On 12.02.20 14:42, Cornelia Huck wrote:
> On Fri, 7 Feb 2020 06:39:28 -0500
> Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote:
>
>> From: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
>>
>> This provides the basic ultravisor calls and page table handling to cope
>> with secure guests:
>> - provide arch_make_page_accessible
>> - make pages accessible after unmapping of secure guests
>> - provide the ultravisor commands convert to/from secure
>> - provide the ultravisor commands pin/unpin shared
>> - provide callbacks to make pages secure (inacccessible)
>> - we check for the expected pin count to only make pages secure if the
>> host is not accessing them
>> - we fence hugetlbfs for secure pages
>>
>> Co-developed-by: Ulrich Weigand <Ulrich.Weigand@xxxxxxxxxx>
>> Signed-off-by: Ulrich Weigand <Ulrich.Weigand@xxxxxxxxxx>
>> Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
>> [borntraeger@xxxxxxxxxx: patch merging, splitting, fixing]
>> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
>> ---
>> arch/s390/include/asm/gmap.h | 2 +
>> arch/s390/include/asm/mmu.h | 2 +
>> arch/s390/include/asm/mmu_context.h | 1 +
>> arch/s390/include/asm/page.h | 5 +
>> arch/s390/include/asm/pgtable.h | 34 +++++-
>> arch/s390/include/asm/uv.h | 52 +++++++++
>> arch/s390/kernel/uv.c | 172 ++++++++++++++++++++++++++++
>> 7 files changed, 263 insertions(+), 5 deletions(-)
>
> (...)
>
>> +/*
>> + * Requests the Ultravisor to encrypt a guest page and make it
>> + * accessible to the host for paging (export).
>> + *
>> + * @paddr: Absolute host address of page to be exported
>> + */
>> +int uv_convert_from_secure(unsigned long paddr)
>> +{
>> + struct uv_cb_cfs uvcb = {
>> + .header.cmd = UVC_CMD_CONV_FROM_SEC_STOR,
>> + .header.len = sizeof(uvcb),
>> + .paddr = paddr
>> + };
>> +
>> + uv_call(0, (u64)&uvcb);
>> +
>> + if (uvcb.header.rc == 1 || uvcb.header.rc == 0x107)
>
> I think this either wants a comment or some speaking #defines.
Yes. We will improve some other aspects of this patch, but I will add
/* Return on success or if this page was already exported */
>
>> + return 0;
>> + return -EINVAL;
>> +}
>
> (...)
>
