Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2020-05-13' into staging

Block patches:
- zstd compression for qcow2
- Fix use-after-free

# gpg: Signature made Wed 13 May 2020 15:14:06 BST
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2020-05-13:
  block/block-copy: fix use-after-free of task pointer
  iotests: 287: add qcow2 compression type test
  qcow2: add zstd cluster compression
  qcow2: rework the cluster compression routine
  qcow2: introduce compression type feature

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

30 files changed, 825 insertions, 163 deletions

diff --git a/block/block-copy.c b/block/block-copy.c
index 03500680f7..4713c8f2a3 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -591,13 +591,13 @@ static int coroutine_fn block_copy_dirty_clusters(BlockCopyState *s,
         }
         if (s->skip_unallocated && !(ret & BDRV_BLOCK_ALLOCATED)) {
             block_copy_task_end(task, 0);
-            g_free(task);
             progress_set_remaining(s->progress,
                                    bdrv_get_dirty_count(s->copy_bitmap) +
                                    s->in_flight_bytes);
             trace_block_copy_skip_range(s, task->offset, task->bytes);
             offset = task_end(task);
             bytes = end - offset;
+            g_free(task);
             continue;
         }
         task->zeroes = ret & BDRV_BLOCK_ZERO;
diff --git a/block/qcow2-threads.c b/block/qcow2-threads.c
index a68126f291..1914baf456 100644
--- a/block/qcow2-threads.c
+++ b/block/qcow2-threads.c
@@ -28,6 +28,11 @@
 #define ZLIB_CONST
 #include <zlib.h>
 
+#ifdef CONFIG_ZSTD
+#include <zstd.h>
+#include <zstd_errors.h>
+#endif
+
 #include "qcow2.h"
 #include "block/thread-pool.h"
 #include "crypto.h"
@@ -74,7 +79,9 @@ typedef struct Qcow2CompressData {
 } Qcow2CompressData;
 
 /*
- * qcow2_compress()
+ * qcow2_zlib_compress()
+ *
+ * Compress @src_size bytes of data using zlib compression method
  *
  * @dest - destination buffer, @dest_size bytes
  * @src - source buffer, @src_size bytes
@@ -83,8 +90,8 @@ typedef struct Qcow2CompressData {
  *          -ENOMEM destination buffer is not enough to store compressed data
  *          -EIO    on any other error
  */
-static ssize_t qcow2_compress(void *dest, size_t dest_size,
-                              const void *src, size_t src_size)
+static ssize_t qcow2_zlib_compress(void *dest, size_t dest_size,
+                                   const void *src, size_t src_size)
 {
     ssize_t ret;
     z_stream strm;
@@ -119,10 +126,10 @@ static ssize_t qcow2_compress(void *dest, size_t dest_size,
 }
 
 /*
- * qcow2_decompress()
+ * qcow2_zlib_decompress()
  *
  * Decompress some data (not more than @src_size bytes) to produce exactly
- * @dest_size bytes.
+ * @dest_size bytes using zlib compression method
  *
  * @dest - destination buffer, @dest_size bytes
  * @src - source buffer, @src_size bytes
@@ -130,8 +137,8 @@ static ssize_t qcow2_compress(void *dest, size_t dest_size,
  * Returns: 0 on success
  *          -EIO on fail
  */
-static ssize_t qcow2_decompress(void *dest, size_t dest_size,
-                                const void *src, size_t src_size)
+static ssize_t qcow2_zlib_decompress(void *dest, size_t dest_size,
+                                     const void *src, size_t src_size)
 {
     int ret;
     z_stream strm;
@@ -164,6 +171,160 @@ static ssize_t qcow2_decompress(void *dest, size_t dest_size,
     return ret;
 }
 
+#ifdef CONFIG_ZSTD
+
+/*
+ * qcow2_zstd_compress()
+ *
+ * Compress @src_size bytes of data using zstd compression method
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: compressed size on success
+ *          -ENOMEM destination buffer is not enough to store compressed data
+ *          -EIO    on any other error
+ */
+static ssize_t qcow2_zstd_compress(void *dest, size_t dest_size,
+                                   const void *src, size_t src_size)
+{
+    ssize_t ret;
+    size_t zstd_ret;
+    ZSTD_outBuffer output = {
+        .dst = dest,
+        .size = dest_size,
+        .pos = 0
+    };
+    ZSTD_inBuffer input = {
+        .src = src,
+        .size = src_size,
+        .pos = 0
+    };
+    ZSTD_CCtx *cctx = ZSTD_createCCtx();
+
+    if (!cctx) {
+        return -EIO;
+    }
+    /*
+     * Use the zstd streamed interface for symmetry with decompression,
+     * where streaming is essential since we don't record the exact
+     * compressed size.
+     *
+     * ZSTD_compressStream2() tries to compress everything it could
+     * with a single call. Although, ZSTD docs says that:
+     * "You must continue calling ZSTD_compressStream2() with ZSTD_e_end
+     * until it returns 0, at which point you are free to start a new frame",
+     * in out tests we saw the only case when it returned with >0 -
+     * when the output buffer was too small. In that case,
+     * ZSTD_compressStream2() expects a bigger buffer on the next call.
+     * We can't provide a bigger buffer because we are limited with dest_size
+     * which we pass to the ZSTD_compressStream2() at once.
+     * So, we don't need any loops and just abort the compression when we
+     * don't get 0 result on the first call.
+     */
+    zstd_ret = ZSTD_compressStream2(cctx, &output, &input, ZSTD_e_end);
+
+    if (zstd_ret) {
+        if (zstd_ret > output.size - output.pos) {
+            ret = -ENOMEM;
+        } else {
+            ret = -EIO;
+        }
+        goto out;
+    }
+
+    /* make sure that zstd didn't overflow the dest buffer */
+    assert(output.pos <= dest_size);
+    ret = output.pos;
+out:
+    ZSTD_freeCCtx(cctx);
+    return ret;
+}
+
+/*
+ * qcow2_zstd_decompress()
+ *
+ * Decompress some data (not more than @src_size bytes) to produce exactly
+ * @dest_size bytes using zstd compression method
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: 0 on success
+ *          -EIO on any error
+ */
+static ssize_t qcow2_zstd_decompress(void *dest, size_t dest_size,
+                                     const void *src, size_t src_size)
+{
+    size_t zstd_ret = 0;
+    ssize_t ret = 0;
+    ZSTD_outBuffer output = {
+        .dst = dest,
+        .size = dest_size,
+        .pos = 0
+    };
+    ZSTD_inBuffer input = {
+        .src = src,
+        .size = src_size,
+        .pos = 0
+    };
+    ZSTD_DCtx *dctx = ZSTD_createDCtx();
+
+    if (!dctx) {
+        return -EIO;
+    }
+
+    /*
+     * The compressed stream from the input buffer may consist of more
+     * than one zstd frame. So we iterate until we get a fully
+     * uncompressed cluster.
+     * From zstd docs related to ZSTD_decompressStream:
+     * "return : 0 when a frame is completely decoded and fully flushed"
+     * We suppose that this means: each time ZSTD_decompressStream reads
+     * only ONE full frame and returns 0 if and only if that frame
+     * is completely decoded and flushed. Only after returning 0,
+     * ZSTD_decompressStream reads another ONE full frame.
+     */
+    while (output.pos < output.size) {
+        size_t last_in_pos = input.pos;
+        size_t last_out_pos = output.pos;
+        zstd_ret = ZSTD_decompressStream(dctx, &output, &input);
+
+        if (ZSTD_isError(zstd_ret)) {
+            ret = -EIO;
+            break;
+        }
+
+        /*
+         * The ZSTD manual is vague about what to do if it reads
+         * the buffer partially, and we don't want to get stuck
+         * in an infinite loop where ZSTD_decompressStream
+         * returns > 0 waiting for another input chunk. So, we add
+         * a check which ensures that the loop makes some progress
+         * on each step.
+         */
+        if (last_in_pos >= input.pos &&
+            last_out_pos >= output.pos) {
+            ret = -EIO;
+            break;
+        }
+    }
+    /*
+     * Make sure that we have the frame fully flushed here
+     * if not, we somehow managed to get uncompressed cluster
+     * greater then the cluster size, possibly because of its
+     * damage.
+     */
+    if (zstd_ret > 0) {
+        ret = -EIO;
+    }
+
+    ZSTD_freeDCtx(dctx);
+    assert(ret == 0 || ret == -EIO);
+    return ret;
+}
+#endif
+
 static int qcow2_compress_pool_func(void *opaque)
 {
     Qcow2CompressData *data = opaque;
@@ -191,20 +352,77 @@ qcow2_co_do_compress(BlockDriverState *bs, void *dest, size_t dest_size,
     return arg.ret;
 }
 
