[v6,04/18] libxl/save: Refactor libxl__domain_suspend_state

Commit Message

Wen Congyang Dec. 30, 2015, 2:28 a.m. UTC

Currently struct libxl__domain_suspend_state contains 2 type of states,
one is save state, another is suspend state. This patch separates those
two out.
The motivation of this is that COLO will need to do suspend/resume
continuously, we need a more common suspend state.

After this change, dss stands for libxl__domain_save_state,
dsps stands for libxl__domain_suspend_state.

Also introduce libxl__domain_suspend_init to initialise the
libxl__domain_suspend_state.

Signed-off-by: Yang Hongyang <[e-mail]>
Signed-off-by: Wen Congyang <[e-mail]>
CC: Ian Campbell <[e-mail]>
CC: Ian Jackson <[e-mail]>
CC: Wei Liu <[e-mail]>
CC: Andrew Cooper <[e-mail]>
Acked-by:Ian Campbell <[e-mail]>
---
 tools/libxl/libxl.c              |  10 +-
 tools/libxl/libxl_create.c       |  10 +-
 tools/libxl/libxl_dom_save.c     |  61 ++++-------
 tools/libxl/libxl_dom_suspend.c  | 217 +++++++++++++++++++++++++--------------
 tools/libxl/libxl_internal.h     |  60 +++++++----
 tools/libxl/libxl_netbuffer.c    |   2 +-
 tools/libxl/libxl_remus.c        |  37 ++++---
 tools/libxl/libxl_save_callout.c |   2 +-
 tools/libxl/libxl_stream_write.c |  16 +--
 9 files changed, 236 insertions(+), 179 deletions(-)

Comments

Konrad Rzeszutek Wilk Jan. 25, 2016, 5:29 p.m. UTC | #1

.snip..
> --- a/tools/libxl/libxl_dom_suspend.c
> +++ b/tools/libxl/libxl_dom_suspend.c
> @@ -19,14 +19,71 @@
>  
>  /*====================== Domain suspend =======================*/
>  
> +int libxl__domain_suspend_init(libxl__egc *egc,
> +                               libxl__domain_suspend_state *dsps)
> +{
> +    STATE_AO_GC(dsps->ao);
> +    int rc = ERROR_FAIL;
> +    int port;
> +    libxl_domain_type type;
> +
> +    /* Convenience aliases */
> +    const uint32_t domid = dsps->domid;
> +
> +    type = libxl__domain_type(gc, domid);
> +    switch (type) {
> +    case LIBXL_DOMAIN_TYPE_HVM: {
> +        dsps->hvm = 1;
> +        break;
> +    }
> +    case LIBXL_DOMAIN_TYPE_PV:
> +        dsps->hvm = 0;
> +        break;
> +    default:
> +        goto out;

This will mean we return back to libxl__domain_save which will goto out which calls:
domain_save_done. And that will try to use the dsps->guestevtchn leading to a crash since:
> +    }
> +
> +    libxl__xswait_init(&dsps->pvcontrol);
> +    libxl__ev_evtchn_init(&dsps->guest_evtchn);

we initialize them here.
> +    libxl__ev_xswatch_init(&dsps->guest_watch);
> +    libxl__ev_time_init(&dsps->guest_timeout);

I would instead recommend you move these initialization routines above the
'type' check.

> +
> +    dsps->guest_evtchn.port = -1;
> +    dsps->guest_evtchn_lockfd = -1;
> +    dsps->guest_responded = 0;
> +    dsps->dm_savefile = libxl__device_model_savefile(gc, domid);
> +
> +    port = xs_suspend_evtchn_port(domid);
> +
> +    if (port >= 0) {
> +        rc = libxl__ctx_evtchn_init(gc);
> +        if (rc) goto out;
> +
> +        dsps->guest_evtchn.port =
> +            xc_suspend_evtchn_init_exclusive(CTX->xch, CTX->xce,
> +                                    domid, port, &dsps->guest_evtchn_lockfd);
> +
> +        if (dsps->guest_evtchn.port < 0) {
> +            LOG(WARN, "Suspend event channel initialization failed");
> +            rc = ERROR_FAIL;
> +            goto out;
> +        }
> +    }
> +
> +    rc = 0;
> +
> +out:
> +    return rc;
> +}
> +

.. snip..
>  struct libxl__domain_suspend_state {
> +    /* set by caller of libxl__domain_suspend_init */
> +    libxl__ao *ao;
> +    uint32_t domid;
> +
> +    /* private */
> +    int hvm;

How about 'is_hvm' and just use 'libxl_domain_type' type?
instead of having an int? You can just do:

if (type == LIBXL_DOMAIN_TYPE_HVM) ..

And to check for non-conforming types - you can make  libxl__domain_suspend_init
do this:

    if (type == LIBXL_DOMAIN_TYPE_INVALID) {
        rc = ERROR_FAIL;
        goto out; 
    }    

?

Wen Congyang Jan. 26, 2016, 2:23 a.m. UTC | #2

On 01/26/2016 01:29 AM, Konrad Rzeszutek Wilk wrote:
> .snip..
>> --- a/tools/libxl/libxl_dom_suspend.c
>> +++ b/tools/libxl/libxl_dom_suspend.c
>> @@ -19,14 +19,71 @@
>>  
>>  /*====================== Domain suspend =======================*/
>>  
>> +int libxl__domain_suspend_init(libxl__egc *egc,
>> +                               libxl__domain_suspend_state *dsps)
>> +{
>> +    STATE_AO_GC(dsps->ao);
>> +    int rc = ERROR_FAIL;
>> +    int port;
>> +    libxl_domain_type type;
>> +
>> +    /* Convenience aliases */
>> +    const uint32_t domid = dsps->domid;
>> +
>> +    type = libxl__domain_type(gc, domid);
>> +    switch (type) {
>> +    case LIBXL_DOMAIN_TYPE_HVM: {
>> +        dsps->hvm = 1;
>> +        break;
>> +    }
>> +    case LIBXL_DOMAIN_TYPE_PV:
>> +        dsps->hvm = 0;
>> +        break;
>> +    default:
>> +        goto out;
> 
> This will mean we return back to libxl__domain_save which will goto out which calls:
> domain_save_done. And that will try to use the dsps->guestevtchn leading to a crash since:

Yes, thanks for pointing it out. In which case, the type is not HVM or PV?

>> +    }
>> +
>> +    libxl__xswait_init(&dsps->pvcontrol);
>> +    libxl__ev_evtchn_init(&dsps->guest_evtchn);
> 
> we initialize them here.
>> +    libxl__ev_xswatch_init(&dsps->guest_watch);
>> +    libxl__ev_time_init(&dsps->guest_timeout);
> 
> I would instead recommend you move these initialization routines above the
> 'type' check.

I think we should not return ERROR_FAIL when the type is not PV or HVM. We should abort the program
like what we do in libxl__domain_save().

