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

[Laszlo Ersek <lersek@redhat.com>]

On 09/08/17 17:50, Brijesh Singh wrote:
> Patch 4 - 10
> 
> Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
> Tested-by: Brijesh Singh <brijesh.singh@amd.com>
> 
> Thank you Laszlo! I will work to finish virtio-net next week.

Awesome!

Thanks!
Laszlo

> On 09/07/2017 05:41 PM, Laszlo Ersek wrote:
>> 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(-)
>>