diff --git a/block.c b/block.c
index c90c71a..40c5e1a 100644
--- a/block.c
+++ b/block.c
@@ -1274,6 +1274,33 @@
     g_free(tmp_filename);
 }
 
+static QDict *parse_json_filename(const char *filename, Error **errp)
+{
+    QObject *options_obj;
+    QDict *options;
+    int ret;
+
+    ret = strstart(filename, "json:", &filename);
+    assert(ret);
+
+    options_obj = qobject_from_json(filename);
+    if (!options_obj) {
+        error_setg(errp, "Could not parse the JSON options");
+        return NULL;
+    }
+
+    if (qobject_type(options_obj) != QTYPE_QDICT) {
+        qobject_decref(options_obj);
+        error_setg(errp, "Invalid JSON object given");
+        return NULL;
+    }
+
+    options = qobject_to_qdict(options_obj);
+    qdict_flatten(options);
+
+    return options;
+}
+
 /*
  * Opens a disk image (raw, qcow2, vmdk, ...)
  *
@@ -1337,6 +1364,20 @@
         options = qdict_new();
     }
 
+    if (filename && g_str_has_prefix(filename, "json:")) {
+        QDict *json_options = parse_json_filename(filename, &local_err);
+        if (local_err) {
+            ret = -EINVAL;
+            goto fail;
+        }
+
+        /* Options given in the filename have lower priority than options
+         * specified directly */
+        qdict_join(options, json_options, false);
+        QDECREF(json_options);
+        filename = NULL;
+    }
+
     bs->options = options;
     options = qdict_clone_shallow(options);
 
@@ -3248,6 +3289,15 @@
 
     ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req);
 
+    if (!ret && bs->detect_zeroes != BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF &&
+        !(flags & BDRV_REQ_ZERO_WRITE) && drv->bdrv_co_write_zeroes &&
+        qemu_iovec_is_zero(qiov)) {
+        flags |= BDRV_REQ_ZERO_WRITE;
+        if (bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP) {
+            flags |= BDRV_REQ_MAY_UNMAP;
+        }
+    }
+
     if (ret < 0) {
         /* Do nothing, write notifier decided to fail this request */
     } else if (flags & BDRV_REQ_ZERO_WRITE) {
@@ -3864,7 +3914,7 @@
 
     if (!bs->drv->bdrv_co_get_block_status) {
         *pnum = nb_sectors;
-        ret = BDRV_BLOCK_DATA;
+        ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED;
         if (bs->drv->protocol_name) {
             ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE);
         }
@@ -3883,6 +3933,10 @@
                                      *pnum, pnum);
     }
 
+    if (ret & (BDRV_BLOCK_DATA | BDRV_BLOCK_ZERO)) {
+        ret |= BDRV_BLOCK_ALLOCATED;
+    }
+
     if (!(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO)) {
         if (bdrv_unallocated_blocks_are_zero(bs)) {
             ret |= BDRV_BLOCK_ZERO;
@@ -3959,9 +4013,7 @@
     if (ret < 0) {
         return ret;
     }
-    return
-        (ret & BDRV_BLOCK_DATA) ||
-        ((ret & BDRV_BLOCK_ZERO) && !bdrv_has_zero_init(bs));
+    return (ret & BDRV_BLOCK_ALLOCATED);
 }
 
 /*
diff --git a/block/curl.c b/block/curl.c
index d2f1084..f491b0b 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -23,6 +23,7 @@
  */
 #include "qemu-common.h"
 #include "block/block_int.h"
+#include "qapi/qmp/qbool.h"
 #include <curl/curl.h>
 
 // #define DEBUG
@@ -37,6 +38,21 @@
 #if LIBCURL_VERSION_NUM >= 0x071000
 /* The multi interface timer callback was introduced in 7.16.0 */
 #define NEED_CURL_TIMER_CALLBACK
+#define HAVE_SOCKET_ACTION
+#endif
+
+#ifndef HAVE_SOCKET_ACTION
+/* If curl_multi_socket_action isn't available, define it statically here in
+ * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
+ * less efficient but still safe. */
+static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
+                                            curl_socket_t sockfd,
+                                            int ev_bitmask,
+                                            int *running_handles)
+{
+    return curl_multi_socket(multi_handle, sockfd, running_handles);
+}
+#define curl_multi_socket_action __curl_multi_socket_action
 #endif
 
 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
@@ -46,12 +62,16 @@
 #define CURL_NUM_STATES 8
 #define CURL_NUM_ACB    8
 #define SECTOR_SIZE     512
-#define READ_AHEAD_SIZE (256 * 1024)
+#define READ_AHEAD_DEFAULT (256 * 1024)
 
 #define FIND_RET_NONE   0
 #define FIND_RET_OK     1
 #define FIND_RET_WAIT   2
 
+#define CURL_BLOCK_OPT_URL       "url"
+#define CURL_BLOCK_OPT_READAHEAD "readahead"
+#define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
+
 struct BDRVCURLState;
 
 typedef struct CURLAIOCB {
@@ -88,6 +108,7 @@
     CURLState states[CURL_NUM_STATES];
     char *url;
     size_t readahead_size;
+    bool sslverify;
     bool accept_range;
 } BDRVCURLState;
 
@@ -354,6 +375,8 @@
             return NULL;
         }
         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
+        curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
+                         (long) s->sslverify);
         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
                          (void *)curl_read_cb);
@@ -396,43 +419,7 @@
 static void curl_parse_filename(const char *filename, QDict *options,
                                 Error **errp)
 {
-
-    #define RA_OPTSTR ":readahead="
-    char *file;
-    char *ra;
-    const char *ra_val;
-    int parse_state = 0;
-
-    file = g_strdup(filename);
-
-    /* Parse a trailing ":readahead=#:" param, if present. */
-    ra = file + strlen(file) - 1;
-    while (ra >= file) {
-        if (parse_state == 0) {
-            if (*ra == ':') {
-                parse_state++;
-            } else {
-                break;
-            }
-        } else if (parse_state == 1) {
-            if (*ra > '9' || *ra < '0') {
-                char *opt_start = ra - strlen(RA_OPTSTR) + 1;
-                if (opt_start > file &&
-                    strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
-                    ra_val = ra + 1;
-                    ra -= strlen(RA_OPTSTR) - 1;
-                    *ra = '\0';
-                    qdict_put(options, "readahead", qstring_from_str(ra_val));
-                }
-                break;
-            }
-        }
-        ra--;
-    }
-
-    qdict_put(options, "url", qstring_from_str(file));
-
-    g_free(file);
+    qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
 }
 
 static QemuOptsList runtime_opts = {
@@ -440,15 +427,20 @@
     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
     .desc = {
         {
-            .name = "url",
+            .name = CURL_BLOCK_OPT_URL,
             .type = QEMU_OPT_STRING,
             .help = "URL to open",
         },
         {
-            .name = "readahead",
+            .name = CURL_BLOCK_OPT_READAHEAD,
             .type = QEMU_OPT_SIZE,
             .help = "Readahead size",
         },
+        {
+            .name = CURL_BLOCK_OPT_SSLVERIFY,
+            .type = QEMU_OPT_BOOL,
+            .help = "Verify SSL certificate"
+        },
         { /* end of list */ }
     },
 };
@@ -477,14 +469,17 @@
         goto out_noclean;
     }
 
-    s->readahead_size = qemu_opt_get_size(opts, "readahead", READ_AHEAD_SIZE);
+    s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
+                                          READ_AHEAD_DEFAULT);
     if ((s->readahead_size & 0x1ff) != 0) {
         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
                    s->readahead_size);
         goto out_noclean;
     }
 
-    file = qemu_opt_get(opts, "url");
+    s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
+
+    file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
     if (file == NULL) {
         error_setg(errp, "curl block driver requires an 'url' option");
         goto out_noclean;
diff --git a/block/iscsi.c b/block/iscsi.c
index d649424..3892cc5 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -381,6 +381,7 @@
 }
 
 
+#if defined(LIBISCSI_FEATURE_IOVECTOR)
 static bool iscsi_allocationmap_is_allocated(IscsiLun *iscsilun,
                                              int64_t sector_num, int nb_sectors)
 {
@@ -393,9 +394,6 @@
                            sector_num / iscsilun->cluster_sectors) == size);
 }
 
-
-#if defined(LIBISCSI_FEATURE_IOVECTOR)
-
 static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,
                                                   int64_t sector_num,
                                                   int nb_sectors, int *pnum)
diff --git a/block/qapi.c b/block/qapi.c
index af11445..75f44f1 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -50,6 +50,7 @@
     }
 
     info->backing_file_depth = bdrv_get_backing_file_depth(bs);
+    info->detect_zeroes = bs->detect_zeroes;
 
     if (bs->io_limits_enabled) {
         ThrottleConfig cfg;
diff --git a/block/qcow.c b/block/qcow.c
index 937dd6d..7fd57d7 100644
--- a/block/qcow.c
+++ b/block/qcow.c
@@ -48,9 +48,10 @@
     uint64_t size; /* in bytes */
     uint8_t cluster_bits;
     uint8_t l2_bits;
+    uint16_t padding;
     uint32_t crypt_method;
     uint64_t l1_table_offset;
-} QCowHeader;
+} QEMU_PACKED QCowHeader;
 
 #define L2_CACHE_SIZE 16
 
@@ -60,7 +61,7 @@
     int cluster_sectors;
     int l2_bits;
     int l2_size;
-    int l1_size;
+    unsigned int l1_size;
     uint64_t cluster_offset_mask;
     uint64_t l1_table_offset;
     uint64_t *l1_table;
@@ -96,7 +97,8 @@
                      Error **errp)
 {
     BDRVQcowState *s = bs->opaque;
-    int len, i, shift, ret;
+    unsigned int len, i, shift;
+    int ret;
     QCowHeader header;
 
     ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
@@ -127,11 +129,25 @@
         goto fail;
     }
 
-    if (header.size <= 1 || header.cluster_bits < 9) {
-        error_setg(errp, "invalid value in qcow header");
+    if (header.size <= 1) {
+        error_setg(errp, "Image size is too small (must be at least 2 bytes)");
         ret = -EINVAL;
         goto fail;
     }
+    if (header.cluster_bits < 9 || header.cluster_bits > 16) {
+        error_setg(errp, "Cluster size must be between 512 and 64k");
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* l2_bits specifies number of entries; storing a uint64_t in each entry,
+     * so bytes = num_entries << 3. */
+    if (header.l2_bits < 9 - 3 || header.l2_bits > 16 - 3) {
+        error_setg(errp, "L2 table size must be between 512 and 64k");
+        ret = -EINVAL;
+        goto fail;
+    }
+
     if (header.crypt_method > QCOW_CRYPT_AES) {
         error_setg(errp, "invalid encryption method in qcow header");
         ret = -EINVAL;
@@ -151,7 +167,19 @@
 
     /* read the level 1 table */
     shift = s->cluster_bits + s->l2_bits;
-    s->l1_size = (header.size + (1LL << shift) - 1) >> shift;
+    if (header.size > UINT64_MAX - (1LL << shift)) {
+        error_setg(errp, "Image too large");
+        ret = -EINVAL;
+        goto fail;
+    } else {
+        uint64_t l1_size = (header.size + (1LL << shift) - 1) >> shift;
+        if (l1_size > INT_MAX / sizeof(uint64_t)) {
+            error_setg(errp, "Image too large");
+            ret = -EINVAL;
+            goto fail;
+        }
+        s->l1_size = l1_size;
+    }
 
     s->l1_table_offset = header.l1_table_offset;
     s->l1_table = g_malloc(s->l1_size * sizeof(uint64_t));
@@ -175,7 +203,9 @@
     if (header.backing_file_offset != 0) {
         len = header.backing_file_size;
         if (len > 1023) {
-            len = 1023;
+            error_setg(errp, "Backing file name too long");
+            ret = -EINVAL;
+            goto fail;
         }
         ret = bdrv_pread(bs->file, header.backing_file_offset,
                    bs->backing_file, len);
diff --git a/block/vhdx.c b/block/vhdx.c
index 509baaf..353c74d 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -473,7 +473,14 @@
         } else if (h2_seq > h1_seq) {
             s->curr_header = 1;
         } else {
-            goto fail;
+            /* The Microsoft Disk2VHD tool will create 2 identical
+             * headers, with identical sequence numbers.  If the headers are
+             * identical, don't consider the file corrupt */
+            if (!memcmp(header1, header2, sizeof(VHDXHeader))) {
+                s->curr_header = 0;
+            } else {
+                goto fail;
+            }
         }
     }
 
diff --git a/blockdev.c b/blockdev.c
index 7810e9f..1cbcc1c 100644
--- a/blockdev.c
+++ b/blockdev.c
@@ -288,6 +288,25 @@
     }
 }
 
+static inline int parse_enum_option(const char *lookup[], const char *buf,
+                                    int max, int def, Error **errp)
+{
+    int i;
+
+    if (!buf) {
+        return def;
+    }
+
+    for (i = 0; i < max; i++) {
+        if (!strcmp(buf, lookup[i])) {
+            return i;
+        }
+    }
+
+    error_setg(errp, "invalid parameter value: %s", buf);
+    return def;
+}
+
 static bool check_throttle_config(ThrottleConfig *cfg, Error **errp)
 {
     if (throttle_conflicting(cfg)) {
@@ -324,6 +343,7 @@
     QemuOpts *opts;
     const char *id;
     bool has_driver_specific_opts;
+    BlockdevDetectZeroesOptions detect_zeroes;
     BlockDriver *drv = NULL;
 
     /* Check common options by copying from bs_opts to opts, all other options
@@ -452,6 +472,24 @@
         }
     }
 
+    detect_zeroes =
+        parse_enum_option(BlockdevDetectZeroesOptions_lookup,
+                          qemu_opt_get(opts, "detect-zeroes"),
+                          BLOCKDEV_DETECT_ZEROES_OPTIONS_MAX,
+                          BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF,
+                          &error);
+    if (error) {
+        error_propagate(errp, error);
+        goto early_err;
+    }
+
+    if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP &&
+        !(bdrv_flags & BDRV_O_UNMAP)) {
+        error_setg(errp, "setting detect-zeroes to unmap is not allowed "
+                         "without setting discard operation to unmap");
+        goto early_err;
+    }
+
     /* init */
     dinfo = g_malloc0(sizeof(*dinfo));
     dinfo->id = g_strdup(qemu_opts_id(opts));
@@ -462,6 +500,7 @@
     }
     dinfo->bdrv->open_flags = snapshot ? BDRV_O_SNAPSHOT : 0;
     dinfo->bdrv->read_only = ro;
+    dinfo->bdrv->detect_zeroes = detect_zeroes;
     dinfo->refcount = 1;
     if (serial != NULL) {
         dinfo->serial = g_strdup(serial);
@@ -2455,6 +2494,10 @@
             .name = "copy-on-read",
             .type = QEMU_OPT_BOOL,
             .help = "copy read data from backing file into image file",
+        },{
+            .name = "detect-zeroes",
+            .type = QEMU_OPT_STRING,
+            .help = "try to optimize zero writes (off, on, unmap)",
         },
         { /* end of list */ }
     },
diff --git a/default-configs/s390x-softmmu.mak b/default-configs/s390x-softmmu.mak
index d843dc0..126d88d 100644
--- a/default-configs/s390x-softmmu.mak
+++ b/default-configs/s390x-softmmu.mak
@@ -1,3 +1,4 @@
 CONFIG_VIRTIO=y
 CONFIG_SCLPCONSOLE=y
-CONFIG_S390_FLIC=$(CONFIG_KVM)
+CONFIG_S390_FLIC=y
+CONFIG_S390_FLIC_KVM=$(CONFIG_KVM)
diff --git a/hmp.c b/hmp.c
index a9d0236..ccc35d4 100644
--- a/hmp.c
+++ b/hmp.c
@@ -341,6 +341,11 @@
                            info->value->inserted->backing_file_depth);
         }
 
