diff --git a/.gitignore b/.gitignore
index a117161..55ecfb7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -62,6 +62,7 @@ stubdom/ioemu
 stubdom/ioemu/
 stubdom/libs-*
 stubdom/libxc-*
+stubdom/libxencall-*
 stubdom/libxenevtchn-*
 stubdom/libxengnttab-*
 stubdom/libxentoollog-*
@@ -91,6 +92,7 @@ config/Docs.mk
 tools/libs/toollog/headers.chk
 tools/libs/evtchn/headers.chk
 tools/libs/gnttab/headers.chk
+tools/libs/call/headers.chk
 tools/blktap2/daemon/blktapctrl
 tools/blktap2/drivers/img2qcow
 tools/blktap2/drivers/lock-util
diff --git a/stubdom/Makefile b/stubdom/Makefile
index 2dbf4a8..5bf4ed6 100644
--- a/stubdom/Makefile
+++ b/stubdom/Makefile
@@ -331,6 +331,12 @@ mk-headers-$(XEN_TARGET_ARCH): $(IOEMU_LINKFARM_TARGET)
 	  ln -sf $(XEN_ROOT)/tools/libs/gnttab/include/*.h include/ && \
 	  ln -sf $(XEN_ROOT)/tools/libs/gnttab/*.c . && \
 	  ln -sf $(XEN_ROOT)/tools/libs/gnttab/Makefile . )
+	mkdir -p libs-$(XEN_TARGET_ARCH)/call/include
+	[ -h libs-$(XEN_TARGET_ARCH)/call/Makefile ] || ( cd libs-$(XEN_TARGET_ARCH)/call && \
+	  ln -sf $(XEN_ROOT)/tools/libs/call/*.h . && \
+	  ln -sf $(XEN_ROOT)/tools/libs/call/include/*.h include/ && \
+	  ln -sf $(XEN_ROOT)/tools/libs/call/*.c . && \
+	  ln -sf $(XEN_ROOT)/tools/libs/call/Makefile . )
 	mkdir -p libxc-$(XEN_TARGET_ARCH)
 	[ -h libxc-$(XEN_TARGET_ARCH)/Makefile ] || ( cd libxc-$(XEN_TARGET_ARCH) && \
 	  ln -sf $(XEN_ROOT)/tools/libxc/*.h . && \
@@ -381,12 +387,21 @@ libs-$(XEN_TARGET_ARCH)/gnttab/libxengnttab.a: mk-headers-$(XEN_TARGET_ARCH) $(N
 	CPPFLAGS="$(TARGET_CPPFLAGS)" CFLAGS="$(TARGET_CFLAGS)" $(MAKE) DESTDIR= -C libs-$(XEN_TARGET_ARCH)/gnttab
 
 #######
+# libxencall
+#######
+
+.PHONY: libxencall
+libxencall: libs-$(XEN_TARGET_ARCH)/call/libxencall.a
+libs-$(XEN_TARGET_ARCH)/call/libxencall.a: mk-headers-$(XEN_TARGET_ARCH) $(NEWLIB_STAMPFILE)
+	CPPFLAGS="$(TARGET_CPPFLAGS)" CFLAGS="$(TARGET_CFLAGS)" $(MAKE) DESTDIR= -C libs-$(XEN_TARGET_ARCH)/call
+
+#######
 # libxc
 #######
 
 .PHONY: libxc
 libxc: libxc-$(XEN_TARGET_ARCH)/libxenctrl.a libxc-$(XEN_TARGET_ARCH)/libxenguest.a
-libxc-$(XEN_TARGET_ARCH)/libxenctrl.a: mk-headers-$(XEN_TARGET_ARCH) libxentoollog libxenevtchn libxengnttab cross-zlib
+libxc-$(XEN_TARGET_ARCH)/libxenctrl.a: mk-headers-$(XEN_TARGET_ARCH) libxentoollog libxenevtchn libxengnttab libxencall cross-zlib
 	CPPFLAGS="$(TARGET_CPPFLAGS)" CFLAGS="$(TARGET_CFLAGS)" $(MAKE) DESTDIR= CONFIG_LIBXC_MINIOS=y -C libxc-$(XEN_TARGET_ARCH)
 
  libxc-$(XEN_TARGET_ARCH)/libxenguest.a: libxc-$(XEN_TARGET_ARCH)/libxenctrl.a
diff --git a/tools/Makefile b/tools/Makefile
index f373e71..e5bbc98 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -263,6 +263,7 @@ subdir-all-qemu-xen-dir: qemu-xen-dir-find
 		-Wl,-rpath-link=$(XEN_ROOT)/tools/libs/toollog \
 		-Wl,-rpath-link=$(XEN_ROOT)/tools/libs/evtchn \
 		-Wl,-rpath-link=$(XEN_ROOT)/tools/libs/gnttab \
+		-Wl,-rpath-link=$(XEN_ROOT)/tools/libs/call \
 		$(QEMU_UPSTREAM_RPATH)" \
 		--bindir=$(LIBEXEC_BIN) \
 		--datadir=$(SHAREDIR)/qemu-xen \
diff --git a/tools/Rules.mk b/tools/Rules.mk
index 379990f..18e3688 100644
--- a/tools/Rules.mk
+++ b/tools/Rules.mk
@@ -13,6 +13,7 @@ XEN_INCLUDE        = $(XEN_ROOT)/tools/include
 XEN_LIBXENTOOLLOG  = $(XEN_ROOT)/tools/libs/toollog
 XEN_LIBXENEVTCHN   = $(XEN_ROOT)/tools/libs/evtchn
 XEN_LIBXENGNTTAB   = $(XEN_ROOT)/tools/libs/gnttab
+XEN_LIBXENCALL     = $(XEN_ROOT)/tools/libs/call
 XEN_LIBXC          = $(XEN_ROOT)/tools/libxc
 XEN_XENLIGHT       = $(XEN_ROOT)/tools/libxl
 XEN_XENSTORE       = $(XEN_ROOT)/tools/xenstore
@@ -98,8 +99,12 @@ CFLAGS_libxengntshr = -I$(XEN_LIBXENGNTTAB)/include $(CFLAGS_xeninclude)
 LDLIBS_libxengntshr = $(XEN_LIBXENGNTTAB)/libxengnttab$(libextension)
 SHLIB_libxengntshr  = -Wl,-rpath-link=$(XEN_LIBXENGNTTAB)
 
+CFLAGS_libxencall = -I$(XEN_LIBXENCALL)/include $(CFLAGS_xeninclude)
+LDLIBS_libxencall = $(XEN_LIBXENCALL)/libxencall$(libextension)
+SHLIB_libxencall  = -Wl,-rpath-link=$(XEN_LIBXENCALL)
+
 CFLAGS_libxenctrl = -I$(XEN_LIBXC)/include $(CFLAGS_libxentoollog) $(CFLAGS_xeninclude)
-SHDEPS_libxenctrl = $(SHLIB_libxentoollog) $(SHLIB_libxenevtchn) $(SHLIB_libxengnttab) $(SHLIB_libxengntshr)
+SHDEPS_libxenctrl = $(SHLIB_libxentoollog) $(SHLIB_libxenevtchn) $(SHLIB_libxengnttab) $(SHLIB_libxengntshr) $(SHLIB_libxencall)
 LDLIBS_libxenctrl = $(SHDEPS_libxenctrl) $(XEN_LIBXC)/libxenctrl$(libextension)
 SHLIB_libxenctrl  = $(SHDEPS_libxenctrl) -Wl,-rpath-link=$(XEN_LIBXC)
 
diff --git a/tools/libs/Makefile b/tools/libs/Makefile
index 00156ae..f4f5d57 100644
--- a/tools/libs/Makefile
+++ b/tools/libs/Makefile
@@ -5,5 +5,6 @@ SUBDIRS-y :=
 SUBDIRS-y += toollog
 SUBDIRS-y += evtchn
 SUBDIRS-y += gnttab
+SUBDIRS-y += call
 
