diff --git a/block.c b/block.c
index 874a29a983..5944124845 100644
--- a/block.c
+++ b/block.c
@@ -4165,7 +4165,6 @@ void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
 {
     BdrvChild *c, *next;
     GSList *list = NULL, *p;
-    uint64_t old_perm, old_shared;
     uint64_t perm = 0, shared = BLK_PERM_ALL;
     int ret;
 
@@ -4211,8 +4210,8 @@ void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
         bdrv_unref(from);
     }
 
-    bdrv_get_cumulative_perm(to, &old_perm, &old_shared);
-    bdrv_set_perm(to, old_perm | perm, old_shared | shared);
+    bdrv_get_cumulative_perm(to, &perm, &shared);
+    bdrv_set_perm(to, perm, shared);
 
 out:
     g_slist_free(list);
diff --git a/block/file-posix.c b/block/file-posix.c
index fbeb0068db..71f168ee2f 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -380,7 +380,7 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp)
         for (i = 0; i < ARRAY_SIZE(alignments); i++) {
             align = alignments[i];
             if (raw_is_io_aligned(fd, buf + align, max_align)) {
-                /* Fallback to request_aligment. */
+                /* Fallback to request_alignment. */
                 s->buf_align = (align != 1) ? align : bs->bl.request_alignment;
                 break;
             }
@@ -1749,6 +1749,43 @@ static int handle_aiocb_discard(void *opaque)
     return ret;
 }
 
+/*
+ * Help alignment probing by allocating the first block.
+ *
+ * When reading with direct I/O from unallocated area on Gluster backed by XFS,
+ * reading succeeds regardless of request length. In this case we fallback to
+ * safe alignment which is not optimal. Allocating the first block avoids this
+ * fallback.
+ *
+ * fd may be opened with O_DIRECT, but we don't know the buffer alignment or
+ * request alignment, so we use safe values.
+ *
+ * Returns: 0 on success, -errno on failure. Since this is an optimization,
+ * caller may ignore failures.
+ */
+static int allocate_first_block(int fd, size_t max_size)
+{
+    size_t write_size = (max_size < MAX_BLOCKSIZE)
+        ? BDRV_SECTOR_SIZE
+        : MAX_BLOCKSIZE;
+    size_t max_align = MAX(MAX_BLOCKSIZE, getpagesize());
+    void *buf;
+    ssize_t n;
+    int ret;
+
+    buf = qemu_memalign(max_align, write_size);
+    memset(buf, 0, write_size);
+
+    do {
+        n = pwrite(fd, buf, write_size, 0);
+    } while (n == -1 && errno == EINTR);
+
+    ret = (n == -1) ? -errno : 0;
+
+    qemu_vfree(buf);
+    return ret;
+}
+
 static int handle_aiocb_truncate(void *opaque)
 {
     RawPosixAIOData *aiocb = opaque;
@@ -1788,6 +1825,17 @@ static int handle_aiocb_truncate(void *opaque)
                 /* posix_fallocate() doesn't set errno. */
                 error_setg_errno(errp, -result,
                                  "Could not preallocate new data");
+            } else if (current_length == 0) {
+                /*
+                 * posix_fallocate() uses fallocate() if the filesystem
+                 * supports it, or fallback to manually writing zeroes. If
+                 * fallocate() was used, unaligned reads from the fallocated
+                 * area in raw_probe_alignment() will succeed, hence we need to
+                 * allocate the first block.
+                 *
+                 * Optimize future alignment probing; ignore failures.
+                 */
+                allocate_first_block(fd, offset);
             }
         } else {
             result = 0;
@@ -1849,6 +1897,9 @@ static int handle_aiocb_truncate(void *opaque)
         if (ftruncate(fd, offset) != 0) {
             result = -errno;
             error_setg_errno(errp, -result, "Could not resize file");
+        } else if (current_length == 0 && offset > current_length) {
+            /* Optimize future alignment probing; ignore failures. */
+            allocate_first_block(fd, offset);
         }
         return result;
     default:
diff --git a/block/vmdk.c b/block/vmdk.c
index fd78fd0ccf..fed3b50c8a 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -1076,8 +1076,7 @@ static const char *next_line(const char *s)
 }
 
 static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
-                              const char *desc_file_path, QDict *options,
-                              Error **errp)
+                              QDict *options, Error **errp)
 {
     int ret;
     int matches;
@@ -1087,6 +1086,7 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
     const char *p, *np;
     int64_t sectors = 0;
     int64_t flat_offset;
+    char *desc_file_dir = NULL;
     char *extent_path;
     BdrvChild *extent_file;
     BDRVVmdkState *s = bs->opaque;
@@ -1130,16 +1130,23 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
             continue;
         }
 
-        if (!path_is_absolute(fname) && !path_has_protocol(fname) &&
-            !desc_file_path[0])
-        {
-            bdrv_refresh_filename(bs->file->bs);
-            error_setg(errp, "Cannot use relative extent paths with VMDK "
-                       "descriptor file '%s'", bs->file->bs->filename);
-            return -EINVAL;
-        }
+        if (path_is_absolute(fname)) {
+            extent_path = g_strdup(fname);
+        } else {
+            if (!desc_file_dir) {
+                desc_file_dir = bdrv_dirname(bs->file->bs, errp);
+                if (!desc_file_dir) {
+                    bdrv_refresh_filename(bs->file->bs);
+                    error_prepend(errp, "Cannot use relative paths with VMDK "
+                                  "descriptor file '%s': ",
+                                  bs->file->bs->filename);
+                    ret = -EINVAL;
+                    goto out;
+                }
+            }
 
