• Daniel Vetter's avatar
    mm: extend prefault helpers to fault in more than PAGE_SIZE · f56f821f
    Daniel Vetter authored
    drm/i915 wants to read/write more than one page in its fastpath
    and hence needs to prefault more than PAGE_SIZE bytes.
    Add new functions in filemap.h to make that possible.
    Also kill a copy&pasted spurious space in both functions while at it.
    v2: As suggested by Andrew Morton, add a multipage parameter to both
    functions to avoid the additional branch for the pagemap.c hotpath.
    My gcc 4.6 here seems to dtrt and indeed reap these branches where not
    v3: Becaus I couldn't find a way around adding a uaddr += PAGE_SIZE to
    the filemap.c hotpaths (that the compiler couldn't remove again),
    let's go with separate new functions for the multipage use-case.
    v4: Adjust comment to CodingStlye and fix spelling.
    Acked-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>