+        if (info->value->inserted->detect_zeroes != BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF) {
+            monitor_printf(mon, "    Detect zeroes:    %s\n",
+                           BlockdevDetectZeroesOptions_lookup[info->value->inserted->detect_zeroes]);
+        }
+
         if (info->value->inserted->bps
             || info->value->inserted->bps_rd
             || info->value->inserted->bps_wr
diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs
index c8a2318..843864a 100644
--- a/hw/intc/Makefile.objs
+++ b/hw/intc/Makefile.objs
@@ -26,3 +26,4 @@
 obj-$(CONFIG_XICS_KVM) += xics_kvm.o
 obj-$(CONFIG_ALLWINNER_A10_PIC) += allwinner-a10-pic.o
 obj-$(CONFIG_S390_FLIC) += s390_flic.o
+obj-$(CONFIG_S390_FLIC_KVM) += s390_flic_kvm.o
diff --git a/hw/intc/s390_flic.c b/hw/intc/s390_flic.c
index b2ef3e3..03c5e89 100644
--- a/hw/intc/s390_flic.c
+++ b/hw/intc/s390_flic.c
@@ -1,322 +1,103 @@
 /*
- * QEMU S390x KVM floating interrupt controller (flic)
+ * QEMU S390x floating interrupt controller (flic)
  *
  * Copyright 2014 IBM Corp.
  * Author(s): Jens Freimann <jfrei@linux.vnet.ibm.com>
+ *            Cornelia Huck <cornelia.huck@de.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or (at
  * your option) any later version. See the COPYING file in the top-level
  * directory.
  */
 
-#include <sys/ioctl.h>
 #include "qemu/error-report.h"
 #include "hw/sysbus.h"
-#include "sysemu/kvm.h"
 #include "migration/qemu-file.h"
 #include "hw/s390x/s390_flic.h"
 #include "trace.h"
 
-#define FLIC_SAVE_INITIAL_SIZE getpagesize()
-#define FLIC_FAILED (-1UL)
-#define FLIC_SAVEVM_VERSION 1
+S390FLICState *s390_get_flic(void)
+{
+    S390FLICState *fs;
+
+    fs = S390_FLIC_COMMON(object_resolve_path(TYPE_KVM_S390_FLIC, NULL));
+    if (!fs) {
+        fs = S390_FLIC_COMMON(object_resolve_path(TYPE_QEMU_S390_FLIC, NULL));
+    }
+    return fs;
+}
 
 void s390_flic_init(void)
 {
     DeviceState *dev;
     int r;
 
-    if (kvm_enabled()) {
-        dev = qdev_create(NULL, "s390-flic");
-        object_property_add_child(qdev_get_machine(), "s390-flic",
-                                OBJECT(dev), NULL);
-        r = qdev_init(dev);
-        if (r) {
-            error_report("flic: couldn't create qdev");
-        }
+    dev = s390_flic_kvm_create();
+    if (!dev) {
+        dev = qdev_create(NULL, TYPE_QEMU_S390_FLIC);
+        object_property_add_child(qdev_get_machine(), TYPE_QEMU_S390_FLIC,
+                                  OBJECT(dev), NULL);
+    }
+    r = qdev_init(dev);
+    if (r) {
+        error_report("flic: couldn't create qdev");
     }
 }
 
-/**
- * flic_get_all_irqs - store all pending irqs in buffer
- * @buf: pointer to buffer which is passed to kernel
- * @len: length of buffer
- * @flic: pointer to flic device state
- *
- * Returns: -ENOMEM if buffer is too small,
- * -EINVAL if attr.group is invalid,
- * -EFAULT if copying to userspace failed,
- * on success return number of stored interrupts
- */
-static int flic_get_all_irqs(KVMS390FLICState *flic,
-                             void *buf, int len)
+static int qemu_s390_register_io_adapter(S390FLICState *fs, uint32_t id,
+                                         uint8_t isc, bool swap,
+                                         bool is_maskable)
 {
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_FLIC_GET_ALL_IRQS,
-        .addr = (uint64_t) buf,
-        .attr = len,
-    };
-    int rc;
-
-    rc = ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr);
-
-    return rc == -1 ? -errno : rc;
+    /* nothing to do */
+    return 0;
 }
 
-static void flic_enable_pfault(KVMS390FLICState *flic)
+static int qemu_s390_io_adapter_map(S390FLICState *fs, uint32_t id,
+                                    uint64_t map_addr, bool do_map)
 {
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_FLIC_APF_ENABLE,
-    };
-    int rc;
-
-    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
-
-    if (rc) {
-        fprintf(stderr, "flic: couldn't enable pfault\n");
-    }
+    /* nothing to do */
+    return 0;
 }
 
-static void flic_disable_wait_pfault(KVMS390FLICState *flic)
+static int qemu_s390_add_adapter_routes(S390FLICState *fs,
+                                        AdapterRoutes *routes)
 {
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_FLIC_APF_DISABLE_WAIT,
-    };
-    int rc;
-
-    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
-
-    if (rc) {
-        fprintf(stderr, "flic: couldn't disable pfault\n");
-    }
+    return -ENOSYS;
 }
 
-/** flic_enqueue_irqs - returns 0 on success
- * @buf: pointer to buffer which is passed to kernel
- * @len: length of buffer
- * @flic: pointer to flic device state
- *
- * Returns: -EINVAL if attr.group is unknown
- */
-static int flic_enqueue_irqs(void *buf, uint64_t len,
-                            KVMS390FLICState *flic)
+static void qemu_s390_release_adapter_routes(S390FLICState *fs,
+                                             AdapterRoutes *routes)
 {
-    int rc;
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_FLIC_ENQUEUE,
-        .addr = (uint64_t) buf,
-        .attr = len,
-    };
-
-    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
-
-    return rc ? -errno : 0;
 }
 
-/**
- * __get_all_irqs - store all pending irqs in buffer
- * @flic: pointer to flic device state
- * @buf: pointer to pointer to a buffer
- * @len: length of buffer
- *
- * Returns: return value of flic_get_all_irqs
- * Note: Retry and increase buffer size until flic_get_all_irqs
- * either returns a value >= 0 or a negative error code.
- * -ENOMEM is an exception, which means the buffer is too small
- * and we should try again. Other negative error codes can be
- * -EFAULT and -EINVAL which we ignore at this point
- */
-static int __get_all_irqs(KVMS390FLICState *flic,
-                          void **buf, int len)
+static void qemu_s390_flic_class_init(ObjectClass *oc, void *data)
 {
-    int r;
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_CLASS(oc);
 
-    do {
-        /* returns -ENOMEM if buffer is too small and number
-         * of queued interrupts on success */
-        r = flic_get_all_irqs(flic, *buf, len);
-        if (r >= 0) {
-            break;
-        }
-        len *= 2;
-        *buf = g_try_realloc(*buf, len);
-        if (!buf) {
-            return -ENOMEM;
-        }
-    } while (r == -ENOMEM && len <= KVM_S390_FLIC_MAX_BUFFER);
-
-    return r;
+    fsc->register_io_adapter = qemu_s390_register_io_adapter;
+    fsc->io_adapter_map = qemu_s390_io_adapter_map;
+    fsc->add_adapter_routes = qemu_s390_add_adapter_routes;
+    fsc->release_adapter_routes = qemu_s390_release_adapter_routes;
 }
 
-/**
- * kvm_flic_save - Save pending floating interrupts
- * @f: QEMUFile containing migration state
- * @opaque: pointer to flic device state
- *
- * Note: Pass buf and len to kernel. Start with one page and
- * increase until buffer is sufficient or maxium size is
- * reached
- */
-static void kvm_flic_save(QEMUFile *f, void *opaque)
-{
-    KVMS390FLICState *flic = opaque;
-    int len = FLIC_SAVE_INITIAL_SIZE;
-    void *buf;
-    int count;
-
-    flic_disable_wait_pfault((struct KVMS390FLICState *) opaque);
-
-    buf = g_try_malloc0(len);
-    if (!buf) {
-        /* Storing FLIC_FAILED into the count field here will cause the
-         * target system to fail when attempting to load irqs from the
-         * migration state */
-        error_report("flic: couldn't allocate memory");
-        qemu_put_be64(f, FLIC_FAILED);
-        return;
-    }
-
-    count = __get_all_irqs(flic, &buf, len);
-    if (count < 0) {
-        error_report("flic: couldn't retrieve irqs from kernel, rc %d",
-                     count);
-        /* Storing FLIC_FAILED into the count field here will cause the
-         * target system to fail when attempting to load irqs from the
-         * migration state */
-        qemu_put_be64(f, FLIC_FAILED);
-    } else {
-        qemu_put_be64(f, count);
-        qemu_put_buffer(f, (uint8_t *) buf,
-                        count * sizeof(struct kvm_s390_irq));
-    }
-    g_free(buf);
-}
-
-/**
- * kvm_flic_load - Load pending floating interrupts
- * @f: QEMUFile containing migration state
- * @opaque: pointer to flic device state
- * @version_id: version id for migration
- *
- * Returns: value of flic_enqueue_irqs, -EINVAL on error
- * Note: Do nothing when no interrupts where stored
- * in QEMUFile
- */
-static int kvm_flic_load(QEMUFile *f, void *opaque, int version_id)
-{
-    uint64_t len = 0;
-    uint64_t count = 0;
-    void *buf = NULL;
-    int r = 0;
-
-    if (version_id != FLIC_SAVEVM_VERSION) {
-        r = -EINVAL;
-        goto out;
-    }
-
-    flic_enable_pfault((struct KVMS390FLICState *) opaque);
-
-    count = qemu_get_be64(f);
-    len = count * sizeof(struct kvm_s390_irq);
-    if (count == FLIC_FAILED) {
-        r = -EINVAL;
-        goto out;
-    }
-    if (count == 0) {
-        r = 0;
-        goto out;
-    }
-    buf = g_try_malloc0(len);
-    if (!buf) {
-        r = -ENOMEM;
-        goto out;
-    }
-
-    if (qemu_get_buffer(f, (uint8_t *) buf, len) != len) {
-        r = -EINVAL;
-        goto out_free;
-    }
-    r = flic_enqueue_irqs(buf, len, (struct KVMS390FLICState *) opaque);
-
-out_free:
-    g_free(buf);
-out:
-    return r;
-}
-
-static void kvm_s390_flic_realize(DeviceState *dev, Error **errp)
-{
-    KVMS390FLICState *flic_state = KVM_S390_FLIC(dev);
-    struct kvm_create_device cd = {0};
-    int ret;
-
-    flic_state->fd = -1;
-    if (!kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) {
-        trace_flic_no_device_api(errno);
-        return;
-    }
-
-    cd.type = KVM_DEV_TYPE_FLIC;
-    ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd);
-    if (ret < 0) {
-        trace_flic_create_device(errno);
-        return;
-    }
-    flic_state->fd = cd.fd;
-
-    /* Register savevm handler for floating interrupts */
-    register_savevm(NULL, "s390-flic", 0, 1, kvm_flic_save,
-                    kvm_flic_load, (void *) flic_state);
-}
-
-static void kvm_s390_flic_unrealize(DeviceState *dev, Error **errp)
-{
-    KVMS390FLICState *flic_state = KVM_S390_FLIC(dev);
-
-    unregister_savevm(DEVICE(flic_state), "s390-flic", flic_state);
-}
-
-static void kvm_s390_flic_reset(DeviceState *dev)
-{
-    KVMS390FLICState *flic = KVM_S390_FLIC(dev);
-    struct kvm_device_attr attr = {
-        .group = KVM_DEV_FLIC_CLEAR_IRQS,
-    };
-    int rc = 0;
-
-    if (flic->fd == -1) {
-        return;
-    }
-
-    flic_disable_wait_pfault(flic);
-
-    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
-    if (rc) {
-        trace_flic_reset_failed(errno);
-    }
-
-    flic_enable_pfault(flic);
-}
-
-static void kvm_s390_flic_class_init(ObjectClass *oc, void *data)
-{
-    DeviceClass *dc = DEVICE_CLASS(oc);
-
-    dc->realize = kvm_s390_flic_realize;
-    dc->unrealize = kvm_s390_flic_unrealize;
-    dc->reset = kvm_s390_flic_reset;
-}
-
-static const TypeInfo kvm_s390_flic_info = {
-    .name          = TYPE_KVM_S390_FLIC,
-    .parent        = TYPE_SYS_BUS_DEVICE,
-    .instance_size = sizeof(KVMS390FLICState),
-    .class_init    = kvm_s390_flic_class_init,
+static const TypeInfo qemu_s390_flic_info = {
+    .name          = TYPE_QEMU_S390_FLIC,
+    .parent        = TYPE_S390_FLIC_COMMON,
+    .instance_size = sizeof(QEMUS390FLICState),
+    .class_init    = qemu_s390_flic_class_init,
 };
 
-static void kvm_s390_flic_register_types(void)
+static const TypeInfo s390_flic_common_info = {
+    .name          = TYPE_S390_FLIC_COMMON,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(S390FLICState),
+    .class_size    = sizeof(S390FLICStateClass),
+};
+
+static void qemu_s390_flic_register_types(void)
 {
-    type_register_static(&kvm_s390_flic_info);
+    type_register_static(&s390_flic_common_info);
+    type_register_static(&qemu_s390_flic_info);
 }
 
