[Qemu-devel] [PATCH V11 03/15] xen: Support new libxc calls from xen unstable.

[anthony.perard@citrix.com]

From: Anthony PERARD <anthony.perard@citrix.com>

This patch updates the libxenctrl calls in Qemu to use the new interface,
otherwise Qemu wouldn't be able to build against new versions of the
library.

We check libxenctrl version in configure, from Xen 3.3.0 to Xen
unstable.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
 configure            |   67 ++++++++++++++++++++++++++++++++++++++++++++++++-
 hw/xen_backend.c     |   21 ++++++++-------
 hw/xen_backend.h     |    6 ++--
 hw/xen_common.h      |   64 +++++++++++++++++++++++++++++++++++++----------
 hw/xen_disk.c        |    4 +-
 hw/xen_domainbuild.c |    3 +-
 6 files changed, 133 insertions(+), 32 deletions(-)

diff --git a/configure b/configure
index 3036faf..a84d974 100755
--- a/configure
+++ b/configure
@@ -126,6 +126,7 @@ vnc_jpeg=""
 vnc_png=""
 vnc_thread="no"
 xen=""
+xen_ctrl_version=""
 linux_aio=""
 attr=""
 vhost_net=""
@@ -1147,20 +1148,81 @@ fi
 
 if test "$xen" != "no" ; then
   xen_libs="-lxenstore -lxenctrl -lxenguest"
+
+  # Xen unstable
   cat > $TMPC <<EOF
 #include <xenctrl.h>
 #include <xs.h>
-int main(void) { xs_daemon_open(); xc_interface_open(); return 0; }
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xc_interface *xc;
+  xs_daemon_open();
+  xc = xc_interface_open(0, 0, 0);
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  xc_gnttab_open(NULL, 0);
+  return 0;
+}
 EOF
   if compile_prog "" "$xen_libs" ; then
+    xen_ctrl_version=410
     xen=yes
-    libs_softmmu="$xen_libs $libs_softmmu"
+
+  # Xen 4.0.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+#include <stdint.h>
+#include <xen/hvm/hvm_info_table.h>
+#if !defined(HVM_MAX_VCPUS)
+# error HVM_MAX_VCPUS not defined
+#endif
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=400
+    xen=yes
+
+  # Xen 3.3.0, 3.4.0
+  elif (
+      cat > $TMPC <<EOF
+#include <xenctrl.h>
+#include <xs.h>
+int main(void) {
+  xs_daemon_open();
+  xc_interface_open();
+  xc_gnttab_open();
+  xc_hvm_set_mem_type(0, 0, HVMMEM_ram_ro, 0, 0);
+  return 0;
+}
+EOF
+      compile_prog "" "$xen_libs"
+    ) ; then
+    xen_ctrl_version=330
+    xen=yes
+
+  # Xen not found or unsupported
   else
     if test "$xen" = "yes" ; then
       feature_not_found "xen"
     fi
     xen=no
   fi
+
+  if test "$xen" = yes; then
+    libs_softmmu="$xen_libs $libs_softmmu"
+  fi
 fi
 
 ##########################################
@@ -2755,6 +2817,7 @@ if test "$bluez" = "yes" ; then
 fi
 if test "$xen" = "yes" ; then
   echo "CONFIG_XEN=y" >> $config_host_mak
+  echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
 fi
 if test "$io_thread" = "yes" ; then
   echo "CONFIG_IOTHREAD=y" >> $config_host_mak
diff --git a/hw/xen_backend.c b/hw/xen_backend.c
index 9f4ec4b..3907b83 100644
--- a/hw/xen_backend.c
+++ b/hw/xen_backend.c
@@ -43,7 +43,8 @@
 /* ------------------------------------------------------------- */
 
 /* public */
-int xen_xc;
+XenXC xen_xc = XC_HANDLER_INITIAL_VALUE;
+XenGnttab xen_xcg = XC_HANDLER_INITIAL_VALUE;
 struct xs_handle *xenstore = NULL;
 const char *xen_protocol;
 
@@ -214,8 +215,8 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
     xendev->debug      = debug;
     xendev->local_port = -1;
 
-    xendev->evtchndev = xc_evtchn_open();
-    if (xendev->evtchndev < 0) {
+    xendev->evtchndev = xc_evtchn_open(NULL, 0);
+    if (xendev->evtchndev == XC_HANDLER_INITIAL_VALUE) {
         xen_be_printf(NULL, 0, "can't open evtchn device\n");
         qemu_free(xendev);
         return NULL;
@@ -223,15 +224,15 @@ static struct XenDevice *xen_be_get_xendev(const char *type, int dom, int dev,
     fcntl(xc_evtchn_fd(xendev->evtchndev), F_SETFD, FD_CLOEXEC);
 
     if (ops->flags & DEVOPS_FLAG_NEED_GNTDEV) {
-        xendev->gnttabdev = xc_gnttab_open();
-        if (xendev->gnttabdev < 0) {
+        xendev->gnttabdev = xc_gnttab_open(NULL, 0);
+        if (xendev->gnttabdev == XC_HANDLER_INITIAL_VALUE) {
             xen_be_printf(NULL, 0, "can't open gnttab device\n");
             xc_evtchn_close(xendev->evtchndev);
             qemu_free(xendev);
             return NULL;
         }
     } else {
-        xendev->gnttabdev = -1;
+        xendev->gnttabdev = XC_HANDLER_INITIAL_VALUE;
     }
 
     QTAILQ_INSERT_TAIL(&xendevs, xendev, next);
@@ -277,10 +278,10 @@ static struct XenDevice *xen_be_del_xendev(int dom, int dev)
             qemu_free(xendev->fe);
         }
 
