Alexander Graf <agraf@xxxxxxx> writes:
> On 07/02/2013 05:29 PM, Aneesh Kumar K.V wrote:
>> Alexander Graf<agraf@xxxxxxx> writes:
>>
>>> On 07/02/2013 07:45 AM, Aneesh Kumar K.V wrote:
>>>> From: "Aneesh Kumar K.V"<aneesh.kumar@xxxxxxxxxxxxxxxxxx>
>>>>
>>>> Older version of power architecture use Real Mode Offset register and Real Mode Limit
>>>> Selector for mapping guest Real Mode Area. The guest RMA should be physically
>>>> contigous since we use the range when address translation is not enabled.
>>>>
>>>> This patch switch RMA allocation code to use contigous memory allocator. The patch
>>>> also remove the the linear allocator which not used any more
>>>>
>>>> Acked-by: Paul Mackerras<paulus@xxxxxxxxx>
>>>> Signed-off-by: Aneesh Kumar K.V<aneesh.kumar@xxxxxxxxxxxxxxxxxx>
>>>> ---
>> .... snip ....
>>
>>>> diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
>>>> index 550f592..55c8519 100644
>>>> --- a/arch/powerpc/kvm/book3s_hv.c
>>>> +++ b/arch/powerpc/kvm/book3s_hv.c
>>>> @@ -1511,10 +1511,10 @@ static inline int lpcr_rmls(unsigned long rma_size)
>>>>
>>>> static int kvm_rma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
>>>> {
>>>> - struct kvmppc_linear_info *ri = vma->vm_file->private_data;
>>>> struct page *page;
>>>> + struct kvm_rma_info *ri = vma->vm_file->private_data;
>>>>
>>>> - if (vmf->pgoff>= ri->npages)
>>>> + if (vmf->pgoff>= kvm_rma_pages)
>>>> return VM_FAULT_SIGBUS;
>>>>
>>>> page = pfn_to_page(ri->base_pfn + vmf->pgoff);
>>>> @@ -1536,7 +1536,7 @@ static int kvm_rma_mmap(struct file *file, struct vm_area_struct *vma)
>>>>
>>>> static int kvm_rma_release(struct inode *inode, struct file *filp)
>>>> {
>>>> - struct kvmppc_linear_info *ri = filp->private_data;
>>>> + struct kvm_rma_info *ri = filp->private_data;
>>>>
>>>> kvm_release_rma(ri);
>>>> return 0;
>>>> @@ -1549,8 +1549,17 @@ static const struct file_operations kvm_rma_fops = {
>>>>
>>>> long kvm_vm_ioctl_allocate_rma(struct kvm *kvm, struct kvm_allocate_rma *ret)
>>>> {
>>>> - struct kvmppc_linear_info *ri;
>>>> long fd;
>>>> + struct kvm_rma_info *ri;
>>>> + /*
>>>> + * Only do this on PPC970 in HV mode
>>>> + */
>>>> + if (!cpu_has_feature(CPU_FTR_HVMODE) ||
>>>> + !cpu_has_feature(CPU_FTR_ARCH_201))
>>>> + return -EINVAL;
>>> Is this really what we want? User space may want to use an RMA on POWER7
>>> systems, no?
>> IIUC they will use virtual real mode area (VRMA) and not RMA
>
> Then I suppose we should at least update the comment a bit further down
> the patch that indicates that on POWER7 systems we do support a real
> RMA. I can't really think of any reason why user space would want to use
> RMA over VRMA.
>
where ? We have comments like
/* On POWER7, use VRMA; on PPC970, give up */
-aneesh
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>