search for: iotlb_upd

...that is responsible for > > the HVA translations is better than two. > > > > So the difference whether or not use memory table information: > > Current: > > 1) SET_MEM_TABLE: GPA->HVA > > 2) Qemu GIOVA->GPA > > 3) Qemu GPA->HVA > > 4) IOTLB_UPDATE: GIOVA->HVA > > If I understand correctly you want to drop step 3 consider it might be buggy > which is just 19 lines of code in qemu (vhost_memory_region_lookup()). This > will ends up: > > 1) Do GPA->HVA translation in IOTLB_UPDATE path (I believe we won't want to...

...that is responsible for > > the HVA translations is better than two. > > > > So the difference whether or not use memory table information: > > Current: > > 1) SET_MEM_TABLE: GPA->HVA > > 2) Qemu GIOVA->GPA > > 3) Qemu GPA->HVA > > 4) IOTLB_UPDATE: GIOVA->HVA > > If I understand correctly you want to drop step 3 consider it might be buggy > which is just 19 lines of code in qemu (vhost_memory_region_lookup()). This > will ends up: > > 1) Do GPA->HVA translation in IOTLB_UPDATE path (I believe we won't want to...

On Mon, Dec 24, 2018 at 11:43:31AM +0800, Jason Wang wrote: > > On 2018/12/14 ??9:20, Michael S. Tsirkin wrote: > > On Fri, Dec 14, 2018 at 10:43:03AM +0800, Jason Wang wrote: > > > On 2018/12/13 ??10:31, Michael S. Tsirkin wrote: > > > > > Just to make sure I understand this. It looks to me we should: > > > > > > > > > > - allow

On Mon, Dec 24, 2018 at 11:43:31AM +0800, Jason Wang wrote: > > On 2018/12/14 ??9:20, Michael S. Tsirkin wrote: > > On Fri, Dec 14, 2018 at 10:43:03AM +0800, Jason Wang wrote: > > > On 2018/12/13 ??10:31, Michael S. Tsirkin wrote: > > > > > Just to make sure I understand this. It looks to me we should: > > > > > > > > > > - allow

...the difference whether or not use memory table information: > > > > > > Current: > > > > > > 1) SET_MEM_TABLE: GPA->HVA > > > > > > 2) Qemu GIOVA->GPA > > > > > > 3) Qemu GPA->HVA > > > > > > 4) IOTLB_UPDATE: GIOVA->HVA > > > > > > If I understand correctly you want to drop step 3 consider it might be buggy > > > which is just 19 lines of code in qemu (vhost_memory_region_lookup()). This > > > will ends up: > > > > > > 1) Do GPA->HVA tran...

...efence in depth approach. > > My point is that a single code path that is responsible for > the HVA translations is better than two. > So the difference whether or not use memory table information: Current: 1) SET_MEM_TABLE: GPA->HVA 2) Qemu GIOVA->GPA 3) Qemu GPA->HVA 4) IOTLB_UPDATE: GIOVA->HVA If I understand correctly you want to drop step 3 consider it might be buggy which is just 19 lines of code in qemu (vhost_memory_region_lookup()). This will ends up: 1) Do GPA->HVA translation in IOTLB_UPDATE path (I believe we won't want to do it during device IOTLB...

...the HVA translations is better than two. >>> >> So the difference whether or not use memory table information: >> >> Current: >> >> 1) SET_MEM_TABLE: GPA->HVA >> >> 2) Qemu GIOVA->GPA >> >> 3) Qemu GPA->HVA >> >> 4) IOTLB_UPDATE: GIOVA->HVA >> >> If I understand correctly you want to drop step 3 consider it might be buggy >> which is just 19 lines of code in qemu (vhost_memory_region_lookup()). This >> will ends up: >> >> 1) Do GPA->HVA translation in IOTLB_UPDATE path (I believ...

...fs of memory table and using IOMMU API to setup the dma >>>>>>>> mapping in this method >>>>>>> Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? >>>>>>> >>>>>> Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? >>>>> Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE >>>>> to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, >>>>> userspace will set msg->iova to GPA, otherwise userspace will se...

...fs of memory table and using IOMMU API to setup the dma >>>>>>>> mapping in this method >>>>>>> Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? >>>>>>> >>>>>> Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? >>>>> Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE >>>>> to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, >>>>> userspace will set msg->iova to GPA, otherwise userspace will se...

...MU API to setup the dma >>>>>>>>>> mapping in this method >>>>>>>>> Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? >>>>>>>>> >>>>>>>> Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? >>>>>>> Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE >>>>>>> to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, >>>>>>> userspace will set msg->iova to GPA, oth...

...up the dma > > > > > > > > > mapping in this method > > > > > > > > Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? > > > > > > > > > > > > > > > Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? > > > > > > Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE > > > > > > to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, > > > > > > userspace will set msg->iova to GPA,...

...>>>> 5) generate diffs of memory table and using IOMMU API to setup the dma >>>>>> mapping in this method >>>>> Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? >>>>> >>>> Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? >>> Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE >>> to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, >>> userspace will set msg->iova to GPA, otherwise userspace will set >>> msg->i...

...>>>> 5) generate diffs of memory table and using IOMMU API to setup the dma >>>>>> mapping in this method >>>>> Frankly I think that's a bunch of work. Why not a MAP/UNMAP interface? >>>>> >>>> Sure, so that basically VHOST_IOTLB_UPDATE/INVALIDATE I think? >>> Do you mean we let userspace to only use VHOST_IOTLB_UPDATE/INVALIDATE >>> to do the DMA mapping in vhost-vdpa case? When vIOMMU isn't available, >>> userspace will set msg->iova to GPA, otherwise userspace will set >>> msg->i...