• Michal Hocko's avatar
    mm: do not ignore mapping_gfp_mask in page cache allocation paths · 6afdb859
    Michal Hocko authored
    page_cache_read, do_generic_file_read, __generic_file_splice_read and
    __ntfs_grab_cache_pages currently ignore mapping_gfp_mask when calling
    add_to_page_cache_lru which might cause recursion into fs down in the
    direct reclaim path if the mapping really relies on GFP_NOFS semantic.
    This doesn't seem to be the case now because page_cache_read (page fault
    path) doesn't seem to suffer from the reclaim recursion issues and
    do_generic_file_read and __generic_file_splice_read also shouldn't be
    called under fs locks which would deadlock in the reclaim path.  Anyway it
    is better to obey mapping gfp mask and prevent from later breakage.
    [akpm@linux-foundation.org: coding-style fixes]
    Signed-off-by: default avatarMichal Hocko <mhocko@suse.cz>
    Cc: Dave Chinner <david@fromorbit.com>
    Cc: Neil Brown <neilb@suse.de>
    Cc: Johannes Weiner <hannes@cmpxchg.org>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Mel Gorman <mgorman@suse.de>
    Cc: Rik van Riel <riel@redhat.com>
    Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
    Cc: Anton Altaparmakov <anton@tuxera.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
splice.c 46.1 KB