• Nick Piggin's avatar
    mm: fault feedback #1 · d0217ac0
    Nick Piggin authored
    Change ->fault prototype.  We now return an int, which contains
    VM_FAULT_xxx code in the low byte, and FAULT_RET_xxx code in the next byte.
     FAULT_RET_ code tells the VM whether a page was found, whether it has been
    locked, and potentially other things.  This is not quite the way he wanted
    it yet, but that's changed in the next patch (which requires changes to
    arch code).
    This means we no longer set VM_CAN_INVALIDATE in the vma in order to say
    that a page is locked which requires filemap_nopage to go away (because we
    can no longer remain backward compatible without that flag), but we were
    going to do that anyway.
    struct fault_data is renamed to struct vm_fault as Linus asked. address
    is now a void __user * that we should firmly encourage drivers not to use
    without really good reason.
    The page is now returned via a page pointer in the vm_fault struct.
    Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>