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 <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Tejun Heo
2008-09-03 09:01:48 +02:00
committed by Jens Axboe
parent cf771cb5a7
commit f331c0296f
16 changed files with 132 additions and 67 deletions

View File

@ -426,7 +426,7 @@ static int list_devices(struct dm_ioctl *param, size_t param_size)
old_nl->next = (uint32_t) ((void *) nl -
(void *) old_nl);
disk = dm_disk(hc->md);
nl->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
nl->dev = huge_encode_dev(disk_devt(disk));
nl->next = 0;
strcpy(nl->name, hc->name);
@ -539,7 +539,7 @@ static int __dev_status(struct mapped_device *md, struct dm_ioctl *param)
if (dm_suspended(md))
param->flags |= DM_SUSPEND_FLAG;
param->dev = huge_encode_dev(MKDEV(disk->major, disk->first_minor));
param->dev = huge_encode_dev(disk_devt(disk));
/*
* Yes, this will be out of date by the time it gets back