-        extent_path = path_combine(desc_file_path, fname);
+            extent_path = g_strconcat(desc_file_dir, fname, NULL);
+        }
 
         ret = snprintf(extent_opt_prefix, 32, "extents.%d", s->num_extents);
         assert(ret < 32);
@@ -1149,7 +1156,8 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
         g_free(extent_path);
         if (local_err) {
             error_propagate(errp, local_err);
-            return -EINVAL;
+            ret = -EINVAL;
+            goto out;
         }
 
         /* save to extents array */
@@ -1160,7 +1168,7 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
                             0, 0, 0, 0, 0, &extent, errp);
             if (ret < 0) {
                 bdrv_unref_child(bs, extent_file);
-                return ret;
+                goto out;
             }
             extent->flat_start_offset = flat_offset << 9;
         } else if (!strcmp(type, "SPARSE") || !strcmp(type, "VMFSSPARSE")) {
@@ -1175,24 +1183,27 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
             g_free(buf);
             if (ret) {
                 bdrv_unref_child(bs, extent_file);
-                return ret;
+                goto out;
             }
             extent = &s->extents[s->num_extents - 1];
         } else if (!strcmp(type, "SESPARSE")) {
             ret = vmdk_open_se_sparse(bs, extent_file, bs->open_flags, errp);
             if (ret) {
                 bdrv_unref_child(bs, extent_file);
-                return ret;
+                goto out;
             }
             extent = &s->extents[s->num_extents - 1];
         } else {
             error_setg(errp, "Unsupported extent type '%s'", type);
             bdrv_unref_child(bs, extent_file);
-            return -ENOTSUP;
+            ret = -ENOTSUP;
+            goto out;
         }
         extent->type = g_strdup(type);
     }
-    return 0;
+
+    ret = 0;
+    goto out;
 
 invalid:
     np = next_line(p);
@@ -1201,7 +1212,11 @@ invalid:
         np--;
     }
     error_setg(errp, "Invalid extent line: %.*s", (int)(np - p), p);
-    return -EINVAL;
+    ret = -EINVAL;
+
+out:
+    g_free(desc_file_dir);
+    return ret;
 }
 
 static int vmdk_open_desc_file(BlockDriverState *bs, int flags, char *buf,
@@ -1228,8 +1243,7 @@ static int vmdk_open_desc_file(BlockDriverState *bs, int flags, char *buf,
     }
     s->create_type = g_strdup(ct);
     s->desc_offset = 0;
-    ret = vmdk_parse_extents(buf, bs, bs->file->bs->exact_filename, options,
-                             errp);
+    ret = vmdk_parse_extents(buf, bs, options, errp);
 exit:
     return ret;
 }
@@ -1720,6 +1734,16 @@ static int vmdk_write_extent(VmdkExtent *extent, int64_t cluster_offset,
     if (extent->compressed) {
         void *compressed_data;
 
+        /* Only whole clusters */
+        if (offset_in_cluster ||
+            n_bytes > (extent->cluster_sectors * SECTOR_SIZE) ||
+            (n_bytes < (extent->cluster_sectors * SECTOR_SIZE) &&
+             offset + n_bytes != extent->end_sector * SECTOR_SIZE))
+        {
+            ret = -EINVAL;
+            goto out;
+        }
+
         if (!extent->has_marker) {
             ret = -EINVAL;
             goto out;
diff --git a/qemu-io-cmds.c b/qemu-io-cmds.c
index 8904733961..d46fa166d3 100644
--- a/qemu-io-cmds.c
+++ b/qemu-io-cmds.c
@@ -350,6 +350,79 @@ static void qemu_io_free(void *p)
     qemu_vfree(p);
 }
 
+/*
+ * qemu_io_alloc_from_file()
+ *
+ * Allocates the buffer and populates it with the content of the given file
+ * up to @len bytes. If the file length is less than @len, then the buffer
+ * is populated with the file content cyclically.
+ *
+ * @blk - the block backend where the buffer content is going to be written to
+ * @len - the buffer length
+ * @file_name - the file to read the content from
+ *
+ * Returns: the buffer pointer on success
+ *          NULL on error
+ */
+static void *qemu_io_alloc_from_file(BlockBackend *blk, size_t len,
+                                     const char *file_name)
+{
+    char *buf, *buf_origin;
+    FILE *f = fopen(file_name, "r");
+    int pattern_len;
+
+    if (!f) {
+        perror(file_name);
+        return NULL;
+    }
+
+    if (qemuio_misalign) {
+        len += MISALIGN_OFFSET;
+    }
+
+    buf_origin = buf = blk_blockalign(blk, len);
+
+    if (qemuio_misalign) {
+        buf_origin += MISALIGN_OFFSET;
+        buf += MISALIGN_OFFSET;
+        len -= MISALIGN_OFFSET;
+    }
+
+    pattern_len = fread(buf_origin, 1, len, f);
+
+    if (ferror(f)) {
+        perror(file_name);
+        goto error;
+    }
+
+    if (pattern_len == 0) {
+        fprintf(stderr, "%s: file is empty\n", file_name);
+        goto error;
+    }
+
+    fclose(f);
+
+    if (len > pattern_len) {
+        len -= pattern_len;
+        buf += pattern_len;
+
+        while (len > 0) {
+            size_t len_to_copy = MIN(pattern_len, len);
+
+            memcpy(buf, buf_origin, len_to_copy);
+
+            len -= len_to_copy;
+            buf += len_to_copy;
+        }
+    }
+
+    return buf_origin;
+
+error:
+    qemu_io_free(buf_origin);
+    return NULL;
+}
+
 static void dump_buffer(const void *buffer, int64_t offset, int64_t len)
 {
     uint64_t i;
@@ -948,6 +1021,7 @@ static void write_help(void)
 " -n, -- with -z, don't allow slow fallback\n"
 " -p, -- ignored for backwards compatibility\n"
 " -P, -- use different pattern to fill file\n"
+" -s, -- use a pattern file to fill the write buffer\n"
 " -C, -- report statistics in a machine parsable format\n"
 " -q, -- quiet mode, do not show I/O statistics\n"
 " -u, -- with -z, allow unmapping\n"
@@ -964,7 +1038,7 @@ static const cmdinfo_t write_cmd = {
     .perm       = BLK_PERM_WRITE,
     .argmin     = 2,
     .argmax     = -1,
-    .args       = "[-bcCfnquz] [-P pattern] off len",
+    .args       = "[-bcCfnquz] [-P pattern | -s source_file] off len",
     .oneline    = "writes a number of bytes at a specified offset",
     .help       = write_help,
 };
@@ -973,7 +1047,7 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
 {
     struct timespec t1, t2;
     bool Cflag = false, qflag = false, bflag = false;
-    bool Pflag = false, zflag = false, cflag = false;
+    bool Pflag = false, zflag = false, cflag = false, sflag = false;
     int flags = 0;
     int c, cnt, ret;
     char *buf = NULL;
@@ -982,8 +1056,9 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
     /* Some compilers get confused and warn if this is not initialized.  */
     int64_t total = 0;
     int pattern = 0xcd;
+    const char *file_name = NULL;
 
