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)
partition size. On 32-bit platforms sizeof(long) < sizeof(off_t)
and using strtol(3) would prevent partitions larger than 4G
sectors or beyond 4G blocks.
PR: bin/103991
MFC after: 3 days
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
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.
UUIDs can then be limited to those cases when an alias doesn't exist.
This greatly increases the likelyhood that a sysadmin finishes the
partitioning without intermittent mental breakdowns. Current aliases
are "efi", "swap" and "ufs".
While here, staticize global variables and expand the usage message.
Approved by: re (blanket)
<sys/gpt.h>. This avoids having to include both <sys/uuid.h> and
<uuid.h>, which is considered by your friendly committer to be
aestheticly displeasing (= ballyhoo barf barf :-)
o Use DCE compliant UUID functions and provide local
implementations if they don't exist,
o Move dumping of the map to show.c and print the
partition type,
o Some cleanups and rearrangements.
The default GPT partition type is UFS. When no starting block
or size are specified, the tool will create a partition in the
first free space it find (or that fits, depending on the size).
