mirror of https://github.com/acidanthera/audk.git
9ed745b967
The "mRecycledMapInfos" list implements an internal pool of unused MAP_INFO structures between the IoMmuUnmap() and IoMmuMap() functions. The original goal was to allow IoMmuUnmap() to tear down CommonBuffer mappings without releasing any memory: IoMmuUnmap() would recycle the MAP_INFO structure to the list, and IoMmuMap() would always check the list first, before allocating a brand new MAP_INFO structure. In one of the following patches, we'll change OvmfPkg/IoMmuDxe so that it unmaps all existent bus master operations (CommonBuffer, Read, Write) at ExitBootServices(), strictly after the individual device drivers abort pending DMA on the devices they manage, in their own ExitBootServices() notification functions. For this, rename and repurpose the list to track all live mappings. This means that IoMmuUnmap() will always release a MAP_INFO structure (even when cleaning up a CommonBuffer operation). That's fine (for now), because device drivers are no longer expected to call Unmap() in their ExitBootServices() notification functions. In theory, we could also move the allocation and freeing of the stash buffer from IoMmuAllocateBuffer() and IoMmuFreeBuffer(), respectively, to IoMmuMap() and IoMmuUnmap(). However, this would require allocating and freeing a stash buffer in *both* IoMmuMap() and IoMmuUnmap(), as IoMmuMap() performs in-place decryption for CommonBuffer operations, and IoMmuUnmap() performs in-place encryption for the same. By keeping the stash buffer allocation as-is, not only do we keep the code almost fully undisturbed, but - we also continue to guarantee that IoMmuUnmap() succeeds: allocating a stash buffer in IoMmuUnmap(), for in-place encryption after a CommonBuffer operation, could fail; - we also keep IoMmuUnmap() largely reusable for ExitBootServices() callback context: allocating a stash buffer in IoMmuUnmap() would simply be forbidden in that context. Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Jiewen Yao <jiewen.yao@intel.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Jiewen Yao <jiewen.yao@intel.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Brijesh Singh <brijesh.singh@amd.com> Tested-by: Brijesh Singh <brijesh.singh@amd.com> |
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|---|---|---|
| AppPkg | ||
| ArmPkg | ||
| ArmPlatformPkg | ||
| ArmVirtPkg | ||
| BaseTools | ||
| BeagleBoardPkg | ||
| Conf | ||
| CorebootModulePkg | ||
| CorebootPayloadPkg | ||
| CryptoPkg | ||
| DuetPkg | ||
| EdkCompatibilityPkg | ||
| EdkShellBinPkg | ||
| EdkShellPkg | ||
| EmbeddedPkg | ||
| EmulatorPkg | ||
| FatBinPkg | ||
| FatPkg | ||
| IntelFrameworkModulePkg | ||
| IntelFrameworkPkg | ||
| IntelFsp2Pkg | ||
| IntelFsp2WrapperPkg | ||
| IntelFspPkg | ||
| IntelFspWrapperPkg | ||
| IntelSiliconPkg | ||
| MdeModulePkg | ||
| MdePkg | ||
| NetworkPkg | ||
| Nt32Pkg | ||
| Omap35xxPkg | ||
| OptionRomPkg | ||
| OvmfPkg | ||
| PcAtChipsetPkg | ||
| PerformancePkg | ||
| QuarkPlatformPkg | ||
| QuarkSocPkg | ||
| SecurityPkg | ||
| ShellBinPkg | ||
| ShellPkg | ||
| SignedCapsulePkg | ||
| SourceLevelDebugPkg | ||
| StdLib | ||
| StdLibPrivateInternalFiles | ||
| UefiCpuPkg | ||
| UnixPkg | ||
| Vlv2DeviceRefCodePkg | ||
| Vlv2TbltDevicePkg | ||
| .gitignore | ||
| BuildNotes2.txt | ||
| Contributions.txt | ||
| Edk2Setup.bat | ||
| License.txt | ||
| Maintainers.txt | ||
| Readme.md | ||
| edksetup.bat | ||
| edksetup.sh | ||
Readme.md
EDK II Project
A modern, feature-rich, cross-platform firmware development environment for the UEFI and PI specifications from www.uefi.org.
Contributions to the EDK II open source project are covered by the TianoCore Contribution Agreement 1.1
The majority of the content in the EDK II open source project uses a BSD 2-Clause License. The EDK II open source project contains the following components that are covered by additional licenses:
- AppPkg/Applications/Python/Python-2.7.2/Tools/pybench
- AppPkg/Applications/Python/Python-2.7.2
- AppPkg/Applications/Python/Python-2.7.10
- BaseTools/Source/C/BrotliCompress
- MdeModulePkg/Library/BrotliCustomDecompressLib
- OvmfPkg
- CryptoPkg/Library/OpensslLib/openssl
The EDK II Project is composed of packages. The maintainers for each package are listed in Maintainers.txt.