 all clean install distclean: %: subdirs-%
diff --git a/tools/libs/call/Makefile b/tools/libs/call/Makefile
new file mode 100644
index 0000000..9402ea5
--- /dev/null
+++ b/tools/libs/call/Makefile
@@ -0,0 +1,71 @@
+XEN_ROOT = $(CURDIR)/../../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+MAJOR    = 1
+MINOR    = 0
+SHLIB_LDFLAGS += -Wl,--version-script=libxencall.map
+
+CFLAGS   += -Werror -Wmissing-prototypes
+CFLAGS   += -I./include $(CFLAGS_xeninclude)
+CFLAGS   += $(CFLAGS_libxentoollog)
+
+SRCS-y                 += core.c buffer.c
+SRCS-$(CONFIG_Linux)   += linux.c
+SRCS-$(CONFIG_FreeBSD) += freebsd.c
+SRCS-$(CONFIG_SunOS)   += solaris.c
+SRCS-$(CONFIG_NetBSD)  += netbsd.c
+SRCS-$(CONFIG_MiniOS)  += minios.c
+
+LIB_OBJS := $(patsubst %.c,%.o,$(SRCS-y))
+PIC_OBJS := $(patsubst %.c,%.opic,$(SRCS-y))
+
+LIB := libxencall.a
+ifneq ($(nosharedlibs),y)
+LIB += libxencall.so
+endif
+
+.PHONY: all
+all: build
+
+.PHONY: build
+build:
+	$(MAKE) libs
+
+.PHONY: libs
+libs: headers.chk $(LIB)
+
+headers.chk: $(wildcard include/*.h)
+
+libxencall.a: $(LIB_OBJS)
+	$(AR) rc $@ $^
+
+libxencall.so: libxencall.so.$(MAJOR)
+	$(SYMLINK_SHLIB) $< $@
+libxencall.so.$(MAJOR): libxencall.so.$(MAJOR).$(MINOR)
+	$(SYMLINK_SHLIB) $< $@
+
+libxencall.so.$(MAJOR).$(MINOR): $(PIC_OBJS) libxencall.map
+	$(CC) $(LDFLAGS) $(PTHREAD_LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxencall.so.$(MAJOR) $(SHLIB_LDFLAGS) -o $@ $(PIC_OBJS) $(LDLIBS_libxentoollog) $(APPEND_LDFLAGS)
+
+.PHONY: install
+install: build
+	$(INSTALL_DIR) $(DESTDIR)$(libdir)
+	$(INSTALL_DIR) $(DESTDIR)$(includedir)
+	$(INSTALL_SHLIB) libxencall.so.$(MAJOR).$(MINOR) $(DESTDIR)$(libdir)
+	$(INSTALL_DATA) libxencall.a $(DESTDIR)$(libdir)
+	$(SYMLINK_SHLIB) libxencall.so.$(MAJOR).$(MINOR) $(DESTDIR)$(libdir)/libxencall.so.$(MAJOR)
+	$(SYMLINK_SHLIB) libxencall.so.$(MAJOR) $(DESTDIR)$(libdir)/libxencall.so
+	$(INSTALL_DATA) include/xencall.h $(DESTDIR)$(includedir)
+
+.PHONY: TAGS
+TAGS:
+	etags -t *.c *.h
+
+.PHONY: clean
+clean:
+	rm -rf *.rpm $(LIB) *~ $(DEPS) $(LIB_OBJS) $(PIC_OBJS)
+	rm -f libxencall.so.$(MAJOR).$(MINOR) libxencall.so.$(MAJOR)
+	rm -f headers.chk
+
+.PHONY: distclean
+distclean: clean
diff --git a/tools/libs/call/buffer.c b/tools/libs/call/buffer.c
new file mode 100644
index 0000000..1a1b27a
--- /dev/null
+++ b/tools/libs/call/buffer.c
@@ -0,0 +1,192 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <pthread.h>
+
+#include "private.h"
+
+#define DBGPRINTF(_m...) \
+	xtl_log(xcall->logger, XTL_DEBUG, -1, "xencall:buffer", _m)
+
+#define ROUNDUP(_x,_w) (((unsigned long)(_x)+(1UL<<(_w))-1) & ~((1UL<<(_w))-1))
+
+pthread_mutex_t cache_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+static void cache_lock(xencall_handle *xcall)
+{
+    int saved_errno = errno;
+    if ( xcall->flags & XENCALL_OPENFLAG_NON_REENTRANT )
+        return;
+    pthread_mutex_lock(&cache_mutex);
+    /* Ignore pthread errors. */
+    errno = saved_errno;
+}
+
+static void cache_unlock(xencall_handle *xcall)
+{
+    int saved_errno = errno;
+    if ( xcall->flags & XENCALL_OPENFLAG_NON_REENTRANT )
+        return;
+    pthread_mutex_unlock(&cache_mutex);
+    /* Ignore pthread errors. */
+    errno = saved_errno;
+}
+
+static void *cache_alloc(xencall_handle *xcall, size_t nr_pages)
+{
+    void *p = NULL;
+
+    cache_lock(xcall);
+
+    xcall->buffer_total_allocations++;
+    xcall->buffer_current_allocations++;
+    if ( xcall->buffer_current_allocations > xcall->buffer_maximum_allocations )
+        xcall->buffer_maximum_allocations = xcall->buffer_current_allocations;
+
+    if ( nr_pages > 1 )
+    {
+        xcall->buffer_cache_toobig++;
+    }
+    else if ( xcall->buffer_cache_nr > 0 )
+    {
+        p = xcall->buffer_cache[--xcall->buffer_cache_nr];
+        xcall->buffer_cache_hits++;
+    }
+    else
+    {
+        xcall->buffer_cache_misses++;
+    }
+
+    cache_unlock(xcall);
+
+    return p;
+}
+
+static int cache_free(xencall_handle *xcall, void *p, size_t nr_pages)
+{
+    int rc = 0;
+
+    cache_lock(xcall);
+
+    xcall->buffer_total_releases++;
+    xcall->buffer_current_allocations--;
+
+    if ( nr_pages == 1 &&
+	 xcall->buffer_cache_nr < BUFFER_CACHE_SIZE )
+    {
+        xcall->buffer_cache[xcall->buffer_cache_nr++] = p;
+        rc = 1;
+    }
+
+    cache_unlock(xcall);
+
+    return rc;
+}
+
+void buffer_release_cache(xencall_handle *xcall)
+{
+    void *p;
+
+    cache_lock(xcall);
+
+    DBGPRINTF("total allocations:%d total releases:%d",
+              xcall->buffer_total_allocations,
+              xcall->buffer_total_releases);
+    DBGPRINTF("current allocations:%d maximum allocations:%d",
+              xcall->buffer_current_allocations,
+              xcall->buffer_maximum_allocations);
+    DBGPRINTF("cache current size:%d",
+              xcall->buffer_cache_nr);
+    DBGPRINTF("cache hits:%d misses:%d toobig:%d",
+              xcall->buffer_cache_hits,
+              xcall->buffer_cache_misses,
+              xcall->buffer_cache_toobig);
+
+    while ( xcall->buffer_cache_nr > 0 )
+    {
+        p = xcall->buffer_cache[--xcall->buffer_cache_nr];
+        osdep_free_pages(xcall, p, 1);
+    }
+
+    cache_unlock(xcall);
+}
+
+void *xencall_alloc_buffer_pages(xencall_handle *xcall, size_t nr_pages)
+{
+    void *p = cache_alloc(xcall, nr_pages);
+
+    if ( !p )
+        p = osdep_alloc_pages(xcall, nr_pages);
+
+    if (!p)
+        return NULL;
+
+    memset(p, 0, nr_pages * PAGE_SIZE);
+
+    return p;
+}
+
+void xencall_free_buffer_pages(xencall_handle *xcall, void *p, size_t nr_pages)
+{
+    if ( p == NULL )
+        return;
+
+    if ( !cache_free(xcall, p, nr_pages) )
+        osdep_free_pages(xcall, p, nr_pages);
+}
+
+struct allocation_header {
+    int nr_pages;
+};
+
+void *xencall_alloc_buffer(xencall_handle *xcall, size_t size)
+{
+    size_t actual_size = ROUNDUP(size + sizeof(struct allocation_header), PAGE_SHIFT);
+    int nr_pages = actual_size >> PAGE_SHIFT;
+    struct allocation_header *hdr;
+
+    hdr = xencall_alloc_buffer_pages(xcall, nr_pages);
+    if ( hdr == NULL )
+        return NULL;
+
+    hdr->nr_pages = nr_pages;
+
+    return (void *)(hdr+1);
+}
+
+void xencall_free_buffer(xencall_handle *xcall, void *p)
+{
+    struct allocation_header *hdr;
+
+    if (p == NULL)
+        return;
+
+    hdr = p;
+    --hdr;
+
+    xencall_free_buffer_pages(xcall, hdr, hdr->nr_pages);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/core.c b/tools/libs/call/core.c
new file mode 100644
index 0000000..a342871
--- /dev/null
+++ b/tools/libs/call/core.c
@@ -0,0 +1,147 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+
+#include "private.h"
+
+xencall_handle *xencall_open(xentoollog_logger *logger, unsigned open_flags)
+{
+	xencall_handle *xcall = malloc(sizeof(*xcall));
+    int rc;
+
+    if (!xcall) return NULL;
+
+    xcall->flags = open_flags;
+    xcall->buffer_cache_nr = 0;
+
+    xcall->buffer_total_allocations = 0;
+    xcall->buffer_total_releases = 0;
+    xcall->buffer_current_allocations = 0;
+    xcall->buffer_maximum_allocations = 0;
+    xcall->buffer_cache_hits = 0;
+    xcall->buffer_cache_misses = 0;
+    xcall->buffer_cache_toobig = 0;
+    xcall->logger = logger;
+    xcall->logger_tofree = NULL;
+
+    if (!xcall->logger) {
+        xcall->logger = xcall->logger_tofree =
+            (xentoollog_logger*)
+            xtl_createlogger_stdiostream(stderr, XTL_PROGRESS, 0);
+        if (!xcall->logger) goto err;
+    }
+
+    rc = osdep_xencall_open(xcall);
+    if ( rc  < 0 ) goto err;
+
+    return xcall;
+
+err:
+    osdep_xencall_close(xcall);
+    xtl_logger_destroy(xcall->logger_tofree);
+    free(xcall);
+    return NULL;
+}
+
+int xencall_close(xencall_handle *xcall)
+{
+    int rc;
+
+    if ( !xcall )
+        return 0;
+
+    rc = osdep_xencall_close(xcall);
+    buffer_release_cache(xcall);
+    xtl_logger_destroy(xcall->logger_tofree);
+    free(xcall);
+    return rc;
+}
+
+int xencall0(xencall_handle *xcall, unsigned int op)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+int xencall1(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+        .arg = { arg1 },
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+int xencall2(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+        .arg = { arg1, arg2 },
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+int xencall3(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+        .arg = { arg1, arg2, arg3},
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+int xencall4(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3,
+             uint64_t arg4)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+        .arg = { arg1, arg2, arg3, arg4 },
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+int xencall5(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3,
+             uint64_t arg4, uint64_t arg5)
+{
+    privcmd_hypercall_t call = {
+        .op = op,
+        .arg = { arg1, arg2, arg3, arg4, arg5 },
+    };
+
+    return osdep_hypercall(xcall, &call);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/freebsd.c b/tools/libs/call/freebsd.c
new file mode 100644
index 0000000..2413966
--- /dev/null
+++ b/tools/libs/call/freebsd.c
@@ -0,0 +1,140 @@
+ /******************************************************************************
+ *
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Split from xc_freebsd_osdep.c
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+
+#include "private.h"
+
+#define PRIVCMD_DEV     "/dev/xen/privcmd"
+
+int osdep_xencall_open(xencall_handle *xcall)
+{
+    int flags, saved_errno;
+    int fd = open(PRIVCMD_DEV, O_RDWR);
+
+    if ( fd == -1 )
+    {
+        PERROR("Could not obtain handle on privileged command interface "
+               PRIVCMD_DEV);
+        return -1;
+    }
+
+    /*
+     * Although we return the file handle as the 'xc handle' the API
+     * does not specify / guarentee that this integer is in fact
+     * a file handle. Thus we must take responsiblity to ensure
+     * it doesn't propagate (ie leak) outside the process.
+     */
+    if ( (flags = fcntl(fd, F_GETFD)) < 0 )
+    {
+        PERROR("Could not get file handle flags");
+        goto error;
+    }
+
+    flags |= FD_CLOEXEC;
+
+    if ( fcntl(fd, F_SETFD, flags) < 0 )
+    {
+        PERROR("Could not set file handle flags");
+        goto error;
+    }
+
+    xcall->fd = fd;
+    return 0;
+
+ error:
+    saved_errno = errno;
+    close(fd);
+    errno = saved_errno;
+
+    return -1;
+}
+
+int osdep_xencall_close(xencall_handle *xcall)
+{
+    int fd = xcall->fd;
+    if ( fd == -1 )
+        return 0;
+    return close(fd);
+}
+
+int osdep_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
+{
+    int fd = xcall->fd;
+    int ret;
+
+    ret = ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
+
+    return (ret == 0) ? hypercall->retval : ret;
+}
+
+void *osdep_alloc_pages(xencall_handle *xcall, size_t npages)
+{
+    size_t size = npages * PAGE_SIZE;
+    void *p;
+
+    /* Address returned by mmap is page aligned. */
+    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
+             -1, 0);
+    if (p == NULL)
+        return NULL;
+
+    /*
+     * Since FreeBSD doesn't have the MAP_LOCKED flag,
+     * lock memory using mlock.
+     */
+    if ( mlock(p, size) < 0 )
+    {
+        munmap(p, size);
+        return NULL;
+    }
+
+    return p;
+}
+
+void osdep_free_pages(xencall_handle *xcall, void *ptr, size_t npages)
+{
+    int saved_errno = errno;
+    /* Unlock pages */
+    munlock(ptr, npages * PAGE_SIZE);
+
+    munmap(ptr, npages * PAGE_SIZE);
+    /* We MUST propagate the hypercall errno, not unmap call's. */
+    errno = saved_errno;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/include/xencall.h b/tools/libs/call/include/xencall.h
new file mode 100644
index 0000000..0d91aa8
--- /dev/null
+++ b/tools/libs/call/include/xencall.h
@@ -0,0 +1,84 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef XENCALL_H
+#define XENCALL_H
+
+/*
+ * This library allows you to make arbitrary hypercalls (subject to
+ * sufficient permission for the process and the domain itself). Note
+ * that while the library interface is stable the hypercalls are
+ * subject to their own rules.
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+
+/* Callers who don't care don't need to #include <xentoollog.h> */
+typedef struct xentoollog_logger xentoollog_logger;
+
+typedef struct xencall_handle xencall_handle;
+
+/*
+ */
+#define XENCALL_OPENFLAG_NON_REENTRANT (1U<<0)
+
+/*
+ * Return a handle onto the hypercall driver.  Logs errors.
+ */
