multifd: Create page_count fields into both MultiFD{Recv,Send}Params

We were recalculating it left and right.  We plan to change that
values on next patches.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Leonardo Bras <leobras@redhat.com>

migration/multifd.c

@@ -279,7 +279,6 @@ static void multifd_send_fill_packet(MultiFDSendParams *p)
 static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp)
 {
     MultiFDPacket_t *packet = p->packet;
-    uint32_t page_count = MULTIFD_PACKET_SIZE / p->page_size;
     RAMBlock *block;
     int i;
 
@@ -306,10 +305,10 @@ static int multifd_recv_unfill_packet(MultiFDRecvParams *p, Error **errp)
      * If we received a packet that is 100 times bigger than expected
      * just stop migration.  It is a magic number.
      */
-    if (packet->pages_alloc > page_count) {
+    if (packet->pages_alloc > p->page_count) {
         error_setg(errp, "multifd: received packet "
                    "with size %u and expected a size of %u",
-                   packet->pages_alloc, page_count) ;
+                   packet->pages_alloc, p->page_count) ;
         return -1;
     }
 
@@ -944,6 +943,7 @@ int multifd_save_setup(Error **errp)
         p->iov = g_new0(struct iovec, page_count + 1);
         p->normal = g_new0(ram_addr_t, page_count);
         p->page_size = qemu_target_page_size();
+        p->page_count = page_count;
 
         if (migrate_use_zero_copy_send()) {
             p->write_flags = QIO_CHANNEL_WRITE_FLAG_ZERO_COPY;
@@ -1191,6 +1191,7 @@ int multifd_load_setup(Error **errp)
         p->name = g_strdup_printf("multifdrecv_%d", i);
         p->iov = g_new0(struct iovec, page_count);
         p->normal = g_new0(ram_addr_t, page_count);
+        p->page_count = page_count;
         p->page_size = qemu_target_page_size();
     }
 

migration/multifd.h

@@ -82,6 +82,8 @@ typedef struct {
     uint32_t packet_len;
     /* guest page size */
     uint32_t page_size;
+    /* number of pages in a full packet */
+    uint32_t page_count;
     /* multifd flags for sending ram */
     int write_flags;
 
@@ -147,6 +149,8 @@ typedef struct {
     uint32_t packet_len;
     /* guest page size */
     uint32_t page_size;
+    /* number of pages in a full packet */
+    uint32_t page_count;
 
     /* syncs main thread and channels */
     QemuSemaphore sem_sync;