• Steven Whitehouse's avatar
    GFS2: Use range based functions for rgrp sync/invalidation · 7005c3e4
    Steven Whitehouse authored
    
    
    Each rgrp header is represented as a single extent on disk, so we
    can calculate the position within the address space, since we are
    using address spaces mapped 1:1 to the disk. This means that it
    is possible to use the range based versions of filemap_fdatawrite/wait
    and for invalidating the page cache.
    
    Our eventual intent is to then be able to merge the address spaces
    used for rgrps into a single address space, rather than to have
    one for each glock, saving memory and reducing complexity.
    
    Since during umount, the rgrp structures are disposed of before
    the glocks, we need to store the extent information in the glock
    so that is is available for a final invalidation. This patch uses
    a field which is otherwise unused in rgrp glocks to do that, so
    that we do not have to expand the size of a glock.
    Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
    7005c3e4