diff --git a/include/qemu/ratelimit.h b/include/qemu/ratelimit.h
index c6ac281..d1610f1 100644
--- a/include/qemu/ratelimit.h
+++ b/include/qemu/ratelimit.h
@@ -42,7 +42,7 @@ static inline void ratelimit_set_speed(RateLimit *limit, uint64_t speed,
                                        uint64_t slice_ns)
 {
     limit->slice_ns = slice_ns;
-    limit->slice_quota = ((double)speed * 1000000000ULL) / slice_ns;
+    limit->slice_quota = ((double)speed * slice_ns)/1000000000ULL;
 }
 
 #endif
diff --git a/tests/Makefile b/tests/Makefile
index ca680e5..284dc0c 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -18,6 +18,8 @@ check-unit-y += tests/test-iov$(EXESUF)
 
 check-block-$(CONFIG_POSIX) += tests/qemu-iotests-quick.sh
 
+check-backup-y = tests/backup-test$(EXESUF)
+
 # All QTests for now are POSIX-only, but the dependencies are
 # really in libqtest, not in the testcases themselves.
 check-qtest-i386-y = tests/fdc-test$(EXESUF)
@@ -50,6 +52,7 @@ tests/check-qfloat$(EXESUF): tests/check-qfloat.o qfloat.o
 tests/check-qjson$(EXESUF): tests/check-qjson.o $(qobject-obj-y) qemu-tool.o
 tests/test-coroutine$(EXESUF): tests/test-coroutine.o $(coroutine-obj-y) $(tools-obj-y) $(block-obj-y) iov.o libqemustub.a
 tests/test-iov$(EXESUF): tests/test-iov.o iov.o
+tests/backup-test$(EXESUF): tests/backup-test.o vma-reader.o $(tools-obj-y) $(block-obj-y) libqemustub.a
 
 tests/test-qapi-types.c tests/test-qapi-types.h :\
 $(SRC_PATH)/qapi-schema-test.json $(SRC_PATH)/scripts/qapi-types.py
@@ -142,10 +145,14 @@ check-tests/qemu-iotests-quick.sh: tests/qemu-iotests-quick.sh qemu-img$(EXESUF)
 
 # Consolidated targets
 
-.PHONY: check-qtest check-unit check
+.PHONY: check-backup check-qtest check-unit check
 check-qtest: $(patsubst %,check-qtest-%, $(QTEST_TARGETS))
 check-unit: $(patsubst %,check-%, $(check-unit-y))
 check-block: $(patsubst %,check-%, $(check-block-y))
-check: check-unit check-qtest
+
+check-backup: tests/backup-test$(EXESUF)
+	$<
+
+check: check-unit check-qtest check-backup
 
