• Hugh Dickins's avatar
    tmpfs: support SEEK_DATA and SEEK_HOLE (reprise) · 220f2ac9
    Hugh Dickins authored
    Revert 3.5's commit f21f8062 ("tmpfs: revert SEEK_DATA and
    SEEK_HOLE") to reinstate 4fb5ef08 ("tmpfs: support SEEK_DATA and
    SEEK_HOLE"), with the intervening additional arg to
    generic_file_llseek_size().
    
    In 3.8, ext4 is expected to join btrfs, ocfs2 and xfs with proper
    SEEK_DATA and SEEK_HOLE support; and a good case has now been made for
    it on tmpfs, so let's join the party.
    
    It's quite easy for tmpfs to scan the radix_tree to support llseek's new
    SEEK_DATA and SEEK_HOLE options: so add them while the minutiae are
    still on my mind (in particular, the !PageUptodate-ness of pages
    fallocated but still unwritten).
    
    [akpm@linux-foundation.org: fix warning with CONFIG_TMPFS=n]
    Signed-off-by: default avatarHugh Dickins <hughd@google.com>
    Cc: Dave Chinner <david@fromorbit.com>
    Cc: Jaegeuk Hanse <jaegeuk.hanse@gmail.com>
    Cc: "Theodore Ts'o" <tytso@mit.edu>
    Cc: Zheng Liu <wenqing.lz@taobao.com>
    Cc: Jeff liu <jeff.liu@oracle.com>
    Cc: Paul Eggert <eggert@cs.ucla.edu>
    Cc: Christoph Hellwig <hch@infradead.org>
    Cc: Josef Bacik <josef@redhat.com>
    Cc: Andi Kleen <andi@firstfloor.org>
    Cc: Andreas Dilger <adilger@dilger.ca>
    Cc: Marco Stornelli <marco.stornelli@gmail.com>
    Cc: Chris Mason <chris.mason@fusionio.com>
    Cc: Sunil Mushran <sunil.mushran@oracle.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    220f2ac9
shmem.c 76.8 KB