vmstate: Move VMState code to vmstate.c

This will allow unit tests to be written for VMState code without
pulling dependencies from the savevm code.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

3 files changed, 651 insertions, 645 deletions

diff --git a/Makefile.objs b/Makefile.objs
index 2b6c1fe2a8..23eda2b19b 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -51,6 +51,7 @@ common-obj-$(CONFIG_POSIX) += os-posix.o
 common-obj-$(CONFIG_LINUX) += fsdev/
 
 common-obj-y += migration.o migration-tcp.o
+common-obj-y += vmstate.o
 common-obj-$(CONFIG_RDMA) += migration-rdma.o
 common-obj-y += qemu-char.o #aio.o
 common-obj-y += block-migration.o
diff --git a/savevm.c b/savevm.c
index bdb90ef09b..3f13a6a4d2 100644
--- a/savevm.c
+++ b/savevm.c
@@ -38,7 +38,6 @@
 #include "exec/memory.h"
 #include "qmp-commands.h"
 #include "trace.h"
-#include "qemu/bitops.h"
 #include "qemu/iov.h"
 #include "block/snapshot.h"
 #include "block/qapi.h"
@@ -1010,344 +1009,6 @@ void timer_get(QEMUFile *f, QEMUTimer *ts)
 }
 
 
-/* bool */
-
-static int get_bool(QEMUFile *f, void *pv, size_t size)
-{
-    bool *v = pv;
-    *v = qemu_get_byte(f);
-    return 0;
-}
-
-static void put_bool(QEMUFile *f, void *pv, size_t size)
-{
-    bool *v = pv;
-    qemu_put_byte(f, *v);
-}
-
-const VMStateInfo vmstate_info_bool = {
-    .name = "bool",
-    .get  = get_bool,
-    .put  = put_bool,
-};
-
-/* 8 bit int */
-
-static int get_int8(QEMUFile *f, void *pv, size_t size)
-{
-    int8_t *v = pv;
-    qemu_get_s8s(f, v);
-    return 0;
-}
-
-static void put_int8(QEMUFile *f, void *pv, size_t size)
-{
-    int8_t *v = pv;
-    qemu_put_s8s(f, v);
-}
-
-const VMStateInfo vmstate_info_int8 = {
-    .name = "int8",
-    .get  = get_int8,
-    .put  = put_int8,
-};
-
-/* 16 bit int */
-
-static int get_int16(QEMUFile *f, void *pv, size_t size)
-{
-    int16_t *v = pv;
-    qemu_get_sbe16s(f, v);
-    return 0;
-}
-
-static void put_int16(QEMUFile *f, void *pv, size_t size)
-{
-    int16_t *v = pv;
-    qemu_put_sbe16s(f, v);
-}
-
-const VMStateInfo vmstate_info_int16 = {
-    .name = "int16",
-    .get  = get_int16,
-    .put  = put_int16,
-};
-
-/* 32 bit int */
-
-static int get_int32(QEMUFile *f, void *pv, size_t size)
-{
-    int32_t *v = pv;
-    qemu_get_sbe32s(f, v);
-    return 0;
-}
-
-static void put_int32(QEMUFile *f, void *pv, size_t size)
-{
-    int32_t *v = pv;
-    qemu_put_sbe32s(f, v);
-}
-
-const VMStateInfo vmstate_info_int32 = {
-    .name = "int32",
-    .get  = get_int32,
-    .put  = put_int32,
-};
-
-/* 32 bit int. See that the received value is the same than the one
-   in the field */
-
-static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
-{
-    int32_t *v = pv;
-    int32_t v2;
-    qemu_get_sbe32s(f, &v2);
-
-    if (*v == v2) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_int32_equal = {
-    .name = "int32 equal",
-    .get  = get_int32_equal,
-    .put  = put_int32,
-};
-
-/* 32 bit int. See that the received value is the less or the same
-   than the one in the field */
-
-static int get_int32_le(QEMUFile *f, void *pv, size_t size)
-{
-    int32_t *old = pv;
-    int32_t new;
-    qemu_get_sbe32s(f, &new);
-
-    if (*old <= new) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_int32_le = {
-    .name = "int32 equal",
-    .get  = get_int32_le,
-    .put  = put_int32,
-};
-
-/* 64 bit int */
-
-static int get_int64(QEMUFile *f, void *pv, size_t size)
-{
-    int64_t *v = pv;
-    qemu_get_sbe64s(f, v);
-    return 0;
-}
-
-static void put_int64(QEMUFile *f, void *pv, size_t size)
-{
-    int64_t *v = pv;
-    qemu_put_sbe64s(f, v);
-}
-
-const VMStateInfo vmstate_info_int64 = {
-    .name = "int64",
-    .get  = get_int64,
-    .put  = put_int64,
-};
-
-/* 8 bit unsigned int */
-
-static int get_uint8(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t *v = pv;
-    qemu_get_8s(f, v);
-    return 0;
-}
-
-static void put_uint8(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t *v = pv;
-    qemu_put_8s(f, v);
-}
-
-const VMStateInfo vmstate_info_uint8 = {
-    .name = "uint8",
-    .get  = get_uint8,
-    .put  = put_uint8,
-};
-
-/* 16 bit unsigned int */
-
-static int get_uint16(QEMUFile *f, void *pv, size_t size)