-type_init(kvm_s390_flic_register_types)
+type_init(qemu_s390_flic_register_types)
diff --git a/hw/intc/s390_flic_kvm.c b/hw/intc/s390_flic_kvm.c
new file mode 100644
index 0000000..46c9e61
--- /dev/null
+++ b/hw/intc/s390_flic_kvm.c
@@ -0,0 +1,420 @@
+/*
+ * QEMU S390x KVM floating interrupt controller (flic)
+ *
+ * Copyright 2014 IBM Corp.
+ * Author(s): Jens Freimann <jfrei@linux.vnet.ibm.com>
+ *            Cornelia Huck <cornelia.huck@de.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#include <sys/ioctl.h>
+#include "qemu/error-report.h"
+#include "hw/sysbus.h"
+#include "sysemu/kvm.h"
+#include "migration/qemu-file.h"
+#include "hw/s390x/s390_flic.h"
+#include "hw/s390x/adapter.h"
+#include "trace.h"
+
+#define FLIC_SAVE_INITIAL_SIZE getpagesize()
+#define FLIC_FAILED (-1UL)
+#define FLIC_SAVEVM_VERSION 1
+
+typedef struct KVMS390FLICState {
+    S390FLICState parent_obj;
+
+    uint32_t fd;
+} KVMS390FLICState;
+
+DeviceState *s390_flic_kvm_create(void)
+{
+    DeviceState *dev = NULL;
+
+    if (kvm_enabled()) {
+        dev = qdev_create(NULL, TYPE_KVM_S390_FLIC);
+        object_property_add_child(qdev_get_machine(), TYPE_KVM_S390_FLIC,
+                                  OBJECT(dev), NULL);
+    }
+    return dev;
+}
+
+/**
+ * flic_get_all_irqs - store all pending irqs in buffer
+ * @buf: pointer to buffer which is passed to kernel
+ * @len: length of buffer
+ * @flic: pointer to flic device state
+ *
+ * Returns: -ENOMEM if buffer is too small,
+ * -EINVAL if attr.group is invalid,
+ * -EFAULT if copying to userspace failed,
+ * on success return number of stored interrupts
+ */
+static int flic_get_all_irqs(KVMS390FLICState *flic,
+                             void *buf, int len)
+{
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_GET_ALL_IRQS,
+        .addr = (uint64_t) buf,
+        .attr = len,
+    };
+    int rc;
+
+    rc = ioctl(flic->fd, KVM_GET_DEVICE_ATTR, &attr);
+
+    return rc == -1 ? -errno : rc;
+}
+
+static void flic_enable_pfault(KVMS390FLICState *flic)
+{
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_APF_ENABLE,
+    };
+    int rc;
+
+    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+
+    if (rc) {
+        fprintf(stderr, "flic: couldn't enable pfault\n");
+    }
+}
+
+static void flic_disable_wait_pfault(KVMS390FLICState *flic)
+{
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_APF_DISABLE_WAIT,
+    };
+    int rc;
+
+    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+
+    if (rc) {
+        fprintf(stderr, "flic: couldn't disable pfault\n");
+    }
+}
+
+/** flic_enqueue_irqs - returns 0 on success
+ * @buf: pointer to buffer which is passed to kernel
+ * @len: length of buffer
+ * @flic: pointer to flic device state
+ *
+ * Returns: -EINVAL if attr.group is unknown
+ */
+static int flic_enqueue_irqs(void *buf, uint64_t len,
+                            KVMS390FLICState *flic)
+{
+    int rc;
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_ENQUEUE,
+        .addr = (uint64_t) buf,
+        .attr = len,
+    };
+
+    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+
+    return rc ? -errno : 0;
+}
+
+/**
+ * __get_all_irqs - store all pending irqs in buffer
+ * @flic: pointer to flic device state
+ * @buf: pointer to pointer to a buffer
+ * @len: length of buffer
+ *
+ * Returns: return value of flic_get_all_irqs
+ * Note: Retry and increase buffer size until flic_get_all_irqs
+ * either returns a value >= 0 or a negative error code.
+ * -ENOMEM is an exception, which means the buffer is too small
+ * and we should try again. Other negative error codes can be
+ * -EFAULT and -EINVAL which we ignore at this point
+ */
+static int __get_all_irqs(KVMS390FLICState *flic,
+                          void **buf, int len)
+{
+    int r;
+
+    do {
+        /* returns -ENOMEM if buffer is too small and number
+         * of queued interrupts on success */
+        r = flic_get_all_irqs(flic, *buf, len);
+        if (r >= 0) {
+            break;
+        }
+        len *= 2;
+        *buf = g_try_realloc(*buf, len);
+        if (!buf) {
+            return -ENOMEM;
+        }
+    } while (r == -ENOMEM && len <= KVM_S390_FLIC_MAX_BUFFER);
+
+    return r;
+}
+
+static int kvm_s390_register_io_adapter(S390FLICState *fs, uint32_t id,
+                                        uint8_t isc, bool swap,
+                                        bool is_maskable)
+{
+    struct kvm_s390_io_adapter adapter = {
+        .id = id,
+        .isc = isc,
+        .maskable = is_maskable,
+        .swap = swap,
+    };
+    KVMS390FLICState *flic = KVM_S390_FLIC(fs);
+    int r, ret;
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_ADAPTER_REGISTER,
+        .addr = (uint64_t)&adapter,
+    };
+
+    if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) {
+        return -ENOSYS;
+    }
+
+    r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+
+    ret = r ? -errno : 0;
+    return ret;
+}
+
+static int kvm_s390_io_adapter_map(S390FLICState *fs, uint32_t id,
+                                   uint64_t map_addr, bool do_map)
+{
+    struct kvm_s390_io_adapter_req req = {
+        .id = id,
+        .type = do_map ? KVM_S390_IO_ADAPTER_MAP : KVM_S390_IO_ADAPTER_UNMAP,
+        .addr = map_addr,
+    };
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_ADAPTER_MODIFY,
+        .addr = (uint64_t)&req,
+    };
+    KVMS390FLICState *flic = KVM_S390_FLIC(fs);
+    int r;
+
+    if (!kvm_check_extension(kvm_state, KVM_CAP_IRQ_ROUTING)) {
+        return -ENOSYS;
+    }
+
+    r = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+    return r ? -errno : 0;
+}
+
+static int kvm_s390_add_adapter_routes(S390FLICState *fs,
+                                       AdapterRoutes *routes)
+{
+    int ret, i;
+    uint64_t ind_offset = routes->adapter.ind_offset;
+
+    for (i = 0; i < routes->num_routes; i++) {
+        ret = kvm_irqchip_add_adapter_route(kvm_state, &routes->adapter);
+        if (ret < 0) {
+            goto out_undo;
+        }
+        routes->gsi[i] = ret;
+        routes->adapter.ind_offset++;
+    }
+    /* Restore passed-in structure to original state. */
+    routes->adapter.ind_offset = ind_offset;
+    return 0;
+out_undo:
+    while (--i >= 0) {
+        kvm_irqchip_release_virq(kvm_state, routes->gsi[i]);
+        routes->gsi[i] = -1;
+    }
+    routes->adapter.ind_offset = ind_offset;
+    return ret;
+}
+
+static void kvm_s390_release_adapter_routes(S390FLICState *fs,
+                                            AdapterRoutes *routes)
+{
+    int i;
+
+    for (i = 0; i < routes->num_routes; i++) {
+        if (routes->gsi[i] >= 0) {
+            kvm_irqchip_release_virq(kvm_state, routes->gsi[i]);
+            routes->gsi[i] = -1;
+        }
+    }
+}
+
+/**
+ * kvm_flic_save - Save pending floating interrupts
+ * @f: QEMUFile containing migration state
+ * @opaque: pointer to flic device state
+ *
+ * Note: Pass buf and len to kernel. Start with one page and
+ * increase until buffer is sufficient or maxium size is
+ * reached
+ */
+static void kvm_flic_save(QEMUFile *f, void *opaque)
+{
+    KVMS390FLICState *flic = opaque;
+    int len = FLIC_SAVE_INITIAL_SIZE;
+    void *buf;
+    int count;
+
+    flic_disable_wait_pfault((struct KVMS390FLICState *) opaque);
+
+    buf = g_try_malloc0(len);
+    if (!buf) {
+        /* Storing FLIC_FAILED into the count field here will cause the
+         * target system to fail when attempting to load irqs from the
+         * migration state */
+        error_report("flic: couldn't allocate memory");
+        qemu_put_be64(f, FLIC_FAILED);
+        return;
+    }
+
+    count = __get_all_irqs(flic, &buf, len);
+    if (count < 0) {
+        error_report("flic: couldn't retrieve irqs from kernel, rc %d",
+                     count);
+        /* Storing FLIC_FAILED into the count field here will cause the
+         * target system to fail when attempting to load irqs from the
+         * migration state */
+        qemu_put_be64(f, FLIC_FAILED);
+    } else {
+        qemu_put_be64(f, count);
+        qemu_put_buffer(f, (uint8_t *) buf,
+                        count * sizeof(struct kvm_s390_irq));
+    }
+    g_free(buf);
+}
+
+/**
+ * kvm_flic_load - Load pending floating interrupts
+ * @f: QEMUFile containing migration state
+ * @opaque: pointer to flic device state
+ * @version_id: version id for migration
+ *
+ * Returns: value of flic_enqueue_irqs, -EINVAL on error
+ * Note: Do nothing when no interrupts where stored
+ * in QEMUFile
+ */
+static int kvm_flic_load(QEMUFile *f, void *opaque, int version_id)
+{
+    uint64_t len = 0;
+    uint64_t count = 0;
+    void *buf = NULL;
+    int r = 0;
+
+    if (version_id != FLIC_SAVEVM_VERSION) {
+        r = -EINVAL;
+        goto out;
+    }
+
+    flic_enable_pfault((struct KVMS390FLICState *) opaque);
+
+    count = qemu_get_be64(f);
+    len = count * sizeof(struct kvm_s390_irq);
+    if (count == FLIC_FAILED) {
+        r = -EINVAL;
+        goto out;
+    }
+    if (count == 0) {
+        r = 0;
+        goto out;
+    }
+    buf = g_try_malloc0(len);
+    if (!buf) {
+        r = -ENOMEM;
+        goto out;
+    }
+
+    if (qemu_get_buffer(f, (uint8_t *) buf, len) != len) {
+        r = -EINVAL;
+        goto out_free;
+    }
+    r = flic_enqueue_irqs(buf, len, (struct KVMS390FLICState *) opaque);
+
+out_free:
+    g_free(buf);
+out:
+    return r;
+}
+
+static void kvm_s390_flic_realize(DeviceState *dev, Error **errp)
+{
+    KVMS390FLICState *flic_state = KVM_S390_FLIC(dev);
+    struct kvm_create_device cd = {0};
+    int ret;
+
+    flic_state->fd = -1;
+    if (!kvm_check_extension(kvm_state, KVM_CAP_DEVICE_CTRL)) {
+        trace_flic_no_device_api(errno);
+        return;
+    }
+
+    cd.type = KVM_DEV_TYPE_FLIC;
+    ret = kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd);
+    if (ret < 0) {
+        trace_flic_create_device(errno);
+        return;
+    }
+    flic_state->fd = cd.fd;
+
+    /* Register savevm handler for floating interrupts */
+    register_savevm(NULL, "s390-flic", 0, 1, kvm_flic_save,
+                    kvm_flic_load, (void *) flic_state);
+}
+
+static void kvm_s390_flic_unrealize(DeviceState *dev, Error **errp)
+{
+    KVMS390FLICState *flic_state = KVM_S390_FLIC(dev);
+
+    unregister_savevm(DEVICE(flic_state), "s390-flic", flic_state);
+}
+
+static void kvm_s390_flic_reset(DeviceState *dev)
+{
+    KVMS390FLICState *flic = KVM_S390_FLIC(dev);
+    struct kvm_device_attr attr = {
+        .group = KVM_DEV_FLIC_CLEAR_IRQS,
+    };
+    int rc = 0;
+
+    if (flic->fd == -1) {
+        return;
+    }
+
+    flic_disable_wait_pfault(flic);
+
+    rc = ioctl(flic->fd, KVM_SET_DEVICE_ATTR, &attr);
+    if (rc) {
+        trace_flic_reset_failed(errno);
+    }
+
+    flic_enable_pfault(flic);
+}
+
+static void kvm_s390_flic_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_CLASS(oc);
+
+    dc->realize = kvm_s390_flic_realize;
+    dc->unrealize = kvm_s390_flic_unrealize;
+    dc->reset = kvm_s390_flic_reset;
+    fsc->register_io_adapter = kvm_s390_register_io_adapter;
+    fsc->io_adapter_map = kvm_s390_io_adapter_map;
+    fsc->add_adapter_routes = kvm_s390_add_adapter_routes;
+    fsc->release_adapter_routes = kvm_s390_release_adapter_routes;
+}
+
+static const TypeInfo kvm_s390_flic_info = {
+    .name          = TYPE_KVM_S390_FLIC,
+    .parent        = TYPE_S390_FLIC_COMMON,
+    .instance_size = sizeof(KVMS390FLICState),
+    .class_init    = kvm_s390_flic_class_init,
+};
+
+static void kvm_s390_flic_register_types(void)
+{
+    type_register_static(&kvm_s390_flic_info);
+}
+
+type_init(kvm_s390_flic_register_types)
diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index 122cc7e..2678e44 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -16,6 +16,7 @@
 #include "ioinst.h"
 #include "css.h"
 #include "trace.h"
+#include "hw/s390x/s390_flic.h"
 
 typedef struct CrwContainer {
     CRW crw;
@@ -39,6 +40,13 @@
     ChpInfo chpids[MAX_CHPID + 1];
 } CssImage;
 
+typedef struct IoAdapter {
+    uint32_t id;
+    uint8_t type;
+    uint8_t isc;
+    QTAILQ_ENTRY(IoAdapter) sibling;
+} IoAdapter;
+
 typedef struct ChannelSubSys {
     QTAILQ_HEAD(, CrwContainer) pending_crws;
     bool do_crw_mchk;
@@ -49,6 +57,7 @@
     uint64_t chnmon_area;
     CssImage *css[MAX_CSSID + 1];
     uint8_t default_cssid;
+    QTAILQ_HEAD(, IoAdapter) io_adapters;
 } ChannelSubSys;
 
 static ChannelSubSys *channel_subsys;
@@ -69,6 +78,46 @@
     return 0;
 }
 
+int css_register_io_adapter(uint8_t type, uint8_t isc, bool swap,
+                            bool maskable, uint32_t *id)
+{
+    IoAdapter *adapter;
+    bool found = false;
+    int ret;
+    S390FLICState *fs = s390_get_flic();
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
+
+    *id = 0;
+    QTAILQ_FOREACH(adapter, &channel_subsys->io_adapters, sibling) {
+        if ((adapter->type == type) && (adapter->isc == isc)) {
+            *id = adapter->id;
+            found = true;
+            ret = 0;
+            break;
+        }
+        if (adapter->id >= *id) {
+            *id = adapter->id + 1;
+        }
+    }
+    if (found) {
+        goto out;
+    }
+    adapter = g_new0(IoAdapter, 1);
+    ret = fsc->register_io_adapter(fs, *id, isc, swap, maskable);
+    if (ret == 0) {
+        adapter->id = *id;
+        adapter->isc = isc;
+        adapter->type = type;
+        QTAILQ_INSERT_TAIL(&channel_subsys->io_adapters, adapter, sibling);
+    } else {
+        g_free(adapter);
+        fprintf(stderr, "Unexpected error %d when registering adapter %d\n",
+                ret, *id);
+    }
+out:
+    return ret;
+}
+
 uint16_t css_build_subchannel_id(SubchDev *sch)
 {
     if (channel_subsys->max_cssid > 0) {
@@ -1235,6 +1284,7 @@
     channel_subsys->do_crw_mchk = true;
     channel_subsys->crws_lost = false;
     channel_subsys->chnmon_active = false;
+    QTAILQ_INIT(&channel_subsys->io_adapters);
 }
 machine_init(css_init);
 
diff --git a/hw/s390x/css.h b/hw/s390x/css.h
index 220169e..6586106 100644
--- a/hw/s390x/css.h
+++ b/hw/s390x/css.h
@@ -98,4 +98,8 @@
                            int hotplugged, int add);
 void css_generate_chp_crws(uint8_t cssid, uint8_t chpid);
 void css_adapter_interrupt(uint8_t isc);
+
+#define CSS_IO_ADAPTER_VIRTIO 1
+int css_register_io_adapter(uint8_t type, uint8_t isc, bool swap,
+                            bool maskable, uint32_t *id);
 #endif
diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c
index 1cb4e2c..c4f21d3 100644
--- a/hw/s390x/virtio-ccw.c
+++ b/hw/s390x/virtio-ccw.c
@@ -21,12 +21,77 @@
 #include "hw/sysbus.h"
 #include "qemu/bitops.h"
 #include "hw/virtio/virtio-bus.h"
+#include "hw/s390x/adapter.h"
+#include "hw/s390x/s390_flic.h"
 
