Subject: Re: [RFC PATCH -V2 08/21] powerpc: Decode the pte-lp-encoding bits correctly.

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Sun, 24 Feb 2013 23:15:28 +0530

Paul Mackerras <[email-masked]> writes:

>
>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>> index 71d0c90..d2c9932 100644
>> --- a/arch/powerpc/kvm/book3s_hv.c
>> +++ b/arch/powerpc/kvm/book3s_hv.c
>> @@ -1515,7 +1515,12 @@ static void kvmppc_add_seg_page_size(struct kvm_ppc_one_seg_page_size **sps,
>>  	(*sps)->page_shift = def->shift;
>>  	(*sps)->slb_enc = def->sllp;
>>  	(*sps)->enc[0].page_shift = def->shift;
>> -	(*sps)->enc[0].pte_enc = def->penc;
>> +	/*
>> +	 * FIXME!!
>> +	 * This is returned to user space. Do we need to
>> +	 * return details of MPSS here ?
>
> Yes, we do, probably a separate entry for each valid base/actual page
> size pair.
>

How about

commit fb7bca460d5e3a517dce24c0fe28cc94ffde37fa
Author: Aneesh Kumar K.V <[email-masked]>
Date:   Sun Feb 24 22:55:38 2013 +0530

    powerpc: Return all the valid pte ecndoing in KVM_PPC_GET_SMMU_INFO ioctl
    
    Signed-off-by: Aneesh Kumar K.V <[email-masked]>

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 48f6d99..e50eb0d 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1508,14 +1508,21 @@ long kvm_vm_ioctl_allocate_rma(struct kvm *kvm, struct kvm_allocate_rma *ret)
 static void kvmppc_add_seg_page_size(struct kvm_ppc_one_seg_page_size **sps,
 				     int linux_psize)
 {
+	int i, index = 0;
 	struct mmu_psize_def *def = &mmu_psize_defs[linux_psize];
 
 	if (!def->shift)
 		return;
 	(*sps)->page_shift = def->shift;
 	(*sps)->slb_enc = def->sllp;
-	(*sps)->enc[0].page_shift = def->shift;
-	(*sps)->enc[0].pte_enc = def->penc[linux_psize];
+	for (i = 0; i < MMU_PAGE_COUNT; i++) {
+		if ((signed int)def->penc[i] != -1) {
+			BUG_ON(index >= KVM_PPC_PAGE_SIZES_MAX_SZ);
+			(*sps)->enc[index].page_shift = mmu_psize_defs[i].shift;
+			(*sps)->enc[index].pte_enc = def->penc[i];
+			index++;
+		}
+	}
 	(*sps)++;
 }