block: don't depend on consecutive minor space

* Implement disk_devt() and part_devt() and use them to directly
  access devt instead of computing it from ->major and ->first_minor.

  Note that all references to ->major and ->first_minor outside of
  block layer is used to determine devt of the disk (the part0) and as
  ->major and ->first_minor will continue to represent devt for the
  disk, converting these users aren't strictly necessary.  However,
  convert them for consistency.

* Implement disk_max_parts() to avoid directly deferencing
  genhd->minors.

* Update bdget_disk() such that it doesn't assume consecutive minor
  space.

* Move devt computation from register_disk() to add_disk() and make it
  the only one (all other usages use the initially determined value).

These changes clean up the code and will help disk->part dereference
fix and extended block device numbers.

Signed-off-by: Tejun Heo <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
This commit is contained in:
Tejun Heo 2008-09-03 09:01:48 +02:00 • committed by Jens Axboe
commit f331c0296f
16 changed files with 132 additions and 67 deletions

View file

@ -197,7 +197,7 @@ static int mspro_block_bd_open(struct inode *inode, struct file *filp)
static int mspro_block_disk_release(struct gendisk *disk)
{
struct mspro_block_data *msb = disk->private_data;
int disk_id = disk->first_minor >> MSPRO_BLOCK_PART_SHIFT;
int disk_id = MINOR(disk_devt(disk)) >> MSPRO_BLOCK_PART_SHIFT;
mutex_lock(&mspro_block_disk_lock);