> 
>> +
>> +    dsps->guest_evtchn.port = -1;
>> +    dsps->guest_evtchn_lockfd = -1;
>> +    dsps->guest_responded = 0;
>> +    dsps->dm_savefile = libxl__device_model_savefile(gc, domid);
>> +
>> +    port = xs_suspend_evtchn_port(domid);
>> +
>> +    if (port >= 0) {
>> +        rc = libxl__ctx_evtchn_init(gc);
>> +        if (rc) goto out;
>> +
>> +        dsps->guest_evtchn.port =
>> +            xc_suspend_evtchn_init_exclusive(CTX->xch, CTX->xce,
>> +                                    domid, port, &dsps->guest_evtchn_lockfd);
>> +
>> +        if (dsps->guest_evtchn.port < 0) {
>> +            LOG(WARN, "Suspend event channel initialization failed");
>> +            rc = ERROR_FAIL;
>> +            goto out;
>> +        }
>> +    }
>> +
>> +    rc = 0;
>> +
>> +out:
>> +    return rc;
>> +}
>> +
> 
> .. snip..
>>  struct libxl__domain_suspend_state {
>> +    /* set by caller of libxl__domain_suspend_init */
>> +    libxl__ao *ao;
>> +    uint32_t domid;
>> +
>> +    /* private */
>> +    int hvm;
> 
> How about 'is_hvm' and just use 'libxl_domain_type' type?
> instead of having an int? You can just do:

In dss, it is 'int hvm'.
Before this patch:
if (dss->hvm) ...
After this patch:
if (dsps->hvm) ...

Thanks
Wen Congyang

> 
> if (type == LIBXL_DOMAIN_TYPE_HVM) ..
> 
> And to check for non-conforming types - you can make  libxl__domain_suspend_init
> do this:
> 
>     if (type == LIBXL_DOMAIN_TYPE_INVALID) {
>         rc = ERROR_FAIL;
>         goto out; 
>     }    
> 
> ?
> 
> 
> .
>

Konrad Rzeszutek Wilk Jan. 26, 2016, 2:32 p.m. UTC | #3

On Tue, Jan 26, 2016 at 10:23:52AM +0800, Wen Congyang wrote:
> On 01/26/2016 01:29 AM, Konrad Rzeszutek Wilk wrote:
> > .snip..
> >> --- a/tools/libxl/libxl_dom_suspend.c
> >> +++ b/tools/libxl/libxl_dom_suspend.c
> >> @@ -19,14 +19,71 @@
> >>  
> >>  /*====================== Domain suspend =======================*/
> >>  
> >> +int libxl__domain_suspend_init(libxl__egc *egc,
> >> +                               libxl__domain_suspend_state *dsps)
> >> +{
> >> +    STATE_AO_GC(dsps->ao);
> >> +    int rc = ERROR_FAIL;
> >> +    int port;
> >> +    libxl_domain_type type;
> >> +
> >> +    /* Convenience aliases */
> >> +    const uint32_t domid = dsps->domid;
> >> +
> >> +    type = libxl__domain_type(gc, domid);
> >> +    switch (type) {
> >> +    case LIBXL_DOMAIN_TYPE_HVM: {
> >> +        dsps->hvm = 1;
> >> +        break;
> >> +    }
> >> +    case LIBXL_DOMAIN_TYPE_PV:
> >> +        dsps->hvm = 0;
> >> +        break;
> >> +    default:
> >> +        goto out;
> > 
> > This will mean we return back to libxl__domain_save which will goto out which calls:
> > domain_save_done. And that will try to use the dsps->guestevtchn leading to a crash since:
> 
> Yes, thanks for pointing it out. In which case, the type is not HVM or PV?

If you call those init routines before the switch statemet - such as the
libxl__xswait_init, etc, then you can still goto out
> 
> >> +    }
> >> +
> >> +    libxl__xswait_init(&dsps->pvcontrol);
> >> +    libxl__ev_evtchn_init(&dsps->guest_evtchn);
> > 
> > we initialize them here.
> >> +    libxl__ev_xswatch_init(&dsps->guest_watch);
> >> +    libxl__ev_time_init(&dsps->guest_timeout);
> > 
> > I would instead recommend you move these initialization routines above the
> > 'type' check.
> 
> I think we should not return ERROR_FAIL when the type is not PV or HVM. We should abort the program
> like what we do in libxl__domain_save().

I would rather return - this is a library after all - so the controlling program should
do such drastic measures - not an library.

> 
> > 
> >> +
> >> +    dsps->guest_evtchn.port = -1;
> >> +    dsps->guest_evtchn_lockfd = -1;
> >> +    dsps->guest_responded = 0;
> >> +    dsps->dm_savefile = libxl__device_model_savefile(gc, domid);
> >> +
> >> +    port = xs_suspend_evtchn_port(domid);
> >> +
> >> +    if (port >= 0) {
> >> +        rc = libxl__ctx_evtchn_init(gc);
> >> +        if (rc) goto out;
> >> +
> >> +        dsps->guest_evtchn.port =
> >> +            xc_suspend_evtchn_init_exclusive(CTX->xch, CTX->xce,
> >> +                                    domid, port, &dsps->guest_evtchn_lockfd);
> >> +
> >> +        if (dsps->guest_evtchn.port < 0) {
> >> +            LOG(WARN, "Suspend event channel initialization failed");
> >> +            rc = ERROR_FAIL;
> >> +            goto out;
> >> +        }
> >> +    }
> >> +
> >> +    rc = 0;
> >> +
> >> +out:
> >> +    return rc;
> >> +}
> >> +
> > 
> > .. snip..
> >>  struct libxl__domain_suspend_state {
> >> +    /* set by caller of libxl__domain_suspend_init */
> >> +    libxl__ao *ao;
> >> +    uint32_t domid;
> >> +
> >> +    /* private */
> >> +    int hvm;
> > 
> > How about 'is_hvm' and just use 'libxl_domain_type' type?
> > instead of having an int? You can just do:
> 
> In dss, it is 'int hvm'.
> Before this patch:
> if (dss->hvm) ...
> After this patch:
> if (dsps->hvm) ...

Right..
> 
> Thanks
> Wen Congyang
> 
> > 
> > if (type == LIBXL_DOMAIN_TYPE_HVM) ..

But what if you use that? As in dsps->type == LIBXL_DOMAIAN_TYPE_HVM for example?

> > 
> > And to check for non-conforming types - you can make  libxl__domain_suspend_init
> > do this:
> > 
> >     if (type == LIBXL_DOMAIN_TYPE_INVALID) {
> >         rc = ERROR_FAIL;
> >         goto out; 
> >     }    
> > 
> > ?
> > 
> > 
> > .
> > 
> 
> 
>

Patch

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index bdd8ad0..f8f7158 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -833,7 +833,7 @@  out:
 }
 
 static void remus_failover_cb(libxl__egc *egc,
-                              libxl__domain_suspend_state *dss, int rc);
+                              libxl__domain_save_state *dss, int rc);
 
 /* TODO: Explicit Checkpoint acknowledgements via recv_fd. */
 int libxl_domain_remus_start(libxl_ctx *ctx, libxl_domain_remus_info *info,
@@ -841,7 +841,7 @@  int libxl_domain_remus_start(libxl_ctx *ctx, libxl_domain_remus_info *info,
                              const libxl_asyncop_how *ao_how)
 {
     AO_CREATE(ctx, domid, ao_how);
-    libxl__domain_suspend_state *dss;
+    libxl__domain_save_state *dss;
     int rc;
 
     libxl_domain_type type = libxl__domain_type(gc, domid);
@@ -889,7 +889,7 @@  int libxl_domain_remus_start(libxl_ctx *ctx, libxl_domain_remus_info *info,
 }
 
 static void remus_failover_cb(libxl__egc *egc,
-                              libxl__domain_suspend_state *dss, int rc)
+                              libxl__domain_save_state *dss, int rc)
 {
     STATE_AO_GC(dss->ao);
     /*
@@ -901,7 +901,7 @@  static void remus_failover_cb(libxl__egc *egc,
 }
 
 static void domain_suspend_cb(libxl__egc *egc,
-                              libxl__domain_suspend_state *dss, int rc)
+                              libxl__domain_save_state *dss, int rc)
 {
     STATE_AO_GC(dss->ao);
     int flrc;
@@ -926,7 +926,7 @@  int libxl_domain_suspend(libxl_ctx *ctx, uint32_t domid, int fd, int flags,
         goto out_err;
     }
 
