diff --git a/configure b/configure
index 677afd646..18e41eca4 100755
--- a/configure
+++ b/configure
@@ -30,6 +30,8 @@ ac_help="$ac_help
   --enable-debug          Enable debugging"
 ac_help="$ac_help
   --disable-devmapper     Disable device-mapper interaction"
+ac_help="$ac_help
+  --disable-o_direct      Disable O_DIRECT"
 
 # Initialize some variables set by options.
 # The variables have the same names as the options, with
@@ -561,12 +563,12 @@ ac_config_sub=$ac_aux_dir/config.sub
 ac_configure=$ac_aux_dir/configure # This should be Cygnus configure.
  
 
-for ac_prog in mawk gawk nawk awk
+for ac_prog in gawk mawk nawk awk
 do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:570: checking for $ac_word" >&5
+echo "configure:572: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_AWK'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -598,7 +600,7 @@ done
 # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:602: checking for $ac_word" >&5
+echo "configure:604: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -628,7 +630,7 @@ if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:632: checking for $ac_word" >&5
+echo "configure:634: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -679,7 +681,7 @@ fi
       # Extract the first word of "cl", so it can be a program name with args.
 set dummy cl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:683: checking for $ac_word" >&5
+echo "configure:685: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -711,7 +713,7 @@ fi
 fi
 
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works""... $ac_c" 1>&6
-echo "configure:715: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
+echo "configure:717: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
 
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
@@ -722,12 +724,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 
 cat > conftest.$ac_ext << EOF
 
-#line 726 "configure"
+#line 728 "configure"
 #include "confdefs.h"
 
 main(){return(0);}
 EOF
-if { (eval echo configure:731: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:733: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   ac_cv_prog_cc_works=yes
   # If we can't run a trivial program, we are probably using a cross compiler.
   if (./conftest; exit) 2>/dev/null; then
@@ -753,12 +755,12 @@ if test $ac_cv_prog_cc_works = no; then
   { echo "configure: error: installation or configuration problem: C compiler cannot create executables." 1>&2; exit 1; }
 fi
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler""... $ac_c" 1>&6
-echo "configure:757: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
+echo "configure:759: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
 echo "$ac_t""$ac_cv_prog_cc_cross" 1>&6
 cross_compiling=$ac_cv_prog_cc_cross
 
 echo $ac_n "checking whether we are using GNU C""... $ac_c" 1>&6
-echo "configure:762: checking whether we are using GNU C" >&5
+echo "configure:764: checking whether we are using GNU C" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -767,7 +769,7 @@ else
   yes;
 #endif
 EOF
-if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:771: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
+if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:773: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
   ac_cv_prog_gcc=yes
 else
   ac_cv_prog_gcc=no
@@ -786,7 +788,7 @@ ac_test_CFLAGS="${CFLAGS+set}"
 ac_save_CFLAGS="$CFLAGS"
 CFLAGS=
 echo $ac_n "checking whether ${CC-cc} accepts -g""... $ac_c" 1>&6
-echo "configure:790: checking whether ${CC-cc} accepts -g" >&5
+echo "configure:792: checking whether ${CC-cc} accepts -g" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_cc_g'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -829,7 +831,7 @@ fi
 # SVR4 /usr/ucb/install, which tries to use the nonexistent group "staff"
 # ./install, which can be erroneously created by make from ./install.sh.
 echo $ac_n "checking for a BSD compatible install""... $ac_c" 1>&6
-echo "configure:833: checking for a BSD compatible install" >&5
+echo "configure:835: checking for a BSD compatible install" >&5
 if test -z "$INSTALL"; then
 if eval "test \"`echo '$''{'ac_cv_path_install'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -882,7 +884,7 @@ test -z "$INSTALL_SCRIPT" && INSTALL_SCRIPT='${INSTALL_PROGRAM}'
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
 echo $ac_n "checking whether ln -s works""... $ac_c" 1>&6
-echo "configure:886: checking whether ln -s works" >&5
+echo "configure:888: checking whether ln -s works" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_LN_S'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -903,7 +905,7 @@ else
 fi
 
