Add KVM support to QEMU

This patch adds very basic KVM support.  KVM is a kernel module for Linux that
allows userspace programs to make use of hardware virtualization support.  It
current supports x86 hardware virtualization using Intel VT-x or AMD-V.  It
also supports IA64 VT-i, PPC 440, and S390.

This patch only implements the bare minimum support to get a guest booting.  It
has very little impact the rest of QEMU and attempts to integrate nicely with
the rest of QEMU.

Even though this implementation is basic, it is significantly faster than TCG.
Booting and shutting down a Linux guest:

w/TCG:  1:32.36 elapsed  84% CPU

w/KVM:  0:31.14 elapsed  59% CPU

Right now, KVM is disabled by default and must be explicitly enabled with
 -enable-kvm.  We can enable it by default later when we have had better
testing.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5627 c046a42c-6fe2-441c-8c8c-71466251a162

1 files changed, 48 insertions, 0 deletions

diff --git a/configure b/configure
index 8b0ad89b12..53167d5df7 100755
--- a/configure
+++ b/configure
@@ -115,6 +115,7 @@ aio="yes"
 nptl="yes"
 mixemu="no"
 bluez="yes"
+kvm="yes"
 
 # OS specific
 targetos=`uname -s`
@@ -303,6 +304,8 @@ for opt do
   ;;
   --disable-bluez) bluez="no"
   ;;
+  --disable-kvm) kvm="no"
+  ;;
   --enable-profiler) profiler="yes"
   ;;
   --enable-cocoa)
@@ -448,6 +451,7 @@ echo "  --disable-brlapi         disable BrlAPI"
 echo "  --disable-vnc-tls        disable TLS encryption for VNC server"
 echo "  --disable-curses         disable curses output"
 echo "  --disable-bluez          disable bluez stack connectivity"
+echo "  --disable-kvm            disable KVM acceleration support"
 echo "  --disable-nptl           disable usermode NPTL support"
 echo "  --enable-system          enable all system emulation targets"
 echo "  --disable-system         disable all system emulation targets"
@@ -951,6 +955,30 @@ EOF
 fi
 
 ##########################################
+# kvm probe
+if test "$kvm" = "yes" ; then
+    cat > $TMPC <<EOF
+#include <linux/kvm.h>
+#if !defined(KVM_API_VERSION) || \
+    KVM_API_VERSION < 12 || \
+    KVM_API_VERSION > 12 || \
+    !defined(KVM_CAP_USER_MEMORY) || \
+    !defined(KVM_CAP_SET_TSS_ADDR)
+#error Invalid KVM version
+#endif
+int main(void) { return 0; }
+EOF
+  # FIXME make this configurable
+  kvm_cflags=-I/lib/modules/`uname -r`/build/include
+  if $cc $ARCH_CFLAGS -o $TMPE ${OS_CFLAGS} $kvm_cflags $TMPC \
+      2>/dev/null ; then
+    :
+  else
+    kvm="no"
+  fi
+fi
+
+##########################################
 # AIO probe
 if test "$aio" = "yes" ; then
   aio=no
@@ -1036,6 +1064,7 @@ echo "uname -r          $uname_release"
 echo "NPTL support      $nptl"
 echo "vde support       $vde"
 echo "AIO support       $aio"
+echo "KVM support       $kvm"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1411,6 +1440,15 @@ interp_prefix1=`echo "$interp_prefix" | sed "s/%M/$target_cpu/g"`
 echo "#define CONFIG_QEMU_PREFIX \"$interp_prefix1\"" >> $config_h
 gdb_xml_files=""
 
+# FIXME allow i386 to build on x86_64 and vice versa
+if test "$kvm" = "yes" -a "$target_cpu" != "$cpu" ; then
+  kvm="no"
+fi
+# Disable KVM for linux-user
+if test "$kvm" = "yes" -a "$target_softmmu" = "no" ; then
+  kvm="no"
+fi
+
 case "$target_cpu" in
   i386)
     echo "TARGET_ARCH=i386" >> $config_mak
@@ -1420,6 +1458,11 @@ case "$target_cpu" in
     then
       echo "#define USE_KQEMU 1" >> $config_h
     fi
+    if test "$kvm" = "yes" ; then
+      echo "CONFIG_KVM=yes" >> $config_mak
+      echo "KVM_CFLAGS=$kvm_cflags" >> $config_mak
+      echo "#define CONFIG_KVM" >> $config_h
+    fi
     gcc3minver=`$cc --version 2> /dev/null| fgrep "(GCC) 3." | awk '{ print $3 }' | cut -f2 -d.`
     if test -n "$gcc3minver" && test $gcc3minver -gt 3
     then
@@ -1437,6 +1480,11 @@ case "$target_cpu" in
     then
       echo "#define USE_KQEMU 1" >> $config_h
     fi
+    if test "$kvm" = "yes" ; then
+      echo "CONFIG_KVM=yes" >> $config_mak
+      echo "KVM_CFLAGS=$kvm_cflags" >> $config_mak
+      echo "#define CONFIG_KVM 1" >> $config_h
+    fi
   ;;
   alpha)
     echo "TARGET_ARCH=alpha" >> $config_mak