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: r236579

The workaround added in r151650 for handling firmwares that don't allow
a single device to be opened multiple times concurrently unfortunately
isn't sufficient with ZFS. This is due to the fact, that ZFS may open
different partitions of a single device simultaneously. So the best we
can do in this case is to cache the lastly used device path and close
and open devices in ofwd_strategy() as needed.

PR: 165025
Submitted by: Gavin Mu

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

Approved by: re (implicit)

(S)LIST_HEAD_INITIALIZER takes a (S)LIST_HEAD as an argument.
Fix some wrong usages.
Note: this does not affect generated binaries as this argument is not used.

PR: 137213
Submitted by: Eygene Ryabinkin (initial version)
MFC after: 1 month

Don't close OF disk devices on PowerPC. This fixes loader when booting from
disk on my Blue & White G3 system.

- Add a workaround for the fact that OFW doesn't guarantee that
devices can be opened multiple times simultaneously but we're
expected to be able to do so by the rest of the loader.
This fixes booting from disks attached to the on-board SCSI
controller of Sun Ultra 1 (previously this triggered a trap)
and probably also of AX1115 boards.
- While here, remove unused variables and add empty lines where
style(9) requires such.

Tested on: powerpc (grehan), sparc64
MFC after: 1 month

Start each of the license/copyright comments with /*-

Convert to __FBSDID.

Use daddr_t instead of u_long for byte offset in strategy
routine to avoid >4G truncation on 32-bit systems.

no objection by: sparc64

Cut&Paste considered far too easy:

Don't include <sys/disklabel.h>

Change the device path representation in libofw to use the full firmware
path, instead of an internal i386 specific one. Don't try to interpret
a disklabel in ofw_disk.c, open the partition's device node directly and
let the firmware do it. This fixes booting from a partition other than 'a'
on sparc64, which is needed to support more installation methods.

No objection: ppc

Major rework of how we copy data into kernel space.

We now talk to the memory and mmu instances directly rather than using the
OpenFirmware "claim" method.

Change the disk probing so that it will actually find disks other
than the first one on a controller, and work for secondary
controllers.
Due to the prom not having nodes for each disk, but a catch-all one,
we have to iterate over each device, trying to open it to determine
whether it is actually present.
Since probing this way takese some time (and spews some spurious
warnings), it should maybe be short-circuited if we use the
device we were booted from.
Implement lazy device probing, and correct slice/partiniton
handling in the ofwd_open() code. With this, I can now actually boot
a kernel from disk, and the loader does not create unnecessary
delays.

Submitted by: tmm

- Remove unneeded variable.
- Remove change for my local configuration that slipped in with
the last commit; I am having problems booting when multiple SCSI
disks are attached, so I will change this part as soon as I find
a solution, anyway.

- Do not include a NetBSD header as it is not needed anymore.
- Remove two constants that were needed in conjuction with the
NetBSD disklabel header. Use the FreeBSD equivalents.
To boot from NetBSD/sparc64 partitions, define LABELOFFSET to
be 128.
- Do not use the complete open firmware path to filter out cdrom drives.
No path containing "cdrom" is detected as a disk now.
- Simplify some code.

- Fill dummy functions with code to read from disk using Open
Firmware.
- Add a temporary disklabel header to boot off a NetBSD/sparc64
partition. This file can be deleted when we have got a FCode
bootblock.

The disklabel header was obtained from NetBSD.

OpenFirmware/PowerPC loader, part 2.

As of this patchset, the loader builds (under NetBSD/macppc), boots, interacts
and talks to BOOTP/NFS servers.

(main.c was moved from boot/ofw/libofw to boot/ofw/common but has no revision
history)

Reviewed by: obrien

"Ok, my loader's now up to putting up a prompt. It probes disks partially
but can't boot from them yet."

Thanks to Stephane Potvin for the some of the code in this set.

Submitted by: Benno Rice <benno@jeamland.net>