This patch to pc-sysinstall allows the setting of a new config

variable for installation, which lets the user/front-end select
between MBR or GPT partitioning schemes when doing a dedicated disk
installation.

PR:		149772
Submitted by:	Kris Moore

usr.sbin/pc-sysinstall/backend/functions-disk.sh

@@ -406,6 +406,18 @@ setup_disk_slice()
        fi
      fi
 
+     # Check if we have a partscheme specified
+     echo $line | grep "^partscheme=" >/dev/null 2>/dev/null
+     if [ "$?" = "0" ] ; then
+       # Found a partscheme= entry, lets read / set it 
+       get_value_from_string "${line}"
+       strip_white_space "$VAL"
+       PSCHEME="$VAL"
+       if [ "$PSCHEME" != "GPT" -a "$PSCHEME" != "MBR" ] ; then
+	 exit_err "Unknown partition scheme: $PSCHEME" 
+       fi
+     fi
+
      echo $line | grep "^bootManager=" >/dev/null 2>/dev/null
      if [ "$?" = "0" ]
      then
@@ -422,8 +434,13 @@ setup_disk_slice()
        if [ ! -z "${DISK}" -a ! -z "${PTYPE}" ]
        then
          case ${PTYPE} in
-                   all|ALL) tmpSLICE="${DISK}p1"  
-                        run_gpart_full "${DISK}" "${BMANAGER}" ;;
+               all|ALL) if [ "$PSCHEME" = "MBR" -o -z "$PSCHEME" ] ; then
+			  PSCHEME="MBR"
+			  tmpSLICE="${DISK}s1"  
+			else
+			  tmpSLICE="${DISK}p1"  
+			fi
+                        run_gpart_full "${DISK}" "${BMANAGER}" "${PSCHEME}" ;;
            s1|s2|s3|s4) tmpSLICE="${DISK}${PTYPE}" 
                         # Get the number of the slice we are working on
                         s="`echo ${PTYPE} | awk '{print substr($0,length,1)}'`" 
@@ -449,7 +466,7 @@ setup_disk_slice()
 
 
          # Increment our disk counter to look for next disk and unset
-         unset BMANAGER PTYPE DISK MIRRORDISK MIRRORBAL
+         unset BMANAGER PTYPE DISK MIRRORDISK MIRRORBAL PSCHEME
          disknum="`expr $disknum + 1`"
        else
          exit_err "ERROR: commitDiskPart was called without procceding disk<num>= and partition= entries!!!" 
@@ -477,7 +494,7 @@ stop_gjournal() {
   fi
 } ;
 
-# Function which runs gpart and creates a single large slice
+# Function which runs gpart and creates a single large GPT partition scheme
 init_gpt_full_disk()
 {
   _intDISK=$1
@@ -506,14 +523,82 @@ init_gpt_full_disk()
 
 }
 
+# Function which runs gpart and creates a single large MBR partition scheme
+init_mbr_full_disk()
+{
+  _intDISK=$1
+  _intBOOT=$2
+ 
+  startblock="63"
+
+  # Set our sysctl so we can overwrite any geom using drives
+  sysctl kern.geom.debugflags=16 >>${LOGOUT} 2>>${LOGOUT}
+
+  # Stop any journaling
+  stop_gjournal "${_intDISK}"
+
+  # Remove any existing partitions
+  delete_all_gpart "${_intDISK}"
+
+  #Erase any existing bootloader
+  echo_log "Cleaning up ${_intDISK}"
+  rc_halt "dd if=/dev/zero of=/dev/${_intDISK} count=2048"
+
+  sleep 2
+
+  echo_log "Running gpart on ${_intDISK}"
+  rc_halt "gpart create -s mbr ${_intDISK}"
+
+  # Lets figure out disk size in blocks
+  # Get the cyl of this disk
+  get_disk_cyl "${_intDISK}"
+  cyl="${VAL}"
+
+  # Get the heads of this disk
+  get_disk_heads "${_intDISK}"
+  head="${VAL}"
+
+  # Get the tracks/sectors of this disk
+  get_disk_sectors "${_intDISK}"
+  sec="${VAL}"
+
+  # Multiply them all together to get our total blocks
+  totalblocks="`expr ${cyl} \* ${head}`"
+  totalblocks="`expr ${totalblocks} \* ${sec}`"
+
+
+  # Now set the ending block to the total disk block size
+  sizeblock="`expr ${totalblocks} - ${startblock}`"
+
+  # Install new partition setup
+  echo_log "Running gpart add on ${_intDISK}"
+  rc_halt "gpart add -b ${startblock} -s ${sizeblock} -t freebsd -i 1 ${_intDISK}"
+  sleep 2
+  
+  echo_log "Cleaning up ${_intDISK}s1"
+  rc_halt "dd if=/dev/zero of=/dev/${_intDISK}s1 count=1024"
+  
+  if [ "$_intBOOT" = "bsd" ] ; then
+    echo_log "Stamping boot sector on ${_intDISK}"
+    rc_halt "gpart bootcode -b /boot/boot0 ${_intDISK}"
+  fi
+
+}
+
 # Function which runs gpart and creates a single large slice
 run_gpart_full()
 {
   DISK=$1
+  BOOT=$2
+  SCHEME=$3
 
-  init_gpt_full_disk "$DISK"
-
-  slice="${DISK}-1-gpt"
+  if [ "$SCHEME" = "MBR" ] ; then
+    init_mbr_full_disk "$DISK" "$BOOT"
+    slice="${DISK}-1-mbr"
+  else
+    init_gpt_full_disk "$DISK"
+    slice="${DISK}-1-gpt"
+  fi
 
   # Lets save our slice, so we know what to look for in the config file later on
   if [ -z "$WORKINGSLICES" ]

usr.sbin/pc-sysinstall/examples/README

@@ -128,6 +128,11 @@ Setting this to "s1, s2, s3 or s4" will use the specified MBR slice
 
 (This tag is unused for upgrades)
 
+# partscheme=(MBR/GPT)
+
+When performing a "full" disk (partition=all), the partscheme= variable is used
+to determine the partition scheme type gpart will be using on the disk. Valid
+choices are MBR or GPT. 
 
 # mirror=(disk device such as ad1)