-    libxl__domain_suspend_state *dss;
+    libxl__domain_save_state *dss;
     GCNEW(dss);
 
     dss->ao = ao;
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index 0ee9a57..bfa0552 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1540,7 +1540,7 @@  typedef struct {
 typedef struct {
     libxl__app_domain_create_state cdcs;
     libxl__domain_destroy_state dds;
-    libxl__domain_suspend_state dss;
+    libxl__domain_save_state dss;
     char *toolstack_buf;
     uint32_t toolstack_len;
 } libxl__domain_soft_reset_state;
@@ -1635,7 +1635,7 @@  static int do_domain_soft_reset(libxl_ctx *ctx,
     libxl__app_domain_create_state *cdcs;
     libxl__domain_create_state *dcs;
     libxl__domain_build_state *state;
-    libxl__domain_suspend_state *dss;
+    libxl__domain_save_state *dss;
     char *dom_path, *xs_store_mfn, *xs_console_mfn;
     uint32_t domid_out;
     int rc;
@@ -1679,8 +1679,8 @@  static int do_domain_soft_reset(libxl_ctx *ctx,
 
     dss->ao = ao;
     dss->domid = domid_soft_reset;
-    dss->dm_savefile = GCSPRINTF(LIBXL_DEVICE_MODEL_SAVE_FILE".%d",
-                                 domid_soft_reset);
+    dss->dsps.dm_savefile = GCSPRINTF(LIBXL_DEVICE_MODEL_SAVE_FILE".%d",
+                                      domid_soft_reset);
 
     rc = libxl__save_emulator_xenstore_data(dss, &srs->toolstack_buf,
                                             &srs->toolstack_len);
@@ -1689,7 +1689,7 @@  static int do_domain_soft_reset(libxl_ctx *ctx,
         goto out;
     }
 
-    rc = libxl__domain_suspend_device_model(gc, dss);
+    rc = libxl__domain_suspend_device_model(gc, &dss->dsps);
     if (rc) {
         LOG(ERROR, "failed to suspend device model.");
         goto out;
diff --git a/tools/libxl/libxl_dom_save.c b/tools/libxl/libxl_dom_save.c
index 27fd58b..cc8cabe 100644
--- a/tools/libxl/libxl_dom_save.c
+++ b/tools/libxl/libxl_dom_save.c
@@ -24,7 +24,7 @@ 
 static void stream_done(libxl__egc *egc,
                         libxl__stream_write_state *sws, int rc);
 static void domain_save_done(libxl__egc *egc,
-                             libxl__domain_suspend_state *dss, int rc);
+                             libxl__domain_save_state *dss, int rc);
 
 /*----- complicated callback, called by xc_domain_save -----*/
 
@@ -42,7 +42,7 @@  static void switch_logdirty_timeout(libxl__egc *egc, libxl__ev_time *ev,
 static void switch_logdirty_xswatch(libxl__egc *egc, libxl__ev_xswatch*,
                             const char *watch_path, const char *event_path);
 static void switch_logdirty_done(libxl__egc *egc,
-                                 libxl__domain_suspend_state *dss, int rc);
+                                 libxl__domain_save_state *dss, int rc);
 
 static void logdirty_init(libxl__logdirty_switch *lds)
 {
@@ -56,7 +56,7 @@  static void domain_suspend_switch_qemu_xen_traditional_logdirty
                                 libxl__save_helper_state *shs)
 {
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
     libxl__logdirty_switch *lds = &dss->logdirty;
     STATE_AO_GC(dss->ao);
     int rc;
@@ -128,7 +128,7 @@  static void domain_suspend_switch_qemu_xen_logdirty
                                 libxl__save_helper_state *shs)
 {
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
     STATE_AO_GC(dss->ao);
     int rc;
 
@@ -147,7 +147,7 @@  void libxl__domain_suspend_common_switch_qemu_logdirty
 {
     libxl__save_helper_state *shs = user;
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
     STATE_AO_GC(dss->ao);
 
     switch (libxl__device_model_version_running(gc, domid)) {
@@ -171,7 +171,7 @@  static void switch_logdirty_timeout(libxl__egc *egc, libxl__ev_time *ev,
                                     const struct timeval *requested_abs,
                                     int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(ev, *dss, logdirty.timeout);
+    libxl__domain_save_state *dss = CONTAINER_OF(ev, *dss, logdirty.timeout);
     STATE_AO_GC(dss->ao);
     LOG(ERROR,"logdirty switch: wait for device model timed out");
     switch_logdirty_done(egc,dss,ERROR_FAIL);
@@ -180,7 +180,7 @@  static void switch_logdirty_timeout(libxl__egc *egc, libxl__ev_time *ev,
 static void switch_logdirty_xswatch(libxl__egc *egc, libxl__ev_xswatch *watch,
                             const char *watch_path, const char *event_path)
 {
-    libxl__domain_suspend_state *dss =
+    libxl__domain_save_state *dss =
         CONTAINER_OF(watch, *dss, logdirty.watch);
     libxl__logdirty_switch *lds = &dss->logdirty;
     STATE_AO_GC(dss->ao);
@@ -234,7 +234,7 @@  static void switch_logdirty_xswatch(libxl__egc *egc, libxl__ev_xswatch *watch,
 }
 
 static void switch_logdirty_done(libxl__egc *egc,
-                                 libxl__domain_suspend_state *dss,
+                                 libxl__domain_save_state *dss,
                                  int rc)
 {
     STATE_AO_GC(dss->ao);
@@ -270,7 +270,7 @@  static void append_string(libxl__gc *gc, char **buf, uint32_t *len,
     *len += extralen;
 }
 
-int libxl__save_emulator_xenstore_data(libxl__domain_suspend_state *dss,
+int libxl__save_emulator_xenstore_data(libxl__domain_save_state *dss,
                                        char **callee_buf,
                                        uint32_t *callee_len)
 {
@@ -322,10 +322,9 @@  int libxl__save_emulator_xenstore_data(libxl__domain_suspend_state *dss,
 
 /*----- main code for saving, in order of execution -----*/
 
-void libxl__domain_save(libxl__egc *egc, libxl__domain_suspend_state *dss)
+void libxl__domain_save(libxl__egc *egc, libxl__domain_save_state *dss)
 {
     STATE_AO_GC(dss->ao);
-    int port;
     int rc, ret;
 
     /* Convenience aliases */
@@ -337,13 +336,14 @@  void libxl__domain_save(libxl__egc *egc, libxl__domain_suspend_state *dss)
     libxl__srm_save_autogen_callbacks *const callbacks =
         &dss->sws.shs.callbacks.save.a;
     unsigned int nr_vnodes = 0, nr_vmemranges = 0, nr_vcpus = 0;
+    libxl__domain_suspend_state *dsps = &dss->dsps;
 
     dss->rc = 0;
     logdirty_init(&dss->logdirty);
-    libxl__xswait_init(&dss->pvcontrol);
-    libxl__ev_evtchn_init(&dss->guest_evtchn);
-    libxl__ev_xswatch_init(&dss->guest_watch);
-    libxl__ev_time_init(&dss->guest_timeout);
+    dsps->ao = ao;
+    dsps->domid = domid;
+    rc = libxl__domain_suspend_init(egc, dsps);
+    if (rc) goto out;
 
     switch (type) {
     case LIBXL_DOMAIN_TYPE_HVM: {
@@ -376,11 +376,6 @@  void libxl__domain_save(libxl__egc *egc, libxl__domain_suspend_state *dss)
         goto out;
     }
 
