Hi Yi, On 11/6/19 2:31 AM, Liu, Yi L wrote: >> From: Alex Williamson [mailto:alex.williamson@xxxxxxxxxx] >> Sent: Wednesday, November 6, 2019 6:42 AM >> To: Liu, Yi L <yi.l.liu@xxxxxxxxx> >> Subject: Re: [RFC v2 1/3] vfio: VFIO_IOMMU_CACHE_INVALIDATE >> >> On Fri, 25 Oct 2019 11:20:40 +0000 >> "Liu, Yi L" <yi.l.liu@xxxxxxxxx> wrote: >> >>> Hi Kevin, >>> >>>> From: Tian, Kevin >>>> Sent: Friday, October 25, 2019 5:14 PM >>>> To: Liu, Yi L <yi.l.liu@xxxxxxxxx>; alex.williamson@xxxxxxxxxx; >>>> Subject: RE: [RFC v2 1/3] vfio: VFIO_IOMMU_CACHE_INVALIDATE >>>> >>>>> From: Liu, Yi L >>>>> Sent: Thursday, October 24, 2019 8:26 PM >>>>> >>>>> From: Liu Yi L <yi.l.liu@xxxxxxxxxxxxxxx> >>>>> >>>>> When the guest "owns" the stage 1 translation structures, the >>>>> host IOMMU driver has no knowledge of caching structure updates >>>>> unless the guest invalidation requests are trapped and passed down to the host. >>>>> >>>>> This patch adds the VFIO_IOMMU_CACHE_INVALIDATE ioctl with aims at >>>>> propagating guest stage1 IOMMU cache invalidations to the host. >>>>> >>>>> Cc: Kevin Tian <kevin.tian@xxxxxxxxx> >>>>> Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxxxxxxxx> >>>>> Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> >>>>> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx> >>>>> --- >>>>> drivers/vfio/vfio_iommu_type1.c | 55 >>>>> +++++++++++++++++++++++++++++++++++++++++ >>>>> include/uapi/linux/vfio.h | 13 ++++++++++ >>>>> 2 files changed, 68 insertions(+) >>>>> >>>>> diff --git a/drivers/vfio/vfio_iommu_type1.c >>>>> b/drivers/vfio/vfio_iommu_type1.c index 96fddc1d..cd8d3a5 100644 >>>>> --- a/drivers/vfio/vfio_iommu_type1.c >>>>> +++ b/drivers/vfio/vfio_iommu_type1.c >>>>> @@ -124,6 +124,34 @@ struct vfio_regions { >>>>> #define IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu) \ >>>>> (!list_empty(&iommu->domain_list)) >>>>> >>>>> +struct domain_capsule { >>>>> + struct iommu_domain *domain; >>>>> + void *data; >>>>> +}; >>>>> + >>>>> +/* iommu->lock must be held */ >>>>> +static int >>>>> +vfio_iommu_lookup_dev(struct vfio_iommu *iommu, >>>>> + int (*fn)(struct device *dev, void *data), >>>>> + void *data) >>>> >>>> 'lookup' usually means find a device and then return. But the real >>>> purpose here is to loop all the devices within this container and >>>> then do something. Does it make more sense to be vfio_iommu_for_each_dev? >> >> +1 >> >>> yep, I can replace it. >>> >>>> >>>>> +{ >>>>> + struct domain_capsule dc = {.data = data}; >>>>> + struct vfio_domain *d; >>> [...] >>>> 2315,6 +2352,24 @@ >>>>> static long vfio_iommu_type1_ioctl(void *iommu_data, >>>>> >>>>> return copy_to_user((void __user *)arg, &unmap, minsz) ? >>>>> -EFAULT : 0; >>>>> + } else if (cmd == VFIO_IOMMU_CACHE_INVALIDATE) { >>>>> + struct vfio_iommu_type1_cache_invalidate ustruct; >>>> >>>> it's weird to call a variable as struct. >>> >>> Will fix it. >>> >>>>> + int ret; >>>>> + >>>>> + minsz = offsetofend(struct >>>>> vfio_iommu_type1_cache_invalidate, >>>>> + info); >>>>> + >>>>> + if (copy_from_user(&ustruct, (void __user *)arg, minsz)) >>>>> + return -EFAULT; >>>>> + >>>>> + if (ustruct.argsz < minsz || ustruct.flags) >>>>> + return -EINVAL; >>>>> + >>>>> + mutex_lock(&iommu->lock); >>>>> + ret = vfio_iommu_lookup_dev(iommu, vfio_cache_inv_fn, >>>>> + &ustruct); >>>>> + mutex_unlock(&iommu->lock); >>>>> + return ret; >>>>> } >>>>> >>>>> return -ENOTTY; >>>>> diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h >>>>> index 9e843a1..ccf60a2 100644 >>>>> --- a/include/uapi/linux/vfio.h >>>>> +++ b/include/uapi/linux/vfio.h >>>>> @@ -794,6 +794,19 @@ struct vfio_iommu_type1_dma_unmap { >>>>> #define VFIO_IOMMU_ENABLE _IO(VFIO_TYPE, VFIO_BASE + 15) >>>>> #define VFIO_IOMMU_DISABLE _IO(VFIO_TYPE, VFIO_BASE + 16) >>>>> >>>>> +/** >>>>> + * VFIO_IOMMU_CACHE_INVALIDATE - _IOWR(VFIO_TYPE, VFIO_BASE + >>>>> 24, >> >> What's going on with these ioctl numbers? AFAICT[1] we've used up through >> VFIO_BASE + 21, this jumps to 24, the next patch skips to 27, then the last patch fills >> in 28 & 29. Thanks, > > Hi Alex, > > I rebase my patch to Eric's nested stage translation patches. His base also introduced > IOCTLs. I should have made it better. I'll try to sync with Eric to serialize the IOCTLs. > > [PATCH v6 00/22] SMMUv3 Nested Stage Setup by Eric Auger > https://lkml.org/lkml/2019/3/17/124 Feel free to choose your IOCTL numbers without taking care of my series. I will adapt to yours if my work gets unblocked at some point. Thanks Eric > > Thanks, > Yi Liu > >> Alex >> >> [1] git grep -h VFIO_BASE | grep "VFIO_BASE +" | grep -e ^#define | \ >> awk '{print $NF}' | tr -d ')' | sort -u -n >