 #include "ioinst.h"
 #include "css.h"
 #include "virtio-ccw.h"
 #include "trace.h"
 
+static QTAILQ_HEAD(, IndAddr) indicator_addresses =
+    QTAILQ_HEAD_INITIALIZER(indicator_addresses);
+
+static IndAddr *get_indicator(hwaddr ind_addr, int len)
+{
+    IndAddr *indicator;
+
+    QTAILQ_FOREACH(indicator, &indicator_addresses, sibling) {
+        if (indicator->addr == ind_addr) {
+            indicator->refcnt++;
+            return indicator;
+        }
+    }
+    indicator = g_new0(IndAddr, 1);
+    indicator->addr = ind_addr;
+    indicator->len = len;
+    indicator->refcnt = 1;
+    QTAILQ_INSERT_TAIL(&indicator_addresses, indicator, sibling);
+    return indicator;
+}
+
+static int s390_io_adapter_map(AdapterInfo *adapter, uint64_t map_addr,
+                               bool do_map)
+{
+    S390FLICState *fs = s390_get_flic();
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
+
+    return fsc->io_adapter_map(fs, adapter->adapter_id, map_addr, do_map);
+}
+
+static void release_indicator(AdapterInfo *adapter, IndAddr *indicator)
+{
+    assert(indicator->refcnt > 0);
+    indicator->refcnt--;
+    if (indicator->refcnt > 0) {
+        return;
+    }
+    QTAILQ_REMOVE(&indicator_addresses, indicator, sibling);
+    if (indicator->map) {
+        s390_io_adapter_map(adapter, indicator->map, false);
+    }
+    g_free(indicator);
+}
+
+static int map_indicator(AdapterInfo *adapter, IndAddr *indicator)
+{
+    int ret;
+
+    if (indicator->map) {
+        return 0; /* already mapped is not an error */
+    }
+    indicator->map = indicator->addr;
+    ret = s390_io_adapter_map(adapter, indicator->map, true);
+    if ((ret != 0) && (ret != -ENOSYS)) {
+        goto out_err;
+    }
+    return 0;
+
+out_err:
+    indicator->map = 0;
+    return ret;
+}
+
 static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,
                                VirtioCcwDevice *dev);
 
@@ -445,7 +510,7 @@
             ret = -EFAULT;
         } else {
             indicators = ldq_phys(&address_space_memory, ccw.cda);
-            dev->indicators = indicators;
+            dev->indicators = get_indicator(indicators, sizeof(uint64_t));
             sch->curr_status.scsw.count = ccw.count - sizeof(indicators);
             ret = 0;
         }
@@ -465,7 +530,7 @@
             ret = -EFAULT;
         } else {
             indicators = ldq_phys(&address_space_memory, ccw.cda);
-            dev->indicators2 = indicators;
+            dev->indicators2 = get_indicator(indicators, sizeof(uint64_t));
             sch->curr_status.scsw.count = ccw.count - sizeof(indicators);
             ret = 0;
         }
@@ -517,13 +582,20 @@
                 ret = -EFAULT;
             } else {
                 len = hw_len;
-                dev->summary_indicator = thinint->summary_indicator;
-                dev->indicators = thinint->device_indicator;
+                dev->summary_indicator =
+                    get_indicator(thinint->summary_indicator, sizeof(uint8_t));
+                dev->indicators = get_indicator(thinint->device_indicator,
+                                                thinint->ind_bit / 8 + 1);
                 dev->thinint_isc = thinint->isc;
-                dev->ind_bit = thinint->ind_bit;
+                dev->routes.adapter.ind_offset = thinint->ind_bit;
+                dev->routes.adapter.summary_offset = 7;
                 cpu_physical_memory_unmap(thinint, hw_len, 0, hw_len);
-                sch->thinint_active = ((dev->indicators != 0) &&
-                                       (dev->summary_indicator != 0));
+                ret = css_register_io_adapter(CSS_IO_ADAPTER_VIRTIO,
+                                              dev->thinint_isc, true, false,
+                                              &dev->routes.adapter.adapter_id);
+                assert(ret == 0);
+                sch->thinint_active = ((dev->indicators != NULL) &&
+                                       (dev->summary_indicator != NULL));
                 sch->curr_status.scsw.count = ccw.count - len;
                 ret = 0;
             }
@@ -554,7 +626,7 @@
     sch->driver_data = dev;
     dev->sch = sch;
 
-    dev->indicators = 0;
+    dev->indicators = NULL;
 
     /* Initialize subchannel structure. */
     sch->channel_prog = 0x0;
@@ -693,7 +765,10 @@
         css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL);
         g_free(sch);
     }
-    dev->indicators = 0;
+    if (dev->indicators) {
+        release_indicator(&dev->routes.adapter, dev->indicators);
+        dev->indicators = NULL;
+    }
     return 0;
 }
 
@@ -950,17 +1025,19 @@
              * ind_bit indicates the start of the indicators in a big
              * endian notation.
              */
-            virtio_set_ind_atomic(sch, dev->indicators +
-                                  (dev->ind_bit + vector) / 8,
-                                  0x80 >> ((dev->ind_bit + vector) % 8));
-            if (!virtio_set_ind_atomic(sch, dev->summary_indicator,
+            uint64_t ind_bit = dev->routes.adapter.ind_offset;
+
+            virtio_set_ind_atomic(sch, dev->indicators->addr +
+                                  (ind_bit + vector) / 8,
+                                  0x80 >> ((ind_bit + vector) % 8));
+            if (!virtio_set_ind_atomic(sch, dev->summary_indicator->addr,
                                        0x01)) {
                 css_adapter_interrupt(dev->thinint_isc);
             }
         } else {
-            indicators = ldq_phys(&address_space_memory, dev->indicators);
+            indicators = ldq_phys(&address_space_memory, dev->indicators->addr);
             indicators |= 1ULL << vector;
-            stq_phys(&address_space_memory, dev->indicators, indicators);
+            stq_phys(&address_space_memory, dev->indicators->addr, indicators);
             css_conditional_io_interrupt(sch);
         }
     } else {
@@ -968,9 +1045,9 @@
             return;
         }
         vector = 0;
-        indicators = ldq_phys(&address_space_memory, dev->indicators2);
+        indicators = ldq_phys(&address_space_memory, dev->indicators2->addr);
         indicators |= 1ULL << vector;
-        stq_phys(&address_space_memory, dev->indicators2, indicators);
+        stq_phys(&address_space_memory, dev->indicators2->addr, indicators);
         css_conditional_io_interrupt(sch);
     }
 }
@@ -991,9 +1068,18 @@
     virtio_ccw_stop_ioeventfd(dev);
     virtio_reset(vdev);
     css_reset_sch(dev->sch);
-    dev->indicators = 0;
-    dev->indicators2 = 0;
-    dev->summary_indicator = 0;
+    if (dev->indicators) {
+        release_indicator(&dev->routes.adapter, dev->indicators);
+        dev->indicators = NULL;
+    }
+    if (dev->indicators2) {
+        release_indicator(&dev->routes.adapter, dev->indicators2);
+        dev->indicators2 = NULL;
+    }
+    if (dev->summary_indicator) {
+        release_indicator(&dev->routes.adapter, dev->summary_indicator);
+        dev->summary_indicator = NULL;
+    }
 }
 
 static void virtio_ccw_vmstate_change(DeviceState *d, bool running)
@@ -1027,6 +1113,79 @@
     return virtio_ccw_set_guest2host_notifier(dev, n, assign, false);
 }
 
+static int virtio_ccw_get_mappings(VirtioCcwDevice *dev)
+{
+    int r;
+
+    if (!dev->sch->thinint_active) {
+        return -EINVAL;
+    }
+
+    r = map_indicator(&dev->routes.adapter, dev->summary_indicator);
+    if (r) {
+        return r;
+    }
+    r = map_indicator(&dev->routes.adapter, dev->indicators);
+    if (r) {
+        return r;
+    }
+    dev->routes.adapter.summary_addr = dev->summary_indicator->map;
+    dev->routes.adapter.ind_addr = dev->indicators->map;
+
+    return 0;
+}
+
+static int virtio_ccw_setup_irqroutes(VirtioCcwDevice *dev, int nvqs)
+{
+    int i;
+    VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
+    int ret;
+    S390FLICState *fs = s390_get_flic();
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
+
+    ret = virtio_ccw_get_mappings(dev);
+    if (ret) {
+        return ret;
+    }
+    for (i = 0; i < nvqs; i++) {
+        if (!virtio_queue_get_num(vdev, i)) {
+            break;
+        }
+    }
+    dev->routes.num_routes = i;
+    return fsc->add_adapter_routes(fs, &dev->routes);
+}
+
+static void virtio_ccw_release_irqroutes(VirtioCcwDevice *dev, int nvqs)
+{
+    S390FLICState *fs = s390_get_flic();
+    S390FLICStateClass *fsc = S390_FLIC_COMMON_GET_CLASS(fs);
+
+    fsc->release_adapter_routes(fs, &dev->routes);
+}
+
+static int virtio_ccw_add_irqfd(VirtioCcwDevice *dev, int n)
+{
+    VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
+    VirtQueue *vq = virtio_get_queue(vdev, n);
+    EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
+
+    return kvm_irqchip_add_irqfd_notifier(kvm_state, notifier, NULL,
+                                          dev->routes.gsi[n]);
+}
+
+static void virtio_ccw_remove_irqfd(VirtioCcwDevice *dev, int n)
+{
+    VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
+    VirtQueue *vq = virtio_get_queue(vdev, n);
+    EventNotifier *notifier = virtio_queue_get_guest_notifier(vq);
+    int ret;
+
+    ret = kvm_irqchip_remove_irqfd_notifier(kvm_state, notifier,
+                                            dev->routes.gsi[n]);
+    assert(ret == 0);
+}
+
 static int virtio_ccw_set_guest_notifier(VirtioCcwDevice *dev, int n,
                                          bool assign, bool with_irqfd)
 {
@@ -1042,11 +1201,17 @@
             return r;
         }
         virtio_queue_set_guest_notifier_fd_handler(vq, true, with_irqfd);
-        /* We do not support irqfd for classic I/O interrupts, because the
-         * classic interrupts are intermixed with the subchannel status, that
-         * is queried with test subchannel. We want to use vhost, though.
-         * Lets make sure to have vhost running and wire up the irq fd to
-         * land in qemu (and only the irq fd) in this code.
+        if (with_irqfd) {
+            r = virtio_ccw_add_irqfd(dev, n);
+            if (r) {
+                virtio_queue_set_guest_notifier_fd_handler(vq, false,
+                                                           with_irqfd);
+                return r;
+            }
+        }
+        /*
+         * We do not support individual masking for channel devices, so we
+         * need to manually trigger any guest masking callbacks here.
          */
         if (k->guest_notifier_mask) {
             k->guest_notifier_mask(vdev, n, false);
@@ -1060,6 +1225,9 @@
         if (k->guest_notifier_mask) {
             k->guest_notifier_mask(vdev, n, true);
         }
+        if (with_irqfd) {
+            virtio_ccw_remove_irqfd(dev, n);
+        }
         virtio_queue_set_guest_notifier_fd_handler(vq, false, with_irqfd);
         event_notifier_cleanup(notifier);
     }
@@ -1071,24 +1239,39 @@
 {
     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);
     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);
+    bool with_irqfd = dev->sch->thinint_active && kvm_irqfds_enabled();
     int r, n;
 
+    if (with_irqfd && assigned) {
+        /* irq routes need to be set up before assigning irqfds */
+        r = virtio_ccw_setup_irqroutes(dev, nvqs);
+        if (r < 0) {
+            goto irqroute_error;
+        }
+    }
     for (n = 0; n < nvqs; n++) {
         if (!virtio_queue_get_num(vdev, n)) {
             break;
         }
-        /* false -> true, as soon as irqfd works */
-        r = virtio_ccw_set_guest_notifier(dev, n, assigned, false);
+        r = virtio_ccw_set_guest_notifier(dev, n, assigned, with_irqfd);
         if (r < 0) {
             goto assign_error;
         }
     }
+    if (with_irqfd && !assigned) {
+        /* release irq routes after irqfds have been released */
+        virtio_ccw_release_irqroutes(dev, nvqs);
+    }
     return 0;
 
 assign_error:
     while (--n >= 0) {
         virtio_ccw_set_guest_notifier(dev, n, !assigned, false);
     }
+irqroute_error:
+    if (with_irqfd && assigned) {
+        virtio_ccw_release_irqroutes(dev, nvqs);
+    }
     return r;
 }
 
diff --git a/hw/s390x/virtio-ccw.h b/hw/s390x/virtio-ccw.h
index 4393e44..b8b8a8a 100644
--- a/hw/s390x/virtio-ccw.h
+++ b/hw/s390x/virtio-ccw.h
@@ -22,6 +22,7 @@
 #include <hw/virtio/virtio-balloon.h>
 #include <hw/virtio/virtio-rng.h>
 #include <hw/virtio/virtio-bus.h>
+#include <hw/s390x/s390_flic.h>
 
 #define VIRTUAL_CSSID 0xfe
 
@@ -75,6 +76,14 @@
 #define VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT 1
 #define VIRTIO_CCW_FLAG_USE_IOEVENTFD   (1 << VIRTIO_CCW_FLAG_USE_IOEVENTFD_BIT)
 
