1 files changed, 61 insertions, 13 deletions

diff --git a/migration/multifd.h b/migration/multifd.h
index cf408ff721..2d337e7b3b 100644
--- a/migration/multifd.h
+++ b/migration/multifd.h
@@ -62,6 +62,12 @@ MultiFDRecvData *multifd_get_recv_data(void);
 #define MULTIFD_FLAG_UADK (8 << 1)
 #define MULTIFD_FLAG_QATZIP (16 << 1)
 
+/*
+ * If set it means that this packet contains device state
+ * (MultiFDPacketDeviceState_t), not RAM data (MultiFDPacket_t).
+ */
+#define MULTIFD_FLAG_DEVICE_STATE (32 << 1)
+
 /* This value needs to be a multiple of qemu_target_page_size() */
 #define MULTIFD_PACKET_SIZE (512 * 1024)
 
@@ -69,6 +75,11 @@ typedef struct {
     uint32_t magic;
     uint32_t version;
     uint32_t flags;
+} __attribute__((packed)) MultiFDPacketHdr_t;
+
+typedef struct {
+    MultiFDPacketHdr_t hdr;
+
     /* maximum number of allocated pages */
     uint32_t pages_alloc;
     /* non zero pages */
@@ -90,13 +101,27 @@ typedef struct {
 } __attribute__((packed)) MultiFDPacket_t;
 
 typedef struct {
+    MultiFDPacketHdr_t hdr;
+
+    char idstr[256];
+    uint32_t instance_id;
+
+    /* size of the next packet that contains the actual data */
+    uint32_t next_packet_size;
+} __attribute__((packed)) MultiFDPacketDeviceState_t;
+
+typedef struct {
     /* number of used pages */
     uint32_t num;
     /* number of normal pages */
     uint32_t normal_num;
+    /*
+     * Pointer to the ramblock.  NOTE: it's caller's responsibility to make
+     * sure the pointer is always valid!
+     */
     RAMBlock *block;
-    /* offset of each page */
-    ram_addr_t offset[];
+    /* offset array of each page, managed by multifd */
+    ram_addr_t *offset;
 } MultiFDPages_t;
 
 struct MultiFDRecvData {
@@ -106,13 +131,22 @@ struct MultiFDRecvData {
     off_t file_offset;
 };
 
+typedef struct {
+    char *idstr;
+    uint32_t instance_id;
+    char *buf;
+    size_t buf_len;
+} MultiFDDeviceState_t;
+
 typedef enum {
     MULTIFD_PAYLOAD_NONE,
     MULTIFD_PAYLOAD_RAM,
+    MULTIFD_PAYLOAD_DEVICE_STATE,
 } MultiFDPayloadType;
 
-typedef union MultiFDPayload {
+typedef struct MultiFDPayload {
     MultiFDPages_t ram;
+    MultiFDDeviceState_t device_state;
 } MultiFDPayload;
 
 struct MultiFDSendData {
@@ -125,9 +159,17 @@ static inline bool multifd_payload_empty(MultiFDSendData *data)
     return data->type == MULTIFD_PAYLOAD_NONE;
 }
 
+static inline bool multifd_payload_device_state(MultiFDSendData *data)
+{
+    return data->type == MULTIFD_PAYLOAD_DEVICE_STATE;
+}
+
 static inline void multifd_set_payload_type(MultiFDSendData *data,
                                             MultiFDPayloadType type)
 {
+    assert(multifd_payload_empty(data));
+    assert(type != MULTIFD_PAYLOAD_NONE);
+
     data->type = type;
 }
 
@@ -174,8 +216,9 @@ typedef struct {
 
     /* thread local variables. No locking required */
 
-    /* pointer to the packet */
+    /* pointers to the possible packet types */
     MultiFDPacket_t *packet;
+    MultiFDPacketDeviceState_t *packet_device_state;
     /* size of the next packet that contains pages */
     uint32_t next_packet_size;
     /* packets sent through this channel */
@@ -222,8 +265,9 @@ typedef struct {
 
     /* thread local variables. No locking required */
 
-    /* pointer to the packet */
+    /* pointers to the possible packet types */
     MultiFDPacket_t *packet;
+    MultiFDPacketDeviceState_t *packet_dev_state;
     /* size of the next packet that contains pages */
     uint32_t next_packet_size;
     /* packets received through this channel */
@@ -333,16 +377,11 @@ bool multifd_send_prepare_common(MultiFDSendParams *p);
 void multifd_send_zero_page_detect(MultiFDSendParams *p);
 void multifd_recv_zero_page_process(MultiFDRecvParams *p);
 
-static inline void multifd_send_prepare_header(MultiFDSendParams *p)
-{
-    p->iov[0].iov_len = p->packet_len;
-    p->iov[0].iov_base = p->packet;
-    p->iovs_num++;
-}
-
 void multifd_channel_connect(MultiFDSendParams *p, QIOChannel *ioc);
 bool multifd_send(MultiFDSendData **send_data);
 MultiFDSendData *multifd_send_data_alloc(void);
+void multifd_send_data_clear(MultiFDSendData *data);
+void multifd_send_data_free(MultiFDSendData *data);
 
 static inline uint32_t multifd_ram_page_size(void)
 {
@@ -359,7 +398,16 @@ void multifd_ram_save_cleanup(void);
 int multifd_ram_flush_and_sync(QEMUFile *f);
 bool multifd_ram_sync_per_round(void);
 bool multifd_ram_sync_per_section(void);
-size_t multifd_ram_payload_size(void);
+void multifd_ram_payload_alloc(MultiFDPages_t *pages);
+void multifd_ram_payload_free(MultiFDPages_t *pages);
 void multifd_ram_fill_packet(MultiFDSendParams *p);
 int multifd_ram_unfill_packet(MultiFDRecvParams *p, Error **errp);
+
+void multifd_send_data_clear_device_state(MultiFDDeviceState_t *device_state);
+
+void multifd_device_state_send_setup(void);
+void multifd_device_state_send_cleanup(void);
+
+void multifd_device_state_send_prepare(MultiFDSendParams *p);
+
 #endif