-    while ((c = getopt(argc, argv, "bcCfnpP:quz")) != -1) {
+    while ((c = getopt(argc, argv, "bcCfnpP:qs:uz")) != -1) {
         switch (c) {
         case 'b':
             bflag = true;
@@ -1013,6 +1088,10 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
         case 'q':
             qflag = true;
             break;
+        case 's':
+            sflag = true;
+            file_name = optarg;
+            break;
         case 'u':
             flags |= BDRV_REQ_MAY_UNMAP;
             break;
@@ -1050,8 +1129,9 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
         return -EINVAL;
     }
 
-    if (zflag && Pflag) {
-        printf("-z and -P cannot be specified at the same time\n");
+    if (zflag + Pflag + sflag > 1) {
+        printf("Only one of -z, -P, and -s "
+               "can be specified at the same time\n");
         return -EINVAL;
     }
 
@@ -1087,7 +1167,14 @@ static int write_f(BlockBackend *blk, int argc, char **argv)
     }
 
     if (!zflag) {
-        buf = qemu_io_alloc(blk, count, pattern);
+        if (sflag) {
+            buf = qemu_io_alloc_from_file(blk, count, file_name);
+            if (!buf) {
+                return -EINVAL;
+            }
+        } else {
+            buf = qemu_io_alloc(blk, count, pattern);
+        }
     }
 
     clock_gettime(CLOCK_MONOTONIC, &t1);
diff --git a/tests/check-block.sh b/tests/check-block.sh
index c8b6cec3f6..679aedec50 100755
--- a/tests/check-block.sh
+++ b/tests/check-block.sh
@@ -21,6 +21,11 @@ if grep -q "TARGET_GPROF=y" *-softmmu/config-target.mak 2>/dev/null ; then
     exit 0
 fi
 
+if grep -q "CFLAGS.*-fsanitize" config-host.mak 2>/dev/null ; then
+    echo "Sanitizers are enabled ==> Not running the qemu-iotests."
+    exit 0
+fi
+
 if [ -z "$(find . -name 'qemu-system-*' -print)" ]; then
     echo "No qemu-system binary available ==> Not running the qemu-iotests."
     exit 0
diff --git a/tests/qemu-iotests/002 b/tests/qemu-iotests/002
index fd413bce48..1a0d411df5 100755
--- a/tests/qemu-iotests/002
+++ b/tests/qemu-iotests/002
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=128M
diff --git a/tests/qemu-iotests/003 b/tests/qemu-iotests/003
index ccd3a39dfb..33eeade0de 100755
--- a/tests/qemu-iotests/003
+++ b/tests/qemu-iotests/003
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 size=128M
 offset=67M
diff --git a/tests/qemu-iotests/005 b/tests/qemu-iotests/005
index 9c7681c19b..58442762fe 100755
--- a/tests/qemu-iotests/005
+++ b/tests/qemu-iotests/005
@@ -43,7 +43,8 @@ _supported_fmt generic
 _supported_proto generic
 _supported_os Linux
 _unsupported_imgopts "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 # vpc is limited to 127GB, so we can't test it here
 if [ "$IMGFMT" = "vpc" ]; then
diff --git a/tests/qemu-iotests/009 b/tests/qemu-iotests/009
index 51b200db1d..4dc7d210f9 100755
--- a/tests/qemu-iotests/009
+++ b/tests/qemu-iotests/009
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=6G
diff --git a/tests/qemu-iotests/010 b/tests/qemu-iotests/010
index 48c533f632..df809b3088 100755
--- a/tests/qemu-iotests/010
+++ b/tests/qemu-iotests/010
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=6G
diff --git a/tests/qemu-iotests/011 b/tests/qemu-iotests/011
index 56f704b5b9..57b99ae4a9 100755
--- a/tests/qemu-iotests/011
+++ b/tests/qemu-iotests/011
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=6G
diff --git a/tests/qemu-iotests/017 b/tests/qemu-iotests/017
index 79875de454..0a4b854e65 100755
--- a/tests/qemu-iotests/017
+++ b/tests/qemu-iotests/017
@@ -41,7 +41,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow qcow2 vmdk qed
 _supported_proto generic
 _unsupported_proto vxhs
-_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat"
+_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat" \
+                     "subformat=streamOptimized"
 
