On 6/21/23 19:08, Denis V. Lunev wrote:
On 6/7/23 17:26, Andrey Drobyshev wrote:
Functions qcow2_get_host_offset(), get_cluster_offset() explicitly
report compressed cluster types when data is compressed. However, this
information is never passed further. Let's make use of it by adding new
BDRV_BLOCK_COMPRESSED flag for bdrv_block_status(), so that caller may
know that the data range is compressed. In particular, we're going to
use this flag to tweak "qemu-img map" output.
This new flag is only being utilized by qcow and qcow2 formats, as only
these two support compression.
Signed-off-by: Andrey Drobyshev <andrey.drobys...@virtuozzo.com>
---
block/qcow.c | 5 ++++-
block/qcow2.c | 3 +++
include/block/block-common.h | 3 +++
3 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/block/qcow.c b/block/qcow.c
index 3644bbf5cb..8416bcc2c3 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -549,7 +549,10 @@ qcow_co_block_status(BlockDriverState *bs, bool
want_zero,
if (!cluster_offset) {
return 0;
}
- if ((cluster_offset & QCOW_OFLAG_COMPRESSED) || s->crypto) {
+ if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+ return BDRV_BLOCK_DATA | BDRV_BLOCK_COMPRESSED;
+ }
+ if (s->crypto) {
return BDRV_BLOCK_DATA;
}
*map = cluster_offset | index_in_cluster;
diff --git a/block/qcow2.c b/block/qcow2.c
index e23edd48c2..8e01adc610 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2162,6 +2162,9 @@ qcow2_co_block_status(BlockDriverState *bs,
bool want_zero, int64_t offset,
{
status |= BDRV_BLOCK_RECURSE;
}
+ if (type == QCOW2_SUBCLUSTER_COMPRESSED) {
+ status |= BDRV_BLOCK_COMPRESSED;
+ }
return status;
}
diff --git a/include/block/block-common.h
b/include/block/block-common.h
index e15395f2cb..f7a4e7d4db 100644
--- a/include/block/block-common.h
+++ b/include/block/block-common.h
@@ -282,6 +282,8 @@ typedef enum {
* layer rather than any backing, set by
block layer
* BDRV_BLOCK_EOF: the returned pnum covers through end of file for
this
* layer, set by block layer
+ * BDRV_BLOCK_COMPRESSED: the underlying data is compressed; only
valid for
+ * the formats supporting compression: qcow,
qcow2
*
* Internal flags:
* BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to
request
@@ -317,6 +319,7 @@ typedef enum {
#define BDRV_BLOCK_ALLOCATED 0x10
#define BDRV_BLOCK_EOF 0x20
#define BDRV_BLOCK_RECURSE 0x40
+#define BDRV_BLOCK_COMPRESSED 0x80
typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry)
BlockReopenQueue;
Reviewed-by: Denis V. Lunev <d...@openvz.org>
Looking into the second patch I have found that I was a too fast here :)
The comment is misleading and the patch is incomplete.
static inline bool TSA_NO_TSA block_driver_can_compress(BlockDriver *drv)
{
return drv->bdrv_co_pwritev_compressed ||
drv->bdrv_co_pwritev_compressed_part;
}
which means that
1 257 block/copy-on-read.c <<GLOBAL>>
.bdrv_co_pwritev_compressed = cor_co_pwritev_compressed,
2 1199 block/qcow.c <<GLOBAL>>
.bdrv_co_pwritev_compressed = qcow_co_pwritev_compressed,
3 255 block/throttle.c <<GLOBAL>>
.bdrv_co_pwritev_compressed = throttle_co_pwritev_compressed,
4 3108 block/vmdk.c <<GLOBAL>>
.bdrv_co_pwritev_compressed = vmdk_co_pwritev_compressed,
1 6121 block/qcow2.c <<GLOBAL>>
.bdrv_co_pwritev_compressed_part...cow2_co_pwritev_compressed_part,
We have missed at least VMDK images.