diff --git a/src/fs/file.c b/src/fs/file.c
index d0f304f..4137d6b 100644
--- a/src/fs/file.c
+++ b/src/fs/file.c
@@ -245,29 +245,40 @@ void initialize_flash(bool hard) {
     dynamic_files = 0;
 }
 
-void scan_region(bool persistent) {
+extern uintptr_t last_base;
+extern uint32_t num_files;
+void scan_region(bool persistent)
+{
     uintptr_t endp = end_data_pool, startp = start_data_pool;
     if (persistent) {
         endp = end_rom_pool;
         startp = start_rom_pool;
     }
+    else {
+        last_base = endp;
+        num_files = 0;
+    }
     for (uintptr_t base = flash_read_uintptr(endp); base >= startp; base = flash_read_uintptr(base)) {
         if (base == 0x0) { //all is empty
             break;
         }
 
         uint16_t fid = flash_read_uint16(base + sizeof(uintptr_t) + sizeof(uintptr_t));
-        printf("[%x] scan fid %x, len %d\n", (unsigned int) base, fid,
-               flash_read_uint16(base + sizeof(uintptr_t) + sizeof(uintptr_t) + sizeof(uint16_t)));
+        printf("[%x] scan fid %x, len %d\n", (unsigned int) base, fid, flash_read_uint16(base + sizeof(uintptr_t) + sizeof(uintptr_t) + sizeof(uint16_t)));
         file_t *file = (file_t *) search_by_fid(fid, NULL, SPECIFY_EF);
         if (!file) {
             file = file_new(fid);
         }
         if (file) {
-            file->data =
-                (uint8_t *) (base + sizeof(uintptr_t) + sizeof(uintptr_t) + sizeof(uint16_t));
+            file->data = (uint8_t *) (base + sizeof(uintptr_t) + sizeof(uintptr_t) + sizeof(uint16_t));
+        }
+        if (!persistent) {
+            num_files++;
         }
         if (flash_read_uintptr(base) == 0x0) {
+            if (base < last_base) {
+                last_base = base;
+            }
             break;
         }
     }
diff --git a/src/fs/file.h b/src/fs/file.h
index b69ccbc..072786f 100644
--- a/src/fs/file.h
+++ b/src/fs/file.h
@@ -128,6 +128,12 @@ extern int meta_delete(uint16_t fid);
 extern int meta_add(uint16_t fid, const uint8_t *data, uint16_t len);
 extern int delete_file(file_t *ef);
 
+extern uint32_t flash_free_space();
+extern uint32_t flash_used_space();
+extern uint32_t flash_total_space();
+extern uint32_t flash_num_files();
+extern uint32_t flash_size();
+
 #ifndef ENABLE_EMULATION
 extern file_t *ef_phy;
 #endif
diff --git a/src/fs/flash.c b/src/fs/flash.c
index 96dd091..d1d63cd 100644
--- a/src/fs/flash.c
+++ b/src/fs/flash.c
@@ -73,12 +73,14 @@ extern uint8_t *flash_read(uintptr_t addr);
 
 extern void low_flash_available();
 