 TEST_OFFSETS="0 4294967296"
 
diff --git a/tests/qemu-iotests/018 b/tests/qemu-iotests/018
index 78169838ba..c69ce09209 100755
--- a/tests/qemu-iotests/018
+++ b/tests/qemu-iotests/018
@@ -41,7 +41,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow qcow2 vmdk qed
 _supported_proto file
 _supported_os Linux
-_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat"
+_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat" \
+                     "streamOptimized"
 
 TEST_OFFSETS="0 4294967296"
 
diff --git a/tests/qemu-iotests/019 b/tests/qemu-iotests/019
index a56dd30bed..b4f5234609 100755
--- a/tests/qemu-iotests/019
+++ b/tests/qemu-iotests/019
@@ -47,7 +47,8 @@ _supported_proto file
 _supported_os Linux
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 TEST_OFFSETS="0 4294967296"
 CLUSTER_SIZE=65536
diff --git a/tests/qemu-iotests/020 b/tests/qemu-iotests/020
index 6b0ebb37d2..f41b92f35f 100755
--- a/tests/qemu-iotests/020
+++ b/tests/qemu-iotests/020
@@ -44,7 +44,8 @@ _supported_fmt qcow qcow2 vmdk qed
 _supported_proto file
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 TEST_OFFSETS="0 4294967296"
 
diff --git a/tests/qemu-iotests/026 b/tests/qemu-iotests/026
index e30243608b..ffb18ab6b5 100755
--- a/tests/qemu-iotests/026
+++ b/tests/qemu-iotests/026
@@ -41,8 +41,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # Currently only qcow2 supports rebasing
 _supported_fmt qcow2
 _supported_proto file
-_default_cache_mode "writethrough"
-_supported_cache_modes "writethrough" "none"
+_default_cache_mode writethrough
+_supported_cache_modes writethrough none
 # The refcount table tests expect a certain minimum width for refcount entries
 # (so that the refcount table actually needs to grow); that minimum is 16 bits,
 # being the default refcount entry width.
diff --git a/tests/qemu-iotests/027 b/tests/qemu-iotests/027
index 4cb638022a..494be0921f 100755
--- a/tests/qemu-iotests/027
+++ b/tests/qemu-iotests/027
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt vmdk qcow qcow2 qed
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=128M
diff --git a/tests/qemu-iotests/032 b/tests/qemu-iotests/032
index 988a8c5d8f..8337a4d825 100755
--- a/tests/qemu-iotests/032
+++ b/tests/qemu-iotests/032
@@ -42,6 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # This works for any image format (though unlikely to segfault for raw)
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 echo
 echo === Prepare image ===
diff --git a/tests/qemu-iotests/033 b/tests/qemu-iotests/033
index 362a48c0a0..8b40991d55 100755
--- a/tests/qemu-iotests/033
+++ b/tests/qemu-iotests/033
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt generic
 _supported_proto generic
+_unsupported_imgopts "subformat=streamOptimized"
 
 
 size=128M
diff --git a/tests/qemu-iotests/034 b/tests/qemu-iotests/034
index 324bed28c6..da4cea1571 100755
--- a/tests/qemu-iotests/034
+++ b/tests/qemu-iotests/034
@@ -41,7 +41,8 @@ _supported_proto file
 _supported_os Linux
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 CLUSTER_SIZE=4k
 size=128M
diff --git a/tests/qemu-iotests/037 b/tests/qemu-iotests/037
index 4946b9be92..e6517acbd4 100755
--- a/tests/qemu-iotests/037
+++ b/tests/qemu-iotests/037
@@ -40,7 +40,8 @@ _supported_fmt qcow qcow2 vmdk qed
 _supported_proto file
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 CLUSTER_SIZE=4k
 size=128M
diff --git a/tests/qemu-iotests/039 b/tests/qemu-iotests/039
index 0d4e963bd4..7c730d94a7 100755
--- a/tests/qemu-iotests/039
+++ b/tests/qemu-iotests/039
@@ -42,8 +42,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow2
 _supported_proto file
 _supported_os Linux
-_default_cache_mode "writethrough"
-_supported_cache_modes "writethrough"
+_default_cache_mode writethrough
+_supported_cache_modes writethrough
 
 size=128M
 
diff --git a/tests/qemu-iotests/052 b/tests/qemu-iotests/052
index 6e2ecbfe21..45a140910d 100755
--- a/tests/qemu-iotests/052
+++ b/tests/qemu-iotests/052
@@ -40,7 +40,7 @@ _supported_fmt generic
 _supported_proto file
 
 # Don't do O_DIRECT on tmpfs
-_supported_cache_modes "writeback" "writethrough" "unsafe"
+_supported_cache_modes writeback writethrough unsafe
 
 size=128M
 _make_test_img $size
diff --git a/tests/qemu-iotests/059 b/tests/qemu-iotests/059
index 279aee6815..10bfbaecec 100755
--- a/tests/qemu-iotests/059
+++ b/tests/qemu-iotests/059
@@ -114,11 +114,41 @@ $QEMU_IMG convert -f qcow2 -O vmdk -o subformat=streamOptimized "$TEST_IMG.qcow2
 
 echo
 echo "=== Testing monolithicFlat with internally generated JSON file name ==="
+
+echo '--- blkdebug ---'
+# Should work, because bdrv_dirname() works fine with blkdebug
 IMGOPTS="subformat=monolithicFlat" _make_test_img 64M
-$QEMU_IO -c "open -o driver=$IMGFMT,file.driver=blkdebug,file.image.filename=$TEST_IMG,file.inject-error.0.event=read_aio" 2>&1 \
-    | _filter_testdir | _filter_imgfmt
+$QEMU_IO -c "open -o driver=$IMGFMT,file.driver=blkdebug,file.image.filename=$TEST_IMG,file.inject-error.0.event=read_aio" \
+         -c info \
+    2>&1 \
+    | _filter_testdir | _filter_imgfmt | _filter_img_info
 _cleanup_test_img
 
