicates to use ext devt from part0 and should + * be accompanied with EXT_DEVT flag. Make sure all + * parameters make sense. + */ + WARN_ON(disk->minors && !(disk->major || disk->first_minor)); + WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT)); + disk->flags |= GENHD_FL_UP; - disk_to_dev(disk)->devt = MKDEV(disk->major, disk->first_minor); + + retval = blk_alloc_devt(&disk->part0, &devt); + if (retval) { + WARN_ON(1); + return; + } + disk_to_dev(disk)->devt = devt; + + /* ->major and ->first_minor aren't supposed to be + * dereferenced from here on, but set them just in case. + */ + disk->major = MAJOR(devt); + disk->first_minor = MINOR(devt); + blk_register_region(disk_devt(disk), disk->minors, NULL, exact_match, exact_lock, disk); register_disk(disk); |