Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r232680: Remove unactionable message about label geometry

It's not clear to a user what they should do after seeing the "geometry
does not match label" kernel message, and it does not appear to present
a problem in practice. Thus, just remove the messages.

MFC r236023 (by marcel):
Add a partition type for nandfs to the apm, bsd, gpt and vtoc8 schemes.
The gpart alias for these partition types is "freebsd-nandfs".

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Change the way how we update bootcode for BSD scheme.
Since the only parameter that we check is size of bootcode, then
allow only two sizes: size of boot1 and size of /boot/boot.
This partially protects users from losing ability to boot if incorrect
bootcode is specified.

Requested by: ru

Limit number of sectors that can be addressed.

MFC after: 1 week

Add some FEATURE macros for various GEOM classes.

No FreeBSD version bump, the userland application to query the features will
be committed last and can serve as an indication of the availablility if
needed.

Sponsored by: Google Summer of Code 2010
Submitted by: kibab
Reviewed by: silence on geom@ during 2 weeks
X-MFC after: to be determined in last commit with code from this project

While inspecting the disklabel check that start offset of partition is
within provider's bounds. If not then reject this disklabel.
Mark bbarea as NULL to do not free it again in destroy method.

MFC after: 1 week

Add a note about the magic number 20. Actually, 22.75 entries fit in
a 512 byte sector but when choosing magic numbers, 20 looks nicer.

Discussed with: marcel

Don't leak memory on destruction.

Reviewed by: marcel
MFC after: 3 days

Implement the resize verb and add support for resizing partitions
for all schemes but EBR. Quality work by Andrey!

Submitted by: "Andrey V. Elsukov" <bu7cher@yandex.ru>

Remove unneeded variables.

Found with: clang

Sharpen the saw:
o BSD uses 32-bit block numbers. Limit the scheme to 2^32-1
blocks when the media is larger.

Add bootcode handling.

Fix g_part_*dumpconf to return void to match kobj definition.
Fix g_part_*name to return a const char * rather than a char *.

When the geometry does not match the label, print out the values.

Allow dumpon to a partition of type FS_UNUSED as well.

Partition type FS_UNUSED does not mean the partition entry
is unused. Unused partition entries have a partition size
of zero. Therefore, partitions can have type FS_UNUSED.

MFC after: 3 days

Invalid BSD disklabels have been created by sysinstall and
are possibly still being created. The d_secperunit field
contains the number of sectors of the disk and not of the
slice/partition to which the disklabel applies.
Rather than reject the disklabel, we now silently adjust
the field. Existing code, like bslabel(8), does not seem
to check the label that extensively and seems to adjust
fields as a side-effect as well.
In other words, it's not that important apparently, so
gpart should not be too strict about it.

Reported by: nyan@
Reported by: Andriy Gapon <avg@icyb.net.ua>

Return G_PART_PROBE_PRI_HIGH instead of G_PART_PROBE_PRI_NORM
if the probe succeeds. This guarantees that the BSD scheme
wins over the MBR scheme when MBR gets to probe first. Build-
or link-time conditions can cause schemes to end up in the
linker set in a different order. Normally BSD is before MBR
in the linker set and as such get to probe first. But typically
when the kernel gets rebuild or relinked, this can change.

Allow 255 sectors/track for the BSD disklabel. The previous limit
of 63 sectors/track is too PC BIOS specific. On pc98, where the
BSD disklabel is used as well, 255 sectors/track is not uncommon.

Submitted by: nyan@

Add the raw partition type to the XML.

Implement the G_PART_DUMPCONF method for all 6 schemes. Also call
the method for the (indent == NULL) case (i.e. the kern.geom.conftxt
sysctl). The purpose is to extend the conftxt output with scheme-
specific fields which can be used by libdisk. In particular, have
the schemes dump the xs and xt fields, which contain the backward
compatible values for class type and partition type. This allows
libdisk to work with the legacy slicers as well as with gpart and
helps/promotes migration.

Redefine G_PART_SCHEME_DECLARE() from populating a private linker set
to declaring a proper module. The module event handler is part of the
gpart core and will add the scheme to an internal list on module load
and will remove the scheme from the internal list on module unload.
This makes it possible to dynamically load and unload partitioning
schemes.

Various fixes:
o BSD disklabels have relative offsets. Even for the BSD in MBR slice
setup, except when the mbroffset ioctl is supported. Since we don't
support that ioctl, bsdlabel(8) expects relative offsets. So, when
reading an existing disklabel, correct for disklabels that mistakenly
have the mbroffset offsets.
o Don't take the geometry seriously, because it's untrustworthy. We do
expect the numbers to be within range. This means that the secperunit
field will not be computed from secpercyl and ncyls, but simply is
the mediasize in sectors.
o Don't enforce partitions to be aligned to track boundaries. The
default label, constructed by bsdlabel(8), puts partition a at offset
BBSIZE bytes, which commonly means sector 16.

Add support for FS_ZFS.

Add a BSD disklabel backend to g_part:
o Disklabels can have between 8 and 20 partitions (inclusive).
o No device special file is created for the raw partition.
o Switch ia64 to use this backend.
o No support for boot code yet.