 echo $ac_n "checking whether ${MAKE-make} sets \${MAKE}""... $ac_c" 1>&6
-echo "configure:907: checking whether ${MAKE-make} sets \${MAKE}" >&5
+echo "configure:909: checking whether ${MAKE-make} sets \${MAKE}" >&5
 set dummy ${MAKE-make}; ac_make=`echo "$2" | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_prog_make_${ac_make}_set'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -932,7 +934,7 @@ fi
 # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:936: checking for $ac_word" >&5
+echo "configure:938: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -965,12 +967,12 @@ for ac_hdr in dirent.h sys/ndir.h sys/dir.h ndir.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr that defines DIR""... $ac_c" 1>&6
-echo "configure:969: checking for $ac_hdr that defines DIR" >&5
+echo "configure:971: checking for $ac_hdr that defines DIR" >&5
 if eval "test \"`echo '$''{'ac_cv_header_dirent_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 974 "configure"
+#line 976 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <$ac_hdr>
@@ -978,7 +980,7 @@ int main() {
 DIR *dirp = 0;
 ; return 0; }
 EOF
-if { (eval echo configure:982: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:984: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   eval "ac_cv_header_dirent_$ac_safe=yes"
 else
@@ -1003,7 +1005,7 @@ done
 # Two versions of opendir et al. are in -ldir and -lx on SCO Xenix.
 if test $ac_header_dirent = dirent.h; then
 echo $ac_n "checking for opendir in -ldir""... $ac_c" 1>&6
-echo "configure:1007: checking for opendir in -ldir" >&5
+echo "configure:1009: checking for opendir in -ldir" >&5
 ac_lib_var=`echo dir'_'opendir | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1011,7 +1013,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-ldir  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1015 "configure"
+#line 1017 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1022,7 +1024,7 @@ int main() {
 opendir()
 ; return 0; }
 EOF
-if { (eval echo configure:1026: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1028: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -1044,7 +1046,7 @@ fi
 
 else
 echo $ac_n "checking for opendir in -lx""... $ac_c" 1>&6
-echo "configure:1048: checking for opendir in -lx" >&5
+echo "configure:1050: checking for opendir in -lx" >&5
 ac_lib_var=`echo x'_'opendir | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1052,7 +1054,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lx  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1056 "configure"
+#line 1058 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1063,7 +1065,7 @@ int main() {
 opendir()
 ; return 0; }
 EOF
-if { (eval echo configure:1067: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1069: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -1086,7 +1088,7 @@ fi
 fi
 
 echo $ac_n "checking how to run the C preprocessor""... $ac_c" 1>&6
-echo "configure:1090: checking how to run the C preprocessor" >&5
+echo "configure:1092: checking how to run the C preprocessor" >&5
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
@@ -1101,13 +1103,13 @@ else
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp.
   cat > conftest.$ac_ext <<EOF
-#line 1105 "configure"
+#line 1107 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1111: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1113: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1118,13 +1120,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -E -traditional-cpp"
   cat > conftest.$ac_ext <<EOF
-#line 1122 "configure"
+#line 1124 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1128: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1130: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1135,13 +1137,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -nologo -E"
   cat > conftest.$ac_ext <<EOF
-#line 1139 "configure"
+#line 1141 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1145: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1147: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1166,12 +1168,12 @@ fi
 echo "$ac_t""$CPP" 1>&6
 
 echo $ac_n "checking for ANSI C header files""... $ac_c" 1>&6
-echo "configure:1170: checking for ANSI C header files" >&5
+echo "configure:1172: checking for ANSI C header files" >&5
 if eval "test \"`echo '$''{'ac_cv_header_stdc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1175 "configure"
+#line 1177 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 #include <stdarg.h>
@@ -1179,7 +1181,7 @@ else
 #include <float.h>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1183: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1185: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1196,7 +1198,7 @@ rm -f conftest*
 if test $ac_cv_header_stdc = yes; then
   # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
 cat > conftest.$ac_ext <<EOF
-#line 1200 "configure"
+#line 1202 "configure"
 #include "confdefs.h"
 #include <string.h>
 EOF
@@ -1214,7 +1216,7 @@ fi
 if test $ac_cv_header_stdc = yes; then
   # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
 cat > conftest.$ac_ext <<EOF
-#line 1218 "configure"
+#line 1220 "configure"
 #include "confdefs.h"
 #include <stdlib.h>
 EOF
@@ -1235,7 +1237,7 @@ if test "$cross_compiling" = yes; then
   :
 else
   cat > conftest.$ac_ext <<EOF
-#line 1239 "configure"
+#line 1241 "configure"
 #include "confdefs.h"
 #include <ctype.h>
 #define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
@@ -1246,7 +1248,7 @@ if (XOR (islower (i), ISLOWER (i)) || toupper (i) != TOUPPER (i)) exit(2);
 exit (0); }
 