 -include $(wildcard tests/*.d)
diff --git a/tests/backup-test.c b/tests/backup-test.c
new file mode 100644
index 0000000..26ad346
--- /dev/null
+++ b/tests/backup-test.c
@@ -0,0 +1,505 @@
+/*
+ * QEMU backup test suit
+ *
+ * Copyright (C) Proxmox Server Solutions
+ *
+ * Authors:
+ *  Dietmar Maurer (dietmar@proxmox.com)
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ * Fixme: running 'backup-test -l' trigger a bug in g_slice_alloc()
+ * Note: 'G_SLICE=always-malloc ./tests/backup-test -l' works
+ *
+ */
+
+#include <sys/time.h>
+#include <sys/types.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <libgen.h>
+
+#include "qemu-common.h"
+#include "main-loop.h"
+#include "block_int.h"
+
+#include "vma.h"
+
+static int opt_debug;
+static int opt_loop;
+
+#define DPRINTF(fmt, ...) \
+    do { if (opt_debug) { printf(fmt, ## __VA_ARGS__); } } while (0)
+
+#define CLUSTER(x) (x*BACKUP_CLUSTER_SIZE)
+
+#define RUN_TEST(testfunc, speed) \
+    backup_test(#testfunc " speed " #speed, speed, testfunc);
+
+
+static unsigned char buf_sec_pattern_cd[BDRV_SECTOR_SIZE];
+static unsigned char buf_sec_pattern_32[BDRV_SECTOR_SIZE];
+
+#define TEST_IMG_SIZE (6*1024*1024+BDRV_SECTOR_SIZE)
+#define TEST_IMG_NAME "backuptest.raw"
+#define TEST_IMG_RESTORE_NAME "backuptest.raw.restore"
+#define TEST_VMA_NAME "backuptest.vma"
+
+typedef struct BackupCB {
+    VmaWriter *vmaw;
+    uint8_t dev_id;
+} BackupCB;
+
+static int backup_dump_cb(void *opaque, BlockDriverState *bs,
+                          int64_t cluster_num, unsigned char *buf)
+{
+    BackupCB *bcb = opaque;
+
+    DPRINTF("backup_dump_cb C%zd %d\n", cluster_num, bcb->dev_id);
+
+    if (vma_writer_write(bcb->vmaw, bcb->dev_id, cluster_num, buf) < 0) {
+        printf("backup_dump_cb vma_writer_write failed\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+static void backup_complete_cb(void *opaque, int ret)
+{
+    BackupCB *bcb = opaque;
+
+    DPRINTF("backup_complete_cb %d %d\n", bcb->dev_id, ret);
+
+    if (ret < 0) {
+        vma_writer_set_error(bcb->vmaw, "backup_complete_cb %d", ret);
+    }
+
+    if (vma_writer_close_stream(bcb->vmaw, bcb->dev_id) <= 0) {
+        if (vma_writer_close(bcb->vmaw) != 0) {
+            g_error("vma_writer_close failed");
+        }
+    }
+    DPRINTF("backup_complete_cb finish\n");
+}
+
+static void write_sec_pattern_cd(BlockDriverState *bs, int64_t offset)
+{
+    int ret;
+
+    DPRINTF("write_sec_pattern_cd %zd\n", offset);
+
+    if (offset & 0x1ff) {
+        g_error("write_sec_pattern_cd offset %zd is not sector aligned\n",
+                offset);
+    }
+
+    ret = bdrv_write(bs, offset >> 9, buf_sec_pattern_cd, 1);
+    if (ret < 0) {
+        g_error("write_sec_pattern_cd %zd failed", offset);
+    }
+
+}
+
+static void read_sec(BlockDriverState *bs, int64_t offset, unsigned char *buf)
+{
+    DPRINTF("read_sec C%zd start %zd\n", offset>>VMA_CLUSTER_BITS, offset);
+
+    if (offset & 0x1ff) {
+        g_error("read_sec offset %zd is not sector aligned\n", offset);
+    }
+
+    if (bdrv_read(bs, offset >> 9, buf, 1) < 0) {
+        g_error("bdrv_read failed");
+    }
+}
+
+static bool request_term;
+
+typedef struct TestCB {
+    Coroutine *co;
+    BlockDriverState *bs;
+    bool finished;
+} TestCB;
+
+static TestCB *enter_test_co(BlockDriverState *bs, CoroutineEntry *entry)
+{
+    TestCB *cb = g_new0(TestCB, 1);
+    cb->bs = bs;
+    cb->co = qemu_coroutine_create(entry);
+    qemu_coroutine_enter(cb->co, cb);
+    return cb;
+}
+
+static void test_co_sleep(double sec)
+{
+    co_sleep_ns(rt_clock, (int64_t)(sec*1000000000));
+};
+
+static void test_co_yield(void)
+{
+    co_sleep_ns(rt_clock, (int64_t)(1000));
+};
+
+static void coroutine_fn run_co_test1(void *opaque)
+{
+    assert(opaque);
+    TestCB *cb = (TestCB *)opaque;
+
+    test_co_sleep(0.2);
+    write_sec_pattern_cd(cb->bs, 5*BACKUP_CLUSTER_SIZE);
+    test_co_sleep(0.2);
+    write_sec_pattern_cd(cb->bs, 10*BACKUP_CLUSTER_SIZE);
+    test_co_sleep(0.2);
+    write_sec_pattern_cd(cb->bs, 10*BACKUP_CLUSTER_SIZE);
+
+    cb->finished = true;
+}
+
+static void coroutine_fn run_co_test2(void *opaque)
+{
+    assert(opaque);
+    TestCB *cb = (TestCB *)opaque;
+    unsigned char buf[512];
+
+    test_co_sleep(0.2);
+    read_sec(cb->bs, 5*BACKUP_CLUSTER_SIZE, buf);
