Wenchao Xia <xiaw...@linux.vnet.ibm.com> writes: > This patch adds function bdrv_query_image_info(), which will > retrieve image info in qmp object format. The implementation is > based on the code moved from qemu-img.c, but uses block layer > function to get snapshot info. > > Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com> > --- > block/qapi.c | 41 ++++++++++++++++++++++++++++++++++------- > include/block/qapi.h | 6 +++--- > qemu-img.c | 8 ++------ > 3 files changed, 39 insertions(+), 16 deletions(-) > > diff --git a/block/qapi.c b/block/qapi.c > index 19d4d93..176a479 100644 > --- a/block/qapi.c > +++ b/block/qapi.c > @@ -122,18 +122,22 @@ int bdrv_query_snapshot_info_list(BlockDriverState *bs, > return 0; > } > > -void bdrv_collect_image_info(BlockDriverState *bs, > - ImageInfo *info, > - const char *filename) > +/* return 0 on success, and @p_info will be set only on success. */ > +int bdrv_query_image_info(BlockDriverState *bs, > + ImageInfo **p_info, > + Error **errp) > { > uint64_t total_sectors; > - char backing_filename[1024]; > + const char *backing_filename; > char backing_filename2[1024]; > BlockDriverInfo bdi; > + int ret; > + Error *err = NULL; > + ImageInfo *info = g_new0(ImageInfo, 1); > > bdrv_get_geometry(bs, &total_sectors); > > - info->filename = g_strdup(filename); > + info->filename = g_strdup(bs->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); > @@ -150,8 +154,8 @@ void bdrv_collect_image_info(BlockDriverState *bs, > info->dirty_flag = bdi.is_dirty; > info->has_dirty_flag = true; > } > - bdrv_get_backing_filename(bs, backing_filename, > sizeof(backing_filename)); > - if (backing_filename[0] != '\0') { > + backing_filename = bs->backing_file; > + if (backing_filename && backing_filename[0] != '\0') {
backing_filename can't possibly be null here, because bs->backing_file is an array. > info->backing_filename = g_strdup(backing_filename); > info->has_backing_filename = true; > bdrv_get_full_backing_filename(bs, backing_filename2, > @@ -168,4 +172,27 @@ void bdrv_collect_image_info(BlockDriverState *bs, > info->has_backing_filename_format = true; > } > } > + > + ret = bdrv_query_snapshot_info_list(bs, &info->snapshots, false, &err); > + switch (ret) { > + case 0: > + if (info->snapshots) { > + info->has_snapshots = true; > + } > + break; > + /* recoverable error */ > + case -ENOMEDIUM: > + error_free(err); > + break; > + case -ENOTSUP: > + error_free(err); > + break; Suggest case -ENOMEDIUM: case -ENOTSUP: /* no snapshots on this device */ error_free(err); break; for clarity. > + default: > + error_propagate(errp, err); > + qapi_free_ImageInfo(info); > + return ret; > + } > + > + *p_info = info; > + return 0; > } > diff --git a/include/block/qapi.h b/include/block/qapi.h > index fe66053..2c62fdf 100644 > --- a/include/block/qapi.h > +++ b/include/block/qapi.h > @@ -32,7 +32,7 @@ int bdrv_query_snapshot_info_list(BlockDriverState *bs, > SnapshotInfoList **p_list, > bool vm_snapshot, > Error **errp); > -void bdrv_collect_image_info(BlockDriverState *bs, > - ImageInfo *info, > - const char *filename); > +int bdrv_query_image_info(BlockDriverState *bs, > + ImageInfo **p_info, > + Error **errp); > #endif > diff --git a/qemu-img.c b/qemu-img.c > index 261c277..1dd0a60 100644 > --- a/qemu-img.c > +++ b/qemu-img.c > @@ -1733,12 +1733,8 @@ static ImageInfoList *collect_image_info_list(const > char *filename, > goto err; > } > > - info = g_new0(ImageInfo, 1); > - bdrv_collect_image_info(bs, info, filename); > - if (!bdrv_query_snapshot_info_list(bs, &info->snapshots, > - false, NULL) && > - info->snapshots) { > - info->has_snapshots = true; > + if (bdrv_query_image_info(bs, &info, NULL)) { > + goto err; > } > > elem = g_new0(ImageInfoList, 1);