 EOF
-if { (eval echo configure:1250: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
+if { (eval echo configure:1252: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext} && (./conftest; exit) 2>/dev/null
 then
   :
 else
@@ -1273,17 +1275,17 @@ for ac_hdr in fcntl.h malloc.h sys/ioctl.h unistd.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1277: checking for $ac_hdr" >&5
+echo "configure:1279: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1282 "configure"
+#line 1284 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1287: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1289: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1311,18 +1313,18 @@ done
 
 
 echo $ac_n "checking for working const""... $ac_c" 1>&6
-echo "configure:1315: checking for working const" >&5
+echo "configure:1317: checking for working const" >&5
 if eval "test \"`echo '$''{'ac_cv_c_const'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1320 "configure"
+#line 1322 "configure"
 #include "confdefs.h"
 
 int main() {
 
 /* Ultrix mips cc rejects this.  */
-typedef int charset[2]; const charset x = {0,0};
+typedef int charset[2]; const charset x;
 /* SunOS 4.1.1 cc rejects this.  */
 char const *const *ccp;
 char **p;
@@ -1365,7 +1367,7 @@ ccp = (char const *const *) p;
 
 ; return 0; }
 EOF
-if { (eval echo configure:1369: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1371: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_c_const=yes
 else
@@ -1386,21 +1388,21 @@ EOF
 fi
 
 echo $ac_n "checking for inline""... $ac_c" 1>&6
-echo "configure:1390: checking for inline" >&5
+echo "configure:1392: checking for inline" >&5
 if eval "test \"`echo '$''{'ac_cv_c_inline'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_cv_c_inline=no
 for ac_kw in inline __inline__ __inline; do
   cat > conftest.$ac_ext <<EOF
-#line 1397 "configure"
+#line 1399 "configure"
 #include "confdefs.h"
 
 int main() {
-} int $ac_kw foo() {
+} $ac_kw foo() {
 ; return 0; }
 EOF
-if { (eval echo configure:1404: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1406: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_c_inline=$ac_kw; break
 else
@@ -1426,12 +1428,12 @@ EOF
 esac
 
 echo $ac_n "checking for off_t""... $ac_c" 1>&6
-echo "configure:1430: checking for off_t" >&5
+echo "configure:1432: checking for off_t" >&5
 if eval "test \"`echo '$''{'ac_cv_type_off_t'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1435 "configure"
+#line 1437 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #if STDC_HEADERS
@@ -1459,12 +1461,12 @@ EOF
 fi
 
 echo $ac_n "checking for pid_t""... $ac_c" 1>&6
-echo "configure:1463: checking for pid_t" >&5
+echo "configure:1465: checking for pid_t" >&5
 if eval "test \"`echo '$''{'ac_cv_type_pid_t'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1468 "configure"
+#line 1470 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #if STDC_HEADERS
@@ -1492,12 +1494,12 @@ EOF
 fi
 
 echo $ac_n "checking for size_t""... $ac_c" 1>&6
-echo "configure:1496: checking for size_t" >&5
+echo "configure:1498: checking for size_t" >&5
 if eval "test \"`echo '$''{'ac_cv_type_size_t'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1501 "configure"
+#line 1503 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #if STDC_HEADERS
@@ -1525,12 +1527,12 @@ EOF
 fi
 
 echo $ac_n "checking for st_rdev in struct stat""... $ac_c" 1>&6
-echo "configure:1529: checking for st_rdev in struct stat" >&5
+echo "configure:1531: checking for st_rdev in struct stat" >&5
 if eval "test \"`echo '$''{'ac_cv_struct_st_rdev'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1534 "configure"
+#line 1536 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -1538,7 +1540,7 @@ int main() {
 struct stat s; s.st_rdev;
 ; return 0; }
 EOF
-if { (eval echo configure:1542: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1544: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_struct_st_rdev=yes
 else
@@ -1559,12 +1561,12 @@ EOF
 fi
 