+echo '--- quorum ---'
+# Should not work, because bdrv_dirname() does not work with quorum
+IMGOPTS="subformat=monolithicFlat" _make_test_img 64M
+cp "$TEST_IMG" "$TEST_IMG.orig"
+
+filename="json:{
+    \"driver\": \"$IMGFMT\",
+    \"file\": {
+        \"driver\": \"quorum\",
+        \"children\": [ {
+            \"driver\": \"file\",
+            \"filename\": \"$TEST_IMG\"
+        }, {
+            \"driver\": \"file\",
+            \"filename\": \"$TEST_IMG.orig\"
+        } ],
+        \"vote-threshold\": 1
+    } }"
+
+filename=$(echo "$filename" | tr '\n' ' ' | sed -e 's/\s\+/ /g')
+$QEMU_IMG info "$filename" 2>&1 \
+    | sed -e "s/'json:[^']*'/\$QUORUM_FILE/g" \
+    | _filter_testdir | _filter_imgfmt | _filter_img_info
+
+
 echo
 echo "=== Testing version 3 ==="
 _use_sample_img iotest-version3.vmdk.bz2
diff --git a/tests/qemu-iotests/059.out b/tests/qemu-iotests/059.out
index 4fab42a28c..39bf7e211d 100644
--- a/tests/qemu-iotests/059.out
+++ b/tests/qemu-iotests/059.out
@@ -13,21 +13,21 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 qemu-io: can't open device TEST_DIR/t.vmdk: L1 size too big
 
 === Testing monolithicFlat creation and opening ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648 subformat=monolithicFlat
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 2 GiB (2147483648 bytes)
 
 === Testing monolithicFlat with zeroed_grain ===
 qemu-img: TEST_DIR/t.IMGFMT: Flat image can't enable zeroed grain
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648 subformat=monolithicFlat
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2147483648
 
 === Testing big twoGbMaxExtentFlat ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824000 subformat=twoGbMaxExtentFlat
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1073741824000
 image: TEST_DIR/t.vmdk
 file format: vmdk
 virtual size: 0.977 TiB (1073741824000 bytes)
-disk size: 16 KiB
+disk size: 1.97 MiB
 Format specific information:
     cid: XXXXXXXX
     parent cid: XXXXXXXX
@@ -2038,7 +2038,7 @@ Format specific information:
 qemu-img: Could not open 'TEST_DIR/t.IMGFMT': Invalid extent line: RW 12582912 VMFS "dummy.IMGFMT" 1
 
 === Testing truncated sparse ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=107374182400 subformat=monolithicSparse
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=107374182400
 qemu-img: Could not open 'TEST_DIR/t.IMGFMT': File truncated, expecting at least 13172736 bytes
 
 === Converting to streamOptimized from image with small cluster size===
@@ -2049,8 +2049,14 @@ wrote 512/512 bytes at offset 10240
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
 === Testing monolithicFlat with internally generated JSON file name ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 subformat=monolithicFlat
-qemu-io: can't open: Cannot use relative extent paths with VMDK descriptor file 'json:{"image": {"driver": "file", "filename": "TEST_DIR/t.IMGFMT"}, "driver": "blkdebug", "inject-error.0.event": "read_aio"}'
+--- blkdebug ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+format name: IMGFMT
+cluster size: 0 bytes
+vm state offset: 0 bytes
+--- quorum ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+qemu-img: Could not open $QUORUM_FILE: Cannot use relative paths with VMDK descriptor file $QUORUM_FILE: Cannot generate a base directory for quorum nodes
 
 === Testing version 3 ===
 image: TEST_DIR/iotest-version3.IMGFMT
@@ -2259,7 +2265,7 @@ read 512/512 bytes at offset 64931328
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
 === Testing 4TB monolithicFlat creation and IO ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=4398046511104 subformat=monolithicFlat
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=4398046511104
 image: TEST_DIR/t.IMGFMT
 file format: IMGFMT
 virtual size: 4 TiB (4398046511104 bytes)
@@ -2333,7 +2339,7 @@ read 1024/1024 bytes at offset 966367641600
 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
 === Testing qemu-img map on extents ===
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=33285996544 subformat=monolithicSparse
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=33285996544
 wrote 1024/1024 bytes at offset 65024
 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 wrote 1024/1024 bytes at offset 2147483136
@@ -2344,7 +2350,7 @@ Offset          Length          Mapped to       File
 0               0x20000         0x3f0000        TEST_DIR/t.vmdk
 0x7fff0000      0x20000         0x410000        TEST_DIR/t.vmdk
 0x140000000     0x10000         0x430000        TEST_DIR/t.vmdk
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=33285996544 subformat=twoGbMaxExtentSparse
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=33285996544
 wrote 1024/1024 bytes at offset 65024
 1 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 wrote 1024/1024 bytes at offset 2147483136
diff --git a/tests/qemu-iotests/063 b/tests/qemu-iotests/063
index fe4892e467..7cf0427af4 100755
--- a/tests/qemu-iotests/063
+++ b/tests/qemu-iotests/063
@@ -43,7 +43,8 @@ _supported_fmt qcow qcow2 vmdk qed raw
 _supported_proto file
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 _make_test_img 4M
 
diff --git a/tests/qemu-iotests/071 b/tests/qemu-iotests/071
index 1cca9233d0..fab526666b 100755
--- a/tests/qemu-iotests/071
+++ b/tests/qemu-iotests/071
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt qcow2
 _supported_proto file
+_require_drivers blkdebug blkverify
 
 do_run_qemu()
 {
diff --git a/tests/qemu-iotests/072 b/tests/qemu-iotests/072
index 661b36da2d..f0b73e7e65 100755
--- a/tests/qemu-iotests/072
+++ b/tests/qemu-iotests/072
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt vpc vmdk vhdx vdi qed qcow2 qcow
 _supported_proto file
+_unsupported_imgopts "subformat=streamOptimized"
 