+xencall_handle *xencall_open(xentoollog_logger *logger, unsigned open_flags);
+
+/*
+ * Close a handle previously allocated with xencall_open().
+ */
+int xencall_close(xencall_handle *xcall);
+
+/*
+ * Call hypercalls with varying numbers of arguments.
+ */
+int xencall0(xencall_handle *xcall, unsigned int op);
+int xencall1(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1);
+int xencall2(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2);
+int xencall3(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3);
+int xencall4(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3,
+             uint64_t arg4);
+int xencall5(xencall_handle *xcall, unsigned int op,
+             uint64_t arg1, uint64_t arg2, uint64_t arg3,
+             uint64_t arg4, uint64_t arg5);
+
+/*
+ * Allocate and free memory which is suitable for use as a pointer
+ * argument to a hypercall.
+ */
+void *xencall_alloc_buffer_pages(xencall_handle *xcall, size_t nr_pages);
+void xencall_free_buffer_pages(xencall_handle *xcall, void *p, size_t nr_pages);
+
+void *xencall_alloc_buffer(xencall_handle *xcall, size_t size);
+void xencall_free_buffer(xencall_handle *xcall, void *p);
+
+#endif
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/libxencall.map b/tools/libs/call/libxencall.map
new file mode 100644
index 0000000..2f96144
--- /dev/null
+++ b/tools/libs/call/libxencall.map
@@ -0,0 +1,19 @@
+VERS_1.0 {
+	global:
+		xencall_open;
+		xencall_close;
+
+		xencall0;
+		xencall1;
+		xencall2;
+		xencall3;
+		xencall4;
+		xencall5;
+		xencall6;
+
+		xencall_alloc_buffer;
+		xencall_free_buffer;
+		xencall_alloc_buffer_pages;
+		xencall_free_buffer_pages;
+	local: *; /* Do not expose anything by default */
+};
diff --git a/tools/libs/call/linux.c b/tools/libs/call/linux.c
new file mode 100644
index 0000000..55e1e83
--- /dev/null
+++ b/tools/libs/call/linux.c
@@ -0,0 +1,138 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Split out from xc_linus_osdep.c:
+ *
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <sys/mman.h>
+#include <sys/ioctl.h>
+
+#include "private.h"
+
+int osdep_xencall_open(xencall_handle *xcall)
+{
+    int flags, saved_errno;
+    int fd = open("/dev/xen/privcmd", O_RDWR); /* prefer this newer interface */
+
+    if ( fd == -1 && ( errno == ENOENT || errno == ENXIO || errno == ENODEV ))
+    {
+        /* Fallback to /proc/xen/privcmd */
+        fd = open("/proc/xen/privcmd", O_RDWR);
+    }
+
+    if ( fd == -1 )
+    {
+        PERROR("Could not obtain handle on privileged command interface");
+        return -1;
+    }
+
+    /* Although we return the file handle as the 'xc handle' the API
+       does not specify / guarentee that this integer is in fact
+       a file handle. Thus we must take responsiblity to ensure
+       it doesn't propagate (ie leak) outside the process */
+    if ( (flags = fcntl(fd, F_GETFD)) < 0 )
+    {
+        PERROR("Could not get file handle flags");
+        goto error;
+    }
+
+    flags |= FD_CLOEXEC;
+
+    if ( fcntl(fd, F_SETFD, flags) < 0 )
+    {
+        PERROR("Could not set file handle flags");
+        goto error;
+    }
+
+    xcall->fd = fd;
+    return 0;
+
+ error:
+    saved_errno = errno;
+    close(fd);
+    errno = saved_errno;
+    return -1;
+}
+
+int osdep_xencall_close(xencall_handle *xcall)
+{
+    int fd = xcall->fd;
+    if (fd == -1)
+        return 0;
+    return close(fd);
+}
+
+int osdep_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
+{
+    return ioctl(xcall->fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
+}
+
+void *osdep_alloc_pages(xencall_handle *xcall, size_t npages)
+{
+    size_t size = npages * PAGE_SIZE;
+    void *p;
+    int rc, saved_errno;
+
+    /* Address returned by mmap is page aligned. */
+    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_LOCKED, -1, 0);
+    if ( p == MAP_FAILED )
+    {
+        PERROR("xc_alloc_hypercall_buffer: mmap failed");
+        return NULL;
+    }
+
+    /* Do not copy the VMA to child process on fork. Avoid the page being COW
+        on hypercall. */
+    rc = madvise(p, npages * PAGE_SIZE, MADV_DONTFORK);
+    if ( rc < 0 )
+    {
+        PERROR("xc_alloc_hypercall_buffer: madvise failed");
+        goto out;
+    }
+
+    return p;
+
+out:
+    saved_errno = errno;
+    (void)munmap(p, size);
+    errno = saved_errno;
+    return NULL;
+}
+
+void osdep_free_pages(xencall_handle *xcall, void *ptr, size_t npages)
+{
+    int saved_errno = errno;
+    /* Recover the VMA flags. Maybe it's not necessary */
+    madvise(ptr, npages * PAGE_SIZE, MADV_DOFORK);
+
+    munmap(ptr, npages * PAGE_SIZE);
+    /* We MUST propagate the hypercall errno, not unmap call's. */
+    errno = saved_errno;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/minios.c b/tools/libs/call/minios.c
new file mode 100644
index 0000000..3bee7be
--- /dev/null
+++ b/tools/libs/call/minios.c
@@ -0,0 +1,81 @@
+/*
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Split out from xc_minios.c
+ *
+ * Copyright 2007-2008 Samuel Thibault <samuel.thibault@eu.citrix.com>.
+ */
+
+#include <mini-os/types.h>
+#include <mini-os/os.h>
+#include <mini-os/mm.h>
+#include <mini-os/lib.h>
+
+#include <errno.h>
+#include <malloc.h>
+
+#include "private.h"
+
+int osdep_xencall_open(xencall_handle *xcall)
+{
+    /* No fd required */
+    return 0;
+}
+
+int osdep_xencall_close(xencall_handle *xcall)
+{
+    return 0;
+}
+
+int osdep_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
+{
+    multicall_entry_t call;
+    int i, ret;
+
+    call.op = hypercall->op;
+    for (i = 0; i < 5; i++)
+        call.args[i] = hypercall->arg[i];
+
+    ret = HYPERVISOR_multicall(&call, 1);
+
+    if (ret < 0) {
+	errno = -ret;
+	return -1;
+    }
+    if ((long) call.result < 0) {
+        errno = - (long) call.result;
+        return -1;
+    }
+    return call.result;
+}
+
+void *osdep_alloc_pages(xencall_handle *xcall, size_t npages)
+{
+    return memalign(PAGE_SIZE, npages * PAGE_SIZE);
+}
+
+void osdep_free_pages(xencall_handle *xcall, void *ptr, size_t npages)
+{
+    free(ptr);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/netbsd.c b/tools/libs/call/netbsd.c
new file mode 100644
index 0000000..2aa02f1
--- /dev/null
+++ b/tools/libs/call/netbsd.c
@@ -0,0 +1,121 @@
+/******************************************************************************
+ *
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Split from xc_netbsd.c
+ */
+
+#include "xc_private.h"
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <malloc.h>
+#include <sys/mman.h>
+
+int osdep_xencall_open(xencall_handle *xcall)
+{
+    int flags, saved_errno;
+    int fd = open("/kern/xen/privcmd", O_RDWR);
+
+    if ( fd == -1 )
+    {
+        PERROR("Could not obtain handle on privileged command interface");
+        return -1;
+    }
+
+    /* Although we return the file handle as the 'xc handle' the API
+       does not specify / guarentee that this integer is in fact
+       a file handle. Thus we must take responsiblity to ensure
+       it doesn't propagate (ie leak) outside the process */
+    if ( (flags = fcntl(fd, F_GETFD)) < 0 )
+    {
+        PERROR("Could not get file handle flags");
+        goto error;
+    }
+    flags |= FD_CLOEXEC;
+    if ( fcntl(fd, F_SETFD, flags) < 0 )
+    {
+        PERROR("Could not set file handle flags");
+        goto error;
+    }
+
+    xcall->fd = fd;
+    return 0;
+
+ error:
+    saved_errno = errno;
+    close(fd);
+    errno = saved_errno;
+    return -1;
+}
+
+int osdep_xencall_close(xencall_handle *xcall)
+{
+    int fd = xcall->fd;
+    return close(fd);
+}
+
+void *osdep_alloc_hypercall_buffer(xencall_handle *xcall, size_t npages)
+{
+    size_t size = npages * XC_PAGE_SIZE;
+    void *p;
+
+    p = xc_memalign(xcall, XC_PAGE_SIZE, size);
+    if (!p)
+        return NULL;
+
+    if ( mlock(p, size) < 0 )
+    {
+        free(p);
+        return NULL;
+    }
+    return p;
+}
+
+void osdep_free_hypercall_buffer(xencall_handle *xcall, void *ptr,
+                                 size_t npages)
+{
+    (void) munlock(ptr, npages * XC_PAGE_SIZE);
+    free(ptr);
+}
+
+int do_xen_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
+{
+    int fd = xcall->fd;
+    int error = ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
+
+    /*
+     * Since NetBSD ioctl can only return 0 on success or < 0 on
+     * error, if we want to return a value from ioctl we should
+     * do so by setting hypercall->retval, to mimic Linux ioctl
+     * implementation.
+     */
+    if (error < 0)
+        return error;
+    else
+        return hypercall->retval;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/private.h b/tools/libs/call/private.h
new file mode 100644
index 0000000..37dd15f
--- /dev/null
+++ b/tools/libs/call/private.h
@@ -0,0 +1,68 @@
+#ifndef XENCALL_PRIVATE_H
+#define XENCALL_PRIVATE_H
+
+#include <xentoollog.h>
+
+#include <xencall.h>
+
+#include <xen/xen.h>
+#include <xen/sys/privcmd.h>
+
+#ifndef PAGE_SHIFT /* Mini-os, Yukk */
+#define PAGE_SHIFT           12
+#endif
+#ifndef __MINIOS__ /* Yukk */
+#define PAGE_SIZE            (1UL << PAGE_SHIFT)
+#define PAGE_MASK            (~(PAGE_SIZE-1))
+#endif
+
+struct xencall_handle {
+    xentoollog_logger *logger, *logger_tofree;
+    unsigned flags;
+    int fd;
+
+    /*
+     * A simple cache of unused, single page, hypercall buffers
+     *
+     * Protected by a global lock.
+     */
+#define BUFFER_CACHE_SIZE 4
+    int buffer_cache_nr;
+    void *buffer_cache[BUFFER_CACHE_SIZE];
+
+    /*
+     * Hypercall buffer statistics. All protected by the global
+     * buffer_cache lock.
+     */
+    int buffer_total_allocations;
+    int buffer_total_releases;
+    int buffer_current_allocations;
+    int buffer_maximum_allocations;
+    int buffer_cache_hits;
+    int buffer_cache_misses;
+    int buffer_cache_toobig;
+};
+
+int osdep_xencall_open(xencall_handle *xcall);
+int osdep_xencall_close(xencall_handle *xcall);
+
+int osdep_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall);
+
+void *osdep_alloc_pages(xencall_handle *xcall, size_t nr_pages);
+void osdep_free_pages(xencall_handle *xcall, void *p, size_t nr_pages);
+
+void buffer_release_cache(xencall_handle *xcall);
+
+#define PERROR(_f...) xtl_log(xcall->logger, XTL_ERROR, errno, "xencall", _f)
+
+#endif
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libs/call/solaris.c b/tools/libs/call/solaris.c
new file mode 100644
index 0000000..945d867
--- /dev/null
+++ b/tools/libs/call/solaris.c
@@ -0,0 +1,97 @@
+/******************************************************************************
+ *
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Split from xc_solaris.c
+ */
+
+#include "xc_private.h"
+
+#include <xen/memory.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <malloc.h>
+
+int osdep_xencall_open(xencall_handle *xcall)
+{
+    int flags, saved_errno;
+    int fd = open("/dev/xen/privcmd", O_RDWR);
+
+    if ( fd == -1 )
+    {
+        PERROR("Could not obtain handle on privileged command interface");
+        return -1;
+    }
+
+    /* Although we return the file handle as the 'xc handle' the API
+       does not specify / guarentee that this integer is in fact
+       a file handle. Thus we must take responsiblity to ensure
+       it doesn't propagate (ie leak) outside the process */
+    if ( (flags = fcntl(fd, F_GETFD)) < 0 )
+    {
+        PERROR("Could not get file handle flags");
+        goto error;
+    }
+    flags |= FD_CLOEXEC;
+    if ( fcntl(fd, F_SETFD, flags) < 0 )
+    {
+        PERROR("Could not set file handle flags");
+        goto error;
+    }
+
+    xcall->fd = fd;
+    return 0;
+
+ error:
+    saved_errno = errno;
+    close(fd);
+    errno = saved_errno;
+    return -1;
+}
+
+int osdep_xencall_close(xencall_handle *xcall)
+{
+    int fd = xcall->fd;
+    return close(fd);
+}
+
+void *osdep_alloc_hypercall_buffer(xencall_handle *xcall, size_t npages)
+{
+    return xc_memalign(xcall, XC_PAGE_SIZE, npages * XC_PAGE_SIZE);
+}
+
+void osdep_free_hypercall_buffer(xencall_handle *xcall, void *ptr,
+                                 size_t npages)
+{
+    free(ptr);
+}
+
+int do_xen_hypercall(xencall_handle *xcall, privcmd_hypercall_t *hypercall)
+{
+    int fd = xcall->fd;
+    return ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/libxc/Makefile b/tools/libxc/Makefile
index 3305fdd..a122f73 100644
--- a/tools/libxc/Makefile
+++ b/tools/libxc/Makefile
@@ -122,6 +122,11 @@ GUEST_PIC_OBJS := $(patsubst %.c,%.opic,$(GUEST_SRCS-y))
 $(CTRL_LIB_OBJS) $(GUEST_LIB_OBJS) \
 $(CTRL_PIC_OBJS) $(GUEST_PIC_OBJS): CFLAGS += -include $(XEN_ROOT)/tools/config.h
 
