xen: begin using libxendevicemodel

This library is intended to be a stable interface which device models
can rely on in order to avoid a link time dependency on libxenctrl
(which implies needing to rebuild QEMU when Xen is updated to a new
release, which is a pain for distros)

Rather than go the whole hog all in one go (which would be
unrevieable) this patch adds the basic support and uses it for domain
lifecycle operations. Further patches will add more support.

As with previous patches to use stable libraries the QEMU code now
uses the new stable API on all versions of Xen and stubs out the
necessary code for the older versions.

I had wanted to add the xendevicemodel_handle to the XenIOState
struct, however it does not appear to be possible to get at the state
pointer from all the places where it is needed, specifically the first
such place I tripped over was xen_piix3_set_irq().

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/configure b/configure
index 1e861c185868e8d0aa5d4c8a95de210ecd9d8b32..21c276a3ea715fd38c5c515437997d26a7b6cb0a 100755 (executable)
--- a/configure
+++ b/configure
@@ -253,6 +253,7 @@ xen_ctrl_version=""
 xen_pv_domain_build="no"
 xen_pci_passthrough=""
 xen_restrict_target="no"
+xen_libdevicemodel="no"
 linux_aio=""
 cap_ng=""
 attr=""
@@ -2173,6 +2174,23 @@ EOF
     then
     xen_restrict_target="yes"
   fi
+
+  if
+      cat > $TMPC <<EOF &&
+#include <xendevicemodel.h>
+int main(void) {
+  xendevicemodel_handle *dm;
+
+  dm = xendevicemodel_open(NULL, 0, 0, NULL);
+  xendevicemodel_shutdown(dm);
+  return 0;
+}
+EOF
+      compile_prog "" "-lxendevicemodel"
+    then
+    xen_libdevicemodel="yes"
+    libs_softmmu="$libs_softmmu -lxendevicemodel"
+  fi
 fi
 
 
@@ -4820,6 +4838,7 @@ echo "xen support       $xen"
 if test "$xen" = "yes" ; then
   echo "xen ctrl version  $xen_ctrl_version"
   echo "xen restricted    $xen_restrict_target"
+  echo "xen dm lib        $xen_libdevicemodel"
   echo "pv dom build      $xen_pv_domain_build"
 fi
 echo "brlapi support    $brlapi"
@@ -5198,6 +5217,9 @@ if test "$xen" = "yes" ; then
   if test "$xen_restrict_target" = "yes" ; then
     echo "CONFIG_XEN_RESTRICT_TARGET=y" >> $config_host_mak
   fi
+  if test "$xen_libdevicemodel" = "yes" ; then
+    echo "CONFIG_XEN_LIBDEVICEMODEL=y" >> $config_host_mak
+  fi
 fi
 if test "$linux_aio" = "yes" ; then
   echo "CONFIG_LINUX_AIO=y" >> $config_host_mak

diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 38502c752d08b79580c7eba18ac51824bc468f42..803afd3bf20790ce7f225a88ea1d08d31afd9bc5 100644 (file)
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -99,6 +99,30 @@ static inline int xen_get_vmport_regs_pfn(xc_interface *xc, domid_t dom,
 }
 #endif
 
+#ifdef CONFIG_XEN_LIBDEVICEMODEL
+
+#include <xendevicemodel.h>
+
+#else
+
+typedef xc_interface xendevicemodel_handle;
+
+/* Assumes r (returns restriction status of the handle) is non-NULL in
+ * all actual callers */
+#define xendevicemodel_open(l, d, f, r) ({ *r = ENOSYS; xen_xc; })
+
+#define xendevicemodel_shutdown(h) \
+    xc_domain_shutdown(h, xen_domid, SHUTDOWN_poweroff)
+#define xendevicemodel_reboot(h) \
+    xc_domain_shutdown(h, xen_domid, SHUTDOWN_reboot)
+
+#define xendevicemodel_s3_suspend(h) \
+    xc_set_hvm_param(h, xen_domid, HVM_PARAM_ACPI_S_STATE, 3);
+#define xendevicemodel_s3_awaken(h) \
+    xc_set_hvm_param(h, xen_domid, HVM_PARAM_ACPI_S_STATE, 0);
+
+#endif
+
 /* Xen before 4.6 */
 #if CONFIG_XEN_CTRL_INTERFACE_VERSION < 460
 