 IMG_SIZE=64M
 
diff --git a/tests/qemu-iotests/081 b/tests/qemu-iotests/081
index c418bab093..85acdf76d4 100755
--- a/tests/qemu-iotests/081
+++ b/tests/qemu-iotests/081
@@ -41,6 +41,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt raw
 _supported_proto file
 _supported_os Linux
+_require_drivers quorum
 
 do_run_qemu()
 {
@@ -55,9 +56,6 @@ run_qemu()
                           | _filter_qemu_io | _filter_generated_node_ids
 }
 
-test_quorum=$($QEMU_IMG --help|grep quorum)
-[ "$test_quorum" = "" ] && _supported_fmt quorum
-
 quorum="driver=raw,file.driver=quorum,file.vote-threshold=2"
 quorum="$quorum,file.children.0.file.filename=$TEST_DIR/1.raw"
 quorum="$quorum,file.children.1.file.filename=$TEST_DIR/2.raw"
diff --git a/tests/qemu-iotests/091 b/tests/qemu-iotests/091
index d62ef18a02..f4b44659ae 100755
--- a/tests/qemu-iotests/091
+++ b/tests/qemu-iotests/091
@@ -46,8 +46,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow2
 _supported_proto file
 _supported_os Linux
-_default_cache_mode "none"
-_supported_cache_modes "writethrough" "none" "writeback"
+_default_cache_mode none
+_supported_cache_modes writethrough none writeback
 
 size=1G
 
diff --git a/tests/qemu-iotests/099 b/tests/qemu-iotests/099
index ae02f27afe..c3cf66798a 100755
--- a/tests/qemu-iotests/099
+++ b/tests/qemu-iotests/099
@@ -42,6 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow qcow2 qed vdi vhdx vmdk vpc
 _supported_proto file
 _supported_os Linux
+_require_drivers blkdebug blkverify
 _unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat" \
     "subformat=twoGbMaxExtentSparse"
 
diff --git a/tests/qemu-iotests/105 b/tests/qemu-iotests/105
index 3346e8cb25..4d55a2d3ef 100755
--- a/tests/qemu-iotests/105
+++ b/tests/qemu-iotests/105
@@ -39,7 +39,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow2 vmdk vhdx qed
 _supported_proto generic
 _unsupported_imgopts "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+                     "subformat=twoGbMaxExtentSparse" \
+                     "subformat=streamOptimized"
 
 echo
 echo "creating large image"
diff --git a/tests/qemu-iotests/110 b/tests/qemu-iotests/110
index 2cdc7c8a72..2ef516baf1 100755
--- a/tests/qemu-iotests/110
+++ b/tests/qemu-iotests/110
@@ -40,7 +40,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # Any format supporting backing files
 _supported_fmt qed qcow qcow2 vmdk
 _supported_proto file
-_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat"
+_unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat" \
+                     "subformat=twoGbMaxExtentSparse"
 
 TEST_IMG_REL=$(basename "$TEST_IMG")
 
diff --git a/tests/qemu-iotests/120 b/tests/qemu-iotests/120
index e9b4fbb009..2931a7550f 100755
--- a/tests/qemu-iotests/120
+++ b/tests/qemu-iotests/120
@@ -40,6 +40,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt generic
 _supported_proto file
 _unsupported_fmt luks
+_require_drivers raw
 
 _make_test_img 64M
 
diff --git a/tests/qemu-iotests/126 b/tests/qemu-iotests/126
index 9b0dcf9255..b7fce1e59d 100755
--- a/tests/qemu-iotests/126
+++ b/tests/qemu-iotests/126
@@ -33,6 +33,8 @@ status=1	# failure is the default!
 
 # Needs backing file support
 _supported_fmt qcow qcow2 qed vmdk
+_unsupported_imgopts "subformat=monolithicFlat" \
+                     "subformat=twoGbMaxExtentFlat"
 # This is the default protocol (and we want to test the difference between
 # colons which separate a protocol prefix from the rest and colons which are
 # just part of the filename, so we cannot test protocols which require a prefix)
diff --git a/tests/qemu-iotests/150.out b/tests/qemu-iotests/150.out.qcow2
similarity index 100%
rename from tests/qemu-iotests/150.out
rename to tests/qemu-iotests/150.out.qcow2
diff --git a/tests/qemu-iotests/150.out.raw b/tests/qemu-iotests/150.out.raw
new file mode 100644
index 0000000000..3cdc7727a5
--- /dev/null
+++ b/tests/qemu-iotests/150.out.raw
@@ -0,0 +1,12 @@
+QA output created by 150
+
+=== Mapping sparse conversion ===
+
+Offset          Length          File
+0               0x1000          TEST_DIR/t.IMGFMT
+
+=== Mapping non-sparse conversion ===
+
+Offset          Length          File
+0               0x100000        TEST_DIR/t.IMGFMT
+*** done
diff --git a/tests/qemu-iotests/162 b/tests/qemu-iotests/162
index 4e5ed74fd5..2d719afbed 100755
--- a/tests/qemu-iotests/162
+++ b/tests/qemu-iotests/162
@@ -39,9 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt generic
-
-test_ssh=$($QEMU_IMG --help | grep '^Supported formats:.* ssh\( \|$\)')
-[ "$test_ssh" = "" ] && _notrun "ssh support required"
+_require_drivers ssh
 
 echo
 echo '=== NBD ==='
diff --git a/tests/qemu-iotests/175 b/tests/qemu-iotests/175
index 51e62c8276..55db2803ed 100755
--- a/tests/qemu-iotests/175
+++ b/tests/qemu-iotests/175
@@ -37,14 +37,33 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # the file size.  This function hides the resulting difference in the
 # stat -c '%b' output.
 # Parameter 1: Number of blocks an empty file occupies
-# Parameter 2: Image size in bytes
+# Parameter 2: Minimal number of blocks in an image
+# Parameter 3: Image size in bytes
 _filter_blocks()
 {
     extra_blocks=$1
-    img_size=$2
+    min_blocks=$2
+    img_size=$3
 
