22.10.2020 21:13, Andrey Shinkevich wrote:
Avoid writing a filter JSON file name and a filter format name to QCOW2
image when the backing file is changed after the block stream job.
A user is still able to assign the 'backing-file' parameter for a
block-stream job keeping in mind the possible issue mentioned above.
If the user does not specify the 'backing-file' parameter, QEMU will
assign it automatically.
Signed-off-by: Andrey Shinkevich <andrey.shinkev...@virtuozzo.com>
---
block/stream.c | 15 +++++++++++++--
blockdev.c | 9 ++-------
2 files changed, 15 insertions(+), 9 deletions(-)
diff --git a/block/stream.c b/block/stream.c
index e0540ee..1ba74ab 100644
--- a/block/stream.c
+++ b/block/stream.c
@@ -65,6 +65,7 @@ static int stream_prepare(Job *job)
BlockDriverState *bs = blk_bs(bjob->blk);
BlockDriverState *unfiltered_bs = bdrv_skip_filters(bs);
BlockDriverState *base = bdrv_filter_or_cow_bs(s->above_base);
+ BlockDriverState *base_unfiltered = NULL;
Error *local_err = NULL;
int ret = 0;
@@ -75,8 +76,18 @@ static int stream_prepare(Job *job)
const char *base_id = NULL, *base_fmt = NULL;
if (base) {
base_id = s->backing_file_str;
- if (base->drv) {
- base_fmt = base->drv->format_name;
+ if (base_id) {
+ if (base->drv) {
+ base_fmt = base->drv->format_name;
hmm. this doesn't make real sense: so, we assume that user specified
backing_file_str, which may not relate to base, but we use
base->drv->format_name? But it may be name of the filter driver, which would be
wrong..
Any ideas?
1. we can use base_fmt=NULL, to provoke probing on next open of the qcow2 file..
2. we can do probing now
3. we can at least check, if backing_file_str == base_unfiltered->filename, in this
case we can use base_unfiltered->drv->format_name
+ }
+ } else {
+ base_unfiltered = bdrv_skip_filters(base);
+ if (base_unfiltered) {
+ base_id = base_unfiltered->filename;
+ if (base_unfiltered->drv) {
+ base_fmt = base_unfiltered->drv->format_name;
+ }
+ }
}
}
bdrv_set_backing_hd(unfiltered_bs, base, &local_err);
diff --git a/blockdev.c b/blockdev.c
index c917625..0e9c783 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -2508,7 +2508,6 @@ void qmp_block_stream(bool has_job_id, const char
*job_id, const char *device,
BlockDriverState *base_bs = NULL;
AioContext *aio_context;
Error *local_err = NULL;
- const char *base_name = NULL;
int job_flags = JOB_DEFAULT;
if (!has_on_error) {
@@ -2536,7 +2535,6 @@ void qmp_block_stream(bool has_job_id, const char
*job_id, const char *device,
goto out;
}
assert(bdrv_get_aio_context(base_bs) == aio_context);
- base_name = base;
}
if (has_base_node) {
@@ -2551,7 +2549,6 @@ void qmp_block_stream(bool has_job_id, const char
*job_id, const char *device,
}
assert(bdrv_get_aio_context(base_bs) == aio_context);
bdrv_refresh_filename(base_bs);
- base_name = base_bs->filename;
}
/* Check for op blockers in the whole chain between bs and base */
@@ -2571,9 +2568,6 @@ void qmp_block_stream(bool has_job_id, const char
*job_id, const char *device,
goto out;
}
- /* backing_file string overrides base bs filename */
- base_name = has_backing_file ? backing_file : base_name;
-
if (has_auto_finalize && !auto_finalize) {
job_flags |= JOB_MANUAL_FINALIZE;
}
@@ -2581,7 +2575,8 @@ void qmp_block_stream(bool has_job_id, const char
*job_id, const char *device,
job_flags |= JOB_MANUAL_DISMISS;
}
- stream_start(has_job_id ? job_id : NULL, bs, base_bs, base_name,
+ stream_start(has_job_id ? job_id : NULL, bs, base_bs,
+ has_backing_file ? backing_file : NULL,
backing_file should be NULL if has_backing_file is false, so you can use just
backing_file instead of ternary operator.
job_flags, has_speed ? speed : 0, on_error,
filter_node_name, &local_err);
if (local_err) {
--
Best regards,
Vladimir