-        if (xendev->evtchndev >= 0) {
+        if (xendev->evtchndev != XC_HANDLER_INITIAL_VALUE) {
             xc_evtchn_close(xendev->evtchndev);
         }
-        if (xendev->gnttabdev >= 0) {
+        if (xendev->gnttabdev != XC_HANDLER_INITIAL_VALUE) {
             xc_gnttab_close(xendev->gnttabdev);
         }
 
@@ -664,8 +665,8 @@ int xen_be_init(void)
         goto err;
     }
 
-    xen_xc = xc_interface_open();
-    if (xen_xc == -1) {
+    xen_xc = xc_interface_open(0, 0, 0);
+    if (xen_xc == XC_HANDLER_INITIAL_VALUE) {
         xen_be_printf(NULL, 0, "can't open xen interface\n");
         goto err;
     }
diff --git a/hw/xen_backend.h b/hw/xen_backend.h
index 1b428e3..6401c85 100644
--- a/hw/xen_backend.h
+++ b/hw/xen_backend.h
@@ -45,8 +45,8 @@ struct XenDevice {
     int                remote_port;
     int                local_port;
 
-    int                evtchndev;
-    int                gnttabdev;
+    XenEvtchn          evtchndev;
+    XenGnttab          gnttabdev;
 
     struct XenDevOps   *ops;
     QTAILQ_ENTRY(XenDevice) next;
@@ -55,7 +55,7 @@ struct XenDevice {
 /* ------------------------------------------------------------- */
 
 /* variables */
-extern int xen_xc;
+extern XenXC xen_xc;
 extern struct xs_handle *xenstore;
 extern const char *xen_protocol;
 
diff --git a/hw/xen_common.h b/hw/xen_common.h
index 8a55b44..7e123ec 100644
--- a/hw/xen_common.h
+++ b/hw/xen_common.h
@@ -1,6 +1,8 @@
 #ifndef QEMU_HW_XEN_COMMON_H
 #define QEMU_HW_XEN_COMMON_H 1
 
+#include "config-host.h"
+
 #include <stddef.h>
 #include <inttypes.h>
 
@@ -13,22 +15,56 @@
 #include "qemu-queue.h"
 
 /*
- * tweaks needed to build with different xen versions
- *  0x00030205 -> 3.1.0
- *  0x00030207 -> 3.2.0
- *  0x00030208 -> unstable
+ * We don't support Xen prior to 3.3.0.
  */
-#include <xen/xen-compat.h>
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030205
-# define evtchn_port_or_error_t int
-#endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030207
-# define xc_map_foreign_pages xc_map_foreign_batch
+
+/* Xen before 4.0 */
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 400
+static inline void *xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
+                                        xen_pfn_t *arr, int *err,
+                                        unsigned int num)
+{
+    return xc_map_foreign_batch(xc_handle, dom, prot, arr, num);
+}
 #endif
-#if __XEN_LATEST_INTERFACE_VERSION__ < 0x00030208
-# define xen_mb()  mb()
-# define xen_rmb() rmb()
-# define xen_wmb() wmb()
+
+
+/* Xen before 4.1 */
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 410
+
+typedef int XenXC;
+typedef int XenEvtchn;
+typedef int XenGnttab;
+
+#  define XC_INTERFACE_FMT "%i"
+#  define XC_HANDLER_INITIAL_VALUE    -1
+
+#  define xc_interface_open(logger, dombuild_logger, open_flags) \
+    xc_interface_open()
+#  define xc_evtchn_open(logger, open_flags) xc_evtchn_open()
+#  define xc_gnttab_open(logger, open_flags) xc_gnttab_open()
+
+static inline int xc_fd(int xen_xc)
+{
+    return xen_xc;
+}
+
+
+/* Xen 4.1 */
+#else
+
+typedef xc_interface *XenXC;
+typedef xc_evtchn *XenEvtchn;
+typedef xc_gnttab *XenGnttab;
+
+#  define XC_INTERFACE_FMT "%p"
+#  define XC_HANDLER_INITIAL_VALUE    NULL
+
+/* FIXME There is now way to have the xen fd */
+static inline int xc_fd(xc_interface *xen_xc)
+{
+    return -1;
+}
 #endif
 
 #endif /* QEMU_HW_XEN_COMMON_H */
diff --git a/hw/xen_disk.c b/hw/xen_disk.c
index 403c55f..07b8ec4 100644
--- a/hw/xen_disk.c
+++ b/hw/xen_disk.c
@@ -242,7 +242,7 @@ err:
 
 static void ioreq_unmap(struct ioreq *ioreq)
 {
-    int gnt = ioreq->blkdev->xendev.gnttabdev;
+    XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
     int i;
 
     if (ioreq->v.niov == 0) {
@@ -275,7 +275,7 @@ static void ioreq_unmap(struct ioreq *ioreq)
 
 static int ioreq_map(struct ioreq *ioreq)
 {
-    int gnt = ioreq->blkdev->xendev.gnttabdev;
+    XenGnttab gnt = ioreq->blkdev->xendev.gnttabdev;
     int i;
 
     if (ioreq->v.niov == 0) {
diff --git a/hw/xen_domainbuild.c b/hw/xen_domainbuild.c
index b73d47f..57fb4f0 100644
--- a/hw/xen_domainbuild.c
+++ b/hw/xen_domainbuild.c
@@ -176,8 +176,9 @@ static int xen_domain_watcher(void)
     for (i = 3; i < n; i++) {
         if (i == fd[0])
             continue;
-        if (i == xen_xc)
+        if (i == xc_fd(xen_xc)) {
             continue;
+        }
         close(i);
     }
 
-- 
1.7.2.3