-    sed -e "s/blocks=$extra_blocks\\(\$\\|[^0-9]\\)/nothing allocated/" \
-        -e "s/blocks=$((extra_blocks + img_size / 512))\\(\$\\|[^0-9]\\)/everything allocated/"
+    sed -e "s/blocks=$min_blocks\\(\$\\|[^0-9]\\)/min allocation/" \
+        -e "s/blocks=$((extra_blocks + img_size / 512))\\(\$\\|[^0-9]\\)/max allocation/"
+}
+
+# Resize image using block_resize.
+# Parameter 1: image path
+# Parameter 2: new size
+_block_resize()
+{
+    local path=$1
+    local size=$2
+
+    $QEMU -qmp stdio -nographic -nodefaults \
+        -blockdev file,node-name=file,filename=$path,cache.direct=on \
+        <<EOF
+{'execute': 'qmp_capabilities'}
+{'execute': 'block_resize', 'arguments': {'node-name': 'file', 'size': $size}}
+{'execute': 'quit'}
+EOF
 }
 
 # get standard environment, filters and checks
@@ -55,21 +74,37 @@ _supported_fmt raw
 _supported_proto file
 _supported_os Linux
 
+_default_cache_mode none
+_supported_cache_modes none directsync
+
 size=$((1 * 1024 * 1024))
 
 touch "$TEST_DIR/empty"
 extra_blocks=$(stat -c '%b' "$TEST_DIR/empty")
 
+# We always write the first byte; check how many blocks this filesystem
+# allocates to match empty image alloation.
+printf "\0" > "$TEST_DIR/empty"
+min_blocks=$(stat -c '%b' "$TEST_DIR/empty")
+
 echo
 echo "== creating image with default preallocation =="
 _make_test_img $size | _filter_imgfmt
-stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $size
+stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
 
 for mode in off full falloc; do
     echo
     echo "== creating image with preallocation $mode =="
     IMGOPTS=preallocation=$mode _make_test_img $size | _filter_imgfmt
-    stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $size
+    stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
+done
+
+for new_size in 4096 1048576; do
+    echo
+    echo "== resize empty image with block_resize =="
+    _make_test_img 0 | _filter_imgfmt
+    _block_resize $TEST_IMG $new_size >/dev/null
+    stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $new_size
 done
 
 # success, all done
diff --git a/tests/qemu-iotests/175.out b/tests/qemu-iotests/175.out
index 6d9a5ed84e..39c2ee0f62 100644
--- a/tests/qemu-iotests/175.out
+++ b/tests/qemu-iotests/175.out
@@ -2,17 +2,25 @@ QA output created by 175
 
 == creating image with default preallocation ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576
-size=1048576, nothing allocated
+size=1048576, min allocation
 
 == creating image with preallocation off ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=off
-size=1048576, nothing allocated
+size=1048576, min allocation
 
 == creating image with preallocation full ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=full
-size=1048576, everything allocated
+size=1048576, max allocation
 
 == creating image with preallocation falloc ==
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 preallocation=falloc
-size=1048576, everything allocated
+size=1048576, max allocation
+
+== resize empty image with block_resize ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=0
+size=4096, min allocation
+
+== resize empty image with block_resize ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=0
+size=1048576, min allocation
  *** done
diff --git a/tests/qemu-iotests/178.out.qcow2 b/tests/qemu-iotests/178.out.qcow2
index 55a8dc926f..9e7d8c44df 100644
--- a/tests/qemu-iotests/178.out.qcow2
+++ b/tests/qemu-iotests/178.out.qcow2
@@ -101,7 +101,7 @@ converted image file size in bytes: 196608
 == raw input image with data (human) ==
 
 Formatting 'TEST_DIR/t.qcow2', fmt=IMGFMT size=1073741824
-required size: 393216
+required size: 458752
 fully allocated size: 1074135040
 wrote 512/512 bytes at offset 512
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
@@ -257,7 +257,7 @@ converted image file size in bytes: 196608
 
 Formatting 'TEST_DIR/t.qcow2', fmt=IMGFMT size=1073741824
 {
-    "required": 393216,
+    "required": 458752,
     "fully-allocated": 1074135040
 }
 wrote 512/512 bytes at offset 512
diff --git a/tests/qemu-iotests/184 b/tests/qemu-iotests/184
index cb0c181228..33dd8d2a4f 100755
--- a/tests/qemu-iotests/184
+++ b/tests/qemu-iotests/184
@@ -33,6 +33,7 @@ trap "exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_os Linux
+_require_drivers throttle
 
 do_run_qemu()
 {
diff --git a/tests/qemu-iotests/186 b/tests/qemu-iotests/186
index 5f6b18c150..3ea0442d44 100755
--- a/tests/qemu-iotests/186
+++ b/tests/qemu-iotests/186
@@ -38,6 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_fmt qcow2
 _supported_proto file
+_require_drivers null-co
 
