[Qemu-devel] [PATCH] don't boot from un-selected devices

[Amos Kong <akong@redhat.com>]

Current seabios will try to boot from selected devices first,
if they are all failed, seabios will also try to boot from
un-selected devices.

For example:
@ qemu-kvm -boot order=n,menu=on ...

Guest will boot from network first, if it's failed, guest will try to
boot from other un-selected devices (floppy, cdrom, disk) one by one.

Sometimes, user don't want to boot from some devices. This patch changes
seabios to boot only from selected devices.

If user choose first boot device from menu, then seabios will try all
the devices, even some of them are not selected.

Signed-off-by: Amos Kong <akong@redhat.com>
---
 src/boot.c |   13 ++++++++-----
 1 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/boot.c b/src/boot.c
index 3ca7960..ee810ac 100644
--- a/src/boot.c
+++ b/src/boot.c
@@ -424,6 +424,10 @@ interactive_bootmenu(void)
         maxmenu++;
         printf("%d. %s\n", maxmenu
                , strtcpy(desc, pos->description, ARRAY_SIZE(desc)));
+        /* If user chooses first boot device from menu, we will treat
+	    all the devices as selected. */
+        if (pos->priority == DEFAULT_PRIO)
+            pos->priority = DEFAULT_PRIO - 1;
         pos = pos->next;
     }
 
@@ -490,7 +494,10 @@ boot_prep(void)
 
     // Map drives and populate BEV list
     struct bootentry_s *pos = BootList;
-    while (pos) {
+
+    /* The priority of un-selected device is not changed,
+       we only boot from user selected devices. */
+    while (pos && pos->priority != DEFAULT_PRIO) {
         switch (pos->type) {
         case IPL_TYPE_BCV:
             call_bcv(pos->vector.seg, pos->vector.offset);
@@ -513,10 +520,6 @@ boot_prep(void)
         }
         pos = pos->next;
     }
-
-    // If nothing added a floppy/hd boot - add it manually.
-    add_bev(IPL_TYPE_FLOPPY, 0);
-    add_bev(IPL_TYPE_HARDDISK, 0);
 }
 
 
-- 
1.7.1