sheepdog: cleanup repeated expression

The expression "SD_INODE_SIZE - sizeof(inode.data_vdi_id)" already has a macro
defined for the same value (though with a nicer definition using offsetof).
Replace it.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20180523160721.14018-2-pbonzini@redhat.com>
Signed-off-by: Jeff Cody <jcody@redhat.com>

diff --git a/block/sheepdog.c b/block/sheepdog.c
index 2a5bc0a59a571fef325d2d89f9dcb1d2be318d91..cfc0e28aa564fa158017da7d9ace6c819d8096ad 100644 (file)
--- a/block/sheepdog.c
+++ b/block/sheepdog.c
@@ -2335,7 +2335,7 @@ static int sd_truncate(BlockDriverState *bs, int64_t offset,
     }
 
     /* we don't need to update entire object */
-    datalen = SD_INODE_SIZE - sizeof(s->inode.data_vdi_id);
+    datalen = SD_INODE_HEADER_SIZE;
     s->inode.vdi_size = offset;
     ret = write_object(fd, s->bs, (char *)&s->inode,
                        vid_to_vdi_oid(s->inode.vdi_id), s->inode.nr_copies,
@@ -2703,7 +2703,7 @@ static int sd_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
      */
     strncpy(s->inode.tag, sn_info->name, sizeof(s->inode.tag));
     /* we don't need to update entire object */
-    datalen = SD_INODE_SIZE - sizeof(s->inode.data_vdi_id);
+    datalen = SD_INODE_HEADER_SIZE;
     inode = g_malloc(datalen);
 
     /* refresh inode. */
@@ -2989,7 +2989,7 @@ static int sd_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
         /* we don't need to read entire object */
         ret = read_object(fd, s->bs, (char *)&inode,
                           vid_to_vdi_oid(vid),
-                          0, SD_INODE_SIZE - sizeof(inode.data_vdi_id), 0,
+                          0, SD_INODE_HEADER_SIZE, 0,
                           s->cache_flags);
 
         if (ret) {