+# libxenguest includes xc_private.h, so needs this despite not using
+# this functionality directly.
+$(CTRL_LIB_OBJS) $(GUEST_LIB_OBJS) \
+$(CTRL_PIC_OBJS) $(GUEST_PIC_OBJS): CFLAGS += $(CFLAGS_libxencall)
+
 $(CTRL_LIB_OBJS) $(CTRL_PIC_OBJS): CFLAGS += $(CFLAGS_libxengnttab) $(CFLAGS_libxengntshr)
 
 LIB := libxenctrl.a
@@ -202,7 +207,7 @@ libxenctrl.so.$(MAJOR): libxenctrl.so.$(MAJOR).$(MINOR)
 	$(SYMLINK_SHLIB) $< $@
 
 libxenctrl.so.$(MAJOR).$(MINOR): $(CTRL_PIC_OBJS)
-	$(CC) $(LDFLAGS) $(PTHREAD_LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxenctrl.so.$(MAJOR) $(SHLIB_LDFLAGS) -o $@ $^ $(LDLIBS_libxentoollog) $(LDLIBS_libxenevtchn) $(LDLIBS_libxengnttab) $(LDLIBS_libxengntshr) $(PTHREAD_LIBS) $(APPEND_LDFLAGS)
+	$(CC) $(LDFLAGS) $(PTHREAD_LDFLAGS) -Wl,$(SONAME_LDFLAG) -Wl,libxenctrl.so.$(MAJOR) $(SHLIB_LDFLAGS) -o $@ $^ $(LDLIBS_libxentoollog) $(LDLIBS_libxenevtchn) $(LDLIBS_libxengnttab) $(LDLIBS_libxengntshr) $(LDLIBS_libxencall) $(PTHREAD_LIBS) $(APPEND_LDFLAGS)
 
 # libxenguest
 
diff --git a/tools/libxc/xc_altp2m.c b/tools/libxc/xc_altp2m.c
index 87a0fdf..0639632 100644
--- a/tools/libxc/xc_altp2m.c
+++ b/tools/libxc/xc_altp2m.c
@@ -27,22 +27,18 @@
 int xc_altp2m_get_domain_state(xc_interface *handle, domid_t dom, bool *state)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_get_domain_state;
     arg->domain = dom;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     if ( !rc )
         *state = arg->u.domain_state.state;
@@ -54,23 +50,19 @@ int xc_altp2m_get_domain_state(xc_interface *handle, domid_t dom, bool *state)
 int xc_altp2m_set_domain_state(xc_interface *handle, domid_t dom, bool state)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_set_domain_state;
     arg->domain = dom;
     arg->u.domain_state.state = state;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -81,24 +73,20 @@ int xc_altp2m_set_vcpu_enable_notify(xc_interface *handle, domid_t domid,
                                      uint32_t vcpuid, xen_pfn_t gfn)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_vcpu_enable_notify;
     arg->domain = domid;
     arg->u.enable_notify.vcpu_id = vcpuid;
     arg->u.enable_notify.gfn = gfn;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -108,24 +96,20 @@ int xc_altp2m_create_view(xc_interface *handle, domid_t domid,
                           xenmem_access_t default_access, uint16_t *view_id)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_create_p2m;
     arg->domain = domid;
     arg->u.view.view = -1;
     arg->u.view.hvmmem_default_access = default_access;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     if ( !rc )
         *view_id = arg->u.view.view;
@@ -138,23 +122,19 @@ int xc_altp2m_destroy_view(xc_interface *handle, domid_t domid,
                            uint16_t view_id)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_destroy_p2m;
     arg->domain = domid;
     arg->u.view.view = view_id;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -165,23 +145,19 @@ int xc_altp2m_switch_to_view(xc_interface *handle, domid_t domid,
                              uint16_t view_id)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_switch_p2m;
     arg->domain = domid;
     arg->u.view.view = view_id;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -192,17 +168,12 @@ int xc_altp2m_set_mem_access(xc_interface *handle, domid_t domid,
                              xenmem_access_t access)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_set_mem_access;
     arg->domain = domid;
@@ -210,7 +181,8 @@ int xc_altp2m_set_mem_access(xc_interface *handle, domid_t domid,
     arg->u.set_mem_access.hvmmem_access = access;
     arg->u.set_mem_access.gfn = gfn;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -221,17 +193,12 @@ int xc_altp2m_change_gfn(xc_interface *handle, domid_t domid,
                          xen_pfn_t new_gfn)
 {
     int rc;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_altp2m_op_t, arg);
 
     arg = xc_hypercall_buffer_alloc(handle, arg, sizeof(*arg));
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_altp2m;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->version = HVMOP_ALTP2M_INTERFACE_VERSION;
     arg->cmd = HVMOP_altp2m_change_gfn;
     arg->domain = domid;
@@ -239,7 +206,8 @@ int xc_altp2m_change_gfn(xc_interface *handle, domid_t domid,
     arg->u.change_gfn.old_gfn = old_gfn;
     arg->u.change_gfn.new_gfn = new_gfn;
 
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op, HVMOP_altp2m,
+		  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(handle, arg);
     return rc;
diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
index 96506d5..8fde415 100644
--- a/tools/libxc/xc_domain.c
+++ b/tools/libxc/xc_domain.c
@@ -122,7 +122,6 @@ int xc_domain_shutdown(xc_interface *xch,
                        int reason)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(sched_remote_shutdown_t, arg);
 
     arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
@@ -132,13 +131,11 @@ int xc_domain_shutdown(xc_interface *xch,
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_sched_op;
-    hypercall.arg[0] = (unsigned long)SCHEDOP_remote_shutdown;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
     arg->domain_id = domid;
     arg->reason = reason;
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_sched_op,
+                   SCHEDOP_remote_shutdown,
+                   HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -561,7 +558,6 @@ int xc_watchdog(xc_interface *xch,
                 uint32_t timeout)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(sched_watchdog_t, arg);
 
     arg = xc_hypercall_buffer_alloc(xch, arg, sizeof(*arg));
@@ -571,13 +567,12 @@ int xc_watchdog(xc_interface *xch,
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_sched_op;
-    hypercall.arg[0] = (unsigned long)SCHEDOP_watchdog;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
     arg->id = id;
     arg->timeout = timeout;
 
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_sched_op,
+                   SCHEDOP_watchdog,
+                   HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -1356,7 +1351,6 @@ static inline int xc_hvm_param_deprecated_check(uint32_t param)
 
 int xc_hvm_param_set(xc_interface *handle, domid_t dom, uint32_t param, uint64_t value)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_param_t, arg);
     int rc = xc_hvm_param_deprecated_check(param);
 
@@ -1367,20 +1361,18 @@ int xc_hvm_param_set(xc_interface *handle, domid_t dom, uint32_t param, uint64_t
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_param;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
     arg->domid = dom;
     arg->index = param;
     arg->value = value;
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_param,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
     xc_hypercall_buffer_free(handle, arg);
     return rc;
 }
 
 int xc_hvm_param_get(xc_interface *handle, domid_t dom, uint32_t param, uint64_t *value)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_param_t, arg);
     int rc = xc_hvm_param_deprecated_check(param);
 
@@ -1391,12 +1383,11 @@ int xc_hvm_param_get(xc_interface *handle, domid_t dom, uint32_t param, uint64_t
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_get_param;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
     arg->domid = dom;
     arg->index = param;
-    rc = do_xen_hypercall(handle, &hypercall);
+    rc = xencall2(handle->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_get_param,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
     *value = arg->value;
     xc_hypercall_buffer_free(handle, arg);
     return rc;
@@ -1424,7 +1415,6 @@ int xc_hvm_create_ioreq_server(xc_interface *xch,
                                int handle_bufioreq,
                                ioservid_t *id)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_create_ioreq_server_t, arg);
     int rc;
 
@@ -1432,14 +1422,12 @@ int xc_hvm_create_ioreq_server(xc_interface *xch,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_create_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->handle_bufioreq = handle_bufioreq;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_create_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     *id = arg->id;
 
@@ -1454,7 +1442,6 @@ int xc_hvm_get_ioreq_server_info(xc_interface *xch,
                                  xen_pfn_t *bufioreq_pfn,
                                  evtchn_port_t *bufioreq_port)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_get_ioreq_server_info_t, arg);
     int rc;
 
@@ -1462,14 +1449,12 @@ int xc_hvm_get_ioreq_server_info(xc_interface *xch,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_get_ioreq_server_info;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_get_ioreq_server_info,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
     if ( rc != 0 )
         goto done;
 
@@ -1491,7 +1476,6 @@ int xc_hvm_map_io_range_to_ioreq_server(xc_interface *xch, domid_t domid,
                                         ioservid_t id, int is_mmio,
                                         uint64_t start, uint64_t end)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_io_range_t, arg);
     int rc;
 