diff --git a/xen-hvm.c b/xen-hvm.c
index 921269cc3439741da18e3ec24ee33428778ce272..28514ccf552f4232360911ecc7304708bc2957ac 100644 (file)
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -42,6 +42,7 @@
 static MemoryRegion ram_memory, ram_640k, ram_lo, ram_hi;
 static MemoryRegion *framebuffer;
 static bool xen_in_migration;
+static xendevicemodel_handle *xen_dm = NULL;
 
 /* Compatibility with older version */
 
@@ -159,9 +160,9 @@ void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
     xc_hvm_inject_msi(xen_xc, xen_domid, addr, data);
 }
 
-static void xen_suspend_notifier(Notifier *notifier, void *data)
+static void xen_suspend_notifier(Notifier *n, void *data)
 {
-    xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 3);
+    xendevicemodel_s3_suspend(xen_dm);
 }
 
 /* Xen Interrupt Controller */
@@ -1029,11 +1030,12 @@ static void destroy_hvm_domain(bool reboot)
 {
     int sts;
 
-    sts = xc_domain_shutdown(xen_xc, xen_domid,
-                             reboot ? SHUTDOWN_reboot : SHUTDOWN_poweroff);
+    sts = (reboot ?
+           xendevicemodel_reboot(xen_dm) :
+           xendevicemodel_shutdown(xen_dm));
     if (sts != 0) {
-        fprintf(stderr, "xc_domain_shutdown failed to issue %s, "
-                "sts %d, %s\n", reboot ? "reboot" : "poweroff",
+        fprintf(stderr, "failed to issue %s, sts %d, %s\n",
+                reboot ? "reboot" : "poweroff",
                 sts, strerror(errno));
     } else {
         fprintf(stderr, "Issued domain %d %s\n", xen_domid,
@@ -1179,9 +1181,9 @@ static void xen_read_physmap(XenIOState *state)
     free(entries);
 }
 
-static void xen_wakeup_notifier(Notifier *notifier, void *data)
+static void xen_wakeup_notifier(Notifier *n, void *data)
 {
-    xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 0);
+    xendevicemodel_s3_awaken(xen_dm);
 }
 
 static bool xen_restrict_targets = true; /* XXX configurable? */
@@ -1202,6 +1204,7 @@ static bool xen_restrict_target_failure_is_fatal(const char *which, int errnoval
 
     error_report("restricting %s handle failed: %d: %s",
                  which, errnoval, strerror(errnoval));
+
     return true;
 }
 
@@ -1212,6 +1215,7 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
     xen_pfn_t bufioreq_pfn;
     evtchn_port_t bufioreq_evtchn;
     XenIOState *state;
+    int dm_restrict_errno;
 
     state = g_malloc0(sizeof (XenIOState));
 
@@ -1243,6 +1247,15 @@ void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
     if (rc < 0 && xen_restrict_target_failure_is_fatal("xenforeignmemory", errno))
         goto err;
 
+    xen_dm = xendevicemodel_open(NULL, xen_domid, 0, &dm_restrict_errno);
+    if (!xen_dm) {
+        perror("xen: dm handle create");
+        goto err;
+    }
+    if (dm_restrict_errno &&
+        xen_restrict_target_failure_is_fatal("xendevicemodel", dm_restrict_errno))
+        goto err;
+
     rc = xen_create_ioreq_server(xen_xc, xen_domid, &state->ioservid);
     if (rc < 0) {
         perror("xen: ioreq server create");