The SynchronousRequest(), programs the vring descriptor with the buffers pointed-by virtio-blk requests, status and memory that is referenced inside the request header.
The patch uses VIRTIO_DEVICE_PROTOCOL.MapSharedBuffer() function to map host address to device address and programs the vring descriptor with device addresses. 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/VirtioBlkDxe/VirtioBlk.h | 1 + OvmfPkg/VirtioBlkDxe/VirtioBlk.c | 121 +++++++++++++++++--- 2 files changed, 109 insertions(+), 13 deletions(-) diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.h b/OvmfPkg/VirtioBlkDxe/VirtioBlk.h index 6c402ca88ea4..612994d261bc 100644 --- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.h +++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.h @@ -41,6 +41,7 @@ typedef struct { VRING Ring; // VirtioRingInit 2 EFI_BLOCK_IO_PROTOCOL BlockIo; // VirtioBlkInit 1 EFI_BLOCK_IO_MEDIA BlockIoMedia; // VirtioBlkInit 1 + VOID *RingMapping; // VirtioBlkInit 1 } VBLK_DEV; #define VIRTIO_BLK_FROM_BLOCK_IO(BlockIoPointer) \ diff --git a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c index bff15fe3add1..57baceb20a19 100644 --- a/OvmfPkg/VirtioBlkDxe/VirtioBlk.c +++ b/OvmfPkg/VirtioBlkDxe/VirtioBlk.c @@ -251,6 +251,11 @@ SynchronousRequest ( volatile VIRTIO_BLK_REQ Request; volatile UINT8 HostStatus; DESC_INDICES Indices; + VOID *RequestMapping; + VOID *StatusMapping; + VOID *BufferMapping; + EFI_PHYSICAL_ADDRESS DeviceAddress; + EFI_STATUS Status; BlockSize = Dev->BlockIoMedia.BlockSize; @@ -289,14 +294,30 @@ SynchronousRequest ( ASSERT (Dev->Ring.QueueSize >= 3); // + // Map virtio-blk request header + // + Status = VirtioMapAllBytesInSharedBuffer ( + Dev->VirtIo, + VirtioOperationBusMasterRead, + (VOID *) &Request, + sizeof Request, + &DeviceAddress, + &RequestMapping + ); + if (EFI_ERROR (Status)) { + return Status; + } + + // // virtio-blk header in first desc // - VirtioAppendDesc (&Dev->Ring, (UINTN) &Request, sizeof Request, + VirtioAppendDesc (&Dev->Ring, (UINTN) DeviceAddress, sizeof Request, VRING_DESC_F_NEXT, &Indices); // // data buffer for read/write in second desc // + BufferMapping = NULL; if (BufferSize > 0) { // // From virtio-0.9.5, 2.3.2 Descriptor Table: @@ -309,29 +330,86 @@ SynchronousRequest ( ASSERT (BufferSize <= SIZE_1GB); // + // Map data buffer + // + if (RequestIsWrite) { + Status = VirtioMapAllBytesInSharedBuffer ( + Dev->VirtIo, + VirtioOperationBusMasterRead, + (VOID *) Buffer, + BufferSize, + &DeviceAddress, + &BufferMapping + ); + } else { + Status = VirtioMapAllBytesInSharedBuffer ( + Dev->VirtIo, + VirtioOperationBusMasterWrite, + (VOID *) Buffer, + BufferSize, + &DeviceAddress, + &BufferMapping + ); + } + + if (EFI_ERROR (Status)) { + goto Unmap_Request_Buffer; + } + + // // VRING_DESC_F_WRITE is interpreted from the host's point of view. // - VirtioAppendDesc (&Dev->Ring, (UINTN) Buffer, (UINT32) BufferSize, + VirtioAppendDesc (&Dev->Ring, (UINTN) DeviceAddress, (UINT32) BufferSize, VRING_DESC_F_NEXT | (RequestIsWrite ? 