OSDN Git Service
filefrag: Display the number of contiguous, not physical, extents
From a bug report filed by Ibragimov Rinat:
When filefrag uses FIEMAP ioctl its logic differs for ordinary and
verbose (-v) modes. ext4 returns extent on every 32768 block so on
large files it is possible that `filefrag large-file' tells about 4
extents while `filefrag -v large-file' finds only one.
Also when I tried to use generic_block_fiemap function to add
FIEMAP for reiserfs, every block was reported as a new extent
resulting in thousands "extents" for continuous files.
I think filefrag should merge adjacent extents even when -v is not
specified.
Addresses-Debian-Bug: #631498
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>