写东西之前都不看官方例子的么？
d27K9s2c8@1M7s2y4Q4x3@1q4Q4x3V1k6Q4x3V1k6Y4K9i4c8Z5N6h3u0Q4x3X3g2U0L8$3#2Q4x3V1k6E0K9h3y4J5L8%4y4G2k6Y4c8Q4x3V1k6i4K9h3&6V1L8%4N6K6i4K6u0V1k6s2u0A6N6X3g2J5i4K6u0V1M7$3q4E0M7r3I4W2M7#2)9J5c8Y4c8J5k6h3g2Q4x3V1k6E0j5i4y4@1k6i4u0Q4x3V1k6Y4k6h3&6W2M7X3q4D9i4K6u0r3K9h3!0U0N6r3I4Q4x3V1k6%4k6r3@1`.

            irp->MdlAddress = IoAllocateMdl( Buffer,
                                             Length,
                                             FALSE,
                                             FALSE,
                                             NULL );

            if (irp->MdlAddress == NULL) {
                IoFreeIrp( irp );
                return (PIRP) NULL;
            }

            try {
                MmProbeAndLockPages( irp->MdlAddress,
                                     KernelMode,
                                     (LOCK_OPERATION) (MajorFunction == IRP_MJ_READ ? IoWriteAccess : IoReadAccess) );
            } except(EXCEPTION_EXECUTE_HANDLER) {
                  if (irp->MdlAddress != NULL) {
                      IoFreeMdl( irp->MdlAddress );
                  }
                  IoFreeIrp( irp );
                  return (PIRP) NULL;
            }

谢谢大佬们的回答