+/*
+ * qcow2_co_compress()
+ *
+ * Compress @src_size bytes of data using the compression
+ * method defined by the image compression type
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: compressed size on success
+ *          a negative error code on failure
+ */
 ssize_t coroutine_fn
 qcow2_co_compress(BlockDriverState *bs, void *dest, size_t dest_size,
                   const void *src, size_t src_size)
 {
-    return qcow2_co_do_compress(bs, dest, dest_size, src, src_size,
-                                qcow2_compress);
+    BDRVQcow2State *s = bs->opaque;
+    Qcow2CompressFunc fn;
+
+    switch (s->compression_type) {
+    case QCOW2_COMPRESSION_TYPE_ZLIB:
+        fn = qcow2_zlib_compress;
+        break;
+
+#ifdef CONFIG_ZSTD
+    case QCOW2_COMPRESSION_TYPE_ZSTD:
+        fn = qcow2_zstd_compress;
+        break;
+#endif
+    default:
+        abort();
+    }
+
+    return qcow2_co_do_compress(bs, dest, dest_size, src, src_size, fn);
 }
 
+/*
+ * qcow2_co_decompress()
+ *
+ * Decompress some data (not more than @src_size bytes) to produce exactly
+ * @dest_size bytes using the compression method defined by the image
+ * compression type
+ *
+ * @dest - destination buffer, @dest_size bytes
+ * @src - source buffer, @src_size bytes
+ *
+ * Returns: 0 on success
+ *          a negative error code on failure
+ */
 ssize_t coroutine_fn
 qcow2_co_decompress(BlockDriverState *bs, void *dest, size_t dest_size,
                     const void *src, size_t src_size)
 {
-    return qcow2_co_do_compress(bs, dest, dest_size, src, src_size,
-                                qcow2_decompress);
+    BDRVQcow2State *s = bs->opaque;
+    Qcow2CompressFunc fn;
+
+    switch (s->compression_type) {
+    case QCOW2_COMPRESSION_TYPE_ZLIB:
+        fn = qcow2_zlib_decompress;
+        break;
+
+#ifdef CONFIG_ZSTD
+    case QCOW2_COMPRESSION_TYPE_ZSTD:
+        fn = qcow2_zstd_decompress;
+        break;
+#endif
+    default:
+        abort();
+    }
+
+    return qcow2_co_do_compress(bs, dest, dest_size, src, src_size, fn);
 }
 
 
diff --git a/block/qcow2.c b/block/qcow2.c
index 1ad95ff048..ad9ab4fafa 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -1242,6 +1242,42 @@ static int qcow2_update_options(BlockDriverState *bs, QDict *options,
     return ret;
 }
 
+static int validate_compression_type(BDRVQcow2State *s, Error **errp)
+{
+    switch (s->compression_type) {
+    case QCOW2_COMPRESSION_TYPE_ZLIB:
+#ifdef CONFIG_ZSTD
+    case QCOW2_COMPRESSION_TYPE_ZSTD:
+#endif
+        break;
+
+    default:
+        error_setg(errp, "qcow2: unknown compression type: %u",
+                   s->compression_type);
+        return -ENOTSUP;
+    }
+
+    /*
+     * if the compression type differs from QCOW2_COMPRESSION_TYPE_ZLIB
+     * the incompatible feature flag must be set
+     */
+    if (s->compression_type == QCOW2_COMPRESSION_TYPE_ZLIB) {
+        if (s->incompatible_features & QCOW2_INCOMPAT_COMPRESSION) {
+            error_setg(errp, "qcow2: Compression type incompatible feature "
+                             "bit must not be set");
+            return -EINVAL;
+        }
+    } else {
+        if (!(s->incompatible_features & QCOW2_INCOMPAT_COMPRESSION)) {
+            error_setg(errp, "qcow2: Compression type incompatible feature "
+                             "bit must be set");
+            return -EINVAL;
+        }
+    }
+
+    return 0;
+}
+
 /* Called with s->lock held.  */
 static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
                                       int flags, Error **errp)
@@ -1357,6 +1393,23 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options,
     s->compatible_features      = header.compatible_features;
     s->autoclear_features       = header.autoclear_features;
 
+    /*
+     * Handle compression type
+     * Older qcow2 images don't contain the compression type header.
+     * Distinguish them by the header length and use
+     * the only valid (default) compression type in that case
+     */
+    if (header.header_length > offsetof(QCowHeader, compression_type)) {
+        s->compression_type = header.compression_type;
+    } else {
+        s->compression_type = QCOW2_COMPRESSION_TYPE_ZLIB;
+    }
+
+    ret = validate_compression_type(s, errp);
+    if (ret) {
+        goto fail;
+    }
+
     if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) {
         void *feature_table = NULL;
         qcow2_read_extensions(bs, header.header_length, ext_end,
@@ -2728,6 +2781,11 @@ int qcow2_update_header(BlockDriverState *bs)
     total_size = bs->total_sectors * BDRV_SECTOR_SIZE;
     refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
 
+    ret = validate_compression_type(s, NULL);
+    if (ret) {
+        goto fail;
+    }
+
     *header = (QCowHeader) {
         /* Version 2 fields */
         .magic                  = cpu_to_be32(QCOW_MAGIC),
@@ -2750,6 +2808,7 @@ int qcow2_update_header(BlockDriverState *bs)
         .autoclear_features     = cpu_to_be64(s->autoclear_features),
         .refcount_order         = cpu_to_be32(s->refcount_order),
         .header_length          = cpu_to_be32(header_length),
+        .compression_type       = s->compression_type,
     };
 
     /* For older versions, write a shorter header */
@@ -2850,6 +2909,11 @@ int qcow2_update_header(BlockDriverState *bs)
                 .name = "external data file",
             },
             {
+                .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
+                .bit  = QCOW2_INCOMPAT_COMPRESSION_BITNR,
+                .name = "compression type",
+            },
+            {
                 .type = QCOW2_FEAT_TYPE_COMPATIBLE,
                 .bit  = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
                 .name = "lazy refcounts",
@@ -3287,6 +3351,7 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
     uint64_t* refcount_table;
     Error *local_err = NULL;
     int ret;
+    uint8_t compression_type = QCOW2_COMPRESSION_TYPE_ZLIB;
 
     assert(create_options->driver == BLOCKDEV_DRIVER_QCOW2);
     qcow2_opts = &create_options->u.qcow2;
@@ -3404,6 +3469,31 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
         }
     }
 
