EbFS

Encryption based File system

Inode structure:

Technical Specification(Data Structures):

General Overview of Inode Structure

Overview of Project

Block size of disk : 4096-byte (4 KiB) (which are used by Newer HDDs)

Data Structures:

1. Superblock:

   Attributes of superblock:
   Size of disk
   Information of Inode blocks ( total number of inodeblocks , etc..)
   Information of bitmap blocks ( starting of bit map blocks , etc.. )
   Total Size of Superblock: 28 bytes
   Location in source code:superblock.c

2. Inode:

   Attributes of inodes:
   Metadata (contains information of filetype, etc.. )
   Blockdata (direct blocks ,indirect blocks , etc..)
   And other information containing flag like is Allocated.

   Total Size of Inode : 72 bytes
   Maximum Number of inodes in per block : 50 inodes per block
   Location in source code: inode.c and inode.h

3. File_entry:

   Attributes of File_entry:
   File name
   Inode number

   Total size of File_entry : 32 bytes [ 28 bytes of file-name + 4 bytes of inode number ].
   Maximum number of File_entry in each block : 128
   Location in source code:filesystem.c

1. Union block_rw:

   Attributes of block_rw:
   Char array of size 4096 bytes
   Super block
   Array of inode block
   Array of file entries
   Size of block_rw : Block size of disk ( 4096 bytes)
   Location in source code:filesystem.c
   Disk can not be read and write single bit and byte.We have to read and write in terms of block size of disk.That’s why we
   used Union block_rw for reading and writing data into disk.

Assumption :

• We are using Disk emulator which has no IO scheduling algorithms.