[PATCH 25/29] tools/xenstored: mount 9pfs device in stubdom

[Juergen Gross <jgross@xxxxxxxx>]

Mount the 9pfs device in stubdom enabling it to use files.

This has to happen in a worker thread in order to allow the main thread
handling the required Xenstore accesses in parallel.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 tools/xenstored/core.h   |  5 +++++
 tools/xenstored/domain.c |  2 ++
 tools/xenstored/minios.c | 35 +++++++++++++++++++++++++++++++++++
 3 files changed, 42 insertions(+)

diff --git a/tools/xenstored/core.h b/tools/xenstored/core.h
index f7a27a4131..48ff659ec5 100644
--- a/tools/xenstored/core.h
+++ b/tools/xenstored/core.h
@@ -35,6 +35,8 @@
 #include "list.h"
 #include "hashtable.h"
 
+#define XENSTORE_LIB_DIR       XEN_LIB_DIR "/xenstore"
+
 #ifndef O_CLOEXEC
 #define O_CLOEXEC 0
 /* O_CLOEXEC support is needed for Live Update in the daemon case. */
@@ -385,6 +387,9 @@ static inline bool domain_is_unprivileged(const struct 
connection *conn)
 
 /* Return the event channel used by xenbus. */
 evtchn_port_t get_xenbus_evtchn(void);
+#ifdef __MINIOS__
+void mount_9pfs(void);
+#endif
 
 /* Write out the pidfile */
 void write_pidfile(const char *pidfile);
diff --git a/tools/xenstored/domain.c b/tools/xenstored/domain.c
index 162b87b460..4263c1360f 100644
--- a/tools/xenstored/domain.c
+++ b/tools/xenstored/domain.c
@@ -1236,6 +1236,8 @@ void stubdom_init(void)
                barf_perror("Failed to initialize stubdom");
 
        xenevtchn_notify(xce_handle, stubdom->port);
+
+       mount_9pfs();
 #endif
 }
 
diff --git a/tools/xenstored/minios.c b/tools/xenstored/minios.c
index 0779efbf91..e5a3684df6 100644
--- a/tools/xenstored/minios.c
+++ b/tools/xenstored/minios.c
@@ -19,6 +19,14 @@
 #include <sys/mman.h>
 #include "core.h"
 #include <xen/grant_table.h>
+#include <mini-os/9pfront.h>
+#include <mini-os/sched.h>
+#include <mini-os/xenbus.h>
+#include <mini-os/xmalloc.h>
+
+#define P9_STATE_PATH  "device/9pfs/0/state"
+
+static void *p9_device;
 
 void write_pidfile(const char *pidfile)
 {
@@ -54,3 +62,30 @@ void unmap_xenbus(void *interface)
        xengnttab_unmap(*xgt_handle, interface, 1);
 }
 
+static void mount_thread(void *p)
+{
+       xenbus_event_queue events = NULL;
+       char *err;
+       char *dummy;
+
+       free(xenbus_watch_path_token(XBT_NIL, P9_STATE_PATH, "9pfs", &events));
+
+       for (;;) {
+               xenbus_wait_for_watch(&events);
+               err = xenbus_read(XBT_NIL, P9_STATE_PATH, &dummy);
+               if (!err)
+                       break;
+               free(err);
+       }
+
+       free(dummy);
+
+       free(xenbus_unwatch_path_token(XBT_NIL, P9_STATE_PATH, "9pfs"));
+
+       p9_device = init_9pfront(0, XENSTORE_LIB_DIR);
+}
+
+void mount_9pfs(void)
+{
+       create_thread("mount-9pfs", mount_thread, NULL);
+}
-- 
2.35.3