diff options
Diffstat (limited to 'general/PLX9x5x/sys/Write.c')
| -rw-r--r-- | general/PLX9x5x/sys/Write.c | 35 |
1 files changed, 33 insertions, 2 deletions
diff --git a/general/PLX9x5x/sys/Write.c b/general/PLX9x5x/sys/Write.c index 3e4d8b53..cef1d71d 100644 --- a/general/PLX9x5x/sys/Write.c +++ b/general/PLX9x5x/sys/Write.c @@ -79,6 +79,15 @@ Return Value: } // + // Set the transaction's Single Transfer Requirement if + // the user application asked for it. This needs to be + // set before initializing the transaction. + // + WdfDmaTransactionSetSingleTransferRequirement( + devExt->WriteDmaTransaction, + devExt->RequireSingleTransfer); + + // // Following code illustrates two different ways of initializing a DMA // transaction object. If ASSOC_WRITE_REQUEST_WITH_DMA_TRANSACTION is // defined in the sources file, the first section will be used. @@ -124,8 +133,9 @@ Return Value: PTRANSACTION_CONTEXT transContext; PMDL mdl; PVOID virtualAddress; - ULONG length; + size_t length; +#ifndef SIMULATE_MEMORY_FRAGMENTATION // // Initialize this new DmaTransaction with direct parameters. // @@ -138,6 +148,27 @@ Return Value: virtualAddress = MmGetMdlVirtualAddress(mdl); length = MmGetMdlByteCount(mdl); +#else + PVOID buffer; + + // + // For illustrative purposes, copy the Request's memory to a + // heavily fragmented MDL chain. If RequireSingleTransfer was set, + // then KMDF will attempt to fulfill the DMA transaction in a single + // transfer. Otherwise, the transaction may require several operations + // in which case PLxEvtProgramWriteDma will be invoked multiple times. + // + status = WdfRequestRetrieveInputBuffer(Request, 0, &buffer, &length); + if (!NT_SUCCESS(status)) { + TraceEvents(TRACE_LEVEL_ERROR, DBG_WRITE, + "WdfRequestRetrieveInputBuffer failed: %!STATUS!", status); + goto CleanUp; + } + + mdl = devExt->WriteMdlChain; + virtualAddress = MmGetMdlVirtualAddress(mdl); + CopyBufferToMdlChain(buffer, length, mdl); +#endif // SIMULATE_MEMORY_FRAGMENTATION _Analysis_assume_(length > 0); status = WdfDmaTransactionInitialize( devExt->WriteDmaTransaction, @@ -160,7 +191,7 @@ Return Value: transContext = PLxGetTransactionContext( devExt->WriteDmaTransaction ); transContext->Request = Request; } -#endif +#endif // ASSOC_WRITE_REQUEST_WITH_DMA_TRANSACTION #if 0 //FYI // |