内存问题

  MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority);
这个函数的功能我知道，第一个参数的意义我也知道，请问一下第二个参数是什么意思，小弟由于实际需要才看驱动开发，以前没搞过这方面的工作，希望各位不吝赐教，还有不知哪位大虾能推荐下关于这些函数的详细介绍文档，我在DDK里没找到，谢谢

DDK 的帮助文档里面都有的：

Specifies an MM_PAGE_PRIORITY value that indicates the importance of success under low available PTE conditions. Possible values include LowPagePriority, NormalPagePriority, and HighPagePriority.

LowPagePriority indicates that the mapping request can fail if the system is fairly low on resources. An example of this situation is a noncritical network connection where the driver can handle the mapping failure.

NormalPagePriority indicates that the mapping request can fail if the system is very low on resources. An example of this situation is a noncritical local file system request.

HighPagePriority indicates that the mapping request must not fail unless the system is completely out of resources. An example of this situation is the paging file path in a driver.

明白了，谢谢您

请教下，我想在passthru里获得发送的数据包内容把它传给用户程序，应该把IRP_MJ_READ的实现部分写在哪里呢？是写在miniport.c里吗还是写在passthru.c里