[v5,4/5] libxl: add service function to check whether device model is running

Commit Message

Jürgen Groß March 30, 2016, 12:05 p.m. UTC

Add an internal service function to check for a running device model.
This can be used later when adding devices to a domain requiring a
device model for either printing an error message or starting the
device model in case it is not already running.

Signed-off-by: Juergen Gross <[e-mail]>
Acked-by: Wei Liu <[e-mail]>
---
 tools/libxl/libxl.c          |  4 +---
 tools/libxl/libxl_dm.c       | 10 ++++++++++
 tools/libxl/libxl_internal.h |  1 +
 3 files changed, 12 insertions(+), 3 deletions(-)

Patch

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 5c473e7..bb6a689 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -1532,7 +1532,6 @@  void libxl__destroy_domid(libxl__egc *egc, libxl__destroy_domid_state *dis)
     libxl_ctx *ctx = CTX;
     uint32_t domid = dis->domid;
     char *dom_path;
-    char *pid;
     int rc, dm_present;
 
     libxl__ev_child_init(&dis->destroyer);
@@ -1555,8 +1554,7 @@  void libxl__destroy_domid(libxl__egc *egc, libxl__destroy_domid_state *dis)
         }
         /* fall through */
     case LIBXL_DOMAIN_TYPE_PV:
-        pid = libxl__xs_read(gc, XBT_NULL, GCSPRINTF("/local/domain/%d/image/device-model-pid", domid));
-        dm_present = (pid != NULL);
+        dm_present = libxl__dm_active(gc, domid);
         break;
     case LIBXL_DOMAIN_TYPE_INVALID:
         rc = ERROR_FAIL;
diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c
index 8f5c4e6..e60e125 100644
--- a/tools/libxl/libxl_dm.c
+++ b/tools/libxl/libxl_dm.c
@@ -2178,6 +2178,16 @@  out:
     return ret;
 }
 
+int libxl__dm_active(libxl__gc *gc, uint32_t domid)
+{
+    char *pid, *path;
+
+    path = GCSPRINTF("/local/domain/%d/image/device-model-pid", domid);
+    pid = libxl__xs_read(gc, XBT_NULL, path);
+
+    return pid != NULL;
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 20b6122..144c715 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -1623,6 +1623,7 @@  _hidden bool libxl__query_qemu_backend(libxl__gc *gc,
                                        uint32_t backend_id,
                                        const char *type,
                                        bool def);
+_hidden int libxl__dm_active(libxl__gc *gc, uint32_t domid);
 
 /*
  * This function will fix reserved device memory conflict