dracut: initialize volatile.img partitions

Do not rely on dom0 initializing that device. Actually volatile.img
content should be none of dom0 business.

QubesOS/qubes-issues#1308

dracut/full/module-setup.sh

@@ -11,5 +11,7 @@ check() {
 install() {
     inst_hook pre-udev 90 $moddir/qubes_cow_setup.sh
     inst_hook pre-pivot 50 $moddir/mount_modules.sh
-
+    inst_multiple \
+        sfdisk \
+        mkswap
 }

dracut/full/qubes_cow_setup.sh

@@ -18,6 +18,22 @@ if [ `cat /sys/block/xvda/ro` = 1 ] ; then
     echo "Qubes: Doing COW setup for AppVM..."
 
     while ! [ -e /dev/xvdc ]; do sleep 0.1; done
+    VOLATILE_SIZE=$(sfdisk -s /dev/xvdc)
+    ROOT_SIZE=$(sfdisk -s /dev/xvda) # kbytes
+    SWAP_SIZE=1024 # kbytes
+    if [ $VOLATILE_SIZE -lt $(($ROOT_SIZE + $SWAP_SIZE)) ]; then
+        ROOT_SIZE=$(($VOLATILE_SIZE - $SWAP_SIZE))
+    fi
+    sfdisk -q --unit B /dev/xvdc >/dev/null <<EOF
+0,$SWAP_SIZE,S
+,$ROOT_SIZE,L
+EOF
+    if [ $? -ne 0 ]; then
+        echo "Qubes: failed to setup partitions on volatile device"
+        exit 1
+    fi
+    while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
+    mkswap /dev/xvdc1
     while ! [ -e /dev/xvdc2 ]; do sleep 0.1; done
 
     echo "0 `cat /sys/block/xvda/size` snapshot /dev/xvda /dev/xvdc2 N 16" | \

dracut/simple/init.sh

@@ -19,6 +19,22 @@ if [ `cat /sys/block/xvda/ro` = 1 ] ; then
     echo "Qubes: Doing COW setup for AppVM..."
 
     while ! [ -e /dev/xvdc ]; do sleep 0.1; done
+    VOLATILE_SIZE=$(sfdisk -s /dev/xvdc)
+    ROOT_SIZE=$(sfdisk -s /dev/xvda) # kbytes
+    SWAP_SIZE=1024 # kbytes
+    if [ $VOLATILE_SIZE -lt $(($ROOT_SIZE + $SWAP_SIZE)) ]; then
+        ROOT_SIZE=$(($VOLATILE_SIZE - $SWAP_SIZE))
+    fi
+    sfdisk -q --unit B /dev/xvdc >/dev/null <<EOF
+0,$SWAP_SIZE,S
+,$ROOT_SIZE,L
+EOF
+    if [ $? -ne 0 ]; then
+        echo "Qubes: failed to setup partitions on volatile device"
+        exit 1
+    fi
+    while ! [ -e /dev/xvdc1 ]; do sleep 0.1; done
+    mkswap /dev/xvdc1
     while ! [ -e /dev/xvdc2 ]; do sleep 0.1; done
 
     echo "0 `cat /sys/block/xvda/size` snapshot /dev/xvda /dev/xvdc2 N 16" | \

dracut/simple/module-setup.sh

@@ -11,4 +11,7 @@ depends() {
 
 install() {
     inst $moddir/init.sh /init
+    inst_multiple \
+        sfdisk \
+        mkswap
 }

kernel-modules/u2mfn/u2mfn.c

@@ -80,7 +80,7 @@ static long u2mfn_ioctl(struct file *f, unsigned int cmd,
 		    (current, current->mm, data, 1, 1, 0, &user_page, 0);
 		up_read(&current->mm->mmap_sem);
 		if (ret != 1) {
-			printk("U2MFN_GET_MFN_FOR_PAGE: get_user_pages failed, ret=0x%x\n", ret);
+			printk("U2MFN_GET_MFN_FOR_PAGE: get_user_pages failed, ret=0x%lx\n", ret);
 			return -1;
 		}
 		kaddr = kmap(user_page);