migration: Create multipage support

We only create/destry the page list here.  We will use it later.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

migration/ram.c

@@ -517,6 +517,20 @@ typedef struct {
     uint8_t id;
 } __attribute__((packed)) MultiFDInit_t;
 
+typedef struct {
+    /* number of used pages */
+    uint32_t used;
+    /* number of allocated pages */
+    uint32_t allocated;
+    /* global number of generated multifd packets */
+    uint64_t packet_num;
+    /* offset of each page */
+    ram_addr_t *offset;
+    /* pointer to each page */
+    struct iovec *iov;
+    RAMBlock *block;
+} MultiFDPages_t;
+
 typedef struct {
     /* this fields are not changed once the thread is created */
     /* channel number */
@@ -535,6 +549,8 @@ typedef struct {
     bool running;
     /* should this thread finish */
     bool quit;
+    /* array of pages to sent */
+    MultiFDPages_t *pages;
 }  MultiFDSendParams;
 
 typedef struct {
@@ -555,6 +571,8 @@ typedef struct {
     bool running;
     /* should this thread finish */
     bool quit;
+    /* array of pages to receive */
+    MultiFDPages_t *pages;
 } MultiFDRecvParams;
 
 static int multifd_send_initial_packet(MultiFDSendParams *p, Error **errp)
@@ -619,10 +637,36 @@ static int multifd_recv_initial_packet(QIOChannel *c, Error **errp)
     return msg.id;
 }
 
+static MultiFDPages_t *multifd_pages_init(size_t size)
+{
+    MultiFDPages_t *pages = g_new0(MultiFDPages_t, 1);
+
+    pages->allocated = size;
+    pages->iov = g_new0(struct iovec, size);
+    pages->offset = g_new0(ram_addr_t, size);
+
+    return pages;
+}
+
+static void multifd_pages_clear(MultiFDPages_t *pages)
+{
+    pages->used = 0;
+    pages->allocated = 0;
+    pages->packet_num = 0;
+    pages->block = NULL;
+    g_free(pages->iov);
+    pages->iov = NULL;
+    g_free(pages->offset);
+    pages->offset = NULL;
+    g_free(pages);
+}
+
 struct {
     MultiFDSendParams *params;
     /* number of created threads */
     int count;
+    /* array of pages to sent */
+    MultiFDPages_t *pages;
 } *multifd_send_state;
 
 static void multifd_send_terminate_threads(Error *err)
@@ -672,9 +716,13 @@ int multifd_save_cleanup(Error **errp)
         qemu_sem_destroy(&p->sem);
         g_free(p->name);
         p->name = NULL;
+        multifd_pages_clear(p->pages);
+        p->pages = NULL;
     }
     g_free(multifd_send_state->params);
     multifd_send_state->params = NULL;
+    multifd_pages_clear(multifd_send_state->pages);
+    multifd_send_state->pages = NULL;
     g_free(multifd_send_state);
     multifd_send_state = NULL;
     return ret;
@@ -735,6 +783,7 @@ static void multifd_new_send_channel_async(QIOTask *task, gpointer opaque)
 int multifd_save_setup(void)
 {
     int thread_count;
+    uint32_t page_count = migrate_multifd_page_count();
     uint8_t i;
 
     if (!migrate_use_multifd()) {
@@ -744,6 +793,8 @@ int multifd_save_setup(void)
     multifd_send_state = g_malloc0(sizeof(*multifd_send_state));
     multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
     atomic_set(&multifd_send_state->count, 0);
+    multifd_send_state->pages = multifd_pages_init(page_count);
+
     for (i = 0; i < thread_count; i++) {
         MultiFDSendParams *p = &multifd_send_state->params[i];
 
@@ -751,6 +802,7 @@ int multifd_save_setup(void)
         qemu_sem_init(&p->sem, 0);
         p->quit = false;
         p->id = i;
+        p->pages = multifd_pages_init(page_count);
         p->name = g_strdup_printf("multifdsend_%d", i);
         socket_send_channel_create(multifd_new_send_channel_async, p);
     }
@@ -808,6 +860,8 @@ int multifd_load_cleanup(Error **errp)
         qemu_sem_destroy(&p->sem);
         g_free(p->name);
         p->name = NULL;
+        multifd_pages_clear(p->pages);
+        p->pages = NULL;
     }
     g_free(multifd_recv_state->params);
     multifd_recv_state->params = NULL;
@@ -841,6 +895,7 @@ static void *multifd_recv_thread(void *opaque)
 int multifd_load_setup(void)
 {
     int thread_count;
+    uint32_t page_count = migrate_multifd_page_count();
     uint8_t i;
 
     if (!migrate_use_multifd()) {
@@ -850,6 +905,7 @@ int multifd_load_setup(void)
     multifd_recv_state = g_malloc0(sizeof(*multifd_recv_state));
     multifd_recv_state->params = g_new0(MultiFDRecvParams, thread_count);
     atomic_set(&multifd_recv_state->count, 0);
+
     for (i = 0; i < thread_count; i++) {
         MultiFDRecvParams *p = &multifd_recv_state->params[i];
 
@@ -857,6 +913,7 @@ int multifd_load_setup(void)
         qemu_sem_init(&p->sem, 0);
         p->quit = false;
         p->id = i;
+        p->pages = multifd_pages_init(page_count);
         p->name = g_strdup_printf("multifdrecv_%d", i);
     }
     return 0;