diff --git a/src/minivhd.h b/src/minivhd.h
index 5e3a3a1..9bbd428 100644
--- a/src/minivhd.h
+++ b/src/minivhd.h
@@ -11,7 +11,7 @@ typedef enum MVHDType {
 } MVHDType;
 
 typedef enum MVHDError {
-    MVHD_ERR_MEM = -1,
+    MVHD_ERR_MEM,
     MVHD_ERR_FILE,
     MVHD_ERR_NOT_VHD,
     MVHD_ERR_TYPE,
@@ -22,9 +22,10 @@ typedef enum MVHDError {
 typedef struct MVHDMeta {
     FILE* f;
     char* filename;
+    struct MVHDMeta* parent;
     MVHDFooter footer;
     MVHDSparseHeader sparse;
-    struct MVHDMeta* parent;
+    MVHDBlock* block;
 } MVHDMeta;
 
 MVHDMeta* mvhd_open(const char* path, int* err);
diff --git a/src/minivhd_internal.h b/src/minivhd_internal.h
index d815aba..6e5ead0 100644
--- a/src/minivhd_internal.h
+++ b/src/minivhd_internal.h
@@ -6,53 +6,59 @@
 #define MVHD_FOOTER_SIZE 512
 #define MVHD_SPARSE_SIZE 1024
 
-typedef struct MVHDFooter
-{
-        uint8_t cookie[8];
-        uint32_t features;
-        uint32_t fi_fmt_vers;
-        uint64_t data_offset;
-        uint32_t timestamp;
-        uint8_t cr_app[4];
-        uint32_t cr_vers;
-        uint8_t cr_host_os[4];
-        uint64_t orig_sz;
-        uint64_t curr_sz;
-        struct {
-                uint16_t cyl;
-                uint8_t heads;
-                uint8_t spt;
-        } geom;
-        uint32_t disk_type;
-        uint32_t checksum;
-        uint8_t uuid[16];
-        uint8_t saved_st;
-        uint8_t reserved[427];
+#define MVHD_SECTOR_SIZE 512
+#define MVHD_MAX_BLOCK_SIZE 0x00200000
+
+typedef struct MVHDFooter {
+    uint8_t cookie[8];
+    uint32_t features;
+    uint32_t fi_fmt_vers;
+    uint64_t data_offset;
+    uint32_t timestamp;
+    uint8_t cr_app[4];
+    uint32_t cr_vers;
+    uint8_t cr_host_os[4];
+    uint64_t orig_sz;
+    uint64_t curr_sz;
+    struct {
+        uint16_t cyl;
+        uint8_t heads;
+        uint8_t spt;
+    } geom;
+    uint32_t disk_type;
+    uint32_t checksum;
+    uint8_t uuid[16];
+    uint8_t saved_st;
+    uint8_t reserved[427];
 } MVHDFooter;
 
-typedef struct MVHDSparseHeader
-{
-        uint8_t cookie[8];
-        uint64_t data_offset;
-        uint64_t bat_offset;
-        uint32_t head_vers;
-        uint32_t max_bat_ent;
-        uint32_t block_sz;
-        uint32_t checksum;
-        uint8_t par_uuid[16];
-        uint32_t par_timestamp;
-        uint32_t reserved_1;
-        uint8_t par_utf16_name[512];
-        struct {
-                uint32_t plat_code;
-                uint32_t plat_data_space;
-                uint32_t plat_data_len;
-                uint32_t reserved;
-                uint64_t plat_data_offset;
-        } par_loc_entry[8];
-        uint8_t reserved_2[256];
+typedef struct MVHDSparseHeader {
+    uint8_t cookie[8];
+    uint64_t data_offset;
+    uint64_t bat_offset;
+    uint32_t head_vers;
+    uint32_t max_bat_ent;
+    uint32_t block_sz;
+    uint32_t checksum;
+    uint8_t par_uuid[16];
+    uint32_t par_timestamp;
+    uint32_t reserved_1;
+    uint8_t par_utf16_name[512];
+    struct {
+        uint32_t plat_code;
+        uint32_t plat_data_space;
+        uint32_t plat_data_len;
+        uint32_t reserved;
+        uint64_t plat_data_offset;
+    } par_loc_entry[8];
+    uint8_t reserved_2[256];
 } MVHDSparseHeader;
 
+typedef struct MVHDBlock {
+    uint8_t* bitmap;
+    uint32_t offset;
+} MVHDBlock;
+
 bool mvhd_is_conectix_str(const void* buffer);
 void mvhd_buffer_to_footer(MVHDFooter* footer, uint8_t* buffer);
 void mvhd_buffer_to_header(MVHDSparseHeader* header, uint8_t* buffer);
diff --git a/src/minivhd_manage.c b/src/minivhd_manage.c
index b85cb79..4423fbe 100644
--- a/src/minivhd_manage.c
+++ b/src/minivhd_manage.c
@@ -114,5 +114,18 @@ end:
 }
 
 void mvhd_close(MVHDMeta* vhdm) {
+    if (vhdm->parent != NULL) {
+        mvhd_close(vhdm->parent);
+    }
     fclose(vhdm->f);
+    if (vhdm->block != NULL) {
+        for (uint32_t i = 0; i < vhdm->sparse.max_bat_ent; i++) {
+            free(vhdm->block[i].bitmap);
+            vhdm->block[i].bitmap = NULL;
+        }
+        free(vhdm->block);
+        vhdm->block = NULL;
+    }
+    free(vhdm);
+    vhdm = NULL;
 }
\ No newline at end of file