on i386 and amd64 machines. The overall process is that /boot/pmbr lives
in the PMBR (similar to /boot/mbr for MBR disks) and is responsible for
locating and loading /boot/gptboot. /boot/gptboot is similar to /boot/boot
except that it groks GPT rather than MBR + bsdlabel. Unlike /boot/boot,
/boot/gptboot lives in its own dedicated GPT partition with a new
"FreeBSD boot" type. This partition does not have a fixed size in that
/boot/pmbr will load the entire partition into the lower 640k. However,
it is limited in that it can only be 545k. That's still a lot better than
the current 7.5k limit for boot2 on MBR. gptboot mostly acts just like
boot2 in that it reads /boot.config and loads up /boot/loader. Some more
details:
- Include uuid_equal() and uuid_is_nil() in libstand.
- Add a new 'boot' command to gpt(8) which makes a GPT disk bootable using
/boot/pmbr and /boot/gptboot. Note that the disk must have some free
space for the boot partition.
- This required exposing the backend of the 'add' function as a
gpt_add_part() function to the rest of gpt(8). 'boot' uses this to
create a boot partition if needed.
- Don't cripple cgbase() in the UFS boot code for /boot/gptboot so that
it can handle a filesystem > 1.5 TB.
- /boot/gptboot has a simple loader (gptldr) that doesn't do any I/O
unlike boot1 since /boot/pmbr loads all of gptboot up front. The
C portion of gptboot (gptboot.c) has been repocopied from boot2.c.
The primary changes are to parse the GPT to find a root filesystem
and to use 64-bit disk addresses. Currently gptboot assumes that the
first UFS partition on the disk is the / filesystem, but this algorithm
will likely be improved in the future.
- Teach the biosdisk driver in /boot/loader to understand GPT tables.
GPT partitions are identified as 'disk0pX:' (e.g. disk0p2:) which is
similar to the /dev names the kernel uses (e.g. /dev/ad0p2).
- Add a new "freebsd-boot" alias to g_part() for the new boot UUID.
MFC after: 1 month
Discussed with: marcel (some things might still change, but am committing
what I have so far)
labeled are selected in the same way as with the remove command.
Update the manpage to have the selection options described for the
label command and referenced to it from the remove command.
The label can be specified on the command line with the -l option
or read from a file with the -f option. In both cases, the label
is assumed to be encoded in UTF-8.
PR: ia64/83124
MFC after: 1 week
command line) and the device path (what we passed to open()). Use
the former in diagnostics.
- when adding or removing partitions, print a single line to stdout for
each partition that was added or removed, indicating its name.
- add an -a option to 'gpt remove' which must be explicitly specified
to remove all partitions.
Approved by: marcel (in prinicple)
MFC after: 2 weeks
allows the user to force the creation of a GPT even when there's a
MBR on the device. The MBR is simply wiped and any partitions
described by it are lost. Without the -f option one cannot create
a GPT when there's a MBR.
the MBR after it is migrated to a GPT. While this was useful during
the early days when GPT support was under development, it's something
that users can use without knowing what they're getting themselves
into. The possible harm outweights the marginal usefulness it now has.
starts at 1. No index is represented by 0.
o Change the show command to display the partition number at the expense
of the partition end columm. We already display the start and size.
o Enhance the add command to accept the -i option. The -i option allows
the user to specify which partition number the new partition should
get.
o Update the manpage accordingly.
