How Check Disk Space Available In A Partition In C

• crash –> mount and grab the superblock hex address.
• Then run struct super_block <HEX_ADDRESS>
• The values of importance are s_blocksize, s_blocks_count, and s_free_blocks_count
• To calculate disk sizes: Total Sise: s_blocksize * s_blocks_count Free Sise: s_blocksize * s_free_blocks_count Used Sise: Total Sise - Free Sise
• For XFS, not all values ares shown:

  crash> struct super_block ff41a507c000b800 | grep -e s_blocksize -e s_blocks_count -e s_free_blocks_count
  s_blocksize_bits = 12 '\f',
  s_blocksize = 4096,
  

• Need to look at the memory address of the struct, not the virtual address produced by sym -l.
• We usually should see xfs_sb or xfs_mount as bare options from sym -l