+    if (qcow2_opts->has_compression_type &&
+        qcow2_opts->compression_type != QCOW2_COMPRESSION_TYPE_ZLIB) {
+
+        ret = -EINVAL;
+
+        if (version < 3) {
+            error_setg(errp, "Non-zlib compression type is only supported with "
+                       "compatibility level 1.1 and above (use version=v3 or "
+                       "greater)");
+            goto out;
+        }
+
+        switch (qcow2_opts->compression_type) {
+#ifdef CONFIG_ZSTD
+        case QCOW2_COMPRESSION_TYPE_ZSTD:
+            break;
+#endif
+        default:
+            error_setg(errp, "Unknown compression type");
+            goto out;
+        }
+
+        compression_type = qcow2_opts->compression_type;
+    }
+
     /* Create BlockBackend to write to the image */
     blk = blk_new_with_bs(bs, BLK_PERM_WRITE | BLK_PERM_RESIZE, BLK_PERM_ALL,
                           errp);
@@ -3426,6 +3516,8 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
         .refcount_table_offset      = cpu_to_be64(cluster_size),
         .refcount_table_clusters    = cpu_to_be32(1),
         .refcount_order             = cpu_to_be32(refcount_order),
+        /* don't deal with endianness since compression_type is 1 byte long */
+        .compression_type           = compression_type,
         .header_length              = cpu_to_be32(sizeof(*header)),
     };
 
@@ -3444,6 +3536,10 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp)
         header->autoclear_features |=
             cpu_to_be64(QCOW2_AUTOCLEAR_DATA_FILE_RAW);
     }
+    if (compression_type != QCOW2_COMPRESSION_TYPE_ZLIB) {
+        header->incompatible_features |=
+            cpu_to_be64(QCOW2_INCOMPAT_COMPRESSION);
+    }
 
     ret = blk_pwrite(blk, 0, header, cluster_size, 0);
     g_free(header);
@@ -3629,6 +3725,7 @@ static int coroutine_fn qcow2_co_create_opts(BlockDriver *drv,
         { BLOCK_OPT_ENCRYPT,            BLOCK_OPT_ENCRYPT_FORMAT },
         { BLOCK_OPT_COMPAT_LEVEL,       "version" },
         { BLOCK_OPT_DATA_FILE_RAW,      "data-file-raw" },
+        { BLOCK_OPT_COMPRESSION_TYPE,   "compression-type" },
         { NULL, NULL },
     };
 
@@ -4925,6 +5022,7 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs,
             .data_file          = g_strdup(s->image_data_file),
             .has_data_file_raw  = has_data_file(bs),
             .data_file_raw      = data_file_is_raw(bs),
+            .compression_type   = s->compression_type,
         };
     } else {
         /* if this assertion fails, this probably means a new version was
@@ -5330,6 +5428,22 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,
                                  "images");
                 return -EINVAL;
             }
+        } else if (!strcmp(desc->name, BLOCK_OPT_COMPRESSION_TYPE)) {
+            const char *ct_name =
+                qemu_opt_get(opts, BLOCK_OPT_COMPRESSION_TYPE);
+            int compression_type =
+                qapi_enum_parse(&Qcow2CompressionType_lookup, ct_name, -1,
+                                NULL);
+            if (compression_type == -1) {
+                error_setg(errp, "Unknown compression type: %s", ct_name);
+                return -ENOTSUP;
+            }
+
+            if (compression_type != s->compression_type) {
+                error_setg(errp, "Changing the compression type "
+                                 "is not supported");
+                return -ENOTSUP;
+            }
         } else {
             /* if this point is reached, this probably means a new option was
              * added without having it covered here */
@@ -5596,6 +5710,12 @@ static QemuOptsList qcow2_create_opts = {
             .help = "Width of a reference count entry in bits",
             .def_value_str = "16"
         },
+        {
+            .name = BLOCK_OPT_COMPRESSION_TYPE,
+            .type = QEMU_OPT_STRING,
+            .help = "Compression method used for image cluster compression",
+            .def_value_str = "zlib"
+        },
         { /* end of list */ }
     }
 };
diff --git a/block/qcow2.h b/block/qcow2.h
index f4de0a27d5..6a8b82e6cc 100644
--- a/block/qcow2.h
+++ b/block/qcow2.h
@@ -146,8 +146,16 @@ typedef struct QCowHeader {
 
     uint32_t refcount_order;
     uint32_t header_length;
+
+    /* Additional fields */
+    uint8_t compression_type;
+
+    /* header must be a multiple of 8 */
+    uint8_t padding[7];
 } QEMU_PACKED QCowHeader;
 
+QEMU_BUILD_BUG_ON(!QEMU_IS_ALIGNED(sizeof(QCowHeader), 8));
+
 typedef struct QEMU_PACKED QCowSnapshotHeader {
     /* header is 8 byte aligned */
     uint64_t l1_table_offset;
@@ -216,13 +224,16 @@ enum {
     QCOW2_INCOMPAT_DIRTY_BITNR      = 0,
     QCOW2_INCOMPAT_CORRUPT_BITNR    = 1,
     QCOW2_INCOMPAT_DATA_FILE_BITNR  = 2,
+    QCOW2_INCOMPAT_COMPRESSION_BITNR = 3,
     QCOW2_INCOMPAT_DIRTY            = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
     QCOW2_INCOMPAT_CORRUPT          = 1 << QCOW2_INCOMPAT_CORRUPT_BITNR,
     QCOW2_INCOMPAT_DATA_FILE        = 1 << QCOW2_INCOMPAT_DATA_FILE_BITNR,
+    QCOW2_INCOMPAT_COMPRESSION      = 1 << QCOW2_INCOMPAT_COMPRESSION_BITNR,
 
     QCOW2_INCOMPAT_MASK             = QCOW2_INCOMPAT_DIRTY
                                     | QCOW2_INCOMPAT_CORRUPT
-                                    | QCOW2_INCOMPAT_DATA_FILE,
+                                    | QCOW2_INCOMPAT_DATA_FILE
+                                    | QCOW2_INCOMPAT_COMPRESSION,
 };
 
 /* Compatible feature bits */
@@ -366,6 +377,13 @@ typedef struct BDRVQcow2State {
 
     bool metadata_preallocation_checked;
     bool metadata_preallocation;
+    /*
+     * Compression type used for the image. Default: 0 - ZLIB
+     * The image compression type is set on image creation.
+     * For now, the only way to change the compression type
+     * is to convert the image with the desired compression type set.
+     */
+    Qcow2CompressionType compression_type;
 } BDRVQcow2State;
 
 typedef struct Qcow2COWRegion {
diff --git a/configure b/configure
index 0d69c360c0..c50c006b86 100755
--- a/configure
+++ b/configure
@@ -1861,7 +1861,7 @@ disabled with --disable-FEATURE, default is enabled if available:
   lzfse           support of lzfse compression library
                   (for reading lzfse-compressed dmg images)
   zstd            support for zstd compression library
-                  (for migration compression)
+                  (for migration compression and qcow2 cluster compression)
   seccomp         seccomp support
   coroutine-pool  coroutine freelist (better performance)
   glusterfs       GlusterFS backend
diff --git a/docs/interop/qcow2.txt b/docs/interop/qcow2.txt
index 298a031310..cb723463f2 100644
--- a/docs/interop/qcow2.txt
+++ b/docs/interop/qcow2.txt
@@ -212,6 +212,7 @@ version 2.
 