-{
-    uint16_t *v = pv;
-    qemu_get_be16s(f, v);
-    return 0;
-}
-
-static void put_uint16(QEMUFile *f, void *pv, size_t size)
-{
-    uint16_t *v = pv;
-    qemu_put_be16s(f, v);
-}
-
-const VMStateInfo vmstate_info_uint16 = {
-    .name = "uint16",
-    .get  = get_uint16,
-    .put  = put_uint16,
-};
-
-/* 32 bit unsigned int */
-
-static int get_uint32(QEMUFile *f, void *pv, size_t size)
-{
-    uint32_t *v = pv;
-    qemu_get_be32s(f, v);
-    return 0;
-}
-
-static void put_uint32(QEMUFile *f, void *pv, size_t size)
-{
-    uint32_t *v = pv;
-    qemu_put_be32s(f, v);
-}
-
-const VMStateInfo vmstate_info_uint32 = {
-    .name = "uint32",
-    .get  = get_uint32,
-    .put  = put_uint32,
-};
-
-/* 32 bit uint. See that the received value is the same than the one
-   in the field */
-
-static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
-{
-    uint32_t *v = pv;
-    uint32_t v2;
-    qemu_get_be32s(f, &v2);
-
-    if (*v == v2) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_uint32_equal = {
-    .name = "uint32 equal",
-    .get  = get_uint32_equal,
-    .put  = put_uint32,
-};
-
-/* 64 bit unsigned int */
-
-static int get_uint64(QEMUFile *f, void *pv, size_t size)
-{
-    uint64_t *v = pv;
-    qemu_get_be64s(f, v);
-    return 0;
-}
-
-static void put_uint64(QEMUFile *f, void *pv, size_t size)
-{
-    uint64_t *v = pv;
-    qemu_put_be64s(f, v);
-}
-
-const VMStateInfo vmstate_info_uint64 = {
-    .name = "uint64",
-    .get  = get_uint64,
-    .put  = put_uint64,
-};
-
-/* 64 bit unsigned int. See that the received value is the same than the one
-   in the field */
-
-static int get_uint64_equal(QEMUFile *f, void *pv, size_t size)
-{
-    uint64_t *v = pv;
-    uint64_t v2;
-    qemu_get_be64s(f, &v2);
-
-    if (*v == v2) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_uint64_equal = {
-    .name = "int64 equal",
-    .get  = get_uint64_equal,
-    .put  = put_uint64,
-};
-
-/* 8 bit int. See that the received value is the same than the one
-   in the field */
-
-static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t *v = pv;
-    uint8_t v2;
-    qemu_get_8s(f, &v2);
-
-    if (*v == v2) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_uint8_equal = {
-    .name = "uint8 equal",
-    .get  = get_uint8_equal,
-    .put  = put_uint8,
-};
-
-/* 16 bit unsigned int int. See that the received value is the same than the one
-   in the field */
-
-static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
-{
-    uint16_t *v = pv;
-    uint16_t v2;
-    qemu_get_be16s(f, &v2);
-
-    if (*v == v2) {
-        return 0;
-    }
-    return -EINVAL;
-}
-
-const VMStateInfo vmstate_info_uint16_equal = {
-    .name = "uint16 equal",
-    .get  = get_uint16_equal,
-    .put  = put_uint16,
-};
-
-/* floating point */
-
-static int get_float64(QEMUFile *f, void *pv, size_t size)
-{
-    float64 *v = pv;
-
-    *v = make_float64(qemu_get_be64(f));
-    return 0;
-}
-
-static void put_float64(QEMUFile *f, void *pv, size_t size)
-{
-    uint64_t *v = pv;
-
-    qemu_put_be64(f, float64_val(*v));
-}
-
-const VMStateInfo vmstate_info_float64 = {
-    .name = "float64",
-    .get  = get_float64,
-    .put  = put_float64,
-};
-
 /* timers  */
 
 static int get_timer(QEMUFile *f, void *pv, size_t size)
@@ -1369,100 +1030,6 @@ const VMStateInfo vmstate_info_timer = {
     .put  = put_timer,
 };
 
-/* uint8_t buffers */
-
-static int get_buffer(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t *v = pv;
-    qemu_get_buffer(f, v, size);
-    return 0;
-}
-
-static void put_buffer(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t *v = pv;
-    qemu_put_buffer(f, v, size);
-}
-
-const VMStateInfo vmstate_info_buffer = {
-    .name = "buffer",
-    .get  = get_buffer,
-    .put  = put_buffer,
-};
-
-/* unused buffers: space that was used for some fields that are
-   not useful anymore */
-
-static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
-{
-    uint8_t buf[1024];
-    int block_len;
-
-    while (size > 0) {
-        block_len = MIN(sizeof(buf), size);
-        size -= block_len;
-        qemu_get_buffer(f, buf, block_len);
-    }
-   return 0;
-}
-
-static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
