Pull the tier-2 card and change the sparc64 ZFS loader to no longer probe

all diskN aliases for providers (which more or less corresponds to how the
x86 version behaves) but instead probe only those listed in the boot-device
OFW environment variable. This has the following advantages:
- avoids otherwise unavoidable OFW warnings about failures to open disks
  for which aliases exist but no actual hardware is connected
- avoids issues due to different diskN naming schemes
- aligns us with Solaris

MFC after:	3 days

1 files changed, 43 insertions, 9 deletions

diff --git a/sys/boot/sparc64/loader/main.c b/sys/boot/sparc64/loader/main.c
index 4cbea17..9b76f0d 100644
--- a/sys/boot/sparc64/loader/main.c
+++ b/sys/boot/sparc64/loader/main.c
@@ -7,7 +7,7 @@
  * unchanged, you can do what ever you want with this file.
  */
 /*-
- * Copyright (c) 2008 Marius Strobl <marius@FreeBSD.org>
+ * Copyright (c) 2008 - 2012 Marius Strobl <marius@FreeBSD.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -75,8 +75,6 @@ __FBSDID("$FreeBSD$");
 #include "libofw.h"
 #include "dev_net.h"
 
-#define	MAXDEV	31
-
 extern char bootprog_name[], bootprog_rev[], bootprog_date[], bootprog_maker[];
 
 enum {
@@ -735,18 +733,52 @@ sparc64_zfs_probe(void)
 {
 	struct vtoc8 vtoc;
 	struct zfs_devdesc zfs_currdev;
-	char devname[32];
+	char alias[64], devname[sizeof(alias) + sizeof(":x") - 1];
+	char type[sizeof("device_type")];
+	char *bdev, *dev, *odev;
 	uint64_t guid;
-	int fd, part, unit;
+	int fd, len, part;
+	phandle_t aliases, options;
 
 	/* Get the GUID of the ZFS pool on the boot device. */
 	guid = 0;
 	zfs_probe_dev(bootpath, &guid);
 
-	for (unit = 0; unit < MAXDEV; unit++) {
+	/*
+	 * Get the GUIDs of the ZFS pools on any additional disks listed in
+	 * the boot-device environment variable.
+	 */
+	if ((aliases = OF_finddevice("/aliases")) == -1)
+		goto out;
+	options = OF_finddevice("/options");
+	len = OF_getproplen(options, "boot-device");
+	if (len <= 0)
+		goto out;
+	bdev = odev = malloc(len + 1);
+	if (bdev == NULL)
+		goto out;
+	if (OF_getprop(options, "boot-device", bdev, len) <= 0)
+		goto out;
+	bdev[len] = '\0';
+	while ((dev = strsep(&bdev, " ")) != NULL) {
+		if (*dev == '\0')
+			continue;
+		strcpy(alias, dev);
+		(void)OF_getprop(aliases, dev, alias, sizeof(alias));
+		/*
+		 * Don't probe the boot disk twice.  Note that bootpath
+		 * includes the partition specifier.
+		 */
+		if (strncmp(alias, bootpath, strlen(alias)) == 0)
+			continue;
+		if (OF_getprop(OF_finddevice(alias), "device_type", type,
+		    sizeof(type)) == -1)
+			continue;
+		if (strcmp(type, "block") != 0)
+			continue;
+
 		/* Find freebsd-zfs slices in the VTOC. */
-		sprintf(devname, "disk%d:", unit);
-		fd = open(devname, O_RDONLY);
+		fd = open(alias, O_RDONLY);
 		if (fd == -1)
 			continue;
 		lseek(fd, 0, SEEK_SET);
@@ -760,12 +792,14 @@ sparc64_zfs_probe(void)
 			if (part == 2 || vtoc.part[part].tag !=
 			    VTOC_TAG_FREEBSD_ZFS)
 				continue;
-			sprintf(devname, "disk%d:%c", unit, part + 'a');
+			(void)sprintf(devname, "%s:%c", alias, part + 'a');
 			if (zfs_probe_dev(devname, NULL) == ENXIO)
 				break;
 		}
 	}
+	free(odev);
 
+ out:
 	if (guid != 0) {
 		zfs_currdev.pool_guid = guid;
 		zfs_currdev.root_guid = 0;