Strage values from FIBMAP on holes or after end of file

[utz lehmann <xfs@s2y4n2c.de>]

Hi

The FIBMAP ioctl on holes or after end of file gives the values -1 to 6.
ext2 and reiserfs reurns 0. I thing this is the right value.

The attached programm FIBMAPs the first 32 512byte blocks of a file.

# echo hole >HOLE
# echo hole | dd of=HOLE bs=4096 seek=2
# ./fib HOLE
        0 [0]: 452112
        1 [0]: 452113
        2 [0]: 452114
        3 [0]: 452115
        4 [0]: 452116
        5 [0]: 452117
        6 [0]: 452118
        7 [0]: 452119
        8 [0]: -1
        9 [0]: 0
       10 [0]: 1
       11 [0]: 2
       12 [0]: 3
       13 [0]: 4
       14 [0]: 5
       15 [0]: 6
       16 [0]: 452104
       17 [0]: 452105
       18 [0]: 452106
       19 [0]: 452107
       20 [0]: 452108
       21 [0]: 452109
       22 [0]: 452110
       23 [0]: 452111
       24 [0]: -1
       25 [0]: 0
       26 [0]: 1
       27 [0]: 2
       28 [0]: 3
       29 [0]: 4
       30 [0]: 5
       31 [0]: 6

Blocks 8 - 15 are the hole. Block 23 ist the last block of the file.


utz