migration/rdma: Simplify the function that saves a page

When we sent a page through QEMUFile hooks (RDMA) there are three
posiblities:
- We are not using RDMA. return RAM_SAVE_CONTROL_DELAYED and
  control_save_page() returns false to let anything else to proceed.
- There is one error but we are using RDMA.  Then we return a negative
  value, control_save_page() needs to return true.
- Everything goes well and RDMA start the sent of the page
  asynchronously.  It returns RAM_SAVE_CONTROL_DELAYED and we need to
  return 1 for ram_save_page_legacy.

Clear?

I know, I know, the interface is as bad as it gets.  I think that now
it is a bit clearer, but this needs to be done some other way.

Reviewed-by: Leonardo Bras <leobras@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230515195709.63843-16-quintela@redhat.com>

1 files changed, 6 insertions, 6 deletions

diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 5c43fa34e7..5e8207dae4 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -322,14 +322,14 @@ void ram_control_load_hook(QEMUFile *f, uint64_t flags, void *data)
     }
 }
 
-size_t ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
-                             ram_addr_t offset, size_t size,
-                             uint64_t *bytes_sent)
+int ram_control_save_page(QEMUFile *f, ram_addr_t block_offset,
+                          ram_addr_t offset, size_t size)
 {
     if (f->hooks && f->hooks->save_page) {
-        int ret = f->hooks->save_page(f, block_offset,
-                                      offset, size, bytes_sent);
-
+        int ret = f->hooks->save_page(f, block_offset, offset, size);
+        /*
+         * RAM_SAVE_CONTROL_* are negative values
+         */
         if (ret != RAM_SAVE_CONTROL_DELAYED &&
             ret != RAM_SAVE_CONTROL_NOT_SUPP) {
             if (ret < 0) {