-    dss->guest_evtchn.port = -1;
-    dss->guest_evtchn_lockfd = -1;
-    dss->guest_responded = 0;
-    dss->dm_savefile = libxl__device_model_savefile(gc, domid);
-
     if (r_info != NULL) {
         dss->interval = r_info->interval;
         dss->xcflags |= XCFLAGS_CHECKPOINTED;
@@ -388,23 +383,6 @@  void libxl__domain_save(libxl__egc *egc, libxl__domain_suspend_state *dss)
             dss->xcflags |= XCFLAGS_CHECKPOINT_COMPRESS;
     }
 
-    port = xs_suspend_evtchn_port(dss->domid);
-
-    if (port >= 0) {
-        rc = libxl__ctx_evtchn_init(gc);
-        if (rc) goto out;
-
-        dss->guest_evtchn.port =
-            xc_suspend_evtchn_init_exclusive(CTX->xch, CTX->xce,
-                                  dss->domid, port, &dss->guest_evtchn_lockfd);
-
-        if (dss->guest_evtchn.port < 0) {
-            LOG(WARN, "Suspend event channel initialization failed");
-            rc = ERROR_FAIL;
-            goto out;
-        }
-    }
-
     memset(callbacks, 0, sizeof(*callbacks));
     if (r_info != NULL) {
         callbacks->suspend = libxl__remus_domain_suspend_callback;
@@ -434,18 +412,19 @@  static void stream_done(libxl__egc *egc,
 }
 
 static void domain_save_done(libxl__egc *egc,
-                             libxl__domain_suspend_state *dss, int rc)
+                             libxl__domain_save_state *dss, int rc)
 {
     STATE_AO_GC(dss->ao);
 
     /* Convenience aliases */
     const uint32_t domid = dss->domid;
+    libxl__domain_suspend_state *dsps = &dss->dsps;
 
-    libxl__ev_evtchn_cancel(gc, &dss->guest_evtchn);
+    libxl__ev_evtchn_cancel(gc, &dsps->guest_evtchn);
 
-    if (dss->guest_evtchn.port > 0)
+    if (dsps->guest_evtchn.port > 0)
         xc_suspend_evtchn_release(CTX->xch, CTX->xce, domid,
-                           dss->guest_evtchn.port, &dss->guest_evtchn_lockfd);
+                        dsps->guest_evtchn.port, &dsps->guest_evtchn_lockfd);
 
     if (dss->remus) {
         /*
diff --git a/tools/libxl/libxl_dom_suspend.c b/tools/libxl/libxl_dom_suspend.c
index 3313ad1..f8185fb 100644
--- a/tools/libxl/libxl_dom_suspend.c
+++ b/tools/libxl/libxl_dom_suspend.c
@@ -19,14 +19,71 @@ 
 
 /*====================== Domain suspend =======================*/
 
+int libxl__domain_suspend_init(libxl__egc *egc,
+                               libxl__domain_suspend_state *dsps)
+{
+    STATE_AO_GC(dsps->ao);
+    int rc = ERROR_FAIL;
+    int port;
+    libxl_domain_type type;
+
+    /* Convenience aliases */
+    const uint32_t domid = dsps->domid;
+
+    type = libxl__domain_type(gc, domid);
+    switch (type) {
+    case LIBXL_DOMAIN_TYPE_HVM: {
+        dsps->hvm = 1;
+        break;
+    }
+    case LIBXL_DOMAIN_TYPE_PV:
+        dsps->hvm = 0;
+        break;
+    default:
+        goto out;
+    }
+
+    libxl__xswait_init(&dsps->pvcontrol);
+    libxl__ev_evtchn_init(&dsps->guest_evtchn);
+    libxl__ev_xswatch_init(&dsps->guest_watch);
+    libxl__ev_time_init(&dsps->guest_timeout);
+
+    dsps->guest_evtchn.port = -1;
+    dsps->guest_evtchn_lockfd = -1;
+    dsps->guest_responded = 0;
+    dsps->dm_savefile = libxl__device_model_savefile(gc, domid);
+
+    port = xs_suspend_evtchn_port(domid);
+
+    if (port >= 0) {
+        rc = libxl__ctx_evtchn_init(gc);
+        if (rc) goto out;
+
+        dsps->guest_evtchn.port =
+            xc_suspend_evtchn_init_exclusive(CTX->xch, CTX->xce,
+                                    domid, port, &dsps->guest_evtchn_lockfd);
+
+        if (dsps->guest_evtchn.port < 0) {
+            LOG(WARN, "Suspend event channel initialization failed");
+            rc = ERROR_FAIL;
+            goto out;
+        }
+    }
+
+    rc = 0;
+
+out:
+    return rc;
+}
+
 /*----- callbacks, called by xc_domain_save -----*/
 
 int libxl__domain_suspend_device_model(libxl__gc *gc,
-                                       libxl__domain_suspend_state *dss)
+                                       libxl__domain_suspend_state *dsps)
 {
     int ret = 0;
-    uint32_t const domid = dss->domid;
-    const char *const filename = dss->dm_savefile;
+    uint32_t const domid = dsps->domid;
+    const char *const filename = dsps->dm_savefile;
 
     switch (libxl__device_model_version_running(gc, domid)) {
     case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: {
@@ -53,9 +110,9 @@  int libxl__domain_suspend_device_model(libxl__gc *gc,
 }
 
 static void domain_suspend_common_wait_guest(libxl__egc *egc,
-                                             libxl__domain_suspend_state *dss);
+                                             libxl__domain_suspend_state *dsps);
 static void domain_suspend_common_guest_suspended(libxl__egc *egc,
-                                         libxl__domain_suspend_state *dss);
+                                         libxl__domain_suspend_state *dsps);
 
 static void domain_suspend_common_pvcontrol_suspending(libxl__egc *egc,
       libxl__xswait_state *xswa, int rc, const char *state);
@@ -64,24 +121,24 @@  static void domain_suspend_common_wait_guest_evtchn(libxl__egc *egc,
 static void suspend_common_wait_guest_watch(libxl__egc *egc,
       libxl__ev_xswatch *xsw, const char *watch_path, const char *event_path);
 static void suspend_common_wait_guest_check(libxl__egc *egc,
-        libxl__domain_suspend_state *dss);
+        libxl__domain_suspend_state *dsps);
 static void suspend_common_wait_guest_timeout(libxl__egc *egc,
       libxl__ev_time *ev, const struct timeval *requested_abs, int rc);
 
 static void domain_suspend_common_done(libxl__egc *egc,
-                                       libxl__domain_suspend_state *dss,
+                                       libxl__domain_suspend_state *dsps,
                                        int rc);
 
 static void domain_suspend_callback_common(libxl__egc *egc,
-                                           libxl__domain_suspend_state *dss);
+                                           libxl__domain_suspend_state *dsps);
 static void domain_suspend_callback_common_done(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss, int rc);
+                                libxl__domain_suspend_state *dsps, int rc);
 
-/* calls dss->callback_common_done when done */
+/* calls dsps->callback_common_done when done */
 void libxl__domain_suspend(libxl__egc *egc,
-                           libxl__domain_suspend_state *dss)
+                           libxl__domain_suspend_state *dsps)
 {
-    domain_suspend_callback_common(egc, dss);
+    domain_suspend_callback_common(egc, dsps);
 }
 
 static bool domain_suspend_pvcontrol_acked(const char *state) {
@@ -90,37 +147,37 @@  static bool domain_suspend_pvcontrol_acked(const char *state) {
     return strcmp(state,"suspend");
 }
 
