• Namjae Jeon's avatar
    fat: fix data past EOF resulting from fsx testsuite · c0ef0cc9
    Namjae Jeon authored
    When running FSX with direct I/O mode, fsx resulted in DATA past EOF issues.
    
      fsx ./file2 -Z -r 4096 -w 4096
      ...
      ..
      truncating to largest ever: 0x907c
      fallocating to largest ever: 0x11137
      truncating to largest ever: 0x2c6fe
      truncating to largest ever: 0x2cfdf
      fallocating to largest ever: 0x40000
      Mapped Read: non-zero data past EOF (0x18628) page offset 0x629 is 0x2a4e
      ...
      ..
    
    The reason being, it is doing a truncate down, but the zeroing does not
    happen on the last block boundary when offset is not aligned.  Even though
    it calls truncate_setsize()->truncate_inode_pages()->
    truncate_inode_pages_range() and considers the partial zeroout but it
    retrieves the page using find_lock_page() - which only looks the page in
    the cache.  So, zeroing out does not happen in case of direct IO.
    
    Make a truncate page based around block_truncate_page for FAT filesystem
    and invoke that helper to zerout in case the offset is not aligned with
    the blocksize.
    Signed-off-by: default avatarNamjae Jeon <namjae.jeon@samsung.com>
    Signed-off-by: default avatarAmit Sahrawat <a.sahrawat@samsung.com>
    Acked-by: default avatarOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    c0ef0cc9
file.c 11.5 KB