powerpc/mm: Use appropriate ESID mask in copro_calculate_slb()

This patch makes copro_calculate_slb() mask the ESID by the correct mask
for 1T vs 256M segments.

This has no effect by itself as the extra bits were ignored, but it
makes debugging the segment table entries easier and means that we can
directly compare the ESID values for duplicates without needing to worry
about masking in the comparison.

This will be used to simplify a comparison in the following patch.
Signed-off-by: NIan Munsie <imunsie@au1.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

arch/powerpc/mm/copro_fault.c

@@ -99,8 +99,6 @@ int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb)
 	u64 vsid;
 	int psize, ssize;
 
-	slb->esid = (ea & ESID_MASK) | SLB_ESID_V;
-
 	switch (REGION_ID(ea)) {
 	case USER_REGION_ID:
 		pr_devel("%s: 0x%llx -- USER_REGION_ID\n", __func__, ea);
@@ -133,6 +131,7 @@ int copro_calculate_slb(struct mm_struct *mm, u64 ea, struct copro_slb *slb)
 	vsid |= mmu_psize_defs[psize].sllp |
 		((ssize == MMU_SEGSIZE_1T) ? SLB_VSID_B_1T : 0);
 
+	slb->esid = (ea & (ssize == MMU_SEGSIZE_1T ? ESID_MASK_1T : ESID_MASK)) | SLB_ESID_V;
 	slb->vsid = vsid;
 
 	return 0;