-{
-    static const uint8_t buf[1024];
-    int block_len;
-
-    while (size > 0) {
-        block_len = MIN(sizeof(buf), size);
-        size -= block_len;
-        qemu_put_buffer(f, buf, block_len);
-    }
-}
-
-const VMStateInfo vmstate_info_unused_buffer = {
-    .name = "unused_buffer",
-    .get  = get_unused_buffer,
-    .put  = put_unused_buffer,
-};
-
-/* bitmaps (as defined by bitmap.h). Note that size here is the size
- * of the bitmap in bits. The on-the-wire format of a bitmap is 64
- * bit words with the bits in big endian order. The in-memory format
- * is an array of 'unsigned long', which may be either 32 or 64 bits.
- */
-/* This is the number of 64 bit words sent over the wire */
-#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, 64)
-static int get_bitmap(QEMUFile *f, void *pv, size_t size)
-{
-    unsigned long *bmp = pv;
-    int i, idx = 0;
-    for (i = 0; i < BITS_TO_U64S(size); i++) {
-        uint64_t w = qemu_get_be64(f);
-        bmp[idx++] = w;
-        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
-            bmp[idx++] = w >> 32;
-        }
-    }
-    return 0;
-}
-
-static void put_bitmap(QEMUFile *f, void *pv, size_t size)
-{
-    unsigned long *bmp = pv;
-    int i, idx = 0;
-    for (i = 0; i < BITS_TO_U64S(size); i++) {
-        uint64_t w = bmp[idx++];
-        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
-            w |= ((uint64_t)bmp[idx++]) << 32;
-        }
-        qemu_put_be64(f, w);
-    }
-}
-
-const VMStateInfo vmstate_info_bitmap = {
-    .name = "bitmap",
-    .get = get_bitmap,
-    .put = put_bitmap,
-};
 
 typedef struct CompatEntry {
     char idstr[256];
@@ -1676,144 +1243,6 @@ void vmstate_unregister(DeviceState *dev, const VMStateDescription *vmsd,
     }
 }
 
-static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
-                                    void *opaque);
-static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
-                                   void *opaque);
-
-int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
-                       void *opaque, int version_id)
-{
-    VMStateField *field = vmsd->fields;
-    int ret;
-
-    if (version_id > vmsd->version_id) {
-        return -EINVAL;
-    }
-    if (version_id < vmsd->minimum_version_id_old) {
-        return -EINVAL;
-    }
-    if  (version_id < vmsd->minimum_version_id) {
-        return vmsd->load_state_old(f, opaque, version_id);
-    }
-    if (vmsd->pre_load) {
-        int ret = vmsd->pre_load(opaque);
-        if (ret) {
-            return ret;
-        }
-    }
-    while (field->name) {
-        if ((field->field_exists &&
-             field->field_exists(opaque, version_id)) ||
-            (!field->field_exists &&
-             field->version_id <= version_id)) {
-            void *base_addr = opaque + field->offset;
-            int i, n_elems = 1;
-            int size = field->size;
-
-            if (field->flags & VMS_VBUFFER) {
-                size = *(int32_t *)(opaque+field->size_offset);
-                if (field->flags & VMS_MULTIPLY) {
-                    size *= field->size;
-                }
-            }
-            if (field->flags & VMS_ARRAY) {
-                n_elems = field->num;
-            } else if (field->flags & VMS_VARRAY_INT32) {
-                n_elems = *(int32_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT32) {
-                n_elems = *(uint32_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT16) {
-                n_elems = *(uint16_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT8) {
-                n_elems = *(uint8_t *)(opaque+field->num_offset);
-            }
-            if (field->flags & VMS_POINTER) {
-                base_addr = *(void **)base_addr + field->start;
-            }
-            for (i = 0; i < n_elems; i++) {
-                void *addr = base_addr + size * i;
-
-                if (field->flags & VMS_ARRAY_OF_POINTER) {
-                    addr = *(void **)addr;
-                }
-                if (field->flags & VMS_STRUCT) {
-                    ret = vmstate_load_state(f, field->vmsd, addr,
-                                             field->vmsd->version_id);