+typedef struct IndAddr {
+    hwaddr addr;
+    uint64_t map;
+    unsigned long refcnt;
+    int len;
+    QTAILQ_ENTRY(IndAddr) sibling;
+} IndAddr;
+
 struct VirtioCcwDevice {
     DeviceState parent_obj;
     SubchDev *sch;
@@ -85,10 +94,11 @@
     bool ioeventfd_disabled;
     uint32_t flags;
     uint8_t thinint_isc;
+    AdapterRoutes routes;
     /* Guest provided values: */
-    hwaddr indicators;
-    hwaddr indicators2;
-    hwaddr summary_indicator;
+    IndAddr *indicators;
+    IndAddr *indicators2;
+    IndAddr *summary_indicator;
     uint64_t ind_bit;
 };
 
diff --git a/hw/scsi/megasas.c b/hw/scsi/megasas.c
index baee46f..0e109a2 100644
--- a/hw/scsi/megasas.c
+++ b/hw/scsi/megasas.c
@@ -728,8 +728,8 @@
     snprintf(info.package_version, 0x60, "%s-QEMU", QEMU_VERSION);
     memcpy(info.image_component[0].name, "APP", 3);
     memcpy(info.image_component[0].version, MEGASAS_VERSION "-QEMU", 9);
-    memcpy(info.image_component[0].build_date, __DATE__, 11);
-    memcpy(info.image_component[0].build_time, __TIME__, 8);
+    memcpy(info.image_component[0].build_date, "Apr  1 2014", 11);
+    memcpy(info.image_component[0].build_time, "12:34:56", 8);
     info.image_component_count = 1;
     if (pci_dev->has_rom) {
         uint8_t biosver[32];
diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index abe7302..06399fa 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -938,6 +938,7 @@
         if (cmd->xfer == 0) {
             cmd->xfer = 256;
         }
+        /* fall through */
     case WRITE_10:
     case WRITE_VERIFY_10:
     case WRITE_12:
@@ -952,6 +953,7 @@
         if (cmd->xfer == 0) {
             cmd->xfer = 256;
         }
+        /* fall through */
     case READ_10:
     case RECOVER_BUFFERED_DATA:
     case READ_12:
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index 1752193..14261fb 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -498,7 +498,7 @@
                                    uint32_t event, uint32_t reason)
 {
     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
-    VirtIOSCSIReq *req = virtio_scsi_pop_req(s, vs->event_vq);
+    VirtIOSCSIReq *req;
     VirtIOSCSIEvent *evt;
     VirtIODevice *vdev = VIRTIO_DEVICE(s);
     int in_size;
@@ -507,6 +507,7 @@
         return;
     }
 
+    req = virtio_scsi_pop_req(s, vs->event_vq);
     if (!req) {
         s->events_dropped = true;
         return;
diff --git a/include/block/block.h b/include/block/block.h
index 1b119aa..59be83f 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -120,6 +120,8 @@
 /* BDRV_BLOCK_DATA: data is read from bs->file or another file
  * BDRV_BLOCK_ZERO: sectors read as zero
  * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data
+ * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
+ *                       layer (as opposed to the backing file)
  * BDRV_BLOCK_RAW: used internally to indicate that the request
  *                 was answered by the raw driver and that one
  *                 should look in bs->file directly.
@@ -141,10 +143,11 @@
  *  f    t        f       not allocated or unknown offset, read as zero
  *  f    f        f       not allocated or unknown offset, read from backing_hd
  */
-#define BDRV_BLOCK_DATA         1
-#define BDRV_BLOCK_ZERO         2
-#define BDRV_BLOCK_OFFSET_VALID 4
-#define BDRV_BLOCK_RAW          8
+#define BDRV_BLOCK_DATA         0x01
+#define BDRV_BLOCK_ZERO         0x02
+#define BDRV_BLOCK_OFFSET_VALID 0x04
+#define BDRV_BLOCK_RAW          0x08
+#define BDRV_BLOCK_ALLOCATED    0x10
 #define BDRV_BLOCK_OFFSET_MASK  BDRV_SECTOR_MASK
 
 typedef enum {
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 9ffcb69..b8cc926 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -364,6 +364,7 @@
     BlockJob *job;
 
     QDict *options;
+    BlockdevDetectZeroesOptions detect_zeroes;
 };
 
 int get_tmp_filename(char *filename, int size);
diff --git a/include/hw/s390x/adapter.h b/include/hw/s390x/adapter.h
new file mode 100644
index 0000000..7f17035
--- /dev/null
+++ b/include/hw/s390x/adapter.h
@@ -0,0 +1,23 @@
+/*
+ * s390 adapter definitions
+ *
+ * Copyright 2013,2014 IBM Corp.
+ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+
+#ifndef S390X_ADAPTER_H
+#define S390X_ADAPTER_H
+
+struct AdapterInfo {
+    uint64_t ind_addr;
+    uint64_t summary_addr;
+    uint64_t ind_offset;
+    uint32_t summary_offset;
+    uint32_t adapter_id;
+};
+
+#endif
diff --git a/include/hw/s390x/s390_flic.h b/include/hw/s390x/s390_flic.h
index 497b219..489d73b 100644
--- a/include/hw/s390x/s390_flic.h
+++ b/include/hw/s390x/s390_flic.h
@@ -1,33 +1,76 @@
 /*
- * QEMU S390x KVM floating interrupt controller (flic)
+ * QEMU S390x floating interrupt controller (flic)
  *
  * Copyright 2014 IBM Corp.
  * Author(s): Jens Freimann <jfrei@linux.vnet.ibm.com>
+ *            Cornelia Huck <cornelia.huck@de.ibm.com>
  *
  * This work is licensed under the terms of the GNU GPL, version 2 or (at
  * your option) any later version. See the COPYING file in the top-level
  * directory.
  */
 
-#ifndef __KVM_S390_FLIC_H
-#define __KVM_S390_FLIC_H
+#ifndef __HW_S390_FLIC_H
+#define __HW_S390_FLIC_H
 
 #include "hw/sysbus.h"
+#include "hw/s390x/adapter.h"
+#include "hw/virtio/virtio.h"
 
-#define TYPE_KVM_S390_FLIC "s390-flic"
+typedef struct AdapterRoutes {
+    AdapterInfo adapter;
+    int num_routes;
+    int gsi[VIRTIO_PCI_QUEUE_MAX];
+} AdapterRoutes;
+
+#define TYPE_S390_FLIC_COMMON "s390-flic"
+#define S390_FLIC_COMMON(obj) \
+    OBJECT_CHECK(S390FLICState, (obj), TYPE_S390_FLIC_COMMON)
+
+typedef struct S390FLICState {
+    SysBusDevice parent_obj;
+
+} S390FLICState;
+
+#define S390_FLIC_COMMON_CLASS(klass) \
+    OBJECT_CLASS_CHECK(S390FLICStateClass, (klass), TYPE_S390_FLIC_COMMON)
+#define S390_FLIC_COMMON_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(S390FLICStateClass, (obj), TYPE_S390_FLIC_COMMON)
+
+typedef struct S390FLICStateClass {
+    DeviceClass parent_class;
+
+    int (*register_io_adapter)(S390FLICState *fs, uint32_t id, uint8_t isc,
+                               bool swap, bool maskable);
+    int (*io_adapter_map)(S390FLICState *fs, uint32_t id, uint64_t map_addr,
+                          bool do_map);
+    int (*add_adapter_routes)(S390FLICState *fs, AdapterRoutes *routes);
+    void (*release_adapter_routes)(S390FLICState *fs, AdapterRoutes *routes);
+} S390FLICStateClass;
+
+#define TYPE_KVM_S390_FLIC "s390-flic-kvm"
 #define KVM_S390_FLIC(obj) \
     OBJECT_CHECK(KVMS390FLICState, (obj), TYPE_KVM_S390_FLIC)
 
-typedef struct KVMS390FLICState {
-    SysBusDevice parent_obj;
+#define TYPE_QEMU_S390_FLIC "s390-flic-qemu"
+#define QEMU_S390_FLIC(obj) \
+    OBJECT_CHECK(QEMUS390FLICState, (obj), TYPE_QEMU_S390_FLIC)
 
-    uint32_t fd;
-} KVMS390FLICState;
+typedef struct QEMUS390FLICState {
+    S390FLICState parent_obj;
+} QEMUS390FLICState;
+
+void s390_flic_init(void);
+
+S390FLICState *s390_get_flic(void);
 
 #ifdef CONFIG_KVM
-void s390_flic_init(void);
+DeviceState *s390_flic_kvm_create(void);
 #else
-static inline void s390_flic_init(void) { }
+static inline DeviceState *s390_flic_kvm_create(void)
+{
+    return NULL;
+}
 #endif
 
-#endif /* __KVM_S390_FLIC_H */
+#endif /* __HW_S390_FLIC_H */
diff --git a/include/qapi/qmp/qdict.h b/include/qapi/qmp/qdict.h
index 1ddf97b..d68f4eb 100644
--- a/include/qapi/qmp/qdict.h
+++ b/include/qapi/qmp/qdict.h
@@ -16,6 +16,7 @@
 #include "qapi/qmp/qobject.h"
 #include "qapi/qmp/qlist.h"
 #include "qemu/queue.h"
+#include <stdbool.h>
 #include <stdint.h>
 
 #define QDICT_BUCKET_MAX 512
@@ -70,4 +71,6 @@
 void qdict_extract_subqdict(QDict *src, QDict **dst, const char *start);
 void qdict_array_split(QDict *src, QList **dst);
 
+void qdict_join(QDict *dest, QDict *src, bool overwrite);
+
 #endif /* QDICT_H */
diff --git a/include/qemu-common.h b/include/qemu-common.h
index 3f3fd60..66ceceb 100644
--- a/include/qemu-common.h
+++ b/include/qemu-common.h
@@ -318,6 +318,7 @@
 void qemu_iovec_concat_iov(QEMUIOVector *dst,
                            struct iovec *src_iov, unsigned int src_cnt,
                            size_t soffset, size_t sbytes);
+bool qemu_iovec_is_zero(QEMUIOVector *qiov);
 void qemu_iovec_destroy(QEMUIOVector *qiov);
 void qemu_iovec_reset(QEMUIOVector *qiov);
 size_t qemu_iovec_to_buf(QEMUIOVector *qiov, size_t offset,
diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
index 86bab12..5f20b0e 100644
--- a/include/qemu/typedefs.h
+++ b/include/qemu/typedefs.h
@@ -74,5 +74,6 @@
 typedef struct FWCfgState FWCfgState;
 typedef struct PcGuestInfo PcGuestInfo;
 typedef struct Range Range;
+typedef struct AdapterInfo AdapterInfo;
 
 #endif /* QEMU_TYPEDEFS_H */
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index e7ad9d1..e79e92c 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -300,7 +300,7 @@
         };                                                           \
         uint64_t args_tmp[] = { __VA_ARGS__ };                       \
         int i;                                                       \
-        for (i = 0; i < ARRAY_SIZE(args_tmp) &&                      \
+        for (i = 0; i < (int)ARRAY_SIZE(args_tmp) &&                 \
                      i < ARRAY_SIZE(cap.args); i++) {                \
             cap.args[i] = args_tmp[i];                               \
         }                                                            \
@@ -315,7 +315,7 @@
         };                                                           \
         uint64_t args_tmp[] = { __VA_ARGS__ };                       \
         int i;                                                       \
-        for (i = 0; i < ARRAY_SIZE(args_tmp) &&                      \
+        for (i = 0; i < (int)ARRAY_SIZE(args_tmp) &&                 \
                      i < ARRAY_SIZE(cap.args); i++) {                \
             cap.args[i] = args_tmp[i];                               \
         }                                                            \
@@ -363,6 +363,8 @@
 int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg);
 void kvm_irqchip_release_virq(KVMState *s, int virq);
 
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter);
+
 int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
                                    EventNotifier *rn, int virq);
 int kvm_irqchip_remove_irqfd_notifier(KVMState *s, EventNotifier *n, int virq);
diff --git a/kvm-all.c b/kvm-all.c
index a343ede..721a390 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -27,6 +27,7 @@
 #include "sysemu/sysemu.h"
 #include "hw/hw.h"
 #include "hw/pci/msi.h"
+#include "hw/s390x/adapter.h"
 #include "exec/gdbstub.h"
 #include "sysemu/kvm.h"
 #include "qemu/bswap.h"
@@ -1236,6 +1237,35 @@
     return kvm_vm_ioctl(s, KVM_IRQFD, &irqfd);
 }
 
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    struct kvm_irq_routing_entry kroute;
+    int virq;
+
+    if (!kvm_gsi_routing_enabled()) {
+        return -ENOSYS;
+    }
+
+    virq = kvm_irqchip_get_virq(s);
+    if (virq < 0) {
+        return virq;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_S390_ADAPTER;
+    kroute.flags = 0;
+    kroute.u.adapter.summary_addr = adapter->summary_addr;
+    kroute.u.adapter.ind_addr = adapter->ind_addr;
+    kroute.u.adapter.summary_offset = adapter->summary_offset;
+    kroute.u.adapter.ind_offset = adapter->ind_offset;
+    kroute.u.adapter.adapter_id = adapter->adapter_id;
+
+    kvm_add_routing_entry(s, &kroute);
+    kvm_irqchip_commit_routes(s);
+
+    return virq;
+}
+
 #else /* !KVM_CAP_IRQ_ROUTING */
 
 void kvm_init_irq_routing(KVMState *s)
@@ -1256,6 +1286,11 @@
     return -ENOSYS;
 }
 
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    return -ENOSYS;
+}
+
 static int kvm_irqchip_assign_irqfd(KVMState *s, int fd, int virq, bool assign)
 {
     abort();
@@ -1285,7 +1320,8 @@
     int ret;
 
     if (!qemu_opt_get_bool(qemu_get_machine_opts(), "kernel_irqchip", true) ||
-        !kvm_check_extension(s, KVM_CAP_IRQCHIP)) {
+        (!kvm_check_extension(s, KVM_CAP_IRQCHIP) &&
+         (kvm_vm_enable_cap(s, KVM_CAP_S390_IRQCHIP, 0) < 0))) {
         return 0;
     }
 
diff --git a/kvm-stub.c b/kvm-stub.c
index 8acda86..ac33d86 100644
--- a/kvm-stub.c
+++ b/kvm-stub.c
@@ -136,6 +136,11 @@
     return -ENOSYS;
 }
 
+int kvm_irqchip_add_adapter_route(KVMState *s, AdapterInfo *adapter)
+{
+    return -ENOSYS;
+}
+
 int kvm_irqchip_add_irqfd_notifier(KVMState *s, EventNotifier *n,
                                    EventNotifier *rn, int virq)
 {
diff --git a/linux-headers/asm-s390/kvm.h b/linux-headers/asm-s390/kvm.h
index c003c6a..98bedf3 100644
--- a/linux-headers/asm-s390/kvm.h
+++ b/linux-headers/asm-s390/kvm.h
@@ -15,6 +15,7 @@
 #include <linux/types.h>
 
 #define __KVM_S390
+#define __KVM_HAVE_GUEST_DEBUG
 
 /* Device control API: s390-specific devices */
 #define KVM_DEV_FLIC_GET_ALL_IRQS	1
@@ -54,6 +55,13 @@
 	__u64 addr;
 };
 
+/* kvm attr_group  on vm fd */
+#define KVM_S390_VM_MEM_CTRL		0
+
+/* kvm attributes for mem_ctrl */
+#define KVM_S390_VM_MEM_ENABLE_CMMA	0
+#define KVM_S390_VM_MEM_CLR_CMMA	1
+
 /* for KVM_GET_REGS and KVM_SET_REGS */
 struct kvm_regs {
 	/* general purpose regs for s390 */
@@ -72,11 +80,31 @@
 	__u64 fprs[16];
 };
 
