1ee8f4a418
config_handle_wedges() and read_disk_sectors(). On x86, handle_wedges()
is a thin wrapper for config_handle_wedges(). Share opendisk()
across architectures.
Add kernel code in support of specifying a root partition by wedge
name. E.g., root specifications "wedge:wd0a", "wedge:David's Root
Volume" are possible. (Patches for config(1) coming soon.)
In support of moving disks between architectures (esp. i386 <->
evbmips), I've written a routine convertdisklabel() that ensures
that the raw partition is at RAW_DISK by following these steps:
0 If we have read a disklabel that has a RAW_PART with
p_offset == 0 and p_size != 0, then use that raw partition.
1 If we have read a disklabel that has both partitions 'c'
and 'd', and RAW_PART has p_offset != 0 or p_size == 0,
but the other partition is suitable for a raw partition
(p_offset == 0, p_size != 0), then swap the two partitions
and use the new raw partition.
2 If the architecture's raw partition is 'd', and if there
is no partition 'd', but there is a partition 'c' that
is suitable for a raw partition, then copy partition 'c'
to partition 'd'.
3 Determine the drive's last sector, using either the
d_secperunit the drive reported, or by guessing (0x1fffffff).
If we cannot read the drive's last sector, then fail.
4 If we have read a disklabel that has no partition slot
RAW_PART, then create a partition RAW_PART. Make it span
the whole drive.
5 If there are fewer than MAXPARTITIONS partitions,
then "slide" the unsuitable raw partition RAW_PART, and
subsequent partitions, into partition slots RAW_PART+1
and subsequent slots. Create a raw partition at RAW_PART.
Make it span the whole drive.
The convertdisklabel() procedure can probably stand to be simplified,
but it ought to deal with all but an extraordinarily broken disklabel,
now.
i386: compiled and tested, sparc64: compiled, evbmips: compiled.