-                } else {
-                    ret = field->info->get(f, addr, size);
-
-                }
-                if (ret < 0) {
-                    return ret;
-                }
-            }
-        }
-        field++;
-    }
-    ret = vmstate_subsection_load(f, vmsd, opaque);
-    if (ret != 0) {
-        return ret;
-    }
-    if (vmsd->post_load) {
-        return vmsd->post_load(opaque, version_id);
-    }
-    return 0;
-}
-
-void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
-                        void *opaque)
-{
-    VMStateField *field = vmsd->fields;
-
-    if (vmsd->pre_save) {
-        vmsd->pre_save(opaque);
-    }
-    while (field->name) {
-        if (!field->field_exists ||
-            field->field_exists(opaque, vmsd->version_id)) {
-            void *base_addr = opaque + field->offset;
-            int i, n_elems = 1;
-            int size = field->size;
-
-            if (field->flags & VMS_VBUFFER) {
-                size = *(int32_t *)(opaque+field->size_offset);
-                if (field->flags & VMS_MULTIPLY) {
-                    size *= field->size;
-                }
-            }
-            if (field->flags & VMS_ARRAY) {
-                n_elems = field->num;
-            } else if (field->flags & VMS_VARRAY_INT32) {
-                n_elems = *(int32_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT32) {
-                n_elems = *(uint32_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT16) {
-                n_elems = *(uint16_t *)(opaque+field->num_offset);
-            } else if (field->flags & VMS_VARRAY_UINT8) {
-                n_elems = *(uint8_t *)(opaque+field->num_offset);
-            }
-            if (field->flags & VMS_POINTER) {
-                base_addr = *(void **)base_addr + field->start;
-            }
-            for (i = 0; i < n_elems; i++) {
-                void *addr = base_addr + size * i;
-
-                if (field->flags & VMS_ARRAY_OF_POINTER) {
-                    addr = *(void **)addr;
-                }
-                if (field->flags & VMS_STRUCT) {
-                    vmstate_save_state(f, field->vmsd, addr);
-                } else {
-                    field->info->put(f, addr, size);
-                }
-            }
-        }
-        field++;
-    }
-    vmstate_subsection_save(f, vmsd, opaque);
-}
-
 static int vmstate_load(QEMUFile *f, SaveStateEntry *se, int version_id)
 {
     if (!se->vmsd) {         /* Old style */
@@ -2114,80 +1543,6 @@ static SaveStateEntry *find_se(const char *idstr, int instance_id)
     return NULL;
 }
 
-static const VMStateDescription *
-    vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
-{
-    while (sub && sub->needed) {
-        if (strcmp(idstr, sub->vmsd->name) == 0) {
-            return sub->vmsd;
-        }
-        sub++;
-    }
-    return NULL;
-}
-
-static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
-                                   void *opaque)
-{
-    while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
-        char idstr[256];
-        int ret;
-        uint8_t version_id, len, size;
-        const VMStateDescription *sub_vmsd;
-
-        len = qemu_peek_byte(f, 1);
-        if (len < strlen(vmsd->name) + 1) {
-            /* subsection name has be be "section_name/a" */
-            return 0;
-        }
-        size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
-        if (size != len) {
-            return 0;
-        }
-        idstr[size] = 0;
-
-        if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
-            /* it don't have a valid subsection name */
-            return 0;
-        }
-        sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
-        if (sub_vmsd == NULL) {
-            return -ENOENT;
-        }
-        qemu_file_skip(f, 1); /* subsection */
-        qemu_file_skip(f, 1); /* len */
-        qemu_file_skip(f, len); /* idstr */
-        version_id = qemu_get_be32(f);
-
-        ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
-        if (ret) {
-            return ret;
-        }
-    }
-    return 0;
-}
-
-static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