-/* calls dss->callback_common_done when done */
+/* calls dsps->callback_common_done when done */
 static void domain_suspend_callback_common(libxl__egc *egc,
-                                           libxl__domain_suspend_state *dss)
+                                           libxl__domain_suspend_state *dsps)
 {
-    STATE_AO_GC(dss->ao);
+    STATE_AO_GC(dsps->ao);
     uint64_t hvm_s_state = 0, hvm_pvdrv = 0;
     int ret, rc;
 
     /* Convenience aliases */
-    const uint32_t domid = dss->domid;
+    const uint32_t domid = dsps->domid;
 
-    if (dss->hvm) {
+    if (dsps->hvm) {
         xc_hvm_param_get(CTX->xch, domid, HVM_PARAM_CALLBACK_IRQ, &hvm_pvdrv);
         xc_hvm_param_get(CTX->xch, domid, HVM_PARAM_ACPI_S_STATE, &hvm_s_state);
     }
 
-    if ((hvm_s_state == 0) && (dss->guest_evtchn.port >= 0)) {
+    if ((hvm_s_state == 0) && (dsps->guest_evtchn.port >= 0)) {
         LOG(DEBUG, "issuing %s suspend request via event channel",
-            dss->hvm ? "PVHVM" : "PV");
-        ret = xc_evtchn_notify(CTX->xce, dss->guest_evtchn.port);
+            dsps->hvm ? "PVHVM" : "PV");
+        ret = xc_evtchn_notify(CTX->xce, dsps->guest_evtchn.port);
         if (ret < 0) {
             LOG(ERROR, "xc_evtchn_notify failed ret=%d", ret);
             rc = ERROR_FAIL;
             goto err;
         }
 
-        dss->guest_evtchn.callback = domain_suspend_common_wait_guest_evtchn;
-        rc = libxl__ev_evtchn_wait(gc, &dss->guest_evtchn);
+        dsps->guest_evtchn.callback = domain_suspend_common_wait_guest_evtchn;
+        rc = libxl__ev_evtchn_wait(gc, &dsps->guest_evtchn);
         if (rc) goto err;
 
-        rc = libxl__ev_time_register_rel(ao, &dss->guest_timeout,
+        rc = libxl__ev_time_register_rel(ao, &dsps->guest_timeout,
                                          suspend_common_wait_guest_timeout,
                                          60*1000);
         if (rc) goto err;
@@ -128,7 +185,7 @@  static void domain_suspend_callback_common(libxl__egc *egc,
         return;
     }
 
-    if (dss->hvm && (!hvm_pvdrv || hvm_s_state)) {
+    if (dsps->hvm && (!hvm_pvdrv || hvm_s_state)) {
         LOG(DEBUG, "Calling xc_domain_shutdown on HVM domain");
         ret = xc_domain_shutdown(CTX->xch, domid, SHUTDOWN_suspend);
         if (ret < 0) {
@@ -137,55 +194,55 @@  static void domain_suspend_callback_common(libxl__egc *egc,
             goto err;
         }
         /* The guest does not (need to) respond to this sort of request. */
-        dss->guest_responded = 1;
-        domain_suspend_common_wait_guest(egc, dss);
+        dsps->guest_responded = 1;
+        domain_suspend_common_wait_guest(egc, dsps);
         return;
     }
 
     LOG(DEBUG, "issuing %s suspend request via XenBus control node",
-        dss->hvm ? "PVHVM" : "PV");
+        dsps->hvm ? "PVHVM" : "PV");
 
     libxl__domain_pvcontrol_write(gc, XBT_NULL, domid, "suspend");
 
-    dss->pvcontrol.path = libxl__domain_pvcontrol_xspath(gc, domid);
-    if (!dss->pvcontrol.path) { rc = ERROR_FAIL; goto err; }
+    dsps->pvcontrol.path = libxl__domain_pvcontrol_xspath(gc, domid);
+    if (!dsps->pvcontrol.path) { rc = ERROR_FAIL; goto err; }
 
-    dss->pvcontrol.ao = ao;
-    dss->pvcontrol.what = "guest acknowledgement of suspend request";
-    dss->pvcontrol.timeout_ms = 60 * 1000;
-    dss->pvcontrol.callback = domain_suspend_common_pvcontrol_suspending;
-    libxl__xswait_start(gc, &dss->pvcontrol);
+    dsps->pvcontrol.ao = ao;
+    dsps->pvcontrol.what = "guest acknowledgement of suspend request";
+    dsps->pvcontrol.timeout_ms = 60 * 1000;
+    dsps->pvcontrol.callback = domain_suspend_common_pvcontrol_suspending;
+    libxl__xswait_start(gc, &dsps->pvcontrol);
     return;
 
  err:
-    domain_suspend_common_done(egc, dss, rc);
+    domain_suspend_common_done(egc, dsps, rc);
 }
 
 static void domain_suspend_common_wait_guest_evtchn(libxl__egc *egc,
         libxl__ev_evtchn *evev)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(evev, *dss, guest_evtchn);
-    STATE_AO_GC(dss->ao);
+    libxl__domain_suspend_state *dsps = CONTAINER_OF(evev, *dsps, guest_evtchn);
+    STATE_AO_GC(dsps->ao);
     /* If we should be done waiting, suspend_common_wait_guest_check
      * will end up calling domain_suspend_common_guest_suspended or
      * domain_suspend_common_done, both of which cancel the evtchn
      * wait as needed.  So re-enable it now. */
-    libxl__ev_evtchn_wait(gc, &dss->guest_evtchn);
-    suspend_common_wait_guest_check(egc, dss);
+    libxl__ev_evtchn_wait(gc, &dsps->guest_evtchn);
+    suspend_common_wait_guest_check(egc, dsps);
 }
 
 static void domain_suspend_common_pvcontrol_suspending(libxl__egc *egc,
       libxl__xswait_state *xswa, int rc, const char *state)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(xswa, *dss, pvcontrol);
-    STATE_AO_GC(dss->ao);
+    libxl__domain_suspend_state *dsps = CONTAINER_OF(xswa, *dsps, pvcontrol);
+    STATE_AO_GC(dsps->ao);
     xs_transaction_t t = 0;
 
     if (!rc && !domain_suspend_pvcontrol_acked(state))
         /* keep waiting */
         return;
 
-    libxl__xswait_stop(gc, &dss->pvcontrol);
+    libxl__xswait_stop(gc, &dsps->pvcontrol);
 
     if (rc == ERROR_TIMEDOUT) {
         /*
@@ -228,56 +285,56 @@  static void domain_suspend_common_pvcontrol_suspending(libxl__egc *egc,
     LOG(DEBUG, "guest acknowledged suspend request");
 
     libxl__xs_transaction_abort(gc, &t);
-    dss->guest_responded = 1;
-    domain_suspend_common_wait_guest(egc,dss);
+    dsps->guest_responded = 1;
+    domain_suspend_common_wait_guest(egc,dsps);
     return;
 
  err:
     libxl__xs_transaction_abort(gc, &t);
-    domain_suspend_common_done(egc, dss, rc);
+    domain_suspend_common_done(egc, dsps, rc);
     return;
 }
 
 static void domain_suspend_common_wait_guest(libxl__egc *egc,
-                                             libxl__domain_suspend_state *dss)
+                                             libxl__domain_suspend_state *dsps)
 {
-    STATE_AO_GC(dss->ao);
+    STATE_AO_GC(dsps->ao);
     int rc;
 