@@ -1499,17 +1483,15 @@ int xc_hvm_map_io_range_to_ioreq_server(xc_interface *xch, domid_t domid,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_map_io_range_to_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
     arg->type = is_mmio ? HVMOP_IO_RANGE_MEMORY : HVMOP_IO_RANGE_PORT;
     arg->start = start;
     arg->end = end;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_map_io_range_to_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
@@ -1519,7 +1501,6 @@ int xc_hvm_unmap_io_range_from_ioreq_server(xc_interface *xch, domid_t domid,
                                             ioservid_t id, int is_mmio,
                                             uint64_t start, uint64_t end)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_io_range_t, arg);
     int rc;
 
@@ -1527,17 +1508,15 @@ int xc_hvm_unmap_io_range_from_ioreq_server(xc_interface *xch, domid_t domid,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_unmap_io_range_from_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
     arg->type = is_mmio ? HVMOP_IO_RANGE_MEMORY : HVMOP_IO_RANGE_PORT;
     arg->start = start;
     arg->end = end;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_unmap_io_range_from_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
@@ -1548,7 +1527,6 @@ int xc_hvm_map_pcidev_to_ioreq_server(xc_interface *xch, domid_t domid,
                                       uint8_t bus, uint8_t device,
                                       uint8_t function)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_io_range_t, arg);
     int rc;
 
@@ -1561,10 +1539,6 @@ int xc_hvm_map_pcidev_to_ioreq_server(xc_interface *xch, domid_t domid,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_map_io_range_to_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
     arg->type = HVMOP_IO_RANGE_PCI;
@@ -1578,7 +1552,9 @@ int xc_hvm_map_pcidev_to_ioreq_server(xc_interface *xch, domid_t domid,
                                            (uint64_t)device,
                                            (uint64_t)function);
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_map_io_range_to_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
@@ -1589,7 +1565,6 @@ int xc_hvm_unmap_pcidev_from_ioreq_server(xc_interface *xch, domid_t domid,
                                           uint8_t bus, uint8_t device,
                                           uint8_t function)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_io_range_t, arg);
     int rc;
 
@@ -1602,10 +1577,6 @@ int xc_hvm_unmap_pcidev_from_ioreq_server(xc_interface *xch, domid_t domid,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_unmap_io_range_from_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
     arg->type = HVMOP_IO_RANGE_PCI;
@@ -1614,7 +1585,9 @@ int xc_hvm_unmap_pcidev_from_ioreq_server(xc_interface *xch, domid_t domid,
                                            (uint64_t)device,
                                            (uint64_t)function);
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_unmap_io_range_from_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
@@ -1624,7 +1597,6 @@ int xc_hvm_destroy_ioreq_server(xc_interface *xch,
                                 domid_t domid,
                                 ioservid_t id)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_destroy_ioreq_server_t, arg);
     int rc;
 
@@ -1632,14 +1604,12 @@ int xc_hvm_destroy_ioreq_server(xc_interface *xch,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_destroy_ioreq_server;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_destroy_ioreq_server,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
@@ -1650,7 +1620,6 @@ int xc_hvm_set_ioreq_server_state(xc_interface *xch,
                                   ioservid_t id,
                                   int enabled)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_hvm_set_ioreq_server_state_t, arg);
     int rc;
 
@@ -1658,15 +1627,13 @@ int xc_hvm_set_ioreq_server_state(xc_interface *xch,
     if ( arg == NULL )
         return -1;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_ioreq_server_state;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = domid;
     arg->id = id;
     arg->enabled = !!enabled;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_ioreq_server_state,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
     return rc;
diff --git a/tools/libxc/xc_evtchn.c b/tools/libxc/xc_evtchn.c
index ae2fe1a..53f7605 100644
--- a/tools/libxc/xc_evtchn.c
+++ b/tools/libxc/xc_evtchn.c
@@ -25,7 +25,6 @@ static int do_evtchn_op(xc_interface *xch, int cmd, void *arg,
                         size_t arg_size, int silently_fail)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(arg, arg_size, XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( xc_hypercall_bounce_pre(xch, arg) )
@@ -34,11 +33,9 @@ static int do_evtchn_op(xc_interface *xch, int cmd, void *arg,
         goto out;
     }
 
-    hypercall.op     = __HYPERVISOR_event_channel_op;
-    hypercall.arg[0] = cmd;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
-    if ((ret = do_xen_hypercall(xch, &hypercall)) < 0 && !silently_fail)
+    ret = xencall2(xch->xcall, __HYPERVISOR_event_channel_op,
+                   cmd, HYPERCALL_BUFFER_AS_ARG(arg));
+    if ( ret < 0 && !silently_fail )
         ERROR("do_evtchn_op: HYPERVISOR_event_channel_op failed: %d", ret);
 
     xc_hypercall_bounce_post(xch, arg);
diff --git a/tools/libxc/xc_flask.c b/tools/libxc/xc_flask.c
index b533656..ec52b0f 100644
--- a/tools/libxc/xc_flask.c
+++ b/tools/libxc/xc_flask.c
@@ -37,7 +37,6 @@
 int xc_flask_op(xc_interface *xch, xen_flask_op_t *op)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(op, sizeof(*op), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     op->interface_version = XEN_FLASK_INTERFACE_VERSION;
@@ -48,10 +47,9 @@ int xc_flask_op(xc_interface *xch, xen_flask_op_t *op)
         goto out;
     }
 
-    hypercall.op     = __HYPERVISOR_xsm_op;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(op);
-
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall1(xch->xcall, __HYPERVISOR_xsm_op,
+                   HYPERCALL_BUFFER_AS_ARG(op));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             fprintf(stderr, "XSM operation failed!\n");
diff --git a/tools/libxc/xc_freebsd_osdep.c b/tools/libxc/xc_freebsd_osdep.c
index f6a2ccd..6b440ee 100644
--- a/tools/libxc/xc_freebsd_osdep.c
+++ b/tools/libxc/xc_freebsd_osdep.c
@@ -88,53 +88,6 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-/*------------------------ Privcmd hypercall interface -----------------------*/
-void *osdep_alloc_hypercall_buffer(xc_interface *xch, int npages)
-{
-    size_t size = npages * XC_PAGE_SIZE;
-    void *p;
-
-    /* Address returned by mmap is page aligned. */
-    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS,
-             -1, 0);
-    if (p == NULL)
-        return NULL;
-
-    /*
-     * Since FreeBSD doesn't have the MAP_LOCKED flag,
-     * lock memory using mlock.
-     */
-    if ( mlock(p, size) < 0 )
-    {
-        munmap(p, size);
-        return NULL;
-    }
-
-    return p;
-}
-
-void osdep_free_hypercall_buffer(xc_interface *xch, void *ptr, int npages)
-{
-
-    int saved_errno = errno;
-    /* Unlock pages */
-    munlock(ptr, npages * XC_PAGE_SIZE);
-
-    munmap(ptr, npages * XC_PAGE_SIZE);
-    /* We MUST propagate the hypercall errno, not unmap call's. */
-    errno = saved_errno;
-}
-
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
-{
-    int fd = xch->privcmdfd;
-    int ret;
-
-    ret = ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
-
-    return (ret == 0) ? hypercall->retval : ret;
-}
-
 /*----------------------- Privcmd foreign map interface ----------------------*/
 void *xc_map_foreign_bulk(xc_interface *xch,
                           uint32_t dom, int prot,
diff --git a/tools/libxc/xc_gnttab.c b/tools/libxc/xc_gnttab.c
index dd32aa2..af53fac 100644
--- a/tools/libxc/xc_gnttab.c
+++ b/tools/libxc/xc_gnttab.c
@@ -21,7 +21,6 @@
 int xc_gnttab_op(xc_interface *xch, int cmd, void * op, int op_size, int count)
 {
     int ret = 0;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(op, count * op_size, XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( xc_hypercall_bounce_pre(xch, op) )
@@ -30,12 +29,8 @@ int xc_gnttab_op(xc_interface *xch, int cmd, void * op, int op_size, int count)
         goto out1;
     }
 
-    hypercall.op = __HYPERVISOR_grant_table_op;
-    hypercall.arg[0] = cmd;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(op);
-    hypercall.arg[2] = count;
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall3(xch->xcall,  __HYPERVISOR_grant_table_op,
+                   cmd, HYPERCALL_BUFFER_AS_ARG(op), count);
 
     xc_hypercall_bounce_post(xch, op);
 
diff --git a/tools/libxc/xc_hcall_buf.c b/tools/libxc/xc_hcall_buf.c
index a0e66cf..a57895b 100644
--- a/tools/libxc/xc_hcall_buf.c
+++ b/tools/libxc/xc_hcall_buf.c
@@ -17,7 +17,6 @@
 
 #include <stdlib.h>
 #include <string.h>
-#include <pthread.h>
 
 #include "xc_private.h"
 #include "xg_private.h"
@@ -28,163 +27,38 @@ xc_hypercall_buffer_t XC__HYPERCALL_BUFFER_NAME(HYPERCALL_BUFFER_NULL) = {
     HYPERCALL_BUFFER_INIT_NO_BOUNCE
 };
 
-pthread_mutex_t hypercall_buffer_cache_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-static void hypercall_buffer_cache_lock(xc_interface *xch)
-{
-    int saved_errno = errno;
-    if ( xch->flags & XC_OPENFLAG_NON_REENTRANT )
-        return;
-    pthread_mutex_lock(&hypercall_buffer_cache_mutex);
-    /* Ignore pthread errors. */
-    errno = saved_errno;
-}
-
-static void hypercall_buffer_cache_unlock(xc_interface *xch)
-{
-    int saved_errno = errno;
-    if ( xch->flags & XC_OPENFLAG_NON_REENTRANT )
-        return;
-    pthread_mutex_unlock(&hypercall_buffer_cache_mutex);
-    /* Ignore pthread errors. */
-    errno = saved_errno;
-}
-
-static void *hypercall_buffer_cache_alloc(xc_interface *xch, int nr_pages)
-{
-    void *p = NULL;
-
-    hypercall_buffer_cache_lock(xch);
-
-    xch->hypercall_buffer_total_allocations++;
-    xch->hypercall_buffer_current_allocations++;
-    if ( xch->hypercall_buffer_current_allocations > xch->hypercall_buffer_maximum_allocations )
-        xch->hypercall_buffer_maximum_allocations = xch->hypercall_buffer_current_allocations;
-
-    if ( nr_pages > 1 )
-    {
-        xch->hypercall_buffer_cache_toobig++;
-    }
-    else if ( xch->hypercall_buffer_cache_nr > 0 )
-    {
-        p = xch->hypercall_buffer_cache[--xch->hypercall_buffer_cache_nr];
-        xch->hypercall_buffer_cache_hits++;
-    }
-    else
-    {
-        xch->hypercall_buffer_cache_misses++;
-    }
-
-    hypercall_buffer_cache_unlock(xch);
-
-    return p;
-}
-
-static int hypercall_buffer_cache_free(xc_interface *xch, void *p, int nr_pages)
-{
-    int rc = 0;
-
-    hypercall_buffer_cache_lock(xch);
-
-    xch->hypercall_buffer_total_releases++;
-    xch->hypercall_buffer_current_allocations--;
-
-    if ( nr_pages == 1 && xch->hypercall_buffer_cache_nr < HYPERCALL_BUFFER_CACHE_SIZE )
-    {
-        xch->hypercall_buffer_cache[xch->hypercall_buffer_cache_nr++] = p;
-        rc = 1;
-    }
-
-    hypercall_buffer_cache_unlock(xch);
-
-    return rc;
-}
-
-void xc__hypercall_buffer_cache_release(xc_interface *xch)
-{
-    void *p;
-
-    hypercall_buffer_cache_lock(xch);
-
-    DBGPRINTF("hypercall buffer: total allocations:%d total releases:%d",
-              xch->hypercall_buffer_total_allocations,
-              xch->hypercall_buffer_total_releases);
-    DBGPRINTF("hypercall buffer: current allocations:%d maximum allocations:%d",
-              xch->hypercall_buffer_current_allocations,
-              xch->hypercall_buffer_maximum_allocations);
-    DBGPRINTF("hypercall buffer: cache current size:%d",
-              xch->hypercall_buffer_cache_nr);
-    DBGPRINTF("hypercall buffer: cache hits:%d misses:%d toobig:%d",
-              xch->hypercall_buffer_cache_hits,
-              xch->hypercall_buffer_cache_misses,
-              xch->hypercall_buffer_cache_toobig);
-
-    while ( xch->hypercall_buffer_cache_nr > 0 )
-    {
-        p = xch->hypercall_buffer_cache[--xch->hypercall_buffer_cache_nr];
-        osdep_free_hypercall_buffer(xch, p, 1);
-    }
-
-    hypercall_buffer_cache_unlock(xch);
-}
-
 void *xc__hypercall_buffer_alloc_pages(xc_interface *xch, xc_hypercall_buffer_t *b, int nr_pages)
 {
-    void *p = hypercall_buffer_cache_alloc(xch, nr_pages);
-
-    if ( !p )
-        p = osdep_alloc_hypercall_buffer(xch, nr_pages);
+    void *p = xencall_alloc_buffer_pages(xch->xcall, nr_pages);
 
