Re: [Qemu-devel] [PATCH V5 05/13] block: add image info query function bdrv_query_image_info()

[Wenchao Xia]

于 2013-1-29 20:55, Kevin Wolf 写道:

Am 24.01.2013 03:57, schrieb Wenchao Xia:

   This patch add function bdrv_query_image_info(), which will return
image info in qmp object format. The implementation code are mostly
copied from qemu-img.c, but use block layer function to get snapshot
info.

Don't copy code, reuse it.

Can you move the existing qemu-img code to block.c and make qemu-img use
it from there?

  A bit hard, original code are adjusted to form two API:image_info and
snapshot info. Those code can be moved to block.c in one patch and
in following patch modified, if you like.

   A check with bdrv_can_read_snapshot(), was done before collecting
snapshot info.

Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
---
  block.c               |   73 +++++++++++++++++++++++++++++++++++++++++++++++++
  include/block/block.h |    1 +
  2 files changed, 74 insertions(+), 0 deletions(-)

diff --git a/block.c b/block.c
index 7cdb6c6..14bf653 100644
--- a/block.c
+++ b/block.c
@@ -2902,6 +2902,79 @@ SnapshotInfoList 
*bdrv_query_snapshot_infolist(BlockDriverState *bs,
      return head;
  }

+/* collect all internal snapshot info in a image for ImageInfo */
+static void collect_snapshots_info(BlockDriverState *bs,
+                                   ImageInfo *info,
+                                   Error **errp)
+{
+    SnapshotInfoList *info_list;
+
+    if (!bdrv_can_read_snapshot(bs)) {
+        return;
+    }
+    info_list = bdrv_query_snapshot_infolist(bs, NULL, NULL, errp);
+    if (info_list != NULL) {
+        info->has_snapshots = true;
+        info->snapshots = info_list;
+    }
+}
+
+static void collect_image_info(BlockDriverState *bs,
+                               ImageInfo *info)
+{
+    uint64_t total_sectors;
+    char backing_filename[1024];
+    char backing_filename2[1024];
+    BlockDriverInfo bdi;
+    const char *filename;
+
+    filename = bdrv_get_filename(bs);
+    bdrv_get_geometry(bs, &total_sectors);
+
+    info->filename        = g_strdup(filename);
+    info->format          = g_strdup(bdrv_get_format_name(bs));
+    info->virtual_size    = total_sectors * 512;
+    info->actual_size     = bdrv_get_allocated_file_size(bs);
+    info->has_actual_size = info->actual_size >= 0;
+    if (bdrv_is_encrypted(bs)) {
+        info->encrypted = true;
+        info->has_encrypted = true;
+    }
+    if (bdrv_get_info(bs, &bdi) >= 0) {
+        if (bdi.cluster_size != 0) {
+            info->cluster_size = bdi.cluster_size;
+            info->has_cluster_size = true;
+        }
+        info->dirty_flag = bdi.is_dirty;
+        info->has_dirty_flag = true;
+    }
+    bdrv_get_backing_filename(bs, backing_filename, sizeof(backing_filename));

No need to copy this, you can directly access bs->backing_file.

  OK.

Kevin

--
Best Regards

Wenchao Xia