+uintptr_t last_base = end_data_pool;
+uint32_t num_files = 0;
+
 uintptr_t allocate_free_addr(uint16_t size, bool persistent) {
     if (size > FLASH_SECTOR_SIZE) {
         return 0x0; //ERROR
     }
-    size_t real_size = size + sizeof(uint16_t) + sizeof(uintptr_t) + sizeof(uint16_t) +
-                       sizeof(uintptr_t);                                                          //len+len size+next address+fid+prev_addr size
+    size_t real_size = size + sizeof(uint16_t) + sizeof(uintptr_t) + sizeof(uint16_t) + sizeof(uintptr_t); //len+len size+next address+fid+prev_addr size
     uintptr_t next_base = 0x0, endp = end_data_pool, startp = start_data_pool;
     if (persistent) {
         endp = end_rom_pool;
@@ -108,14 +110,9 @@ uintptr_t allocate_free_addr(uint16_t size, bool persistent) {
             return 0x0;
         }
         //we check if |base-(next_addr+size_next_addr)| > |base-potential_addr| only if fid != 1xxx (not size blocked)
-        else if (addr_alg <= potential_addr &&
-                 base -
-                 (next_base +
-                  flash_read_uint16(next_base + sizeof(uintptr_t) + sizeof(uintptr_t) +
-                                    sizeof(uint16_t)) +
-                  2 *
-                  sizeof(uint16_t) + 2 * sizeof(uintptr_t)) > base - potential_addr &&
-                 (flash_read_uint16(next_base + 2 * sizeof(uintptr_t)) & 0x1000) != 0x1000) {
+        else if (addr_alg <= potential_addr
+            && base - (next_base + flash_read_uint16(next_base + sizeof(uintptr_t) + sizeof(uintptr_t) + sizeof(uint16_t)) + 2 * sizeof(uint16_t) + 2 * sizeof(uintptr_t)) > base - potential_addr
+            && (flash_read_uint16(next_base + 2 * sizeof(uintptr_t)) & 0x1000) != 0x1000) {
             flash_program_uintptr(potential_addr, next_base);
             flash_program_uintptr(next_base + sizeof(uintptr_t), potential_addr);
             flash_program_uintptr(potential_addr + sizeof(uintptr_t), base);
@@ -130,8 +127,7 @@ int flash_clear_file(file_t *file) {
     if (file == NULL || file->data == NULL) {
         return PICOKEY_OK;
     }
-    uintptr_t base_addr =
-        (uintptr_t)(file->data - sizeof(uintptr_t) - sizeof(uint16_t) - sizeof(uintptr_t));
+    uintptr_t base_addr = (uintptr_t)(file->data - sizeof(uintptr_t) - sizeof(uint16_t) - sizeof(uintptr_t));
     uintptr_t prev_addr = flash_read_uintptr(base_addr + sizeof(uintptr_t));
     uintptr_t next_addr = flash_read_uintptr(base_addr);
     //printf("nc %lx->%lx   %lx->%lx\n",prev_addr,flash_read_uintptr(prev_addr),base_addr,next_addr);
@@ -143,12 +139,12 @@ int flash_clear_file(file_t *file) {
     flash_program_uintptr(base_addr, 0);
     flash_program_uintptr(base_addr + sizeof(uintptr_t), 0);
     file->data = NULL;
+    num_files--;
     //printf("na %lx->%lx\n",prev_addr,flash_read_uintptr(prev_addr));
     return PICOKEY_OK;
 }
 
-int flash_write_data_to_file_offset(file_t *file, const uint8_t *data, uint16_t len,
-                                    uint16_t offset) {
+int flash_write_data_to_file_offset(file_t *file, const uint8_t *data, uint16_t len, uint16_t offset) {
     if (!file) {
         return PICOKEY_ERR_NULL_PARAM;
     }
@@ -182,6 +178,9 @@ int flash_write_data_to_file_offset(file_t *file, const uint8_t *data, uint16_t
     if (new_addr == 0x0) {
         return PICOKEY_ERR_NO_MEMORY;
     }
+    if (new_addr < last_base) {
+        last_base = new_addr;
+    }
     file->data = (uint8_t *) new_addr + sizeof(uintptr_t) + sizeof(uint16_t) + sizeof(uintptr_t); //next addr+fid+prev addr
     flash_program_halfword(new_addr + sizeof(uintptr_t) + sizeof(uintptr_t), file->fid);
     flash_program_halfword((uintptr_t) file->data, len);
@@ -191,8 +190,30 @@ int flash_write_data_to_file_offset(file_t *file, const uint8_t *data, uint16_t
     if (old_data) {
         free(old_data);
     }
+    num_files++;
     return PICOKEY_OK;
 }
+
 int flash_write_data_to_file(file_t *file, const uint8_t *data, uint16_t len) {
     return flash_write_data_to_file_offset(file, data, len, 0);
 }
+
+uint32_t flash_free_space() {
+    return last_base - start_data_pool;
+}
+
+uint32_t flash_used_space() {
+    return end_data_pool - last_base;
+}
+
+uint32_t flash_total_space() {
+    return end_data_pool - start_data_pool;
+}
+
+uint32_t flash_num_files() {
+    return num_files;
+}
+
+uint32_t flash_size() {
+    return PICO_FLASH_SIZE_BYTES;
+}