Re: [PATCH v2 18/19] iommu/vt-d: Support flushing more translation cache types

Auger Eric
2019-04-30T04:41:13Z

Hi Jacob,

On 4/29/19 11:29 PM, Jacob Pan wrote:
> On Sat, 27 Apr 2019 11:04:04 +0200
> Auger Eric <eric.auger-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
>
>> Hi Jacob,
>>
>> On 4/24/19 1:31 AM, Jacob Pan wrote:
>>> When Shared Virtual Memory is exposed to a guest via vIOMMU,
>>> extended IOTLB invalidation may be passed down from outside IOMMU
>>> subsystems. This patch adds invalidation functions that can be used
>>> for additional translation cache types.
>>>
>>> Signed-off-by: Jacob Pan <jacob.jun.pan-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
>>> ---
>>> drivers/iommu/dmar.c | 48
>>> +++++++++++++++++++++++++++++++++++++++++++++
>>> include/linux/intel-iommu.h | 21 ++++++++++++++++---- 2 files
>>> changed, 65 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
>>> index 9c49300..680894e 100644
>>> --- a/drivers/iommu/dmar.c
>>> +++ b/drivers/iommu/dmar.c
>>> @@ -1357,6 +1357,20 @@ void qi_flush_iotlb(struct intel_iommu
>>> *iommu, u16 did, u64 addr, qi_submit_sync(&desc, iommu);
>>> }
>>>
>> /* PASID-based IOTLB Invalidate */
>>> +void qi_flush_piotlb(struct intel_iommu *iommu, u16 did, u64 addr,
>>> u32 pasid,
>>> + unsigned int size_order, u64 granu)
>>> +{
>>> + struct qi_desc desc;
>>> +
>>> + desc.qw0 = QI_EIOTLB_PASID(pasid) | QI_EIOTLB_DID(did) |
>>> + QI_EIOTLB_GRAN(granu) | QI_EIOTLB_TYPE;
>>> + desc.qw1 = QI_EIOTLB_ADDR(addr) | QI_EIOTLB_IH(0) |
>>> + QI_EIOTLB_AM(size_order);
>> I see IH it hardcoded to 0. Don't you envision to cascade the IH. On
>> ARM this was needed for perf sake.
> Right, we should cascade IH based on IOMMU_INV_ADDR_FLAGS_LEAF. Just
> curious how do you deduce the IH information on ARM? I guess you need
> to get the non-leaf page directory info?
> I will add an argument for IH.
On ARM we have the "Leaf" field in the stage1 TLB invalidation command.
"When Leaf==1, only cached entries for the last level of translation
table walk are required to be invalidated".