                     Available compression type values:
                         0: zlib <https://www.zlib.net/>
+                        1: zstd <http://github.com/facebook/zstd>
 
 
 === Header padding ===
diff --git a/include/block/block_int.h b/include/block/block_int.h
index df6d0273d6..7ba8c89036 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -57,6 +57,7 @@
 #define BLOCK_OPT_REFCOUNT_BITS     "refcount_bits"
 #define BLOCK_OPT_DATA_FILE         "data_file"
 #define BLOCK_OPT_DATA_FILE_RAW     "data_file_raw"
+#define BLOCK_OPT_COMPRESSION_TYPE  "compression_type"
 
 #define BLOCK_PROBE_BUF_SIZE        512
 
diff --git a/qapi/block-core.json b/qapi/block-core.json
index 943df1926a..6fbacddab2 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -78,6 +78,8 @@
 #
 # @bitmaps: A list of qcow2 bitmap details (since 4.0)
 #
+# @compression-type: the image cluster compression method (since 5.1)
+#
 # Since: 1.7
 ##
 { 'struct': 'ImageInfoSpecificQCow2',
@@ -89,7 +91,8 @@
       '*corrupt': 'bool',
       'refcount-bits': 'int',
       '*encrypt': 'ImageInfoSpecificQCow2Encryption',
-      '*bitmaps': ['Qcow2BitmapInfo']
+      '*bitmaps': ['Qcow2BitmapInfo'],
+      'compression-type': 'Qcow2CompressionType'
   } }
 
 ##
@@ -4285,6 +4288,19 @@
 
 
 ##
+# @Qcow2CompressionType:
+#
+# Compression type used in qcow2 image file
+#
+# @zlib: zlib compression, see <http://zlib.net/>
+# @zstd: zstd compression, see <http://github.com/facebook/zstd>
+#
+# Since: 5.1
+##
+{ 'enum': 'Qcow2CompressionType',
+  'data': [ 'zlib', { 'name': 'zstd', 'if': 'defined(CONFIG_ZSTD)' } ] }
+
+##
 # @BlockdevCreateOptionsQcow2:
 #
 # Driver specific image creation options for qcow2.
@@ -4307,6 +4323,8 @@
 #                 allowed values: off, falloc, full, metadata)
 # @lazy-refcounts: True if refcounts may be updated lazily (default: off)
 # @refcount-bits: Width of reference counts in bits (default: 16)
+# @compression-type: The image cluster compression method
+#                    (default: zlib, since 5.1)
 #
 # Since: 2.12
 ##
@@ -4322,7 +4340,8 @@
             '*cluster-size':    'size',
             '*preallocation':   'PreallocMode',
             '*lazy-refcounts':  'bool',
-            '*refcount-bits':   'int' } }
+            '*refcount-bits':   'int',
+            '*compression-type':'Qcow2CompressionType' } }
 
 ##
 # @BlockdevCreateOptionsQed:
diff --git a/tests/qemu-iotests/031.out b/tests/qemu-iotests/031.out
index 46f97c5a4e..5a4beda6a2 100644
--- a/tests/qemu-iotests/031.out
+++ b/tests/qemu-iotests/031.out
@@ -113,11 +113,11 @@ incompatible_features     []
 compatible_features       []
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 Header extension:
@@ -146,11 +146,11 @@ incompatible_features     []
 compatible_features       []
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 Header extension:
@@ -164,7 +164,7 @@ No errors were found on the image.
 
 magic                     0x514649fb
 version                   3
-backing_file_offset       0x1d8
+backing_file_offset       0x210
 backing_file_size         0x17
 cluster_bits              16
 size                      67108864
@@ -179,7 +179,7 @@ incompatible_features     []
 compatible_features       []
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0xe2792aca
@@ -188,7 +188,7 @@ data                      'host_device'
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 Header extension:
diff --git a/tests/qemu-iotests/036.out b/tests/qemu-iotests/036.out
index 23b699ce06..e409acf60e 100644
--- a/tests/qemu-iotests/036.out
+++ b/tests/qemu-iotests/036.out
@@ -26,7 +26,7 @@ compatible_features       []
 autoclear_features        [63]
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 
@@ -38,7 +38,7 @@ compatible_features       []
 autoclear_features        []
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 *** done
diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out
index affa55b341..a5cfba1756 100644
--- a/tests/qemu-iotests/049.out
+++ b/tests/qemu-iotests/049.out
@@ -4,90 +4,90 @@ QA output created by 049
 == 1. Traditional size parameter ==
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1024
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1024b
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1k
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1K
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1048576 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1048576 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1G
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1073741824 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1073741824 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1T
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1099511627776 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1099511627776 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1024.0
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1024.0b
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1.5k
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1.5K
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1.5M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1572864 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1572864 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1.5G
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1610612736 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1610612736 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 TEST_DIR/t.qcow2 1.5T
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1649267441664 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1649267441664 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == 2. Specifying size via -o ==
 
 qemu-img create -f qcow2 -o size=1024 TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1024b TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1k TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1K TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1M TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1048576 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1048576 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1G TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1073741824 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1073741824 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1T TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1099511627776 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1099511627776 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1024.0 TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1024.0b TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1024 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1.5k TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1.5K TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1536 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1.5M TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1572864 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1572864 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1.5G TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1610612736 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1610612736 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o size=1.5T TEST_DIR/t.qcow2
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1649267441664 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=1649267441664 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == 3. Invalid sizes ==
 
@@ -129,84 +129,84 @@ qemu-img: TEST_DIR/t.qcow2: The image size must be specified only once
 == Check correct interpretation of suffixes for cluster size ==
 
 qemu-img create -f qcow2 -o cluster_size=1024 TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1024b TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1k TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1K TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1M TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1048576 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1048576 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1024.0 TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=1024.0b TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=1024 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=0.5k TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=512 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=512 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=0.5K TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=512 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=512 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o cluster_size=0.5M TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=524288 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=524288 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == Check compat level option ==
 
 qemu-img create -f qcow2 -o compat=0.10 TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=1.1 TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=0.42 TEST_DIR/t.qcow2 64M
 qemu-img: TEST_DIR/t.qcow2: Invalid parameter '0.42'
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.42 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.42 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=foobar TEST_DIR/t.qcow2 64M
 qemu-img: TEST_DIR/t.qcow2: Invalid parameter 'foobar'
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=foobar cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=foobar cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == Check preallocation option ==
 
 qemu-img create -f qcow2 -o preallocation=off TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=off lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=off lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o preallocation=metadata TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=metadata lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=metadata lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o preallocation=1234 TEST_DIR/t.qcow2 64M
 qemu-img: TEST_DIR/t.qcow2: Invalid parameter '1234'
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=1234 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 cluster_size=65536 preallocation=1234 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == Check encryption option ==
 
 qemu-img create -f qcow2 -o encryption=off TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 encryption=off cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 --object secret,id=sec0,data=123456 -o encryption=on,encrypt.key-secret=sec0 TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 encryption=on encrypt.key-secret=sec0 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 encryption=on encrypt.key-secret=sec0 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 == Check lazy_refcounts option (only with v3) ==
 
 qemu-img create -f qcow2 -o compat=1.1,lazy_refcounts=off TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=1.1,lazy_refcounts=on TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=on refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=1.1 cluster_size=65536 lazy_refcounts=on refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=0.10,lazy_refcounts=off TEST_DIR/t.qcow2 64M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 qemu-img create -f qcow2 -o compat=0.10,lazy_refcounts=on TEST_DIR/t.qcow2 64M
 qemu-img: TEST_DIR/t.qcow2: Lazy refcounts only supported with compatibility level 1.1 and above (use version=v3 or greater)
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=on refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 compat=0.10 cluster_size=65536 lazy_refcounts=on refcount_bits=16 compression_type=zlib
 
 *** done
diff --git a/tests/qemu-iotests/060.out b/tests/qemu-iotests/060.out
index 09caaea865..be5f8707a3 100644
--- a/tests/qemu-iotests/060.out
+++ b/tests/qemu-iotests/060.out
@@ -17,6 +17,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: true
diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out
index 5a8d36d005..a51ad1b5ba 100644
--- a/tests/qemu-iotests/061.out
+++ b/tests/qemu-iotests/061.out
@@ -22,11 +22,11 @@ incompatible_features     []
 compatible_features       [0]
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 magic                     0x514649fb
@@ -80,11 +80,11 @@ incompatible_features     []
 compatible_features       [0]
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 magic                     0x514649fb
@@ -136,11 +136,11 @@ incompatible_features     [0]
 compatible_features       [0]
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 ERROR cluster 5 refcount=0 reference=1
@@ -191,11 +191,11 @@ incompatible_features     []
 compatible_features       [42]
 autoclear_features        [42]
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 magic                     0x514649fb
@@ -260,11 +260,11 @@ incompatible_features     []
 compatible_features       [0]
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 read 65536/65536 bytes at offset 44040192
@@ -322,11 +322,11 @@ incompatible_features     [0]
 compatible_features       [0]
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 ERROR cluster 5 refcount=0 reference=1
@@ -351,11 +351,11 @@ incompatible_features     []
 compatible_features       []
 autoclear_features        []
 refcount_order            4
-header_length             104
+header_length             112
 
