From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Notify the vhost-user client on reception of the 'postcopy-listen'
event from the source.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
contrib/libvhost-user/libvhost-user.c | 19 +++++++++++++++++++
contrib/libvhost-user/libvhost-user.h | 2 ++
docs/interop/vhost-user.txt | 6 ++++++
hw/virtio/trace-events | 3 +++
hw/virtio/vhost-user.c | 34 ++++++++++++++++++++++++++++++++++
migration/postcopy-ram.h | 1 +
migration/savevm.c | 7 +++++++
7 files changed, 72 insertions(+)
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
index 0b563fc5ae..beec7695a8 100644
--- a/contrib/libvhost-user/libvhost-user.c
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -98,6 +98,7 @@ vu_request_to_string(unsigned int req)
REQ(VHOST_USER_GET_CONFIG),
REQ(VHOST_USER_SET_CONFIG),
REQ(VHOST_USER_POSTCOPY_ADVISE),
+ REQ(VHOST_USER_POSTCOPY_LISTEN),
REQ(VHOST_USER_MAX),
};
#undef REQ
@@ -933,6 +934,22 @@ out:
return true; /* = send a reply */
}
+static bool
+vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg)
+{
+ vmsg->payload.u64 = -1;
+ vmsg->size = sizeof(vmsg->payload.u64);
+
+ if (dev->nregions) {
+ vu_panic(dev, "Regions already registered at postcopy-listen");
+ return true;
+ }
+ dev->postcopy_listening = true;
+
+ vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK;
+ vmsg->payload.u64 = 0; /* Success */
+ return true;
+}
static bool
vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
{
@@ -1006,6 +1023,8 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
break;
case VHOST_USER_POSTCOPY_ADVISE:
return vu_set_postcopy_advise(dev, vmsg);
+ case VHOST_USER_POSTCOPY_LISTEN:
+ return vu_set_postcopy_listen(dev, vmsg);
default:
vmsg_close_fds(vmsg);
vu_panic(dev, "Unhandled request: %d", vmsg->request);
diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h
index bb33b33f3b..fcba53c3c3 100644
--- a/contrib/libvhost-user/libvhost-user.h
+++ b/contrib/libvhost-user/libvhost-user.h
@@ -83,6 +83,7 @@ typedef enum VhostUserRequest {
VHOST_USER_GET_CONFIG = 24,
VHOST_USER_SET_CONFIG = 25,
VHOST_USER_POSTCOPY_ADVISE = 26,
+ VHOST_USER_POSTCOPY_LISTEN = 27,
VHOST_USER_MAX
} VhostUserRequest;
@@ -282,6 +283,7 @@ struct VuDev {
/* Postcopy data */
int postcopy_ufd;
+ bool postcopy_listening;
};
typedef struct VuVirtqElement {
diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt
index 621543e654..bdec9ec0e8 100644
--- a/docs/interop/vhost-user.txt
+++ b/docs/interop/vhost-user.txt
@@ -682,6 +682,12 @@ Master message types
the slave must open a userfaultfd for later use.
Note that at this stage the migration is still in precopy mode.
+ * VHOST_USER_POSTCOPY_LISTEN
+ Id: 27
+ Master payload: N/A
+
+ Master advises slave that a transition to postcopy mode has happened.
+
Slave message types
-------------------
diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 742ff0f90b..06ec03d6e7 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -6,6 +6,9 @@ vhost_region_add_section(const char *name, uint64_t gpa, uint64_t size, uint64_t
vhost_region_add_section_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx64
vhost_section(const char *name, int r) "%s:%d"
+# hw/virtio/vhost-user.c
+vhost_user_postcopy_listen(void) ""
+
# hw/virtio/virtio.c
virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned out_num) "elem %p size %zd in_num %u out_num %u"
virtqueue_fill(void *vq, const void *elem, unsigned int len, unsigned int idx) "vq %p elem %p len %u idx %u"
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index dd4eb50668..ec6a4a82fd 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -19,6 +19,7 @@
#include "qemu/sockets.h"
#include "migration/migration.h"
#include "migration/postcopy-ram.h"
+#include "trace.h"
#include <sys/ioctl.h>
#include <sys/socket.h>
@@ -76,6 +77,7 @@ typedef enum VhostUserRequest {
VHOST_USER_GET_CONFIG = 24,
VHOST_USER_SET_CONFIG = 25,
VHOST_USER_POSTCOPY_ADVISE = 26,
+ VHOST_USER_POSTCOPY_LISTEN = 27,
VHOST_USER_MAX
} VhostUserRequest;
@@ -157,6 +159,8 @@ struct vhost_user {
int slave_fd;
NotifierWithReturn postcopy_notifier;
struct PostCopyFD postcopy_fd;
+ /* True once we've entered postcopy_listen */
+ bool postcopy_listen;
};
static bool ioeventfd_enabled(void)
@@ -843,6 +847,33 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
return 0;
}
+/*
+ * Called at the switch to postcopy on reception of the 'listen' command.
+ */
+static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp)
+{
+ struct vhost_user *u = dev->opaque;
+ int ret;
+ VhostUserMsg msg = {
+ .hdr.request = VHOST_USER_POSTCOPY_LISTEN,
+ .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
+ };
+ u->postcopy_listen = true;
+ trace_vhost_user_postcopy_listen();
+ if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
+ error_setg(errp, "Failed to send postcopy_listen to vhost");
+ return -1;
+ }
+
+ ret = process_message_reply(dev, &msg);
+ if (ret) {
+ error_setg(errp, "Failed to receive reply to postcopy_listen");
+ return ret;
+ }
+
+ return 0;
+}
+
static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
void *opaque)
{
@@ -865,6 +896,9 @@ static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
case POSTCOPY_NOTIFY_INBOUND_ADVISE:
return vhost_user_postcopy_advise(dev, pnd->errp);
+ case POSTCOPY_NOTIFY_INBOUND_LISTEN:
+ return vhost_user_postcopy_listen(dev, pnd->errp);
+
default:
/* We ignore notifications we don't know */
break;
diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h
index 23efbdf346..dbc2ee1f2b 100644
--- a/migration/postcopy-ram.h
+++ b/migration/postcopy-ram.h
@@ -129,6 +129,7 @@ void postcopy_infrastructure_init(void);
enum PostcopyNotifyReason {
POSTCOPY_NOTIFY_PROBE = 0,
POSTCOPY_NOTIFY_INBOUND_ADVISE,
+ POSTCOPY_NOTIFY_INBOUND_LISTEN,
};
struct PostcopyNotifyData {
diff --git a/migration/savevm.c b/migration/savevm.c
index 9840bcaac9..fa779232cc 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -1614,6 +1614,8 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis)
{
PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING);
trace_loadvm_postcopy_handle_listen();
+ Error *local_err = NULL;
+
if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) {
error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps);
return -1;
@@ -1639,6 +1641,11 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis)
}
}
+ if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_LISTEN, &local_err)) {
+ error_report_err(local_err);
+ return -1;
+ }
+
if (mis->have_listen_thread) {
error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread");
return -1;
--
2.14.3