[Qemu-devel] [PATCH v8 15/20] migration: Send the fd number which we are going to use for this page

[Juan Quintela <quintela@redhat.com>]

We are still sending the page through the main channel, that would
change later in the series

Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
---
 migration/ram.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index 179b45eea7..3f60f7e40c 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -597,7 +597,7 @@ static uint16_t multifd_send_page(uint8_t *address, bool last_page)
     qemu_mutex_unlock(&p->mutex);
     qemu_sem_post(&p->sem);
 
-    return 0;
+    return i;
 }
 
 struct MultiFDRecvParams {
@@ -1186,6 +1186,7 @@ static int ram_multifd_page(RAMState *rs, PageSearchStatus *pss,
                             bool last_stage)
 {
     int pages;
+    uint16_t fd_num;
     uint8_t *p;
     RAMBlock *block = pss->block;
     ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
@@ -1197,8 +1198,10 @@ static int ram_multifd_page(RAMState *rs, PageSearchStatus *pss,
         ram_counters.transferred +=
             save_page_header(rs, rs->f, block,
                              offset | RAM_SAVE_FLAG_MULTIFD_PAGE);
+        fd_num = multifd_send_page(p, rs->migration_dirty_pages == 1);
+        qemu_put_be16(rs->f, fd_num);
+        ram_counters.transferred += 2; /* size of fd_num */
         qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
-        multifd_send_page(p, rs->migration_dirty_pages == 1);
         ram_counters.transferred += TARGET_PAGE_SIZE;
         pages = 1;
         ram_counters.normal++;
@@ -2948,6 +2951,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
     while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
         ram_addr_t addr, total_ram_bytes;
         void *host = NULL;
+        uint16_t fd_num;
         uint8_t ch;
 
         addr = qemu_get_be64(f);
@@ -3058,6 +3062,11 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
             break;
 
         case RAM_SAVE_FLAG_MULTIFD_PAGE:
+            fd_num = qemu_get_be16(f);
+            if (fd_num != 0) {
+                /* this is yet an unused variable, changed later */
+                fd_num = fd_num;
+            }
             qemu_get_buffer(f, host, TARGET_PAGE_SIZE);
             break;
 
-- 
2.13.5