In <asm/paccess.h> I've provided a set of get_user / put_user like functions
that are protecting against DBE exceptions just like get_user / put_user
are protecting against ``normal'' types of page faults. Unlike their
*_user counterparts there is no verify_area equivalent - the kernel is
supposed to know what addresses it is using. These routines are useful
to implement things like hardware detection routines. Or like on the
Origin where I needed them to protect the PCI code against accesses to
the configuration space of non-existant devices. For now the code only
exists for MIPS64 / IP27 but it'll be easy to port.
Ralf
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