diff --git a/libqblock/libqblock-internal.h b/libqblock/libqblock-internal.h
new file mode 100644
index 0000000..fa27ed4
--- /dev/null
+++ b/libqblock/libqblock-internal.h
@@ -0,0 +1,50 @@
+/*
+ * QEMU block layer library
+ *
+ * Copyright IBM, Corp. 2012
+ *
+ * Authors:
+ *  Wenchao Xia   <xiawenc@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#ifndef LIBQBLOCK_INTERNAL
+#define LIBQBLOCK_INTERNAL
+
+#include "block.h"
+#include "block_int.h"
+
+#include "libqblock-types.h"
+
+/* this file contains defines and types used inside the library. */
+
+#define FUNC_FREE free
+#define FUNC_MALLOC malloc
+#define FUNC_CALLOC calloc
+
+#define CLEAN_FREE(p) { \
+        FUNC_FREE(p); \
+        (p) = NULL; \
+}
+
+/* details should be hidden to user */
+struct QBlockState {
+    BlockDriverState *bdrvs;
+    /* internal used file name now, if it is not NULL, it means
+       image was opened.
+    */
+    char *filename;
+};
+
+#define QB_ERR_STRING_SIZE (1024)
+struct QBroker {
+    /* last error */
+    char err_msg[QB_ERR_STRING_SIZE];
+    int err_ret; /* last error return of libqblock. */
+    int err_no; /* 2nd level of error, errno what below reports */
+};
+
+#endif
diff --git a/libqblock/libqblock-types.h b/libqblock/libqblock-types.h
new file mode 100644
index 0000000..9d4e3fc
--- /dev/null
+++ b/libqblock/libqblock-types.h
@@ -0,0 +1,251 @@
+/*
+ * QEMU block layer library
+ *
+ * Copyright IBM, Corp. 2012
+ *
+ * Authors:
+ *  Wenchao Xia   <xiawenc@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#ifndef LIBQBLOCK_TYPES_H
+#define LIBQBLOCK_TYPES_H
+
+#include <sys/types.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#if __GNUC__ >= 4
+    #ifdef LIBQB_BUILD
+        #define DLL_PUBLIC __attribute__((visibility("default")))
+    #else
+        #define DLL_PUBLIC
+    #endif
+#endif
+
+/* this library is designed around this core struct. */
+struct QBlockState;
+
+/* every thread would have a broker. */
+struct QBroker;
+
+/* flag used in open and create */
+#define LIBQBLOCK_O_RDWR        0x0002
+/* do not use the host page cache */
+#define LIBQBLOCK_O_NOCACHE     0x0020
+/* use write-back caching */
+#define LIBQBLOCK_O_CACHE_WB    0x0040
+/* don't open the backing file */
+#define LIBQBLOCK_O_NO_BACKING  0x0100
+/* disable flushing on this disk */
+#define LIBQBLOCK_O_NO_FLUSH    0x0200
+
+#define LIBQBLOCK_O_CACHE_MASK \
+   (LIBQBLOCK_O_NOCACHE | LIBQBLOCK_O_CACHE_WB | LIBQBLOCK_O_NO_FLUSH)
+
+#define LIBQBLOCK_O_VALID_MASK \
+   (LIBQBLOCK_O_RDWR | LIBQBLOCK_O_NOCACHE | LIBQBLOCK_O_CACHE_WB | \
+    LIBQBLOCK_O_NO_BACKING | LIBQBLOCK_O_NO_FLUSH)
+
+enum QBlockProtType {
+    QB_PROT_NONE = 0,
+    QB_PROT_FILE,
+    QB_PROT_MAX
+};
+
+struct QBlockProtOptionFile {
+    const char *filename;
+};
+
+#define QBLOCK_PROT_OPTIONS_UNION_SIZE (512)
+union QBlockProtOptionsUnion {
+    struct QBlockProtOptionFile o_file;
+    uint8_t reserved[QBLOCK_PROT_OPTIONS_UNION_SIZE];
+};
+
+/**
+ * struct QBlockProtInfo: contains information about how to find the image
+ *
+ * @prot_type: protocol type, now only support FILE.
+ * @prot_op: protocol related options.
