Add initial support for booting from ZFS on sparc64. At least on Sun Fire

V100, the firmware is known to be broken and not allowing to simultaneously
open disk devices, causing attempts to boot from a mirror or RAIDZ to cause
a crash. This will be worked around later. The firmwares of newer sun4u models
don't seem to exhibit this problem though.

Steps for ZFS booting:

1. create VTOC8 label
# gpart create -s vtoc8 da0

2. add partitions, f.e.:
# gpart add -t freebsd-zfs -s 60g da0
# gpart add -t freebsd-swap da0
resulting in something like:
# gpart show
=>        0  143331930  da0  VTOC8  (68G)
          0  125821080    1  freebsd-zfs  (60G)
  125821080   17510850    2  freebsd-swap  (8.4G)

3. create zpool
# zpool create bunker da0a
or for mirror/RAIDZ (after preparing additional disks as in steps 1. + 2.):
# zpool create bunker mirror da0a da1a
# zpool create bunker raidz da0a da1a da2a ...

4. set bootfs
# zpool set bootfs=bunker bunker

5. install zfsboot
# zpool export bunker
# gpart bootcode -p /boot/zfsboot da0

6. write zfsloader to the ZFS Boot Block (so far, there's no dedicated tool
for this, so dd(1) has to be used for this purpose)
When using mirror/RAIDZ, step 4. and the dd(1) invocation should be repeated
for the additional disks in order to be able to boot from another disk in
case of failure.
# sysctl kern.geom.debugflags=0x10
# dd if=/boot/zfsloader of=/dev/da0a bs=512 oseek=1024 conv=notrunc
# zpool import bunker

7. install system on ZFS filesystem
Don't forget to set 'zfs_load="YES"' and vfs.root.mountfrom="zfs:bunker" in
loader.conf as well as 'zfs_enable="YES"'in rc.conf.

8. copy zpool.cache to the ZFS filesystem
cp -p /boot/zfs/zpool.cache /bunker/boot/zfs/zpool.cache

9. set mountpoint
# zfs set mountpoint=/ bunker

10. Now, given that aliases for all disks in the zpool exists (check with
the `devalias` command on the boot monitor prompt) and disk0 corresponds
to da0 (likewise for additional disks), the system can be booted from the
ZFS with:
{1} ok boot disk0

PR:             165025
Submitted by:   Gavin Mu

1 files changed, 19 insertions, 3 deletions

diff --git a/sys/boot/ofw/libofw/devicename.c b/sys/boot/ofw/libofw/devicename.c
index 3cae23c..c2d9ef1 100644
--- a/sys/boot/ofw/libofw/devicename.c
+++ b/sys/boot/ofw/libofw/devicename.c
@@ -28,6 +28,8 @@
 __FBSDID("$FreeBSD$");
 
 #include <stand.h>
+
+#include "bootstrap.h"
 #include "libofw.h"
 
 static int ofw_parsedev(struct ofw_devdesc **, const char *, const char **);
@@ -76,6 +78,7 @@ ofw_parsedev(struct ofw_devdesc **dev, const char *devspec, const char **path)
     phandle_t		handle;
     const char		*p;
     const char		*s;
+    char		*ep;
     char		name[256];
     char		type[64];
     int			len;
@@ -87,9 +90,10 @@ ofw_parsedev(struct ofw_devdesc **dev, const char *devspec, const char **path)
 	len = s - devspec;
 	bcopy(devspec, name, len);
 	name[len] = '\0';
-	if ((handle = OF_finddevice(name)) == -1)
-	    break;
-	if (OF_getprop(handle, "device_type", type, sizeof(type)) == -1)
+	if ((handle = OF_finddevice(name)) == -1) {
+	    bcopy(name, type, len);
+	    type[len] = '\0';
+	} else if (OF_getprop(handle, "device_type", type, sizeof(type)) == -1)
 	    continue;
 	for (i = 0; (dv = devsw[i]) != NULL; i++) {
 	    if (strncmp(dv->dv_name, type, strlen(dv->dv_name)) == 0)
@@ -109,6 +113,18 @@ found:
     strcpy(idev->d_path, name);
     idev->d_dev = dv;
     idev->d_type = dv->dv_type;
+    if (idev->d_type == DEVT_ZFS) {
+	idev->d_unit = 0;
+	p = name + strlen(dv->dv_name);
+	if (*p && (*p != ':')) {
+	    idev->d_unit = strtol(p, &ep, 0);
+	    if (ep == p) {
+		free(idev);
+		return (EUNIT);
+	    }
+	}
+    }
+
     if (dev == NULL) {
 	free(idev);
     } else {