     if (!p)
         return NULL;
 
     b->hbuf = p;
 
-    memset(p, 0, nr_pages * PAGE_SIZE);
-
     return b->hbuf;
 }
 
 void xc__hypercall_buffer_free_pages(xc_interface *xch, xc_hypercall_buffer_t *b, int nr_pages)
 {
-    if ( b->hbuf == NULL )
-        return;
-
-    if ( !hypercall_buffer_cache_free(xch, b->hbuf, nr_pages) )
-        osdep_free_hypercall_buffer(xch, b->hbuf, nr_pages);
+    xencall_free_buffer_pages(xch->xcall, b->hbuf, nr_pages);
 }
 
-struct allocation_header {
-    int nr_pages;
-};
-
 void *xc__hypercall_buffer_alloc(xc_interface *xch, xc_hypercall_buffer_t *b, size_t size)
 {
-    size_t actual_size = ROUNDUP(size + sizeof(struct allocation_header), PAGE_SHIFT);
-    int nr_pages = actual_size >> PAGE_SHIFT;
-    struct allocation_header *hdr;
+    void *p = xencall_alloc_buffer(xch->xcall, size);
 
-    hdr = xc__hypercall_buffer_alloc_pages(xch, b, nr_pages);
-    if ( hdr == NULL )
+    if (!p)
         return NULL;
 
-    b->hbuf = (void *)(hdr+1);
+    b->hbuf = p;
 
-    hdr->nr_pages = nr_pages;
     return b->hbuf;
 }
 
 void xc__hypercall_buffer_free(xc_interface *xch, xc_hypercall_buffer_t *b)
 {
-    struct allocation_header *hdr;
-
-    if (b->hbuf == NULL)
-        return;
-
-    hdr = b->hbuf;
-    b->hbuf = --hdr;
-
-    xc__hypercall_buffer_free_pages(xch, b, hdr->nr_pages);
+    xencall_free_buffer(xch->xcall, b->hbuf);
 }
 
 int xc__hypercall_bounce_pre(xc_interface *xch, xc_hypercall_buffer_t *b)
diff --git a/tools/libxc/xc_kexec.c b/tools/libxc/xc_kexec.c
index a49cffb..1cceb5d 100644
--- a/tools/libxc/xc_kexec.c
+++ b/tools/libxc/xc_kexec.c
@@ -14,7 +14,6 @@
 
 int xc_kexec_exec(xc_interface *xch, int type)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_kexec_exec_t, exec);
     int ret = -1;
 
@@ -27,11 +26,9 @@ int xc_kexec_exec(xc_interface *xch, int type)
 
     exec->type = type;
 
-    hypercall.op = __HYPERVISOR_kexec_op;
-    hypercall.arg[0] = KEXEC_CMD_kexec;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(exec);
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_kexec_op,
+		   KEXEC_CMD_kexec,
+		   HYPERCALL_BUFFER_AS_ARG(exec));
 
 out:
     xc_hypercall_buffer_free(xch, exec);
@@ -42,7 +39,6 @@ out:
 int xc_kexec_get_range(xc_interface *xch, int range,  int nr,
                        uint64_t *size, uint64_t *start)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_kexec_range_t, get_range);
     int ret = -1;
 
@@ -56,11 +52,9 @@ int xc_kexec_get_range(xc_interface *xch, int range,  int nr,
     get_range->range = range;
     get_range->nr = nr;
 
-    hypercall.op = __HYPERVISOR_kexec_op;
-    hypercall.arg[0] = KEXEC_CMD_kexec_get_range;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(get_range);
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_kexec_op,
+		   KEXEC_CMD_kexec_get_range,
+		   HYPERCALL_BUFFER_AS_ARG(get_range));
 
     *size = get_range->size;
     *start = get_range->start;
@@ -76,7 +70,6 @@ int xc_kexec_load(xc_interface *xch, uint8_t type, uint16_t arch,
                   uint32_t nr_segments, xen_kexec_segment_t *segments)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(segments, sizeof(*segments) * nr_segments,
                              XC_HYPERCALL_BUFFER_BOUNCE_IN);
     DECLARE_HYPERCALL_BUFFER(xen_kexec_load_t, load);
@@ -99,11 +92,9 @@ int xc_kexec_load(xc_interface *xch, uint8_t type, uint16_t arch,
     load->nr_segments = nr_segments;
     set_xen_guest_handle(load->segments.h, segments);
 
-    hypercall.op = __HYPERVISOR_kexec_op;
-    hypercall.arg[0] = KEXEC_CMD_kexec_load;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(load);
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_kexec_op,
+		   KEXEC_CMD_kexec_load,
+		   HYPERCALL_BUFFER_AS_ARG(load));
 
 out:
     xc_hypercall_buffer_free(xch, load);
@@ -114,7 +105,6 @@ out:
 
 int xc_kexec_unload(xc_interface *xch, int type)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(xen_kexec_unload_t, unload);
     int ret = -1;
 
@@ -127,11 +117,9 @@ int xc_kexec_unload(xc_interface *xch, int type)
 
     unload->type = type;
 
-    hypercall.op = __HYPERVISOR_kexec_op;
-    hypercall.arg[0] = KEXEC_CMD_kexec_unload;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(unload);
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_kexec_op,
+		   KEXEC_CMD_kexec_unload,
+		   HYPERCALL_BUFFER_AS_ARG(unload));
 
 out:
     xc_hypercall_buffer_free(xch, unload);
diff --git a/tools/libxc/xc_linux_osdep.c b/tools/libxc/xc_linux_osdep.c
index 9f4c707..e68c495 100644
--- a/tools/libxc/xc_linux_osdep.c
+++ b/tools/libxc/xc_linux_osdep.c
@@ -91,55 +91,6 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-void *osdep_alloc_hypercall_buffer(xc_interface *xch, int npages)
-{
-    size_t size = npages * XC_PAGE_SIZE;
-    void *p;
-    int rc, saved_errno;
-
-    /* Address returned by mmap is page aligned. */
-    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_LOCKED, -1, 0);
-    if ( p == MAP_FAILED )
-    {
-        PERROR("xc_alloc_hypercall_buffer: mmap failed");
-        return NULL;
-    }
-
-    /* Do not copy the VMA to child process on fork. Avoid the page being COW
-        on hypercall. */
-    rc = madvise(p, npages * XC_PAGE_SIZE, MADV_DONTFORK);
-    if ( rc < 0 )
-    {
-        PERROR("xc_alloc_hypercall_buffer: madvise failed");
-        goto out;
-    }
-
-    return p;
-
-out:
-    saved_errno = errno;
-    (void)munmap(p, size);
-    errno = saved_errno;
-    return NULL;
-}
-
-void osdep_free_hypercall_buffer(xc_interface *xch, void *ptr, int npages)
-{
-    int saved_errno = errno;
-    /* Recover the VMA flags. Maybe it's not necessary */
-    madvise(ptr, npages * XC_PAGE_SIZE, MADV_DOFORK);
-
-    munmap(ptr, npages * XC_PAGE_SIZE);
-    /* We MUST propagate the hypercall errno, not unmap call's. */
-    errno = saved_errno;
-}
-
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
-{
-    int fd = xch->privcmdfd;
-    return ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
-}
-
 static int xc_map_foreign_batch_single(int fd, uint32_t dom,
                                        xen_pfn_t *mfn, unsigned long addr)
 {
diff --git a/tools/libxc/xc_minios.c b/tools/libxc/xc_minios.c
index 047e13b..e3c8241 100644
--- a/tools/libxc/xc_minios.c
+++ b/tools/libxc/xc_minios.c
@@ -61,38 +61,6 @@ void minios_interface_close_fd(int fd)
     files[fd].type = FTYPE_NONE;
 }
 
-void *osdep_alloc_hypercall_buffer(xc_interface *xch, int npages)
-{
-    return xc_memalign(xch, PAGE_SIZE, npages * PAGE_SIZE);
-}
-
-void osdep_free_hypercall_buffer(xc_interface *xch, void *ptr, int npages)
-{
-    free(ptr);
-}
-
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
-{
-    multicall_entry_t call;
-    int i, ret;
-
-    call.op = hypercall->op;
-    for (i = 0; i < ARRAY_SIZE(hypercall->arg); i++)
-	call.args[i] = hypercall->arg[i];
-
-    ret = HYPERVISOR_multicall(&call, 1);
-
-    if (ret < 0) {
-	errno = -ret;
-	return -1;
-    }
-    if ((long) call.result < 0) {
-        errno = - (long) call.result;
-        return -1;
-    }
-    return call.result;
-}
-
 void *xc_map_foreign_bulk(xc_interface *xch,
                           uint32_t dom, int prot,
                           const xen_pfn_t *arr, int *err, unsigned int num)
diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index c613545..124537b 100644
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -323,7 +323,6 @@ int xc_sched_id(xc_interface *xch,
 int xc_mca_op(xc_interface *xch, struct xen_mc *mc)
 {
     int ret = 0;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(mc, sizeof(*mc), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( xc_hypercall_bounce_pre(xch, mc) )
@@ -333,9 +332,9 @@ int xc_mca_op(xc_interface *xch, struct xen_mc *mc)
     }
     mc->interface_version = XEN_MCA_INTERFACE_VERSION;
 
-    hypercall.op = __HYPERVISOR_mca;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(mc);
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall1(xch->xcall, __HYPERVISOR_mca,
+                   HYPERCALL_BUFFER_AS_ARG(mc));
+
     xc_hypercall_bounce_post(xch, mc);
     return ret;
 }
@@ -471,7 +470,6 @@ int xc_hvm_set_pci_intx_level(
     uint8_t domain, uint8_t bus, uint8_t device, uint8_t intx,
     unsigned int level)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_set_pci_intx_level, arg);
     int rc;
 