-                                    void *opaque)
-{
-    const VMStateSubsection *sub = vmsd->subsections;
-
-    while (sub && sub->needed) {
-        if (sub->needed(opaque)) {
-            const VMStateDescription *vmsd = sub->vmsd;
-            uint8_t len;
-
-            qemu_put_byte(f, QEMU_VM_SUBSECTION);
-            len = strlen(vmsd->name);
-            qemu_put_byte(f, len);
-            qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
-            qemu_put_be32(f, vmsd->version_id);
-            vmstate_save_state(f, vmsd, opaque);
-        }
-        sub++;
-    }
-}
-
 typedef struct LoadStateEntry {
     QLIST_ENTRY(LoadStateEntry) entry;
     SaveStateEntry *se;
diff --git a/vmstate.c b/vmstate.c
new file mode 100644
index 0000000000..284b080f46
--- /dev/null
+++ b/vmstate.c
@@ -0,0 +1,650 @@
+#include "qemu-common.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "migration/vmstate.h"
+#include "qemu/bitops.h"
+
+static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
+                                    void *opaque);
+static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
+                                   void *opaque);
+
+int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
+                       void *opaque, int version_id)
+{
+    VMStateField *field = vmsd->fields;
+    int ret;
+
+    if (version_id > vmsd->version_id) {
+        return -EINVAL;
+    }
+    if (version_id < vmsd->minimum_version_id_old) {
+        return -EINVAL;
+    }
+    if  (version_id < vmsd->minimum_version_id) {
+        return vmsd->load_state_old(f, opaque, version_id);
+    }
+    if (vmsd->pre_load) {
+        int ret = vmsd->pre_load(opaque);
+        if (ret) {
+            return ret;
+        }
+    }
+    while (field->name) {
+        if ((field->field_exists &&
+             field->field_exists(opaque, version_id)) ||
+            (!field->field_exists &&
+             field->version_id <= version_id)) {
+            void *base_addr = opaque + field->offset;
+            int i, n_elems = 1;
+            int size = field->size;
+
+            if (field->flags & VMS_VBUFFER) {
+                size = *(int32_t *)(opaque+field->size_offset);
+                if (field->flags & VMS_MULTIPLY) {
+                    size *= field->size;
+                }
+            }
+            if (field->flags & VMS_ARRAY) {
+                n_elems = field->num;
+            } else if (field->flags & VMS_VARRAY_INT32) {
+                n_elems = *(int32_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT32) {
+                n_elems = *(uint32_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT16) {
+                n_elems = *(uint16_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT8) {
+                n_elems = *(uint8_t *)(opaque+field->num_offset);
+            }
+            if (field->flags & VMS_POINTER) {
+                base_addr = *(void **)base_addr + field->start;
+            }
+            for (i = 0; i < n_elems; i++) {
+                void *addr = base_addr + size * i;
+
+                if (field->flags & VMS_ARRAY_OF_POINTER) {
+                    addr = *(void **)addr;
+                }
+                if (field->flags & VMS_STRUCT) {
+                    ret = vmstate_load_state(f, field->vmsd, addr,
+                                             field->vmsd->version_id);
+                } else {
+                    ret = field->info->get(f, addr, size);
+
+                }
+                if (ret < 0) {
+                    return ret;
+                }
+            }
+        }
+        field++;
+    }
+    ret = vmstate_subsection_load(f, vmsd, opaque);
+    if (ret != 0) {
+        return ret;
+    }
+    if (vmsd->post_load) {
+        return vmsd->post_load(opaque, version_id);
+    }
+    return 0;
+}
+
+void vmstate_save_state(QEMUFile *f, const VMStateDescription *vmsd,
+                        void *opaque)
+{
+    VMStateField *field = vmsd->fields;
+
+    if (vmsd->pre_save) {
+        vmsd->pre_save(opaque);
+    }
+    while (field->name) {
+        if (!field->field_exists ||
+            field->field_exists(opaque, vmsd->version_id)) {
+            void *base_addr = opaque + field->offset;