+ */
+struct QBlockProtInfo {
+    enum QBlockProtType prot_type;
+    union QBlockProtOptionsUnion prot_op;
+};
+
+
+/* format related options */
+enum QBlockFmtType {
+    QB_FMT_NONE = 0,
+    QB_FMT_COW,
+    QB_FMT_QED,
+    QB_FMT_QCOW,
+    QB_FMT_QCOW2,
+    QB_FMT_RAW,
+    QB_FMT_RBD,
+    QB_FMT_SHEEPDOG,
+    QB_FMT_VDI,
+    QB_FMT_VMDK,
+    QB_FMT_VPC,
+    QB_FMT_MAX
+};
+
+struct QBlockFmtOptionCow {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+};
+
+struct QBlockFmtOptionQed {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+    enum QBlockFmtType backing_fmt;
+    uint64_t cluster_size; /* unit is bytes */
+    uint64_t table_size; /* unit is clusters */
+};
+
+struct QBlockFmtOptionQcow {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+    bool encrypt;
+};
+
+/* "Compatibility level (0.10 or 1.1)" */
+enum QBlockFmtOptionQcow2CptLv {
+    QBO_FMT_QCOW2_CPT_NONE = 0,
+    QBO_FMT_QCOW2_CPT_V010,
+    QBO_FMT_QCOW2_CPT_V110,
+};
+
+/* off or metadata */
+enum QBlockFmtOptionQcow2PreAllocType {
+    QBO_FMT_QCOW2_PREALLOC_NONE = 0,
+    QBO_FMT_QCOW2_PREALLOC_OFF,
+    QBO_FMT_QCOW2_PREALLOC_METADATA,
+};
+
+struct QBlockFmtOptionQcow2 {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+    enum QBlockFmtType backing_fmt;
+    bool encrypt;
+    uint64_t cluster_size; /* unit is bytes */
+    enum QBlockFmtOptionQcow2CptLv cpt_lv;
+    enum QBlockFmtOptionQcow2PreAllocType pre_mode;
+};
+
+struct QBlockFmtOptionRaw {
+    uint64_t virt_size;
+};
+
+struct QBlockFmtOptionRbd {
+    uint64_t virt_size;
+    uint64_t cluster_size;
+};
+
+/* off or full */
+enum QBlockFmtOptionSheepdogPreAllocType {
+    QBO_FMT_SD_PREALLOC_NONE = 0,
+    QBO_FMT_SD_PREALLOC_OFF,
+    QBO_FMT_SD_PREALLOC_FULL,
+};
+
+struct QBlockFmtOptionSheepdog {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+    enum QBlockFmtOptionSheepdogPreAllocType pre_mode;
+};
+
+enum QBlockFmtOptionVdiPreAllocType {
+    QBO_FMT_VDI_PREALLOC_NONE = 0,
+    QBO_FMT_VDI_PREALLOC_FALSE,
+    QBO_FMT_VDI_PREALLOC_TRUE,
+};
+
+struct QBlockFmtOptionVdi {
+    uint64_t virt_size;
+    uint64_t cluster_size;
+    enum QBlockFmtOptionVdiPreAllocType pre_mode;
+};
+
+/* whether compact to vmdk verion 6 */
+enum QBlockFmtOptionVmdkCptLv {
+    QBO_FMT_VMDK_CPT_NONE = 0,
+    QBO_FMT_VMDK_CPT_VMDKV6_FALSE,
+    QBO_FMT_VMDK_CPT_VMDKV6_TRUE,
+};
+
+/* vmdk flat extent format, values:
+"{monolithicSparse (default) | monolithicFlat | twoGbMaxExtentSparse |
+twoGbMaxExtentFlat | streamOptimized} */
+enum QBlockFmtOptionVmdkSubfmtType {
+    QBO_FMT_VMDK_SUBFMT_MONOLITHIC_NONE = 0,
+    QBO_FMT_VMDK_SUBFMT_MONOLITHIC_SPARSE,
+    QBO_FMT_VMDK_SUBFMT_MONOLITHIC_FLAT,
+    QBO_FMT_VMDK_SUBFMT_TWOGBMAX_EXTENT_SPARSE,
+    QBO_FMT_VMDK_SUBFMT_TWOGBMAX_EXTENT_FLAT,
+    QBO_FMT_VMDK_SUBFMT_STREAM_OPTIMIZED,
+};
+
+struct QBlockFmtOptionVmdk {
+    uint64_t virt_size;
+    struct QBlockProtInfo backing_loc;
+    enum QBlockFmtOptionVmdkCptLv cpt_lv;
+    enum QBlockFmtOptionVmdkSubfmtType subfmt;
+};
+
+/* "{dynamic (default) | fixed} " */
+enum QBlockFmtOptionVpcSubfmtType {
+    QBO_FMT_VPC_SUBFMT_NONE = 0,
+    QBO_FMT_VPC_SUBFMT_DYNAMIC,
+    QBO_FMT_VPC_SUBFMT_FIXED,
+};
+
+struct QBlockFmtOptionVpc {
+    uint64_t virt_size;
+    enum QBlockFmtOptionVpcSubfmtType subfmt;
+};
+
+#define QBLOCK_FMT_OPTIONS_UNION_SIZE (QBLOCK_PROT_OPTIONS_UNION_SIZE*2)
+union QBlockFmtOptionsUnion {
+    struct QBlockFmtOptionCow       o_cow;
+    struct QBlockFmtOptionQed       o_qed;
+    struct QBlockFmtOptionQcow      o_qcow;
+    struct QBlockFmtOptionQcow2     o_qcow2;
+    struct QBlockFmtOptionRaw       o_raw;
+    struct QBlockFmtOptionRbd       o_rbd;
+    struct QBlockFmtOptionSheepdog  o_sheepdog;
+    struct QBlockFmtOptionVdi       o_vdi;
+    struct QBlockFmtOptionVmdk      o_vmdk;
+    struct QBlockFmtOptionVpc       o_vpc;
+    uint8_t reserved[QBLOCK_FMT_OPTIONS_UNION_SIZE];
+};
+
+struct QBlockFmtInfo {
+    enum QBlockFmtType fmt_type;
+    union QBlockFmtOptionsUnion fmt_op;
+};
+
+/**
+ * QBlockStaticInfo: information about the block image.
+ *
+ * @loc: location info.
+ * @fmt_type: format type.
+ * @virt_size: virtual size in bytes.
+ * @backing_loc: backing file location, its type is QB_PROT_NONE if not exist.
+ * @encrypt: encrypt flag.
+ * @sector_size: how many bytes in a sector, it is 512 usually.
+ */
+struct QBlockStaticInfo {
+    struct QBlockProtInfo loc;
+    enum QBlockFmtType fmt_type;
+    uint64_t virt_size;
+    /* advance info */
+    struct QBlockProtInfo backing_loc;
+    bool encrypt;
+    int sector_size;
+};
+#endif