+#define KVM_GUESTDBG_USE_HW_BP		0x00010000
+
+#define KVM_HW_BP			1
+#define KVM_HW_WP_WRITE			2
+#define KVM_SINGLESTEP			4
+
 struct kvm_debug_exit_arch {
+	__u64 addr;
+	__u8 type;
+	__u8 pad[7]; /* Should be set to 0 */
+};
+
+struct kvm_hw_breakpoint {
+	__u64 addr;
+	__u64 phys_addr;
+	__u64 len;
+	__u8 type;
+	__u8 pad[7]; /* Should be set to 0 */
 };
 
 /* for KVM_SET_GUEST_DEBUG */
 struct kvm_guest_debug_arch {
+	__u32 nr_hw_bp;
+	__u32 pad; /* Should be set to 0 */
+	struct kvm_hw_breakpoint *hw_bp;
 };
 
 #define KVM_SYNC_PREFIX (1UL << 0)
diff --git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index b278ab3..42ddc2c 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -416,6 +416,8 @@
 #define KVM_S390_INT_PFAULT_INIT	0xfffe0004u
 #define KVM_S390_INT_PFAULT_DONE	0xfffe0005u
 #define KVM_S390_MCHK			0xfffe1000u
+#define KVM_S390_INT_CLOCK_COMP		0xffff1004u
+#define KVM_S390_INT_CPU_TIMER		0xffff1005u
 #define KVM_S390_INT_VIRTIO		0xffff2603u
 #define KVM_S390_INT_SERVICE		0xffff2401u
 #define KVM_S390_INT_EMERGENCY		0xffff1201u
@@ -515,6 +517,7 @@
 	kvm_ioeventfd_flag_nr_pio,
 	kvm_ioeventfd_flag_nr_deassign,
 	kvm_ioeventfd_flag_nr_virtio_ccw_notify,
+	kvm_ioeventfd_flag_nr_fast_mmio,
 	kvm_ioeventfd_flag_nr_max,
 };
 
@@ -529,7 +532,7 @@
 struct kvm_ioeventfd {
 	__u64 datamatch;
 	__u64 addr;        /* legal pio/mmio address */
-	__u32 len;         /* 1, 2, 4, or 8 bytes    */
+	__u32 len;         /* 1, 2, 4, or 8 bytes; or 0 to ignore length */
 	__s32 fd;
 	__u32 flags;
 	__u8  pad[36];
@@ -743,6 +746,8 @@
 #define KVM_CAP_IOAPIC_POLARITY_IGNORED 97
 #define KVM_CAP_ENABLE_CAP_VM 98
 #define KVM_CAP_S390_IRQCHIP 99
+#define KVM_CAP_IOEVENTFD_NO_LENGTH 100
+#define KVM_CAP_VM_ATTRIBUTES 101
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
diff --git a/qapi-schema.json b/qapi-schema.json
index 36cb964..70ed7e3 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -942,6 +942,8 @@
 # @encryption_key_missing: true if the backing device is encrypted but an
 #                          valid encryption key is missing
 #
+# @detect_zeroes: detect and optimize zero writes (Since 2.1)
+#
 # @bps: total throughput limit in bytes per second is specified
 #
 # @bps_rd: read throughput limit in bytes per second is specified
@@ -977,6 +979,7 @@
   'data': { 'file': 'str', '*node-name': 'str', 'ro': 'bool', 'drv': 'str',
             '*backing_file': 'str', 'backing_file_depth': 'int',
             'encrypted': 'bool', 'encryption_key_missing': 'bool',
+            'detect_zeroes': 'BlockdevDetectZeroesOptions',
             'bps': 'int', 'bps_rd': 'int', 'bps_wr': 'int',
             'iops': 'int', 'iops_rd': 'int', 'iops_wr': 'int',
             'image': 'ImageInfo',
@@ -4255,6 +4258,22 @@
   'data': [ 'ignore', 'unmap' ] }
 
 ##
+# @BlockdevDetectZeroesOptions
+#
+# Describes the operation mode for the automatic conversion of plain
+# zero writes by the OS to driver specific optimized zero write commands.
+#
+# @off:      Disabled (default)
+# @on:       Enabled
+# @unmap:    Enabled and even try to unmap blocks if possible. This requires
+#            also that @BlockdevDiscardOptions is set to unmap for this device.
+#
+# Since: 2.1
+##
+{ 'enum': 'BlockdevDetectZeroesOptions',
+  'data': [ 'off', 'on', 'unmap' ] }
+
+##
 # @BlockdevAioOptions
 #
 # Selects the AIO backend to handle I/O requests
@@ -4306,20 +4325,22 @@
 # Options that are available for all block devices, independent of the block
 # driver.
 #
-# @driver:      block driver name
-# @id:          #optional id by which the new block device can be referred to.
-#               This is a required option on the top level of blockdev-add, and
-#               currently not allowed on any other level.
-# @node-name:   #optional the name of a block driver state node (Since 2.0)
-# @discard:     #optional discard-related options (default: ignore)
-# @cache:       #optional cache-related options
-# @aio:         #optional AIO backend (default: threads)
-# @rerror:      #optional how to handle read errors on the device
-#               (default: report)
-# @werror:      #optional how to handle write errors on the device
-#               (default: enospc)
-# @read-only:   #optional whether the block device should be read-only
-#               (default: false)
+# @driver:        block driver name
+# @id:            #optional id by which the new block device can be referred to.
+#                 This is a required option on the top level of blockdev-add, and
+#                 currently not allowed on any other level.
+# @node-name:     #optional the name of a block driver state node (Since 2.0)
+# @discard:       #optional discard-related options (default: ignore)
+# @cache:         #optional cache-related options
+# @aio:           #optional AIO backend (default: threads)
+# @rerror:        #optional how to handle read errors on the device
+#                 (default: report)
+# @werror:        #optional how to handle write errors on the device
+#                 (default: enospc)
+# @read-only:     #optional whether the block device should be read-only
+#                 (default: false)
+# @detect-zeroes: #optional detect and optimize zero writes (Since 2.1)
+#                 (default: off)
 #
 # Since: 1.7
 ##
@@ -4332,7 +4353,8 @@
             '*aio': 'BlockdevAioOptions',
             '*rerror': 'BlockdevOnError',
             '*werror': 'BlockdevOnError',
-            '*read-only': 'bool' } }
+            '*read-only': 'bool',
+            '*detect-zeroes': 'BlockdevDetectZeroesOptions' } }
 
 ##
 # @BlockdevOptionsFile
diff --git a/qemu-img.c b/qemu-img.c
index 04ce02a..1ad899e 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -70,11 +70,8 @@
 {
     GSequence *seq = opaque;
 
-    if (!g_sequence_lookup(seq, (gpointer)fmt_name,
-                           compare_data, NULL)) {
-        g_sequence_insert_sorted(seq, (gpointer)fmt_name,
-                                 compare_data, NULL);
-    }
+    g_sequence_insert_sorted(seq, (gpointer)fmt_name,
+                             compare_data, NULL);
 }
 
 static void QEMU_NORETURN GCC_FMT_ATTR(1, 2) error_exit(const char *fmt, ...)
diff --git a/qemu-options.hx b/qemu-options.hx
index 781af14..c2c0823 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -414,6 +414,7 @@
     "       [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
     "       [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
     "       [,readonly=on|off][,copy-on-read=on|off]\n"
+    "       [,detect-zeroes=on|off|unmap]\n"
     "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
     "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
     "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
@@ -475,6 +476,11 @@
 @item copy-on-read=@var{copy-on-read}
 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
 file sectors into the image file.
+@item detect-zeroes=@var{detect-zeroes}
+@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
+conversion of plain zero writes by the OS to driver specific optimized
+zero write commands. You may even choose "unmap" if @var{discard} is set
+to "unmap" to allow a zero write to be converted to an UNMAP operation.
 @end table
 
 By default, the @option{cache=writeback} mode is used. It will report data
@@ -2191,6 +2197,74 @@
 @end example
 
 See also @url{http://www.gluster.org}.
+
+@item HTTP/HTTPS/FTP/FTPS/TFTP
+QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
+
+Syntax using a single filename:
+@example
+<protocol>://[<username>[:<password>]@@]<host>/<path>
+@end example
+
+where:
+@table @option
+@item protocol
+'http', 'https', 'ftp', 'ftps', or 'tftp'.
+
+@item username
+Optional username for authentication to the remote server.
+
+@item password
+Optional password for authentication to the remote server.
+
+@item host
+Address of the remote server.
+
+@item path
+Path on the remote server, including any query string.
+@end table
+
+The following options are also supported:
+@table @option
+@item url
+The full URL when passing options to the driver explicitly.
+
+@item readahead
+The amount of data to read ahead with each range request to the remote server.
+This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
+does not have a suffix, it will be assumed to be in bytes. The value must be a
+multiple of 512 bytes. It defaults to 256k.
+
+@item sslverify
+Whether to verify the remote server's certificate when connecting over SSL. It
+can have the value 'on' or 'off'. It defaults to 'on'.
+@end table
+
+Note that when passing options to qemu explicitly, @option{driver} is the value
+of <protocol>.
+
+Example: boot from a remote Fedora 20 live ISO image
+@example
+qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
+
+qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
+@end example
+
+Example: boot from a remote Fedora 20 cloud image using a local overlay for
+writes, copy-on-read, and a readahead of 64k
+@example
+qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
+
+qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
+@end example
+
+Example: boot from an image stored on a VMware vSphere server with a self-signed
+certificate using a local overlay for writes and a readahead of 64k
+@example
+qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k"@}' /tmp/test.qcow2
+
+qemu-system-x86_64 -drive file=/tmp/test.qcow2
+@end example
 ETEXI
 
 STEXI
diff --git a/qmp-commands.hx b/qmp-commands.hx
index cae890e..2c53c1b 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2032,6 +2032,8 @@
          - "iops_rd_max":  read I/O operations max (json-int)
          - "iops_wr_max":  write I/O operations max (json-int)
          - "iops_size": I/O size when limiting by iops (json-int)
+         - "detect_zeroes": detect and optimize zero writing (json-string)
+             - Possible values: "off", "on", "unmap"
          - "image": the detail of the image, it is a json-object containing
             the following:
              - "filename": image file name (json-string)
@@ -2108,6 +2110,7 @@
                "iops_rd_max": 0,
                "iops_wr_max": 0,
                "iops_size": 0,
+               "detect_zeroes": "on",
                "image":{
                   "filename":"disks/test.qcow2",
                   "format":"qcow2",
diff --git a/qobject/qdict.c b/qobject/qdict.c
index 42ec4c0..ea239f0 100644
--- a/qobject/qdict.c
+++ b/qobject/qdict.c
@@ -665,3 +665,35 @@
         qlist_append_obj(*dst, subqobj ?: QOBJECT(subqdict));
     }
 }
+
+/**
+ * qdict_join(): Absorb the src QDict into the dest QDict, that is, move all
+ * elements from src to dest.
+ *
+ * If an element from src has a key already present in dest, it will not be
+ * moved unless overwrite is true.
+ *
+ * If overwrite is true, the conflicting values in dest will be discarded and
+ * replaced by the corresponding values from src.
+ *
+ * Therefore, with overwrite being true, the src QDict will always be empty when
+ * this function returns. If overwrite is false, the src QDict will be empty
+ * iff there were no conflicts.
+ */
+void qdict_join(QDict *dest, QDict *src, bool overwrite)
+{
+    const QDictEntry *entry, *next;
+
+    entry = qdict_first(src);
+    while (entry) {
+        next = qdict_next(src, entry);
+
+        if (overwrite || !qdict_haskey(dest, entry->key)) {
+            qobject_incref(entry->value);
+            qdict_put_obj(dest, entry->key, entry->value);
+            qdict_del(src, entry->key);
+        }
+
+        entry = next;
+    }
+}
diff --git a/target-s390x/cpu-qom.h b/target-s390x/cpu-qom.h
index ac0460e..f9c96d1 100644
--- a/target-s390x/cpu-qom.h
+++ b/target-s390x/cpu-qom.h
@@ -86,6 +86,7 @@
 int s390_cpu_write_elf64_qemunote(WriteCoreDumpFunction f,
                                   CPUState *cpu, void *opaque);
 hwaddr s390_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
+hwaddr s390_cpu_get_phys_addr_debug(CPUState *cpu, vaddr addr);
 int s390_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
 int s390_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
 
diff --git a/target-s390x/helper.c b/target-s390x/helper.c
index 7c76fc1..3d756ca 100644
--- a/target-s390x/helper.c
+++ b/target-s390x/helper.c
@@ -489,6 +489,18 @@
     return raddr;
 }
 
+hwaddr s390_cpu_get_phys_addr_debug(CPUState *cs, vaddr vaddr)
+{
+    hwaddr phys_addr;
+    target_ulong page;
+
+    page = vaddr & TARGET_PAGE_MASK;
+    phys_addr = cpu_get_phys_page_debug(cs, page);
+    phys_addr += (vaddr & ~TARGET_PAGE_MASK);
+
+    return phys_addr;
+}
+
 void load_psw(CPUS390XState *env, uint64_t mask, uint64_t addr)
 {
     if (mask & PSW_MASK_WAIT) {
diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index 56179af..7a07f9d 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -36,6 +36,7 @@
 #include "sysemu/device_tree.h"
 #include "qapi/qmp/qjson.h"
 #include "monitor/monitor.h"
+#include "exec/gdbstub.h"
 #include "trace.h"
 
 /* #define DEBUG_KVM */
@@ -86,6 +87,14 @@
 #define ICPT_CPU_STOP                   0x28
 #define ICPT_IO                         0x40
 
+static CPUWatchpoint hw_watchpoint;
+/*
+ * We don't use a list because this structure is also used to transmit the
+ * hardware breakpoints to the kernel.
+ */
+static struct kvm_hw_breakpoint *hw_breakpoints;
+static int nb_hw_breakpoints;
+
 const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
     KVM_CAP_LAST_INFO
 };
@@ -320,12 +329,16 @@
     return mem == MAP_FAILED ? NULL : mem;
 }
 
+/* DIAG 501 is used for sw breakpoints */
+static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};
+
 int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
 {
-    static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};
 
-    if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 4, 0) ||
-        cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)diag_501, 4, 1)) {
+    if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,
+                            sizeof(diag_501), 0) ||
+        cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)diag_501,
+                            sizeof(diag_501), 1)) {
         return -EINVAL;
     }
     return 0;
@@ -333,38 +346,140 @@
 
 int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
 {
-    uint8_t t[4];
-    static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};
+    uint8_t t[sizeof(diag_501)];
 