 echo $ac_n "checking whether time.h and sys/time.h may both be included""... $ac_c" 1>&6
-echo "configure:1563: checking whether time.h and sys/time.h may both be included" >&5
+echo "configure:1565: checking whether time.h and sys/time.h may both be included" >&5
 if eval "test \"`echo '$''{'ac_cv_header_time'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1568 "configure"
+#line 1570 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <sys/time.h>
@@ -1573,7 +1575,7 @@ int main() {
 struct tm *tp;
 ; return 0; }
 EOF
-if { (eval echo configure:1577: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1579: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_header_time=yes
 else
@@ -1622,7 +1624,7 @@ else { echo "configure: error: can not run $ac_config_sub" 1>&2; exit 1; }
 fi
 
 echo $ac_n "checking host system type""... $ac_c" 1>&6
-echo "configure:1626: checking host system type" >&5
+echo "configure:1628: checking host system type" >&5
 
 host_alias=$host
 case "$host_alias" in
@@ -1643,7 +1645,7 @@ host_os=`echo $host | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\3/'`
 echo "$ac_t""$host" 1>&6
 
 echo $ac_n "checking target system type""... $ac_c" 1>&6
-echo "configure:1647: checking target system type" >&5
+echo "configure:1649: checking target system type" >&5
 
 target_alias=$target
 case "$target_alias" in
@@ -1661,7 +1663,7 @@ target_os=`echo $target | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\3/'`
 echo "$ac_t""$target" 1>&6
 
 echo $ac_n "checking build system type""... $ac_c" 1>&6
-echo "configure:1665: checking build system type" >&5
+echo "configure:1667: checking build system type" >&5
 
 build_alias=$build
 case "$build_alias" in
@@ -1784,19 +1786,33 @@ if test x$DEVMAPPER = xyes; then
 	CFLAGS="$CFLAGS -DDEVMAPPER_SUPPORT"
 fi
 
+# Check whether --enable-o_direct or --disable-o_direct was given.
+if test "${enable_o_direct+set}" = set; then
+  enableval="$enable_o_direct"
+  \
+ODIRECT=no
+else
+  ODIRECT=yes
+fi
+
+
+if test x$ODIRECT = xyes; then
+	CFLAGS="$CFLAGS -DO_DIRECT_SUPPORT"
+fi
+
 if [ "x$exec_prefix" = xNONE -a "x$prefix" = xNONE ];
  then  exec_prefix="";
 fi;
 
 if test $ac_cv_prog_gcc = yes; then
     echo $ac_n "checking whether ${CC-cc} needs -traditional""... $ac_c" 1>&6
-echo "configure:1794: checking whether ${CC-cc} needs -traditional" >&5
+echo "configure:1810: checking whether ${CC-cc} needs -traditional" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc_traditional'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
     ac_pattern="Autoconf.*'x'"
   cat > conftest.$ac_ext <<EOF
-#line 1800 "configure"
+#line 1816 "configure"
 #include "confdefs.h"
 #include <sgtty.h>
 Autoconf TIOCGETP
@@ -1814,7 +1830,7 @@ rm -f conftest*
 
   if test $ac_cv_prog_gcc_traditional = no; then
     cat > conftest.$ac_ext <<EOF
-#line 1818 "configure"
+#line 1834 "configure"
 #include "confdefs.h"
 #include <termio.h>
 Autoconf TCGETA
@@ -1836,12 +1852,12 @@ echo "$ac_t""$ac_cv_prog_gcc_traditional" 1>&6
 fi
 
 echo $ac_n "checking return type of signal handlers""... $ac_c" 1>&6
-echo "configure:1840: checking return type of signal handlers" >&5
+echo "configure:1856: checking return type of signal handlers" >&5
 if eval "test \"`echo '$''{'ac_cv_type_signal'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1845 "configure"
+#line 1861 "configure"
 #include "confdefs.h"
 #include <sys/types.h>
 #include <signal.h>
@@ -1858,7 +1874,7 @@ int main() {
 int i;
 ; return 0; }
 EOF
-if { (eval echo configure:1862: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1878: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   ac_cv_type_signal=void
 else
@@ -1877,12 +1893,12 @@ EOF
 