 Header extension:
 magic                     0x6803f857
-length                    288
+length                    336
 data                      <binary>
 
 read 131072/131072 bytes at offset 0
@@ -519,6 +519,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file: TEST_DIR/t.IMGFMT.data
@@ -539,6 +540,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file: foo
@@ -552,6 +554,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file raw: false
@@ -566,6 +569,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file: TEST_DIR/t.IMGFMT.data
@@ -578,6 +582,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file: TEST_DIR/t.IMGFMT.data
@@ -591,6 +596,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     data file: TEST_DIR/t.IMGFMT.data
diff --git a/tests/qemu-iotests/065 b/tests/qemu-iotests/065
index 6426474271..18dc488c7a 100755
--- a/tests/qemu-iotests/065
+++ b/tests/qemu-iotests/065
@@ -88,24 +88,30 @@ class TestQMP(TestImageInfoSpecific):
 class TestQCow2(TestQemuImgInfo):
     '''Testing a qcow2 version 2 image'''
     img_options = 'compat=0.10'
-    json_compare = { 'compat': '0.10', 'refcount-bits': 16 }
-    human_compare = [ 'compat: 0.10', 'refcount bits: 16' ]
+    json_compare = { 'compat': '0.10', 'refcount-bits': 16,
+                     'compression-type': 'zlib' }
+    human_compare = [ 'compat: 0.10', 'compression type: zlib',
+                      'refcount bits: 16' ]
 
 class TestQCow3NotLazy(TestQemuImgInfo):
     '''Testing a qcow2 version 3 image with lazy refcounts disabled'''
     img_options = 'compat=1.1,lazy_refcounts=off'
     json_compare = { 'compat': '1.1', 'lazy-refcounts': False,
-                     'refcount-bits': 16, 'corrupt': False }
-    human_compare = [ 'compat: 1.1', 'lazy refcounts: false',
-                      'refcount bits: 16', 'corrupt: false' ]
+                     'refcount-bits': 16, 'corrupt': False,
+                     'compression-type': 'zlib' }
+    human_compare = [ 'compat: 1.1', 'compression type: zlib',
+                      'lazy refcounts: false', 'refcount bits: 16',
+                      'corrupt: false' ]
 
 class TestQCow3Lazy(TestQemuImgInfo):
     '''Testing a qcow2 version 3 image with lazy refcounts enabled'''
     img_options = 'compat=1.1,lazy_refcounts=on'
     json_compare = { 'compat': '1.1', 'lazy-refcounts': True,
-                     'refcount-bits': 16, 'corrupt': False }
-    human_compare = [ 'compat: 1.1', 'lazy refcounts: true',
-                      'refcount bits: 16', 'corrupt: false' ]
+                     'refcount-bits': 16, 'corrupt': False,
+                     'compression-type': 'zlib' }
+    human_compare = [ 'compat: 1.1', 'compression type: zlib',
+                      'lazy refcounts: true', 'refcount bits: 16',
+                      'corrupt: false' ]
 
 class TestQCow3NotLazyQMP(TestQMP):
     '''Testing a qcow2 version 3 image with lazy refcounts disabled, opening
@@ -113,7 +119,8 @@ class TestQCow3NotLazyQMP(TestQMP):
     img_options = 'compat=1.1,lazy_refcounts=off'
     qemu_options = 'lazy-refcounts=on'
     compare = { 'compat': '1.1', 'lazy-refcounts': False,
-                'refcount-bits': 16, 'corrupt': False }
+                'refcount-bits': 16, 'corrupt': False,
+                'compression-type': 'zlib' }
 
 
 class TestQCow3LazyQMP(TestQMP):
@@ -122,7 +129,8 @@ class TestQCow3LazyQMP(TestQMP):
     img_options = 'compat=1.1,lazy_refcounts=on'
     qemu_options = 'lazy-refcounts=off'
     compare = { 'compat': '1.1', 'lazy-refcounts': True,
-                'refcount-bits': 16, 'corrupt': False }
+                'refcount-bits': 16, 'corrupt': False,
+                'compression-type': 'zlib' }
 
 TestImageInfoSpecific = None
 TestQemuImgInfo = None
diff --git a/tests/qemu-iotests/080 b/tests/qemu-iotests/080
index a3d13c414e..7588c63b6c 100755
--- a/tests/qemu-iotests/080
+++ b/tests/qemu-iotests/080
@@ -45,7 +45,7 @@ _supported_os Linux
 # - This is generally a test for compat=1.1 images
 _unsupported_imgopts 'refcount_bits=1[^0-9]' data_file 'compat=0.10'
 
-header_size=104
+header_size=112
 
 offset_backing_file_offset=8
 offset_backing_file_size=16
diff --git a/tests/qemu-iotests/082.out b/tests/qemu-iotests/082.out
index 9d4ed4dc9d..529a1214e1 100644
--- a/tests/qemu-iotests/082.out
+++ b/tests/qemu-iotests/082.out
@@ -3,38 +3,40 @@ QA output created by 082
 === create: Options specified more than once ===
 
 Testing: create -f foo -f qcow2 TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 128 MiB (134217728 bytes)
 cluster_size: 65536
 
 Testing: create -f qcow2 -o cluster_size=4k -o lazy_refcounts=on TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=4096 lazy_refcounts=on refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=4096 lazy_refcounts=on refcount_bits=16 compression_type=zlib
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 128 MiB (134217728 bytes)
 cluster_size: 4096
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
 
 Testing: create -f qcow2 -o cluster_size=4k -o lazy_refcounts=on -o cluster_size=8k TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=8192 lazy_refcounts=on refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=8192 lazy_refcounts=on refcount_bits=16 compression_type=zlib
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 128 MiB (134217728 bytes)
 cluster_size: 8192
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
 
 Testing: create -f qcow2 -o cluster_size=4k,cluster_size=8k TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=8192 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=8192 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 128 MiB (134217728 bytes)
@@ -48,6 +50,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -71,6 +74,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -94,6 +98,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -117,6 +122,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -140,6 +146,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -163,6 +170,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -186,6 +194,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -209,6 +218,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -227,10 +237,10 @@ Supported options:
   size=<size>            - Virtual disk size
 
 Testing: create -f qcow2 -u -o backing_file=TEST_DIR/t.qcow2,,help TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2,,help cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2,,help cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 Testing: create -f qcow2 -u -o backing_file=TEST_DIR/t.qcow2,,? TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2,,? cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2,,? cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 Testing: create -f qcow2 -o backing_file=TEST_DIR/t.qcow2, -o help TEST_DIR/t.qcow2 128M
 qemu-img: Invalid option list: backing_file=TEST_DIR/t.qcow2,
@@ -247,6 +257,7 @@ Supported qcow2 options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -279,7 +290,7 @@ qemu-img: Format driver 'bochs' does not support image creation
 === convert: Options specified more than once ===
 
