• Hugh Dickins's avatar
    [PATCH] unpaged: COW on VM_UNPAGED · 920fc356
    Hugh Dickins authored
    Remove the BUG_ON(vma->vm_flags & VM_UNPAGED) from do_wp_page, and let it do
    Copy-On-Write without touching the VM_UNPAGED's page counts - but this is
    incomplete, because the anonymous page it inserts will itself need to be
    handled, here and in other functions - next patch.
    
    We still don't copy the page if the pfn is invalid, because the
    copy_user_highpage interface does not allow it.  But that's not been a problem
    in the past: can be added in later if the need arises.
    Signed-off-by: default avatarHugh Dickins <hugh@veritas.com>
    Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
    920fc356
memory.c 59.5 KB