-    if (cpu_memory_rw_debug(cs, bp->pc, t, 4, 0)) {
+    if (cpu_memory_rw_debug(cs, bp->pc, t, sizeof(diag_501), 0)) {
         return -EINVAL;
-    } else if (memcmp(t, diag_501, 4)) {
+    } else if (memcmp(t, diag_501, sizeof(diag_501))) {
         return -EINVAL;
-    } else if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 1, 1)) {
+    } else if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,
+                                   sizeof(diag_501), 1)) {
         return -EINVAL;
     }
 
     return 0;
 }
 
+static struct kvm_hw_breakpoint *find_hw_breakpoint(target_ulong addr,
+                                                    int len, int type)
+{
+    int n;
+
+    for (n = 0; n < nb_hw_breakpoints; n++) {
+        if (hw_breakpoints[n].addr == addr && hw_breakpoints[n].type == type &&
+            (hw_breakpoints[n].len == len || len == -1)) {
+            return &hw_breakpoints[n];
+        }
+    }
+
+    return NULL;
+}
+
+static int insert_hw_breakpoint(target_ulong addr, int len, int type)
+{
+    int size;
+
+    if (find_hw_breakpoint(addr, len, type)) {
+        return -EEXIST;
+    }
+
+    size = (nb_hw_breakpoints + 1) * sizeof(struct kvm_hw_breakpoint);
+
+    if (!hw_breakpoints) {
+        nb_hw_breakpoints = 0;
+        hw_breakpoints = (struct kvm_hw_breakpoint *)g_try_malloc(size);
+    } else {
+        hw_breakpoints =
+            (struct kvm_hw_breakpoint *)g_try_realloc(hw_breakpoints, size);
+    }
+
+    if (!hw_breakpoints) {
+        nb_hw_breakpoints = 0;
+        return -ENOMEM;
+    }
+
+    hw_breakpoints[nb_hw_breakpoints].addr = addr;
+    hw_breakpoints[nb_hw_breakpoints].len = len;
+    hw_breakpoints[nb_hw_breakpoints].type = type;
+
+    nb_hw_breakpoints++;
+
+    return 0;
+}
+
 int kvm_arch_insert_hw_breakpoint(target_ulong addr,
                                   target_ulong len, int type)
 {
-    return -ENOSYS;
+    switch (type) {
+    case GDB_BREAKPOINT_HW:
+        type = KVM_HW_BP;
+        break;
+    case GDB_WATCHPOINT_WRITE:
+        if (len < 1) {
+            return -EINVAL;
+        }
+        type = KVM_HW_WP_WRITE;
+        break;
+    default:
+        return -ENOSYS;
+    }
+    return insert_hw_breakpoint(addr, len, type);
 }
 
 int kvm_arch_remove_hw_breakpoint(target_ulong addr,
                                   target_ulong len, int type)
 {
-    return -ENOSYS;
+    int size;
+    struct kvm_hw_breakpoint *bp = find_hw_breakpoint(addr, len, type);
+
+    if (bp == NULL) {
+        return -ENOENT;
+    }
+
+    nb_hw_breakpoints--;
+    if (nb_hw_breakpoints > 0) {
+        /*
+         * In order to trim the array, move the last element to the position to
+         * be removed - if necessary.
+         */
+        if (bp != &hw_breakpoints[nb_hw_breakpoints]) {
+            *bp = hw_breakpoints[nb_hw_breakpoints];
+        }
+        size = nb_hw_breakpoints * sizeof(struct kvm_hw_breakpoint);
+        hw_breakpoints =
+             (struct kvm_hw_breakpoint *)g_realloc(hw_breakpoints, size);
+    } else {
+        g_free(hw_breakpoints);
+        hw_breakpoints = NULL;
+    }
+
+    return 0;
 }
 
 void kvm_arch_remove_all_hw_breakpoints(void)
 {
+    nb_hw_breakpoints = 0;
+    g_free(hw_breakpoints);
+    hw_breakpoints = NULL;
 }
 
 void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg)
 {
+    int i;
+
+    if (nb_hw_breakpoints > 0) {
+        dbg->arch.nr_hw_bp = nb_hw_breakpoints;
+        dbg->arch.hw_bp = hw_breakpoints;
+
+        for (i = 0; i < nb_hw_breakpoints; ++i) {
+            hw_breakpoints[i].phys_addr = s390_cpu_get_phys_addr_debug(cpu,
+                                                       hw_breakpoints[i].addr);
+        }
+        dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_HW_BP;
+    } else {
+        dbg->arch.nr_hw_bp = 0;
+        dbg->arch.hw_bp = NULL;
+    }
 }
 
 void kvm_arch_pre_run(CPUState *cpu, struct kvm_run *run)
@@ -579,6 +694,22 @@
     handle_diag_308(&cpu->env, r1, r3);
 }
 
+static int handle_sw_breakpoint(S390CPU *cpu, struct kvm_run *run)
+{
+    CPUS390XState *env = &cpu->env;
+    unsigned long pc;
+
+    cpu_synchronize_state(CPU(cpu));
+
+    pc = env->psw.addr - 4;
+    if (kvm_find_sw_breakpoint(CPU(cpu), pc)) {
+        env->psw.addr = pc;
+        return EXCP_DEBUG;
+    }
+
+    return -ENOENT;
+}
+
 #define DIAG_KVM_CODE_MASK 0x000000000000ffff
 
 static int handle_diag(S390CPU *cpu, struct kvm_run *run, uint32_t ipb)
@@ -599,7 +730,7 @@
         r = handle_hypercall(cpu, run);
         break;
     case DIAG_KVM_BREAKPOINT:
-        sleep(10);
+        r = handle_sw_breakpoint(cpu, run);
         break;
     default:
         DPRINTF("KVM: unknown DIAG: 0x%x\n", func_code);
@@ -701,7 +832,7 @@
     return 0;
 }
 
-static void handle_instruction(S390CPU *cpu, struct kvm_run *run)
+static int handle_instruction(S390CPU *cpu, struct kvm_run *run)
 {
     unsigned int ipa0 = (run->s390_sieic.ipa & 0xff00);
     uint8_t ipa1 = run->s390_sieic.ipa & 0x00ff;
@@ -728,8 +859,11 @@
     }
 
     if (r < 0) {
+        r = 0;
         enter_pgmcheck(cpu, 0x0001);
     }
+
+    return r;
 }
 
 static bool is_special_wait_psw(CPUState *cs)
@@ -749,7 +883,7 @@
             (long)cs->kvm_run->psw_addr);
     switch (icpt_code) {
         case ICPT_INSTRUCTION:
-            handle_instruction(cpu, run);
+            r = handle_instruction(cpu, run);
             break;
         case ICPT_WAITPSW:
             /* disabled wait, since enabled wait is handled in kernel */
@@ -830,7 +964,36 @@
 
 static int kvm_arch_handle_debug_exit(S390CPU *cpu)
 {
-    return -ENOSYS;
+    CPUState *cs = CPU(cpu);
+    struct kvm_run *run = cs->kvm_run;
+
+    int ret = 0;
+    struct kvm_debug_exit_arch *arch_info = &run->debug.arch;
+
+    switch (arch_info->type) {
+    case KVM_HW_WP_WRITE:
+        if (find_hw_breakpoint(arch_info->addr, -1, arch_info->type)) {
+            cs->watchpoint_hit = &hw_watchpoint;
+            hw_watchpoint.vaddr = arch_info->addr;
+            hw_watchpoint.flags = BP_MEM_WRITE;
+            ret = EXCP_DEBUG;
+        }
+        break;
+    case KVM_HW_BP:
+        if (find_hw_breakpoint(arch_info->addr, -1, arch_info->type)) {
+            ret = EXCP_DEBUG;
+        }
+        break;
+    case KVM_SINGLESTEP:
+        if (cs->singlestep_enabled) {
+            ret = EXCP_DEBUG;
+        }
+        break;
+    default:
+        ret = -ENOSYS;
+    }
+
+    return ret;
 }
 
 int kvm_arch_handle_exit(CPUState *cs, struct kvm_run *run)
@@ -911,6 +1074,16 @@
 
 void kvm_arch_init_irq_routing(KVMState *s)
 {
+    /*
+     * Note that while irqchip capabilities generally imply that cpustates
+     * are handled in-kernel, it is not true for s390 (yet); therefore, we
+     * have to override the common code kvm_halt_in_kernel_allowed setting.
+     */
+    if (kvm_check_extension(s, KVM_CAP_IRQ_ROUTING)) {
+        kvm_irqfds_allowed = true;
+        kvm_gsi_routing_allowed = true;
+        kvm_halt_in_kernel_allowed = false;
+    }
 }
 
 int kvm_s390_assign_subch_ioeventfd(EventNotifier *notifier, uint32_t sch,
diff --git a/tests/check-qdict.c b/tests/check-qdict.c
index 2ad0f78..a9296f0 100644
--- a/tests/check-qdict.c
+++ b/tests/check-qdict.c
@@ -444,6 +444,92 @@
     QDECREF(test_dict);
 }
 
+static void qdict_join_test(void)
+{
+    QDict *dict1, *dict2;
+    bool overwrite = false;
+    int i;
+
+    dict1 = qdict_new();
+    dict2 = qdict_new();
+
+
+    /* Test everything once without overwrite and once with */
+    do
+    {
+        /* Test empty dicts */
+        qdict_join(dict1, dict2, overwrite);
+
+        g_assert(qdict_size(dict1) == 0);
+        g_assert(qdict_size(dict2) == 0);
+
+
+        /* First iteration: Test movement */
+        /* Second iteration: Test empty source and non-empty destination */
+        qdict_put(dict2, "foo", qint_from_int(42));
+
+        for (i = 0; i < 2; i++) {
+            qdict_join(dict1, dict2, overwrite);
+
+            g_assert(qdict_size(dict1) == 1);
+            g_assert(qdict_size(dict2) == 0);
+
+            g_assert(qdict_get_int(dict1, "foo") == 42);
+        }
+
+
+        /* Test non-empty source and destination without conflict */
+        qdict_put(dict2, "bar", qint_from_int(23));
+
+        qdict_join(dict1, dict2, overwrite);
+
+        g_assert(qdict_size(dict1) == 2);
+        g_assert(qdict_size(dict2) == 0);
+
+        g_assert(qdict_get_int(dict1, "foo") == 42);
+        g_assert(qdict_get_int(dict1, "bar") == 23);
+
+
+        /* Test conflict */
+        qdict_put(dict2, "foo", qint_from_int(84));
+
+        qdict_join(dict1, dict2, overwrite);
+
+        g_assert(qdict_size(dict1) == 2);
+        g_assert(qdict_size(dict2) == !overwrite);
+
+        g_assert(qdict_get_int(dict1, "foo") == overwrite ? 84 : 42);
+        g_assert(qdict_get_int(dict1, "bar") == 23);
+
+        if (!overwrite) {
+            g_assert(qdict_get_int(dict2, "foo") == 84);
+        }
+
+
+        /* Check the references */
+        g_assert(qdict_get(dict1, "foo")->refcnt == 1);
+        g_assert(qdict_get(dict1, "bar")->refcnt == 1);
+
+        if (!overwrite) {
+            g_assert(qdict_get(dict2, "foo")->refcnt == 1);
+        }
+
+
+        /* Clean up */
+        qdict_del(dict1, "foo");
+        qdict_del(dict1, "bar");
+
+        if (!overwrite) {
+            qdict_del(dict2, "foo");
+        }
+    }
+    while (overwrite ^= true);
+
+
+    QDECREF(dict1);
+    QDECREF(dict2);
+}
+
 /*
  * Errors test-cases
  */
@@ -584,6 +670,7 @@
     g_test_add_func("/public/iterapi", qdict_iterapi_test);
     g_test_add_func("/public/flatten", qdict_flatten_test);
     g_test_add_func("/public/array_split", qdict_array_split_test);
+    g_test_add_func("/public/join", qdict_join_test);
 
     g_test_add_func("/errors/put_exists", qdict_put_exists_test);
     g_test_add_func("/errors/get_not_exists", qdict_get_not_exists_test);
diff --git a/tests/qemu-iotests/030 b/tests/qemu-iotests/030
index 8cb61fd..8ce2373 100755
--- a/tests/qemu-iotests/030
+++ b/tests/qemu-iotests/030
@@ -35,7 +35,7 @@
         qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % backing_img, mid_img)
         qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % mid_img, test_img)
         qemu_io('-c', 'write -P 0x1 0 512', backing_img)
-        self.vm = iotests.VM().add_drive(test_img)
+        self.vm = iotests.VM().add_drive("blkdebug::" + test_img)
         self.vm.launch()
 
     def tearDown(self):
diff --git a/tests/qemu-iotests/039 b/tests/qemu-iotests/039
index b9cbe99..27fe4bd 100755
--- a/tests/qemu-iotests/039
+++ b/tests/qemu-iotests/039
@@ -47,6 +47,11 @@
 _default_cache_mode "writethrough"
 _supported_cache_modes "writethrough"
 
+_no_dump_exec()
+{
+    (ulimit -c 0; exec "$@")
+}
+
 size=128M
 
 echo
@@ -67,10 +72,7 @@
 IMGOPTS="compat=1.1,lazy_refcounts=on"
 _make_test_img $size
 
-old_ulimit=$(ulimit -c)
-ulimit -c 0 # do not produce a core dump on abort(3)
-$QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" | _filter_qemu_io
-ulimit -c "$old_ulimit"
+_no_dump_exec $QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" 2>&1 | _filter_qemu_io
 
 # The dirty bit must be set
 ./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
@@ -103,10 +105,7 @@
 IMGOPTS="compat=1.1,lazy_refcounts=on"
 _make_test_img $size
 
-old_ulimit=$(ulimit -c)
-ulimit -c 0 # do not produce a core dump on abort(3)
-$QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" | _filter_qemu_io
-ulimit -c "$old_ulimit"
+_no_dump_exec $QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" 2>&1 | _filter_qemu_io
 
 # The dirty bit must be set
 ./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
@@ -122,10 +121,7 @@
 IMGOPTS="compat=1.1,lazy_refcounts=off"
 _make_test_img $size
 
-old_ulimit=$(ulimit -c)
-ulimit -c 0 # do not produce a core dump on abort(3)
-$QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" | _filter_qemu_io
-ulimit -c "$old_ulimit"
+_no_dump_exec $QEMU_IO -c "write -P 0x5a 0 512" -c "abort" "$TEST_IMG" 2>&1 | _filter_qemu_io
 
 # The dirty bit must not be set since lazy_refcounts=off
 ./qcow2.py "$TEST_IMG" dump-header | grep incompatible_features
diff --git a/tests/qemu-iotests/039.out b/tests/qemu-iotests/039.out
index fb31ae0..67e7744 100644
--- a/tests/qemu-iotests/039.out
+++ b/tests/qemu-iotests/039.out
@@ -11,6 +11,7 @@
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
 wrote 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+./039: Aborted                 ( ulimit -c 0; exec "$@" )
 incompatible_features     0x1
 ERROR cluster 5 refcount=0 reference=1
 ERROR OFLAG_COPIED data cluster: l2_entry=8000000000050000 refcount=0
@@ -42,6 +43,7 @@
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
 wrote 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+./039: Aborted                 ( ulimit -c 0; exec "$@" )
 incompatible_features     0x1
 Repairing cluster 5 refcount=0 reference=1
 wrote 512/512 bytes at offset 0
@@ -52,6 +54,7 @@
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728 
 wrote 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+./039: Aborted                 ( ulimit -c 0; exec "$@" )
 incompatible_features     0x0
 No errors were found on the image.
 