     LOG(DEBUG, "wait for the guest to suspend");
 
-    rc = libxl__ev_xswatch_register(gc, &dss->guest_watch,
+    rc = libxl__ev_xswatch_register(gc, &dsps->guest_watch,
                                     suspend_common_wait_guest_watch,
                                     "@releaseDomain");
     if (rc) goto err;
 
-    rc = libxl__ev_time_register_rel(ao, &dss->guest_timeout,
+    rc = libxl__ev_time_register_rel(ao, &dsps->guest_timeout,
                                      suspend_common_wait_guest_timeout,
                                      60*1000);
     if (rc) goto err;
     return;
 
  err:
-    domain_suspend_common_done(egc, dss, rc);
+    domain_suspend_common_done(egc, dsps, rc);
 }
 
 static void suspend_common_wait_guest_watch(libxl__egc *egc,
       libxl__ev_xswatch *xsw, const char *watch_path, const char *event_path)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(xsw, *dss, guest_watch);
-    suspend_common_wait_guest_check(egc, dss);
+    libxl__domain_suspend_state *dsps = CONTAINER_OF(xsw, *dsps, guest_watch);
+    suspend_common_wait_guest_check(egc, dsps);
 }
 
 static void suspend_common_wait_guest_check(libxl__egc *egc,
-        libxl__domain_suspend_state *dss)
+        libxl__domain_suspend_state *dsps)
 {
-    STATE_AO_GC(dss->ao);
+    STATE_AO_GC(dsps->ao);
     xc_domaininfo_t info;
     int ret;
     int shutdown_reason;
 
     /* Convenience aliases */
-    const uint32_t domid = dss->domid;
+    const uint32_t domid = dsps->domid;
 
     ret = xc_domain_getinfolist(CTX->xch, domid, 1, &info);
     if (ret < 0) {
@@ -304,71 +361,73 @@  static void suspend_common_wait_guest_check(libxl__egc *egc,
     }
 
     LOG(DEBUG, "guest has suspended");
-    domain_suspend_common_guest_suspended(egc, dss);
+    domain_suspend_common_guest_suspended(egc, dsps);
     return;
 
  err:
-    domain_suspend_common_done(egc, dss, ERROR_FAIL);
+    domain_suspend_common_done(egc, dsps, ERROR_FAIL);
 }
 
 static void suspend_common_wait_guest_timeout(libxl__egc *egc,
       libxl__ev_time *ev, const struct timeval *requested_abs, int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(ev, *dss, guest_timeout);
-    STATE_AO_GC(dss->ao);
+    libxl__domain_suspend_state *dsps = CONTAINER_OF(ev, *dsps, guest_timeout);
+    STATE_AO_GC(dsps->ao);
     if (rc == ERROR_TIMEDOUT) {
         LOG(ERROR, "guest did not suspend, timed out");
         rc = ERROR_GUEST_TIMEDOUT;
     }
-    domain_suspend_common_done(egc, dss, rc);
+    domain_suspend_common_done(egc, dsps, rc);
 }
 
 static void domain_suspend_common_guest_suspended(libxl__egc *egc,
-                                         libxl__domain_suspend_state *dss)
+                                         libxl__domain_suspend_state *dsps)
 {
-    STATE_AO_GC(dss->ao);
+    STATE_AO_GC(dsps->ao);
     int rc;
 
-    libxl__ev_evtchn_cancel(gc, &dss->guest_evtchn);
-    libxl__ev_xswatch_deregister(gc, &dss->guest_watch);
-    libxl__ev_time_deregister(gc, &dss->guest_timeout);
+    libxl__ev_evtchn_cancel(gc, &dsps->guest_evtchn);
+    libxl__ev_xswatch_deregister(gc, &dsps->guest_watch);
+    libxl__ev_time_deregister(gc, &dsps->guest_timeout);
 
-    if (dss->hvm) {
-        rc = libxl__domain_suspend_device_model(gc, dss);
+    if (dsps->hvm) {
+        rc = libxl__domain_suspend_device_model(gc, dsps);
         if (rc) {
             LOG(ERROR, "libxl__domain_suspend_device_model failed ret=%d", rc);
-            domain_suspend_common_done(egc, dss, rc);
+            domain_suspend_common_done(egc, dsps, rc);
             return;
         }
     }
-    domain_suspend_common_done(egc, dss, 0);
+    domain_suspend_common_done(egc, dsps, 0);
 }
 
 static void domain_suspend_common_done(libxl__egc *egc,
-                                       libxl__domain_suspend_state *dss,
+                                       libxl__domain_suspend_state *dsps,
                                        int rc)
 {
     EGC_GC;
-    assert(!libxl__xswait_inuse(&dss->pvcontrol));
-    libxl__ev_evtchn_cancel(gc, &dss->guest_evtchn);
-    libxl__ev_xswatch_deregister(gc, &dss->guest_watch);
-    libxl__ev_time_deregister(gc, &dss->guest_timeout);
-    dss->callback_common_done(egc, dss, rc);
+    assert(!libxl__xswait_inuse(&dsps->pvcontrol));
+    libxl__ev_evtchn_cancel(gc, &dsps->guest_evtchn);
+    libxl__ev_xswatch_deregister(gc, &dsps->guest_watch);
+    libxl__ev_time_deregister(gc, &dsps->guest_timeout);
+    dsps->callback_common_done(egc, dsps, rc);
 }
 
 void libxl__domain_suspend_callback(void *data)
 {
     libxl__save_helper_state *shs = data;
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
+    libxl__domain_suspend_state *dsps = &dss->dsps;
 
-    dss->callback_common_done = domain_suspend_callback_common_done;
-    domain_suspend_callback_common(egc, dss);
+    dsps->callback_common_done = domain_suspend_callback_common_done;
+    domain_suspend_callback_common(egc, dsps);
 }
 
 static void domain_suspend_callback_common_done(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss, int rc)
+                                libxl__domain_suspend_state *dsps, int rc)
 {
+    libxl__domain_save_state *dss = CONTAINER_OF(dsps, *dss, dsps);
     dss->rc = rc;
     libxl__xc_domain_saverestore_async_callback_done(egc, &dss->sws.shs, !rc);
 }
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index 05537cc..93dd06c 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -3007,11 +3007,12 @@  static inline bool libxl__conversion_helper_inuse
  */
 
 typedef struct libxl__domain_suspend_state libxl__domain_suspend_state;
+typedef struct libxl__domain_save_state libxl__domain_save_state;
 
-typedef void libxl__domain_suspend_cb(libxl__egc*,
-                                      libxl__domain_suspend_state*, int rc);
+typedef void libxl__domain_save_cb(libxl__egc*,
+                                   libxl__domain_save_state*, int rc);
 typedef void libxl__save_device_model_cb(libxl__egc*,
-                                         libxl__domain_suspend_state*, int rc);
+                                         libxl__domain_save_state*, int rc);
 
