Add description for VIR_MIGRATE_PARAM_COMPRESSION, it will
be reused in choosing compression method during parallel migration.
Add public API VIR_MIGRATE_PARAM_COMPRESSION_ZLIB_LEVEL,
VIR_MIGRATE_PARAM_COMPRESSION_ZSTD_LEVEL for migration APIs
to support set compress level during parallel migration.

Signed-off-by: Jiang Jiacheng <jiangjiacheng@huawei.com>
---
 include/libvirt/libvirt-domain.h | 30 +++++++++++++++++++++++++++---
 1 file changed, 27 insertions(+), 3 deletions(-)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 5152ed4551..40b6b19495 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -1269,9 +1269,11 @@ typedef enum {
  * VIR_MIGRATE_PARAM_COMPRESSION:
  *
  * virDomainMigrate* params multiple field: name of the method used to
- * compress migration traffic. Supported compression methods: xbzrle, mt.
- * The parameter may be specified multiple times if more than one method
- * should be used.
+ * compress migration traffic. Supported compression methods: xbzrle, mt,
+ * zlib, zstd. The parameter may be specified multiple times if more than
+ * one method. Not all combinations of compression methods and migration
+ * options may be allowed. Parallel migration of QEMU domains is only
+ * compatible with either zlib or zstd method.
  *
  * Since: 1.3.4
  */
@@ -1318,6 +1320,28 @@ typedef enum {
  */
 # define VIR_MIGRATE_PARAM_COMPRESSION_XBZRLE_CACHE "compression.xbzrle.cache"
 
+/**
+ * VIR_MIGRATE_PARAM_COMPRESSION_ZLIB_LEVEL:
+ *
+ * virDomainMigrate* params field: the level of compression for zlib as
+ * VIR_TYPED_PARAM_INT. Accepted values are in range 0-9. 0 is no compression,
+ * 1 is maximum speed and 9 is maximum compression.
+ *
+ * Since: 9.1.0
+ */
+# define VIR_MIGRATE_PARAM_COMPRESSION_ZLIB_LEVEL      "compression.zlib.level"
+
+/**
+ * VIR_MIGRATE_PARAM_COMPRESSION_ZSTD_LEVEL:
+ *
+ * virDomainMigrate* params field: the level of compression for zstd as
+ * VIR_TYPED_PARAM_INT. Accepted values are in range 0-20. 0 is no compression,
+ * 1 is maximum speed and 20 is maximum compression.
+ *
+ * Since: 9.1.0
+ */
+# define VIR_MIGRATE_PARAM_COMPRESSION_ZSTD_LEVEL      "compression.zstd.level"
+
 /**
  * VIR_MIGRATE_PARAM_AUTO_CONVERGE_INITIAL:
  *
-- 
2.33.0

On Fri, Feb 24, 2023 at 17:27:10 +0800, Jiang Jiacheng wrote:
> Add description for VIR_MIGRATE_PARAM_COMPRESSION, it will
> be reused in choosing compression method during parallel migration.
> Add public API VIR_MIGRATE_PARAM_COMPRESSION_ZLIB_LEVEL,
> VIR_MIGRATE_PARAM_COMPRESSION_ZSTD_LEVEL for migration APIs
> to support set compress level during parallel migration.
> 
> Signed-off-by: Jiang Jiacheng <jiangjiacheng@huawei.com>
> ---
>  include/libvirt/libvirt-domain.h | 30 +++++++++++++++++++++++++++---
>  1 file changed, 27 insertions(+), 3 deletions(-)
> 
> diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
> index 5152ed4551..40b6b19495 100644
> --- a/include/libvirt/libvirt-domain.h
> +++ b/include/libvirt/libvirt-domain.h
> @@ -1269,9 +1269,11 @@ typedef enum {
>   * VIR_MIGRATE_PARAM_COMPRESSION:
>   *
>   * virDomainMigrate* params multiple field: name of the method used to
> - * compress migration traffic. Supported compression methods: xbzrle, mt.
> - * The parameter may be specified multiple times if more than one method
> - * should be used.
> + * compress migration traffic. Supported compression methods: xbzrle, mt,
> + * zlib, zstd. The parameter may be specified multiple times if more than
> + * one method. Not all combinations of compression methods and migration

Looks like something is missing after "if more than one method" here.
Perhaps "if more than one method should be used"?

> + * options may be allowed. Parallel migration of QEMU domains is only
> + * compatible with either zlib or zstd method.
>   *
>   * Since: 1.3.4
>   */
...

With the following suggested changes
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 46b10fd908..984ae8883b 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -1272,9 +1272,9 @@ typedef enum {
  * virDomainMigrate* params multiple field: name of the method used to
  * compress migration traffic. Supported compression methods: xbzrle, mt,
  * zlib, zstd. The parameter may be specified multiple times if more than
- * one method. Not all combinations of compression methods and migration
- * options may be allowed. Parallel migration of QEMU domains is only
- * compatible with either zlib or zstd method.
+ * one method should be used. Not all combinations of compression methods
+ * and migration options may be allowed. Parallel migration of QEMU domains
+ * is only compatible with either zlib or zstd method.
  *
  * Since: 1.3.4
  */