This patch add function bdrv_query_snapshot_infolist(), which will
return snapshot info of an image in qmp object format. The implementation
code are based on the code moved from qemu-img.c with modification to fit more
for qmp based block layer API.
To help filter out snapshot info not needed, a call back function is
added in bdrv_query_snapshot_infolist().
bdrv_can_read_snapshot() should be called before call this function,
to avoid got *errp set unexpectedly.
Signed-off-by: Wenchao Xia <xiaw...@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
---
block.c | 60 ++++++++++++++++++++++++++++++++++++++----------
include/block/block.h | 8 +++++-
qemu-img.c | 8 +++++-
3 files changed, 61 insertions(+), 15 deletions(-)
diff --git a/block.c b/block.c
index 368b37c..8d0145a 100644
--- a/block.c
+++ b/block.c
@@ -2813,29 +2813,62 @@ int coroutine_fn
bdrv_co_is_allocated_above(BlockDriverState *top,
return 0;
}
-void collect_snapshots(BlockDriverState *bs , ImageInfo *info)
+SnapshotInfoList *bdrv_query_snapshot_infolist(BlockDriverState *bs,
+ SnapshotFilterFunc filter,
+ void *opaque,
+ Error **errp)
{
int i, sn_count;
QEMUSnapshotInfo *sn_tab = NULL;
- SnapshotInfoList *info_list, *cur_item = NULL;
+ SnapshotInfoList *info_list, *cur_item = NULL, *head = NULL;
+ SnapshotInfo *info;
+
sn_count = bdrv_snapshot_list(bs, &sn_tab);
+ if (sn_count < 0) {
+ /* Now bdrv_snapshot_list() use negative value to tip error, so a check
+ * of it was done here. In future errp can be set by that function
+ * itself, by changing the call back functions in c files in ./block.
+ */
+ const char *dev = bdrv_get_device_name(bs);
+ switch (sn_count) {
+ case -ENOMEDIUM:
+ error_setg(errp, "Device '%s' is not inserted.", dev);
+ break;
+ case -ENOTSUP:
+ error_setg(errp,
+ "Device '%s' does not support internal snapshot.",
+ dev);
+ break;
+ default:
+ error_setg(errp,
+ "Device '%s' got '%d' for bdrv_snapshot_list(), "
+ "message '%s'.",
+ dev, sn_count, strerror(-sn_count));
+ break;
+ }
+ return NULL;
+ }
for (i = 0; i < sn_count; i++) {
- info->has_snapshots = true;
- info_list = g_new0(SnapshotInfoList, 1);
+ if (filter && filter(&sn_tab[i], opaque) != 0) {
+ continue;
+ }
- info_list->value = g_new0(SnapshotInfo, 1);
- info_list->value->id = g_strdup(sn_tab[i].id_str);
- info_list->value->name = g_strdup(sn_tab[i].name);
- info_list->value->vm_state_size = sn_tab[i].vm_state_size;
- info_list->value->date_sec = sn_tab[i].date_sec;
- info_list->value->date_nsec = sn_tab[i].date_nsec;
- info_list->value->vm_clock_sec = sn_tab[i].vm_clock_nsec / 1000000000;
- info_list->value->vm_clock_nsec = sn_tab[i].vm_clock_nsec % 1000000000;
+ info = g_new0(SnapshotInfo, 1);
+ info->id = g_strdup(sn_tab[i].id_str);
+ info->name = g_strdup(sn_tab[i].name);
+ info->vm_state_size = sn_tab[i].vm_state_size;
+ info->date_sec = sn_tab[i].date_sec;
+ info->date_nsec = sn_tab[i].date_nsec;
+ info->vm_clock_sec = sn_tab[i].vm_clock_nsec / 1000000000;
+ info->vm_clock_nsec = sn_tab[i].vm_clock_nsec % 1000000000;
+
+ info_list = g_new0(SnapshotInfoList, 1);
+ info_list->value = info;
/* XXX: waiting for the qapi to support qemu-queue.h types */
if (!cur_item) {
- info->snapshots = cur_item = info_list;
+ head = cur_item = info_list;
} else {
cur_item->next = info_list;
cur_item = info_list;
@@ -2844,6 +2877,7 @@ void collect_snapshots(BlockDriverState *bs , ImageInfo
*info)
}
g_free(sn_tab);
+ return head;
}
void collect_image_info(BlockDriverState *bs,
diff --git a/include/block/block.h b/include/block/block.h
index e6d915c..51a14f2 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -319,6 +319,13 @@ void bdrv_get_backing_filename(BlockDriverState *bs,
char *filename, int filename_size);
void bdrv_get_full_backing_filename(BlockDriverState *bs,
char *dest, size_t sz);
+
+typedef int (*SnapshotFilterFunc)(const QEMUSnapshotInfo *sn, void *opaque);
+/* assume bs is already opened, use qapi_free_* to free returned value. */
+SnapshotInfoList *bdrv_query_snapshot_infolist(BlockDriverState *bs,
+ SnapshotFilterFunc filter,
+ void *opaque,
+ Error **errp);
BlockInfo *bdrv_query_info(BlockDriverState *s);
BlockStats *bdrv_query_stats(const BlockDriverState *bs);
bool bdrv_can_read_snapshot(BlockDriverState *bs);
@@ -450,7 +457,6 @@ int bdrv_debug_breakpoint(BlockDriverState *bs, const char
*event,
int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
-void collect_snapshots(BlockDriverState *bs , ImageInfo *info);
void collect_image_info(BlockDriverState *bs,
ImageInfo *info,
const char *filename);
diff --git a/qemu-img.c b/qemu-img.c
index b650d17..1034cc5 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1280,7 +1280,13 @@ static ImageInfoList *collect_image_info_list(const char
*filename,
info = g_new0(ImageInfo, 1);
collect_image_info(bs, info, filename);
- collect_snapshots(bs, info);
+ if (bdrv_can_read_snapshot(bs)) {
+ info->snapshots = bdrv_query_snapshot_infolist(bs, NULL,
+ NULL, NULL);
+ if (info->snapshots) {
+ info->has_snapshots = true;
+ }
+ }
elem = g_new0(ImageInfoList, 1);
elem->value = info;
--
1.7.1