 
 echo $ac_n "checking for vprintf""... $ac_c" 1>&6
-echo "configure:1881: checking for vprintf" >&5
+echo "configure:1897: checking for vprintf" >&5
 if eval "test \"`echo '$''{'ac_cv_func_vprintf'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1886 "configure"
+#line 1902 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char vprintf(); below.  */
@@ -1905,7 +1921,7 @@ vprintf();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1909: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1925: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_vprintf=yes"
 else
@@ -1929,12 +1945,12 @@ fi
 
 if test "$ac_cv_func_vprintf" != yes; then
 echo $ac_n "checking for _doprnt""... $ac_c" 1>&6
-echo "configure:1933: checking for _doprnt" >&5
+echo "configure:1949: checking for _doprnt" >&5
 if eval "test \"`echo '$''{'ac_cv_func__doprnt'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1938 "configure"
+#line 1954 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char _doprnt(); below.  */
@@ -1957,7 +1973,7 @@ _doprnt();
 
 ; return 0; }
 EOF
-if { (eval echo configure:1961: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1977: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func__doprnt=yes"
 else
@@ -1984,12 +2000,12 @@ fi
 for ac_func in mkdir rmdir uname
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:1988: checking for $ac_func" >&5
+echo "configure:2004: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1993 "configure"
+#line 2009 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2012,7 +2028,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2016: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2032: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
@@ -2040,14 +2056,14 @@ done
 if test x$READLINE = xyes; then
 	
 echo $ac_n "checking for library containing tgetent""... $ac_c" 1>&6
-echo "configure:2044: checking for library containing tgetent" >&5
+echo "configure:2060: checking for library containing tgetent" >&5
 if eval "test \"`echo '$''{'ac_cv_search_tgetent'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   ac_func_search_save_LIBS="$LIBS"
 ac_cv_search_tgetent="no"
 cat > conftest.$ac_ext <<EOF
-#line 2051 "configure"
+#line 2067 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2058,7 +2074,7 @@ int main() {
 tgetent()
 ; return 0; }
 EOF
-if { (eval echo configure:2062: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2078: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_tgetent="none required"
 else
@@ -2069,7 +2085,7 @@ rm -f conftest*
 test "$ac_cv_search_tgetent" = "no" && for i in ncurses curses termcap termlib; do
 LIBS="-l$i  $ac_func_search_save_LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2073 "configure"
+#line 2089 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2080,7 +2096,7 @@ int main() {
 tgetent()
 ; return 0; }
 EOF
-if { (eval echo configure:2084: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2100: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   ac_cv_search_tgetent="-l$i"
 break
@@ -2113,7 +2129,7 @@ fi
 fi
 
 echo $ac_n "checking for dlopen in -ldl""... $ac_c" 1>&6
-echo "configure:2117: checking for dlopen in -ldl" >&5
+echo "configure:2133: checking for dlopen in -ldl" >&5
 ac_lib_var=`echo dl'_'dlopen | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2121,7 +2137,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-ldl  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2125 "configure"
+#line 2141 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2132,7 +2148,7 @@ int main() {
 dlopen()
 ; return 0; }
 EOF
-if { (eval echo configure:2136: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2152: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2163,17 +2179,17 @@ for ac_hdr in getopt.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:2167: checking for $ac_hdr" >&5
+echo "configure:2183: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2172 "configure"
+#line 2188 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2177: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2193: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -2202,7 +2218,7 @@ done
 
 if test x$READLINE = xyes; then
 	echo $ac_n "checking for readline in -lreadline""... $ac_c" 1>&6
-echo "configure:2206: checking for readline in -lreadline" >&5
+echo "configure:2222: checking for readline in -lreadline" >&5
 ac_lib_var=`echo readline'_'readline | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2210,7 +2226,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lreadline  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2214 "configure"
+#line 2230 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2221,7 +2237,7 @@ int main() {
 readline()
 ; return 0; }
 EOF
-if { (eval echo configure:2225: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2241: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2258,12 +2274,12 @@ package as well (which may be called readline-devel or something similar).
 fi
 
 	echo $ac_n "checking for rl_completion_matches""... $ac_c" 1>&6
-echo "configure:2262: checking for rl_completion_matches" >&5
+echo "configure:2278: checking for rl_completion_matches" >&5
 if eval "test \"`echo '$''{'ac_cv_func_rl_completion_matches'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2267 "configure"
+#line 2283 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char rl_completion_matches(); below.  */
@@ -2286,7 +2302,7 @@ rl_completion_matches();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2290: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2306: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_func_rl_completion_matches=yes"
 else
@@ -2643,3 +2659,10 @@ chmod +x $CONFIG_STATUS
 rm -fr confdefs* $ac_clean_files
 test "$no_create" = yes || ${CONFIG_SHELL-/bin/sh} $CONFIG_STATUS || exit 1
 