+    write_sec_pattern_cd(cb->bs, 6*BACKUP_CLUSTER_SIZE);
+
+    cb->finished = true;
+}
+
+static void coroutine_fn run_co_random_read(void *opaque)
+{
+    assert(opaque);
+    TestCB *cb = (TestCB *)opaque;
+    int64_t sectors = bdrv_getlength(cb->bs)/BDRV_SECTOR_SIZE - 1;
+    unsigned char buf[512];
+
+    while (1) {
+        test_co_yield();
+        if (request_term) {
+            DPRINTF("finish run_co_random_read\n");
+            break;
+        }
+        int64_t s = (rand()*sectors)/RAND_MAX;
+        read_sec(cb->bs, s*BDRV_SECTOR_SIZE, buf);
+    }
+
+    cb->finished = true;
+}
+
+static void coroutine_fn run_co_random_write(void *opaque)
+{
+    assert(opaque);
+    TestCB *cb = (TestCB *)opaque;
+    int64_t sectors = bdrv_getlength(cb->bs)/BDRV_SECTOR_SIZE;
+
+    while (1) {
+        test_co_yield();
+        if (request_term) {
+            DPRINTF("finish run_co_random_write\n");
+            break;
+        }
+        int64_t s = (rand()*sectors)/RAND_MAX;
+        write_sec_pattern_cd(cb->bs, s*BDRV_SECTOR_SIZE);
+    }
+
+    cb->finished = true;
+}
+
+static void fill_test_sector(void *buf, size_t sector_num)
+{
+    int64_t *i64buf = (int64_t *)buf;
+    int i;
+
+    int data = sector_num;
+    if (sector_num >= 8 && sector_num < 8*(2*16+2)) {
+        data = 0;  /* add zero region for testing */
+    }
+
+    for (i = 0; i < (512/sizeof(int64_t)); i++) {
+        i64buf[i] = data;
+    }
+}
+
+static void verify_archive(const char *archive, size_t size)
+{
+    Error *errp = NULL;
+
+    VmaReader *vmar = vma_reader_create(archive, &errp);
+
+    if (!vmar) {
+        g_error("%s", error_get_pretty(errp));
+    }
+
+    VmaDeviceInfo *di = vma_reader_get_device_info(vmar, 1);
+    if (!di || strcmp((char *)di->devname, "hda") || di->size != size) {
+        g_error("got wrong device info");
+    }
+
+    unlink(TEST_IMG_RESTORE_NAME);
+
+    int flags = BDRV_O_NATIVE_AIO|BDRV_O_RDWR|BDRV_O_CACHE_WB;
+
+    if (bdrv_img_create(TEST_IMG_RESTORE_NAME, "raw", NULL, NULL, NULL,
+                        size, flags)) {
+        g_error("can't create file %s", TEST_IMG_RESTORE_NAME);
+    }
+
+    BlockDriverState *bs = NULL;
+    if (bdrv_file_open(&bs, TEST_IMG_RESTORE_NAME, flags)) {
+        g_error("can't open file %s", TEST_IMG_RESTORE_NAME);
+    }
+    if (vma_reader_register_bs(vmar, 1, bs, false, &errp) < 0) {
+        g_error("%s", error_get_pretty(errp));
+    }
+
+    if (vma_reader_restore(vmar, &errp) < 0) {
+        g_error("restore failed - %s", error_get_pretty(errp));
+    }
+
+    size_t i;
+    size_t sectors = size/BDRV_SECTOR_SIZE;
+    int64_t buf[512/sizeof(int64_t)];
+    int64_t buf2[512/sizeof(int64_t)];
+
+    for (i = 0; i < sectors; i++) {
+        if (bdrv_read(bs, i, (uint8_t *)buf, 1) != 0) {
+            g_error("bdrv_read failed");
+        }
+        fill_test_sector(buf2, i);
+        if (bcmp(buf, buf2, sizeof(buf))) {
+            g_error("data is different at sector %zd", i);
+        }
+    }
+
+    vma_reader_destroy(vmar);
+
+    unlink(TEST_IMG_RESTORE_NAME);
+}
+
+static void prepare_vm_image(const char *filename, size_t sectors)
+{
+    int fd = open(filename, O_RDWR|O_CREAT|O_TRUNC, 0644);
+    if (fd < 0) {
+        g_error("can't open file %s\n", filename);
+    }
+
+    size_t i;
+    int64_t buf[512/sizeof(int64_t)];
+
+    for (i = 0; i < sectors; i++) {
+        fill_test_sector(buf, i);
+
+         int res = 0;
+        while (1) {
+            res = write(fd, buf, sizeof(buf));
+            if (!(res < 0 && errno == EINTR)) {
+                break;
+            }
+        }
+        if (res != sizeof(buf)) {
+            g_error("can't initialize file %s - %s %d\n",
+                    filename, strerror(errno), res);
+        }
+    }
+
+    if (close(fd) != 0) {
+        g_error("close failed");
+    }
+}
+
+static GList *simple_test(BlockDriverState *bs)
+{
+    GList *cb_list = NULL;
+
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_test1));
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_test2));
+
+    return cb_list;
+}
+
+static GList *random_read_write_test(BlockDriverState *bs)
+{
+    GList *cb_list = NULL;
+
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_random_read));
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_random_read));