 if [ "$QEMU_DEFAULT_MACHINE" != "pc" ]; then
     _notrun "Requires a PC machine"
diff --git a/tests/qemu-iotests/197 b/tests/qemu-iotests/197
index 383d7d7f61..1d4f6786db 100755
--- a/tests/qemu-iotests/197
+++ b/tests/qemu-iotests/197
@@ -53,6 +53,7 @@ _supported_fmt generic
 _supported_proto generic
 # LUKS support may be possible, but it complicates things.
 _unsupported_fmt luks
+_unsupported_imgopts "subformat=streamOptimized"
 
 echo
 echo '=== Copy-on-read ==='
diff --git a/tests/qemu-iotests/215 b/tests/qemu-iotests/215
index 958c14f5a0..2eb377d682 100755
--- a/tests/qemu-iotests/215
+++ b/tests/qemu-iotests/215
@@ -50,6 +50,7 @@ _supported_fmt generic
 _supported_proto generic
 # LUKS support may be possible, but it complicates things.
 _unsupported_fmt luks
+_unsupported_imgopts "subformat=streamOptimized"
 
 echo
 echo '=== Copy-on-read ==='
diff --git a/tests/qemu-iotests/221.out b/tests/qemu-iotests/221.out
index 9f9dd52bb0..dca024a0c3 100644
--- a/tests/qemu-iotests/221.out
+++ b/tests/qemu-iotests/221.out
@@ -3,14 +3,18 @@ QA output created by 221
 === Check mapping of unaligned raw image ===
 
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=65537
-[{ "start": 0, "length": 66048, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 66048, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61952, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61952, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
 wrote 1/1 bytes at offset 65536
 1 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-[{ "start": 0, "length": 65536, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61440, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
 { "start": 65536, "length": 1, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
 { "start": 65537, "length": 511, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 65536, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 61440, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
 { "start": 65536, "length": 1, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
 { "start": 65537, "length": 511, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
 *** done
diff --git a/tests/qemu-iotests/251 b/tests/qemu-iotests/251
index 13f85de9cd..7918ba3559 100755
--- a/tests/qemu-iotests/251
+++ b/tests/qemu-iotests/251
@@ -40,6 +40,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt generic
 _supported_proto file
 _supported_os Linux
+_unsupported_imgopts "subformat=streamOptimized"
 
 if [ "$IMGOPTSSYNTAX" = "true" ]; then
     # We use json:{} filenames here, so we cannot work with additional options.
diff --git a/tests/qemu-iotests/253.out b/tests/qemu-iotests/253.out
index 607c0baa0b..3d08b305d7 100644
--- a/tests/qemu-iotests/253.out
+++ b/tests/qemu-iotests/253.out
@@ -3,12 +3,16 @@ QA output created by 253
 === Check mapping of unaligned raw image ===
 
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048575
-[{ "start": 0, "length": 1048576, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
-[{ "start": 0, "length": 1048576, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 1044480, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 1044480, "depth": 0, "zero": true, "data": false, "offset": OFFSET}]
 wrote 65535/65535 bytes at offset 983040
 63.999 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-[{ "start": 0, "length": 983040, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 978944, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
 { "start": 983040, "length": 65536, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
-[{ "start": 0, "length": 983040, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
+[{ "start": 0, "length": 4096, "depth": 0, "zero": false, "data": true, "offset": OFFSET},
+{ "start": 4096, "length": 978944, "depth": 0, "zero": true, "data": false, "offset": OFFSET},
 { "start": 983040, "length": 65536, "depth": 0, "zero": false, "data": true, "offset": OFFSET}]
 *** done
diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index c24874ff4a..a58232eefb 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -581,13 +581,13 @@ export QEMU_PROG="$(type -p "$QEMU_PROG")"
 
 case "$QEMU_PROG" in
     *qemu-system-arm|*qemu-system-aarch64)
-        export QEMU_OPTIONS="-nodefaults -machine virt,accel=qtest"
+        export QEMU_OPTIONS="-nodefaults -display none -machine virt,accel=qtest"
         ;;
     *qemu-system-tricore)
-        export QEMU_OPTIONS="-nodefaults -machine tricore_testboard,accel=qtest"
+        export QEMU_OPTIONS="-nodefaults -display none -machine tricore_testboard,accel=qtest"
         ;;
     *)
-        export QEMU_OPTIONS="-nodefaults -machine accel=qtest"
+        export QEMU_OPTIONS="-nodefaults -display none -machine accel=qtest"
         ;;
 esac
 
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index 8e9235d6fe..445a1c23e0 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -130,8 +130,8 @@ _filter_img_create()
         -e "s# compat6=\\(on\\|off\\)##g" \
         -e "s# static=\\(on\\|off\\)##g" \
         -e "s# zeroed_grain=\\(on\\|off\\)##g" \
-        -e "s# subformat='[^']*'##g" \
-        -e "s# adapter_type='[^']*'##g" \
+        -e "s# subformat=[^ ]*##g" \
+        -e "s# adapter_type=[^ ]*##g" \
         -e "s# hwversion=[^ ]*##g" \
         -e "s# lazy_refcounts=\\(on\\|off\\)##g" \
         -e "s# block_size=[0-9]\\+##g" \
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 5502c3da2f..ee20be8920 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -520,5 +520,19 @@ _require_command()
     [ -x "$c" ] || _notrun "$1 utility required, skipped this test"
 }
 
+# Check that a set of drivers has been whitelisted in the QEMU binary
+#
+_require_drivers()
+{
+    available=$($QEMU -drive format=help | \
+                sed -e '/Supported formats:/!d' -e 's/Supported formats://')
+    for driver
+    do
+        if ! echo "$available" | grep -q " $driver\( \|$\)"; then
+            _notrun "$driver not available"
+        fi
+    done
+}
+
 # make sure this script returns success
 true