+
+if test x$ODIRECT != xyes; then
+  echo
+  echo Warning: O_DIRECT disabled.
+  echo Use of pvmove may cause machine to lock up under low memory conditions.
+  echo
+fi
diff --git a/configure.in b/configure.in
index f6420ca81..35f45b015 100644
--- a/configure.in
+++ b/configure.in
@@ -113,6 +113,14 @@ if test x$DEVMAPPER = xyes; then
 	CFLAGS="$CFLAGS -DDEVMAPPER_SUPPORT"
 fi
 
+dnl Disable O_DIRECT
+AC_ARG_ENABLE(o_direct, [  --disable-o_direct      Disable O_DIRECT],  \
+ODIRECT=no, ODIRECT=yes)
+
+if test x$ODIRECT = xyes; then
+	CFLAGS="$CFLAGS -DO_DIRECT_SUPPORT"
+fi
+
 dnl Mess with default exec_prefix
 if [[ "x$exec_prefix" = xNONE -a "x$prefix" = xNONE ]];
  then  exec_prefix="";
@@ -203,3 +211,10 @@ test/format1/Makefile							\
 test/regex/Makefile                                                     \
 test/filters/Makefile                                                   \
 )
+
+if test x$ODIRECT != xyes; then
+  echo
+  echo Warning: O_DIRECT disabled.
+  echo Use of pvmove may cause machine to lock up under low memory conditions.
+  echo
+fi
diff --git a/lib/device/dev-io.c b/lib/device/dev-io.c
index 897e7c008..8c64f526b 100644
--- a/lib/device/dev-io.c
+++ b/lib/device/dev-io.c
@@ -30,11 +30,15 @@
 #  define BLKGETSIZE64 DKIOCGETBLOCKCOUNT
 #  define BLKFLSBUF DKIOCSYNCHRONIZECACHE
 #  define BLKSIZE_SHIFT 0
+#endif
+
+#ifdef O_DIRECT_SUPPORT
 #  ifndef O_DIRECT
-#    define O_DIRECT	0
+#    error O_DIRECT support configured but O_DIRECT definition not found in headers
 #  endif
 #endif
 
+
 /* FIXME Use _llseek for 64-bit
 _syscall5(int,  _llseek,  uint,  fd, ulong, hi, ulong, lo, loff_t *, res, uint, wh);
  if (_llseek((unsigned) fd, (ulong) (offset >> 32), (ulong) (offset & 0xFFFFFFFF), &pos, SEEK_SET) < 0) { 
@@ -284,8 +288,10 @@ int dev_open_flags(struct device *dev, int flags, int direct, int quiet)
 		return 0;
 	}
 
+#ifdef O_DIRECT_SUPPORT
 	if (direct)
 		flags |= O_DIRECT;
+#endif
 
 	if ((dev->fd = open(name, flags, 0777)) < 0) {
 		log_sys_error("open", name);
@@ -302,7 +308,8 @@ int dev_open_flags(struct device *dev, int flags, int direct, int quiet)
 		dev->fd = -1;
 		return 0;
 	}
-#if !O_DIRECT
+
+#ifndef O_DIRECT_SUPPORT
 	if (!(dev->flags & DEV_REGULAR))
 		dev_flush(dev);
 #endif
@@ -353,7 +360,8 @@ int dev_close(struct device *dev)
 			  "which is not open.", dev_name(dev));
 		return 0;
 	}
-#if !O_DIRECT
+
+#ifndef O_DIRECT_SUPPORT
 	if (dev->flags & DEV_ACCESSED_W)
 		dev_flush(dev);
 #endif
@@ -406,7 +414,7 @@ int dev_append(struct device *dev, size_t len, void *buffer)
 	r = dev_write(dev, dev->end, len, buffer);
 	dev->end += (uint64_t) len;
 
-#if !O_DIRECT
+#ifndef O_DIRECT_SUPPORT
 	dev_flush(dev);
 #endif
 	return r;