powerpc/mm: Drop WIMG in favour of new constants
PowerISA 3.0 introduces two pte bits with the below meaning for radix:
00 -> Normal Memory
01 -> Strong Access Order (SAO)
10 -> Non idempotent I/O (Cache inhibited and guarded)
11 -> Tolerant I/O (Cache inhibited)
We drop the existing WIMG bits in the Linux page table in favour of the
above constants. We loose _PAGE_WRITETHRU with this conversion. We only
use writethru via pgprot_cached_wthru() which is used by
fbdev/controlfb.c which is Apple control display and also PPC32.
With respect to _PAGE_COHERENCE, we have been marking hpte always
coherent for some time now. htab_convert_pte_flags() always added
HPTE_R_M.
NOTE: KVM changes need closer review.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h
index 42da513..3c380c2 100644
--- a/arch/powerpc/include/asm/kvm_book3s_64.h
+++ b/arch/powerpc/include/asm/kvm_book3s_64.h
@@ -276,19 +276,24 @@
return ptel;
}
-static inline int hpte_cache_flags_ok(unsigned long ptel, unsigned long io_type)
+static inline bool hpte_cache_flags_ok(unsigned long hptel, bool is_ci)
{
- unsigned int wimg = ptel & HPTE_R_WIMG;
+ unsigned int wimg = hptel & HPTE_R_WIMG;
/* Handle SAO */
if (wimg == (HPTE_R_W | HPTE_R_I | HPTE_R_M) &&
cpu_has_feature(CPU_FTR_ARCH_206))
wimg = HPTE_R_M;
- if (!io_type)
+ if (!is_ci)
return wimg == HPTE_R_M;
-
- return (wimg & (HPTE_R_W | HPTE_R_I)) == io_type;
+ /*
+ * if host is mapped cache inhibited, make sure hptel also have
+ * cache inhibited.
+ */
+ if (wimg & HPTE_R_W) /* FIXME!! is this ok for all guest. ? */
+ return false;
+ return !!(wimg & HPTE_R_I);
}
/*
@@ -325,18 +330,6 @@
return new_pte;
}
-
-/* Return HPTE cache control bits corresponding to Linux pte bits */
-static inline unsigned long hpte_cache_bits(unsigned long pte_val)
-{
-#if _PAGE_NO_CACHE == HPTE_R_I && _PAGE_WRITETHRU == HPTE_R_W
- return pte_val & (HPTE_R_W | HPTE_R_I);
-#else
- return ((pte_val & _PAGE_NO_CACHE) ? HPTE_R_I : 0) +
- ((pte_val & _PAGE_WRITETHRU) ? HPTE_R_W : 0);
-#endif
-}
-
static inline bool hpte_read_permission(unsigned long pp, unsigned long key)
{
if (key)