 Testing: create -f qcow2 TEST_DIR/t.qcow2 128M
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 Testing: convert -f foo -f qcow2 TEST_DIR/t.qcow2 TEST_DIR/t.qcow2.base
 image: TEST_DIR/t.IMGFMT.base
@@ -299,6 +310,7 @@ virtual size: 128 MiB (134217728 bytes)
 cluster_size: 4096
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
@@ -310,6 +322,7 @@ virtual size: 128 MiB (134217728 bytes)
 cluster_size: 8192
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
@@ -328,6 +341,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -351,6 +365,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -374,6 +389,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -397,6 +413,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -420,6 +437,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -443,6 +461,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -466,6 +485,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -489,6 +509,7 @@ Supported options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -527,6 +548,7 @@ Supported qcow2 options:
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -579,6 +601,7 @@ virtual size: 128 MiB (134217728 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
@@ -590,6 +613,7 @@ virtual size: 130 MiB (136314880 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -601,6 +625,7 @@ virtual size: 132 MiB (138412032 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 16
     corrupt: false
@@ -619,6 +644,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -643,6 +669,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -667,6 +694,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -691,6 +719,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -715,6 +744,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -739,6 +769,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -763,6 +794,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -787,6 +819,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
@@ -828,6 +861,7 @@ Creation options for 'qcow2':
   backing_fmt=<str>      - Image format of the base image
   cluster_size=<size>    - qcow2 cluster size
   compat=<str>           - Compatibility level (v2 [0.10] or v3 [1.1])
+  compression_type=<str> - Compression method used for image cluster compression
   data_file=<str>        - File name of an external data file
   data_file_raw=<bool (on/off)> - The external data file must stay valid as a raw image
   encrypt.cipher-alg=<str> - Name of encryption cipher algorithm
diff --git a/tests/qemu-iotests/085.out b/tests/qemu-iotests/085.out
index fd11aae678..a822ff4ef6 100644
--- a/tests/qemu-iotests/085.out
+++ b/tests/qemu-iotests/085.out
@@ -13,7 +13,7 @@ Formatting 'TEST_DIR/t.IMGFMT.2', fmt=IMGFMT size=134217728
 === Create a single snapshot on virtio0 ===
 
 { 'execute': 'blockdev-snapshot-sync', 'arguments': { 'device': 'virtio0', 'snapshot-file':'TEST_DIR/1-snapshot-v0.IMGFMT', 'format': 'IMGFMT' } }
-Formatting 'TEST_DIR/1-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2.1 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/1-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2.1 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 
 === Invalid command - missing device and nodename ===
@@ -30,40 +30,40 @@ Formatting 'TEST_DIR/1-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file
 === Create several transactional group snapshots ===
 
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/2-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/2-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/2-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/1-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/2-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2.2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/2-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/1-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/2-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/t.qcow2.2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/3-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/3-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/3-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/2-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/3-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/2-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/3-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/2-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/3-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/2-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/4-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/4-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/4-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/3-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/4-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/3-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/4-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/3-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/4-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/3-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/5-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/5-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/5-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/4-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/5-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/4-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/5-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/4-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/5-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/4-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/6-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/6-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/6-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/5-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/6-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/5-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/6-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/5-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/6-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/5-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/7-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/7-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/7-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/6-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/7-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/6-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/7-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/6-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/7-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/6-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/8-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/8-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/8-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/7-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/8-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/7-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/8-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/7-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/8-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/7-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/9-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/9-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/9-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/8-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/9-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/8-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/9-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/8-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/9-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/8-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'transaction', 'arguments': {'actions': [ { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio0', 'snapshot-file': 'TEST_DIR/10-snapshot-v0.IMGFMT' } }, { 'type': 'blockdev-snapshot-sync', 'data' : { 'device': 'virtio1', 'snapshot-file': 'TEST_DIR/10-snapshot-v1.IMGFMT' } } ] } }
-Formatting 'TEST_DIR/10-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/9-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
-Formatting 'TEST_DIR/10-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/9-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/10-snapshot-v0.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/9-snapshot-v0.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
+Formatting 'TEST_DIR/10-snapshot-v1.qcow2', fmt=qcow2 size=134217728 backing_file=TEST_DIR/9-snapshot-v1.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 
 === Create a couple of snapshots using blockdev-snapshot ===
diff --git a/tests/qemu-iotests/144.out b/tests/qemu-iotests/144.out
index c7aa2e4820..885a8874a5 100644
--- a/tests/qemu-iotests/144.out
+++ b/tests/qemu-iotests/144.out
@@ -9,7 +9,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=536870912
 { 'execute': 'qmp_capabilities' }
 {"return": {}}
 { 'execute': 'blockdev-snapshot-sync', 'arguments': { 'device': 'virtio0', 'snapshot-file':'TEST_DIR/tmp.IMGFMT', 'format': 'IMGFMT' } }
-Formatting 'TEST_DIR/tmp.qcow2', fmt=qcow2 size=536870912 backing_file=TEST_DIR/t.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/tmp.qcow2', fmt=qcow2 size=536870912 backing_file=TEST_DIR/t.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 
 === Performing block-commit on active layer ===
@@ -31,6 +31,6 @@ Formatting 'TEST_DIR/tmp.qcow2', fmt=qcow2 size=536870912 backing_file=TEST_DIR/
 === Performing Live Snapshot 2 ===
 
 { 'execute': 'blockdev-snapshot-sync', 'arguments': { 'device': 'virtio0', 'snapshot-file':'TEST_DIR/tmp2.IMGFMT', 'format': 'IMGFMT' } }
-Formatting 'TEST_DIR/tmp2.qcow2', fmt=qcow2 size=536870912 backing_file=TEST_DIR/t.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/tmp2.qcow2', fmt=qcow2 size=536870912 backing_file=TEST_DIR/t.qcow2 backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 *** done
diff --git a/tests/qemu-iotests/182.out b/tests/qemu-iotests/182.out
index a8eea166c3..ae43654d32 100644
--- a/tests/qemu-iotests/182.out
+++ b/tests/qemu-iotests/182.out
@@ -13,7 +13,7 @@ Is another process using the image [TEST_DIR/t.qcow2]?
 {'execute': 'blockdev-add', 'arguments': { 'node-name': 'node0', 'driver': 'file', 'filename': 'TEST_DIR/t.IMGFMT', 'locking': 'on' } }
 {"return": {}}
 {'execute': 'blockdev-snapshot-sync', 'arguments': { 'node-name': 'node0', 'snapshot-file': 'TEST_DIR/t.IMGFMT.overlay', 'snapshot-node-name': 'node1' } }
-Formatting 'TEST_DIR/t.qcow2.overlay', fmt=qcow2 size=197120 backing_file=TEST_DIR/t.qcow2 backing_fmt=file cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2.overlay', fmt=qcow2 size=197120 backing_file=TEST_DIR/t.qcow2 backing_fmt=file cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 {'execute': 'blockdev-add', 'arguments': { 'node-name': 'node1', 'driver': 'file', 'filename': 'TEST_DIR/t.IMGFMT', 'locking': 'on' } }
 {"return": {}}
diff --git a/tests/qemu-iotests/185.out b/tests/qemu-iotests/185.out
index 9a3b65782b..ac5ab16bc8 100644
--- a/tests/qemu-iotests/185.out
+++ b/tests/qemu-iotests/185.out
@@ -9,14 +9,14 @@ Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864
 === Creating backing chain ===
 
 { 'execute': 'blockdev-snapshot-sync', 'arguments': { 'device': 'disk', 'snapshot-file': 'TEST_DIR/t.IMGFMT.mid', 'format': 'IMGFMT', 'mode': 'absolute-paths' } }
-Formatting 'TEST_DIR/t.qcow2.mid', fmt=qcow2 size=67108864 backing_file=TEST_DIR/t.qcow2.base backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2.mid', fmt=qcow2 size=67108864 backing_file=TEST_DIR/t.qcow2.base backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 { 'execute': 'human-monitor-command', 'arguments': { 'command-line': 'qemu-io disk "write 0 4M"' } }
 wrote 4194304/4194304 bytes at offset 0
 4 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {"return": ""}
 { 'execute': 'blockdev-snapshot-sync', 'arguments': { 'device': 'disk', 'snapshot-file': 'TEST_DIR/t.IMGFMT', 'format': 'IMGFMT', 'mode': 'absolute-paths' } }
-Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 backing_file=TEST_DIR/t.qcow2.mid backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 backing_file=TEST_DIR/t.qcow2.mid backing_fmt=qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"return": {}}
 
