• Benjamin Herrenschmidt's avatar
    powerpc ioremap_prot · a1f242ff
    Benjamin Herrenschmidt authored
    This adds ioremap_prot and pte_pgprot() so that one can extract protection
    bits from a PTE and use them to ioremap_prot() (in order to support ptrace
    of VM_IO | VM_PFNMAP as per Rik's patch).
    
    This moves a couple of flag checks around in the ioremap implementations
    of arch/powerpc.  There's a side effect of allowing non-cacheable and
    non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED
    set whenever _PAGE_NO_CACHE is.
    
    (standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be
    capable of setting such a non guarded mapping).
    Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
    Signed-off-by: default avatarRik van Riel <riel@redhat.com>
    Cc: Dave Airlie <airlied@linux.ie>
    Cc: Hugh Dickins <hugh@veritas.com>
    Cc: Paul Mackerras <paulus@samba.org>
    Cc: Arnd Bergmann <arnd@arndb.de>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    a1f242ff
pgtable_32.c 9.71 KB