@@ -482,10 +480,6 @@ int xc_hvm_set_pci_intx_level(
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_pci_intx_level;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid  = dom;
     arg->domain = domain;
     arg->bus    = bus;
@@ -493,7 +487,9 @@ int xc_hvm_set_pci_intx_level(
     arg->intx   = intx;
     arg->level  = level;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_pci_intx_level,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -505,7 +501,6 @@ int xc_hvm_set_isa_irq_level(
     uint8_t isa_irq,
     unsigned int level)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_set_isa_irq_level, arg);
     int rc;
 
@@ -516,15 +511,13 @@ int xc_hvm_set_isa_irq_level(
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_isa_irq_level;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid   = dom;
     arg->isa_irq = isa_irq;
     arg->level   = level;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_isa_irq_level,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -534,7 +527,6 @@ int xc_hvm_set_isa_irq_level(
 int xc_hvm_set_pci_link_route(
     xc_interface *xch, domid_t dom, uint8_t link, uint8_t isa_irq)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_set_pci_link_route, arg);
     int rc;
 
@@ -545,15 +537,13 @@ int xc_hvm_set_pci_link_route(
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_pci_link_route;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid   = dom;
     arg->link    = link;
     arg->isa_irq = isa_irq;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_pci_link_route,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -563,7 +553,6 @@ int xc_hvm_set_pci_link_route(
 int xc_hvm_inject_msi(
     xc_interface *xch, domid_t dom, uint64_t addr, uint32_t data)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_inject_msi, arg);
     int rc;
 
@@ -574,15 +563,13 @@ int xc_hvm_inject_msi(
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_inject_msi;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid = dom;
     arg->addr  = addr;
     arg->data  = data;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_inject_msi,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -594,7 +581,6 @@ int xc_hvm_track_dirty_vram(
     uint64_t first_pfn, uint64_t nr,
     unsigned long *dirty_bitmap)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(dirty_bitmap, (nr+7) / 8, XC_HYPERCALL_BUFFER_BOUNCE_OUT);
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_track_dirty_vram, arg);
     int rc;
@@ -607,16 +593,14 @@ int xc_hvm_track_dirty_vram(
         goto out;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_track_dirty_vram;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid     = dom;
     arg->first_pfn = first_pfn;
     arg->nr        = nr;
     set_xen_guest_handle(arg->dirty_bitmap, dirty_bitmap);
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_track_dirty_vram,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
 out:
     xc_hypercall_buffer_free(xch, arg);
@@ -627,7 +611,6 @@ out:
 int xc_hvm_modified_memory(
     xc_interface *xch, domid_t dom, uint64_t first_pfn, uint64_t nr)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_modified_memory, arg);
     int rc;
 
@@ -638,15 +621,13 @@ int xc_hvm_modified_memory(
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_modified_memory;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
     arg->domid     = dom;
     arg->first_pfn = first_pfn;
     arg->nr        = nr;
 
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_modified_memory,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -656,7 +637,6 @@ int xc_hvm_modified_memory(
 int xc_hvm_set_mem_type(
     xc_interface *xch, domid_t dom, hvmmem_type_t mem_type, uint64_t first_pfn, uint64_t nr)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_set_mem_type, arg);
     int rc;
 
@@ -672,11 +652,9 @@ int xc_hvm_set_mem_type(
     arg->first_pfn    = first_pfn;
     arg->nr           = nr;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_set_mem_type;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_set_mem_type,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
@@ -688,7 +666,6 @@ int xc_hvm_inject_trap(
     uint32_t type, uint32_t error_code, uint32_t insn_len,
     uint64_t cr2)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER(struct xen_hvm_inject_trap, arg);
     int rc;
 
@@ -707,11 +684,9 @@ int xc_hvm_inject_trap(
     arg->insn_len    = insn_len;
     arg->cr2         = cr2;
 
-    hypercall.op     = __HYPERVISOR_hvm_op;
-    hypercall.arg[0] = HVMOP_inject_trap;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
-    rc = do_xen_hypercall(xch, &hypercall);
+    rc = xencall2(xch->xcall, __HYPERVISOR_hvm_op,
+                  HVMOP_inject_trap,
+                  HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_buffer_free(xch, arg);
 
diff --git a/tools/libxc/xc_netbsd.c b/tools/libxc/xc_netbsd.c
index 9abb3b6..5e3b343 100644
--- a/tools/libxc/xc_netbsd.c
+++ b/tools/libxc/xc_netbsd.c
@@ -67,46 +67,6 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-void *osdep_alloc_hypercall_buffer(xc_interface *xch, int npages)
-{
-    size_t size = npages * XC_PAGE_SIZE;
-    void *p;
-
-    p = xc_memalign(xch, XC_PAGE_SIZE, size);
-    if (!p)
-        return NULL;
-
-    if ( mlock(p, size) < 0 )
-    {
-        free(p);
-        return NULL;
-    }
-    return p;
-}
-
-void osdep_free_hypercall_buffer(xc_interface *xch, void *ptr, int npages)
-{
-    (void) munlock(ptr, npages * XC_PAGE_SIZE);
-    free(ptr);
-}
-
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
-{
-    int fd = xch->privcmdfd;
-    int error = ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
-
-    /*
-     * Since NetBSD ioctl can only return 0 on success or < 0 on
-     * error, if we want to return a value from ioctl we should
-     * do so by setting hypercall->retval, to mimic Linux ioctl
-     * implementation.
-     */
-    if (error < 0)
-        return error;
-    else
-        return hypercall->retval;
-}
-
 void *xc_map_foreign_bulk(xc_interface *xch,
                           uint32_t dom, int prot,
                           const xen_pfn_t *arr, int *err, unsigned int num)
diff --git a/tools/libxc/xc_private.c b/tools/libxc/xc_private.c
index de5873e..ca4c17a 100644
--- a/tools/libxc/xc_private.c
+++ b/tools/libxc/xc_private.c
@@ -39,16 +39,6 @@ struct xc_interface_core *xc_interface_open(xentoollog_logger *logger,
     xch->error_handler   = logger;           xch->error_handler_tofree   = 0;
     xch->dombuild_logger = dombuild_logger;  xch->dombuild_logger_tofree = 0;
 
-    xch->hypercall_buffer_cache_nr = 0;
-
-    xch->hypercall_buffer_total_allocations = 0;
-    xch->hypercall_buffer_total_releases = 0;
-    xch->hypercall_buffer_current_allocations = 0;
-    xch->hypercall_buffer_maximum_allocations = 0;
-    xch->hypercall_buffer_cache_hits = 0;
-    xch->hypercall_buffer_cache_misses = 0;
-    xch->hypercall_buffer_cache_toobig = 0;
-
     if (!xch->error_handler) {
         xch->error_handler = xch->error_handler_tofree =
             (xentoollog_logger*)
@@ -65,14 +55,22 @@ struct xc_interface_core *xc_interface_open(xentoollog_logger *logger,
     }
     *xch = xch_buf;
 
-    if (!(open_flags & XC_OPENFLAG_DUMMY)) {
-        if ( osdep_privcmd_open(xch) < 0 )
-            goto err;
-    }
+    if (open_flags & XC_OPENFLAG_DUMMY)
+        return xch; /* We are done */
+
+    if ( osdep_privcmd_open(xch) < 0 )
+        goto err;
+
+    xch->xcall = xencall_open(xch->error_handler,
+        open_flags & XC_OPENFLAG_NON_REENTRANT ? XENCALL_OPENFLAG_NON_REENTRANT : 0U);
+
+    if ( xch->xcall == NULL )
+        goto err;
 
     return xch;
 
  err:
+    osdep_privcmd_close(xch);
     xtl_logger_destroy(xch->error_handler_tofree);
     if (xch != &xch_buf) free(xch);
     return NULL;
@@ -85,11 +83,12 @@ int xc_interface_close(xc_interface *xch)
     if (!xch)
         return 0;
 
+    rc = xencall_close(xch->xcall);
+    if (rc) PERROR("Could not close xencall interface");
+
     rc = osdep_privcmd_close(xch);
     if (rc) PERROR("Could not close hypervisor interface");
 
-    xc__hypercall_buffer_cache_release(xch);
-
     xtl_logger_destroy(xch->dombuild_logger_tofree);
     xtl_logger_destroy(xch->error_handler_tofree);
 
@@ -228,7 +227,6 @@ int xc_mmuext_op(
     unsigned int nr_ops,
     domid_t dom)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(op, nr_ops*sizeof(*op), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
     long ret = -1;
 
@@ -238,13 +236,9 @@ int xc_mmuext_op(
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_mmuext_op;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(op);
-    hypercall.arg[1] = (unsigned long)nr_ops;
-    hypercall.arg[2] = (unsigned long)0;
-    hypercall.arg[3] = (unsigned long)dom;
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall4(xch->xcall, __HYPERVISOR_mmuext_op,
+                   HYPERCALL_BUFFER_AS_ARG(op),
+                   nr_ops, 0, dom);
 
     xc_hypercall_bounce_post(xch, op);
 
@@ -254,8 +248,7 @@ int xc_mmuext_op(
 
 static int flush_mmu_updates(xc_interface *xch, struct xc_mmu *mmu)
 {
-    int err = 0;
-    DECLARE_HYPERCALL;
+    int rc, err = 0;
     DECLARE_NAMED_HYPERCALL_BOUNCE(updates, mmu->updates, mmu->idx*sizeof(*mmu->updates), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( mmu->idx == 0 )
@@ -268,13 +261,10 @@ static int flush_mmu_updates(xc_interface *xch, struct xc_mmu *mmu)
         goto out;
     }
 
-    hypercall.op     = __HYPERVISOR_mmu_update;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(updates);
-    hypercall.arg[1] = (unsigned long)mmu->idx;
-    hypercall.arg[2] = 0;
-    hypercall.arg[3] = mmu->subject;
-
-    if ( do_xen_hypercall(xch, &hypercall) < 0 )
+    rc = xencall4(xch->xcall, __HYPERVISOR_mmu_update,
+                  HYPERCALL_BUFFER_AS_ARG(updates),
+                  mmu->idx, 0, mmu->subject);
+    if ( rc < 0 )
     {
         ERROR("Failure when submitting mmu updates");
         err = 1;
@@ -317,7 +307,6 @@ int xc_flush_mmu_updates(xc_interface *xch, struct xc_mmu *mmu)
 
 long do_memory_op(xc_interface *xch, int cmd, void *arg, size_t len)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(arg, len, XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
     long ret = -1;
 
@@ -327,11 +316,8 @@ long do_memory_op(xc_interface *xch, int cmd, void *arg, size_t len)
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_memory_op;
-    hypercall.arg[0] = (unsigned long) cmd;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(arg);
-
-    ret = do_xen_hypercall(xch, &hypercall);
+    ret = xencall2(xch->xcall, __HYPERVISOR_memory_op,
+                   cmd, HYPERCALL_BUFFER_AS_ARG(arg));
 
     xc_hypercall_bounce_post(xch, arg);
  out1:
diff --git a/tools/libxc/xc_private.h b/tools/libxc/xc_private.h
index 30157cf..c93df7f 100644
--- a/tools/libxc/xc_private.h
+++ b/tools/libxc/xc_private.h
@@ -30,6 +30,7 @@
 