0 : VRING_DESC_F_WRITE), &Indices); } // + // Map virtio-blk status header + // + Status = VirtioMapAllBytesInSharedBuffer ( + Dev->VirtIo, + VirtioOperationBusMasterWrite, + (VOID *) &HostStatus, + sizeof HostStatus, + &DeviceAddress, + &StatusMapping + ); + if (EFI_ERROR (Status)) { + goto Unmap_Data_Buffer; + } + + // // host status in last (second or third) desc // - VirtioAppendDesc (&Dev->Ring, (UINTN) &HostStatus, sizeof HostStatus, + VirtioAppendDesc (&Dev->Ring, (UINTN) DeviceAddress, sizeof HostStatus, VRING_DESC_F_WRITE, &Indices); // // virtio-blk's only virtqueue is #0, called "requestq" (see Appendix D). // - if (VirtioFlush (Dev->VirtIo, 0, &Dev->Ring, &Indices, - NULL) == EFI_SUCCESS && + if (VirtioFlush (Dev->VirtIo, 0, &Dev->Ring, &Indices, NULL) != EFI_SUCCESS) { + Status = EFI_DEVICE_ERROR; + } + + // + // Unmap the HostStatus buffer before accessing it + // + Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, StatusMapping); + + if (Status != EFI_DEVICE_ERROR && HostStatus == VIRTIO_BLK_S_OK) { - return EFI_SUCCESS; + Status = EFI_SUCCESS; + } else { + Status = EFI_DEVICE_ERROR; } - return EFI_DEVICE_ERROR; +Unmap_Data_Buffer: + Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, BufferMapping); +Unmap_Request_Buffer: + Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, RequestMapping); + + return Status; } @@ -601,6 +679,7 @@ VirtioBlkInit ( UINT8 AlignmentOffset; UINT32 OptIoSize; UINT16 QueueSize; + UINT64 RingBaseShift; PhysicalBlockExp = 0; AlignmentOffset = 0; @@ -728,26 +807,33 @@ VirtioBlkInit ( goto Failed; } + Status = VirtioRingMap (Dev->VirtIo, &Dev->Ring, &RingBaseShift, + &Dev->RingMapping); + if (EFI_ERROR (Status)) { + goto ReleaseQueue; + } + // // Additional steps for MMIO: align the queue appropriately, and set the // size. If anything fails from here on, we must release the ring resources. // Status = Dev->VirtIo->SetQueueNum (Dev->VirtIo, QueueSize); if (EFI_ERROR (Status)) { - goto ReleaseQueue; + goto UnmapQueue; } Status = Dev->VirtIo->SetQueueAlign (Dev->VirtIo, EFI_PAGE_SIZE); if (EFI_ERROR (Status)) { - goto ReleaseQueue; + goto UnmapQueue; } // // step 4c -- Report GPFN (guest-physical frame number) of queue. // - Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo, &Dev->Ring, 0); + Status = Dev->VirtIo->SetQueueAddress (Dev->VirtIo, &Dev->Ring, + RingBaseShift); if (EFI_ERROR (Status)) { - goto ReleaseQueue; + goto UnmapQueue; } @@ -758,7 +844,7 @@ VirtioBlkInit ( Features &= ~(UINT64)VIRTIO_F_VERSION_1; Status = Dev->VirtIo->SetGuestFeatures (Dev->VirtIo, Features); if (EFI_ERROR (Status)) { - goto ReleaseQueue; + goto UnmapQueue; } } @@ -768,7 +854,7 @@ VirtioBlkInit ( NextDevStat |= VSTAT_DRIVER_OK; Status = Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, NextDevStat); if (EFI_ERROR (Status)) { - goto ReleaseQueue; + goto UnmapQueue; } // @@ -811,7 +897,10 @@ VirtioBlkInit ( } return EFI_SUCCESS; +UnmapQueue: + Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, Dev->RingMapping); ReleaseQueue: + VirtioRingUninit (Dev->VirtIo, &Dev->Ring); Failed: @@ -885,6 +974,12 @@ VirtioBlkExitBoot ( // Dev = Context; Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, 0); + + // + // Unmap the ring buffer so that hypervisor can not get a readable data + // after device is reset. + // + Dev->VirtIo->UnmapSharedBuffer (Dev->VirtIo, Dev->RingMapping); } /** -- 2.7.4 _______________________________________________ edk2-devel mailing list [email protected] https://lists.01.org/mailman/listinfo/edk2-devel