+            int i, n_elems = 1;
+            int size = field->size;
+
+            if (field->flags & VMS_VBUFFER) {
+                size = *(int32_t *)(opaque+field->size_offset);
+                if (field->flags & VMS_MULTIPLY) {
+                    size *= field->size;
+                }
+            }
+            if (field->flags & VMS_ARRAY) {
+                n_elems = field->num;
+            } else if (field->flags & VMS_VARRAY_INT32) {
+                n_elems = *(int32_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT32) {
+                n_elems = *(uint32_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT16) {
+                n_elems = *(uint16_t *)(opaque+field->num_offset);
+            } else if (field->flags & VMS_VARRAY_UINT8) {
+                n_elems = *(uint8_t *)(opaque+field->num_offset);
+            }
+            if (field->flags & VMS_POINTER) {
+                base_addr = *(void **)base_addr + field->start;
+            }
+            for (i = 0; i < n_elems; i++) {
+                void *addr = base_addr + size * i;
+
+                if (field->flags & VMS_ARRAY_OF_POINTER) {
+                    addr = *(void **)addr;
+                }
+                if (field->flags & VMS_STRUCT) {
+                    vmstate_save_state(f, field->vmsd, addr);
+                } else {
+                    field->info->put(f, addr, size);
+                }
+            }
+        }
+        field++;
+    }
+    vmstate_subsection_save(f, vmsd, opaque);
+}
+
+static const VMStateDescription *
+    vmstate_get_subsection(const VMStateSubsection *sub, char *idstr)
+{
+    while (sub && sub->needed) {
+        if (strcmp(idstr, sub->vmsd->name) == 0) {
+            return sub->vmsd;
+        }
+        sub++;
+    }
+    return NULL;
+}
+
+static int vmstate_subsection_load(QEMUFile *f, const VMStateDescription *vmsd,
+                                   void *opaque)
+{
+    while (qemu_peek_byte(f, 0) == QEMU_VM_SUBSECTION) {
+        char idstr[256];
+        int ret;
+        uint8_t version_id, len, size;
+        const VMStateDescription *sub_vmsd;
+
+        len = qemu_peek_byte(f, 1);
+        if (len < strlen(vmsd->name) + 1) {
+            /* subsection name has be be "section_name/a" */
+            return 0;
+        }
+        size = qemu_peek_buffer(f, (uint8_t *)idstr, len, 2);
+        if (size != len) {
+            return 0;
+        }
+        idstr[size] = 0;
+
+        if (strncmp(vmsd->name, idstr, strlen(vmsd->name)) != 0) {
+            /* it don't have a valid subsection name */
+            return 0;
+        }
+        sub_vmsd = vmstate_get_subsection(vmsd->subsections, idstr);
+        if (sub_vmsd == NULL) {
+            return -ENOENT;
+        }
+        qemu_file_skip(f, 1); /* subsection */
+        qemu_file_skip(f, 1); /* len */
+        qemu_file_skip(f, len); /* idstr */
+        version_id = qemu_get_be32(f);
+
+        ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);
+        if (ret) {
+            return ret;
+        }
+    }
+    return 0;
+}
+
+static void vmstate_subsection_save(QEMUFile *f, const VMStateDescription *vmsd,
+                                    void *opaque)
+{
+    const VMStateSubsection *sub = vmsd->subsections;
+
+    while (sub && sub->needed) {
+        if (sub->needed(opaque)) {
+            const VMStateDescription *vmsd = sub->vmsd;
+            uint8_t len;
+
+            qemu_put_byte(f, QEMU_VM_SUBSECTION);
+            len = strlen(vmsd->name);
+            qemu_put_byte(f, len);
+            qemu_put_buffer(f, (uint8_t *)vmsd->name, len);
+            qemu_put_be32(f, vmsd->version_id);
+            vmstate_save_state(f, vmsd, opaque);
+        }
+        sub++;
+    }
+}
+
+/* bool */
+
+static int get_bool(QEMUFile *f, void *pv, size_t size)
+{
+    bool *v = pv;
+    *v = qemu_get_byte(f);
+    return 0;
+}
+
+static void put_bool(QEMUFile *f, void *pv, size_t size)
+{
+    bool *v = pv;
+    qemu_put_byte(f, *v);
+}
+
+const VMStateInfo vmstate_info_bool = {
+    .name = "bool",
+    .get  = get_bool,
+    .put  = put_bool,
+};
+
+/* 8 bit int */
+
+static int get_int8(QEMUFile *f, void *pv, size_t size)