 === Start commit job and exit qemu ===
@@ -48,7 +48,7 @@ Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 size=67108864 backing_file=TEST_DIR/t.q
 { 'execute': 'qmp_capabilities' }
 {"return": {}}
 { 'execute': 'drive-mirror', 'arguments': { 'device': 'disk', 'target': 'TEST_DIR/t.IMGFMT.copy', 'format': 'IMGFMT', 'sync': 'full', 'speed': 65536 } }
-Formatting 'TEST_DIR/t.qcow2.copy', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2.copy', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "created", "id": "disk"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "running", "id": "disk"}}
 {"return": {}}
@@ -62,7 +62,7 @@ Formatting 'TEST_DIR/t.qcow2.copy', fmt=qcow2 size=67108864 cluster_size=65536 l
 { 'execute': 'qmp_capabilities' }
 {"return": {}}
 { 'execute': 'drive-backup', 'arguments': { 'device': 'disk', 'target': 'TEST_DIR/t.IMGFMT.copy', 'format': 'IMGFMT', 'sync': 'full', 'speed': 65536 } }
-Formatting 'TEST_DIR/t.qcow2.copy', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/t.qcow2.copy', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "created", "id": "disk"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "running", "id": "disk"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "paused", "id": "disk"}}
diff --git a/tests/qemu-iotests/198.out b/tests/qemu-iotests/198.out
index 831ce3a289..6280ae6eed 100644
--- a/tests/qemu-iotests/198.out
+++ b/tests/qemu-iotests/198.out
@@ -36,6 +36,7 @@ image: json:{ /* filtered */ }
 file format: IMGFMT
 virtual size: 16 MiB (16777216 bytes)
 Format specific information:
+    compression type: zlib
     encrypt:
         ivgen alg: plain64
         hash alg: sha256
@@ -79,6 +80,7 @@ file format: IMGFMT
 virtual size: 16 MiB (16777216 bytes)
 backing file: TEST_DIR/t.IMGFMT.base
 Format specific information:
+    compression type: zlib
     encrypt:
         ivgen alg: plain64
         hash alg: sha256
diff --git a/tests/qemu-iotests/206.out b/tests/qemu-iotests/206.out
index 61e7241e0b..1a14255a83 100644
--- a/tests/qemu-iotests/206.out
+++ b/tests/qemu-iotests/206.out
@@ -18,6 +18,7 @@ virtual size: 128 MiB (134217728 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -40,6 +41,7 @@ virtual size: 64 MiB (67108864 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -62,6 +64,7 @@ virtual size: 32 MiB (33554432 bytes)
 cluster_size: 2097152
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: true
     refcount bits: 1
     corrupt: false
@@ -86,6 +89,7 @@ backing file: TEST_IMG.base
 backing file format: IMGFMT
 Format specific information:
     compat: 0.10
+    compression type: zlib
     refcount bits: 16
 
 === Successful image creation (encrypted) ===
@@ -102,6 +106,7 @@ encrypted: yes
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     encrypt:
diff --git a/tests/qemu-iotests/242.out b/tests/qemu-iotests/242.out
index 7ac8404d11..091b9126ce 100644
--- a/tests/qemu-iotests/242.out
+++ b/tests/qemu-iotests/242.out
@@ -12,6 +12,7 @@ virtual size: 1 MiB (1048576 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -32,6 +33,7 @@ virtual size: 1 MiB (1048576 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     bitmaps:
         [0]:
@@ -64,6 +66,7 @@ virtual size: 1 MiB (1048576 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     bitmaps:
         [0]:
@@ -104,6 +107,7 @@ virtual size: 1 MiB (1048576 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     bitmaps:
         [0]:
@@ -153,6 +157,7 @@ virtual size: 1 MiB (1048576 bytes)
 cluster_size: 65536
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     bitmaps:
         [0]:
diff --git a/tests/qemu-iotests/255.out b/tests/qemu-iotests/255.out
index 348909fdef..a3c99fd62e 100644
--- a/tests/qemu-iotests/255.out
+++ b/tests/qemu-iotests/255.out
@@ -3,9 +3,9 @@ Finishing a commit job with background reads
 
 === Create backing chain and start VM ===
 
-Formatting 'TEST_DIR/PID-t.qcow2.mid', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-t.qcow2.mid', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-t.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 === Start background read requests ===
 
@@ -23,9 +23,9 @@ Closing the VM while a job is being cancelled
 
 === Create images and start VM ===
 
-Formatting 'TEST_DIR/PID-src.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-src.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-dst.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-dst.qcow2', fmt=qcow2 size=134217728 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 1048576/1048576 bytes at offset 0
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
diff --git a/tests/qemu-iotests/274.out b/tests/qemu-iotests/274.out
index 9d6fdeb1f7..d24ff681af 100644
--- a/tests/qemu-iotests/274.out
+++ b/tests/qemu-iotests/274.out
@@ -1,9 +1,9 @@
 == Commit tests ==
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 2097152/2097152 bytes at offset 0
 2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -52,6 +52,7 @@ cluster_size: 65536
 backing file: TEST_DIR/PID-base
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -63,11 +64,11 @@ read 1048576/1048576 bytes at offset 1048576
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
 === Testing HMP commit (top -> mid) ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 2097152/2097152 bytes at offset 0
 2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -81,6 +82,7 @@ cluster_size: 65536
 backing file: TEST_DIR/PID-base
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -92,11 +94,11 @@ read 1048576/1048576 bytes at offset 1048576
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
 === Testing QMP active commit (top -> mid) ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=2097152 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-mid', fmt=qcow2 size=1048576 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=2097152 backing_file=TEST_DIR/PID-mid cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 2097152/2097152 bytes at offset 0
 2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -116,6 +118,7 @@ cluster_size: 65536
 backing file: TEST_DIR/PID-base
 Format specific information:
     compat: 1.1
+    compression type: zlib
     lazy refcounts: false
     refcount bits: 16
     corrupt: false
@@ -128,9 +131,9 @@ read 1048576/1048576 bytes at offset 1048576
 
 == Resize tests ==
 === preallocation=off ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=6442450944 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=6442450944 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=1073741824 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=1073741824 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 5368709120
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -147,9 +150,9 @@ read 65536/65536 bytes at offset 5368709120
 { "start": 1073741824, "length": 7516192768, "depth": 0, "zero": true, "data": false}]
 
 === preallocation=metadata ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=34359738368 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=34359738368 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=32212254720 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=32212254720 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 33285996544
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -171,9 +174,9 @@ read 65536/65536 bytes at offset 33285996544
 { "start": 34896609280, "length": 536870912, "depth": 0, "zero": true, "data": false, "offset": 2685075456}]
 
 === preallocation=falloc ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=10485760 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=10485760 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=5242880 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=5242880 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 9437184
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -190,9 +193,9 @@ read 65536/65536 bytes at offset 9437184
 { "start": 5242880, "length": 10485760, "depth": 0, "zero": false, "data": true, "offset": 327680}]
 
 === preallocation=full ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=16777216 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=16777216 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=8388608 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=8388608 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 11534336
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -209,9 +212,9 @@ read 65536/65536 bytes at offset 11534336
 { "start": 8388608, "length": 4194304, "depth": 0, "zero": false, "data": true, "offset": 327680}]
 
 === preallocation=off ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=393216 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=393216 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=259072 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=259072 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 259072
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -229,9 +232,9 @@ read 65536/65536 bytes at offset 259072
 { "start": 262144, "length": 262144, "depth": 0, "zero": true, "data": false}]
 
 === preallocation=off ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=409600 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=409600 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=262144 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=262144 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 344064
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -248,9 +251,9 @@ read 65536/65536 bytes at offset 344064
 { "start": 262144, "length": 262144, "depth": 0, "zero": true, "data": false}]
 
