[src/trunk]: src/sys/dev/raidframe restore defaulting to the 'a' partition fo...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a42912ac3e89
branches:  trunk
changeset: 329165:a42912ac3e89
user:      christos <christos%NetBSD.org@localhost>
date:      Mon May 12 15:53:01 2014 +0000

description:
restore defaulting to the 'a' partition for booting with root on raid as
it was before, and explain why we do things this way.

diffstat:

 sys/dev/raidframe/rf_netbsdkintf.c |  22 ++++++++++++++++++----
 1 files changed, 18 insertions(+), 4 deletions(-)

diffs (62 lines):

diff -r 5c739eaf5bc5 -r a42912ac3e89 sys/dev/raidframe/rf_netbsdkintf.c
--- a/sys/dev/raidframe/rf_netbsdkintf.c        Mon May 12 15:34:23 2014 +0000
+++ b/sys/dev/raidframe/rf_netbsdkintf.c        Mon May 12 15:53:01 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rf_netbsdkintf.c,v 1.309 2014/05/08 20:36:15 jakllsch Exp $    */
+/*     $NetBSD: rf_netbsdkintf.c,v 1.310 2014/05/12 15:53:01 christos Exp $    */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 2008-2011 The NetBSD Foundation, Inc.
@@ -101,7 +101,7 @@
  ***********************************************************/
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rf_netbsdkintf.c,v 1.309 2014/05/08 20:36:15 jakllsch Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rf_netbsdkintf.c,v 1.310 2014/05/12 15:53:01 christos Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_compat_netbsd.h"
@@ -527,11 +527,22 @@
 
        /* we found something bootable... */
 
+       /*
+        * XXX: The following code assumes that the root raid
+        * is the first ('a') partition. This is about the best
+        * we can do with a BSD disklabel, but we might be able
+        * to do better with a GPT label, by setting a specified
+        * attribute to indicate the root partition. We can then
+        * stash the partition number in the r->root_partition
+        * high bits (the bottom 2 bits are already used). For
+        * now we just set booted_partition to 0 when we override
+        * root.
+        */
        if (num_root == 1) {
                device_t candidate_root;
                if (rsc->sc_dkdev.dk_nwedges != 0) {
-                       /* XXX: How do we find the real root partition? */
                        char cname[sizeof(cset->ac->devname)];
+                       /* XXX: assume 'a' */
                        snprintf(cname, sizeof(cname), "%s%c",
                            device_xname(rsc->sc_dev), 'a');
                        candidate_root = dkwedge_find_by_wname(cname);
@@ -539,8 +550,10 @@
                        candidate_root = rsc->sc_dev;
                if (booted_device == NULL ||
                    rsc->sc_r.root_partition == 1 ||
-                   rf_containsboot(&rsc->sc_r, booted_device))
+                   rf_containsboot(&rsc->sc_r, booted_device)) {
                        booted_device = candidate_root;
+                       booted_partition = 0;   /* XXX assume 'a' */
+               }
        } else if (num_root > 1) {
 
                /* 
@@ -571,6 +584,7 @@
 
                if (num_root == 1) {
                        booted_device = rsc->sc_dev;
+                       booted_partition = 0;   /* XXX assume 'a' */
                } else {
                        /* we can't guess.. require the user to answer... */
                        boothowto |= RB_ASKNAME;