 #include "_paths.h"
 #include "xenctrl.h"
+#include <xencall.h>
 
 #include <xen/sys/privcmd.h>
 
@@ -53,7 +54,6 @@ struct iovec {
 #include <sys/uio.h>
 #endif
 
-#define DECLARE_HYPERCALL privcmd_hypercall_t hypercall
 #define DECLARE_DOMCTL struct xen_domctl domctl
 #define DECLARE_SYSCTL struct xen_sysctl sysctl
 #define DECLARE_PHYSDEV_OP struct physdev_op physdev_op
@@ -94,29 +94,11 @@ struct xc_interface_core {
     FILE *dombuild_logger_file;
     const char *currently_progress_reporting;
 
-    /*
-     * A simple cache of unused, single page, hypercall buffers
-     *
-     * Protected by a global lock.
-     */
-#define HYPERCALL_BUFFER_CACHE_SIZE 4
-    int hypercall_buffer_cache_nr;
-    void *hypercall_buffer_cache[HYPERCALL_BUFFER_CACHE_SIZE];
-
-    /*
-     * Hypercall buffer statistics. All protected by the global
-     * hypercall_buffer_cache lock.
-     */
-    int hypercall_buffer_total_allocations;
-    int hypercall_buffer_total_releases;
-    int hypercall_buffer_current_allocations;
-    int hypercall_buffer_maximum_allocations;
-    int hypercall_buffer_cache_hits;
-    int hypercall_buffer_cache_misses;
-    int hypercall_buffer_cache_toobig;
-
     /* Privcmd interface */
     int privcmdfd;
+
+    /* Hypercall interface */
+    xencall_handle *xcall;
 };
 
 int osdep_privcmd_open(xc_interface *xch);
@@ -232,24 +214,16 @@ void xc__hypercall_buffer_cache_release(xc_interface *xch);
  * Hypercall interfaces.
  */
 
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall);
-
 static inline int do_xen_version(xc_interface *xch, int cmd, xc_hypercall_buffer_t *dest)
 {
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER_ARGUMENT(dest);
-
-    hypercall.op     = __HYPERVISOR_xen_version;
-    hypercall.arg[0] = (unsigned long) cmd;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(dest);
-
-    return do_xen_hypercall(xch, &hypercall);
+    return xencall2(xch->xcall, __HYPERVISOR_xen_version,
+                    cmd, HYPERCALL_BUFFER_AS_ARG(dest));
 }
 
 static inline int do_physdev_op(xc_interface *xch, int cmd, void *op, size_t len)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(op, len, XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( xc_hypercall_bounce_pre(xch, op) )
@@ -258,11 +232,9 @@ static inline int do_physdev_op(xc_interface *xch, int cmd, void *op, size_t len
         goto out1;
     }
 
-    hypercall.op = __HYPERVISOR_physdev_op;
-    hypercall.arg[0] = (unsigned long) cmd;
-    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(op);
-
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall2(xch->xcall, __HYPERVISOR_physdev_op,
+                   cmd, HYPERCALL_BUFFER_AS_ARG(op));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("physdev operation failed -- need to"
@@ -277,7 +249,6 @@ out1:
 static inline int do_domctl(xc_interface *xch, struct xen_domctl *domctl)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(domctl, sizeof(*domctl), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     domctl->interface_version = XEN_DOMCTL_INTERFACE_VERSION;
@@ -288,10 +259,9 @@ static inline int do_domctl(xc_interface *xch, struct xen_domctl *domctl)
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_domctl;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(domctl);
-
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall1(xch->xcall, __HYPERVISOR_domctl,
+                   HYPERCALL_BUFFER_AS_ARG(domctl));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("domctl operation failed -- need to"
@@ -306,7 +276,6 @@ static inline int do_domctl(xc_interface *xch, struct xen_domctl *domctl)
 static inline int do_sysctl(xc_interface *xch, struct xen_sysctl *sysctl)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(sysctl, sizeof(*sysctl), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     sysctl->interface_version = XEN_SYSCTL_INTERFACE_VERSION;
@@ -317,9 +286,9 @@ static inline int do_sysctl(xc_interface *xch, struct xen_sysctl *sysctl)
         goto out1;
     }
 
-    hypercall.op     = __HYPERVISOR_sysctl;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(sysctl);
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall1(xch->xcall, __HYPERVISOR_sysctl,
+                   HYPERCALL_BUFFER_AS_ARG(sysctl));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("sysctl operation failed -- need to"
@@ -335,7 +304,6 @@ static inline int do_platform_op(xc_interface *xch,
                                  struct xen_platform_op *platform_op)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(platform_op, sizeof(*platform_op),
                              XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
@@ -347,9 +315,9 @@ static inline int do_platform_op(xc_interface *xch,
         return -1;
     }
 
-    hypercall.op     = __HYPERVISOR_platform_op;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(platform_op);
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall1(xch->xcall, __HYPERVISOR_platform_op,
+                   HYPERCALL_BUFFER_AS_ARG(platform_op));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("platform operation failed -- need to"
@@ -365,13 +333,11 @@ static inline int do_multicall_op(xc_interface *xch,
                                   uint32_t nr_calls)
 {
     int ret = -1;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BUFFER_ARGUMENT(call_list);
 
-    hypercall.op     = __HYPERVISOR_multicall;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(call_list);
-    hypercall.arg[1] = nr_calls;
-    if ( (ret = do_xen_hypercall(xch, &hypercall)) < 0 )
+    ret = xencall2(xch->xcall, __HYPERVISOR_multicall,
+                   HYPERCALL_BUFFER_AS_ARG(call_list), nr_calls);
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("multicall operation failed -- need to"
diff --git a/tools/libxc/xc_solaris.c b/tools/libxc/xc_solaris.c
index 6f84b82..18622fa 100644
--- a/tools/libxc/xc_solaris.c
+++ b/tools/libxc/xc_solaris.c
@@ -67,22 +67,6 @@ int osdep_privcmd_close(xc_interface *xch)
     return close(fd);
 }
 
-void *osdep_alloc_hypercall_buffer(xc_interface *xch, int npages)
-{
-    return xc_memalign(xch, XC_PAGE_SIZE, npages * XC_PAGE_SIZE);
-}
-
-static void osdep_free_hypercall_buffer(xc_interface *xch, void *ptr, int npages)
-{
-    free(ptr);
-}
-
-int do_xen_hypercall(xc_interface *xch, privcmd_hypercall_t *hypercall)
-{
-    int fd = xch->privcmdfd;
-    return ioctl(fd, IOCTL_PRIVCMD_HYPERCALL, hypercall);
-}
-
 void *xc_map_foreign_batch(xc_interface *xch,
                           uint32_t dom, int prot,
                           xen_pfn_t *arr, int num)
diff --git a/tools/libxc/xc_tmem.c b/tools/libxc/xc_tmem.c
index 8f4c0cc..4e5c278 100644
--- a/tools/libxc/xc_tmem.c
+++ b/tools/libxc/xc_tmem.c
@@ -23,7 +23,6 @@
 static int do_tmem_op(xc_interface *xch, tmem_op_t *op)
 {
     int ret;
-    DECLARE_HYPERCALL;
     DECLARE_HYPERCALL_BOUNCE(op, sizeof(*op), XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
 
     if ( xc_hypercall_bounce_pre(xch, op) )
@@ -32,9 +31,9 @@ static int do_tmem_op(xc_interface *xch, tmem_op_t *op)
         return -EFAULT;
     }
 
-    hypercall.op = __HYPERVISOR_tmem_op;
-    hypercall.arg[0] = HYPERCALL_BUFFER_AS_ARG(op);
-    if ((ret = do_xen_hypercall(xch, &hypercall)) < 0)
+    ret = xencall1(xch->xcall, __HYPERVISOR_tmem_op,
+                   HYPERCALL_BUFFER_AS_ARG(op));
+    if ( ret < 0 )
     {
         if ( errno == EACCES )
             DPRINTF("tmem operation failed -- need to"
diff --git a/tools/misc/Makefile b/tools/misc/Makefile
index cf6a475..a2ef0ec 100644
--- a/tools/misc/Makefile
+++ b/tools/misc/Makefile
@@ -87,12 +87,12 @@ xenlockprof: xenlockprof.o
 	$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS_libxenctrl) $(APPEND_LDFLAGS)
 
 # xen-hptool incorrectly uses libxc internals
-xen-hptool.o: CFLAGS += -I$(XEN_ROOT)/tools/libxc
+xen-hptool.o: CFLAGS += -I$(XEN_ROOT)/tools/libxc $(CFLAGS_libxencall)
 xen-hptool: xen-hptool.o
 	$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS_libxenevtchn) $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(LDLIBS_libxenstore) $(APPEND_LDFLAGS)
 
 # xen-mfndump incorrectly uses libxc internals
-xen-mfndump.o: CFLAGS += -I$(XEN_ROOT)/tools/libxc
+xen-mfndump.o: CFLAGS += -I$(XEN_ROOT)/tools/libxc $(CFLAGS_libxencall)
 xen-mfndump: xen-mfndump.o
 	$(CC) $(LDFLAGS) -o $@ $< $(LDLIBS_libxenevtchn) $(LDLIBS_libxenctrl) $(LDLIBS_libxenguest) $(APPEND_LDFLAGS)
 
diff --git a/tools/xcutils/Makefile b/tools/xcutils/Makefile
index 2d1f112..e127af8 100644
--- a/tools/xcutils/Makefile
+++ b/tools/xcutils/Makefile
@@ -16,7 +16,7 @@ PROGRAMS = readnotes lsevtchn
 CFLAGS += -Werror
 
 # incorrectly uses libxc internals
-CFLAGS_readnotes.o  := $(CFLAGS_libxenevtchn) $(CFLAGS_libxenctrl) $(CFLAGS_libxenguest) -I$(XEN_ROOT)/tools/libxc
+CFLAGS_readnotes.o  := $(CFLAGS_libxenevtchn) $(CFLAGS_libxenctrl) $(CFLAGS_libxenguest) -I$(XEN_ROOT)/tools/libxc $(CFLAGS_libxencall)
 CFLAGS_lsevtchn.o   := $(CFLAGS_libxenevtchn) $(CFLAGS_libxenctrl)
 
 .PHONY: all
diff --git a/tools/xenpaging/Makefile b/tools/xenpaging/Makefile
index d491867..64876b3 100644
--- a/tools/xenpaging/Makefile
+++ b/tools/xenpaging/Makefile
@@ -2,7 +2,7 @@ XEN_ROOT=$(CURDIR)/../..
 include $(XEN_ROOT)/tools/Rules.mk
 
 # xenpaging.c and file_ops.c incorrectly use libxc internals
-CFLAGS += $(CFLAGS_libxentoollog) $(CFLAGS_libxenevtchn) $(CFLAGS_libxenctrl) $(CFLAGS_libxenstore) $(PTHREAD_CFLAGS) -I$(XEN_ROOT)/tools/libxc
+CFLAGS += $(CFLAGS_libxentoollog) $(CFLAGS_libxenevtchn) $(CFLAGS_libxenctrl) $(CFLAGS_libxenstore) $(PTHREAD_CFLAGS) -I$(XEN_ROOT)/tools/libxc $(CFLAGS_libxencall)
 LDLIBS += $(LDLIBS_libxentoollog) $(LDLIBS_libxenevtchn) $(LDLIBS_libxenctrl) $(LDLIBS_libxenstore) $(PTHREAD_LIBS)
 LDFLAGS += $(PTHREAD_LDFLAGS)
 