 /* State for writing a libxl migration v2 stream */
 typedef struct libxl__stream_write_state libxl__stream_write_state;
@@ -3020,7 +3021,7 @@  typedef void (*sws_record_done_cb)(libxl__egc *egc,
 struct libxl__stream_write_state {
     /* filled by the user */
     libxl__ao *ao;
-    libxl__domain_suspend_state *dss;
+    libxl__domain_save_state *dss;
     int fd;
     void (*completion_callback)(libxl__egc *egc,
                                 libxl__stream_write_state *sws,
@@ -3074,9 +3075,32 @@  typedef struct libxl__logdirty_switch {
 } libxl__logdirty_switch;
 
 struct libxl__domain_suspend_state {
+    /* set by caller of libxl__domain_suspend_init */
+    libxl__ao *ao;
+    uint32_t domid;
+
+    /* private */
+    int hvm;
+
+    libxl__ev_evtchn guest_evtchn;
+    int guest_evtchn_lockfd;
+    int guest_responded;
+
+    libxl__xswait_state pvcontrol;
+    libxl__ev_xswatch guest_watch;
+    libxl__ev_time guest_timeout;
+
+    const char *dm_savefile;
+    void (*callback_common_done)(libxl__egc*,
+                                 struct libxl__domain_suspend_state*, int ok);
+};
+int libxl__domain_suspend_init(libxl__egc *egc,
+                               libxl__domain_suspend_state *dsps);
+
+struct libxl__domain_save_state {
     /* set by caller of libxl__domain_save */
     libxl__ao *ao;
-    libxl__domain_suspend_cb *callback;
+    libxl__domain_save_cb *callback;
 
     uint32_t domid;
     int fd;
@@ -3087,22 +3111,14 @@  struct libxl__domain_suspend_state {
     const libxl_domain_remus_info *remus;
     /* private */
     int rc;
-    libxl__ev_evtchn guest_evtchn;
-    int guest_evtchn_lockfd;
     int hvm;
     int xcflags;
-    int guest_responded;
-    libxl__xswait_state pvcontrol;
-    libxl__ev_xswatch guest_watch;
-    libxl__ev_time guest_timeout;
-    const char *dm_savefile;
+    libxl__domain_suspend_state dsps;
     libxl__remus_devices_state rds;
     libxl__ev_time checkpoint_timeout; /* used for Remus checkpoint */
     int interval; /* checkpoint interval (for Remus) */
     libxl__stream_write_state sws;
     libxl__logdirty_switch logdirty;
-    void (*callback_common_done)(libxl__egc*,
-                                 struct libxl__domain_suspend_state*, int ok);
     /* private for libxl__domain_save_device_model */
     libxl__save_device_model_cb *save_dm_callback;
     libxl__datacopier_state save_dm_datacopier;
@@ -3446,12 +3462,12 @@  struct libxl__domain_create_state {
 
 /* calls dss->callback when done */
 _hidden void libxl__domain_save(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss);
+                                libxl__domain_save_state *dss);
 
 
 /* calls libxl__xc_domain_suspend_done when done */
 _hidden void libxl__xc_domain_save(libxl__egc *egc,
-                                   libxl__domain_suspend_state *dss,
+                                   libxl__domain_save_state *dss,
                                    libxl__save_helper_state *shs);
 /* If rc==0 then retval is the return value from xc_domain_save
  * and errnoval is the errno value it provided.
@@ -3469,7 +3485,7 @@  void libxl__xc_domain_saverestore_async_callback_done(libxl__egc *egc,
 
 _hidden void libxl__domain_suspend_common_switch_qemu_logdirty
                                (int domid, unsigned int enable, void *data);
-_hidden int libxl__save_emulator_xenstore_data(libxl__domain_suspend_state *dss,
+_hidden int libxl__save_emulator_xenstore_data(libxl__domain_save_state *dss,
                                                char **buf, uint32_t *len);
 _hidden int libxl__restore_emulator_xenstore_data
     (libxl__domain_create_state *dcs, const char *ptr, uint32_t size);
@@ -3497,13 +3513,13 @@  static inline bool libxl__save_helper_inuse(const libxl__save_helper_state *shs)
 
 /* Each time the dm needs to be saved, we must call suspend and then save */
 _hidden int libxl__domain_suspend_device_model(libxl__gc *gc,
-                                           libxl__domain_suspend_state *dss);
+                                           libxl__domain_suspend_state *dsps);
 
 _hidden const char *libxl__device_model_savefile(libxl__gc *gc, uint32_t domid);
 
-/* calls dss->callback_common_done when done */
+/* calls dsps->callback_common_done when done */
 _hidden void libxl__domain_suspend(libxl__egc *egc,
-                                   libxl__domain_suspend_state *dss);
+                                   libxl__domain_suspend_state *dsps);
 /* used by libxc to suspend the guest during migration */
 _hidden void libxl__domain_suspend_callback(void *data);
 
@@ -3513,9 +3529,9 @@  _hidden void libxl__remus_domain_resume_callback(void *data);
 _hidden void libxl__remus_domain_save_checkpoint_callback(void *data);
 /* Remus setup and teardown*/
 _hidden void libxl__remus_setup(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss);
+                                libxl__domain_save_state *dss);
 _hidden void libxl__remus_teardown(libxl__egc *egc,
-                                   libxl__domain_suspend_state *dss,
+                                   libxl__domain_save_state *dss,
                                    int rc);
 /* Remus callbacks for restore */
 _hidden void libxl__remus_domain_restore_checkpoint_callback(void *data);
diff --git a/tools/libxl/libxl_netbuffer.c b/tools/libxl/libxl_netbuffer.c
index 107e867..c245a4e 100644
--- a/tools/libxl/libxl_netbuffer.c
+++ b/tools/libxl/libxl_netbuffer.c
@@ -41,7 +41,7 @@  int libxl__netbuffer_enabled(libxl__gc *gc)
 int init_subkind_nic(libxl__remus_devices_state *rds)
 {
     int rc, ret;
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
 
     STATE_AO_GC(rds->ao);
 
diff --git a/tools/libxl/libxl_remus.c b/tools/libxl/libxl_remus.c
index e3caf7d..fae2120 100644
--- a/tools/libxl/libxl_remus.c
+++ b/tools/libxl/libxl_remus.c
@@ -28,7 +28,7 @@  static void remus_checkpoint_stream_written(
     libxl__egc *egc, libxl__stream_write_state *sws, int rc);
 
 void libxl__remus_setup(libxl__egc *egc,
-                        libxl__domain_suspend_state *dss)
+                        libxl__domain_save_state *dss)
 {
     /* Convenience aliases */
     libxl__remus_devices_state *const rds = &dss->rds;
@@ -63,7 +63,7 @@  out:
 static void remus_setup_done(libxl__egc *egc,
                              libxl__remus_devices_state *rds, int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
     STATE_AO_GC(dss->ao);
 
     if (!rc) {
@@ -80,7 +80,7 @@  static void remus_setup_done(libxl__egc *egc,
 static void remus_setup_failed(libxl__egc *egc,
                                libxl__remus_devices_state *rds, int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
     STATE_AO_GC(dss->ao);
 
     if (rc)
@@ -94,7 +94,7 @@  static void remus_teardown_done(libxl__egc *egc,
                                 libxl__remus_devices_state *rds,
                                 int rc);
 void libxl__remus_teardown(libxl__egc *egc,
-                           libxl__domain_suspend_state *dss,
+                           libxl__domain_save_state *dss,
                            int rc)
 {
     EGC_GC;
@@ -109,7 +109,7 @@  static void remus_teardown_done(libxl__egc *egc,
                                 libxl__remus_devices_state *rds,
                                 int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
     STATE_AO_GC(dss->ao);
 
     if (rc)
@@ -122,7 +122,7 @@  static void remus_teardown_done(libxl__egc *egc,
 /*---------------------- remus callbacks (save) -----------------------*/
 
 static void remus_domain_suspend_callback_common_done(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss, int ok);
+                                libxl__domain_suspend_state *dsps, int ok);
 static void remus_devices_postsuspend_cb(libxl__egc *egc,
                                          libxl__remus_devices_state *rds,
                                          int rc);
@@ -134,15 +134,18 @@  void libxl__remus_domain_suspend_callback(void *data)
 {
     libxl__save_helper_state *shs = data;
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
+    libxl__domain_suspend_state *dsps = &dss->dsps;
 