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_random_write));
+    cb_list = g_list_append(cb_list, enter_test_co(bs, run_co_random_write));
+
+    return cb_list;
+}
+
+static void backup_test(const char *testname, int64_t speed,
+                        GList *(*start_test_cb)(BlockDriverState *bs))
+{
+    BlockDriverState *bs = bdrv_new("hda");
+
+    static int test_counter;
+
+    test_counter++;
+
+    printf("starting test #%d '%s'\n", test_counter, testname);
+
+    const char *filename = TEST_IMG_NAME;
+
+    prepare_vm_image(TEST_IMG_NAME, TEST_IMG_SIZE/BDRV_SECTOR_SIZE);
+
+    int flags = BDRV_O_NATIVE_AIO|BDRV_O_RDWR|BDRV_O_CACHE_WB;
+
+    if (bdrv_open(bs, filename, flags, NULL) < 0) {
+        g_error("can't open device %s\n", filename);
+    }
+
+    Error *err = NULL;
+
+    unlink(TEST_VMA_NAME);
+
+    VmaWriter *vmaw = vma_writer_create(TEST_VMA_NAME, speed, &err);
+    if (!vmaw) {
+        g_error("%s", error_get_pretty(err));
+    }
+
+    BackupCB bcb;
+    bcb.vmaw = vmaw;
+    bcb.dev_id = vma_writer_register_stream(vmaw, bdrv_get_device_name(bs),
+                                            bdrv_getlength(bs));
+    bdrv_backup_init(bs, backup_dump_cb, backup_complete_cb, &bcb);
+
+    request_term = false;
+
+    GList *cb_list = start_test_cb(bs);
+
+    while (1) {
+        main_loop_wait(false);
+
+        VmaStatus vmastat;
+        vma_writer_get_status(vmaw, &vmastat);
+        if (vmastat.closed) {
+            break;
+        }
+    }
+
+    request_term = true;
+
+    while (1) {
+        GList *l = cb_list;
+        bool active = 0;
+        while (l && l->data) {
+            TestCB *cb = (TestCB *)l->data;
+            l = g_list_next(l);
+            if (!cb->finished) {
+                active = true;
+                break;
+            }
+        }
+        if (!active) {
+            DPRINTF("All test coroutines finished\n");
+            break;
+        }
+        main_loop_wait(false);
+    }
+
+    /* Make sure all outstanding requests complete */
+    bdrv_drain_all();
+
+    VmaStatus vmastat;
+    vma_writer_get_status(vmaw, &vmastat);
+    DPRINTF("statistic %zd %zd\n", vmastat.stream_info[1].size,
+            vmastat.stream_info[1].transferred);
+    assert(vmastat.stream_info[1].size == vmastat.stream_info[1].transferred);
+
+    vma_writer_destroy(vmaw);
+
+    bdrv_delete(bs);
+
+    /* start verification */
+    verify_archive(TEST_VMA_NAME, TEST_IMG_SIZE);
+
+    bdrv_close_all();
+
+    unlink(TEST_IMG_NAME);
+    unlink(TEST_VMA_NAME);
+
+    printf("finish test #%d '%s' OK\n", test_counter, testname);
+}
+
+static void help(void)
+{
+    const char *help_msg =
+        "usage: backup-test [options]\n"
+        "\n"
+        "backup-test        run default regression test (fast)\n"
+        "backup-test -l     run long running test loop (endless)\n"
+        "\n"
+        "use option -d to turn on verbose debug output\n"
+        ;
+
+    printf("%s", help_msg);
+    exit(1);
+}
+
+int main(int argc, char **argv)
+{
+    int c;
+
+    for (;;) {
+        c = getopt(argc, argv, "hdl");
+        if (c == -1) {
+            break;
+        }
+        switch (c) {
+        case '?':
+        case 'h':
+            help();
+            break;
+        case 'd':
+            opt_debug = 1;
+            break;
+        case 'l':
+            opt_loop = 1;
+            break;
+        default:
+            g_assert_not_reached();
+        }
+    }
+
+    memset(buf_sec_pattern_cd, 0xcd, sizeof(buf_sec_pattern_cd));
+    memset(buf_sec_pattern_32, 0x32, sizeof(buf_sec_pattern_32));
+
+    srand(1234);
+
+    /* ignore SIGPIPE */
+    struct sigaction act;
+    sigfillset(&act.sa_mask);
+    act.sa_flags = 0;
+    act.sa_handler = SIG_IGN;
+    sigaction(SIGPIPE, &act, NULL);
+
+    qemu_init_main_loop();
+
+    bdrv_init();
+
+    if (opt_loop) { /* endless test loop */
+        while (1) {
+            RUN_TEST(random_read_write_test, 0);
+        }
+        return 0;
+    }
+
+    if (opt_debug) { /* run simple test (rate limited) */
+        RUN_TEST(simple_test, 1024*1024);
+        return 0;
+    }
+
+    /* run default regression tests at full speed */
+
+    RUN_TEST(simple_test, 0);
+    RUN_TEST(random_read_write_test, 0);
+
+    return 0;
+}