+{
+    int8_t *v = pv;
+    qemu_get_s8s(f, v);
+    return 0;
+}
+
+static void put_int8(QEMUFile *f, void *pv, size_t size)
+{
+    int8_t *v = pv;
+    qemu_put_s8s(f, v);
+}
+
+const VMStateInfo vmstate_info_int8 = {
+    .name = "int8",
+    .get  = get_int8,
+    .put  = put_int8,
+};
+
+/* 16 bit int */
+
+static int get_int16(QEMUFile *f, void *pv, size_t size)
+{
+    int16_t *v = pv;
+    qemu_get_sbe16s(f, v);
+    return 0;
+}
+
+static void put_int16(QEMUFile *f, void *pv, size_t size)
+{
+    int16_t *v = pv;
+    qemu_put_sbe16s(f, v);
+}
+
+const VMStateInfo vmstate_info_int16 = {
+    .name = "int16",
+    .get  = get_int16,
+    .put  = put_int16,
+};
+
+/* 32 bit int */
+
+static int get_int32(QEMUFile *f, void *pv, size_t size)
+{
+    int32_t *v = pv;
+    qemu_get_sbe32s(f, v);
+    return 0;
+}
+
+static void put_int32(QEMUFile *f, void *pv, size_t size)
+{
+    int32_t *v = pv;
+    qemu_put_sbe32s(f, v);
+}
+
+const VMStateInfo vmstate_info_int32 = {
+    .name = "int32",
+    .get  = get_int32,
+    .put  = put_int32,
+};
+
+/* 32 bit int. See that the received value is the same than the one
+   in the field */
+
+static int get_int32_equal(QEMUFile *f, void *pv, size_t size)
+{
+    int32_t *v = pv;
+    int32_t v2;
+    qemu_get_sbe32s(f, &v2);
+
+    if (*v == v2) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_int32_equal = {
+    .name = "int32 equal",
+    .get  = get_int32_equal,
+    .put  = put_int32,
+};
+
+/* 32 bit int. See that the received value is the less or the same
+   than the one in the field */
+
+static int get_int32_le(QEMUFile *f, void *pv, size_t size)
+{
+    int32_t *old = pv;
+    int32_t new;
+    qemu_get_sbe32s(f, &new);
+
+    if (*old <= new) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_int32_le = {
+    .name = "int32 equal",
+    .get  = get_int32_le,
+    .put  = put_int32,
+};
+
+/* 64 bit int */
+
+static int get_int64(QEMUFile *f, void *pv, size_t size)
+{
+    int64_t *v = pv;
+    qemu_get_sbe64s(f, v);
+    return 0;
+}
+
+static void put_int64(QEMUFile *f, void *pv, size_t size)
+{
+    int64_t *v = pv;
+    qemu_put_sbe64s(f, v);
+}
+
+const VMStateInfo vmstate_info_int64 = {
+    .name = "int64",
+    .get  = get_int64,
+    .put  = put_int64,
+};
+
+/* 8 bit unsigned int */
+
+static int get_uint8(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    qemu_get_8s(f, v);
+    return 0;
+}
+
+static void put_uint8(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    qemu_put_8s(f, v);
+}
+
+const VMStateInfo vmstate_info_uint8 = {
+    .name = "uint8",
+    .get  = get_uint8,
+    .put  = put_uint8,
+};
+
+/* 16 bit unsigned int */
+
+static int get_uint16(QEMUFile *f, void *pv, size_t size)
+{
+    uint16_t *v = pv;
+    qemu_get_be16s(f, v);
+    return 0;
+}
+
+static void put_uint16(QEMUFile *f, void *pv, size_t size)
+{
+    uint16_t *v = pv;
+    qemu_put_be16s(f, v);
+}
+
+const VMStateInfo vmstate_info_uint16 = {
+    .name = "uint16",
+    .get  = get_uint16,
+    .put  = put_uint16,
+};
+
+/* 32 bit unsigned int */
+
+static int get_uint32(QEMUFile *f, void *pv, size_t size)
+{
+    uint32_t *v = pv;
+    qemu_get_be32s(f, v);
+    return 0;
+}
+
+static void put_uint32(QEMUFile *f, void *pv, size_t size)
+{
+    uint32_t *v = pv;
+    qemu_put_be32s(f, v);
+}
+
+const VMStateInfo vmstate_info_uint32 = {
+    .name = "uint32",
+    .get  = get_uint32,
+    .put  = put_uint32,
+};
+
+/* 32 bit uint. See that the received value is the same than the one
+   in the field */
+
+static int get_uint32_equal(QEMUFile *f, void *pv, size_t size)
+{
+    uint32_t *v = pv;
+    uint32_t v2;
+    qemu_get_be32s(f, &v2);
+
+    if (*v == v2) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_uint32_equal = {
+    .name = "uint32 equal",
+    .get  = get_uint32_equal,
+    .put  = put_uint32,
+};
+
+/* 64 bit unsigned int */
+
+static int get_uint64(QEMUFile *f, void *pv, size_t size)
+{
+    uint64_t *v = pv;
+    qemu_get_be64s(f, v);
+    return 0;
+}
+
+static void put_uint64(QEMUFile *f, void *pv, size_t size)
+{
+    uint64_t *v = pv;
+    qemu_put_be64s(f, v);
+}
+
+const VMStateInfo vmstate_info_uint64 = {
+    .name = "uint64",