diff --git a/tests/qemu-iotests/067.out b/tests/qemu-iotests/067.out
index 8d271cc..7e090b9 100644
--- a/tests/qemu-iotests/067.out
+++ b/tests/qemu-iotests/067.out
@@ -6,7 +6,7 @@
 Testing: -drive file=TEST_DIR/t.qcow2,format=qcow2,if=none,id=disk -device virtio-blk-pci,drive=disk,id=virtio0
 QMP_VERSION
 {"return": {}}
-{"return": [{"io-status": "ok", "device": "disk", "locked": false, "removable": false, "inserted": {"iops_rd": 0, "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "type": "unknown"}, {"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}]}
+{"return": [{"io-status": "ok", "device": "disk", "locked": false, "removable": false, "inserted": {"iops_rd": 0, "detect_zeroes": "off", "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "type": "unknown"}, {"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}]}
 {"return": {}}
 {"return": {}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "DEVICE_DELETED", "data": {"path": "/machine/peripheral/virtio0/virtio-backend"}}
@@ -24,7 +24,7 @@
 Testing: -drive file=TEST_DIR/t.qcow2,format=qcow2,if=none,id=disk
 QMP_VERSION
 {"return": {}}
-{"return": [{"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}, {"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}]}
+{"return": [{"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "detect_zeroes": "off", "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}, {"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}]}
 {"return": {}}
 {"return": {}}
 {"return": {}}
@@ -44,7 +44,7 @@
 QMP_VERSION
 {"return": {}}
 {"return": "OK\r\n"}
-{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
+{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "detect_zeroes": "off", "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
 {"return": {}}
 {"return": {}}
 {"return": {}}
@@ -64,14 +64,14 @@
 QMP_VERSION
 {"return": {}}
 {"return": {}}
-{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
+{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "detect_zeroes": "off", "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
 {"return": {}}
 {"return": {}}
 {"return": {}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "DEVICE_DELETED", "data": {"path": "/machine/peripheral/virtio0/virtio-backend"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "DEVICE_DELETED", "data": {"device": "virtio0", "path": "/machine/peripheral/virtio0"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "RESET"}
-{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"io-status": "ok", "device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
+{"return": [{"io-status": "ok", "device": "ide1-cd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "floppy0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"device": "sd0", "locked": false, "removable": true, "tray_open": false, "type": "unknown"}, {"io-status": "ok", "device": "disk", "locked": false, "removable": true, "inserted": {"iops_rd": 0, "detect_zeroes": "off", "image": {"virtual-size": 134217728, "filename": "TEST_DIR/t.qcow2", "cluster-size": 65536, "format": "qcow2", "actual-size": SIZE, "format-specific": {"type": "qcow2", "data": {"compat": "1.1", "lazy-refcounts": false}}, "dirty-flag": false}, "iops_wr": 0, "ro": false, "backing_file_depth": 0, "drv": "qcow2", "iops": 0, "bps_wr": 0, "encrypted": false, "bps": 0, "bps_rd": 0, "file": "TEST_DIR/t.qcow2", "encryption_key_missing": false}, "tray_open": false, "type": "unknown"}]}
 {"return": {}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "SHUTDOWN"}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "DEVICE_TRAY_MOVED", "data": {"device": "ide1-cd0", "tray-open": true}}
diff --git a/tests/qemu-iotests/070 b/tests/qemu-iotests/070
index ce71fa4..ea0dae7 100755
--- a/tests/qemu-iotests/070
+++ b/tests/qemu-iotests/070
@@ -72,6 +72,13 @@
 $QEMU_IO -r -c "read -pP 0xa5 0 18M" "$TEST_IMG" 2>&1 | _filter_testdir \
                                                       | _filter_qemu_io
 
+_cleanup_test_img
+_use_sample_img test-disk2vhd.vhdx.bz2
+
+echo
+echo "=== Verify image created by Disk2VHD can be opened ==="
+$QEMU_IMG info "$TEST_IMG" 2>&1 | _filter_testdir | _filter_qemu
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/070.out b/tests/qemu-iotests/070.out
index 922d62c..15f1fc1 100644
--- a/tests/qemu-iotests/070.out
+++ b/tests/qemu-iotests/070.out
@@ -18,4 +18,11 @@
 === Verify open image read-only succeeds after log replay ===
 read 18874368/18874368 bytes at offset 0
 18 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Verify image created by Disk2VHD can be opened ===
+image: TEST_DIR/test-disk2vhd.vhdx
+file format: vhdx
+virtual size: 256M (268435456 bytes)
+disk size: 260M
+cluster_size: 2097152
 *** done
diff --git a/tests/qemu-iotests/089 b/tests/qemu-iotests/089
new file mode 100755
index 0000000..ef47601
--- /dev/null
+++ b/tests/qemu-iotests/089
@@ -0,0 +1,130 @@
+#!/bin/bash
+#
+# Test case for support of JSON filenames
+#
+# Copyright (C) 2014 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+# creator
+owner=mreitz@redhat.com
+
+seq="$(basename $0)"
+echo "QA output created by $seq"
+
+here="$PWD"
+tmp=/tmp/$$
+status=1	# failure is the default!
+
+_cleanup()
+{
+	_cleanup_test_img
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+_supported_fmt qcow2
+_supported_proto file
+_supported_os Linux
+
+# Using an image filename containing quotation marks will render the JSON data
+# below invalid. In that case, we have little choice but simply not to run this
+# test.
+case $TEST_IMG in
+    *'"'*)
+        _notrun "image filename may not contain quotation marks"
+        ;;
+esac
+
+IMG_SIZE=64M
+
+# Taken from test 072
+echo
+echo "=== Testing nested image formats ==="
+echo
+
+TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE
+
+$QEMU_IO -c 'write -P 42 0 512' -c 'write -P 23 512 512' \
+         -c 'write -P 66 1024 512' "$TEST_IMG.base" | _filter_qemu_io
+
+$QEMU_IMG convert -f raw -O $IMGFMT "$TEST_IMG.base" "$TEST_IMG"
+
+$QEMU_IO -c 'read -P 42 0 512' -c 'read -P 23 512 512' \
+         -c 'read -P 66 1024 512' "json:{
+    \"driver\": \"$IMGFMT\",
+    \"file\": {
+        \"driver\": \"$IMGFMT\",
+        \"file\": {
+            \"filename\": \"$TEST_IMG\"
+        }
+    }
+}" | _filter_qemu_io
+
+# This should fail (see test 072)
+$QEMU_IO -c 'read -P 42 0 512' "$TEST_IMG" | _filter_qemu_io
+
+
+# Taken from test 071
+echo
+echo "=== Testing blkdebug ==="
+echo
+
+_make_test_img $IMG_SIZE
+
+$QEMU_IO -c 'write -P 42 0x38000 512' "$TEST_IMG" | _filter_qemu_io
+
+# The "image.filename" part tests whether "a": { "b": "c" } and "a.b": "c" do
+# the same (which they should).
+$QEMU_IO -c 'read -P 42 0x38000 512' "json:{
+    \"driver\": \"$IMGFMT\",
+    \"file\": {
+        \"driver\": \"blkdebug\",
+        \"inject-error\": [{
+            \"event\": \"l2_load\"
+        }],
+        \"image.filename\": \"$TEST_IMG\"
+    }
+}" | _filter_qemu_io
+
+
+echo
+echo "=== Testing qemu-img info output ==="
+echo
+
+$QEMU_IMG info "json:{\"driver\":\"qcow2\",\"file.filename\":\"$TEST_IMG\"}" \
+    | _filter_testdir | _filter_imgfmt
+
+
+echo
+echo "=== Testing option merging ==="
+echo
+
+# Both options given directly and those given in the filename should be used
+$QEMU_IO -c "open -o driver=qcow2 json:{\"file.filename\":\"$TEST_IMG\"}" \
+         -c "info" 2>&1 | _filter_testdir | _filter_imgfmt
+
+# Options given directly should be prioritized over those given in the filename
+$QEMU_IO -c "open -o driver=qcow2 json:{\"driver\":\"raw\",\"file.filename\":\"$TEST_IMG\"}" \
+         -c "info" 2>&1 | _filter_testdir | _filter_imgfmt
+
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/089.out b/tests/qemu-iotests/089.out
new file mode 100644
index 0000000..d6cf783
--- /dev/null
+++ b/tests/qemu-iotests/089.out
@@ -0,0 +1,54 @@
+QA output created by 089
+
+=== Testing nested image formats ===
+
+Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=67108864 
+wrote 512/512 bytes at offset 0
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 512/512 bytes at offset 512
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 512/512 bytes at offset 1024
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 512/512 bytes at offset 0
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 512/512 bytes at offset 512
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 512/512 bytes at offset 1024
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Pattern verification failed at offset 0, 512 bytes
+read 512/512 bytes at offset 0
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Testing blkdebug ===
+
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+wrote 512/512 bytes at offset 229376
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read failed: Input/output error
+
+=== Testing qemu-img info output ===
+
+image: TEST_DIR/t.IMGFMT
+file format: IMGFMT
+virtual size: 64M (67108864 bytes)
+disk size: 324K
+cluster_size: 65536
+Format specific information:
+    compat: 1.1
+    lazy refcounts: false
+
+=== Testing option merging ===
+
+format name: IMGFMT
+cluster size: 64 KiB
+vm state offset: 512 MiB
+Format specific information:
+    compat: 1.1
+    lazy refcounts: false
+format name: IMGFMT
+cluster size: 64 KiB
+vm state offset: 512 MiB
+Format specific information:
+    compat: 1.1
+    lazy refcounts: false
+*** done
diff --git a/tests/qemu-iotests/092 b/tests/qemu-iotests/092
new file mode 100755
index 0000000..a8c0c9c
--- /dev/null
+++ b/tests/qemu-iotests/092
@@ -0,0 +1,98 @@
+#!/bin/bash
+#
+# qcow1 format input validation tests
+#
+# Copyright (C) 2014 Red Hat, Inc.
+#
+# 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=kwolf@redhat.com
+
+seq=`basename $0`
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+
+_cleanup()
+{
+    rm -f $TEST_IMG.snap
+    _cleanup_test_img
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+_supported_fmt qcow
+_supported_proto generic
+_supported_os Linux
+
+offset_backing_file_offset=8
+offset_backing_file_size=16
+offset_size=24
+offset_cluster_bits=32
+offset_l2_bits=33
+
+echo
+echo "== Invalid cluster size =="
+_make_test_img 64M
+poke_file "$TEST_IMG" "$offset_cluster_bits" "\xff"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_cluster_bits" "\x1f"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_cluster_bits" "\x08"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_cluster_bits" "\x11"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+echo
+echo "== Invalid L2 table size =="
+_make_test_img 64M
+poke_file "$TEST_IMG" "$offset_l2_bits" "\xff"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_l2_bits" "\x05"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_l2_bits" "\x0e"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+# 1 << 0x1b = 2^31 / L2_CACHE_SIZE
+poke_file "$TEST_IMG" "$offset_l2_bits" "\x1b"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+echo
+echo "== Invalid size =="
+_make_test_img 64M
+poke_file "$TEST_IMG" "$offset_size" "\xee\xee\xee\xee\xee\xee\xee\xee"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_size" "\x7f\xff\xff\xff\xff\xff\xff\xff"
+{ $QEMU_IO -c "write 0 64M" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+echo
+echo "== Invalid backing file length =="
+_make_test_img 64M
+poke_file "$TEST_IMG" "$offset_backing_file_offset" "\x00\x00\x00\xff"
+poke_file "$TEST_IMG" "$offset_backing_file_size" "\xff\xff\xff\xff"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+poke_file "$TEST_IMG" "$offset_backing_file_size" "\x7f\xff\xff\xff"
+{ $QEMU_IO -c "read 0 512" $TEST_IMG; } 2>&1 | _filter_qemu_io | _filter_testdir
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/092.out b/tests/qemu-iotests/092.out
new file mode 100644
index 0000000..496d8f0
--- /dev/null
+++ b/tests/qemu-iotests/092.out
@@ -0,0 +1,38 @@
+QA output created by 092
+
+== Invalid cluster size ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+qemu-io: can't open device TEST_DIR/t.qcow: Cluster size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: Cluster size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: Cluster size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: Cluster size must be between 512 and 64k
+no file open, try 'help open'
+
+== Invalid L2 table size ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 and 64k
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: L2 table size must be between 512 and 64k
+no file open, try 'help open'
+
+== Invalid size ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+qemu-io: can't open device TEST_DIR/t.qcow: Image too large
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: Image too large
+no file open, try 'help open'
+
+== Invalid backing file length ==
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 
+qemu-io: can't open device TEST_DIR/t.qcow: Backing file name too long
+no file open, try 'help open'
+qemu-io: can't open device TEST_DIR/t.qcow: Backing file name too long
+no file open, try 'help open'
+*** done
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index 776985d..a04df7f 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -150,6 +150,7 @@
 _filter_qemu_io()
 {
     _filter_win32 | sed -e "s/[0-9]* ops\; [0-9/:. sec]* ([0-9/.inf]* [EPTGMKiBbytes]*\/sec and [0-9/.inf]* ops\/sec)/X ops\; XX:XX:XX.X (XXX YYY\/sec and XXX ops\/sec)/" \
+        -e "s/: line [0-9][0-9]*:  *[0-9][0-9]*\( Aborted\)/:\1/" \
         -e "s/qemu-io> //g"
 }
 
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index cd3e4d2..0f07440 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -95,5 +95,7 @@
 086 rw auto quick
 087 rw auto
 088 rw auto
+089 rw auto quick
 090 rw auto quick
 091 rw auto
+092 rw auto quick
diff --git a/tests/qemu-iotests/sample_images/test-disk2vhd.vhdx.bz2 b/tests/qemu-iotests/sample_images/test-disk2vhd.vhdx.bz2
new file mode 100644
index 0000000..2891c9a
--- /dev/null
+++ b/tests/qemu-iotests/sample_images/test-disk2vhd.vhdx.bz2
Binary files differ
diff --git a/util/iov.c b/util/iov.c
index 6569b5a..49f8838 100644
--- a/util/iov.c
+++ b/util/iov.c
@@ -335,6 +335,27 @@
     qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes);
 }
 
+/*
+ * Check if the contents of the iovecs are all zero
+ */
+bool qemu_iovec_is_zero(QEMUIOVector *qiov)
+{
+    int i;
+    for (i = 0; i < qiov->niov; i++) {
+        size_t offs = QEMU_ALIGN_DOWN(qiov->iov[i].iov_len, 4 * sizeof(long));
+        uint8_t *ptr = qiov->iov[i].iov_base;
+        if (offs && !buffer_is_zero(qiov->iov[i].iov_base, offs)) {
+            return false;
+        }
+        for (; offs < qiov->iov[i].iov_len; offs++) {
+            if (ptr[offs]) {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
 void qemu_iovec_destroy(QEMUIOVector *qiov)
 {
     assert(qiov->nalloc != -1);