powerpc/mm/book3s-64: Move _PAGE_PRESENT to the most significant bit

This changes _PAGE_PRESENT for 64-bit Book 3S processors from 0x2 to
0x8000_0000_0000_0000, because that is where PowerISA v3.0 CPUs in
radix mode will expect to find it.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 5 insertions, 5 deletions

diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index a8c4c2a1940b..ed390e1915b7 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -210,30 +210,30 @@ static inline char *get_hpte_slot_array(pmd_t *pmdp)
 /*
  * The linux hugepage PMD now include the pmd entries followed by the address
  * to the stashed pgtable_t. The stashed pgtable_t contains the hpte bits.
- * [ 1 bit secondary | 3 bit hidx | 1 bit valid | 000]. We use one byte per
+ * [ 000 | 1 bit secondary | 3 bit hidx | 1 bit valid]. We use one byte per
  * each HPTE entry. With 16MB hugepage and 64K HPTE we need 256 entries and
  * with 4K HPTE we need 4096 entries. Both will fit in a 4K pgtable_t.
  *
- * The last three bits are intentionally left to zero. This memory location
+ * The top three bits are intentionally left as zero. This memory location
  * are also used as normal page PTE pointers. So if we have any pointers
  * left around while we collapse a hugepage, we need to make sure
  * _PAGE_PRESENT bit of that is zero when we look at them
  */
 static inline unsigned int hpte_valid(unsigned char *hpte_slot_array, int index)
 {
-	return (hpte_slot_array[index] >> 3) & 0x1;
+	return hpte_slot_array[index] & 0x1;
 }
 
 static inline unsigned int hpte_hash_index(unsigned char *hpte_slot_array,
 					   int index)
 {
-	return hpte_slot_array[index] >> 4;
+	return hpte_slot_array[index] >> 1;
 }
 
 static inline void mark_hpte_slot_valid(unsigned char *hpte_slot_array,
 					unsigned int index, unsigned int hidx)
 {
-	hpte_slot_array[index] = hidx << 4 | 0x1 << 3;
+	hpte_slot_array[index] = (hidx << 1) | 0x1;
 }
 
 /*