-    dss->callback_common_done = remus_domain_suspend_callback_common_done;
-    libxl__domain_suspend(egc, dss);
+    dsps->callback_common_done = remus_domain_suspend_callback_common_done;
+    libxl__domain_suspend(egc, dsps);
 }
 
 static void remus_domain_suspend_callback_common_done(libxl__egc *egc,
-                                libxl__domain_suspend_state *dss, int rc)
+                                libxl__domain_suspend_state *dsps, int rc)
 {
+    libxl__domain_save_state *dss = CONTAINER_OF(dsps, *dss, dsps);
+
     if (rc)
         goto out;
 
@@ -160,7 +163,7 @@  static void remus_devices_postsuspend_cb(libxl__egc *egc,
                                          libxl__remus_devices_state *rds,
                                          int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
 
     if (rc)
         goto out;
@@ -177,7 +180,7 @@  void libxl__remus_domain_resume_callback(void *data)
 {
     libxl__save_helper_state *shs = data;
     libxl__egc *egc = shs->egc;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
     STATE_AO_GC(dss->ao);
 
     libxl__remus_devices_state *const rds = &dss->rds;
@@ -189,7 +192,7 @@  static void remus_devices_preresume_cb(libxl__egc *egc,
                                        libxl__remus_devices_state *rds,
                                        int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
     STATE_AO_GC(dss->ao);
 
     if (rc)
@@ -220,7 +223,7 @@  static void remus_next_checkpoint(libxl__egc *egc, libxl__ev_time *ev,
 void libxl__remus_domain_save_checkpoint_callback(void *data)
 {
     libxl__save_helper_state *shs = data;
-    libxl__domain_suspend_state *dss = shs->caller_state;
+    libxl__domain_save_state *dss = shs->caller_state;
     libxl__egc *egc = shs->egc;
     STATE_AO_GC(dss->ao);
 
@@ -230,7 +233,7 @@  void libxl__remus_domain_save_checkpoint_callback(void *data)
 static void remus_checkpoint_stream_written(
     libxl__egc *egc, libxl__stream_write_state *sws, int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(sws, *dss, sws);
+    libxl__domain_save_state *dss = CONTAINER_OF(sws, *dss, sws);
 
     /* Convenience aliases */
     libxl__remus_devices_state *const rds = &dss->rds;
@@ -255,7 +258,7 @@  static void remus_devices_commit_cb(libxl__egc *egc,
                                     libxl__remus_devices_state *rds,
                                     int rc)
 {
-    libxl__domain_suspend_state *dss = CONTAINER_OF(rds, *dss, rds);
+    libxl__domain_save_state *dss = CONTAINER_OF(rds, *dss, rds);
 
     STATE_AO_GC(dss->ao);
 
@@ -290,7 +293,7 @@  static void remus_next_checkpoint(libxl__egc *egc, libxl__ev_time *ev,
                                   const struct timeval *requested_abs,
                                   int rc)
 {
-    libxl__domain_suspend_state *dss =
+    libxl__domain_save_state *dss =
                             CONTAINER_OF(ev, *dss, checkpoint_timeout);
 
     STATE_AO_GC(dss->ao);
diff --git a/tools/libxl/libxl_save_callout.c b/tools/libxl/libxl_save_callout.c
index 3af99af..2d06b42 100644
--- a/tools/libxl/libxl_save_callout.c
+++ b/tools/libxl/libxl_save_callout.c
@@ -75,7 +75,7 @@  void libxl__xc_domain_restore(libxl__egc *egc, libxl__domain_create_state *dcs,
                argnums, ARRAY_SIZE(argnums));
 }
 
-void libxl__xc_domain_save(libxl__egc *egc, libxl__domain_suspend_state *dss,
+void libxl__xc_domain_save(libxl__egc *egc, libxl__domain_save_state *dss,
                            libxl__save_helper_state *shs)
 {
     STATE_AO_GC(dss->ao);
diff --git a/tools/libxl/libxl_stream_write.c b/tools/libxl/libxl_stream_write.c
index ee9c53a..c408ab1 100644
--- a/tools/libxl/libxl_stream_write.c
+++ b/tools/libxl/libxl_stream_write.c
@@ -216,7 +216,7 @@  void libxl__stream_write_start(libxl__egc *egc,
                                libxl__stream_write_state *stream)
 {
     libxl__datacopier_state *dc = &stream->dc;
-    libxl__domain_suspend_state *dss = stream->dss;
+    libxl__domain_save_state *dss = stream->dss;
     STATE_AO_GC(stream->ao);
     struct libxl__sr_hdr hdr;
     int rc = 0;
@@ -324,7 +324,7 @@  static void libxc_header_done(libxl__egc *egc,
 void libxl__xc_domain_save_done(libxl__egc *egc, void *dss_void,
                                 int rc, int retval, int errnoval)
 {
-    libxl__domain_suspend_state *dss = dss_void;
+    libxl__domain_save_state *dss = dss_void;
     libxl__stream_write_state *stream = &dss->sws;
     STATE_AO_GC(dss->ao);
 
@@ -333,10 +333,10 @@  void libxl__xc_domain_save_done(libxl__egc *egc, void *dss_void,
 
     if (retval) {
         LOGEV(ERROR, errnoval, "saving domain: %s",
-              dss->guest_responded ?
+              dss->dsps.guest_responded ?
               "domain responded to suspend request" :
               "domain did not respond to suspend request");
-        if (!dss->guest_responded)
+        if (!dss->dsps.guest_responded)
             rc = ERROR_GUEST_TIMEDOUT;
         else if (dss->rc)
             rc = dss->rc;
@@ -365,7 +365,7 @@  void libxl__xc_domain_save_done(libxl__egc *egc, void *dss_void,
 static void write_emulator_xenstore_record(libxl__egc *egc,
                                            libxl__stream_write_state *stream)
 {
-    libxl__domain_suspend_state *dss = stream->dss;
+    libxl__domain_save_state *dss = stream->dss;
     STATE_AO_GC(stream->ao);
     struct libxl__sr_rec_hdr rec;
     int rc;
@@ -404,7 +404,7 @@  static void write_emulator_xenstore_record(libxl__egc *egc,
 static void emulator_xenstore_record_done(libxl__egc *egc,
                                           libxl__stream_write_state *stream)
 {
-    libxl__domain_suspend_state *dss = stream->dss;
+    libxl__domain_save_state *dss = stream->dss;
 
     if (dss->type == LIBXL_DOMAIN_TYPE_HVM)
         write_emulator_context_record(egc, stream);
@@ -419,7 +419,7 @@  static void emulator_xenstore_record_done(libxl__egc *egc,
 static void write_emulator_context_record(libxl__egc *egc,
                                           libxl__stream_write_state *stream)
 {
-    libxl__domain_suspend_state *dss = stream->dss;
+    libxl__domain_save_state *dss = stream->dss;
     libxl__datacopier_state *dc = &stream->emu_dc;
     STATE_AO_GC(stream->ao);
     struct libxl__sr_rec_hdr *rec = &stream->emu_rec_hdr;
@@ -434,7 +434,7 @@  static void write_emulator_context_record(libxl__egc *egc,
     }
 
     /* Convenience aliases */
-    const char *const filename = dss->dm_savefile;
+    const char *const filename = dss->dsps.dm_savefile;
 
     libxl__carefd_begin();
     int readfd = open(filename, O_RDONLY);