1 files changed, 19 insertions, 14 deletions

diff --git a/arch_init.c b/arch_init.c
index 150647b6bb..7545d96739 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -150,10 +150,9 @@ int qemu_read_default_config_files(bool userconfig)
     return 0;
 }
 
-static inline bool is_zero_page(uint8_t *p)
+static inline bool is_zero_range(uint8_t *p, uint64_t size)
 {
-    return buffer_find_nonzero_offset(p, TARGET_PAGE_SIZE) ==
-        TARGET_PAGE_SIZE;
+    return buffer_find_nonzero_offset(p, size) == size;
 }
 
 /* struct contains XBZRLE cache and a static page
@@ -497,7 +496,7 @@ static int ram_save_block(QEMUFile *f, bool last_stage)
                         acct_info.dup_pages++;
                     }
                 }
-            } else if (is_zero_page(p)) {
+            } else if (is_zero_range(p, TARGET_PAGE_SIZE)) {
                 acct_info.dup_pages++;
                 bytes_sent = save_block_hdr(f, block, offset, cont,
                                             RAM_SAVE_FLAG_COMPRESS);
@@ -710,15 +709,20 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)
      */
     ram_control_after_iterate(f, RAM_CONTROL_ROUND);
 
+    bytes_transferred += total_sent;
+
+    /*
+     * Do not count these 8 bytes into total_sent, so that we can
+     * return 0 if no page had been dirtied.
+     */
+    qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
+    bytes_transferred += 8;
+
+    ret = qemu_file_get_error(f);
     if (ret < 0) {
-        bytes_transferred += total_sent;
         return ret;
     }
 
-    qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
-    total_sent += 8;
-    bytes_transferred += total_sent;
-
     return total_sent;
 }
 
@@ -844,13 +848,14 @@ static inline void *host_from_stream_offset(QEMUFile *f,
  */
 void ram_handle_compressed(void *host, uint8_t ch, uint64_t size)
 {
-    if (ch != 0 || !is_zero_page(host)) {
+    if (ch != 0 || !is_zero_range(host, size)) {
         memset(host, ch, size);
 #ifndef _WIN32
-        if (ch == 0 &&
-            (!kvm_enabled() || kvm_has_sync_mmu()) &&
-            getpagesize() <= TARGET_PAGE_SIZE) {
-            qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED);
+        if (ch == 0 && (!kvm_enabled() || kvm_has_sync_mmu())) {
+            size = size & ~(getpagesize() - 1);
+            if (size > 0) {
+                qemu_madvise(host, size, QEMU_MADV_DONTNEED);
+            }
         }
 #endif
     }