Re: [PATCH 00/10] MdeModulePkg, OvmfPkg: unmap DMA buffers at ExitBootServices

["Yao, Jiewen" <jiewen.yao@intel.com>]

Patch 1~3 reviewed-by: Jiewen.yao@intel.com


> -----Original Message-----
> From: Laszlo Ersek [mailto:lersek@redhat.com]
> Sent: Friday, September 8, 2017 6:41 AM
> To: edk2-devel-01 <edk2-devel@lists.01.org>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>; Brijesh Singh
> <brijesh.singh@amd.com>; Dong, Eric <eric.dong@intel.com>; Yao, Jiewen
> <jiewen.yao@intel.com>; Justen, Jordan L <jordan.l.justen@intel.com>; Zeng,
> Star <star.zeng@intel.com>
> Subject: [PATCH 00/10] MdeModulePkg, OvmfPkg: unmap DMA buffers at
> ExitBootServices
> 
> Repo:   https://github.com/lersek/edk2.git
> Branch: iommu_exit_boot
> 
> This series is the result of the discussion under
> 
>   [edk2] [PATCH 0/4] MdeModulePkg: some PCI HC drivers: unmap common
>                      buffers at ExitBootServices()
>   https://lists.01.org/pipermail/edk2-devel/2017-September/014099.html
> 
> At ExitBootServices(), PCI and VirtIo drivers should only care about
> aborting pending DMA on the devices. Cleaning up PciIo mappings (which
> ultimately boil down to IOMMU mappings) for those aborted DMA operations
> should be the job of the IOMMU driver.
> 
> Patches 01 through 03 clean up the AtaAtapiPassThru driver in
> MdeModulePkg a little bit, because at present, (a) it unmaps the buffers
> and disables BMDMA in the wrong order in its DriverBindingStop()
> function, (b) it doesn't abort pending DMA at ExitBootServices().
> 
> This subset can be treated separately from the rest of the series, but I
> thought they belonged loosely together (given that AtaAtapiPassThru is
> used on QEMU's Q35 machine type).
> 
> Patches 04 through 07 remove
> VIRTIO_DEVICE_PROTOCOL.UnmapSharedBuffer()
> calls from the VirtIo drivers' ExitBootServices() handlers.
> 
> (The conversion of VirtioNetDxe to device addresses is still in progress
> -- Brijesh, when you submit v2 of that, under this approach, there is no
> need to change VirtioNetExitBoot() relative to current upstream, and you
> can use VirtioOperationBusMasterRead to map outgoing packets.)
> 
> Patches 08 through 10 make OvmfPkg/IoMmuDxe track all mappings, and
> unmap all mappings (Read, Write, CommonBuffer) that are in effect when
> ExitBootServices() is called. It is ensured that PCI and VirtIo drivers
> abort pending DMA first, and IoMmuDxe clean up the mappings last.
> 
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Cc: Brijesh Singh <brijesh.singh@amd.com>
> Cc: Eric Dong <eric.dong@intel.com>
> Cc: Jiewen Yao <jiewen.yao@intel.com>
> Cc: Jordan Justen <jordan.l.justen@intel.com>
> Cc: Star Zeng <star.zeng@intel.com>
> 
> Thanks
> Laszlo
> 
> Laszlo Ersek (10):
>   MdeModulePkg/AtaAtapiPassThru: cache EnabledPciAttributes
>   MdeModulePkg/AtaAtapiPassThru: unmap DMA buffers after disabling BM
>     DMA
>   MdeModulePkg/AtaAtapiPassThru: disable the device at
>     ExitBootServices()
>   OvmfPkg/VirtioBlkDxe: don't unmap VRING at ExitBootServices()
>   OvmfPkg/VirtioGpuDxe: don't unmap VRING & BackingStore at
>     ExitBootServices
>   OvmfPkg/VirtioRngDxe: don't unmap VRING at ExitBootServices()
>   OvmfPkg/VirtioScsiDxe: don't unmap VRING at ExitBootServices()
>   OvmfPkg/IoMmuDxe: track all mappings
>   OvmfPkg/IoMmuDxe: generalize IoMmuUnmap() to IoMmuUnmapWorker()
>   OvmfPkg/IoMmuDxe: unmap all IOMMU mappings at ExitBootServices()
> 
>  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.c | 103 +++++---
>  MdeModulePkg/Bus/Ata/AtaAtapiPassThru/AtaAtapiPassThru.h |   7 +
>  OvmfPkg/IoMmuDxe/AmdSevIoMmu.c                           | 246
> +++++++++++++++++---
>  OvmfPkg/VirtioBlkDxe/VirtioBlk.c                         |   7 +-
>  OvmfPkg/VirtioGpuDxe/Commands.c                          |  23 +-
>  OvmfPkg/VirtioRngDxe/VirtioRng.c                         |   7 +-
>  OvmfPkg/VirtioScsiDxe/VirtioScsi.c                       |   7 +-
>  7 files changed, 299 insertions(+), 101 deletions(-)
> 
> --
> 2.14.1.3.gb7cf6e02401b