Functions qcow2_get_host_offset(), get_cluster_offset(),
vmdk_co_block_status() 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, qcow2 and vmdk formats, as only
those support compression.
Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
---
block/qcow.c | 5 ++++-
block/qcow2.c | 3 +++
block/vmdk.c | 2 ++
include/block/block-common.h | 3 +++
4 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/block/qcow.c b/block/qcow.c
index 577bd70324..d56d24ab6d 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 c51388e99d..77885fe27c 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/block/vmdk.c b/block/vmdk.c
index 70066c2b01..56b3d5151d 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -1770,6 +1770,8 @@ vmdk_co_block_status(BlockDriverState *bs, bool want_zero,
if (extent->flat) {
ret |= BDRV_BLOCK_RECURSE;
}
+ } else {
+ ret |= BDRV_BLOCK_COMPRESSED;
}
*file = extent->file->bs;
break;
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;
--
2.39.3On 06.07.23 18:30, Andrey Drobyshev wrote: > Functions qcow2_get_host_offset(), get_cluster_offset(), > vmdk_co_block_status() 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, qcow2 and vmdk formats, as only > those support compression. > > Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com> > --- > block/qcow.c | 5 ++++- > block/qcow2.c | 3 +++ > block/vmdk.c | 2 ++ > include/block/block-common.h | 3 +++ > 4 files changed, 12 insertions(+), 1 deletion(-) Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
On 7/6/23 18:30, Andrey Drobyshev wrote:
> Functions qcow2_get_host_offset(), get_cluster_offset(),
> vmdk_co_block_status() 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, qcow2 and vmdk formats, as only
> those support compression.
>
> Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
> ---
> block/qcow.c | 5 ++++-
> block/qcow2.c | 3 +++
> block/vmdk.c | 2 ++
> include/block/block-common.h | 3 +++
> 4 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/block/qcow.c b/block/qcow.c
> index 577bd70324..d56d24ab6d 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 c51388e99d..77885fe27c 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/block/vmdk.c b/block/vmdk.c
> index 70066c2b01..56b3d5151d 100644
> --- a/block/vmdk.c
> +++ b/block/vmdk.c
> @@ -1770,6 +1770,8 @@ vmdk_co_block_status(BlockDriverState *bs, bool want_zero,
> if (extent->flat) {
> ret |= BDRV_BLOCK_RECURSE;
> }
> + } else {
> + ret |= BDRV_BLOCK_COMPRESSED;
> }
> *file = extent->file->bs;
> break;
> 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 <den@openvz.org>
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