+    .get  = get_uint64,
+    .put  = put_uint64,
+};
+
+/* 64 bit unsigned int. See that the received value is the same than the one
+   in the field */
+
+static int get_uint64_equal(QEMUFile *f, void *pv, size_t size)
+{
+    uint64_t *v = pv;
+    uint64_t v2;
+    qemu_get_be64s(f, &v2);
+
+    if (*v == v2) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_uint64_equal = {
+    .name = "int64 equal",
+    .get  = get_uint64_equal,
+    .put  = put_uint64,
+};
+
+/* 8 bit int. See that the received value is the same than the one
+   in the field */
+
+static int get_uint8_equal(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    uint8_t v2;
+    qemu_get_8s(f, &v2);
+
+    if (*v == v2) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_uint8_equal = {
+    .name = "uint8 equal",
+    .get  = get_uint8_equal,
+    .put  = put_uint8,
+};
+
+/* 16 bit unsigned int int. See that the received value is the same than the one
+   in the field */
+
+static int get_uint16_equal(QEMUFile *f, void *pv, size_t size)
+{
+    uint16_t *v = pv;
+    uint16_t v2;
+    qemu_get_be16s(f, &v2);
+
+    if (*v == v2) {
+        return 0;
+    }
+    return -EINVAL;
+}
+
+const VMStateInfo vmstate_info_uint16_equal = {
+    .name = "uint16 equal",
+    .get  = get_uint16_equal,
+    .put  = put_uint16,
+};
+
+/* floating point */
+
+static int get_float64(QEMUFile *f, void *pv, size_t size)
+{
+    float64 *v = pv;
+
+    *v = make_float64(qemu_get_be64(f));
+    return 0;
+}
+
+static void put_float64(QEMUFile *f, void *pv, size_t size)
+{
+    uint64_t *v = pv;
+
+    qemu_put_be64(f, float64_val(*v));
+}
+
+const VMStateInfo vmstate_info_float64 = {
+    .name = "float64",
+    .get  = get_float64,
+    .put  = put_float64,
+};
+
+/* uint8_t buffers */
+
+static int get_buffer(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    qemu_get_buffer(f, v, size);
+    return 0;
+}
+
+static void put_buffer(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t *v = pv;
+    qemu_put_buffer(f, v, size);
+}
+
+const VMStateInfo vmstate_info_buffer = {
+    .name = "buffer",
+    .get  = get_buffer,
+    .put  = put_buffer,
+};
+
+/* unused buffers: space that was used for some fields that are
+   not useful anymore */
+
+static int get_unused_buffer(QEMUFile *f, void *pv, size_t size)
+{
+    uint8_t buf[1024];
+    int block_len;
+
+    while (size > 0) {
+        block_len = MIN(sizeof(buf), size);
+        size -= block_len;
+        qemu_get_buffer(f, buf, block_len);
+    }
+   return 0;
+}
+
+static void put_unused_buffer(QEMUFile *f, void *pv, size_t size)
+{
+    static const uint8_t buf[1024];
+    int block_len;
+
+    while (size > 0) {
+        block_len = MIN(sizeof(buf), size);
+        size -= block_len;
+        qemu_put_buffer(f, buf, block_len);
+    }
+}
+
+const VMStateInfo vmstate_info_unused_buffer = {
+    .name = "unused_buffer",
+    .get  = get_unused_buffer,
+    .put  = put_unused_buffer,
+};
+
+/* bitmaps (as defined by bitmap.h). Note that size here is the size
+ * of the bitmap in bits. The on-the-wire format of a bitmap is 64
+ * bit words with the bits in big endian order. The in-memory format
+ * is an array of 'unsigned long', which may be either 32 or 64 bits.
+ */
+/* This is the number of 64 bit words sent over the wire */
+#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, 64)
+static int get_bitmap(QEMUFile *f, void *pv, size_t size)
+{
+    unsigned long *bmp = pv;
+    int i, idx = 0;
+    for (i = 0; i < BITS_TO_U64S(size); i++) {
+        uint64_t w = qemu_get_be64(f);
+        bmp[idx++] = w;
+        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
+            bmp[idx++] = w >> 32;
+        }
+    }
+    return 0;
+}
+
+static void put_bitmap(QEMUFile *f, void *pv, size_t size)
+{
+    unsigned long *bmp = pv;
+    int i, idx = 0;
+    for (i = 0; i < BITS_TO_U64S(size); i++) {
+        uint64_t w = bmp[idx++];
+        if (sizeof(unsigned long) == 4 && idx < BITS_TO_LONGS(size)) {
+            w |= ((uint64_t)bmp[idx++]) << 32;
+        }
+        qemu_put_be64(f, w);
+    }
+}
+
+const VMStateInfo vmstate_info_bitmap = {
+    .name = "bitmap",
+    .get = get_bitmap,
+    .put = put_bitmap,
+};