Correct some issues with zfs boot.
- Teach it to read gang blocks. (essentially untested)
If you see "ZFS: gang block detected!", please let
me know, so we can either remove the printf if it
works, or fix it if it doesn't.
- If multiple partitions exist on a disk, probe them all.
We also need to reset dsk->start to 0 to read the right
sector here.
- With GPT, we can have 128 partitions.
- If the bootfs property has ever been set on a pool
it seems that it never goes away. zpool won't allow
you to add to the pool with the bootfs property set.
However, if you clear the property back to default
we end up getting 0 for the object number and read
a bogus block pointer and fail to boot.
- Fix some error printfs. The printf in the loader is
only capable of c,s and u formats.
- Teach printf how to display %llu
to gptboot, i.e. installed in a freebsd-boot partition using /sbin/gpart or
/sbin/gpt.
Tweak the /boot/loader ZFS support so that it can find ZFS pools that are
contained in GPT partitions.
This bring huge amount of changes, I'll enumerate only user-visible changes:
- Delegated Administration
Allows regular users to perform ZFS operations, like file system
creation, snapshot creation, etc.
- L2ARC
Level 2 cache for ZFS - allows to use additional disks for cache.
Huge performance improvements mostly for random read of mostly
static content.
- slog
Allow to use additional disks for ZFS Intent Log to speed up
operations like fsync(2).
- vfs.zfs.super_owner
Allows regular users to perform privileged operations on files stored
on ZFS file systems owned by him. Very careful with this one.
- chflags(2)
Not all the flags are supported. This still needs work.
- ZFSBoot
Support to boot off of ZFS pool. Not finished, AFAIK.
Submitted by: dfr
- Snapshot properties
- New failure modes
Before if write requested failed, system paniced. Now one
can select from one of three failure modes:
- panic - panic on write error
- wait - wait for disk to reappear
- continue - serve read requests if possible, block write requests
- Refquota, refreservation properties
Just quota and reservation properties, but don't count space consumed
by children file systems, clones and snapshots.
- Sparse volumes
ZVOLs that don't reserve space in the pool.
- External attributes
Compatible with extattr(2).
- NFSv4-ACLs
Not sure about the status, might not be complete yet.
Submitted by: trasz
- Creation-time properties
- Regression tests for zpool(8) command.
Obtained from: OpenSolaris
