[RFC Patch 21/25] send store mfn and console mfn to xl before resuming secondary vm

[Wen Congyang <wency@cn.fujitsu.com>]

We will call libxl__xc_domain_restore_done() to rebuild secondary vm. But
we need store mfn and console mfn when rebuilding secondary vm. So make
restore_results is a function pointers in callbacks struct and struct
{save,restore}_callbacks, and use this callback to send store mfn and
console mfn to xl.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
---
 tools/libxc/xc_domain_restore.c    | 2 +-
 tools/libxc/xenguest.h             | 8 ++++++++
 tools/libxl/libxl_colo_restore.c   | 5 -----
 tools/libxl/libxl_create.c         | 1 +
 tools/libxl/libxl_save_msgs_gen.pl | 2 +-
 5 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/tools/libxc/xc_domain_restore.c b/tools/libxc/xc_domain_restore.c
index 6e025f0..dc66d89 100644
--- a/tools/libxc/xc_domain_restore.c
+++ b/tools/libxc/xc_domain_restore.c
@@ -2379,7 +2379,7 @@ new_checkpoint:
     } while (0)
         /* COLO */
 
-        /* TODO: call restore_results */
+        callbacks->restore_results(*store_mfn, *console_mfn, callbacks->data);
 
         /* Resume secondary vm */
         frc = callbacks->postcopy(callbacks->data);
diff --git a/tools/libxc/xenguest.h b/tools/libxc/xenguest.h
index 1aeaad2..be8afd4 100644
--- a/tools/libxc/xenguest.h
+++ b/tools/libxc/xenguest.h
@@ -123,6 +123,14 @@ struct restore_callbacks {
     /* Enable qemu-dm logging dirty pages to xen */
     int (*switch_qemu_logdirty)(int domid, unsigned enable, void *data); /* HVM only */
 
+    /*
+     * callback to send store mfn and console mfn to xl
+     * if we want to resume vm before xc_domain_save()
+     * exits.
+     */
+    void (*restore_results)(unsigned long store_mfn, unsigned long console_mfn,
+                            void *data);
+
     /* callback to restore toolstack specific data */
     int (*toolstack_restore)(uint32_t domid, const uint8_t *buf,
             uint32_t size, void* data);
diff --git a/tools/libxl/libxl_colo_restore.c b/tools/libxl/libxl_colo_restore.c
index ebbd6b9..aea3feb 100644
--- a/tools/libxl/libxl_colo_restore.c
+++ b/tools/libxl/libxl_colo_restore.c
@@ -133,11 +133,6 @@ static void colo_resume_vm(libxl__egc *egc,
         return;
     }
 
-    /*
-     * TODO: get store mfn and console mfn
-     *  We should call the callback restore_results in
-     *  xc_domain_restore() before resuming the guest.
-     */
     libxl__xc_domain_restore_done(egc, dcs, 0, 0, 0);
 
     return;
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index 73708c5..677a98a 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1048,6 +1048,7 @@ static void domcreate_bootloader_done(libxl__egc *egc,
         rc = ERROR_INVAL;
         goto out;
     }
+    callbacks->restore_results = libxl__srm_callout_callback_restore_results;
 
     if (checkpointed_stream == LIBXL_CHECKPOINTED_STREAM_COLO) {
         crs->ao = ao;
diff --git a/tools/libxl/libxl_save_msgs_gen.pl b/tools/libxl/libxl_save_msgs_gen.pl
index fbb2d67..2ecd25d 100755
--- a/tools/libxl/libxl_save_msgs_gen.pl
+++ b/tools/libxl/libxl_save_msgs_gen.pl
@@ -32,7 +32,7 @@ our @msgs = (
     #                toolstack_save          done entirely `by hand'
     [  7, 'rcxW',   "toolstack_restore",     [qw(uint32_t domid
                                                 BLOCK tsdata)] ],
-    [  8, 'r',      "restore_results",       ['unsigned long', 'store_mfn',
+    [  8, 'rcx',    "restore_results",       ['unsigned long', 'store_mfn',
                                               'unsigned long', 'console_mfn'] ],
     [  9, 'srW',    "complete",              [qw(int retval
                                                  int errnoval)] ],
-- 
1.9.3