The patch extends VIRTIO_DEVICE_PROTOCOL to provide the following new member functions:
- AllocateSharedPages : allocate a memory region suitable for sharing between guest and hypervisor (e.g ring buffer). - FreeSharedPages: free the memory allocated using AllocateSharedPages (). - MapSharedBuffer: map a host address to device address suitable to share with device for bus master operations. - UnmapSharedBuffer: unmap the device address obtained through the MapSharedBuffer(). Suggested-by: Laszlo Ersek <[email protected]> Cc: Ard Biesheuvel <[email protected]> Cc: Jordan Justen <[email protected]> Cc: Tom Lendacky <[email protected]> Cc: Laszlo Ersek <[email protected]> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Brijesh Singh <[email protected]> --- OvmfPkg/Include/Protocol/VirtioDevice.h | 143 ++++++++++++++++++++ 1 file changed, 143 insertions(+) diff --git a/OvmfPkg/Include/Protocol/VirtioDevice.h b/OvmfPkg/Include/Protocol/VirtioDevice.h index edb20c18822c..14f980d7bf0a 100644 --- a/OvmfPkg/Include/Protocol/VirtioDevice.h +++ b/OvmfPkg/Include/Protocol/VirtioDevice.h @@ -5,6 +5,7 @@ and should not be used outside of the EDK II tree. Copyright (c) 2013, ARM Ltd. All rights reserved.<BR> + Copyright (c) 2017, AMD Inc, All rights reserved.<BR> This program and the accompanying materials are licensed and made available under the terms and conditions of the BSD License which accompanies this @@ -31,6 +32,25 @@ typedef struct _VIRTIO_DEVICE_PROTOCOL VIRTIO_DEVICE_PROTOCOL; +// +// VIRTIO Operation for VIRTIO_MAP_SHARED +// +typedef enum { + // + // A read operation from system memory by a bus master + // + VirtioOperationBusMasterRead, + // + // A write operation to system memory by a bus master + // + VirtioOperationBusMasterWrite, + // + // Provides both read and write access to system memory by both the + // processor and a bus master + // + VirtioOperationBusMasterCommonBuffer, +} VIRTIO_MAP_OPERATION; + /** Read a word from the device-specific I/O region of the Virtio Header. @@ -319,6 +339,121 @@ EFI_STATUS IN UINT8 DeviceStatus ); +/** + + Allocates pages that are suitable for an VirtioOperationBusMasterCommonBuffer + mapping. This means that the buffer allocated by this function supports + simultaneous access by both the processor and the bus master. The device + address that the bus master uses to access the buffer must be retrieved with + a call to VIRTIO_MAP_SHARED. + + @param[in] This The protocol instance pointer. + + @param[in] Pages The number of pages to allocate. + + @param[in,out] HostAddress A pointer to store the system memory base + address of the allocated range. + + @retval EFI_SUCCESS The requested memory pages were allocated. + @retval EFI_OUT_OF_RESOURCES The memory pages could not be allocated. + +**/ +typedef +EFI_STATUS +(EFIAPI *VIRTIO_ALLOCATE_SHARED)( + IN VIRTIO_DEVICE_PROTOCOL *This, + IN UINTN Pages, + IN OUT VOID **HostAddress + ); + +/** + Frees memory that was allocated with VIRTIO_ALLOCATE_SHARED. + + @param[in] This The protocol instance pointer. + + @param[in] Pages The number of pages to free. + + @param[in] HostAddress The system memory base address of the allocated + range. + +**/ +typedef +VOID +(EFIAPI *VIRTIO_FREE_SHARED)( + IN VIRTIO_DEVICE_PROTOCOL *This, + IN UINTN Pages, + IN VOID *HostAddress + ); + +/** + Provides the virtio device address required to access system memory from a + DMA bus master. + + The interface follows the same usage pattern as defined in UEFI spec 2.6 + (Section 13.2 PCI Root Bridge I/O Protocol) + + @param[in] This The protocol instance pointer. + + @param[in] Operation Indicates if the bus master is going to + read or write to system memory. + + @param[in] HostAddress The system memory address to map to shared + buffer address. + + @param[in,out] NumberOfBytes On input the number of bytes to map. + On output the number of bytes that were + mapped. + + @param[out] DeviceAddress The resulting shared map address for the + bus master to access the hosts HostAddress. + + @param[out] Mapping A resulting taken to pass to + VIRTIO_UNMAP_SHARED. + + @retval EFI_SUCCESS The range was mapped for the returned + NumberOfBytes. + @retval EFI_UNSUPPORTED The HostAddress cannot be mapped as a + common buffer. + @retval EFI_INVALID_PARAMETER One or more parameters are invalid. + @retval EFI_OUT_OF_RESOURCES The request could not be completed due to + a lack of resources. + @retval EFI_DEVICE_ERROR The system hardware could not map the + requested address. +**/ + +typedef +EFI_STATUS +(EFIAPI *VIRTIO_MAP_SHARED) ( + IN VIRTIO_DEVICE_PROTOCOL *This, + IN VIRTIO_MAP_OPERATION Operation, + IN VOID *HostAddress, + IN OUT UINTN *NumberOfBytes, + OUT EFI_PHYSICAL_ADDRESS *DeviceAddress, + OUT VOID **Mapping + ); + +/** + Completes the VIRTIO_MAP_SHARED operation and releases any corresponding + resources. + + @param[in] This The protocol instance pointer. + + @param[in] Mapping The mapping token returned from + VIRTIO_MAP_SHARED. + + @retval EFI_SUCCESS The range was unmapped. + @retval EFI_INVALID_PARAMETER Mapping is not a value that was returned by + VIRTIO_MAP_SHARED. Passing an invalid Mapping + token can cause undefined behavior. + @retval EFI_DEVICE_ERROR The data was not committed to the target + system memory. +**/ +typedef +EFI_STATUS +(EFIAPI *VIRTIO_UNMAP_SHARED)( + IN VIRTIO_DEVICE_PROTOCOL *This, + IN VOID *Mapping + ); /** @@ -359,6 +494,14 @@ struct _VIRTIO_DEVICE_PROTOCOL { // Functions to read/write Device Specific headers VIRTIO_DEVICE_WRITE WriteDevice; VIRTIO_DEVICE_READ ReadDevice; + + // + // Functions to allocate, free, map and unmap shared buffer + // + VIRTIO_ALLOCATE_SHARED AllocateSharedPages; + VIRTIO_FREE_SHARED FreeSharedPages; + VIRTIO_MAP_SHARED MapSharedBuffer; + VIRTIO_UNMAP_SHARED UnmapSharedBuffer; }; extern EFI_GUID gVirtioDeviceProtocolGuid; -- 2.7.4 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