 === preallocation=off ===
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=524288 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=524288 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
-Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=262144 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-top', fmt=qcow2 size=262144 backing_file=TEST_DIR/PID-base cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 wrote 65536/65536 bytes at offset 446464
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
diff --git a/tests/qemu-iotests/280.out b/tests/qemu-iotests/280.out
index 5d382faaa8..92e4d14079 100644
--- a/tests/qemu-iotests/280.out
+++ b/tests/qemu-iotests/280.out
@@ -1,4 +1,4 @@
-Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16
+Formatting 'TEST_DIR/PID-base', fmt=qcow2 size=67108864 cluster_size=65536 lazy_refcounts=off refcount_bits=16 compression_type=zlib
 
 === Launch VM ===
 Enabling migration QMP events on VM...
diff --git a/tests/qemu-iotests/287 b/tests/qemu-iotests/287
new file mode 100755
index 0000000000..f98a4cadc1
--- /dev/null
+++ b/tests/qemu-iotests/287
@@ -0,0 +1,152 @@
+#!/usr/bin/env bash
+#
+# Test case for an image using zstd compression
+#
+# Copyright (c) 2020 Virtuozzo International GmbH
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+# creator
+owner=dplotnikov@virtuozzo.com
+
+seq="$(basename $0)"
+echo "QA output created by $seq"
+
+status=1	# failure is the default!
+
+# standard environment
+. ./common.rc
+. ./common.filter
+
+# This tests qocw2-specific low-level functionality
+_supported_fmt qcow2
+_supported_proto file
+_supported_os Linux
+_unsupported_imgopts 'compat=0.10' data_file
+
+COMPR_IMG="$TEST_IMG.compressed"
+RAND_FILE="$TEST_DIR/rand_data"
+
+_cleanup()
+{
+    _cleanup_test_img
+    _rm_test_img "$COMPR_IMG"
+    rm -f "$RAND_FILE"
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# for all the cases
+CLUSTER_SIZE=65536
+
+# Check if we can run this test.
+if IMGOPTS='compression_type=zstd' _make_test_img 64M |
+    grep "Invalid parameter 'zstd'"; then
+    _notrun "ZSTD is disabled"
+fi
+
+echo
+echo "=== Testing compression type incompatible bit setting for zlib ==="
+echo
+_make_test_img -o compression_type=zlib 64M
+$PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+echo
+echo "=== Testing compression type incompatible bit setting for zstd ==="
+echo
+_make_test_img -o compression_type=zstd 64M
+$PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+echo
+echo "=== Testing zlib with incompatible bit set ==="
+echo
+_make_test_img -o compression_type=zlib 64M
+$PYTHON qcow2.py "$TEST_IMG" set-feature-bit incompatible 3
+# to make sure the bit was actually set
+$PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+if $QEMU_IMG info "$TEST_IMG" >/dev/null 2>&1 ; then
+    echo "Error: The image opened successfully. The image must not be opened."
+fi
+
+echo
+echo "=== Testing zstd with incompatible bit unset ==="
+echo
+_make_test_img -o compression_type=zstd 64M
+$PYTHON qcow2.py "$TEST_IMG" set-header incompatible_features 0
+# to make sure the bit was actually unset
+$PYTHON qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
+
+if $QEMU_IMG info "$TEST_IMG" >/dev/null 2>&1 ; then
+    echo "Error: The image opened successfully. The image must not be opened."
+fi
+
+echo
+echo "=== Testing compression type values ==="
+echo
+# zlib=0
+_make_test_img -o compression_type=zlib 64M
+peek_file_be "$TEST_IMG" 104 1
+echo
+
+# zstd=1
+_make_test_img -o compression_type=zstd 64M
+peek_file_be "$TEST_IMG" 104 1
+echo
+
+echo
+echo "=== Testing simple reading and writing with zstd ==="
+echo
+_make_test_img -o compression_type=zstd 64M
+$QEMU_IO -c "write -c -P 0xAC 64K 64K " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0xAC 64K 64K " "$TEST_IMG" | _filter_qemu_io
+# read on the cluster boundaries
+$QEMU_IO -c "read -v 131070 8 " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -v 65534 8" "$TEST_IMG" | _filter_qemu_io
+
+echo
+echo "=== Testing adjacent clusters reading and writing with zstd ==="
+echo
+_make_test_img -o compression_type=zstd 64M
+$QEMU_IO -c "write -c -P 0xAB 0 64K " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "write -c -P 0xAC 64K 64K " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "write -c -P 0xAD 128K 64K " "$TEST_IMG" | _filter_qemu_io
+
+$QEMU_IO -c "read -P 0xAB 0 64k " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0xAC 64K 64k " "$TEST_IMG" | _filter_qemu_io
+$QEMU_IO -c "read -P 0xAD 128K 64k " "$TEST_IMG" | _filter_qemu_io
+
+echo
+echo "=== Testing incompressible cluster processing with zstd ==="
+echo
+# create a 2M image and fill it with 1M likely incompressible data
+# and 1M compressible data
+dd if=/dev/urandom of="$RAND_FILE" bs=1M count=1 seek=1
+QEMU_IO_OPTIONS="$QEMU_IO_OPTIONS_NO_FMT" \
+$QEMU_IO -f raw -c "write -P 0xFA 0 1M" "$RAND_FILE" | _filter_qemu_io
+
+$QEMU_IMG convert -f raw -O $IMGFMT -c \
+-o "$(_optstr_add "$IMGOPTS" "compression_type=zlib")" "$RAND_FILE" \
+"$TEST_IMG" | _filter_qemu_io
+
+$QEMU_IMG convert -O $IMGFMT -c \
+-o "$(_optstr_add "$IMGOPTS" "compression_type=zstd")" "$TEST_IMG" \
+"$COMPR_IMG" | _filter_qemu_io
+
+$QEMU_IMG compare "$TEST_IMG" "$COMPR_IMG"
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/287.out b/tests/qemu-iotests/287.out
new file mode 100644
index 0000000000..6b9dfb4af0
--- /dev/null
+++ b/tests/qemu-iotests/287.out
@@ -0,0 +1,67 @@
+QA output created by 287
+
+=== Testing compression type incompatible bit setting for zlib ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+incompatible_features     []
+
+=== Testing compression type incompatible bit setting for zstd ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+incompatible_features     [3]
+
+=== Testing zlib with incompatible bit set  ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+incompatible_features     [3]
+
+=== Testing zstd with incompatible bit unset  ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+incompatible_features     []
+
+=== Testing compression type values  ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+   0
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+   1
+
+=== Testing simple reading and writing with zstd ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+wrote 65536/65536 bytes at offset 65536
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 65536/65536 bytes at offset 65536
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+0001fffe:  ac ac 00 00 00 00 00 00  ........
+read 8/8 bytes at offset 131070
+8 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+0000fffe:  00 00 ac ac ac ac ac ac  ........
+read 8/8 bytes at offset 65534
+8 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Testing adjacent clusters reading and writing with zstd ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+wrote 65536/65536 bytes at offset 0
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 65536/65536 bytes at offset 65536
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 65536/65536 bytes at offset 131072
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 65536/65536 bytes at offset 0
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 65536/65536 bytes at offset 65536
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 65536/65536 bytes at offset 131072
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Testing incompressible cluster processing with zstd ===
+
+1+0 records in
+1+0 records out
+wrote 1048576/1048576 bytes at offset 0
+1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Images are identical.
+*** done
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index 3f8ee3e5f7..279e0bbb0d 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -152,7 +152,8 @@ _filter_img_create()
         -e "s# refcount_bits=[0-9]\\+##g" \
         -e "s# key-secret=[a-zA-Z0-9]\\+##g" \
         -e "s# iter-time=[0-9]\\+##g" \
-        -e "s# force_size=\\(on\\|off\\)##g"
+        -e "s# force_size=\\(on\\|off\\)##g" \
+        -e "s# compression_type=[a-zA-Z0-9]\\+##g"
 }
 
 _filter_img_info()
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index fe649c5b73..34175fd437 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -295,6 +295,7 @@
 283 auto quick
 284 rw
 286 rw quick
+287 auto quick
 288 quick
 289 rw quick
 290 rw auto quick