i.i_block Offset Where It Points
0 to 11 Direct map to file blocks 0 to 11.
12

Indirect block: (file blocks 12 to ($block_size / 4) + 11, or 12 to 1035 if 4KiB blocks)

Indirect Block Offset Where It Points
0 to ($block_size / 4) Direct map to ($block_size / 4) blocks (1024 if 4KiB blocks)
13

Double-indirect block: (file blocks $block_size/4 + 12 to ($block_size / 4) ^ 2 + ($block_size / 4) + 11, or 1036 to 1049611 if 4KiB blocks)

Double Indirect Block Offset Where It Points
0 to ($block_size / 4)

Map to ($block_size / 4) indirect blocks (1024 if 4KiB blocks)

Indirect Block Offset Where It Points
0 to ($block_size / 4) Direct map to ($block_size / 4) blocks (1024 if 4KiB blocks)
14

Triple-indirect block: (file blocks ($block_size / 4) ^ 2 + ($block_size / 4) + 12 to ($block_size / 4) ^ 3 + ($block_size / 4) ^ 2 + ($block_size / 4) + 12, or 1049612 to 1074791436 if 4KiB blocks)

Triple Indirect Block Offset Where It Points
0 to ($block_size / 4)

Map to ($block_size / 4) double indirect blocks (1024 if 4KiB blocks)

Double Indirect Block Offset Where It Points
0 to ($block_size / 4)

Map to ($block_size / 4) indirect blocks (1024 if 4KiB blocks)

Indirect Block Offset Where It Points
0 to ($block_size / 4) Direct map to ($block_size / 4) blocks (1024 if 4KiB blocks)