Thanks

Eric
>>> + desc.qw2 = 0;
>>> + desc.qw3 = 0;
>>> + qi_submit_sync(&desc, iommu);
>>> +}
>>> +
>>> void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16
>>> pfsid, u16 qdep, u64 addr, unsigned mask)
>>> {
>>> @@ -1380,6 +1394,40 @@ void qi_flush_dev_iotlb(struct intel_iommu
>>> *iommu, u16 sid, u16 pfsid, qi_submit_sync(&desc, iommu);
>>> }
>>>
>> /* Pasid-based Device-TLB Invalidation */
> yes, better to explain piotlb :), same for iotlb.
>>> +void qi_flush_dev_piotlb(struct intel_iommu *iommu, u16 sid, u16
>>> pfsid,
>>> + u32 pasid, u16 qdep, u64 addr, unsigned size, u64
>>> granu) +{
>>> + struct qi_desc desc;
>>> +
>>> + desc.qw0 = QI_DEV_EIOTLB_PASID(pasid) |
>>> QI_DEV_EIOTLB_SID(sid) |
>>> + QI_DEV_EIOTLB_QDEP(qdep) | QI_DEIOTLB_TYPE |
>>> + QI_DEV_IOTLB_PFSID(pfsid);
>>> + desc.qw1 |= QI_DEV_EIOTLB_GLOB(granu);
> should be desc.qw1 =
>>> +
>>> + /* If S bit is 0, we only flush a single page. If S bit is
>>> set,
>>> + * The least significant zero bit indicates the size. VT-d
>>> spec
>>> + * 6.5.2.6
>>> + */
>>> + if (!size)
>>> + desc.qw0 = QI_DEV_EIOTLB_ADDR(addr) &
>>> ~QI_DEV_EIOTLB_SIZE;
>> desc.q1 |= ?
> Right, I also missed previous qw1 assignment.
>>> + else {
>>> + unsigned long mask = 1UL << (VTD_PAGE_SHIFT +
>>> size); +
>>> + desc.qw1 = QI_DEV_EIOTLB_ADDR(addr & ~mask) |
>>> QI_DEV_EIOTLB_SIZE;
>> desc.q1 |=
> right, thanks
>>> + }
>>> + qi_submit_sync(&desc, iommu);
>>> +}
>>> +
>> /* PASID-cache invalidation */
>>> +void qi_flush_pasid_cache(struct intel_iommu *iommu, u16 did, u64
>>> granu, int pasid) +{
>>> + struct qi_desc desc;
>>> +
>>> + desc.qw0 = QI_PC_TYPE | QI_PC_DID(did) | QI_PC_GRAN(granu)
>>> | QI_PC_PASID(pasid);
>>> + desc.qw1 = 0;
>>> + desc.qw2 = 0;
>>> + desc.qw3 = 0;
>>> + qi_submit_sync(&desc, iommu);
>>> +}
>>> /*
>>> * Disable Queued Invalidation interface.
>>> */
>>> diff --git a/include/linux/intel-iommu.h
>>> b/include/linux/intel-iommu.h index 5d67d0d4..38e5efb 100644
>>> --- a/include/linux/intel-iommu.h
>>> +++ b/include/linux/intel-iommu.h
>>> @@ -339,7 +339,7 @@ enum {
>>> #define QI_IOTLB_GRAN(gran) (((u64)gran) >>
>>> (DMA_TLB_FLUSH_GRANU_OFFSET-4)) #define QI_IOTLB_ADDR(addr)
>>> (((u64)addr) & VTD_PAGE_MASK) #define
>>> QI_IOTLB_IH(ih) (((u64)ih) << 6) -#define
>>> QI_IOTLB_AM(am) (((u8)am)) +#define
>>> QI_IOTLB_AM(am) (((u8)am) & 0x3f)
>>> #define QI_CC_FM(fm) (((u64)fm) << 48)
>>> #define QI_CC_SID(sid) (((u64)sid) << 32)
>>> @@ -357,17 +357,22 @@ enum {
>>> #define QI_PC_DID(did) (((u64)did) << 16)
>>> #define QI_PC_GRAN(gran) (((u64)gran) << 4)
>>>
>>> -#define QI_PC_ALL_PASIDS (QI_PC_TYPE | QI_PC_GRAN(0))
>>> -#define QI_PC_PASID_SEL (QI_PC_TYPE | QI_PC_GRAN(1))
>>> +/* PASID cache invalidation granu */
>>> +#define QI_PC_ALL_PASIDS 0
>>> +#define QI_PC_PASID_SEL 1
>>>
>>> #define QI_EIOTLB_ADDR(addr) ((u64)(addr) & VTD_PAGE_MASK)
>>> #define QI_EIOTLB_GL(gl) (((u64)gl) << 7)
>>> #define QI_EIOTLB_IH(ih) (((u64)ih) << 6)
>>> -#define QI_EIOTLB_AM(am) (((u64)am))
>>> +#define QI_EIOTLB_AM(am) (((u64)am) & 0x3f)
>>> #define QI_EIOTLB_PASID(pasid) (((u64)pasid) << 32)
>>> #define QI_EIOTLB_DID(did) (((u64)did) << 16)
>>> #define QI_EIOTLB_GRAN(gran) (((u64)gran) << 4)
>>>
>>> +/* QI Dev-IOTLB inv granu */
>>> +#define QI_DEV_IOTLB_GRAN_ALL 1
>>> +#define QI_DEV_IOTLB_GRAN_PASID_SEL 0
>>> +
>>> #define QI_DEV_EIOTLB_ADDR(a) ((u64)(a) & VTD_PAGE_MASK)
>>> #define QI_DEV_EIOTLB_SIZE (((u64)1) << 11)
>>> #define QI_DEV_EIOTLB_GLOB(g) ((u64)g)
>>> @@ -658,8 +663,16 @@ extern void qi_flush_context(struct
>>> intel_iommu *iommu, u16 did, u16 sid, u8 fm, u64 type);
>>> extern void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64
>>> addr, unsigned int size_order, u64 type);
>>> +extern void qi_flush_piotlb(struct intel_iommu *iommu, u16 did,
>>> u64 addr,
>>> + u32 pasid, unsigned int size_order, u64
>>> type); extern void qi_flush_dev_iotlb(struct intel_iommu *iommu,
>>> u16 sid, u16 pfsid, u16 qdep, u64 addr, unsigned mask);
>>> +
>>> +extern void qi_flush_dev_piotlb(struct intel_iommu *iommu, u16
>>> sid, u16 pfsid,
>>> + u32 pasid, u16 qdep, u64 addr, unsigned
>>> size, u64 granu); +
>>> +extern void qi_flush_pasid_cache(struct intel_iommu *iommu, u16
>>> did, u64 granu, int pasid); +
>>> extern int qi_submit_sync(struct qi_desc *desc, struct intel_iommu
>>> *iommu);
>>> extern int dmar_ir_support(void);
>>>
>>
>> Thanks
>>
>> Eric
>
> [Jacob Pan]
>